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April 6

April 8

Superfluids

Why can't the heavier noble gases (neon, argon, etc.) go superfluid at low temperature like helium? Double sharp (talk) 14:17, 8 April 2021 (UTC)[reply]

Superfluidity is a quantum effect caused by the fact that bosons can occupy simultaneous quantum states while fermions cannot. So, you need two things to make a superfluid 1) a boson which 2) has a relatively small number of possible quantum states. Atomic helium-4 (and also dimeric helium-3 and atomic lithium-6) meet both of those conditions. Larger noble gases, like neon and argon, are likely lacking in one or the other things: either they are not bosons (i.e. they have a net half-integer quantum spin, making them fermions) or they have too many sub-particles, meaning the number of quantum states that each individual atom can occupy is so large that the ensemble of atoms cannot "line-up" in the same quantum state necessary for superfluidity. --Jayron 32 14:40, 8 April 2021 (UTC)[reply]

Each noble gas has a stable boson as its most abundant isotope. One of the most commonly used atoms for forming a Bose–Einstein condensate is rubidium-87, so larger nuclei can achieve a large occupation number in the ground state. Any of the noble gases should be able to form a superfluid, if only they were fluid at the relevant temperature. --Amble (talk) 15:25, 8 April 2021 (UTC)[reply]

Good point. Thanks for the correction. --Jayron 32 15:41, 8 April 2021 (UTC)[reply]

Helium is special because it remains a liquid all the way to absolute zero. (As long as the pressure isn't too high; it can freeze at higher pressure). The other noble gases only have a liquid state within a range of temperatures. Below that line, regardless of pressure, they form a solid. They don't go superfluid because they aren't fluid at the relevant temperatures. --Amble (talk) 14:55, 8 April 2021 (UTC)[reply]

LOL, now I feel stupid for missing that. Thanks to both of you for the answers. Double sharp (talk) 15:06, 8 April 2021 (UTC)[reply]

Once you start thinking about the "super" part, it's easy to forget about the "fluid". --Amble (talk) 15:26, 8 April 2021 (UTC)[reply]

Could they form a supersolid, then? I'm a little unclear on just how those are supposed to behave. --Trovatore (talk) 00:57, 10 April 2021 (UTC)[reply]

I don't know. Just from the article, the examples of supersolidity are in BEC gases, not natural crystals. --Amble (talk) 14:33, 11 April 2021 (UTC)[reply]

Can a classical crystal become a Bose–Einstein condensate when sufficiently cooled? Our article treats the case of ideal gases and weakly interacting particles (I assume this means there's limited interaction, not that the interaction is via the weak force), but doesn't really say what happens for highly interacting particles (maybe the theory becomes intractable?). --Trovatore (talk) 18:23, 14 April 2021 (UTC)[reply]

If a doctor does a perineal surgery/incision on a man by hand, just how easy would it be for them to subsequently access this man's prostate?

If a doctor does a perineal surgery/incision on a man by hand, just how easy would it be for them to subsequently access this man's prostate without the help of any robots or anything like that? Futurist110 (talk) 21:45, 8 April 2021 (UTC)[reply]

This again? --Jayron 32 13:52, 9 April 2021 (UTC)[reply]

This does not involve reproduction. The prostate is not a reproductive organ. Or am I not allowed to ask any questions about surgery in general here? Because I thought that the prohibition was limited to questions of a reproductive nature. Futurist110 (talk) 20:32, 9 April 2021 (UTC)[reply]

You must know that this is similar in theme, seeing as the prostate is part of the male reproductive system. This is not dissimilar from your constant line of questions about vasectomies, for example. Why do you feel the need to ask questions on this theme in the first place? --OuroborosCobra (talk) 21:49, 9 April 2021 (UTC)[reply]

Sheer curiosity. Or is that not an acceptable reason? Futurist110 (talk) 00:02, 10 April 2021 (UTC)[reply]

If you were to go to medical school and study urology, it might well answer your questions now and in future. ←Baseball Bugs ^{What's up, Doc?} carrots→ 09:35, 10 April 2021 (UTC)[reply]

"The prostate is a part of the male reproductive system". [1] Alansplodge (talk) 21:52, 9 April 2021 (UTC)[reply]

April 9

Does women's hair naturally/biologically grow faster than men's hair?

Rather unusual question, but does women's hair (on the top of their heads) naturally/biologically grow faster than men's hair or do they grow at about the same rates and women on average simply cut their hair less? Futurist110 (talk) 20:34, 9 April 2021 (UTC)[reply]

I know that men are more hirsute in general in regards to the rest of their bodies, but I was wondering if the opposite effect existed for hair on the top of one's head–excluding male pattern baldness, of course, which would make this comparison way too easy! Futurist110 (talk) 20:35, 9 April 2021 (UTC)[reply]

According to this "medically reviewed" article, it's the other way around; "Male hair grows faster than female hair".

However, according to this article citing this research; "The hair growth rate of the male participants didn't significantly differ from that found for women". Alansplodge (talk) 21:42, 9 April 2021 (UTC)[reply]

April 10

What's the explanation for 10 milion colours?

If the visible light is between 380-750 nm of wavelength, then I'd expected to have 370 colours (each colour for 1 wavelength), but I saw that scientists say there are around 10 million colours. What's the explanation for that? --ThePupil (talk) 04:13, 10 April 2021 (UTC)[reply]

Light is not quantized by the nanometer, that's an arbitrary human unit. We can distinguish colors when presented side by side, testing shows that we can perceive about 10 million such distinctions. See Color vision. Abductive (reasoning) 05:50, 10 April 2021 (UTC)[reply]

I'm old enough that when I learned about wavelengths of light, they were customarily measured in angstroms. Should I have expected 3,700 distinguishable colors to exist?

Anyway, consider also that the light from a particular object will typically consist of a range or mixture of wavelengths, but we still see it as one color. Colors based on a single frequency of light are not the only kind we can distinguish. --184.147.181.129 (talk) 06:04, 10 April 2021 (UTC)[reply]

Indeed, light "of wavelength between 380 and 750 nm (3800 to 7500 Å)" is pure monochromatic light. The human colour perception system can only distinguish a few hundred spectral colours standardized at a uniform brightness. --Lambiam 12:08, 10 April 2021 (UTC)[reply]

You may be interested in All the Colors We Cannot See - Tetrachromacy in Humans. Alansplodge (talk) 15:05, 10 April 2021 (UTC)[reply]
" light "of wavelength between 380 and 750 nm (3800 to 7500 Å)" is pure monochromatic light." Erm, no. That's in fact pretty much the entire visible spectrum, nowhere near monochromatic. Actual monochromatic light will have a range of maybe 10 nm, depending on the source. Fgf10 (talk) 18:35, 10 April 2021 (UTC)[reply]

I think Lambiam meant "of any one wavelength between...". --184.147.181.129 (talk) 20:33, 10 April 2021 (UTC)[reply]
Right-o, meant to correspond to the parenthesis "(each colour [of 370 colours] for 1 wavelength [between 380–750 nm])" in the original question, which clearly reveals that the question is based on the premise that all visible light has a specific wavelength, just like any person between the ages of 18 and 20 has a specific age. The light of extra-spectral colours, such as pink and magenta, does not have "a wavelength", so when any (visible) light is specified as being "of wavelength", it implies (to me) it is monochromatic light. --Lambiam 11:57, 11 April 2021 (UTC)[reply]

An interesting Covid vaccine question

I had another engineer ask me an interesting question today.

mRNA causes the cells to build a foreign protein. The protein molecules cause an immune response. Later the immune system identifies and destroys the actual pathogen. So, does the mRNA keep building the protein forever? Or is the mRNA "used up" and you only get as many protein molecules as you got mRNA molecules? Or is it somewhere between with one mRNA building more than one protein but eventually getting "worn out" instead of producing proteins forever? I tried to figure this out from reading our RNA vaccine article but it wasn't clear to me. --Guy Macon (talk) 21:39, 10 April 2021 (UTC)[reply]

According to Messenger RNA#Degradation, the mRNA lasts from a few minutes to several days, so your final supposition appears to be correct.-gadfium 21:46, 10 April 2021 (UTC)[reply]

mRNA is also degraded when processed (it loses some A codons at the end, similar to how DNA loses telomeres). This site has a discussion of the full mRNA sequence of the BioNTech/Pfizer vaccine - it makes for fascinating reading (at least for geeks like me). --Stephan Schulz (talk) 11:43, 12 April 2021 (UTC)[reply]

April 11

Domestic heat recovery systems

Why do some domestic heat recovery systems only have grilles in the rooms with moisture like the kitchen and bathroom? Aren’t they meant to pump fresh air into dry rooms like the bedroom too? 2A02:C7F:EA3E:8000:D046:E85D:FE32:6A85 (talk) 01:30, 11 April 2021 (UTC)[reply]

Some of those grills might just be ventilators connecting to the outside, to let fresh air in. But in that case it is not a "domestic heat recovery system". These would have to be modified for that situation. Air can circulate under doors to move between rooms to find the return path. Graeme Bartlett (talk) 07:39, 11 April 2021 (UTC)[reply]

Even if the grills are connected to a heat recovery system? How does a system like that allow air to move under doors? 2A02:C7F:EA3E:8000:1509:8071:E91F:B94A (talk) 09:26, 11 April 2021 (UTC)[reply]

Are you saying that when the door is closed, there is no flow of air in the bedroom? 11:15, 11 April 2021 (UTC)

I assume that you are talking about Heat recovery ventilation. In bathrooms and in kitchens it is important to remove excess humidity and fumes. Graeme Bartlett (talk) 23:25, 12 April 2021 (UTC)[reply]

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: [2], [3], 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

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]

~~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]

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". [7] 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 [8] or these the news source discussions [9]/[10] [11]. (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 [12] 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]

April 15

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 I am just starting to research this. Has anyone gathered those numbers with citations? --[[User:Guy Macon|Guy Macon]] ([[User talk:Guy Macon|talk]]) 23:51, 14 April 2021 (UTC)
 :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 [//www.ema.europa.eu/en/news/astrazenecas-covid-19-vaccine-ema-finds-possible-link-very-rare-cases-unusual-blood-clots-low-blood] or these the news source discussions [//www.cidrap.umn.edu/news-perspective/2021/04/studies-suggest-link-between-blood-clots-astrazeneca-covid-vaccine]/[//www.bmj.com/content/373/bmj.n954]  [//abc7news.com/covid-19-vaccine-side-effects-cdc/10512795/]. (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 [//www.bbc.com/news/world-us-canada-56733715] 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.) [[User:Nil Einne|Nil Einne]] ([[User talk:Nil Einne|talk]]) 04:56, 15 April 2021 (UTC)
+::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., [https://www.statnews.com/2021/04/13/researchers-search-for-answers-in-puzzle-of-blood-clots-and-covid-vaccines-and-see-some-clues/ 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 [[pulmonology|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... --[[User:Ibn Battuta|Ibn Battuta]] ([[User talk:Ibn Battuta|talk]]) 07:37, 15 April 2021 (UTC)
 = April 15 =