Wikipedia:Reference desk/Archives/Science/2016 May 24
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May 24
[edit]Cellulite in other species
[edit]Is cellulite present in species other than humans? Munci (talk) 02:48, 24 May 2016 (UTC)
- [1] is all I can find. --Jayron32 02:53, 24 May 2016 (UTC)
- Humans have rather thin skin, little or no fur, often live past the fertility age, and don't always exercise to stay fit (don't rely on running away from predators and/or chasing prey). All these factors combined make cellulite more apparent. --Dr Dima (talk) 16:47, 24 May 2016 (UTC)
Elephant skulls
[edit]Imagine an expert who had never seen or heard of an elephant before. To what extent could this expert deduce the presence of the elephant's trunk just by looking at the skull? Presumably, there would be some evidence in terms of attachment points for muscles that wouldn't make sense without a trunk. But could an expert tell much about what type of non-bone-containing appendage had been present in the living animal? And are there any fossils of large extinct animals (megafauna, dinosaurs, etc.) for which experts can predict large appendages that have no remaining fossilized parts like an elephant's trunk? Edgeweyes (talk) 17:54, 24 May 2016 (UTC)
- An interesting question. Perhaps research on the history of the discovery and description of mammoths might help. I believe some have been found in very good condition (not fossilised) in ice (confirming the trunk), but were fossilised forms found before that, and if so, what did the scientists at the time think? DrChrissy (talk) 18:02, 24 May 2016 (UTC)
- Their similarity to modern elephants would suggest that they also had a trunk. StuRat (talk) 18:05, 24 May 2016 (UTC)
- See indricotheriinae. Late indricotheres (see Paraceratherium) are suspected to have possessed a prehensile trunk or upper lip, judging by their fossilized skulls. However, no soft tissue traces have been found so far to either validate or invalidate this hypothesis, AFAIK. --Dr Dima (talk) 19:12, 24 May 2016 (UTC)
- They'd've known the animal had a prehensile snout, given the muscle attachment points. We know, for example, that many bird-hipped dinosaurs had cheeks (unlike crocs and T. rex) for just the same reason. I highly doubt they would have expected its size and versatility, which is unparalleled. μηδείς (talk) 20:38, 24 May 2016 (UTC)
- Completely parenthetical to the main point, but T. rexes may well have had cheeks and lips Source. In this case, it was only proposed by comparison to modern animals rather than specific clues left in the fossilized remains. Matt Deres (talk) 00:01, 25 May 2016 (UTC)
- Oh, great, dreams of T. rex kisses. μηδείς (talk) 02:12, 25 May 2016 (UTC)
- What's the alternative to having cheeks and lips, just a bare skull ? :-) I believe the question is to what extent those lips covered the teeth. StuRat (talk) 15:38, 25 May 2016 (UTC)
- Think of a crocodile Stu, or a snake. They do not have cheeks, flaps of skin that hold food in the mouth, or lips, to manipulate food at the front of the mouth. (You are using the word cheek non-technically in your question about the side of the head, not in the technical way meant by comparative physiologists.) Crocodiles don't chew, they simply gulp. If humans were like crocs, when we opened our mouths you could see our molars from the side. Rather, unless we pull back our cheeks, normally only our incisors and maybe our canines are visible. That some dinosaurs like hadrosaurs had cheeks and muscles with which to chew was only recognized recently. See http://bio.sunyorange.edu/updated2/pl%20new/39%20Ornithischia.htm μηδείς (talk) 18:28, 27 May 2016 (UTC)
- Of perhaps tangential interest, here's a very nice gallery of artwork from the middle ages, showing depictions of elephants made by people who'd never seen one. SemanticMantis (talk) 21:06, 24 May 2016 (UTC)
- Wow, just when I thought medieval art couldn't get any worse. We need to send some kindergartners back in time to then, so they can stun the art world with their relative skill. StuRat (talk) 00:42, 25 May 2016 (UTC)
- It is widely (and perhaps even accurately) held that finding such skulls was the source of the Greek Cyclops myths. Andy Dingley (talk) 00:14, 25 May 2016 (UTC)
- Why would that be ? Elephant skulls clearly have two eye sockets, not one. StuRat (talk) 01:25, 25 May 2016 (UTC)
- Take a look at the picture attached.--Dr Dima (talk) 02:32, 25 May 2016 (UTC)
- @Andy Dingley: Maybe, but Greek physicians were very fond of white hellebore as a purgative, which contains cyclopamine. I bet that, at least, they saw the baby cyclopes as evidence that the mothers had been mistreated. And who knows? Maybe some kid beat the odds and survived holoprosencephaly to adulthood. I bet if you saw baby cyclopes and saw bones of giant cyclopes and maybe even heard of a cyclops touring with some ancient Greek freakshow, you'd start believing in them. :) On a related topic, see sirenomelia. Wnt (talk) 21:55, 25 May 2016 (UTC)
- Northern Europe has a mythology of cyclops, cynocephali, blemmyes and monopods, all around the borders of every map. But the Greek cyclops were also giants. Andy Dingley (talk) 22:33, 25 May 2016 (UTC)
- @Andy Dingley: Maybe, but Greek physicians were very fond of white hellebore as a purgative, which contains cyclopamine. I bet that, at least, they saw the baby cyclopes as evidence that the mothers had been mistreated. And who knows? Maybe some kid beat the odds and survived holoprosencephaly to adulthood. I bet if you saw baby cyclopes and saw bones of giant cyclopes and maybe even heard of a cyclops touring with some ancient Greek freakshow, you'd start believing in them. :) On a related topic, see sirenomelia. Wnt (talk) 21:55, 25 May 2016 (UTC)
Concorde's yellowish exhaust
[edit]On this and other videos Concorde's exhaust jets are yellowish or of mud color. I haven't seen such tinted exhaust gases on other modern aircraft like Airbus or Boeing. Why is that?--93.174.25.12 (talk) 18:17, 24 May 2016 (UTC)
- My first thought: NOx. It comes from the specifics of Concorde's engines and its extremely high fuel consumption during take-off. Note that the yellowish exhaust gases appear not immediately when it throttles up for take-off, but when it engages the afterburners. PiusImpavidus (talk) 18:55, 24 May 2016 (UTC)
- We should probably explain why a supersonic plane has an extremely high fuel consumption during take-off. An airplane can either be optimized for efficiency in subsonic flight or supersonic flight, but not both. For regular airplanes, they are optimized for subsonic flight, and always fly in that range. For supersonic planes, they have to choose one or the other (or a compromise that really isn't very good at either). So, in the case of the Concorde, they chose to optimize it for supersonic flight, meaning it is highly inefficient at subsonic speeds. This is one reason why the ticket prices were so high and why supersonic commercial flights never really "took off" (the fatal accident was the last nail in the coffin). StuRat (talk) 20:50, 24 May 2016 (UTC)
- Tu-144 at 11:00 also appears to have the same yellowish exhaust on takeoff.--93.174.25.12 (talk) 21:45, 24 May 2016 (UTC)
- Couldn’t see the 'yellow' the first time around but there again I'm used to viewing old footage so my eyes were automatically compensating for the fact that these where shot on film and the dyes have drifted -as they do. Here is some extreme examples of older footage before and after colour correction. [2] . It is normal coloured smoke that 'now' appears yellow on the film.--Aspro (talk) 02:59, 25 May 2016 (UTC)
- There are several mentions of Concorde's "yellow exhaust" in online forums and blogs, (eg "the familiar droop-winged bird began creating that plume of yellow exhaust,") but no explanation that I could see. Alansplodge (talk) 08:41, 25 May 2016 (UTC)
Vitamin decay?
[edit]Do microwaving, cooking, or time deteriorate the vitamins in food? Would orange juice have less vitamins some hours after being pressed? --Llaanngg (talk) 21:58, 24 May 2016 (UTC)
- this articel here in german says, Vitamins don't get destroyed by microwaving and they will be left as much as like you had cooked or grilled your food, because while cooking the vitamins may get lost. http://www.spiegel.de/gesundheit/ernaehrung/mythos-oder-medizin-zerstoert-die-mikrowelle-vitamine-a-961783.html For your other question i have also made my research in german, i came to this site http://www.gutefrage.net/frage/stimmt-es-dass-frischgepresster-orangensaft-sein-vitamin-c-verliert-wenn-man-ihn-zu-lange-stehen-l and on this site it is said, that you have to drink a fresh orange juice immediately, the vitamin C gets lost when the drink gets up to room temperature and if it sees sunlight after 5 hours you will have lost up to 70% of the vitamin C. If you put it into the freezer, you would have lost only 20% after 5 hours. --Ip80.123 (talk) 22:15, 24 May 2016 (UTC)
- The 2nd German source looks like a forum. I was searching for some primary research on the topic. All information that I get seems to be just someone expressing his opinion. Llaanngg (talk) 22:29, 24 May 2016 (UTC)
- Some nutrients are diminished due to heat, but it shouldn't matter whether the heat comes from a traditional oven or a microwave oven. StuRat (talk) 00:34, 25 May 2016 (UTC)
I don't understand why your article in english about Trace element is so short. In german it is way bigger. And the Elements are all listed there. But talking about the Elements, I got a question. The Elements in the German wikipedia de:Spurenelement are listed as necessary for the human body, because there were seen deficiency symptoms if a person has to low of one of this Elements.
But I don't understand, why there is listed "fluoride". The other article in German de:Fluoridierung especially says, that there was never seen something like "Fluoridmangel" or "Mangelerscheinungen wegen zu wenig Fluor" which means, a deficiency symptoms because of not having enough fluoride, could never be saw and are absolutely unknown. Even if there was any of deficiency symptoms because of this, no one of them were influencing the body health in any way, and not as hard, as the other Elements which are listed in the list. (they cause really serious health problems if a body don't get enough of them). So this just feel not right, that fluoride is listed as a Trace element, if deficiency symptoms are unknown - but fluoride poisoning is a serious problem, why there have been lot of dead children which have eaten 2 tubes of toothpaste. Any Idea why this German wikipedia need to have so much inconsistencies and ambiguities? --Ip80.123 (talk) 22:01, 24 May 2016 (UTC)
- In EN wikipedia, as you notidced, trace element is more of a disambiguation "stub" page, because the term 'trace element' has several meanings. The full article for trace elements related specifically to diet is linked to our article called Dietary element. In that article it actually explains WHY fluoride is listed in the section called Other elements. As to why the German article is inconsistent, the correct place to raise that concern would be on the article's talk page. Vespine (talk) 22:50, 24 May 2016 (UTC)
- I'm not sure that the onus is on the German wikipedia, since our inclusion of fluorine as "essential" is decidedly idiosyncratic. -Nunh-huh 06:56, 26 May 2016 (UTC)
- But I'm mot sure the relevance of what your saying to the fact that two different German articles contradict themselves. The German wikipedia should be following their own standards of sourcing etc. Whatever problems may or may not exist in our articles, the onus is obviously on them fix problems which exist on their wikipedia, like a contradiction between two different German wikipedia articles. I'm not sure if there is even a contradiction anyway, the OP may simply be mistaken. If the OP believes there are problems with the listing of flouride in the German wikipedia article regardless of a contradiction again the onus is on the German wikipedia to fix that not the English one. Nil Einne (talk) 10:47, 26 May 2016 (UTC)
- I'm not sure that the onus is on the German wikipedia, since our inclusion of fluorine as "essential" is decidedly idiosyncratic. -Nunh-huh 06:56, 26 May 2016 (UTC)
- Also, I'm not sure where you heard this: "why there have been lot of dead children which have eaten 2 tubes of toothpaste." but you might want to check your sources. I am skeptical that "many" children have died from eating 2 tubes of toothpaste. I found several sources repeating the claim that as little as 2 tubes of toothpaste "could" contain a lethal dose of fluoride for a child, but after some searching i can't find any reported cases of a child actually dying from eating that much toothpaste. I did find a clinical evaluation of 90 separate cases of children admitted to hospital from fluoride ingestion, which definitely has toxic effects, but none were fatal. Vespine (talk) 00:10, 25 May 2016 (UTC)
- And we should point out that the OP's apparent logic, that it can't be a vital nutrient if you can be poisoned from a mega-dose, is completely false. For example, iron is absolutely essential, and also toxic in mega-doses. StuRat (talk) 00:36, 25 May 2016 (UTC)
- The OP can always expand the English version. Fluoride appears due to some 20th century poorly conducted science which promoted this element as essential but which didn't take into account conflicting factors. This reality hasn’t filtered through yet to some circles. These things take time...--Aspro (talk) 02:02, 25 May 2016 (UTC)
- I'm curious: what article(s) are you referring to? Our Dietary element article says that fluoride is not strictly essential for life, but, since it helps prevent dental caries in small quantities, it could be considered essential for maintaining good health. --71.110.8.102 (talk) 21:39, 25 May 2016 (UTC)
- Which is why the article is bad. We shouldn't be misleading readers into thinking that fluoride is generally considered essential for life, and the current article does just that. It shouldn't be listed among the actually essential elements, as it currently is, with a note that one can conjure up an argument that it's beneficial, but it should be treated in another area, probably a footnote. A good article to use as a source might be this one at NIH that has a better definition of essential (An element that acts as a catalytic or structural component of larger molecules, with a specific function that is indispensable for life) than our article does. The article also contains a more authoritative list of those elements. - Nunh-huh 06:56, 26 May 2016 (UTC)
- What article is actually being referred to here? Dietary element#Other elements includes fluorine along with a bunch of other stuff such as arsenic and nickel and silicon and says "Many elements have been suggested as essential, but such claims have usually not been confirmed. Definitive evidence for efficacy comes from the characterization of a biomolecule containing the element with an identifiable and testable function". Earlier, it also has a periodic table where it lists these elements by colour code (including all those other elements). Fluorine deficiency doesn't have any lists although doesn't seem to be able to decide whether or no fluorine is essential. Nil Einne (talk) 10:36, 26 May 2016 (UTC)
- Which is why the article is bad. We shouldn't be misleading readers into thinking that fluoride is generally considered essential for life, and the current article does just that. It shouldn't be listed among the actually essential elements, as it currently is, with a note that one can conjure up an argument that it's beneficial, but it should be treated in another area, probably a footnote. A good article to use as a source might be this one at NIH that has a better definition of essential (An element that acts as a catalytic or structural component of larger molecules, with a specific function that is indispensable for life) than our article does. The article also contains a more authoritative list of those elements. - Nunh-huh 06:56, 26 May 2016 (UTC)
- I wonder if trace element should be converted into a true disambiguation page, instead of an "article" that is probably impossible to be more than a stub defining the various fields' meaning of "trace"? DMacks (talk) 03:10, 25 May 2016 (UTC)
- I took a pass at at least writing a unified intro that might explain why so little is written here. If there are specific existing places that Trace element (analytical chemistry), Trace element (biochemistry), and Trace element (geochemistry) can point, it can become a true DAB. DMacks (talk) 03:19, 25 May 2016 (UTC)