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what rights do people have , and where do they come from ? who gets to make decisions for others and on what authority ? and how can we organize society to meet people 's needs ? these questions challenged an entire nation during the upheaval of the french revolution . by the end of the 18th century , europe had undergone a profound intellectual and cultural shift known as the enlightenment . philosophers and artists promoted reason and human freedom over tradition and religion . the rise of a middle class and printed materials encouraged political awareness , and the american revolution had turned a former english colony into an independent republic . yet france , one of the largest and richest countries in europe was still governed by an ancient regime of three rigid social classes called estates . the monarch king louis xvi based his authority on divine right and granted special privileges to the first and second estates , the catholic clergy , and the nobles . the third estate , middle class merchants and craftsmen , as well as over 20 million peasants , had far less power and they were the only ones who paid taxes , not just to the king , but to the other estates as well . in bad harvest years , taxation could leave peasants with almost nothing while the king and nobles lived lavishly on their extracted wealth . but as france sank into debt due to its support of the american revolution and its long-running war with england , change was needed . king louis appointed finance minister jacques necker , who pushed for tax reforms and won public support by openly publishing the government 's finances . but the king 's advisors strongly opposed these initiatives . desperate for a solution , the king called a meeting of the estates-general , an assembly of representatives from the three estates , for the first time in 175 years . although the third estate represented 98 % of the french population , its vote was equal to each of the other estates . and unsurprisingly , both of the upper classes favored keeping their privileges . realizing they could n't get fair representation , the third estate broke off , declared themselves the national assembly , and pledged to draft a new constitution with or without the other estates . king louis ordered the first and second estates to meet with the national assembly , but he also dismissed necker , his popular finance minister . in response , thousands of outraged parisians joined with sympathetic soldiers to storm the bastille prison , a symbol of royal power and a large storehouse of weapons . the revolution had begun . as rebellion spread throughout the country , the feudal system was abolished . the assembly 's declaration of the rights of man and citizen proclaimed a radical idea for the time -- that individual rights and freedoms were fundamental to human nature and government existed only to protect them . their privileges gone , many nobles fled abroad , begging foreign rulers to invade france and restore order . and while louis remained as the figurehead of the constitutional monarchy , he feared for his future . in 1791 , he tried to flee the country but was caught . the attempted escape shattered people 's faith in the king . the royal family was arrested and the king charged with treason . after a trial , the once-revered king was publicly beheaded , signaling the end of one thousand years of monarchy and finalizing the september 21st declaration of the first french republic , governed by the motto `` liberté , égalité , fraternité . '' nine months later , queen marie antoinette , a foreigner long-mocked as `` madame déficit '' for her extravagant reputation , was executed as well . but the revolution would not end there . some leaders , not content with just changing the government , sought to completely transform french society -- its religion , its street names , even its calendar . as multiple factions formed , the extremist jacobins lead by maximilien robespierre launched a reign of terror to suppress the slightest dissent , executing over 20,000 people before the jacobin 's own downfall . meanwhile , france found itself at war with neighboring monarchs seeking to strangle the revolution before it spread . amidst the chaos , a general named napoleon bonaparte took charge , becoming emperor as he claimed to defend the revolution 's democratic values . all in all , the revolution saw three constitutions and five governments within ten years , followed by decades alternating between monarchy and revolt before the next republic formed in 1871 . and while we celebrate the french revolution 's ideals , we still struggle with many of the same basic questions raised over two centuries ago .
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the monarch king louis xvi based his authority on divine right and granted special privileges to the first and second estates , the catholic clergy , and the nobles . the third estate , middle class merchants and craftsmen , as well as over 20 million peasants , had far less power and they were the only ones who paid taxes , not just to the king , but to the other estates as well . in bad harvest years , taxation could leave peasants with almost nothing while the king and nobles lived lavishly on their extracted wealth .
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which estate paid taxes to the king ?
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this image of the vitruvian man , taken from leonardo 's sketches , has become one of the most recognizable symbols of the renaissance . but why ? it 's a simple pen and ink drawing , right ? wrong ! let 's start to answer this question with a math problem . i know how to calculate the area of a circle . i take the value for pi and multiply it by the radius squared . i also know how to take the area of a square . i multiply the base by itself . but how can i take the area of a circle and create a square with an equal area ? this is a problem often called `` squaring a circle '' that was first proposed in the ancient world . and like many ideas of the ancient world , it was given new life during the renaissance . as it turns out , this problem is impossible to solve because of the nature of pi , but that 's another story . leonardo 's sketch , which is influenced by the writings of the roman architect , vitruvius , places a man firmly at the center of a circle and a square . vitruvius claimed the navel is the center of the human body and that if one takes a compass and places the fixed point on the navel , a circle can be drawn perfectly around the body . additionally , vitruvius recognized that arm span and height have a nearly perfect correspondence in the human body , thus placing the body perfectly inside a square as well . leonardo used the ideas of vitruvius to solve the problem of squaring a circle metaphorically using mankind as the area for both shapes . leonardo was n't just thinking about vitruvius , though . there was an intellectual movement in italy at the time called neoplatonism . this movement took an old concept from the 4th century developed by plato and aristotle , called `` the great chain of being . '' this belief holds that the universe has a hierarchy resembling a chain , and that chain starts at the top with god , then travels down through the angels , planets , stars , and all lifeforms before ending with demons and devils . early in this philosophic movement , it was thought that mankind 's place in this chain was exactly in the center . because humans have a mortal body accompanied by an immortal soul , we divide the universe nicely in half . around the time leonardo sketched the vitruvian man , however , a neoplatonist named pico della mirandola had a different idea . he pried mankind off the chain and claimed that humans have a unique ability to take any position they want . pico claimed that god desired a being capable of comprehending the beautiful and complicated universe he had created . this led to the creation of mankind , which he placed at the center of the universe with the ability to take whatever form he pleases . mankind , according to pico , could crawl down the chain and behave like an animal or crawl up the chain and behave like a god , it 's our choice . looking back at the sketch , we can see that by changing the position of the man , he can fill the irreconcilable areas of a circle and a square . if geometry is the language the universe is written in , then this sketch seems to say we can exist within all its elements . mankind can fill whatever shape he pleases geometrically and philosophically as well . in this one sketch , leonardo was able to combine the mathematics , religion , philosophy , architecture , and artistic skill of his age . no wonder it has become such an icon for the entire time period .
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because humans have a mortal body accompanied by an immortal soul , we divide the universe nicely in half . around the time leonardo sketched the vitruvian man , however , a neoplatonist named pico della mirandola had a different idea . he pried mankind off the chain and claimed that humans have a unique ability to take any position they want .
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the vitruvian man is named after
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translator : andrea mcdonough reviewer : bedirhan cinar pretty much everyone loves eating pizza , but it can be a messy business . pizza is soft and bendable . so how can you stop all that cheese from falling off ? you might know some tricks : you can use two hands -- not so classy , or you can use a paper plate and allow only the tip of the pizza to peek out . there 's one other trick , though : holding the crust , you can sort of fold the slice down the middle . now the tip of the pizza is n't falling over , and you can eat it without getting tomato sauce all over yourself or accidentally biting off some of that paper plate . but why should the tip stay up just because you bent the crust ? to understand this , you need to know two things : a little bit about the math of curved shapes and a little about the physics of thin sheets . first , the math . suppose i have a flat sheet made out of rubber . it 's really thin and bendable , so it 's easy to roll into a cylinder . i do n't need to stretch the sheet at all , just bend it . this property where one shape can be transformed into another without stretching or crumpling , is called isometry . a mathematician would say that a flat sheet is isometric to a cylinder . but not all shapes are isometric . if i try to turn my flat sheet into part of a sphere , there 's no way i can do it . you can check this for yourself , by trying to fit a flat sheet of paper onto a soccer ball without stretching or crumpling the paper . it 's just not possible . so a mathematician would say that a flat sheet and a sphere are n't isometric . there 's one more familiar shape that is n't isometric to any of the shapes we 've seen so far : a potato chip . potato chip shapes are n't isometric to flat sheets . if you want to get a flat piece of rubber into the shape of a potato chip , you need to stretch it -- not just bend it , but stretch it as well . so , that 's the math . not so hard , right ? now for the physics . it can be summed up in one sentence : thin sheets are easy to bend but hard to stretch . this is really important . thin sheets are easy to bend but hard to stretch . remember when we rolled our flat sheet of rubber into a cylinder ? that was n't hard , right ? but imagine how hard you 'd have pull on the sheet to increase its area by 10 percent . it would be pretty difficult . the point is that bending a thin sheet takes a relatively small amount of force , but stretching or crumbling a thin sheet is much harder . now , finally , we get to talk about pizza . suppose you go down to the pizzeria and buy yourself a slice . you pick it up from the crust , first , without doing the fold . because of gravity , the slice bends downwards . pizza is pretty thin , after all , and we know that thin sheets are easy to bend . you ca n't get it in your mouth , cheese and tomato sauce dripping everywhere -- it 's a big mess . so you fold the crust . when you do , you force the pizza into something like a taco shape . that 's not hard to do -- after all , this shape is isometric to the original pizza , which was flat . but imagine what would happen if the pizza were to droop down while you 're bending it . now it looks like a droopy taco . and what does a droopy taco look like ? a potato chip ! but we know that potato chips are not isometric to flat pieces of rubber or flat pizzas , and that means that in order to get into the shape it 's in now , the slice of pizza had to stretch . since the pizza is thin , this takes a lot of force , compared to the amount of force it takes to bend the pizza in the first place . so , what 's the conclusion ? when you fold the pizza at the crust , you make it into a shape where a lot of force is needed to bend the tip down . often gravity is n't strong enough to provide this force . that was kind of a lot of information , so let 's do a quick backwards recap . when pizza is folded at the crust , gravity is n't strong enough to bend the tip . why ? because stretching a pizza is hard . and to bend the tip downwards , the pizza would have to stretch , because the shape the pizza would be in , the droopy taco shape , is n't isometric to the original flat pizza . why ? because of math . as the pizza example shows , we can learn a lot by looking at the mathematical properties of different shapes . and it 's especially nice when those shapes happen to be pizza slices .
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a mathematician would say that a flat sheet is isometric to a cylinder . but not all shapes are isometric . if i try to turn my flat sheet into part of a sphere , there 's no way i can do it .
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which of the following shapes are isometric to each other :
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when i was in fourth grade , my teacher said to us one day : `` there are as many even numbers as there are numbers . '' `` really ? `` , i thought . well , yeah , there are infinitely many of both , so i suppose there are the same number of them . but even numbers are only part of the whole numbers , all the odd numbers are left over , so there 's got to be more whole numbers than even numbers , right ? to see what my teacher was getting at , let 's first think about what it means for two sets to be the same size . what do i mean when i say i have the same number of fingers on my right hand as i do on left hand ? of course , i have five fingers on each , but it 's actually simpler than that . i do n't have to count , i only need to see that i can match them up , one to one . in fact , we think that some ancient people who spoke languages that did n't have words for numbers greater than three used this sort of magic . for instance , if you let your sheep out of a pen to graze , you can keep track of how many went out by setting aside a stone for each one , and putting those stones back one by one when the sheep return , so you know if any are missing without really counting . as another example of matching being more fundamental than counting , if i 'm speaking to a packed auditorium , where every seat is taken and no one is standing , i know that there are the same number of chairs as people in the audience , even though i do n't know how many there are of either . so , what we really mean when we say that two sets are the same size is that the elements in those sets can be matched up one by one in some way . my fourth grade teacher showed us the whole numbers laid out in a row , and below each we have its double . as you can see , the bottom row contains all the even numbers , and we have a one-to-one match . that is , there are as many even numbers as there are numbers . but what still bothers us is our distress over the fact that even numbers seem to be only part of the whole numbers . but does this convince you that i do n't have the same number of fingers on my right hand as i do on my left ? of course not . it does n't matter if you try to match the elements in some way and it does n't work , that does n't convince us of anything . if you can find one way in which the elements of two sets do match up , then we say those two sets have the same number of elements . can you make a list of all the fractions ? this might be hard , there are a lot of fractions ! and it 's not obvious what to put first , or how to be sure all of them are on the list . nevertheless , there is a very clever way that we can make a list of all the fractions . this was first done by georg cantor , in the late eighteen hundreds . first , we put all the fractions into a grid . they 're all there . for instance , you can find , say , 117/243 , in the 117th row and 223rd column . now we make a list out of this by starting at the upper left and sweeping back and forth diagonally , skipping over any fraction , like 2/2 , that represents the same number as one the we 've already picked . we get a list of all the fractions , which means we 've created a one-to-one match between the whole numbers and the fractions , despite the fact that we thought maybe there ought to be more fractions . ok , here 's where it gets really interesting . you may know that not all real numbers -- that is , not all the numbers on a number line -- are fractions . the square root of two and pi , for instance . any number like this is called irrational . not because it 's crazy , or anything , but because the fractions are ratios of whole numbers , and so are called rationals ; meaning the rest are non-rational , that is , irrational . irrationals are represented by infinite , non-repeating decimals . so , can we make a one-to-one match between the whole numbers and the set of all the decimals , both the rationals and the irrationals ? that is , can we make a list of all the decimal numbers ? candor showed that you ca n't . not merely that we do n't know how , but that it ca n't be done . look , suppose you claim you have made a list of all the decimals . i 'm going to show you that you did n't succeed , by producing a decimal that is not on your list . i 'll construct my decimal one place at a time . for the first decimal place of my number , i 'll look at the first decimal place of your first number . if it 's a one , i 'll make mine a two ; otherwise i 'll make mine a one . for the second place of my number , i 'll look at the second place of your second number . again , if yours is a one , i 'll make mine a two , and otherwise i 'll make mine a one . see how this is going ? the decimal i 've produced ca n't be on your list . why ? could it be , say , your 143rd number ? no , because the 143rd place of my decimal is different from the 143rd place of your 143rd number . i made it that way . your list is incomplete . it does n't contain my decimal number . and , no matter what list you give me , i can do the same thing , and produce a decimal that 's not on that list . so we 're faced with this astounding conclusion : the decimal numbers can not be put on a list . they represent a bigger infinity that the infinity of whole numbers . so , even though we 're familiar with only a few irrationals , like square root of two and pi , the infinity of irrationals is actually greater than the infinity of fractions . someone once said that the rationals -- the fractions -- are like the stars in the night sky . the irrationals are like the blackness . cantor also showed that , for any infinite set , forming a new set made of all the subsets of the original set represents a bigger infinity than that original set . this means that , once you have one infinity , you can always make a bigger one by making the set of all subsets of that first set . and then an even bigger one by making the set of all the subsets of that one . and so on . and so , there are an infinite number of infinities of different sizes . if these ideas make you uncomfortable , you are not alone . some of the greatest mathematicians of cantor 's day were very upset with this stuff . they tried to make this different infinities irrelevant , to make mathematics work without them somehow . cantor was even vilified personally , and it got so bad for him that he suffered severe depression , and spent the last half of his life in and out of mental institutions . but eventually , his ideas won out . today , they 're considered fundamental and magnificent . all research mathematicians accept these ideas , every college math major learns them , and i 've explained them to you in a few minutes . some day , perhaps , they 'll be common knowledge . there 's more . we just pointed out that the set of decimal numbers -- that is , the real numbers -- is a bigger infinity than the set of whole numbers . candor wondered whether there are infinities of different sizes between these two infinities . he did n't believe there were , but could n't prove it . candor 's conjecture became known as the continuum hypothesis . in 1900 , the great mathematician david hilbert listed the continuum hypothesis as the most important unsolved problem in mathematics . the 20th century saw a resolution of this problem , but in a completely unexpected , paradigm-shattering way . in the 1920s , kurt gödel showed that you can never prove that the continuum hypothesis is false . then , in the 1960s , paul j. cohen showed that you can never prove that the continuum hypothesis is true . taken together , these results mean that there are unanswerable questions in mathematics . a very stunning conclusion . mathematics is rightly considered the pinnacle of human reasoning , but we now know that even mathematics has its limitations . still , mathematics has some truly amazing things for us to think about .
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i do n't have to count , i only need to see that i can match them up , one to one . in fact , we think that some ancient people who spoke languages that did n't have words for numbers greater than three used this sort of magic . for instance , if you let your sheep out of a pen to graze , you can keep track of how many went out by setting aside a stone for each one , and putting those stones back one by one when the sheep return , so you know if any are missing without really counting .
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some ancient languages did n't have words for numbers greater than three . what did the people who spoke those languages do when they needed to count their livestock ?
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maybe you 've recently seen the phrase `` gluten-free '' on food packaging , or take-out menus , shampoo bottles , apartment listings , the tag of your shirt , on a hammer , as a lower back tattoo , or in your friend 's resume . next time someone starts telling you about their newfound freedom from gluten , here are some questions you can ask , and the well-informed answers that your friend , being a reasonable individual making educated dietary choices , and by no means just following the latest diet craze , will tell you . what is gluten ? gluten is an insoluble protein composite made up of two proteins named gliadin and glutenin . where might you encounter gluten ? gluten is found in certain grains , particularly wheat , rye and barley . what has gluten been doing for the previous entirety of human history , and why do you suddenly care about it ? gluten is responsible for the elastic consistency of dough and the chewiness of foods made from wheat flour , like bread and pasta . for some people , these foods cause problems , namely wheat allergy , celiac disease , and non-celiac gluten sensitivity . wheat allergy is an uncommon condition that occurs when a person 's immune system mounts an allergic response to wheat proteins , leading to mild problems , and in rare cases , a potential dangerous reaction called anaphylaxis . celiac disease is an inherited disease , in which eating foods with gluten leads to inflammation and damage of the lining of the small intestine . this impairs intestinal function , leading to problems like belly pain , bloating , gas , diarrhea , weight loss , skin rash , bone problems like osteoporosis , iron deficiency , small stature , infertility , fatigue and depression . untreated , celiac disease increases the risk of developing certain types of cancer . celiac disease is present in one in every 100 to 200 persons in the u.s . when blood tests suggest the possibility of celiac , the diagnosis is confirmed with a biopsy . the most effective treatment is a gluten-free diet , which helps heal intestinal damage and improve symptoms . some people do n't have celiac disease or a wheat allergy , but still experience symptoms when they eat foods with gluten . these people have non-celiac gluten sensitivity . they experience painful gut symptoms and suffer from fatigue , brain fog , joint pain or skin rash . a gluten-free diet typically helps with these symptoms . so how many people actually have this gluten sensitivity you speak of ? gluten sensitivity 's occurrence in the general population is unclear , but likely much more common than wheat allergy or celiac disease . diagnosis is based on the development of symptoms , the absence of wheat allergy and celiac disease , and subsequent improvement on a gluten-free diet . there 's no reliable blood or tissue test , partly because gluten sensitivity is n't a single disease , and has a number of different possible causes . for example , it may be the case that gluten can activate the immune system in the small intestine , or cause it to become leaky . but sometimes , people claiming gluten sensitivity are actually sensitive not to wheat proteins , but sugars found in wheat and other foods , called fructans . the human intestine ca n't break down or absorb fructans , so they make their way to the large intestine or colon , where they 're fermented by bacteria , producing short-chain fatty acids and gases . this leads to unpleasant symptoms in some people with bowel problems . another possible explanation behind gluten sensitivity is the nocebo effect . this occurs when a person believes something will cause problems , and because of that belief , it does . it 's the opposite of the more well-known and much more fortuitous placebo effect . given how much bad press gluten is getting in the media , the nocebo response may play a role for some people who think they 're sensitive to gluten . for all these reasons , it 's clear that the problems people develop when they eat wheat and other grains are n't exclusively due to gluten . so a better name than non-celiac gluten sensitivty might be wheat intolerance .
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but sometimes , people claiming gluten sensitivity are actually sensitive not to wheat proteins , but sugars found in wheat and other foods , called fructans . the human intestine ca n't break down or absorb fructans , so they make their way to the large intestine or colon , where they 're fermented by bacteria , producing short-chain fatty acids and gases . this leads to unpleasant symptoms in some people with bowel problems . another possible explanation behind gluten sensitivity is the nocebo effect .
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the human intenstines can not break down or absorb fructans which leads to :
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the heisenberg uncertainty principle is one of a handful of ideas from quantum physics to expand into general pop culture . it says that you can never simultaneously know the exact position and the exact speed of an object and shows up as a metaphor in everything from literary criticism to sports commentary . uncertainty is often explained as a result of measurement , that the act of measuring an object 's position changes its speed , or vice versa . the real origin is much deeper and more amazing . the uncertainty principle exists because everything in the universe behaves like both a particle and a wave at the same time . in quantum mechanics , the exact position and exact speed of an object have no meaning . to understand this , we need to think about what it means to behave like a particle or a wave . particles , by definition , exist in a single place at any instant in time . we can represent this by a graph showing the probability of finding the object at a particular place , which looks like a spike , 100 % at one specific position , and zero everywhere else . waves , on the other hand , are disturbances spread out in space , like ripples covering the surface of a pond . we can clearly identify features of the wave pattern as a whole , most importantly , its wavelength , which is the distance between two neighboring peaks , or two neighboring valleys . but we ca n't assign it a single position . it has a good probability of being in lots of different places . wavelength is essential for quantum physics because an object 's wavelength is related to its momentum , mass times velocity . a fast-moving object has lots of momentum , which corresponds to a very short wavelength . a heavy object has lots of momentum even if it 's not moving very fast , which again means a very short wavelength . this is why we do n't notice the wave nature of everyday objects . if you toss a baseball up in the air , its wavelength is a billionth of a trillionth of a trillionth of a meter , far too tiny to ever detect . small things , like atoms or electrons though , can have wavelengths big enough to measure in physics experiments . so , if we have a pure wave , we can measure its wavelength , and thus its momentum , but it has no position . we can know a particles position very well , but it does n't have a wavelength , so we do n't know its momentum . to get a particle with both position and momentum , we need to mix the two pictures to make a graph that has waves , but only in a small area . how can we do this ? by combining waves with different wavelengths , which means giving our quantum object some possibility of having different momenta . when we add two waves , we find that there are places where the peaks line up , making a bigger wave , and other places where the peaks of one fill in the valleys of the other . the result has regions where we see waves separated by regions of nothing at all . if we add a third wave , the regions where the waves cancel out get bigger , a fourth and they get bigger still , with the wavier regions becoming narrower . if we keep adding waves , we can make a wave packet with a clear wavelength in one small region . that 's a quantum object with both wave and particle nature , but to accomplish this , we had to lose certainty about both position and momentum . the positions is n't restricted to a single point . there 's a good probability of finding it within some range of the center of the wave packet , and we made the wave packet by adding lots of waves , which means there 's some probability of finding it with the momentum corresponding to any one of those . both position and momentum are now uncertain , and the uncertainties are connected . if you want to reduce the position uncertainty by making a smaller wave packet , you need to add more waves , which means a bigger momentum uncertainty . if you want to know the momentum better , you need a bigger wave packet , which means a bigger position uncertainty . that 's the heisenberg uncertainty principle , first stated by german physicist werner heisenberg back in 1927 . this uncertainty is n't a matter of measuring well or badly , but an inevitable result of combining particle and wave nature . the uncertainty principle is n't just a practical limit on measurment . it 's a limit on what properties an object can have , built into the fundamental structure of the universe itself .
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the heisenberg uncertainty principle is one of a handful of ideas from quantum physics to expand into general pop culture . it says that you can never simultaneously know the exact position and the exact speed of an object and shows up as a metaphor in everything from literary criticism to sports commentary .
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the heisenberg uncertainty principle tells us that the structure of reality prevents us from knowing certain types of information at the same time . can you think of another example ( in physics or another field ) where it is impossible to know two sorts of information at the same time ? how does that case compare to the quantum situation described here ?
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when reverend jim jones founded the peoples temple in 1955 , few could have imagined its horrifying end . this progressive religious movement rose in popularity and gained support from some of san francisco 's most prominent politicians . but in 1977 , amidst revelations of brainwashing and abuse , jones moved with several hundred followers to establish the commune of jonestown in guyana . billed as a utopian paradise , the colony was more like a prison camp , and when a congressional delegation arrived to investigate its conditions , jones executed his final plan . on november 18 , 1978 , 909 men , women , and children died after being forced to drink poisoned flavor aid . that grizzly image has since been immortalized as shorthand slang for single-minded cult-like thinking , `` they drank the kool-aid . '' today , there are thousands of cults around the world . it 's important to note two things about them . first , not all cults are religious . some are political , therapy-based , focused on self-improvement , or otherwise . and on the flip side , not all new religions are what we 're referring to as cults . so what exactly defines our modern understanding of cults , and why do people join them ? broadly speaking , a cult is a group or movement with a shared commitment to a usually extreme ideology that 's typically embodied in a charismatic leader . and while few turn out as deadly as jonestown or heaven 's gate , which ended in a mass suicide of 39 people in 1997 , most cults share some basic characteristics . a typical cult requires a high level of commitment from its members and maintains a strict hierarchy , separating unsuspecting supporters and recruits from the inner workings . it claims to provide answers to life 's biggest questions through its doctrine , along with the required recipe for change that shapes a new member into a true believer . and most importantly , it uses both formal and informal systems of influence and control to keep members obedient , with little tolerance for internal disagreement or external scrutiny . you might wonder whether some of these descriptions might also apply to established religions . in fact , the world `` cultus '' originally described people who cultivated the worship of certain gods by performing rituals and maintaining temples . but in time , it came to mean excessive devotion . many religions began as cults , but integrated into the fabric of the larger society as they grew . a modern cult , by contrast , separates its members from others . rather than providing guidelines for members to live better lives , a cult seeks to directly control them , from personal and family relationships , to financial assets and living arrangements . cults also demand obedience to human leaders who tend to be highly persuasive people with authoritarian and narcissistic streaks motivated by money , sex , power , or all three . while a cult leader uses personal charisma to attract initial followers , further expansion works like a pyramid scheme , with early members recruiting new ones . cults are skilled at knowing whom to target , often focusing on those new to an area , or who have recently undergone some personal or professional loss . loneliness and a desire for meaning make one susceptible to friendly people offering community . the recruitment process can be subtle , sometimes taking months to establish a relationship . in fact , more than two-thirds of cult members are recruited by a friend , family member , or co-worker whose invitations are harder to refuse . once in the cult , members are subjected to multiple forms of indoctrination . some play on our natural inclination to mimic social behaviors or follow orders . other methods may be more intense using techniques of coercive persuasion involving guilt , shame , and fear . and in many cases , members may willingly submit out of desire to belong and to attain the promised rewards . the cult environment discourages critical thinking , making it hard to voice doubts when everyone around you is modeling absolute faith . the resulting internal conflict , known as cognitive dissonance , keeps you trapped , as each compromise makes it more painful to admit you 've been deceived . and though most cults do n't lead members to their death , they can still be harmful . by denying basic freedoms of thought , speech , and association , cults stunt their members ' psychological and emotional growth , a particular problem for children , who are deprived of normal developmental activities and milestones . nevertheless , many cult members eventually find a way out , whether through their own realizations , the help of family and friends , or when the cult falls apart due to external pressure or scandals . many cults may be hard to identify , and for some , their beliefs , no matter how strange , are protected under religious freedom . but when their practices involve harassment , threats , illegal activities , or abuse , the law can intervene . believing in something should not come at the cost of your family and friends , and if someone tells you to sacrifice your relationships or morality for the greater good , they 're most likely exploiting you for their own .
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the resulting internal conflict , known as cognitive dissonance , keeps you trapped , as each compromise makes it more painful to admit you 've been deceived . and though most cults do n't lead members to their death , they can still be harmful . by denying basic freedoms of thought , speech , and association , cults stunt their members ' psychological and emotional growth , a particular problem for children , who are deprived of normal developmental activities and milestones .
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why are cults potentially harmful for children ?
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have you ever daydreamed about traveling through time , perhaps fast forward in the centuries and seeing the distant future ? well , time travel is possible , and what 's more , it 's already been done . meet sergei krikalev , the greatest time traveler in human history . this russian cosmonaut holds the record for the most amount of time spent orbiting our planet , a total of 803 days , 9 hours , and 39 minutes . during his stay in space , he time traveled into his own future by 0.02 seconds . traveling at 17,500 miles an hour , he experienced an effect known as time dilation , and one day the same effect might make significant time travel to the future commonplace . to see why moving faster through space affects passage of time , we need to go back to the 1880s , when two american scientists , albert michelson and edward morley , were trying to measure the effect of the earth 's movement around the sun on the speed of light . when a beam of light was moving in the same direction as the earth , they expected the light to travel faster . and when the earth was moving in the opposite direction , they expected it to go slower . but they found something very curious . the speed of light remained the same no matter what the earth was doing . two decades later , albert einstein was thinking about the consequences of that never-changing speed of light . and it was his conclusions , formulated in the theory of special relativity , that opened the door into the world of time travel . imagine a man named jack , standing in the middle of a train carriage , traveling at a steady speed . jack 's bored and starts bouncing a ball up and down . what would jill , standing on the platform , see through the window as the train whistles through ? well , between jack dropping the ball and catching it again , jill would have seen him move slightly further down the track , resulting in her seeing the ball follow a triangular path . this means jill sees the ball travel further than jack does in the same time period . and because speed is distance divided by time , jill actually sees the ball move faster . but what if jack 's bouncing ball is replaced with two mirrors which bounce a beam of light between them ? jack still sees the beam dropping down and jill still sees the light beam travel a longer distance , except this time jack and jill can not disagree on the speed because the speed of light remains the same no matter what . and if the speed is the same while the distance is different , this means the time taken will be different as well . thus , time must tick at different rates for people moving relative to each other . imagine that jack and jill have highly accurate watches that they synchronize before jack boards the train . during the experiment , jack and jill would each see their own watch ticking normally . but if they meet up again later to compare watches , less time would have elapsed on jack 's watch , balancing the fact that jill saw the light move further . this idea may sound crazy , but like any good scientific theory , it can be tested . in the 1970s , scientists boarded a plane with some super-accurate atomic clocks that were synchronized with some others left on the ground . after the plane had flown around the world , the clocks on board showed a different time from those left behind . of course , at the speed of trains and planes , the effect is minuscule . but the faster you go , the more time dilates . for astronauts orbiting the earth for 800 days , it starts to add up . but what affects humans also affects machines . satellites of the global positioning system are also hurdling around the earth at thousands of miles an hour . so , time dilation kicks in here , too . in fact , their speed causes the atomic clocks on board to disagree with clocks on the ground by seven millionths of a second daily . left uncorrected , this would cause gps to lose accuracy by a few kilometers each day . so , what does all this have to do with time travel to the far , distant future ? well , the faster you go , the greater the effect of time dilation . if you could travel really close to the speed of light , say 99.9999 % , on a round-trip through space for what seemed to you like ten years , you 'd actually return to earth around the year 9000. who knows what you 'd see when you returned ? ! humanity merged with machines , extinct due to climate change or asteroid impact , or inhabiting a permanent colony on mars . but the trouble is , getting heavy things like people , not to mention space ships , up to such speeds requires unimaginable amounts of energy . it already takes enormous particle accelerators like the large hadron collider to accelerate tiny subatomic particles to close to light speed . but one day , if we can develop the tools to accelerate ourselves to similar speeds , then we may regularly send time travelers into the future , bringing with them tales of a long , forgotten past .
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well , the faster you go , the greater the effect of time dilation . if you could travel really close to the speed of light , say 99.9999 % , on a round-trip through space for what seemed to you like ten years , you 'd actually return to earth around the year 9000. who knows what you 'd see when you returned ? ! humanity merged with machines , extinct due to climate change or asteroid impact , or inhabiting a permanent colony on mars .
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if you traveled around space at 99.9999 % of the speed of light , for what seemed to you like 10 years , roughly what would be the year on earth when you got back ?
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hi there , i ’ m john green , this is crash course : world history and today we ’ re going to talk about islam , which like christianity and judaism grew up on the east coast of the mediterranean but unlike christianity and judaism is not terribly well understood in the west . for instance , you probably know what this is and what this is , you probably don ’ t know what that is . google it . mr. green mr. green why do you think people know so little about islamic history ? did you just ask an interesting non-annoying question , me from the past ? i think we don ’ t know about early islamic history because we don ’ t learn about it , me from the past , because we don ’ t learn about it , because we ’ re taught that our history is the story of christianity in europe , when in fact our history is the story of people on the planet , so let ’ s try to learn something today . [ theme music ] so in less than 200 years islam went from not existing to being the religious and political organizing principal of one of the largest empires in the world . and that story begins in the 7th century ce when the angel gabriel appeared to muhammad , a 40-ish guy who made his living as a caravan trader and told him to begin reciting the word of god . initially , this freaked muhammad out , as , you know , it would—but then his wife and a couple of other people encouraged him and slowly he came to accept the mantle as prophet . a few things to know about the world islam entered : first , muhammad ’ s society was intensely tribal . he was a member of the quraysh tribe , living in mecca and tribal ties were extremely important . also , at the time , the arabian peninsula was like this crazy religious melting pot . like most tribal arabs worshipped gods very similar to the mesopotamian gods you ’ ll remember from episode 3 . and by the time of muhammad , cult statutes of many of those gods had been collected in his hometown of mecca in this temple-like structure called the kaaba . but arabia was also a home for monotheisms like christianity and judaism , even a bit of zoroastrianism . so the message that there was only god wouldn ’ t have been like as surprising to muhammad as it was , for instance , to abraham . also , and this will become very important , the northern part of arabia was sandwiched between the byzantine empire and the persian sassanian empire—and you ’ ll remember , those guys were always fighting . they were like snowboarders and skiers , or like the westboro baptist church and everyone else . at its core , islam is what we call a radical reforming religion—just like jesus and moses sought to restore abrahamic monotheism after what they perceived as straying , so too did muhammad . muslims believe that god sent muhammad as the final prophet to bring people back to the one true religion , which involves the worship of , and submission to , a single and all-powerful god . the quran also acknowledges abraham and moses and jesus among others as prophets , but it ’ s very different from the hebrew and christian bibles : for one thing it ’ s much less narrative , but also its the written record of the revelations muhammad received—which means its not written from the point of view of people , it is seen as the actual word of god . the quran is a really broad-ranging text , but it returns again and again to a couple themes . one is strict monotheism and the other is the importance of taking care of those less fortunate than you . the quran , says of the good person spends his substance—however much he himself may cherish it—upon his near of kin , and the orphans , and the needy , and the wayfarer , and the beggars , and for the freeing of human beings from bondage . these revelations also radically increased the rights of women and orphans , which was one of the reasons why mohammad ’ s tribal leaders weren ’ t that psyched about them . to talk more about islamic faith and practice , let ’ s go to the thought bubble . the five pillars of islam are the basic acts considered obligatory , at least by sunni muslims . first is the shahada or the profession of the faith : there is no god but god and muhammad is god ’ s prophet , which is sometimes translated as “ there is no god but allah and muhammad is allah ’ s prophet ” , which tries to make muslims sound other and ignores the fact that the arabic word for god—whether you are christian or jewish or muslim—is allah . second , salat , or ritual prayer five times a day—at dawn , noon , afternoon , sunset , and late evening—which are obligatory unless you haven ’ t hit puberty , are too sick , or are menstruating . keep it pg , thought bubble . third , sawm , the month-long fast during the month of ramadan , in which muslims do not eat or drink or smoke cigarettes during daylight hours . since ramadan is a lunar-calendar month , it moves around the seasons , and obviously it ’ s most fun during the winter , when days are shorter , and least fun during the summer , when days are both long and hot . fourth is zakat , or almsgiving , in which non-poor muslims are required to give a percentage of their income to the poor , and lastly hajj , the pilgrimage to mecca that muslims must try to fulfill at least once in their lives , provided they are healthy and have enough money . and there ’ s also more to understanding islam than just knowing the quran . like judaism with its talmud , and christianity with its lives of saints and writings of church fathers , islam has supplementary sacred texts , chief among which is the hadith , a collection of sayings and stories about the prophet . thanks thought bubble . oh , it ’ s time for the open letter ? magic . an open letter to the 72 virgins . oh , but first let ’ s check what ’ s in the secret compartment . huh , it ’ s andre the giant . did you know that andre the giant died a virgin- is a fact that i made up ? dear 72 virgins , hey there , it ’ s me , john green . did you know that not all hadiths were created equal ? some sayings of the prophet are really well sourced . like for instance , a good friend or a relative heard the prophet say something and then it ended up as a hadith . but some hadiths are terribly sourced like , not to be irreverent , but some of it is like middle school gossip ; like rachel told rebekah that her sister ’ s brother ’ s friend kissed justin bieber on the face . and the vast majority of muslims don ’ t treat terribly sourced hadiths as scripture . and the idea that you go to heaven and get 72 virgins is not in the quran ; it ’ s in a terribly sourced hadith so it is my great regret to inform you , 72 virgins , that in the eyes of almost all muslims you do not exist . best wishes , john green one more thing about islam : like christianity and judaism , it has a body of law . you might have heard of it - it ’ s called sharia . although we tend to think of sharia as this single set of laws that all muslims follow , that ’ s ridiculous ; there are numerous competing interpretations of sharia , just as there are within any legal tradition . so people who embraced this worldview were called muslims , because they submitted to the will of god , and they became part of the umma , or community of believers . this would be a good moment for an uma thurman joke , but sadly she is no longer famous . i ’ m sorry if you ’ re watching this , uma thurman . being part of the umma trumped all other ties , including tribal ties , which got muhammad into some trouble and brings us , at last , back to history . so as muhammad ’ s following in mecca grew , the umma aroused the suspicion of the most powerful tribe , the quraysh . and it didn ’ t matter that muhammad himself was born into the quraysh tribe because he wouldn ’ t shut up about how there was only one god , which was really bad news to the quraysh tribe because they managed the pilgrimage trade in mecca , and if all those gods were false , it would be a disaster economically . —although come to think of it , in the end the meccan pilgrimage business turned out just fine . so the quraysh forced muhammad and his followers out of mecca in 622 ce , and they headed to yithrab , also known as medina . this journey , also know as the hijra , is so important that it marks year 0 in the islamic calendar . in medina , muhammad severed the religion ’ s ties to judaism , turning the focus of prayer away from jerusalem to mecca . also in medina , the islamic community started to look a lot more like a small empire than like a church . like , jesus never had a country to run . but muhammad did almost from the beginning . and in addition to being an important prophet , he was a good general and in 630 , the islamic community took back mecca . they destroyed the idols in the kabaa , and soon islam was as powerful a political force in the region as it was a religious one . and it ’ s because the political and religious coexisted from the beginning , that there ’ s no separate tradition of civic and religious law like there is in christianity and judaism . very different from judaism and even from christianity—which you ’ ll remember debated very different from judaism and even from christianity—which you ’ ll remember debated for generations whether to be inclusive . —and more importantly than separating islam from other monotheisms , that really separated islam from the tribalism in arabia . so then when muhammad died in 632 ce , there wasn ’ t a religious vacuum left behind : muhammad was the final prophet , the revelation of the quran would continue to guide the umma throughout their lives . but the community did need a political leader , a caliph . and the first caliph was abu bakr , muhammad ’ s father-in-law , who was not without his opponents : many people wanted ali , muhammad ’ s son-in-law , to lead the community . and although he did become the fourth caliph , that initial disagreement — to radically oversimplify because we only have ten minutes — began the divide between the two of the major sects of islam : suuni and shi ’ a . and even today , sunnis muslims believe abu bakr was rightly elected the first caliph and shi ’ a muslims believe it should ’ ve been ali . to sunnis , the first four caliphs—abu bakr , umar , uthman , and ali— are known as the rightly guided caliphs , and many of the conservative movements in the islamic world today are all about trying to restore the islamic world to those glory days , which—like most glory days—were not unambiguously glorious . abu bakr stabilized the community after muhammad ’ s death , and began the process of recording the quran in writing , and started the military campaigns against the byzantine and sassanian empires that within 116 years would allow the islamic empire to go from this to this . his successor umar was both an uncommonly good general and a brilliant administrator but like so many other great men , he proved terrible at avoiding assassination . which led to the caliphate of uthman , who standardized the quran and continued both his predecessor ’ s tradition of conquest and his predecessor ’ s tradition of getting assassinated . then ali finally got his turn at caliph , but his ascension was very controversial , and it ultimately led to a civil war . which eventually led to the emergence of uthman ’ s tribe , the umayyads , as the dynasty ruling over an ever-expanding islamic empire for more than a hundred years . it ’ s common to hear that in these early years islam quote spread by the sword , and that ’ s partly true , unless you are — wait for it — the mongols . actually , as usual , the truth is more complicated : many people , including the mongols but also including lots of people in central and east asia , embraced islam without any military campaigns . and in fact , the quran says that religion must not be an act of compulsion , but this much is true : the early islamic empire was really good at winning wars . and situated as they were between two very wealthy empires—the byzantines and the sassanians—there was plenty to fight for . first to fall was the sassanians , the last non-muslim successor to the persian empire . they were relatively easy pickings because they ’ d been fighting the byzantines for like 300 years and were super tired . also they ’ d been recently struck by plague . plague , man , i ’ m telling you ; it ’ s like the red tortoise shell of history . but in those early days they did pry away some valuable territory like egypt and the holy land and eventually they got into spain . where various muslim dynasties would entrench themselves until being expelled in 1492 . but as a good as they were at making war , it ’ s still tempting to chalk up the arabs ’ success to , you know , the will of god . and certainly a lot of the people they conquered felt that way . wars in this part of the world didn ’ t just pit people against each other , they also pitted their gods against each other . so while the islamic empire didn ’ t require its subjects to convert to islam , their stunning successes certainly convinced a lot of people that this monotheism thing was legit . once again , john green proving super hip to the slang of today ’ s young ’ ns . also , you paid lower taxes if you converted , and just as taxes on cigarettes lead to people not wanting to smoke , taxes on worshiping your idols lead to people not wanting to worship them anymore . so in a period of time that was , historically speaking , both remarkably recent and remarkably short , a small group of people from an area of the world with no natural resources managed to create one of the great empires of the world and also one of its great religions . and that very fact may be why people of western european descent remain largely ignorant about this period . not only were the muslims great conquerors , they spawned an explosion of trade and learning that lasted hundreds of years . they saved many of the classical texts that form the basis of the “ western canon ” while europe was ignoring them and they paved the way for the renaissance . while it ’ s important to remember that much of the world between spain and the indus river wasn ’ t arabized , most of it was so thoroughly islamized that these days we can ’ t think of the world we now call the middle east without thinking of it as islamic . perhaps the greatest testimony to islam ’ s power to organize peoples lives and their communities is that , in egypt , 5 times a day millions of people turn away from the pyramids and toward mecca . egypt , birthplace to one of the longest continuous cultures the world has ever known , is now the largest arab country in the world . next week we ’ ll talk about the dark ages . spoiler alert : they were darkest in the evening . thanks for watching and we ’ ll see you next time . crash course is produced and directed by stan muller , our script supervisor is danica johnson . the show is written by my high school history teacher raoul meyer and myself and our graphics team is thought bubble . last week ’ s phrase of the week was “ they might be giants ” . if you want to guess this week ’ s phrase of the week or suggest future ones you can do so in comments where you can also ask questions about today ’ s video that our team of historians will endeavor to answer . thank you so much for watching and as they say in my hometown , don ’ t forget to be awesome .
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and the idea that you go to heaven and get 72 virgins is not in the quran ; it ’ s in a terribly sourced hadith so it is my great regret to inform you , 72 virgins , that in the eyes of almost all muslims you do not exist . best wishes , john green one more thing about islam : like christianity and judaism , it has a body of law . you might have heard of it - it ’ s called sharia .
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after watching the video , identify some of the similarities and differences that exist between islam & other religions ( christianity , judaism , etc ) .
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translator : andrea mcdonough reviewer : jessica ruby welcome to the department of plagiarism investigation . the d.p.i . has dealt with numerous complex cases in their effort to bring plagiarists to justice and to rescue purloined texts . the first form of plagiarism that the d.p.i . regularly encounters is known as brain child snatching , in honor of the latin word , plagiarius , from which plagiarism originates . brain child snatchers sneak up on innocent papers and copy and paste them without citing any sources , putting quotation marks around direct quotes or changing a word . they 've also been known to steal and hold particularly eloquent essays for ransom . when brain child snatchers get together , they form a kidnapping ring , which involves brain child snatching from multiple sources . some perpetrators have even been known to commit self-plagiarism , one of the laziest crimes in the annals of the d.p.i . also known as one-sided collaborators , these odd balls snatch up entire texts or small passages that they 've written before and present them as brand-new material . brain child snatchers and kidnapping rings are easy for the d.p.i . to catch . just paste a few passages into a search engine , and bam ! they 're caught red-handed . the more covert forms of plagiarism include the wild goose chase technique , in which plagiarists create fake authors , book titles , page numbers , or other information in order to cover up plagiarism . and the old synonym switcheroo in which plagiarists utilize a thesaurus as their main weapon . by substituting a synonym for nearly every word in the document and leaving the sentence structure and order of the ideas the same , plagiarists give legitimate paraphrasing a very bad name . shoddy paraphrasing is also a key part of variations on a smokescreen , a technique in which multiple passages are paraphrased , then pasted together into one . the thorniest issue that the d.p.i . deals with is the misconception that you can never be accused of plagiarism if you use quotes and cite your sources . this is most certainly not the case because a paper that is made up of passage upon passage of other people 's ideas is known as a wholly quotable document . this is considered plagiarism since there are no original thoughts in the work . similarly , passage after passage of too closely paraphrased text from multiple cited sources is also plagiarism of the pervasively paraphrased kind because the ideas still are n't one 's own . and lastly , the technique of revealing while concealing is plagiarism because it involves selective amnesia regarding one 's sources in an attempt to cover up wholly quotable and pervasively paraphrased issues in a text . some passages are meticulously documented , quoted , or paraphrased , while others are presented entirely as one 's own . as you can see , the d.p.i . has its hands full , tackling all sorts of academic mischief and mayhem , ranging from the petty to the outrageous . given the gravity of these transgressions , you might be wondering why you 've never heard of the department of plagiarism investigation 's victories . that 's because it does n't technically exist . but people , like you and me , can be our own d.p.i . agents to fight plagiarism and uphold the values of original thinking . we know that the best defense against plagiarism consists of writers who save themselves time , worry , and effort by taking the far easier road of just doing the work themselves .
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to catch . just paste a few passages into a search engine , and bam ! they 're caught red-handed .
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type the phrase “ famous plagiarists ” into a search engine and read up on the various cases you find . which one is the most interesting to you and why ? write a paragraph or two describing the individual , the scandal , the consequences , and why this case interests you .
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hunger claws at your grumbling belly . it tugs at your intestines , which begin to writhe , aching to be fed . being hungry generates a powerful , often unpleasant physical sensation that 's almost impossible to ignore . after you 've reacted by gorging on your morning pancakes , you start to experience an opposing force , fullness , but how does your body actually know when you 're full ? the sensation of fullness is set in motion as food moves from your mouth down your esophagus . once it hits your stomach , it gradually fills the space . that causes the surrounding muscular wall to stretch , expanding slowly like a balloon . a multitude of nerves wrapped intricately around the stomach wall sense the stretching . they communicate with the vagus nerve up to the brainstem and hypothalamus , the main parts of the brain that control food intake . but that 's just one input your brain uses to sense fullness . after all , if you fill your stomach with water , you wo n't feel full for long . your brain also takes into account chemical messengers in the form of hormones produced by endocrine cells throughout your digestive system . these respond to the presence of specific nutrients in your gut and bloodstream , which gradually increase as you digest your food . as the hormones seep out , they 're swept up by the blood and eventually reach the hypothalamus in the brain . over 20 gastrointestinal hormones are involved in moderating our appetites . one example is cholecystokinin , which is produced in response to food by cells in the upper small bowel . when it reached the hypothalamus , it causes a reduction in the feeling of reward you get when you eat food . when that occurs , the sense of being satiated starts to sink in and you stop eating . cholecystokinin also slows down the movement of food from the stomach into the intestines . that makes your stomach stretch more over a period of time , allowing your body to register that you 're filling up . this seems to be why when you eat slowly , you actually feel fuller compared to when you consume your food at lightning speed . when you eat quickly , your body does n't have time to recognize the state it 's in . once nutrients and gastrointestinal hormones are present in the blood , they trigger the pancreas to release insulin . insulin stimulates the body 's fat cells to make another hormone called leptin . leptin reacts with receptors on neuron populations in the hypothalamus . the hypothalamus has two sets of neurons important for our feeling of hunger . one set produces the sensation of hunger by making and releasing certain proteins . the other set inhibits hunger through its own set of compounds . leptin inhibits the hypothalamus neurons that drive food intake and stimulates the neurons that suppress it . by this point , your body has reached peak fullness . through the constant exchange of information between hormones , the vagus nerve , the brainstem , and the different portions of hypothalamus , your brain gets the signal that you 've eaten enough . researchers have discovered that some foods produce more long-lasting fullness than others . for instance , boiled potatoes are ranked as some of the most hunger-satisfying foods , while croissants are particularly unsatisfying . in general , foods with more protein , fiber , and water tend to keep hunger at bay for longer . but feeling full wo n't last forever . after a few hours , your gut and brain begin their conversation again . your empty stomach produces other hormones , such as ghrelin , that increase the activity of the hunger-causing nerve cells in the hypothalamus . eventually , the growling beast of hunger is reawakened . luckily , there 's a dependable antidote for that .
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after you 've reacted by gorging on your morning pancakes , you start to experience an opposing force , fullness , but how does your body actually know when you 're full ? the sensation of fullness is set in motion as food moves from your mouth down your esophagus . once it hits your stomach , it gradually fills the space .
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what types of food are the most satisfying ?
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imagine two people are listening to music . what are the odds that they are listening to the exact same playlist ? probably pretty low . after all , everyone has very different tastes in music . now , what are the odds that your body will need the exact same medical care and treatment as another person 's body ? even lower . as we go through our lives , each of us will have very different needs for our own healthcare . scientists and doctors are constantly researching ways to make medicine more personalized . one way they are doing this is by researching stem cells . stem cells are cells that are undifferentiated , meaning they do not have a specific job or function . while skin cells protect your body , muscle cells contract , and nerve cells send signals , stem cells do not have any specific structures or functions . stem cells do have the potential to become all other kinds of cells in your body . your body uses stem cells to replace worn-out cells when they die . for example , you completely replace the lining of your intestines every four days . stem cells beneath the lining of your intestines replace these cells as they wear out . scientists hope that stem cells could be used to create a very special kind of personalized medicine in which we could replace your own body parts with , well , your own body parts . stem cell researchers are working hard to find ways in which to use stem cells to create new tissue to replace the parts of organs that are damaged by injury or disease . using stem cells to replace damaged bodily tissue is called regenerative medicine . for example , scientists currently use stem cells to treat patients with blood diseases such as leukemia . leukemia is a form of cancer that affects your bone marrow . bone marrow is the spongy tissue inside your bones where your blood cells are created . in leukemia , some of the cells inside your bone marrow grow uncontrollably , crowding out the healthy stem cells that form your blood cells . some leukemia patients can receive a stem cell transplant . these new stem cells will create the blood cells needed by the patient 's body . there are actually multiple kinds of stem cells that scientists can use for medical treatments and research . adult stem cells or tissue-specific stem cells are found in small numbers in most of your body 's tissues . tissue-specific stem cells replace the existing cells in your organs as they wear out and die . embryonic stem cells are created from leftover embryos that are willingly donated by patients from fertility clinics . unlike tissue-specific stem cells , embryonic stem cells are pluripotent . this means that they can be grown into any kind of tissue in the body . a third kind of stem cells is called induced pluripotent stem cells . these are regular skin , fat , liver , or other cells that scientists have changed to behave like embryonic stem cells . like embryonic stem cells , they , too , can become any kind of cell in the body . while scientists and doctors hope to use all of these kinds of stem cells to create new tissue to heal your body , they can also use stem cells to help understand how the body works . scientists can watch stem cells develop into tissue to understand the mechnanisms that the body uses to create new tissue in a controlled and regulated way . scientists hope that with more research , they can not only develop specialized medicine that is specific to your body but also better understand how your body functions , both when it 's healthy and when it 's not .
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using stem cells to replace damaged bodily tissue is called regenerative medicine . for example , scientists currently use stem cells to treat patients with blood diseases such as leukemia . leukemia is a form of cancer that affects your bone marrow .
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how are stem cells used to treat leukemia ? what other diseases might be treatable in this way ?
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yeah so neodymium is one my favourite f elements to work with . when you use it in compounds and you dissolve it , often you get colourful blue solutions from it . sometimes they are green as well , but often i have found that if concentration of the solution makes a really big difference to the colour of these solutions so you may have a compound which appears to be red but actually as you dilute it down eventually it ends up being blue , which is really pretty and sometimes if you cannula it from one flask to another and you can see through the cannula you can see it change colour as it goes through the cannula and then drops into the next solution again . so neodymium is one of the rare earths and it has a number of quite important applications . one of my favourite is in lasers , it ’ s used for example in this laser pointer and if you point the laser it makes this rather nice bright green colour . a little known use of neodymium is that the size and strength of volcanic eruptions can actually be judged from the composition of neodymium isotopes which are present . the first laser pointers were red . they didn ’ t use neodymium , and the green ones have become really quite fashionable among lecturers . so the way this works is that inside here there is a small crystal , of so-called neodymium yag , is the sum of the neodymium atoms that are isolated in the glass that contains yttrium and aluminium together to form so-called the g is for garnet , which describes the structure of the solid , and if you excite this the neodymium atoms can emit light in the infrared , like heat rays you can ’ t see them . and then further up here there is another crystal which turns this infrared light into green light so the green light comes out at the end . and also when neodymium is combined with iron and boron it can form a type of magnet which we call a ‘ permanent magnet ’ and it is extremely strong , one of the strongest that we actually know of . in order to get this doubling from the infrared to the green to work , you need to have pulses of light . so green lasers , although to the eye , look as if they are continuous are actually very rapid pulses which are very intense which is why these pointers are quite dangerous if you point them in the wrong direction in a lecture . because i wave my hands so much , i never use these in lectures . but i know that you the cameraman have also used… hello . …used neodymium , because neodymium is element number 60 and the cameraman ’ s future mother-in-law was 60 a few days ago and so we provided a sample of neodymium , element 60 , for him to present to her as a birthday present . happy birthday marion !
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yeah so neodymium is one my favourite f elements to work with . when you use it in compounds and you dissolve it , often you get colourful blue solutions from it . sometimes they are green as well , but often i have found that if concentration of the solution makes a really big difference to the colour of these solutions so you may have a compound which appears to be red but actually as you dilute it down eventually it ends up being blue , which is really pretty and sometimes if you cannula it from one flask to another and you can see through the cannula you can see it change colour as it goes through the cannula and then drops into the next solution again .
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which beautiful colors do the solutions of neodymium compounds display ?
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as you can see , i was born without fingers on my right hand . and also my right leg was several inches shorter than my left one . they broke the bones in the leg , then they screwed metal spikes into the bone . it has not only spikes , but wires that go all the way through the leg to stabilize it . i have to walk on it . i have to stretch it out so that my muscles do n't just get all atrophied . people always ask me , `` does it hurt ? '' yes , it does , but i focus on what i can do , not on what i can not do . i want to talk with you guys about overcoming obstacles . everybody has obstacles , a disability , a hurdle . we face a choice : let the obstacle overcome you or overcome the obstacle . maybe some of you have heard of jim abbott . he was a major league baseball player . he won a gold metal in the olympics . he played for the yankees , the angels . but he threw a no-hitter , and he only had one arm . when he was a kid , he came home mad one time and told his dad , `` the kids wo n't let me play baseball because i only have one hand . '' his dad replied , `` no , the kids wo n't let you play baseball because you stink at baseball . you ca n't change the fact that you only have one hand , but you can change the fact that you stink . '' so , his dad began to practice with him , and he got good . he overcame obstacles . teams would try to exploit his weak side . they would try to bunt to the side that he had a missing arm . but they never succeeded because he practiced and practiced fielding bunts to that side . there 's no dishonor in having a disability , and i wo n't let anyone diss my ability , but i do n't want anyone 's pity either . i will not use the obstacles i face as an excuse for having a pity party . i will practice harder , play harder , and push myself harder to keep getting better . last season i started on my varsity high school basketball team as a freshman , and i won rookie of the year . i was one of the top scorers on the team . one of the things that i find funny is that people judge me by appearance . they say , `` oh , look at this one-handed whitey with the limp . i do n't want him on my team ! '' but what they do n't know is that i do n't just have a disability , i have an ability . one of my favorite moments from this last season was we played a team that we had never played before . and when the game started , you could tell that they were dissing my disability . i mean , they double-teamed our tallest player . they just were playing really soft on me , and they just , you could tell they thought , `` what can this guy with one hand do ? '' so , they left me open for a three . i made that one . they left me open for another one . i made that one . then , they started to get frustrated , so they actually fouled me . i made both free throws . and they called time out . and as we were in the huddle , i could hear the other coach yelling at his players about me . they went from not covering me at all to double-teaming me . it 's all about overcoming obstacles . it 's true , i have a disability , but so do you . i also have an ability , so do you . everyone has obstacles to overcome . some are visible like mine . some are less visible . maybe your obstacle is that you come from a poor neighborhood . maybe people say you 'll never amount to anything . prove them wrong . maybe your obstacle is that you have a learning disability , and people think that you 're dumb . prove them wrong . maybe people judge you because of the color of your skin or your family background . prove them wrong . i know a lot of people who take one look at me and judge me . they say , `` oh , that kid ca n't be any good at basketball . one leg , one hand . '' if someone things you ca n't overcome the obstacles , prove them wrong .
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everybody has obstacles , a disability , a hurdle . we face a choice : let the obstacle overcome you or overcome the obstacle . maybe some of you have heard of jim abbott .
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steven also said that everyone has their own set of unique obstacles to overcome , some of which are obvious , while others are less apparent . what is a visible obstacle you must overcome ? how about a more obscure obstacle ?
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so how many of you have ever been in a cave before ? okay , a few of you . when you think of a cave , most of you think of a tunnel going through solid rock . in fact , that 's how most caves are . around this half of the country , most of your caves are made of limestone . back where i 'm from , most of our caves are made from lava rock because we have a lot of volcanoes out there . but the caves i want to share with you today are made completely of ice , specifically glacier ice as formed in the side of the tallest mountain in the state of oregon called mount hood . now , mount hood 's only one hour 's drive from portland , the largest city in oregon where over two million people live . now , the most exciting thing for a cave explorer is to find a new cave and be the first human to ever go into it . the second most exciting thing for a cave explorer is to be the first one to make a map of a cave . now , these days , with so many people hiking around , it 's pretty hard to find a new cave , so you can imagine how excited we were to find three new caves within sight of oregon 's largest city and realize that they have never been explored or mapped before . it was kind of like being an astronaut because we were getting to see things and go places that no one had ever seen or gone before . so , what is a glacier ? well , those of you that have ever seen or touched snow , you know that it 's really light because it 's just a bunch of tiny ice crystals clumped together and it 's mostly air . if you squish a handful of snow to make a snowball , it gets really small , hard , and dense . well , in a mountain like hood where it snows over twenty feet a year , it crushes the air out of it and gradually forms it into hard , blue ice . now , each year more and more ice stacks up on top of it and eventually gets so heavy that it starts to slide down the mountain under its own weight , forming a slow-moving river of ice . when an ice pack like that starts to move , we call it a glacier and we give it a name . the name of the glacier these caves were formed is the sandy glacier . now , each year as new snow lands on the glacier , it melts in the summer sun , and it forms little rivers of water on the flow along the ice and they start to melt and bore their way down through the glacier , forming big networks of caves , sometimes going all the way down to the underlying bedrock . now , the crazy thing about glacier caves is that each year new tunnels form , different waterfalls pop up or move around from place to place inside the cave . warm water from the top of the ice is boring its way down , and warm air from below the mountain actually rises up , gets into the cave , and melts the ceilings back taller and taller . but the weirdest thing about glacier caves is that the entire cave is moving because it 's formed inside a block of ice the size of a small city that 's slowly sliding down the mountain . now , this is brent mcgregor , my cave exploration partner . he and i have both been exploring caves a long time and we 've been climbing mountains a long time , but neither of us have ever really explored a glacier cave before . back in 2011 , brent saw a youtube video of a couple of hikers that stumbled across the entrance to one of these caves . there were no gps coordinates for it , and all we knew was that it was somewhere out on the sandy glacier . so , in july of that year , we went out on the glacier , and we found a big crack in the ice . we had to build snow and ice anchors , so we could tie off ropes and repel down into the hole . this is me looking into the entrance crevasse . at the end of this hole , we found a huge tunnel going right up the mountain underneath thousands of tons of glacier ice . we followed this cave back for about a half mile until it came to an end . and then with the help of our survey tools , we made a three-dimensional map of the cave on our way back out . so , how do you map a cave ? well , cave maps are n't like trail maps or road maps because they have pits and holes going to overlapping levels . to make a cave map , you have to set up survey stations every few feet inside the cave , and you use a laser to measure the distance between those stations . and you use a compass and an inclinometer to measure the direction the cave is headed and measure the slope of the floor and the ceilings . now , those of you taking trigonometry , that particular type of math is very useful for making maps like this because it allows you to measure heights and distances without actually having to go there . in fact , the more i mapped and studied caves , the more useful i found all that math that i originally hated in school to be . so , when you 're done surveying , you take all this data , you punch it into the computer , and you find someone that can draw really well , and you have them draft up a map that looks something like this . and it will show you both a bird 's eye view of the passage as well as a profile view of the passage , kind of like an ant farm view . we named this cave snow dragon cave because it was like a big dragon sleeping under the snow . now , later this summer as more snow melted off the glacier , we found more caves , and we realized they were all connected . not long after we mapped snow dragon , brent discovered this new cave not very far away . the inside of it was coated with ice so we had to wear big spikes in our feet called crampons , so we could walk around without slipping . this cave was amazing ! the ice in the ceiling was glowing blue and green because the sunlight from far above was shining through the ice and lighting it all up . now , we could n't understand why this cave was so much colder than snow dragon until we got to the end , and we found out why . there was a huge pit or shaft called a moulin going a 130 feet straight up to the surface of the glacier . cold air from the top of the mountain was flowing down this hole , blasting through the cave , freezing everything inside of it . and we were so excited about finding this new pit , we actually came back in january the following year so we could be the first ones to explore it . it was so cold outside , we actually had to sleep inside the cave . here 's our camp on the left side of this entrance room . the next morning we climbed out of the cave and hiked all the way to the top of the glacier where we finally rigged and repelled this pit for the very first time . brent named this cave pure imagination , i think , because the beautiful sights we saw in there were beyond what we could have ever imagined . so , besides really cool ice , what else is inside these caves ? well , not too much lives in them because they 're so cold , and the entrance is actually covered up with snow for about eight months of the year , but there are some really cool things in there . there 's weird bacteria living in the water that actually eat and digest rocks to make their own food to live under this ice . in fact , this past summer scientists collected samples of water and ice specifically to see if things called extremophiles , tiny lifeforms that have evolved to live in a completely hostile conditions , might be living under the ice , kind of like what they hope to find in the polar ice caps of mars some day . another really cool thing is that as seeds and birds land on the surface of the glacier and die , they get buried in the snow and gradually become part of the glacier , sinking deeper and deeper into the ice . as these caves form and melt their way up into the ice , they make these artifacts rain down from the ceiling and fall into the cave floor where we end up finding them . for example , this is a nodal first seed we found . it 's been frozen in ice for over a hundred years , and it 's just now starting to sprout . this mallard duck feather was found over 1800 feet in the back of snow dragon cave . this duck died on the surface of the glacier long , long ago , and its feathers have finally made it down through over a hundred feet of ice before falling inside the cave . and this beautiful quartz crystal was also found in the back of snow dragon . even now brent and i find it hard to believe that all these discoveries were essentially in our own backyard , hidden away just waiting to be found . like i said earlier , the idea of discovery in this busy world we live in kind of seems like something you can only do with space travel now , but that 's not true . every year new caves get discovered that no one has ever been in before . so , it 's actually not too late for one of you to become a discoverer yourself . you just have to be willing to look and go where people do n't often go and focus your eyes and your mind to recognize the discovery when you see it because it might be in your own backyard . thank you very much .
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the inside of it was coated with ice so we had to wear big spikes in our feet called crampons , so we could walk around without slipping . this cave was amazing ! the ice in the ceiling was glowing blue and green because the sunlight from far above was shining through the ice and lighting it all up .
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explain the process of mapping a cave .
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pretty much as long as humans have looked up at the night sky , we ’ ve been studying astronomy . in all this time , we ’ ve learned so much about the universe beyond our solar system , and have found lots of exoplanets orbiting other stars . but there ’ s a lot that scientists still don ’ t know . in fact , three relatively recent exoplanet discoveries are completely baffling researchers because , according to what we know about astronomy , they shouldn ’ t exist ! the first of these planets is called kepler-78b , which was discovered using data from nasa ’ s kepler space telescope , and orbits a star about 400 light years away from earth . based on changes in its star ’ s light , astronomers calculated that kepler-78b ’ s radius is about 1.2 times the radius of earth and it ’ s around 1.7 times as massive as the earth . this means it also has a similar density to the earth , so the researchers think its composition is similar , too , with lots of rock and iron . but that ’ s where the similarities stop . kepler-78b is about 100 times closer to its star than the earth is to the sun , and its surface temperatures might even get up to 3,100 kelvin . basically , it ’ s kind of like earth … if earth was a blazing inferno . this planet ’ s super close orbit to its host star means that a year only lasts 8.5 hours . and scientists don ’ t understand how kepler-78b even exists , because it doesn ’ t fit any of the current theories of planetary formation it ’ s just too close to its star . see , when kepler-78b was first forming from the gas and dust-filled protoplanetary disk , its host star was even larger . so if the planet was orbiting where it is now , it would ’ ve been inside its star , which is ... impossible . another option is that it formed farther away and migrated closer , but scientists think that ’ s pretty unlikely , since it probably would ’ ve kept going and plummeted into the star . as of now , it ’ s a mystery . the main thing we do know about kepler-78b is that it ’ ll probably only be around for another three billion years or so . it ’ ll move closer and closer to its host star , until the gravity eventually tears it apart . our next mysterious planet is called kepler-10c , which was also detected using data from the kepler space telescope , and is about 560 light years away from us . it ’ s radius isn ’ t all that special . it ’ s only about 2.3 times the radius of the earth . and initially , because of its size , scientists predicted that kepler-10c would have a thick , gaseous atmosphere , making it like a mini-neptune . instead , they found a planet with a mass that might be between 14-17 times the earth ’ s , which suggests that it ’ s a really dense rocky planet without much of an atmosphere . a mass that large is basically unheard of in a planet that size , which is why astronomers dubbed it a mega-earth . which , y ’ know , sounds pretty cool . based on our current understanding of planets , one this massive without an atmosphere shouldn ’ t even exist . theoretically , it would ’ ve grabbed a bunch of nearby lighter elements with its huge gravitational force as the star system was forming , and turned into a gas giant like jupiter . but it probably never even had an atmosphere , because if it did at some point , it would ’ ve held onto it . so , right now , scientists are just left with another giant rock in space that they can ’ t really explain . last but not least , we have a gas giant named hd 106906 b , which is 11 times as massive as jupiter , and discovered using data from the hubble space telescope and the magellan telescope in chile . this planet orbits a really young star 300 light years away from earth . the system is only 13 million years old . but that ’ s not what makes it weird . see , hd 106906 b orbits its star at a distance of 650 astronomical units . that ’ s more than 20 times the average distance between the sun and neptune . a planet that far away from its host star shouldn ’ t have had enough gaseous and rocky materials to grow that huge , especially in such a relatively short period of time . but , somehow , it exists . some researchers think it might have formed inside the dust-filled debris disk surrounding its host star , and got kicked out later , but they ’ re still not sure . a recent study seems to support this idea , suggesting that the planet might have even captured some of that dusty material , and might be surrounded by a ring or shroud . but that ’ s just one hypothesis and , until astronomers get more data , the planet is still an enigma . these three planets are just a drop in the bucket that is our universe , and we still have so much to learn . it ’ s really the strangest discoveries that make astronomy so cool . every time we start to think we understand how certain things work , like planetary formation , amazing surprises get thrown our way . thanks for watching this episode of scishow space , and a special thank you to all of our patrons on patreon . if you ’ d like to support more videos like this one , please go to patreon.com/scishow . and don ’ t forget to go to youtube.com/scishowspace and subscribe !
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the system is only 13 million years old . but that ’ s not what makes it weird . see , hd 106906 b orbits its star at a distance of 650 astronomical units . that ’ s more than 20 times the average distance between the sun and neptune .
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what makes hd 106906 b such a perplexing planet ?
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flying through the night , i watch over this world , a silent guardian , a watchful protector , a dark knight , i 'm ... okay , fine . so , i 'm not batman . i 'm just a bat . but like batman , i 'm often misunderstood . people think i 'm scary , strange and dangerous . if they only knew my story , though , i 'd be cheered as a hero . when people think of bats , many think of vampires who want to suck their blood . but the truth is that out of over 1200 bat species , only three are vampire bats . out of these three , only one prefers the blood of mammals , and even these bats mostly feed on cattle . maybe that still does n't seem so great , but vampire bats can be a great help to humans . a chemical known as desmoteplase found in vampire bat saliva helps break down blood clots , and is being tested by recovering stroke victims . of the remaining 1000+ species of bats , about 70 % feed on insects . these bats help control the real vampires : mosquitos , whose nasty bites are not just annoying but spread diseases , like west nile virus . a single little brown bat can eat 1000 insects every hour , and a colony of mexican free-tailed bats can eat several tons of moths in just one night . in the united states alone , bats provide an estimated 3.7 billion dollars worth of free pest control for farmers , which benefits everyone who eats the foods that they grow . fruit bats , also called megabats because of their large size , are important for the role they play in plant pollination . by traveling between flowers while feeding on nectar and fruits , these bats transport the pollen and seeds that help plants reproduce . in southeast asia , for example , the cave nectar bat is the only pollinator of the durian fruit . other bats pollinate peaches , bananas , and the agave plants that tequila is made from . without them , many of our food plants would be unable to produce the tasty fruits we enjoy . as heroes of the ecosystem , bats have their own unique utility belts . bats have been a source of inspiration for the design of flying robots and even an energy-efficient spy plane , as they are the only mammal capable of true powered flight . echolocation , a type of biological sonar , is also used by bats as a way to navigate and find prey in the dark . although there 's a common misconception that bats are blind , in truth , all species of bats have sight . and some have even adapted large eyes to see better in dim lighting . many people worry about getting infected by bats , and like any other animals , bats can carry diseases , like rabies . in reality , though , less than .5 % of all bats carry this virus . that 's about the same odds as getting the same result on a coin flip eight times in a row . the perception that bats are often diseased may come from the fact that sick bats , who may show unusual behavior , emerge during the daytime , or be unable to fly , are more likely to be encountered by people . so a good way to protect yourself is to protect bats as well , keeping them healthy , protecting their habitats , and reducing their risk of transmitting disease . in north america , bats are threatened by a devastating sickness called white-nose syndrome . this fungal infection causes bats to wake up while hibernating during a winter . unable to find food , they expend large amounts of energy , and eventually starve to death . white-nose syndrome has wiped out entire caves full of bats , with a mortality rate that can exceed 90 % . climate change and habitat destruction also pose serious threats to bat populations . for example , in january 2014 , a record heat wave in australia caused over 100,000 bats to die from heat exhaustion . some people just want to watch the world burn , and bats all over the world are threatened by damage to the places that we call home , including mangrove swamps , old-growth forests , and , of course , bat caves . so even though i 'm the hero of the story , i do need to be saved . and now that you know the true story about us bats , you can learn how to protect such heroic animals . install a properly designed bat box , one of the easiest ways to provide shelter for bats . discourage the use of pesticides , which can harm bats when we try to feed on the insects you want to get rid of in the first place . avoid going into caves where you might disturb hibernating bats , and always decontaminate your gear after visiting a cave . if you have unwanted bats living in an attic or barn , contact your local government to safely and humanely relocate us . and if you come across a bat , do not attempt to handle it , but instead , call animal control . batman might want to keep his identity secret , but a great way to help real bats is by continuing to learn about them and spreading the truth that they are real heroes , even if their good deeds are often unseen .
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so even though i 'm the hero of the story , i do need to be saved . and now that you know the true story about us bats , you can learn how to protect such heroic animals . install a properly designed bat box , one of the easiest ways to provide shelter for bats .
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which of these statements is true ?
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translator : andrea mcdonough reviewer : bedirhan cinar normally astronaut training takes about one full year , and it includes such subjects as astronomy , astrophysics , flight physiology , orbital trajectories , or orbital management . another part of the astronaut basic training is survival training . in the days of gemini , you never knew for sure where a spacecraft might land if there was an emergency , deorbit . so , we had to take desert training , water training , and jungle survival training . so , we had to learn how to cook and eat snake and all other , such other good things as that , and how to make water in a desert . after that year and a half of astronaut basic training , our names were all put on a list and that list was quite a bit longer at that time then there were seats available . and so , we were all given other duties to keep us occupied and to help continue our training . five of us were assigned to the lunar module , and our job was to be with these lunar modules as they were being built . so , we spent a lot of time there . i must admit that probably i had more time sleeping on the floor of lunar module # 6 than the crew who flew it on the moon . well , my next job was to be on the support crew of apollo 8 , and apollo 8 was the spacecraft that flew to the moon and came back but did not land . when they went behind the moon , they were supposed to do a thrusting maneuver to slow them down so they would be captured into lunar orbit . so we just had to sit and cool our heels when they went behind the moon , and we knew if they came out a little early on the other side , that they had not burned enough , not slowed down enough , and were going to skip out into space , they would n't be captured in orbit . if they came out a little bit late , it meant they had over-done it , and they were n't going to be in orbit , but were going to begin a spiral down to the lunar surface . and , of course , without a lunar module , that kind of ruins your whole day . you can imagine how relieved we were at the instant that they were supposed to appear on the other side of the moon that they appeared ! my next assignment was again a support crew assignment on apollo 12 , and apollo 12 was struck by lightning on its way off the pad . a nearby thunderstorm , there was a lightning bolt that went over and hit the very tip of the spacecraft . the charge went down through the spacecraft , through the booster , down the exhaust gases , and grounded out on the launching pad . it killed the electrical power system and the computers all died . you can imagine what it must have been like for them inside because suddenly the lights all went out and then they came back on when the batteries picked up the load . and , every single warning light and caution light in the spacecraft was on and flashing , and all the necessary bells , whistles , and buzzards and things that are in there , all were going off at the same time . the crew was totally confused as to what was going on . when we were settled in orbit , we tested all the various systems and everything looked good . so , that , now i figured this is it , and sure enough , i did get an assignment , a flight assignment . i was assigned to the back-up crew of apollo 16 , which meant that i was to be on the param crew of apollo 19 . and , several weeks into the training , nasa made the surprise announcment that they were going to cancel apollos 18 , 19 , and 20 . we were in the middle of the vietnam war , the budget was in bad shape , so you can imagine there were three very , very sad hangdog guys moping around the office because we lost our flight to the moon . but , several weeks later , i got a call from tom stafford , the senior astronaut at that time , and he wanted me in his office , and i went in , and he told me that he was sorry that i had missed my opportunity for the moon , but he said , `` i 've got another assignment for you . '' he said , `` i want you to be the commander of the third and final skylab mission . '' and , he said , `` do you think you could do the job ? '' and i said , `` of course , yes ! '' and , i 'll have to admit , a certain lump in my chest and in my stomach , because i was a rookie , and they normally do n't assign a rookie to be a commander , usually you have to have at least one flight under your belt , but they assigned me to that , which was really kind of a shock because the last rookie commander was neil armstrong on gemini 8 .
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when they went behind the moon , they were supposed to do a thrusting maneuver to slow them down so they would be captured into lunar orbit . so we just had to sit and cool our heels when they went behind the moon , and we knew if they came out a little early on the other side , that they had not burned enough , not slowed down enough , and were going to skip out into space , they would n't be captured in orbit . if they came out a little bit late , it meant they had over-done it , and they were n't going to be in orbit , but were going to begin a spiral down to the lunar surface .
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from 2001 : a space odyssey to star trek to documentaries on the largest nebulas and hypergiants , television creators and filmmakers are fascinated with space . what 's the fascination ? would you ever travel into space ?
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you know , i had a real rough time in school with add , and i have a phd . i earned a phd , but ... tough to pay attention -- biology , geology , physics , chemistry -- really tough for me . only one thing grabbed my attention , and it 's that planet called earth . but in this picture here , you 'll see that earth is mostly water . that 's the pacific . seventy percent of earth is covered with water . you can say , `` hey , i know earth . i live here . '' you do n't know earth . you do n't know this planet , because most of it 's covered with that -- average depth , two miles . and when you go outside and look up at the empire state building , chrysler building , the average depth of the ocean is 15 of those on top of one another . we 've explored about five percent of what 's in that water . `` explored , '' meaning , for the first time , go peek and see what 's there . so what i want to do today is show you some things about this planet , about the oceans . i want to take you from shallow water down to the deep water , and hopefully , like me , you 'll see some things that get you hooked on exploring planet earth . you know things like corals ; you 've seen plenty of corals , those of you who 've been to the beach , snorkeling , know corals are an amazing place to go -- full of life , some big animals , small animals , some nice , some dangerous , sharks , whales , all that stuff . they need to be protected from humanity . they 're great places . but what you probably do n't know is in the very deep part of the ocean , we have volcanic eruptions . most volcanoes on earth are at the bottom of the sea -- more than 80 percent . and we actually have fire , fire deep inside the ocean , going on right now . all over the world -- in the pacific , the atlantic , the indian ocean . in this place , the ocean floor , the rocks actually turn to liquid . so you actually have waves on the ocean floor . you 'd say nothing could live there , but when we look in detail , even there , in the deepest , darkest places on earth , we find life , which tells us that life really wants to happen . so , pretty amazing stuff . every time we go to the bottom of the sea , we explore with our submarines , with our robots , we see something that 's usually surprising , sometimes it 's startling and sometimes revolutionary . you see that puddle of water sitting there . and all around the water there 's a little cliff , there 's a little white sandy beach . we 'll get closer , you 'll see the beach a little bit better , some of the waves in that water , down there . the thing that 's special about this water is that it 's at the bottom of the gulf of mexico . so you 're sitting inside a submarine , looking out the window at a little pond of water beneath the sea . we see ponds , we see lakes , we see rivers -- in fact , right here is a river at the bottom of the ocean going from the lower left to the upper right . water is actually flowing through there . this totally blew our minds . how can you have this at the bottom ? you 're in the ocean looking at more water . and there 's animals that only live in that water . so , the bottom of the ocean -- i love this map , because it shows in the middle of the ocean , there 's a mountain range . it 's the greatest mountain range on earth , called the mid-ocean ridge -- 50,000 miles long , and we 've hardly had a peek at it . hardly had a peek at it . we find valleys , many thousands of valleys , larger , wider , deeper than the grand canyon . we find , as i said , underwater lakes , rivers , waterfalls . the largest waterfall on the planet is actually under the ocean , up near iceland . all that stuff is in that five percent that we 've explored . so the deal about the ocean is that to explore it , you 've got to have technology . not only technology , but it 's not just dave gallo or one person exploring , it 's a team of people . you 've got to have the talent , the team . you 've got to have the technology . in this case , it 's our ship , atlantis , and the submarine , alvin . inside that submarine -- this is an alvin launch -- there 's three people . they 're being wheeled out onto deck . there 's 47 other people , the teamwork on that ship , making sure that these people are okay . everybody in that submarine is thinking one thing right now : should i have gone to the bathroom one more time ? because you 're in there for 10 hours -- 10 hours in that little sphere . three of you together and nobody is going to be around you . you go into the water and once you hit the water , it 's amazing . there 's a lovely color blue that penetrates right inside you . you do n't hear the surface ship anymore , you hear that pinging of a sonar . if you 've got an iphone you 've got sonar on there -- it 's that same pinging that goes down to the bottom and comes back up . divers check out the sub to make sure the outside is okay , and then they say `` go , '' and down you go to the bottom of the ocean and it 's an amazing trip . so for two and a half hours , you sink down to the bottom . and two hours of it is totally pitch black . we thought that nothing could live inside that world at the bottom of the ocean . and when we look , we find some amazing things . all the way down -- we call it the mid-water -- from the top of the ocean down to the bottom , we find life . whenever we stop and look , we find life . i 'm going to show you some jellies . they 're absolutely some of the coolest creatures on earth . look at that thing , just flailing his arms around . that 's like a little lobster . that one is like all these animals with their mouths hooked together , the colonial animals . some animals are tiny , some can be longer than this stage . just amazing animals . and you ca n't collect them with a net -- we have to go with our cameras and take a look at them . so every time we go , new species of life . the ocean is full of life . and yet the deepest part of the ocean -- when we go to that mountain range , we find hot springs . now we were sure -- because this is poisonous water , because it 's so deep it would crush the titanic the same way you crush an empty cup in your hand -- we were sure there would be no life there at all . instead , we find more life and diversity and density than in the tropical rainforest . so , in one instance , in one peek out the window of the sub , we discover something that revolutionizes the way we think about life on earth ; and that is , you do n't always have to have sunlight to get life going . there 's big animals down there too , some that look familiar . that guy 's called dumbo . i love him . dumbo 's great . this guy -- oh man , i wish i had more footage of this . we 're trying to get an expedition together to go look at this and maybe in a year we 'll have that . go online and look . vampyroteuthis infernalis . the vampire squid . incredibly cool . in the darkness of the deep sea , he 's got glowing tentacles , so if i 'm coming at you like him , i put my arms out in the darkness so all you see are little glowing things over here . meanwhile , i 'm coming at you . when he wants to escape , he 's got these glowing pods on his butt that look like eyes . glowing eyes on his butt . how cool is that ? just an amazing animal . ( laughter ) `` vampire '' squid , because when it gets protective , it pulls this black cape over its whole body , and curls up into a ball . outrageous animal . this ship , `` the ship of dreams '' -- a hundred years ago this coming april , this ship was supposed to show up in new york . it 's the titanic . i co-led an expedition out there last year . we are learning so much about that ship . the titanic is an interesting place for biology , because animals are moving in to live on the titanic . microbes are actually eating the hull of the titanic . that 's where jack was king of the world there on the bow of the titanic . so we 're doing real good . and what 's exciting to me is that we 're making a virtual titanic , so you can sit there at home with your joystick and your headset on , and you can actually explore the titanic for yourself . that 's what we want to do , make these virtual worlds , so it 's not dave gallo or someone else exploring the world ; it 's you . you explore it for yourself . so here 's the bottom line : the oceans are unexplored and i ca n't begin to tell you how important that is , because they 're important to us . seven billion people live on this planet and all of us are impacted by the sea , because the oceans control the air you breathe , the water you drink , the food you eat . all those are controlled in some way by the ocean , and this is a thing that we have n't even explored -- five percent . the thing i want to leave you with is , in that five percent , i showed you some cool stuff . there 's a lot more cool stuff -- every dive we go on in the ocean , we find something new about the sea . so what 's in that other 95 percent ? did we get the exciting stuff or is there more out there ? and i 'm here to tell you that the ocean is full of surprises . there 's a quote i love by marcel proust : `` the true voyage of exploration is not so much in seeking new landscapes , '' which we do , `` but in having new eyes . '' and so i hope today , by showing you some of this , it 's given you some new eyes about this planet , and for the first time , i want you to think about it differently . thank you very much . thank you . ( applause )
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so every time we go , new species of life . the ocean is full of life . and yet the deepest part of the ocean -- when we go to that mountain range , we find hot springs . now we were sure -- because this is poisonous water , because it 's so deep it would crush the titanic the same way you crush an empty cup in your hand -- we were sure there would be no life there at all .
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why is it so surprising to find an abundance of living things in the deepest parts of the ocean ?
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homer 's `` odyssey '' , one of the oldest works of western literature , recounts the adventures of the greek hero odysseus during his ten-year journey home from the trojan war . though some parts may be based on real events , the encounters with strange monsters , terrifying giants and powerful magicians are considered to be complete fiction . but might there be more to these myths than meets the eye ? let 's look at one famous episode from the poem . in the midst of their long voyage , odysseus and his crew find themselves on the mysterious island of aeaea . starving and exhausted , some of the men stumble upon a palatial home where a stunning woman welcomes them inside for a sumptuous feast . of course , this all turns out to be too good to be true . the woman , in fact , is the nefarious sorceress circe , and as soon as the soldiers have eaten their fill at her table , she turns them all into animals with a wave of her wand . fortunately , one of the men escapes , finds odysseus and tells him of the crew 's plight . but as odysseus rushes to save his men , he meets the messenger god , hermes , who advises him to first consume a magical herb . odysseus follows this advice , and when he finally encounters circe , her spells have no effect on him , allowing him to defeat her and rescue his crew . naturally , this story of witchcraft and animal transformations was dismissed as nothing more than imagination for centuries . but in recent years , the many mentions of herbs and drugs throughout the passage have piqued the interest of scientists , leading some to suggest the myths might have been fictional expressions of real experiences . the earliest versions of homer 's text say that circe mixed baneful drugs into the food such that the crew might utterly forget their native land . as it happens , one of the plants growing in the mediterranean region is an innocent sounding herb known as jimson weed , whose effects include pronounced amnesia . the plant is also loaded with compounds that disrupt the vital neurotransmitter called acetylcholine . such disruption can cause vivid hallucinations , bizarre behaviors , and general difficulty distinguishing fantasy from reality , just the sorts of things which might make people believe they 've been turned into animals , which also suggests that circe was no sorceress , but in fact a chemist who knew how to use local plants to great effect . but jimson weed is only half the story . unlike a lot of material in the odyssey , the text about the herb that hermes gives to odysseus is unusually specific . called moly by the gods , it 's described as being found in a forest glen , black at the root and with a flower as white as milk . like the rest of the circe episode , moly was dismissed as fictional invention for centuries . but in 1951 , russian pharmacologist mikhail mashkovsky discovered that villagers in the ural mountains used a plant with a milk-white flower and a black root to stave off paralysis in children suffering from polio . the plant , called snowdrop , turned out to contain a compound called galantamine that prevented the disruption of the neurotransmitter acetylcholine , making it effective in treating not only polio but other disease , such as alzheimer 's . at the 12th world congress of neurology , doctors andreas plaitakis and roger duvoisin first proposed that snowdrop was , in fact , the plant hermes gave to odysseus . although there is not much direct evidence that people in homer 's day would have known about its anti-hallucinatory effects , we do have a passage from 4th century greek writer theophrastus stating that moly is used as an antidote against poisons . so , does this all mean that odysseus , circe , and other characters in the odyssey were real ? not necessarily . but it does suggest that ancient stories may have more elements of truth to them than we previously thought . and as we learn more about the world around us , we may uncover some of the same knowledge hidden within the myths and legends of ages passed .
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such disruption can cause vivid hallucinations , bizarre behaviors , and general difficulty distinguishing fantasy from reality , just the sorts of things which might make people believe they 've been turned into animals , which also suggests that circe was no sorceress , but in fact a chemist who knew how to use local plants to great effect . but jimson weed is only half the story . unlike a lot of material in the odyssey , the text about the herb that hermes gives to odysseus is unusually specific .
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why would a flower that can help stave off polio and alzheimer 's disease be of any use against jimson weed ?
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[ ♪sustained note♪ ] [ flag flapping in breeze ] [ path of freedom ] [ ♪ music ♪ ] [ prisoners chattering ] [ ♪ music ♪ ] - this is a tough guy world , and we have to control all of their movement and their behavior [ roberta richman - rhode island dept . of corrections ] because that 's the way you keep an institution safe for everybody who lives in it . [ ♪ music ♪ ] we have everybody here— murderers and rapists , sex offenders , drug addicts— everybody . [ 1 out of every 100 americans is currently behind bars ] my name is dennis . i 'm 52 years old . i 'm serving a 15-year sentence for assaulting my wife . my name is louis , 35 . i sold narcotics [ clears throat ] since i was about 13 or so . my name is juan . i 'm 34 years old . i 'm here for second degree murder . yeah . sadly , this is my charge . my name is celine . i 'm 39 . i 'll be 40 soon . i was given a life term . [ ♪ music ♪ ] a lot of times what lands people in prison [ fleet maull - prison mindfulness institute ] and what brings them back is a lack of good problem-solving skills and good communication skills . [ ♪ music ♪ ] [ richman ] fleet approached us asking if he could do some work in here . we were challenged . our union wanted to know how we could possibly bring an ex-offender in . [ maull ] i served 14½ years on a 25-year , no parole sentence . hello . [ ♪ music ♪ ] having served 14 years boosts his credibility— boosts his credibility with inmates . how 's your week been ? - it 's good . [ maull ] yeah ? good . what 's up ? yeah . hey . welcome . when i got locked up , i really hit a wall of just seeing the craziness of my life path up until then and the incredible selfish decisions i 'd been making . my son was 9 years old . he was going to grow up without his dad . and i was just so deeply full of remorse and regret that i just literally started practicing meditation like my hair was on fire . so i became extremely motivated to turn my life around . [ ♪ music ♪ ] and so i was living the life of this prison monk . [ ♪ music ♪ ] i was sourcing a meditation group twice a week in the chapel . [ ♪ music ♪ ] i started receiving letters from prisoners while i was in prison . i had published some articles ; people knew about me out in the world a little bit , and they started sending some of these letters to me thinking i would know what to do with them . i worked in the education department , and i had access to a copy machine . i would copy articles out of books , and i 'd put together a little thing and i 'd send it off to a prisoner . so it started off that way , and i decided it was a much bigger deal than i could do from my prison cells . i think we have a co-creative relationship with our life . we ca n't control other people , we do n't control life , but is there some relationship between what we put out and what comes back ? freedom before i came here was just another word . i had never been to prison before . all you know is what the media and the movies say about prison— `` take care of yourself , man . '' `` somebody 's going to try to take your manhood or something . '' you know what i mean ? i 'm thinking i 'm going to come in here and fight the world . [ maull ] in a prison like moran , there 's a serious conflict waiting around any corner . it 's an environment where people 's worst behaviors are just right there just under the surface . [ ♪ music ♪ ] when i first came in , i fought with officers , would beat up anyone , would do the unthinkable just because . [ dennis ] it 's a vicious cycle because once you come to prison your life just keeps tumbling , tumbling , tumbling , and it 's like a never-ending wall that wo n't stop building unless you find some way to get over that wall or at least in front of it . [ richman ] what circumstances did they have to survive on the street to bring them to where they are now ? do we want to save those lives , or do we want to discard them ? the crimes i committed , i brought shame to not only myself but to those who i love . so i 'm just really trying to do something to get out of that cycle . somebody 's given us an opportunity just to meditate and connect ourselves , and that 's golden . so sit up with that good posture , just rest your hands on your legs , and just take a moment to just feel . [ ♪ music ♪ ] [ richman ] i 've always thought that the people who survive are so much stronger than i could ever be . i asked fleet how he survived and thrived the way he has . he credits meditation for having given him the strength to live his life in prison and come out not as much the worse for wear as most people do . i do n't have a release date . so i can only go home when they decide i can . so i learned to live day by day , and that helped me to deal with prison , and i could only do that being in the moment , being in the now . [ ♪ music ♪ ] it 's like if i do n't like what 's going on , what can i do to shift it ? if i do n't like the relationship i have with my boss or with one of the cos or something , could i approach that person in a different way ? can i get creative about what i 'm doing to bring about a shift in the way things are— in other words , owning my own situation . so how do you resolve that ? i take a breath and then [ chuckles ] i step back . really , you have to . [ maull ] then suddenly get that there 's this whole thing there that they thought was who they are . that 's the only reality they knew . suddenly they get to step outside of that a little bit . you just see the lights go on . it 's like this sudden illumination . it 's like a mini enlightenment of sorts . and that 's very powerful . that 's what keeps me coming . the reality of it is i 'm living life , and meditation it has brought a new perspective in the way that it gave me like a tool to really look inside myself and change the way i am . [ richman ] people do n't understand the value of what they call the soft stuff , and i sometimes think without the soft stuff , no matter how much hard stuff you have , you 're bound to fail . you can live your life . you can be yourself . you can show others that this is n't a place to breed a better criminal ; this could actually be a place to breed a better person . you 're here because the way that you were did n't work . so why not be better ? [ prisoners chattering ] [ richman ] the people in prison are us . they 're not monsters . and more importantly , whether we want them to or not , they 're getting out . so do you want them to come out angrier and meaner and more dangerous than they were when they came in , or do you want to do whatever you can to change their behavior while they 're here ? we need people to see and experience prisoners stepping out of that culture and doing something transformative with their lives , and then people will start to have faith , people will see people coming back to their community and they realize these are human beings and that human beings ' lives have value and they 're not expendable . [ ♪ music ♪ ] [ this year 700,000 people will return home from prison ] [ ♪ music ♪ ] [ directed by emmanuel vaughan-lee , produced by dorothee royal-hedinger ] [ cinematography by elias koch , edited by adam loften , sound recording by emmanuel vaughan-lee ] [ music by h. scott salinas , sound mix by d. chris smith ] [ www.globalonenessproject.org ]
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it 's an environment where people 's worst behaviors are just right there just under the surface . [ ♪ music ♪ ] when i first came in , i fought with officers , would beat up anyone , would do the unthinkable just because . [ dennis ] it 's a vicious cycle because once you come to prison your life just keeps tumbling , tumbling , tumbling , and it 's like a never-ending wall that wo n't stop building unless you find some way to get over that wall or at least in front of it .
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if you were asked to rename this film , what title would you give it ?
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james joyce 's `` ulysses '' is widely considered to be both a literary masterpiece and one of the hardest works of literature to read . it inspires such devotion that once a year on a day called bloomsday , thousands of people all over the world dress up like the characters , take to the streets , and read the book aloud . and some even make a pilgrimage to dublin just to visit the places so vividly depicted in joyce 's opus . so what is it about this famously difficult novel that inspires so many people ? there 's no one simple answer to that question , but there are a few remarkable things about the book that keep people coming back . the plot , which transpires over the course of a single day , is a story of three characters : stephen dedalus , reprised from joyce 's earlier novel , `` a portrait of the artist as a young man '' ; leopold bloom , a half-jewish advertising canvasser for a dublin newspaper ; and bloom 's wife molly , who is about to embark on an affair . stephen is depressed because of his mother 's recent death . meanwhile , bloom wanders throughout the city . he goes to a funeral , his work , a pub , and so on , avoiding going home because molly is about to begin her affair . where it really starts to get interesting , though , is how the story 's told . each chapter is written in a different style . 15 is a play , 13 is like a cheesy romance novel , 12 is a story with bizarre , exaggerated interruptions , 11 uses techniques , like onomatopoeia , repetitions , and alliteration to imitate music , and 14 reproduces the evolution of english literary prose style , from its beginnings in anglo-saxon right up to the 20th century . that all culminates in the final chapter which follows molly 's stream of consciousness as it spools out in just eight long paragraphs with almost no punctuation . the range of styles joyce uses in `` ulysses '' is one of the things that makes it so difficult , but it also helps make it enjoyable . and it 's one of the reasons that the book has held up as one of the key texts of literary modernism , a movement characterized by overturning traditional modes of writing . joyce fills his narrative gymnastic routines with some of the most imaginative use of language you 'll find anywhere . take , for instance , `` the figure seated on a large boulder at the foot of a round tower was that of a broadshouldered deepchested stronglimbed frankeyed redhaired freelyfreckled shaggybearded widemouthed largenosed longheaded deepvoiced barekneed brawnyhanded hairlegged ruddyfaced sinewyarmed hero . '' here , joyce exaggerates the description of a mangy old man in a pub to make him seem like an improbably gigantesque hero . it 's true that some sections are impenetrably dense at first glance , but it 's up to the reader to let their eyes skim over them or break out a shovel and dig in . and once you start excavating the text , you 'll find the book to be an encyclopedic treasure trove . it 's filled with all manner of references and allusions from medieval philosophy to the symbolism of tattoos , and from dante to dublin slang . as suggested by the title , some of these allusions revolve around homer 's `` odyssey . '' each chapter is named after a character or episode from the `` odyssey , '' but the literary references are often coy , debatable , sarcastic , or disguised . for example , homer 's odysseus , after an epic 20-year-long journey , returns home to ithaca and reunites with his faithful wife . in contrast , joyce 's bloom wanders around dublin for a day and returns home to his unfaithful wife . it 's a very funny book . it has highbrow intellectual humor , if you have the patience to track down joyce 's references , and more lowbrow dirty jokes . those , and other sexual references , were too much for some . in the u.s. , the book was put on trial , banned , and censored before it had even been completed because it was originally published as a serial novel . readers of `` ulysses '' are n't just led through a variety of literary styles . they 're also given a rich and shockingly accurate tour of a specific place at a time : dublin in 1904 . joyce claimed that if dublin were to be destroyed , it could be recreated from the pages of this book . while such a claim is not exactly true , it does show the great care that joyce took in precisely representing details , both large and small , of his home city . no small feat considering he wrote the entire novel while living outside of his native ireland . it 's a testament to joyce 's genius that `` ulysses '' is a difficult book . some people find it impenetrable without a full book of annotations to help them understand what joyce is even talking about . but there 's a lot of joy to be found in reading it , more than just unpacking allusions and solving puzzles . and if it 's difficult , or frustrating , or funny , that 's because life is all that , and more . responding to some criticism of `` ulysses , '' and there was a lot when it was first published , joyce said that if `` ulysses '' is n't worth reading , then life is n't worth living .
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james joyce 's `` ulysses '' is widely considered to be both a literary masterpiece and one of the hardest works of literature to read . it inspires such devotion that once a year on a day called bloomsday , thousands of people all over the world dress up like the characters , take to the streets , and read the book aloud .
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stephen dedalus appears in which of joyce ’ s other works ?
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his face is recognized all over the world . the young medical student who became a revolutionary icon . but was che guevara a heroic champion of the poor or a ruthless warlord who left a legacy of repression ? order , order . hey , where have i seen that guy before ? ahem , your honor , this is ernesto che guevara . in the early 1950s , he left behind a privileged life as a medical student in argentina to travel through rural latin america . the poverty and misery he witnessed convinced him that saving lives required more than medicine . so he became a terrorist seeking to violently overthrow the region 's governments . what ? the region 's governments were brutal oligarchies . colonialism may have formally ended , but elites still controlled all the wealth . american corporations bought up land originally seized from indigenous people and used it for profit and export , even keeping most of it uncultivated while locals starved . could n't they vote to change that ? oh , they tried , your honor . in 1953 , che came to guatemala under the democratically-elected government of president árbenz . árbenz passed reforms to redistribute some of this uncultivated land back to the people while compensating the landowners . but he was overthrown in a cia-sponsored coup . the military was protecting against the seizure of private property and communist takeover . they were protecting corporate profits and che saw that they would use the fear of communism to overthrow any government that threatened those profits . so he took the lessons of guatemala with him to mexico . there , he met exiled cuban revolutionaries and decided to help them liberate their country . you mean help fidel castro turn a vibrant cuba into a dictatorship . dictatorship was what cuba had before the revolution . fulgencio batista was a tyrant who came to power in a military coup . he turned havana into a luxury playground for foreigners while keeping cubans mired in poverty and killing thousands in police crackdowns . even president kennedy called it the worst example of `` economic colonization , humiliation , and exploitation in the world . '' whatever batista 's faults , it ca n't compare to the totalitarian nightmare castro would create . forced labor camps , torture of prisoners , no freedom to speak or to leave . but this is n't the trial of fidel castro , is it ? che guevara was instrumental in helping castro seize power . as a commander in his guerilla army , he unleashed a reign of terror across the countryside , killing any suspected spies or dissenters . he also helped peasants build health clinics and schools , taught them to read , and even recited poetry to them . his harsh discipline was necessary against a much stronger enemy who did n't hesitate to burn entire villages suspected of aiding the rebels . let 's not forget that the new regime held mass executions and killed hundreds of people without trial as soon as they took power in 1959 . the executed were officials and collaborators who had tormented the masses under batista . the people supported this revolutionary justice . which people ? an angry mob crying for blood does not a democracy make . and that 's not even mentioning the forced labor camps , arbitrary arrests , and repression of lgbt people that continued long after the revolution . there 's a reason people kept risking their lives to flee , often with nothing but the clothes on their backs . so was that all this che brought to cuba ? just another violent dictatorship ? not at all . he oversaw land redistribution , helped established universal education , and organized volunteer literacy brigades that raised cuba 's literacy rate to 96 % , still one of the highest in the world . which allowed the government to control what information everyone received . guevara 's idealistic incompetence as finance minister caused massive drops in productivity when he replaced worker pay raises with moral certificates . he suppressed all press freedom , declaring that newspapers were instruments of the oligarchy . and it was he who urged castro to host soviet nuclear weapons , leading to the cuban missile crisis that brought the world to the brink of destruction . he was a leader , not a bureaucrat . that 's why he eventually left to spread the revolution abroad . which did n't go well . he failed to rally rebels in the congo and went to bolivia even when the soviets disapproved . the bolivian government , with the help of the cia , was able to capture and neutralize this terrorist in 1967 , before he could do much damage . while doing plenty of damage themselves in the process . so that was the end of it ? not at all . as che said , the revolution is immortal . he was publicly mourned in cities all over the world . not by the cubans who managed to escape . and his story would inspire young activists for generations to come . ha . a trendy symbol of rebellion for those who never had to live under his regime . symbols of revolution may become commodified , but the idea of a more just world remains . maybe , but i 'm not sharing my coffee . che guevara was captured and executed by government forces in bolivia . his remains would not be found for another 30 years . but did he die a hero or had he already become a villain ? and should revolutions be judged by their ideals or their outcomes ? these are the questions we face when we put history on trial .
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which allowed the government to control what information everyone received . guevara 's idealistic incompetence as finance minister caused massive drops in productivity when he replaced worker pay raises with moral certificates . he suppressed all press freedom , declaring that newspapers were instruments of the oligarchy .
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why was che ’ s tenure as finance minister unsuccessful ?
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there 's a lot of buzz in the news about de-extinction . with the growing interest in technologies and research , that could possibly bring animals and plants back from being , well , extinct . one of the candidates high on that list is the woolly mammoth . they 're the closest relatives to our living asian elephants today , and only widely disappeared about 10,000 years ago . with some isolated populations hanging on until about 4,700 years ago . that may seem like a long time , but at that period in the not-so-distant past , glass was being invented and the great pyramids of giza were being built . so , really , it 's a blip in the scheme of things . since woolly mammoth 's genetic information has been so well preserved in the permafrost , where recent specimens have been discovered , scientists have been able to sequence their genomes and now different groups are trying to figure out a way to insert mammoth genes into living elephant cells and maybe , in a way , bring them back . but my question is , why mammoths ? why not , say , mastodons ? no , not the heavy metal group , the late miocene megafauna . modern day elephants , mammoths and mastodons are all in the order proboscidea , along with other exinct tusked creatures , like palaeomastodons and gomphotheres . from the outside , mammoths and mastodons may look pretty similar , but they 've been different for a very long time . about 25 million years . mastodons were on earth long before the mammoths , who showed up a little late to the pleistocene party about 20 million years later . so you could n't hope to have good luck splicing mastodon dna into the asian elephant genome . that 's like putting human cells into a gibbon . it would n't work because the two are too genetically different . in addition to genetic differences between mammoths and mastodons , they 're also morphologically different . this is most obviously seen in their teeth . mammoths have large , flat , grinding surfaces on top of their molars , whereas mastodons have giant , mountain-like cusps . these cusps even inspired their scientific name , from the greek word `` masto '' for `` breast '' and `` odon '' for `` tooth . '' literally breast tooth . the shape of their teeth gives us clues about their diets , too . mammoths were grazers , like cows and elephants today and as such , they have flat grinding surfaces on their teeth for breaking down grasses . mastodons were browsers , like goats . the bulbous cusps on their teeth were useful for breaking down sticks and shrubs . so , remember , mammoths : cows . matsodons : breast-toothed goats . in addition to differences in their dentition , mastodons were shorter stockier than mammoths with smaller ears , but there were some exceptions . mammoths and mastodons are in two different genera , mammut and mammuthus . there were four different mastodon species and ten different species of mammoth . you 're probably most familiar with the woolly mammoth but there was also a pygmy species , the dwarf mammoth , which was about as tall as i am . this species was found on the channel islands off of california and its small size was most likely result of island dwarfism . this can happen when a large species gets isolated on an island , since smaller animals require fewer food resources , and in the absence of predators , small animals tend to breed more quickly than their larger counterparts . as to how they got to the island , how else ? they swam ! elephants today are great long-distance swimmers with their built-in snorkels and buoyant mass . smelling delicious grasses from mainland california , a group of columbian mammoths departed the coast , swimming out into the ocean towards the smell . fast forward 30,000 years and congratulations ! almost puppy sized mammoths . while there is n't yet a conclusive answer as to what caused the extinction for both mammoths and mastodons in the last 10,000 years , whether it was from over-hunting by humans or climate related changes , a few questions remain . if we can resurrect the mammoth genome , should we ? and where would we put them ?
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so , really , it 's a blip in the scheme of things . since woolly mammoth 's genetic information has been so well preserved in the permafrost , where recent specimens have been discovered , scientists have been able to sequence their genomes and now different groups are trying to figure out a way to insert mammoth genes into living elephant cells and maybe , in a way , bring them back . but my question is , why mammoths ?
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in order to 'bring back ' a woolly mammoth , researchers would splice their dna with dna from what animal ?
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( music ) on a typical day at school , endless hours are spent learning the answers to questions . but right now , we 'll do the opposite . we 're going to focus on questions where you ca n't learn the answers , because they 're unknown . i used to puzzle about a lot of things as a boy . for example , what would it feel like to be a dog ? do fish feel pain ? how about insects ? was the big bang just an accident ? and is there a god ? and if so , how are we so sure that it 's a he and not a she ? why do so may innocent people and animals suffer terrible things ? is there really a plan for my life ? is the future yet to be written , or is it already written and we just ca n't see it ? but then , do i have free will ? who am i , anyway ? am i just a biological machine ? but then , why am i conscious ? what is consciousness ? will robots become conscious one day ? i mean , i kind of assumed that some day i would be told the answers to all these questions . i mean , someone must know , right ? huh . guess what ? no one knows . most of those questions puzzle me more now than ever . but diving into them is exciting because it takes you to the edge of knowledge , and you never know what you 'll find there . so , two questions to kick off this series , questions that no one on earth knows the answer to ... text : how many universes are there ? why ca n't we see evidence of alien life ?
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but diving into them is exciting because it takes you to the edge of knowledge , and you never know what you 'll find there . so , two questions to kick off this series , questions that no one on earth knows the answer to ... text : how many universes are there ?
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of all the questions that anderson throws out there , which one is most intriguing to you , and why ?
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think about how your favorite stories hook you . `` when he was nearly 13 , my brother jim got his arm badly broken at the elbow . when it healed , and jim 's fears of never being able to play football were assuaged , he was seldom self conscious about his injury . '' `` all this happened , more or less . the war parts , anyway , are pretty much true . one guy i knew really was shot in dresden for taking a teapot that was n't his . '' `` my father 's family name being pirrip , and my christian name philip , my infant tongue could make of both names nothing longer or more explicit than 'pip . ' so i called myself pip , and came to be called pip . '' imagery , intrigue , emotion : each introduction makes you want to read more . if you have an assignment to write a literary analysis , your introduction will be just as important . there will be four elements in your essay : your introduction , thesis statement , analysis and conclusion . if you begin writing a literary analysis with the introduction , you may be discouraged . here 's a tip for writing a great introduction : write it last , and write your thesis first . figure out what you want to analyze before you actually analyze it . your thesis is the foundation for the rest of your essay , including your introduction . so how do you find your thesis ? start by asking questions . to charles dickens you may ask , `` why do you draw attention to characters ' hands ? '' `` what 's up with their names ? '' `` pumblechook ? really ? '' to narrow your concept for analysis , answer the questions yourself . `` estella ridicules pip 's hands , jaggers constantly washes his hands , pip insufferably burns his hands , mrs. joe brings pip up by hand . '' are there patterns in your answers ? `` estella 's comments smack of cruelty , while jaggers ' cleanses his immoral conscience . pip finds a second chance , while mrs. joe abuses a child under the guise of love and dedication . '' what can you analyze with this pattern ? `` hands symbolize social class inequities , and through dickens ' criticism , he exposes the dire need for reform in victorian london . what you will do next , which is an entirely different lesson , is to draft and revise your analysis . only after you write your analysis , return to your introduction . like authors earlier , try to intrigue and inspire your reader . avoid starting with famous quotations , dictionary definitions or rhetorical questions . consider the historical context of your topic , or an anecdote or some larger idea or concept . here 's an example : `` 27 bones in the hand and wrist allow humans to concurrently create and destroy . thousands of hands have been behind history 's astounding creations . hands represent a powerful symbol , one that was not lost on charles dickens . in great expectations , dickens uses hands to symbolize social class inequities , and through his criticism , he exposes the dire need for social reform in victorian london . '' take time crafting and revising your thesis and introduction . remember , if you are bored while writing , your reader will be bored while reading . by the way , did you notice the introduction to this lesson ? it did n't start with `` here 's how to write a thesis and introduction . '' would that have hooked you ?
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by the way , did you notice the introduction to this lesson ? it did n't start with `` here 's how to write a thesis and introduction . '' would that have hooked you ?
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you 've probably had to write something you did n't find enjoyable . what are some things that you can do to make writing a pleasurable experience ? have you ever read anything that you felt like a writer did n't want to write ? how did you know , and what advice would you give them to make sure this does n't happen again ?
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diabetes mellitus has been a scourge of the developed world with an estimated 400,000,000 people worldwide suffering from this disease , and 50 % more predicted within twenty years . its early symptoms , which include increased thirst and large volumes of urine , were recognized as far back as 1500 bce in egypt . while the term diabetes , meaning `` to pass through , '' was first used in 250 bce by the greek physician apollonius of memphis , type 1 and type 2 diabetes , associated respectively with youth and obesity , were identified as separate conditions by indian physicians somewhere in the 5th century ce . but despite the disease being known , a diagnosis of diabetes in a human patient would remain tantamount to a death sentence until the early 20th century , its causes unknown . what changed this dire situation was the help of humanity 's longtime animal partner : canis lupus familiaris , domesticated from grey wolves thousands of years ago . in 1890 , the german scientists von mering and minkowski demonstrated that removing a dog 's pancreas caused it to develop all the signs of diabetes , thus establishing the organ 's central role in the disease . but the exact mechanism by which this occurred remained a mystery until 1920 , when a young canadian surgeon named frederick banting and his student , charles best , advanced the findings of their german colleagues . working under professor macleod at the university of toronto , they confirmed that the pancreas was responsible for regulating blood glucose , successfully treating diabetic dogs by injecting them with an extract they had prepared from pancreas tissue . by 1922 , the researchers working with biochemist james collip were able to develop a similar extract from beef pancreas to first treat a 14-year-old diabetic boy , followed by six additional patients . the manufacturing process for this extract , now known as insulin , was eventually turned over to a pharmaceutical company that makes different types of injectable insulin to this day . banting and macleod received the nobel prize for medicine in 1923 for their discovery . but banting chose to share his portion with charles best , for his help in the initial studies involving dogs . but while medical experimentation on animals remains controversial , in this case at least , it was not just a matter of exploiting dogs for human needs . dogs develop diabetes at the rate of two cases per 1,000 dogs , almost the same as that of humans under 20 . most canine cases are of type 1 diabetes , similar to the type that young children develop following immune system destruction of the pancreas , and genetic studies have shown that the dog disease has many similar hallmarks of the human disease . this has allowed veterinarians to turn the tables , successfully using insulin to treat diabetes in man 's best friend for over 60 years . many dog owners commit to managing their dogs ' diabetes with insulin injected twice daily , regimented feedings , and periodic blood measurements using the same home-testing glucose monitors used by human patients . and if the purified pig insulin commonly used for dogs fails to work for a particular dog , the vet may even turn to a formulation of human insulin , bringing the process full circle . after all that dogs have done for us throughout the ages , including their role in a medical discovery that has saved countless human lives , using that same knowledge to help them is the least we could do .
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but banting chose to share his portion with charles best , for his help in the initial studies involving dogs . but while medical experimentation on animals remains controversial , in this case at least , it was not just a matter of exploiting dogs for human needs . dogs develop diabetes at the rate of two cases per 1,000 dogs , almost the same as that of humans under 20 . most canine cases are of type 1 diabetes , similar to the type that young children develop following immune system destruction of the pancreas , and genetic studies have shown that the dog disease has many similar hallmarks of the human disease .
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consider that humans and dogs can now be treated with recombinant expressed ( manufactured in a test tube ) insulin following molecular genetic sequencing . in light of this , have the need and the manner of animal experimentation become more refined over time ?
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when the next general election rolls around , who will be eligible to show up at the polls and vote for the president of the united states ? it 's really pretty simple . if you are at least 18 years old , a citizen of the u.s. , and a resident of a state , you can vote , assuming , that is , you are not a felon . seems about right . after all , the united states prides itself on being a democracy , or a government in which the ultimate authority lies with the citizens of the nation . but it was not always this way . in 1789 , george washington won the electoral college with 100 % of the vote , but whose vote was it ? probably not yours . only 6 % of the entire united states population was allowed to vote at all . voting was a right that only white , male property owners were allowed to exercise . by the 1820s and 1830s , the american population was booming from the east coast into the western frontier . frontier farmers were resilient , self-reliant , and mostly ineligible to vote because they did not own land . as these new areas of the nation became states , they typically left out the property requirement for voting . leaders such as andrew jackson , the united state 's first common man president , promoted what he called universal suffrage . of course , by universal suffrage , jackson really meant universal white , male suffrage . all he emphasized was getting rid of the property requirement for voting , not expanding the vote beyond white men . by the 1850s , about 55 % of the adult population was eligible to vote in the u.s. , much better than 6 % , but far from everybody . then , in 1861 , the american civil war began largely over the issue of slavery and states ' rights in the united states . when it was all over , the u.s. ratified the 15th amendment , which promised that a person 's right to vote could not be denied based on race , color , or previous condition as a slave . this meant that black men , newly affirmed as citizens of the u.s. , would now be allowed to vote . of course , laws are far from reality . despite the promise of the 15th amendment , intimidation kept african-americans from exercising their voting rights . states passed laws that limited the rights of african-americans to vote , including things like literacy tests , which were rigged so that not even literate african-americans were allowed to pass , and poll taxes . so , despite the 15th amendment , by 1892 , only about 6 % of black men in mississippi were registered to vote . by 1960 , it was only 1 % . and , of course , women were still totally out of the national voting picture . it was n't until 1920 that the women 's suffrage movement won their 30-year battle , and the 19th amendment finally gave women the vote , well , white women . the restrictions on african-americans , including african-american women , remained . after world war ii , many americans began to question the state of u.s. democracy . how could a nation that fought for freedom and human rights abroad come home and deny suffrage based on race ? the modern civil rights movement began in the 1940s with those questions in mind . after years of sacrifice , bloodshed , and pain , the united states passed the voting rights act of 1965 , finally eliminating restrictions such as literacy tests and protecting the voting rights promised under the 15th amendment to the constitution . now , any citizen over the age of 21 could vote . all seemed well until the united states went to war . when the vietnam war called up all men age 18 and over for the draft , many wondered whether it was fair to send men who could n't vote to war . in 1971 , the 26th amendment to the constitution made all citizens 18 and older eligible to vote , the last major expansion of voting rights in the united states . today , the pool of eligible voters in the u.s. is far broader and more inclusive than ever before in u.s. history . but , of course , it 's not perfect . there are still active efforts to suppress some groups from voting , and only about 60 % of those who can vote do . now that you know all the hard work that went into securing the right to vote , what do you think ? do enough citizens have the right to vote now ? and among those who can vote , why do n't more of them do it ?
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of course , laws are far from reality . despite the promise of the 15th amendment , intimidation kept african-americans from exercising their voting rights . states passed laws that limited the rights of african-americans to vote , including things like literacy tests , which were rigged so that not even literate african-americans were allowed to pass , and poll taxes . so , despite the 15th amendment , by 1892 , only about 6 % of black men in mississippi were registered to vote . by 1960 , it was only 1 % .
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list a few reasons why african-americans did not vote in the late 1800s even after the 15th amendment was ratified .
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so , i think all good tornado talks need to start with an awesome tornado shot . and this is not that awesome tornado shot . that was the first tornado i ever saw , it was really cool , really scary , and i 'm showing it to you guys because that 's why i got into the field in the first place . so even though it 's a bad photograph , it was really cool to be out there the first time . but now i 'm taking real tornado footage . fast forward a few years . this is a few years ago , during a field project called vortex2 , where myself and a bunch of other scientists were out there , surrounding tornadoes with different types of instrumentation and trying to figure out how tornadoes form . it 's a big question we 're trying to answer . it sounds like a very basic one , but it 's something we 're still trying to figure out . we 're also still trying to figure out what the winds are like near the surface . we know what the winds are like above building level , but we really do n't know what they 're like at the surface and how that relates to what we 're seeing above building level . most tornadoes form from what we call supercell thunderstorms . supercell thunderstorms are what you commonly think of as tornado-raising storms . they 're big , rotating thunderstorms that happen a lot of times in the midsection of the united states . but the problem is that even though they 're rotating up above , it does n't mean they 're rotating at the surface . and when we look at these storms and at these pictures and at the data we have , they all kind of look the same . and it 's really problematic if we 're trying to make tornado forecasts or warnings , because we only want to warn or forecast about the storms that are going to actually make a tornado . one of the big , critical distinguishing features , we think , between these storms , is something about the rear-flank downdraft . so these big rotating thunderstorms have this downdraft that wraps around the rear edge of it , hence the `` rear-flank '' downdraft . but we think how warm that is , how buoyant that air is , and then also how strong the updraft it 's wrapping into , makes a big difference on whether or not it 's going to make a tornado . there 's a lot more that goes into it -- i 'll tell you about that in a second . once you actually get a tornado , again , the problem that we have is getting measurements near the surface . it 's really hard to get measurements near the surface -- most people do n't want to drive into tornadoes . there are a few exceptions ; you might have seen them on tv shows . but most people do n't want to do that . even getting instrumentation in the path of the tornado is pretty tricky , too . because , again , you do n't want to be that close to a tornado because sometimes the winds around the tornado are strong as well . so getting information , that critical location , is key for us because , again , we do n't know if the winds that we 're seeing above ground level , way above building level , actually map to the surface , if they 're stronger , weaker , or about the same as what we 're seeing above buildings . the way we get at answering a lot of these questions -- and i 'm an observationalist ; i love to get out in the field , and collect data on tornadoes -- we compile a lot of observations . i work with this group who operates mobile radars , and they 're exactly what they say -- basically , a radar on the back of a big blue truck , and we drive up really close to tornadoes to map out the winds . we map out the precipitation . we map out all these different things that are going on in order to better understand the processes in these storms . and that bottom there , that 's what a tornado looks like when you 're looking at it with a mobile radar , and really close . also , what we do is a lot of modeling , so we do a lot of computer models and simulations , because the atmosphere is governed by the laws of physics . so we can model the laws of physics and see where the tornado might go , where the storm might go , how strong the winds are near the surface and not actually have to go out in the field . but of course , we want to have both observations and modeling to move forward with the science . so , i showed you that video earlier that went real quick , too . this is what it looks like , looking at it with a radar . so you saw it visually , but this is what i get really excited about when i see now in the field , stuff that looks like this . the really exciting thing about looking at stuff like this is that we caught this storm from when it did n't make a tornado to when it made a tornado and intensified and when it dissipated . this is the one of the rare data sets that we have out there that were able to study the entire life cycle of a tornado . i talked about how we think that rear-flank downdraft is important because it tilts , there 's a lot of spin in the atmosphere , but the problem with all this spin in the atmosphere is it needs to be oriented vertically , because that 's what tornadoes are doing , and it needs to orientated vertically near the ground . so we think this rear-flank downdraft just pulses . and these pulses in this rear-flank downdraft , we think , are very important for converging that rotation , but also getting that rotation into the right place . other things we 've learned is that we have gotten a bunch of fortuitous measurements in the path of the tornadoes and very near the surface . and we found out that the winds near the surface are actually pretty comparable to what we 're seeing 30 , 40 meters above ground level . so there 's not a big reduction in what we 're seeing above the surface to what we 're seeing at house level . and that was a pretty surprising finding for us , because we kind of assumed that the winds decrease pretty substantially near the surface . i 'm going to end with this real quick . and this is not my last tornado i ever saw , but i really like this image , because this was taken with one of those mobile radars i was talking about . this is a tornado , not a hurricane , and this is what it looks like when you 're really close to it . and i find this amazing , that we can actually take technology this close to these types of storms and see these inner workings . and for those of you who look at tornado images often , you can see there 's a lot going on -- there 's rain spiraling , and you can actually see the debris cloud associated with this tornado . i look forward to the future and future technologies and being able to learn a lot more about these storms , as the world advances , as you guys contribute to the science and we 're able to really learn more about how tornadoes form . thank you . ( applause )
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so , i think all good tornado talks need to start with an awesome tornado shot . and this is not that awesome tornado shot . that was the first tornado i ever saw , it was really cool , really scary , and i 'm showing it to you guys because that 's why i got into the field in the first place .
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compare and contrast how hurricane and tornadoes get their intensity ratings . what are the deficiencies in tornado intensity ratings ? what are some possible solutions ?
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what do charles darwin , michael jordan , and yoda have in common ? they , like many other historical and fictive individuals , are bald , in some cases by their own choice . for centuries , a shining dome has been a symbol of intelligence , but despite this , many balding people still wish their hair would return . scientists have long pondered , `` why do some people lose their hair , and how can we bring it back ? '' the full-headed among us have about 100,000 to 150,000 hairs on our scalps , and scientists have discovered two things about this dense thicket . firstly , the sprouting hair we see is mostly made up of keratin , the protein leftover from dead cells that are forced upwards as new cells grow beneath them . secondly , the structures that drive hair growth are called hair follicles , a network of complex organs that forms before we 're born , and grows hair in an everlasting cycle . this cycle has three main phases . the first is anagen , the growth phase , which up to 90 % of your hair follicles are experiencing right now , causing them to push up hair at a rate of one centimeter per month . anagen can last for two to seven years , depending on your genes . after this productive period , signals within the skin instruct some follicles to enter a new phase known as catagen , or the regressing stage , causing hair follicles to shrink to a fraction of their original length . catagen lasts for about two to three weeks and cuts blood supply to the follicle , creating a club hair , meaning it 's ready to be shed . finally , hairs enter telogen , the resting phase , which lasts for ten to twelve weeks , and affects about 5-15 % of your scalp follicles . during telogen , up to 200 club hairs can be shed in a day , which is quite normal . then , the growth cycle begins anew . but not all heads are hairy , and , in fact , some of them grow increasingly patchy over time in response to bodily changes . 95 % of baldness in men can be attributed to male pattern baldness . baldness is inherited , and in people with this condition , follicles become incredibly sensitive to the effects of dihydrotestosterone , a hormonal product made from testosterone . dht causes shrinkage in these overly sensitive follicles , making hair shorter and wispier . but loss is n't sudden . it happens gradually , along a metric known as the norwood scale , which describes the severity of hair loss . first , hair recedes along the temples , then hair on the crown begins to thin in a circular pattern . at the highest rating on the scale , these balding areas meet and expand dramatically , eventually leaving only a ring of sparse hair around the temples and the back of the head . genetics is n't all that drives hair loss . long periods of stress can release signals that shock follicles and force them into the resting phase prematurely . some women experience this after childbirth . follicles might also lose the ability to go into anagen , the growth phase . people going through chemotherapy treatment temporarily experience this . but while balding may look permanent , scientific investigation has revealed the opposite . below the skin 's surface , the roots that give rise to our hair actually remain alive . using this knowledge , scientists have developed drugs that shorten the resting phase , and force follicles into anagen . other drugs combat male pattern baldness by blocking the conversion of testosterone to dht so that it does n't affect those sensitive follicles . stem cells also play a role in regulating the growth cycle , and so scientists are investigating whether they can manipulate the activity of these cells to encourage follicles to start producing hair again . and in the meantime , while scientists hone their hair-reviving methods , anyone going bald , or considering baldness , can remember that they 're in great company .
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catagen lasts for about two to three weeks and cuts blood supply to the follicle , creating a club hair , meaning it 's ready to be shed . finally , hairs enter telogen , the resting phase , which lasts for ten to twelve weeks , and affects about 5-15 % of your scalp follicles . during telogen , up to 200 club hairs can be shed in a day , which is quite normal .
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which of the following hair phase ( s ) is known as the 'resting phase ' marked by shedding of club hairs ?
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how many times can you fold a piece of paper ? assume that one had a piece of paper that was very fine , like the kind they typically use to print the bible . in reality , it seems like a piece of silk . to qualify these ideas , let 's say you have a paper that 's one-thousandth of a centimeter in thickness . that is 10 to the power of minus three centimeters , which equals .001 centimeters . let 's also assume that you have a big piece of paper , like a page out of the newspaper . now we begin to fold it in half . how many times do you think it could be folded like that ? and another question : if you could fold the paper over and over , as many times as you wish , say 30 times , what would you imagine the thickness of the paper would be then ? before you move on , i encourage you to actually think about a possible answer to this question . ok. after we have folded the paper once , it is now two thousandths of a centimeter in thickness . if we fold it in half once again , the paper will become four thousandths of a centimeter . with every fold we make , the paper doubles in thickness . and if we continue to fold it again and again , always in half , we would confront the following situation after 10 folds . two to the power of 10 , meaning that you multiply two by itself 10 times , is one thousand and 24 thousandths of a centimeter , which is a little bit over one centimeter . assume we continue folding the paper in half . what will happen then ? if we fold it 17 times , we 'll get a thickness of two to the power of 17 , which is 131 centimeters , and that equals just over four feet . if we were able to fold it 25 times , then we would get two to the power of 25 , which is 33,554 centimeters , just over 1,100 feet . that would make it almost as tall as the empire state building . it 's worthwhile to stop here and reflect for a moment . folding a paper in half , even a paper as fine as that of the bible , 25 times would give us a paper almost a quarter of a mile . what do we learn ? this type of growth is called exponential growth , and as you see , just by folding a paper we can go very far , but very fast too . summarizing , if we fold a paper 25 times , the thickness is almost a quarter of a mile . 30 times , the thickness reaches 6.5 miles , which is about the average height that planes fly . 40 times , the thickness is nearly 7,000 miles , or the average gps satellite 's orbit . 48 times , the thickness is way over one million miles . now , if you think that the distance between the earth and the moon is less than 250,000 miles , then starting with a piece of bible paper and folding it 45 times , we get to the moon . and if we double it one more time , we get back to earth .
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how many times do you think it could be folded like that ? and another question : if you could fold the paper over and over , as many times as you wish , say 30 times , what would you imagine the thickness of the paper would be then ? before you move on , i encourage you to actually think about a possible answer to this question .
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paenza asks how thick the paper would be after 30 folds , and the answer is
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global oneness project a game for life i do n't know how i can really put this , but my football is really something that is very powerful in my life , that gives me the drive to be who i am now , and have the goals i have now . i think if it was n't for football… i ca n't really imagine myself without football . certain things , certain principles in my life are based on my football . i do n't know if you understand what i mean . [ ♪ native music ♪ ] [ children playing ] [ ♪ native music ♪ ] this is my place . its a very small place . its just a four room house . this is where we sit as a family , watch tv , eat supper , and chat . just family chats . i 'll show you the kitchen where we cook our dinner . this is my kitchen . its not a very big place but it is where i live . this is my bedroom ; i share it with my aunt , but unfortunately now she is asleep because she was working night shift . this is my bed . i sleep here with my kitten . oh yes , this is my kitten . it is my friend . i sleep with her almost every night . this is my aunt . she stays here . she is selling veggies and fruit and her business is definitely going very well . in one week you find that you come and buy something and then its not there , its finished . so she 's got a business that is doing well . this road that we are walking on , this is where i started playing soccer when i got to port elizabeth . we put small stones , there would be goals on each side of the road , then we 'd be playing with the guys . that was before there was grass here . there was no grass here , so we would play from that wall to this side of the road . i grew up playing here and when i see this road or when i walk here i always remember where i started playing soccer . [ ♪ native music ♪ ] most of the time i was with my other two cousin-brothers , and they would spend most of their time playing soccer and that 's how i got on to the field and played as well . [ ♪ native music ♪ ] when i was growing up i was very , very poor . when i was still in primary school , i would wash with cold water . my school shoes , the sole was broken , so when it was raining , my socks would be so wet . and in terms of food , there was absolutely nothing to eat . [ ♪ native music ♪ ] for me to be able to eat at school i would have to wait until we are writing a test . then each pupil would put on 10 cents or 20 cents . then the whole amount would go to the person who was the highest on a test , and that is how i would manage to eat , because , if we were writing a test and put on some money , it was definitely my money because i was a very good student . [ ♪ native music ♪ ] i know their are many people out there who are going through what i went through . i know they wo n't deal with it the way i dealt with it , because i was taking everyday as it was coming . [ ♪ native music ♪ ] i never thought of going out and being a prostitute or something , and i know other people who are going through that thing . always , not always , but sometimes opt for that if they are girls , and if they are boys , they go to armed robbery , bad things like that . so the main reason i always tell the story is just to let them know that poverty can not conquer you for the rest of your life . you can conquer poverty as well . [ ♪ native music ♪ ] [ dog barking ] [ ♪ native music ♪ ] there is a way that you can go . there is a solution to poverty . they always do things that are unethical because they say they are going through poverty . [ ♪ native music ♪ ] i 've never done anything to anyone when i was very poor , but here i am today . i 'm not as poor as i was before and for me , now , i do n't feel like i 'm poor , even though i do n't have everything i want . i do n't have a big house , i do n't have a car , but i still feel that i am rich because i am rich inside . [ speaking in native language ] [ laughter ] this is a very good friend of mine . i grew up playing with him on the street . he was never a very good player , but a very good goal keeper . [ laughter ] come try it : [ gaming device sounds ] [ winning tune ] [ quarters hitting the metal return ] i 've won . it 's my lucky day . there you go , that 's all the money . [ ♪ native hip-hop music ♪ ] soccer helped me to stay away from the option of being a prostitute . i have always had love for my football and discipline . if you are going to be doing all the wrong things to try and get something to eat , or money , then those things wo n't be in-line with your football . if you look at soccer , the things you do that are in line with football , they are also in line with your own life . [ ♪ native hip-hop music ♪ ] people love soccer , and the young kids out there , they are interested in soccer . if you talk about soccer , they all know what you 're talking about , because everyone knows about soccer . so its easy to reach out to the people with soccer . [ ♪ native hip-hop music ♪ ] grassroots soccer we have the kids who know how to prevent themselves from getting hiv and also to teach them life skills . [ ♪ native hip-hop music ♪ ] the older guys have gone through things in their lives , but would like to teach the kids so that they could not go through those things . the way we would do is with interactive games . so we do n't really say , `` yeah , we 're going to talk about hiv now . '' some people might just lose interest in it , but simply because its interactive , we do the actual activities where they just learn from them . and its not as if we are telling them what to do , like to abstain . [ ♪ native hip-hop music ♪ ] so why was it not easy to find the ball ? because you could n't see the ball . so remember when we play that game , what did you say ? teacher > yes my girl , say it . student > someone who has the ball is going to be hiv positive . so what does that tell you about hiv ? you ca n't see someone who has hiv . [ clapping ] since we work with kids we use the power of soccer , and we use soccer balls because kids love to play . if you just make them play , especially with our street leagues , the way we do the teaching for hiv and aids gives them time to play soccer . [ ♪ native hip-hop music ♪ ] those are tools for them to be better people , to stay away from things that could destroy their lives . [ ♪ native hip-hop music ♪ ] after we 've done the program , we also assess the change in their attitudes . [ ♪ native hip-hop music ♪ ] [ clapping ] if there 's a big difference where their attitudes were before they went through the program , i would be very happy about that . [ ♪ native music ♪ ] when you 've got something in your heart and you also want someone else to have that same feeling , i do n't know how to say it ... but it 's always important to just share things with other people . it 's just important . if you know you can do something to help the next person , just do it with all your heart . and not expect to get a reward . it really makes more sense to be able to have others help because , really , we can not live in isolation . honestly , we could be a unity here , but what about the others that are not a unity ? we are going to say , yes we are a unity , that is fine for us . they are not a unity , that 's their own problem . it should n't be like that . [ ♪ native music ♪ ] if people could unite . i 'm telling you , i do n't see anything stopping the world from being a better place . i do n't see anything stopping it . [ ♪ native music ♪ ] it does n't take much for soccer to get people together . if there 's a soccer match somewhere , as long as they know that match is somewhere , they will definitely go . it 's really easy for it to unite people . [ ♪ native music ♪ ] for me its really about passion because i love soccer . i love soccer . it just really ... even if i can be stressed out about something , at my training session or at my game , i forget about it . i do n't know what to say about soccer , but that 's the thing about it . i just do n't know what it is . [ ♪ native music ♪ ] nolusindiso `` titie '' plaatjie is 22 years old and lives in port elizabeth south africa . she studied human movement science at nelson mandela metropolitan university and dreams of becoming an engineer . titie is a well-known soccer star , and in 2001 , she was named captain of the provincial team . she has been playing soccer since the age of five . currently working for grassroots soccer as the port elizabeth project coordinator , titie is a key facilitator in raising hiv ? aids awareness among youth and people of her community . she believes that this is a fight for the world . www.globalonenessproject.org
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global oneness project a game for life i do n't know how i can really put this , but my football is really something that is very powerful in my life , that gives me the drive to be who i am now , and have the goals i have now . i think if it was n't for football… i ca n't really imagine myself without football .
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complete the following sentence found in a classroom in the film : “ knowledge is ________ . ''
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hunger claws at your grumbling belly . it tugs at your intestines , which begin to writhe , aching to be fed . being hungry generates a powerful , often unpleasant physical sensation that 's almost impossible to ignore . after you 've reacted by gorging on your morning pancakes , you start to experience an opposing force , fullness , but how does your body actually know when you 're full ? the sensation of fullness is set in motion as food moves from your mouth down your esophagus . once it hits your stomach , it gradually fills the space . that causes the surrounding muscular wall to stretch , expanding slowly like a balloon . a multitude of nerves wrapped intricately around the stomach wall sense the stretching . they communicate with the vagus nerve up to the brainstem and hypothalamus , the main parts of the brain that control food intake . but that 's just one input your brain uses to sense fullness . after all , if you fill your stomach with water , you wo n't feel full for long . your brain also takes into account chemical messengers in the form of hormones produced by endocrine cells throughout your digestive system . these respond to the presence of specific nutrients in your gut and bloodstream , which gradually increase as you digest your food . as the hormones seep out , they 're swept up by the blood and eventually reach the hypothalamus in the brain . over 20 gastrointestinal hormones are involved in moderating our appetites . one example is cholecystokinin , which is produced in response to food by cells in the upper small bowel . when it reached the hypothalamus , it causes a reduction in the feeling of reward you get when you eat food . when that occurs , the sense of being satiated starts to sink in and you stop eating . cholecystokinin also slows down the movement of food from the stomach into the intestines . that makes your stomach stretch more over a period of time , allowing your body to register that you 're filling up . this seems to be why when you eat slowly , you actually feel fuller compared to when you consume your food at lightning speed . when you eat quickly , your body does n't have time to recognize the state it 's in . once nutrients and gastrointestinal hormones are present in the blood , they trigger the pancreas to release insulin . insulin stimulates the body 's fat cells to make another hormone called leptin . leptin reacts with receptors on neuron populations in the hypothalamus . the hypothalamus has two sets of neurons important for our feeling of hunger . one set produces the sensation of hunger by making and releasing certain proteins . the other set inhibits hunger through its own set of compounds . leptin inhibits the hypothalamus neurons that drive food intake and stimulates the neurons that suppress it . by this point , your body has reached peak fullness . through the constant exchange of information between hormones , the vagus nerve , the brainstem , and the different portions of hypothalamus , your brain gets the signal that you 've eaten enough . researchers have discovered that some foods produce more long-lasting fullness than others . for instance , boiled potatoes are ranked as some of the most hunger-satisfying foods , while croissants are particularly unsatisfying . in general , foods with more protein , fiber , and water tend to keep hunger at bay for longer . but feeling full wo n't last forever . after a few hours , your gut and brain begin their conversation again . your empty stomach produces other hormones , such as ghrelin , that increase the activity of the hunger-causing nerve cells in the hypothalamus . eventually , the growling beast of hunger is reawakened . luckily , there 's a dependable antidote for that .
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when you eat quickly , your body does n't have time to recognize the state it 's in . once nutrients and gastrointestinal hormones are present in the blood , they trigger the pancreas to release insulin . insulin stimulates the body 's fat cells to make another hormone called leptin .
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what hormone is released from your pancreas when nutrients and gastrointestinal hormones are present in the blood ?
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imagine being a fossil : touring the world 's great museums , inspiring awe in onlookers of all ages , posing for hordes of fawning photographers . sound like something you 'd like ? well , good luck ! at least 99.9 % of creatures that have ever lived are n't preserved in the fossil record . but forget about them , everyone else will , and listen up ! if you want your corpse in the exclusive 0.01 % club , the hall of preserved fossil fame , it will not be easy . you better work ! step one : die . it 's a cold , hard fact of fossilization . everything paleontologists find was once alive and , at some point , died . we 'll skip the details and assume you had a long , fulfilling life so we can get to what is really important -- how you die . there are many ways to become a fossil , so let 's highlight your top death options . you could get yourself trapped in tree sap , which , when hardens , turns into amber and can survive intact for millions of years . but unless you find a really big tree to sit under , amber preservation will likely remain the domain of insects and other very small animals . generally , the right place to be if you want to end up a fossil is wherever sediment is actively being deposited , like a lake or an ocean floor . a mountaintop or prairie ? not good ! you need to get buried , the faster the better , because the longer you hang around on the surface , the more likely you 'll get eaten , scavenged , or otherwise destroyed before ever having a chance to get preserved . if you can get buried someplace with little to no oxygen , like a bog or a deep lake bottom , even better . that lack of oxygen will slow down your decay and give you more time to fossilize . so , let 's say you 're lucky enough to die and get buried in a shallow sea under muddy , sandy sediments . what 's your next move ? one option is a process called permineralization . while all your soft parts decay away , your bones get saturated with mineral-rich waters . bit by bit , microscopic crystals precipitate out of these waters to fill in the empty spaces and pores in your bones . otherwise , you 'd better hope the sediments around you harden while your bones decay away and another sediment or mineral fills in the spaces your bones leave behind , creating a perfect cast of your skeleton . over time , the sediments around your fossil will lithify or turn into rock . but you 're not in the clear yet ! many things could happen to those sedimentary rocks that might destroy your chances of getting discovered . they could get uplifted into a mountain range and eroded away or carried along in an oceanic plate and subducted back into the earth 's mantle , melting your fossil into hot mush . fingers crossed your rock surroundings will get gently lifted up by plate tectonics , sea levels will change , and you 'll end up under dry land close to the surface , but not so close that erosion from wind and rain wipes you away before someone can come find you . the last step in this long process , an intrepid paleontologist has to come find you . maybe she 's a research scientist scouting for fossils your age and type or just an amateur collector hoping for a fortuitous find . she whacks away at layers of rock above you or spots your fossil exposed in a creek bank after a flood . and there you are , a magnificent scientific discovery , millions of years in the making ! she and her colleagues gently extract you from the surrounding sediment , measure and photograph all the bits and pieces they find , and begin the complex task of reconstructing how and when you lived based on the evidence they find in your bones . paleontologists will be some of your biggest fans along with all those admiring crowds at the museum . you made it ! you spent years underground in obscurity , shedding blood , sweat , tears , and your internal organs . you worked yourself to the bone until your bones disintegrated and were replaced by minerals and sediments . but it was all worth it because you 're a famous fossil ! now , you better hold that pose !
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what 's your next move ? one option is a process called permineralization . while all your soft parts decay away , your bones get saturated with mineral-rich waters .
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which of the following process are not likely to ruin your chances of becoming a fossil ?
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to human eyes , the world at night is a formless canvas of grey . many nocturnal animals , on the other hand , experience a rich and varied world bursting with details , shapes , and colors . what is it , then , that separates moths from men ? moths and many other nocturnal animals see at night because their eyes are adapted to compensate for the lack of light . all eyes , whether nocturnal or not , depend on photoreceptors in the retina to detect light particles , known as photons . photoreceptors then report information about these photons to other cells in the retina and brain . the brain sifts through that information and uses it to build up an image of the environment the eye perceives . the brighter the light is , the more photons hit the eye . on a sunny day , upwards of 100 million times more photons are available to the eye than on a cloudy , moonless night . photons are n't just less numerous in darkness , but they also hit the eye in a less reliable way . this means the information that photoreceptors collect will vary over time , as will the quality of the image . in darkness , trying to detect the sparse scattering of randomly arriving photons is too difficult for the eyes of most daytime animals . but for night creatures , it 's just a matter of adaptation . one of these adaptations is size . take the tarsier , whose eyeballs are each as big as its brain , giving it the biggest eyes compared to head size of all mammals . if humans had the same brain to eye ratio , our eyes would be the size of grapefruits . the tarsier 's enlarged orbs have n't evolved to make it cuter , however , but to gather as much light as possible . bigger eyes can have larger openings , called pupils , and larger lenses , allowing for more light to be focused on the receptors . while tarsiers scan the nocturnal scene with their enormous peepers , cats use gleaming eyes to do the same . cats ' eyes get their shine from a structure called the tapetum lucidum that sits behind the photoreceptors . this structure is made from layers of mirror-like cells containing crystals that send incoming light bouncing back towards the photoreceptors and out of the eye . this results in an eerie glow , and it also gives the photoreceptors a second chance to detect photons . in fact , this system has inspired the artificial cats ' eyes we use on our roads . toads , on the other hand , have adapted to take it slow . they can form an image even when just a single photon hits each photoreceptor per second . they accomplish this with photoreceptors that are more than 25 times slower than human ones . this means toads can collect photons for up to four seconds , allowing them to gather many more than our eyes do at each visual time interval . the downside is that this causes toads to react very slowly because they 're only receiving an updated image every four seconds . fortunately , they 're accustomed to targeting sluggish prey . meanwhile , the night is also buzzing with insects , such as hawk moths , which can see their favorite flowers in color , even on a starlit night . they achieve this by a surprising move - getting rid of details in their visual perception . information from neighboring photoreceptors is grouped in their brains , so the photon catch of each group is higher compared to individual receptors . however , grouping photoreceptors loses details in the image , as fine details require a fine grid of photoreceptors , each detecting photons from one small point in space . the trick is to balance the need for photons with the loss of detail to still find their flowers . whether eyes are slow , enormous , shiny , or coarse , it 's the combination of these biological adaptations that gives nocturnal animals their unique visual powers . imagine what it might be like to witness through their eyes the world that wakes up when the sun goes down .
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they can form an image even when just a single photon hits each photoreceptor per second . they accomplish this with photoreceptors that are more than 25 times slower than human ones . this means toads can collect photons for up to four seconds , allowing them to gather many more than our eyes do at each visual time interval .
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why do toad photoreceptors react so much slower than ours ?
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hey , vsauce . michael here . and what if every single person on earth jumped at the exact same time ? could it cause an earthquake or would we not even be able to tell ? well , first things first , let 's talk about the earth 's rotation . the earth spins , that 's why we have night and day , and it spins quickly . at the equator , the earth is spinning at more than 1,000 mph . now , a spinning ice skater can speed up by moving mass closer to the center and the earth is no different . in fact , if you get down on the ground right now and move your mass closer to earth 's center , technically , you will speed up earth 's rotation , making this day shorter . now , the change that you would make to the earth 's rotation is way smaller than we could even measure , but it is calculable , and the impact can be quite impressive when you talk about redistributing more mass than just one person . for instance , last year , the earthquake in japan redistributed so much of earth 's mass towards the center , that every day since then has been 1.8 microseconds shorter . but that was a giant geological event . what can us humans do to the earth all on our own ? i mean , there are more than 7 billion of us now . what if we all got together in one place and jumped ? well , what would that even look like ? interestingly , if you took the entire human population of earth and had them all live in one place with the same density that people live in in new york city , you could fit everyone - all of us - into the state of texas . but that 's living , not standing around in a crowd , which is how we would probably want to do the jump . if every single person alive right now on earth stood shoulder to shoulder , you could fit all of us into the city of los angeles . it would be an incredible sight to behold - a mere 500 square miles containing every single person on earth . ok , so , then we jump . what happens ? unfortunately , not much . i mean , we 're all awesome people here on earth , but our collective mass compared to the mass of the entire earth ? it 's like nothing . in fact , dot physics calculated that if all of us were to get together in one location and all jump 30 cm into the air at the exact same time , we would push earth away from us a tiny amount . earth would only move away from us about 1/100th of the width of a single hydrogen atom . and here 's another thing . because we 're all jumping and then going back to where we started , earth is just going to move back to where it started . so , our big jump wo n't be able to change earth 's position in space , but , c'mon , 7 billion people all jumping together ? that 's got ta be able to cause some sort of seismic activity , right ? so let 's say you have a lot of people all together in one place and you have them all jump on : 1-2-3 ! did you feel that ? well , the bbc did this with 50,000 people and discovered that a kilometer and a half away , it only registered a .6 on the richter scale . you would need 7 million times more people than even live on earth right now to jump at once to recreate the earthquake that recently happened in japan . so , even though we 're all awesome , compared to the size of the earth , we 're not much . but do n't get too discouraged . our collective jump would contain a lot of energy . the straight dope calculated that even if only the people who lived in china got together and jumped , their jump would be the equivalent of 500 tons of tnt . of course , 500 tons of tnt does n't do much to an earth that weighs 6 sextillion 588 quintillion tons . to make yourself feel more powerful , pick a card . i 've got 10 of them here , let 's say , hmmm , you choose this one . boom , congratulations , we have just decimated this deck of cards . why ? well because , technically , decimate does not mean `` obliterate completely . '' deci=10 . it means to take away 1/10th of something . so , the next time you take a quiz and do n't do so well on it , you only get 10 % . well , sure , that 's an `` f '' , but by getting 10 % of them right , you decimated that quiz . and since we 've been talking about crowds , let 's talk about youtube crowds . youtube audiences , that view count that you see at the bottom of every video , and get some perspective on it . we 'll being with dunbar 's number . it 's an estimation of the maximum number of people we can have stable , social relationships with at a given moment and it 's based on the size of our neo-cortex . these are n't just acquaintances , these are people you have social contact with - a network where you know how everyone relates to everyone else . and the number is usually given to be somewhere between 100-230 , which means that when a youtube video receives more than 230 views from different people , more people have seen that video than you could ever realistically hope to know well , at a given moment . if a video has more than 100,000 views from different people , more people have seen that video than you will ever meet in your life . and by meet , i mean shakes hands with , learn their name , talk with them for a bit . i mean , think of it this way . you and me , we 're only statistically expected to live around 28,470 days . so , even if you were to meet someone , 2-3 people every day of your life , including when you were a baby , you still would n't meet as many people as have seen that youtube video with 100,000 views . but keep this in mind . even though you , or even a large group of us , ca n't do much to change earth 's location or rotation , we can affect it a little bit . newton 's third law guarantees this . if you weigh 150 pounds , the earth is pulling you down with a force of 150 pounds . but you are also pulling up on the earth with a force of 150 pounds . if you fall 3 meters , the earth has pulled you down 3 meters . but you have also exerted a equal and opposite force on the earth . of course , it 's a lot bigger . so , if you fall 3 meters , you pull the earth up about a billionth of the width of a proton , which ai n't bad . so the next time you move your body , the next time you jump , felicia , think about this . you just affected the earth as much as it affected you . you 've got that kind of power . speaking of power , you all should go check out `` geek & amp ; amp ; sundry '' , felicia 's new channel . it 's one of my new favorite things . and as always , thanks for watching .
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youtube audiences , that view count that you see at the bottom of every video , and get some perspective on it . we 'll being with dunbar 's number . it 's an estimation of the maximum number of people we can have stable , social relationships with at a given moment and it 's based on the size of our neo-cortex .
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what does dunbar 's number ( 100-230 ) attempt to represent ?
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translator : elena montrasio reviewer : ted translators admin [ his holiness pope francis filmed in vatican city first shown at ted2017 ] good evening – or , good morning , i am not sure what time it is there . regardless of the hour , i am thrilled to be participating in your conference . i very much like its title – `` the future you '' – because , while looking at tomorrow , it invites us to open a dialogue today , to look at the future through a `` you . '' `` the future you : '' the future is made of yous , it is made of encounters , because life flows through our relations with others . quite a few years of life have strengthened my conviction that each and everyone 's existence is deeply tied to that of others : life is not time merely passing by , life is about interactions . as i meet , or lend an ear to those who are sick , to the migrants who face terrible hardships in search of a brighter future , to prison inmates who carry a hell of pain inside their hearts , and to those , many of them young , who can not find a job , i often find myself wondering : `` why them and not me ? '' i , myself , was born in a family of migrants ; my father , my grandparents , like many other italians , left for argentina and met the fate of those who are left with nothing . i could have very well ended up among today 's `` discarded '' people . and that 's why i always ask myself , deep in my heart : `` why them and not me ? '' first and foremost , i would love it if this meeting could help to remind us that we all need each other , none of us is an island , an autonomous and independent `` i , '' separated from the other , and we can only build the future by standing together , including everyone . we don ’ t think about it often , but everything is connected , and we need to restore our connections to a healthy state . even the harsh judgment i hold in my heart against my brother or my sister , the open wound that was never cured , the offense that was never forgiven , the rancor that is only going to hurt me , are all instances of a fight that i carry within me , a flare deep in my heart that needs to be extinguished before it goes up in flames , leaving only ashes behind . many of us , nowadays , seem to believe that a happy future is something impossible to achieve . while such concerns must be taken very seriously , they are not invincible . they can be overcome when we do n't lock our door to the outside world . happiness can only be discovered as a gift of harmony between the whole and each single component . even science – and you know it better than i do – points to an understanding of reality as a place where every element connects and interacts with everything else . and this brings me to my second message . how wonderful would it be if the growth of scientific and technological innovation would come along with more equality and social inclusion . how wonderful would it be , while we discover faraway planets , to rediscover the needs of the brothers and sisters orbiting around us . how wonderful would it be if solidarity , this beautiful and , at times , inconvenient word , were not simply reduced to social work , and became , instead , the default attitude in political , economic and scientific choices , as well as in the relationships among individuals , peoples and countries . only by educating people to a true solidarity will we be able to overcome the `` culture of waste , '' which does n't concern only food and goods but , first and foremost , the people who are cast aside by our techno-economic systems which , without even realizing it , are now putting products at their core , instead of people . solidarity is a term that many wish to erase from the dictionary . solidarity , however , is not an automatic mechanism . it can not be programmed or controlled . it is a free response born from the heart of each and everyone . yes , a free response ! when one realizes that life , even in the middle of so many contradictions , is a gift , that love is the source and the meaning of life , how can they withhold their urge to do good to another fellow being ? in order to do good , we need memory , we need courage and we need creativity . and i know that ted gathers many creative minds . yes , love does require a creative , concrete and ingenious attitude . good intentions and conventional formulas , so often used to appease our conscience , are not enough . let us help each other , all together , to remember that the other is not a statistic or a number . the other has a face . the `` you '' is always a real presence , a person to take care of . there is a parable jesus told to help us understand the difference between those who 'd rather not be bothered and those who take care of the other . i am sure you have heard it before . it is the parable of the good samaritan . when jesus was asked : `` who is my neighbor ? '' - namely , `` who should i take care of ? '' - he told this story , the story of a man who had been assaulted , robbed , beaten and abandoned along a dirt road . upon seeing him , a priest and a levite , two very influential people of the time , walked past him without stopping to help . after a while , a samaritan , a very much despised ethnicity at the time , walked by . seeing the injured man lying on the ground , he did not ignore him as if he were n't even there . instead , he felt compassion for this man , which compelled him to act in a very concrete manner . he poured oil and wine on the wounds of the helpless man , brought him to a hostel and paid out of his pocket for him to be assisted . the story of the good samaritan is the story of today ’ s humanity . people 's paths are riddled with suffering , as everything is centered around money , and things , instead of people . and often there is this habit , by people who call themselves `` respectable , '' of not taking care of the others , thus leaving behind thousands of human beings , or entire populations , on the side of the road . fortunately , there are also those who are creating a new world by taking care of the other , even out of their own pockets . mother teresa actually said : `` one can not love , unless it is at their own expense . '' we have so much to do , and we must do it together . but how can we do that with all the evil we breathe every day ? thank god , no system can nullify our desire to open up to the good , to compassion and to our capacity to react against evil , all of which stem from deep within our hearts . now you might tell me , `` sure , these are beautiful words , but i am not the good samaritan , nor mother teresa of calcutta . '' on the contrary : we are precious , each and every one of us . each and every one of us is irreplaceable in the eyes of god . through the darkness of today 's conflicts , each and every one of us can become a bright candle , a reminder that light will overcome darkness , and never the other way around . to christians , the future does have a name , and its name is hope . feeling hopeful does not mean to be optimistically naïve and ignore the tragedy humanity is facing . hope is the virtue of a heart that does n't lock itself into darkness , that does n't dwell on the past , does not simply get by in the present , but is able to see a tomorrow . hope is the door that opens onto the future . hope is a humble , hidden seed of life that , with time , will develop into a large tree . it is like some invisible yeast that allows the whole dough to grow , that brings flavor to all aspects of life . and it can do so much , because a tiny flicker of light that feeds on hope is enough to shatter the shield of darkness . a single individual is enough for hope to exist , and that individual can be you . and then there will be another `` you , '' and another `` you , '' and it turns into an `` us . '' and so , does hope begin when we have an `` us ? '' no . hope began with one `` you . '' when there is an `` us , '' there begins a revolution . the third message i would like to share today is , indeed , about revolution : the revolution of tenderness . and what is tenderness ? it is the love that comes close and becomes real . it is a movement that starts from our heart and reaches the eyes , the ears and the hands . tenderness means to use our eyes to see the other , our ears to hear the other , to listen to the children , the poor , those who are afraid of the future . to listen also to the silent cry of our common home , of our sick and polluted earth . tenderness means to use our hands and our heart to comfort the other , to take care of those in need . tenderness is the language of the young children , of those who need the other . a child ’ s love for mom and dad grows through their touch , their gaze , their voice , their tenderness . i like when i hear parents talk to their babies , adapting to the little child , sharing the same level of communication . this is tenderness : being on the same level as the other . god himself descended into jesus to be on our level . this is the same path the good samaritan took . this is the path that jesus himself took . he lowered himself , he lived his entire human existence practicing the real , concrete language of love . yes , tenderness is the path of choice for the strongest , most courageous men and women . tenderness is not weakness ; it is fortitude . it is the path of solidarity , the path of humility . please , allow me to say it loud and clear : the more powerful you are , the more your actions will have an impact on people , the more responsible you are to act humbly . if you don ’ t , your power will ruin you , and you will ruin the other . there is a saying in argentina : `` power is like drinking gin on an empty stomach . '' you feel dizzy , you get drunk , you lose your balance , and you will end up hurting yourself and those around you , if you don ’ t connect your power with humility and tenderness . through humility and concrete love , on the other hand , power – the highest , the strongest one – becomes a service , a force for good . the future of humankind is n't exclusively in the hands of politicians , of great leaders , of big companies . yes , they do hold an enormous responsibility . but the future is , most of all , in the hands of those people who recognize the other as a `` you '' and themselves as part of an `` us . '' we all need each other . and so , please , think of me as well with tenderness , so that i can fulfill the task i have been given for the good of the other , of each and every one , of all of you , of all of us . thank you .
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i am sure you have heard it before . it is the parable of the good samaritan . when jesus was asked : `` who is my neighbor ? ''
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briefly describe the parable of the good samaritan .
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ani stands before a large golden scale where the jackal-headed god anubis is weighing his heart against a pure ostrich feather . ani was a real person , a scribe from the egyptian city of thebes who lived in the 13th century bce . and depicted here is a scene from his book of the dead , a 78-foot papyrus scroll designed to help him attain immortality . such funerary texts were originally written only for pharaohs , but with time , the egyptians came to believe regular people could also reach the afterlife if they succeeded in the passage . ani 's epic journey begins with his death . his body is mummified by a team of priests who remove every organ except the heart , the seat of emotion , memory , and intelligence . it 's then stuffed with a salt called natron and wrapped in resin-soaked linen . in addition , the wrappings are woven with charms for protection and topped with a heart scarab amulet that will prove important later on . the goal of the two-month process is to preserve ani 's body as an ideal form with which his spirit can eventually reunite . but first , that spirit must pass through the duat , or underworld . this is a realm of vast caverns , lakes of fire , and magical gates , all guarded by fearsome beasts - snakes , crocodiles , and half-human monstrosities with names like `` he who dances in blood . '' to make things worse , apep , the serpent god of destruction , lurks in the shadows waiting to swallow ani 's soul . fortunately , ani is prepared with the magic contained within his book of the dead . like other egyptians who could afford it , ani customized his scroll to include the particular spells , prayers , and codes he thought his spirit might need . equipped with this arsenal , our hero traverses the obstacles , repels the monsters ' acts , and stealthily avoids apep to reach the hall of ma'at , goddess of truth and justice . here , ani faces his final challenge . he is judged by 42 assessor gods who must be convinced that he has lived a righteous life . ani approaches each one , addressing them by name , and declaring a sin he has not committed . among these negative confessions , or declarations of innocence , he proclaims that he has not made anyone cry , is not an eavesdropper , and has not polluted the water . but did ani really live such a perfect life ? not quite , but that 's where the heart scarab amulet comes in . it 's inscribed with the words , `` do not stand as a witness against me , '' precisely so ani 's heart does n't betray him by recalling the time he listened to his neighbors fight or washed his feet in the nile . now , it 's ani 's moment of truth , the weighing of the heart . if his heart is heavier than the feather , weighed down by ani 's wrongdoings , it 'll be devoured by the monstrous ammit , part crocodile , part leopard , part hippopotamus , and ani will cease to exist forever . but ani is in luck . his heart is judged pure . ra , the sun god , takes him to osiris , god of the underworld , who gives him final approval to enter the afterlife . in the endless and lush field of reeds , ani meets his deceased parents . here , there is no sadness , pain , or anger , but there is work to be done . like everyone else , ani must cultivate a plot of land , which he does with the help of a shabti doll that had been placed in his tomb . today , the papyrus of ani resides in the british museum , where it has been since 1888 . only ani , if anyone , knows what really happened after his death . but thanks to his book of the dead , we can imagine him happily tending his crops for all eternity .
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ani 's epic journey begins with his death . his body is mummified by a team of priests who remove every organ except the heart , the seat of emotion , memory , and intelligence . it 's then stuffed with a salt called natron and wrapped in resin-soaked linen .
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during the mummification process , every organ was removed except the :
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this is a map of yellowstone national park for the most part the park is in wyoming but it extends a bit into montana and idaho this little 50 square miles section in idaho is what concerns us it 's called the zone of death because of a loophole that exists in the constitution of the united states if someone were to exploit that loophole they might be able to get away with murder yellowstone was established in 1872 before wyoming idaho and montana join the union it 's federal land and always has been but federal land across the u.s. is split up and divided into its corresponding state district courts except for yellowstone and this is where the loophole begins law professor brian c. kalt points out in his 2005 paper the perfect crime that yellowstone national park was assigned fully to wyoming 's district court even though small portions fall into montana and idaho unlike every other district the district of wyoming includes land in other state so kalt asks the question what happens if you 're caught for a crime you committed in that 50 square mile idea who region of the park the first thing law enforcement would do is bring you to cheyenne the hub of the district court of wyoming because the crime technically happened within wyoming 's jurisdiction but article 3 section 2 of the united states constitution says that the trial should happen in the state where you committed the crime if you 're a savvy murderer you invoke your right to a trial in idaho so they bring you back to idaho no big deal in the sixth amendment they said that they would require local juries and the language they use is that the jury has to be from the state and district where the crime was committed this is called the vicinage clause that leaves you with a sort of venn diagram you have the right to demand jury from that middle area where the state in which you committed the crime that 's idaho overlaps with the judicial jurisdiction where you committed the crime the wyoming district that has jurisdiction over yellowstone national park and here 's the problem nobody lives there there 's there 's no way for them to give you a trial and so i argue they should have to let you go this could also happen in the montana portion of the park except a few dozen people do live there so a jury could theoretically be called kalt has proposed numerous solutions to congress to fix the loophole but they have yet to act all they have to do is redraw the district line so that the district of wyoming is wyoming the district of idaho is in idaho and the district of montana in montana and if they do that it all goes away so if you 're planning a gathering of your adversaries exes and debtors maybe try yosemite
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this is a map of yellowstone national park for the most part the park is in wyoming but it extends a bit into montana and idaho this little 50 square miles section in idaho is what concerns us it 's called the zone of death because of a loophole that exists in the constitution of the united states if someone were to exploit that loophole they might be able to get away with murder yellowstone was established in 1872 before wyoming idaho and montana join the union it 's federal land and always has been but federal land across the u.s. is split up and divided into its corresponding state district courts except for yellowstone and this is where the loophole begins law professor brian c. kalt points out in his 2005 paper the perfect crime that yellowstone national park was assigned fully to wyoming 's district court even though small portions fall into montana and idaho unlike every other district the district of wyoming includes land in other state so kalt asks the question what happens if you 're caught for a crime you committed in that 50 square mile idea who region of the park the first thing law enforcement would do is bring you to cheyenne the hub of the district court of wyoming because the crime technically happened within wyoming 's jurisdiction but article 3 section 2 of the united states constitution says that the trial should happen in the state where you committed the crime if you 're a savvy murderer you invoke your right to a trial in idaho so they bring you back to idaho no big deal in the sixth amendment they said that they would require local juries and the language they use is that the jury has to be from the state and district where the crime was committed this is called the vicinage clause that leaves you with a sort of venn diagram you have the right to demand jury from that middle area where the state in which you committed the crime that 's idaho overlaps with the judicial jurisdiction where you committed the crime the wyoming district that has jurisdiction over yellowstone national park and here 's the problem nobody lives there there 's there 's no way for them to give you a trial and so i argue they should have to let you go this could also happen in the montana portion of the park except a few dozen people do live there so a jury could theoretically be called kalt has proposed numerous solutions to congress to fix the loophole but they have yet to act all they have to do is redraw the district line so that the district of wyoming is wyoming the district of idaho is in idaho and the district of montana in montana and if they do that it all goes away so if you 're planning a gathering of your adversaries exes and debtors maybe try yosemite
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how could this loophole be fixed ?
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why can ’ t i just get on a plane and go from , like , montana to london , in a couple hours ? i just want to experience the thrill of zooming through the sky faster than the speed of sound ? well , if you flew on a concorde jet back before they were grounded -- or you happen to be a fighter pilot -- then you ’ ve probably experienced faster-than-sound travel . and , some companies are looking to make supersonic flight a reality again , with new commercial planes that travel faster than the speed of sound . and someday , you might be able to fly over the atlantic ocean in an hour -- or even less . problem is , most people don ’ t want to fly on a plane that feels like an out-of-control rocket . and there ’ s also the problem of faster-than-sound planes becoming ridiculously hot and unbearably loud . so engineers have some developing to do . on the morning of december 17th , 1903 , orville wright became the first human to successfully pilot an airplane -- a heavier-than-air vehicle that was controlled , powered , and sustained . his flight lasted 12 seconds , and crossed 120 feet of a north carolinian beach -- with an average speed of almost 11 kilometers an hour . by the end of the day , his brother wilbur flew the same airplane for almost a whole minute , with an average speed of almost 16 kilometers an hour . less than a century later , in the 1970s , commercial planes went supersonic -- faster than the speed of sound . a few dozen supersonic planes were in regular service , available in two models , the concorde and the soviet tupolev . but the tupolev only made 55 passenger flights , from 1977 to 1978 . and after a concorde crashed in 2000 , people started to fly on them less . eventually , they just weren ’ t financially worth it anymore , and the planes were retired in 2003 . 13 years later , there still aren ’ t any new commercial faster-than-sound planes . but soon , there might be ! there are just a couple of improvements companies are trying to make first . the main challenge comes from getting past what ’ s known as mach 1 . see , sound usually travels around 1230 kilometers per hour , but that ’ s not a constant number -- it depends on things like the temperature and humidity of the air . so , when it comes to planes , it ’ s easier to talk about speed in mach numbers , which take into account the speed of sound in the particular place where the plane is flying.. mach 1 is just the speed of sound . anything slower than that is called subsonic , and anything faster is called supersonic . but switching from subsonic to supersonic isn ’ t easy , because the plane has to overcome the infamous sound barrier . and that can be a problem , because the sound barrier is sometimes strong enough to tear away at planes , and even send them crashing to the ground . the sound barrier exists because of the way sound waves travel : by compressing and stretching the air they travel through . the compressed air ends up at a higher pressure , and the stretched air has lower pressure . as a plane moves , it produces sound waves that shift the air back and forth , creating areas of lower and higher pressure . but as the plane gets faster , it starts to catch up with those waves . new sound waves start to form on top of the old sound waves , causing huge swings between higher and lower pressure air . those differences in pressure can rattle and shake planes like toys , and there ’ s a real danger of tearing them to pieces . low pressure areas can also lead to drops in temperature , condensing any moisture in the air and forming a visible cloud , sometimes known as a vapor cone . the first plane that could get past the sound barrier was the bell x-1 , built in 1947 . it was designed to absorb 18 times the force of gravity , and modeled after a machine gun bullet . it didn ’ t actually lift off from the ground on the zone , though -- it was dropped from a larger mothership plane , known as the b-29 , so it got a bit of a head start . by the mid-1970s , supersonic planes were ready for commercial use -- with the uk and france designing the concorde , and the soviet union designing the tupolev . the concorde flew passengers from london to new york in about three and a half hours -- about half the time it would take in a plain old subsonic commercial plane . but they only flew that one route , and there ’ s a reason they spent as much time over the water as possible : the painfully disruptive sonic boom . like the sound barrier , sonic booms come from a build-up of compressed sound waves , known as a shock wave . the shock wave heads away from the plane , which you hear as a very loud boom -- so powerful that they ’ re sometimes mistaken for earthquakes . and those sonic booms don ’ t just happen once , like when a plane breaks the sound barrier . they continue throughout the entire supersonic flight . that ’ s because the sound waves keep bunching up behind the plane , then expanding outwards , creating a cone shape known as the mach cone . so wherever the plane flies over land , people hear that incredibly loud boom . so that ’ s why the concorde ’ s supersonic commercial flights only really happened between western europe and eastern north america . if they flew over land , odds are people would not have appreciated the booms . and even though you can ’ t fly on a concorde anymore , you might still be able to fly on a supersonic plane someday . nasa , for example , is looking into how to dampen the effects of the sonic boom . one way to do that might be by moving one , or even two engines above the wings , which would direct shockwaves upwards . so the sonic booms would happen in the sky , rather than on the ground . then there ’ s the concorde 2 , which airbus is working on . the concorde 2 would first fly directly upward , to an altitude of about 30 kilometers . then , the plane would rotate its tail fin in a way that would redirect the shock waves to be horizontal , so you wouldn ’ t feel them as much on the ground . the concorde 2 would be able to accelerate up to mach 4.5 -- and at those speeds , it could take passengers from london to new york in an hour . but maybe that ’ s not enough , what if you want to go faster ? the concorde 2 would be very close to going beyond supersonic , and into an even faster category , known as hypersonic . when people talk about hypersonic speeds , they ’ re generally talking about mach 5 or higher -- more than five times the speed of sound . those speeds get their own category , because that ’ s when the temperature of the plane becomes a bigger issue . the plane is flying through the air so quickly that friction with particles in the air is a real problem , because it makes a lot of heat . at hypersonic speeds , planes need to be able to withstand temperatures over 1000 degrees celsius… but almost all of the more typical metals would melt , or at least become very weak , at temperatures below that . the other challenge is the engine , because a regular jet engine wouldn ’ t work . standard , subsonic planes use large rotating blades to compress incoming air , inject fuel , and then let it burn . propelling them forward . at supersonic speeds , it becomes even easier , because the high speeds already compress the air . in that case , the engine doesn ’ t even need the blades -- that ’ s what ’ s known as a ramjet engine . ram , because the air is just rammed into the engine . at hypersonic speeds , though , this plan doesn ’ t work as well . sure , the air is compressed , but it ’ s moving so fast that there ’ s not enough time for it to combust and actually help move the plane . so hypersonic planes need their own fuel and their own oxygen -- which is what nasa used in the x-15 , the first plane to reach hypersonic speeds . it used a titanium skin to protect itself from the extreme temperatures , and was able to fly at mach 6.72 . it also flew high enough that some of the x-15 test flights are considered space flights . but the x-15 is not the kind of plane that could be used commercially . for one thing , it burned through fuel so fast that it would run out in less than two minutes . also , pilots sometimes experienced 8 times the force of earth ’ s gravity , and most people wouldn ’ t consider that a comfortable business trip . so , until engines became more efficient and practical , commercial hypersonic planes are a long way from reality . and the scramjet might be the answer . scramjet engines work kind of like ramjets do , but they ’ re designed to handle the faster-moving air . in testing , nasa ’ s found that they could work at speeds up to mach 15 , at least in theory . there ’ s one big drawback , though : scramjet engines only work at hypersonic speeds . the x-43a , for example , an unmanned test plane that uses a scramjet , has to be accelerated above mach 5 before it can fly on its own . it ’ s strapped to a booster rocket , which is then loaded onto a subsonic plane . alright , stay with me ... the plane flies up to about 6 kilometers above the ground , then releases the x-43a , along with the rocket , which gets to about 30 kilometers up and to speeds of mach 5 . then the x-43a can start its flight . so , it might be a while before hypersonic planes are a practical way to get across the atlantic . but a future where a trip to the other side of the world involves flying faster than the speed of sound , without painful sonic booms for the people on the ground ? that might not be so far off . thanks for watching this episode of scishow , which was brought to you by our patrons on patreon . thank you patrons on patreon . if you wan na become one of those people , you can go to patreon.com/scishow . and don ’ t forget to go to youtube.com/scishow and subscribe !
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if they flew over land , odds are people would not have appreciated the booms . and even though you can ’ t fly on a concorde anymore , you might still be able to fly on a supersonic plane someday . nasa , for example , is looking into how to dampen the effects of the sonic boom .
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why did the concorde jet fly mostly over the ocean ?
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[ music ] science is coming . [ music ] the game of thrones universe is one of the most brilliantly complex and utterly frustrating fictional universes ever created . but it is a fictional universe , and the only rule of a fictional universe is that it is self-consistent . it does n't have to agree with our science , or logic , or even our commonly agreed-upon moral code that says killing people is not a good thing . there is only one god in that universe , and his name is gurm . but despite that , many things in game of thrones can be linked to the real , actual world , drawing inspiration as if through the thirsty roots of a weirwood tree . many of these connections are interpreted by fans , but some have been verified by the bearded one himself . there are the many competing religious philosophies , the many , many , many similarities to real-life historical characters or the fact that they look like us ? but we are not going to be talking about those ... here 's where i would give you a spoilers warning , but . . . come on . you clicked on this . spoilers are coming . why are the seasons so crazy ? in the game of thrones universe winters and summers are known to last years at a time and apparently show up when they damn well please . we know that the summer/winter cycle normally averages around 5 or 6 years apiece , and as the story begins the most recent summer has stretched to nearly ten years . on earth , seasons are caused by our axial tilt leaning one side of earth toward or away from the sun during our annual trip around it , but george 's world is n't so predictable . the maesters of the citadel are the geeks of westeros , who are supposed to calculate when the next polar doom will arrive . westeros is n't an industrial society , but the architecture , metallurgy , and medicine we see in the known world suggests that these guys are a fairly scientific bunch . many theories have attempted to explain the reason for these seasons , but most of them collapse faster than a greyjoy 's loyalty . we know that the westeros-ian world has a moon , and that it used to have two . maybe their moon is n't as large as ours so the planet 's axis , unstabilized by lunar gravity , wobbles like a broken top . but , according to astronomers , moons do n't stabilize planets , rather a moonless planet should spin more evenly than one with a moon . then what if its orbit , instead of a nearly circular ellipse , like ours , was extremely elongated ? well that does n't work either . while it could cause extreme seasons , they 'd still show up on a regular schedule . even complex combinations of orbital stretches and wobbles , like earth 's milankovitch cycles , could be predicted by any society that knows basic algebra . well , then maybe it 's tugged on by the gravity of a neighboring planet , or its sun has a variable output . george r.r . martin did write his first novel about a planet falling away from its parent star . it 's most likely that the game of thrones planet . . . it needs a name . planet hodor ! lives in a very strange solar system , around a pair of stars . last april , a group of graduate students from johns hopkins university published a paper showing that if the world of game of thrones was subject to the complex dynamics of three celestial bodies orbiting each other , predicting a planet 's seasons would be impossible . this has interesting implications for tatooine . . ? of course , it could also be due to magic , which is cheating . and what about that world anyway ? at the amazing planetary science blog generation anthropocene , miles traer and mike osborne have constructed a detailed geologic history of westeros stretching back more than 500 million years into the fictional past . they determined that , since the north is cold enough to maintain a wall of ice , which we 'll come back to , year-round , it must be near this planet 's arctic circle , and since the south is warm enough to be covered by deserts , which primarily exist near earth 's 30th parallel that planet hodor has a radius of 4,297 miles or about 10 % wider than earth . we know that the first men crossed into westeros on a land bridge near dorne , and like africa and south america , the coastlines of westeros and essos seem to fit like puzzle pieces . they were probably unzipped beginning 25 million years ago by a spreading rift , like the one in the middle of our atlantic ocean . and 40 million years ago , westeros was likely covered by a huge ice sheet , which retreated as glaciers , cutting the great valleys south of winterfell and the riverlands between harrenhal and the twins . the description of the jagged black mountains sounds a lot like our own rocky mountains , which were born around 60-80 million years ago . this would also mark the birth of the mountains of the moon and the high westerlands , as north and south westeros smashed together just like the fault beneath the himalayas . that violent uplift is what exposed all that lannister gold from its origin deep within the crust . that era also would have borne the iron islands . . . but we have a different iron to talk about . valyrian steel was an alloy forged in the ancient empire of the valyrians , lighter and stronger than regular steel , and whose secrets were lost during the great doom , when volcanoes torched valyria , and its dragons , into charcoal . that valyrian steel was forged with dragon fire , which is not actually a thing , but it 's almost certainly a reference to damscus steel , an ancient steel alloy developed in india around 300 bc . like valyrian steel , the secrets of its forgery were lost to history forever . speaking of dragon fire . . . what if dragons could exist ? how could a living thing breathe flames ? my buddy kyle hill came up with an interesting theory . like the tiny bombardier beetle , dragons could secrete reactive `` hypergolic '' chemicals that , when mixed , react violently and shoot out of an orifice like rocket fuel . and if dragons chewed on certain rocks and metals , which i imagine are like cupcakes to them , they could coat their teeth in minerals , creating a spark with rows of deadly knife-like flint and steel . unfortunately , our idea of a fire-breathing flying dragon is about to come crashing back down to earth , because physics . as bran stark found out the hard way , gravity seems to work in westeros just like it does here . and that means the mother of dragons ' kids are grounded . the largest bird that ever lived was the giant teratorn , with a wingspan of 7 meters . not big enough . dragons are probably more like pterosaurs . but even the largest of those , quetzalcoatlus , maxed out at 11 meters from wingtip to wingtip and 250 kg . but daenarys ' dragons are bigger than that by the time they hit puberty , and dragon lore says they never stop growing . even with a pterosaur 's hollow bones , ability to gallop on all fours to take off and huge stretchy wings , even hodor could figure out that the dragons do n't work . unless , yeah . . . magic . the wall ? wo n't work . a sheer cliff of solid ice stacked 700 feet tall would melt at the bottom under its own weight and would fall apart unless it was sloped wildfire ? works . `` greek fire '' was an ancient precursor to napalm made from petroleum , sulfur , saltpeter and was the most potent weapon of its time . add a little trimethyl borate , and you 've got a flaming death that 's ready for st. patrick 's day . milk of poppy ? works . our opiate drugs from morphine to vicodin to even heroin are all derived from the poppy plant . dire wolf ? works . the extinct canis dirus was the largest wolf to ever exist , covering north and south america , thousands have been found in the la brea tar pits alone . of course , the universe of game of thrones would live . . . or die . . . just fine whether or not it agrees with our science . but by combining the two , as raymond chandler said , the truth of art keeps science from becoming inhuman , and the truth of science keeps art from becoming ridiculous what do you think ? does bringing science into a fantasy story kill the wonder like a guest at the red wedding ? or does it help the fictional world . . . truly `` exist '' in our own ? i think it makes the story richer than a lannister . let me know what you think in the comments . and remember , a hanson always pay their debts . subscribe , and i will pay you back with a new video every week . valar morcurious .
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and 40 million years ago , westeros was likely covered by a huge ice sheet , which retreated as glaciers , cutting the great valleys south of winterfell and the riverlands between harrenhal and the twins . the description of the jagged black mountains sounds a lot like our own rocky mountains , which were born around 60-80 million years ago . this would also mark the birth of the mountains of the moon and the high westerlands , as north and south westeros smashed together just like the fault beneath the himalayas .
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how many millions of years ago were the rocky mountains created ?
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every second , one million tons of matter is blasted from the sun at the velocity of one million miles per hour , and it 's on a collision course with earth ! but do n't worry , this is n't the opening of a new michael bay movie . this is the journey of the polar lights . the northern and southern lights , also known as the aurora borealis and aurora australis , respectively , occur when high energy particles from the sun collide with neutral atoms in our atmosphere . the energy emitted from this crash produces a spectacle of light that mankind has marveled at for centuries . but the particles ' journey is n't just as simple as leaving the sun and arriving at earth . like any cross-country road trip , there 's a big detour and nobody asks for directions . let 's track this intergalactic voyage by focusing on three main points of their journey : leaving the sun , making a pit stop in the earth 's magnetic fields , and arriving at the atmosphere above our heads . the protons and electrons creating the northern lights depart from the sun 's corona . the corona is the outermost layer of the sun 's atmosphere and is one of the hottest regions . its intense heat causes the sun 's hydrogen and helium atoms to vibrate and shake off protons and electrons as if they were stripping off layers on a hot , sunny day . impatient and finally behind the wheel , these free protons and electrons move too fast to be contained by the sun 's gravity and group together as plasma , an electrically charged gas . they travel away from the sun as a constant gale of plasma , known as the solar wind . however , the earth prevents the solar wind from traveling straight into the planet by setting up a detour , the magnetosphere . the magnetosphere is formed by the earth 's magnetic currents and shields our planet from the solar winds by sending out the particles around the earth . their opportunity to continue the journey down to the atmosphere comes when the magnetosphere is overwhelmed by a new wave of travelers . this event is coronal mass ejection , and it occurs when the sun shoots out a massive ball of plasma into the solar wind . when one of these coronal mass ejections collides with earth , it overpowers the magnetosphere and creates a magnetic storm . the heavy storm stresses the magnetosphere until it suddenly snaps back , like and overstretched elastic band , flinging some of the detoured particles towards earth . the retracting band of the magnetic field drags them down to the aurora ovals , which are the locations of the northern and southern lights . after traveling 93 million miles across the galaxy , the sun 's particles finally produce their dazzling light show with the help of some friends . 20 to 200 miles above the surface , the electrons and protons meet up with oxygen and nitrogen atoms , and they sure are happy to see each other . the sun 's particles high five the atoms , giving their energy to the earth 's neutral oxygen and nitrogen atoms . when the atoms in the atmosphere are contacted by the particles , they get excited and emit photons . photons are small bursts of energy in the form of light . the colors that appear in the sky depend on the wavelength of the atom 's photon . excited oxygen atoms are responsible for the green and red colors , whereas excited nitrogen atoms produce blue and deep red hues . the collection of these interactions is what creates the northern and southern lights . the polar lights are best seen on clear nights in regions close to magnetic north and south poles . nighttime is ideal because the aurora is much dimmer than sunlight and can not be seen in daytime . remember to look up at the sky and read up on the sun 's energy patterns , specifically sunspots and solar flares , as these will be good guides for predicting the auroras .
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the energy emitted from this crash produces a spectacle of light that mankind has marveled at for centuries . but the particles ' journey is n't just as simple as leaving the sun and arriving at earth . like any cross-country road trip , there 's a big detour and nobody asks for directions .
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what is the area of the sun that shoots out particles that head towards earth ?
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so this a really beautiful sample of chromium . so chromium is a transition metal , right in the middle of the transition metals series there and it is used to protect metal components and very often you see chromium plated components on cars perhaps some of the older cars , you know , the wheel trims or perhaps the grills on the front , but if you look at the sample it is really lustrous , really beautiful and shiny . so there are some elements that one is really fond of and chromium is one of the metals that i really like . it is a metal you would have seen it in many places it is used for plating materials . this may actually be stainless steel but chromium looks very similar and it was very popular for plating bumpers , all sorts of materials in the 1930s up to the 1950s . so you can get dull chromium as well which is where the surface is very bumpy and the light tends to be absorbed a lot more and not reflected . my interest in chromium is that in the chemistry one of the very first bits of chemistry research i did in school was involving copper chromate . i spent months doing experiments on it . i did not really discover anything about it but it was great fun . at one stage i had a whole row of test tubes of copper chromate above my bed and my bedroom at home and more recently when i starting doing doctorates , i did experiments with chromium , making new complexes of chromium and one of the very first compounds that my research group ever made , that was new that nobody else had made before , was a compound of ethene and chromium - chromium pentacarbonyl ethene so i have very warm feelings about it .
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so this a really beautiful sample of chromium . so chromium is a transition metal , right in the middle of the transition metals series there and it is used to protect metal components and very often you see chromium plated components on cars perhaps some of the older cars , you know , the wheel trims or perhaps the grills on the front , but if you look at the sample it is really lustrous , really beautiful and shiny . so there are some elements that one is really fond of and chromium is one of the metals that i really like .
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why is chromium used to protect metal components , such as in the car industry on old-fashioned bumpers ( fenders ) ?
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what 's the definition of comedy ? thinkers and philosophers from plato and aristotle to hobbes , freud , and beyond , including anyone misguided enough to try to explain a joke , have pondered it , and no one has settled it . you 're lucky you found this video to sort it out . to define comedy , you should first ask why it seems comedy defies definition . the answer 's simple . comedy is the defiance of definition because definitions sometimes need defiance . consider definition itself . when we define , we use language to set borders around a thing that we 've perceived in the whirling chaos of existence . we say what the thing means and fit that in a system of meanings . chaos becomes cosmos . the universe is translated into a cosmological construct of knowledge . and let 's be honest , we need some logical cosmic order , otherwise we 'd have pure chaos . chaos can be rough , so we build a thing that we call reality . now think about logic and logos , that tight knot connecting a word and truth . and let 's jump back to thinking about what 's funny , because some people say it 's real simple : truth is funny . it 's funny because it 's true . but that 's simplistic . plenty of lies are funny . comedic fiction can be funny . made-up nonsense jibberish is frequently hilarious . for instance , florp -- hysterical ! and plenty of truths are n't funny . two plus two truly equals four , but i 'm not laughing just because that 's the case . you can tell a true anecdote , but your date may not laugh . so , why are some untruths and only some truths funny ? how do these laughable truths and untruths relate to that capital-t truth , the cosmological reality of facts and definitions ? and what makes any of them funny ? there 's a frenchman who can help , another thinker who did n't define comedy because he expressly did n't want to . henri bergson 's a french philosopher who prefaced his essay on laughter by saying he would n't define `` the comic '' because it 's a living thing . he argued laughter has a social function to destroy mechanical inelasticity in people 's attitudes and behavior . someone doing the same thing over and over , or building up a false image of themself and the world , or not adapting to reality by just noticing the banana peel on the ground -- this is automatism , ignorance of one 's own mindless rigidity , and it 's dangerous but also laughable and comic ridicule helps correct it . the comic is a kinetic , vital force , or elan vital , that helps us adapt . bergson elaborates on this idea to study what 's funny about all sorts of things . but let 's stay on this . at the base of this concept of comedy is contradiction between vital , adaptive humanity and dehumanized automatism . a set system that claims to define reality might be one of those dehumanizing forces that comedy tends to destroy . now , let 's go back to aristotle . not poetics , where he drops a few thoughts on comedy , no , metaphysics , the fundamental law of non-contradiction , the bedrock of logic . contradictory statements are not at the same time true . if a is an axiomatic statement , it ca n't be the case that a and the opposite of a are both true . comedy seems to live here , to subsist on the illogic of logical contradiction and its derivatives . we laugh when the order we project on the world is disrupted and disproven , like when the way we all act contradicts truths we do n't like talking about , or when strange observations we all make in the silent darkness of private thought are dragged into public by a good stand-up , and when cats play piano , because cats that are also somehow humans disrupt our reality . so , we do n't just laugh at truth , we laugh at the pleasurable , edifying revelation of flaws , incongruities , overlaps , and outright conflicts in the supposedly ordered system of truths we use to define the world and ourselves . when we think too highly of our thinking , when we think things are true just because we all say they 're logos and stop adapting , we become the butt of jokes played on us by that wacky little trickster , chaos . comedy conveys that destructive , instructive playfulness , but has no logical definition because it acts upon our logic paralogically from outside its finite borders . far from having a definite definition , it has an infinite infinition . and the infinition of comedy is that anything can be mined for comedy . thus , all definitions of reality , especially those that claim to be universal , logical , cosmic , capital-t truth become laughable .
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comedy is the defiance of definition because definitions sometimes need defiance . consider definition itself . when we define , we use language to set borders around a thing that we 've perceived in the whirling chaos of existence .
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what is a definition ?
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imagine being a fossil : touring the world 's great museums , inspiring awe in onlookers of all ages , posing for hordes of fawning photographers . sound like something you 'd like ? well , good luck ! at least 99.9 % of creatures that have ever lived are n't preserved in the fossil record . but forget about them , everyone else will , and listen up ! if you want your corpse in the exclusive 0.01 % club , the hall of preserved fossil fame , it will not be easy . you better work ! step one : die . it 's a cold , hard fact of fossilization . everything paleontologists find was once alive and , at some point , died . we 'll skip the details and assume you had a long , fulfilling life so we can get to what is really important -- how you die . there are many ways to become a fossil , so let 's highlight your top death options . you could get yourself trapped in tree sap , which , when hardens , turns into amber and can survive intact for millions of years . but unless you find a really big tree to sit under , amber preservation will likely remain the domain of insects and other very small animals . generally , the right place to be if you want to end up a fossil is wherever sediment is actively being deposited , like a lake or an ocean floor . a mountaintop or prairie ? not good ! you need to get buried , the faster the better , because the longer you hang around on the surface , the more likely you 'll get eaten , scavenged , or otherwise destroyed before ever having a chance to get preserved . if you can get buried someplace with little to no oxygen , like a bog or a deep lake bottom , even better . that lack of oxygen will slow down your decay and give you more time to fossilize . so , let 's say you 're lucky enough to die and get buried in a shallow sea under muddy , sandy sediments . what 's your next move ? one option is a process called permineralization . while all your soft parts decay away , your bones get saturated with mineral-rich waters . bit by bit , microscopic crystals precipitate out of these waters to fill in the empty spaces and pores in your bones . otherwise , you 'd better hope the sediments around you harden while your bones decay away and another sediment or mineral fills in the spaces your bones leave behind , creating a perfect cast of your skeleton . over time , the sediments around your fossil will lithify or turn into rock . but you 're not in the clear yet ! many things could happen to those sedimentary rocks that might destroy your chances of getting discovered . they could get uplifted into a mountain range and eroded away or carried along in an oceanic plate and subducted back into the earth 's mantle , melting your fossil into hot mush . fingers crossed your rock surroundings will get gently lifted up by plate tectonics , sea levels will change , and you 'll end up under dry land close to the surface , but not so close that erosion from wind and rain wipes you away before someone can come find you . the last step in this long process , an intrepid paleontologist has to come find you . maybe she 's a research scientist scouting for fossils your age and type or just an amateur collector hoping for a fortuitous find . she whacks away at layers of rock above you or spots your fossil exposed in a creek bank after a flood . and there you are , a magnificent scientific discovery , millions of years in the making ! she and her colleagues gently extract you from the surrounding sediment , measure and photograph all the bits and pieces they find , and begin the complex task of reconstructing how and when you lived based on the evidence they find in your bones . paleontologists will be some of your biggest fans along with all those admiring crowds at the museum . you made it ! you spent years underground in obscurity , shedding blood , sweat , tears , and your internal organs . you worked yourself to the bone until your bones disintegrated and were replaced by minerals and sediments . but it was all worth it because you 're a famous fossil ! now , you better hold that pose !
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the last step in this long process , an intrepid paleontologist has to come find you . maybe she 's a research scientist scouting for fossils your age and type or just an amateur collector hoping for a fortuitous find . she whacks away at layers of rock above you or spots your fossil exposed in a creek bank after a flood .
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if you were in charge of the mars curiosity rover and you wanted to go looking for fossils on mars , what would you look for and why ?
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death and taxes are famously inevitable , but what about decomposition ? as anyone who 's seen a mummy knows , ancient egyptians went to a lot of trouble to evade decomposition . so , how successful were they ? living cells constantly renew themselves . specialized enzymes decompose old structures , and the raw materials are used to build new ones . but what happens when someone dies ? their dead cells are no longer able to renew themselves , but the enzymes keep breaking everything down . so anyone looking to preserve a body needed to get ahead of those enzymes before the tissues began to rot . neurons die quickly , so brains were a lost cause to ancient egyptian mummifiers , which is why , according to greek historian herodotus , they started the process by hammering a spike into the skull , mashing up the brain , flushing it out the nose and pouring tree resins into the skull to prevent further decomposition . brains may decay first , but decaying guts are much worse . the liver , stomach and intestines contain digestive enzymes and bacteria , which , upon death , start eating the corpse from the inside . so the priests removed the lungs and abdominal organs first . it was difficult to remove the lungs without damaging the heart , but because the heart was believed to be the seat of the soul , they treated it with special care . they placed the visceral organs in jars filled with a naturally occurring salt called natron . like any salt , natron can prevent decay by killing bacteria and preventing the body 's natural digestive enzymes from working . but natron is n't just any salt . it 's mainly a mixture of two alkaline salts , soda ash and baking soda . alkaline salts are especially deadly to bacteria . and they can turn fatty membranes into a hard , soapy substance , thereby maintaining the corpse 's structure . after dealing with the internal organs , the priest stuffed the body cavity with sacks of more natron and washed it clean to disinfect the skin . then , the corpse was set in a bed of still more natron for about 35 days to preserve its outer flesh . by the time of its removal , the alkaline salts had sucked the fluid from the body and formed hard brown clumps . the corpse was n't putrid , but it did n't exactly smell good , either . so , priests poured tree resin over the body to seal it , massaged it with a waxy mixture that included cedar oil , and then wrapped it in linen . finally , they placed the mummy in a series of nested coffins and sometimes even a stone sarcophagus . so how successful were the ancient egyptians at evading decay ? on one hand , mummies are definitely not intact human bodies . their brains have been mashed up and flushed out , their organs have been removed and salted like salami , and about half of their remaining body mass has been drained away . still , what remains is amazingly well-preserved . even after thousands of years , scientists can perform autopsies on mummies to determine their causes of death , and possibly even isolate dna samples . this has given us new information . for example , it seems that air pollution was a serious problem in ancient egypt , probably because of indoor fires used to bake bread . cardiovascular disease was also common , as was tuberculosis . so ancient egyptians were somewhat successful at evading decay . still , like death , taxes are inevitable . when some mummies were transported , they were taxed as salted fish .
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this has given us new information . for example , it seems that air pollution was a serious problem in ancient egypt , probably because of indoor fires used to bake bread . cardiovascular disease was also common , as was tuberculosis . so ancient egyptians were somewhat successful at evading decay .
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air pollution , cardiovascular disease and tuberculosis all seemed to be problems in ancient egypt . which of these surprised you the most ? why ?
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we usually think of rhythm as an element of music , but it 's actually found everywhere in the world around us , from the ocean tides to our own heartbeats , rhythm is essentially an event repeating regularly over time . even the ticking of a clock itself is a sort of rhythm . but for musical rhythm , a steady string of repeating single beats is not enough . for that , we need at least one opposing beat with a different sound , which can be the unstressed off beat or the accented back beat . there are several ways to make these beats distinct , whether by using high and low drums , or long and short beats . which ends up being heard as the main beat is not a precise rule , but like the famous rubin 's vase , can be reversed depending on cultural perception . in standard notation , rhythm is indicated on a musical bar line , but there are other ways . remember that ticking clock ? just as its round face can trace the linear passage of time , the flow of rhythm can be traced in a circle . the continuity of a wheel can be a more intuitive way to visualize rhythm than a linear score that requires moving back and forth along the page . we can mark the beats at different positions around the circle using blue dots for main beats , orange ones for off beats , and white dots for secondary beats . here is a basic two beat rhythm with a main beat and an opposing off beat . or a three beat rhythm with a main beat , an off beat , and a secondary beat . and the spaces between each beat can be divided into further sub-beats using multiples of either two or three . layering multiple patterns using concentric wheels lets us create more complex rhythms . for example , we can combine a basic two beat rhythm with off beats to get a four beat system . this is the recognizable backbone of many genres popular around the world , from rock , country , and jazz , to reggae and cumbia . or we can combine a two beat rhythm with a three beat one . eliminating the extra main beat and rotating the inner wheel leaves us with a rhythm whose underlying feel is three-four . this is the basis of the music of whirling dervishes , as well as a broad range of latin american rhythms , such as joropo , and even bach 's famous chaconne . now if we remember rubin 's vase and hear the off beats as the main beats , this will give us a six-eight feel , as found in genres such as chacarera , and quechua , persian music and more . in an eight beat system , we have three layered circles , each rhythm played by a different instrument . we can then add an outermost layer consisting of an additive rhythmic component , reinforcing the main beat and increasing accuracy . now let 's remove everything except for this combined rhythm and the basic two beat on top . this rhythmic configuration is found as the cuban cinquillo , in the puerto rican bomba , and in northern romanian music . and rotating the outer circle 90 degrees counterclockwise gives us a pattern often found in middle eastern music , as well as brazilian choro , and argentinian tango . in all of these examples , the underlying rhythm reinforces the basic one-two , but in different ways depending on arrangement and cultural context . so it turns out that the wheel method is more than just a nifty way of visualizing complex rhythms . by freeing us from the tyranny of the bar line , we can visualize rhythm in terms of time , and a simple turn of the wheel can take us on a musical journey around the world .
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we usually think of rhythm as an element of music , but it 's actually found everywhere in the world around us , from the ocean tides to our own heartbeats , rhythm is essentially an event repeating regularly over time . even the ticking of a clock itself is a sort of rhythm . but for musical rhythm , a steady string of repeating single beats is not enough . for that , we need at least one opposing beat with a different sound , which can be the unstressed off beat or the accented back beat .
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are you able to identify any of the rhythm wheel rotations given here with riffs or figures in music you listen to ?
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most of us think of the sun as our friend . it helps plants grow , keeps us warm , and who does n't love to lie on the beach on a sunny day ? but for all of it 's good qualities , the sun can also be harmful in large amounts . that 's why we invented sunscreen . the purpose of sunscreen is to shield the body from the sun 's ultraviolet rays , which have several harmful effects , including sunburn , aging , and skin cancer promotion . these rays are separated by their different wave lengths , into types such as uva and uvb , which exert a variety of effects in the skin due to the absorption patterns of chromophores , the parts of the molecules responsible for their color . the primary two chromophores are hemoglobin , found in our red blood cells , and melanin , which gives our skin its pigment . we know that uvb rays cause the skin to burn . the role of uva rays is less well understood and appears to have an effect on our tanning response , carcinogenesis , and aging . so , how does the sunscreen protect us from these rays ? there are two basic types of sunscreen , physical and chemical blockers . physical blockers , like zinc oxide or titanium dioxide , reflect the sun 's rays by acting as a physical barrier . if you 've seen lifeguards with noses covered in white , then you know what this looks like . the same ingredients are primary components of diaper creams , where the goal is also to create a physical barrier . historically , they have n't always been easy to apply and were conspicuously visible on the skin , but new formulations have made this less of an issue . chemical blockers , on the other hand , absorb the sun 's rays . they deteriorate more quickly than physical sunscreens because their ability to absorb the sun diminishes . generally , these are more transparent when rubbed on the skin , but some people develop allergric reactions to some of the chemicals . regardless of the type of sunscreen , all are subjected to testing to determine their sunburn protection factor , or spf . this is essentially a measure of the protection that the sunscreen will provide from uvb rays before one begins to burn . but even if you do n't burn , you still need to use sunscreen because unless you live in a cave , you 're not immune to the effects of the sun . it is true that darker skinned people and those who tan easily have more built-in protection from sunburns , but they are still vulnerable to the effects of uva . children under the age of six months , on the other hand , should have almost no sun exposure as their protective mechanisms are not fully functioning , and their skin is more likely to absorb any sunscreen that is applied . wearing sunscreen helps protect against the development of all three types of skin cancer : basal cell carcinoma , squamous cell carcinoma , and melanoma . on a daily basis , the dna in your cells is developing mutations and errors that are generally handled by machinery within your cells , but ultraviolet rays from the sun lead to mutations that the cell may not be able to overcome , leading to uncontrolled growth and eventual skin cancer . the scariest thing about this is that usually you ca n't even see it happening until its too late . but if these concrete risks to your health are not enough to convince you to use sunscreen , there are aesthetic reasons as well . along with cigarette smoking , sun damage is the leading cause of premature aging . photoaging from chronic sun exposure leads to a loss of elasticity in the skin , in other words , making it look saggy . take a look at this truck driver who 's left side was chronically exposed to the sun and notice the difference . this is an important point . car windows block uvb , the burn rays , but not uva , the aging rays . it is recommended to use sunscreen daily , but you should pay special attention before prolonged sun exposure or when at the beach or among snow since the reflectivity of water and ice amplifies the sun 's rays . for these cases , apply about an ounce fifteen to thirty minutes before you go out and once again soon after you get outside . after that , you should reapply it every two to three hours , especially after swimming or sweating . otherwise you should wear protective clothing with ultraviolet protection factor , or upf . stay in shaded areas , such as under trees or an umbrella , and avoid the sun at the peak hours of 10 a.m. to 4 p.m. and what 's the best kind of sunscreen ? everyone will have their preference , but look for the following things : broad spectra , spf of at least 30 , and water-resistant . a light moisturizer with spf 30 should be good for daily use . take note if you decide to use a spray . they take several coats to effectively cover your skin , like painting a wall with a spray can versus a paint brush . so , enjoy the sun , but enjoy it with sunscreen .
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stay in shaded areas , such as under trees or an umbrella , and avoid the sun at the peak hours of 10 a.m. to 4 p.m. and what 's the best kind of sunscreen ? everyone will have their preference , but look for the following things : broad spectra , spf of at least 30 , and water-resistant . a light moisturizer with spf 30 should be good for daily use . take note if you decide to use a spray .
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spf is an abbreviation for :
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diabetes mellitus has been a scourge of the developed world with an estimated 400,000,000 people worldwide suffering from this disease , and 50 % more predicted within twenty years . its early symptoms , which include increased thirst and large volumes of urine , were recognized as far back as 1500 bce in egypt . while the term diabetes , meaning `` to pass through , '' was first used in 250 bce by the greek physician apollonius of memphis , type 1 and type 2 diabetes , associated respectively with youth and obesity , were identified as separate conditions by indian physicians somewhere in the 5th century ce . but despite the disease being known , a diagnosis of diabetes in a human patient would remain tantamount to a death sentence until the early 20th century , its causes unknown . what changed this dire situation was the help of humanity 's longtime animal partner : canis lupus familiaris , domesticated from grey wolves thousands of years ago . in 1890 , the german scientists von mering and minkowski demonstrated that removing a dog 's pancreas caused it to develop all the signs of diabetes , thus establishing the organ 's central role in the disease . but the exact mechanism by which this occurred remained a mystery until 1920 , when a young canadian surgeon named frederick banting and his student , charles best , advanced the findings of their german colleagues . working under professor macleod at the university of toronto , they confirmed that the pancreas was responsible for regulating blood glucose , successfully treating diabetic dogs by injecting them with an extract they had prepared from pancreas tissue . by 1922 , the researchers working with biochemist james collip were able to develop a similar extract from beef pancreas to first treat a 14-year-old diabetic boy , followed by six additional patients . the manufacturing process for this extract , now known as insulin , was eventually turned over to a pharmaceutical company that makes different types of injectable insulin to this day . banting and macleod received the nobel prize for medicine in 1923 for their discovery . but banting chose to share his portion with charles best , for his help in the initial studies involving dogs . but while medical experimentation on animals remains controversial , in this case at least , it was not just a matter of exploiting dogs for human needs . dogs develop diabetes at the rate of two cases per 1,000 dogs , almost the same as that of humans under 20 . most canine cases are of type 1 diabetes , similar to the type that young children develop following immune system destruction of the pancreas , and genetic studies have shown that the dog disease has many similar hallmarks of the human disease . this has allowed veterinarians to turn the tables , successfully using insulin to treat diabetes in man 's best friend for over 60 years . many dog owners commit to managing their dogs ' diabetes with insulin injected twice daily , regimented feedings , and periodic blood measurements using the same home-testing glucose monitors used by human patients . and if the purified pig insulin commonly used for dogs fails to work for a particular dog , the vet may even turn to a formulation of human insulin , bringing the process full circle . after all that dogs have done for us throughout the ages , including their role in a medical discovery that has saved countless human lives , using that same knowledge to help them is the least we could do .
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but while medical experimentation on animals remains controversial , in this case at least , it was not just a matter of exploiting dogs for human needs . dogs develop diabetes at the rate of two cases per 1,000 dogs , almost the same as that of humans under 20 . most canine cases are of type 1 diabetes , similar to the type that young children develop following immune system destruction of the pancreas , and genetic studies have shown that the dog disease has many similar hallmarks of the human disease .
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why do some breeds of dogs have a higher prevalence of diabetes than others ?
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translator : sara xiao fei reviewer : sebastian betti so , this is a map of new york state that was made in 1937 by the general drafting company . it 's an extremely famous map among cartography nerds , because down here at the bottom of the catskill mountains there is a little town called roscoe - actually , this will go easier if i just put it up here - there 's roscoe , and then , right above roscoe , is rockland , new york , and then right above that is the tiny town of agloe , new york . agloe , new york , is very famous to cartographers , because it 's a paper town . it 's also known as a copyright trap . because my map of new york and your map of new york are going to look very similar , on account of the shape of new york . often , map makers will insert fake places onto their maps , in order to protect their copyright , because then , if my fake place shows up on your map , i can be well and truly sure that you have robbed me . agloe is a scrabblization of the initials of the two guys who made this map ernest g. alpers and otto lindberg , and they released this map in 1937 . decades later , rand mcnally releases a map with agloe , new york , on it , at the same exact intersection of two dirt roads in the middle of nowhere . well , you can imagine the delight over at general drafting . they immediately called rand mcnally , and they say , `` we 've caught you ! we made agloe , new york , up . it is a fake place . it 's a paper town . we 're going to sue your pants off ! '' and rand mcnally says , `` no , no , no , no , agloe is real . '' because people kept going to that intersection of two dirt roads ( laughter ) in the middle of nowhere , expecting there to be a place called agloe , someone built a place called agloe , new york . it had a gas station , a general store , two houses at its peak . ( laughter ) and this is of course a completely irresistible metaphor to a novelist , because we would all like to believe that the stuff that we write down on paper can change the actual world in which we 're actually living - which is why my third book is called `` paper towns '' . but what interests me ultimately more than the medium in which this happened is the phenomenon itself . it 's easy enough to say that the world shapes our maps of the world , right ? like the overall shape of the world is obviously going to affect our maps . but what i find a lot more interesting is the way that the manner in which we map the world changes the world . because the world would truly be a different place if north were down . and the world would be a truly different place if alaska and russia were n't on opposite sides of the map . and the world would be a different place if we projected europe to show it in its actual size . the world is changed by our maps of the world . the way that we choose to , sort of , our personal cartographic enterprise also shapes the map of our lives , and that in turn shapes our lives . i believe that what we map changes the life we lead . and i do n't mean that in some , like , secrecy oprah 's angels network , like , you-can-think-your-way-out -of-cancer sense . but i do believe that while maps do n't show you where you will go in your life , they show you where you might go . you very rarely go to a place that is n't on your personal map . so i was a really terrible student when i was a kid . my gpa was consistently in the low 2s , and i think the reason that i was such a terrible student is that i felt like education was just a series of hurdles that had been erected before me , and i had to jump over in order to achieve adulthood . and i did n't really want to jump over these hurdles , because they seemed completely arbitrary , so i often would n't , and then people would threaten me , you know , they 'd threaten me with `` this going on my permanent record '' , or `` you 'll never get a good job '' . i did n't want a good job ! as far as i could tell at eleven or twelve years old , like , people with good jobs woke up very early in the morning , ( laughter ) and the men who had good jobs , one of the first things they did was tie a strangulation item of clothing around their necks . they literally put nooses on themselves , and then they went off to their jobs , whatever they were . that 's not a recipe for a happy life . these people - in my , symbol-obsessed , twelve-year-old imagination , these people who are strangling themselves as one of the first things they do each morning , they ca n't possibly be happy . why would i want to jump over all these hurdles and have that be the end ? that 's a terrible end ! and then , when i was in tenth grade , i went to this school , indian springs school , a small boarding school , outside of birmingham , alabama , and all at once i became a learner . and i became a learner , because i found myself in a community of learners . i found myself surrounded by people who celebrated intellectualism and engagement , and who thought that my ironic oh-so-cool disengagement was n't clever , or funny , but , like , it was a simple and unspectacular response to very complicated and compelling problems . and so i started to learn , because learning was cool . i learned that some infinite sets are bigger than other infinite sets , and i learned what iambic pentameter is and why it sounds so good to human ears . i learned that the civil war was a nationalizing conflict , i learned some physics , i learned that correlation should n't be confused with causation - all of these things , by the way , enriched my life on a literally daily basis . and it 's true that i do n't use most of them for my `` job '' , but that 's not what it 's about for me . it 's about cartography . what is the process of cartography ? it 's , you know , sailing upon some land , and thinking `` i think i 'll draw that bit of land '' , and then wondering , `` maybe there 's some more land to draw '' . and that 's when learning really began for me . it 's true that i had teachers that did n't give up on me , and i was very fortunate to have those teachers , because i often gave them cause to think there was no reason to invest in me . but a lot of the learning that i did in high school was n't about what happened inside the classroom , it was about what happened outside of the classroom . for instance , i can tell you that , `` there 's a certain slant of light , [ on ] winter afternoons , that oppresses , like the heft [ weight ] of cathedral tunes '' , not because i memorized emily dickinson in school , when i was in high school , but because there was a girl , when i was in high school , and her name was amanda , and i had a crush on her , and she liked emily dickinson poetry . the reason i can tell you what opportunity cost is , is because one day when i was playing super mario kart on my couch , my friend emmet walked in , and he said , `` how long have you been playing super mario kart ? `` , and i said , `` i do n't know , like , six hours ? `` , and he said , `` you realize that if you 'd worked at baskin-robbins those six hours , you could have made thirty dollars , so in some ways , you just paid thirty dollars to play super mario kart '' , and i was , like , `` i 'll take that deal . '' ( laughter ) but i learned what opportunity cost is , and along the way , the map of my life got better , it got bigger , it contained more places . there were more things that might happen , more futures i might have . it was n't a formal organized learning process , and i 'm happy to admit that . it was spotty , it was inconsistent , there was a lot i did n't know . i might know , you know , that cantor 's idea that some infinite sets are larger than other infinite sets , but i did n't really understand the calculus behind that idea . i might know the idea of opportunity cost , but i did n't know the law of diminishing returns . but the great thing about imagining learning as cartography , instead of imagining it as arbitrary hurdles that you have to jump over is that you see a bit of coast line , and that makes you want to see more . and so now i do know at least some of the calculus that underlies all of that stuff . so , i had one learning community in high school , then i went to another for college , and then i went to another , when i started working at a magazine called `` booklist '' , where i was an assistant surrounded by astonishingly well-read people , and then i wrote a book , and like all authors dream of doing , i promptly quit my job . and for the first time since high school , i found myself without a learning community , and it was miserable . i hated it . i read many , many books during this two-year period . i read books about stalin , and books about how the uzbek people came to identify as muslims , and i read books about how to make atomic bombs , but it just felt like i was creating my own hurdles , and then jumping over them myself , instead of feeling the excitement of being part of a community of learners , a community of people who are engaged together in a cartographic enterprise of trying to better understand and map the world around us . and then , in 2006 , i met that guy . his name is ze frank . i did n't actually meet him , just on the internet . ze frank was running , at the time , a show called `` the show with ze frank '' , and that was my way back into being a community learner again . here 's ze talking about las vegas : ( video ) ze frank : las vegas was built in the middle of a huge hot desert , almost everything here was brought from somewhere else - the sort of rocks , the trees , the waterfalls . these fish are almost as out of place as my pig that flew . contrasted to the scorching desert that surrounds this place , so are these people . things from all over the world have been rebuilt here , away from their histories , and the people that experience them differently . sometimes , improvements were made . even the sphinx got a nose job . here , what you see is what you get , and there 's no reason to feel like you 're missing anything . this new york means the same to me as it does to everyone else . everything is out of context , and that means context allows for everything . self parking , events center , shark reef . this fabrication of place could be one of the world 's greatest achievements , because no one belongs here , everyone does . as i walked around this morning , i noticed most of the buildings were huge mirrors reflecting the sun back into the desert . but unlike most mirrors , which present you with an outside view of yourself embedded in a place , these mirrors come back empty . john green : it makes me nostalgic for the days when you could see the pixels in online video . ( laughter ) ze is n't just a great public intellectual , he 's also a brilliant community builder , and the community of people that built up around these videos was in many ways a community of learners , so we played ze frank at chess collaboratively , and we beat him . we organized ourselves to take a young man on a road trip across the united states . we turned the earth into a sandwich by having one person hold a piece of bread at one point on the earth , and on the exact opposite point of the earth having another person holding a piece of bread . i realize that these are silly ideas , but they are also 'learny ' ideas , and that was what was so exciting to me , and if you go online , you can find communities like this all over the place . follow the calculus tag on tumblr , and yes , you will see people complaining about calculus , but you 'll also see people re-blogging those complaints , making the argument that calculus is interesting and beautiful , and here 's a way in to thinking about the problem that you find unsolvable . you can go to places like reddit , and find sub-reddits , like 'ask a historian ' , or 'ask science ' , where you can ask people who are in these fields a wide range of questions , from very serious ones to very silly ones . but to me , the most interesting communities of learners that are growing up on the internet right now are on youtube , and admittedly i am biased . but i think in a lot of ways , the youtube page resembles a classroom . look for instance at `` minute physics '' , a guy who 's teaching the world about physics . ( video ) let 's cut to the chase . as of july 4th , 2012 , the higgs boson is the last fundamental piece of the standard model of particle physics to be discovered experimentally . but , you might ask , why was the higgs boson included in the standard model , alongside well-known particles like electrons and photons and quarks , if it had n't been discovered back then in the 1970s ? good question . there are two main reasons . first , just like the electron is an excitation in the electron field , the higgs boson is simply a particle which is an excitation of the everywhere-permeating higgs field . the higgs field in turn plays an integral role in our model for the weak nuclear force . in particular , the higgs field helps explain why it 's so weak . we 'll talk more about this in a later video , but even though weak nuclear theory was confirmed in the 1980s , in the equations , the higgs field is so inextricably jumbled with the weak force , that until now we 've been unable to confirm its actual and independent existence . jg : or here 's a video that i made as part of my show `` crash course '' , talking about world war i : ( video ) the immediate cause was of course the assassination in sarajevo of the austrian archduke franz ferdinand , on june 28 , 1914 , by a bosnian-serb nationalist named gavrilo princip . quick aside : it 's worth noting that the first big war of the twentieth century began with an act of terrorism . so franz ferdinand was n't particularly well-liked by his uncle , the emperor franz joseph - now that is a moustache ! - but even so , the assassination led austria to issue an ultimatum to serbia , whereupon serbia accepted some , but not all , of austria 's demands , leading austria to declare war against serbia . and then russia , due to its alliance with the serbs , mobilized its army . germany , because it had an alliance with austria , told russia to stop mobilizing , which russia failed to do , so then germany mobilized its own army , declared war on russia , cemented an alliance with the ottomans , and then declared war on france , because , you know - france ! ( laughter ) and it 's not just physics and world history that people are choosing to learn through youtube . here 's a video about abstract mathematics . ( video ) so you 're me , and you 're in math class yet again , because they make you go , like , every single day . and you 're learning about , i do n't know , the sums of infinite series . that 's a high school topic , right ? which is odd , because it 's a cool topic , but they somehow manage to ruin it anyway . so i guess that 's why they allow infinite series in the curriculum . so , in a quite understandable need for distraction , you 're doodling and thinking more about what the plural of `` series '' should be than about the topic at hand . `` serieses , '' `` seriese , '' `` seriesen , '' and `` serii ? '' or is it that the singular should be changed ? one `` serie , '' or `` serus , '' or `` serum ? '' just like the singular of `` sheep '' should be `` shoop . '' but the whole concept of things like 1/2 + 1/4 + 1/8 + 1/16 and so on , approaching one , is useful if , say , you want to draw a line of elephants each holding the tail of the next one : normal elephant , young elephant , baby elephant , dog-sized elephant , puppy-sized elephant ... all the way down to mr. tusks and beyond . which is at least a tiny bit awesome , because you can get an infinite number of elephants in a line and still have it fit across a single notebook page . jg : and lastly , here 's destin , from `` smarter every day '' , talking about the conservation of angular momentum and , since it 's youtube , cats : ( video ) hey , it 's me , destin . welcome back to `` smarter every day '' . so you 've probably observed that cats almost always land on their feet . today 's question is why ? like most simple questions , there 's a very complex answer . for instance , let me reword this question : how does a cat go from feet up to feet down in a falling reference frame without violating the conservation of angular momentum ? jg : so , here 's something all of these videos have in common : they all have more than half a million views on youtube . and those are people watching not in classrooms , but because they are part of the communities of learning that are being set up by these channels . and i said earlier that youtube is like a classroom to me , and in many ways it is , because here is the instructor - it 's like the old-fashioned classroom - here 's the instructor , and then beneath the instructor is the students , and they 're all having a conversation . and i know that youtube comments have a very bad reputation in the world of the internet , but in fact , if you go on comments for these channels , what you 'll find is people engaging the subject matter , asking difficult , complicated questions that are about the subject matter , and then other people answering those questions . and because the youtube page is set up so that the place in which i 'm talking to you is on the exact same page as your comments , you are participating in a live and real and active way in the conversation . and because i 'm in comments usually , i get to participate with you , and you find this whether it 's world history , or mathematics , or science , or whatever it is . you also see young people using the tools and the sort of genres of the internet in order to create places for intellectual engagement instead of the ironic detachment that maybe most of us associate with memes and other internet conventions , you know `` got bored - invented calculus '' , or here 's honey boo boo criticizing industrial capitalism [ `` liberal capitalism is not at all the good of humanity . quite the contrary ; it is the vehicle of savage destructive nihilism '' ] . in case you ca n't see what she says ... yeah . i really believe that these spaces , these communities have become , for a new generation of learners , the kind of communities , the kind of cartographic communities that i had when i was in high school , and then again when i was in college . and as an adult , re-finding these communities has re-introduced me to a community of learners , and has encouraged me to continue to be a learner even in my adulthood , so that i no longer feel like learning is something reserved for the young . vi hart and `` minute physics '' introduced me to all kinds of things that i did n't know before . and i know that we all hearken back to the days of the parisian salon in the enlightenment , or to the algonquin round table , and wish , `` oh , i wish i could have been a part of that , i wish i could have laughed at dorothy parker 's jokes '' . but i 'm here to tell you that these places exist , they still exist . they exist in corners of the internet , where old men fear to tread . ( laughter ) and i truly , truly believe that when we invented agloe , new york , in the 1960s , when we made agloe real , we were just getting started . thank you . ( applause )
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but unlike most mirrors , which present you with an outside view of yourself embedded in a place , these mirrors come back empty . john green : it makes me nostalgic for the days when you could see the pixels in online video . ( laughter ) ze is n't just a great public intellectual , he 's also a brilliant community builder , and the community of people that built up around these videos was in many ways a community of learners , so we played ze frank at chess collaboratively , and we beat him .
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what did the four videos that john green played during his talk have in common ?
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in the summer of 1976 , a mysterious epidemic suddenly struck two central african towns , killing the majority of its victims . medical researchers suspected the deadly marburg virus to be the culprit . but what they saw in microscope images was an entirely new pathogen , which would be named after the nearby ebola river . like yellow fever or dengue , the disease caused by the ebola virus is a severe type of hemorrhagic fever . it begins by attacking the immune system 's cells and neutralizing its responses , allowing the virus to proliferate . starting anywhere from two to twenty days after contraction , initial symptoms like high temperature , aching , and sore throat resemble those of a typical flu , but quickly escalate to vomiting , rashes , and diarrhea . and as the virus spreads , it invades the lymph nodes and vital organs , such as kidneys and liver , causing them to lose function . but the virus itself is not what kills ebola victims . instead , the mounting cell deaths trigger an immune system overload , known as a cytokine storm , an explosion of immune responses that damages blood vessels , causing both internal and external bleeding . the excessive fluid loss and resulting complications can be fatal within six to sixteen days of the first symptoms , though proper care and rehydration therapy can significantly reduce mortality rates in patients . fortunately , while ebola is highly virulent , several factors limit its contagiousness . unlike viruses that proliferate through small , airborne particles , ebola only exists in bodily fluids , such as saliva , blood , mucus , vomit , or feces . in order to spread , these must be transmitted from an infected person into another 's body through passageways such as the eyes , mouth , or nose . and because the disease 's severity increases directly along with the viral load , even an infected person is unlikely to be contagious until they have begun to show symptoms . while ebola has been shown to survive on surfaces for several hours , and transmission through sneezing or coughing is theoretically possible , virtually all known cases of contraction have been through direct contact with the severely ill , with the greatest risk posed to medical workers and friends or relatives of the victims . this is why , despite its horrifying effects , ebola has been far less deadly overall than more common infections , such as measles , malaria , or even influenza . once an outbreak has been contained , the virus does not exist in the human population until the next outbreak begins . but while this is undoubtedly a good thing , it also makes ebola difficult to study . scientists believe fruit bats to be its natural carriers , but just how it is transmitted to humans remains unknown . furthermore , many of the countries where ebola outbreaks occur suffer from poor infrastructure and sanitation , which enables the disease to spread . and the poverty of these regions , combined with the relatively low amount of overall cases means there is little economic incentive for drug companies to invest in research . though some experimental medicines have shown promise , and governments are funding development of a vaccine , as of 2014 , the only widespread and effective solutions to an ebola outbreak remain isolation , sanitation , and information .
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and as the virus spreads , it invades the lymph nodes and vital organs , such as kidneys and liver , causing them to lose function . but the virus itself is not what kills ebola victims . instead , the mounting cell deaths trigger an immune system overload , known as a cytokine storm , an explosion of immune responses that damages blood vessels , causing both internal and external bleeding .
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what animals are thought to be the natural carriers of the ebola virus ?
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in the summer of 1976 , a mysterious epidemic suddenly struck two central african towns , killing the majority of its victims . medical researchers suspected the deadly marburg virus to be the culprit . but what they saw in microscope images was an entirely new pathogen , which would be named after the nearby ebola river . like yellow fever or dengue , the disease caused by the ebola virus is a severe type of hemorrhagic fever . it begins by attacking the immune system 's cells and neutralizing its responses , allowing the virus to proliferate . starting anywhere from two to twenty days after contraction , initial symptoms like high temperature , aching , and sore throat resemble those of a typical flu , but quickly escalate to vomiting , rashes , and diarrhea . and as the virus spreads , it invades the lymph nodes and vital organs , such as kidneys and liver , causing them to lose function . but the virus itself is not what kills ebola victims . instead , the mounting cell deaths trigger an immune system overload , known as a cytokine storm , an explosion of immune responses that damages blood vessels , causing both internal and external bleeding . the excessive fluid loss and resulting complications can be fatal within six to sixteen days of the first symptoms , though proper care and rehydration therapy can significantly reduce mortality rates in patients . fortunately , while ebola is highly virulent , several factors limit its contagiousness . unlike viruses that proliferate through small , airborne particles , ebola only exists in bodily fluids , such as saliva , blood , mucus , vomit , or feces . in order to spread , these must be transmitted from an infected person into another 's body through passageways such as the eyes , mouth , or nose . and because the disease 's severity increases directly along with the viral load , even an infected person is unlikely to be contagious until they have begun to show symptoms . while ebola has been shown to survive on surfaces for several hours , and transmission through sneezing or coughing is theoretically possible , virtually all known cases of contraction have been through direct contact with the severely ill , with the greatest risk posed to medical workers and friends or relatives of the victims . this is why , despite its horrifying effects , ebola has been far less deadly overall than more common infections , such as measles , malaria , or even influenza . once an outbreak has been contained , the virus does not exist in the human population until the next outbreak begins . but while this is undoubtedly a good thing , it also makes ebola difficult to study . scientists believe fruit bats to be its natural carriers , but just how it is transmitted to humans remains unknown . furthermore , many of the countries where ebola outbreaks occur suffer from poor infrastructure and sanitation , which enables the disease to spread . and the poverty of these regions , combined with the relatively low amount of overall cases means there is little economic incentive for drug companies to invest in research . though some experimental medicines have shown promise , and governments are funding development of a vaccine , as of 2014 , the only widespread and effective solutions to an ebola outbreak remain isolation , sanitation , and information .
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and as the virus spreads , it invades the lymph nodes and vital organs , such as kidneys and liver , causing them to lose function . but the virus itself is not what kills ebola victims . instead , the mounting cell deaths trigger an immune system overload , known as a cytokine storm , an explosion of immune responses that damages blood vessels , causing both internal and external bleeding .
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what do ebola victims usually die from ?
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if you 've watched the news or followed politics chances are you 've heard the term orwellian thrown around in one context or another . but have you ever stopped to think about what it really means , or why it 's used so often ? the term was named after british author eric blair known by his pen name george orwell . because his most famous work , the novel `` 1984 , '' depicts an oppressive society under a totalitarian government , `` orwellian '' is often used simply to mean authoritarian . but using the term in this way not only fails to fully convey orwell 's message , it actually risks doing precisely what he tried to warn against . orwell was indeed opposed to all forms of tyranny , spending much of his life fighting against anti-democratic forces of both the left-wing and the right . but he was also deeply concerned with how such ideologies proliferate . and one of his most profound insights was the importance that language plays in shaping our thoughts and opinions . the government of `` 1984 '' 's oceania controls its people 's actions and speech in some ways that are obvious . their every move and word is watched and heard , and the threat of what happens to those who step out of line is always looming overhead . other forms of control are not so obvious . the population is inundated with a constant barrage of propaganda made up of historical facts and statistics manufactured in the ministry of truth . the ministry of peace is the military . labor camps are called `` joycamps . '' political prisoners are detained and tortured in the ministry of love . this deliberate irony is an example of doublespeak , when words are used not to convey meaning but to undermine it , corrupting the very ideas they refer to . the regime 's control of language goes even further , eliminating words from the english language to create the official dialect of newspeak , a crudely limited collection of acronyms and simple concrete nouns lacking any words complex enough to encourage nuanced or critical thought . this has an effect on the psyche orwell calls , `` doublethink , '' a hypnotic state of cognitive dissonance in which one is compelled to disregard their own perception in place of the officially dictated version of events , leaving the individual completely dependent on the state 's definition of reality itself . the result is a world in which even the privacy of one 's own thought process is violated , where one may be found guilty of thoughtcrime by talking in their sleep , and keeping a diary or having a love affair equals a subversive act of rebellion . this might sound like something that can only happen in totalitarian regimes , but orwell was warning us about the potential for this occurring even in democratic societies . and this is why `` authoritarian '' alone does not `` orwellian '' make . in his essay , `` politics and the english language , '' he described techniques like using pretentious words to project authority , or making atrocities sound acceptable by burying them in euphemisms and convoluted sentence structures . but even more mundane abuses of language can affect the way we think about things . the words you see and hear in everyday advertising have been crafted to appeal to you and affect your behavior , as have the soundbites and talking points of political campaigns which rarely present the most nuanced perspective on the issues . and the way that we use ready-made phrases and responses gleaned from media reports or copied from the internet makes it easy to get away with not thinking too deeply or questioning your assumptions . so the next time you hear someone use the word orwellian , pay close attention . if they 're talking about the deceptive and manipulative use of language , they 're on the right track . if they 're talking about mass surveillance and intrusive government , they 're describing something authoritarian but not necessarily orwellian . and if they use it as an all-purpose word for any ideas they dislike , it 's possible their statements are more orwellian than whatever it is they 're criticizing . words have the power to shape thought . language is the currency of politics , forming the basis of society from the most common , everyday interactions to the highest ideals . orwell urged us to protect our language because ultimately our ability to think and communicate clearly is what stands between us and a world where war is peace and freedom is slavery .
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this deliberate irony is an example of doublespeak , when words are used not to convey meaning but to undermine it , corrupting the very ideas they refer to . the regime 's control of language goes even further , eliminating words from the english language to create the official dialect of newspeak , a crudely limited collection of acronyms and simple concrete nouns lacking any words complex enough to encourage nuanced or critical thought . this has an effect on the psyche orwell calls , `` doublethink , '' a hypnotic state of cognitive dissonance in which one is compelled to disregard their own perception in place of the officially dictated version of events , leaving the individual completely dependent on the state 's definition of reality itself .
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why does it matter who exerts control over language and information ? who stands to benefit ?
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what do these animals have in common ? more than you might think . along with over 5,000 other species , they 're mammals , or members of class mammalia . all mammals are vertebrates , meaning they have backbones . but mammals are distinguished from other vertebrates by a number of shared features . that includes warm blood , body hair or fur , the ability to breathe using lungs , and nourishing their young with milk . but despite these similarities , these creatures also have many biological differences , and one of the most remarkable is how they give birth . let 's start with the most familiar , placental mammals . this group includes humans , cats , dogs , giraffes , and even the blue whale , the biggest animal on earth . its placenta , a solid disk of blood-rich tissue , attaches to the wall of the uterus to support the developing embryo . the placenta is what keeps the calf alive during pregnancy . directly connected to the mother 's blood supply , it funnels nutrients and oxygen straight into the calf 's body via the umbilical cord , and also exports its waste . placental mammals can spend far longer inside the womb than other mammals . baby blue whales , for instance , spend almost a full year inside their mother . the placenta keeps the calf alive right up until its birth , when the umbilical cord breaks and the newborn 's own respiratory , circulatory , and waste disposal systems take over . measuring about 23 feet , a newborn calf is already able to swim . it will spend the next six months drinking 225 liters of its mothers thick , fatty milk per day . meanwhile , in australia , you can find a second type of mammal - marsupials . marsupial babies are so tiny and delicate when they 're born that they must continue developing in the mother 's pouch . take the quoll , one of the world 's smallest marsupials , which weighs only 18 milligrams at birth , the equivalent of about 30 sugar grains . the kangaroo , another marsupial , gives birth to a single jelly bean-sized baby at a time . the baby crawls down the middle of the mother 's three vaginas , then must climb up to the pouch , where she spends the next 6-11 months suckling . even after the baby kangaroo leaves this warm haven , she 'll return to suckle milk . sometimes , she 's just one of three babies her mother is caring for . a female kangaroo can often simultaneously support one inside her uterus and another in her pouch . in unfavorable conditions , female kangaroos can pause their pregnancies . when that happens , she 's able to produce two different kinds of milk , one for her newborn , and one for her older joey . the word mammalia means of the breast , which is a bit of a misnomer because while kangaroos do produce milk from nipples in their pouches , they do n't actually have breasts . nor do monotremes , the third and arguably strangest example of mammalian birth . there were once hundreds of monotreme species , but there are only five left : four species of echidnas and the duck-billed platypus . the name monotreme means one hole referring to the single orifice they use for reproduction , excretion , and egg-laying . like birds , reptiles , fish , dinosaurs , and others , these species lay eggs instead of giving birth to live young . their eggs are soft-shelled , and when their babies hatch , they suckle milk from pores on their mother 's body until they 're large enough to feed themselves . despite laying eggs and other adaptations that we associate more with non-mammals , like the duck-bill platypus 's webbed feet , bill , and the venomous spur males have on their feet , they are , in fact , mammals . that 's because they share the defining characteristics of mammalia and are evolutionarily linked to the rest of the class . whether placental , marsupial , or monotreme , each of these creatures and its unique birthing methods , however bizarre , have succeeded for many millennia in bringing new life and diversity into the mammal kingdom .
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take the quoll , one of the world 's smallest marsupials , which weighs only 18 milligrams at birth , the equivalent of about 30 sugar grains . the kangaroo , another marsupial , gives birth to a single jelly bean-sized baby at a time . the baby crawls down the middle of the mother 's three vaginas , then must climb up to the pouch , where she spends the next 6-11 months suckling .
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when a kangaroo gives birth to her offspring it is the size of a ( n ) __________ before it first enters her pouch .
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oh , excuse me ! have you ever yawned because somebody else yawned ? you are n't especially tired , yet suddenly your mouth opens wide and a big yawn comes out . this phenomenon is known as contagious yawning . and while scientists still do n't fully understand why it happens , there are many hypotheses currently being researched . let 's take a look at a few of the most prevalent ones , beginning with two physiological hypotheses before moving to a psychological one . our first physiological hypothesis states that contagious yawning is triggered by a specific stimulus , an initial yawn . this is called fixed action pattern . think of fixed action pattern like a reflex . your yawn makes me yawn . similar to a domino effect , one person 's yawn triggers a yawn in a person nearby that has observed the act . once this reflex is triggered , it must run its course . have you ever tried to stop a yawn once it has begun ? basically impossible ! another physiological hypothesis is known as non-conscious mimicry , or the chameleon effect . this occurs when you imitate someone 's behavior without knowing it , a subtle and unintentional copycat maneuver . people tend to mimic each other 's postures . if you are seated across from someone that has their legs crossed , you might cross your own legs . this hypothesis suggests that we yawn when we see someone else yawn because we are unconsciously copying his or her behavior . scientists believe that this chameleon effect is possible because of a special set of neurons known as mirror neurons . mirror neurons are a type of brain cell that responds equally when we perform an action as when we see someone else perform the same action . these neurons are important for learning and self-awareness . for example , watching someone do something physical , like knitting or putting on lipstick , can help you do those same actions more accurately . neuroimaging studies using fmri , functional magnetic resonance imaging , show us that when we seem someone yawn or even hear their yawn , a specific area of the brain housing these mirror neurons tends to light up , which , in turn , causes us to respond with the same action : a yawn ! our psychological hypothesis also involves the work of these mirror neurons . we will call it the empathy yawn . empathy is the ability to understand what someone else is feeling and partake in their emotion , a crucial ability for social animals like us . recently , neuroscientists have found that a subset of mirror neurons allows us to empathize with others ' feelings at a deeper level . ( yawn ) scientists discovered this empathetic response to yawning while testing the first hypothesis we mentioned , fixed action pattern . this study was set up to show that dogs would enact a yawn reflex at the mere sound of a human yawn . while their study showed this to be true , they found something else interesting . dogs yawned more frequently at familiar yawns , such as from their owners , than at unfamiliar yawns from strangers . following this research , other studies on humans and primates have also shown that contagious yawning occurs more frequently among friends than strangers . in fact , contagious yawning starts occurring when we are about four or five years old , at the point when children develop the ability to identify others ' emotions properly . still , while newer scientific studies aim to prove that contagious yawning is based on this capacity for empathy , more research is needed to shed light on what exactly is going on . it 's possible that the answer lies in another hypothesis altogether . the next time you get caught in a yawn , take a second to think about what just happened . were you thinking about a yawn ? did someone near you yawn ? was that person a stranger or someone close ? and are you yawning right now ? ( yawn ) ( lip smacking )
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dogs yawned more frequently at familiar yawns , such as from their owners , than at unfamiliar yawns from strangers . following this research , other studies on humans and primates have also shown that contagious yawning occurs more frequently among friends than strangers . in fact , contagious yawning starts occurring when we are about four or five years old , at the point when children develop the ability to identify others ' emotions properly .
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why do you think we ( humans ) start yawning contagiously when we are entering kindergarten , at about 4 or 5 years of age ?
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on our planet , we have two polar regions : the arctic , whose name comes from the greek arktikos , of the north , and the antarctic from antarktikos , opposite of the north . but there 's an easier way to remember them if you just remember what surrounds them . the arctic , situated in the northern hemisphere of our planet , is an ocean entirely surrounded by land . on the other side of the world , the antarctic is a continent entirely surrounded by ocean . so , the arctic has polar bears but no penguins , and the antarctic has penguins but no polar bears . let 's talk about the arctic first . the arctic region consists of a vast , ice-covered ocean surrounded by treeless permafrost . the area can be defined as the region between the arctic circle and the north pole . if you were to stand at the north pole , everywhere you looked , in all directions , would be south . but standing at the north pole is difficult to do for very long because it 's in the middle of an ocean , covered by constantly shifting , frozen sea ice . if you were to fall into the water at the north pole , you 'd fall into water that 's 13,980 feet deep . above the water , average winter temperatures can be as low as -40 degrees celsius , and the coldest recorded temperature is approximately -68 degrees celsius . despite these incredibly harsh conditions , humans have populated areas in the arctic for thousands of years . life in the arctic includes organisms living in the ice , zooplankton and phytoplankton , fish and marine mammals , birds , land animals , plants , and human societies . okay , what about antarctica ? antarctica is earth 's southernmost continent , and it contains the geographic south pole . it 's the fifth largest continent on the planet at nearly twice the size of australia . almost 98 % of anarctica is covered by ice at least one mile in thickness . conditions in antarctica are some of the most extreme in the entire world . on average , it 's the coldest , windiest , driest continent and has the highest average elevation of all the continents . you might think that it snows all the time at the poles , but antarctica is so dry , it 's considered a desert with annual precipitation of only 200 millimeters along the coast and far less inland . the temperature in antarctica has reached -89 degrees celsius . because it 's so harsh and hard to get to , there are no permanent human residents on antarctica , but anywhere from 1,000 to 5,000 people reside throughout the year at the research stations scattered across the continent . even the most extreme animals fight for survival , and only cold-adapted organisms survive there , including many types of algae , animals , bacteria , fungi , plants , and protista . but why is antarctica colder than its northern cousin ? well , first , much of the continent is more than three kilometers above sea level , and temperature decreases with elevation . that 's why mountaintops have snow on them . second , remember that the arctic is really a frozen ocean . the water in the ocean beneath it is warmer than the frozen ground in the antarctic , and that warmth is transferred through the ice pack . this prevents temperatures in the arctic regions from reaching the extremes typical of the land surface of antarctica . third , the seasons are conspiring against the antarctic . during the aphelion in july , when the earth is the farthest away from the sun , it also happens to be winter in the antarctic , which creates a double-whammy of cold for the southern pole . but despite being inhospitable , the north and south pole are a big reason why our planet is the way it is . both of our polar regions are very important climate controllers . they help moderate the temperature in our temperate zones and give us stable weather . as sea ice in the arctic declines due to climate change and global warming , weather around the globe becomes increasing more unstable .
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but standing at the north pole is difficult to do for very long because it 's in the middle of an ocean , covered by constantly shifting , frozen sea ice . if you were to fall into the water at the north pole , you 'd fall into water that 's 13,980 feet deep . above the water , average winter temperatures can be as low as -40 degrees celsius , and the coldest recorded temperature is approximately -68 degrees celsius .
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how deep is the water at the north pole ?
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behold the human brain , it 's lumpy landscape visibly split into a left and right side . this structure has inspired one of the most pervasive ideas about the brain , that the left side controls logic and the right , creativity . and yet , this is a myth unsupported by scientific evidence . so how did this misleading idea come about , and what does it get wrong ? it 's true that the brain has a right and a left side . this is most apparent with the outer layer , or the cortex . internal regions , like the striatum , hypothalamus , thalamus , and brain stem appear to be made from continuous tissue , but in fact , they 're also organized with left and right sides . the left and the right sides of the brain do control different body functions , such as movement and sight . the brain 's right side controls the motion of the left arm and leg and vice versa . the visual system is even more complex . each eye has a left and right visual field . both left visual fields are sent to the right side of the brain , and both right fields are sent to the left side . so the brain uses both sides to make a complete image of the world . scientists do n't know for sure why we have that crossing over . one theory is it began soon after animals developed more complex nervous systems because it gave the survival advantage of quicker reflexes . if an animal sees a predator coming from its left side , it 's best off escaping to the right . so we can say that vision and movement control are two systems that rely on this left-right structure , but problems arise when we over-extend that idea to logic and creativity . this misconception began in the mid-1800s when two neurologists , broca and wernicke , examined patients who had problems communicating due to injuries . the researchers found damage to the patients ' left temporal lobes , so they suggested that language is controlled by the left side of the brain . that captured the popular imagination . author robert louis stevenson then introduced the idea of a logical left hemisphere competing with an emotional right hemisphere represented by his characters dr. jekyll and mr. hyde . but this idea did n't hold up when doctors and scientists examined patients who were missing a hemisphere or had their two hemispheres separated . these patients showed a complete range of behaviors , both logical and creative . later research showed that one side of the brain is more active than the other for some functions . language is more localized to the left and attention to the right . so one side of the brain may do more work , but this varies by system rather than by person . there is n't any evidence to suggest that individuals have dominant sides of the brain , or to support the idea of a left-right split between logic and creativity . some people may be particularly logical or creative , but that has nothing to do with the sides of their brains . and even the idea of logic and creativity being at odds with each other does n't hold up well . solving complex math problems requires inspired creativity and many vibrant works of art have intricate logical frameworks . almost every feat of creativity and logic carries the mark of the whole brain functioning as one .
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the visual system is even more complex . each eye has a left and right visual field . both left visual fields are sent to the right side of the brain , and both right fields are sent to the left side .
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why may species have evolved both left and right visual fields within each eye ?
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every day , a sea of decisions stretches before us . some are small and unimportant , but others have a larger impact on our lives . for example , which politician should i vote for ? should i try the latest diet craze ? or will email make me a millionaire ? we 're bombarded with so many decisions that it 's impossible to make a perfect choice every time . but there are many ways to improve our chances , and one particularly effective technique is critical thinking . this is a way of approaching a question that allows us to carefully deconstruct a situation , reveal its hidden issues , such as bias and manipulation , and make the best decision . if the critical part sounds negative that 's because in a way it is . rather than choosing an answer because it feels right , a person who uses critical thinking subjects all available options to scrutiny and skepticism . using the tools at their disposal , they 'll eliminate everything but the most useful and reliable information . there are many different ways of approaching critical thinking , but here 's one five-step process that may help you solve any number of problems . one : formulate your question . in other words , know what you 're looking for . this is n't always as straightforward as it sounds . for example , if you 're deciding whether to try out the newest diet craze , your reasons for doing so may be obscured by other factors , like claims that you 'll see results in just two weeks . but if you approach the situation with a clear view of what you 're actually trying to accomplish by dieting , whether that 's weight loss , better nutrition , or having more energy , that 'll equip you to sift through this information critically , find what you 're looking for , and decide whether the new fad really suits your needs . two : gather your information . there 's lots of it out there , so having a clear idea of your question will help you determine what 's relevant . if you 're trying to decide on a diet to improve your nutrition , you may ask an expert for their advice , or seek other people 's testimonies . information gathering helps you weigh different options , moving you closer to a decision that meets your goal . three : apply the information , something you do by asking critical questions . facing a decision , ask yourself , `` what concepts are at work ? '' `` what assumptions exist ? '' `` is my interpretation of the information logically sound ? '' for example , in an email that promises you millions , you should consider , `` what is shaping my approach to this situation ? '' `` do i assume the sender is telling the truth ? '' `` based on the evidence , is it logical to assume i 'll win any money ? '' four : consider the implications . imagine it 's election time , and you 've selected a political candidate based on their promise to make it cheaper for drivers to fill up on gas . at first glance , that seems great . but what about the long-term environmental effects ? if gasoline use is less restricted by cost , this could also cause a huge surge in air pollution , an unintended consequence that 's important to think about . five : explore other points of view . ask yourself why so many people are drawn to the policies of the opposing political candidate . even if you disagree with everything that candidate says , exploring the full spectrum of viewpoints might explain why some policies that do n't seem valid to you appeal to others . this will allow you to explore alternatives , evaluate your own choices , and ultimately help you make more informed decisions . this five-step process is just one tool , and it certainly wo n't eradicate difficult decisions from our lives . but it can help us increase the number of positive choices we make . critical thinking can give us the tools to sift through a sea of information and find what we 're looking for . and if enough of us use it , it has the power to make the world a more reasonable place .
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if gasoline use is less restricted by cost , this could also cause a huge surge in air pollution , an unintended consequence that 's important to think about . five : explore other points of view . ask yourself why so many people are drawn to the policies of the opposing political candidate . even if you disagree with everything that candidate says , exploring the full spectrum of viewpoints might explain why some policies that do n't seem valid to you appeal to others .
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read the scenario below and respond to the prompt that follows . two candidates are running for president of the united states . one candidate advocates for reducing corporate taxes to incentivize businesses to open in the us , fostering the economy . the opposing candidate wishes to increase corporate tax rates to use the revenue to address domestic issues like education . describe why it is valuable and beneficial to the decision-making process to explore both political perspectives prior to casting your vote .
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( music ) eight to be great : the eight traits successful people have in common . number two : work . when i was interviewing all these successful people , they kept telling me how hard they worked . and i remember standing there thinking , `` ah , jeez , another comment about work ? why do n't they tell me the real secret to their success ? '' then finally i realized , hard work is a real secret to their success . all successful people work very hard . martha stewart said to me , `` i 'm a real hard worker . i work and work and work all the time . '' media tycoon rupert murdoch said , `` it 's all hard work . nothing comes easily . but i have a lot of fun . '' did he say fun ? yes . successful people have fun working . that 's why i say they 're not really workaholics . they 're workafrolics . jim pattison , chairman of the jim pattison group , is a workafrolic . he says , `` business is my recreation . i 'd rather go to our factories and meet with our people than go to the beach , i can tell you that . '' dave lavery , the nasa whiz who builds those robots for mars , said to me , `` we work our fingers to the bone . but it does n't seem like work . it 's fun . it 's what we want to do . we do n't want to put things down and go home . '' bill gates is a workafrolic . even after he was a multimillionaire , he worked most nights until 10 p.m. , and only took two weeks off in seven years . and he probably spent them on his computer . oprah is a workafrolic . she says , `` i never see daylight . i 'd come into work at 5:30 in the morning when it was dark , and leave at 7 or 8 when it was dark . '' i 'm a workafrolic . and over the years , i 've gone through many days and even weeks without much sleep , just because i was having so much fun . and i got ta admit , at times like that you say to yourself , `` am i the only one working this hard ? '' because there 's a myth it comes easy to some people . you turn on the tv , nobody 's working that hard . a guy like chris rock stands up on stage , tells a few jokes . what 's hard about that ? but even chris says , `` i was n't the funniest guy growing up , but i was the guy who worked on being funny the hardest . '' trust me . i 've interviewed over 500 successful people , not one of them said it came easy , even though they were doing what they loved . we tend to underestimate work and overestimate talent . but in the end , work tops talent . arthur benjamin , america 's best math whiz , said to me , `` i think numbers and i have always gotten along . but i 'm sure my 'talent ' is just due to the time and hours and work that i 've put into it . '' many talented people do n't achieve as much success as they could , unfortunately , because they sit back on their talent and never learn to work hard . that 's what happened to michael jordan when he first started playing basketball . he had the talent , but he was n't putting in the work , and the coach actually cut him from the high school basketball team . boy , that was a wake-up call . he says , `` i was very disappointed . i started working on my game the day after i was cut . '' and he soon became the hardest working player in basketball , who made fun of the other players who were n't working hard . and that hard work is what made him the greatest basketball player of all time . so i 'd say the real gift is n't talent , it 's the ability to work hard . and we tend to underestimate work and overestimate smarts . but in the end , work wins over smarts . in fact , many successful people are n't the smartest , they just work the hardest . francois parenteau , who business week called the top independent analyst on wall street , said to me , `` i 'm certainly not that smart . i ca n't even remember my own zip code . '' but he also says , `` work is a big part of my life . i think about investments pretty much 24 hours a day , seven days a week . '' nez hallett iii is ceo of smart wireless , and i thought , that 's ironic because he told me he 's not that smart . he says , `` i graduated from high school with a c average , and college with a c-minus average . '' but now the smart phd 's are reporting to him . how did he do it ? he said , `` if you 're going to be successful at anything , the key thing is to work hard . '' i 'm not smart . as proof , here 's my actual 12th grade report card . it was the only one my parents ever kept . do n't ask me why they kept it ; it 's nothing to brag about . as you can see , i was a c student , not an a student . i do n't think i 'd even make it into college these days . so how did i achieve some success and wealth ? i just worked hard , many 60- to 80-hour weeks . and now i know i 'm not alone . thomas stanley studied hundreds of millionaires , and he discovered most millionaires were n't a students , did n't score high on tests and teachers did n't think they 'd ever succeed . but they did succeed , because they worked hard . so the good news is if you 're not the smartest , if you 're a c student , not an a student , the really good news is you can still succeed . because the word `` success '' has two c 's and no a 's . ( laughter ) you can still succeed as long as you work hard . and what if you are smart ? well , i 'm sorry , there 's absolutely no hope for you . because many smart people do n't achieve as much success as they could , unfortunately , because they rest on their smarts and never learn to work hard . jeong kim , president of lucent technologies , says , `` people who are the smartest sometimes do n't realize their full potential , because things get too easy , so they do n't push themselves hard . '' after a talk i gave at one of the world 's top 10 business schools , a man came up to me and said , `` you know , when i got my mba here a few years ago , i was one of the smartest people in the class . i thought i had it made . so after i graduated , i sat back and i did n't work hard . and i went downhill . and now , at this point in my life , i 've gone nowhere . i have n't achieved any success at all . '' he said , `` thanks for the wake-up call . now i know what i need to do . i need to work . '' so the bottom line is , whether you 're smart or not , whether you 're talented or not , just keep working . ( applause )
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yes . successful people have fun working . that 's why i say they 're not really workaholics .
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`` workafrolics '' is a term used to describe successful people who have a lot of fun working and “ frolic ” in it . think about some times in your life when you were a `` workafrolic '' and worked really hard at something because it was fun . include all areas of your life . what are some ways you could make your job or lessons be as fun as your hobbies or sports ?
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if you 've ever floated on an ocean swell , you 'll know that the sea moves constantly . zoom out , and you 'll see the larger picture : our earth , covered by 71 percent water , moving in one enormous current around the planet . this intimidating global conveyor belt has many complicated drivers , but behind it all is a simple pump that moves water all over the earth . the process is called thermohaline circulation , and it 's driven by a basic concept : the concentration gradient . let 's leave the ocean for one moment and imagine we 're in an empty room with lots of roombas sardined together in one corner . turn them all on at once and the machines glide outwards bumping into and away from each other until the room is filled with an evenly spaced distribution . the machines have moved randomly towards equilibrium , a place where the concentration of a substance is equally spread out . that 's what happens along a concentration gradient , as substances shift passively from a high , or squashed , concentration , to a lower , more comfortable one . how does this relate to ocean currents and thermohaline circulation ? thermo means temperature , and haline means salt because in the real world scenario of the sea , temperature and salinity drive the shift from high to low concentrations . let 's put you back in the ocean to see how this works . snap ! you 're transformed into a molecule of surface water , off the temperate coast of new york surrounded by a zillion rowdy others . here , the sun 's rays act as an energizer that set you and the other water molecules jostling about , bouncing off each other like the roombas did . the more you spread out , the less concentrated the water molecules at the surface become . through this passive motion , you move from a high to a lower concentration . let 's suspend the laws of physics for a moment , and pretend that your molecular self can plunge deep down into the water column . in these colder depths , the comparative lack of solar warmth makes water molecules sluggish , meaning they can sit quite still at high concentrations . no jostling here . but seeking relief from the cramped conditions they 're in , they soon start moving upwards towards the roomier situation at the surface . this is how temperature drives a shift of water molecules from high to low concentrations , towards equilibrium . but sea water is made up of more than just h2o . there are a great deal of salt ions in it as well . and like you , these guys have a similar desire for spacious real estate . as the sun warms the sea , some of your fellow water molecules evaporate from the surface , increasing the ration of salt to h2o . the crowded salt ions left behind notice that lower down , salt molecules seem to be enjoying more space . and so an invasion begins , as they too move downwards in the water column . in the polar regions , we see how this small local process effects global movement . in the arctic and antarctic , where ice slabs decorate the water 's surface , there 's little temperature difference between surface and deeper waters . it 's all pretty cold . but salinity differs , and in this scenario , that 's what triggers the action . here , the sun 's rays melt surface ice , depositing a new load of water molecules into the sea . that not only increases the proximity between you and other water molecules , leaving you vying for space again , but it also conversely dilutes the concentration of salt ions . so , down you go , riding along the concentration gradient towards more comfortable conditions . for salt ions , however , their lower concentration at the surface , acts like an advertisement to the clamoring masses of salt molecules below who begin their assent . in both temperate and polar regions , this passive motion along a concentration gradient , can get a current going . and that is the starting point of the global conveyor called thermohaline circulation . this is how a simple concept becomes the mechanism underlying one of the largest and most important systems on our planet . and if you look around , you 'll see it happening everywhere . turn on a light , and it 's there . concentration gradients govern the flow of electricity , allowing electrons squashed together in one space to travel to an area of lower concentration when a channel is opened , which you do by flipping a switch . right now , in fact , there 's some gradient action going on inside you as you breath air into your lungs letting the concentrated oxygen in that air move passively out of your lungs and into your blood stream . we know that the world is filled with complex physical problems , but sometimes the first step towards understanding them can be simple . so when you confront the magnitude of the ocean 's currents , or have to figure out how electricity works , remember not to panic . understanding can be as simple as flipping a switch .
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but salinity differs , and in this scenario , that 's what triggers the action . here , the sun 's rays melt surface ice , depositing a new load of water molecules into the sea . that not only increases the proximity between you and other water molecules , leaving you vying for space again , but it also conversely dilutes the concentration of salt ions .
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in polar regions , if there is little run-off coming from glacial melt water , how do you think this will affect the overall movement of h20 and salt molecules in the water column ?
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have you ever sat in a doctor 's office for hours despite having an appointment at a specific time ? has a hotel turned down your reservation because it 's full ? or have you been bumped off a flight that you paid for ? these are all symptoms of overbooking , a practice where businesses and institutions sell or book more than their full capacity . while often infuriating for the customer , overbooking happens because it increases profits while also letting businesses optimize their resources . they know that not everyone will show up to their appointments , reservations , and flights , so they make more available than they actually have to offer . airlines are the classical example , partially because it happens so often . about 50,000 people get bumped off their flights each year . that figure comes at little surprise to the airlines themselves , which use statistics to determine exactly how many tickets to sell . it 's a delicate operation . sell too few , and they 're wasting seats . sell too many , and they pay penalties - money , free flights , hotel stays , and annoyed customers . so here 's a simplified version of how their calculations work . airlines have collected years worth of information about who does and does n't show up for certain flights . they know , for example , that on a particular route , the probability that each individual customer will show up on time is 90 % . for the sake of simplicity , we 'll assume that every customer is traveling individually rather than as families or groups . then , if there are 180 seats on the plane and they sell 180 tickets , the most likely result is that 162 passengers will board . but , of course , you could also end up with more passengers , or fewer . the probability for each value is given by what 's called a binomial distribution , which peaks at the most likely outcome . now let 's look at the revenue . the airline makes money from each ticket buyer and loses money for each person who gets bumped . let 's say a ticket costs $ 250 and is n't exchangeable for a later flight . and the cost of bumping a passenger is $ 800 . these numbers are just for the sake of example . actual amounts vary considerably . so here , if you do n't sell any extra tickets , you make $ 45,000 . if you sell 15 extras and at least 15 people are no shows , you make $ 48,750 . that 's the best case . in the worst case , everyone shows up . 15 unlucky passengers get bumped , and the revenue will only be $ 36,750 , even less than if you only sold 180 tickets in the first place . but what matters is n't just how good or bad a scenario is financially , but how likely it is to happen . so how likely is each scenario ? we can find out by using the binomial distribution . in this example , the probability of exactly 195 passengers boarding is almost 0 % . the probability of exactly 184 passengers boarding is 1.11 % , and so on . multiply these probabilities by the revenue for each case , add them all up , and subtract the sum from the earnings by 195 sold tickets , and you get the expected revenue for selling 195 tickets . by repeating this calculation for various numbers of extra tickets , the airline can find the one likely to yield the highest revenue . in this example , that 's 198 tickets , from which the airline will probably make $ 48,774 , almost 4,000 more than without overbooking . and that 's just for one flight . multiply that by a million flights per airline per year , and overbooking adds up fast . of course , the actual calculation is much more complicated . airlines apply many factors to create even more accurate models . but should they ? some argue that overbooking is unethical . you 're charging two people for the same resource . of course , if you 're 100 % sure someone wo n't show up , it 's fine to sell their seat . but what if you 're only 95 % sure ? 75 % ? is there a number that separates being unethical from being practical ?
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but , of course , you could also end up with more passengers , or fewer . the probability for each value is given by what 's called a binomial distribution , which peaks at the most likely outcome . now let 's look at the revenue .
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the probabilities in our model are given by a :
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the dna in just one of your cells gets damaged tens of thousands of times per day . multiply that by your body 's hundred trillion or so cells , and you 've got a quintillion dna errors everyday . and because dna provides the blueprint for the proteins your cells need to function , damage causes serious problems , such as cancer . the errors come in different forms . sometimes nucleotides , dna 's building blocks , get damaged , other times nucleotides get matched up incorrectly , causing mutations , and nicks in one or both strands can interfere with dna replication , or even cause sections of dna to get mixed up . fortunately , your cells have ways of fixing most of these problems most of the time . these repair pathways all rely on specialized enzymes . different ones respond to different types of damage . one common error is base mismatches . each nucleotide contains a base , and during dna replication , the enzyme dna polymerase is supposed to bring in the right partner to pair with every base on each template strand . adenine with thymine , and guanine with cytosine . but about once every hundred thousand additions , it makes a mistake . the enzyme catches most of these right away , and cuts off a few nucleotides and replaces them with the correct ones . and just in case it missed a few , a second set of proteins comes behind it to check . if they find a mismatch , they cut out the incorrect nucleotide and replace it . this is called mismatch repair . together , these two systems reduce the number of base mismatch errors to about one in one billion . but dna can get damaged after replication , too . lots of different molecules can cause chemical changes to nucleotides . some of these come from environmental exposure , like certain compounds in tobacco smoke . but others are molecules that are found in cells naturally , like hydrogen peroxide . certain chemical changes are so common that they have specific enzymes assigned to reverse the damage . but the cell also has more general repair pathways . if just one base is damaged , it can usually be fixed by a process called base excision repair . one enzyme snips out the damaged base , and other enzymes come in to trim around the site and replace the nucleotides . uv light can cause damage that 's a little harder to fix . sometimes , it causes two adjacent nucleotides to stick together , distorting the dna 's double helix shape . damage like this requires a more complex process called nucleotide excision repair . a team of proteins removes a long strand of 24 or so nucleotides , and replaces them with fresh ones . very high frequency radiation , like gamma rays and x-rays , cause a different kind of damage . they can actually sever one or both strands of the dna backbone . double strand breaks are the most dangerous . even one can cause cell death . the two most common pathways for repairing double strand breaks are called homologous recombination and non-homologous end joining . homologous recombination uses an undamaged section of similar dna as a template . enzymes interlace the damaged and undamgaed strands , get them to exchange sequences of nucleotides , and finally fill in the missing gaps to end up with two complete double-stranded segments . non-homologous end joining , on the other hand , does n't rely on a template . instead , a series of proteins trims off a few nucleotides and then fuses the broken ends back together . this process is n't as accurate . it can cause genes to get mixed up , or moved around . but it 's useful when sister dna is n't available . of course , changes to dna are n't always bad . beneficial mutations can allow a species to evolve . but most of the time , we want dna to stay the same . defects in dna repair are associated with premature aging and many kinds of cancer . so if you 're looking for a fountain of youth , it 's already operating in your cells , billions and billions of times a day .
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even one can cause cell death . the two most common pathways for repairing double strand breaks are called homologous recombination and non-homologous end joining . homologous recombination uses an undamaged section of similar dna as a template .
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telomeres are segments of dna located at the end of chromosomes and have a loop-structure due to a long 3 ' overhang . considering non homologous end joining process , can you suggest the importance of these segments ?
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there 's a factory inside you that weighs about 1.4 kilograms and runs for 24 hours a day . this is your liver , the heaviest organ in your body , and one of the most crucial . this industrious structure simultaneously acts as a storehouse , a manufacturing hub , and a processing plant . and each of these functions involve so many important subtasks that without the liver , our bodies would simply stop working . one of the liver 's main functions is to filter the body 's blood , which it receives in regular shipments from two sources : the hepatic artery delivers blood from the heart , while the hepatic portal vein brings it from the intestine . this double delivery fills the liver with nutrients , that it then sorts , processes and stores with the help of thousands of tiny internal processing plants , known as lobules . both blood flows also deliver the oxygen that the liver needs to function . the blood that is received from the intestine contains carbohydrates , fats , and vitamins and other nutrients dissolved in it from the food you 've consumed . these must be processed in different ways . in the case of carbohydrates , the liver breaks them down and converts them into sugars for the body to use as energy when the filtered blood is sent back out . sometimes the body has leftovers of nutrients that it does n't immediately require . when that happens , the liver holds some back , and stacks them in its storage facility . this facility works like a pantry for future cases when the body might be in need of nutrients . but the blood flowing into the liver is n't always full of good things . it also contains toxins and byproducts that the body ca n't use . and the liver monitors these strictly . when it spots a useless or toxic substance , it either converts it into a product that ca n't hurt the body or isolates it and whisks it away , channeling it through the kidneys and intestine to be excreted . of course , we would n't consider the liver a factory if it did n't also manufacture things . this organ makes everything from various blood plasma proteins that transport fatty acids and help form blood clots , to the cholesterol that helps the body create hormones . it also makes vitamin d and substances that help digestion . but one of its most vital products is bile . like an eco-friendly treatment plant , the liver uses cells called hepatocytes to convert toxic waste products into this bitter greenish liquid . as it 's produced , bile is funneled into a small container below the liver , called the gallbladder , before being trickled into the intestine to help break down fats , destroy microbes , and neutralize extra stomach acid . bile also helps carry other toxins and byproducts from the liver out of the body . so as you can see , the liver is an extremely efficient industrial site , performing multiple tasks that support each other . but such a complex system needs to be kept running smoothly by keeping it healthy and not overloading it with more toxins than it can handle . this is one factory we simply ca n't afford to shut down .
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as it 's produced , bile is funneled into a small container below the liver , called the gallbladder , before being trickled into the intestine to help break down fats , destroy microbes , and neutralize extra stomach acid . bile also helps carry other toxins and byproducts from the liver out of the body . so as you can see , the liver is an extremely efficient industrial site , performing multiple tasks that support each other .
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list some of the substances the liver manufactures , and why you think these may be useful for the body .
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two or three days ago , i got a letter from one of our fans and it ’ s different from any other letter that we have ever had , because this fan , young , has attached to it a sample of an element and what ’ s more it is an element that i had never seen . it ’ s scandium . it ’ s only a small piece but according to my colleague steve , it ’ s a very expensive element , so this might be quite valuable , and scandium is a really interesting element , much more interesting than i realised , when i first talked about it on the video . scandium is an element which chemists usually ignore , i have never used scandium in any of my research . it was one of the elements that mendeleev predicted ought to exist when he first devised the periodic table , when he made it there were lots of elements which were not known , but what he did was to predict that there were holes in various places where he felt that there ought to be an element and because obviously these elements did not have names , he called them ekea boron or ekea aluminium or ekea silicon meaning underneath those elements . and the triumph of the periodic table was that people actually discovered these elements . and the first one that was discovered was the element gallium ( ekea aluminium ) and the second one was ekea boron which is scandium . now you might think that it is a bit surprising because if you look at a modern periodic table , scandium and boron are really quite a long way apart but in the original way that medeleev started the periodic table when he wrote it down first , scandium and boron came very close together because both of them , have three electrons in their outer shell which makes their chemistry quite similar . of course medeleev did not know about electrons , but he guessed from looking at titanium which has four electrons and calcium which has two that he thought there was something missing and what is also interesting about these three elements that he predicted is that they all ended up with names of countries . there was gallium that was named after france , from the latin word for france . scandium that was named after , well perhaps not a country but a region , scandinavia , and then germanium , that was named after germany . the first time that an element was discovered , when gallium was discovered , people said well it was just luck , but when scandium was discovered , they really began to take mendeleev pretty seriously , and by the time germanium was discovered they really all decided that mendeleev was right . scandium , because it is an uncommon element , is one where people don ’ t know much about the chemistry . i have never really done any research in this area but like many elements suddenly there comes a time where they become really quite popular and topical and now is the time for scandium and the reason is that scandium is a really light metal . its density is slightly less than 4 , that ’ s 4 grams per cubic centimetre and that is very much lighter than most metals . copper is nearly 10 and lead and gold are close to 20 , so this is really very light . so why should metals be important if they are light , and that ’ s , the reason is sometimes you want to use a metal , but you don ’ t want the object you make to be very heavy and so for example titanium which is very light , is used for making everything from golf clubs to jet fighter planes , where you want it to be really light either so that you can swing it fast or fly fast . for scandium the reasons are rather different , people are now thinking about using hydrogen , to power cars , to use hydrogen gas , to use hydrogen gas as the fuel to power cars , but what they want to do is to store the hydrogen , in the equivalent of the petrol tank . you can ’ t just pressurise the hydrogen as in a gas cylinder because the container would be so heavy , that your car would be like a military tank it would be so heavy . so what they want to try and do is produce a chemical compound , which is a bit like a sponge that will absorb the hydrogen and then for example if you warm it gently they hydrogen will come out , and it is here that you want the metal to be light because you want this material that you are using to store hydrogen not to weigh very much . because you have got to cart it around in your car all the time , and scandium compounds are now looking really quite promising , for storage of hydrogen , and the idea is that rather like a molecular model kit , where you have balls joined with sticks , you can use organic compounds , those of carbon and hydrogen with a little oxygen , like sticks to join together scandium atoms , and produce a structure which has a lot of holes in it and then the hydrogen can go into those holes and be stored without needing an enormous pressure . sounds like an incredibly complicated way to make a fuel tank . it is quite complicated but on the other hand , if it works , you don ’ t need to understand the chemistry . you just add the hydrogen to your tank and away you go . how can you have got to your ripe old age as a chemist and never seen scandium ? well , chemists very often use compounds , salts of metals , but it ’ s not too often that you use the metal itself and salts because they don ’ t have to be purified and so on quite as much as the metals are easier to get , they are not as expensive and so there are lots of the elements which i haven ’ t seen , but i am really quite pleased with this sample of scandium , so when i am finished i am going to frame it and hang it on my wall . so we have one of my students who works with one of my colleagues , martin schroder and the student , has done his whole project , three year project , on the chemistry of scandium , so when i got this letter i asked him : have you ever seen scandium ? and he hadn ’ t , he had never seen the metal , so he was really quite excited to see john ’ s letter .
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two or three days ago , i got a letter from one of our fans and it ’ s different from any other letter that we have ever had , because this fan , young , has attached to it a sample of an element and what ’ s more it is an element that i had never seen . it ’ s scandium .
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why is the professor so happy about the letter , which had just arrived ?
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what gives the trumpet its clarion ring and the tuba its gut-shaking `` omm pah pah ? '' and what makes the trombone so jazzy ? the answer lies not in the brass these instruments are made of , but in the journey air takes from the musician 's lungs to the instrument 's bell . like any sound , music consists of vibrations traveling through air . instruments are classified based on how those vibrations are produced . percussion instruments are struck . string instruments are plucked or bowed . woodwinds have air blown against a reed or sharp edge . for brass instruments , however , the vibration come directly from the musician 's mouth . one of the first things a brass player must learn is to breathe in deeply , until every possible particle of air is crammed into the lungs . once all that air is inside , it must come out through the mouth , but there , an internal battle takes place as the musician simultaneously tries to hold their lips firmly closed while blowing enough air to force them open . the escaping air meets resistance from the lip muscles , forms an opening called the aperture and creates the vibration that brass players call `` the buzz . '' when a mouthpiece is held up to those vibrating lips , it slightly refines the buzz , amplifying the vibration at certain frequencies . but things get really interesting depending on what instrument is attached to that mouthpiece . a brass instrument 's body is essentially a tube that resonates with the air column blowing through it . the way that sound waves travel through this column forms a limited pattern of pitches known as the harmonic series , with notes spaced far apart at the lower end , but coming closer together as the pitch increases . the musician can alter the pitch of the note through slight contractions of the lips and alterations to air volume and speed . slower , warm sighing air produces lower pitches , and faster , cool , flowing air produces higher pitches in the series . but any single harmonic series has gaps where pitches are missing and the versatility of brass instruments lies in their ability to switch between multiple series . on instruments like the trumpet , valves can be lowered to increase the length of tubing the air travels through , while on a trombone , this is done by extending its slide . lengthening the tube stretches the vibrating air column , reducing the frequency of vibrations and resulting in a lower pitch . this is why the tuba , the largest brass instrument , is also the one capable of playing the lowest notes . so changing the instrument length shifts its harmonic series , while slight variations of the air flow and the player 's lips produce the different notes within it . and those notes finally emerge through the flared bell opening at the end . what started as a deep breath and a vibrating buzz on the lips has now been transformed into a bold and brassy tune . the musician 's skillful manipulation of every part of the process from lungs , to lips , to the mouthpiece , to the instrument itself creates an amazing palette of pitches that can be heard in musical genres across the globe . by harnessing the power of natural resonance in a flexible and controllable way , brass instruments are great examples of the fusion of human creativity with the physics of our world .
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instruments are classified based on how those vibrations are produced . percussion instruments are struck . string instruments are plucked or bowed .
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the percussion , the woodwind , and the brass sections all play key roles in a band . describe how each type of instrument makes its sound .
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imagine that day by day , your field of vision becomes slightly smaller , narrowing or dimming until eventually you go completely blind . we tend to think of blindness as something you 're born with , but in fact , with many diseases like retinitis pigmentosa and usher syndrome , blindness can start developing when you 're a kid , or even when you 're an adult . both of these rare genetic diseases affect the retina , the screen at the back of the eye that detects light and helps us see . now imagine if the eye could regenerate itself so that a blind person could see again . to understand if that 's possible , we need to grasp how the retina works and what it has to do with a multitalented creature named the zebrafish . the human retina is made of different layers of cells , with special neurons that live in the back of the eye called rod and cone photoreceptors . photoreceptors convert the light coming into your eye into signals that the brain uses to generate vision . people who have usher syndrome and retinitis pigmentosa experience a steady loss of these photoreceptors until finally that screen in the eye can no longer detect light nor broadcast signals to the brain . unlike most of your body 's cells , photoreceptors do n't divide and multiply . we 're born with all the photoreceptors we 'll ever have , which is why babies have such big eyes for their faces and part of why they 're so cute . but that is n't the case for all animals . take the zebrafish , a master regenerator . it can grow back its skin , bones , heart and retina after they 've been damaged . if photoreceptors in the zebrafish retina are removed or killed by toxins , they just regenerate and rewire themselves to the brain to restore sight . scientists have been investigating this superpower because zebrafish retina are also structured very much like human retina . scientists can even mimic the effects of disorders like usher syndrome or retinitis pigmentosa on the zebrafish eye . this allows them to see how zebrafish go about repairing their retinas so they might use similar tactics to fix human eyes one day , too . so what 's behind the zebrafish 's superpower ? the main players are sets of long cells that stretch across the retina called müller glia . when the photoreceptors are damaged , these cells transform , taking on a new character . they become less like müller cells and more like stem cells , which can turn into any kind of cell . then these long cells divide , producing extras that will eventually grow into new photoreceptors , travel to the back of the eye and rewire themselves into the brain . and now some researchers even think they 've found the key to how this works with the help of one of two chemicals that create activity in the brain called glutamate and aminoadipate . in mouse eyes , these make the müller glia divide and transform into photoreceptors , which then travel to the back of the retina , like they 're replenishing a failing army with new soldiers . but remember , none of this has happened in our retinas yet , so the question is how do we trigger this transformation of the müller glia in the human eye ? how can we fully control this process ? how do photoreceptors rewire themselves into the retina ? and is it even possible to trigger this in humans ? or has this mechanism been lost over time in evolution ? until we tease apart the origins of this ability , retinal regeneration will remain a mysterious superpower of the common zebrafish .
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the main players are sets of long cells that stretch across the retina called müller glia . when the photoreceptors are damaged , these cells transform , taking on a new character . they become less like müller cells and more like stem cells , which can turn into any kind of cell . then these long cells divide , producing extras that will eventually grow into new photoreceptors , travel to the back of the eye and rewire themselves into the brain .
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before they divide , muller cells transform to become more like :
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wars are a tragic part of our history and will almost certainly be a tragic part of our future . since the establishment of the united nations , wars of aggression have been outlawed and multilateral conventions refer to armed conflict instead of war . but the wars of the future wo n't be like the wars of our past . alongside traditional warfare , our future will include cyberwarfare , remotely fighting our enemies through the use of a new class of weapons , including computer viruses and programs to alter the enemy 's ability to operate . and not only is cyberwarfare not covered by existing legal frameworks , but the question of what exactly constitutes cyberwarfare is still highly debated . so , how can we deal with cyberwarfare if we ca n't even agree on what it means ? one way forward is to envision situations where new international laws may be needed . imagine a new kind of assassin , one that could perpetrate a crime without firing a single shot or even being in the same country . for example , an individual working for the government uses a wireless device to send a signal to another foreign leader 's pacemaker . this device directs the pacemaker to malfunction , ultimately resulting in the foreign leader 's death . would this cyber assassination constitute an act of war ? as a second example , imagine an allied group of nations cooperatively infiltrating the computer systems of an enemy nation 's nuclear warship . this attack results in a nuclear-powered aircraft carrier almost melting down , which was stopped just short of killing thousands of soldiers and civilians . as a defensive measure , the enemy country responds by unleashing a defensive cyberattack that results in the allied nations ' power grids going down . hospitals can no longer treat patients , entire regions without heat or clean water , all ultimately causing tens of thousands civilian deaths . the origin of the power failure was the counterattack , but the fragile infrastructure , feeble cybersecurity , and the antiquated state of the power grid all contributed to the deaths of the civilians . could the country fight back ? who would they fight ? and would their retaliation be considered an act of war ? do they constitute war crimes against humanity ? who is to be held responsible ? the computer programmers who wrote the code ? the military project manager who oversaw the creation of the code ? the commander who hit the button , setting off the event ? the hardware engineer who created the computers , knowing that they were intended to enable an attack ? because war has been with us for so long , we have laws to deal with figuring out who should be held accountable for their actions in combat . these legal frameworks aim to contain and prevent atrocities from being more atrocious . commandeering civilian planes and using them as weapons , dropping atomic bombs , the use of gas chambers or poisonous gas in conflict , all of these actions , if committed , constitute acts of war and war crimes under customary international law and the hague conventions . again , the current legal framework stays silent on hypothetical questions and countless others because there are no easy answers , and there are only two ways to make progress on these questions : peace or new laws . so , what hypothetical but plausible scenarios can you imagine falling under the burgeoning definition of cyberwarfare , and how might you design an international legal framework to deter these activities ?
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this device directs the pacemaker to malfunction , ultimately resulting in the foreign leader 's death . would this cyber assassination constitute an act of war ? as a second example , imagine an allied group of nations cooperatively infiltrating the computer systems of an enemy nation 's nuclear warship .
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what is the name of the un rules of cyber engagement ?
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for as far back as we can trace our existence , humans have been fascinated with death and resurrection . nearly every religion in the world has some interpretation of them , and from our earliest myths to the latest cinematic blockbusters , the dead keep coming back . but is resurrection really possible ? and what is the actual difference between a living creature and a dead body , anyway ? to understand what death is , we need to understand what life is . one ancient theory was an idea called vitalism , which claimed that living things were unique because they were filled with a special substance , or energy , that was the essence of life . whether it was called qi , lifeblood , or humors , the belief in such an essence was common throughout the world , and still persists in the stories of creatures who can somehow drain life from others , or some form of magical sources that can replenish it . vitalism began to fade in the western world following the scientific revolution in the 17th century . rené descartes advanced the notion that the human body was essentially no different from any other machine , brought to life by a divinely created soul located in the brain 's pineal gland . and in 1907 , dr. duncan mcdougall even claimed that the soul had mass , weighing patients immediately before and after death in an attempt to prove it . though his experiments were discredited , much like the rest of vitalism , traces of his theory still come up in popular culture . but where do all these discredited theories leave us ? what we now know is that life is not contained in some magical substance or spark , but within the ongoing biological processes themselves . and to understand these processes , we need to zoom down to the level of our individual cells . inside each of these cells , chemical reactions are constantly occurring , powered by the glucose and oxygen that our bodies convert into the energy-carrying molecule known as atp . cells use this energy for everything from repair to growth to reproduction . not only does it take a lot of energy to make the necessary molecules , but it takes even more to get them where they need to be . the universal phenomenon of entropy means that molecules will tend towards diffusing randomly , moving from areas of high concentration to low concentration , or even breaking apart into smaller molecules and atoms . so cells must constantly keep entropy in check by using energy to maintain their molecules in the very complicated formations necessary for biological functions to occur . the breaking down of these arrangements when the entire cell succumbs to entropy is what eventually results in death . this is the reason organisms ca n't be simply sparked back to life once they 've already died . we can pump air into someone 's lungs , but it wo n't do much good if the many other processes involved in the respiratory cycle are no longer functioning . similarly , the electric shock from a defibrillator does n't jump-start an inanimate heart , but resynchronizes the muscle cells in an abnormally beating heart so they regain their normal rhythm . this can prevent a person from dying , but it wo n't raise a dead body , or a monster sewn together from dead bodies . so it would seem that all our various medical miracles can delay or prevent death but not reverse it . but that 's not as simple as it sounds because constant advancements in technology and medicine have resulted in diagnoses such as coma , describing potentially reversible conditions , under which people would have previously been considered dead . in the future , the point of no return may be pushed even further . some animals are known to extend their lifespans or survive extreme conditions by slowing down their biological processes to the point where they are virtually paused . and research into cryonics hopes to achieve the same by freezing dying people and reviving them later when newer technology is able to help them . see , if the cells are frozen , there 's very little molecular movement , and diffusion practically stops . even if all of a person 's cellular processes had already broken down , this could still conceivably be reversed by a swarm of nanobots , moving all the molecules back to their proper positions , and injecting all of the cells with atp at the same time , presumably causing the body to simply pick up where it left off . so if we think of life not as some magical spark , but a state of incredibly complex , self-perpetuating organization , death is just the process of increasing entropy that destroys this fragile balance . and the point at which someone is completely dead turns out not to be a fixed constant , but simply a matter of how much of this entropy we 're currently capable of reversing .
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but where do all these discredited theories leave us ? what we now know is that life is not contained in some magical substance or spark , but within the ongoing biological processes themselves . and to understand these processes , we need to zoom down to the level of our individual cells .
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how can one preserve cellular biological materials ?
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you might think you know a lot about native americans through popular movies , books , and classes in school , but it turns out that a lot of what we think we know about famous native american figures is n't quite right . take sacajawea for example . you probably remember her as a beautiful indian woman who lived an exotic life serving as the all-knowing guide for lewis and clark 's famous expedition , right ? well , that 's not exactly how it happened . not much is known about sacajawea 's early childhood , but we do know that she was born in 1788 into the agaidika tribe of the lemhi shoshone in what is now idaho . in 1800 , when she was about 12 years old , sacajawea and several other girls were kidnapped by a group of hidatsa indians . she was taken as a captive to a hidatsa village in present-day north dakota . then , she was sold to a french canadian fur trapper named toussaint charbonneau . within a year or so , she was pregnant with her first child . soon after she became pregnant , the corps of discovery arrived near the hidatsa villages . captains meriwether lewis and william clark built fort mandan there , and then started interviewing people to help guide them on their perilous expedition . they agreed to hire sacajawea 's husband , charbonneau , with the understanding that his lovely wife would also come along as an interpreter . they figured her very presence would help any encounters with native tribes along the way . as clark noted in his journal , `` a woman with a party of men is a token of peace . '' shortly thereafter , sacajawea gave birth to a little boy named jean baptiste charbonneau . clark called him pompy . she carried pompy on a board strapped to her back as the corps of discovery forged on . besides interpreting the language when lewis and clark encountered indians , sacajawea 's activities as a member of the corps included digging for roots , collecting edible plants , and picking berries . in 1805 , the boat they were riding in was capsized . she dove into the water , recovering all the important papers and supplies that would otherwise have been lost , including the journals and records of lewis and clark . later that year , captain lewis and three men scouted 75 miles ahead of the expedition 's main party , crossing the continental divide . the next day they encountered a group of shishones . not only did they prove to be sacajawea 's band , but their leader , chief cameahwait , turned out to be her very own brother . after five years of separation since her kidnapping as a young girl , sacajawea and cameahwait had an emotional reunion . unfortunately , she quickly had to bid farewell to her beloved brother and continue on with the journey . at one point , the expedition became so difficult and freezing , the group was reduced to eating candles to survive . when temperatures finally became more bearable , sacajawea found , dug , and cooked roots to help the group regain their strength . on the return trip , they encountered an indian wearing a beautiful fur robe . lewis and clark wanted to bring the robe to thomas jefferson as a gift but had nothing to trade for it . so , sacajawea agreed to trade her most precious possession , her beaded belt , for the fur . a little over two years after the expedition began , it was finally over , ending in st. louis . today , we learn about sacajawea in school as a heroic guide , but her life , like most everyone 's , was much more complicated than history books sometimes give her credit for .
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as clark noted in his journal , `` a woman with a party of men is a token of peace . '' shortly thereafter , sacajawea gave birth to a little boy named jean baptiste charbonneau . clark called him pompy .
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sacajawea gave birth during the expedition to a little boy she named jean baptiste , also known as “ pomp. ” she carried her baby on her back for the remainder of the journey . do you think having a baby slowed down the expedition ? how might having an infant during such a trip change things ? do you think having pompy along helped or hurt the journey ?
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so this a really beautiful sample of chromium . so chromium is a transition metal , right in the middle of the transition metals series there and it is used to protect metal components and very often you see chromium plated components on cars perhaps some of the older cars , you know , the wheel trims or perhaps the grills on the front , but if you look at the sample it is really lustrous , really beautiful and shiny . so there are some elements that one is really fond of and chromium is one of the metals that i really like . it is a metal you would have seen it in many places it is used for plating materials . this may actually be stainless steel but chromium looks very similar and it was very popular for plating bumpers , all sorts of materials in the 1930s up to the 1950s . so you can get dull chromium as well which is where the surface is very bumpy and the light tends to be absorbed a lot more and not reflected . my interest in chromium is that in the chemistry one of the very first bits of chemistry research i did in school was involving copper chromate . i spent months doing experiments on it . i did not really discover anything about it but it was great fun . at one stage i had a whole row of test tubes of copper chromate above my bed and my bedroom at home and more recently when i starting doing doctorates , i did experiments with chromium , making new complexes of chromium and one of the very first compounds that my research group ever made , that was new that nobody else had made before , was a compound of ethene and chromium - chromium pentacarbonyl ethene so i have very warm feelings about it .
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so this a really beautiful sample of chromium . so chromium is a transition metal , right in the middle of the transition metals series there and it is used to protect metal components and very often you see chromium plated components on cars perhaps some of the older cars , you know , the wheel trims or perhaps the grills on the front , but if you look at the sample it is really lustrous , really beautiful and shiny .
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find chromium in the periodic table and look at its electronic configuration . is there anything strange about the electrons ?
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can you imagine a party where every movement , from the slightest gesture to walking across the room , and every visual detail , from furniture to hemline length , were governed by a complex system of rules and procedures ? for centuries , such rituals were commonplace for european nobility . and while they 've gone out of fashion , we recognize the components under a familiar label : ballet . ballet , from italian `` balletto , '' or little dance , originated in renaissance italy as a combination of social dance and choreographed display at aristocratic gatherings . in many aspects , it was a way of controlling people in court with acceptable forms of behavior , such as the manner in which people stepped , bowed , or took someone 's hand . it also involved rules governing everything from attire to where one could walk or sit in relation to the king . over time , the study of ballet became a central element of court life , and proper grasp of the etiquette could make or break one 's success as a courtier . many of these court gestures can still be seen in modern ballet techniques . ballet was brought to france in the 16th century by catherine de ' medici , the italian wife of king henry ii . as celebrations became more lavish , so did the dance , with dancing masters teaching elaborate steps to young nobles and story elements providing a unifying theme . the focus shifted from participation to performance , and the form acquired more theatrical trappings , such as professionally designed sets and a slightly raised platform or stage with curtains and wings . but it was in the 17th century court of louis xiv that ballet was refined into the art we know today . louis himself had been trained in ballet from childhood . his early role as the sun god apollo at age fifteen cemented the central role ballet would play during his reign . it also earned him the title of sun king , with his splendid golden costume and choreography that promoted the idea of the king as a divinely ordained ruler . louis would go on to perform 80 roles in 40 major ballets , either as a majestic lead , or sometimes playing minor or comedic parts before emerging in the lead role as the end . he trained daily in ballet , as well as fencing and riding , and through his example , dancing became an essential skill for all gentlemen of the era . but louis xiv 's main contribution to ballet was not as a performer . his founding of the royal academy of dance in 1661 shifted control of ballet from local guilds to the royal court . as director , he appointed his personal ballet master and frequent performance partner pierre beauchamp , who codified the five main positions of the body still used today . through is collaborations with jean-baptiste lully , the director of the royal music academy , and famed playwright molière , beauchamp helped establish ballet as a grand spectacle . and in 1669 , a separate ballet academy was founded . the paris opera ballet survives today as the oldest ballet company in the world . ballet moved away from the royal court to the theater and survived the democratic revolutions and reforms that followed over the next century . with the advent of the romantic movement , fantasy and folklore themes became common motifs . and though the influence of ballet in france would decline , other countries , such as russia , would play a major role in its further development . fortunately , today most of us do n't have to learn a complicated set of steps just to socialize at a wedding . instead , we can go to the theater to see professionals who spend their lives training rigorously to perform feats that would have been unimagineable in louis xiv 's day .
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he trained daily in ballet , as well as fencing and riding , and through his example , dancing became an essential skill for all gentlemen of the era . but louis xiv 's main contribution to ballet was not as a performer . his founding of the royal academy of dance in 1661 shifted control of ballet from local guilds to the royal court .
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king louis xiv was best known for his role as :
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every day of your life , you move through systems of power that other people made . do you sense them ? do you understand power ? do you realize why it matters ? power is something we are often uncomfortable talking about . that 's especially true in civic life , how we live together in community . in a democracy , power is supposed to reside with the people , period . any further talk about power and who really has it seems a little dirty , maybe even evil . but power is no more inherently good or evil than fire or physics . it just is . it governs how any form of government works . it determines who gets to determine the rules of the game . so learning how power operates is key to being effective , being taken seriously , and not being taken advantage of . in this lesson , we 'll look at where power comes from , how it 's exercised and what you can do to become more powerful in public life . let 's start with a basic definition . power is the ability to make others do what you would have them do . of course , this plays out in all arenas of life , from family to the workplace to our relationships . our focus is on the civic arena , where power means getting a community to make the choices and to take the actions that you want . there are six main sources of civic power . first , there 's physical force and a capacity for violence . control of the means of force , whether in the police or a militia , is power at its most primal . a second core source of power is wealth . money creates the ability to buy results and to buy almost any other kind of power . the third form of power is state action , government . this is the use of law and bureaucracy to compel people to do or not do certain things . in a democracy , for example , we the people , theoretically , give government its power through elections . in a dictatorship , state power emerges from the threat of force , not the consent of the governed . the fourth type of power is social norms or what other people think is okay . norms do n't have the centralized machinery of government . they operate in a softer way , peer to peer . they can certainly make people change behavior and even change laws . think about how norms around marriage equality today are evolving . the fifth form of power is ideas . an idea , individual liberties , say , or racial equality , can generate boundless amounts of power if it motivates enough people to change their thinking and actions . and so the sixth source of power is numbers , lots of humans . a vocal mass of people creates power by expressing collective intensity of interest and by asserting legitimacy . think of the arab spring or the rise of the tea party . crowds count . these are the six main sources of power , what power is . so now , let 's think about how power operates . there are three laws of power worth examining . law number one : power is never static . it 's always either accumulating or decaying in a civic arena . so if you are n't taking action , you 're being acted upon . law number two : power is like water . it flows like a current through everyday life . politics is the work of harnessing that flow in a direction you prefer . policymaking is an effort to freeze and perpetuate a particular flow of power . policy is power frozen . law number three : power compounds . power begets more power , and so does powerlessness . the only thing that keeps law number three from leading to a situation where only one person has all the power is how we apply laws one and two . what rules do we set up so that a few people do n't accumulate too much power , and so that they ca n't enshrine their privilege in policy ? that 's the question of democracy , and you can see each of these laws at work in any news story . low wage workers organize to get higher pay . oil companies push to get a big pipeline approved . gay and lesbian couples seek the legal right to marry . urban parents demand school vouchers . you may support these efforts or not . whether you get what you want depends on how adept you are with power , which brings us finally to what you can do to become more powerful in public life . here , it 's useful to think in terms of literacy . your challenge is to learn how to read power and write power . to read power means to pay attention to as many texts of power as you can . i do n't mean books only . i mean seeing society as a set of texts . do n't like how things are in your campus or city or country ? map out who has what kind of power , arrayed in what systems . understand why it turned out this way , who 's made it so , and who wants to keep it so . study the strategies others in such situations used : frontal attack or indirection , coalitions or charismatic authority . read so you may write . to write power requires first that you believe you have the right to write , to be an author of change . you do . as with any kind of writing , you learn to express yourself , speak up in a voice that 's authentic . organize your ideas , then organize other people . practice consensus building . practice conflict . as with writing , it 's all about practice . every day you have a chance to practice , in your neighborhood and beyond . set objectives , then bigger ones . watch the patterns , see what works . adapt , repeat . this is citizenship . in this short lesson , we 've explored where civic power comes from , how it works and what you can do to exercise it . one big question remaining is the `` why '' of power . do you want power to benefit everyone or only you ? are your purposes pro-social or anti-social ? this question is n't about strategy . it 's about character , and that 's another set of lessons . but remember this : power plus character equals a great citizen , and you have the power to be one .
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so now , let 's think about how power operates . there are three laws of power worth examining . law number one : power is never static .
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create a table differentiating between the three laws of power .
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( music ) the eight traits successful people have in common . number one : passion . successful people love what they do . when i asked russell crowe what led to his academy award for best actor , he said , `` the bottom line is i love the actual job of acting . i have a great passion for it . '' successful people in all fields love what they do , whether it 's astrophysicist jaymie matthews , author j.k. rowling or athlete michael phelps . and not just big names -- margaret macmillan , a history professor , says , `` i spent my life doing what i loved . '' carlos , a bus driver i sit with at starbucks , says , `` i love what i do . i 've only missed three days in four years . '' and believe it or not , even successful dentists love what they do . izzy novak says , `` i love dentistry . i ca n't imagine being anything else . '' but what about business ? many of you are in business , and we tend to think that business is more about cold numbers than hot passion , more about logic than love , so what surprised me was how often successful business people actually use the words `` passion '' or `` love '' when they talk about their work . when jack welch was ceo of general electric , he was asked if he liked his job . he said , `` no , i do n't like this job . i love this job . '' we can have passion for a profession . kathleen lane , chief strategist at workcar , says , `` i 've found a profession i love . '' she also says , `` stress is n't working 15 hours at a job you like , stress is working 15 minutes at a job you dislike . '' we can have a passion for people . nez hallett iii , ceo of smart wireless , says , `` i used to be in sales . now i 'm a ceo . i just love being around people . '' we can have passion for a product . james dyson , the vacuum cleaner guy , says , `` i love vacuum cleaners , and i will love them until the day i die . '' ( laughter ) yup , when he dies , they 're just going to cremate him and suck up those ashes with a dyson vacuum , and place it on the shelf . ( laughter ) we can have passion for a particular field . anita roddick , the great founder of the body shop , once said , `` i love retailing . i love buying and selling and making connections . '' she also said , `` i do n't like systems , financial sheets or plans . '' yes , no matter how much we love what we do , there 's always going to be stuff we do n't love . the trick is to make sure the stuff you do n't love only takes up 20 percent of your time , and the stuff you do love takes up 80 . if it 's the other way around , we 're in the wrong job . passion is sometimes mistaken for ambition . people call donald trump ambitious , but he says , `` i 'm not ambitious . i just love what i do . and if you love what you do , you do a lot of stuff . and then people say , 'oh , you 're ambitious . ' '' the cool thing about passion is it turns underachievers into superachievers . i have a long list of famous underachievers -- like albert einstein -- who people said would go nowhere when they were young . for instance , who said this , besides me ? `` i was sitting in my room being a depressed guy , trying to figure out what i was doing with my life . '' turns out it was bill gates . bill was such an underachiever , his parents actually sent him to counseling . yeah , i can just hear the neighbors back then saying , `` jeez , that gates kid . what a loser . he 's never going to go anywhere . '' and he did n't , until he discovered his passion for software . the big problem is finding your passion . sure , there 's the kid that knows they want to be an accountant or an architect or an astronaut from the time they 're 10 , but i found a much bigger group of successful people who , when they were young , and even when they were older , did n't have a clue what their passion was , and it took them a long time to find it or to fall into it . dawn lepore , chief information officer at charles schwab , said to me , `` i fell into what i do , and i did n't know i loved it until i fell into it . '' and i hear that a lot . so how do people find their passion ? well they just get out there and try a lot of stuff and explore many paths . robert munsch explored many paths . he said to me , `` i studied to be a priest and that turned out to be a disaster . i tried working on a farm . they did n't like me . i worked on a boat . it sank . i tried a lot of things that did n't work , but i kept trying and then i tried something that did work . '' and i 'd say it worked ; as a children 's author , he 's sold over 40 million books . yes , finding a job we love is like finding a person we love . sometimes we 've just got to go on a lot of really bad dates before we find the right one . now , i read a survey of 18- to 25-year-olds , and 81 percent said their first or second life goal was to get rich . and i thought , boy , they 've got it all wrong . because i 've interviewed many millionaires and billionaires , and guess how many of them said their life goal was to get rich ? zero ! they did n't do it for money , they did it for love . they went for the zing , not the ka-ching ka-ching . when bill gates and paul allen started microsoft , they did n't do it for the money . bill says , `` paul and i never thought we 'd make much money . we just loved writing software . '' and with that attitude , he became the richest man in the world . j.k. rowling did n't write harry potter books for the money . she said , `` i love writing these books . i just wanted to make enough money to continue to write . '' and with that attitude , she became a billionaire . i became a millionaire by following my heart , not my wallet , and a number of times i walked away from great-paying jobs to do poor-paying jobs i loved better . once was when i had a great job , traveling the world , making a lot of money , but i was n't doing the one thing i loved at the time , which was photography . so i said , i think i 'll leave and start my own little photo company . my heart said , yeah ! go for it . my wallet , and all my friends , i might add , said , are you crazy ? you ca n't walk away from all the money ! you 'll starve . i did n't listen to them . i walked away , and yeah , at first there was n't much money , but it did n't matter , because i was having fun doing what i loved . and eventually , the money came , and much more than if i 'd stayed in my old job . so i learned it 's true , what they say : if you do what you love , the money comes anyway . so i 'd say if you really want to get rich , put money at the bottom of your goals list and passion at the top . and why does it work that way ? because if you love what you do , you automatically do the other seven things that lead to success and wealth . you will work hard , you will push yourself , you will persist . and what if you 're in a job you do n't love ? well , just follow your passion on the side . remember , albert einstein was a patent clerk . that was his job , but his passion was physics . and he wrote four of his most important papers in his spare time as a hobby , and became one of the world 's greatest scientists . so it 's amazing what you can do if you love what you do . ( applause )
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passion is sometimes mistaken for ambition . people call donald trump ambitious , but he says , `` i 'm not ambitious . i just love what i do .
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people call donald trump ambitious , but he says :
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have you ever talked with a friend about a problem only to realize that he just does n't seem to grasp why the issue is so important to you ? have you ever presented an idea to a group and it 's met with utter confusion ? or maybe you 've been in an argument when the other person suddenly accuses you of not listening to what they 're saying at all ? what 's going on here ? the answer is miscommunication , and in some form or another , we 've all experienced it . it can lead to confusion , animosity , misunderstanding , or even crashing a multimillion dollar probe into the surface of mars . the fact is even when face-to-face with another person , in the very same room , and speaking the same language , human communication is incredibly complex . but the good news is that a basic understanding of what happens when we communicate can help us prevent miscommunication . for decades , researchers have asked , `` what happens when we communicate ? '' one interpretation , called the transmission model , views communication as a message that moves directly from one person to another , similar to someone tossing a ball and walking away . but in reality , this simplistic model does n't account for communication 's complexity . enter the transactional model , which acknowledges the many added challenges of communicating . with this model , it 's more accurate to think of communication between people as a game of catch . as we communicate our message , we receive feedback from the other party . through the transaction , we create meaning together . but from this exchange , further complications arise . it 's not like the star trek universe , where some characters can vulcan mind meld , fully sharing thoughts and feelings . as humans , we ca n't help but send and receive messages through our own subjective lenses . when communicating , one person expresses her interpretation of a message , and the person she 's communicating with hears his own interpretation of that message . our perceptual filters continually shift meanings and interpretations . remember that game of catch ? imagine it with a lump of clay . as each person touches it , they shape it to fit their own unique perceptions based on any number of variables , like knowledge or past experience , age , race , gender , ethnicity , religion , or family background . simultaneously , every person interprets the message they receive based on their relationship with the other person , and their unique understanding of the semantics and connotations of the exact words being used . they could also be distracted by other stimuli , such as traffic or a growling stomach . even emotion might cloud their understanding , and by adding more people into a conversation , each with their own subjectivities , the complexity of communication grows exponentially . so as the lump of clay goes back and forth from one person to another , reworked , reshaped , and always changing , it 's no wonder our messages sometimes turn into a mush of miscommunication . but , luckily , there are some simple practices that can help us all navigate our daily interactions for better communication . one : recognize that passive hearing and active listening are not the same . engage actively with the verbal and nonverbal feedback of others , and adjust your message to faciliate greater understanding . two : listen with your eyes and ears , as well as with your gut . remember that communication is more than just words . three : take time to understand as you try to be understood . in the rush to express ourselves , it 's easy to forget that communication is a two-way street . be open to what the other person might say . and finally , four : be aware of your personal perceptual filters . elements of your experience , including your culture , community , and family , influence how you see the world . say , `` this is how i see the problem , but how do you see it ? '' do n't assume that your perception is the objective truth . that 'll help you work toward sharing a dialogue with others to reach a common understanding together .
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have you ever talked with a friend about a problem only to realize that he just does n't seem to grasp why the issue is so important to you ? have you ever presented an idea to a group and it 's met with utter confusion ?
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which of these activities is the most intentional ?
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how do schools of fish swim in harmony ? and how do the tiny cells in your brain give rise to the complex thoughts , memories , and consciousness that are you ? oddly enough , those questions have the same general answer : emergence , or the spontaneous creation of sophisticated behaviors and functions from large groups of simple elements . like many animals , fish stick together in groups , but that 's not just because they enjoy each other 's company . it 's a matter of survival . schools of fish exhibit complex swarming behaviors that help them evade hungry predators , while a lone fish is quickly singled out as easy prey . so which brilliant fish leader is the one in charge ? actually , no one is , and everyone is . so what does that mean ? while the school of fish is elegantly twisting , turning , and dodging sharks in what looks like deliberate coordination , each individual fish is actually just following two basic rules that have nothing to do with the shark : one , stay close , but not too close to your neighbor , and two , keep swimmming . as individuals , the fish are focused on the minutiae of these local interactions , but if enough fish join the group , something remarkable happens . the movement of individual fish is eclipsed by an entirely new entity : the school , which has its own unique set of behaviors . the school is n't controlled by any single fish . it simply emerges if you have enough fish following the right set of local rules . it 's like an accident that happens over and over again , allowing fish all across the ocean to reliably avoid predation . and it 's not just fish . emergence is a basic property of many complex systems of interacting elements . for example , the specific way in which millions of grains of sand collide and tumble over each other almost always produces the same basic pattern of ripples . and when moisture freezes in the atmosphere , the specific binding properties of water molecules reliably produce radiating lattices that form into beautiful snowflakes . what makes emergence so complex is that you ca n't understand it by simply taking it apart , like the engine of a car . taking things apart is a good first step to understanding a complex system . but if you reduce a school of fish to individuals , it loses the ability to evade predators , and there 's nothing left to study . and if you reduce the brain to individual neurons , you 're left with something that is notoriously unreliable , and nothing like how we think and behave , at least most of the time . regardless , whatever you 're thinking about right now is n't reliant on a single neuron lodged in the corner of your brain . rather , the mind emerges from the collective activities of many , many neurons . there are billions of neurons in the human brain , and trillions of connections between all those neurons . when you turn such a complicated system like that on , it could behave in all sorts of weird ways , but it does n't . the neurons in our brain follow simple rules , just like the fish , so that as a group , their activity self-organizes into reliable patterns that let you do things like recognize faces , successfully repeat the same task over and over again , and keep all those silly little habits that everyone likes about you . so , what are the simple rules when it comes to the brain ? the basic function of each neuron in the brain is to either excite or inhibit other neurons . if you connect a few neurons together into a simple circuit , you can generate rhythmic patterns of activity , feedback loops that ramp up or shut down a signal , coincidence detectors , and disinhibition , where two inhibitory neurons can actually activate another neuron by removing inhibitory brakes . as more and more neurons are connected , increasingly complex patterns of activity emerge from the network . soon , so many neurons are interacting in so many different ways at once that the system becomes chaotic . the trajectory of the network 's activity can not be easily explained by the simple local circuits described earlier . and yet , from this chaos , patterns can emerge , and then emerge again and again in a reproducible manner . at some point , these emergent patterns of activity become sufficiently complex , and curious to begin studying their own biological origins , not to mention emergence . and what we found in emergent phenomena at vastly different scales is that same remarkable characteristic as the fish displayed : that emergence does n't require someone or something to be in charge . if the right rules are in place , and some basic conditions are met , a complex system will fall into the same habits over and over again , turning chaos into order . that 's true in the molecular pandemonium that lets your cells function , the tangled thicket of neurons that produces your thoughts and identity , your network of friends and family , all the way up to the structures and economies of our cities across the planet .
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so what does that mean ? while the school of fish is elegantly twisting , turning , and dodging sharks in what looks like deliberate coordination , each individual fish is actually just following two basic rules that have nothing to do with the shark : one , stay close , but not too close to your neighbor , and two , keep swimmming . as individuals , the fish are focused on the minutiae of these local interactions , but if enough fish join the group , something remarkable happens .
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what are the two basic ways in which neurons interact with each other ( pick two ) ? a. excitation b. inhibition c. dis-inhibition d. central pattern generator
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translator : andrea mcdonough reviewer : jessica ruby welcome to the department of plagiarism investigation . the d.p.i . has dealt with numerous complex cases in their effort to bring plagiarists to justice and to rescue purloined texts . the first form of plagiarism that the d.p.i . regularly encounters is known as brain child snatching , in honor of the latin word , plagiarius , from which plagiarism originates . brain child snatchers sneak up on innocent papers and copy and paste them without citing any sources , putting quotation marks around direct quotes or changing a word . they 've also been known to steal and hold particularly eloquent essays for ransom . when brain child snatchers get together , they form a kidnapping ring , which involves brain child snatching from multiple sources . some perpetrators have even been known to commit self-plagiarism , one of the laziest crimes in the annals of the d.p.i . also known as one-sided collaborators , these odd balls snatch up entire texts or small passages that they 've written before and present them as brand-new material . brain child snatchers and kidnapping rings are easy for the d.p.i . to catch . just paste a few passages into a search engine , and bam ! they 're caught red-handed . the more covert forms of plagiarism include the wild goose chase technique , in which plagiarists create fake authors , book titles , page numbers , or other information in order to cover up plagiarism . and the old synonym switcheroo in which plagiarists utilize a thesaurus as their main weapon . by substituting a synonym for nearly every word in the document and leaving the sentence structure and order of the ideas the same , plagiarists give legitimate paraphrasing a very bad name . shoddy paraphrasing is also a key part of variations on a smokescreen , a technique in which multiple passages are paraphrased , then pasted together into one . the thorniest issue that the d.p.i . deals with is the misconception that you can never be accused of plagiarism if you use quotes and cite your sources . this is most certainly not the case because a paper that is made up of passage upon passage of other people 's ideas is known as a wholly quotable document . this is considered plagiarism since there are no original thoughts in the work . similarly , passage after passage of too closely paraphrased text from multiple cited sources is also plagiarism of the pervasively paraphrased kind because the ideas still are n't one 's own . and lastly , the technique of revealing while concealing is plagiarism because it involves selective amnesia regarding one 's sources in an attempt to cover up wholly quotable and pervasively paraphrased issues in a text . some passages are meticulously documented , quoted , or paraphrased , while others are presented entirely as one 's own . as you can see , the d.p.i . has its hands full , tackling all sorts of academic mischief and mayhem , ranging from the petty to the outrageous . given the gravity of these transgressions , you might be wondering why you 've never heard of the department of plagiarism investigation 's victories . that 's because it does n't technically exist . but people , like you and me , can be our own d.p.i . agents to fight plagiarism and uphold the values of original thinking . we know that the best defense against plagiarism consists of writers who save themselves time , worry , and effort by taking the far easier road of just doing the work themselves .
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they 're caught red-handed . the more covert forms of plagiarism include the wild goose chase technique , in which plagiarists create fake authors , book titles , page numbers , or other information in order to cover up plagiarism . and the old synonym switcheroo in which plagiarists utilize a thesaurus as their main weapon .
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in her conspiracy theory project claiming that alien possession is the cause of plagiarism in american high schools , mary weaves together quote after quote from properly cited outside sources . has she committed plagiarism ?
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shall i ask for a show of hands or a clapping of people in different generations ? i 'm interested in how many are three to 12 years old . ( laughter ) none , huh ? ( laughter ) all right . i 'm going to talk about dinosaurs . do you remember dinosaurs when you were that age ? ( applause ) dinosaurs are kind of funny , you know . ( laughter ) we 're going to kind of go in a different direction right now . i hope you all realize that . so i 'll just give you my message up front : try not to go extinct . ( laughter ) that 's it . ( laughter ) people ask me a lot -- in fact , one of the most asked questions i get is , why do children like dinosaurs so much ? what 's the fascination ? and i usually just say , `` well , dinosaurs were big , different and gone . '' they 're all gone . well that 's not true , but we 'll get to the goose in a minute . so that 's sort of the theme : big , different and gone . the title of my talk : shape-shifting dinosaurs : the cause of a premature extinction . now i assume that we remember dinosaurs . and there 's lots of different shapes . lots of different kinds . a long time ago , back in the early 1900s , museums were out looking for dinosaurs . they went out and gathered them up . and this is an interesting story . every museum wanted a little bigger or better one than anybody else had . so if the museum in toronto went out and collected a tyrannosaur , a big one , then the museum in ottawa wanted a bigger one , and a better one . and that happened for all museums . so everyone was out looking for all these bigger and better dinosaurs . and this was in the early 1900s . by about 1970 , some scientists were sitting around and they thought , `` what in the world -- look at these dinosaurs , they 're all big . where are all the little ones ? '' ( laughter ) and they thought about it and they even wrote papers about it : `` where are the little dinosaurs ? '' ( laughter ) well , go to a museum , you 'll see , see how many baby dinosaurs there are . people assumed -- and this was actually a problem -- people assumed that if they had little dinosaurs , if they had juvenile dinosaurs , they 'd be easy to identify . you 'd have a big dinosaur and a littler dinosaur . ( laughter ) but all they had were big dinosaurs . and it comes down to a couple of things . first off , scientists have egos , and scientists like to name dinosaurs . they like to name anything . everybody likes to have their own animal that they named . ( laughter ) and so every time they found something that looked a little different , they named it something different . and what happened , of course , is we ended up with a whole bunch of different dinosaurs . in 1975 , a light went on in somebody 's head . dr. peter dodson at the university of pennsylvania actually realized that dinosaurs grew kind of like birds do , which is different than the way reptiles grow . and in fact , he used the cassowary as an example . and it 's kind of cool -- if you look at the cassowary , or any of the birds that have crests on their heads , they grow to about 80 percent adult size before the crest starts to grow . now think about that . they 're basically retaining their juvenile characteristics very late in what we call ontogeny . so allometric cranial ontogeny is relative skull growth . so you can see that if you actually found one that was 80 percent grown and you did n't know that it was going to grow up to a cassowary , you would think they were two different animals . so this was a problem , and peter dodson pointed this out using some duck-billed dinosaurs then called hypacrosaurus . and he showed that if you were to take a baby and an adult and make an average of what it should look like , if it grew in sort of a linear fashion , it would have a crest about half the size of the adult . but the actual subadult at 65 percent had no crest at all . so this was interesting . so this is where people went astray again . i mean , if they 'd have just taken that , taken peter dodson 's work , and gone on with that , then we would have a lot less dinosaurs than we have . but scientists have egos ; they like to name things . and so they went on naming dinosaurs because they were different . now we have a way of actually testing to see whether a dinosaur , or any animal , is a young one or an older one . and that 's by actually cutting into their bones . but cutting into the bones of a dinosaur is hard to do , as you can imagine , because in museums , bones are precious . you go into a museum , and they take really good care of them . they put them in foam , little containers . they 're very well taken care of . they do n't like it if you come in and want to saw them open and look inside . ( laughter ) so they do n't normally let you do that . ( laughter ) but i have a museum and i collect dinosaurs and i can saw mine open . so that 's what i do . ( applause ) so if you cut open a little dinosaur , it 's very spongy inside , like a . and if you cut into an older dinosaur , it 's very massive . you can tell it 's mature bone . so it 's real easy to tell them apart . so what i want to do is show you these . in north america in the northern plains of the united states and the southern plains of alberta and saskatchewan , there 's this unit of rock called the hell creek formation that produces the last dinosaurs that lived on earth . and there are 12 of them that everyone recognizes -- i mean the 12 primary dinosaurs that went extinct . and so we will evaluate them . and that 's sort of what i 've been doing . so my students , my staff , we 've been cutting them open . now as you can imagine , cutting open a leg bone is one thing , but when you go to a museum and say , `` you do n't mind if i cut open your dinosaur 's skull , do you ? '' they say , `` go away . '' ( laughter ) so here are 12 dinosaurs . and we want to look at these three first . so these are dinosaurs that are called pachycephalosaurus . and everybody knows that these three animals are related . and the assumption is that they 're related like cousins or whatever . but no one ever considered that they might be more closely related . in other words , people looked at them and they saw the differences . and you all know that if you are going to determine whether you 're related to your brother or your sister , you ca n't do it by looking at differences . you can only determine relatedness by looking for similarities . so people were looking at these and they were talking about how different they are . pachycephalosaurus has a big , thick dome on its head , and it 's got some little bumps on the back of its head , and it 's got a bunch of gnarly things on the end of its nose . and then stygimoloch , another dinosaur from the same age , lived at the same time , has spikes sticking out the back of its head . it 's got a little , tiny dome , and it 's got a bunch of gnarly stuff on its nose . and then there 's this thing called dracorex hogwartsia . guess where that came from ? dragon . so here 's a dinosaur that has spikes sticking out of its head , no dome and gnarly stuff on its nose . nobody noticed the gnarly stuff sort of looked alike . but they did look at these three and they said , `` these are three different dinosaurs , and dracorex is probably the most primitive of them . and the other one is more primitive than the other . '' it 's unclear to me how they actually sorted these three of them out . but if you line them up , if you just take those three skulls and just line them up , they line up like this . dracorex is the littlest one , stygimoloch is the middle-size one , pachycephalosaurus is the largest one . and one would think , that should give me a clue . ( laughter ) but it did n't give them a clue . ( laughter ) because , well we know why . scientists like to name things . so if we cut open dracorex -- i cut open our dracorex -- and look , it was spongy inside , really spongy inside . i mean , it is a juvenile and it 's growing really fast . so it is going to get bigger . if you cut open stygimoloch , it is doing the same thing . the dome , that little dome , is growing really fast . it 's inflating very fast . what 's interesting is the spike on the back of the dracorex was growing very fast as well . the spikes on the back of the stygimoloch are actually resorbing , which means they 're getting smaller as that dome is getting bigger . and if we look at pachycephalosaurus , pachycephalosaurus has a solid dome and its little bumps on the back of its head were also resorbing . so just with these three dinosaurs , as a scientist , we can easily hypothesize that it is just a growth series of the same animal . which of course means that stygimoloch and dracorex are extinct . ( laughter ) ok. ( laughter ) which of course means we have 10 primary dinosaurs to deal with . so a colleague of mine at berkeley -- he and i were looking at triceratops . and before the year 2000 -- now remember , triceratops was first found in the 1800s -- before 2000 , no one had ever seen a juvenile triceratops . there 's a triceratops in every museum in the world , but no one had ever collected a juvenile . and we know why , right ? because everybody wants to have a big one . so everyone had a big one . so we went out and collected a whole bunch of stuff and we found a whole bunch of little ones . they 're everywhere , they 're all over the place . so we have a whole bunch of them at our museum . ( laughter ) and everybody says it 's because i have a little museum . when you have a little museum , you have little dinosaurs . ( laughter ) if you look at the triceratops , you can see it 's changing , it 's shape-shifting . as the juveniles are growing up , their horns actually curve backwards . and then as they get older , the horns grow forward . and that 's pretty cool . if you look along the edge of the frill , they have these little triangular bones that actually grow big as triangles and then they flatten against the frill pretty much like the spikes do on the pachycephalosaurs . and then , because the juveniles are in my collection , i cut them open ... ( laughter ) and look inside . and the little one is really spongy . and the middle-size one is really spongy . but what was interesting was the adult triceratops was also spongy . and this is a skull that is two meters long . it 's a big skull . but there 's another dinosaur that is found in this formation that looks like a triceratops , except it 's bigger , and it 's called torosaurus . and torosaurus , when we cut into it , has mature bone . but it 's got these big holes in its shield . and everybody says , `` a triceratops and a torosaurus ca n't possibly be the same animal because one of them 's bigger than the other one . '' ( laughter ) `` and it has holes in its frill . '' and i said , `` well do we have any juvenile torosauruses ? '' and they said , `` well , no , but it has holes in its frill . '' so one of my graduate students , john scannella , looked through our whole collection and he actually discovered that the hole starting to form in triceratops and , of course it 's open , in torosaurus -- so he found the transitional ones between triceratops and torosaurus , which was pretty cool . so now we know that torosaurus is actually a grown-up triceratops . now when we name dinosaurs , when we name anything , the original name gets to stick and the second name is thrown out . so torosaurus is extinct . triceratops , if you 've heard the news , a lot of the newscasters got it all wrong . they thought torosaurus should be kept and triceratops thrown out , but that 's not going to happen . ( laughter ) all right , so we can do this with a bunch of dinosaurs . i mean , here 's edmontosaurus and anatotitan . anatotitan : giant duck . it 's a giant duck-bill dinosaur . here 's another one . so we look at the bone histology . the bone histology tells us that edmontosaurus is a juvenile , or at least a subadult , and the other one is an adult , and we have an ontogeny . and we get rid of anatotitan . so we can just keep doing this . and the last one is t. rex . so there 's these two dinosaurs , t. rex and nanotyrannus . ( laughter ) again , it makes you wonder . ( laughter ) but they had a good question . they were looking at them and they said , `` one 's got 17 teeth , and the biggest one 's got 12 teeth . and that does n't make any sense at all , because we do n't know of any dinosaurs that gain teeth as they get older . so it must be true -- they must be different . '' so we cut into them . and sure enough , nanotyrannus has juvenile bone and the bigger one has more mature bone . it looks like it could still get bigger . and at the museum of the rockies where we work , i have four t. rexes , so i can cut a whole bunch of them . but i did n't have to cut any of them really , because i just lined up their jaws and it turned out the biggest one had 12 teeth and the next smallest one had 13 and the next smallest had 14 . and of course , nano has 17 . and we just went out and looked at other people 's collections and we found one that has sort of 15 teeth . so again , real easy to say that tyrannosaurus ontogeny included nanotyrannus , and therefore we can take out another dinosaur . ( laughter ) so when it comes down to our end cretaceous , we have seven left . and that 's a good number . that 's a good number to go extinct , i think . now as you can imagine , this is not very popular with fourth-graders . ( laughter ) fourth-graders love their dinosaurs , they memorize them . and they 're not happy with this . ( laughter ) thank you very much . ( applause )
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and it comes down to a couple of things . first off , scientists have egos , and scientists like to name dinosaurs . they like to name anything .
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how can scientists tell if a dinosaur is old or young ?
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every day we are bombarded on all platforms of media with personal stories that span the continuum from the embarrassing and the trivial to the dire and the critical . the foodie posting photos of every plate of lasagna he orders , the iranian blogger describing the shooting death of nedā āghā-soltān . authentic narrative is the glue that connects people , providing a compelling reason to keep reading . it makes the personal universal , transcends the individual , and makes a story timeless and humanistic . how , as a journalist , do you ask the questions that yield this type of narrative ? you have to know what to ask of whom . first you need to understand that every piece of journalism requires a trifecta of sourcing . if you picture the reporting process as depicted by a triangle , one side will be official sources , another side will be overview sources , and a third side will be unofficial sources . all three components are necessary in every well-reported piece . the first side has official sources . those are the people with titles and expertise , who own the company ; are spokespeople for the movement . they tell you the numbers , and the answers to how much , how many , where , when , and who . a second side of the triangle includes overview sources : academics , consultants , authors , who are not directly connected as stakeholders , but have knowledge of the big picture . yet it is the third side of the trifecta - unofficial sources - who hold the power of the individual 's insight . this is where you can find the why , giving consequence on the event , trend , phase , or idea and what it means on a soul level to someone affected by it . so how do you mine for the gems , identifying what is compelling from what is chatter ? you ask surprising questions . to achieve the complicated , fragile human connection , you regard the stories of every subject as sacred . realize that an anecdote is oxygen that breathes life into a grey story of exposition , facts and data . what the surgeon did at home the morning he operated on a woman 's brain tumor . how it feels to dream and train for the olympics for a lifetime . there are times when it is important to convey information quickly , to present bulleted facts and updates . when a situation is urgent , when action is required now , when you need to know where the tornado will hit , how fast the fire is spreading , and if it will reach your home today . but the narrative personal stories that contribute to the buffet of journalism are pieces that have the luxury of a slow dance of information . it is this artful solicitation of story that will make the journalism memorable and will deliver the narrative bond that will connect us to each other .
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when a situation is urgent , when action is required now , when you need to know where the tornado will hit , how fast the fire is spreading , and if it will reach your home today . but the narrative personal stories that contribute to the buffet of journalism are pieces that have the luxury of a slow dance of information . it is this artful solicitation of story that will make the journalism memorable and will deliver the narrative bond that will connect us to each other .
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what elements help an interviewer mine for personal information from a subject ?
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when you think about the brain , it 's difficult to understand , because if i were to ask you right now , how does the heart work , you would instantly tell me it 's a pump . it pumps blood . if i were to ask about your lungs , you would say it exchanges oxygen for carbon dioxide . that 's easy . if i were to ask you how the brain works , it 's hard to understand because you ca n't just look at a brain and understand what it is . it 's not a mechanical object , not a pump , not an airbag . it 's just like , if you held it in your hand when it was dead , it 's just a piece of fat . to understand how the brain works , you have to go inside a living brain . because the brain 's not mechanical , the brain is electrical and it 's chemical . your brain is made out of 100 billion cells , called neurons . and these neurons communicate with each other with electricity . and we 're going to eavesdrop in on a conversation between two cells , and we 're going to listen to something called a spike . but we 're not going to record my brain or your brain or your teachers ' brains , we 're going to use our good friend the cockroach . not just because i think they 're cool , but because they have brains very similar to ours . so if you learn a little bit about how their brains work , we 're going to learn a lot about how our brains work . i 'm going to put them in some ice water here and then -- audience : ew ! greg gabe : yeah ... right now they 're becoming anesthetized . because they 're cold blooded , they become the temperature of the water and they ca n't control it so they just basically `` chillax , '' right ? they 're not going to feel anything , which may tell you a little about what we 're going to do , a scientific experiment to understand the brain . so ... this is the leg of a cockroach . and a cockroach has all these beautiful hairs and pricklies all over it . underneath each one of those is a cell , and this cell 's a neuron that is going to send information about wind or vibration . if you ever try to catch a cockroach , it 's hard because they can feel you coming before you 're even there , they start running . these cells are zipping up this information up to the brain using those little axons with electronic messages in there . we 're going to record by sticking a pin right in there . we need to take off the leg of a cockroach -- do n't worry , they 'll grow back -- then we 're going to put two pins in there . these are metal pins . one will pick up this electronic message , this electric message is going by . so , we 're now going to do the surgery , let 's see if you guys can see this . yeah , it 's gross ... all right . so there we go . you guys can see his leg right there . now i 'm going to take this leg , i 'm going to put it in this invention that we came up with called the spikerbox -- and this replaces lots of expensive equipment in a research lab , so you guys can do this in your own high schools , or in your own basements if it 's me . ( audience : laughter ) so , there . can you guys see that ? alright , so i 'm going to go ahead and turn this on . i 'm going to plug it in . ( tuning sound ) to me , this is the most beautiful sound in the world . this is what your brain is doing right now . you have 100 billion cells making these raindrop-type noises . let 's take a look at what it looks like , let 's pull it up on the ipad screen . i plugged my ipad into here as well . so remember we said the axon looks like a spike . so we 're going to take a look at what one of them looks like in just a brief second . we 're going to tap here , so we can sort of average this guy . so there we see it . that 's an action potential . you 've got 100 billion cells in your brain doing this right now , sending all this information back about what you 're seeing , hearing . we also said this is a cell that 's going to be taking up information about vibrations in the wind . so what if we do an experiment ? we can actually blow on this and hear if we see a change . are you guys going to be ready ? if i blow on it you tell me if you hear anything . ( blowing ) ( sound changes ) let me just touch this with a little pen here . ( noise ) that was the neural firing rate . that actually took a while in neuroscience to understand this . this is called rate coding : the harder you press on something , the more spikes there are , and all that information is coming up to your brain . that 's how you perceive things . so that 's one way of doing an experiment with electricity . the other way is that your brain is not only taking in electrical impulses , you 're also sending out . that 's how you move your muscles around . let 's see what happens if i 've plugged in something that 's electric into the cockroach leg here . i 'm going to take two pins , i 'm going to plug them onto the cockroach . i 'm going to take the other end , i 'm going to plug in into my ipod . it 's my iphone actually . do you guys know how your earbuds work in your ears ? you have a battery in your phone , or ipod , right ? it 's sending electrical current into these magnets in your earbuds which shake back and forth and allow you to hear things . but that current 's the same currency that our brain uses , so we can send that to our cockroach leg and hopefully if this works , we can actually see what happens when we play music into the cockroach . let 's take a look . ( music beat ) can we turn it up ? there we go . ( audience reacts and gasps ) gg : so what 's happening ? audience : wow ! ( laughter ) so you see what 's moving . it 's moving on the bass . all those audiophiles out there , if you have awesome , kicking car stereos , you know , the bass speakers are the biggest speakers . the biggest speakers have the longest waves , which have the most current , and the current is what 's causing these things to move . so it 's not just speakers that are causing electricity . microphones also cause electricity . ( beat ) so i 'm going to go ahead and invite another person out on the stage here to help me out with this . so there we go . ( beatboxing ) this is the first time this has ever happened in the history of mankind . human beatbox to a cockroach leg . when you guys go back to your high school , think about neuroscience and how you guys can begin the neuro-revolution . thank you very much . bye bye . ( applause )
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i 'm going to take the other end , i 'm going to plug in into my ipod . it 's my iphone actually . do you guys know how your earbuds work in your ears ?
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how did gage use his iphone during his experiment ?
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meet the nurdles . they may be tiny , look harmless , and sound like a bunch of cartoon characters , but do n't be fooled . these little guys are plotting ocean domination . nurdles are some of the planet 's most pervasive pollutants , found in lakes , rivers , and oceans across the globe . the tiny factory-made pellets form the raw material for every plastic product we use . and each year , billions of pounds of nurdles are produced , melted , and molded into toys , bottles , buttons , bags , pens , shoes , toothbrushes , and beads . they are everywhere . and they come in many guises , multi-colored and many-shaped , they range in size from just a few millimeters to mere specks that are only visible through a microscope . but their real advantage in the quest for ocean domination is their incredible endurance , which allows them to persist in an environment for generations because their artificial makeup makes them unable to biodegrade . so , just as long as they do n't get into the environment , we have nothing to worry about , right ? the problem is nurdles have a crafty way of doing exactly this . produced in several countries and shipped to plastic manufacturing plants the world over , nurdles often escape during the production process , carried by runoff to the coast or during shipping when they 're mistakenly tipped into the waves . once in the water , nurdles are swiftly carried by currents , ultimately winding up in huge circulating ocean systems called gyres , where they convene to plan their tactics . the earth has five gyres that act as gathering points , but the headquarters of nurdle ocean domination are in the pacific ocean , where the comparative enormity of the gyre and the resulting concentration of pollution is so huge that it 's known as the great pacific garbage patch . here , nurdles have good company . this gyre draws in all kinds of pollution , but because they do n't biodegrade , plastics dominate , and they come from other sources besides nurdles , too . you know those tiny beads you see in your face wash or your toothpaste ? they 're often made of plastic , and after you flush them down the drain , some also end up in this giant garbage patch , much to the delight of the nurdles , building up their plastic army there . and then there are the large pieces of unrecycled plastic litter , like bottles and carrier bags , transported by runoff from land to sea . over time , these plastic chunks turn into a kind of nurdle , too , but one that 's been worn down by the elements , not made in a factory . and as if they were n't threatening enough , the rough , pitted surfaces of these microplastics , the name we give to all those collective plastic bits , water-born chemicals stick , or adhere , to them , making them toxic . this gathering has grown so immense that the oceanic garbage patch can shift from around the size of texas to something the size of the united states . but while this toxic tornado is circulating , the birds , fish , filter feeders , whales , and crustaceans around it are just going about their daily business , which means they 're looking for food . unfortunately for them , tiny bits of floating plastic look a lot like fish eggs and other enticing bits of food . but once ingested , microplastics have a very different and terrible habit of sticking around . inside an animal 's stomach , they not only damage its health with a cocktail of toxins they carry but can also lead to starvation because although nurdles may be ingested , they 're never digested , tricking an animal into feeling like it 's continually full and leading to its eventual death . when one organism consumes another , microplastics and their toxins are then passed up through the food chain . and that 's how , bit by bit , nurdles accomplish their goal , growing ever more pervasive as they wipe out marine life and reshape the ocean 's ecosystems . so , how to break this cycle ? the best solution would be to take plastics out of the equation altogether . that 'll take a lot of time but requires only small collective changes , like more recycling , replacing plastics with paper and glass , and ditching that toothpaste with the microbeads . if we accomplish these things , perhaps over time fewer and fewer nurdles will turn up at that giant garbage patch , their army of plastics will grow weaker , and they 'll surrender the ocean to its true keepers once more .
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so , how to break this cycle ? the best solution would be to take plastics out of the equation altogether . that 'll take a lot of time but requires only small collective changes , like more recycling , replacing plastics with paper and glass , and ditching that toothpaste with the microbeads .
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commonly , the best answer to removing plastics from the ocean is to reduce , reuse or recycle . give specific examples ( one for each of the 3 r ’ s ) of what you could change in your own life to help reduce plastics .
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back in new york , i am the head of development for a non-profit called robin hood . when i 'm not fighting poverty , i 'm fighting fires as the assistant captain of a volunteer fire company . now in our town , where the volunteers supplement a highly skilled career staff , you have to get to the fire scene pretty early to get in on any action . i remember my first fire . i was the second volunteer on the scene , so there was a pretty good chance i was going to get in . but still it was a real footrace against the other volunteers to get to the captain in charge to find out what our assignments would be . when i found the captain , he was having a very engaging conversation with the homeowner , who was surely having one of the worst days of her life . here it was , the middle of the night , she was standing outside in the pouring rain , under an umbrella , in her pajamas , barefoot , while her house was in flames . the other volunteer who had arrived just before me -- let 's call him lex luther -- ( laughter ) got to the captain first and was asked to go inside and save the homeowner 's dog . the dog ! i was stunned with jealousy . here was some lawyer or money manager who , for the rest of his life , gets to tell people that he went into a burning building to save a living creature , just because he beat me by five seconds . well , i was next . the captain waved me over . he said , `` bezos , i need you to go into the house . i need you to go upstairs , past the fire , and i need you to get this woman a pair of shoes . '' ( laughter ) i swear . so , not exactly what i was hoping for , but off i went -- up the stairs , down the hall , past the 'real ' firefighters , who were pretty much done putting out the fire at this point , into the master bedroom to get a pair of shoes . now i know what you 're thinking , but i 'm no hero . ( laughter ) i carried my payload back downstairs where i met my nemesis and the precious dog by the front door . we took our treasures outside to the homeowner , where , not surprisingly , his received much more attention than did mine . a few weeks later , the department received a letter from the homeowner thanking us for the valiant effort displayed in saving her home . the act of kindness she noted above all others : someone had even gotten her a pair of shoes . ( laughter ) in both my vocation at robin hood and my avocation as a volunteer firefighter , i am witness to acts of generosity and kindness on a monumental scale , but i 'm also witness to acts of grace and courage on an individual basis . and you know what i 've learned ? they all matter . so as i look around this room at people who either have achieved , or are on their way to achieving , remarkable levels of success , i would offer this reminder : do n't wait . do n't wait until you make your first million to make a difference in somebody 's life . if you have something to give , give it now . serve food at a soup kitchen . clean up a neighborhood park . be a mentor . not every day is going to offer us a chance to save somebody 's life , but every day offers us an opportunity to affect one . so get in the game . save the shoes . thank you . ( applause ) bruno giussani : mark , mark , come back . ( applause ) mark bezos : thank you .
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so , not exactly what i was hoping for , but off i went -- up the stairs , down the hall , past the 'real ' firefighters , who were pretty much done putting out the fire at this point , into the master bedroom to get a pair of shoes . now i know what you 're thinking , but i 'm no hero . ( laughter ) i carried my payload back downstairs where i met my nemesis and the precious dog by the front door .
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do you consider yourself a hero ? if so , explain how you exhibit the qualities of a hero . if not , what can you change in order to incorporate more hero like traits into your character ?
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a toothpaste brand claims their product will destroy more plaque than any product ever made . a politician tells you their plan will create the most jobs . we 're so used to hearing these kinds of exaggerations in advertising and politics that we might not even bat an eye . but what about when the claim is accompanied by a graph ? afterall , a graph is n't an opinion . it represents cold , hard numbers , and who can argue with those ? yet , as it turns out , there are plenty of ways graphs can mislead and outright manipulate . here are some things to look out for . in this 1992 ad , chevy claimed to make the most reliable trucks in america using this graph . not only does it show that 98 % of all chevy trucks sold in the last ten years are still on the road , but it looks like they 're twice as dependable as toyota trucks . that is , until you take a closer look at the numbers on the left and see that the figure for toyota is about 96.5 % . the scale only goes between 95 and 100 % . if it went from 0 to 100 , it would look like this . this is one of the most common ways graphs misrepresent data , by distorting the scale . zooming in on a small portion of the y-axis exaggerates a barely detectable difference between the things being compared . and it 's especially misleading with bar graphs since we assume the difference in the size of the bars is proportional to the values . but the scale can also be distorted along the x-axis , usually in line graphs showing something changing over time . this chart showing the rise in american unemployment from 2008 to 2010 manipulates the x-axis in two ways . first of all , the scale is inconsistent , compressing the 15-month span after march 2009 to look shorter than the preceding six months . using more consistent data points gives a different picture with job losses tapering off by the end of 2009 . and if you wonder why they were increasing in the first place , the timeline starts immediately after the u.s. 's biggest financial collapse since the great depression . these techniques are known as cherry picking . a time range can be carefully chosen to exclude the impact of a major event right outside it . and picking specific data points can hide important changes in between . even when there 's nothing wrong with the graph itself , leaving out relevant data can give a misleading impression . this chart of how many people watch the super bowl each year makes it look like the event 's popularity is exploding . but it 's not accounting for population growth . the ratings have actually held steady because while the number of football fans has increased , their share of overall viewership has not . finally , a graph ca n't tell you much if you do n't know the full significance of what 's being presented . both of the following graphs use the same ocean temperature data from the national centers for environmental information . so why do they seem to give opposite impressions ? the first graph plots the average annual ocean temperature from 1880 to 2016 , making the change look insignificant . but in fact , a rise of even half a degree celsius can cause massive ecological disruption . this is why the second graph , which show the average temperature variation each year , is far more significant . when they 're used well , graphs can help us intuitively grasp complex data . but as visual software has enabled more usage of graphs throughout all media , it 's also made them easier to use in a careless or dishonest way . so the next time you see a graph , do n't be swayed by the lines and curves . look at the labels , the numbers , the scale , and the context , and ask what story the picture is trying to tell .
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and if you wonder why they were increasing in the first place , the timeline starts immediately after the u.s. 's biggest financial collapse since the great depression . these techniques are known as cherry picking . a time range can be carefully chosen to exclude the impact of a major event right outside it .
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which of the following is an example of “ cherry picking ” data ?
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translator : andrea mcdonough reviewer : jessica ruby today , we 're going to look at the world of rome through the eyes of a young girl . here she is , drawing a picture of herself in the atrium of her father 's enormous house . her name is domitia , and she is just 5 years old . she has an older brother who is fourteen , lucius domitius ahenobarbus , named after her dad . girls do n't get these long names that boys have . what is worse is that dad insists on calling all his daughters domitia . `` domitia ! '' his call to domitia drawing on the column , domitia iii . she has an older sister , domitia ii , who is 7 years old . and then there 's domitia i , who is ten . there would have been a domitia iv , but mom died trying to give birth to her three years ago . confused ? the romans were too . they could work out ancestry through the male line with the nice , tripartite names such as lucius domitius ahenobarbus . but they got in a real mess over which domitia was married to whom and was either the great aunt or the great stepmother and so on to whom when they came to write it down . domitia iii is not just drawing on the pillar , she 's also watching the action . you see , it 's early , in the time of day when all her dad 's clients and friends come to see him at home to pay their respects . lucius popidius secundus , a 17 year old , he wants to marry domitia ii within the next five to seven years , has come as well . he seems to be wooing not his future wife , but her dad . poor lucius , he does not know that domitia 's dad thinks he and his family are wealthy but still scumbags from the subura . afterall , it is the part of rome full of barbers and prostitutes . suddenly , all the men are leaving with dad . it 's the second hour and time for him to be in court with a sturdy audience of clients to applaud his rhetoric and hiss at his opponent . the house is now quieter . the men wo n't return for seven hours , not until dinner time . but what happens in the house for those seven hours ? what do domitia , domitia , and domitia do all day ? not an easy question ! everything written down by the romans that we have today was written by men . this makes constructing the lives of women difficult . however , we ca n't have a history of just roman men , so here it goes . we can begin in the atrium . there is a massive loom , on which dad 's latest wife is working on a new toga . domitia , domitia , and domitia are tasked with spinning the wool that will be used to weave this mighty garment , 30 or more feet long and elliptical in shape . romans loved the idea that their wives work wool . we know that because it 's written on the gravestones of so many roman women . unlike women in greece , roman women go out the house and move about the city . they go to the baths in the morning to avoid the men or to separate baths that are for women only . some do go in for the latest fad of the ad 70s : nude bathing with men present . where they have no place is where the men are : in the forum , in the law court , or in the senate house . their place in public is in the porticos with gardens , with sculpture , and with pathways for walking in . when domitia , domitia , and domitia want to leave the house to go somewhere , like the portico of livia , they must get ready . domitia ii and domitia iii are ready , but domitia i , who is betrothed to be married in two years to darling philatus , is n't ready . she 's not slow , she just has more to do . being betrothed means she wears the insignia of betrothal : engagement rings and all the gifts pilatus has given her - jewels , earrings , necklaces , and the pendants . she may even wear her myrtle crown . all this bling shouts , `` i 'm getting married to that 19 year old who gave me all this stuff i 'm wearing ! '' while as they wait , domitia ii and domitia iii play with their dolls that mirror the image of their sister decked out to be married . one day , these dolls will be dedicated to the household gods on the day of their wedding . okay , we 're ready . the girls step into litters carried by some burly slaves . they also have a chaperone with them and will be meeting an aunt at the porticus of livia . carried high on the shoulders of these slaves , the girls look out through the curtains to see the crowded streets below them . they traverse the city , pass the coliseum , but then turn off to climb up the hill to the porticus of livia . it was built by livia , the wife of the first emperor augustus , on the site of the house of vedius pollio . he was n't such a great guy . he once tried to feed a slave to the eels in his fish pond for simply dropping a dish . luckily , the emperor was at the dinner and tamed his temper . the litters are placed on the ground and the girls get out and arm in arm , two by two , they ascend the steps into the enclosed garden with many columns . domitia iii shot off and is drawing on a column . domitia ii joins her but seeks to read the graffiti higher up on the column . she spots a drawing of gladiators and tries to imagine seeing them fighting , something she will never be permitted to do , except from the very rear of the coliseum . from there , she will have a good view of the 50,000 spectators but will see little by way of blood and gore . if she really wanted a decent view , she could become a vestal virgin and would sit right down the front . but a career tending the sacred flame of vesta is not to everybody 's taste . domitia i has met another ten year old also decked out in the insignia of betrothal . home time . when they get there after the eighth hour , something is up . a smashed dish lies on the floor . all the slaves are being gathered together in the atrium and await the arrival of their master . dad is going to go mad . he will not hit his children , but like many other romans , he believes that slaves have to be punished . the whip lies ready for his arrival . no one knows who smashed the dish , but dad will call the undertaker to torture it out of them , if he must . the doorkeeper opens the front door to the house . a hush comes over the anxious slaves . in walks not their master but , instead , a pregnant teenager . it is the master 's eldest daughter , age 15 , who is already a veteran of marriage and child birth . guess what her name is . there is a five to ten percent chance she wo n't survive giving birth to her child , but , for now , she has come to dinner with her family . as a teenage mother , she has proved that she is a successful wife by bringing children and descendants for her husband , who will carry on his name in the future . the family head off to the dining room and are served dinner . it would seem dad has had an invite to dinner elsewhere . with dinner concluded , the girls crossed the atrium to bid farewell to their older sister who is carried home in a litter , escorted by some of dad 's bodyguards . returning to the house , the girls cross the atrium . the slaves , young and old , male and female , await the return of their owner . when he returns , he may exact vengeance , ensuring his power over the slaves is maintained through violence and terror , to which any slave could be subjected . but , for the girls , they head upstairs for the night , ready for bed .
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unlike women in greece , roman women go out the house and move about the city . they go to the baths in the morning to avoid the men or to separate baths that are for women only . some do go in for the latest fad of the ad 70s : nude bathing with men present . where they have no place is where the men are : in the forum , in the law court , or in the senate house .
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where do the men go at the second hour ?
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imagine setting sail from hawaii in a canoe . your target is a small island thousands of kilometers away in the middle of the pacific ocean . that 's a body of water that covers more than 160 million square kilometers , greater than all the landmasses on earth combined . for thousands of years , polynesian navigators managed voyages like this without the help of modern navigational aids . ancient polynesians used the sun , moon , stars , planets , ocean currents , and clouds as guides that allowed them to see the ocean as a series of pathways rather than an obstacle . their voyages began around 1500 b.c . when the people who would settle polynesia first set sail from southeast asia . early polynesians eventually settled a vast area of islands spread over 40 million square kilometers of the pacific ocean . some historians believe the voyagers moved from place to place to avoid overpopulation . others , that they were driven by war . voyages became less frequent by around 1300 a.d. as polynesian societies became more rooted in specific locations . during the voyaging period , successful journeys depended on a number of factors : well-built canoes , the skill of navigators , and weather being some of the biggest . voyages relied on sturdy wa'a kaulua , or double-hulled canoes , which were powered by sails and steered with a single large oar . canoe building involved the whole community , bringing together the navigators , canoe builders , priests , chanters , and hula dancers . navigators were keen observers of the natural world . they were abundantly familiar with trade wind-generated ocean swells , which typically flow northeast or southeast . by day , navigators could identify direction by the rocking motion of their canoes caused by these swells . but sunrise and sunset were even more useful . the sun 's position indicated east and west and created low light on the ocean that made it possible to see swells directly . at night , navigators used something called a star compass , which was n't a physical object , but rather a sort of mental map . they memorized the rising and setting points of stars and constellations at different times of the year . they used those to divide the sky into four quadrants , subdivided into 32 houses , with the canoe in the middle . so , for example , when they saw the star pira ‘ atea rising from the ocean , they knew that to be northeast . they had some other tricks , too . the earth 's axis points towards hokupa'a , or the north star , so called because it 's the one fixed point in the sky as the earth rotates and always indicates north . however , it 's not visible south of the equator , so navigators there could use a constellation called newe , or the southern cross , and some mental tricks to estimate where south is . for instance , draw a line through these two stars , extend it 4.5 times , and draw another line from there to the horizon . that 's south . but the sky also contains navigational aids much closer to earth , the clouds . besides being useful weather cues , under the right conditions , they can indicate landmasses . for instance , the lagoons of pacific atolls can actually be seen reflected on the underside of clouds , if you know what to look for . and high masses of clouds can indicate mountainous islands . once navigators neared their destination , other clues , such as the flight patterns of birds , floating debris or vegetation , and types of fish in the area helped determine the proximity of land . for example , the manu-o-ku had a known flight range of 190 kilometers , and could be followed back to shore . so how do we know all of this ? partially through evidence in petroglyphs , written observations of european explorers , and polynesian oral traditions . but also by trying them out for ourselves . in 2017 , a voyaging canoe called hokulea completed a worldwide voyage using only these techniques . if that seems remarkable , remember the ancient polynesians , who through close study and kinship with nature , were able to forge these paths across an unfathomably vast , vibrant living ocean .
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early polynesians eventually settled a vast area of islands spread over 40 million square kilometers of the pacific ocean . some historians believe the voyagers moved from place to place to avoid overpopulation . others , that they were driven by war .
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early polynesian voyages took place from approximately :
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`` sorry , my phone died . '' `` it 's nothing . i 'm fine . '' `` these allegations are completely unfounded . '' `` the company was not aware of any wrongdoing . '' `` i love you . '' we hear anywhere from 10 to 200 lies a day , and we spent much of our history coming up with ways to detect them , from medieval torture devices to polygraphs , blood-pressure and breathing monitors , voice-stress analyzers , eye trackers , infrared brain scanners , and even the 400-pound electroencephalogram . but although such tools have worked under certain circumstances , most can be fooled with enough preparation , and none are considered reliable enough to even be admissible in court . but , what if the problem is not with the techniques , but the underlying assumption that lying spurs physiological changes ? what if we took a more direct approach , using communication science to analyze the lies themselves ? on a psychological level , we lie partly to paint a better picture of ourselves , connecting our fantasies to the person we wish we were rather than the person we are . but while our brain is busy dreaming , it 's letting plenty of signals slip by . our conscious mind only controls about 5 % of our cognitive function , including communication , while the other 95 % occurs beyond our awareness , and according to the literature on reality monitoring , stories based on imagined experiences are qualitatively different from those based on real experiences . this suggests that creating a false story about a personal topic takes work and results in a different pattern of language use . a technology known as linguistic text analysis has helped to identify four such common patterns in the subconscious language of deception . first , liars reference themselves less , when making deceptive statements . they write or talk more about others , often using the third person to distance and disassociate themselves from their lie , which sounds more false : `` absolutely no party took place at this house , '' or `` i did n't host a party here . '' second , liars tend to be more negative , because on a subconscious level , they feel guilty about lying . for example , a liar might say something like , `` sorry , my stupid phone battery died . i hate that thing . '' third , liars typically explain events in simple terms since our brains struggle to build a complex lie . judgment and evaluation are complex things for our brains to compute . as a u.s. president once famously insisted : `` i did not have sexual relations with that woman . '' and finally , even though liars keep descriptions simple , they tend to use longer and more convoluted sentence structure , inserting unnecessary words and irrelevant but factual sounding details in order to pad the lie . another president confronted with a scandal proclaimed : `` i can say , categorically , that this investigation indicates that no one on the white house staff , no one in this administration presently employed was involved in this very bizarre incident . '' let 's apply linguistic analysis to some famous examples . take seven-time tour de france winner lance armstrong . when comparing a 2005 interview , in which he had denied taking performance-enhancing drugs to a 2013 interview , in which he admitted it , his use of personal pronouns increased by nearly 3/4 . note the contrast between the following two quotes . first : `` okay , you know , a guy in a french , in a parisian laboratory opens up your sample , you know , jean-francis so-and-so , and he tests it . and then you get a phone call from a newspaper that says : 'we found you to be positive six times for epo . '' second : `` i lost myself in all of that . i 'm sure there would be other people that could n't handle it , but i certainly could n't handle it , and i was used to controlling everything in my life . i controlled every outcome in my life . '' in his denial , armstrong described a hypothetical situation focused on someone else , removing himself from the situation entirely . in his admission , he owns his statements , delving into his personal emotions and motivations . but the use of personal pronouns is just one indicator of deception . let 's look at another example from former senator and u.s. presidential candidate john edwards : `` i only know that the apparent father has said publicly that he is the father of the baby . i also have not been engaged in any activity of any description that requested , agreed to , or supported payments of any kind to the woman or to the apparent father of the baby . '' not only is that a pretty long-winded way to say , `` the baby is n't mine , '' but edwards never calls the other parties by name , instead saying `` that baby , '' `` the woman , '' and `` the apparent father . '' now let 's see what he had to say when later admitting paternity : `` i am quinn 's father . i will do everything in my power to provide her with the love and support she deserves . '' the statement is short and direct , calling the child by name and addressing his role in her life . so how can you apply these lie-spotting techniques to your life ? first , remember that many of the lies we encounter on a daily basis are far less serious that these examples , and may even be harmless . but it 's still worthwhile to be aware of telltale clues , like minimal self-references , negative language , simple explanations and convoluted phrasing . it just might help you avoid an overvalued stock , an ineffective product , or even a terrible relationship .
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i hate that thing . '' third , liars typically explain events in simple terms since our brains struggle to build a complex lie . judgment and evaluation are complex things for our brains to compute .
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do liars tell simple or more detailed and action-based accounts of events ?
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many generations have felt they 've reached the pinnacle of technological advancement , yet look back 100 years , and the technologies we take for granted today would seem like impossible magic . so will there be a point where we reach an actual limit of technological progress ? and if so , are we anywhere near that limit now ? half a century ago , russian astronomer nikolai kardashev was asking similar questions when he came up with a way to measure technological progress , even when we have no idea exactly what it might look like . anything we do in the future will require energy , so kardashev 's scale classifies potential civilizations , whether alien civilizations out there in the universe or our own , into three levels based on energy consumption . the tiny amount of energy we currently consume pales next to what we leave untapped . a type i , or planetary civilization , can access all the energy resources of its home planet . in our case , this is the 174,000 terawatts earth receives from the sun . we currently only harness about 15 terawatts of it , mostly by burning solar energy stored in fossil fuels . to approach becoming a type i civilization , we would need to capture solar energy more directly and efficiently by covering the planet with solar panels . based on the most optimistic models , we might get there within just four centuries . what would be next ? well , the earth only gets a sliver of the sun 's energy , while the rest of its 400 yottawatts is wasted in dead space . but a type ii , or stellar civilization , would make the most of its home star 's energy . instead of installing solar panels around a planet , a type ii civilization would install them directly orbiting its star , forming a theoretical structure called a dyson sphere . and the third step ? a type iii civilization would harness all the energy of its home galaxy . but we can also think of progress in the opposite way . how small can we go ? to that end , british cosmologist john barrow classified civilizations by the size of objects they control . that ranges from mechanical structures at our own scale , to the building blocks of our own biology , down to unlocking atoms themselves . we 've currently touched the atomic level , though our control remains limited . but we potentially could go much smaller in the future . to get a sense of the extent to which that 's true , the observable universe is 26 orders of magnitude larger than a human body . that means if you zoomed out by a factor of ten 26 times , you 'd be at the scale of the universe . but to reach the minimum length scale , known as the planck length , you would need to zoom in 35 times . as physicist richard feynman once said , `` there 's plenty of room at the bottom . '' instead of one or the other , it 's likely that our civilization will continue to develop along both kardashev and barrow scales . precision on a smaller scale lets us use energy more efficiently and unlocks new energy sources , like nuclear fusion , or even antimatter . and this increased energy lets us expand and build on a larger scale . a truly advanced civilization , then , would harness both stellar energy and subatomic technologies . but these predictions were n't made just for us humans . they double as a possible means of detecting intelligent life in the universe . if we find a dyson sphere around a distant star , that 's a pretty compelling sign of life . or , what if , instead of a structure that passively soaked up all the star 's energy , like a plant , an alien civilization built one that actively sucked the energy out of the star like a hummingbird . frighteningly enough , we 've observed super dense celestial bodies about the size of a planet that drain energy out of a much bigger star . it would be much too premature to conclude that this is evidence of life in the universe . there are also explanations for these observations that do n't involve alien life forms . but that does n't stop us from asking , `` what if ? ''
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that means if you zoomed out by a factor of ten 26 times , you 'd be at the scale of the universe . but to reach the minimum length scale , known as the planck length , you would need to zoom in 35 times . as physicist richard feynman once said , `` there 's plenty of room at the bottom . ''
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from the human scale , how many times do we need to zoom in to reach the minimum scale ?
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i 'm here because i have a very important message : i think we have found the most important factor for success . and it was found close to here , stanford . psychology professor took kids that were four years old and put them in a room all by themselves . and he would tell the child , a four-year-old kid , `` johnny , i am going to leave you here with a marshmallow for 15 minutes . if , after i come back , this marshmallow is here , you will get another one . so you will have two . '' to tell a four-year-old kid to wait 15 minutes for something that they like , is equivalent to telling us , `` we 'll bring you coffee in two hours . '' ( laughter ) exact equivalent . so what happened when the professor left the room ? as soon as the door closed ... two out of three ate the marshmallow . five seconds , 10 seconds , 40 seconds , 50 seconds , two minutes , four minutes , eight minutes . some lasted 14-and-a-half minutes . ( laughter ) could n't do it . could not wait . what 's interesting is that one out of three would look at the marshmallow and go like this ... would look at it . put it back . they would walk around . they would play with their skirts and pants . that child already , at four , understood the most important principle for success , which is the ability to delay gratification . self-discipline : the most important factor for success . 15 years later , 14 or 15 years later , follow-up study . what did they find ? they went to look for these kids who were now 18 and 19 . and they found that 100 percent of the children that had not eaten the marshmallow were successful . they had good grades . they were doing wonderful . they were happy . they had their plans . they had good relationships with the teachers , students . they were doing fine . a great percentage of the kids that ate the marshmallow , they were in trouble . they did not make it to university . they had bad grades . some of them dropped out . a few were still there with bad grades . a few had good grades . i had a question in my mind : would hispanic kids react the same way as the american kids ? so i went to colombia . and i reproduced the experiment . and it was very funny . i used four , five and six years old kids . and let me show you what happened . ( spanish ) ( laughter ) so what happened in colombia ? hispanic kids , two out of three ate the marshmallow ; one out of three did not . this little girl was interesting ; she ate the inside of the marshmallow . ( laughter ) in other words , she wanted us to think that she had not eaten it , so she would get two . but she ate it . so we know she 'll be successful . but we have to watch her . ( laughter ) she should not go into banking , for example , or work at a cash register . but she will be successful . and this applies for everything . even in sales . the sales person that -- the customer says , `` i want that . '' and the person says , `` okay , here you are . '' that person ate the marshmallow . if the sales person says , `` wait a second . let me ask you a few questions to see if this is a good choice . '' then you sell a lot more . so this has applications in all walks of life . i end with -- the koreans did this . you know what ? this is so good that we want a marshmallow book for children . we did one for children . and now it is all over korea . they are teaching these kids exactly this principle . and we need to learn that principle here in the states , because we have a big debt . we are eating more marshmallows than we are producing . thank you so much .
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they would play with their skirts and pants . that child already , at four , understood the most important principle for success , which is the ability to delay gratification . self-discipline : the most important factor for success . 15 years later , 14 or 15 years later , follow-up study . what did they find ?
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why do you think mastering delayed self-gratification as a child allows for more success later in life ?
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beneath your ribs , you 'll find , among other things , the pancreas , an organ that works a lot like a personal health coach . this organ controls your sugar levels and produces a special juice that releases the nutrients from your food to help keep you in the best possible shape . the pancreas sits just behind your stomach , an appropriate home , as one of its jobs is to break down the food you eat . it aids digestion by producing a special tonic made of water , sodium bicarbonate , and digestive enzymes . sodium bicarbonate neutralizes the stomach 's natural acidity , so these digestive enzymes can perform their jobs . lipase breaks down fatty substances , protease splits up proteins , and amylase divides carbohydrates to create energy-rich sugars . most of those nutrients then get absorbed into the blood stream , and go on to enrich the body . while all this is happening , the pancreas works on another critical task , controlling the amount of sugar in your blood . it achieves this with the hormones insulin and glucagon , which are produced in special cells called the islets of langerhans . having too much or too little sugar can be life threatening , so the pancreas must stay on constant alert . after a big meal , the blood often becomes flushed with sugar . to bring us back to normal , the pancreas releases insulin , which makes the excess sugar move into cells , where it 's either used as an energy source , or stored for later . insulin also tells the liver to shut down sugar production . on the other hand , if blood sugar is low , the pancreas releases a hormone called glucagon that tells the body 's cells and liver to release stored sugars back into the bloodstream . the interplay between insulin and glucagon is what keeps our sugar levels balanced . but a faulty pancreas can no longer coach us like this , meaning that this healthy balance is destroyed . if it 's weakened by disease , the organ 's ability to produce insulin may be reduced , or even extinguished , which can trigger the condition known as diabetes . without regular insulin release , sugar steadily builds up in the blood , eventually hardening the blood vessels and causing heart attacks , kidney failure , and strokes . the same lack of insulin deprives cells of the energy-rich sugar they need to grow and function . people with diabetes also tend to have higher levels of glucagon , which makes even more sugar circulate . without this internal health coach , our sugar levels would go haywire , and we would n't be able to digest important nutrients . but like any coach , it 's not the pancreas ' job alone to keep us healthy . it needs our conscious participation , too .
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it achieves this with the hormones insulin and glucagon , which are produced in special cells called the islets of langerhans . having too much or too little sugar can be life threatening , so the pancreas must stay on constant alert . after a big meal , the blood often becomes flushed with sugar .
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why do you think the pancreas has to be on constant alert for sugars entering your blood stream ?
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lead is a very soft metal and it ’ s easily moulded into all sorts of shapes . this is a pot , i ’ m not sure what it is from , i got it from an old lab that was being closed down so it was probably made for holding a strong acid because lead is very unreactive . you can see rather nicely here the white colour of lead oxide because it has oxidised over the years and this is the white material that was used for paints . this white lead paint that people use , the oxide of lead , had one rather unfortunate consequence that it reacts with sulphur in the air and in victorian times when people burnt coal they produced a lot of sulphur , and the sulphur reacted with the lead to give a black colour which made the white paint eventually turn grey and if you waited long enough black . and this effect was exploited by one of my former colleagues here professor leslie crombie , who during the war was working for the british admiralty in their research labs on the camouflaging of submarines . now if you want your submarine not to be seen , when it is well away from the coast it needs to be white because if you have a white submarine it does not show up against the sky but , if you are trying to slip into the coast at night and not be seen you need the submarine to be black . so leslie came up with the idea of painting the submarine with lead oxide and when it was going near the coast , some sailors went out on to the outside of the ship and sloshed over a solution of sulphide and seawater and the paint turned black . and so you could then go into the coast , drop your agent , do whatever secret things you wanted to do , and then when you went away from the coast they sloshed hydrogen peroxide with seawater , which turned the sulphite into sulphate , and lead sulphate is white so your submarine went white again . so you could change the colour of your submarine to suit what you were doing in the military operation and nobody would see you . and that was a real thing that happened ? yes , that was a real thing . i don ’ t know how widely it was used but they actually tried it out and it worked . so they just needed to take the chemicals and they could add the seawater to make the solution to put on the submarine . the other very important property of lead is that because the lead atom is heavy it is very good at stopping radioactive particles particularly alpha particles , which are helium nuclei those are the nucleus of the helium atom , or beta particles which are electrons . what you should find that if we put this in the way , it should stop counting almost immediately so let us see if that works . there we go straight back down to background and if we take it away , and it picks back up again . and so people who are working with radioactive samples used to use , and still use , bricks made out of lead . so here are two of the bricks and you can see this is a small one and this one is rather thinner . the problem is that if you start building these bricks into a wall , there is always a chance that when you have two bits together there might be a slight gap between the two bricks and some of the radioactive particles may go between them . so to avoid this the bricks are made with groves in it , and a pointed part here , so that when you put them together there is absolutely no way that anything can go through because you can ’ t have a direct line through it . now the trouble is of course you can ’ t see anything through it , so if you have an experiment where you want to handle radioactive material inside a container and manipulate it you can ’ t make the whole container of lead because you can ’ t see what is going on inside . and so for that , people have developed lead glass , of which this is a sample and it is immensely heavy , but this is glass and there is really a large amount of lead that has been put in it . and some of the fancy crystals that your grandmothers or your ancestors might have had , had a bit of lead in the glass . this has got a really high proportion of lead in the glass which is probably why the glass is yellow rather than the white colour that you normally have with glass . but windows like this can be used for handling really quite radioactive materials behind them . the colour is rather nice isn ’ t it ? good . but it is very heavy , so… well , lead has had a very long history ; it was one of the first metals to be widely used . the romans used this for drinking materials . there is also lead acetate , that is a compound of lead and vinegar is meant to taste sweet and the romans added this to their wine to make it sweeter . the fact that it was really very poisonous and caused , possibly even caused madness , was not really widely recognised . in fact some people have suggested that part of the collapse of the roman empire was due to too much lead . lead was very widely used in the uk for water pipes because it ’ s easy to manufacture and to join together . it tends not to have been very dangerous in terms of drinking water because it gets a coating on the surface so you do not get much lead in the water ; though if you do have a house with lead pipes in , it is usually advisable to change them . it ’ s again , it was used very widely from the 1920s up till the late 70s or 80s as an additive for petrol . in the old days when petrol engines were first introduced , when you came to a hill and put down the accelerator of your car , the engine started misfiring , so-called ‘ pinking ’ , and the whole thing shook . so it was really quite difficult to drive up hills , but then it was discovered that you could put in a compound , so-called tetraethyl lead , which was really very poisonous , but the guy who discovered it washed his hands in public at a press conference saying “ look it ’ s so safe ” , despite the fact that there were people dying in his factory . so it was very widely adopted and so it was only in quite recent times that it was realised how much lead was being blown out into the atmosphere in car exhausts . and so it ’ s now almost everywhere we have lead-free petrol as a result of people realising the poison-ness of lead .
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there we go straight back down to background and if we take it away , and it picks back up again . and so people who are working with radioactive samples used to use , and still use , bricks made out of lead . so here are two of the bricks and you can see this is a small one and this one is rather thinner .
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as the professor explained , where in some old houses can we still find lead ?
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in 1879 , amateur archaeologist marcelino sanz de sautuola and his young daughter maria explored a dark cave in northern spain . when maria wondered off by herself , she made an amazing discovery . they were standing inside a site of ancient art , the walls and roofs decorated with prehistoric paintings and engravings , ranging from 19,000 to 35,000 years old . similar marks of our ancestors have been preserved in caves all over the world . the oldest we 've found were made up to 40,000 years ago . what do these images tell us about the ancient human mind and the lives of their creators ? these early artists mixed minerals , clay , charcoal , and ochre with spit or animal fat to create paint . they drew with their hands and tools , like pads of moss , twigs , bones , and hair . in many instances , their images follow the contours of the cave to create depth and shade . the most common depictions are of geometric shapes , followed by large mammals , like bison , horses , mammoths , deer , and boars . human figures appear rarely , as well as occasional hand prints . some have theorized that these artworks are the creation of hunters , or of holy men in trance-like states . and we 've found examples created by men , women , and even children . and why did they create this art ? perhaps they were documenting what they knew about the natural world , like modern scientists , or marking their tribal territory . maybe the images were the culmination of sacred hunting rituals or spiritual journeys . or could they be art for art 's sake , the sheer joy and fulfillment of creation ? as with many unsolved mysteries of the ancient world , we may never know for sure , barring the invention of a time machine , that is . but while the answers remain elusive , these images are our earliest proof of human communication , testifying to the human capacity for creativity thousands of years before writing . they are a distinct visual language that imagines the world outside the self , just like modern art forms , from graffiti and painting to animated virtual-reality caves .
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some have theorized that these artworks are the creation of hunters , or of holy men in trance-like states . and we 've found examples created by men , women , and even children . and why did they create this art ?
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can you think of examples of other creative arts that mimic or echo aspects of cave paintings ?
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he was one of the most influential figures of the 20th century , forever changing the course of one of the world 's largest countries . but was he a hero who toppled an oppressive tyranny or a villain who replaced it with another ? it 's time to put lenin on the stand in history vs. lenin . `` order , order , hmm . now , was n't it your fault that the band broke up ? '' `` your honor , this is vladimir ilyich ulyanov , aka lenin , the rabblerouser who helped overthrow the russian tsar nicholas ii in 1917 and founded the soviet union , one of the worst dictatorships of the 20th century . '' `` ohh . '' `` the tsar was a bloody tyrant under whom the masses toiled in slavery . '' `` this is rubbish . serfdom had already been abolished in 1861 . '' `` and replaced by something worse . the factory bosses treated the people far worse than their former feudal landlords . and unlike the landlords , they were always there . russian workers toiled for eleven hours a day and were the lowest paid in all of europe . '' `` but tsar nicholas made laws to protect the workers . '' `` he reluctantly did the bare minimum to avert revolution , and even there , he failed . remember what happened in 1905 after his troops fired on peaceful petitioners ? '' `` yes , and the tsar ended the rebellion by introducing a constitution and an elected parliament , the duma . '' `` while retaining absolute power and dissolving them whenever he wanted . '' `` perhaps there would 've been more reforms in due time if radicals , like lenin , were n't always stirring up trouble . '' `` your honor , lenin had seen his older brother aleksandr executed by the previous tsar for revolutionary activity , and even after the reforms , nicholas continued the same mass repression and executions , as well as the unpopular involvement in world war i , that cost russia so many lives and resources . '' `` hm , this tsar does n't sound like such a capital fellow . '' `` your honor , maybe nicholas ii did doom himself with bad decisions , but lenin deserves no credit for this . when the february 1917 uprisings finally forced the tsar to abdicate , lenin was still exiled in switzerland . '' `` hm , so who came to power ? '' `` the duma formed a provisional government , led by alexander kerensky , an incompetent bourgeois failure . he even launched another failed offensive in the war , where russia had already lost so much , instead of ending it like the people wanted . '' `` it was a constitutional social democratic government , the most progressive of its time . and it could have succeeded eventually if lenin had n't returned in april , sent by the germans to undermine the russian war effort and instigate riots . '' `` such slander ! the july days were a spontaneous and justified reaction against the government 's failures . and kerensky showed his true colors when he blamed lenin and arrested and outlawed his bolshevik party , forcing him to flee into exile again . some democracy ! it 's a good thing the government collapsed under their own incompetence and greed when they tried to stage a military coup then had to ask the bolsheviks for help when it backfired . after that , all lenin had to do was return in october and take charge . the government was peacefully overthrown overnight . '' `` but what the bolsheviks did after gaining power was n't very peaceful . how many people did they execute without trial ? and was it really necessary to murder the tsar 's entire family , even the children ? '' `` russia was being attacked by foreign imperialists , trying to restore the tsar . any royal heir that was rescued would be recognized as ruler by foreign governments . it would 've been the end of everything the people had fought so hard to achieve . besides , lenin may not have given the order . '' `` but it was not only imperialists that the bolsheviks killed . what about the purges and executions of other socialist and anarchist parties , their old allies ? what about the tambov rebellion , where peasants , resisting grain confiscation , were killed with poison gas ? or sending the army to crush the workers in kronstadt , who were demanding democratic self-management ? was this still fighting for the people ? '' `` yes ! the measures were difficult , but it was a difficult time . the new government needed to secure itself while being attacked from all sides , so that the socialist order could be established . '' `` and what good came of this socialist order ? even after the civil war was won , there were famines , repression and millions executed or sent to die in camps , while lenin 's successor stalin established a cult of personality and absolute power . '' `` that was n't the plan . lenin never cared for personal gains , even his enemies admitted that he fully believed in his cause , living modestly and working tirelessly from his student days until his too early death . he saw how power-hungry stalin was and tried to warn the party , but it was too late . '' `` and the decades of totalitarianism that followed after ? '' `` you could call it that , but it was lenin 's efforts that changed russia in a few decades from a backward and undeveloped monarchy full of illiterate peasants to a modern , industrial superpower , with one of the world 's best educated populations , unprecedented opportunities for women , and some of the most important scientific advancements of the century . life may not have been luxurious , but nearly everyone had a roof over their head and food on their plate , which few countries have achieved . '' `` but these advances could still have happened , even without lenin and the repressive regime he established . '' `` yes , and i could 've been a famous rock and roll singer . but how would i have sounded ? '' we can never be sure how things could 've unfolded if different people were in power or different decisions were made , but to avoid the mistakes of the past , we must always be willing to put historical figures on trial .
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it 's a good thing the government collapsed under their own incompetence and greed when they tried to stage a military coup then had to ask the bolsheviks for help when it backfired . after that , all lenin had to do was return in october and take charge . the government was peacefully overthrown overnight . ''
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which country helped lenin return from exile during the july days ?
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stretched across a tree-peppered expanse in southern africa lies the magnificent ruins of great zimbabwe , a medieval stone city of astounding wealth and prestige . located in the present-day country of zimbabwe , it 's the sight of the largest known settlement ruins in sub-saharan africa , second on the continent only to the pyramids of egypt . but the history of this city is shrouded in controversy , defined by decades of dispute about who built it and why . its name comes from the shona word madzimbabwe , meaning big house of stone for its unscalable stone walls that reach heights of nearly ten meters and run for a length of about 250 meters . for its grandeur and historical significance , it was named a unesco world heritage site in 1986 . back in the 14th and 15th centuries , it was a thriving city . spread across nearly eight square-kilometers , great zimbabwe was defined by three main areas : the hill complex , where the king lived ; the great enclosure , reserved for members of the royal family ; and the valley complex , where regular citizens lived . rulers were both powerful economic and religious leaders for the region . at its highest point , the city had a bustling urban population of 18,000 people and was one of the major african trade centers at the time . what enabled this growth was great zimbabwe 's influential role in an intercontinental trade network . connected to several key city-states along the east african swahili coast , it was part of the larger indian ocean trade routes . the city generated its riches by controlling the sources and trade of the most prized items : gold , ivory , and copper . with this mercantile power , it was able to extend its sphere of influence across continents , fostering a strong arab and indian trader presence throughout its zenith . archaeologists have since pieced together the details of this history through artifacts discovered on site . there were pottery shards and glassworks from asia , as well as coins minted in the coastal trading city of kilwa kisiwani over 1,500 miles away . they also found soapstone bird figures , which are thought to represent each of the city 's rulers , and young calf bones , only unearthed near the royal residence , show how the diet of the elite differed from the general population . these clues have also led to theories about the city 's decline . by the mid-15th century , the buildings at great zimbabwe were almost all that remained . archaeological evidence points to overcrowding and sanitation issues as the cause , compounded by soil depletion triggered by overuse . eventually , as crops withered and conditions in the city worsened , the population of great zimbabwe is thought to have dispersed and formed the nearby mutapa and torwa states . centuries later , a new phase of great zimbabwe 's influence began to play out in the political realm as people debated who had built the famous city of stone . during the european colonization of africa , racist colonial officials claimed the ruins could n't be of african origin . so , without a detailed written record on hand , they instead relied on myths to explain the magnificence of great zimbabwe . some claimed it proved the bible story of the queen of sheba who lived in a city of riches . others argued it was built by the ancient greeks . then , in the early 20th century after extensive excavation at the site , the archaeologist david randall-maciver presented clear evidence that great zimbabwe was built by indigenous peoples . yet , at the time , the country 's white minority colonial government sought to discredit this theory because it challenged the legitimacy of their rule . in fact , the government actively encouraged historians to produce accounts that disputed the city 's african origins . over time , however , an overwhelming body of evidence mounted , identifying great zimbabwe as an african city built by africans . during the 1960s and 70s , great zimbabwe became an important symbol for the african nationalist movement that was spreading across the continent . today , the ruins at great zimbabwe , alluded to on the zimbabwean flag by a soapstone bird , still stand as a source of national pride and cultural value .
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they also found soapstone bird figures , which are thought to represent each of the city 's rulers , and young calf bones , only unearthed near the royal residence , show how the diet of the elite differed from the general population . these clues have also led to theories about the city 's decline . by the mid-15th century , the buildings at great zimbabwe were almost all that remained .
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what likely led to great zimbabwe ’ s decline ?
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the sight of mistletoe may either send you scurrying , or if you have your eye on someone , awaiting an opportunity beneath its snow white berries , but how did the festive christmas tradition of kissing under mistletoe come about ? the long-lived custom intertwines the mythology and biology of this intriguing plant . there are more than 1,000 species of mistletoe , which grows the world over . in fact , the ancient europeans were so captivated by the plant 's unusual growth habits that they included it in their legends and myths . in ancient rome , pliny the elder described how the druid priesthood in ancient england believed that mistletoe was a plant dropped down from heaven by the gods . that explained its unlikely position amongst the high branches of certain trees . they also believed it had powers of healing and bestowing fertility . meanwhile , scandinavian legend told of the plant 's mystical qualities in the story of the god baldr and his adoring mother frigg , goddess of love , marriage , and fertility . frigg loved her son so much that she commanded every plant , animal , and inanimate object to vow they 'd never harm him . in her fervor , however , she overlooked the mistletoe . the mischievous god loki realized this oversight and pierced baldr 's heart with an arrow carved from a mistletoe branch . frigg cried tears of such sadness that they formed the mistletoe 's pearly berries , making the other gods pity her and agree to resurrect baldr . hearing the news , frigg became so overjoyed that she transformed the mistletoe from a symbol of death into one of peace and love . she mandated a one-day truce for all fights , and that everyone embrace beneath its branches when they passed to spread more love into the world . in the 17th century , british colonists arriving in the new world found a different , but very similar looking , species of mistletoe . they applied it to these tales of magic , fertility , and love , spreading the mistletoe-hanging tradition from europe into america . by the 18th century , people in britain had turned this into a christmas tradition , but this custom comes down to more than just human imagination . all of it was inspired by the plant 's intriguing biology . we see mistletoe as a festive decoration , but draped on tree boughs in the wild , it 's known as a partly parasitic plant . mistletoe relies on modified roots called haustoria that penetrate the tree bark and siphon off the water and minerals trees carry up their trunks to colonize nearby trees with its seeds , mistletoe depends on birds and other creatures to do the dispersing . birds that eat the mistletoe 's sticky white berries sometimes get rid of the gluey seeds by wiping them off onto tree bark . or with a bit of luck , they excrete the indigestible seed onto a tree where it germinates and starts to grow . with its resilience and foliage that stays lush even while the surrounding trees lose their leaves , you can see why mistletoe captivated our superstitious ancestors . they saw these as signs of the plant 's magical qualities and fertility . even today , the mistletoe inspires wonder with the diversity of wildlife it supports . more than just a parasite , it 's also known as a keystone species . it 's eaten by a diversity of animals , including deer , elk , squirrels , chipmunks , porcupines , robins , bluebirds , morning doves , and the butterfly genus delias . some mistletoe species produce dense bushes , which are excellent nesting locations for a variety of birds . and despite their parasitic relationship with trees , mistletoes can also help other plants . for instance , juniper sprouts near mistletoe to benefit from the visiting berry-eating birds . through the many benefits it provides , mistletoe influences diversity , and allows ecosystems to flourish . you might even say that for this iconic plant , life imitates legend . in the wild , mistletoe has the power to bring things together , and in our own traditions , we see that happening , too .
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in fact , the ancient europeans were so captivated by the plant 's unusual growth habits that they included it in their legends and myths . in ancient rome , pliny the elder described how the druid priesthood in ancient england believed that mistletoe was a plant dropped down from heaven by the gods . that explained its unlikely position amongst the high branches of certain trees .
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the ancient british druids believed the mistletoe was dropped from heaven by :
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we read fiction for many reasons . to be entertained , to find out who done it , to travel to strange , new planets , to be scared , to laugh , to cry , to think , to feel , to be so absorbed that for a while we forget where we are . so , how about writing fiction ? how do you suck your readers into your stories ? with an exciting plot ? maybe . fascinating characters ? probably . beautiful language ? perhaps . `` billie 's legs are noodles . the ends of her hair are poison needles . her tongue is a bristly sponge , and her eyes are bags of bleach . '' did that description almost make you feel as queasy as billie ? we grasp that billie 's legs are n't actually noodles . to billie , they feel as limp as cooked noodles . it 's an implied comparison , a metaphor . so , why not simply write it like this ? `` billie feels nauseated and weak . '' chances are the second description was n't as vivid to you as the first . the point of fiction is to cast a spell , a momentary illusion that you are living in the world of the story . fiction engages the senses , helps us create vivid mental simulacra of the experiences the characters are having . stage and screen engage some of our senses directly . we see and hear the interactions of the characters and the setting . but with prose fiction , all you have is static symbols on a contrasting background . if you describe the story in matter of fact , non-tactile language , the spell risks being a weak one . your reader may not get much beyond interpreting the squiggles . she will understand what billie feels like , but she wo n't feel what billie feels . she 'll be reading , not immersed in the world of the story , discovering the truths of billie 's life at the same time that billie herself does . fiction plays with our senses : taste , smell , touch , hearing , sight , and the sense of motion . it also plays with our ability to abstract and make complex associations . look at the following sentence . `` the world was ghost-quiet , except for the crack of sails and the burbling of water against hull . '' the words , `` quiet , '' `` crack , '' and `` burbling , '' engage the sense of hearing . notice that buckell does n't use the generic word sound . each word he chooses evokes a particular quality of sound . then , like an artist laying on washes of color to give the sense of texture to a painting , he adds anoter layer , motion , `` the crack of sails , '' and touch , `` the burbling of water against hull . '' finally , he gives us an abstract connection by linking the word quiet with the word ghost . not `` quiet as a ghost , '' which would put a distancing layer of simile between the reader and the experience . instead , buckell creates the metaphor `` ghost-quiet '' for an implied , rather than overt , comparison . writers are always told to avoid cliches because there 's very little engagement for the reader in an overused image , such as `` red as a rose . '' but give them , `` love ... began on a beach . it began that day when jacob saw anette in her stewed-cherry dress , '' and their brains engage in the absorbing task of figuring out what a stewed-cherry dress is like . suddenly , they 're on a beach about to fall in love . they 're experiencing the story at both a visceral and a conceptual level , meeting the writer halfway in the imaginative play of creating a dynamic world of the senses . so when you write , use well-chosen words to engage sound , sight , taste , touch , smell , and movement . then create unexpected connotations among your story elements , and set your readers ' brushfire imaginations alight .
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to be entertained , to find out who done it , to travel to strange , new planets , to be scared , to laugh , to cry , to think , to feel , to be so absorbed that for a while we forget where we are . so , how about writing fiction ? how do you suck your readers into your stories ?
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which of the following purposes does fiction serve ?
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when you think about the brain , it 's difficult to understand , because if i were to ask you right now , how does the heart work , you would instantly tell me it 's a pump . it pumps blood . if i were to ask about your lungs , you would say it exchanges oxygen for carbon dioxide . that 's easy . if i were to ask you how the brain works , it 's hard to understand because you ca n't just look at a brain and understand what it is . it 's not a mechanical object , not a pump , not an airbag . it 's just like , if you held it in your hand when it was dead , it 's just a piece of fat . to understand how the brain works , you have to go inside a living brain . because the brain 's not mechanical , the brain is electrical and it 's chemical . your brain is made out of 100 billion cells , called neurons . and these neurons communicate with each other with electricity . and we 're going to eavesdrop in on a conversation between two cells , and we 're going to listen to something called a spike . but we 're not going to record my brain or your brain or your teachers ' brains , we 're going to use our good friend the cockroach . not just because i think they 're cool , but because they have brains very similar to ours . so if you learn a little bit about how their brains work , we 're going to learn a lot about how our brains work . i 'm going to put them in some ice water here and then -- audience : ew ! greg gabe : yeah ... right now they 're becoming anesthetized . because they 're cold blooded , they become the temperature of the water and they ca n't control it so they just basically `` chillax , '' right ? they 're not going to feel anything , which may tell you a little about what we 're going to do , a scientific experiment to understand the brain . so ... this is the leg of a cockroach . and a cockroach has all these beautiful hairs and pricklies all over it . underneath each one of those is a cell , and this cell 's a neuron that is going to send information about wind or vibration . if you ever try to catch a cockroach , it 's hard because they can feel you coming before you 're even there , they start running . these cells are zipping up this information up to the brain using those little axons with electronic messages in there . we 're going to record by sticking a pin right in there . we need to take off the leg of a cockroach -- do n't worry , they 'll grow back -- then we 're going to put two pins in there . these are metal pins . one will pick up this electronic message , this electric message is going by . so , we 're now going to do the surgery , let 's see if you guys can see this . yeah , it 's gross ... all right . so there we go . you guys can see his leg right there . now i 'm going to take this leg , i 'm going to put it in this invention that we came up with called the spikerbox -- and this replaces lots of expensive equipment in a research lab , so you guys can do this in your own high schools , or in your own basements if it 's me . ( audience : laughter ) so , there . can you guys see that ? alright , so i 'm going to go ahead and turn this on . i 'm going to plug it in . ( tuning sound ) to me , this is the most beautiful sound in the world . this is what your brain is doing right now . you have 100 billion cells making these raindrop-type noises . let 's take a look at what it looks like , let 's pull it up on the ipad screen . i plugged my ipad into here as well . so remember we said the axon looks like a spike . so we 're going to take a look at what one of them looks like in just a brief second . we 're going to tap here , so we can sort of average this guy . so there we see it . that 's an action potential . you 've got 100 billion cells in your brain doing this right now , sending all this information back about what you 're seeing , hearing . we also said this is a cell that 's going to be taking up information about vibrations in the wind . so what if we do an experiment ? we can actually blow on this and hear if we see a change . are you guys going to be ready ? if i blow on it you tell me if you hear anything . ( blowing ) ( sound changes ) let me just touch this with a little pen here . ( noise ) that was the neural firing rate . that actually took a while in neuroscience to understand this . this is called rate coding : the harder you press on something , the more spikes there are , and all that information is coming up to your brain . that 's how you perceive things . so that 's one way of doing an experiment with electricity . the other way is that your brain is not only taking in electrical impulses , you 're also sending out . that 's how you move your muscles around . let 's see what happens if i 've plugged in something that 's electric into the cockroach leg here . i 'm going to take two pins , i 'm going to plug them onto the cockroach . i 'm going to take the other end , i 'm going to plug in into my ipod . it 's my iphone actually . do you guys know how your earbuds work in your ears ? you have a battery in your phone , or ipod , right ? it 's sending electrical current into these magnets in your earbuds which shake back and forth and allow you to hear things . but that current 's the same currency that our brain uses , so we can send that to our cockroach leg and hopefully if this works , we can actually see what happens when we play music into the cockroach . let 's take a look . ( music beat ) can we turn it up ? there we go . ( audience reacts and gasps ) gg : so what 's happening ? audience : wow ! ( laughter ) so you see what 's moving . it 's moving on the bass . all those audiophiles out there , if you have awesome , kicking car stereos , you know , the bass speakers are the biggest speakers . the biggest speakers have the longest waves , which have the most current , and the current is what 's causing these things to move . so it 's not just speakers that are causing electricity . microphones also cause electricity . ( beat ) so i 'm going to go ahead and invite another person out on the stage here to help me out with this . so there we go . ( beatboxing ) this is the first time this has ever happened in the history of mankind . human beatbox to a cockroach leg . when you guys go back to your high school , think about neuroscience and how you guys can begin the neuro-revolution . thank you very much . bye bye . ( applause )
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we also said this is a cell that 's going to be taking up information about vibrations in the wind . so what if we do an experiment ? we can actually blow on this and hear if we see a change .
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there ’ s a lot of research on the benefits of “ hands-on ” science instruction—that is , actively engaging in experiments , versus reading about them in textbooks or watching videos of others performing experiments . what ’ s your feeling about the value of experiments in your science classes ? what ’ s the most interesting—or the most boring—experiment you ’ ve ever done , and why ?
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there 's a common misconception that if you like to meticulously organize your things , keep your hands clean , or plan out your weekend to the last detail , you might have ocd . in fact , ocd , which stands for obsessive compulsive disorder , is a serious psychiatric condition that is frequently misunderstood by society and mental health professionals alike . so let 's start by debunking some myths . myth one : repetitive or ritualistic behaviors are synonymous with ocd . as its name suggests , obsessive compulsive disorder has two aspects : the intrusive thoughts , images , or impulses , known as obsessions , and the behavioral compulsions people engage in to relieve the anxiety the obsessions cause . the kinds of actions that people often associate with ocd , like excessive hand washing , or checking things repeatedly , may be examples of obsessive or compulsive tendencies that many of us exhibit from time to time . but the actual disorder is far more rare and can be quite debilitating . people affected have little or no control over their obsessive thoughts and compulsive behaviors , which tend to be time consuming and interfere with work , school or social life to the point of causing significant distress . this set of diagnostic criteria is what separates people suffering from ocd from those who may just be a bit more meticulous or hygiene obsessed than usual . myth two : the main symptom of ocd is excessive hand washing . although hand washing is the most common image of ocd in popular culture , obsessions and compulsions can take many different forms . obsessions can manifest as fears of contamination and illness , worries about harming others , or preoccupations with numbers , patterns , morality , or sexual identity . and compulsions can range from excessive cleaning or double checking , to the fastidious arrangement of objects , or walking in predetermined patterns . myth three : individuals with ocd do n't understand that they are acting irrationally . many individuals with ocd actually understand the relationship between their obsessions and compulsions quite well . being unable to avoid these thoughts and actions despite being aware of their irrationality is part of the reason why ocd is so distressing . ocd sufferers report feeling crazy for experiencing anxiety based on irrational thoughts and finding it difficult to control their responses . so what exactly causes ocd ? the frustrating answer is we do n't really know . however , we have some important clues . ocd is considered a neurobiological disorder . in other words , research suggests that ocd sufferers brains are actually hardwired to behave in a certain fashion . research has implicated three regions of the brain variously involved in social behavior and complex cognitive planning , voluntary movement , and emotional and motivational responses . the other piece of the puzzle is that ocd is associated with low levels of serotonin , a neurotransmitter that communicates between brain structures and helps regulate vital processes , such as mood , aggression , impulse control , sleep , appetite , body temperature and pain . but are serotonin and activity in these brain regions the sources of ocd or symptoms of an unknown underlying cause of the disorder . we probably wo n't know until we have a much more intimate understanding of the brain . the good news is there are effective treatments for ocd , including medications , which increase serotonin in the brain by limiting its reabsorption by brain cells , behavioral therapy that gradually desensitizes patients to their anxieties , and in some cases , electroconvulsive therapy , or surgery , when ocd does n't respond to other forms of treatment . knowing that your own brain is lying to you while not being able to resist its commands can be agonizing . but with knowledge and understanding comes the power to seek help , and future research into the brain may finally provide the answers we 're looking for .
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myth one : repetitive or ritualistic behaviors are synonymous with ocd . as its name suggests , obsessive compulsive disorder has two aspects : the intrusive thoughts , images , or impulses , known as obsessions , and the behavioral compulsions people engage in to relieve the anxiety the obsessions cause . the kinds of actions that people often associate with ocd , like excessive hand washing , or checking things repeatedly , may be examples of obsessive or compulsive tendencies that many of us exhibit from time to time .
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all of the following are types of obsessions except ?
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have you ever sat in a doctor 's office for hours despite having an appointment at a specific time ? has a hotel turned down your reservation because it 's full ? or have you been bumped off a flight that you paid for ? these are all symptoms of overbooking , a practice where businesses and institutions sell or book more than their full capacity . while often infuriating for the customer , overbooking happens because it increases profits while also letting businesses optimize their resources . they know that not everyone will show up to their appointments , reservations , and flights , so they make more available than they actually have to offer . airlines are the classical example , partially because it happens so often . about 50,000 people get bumped off their flights each year . that figure comes at little surprise to the airlines themselves , which use statistics to determine exactly how many tickets to sell . it 's a delicate operation . sell too few , and they 're wasting seats . sell too many , and they pay penalties - money , free flights , hotel stays , and annoyed customers . so here 's a simplified version of how their calculations work . airlines have collected years worth of information about who does and does n't show up for certain flights . they know , for example , that on a particular route , the probability that each individual customer will show up on time is 90 % . for the sake of simplicity , we 'll assume that every customer is traveling individually rather than as families or groups . then , if there are 180 seats on the plane and they sell 180 tickets , the most likely result is that 162 passengers will board . but , of course , you could also end up with more passengers , or fewer . the probability for each value is given by what 's called a binomial distribution , which peaks at the most likely outcome . now let 's look at the revenue . the airline makes money from each ticket buyer and loses money for each person who gets bumped . let 's say a ticket costs $ 250 and is n't exchangeable for a later flight . and the cost of bumping a passenger is $ 800 . these numbers are just for the sake of example . actual amounts vary considerably . so here , if you do n't sell any extra tickets , you make $ 45,000 . if you sell 15 extras and at least 15 people are no shows , you make $ 48,750 . that 's the best case . in the worst case , everyone shows up . 15 unlucky passengers get bumped , and the revenue will only be $ 36,750 , even less than if you only sold 180 tickets in the first place . but what matters is n't just how good or bad a scenario is financially , but how likely it is to happen . so how likely is each scenario ? we can find out by using the binomial distribution . in this example , the probability of exactly 195 passengers boarding is almost 0 % . the probability of exactly 184 passengers boarding is 1.11 % , and so on . multiply these probabilities by the revenue for each case , add them all up , and subtract the sum from the earnings by 195 sold tickets , and you get the expected revenue for selling 195 tickets . by repeating this calculation for various numbers of extra tickets , the airline can find the one likely to yield the highest revenue . in this example , that 's 198 tickets , from which the airline will probably make $ 48,774 , almost 4,000 more than without overbooking . and that 's just for one flight . multiply that by a million flights per airline per year , and overbooking adds up fast . of course , the actual calculation is much more complicated . airlines apply many factors to create even more accurate models . but should they ? some argue that overbooking is unethical . you 're charging two people for the same resource . of course , if you 're 100 % sure someone wo n't show up , it 's fine to sell their seat . but what if you 're only 95 % sure ? 75 % ? is there a number that separates being unethical from being practical ?
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but should they ? some argue that overbooking is unethical . you 're charging two people for the same resource .
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what types of motivation , besides profit maximization , could be at play when overbooking a flight ?
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what happens after death ? is there a restful paradise ? an eternal torment ? a rebirth ? or maybe just nothingness ? well , one chinese emperor thought that whatever the hereafter was , he better bring an army . we know that because in 1974 , farmers digging a well near their small village stumbled upon one of the most important finds in archeological history : vast underground chambers surrounding that emperor 's tomb , and containing more than 8,000 life-size clay soldiers ready for battle . the story of the subterranean army begins with ying zheng , who came to power as the king of the qin state at the age of 13 in 246 bce . ambitious and ruthless , he would go on to become qin shi huangdi , the first emperor of china after uniting its seven warring kingdoms . his 36 year reign saw many historic accomplishments , including a universal system of weights and measures , a single standardized writing script for all of china , and a defensive barrier that would later come to be known as the great wall . but perhaps qin shi huangdi dedicated so much effort to securing his historical legacy because he was obsessed with his mortality . he spent his last years desperately employing alchemists and deploying expeditions in search of elixirs of life that would help him achieve immortality . and as early as the first year of his reign , he began the construction of a massive underground necropolis filled with monuments , artifacts , and an army to accompany him into the next world and continue his rule . this magnificent army is still standing in precise battle formation and is split across several pits . one contains a main force of 6,000 soldiers , each weighing several hundred pounds , a second has more than 130 war chariots and over 600 horses , and a third houses the high command . an empty fourth pit suggests that the grand project could not be finished before the emperor 's death . in addition , nearby chambers contain figures of musicians and acrobats , workers and government officials , and various exotic animals , indicating that emperor qin had more plans for the afterlife than simply waging war . all the figurines are sculpted from terracotta , or baked earth , a type of reddish brown clay . to construct them , multiple workshops and reportedly over 720,000 laborers were commandeered by the emperor , including groups of artisans who molded each body part separately to construct statues as individual as the real warriors in the emperor 's army . they stand according to rank and feature different weapons and uniforms , distinct hairstyles and expressions , and even unique ears . originally , each warrior was painted in bright colors , but their exposure to air caused the paint to dry and flake , leaving only the terracotta base . it is for this very reason that another chamber less than a mile away has not been excavated . this is the actual tomb of qin shi huangdi , reported to contain palaces , precious stones and artifacts , and even rivers of mercury flowing through mountains of bronze . but until a way can be found to expose it without damaging the treasures inside , the tomb remains sealed . emperor qin was not alone in wanting company for his final destination . ancient egyptian tombs contain clay models representing the ideal afterlife , the dead of japan 's kofun period were buried with sculptures of horses and houses , and the graves of the jaina island off the mexican coast are full of ceramic figurines . fortunately , as ruthless as he was , emperor qin chose to have servants and soldiers built for this purpose , rather than sacrificing living ones to accompany him , as had been practiced in egypt , west africa , anatolia , parts of north america and even china during the previous shang and zhou dynasties . and today , people travel from all over the world to see these stoic soldiers silently awaiting their battle orders for centuries to come .
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or maybe just nothingness ? well , one chinese emperor thought that whatever the hereafter was , he better bring an army . we know that because in 1974 , farmers digging a well near their small village stumbled upon one of the most important finds in archeological history : vast underground chambers surrounding that emperor 's tomb , and containing more than 8,000 life-size clay soldiers ready for battle .
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what insights can the terracotta warriors provide us about chinese history ?
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translator : andrea mcdonough reviewer : bedirhan cinar one of the grandest scientific tools ever made by mankind is called an atom smasher . and i mean literally grand . the biggest one ever built , the large hadron collider , or lhc , is a ring with a circumference of about 18 miles . that 's more than the entire length of manhattan . so what is an atom smasher ? it is a device that collides atomic nuclei together at extremely high energy . the most powerful one scientists have ever built can heat matter to the hottest temperatures ever achieved , temperatures last seen at a trillionth of second after the universe began . our accelerators are full of engineering superlatives . the beam-containing region of the lhc is a vacuum , with lower pressure than what surrounds the international space station , and is 456 degrees fahrenheit below zero , colder than the temperature of deepest space . a previous accelerator sitting in the lhc tunnel holds the world record for velocity , accelerating an electron to a speed so fast that if it were to race a photon of light , it would take about 14 minutes for the photon to get a lead of about 10 feet . if that does n't impress you , remember the photon is fastest thing in the universe , it goes about 186,000 miles per second . so how do these subatomic particle accelerators work ? well , they use electric fields . electric fields make charged particles move in the same way that gravity will pull a dropped baseball . the force from the electric field will pull a particle to make it move . the speed will continue to increase until the charged particle is moving incredibly fast . a simple particle accelerator can be made by hooking two parallel metal plates to a battery . the charge from the battery moves on to the two metal plates and makes an electric field that pulls the particle along . and that 's it , you got a particle accelerator . the problem is that an accelerator built this way is very weak . building a modern accelerator like the lhc this way would take over five trillion standard d-cell batteries . so scientists use much stronger batteries and put them one after another . an earlier accelerator used this method and was about a mile long and was equivalent to 30 billion batteries . however , to make an accelerator that is equivalent to five trillion batteries would require an accelerator 150 miles long . scientists needed another way . while electric fields would make a particle go faster , magnetic fields make them move in a circular path . if you put an electric field along the circle , you do n't need to use miles of electric fields , you can use a single electric field over and over again . the beams go around the circle , and each time they gain more energy . so very high-energy accelerators consist of a short region with accelerating electric fields , combined with long series of magnets that guide the particles in a circle . the strength of the magnets and the radius of the circular path determines the maximum energy of the beam . once the beam is zooming along , then the real fun begins , the smashing . the reason physicists want to get those particles moving so fast is so that they can slam them into one another . these collisions can teach us about the fundamental rules that govern matter , but they 'd be impossible without the feat of engineering that is the particle accelerator .
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if that does n't impress you , remember the photon is fastest thing in the universe , it goes about 186,000 miles per second . so how do these subatomic particle accelerators work ? well , they use electric fields .
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particle accelerators are used to give subatomic particles tremendous velocities . how is this connected to the study of incredibly hot collisions ?
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this may look like a neatly arranged stack of numbers , but it 's actually a mathematical treasure trove . indian mathematicians called it the staircase of mount meru . in iran , it 's the khayyam triangle . and in china , it 's yang hui 's triangle . to much of the western world , it 's known as pascal 's triangle after french mathematician blaise pascal , which seems a bit unfair since he was clearly late to the party , but he still had a lot to contribute . so what is it about this that has so intrigued mathematicians the world over ? in short , it 's full of patterns and secrets . first and foremost , there 's the pattern that generates it . start with one and imagine invisible zeros on either side of it . add them together in pairs , and you 'll generate the next row . now , do that again and again . keep going and you 'll wind up with something like this , though really pascal 's triangle goes on infinitely . now , each row corresponds to what 's called the coefficients of a binomial expansion of the form ( x+y ) ^n , where n is the number of the row , and we start counting from zero . so if you make n=2 and expand it , you get ( x^2 ) + 2xy + ( y^2 ) . the coefficients , or numbers in front of the variables , are the same as the numbers in that row of pascal 's triangle . you 'll see the same thing with n=3 , which expands to this . so the triangle is a quick and easy way to look up all of these coefficients . but there 's much more . for example , add up the numbers in each row , and you 'll get successive powers of two . or in a given row , treat each number as part of a decimal expansion . in other words , row two is ( 1x1 ) + ( 2x10 ) + ( 1x100 ) . you get 121 , which is 11^2 . and take a look at what happens when you do the same thing to row six . it adds up to 1,771,561 , which is 11^6 , and so on . there are also geometric applications . look at the diagonals . the first two are n't very interesting : all ones , and then the positive integers , also known as natural numbers . but the numbers in the next diagonal are called the triangular numbers because if you take that many dots , you can stack them into equilateral triangles . the next diagonal has the tetrahedral numbers because similarly , you can stack that many spheres into tetrahedra . or how about this : shade in all of the odd numbers . it does n't look like much when the triangle 's small , but if you add thousands of rows , you get a fractal known as sierpinski 's triangle . this triangle is n't just a mathematical work of art . it 's also quite useful , especially when it comes to probability and calculations in the domain of combinatorics . say you want to have five children , and would like to know the probability of having your dream family of three girls and two boys . in the binomial expansion , that corresponds to girl plus boy to the fifth power . so we look at the row five , where the first number corresponds to five girls , and the last corresponds to five boys . the third number is what we 're looking for . ten out of the sum of all the possibilities in the row . so 10/32 , or 31.25 % . or , if you 're randomly picking a five-player basketball team out of a group of twelve friends , how many possible groups of five are there ? in combinatoric terms , this problem would be phrased as twelve choose five , and could be calculated with this formula , or you could just look at the sixth element of row twelve on the triangle and get your answer . the patterns in pascal 's triangle are a testament to the elegantly interwoven fabric of mathematics . and it 's still revealing fresh secrets to this day . for example , mathematicians recently discovered a way to expand it to these kinds of polynomials . what might we find next ? well , that 's up to you .
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or how about this : shade in all of the odd numbers . it does n't look like much when the triangle 's small , but if you add thousands of rows , you get a fractal known as sierpinski 's triangle . this triangle is n't just a mathematical work of art . it 's also quite useful , especially when it comes to probability and calculations in the domain of combinatorics .
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in pascal 's triangle , 11^3 has the value in the row corresponding to n=_____ .
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