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July 23

Biochemistry of allergies

Why is it that life threatening allergies involving the respiratory or cardiovascular system is rare compared to Reactions involving the skin and/or digestive tract? Is it just because these areas are more exposed to allergens or is there more protecting the respiratory and cardiovascular systems? Why do many food allergies for example show skin and digestive symptoms but rarely the more life threatening symptoms as an example? Clover345 (talk) 11:43, 23 July 2020 (UTC)[reply]

Anaphylaxis, a potentially life-threatening allergic reaction if not timely and appropriately treated, often involves serious respiratory or cardiovascular symptoms. Together these account for most of the lethal cases. --Lambiam 12:59, 23 July 2020 (UTC)[reply]

Also, don't confuse the popular term "allergy", meaning "any adverse reaction to something" and an actual allergy, which is a much more restrictive process in the body. To be an actual honest-to-god allergy, it must be initiated by an immune system response to something. Some things we call allergies may be more properly called things like Irritant contact dermatitis and Food intolerance. Secondly, MANY allergies cause respiratory problems; especially when the mode of the intaking the allergan involves breathing it in. Atopy, a medical term for a specific class of allergic reactions, includes asthma as a common symptom; indeed of the three main components of atopy (eczema, rhinitis, and asthma); two of them are respiratory related (rhinitis is inflammation of the upper respiratory system (nose and sinuses) and asthma is inflammation of the lower respiratory system (lungs)). --Jayron 32 15:34, 23 July 2020 (UTC)[reply]

But I thought anaphylaxis is quite rare even amongst people with allergies? Clover345 (talk) 16:19, 23 July 2020 (UTC)[reply]

The Wikipedia article on anaphylaxis has prevalence figures right in the lead. You're allowed to draw your own conclusions as to the tolerances of a concept like "rareness", but the information necessary to do so is already in the article you were referred to by Lambiam, and rather prominently. --Jayron 32 16:21, 23 July 2020 (UTC)[reply]

Yes but the article doesn’t answer my original question. Clover345 (talk) 17:10, 23 July 2020 (UTC)[reply]

Your original question contains a presupposition that is not currently shown to be true. That is, when you state "Why is it that life threatening allergies involving the respiratory or cardiovascular system is rare compared to Reactions involving the skin and/or digestive tract?" you have not yet established that "life threatening allergies involving the respiratory or cardiovascular system is rare compared to Reactions involving the skin and/or digestive tract.". We can't answer "why" on a concept that is not yet itself shown to be commonly shown to be true. What is even your reason for supposing that? --Jayron 32 17:15, 23 July 2020 (UTC)[reply]

Ok I shall rephrase the question then - why are cardiovascular and respiratory symptoms less common than symptoms involving other organ systems in people with allergies? Clover345 (talk) 17:34, 23 July 2020 (UTC)[reply]

OK, I shall rephrase my question then - Are they? --Jayron 32 17:53, 23 July 2020 (UTC)[reply]

And before you go digging, Allergic rhinitis is the most common allergy symptom, bar none. Unless you're prepared to argue that respiration doesn't involve the upper respiratory tract, I can't see how an actual honest-to-god respiratory symptom being the most prevalent allergy symptom can do anything but refute your assertion that respiratory symptoms are somehow less prevalent than other symptoms. --Jayron 32 17:56, 23 July 2020 (UTC)[reply]

That seems to be true which deepens my curiosity. It seems upper respiratory symptoms are more common than lower respiratory symptoms or cardiovascular symptoms. Why is this? Clover345 (talk) 20:40, 23 July 2020 (UTC)[reply]

If I were to speculate, it's because allergans have to actually get into the body, so I would suspect the most prevalent allergan responses would be those at the modes of entry to the body: upper respiratory, skin, and digestion. Thus, rhinitis, eczema, and food allergies being among the three most common allergic reactions. --Jayron 32 10:35, 24 July 2020 (UTC)[reply]

Interesting and that would be my speculation too. Then this raises the question of why people get skin reactions (for examples hives on the body) with food allergies without necessarily getting symptoms elsewhere. In the case of food, mode of entry is the digestive system. Clover345 (talk) 11:32, 24 July 2020 (UTC)[reply]

Allergic reactions are type II immune responses. The affected tissues will be a result of the properties of the activated immune cells. Different tissues have different sensitivities in part due to a differing resident immune population, the non immune cells controlled or affected by the immune response and differing innervation by nociceptors. The full answer to your question is scientifically unknown however. PainProf (talk) 14:50, 24 July 2020 (UTC) - This made me realise for reasons unknown we don't describe type 1 immunity vs type 2 in any of the major immunity articles. PainProf (talk) 15:13, 24 July 2020 (UTC)[reply]

Inselberges and monadnocks are may not the same thing

I learned from a school textbook of geography that inselberges and monadnocks are not the same thing. I am greatly suprised to see the WP article of inselberg, which says that they are the same thing. Let me illustrate the comparison between inselberges and monadnocks according to the textbook:

Subject	Inselberg	Monadnock
Definition	Hill-looking object located in a desert.	Hill-looking object located in a plain.
Origin	Aerial erosion.	River erosion.
Shape	Slightly circular and steep sides.	Almost circular and not-so-steep sides.

Can someone look into this inselberg–monadnock problem? --Soumya-8974 ^talk _contribs ^subpages 15:28, 23 July 2020 (UTC)[reply]

This is one of the many terms that are used somewhat differently in the US compared with UK (and the rest of Europe). A quick glance through the available books on Google Books shows that some works recognise distinct differences, while others view them as synonyms. The place to raise this is at Talk:Inselberg, where you could open a discussion, but read through all the other discussions that look at this particular issue before doing that. Mikenorton (talk) 16:28, 23 July 2020 (UTC)[reply]

Coutesy link inselbergs and monadnocks — Preceding unsigned comment added by 31.53.187.190 (talk) 08:32, 24 July 2020 (UTC)[reply]

Although "monadnock" redirects to "inselberg", which is the point of the question. Mikenorton (talk) 10:41, 24 July 2020 (UTC)[reply]

July 24

Magnetic generator

This site declares its fuelless generator products for sale. As far as I know this is not possible, violating conservation laws. Do you have any ideas how this can be, or if they are fake pitching? Almuhammedi (talk) 04:47, 24 July 2020 (UTC)[reply]

I think you answered your own question. Ruslik_Zero 05:05, 24 July 2020 (UTC)[reply]

It is indeed possible that this product is for sale. It also has a really cool look, a lot more than an earlier version just a few years ago. I'm afraid that it is even possible some gullible people invest their money in this. This does not violate the law of conservation of money: it just flows from one pocket to another one. --Lambiam 06:55, 24 July 2020 (UTC)[reply]

Remark that they are talking of 'preorder', that they don't expect any money so far and that this generator is one of their 'ongoing projects'. But this way they can collect addresses of people from all over the world that presumably have some bucks to spare and are possibly willing to spend them on silver mines. 2003:F5:6F0C:9500:89C7:4269:E468:97B (talk) 15:09, 24 July 2020 (UTC) Marco PB[reply]

Pre-order may require a small payment. If large number of people pay, they may collect a lot of money! Ruslik_Zero 12:19, 25 July 2020 (UTC)[reply]

So the product works as intended? DMacks (talk) 12:22, 25 July 2020 (UTC)[reply]

Thank you all for sharing ideas. I have already argued using simple modeling and transformation equations to convince my friends who unfortunately didn't accept my analysis and told me that technology has advanced beyond old "traditional" laws. One of them argued the secret lies in the very strong magnet energy. I tried to explain the difference between magnetic stored energy (which I consider it as latent, can be calculated from Maxwell's equations), and the energy transformation here in which the magnet is just like a mediator between motion and electricity. I failed to explain any further, so I came here to understand if I were missing some new physics. I guess I would encourage them to buy and try. Almuhammedi (talk) —Preceding undated comment added 14:27, 25 July 2020 (UTC)[reply]

For energy production, the only relevant new physics is nuclear energy, in which mass as input becomes (usable) energy as output. Other than by mass conversion, the energy output that is available for work, if not zero, is always strictly less than the energy input. The difference is lost as (unusable) heat. The advertized magnetic generator contains a motor, so there will be some friction. See Perpetual motion machine. Is your plan to encourage your friends to lose their money in this scam because it will teach them a lesson? --Lambiam 21:58, 25 July 2020 (UTC)[reply]

July 26

Moon question.

What part of the world sees the moon the least? Or has the hardest time seeing the moon, like if the moon can only be seen down circling the horizon. 166.137.83.64 (talk) 07:35, 26 July 2020 (UTC).[reply]

Perhaps you will want some constraints, eg the moon is invisible inside most caves, and inside many forests. The Aleutian Islands are nearly always covered in cloud, so they cannot see the moon either. Deep valleys would have reduced time of moon in the sky too. The south facing slopes in Antarctica would also get less sun and moonshine. Graeme Bartlett (talk) 07:45, 26 July 2020 (UTC)[reply]

In Graeme's response, for "could" read "cloud". 2A00:23C1:E101:D700:2C7F:D268:D5DE:B039 (talk) 10:48, 26 July 2020 (UTC)[reply]

As the orbit of the Moon is within a few degrees of the ecliptic, it follows that an observer in the Arctic or Antarctic will generally see it lower in the sky than is true for observers elsewhere. However, it would not be a case of "only down circling the horizon"; even at the poles it could be about 28° above the horizon at times, I believe. --174.89.49.204 (talk) 07:53, 26 July 2020 (UTC)[reply]

The angle of the Moon's orbital plane with the Earth's equatorial plane oscillates between about 18.5° and 28.5°, with a period of 18.61 years. Assuming a perfectly spherical ~~cow~~ Earth with no geological, architectural or atmospheric impediments to Moon gazing, the Moon should on the average be visible half the time – but near the Earth's poles a half ~~synodic~~ month of visibility will alternate with a half ~~synodic~~ month of invisibility. --Lambiam 11:28, 26 July 2020 (UTC)[reply]

The question was about different places, not different times. --174.89.49.204 (talk) 22:55, 27 July 2020 (UTC)[reply]
- And my answer was that it is half the time everywhere. --Lambiam 20:50, 29 July 2020 (UTC)[reply]

The extremes are 5.295 degrees plus ecliptic, either north or south. This occurs when Luna is far from Earth, syzygys, solstices or perihelions. Right now ecliptic is 23.438 degrees or less, decreasing slowly so maximum should be 28.733 degrees for the center, almost but not quite 29 degrees for the top and at least a minute of arc or so on top of that for atmospheric refraction. Wider moons but closer to the 4.995 degree minimum shouldn't improve that much if at all. But wait! There's parallax. So subtract about a degree for that and you get about 28 degrees for the top. The tropic of Cancer for moons is about Orlando. No parallax there the rare times you're right under it. Sagittarian Milky Way (talk) 01:22, 27 July 2020 (UTC)[reply]

And I'm wrong of course, the highest Moon center of 1988-2024 or more from the North Pole is 27.92357 degrees September 14, 2006 21:37 Eastern US time or so, but really more cause North Pole weather is usually colder than the Earth average 15 Celsius around the equinoxes which can refract light more. My error is that the North Pole is not the top of the Earth from a Moonar perspective when the Moon is also at almost 29 degrees North. Sagittarian Milky Way (talk) 02:02, 27 July 2020 (UTC)[reply]

Between the 60s and the 2060s exclusive the highest from any pole was 1987-Sep-15 27.9452 degrees. Far out man. Sagittarian Milky Way (talk) 02:53, 27 July 2020 (UTC)[reply]

Why a synodic month? Surely the nodes precess slowly enough that a sidereal month is more relevant here. —Tamfang (talk) 02:28, 27 July 2020 (UTC)[reply]

The fact that the length of a synodic month varies through the year is a giveaway that this is the wrong kind of month here. It should be the kind of month that lasts the period of time between two successive events in which the Moon passes through the Earth's equatorial plane from (say) the southern to the northern sky. Is that an anomalistic month? Or a tropical month? My head also starts spinning. --Lambiam 08:11, 27 July 2020 (UTC)[reply]

It's not one of the major 5 moonths, tropical month should be the long term average. Sagittarian Milky Way (talk) 13:16, 27 July 2020 (UTC)[reply]

If the ascending node is entering the southern hemisphere this moonth will be shorter than tropical, if it's on the other side of the sky it'll be longer. Sagittarian Milky Way (talk) 13:47, 27 July 2020 (UTC)[reply]

Olympus Mons

Would it make sense to have a launch site, maybe even an electromagnetic one, on the peak of Olympus Mons on Mars, to save fuel? Greetings, 2003:C3:EF2A:EC86:C085:C6A3:FBFE:686B (talk) 11:03, 26 July 2020 (UTC)[reply]

To a first approximation, the energy needed to make a given fixed mass escape from a planet is inversely proportional to the distance from the centre of the planet. The height of Olympus Mons is about 0.6% of the radius of Mars, so the saving would be about 0.6%. In practice it should be more for a fuel-driven rocket, since the fuel consumption needed to achieve the same thrust is higher at the surface, and therefore the energy needed in practice is not really inversely proportional. Whether the saving is worth the trouble of having to haul up everything to the high launch site depends on too many factors for a back-of-the-envelope calculation. In SF stories, larger space vessels typically remain in orbit, with smaller shuttles operating between orbit and the surface. The lighter the shuttle, the less interesting such savings. Presumably, most shuttles will operate from launch sites near settlements (operational bases), and other considerations about the most suitable locations for operational bases, such as the local availability of natural resources, may well outweigh considerations of fuel efficiency. Using not the peak but the slope of Olympus Mons for the track of an Electromagnetic Shuttle Launch System (ESLS), on the other hand, seems (IMO) worth serious consideration. I'm too lazy to do the calculation, but I guess one should comfortably be able to reach escape velocity given the track length that is possible. --Lambiam 12:44, 26 July 2020 (UTC)[reply]

Thank you very much! --2003:C3:EF2A:EC86:C085:C6A3:FBFE:686B (talk) 13:28, 26 July 2020 (UTC)[reply]

Another option for non-rocket spacelaunch would be a space elevator. One could be built on Mars with existing materials, as Mars has much lower gravity than Earth. --47.146.63.87 (talk) 06:19, 27 July 2020 (UTC)[reply]

The space elevator should be anchored at the Arean equator, thereby leaving Olympus Mons out of the picture. --Lambiam 07:41, 27 July 2020 (UTC)[reply]

Another thing to keep in mind is the rotational speed of the surface, wich is maximal at the equator, and a "free gift" for launches into equatorial orbits. Olympus Mons is close enough to the equator that that would not probably disqualify it, but it reduces the benefit. --Stephan Schulz (talk) 08:28, 27 July 2020 (UTC)[reply]

And the track of an electromagnetic launch system on the slope of Olympus Mons should use the western side (where East and West are with respect to the directions where the Sun rises and sets on Mars), so as to launch in the easterly direction and add rather than subtract from that free gift. --Lambiam 08:48, 27 July 2020 (UTC)[reply]

July 27

Teeth

Why are teeth so numerous? Why have so many teeth, rather than just two, big, U-shaped teeth? And, what is with them being so maintenance-heavy? Why do they rot so easily? — Preceding unsigned comment added by 2602:252:D14:F900:A5A7:1F:C2F2:B639 (talk) 03:59, 27 July 2020 (UTC)[reply]

Cause our teeth are shit and should've been encased in silicon oxide (we might need to swallow sand occasionally to get enough silicon) but evolution isn't to make life easier, it's the side effect of accidental mutations sometimes getting popular by fertility or even luck and even worse, the logical result is reproducing to death. This is why pigeons are hungry, if there were any more that many would die, if they don't they just fuck till there *are* too many. Just because other lifeforms have silicate shells doesn't mean we'd evolve them too. Sagittarian Milky Way (talk) 05:56, 27 July 2020 (UTC)[reply]

The interrogative adverb "why" has several meanings. See also Teleology in biology and Poor design. If humans had just two, big, U-shaped teeth, they'd have a real problem though, if one broke. You can go on living happily with quite a few fewer teeth. Human teeth have not co-evolved with the typical human diet, which involves much less gnawing and much too much sugary stuff, and thus (without meticulous dental hygiene) much more dental plaque buildup and a happier environment for the bacteria causing tooth decay than when mammal teeth evolved. Here is a link to an article on the topic from the Scientific American. --Lambiam 08:34, 27 July 2020 (UTC)[reply]

According to the link, our current diet is too soft and sugary for our teeth. I would ask "why so soft and sugary?", but it is probably best if I do not ask: I somehow suspect that the [rabbit hole] is very, very deep. 2602:252:D14:F900:4D59:D5D9:8F1C:E9B7 (talk) 21:11, 27 July 2020 (UTC)[reply]

Not really, the answer is "agriculture". Most of what we eat is man-made; we've selectively bred it to be more nutritious and easier to eat. Compare maize or bananas with their wild relatives (the articles have pictures). --47.146.63.87 (talk) 23:25, 28 July 2020 (UTC)[reply]

Might as well ask why we even need teeth. We have blenders. Just turn everything into soup or paste and do away with teeth all together. 97.82.165.112 (talk) 11:15, 27 July 2020 (UTC)[reply]

Also bear in mind that humans need "four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food."--Shantavira|^{feed me} 11:30, 27 July 2020 (UTC)[reply]

We inherited the layout from our primate forbears and so on down the evolutionary chain. Tortoises have two bony ridges that function like the OP's "U-shaped teeth", but lack the ability to chew. [1] Alansplodge (talk) 13:40, 27 July 2020 (UTC)[reply]

Solar Panels

I have heard recently in conversation that Solar Panels being the solution to our future energy problems may be a false economy. I recall the Palm Oil Solution in the late 90’s which has turned from a blessing to a curse and wonder if what I heard is accurate…Google searches seem to provide me with multiple false results. I was told that Solar panels for industrial use, e.g. those use in massive farms to power cities, only last a few years at which point they need to be entirely replaced. The now useless panels can’t be fully recycled or recycled at all and will end up in landfills, bleeding harmful chemicals and causing more damage that what they are supposed to prevent. Is this true? What other solutions are there? The only other I have heard is that of harnessing the power of Ocean waves; yet I have heard very little about this. Why? Why would we take the gargantuan step to move from coal or nuclear power generation to solar, if this is not truly a solution, if we’re going to make the change why not do it properly the first time? What other solutions are there and why are these not being employed? Thanks. — Preceding unsigned comment added by 31.53.187.190 (talk) 12:25, 27 July 2020 (UTC)[reply]

Don't believe every anti-environmental thing without asking physicists or something first (I guess we're probably good enough). If you were Israeli or Palestinian you wouldn't believe every bad thing said about your people without consulting reliable sources would you? That should apply to anything with haters. Sagittarian Milky Way (talk) 13:30, 27 July 2020 (UTC)[reply]

...and that's why I'm asking here. — Preceding unsigned comment added by 31.53.187.190 (talk) 14:22, 27 July 2020 (UTC)[reply]

One excellent source of information on energy is the ... Energy Information Agency, an independent analysis agency under the United States Department of Energy.

Every year they publish an Annual Energy Outlook, including projections about the economic and physical developments for short and long term. "The Annual Energy Outlook presents an assessment by the U.S. Energy Information Administration of the outlook for energy markets through 2050." This is a largely factual assessment.

If you are looking for an introduction to a policy assessment, first you have to decide whose policy opinions you trust. Where do we begin on such a broad topic?

If you are a late-stage learner, we can point you to published books, journals, and scientific reviews. In almost any public library's nonfiction section, you will find a lot of writing on the topic of energy policy.

If you are an early-years student and looking for information, we should point you toward appropriate college-level classwork and the resources therein.

One can pursue many years of full-time education and still only have received a brief introduction to energy and environmental policy. For example, the first- and second-year undergraduates at Stanford might take Sustainable Energy for 9 Billion, ... and if they are interested, they might pursue three more years of undergraduate specialization in the environmental and energy curriculum, and then proceed toward five or six more years in post-graduate research in environmental or energy topics.

The point, though, is that you are not going to find an easy answer to this topic. We cannot and should not summarize it into a sound-bite.

For something a little bit topical, here is a Conversation with Steven Chu: Lessons from the Past and Energy Storage for Deep Renewables Adoption, part of the Precourt Institute for Energy's Global Energy Forum, a "virtual dialogue" filmed in the context of the COVID-19 Pandemic. Steven Chu is a physicist, a Nobel laureate, and served under President Obama as the United States Secretary of Energy. One time he even shot up some atoms with a laser, so this is a guy who doesn't mess around.

Nimur (talk) 16:12, 27 July 2020 (UTC)[reply]

From an economic perspective: Many manufacturers seem to offer a warranty for 20-25 years on panels (normally, that they will still perform at 80% nominal level after that time). For comparison: Normal large power-plants are often designed for a 30 year life span. At the moment, it seems that solar panels are more often replaced because newer generations offer significantly better performance, not because they are "worn out". Any product can be recycled. None can be recycled perfectly. The degree to which they are recycled depends on the economic and regulatory environment. A German research project claimed full-cycle recycling rates (including production waste) of about 95% back in 2010 [2]. --Stephan Schulz (talk) 16:54, 27 July 2020 (UTC)[reply]

Domestic panels have a 20 year 80% warranty typically. In 4 years I have seen no drop off in performance. I also have some 30 year old panels that seem to be about 10% efficient, which may well be what domestic grade was back then. So it would seem that claims of a lifetime of 'a few years' are rather selective at best. Greglocock (talk) 22:33, 27 July 2020 (UTC)[reply]

Solar panels are pretty durable, but large battery storage systems may be more of a problem. 2601:648:8202:96B0:0:0:0:5B74 (talk) 06:03, 28 July 2020 (UTC)[reply]

The Lifespan of Solar Panels quotes a couple of studies which show a long term annual loss of between 0.5% and 0.7%. It also describes the 2010 discovery of a 1946 solar panel (actually a solar globe) which still worked. Alansplodge (talk) 20:14, 28 July 2020 (UTC)[reply]

There are ways other than batteries of storing power. Cool fact: superconducting magnetic energy storage can store electrical power indefinitely, since superconductors have no resistance. The only problem is maintaining the superconductive state. The choice between different methods is an engineering and economic problem. For instance, battery systems are nice for stabilizing electrical grids since they can be discharged at-will; there's no "lag time" like that needed to spin up an electrical generator. --47.146.63.87 (talk) 23:32, 28 July 2020 (UTC)[reply]

July 28

"In the hospital being treated with oxygen for his lungs"

(This is about Herman Cain.[3]) What does that phrase mean? Supplemental oxygen usually doesn't require hospitalization. Plus if he is conscious and able to speak, I figure they'd have him say something to his well-wishers on TV, so it sounds like he's still not in great shape. Could it mean intubation? Hyperbaric oxygen? Or are they just being vague about his condition? Thanks. 2601:648:8202:96B0:0:0:0:5B74 (talk) 05:59, 28 July 2020 (UTC)[reply]

The last sequence of tweets about Cain's condition does not provide enough information to be sure. They go, "But he is still in the hospital being treated with oxygen for his lungs. [...] Re-strengthening the lungs is a long and slow process, and the doctors want to be thorough about it."^[4] The lungs being affected by COVID-19 can lead to acute respiratory distress syndrome, for which hyperbaric oxygen treatment is being used,^[5] and since this would require continued hospitalization, this appears to be a definitely possible explanation. But we can't be sure without further information. --Lambiam 08:56, 28 July 2020 (UTC)[reply]

Thanks, doesn't sound like hyperbaric therapy is usually given 24/7. It's done with a mask on, though. If it's just hyperbaric then from the descriptions I'd expect he is conscious and could smile and wave for a camera, even if he can't talk. Could be be on ECMO? I guess we will just have to wait for updates. 2601:648:8202:96B0:0:0:0:5B74 (talk) 21:35, 28 July 2020 (UTC)[reply]

Given that his death was announced this morning, I'd say his condition 3 days ago was probably not good. --OuroborosCobra (talk) 16:07, 30 July 2020 (UTC)[reply]

Why do they put tubes in you instead of an external mask or dialysis but lung stuff instead of dialysis organs (if alveoli are too fucked to work)?

Maybe there's way too few lung analog of dialysis machines but why not just glue a damn oxygen mask to the patient instead of lubricating a tube down their throat? If the tube machine moves the diaphragm for the patient with pressure cycles then how hard could it be to connect a fighter plane-style mask to it instead? Sagittarian Milky Way (talk) 18:36, 28 July 2020 (UTC)[reply]

I suspect the major reason is that with external positive pressure, you would push all kinds of undesirable material into the lungs - in particular parts of the contents of the stomach, if the patient throws up. Such events almost always lead to (an additional) pneumonia, which is a serious risk for patients (which is a polite way of saying "they die like flies"). Also, as far as I know, "fighter pilot masks" don't use significant (or any) positive pressure, they just provide oxygen and rely on the normal breathing of the pilot to move the breathing gas. --Stephan Schulz (talk) 19:09, 28 July 2020 (UTC)[reply]

Yes, the point is that such machines are needed when the patient cannot breathe alone. Applying pressure externally would probably not bring any air into the lungs because the throat could lock closed with undesirable short term consequences. But perhaps you mean this would quickly free one more bed, wouldn't it?

And sorry but I fail to understand what you mean with the second part of your question '.. or dialysis but lung stuff instead of dialysis organs' 2003:F5:6F0C:9500:2DDB:7E1A:35F8:B774 (talk) 19:18, 28 July 2020 (UTC) Marco PB[reply]

I think the second part may be in some way a question about extracorporeal membrane oxygenation. - Nunh-huh 19:42, 28 July 2020 (UTC)[reply]

I happen to have personal experience with this. I recently spent 6 days on a respirator. The first 4 days I was kept unconscious. Then 2 days on the respirator. Then 4 days on Non-invasive ventilation. Then another 2 days with just supplemental oxygen. --Guy Macon (talk) 19:45, 28 July 2020 (UTC)[reply]

Why'd they wake you up for only 2 days just to make you uncomfortable? Why not wait till after intubation? Did you catch it while maskless? Sagittarian Milky Way (talk) 21:43, 28 July 2020 (UTC)[reply]

Catch it while maskless? Oh, I get it. You thought I had Covid-19. I had cardiac arrest caused by an undetected electrical problem in my heart. As for why they woke me up, here is how it works. You can breathe on your own for a couple of minutes, then you can't and the respirator takes over. You rest, then do it again. You can lift your arm maybe an inch, then it falls back exhausted. You rest, then do it again. That's your job. Keep it up and eventually you can roll on your side. More exercise and eventually you can sit upright for a whole minute. Skipping a bunch of steps, eventually you can walk. They wake you up so you can start working at getting your strength back. --Guy Macon (talk) 23:02, 28 July 2020 (UTC)[reply]

So that's what it's called, extracorporeal membrane oxygenation. So probably a reason why that's a laster resort than intubation is that they apparently have to stab the aorta and vena cava or something, in dialysis you don't have to clean a gallon and change of blood before the patient suffocates so it can be slower and you can stab less extreme locations so it's more routine. Sagittarian Milky Way (talk) 21:43, 28 July 2020 (UTC)[reply]

Usually known as its acronym, ECMO. Yes, ventilators are less troublesome and less dangerous, and have been around longer, so they would be the default. - Nunh-huh 22:28, 28 July 2020 (UTC)[reply]

And if you can handle Non-invasive ventilation instead of the tube down your throat, they do that. --Guy Macon (talk) 23:02, 28 July 2020 (UTC)[reply]

"Overall, 19% of hospitalised [COVID-19] patients require non-invasive ventilation, 17% require intensive care, 9% require invasive ventilation, and 2% require extracorporeal membrane oxygenation". BMJ Best Practice Alansplodge (talk) 16:30, 29 July 2020 (UTC)[reply]

Again from personal experience, that non-invasive ventilation was a huge help. I was working really hard at breathing on my own, knowing that doing the breathing exercises the physical therapist gave me was the best way to get out of that hospital room. But my chest muscles got super tired. When that happened, I put the mask back on and the machine did most of the work, pushing air in and pulling it out and giving my muscles time to rest up until I could try again. Plus, I got to do a great Darth Vader impression... :) --Guy Macon (talk) 17:14, 29 July 2020 (UTC)[reply]

July 29

Guillermo Gonzalez (astronomer)

Does Guillermo Gonzalez (astronomer) have a middle name or initial? --Guy Macon (talk) 14:27, 29 July 2020 (UTC)[reply]

I don't think so, no paper by him or about him seems to cite a middle name/initial even if all co-autors/contributors do have one, e.g. here [[6]], and here they state that he has none (or they also found none): "Guillermo Gonzalez, no middle initial, b. 1963" at [[7]]. But I would have expected it, this 'middle name or initial' seems to be a pure US American habit. 2003:F5:6F0C:9500:4070:591A:3CFE:72F (talk) 16:41, 29 July 2020 (UTC) Marco PB[reply]

Thanks! --Guy Macon (talk) 17:07, 29 July 2020 (UTC)[reply]

Tornadoes

Which area of the USA sees the most tornado warnings per year? I mean a single location, not a state or county. According to this Jackson, Mississippi averages 2.5 warnings a day. That can't be realistic, right? 93.136.62.103 (talk) 23:06, 29 July 2020 (UTC)[reply]

Sounds perfectly plausible to me, as days with such warnings will often have multiple warnings.--Khajidha (talk) 00:02, 30 July 2020 (UTC)[reply]

Really? That sounds like an extreme amount to me here in Europe. With 8000 probable tornado events in 10 years, how is any part of the city still standing?! How many days a year do such tornado-prone places actually have tornadic thunderstorms? 93.136.62.103 (talk) 00:28, 30 July 2020 (UTC)[reply]

Nowhere near all of those warnings actually result in tornadoes, though. But see tornado alley. --Khajidha (talk) 01:16, 30 July 2020 (UTC)[reply]

Jackson, Mississippi is fairly good-sized, so even if hit by a tornado the damage is likely to be localized within some part of the city. When small towns are hit, it can be a different story. See Xenia, Ohio, for example. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:21, 30 July 2020 (UTC)[reply]

Among the places you can look:

NOAA's Storm Prediction Center - especially in their Severe Weather Events Archive
NOAA Climate Science and Information
the Storm Events Database archive at NOAA's National Centers for Environmental Information ("...Formerly the National Climatic Data Center", the name you will probably recognize if you've been a student of weather science for a while).

Of course, the first place I looked was my paper copy book of the Aviation Weather Advisory Circular, AC 00-06A (or the newer "B" edition, also available at zero cost). In Chapter 11, the chapter on severe weather (thunderstorms), there are annual average charts with isolines around the mean number of thunderstorms per year. Personally, I find this to be the most meaningful way to visualize the data for "where the most storms happen," though you could probably deduce any number of other ways to parse and chart and graph the raw data products.

Quoting directly from that book: "Tornadoes occur most frequently in the Great Plains states east of the Rocky Mountains. Figure 111 shows, however, that they have occurred in every State." Figure 111, a few pages later, normalizes tornado incidence, characterizing the "mean annual number of tornadoes per 10,000 square miles." This is not the only way to compare event-counts - after all, Texas is a lot bigger and more densely-populated than Oklahoma, so while Oklahoma has fewer tornadoes than Texas, Oklahoma also has more tornadoes per person and more tornadoes per square mile! So you can see one example of how things get complicated, when you look into the details - even if you spend just a few minutes digging in! It only gets more complicated as you learn more about climate and statistics and data-science.

If what you specifically seek is the number of issued tornado warnings, you ought to know that an issued warning does not have a one-to-one correspondence with a weather-event. Here is an informational page explaining exactly what it means when there is a tornado alert from the National Weather Service. So if you are trying to interpret the number of events, with any kind of meaningful scientific rigor, you need to be aware of the bias between the rate of occurrence of (one or more) natural event(s) and rate of issuance of one or more alert(s) for the event(s).

The original question asked about a "single location," ... but I won't even try to crack open the proverbial can-of-worms that encases any meaningful effort to define the word "location" in a manner that is suitable for such a task. Shall we compare the weather-events that occur inside a single city? But how can we do so in a fair manner, when we consider Jackson, MS - land area 290 square kilometers - against, for example, Sitka, Alaska - whose city limits include over 12,000 square kilometers? Is it even remotely meaningful to compare "number of tornados per municipality"? And what about tornado events that occur in the great swathes of "unincorporated" areas - events that occur but do not ever encroach on any city at all? Shall we count tornado events per registered place-name for all types of cultural and geographical feature? Each of these, in fairness, do have a specified single "location"... "not a state or county,"... but unfortunately, not all their boundaries are mutually-exclusive...

Among the many ways you could try to resolve these troubles, you could simply allow a researcher to aggregate the data, define a heuristic, and publish their summary results for you... and that is exactly what was described in the summary article linked in our OP's original question. For more details on that particular method, the scientists who did that work have a whole website: Severe Weather at the Iowa Environmental Mesonet, from Iowa State University, with fun polygon datasets for the geometrically-inclined reader.

Nimur (talk) 14:03, 30 July 2020 (UTC)[reply]

July 30

Countries playing their national anthems before space launches

I've noticed that NASA plays the US national anthem before launches (at least during their livestreams). Do other countries that launch spacecraft do the same as well? For example, do Russian livestreams for Soyuz launches play the Russian anthem, does ESA play the French and/or European anthems before Ariane and Vega launches, etc.? Narutolovehinata5 ^tccsdnew 11:36, 30 July 2020 (UTC)[reply]

Blue whale and Argentinosaurus

According to Blue whale, "it is the largest animal known to have ever existed", "reaching a maximum confirmed length of 29.9 meters (98 feet)", but per Argentinosaurus its length estimates range from 30 to 39.7 metres (98 to 130 ft), meaning it was larger by length and not only among "land animals of all time". Should one of the articles or both be corrected? 212.180.235.46 (talk) 12:31, 30 July 2020 (UTC)[reply]

Length and size are two different things. See Largest organisms. --Guy Macon (talk) 12:50, 30 July 2020 (UTC)[reply]

To support what Guy Macon said, Argentinosaurus may have been long, but that doesn't mean it was "bigger," since it could be long but comparatively skinny. Estimates on its mass range from 50 - 100 tons. Blue whales are more like 170 tons. --OuroborosCobra (talk) 14:30, 30 July 2020 (UTC)[reply]

--Guy Macon (talk) 14:59, 30 July 2020 (UTC)[reply]

Why is dew important for plants?

As far as I know it's possible for a plant to leave without dew (we have flowerpot in the kitchen...), then what's the rule that dew play in nature if it isn't necessary? I mean we have rain already and why do we need also dew? --ThePupil (talk) 15:45, 30 July 2020 (UTC)[reply]

Here's one article on the subject.[8] House plants are in a controlled environment, while plants in the wild are at the mercy of nature. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:52, 30 July 2020 (UTC)[reply]

The tone of your question seems odd, like you're arguing to abolish the practice of dew. Our article does a good job of explaining "how" it forms, but as to the "why", see teleological argument. There is no "why". Dew happens, and plants and animals may make use of it or not. 64.235.97.146 (talk) 16:23, 30 July 2020 (UTC)[reply]