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July 15

Durian Fruit

I have smelt 'Durian' but it is too stinky. What may be the reason behind its stinkiness. — Preceding unsigned comment added by Sahil shrestha (talk • contribs) 02:48, 15 July 2016 (UTC)

See our article - Durian#Flavour and odour - my guess would be the sulfur compounds and the reason for the difference in perception being related to the asparagus urine smell (see asparagusic acid) where some people don't detect / smell the sulfur compounds produced by the metabolites. EdChem (talk) 03:39, 15 July 2016 (UTC)

An important odorant is 1,1-Ethanedithiol. Graeme Bartlett (talk) 03:56, 15 July 2016 (UTC)

Identify this bird

I saw this very large bird sitting on my neighbor's deck yesterday. In Northern California, San Francisco Bay Area. I thought it might be a turkey vulture but the head is whitish rather than red and the neck doesn't really look like a turkey vulture. It's also pretty bulky for a vulture, so I thought it might be a wild turkey, but it doesn't seem to have a wattle, and I've never heard of wild turkeys living in this area. Photos: CodeTalker (talk) 16:13, 15 July 2016 (UTC)

I suspect it is a turkey - though a juvenile so the wattle isn't yet fully developed. The distribution map shows that there is a population in northern California and Oregon. Wymspen (talk) 19:21, 15 July 2016 (UTC)

Yes, that is clearly a turkey. Matt Deres (talk) 20:14, 15 July 2016 (UTC)

I agree that it looks more like a turkey, but just for completeness, take a look at the turkey vulture. Doesn't look quite like your bird. StuRat (talk) 21:26, 15 July 2016 (UTC)

I know someone in Albany who often reports seeing turkeys; I'm not sure whether they're running wild or belong to some neighbor. —Tamfang (talk) 09:34, 16 July 2016 (UTC)

Or maybe they are just watching election news. :-) StuRat (talk) 17:49, 16 July 2016 (UTC)

• Yup, t'is a turkey all right, you can't but not see Meleagris gallopavo back in my hometown (the northernmost in South Jersey), whether at dawn or dusk.

I could quit my job and lead tours, except everybody's at McDonalds or getting Pop-Eye's take-out that time of day.

These beasties've made such a comeback since the suburbs have replaced hunting the critters fer food it's downright dangerous.

Deer, raccoons, opossums, woodchucks have all literally exploded. (Mostly July 4th.) We even had that rabbit plague a few years back. They've crashed, but they're back too.

And here in NYC that have the rat clubs. Next it'll be flying lizards and freezing gorillers. Much of the US has greatly rewilded in the last century, and the commensals are doing just fine. Next it will be panders. In fact, my dad installed a cardinal-trap, although he's having a hard time finding willing suet. μηδείς (talk) 04:24, 18 July 2016 (UTC)

Let's hope that the gorillers and panders don't meet up with any iguaners. Sorry, I couldn't think of a llamer joke. Akld guy (talk) 21:36, 18 July 2016 (UTC)

Definitely Not a Turkey vulture. Our own article has this photo. Note the hook at the tip of the beak which has presumably evolved to help the bird tear at meat. The turkey is largely a herbivore (but does sometimes eat frogs, lizards or rodents) and has a very differently shaped beak, very similar to that in the OP's photos. DrChrissy 22:02, 18 July 2016 (UTC)

Computer UV LEDs effects on the body and electronic components

I am playing around with a custom liquid cooling system, and plan to use UV reactive tubing. To have the glowing effect on the tubing, UV LEDs are required (for example). I am hestitate to order because of the questionable effects of UV on the body (skin & eye) and on the computer components. I don't have the exact model of the UV LED (maybe something like this), and don't think the manufacturer will list the specifications either. But I would like to have some basic guideline and advices, thanks.

Additional information: I will be using a case with full temper glass side panel, which provides no place to hide the UV LEDs. -- Livy (talk) 19:27, 15 July 2016 (UTC)

The effect of UV LEDs on skin is the same as that of sun light - tanning (unless you use UV-C LEDs). So, nothing to fear. Ruslik_Zero 19:49, 15 July 2016 (UTC)

Not really, since it's very well-established that UV exposure increases your risk of skin cancer. Tanning is a response to skin damage from UV light. I would avoid any unnecessary exposure to UV light sources. You'll survive without glowy tubes. (And incidentally, I think liquid cooling for computers is a waste of money, at least for personal computers, but hey, it's your money, not mine.) --71.110.8.102 (talk) 20:02, 15 July 2016 (UTC)

I know. It is mostly for aesthetic purpose. -- Livy (talk) 20:47, 15 July 2016 (UTC)

(edit conflict) Tanning... and cancer. But of course, the question is how much radiation will be received, and eyes are more fragile than skin anyways.

@Livy: Misplaced Pages does not give medical advice, so you will not get an answer to the question "is it safe to do X". You can start at Mercury-vapor_lamp#Ultraviolet_hazards, though I tend to think that UV LEDs will be less dangerous than spectral lamps. I think a PC-building forum would be the place to go for more specific info about how to build your system (where to put which part); if the UV source goes inside the case so that you only see the luminescence, I would assume it will be OK from a health perspective. Tigraan 20:10, 15 July 2016 (UTC)

I am not asking where to put the UV LEDs. I know it is best to keep them hidden. In this case, I am wondering if the tempered glass reduces the effect of UV by any chance. I know what to buy for my PC system and where to put them. It is not really a medical matter either I think -- I am not searching for a solution to my illness. I just want to know the short and long term effects of consumer UV LEDs on the body and on the electronic components (if any). -- Livy (talk) 20:47, 15 July 2016 (UTC)

Tempered glass will not significantly reduce UV flux at the wavelengths that consumer-grade UV LEDs typically operate (350-400 nm). Dragons flight (talk) 20:57, 15 July 2016 (UTC)

Also, you can determine this by experiment. Does a length of UV reactive tubing still glow when the glass is between it and the UV source? If yes, then the glass does not block UV. It isn't a perfect test, but it is better than nothing and easy to do. BTW, while we cannot give medical advice, we can certainly give engineering advice about whether long-term exposure to UV LEDS damage computer motherboards. I am guessing no but I would like to see a source. --Guy Macon (talk) 06:24, 16 July 2016 (UTC)

I am not sure that UV LEDs in in the 350-400 nm range would cause any significant risk of skin cancer, which is mainly related to the shorter UV-C and UV-B ranges. However I agree that they are not eye-safe. Ruslik_Zero 20:22, 16 July 2016 (UTC)

You might consider hooking the UV LEDs to a separate switch and then only turn them on for brief periods when you are showing off. Many fancy cases have switches built in for controlling LEDs. Dragons flight (talk) 06:43, 16 July 2016 (UTC)

July 16

Ionisation energies of actinides and lanthanides

I would have expected that the actinides would have lower ionisation energies than the lanthanides, since the 5f electrons would be further away from the nucleus than the 4f electrons of the lanthanides, and wouold be screened by more electrons. Furthermore, since only the first two lanthanides (Ce and Pr) can reach the oxidation state corresponding to the loss of all valence electrons (and Pr needs noble-gas matrix isolation conditions to do so), but the first five actinides can do it (Th, Pa, U, Np, and Pu, although only transiently for Pu), it would seem that the outer electrons of the early actinides are being held less firmly than those of the early lanthanides. Yet the list molar ionization energies of the elements on Misplaced Pages gives the opposite trend: Th has first ionisation energy 587 kJ/mol, while Ce has 534.4 kJ/mol, for example. Why is this so? Double sharp (talk) 14:16, 16 July 2016 (UTC)

In general, actinide behavior does not obey the periodic law as well as lower atomic number elements. That is, the trends predictable by an elements position on the periodic table break down by the time one gets to the actinides. Part of this is connected to the unpredictability of the electron configuration of actinides. Thorium for example has 6d2 7s2 while Protactinium is 5f2 6d1 7s2 and so on. --Jayron32 02:27, 17 July 2016 (UTC)

Could you go into a little more detail behind the causes for this? Maybe it's easier for a specific case, so for example, in particular, why is removing a 6s electron from a cerium atom easier than removing a 7s electron from a thorium atom? (And why is it that the pairs La/Ac, Gd/Cm, and Lu/Lr are exceptions, and behave the way I would naïvely think they ought to, with lanthanum having a higher ionisation energy than actinium?) Double sharp (talk) 12:17, 18 July 2016 (UTC)

Adolescent

1. Define, , , adolescent age group.
2. What’s the correct word to use from “” stated above?

Apostle (talk) 18:38, 16 July 2016 (UTC)

Read Adolescence. ←Baseball Bugs carrots→ 19:29, 16 July 2016 (UTC)

"Pubescent" is often used in that context. The ages vary quite a bit, depending on sex, ethnicity, diet, and weight.StuRat (talk) 21:20, 16 July 2016 (UTC)

I Know, this is where the confusion is, I don't know whether I should use age numbers or the words specified in this post for my book. Any suggestion? -- Apostle (talk) 06:38, 17 July 2016 (UTC)

Choose whichever you prefer, define them clearly, and be consistent. Wymspen (talk) 10:58, 17 July 2016 (UTC)

Thats the problem, I have ESL issue. -- Apostle (talk) 04:58, 18 July 2016 (UTC)

What is it about the term "adolescence" that you do not understand? ←Baseball Bugs carrots→ 12:19, 18 July 2016 (UTC)

• Our crystal balls don't tell us how you want to use such a word. —Tamfang (talk) 20:56, 17 July 2016 (UTC)

Lol. -- Apostle (talk) 04:58, 18 July 2016 (UTC)

Baseball Bugs: I want to use the word adolescence/adolescent rather than "At the age of _____,". If you can specify the age period (from to to) than I'll know the period.

So what do guys say?

Apostle (talk) 06:06, 19 July 2016 (UTC)

Creation and evolution in Russia

Of the approximately 145,000,000 residents of Russia, (a) how many believe that life was created by a supernatural intelligence, and (b) how many believe that life originated by spontaneous biogenesis and developed by macroevolution? (Also, how are those statistics distributed: by age, by sex, by subnational entity, by education, by occupation, and by religious status?)—Wavelength (talk) 23:13, 16 July 2016 (UTC)

Not as detailed as what you requested, but relevant: Creationism in Russia? Shock Brigade Harvester Boris (talk) 23:40, 16 July 2016 (UTC)

July 17

Physics curiosity

Suppose, I can move at the speed of sound. When a speaker speaks then simultaneously I also start to move at the direction of sound at the speed of the sound then what sound will I hear if the speaker has said "Hello"? and if I myself speak any word then will I be able to hear my own voice incase i move faster than sound? — Preceding unsigned comment added by Sahil shrestha (talk • contribs) 02:15, 17 July 2016 (UTC)

You won't hear the speaker, since you and the speaker's sound waves will be moving at the same speed. The sound waves need to hit your eardrums for you to hear them. Assuming you're inside a craft, you will be able to hear yourself just fine. There are myriad videos of people speaking just fine inside aircraft traveling at supersonic speeds. The thing to remember here is that speeds in general are relative to a frame of reference. If you run around inside an aircraft in flight, we don't consider you to be running at 100+ kilometers per hour, because we measure your speed relative to the body of the aircraft. The air inside the craft is being carried along with you, and it's at rest relative to you. (If we posit that you have superpowers and aren't flying in a craft, you might have trouble speaking due to the air barreling down your airway, though you'd need some secondary superpowers anyway to be able to breathe and not have your lungs explode, or to not require breathing.) --71.110.8.102 (talk) 06:23, 17 July 2016 (UTC)

Note that I interpreted the questioner's statement as "you move in the same direction as the speaker's sound waves", in other words, away from the speaker. Re-reading it, it seems unclear. --71.110.8.102 (talk) 06:28, 17 July 2016 (UTC)

You might be interested in the doppler effect. As you are moving away from the speaker, the apparent frequency of the sound he makes will get lower the faster you move away from him. When you reach the speed of sound, all aspects of the speaker's voice drop to a frequency of 0, and you can no longer hear anything at all from him. As for your own voice, well, that depends on what factors you want to include. As 71.110 mentioned, your exposed body were simply flung through the air at the speed of sound, you would be dead. If we ignore that, you'll just hear your voice normally through the vibrations in your skull, though that may be drowned out by the rushing air. If we ignore all of these factors, that depends on where the sound is generated relative to your ears. Sound moves at the speed of sound relative to the air itself, not the speed of the sound-maker. A super sonic jet, for instance, does not project any sound ahead of itself. It does project sound in the forward direction, but at the speed of sound relative to air, which it is outrunning. So if your sound is being made ahead of your ears, you will hear it doppler shifted to a very high frequency. If your sound is being made behind your ears, you will not hear a thing. Again, ignoring all these other little factors. Someguy1221 (talk) 06:35, 17 July 2016 (UTC)

@Sahil, the Good News is that you can move at the SoS (Speed of Sound) which is 343.2 m/s. Just stand at the Equator where you and everything around you are moving eastwards at 465.1 m/s. That's faster than you want, but knowing that the surface rotational speed is proportional to the cosine of the latitude you can reposition yourself north (or south) to latitude 44.45° (or minus 44.45°) to adjust your speed to the SoS. At least you could have done, had not astronomers discarded the geocentric in favour of the heliocentric system in which everything at the equator is moving at about 79000 m/s due to Earth's orbit around the Sun. So the Bad News is that makes it very difficult, short of a major investment in rocketry, to move as you suppose. See Orbital speed, Geocentric model and Heliocentrism. AllBestFaith (talk) 17:34, 17 July 2016 (UTC)

That doesn't really figure into it, as per the frame-of-reference cited earlier. If you are standing next to someone, your speed relative to the center of the earth, the solar system, the galaxy, etc. don't matter. Compared to each other, you're standing still. ←Baseball Bugs carrots→ 17:57, 17 July 2016 (UTC)

Why is the UK and US building different trident-armed submarines?

America is building the Ohio Replacement Submarine while Britain is building the Successor-class submarine. Both will cost around 7 billion each and they'll start to enter service in 2028/2031. Can anybody tell me the difference between them in terms of engineering/specs? Also, while not a science question, does anybody know why both countries aren't building the same? It'd be cheaper that way. 2.103.15.147 (talk) 02:30, 17 July 2016 (UTC)

Here is a free report available to the public from the RAND Corporation, a very famous American organization that has had very strong historical ties to the nuclear policy decision-makers in the United States government: The British Nuclear Deterrent After the Cold War (1995). It's a good overview that explains why things are the way things are. There is a lot of politics behind the American/British Trident nuclear missile program, so this report will help give you some background. And here is a 1984 report, British Nuclear Policy-Making.

Directly addressing the "costs" of the submarines: the author Nicolas Witney of the Ministry of Defence eloquently phrases it, in pleasant British English, "...such sums, though by no means trivial, do not weigh heavily when set set against the sunk costs and the importance long ascribed by successive British governments to the strategic deterrent." Or as I say it, in my brasher American idiolect, when we're talking about blowing up the planet, "money" ceases to have any meaningful economic implication.

Here is a well-cited article from the Fall 2003 RAND Review: Excessive Force: Why Russian and U.S. Nuclear Postures Perpetuate Cold War Risks.

Britain's choice to deploy an American-made nuclear weapon on a British-made nuclear submarine is rooted in their government's perceived need for their nation to have independent control of the nuclear arsenal, while satisfying domestic political concerns that preclude them from independently designing a nuclear weapon.

This 2007 book, part of the RAND Monograph series, Sustaining U.S. Nuclear Submarine Design Capabilities, defends the position that it is necessary for a nuclear-weapon-state to design a nuclear submarine fairly frequently to ensure that critical institutional knowledge and skills are preserved, in case that knowledge, skill-set, and engineering infrastructure is ever needed in the future. Surely, the decision-makers in the British government consider the very same issue.

Nimur (talk) 03:41, 17 July 2016 (UTC)

Here's a great resource from Royal United Services Institute - sort of a British counterpart to RAND: Continuous At-Sea Deterrence: Costs and Alternatives. In this report, there is considerable discussion (based on the theory of nuclear deterrence, which is another topic worth reading about). On this topic, it is claimed that Britain cannot cease its continuously-available nuclear deterrence unless both the United States and Russia make significant policy-changes. Ultimately - and this is a sinister conclusion that is very extensively studied - the UK cannot trust the Americans as an ally unless the UK maintains the credible capability to independently annihilate the Americans. Our article on the so-called security dilemma has some references on the topic of uneasy alliances in nuclear strategy theory. If you read extensively on the topic of why we even have nuclear submarines - particularly, with respect to the role nuclear submarines play in the theory of second strike capability, you'll find that this theme recurs very frequently. Nimur (talk) 03:55, 17 July 2016 (UTC)

It should not be a matter for surprise that the British do not trust Donald Trump. In a worst-case scenario it might even be a matter of relief to the US public that Britain has something purporting to be an independent weapon that might deter. Unfortunately, by that time, Trump will know that he has an override. Thincat (talk) 13:48, 17 July 2016 (UTC)

The difference is that one is a pointless porkbarrel for local jobs in the US, the other is an even more pointless porkbarrel for jobs in the UK. In a part of the UK which might not even be in the UK for much longer. Andy Dingley (talk) 14:38, 17 July 2016 (UTC)

Actually very little pork for Scotland, but a lot for Barrow-in-Furness. Assuming you're not envisaging an independent Cumbria. Henry 16:48, 17 July 2016 (UTC)

The UK ones are built in England, but based in Scotland - so that does create jobs in both areas. Wymspen (talk) 17:27, 17 July 2016 (UTC)

conical pendulum -Referencedesk Archives/Science2016May31

If we disregard the force to start and maintain constant movement of a conical pendulum, are there any practical(scientific/commercial) purposes to which the force generated /the movement created can be utilised. Eg electrical generation in remote areas. Assume a small pendulum length of say 600mm.139.216.164.174 (talk) 21:03, 17 July 2016 (UTC)

Any attempt to extract work from the pendulum will quickly cause it to stop swinging. As you were told back in May, there is no such thing as a perpetual motion machine, and you can't get energy for free. Rojomoke (talk) 21:32, 17 July 2016 (UTC)

Dogs protecting humans

There are many stories about dogs protecting humans, sometimes sacrificing themselves. This is very unusual; few animals will die for non-relatives. How much has this behavior been studied? 69.22.242.15 (talk) 22:03, 17 July 2016 (UTC)

Well, while the origin of the domestic dog is complex, they are definitely related to wolves, and some of those have an alpha pair that mate and produce offspring, while the rest of the pack does not breed. The rest of the pack are related to the alpha pair, though, so the best chance to pass on their genes may be to protect the alpha pair, even if they themselves die. Since humans often take on the role of "alphas" in their relationship with dogs, this instinct may continue, even if it no longer is biologically "logical". StuRat (talk) 22:34, 17 July 2016 (UTC)

Even with children: In separate rattlesnake attacks, dog saves child and child saves dog. μηδείς (talk) 23:19, 17 July 2016 (UTC)

Cats protecting humans?

Inspired by the thread above. Why would a cat protect a human child from a dog attack? I thought that cats generally didn't care about anyone other than themselves?

Vid:

https://www.youtube.com/watch?v=aBW5dfRoG7Q

--146.90.107.28 (talk) 23:28, 17 July 2016 (UTC)

Cats care about their kittens and that mechanism is easily displaced (for lack of a better term) toward human family. Most interactions between humans and domestic cats can be explained in terms of parent-child relationships. Ian.thomson (talk) 23:31, 17 July 2016 (UTC)

Yes, I've heard that the behavior of bringing live (but wounded) mice/birds/frogs to humans to finish off can be a manifestation of that. --146.90.107.28 (talk) 23:42, 17 July 2016 (UTC)

I'm a little dubious about the video, which is shot from two different viewpoints which just happen to be perfect to capture all the action. Staged? {The poster formerly known as 87.81.230.195} 2.123.26.60 (talk) 00:51, 18 July 2016 (UTC)

The stationary, elevated cameras with timestamps feel like security cameras to me. It is plausible that one would arrange such cameras to cover a wide range of angles, though of course having multiple security cameras would be quite unusual for a private home. Dragons flight (talk) 09:27, 18 July 2016 (UTC)

I don't know if it's really that uncommon for homes to have multiple cameras, particularly not in the modern digital and wireless world, as it's easy even for a fisheye lens camera (which this isn't anyway) to miss likely points of entry for even an unaware thief. Cameras are generally mostly as a deterrence, still even for home they are use as evidence and for monitoring. Nil Einne (talk) 19:05, 18 July 2016 (UTC)

We're interpreting the video as the cat saving the child. It might be doing so, but it might also simply be protecting its territory from an invader. Back when I had an outdoor cat, I observed it defending its turf from even large dogs when the humans were in no danger whatever. By that same token, our presence also seemed to galvanize the cat, who perhaps assumed that we would take up the fight against the foreign aggressors alongside it. As for this particular video, I don't see anything particularly suspect about it; they're fairly clearly security camera shots. Matt Deres (talk) 16:12, 18 July 2016 (UTC)

I agree totally with Matt. Modern ethologists have worked diligently to make their subject a "hard" science. Interpretations such as "the cat saved my son" are simply unacceptable without further investigation. Possibly, it was a highly defensive cat and it attacked this dog every time it encroached on the cat's territory (not notable), but on this day there was a child involved (notable). Possibly it was a female cat with kittens and she was protecting her offspring. Two of the main principles of modern ethology are Morgan's Canon and Occam's razor - I urge editors interested in animal behaviour to read these. Whilst anthropomorphism or anthropocentrism are less frowned upon these days, it should still be used in moderation. DrChrissy 21:51, 18 July 2016 (UTC)

SAS snipers training to shoot the engine blocks of speeding trucks?

Just been talking to my father about this story in the paper today concerning SAS snipers training to stop a potential terrorist truck attack in the UK, similar to the Nice atrocity.

What manner of weapon/ammunition would they use for this, do you think? The Barret M82 firing tungsten-tipped rounds? I know there's a lot of myths about 'shooting through the engine block' (I know that a .44 magnum pistol can't actually do this, despite the pop culture thing). --146.90.107.28 (talk) 23:40, 17 July 2016 (UTC)

I have not been able to find any military sources detailing what they expect their .50 armor piercing rounds to actual do, and what soldiers are trained to do. But you can easily find a ton of videos on youtube of people shooting engine blocks with .50 rounds of various types to see what happens. One video does show a running truck engine stop after being hit by a .50 armor piercing round . Someguy1221 (talk) 01:05, 18 July 2016 (UTC)

It's worth noting that the Daily Hate story is, for the most part, confected bullshit, even down to their reuse of a 2013 photo of a sniper completely unrelated to the SAS. --Tagishsimon (talk) 01:11, 18 July 2016 (UTC)

And WHICH parts of the story, exactly, ARE fabricated??? 2601:646:8E01:7E0B:258A:F94:7EFA:6739 (talk) 02:01, 18 July 2016 (UTC)

As poor as The Daily Mail normally is, I would be reluctant to blame them for the general tone of the story. The explicitly quote the (IMO) better Sunday Times as the originators of the story including quoting people quoted in The Sunday Times. And while I can't read the whole story, the gist of the Daily Mail story appears to be supported by the part I did read on the Sunday Times. Actually if you read the Daily Mail story carefully, other than the second paragraph, there seems to be almost no original reporting by the Daily Mail of particular relevance. Any relevant parts seem to come from the Sunday Times and the other stuff is just fluff about the attack in Nice that doesn't relate to the claims. Not that this explains any misleading imagery, wording etc that does originate in the Daily Mail; simply that whatever alleged bullshit about what the SAS is or isn't doing and why would seem to come from the Sunday Times. It would undoubtedly be better to read the original story (except maybe not easy if you don't have a subscription), not the Daily Mail's reporting of it if you want more reliable info. Nil Einne (talk) 10:03, 18 July 2016 (UTC)

If you have that kind of firepower, I should think killing the driver would be the more effective way to stop a truck. StuRat (talk) 01:15, 18 July 2016 (UTC)

I wasn't aware that SAS had branched out into weaponry. ←Baseball Bugs carrots→ 01:44, 18 July 2016 (UTC)

great joke, my sides! lol! 90.63.167.63 (talk) 02:19, 18 July 2016 (UTC)

You'll get over it. The OP assumes everyone knows what he means by "SAS", and the SAS Institute is the only one I know anything about. ←Baseball Bugs carrots→ 12:17, 18 July 2016 (UTC)

If only there was somewhere on the internet you could type "SAS" into to educate yourself before spouting meaningless and unhelpful nonsense. Like, some kind of big online encyclopedia. Nah, that's just silly. 90.63.167.63 (talk) 18:08, 18 July 2016 (UTC) This template must be substituted.

Americans are routinely berated for assuming that other editors know what they're talking about, even when it's something that can easily be looked up. If that's the standard, I don't see why Britons should get a pass. But yes, it would be better if everyone would accept that sometimes they're not going to know the background to every question, and be willing to spend ten seconds Googling before complaining about it. --Trovatore (talk) 18:27, 18 July 2016 (UTC)

I always assumed that SAS meant their "Special Armored Sheep" division. StuRat (talk) 13:29, 18 July 2016 (UTC)

The photo in the Mail link shows what looks like a AW50F snipers rifle. The kinetic energy is far higher than that from a 45 Magnum hand gun (upwards of 10,000 foot-pounds). A saboted light armor penetrator discharged from that rifle and hitting an engine block will instantly invalidated that trucks 100,000 mile warranty.--Aspro (talk) 13:09, 18 July 2016 (UTC)

Post script. Looking up the rifle (not literally but metaphorically on google) just found this: SAS stops Islamic State convoy with just TWO bullets as British Army troops return to Iraq Likewise, I didn't know SAS had branched out in to software – strange world.--Aspro (talk) 13:21, 18 July 2016 (UTC)

I should point out that the Daily Express's reputation isn't significantly higher than that of the Mail. Tevildo (talk) 19:28, 18 July 2016 (UTC)

Be aware that propaganda does not necessitate truth, merely stories. --Dweller (talk) Become old fashioned! 13:30, 18 July 2016 (UTC)

Perhaps the OP would like to read about anti-materiel rifles? However, even with the heightened state of security in France and in other places, most soldiers deployed for urban defense will not be carrying around such a weapon-system; in France, soldiers typically carry the distinctively-shaped FAMAS service rifle. This rifle fires a round that would probably not penetrate a truck's engine block. In the specific case of the recent truck attack, the responding agency was the Gendarmerie, and the first rounds fired were from handguns; national police and national Army soldiers arrived from nearby positions very promptly afterward. Law enforcement in France is complicated, and operations sometimes involve actual deployment of the army - especially in the present state-of-emergency.

In the United States, I do not believe any law enforcement agencies deploy an anti-materiel rifle like the Barrett M82. There has been much concern recently about militarization of the police, but even amidst these concerns, there are some weapons that civil law enforcement simply does not bring to the proverbial gunfight. I am not sure what standards exist in the UK; but they tend to use fewer firearms than American or French police. I doubt anti-materiel rifles are in the standard civil police arsenal in the UK.

Regarding training: I'm pretty certain that the standard doctrine in American counter-truck operations is to train soldiers for aimed shots and to aim for the driver - not to aim for the engine block. A statistical review of Army combat in Viet Nam found that single, well-placed, aimed shots were more effective than un-aimed automatic fire, and therefore "aim" is a heavily-emphasized primary element of modern training. A lot of emphasis is preventative: use of concrete blockades, for example, is a great way to keep the truck far away from the soft targets. The American military has a lot of doctrine developed in response to trucks, because we have a bad history, e.g., the 1983 Beirut barracks bombings (in which a truck crashed through a gate); and the Oklahoma City Bombing (in which a stationary truck-bomb was allowed to get closer to the building than desired); and to the perennial threat of the VBIED encountered during the last decades of combat. From FM 3-21, Urban Operations, there is much discussion about the threat from vehicles including trucks. From FM 3-24, Counter-Insurgency Operations - there's no mention of shooting engine blocks. This probably means it is an ineffective tactic - especially if your defender doesn't employ a weapon system that is specifically engineered to destroy the vehicle.

All this theory still won't harden every soft target, but it might help reduce fatalities if more people - civil and military defenders, as well as all the members of the crowd - learn how best to react to a terrible occurrence.

Nimur (talk) 14:55, 18 July 2016 (UTC)

Well I hope such weapons aren't for sale to 16 year olds in the US. Even if they do need them to protect themselves like the gun lobby keep saying. Anyway isn't the most effective defense against such attacks to simply park a large lorry at right angles across the approach roads to stop any traffic when there is a big celebration? Dmcq (talk) 17:22, 18 July 2016 (UTC)

They're for sale to 18 year olds willing to spend thousands of dollars on things with no practical purpose. Well the semiautomatic and single-shot ones. Come to think of it large trucks blocking the exits might be a crowd "crush" hazard, but no vehicles blocking the entrances is also a safety hazard so who knows which is better. A protected area much larger than the crowd would be better, but close many streets to traffic. The checkpoints could let vehicles in after vetting all, possibly at the risk of not checking hard enough and letting a terrorist through. Sagittarian Milky Way (talk) 22:14, 18 July 2016 (UTC)

They wouldn't block the street for people! People are smaller than lorries. You just need a passage a few feet wide at each end. Such lorries could also be used to carry equipment for any extra security that may be required like checkpoints. Dmcq (talk) 22:29, 18 July 2016 (UTC)

"I do not believe any law enforcement agencies deploy an anti-materiel rifle". If only. The NYPD has a small collection of anti-material rifles which they have proudly shown off and discussed. Saying things like "we can stop a truck by shooting its engine" or "bring down a small plane", I think they use the guns more for public relations value than any actual utility. Dragons flight (talk) 22:49, 18 July 2016 (UTC)

See . A couple of full metal jacket 50 caliber rounds into an engine block, then (Starting at 2:10) an armor piercing incendiary round. On of the standard bullets cracked the block and badly bent a piston rod, but the armor piercing bullet went through multiple layers of metal, filling one of the cylinders with chunks of cast iron. --Guy Macon (talk) 22:57, 18 July 2016 (UTC)

July 18

Roughly how many people may have been alive during the last glacial maximum?

Just like the headline, I'd like to know if there is any estimate as to how many people (in the world) may have been alive during the last ice age. My guess is about 500,000, but I could be way off. I would accept an estimate for any point of the last ice age. I'm not picky! Thanks! Lighthead 00:47, 18 July 2016 (UTC)

It has been recently estimated that the human population reached a minimum size of 130,000 individuals during the LGM, but this is highly speculative . The field of paleodemography has attempted to produce estimates based on genetic and archaeological data, but this gets more speculative going further back (with people often doubting any estimates prior to 10,000 BCE), and the genetics is limited in that it can only produce estimates of the number of people at a given time who have currently living ancestors (though you can then estimate based on simulations how many people there were total). Someguy1221 (talk) 00:57, 18 July 2016 (UTC)

Note this estimate is only for the population of Europe. World_population#Past_population gives a global population estimate of 4 million at 10,000 BCE which was around the time that temperatures reached near-current values after the last glacial maximum. The same article gives an estimate of <15,000 at 70,000 BCE, when ice sheets had reached near maximum following the onset of glaciation. As Someguy1221 points out all of these estimates need to be taken with a few grains of salt, or a whole shaker-full.

There's a nice figure here comparing δO (an indication of glacial ice volume) to prehistoric human activity. Shock Brigade Harvester Boris (talk) 02:48, 18 July 2016 (UTC)

Paleodemography is the go-to article. Technically, of course, we are currently still in an interglacial period of the Quaternary glaciation, but I guess you probably mean the Last glacial period, which has different names in different localities and ended about 12,000 years ago. {The poster formerly known as 87.81.230.195} 2.123.26.60 (talk) 01:02, 18 July 2016 (UTC)

Thanks for all the responses! Lighthead 02:58, 18 July 2016 (UTC)

Websites extracting phone numbers

Is it possible for a website to find out the phone number of a smart phone that is used to visit the site ? - WikiCheng | Talk 08:10, 18 July 2016 (UTC)

When accessed via a web browser, the answer should ordinarily be no. A malicious or hacked website that tricks you into downloading a computer virus to your phone might be able to do that, but I've never heard of an example of that. If you are using an specialized app or game on your phone to access some web service, then they may or may not have access to your phone number depending on what permissions you have given the app. Dragons flight (talk) 09:22, 18 July 2016 (UTC)

As Plugin or AddOn to the webbrowser, some VoIP and internet telephone software highlight possible phone numbers to start a call. A prankster who thinks evil doing due AddOns of some browsers come in source code as well. --Hans Haase (有问题吗) 09:47, 18 July 2016 (UTC)

Searching For Easiest Way

Is there any easy way to study completely about the geological timeline of Earth ?(ie. from Azoic to Phanerozoic Eon with their divisions) — Preceding unsigned comment added by Achyut Prashad Paudel (talk • contribs) 13:55, 18 July 2016 (UTC)

You could start with Geologic time scale. ←Baseball Bugs carrots→ 14:19, 18 July 2016 (UTC)

Simple Misplaced Pages has an article about Historical geology. AllBestFaith (talk) 19:32, 18 July 2016 (UTC)

I recall that there was a mnemonic device for geologic time periods, but (of course) don't remember what it was. Google search finds several sites such as Order of geological time periods on 'Mnemonic Devices Memory Tools' site. --However, memorizing is not the same as studying, or - more importantly - learning. --2606:A000:4C0C:E200:8558:6C31:688B:8595 (talk) 23:32, 18 July 2016 (UTC)

About Latitudes

The climatic condition of place is determined by latitudes but why it can't in case of Country of Nepal? — Preceding unsigned comment added by Achyut Prashad Paudel (talk • contribs) 13:59, 18 July 2016 (UTC)

Latitude is only one factor. Much of Nepal is in the mountains, and altitude has a significant impact on climate. ←Baseball Bugs carrots→ 14:18, 18 July 2016 (UTC)

Altitude is important - so is distance from the coast, and where you are in relation to the main weather patterns. Nepal is mostly high altitude, well inland, and in the direct track of the Indian Ocean monsoons. Wymspen (talk) 15:32, 18 July 2016 (UTC)

Agreed. This is why meteorologists and climatologists must be given a wide latitude. StuRat (talk) 20:07, 18 July 2016 (UTC)

July 19

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