Could the Hoatzins wings evolve into arms

Question: The Hoatzin is a jungle bird whose only remarkable trait, other than looking fabulous, is that their wings have fingers.

Is it possible that these wing fingers could evolve into arms? What about legs? What pressures would lead to such an evolution?
Comment: Since wings evolved from arms, there is no reason they could not evolve back....
Comment: Yes, the pressure of needing arms..
Comment: I'm thinking maybe due to irreversible climate changes all the tropical fruits and nuts developed hard shell to retain more water etc, these Hoatzin may grab any sharp objects to pry open the thick shell similar to monkey. They can also play barrel of Hoatzins with their spouse and chicks during typhoon season...
Answer: I don't know exactly why you want the hoatzin to evolve hands, and the birds already have legs, but the best answer is to make the birds need to climb. At present, only the chicks need to climb, so only the chicks have claws, but the adults are pretty bad fliers, so it wouldn't take too much to push them to stop flying all together. This simplest way for this to happen would be for the climate to change a little.
Let's say we have a rain-forest just perfect for the modern hoatzin. It's got lots of trees with lots of branches perfect for hoatzin nests, and lots of leaves for the birds to eat. Now, hoatzins really only glide from branch to branch, they don't really flap much because their muscular structure really isn't set up for flapping. If the hoatzin didn't have a lot of branches fairly close together, it would have a right difficult time getting about. Of course, in a rain-forest there are lots of trees with lots of branches all very close together because there is plenty of sunlight and water for all of them. What would change this could be a climactic shift, I would propose to a wetter but cooler climate.
All this would take is some cloud cover.
With less sunlight, the trees devote all their energies to being taller and they put all their branches up top, where they can gather sun. The lower levels of the jungle are plunged into almost total darkness, very bad for plants, so the trouble of branches all over the place is cleared up. When the birds fall out of the nests, or out of the trees, or end up in the water for whatever reason, they have to climb to get back up into the trees. There is no longer the option to fly up, especially not out of the water.
Then, with clouds comes rain. Lots of rain. The hoatzin already lives where there is a lot of standing water, so it wouldn't take too much to flood the rain-forest floor. This would take care of all that pesky underbrush that the birds might use to hop-fly back up into the trees. Think swamp: tall trees sitting in water, not too much cluttering up the way-up from the ground-level.
The hoatzin sits on its eggs more to keep them cool than to keep them warm, so the birds can't be away from the nest for too long. Climbing up and down the trees isn't the fastest thing to do, so a cooler climate would help select for climbers, or at least, not select against climbers.
The original needs for climbing (get back to the nest, climb out of the water) are still present and are exaggerated. What's more, this shift in climate can occur with some rapidity. It wouldn't take eons and eons for a jungle to turn into something of a swamp, which means that the birds will be forced to select for a right-now trait (like claws that remain into adult-hood) instead of a slower trait (like a progressively better flight muscular structure), but it will take long enough that the birds would have time to evolve, not just be wiped out by the sudden change in conditions.
As the rain-forest becomes more and more swamp-like and the foliage changes, the hoatzin will have even less need or opportunity to fly. In the beginning, the birds will still fly between the tops of the trees, but with the expanding breadth of the tree-tops, they won't have to. As the trees strive to collect as much light as possible, their canopies will become less vertical and more horizontal, so the hoatzin will be able to hop more than fly, and its progressively longer-lasting claws will help it to do so. When these original trees die, the dark ground level will not permit as many saplings to take hold, so in perhaps a hundred years or more, when the first trees have died and the second generation has begun to rise, the forest will be less dense, meaning the trees don't have to compete as much for the light and their canopies will thin out again. At this point, the hoatzin has experienced some 30-40 generations since the environment began to favor adult claws. That's not a lot, but it's enough to give the hoatzin 2.0 a good basis of flightlessness because along side the selection for claws, the hoatzin is experiencing a lack of selection for flight structures. The reason the modern hoatzin does not fly well is because the structures needed for it to eat leaves conflict with the structures it would need to fly, so when the balance is tipped, relieving the need for flight while holding the need for digestion steady, we will see the worsening of flight structures. With the trees becoming farther apart, the hoatzin will have to get from one to the other, but it's flight ability has been reduced to clumsy gliding at best. The birds will have to climb back into the trees when they attempt to glide and miss, but they will also have to start developing better ways to get about in the trees. There will be a die-off as the second generation of trees replaces the first generation, and birds with longer wings will be selected for because they can reach farther to get from branch to branch. The half of the wing that follows the claws will get shorter as the part that precedes the claws gets longer, bringing the wing into a more arm-like appendage. The same pressures will select for longer legs as well, leading to a long-armed, long-legged, clawed bird that spends almost all of its time in the tree-tops. Eventually, it might be necessary for the swamp to begin to return to the rain-forest conditions (as we know, monkeys do not live in swamps {except the Allen swamp monkey, but it dives, so I'm not counting it} for the same reason: nothing to swing from/to) which will provide the hoatzin 2.5 the structures needed for flightless, grabby locomotion. The end result will be the hoatzin 3.0, a feathery, egg-laying creature with long scaly legs,and long arms with claws at the ends that swings through the jungle almost like an ape. If you then wanted the hoatzin to evolve into a human-oid, you need simply follow the ape-to-human evolutionary track.
Granted, this all involves a lot of time, a lot of things happening just right, and a lot of assumptions, like that the trees the hoatzin eats would survive this kind of change long enough for the hoatzin to switch foods, but it is, in theory, given ideal circumstances, possible.
Answer: Quick note: Only hoatzin chicks have claws on their wings; these claws are lost after maturity.
What pressure could lead to further development of claws? Well, it appears that the claws have emerged because of the pressure of local predators. Hoatzin chicks will run away from the nest when the alarm call is given, using their claws to climb more effectively. They'll also drop into the water, then use their claws to climb back up to the nest. Thus once the chicks are able to fly, they no longer exhibit the behavior that encouraged them to emerge in the first place. You'd need a use for those claws in adults to encourage them to be retained and developed further.
Perhaps a flightless species of hoatzin might develop a need for hands for the same reason primates have them - climbing and gathering food. Finding a food source that benefits from more dexterous tools than just a beak might be a good stimulant for such a change as well.
Answer: As pointed out the real question isn't how to further develop the claws, there is plenty of pressure for that already, climbing helps them in many ways. What you need to do is remove the pressure to keep flight capable wings. to really push it you could have them increases in size, the bigger they get the less flight is going to be achievable.  Lack of predators could easily do both, a mass extinction freeing up lots of niches and killing off all the large predators would be enough.
One interesting feature, the creature will have 3 fingers, birds lost the 4th and 5th finger long before they were birds.
Answer: "Whose only remarkable trait, other than looking fabulous, is that their wings have fingers"? I'd have to heavily disagree with you there- Hoatzins have a couple of other remarkable traits as well. The Haotzin is the last surviving member of an order of birds which recent genetic studies have now shown branched off in its own direction more than 64 million years ago, literally as the ashes were settling shortly after the extinction event which wiped out the non-avian dinosaurs. And their most remarkable feature, IMHO, isn't the fact that juvenile Hoatzins possess finger claws.
Even more notably, the Hoatzins are the only birds to have ever evolved a digestive system which utilizes bacterial fermentation to break down the vegetable material they consume, in the same manner as cattle and other mammalian ruminants do. In the place of the mammalian ruminants' rumen (a specialized stomach for bacterial fermentation), in a case of parallel evolution, the hoatzin has evolved an unusually large crop instead, folded in two chambers, along with a large, multi-chambered lower esophagus. Its stomach chamber and gizzard are much smaller than in other birds. Their crop is so large as to displace the flight muscles and keel of the sternum, much to the detriment of their flight capacity.
And you might also be interested to know that the fossilized remains of an extinct species of Hoatzin has been found in Namibia, some 18 million years ago, proving that indicating that, in the African-South American interchange which faciliated the colonization of South America by new world monkeys, rodents, bats and other species, at least a few Hoatzins went the other way and successfully colonized Africa too (along with at least one species of terror bird). As such, full flightlessness seems like an extremely likely evolutionary path for the Hoatzins to take.
So, how's about this for a scenario; over in Africa, as the climate gets increasingly arid, and the mangroves and rainforests begin to be replaced by savannah, instead of simply dying out as they did, some of these African Namibiavis Hoatzins manage to cling on by abandoning their arboreal lifestyle and adopting a more terrestrial lifestyle instead; rapidly losing their flight ability in the process, and becoming fully terrestrial. Their unique pseudo-ruminant digestive system bestows them a tremendous evolutionary advantage as avian browsers and grazers, potentially enabling them to outcompete contemporary ostriches.
And without the limitation to their maximum size imposed upon them by retaining their vestigial flight ability, with their far more efficient digestive systems granting them access to more nutrition, and with the considerable evolutionary pressures placed upon them by African predators, these African hoatzins rapidly grow to become far larger than even ostriches; large enough to rival the mass and height of the largest ruminants, the giraffes (which they could also conceivably compete on a level footing with), and feasibly, even some of the dinosaurs of old (with mummified hadrosaur remains indicating that they also possessed enlarged crops most closely resembling those of Hoatzins). As a result, these end up looking something like this;

The original purpose of these Hoatzins' finger claws, for climbing, has long been rendered redundant by this stage. But these African Megahoatzins still re-evolve arms, and refine their finger claws, in an evolutionary development paralleling those of the gigantoraptors, ground sloths and calicotheres when they all took the same evolutionary path. Equipped with increasingly large and developed claws, they use them to strip leaves, tear off branches, and as potent and formidable defensive weapons against any predators who attempt to attack them or their nesting sites.
Perhaps even also as legs, with a sub-order evolving to become semi-quadrupedal as an adaptation to ground-feeding grazing, just like hadrosaurs did; with this semi-quadrupedal stance also enabling these Megahoatzins to become larger and heavier still, conceivably rivaling the size of the largest ornithopods. What do you reckon; does it sound interesting?


What consequences can a legal non-citizen 14 year old face if he applies for a credit card using someone else's SSN without permission?

Question: I did this when I was 12, and I didn't know what this all was. My 12-year old mind was still working like a 6 year old. One day a letter came to my house saying you are not eligible or something, I can't remember. My dad found out about this and I was given a big punishment and he told me everything SSNs and credit cards. I did not do anything illegal since then. Am I in trouble? I am a legal immigrant but not a citizen in the US. I did not actually get any money and the owner of the SSN didn't get affected in anyway, so what is going to happen to me?
Answer: The fact that you committed what would probably be a crime if committed by an adult when you were 12 doesn't in and of itself have any consequences unless you are prosecuted for an offense before the statute of limitations runs. And, to the extent that it is a felony (this might very well be only a misdemeanor or a juvenile offense that has a statute of limitations because it is a juvenile offense in most jurisdictions), some states (e.g. Virginia) don't have a statute of limitations at all.
The fact that the application was denied and no harm was done to anyone likely severely reduces the seriousness of the offense, so it might only be a misdemeanor if it was committed by an adult.
Certain kinds of adult criminal convictions make people who do not have U.S. citizenship deportable, although ICE doesn't always manage to deport people who are eligible for deportation on this ground.
Subject to special exceptions for certain offenses which aren't applicable here (e.g. murder), a 12 year old cannot be prosecuted as an adult offense in any U.S. state or territory. Applying for a credit card with someone else's Social Security number without receiving any economic benefit, is almost surely not an exception, to the bar on prosecuting someone as an adult for offenses committed when 12 years old.
This means that any offense would be a juvenile delinquency prosecution, which involves a secret trial without a jury, much shorter sentences for the same offenses (that would be served in a juvenile detention center rather than an adult jail or prison if incarceration was ordered), and the sealing of the record of the conviction when you become an adult.
A juvenile delinquency adjudication (i.e. conviction) does not make you deportable the way that many adult criminal convictions do, but they do have to be disclosed on immigration forms such as applications for adjustment of status to permanent residency (I-485), and applications for naturalization (N-400) and once juvenile adjudications (i.e. convictions) are disclosed:

They can be used to bar a finding of "good moral character", which is
  a requirement for naturalization and other forms of relief from
  deportation such as cancellation of removal. Also, as a discretionary
  matter, Immigration Judges can view juvenile activities as a negative
  factor when considering any application for relief from deportation.

Generally speaking, if you do gain U.S. citizenship, you can't be deported for crimes committed prior to obtaining U.S. citizenship.
There are very narrow exceptions for inaccuracies in citizenship applications that can lead to revocation of citizenship, but a failure to disclose in a citizenship application the fact of having purportedly committed a non-violent, regulatory offense (i.e. one that doesn't harm anyone), as a 12 year old, that does not result in a juvenile adjudication (i.e. conviction), would not be grounds for revocation of someone's U.S. citizenship.
Realistically, if no one has commenced a juvenile delinquency prosecution in the last two years, no one ever will. So, you should forget about it and not mention it.
Answer: According to UNICEF:

In the US, the age of criminal responsibility is established by state law. Only 13 states have set minimum ages, which range from 6 to 12 years old. Most states rely on common law, which holds that from age 7 to age 14, children cannot be presumed to bear responsibility but can be held responsible.

So it appears that you could be prosecuted for fraud, but the prosecution would have to show that not only did you do the fraudulent act, but that you were sufficiently mature to be held responsible for it.  Your comment "My 12-year old mind was still working like a 6 year old." suggests not.
In practice, if this was two years ago and you have heard nothing yet, there is very little chance that anyone will care.  (There is also a principle of limitations which says that after a certain time has elapsed, crimes cannot be prosecuted.)
Answer: It very much depends on the country, but there is a big difference between a 12 year old and a 14 year old doing something. If you did this two years ago and haven't been prosecuted or had a visit from the police, you are most likely fine.
In your case, nobody has noticed that something wrong has happened. Someone applied for a credit card, and was refused. Happens thousand times a day. So nobody will ever know you did something wrong unless you tell them.
If you used your dad's SSN, and you had got the credit card, and spent money, then most likely your dad would have repaid the money out of his own pocket and covered for you. (Instead of being in trouble with your dad you would have been in really, really big trouble with him). Still, nobody other than your dad would know about it, so no trouble with the law.
Again: Nobody other than you and your dad knows that you have done anything wrong. If the police knew, then (a) I wouldn't be sure at all that this would be a felony since it never got to a stage where the slightest damage was done, and someone would have to prove that you intended to get money and not pay it back. (b) you were twelve at the time, which makes a huge difference. (c) it would be almost impossible to prove. Even if your dad told the police and it went to court, it would be your word against his. So nothing is going to happen.
Comment: An "SSN" is particular to the USA so that would be the country. The age for criminal responsibility varies in the U.S. (usually 18 for adult offenses and varied but much lower for juvenile delinquency charges, but at least one outlier is 19 and there may be a few other exceptions). There are also some offenses in most states where one can be charged as an adult younger than other offenses.
Comment: Isn't this a felony? So won't I go to juvy?
Comment: @Cooldude123420021811 Who is going to put you there?
Comment: What is the age for criminal responsibility in the US?  Does it vary by state (or offense)?


What is exactly bug in the requirements?

Question: I've just looked for a formal definition and haven't found one.
The term - "bug in the requirements" was always confusing for me, what does mean exactly?
Comment: Someone closed their requirements folder and a small fly got caught between pages. The programmer reading the requirement mistook the fly as a decimal point.....
More often than not, its not a fly between the pages to blame.....
Comment: @mattnz And when you find one, you're supposed to tape it down for posterity: https://en.wikipedia.org/wiki/File:H96566k.jpg
Answer: "A bug in requirements" could refer to one or more of the following (more may exists though...):

A requirement provided by the end-user that conflicts with another requirement or constraint. Example: The user wants to email all customers but does not want the system to collect customer emails.
A requirement provided by the user and not flagged by the business analyst as not feasible for a given project. Example, I want the system to automatically fix addresses of my million customers when the user pushes a button.
The user passes a wrong business fact to the business analyst. Example: A wrong formula to calculate profit.
The analyst captures wrong information or makes false assumptions and considers those as true requirements that need to be implemented.
An incomplete requirement provided to the business analyst that led to a bug in implementation. Example: The user says to the analyst "We only record a customer when a sale is made". A developer getting this requirement may end-up creating a DDL rule that makes the relationship of customer and invoice mandatory such that when an invoice is deleted  the corresponding customer information is also deleted. Unless the developer and business analyst confirm with the user that this required, this searing may be considered as a bug in requirements (and development).
A bug in requirement could occur also when the user and the business analyst miss an entire business function. Example, when the user does not specify security requirement and the business analyst does not ask about this requirement. When such a system is completed, it may not be usable because it is not secure enough.
Answer: It means the requirements were wrong, somehow.

missing something critical
conflicting requirements
incorrectly stated requirements

In non-technical language, this is also known as a "mistake" ;)
Answer: Well there might be two large cases:

The requirements do not represent what exactly the business owner wants; they do not model the business flow.
The requirements are not consistent; this can, or cannot be a consequence of 1.
Comment: I think 1 is a case of bad requirements, not a bug in the requirements.
Comment: @Yosi In case a software system does not behave as intended you have a bad software system or bug(s) in it?


Are there standard vibration and shock specs for shipment of a product?

Question: Suppose I want to ship my product via UPS, or whatever other professional carrier service. What vibration and shock forces should I design my product to withstand? And how can I effectively test my product against those forces?
Comment: A low-tech solution for testing is to package up one unit (or a surrogate, if each unit is very expensive) and then spend a couple days literally kicking it around the office. This should approximate the likely experience of its being handled by parcel or freight carrier staff.
Comment: Jokes aside, is the product exceptionally fragile and also exceptionally valuable (on a per-delivery basis)? Package design does involve some engineering, but I'm having trouble imagining when it would be approached in quite this fashion. I would expect it's done to reduce known loss rates once substantial experimental data is already available. Are you sure you want to design your product in a way that depends on the nature of the shipping carrier?
Comment: @Air The engineering that goes into good packaging should not be underestimated and for many product, changes made to the product to withstand the distribution environment are not unusual especially when  adding packaging would add more to the overall cost than the cost of making the product more robust to the shipping environment. Remember, the customer typically discards the packaging but keeps the product. Any improvements to the product stay with the customer over the life of the product, improvements to packaging do not.
Answer: When I have received fragile content in the past it has always come with a Shockwatch label attached to the side.  I'm not 100% sure, but I believe there is some sort of guarantee by the shipper to keep the forces below the level registered by the label (a guarantee which most certainly comes at added cost).  Looking up the specs in the link above, these labels activate if the shock parameters are above:

Force: 25-100 G
Duration: 0.5-50 ms
Tolerance: $\pm$15%

These ranges indicate the range of labels available and the tolerance indicates the tolerance once you choose a set of parameters.  If you can design the packaging to handle 100 G for 50 ms, then you should be in the clear.
Comment: The Shockwatch labels are interesting, but there are some problems. One is cost, they're about $3 each if you buy them 50 at a time. I don't know of any carriers that provide any sort of warranty with respect to Shockwatch. I do know that FedEx specifically calls out that they are NOT liable should damage be indicated from such a label. The labels also don't say anything about vibration. Damage due to vibration is not at all unlikely and would go completely undetected by the label. The main purpose of these label is to act as a deterrent, but they're really a dog with no bite.
Answer: UPS has, or at least had when I was transit testing packaged products, a specific packaging test standard based on ISTA standards and ASTM D4169. There's also a MIL-STD, 810 something, but I don't remember the exact number.
Typically, for a parcel carrier, the test, regardless of standard, consists of environmental conditioning, a "10 pt" drop test and a vibration test.
The environmental conditioning typically represents the extremes of what would be expected. In our case, we conditioned products for 12h @ +150F and -30F with uncontrolled humidity. The referenced standards discuss other conditions such as a high humidity environment.
The height of the drop is determined by the packaged weight. The product is dropped onto a rigid surface without inducing any vertical motion as follows:

The bottom vertex of the carton which includes the carton seam.
Each of the three edges radiating from that vertex.
Flat on each of the 6 faces

Following that, the product is subjected to random vibration (typically 0.52 gRMS) for 1 hour on each of the three axes with a vibration profile according to ASTM D4728, ISTA or a profile developed from data collected by monitoring your particular distribution stream.
As to what forces you design your product to withstand dependent on a lot of things, mainly what's the cost of product breakage? What are the specific stages of getting your product to the customer? How much does it weigh? and so on. How much engineering and money are you willing to put into the packaging to protect the product? Can you make the product itself robust to transportation, or is it delicate and requires significant packaging? Like most engineering undertakings, it's a tradeoff and there's no one good answer that applies to all products. I recommend looking at the referenced standards, and using those as a guide.
If you want to get testing done without buying a test lab of equipment, there are plenty of labs across the country that will help you develop a test plan and perform the testing. I have personal experience working with Lansmont, they make packaging test equipment, perform testing in house and provide consulting on packaging design. (Note: My relationship with Lansmont is strictly as a prior customer, I have no personal, financial or other ties to them). They are great to work with. UPS also has a test lab and provides packaging design support.
I could go on and on about this stuff, but this is already long enough. If you have more questions, want further information or clarifications, I'll be glad to answer them.


Detect broken blocks that don't drop items

Question: I'm trying to make certain aspects of survival more "painfully realistic" using command blocks. One of those things is that I'd like mining through stone (or other hard objects) with your bare hands to inflict damage on you. I thought this would be as easy as setting up a stat.mineBlock score and, whenever someone mines stone, if they have an empty hand, give them instant damage effects. Unfortunately, it seems the mineBlock stat only increments if the block drops an item, and mining stone with your hands doesn't drop any items. Is there another way to go about detecting when a player has destroyed a block, even if it doesn't drop any items?
Answer: It might be laggy, but you could try execute, clone, and testforblocks to detect changes in the player's environment.
Answer: Testing for a player in a spesific coordinate
Set up a dummy objective:
 /scoreboard objectives add NotHoldingItem dummy

On a clock (or just before you want to use the testfor), in this order, run the following commands:
 scoreboard players set @a NotHoldingItem 1
 scoreboard players set @a NotHoldingItem 0 {SelectedItem:{id:minecraft:iron_pickaxe}}

The commands above set everyone's NotHoldingItem score to 1, and then set it back to 0 for everyone holding the item, leaving only people not holding the item with a NotHoldingItem score of 1.
You can then test for people who have a NotHoldingItem score of 1 (do not have the pickaxe) near a certain block:
/testfor @a[x, y, z, score_NotHoldingItem_min=1]

Testing if where a player is looking at
The first value is the horizontal rotation (ry).

Horizontal rotation values vary from -180.0 (facing due north), to -90.0 (facing due east), to 0.0 (facing due south), to 90.0 (facing due west), to 179.9 (just west of due north) before wrapping back to -180.0 (thus horizontal rotation values increase with rotation to the right, or clockwise viewed from above).

The second value is the vertical rotation (rx).

Vertical rotation values vary from -90.0 facing straight up to 90.0 facing straight down (thus vertical rotation values increase with rotation downwards).

So to test for someone looking 45° upwards (±10) and to the northeast (=135±22)
testfor @a[ry=-113,rym=-157,rx=55,rxm=35]

for a player looking south you can do something like:
testfor @a[ry=22,rym=-22]

Combining these
when you would comebine these two testfors after having setup the scoreboard, you can simply use these to test for a player standing on a certain block and if the blocks he is looking at is the block you want to check.
testfor @a[x,y,z,rx,ry,rxm,rym,score_notHoldingItem_min=1]

Problem
this means you need two command blocks for each point of view to each block. In other words: you don't have enough space in a minecraft world to test each posibility. for testing one block within a void area (an area in which there are no blocks exept the one you want to test) you need to have 2 comand blocks for each block in a 9x9x9 box in which the block to be testet is in the middle
((9x9x9)-1)x2 Command blocks = 1456 command blocks

I think this awnsers you question as a: No, you can't do that...
Answer: The closest thing I could think of is if you use a stone monster egg block instead of regular stone. You could set a command block up to a clock that kills silverfish every time they spawn. Then, if the kill command is executed (you can test for this by putting a comparator next to the command block), you can deal damage to the player.
This wouldn't really work as well since the monster egg blocks have a different durability than regular stone, but I'm pretty sure this is the only way possible as of now. Mojang, pls fix your objectives :(


To what move depth should you analyze a chess position

Question: I'm trying to learn a chess opening and using a chess engine (stockfish8) to analyze the position but I'm wondering what move depth should I set it to (e.g., 25, 30 35 half moves).
Comment: As much as you can afford.
Answer: Generally, the only reason running a chess engine at less than maximum power are time constraints or if you want to give yourself a chance to win, though in the latter case I'd still prefer to play human players instead.
Regarding the use of a chess engine to analyze the position in an opening in order to learn a chess opening I am wondering how you are going to practically do this? I mean, the engine will give you only a certain sequence of moves which it considers best play for both sides. It will not teach you the ideas/plans behind an opening which is the most important part and something which you can rely on if your opponent for instance does not play the expected move. It will not teach you about subtleties, like move-order changes or any sidelines.
I am not saying a chess engine is completely useless for studying openings. You could use it for practice games in a specific opening or you could study a certain alternative move in an opening (but that would be at a stage where you already know the opening somewhat).
For studying a new opening I'd find much more useful than an engine:

any explanation of plans/ideas (this can be books, videos, or a coach/friend)
a database
following games of a Grandmaster who is playing the opening regularly (let them do the difficult analyzing part...)
Comment: @ToddM I'm afraid you're the one who doesn't know what they're talking about. GMs/elite players already know their openings quite well. In their opening prep, they will normally come up with their own ideas/plans, and then test them against the computer. They don't just trust the computer 100%, following the lines it spits out blindly. They reflect, test, and try to understand the positions arising. They do this since they're in constant need of finding "new" stuff to get an edge from the get-go, since their opponents are difficult/impossible to beat from a balanced middlegame/endgame.
Comment: @ToddM Your question was about *learning* a chess opening. I am sure Anand and other GM do know their openings. If you wanted to ask about how GM, IM.... use computers, why didn't you ask that?
Comment: Frankly, you don't know what you're talking about.  All chess masters, international masters and grandmasters use chess engines to study the openings.  My question concerned how they do that. I mean I know Anand is known to use link multiple computers together to garner analyses that go to great depths. My question concern what average.
Comment: Alll grandmasters, international masters and masters use computers to study openings.  My question was how do they do this?
Answer: I don't torture engines much when preparing openings as it makes almost no sense. I grew up from this.
No human can get anywhere close to engines in dynamic positions. That means your moves will be quite random in sharp positions and your opponent's will be also quite random (or very unprecise if it sounds better to you). There is also quite a little point in analysing static position to extreme depths. What for, does it mean something to improve by 3 centipawns on depth 40?
The engine evaluation may be based on some alien variation club players will never make playing unprepared. Evaluation of main line isn't important at all if it is almost certain that it won't happen. And that is exactly what engines expect, 100% precision. Engine will go to a minefield for one centipawn, not caring any mistake means immediate loss.
I doubt it makes much sense for grandmasters and I'm pretty sure it makes no sense for hobby players to waste time and electricity for calculations they will never be able to replicate at the board. If the line is too messy, you will either not be able to find correct moves at the board (if engine didn't see it early enough) or you will simply forget it sooner than you will be able to catch there someone unprepared (if you try to remember it by heart). I think people heavily overestimate use of deep engine searches for practical games. They behave like if it was 30% of a success while it may very well be 0.2% of it.
And here is beautiful example from last round of republic championchip where I had to win with white to make silver and my opponent (very dangerous 2500 player with sharp PC preparation) caught me unprepared in dragon sicilian and from engine perspective he just murdered me with black right from the opening.
<code>1rr3k1/4pp1p/3p2p1/q2P1b2/2BQ2PP/1P3P2/2P5/2KR3R b - - 0 24

1...Bxc2 2.Kxc2 Qa2+ 3.Kd3 Rxc4 4.bxc4 Rb3+ 5.Ke4
</code>
After the game he told me that he knew taking on c2 leads to very good endgame with queen and five pawns against two rooks and four pawns. I didn't know anything so I had to make my decision at the board. Do I want to give a queen and suffer in this type of endgame or do I like to go with my king to the center? I was thinking about half an hour and it looked to me that marching king to e4 could be very easily winning position (maybe I found the only forced draw,  I don't remember that exactly, but for sure I saw no single worse position for me in this variation). I made my march to e4 instead of giving up a queen, my opponent spent remaining 40 minutes calculating. I spent another twenty minutes of his time too, then I went to look on cups and medals as I was almost certain I'm winning (or at least not losing). Neither me nor my opponent found the -10 winnig strike for black that Komodo found on depth 5 in a few miliseconds. In the game I easily converted my extra rook as my opponent missed also the only forced draw (not completely obvious too) and the rest of variations were just easy wins for me.
Even in a dream scenario things can go really wrong. It is horrible strategy to go into a minefield for a few centipawns which is exactly what engines do. They don't help you in recognising minefields, they don't care about them. There is some value in doing deep searches, one can hardly find reason why lower depths would produce better chess related results than higher depths, but that value is very close to zero. It is much easier to measure time related results and they are horrible on higher depths. Even if you are comfortable with wasting the electricity, don't waste your time.
The stronger player you are, the more precision you want, obviously. But with today strength of computers, even GMs should be comfortable on under 1sec for unprobable variations to forget soon and on a few seconds for highly probabe positions to happen. There is always something to do if you want to see depth 50 result, it makes no sense but you can feel pretty comfortable with it, if you can for example prepare a breakfast in a meantime :-)
Answer: The depth of a Chess Engine is the Level of Play when you analyse the game . If you are aware of the ELO System of rating I would like to describe below .

100  - 1000  :--> Beginner
1001 - 1200  :-->  Casual
1201 - 1400  :-->  Average
1401 - 1600  :-->  Intermediate
1601 - 1800  :-->  Experienced
1801 - 2000  :--> Tournament Player
2001 - 2200  :--> Expert
2201 - 2300  :--> National Master
2301 - 2400  :--> Fide Master
2401 - 2500  :--> International Master (IM)
2501 + -2800 :--> Grandmaster / World Champions (GM)

Now when you set the Chess Engine depth to a Highest Level they play with the Strength of an IM/GM . The Depth what you should set is always on the category that you are in this ELO level .
Let's assume that if you are a 1600 Approx Player you must try defeating the Players who are about 1700-2000 ELo level . As you know when you climb up a stair case you should take 1-2 steps at one time and you just cannot leap at one shot you must try crossing the next levels and check where your standard is and then prceed on to the next levels .
Comment: How is this relevant to analyzing chess openings?
Comment: Sorry, but this looks like complete nonsense to me. 1. Different engines have different algorithms. 2. Your classification is arbitrary.
Comment: I have to downvote this answer because you're comparing apples and oranges. Chess programs don't think the way humans do. A 1200 Elo chess program won't think like a 1200 Elo human, even if the ratings are from the same ratings pool (e.g. FICS). The computer may well suggest a bad move even if you're capable of understanding the correct one.
Comment: I like your comment the best as it's the most relevant but do you have a reference for that.  Given computers can get your up to 30 moves in a few minutes, I'm surprised an 11 move depth is considered world class.
Comment: Posted a new answer.
Comment: My answer is quiet abstract to understand . What I mean is that according to the level you are in you should try doing to the next level . You climb level after level . If I ask a beginner to understand the Game level of a GM he will find very difficult to deal with . He will understand some moves and will find himself tangent to the deep & strategic moves of the GM . I have seen beginners fail to understand Sicilian. A master of 2000+ only will be able to understand all the Games . So I believe the depth of a Chess Position should be set according to the classification of the Player himself.
Comment: Well the comparison is not that far as you are saying Apples vs. Oranges but I tried narrowing it down . This is not a one to one mapping as we all know that a Chess rating is somewhat relative . A 1200 player can play the opening level of a GM and a GM can even falter to a 2000 ELO player . Anatoly Karpov once was a victim of it . Even Chess programs somewhat play this particular way . There are many examples as like this so whatever you stated is not somewhat new . So Mr @KefSchecter please reconsider your decision for down voting .
Answer: Sorry to disappoint you but from my Chess experience I can say that when you play real Chess Tournaments or even in the Internet you would find Players of the above category have different way to produce the Openings .
When you play with a Player of 2300 + you would see that his openings are more ultra sharp and much more precise compared to a Player of 1500 Elo level .
The Player with a 2300 + would get an opening advantage very soon and the Score of the Game would be a plus to him . Infact they will even defeat his low rated opponent within 15-20 moves .
A player with 1500-1600 Elo would play average openings with not so great quality but still he can give good competition .
For a better reference please download Stockfish/SmallFish if you have an iPhone and then go to the Game Difficulty Section and choose any one .
PLAY with the APP for sometime and then you would realize the difference .
One more thing : I have given you the answer from a Player's perspective . Please let me know what exactly you are trying to achieve so that I can frame my answer accordingly if the above is not satisfactory .


529 (college saving) account for multiple kids

Question: I have a 529 account for my 3-year-old. We just discovered we're expecting another baby. Is it better to open a new 529 for the new baby or just keep contributing to one and then split it later on?
Comment: If it helps I have 3 girls and each has their own 529 account.  This helps me realize how much each child has for college rather than lumping it all in one.
Answer: With that close an age gap it would probably make sense to use separate 529s. Technically you can transfer funds and even change the beneficiary from one sibling to another, but if both are in college at the same time you would probably want to let both of them use 529 money at the same time.
Also, with multiple accounts you have more flexibility over the investments that each are in (especially when you get closer to college time and want to reduce the volatility in the accounts), it gives each child their own "savings" bank that they can track (and even add to), and it allows for personalized contributions from other family members rather then one big pot that is commingled.
Comment: Thanks, Joe - we approached it from different angles (which is good) and I agree with your points as well.
Comment: A bit better answer than mine. I'd stick to my point, but add (to mine) that if you go the single acct route, to split a year ahead of college for the older child, 15 years out.
Answer: In my opinion, this is probably a personal choice.
With no extra paperwork, you and your spouse can each gift $15000 per child. Unless you are planning to gift more than $30K combined, one acct, to keep it simple, is enough.
If, on the other hand, your total gifting will exceed this, the simplest approach is to use the 2 accounts, and not need to use the 5-year "gift ahead" provision, or credits against your lifetime estate tax.
The 529 I have (in MA) has no annual fee, so aside from a bit of extra paying attention to another account, 2 accounts wouldn't have bothered me.
Last - there are credit cards that offer a 2% cash back right into the 529 acct. We are in the endgame, my daughter a junior in college, and these rewards will have paid for over 3 semesters at her school. Members might object to a products promotion, it's easy enough to search and find this.
Answer: Separate accounts may be better if you live in a state where 529 contributions are deductible from your state income taxes.
OP did not list a state, but you may need separate accounts to claim the deduction for both children.  In Maryland the deduction is "per account"[1] or "per beneficiary", and each account can typically only have one beneficiary at a time.  So you would need a separate account for each child to get the full tax deduction.
[1] https://maryland529.com/basics-of-529-college-savings-plans/tax-advantages-of-529-plans
Comment: Nice catch. In my state, it's a low $2000, so multiple accounts are needed to get the full benefit.
Comment: The $2000 limit is per couple, not per account, so multiple accounts don't really make a difference. (Found that out *after* I rushed to open a pair of accounts before the end of the year following my second son's birth.)
Comment: The mechanics of the limit may depend on the state.
Comment: @wrschneider JoeTaxpayer mentioned in his answer that he was from MA. I was questioning his assertion that multiple accounts are beneficial in that state, as for tax purposes there is no difference between a contribution of $2000 to a single account and two contributions of $2000 each to separate accounts. (In each case, you get a deduction of $2000.) MD, however, sounds like a good state to live in for this purpose!
Comment: @chepner good point, it looks like in MA the limit is per account *owner* rather than beneficiary, so different rules from MD.
Answer: Are there different people that would be interested in contributing for different kids?  This is generally only an issue if your first kid is from a prior marriage/ relationship.  If there is a group of people related to one kid and not the other, having separate plans probably makes it easier for them to contribute.
How concerned are you about equality between the two kids?  If you have separate accounts, there is a risk that one kid ends up with a meaningfully different amount when they start attending school.  If you get a few early bull market years when the older kid has a much larger balance due to having many more years worth of contributions, it's not out of the realm of possibility that the older kid would end up with twice as much as the younger even if you made the same contributions over time.  Similarly, if you're moving the older kid into more conservative bonds when the market rallies, the younger kid could end up with significantly more.  You could move money around if it became clear that was an issue but that can be complicated if the kids are old enough to know about their account.  If you have a single account, you can split it much closer to when you're going to be drawing money out and when the kids are old enough to have conversations about goals (i.e. is the goal to give equal dollar amounts to both, to cover an equal fraction of the expected family contribution for both, to pay for the same number of years for both, etc.) and logistics (i.e. what happens if post-split the younger one sees a bigger rally than you were expecting, what happens if the younger one sees a downturn, what happens if someone wants to take a gap year or if someone wants to go to grad school).  Personally, this is the overriding consideration in my mind-- having one kid get substantially more help because their birth happened to coincide with a better market than their sibling has the potential to create a whole lot of familial strife.
What goals do you have for using these accounts to teach your kids about personal finance?  If you envision, say, encouraging your kids to track their balance over time or to contribute personally to the account (perhaps with a parental match) when they're old enough to earn some money on their own, that's much easier if each one has separate accounts.  If you envision wanting to have conversations early on about making college choices with an eye to affordability (i.e. suggesting they spend their first two years in a local community college before transferring to the bigger school, looking at how much they can save by taking AP/ IB/ dual enrollment classes in high school, talking about realistic budgets and loan amounts if they're looking at Expensive Private U), that's likely easier with separate accounts too.
How much flexibility are you going to want in investments?  From an accounting perspective, it's easier to have separate accounts where you slowly move each one to a more conservative balance as the beneficiary gets closer to college.  You can do the same thing with a single account recognizing that you've got two simultaneous savings goals but it'll be easier for most people to think of separate accounts.
Of course, if you're lucky enough that you'd hit a contribution limit for a single account then of course you'd want separate accounts.  If you're putting away more than $30,000 a year for your childrens' education, none of these considerations likely matter too much because you're going to have more than enough to fully fund both kids.


wp_set_object_terms creates relationship to REVISION?

Question: I have a custom post type, 'albums'.  In it is a taxonomy, 'album_artist'.  I am trying to programatically add artists to that taxonomy using wp_set_object_terms in a function that's hooked into save_post.
function get_album_data($post_id) {
    // CODE REMOVED FOR BREVITY: IMPORT DATA FROM EXTERNAL SOURCE, PARSE VARS
    wp_set_object_terms( $post_id, $album_artist_name, 'album_artist', true );
    update_post_meta ($post_id, 'Release Date', $release);
}
add_action( 'save_post', 'get_album_data', 1001 );

I'm using "true" for those cases where, on a compilation album, there is more than one artist (think "21 Original Hits 21 Original Stars").
Going through the wp_terms, wp_term_relationships and wp_term_taxonomy tables in the DB, here's what I'm seeing:

In wp_terms, the terms are being created properly, with correct slugs (ie "The Police" get a slug of the-police, and term_id 482)
In wp_term_taxonomy, the term is showing up under the right taxonomy (ie term_taxonomy_id 506 has term_id 482 with a taxonomy of album_artist)
In wp_term_relationships, term_taxonomy_id 506 shows with object_id 2448

Looks good, right?  Sadly, no.  Because object_id 2448 refers to POST 2448, which is actually a REVISION of 2447.  And when I check the wp_postmeta table, the 'release_date' meta has been updated on 2447, not 2448.
So WP seems to be creating a relationship to the wrong post.  That's why, I assume, the artist isn't showing up on my album page the way it would if I went into the "Artist" metabox and clicked the checkbox that says "The Police".
And yet, it seems to treat the $post_id variable differently in a update_post_meta versus a wp_set_object_terms.  Because the two statements literally are adjacent to each other in the function, yet the $post_id variable means different things to different functions.
How do I force WP to make the relationship between the terms and the PARENT, instead of the revision?
Answer: Use wp_is_post_revision() function which will give you false if post is not a revision (in which case just work as usual with that) or actual post ID to use instead of revision's.


Names of Allah Is it written Correctly

Question: Can we write Allah's Name, Without "Al" before that Name? Example is writing "Qayyoom" instead of "Al-Qayyoom" This question arise because somebody has written only "Qayyoom" and mention that it is a Name of Allah.
Answer: Qayyoom is an adjective, it is not a private name. But Al-Qayyoom is a private adjective which refers only to Allah. Just like Ar-Rahman, Ar-Rahim, Al-Bari etc.
Ilah is the word in Arabic meaning god. You can claim that Zeus was a god, or Uzza. This won't be wrong literally. But Al-Ilah (Allah) means "one true god". It is like "The God", which is the one, everyone understands that you are not mentioning Zeus or Uzza.
Qayyoom is of the same type with merciful, but when we say All Merciful, we mean Allah.
Thus, you should put Al, if you want to refer to Allah.
Answer: If you speaking Persian or Urdu you can omit the article. If you are speaking Arabic you do not omit it.
Comment: I have mentioned my question only about writing Allah's names in English

Names of Allah Is it written Correctly


Why was Tom Bombadil left out of the LOTR movies?

Question: Tom Bombadil among others played a significant part in the books but were left out in the movies. Was this just to save time?
Comment: Um, you might need a better definition of "significant" then. ;-)
Comment: http://scifi.stackexchange.com/q/123991/31029
Comment: @OceanKnight I doubt he's known by *anyone* who hasn't read the books. He's a pure LotR thing whose significance doesn't go beyond being a mystery and LotR fan favourite because of that mystery. Which is why only LotR fans would ever complain about his absence and everyone else couldn't care less. But that just as a general remark. Don't get me wrong, it's not a bad question at all.
Comment: @NapoleonWilson I understand what you mean, he's not central to the plot and can be taken out without the story falling apart. He is however an iconic character who is even know by people who have not read the books.
Comment: @NapoleonWilson He is definitely better known by fans of the books for obvious reason. However a friend of mine who has never read the books (no patience) and is into fantasy still knows of Tom Bombadil.
Answer: Tom Bombadil as a creation precedes much of the LOTR mythology. He appears first in a 1934 poem "The Adventures of Tom Bombadil", where he is a "'merry fellow' living in a small valley close to the Withywindle river, where he wanders and explores nature at his leisure." (https://en.wikipedia.org/wiki/Tom_Bombadil).
Bombadil does not really fit into the LOTR mythology, at least, there is very much discussion where to place him exactly: http://tolkien.slimy.com/essays/Bombadil.html
So he very often gets left out in adaptions, as he doesn't really fit in all that well.
More to the point, the director Peter Jackson is quoted as saying that, while he first had plans to use Tom Bombadil, he left him out because he didn't advance the action: "the Bombadil sequence has so little to do with Sauron or the Ring, it is difficult to justify the screen time. It simply doesn't give us any vital new information."
http://www.theonering.com/complete-list-of-film-changes/the-fellowship-of-the-ring
Comment: And if Peter Jackson says something can't justify the screen time...
Comment: @Joe To be fair he did leave out the entire return to the Shire which most fans argue was worth the screen time moreso than, say, an hour of Frodo and Sam bumbling around in a swamp, or six consecutive ending scenes in RoTK...
Comment: "it is difficult to justify the screen time", but we're gonna make a movie **trilogy** out of this other 330 pages long Tolkien book.....
Comment: @Kevin Again to be fair PJ only wanted to make it two movies but the studio said it was three or none.
Answer: He didn't play a signficant part in the books. In terms of plot pacing, his role was to provide a little bit of down-time between the tense times of Old Forest, and the Barrow-downs .
Tolkien's style of plot pacing was that after the characters go through some trial, there should be a relaxation period before the next trial.  (This is very common in film and print).
So in the book, we had:

Crickhollow (relaxed)
Old Man Willow (tense)
Tom Bombadil (relaxed)
Barrow-wight (tense)
Tom rescues Frodo, and segue to Bree (relaxed)

The first film actually uses similar pacing but skips one cycle:

Meeting Pippin and Merry (relaxed)
Black Rider chase scene (tense)
Reaching the ferry, segue to Bree (relaxed)

To keep with this pacing pattern, if the film included Tom Bombadil after the Black Rider Chase, it would have also meant including another scary scene such as the Barrow-downs. From this point it is speculation; but the scriptwriters must have felt that adding these two scenes would either add too much running time, or take the viewer too far away from the main narrative.
Comment: The Barrow-downs scene should really have been included.  Or perhaps some kind of barrow or room found at Weathertop to give the Hobbits their weapons, rather than Strider simply dropping them in a pile.
Answer: Screenwriter Phillipa Boyens explains in the extended edition documentary that the central message they wanted to emphasise with respect to the one ring is that no-one (not Gandalf, Aragorn, Elrond - not even Frodo at the end) can resist the lure of the ring. Then, along comes Bombadil and it has absolutely no effect on him. Including the Bombadil sequence undermines that message about the ring.
Comment: It also serves as a distraction; now viewers are wondering who this Bombadil fellow is and when he will swoop in to save the day. Moviegoers are very conditioned to expect Great Things from Unique People such as someone who is the only character not affected by the Great Evil.
Comment: @TylerH Chekhov's merry immortal
Answer: I will add my bit.
Tom Bombadil adds excitement and appears significant because the book through this point has been dreadfully boring.  That may be too harsh, but the first half of The Fellowship of the Ring moves along at a glacial pace.  The two almost-encounters with the Nazgul are really the only action and are very brief.  Old Man Willow is the first real extended action in which the hobbits fare poorly and only Tom showing up and rescuing them saves the day.  The scene in the barrow downs is also quite exciting and the hobbits once again fare very poorly and only Tom showing up and rescuing them saves the day.
So the first two episodes of excitement and suspense are both entangled with this great and mysterious figure, and comes to mind prominently in the minds of readers.
In the narrative of the overall story, however, Tom really isn't that significant in moving the story along.
Comment: Are the down-votes because I dare speak negatively of the holy trilogy, or something more constructive?  I actually love the books and have read them multiple times and will probably start them again soon.  But it is always a slog to get to Bree.


When should I use spray-on versus wash-in waterproofer for treating DWR garments?

Question: There are both spray-on and wash-in products available for treating my DWR (Durable Water Repellent), gore-tex, eVent and other garments using products such as nikwax wash-in or nikwax tx-direct.  What types of garments is it more appropriate to use spray-on versus wash-in on and vice versa?
Comment: I'm not sure there is much of a difference, they should both reapply the DWR. I suppose the wash on ones are more likely to get every part of the garment? In my experience neither are ever as good as the factory added DWR.
Comment: That said, I'd imagine getting the DWR on the inside of the jacket would actually work counter to the processes [that Gore tex relies on to work](http://outdoors.stackexchange.com/questions/40/how-do-i-wash-gore-tex-clothing/5010#5010). In short I don't know.... :D
Answer: After considering the existing answers and doing some additional research, here's my take:
Spray-on waterproofing
Spray on waterproofing should be used on Multi layer garments. You only want to treat the outer layer which reduces the chance that it will be 'wetting out' quickly, which allows the inner membrane to maintain it's porous properties.  I've found many references for gore-tex which state "We do not recommend wash-in treatments, as they can hinder your garment's breathability."
Wash-In waterproofing
Ideal for Single Layer waterproof or water resistant DWR fabrics. Probably great for your tent's rainfly, cheap rain shell pants, or your single layer packable windbreaker.  Not so good for your multi-layer gore-tex jacket. Though, you could probably use the spray-on coating for these type of materials as well with little difference in final result.  So, if in doubt, I'd use the spray-on.
Either way, you should keep your garments clean to ensure that body oils and sweat deposits don't clog the pores in the breathable membranes. Most breathable garments recommend using a detergent free tech wash that won't wash away the DWR treatment.
Comment: The Nikwax wash-in products were directly recommended to me for use on my Gore-Tex 3-layer shell by professionals at multiple local outdoor stores. But TBH I did not have the best experience using them...
Comment: I personally only have ever used spray-on waterproofing. But not because I knew what I was doing! ;-) Rather because of ease of use. But now it's good to know there's a valid reason for it too.
Answer: Contrary to what a lot of people are saying, the wash-in treatment won't block pores of multi-layer fabrics (unless it's really dirty).
The chemicals used are designed to break down particulates as small as possible. The 'wash-in' also doesn't do a whole lot of actual waterproofing on the fabric, since it's soaked in water itself. It simply removes dirt and helps the fabric to do its job better. Your jacket will even look like it's been soaked through (because it has!) after being washed.
Tumble drying on a low heat will re-activate the garment by expanding the fabric, and making the pores 'smaller' and more one way. Obviously if the fabric isn't clean, it's not going to do as much, since the pores are blocked.
The spray on is a totally different bunch of chemicals, and would block pores! It is essentially a water repellent.
This is best applied to a dry jacket and spread around with a small cloth or sponge (note that this material will also become water repellent), and left to dry or tumble dried on low heat. Extra should be applied to high wear-and-tear areas, such as the shoulders, neck and cuffs.
This lay will be rubbed off over time, and should be applied about 3-5 times in between washes.
-Source: Worked at a company making such stuff.
Comment: Your first paragraph on "wash-in treatment" seems to me to be describing *tech wash" for cleaning away dirt or detergent. The question is about wash-in *treatment for waterfoofing*. Please clarify.
Answer: I have garments, such as pertex, with a pile (Buffalo Mountain Shirt) or microfleece lining (Rab Vapour Rise Jacket). It's useful to have a DWR treatment on the Pertex to help with water resistance where the lining still needs to cope with excess moisture.
In these sorts of garments you definitely want a spray-on treatment otherwise the action of the lining allowing it to move excess moisture away from skin or base clothing will be compromised if they also become hydrophobic due to the DWR.
For clothing with no such lining where you ant all the garment to be water resistant (or waterproof), then the wash-in sort of DWR, is more convenient and probably does the job better, too.
Comment: When you say "...where you ant all the garment to be water resistant..." do you include both *breathable* and *non*-breatable materials? Or would the treatment be different for those two different fabrics?
Answer: To emphasize what Liam and Paul hinted at, in all likelihood, too much nikwax wash-in and the like could potentially act against gore-tex by blocking the pores and preventing the fabric from breathing (thus soaking in your own sweat).
What gore-tex primarily recommends on their site and what I've had more success with is simply tumble drying the garment for 20 minutes to reactivate the DWR every once in a while. Every so often, I also coat the seams in otter wax to really seal the deal.
Comment: I would keep that quiet about the Otter wax as WWF/ Eco lobby may be concerned about otters being farmed to collect their Ear wax just to keep your Goretex jacket dry and toasty !
Comment: If you want to "really seal the deal." with wax aren't you destroying the breathabilty?
Answer: From the Nikwax website:
Wash-In
"For the convenience of a wash-in product try:
TX.Direct® Wash-In"
Spray-On
"For non-machine washable items or those with wicking linings use:
TX.Direct® Spray-On"
Answer: Scott has a good point. Nikwax will "Plug Up" Gor-tex and leave you in a sauna (first hand experience). To be fair, The tumble dry works well for a time but there are better options.
Hawk Tools states on their site that their bar wax contains "Tylol" and binds to synthetic fibers. The above discussion Spray on vs Wash-in is so binary. Also, make sure to consider the difference between waterproof vs water resistant here as well. Amazon seems to have some in stock.


What should be done differently for high-gravity beers?

Question: What, if anything, should you do differently when brewing a high-gravity beer?
Answer: First, make an appropriately sized starter! Pitching a regular old vial into something like a 1.090 beer is a good way to overstress the yeast and get lots of undesirable esters, and have a beer that didn't finish out completely.  Jamil has a helpful writeup on pitching rates and a pitching rate calculator that will help you size a starter.
Second, pick a yeast that is known to handle the higher alcohol.
Third, make sure your aeration step is solid.  Your beer will need to be well aerated to ferment out completely.
Comment: Ditto on all of the above. Also expect longer time for your beer to carb up after bottling. Also expect your beer to need to age longer for all of the flavors to blend.
Answer: I'd add to be sure you can maintain a proper fermentation temp, also.  High gravity beers have a propensity for throwing fusels, and if you don't keep the temp down it can exacerbate that.
Answer: By following these steps, you should be able to approach 20% ABV:

As Morgan said, make sure you use enough yeast!
Aerate the beer with pure oxygen at the start of each fermentation phase
Add sugars and yeast during secondary (and/or tertiary) fermentation
Use different yeasts for the different fermentation phases. Yeasts that have high alcohol tolerance don't necessarily like high gravity, and vice versa — start with a yeast that can take high gravity, finish it off with one with high alcohol tolerance.


Do I have to repray Isha due to constant flatulence?

Question: I have this problem of constant gas. I read online that if you have this then you do one wudu per prayer. But sometimes really late at night it can go away. I am not sure specifically what time it goes away. It is just on random days like today. The thing is I have already read Isha, so if it goes away at night then do I have to repray Isha?
Comment: See also: "[Not being able to maintain Wudu during Ramadan for Taraweeh prayer](http://islam.stackexchange.com/q/13362/9123)"
Comment: just put your trust in Allah, that is all you can do. If you gassed during prayer, then you would need to repeat it, apart from that there is no need to. Regarding the gas there is a hadith that tells us not to break our prayer unless we hear or smell it. So if you thought you gassed, but didnt hear anything or smell anything then just continue with your prayer
Comment: Sister if you have already prayed your Isha and then your gas went off, there is no need to pray it again. It is only if it goes off during the prayer that you need to redo your wudu and pray it again.
Comment: but i get gas all day all the time. it is a constant thing. it very rarely goes away and i do not know specifically when it can go away. It is just random. that's why i am so stressed.
Comment: like for example yesterday it went away at 2:00am in the morning. but it only went away for 20 minutes. and i already read Isha before at an earlier time yesterday and I was unsure of whether or not I should repeat it. I was so tired. And I am constantly stressed and thinking about it.
Answer: اسلام عليكم
First off, you need to be aware that there is no such thing in Islam as redoing your prayer because your released gas later on. The moment you finish your prayer, you can release gas or anything else that negates the ablution (wudu).
You only redo the prayer if you released gas DURING the actual prayer.
As far as releasing gas throughout the day, that's either how your body functions or your diet is heavy on spicy, gassy drinks, etc.
I sincerely hope this makes sense. Do comment if you need more clarification.
Allah (SWT) knows best.
Answer:
وَجَاهِدُوا فِي اللَّهِ حَقَّ جِهَادِهِ هُوَ اجْتَبَاكُمْ وَمَا جَعَلَ
عَلَيْكُمْ فِي الدِّينِ مِنْ حَرَجٍ مِلَّةَ أَبِيكُمْ إِبْرَاهِيمَ
هُوَ سَمَّاكُمُ الْمُسْلِمِينَ مِنْ قَبْلُ وَفِي هَذَا لِيَكُونَ
الرَّسُولُ شَهِيدًا عَلَيْكُمْ وَتَكُونُوا شُهَدَاءَ عَلَى النَّاسِ
فَأَقِيمُوا الصَّلاةَ وَآتُوا الزَّكَاةَ وَاعْتَصِمُوا بِاللَّهِ هُوَ
مَوْلاكُمْ فَنِعْمَ الْمَوْلَى وَنِعْمَ النَّصِيرُ
(الحج:78)

This AYA tells us that whatever we are doing as a muslim, if it is difficult for us, we are doing it wrong.
Especially for As-Salat as it is the way to find peace and happiness in our hearts.

The Prophet Muhammad (SAWW) says before doing it أرحنا بها يا بلال
"make us comfortable with it (As-Salat)"

To conclude, repeating salat at night causes you trouble then you must not repeat it.
Note that the Satan wants you to repeat your salat to make it a burden for you, so that you hate your religion. You should not obey him and be patient.

لَا يُكَلِّفُ اللَّهُ نَفْسًا إِلَّا وُسْعَهَا
ALLAH does not burden a soul beyond that it can bear… (Qur'an, 2:286).

You have to pray to ALLAH as HE wants and HE wants us not to have troubles practicing Islam. We should obey HIM.
Do your ablution (wudhu) for each salat and do not worry about anything until InshALLAH you're blessed with good health and your sickness goes away.
And remember: do not give heed to Satan's whispers.
Answer: First of all, you have to know the reason for the constant gas, maybe it is related to the type of food you eat, simply visit a doctor and inshallah you will be fine.
Secondly, you need to have wudu just before the prayer, once you finished your prayer, you can do whatever you want as long as it is Halal


Are some animals, like dogs and cats, color-blind and how do we know that?

Question: I have heard that some animals, including dogs, cats and donkeys, are color-blind. They cannot recognize any color. Is that true? And how can humans verify that animals are color-blind, or not? During evolution, has color-blindness not bothered them at all?
Comment: We can look at the composition of Cone and Rod cells in their retinas and compare them to our own. We can also look at the pigments that they are capable of producing, like Rhodopsin, and get an idea of the wavelengths of light that these animals are sensitive to. These days you could probably do fMRI or EEG studies to see what wavelengths of light generate activity in their visual cortexes.... http://www.cals.ncsu.edu/course/ent425/tutorial/colorvision.html
Answer: TL;DR: We have a good physiological understanding of how eyes work, so by examination of other species' eyes, we can tell a lot about what colours they are capable of seeing.
First, a little bit about the physics of colour
Light is made of photons, and each photon has a wavelength. The distribution of wavelengths coming from sunlight looks like this (wavelengths on the x axis):

Any perceived 'colour' is some sort of summary of the wavelengths of the photons which get into an animal's eyes.
Now, a little about colour perception
There are cells in the eyes which respond to being hit by photons: these are called rods and cones. Colour vision is principally achieved using the cone cells, which have a peak sensitivity at one particular wavelength, and are less sensitive at other wavelengths.
We (non-colourblind humans) have three different types of cone cell, sensitive to photons with wavelengths of 560, 530, or 420 nm, corresponding to the peak sensitivities of three different types of light-sensitive opsins which are present in cone cells. Other types of opsin exist in rod cells (Rhodopsin) and our circadian-rhythm entrainment (melanopsin), but the three different opsins in our cone cells are responsible for our colour vision. Because we have three different types of cone cell, we are referred to as 'cone trichromats'. The sensitivities of the three cone types overlap a bit, looking like this when plotted over the visible spectrum:

When cone trichromats perceive colour, what we're doing is taking the information on how active each of our different types of cone cell are, and using that to infer how many photons there are of each wavelength in the light that hits our eyes.
Of course, cone trichromats can't possibly summarise the whole diversity of wavelengths that are coming into their eyes using just three different measures of intensity - the line is way too complicated to summarise from three points. Also note that for humans, there is no cone cell that is sensitive above about 700 nm, or below about 400 nm. This means that we simply can't see differences in the infra-red or UV parts of the colour spectrum.
How does this all relate to colour-blindness in animals?
It is fairly simple to test the peak sensitivity of a cone cell: you take an eye from a freshly-dead animal, hook up an electrode to a cone cell, and then provide light of different wavelengths, and measure what wavelength causes the cell to 'fire' the most. If you repeat this with a large number of different cells, you can confidently determine how many different types of cone cell the animal has, and what wavelengths those cone cells are most sensitive to. This experiment (or similar ones) has been done for many different species, so we have a good background knowledge of what colours different species are capable of seeing.
Many species, including most non-primate mammals, have only two types of cone cell (i.e., they are cone di-chromats, as against non-colourblind humans, which are cone tri-chromats). This doesn't mean they see no colour, but it does limit the types of colour they are able to see. Many tools exist to simulate the visual ability of cone dichromats, for instance here, or here for browsers without flash support. These tools simulate human vision with different numbers of cone cell types. When comparing across species, it is important to remember that both the number of types of cone cell, and the peak sensitivity of each type, may be different, so the tools do not capture the full range of possible colour-perception abilities across species.
There are also cone tetrachromatic (four types of cone cell) and pentachromatic (five types) species. The record appears to be held by mantis shrimps, which have sixteen different types of cone cell. These species can in principle see a greater diversity of colours than cone trichromats.
Does colourblindness present an evolutionary problem?
Not necessarily. Compared to cone tetrachromatic species, humans are 'colourblind', and it seems to have very little impact on our day-to-day survival. Similarly, most colourblind humans (i.e., with one or more types of cone cell disabled compared to non-colourblind humans) get along perfectly fine - a special test is needed to detect colourblindness in humans. If trichromatic vision gives no particular survival advantage, there is no reason to think that it will be favoured by evolution.
Comment: @AliceD... I think one of us should ask the question, "I live near a nuclear power plant and was bitten by a glow-in-the-dark spider. When should I expect my Spidie senses and web-slinging abilities to kick in?..."
Comment: @AMR: Good point. I've added some detail on the diversity of opsins in our visual and circadian systems.
Comment: Awesome answer. Too bad the best answers typically raise the smallest amount of rep.
Comment: @AliceD I would do it too if I didn't think some of our more humorless compatriots wouldn't vote me down into oblivion. I could even photoshop a photo of a spider bite to have a slightly neon green glow too it, and say I have this sudden craving for stew of Calliphora vomitoria (Blue-bottle Flies).
Comment: If you could add a paragraph on the pigment molecules (opsins) expressed by the cone cells, that are sensitive to light at the three wavelengths you reference and how they enable color vision, it would complete the answer, from a biochemical perspective. Otherwise this answer would be just as valid in answering a question as to how a CMOS or CCD sensor uses a Bayer filter to record color information. Definitely a well researched and informative answer, I just think that tying it to the proteins that cause the cones to respond to color would help.
Comment: @AMR - Now *that* would be a cracker :)
Comment: The colorblind simulation tool linked in the answer requires Flash; nowadays Flash is pretty much dead, so do you know of one that doesn't?
Comment: Cheers for pointing that out. Have added an example that doesn't rely on Flash.
Comment: Might also note that most mammals other than primates are dichromats, while most birds (and I think reptiles) are tetrachromats, being able to see ultraviolet.
Comment: Good point. The OP's examples were all mammalian, so I have added some more background and another citation to this effect. The source gives some background on the evolutionary origins of the opsins in different mammalian lineages.
Answer: Short answer

Dichromats can discriminate colors;
Color vision in animals can be tested behaviorally;
Trichromatic vision is not essential for most animals, but is believed to be beneficial to species relying on fruits (frugivores).

Background
I would like to complement bshane's excellent physiological perspective with a more behaviorally oriented answer.
Firstly, it is quite incorrect to say that dichromats can't see color. "Color blindness" is a deceptive term, since dichromats are not blind to colors, they are "blind" to some. For example, the most common type of color blindness, namely red-green color blindness (deuteranopia), is caused by the lack of green cones. Because of the red-green opponency in color vision, they have difficulties discerning greens and reds. However, they can see yellow and blues perfectly fine. Hence, 2 cone classes are sufficient to recognize colors, but missing a green cone simply results in reduced resolution in the long wavelengths.
Evolutionary, the added cone in trichromats is the medium-wavelength green cone. Trichromatic vision has evolved relatively late in evolution in New World Monkeys and is thought to have been beneficial to them to distinguish between ripe (red/yellow) and unripe (green) fruits, as their diet consists for an important part of fruits (Osorio & Vorobyev, 1996). Noteworthy is that trichromatism is more of an exception than a rule. Nocturnal animals are often monochromats, as rod-mediated vision is beneficial under scotopic conditions. Nocturnal species not only are not negatively impacted by a lack of color vision, they in fact benefit from it, because all of their retinal space is occupied by light-sensitive rods. The photon-hungry color-receptive cones need photopic conditions. Dichromats are the rule, while trichromatic vision is considered exceptional.
We can show trichromatic color vision in animals using behavioral experiments. Animals can be trained to perform color recognition tasks, like Munsell papers, that test the ability of the subject to recognize  red, yellow–red, green–yellow, green, blue–green, blue, purple–blue, purple and red–purple colors. When the subject is able to succesfully recognize these colors, it is safe to say they are trichromats. For example, Munsell papers have been used to show that capuchin monkeys (Cebus apella) are trichromatic (Gomes et al., 2002).
References
- Gomes et al., Behav Brain Res (2002); 129: 153–7
- Osorio & Vorobyev, Proc R Soc Lond B (1996); 263: 593-9


When do you record room tone on set?

Question: I want to ask to see when people feel its an appropriate time to record room tone on set. I typically wait until the end of the day to get all of my room tone recordings, even if I have to run around and record multiple rooms in a single location.
Answer: Sometimes I ask that the Director to wait a few seconds after frame is called by the cam operator. If there's not enough time there. I ask for 15 seconds to 30 seconds of quiet before cut is called on the 'final' take of a scene.
The truth is room tone is mostly used from the takes themselves.. not from the separate room tone recording. The only time you really need room tone on a separate recording is if the ambiance is inconsistent or noisy.
Getting room tone at the end of the day usually doesn't work and a PITA to get.
Answer: I need room tone by microphone angle for dialog editing. I usually make fill with pauses between breaths, but if I can even get 10 seconds per angle, then I'm pretty happy.
A general room tone is really helpful when I'm backfilling MOS shots, then I don't have to try to make a fill from other takes, or the take prior.
A trick that I've been using on sets is pressing the record button, then acting like it takes 3-5 seconds to start my recorder. Everyone stays quiet for that long, so I get a little bit of
fill
Answer: Look up this topic on jwsoundgroup.net, there are several quite long discussions about it by top professionals in the business.
Answer: Flipstar gave a good explanation—I'll add that I've worked with a couple of directors who actually like to have a long silence on set right before the first take of a scene. It's a moment for everyone to relax and think about what they are about to do for the shot. Plus, no one is trying to "pack up silently" while you linger and curse them for every floor creak you hear.
Answer: I was just at a shoot where after the last take the director himself asked everyone to stay in place for 30 seconds for room tone - brilliant
Answer: Well usually what is expected from the director and the other members of the crew is roughly 5-10 sec of silence before the Director says ACTION and 5-10 sec silence after the Director says cut. That's what I request my director to do. Some of them follow, some of them just disregard it and think that everything can be FIXED in post. If you are freelancing and working mostly on indie films (like me), it completely depends on you on how seriously you want the director to take sound. Talk to the director about WHY you need the silence that you are asking for.
Answer: It's very important to establish a routine with the 1st AD (if there is one) as well, as he or she  is most often the one who handles the scheduling of the day and calls the roll. On the first production day, make sure you let the AD know what you need (room tone as well as wild sound) so that recording room tone is an expected and integral part of the day. Asking for room tone when the G & E crew have already started to break down lights and rigging is usually too late.
Another point to make is that the presence of lights, camera and people will (usually subtly) change the room tone, so going back after the fact at the end of the day might not produce the results you need. If you have buzzy HMI lights during every take, that's what you'll need in your room tone. If they're not there at the end of the day, your recorded tone won't match.

When do you record room tone on set?


UV Protection while trekking at 5000m for myopic vision

Question: I have trouble seeing distant things and have myopia. Thus I prefer glasses with my prescription number (which is both cylindrical and spherical). I want protection from UV rays as I am going to spend some time during this trek which would be crossing 5000m. Can you suggest me specific kind of glasses that could help me. I read photochromatic lens might not be good enough.
I don't want to change glass every time so I am looking to explain my local stores to get me a glass with specific properties that have my prescription for myopic vision.
Comment: [This answer](http://outdoors.stackexchange.com/a/7785/2766) should help
Comment: Not really sure what you are wanting here. Most opticians should do prescription sunglasses with whatever your prescription is. You might also want to look at goggles that can go over your glasses depending on what you are doing.
Comment: I think you need to talk to an optometrist, and probably invest in a $1000 pair of shades.
Comment: For a trip where you'll spend a lot of time as high as 5000 m, goggles are probably the best option, because they will also protect your eyes from wind. But my usual solution is photochromatic glasses with cheap removable side shields. You can get a pair of glasses super cheap online from zennioptical.com. I use side shields sold as "sidewear" on amazon by a company called sideshield.com. You can even just use pieces of duct tape on the sides.
Answer: There are several options

Goggles that fit over you prescription glasses (Commonly referred to as "Over the glasses" or just 'OTG'.) - probably the cheapest solution, used successfully by many people.
Contact lenses  are available for all sorts of prescriptions now days and could be worth considering.
Prescription Sun Glasses - good wrap around sports len's will provide enough protection for 5000 Meters. These are expensive, but will be usable for other activities other than snow sports
Prescription lens in Googles - best solution for above the snow line but not cheap and not as versatile as prescription sun glasses.

Talk to to your optometrist as he will be able to offer the best advise for you.


How can I have Apache display a static maintenance page for all but certain users?

Question: I need to be able to put our site into maintenance mode, excepting certain users to allow for QA/Dev to be able to test changes to the site/database during the maintenance mode.
The problem is that the list of IPs will be changing every time we do it and do to policies, we cannot modify the main apache configuration file with a different list of IPs each time we do it.  We can do a one-time modifications of the apache config in order to support reading in or using some other file that would have the exception list.
What options do I have for providing apache with a list of IPs that should not be redirected? Would an .htaccess file that we add do it? What about a file of key value pairs?
I'm looking at doing something like this in the apache config:
RewriteEngine On
RewriteCond %{DOCUMENT_ROOT}/maintenance.mode -f
#RewriteCond %{REMOTE_ADDR} ## check list of exceptions??
RewriteRule !^maintenance/.*$ /maintenance/ [R,L]

Answer: You can have the blacklist/whitelist in a separate file. Have a look at http://httpd.apache.org/docs/2.2/rewrite/access.html#host-deny - it should give you enough to go on to start with.


"Miss to inform" or "fail to inform"

Question: Do you miss to inform someone or fail to inform them? I am seeing miss appear in places but it just seems awkward.
Comment: I don't think it's *miss to inform* but rather *misinform* , which is a verb and means *to give someone false or inaccurate information.*
Answer: "Misinform" is typically used to refer to an instance in which you provide incorrect information.
"Fail to inform" would refer to an instance in which you do not provide information at all.
A quick survey of Google results indicates that all uses of "miss to inform" are the result of what appears to be poor translation, which would be in keeping with my own observations — I've never heard the phrase used by a native speaker or in any context that wasn't garbled Engrish or equivalent.
Comment: I can add to the above by saying that a source for this answer is a lifetime of speaking English. This answer is correct.
Comment: Any source of your answer? please
Answer: When the verb "miss" takes a clausal complement, it is a gerund (form in -ing), not an infinitive.
So missed informing him is possible, though rather less likely than failed to inform him. But *missed to inform him is not something that a native English speaker would say.
The verb miss in this way has an implication that the person who missed it expected or planned for it to happen. So I missed informing him has a strong implication that this was something I specifically intended to do, but something happened to stop me; whereas I failed to inform him doesn't have that implication: I might have intended to, or I might never have intended to (though presumably somebody thought I would do so, or I wouldn't have occasion to say this!).

"Miss to inform" or "fail to inform"


Are there any implementations of smart contracts in Python?

Question: I want to implement some smart contracts and I am strongest in python.
Comment: The other answer give great information, though I think using Serpent and Viper might be more time consuming than learning Solidity. It's not a very hard language to learn and and being strongest in python is not the strongest reason to use Serpent or Vyper instead of Solidity.
Answer: pythereum and pythapp - your question tags - are Python implementations of Ethereum's core library and command line client respectively. They are orthogonal to the language in which smart contracts are written.
So the short answer to your question is: no.
Having said that, have a look at Serpent: https://github.com/ethereum/wiki/wiki/Serpent
Comment: Is it possible to do that though?
Comment: See the other answer from eth. In theory you could write a smart contract in any language you like, but you'd also need to write a compiler.
Answer: Ethereum smart contracts need to compile to EVM (Ethereum Virtual Machine) bytecode.  There are no Python to EVM compilers, and for some of the challenges, see What is the merit of creating new smart contract languages like Solidity instead of using other languages?
The options are to use a Python-like language Serpent or a recent (Nov 2016) experimental language named Viper.
See this for additional information on Viper and Serpent, including their differences.
Comment: What about creating a python to solidity or python to serpent transpiler?
Comment: @nueverest Yes, those are options.  Another option is transpiling to Solidity's [Standalone Assembly](http://solidity.readthedocs.io/en/develop/assembly.html#standalone-assembly).
Answer: There is now - Lamden Tau handles Python smart contracts, although it is as different blockchain than Ethereum