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April 12

Interpreting the Archeology of the Cueva de las Manos Site

What does this source, Advances in the Archaeology of the Pampa and Patagonia, say about the Cueva de las Manos site? More specifically, what is the layman's interpretation of the archeological information presented on the site? I'm looking to distill any of the information on Cueva de las Manos in the article into a non-technical form that is more approachable for a general audience. Thank you in advance! Tyrone Madera (talk) 02:16, 12 April 2021 (UTC)[reply]

I do not see material in this article that is readily adoptable to being translated into layman's terms beyond what we already have. It is a lengthy review article (81 pages), mostly rather technical and involved with dating, based on geological and archaeological findings, as presented in the (in 1987) more recent literature. This is put in a larger context of classifying cultural artifacts according to cultural-tradition phases (with such names as Magellan I, II, III, IV and V, Toldense, Casapedrense, Patagoniense). A great deal of the many mentions of Cueva de las Manos are in various tables; in most other cases, they are in an enumeration, as in, for example, "The apparent persistence of the Toldense phase until the third or second millennium B.C. at Cueva de las Manos, Cueva del Arroyo Feo, Cárdenas, and Cerro Casa de Piedra was mentioned earlier." Gradin is called "the principal authority on indigenous Pampean-Patagonian art", with respect to the Cueva de las Manos specifically referring to Gradin et al. (1977, 1981). The 1977 publication is referenced in our article, while the 1981 publication is: Gradin, C. J., Aschero, C. A., and Aguerre, A. M. (1981). Arqueología del área Rio Pinturas (provincia de Santa Cruz). Relaciones de la Sociedad Argentina de Antropología 13: 183–227. --Lambiam 08:48, 12 April 2021 (UTC)[reply]

Lambiam, Thank you! Yeah, I didn't know exactly what to make of the data, but I guess interpretation would qualify as OR. Thank you for reading this long, extremely detailed article. I'm glad that someone with more scientific experience than I was able to have a go with it :) Tyrone Madera (talk) 15:52, 12 April 2021 (UTC)[reply]

P.S. Are you able to access doi:10.1093/oxfordhb/9780199271016.013.0031 and doi:10.1080/20555563.2020.1757859 to see if either has info on Cueva de las Manos as well? Thanks again! Tyrone Madera (talk) 17:49, 12 April 2021 (UTC)[reply]

The former publication, a book, does not mention the site in the running text but contains a brief description in an appendix with information on sites:

Cueva de las Manos (Argentina)

This is perhaps the best-known site in the country, because of its evocative zoomorphic, anthromorphic, and geometric rock-art panels. It is located in the canyon of the Pinturas River in the north-eastern section of the province of Santa Cruz. The lowest levels have been dated to 9320 ± 90 bp and contain scrapers, arrowheads, nuclei, and other lithic tools. Chert is the predominant material used for this industry, although basalt and chalcedony, and small amounts of obsidian, are also present. The faunal assemblage includes Lama guanicoe, foxes, felines, and fish.

(I wouldn't consider the location to be in the north-eastern section, being more to the west, but this is what the text says.)

The latter publication, a journal article, mentions the site three times: in the caption of an illustration of stemless projectile points (SPPs) in central-western Santa Cruz province, showing a siliceous SPP from Cueva de las Manos; in the caption of a map of site locations; and in a table of earliest stratigraphic radiocarbon dates for SPP chronology, giving 9320 ± 90 ¹⁴C yr BP for Cueva de las Manos. (I wouldn't consider the location of Cueva de las Manos to be in central-western Santa Cruz province, being more to the north than to the middle, but this is what the text says.) --Lambiam 11:38, 13 April 2021 (UTC)[reply]

Lambiam, Thank you so much! I haven't been able to access the texts, so your summaries mean a lot to me. Tyrone Madera (talk) 15:30, 13 April 2021 (UTC)[reply]

Do you have a page number or location I could use in a citation for "the best-known site in the country"? Tyrone Madera (talk) 15:53, 13 April 2021 (UTC)[reply]

Page 986. Just to be sure, this is the printed hardcover edition, ISBN 978-0-19-927101-6. There are, however, also pdf's carrying the same ISBN where this text appears on page 695. I have not examined the source of the discrepancy. --Lambiam 20:01, 13 April 2021 (UTC)[reply]

Relative speed of healing

After an anonymous cat brought in an anonymous mouse, an anonymous person managed to rescue the mouse and set it back outside. That made me wonder: Smaller animals have smaller bodies and, if they are injured, typically injuries are, in absolute terms, small. I've had cuts in my finger that would amputate legs from a mouse, and I've left enough skin on mountain-bike trails to cover several mice. Small animals also typically shorter lifetimes. So I wonder: How fast do animals of different size heal? Is there a constant "healing speed"? Will it always take the same time to heal a broken leg, or is the time proportional to the cross section of a broken leg? Or does the different speed of different metabolisms mean that injuries can heal at very different absolute and relative speeds? In case you wonder: In the concrete case, both the culprit and the victim seem to have escaped serious harm. I'm less certain about the anonymous person, but (s)he will recover ;-). --Stephan Schulz (talk) 07:53, 12 April 2021 (UTC)[reply]

I was more wondering about the anonymous cat. After all, everyone knows that a cat must have three different names. --184.147.181.129 (talk) 08:01, 12 April 2021 (UTC)[reply]

Probably directly correlated to the width of the wound, with some contribution from the depth, and very little from the length. This is just my guess, given that wound healing is accomplished by cells dividing, crawling around and rebuilding basement membranes with collagen that they have to make. These processes are governed by the rate that cytoskeletal proteins can be assembled and disassembled. Also, mammalian cells are all roughly the same size, so there will be no advantage or disadvantage for a small or large organism. But I could be totally wrong... Abductive (reasoning) 09:03, 12 April 2021 (UTC)[reply]

April 13

High-resolution topographic maps of European countries

I'm looking for high-resolution topographic maps without any labelling, no indication of cities or other human footprint, etc. - just the plain topography of the country, if possible with the biggest rivers. [Longitudes and latitudes would be welcome, but aren't necessary.] The maps are to be printed on 30 x 40 cm or similar, depending on the shape of the country. For smaller countries, e.g., Netherlands / Belgium / Luxembourg, I don't mind one map with all of them together.

I've found one huge map of France by random internet browsing, but no others yet. Any ideas where to look?

(It's to expand a sort of quiz game, in which players have to guess where cities, landscapes, and mountain ranges are; only the mountain ranges are visible though. German version: de:Deutschland: Finden Sie Minden.)

Thanks for your help, Ibn Battuta (talk) 09:23, 13 April 2021 (UTC)[reply]

This map here may be helpful. There's a variety of layers you can switch through and turn on/off. It may meet your requirements. Not sure. But it's one option I have found. --Jayron 32 12:21, 13 April 2021 (UTC)[reply]

Thanks, some of the layers look great! (no rivers, but apart from that: perfect!) I'm just not sure how to download from the site, let alone in high resolution? --Ibn Battuta (talk) 12:52, 13 April 2021 (UTC)[reply]

Most computers and/or phones have a screen capture function, and any image-editing program should have the ability to crop an image. --Jayron 32 14:46, 13 April 2021 (UTC)[reply]

If you have a conventional keyboard, press the "print screen" (or "pr.scr") key. Then you can paste it where you want. Alansplodge (talk) 17:44, 13 April 2021 (UTC)[reply]

Cropping isn't quite the issue :-) ... I am looking for maps the size of about 30 x 40 cm, sometimes probably 40 x 40 cm, and my screen size is a fraction of that. So I'm afraid mere screen capture isn't doing the job. --Ibn Battuta (talk) 17:41, 13 April 2021 (UTC)[reply]

One option is to paste different screenshots together. Alansplodge (talk) 17:46, 13 April 2021 (UTC)[reply]

In my experience that hardly ever gives the same smooth transitions and correct proportions as a genuine picture. And printed at high resolution, that would be visible. So as a poor solution if everything else fails, yes, that's an option... but I would hope there are simply decent, download-able maps out there at this day and age? --Ibn Battuta (talk) 17:58, 13 April 2021 (UTC) PS: Besides, sometimes the colors get mangled up that way, even though I'm not quite sure why. At least that was my experience when screen-capturing and stitching this map years ago; no idea where my file went, but it was far worse quality than the one linked here... --Ibn Battuta (talk) 18:06, 13 April 2021 (UTC) PPS: Just for the record, you may be talking about conventional stand-alone keyboards. All laptop keyboards I've seen in recent years need key combinations to capture screen shots. Or software solutions. Although I believe to remember that even some stand-alone keyboards require those...? Anyways, thanks for the suggestions, I know how to get a screen shot when I want one. :-) --Ibn Battuta (talk) 18:10, 13 April 2021 (UTC)[reply]

WHO Age range classifications

So, there is a "feel good story" sort of viral thing that has been going around the interwebz lately that references a World Health Organization classification of age ranges for various phases of life, and that recently the WHO had adjusted the age ranges as shown below:

0-17 years old: underage
18-65 years old: youth/young people
66-79 years old: middle-aged
80-99 years old: elderly/senior
100+ years old: long-lived elderly

Some examples of the stories that carried the above table, credited (but not directly cited) to the World Health Organization: [1], [2], etc.

I've been looking for the source documents from the WHO with these classifications, but can't find them anywhere. Is anyone else having any more luck? --Jayron 32 16:28, 13 April 2021 (UTC)[reply]

These numbers are plainly wrong. You should have used reliable sources. Ruslik_Zero 17:28, 13 April 2021 (UTC)[reply]

They aren't my numbers, I was doubting their veracity and looking for a source. Thank you for providing one. Problem solved. --Jayron 32 17:45, 13 April 2021 (UTC)[reply]

Resolved

Biologically there is evidence that aging has 3 phases, one of which reaches the person at around age 34, one around age 60, and one at 78.[3] 2601:648:8200:970:0:0:0:1A5F (talk) 05:41, 17 April 2021 (UTC)[reply]

Trying to buy some vitamins

Hi. I am looking for some help and maybe some insight. I am trying to buy some vitamins. I found these: [4]. And I found these: [5]. The first ones cost about $20 for 300 pills. The second ones cost about $15 for only 120 pills. Seems like a big price difference. The products seem to be essentially the same or very similar. Am I missing something? I don't want to throw money away, buying the more expensive ones (the "second ones" at $15 for 120). But, I don't want to end up with "junk", buying the cheaper ones (the "first ones" at $20 for 300). Am I missing anything? Why such a big price discrepancy for nearly identical items? This (the Science Help Desk) seemed the best place to post. But, I am not seeking a "real scientific / technical" answer ... just common sense / consumer perspective. Thanks. 32.209.55.38 (talk) 17:49, 13 April 2021 (UTC)[reply]

The price you pay for a product is only very tangentially related to its value, if at all. Wikipedia has articles on Pricing and Pricing strategies, but what it boils down to is that a company will set the price of a product at the exact point it thinks will maximize its revenue from that product. There is no magic perfect price, and there are lots of ways in which the complexities of human psychology run into pricing and marketing in unusual ways (i.e. Veblen goods, where the demand increases the more expensive it becomes, and Giffen goods, which has a similar effect for different reasons). The basic principle is that there is very little way to tell why two largely identical products will be priced differently, NOR can one tell whether or not one product is better than another (for any given definition of "better") than by price alone. It's... complicated, which can be seen in the article's I have cited. As an example of the insanity of pricing what (is actually) identical products, by visiting only 2-3 stores in my area, I can find a gallon of ordinary, nothing different, cow's milk priced anywhere from $1.39 per gallon to $3.99 per gallon, and these are not "special, organic, wagyu milks" or anything like that. This is your ordinary, run-of-the-mill plain plastic gallon of milk, and the price range for the most expensive gallon is almost triple the least expensive gallon. Pricing is weird. I'm sorry I can't help you figure out which (if either) of your vitamin pills is "better", but price is not necessarily a good way to figure that out. --Jayron 32 18:20, 13 April 2021 (UTC)[reply]

I'd note that the second one actually has 250 for $24.99 so while there is still a price difference (50%), it's not as high as you suggest. Beyond the points Jayron32 made, buying products in smaller is often more expensive for a variety of reasons. Nil Einne (talk) 21:27, 13 April 2021 (UTC)[reply]

Reply to User:Jayron32 and to User:Nil Einne: Thanks, both, for the input and insight. As I was reading the replies, it occurred to me that two other considerations gave me pause (that is, my reluctance to buy the cheaper ones). One: there are quite a few of these products out there; most (if not, all) are priced in line with the higher-priced item. So, it seemed like the cheaper ones were either a great bargain; or some type of rip-off / scam. Two: I thought that maybe the price differential was due to form (soft-gels versus capsules)? But, I can't imagine that that distinction is such a big deal? Thanks. 32.209.55.38 (talk) 23:28, 13 April 2021 (UTC)[reply]

It's also worth noting that many such brands are not produced by companies with a large degree of vertical integration, meaning that many steps of the process of producing the pills might be outsourced. Indeed, MANY modern products are essentially 100% outsourced, where the brand you see on the label means nothing about who produced the product, and where everything from the raw materials to the form factor to the packaging are produced at different companies, and the company who's name and brand are on the label had nothing to do with getting it into your hands. For any given product, there are often far less factories producing that product than there are brands; many brands are produced at the same factory meaning that paying extra for a specific brand name is literally just paying for the name; the product is identical to a less expensive alternative. This is not always true, and there's no guarantee that it is true for your specific vitamins, but it is often enough true due to the economics of supply chains and production; it is simply cheaper for companies to outsource most steps of the production process and simply sell you their name than it is to produce such products themselves. Famously, something like 94% of laptop computers are designed by a small number of Taiwan-based companies, and they are all physically built in a small number of factories in mainland China, mostly around Guangdong. A company you've never heard of, like Compal Electronics or Quanta Computer, likely made the computer you're working on now, regardless of its brand, and it was likely designed and made to be functionally identical (other than certain inconsequential aesthetic elements) to computers priced at vastly different price points. Many, many products in the modern world work this way. This is called white label production and it happens in many industries, often without any obvious way of telling. Another one that comes to mind is liquor; while many companies still produce in house, you'd be surprised how many brands don't anymore, even legacy brands. Diageo owns a number of famous and well-known liquor brands, and much of their production has been shifted to a single distiller, Midwest Grain Products. I could keep going on and on, but suffice it to say that the economics of this is complex. --Jayron 32 11:32, 14 April 2021 (UTC)[reply]

Poorly sourced and off topic medical advice when such medical advice was not even solicited

~~People who take vitamins die sooner. AboutFace 22 (talk) 20:45, 14 April 2021 (UTC)~~[reply]

Please don't make blanket statements, especially health related advice like that, without even bothering to do a citation. --OuroborosCobra (talk) 21:31, 14 April 2021 (UTC)[reply]

If you've got any concerns about vitamins, see your doctor. ←Baseball Bugs ^{What's up,
Doc?} carrots→ 22:02, 14 April 2021 (UTC)[reply]

"Vitamins and Supplements May Lead to Earlier Death," Life Sciences[6]. It's been know for 40+ years AboutFace 22 (talk) 23:25, 14 April 2021 (UTC)[reply]

Please note that the article you quote also states "Both studies showed an association, not a cause-and-effect link.". and "Part of the reason ... may be that taking vitamins or supplements that include more iron or copper than the body needs are harmful for health,... though more work is needed to show this."

note: Emphasis mine and I tried to shorten the quoted text without altering its meaning Rmvandijk (talk) 09:22, 15 April 2021 (UTC)[reply]

Well, AboutFace 22's initial summary, although without a citation, sounds quite correct regarding the article: "People who take vitamins die sooner" = no cause-and-effect link, but an association. Nonetheless good point to stress this fact to readers... :-) --Ibn Battuta (talk) 11:46, 15 April 2021 (UTC)[reply]

Small, because we are going off-topic; The article does say that, but the research they base it on is more cautious. As an analogy, people who take hay fever medication probably suffer more from pollen ^{[citation needed]}. Saying that people who take hay fever medication have runny noses more often is a correct but useless association.

I think it is an important issue. I see even here there is a fog in the answers. I would like to tell you a story without giving any references. It is too bothersome to look for them. Strictly speaking the statement "people who take vitamins die sooner" is not correct individually. It is a statistical phenomenon. If you take two groups of people, let say 1000 strong, give one of them vitamins and leave the other one without, you will find after some years that the mortality in the first group is higher. Why. About 50 years ago one brilliant mind decided to try to treat cancer patients with vitamins. Their cancers accelerated and they ALL dies sooner. The experiment was stopped. So, the reasonable explanation why the 1000 strong group with vitamins had higher mortality is that some of them had occult malignancies. Malignancies feed on vitamins (it has been proven) and the cancers accelerate. It has nothing to do with any impurities in the vitamins. There is another sobering fact associated with it. As one physician said: "vitamins cannot make healthy person healthier," and this is true. Obviously there are special situations: Scurvy [7], Vit 12 deficiency that leads to Megaloblastic anemia[8], etc. For that you should talk to your doctor. :-) AboutFace 22 (talk) 14:32, 15 April 2021 (UTC)[reply]

Sorry, I'm afraid that isn't good enough. A half-remembered story about a "brilliant mind" is not something you should be sharing without some way for people to follow up on your story and read about it for themselves. This is the reference desk it is not the "stuff I kinda remember desk". Please provide references for further reading, or keep your stories to yourself. --Jayron 32 16:44, 15 April 2021 (UTC)[reply]

Getting back to the start of this thread, I agree with Bugs' earlier response, if worried, ask a doctor! Rmvandijk (talk) 12:08, 15 April 2021 (UTC)[reply]

Well, pricing may be an issue; though pricing also often reflects a value, just not only of the product bought--e.g., fancier stores often cost more rent, more interior design, more hours of sales clerks, maybe even more hours for the cleaning staff etc.; so it's not just about brands or marketing, but also about what is paid for apart from the product (incidentally, in industrialized countries, these are often values provided in the country, hard or impossible to outsource; the product itself may be imported; some consumers then complain about outsourcing, but are unwilling to pay for such nationally provided values in the stores, let alone for costlier national production, etc. ...).

That being said, the original question was whether the two products are different. I'm afraid nobody here will know. But maybe worth mentioning that there can exist differences between food supplements. Iron supplements are known to differ in how well consumers tolerate them (some people throw up when taking certain--usually cheaper--pills). I know anecdotal evidence from a doctor about different absorption rates of magnesium pills (a certain low-priced product with high dosage seems to have, among some patients, a lower absorption rate than a more expensive product with lower dosage). A pharmacist even claimed that some (cheaper) products have supposedly inefficient quality control about their dosage as opposed to the more expensive products from medical products (all of them over-the-counter supplements). No idea if K2 and D3 may have similar issues, but I wouldn't rule it out. The problem is, you're unlikely to find a scientific comparison of just your two choices.

Generally, why would you want to take them? Do you have a medical condition, so is anyone checking if you really need them and how well you absorb them? Or do you just believe that K2/D3 might be beneficial to you, without any medical supervision/indication? You will know that generally, too many (unnecessary) food supplements are taken in many industrialized countries; a healthy diet with vegetables and fruit plus regular time outdoors (when the sun is sufficiently high in the sky, e.g., in winter around noon time) is in most cases all we need. That being said, if you have reason to assume you're lacking important vitamins, consider checking with a doctor to find out if the pills you're taking are actually necessary and sufficient. In the long run, that may be cheaper than economizing on Amazon. --Ibn Battuta (talk) 11:46, 15 April 2021 (UTC)[reply]

Without getting into all that economic theory, I'd just say anything on amazon is likely to be fake or worse. I've been happy buying basic supplements and OTC medicines at Costco. They are so much cheaper than places like drugstores that it's worth some extra travel and so on. For example, I take generic loratidine for seasonal allergies and at Costco it's around 3 cents per pill. The name brand (Claritin) is over 10x as expensive, and even generics are at least 3x as expensive at other places. 2601:648:8200:970:0:0:0:1A5F (talk) 05:46, 17 April 2021 (UTC)[reply]

April 14

COVID-19 Vaccines and Blood Clots

It's been reported that there might be a causal relationship between receiving the Johnson & Johnson and AstraZeneca COVID-19 vaccines and getting blood clots, but the actual incident range of those dying appears to be extremely low - about one in a million (or so). My question is this: What is the expected number of people getting killed from blood clots among every million people? A Quest For Knowledge (talk) 19:36, 14 April 2021 (UTC)[reply]

This article in The Lancet gives stats from Denmark. PaleCloudedWhite (talk) 20:03, 14 April 2021 (UTC)[reply]

From the UK Medicines and Healthcare products Regulatory Agency on 7 April: "By 31 March 20.2 million doses of the COVID-19 Vaccine AstraZeneca had been given in the UK meaning the overall risk of these blood clots is approximately 4 people in a million who receive the vaccine". [9] Alansplodge (talk) 21:58, 14 April 2021 (UTC)[reply]

My understanding of the OP's question is that they are asking for the incidence of blood clot deaths generally, unconnected to Covid vaccinations. PaleCloudedWhite (talk) 22:12, 14 April 2021 (UTC)[reply]

I was about to ask a similar question. Maybe someone can answer both.

I have a friend in his late 60s who I just found out is refusing to be vaccinated. He is a physicist, and like many scientists, he likes to analyze and figure out things rather than believing experts, but feeding him raw statistics works very well.

I want to write up an analysis that compares three things: The current infection rate in Los Angeles County, the current fatality rate among 60 to 69 year olds, and the fatality rate for the vaccines available in LA county. I am hoping to be able to show that, statistically, he is more likely to die from not being vaccinated than from being vaccinated.

I am just starting to research this. Has anyone gathered those numbers with citations? --Guy Macon (talk) 23:51, 14 April 2021 (UTC)[reply]

While this is something that has interested me since the early days of Astra Zenica's in late February/early March since it's true most news reports never seemed to really provide figures or how they were derived at best saying it's higher than expected or within expected, note that the expected frequency of blood clots in the population who've received the vaccine probably isn't as meaningful as it seems. As I understand it, one particular reason why blood clots associated with these vaccines have received attention is because most of them have been specific types of blood clots that are fairly rare compared to other forms of blood clots such deep vein thrombosis. See e.g. what the EMA said [10] or these the news source discussions [11]/[12] [13]. (There's obviously a lot better information on AstraZenica than Johnson and Johnson given as I said earlier there have been significant concern for the former for over a month but it's only recently we heard similar concerns for the latter. Note as some of those sources mention, at least for AstraZenica the most similar condition seems to be Heparin-induced thrombocytopenia and there is a tiny mention of the vaccine in that article.) It's possible you will still see a rise in over numbers of blood clots unless the vaccine is associated with a lower risk of other types, but it's also possible the rise is lost in noise. Maybe most likely is you'll have difficulty calculating a figure useful for comparison as you'd need to take into account differences between the subset of people who've been vaccinated and the general population. Age differences is one obvious difference, but also probably others like pre-existing conditions and existing medication usage, socio-economic status and access to healthcare, possibly even sex differences. (I don't know if there is a sex bias in vaccinations but for Astra Zenica thrombocytopenia and blood clots seem to happen in women a lot more than men as the sources mention. It's still early days for Johnson and Johnson but at per sources [14] all the reported cases were women. But per our article for DVT as an example, frequency is higher in men than women although it depends on age.) Nil Einne (talk) 04:56, 15 April 2021 (UTC)[reply]

I understand your more relevant question about general blood clot occurrence. What I have seen, are articles comparing blood clot occurence among vaccines, e.g., here. Apparently, blood clot occurence for BiontechPfizer and Moderna are not higher-than-expected, so that gives a rough (!) idea about general occurrence. (And it saves you the methodological problems mentioned by Nil Einne: comparing a general population with the sample that gets vaccinated.) I see why you would also want to have general figures, though.

As for the basic question: Do I risk more getting vaccinated than not getting vaccinated? From general media outlets (and an experienced pulmonologist who works with Covid patients at a specialized lung clinic, whom I personally know) I understand that figures exist that, yes, it's still safer to get vaccinated than not, esp. for the elderly. This includes--at least for the elderly--AstraZeneca, given that there are few incidences of older people having problems with the vaccine (BTW: no men above 60, to my knowledge). I understand that this is what your physicist will not believe (relying on experts' expertise), yet I thought I'd mention that at least others have done those stats already. :-) Like, you, I'd wish though that general media outlets would simply publish the figures... --Ibn Battuta (talk) 07:37, 15 April 2021 (UTC)[reply]

It doesn't have to be general media outlets. I feel that the manufacturers ought to make the data publicly available that they provide to health authorities, and that health authorities have a responsibility to publish the arguments, including hypothesis testing with regard to safety and efficacy, that lead to their recommendations, and make them available to public scrutiny. A problem in convincing someone who is science-savvy of accepting the risk because of the greater benefit is that they have no influence over the risk of a thrombotic event following vaccination, whereas they have a great deal of influence, through their behaviour, on the risk of contracting COVID-19. So comparing the risk of vaccination with the risk of contracting COVID-19 and falling critically ill, if the latter is based on the rates among the general, possibly not sufficiently cautious population, may not be entirely convincing. There is another issue, that of making rational decisions given existing non-null risks – it is not rational to avoid something beneficial because of a small risk if something less beneficial with a higher risk is gladly accepted. I have heard it said that for someone over 40 the incidence rate of life-threatening thrombosis following a long-distance flight is higher than the reported rate following COVID-19 vaccination among younger women. However, I did not find citable incidence rates in the literature. --Lambiam 10:06, 15 April 2021 (UTC)[reply]

@Guy Macon: As I understand, you would like to show whether P(dying from Covid19|not vaccinated) > P(dying from Covid19|vaccinated) + P(dying from vaccine side-effects|vaccinated) for a given age group and geographical location. (Note that this excludes non-fatal effects from the computation, which might be too simplistic.)

The historical attack rate for LA (i.e. what fraction of the population has been infected) could probably be found on the official websites, but obviously this will not tell you the prospective attack rate (what fraction of the population will be infected in the future), and it is the latter that matters for the probability computation. Of course, there is a whole host of prisoner's dilemna considerations; if your friend is afraid of vaccination, they probably still want everyone else to get vaccinated so that the attack rate plummets and they are safe without getting the vaccine themselves (see: mumps resurgence in recent years, Herd immunity#Free riding, etc. etc.).

The IFR (infection fatality rate, i.e. P(dying|infected)) for a male between 65 and 70 is about 2% (?) from this paper (if you want the exact number, you probably have to look at the supplementary material, I eyeballed the figure but it's a log scale so all I can say for sure is that it is above 1% and below 10%).

The probability of dying of Covid19 when vaccinated is unknown, and cannot be known with the clinical trial data because the trial sizes were not chosen for that (read the "double zero" paragraph). It seems reasonable (in a null-hypothesis sense) to assume that deaths are cut by about as much as symptomatic infections are (which is around 60 to 90% depending on which vaccine, risk profile etc. etc.), but it could be either much better (if vaccination decreases the severity of symptoms about the same for everyone, those who risk to die have the most marginal benefit) or much worse (if vaccination either prevents infection entirely or fails altogether, it tends to fail exactly on people who are at a higher risk to die).

For blood clots I am pretty sure the numbers are too low to be able to give a precise number. This general news article tends to hover at 0.001% or less of "serious harm" (not necessarily death, so not directly comparable to the covid IFR) but it lacks real sources. Tigraan^{Click here to contact me} 09:33, 15 April 2021 (UTC)[reply]

I've only done a quick "back of the napkin" calculation, but based on 6 cases of clotting for the J&J vaccine out of about 7 million vaccinated in the United States, that comes to 8.5*10^-5% chance of having the blood clot complication. That's assuming that we have actual good data on the number of people having clotting complications, and that 100% of them were actually caused by the vaccine, and not what would already be generally expected for that many people (since I don't have that data). By contrast, with 564402 deaths out of 31421360 cases according toe John's Hopkins, that's a fatality rate of about 1.8%. So, if you are infected with SARS-CoV-2, that's 1.8% chance of dying (ignoring factors like age, for the purposes of this napkin calculation). If you get the J&J vaccine, that's 8.5*10^-5% chance of getting a blood clot. That's worst case, assuming all of these were caused by the vaccine. That means, worst case, you are ~21000 times more likely to die of COVID19 if you are infected with the virus than you are to get a blood clot complication if you take the J&J vaccine. Not die from the vaccine, just clotting complication (which can be life threatening, of course). Given those odds, where I'm 21000 times more at risk of dying from the virus than I am of even having a blood clot from the vaccine that protects me from the virus, it's easy to see what I would choose to do. --OuroborosCobra (talk) 19:20, 15 April 2021 (UTC)[reply]

For a comparison of fatality risks based on this calculation, you have to multiply the number ~21000 by the probability of becoming infected. For someone who is extremely careful, that will bring down the ratio considerably, although most likely not into the ~1 ballpark. --Lambiam 10:03, 18 April 2021 (UTC)[reply]

This is likely to undercount the true incidence rate. First, roughly half of J&J doses were given in the last two weeks, and only by raising this issue will we get a fuller accounting of the issue. Second, the vaccine is similar to the Oxford one, whose clotting problem was also at first dismissed. Now we know at least 222 cases in Europe, or they say 1 in 100,000 vaccinations. Imagine Reason (talk) 19:26, 15 April 2021 (UTC)[reply]

I just heard on Radio 4's Inside Science programme that the blood clot complications associated with the AstraZeneca vaccine have, so far, showed up between 5 and 28 days after vaccination. PaleCloudedWhite (talk) 20:30, 15 April 2021 (UTC)[reply]

In this study https://www.bbc.com/news/health-56760163, they compare cerebral sinus vein thrombosis (CSVT) blood clot who develop this type of blood clot within 2 weeks of vaccination(Pfizer or Moderna) or 2 weeks of being diagnosed with COVID. In this article they say for COVID cases there were 39 per million (so 3.9 per 100,000) and the vaccinated group is 8 to 10 times less (0.4 per 100000). AstraZenica was not in this study so can't compare directly. But the European Medical Agency say there were 5 in a million (0.5 per 100000) of a certain type of CSVT. Dja1979 (talk) 21:46, 15 April 2021 (UTC)[reply]

April 15

Weak charge

I saw the following file: https://commons.wikimedia.org/wiki/File:QCD.svg I made a three-dimensional version of it in geogebra.org: https://www.geogebra.org/classic/wzjdbwhs where the original image is a blue plane. It occurred to me to make a similar scheme for the weak interaction: https://www.geogebra.org/m/cqgjvzes where v and w are generators of the group SU(2). Question: is it correct that v and w are "weak charges", but T=(w-v)/2 (just as isospin is 1/2 of the difference in the number of quarks)? --YushinSasha (talk) 16:40, 15 April 2021 (UTC)[reply]

Where do birds get fur for nesting materials?

I watched a YouTube video where a bird plucked fur from a sleepy fox. My impression was that it didn't hurt the fox enough to keep it from falling asleep, but I can't imagine it helping the fox--despite commenters claiming that the fox would need to shed fur to change seasons--since pulling out hair damages hair follicles. But how common is this behavior and is it the main source of fur in bird nests? Thank you. Imagine Reason (talk) 19:24, 15 April 2021 (UTC)[reply]

Animals shed fur. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:01, 15 April 2021 (UTC)[reply]

That's what I thought, but do birds really go around looking at the ground for fur? Would the fur stand out from the other stuff like vegetation?

Animals typically rub against tree trucks and leave fur behind. Abductive (reasoning) 22:51, 15 April 2021 (UTC)[reply]

Carcases. Greglocock (talk) 08:14, 16 April 2021 (UTC)[reply]

They also use dust bunnies which can form in natural surroundings - not just under your sofa. 41.165.67.114 (talk) 10:26, 16 April 2021 (UTC)[reply]

Thus proving that Wikipedia has an article on pretty much everything and that requiring admin candidates to find topics and create articles about them instead of improving exsisting articles is stupid. --Guy Macon (talk) 17:30, 17 April 2021 (UTC)[reply]

Was the bird a crow/raven/magpie? They are known for plucking fur/feathers from the tails and backsides of predators. I think it's more to piss them off and make them leave than to gather nesting material in any significant amount. Sometimes you'll get two or three of them working together. One plucks, the predator turns around and chases the crow, another crow then uses the opportunity to scoot up behind and pluck. Predator chases the second crow, third bird scoots up behind and plucks. Repeat until the predator has had enough. Lesson in why you don't try to hunt prey that's smarter than you? --Iloveparrots (talk) 13:10, 16 April 2021 (UTC)[reply]

Nope, it was a titmouse. [15] Imagine what bigger birds would be willing to do. Imagine Reason (talk) 22:49, 16 April 2021 (UTC)[reply]

Seems to be fairly common. [16] [17] And this one is definitely not mutually beneficial. [18] Imagine Reason (talk) 12:11, 18 April 2021 (UTC)[reply]

April 17

How do they make sure radio waves won't overlap each other?

We watch Televising by grabbing radio waves that carry a video signal representing moving images, along with a synchronized audio channel. How do they make sure this radio waves won't overlap each other? Rizosome (talk) 17:14, 17 April 2021 (UTC)[reply]

Three answers, depending on what you mean by "overlap";

If you are in a room with two light bulbs, how do you make sure the light waves won't overlap each other?
Different TV and radio stations are on different frequencies, and (in the US) the FCC makes sure that they don't interfere with each others signals on a particular frequency.
See Television transmitter#Combining aural and visual signals for analog TV. With digital TV it's all bits and the computer in the TV figures out which bits are which.

--Guy Macon (talk) 17:26, 17 April 2021 (UTC)[reply]

Its actually incredibly complex, there is so much engineering going on behind the scenes it's unreal. See radio resource management and the plethora of techniques listed that are used to prevent co-channel interference. Jules (Mrjulesd) 17:49, 17 April 2021 (UTC)[reply]

This specific case showing how politics can come into it may be of interest. --184.147.181.129 (talk) 06:44, 18 April 2021 (UTC)[reply]

Regarding radio, if you've ever had your car radio on when you were close to a broadcasting antenna, you might observe that it overwhelms every channel on your dial. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:24, 18 April 2021 (UTC)[reply]

That's because the signal is strong enough to bypass the antenna circuit and begin to drive the speaker circuit directly. The purpose of the antenna circuit is to amplify a specific signal and send that amplified signal to your speakers. If the signal in the air is already stronger than the amplified signal from the antenna circuit, then it will be broadcast instead of your antenna signal. This is more pronounced with AM radio than with FM radio; indeed, with AM radio, you can build a simple receiver without a battery; if you're close to the transmitter it will broadcast the signal without any external power source at all; the RF signal is sufficient to drive a small speaker itself. This page describes building simple radio receivers that don't require any power source. --Jayron 32 14:05, 19 April 2021 (UTC)[reply]

For radio waves in vacuum, or air, or on the surface of metal, or in common insulators, the response is linear so that the superposition principle applies. This means that the waves can be separated out again and can pass through each other without affecting each other. Some materials are non-linear. (see Nonlinear optics) These include semiconductors with junctions or some kinds of crystals. In these the waves can mix to make difference and sum outputs, and also harmonics. But the TV will make sure that these are only used by design and not by mistake. Baseball Bugs' example will be due to a non-linearity in the first stage of the receiver that is loaded beyond its design limit. Graeme Bartlett (talk) 12:47, 19 April 2021 (UTC)[reply]

April 18

Are there any biological advantage behind males incapable of reaching multiple orgasms like females?

Are there any biological advantage behind males incapable of reaching multiple orgasms like females? Rizosome (talk) 16:06, 18 April 2021 (UTC)[reply]

The short answer is probably conservation of energy, but men are actually capable of multiple orgasms.[19] See Orgasm#Subsequent and multiple orgasms. nagualdesign 18:42, 18 April 2021 (UTC)[reply]

The obvious answer is that the men would never get any work done, and everyone would starve. Maybe that's what did in the Neanderthals. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:49, 19 April 2021 (UTC)[reply]

I didn't understand this part "men would never get any work done". What do you mean by that? Rizosome (talk) 18:59, 19 April 2021 (UTC)[reply]

Two choices: (1) get to work; or (2) get another orgasm. Which one would you opt for? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:07, 19 April 2021 (UTC)[reply]

Is it possible to create a male calico cat that can reproduce by changing its genes, or would that kill the cat?

Also, if the cat had a baby, would it be female or male?

Answermeplease11 (talk) 20:43, 18 April 2021 (UTC)[reply]

Changing an individual's sex chromosomes from XX to XY is not possible with current technology. Even if it was, one cannot expect the ovary to thereby change into a pair of testicles. --Lambiam 22:33, 18 April 2021 (UTC)[reply]

Lambiam, does this mean that you dont know. And if you dont know, I dont care!

Answermeplease11 (talk) 22:46, 18 April 2021 (UTC) Answermeplease11[reply]

You just convinced me not to put any effort in finding an answer to any future questions you may have. --Lambiam 22:55, 18 April 2021 (UTC)[reply]

Sorry Lambiam, that was a mistake. I would actually like to put in effort for my future questions!

Answermeplease11 (talk) 23:29, 18 April 2021 (UTC)[reply]

Then you won't mind using Google! ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:48, 19 April 2021 (UTC)[reply]

April 19

Over-current in lamp socket?

So, there's one particular lamp socket in my home where the bulb burns out much faster than in any other fixture (and once, when it burned out, it actually made a loud popping noise, almost like a blasting cap) -- which makes me think, could it be that this one fixture draws much more current than the others (despite the bulb being a standard 40-watt one)? What could possibly cause that? 2601:646:8A01:B180:8884:2B54:C0AA:7CD0 (talk) 09:04, 19 April 2021 (UTC)[reply]

I seem to recall that an incandescent bulb would burn twice as bright if there was twice the current. Or maybe 4 times as bright. Abductive (reasoning) 09:26, 19 April 2021 (UTC)[reply]

To get twice the current, you also need twice the voltage. Actually a bit more, as resistance increases with temperature. So that's a bit more than 4 times the power. Brightness will increase stronger than power, as there'll be more visible light compared to infrared. Temperature will rise by over 40%, which means very quick failure. PiusImpavidus (talk) 18:18, 19 April 2021 (UTC)[reply]

Have you checked the wattage rating of that fixture? Some fittings don't permit much air flow which can result in the bulb overheating.--Shantavira|^{feed me} 11:59, 19 April 2021 (UTC)[reply]

It's a while ago that I used any of those incandescent light bulbs (they've been banned in Europe for quite a while), but I remember that they can fail with a bang – not the kind of bang shattering the glass. I've got no experience with blasting caps, so can't compare, but I think electric blasting caps work the same way as failing incandescant lights. My first guess is that you (or someone else in the house) use the light in that particular socket a bit more than you thought. They usually work for about 1000 hours or so, so the more hours per week it's on, the fewer weeks until it fails. Another possibility is vibration. In any case, the current drawn by the bulb is set by the bulb itself (and the power supply, which is the same for all sockets). The socket should have no influence on the current – and if it has, by having extra resistance, it lowers the current, making the light dim and longer lasting. PiusImpavidus (talk) 18:18, 19 April 2021 (UTC)[reply]

Does it pop while the light is already on, or does it pop the moment you turn the light on? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:27, 19 April 2021 (UTC)[reply]

Is it possible to restore DMX’s dead body?

I came up with this idea a few minutes after I heard that he died, which was about 3 days ago. I think that DMX’s body can be revived with these steps, which can be solved after we know what has happened to his dead body. (Unless his body has been incinerated)

Answermeplease11 (talk) 18:11, 19 April 2021 (UTC)[reply]

@Answermeplease11: Although there have been several instances of people recovering after being declared dead (see Lazarus syndrome), there are no known methods for resurrecting or reanimating deceased humans.

Within hours of an individual being declared clinically dead, vital organs such as their brain and heart begin to fail on a cellular level, known as "molecular death". Beyond this point, it is unlikely that their organs could be procured for transplanting, and absolutely impossible that they could be resuscitated or restored.

The rapper known as DMX was declared dead on April 9, 2021 at the age of 50. Barring a sudden technological breakthrough in artificial intelligence (see Mind uploading) and/or time travel (see Technological resurrection), I am sad to say that it is very unlikely that he could be restored to life by any method. RoxySaunders (talk · contribs) 19:26, 19 April 2021 (UTC)[reply]

@RoxySaunders: you havent told me what happened to DMX’s dead body. I would still like know what happened to it, even if want to restore the body. Just please, tell me what happened to it, then I can come up with my solution. (I will possibly be well known in the future for coming up with strategies and solutions)

Answermeplease11 (talk) 20:34, 19 April 2021 (UTC)[reply]

At the moment, at least, his Findagrave entry says "burial details unknown".[20] ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:02, 19 April 2021 (UTC)[reply]

@Answermeplease11: I do not know. The exact state of Mr. Simmons' remains (embalming, cremation, burial, etc.) is a private matter which has not been reported by any media sources. His family have requested privacy in their time of grief, so it would be inappropriate for me to speculate.

While the Reference Desk is not a credible fount for legal or medical advice, I would strongly advise against any futile attempt to steal and resurrect the body of any deceased individual against their wishes. Yours truly, RoxySaunders (talk · contribs) 21:03, 19 April 2021 (UTC)[reply]

@RoxySaunders:, I dont want to steal the body! I just want to call their family, just to ask them if his body can be restored. If they say no, I dont care. But at least he has kids which will continue his legacy! (And learn not to take drugs)

Answermeplease11 (talk) 21:17, 19 April 2021 (UTC)[reply]

You're wandering into inappropriate territory. You had best close out this section. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:26, 19 April 2021 (UTC)[reply]

Sorry, @Baseball Bugs:, just got stuck in a thought. But was my thought a bad one, or a good one?

Answermeplease11 (talk) 21:30, 19 April 2021 (UTC) Answermeplease11[reply]