I am an Indian citizen and traveling to Seattle (on Business visa) through Tokyo (Layover for 9 hours). I don't have any such plans to go outside from the airport in Tokyo. Do I still need a Transit visa for staying in Airport transit zone in Tokyo?  Do I need to cross the Immigration boxes while transferring the flights?
I will be transferring between two international flights at Tokyo Narita airport. I'm scheduled to depart the same day I arrive. I am planning to stay within the airport during the layover. Does anyone know if I will require a transit visa at Narita?
I've seen several examples of code like this:  if not someobj:     #do something   But I'm wondering why not doing:  if someobj == None:     #do something   Is there any difference? Does one have an advantage over the other? I've been trying to solve the following problem:  Suppose that $f$ and $f&#39;$ are continuous functions on $\mathbb{R}$, and that $\displaystyle\lim_{x\to\infty}f(x)$ and $\displaystyle\lim_{x\to\infty}f&#39;(x)$ exist. Show that $\displaystyle\lim_{x\to\infty}f&#39;(x) = 0$.  I'm not entirely sure what to do. Since there's not a lot of information given, I guess there isn't very much one can do. I tried using the definition of the derivative and showing that it went to $0$ as $x$ went to $\infty$ but that didn't really work out. Now I'm thinking I should assume $\displaystyle\lim_{x\to\infty}f&#39;(x) = L \neq 0$ and try to get a contradiction, but I'm not sure where the contradiction would come from.   Could somebody point me in the right direction (e.g. a certain theorem or property I have to use?) Thanks Asking users to accept answer when they comment that it answers their question I make heavy use of screen's "log" command to log the output of a session to a file, when I am making changes in a given environment. I searched through tmux's man page, but couldn't find an equivalent. Is anyone aware of a similar feature in tmux, or do I have to write my own wrapper scripts to do this?  EDIT: I'm aware of 'script' and other utilities that allow me to log a session. The reason that screen's functionality is so useful is the ability to define a logfile variable which uses string escapes to uniquely identify each session.  e.g. I have a shell function which, given a hostname, will SSH to that host in a new screen window and set the window title to the hostname. When I start a log of that session, it is prefixed with the window title.  If this functionality doesn't exist in tmux, I'll have to create a new set of shell functions to set up 'scripts' of sessions I want to log. This isn't hugely difficult, but it may not be worth the effort given that screen does exactly what I need already. Where are the outliner toggles in 2.8? Why does Hermione say she hadn't used a memory charm before? After the wedding, Hermione has to use a memory charm on two Death Eaters, where she states that she has never done it before, but she knows the theory. However, she states that before she left on her adventure, she made her parents forget her, and move to Australia. Is this a contradiction, or is there an explanation? If cooking meat kills bacteria, and bacteria are responsible for problems with eating meat which has been left out, then why is it dangerous to eat meat which has been left out at room temperature and then thoroughly cooked?   mentions that "Even if the bacteria is dead, toxins can remain if the food was out too long, causing problems".  However, there's no further detail given.  Are these toxins as dangerous as the bacteria themselves?  How long does meat have to be left out to accumulate a dangerous level of toxins and thus be dangerous even if thoroughly cooked?  Are these toxins the reason for the usual guideline of keeping meat unrefrigerated for a maximum of 2 hours?  update  The revelation, courtesy of Aaronut, that e. coli is actually dangerous because of its toxins — which cannot be denatured at temperatures which will leave meat in an edible state — has pretty much answered this question.  And also given me further incentive to stop eating meat altogether :)  Our discussion (see the comments on hobodave's answer) has progressed into the realm of microbiology.  Some highlights from my ongoing research:  .  These seem to be the reason for the importance of keeping meat at a high temperature for a period of time.  .  This also provides fascinating insight into how bacteria evolved immunity to antibiotics.  Fungi. Upper bound for $\sqrt[n]{n!}$ I am a bit confused. When can we omit the preposition on before weekdays? (Monday, Tuesday etc.) Sometimes I read weekdays without the preposition on. If the preposition is left out, does it work the same way, or does it change the meaning?  Example without the preposition     The UGC issued the public notice Monday after its two previous orders   in this regard were overlooked by the DU.   Example with the preposition     The commission on Monday also issued a public notice against the FYUP   in all leading newspapers for parents and students. Prove that if $a \mid b$ then $\gcd(a,b) = |a|$ I'm trying to make a command block that spawns an item in front of you if you are holding an item with a specific name. I've got these two working scripts;  /testfor @p[r=10] {Inventory:[{tag:{display:{Name:"Item Name"}}}]}  /testfor @p[r=10] {SelectedItemSlot:0,Inventory:[{Slot:0b,­id:"minecraft:diamond_sword"}]­}   but I can't get them together. The block should only look for an item in the active slot. When initiating a battle it starts off in AR mode, but then warns me saying my phone's orientation is not detected. I am then forced to turn off AR mode. Has anybody experienced this? If so, what are the solutions?    Per comments, I am unsure this is a permissions issue. I have everything turned on. Getting the default text editor used in system I have used select-editor and I note that I am using /usr/bin/nano. Is this the default text editor I am using?  When I open text files, It opens with gedit  What command in terminal must be specified to get the default text editor that I am using, and have it returned to e in terminal? To all the 'sed' doctors out there:  How can you get 'sed' to extract a regular expression it has matched in a  line?   In other words words, I want just the string corresponding to the regular  expression with all the non-matching characters from the containing line stripped away.  I tried using the back-reference feature like below  regular expression to be isolated           gets `inserted`                here                     |                v    sed -n 's/.*\( \).*/\1/p    this works for some expressions like   sed -n 's/.*\(CONFIG_[a-zA-Z0-9_]*\).*/\1/p    which neatly extracts all macro names starting with 'CONFIG_ ....' ( found in some '*.h' file ) and prints them all out line by line             CONFIG_AT91_GPIO           CONFIG_DRIVER_AT91EMAC                    .                    .              CONFIG_USB_ATMEL           CONFIG_USB_OHCI_NEW                    .                  e.t.c.    BUT the above breaks down for something like    sed -n 's/.*\([0-9][0-9]*\).*/\1/p    this always returns single digits like                    7                  9                  .                  .                    6   rather than extracting a contiguous number field such as.                 8908078               89670890                    .                  .                    .                23019                     .                e.t.c.     P.S.: I would be grateful to feedback on how this is achieved in 'sed'.        I know how to do this with 'grep' and 'awk'       I would like to find out if my - albeit limited - understanding of        'sed' has holes in it and if there is way to do this in 'sed' which I       have simply overlooked. What is the mechanism by which magnetic fields do work? I've seen some conflicted answers to this question in texts and on the web, in the case of a dipole, for example.   Do magnetic fields do work directly, or is it their induced electric fields that do work? Prove that $$1+\frac{1}{3}+\frac{1\cdot 3}{3\cdot 6}+\frac{1\cdot 3\cdot 5}{3\cdot 6 \cdot 9}+.........=\sqrt{3}$$   $\bf{My\; Try::}$ Using Binomial expansion of  $$(1-x)^{-n} = 1+nx+\frac{n(n+1)}{2}x^2+\frac{n(n+1)(n+2)}{6}x^3+.......$$  So we get $$nx=\frac{1}{3}$$ and $$\frac{nx(nx+x)}{2}=\frac{1}{3}\cdot \frac{3}{6}$$  We get $$\frac{1}{3}\left(\frac{1}{3}+x\right)=\frac{1}{3}\Rightarrow x=\frac{2}{3}$$  So we get $$n=\frac{1}{2}$$  So our series sum is $$(1-x)^{-n} = \left(1-\frac{2}{3}\right)^{-\frac{1}{2}} = \sqrt{3}$$  Although I know that this is the simplest proof, can we solve it any other way someting like defining $a_{n}$ and then use Telescopic sum.  Thanks. Can I, as a reviewer, tell authors to get a native English speaker to proofread their paper? I am reviewing a paper for possible publication in a respected journal. The English in the paper is very poor. The authors are clearly not native English speakers. I want to write something to the effect of the following in my review.   I advise the authors to find a native English speaker to proofread the manuscript.    My question: Is this appropriate in a review?  On one hand, I think it is good, constructive advice. The paper would be significantly clearer if someone spent a few hours helping them fix it up. I can try to help them through reviewer comments, but it would be much easier if someone could help them in person. The authors are located in a western English-speaking country, so they should be able to find someone.  On the other hand, I don't want to be "the mean reviewer." I understand that English can be difficult to master for immigrants. Perhaps there is a more diplomatic way of saying this. I'm using a docker image as a base for my own development that adds the jessie backports repository in its Dockerfile and uses that to install a dependency. This image uses the following command to add the repository:  echo "deb http://ftp.debian.org/debian jessie-backports main" &gt;&gt; /etc/apt/sources.list   The problem is that fetching packages from the backports repository now  fails with the following error (this used to work previously):  W: Failed to fetch http://ftp.debian.org/debian/dists/jessie-backports/main/binary-amd64/Packages 404  Not Found  W: Failed to fetch http://deb.debian.org/debian/dists/jessie-updates/main/binary-amd64/Packages  404  Not Found   I looked on that server, and those paths are indeed not present there.  I tried to figure out on the Debian backports site whether this particular repository should still be available, and I didn't find any indication that this was deprecated or something like that.  Is this a temporary issue with the repository, or is the jessie-backports repository not available anymore? And if this is not a temporary issue, what options do I have to use this or an equivalent repository without upgrading to the newer Debian stable version? Is it possible to redirect a command's output to cd? For example, I searched for a directory using locate and got the path to it. Now, instead of writing a cd path, can I redirect the locate output to cd?  I tried this:  $ locate Descargas | grep Descargas$ /home/oliver/Descargas $ locate Descargas | grep Descargas$ | cd $ locate Descargas | grep Descargas$ &gt; cd $ locate Descargas | grep Descargas$ &lt; cd /home/oliver/Descargas $    No luck. This probably isn't particularly useful, but I'm curious. When should I use a struct rather than a class in C#?