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January 8

Euginic is base from correct evoltion science?

If no, can explain why is wrong science? If yes, what evoltion scientist think about discrimation base from euginic? Sorry for bad English. --Curious Cat On Her Last Life (talk) 08:50, 8 January 2017 (UTC)

No, because it entirely overlooks the effects of genetic defects arising from spontaneous mutation -- effects which are amplified by inbreeding. (Also the reduced resistance of an inbred population to infectious disease, kind of like what we're seeing right now with bananas.) To be honest, though, these effects were not fully understood when eugenics started out -- so it's more precise to say that eugenics are not so much "flat-out wrong" science as they are outdated science. 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 09:36, 8 January 2017 (UTC)

We have an article on eugenics. Historically, the problems with eugenics were that A) People assigned to genetics traits that are not genetic in origin, such as criminality or poverty, and B) People who have promoted eugenics are frequently mind-bogglingly racist or otherwise so bigoted their decisions have nothing to do with actual science. I'm sure there are scientists (of evolution and otherwise) who would support the elimination of clearly deleterious genes through either genetic engineering, selective abortion, selective fertilization, or voluntary non-reproduction. Genes for diseases like tay sachs or Huntington's, which are not believed to confer any advantage to the carrier. But given that research ethics is such an integral part of modern science education, I doubt many would support involuntary means of getting rid of these genes. You can read about some of this at History of eugenics#Modern eugenics, genetic engineering, and ethical re-evaluation. Now, this is very different from the original idea of Eugenics. Back in the early 20th century, there was some Nietzshean fantasy of creating more perfect humans through eugenics, rather than simply eliminating a handful of rare deleterious mutations. And as I said before, back when these ideas were young, this lead to totally unscientific things like the Holocaust, or limited American attempts to get rid of poverty through forced sterilization, which suspiciously looked like attempts to get rid of black people (see: Eugenics in the United States). Someguy1221 (talk) 09:29, 8 January 2017 (UTC)

Well, how do we actually know that there is no genetic component whatsoever to criminality??? 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 09:36, 8 January 2017 (UTC)

We don't know even now. The problem is, that didn't stop people from trying to get rid of it. Someguy1221 (talk) 09:47, 8 January 2017 (UTC)

We don't. But we know that environmental factors are more significant hence the U.S. violent crime rate is 5 times higher than other developed nations. TFD (talk) 11:08, 8 January 2017 (UTC)

Additionally, "crime" refers to a whole host of activities, the only completely unifying factor being that the authorities have forbidden them and set specific types of punishment for those who commit them. I think its extremely unlikely that murder, trespass (which isn't a crime where I live, but is in some countries), libel, and watching videos in places the copyright notice says you shouldn't could all have the same genetic cause. (Unless it is simply a genetic propensity to not always obey rules). Besides, even if there was a genetic propensity to any of these activities, it would probably be linked to things that you wouldn't want to breed out of the population. Iapetus (talk) 14:11, 9 January 2017 (UTC)

^{[Citation Needed]}. Our article on List of countries by intentional homicide rate says that you are wrong. It is higher than most, but not five times higher. According to our article on Sex differences in crime, men account for 80.4 percent of persons arrested for violent crime, so we know that genetics plays a very large role. --Guy Macon (talk) 15:10, 8 January 2017 (UTC)

Correlation does not imply causation. --Stephan Schulz (talk) 21:41, 8 January 2017 (UTC)

That is by far the worst application of the "correlation does not imply causation" argument I have ever seen. Do you think that perhaps committing violent crimes reaches back into the past and causes you to be born male? Or perhaps some third factor causes you to be born male and then 20 years later causes you to commit violent crimes? --Guy Macon (talk) 01:50, 9 January 2017 (UTC)

Neither. But I believe that it is well possible that a third factor (our historically evolved society with its gender-stereotyped roles and education) causes males to commit more violent crime, without this necessarily having anything to do with XY vs XX chromosomes. --Stephan Schulz (talk) 02:02, 9 January 2017 (UTC)

Eugenics in all its misanthropic interpretations depends on belief that human character determinism by the genetics of sexual reproduction should be directed by intervention. However when Androcide i.e. systematic male Gendercide occurs, as in July 1995 in the Srebrenica massacre, the misandronist perpetrators are disputing some Casus belli but their act carries no eugenic rationale; their aim is to vanquish the victim group, not to change it genetically. I take this opportunity to commend the above reply by Someguy1221 for his well-thought reponse that concisely gives both historical and ethical perspectives to the OP's questions. Blooteuth (talk) 15:34, 9 January 2017 (UTC)

Well, cultural factors is probably the explanation, but you might argue physiological characteristics (e.g., testosterone makes you prone to confrontation). I guess you could do some comparison with the ratio of male/female propensity to violence in (say) Sweden (where traditional gender roles have almost disappeared) vs. Spain (ok, that choice comes from a stereotype, but still). Tigraan^{Click here to contact me} 16:05, 9 January 2017 (UTC)

Comparing countries with reduced gender roles vs where they are still more closely ingrained may be a useful exercise but I think it's quite qustionable to claim they have "almost disappeared". Sure they may be significantly less than in many other countries but see e.g. [1]. Consider also that it's only recently that some toy stores have tried to avoid presenting toys as being for girls or for boys [2] [3], way too recent to be relevant to the crime rate. Likewise these sort of things [4] are still an oddity. This may seem a minor thing, but on the other hand, it may also be an indication of how early gender roles are part of the social fabric.

And I've chosen my words carefully here, whether you believe there is a very strong genetic component to some of these differences so they aren't likely to disappear, or it's mostly cultural/learnt but such a fundamental part that it's very hard to remove especially in an internationalised world is beside the point namely that for whatever reason these are still there even in places like Sweden. As mentioned, this doesn't preclude some analysis from the differences but still care needs to be taken into reading too much into the results considering that we know such roles still exist to some extent. Especially since violent criminals tend to be outliers, even more so in a place like Sweden.

And once you start to look at the details, there are obvious complications. Switzerland was mentioned below, an obvious thought is that as as established below, there is a difference between conscription etc between males and females. (Even considering the average physiological differences which I think many would accept are significantly of genetic origin, is the lowest standard needed for males higher than the highest standard some females can achieve? Even if this is the case, males who can't achieve the standard often aren't exempted but made to do something else.) And Switzerland is also the place where one canton didn't allow women to vote on certain issues until 1991. Yet despite that, in many ways the situation for women was likely generally perceived as better than, giving a random example, in Pakistan where women have been able to vote since 1947. But how do you decide what cultural differences in the roles and rights of men and women could be affecting violent crime rates?

Nil Einne (talk) 05:05, 10 January 2017 (UTC)

User:The Four Deuces may have been thinking of gun-related homicides: "According to United Nations data, a person is 4.5 times more likely to die from gun violence in the United States than Italy [the next highest G8 nation]. [5] Alansplodge (talk) 20:28, 8 January 2017 (UTC)

Guy Macon, it is true that the U.S. homicide rate declined from 5 to 3.9, while some developed countries have seen an increase. So the list shows Canada at 1.5, France at 1.2, UK, Germany and NZ at 0.9, Switzerland at 0.5 ans Japan at 0.3. 5X is historically accurate and usually quoted. But lets not miss the issue: the differences can be primarily explained by environment rather than genetics. The Swiss, who are mostly French and German, have a 50% lower homicide rate than France or Germany. Alansplodge, gun-related homicides are only one of the factors in making U.S. violent crime rates higher. TFD (talk) 22:29, 8 January 2017 (UTC)

That would be the same Swiss that by law require every home to contain a loaded machine gun, right? Yet somehow they have a lower rate of gun-related homicide that genetically-identical neighbors. So that argues environment/culture. On the other hand, of the homicides and other violent crimes committed in Switzerland, the vast majority are committed by males, just as is the case in all other nations. So that argues genetics. The thing is, there doesn't appear to be any genetic difference in violence between races or ethnic groups. Those differences are primarily cultural. --Guy Macon (talk) 02:00, 9 January 2017 (UTC)

Contrary to NRA propaganda, Switzerland very much does not require every home to contain a loaded machine gun. It requires reserve soldiers in a certain age range to have their service gun (which is usually an assault rifle, which is not, by most definitions, a machine gun) stored securely at home. In particular, it is stored unloaded, and the very limited ammunition supply is stored separately in a sealed (as in tamper-proof seal) container. --Stephan Schulz (talk) 02:09, 9 January 2017 (UTC)

You are somewhat out-of-date. Several years ago, the Swiss changed the law to allow reservists who live no more than X km from an approved armory to store their weapons at an armory outside their home. Such armories are available in most cities. I don't know how many people have taken them up this new option (it is probably still true that most weapons are stored at home). Also, the official guidance is that service weapons should not just be locked but disassembled in the home with the barrel stored in a separate part of the home from the other components to make theft and misuse more difficult. Both the armory option and recommendation that weapons be disassembled speak to the fact that service weapons are intended for national defense, but are not generally anticipated to be used in personal self-defense. Dragons flight (talk) 08:12, 9 January 2017 (UTC)

Thanks for the update. I primarily remembered my brother in law's joy at finally being able to return the rifle when he passed some age mark a few years back. --Stephan Schulz (talk) 09:57, 9 January 2017 (UTC)

Indeed. Alansplodge (talk) 22:35, 8 January 2017 (UTC)

Eugenics is not really as dead as people like to say - after all, cousin marriage is still prohibited, on rather scant evidence, in many areas. More dramatically, abortion law often carries an exception for rape or incest, which seems like quite a crude way to estimate the psychological burden for the woman but would appear to have a eugenic motivation also. There are also eugenic aspects to the sperm donor industry, and I'd hazard a guess that the eugenic potential of computer dating sites, and their proprietary algorithms, is likely unrivalled in history.

That said, the idea of eugenics is still not merely stupid but palpably counterproductive. A monoculture can work well in the short term, but a changing environment requires access to a broad gene pool. With the present level of ecological disruption, we see hybrid species forming all over the world - killer bees, hybrid West Nile carrying mosquitoes that bite humans and birds alike, and many other invasive species with hybrid roots. This should be a tip-off that organisms are casting about far and wide for new genes to deal with new environments. In the case of humans, of course, there are no other species to work with, but there is a broad gene pool in Africa. As a result we see "Recent African origin of modern humans" migrations of Homo erectus, then Homo heidelbergensis, then Homo sapiens. In each case, evolution has gone back to the deep end of the gene pool to pull out a new species. One of my many crazy ideas is that evolution could do this again relatively soon; that "Pygmies" such as the Twa have superior thought-to-mass ratios and would inevitably be selected for in any sort of interstellar dispersal. In any case, it should be clear that a program of rigorous eugenic purification is only a road toward irrelevance and perhaps even extinction. Wnt (talk) 16:00, 8 January 2017 (UTC)

"This should be a tip-off that organisms are casting about far and wide for new genes to deal with new environments"? That would suggest that evolution is driven by some sort of intelligent plan - which, I'm sure you know, is not how it works at all. Richerman (talk) 16:58, 8 January 2017 (UTC)

It's difficult to talk about evolution without it sounding that way, similar to how we say "the Sun rises" versus "the Earth rotates so that the Sun becomes visible at our location". It can be done, but it's painful and time consuming. StuRat (talk) 17:04, 8 January 2017 (UTC)

Well that may be so, but I think the statement above is a step too far for a science reference desk. Richerman (talk) 17:17, 8 January 2017 (UTC)

@Richerman: Oh, to be sure, I was speaking in a colloquial and, in my opinion alone I suppose, colorful style. Nonetheless, the "breadth of the net" so to speak with which organisms "cast about" is indeed potentially modifiable by selective mechanisms. For example, the SOS response in bacteria allows individuals to decide on a higher mutation rate in the hope (speaking only poetically, sure, bacteria don't hope) that the potential adaptive benefit outweighs the clear and present danger. There are other claims of adaptive mutation... these are generally seen as dubious, yet I continue to suspect that the phenomenon of DNA methylation is not merely a short term or even short term transgenerational form of epigenetic inheritance, but also maybe a method of designating genes for preferential mutation, even preferential types of mutation. But in the present situation, behavior might be more amenable to modification: organisms exposed to an unusually broad range of landraces in a disrupted environment might choose to discriminate less in seeking a visibly similar mate, for example, causing the degree of genetic diversity within each local population to increase, and permitting a more rapid reassortment of available genetic material. Assortative mating and disassortative mating are only extreme approximations, after all, and that behavior is as much the decision of the individual as anything can be. Wnt (talk) 18:54, 8 January 2017 (UTC)

One problem with eugenics, or any system where people "pick winners", really, is that people are prone to make bad selections. In the case of sex selection, many places may pick disproportionate numbers of males, messing up the fabric of society. Or we may choose the tall, until people become so tall that it causes medical problems. Or we may choose the thin, resulting in people with inefficient digestive systems, and mass starvation when food supplies are low, and overuse of land for farming at normal times. Even supposed defects, like autism or bipolar disorder seem to produce individuals with extraordinary abilities. StuRat (talk) 16:47, 8 January 2017 (UTC)

You may enjoy reading about plant breeding and animal husbandry and artificial selection. Maybe inbreeding depression or a hybrid vigor. Also related are genetic diversity, founder effect, and sexual selection. SemanticMantis (talk) 17:49, 8 January 2017 (UTC)

So eugenics do not work cause inbreeding make more problems? Some answers (example Swiss gun laws) confuse me, what is the link to eugenics? Also what do evoltion scientist say about eugenics and discrimation? --Curious Cat On Her Last Life (talk) 13:14, 11 January 2017 (UTC)

Yes, inbreeding is THE big problem associated with eugenics of any sort. (Also the fact that many traits which people thought were genetic actually turned out to be mostly cultural, and thus attempts to change them by means of eugenics proved ineffective.) 2601:646:8E01:7E0B:6CD5:FDD3:C2B8:18E8 (talk) 14:03, 11 January 2017 (UTC)

Vancouver cold this winter

Why has Vancouver in Canada been cold so far this winter? — Preceding unsigned comment added by Uncle dan is home (talk • contribs) 18:08, 8 January 2017 (UTC)

'Cause of the Jet Stream. Latest jet stream weather chart for Vancouver Island. Oh, and before any one says that ain’t cold. It is in comparison that Vancouver normally benefits from the Pacific winds that bring both warmth and a hell of lot of winter rain. Don't understand why Bigfoot bothers to live there in such a terrible climate. --Aspro (talk) 18:27, 8 January 2017 (UTC)

To amplify a bit, the jet stream tends to divide warm and cold air masses, as a result of the thermal wind relation. Unfortunately our thermal wind article isn't very good.

Cliff Mass discusses the recent situation for your area in a blog post here although it focuses more on the "what" than the "why." You could try following up with Cliff in a blog comment or by email. Shock Brigade Harvester Boris (talk) 18:41, 8 January 2017 (UTC)

There is an idea of "warm oceans, cold continents" that has been floating around a few years [6]; I remember seeing it had been gaining a bit more traction lately but it is still by no means widely accepted. Wnt (talk) 19:08, 8 January 2017 (UTC)

Don't know if this is an over simplification but when the jet stream is overhead, it drags bad (or severe changes of) weather along with it. Of-cause, we all know that there is no such thing really as 'bad weather' just the wrong clothing. Suitably fitted, the OP will be as snug as a bug in a rug. --Aspro (talk) 19:22, 8 January 2017 (UTC)

Or, a better way of putting it is, what's bad weather for the trucker can be good weather for the farmer. 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 03:44, 9 January 2017 (UTC)

Maybe it's not related, but New Zealand has been experiencing an unusually cold and windy summer since mid-December. Swimming pools are noticing a reduction in attendance. Akld guy (talk) 21:11, 8 January 2017 (UTC)

What are these little spikes on the beach?

I was at a beach recently (on the Atlantic Ocean) and saw these little spikes all over the edge of the water. This one is probably just under 1" but most are a bit smaller. What is it? — Rhododendrites ^talk \\ 21:05, 8 January 2017 (UTC)

We have an article on Lanice conchilega or the Mason Worm that cements sand grains together like this. What part of the world do you live in and maybe we can home in to the actual critter. Also, as you have a camera maybe you can dig one up a photo it.--Aspro (talk) 21:20, 8 January 2017 (UTC)

Umm....======> ? --Stephan Schulz (talk) 21:28, 8 January 2017 (UTC)

I assume he means to photograph the part currently below the surface. StuRat (talk) 21:36, 8 January 2017 (UTC)

I parsed "one" as referring to the camera. Damn grammatical ambiguity! --Stephan Schulz (talk) 21:47, 8 January 2017 (UTC)

The picture was taken in Rhode Island, USA (geotagged if a map is helpful), but I don't live near there so can't go back to dig. :/ — Rhododendrites ^talk \\ 21:39, 8 January 2017 (UTC)

Hmmmm. That mason worm might just be it! this picture I found when googling looks awfully similar -- just without the top part. That's pretty far from my theory -- that some kind of organic material in the ocean froze and accumulated with the outgoing tide... or something. :) — Rhododendrites ^talk \\ 21:59, 8 January 2017 (UTC)

Had a similar question about things found on the beach a short while ago. Mysterious beach blobs and the OP got confirmation from emailing the images to Scripps Institution of Oceanography. Don't be shy! Email them today. At low tide there is little point in keeping their tentacles out and displayed. P.S. That is a high quality image. Without it being so crisp and sharp I wouldn't have had a clue as to identification for something so very small. It is clear enough to discount File:Type I fulgurites Florida 1.jpg etc. --Aspro (talk) 22:20, 8 January 2017 (UTC)

January 9

Alcohol-based hand sanitizer

Does alcohol-based hand sanitizer lose alcohol content to a significantly degree over time? If so, is it known how fast alcohol content is lost? In a half-used bottle of hand sanitizer, does the existence of a significant volume of air-filled space in the bottle increase the rate of alcohol content loss? --100.34.204.4 (talk) 04:44, 9 January 2017 (UTC)

If left open, then yes, the alcohol, being more volatile, will evaporate first. But the amount of air in any portion of a sealed bottle won't hold much of the total alcohol volume as partial pressure. I suppose continuously opening the bottle top would allow the alcohol to escape at each occurrence, cumulatively reducing the percentage by a significant amount, but hand sanitizer bottles are typically designed so they don't require that. StuRat (talk) 05:10, 9 January 2017 (UTC)

Steam locomotive speed

What maximum speed a train hauled by a steam locomotive could attain? --IEditEncyclopedia (talk) 06:09, 9 January 2017 (UTC)

About 200 km/h (125 mph). See Land_speed_record_for_rail_vehicles#Steam. Notably, the world record holder was going downhill at the time and the engine broke in the process. The level grade record holder is not far behind. Someguy1221 (talk) 06:16, 9 January 2017 (UTC)

If the "could" is a question about possibility, not historical reality, then I suspect the answer would a lot higher for a purpose-build race machine - I see no particular reason why a train driven by e.g. steam turbine shouldn't be able to beat that. --Stephan Schulz (talk) 08:59, 9 January 2017 (UTC)

Here is one reason. See Hunting_oscillation. So it could be done but you'd need special rail tracks as well. 196.213.35.146 (talk) 10:18, 9 January 2017 (UTC)

Yes, but that is not caused by the particular motive force - as the other records show, a conventional train on conventional tracks can go over 300 km/h. --Stephan Schulz (talk) 10:28, 9 January 2017 (UTC)

The Mallard set a record for steam of 202.58 km/hr (125.88 mph) in July 1938. That record was never broken. Akld guy (talk) 09:19, 9 January 2017 (UTC)

False precision. The dynamometer-car record was only read in whole miles per hour: that's 126 mph. — Preceding unsigned comment added by 69.159.60.210 (talk) 08:03, 10 January 2017 (UTC)

No doubt you have a reference for that claim. Akld guy (talk) 03:02, 12 January 2017 (UTC)

Classical steam locomotives (reciprocating engine, direct drive) have a very large reciprocating mass. This makes it very hard to have their wheels turn at more than about 10 revolutions per second. To go fast, they need big wheels; Mallard's driving wheels were 6 ft 8 in (2.032 m) in diameter and making them much bigger would be hard and give poor acceleration.

The speed could be increased by, for example, using a steam turbine and electrical transmission and some of these locomotives were indeed build, but the technology only became mature in the 1930s. By then, some countries, like the UK, still tried to push the speed of steam (building locomotives like the Mallard), while others like Germany focussed on diesel-electric propulsion (Fliegender Hamburger) or, like Italy, electric propulsion (ETR 200). Soon it became obvious that the future of fast trains would be electric (although diesel would play a transitional role) and development of fast steam locomotives stopped. PiusImpavidus (talk) 10:24, 9 January 2017 (UTC)

Also, while steam trains could reach 126 mph, they could only maintain such speeds for a few minutes before things would begin to fall apart -- in fact, during that record run, the Mallard actually suffered a broken big-end bearing and a hotbox (both due to frictional heating of the parts from overspeeding). Diesel and electric trains, on the other hand, could maintain their maximum speed indefinitely as long as the track was clear -- which meant a higher average speed even if the maximum speed was the same. Add to this better low-end torque with the electric transmission (hence better acceleration) and a lower center of gravity (hence higher speeds around curves) and you can see why fast steam trains didn't see any further development. 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 12:50, 9 January 2017 (UTC)

I remember reading, back in the 1980s when I professionally edited a locomotive-centred publication, that in contrast to Mallard's official record-breaking but somewhat self-destructive run (alluded to by Someguy1221, Akld guy, PiusImpavidus and 2601), contemporary US passenger express locos not infrequently ran at up to 120mph without problems, and could readily have pushed the record beyond that of Mallard had it been desired. I suspect little publicity was sought for these performances because they were probably done unofficially to make up time from late running, and the record was not pursued on either passenger or test runs for fear of frightening off customers. (Sadly, the extensive railway library I built up back then was the property of my employers, not myself, so I have long since lost access to it.) {The poster formerly known as 87.81.230.195} 2.122.62.241 (talk) 23:42, 9 January 2017 (UTC)

Weeeeellll...it's possible, but since the records don't exist, it's hard to say for certain. The experimental PRR S1 (only one built) was reported in Popular Mechanics to have exceeded 133 mph, and various sources have made claims for speeds as high as 156 mph. The Milwaukee Road class A locos were designed for a cruise in excess of 100 mph and a top speed of at least 120 mph (and probably could do slightly better than that, though again we don't have official records). The Milwaukee Road class F7 locos were even faster and more powerful, expected to exceed 100 mph in daily scheduled service and having been observed at at least 125 mph.

As our article notes, the F7s had to maintain the fastest average speed of any scheduled steam locomotive in history, completing the 78.3 miles between Portage and Sparta (Wisconsin Washington) in 58 minutes, for an average stop-to-stop speed of 81 mph. TenOfAllTrades(talk) 22:23, 10 January 2017 (UTC)

You mean Sparta, Wisconsin -- there's no Sparta in Washington, and the F7s (to my knowledge) were never used on the Olympian Hiawatha (the only Milwaukee train going to Washington). 2601:646:8E01:7E0B:6CD5:FDD3:C2B8:18E8 (talk) 04:00, 12 January 2017 (UTC)

Yes, definitely. Fixed! I also entirely forgot the PRR T1s, for which there are anecdotal claims of operation at speeds up to 140 mph. TenOfAllTrades(talk) 04:06, 12 January 2017 (UTC)

There's some mention here [7] of others possibly exceeding the speed. It also mentions how other stuff like DRG Class 05 seems to have come very close. Nil Einne (talk) 15:01, 11 January 2017 (UTC)

Feynman Lectures. Lecture 6 (6-3, 6-4) [8], Lecture 41 (41-4) [9], Lecture 43 [10]. Probability = 33%

According to the example of Lect. 6 we can calculate the probability of distance after 30 steps with length S_rms=1. The probability to go farther σ = P(D>σ) = $\int _{-\infty }^{-\sigma }p(x)\,dx+\int _{+\sigma }^{+\infty }p(x)\,dx=2\int _{+\sigma }^{+\infty }p(x)\,dx=2\int _{+\sigma }^{+\infty }{\frac {1}{\sigma {\sqrt {2\pi }}}}\,e^{-x^{2}/2\sigma ^{2}}\,dx$.
For σ=S_rms√30 we have P(D>σ)=0.317.
If the step is fixed as +1 or -1 , then we have the probability = 0.362 JPGxmcd.

According to my previous question [11] if we have e.g. 100 atoms in 100 m³ the probability not to find any atom in 1 m³ = (99/100)¹⁰⁰ = 0.366.

According to Lecture 43 (43-1) the probability that the molecule avoids a collision for a time equal to τ (average time between the collisions) is e⁻¹≈0.37.

Is there any connection between all these probabilities?

Username160611000000 (talk) 11:01, 9 January 2017 (UTC)

• You wrote yourself that one is some value of the error function, another is 0.99^100 and the last is exp(-1). So no.

The closeness of the last two can somewhat be explained by $\lim _{n\to +\infty }(1+a/n)^{n}=\exp(a)$. Tigraan^{Click here to contact me} 16:14, 9 January 2017 (UTC)

• • Thank you very much. Username160611000000 (talk) 18:08, 9 January 2017 (UTC)

Feynman Lectures. Lecture 43. Ch.43-6 Thermal conductivity [12]

...

The thermal conductivity κ is defined as the ratio of the rate at which thermal energy is carried across a unit surface area, to the temperature gradient:

${\frac {1}{A}}{\frac {dQ}{dt}}=-\kappa {\frac {dT}{dz}}.$(43.41)

Since the details of the calculations are quite similar to those we have done above in considering molecular diffusion, we shall leave it as an exercise for the reader to show that

$\kappa ={\frac {knlv}{\gamma -1}},$

— Feynman • Leighton • Sands, The Feynman Lectures on Physics, Volume I

Using arguments of Ch. 43-5 I try next: $J={\tfrac {n_{\text{hot}}\cdot v_{\text{hot}}\Delta T-n_{\text{cold}}\cdot v_{\text{cold}}\Delta T}{\Delta T}}$

If . . $n_{\text{hot}}=n_{\text{cold}}=n$ . . we have $J=n(v_{\text{hot}}-v_{\text{cold}})$

$-(v_{\text{hot}}-v_{\text{cold}})={\tfrac {dv_{a}}{dx}}\Delta x={\tfrac {dv_{a}}{dx}}\cdot 2l$

${\tfrac {d(v_{a})^{2}}{dx}}\sim {\tfrac {dT_{a}}{dx}}$

$m{\tfrac {d(v_{a})^{2}}{dx}}=3k{\tfrac {dT_{a}}{dx}}$

$m{\tfrac {2vdv_{a}}{dx}}=3k{\tfrac {dT}{dx}}\Rightarrow {\tfrac {dv_{a}}{dx}}={\tfrac {dT}{dx}}\cdot {\tfrac {3k}{2mv}}$

$\therefore J=n(v_{\text{hot}}-v_{\text{cold}})=-n{\tfrac {dv_{a}}{dx}}\cdot 2l=-n{\tfrac {dT}{dx}}\cdot {\tfrac {3k\cdot 2l}{2mv}}$
$=-{\tfrac {dT}{dx}}\cdot {\tfrac {3nkl}{mv}}=-{\tfrac {dT}{dx}}\cdot {\tfrac {3nkl{\tfrac {v}{2}}}{mv{\tfrac {v}{2}}}}.$
$J\cdot {\tfrac {mv^{2}}{2}}=-{\tfrac {dT}{dx}}\cdot {\tfrac {3nklv}{2}}$
$J\cdot {\tfrac {mv^{2}}{2}}={\tfrac {dN}{dt}}{\tfrac {1}{A}}\cdot {\tfrac {mv^{2}}{2}}={\tfrac {dQ}{dt}}{\tfrac {1}{A}}$

$\therefore {\tfrac {dQ}{dt}}{\tfrac {1}{A}}=-{\tfrac {dT}{dx}}\cdot {\tfrac {3nklv}{2}}$.

$(\gamma -1)=2/3$

Is it correct ? I'm not sure that in 1-dimentional case we can write mv²=3kT. For 1 degree of freedom we have 1kT.

Username160611000000 (talk) 18:05, 9 January 2017 (UTC)

Why are the leaves still red?

In January, a tiny plant in my yard still has red leaves. They look like maple leaves, specifically the Acer pseudoplatanus photo with that article, and there are maple trees across the street. However, full-size trees have pretty much lost their leaves, or at least the ones left on trees have turned brown. This plant, a couple of inches tall, is even red below the leaves (the "trunk"). I never saw that.— Vchimpanzee • talk • contributions • 22:11, 9 January 2017 (UTC)

Were the leaves green before? Apparently the color leaves turn depends on what was in them when the chlorophyll dies off, apparently red leaves have left over "food" in them while brown leaves are more depleted. Vespine (talk) 22:43, 9 January 2017 (UTC)

A further possible factor: being so small, the plant may be in a more benign microclimate than the conditions to which nearby full-sized trees are overall subject. The article Deciduous may point to some clues as to why your yard-sheltered plant is privileged.

Re the trunk/stem, I've casually noticed myself that some saplings tend to have thinner bark containing a degree of chlorophyll, as contrasted to more mature specimens of the same species, so the sapling's bark can be expected to emulate the leaves' colour changes. {The poster formerly known as 87.81.230.195} 2.122.62.241 (talk) 23:55, 9 January 2017 (UTC)

There are a number of maple cultivars that have red leaves year round, see for example the later parts of Acer palmatum article. If it has red leaves year round then it may be either one of those, or a natural mutation. Watch that plant for a few years, and see if the trait was transient or persists. Dr Dima (talk) 03:07, 10 January 2017 (UTC)

Poinsettias are prized for that behavior. StuRat (talk) 04:21, 10 January 2017 (UTC)

Ah, but the red bits of a poinsettia are bracts rather than leaves. Alansplodge (talk) 13:03, 11 January 2017 (UTC)

From our article: "a bract is a modified or specialized leaf". StuRat (talk) 16:34, 11 January 2017 (UTC)

New shoots of many plants are red. As TPFKA says, trees do slightly different things based on their age/height/microclimate/position in the canopy. Generally speaking, understory deciduous temperate trees will have both earlier bud break and keep their leaves longer. This change in phenology is thought to take advantage of the extra light before the canopy_(biology) closes and after it has left in the autumn. Here is a really great freely accessible article on the topic: Differences in leaf phenology between juvenile and adult trees in a temperate deciduous forest Augsperger and Bartlett (2003). All this is to say: it is perfectly reasonable to expect to see seedlings/saplings keep their leaves longer than their full-sized peers. SemanticMantis (talk) 17:24, 10 January 2017 (UTC)

Where can you drive through a redwood?

I didn't find anything on Wikipedia using the normal methods, but Chaz Henry on KKOV says you can't do it any more. A storm has knocked down that tree. I don't know who Chaz Henry is because he never identifies his employer, but sources for this should be easy to find. However, I don't know what Wikipedia article would require updating.— Vchimpanzee • talk • contributions • 22:13, 9 January 2017 (UTC)

That would probably be the Pioneer Cabin Tree in Calaveras Big Trees State Park. This tree has been all over the local news in Northern California. For example: Remembering California’s storm-toppled historic Pioneer Cabin Tree (from the San Jose Mercury News, January 8, 2017).

I think I mentioned earlier this weekend about how bad the weather was - it's been really wild out there!

Nimur (talk) 22:53, 9 January 2017 (UTC)

Interested readers, see also: the Wawona Tree and the rest of the trees on the list of largest giant sequoias; and the Chandelier Tree, which is a close relative, a Coast Redwood. Nimur (talk) 22:56, 9 January 2017 (UTC)

One thing I haven't seen with the pictures that were published: did the Pioneer Cabin Tree crack at the height of the car tunnel? I'm thinking that digging a tunnel through a sequoia may be cool for a hundred years, but in sequoia terms, it's pretty much a killing blow? Wnt (talk) 00:20, 10 January 2017 (UTC)

Comparing these two pics, taken from near the same vantage point (note the large block of wood on the right side), it looks like it fell backwards from its burn-marked side and the top part of its roots ripped out. One problem with sequoias is that they don't have a particularly sturdy root system. [13][14] ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:24, 10 January 2017 (UTC)

There are several drive-thru trees in the Redwood Forest in far Northern California. [15] Killiondude (talk) 01:02, 10 January 2017 (UTC)

Our article links to Chandelier Tree but mentions it is a "coast redwood not a giant sequoia". (Also mentioned by Nimur above.) Looking at the above list, the species isn't mentioned. A quick search didn't find the species for the other two, so I stopped looking. I get the feeling they're probably coast redwoods though. Nil Einne (talk) 06:08, 10 January 2017 (UTC)

A simple search finds [16] appears to be the person you're referring to but I'm not sure the relevance of his identity to the question. Nil Einne (talk) 05:11, 10 January 2017 (UTC)

He wouldn't be the only news source reporting this, so it's not that important. We could assume others reported the same tree.— Vchimpanzee • talk • contributions • 16:15, 10 January 2017 (UTC)

Not sure why there's need to assume anything. Nil Einne (talk) 19:14, 10 January 2017 (UTC)

As for giant sequoias tunneled through, see this page. --69.159.60.210 (talk) 08:08, 10 January 2017 (UTC)

Engineering question: fit, clearance and tolerance

In reference to something written here (but copied and pasted here), I wonder how to consider this because, in my mind, I've got it backwards:

"When two parts are to be assembled, the relation resulting from the difference between their sizes before assembly is called a fit. A fit may be defined as the degree of tightness and looseness between two mating parts."

The important terms related to the fit are given below:

Clearance

In a fit, this is the difference between the sizes of the hole and the shaft, before assembly, when this difference is positive. The clearance may be maximum clearance and minimum clearance. Minimum clearance in the fit is the difference between the maximum size of the hole and the minimum size of the shaft.

Interference

It is the difference between the sizes of the hole and the shaft before assembly, when the difference is negative. The interference may be maximum or minimum. Maximum interference is arithmetical difference between the minimum size of the hole and the maximum size of the shaft before assembly. Minimum interference is the difference between the maximum size of the hole and the minimum size of the shaft."

I have underlined the part that I don't understand and italicized the corresponding part that I do understand. In terms of what I do understand, interference is when there is what we'd colloquially refer to interference; in other words, item X interferes with item Y. So minimum interference would be a maximum hole and a minimum shaft attempting to pass through that hole. But what I don't understand is why minimum clearance is maximum hole with a minimum shaft attempting to pass -- to be, this seemed to provide the maximum (magnitude of) clearance as 'clearance' is understood colloquially. I suppose it could be a typo, but more likely, I speculate it's merely some mathematical convention of assigning clearance with a negative, and so it's the inverse of what may appear to make sense colloquially -- or perhaps I've just got it more wrong than I think. Thanks to whomever is able to help. DRosenbach ^{(Talk | Contribs)} 23:23, 9 January 2017 (UTC)

I agree that Minimum clearance in the fit is the difference between the maximum size of the hole and the minimum size of the shaft seems to be a lazy cut and paste. perhaps they just meant maximum. Greglocock (talk) 06:34, 10 January 2017 (UTC)

I also agree. The source of the error is Indira Gandhi National Open University whose website provides no general e-mail address, only telephone numbers. (One might try contacting directorsoss@ignou.ac.in). Someone near New Delhi could inform IGNOU politely that the mistake in their course material needs correcting. Blooteuth (talk) 12:47, 10 January 2017 (UTC)

You are right, they meant to write "maximum clearance in the fit". Clearance is positive, there is no weird sign-flip convention. Here is a more clear definition of min/max clearance, with a worked example [17]. Here [18] is another definition of "clearance", which is synonymous with the maximal clearance of the previous ref.

I'm not an engineer, but I'd think relevant definitions of clearance should be added to Engineering_tolerance. Engineering_fit uses the categorical notion of "clearance fit", but does not give any info on clearance as a quantity.

Perhaps this use of min/max clearance is slightly deprecated, but persistent? Because the quality and number of references is surprisingly low... SemanticMantis (talk) 15:47, 10 January 2017 (UTC)

January 10

Feynman Lectures. Lecture 43. Lecture Summary [19]

...

${\text{The current of particles / area sec.}}=-{\frac {1}{3}}lv{\frac {dn_{a}}{dx}}=-\mu kT{\frac {dn_{a}}{dx}}=-D{\frac {d}{dx}}({\frac {n_{a}}{n_{0}}})$

— Feynman • Leighton • Sands, The Feynman Lectures on Physics, Volume I

Can you show how did he get ${\frac {n_{a}}{n_{0}}}$ ? In Lecture 43 he wrote $D={\tfrac {1}{3}}lv$ , $D=\mu kT$ , but never $D=\mu kT\cdot n_{0}$. Username160611000000 (talk) 09:43, 10 January 2017 (UTC)

How is gluten-free flour made?

How is gluten-free flour made? Since gluten is supposed to give bread its shape and structure, do gluten-free products taste as good as the traditional wheat/barley/rye products? Also, since some people eat gluten-free because of health risks of eating gluten-laden foods, can they just switch to rice? The gluten-free diet article just points out that wheat/barley/rye contains gluten, not rice or cauliflower (which can be made into a rice-like powder) or quinoa. 66.213.29.17 (talk) 17:54, 10 January 2017 (UTC)

It's as you say: gluten-free flour is made from gluten-free plant species [20] Dr Dima (talk) 19:04, 10 January 2017 (UTC)

Gluten-free bread is a huge area of research! You can find information on the rheology of GF bread, crumb characteristics, moisture, and many other aspects of many formulations. You can even see images from scanning electron microscopy, and analysis of loss modulus (e.g. [21]). Anyway, as for the taste: nothing beats some personal experimentation, as taste is somewhat subjective. However, we do have scientific research on that as well:

"Breads with legume flours showed good physico-chemical characteristics and adequate sensory profile" [22].

"Panellists commented that this bread "looked more like real bread" and that the loaves had "loaf volume and crust color similar to wheat bread" [23] SemanticMantis (talk) 20:07, 10 January 2017 (UTC)

Without gluten you need a substitute to hold the bread together. Eggs are one option. See [24]. StuRat (talk) 23:12, 10 January 2017 (UTC)

Is it scientifically proved that menstruation causes women to be irritated or nervous or it's a myth?

If it's true, then what is the physiological / psychological (psychophysiological) explanation for that? 93.126.88.30 (talk) 20:03, 10 January 2017 (UTC)

See premenstrual syndrome, and the second reference cited there [25]. Here are a few relevant scholarly references as well [26] [27]. There is much variation in the mood and affect of individual women during different phases of the menstrual cycle, but real changes in mood (and hormones, and physiology) do occur. SemanticMantis (talk) 20:17, 10 January 2017 (UTC)

Earth Axis Axial Precession

I have a question about the Wikipedia article on Earth axis axial precession. This article depicts this precession as going in a counter-clockwise direction as projected on the celestial sky. But an Astronomy Online article depicts this precession as going in a clockwise direction on the celestial sky. Which is correct? Jfandrus57 (talk) 21:59, 10 January 2017 (UTC)

Some diagrams can be ambiguous, but I think our article is correct. Which article shows it clockwise? Dbfirs 22:31, 10 January 2017 (UTC)

By way of an independent confirmatory source, I have here A Field Guide to the Stars and Planets, 1964 edition by Donald H. Menzel. On page 330 is a diagram showing the north celestial pole precessing anticlockwise against the fixed stars, the same as is shown in this section of the Wikipedia axial precession article (and the dates in the diagrams also agree).

Side comment: on first viewing the top diagram in that article, my initial reaction was that it showed precession going the other way. Once I thought about it I realized that this is because when it draws a reference circle to illustrate the precession, it's shown from the other side, looking toward the Earth rather than toward the stars. Nothing's ambiguous there, but I did find it misleading and I wonder if it might be better to substitute a different diagram or else add some words of explanation. --69.159.60.210 (talk) 05:39, 11 January 2017 (UTC)

January 11

Physicists vs. Mathematicians

Am I the only one finding the new proposed redefinition of SI base units utterly hilarious ? I just can't help but chuckle when I think about what would happen if mathematicians were to convene one day and utter sentences like: ``One, 1, is the unit of numbers; its magnitude is set by fixing the numerical value of the Archimedes constant π to be equal to exactly 3.1416`` — I mean, seriously !? 79.113.235.103 (talk) 05:31, 11 January 2017 (UTC)

I don't know, I've seen some intensely complicated definitions of 1 coming from mathematicians. Someguy1221 (talk) 06:49, 11 January 2017 (UTC)

Probably categorists. --Trovatore (talk) 08:38, 11 January 2017 (UTC)

• Well, just look at the Principia Mathematica by Alfred North Whitehead and Bertrand Russell, which defines basic arithmetic in terms of extremely detailed symbolic logic and a kind of variant of set theory. Famously, it takes hundreds of pages to reach a proof that 1 + 1 = 2. Smurrayinchester 08:46, 11 January 2017 (UTC)

Actually, the International Union of Pure and Applied Physics really did suggest in 1999 that the number 1 should become an SI unit under the name "uno", with symbol U: it's still on their website archives here. The idea was to make it easier to express dimensionless quantities in a less language-dependent way; so instead of saying "5 parts per million" (5 ppm), you'd say "5 microunos" (5 μU). The response to it was overwhelmingly negative and the idea was scrapped. As for defining 1, I think a simple enough definition would be "1 is the multiplicative identity". Double sharp (talk) 09:14, 11 January 2017 (UTC)

Not so easy, as typically multiplication is defined in terms of addition, so you need addition first. There are constructions of the natural numbers, with 1 being defined as the successor of 0. I'm sure that the friendly people at Wikipedia:Reference desk/Mathematics could tell us a lot about this. --Stephan Schulz (talk) 15:00, 11 January 2017 (UTC)

Indeed, complications arise very quickly: even in commonplace applications. For example, how is the multiplicative identity defined in non-commutative algebras? You use those every time you use matrix multiplication - and that shows up in basic tasks in elementary engineering and physics! If we define "one" as "the multiplicative identity," then our definition confusingly requires equality between the scalar value and every instance of the identity matrix. This is just one example of the semantic problem of a simple definition - we could work around it by re-defining "one" or by re-defining "multiplication" - but no matter what we try, we end up complicating the overly-simplistic original definition! Nimur (talk) 16:04, 11 January 2017 (UTC)

I think Double sharp meant something like "the one of the real numbers" or "the one of the natural numbers". There is no particular need to identify these across different structures, unless you're considering these as some embedded in others, or as embedded in some common larger structure.

There are certain structures where it is usual to identify values with their images under the canonical embeddings: Naturals -> rationals -> reals -> complex numbers, for example. We don't ordinarily distinguish between the zero of the natural numbers and the zero of the real numbers. However, when these structures are given concrete definitions in terms of set theory, the zero of the natural numbers is strictly speaking a distinct object from the zero of the real numbers. --Trovatore (talk) 20:17, 11 January 2017 (UTC)

My main point of contention was the awkward `rationalization` of certain physical constants. Like forcing them onto some Procrustes bed, and shaving off their decimals. (This makes some sense when it comes to the definitions of the meter, second, and candela, because at least there we have some relatively-nice integers, but it becomes tiresome when exaggerated). Then again, by trying to make those weird `rational` values nicer, we only end up modifying the values (and nice properties) of the units in question (like the Kelvin and the kilogram). — 86.122.66.160 (talk) 19:32, 11 January 2017 (UTC)

I don't think "nice properties" really count for much. Units are arbitrary and any set is as good as any other. You have to keep track of a few constants, but you're always going to have to do that. Computers don't mind, and humans mind only to the extent they do mental arithmetic with the values, which is not a very large extent in the first place, but to the extent that it does matter, you can't optimize for one area of endeavor without de-optimizing for another.

The point of the proposed SI redefinition is to get rid of reliance on artifacts once and for all. That's a worthy goal. They've chosen to do that in a slightly roundabout way (fixing the values of fundamental constants by definition, instead of expressing the units as products of powers of the fundamental constants). This approach is reasonable, in my opinion, because it's easier to see, oh right, Planck's constant is what I want it to be. I don't see anything hilarious about it. --Trovatore (talk) 20:03, 11 January 2017 (UTC)

Why does capital punishment have to be by lethal injection in the US?

All these problems with getting the lethal drugs, why not just put the prisoner to sleep then cut off the oxygen supply? Quick, easy and painless, or am I missing something? 2.102.186.137 (talk) 07:56, 11 January 2017 (UTC)

[1] capital punishment does not have to be by lethal injection in the U.S. The laws of the states or federal laws, depending on the jurisdiction prosecuting the crime, set forth the acceptable methods of execution.

[2] in 2014, Tennessee introduced death by electrocution as an alternative to lethal injection if the necessary drugs cannot be found.

[3] in 2015, Oklahoma introduced death by nitrogen gas as an alternative to lethal injection if the necessary drugs cannot be found. (similar, but not identical to your method)

[4] in 2015, Utah introduced death by firing squad as an alternative to lethal injection if the necessary drugs cannot be found.

[5] all of the 32 states that have the death penalty in 2017 permit execution by lethal injection. 8 states permit execution by electrocution, 11 by gas chamber, 3 by hanging, and 2 by firing squad.

In short, the legislatures legislate the methods of execution, and none have authorized your suggested method. - Nunh-huh 08:27, 11 January 2017 (UTC)

• Funnily enough, our article on cruel and unusual punishment#Capital punishment does discuss this as a possibility. As far as I can tell main problem is basically that so far, it hasn't been used. Therefore, if a criminal was sentenced to death by inert gas asphyxiation, they could go to court arguing that it was cruel and unusual (in violation of the Eight Amendment). It's therefore easier to just a technique that the courts have already allowed, even if it is a horrible approach. Oklahoma recently made this their back-up technique - if lethal injection is banned, they will start using that instead. Smurrayinchester 08:56, 11 January 2017 (UTC)
  • Asphyxiation in a pure nitrogen or argon atmosphere is not really cruel. It might actually be rather enjoyable for the victim, given the feeling of euphoria it can induce. Double sharp (talk) 10:22, 11 January 2017 (UTC)
    • Sure, but you would probably have to prove that in court since there's no precedent for its use. Courts already allow lethal injection, so it's the easier option. Smurrayinchester 11:04, 11 January 2017 (UTC)

Indeed, the bar is not whether you or I think something is "cruel and unusual." In the United States, the policy is for the court with appropriate legal standing to make such a determination. Law of the United States is a good introduction. Most schools in our country teach the very basic concepts to all students in some form of a civics class; over the next several decade, mass-media tries to un-teach those basics by blasting abject nonsense at the citizenry. My most pointed example is the apparent refusal of most media outlets to reference American laws by their actual, correct names.

On the other hand, our president-elect has, just this morning, made a public statement suggesting that our national system of government is similar to Nazi Germany... I really cannot fathom how he expects us, the informed citizens, to parse this statement. So what do I know?

Nimur (talk) 16:31, 11 January 2017 (UTC)

For the record, the tweet-quote is: Intelligence agencies should never have allowed this fake news to "leak" into the public. One last shot at me.Are we living in Nazi Germany? (punctuation error in the original) Tigraan^{Click here to contact me} 17:52, 11 January 2017 (UTC)

Note that as hinted by the two respondents above, simply cutting off the oxygen supply isn't as simple as it sounds. In addition, depending on how you do it, it's not clear if it won't be felt if the person isn't sufficient unconscious. As mentioned above something like inert gas asphyxiation may be relatively painless but it's unclear if this is what you mean when you refer to cutting of the oxygen supply.

More to the point, if your proposal requires putting the person to sleep (I assume you mean rendering them unconscious), you've potentially defeated the purpose of what you're trying to achieve. As our article Lethal injection mentions, the drug that's most problematic to obtain is often an effective general anaesthesia. Although these by nature can also be used in single drug protocols or as part of the lethal component in multi drug protocols, if specificallly lethal components are used, these are often not so hard to obtain. Especially potassium chloride.

You need to redesign your protocol to avoid the need to put the person being executed to "sleep" before administring the lethal part. Which inert gas asphyxia potentially achieves but simply cutting of the oxygen supply somehow may not do so, if you haven't considered how you would do so and how the body will respond.

Nil Einne (talk) 14:46, 11 January 2017 (UTC)

I've always thought an overdose of insulin would be the way to go. It causes lethargy, mental confusion, then they pass out, then they die. People who almost died from overdoses of insulin didn't report any pain. And, if for some reason it needs to be reversed, like the proverbial last minute call for the governor, you can inject a glucose solution to counter it. StuRat (talk) 16:28, 11 January 2017 (UTC)

I've always thought that getting rid of the death penalty, like nearly all civilised societies have done, would be the way to go. --Stephan Schulz (talk) 18:21, 11 January 2017 (UTC)

It's a noble theory. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:35, 11 January 2017 (UTC)

This is not the first time I heard people call shitting on the graves of murder victims "noble" and "the way to go", but that doesn't make it any less wrong! 2601:646:8E01:7E0B:6CD5:FDD3:C2B8:18E8 (talk) 02:20, 12 January 2017 (UTC)

Michael Portillo presented a BBC Horizon program on TV about this . Nothing difficult - he even underwent the lose of consciousness bit himself. v=DiEJKvbpOF0. The big problem with hanging, electric chair and gas chambers is that it upsets the witnesses to the execution. Unfortunately LI does not work to well on IV drug addicts that have damaged veins, so process can be even more protracted and distressful.--Aspro (talk) 19:49, 11 January 2017 (UTC)

Why is a cocktail of drugs used?

My understanding of killing humans by lethal injection is that a cocktail of drugs is used. Why is this? I worked as a veterinary nurse to pay for me to go to university and I have witnessed many animals being euthanased. It is a simple injection of just one drug and it is so quick the animal often appears unconscious before the injection has been completed, and there never appears to be any distress. If a state must have capital punishment for humans, why can this drug not be used? DrChrissy ^(talk) 23:24, 11 January 2017 (UTC)

How do you know it was just one drug? Do you have the name of it?--86.187.171.92 (talk) 23:36, 11 January 2017 (UTC)

My personal experience having pets euthanized is that it has always been two drugs. First a sedative to knock the animal out, then a lethal dose of a barbiturate. I've seen laboratory mice, however, euthanized with just an overdose of the sedative. Someguy1221 (talk) 23:54, 11 January 2017 (UTC)

e/c Apologies. My writing above was a bit sloppy. I meant a single injection. My understanding is that humans are killed by 3 injections given sequentially which causes death over a period of time (please correct me if I am wrong). The drug I have used is lethabarb which contains pentobarbitone sodium. The article Pentobarbital has some related information including the killing of a human prisoner by a single injection of the substance. DrChrissy ^(talk) 23:57, 11 January 2017 (UTC)

@Someguy1221 There are reasons why a sedative might be given first. Some animals do not like the handling associated with intravenous injections. The vet may have given the sedative (usually an intramuscular injection which can be given extremely quickly) to calm the animal for the following intravenous injection for euthanasia. This is particularly likely if you asked to have your pet euthanased whilst you were present. No vet wants an animal to freak out at such an emotional time. Where in the world do you live? - there may be different laws on euthanasia of pets? DrChrissy ^(talk) 00:07, 12 January 2017 (UTC)

Have you read Lethal_injection#Drugs ? Not sure the question is directly answered, but it has relevant information. Vespine (talk) 00:40, 12 January 2017 (UTC)

Thanks for this. Yes, I have actually just finished reading it. The article states that several US states (11 I think) do use a single injection. Maybe I am just catching up with US legislation, but it seems to me to be such an inhumane approach to use a method that might take several hours to kill a human when there is a method out there that does this in seconds - I am not condoning capital punishment in the slightest, but if a state elects to do this, it should be humane. DrChrissy ^(talk) 00:48, 12 January 2017 (UTC)

Come on, Dylan Roof deserves to die. Humanely of course. Sagittarian Milky Way (talk) 02:50, 12 January 2017 (UTC)

Dylan Roof deserves to die, this is an opinion, not a fact. I personally think that it isn't humane to kill people at all, even if they have committed atrocious crimes. It's either "vengeance" which I don't believe in, or "punishment" which I don't believe either. I don't believe in an afterlife, so killing someone is actually closer to "letting them get away with it" than even letting them serve a jail sentence. And I live in Australia where we don't have capital punishment and there's no real evidence whatever that capital punishment is a deterrent to criminals. The ONLY valid reason I have heard for capital punishment is that it is cheap, since housing a criminal in prison with no chance of rehabilitation for the rest of their life is very expensive, and that money is better spent on people who aren't criminals. I actually agree with that reason, I would rather feed hungry children than incarcerate terrible criminals, but to a society that is a FAR harder "sell" than just saying it's a punishment. This does not even go into the REAL reason for my belief which is more about free will, but that gets very philosophical very quickly and this is not the place for a debate about opinions so I'll leave it at that. And before you try to straw man my argument, I do not at all believe people should be allowed to do anything they want or not face dire consequences for their actions, I just don't think that we as a society have actually worked out what those "dire consequences" should be, but I am quite certain killing people ain't it. Vespine (talk) 03:53, 12 January 2017 (UTC)

"He that smiteth a man, so that he die, shall be surely put to death"; "And he that stealeth a man, and selleth him, or if he be found in his hand, he shall surely be put to death"; "But whoso shall offend one of these little ones which believe in me, it were better for him that a millstone were hanged about his neck, and that he were drowned in the depth of the sea" -- God's own words regarding the death penalty! 2601:646:8E01:7E0B:6CD5:FDD3:C2B8:18E8 (talk) 04:14, 12 January 2017 (UTC)

Does an increase in your heart rate result in greater thirst on your part?

Does an increase in your heart rate result in greater thirst on your part? Also, if so, does this result in you becoming dehydrated if you don't increase your water intake? Futurist110 (talk) 23:04, 11 January 2017 (UTC)

Didnt know you could insure against your heart rate. Anyway this is a medical question that WP dont answer.--86.187.171.92 (talk) 23:34, 11 January 2017 (UTC)

I obviously meant "increase" here--not "insurance." Futurist110 (talk) 00:50, 12 January 2017 (UTC)

We don't have a policy against medical questions, we have a policy against medical advice. This doesn't seem like a request for medical advice to me. I do however think the question is malformed, I don't think increased heart rate results in greater thirst, not directly anyway, those two things are unrelated. Thirst is a response to dehydration, not a response to increased heart rate. If you increased your heart rate by doing exercise which involved sweating, that will increase your thirst but again, that's a result of hydration, not heart rate directly. Anaerobic exercise can greatly increase your heart rate for short periods of time without significantly affecting your hydration or thirst. So it's not really clear what the OP is asking imho. Vespine (talk) 00:36, 12 January 2017 (UTC)

You might also just in general be interested in reading our article on thirst. It does not mention increased heart rate at all. Vespine (talk) 00:42, 12 January 2017 (UTC)

Decimal years

In scientific journals, what does a duration of (for example) "17.8 years" mean? Is it 17 years and 8 months, or is it 17 and 8/10 years? --2606:A000:4C0C:E200:C03A:9D20:31EF:82F7 (talk) 23:57, 11 January 2017 (UTC)

In astronomy it is often the Julian year, 365.25 days times 17 and 8/10ths. Sagittarian Milky Way (talk) 02:44, 12 January 2017 (UTC)

January 12

Zeroth

I heard he had sa law, but who was Zeroth?--86.187.171.92 (talk) 00:42, 12 January 2017 (UTC)

It is "0^th" -- referencing thermal equilibrium in zeroth law of thermodynamics. --2606:A000:4C0C:E200:C03A:9D20:31EF:82F7 (talk) 01:02, 12 January 2017 (UTC)

...Actually, it precedes the first law of thermodynamics. --2606:A000:4C0C:E200:C03A:9D20:31EF:82F7 (talk) 02:01, 12 January 2017 (UTC)

Bird hipped and reptile hipped

My son and I are reading a National Geographic book. In the section on dinos, there is reference to bird hipped and reptile hipped dinos. The artical then goes on to say that modern birds are more closely related to the reptile hipped dinos than the bird hipped. 1) in what way is this so? 2) if birds are more closely related to the reptile hipped dinos, how can they have evolved from bird hipped dinos? — Preceding unsigned comment added by 76.71.158.242 (talk) 02:21, 12 January 2017 (UTC)

The articles are at Ornithischia and Saurischia. Sagittarian Milky Way (talk) 02:58, 12 January 2017 (UTC)

Ichthyornis is one of the closest animals to full bird. It too evolved from lizard-hipped dinosaurs. (not a bird ancestor, just a cousin) Sagittarian Milky Way (talk) 03:57, 12 January 2017 (UTC)

Reptile-tooth birds are so last year..

Why do nurses remove bubbles from syringe before injection to IM?

Why do nurses remove bubbles from syringe before injection to IM (intra-muscular)? I do understand why they do that before injection to IV or Intra-artery, because it can cause to air embolism but I don't understand what can be in case of injection to IM.93.126.88.30 (talk) 04:06, 12 January 2017 (UTC)