The play/pause and backward and forward buttons on my MacBook are not working as they should. When I press the play/pause button, nothing happens or it quickly pauses and plays again. Backward/Forward buttons are skipping previous/next song and play the second one in order.  I don't have Google Play Music installed. I've also reset SMC but it didn't help.   Anyone know what could be a possible problem?  I'm using macOS High Sierra.
I am being driven crazy by the fact that my media keys aren't working for iTunes. Such a pain! How can I fix this? I've tried the whole Chrome Extensions thing, that being I deleted all my extensions. Still, nothing has fixed this. Thanks to all who reply!
Why use sucrose rather than glucose in an injectable vaccine? Connect Tikz nodes via two parallel arrows I am just starting to learn using Tikz and am a little lost within its seemingly infinite amount of options and possibilities.  What I am trying to do is visualize a few Matlab function interaction (which one calls which one, what is the in- and output). Since there are only about six subroutines, I place each one manually as a node. This is an example:  \documentclass{article} \usepackage{tikz} \usetikzlibrary{shapes,positioning}  \begin{document}  \begin{tikzpicture}[auto] \node           [rounded rectangle,draw]        (node1)     {Node 1}; \coordinate [above=of node1]                                (input); \node           [rounded rectangle,draw]    at  (-10:6cm) (node2)       {Node 2}; \draw           [-&gt;,very thick]             ([xshift=0.1cm]  input.south)  --                  node {right}                ([xshift=0.1cm]  node1.north); \draw           [-&gt;,very thick]             ([xshift=-0.1cm] node1.north) --                  node {left}                 ([xshift=-0.1cm] input.south); \draw                                            (node1) -- (node2);  \end{tikzpicture}  \end{document}     Now I would like to apply these double in/out arrows I (probably pretty awkwardly) created using xshift to all node connections, so in this example also for the connection between Node 1 and Node 2. Ideally, the space between these two arrows would be the same, independant of their angle and they would nicely connect to the outer line of the nodes. Any idea how I could achieve this? Similar questions I have found only used rectangle and orthogonal lines. Break a loop animation (Make Cyclic) to start a new one I've used the 'Make Cyclic' to loop these keyframes (image below). So, I want to break the loop at a certain time to do a new animation (insert another kf to do a different thing than the loop does). Any help how to do this?    Thanks in advance! $\hbar \rightarrow 0$ in quantum mechanics We often see a limit $\hbar \rightarrow 0$ in quantum mechanics and sometimes it's related with symmetry breaking. Can someone briefly write the story behind this limit? Is the change in the Lagrangian always a total derivative for symmetry transformations of the action? Let $\Omega\subset\mathbb R^n$ and consider an arbitrary functional $$ S\colon C^k(\Omega)\to\mathbb R $$ that is local, $$ \phi\overset S\mapsto \int_\Omega L(\phi,D\phi,\dots,D^k\phi) $$ for $L$ some $n$-form taking values in the $k$-jet space $J^k\phi$. We may call $S$ the action functional, and $L$ its associated Lagrangian (although we do not assume that $\delta S[\phi]=0$, i.e., we work off-shell).  There are two notions of a symmetry that are typically discussed:   Lagrangian symmetries, that is, transformations of the form $\phi\to\phi'$ that satisfy $$ L-L'=\mathrm d\Theta $$ for some $(n-1)$-form $\Theta$, and where $L'(J^k\phi)=L(J^k\phi')$. Action symmetries, that is, transformations of the form $\phi\to\phi'$ that satisfy $$ S-S'=0 $$ where $S'[\phi]=S[\phi']$.   If we assume that the boundary conditions are such that $\Theta|_{\partial\Omega}=0$, then it is clear that Lagrangian symmetries are also action symmetries.  If we assume that $\Omega$ is "nice-enough" (e.g. star-shaped) then I believe that any action symmetry is also a Lagrangian symmetry, although I would like to have a more precise statement about this fact. In other words, my question is     Are these two notions of symmetry equivalent? Under what conditions?   Moreover, how much can we weaken the assumptions? For example, can we take $\Omega$ to be simply-connected instead of star-shaped? Can we take $\phi$ to only have weak derivatives instead of strong derivatives? On my Toshiba Encore 8 Tablet I noticed that the CPU usage is very high. In Taskmgr / ProcessExplorer, I can see that OneDriveSetup.exe is hogging 1 CPU cores heavily for hours.    How an I solve this hang and finish the OneDrive Update? I’m a big fan of ampersands (possibly too much …) and I’d like to replace all mentions of “et al.” (included in citations) by \&amp; al. – both in the main text (I use natbib citations of the form [Author1 et al., 1999]), and in the actual bibliography?  How can I do that, considering that BibTeX is inserting the words for me, and I have no control over the text? Preferably, I’d like to do this without creating my own bibliography style sheet (since I want to make this work regardless of the actual BibTeX style that is used), but if anyone can tell me how I need to edit the style sheet file, that would be fine as well (makebst doesn’t seem to offer an option for this …). How do I get a bigger static scrollbar (aka normal scrollbar)? With the new  and the upcoming release of  film, JK Rowling has been awesome and given us new writing on the .  In the introduction it is stated that there are eleven established/registered schools. There are writings for six of them. I don't think we need a new writing for Hogwarts... so that means seven have been located and defined.   Hogwarts School of Witchcraft and Wizardry - Great Britain  - France  - Northern Europe (possibly Estonia, Latvia, or Belarus)  - Japan  - Africa (possibly Congo/DRC)  - Brazil  - United States   Do we know anything of possible location or names of the other four schools? I know Koldovstoretz was mentioned as school in Russia, but is that still canon?   Koldovstoretz - Russia (maybe depending on current canon)   The final three are my guesses based on the population and geography on the world.   Name Unknown - China (based on population) Name Unknown - India (based on population) Name Unknown - Australia (based on geography)   Related: If $f:\mathbb R \to \mathbb R$ satisfies $f'(x) <L$ for some $L<1$, then $f$ has a unique fixed point Assume that $f: \mathbb{R} \rightarrow \mathbb{R}$  is differentiable.  If there exists an $L&lt;1$ such that for each $x \in \mathbb{R}$, $f'(x)&lt;L$, prove that there exists a unique point $x$ such that $f(x)=x$.  So far I have that where I fixed $a$ to be zero and came up with three cases to show existence for  $f(0) = 0$, $f(0) &lt; 0$, and $f(0) &gt; 0$  $f(0)=0$ was fairly trivial following from the mean value theorem but the other two cases I was only able to eliminate half of the possible fixed points by contradiction and I need help showing it explicitly.  Edit as to avoid confusion here is the work I have garnished so far:  From the mean value theorem it follows for some arbitrary $a,b \in \mathbb{R}$ and $a\neq b$ that there exists a point $c$ such that $a&lt;c&lt;b$ or $b&lt;c&lt;a$ then implies that $\frac{f(b)-f(a)}{b-a}=f'(c)$ and this is because it is differentiable on $\mathbb{R}$ and, by convention, is also continuous on $\mathbb{R}$ as well.  Then the result of $\dfrac{f(b)-f(a)}{b-a}=f'(c)$ then follows for $L&lt;1$ such that $\forall x \in \mathbb{R}$ means $f'(x)&lt;1$ from our hypothesis. Which then follows  (*) $\dfrac{f(b)-f(a)}{b-a}=f'(c)&lt;L&lt;1 \Rightarrow f(b)-f(a)&lt;L(b-a)&lt;b-a$  Now without loss of generality choose $a=0$ and let $b$ be some arbitrary value in $\mathbb{R}$ then there are three cases that need to be considered for the value of $f(a)$:  (i) $f(0) = 0$, (ii) $f(0) &lt; 0$, (iii) $f(0) &gt; 0$  (i) For $f(0)=0$   Then $0$ is a fixed point of point of $f(x)$ and it follows from (*) that if $f(0)=a=0$ then $f(b)-f(0)=f(b)&lt;Lb&lt;b$ which shows that $f(b)&lt;b$ thus shows that for any arbitrary value $b\in \mathbb{R}$ that no $f(b)=b$ thus shows that $0$ is the only fixed point if $f(0)=0$  (ii) For $f(0)&lt;0$  Suppose there exists a fixed point $d&gt;0$ then:  $\frac{f(d)-f(0)}{d}&lt;L&lt;1 \Rightarrow d-f(0)&lt; dL&lt;d \Rightarrow -f(0)&lt;d(L-1)&lt;0\Rightarrow 0&lt;-d(L-1)&lt;f(0)$ but this contradicts that $f(0)&lt;0$  thus no other fixed point exists if $d&gt;0$ when $f(0)&lt;0$  (iii) For $f(0)&gt;0$ How to fix "404 Not Found" crawl errors reported by Google in Search Console I was checking on Google webmaster tools for my blog site to see if there's any indication on why my blog traffic decreased to half in one day and i saw 43 Not Found crawl errors and 5 in Sitemap Not Found errors.   The 5 Not Found errors in Sitemap were the links to categories. I guess I renamed categories that's why Google can't find the links.   As for the 43 other Not Found errors, I see blog post titles that contain ' or . For example "McDonald's" or "O.N.E."  They weren't found by Google crawler.   There is also a blog post with /CachedYou at the end and a blog post with /www.example.com attached at the end.  They weren't found by Google crawlers either.   How do I correct those Not Found Errors? Novel about a teleportation device and a con artist alien I read two (maybe three) books about a protagonist who communicates with an alien who provides the instructions on how to create a device to teleport. The device is flawed in that it purposefully uses more energy (much more) by taking it from the rotation of the Earth.  The main character and two others continue to fight, commit intrigue, etc. The alien then uses them to recruit other races to do the same thing. Is my US visa still valid after change in name? I'm a Malawian national and I got US Visa years back.  Recently, due to some reasons, I had to get my first name partially changed on my passport. I have got an affidavit certificate stating the reason and proof.  Since the visa on my old passport has still not expired, but there is a difference in first name, will I face any problem? Is there a way to assign a value to a variable, that value which we get in terminal by writing any command?  Example command: sensors  From that we get CPU temperature. How can I assign this value to a temp_cpu variable? Double rm verification in zsh When I do a rm * in zsh, I get something like this:  2014-06-08 10:14:23 $ rm * zsh: sure you want to delete all the files in /home/assay/assay/log [yn]? y rm: remove regular file `development.log'? y   First zsh asks me if I am sure I want to delete all, and then rm asks for for each specific file.  How can I just have the zsh verification? converge and converge absolutely of a series $f(x)$ is a continuos fuction in $[0, 1]$ and differentiable twice on $0$.  $U_n=(-1)^{n}f(\frac{1}{n})$. I need to prove that:   $1.$if $\sum_{n=1}^\infty U_n$ converge then $f(0)=0$.  $2.$if $f(0)=f'(0)=0$ then $\sum_{n=1}^\infty U_n$ converge absolutely.  Now, from the detail that $f(x)$ is differentiable twice on $0$ I think I need to write $f(1/n)$ with Maclaurin series with 2 degree but it doesn't work very nice. can you guide me please? thanks! When I try to print a Unicode string in a Windows console, I get an error . UnicodeEncodeError: 'charmap' codec can't encode character .... I assume this is because the Windows console does not accept Unicode-only characters. What's the best way around this? Is there any way I can make Python automatically print a ? instead of failing in this situation? Edit:  I'm using Python 2.5.  Note: @LasseV.Karlsen answer with the checkmark is sort of outdated (from 2008). Please use the solutions/answers/suggestions below with care!!  is more relevant as of today (6 Jan 2016). Why does bash show 'Terminated' after killing a process? Here is the behaviour I want to understand:  $ ps   PID TTY           TIME CMD   392 ttys000    0:00.20 -bash  4268 ttys000    0:00.00 xargs $ kill 4268 $ ps   PID TTY           TIME CMD   392 ttys000    0:00.20 -bash [1]+  Terminated: 15          xargs $ ps   PID TTY           TIME CMD   392 ttys000    0:00.21 -bash   Why does it show the [1]+  Terminated: 15          xargs after I kill a process, instead of just not showing it as it was just killed?  I'm using bash on Mac OS X 10.7.5. I've followed this tutorial to install Ubuntu 15.10:    After restarting my computer I got to the grub menu and chose Ubuntu. Shortly after that I got this error:  /run/lvm/lvmetad.socket: connect failed: No such file or directory WARNING: Failed to connect to lvmetad. Falling back to internal scanning.   These messages keep adding up on a black screen every second. After a while,  I get access to the initramfs ash console.  what am I doing wrong? How to create a bootable Ubuntu USB flash drive from terminal? Is there any way to create a bootable Ubuntu USB flash drive from the terminal without using any third-party applications like , , ,  etc.  I tried to create a bootable Ubuntu flash drive with dd method,  sudo umount /dev/sdb sudo dd if=/path/to/ubuntu.iso of=/dev/sdb bs=1M   It creates files on the USB disk, but when I try to boot the USB disk it shows an Operating System Not Found error.