Upgrade to Firefox 9 crazy dependencies?

Question: Today I logged into my Ubuntu 10.04 remote dekstop machine for the first time in a while. I noticed that Firefox 3.6 would be upgraded to Firefox 9. I typed "sudo aptitude safe-upgrade" at the terminal and found out that the upgrade would require 430 MB of disk space. There is a kernel update among, but I still think that 430 MB is very much. The list of dependencies required is very long:
apturl-kde{a} exiv2{a} firefox-locale-en{a} gdebi-core{a} gdebi-kde{a} hal{a}hal-info{a} icoutils{a} install-package{a} kdebase-runtime{a} kdebase-runtime-data{a}    kdelibs-bin{a} kdelibs5{a} kdelibs5-data{a} kdepimlibs-data{a} kdepimlibs5{a} kdesudo{a} kpackagekit{a} kubuntu-debug-installer{a} libakonadiprivate1{a} libattica0{a} libboost-program-options1.40.0{a} libclucene0ldbl{a} libdbusmenu-qt2{a} libexiv2-6{a} libgif4{a}
libgpgme11{a} libilmbase6{a} libiodbc2{a} libopenexr6{a} libpackagekit-glib2-12{a} libpackagekit-qt-12{a} libphonon4{a} libplasma3{a} libpolkit-qt-1-0{a} libpth20{a} libqca2{a} libqt4-assistant{a} libqt4-dbus{a} libqt4-designer{a} libqt4-help{a} libqt4-qt3support{a} libqt4-script{a} libqt4-scripttools{a} libqt4-sql{a} libqt4-sql-sqlite{a}
libqt4-svg{a} libqt4-test{a} libqt4-webkit{a} libqt4-xml{a} libqt4-xmlpatterns{a} libraptor1{a} librasqal2{a} librdf0{a} libsoprano4{a} libssh-4{a} libstreamanalyzer0{a} libstreams0{a} oxygen-icon-theme{a} packagekit{a} packagekit-backend-apt{a} phonon{a} phonon-backend-null{a} plasma-scriptengine-javascript{a} polkit-kde-1{a} python-kde4{a} python-packagekit{a} python-qt4{a} python-sip{a} shared-desktop-ontologies{a} smartdimmer{a} software-properties-kde{a} soprano-daemon{a} ttf-dejavu{a} ttf-dejavu-extra{a} update-manager-kde{a} virtuoso-nepomuk{a} x11-xserver-utils{a} xdg-utils{a} xul-ext-ubufox{a}

It seems crazy to me that so many KDE an QT packages are required to upgrade Firefox, if I wanted them I had choosed Kubuntu instead of Ubuntu. It also seems weird to me that hal and hal-info are going to be installed, I thought that almost every Linux disto was going away from hal because it is big mess, but now it is required?
Can anybody with an Ubuntu 10.04 installation confirm that they had the same massive amount of dependencies when they upgraded to Firefox 9, or is there been some sort of dependency mistake in my cas?

To include more information in my question, I tried to uninstall Firefox and then upgrade all the other packages, this was about 130 MB, then I tried to install Firefox again, but now only 31 MB was required.
The package installed without any problems and now my remote desktop has Firefox 9 without any KDE or QT dependencies. I think that pages load more smooth and quicker in Firefox 9, so this is great.
Comment: Can you see what the normal update manager does and add that information to your question?
Answer: Upgrades on Kubuntu might have a lot of dependencies .Firefox needs only some of them of them
Such as the xul-ext-ubufox. But it is probably because you havent updated in a while.
Answer: You may just have a lot of updates to do, since you said you hadn't logged in for a while. It's not necessarily all for Firefox.


What are some good exercises to work the forearms?

Question: My husband and I have both been lifting dumbbells in an attempt to build some muscle. We feel like we're hitting our upper arms pretty well, but not the lower arms. What are some good exercises to work the forearms?
Answer: Lifts in no particular order:

Wrist Curls
Reverse Wrist Curls
Farmer's Walk
Wrist Roller
Reverse Curls (these interject the outside of the forearm almost as much as the bicep)

Other things that help:

When running, do so with tennis balls in your hand so you force yourself to grip the entire time.  The gain is nominal, but it is another chance to work your forearms while exercising
When at work, periodically squeeze on a stress or tennis ball when not typing/writing, or otherwise using your hands.
When lifting, make sure to squeeze the bar/weight as much as possible, no matter what lift you are doing.  If it's a machine, grip the handle as hard as possible.  This forces you to tighten not only your hands/formarms to work them, but also makes you tighten the rest of your body.  There's really no such thing as a lift that only works parts of your body - if you are doing them correctly.
Answer: Wrist curls do wonders. One exercise is like a preacher curl, but instead of moving your entire forearm, just move your hands at the wrist. Another is just the opposite, with your palms facing down and hand bending up.
In reality, though, the forearms are hit by most exercises that hit the biceps and triceps. Even if you don't think you're working them, you are in reality.
Answer: A lot of development will come from just working with progressively bigger weights, but if you really want something specific, check this list out.
Answer: I personally would not recommend wrist curls, which work lower arms, but I know that chin ups, pull ups, bicep curls, and even simply grasping dumbbells will build forearm muscles.


Mouse cursor invisible after installing Parallel Tools

Question: After installing Parallel tools, the mouse pointer is not visible but works if I click. Can I re-enable it via Terminal?
Comment: I faced this issue in Parallels when I installed ElementaryOS Loki. Let me know if you are doing installation on Parallels then I can help you. Most people complained about mouse not showing or working when installing on Parallels
Comment: Yes. The mouse disappears until the installation of parallel tools. :-/ Can I restore the original driver of elementary??
Answer: So here is the solution if you are using Parallels to install ElementaryOS Loki
There is no Parallel Tools driver issue. It is just Boot Flag setting.
After installation of Parallel Tools, shut down and don't start Loki. Go to
Settings --> Hardware --> Boot Order
There you would see Advanced Settings, where you can set the boot flags. Type there
devices.usb.mouse=1

And now start your Virtual Machine, it would work
if 1 doesn't work then try 0. But for me in Parallels, 1 worked
Comment: the `devices.usb.mouse=1` worked for me, a value of `0` did not.


About atheism and secularism and what exactly they are

Question: If Atheism and secularism and Materialism are not belief systems what are they? They are not facts ; nothing one way or the other has been proven. They are more like a set of assumptions and beliefs and opinions but all together they are not to be considered a belief system. If you call them a world view this is still like a belief system ; using a set of beliefs and opinions and personal interpretations of some facts that all lead to 'handling' various important philosophical questions. Some of these questions if left unanswered are VERY disquiting when unresolved. So if Atheism , secularism and Materialism are not belief systems WHAT ARE THEY?
Comment: @Dave I've seen these words used with varying definitions.  Is an atheist someone who doesn't believe in God, or someone who believes there is no God?  Does a materialist reject the idea of telepathy outright or just considers the evidence far from convincing, and figures that if it exists, it's subject to laws of nature?  Is a secular society one where all religions are welcome, or one where religion is disdained?
Comment: Is there a particular work (or other context) where the meanings of these terms are unclear?
Answer: They are belief systems. Any conjecture on a situation that has no proven answer is a belief. No exceptions. Nobody knows for certain the meaning or lack of meaning in the universe and thus any opinion on the matter is exactly that, opinion, belief, idea, or philosophy.
Comment: A set can have one element.  Various fundamentalisms that proceed from single belief are still belief systems.
Comment: a belief is different from a belief system.
Comment: That is the downfall where those of realistic beliefs succumb to ignorance. I am secular but I can not consider myself an atheist because I realize that every speculation on life or death is impossible to prove. Therefore, they are all beliefs, each one as valid as the next, whether it be the Christian God, a flying bowl of spaghetti, or nothing at all.
Comment: Is the belief it is absolutely impossible to ever prove there is an after-life or not itself a belief or a fact? Also one can't say one 'set' of beliefs is as valid as the next as many beliefs 'contradict' one another; i.e., the Mormons believe only they will 'make it' to an after-life. You could call this an 'exclusionary' belief system. The Jahovah's Witness is exclusionary, so is 7 Day Adventists , and the Christian Faith. Most Faiths are exclusionary except the Hindus and the Ba'hai Faith.  All religious beliefs can not be correct at the same time.
Comment: I noticed people who are atheistic, materialistic or secular do not want to consider their views as belief systems partly because they want to consider their 'world views' as 'separate' from religion or beliefs in the 'supernatural'. As such they feel their beliefs are more 'grounded' in 'reality' and have a 'special connection' to what is 'real'; and therefore anyone who is 'religious' can't hold a candle to their arguments. By 'being separate' from any religious belief they assume their views are superior. This is why they don't want to think of atheism as a belief system or a religion.
Comment: A quibble. It is very dangerous to say ';nobody knows' and it is only a conjectural belief.  . .
Answer: In the absence of further context:

Atheism and materialism (physicalism) are individual beliefs about the world.
Secularism is a belief system, i.e. group of inter-related beliefs about the world.

Quick google results:

atheism: Most inclusively, atheism is the absence of belief that any deities exist (definition that pops up on Google)
materialism: the doctrine that nothing exists except matter and its movements and modifications (defintion that pops up on Google)
secularism: Secularism is a code of duty... (quote from George Jacob Holyoake via

Thus, they are variously, (absence of) belief, a doctrine, and a code of duty.
Secularism (as used by Secular Humanists) involves a whole series of beliefs about what should (and shouldn't) be considered when trying to identify moral goods.  Thus, at many levels of discussion, it would be worth considering secularism as an aggregate belief system (as opposed to a more or less atomic belief).
For materialism, the case that it is an aggregate belief system, as opposed to a single belief is harder to make.  It's pretty much just that the material world is all that there is.  Although one can poke at it to try to clarify what exactly any given materialist philosophy means by material, world, or examine any of the various consequences of adopting this belief, but the term materialism itself ends up referring to, essentially, a singular belief.
Atheism is in the same boat as materialism: it is essentially, an atomic belief.  Again, if you get into it, you might be able to identify aspects of it that are arguably component sub-beliefs, but at the level of general discussion, it fits nicely into the category of being a belief.
In the absence of any context that indicates that you're going to drill into the details, the first two are individual beliefs, while the third is a network of inter-related beliefs.  I keep hedging about context because I cannot rule out the possibility that there are situations where would would want, and be able to, break materialism or atheism into component sub-beliefs. However,I cannot think of a specific context where this is breaking down is necessary or useful, so the descriptions here should apply in general.
It's also worth pointing out, that no one of these items, by itself, provides resolution to all (or even most of) the "disquieting" questions.
Comment: @gnasher729 'An absence of belief' would not have a version with less belief, and atheism has agnosticism as a weaker fallback.  So the Google definition is just wrong.
Comment: You should have stayed with the Google definition that atheism is an _absence of belief_. You can add to that a belief that the subject of religion is quite irrelevant.
Comment: Is Atheism the BELIEF  that an absense of belief in ANY theistic philosophies is the 'best' wisest option?
Comment: @user128932 Informally, that statement might be okay; but speaking more formally there are two issues:  the rejection of theistic philosophies is a logical consequence of taking the atheistic stance "No gods exists", but "atheism" and "rejecting all theistic philosophies" are not the same thing (c.f. hard agnosticism).   Second, your use of term "best wisest" in your statement injects an undefined utility measure (wisestness?) into the discussion, which is not necessary for defining atheism.
Comment: @jobermark a weakened version of "absence of belief in X" is "allowing some degree of belief in X", i.e. agnosticism (about X in this case).
Comment: @Dave No.  You do not 'allow' belief, you have it or you do not have it.  Agnosticism is non-belief, atheism is certainty of the falsehood of a proposition, which is a belief.  Play what games you will, less is less.  Atheists want a definition of atheism that makes it seem to be the default position from which all others must be defended.  But that is just cheating.  The default position, across almost all cultures has been to have a religion with supernatural contents, and not atheism.
Comment: @jobermark what is your theory of belief where "You do not 'allow' belief, you have it or you do not have it"?  and how does that theory account for common-sense notions of certainty/uncertainty of belief? (if a mod sees this, it should probably be a link to an appropriate chat)
Comment: @Dave Uncertainty is about beliefs, not a part of them.  You can be uncertain whether you hold a belief, but beliefs themselves are all certain.  Even hard agnosticism is certain that needs no more certainty.  It is the same way probability is not about the nature of winning, it is about whether it will happen.  'Allowing' whom?  Yourself?  If you are 'allowing' me, try to stop.  The framing of 'allowing' belief is to me proof this is really a moral and not an ontological position.  I mean 'allowing' under what censure -- your *moral* disapproval.
Comment: @jobermark chat?
Comment: Let us [continue this discussion in chat](http://chat.stackexchange.com/rooms/17775/discussion-between-dave-and-jobermark).
Comment: @gnasher729 To be more precise, strong [atheism](http://en.wikipedia.org/wiki/Atheism) is *the belief that no deities exist*, weak atheism is the absence of belief one way or another.  The predominant use, certainly in formal philosophy, is the former (probably because the later proves very wishy-washy, as per the above debate).
Answer: I think calling atheism a "metaphysical position" might be the best term. It's general enough to capture beliefs and absence of beliefs.
Secularism, in the sense of beliefs about separation of church and state or things like that, might be more of a sociopolitical position.
Answer: It seems to me that atheism, like theism, is in and of itself a belief rather than a belief system — though, like theism, atheism is personal, subjective, and spectral, which is why both labels mean different things to different people.
For example, I personally believe there is no God.  This doesn't mean I'm certain about it: beliefs are, by definition, unprovable.  (Otherwise, they'd be facts, in which case faith — i.e., personal commitment to belief — would be gratuitous.)  It also doesn't mean I'm antitheistic.  I respect and support religion, since it provides significant benefits such as hope, comfort, strength, belonging, and structure to billions of people.  The only thing I'm "anti" about is disrespecting each others' personal, spiritual, existential boundaries.
Regarding belief vis-à-vis belief system as they apply to atheism (or theism), I believe beliefs beget belief systems.  Here, too, I can reference experience:  Once I admitted/accepted my belief, I recognized the need for a moral compass — a set of primary values to govern behavior, facilitate growth, and assist in considering conflicts.  Then, I realized the need to base those values on what I care about most of all in life:  how people treat each other.  So I chose the principal values of equality, respect, understanding, and coexistence.  They work well together in guiding me through life; thus, at least in my case, the belief, supporting values, corresponding worldview, and resulting behavioral code constitute a belief system.
Then again, "belief system" also means different things to different people:  e.g., whether or not it involves a group rather than an individual; whether it's formally codified; etc.
Please note that, as I see it, neither atheism nor theism is a moral position.  One can embrace either belief and, independently, choose one's personal moral code.  (In contrast, "morality" implies a much higher degree of subjectivity, encompassing both one's own perception and others' perceptions, any or all of which may irreconcilably disagree.)
As to secularism and materialism, I'm not sufficiently knowledgable to discuss either term.


IQ test puzzles - diagonal line shapes, curly line shapes

Question: What is correct answer for these two IQ puzzles and why?
Answer: These are effectively the same puzzle.

 Divide each image into 4 lines, preserve one half of them across rows and the other across columns.

Puzzle 4

 The top here has some lines flipped diagonally, which is strange.

Puzzle 10

Answer: Puzzle 4:

 D. Rotate bottom right about its centre by 90degrees, rotate top left. Except for the first row is in the wrong order. Otherwise F could be the right answer. But middle row to bottom row is switch top right, so definitely D.

Puzzle 10:

 C. By rows, vertical lines become inward semi-circles, which become outward semi-circles; by columns, the horizontal lines are transformed.
Answer: Puzzle 4

 D: Each picture is made of 4 diagonal lines arranged as 2×2. On the first transformation, one of them gets flipped. On the second transformation, the line that's to the opposite corner of the line that was flipped first gets flipped.

Puzzle 10

 C: The first transformation is the image "squeezed" by a specific pattern (two circles from the left and right), and the second transformation is the image "expanded" by the same pattern.
Comment: This explanation for 4 is correct!
Answer: Puzzle 4

 The answer is D. Explanation:
 Only red and green lines are toggling in the each row. Transformation always starting from the line pointing to the right. Position (top or bottom) doesn't matter. So, the line inclined to the right rotates to the left in the first step. It's causing both lines always inclined to the left in the middle column. In the next step the second line (opposite diagonally), rotates to the right. Thus, in the end of each row, red and green lines flip vice versa, comparing to the starting position - the right becomes pointing to the left and the left becomes pointing to the right.

Answer: Puzzle 4

 D - One segment is rotated each time from the first column in a row to the second. From the second to the third column, the segment directly opposite the previously rotated segment is then rotated to reflect the initial segment.

Puzzle 10:

 I think it is A. My reasoning behind this is that they are doing a series of inversions to get the next figure (row and columnwise). So by applying the same inversions to row 2 column 3 and row 3 column 2, we get the circle.
Answer: Puzzle 4:

 number of left-top to right-down lines
Comment: `A` would also fit in that case.
Answer: Puzzle 4. The answer is H.
Notice that 1,3 is the same as 1,1 except rotated 180°. Also 2,1 (the two right arrows), is the same as 2,3 (the two up arrows) except that it is rotated 90°. 2,2 also has it's partner at 3,1. So, all pairs are the same except that they may be rotated a multiple of 90°. So, what about the X at 3,2? It is it's own pair. What about the three lines at 1,2? There is no pair.
So the answer must be H.


What is the difference between stress and excitement?

Question: I was wondering if excitement is also bad for your body. I know it uses the same parts of the brain. And when i feel excited I don't want to eat and i get jittery. it is also the same with stress or anxiety.
Answer: Stress and excitement both activate the sympathetic nervous system, so they can feel very physically similar (high heart rates, etc.) The main difference is in higher-level brain processing, where stress is subjectively perceived as negative and excitement as positive. Interestingly, there is a study that proposes "anxiety reappraisal" in which you tell yourself you're excited instead of nervous, to facilitate management of high-stress situations. See popular press coverage here: http://nymag.com/scienceofus/2016/03/youre-excited-not-nervous-you-just-keep-telling-yourself-that.html and the original study by Alison Wood Brooks here: https://adobe99u.files.wordpress.com/2015/06/xge-a0035325.pdf
Answer: Although you do activate a lot of the same systems in both cases, I would think your biggest difference will be what else you activate when excited, which would be Dopamine, Oxytocin, Serotonin, Endorphins, etc.  When you are stressed you will actually release cortisol which will inhibit excretion of other feel good chemicals.  You may release the feel good ones when the stress has passed, depending on the type of stress (horrible daily grind of an awful job versus the stress of being chased by a hungry bear & getting away). http://www.thepositivepsychologypeople.com/habits-of-a-happy-brain/
Most stress people feel in the modern developed world is more of a long term nagging sort, versus the survival level sort.  That is also long & drawn out in such a cases, versus excitement, which in intense feeling, is generally rather brief.  You don't typically sustain the anxious level excitement that impacts eating, sleeping, etc longer term.  You can experience all those for a fair amount of time though when in love.  It would still then be coupled with positive chemicals versus the levels of cortisol & such experienced when instead it's negative feelings you are experiencing with similar side effects.
Comment: The term you're looking for for positive stress is eustress.


Which point mutations in proteins are OK, and which cause significant change?

Question: I heard that some point mutations in proteins are OK, like from alanine to glycine (I'm not sure, it's just an example), some will change the protein significantly. I want to understand deeper but don't know the right keyword. I have tried some but none of them works. Can you give me a good keyword to start searching? Thank you.
Comment: Try googling "tolerated amino acid changes."  The connection between amino acids, overall structure and function is complex, and not completely solvable.  People can make guesses based on similarity between different amino acids, and can make better ones by consulting the protein structure, if it's known, but it's not possible to predict with total confidence that an amino acid change will be harmless or not.
Answer: There are twenty standard amino acids, and some of them are structurally/functionally similar to each other, such as aspartate and glutamate, or asparagine and glutamine, or glycine and alanine. In general, mutations that cause these amino acid switches don't change the function of the protein, but that's just a general rule - it also depends on where these amino acids are in the protein structure. These are called conservative mutations.
Answer: As others have said, although certain amino acid substitutions are considered to be conservative, the effect of a particular substitution will very much depend upon the context. Here are some examples:
gly>ala can change stability of glyceraldehyde-3-phosphate dehydrogenase
gly>ala mutations in a fungal glucoamylase increase thermostability
asp>glu in a lysosomal α-glucosidase is responsible for a glycogen storage disease
asn>gln will abolish glycosylation at NXS/T sites which can have effects on stability and secretion
ser>thr at the active site has profound effects upon catalytic activity of an alkaline phosphatase
Answer: I think you are referring to the concept of conserved substitution, which tends not to change the property/function (http://en.wikipedia.org/wiki/Sequence_alignment) of a protein although thats not necessarily true if the mutated AA (point mutation) changes a functional residue in an enzymatic domain such as GAP or kinase domains or even certain residues that are important for PP interactions such as tyrosine Y, which can become phosphorylated and thats important at times for its interaction with other proteins or the activation/inactivation status of a protein such as receptor tyrosine kinases (http://en.wikipedia.org/wiki/Receptor_tyrosine_kinase). But in most cases it depends where the AA is and the role of the AA. For example two AA can have the same charge/polarity but if their sizes are considerably different, then that could interfere with the way protein folds (conformational changes) and end up affecting its function. So AA substitution and its effects is not necessarily straight forward and its very much dependent on other factors!


Rollback delete of Tridion item

Question: I know I can use Version History to rollback a change to a Tridion item.  What if I delete that item and then want to rollback the delete?  Can I do that?  If so how, since the item will be gone from the CME.
Answer: I am afraid that You can not do this. If you delete any item from Tridion, it is gone forever. The only solution that I can see is that you restore this item from the Previous backups of your Content Manager database. Now if you have changed a lot of data after the delete then an alternate approach that you can follow is as below:

Take a back up of your existing Content Manager DB
Restore the older version of Content Manager DB which have the deleted version of the item
Use Content Porter Tool to create an export package of this deleted Item
Revert to the latest version of Content Manager DB by restoring the backup of your Latest Content Manager DB
Again use the Content Porter Tool to import the package you previously created containing the deleted item
Comment: some of the reasoning behind the Delete==Gone decision: you are only able to delete an item which is not (or no longer) in use, so that item has become less important to protect. Another reason is that SDL Tridion is a CMS and not a data warehouse, if all versions of all items (including deleted ones) would be kept, your database would become unmanagebly large.
Comment: You can proactively take Content Porter packages to reduce the database restore parts. In practice, I've moved items to "archive" or dated folders rather than delete them if I might need them later. The input source and rendered content seems to last forever as well (e.g. original request, versions on Dev or Test servers, and archived pages).

Rollback delete of Tridion item


What is an ABI and why is it needed to interact with contracts?

Question: ABI is referenced in many places including the official Ethereum website. What is an ABI and why is it necessary to use?
Comment: The ABI of a smart contract gives a contract the ability to communicate and interact with external applications and other smart contracts. If you're using tooling like Hardhat / Truffle, the contract ABI is automatically generated for you. More dets if you're interested: https://www.alchemy.com/overviews/what-is-an-abi-of-a-smart-contract-examples-and-usage
Answer: The ABI, Application Binary Interface, is basically how you call functions in a contract and get data back.

An ABI
determines such details as how functions are called and in which
binary format information should be passed from one program component
to the next...

An Ethereum smart contract is bytecode deployed on the Ethereum blockchain.  There could be several functions in a contract.  An ABI is necessary so that you can specify which function in the contract to invoke, as well as get a guarantee that the function will return data in the format you are expecting.
From Ethereum's ABI specification, an example:
contract Foo {
  function bar(real[2] xy) {}
  function baz(uint32 x, bool y) returns (bool r) { r = x > 32 || y; }
  function sam(bytes name, bool z, uint[] data) {}
}

If we wanted to call baz with the parameters 69 and true, we would pass 68 bytes in total, which can be broken down into:

0xcdcd77c0: the Function Selector. This is derived as the first 4 bytes of the
Keccak-256 hash of the ASCII form of the Function Signature baz(uint32,bool).
0x0000000000000000000000000000000000000000000000000000000000000045:
the first parameter, a uint32 value 69 padded to 32 bytes
0x0000000000000000000000000000000000000000000000000000000000000001:
the second parameter - boolean true, padded to 32 bytes

The 68 bytes is what would be specified in the data field of a transaction, also called calldata: a security note on that is here. (To summarise, be careful what you put in the data field, because it can have unintended, possibly malicious side-effects when passing it to the calling contract.)
To avoid a common pitfall when deriving the Function Selector, the canonical types must be used, for example uint256 instead of uint.
Here is an example in Solidity of computing a Function Selector for sam above:
bytes4(keccak256("sam(bytes,bool,uint256[])")

Using a higher-level library such as web3.js abstracts most of these details, but the ABI in JSON format still needs to be provided to web3.js.
Note: the ABI is an abstraction that is not part of the core Ethereum protocol.  Anyone can define their own ABI for their contracts (starting example), and any callers of such contracts would have to comply with that ABI to get meaningful results.  However, it is simpler for all developers to use current compilers (example Solidity) and libraries (example web3.js, ethers.js) which all comply with the ABI above.
Comment: @hmijail https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI/66cd4e287f114d790e2a3536b2f889e058dd6d74 is the first commit on Github. Prior documentation may have been on an etherpad. To get things working, the early developers needed an ABI. The history is probably similar to how https://en.wikipedia.org/wiki/Comparison_of_executable_file_formats first developed.
Comment: what is the sam command part of the bytes4(sha3("sam(bytes,bool,uint256[])")
Comment: @FightFireWithFire Your comment is unclear.
Comment: The point about "this" ABI not being part of the Yellow Paper and anyone being able to define "an" ABI is really interesting/important (and kinda shocking, to someone like me coming from the world of CPU/OS ABIs). Would be nice then to have some reference/history on where did this ABI come from and why is everyone standardizing on it. Is maybe everything so clear-cut that there is no reason to have different ABIs?
Comment: What do you mean Solidity, Serpent, and Web3.js comply with the aforementioned ABI? Are ABI's language-specific?
Comment: @KennethWorden I edited the last sentence and is it clearer? Here's another attempt:, someone may think that a Function Selector should be longer than 4 bytes: they can write their contract that way but would not be able to use existing compilers (without modifying them), and users of that contract would need be able to use existing libraries as they are.
Answer: ABI stands for application binary interface.
In general, an ABI is the interface between two program modules, one of which is often at the level of machine code. The interface is the de facto method for encoding/decoding data into/out of the machine code.
In Ethereum, it's basically how you can encode Solidity contract calls for the EVM and, backwards, how to read the data out of transactions.
Answer: Contract Defintion: Formal definition in high-level code (e.g. solidity).
Compiled Contract: The contract converted to byte-code to run on the Ethereum Virtual Machine (EVM), adhering to the specification. Note the function names and input parameters are hashed during compilation. Therefore, for another account to call a function, it must first be given the function name and arguments - hence the ABI.
Application Binary Interface - ABI: A list of the contract's functions and arguments (in JSON1 format). An account wishing to use a smart contract's function uses the ABI to hash the function definition, so it can create the EVM bytecode required to call the function. This is then included in the data field, Td, of a transaction and interpreted by the EVM with the code at the target account (the address of the contract).

1Use of JSON is a de-facto standard; it's not in the formal spec but changing it would result in a need to amend many of the tools.
Answer: think of "ABI" as an "API" at a low level.
Think of it as the compiled version of an API (or as an API on the low  level). As you know the contracts are stored as bytecodes in a binary format into the blockchain under a specific address. No one understands binary, so the ABI  defines the structures and methods that you will use to interact with that binary contract (just like the API did), only on a lower level. The ABI indicates to the caller the needed information (functions signatures and variables declarations) to encode a meaningful(understood by the VM) call to the bytecode(contract).
additional info "from the official doc"

An Application Binary Interface (ABI) is intended to serve as the de
  facto method for encoding & decoding data into & out of transactions

.

We assert that all contracts will have the interface definitions of
  any contracts they call available at compile-time.
Answer: In case you want to use a simple online tool to encode parameters you could use https://abi.hashex.org
You insert the abi code to automatically parse parameters types or just enter them manually. In Function type selector constructor should be picked.
Here is an example, at the bottom are abi-encoded parameters that you enter in etherscan.io constructor parameters field input.
Answer: I was having a terribly hard time understanding the why part of this question myself, so I'd like to add one thing thanks to this excellent answer:
"How these bytes are interpreted into structured data is up to the program and thus up to the programming language used. In order to make it possible for two programs written in different programming languages to call each other, the compilers of such languages should implement the serialization and deserialization of data in the same way, i.e. they should implement the ABI specification, but they do not have to."
tl;dr a contract written in Solidity can interact with a contract written in Viper or Bamboo because they all implement and adhere to the ABI specification.
Answer: Just copy this json. This is contract ABI
Answer: ABI (Application Binary Interface) in the context of computer science is an interface between two program modules, often between operating systems and user programs.
EVM (Ethereum Virtual Machine) is the core component of the Ethereum network, and smart contract is pieces of code stored on the Ethereum blockchain which are executed on EVM. Smart contracts written in high-level languages like Solidity or Vyper need to be compiled in EVM executable bytecode; when a smart contract is deployed, this bytecode is stored on the blockchain and is associated with an address. For Ethereum and EVM, a smart contract is just this sequence of bytecode. To access functions defined in high-level languages, users need to translate names and arguments into byte representations for byte code to work with it. To interpret the bytes sent in response, users need to convert back to the tuple of return values defined in higher-level languages. Languages that compile for the EVM maintain strict conventions about these conversions, but in order to perform them, one must know the precise names and types associated with the operations. The ABI documents these names and types precisely, easily parseable format, doing translations between human-intended method calls and smart-contract operations discoverable and reliable.
It is very similar to API (Application Program Interface), a human-readable representation of a code's interface. ABI defines the methods and structures used to interact with the binary contract, just like API does but on a lower-level. The ABI indicates the caller of the function to encode the needed information like function signatures and variable declarations in a format that the EVM can understand to call that function in bytecode; this is called ABI encoding. ABI encoding is mostly automated, taken care of by compilers like REMIX or wallets interacting with the blockchain. Contract ABI is represented in JSON format. There are clear specifications of how to encode and decode a contract ABI.
Source
Answer: An ABI is like others said the Application Binary Interface - it's a lower level interface but it doesn't have to be inaccessible to programmers, for instance on linux: /sys/bus/usb/devices/.../power/persist is an example of an ABI. You can access many other Linux ABI's via /sys/bus/
See: https://www.kernel.org/doc/Documentation/ABI/
Answer: Introduction
The Application Binary Interface (ABI) of a smart contract gives a contract the ability to communicate and interact with external applications and other smart contracts. Receiving data from external sources can be critical for completing the goals of the application and the user.
In traditional web development, conversations about data happen between applications and servers through API's (Application Program Interface). Servers act as centralized sources of information that feed data to application by request.
On a blockchain, no such centralization of data exists.  Nodes essentially act as servers and smart contracts are on chain "hosted" functions.  Applications outside of the blockchain (and other smart contracts) need a way to communicate with smart contracts that are on-chain. This is where ABI comes into play.

Why ABI?
Before going into more details about what ABI is, it is good to understand why we have it.
Smart contracts are the core applications of the EVM (Ethereum Virtual Machine). The purpose of smart contracts is to execute transactions when certain conditions defined in the contract are met. These conditions can be events both on or off-chain. Smart contracts are written in high-level languages like Solidity but they are stored on the EVM  as executable bytecode, which is in binary format.
Source: https://hackernoon.com/hn-images/1*Sz1a7G2pQ62UnkHoieve4w.jpeg
Since this bytecode is not human readable, it requires interpretation to be understood. ABI allows anyone writing a smart contract to be able to communicate between a web application written in a high-level language like Javascript and the bytecode that the EVM understands.

What is an ABI?
Like its Web2 cousin, the API, ABI acts as a function selector, defining the specific methods that can be called to a smart contract for execution. These specific methods and their connected data types are listed in a generated JSON RPC file.
Source:https://static.packt-cdn.com/products/9781789954111/graphics/assets/fe0f2ffc-2f3c-4615-9cb5-43c8e036239b.png
Unlike an API, we can't just send a request directly in JSON format to a smart contract and expect a response since a contract only communicates in bytecode. To translate this into something the EVM understands, this information is encoded via ABI encoding.  These encodings include function signatures and variable declarations so that the EVM knows exactly which function to execute within the smart contract.
The responses are also in the bytecode so interpretation is required before it is processed by a web application. The advantage of using bytecode in the response is that we can also expect a certain structure to be returned after calling a contract's function.

How to use ABI?
Generation
If you are using tooling like Hardhart/Truffle or an IDE like Remix, the contract ABI is automatically generated for you. You can also manually create the ABI by using the Solidity Compiler NPM package. After installing the package, you can run the 'solcjs contractname.sol --abi' command in a terminal. This will generate an .abi file if performed successfully.
Now that you have a generated ABI, let's look at some of the elements in this file:
Executing
As ABI operates as the interpreter between the EVM bytecode and Javascript of a website,  it is needed when you want to execute any functions of a smart contract. In addition to the ABI, the contract's address on the blockchain is required. Here is a small Javascript code snippet to show how this is done:
If you are interested in finding the ABI of an already deployed contract, you can find this by searching on Etherscan with the contract's address. For example here:
Encoding
Since all communication is done in bytecode, it would be difficult to expect developers to encode these messages themselves. Fortunately, popular compilers like Remix can also handle the encoding for you. These encodings follow a certain pattern, so one can have a better idea of what is going on by reviewing the ABI Specification.
The first four bytes are the function signature which indicates what type of function in the smart contract is being executed. A popular function identifier is a9059cbb which indicates that this is an ERC20 transfer. There is a database directory of function signatures here where you can explore more.
Source: https://miro.medium.com/max/1400/1*YDi7sDUmAc3wjN8TcIBrog.png
From the fifth byte onward are where the arguments are encoded. Responses follow this similar structure but without the function signature included.

Conclusion
ABI can oftentimes be an overlooked aspect of working with smart contracts but it plays an important role in the usability of this technology.  Building on smart contract tutorials is a great way to understand the power of this silent workhorse and a great way to apply your knowledge.
Source of this article - https://www.alchemy.com/overviews/what-is-an-abi-of-a-smart-contract-examples-and-usage


Bitcoin regulation by country

Question: I am looking for a straightforward Bitcoin regulation list accepted in each country. About how it's legal, illegal or denied and if it's legal is there any specific rules in each country?
Answer: There is a page on Wikipedia that tracks Bitcoin legality by country or territory.
Another one can be found on Coin.dance.

Bitcoin regulation by country


Schedule kill of port connections

Question: We use VSS in our company, but have numerous cases were we can't backup the databases as users have locked them.
Is there a way to schedule a kill of all connetions to the source safe service. Or any Rekommandation?
Regards,
Alan
Answer: We had a similar problem with our time and billing system database.  People would forget to exit the program or log off on a fairly consistent basis.  Our solution was to force workstations to reboot nightly prior to the backup being run.
Essentially, we organized our computers in Active Directory by creating folders.  We then created a wrapper file that runs the psshutdown tool from SysInternals (now Microsoft) to remotely shutdown all of the computers in a particular folder on our AD structure.  It works pretty good.
If somebody has a valid need to keep a machine on overnight, such as a long running process, all we have to do is move their computer out of the Workstations folder and then put it back when they are finished.
Answer: net stop server /y
will force shutdown the server process serving up the fileshare where the vss library lives.
i'd caution you on this because if the client is writing at the time you do this, you will get a corruption.
If you can be confident that everyone's out of the office and not using it, you should be safe enough.
net start server will bring the service back online after the backup.
M.
Answer: Hmmm, stopping the server service seems a bit extreme.
You can disconnect network connections in Computer Management by navigating to "Shared Folders" then "Open Files" and right clicking the connection. This is a graphical app and isn't any good for running from a script, but I'm sure I have seem a command line app that does this and can be scripted. However it's name has slipped my mind :-(
Some Googling found http://technet.microsoft.com/en-us/library/cc783450(WS.10).aspx and http://support.microsoft.com/kb/290585, which describe some rather clunky ways to do this. I'm sure there's an app that does it in one go.
I actually wrote a command line app to close connections back in the NT4 days. If you want it (and the source) I'd be happy to oblige, but as I say I'm sure there is an MS applet that does it.
JR
PS Aha! The applet I was thinking of is openfiles.exe.

Schedule kill of port connections


Why is settings.php in the web folder?

Question: In the default installation, settings.php is located at sites/default/. There are no recommendations in the official Drupal website about changing the location of this file. Doesn't it pose a potential problem of security? I have seen Apache webservers eventually failing to interpret PHP files, and serving the content of the PHP file in pure plain/text format, instead of the supposed HTML content. That would completely expose the database connection user and password, which is not even encrypted. Why does it work this way?
Answer: You are absolutely correct. I know for a fact that many developers/sysadmins do not take the risk that the PHP interpreter might fail at some point, and include the db password (and other sensitive data like API keys) from a file outside the webserver's docroot.
I'm surprised that this is not documented as a best practice anywhere - at least I couldn't find it on drupal.org either. I have no information why it works the way it does.
Comment: I remember seeing a discussion between core/well known devs some years back where they argued _against_ moving sensitive data out of the web root. I remember being quite horrified at the time. If memory serves me right, I think the argument was related to to Drupal needing to work out of the box on shared hosting, and these recommendations would make that harder to realise for the masses or something like that. I'll see if I can find that discussion
Comment: Thanks @Clive. I didn't want to add speculations to my answer, but like you say, the requirement to work out-of-the-box on all kinds of environments seems the most likely reason to have settings.php inside the docroot.
Comment: Yes, @marcvangend, this is what I thought myself, but somehow an automatic procedure may be available during installation which checks if there are the appropriate write/owner permissions at the server level, and if this is the case, to provide additional security, in a standarized and controlled (via core methodology) way.
Answer: On some providers this sensitive connection string is stored external to the web root (i.e., getpantheon.com) You can always create some symbolic links instead of storing directly in /sites/default folder.

Why is settings.php in the web folder?


Why does downvoting hurt my reputation (but upvoting does not help it)?

Question: I feel that legitimate downvoting is disincentivised by the rep penalty. What are the reasons this penalty exists?
Comment: [Isn't this a dupe](https://rpg.meta.stackexchange.com/q/3698/22566)?
Comment: The title indicates you may be interested in why up voting doesn't give you a point or two, but the body has no such implication. I think you will get information more in line with what you're looking for if you either remove the parenthetical from the title, or edit the body to ask why you don't get points for up voting.
Comment: @JoelHarmon The parenthetical is there as a justification for the question, pointing out the contrast. The meat of the concern is certainly not there though.
Comment: @Korvin Good spot. I agree it probably is. That question now has the down-votes tag.
Answer: Downvoting is disincentivised (it's not just you), and that's deliberate. The help page on downvotes says this: "Voting down answers is not something we want you to take lightly, so it is not free."
Stack Exchange's engineers want us to think carefully before we downvote something, want us to make sure it's worthwhile. A tiny -1 ping to our reputation is just enough to make that happen. I could go downvote every single post for fickle reasons, but that tiny little penalty gently gamifies me into only downvoting when it's serious and necessary.
Downvotes on questions are free however. That's the case because we badly need people to downvote bad questions so that the site only has good material to respond to, and don't want them thinking twice about whether it's worth it. The downvote help page links to Optimizing For Pearls, Not Sand to explain this philosophy.

Upvotes don't come with penalties nor benefits (such as a corresponding +1 rep for the voter). We want people to vote early and vote often, so there's no cost. There cannot be a +rep benefit for upvoting though. Reputation is strictly only awarded for those activities which concretely benefit the site: posting good questions and answers, making good edits (as a low-rep user), and accepting an answer that's helped you. People want to do things that give them reputation, reputation rewards need to be implemented with the careful question: "what would happen if people did this as much as possible without stopping?" If we were all just contributing awesome questions and answers, good helpful edits, and accepting the answers that solved our problems, we've got a lot of constructive users. But if people were voting constantly on everything, we compromise the upvote as a signal of "this is good" because it could also mean "this is crap but I wanted +rep for voting on it" and our scoring system would collapse.
Comment: This answer would be improved by talking about the question's observation that upvoting is not penalised, and discussing why downvoting is treated differently from upvoting (similarly to how you've already explained why downvoting *answers* is different from downvoting *questions).
Comment: @BESW How does that look?
Comment: While I like how this answer is phrased, I think the question is [a dupe](https://rpg.meta.stackexchange.com/q/3698/22566).


MTS MBlaze 3G USB Dongle in Mint 14 Cinnamon

Question: I recently installed Linux Mint 14 Cinnamon 64-bit along with Windows 7. I have a MTS Mblaze 3G USB dongle. This dongle has 2 modes i.e., 1X mode which gives less speed up—to 30 kbp/s and a broadband mode which gives more speed—up to or greater than 500 kbp/s.
In Win 7, this dongle works fine in broadband mode.
For using the 3g USB dongle I followed steps from this page:
http://telecomtalk.info/step-by-step-guide-configuring-usb-modem-ubuntu/101849/
It's good that Mint has inbuilt support for MTS dongles. But I am facing a problem as I cannot use my dongle in broadband mode in Mint. I have to start Windows, change the dongle mode to 1X mode and then start Mint. Then it connects to internet with 1X mode only giving less speed.
How can I connect the dongle in Broadband mode in Mint?
I also tried using wvdial but it gives an error as /dev/modem not found.
Answer: Solved the problem.
First generate the wvdial.conf file using sudo wvdialconf. Change your user name, password and Phone number in /etc/wvdial.conf file.
Then run wvdial. Dongle will connect in broadband mode.


Is it possible to have a hybrid lighting setup with flashes and studio lights?

Question: From what I've read so far, one the decision you have to make when interested in lighting work is either going with flashes or studio lights.
Can we use both at the same time ?
Answer: Yes, you can use wireless triggers, sync cords, optical triggers, etc. to trigger both portable strobes and studio lights.  If you are using (preflash) TTL instead of all manual, it will be slightly more difficult.  You will have to attach the wireless triggers/sync cords to the controller.  Or find optical triggers that ignore preflash.
There may be a difference in color that you should be aware of (e.g. to correct with gels).
Comment: +1 on the color. It's probably important to note that the correction will have to be on the flash or strobe, not in post-processing. It would be very difficult to do it after the fact.
Answer: It sounds like you're asking strobe/flash vs constant studio lights. It is possible to mix them, but honestly to do so you need pretty powerful studio lights, and pretty weak strobes. Otherwise the amount of light put out by the strobes in the fraction of a second they fire is going to pretty much wash out any light from the studio lights as as to make it pretty much irrelevant as far as the final exposure matters.
Here's a case in point. This is the sooc image:

When I shot that there were two large soft-boxed strobes in front of her (basically I was shooting between them) and a third strobe with a grid overhead and camera right as a hair light.
In the full sized 100% crop of her right eye, you can see the reflection of the soft boxes pretty well, and almost make out the difference in the power levels (one was at 3/4 power, the other about 2/3 if I remember correctly... I had to turn them down so that the weaker strobe over head at full power gave enough light to the hair).
Additionally in the room, there was a fairly bright work light behind and camera left of her, that was our work light so we could see between flashes. You'll note there is no hint of light from that side. In the 1/200th of a second the shutter was open, there wasn't enough light from that source to mater. (f/8, ISO 100 to complete the exposure data.)  I looked through my cull pile from the shoot, but I can't find any shots that showed the effect of that light... I suspect the one that would have would be one where the radio popper failed and the strobes didn't fire... but that probably got deleted. What I recall seeing was that her right shoulder had a serious edge light and it cast a shadow onto her neck from her hair. That light would be about as bright as any constant studio lights I've ever seen, and it just didn't compete with the strobes.
Here's the final shot after some TLC in LR:
Answer: I am a bit confused with the terms "flashes or studio lights"
Studio light is one light that you use... in a studio.
It can be artificial, either continuous light or strobe (flash) or it can be natural light.
In strobes, you can have monolights normally with a modeling light or you can have portable flashes.
But yes, you can use whatever you want, need, can, have. You can inclusive use bioluminescence if you want.
I must say knowing how to combine them, especially ambient light with strobes, is really interesting.

is either going with flashes or studio lights

You need to see what is the main reason for your light overall.
If you are doing still life photography you can use low power continuous light, but if you are taking photos of people, normally you want to use flashes, that have more power output and the ability to freeze movement because normally people do not stay still good enough to use low powered lights. But with a better sensor, this is changing.


Fundraising event - can I sell tickets AND collect donations?

Question: My organization is hosting a fundraising event at which the tickets are not expensive and participants can contribute an additional amount as well. How would you set this up? Currently I have a price list for the tickets, but I'm unsure how to do the write-in additional contribution. Linking to the donate page could be done, but isn't ideal. Thoughts?
Answer: one way you could do this is to create one field in your priceset for the ticket (probably making it required to ensure that they actually purchase tickets), and then another field (not required) that's a text field with a value set to 1 (which will multiply by the amount they enter), e.g., https://www.screencast.com/t/Db1nHAWfA (You can also set the financial type to something besides Event Fee for the additional contribution, if desired.)
Lesley
Comment: Exactly - that's how - the Financial Typing is going to be important if you're going to be issuing Charitable Donation Tax Receipts.


What is the difference between "gaja", "ĝoja" and "feliĉa"?

Question: Gaja, ĝoja and feliĉa are all happy in English. But I have gotten the impression that they are not synonyms. What is the difference between the three adjectives? When should I use each one?
Comment: Good question. I always just use feliĉa because I like keeping things simple. I have always assumed, perhaps falsely, that they are similar to the English words that we don't hear anymore except at Christmas. Gaja (gay/merrry) - ĝoja (joyful) - feliĉa (happy).
Answer: Feliĉa is happy as in content. This is not the best translation but reflects the long-term nature of the status. You are feliĉa if you have a good life, a happy family, no troubles. You can largely influence this feeling by your life decisions, or the general feeling of luck. Actual luck (getting a good roll in dice) can also be described by feliĉo, but that's probably just an influence of the earlier languages.
Ĝoja describes the transient feeling of happiness of something that made you feel good. I think a close word in English is to rejoice (the base form ĝoj/i is also a verb). You can ĝoji for someone close's success, for example. It does not automatically make you feliĉa. But you probably are a feliĉa person (in general) if little things like seeing flowers (individual events) make you ĝoja.
Gaja is what English traditionally described as gay: cheerful, jolly, merry.
One can be gaja (cheerful) when dancing and laughing around at someone's wedding, while being ĝoja (rejoicing) for one's friends' big day, and feliĉa (happy) realizing how good it is to have friends and opportunities for a good time.
Another example is that one would probably not rejoice (ĝoji) in being poor, but could easily feel more feliĉa than someone rich but living under stress and fear of a sudden loss. On the other hand, one can be ĝoja for winning a lottery despite otherwise being malfeliĉa because other things haven't been going so well lately, or because of one's depressive mood.
Answer: Shooting from the hip here (i.e. without checking references)

Gaja has to do with frivolity, enthusiastic celebration, and levity. Ni gaje kantis.
ĝoja is related to the joyful emotion that you feel from within. Mi ĝojas pro via sukceso.
feliĉa can also describe an emotion, but often has to do with luck or good fortune. Feliĉe tio ne okazis.
Answer: I think it'll be hard to explain the difference using the English language, but let me try!

gaja refers to one's state, mood. It can be seen in the external signs: gestures, smile, laughter.
ĝoja refers to one's character or feeling of pleasure in one's heart, caused by perceived goodness (real or imaginary) around oneself.
feliĉa refers to one's fate, fortune, luck or good chance, feel of satisfaction with one's life and thus is much more long-term thing.

So scientists may study how feliĉaj are people, what qualities of life make them feel long-term satisfaction. Optimists are ĝojaj people, because their temperament makes them always look on the bright side of life. But from time to time everyone can be gaja, because of a good joke, or malgaja, because of sad news. It's a short-term state, independent from one's life satisfaction or natural tendencies for optimism or pessimism.


Design Using Gimp

Question: A gimp newbie. Does anyone know any tutorial that I can use to create an image like this?
Comment: Hello @Ouya, welcome to GDSE. We're here to help designers with issues they might run across. Complete tutorials are a bit out of scope though, there are other places on the web better suited for that. Please refer to [how to ask](http://graphicdesign.stackexchange.com/help/how-to-ask) for more information. Some terms you might want to google to find applicable tutorials: _clipping mask_, _masking a layer_.
Comment: If you need some Gimp hand-holding, check out http://gimpforums.com/ (mods, please remove if you think this is out of scope, even though PieBie's answer makes me think this can be useful).
Comment: The same question for Photoshop: http://graphicdesign.stackexchange.com/q/71543/52050
Answer: In Gimp:

Open the texture picture
Use File>Open as layers to open a the lion picture as a new layer
Scale/move the lion layer
Use one of the selection tools to make a selection following the shape of the lion (this is indeed the hard part... the adequate tools depends a lot on the lion's picture, this can take from a couple of seconds to a god half hour)
Hide the lion layer, select the texture layer
Select>Invert to select the layer outside of the lion
Layer>Transparency>Add alpha channel if you want something different from the default background
Edit>Clear to delete the selected area.
Answer: I don't know the exact way to do this in gimp but in Photoshop this is not that hard.
What you need here are two pictures (obviously).
For example

a picture of an apple
a picture of the sea

If you want the apple to have the "texture" of the sea picture, all you have to do is selecting the entire outline of the apple and create a clipping mask using that selection you just made and the picture of the sea.
Normally the picture of the new "texture" has to be below the mask.
So in this case your layer order would have to be:

Layer 1 Apple (I am a clipping mask now mom!)
Layer 0 Sea (I am providing the texture now :D)

Tip: If you plan to use more than those 2 layers in your document, I recommend to merge those layers as soon as youre done. Clipping masks can get confusing pretty quick if you don't know exactly what you're doing and don't take care of them soon enough by merging them into something "normal".

Design Using Gimp


Meaning of the phrase "Tzur Chevli B'eit Tzarah" near the end of Adon Olam

Question: Near the end of Adon Olam, there is the phrase "Tzur Chevli B'eit Tzarah". What exactly is the meaning of this phrase, and specifically the term "Tzur Chevli"? I have seen it translated rather literally as "Rock of my pain in my time of distress" (Artscroll), which does not seem particularly intelligible, at least to me. I have also seen it more or less glossed over like "The Rock on whom I rely" (Koren), which, while it makes sense in context, kind of ignores the meaning of the words. (I'm only picking on Artscroll and Koren since I happen to have both siddurim with translation at home). It is entirely possible that I am over-thinking this, and it means something like "He is a Rock for me when I am in pain, or am in a time of distress"; however, it seems like the term "Tzur Chevli" means something more specific. Any thoughts?
Comment: Welcome to Mi Yodeya, and thanks very much for bringing this interesting question here! Please [edit your profile](http://judaism.stackexchange.com/users/edit/7442) and give yourself a name, unless 3656711 is somehow special to you. I hope you'll look around find other content here that's meaningful to you, perhaps starting with our 121 other [tag:song-poetry] questions.
Comment: Sort of similar http://judaism.stackexchange.com/q/29122/759
Answer: A possible interpretation can be gleaned from the posuk in Yechezkel 27:8 where the term rope is used metaphorically to signify the ones steering the ship. And in Shmuel II 8:2 ropes are used metaphorically to signify control over life and death.
Thus in keeping with the theme of the piyut that Hashem is "Master of the world", we praise Hashem by confidently stating that he is "the Rock of my rope(s) in the time of distress" - meaning that Hashem is complete control of my distress. That any suffering which I experience is not due to happenstance (in which case the suffering could be uncontrollably nasty), but comes from Hashem who carefully measures the amount of suffering that I need and that He knows I can bear, and which is being brought upon me intentionally as an atonement, or in order to arouse me to repent, or for some other reason.
Answer: The Kehot Annotated Siddur translates it as "the strength of my lot in times of distress".
The "my lot" would be like Devarim 32:9:

יַעֲקֹב, חֶבֶל נַחֲלָתוֹ
Jacob the lot of His inheritance

The Siddur Shay Lamorah quotes Iyun Tefilah that it means that He is my Rock and Refuge (מעוז) to save me from the pains which grab me at a time of trouble.

וצור חבלי - והוא לי צור ומעוז להושיעני מן החבלים אשר יאחזוני בעת צרה
Answer: I have looked into this a little in the past, so I can't recall particular sources, but the gist of it is as follows:
Some wish to translate it as in "חבל נחלתו" and many other instances in which it is used to mean "my lot" or "my portion in life". This would parallel the other phrase "מנת כוסי" in the next line. "צור חבלי" would then mean "the Rock who is my lot in life", i.e. who is what my life is about. However, this would not satisfy any grammarians, who know that if this was the intention, the chet would have a patach under it: "חַבלי". But none of the siddurim have such a vocalization. I have seen one or two old siddurim which have a patach, probably just to be able to translate this way but without any manuscript evidence.
As we have it with a segol under the chet, the word usually means pain as in "חבלי מות" or "חבלי שאול" or "חבלי לידה", which from context probably means a time of unbearable pain. In this case, "צור חבלי" would mean "Rock of my pain", i.e. my Rock who helps me when I'm in pain, and the following "בעת צרה" is a parallelism and emphasizing of "חבלי" (with the additional benefit of playing on the words צור/צרה).
An additional possible source for the latter interpretation, I think, is Psalm 18, in which the first few verses express this sentiment of God being always there for you during hard times. Verse 3 refers to God as "צורי" as does the author of Adon Olam in this line, and verses 5 and 6 use the phrases "חבלי מות" and "חבלי שאול" to express painful times. It is possible the author here is alluding to this psalm or using it as a basis for this line of his poem.
Comment: Would the author of the piyyut have written it out with vocalization, or is any vocalization subsequent interpretation? The parallel to Psalm 18 is certainly interesting, but the word isn't necessarily understood as pain there either (e.g. Rashi brings it is as one of two options). But +1 either way.
Comment: @Yishai, Thanks. We do not know who the author is, and we certainly do not have any original manuscripts that we know were written by the author's hand. We would only be able to judge from any existing manuscripts that have vocalization, and those that do have a segol. I'm sure there are plenty of genizah manuscripts that include Adon Olam, and if they find any with a patach, surely we'd find out about it eventually.
Answer: צור חבלי בעת צרה is an idiomatic expression. "צור חבלי" means literally "my rope's rock". It is referring to an anchor. So the plain translation (meaning according to peshat) is "My anchor in times of trouble."
There are many ways to give it allegorical meaning as well as according to the Kabbalistic interpretations. But all these other meanings must relate to the plain meaning (the peshat).
Comment: Is there any other place that a צור חבל or חבל צור or something like that is an idiom for the idea of an anchor in English which is itself an idiom for a source of security and stability. צור alone, or מעוז צור I'm aware of, but not something that adds חבל.
Comment: Not that this is a proof but see "History of the Anchor".
http://en.wikipedia.org/wiki/History_of_the_anchor

Adon Olam was according to some authored by Rabbi Yochanan ben Zakkai. A great deal of his life was spent around the Kinneret. Ancient anchors as described would have been very much a part of his daily experience.
Answer: I noticed that the root form of חֶבלִי is חבל meaning "rope". However, I also did a Google translate on the full word חֶבלִי and it displayed the synonym נָחוּת which has one translation as "disadvantaged". This makes sense, in this context, as the word "chaval" is often said to someone when a tragedy or danger is mentioned. See also this site which gives a further translation and another angle on the word origin of חבל. It slightly concurs with the other one.
So, a somewhat literal translation to the phrase would be "He is the rock of my disadvantage in (my) time of distress."
A metaphoric translation (mine) would be to imagine a rope that is tightened. In a sense, the paytan (poet) is saying, He is the source of my salvation when the "rope" of distress is tightened around me.

Supplement: I'm humbled by the answer that follows mine. This explanation of the "rope" is excellent.
Comment: עֵקֶב עֲנָוָה יִרְאַת יְהוָה עֹשֶׁר וְכָבוֹד וְחַיִּים - Mishlei 22:4
Comment: What just occurred to me is that chevel can mean simply "pain", but it can also refer to a specific type of pain: the pain of labor before giving birth (See Isaiah 66:7, among other places). Also, in Exodus 1:16 a birth-stool is referred to be the word "Ovnaim", from the word "Even" or stone, implying that an Egyptian birth stool was similar to a pair of stones (I just took a lok at http://jwa.org/encyclopedia/article/puah-bible, which basically says this). I am wondering if it is supposed to invoke imply the idea of G-d leading us from travails to joy... continued in next post...
Comment: Similar to how a woman giving birth experiences severe pain (severe being a serious understatement) before, with the help of a midwife/doctor/doula, giving birth, so too, when we feel we are in an "Eit Tzarah" a time of trouble, G-d is almost like a midwife, as it were, "redeeming" us from our travails, and leading us to joy/peace/serenity/happiness. Maybe a bit of a stretch, but it seems to have at least some textual support, and the idea fits the theme of the piyut.
Comment: Actually, the focus between חבל and נחות is not about pain. The process of active labor is called חובלי לידה. The word נחות means "descent", as in נחות דרגה (descent in level) or נחת רוח, which literally means "descent from ascent".

In the process of birth, one of the main stages is the "descent". See: http://library.med.utah.edu/kw/human_reprod/lectures/physiology_labor/

In context with the coming of Moshiach, חבלי משיח is about the descent of the soul of Moshiach, like the descent of the foetus through the birth canal, into this world. The focus is on descending, not pain.


American citizen expat traveling to USA, how can I get liability auto insurance?

Question: I'm an American citizen, but I live in Germany and do not own a car (and thus do not own a car insurance policy). I'm going back to the US over Christmas and want to rent a car, but I don't want to pay the daily rate on liability insurance offered by the rental agencies. Do I have any options for a short-term (1 or 2 months) policy from a big broker like Geico or Progressive?
Comment: I think some credit cards offer insurance for rentals if you rent using the card.
Comment: When I was temporarily expatriate, my overseas insurance did not cover driving in the USA or anywhere other than its country of issue. My credit card did. My former USA insurance agency said that such temporary policies exist, but are very expensive. I suggest calling Geico or Progressive, etc.
Comment: You might look at rental car packages offered by rental car brokers (for example SunnyCars in Germany). Their package does include all insurances, and overall, they may have better deals than you can get directly. You would, however, have to verify if you are eligible for these packages (I believe to remember that they are not available for US residents/citizens (my memory is weak here; it could be residents)).
Comment: Hi, I have exactly the same question! Did you eventually get an answer? Will some company sell you liability insurance for use with rental cars?
Comment: Yes, I ended up just having my mom add me to her policy. It was about $100 for the month that I was in town.
Answer: There is the concept in the US of "Non-Owner" car insurance for people just like you. You can read about the concept here.
Progressive offers coverage specifically for car rentals. Presumably most large insurance companies do, too, so you can call around and pick a price point you like.
Comment: I've just checked, neither Progressive nor GEICO offer this kind of coverage anymore (at least in California).
Answer: I would talk to your credit card company.  That is probably your best bet.  Alternatively, you could have a friend rent and drive the rental car while you use their personal vehicle as many times standard auto insurance would cover you as a guest driver on the personal car and your friend in the rental car.  But, that's a lot to ask of a friend.


What are common criticisms against using the KJV?

Question: I know that many people and churches prefer using translations other than the KJV. Why? What are the common criticisms against it?
Answer: The usual criticism is readability.  The KJV was originally translated in the 1600's, and even though it's been updated several times since then, there are still words that have different meanings now than they did in the English of the time.  The literary style is clearly less modern than more recent translations.
Another criticism is based on the translation sources.  The New Testament portion of the KJV is based on the Textus Receptus (Received Text), which has been subject to some criticism.  This has resulted in some minor textual differences that can be traced back to the different source manuscripts.
I hesitate to answer more completely because the choice of a Bible version is personal, and I want to avoid stating that any version/translation is superior to others.  There are those that feel very strongly about the superiority of their own version (KJV-only and those strongly opposed.)  The textual differences mentioned above tend to fuel such arguments, which in my opinion, tend to be counter-productive.
Another criticism is the distinction between a translation of the original texts, and a paraphrase.  The various  Bible translations fall somewhere on a scale between word by word equivolence and thought for thought equivalence or paraphrase.  The KJV is closer to the word-for-word end than many modern counterparts.
The KJV-only groups tend to prefer a direct translation of the original because it is less subject to be influenced by the views of the translator. They argue that an interpreted version is suspect, because the result is influenced by the translator's understanding of the meaning of the text.  On the other side, the argument goes that the "paraphrase" versions are written so that the meaning is clearly understood, and it's therefore "easier to understand" than the "archaic" KJV.
Comment: When it comes to the KJV-nly debate, I tend to agree with Woodrow Kroll from Back to the Bible: http://www.backtothebible.org/index.php/Q-Which-version-of-the-Bible-do-you-use/recommend.html  I love my King James, but still say that the "best" Bible is one you can read and unbderstand.
Comment: It's not just that the Textus Receptus has been subject to criticism, it's that Erasmus back-translated the Latin to Greek and introduced even more variants. So translation went: Greek -> Latin -> Greek -> English.
Answer: The biggest problem with the KJV is that no one is fluent in its language any more. It simply is not written in an English anyone speaks today.
When you read the KJV the problem isn't words you don't know - you can go look them up in a dictionary like you do any other words you haven't read before.
The problem isn't complicated sentences or strange word orders - you can spend the extra mental energy to parse it even if you're not reading smoothly.
The problem is that words change what they mean over time. You can learn what changes have occurred, and sometimes you'll realise that the words don't mean what they think you do because they don't make any sense in context. But often both meanings fit the context and unless someone has told you that a word used to mean something else you'll just automatically read it with the modern meaning. So the biggest problem of the KJV is the one you don't realise you have!
An example of this is the word 'conversation', which is found in Philippians 1:27 in the KJV. The modern meaning of 'conversation' fits the context perfectly, but it's not the right meaning. Every modern translation, including the NKJV, translates it as 'behaviour' or 'conduct' or something like that. Unless you already knew that 'conversation' used to mean something else you would never think that it did from reading it. Later in Philippians 3:20 the word 'conversation' is used to mean 'citizenship'. I don't know if it used to have two meanings or was just translated poorly, but again it's the same problem. That verse doesn't make quite as much sense, so you might guess that something weird was going on, but you might not.
For five more examples, try this quiz: Do you speak KJV?
If you're willing to check every word you read in the KJV against an Early Modern English dictionary, then go ahead and read it. But if you're aren't, I guarantee that there will be times when you understand it incorrectly without even realising. Please, read a Bible translation in a language you actually know!
Comment: Woohoo! I knew all 5 examples! (Latin vocabulary wins again...)
Answer: What are common criticisms against using the KJV?
Some feel that the Textus Receptus (original Greek and Hebrew) from which the KJV was translated is an inferior collection superseded by the Alexandrian text which is a little older. Concerns regarding the Alexandrian text are that it omits the end of Mark and some other differences. Some consider the text superior as it has been dated earlier and is regarded as less likely to have been altered as Alexandria had a problem with allegorical-ism which would be unlikely to motivate intentional translation alterations. I do not find these arguments sufficiently compelling to abandon the KJV.
One group of criticisms can be made against the KJV as can be made against any translation, particularly "word for word" translations. There is information in a word in one language that cannot be brought over into a single word in another language. For example English is often bereft of verb tense information that is in words of other languages. For example, the English translation may say to do something, the Greek may say to do it as well as indicating that it should be done only once or continuously. The missing information can have a significant impact on correctly understanding what was written.
Some cling to the KJV as a defensive reaction to the publication of various "translations" that seem threatening to Biblical tradition. Readers Digest published a "condensed" Bible in what I assume was a sincere desire to make the Bible more accessible. This is slightly different than using simple language to help those less able to understand as it helps those more easily bored. Then there are translations like "gender neutral" translations that are more alterations to advance a particular ideology. Those who use the KJV to hold at bay the invasive and corrupting forces at loose in the world, may find that they hinder themselves from the use of translations that could open greater understanding to them.
The most significant charge that can be made against the KJV is that its language (Shakespearean) is difficult for many today to easily comprehend. In all fairness, even some of the ideas are as difficult to digest as the language. A reason for these difficulties is the conversion of the populace into entertainment consumers. There is no reason for people to want to put forth the effort to read arcane language when they have little desire to grapple with difficult ideas.
One has to consider the dynamic power of God through his word. We can all too often see the Bible as a textbook or instruction manual and forget that it is God who works through it.

Deuteronomy  8:3  And he humbled thee, and suffered thee to hunger,
  and fed thee with manna, which thou knewest not, neither did thy
  fathers know; that he might make thee know that man doth not live by
  bread only, but by every word that proceedeth out of the mouth of the
  LORD doth man live.
1 Corinthians 2:14  But the natural man receiveth not the things of
  the Spirit of God: for they are foolishness unto him: neither can he
  know them, because they are spiritually discerned.

Even though there is a constant and swelling assault on the Bible, we should remember that it is God's word and he will protect it.

1 Peter 1:23-25  Being born again, not of corruptible seed, but of
  incorruptible, by the word of God, which liveth and abideth for ever.
  For all flesh is as grass, and all the glory of man as the flower of
  grass. The grass withereth, and the flower thereof falleth away:   But
  the word of the Lord endureth for ever. And this is the word which by
  the gospel is preached unto you.
Answer: To answer your question directly, the most "common" criticisms are that (a) the form of English used is arcane and (b) the manuscripts upon which the text are based - especially the New Testament - are somehow inferior.
I am not sure either of these criticisms are completely warranted.
One advantage of Elizabethan English is that it retained a distinction between the second person singular (thou) and plural (you) and was therefore better able to mirror the underlying Greek text.  In modern versions such as the NIV or NASB, this distinction is loss, so one does not know, for example, when Jesus is addressing an individual or a group.
Regarding the second criticism, antiquity of the manuscript is not really any indication of authenticity.  It is a hypothesis that cannot be proved, since we no longer have (or maybe never did have) the "autographs".  The oldest New Testament manuscript we have may be 100 years older than the next oldest, but the fact remains that whatever we do have was written centuries after Christ in any case.
Another criticism that is sometimes laid against the King James Version is that it contains errors.  These include Luke 13:32, which states Go tell that fox ..., even though the Greek says "this fox" and not "that fox";  John 5:28, which is punctuated to reproduce a heretical reading posed by Paul of Samasota in the 3rd century and refuted by John Chrysostom in the 4th; John 3:3, wherein the Greek indicates that Jesus really says that Nicodemus must be born from above, but the translation says that he must be born again.  These, however, are errors that also have propagated into more modern translations as well.


User profile public page

Question: I'd like to manage my users (both active site users, and other employees at my client's company) via the Craft user management. I've added more profile fields, etc. But i'm wondering, is there a built in public profile page/route for users?  I'm listing various users on a page, and i'd like their profile image to link to a profile page for each of them, with more info, contact info etc. What's the best way to do this?
Comment: To my knowledge, there is no built in user routing. What exactly are you trying to achieve? Are you wanting to display a profile of a staff member or user at the url (i.e. `/profile/{{ username }}` )?
Comment: Yes, I'm trying to display profile pages for users in the system.
Answer: You will need to add a custom route for the path for which you want to show the profile from a list of all users.
Per my example of /profile/{{ username }}:
In your profile/index template, you would run a loop on the user set of your choice:
{% set users = craft.users %}
{% for user in users %}
    {{ user }}
{% endfor %}

Craft Admin › Settings › Routes
New Route
If the URI looks like this: profile/* (Use the * token provided)
Load this template: profile/_profile

Then, in your profile/_profile template,
{% set user = craft.users.username( craft.request.segment(2) ).first() %}

Once user is defined, you can use the UserModel to return any data from that user (i.e. {{ user.email }} ).
Answer: If you simply need a public profile page, you can build that easy enough.  Simply pass in some user identifier through the URI /profile/username or /profile/userId will do.
Then from your template:
{% set userId = craft.request.getSegment(2) %}
{% set user = craft.users.id(userId).first() %}

Now user is a UserModel and you can access any of those properties of it as well as any custom fields you've assigned to users.
Additionally, you can create templates on the front-end for user management.
This includes public registration, editing user profiles, password reseting and logging in.
Comment: @user412 Brad did show you how to do the basis of that very easily. You just need to write your template to access the user profile fields you want from 'user'. The rest is optional, if quite helpful to see how to do it ...from one of the founders of Craft.
Comment: i don't need front-end user management, just want to be able to have a public profile page for each user in the system.

User profile public page


Why does quantum error correction work?

Question: I read about some QEC codes such as Shor code. It encodes a logical qubit to 9 physical qubits, to correct the bit-flip and phase-flip error. To do this, it needs multiple $\mathrm{CNOT}$ and $\mathrm{H}$ gates. As we know, the increase of the number of operations brings errors. How can this procedure then decrease the overall error rate?
Answer: Quantum error correction concerns errors that happen on qubits; it does not provide any protection against errors in operations on those qubits.
Note however, that an error on an operation can be seen as the perfect operation plus some error 'on the qubit'. It is, however, the case that, without any precaution, the added operations introduced by error correction invoke many more extra errors than that the code might be able to correct. This is indeed a very though issue.
The answer is, in short, what is collectively known as fault-tolerance. This is essentially taking much, much effort to implement all operations included in error correction in such a way that the extra errors that might arise during this operation do not pile up, thereby exceeding the error correction capabilities of the code.
It has been proven that, taking enough precaution, one can correct errors quicker than they arise: The threshold theorem. Note that fault-tolerance requires very much resources (qubits and operations). Fault-tolerance is quite tough, but for an idea behind it see the second half of the introduction by Gottesman.
Comment: No, QEC is very much needed for a 'full-scale universal' quantum computer. However, only using QECC's will never be enough, as I explained in my answer it is only one side of the coin; the other side being fault-tolerance. Hardware needs to be good enough so that errors can be corrected faster than that they arise. The extra errors caused by the error correction itself can just be regarded as any other error (if the implementation is fault-tolerant). Such a full scale universal quantum computer is also often referred to as a fault-tolerant quantum computer.
Comment: Thanks for your answer. For example, if we create a circuit using qiskit. Since the extra errors are caused by the error correction, how can we use the error correction code to decrease the error rate on the real device? Does it mean that the quantum error correction is just a thought experiment and it cannot apply to any real device?
Answer: It was my understanding that error-correction does not really apply to quantum computing. The elements in the set are not numbers, they are probabilities. Probability elements are never in one state or another. They are always in all states. That is the beauty of quantum computing.
Comment: This is incorrect, there is a whole subfield in quantum computing concerning (quantum) error correction and fault-tolerance. A universal quantum computer will  very, very likely need some sort of error correction. Please elaborate more on what you mean by 'the elements in the set are not numbers, they are probabilities.' Thanks in advance.
Comment: Thanks for your answer. But I am still very confused. If error-correction does not apply to quantum computing, what is it used for?
Comment: EC applies to computation of sets where the elements are deterministic.
Comment: Sure. A qbit exist in all states at different probabilities depending on how one manipulates it. For some algorithms, this is a plus. It is possible to look at a problem from many different angles at the same time.
Comment: @DaroGross: But eventually you have to measure qubits and you get some answer. This answer is one partiuclar state the qubits collapsed to after measurement. It is true that qubits are described by probability distribution. However, because of noise the distribution is distorted and this cause errors. You have to have some mechanisms how to correct them.
Comment: Don't look for simple deterministic answers. Try asking questions where the answers themselves are probabilities. Not all problems are appropriate for this kind of computation, but that is what quantum computers do best.

Why does quantum error correction work?


Why the specific commandments in the Aseret haDibrot

Question: What is HKBH trying to teach us by his choice of commandments that make up the Aseret haDibrot
Answer: Rashi (Shemos 24:12) writes that the ten commandments are 10 categories which the 613 fall under.The Bamidbar Rabbah writes that there is 620 letters in the ten commandments 613 for the mitzvos and 7 for the rabbanic mitzvos.
It should be noted that singling out asres hadibros is not so simple because we don't want to show that it is more important than any other mitzvah.See gemara Berachos 12 where they tried to insert aseres hadibros into davening.Also standing for aseres hadibros when read is also not so simple see tshuvos HaRambam.
Comment: Shemos 24:12: את לחת האבן והתורה והמצוה אשר כתבתי להורתם: כל שש מאות ושלש עשרה מצות בכלל עשרת הדברות הן, ורבינו סעדיה פירש באזהרות שיסד לכל דבור ודבור מצות התלויות בו
Comment: I moved this answer from http://judaism.stackexchange.com/q/29906, where you posted it. You may (but may not) wish to edit it to better match the wording of this question.
Comment: What are the seven mitzvot derabbanan?
Answer: There are many reasons.  Gershon pointed out the balance between those for God and those for other people.  The Ralbag and R' Saadiah Gaon hold that all other mitzvot can be derived from these ten -- they are, in a sense, "summary" mitzvot.  The source for this seems to be Bamidbar Rabbah 13:15.  (Thanks to RCW, Alex, and jake for these sources.)  Another (this may be more modern) is that they are the foundation of a functional society.
One might also ask why we think there are exactly ten here (besides "tradition", I mean), and why ten is a special number.
Comment: @RCW: as does R' Saadiah Gaon.
Comment: @RCW, @Alex, The source of this idea is actually in Bamidbar Rabbah. I have the specific source written down somewhere, and will iy"h post it when I find it.
Comment: The Ralbag holds all the mitzvot can be derived from the Dibrot.
Comment: @RCW, @Alex, Found it: [Bamidbar Rabbah 13:15](http://hebrewbooks.org/pdfpager.aspx?req=37456&st=&pgnum=109).
Comment: They are the first and root commands (Mishna Tamid 5:1).
Answer: The first 5 are commandments that are between man and G-D, the next 5 are commandments that are between man and his fellow man. This shows that they are of equal importance.
Answer: I think its clear why the first 8 are part of the Aseres haDibros:

God's existence - Most fundamental principle of Judaism
No Idolatry - Worst sin in Judaism
No false/vain oaths - Once recognize God, must respect His Name
Sabbath - Testimony to God's creation of Universe.
Honoring Parents - God and parents are partners in a person's creation.
7, 8.  Don't Murder, Don't do Adultery, Don't Steal/Kidnap. These are the 3 [worst] categories of sins to other man.

The other 2 are perhaps less expected:
9- Don't do False testimony - This is  a way of causing terrible harm without physically doing anything, and involves perversion of justice too.
10- Don't Covet - This affects the person who covets, and may lead to other sins also.
Answer: The number ten represents :

the number of fingers on both hands, which, apart from constituting a good mnemonic, also has a deep mystical connotation, in light of man being made in God's image, according to the "Bereshit" parashah of the first book of the Torah;
the numerical value of yod, the first letter of the Holy Name;

as well as :

the number of plagues against the Egyptians, which oppressed Israel;
the number of the main or principal commandments given through Moses to Israel on Mount Sinai, which, when explicitly unpacked, yield the 613 mitzvot.

Notice the connection between the first two meanings :

God, whose Name's initial letter has the value ten, creates man in His image, whose members (hands and feet) have ten fingers each.

Notice also the connection between the last two meanings :

by ten deadly plagues He chastises Egypt, and by ten life-giving commandments He blesses Israel.

Notice also how the four fingers and one thumb on each hand mirror the inner structure of the ten commandments :

the two hands represent the two tablets;
on each hand, the thumb is set apart from the rest of the four fingers, just as the last commandment in each of the two groups of five commandments is set apart from the first four within the same group.

To better unpack what I meant by the latter remark :

within the first five commandments, the first four are concerned with God, the Heavenly Father of all Creation, whereas the fifth is concerned with our human or earthly fathers and mothers.
within the last five commandments, the first four are concerned with outwardly or physical sins, listed in decreasing order of magnitude, whereas the last one is concerned with inner or spiritual sinfulness.

Then the following chapters, containing the rest of the mitzvot, are nothing else but an unpacking of each  commandment from this initial tenfold set of divine laws, relating to them as the seed or root would relate to the rest of the plant. Thus, the sixth reading of the Kedoshim parashah, for instance, is a footnote or commentary to the seventh divine commandment; etc.


Assign KVM VM to a user (KVM user authorization)

Question: I would like to give my friend a VM on my dedicated server, and I want him to be able to  restart the VM or change the iso - so basically I would like the same features as a VM hosting provider, e.g. Linode. I guess the easiest solution would be to give him a shell account, but how to restrict the shell? Is it possible to restrict libvirt for my use case?
Answer: I don't know of any way to do this directly, though you can install a control panel like Proxmox and give him access through that.
Answer: libvirt doesn't have any user access control over individual VMs, so your best option is probably to write a series of wrapper scripts around virsh (one to reboot the VM, one to stop it, one to start it, one to change the ISO image, and whatever else you need), and then give your friend sudo access to those scripts from his login account.
The wrapper scripts should be written with hard-coded values (e.g. for the VM name) and careful checking of any user-supplied data.  e.g. make sure that if he provides an ISO image filename that it is actually an ISO image and that he has read access to it.
e.g. if the VM is called "FriendVM" then a reboot script might look like this:
#! /bin/sh
# Script Name: Reboot-FriendVM.sh

virsh reboot FriendVM
Giving him sudo access to that script will allow him to reboot ONLY that particular VM.  He would run it like so: sudo Reboot-FriendVM.sh
Similar wrapper scripts around 'virsh start', 'virsh destroy' are easy to extrapolate from that.  A script to change the ISO image would be a little more complicated and is left as an exercise for the reader :)
Another variation of this idea if you don't want to write lots of little scripts is to write a single script with a restricted subset of virsh capabilities that work only on his VM and give him sudo access to that.  e.g. call it rvirsh.
That's the simple, minimalist way, just enough to get the job done with no frills.
If you have more time to spend, you may also want to look into virtualisation management software like openstack, google's ganeti, opennebula, and others.  They do a LOT more than just adding user access control though, and learning them will require a significant amount of time and effort.
Comment: BTW, just in case it's not obvious - you almost certainly don't want to give your friend complete sudo access to everything, just to a defined set of scripts.  You'll need to look up the documentation for sudo and especially /etc/sudoers.  and search here on serverfault for 'sudoers'.
Answer: Most unfortunately there is no way which is stable, "clean" and update-secure to do that - besides using a web-interface or writing your own one.
Comment: Do you mean writing my own shell by "writing your own one"?
Answer: If you're already using libvirt, and following the Web Panel suggestion made by others, you may find Karesansui interesting: http://karesansui-project.info
Proxmox is AFAIK the easiest_and_featureful virtualization environment management solution.
Ganeti+Ganeti Web Manager (currently studying it) seem also very nice and powerfull.