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September 22

Moonwalk suits in c. -100°F and brutal katabatic wind on Earth

How effective is the Apollo moonwalking suit for Earth, Mars and LEO? It's very heavy and they walked in mild temps but if you're just sitting or lying down in 100 mph gusts on top of Everest in winter how would the discomfort vs continuous duration graph compare to Luna? Let's pretend there's a helipad and shack at the top that's room temperature and pressurized so you start feeling 100% but with lowlanders' oxygen needs. What about Antarctica's worst windchill under hurricane force, or good and bad Martian weather? Or those marathon modern spacewalks? Sagittarian Milky Way (talk) 00:12, 22 September 2020 (UTC)[reply]

Let's also pretend Mount Everest is less than half as high as it is, since one would not be able to operate a helipad even in low-wind conditions at a height of 29,000 feet (8,800 metres). --Lambiam 10:51, 22 September 2020 (UTC)[reply]

Didier Delsalle literally landed at the tip. Sagittarian Milky Way (talk) 14:54, 22 September 2020 (UTC)[reply]

There have been some helicopter rescues on Mt. Everest about 6000 meters.[1] The 1996 rescue of Weathers and Gau at 6200 meters mentioned in that link is also detailed in Jon Krakauer's book Into Thin Air. 2601:648:8202:96B0:0:0:0:DDAF (talk) 06:20, 23 September 2020 (UTC)[reply]

Spacesuits, including the Apollo version used on the moon, are built to solve the opposite problem: they have to get rid of body heat. See Apollo/Skylab space suit and Liquid cooling and ventilation garment. It would be easy to add some heaters, but I don't think a spacesuit actually has them. The Primary life support system ("backpack") contains electronics, circulating water, and breathing air systems that would not function under those conditions. Worse, the pressure suit has flanges and other items that would provide a large thermal conductance to the environment in some places. I suspect the pressure helmet and neck ring would get very cold, and possibly break because of differential thermal contraction. The gloves have silicone fingertips that would freeze at -67°C. Summary: not a good choice. --Amble (talk) 23:00, 23 September 2020 (UTC)[reply]

Yep, this is a good example of how human intuition—which of course is "designed" for our comfy Earth environment—is misleading when it comes to space. Space is a vacuum, and vacuum is an ideal insulator because there's nothing to convect heat away. Your problem is getting rid of heat, not keeping it in. Manned spacecraft (and a spacesuit is really just a one-person spacecraft) boil away a working fluid to get rid of excess heat; the ISS uses ammonia. Spacesuits also have components that generally aren't needed on Earth, such as protection against radiation and micrometeorites. --01:24, 24 September 2020 (UTC) — Preceding unsigned comment added by 47.146.63.87 (talk)

Types of vets

If there are many types of physicians practicing human medicine, are there as many types of vets also? Our fellow mammals such as cats and dogs have organisms basically as complex as ours, after all. --Qnowledge (talk) 00:28, 22 September 2020 (UTC)[reply]

There are specialized parrot veterinarians, for sure. 146.200.128.134 (talk) 07:15, 22 September 2020 (UTC)[reply]

According to Veterinarian#Focus_of_practice there are (at least) eleven specialities. (According to the disambiguation page at vet there are ten types of vet.)--Shantavira|^{feed me} 07:47, 22 September 2020 (UTC)[reply]

There are the (US-based) Association of Reptile and Amphibian Veterinarians (who I believe are themselves mammals but treat animals in the Sauropsida clade), and The American Association of Fish Veterinarians. Some people keep a tarantula as their pet, but I did not readily find vets specializing in arthropods. I see some hints of people taking veterinarian psychiatry classes, but no substantial evidence that such classes are being offered, or of people practicing veterinarian psychiatry. --Lambiam 08:11, 22 September 2020 (UTC)[reply]

The list of Veterinary specialties has some animal groups not yet specifically mentioned here. --Lambiam 08:16, 22 September 2020 (UTC)[reply]

To really compare specialisations in vets with those among human doctors, we would be looking at those who specialise on different parts of animal anatomy. A few years back my dog had some expensive treatment from an orthopedic veterinary specialist. But, in the spirit of of having an article on everything, we have Veterinary specialties. It has a very long list of specialties. I've also encountered dog and cat psychologists. HiLo48 (talk) 08:32, 22 September 2020 (UTC)[reply]

I knew someone who got a prozac prescription for her neurotic cat (not sure whether it was from an ordinary vet, or a cat psychiatrist, or what) and the treatment mellowed the cat out quite a lot, even after being tapered off after a while. At the other end of the scale Dr. Igor Smirnov, DVM is one of the co-authors of the paper announcing discovery of the meningeal lymphatic vessels. His part in the discovery was doing a bunch of intricate brain surgery on mice. I could only think that surgery on humans must be trivial compared to that. The whole discovery was amazing. 2601:648:8202:96B0:0:0:0:DDAF (talk) 06:30, 23 September 2020 (UTC)[reply]

Perhaps that vet can prescribe Ritalin for my hyperactive chihuahua, who seems to have an attention deficit. --Lambiam 11:49, 23 September 2020 (UTC)[reply]

P vs V(isotherm) graph of real gas with critical temperature and critical pressure marked.

I want a P vs V graph for some real gas(say, CO₂), which shows the plots on a few temperatures, with plot at critical temperature as well, for comparison. I also want to have the representation of critical pressure on that very same graph. Also included should be the plot for Triple point temperature, with explanation for why the graph is that way. To sum up, there should also be a plot of the P vs V graph at Boyle's temperature.(fyi P= pressure, V= volume). Graph could be like this one:

— Preceding unsigned comment added by 16AdityaG09 (talk • contribs) 04:00, 22 September 2020 (UTC) <<clear}}[reply]

There are plots for CO₂ in the same Commons category as that one. Unfortunately they are jpegs and pngs rather than svgs. catslash (talk) 23:59, 22 September 2020 (UTC)[reply]

Correction: This one is svg, so you can easily change the language of the labels if you wish, or change °C to K, or re-label the y-axis in MPa if you don't like bar. catslash (talk) 00:12, 23 September 2020 (UTC)[reply]

Fortunately this SVG uses <text>...</text> for the text, which makes the editing of the text very easy. Many SVG on commons (and in the world in general) use graphical paths for text, which is only slightly easier to edit than a plain PNG. DMacks (talk) 13:45, 23 September 2020 (UTC)[reply]

Also, since it was created in Inkscape, it is very simple to open it again in that app and edit it there, which is easier than playing with the .svg file directly if you are not so familiar with editing such files. Michael D. Turnbull (talk) 14:14, 23 September 2020 (UTC)[reply]

If you do translate it, please consider uploading it to commons so others can benefit as well. See commons:Help:Translation tutorial#SVG_files for several technical ways if you don't have Inkscape. DMacks (talk) 14:29, 23 September 2020 (UTC)[reply]

As I'm fairly new to Inkscape, I tried this myself and uploaded the English version to Commons, as now coped here. I used the option to output the file in what Inkscape calls their optimised format, which reduces the file size and makes it much easier to use a text editor to make further alterations. Michael D. Turnbull (talk) 15:08, 23 September 2020 (UTC)[reply]

Nice! I renamed your file to "-en", per wiki-world standard to use two-letter language-codes, and fixed capitalization of "kg" in the x-axis also. There are a ton of spacing nits due to different SVG engines having inconsistent handling of superscript:( DMacks (talk) 03:58, 24 September 2020 (UTC)[reply]

Liquid elements

At what temperature are the most elements on the periodic table in liquid form?

User:Heyoostorm^_talk! 17:39, 22 September 2020 (UTC)[reply]

@Heyoostorm: It may depend on pressure, as we learn from the example of water (Water#Triple and critical points).

--CiaPan (talk) 17:46, 22 September 2020 (UTC)[reply]

Fair point, let's say normal atmospheric pressure. User:Heyoostorm^_talk! 17:49, 22 September 2020 (UTC)[reply]

At 2609-2673K there are 44 liquid elements, also 44 between 2719-2742K and 2750 to 2792K. (Data from List of chemical elements), ignoring post-actinides. Graeme Bartlett (talk) 22:50, 22 September 2020 (UTC)[reply]

Also it depends on allotropes for example white phosphorus melts lower than other forms. Graeme Bartlett (talk) 23:06, 22 September 2020 (UTC)[reply]

As Graeme Bartlett notes, we don't really know because no one has ever had enough of the heaviest elements to measure their melting points. In fact, we have the same problem with things like francium. Double sharp (talk) 07:20, 23 September 2020 (UTC)[reply]

Indeed, something like 1/5 of known elements we have never had enough atoms together in one place to take a reliable melting point. --Jayron 32 11:38, 23 September 2020 (UTC)[reply]

September 23

How come moderna can last at much more much higher temprature than Pfizer's?

I've read recently that Moderna's vaccine for covid-19 can last at around 60 degree more than Pfizer's. My question is why, given that they both use the same technique?--Exx8 (talk) 22:11, 23 September 2020 (UTC)[reply]

What do you mean by "can last at around 60 degree"? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:42, 23 September 2020 (UTC)[reply]

I'd like to know which degrees are being discussed here. Celsius? Kelvin? HiLo48 (talk) 03:49, 24 September 2020 (UTC)[reply]

The magnitude of a temperature difference measured in degrees Celsius is the same as when the unit is the kelvin, so why do you ask? --Lambiam 09:27, 24 September 2020 (UTC)[reply]

Well it won't be kelvin, because "the kelvin is not referred to or written as a degree". Mitch Ames (talk) 06:57, 24 September 2020 (UTC)[reply]

One specifies that it must be stored in liquid nitrogen or other quite low temperature dry ice, while the other just needs refrigeration. This greatly affects how it can be distributed. Pfizer's vaccine degrades in less than 24 hours at room temperature.[2] Graeme Bartlett (talk) 23:16, 23 September 2020 (UTC)[reply]

Just by way of clarification, Moderna's vaccine requires a transport temperature of -20°C [3]. This is a relatively easy temperature to reach with refrigeration, even most households freezers may be able to achieve it or at least very close although they probably lack the stability to be suitable for storage of the vaccine. Still it's outside the norm for most vaccines or drugs. Nil Einne (talk) 23:31, 23 September 2020 (UTC)[reply]

I don't know if it's been clearly published why Moderna's vaccine candidate can be stored at higher temperatures than BioNTech/Pfizer's, bearing in mind that these didn't exist 9 months ago and it's to some extent likely commercially sensitive. You can probably get some idea by looking at what was published previously on BioNtech and Moderna's platforms, especially their respective lipid nanoparticle encapsultations as I think these are biggest contributions. Nil Einne (talk) 23:31, 23 September 2020 (UTC)[reply]

Here we can read that Moderna's vaccine needs to be stored at temperatures not higher than −4 °F (−20 °C), while Pfizer's are reported to require a cool −94 °F (−70 °C). Both are developing mRNA vaccines, but these are different molecules and so may differ in stability and degrade at different temperatures. --Lambiam 09:36, 24 September 2020 (UTC)[reply]

September 24

Primary author

If there's an important biology paper with 10 authors, is it customary to list the primary author or principal investigator last? Alternatively would the main contributor come first? In the paper I'm thinking of, I believe the main result came out of joint work between the PI and a postdoc working for him, with various others also making contributions. The postdoc is listed first, then the others, and then the PI is last. It's a little bit odd that the PI's Wikipedia biography more or less describes it as a solo result by the PI. Not to diminish his contribution and maybe I have it wrong, but I thought in other places I'd seen, credit was apportioned between the PI and postdoc about equally. The paper is doi:10.1038/nature14432 which has all the names. They are not otherwise in alphabetical order or anything like that. I'm wondering whether I should adjust the wording in the biography, or alternatively bring it up on the biography's talk page. There are several separate biology articles related to the discovery itself, and those articles don't seem to have this issue. 2601:648:8202:96B0:0:0:0:DDAF (talk) 00:57, 24 September 2020 (UTC)[reply]

I have known European professors who insisted on always being listed first, even though the real work, also intellectually, had been done by an assistant. This was in a bygone era, in which the professor was also the director of a lab or suchlike, which he (never a she) could and did rule like a potentate. (I don't know how it was in these days in the US.) The argument was that then the publication was more likely to be accepted. With increased democratization and the rise of publish or perish, this is now often reversed: the doctoral students, who need publications to be considered for a tenure track, are listed before the authors who are tenured. But this is not universal. Next to alphabetical ordering, it is not unusual to attempt to order by the impact the authors had on the final publication. But, as you can imagine, determining that order is fraught with problems and potential conflicts. Yet another possibility is picking a random ordering. In short, there is no universal custom. Some methods may be more customary in specific fields; I have no specific experience or knowledge of the customs in biology. Some links to pages or articles that discuss this matter: [4], [5], [6] (paywall). --Lambiam 09:22, 24 September 2020 (UTC)[reply]

It definitely varies by field. In both mathematics and computer science, there's a very strong presumption in favor of alphabetical order, and inferring the degree of contribution from the author order is mostly useless and probably discouraged. --Trovatore (talk) 17:09, 24 September 2020 (UTC)[reply]

Should be random, Zhou never first Adam Aaronson always first. Sagittarian Milky Way (talk) 17:29, 24 September 2020 (UTC)[reply]

Alphabetical works fine as long as everyone knows it's alphabetical. The problem is the mix of conventions that muddles the interpretation.

In principle, order by level of contribution could theoretically work, if there were some objective way to determine it and people could keep their egos out of the way, but since I don't think either of those things is true it's probably a bad idea. Random could also work if it were used universally or near-universally, but as things stand, if you see authors not in alphabetical order, you likely assume it's by order of contribution, so random is also probably a bad idea. Alphabetical seems to be least bad. --Trovatore (talk) 17:48, 24 September 2020 (UTC)[reply]

These days, it's theoretically in order of merit, so to speak (at least in the biomedical field). As in, the people who contributed the most are the earliest in the author order. This is independent of student or staff status, it's about who did the work. The order might be a post-doc, an undergraduate, a PhD student, and a professor, for example. The last place is still reserved for the supervisor/line manager/head of the lab generally. There is of course a world of politics here too, so orders may not always reflect reality. For instance, in my last paper it was post-doc, post-doc, technician, professor, professor, professor. Did all the professors contribute? No, they did not... Anyway, you will find the specific author contributions at the bottom of many papers these days, those will be informative. Fgf10 (talk) 09:31, 24 September 2020 (UTC)[reply]

Thanks everyone. I have a clearer picture now, though I still don't know what if anything to do about the biography article. It's probably tolerable to just leave it alone, since it would be just another example of Wikipedia's occasional imprecision that we all live with. There is no sign of any any impropriety, but just some earlier WP editor writing from an incomplete picture, which happens all the time here.
Biology/medicine isn't my field at all so maybe I'm overglamorizing it, but this paper struck me as important to the point that "consideration for tenure" might be less of an issue than "consideration for Nobel" ;-). The article meningeal lymphatic vessels describes some of the background. If that's the case, it's something that science historians might want to document carefully someday. 2601:648:8202:96B0:0:0:0:DDAF (talk) 18:30, 24 September 2020 (UTC)[reply]

Whether justified or not, it is described here simply as "the work of Jonathan Kipnis", but here it is described as a discovery by Kipnis and Louveau, in that order, where the latter is described as a "research scientist who joined Kipnis' lab as a postdoctoral fellow". It is the first of seven publications by Louveau, all of which are co-authored by Kipnis. --Lambiam 19:41, 24 September 2020 (UTC)[reply]

Oh thanks, the "collaborators" pulldown of that Puretech page (the first of your two links) indicates that Kipnis is connected with a biomedical startup commercializing the discovery. So there might be some revisionism going on, that smells a bit like a marketing department at play. I better take a look at the revision history of the Kipnis biography. I remember the news reports at the time saying basically that Kipnis and Louveau were originally working on something a bit different involving studying mouse meninges under a microscope, using a new technique developed by Louveau. Louveau noticed these weird-looking vessels while looking for the other thing, and called Kipnis over to the microscope. Kipnis recognized (or maybe confirmed) their significance. Anyway, the authors continue to collaborate, so there's hopefully no real weirdness going on. 2601:648:8202:96B0:0:0:0:DDAF (talk) 20:16, 24 September 2020 (UTC)[reply]

Monocled cobras, regurgitating food

I have been watching the YouTube videos of a man, (Mizra Md Arif), in Odisha, India, who rescues venonmous snakes, from people. (And people from the snakes!) He goes to village homes/areas, and safely removes the snakes, for later release in a forest area. In three of the videos, after removal, the Monocled Cobras have regurgitated their prey. I am puzzled, as to why they should do this, as the process deprives them of nourishment, and leaves them vunerable, during the process.

I have watched twenty or more of his videos, and he does not mistreat the snakes, AFAICT, although being captured is stressful, of course. (Here are only two examples of his kind treatment. [7] [8])

In one video, two kittens were regurgitated,[9] and in another, three chicken/fowl eggs. The most amazing, was the regurgitation of a snake that had been eaten by the cobra. The first, 2/3, or so, looked fine, but the last part regurgitated, had been digested, so that all that remained were the vertebrate of the spine. (Can't find the link, just yet.) Any thoughts as to why the cobras would do this? Sorry if this is an unpleasant topic. I do understand that snakes require a regurgitation mechanisim, in case they are attempting to eat prey that is too large, etc.. but in the examples cited/seen, this did not seem to be a factor. Thanks! Tribe of Tiger ^{Let's Purrfect!} 01:41, 24 September 2020 (UTC)[reply]

Our article on snake says "a snake disturbed after having eaten recently will often regurgitate its prey to be able to escape the perceived threat. When undisturbed, the digestive process is highly efficient, with the snake's digestive enzymes dissolving and absorbing everything but the prey's hair (or feathers) and claws, which are excreted along with waste."--Shantavira|^{feed me} 08:05, 24 September 2020 (UTC)[reply]

@Shantavira: Well, I feel a bit silly, for not checking the Snake article! I thought this was something that only a cobra did, and it was not mentioned in the more specific Cobra article. (Obviously, it only belongs in the Snake artcle, of course.) Nonetheless, from viewing these videos, the cobra snake seemed fairly incapacitated during the regurgitation process, plus its fangs were blocked from defense. In the wild, if attempting to escape from a predator, I would think this response would be a disadvantage. But, perhaps the smaller body mass and the ability to maneuver with less energy expediture (in order to escape) would be the justification for this behaviour? So much metabolic energy is required for digestion, which may be used for escape. You were very helpful, thank you. Tribe of Tiger ^{Let's Purrfect!} 00:22, 25 September 2020 (UTC)[reply]

Remember that for a trait to be favoured by evolution, it doesn't have to work all the time, it just has to work more often than not. The world is probably too complicated for anything biological to work favourably in all possible circumstances. {The poster formerly known as 87.81.230.195} 2.219.33.80 (talk) 22:10, 25 September 2020 (UTC)[reply]

Also, the predator may decide that the regurgitated food is an easier target than the snake. "Predator" and "scavenger" are not truly exclusive terms and many animals do not exhibit the aversion to regurgitant that humans do. --Khajidha (talk) 14:29, 27 September 2020 (UTC)[reply]

Has it ever been definitively determined why gulls chase ships?

The obvious answer would be "because people on the ship feed them", but I have also seen it suggested that they're mainly doing it so they can slipstream the ship and that they chase it still even when there's no food. 146.200.128.134 (talk) 02:15, 24 September 2020 (UTC)[reply]

It may be a combination of factors. Following a ferry has both a cost and a possible reward. Apparently, the air streaming over the ship can help the gull to soar,^[10] which requires very little energy, greatly reducing the cost. (Aside: Once, taking the ferry from the European side of Istanbul to the Princes' Islands, which is always accompanied by a flock of gulls, with passengers often throwing them pieces of bread or simit, I noticed from the corner of my eye that one of the birds was flying awkwardly. When I looked, I saw a crow flying merrily in the midst of the flock of gulls – but, not built for soaring, it had to keep flapping its wings to keep up.) Often the food thrown will be enough of a reward, but if a boat is heading the way a gull would have gone anyway, I can imagine they appreciate the free ride. Next to ferries and cruise ships carrying passengers, they are reported to preferentially follow fishing boats, diving in the wake to pick up scraps thrown overboard.^[11] --Lambiam 08:58, 24 September 2020 (UTC)[reply]

There's a WWII naval anecdote about an old merchant ship converted into a dummy battleship at Scapa Flow to confuse German reconnaissance aircraft. 'A signal went across to them one day from the Commander-in-Chief; “Feed your seagulls”.' [12] All the real warships in the harbour had an attendant flock of seabirds feeding on the rubbish (or "gash") thrown overboard. 176.227.136.190 (talk) 15:30, 24 September 2020 (UTC)[reply]

Measuring ageing rate

Are there any measurement methods for human ageing rate (possibly telomere length measurement, etc) to verify if a person indeed ages slower compared to some baseline? This is partially inspired by the fact that, despite being 34, I was asked several times to show ID when buying alcohol to prove I'm above 18 (although I was masked due to pandemic, and at least once I was checked so at a nightclub entrance); and 4 years ago when I went to a free cardiovascular checkup, the guy stated that based on my data my heart was younger by two years (meaning the heart was reportedly working as if in 28). 212.180.235.46 (talk) 11:36, 24 September 2020 (UTC)[reply]

Telomere length is variable on the individual cellular level, given the trillions of cells in your body right now, I'm not sure that's a practical way of taking a survey of your "biological age". If you want a good overview, the biological process of aging is called Senescence, and it would make a good starting point for your research. Keep in mind that trends in aging can be measured statistically over large numbers of people, but your individual aging process is affected by an irreducible melange of environmental and genetic factors and while we can say that "people", writ large over billions of samples, follow certain trends in the aging process, we cannot necessarily say that you have aged how you have for any specific reason. --Jayron 32 11:46, 24 September 2020 (UTC)[reply]

By the time I was 16 I had to buy cigarettes and drink for all my friends as I was told I looked to be in my late 20's. Then in my early twenties I was told that I must be "...well into your 30's?" Just FYI. I have never been asked for ID 86.186.232.90 (talk) 12:46, 24 September 2020 (UTC)[reply]

Exercise performance. Count Iblis (talk) 17:59, 24 September 2020 (UTC)[reply]

EX39 Exclusionary Mogul Screw Base

I'd like to add a description of the EX39 Exclusionary Mogul Screw light bulb base to Edison screw#Types, as described on this "bulbamerica.com" page: What is the difference between E39 and EX39 base?. Can you help me find a better reference, preferably an industry specification? -- ToE 18:12, 24 September 2020 (UTC)[reply]

Does this ref work for you? If I understand correctly, the "39" and "Mogul" mean the same thing with respect to bulb bases, and the "X" signifies an eXtended contact tip (aka "eyelet"), as illustrated in the source linked to. --Lambiam 08:06, 25 September 2020 (UTC)[reply]

Yes, with respect to bulb bases, "Mogul" is synonymous with E39 (39mm Edison screw). And yes, the difference is the extended center contact, though I believe the "X" is for "eXclusionary". The extended tip of an EX39 bulb allows its use in either an E39 or an EX39 socket, but the ceramic ridge around the center of an EX39 socket excludes operation with an E39 bulb as it prevents the bulb from fully seating and making contact with the center electrode.

The "bulbamerica" page indicates that this is to prevent a bulb rated only for enclosed fixtures (and equipped with an E39 base) from being used in an open fixture (equipped with an EX39 socket), while allowing bulbs rated for open fixtures (and equipped with an EX39 base) to be used in either open or closed fixtures.

Thanks for that ref. At least it does illustrate the difference between the two bases, though it doesn't address the purpose. What I still don't know is if the open enclosure exclusion is an issue of weather exposure of UV shielding. (One use of these bases is with some HID lamps.) -- ToE 12:56, 26 September 2020 (UTC)[reply]

Funny that the "bulbamerica" page shows left-handed threads. I wonder if they reflected the images without thinking at some point, or did so to mask having copied them from another souce. -- ToE 12:56, 26 September 2020 (UTC)[reply]

If the species disappeared instantly how long will average books on shelves stay readable in different climates?

I'm guessing that jungle is one of the worst climates, Northeast America and North Europe somewhat better and Egypt is better still as there are readable papyri from 26th century. Are there better climates than Egypt? Can it be too dry? Is cold and dry better than hot and dry? Is heat or cold bad, or just constant temperature swings or freezing cycles like Mongolia or not even that? Is altitude good? How much windowlight do you need to cause extra exterior fading of a well-preserved for its age but still almost unreadable bookshelf book? Sagittarian Milky Way (talk) 20:26, 24 September 2020 (UTC)[reply]

This requires speculation or prediction which the Ref Desk doesn't do. Richard Avery (talk) 21:22, 24 September 2020 (UTC)[reply]

The fundamental question the OP is asking is "How well books / paper last in various environmental conditions". That sounds like the sort of thing that will have been studied by archivists and curators, so even if the exact answer cannot be given, a useful or approximate one ought to be possible. Here are a couple of links that may be relevant: [13] [14] Iapetus (talk) 09:17, 25 September 2020 (UTC)[reply]

Yes, so cool and dry and dark is best, if the cooler the better then it's stations like Vostok and Amundsen-Scott, only ones that avoid disasters like asteroids which we can't crystal ball. If dry and cool but not freezing is best then maybe villages of certain height near the equator? I'm betting Ethiopia, Andes or Kenya. Sagittarian Milky Way (talk) 19:42, 25 September 2020 (UTC)[reply]

Or Hawaii as their rain shadows actually work, with no wet season. But Kauai has had a cat 4, no way could any island avoid one for 10,000+ years. Maybe some high altitude village in the general vicinity of Ethiopia or Yemen. Sagittarian Milky Way (talk) 19:58, 25 September 2020 (UTC)[reply]

I don't know about the last 10,000 years, but most of the islands of the Indonesian archipelago have never recorded a Typhoon/Hurricane/Cyclone. They are subject to earthquakes, tsunamis and volcanism though, and torrential seasonal rain. Not a great environment for preserving your old books. Handschuh-^{talk to me} 00:51, 28 September 2020 (UTC)[reply]

Here's a cool graphic to go with that statement: [15]. Handschuh-^{talk to me} 00:53, 28 September 2020 (UTC)[reply]

Right, too close to the doldrums in wet season. Would probably mold without air conditioning. Hawaii has desert but books might be blown all the way to the ocean after building destruction. Sagittarian Milky Way (talk) 01:26, 28 September 2020 (UTC)[reply]

Yeah, waaaaaay to many variables to consider, including what caused us to be gone, and what conditions would befall everything else with us gone (i.e. ancient Egypt didn't contend with nuclear reactors following an absence of human operators and maintenance). --OuroborosCobra (talk) 21:33, 24 September 2020 (UTC)[reply]

The calculator at http://dpcalc.org/ gives some insights to what conditions cause the worst damage to "collection materials for libraries, museums, and archives". (No idea how accurate it is.) You can put in real life typical weather conditions for various places and have a guess. Possibly the series Life After People also talked about this. 93.136.39.38 (talk) 21:34, 24 September 2020 (UTC)[reply]

It doesn't seem to work on mobile but thanks for the link, I'll use it later at a library computer or something. Sagittarian Milky Way (talk) 20:15, 25 September 2020 (UTC)[reply]

September 25

Crazy seeds

I am looking for further information concerning a plant that grows wild in Southern Africa especially near the eastern coast. In Afrikaans they are referred to as Malpitte (spelling?) or Crazy seeds, perhaps crazy pips. I am curious to know the Latin name for this plant and what the active ingredient is that makes people mad if the seeds are eaten. Thank you 86.186.232.90 (talk) 08:15, 25 September 2020 (UTC)[reply]

Google gives this directly on a search for Malpitte. Apparently they are Datura stramonium, Jimsonweed, — not a South African native but widely distributed. Michael D. Turnbull (talk) 10:18, 25 September 2020 (UTC)[reply]

And our article says the toxins are atropine, hyoscyamine, and scopolamine. Graeme Bartlett (talk) 11:45, 25 September 2020 (UTC)[reply]

I've seen Jimsonweed growing wild in Riverside County, California. Seemed happy in the baking sun. Regards, Zindor (talk) 14:57, 27 September 2020 (UTC)[reply]

Can childhood sexual assault lead to low grade squamous intraepithelial lesion (LSIL) findings later in adulthood?

To what degree can child sexual abuse confound LSIL findings on a cervical or rectal PAP smear years or decades later in adulthood? Yanping Nora Soong (talk) 20:09, 25 September 2020 (UTC)[reply]

The Supreme Court did a horrible thing when it made the death penalty for child rape cruel and unusual punishment. Sagittarian Milky Way (talk) 20:17, 25 September 2020 (UTC)[reply]

Please stay on topic, Sagittarian. --OuroborosCobra (talk) 20:32, 25 September 2020 (UTC)[reply]

LSIL (Low-grade squamous intraepithelial lesion) is a common abnormal result on a woman's cervical Pap test. It may be caused by HPV infection but 90% of cases clear up without treatment within 2 years. There are many possible causes of mild inflammation seen on a Pap test, such as allergies to spermicides or latex in condoms, that need no treatment. See Tai YJ, et al. (2017). Clinical management and risk reduction in women with low-grade squamous intraepithelial lesion cytology: A population-based cohort study. DOI: 10.1371/journal.pone.0188203. Anal pap smears from males and females are similarly examined by a pathologist looking for pre-cancerous or dysplastic changes.

A study of evidence in child sexual abuse Sexual Assault Evidence: National Assessment and Guidebook, R. E. Gaensslen Ph.D. ; Henry C. Lee Ph.D. finds abnormal Pap smears in only a small proportion of rape victims. This seems to be considered only as evidence of recent trauma with no expectation of a decades old causation. 84.209.119.241 (talk) 21:59, 26 September 2020 (UTC)[reply]

September 26

What's the lowest specific gravity recorded for a drinkable wine?

What's the lowest specific gravity recorded for a drinkable wine? Also, could it be that a wine will have as low gravity as 960-965 or around it? (according to google the normal range is between 992-996, but I didn't find more information regarding my question) ThePupil (talk) 01:41, 26 September 2020 (UTC)[reply]

That would have a 20% or more alcohol concentration, which yeast does not make in wine.[16] If you heated up your wine, perhaps you could get the density that low. Graeme Bartlett (talk) 01:45, 26 September 2020 (UTC)[reply]

The requirement for 20% or more alcohol is based on the assumption that only alcohol affects the density, or there are other factors that have an effect on the final specific gravity?--ThePupil (talk) 02:14, 26 September 2020 (UTC)[reply]

In closed container that won't explode of course. Sagittarian Milky Way (talk) 01:54, 26 September 2020 (UTC)[reply]

If you check out the reference I gave, you can see there is quite a difference due to temperature. But supercritical wine could be quite low in density. Yet another way to lower density is via bubbles - EG carbonated wines. Graeme Bartlett (talk) 06:31, 26 September 2020 (UTC)[reply]

And maybe if you heat it in an open container fast enough it won't evaporate more alcohol than water fast enough to prevent temporarily reaching 960. Sagittarian Milky Way (talk) 13:59, 26 September 2020 (UTC)[reply]

Fortified wine can have up to a 20% ABV, in the EU even up to 22%. For lower ABV values, the wine has to have a high percentage of ether and ester components, which in low percentages are what (next to sweetness from sugars and tartness from acids) give wine its specific nose. I have no idea how high up this can go before it becomes so overwhelming that it turns the wine undrinkable, or makes one pass out by sniffing it. --Lambiam 08:59, 26 September 2020 (UTC)[reply]

You can mitigate acid fault through Malo-Lactic fermentation (MLF) which converts Malic acid into Lactic acid. Lactic being more pleasant. Although I've drunk both acids and they weren't too nasty.

You'll typically get more acid from grapes that have lower sugars. Sugar in grape juice is measured by its refraction relative to distilled water, the unit for this is Brix.

From my brief time in the Southern California wine industry, I recall 18-23 brix being a good range for white wines and around 24 for red, although for heavier GSM blends maybe up to 28 brix could be possible given a strong season.

There's a relationship between sugars and alcohol, and therefore specific gravity, so perhaps you could look at the brix levels for different regions to work this out.

For low sugar/alcohol my guess would be sparkling Syval Blanc from Northern England, without added fructose. Alsace is a low-brix region in bad seasons, but I know they often add sugar. Higher sugar/alcohol regions would probably be ones in Australia growing grapes like Shiraz etc

Being drinkable is a bit subjective, for instance some people find the creamyness from oak-exposed Chardonnay nice, whereas others massively prefer Chardonnay that's only ever been in steel vessels. Regards, Zindor (talk) 16:18, 26 September 2020 (UTC)[reply]

And some of us have never found a wine that could be considered drinkable at all. --Khajidha (talk) 03:16, 27 September 2020 (UTC)[reply]

Us with better taste, that is :} 93.142.121.167 (talk) 18:53, 27 September 2020 (UTC)[reply]

I always laugh at people who say "you have the taste buds of a child" and things like that, because apparently bullying and peer pressure are more mature than liking tater tots. --Khajidha (talk) 15:06, 28 September 2020 (UTC)[reply]

Jumping ability of kittens compared to that of cats

At what age is the jumping ability of kittens 99% from that of mature cats? Thanks.--109.166.129.7 (talk) 18:02, 26 September 2020 (UTC)[reply]

At week 7, they can: confidently jump off of furniture and week 8: Their agility and coordination will be nearly fully developed.

Sullivan, Megan (Jan 22, 2018). "Kitten Development: Understanding a Kitten's Major Growth Milestones". www.petmd.com.

2606:A000:1126:28D:ADC6:7A08:1D3C:354B (talk) 19:18, 26 September 2020 (UTC)[reply]

That page only addresses jumping down, though. --174.89.48.182 (talk) 20:32, 26 September 2020 (UTC)[reply]

Has this author or the other veterinarian authors mentioned at the site written something about the development of kittens beyond the 8th week, like around 14-15 weeks? The context of the previous question is given by having watched a kitten of about 14 weeks who seems not to be able to jump a height jumpable by mature cats (like its mother) in order to reach roofs in the yard of a house nearby where it has been living in the past 2-3 months, accidentally sometimes falling from the mentioned roofs, but succeeding in getting back on roofs (with or without mother cat's help) by going around the yard where the walls are easier to climb due to lower height than the height of falling and to additional supporting elements on the wall that facilitate climbing and not jumping like metal wires and/or brick contours. But in the past 3-4 days it has not been able due to some unknow factors to get back on roofs, thus remaining at ground level and crying after midnight or early in the morning and hiding during the day, now that at this age its mother is no longer very present around it to guide it in case it has forgotten how to go around the walls of the yard for an easier climbing.--109.166.129.7 (talk) 21:05, 26 September 2020 (UTC)[reply]

There's a discussion by non-professionals about a 22-week-old kitten with similar problem (here). It could just be reluctance due to a previous mishap. Or (less likely) it could be related to something like Cerebellar hypoplasia (non-human). "I'm not a veterinarian but a play one on Wilipedia." 2606:A000:1126:28D:ADC6:7A08:1D3C:354B (talk) 03:14, 27 September 2020 (UTC) ... In the 1st case, mom will probably work things out; you can boost its confidence by encouraging it to make progressively longer/higher jumps. You should check to see if it limps or is otherwise impaired. As always: "consult a professional" (rather than random folks on the internet). [04:00, 27 September 2020 (UTC))][reply]

It doesn't limp or seem impaired. It is an outdoor kitten from the neighbouring house that can be seen from my apartment window so I can't do much to help it with jump encouragement. It has just come out of hiding, but has returned to the unknown/unspotted hiding place after trying to follow him.--109.166.129.7 (talk) 10:57, 27 September 2020 (UTC)[reply]

I've just seen the mother cat of the kitten at the usual spot on the roof of the kitchen from the yard where there is a small window where the people from the house put some food and water for outdoor cats. It seems that the timing of encounter has been missed, it would have been an interesting moment to see whether the mother on the roof would do something when hearing the kitten (at this age) crying for help at the ground level near the wall of the house kitchen.-- 109.166.129.7 (talk) 11:33, 27 September 2020 (UTC)[reply]

You might get better answers on pets.stackexchange.com. —Tamfang (talk) 00:57, 29 September 2020 (UTC)[reply]

September 27

proteun

Which protein in dogs help them to smell so well?Acidic Carbon (Corrode) (Corrosive liquid) 12:21, 27 September 2020 (UTC)[reply]

The keen sense of smell of dogs has to do with the high quantity of Olfaction receptors they have. ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:08, 27 September 2020 (UTC)[reply]

Baseball Bugs Thanks! Acidic Carbon (Corrode) (Corrosive liquid) 13:12, 27 September 2020 (UTC)[reply]

Acidic Carbon , see also More fat, less protein improves canine olfactory abilities (Cornell University, 2013). Alansplodge (talk) 13:30, 27 September 2020 (UTC)[reply]

Alansplodge Wow!But do dog olfactory cells work the same way?Acidic Carbon (Corrode) (Corrosive liquid) 13:39, 27 September 2020 (UTC)[reply]

Sorry, I can only tell you what is written in the article. Alansplodge (talk) 15:04, 27 September 2020 (UTC)[reply]

And anther advantage for dogs, is that their nose is often close to the ground, or other things. Graeme Bartlett (talk) 21:50, 27 September 2020 (UTC)[reply]

Dogs also possess a vomeronasal organ,^[17] an additional olfactory sense organ. (There is still debate over whether humans have one, but if so then it is at best rudimentary or vestigial in most humans and very likely hardly or only marginally functional.) But this, or their sniffing from a close distance, is not enough to explain that the canine olfactory sensitivity is up to 100,000 times that of the average human.^[18] One factor is the larger number of olfactory receptor cells, made possible by a vast olfactory epithelium.^[19] An olfactory receptor cell is specialized to respond to a specific odorant. Probably, there is a larger variety in the odorants canine receptor cells respond to, explaining the canine ability of discriminating between a larger variety of similar smells and following one specific smell trail. --Lambiam 09:44, 28 September 2020 (UTC)[reply]

Do siblings with more similar chromosomes look more similar?

Given the size of the World's population, there should exist a few siblings with 15 identical chromosome pairs. Do such siblings look like identical twins? Count Iblis (talk) 19:59, 27 September 2020 (UTC)[reply]

Chromosomes aren't really inherited as a whole. Crossing over and spontaneous mutations mean that the chromosomes you inherited from each parent do not exactly match the ones that they have, much less the ones that your siblings would inherit. --Khajidha (talk) 20:32, 27 September 2020 (UTC)[reply]

To build on what Khajidha said, it despite the size of the world population, it is incredibly unlikely that any siblings share identical chromosome pairs outside of cases such as identical twins. That there are 7 billion some odd people doesn't make it appreciably likely that even a single non-identical twin set has that level of genetic similarity. Even if you want to consider spontaneous mutations rare (which they aren't, it's just that most of the time the results are benign), chromosomal crossover during sexual reproduction is NOT rare. The same goes for genetic changes during meiosis in the production of gametes. If the gametes themselves are not genetically identical even within a single parent, then offspring produced with different gametes, even from the same set of parents, stand basically no chance of being genetically identical. --OuroborosCobra (talk) 00:22, 28 September 2020 (UTC)[reply]

September 28

Near-rectilinear halo orbit

What is a Near-rectilinear halo orbit? The article says what it might be used for, but doesn't say anything about what it is. Handschuh-^{talk to me} 00:35, 28 September 2020 (UTC)[reply]

A halo orbit but more rectilinear. Sagittarian Milky Way (talk) 01:03, 28 September 2020 (UTC)[reply]

What would we do without you! —Tamfang (talk) 01:29, 29 September 2020 (UTC)[reply]

The linked ESA video in the article's 'External links' section depicts a Lunar NRHO and also describes it textually thus:

"Instead of orbiting around the Moon in a low lunar orbit like Apollo, the Gateway will follow a highly ‘eccentric’ path. At is closest, it will pass 3000 thousand km from the lunar surface and at its furthest, at 70 000 km. The orbit will actually rotate together with the moon, and as seen from the Earth will appear a little like a lunar halo."

This means it will look like an elongated oval with the Moon towards one end, and will remain face-on to Earth. {The poster formerly known as 87.81.230.195} 2.219.33.80 (talk) 03:21, 28 September 2020 (UTC)[reply]

So that sounds like it's not a halo orbit at all? It's directly orbiting the Moon, not a Lagrange point, right? Handschuh-^{talk to me} 03:53, 28 September 2020 (UTC)[reply]

I guess the term "near-rectilinear" is a variation on the term "almost rectilinear" introduced in the 1984 paper "Almost Rectilinear Halo Orbits" by Kathleen Howell and John V. Breakwell. In that paper they use the term "halo orbit" for any of the "periodic orbits emanating from the general vicinity of any of the 3 collinear Lagrangian libration points", abandoning the notion that the orbit is orbiting an L[1..3] point. This is a still image visualizing the planned orbit as seen from outside the Earth–Moon system. And here is a video visualizing it. --Lambiam 08:07, 28 September 2020 (UTC)[reply]

I came across that video before and found it very good at illustrating what the orbit looks like. It sort of vaguely shows how it relates to actual halo orbits, glossing over the mathematics behind it (which I'm happy with), but also glossing over how they can still call the orbit a "halo orbit" when the object is orbiting the barycenter of the system, not the L2 point that they start the explanation from. If the influence of the further primary's gravity (i.e. earth in the example from the movie) is what keeps the orbit "rectilinear", then I guess I can see how they trace the thinking from the concept of the L2 halo orbit through to the NRHO, but it still seems like it's no longer meeting the definition of a halo orbit. Handschuh-^{talk to me} 09:41, 28 September 2020 (UTC)[reply]

The object goes around the barycentre in an inertial frame, as is true for all halo orbits. But what is its orbit in a rotating frame that keeps the Earth–Moon line stationary? --Lambiam 10:06, 28 September 2020 (UTC)[reply]

"The object goes around the barycentre in an inertial frame, as is true for all halo orbits." I don't see how this can be true. Take for example the orbit of the James Webb Space Telescope around the Sun-Earth system, shown here. If I imagine the inertial reference frame wrt to the Sun-Earth system, with the sun, earth and L3 point all held stationary, the JWST would just oscillate around the L2 point, never going around the barycenter, which would still be well within the sun. Handschuh-^{talk to me} 08:05, 29 September 2020 (UTC)[reply]

Viruses

In the main page of viruses, there is a picture of a cgi image. Can you please remove the fake, cgi image and replace it with a an actual image of a virus via the electron microscope? Thank you, I hope this is done sooner than later. — Preceding unsigned comment added by 2600:1008:B054:93:C8E9:B631:A283:DDB3 (talk) 20:45, 28 September 2020 (UTC)[reply]

Do you mean File:SARS-CoV-2 without background.png? Look the thing to do is to discuss it at Talk:Virus. Nothing about it can be done from here. --Jules (Mrjulesd) 20:51, 28 September 2020 (UTC)[reply]

There's an electron microscope image on the Coronavirus page. So what's stopping YOU from posting a different illustration on the Virus page, if you think it's so urgent? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:30, 28 September 2020 (UTC)[reply]

Its semi-protected. --Jules (Mrjulesd) 22:06, 28 September 2020 (UTC)[reply]

The reviled image is meant to illustrate the morphology of the COVID-19 virion, and it does a good job at that. There is already an image taken using a transmission electron microscope, which is about the best you can do, but it makes the virions look like pancakes with wattles and leaves you in the dark about crucial aspects of their morphology. --Lambiam 22:15, 28 September 2020 (UTC)[reply]

It's also incorrect to call the image "fake." You won't find a snapshot image of DNA on the DNA article either (except possibly in the nanotechnology section, but even that's not exactly a traditional image). Rather, you see images that are constructed based on interpreting things like x-ray crystallography that give us fairly high resolution atomic level structures, but not images. In the case of SARS-CoV-2, we have done similar atomic level structures with techniques like Cryogenic electron microscopy, but even then it's usually of individual structure units, such as the spike protein. The CGI image isn't fake; it's a composite of the structures we have measured individually using other techniques that are not suitable for measuring an entire virus structure at once. --OuroborosCobra (talk) 01:07, 29 September 2020 (UTC)[reply]

September 29

@@ Line 250: / Line 250: @@
 ::::I came across that video before and found it very good at illustrating what the orbit looks like. It sort of vaguely shows how it relates to actual halo orbits, glossing over the mathematics behind it (which I'm happy with), but also glossing over how they can still call the orbit a "halo orbit" when the object is orbiting the barycenter of the system, not the L2 point that they start the explanation from. If the influence of the further primary's gravity (i.e. earth in the example from the movie) is what keeps the orbit "rectilinear", then I guess I can see how they trace the thinking from the concept of the L2 halo orbit through to the NRHO, but it still seems like it's no longer meeting the definition of a halo orbit. '''[[user:bobby1011|Handschuh]]'''-<sup>[[user talk:bobby1011|talk to me]]</sup> 09:41, 28 September 2020 (UTC)
 :::::The object goes around the barycentre in an inertial frame, as is true for all halo orbits. But what is its orbit in a rotating frame that keeps the Earth–Moon line stationary? &nbsp;--[[User talk:Lambiam|Lambiam]] 10:06, 28 September 2020 (UTC)
+::::::"The object goes around the barycentre in an inertial frame, as is true for all halo orbits." I don't see how this can be true. Take for example the orbit of the [[James Webb Space Telescope]] around the Sun-Earth system, shown [https://www.youtube.com/watch?v=IyyQqaF4tNY&ab_channel=FraserCain here]. If I imagine the inertial reference frame wrt to the Sun-Earth system, with the sun, earth and L3 point all held stationary, the JWST would just oscillate around the L2 point, never going around the barycenter, which would still be well within the sun. '''[[user:bobby1011|Handschuh]]'''-<sup>[[user talk:bobby1011|talk to me]]</sup> 08:05, 29 September 2020 (UTC)
 == Viruses ==