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:[[Lydia_Fairchild]] is a good example of legal issues surrounding chimerism, but not a criminal case. This [http://scholarship.shu.edu/cgi/viewcontent.cgi?article=1485&context=student_scholarship] paper on the topic of legal issues and human chimeras. It seems to be written by a law student and not peer-reviewed, but it does have many additional refs. [[User:SemanticMantis|SemanticMantis]] ([[User talk:SemanticMantis|talk]]) 15:33, 18 November 2015 (UTC)
:[[Lydia_Fairchild]] is a good example of legal issues surrounding chimerism, but not a criminal case. This [http://scholarship.shu.edu/cgi/viewcontent.cgi?article=1485&context=student_scholarship] paper on the topic of legal issues and human chimeras. It seems to be written by a law student and not peer-reviewed, but it does have many additional refs. [[User:SemanticMantis|SemanticMantis]] ([[User talk:SemanticMantis|talk]]) 15:33, 18 November 2015 (UTC)
:Since [[User:Medeis]] took it on himself to remove my comment, I'll repost it with all good cheer replaced by typical Wikipedia defensive humorlessness.
: No country assumes its court will catch every single perpetrator, so these rare differences seem like a trivial issue. The sampling of fetal DNA from the mothers is far more interesting. An example of a situation where such a technique could have been applied followed an abortion by [[Monica Lewinsky]].<sup>[http://www.washingtonpost.com/wp-srv/politics/special/clinton/stories/drama012898.htm]</sup> Had right-wing opponents of Clinton been aware of the technique, which existed even then, they might have tried to get a warrant to look for Y-DNA from the father in Lewinsky's blood in the hope of contradicting Clinton's testimony; indeed, they could technically attempt it even now, given the right legal pretext. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 01:33, 19 November 2015 (UTC)
== Wormholes and entanglement ==
== Wormholes and entanglement ==
Revision as of 01:35, 19 November 2015
Welcome to the science section of the Wikipedia reference desk.
The best answers address the question directly, and back up facts with wikilinks and links to sources. Do not edit others' comments and do not give any medical or legal advice.
How do medical professionals treat transgender people and gender-variant people?
Although transgender people may identify themselves as the opposite gender and gender-variant people may avoid the gender binary altogether, does this just apply to how medical professionals (doctors, nurses, therapists, etc) address them, or does this also apply to the reference ranges for typical men and women? If a patient identifies as female but has a male body, and as a result of the anatomy, her parents raised her as a boy and gave her a traditionally masculine name, would the medical professional treat the patient as male or female? 71.79.234.132 (talk) 02:32, 14 November 2015 (UTC)[reply]
Not about this topic, but in general terms: In my experience, when you fill out the forms at a doctor's office the first time you visit, it asks how you want to be addressed, such as title or first and/or last name. And, obviously, the doctor or other medical professional needs to be informed about anything relevant as regards your mind and/or body. Their job is to treat, not to judge. ←Baseball BugsWhat's up, Doc?carrots→ 02:43, 14 November 2015 (UTC)[reply]
Hmm, the last answer should be qualified by saying "In the US" doctors typically do what the money tells them. It wouldn't apply in countries that have a state funded health service. Richerman(talk) 10:53, 15 November 2015 (UTC)[reply]
Wnt's comment is leftist bee ess. Doctors treat patients. As a person of gender I have indeed had a doctor refuse to make eye contact with me twice, once because of a (rather benign) heterosexually contracted STD and the second time because of his religious beliefs once I mentioned I was not purely hetero. But neither refused to treat me given their obvious disdain. And had they been reported to the medical board for not treating me, or at the worst, not providing a referral, they'd have been sanctioned. μηδείς (talk) 18:24, 15 November 2015 (UTC)[reply]
What a true atrocity!! Kyrie, eleison! I am SO sorry that a stranger was not personally comfortable with you while serving you. This is OBVIOUSLY why we need social justice and communism--Sıgehelmus (Talk) |д=) 18:44, 18 November 2015 (UTC)[reply]
I think that would depend on what you mean by treat. If you mean in a behavioral sense, that would probably go on a case-by-case basis, some docs/nurses might be a bit weird about it while others would be fine(although they really should act professionally). But in the "medical" sense, I think they would treat a patient by their biological sex - male, female, or whatever stage in the transgender process. This should be obvious why - a pre-transition trans man is still anatomically female and so still has all their female bits, and so if a trans man were to have abdominal pain, doctors would still take into account that the patient has ovaries, could be pregnant, etc. Cannolis (talk) 20:44, 15 November 2015 (UTC)[reply]
I have also had plenty of primary care physicians refuse to write various prescriptions, to the point that I have had to pay for out-of-network treatment. That is simply how healthcare works in the US. (BTW, the doctor I wanted to see was in network until the advent of Obamacare. This loss of coverage had nothing to do with anyone's Catholicism.) μηδείς (talk) 04:49, 16 November 2015 (UTC)[reply]
Do the human body break down salt?
1. Do the human body break down salt before excreting it? As in, does it leave the body as NaCl or does the body break it down and the sodium and chlorine leave (either separately or together) in the form of other chemical compounds?
2. I vaguely remember having learned that salt exists the human body mostly dissolved in the urine. Is this true? 731Butai (talk) 03:16, 14 November 2015 (UTC)[reply]
Sodium chloride in solution is almost entirely dissociated into Na+ and Cl-. So in that sense, the body doesn't have to "break it down" because it's already "broken down". --Trovatore (talk) 03:20, 14 November 2015 (UTC)[reply]
Yes, I understand that. I'm asking whether the body ever separates the Na+ and Cl- ions and possibly incorporates them into other compounds (that's not NaCl). 731Butai (talk) 04:32, 14 November 2015 (UTC)[reply]
2) (I take it you meant "exits".) Yes, most salt normally exits in urine, but if it's hot and you sweat a lot, you can lose a lot that way, too. StuRat (talk) 05:18, 14 November 2015 (UTC)[reply]
Your body uses the sodium and chlorine ions separately – one obvious use is in the hydrochloric acid that dissolves things in your stomach (even in there, there's Na+ floating around, but there's less of it than there is Cl-). On a molecular level, the sodium channel on cell membranes moves Na+ in and out of cells, which is especially used in nerve cells to control how active they are, while the chloride channel (which is less understood) seems to have more to do with muscles. As Trovatore says, it's a bit meaningless to talk about compounds when you've got dissolved ions. Boil down urine, and you'd probably find molecules like potassium chloride and ammonium sodium phosphate, but these are formed by the ions combining outside the body. There are no amino acids containing chlorine or sodium atoms, so the body can't build proteins with them. (If you meant "salt exists in the human body mostly dissolved in the urine", that's probably incorrect. The body is 0.4% NaCl, which suggests a 50 kg person contains 200 g of salt. Given that you only need about 5 g a day of salt to stay healthy, that suggests that only about 5 g a day of salt - 2.5% - is excreted in urine/salt on a given day). Smurrayinchester 08:35, 14 November 2015 (UTC)[reply]
(edit conflict) As soon as you expose NaCl to water, it disassociates into Na+ and Cl- ions (unless the solution is saturated). The only "breaking down" that directly done by your body is if you ingest pure salt, in which case it disassociates as soon as it hits your saliva. As for their role in your body, their main function is as electrolytes, free ions in solution that are used to carry electric charge. Some ions are used as enzyme cofactors, but sodium and chloride don't appear to be. But there is one other neat thing your body sometimes uses chloride for. In a respiratory burst, white blood cells produce hypochlorite to kill pathogens. You might know hypochlorite as the ion in household bleach. Greenish pus is caused by the presence of myeloperoxidase, the enzyme involved in this. --71.119.131.184 (talk) 08:40, 14 November 2015 (UTC)[reply]
I can't see an answer to the OP's question above. The answer, I think, is that Na and Cl are basically handled independently after they dissociate, but the charges always have to balance. So if positive ions are excreted, an equal quantity of negative ions have to go along with them. But if for example you ingest sodium chloride and potassium bicarbonate, it would be possible to excrete potassium and chloride, leaving the sodium and bicarbonate behind. Looie496 (talk) 13:07, 14 November 2015 (UTC)[reply]
I don't think it's true that "the charges always have to balance", although that statement is a bit vague. Have to balance in what context? It's not true at the level of individual cells; cells have a membrane potential, which they maintain by constantly using energy to pump ions in and out of the cell. It is true that, if nothing is done, osmosis will eventually equalize the potentials on both sides of the cell membrane; that's why cells have to use energy to maintain it. And I don't think it's true at the level of your entire body either. The kidneys have a lot of control over the amount of electrolytes excreted in the urine. Here's a good primer on how the kidneys function. What aspect of the original question hasn't been answered, in your view? --71.119.131.184 (talk) 21:43, 14 November 2015 (UTC)[reply]
The part of the original that was not clearly answered (unless I missed something) is whether it is possible for the sodium and chloride to leave separately. And in spite of what you wrote there, it's still true that the charges have to balance. No part of the body (except the hair) can maintain more than a tiny electric charge relative to the rest of the body. The urine definitely can't be electrically charged. Looie496 (talk) 17:48, 15 November 2015 (UTC)[reply]
MacLeod prints
A very old textbook (c 1910) I have discusses on one page experiments requiring high vacuum. It refers to readings off "MacLeod prints" as needing to be under 1/1000 mm - could mean below 1/1000 mm mercury pressure??
What are MacLeod prints? 60.228.193.237 (talk) 08:53, 14 November 2015 (UTC)[reply]
Presumably something to do with the McLeod gauge. Could prints be a typo for points?--Shantavira|feed me 09:02, 14 November 2015 (UTC)[reply]
Ahah! That will be it. Thanks, Shantavira.60.228.235.225 (talk) 15:27, 14 November 2015 (UTC)[reply]
Is this the place to ask about an outer vest made from coyote fur?
How appropriate is coyote fur for such an application? Would you consider it suboptimal? I bought one for $400 and am wondering if I should return it. 69.22.242.15 (talk) 14:04, 14 November 2015 (UTC)[reply]
No, I wouldn't consider it suboptimal at all. In fact I wish I had $400 to get one. For years I've been longing to upgrade from my opossum fur vest. — Preceding unsigned comment added by 72.94.61.22 (talk) 15:34, 14 November 2015 (UTC)[reply]
I think you will find many opinions on "appropriateness": you can start by reading about North American fur trade. In many places in the United States, coyote is considered a "pest" and coyote-hunting is often very liberally allowed. This means that its fur is neither rare nor particularly valuable, and is very probably legal in most places in the United States. Compared to other animals who are hunted or farmed for fur, coyote is neither considered "fine" nor "luxurious." Mink, otter, and beaver, for example, all have denser and more durable fur; you can read list of types of fur for some more information. Whether your particular garment was legally or ethically produced is beyond the scope of our website; and whether the price you paid is appropriate ultimately depends on local economic condition. Ultimately, whether you consider it "appropriate" to wear its fur is really a matter of your personal and ethical considerations; and whatever applications you have.
I spend a large amount of time outdoors, and in snow; I would rather use a synthetic material like nylon or Gore-Tex to stay dry; and wool to stay warm. Fur smells bad when wet; and when you're out in the muck, they can find you if they can smell you.
I agree, for $400, you could certainly stay warmer and more comfortable with synthetic materials. Another issue is that fur isn't very durable. On the animal, it would be continuously replaced with new fur as the old fur falls out, but not so once it's a coat. So, it will get thinner and thinner over time. StuRat (talk) 17:41, 14 November 2015 (UTC)[reply]
A Google search for coyote fur vest suggests that $400 is on the high-side. eBay has much cheaper prices available (less than $50 for a full coat, albeit used). As noted above, optimization is going to depend on what you want to do. 99.235.223.170 (talk) 14:15, 15 November 2015 (UTC)[reply]
Yes it's a picture of a high school, but it's some stuff in the foreground which interests me?
What's the not quite raised "lane" in front of the sidewalk?, Also is there are reason for the different paving on what i assume is a crosswalk ( crossing)?
Sfan00 IMG (talk) 14:27, 14 November 2015 (UTC)[reply]
That must be a bike path by the pavement on the road. 69.22.242.15 (talk) 15:28, 14 November 2015 (UTC)[reply]
This is an example of tactile paving, for the assistance of blind and partially-sighted pedestrians. Tevildo (talk) 16:01, 14 November 2015 (UTC)[reply]
More of a bike lane, I'd think. In the USA, "bike path" often means a route that doesn't allow motor vehicles, and a lane is what we call it when bikes have a lane on the road used primarily by automobiles. The crosswalk appears to have originally been paved with brick, i.e. Pavement_(architecture)#Paver, which was later painted over, perhaps for higher contrast. SemanticMantis (talk) 16:04, 14 November 2015 (UTC)[reply]
Historic elements
On page 227 of The Progress of Invention in the Nineteenth Century by Edward Byrn, there's a list of "Elements discovered in the nineteenth century". Most of them appear in the current periodic table, a few have been renamed since their discovery (Columbium, Glucinium), two aren't elements (Didymium and Cyanogen), and Coronium is highly-ionized iron. This leaves three entries, all from 1898 - "Metargon", discovered by Ramsay and Travers, "Monium", discovered by Crookes, and "Etherion", discovered by Brush. What (if anything) are these elements called today? Helium (which doesn't appear on Byrn's list) is an obvious possibility, but confirmation will be needed. Tevildo (talk) 16:21, 14 November 2015 (UTC)[reply]
"Metargon" is probably either an experimental error, or a real element known today as a different noble gas, perhaps krypton, for which Ramsay and Travers were known, and for which Sir William Ramsay was awardee the 1904 Nobel Prize in Chemistry. I am still reading the details in On a new constituent of atmospheric air (1898) ... there is a mention and parameterization of an as-yet unidentified gas, but the authors apparently already have the name for krypton - and the given parameters don't match krypton (or any other noble gas). Perhaps the "metargon" discovery was even an experimental error.
Metargon (1898), published in Nature, seems to concur that this compound was not an element, and that the experiment found argon contaminated with carbon.
A quick search turns up a news article on etherion [1] - truly it is a wonderful substance, said to be capable of tremendous heat conduction, and... "Tho molecular velocity of hydrogen at the temperature of melting ice is 5,571 feet a second, while tbe molecular velocity of the new gas is 657,100 feet, or 105 miles a second." It is said to be obtained from crushed glass, charcoal, other substances. It notes that he stops short of calling it an element. Oddly, the McLeod gauge mentioned a few topics above is mentioned, and that article describes ways in which it can trick the unwary if a vacuum contains a gas that can condense ... I wonder if that actually has some role in this, but I don't know at all. Wnt (talk) 19:35, 14 November 2015 (UTC)[reply]
Thanks for the information so far! I see that the etherion article lists "argon, helium, neon and metargon" separately; krypton is on Byrn's list, so neither it nor helium seem like good candidates for metargon. I also now have to ask - what is "molecular velocity"? We don't have an article, although it seems to be a quantity which could be measured precisely in 1898. Tevildo (talk) 20:54, 14 November 2015 (UTC)[reply]
That would be one way to represent temperature, normalizing for molecular mass. It can also be derived from the speed of sound or the Young's modulus. We have more on the topic at particle velocity. It is a characteristic, average velocity of the ensemble - the velocity of any individual particle might fall along a Maxwellian probability distribution. Nimur (talk) 04:23, 15 November 2015 (UTC)[reply]
The key thing here is that in the Boltzmann distribution/Thermodynamic temperature (sorry, these articles are spread out in dribs and drabs ... wish someone would organize the concept better) leads to every particle having a translational energy (motion, not rotation) of 3/2 k T. This is true no matter how big they are - you picture a gas, well, sometimes a big particle coming slow bounces a little one off at huge speed, or vice versa. The relation there is kinetic energy = 1/2 m v2. That means that the square root of the difference in velocities is the ratio of the mass, which is to say, the particle has an atomic mass of sqrt(5571/657100) = 0.092 amu. This is why I tend to view this as an unusual report. :) Wnt (talk) 15:48, 15 November 2015 (UTC)[reply]
Thanks again, but I'm still not quite sure what quantity Brush was reporting. It seems reasonable to assume that it's the √(2kT/m) of the Boltzmann distribution, but Brush seems to be measuring something (the thermal conductivity?) which gives him vp to a fair number of significant figures, from which the molecular mass could be calculated; he doesn't appear to have measured the mass by more direct methods. Tevildo (talk) 18:56, 15 November 2015 (UTC)[reply]
Monium turned out to be a mixture of gadolinium and terbium. See p203 in:
Fontani, Marco; Costa, Mariagrazia; Orna, Mary Virginia (2014). The Lost Elements: The Periodic Table's Shadow Side. Oxford University Press. ISBN9780199383344.
a book that is overall all about various elemental non-/mis-/discoveries. DMacks (talk) 22:41, 14 November 2015 (UTC)[reply]
Monium (element) probably won't ever amount to more than a few-sentence stub, but if there are a few secondary refs (mine talks in some detail, not sure what Tevildo's says), it's clearly not the topic that Monium might elsewise mean. DMacks (talk) 22:59, 14 November 2015 (UTC)[reply]
Excellent book, sincerest thanks. It also reports Ramsay's disclaiming of metargon as an experimental error (page 180) and Marian Smoluchowski's identification of etherium as water vapour (page 424). My main question is answered, and my intellectual pleasures satisfied for the immediate future; I don't think that we really need articles on these elements (although the facts are available), I was mainly wondering if suitable redirects could be created - probably not, based on the information we now have. I'll leave the "molecular velocity" question open from personal curiosity, though. Tevildo (talk) 23:12, 14 November 2015 (UTC)[reply]
Thanks also for the monium addition. For the other two, metargon is probably worth mentioning in Argon. We have an article Ethereum (some sort of ersatz Bitcoin thing), and "Etherium" is the name of a (presumably-NN) video game, but I don't think any further action is necessary - perhaps a footnote in Charles F. Brush would be a possibility. Tevildo (talk) 23:29, 14 November 2015 (UTC)[reply]
The way I read it, it sounds more like Ar contaminated with CO2: "This gas [metargon] subsequently turned out to be argon in the main, but to contain carbon dioxide, owing to the use of an impure specimen of phosphorus containing carbon in removing the oxygen; but it gave us a great deal of trouble to make sure that it was not a new individual." Double sharp (talk) 13:37, 16 November 2015 (UTC)[reply]
In the Dingo article the term "agile wallaby" is used twice. Is this just adjectival overkill, or are agile wallabies a class unto themselves, as opposed to lummox wallabies? Thanks, and pinging @JackofOz: and @Iryna Harpy:. μηδείς (talk) 22:59, 14 November 2015 (UTC)[reply]
Agile wallaby. It's linked at first use in the dingo article. Deor (talk) 23:10, 14 November 2015 (UTC)[reply]
The genus 'wallaby' is extremely diverse and range in size from that of a small kangaroo to very, very small. This makes the smaller species prime targets for predators like the dingo. --Iryna Harpy (talk) 00:44, 15 November 2015 (UTC)[reply]
This brings up a bigger point. Should the Dingo article say 'Agile wallaby'? That is the proper name for that species. I ask because a while ago, somebody with a bot went through the Rena oil spill article and changed instances of 'Little penguin' to 'little penguin'. See Little penguin. His bot may have done the same to the Dingo article. He cited some WP policy, but to my mind it's bad policy, since it causes this ambiguity when the proper name is formed from an adjective. Akld guy (talk) 03:10, 15 November 2015 (UTC)[reply]
Here is the relevant guideline. This is something that has been debated on Wikipedia hard and long over the years. I wouldn't advise bringing it up again. Deor (talk) 10:56, 15 November 2015 (UTC)[reply]
Ah, thanks. You'll note I said the term was used twice, but it is actually used three times, with the usage I skipped linkified to Macropus agilis. μηδείς (talk) 18:11, 15 November 2015 (UTC)[reply]
November 15
What is the differrence between foramen and canal (anatomy)?
I read about the foramens and canal of the skull bone and I don't understand what is the difference between them, here are both of them are holes, so what is the difference between canal (e.g. optic canal) and foramen (e.g. foramen rotundum)? 92.249.70.153 (talk) 04:10, 15 November 2015 (UTC)[reply]
A foramen is any sort of hole. The word "canal" carries the implication that the thing is relatively long in relation to its diameter. Looie496 (talk) 17:37, 15 November 2015 (UTC)[reply]
Not necessarily, but the distinction between a "hole" and a "passage" is what matters. A canal (anatomy) can be a single foramen (as in the optic canal, which is identical with the optic foramen), a longer structure with foramina at each end (as in the mandibular canal, terminated by the mental foramen and mandibular foramen), or pass through many different parts of the body (as in the spinal canal, which passes through each of the vertebral foramina). A foramen is one particular hole in one particular bone. Tevildo (talk) 18:31, 15 November 2015 (UTC)[reply]
How thick of a layer of ice could every ship get through?
Including all time periods. Assuming moderate winds (quantity and quality). What kind of ship is most susceptible to having its progress stopped by ice? I can't find this easily, maybe because no one wants to be liable for a sinking but I couldn't even afford a boat much less a ship so this wouldn't be professional advice. Sagittarian Milky Way (talk) 11:21, 15 November 2015 (UTC)[reply]
The word "ship" is not all that well defined. From a coracle to the Titanic is a continuous progression, with no obvious splitting point. Looie496 (talk) 17:31, 15 November 2015 (UTC)[reply]
My father, who did a stint in the Navy, gave as the distinction that a ship carries boats (lifeboats and such). It's obviously not a perfect demarcation (presumably, a ship that loses all its boats in a storm is still a ship), but it might be a decent rule of thumb. --Trovatore (talk) 19:59, 15 November 2015 (UTC) [reply]
A line from Flip Wilson's version of Columbus' voyage: "Columbus cried, 'Lower the longboat!' - Which was really the short boat on the side of the big boat." ←Baseball BugsWhat's up, Doc?carrots→ 20:03, 15 November 2015 (UTC)[reply]
Not only what Looie said, but if you are talking about sea ice, it has to reach a threshold thickness, and this is often a result of winds or current. As stated, the question is too vague to answer. μηδείς (talk) 18:05, 15 November 2015 (UTC)[reply]
I would think a proper answer would require knowing how much force it takes to fracture ice at various thicknesses. The latest Old Farmer's Almanac has a list of thicknesses and how much weight they can tolerate - ranging from one person standing on it to a heavy truck driving on it. The data in that list don't address the OP's titled question here, but it's on a similar track. ←Baseball BugsWhat's up, Doc?carrots→ 19:42, 15 November 2015 (UTC)[reply]
Okay, clarifications: A ship is something big enough to carry it's own boat(s) (I've heard that one before, too). Sea ice says that it's new when thin and isn't solid ice until about 1 foot thick (there's a photo). So a solid layer of equal thickness like one a lake maybe might be harder than sea ice. Sagittarian Milky Way (talk) 20:41, 15 November 2015 (UTC)[reply]
You also have to consider the hull. A ship designed for speed might not have a hull strong enough to repeatedly break through ice, even if it has the power and weight to break it. Sjö (talk) 06:03, 16 November 2015 (UTC)[reply]
Including all time periods makes this a tough question. If we imagined something like (say) a Greek triereme - it's built for ramming, and therefore has an impressive bronze ram and a hull that's reinforced to survive forward impact very well - characteristics that might make it very good for breaking through modest amounts of ice...but because it's an oared vessel, once it has ice to either side, the oars would no longer be able to reach the water - and little progress could be made. Anything that relies on oars for propulsion is going to start getting into trouble long before it has to fracture the ice - simply because having lots of (say) two meter chunks floating past the hull would make rowing so difficult. In such circumstances, even if the ice were just inches thick, they might have a lot of difficulty in making headway. But whether this scenario is the absolute worst is hard to tell. Any kind of very wide - yet lightweight vessel is going to lack the momentum to break the ice on such a broad front - and such a ship might be even worse off than an oared galley. SteveBaker (talk) 00:53, 16 November 2015 (UTC)[reply]
Triremes did have sails (though they don't look very big). So they should still move without oars. And young ice might not have large chunks in it yet. Though if 1.1 inches thick was when a 180 pound man fell through in a test (referenced above) then that must still be a pain to row in unless weakened by waves or something. Sagittarian Milky Way (talk) 01:35, 16 November 2015 (UTC)[reply]
The Icebreaker article makes some interesting points which I've also seen from googling the subject. What the icebreaker does is fracture the ice and then basically plow through it. Ice does not bend very well, so even thick ice is relatively easy to get through once you have cracked it. However, icebreakers require machine power. No matter how strong a sailing ship's hull would have been, it would have been hard to keep going into only minimally fractured ice. ←Baseball BugsWhat's up, Doc?carrots→ 01:42, 16 November 2015 (UTC)[reply]
Gasoline powered electric car
Note, I'm not talking about hybrid cars or pure electric cars, as this is a very different concept. I was looking at, Integrated electric propulsion for submarines and such and wondered why was this never implemented for cars? It would eliminate the need for gearboxes, clutches, and thus having fewer moving parts making the car more reliable. So why not? ScienceApe (talk) 11:32, 15 November 2015 (UTC)[reply]
Yes, that's also how hybrid cars and diesel locomotives work, except that these marine units have two fuel-burning prime movers rather than just one. Such complexity pays off, in these far larger marine usages. Jim.henderson (talk) 11:37, 15 November 2015 (UTC)[reply]
IEP requires a prime source of power such as an internal combustion engine, a generator and at least one electric motor. In a large vehicle such as a ship, or a vehicle in which weight does not represent a significant penalty, such as a railway train, IEP provides an ideal means of propulsion. Conversely, in small vehicles like cars, and vehicles in which weight represents a significant penalty such as airplanes, the economics are very different; in these vehicles IEP does not provide an ideal means of propulsion - the economy of scale is against them. The efficiency of generators and electric motors increases with their size - if these pieces of electric equipment are to achieve high efficiency they have to generate and employ very large amounts of power. For small vehicles, the light weight and simplicity of a clutch and/or gearbox is superior to the combination of generator and electric motor. A friction clutch in a small vehicle is a very light-weight, simple and reliable element of a drive system. Once a friction clutch is fully engaged it transmits power with no losses; conversely, a generator and electric motor suffer I2R losses all the time and especially at high powers. Dolphin(t) 11:46, 15 November 2015 (UTC)[reply]
The GM Volt is, to within a whisker, an example of a series PHEV. The disadvantage for small cars is weight, because you have all the weight of a battery electric veicle, less some batteries, but plus an engine and a generator and a fuel tank etc. The series/parallel hybrid architecture, as used in a Prius, is lighter and often more efficient, as some of the power is transmitted mechanically. Various cars have been built as pure series hybrids, none are in production AFAIK. Greglocock (talk) 22:57, 15 November 2015 (UTC)[reply]
The BMW i3 is interesting, but even with the optional gasoline-driven range extender engine it doesn't use integrated electric propulsion, which is what the OP was asking about. The gasoline range extender engine still requires a high-capacity (high-cost) battery system. Dolphin(t) 10:34, 16 November 2015 (UTC)[reply]
November 16
Anticonvulsiveness as a side effect
I believe that I read some time ago about an anticonvulsant medicine that was developed for another purpose but was tested and marketed as an anticonvulsant after it was serendipitously discovered to retard epilepsy during trials. I was strongly under the impression that this was oxcarbazepine, but this page seems to say that it was originally intended to be an anticonvulsant. Our article has a nearly useless History section (because it's so short), and I wasn't sure how to search for this kind of thing on Google. Before looking at Category:Anticonvulsants, I was only aware of oxcarbazepine, levetiracetam, and phenytoin, so either it's one of those three, or I've imagined it. Levetiracetam doesn't mention history, and phenytoin apparently wasn't used for anything until it was found to be an anticonvulsant. Nyttend (talk) 01:07, 16 November 2015 (UTC)[reply]
PS, my question was "which one of these three was it, or am I misremembering/imagining something?" Nyttend (talk) 01:10, 16 November 2015 (UTC)[reply]
Hmm, I did a little reading, and both phenytoin and valproate had their anticonvulsant effects discovered after their initial discovery. But maybe you were thinking of levetiracetam. The first racetam to be discovered was piracetam, which wasn't specifically developed as an anticonvulsant drug. I think most of the other racetams were developed by just playing with piracetam's structure to see what you would get. --71.119.131.184 (talk) 07:12, 16 November 2015 (UTC)[reply]
Cursorial marsupial herbivores?
The marsupial thylacine ran like a dog, but I am unaware of any herbivorous marsupials that ran like a deer. Are there any cursorial marsupial herbivores in the fossil record? I am aware of the Diprotodont, but is seems more like a ground sloth than a gazelle. Thanks. μηδείς (talk) 04:37, 16 November 2015 (UTC)[reply]
Per Graeme, I'm pretty sure this ecological niche is filled by kangaroos and wallabies. Large-ish, fast-ish plant eaters (i.e. what Antelopes do in Africa or Deer in N. America/Eurasia)... --Jayron32 16:10, 16 November 2015 (UTC)[reply]
The OP didn't ask about that, she asked about animals with a similar gait. Since a deer runs on all 4 legs, we are looking for a marsupial that does the same. StuRat (talk) 16:42, 16 November 2015 (UTC)[reply]
Yes, I was reading the agile wallaby article and noted that the animal's head resembles that of a deer, then wondered if there were any marsupial herbivores, now or in the fossil record, with the gait of a deer. μηδείς (talk) 18:13, 16 November 2015 (UTC)[reply]
There are several common marsupials who walk on all fours, though I don't know how the patterns of the way their feet strike the ground compare to deer. Common four-legged walkers include wombats and opossum. Most Kangaroos and Wallabies are two-legged walkers, or hybrid walkers, like chimpanzees and bears (IIRC). --Jayron32 19:12, 16 November 2015 (UTC)[reply]
Right, so to sum up: there's some confusion about the termiology. kangaroos are specifically mentioned at cursorial, and their hopping gait seems to technically qualify as running, and they definitely operate in a comparable niche to deer. Cursorial is more about how often and fast the thing moves, not the gait. But the question is also about deer gait, and roos run nothing like deer! Hard to find evidence of a lack, but I think thylacine is about as close to a deer gait as you'll get. By species number, most current living marsupials are scansorial, and the cursorial ones seem to hop... You might like to look at the hips and spines of the Thylacoleo. SemanticMantis (talk) 20:47, 16 November 2015 (UTC)[reply]
I think the inclusion of kangaroos in that list needs a big fat {{CN}} tag. Hopping with two feet in unison in no way fits the definition of running. μηδείς (talk) 22:27, 16 November 2015 (UTC)[reply]
Well our definition of running is "Running is a type of gait characterized by an aerial phase in which all feet are above the ground " -- for which a kangaroo clearly qualifies. If you have a good RS that says kangaroos can't run I'm all ears. Also note that some spiders are considered cursorial, even though they don't have a long-distance locomotive gait that has all legs leave the ground at once. I means sure many spiders can hop but that's orthogonal to being considered cursorial as far as I can tell. SemanticMantis (talk) 01:40, 17 November 2015 (UTC)[reply]
Are you serious, SM? That kangaroos run is 'true', unless I prove a negative? That's not how WP or the ref desks work. It took me a whole three seconds to find Animal_locomotion#Jumping. Unless you have something to say about marsupials other than the thylacine (and one presumes its close fossil kin) you are simply being unhelpful. μηδείς (talk) 02:06, 17 November 2015 (UTC)[reply]
@Medeis: Hey, I don't care if you act like a jerk to me over policy issues, but please be civil and AGF on matters of science. It think we do have a common interest here, and you seem to be taking my words in a very negative and non-intended manner. I was trying to help, and I was being serious. So let's look at a few refs: first, kangaroos (and kangaroo rats, and some other hoppers) are considered cursorial. As I said above, that designation is not really about specific gate, but about how fast, far, and often the critter moves. Here [2] is a dissertation that discusses the cursorial frugivorous behavior of the smallest kangaroo. Here [3] is an example of a peer-reviewed scholarly article that specifically mentions kangaroos as cursorial, and here [4] is yet another. So feel free to add those to satisfy your big fat {CN} tag for the cursorial article (I would, but I'm spending my WP time on you ;)
Now, the gait question is indeed interesting. What I meant to communicate above is that our definition at running does not rule out hopping. But that could just be a matter of sloppy writing on WP The jumping section you linked does seem to consider the gait as distinct, but for all I know, some locomotion specialists do consider hopping to be a sub-class of running, since both involve all feet leaving the ground. But that's just a tangent. Going back to running per se, this (old) article [5] mentions the Tasmanian wolf, but then goes on to say
“
the diprotodont marsupials... exhibit extreme modifications for both running and jumping... the bandicoots exhibit decided cursorial modifications
”
See pages 3-4 in the article for that and further discussion of the modifications. N.B. the bandicoot article doesn't have a taxobox but it looks like they are not longer classed with the Diprotodontia, though I don't think that's relevant to the issue at hand.
I don't really care to argue about classification of gaits, but there's a few scholarly references that say that a) kangaroos are cursorial and b)bandicoots are a candidate for the marsupial that is most adapted for quadrupedal running. Hope that helps, SemanticMantis (talk) 15:43, 17 November 2015 (UTC)[reply]
I have just read Cursorial and I find this article is actually more confusing than helpful. The lede begins by indicating it means animals adapted to running. It then goes on to say "Cursorial organisms are typically adapted to long-distance running at high speeds, rather than animals with high acceleration over short distances; thus, a cheetah is considered cursorial, while a leopard is not." This is all stated without in-line citations! The only in-line citations are about spiders. It also states that all cursorial vertebrates are endotherms - what about the race-horse goanna? - I believe these can out-pace a horse, albeit for short distances.DrChrissy(talk) 15:46, 17 November 2015 (UTC)[reply]
Yes, it's in bad shape. The lead is using a common notion of "run" to mean "fast", not a specific gait, which is unfortunate, because the first link is about a specific gait, and focused on humans. Unless the reader already knows about cursorial hoppers and walkers, or knows to think of "run" as a casual, informal usage, the article gives a very wrong first impression. Maybe I'll take a hack at it tomorrow. SemanticMantis (talk) 15:57, 17 November 2015 (UTC)[reply]
One more ref, a Nature paper titled "Why kangaroos hop" [6]- it states in the abstract that are the only large marsupials with major cursorial adaptations. Very relevant to the bigger picture, and sort of hints at why we don't see any marsupials that move with a very similar gait to deer. SemanticMantis (talk) 15:52, 17 November 2015 (UTC)[reply]
This might help[7] I would use it myself but I don't have full access at the moment. In the abstract it talks about running fast OR far.DrChrissy(talk) 16:16, 17 November 2015 (UTC)[reply]
Well, to restate the question, does Australia have any animals besides the thylacine living or extinct which are evolved for cursorial behavior along the lines of a deer, an ostrich, a wolf or a human? In the strict sense, the answer "kangaroo" is obviously wrong, they are extremely adapted for saltation, not running. You mentioned [Thylacoleo]] above, but its forearms are much larger than its hindquarters, and it is obviously not adapted for running in this sense.
As for my being a "jerk" to you? That's projection, and it needs diffs, preferably at ANI. Any conflict we have is always based on trolling by third parties whom you sometimes defend but who almost always end up getting blocked. There are plenty examples of such trolls on my talkpage if anyone's in for a round of masochistic rolling in muck. I would, as you state, rather focus on the question.
I am curious if anyone can recommend a book on the fauna of Australia, living and extinct, along the lines of various mass-market illustrated books we have on extinct vertebrates, such as [8] and [9]. μηδείς (talk) 17:51, 17 November 2015 (UTC)[reply]
There are camels in Australia. They would be classed as cursorial grazers. They run with their own peculiar gait. Akld guy (talk) 19:28, 17 November 2015 (UTC)[reply]
There are quite a few other feral animals in Australia, including deer, and horses. Quite similar in idea to the ostrich is the emu. You can also find feral dogs and dingos. Graeme Bartlett (talk) 19:36, 17 November 2015 (UTC)[reply]
@Medeis: First, WP:INDENT, I think you were intending to reply to me, but you placed your comment in reply to DrChrissy. Secondly, I provided three academic journal articles and one Ph.D. dissertation that clearly and explicitly classify kangaroos as cursorial. If you don't like the kangaroo answer because they hop, that's fine. I know you also wrote "ran like a deer." But kangaroos are cursorial, according to the usage of experts in the field. So your current rephrasing makes the answer even more squarely "kangaroo".
If you want to look for marsupials that have adaptations for quadrupedal running, that's fine too, just know that that's not the same as cursorial. I thought about that too, and spent some time looking. For that case, I directed you to a peer-reviewed article that discusses the morphological adaptations for quadrupedal running in bandicoots, and I even gave you the page ref and typed up the block quote for your convenience. So I really don't know why you're getting all riled up. It's actually pretty simple: Kangaroos are cursorial marsupial herbivores. If you want a quadrupedal marsupial herbivore that runs and does not hop, look to the bandicoot. Here's a video of one bolting away rather quickly [10]. If you want a large marsupial herbivore that runs just like a deer, I think you're out of luck, but I could be mistaken. SemanticMantis (talk) 19:49, 17 November 2015 (UTC)[reply]
Okay, I don't know what in the world is going on, since when I posted I could have sworn my response was immediately below and one indent right of yours. Perhaps I made the edit but it returned as session data lost. In any case, if we are going to call the gaits of mice and hopping kangaroos cursorial, then what do we call the gates of long-legged animals like ostriches, horses, and thylacines not adapted to hopping or scurrying? Eucusroriality? I have give an ostensive definition of what I mean, and it doesn't make any sense to call what the bandicoot did in that video (whose posting was helpful, by the way) cursorial in the specialized sense I am looking for. Next I expect the IAU will declare Pluto to be cursorial.... 01:40, 18 November 2015 (UTC)
I think it's fine to say that ostriches and horses run and kangaroos hop, but I'm not that familiar with the study of gaits and skeletal morphology. All I can say is that in many (most?) cases, "cursorial" is used to describe a type of behavior and habit, not a specific gait. I suppose some people have used it to describe a specific gait, but I'm not aware of that usage; I learned the term in a more broad sense of behavioral ecology, not in terms of animal locomotion. Chrissy's links below have a lot of good gait info, but it still looks like there have never been any marsupials that run like deer. Btw, if you have refs that clearly use cursorial to mean a running quadrupedal gait, then maybe we can fix up the article to cover both usages, and then everybody wins :) SemanticMantis (talk) 15:27, 18 November 2015 (UTC)[reply]
"The gaits of 19 species of Macropodinae were studied from 360 m of movie film taken in zoos. Four gaits were identified: (1) the slow progression involving all the limbs plus the tail which was similar in all the species and used mainly while grazing; (2) the walk, the only gait in which the pairs of limbs were not used synchronously and confined to the sole arboreal species of Dendrolagus; (3) the quadrupedal bound involving the use of the hindfeet and then the forefeet in sequence and believed to be a primitive gait because it is only found in the relatively primitive species of Setonix and Dendrolagus; and (4) the bipedal hop, the fastest gait, which is often correlated with the habitat of a species. The probable phylogeny of the Macropodinae is presented, based on gaits and other available taxonomic criteria."[11] Not sure if this helps or hinders.DrChrissy(talk) 20:34, 17 November 2015 (UTC)[reply]
Animal locomotion articles in general I was taught that terms such as "cursorial", "fossorial", "arboreal" mean much the same way I think as User talk:SemanticMantis uses/views them - the terms describe a behaviour or habit. This helps us describe complex situations when a jaguar runs after prey (cursorial) and then drags it up a tree (arboreal). The idea of these terms being related to adaptations is new to me, as of a couple of days ago. However, does the "adaptations" framework not beg the question that every species derived from those first creatures that dragged themselves out of the sea and went on to develop legs and showed "running", is adapted to being cursorial?
This inconsistency in thinking (not pointing at individuals here at all) is very evident on WP. There is no article on Arboreal - it is a redirect to Arboreal '''locomotion'''. Interestingly, it then discusses the arboreal tree snail - does anyone know of any adaptations a tree snail might have compared to a land snail?
Perhaps this discussion should be taken to a project page for wider discussion. - Does anyone have any suggestions?DrChrissy(talk) 16:00, 18 November 2015 (UTC)[reply]
magnet motor
Can make motor spins by magnetic repulsion?
And I saw this on internet. Is it true? — Preceding unsigned comment added by 151.236.160.66 (talk) 15:59, 16 November 2015 (UTC)[reply]
Every electric motor that has ever been built since the beginning of time works by magnetic repulsion. It's not magic or unexpected. It's called "how they work". See the Wikipedia article titled electric motor for all of the details. --Jayron32 16:07, 16 November 2015 (UTC)[reply]
Although if you mean the "free energy" and "perpetual motion" videos you find when you search "magnetic repulsion motor" on youtube, those are all fake. 91.155.193.199 (talk) 18:10, 16 November 2015 (UTC)[reply]
If you mean "is it possible to make a motor spin using only magnetic repulsion/attraction and not using any electrical current" then the answer is "yes you can". However if you think this means you can get "Free Energy" then you will be most disappointed. Just because a magnet can repulse another magnet does not mean it can generate or give you free energy. The repulsion between two magnets can be considered as a form of potential energy. Once this "potential energy" is released (ie, one magnet is pushed away from another magnet), the energy is gone and the repulsion force is diminished. If you want to restore the repulsion force back to its original magnitude, work needs to be done. And work requires external energy. Unless you or some other external entity supplies the energy, the motor will slowly wind down due to friction. 175.45.116.66 (talk) 02:31, 17 November 2015 (UTC)[reply]
If you want "Free Energy" why waste time with hokey pokey magnets when you can let the moon work for you for free. Tidal barrage175.45.116.66 (talk) 02:48, 17 November 2015 (UTC)[reply]
A conventional electric motor uses "magnetic repulsion". Most common electric motors use electromagnetic coils to either attract or repel permanent magnets. So in that sense, the answer is "Yes".
However, there are a very large number of complete nut-jobs 'on the Internet' who totally fail to understand the difference between "force" and "energy". These people are quite utterly convinced that the "force" exerted by a magnet (which essentially lasts forever without running down) is obviously a source of "energy" that lasts forever without running down. And from that key misunderstanding, leap to the conclusion that you really ought to be able to use magnets to make free energy.
Well, no, you can't! Force is not energy. The laws of thermodynamics are among the most well-researched physical laws we have - and they say that getting energy for free is flat out impossible, no matter how clever you are. Sadly, there are whole armies of nut-jobs making things like SMOT and magnetic motors - and most of them are putting up faked videos of these machines working on YouTube. Oddly, none of them are making billions of dollars selling free energy to electricity companies...which is rather telling, I think!
So when we hear "motor spins by magnetic repulsion" - we're 99% sure that it's a nut-job spouting bullshit - and only 1% of our thoughts are that...well, actually, almost all motors work that way - although using copious amounts of electricity to make magnets that can be turned on and off...which is the key to making a magnetic motor that actually works.
If you have access to a source of free energy, is it feasible to store enough of it in a portable battery to cover other costs?--Scicurious (talk) 16:00, 16 November 2015 (UTC)[reply]
Can you be more specific as to the reason for your question? You've just linked to some articles about a coffee chain and one of their products, which confuses what you're asking about and why you are asking. If you could be more direct and give us enough information to answer your question intelligently, that would be helpful. --Jayron32 16:06, 16 November 2015 (UTC)[reply]
I'm not sure that Starbucks would be happy about you recharging large batteries from their electricity supply, even if you were paying for coffee each time. Dbfirs 16:46, 16 November 2015 (UTC)[reply]
Dbfirs, you understood the question right, but this is not about their policies.
More directly: I want to plug a portable battery 2h. What portable battery can I use for this? How much energy would I be able to leech?--Scicurious (talk) 17:37, 16 November 2015 (UTC)[reply]
I've not ever been in a coffee shop where, while drinking their coffee, they ever complained if I plugged in any of my electronic devices (laptop, Ipad, smartphone, etc.) in an available outlet. Many such businesses do expect you to purchase a product to remain and use your device (while consuming said product), otherwise you may be accused of loitering. Of course, YMMV, but if you buy a coffee and sit around in the shop while drinking it, they don't often care if you also plug in your electronics... --Jayron32 17:43, 16 November 2015 (UTC)[reply]
According to [12], a Nissan Leaf can store less than 24 kilowatt-hours in practice. Residential kWh's cost in the high teens of cents [13] - it's cheaper for Starbucks so you can work that out. So my guess is that if you can park your car in the cafe and recharge it in two hours (both probably a no), you can recover the cost of your coffee. Otherwise... probably not. :) Wnt (talk) 17:45, 16 November 2015 (UTC)[reply]
For common outlets there is a max. draw of about 1.5 kw/h at 120 V (and about double for 220 V). You can do the math considering between 10-30 (US)cents/kwh.--TMCk (talk) 18:25, 16 November 2015 (UTC)[reply]
If they are smart, they have a circuit breaker on the circuit(s) that customers use with a relatively low amp limit. Thus, if you attempt to draw lots of electricity, the circuit breaker would flip and you would lose power, along with anyone else on that circuit. The employees might not notice until somebody else trying to use the circuit brings it to their attention. The employees may then look to see who is sucking down all that juice before resetting the circuit breaker. StuRat (talk) 19:39, 16 November 2015 (UTC)[reply]
That doesn't sound all that smart to me. The cost of having a grunt employee throw the breaker and look and apologize is more than the cost of the electricity saved ... and there's a goodwill factor ... and then there's the risk that some uninformed supervisory employee eventually calls up an electrician about the trouble with the circuit, costing vastly more than all the power ever possibly saved. Nay, the less creativity the better where wall outlets are concerned. Wnt (talk) 00:43, 17 November 2015 (UTC)[reply]
Time reversal signal processing
Here is an interesting paper about Time reversal signal processing. Apparently they can recover a numeral "5" from the reflection through a piece of chicken. As Science News put it, "Mosk envisions doctors injecting a dye or other agent to make cancer cells glow inside the body. A mirror would gather up that light, even after it's been scattered by other tissues, and send back a high-energy beam that strikes and sears only the cancer cells." The paper describes recording the reflected light, which is part of it.
But how do you record and replay and amplify a chaotic collection of light in all phases and directions? I don't see how you do this. But I can certainly see applications for the technology, using "quantum dot" sensors, of truly unprecedented creepiness. Wnt (talk) 17:38, 16 November 2015 (UTC)[reply]
Well, this was quite fascinating, although I understood it in the way someone learning multiplication might get the gist of calculus. Hopefully there will be a science documentary on the subject, or there is if someone can post one. μηδείς (talk) 03:41, 18 November 2015 (UTC)[reply]
I don't see how "recording" is necessary for that particular application -- it appears that optical amplification, combined with any of the many kinds of retroreflector, might theoretically be enough for that anti-cancer treatment.
How do you record a chaotic collection of light in all phases and directions? In other words, how do you record a light field? My understanding is that the most common way of doing this is holography.
How do you amplify a chaotic collection of light in all phases and directions? My understanding is that Raman amplification is the most common technique, but amplification can be produced using several other stimulated emission techniques.
This technique seems like it could have a lot of useful applications. --DavidCary (talk) 09:35, 18 November 2015 (UTC)[reply]
Unreasonable Warning?
At one of our local Dollar Stores, I bought a metal cookie baking sheet, described as "Heavyweight steel bakeware".
While taking off the label, my wife noticed the Prop. 65 Warning, and was concerned enough to ask me about it. The text reads "This product contains DEHP, a Phthalate Chemical, Lead and other Chemicals ...)".
Reading the DEHP article, my understanding is that that product is used mostly as a plasticizer, so that doesn't make sense. Now, I suppose that, being made in China, they used a low grade steel containing a high percentage of lead and other bad stuff, but it's also possible that they just use this paragraph as boilerplate on all their products, to avoid problems.
So, two main questions:
1) Is it reasonable that there exists any DEHP in a steel baking sheet?
2) Is it reasonably possible for an unreasonable amount of lead, etc. to be in the sheet?
And a follow-up question (ignoring, for the moment, Wikipedia's dislike of requests for opinions); would you use this as a baking sheet? Bunthorne (talk) 18:50, 16 November 2015 (UTC)[reply]
Is there a label on the product, or is it wrapped in plastic? Would it be possible the label, the plastic wrapping, or the gum used to attach or close any of such contained the chemical? --Jayron32 18:51, 16 November 2015 (UTC)[reply]
There was a label stuck on the product with an adhesive, but it wasn't wrapped in plastic. So it's quite possible that the adhesive contained the DEHP. Bunthorne (talk) 19:10, 16 November 2015 (UTC)[reply]
Steel turns out to be coated in plastic more than you'd think, e.g. tin can. Depending on how "low grade" this is, is it stainless steel? Does it rust? Or does it rely on a coating that may emit chemicals when warmed up in an organic solvent, i.e. when making cookies? Wnt (talk) 18:58, 16 November 2015 (UTC)[reply]
There was no mention of a non-stick coating, so based on that and previous experience with pans of this type, I'm sure it will rust, given a chance. Bunthorne (talk) 19:10, 16 November 2015 (UTC)[reply]
I would line the "bakeware" with aluminum foil or parchment paper before using it, to offer some protection from contamination. You might also want to run it through the oven without any food a few times, to burn off or outgas as many chemicals as possible. I'd do this in summer, with the windows open. StuRat (talk) 19:44, 16 November 2015 (UTC)[reply]
It's also worth noting that the Prop 65 warning labels have no penalty for being there without need. My guess is that it's put there to cover unforeseen legal accusations toward the company that made/distributed/imported them. FrameDrag (talk) 20:35, 16 November 2015 (UTC)[reply]
My guess is that the steel does indeed have a thin coating of plastic, designed to keep it from rusting until after you buy it, use it once (burning off the plastic coating), and then find a rusted piece of junk after you soak it in the sink. If this is the case, then you might be able to save it by coating it in oil after each use and immediate cleaning, like a cast iron pan. StuRat (talk) 20:40, 16 November 2015 (UTC)[reply]
Is contamination of food with rust really a health issue? 129.215.47.59 (talk) 11:37, 17 November 2015 (UTC)[reply]
Not a health issue, unless the chunks of rust are big enough to cut you, but rusty food is quite unpalatable. StuRat (talk) 02:50, 18 November 2015 (UTC)[reply]
I doubt this. Burning plastic can start fires, gives off noxious fumes, and would react with whatever you were baking to make it unpalatable. Unless this is a product that was just introduced, I'm pretty sure people would have noticed this and made a big deal. Also, purely from a cost standpoint, plastic costs money, and applying plastic coatings costs even more (you need machines, special plastics, etc.). I think it's unlikely doing such a thing would be cost-effective, especially when the product is being sold at such a low price (as it was from a dollar store). --71.119.131.184 (talk) 13:13, 17 November 2015 (UTC)[reply]
Many items end up in dollar stores because they were slated for regular retail stores but deemed to be defective in some way, such as the way I described. StuRat (talk) 02:50, 18 November 2015 (UTC)[reply]
I think FrameDrag is right. I live in California, so I'm familiar with the effects of Prop 65. It was well-intentioned, but it's a case study in unintended consequences. Any potentially harmful chemical has to be reported, regardless of whether the levels present are actually meaningful, so most places just slap warnings on everything that might remotely fall under the law to avoid legal consequences. In return, people don't pay any attention to the notices, because they're usually irrelevant. Notably, in the past few years I've noticed numerous online stores slapping Prop 65 warnings on all kinds of things. For example, here's what Amazon.com puts Prop 65 warnings on, which includes fruit, nuts, and vegetables. So I would probably just ignore the warning. --71.119.131.184 (talk) 13:13, 17 November 2015 (UTC)[reply]
The notice might be referring to listed substances contained in the label. Thincat (talk) 12:41, 17 November 2015 (UTC)[reply]
Before this is transfered to Commons, it would be appreciated if someone could determine it's species. (This is so it can be put in the right taxonomic categories on Commons).
Sfan00 IMG (talk) 23:20, 16 November 2015 (UTC)[reply]
Neuroscience: Is my "Sympathetic fight response" axis accurate?
Peripheral sensory cell > Preganglionic cell > Dorsal root ganglia cell in the Sympathetic chain > Ventral root ganglia cell in the sympathetic chain > Post-ganglionic cell that activates an organ such as the pancreas (or a muscle).
Was I accurate? I ask this after feeling that some books\people tend to confuse the details of this axis... :|
Perhaps the questioner is thinking of the abdominal swelling seen in severely malnourished children. See here for some explanations. AndrewWTaylor (talk) 11:37, 17 November 2015 (UTC)[reply]
Gorse brush prickles cause a rash but what is the active agent?
What about gorse bush prickles causes an inflammatory response? Getting prickled by gorse bushes causes an inflammatory response so the pricks appear as red spots which persist a couple of days following exposure. A friend said it was "phenolic compounds" but I can't find anything about it online. --129.215.47.59 (talk) 11:34, 17 November 2015 (UTC)[reply]
Yes, the Daily Mail headline suffers from the post hoc ergo propter hoc fallacy: She was killed after the scratch, by something unrelated to the nature of the cause of the scratch. --Jayron32 23:42, 18 November 2015 (UTC)[reply]
November 18
Using the 9 kcal of energy per 1 gram of fat figure to calculate weight loss
I see many sites, including Wikipedia, explain macro-nutrients and dieting like this (loosely and poorly paraphrased):
Proteins and carbohydrates contain 4 kcal per gram, and fats contain 9 kcal per gram. Thus your daily total energy intake is (proteins[g] + carbohydrates[g]) * 4 kcal/g + fat[g] * 9 kcal/g.
If you consume more food energy than you use, you gain weight. If you consume less food energy than you use, you lose weight.
Which makes a lot of sense to me.
I'm wondering whether the "9 kcal of energy per 1 gram of fat" figure can be also used to calculate the amount of weight loss (or gain) as well. Suppose someone is achieving a consistent a 90 kcal energy deficit per day for a long period of time. Does that mean they will be consistently, averaged over a long term, losing 10 grams of fat per day? Assuming the person lives a sedentary lifestyle and thus has no muscle gains or losses. 731Butai (talk) 06:29, 18 November 2015 (UTC)[reply]
I don't believe it's reversible like that, no. Also, while this would be true: "If somebody reduces caloric intake in one way without increasing it in any other way while still burning the same amount of calories, then they should either lose weight or at least gain weight more slowly". Unfortunately, in the real world, it's not as simple as that. When they eat fewer calories their body notices and torques up hunger to get them to consume the usual amount. And/or it may decrease the basal metabolic rate (they may feel colder) and the lack of energy may make them more sedentary than they were previously. One notable example of all this is that when people switch from regular soda to diet soda, which contains fewer calories, they do not lose weight. StuRat (talk) 06:59, 18 November 2015 (UTC)[reply]
(2 edit conflicts.)(I slightly reformatted your question for readabiltiy reasons.) StuRat you are not wrong, but s/he says "consistent a 90 kcal energy deficit per day" which undercuts your exceptions. The answer is yes, with possible complications. There are more ways to store energy, for instance glycogen, which is short term storage of linked glucose, 4kcal/g. This is used first, it is more readily available. But it is the first to be replenished. So deficit has to go somewhere, and assuming full grown adult and no other tissue or muscle losses, and averaged over a long time, so answer is yes. You can also estimate volume change if you look up density of fat (a little less that water). Phun Phact: A gallon of gasoline has 33.7kWh = 28976. kcal. If that were fat it would have mass of 3.2 kilograms= 7 pounds. Takes a LOT of work to get rid of it. GangofOne (talk) 07:14, 18 November 2015 (UTC)[reply]
The basic arithmetic and chemistry works - but the underlying assumption that energy consumption doesn't change is the 'gotcha'. If you live in a cold climate - and have a perfectly balanced diet, so you're neither gaining nor losing weight - then buying a better jacket can cause you to put on weight. You're using less calories to maintain body temperature - so you need fewer calories than you did before.
The claim is that the body "goes into starvation mode" when you eat less, and that this can defeat your efforts at dieting...and that when you stop dieting while "in starvation mode", you'll pack on the pounds very rapidly.
This seems superfically plausible - but the problem with this claim is that (although I've searched and asked this question all over the place) I can find no concrete evidence for it. Clearly there is some kind of effect - but nobody seems to know how much calorie deficit causes the "switch" to turn on - or for how long you can go on a deficit diet before it turns on - or how strong the effect is - or for how long it remains on after your diet returns to normal. It's astounding that roughly 50% of all dietary advice repeats this "information" - but nobody seems to have any kind of solid research evidence to back it up. Since (if true) it's a critical piece of information for all diets - this is horrifying.
Some diet guides tell you to come off your diet periodically (say once a month) in order to 'reset' the starvation mode thing - suggesting that the "starvation mode" thing operates over a scale of weeks. Other people tell you it's vital to eat a good breakfast in order to avoid flipping your body into starvation mode before lunchtime - suggesting that "starvation mode' happens over a matter of hours. This is bullshit "cargo-cult science". Without solid experimental facts, the best guess is that the body has evolved to operate efficiently at all times - and that if "starvation mode" existed, we'd notice serious deficits in performance. I've actually tried to see this happen in myself...switching back and forth between regular soda and sugar in my coffee to diet soda and artificial sweetener - or going onto a 1000 calorie "juice-only" diet. Neither of those things cause me any mental impairment (beyond the occasional craving for a Sonic #4 meal with extra tater tots and a medium chocolate shake), there is no measurable drop in my body temperature or any obvious lack of performance of any kind...and my rate of wait loss is pretty much as predicted by the calorie restriction. Now, I might be a weird outlier - but tell me how this supposed "starvation mode" is saving energy? Is my hair growing more slowly? What precisely is being eliminated to save all that energy?
Yet, this claim for "starvation mode" is repeated everywhere - and with random claims for how long it takes to go away, how much it takes to trigger it and what percentage or calorie-count difference it makes to energy consumption.
The diet industry is worth billions - why no solid research findings?
That said - if anyone knows of a decent empirical study that answers those questions...I'd love to hear about it.
Bottom line - you need to eat fewer calories to lose weight - the difference between the various diet tricks are all to do with how well you can stick to them - and that's down to glycemic index - how long you can go with less food and not feel so insanely hungry - bottom line of which appears to be to eat relatively indigestible foods that stay in your system for longer. SteveBaker (talk) 15:54, 18 November 2015 (UTC)[reply]
Steve, have you read the empirical study cited at Starvation_response#Magnitude_and_composition? It discusses how the energy is saved, and that info is also summarized in our article section. Ref [6] there also looks interesting. I'm sure there are more empirical studies, but those were the easiest to find. At a glance, this study [15] cites a lot of empirical research on human starvation response, and might be a good way to get more sources that cover your interests more specifically. Here's [16] a whole article in the prestigious Annual Reviews series summarizing what was known in 2006 about the physiological responses to food deprivation. There's also a lot of mechanistic studies that show what factors mediate things like macroautophagy, like this one [17]. Look, this is complicated and subtle stuff, but please don't call it cargo cult science. Just because some sources play fast and loose with claims and implications does not mean that there is not serious, peer-reviewed empirical science available on the topic. SemanticMantis (talk) 17:54, 18 November 2015 (UTC)[reply]
The studies that you cited above refer to extreme starvation - complete food derivation and were actually about animals. I doubt that there are serious studies of humans under conditions of moderate food deprivation as is often the case in diets. I also doubt that a moderate food deprivation induces changes so significant to seriously slow weight loss. Ruslik_Zero 19:46, 18 November 2015 (UTC)[reply]
I have read Starvation_response#Magnitude_and_composition (did you?). It starts off by talking about a on-off study done on just 8 people who'd been cut off from the world in the ill-fated Biosphere2 experiment. Aside from the fact that this is vastly too small of a sample to draw any conclusions whatever - these people were initially selected for the Biosphere2 experiment based on all sorts of criteria that separate them out from "average" humans. The effects they noted explain calorie requirement reductions that amount to about 180 calories/day...which is not much of a drop from normal - just what you'd get by replacing one and a half cans of soda per day with diet soda - and certainly not enough to prevent a modestly aggressive calorie reduction diet plan from working! They describe about a third of those savings as "statistically insignificant"...and with all of the other horrible things that happened to those 8 people during their weird "experiment", I could believe they were screwed up in so many other ways as to make any conclusions utterly invalid...so meh...not "cargo cult science" - it's "very, very bad science" and with conclusions that have zero bearing on the question at hand here.
As for the remainder of that section, it discusses in mind-numbing detail how a TOTAL fast (zero calories) causes various energy stores in the body to keep the body running normally. This is not what people are talking about when they claim that the body might flip into a mode where it DOESN'T burn much fat when calories are somewhat restricted by somehow turning on a more efficient energy consumption switch. Quite the opposite in fact - it's saying that if you eat less, your fat reserves get used up in trying to continue to power the brain...which is precisely what you'd hope your diet would do for you! Far from making me think that this supposed effect is "real" and well studied - it makes me believe the complete opposite! Our bodies will work to consume all of our fat reserves and then switch to consuming our muscles and other proteins in a concerted effort to maintain the usual amounts of energy production despite low to zero calorie intake.
OK - so having dismissed what our article has to say...what about [18]? Well, this study was about the effects of Human Growth Hormone on starving (ie ZERO calorie intake) obese people - so the test group getting HGH supplements aren't telling us anything of value because we're not going to be doing that while dieting. The control group lost a heck of a lot of weight - there are descriptions of how and why - but no indication of the things that matter for people on a diet (How many calories can I cut without turning on "starvation mode"? How much energy will my body save when going into this supposed more-efficient-metabolic state? How quickly will that effect rebound? ...and so on). That article in no way addresses the questions that need to be answered on this matter. Also, it's talking about complete starvation for weeks! This is not a scenario we care about. I want to know what happens when I do a "sensible diet" and go from (say) 2,500 calories per day to 1,500 per day - and I'm not taking any HGH!
How about your third reference [19]? Well, it *might* be useful - but it's behind a pay-wall and the abstract doesn't look promising. It doesn't mention humans at all (although "animals") - and we know that the human body responds differently from other mammals in terms of how our brains keep functioning during periods of starvation - we specifically DON'T shut down brain functions when food is in short supply - and there is biochemistry in your first and second sources to back that up. What the abstract says is that during periods of starvation, "animals" (unspecified) lower "spontaneous activity" and body temperature. Well, I know that during a 10 day "juice-only" 800cal diet that I did, my body temp didn't fluctuate at all (I was tracking it every day for a different reason). I still went to work and did all the things I usually do in evenings and weekends...I lost 10lbs...but I don't think a "starvation mode" switch was flipped at all (although - I definitely felt pretty amazingly hungry the entire time). But STILL - I see no data about how little I can eat without turning on this supposed switch - or what the effect of flipping the switch is on energy requirements - or how rapidly it turns back on again. NOTHING.
Then we have [20] - which is frankly incomprehensible to the layman...which is OK - but it doesn't mention anything about how little calorie intake is required to trigger these changes - or (AFAICT) how much these cryptic changes reduce energy needs within the body. Maybe you could summarize the results for me - but I suspect the article has no bearing on the question at hand since it only seems to discuss mechanisms at the cellular level and not whole-body responses.
So again...tell me where I can find the answers to the following three questions:
How few calories can I eat without triggering this response?
Having triggered the response, how many fewer calories will my body consume?
How long after providing more calories than the answer to question (1) will my body return to non-starvation mode?
Those three questions are critical to either supporting the notion that modest amounts of dieting doesn't work - or debunking that idea.
Until we know that - anyone who trots out the old argument that if you cut your calorie intake, you won't lose weight because of this mysterious "more efficient metabolism" is indeed indulging in cargo-cult science...and that includes nearly every contributor to every discussion we have on this subject here on the Ref Desk. Show me the references!!
Look, I'm not going to try to support your "old argument that..." claim, because it's obviously not true. Also, I'll note that the Annual Review ref has lots refs and results for humans - we are animals too, and you can ask at WP:REX if you'd like a copy. Your skepticism of the existence of the starvation response is... puzzling, and I'd like to give more general refs that support the claim that "type and amount of caloric intake can alter human energy budget, including baseline metabolic rate, as well as amount and type of weight lost. Additionally, humans can specifically alter their energy budgets to use less energy when undergoing some level of caloric deficit for sustained periods." This doesn't rest just one paper, there are many, just use google scholar to find more. After some more searching, I found a freely accessible article specifically about metabolic changes in humans on different weight loss diets of 1,200 and 800kcal, with and without ketogenic diets, and also with starvation [21]. Patients' base metabolic rate changed by a maximum of -18.9%. So doubt all you want, but my reading of this article is that it shows good evidence that in human subjects caloric restriction can alter the base metabolic rate and total energy balance, e.g. a "starvation mode" that is real and empirically supported, and can occur in realistic weight loss diet plans. Here's another study that looks at the effects on baseline metabolism due to 24 weeks on a "semistarvation" diet of about 1600 kcal [22]. Figure 1 there shows how many less calories were burned, and your questions about how much restriction and for how long are answered for at least this one case - 1600kcal and 24 weeks, note also the results on the recover phase. There's still a lot more work to be done of course, e.g. it would be nice to have a fully factorial kcal/time design, but I don't think that's likely to exist. But I will no longer argue with you about whether or not the human starvation response is "cargo cult" science. The effect is almost certainly real, despite the fact that you don't think that your 10 day juice diet changed your BMR. I don't know or care anything about weight loss, and make no claims about it. My primary intent here is to give scientific refs that quantify the starvation response in empirical studies of human subjects. SemanticMantis (talk) 20:46, 18 November 2015 (UTC)[reply]
I know from personal experience that eating little you can lose roughly half a pound a day for long periods, though it's not all fat of course. My feeling is that "to an order of magnitude" this is correct, bearing in mind that changes in fluid volume both intracellularly and extracellularly can easily overwhelm the fat-based effect. Wnt (talk) 16:03, 18 November 2015 (UTC)[reply]
Chimerism in criminal evidence
It seems that ruling people out solely based on DNA evidence could exonerate guilty parties who exhibit chimerism. Unless a rape suspect, for example, is tested for sperms, which I find unlikely, they could be set free if there is no other evidence. How big of a problem is this? 69.22.242.15 (talk) 14:19, 18 November 2015 (UTC)[reply]
Our Chimera (genetics) article doesn't explain this, but there is growing evidence that people do sometimes (perhaps often, perhaps always) carry around some DNA from their mothers, and that mothers sometimes collect DNA from their unborn children (see THIS for example). So...to be sure that DNA obtained from (say) a blood test would correctly match (or not match) sperm in a rape case - or something of that nature, is indeed, theoretically, problematic. Since this is a relatively new discovery, I think it's too early to guess how much of a problem this is. However, the chimeric DNA will always be from the person's mother, child (if female) or weirdly unborn twin - so the DNA from one part of the body will always have half of the genetic information that the DNA harvested from elsewhere would contain. So it should be relatively easy to fix the problem once it's better understood. My gut feel is that it would be exceedingly rare for this to change the outcome of a legal case though. In the specific example you propose, a man who had committed rape couldn't have sperm cells from his mother, or his child - so it would have to be the "weirdly unborn twin" thing - the twin in question would have to be fraternal, not identical, and would also have to be male...and the testes cells would have to have come from the twin - and not (say) the heart or the brain or some other place where blood cells are not made. The error could only be in the wrongful dismissal of the case - not a wrongful conviction. It would also have to be a case where DNA was the only factor in the dismissal - in the teeth of eye witnesses and other DNA sources such as hair and skin. This narrows the odds considerably...so I'd say that the odds of a wrongful dismissal ever having happened as a result of this would be very slim indeed. But until we have better information about the incidence, all bets are off. SteveBaker (talk) 15:03, 18 November 2015 (UTC)[reply]
Lydia_Fairchild is a good example of legal issues surrounding chimerism, but not a criminal case. This [23] paper on the topic of legal issues and human chimeras. It seems to be written by a law student and not peer-reviewed, but it does have many additional refs. SemanticMantis (talk) 15:33, 18 November 2015 (UTC)[reply]
Since User:Medeis took it on himself to remove my comment, I'll repost it with all good cheer replaced by typical Wikipedia defensive humorlessness.
No country assumes its court will catch every single perpetrator, so these rare differences seem like a trivial issue. The sampling of fetal DNA from the mothers is far more interesting. An example of a situation where such a technique could have been applied followed an abortion by Monica Lewinsky.[24] Had right-wing opponents of Clinton been aware of the technique, which existed even then, they might have tried to get a warrant to look for Y-DNA from the father in Lewinsky's blood in the hope of contradicting Clinton's testimony; indeed, they could technically attempt it even now, given the right legal pretext. Wnt (talk) 01:33, 19 November 2015 (UTC)[reply]
Wormholes and entanglement
There have been previous discussions on wormholes, e.g. Wikipedia:Reference desk/Archives/Science/2010 July 2, but this article is certainly interesting. It says there is a hypothesis that quantum entanglement is the basis of gravity, and indeed, that "ER = EPR", i.e. that the entanglement of two particles is equivalent to the formation of a wormhole! But there are some things I don't really get.
To begin with, there's the matter of multiple entanglement. I had thought I had read of cases of multiple particles being entangled, which is in no way like the geometry of an EPR bridge; but apparently there is a strong restriction in favor of "monogamy of entanglement". This concept is discussed somewhere around 20-30 minutes into a lecture here cited by the article above. Our article on quantum entanglement doesn't use the term; Susskind specifies that it is monogamy of maximal entanglement.
Monogamy is used in an example by Susskind about 38 minutes in... the problem is that it seems moronic to me. Note I am aware that as he is the quantum physicist and I am definitely not, this implies some principle of relativity at work! The idea of the "AMPS paradox" he describes is that any small patch of space may be entangled with a small patch of space nearby; yet a small patch of space just inside the event horizon of an "entangled black hole" cannot be entangled with a patch just outside it. The problem I'm having is, his patches of space A and B look to me like they were sitting there before he dumped N buckets of entangled matter into the area to make it a black hole, and their affections should therefore not be part of the black hole's entanglement. Indeed, how could anything dumped into a black hole linger just beneath the event horizon? Yet this seems to be the whole basis in that lecture for introducing the idea that the entanglement extends to a macroscopic wormhole.
Another issue is the "tensor network" - is this some kind of super entanglement? The graphic in the Nature article shows entangled pairs as being the outer edges of some kind of graph. While each pair is linked, it looks like each entanglement is linked to some other.
More basically, is this implying that every particle must be entangled with some other, and we just might not know which?
And as for space... Susskind draws a line down the blackboard, says this patch on the left will be entangled with this one on the right (i.e. if there's a virtual particle here there must be one there). I assume because of monogamy, that's a simplification, since each can only be entangled with one other which might be in any direction??
Then there's my main confusion with wormholes. The one thing I think I know about black holes is that when you fall in one you go down. Yet a traversible wormhole seems to be based on the notion that you can go back and forth! And the other thing I think I know is that you don't come back out... yet here they show black holes compared to entangled particle pairs where the kind of test done on one is somehow communicated to the other. On the plus side, 'monogamy' is consistent with the EPR bridge being between just two worlds. In the earliest days people imagined the target as a white hole; now it's seen as a black hole that emits Hawking radiation... it leads me to vain speculations.
Anyway, can people tell me something about this, or better still, write about half a dozen articles about these new concepts: monogamy (physics), AMPS paradox, the tensor network (whatever it is), ER = EPR etc.? Thanks! Wnt (talk) 15:34, 18 November 2015 (UTC)[reply]
I don't understand entanglement monogamy, but presumably it means there are no systems of 3+ particles that are analogous to a Bell pair, which is a maximally entangled 2-particle system. There are nonclassically entangled systems of 3+ particles, such as the |000〉+|111〉 state used in the GHZ experiment, but they are in some sense not maximally entangled. The article Concurrence (quantum computing) says it means "the concurrence of a qubit with the rest of the system cannot ever exceed the sum of the concurrences of qubit pairs which it is part of."
A crucial part of what Susskind talks about, that he never mentioned by name in the part of the video I watched, is black hole complementarity. This is what he's talking about when he says that A and B' are the same thing (at around 45:00).
File:PENROSE2.PNGThe wormholes here (Einstein–Rosen bridges) are not traversable. It would be bad (causality-violating) if they were traversable. The causal diagram (Penrose diagram) that Susskind draws on the board at around 50:30 is the upper left diagram in the image on the right. The wormhole "throat" he draws is a horizontal slice through the center of that diagram, with the circle at the middle of the throat being the middle point of the diagram. Because it's a horizontal (hence spacelike) slice, you can't have a worldline lying in the slice, so you can't go through the wormhole he drew. As shown in the Penrose diagram, no timelike or lightlike worldline can pass through both exterior regions, but worldlines from the two exterior regions can meet in the shared future interior region. In other words, if you make a Bell pair of black holes, and toss Alice into one and Bob into the other, they may meet and exchange information inside, but no one who stays outside the first (resp. second) black hole can learn anything about Bob (resp. Alice).
It's not clear to me if this is supposed to be related to the nonclassicality of entanglement. I doubt Susskind would argue that violation of Bell's inequality is due to some sort of communication through the wormhole, because you can't use entanglement for nonlocal communication, and Susskind (like Einstein) is the kind of person who believes that sort of thing isn't true by accident. No possibility of a FTL radio means fundamentally no communication going on. But he might think that violation of Bell's inequality is somehow necessary for wormholes to make sense, even if we don't understand how yet. -- BenRG (talk) 01:18, 19 November 2015 (UTC)[reply]
what defines a thila, the marine biome with instances found in the Maldives?
There is no current article on this topic on Wikipedia and the information elsewhere online appears poor. It seems a thila is basically a submerged island close to the surface that supports reef and other marine habitats, but it isn't clear what actually defines a thila and how it differs from other similar marine environments. It would also be nice to know how they form geologically. Are they volcanoes that have not yet breached the surface? Old volcanoes that have eroded to below the surface, some other geological formation? If they are volcanic how do they differ from atolls?
Thanks for any additional details you can provide on the topic.
166.176.187.231 (talk) 17:30, 18 November 2015 (UTC)[reply]
Thila is a Maldivean name for a small coral reef within the lagoonal part of an atoll, so just a local high point, pinnacle reef or patch reef are possible equivalent terms[25]. Mikenorton (talk) 21:21, 18 November 2015 (UTC)[reply]
This says what several ancient Mayan statues show, that indeed Maya had unusually large eyelids due to extra fold which gave them lazy look. What's the evolutionary or physiological reason behind that?--Brandmeistertalk 19:03, 18 November 2015 (UTC)[reply]
Just as a counterargument: how sure are you that the statues are supposed to be scrupulously accurate? I can pull artwork from a hundred other cultures where the art does not look like a photorealistic picture of the people in question. For the record, there are still seven million Mayan people still walking the earth. If you want to know what they look like, you can just, you know, look at them. We have photographs. --Jayron32 19:09, 18 November 2015 (UTC)[reply]
I don't know about these, but I recall it turned out that after many years of being perceived as simply white marble, Roman statues were found to have actually been painted with brilliant colors that had since worn away. The appearance of the eyes of any statue, therefore, needs to be considered skeptically since someone might have adorned the stone with material that is no longer present. Wnt (talk) 19:32, 18 November 2015 (UTC)[reply]
I looked at the references for the article you cited, and they don't appear to support the statements it makes about the Mayan appearance. I can't find any other scholarly source that supports them either. Possibly they're just obscure, but a measure of skepticism might be appropriate. Looie496 (talk) 20:22, 18 November 2015 (UTC)[reply]
Then what it's all about? If you look at multiple Mayan statues (including that of K'inich Janaab' Pakal), large eyelids are quite noticeable and it's not an individual feature. A local stylistic embellishment? Brandmeistertalk
