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April 17

Crowley's ridge loess

How deep is the loess on Crowley's ridge and what kind of rock is under the loess?Hoover12345! (talk) 00:32, 17 April 2018 (UTC)[reply]

Our article (Crowley's Ridge) does not say, and the only ref that looks promising has a malformed URL. The authors fo that paper are Google Muhs and Bettis. a google on these names show them to be USGS scientists that have published extensively about last-glacial loess formations. -Arch dude (talk) 00:52, 17 April 2018 (UTC)[reply]

I have updated two refs in our article to have working open access URLs for the content. One is an archive, the other is at a different location. Although I didn't check the URL for which I found a new location for the content which is not behind a paywall, I strongly suspect it too was not malformed simply a dead but correctly formatted URL for its time, especially since it is a very similar USGS URL. (I have also added DOIs so the content can hopefully be more easily found, at least behind a paywall, should either URL stop working again.) Nil Einne (talk) 12:49, 17 April 2018 (UTC)[reply]

The map on page 26 of [1] shows a thickness of 5-10 meters. -Arch dude (talk) 00:59, 17 April 2018 (UTC)[reply]
It is underlain by the Lafayette gravel. See [2]. Found by googling for <geology of crowley's ridge>. If you can understand this stuff, please expand our article. -Arch dude (talk) 01:10, 17 April 2018 (UTC)[reply]

How much surface can you plate with one gram of gold

Using modern gold plating, how much surface (of glass or jewels) can you cover per gram of gold? I understand that gold can be spread over a really large surface. I just don't know how large it is. --Doroletho (talk) 13:21, 17 April 2018 (UTC)[reply]

According to this, gold leaf can be as thin as about 0.1 microns. Gold has a density of 19.33 g/cm³. That means that 1 gram of gold has a volume of 1/19.33 = 0.05173 cm³ since 0.1 microns = 1 x 10^-7 meters, that's 1 x 10^-5 cm, so 0.05173/10^-5 = 5173 cm² for the area covered by that leaf. --Jayron 32 13:42, 17 April 2018 (UTC)[reply]

For people as dumb as me: the comma in "5,173cm2" above is a thousands separators, not a decimal point. So that is roughly half a square meter. Tigraan^{Click here to contact me} 13:55, 17 April 2018 (UTC)[reply]

This site says that 1000 leaves of gold leaf will cover 79 square feet and has a mass of 18 to 23 grams. 79 square feet is about 7.3 square meters, so 18 grams per 1000 leaves gives a coverage of 0.4 square meters per gram - very close to User:Jayron32's estimate. Gandalf61 (talk) 15:57, 17 April 2018 (UTC)[reply]

However, when electroplating, much thinner coatings are possible. This site [3] sells microscope slides with 100 Å (i.e., 10 nm or 0.01 micron) coatings, so that would cover ten times the area computed above. Sufficiently thin gold coatings are transparent,. -Arch dude (talk) 16:11, 17 April 2018 (UTC)[reply]

Slightly thicker coatings are transparent red. LongHairedFop (talk) 18:03, 17 April 2018 (UTC)[reply]

I think we ought to distinguish an important practical detail:

The total amount of surface-area covered by one gram of gold is not identical to the surface area you would cover if you added one gram of gold to a real process or machine. There are inefficiencies and losses to consider. Not all the gold ends up where you want it to go!

For every gram of gold input to an electroplating process machine, or to a gold sputtering machine, only a fraction of that gold ends up on the final product. In the case of a sputtering machine, a very huge percentage of the gold ends up as waste-product.

Here's a commonly-cited paper, from the Journal of Vacuum Science and Technology: Ion Sputtering Yield Measurements for Submicrometer Thin Films (1988), which you'll surely find in the archives of any great physical sciences research library.

I'm not very familiar with electroplating - maybe you can get some answers from our regular contributors who are chemists - but I bet electroplating makes more efficient use of the input material than vacuum sputtering! Even still, there are some cases where sputtering is the best and only option - for example, if you want to shoot an scanning electron microscope at a gummy bear, you've got to sputter! The unique preparation of the gold-plated gummy-bear to make it suitable for the SEM is a true art form, a sort of rite-of-passage in the vacuum chamber that one must learn if one wishes to truly master the microscope.

Nimur (talk) 18:26, 17 April 2018 (UTC)[reply]

I know nothing about gold sputtering for electron microscopy, but in other processes using gold, the wast stream is reproicessed to recover the gold. Thus,at the system level, (almost) all of the gold is eventually used. Surely you guys don't jut flush this down the drain? -Arch dude (talk) 22:24, 17 April 2018 (UTC)[reply]

Using the density of 19.3 g/cm^3 and the atomic weight of 197 u, it follows that the surface density of gold is 4.96*10^(-7) g/cm^2, therefore the maximum possible area a gram of gold can cover is about 202 squared meters. Count Iblis (talk) 00:34, 18 April 2018 (UTC)[reply]

Drinking water and hormones

When a human drinks water, does the body release a hormone with diuretic effect? Does it store less water? I imagined that it could exist a similar mechanism to the mechanism of eating/secreting insulin, but related to hydration. Smelling food stimulates release of insulin (which stimulates glucose uptake), since the body anticipates more of it is on its way. --Hofhof (talk) 19:48, 17 April 2018 (UTC)[reply]

You may find some information at one of the items in Water retention. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:03, 17 April 2018 (UTC)[reply]

When humans drink, and that water is absorbed, we produce less of an anti-diuretic hormone called, unsurprisingly, antidiuretic hormone (ADH) and otherwise known as vasopressin. That does imply that under normal conditions we have a constant low rate of release of this hormone which is switched off, or decreased, after drinking. Klbrain (talk) 23:33, 19 April 2018 (UTC)[reply]

Blood volume is controlled by a variety of feedback loops. You may be interested in Atrial natriuretic peptide. -Nunh-huh 03:55, 22 April 2018 (UTC)[reply]

Crowley's ridge

I think my real question is how does something made out of loess and gravel not get eroded away by the Mississippi River over all its meanderings?Hoover12345! (talk) 21:18, 17 April 2018 (UTC)[reply]

How do you know it hasn't already been eroded some? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:36, 17 April 2018 (UTC)[reply]

Because in that part of the river, deposition rather than erosion is the predominant process. 2601:646:8E01:7E0B:792F:2CDD:A29B:FC67 (talk) 03:08, 18 April 2018 (UTC)[reply]

Looking at meander maps going back eons, the Mississippi has been on both sides of the ridge and Crowley's ridge is never under water. — Preceding unsigned comment added by Hoover12345! (talk • contribs) 14:35, 18 April 2018 (UTC)[reply]

April 18

domestic or wild

Are humans considered domestic or wild animals? — Preceding unsigned comment added by 188.159.34.230 (talk) 08:25, 18 April 2018 (UTC)[reply]

Domestic, definitely. We live in homes. Or, maybe not, because no one has breed us selectively (consciously or not) for a specific purpose.

On the other hand, I wonder whether the question makes sense. We define domestic/wild in relationship to humans.--Doroletho (talk) 09:01, 18 April 2018 (UTC)[reply]

Humans possess a number of genetic markers of domestication. Abductive (reasoning) 09:18, 18 April 2018 (UTC)[reply]

Sure, humans undergo neoteny too. --Doroletho (talk) 10:54, 18 April 2018 (UTC)[reply]

This is the "is water wet?" type of question. It's ultimatly an arbitrary semantic distinction that depends on how precisely, and with what definition, you define your terms to start with. The best answer is probably Doroletho's first answer, which is " wonder whether the question makes sense. We define domestic/wild in relationship to humans?" Any attempt to generate a more rigorous answer is likely to generate lots of pointless all-caps writing between two camps who insist they are each right. --Jayron 32 12:48, 18 April 2018 (UTC)[reply]

See feral child. 92.19.169.232 (talk) 15:43, 18 April 2018 (UTC)[reply]

And maybe ponder homeless people. InedibleHulk (talk) 23:57, April 18, 2018 (UTC)

Poul Anderson was very clear on the question, or at least one of his protagonists was. I'm not sure if it was Dominic Flandry or Nicholas van Rijn. Probably Flandry because I don't remember the speech being in broken English. But in any case the answer was "wild", and moreover that that was what they ought to be. --Trovatore (talk) 00:23, 19 April 2018 (UTC)[reply]

Agree that this is a mostly nonsensical distinction for humans, but modern people do meet most of the considerations laid out here. Matt Deres (talk) 14:20, 19 April 2018 (UTC)[reply]

FYI, in addition to this being an obvious invitation to debate, the OP is now blocked. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:48, 19 April 2018 (UTC)[reply]

To clarify, this is no reflection on the OP. The IP has been automatically blocked as a proxy, but then many of the IPs in public libraries are proxies. 92.19.169.232 (talk) 18:03, 19 April 2018 (UTC)[reply]

Sure. A public library in Teheran. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:29, 19 April 2018 (UTC)[reply]

Google finds "about 175" places matching that description. "About 104" for New York City. One for Scranton, apparently more properly known as a building. InedibleHulk (talk) 05:40, April 22, 2018 (UTC)

See self-domestication. 169.228.147.129 (talk) 03:07, 20 April 2018 (UTC)[reply]

How to dissuade conspiracy theorists?

Is there a way to dissuade conspiracy theorists from their conspiracy theories? I've debated conspiracy and fringe theorists before - everything from 9/11 truthers, to anti-vaxxers to climate change deniers. I've been able to occasionally dissuade someone on a particular subpoint, but not the overall theory. Have any psychologists studied this and come up with any effective techniques? Or conspiracy theorists a lost cause? A Quest For Knowledge (talk) 14:12, 18 April 2018 (UTC)[reply]

Reasoning will never make a man correct an ill opinion, which by reasoning he never acquired... Jonathan Swift, 1720. If a person has an unreasonable opinion, by definition, that person does not use facts, reason, and logic to arrive at their own opinions. They will be impervious to any attempt to use facts, logic, and reason to get them to change their opinion. It's a lost cause; our role in society should be to marginalize and minimize the effect of such people on the minds of those who may be influenced by them. If they cared about using reason and facts to arrive at their opinions, they already would have done so. --Jayron 32 14:24, 18 April 2018 (UTC)[reply]

The tendency to search for, interpret, favor, and recall information in a way that confirms preexisting beliefs is called confirmation bias or belief perseverance. It is present to some extent in everyone's thinking. It is probably an adaptive behavior, as taking time to think through every new piece of information from scratch would be dangerous ("What is that stripy thing ? Could it be a tiger ? It certainly looks like a tiger. But maybe it is an illusion. Or maybe I am dreaming ..."). Our article on confirmation bias is very informative. Gandalf61 (talk) 14:31, 18 April 2018 (UTC)[reply]

Not an answer but an observation: despite the fact that, as the previous two editors have righly stated, and is in fact widely known, people do not buy into conspiracy theories based on reasoning (how exactly people "fall into" those beliefs has probably been the object of numerous books, dissertations and articles, maybe it resembles the way people join cults and religions, and maybe even some forms of mental disease) nevertheless it is remarkable that conspiracy theories masquerade as logical constructs, pretend to be rational theories (in constrast to cults and religions). I find this remarkable in view of the fact we know that the primary motivation is not rational. I have my own conjecture as to why this is so, but that would be simply stating an opinion which we're not supposed to do here. Basemetal 16:14, 18 April 2018 (UTC)[reply]

The issue is that conspiracy theories use acceptable logic protocols (like the scientific method or formal logic or other valid decision making protocols) and flip them on their head. These logical constructs are unidirectional. The start with the null hypothesis (tabula rasa, blank slate, etc.) and then use evidence to provide conclusions regarding truth. That is, you start with a question "Does X happen" and then you gather all available evidence without prejudice, assess the evidence using neutral methods of assessments for reliability, and draw conclusions regarding your initial hypothesis. Conspiracy theorists do this BACKWARDS. They start with the conclusion "What I believe is true", THEN they assess evidence based on whether or not it supports the conclusion THEN they develop questions that lead inexoribly only to their conclusions. That's not reason, that's cherry picking and exactly wrong. The thing about conspiracy theories is they all fail the basic test of falsifiability; in the sense that they have assumed that their conclusion could never be proven wrong because it has already been accepted as right, and then they work backwards to gather "proof". Valid reason works the other way, it starts with a proposition which could actually be wrong as much as it could be right, and then willingly accepts that if it is proven wrong, it is wrong. --Jayron 32 16:35, 18 April 2018 (UTC)[reply]

Yes Jayron, everything you say is true, except... you misunderstood my point. Note I said those "theories" masquerade as rational theories. That masquerade is precisely what you so well characterized in your reply. However my question was different, namely, why the need to masquerade? What role does that masquerade play in the process of acquiring believers, since we know those believers do not come to that belief based on rational arguments? Are you saying that those people come to those beliefs because they are deluded by the pretense of rationality of those theories and do not notice their logical flaws? I doubt it. I believe they want to be deluded and choose to ignore those flaws when they are pointed out to them. But then why go to all that trouble. Again, what role does that masquerade play? Two of Karl Popper's favorite examples of non-falsifiable pseudo-scientific theories were Psychoanalysis and Marxism, two theories that insist loudly on how scientific they are. I don't think you can call Marxism or Psychoanalysis conspiracy theories. Here I think we know how people come to buy into them. Those people are in general rational, intelligent, honest people that can be genuinely misled by the pretense of rationality and do not see the logical flaws that you mention until after it's too late. Does that work the same in genuine conspiracy theories such as 9/11, Holocaust as a hoax, flat earth, hollow earth, reptilian space invaders or what have you? My question was simply what role does that rational masquerade play in attracting believers, since we know it is not strictly the logic, flawed or not, that brings them there. I guess every conspiracy theory is different and every conspiracy theorist has their own motivation but it'd be interesting to understand the process, conspiracy theory by conspiracy theory. Basemetal 19:43, 18 April 2018 (UTC)[reply]

I was expanding on your point, not refuting it. I'm sorry that wasn't clear; I thought that by agreeing with you that would have helped make it obvious. Sorry about that. --Jayron 32 23:55, 18 April 2018 (UTC)[reply]

No, I didn't suggest you were refuting what I had said, as you in fact analyzed the pseudo-logical structure of those theories extremely well, just that you left one point out, which is of particular interest to me, namely the question why are they structured that way? how does it help them gain adherents? when we know reasoning and argumentation has nothing to do with it. Of course no one is under any obligation to answer all the questions everbody asks, but I was hoping to hear something about that. Ok, so I'll state my conjecture, which is strictly OR. I'm hoping to hear some sourced data in response if anybody has any: my guess is that their pseudo-logical structure is a kind of weaponization. They are structured like this not so much to convince their adherents, as to give their adherents arguments to answer those who debate them. It doesn't matter that those arguments are flawed, it still gives them something to say in a debate. It may have to do with the fact that we live in a world where the rational, scientific paradigm has gain such preeminence that even they are forced to acknowledge it and disguise their theories as logical constructs (of course we know, as you characterized them, very flawed ones). This is how creationism, that meant simple blind adherence to the words of the Bible, became "intelligent design", supposedly an alternative scientific theory. I assume a conspiracy theory in the 17th century did not need to do that. In fact we would not even call it a conspiracy theory. But in the 20th century they have willy nilly to conform to the main paradigm (even though they in some sense deny it). Anyway, that is strictly OR as I said, I'm hoping to hear some real data from you or anyone who's run into reliable rigorously researched stuff on this question. Basemetal 00:49, 19 April 2018 (UTC)[reply]

We scientists categorically suffer a deficency in formal study of rhetoric; we presume - with neither evidence nor proof! - that the best method of persuasion is a method that relies on correctness. Our equally-intelligent peers who spend just as many years specializing in the social sciences and liberal arts will often trump our case by relying on the defeasible argument - things that we would like to debase as "logical fallacies" or "invalid arguments". Viz., contrast two cases for and against a simple fact: "the earth is ROUND and we have collected of a plethora of observational evidence," opposed against the perhaps more convincing counter-argument, "the earth is flat and I will punch you." The latter argument does not depend on being correct, or reasonable; you cannot win that argument by disagreeing and proving; you cannot win that argument even by accepting the opposing case; as a rhetorical method, it depends on no assumptions; as a means of persuasion, it is faster, more efficient, and more robust than almost any other reasonable method. If we apply academic deconstruction to the argument's rhetorical style, or try to parse whether our opponent's use of the logical conjunction was unintentional, we are punched before we even establish the premises, and long before we follow the premises to their illogical conclusion.

The moral of this story, perhaps, is that we - as scientists - should not immediately assume we will triumph simply because we are correct. If our objective is to be correct, our scientific methodology and its logical underpinnings are our most powerful armament. If our objective is to win, we may often have no recourse except to rely on "incorrect" methods.

Nimur (talk) 16:52, 18 April 2018 (UTC)[reply]

...and when we adopt this wisdom and its methodology, we may defeat our opponent without consequence, because even though though it is incorrect to punch somebody - most places have laws against assault! - the legal system is not held to the same standards of "completeness and correctness" that we demand in, say, a proof of a theorem of abstract algebra. Nimur (talk) 17:07, 18 April 2018 (UTC)[reply]

The simple answer is NO. For example, no amount of evidence will make a flat-earther change his mind about the earth being flat. And the nature of the earth is one of the more easily demonstrable facts. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:52, 18 April 2018 (UTC)[reply]

The OP didn't ask for a method using evidence. They asked 'Is there a way to dissuade conspiracy theorists from their conspiracy theories?'. And there are ways to do that. It is very difficult though - you have to gain their trust and respect and the people they respect are people who are on the same wavelength as them. Dmcq (talk) 20:35, 18 April 2018 (UTC)[reply]

There are all kinds of cognitive biases (here is an extensive list of cognitive biases which are worth studying, avoiding and/or exploiting) and a quick google search on the term "influence" brings up psychologist's Robert Cialdini's book Influence: The Psychology of Persuasion and he also wrote Influence: Science and Practice. Just how deluded, incompetent, intelligent, informed and receptive any audience is, is going to vary a great deal. Moreover, you can't easily influence or "convince" trolls who don't care or likely know that they get it all wrong or probably wrong, because they are getting rewarded in some way (money, attention, humor, esoteric "expertise", etc) regardless of how absurd their dress-it-up make-it-up crack-pottery they espouse is. Then there are the large number of incompetents (that seem to be over-represented in most areas) that don't know or barely know any of the science. Add to that wide-spread preconceptions, misconceptions, and group think, better (saner) explanations might be perceived as flawed, therefore cranks will go to great lengths to gloss over gaping holes in order to maintain their paradigms. Obviously it can be hard to combat that if they are deluded too, but it is possible to be persuasive, and Cialdini has written several books on this topic. -Modocc (talk) 21:25, 18 April 2018 (UTC)[reply]

As fabled BS artist and sketchy limousine explosion survivor Vince McMahon once (allegedly) reasoned "I can't be on TV if I'm dead." That's not to say you should blow up their limos, only that it (in theory) would make them forget everything they think they know about everything forever. Not great for persuasional pursuits, though, which are the better ideas in the long run.

To that end, I suggest simply empowering and assuring them. Sounds like a dumb idea, but my crazy friend here says kooks like conspiracy because they have too little of one and not enough of the other. Perhaps with more confidence, they could find the strength to admit they're wrong about a less important lie they had to cling to before. Or perhaps they could turn into ultraconfident superloons with the potential to trump Trump. Latter's less likely, in my own humble opinion. InedibleHulk (talk) 23:01, April 18, 2018 (UTC)

That link squares with what I've observed over the years: Believers in these goofy theories generally feel powerless. By latching onto one or more conspiracy theories, they feel like they have some sort of "inside" knowledge that the general public is oblivious to, and hence have more power. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:22, 18 April 2018 (UTC)[reply]

Powerless and uncertain. Many powerful people believe things simply for not knowing them as well as they feel they should. But when you know the truth, you don't need to convince anyone about "the truth", especially online. InedibleHulk (talk) 23:44, April 18, 2018 (UTC)

Yes, which is why it's pointless to debate conspiracy theorists except when they try to impose their wacko theories on Wikipedia. The debate over the moon landing stuff still burns in my memory. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:48, 19 April 2018 (UTC)[reply]

Uv dat dey ain’t no doubt. InedibleHulk (talk) 01:21, April 19, 2018 (UTC)

From what I've read, counting racism as one of the most vile conspiracy theories out there, it takes a lot of patient and kind interaction with the hated ethnicity. There may be an "AHA!" moment where it finally clicks that all humanity deserves love, but it's still not an overnight thing.

There's also young earth creationists who advocate a conspiracy theory that evolution is atheist propaganda. Regular, calm, and patient interaction with co-religionists who also happen to accept evolution takes a lot of the bite out of their arguments. They might still occasionally push that we should "teach the controversy" and insist that the world is only 6000 years old, but they throw far fewer hissy-fit tantrums over evolution being the mainstream scientific consensus than YECers who are convinced that evolution is a religious doctrine.

I've also seen that a lot of conspiracy theorists are using the conspiracy theory to displace their worry. Worried about not getting a date? Imagine that some sort of feminazi conspiracy is out to emasculate alpha males, instead of considering reasons why women may not want to date you. Worried about keeping a steady job? Blame immigrants instead of automation shifting the job market from manufacturing to service to... whatever will be left once AI takes off. Helping them make themselves aware of what their real worries are, helping them make themselves aware that their understanding of the "other side" is really a rage totem constructed to enforce a group identity, and helping them learn what similarities they have with the "other side"* to see them as allies (even if they still disagree with them) are all tricky but the surest way to make them give up on these conspiracy theories in these cases. Unfortunately, it's entirely dependent on catching a Teachable moment and knowing how to phrase things so they like what they hear and interpret it as their own realization.

^*

Except Nazis, because the only thing that distinguishes Nazis from any other fascist or nationalist ideology is successful genocide.

Ridicule is a double edged sword. Someone who is open to conspiracy theories might be dissuaded from looking further into that particular conspiracy theory. Devout believers, however, will view it as persecution and triple their volume. Ian.thomson (talk) 23:27, 18 April 2018 (UTC)[reply]

Regarding your comment about the Nazis, they were hardly the only ideology to successfully commit genocide -- Islam has done the same, and so did communism, so you should apply the same yardstick to all of them and by your own standards conclude that there can therefore be no common ground with them either! 2601:646:8E01:7E0B:792F:2CDD:A29B:FC67 (talk) 01:29, 20 April 2018 (UTC)[reply]

Basemetal asks "why". Why? There are probably as many reasons at their are conspiracy theorists, but a few stick out pretty often: 1) Because they are the last believers in an ordered universe, where everything happens according to someone's plan, and since evil things happen, that someone must be evil, and the plan must be very bad; 2) Because there is a certain joy in knowing a secret that no one else does; related, 3) There is a certain joy in being special, in being smarter than all the sheep who can't see what is real; 4) Because however someone arrived at a belief, they have an absolute pathological aversion to ever admitting they might be wrong, building ever more elaborate explanations to avoid the ignominy of having to admit a mistake; and related, 5) some people legitimately suffer from persecutory delusions, in which they believe that anyone who wrongs them for any reason (including such simple things as simply pointing out a mistake they made) must be part of a grand conspiracy against them. That is why they start with the premise, "I am right", and then from there it's just motivated reasoning in an effort to convince themselves that is still the case. Someguy1221 (talk) 01:05, 19 April 2018 (UTC)[reply]

Hence the popularity of this oldie:[4] ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:14, 19 April 2018 (UTC)[reply]

LOL. (Or sigh). Thank you Someguy. I did ask "why". But not "why are there conspiracy theorists, conspiracy theories and people who believe in them?". There's no doubt these are extremely interesting questions but this was not my question. I asked why something else. I tried to be as clear as I could but apparently I failed. Basemetal 02:15, 19 April 2018 (UTC)[reply]

Oh right, well, to get to the "why" that you actually asked, it's very simple: cognitive dissonance. Or more specifically, it's a means to cope with it. Cognitive dissonance itself is merely the act of believing two contradictory things at the same time. The exciting bit is how people do this. You need a way to protect your brain from the pain of contradiction by convincing yourself that the two facts do not contradict one-another. It often surprises people to find out that a lot of conspiracy theorists are actually highly intelligent. Some are even successful businessmen, scientists or engineers. How and why would a person like this believe something so ludicrous as the Sandy Hook conspiracies, for instance? The answer, I think, starts with something from the list I gave above, and then proceeds through cognitive dissonance. Take a smart person who simultaneously believes that A) He is a smart person who makes decisions based on a rational, logical, explicable thought process; and B) alien lizard people comprise a secret jewish islamic atheist deep state that is out to destroy Donald Trump and take away mah guns so that everyone will be gay. The arguments for thought 'B' have to masquerade as scientific, or else the theorist can't believe thought 'A' in his head. He has to render the theory so intricate and convoluted that it simultaneously appears to be scientific but is actually unfalsifiable, so he can pretend it's science without ever having to face being wrong. It has to be complicated enough that he can fool himself. You know, that, or he's actually just insane. It can be hard to tell, and sometimes it seems like one can lead to the other. Someguy1221 (talk) 03:06, 19 April 2018 (UTC)[reply]

Asking detailed questions and letting the believer in the conspiracy theory do most to the talking, may work. This method can also be used more in general where someone believes in something that's inconsistent with the evidence, take e.g. a believer in homeopathy or astrology. Most people are capable of rationally analyzing a problem, they are able to apply rational reasoning to their pet theories and come to the conclusion that it's all nonsense, but for various reasons mentioned in this thread, they choose to not do that. If you then talk to such a person not by lecturing why what they believe in is wrong, but instead ask questions about issues that don't seem to add up and let them just go on explaining that in detail, they can't go on the defensive and invoke the usual conspiracies anymore. So, it's then not about what their opponents are supposedly doing, but it's purely about what they themselves believe in. Count Iblis (talk) 04:29, 19 April 2018 (UTC)[reply]

I can see that falling into accidental indoctrination, though. If you ask a hardcore believer about the things that don't add up, they'll reply that either:

the evidence is wrong or a forgery by the conspirators,
the evidence doesn't really contradict the conspiracy theory in the light of this other part of the conspiracy theory,
the mainstream "account" contains mistakes too and scientists don't know everything, so therefore it's not an issue if the conspiracy theory does not yet explain every facet of reality.

Softcore believers could very well decide "ok, this does seem ridiculous," but this could also become an opportunity for them to start studying the conspiracy theory even more.

Most conspiracy theorists (the ones who didn't need to be on serious medication) I've encountered use conspiracy theories to displace some other fear that they'd feel powerless to change (or else would have to drop some deep-seated personality trait). Without that situation changing, they're less likely to abandon that paranoid mental crutch. Ian.thomson (talk) 05:02, 19 April 2018 (UTC)[reply]

Btw, that is called the Socratic method. Someguy1221 (talk) 04:42, 19 April 2018 (UTC)[reply]

I know people talk about being in an in-group and countering fear. However I wonder if a lot of it isn't an exaggerated form of needing an explanation. One thing a lot of people do is just go for an explanation even if they don't have enough evidence of anything, they just don't seem able to say I don't know yet. Combine that with needing to defend their oown explanations and you're halfway towards a conspiracy theory. Dmcq (talk) 08:42, 19 April 2018 (UTC)[reply]

When reading this abstract one will encounter a misspelling. A missing symbol strongly associated with love and persecution complexes... it's mind-blowing, even insane, or at least entertaining, how events are movers of thought and vice versa. Like NPR's Wait Wait Don't Tell Me's entertaining Bluff the Listener. Some listeners are simply better at distinguishing what is a real scoop or not than others and karma rocks. InedibleHulk's reference states "We are constantly fabricating or “discovering” stories that seem to explain the world." So yes we are doing that, and I cringe when people are unfairly targeted and scapegoated... Damn the grocery store tabloids and the doomsday cults. Sadly.... history.. is replete.... with people that have conspired to jail and kill dissidents, plunder them, nuke, behead and otherwise destroy their enemies, assault each other, mob one another, pillage and subjugate the vanquished (take away their guns as well as enslave them), cheat the suckers, lie incessantly, corrupt the government with insane experiments and tweet propaganda about it. And the gerrymandering and racketeering and the bloody operations and conspiracies, or the mundane comedians are not even wacky stories... sniff. <sigh> The 1977 study with the misspelling I linked to asserts that any truth that involves correlations and/or contingencies can be difficult to process thus our minds take short-cuts, but can get them wrong. Moreover, I very recently read a study that showed that intuitive people are better on average at discovering patterns in images. That's useful if people can filter those patterns appropriately and are thus able to better explore, discover and learn... or become paranoid theorists in their old age if they have impaired executive functions. --Modocc (talk) 14:37, 19 April 2018 (UTC)[reply]

I can't help but notice you mispelled three ellipses in two entirely distinct ways there. Was that some sort of political statement? Or is it a code? InedibleHulk (talk) 22:36, April 19, 2018 (UTC)

In my mind's eye it represents placing and removing the football. So the answer to both your questions is yes. Modocc (talk) 03:25, 20 April 2018 (UTC)[reply]

I think it is a lost cause. In my opinion, a "conspiracy theory" is what we used to call a "paranoid delusion". Bubba73 ^{You talkin' to me?} 17:21, 19 April 2018 (UTC)[reply]

I google imaged the old joke "Just because you're paranoid doesn't mean they're not out to get you." Hundreds of variations of it exist, as prints, T-shirts, whatever. That's the philosophy of the typical conspiracy theorist. ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:46, 19 April 2018 (UTC)[reply]

People are still free to have paranoid delusions without any semblance of conspiracy. Monsters at the foot of the bed, for instance, are usually lone wolves. Figuratively, of course. They're literally more closely related to bats. The point is, they're terrifying for their own sakes and their perceivers', nobody else's business. Same with the idea that these beasts are born when a tree falls in the forest and nobody's around to disprove it; they don't kill your dogs and enter your shack late at night for any convoluted reason that could gain traction online, they're just scared, too. Boring and true, I tell ya! InedibleHulk (talk) 22:51, April 19, 2018 (UTC)

My feeling is that there "conspiracy theories" and disinformation are intimately related. If a lot of people are saying something crazy, there's a fair chance there's a conspiracy behind that. For example, the whole idea of manganese nodule mining started out as a massive CIA conspiracy to lie about a sunken nuclear submarine. [5] Many nasty stories about political figures were distributed during COINTELPRO. In cases like that you can scarcely tell what's going on because the stories were very plausible; by contrast there was the "Roswell UFO crash" where some low-level military guy was apparently given the advice to 'tell them anything' about one of those Mylar weather balloons used to spy on the Soviets. Some of the more popular conspiracy theories don't have fingerprints, but they certainly seem to have political utility to someone. Focusing on "second gunmen" in the JFK assassination is a distraction from the fact that Lee Harvey Oswald had a Communist background and was a defector to the Soviet Union, who plausibly might (or might not) have been ordered by Soviet authorities to carry out the attack. Focusing on explosives inside the World Trade Center might be a distraction from the question of whether an international military-industrial complex might have connived some agreement with bin Laden to encourage him to start decades of war. The "chemtrail" conspiracy idea distracts from the fact that there are chemical tanks on every airplane, i.e. fuel tanks, which emit geoengineering-worthy levels of unregulated sulfur dioxide that authorities don't crack down on (despite causing more than a thousand deaths annually) because it might cool the planet by about six months' worth of global warming. Etcetera. For every valid idea there are crazy interpretations (though never so often as in physics...), and it is even possible that behind every crazy notion is some primordial germ of valid truth. Wnt (talk) 16:21, 21 April 2018 (UTC)[reply]

C4

Any idea why C4 is called C4? Did there where yet in history bombs called C1, C2, C3 which weren't so effective like the 4th Generation or did it where called C4 since the invention of it? --Saegen zeugen des sofas jehovas (talk) 20:29, 18 April 2018 (UTC)[reply]

C4 is short for "Composition C4", part of the Composition C family of explosives (and yes, there was C1, C2 and C3). C4 is the only member of this family still in military service. Composition C was itself preceded by compositions B and A (see RDX). Someguy1221 (talk) 20:49, 18 April 2018 (UTC)[reply]

April 19

PC-rubber

does the "pc" in "pc-rubber" stand for polycarbonate? What is it exactly, a blend or a composite material with two separate layers? SpinningSpark 11:04, 19 April 2018 (UTC)[reply]

No. Polycarbonates (PC) are rigid thermoplastic polymers that may be transparent but are not like rubber. The commonest synthetic rubbers are abbreviated PCP (polychloroprene) rubber such as Neoprene for operating temperatures up to 95°C and EPDM (ethylene propylene diene monomer) for temperatures up to 130°C. DroneB (talk) 12:03, 19 April 2018 (UTC)[reply]

Are you sure of that? I'm seeing some sources that led me to believe it was the plastic that is meant,

"Yee et al. have reviewed the fracture behaviour of a number of two- or three-phase blends including PC-rubber and PC-ABS blends, with some success" in Rubber Toughened Engineering Plastics
"One can also note that the toughening mechanism in ternary blends is similar to toughening in impact resistant polymers. In the PBT–PC rubber blend, the pair PC–rubber in the process of melt blending forms the core–shell particles with rubber being inside." in Encyclopedia of Polymer Blends

Surely PBT, PC, and ABS all occuring in the same context just has to mean plastics? The context I came across this was while researching an article for Warren P. Mason who was trying to find a tougher material for sonar domes. My source says that before Mason these were made of pc-rubber but does not explain what that is. SpinningSpark 14:00, 19 April 2018 (UTC)[reply]

If PC-ABS (ABS is already a copolymer, BTW) is meant as a combination of polycarbonate and ABS, then it's more likely to be an inhomogeneous mixture, not a copolymer. A copolymer would be called PCABS, ABSC or something. This is a fairly common material commercial (Cycoloy is one brand) which is used for injection moulding of pieces like car exterior trim. It's used, rather than ABS, because it has good impact resistance at low temperatures. The microstructure of this stuff is streaky, like wrought iron. I don't know of any true copolymers (maybe a block copolymer?) of PC & ABS.

When you said "sonar dome", my first thought was Neoprene, which is widely used for them. However for the rigid internal structure of a non-magnetic sonar array, then I could see PC-ABS as being useful for it. Andy Dingley (talk) 15:00, 19 April 2018 (UTC)[reply]

That's a US government term for Neoprene, without mentioning any commercial brandnames. There's probably a federal law against Hoovering spilled Coke off the Naugahyde.

Polymer abbreviations are a total PITA (welcome to much of my working day). Every sub-field names its own polymers with the same acronyms. They're all "poly-" something. This one, given that it's a sonar dome, is likely to mean polychloroprene, which is a name, that no-one ever uses, for Neoprene.

It's a chlorinated rubber. Useful stuff, but it means I can't laser cut it. Unless I buy a non-chlorinated functional equivalent, which isn't as good. Unless I buy the Neoprene-branded one, which is UV-stable and weatherproof, and halogen-free: a Neoprene that's called Neoprene but is no longer neoprene. And the differences between "Plastazote" and "Evazote" (they're usually a copolymer, but it varies like crazy) are even worse. FML 8-( Andy Dingley (talk) 14:36, 19 April 2018 (UTC)[reply]

Thanks Andy, but I think you may get on better with a J-cloth than a vacuum cleaner for spilled drinks. SpinningSpark 17:03, 19 April 2018 (UTC)[reply]

1980s CIA flight? Andy Dingley (talk) 21:28, 19 April 2018 (UTC)[reply]

Southwest Airlines Flight 1380

During Southwest Airlines Flight 1380, I understand a woman was partially sucked out the window. Did they have trouble pulling her back in because of the pressure? If so, would breaking another window, thereby decompressing the plane, have made it easier to pull her back in? Would breaking that second window have caused other problems, barring others being sucked out of that one too?

Anna Frodesiak (talk) 11:22, 19 April 2018 (UTC)[reply]

Nah, just open one of the plane's doors

Basemetal 12:38, 19 April 2018 (UTC)[reply]

Once a window has gone (although having someone blocking this will reduce it) the plane depressurises quickly. Even if they could, the crew wouldn't attempt to repressurise it, in case of hull damage.

Nor can you break a window. Those things are extremely strong. They're already holding such a force from the cabin pressure that nothing more you can practically do to them with hand tools is going to annoy them. Andy Dingley (talk) 14:51, 19 April 2018 (UTC)[reply]

This is the latest information that I can find: "While other passengers were able to pull her back into the aircraft, witnesses reported that she was in cardiac arrest as some aboard the plane attempted to revive her". Alansplodge (talk) 17:13, 19 April 2018 (UTC)[reply]

This guy managed to crack the inner window with a punch. SpinningSpark 17:14, 19 April 2018 (UTC)[reply]

That's just the inner window though. There are three layers (two on old aircraft), it's the outer ones which have the real strength. Andy Dingley (talk) 21:27, 19 April 2018 (UTC)[reply]

Has there been any report as to whether the victim was wearing her lap belt at the time? ←Baseball Bugs ^{What's up, Doc?} carrots→ 17:44, 19 April 2018 (UTC)[reply]

The CBS report says one victim, wearing a lap belt (no idea how tight) was injured by blunt force trauma, went out through the window, was retrieved and given CPR, but died as a result of the trauma injuries. No second victim, and I've seen one victim named but not a second. Andy Dingley (talk) 21:42, 19 April 2018 (UTC)[reply]

Hi Andy. Ah, so she wasn't stuck from inside pressure pushing her outward the whole time, right? She was stuck from being in a tight place, forced there from the initial burst of depressurization moving her half way through the window. Once stuck, the plane then completely depressurized because she did not create a perfect seal. Does this sound right? And about the now-moot matter of breaking the other window, windows are strong, yes, that sounds right. A crack from a punch (as mentioned below) is a far cry from getting through the first pane to crack the outside pane enough to depressurize a plane. Anna Frodesiak (talk) 21:24, 19 April 2018 (UTC)[reply]

I have been closely following the official investigation by the NTSB: you can watch the Day 1 press briefing. Most notably, although the claim of a passenger being "sucked out" and "pulled back in" has been reported by the media very frequently, that claim has not yet been repeated by the official accident investigators.

Notably, during the emergency, the pilot of the aircraft did advise air traffic control that one passenger had fallen out of the aircraft. The pilot's radio call in that spirit is now officially on the record - but to evaluate the correctness of that statement, it should be clear that during the emergency, the pilot never independently went back to the passenger cabin to review the situation - she was busy handling the emergency in the cockpit, and was surely repeating "hearsay" from the passenger cabin.

In addition, the pilot also reported an engine fire; at the NTSB press conference, Chairman Sumwalt also indicated that there probably was never any actual fire - but that there are many technical reasons why a pilot might have seen incorrect instrument indications of a fire. Early analysis of the factual data is fraught with complexity, and the technical details are really complicated - which is why the NTSB will spend so much effort to evaluate, and separate, the "factual" from the "probable."

At this time, the only fatality appears to be one passenger, who was not sucked out of any window, but suffered severe, fatal blunt force trauma.

NTSB will continue to update its website with factual information. Chairman Sumwalt has proposed a reasonable timeline of 12 to 15 months for the complete report. It is probable, based on the timelines for other NTSB investigations of aviation accidents, that a preliminary report will be available within a few weeks. "Generally, a preliminary report is available online within a few days of an accident. Factual information is added when available, and when the investigation is completed, the preliminary report is replaced with a final description of the accident and its probable cause."

Nimur (talk) 21:05, 19 April 2018 (UTC)[reply]

The article says that another person died later. Bubba73 ^{You talkin' to me?} 21:18, 19 April 2018 (UTC)[reply]

Surely in the next few days, more statements and assertions will become public, and we can dispassionately evaluate all of the facts. At this time I only know of one fatality.

CBS News has just published an interview with a passenger who claims to have been involved in retrieving the passenger. We will only know whether these statements are completely accurate after a complete review of all the evidence.

Nimur (talk) 21:26, 19 April 2018 (UTC)[reply]

~~Here is a reference to a second passenger dying. Bubba73 ^{You talkin' to me?} 21:31, 19 April 2018 (UTC)~~ [reply]

Whoops, I misread it. Bubba73 ^{You talkin' to me?} 21:33, 19 April 2018 (UTC)[reply]

I believe that woman is the same, one-and-only fatality. Initial media reports, in classical fashion, double-counted a lot of the victims.

This brings up the important and grisly reality of first-responder discipline in a mass casualty emergency. From the textbook: ..."an ideal initial triage area should include... dedicated casualty recorders to identify, tag, register, and record initial triage". This problem is the exact reason why we use these unpleasant paper tags: you glue one to the deceased body, and you tear off the corner so you can hand it to the coroner. One tag, one fatality, no double-counting. This helps make sure that enough emergency responders are allocated to assist those victims who are still alive.

Needless to say, we all hope that our dear readers never need to use this knowledge.

Nimur (talk) 21:38, 19 April 2018 (UTC)[reply]

Speaking of CBS, it's ironic that this happened two days after a 60 Minutes report trashing Allegiant Air's safety record. Allegiant, for all its shoddy maintenance history, has apparently never had a fatality. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:36, 19 April 2018 (UTC)[reply]

Please cite evidence that the 60 Minutes piece was misleading or else don't use words like "trashing". --69.159.62.113 (talk) 22:57, 19 April 2018 (UTC)[reply]

Where did I say it was misleading? Quite the contrary - it scared me enough that if I ever had a chance to fly Allegiant, I would wait for another airline to come along. Just not Southwest. :) ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:39, 19 April 2018 (UTC)[reply]

You said "trash"ing, which means "to subject to criticism or invective; especially: to disparage strongly". It suggests malice or at least a strong expression of opinion, not responsible journalism. If that wasn't your intent, good, but I say it's a POV term be avoided unless that is what you want to imply. --69.159.62.113 (talk) 06:38, 20 April 2018 (UTC)[reply]

You should watch the report and you'll see what I'm talking about. Actually, they probably trashed the FAA as much as they trashed Allegiant. The report might be on the CBS website. ←Baseball Bugs ^{What's up, Doc?} carrots→ 07:11, 20 April 2018 (UTC)[reply]

Watching the report would not produce evidence that it was being misleading. If you mean they were, please cite evidence. If not, please stop using the word "trash". --69.159.62.113 (talk) 03:02, 21 April 2018 (UTC)[reply]

When isn't 60 Minutes misleading or just downright disgraceful in its work? Anna Frodesiak (talk) 23:04, 19 April 2018 (UTC)[reply]

Again, it can't be emphasized enough: anyone who knows all the facts about this accident can't talk to the press. For example, consider this statement from CFM. (Who are those guys? They're the people who make this little contraption). Straight from their press release: "By law, CFM cannot provide information about the accident or details related to it. You may contact the NTSB for updates."

In case you're wondering which law, that would be codified in 49 C.F.R. 830 - 831 and related sections; and usually further contractually specified in the form of a letter of understanding or a signed Party Form; and the information will become public later per 49 C.F.R. 801 and related rules.

What this means in practice is that any news you see in the mass-media is the result of an interview with someone who is categorically not an authoritative, reliable source. Interviews with witnesses are going to yield partial stories and their statements aren't yet vetted for accuracy. People who did know internal details of the investigation, and then published that information in the press, would get in trouble: in fact, in an unrelated accident and ensuing Federal investigation earlier this month, that exact scenario played out after some idiot loudmouth began releasing statements ahead of the official inquiry. If you value truth, fact, and accuracy, you need to exercise patience and let all the independent experts scrutinize the details.

When the preliminary facts are established, the first place you'll see an update is from the NTSB. After that, it's up to the mass media and their army of journalists to sensationalize those facts and sell copy.

Nimur (talk) 02:24, 21 April 2018 (UTC)[reply]

When the airplane window got broken by flying debris, the cabin pressure which is lower than atmospheric and is maintained artificially, dropped precipitously because it got sucked out by the outside air flowing around the aircraft. Such speeding air creates much lower pressure around like air flowing over a convex upper surface of an aircraft wing. The passengers survived because the masks got dropped from the ceiling and they started breathing through them. The masks made a breathing gas mix available to them. How those two males managed to breath through the masks and at the same time to have pulled the woman out of window, I cannot explain. The victim simply got sucked out because of the same force that drove the cabin air outside. It also probably cleared the cabin of everything else which was not firmly attached to the seats. AboutFace 22 (talk) 23:06, 19 April 2018 (UTC)[reply]

A startling number of passengers weren't wearing the masks properly. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:41, 19 April 2018 (UTC)[reply]

If your head gets sucked out of the window of a jetliner at cruising speed, sudden pressure loss is the least of your worries. The aircraft is flying at more than 500 mph, so the air is pushing on your head (roughly) that speed. The details are complex, but to a first approximation the force of the air goes up approximately with the square of speed, so your head will feel approxmately 100 times the force you feel if you stick your head out a car window at 50 mph. I speculate that the victim's neck would break against the window edge or be severely lacerated by any remaining glass. This also explains why two strong men required more than a few seconds to pull the victim back into the plane. Note that an airliner at cruising altitude must operate at high speed to avoid a stall in the thin air, so the pilots could not have reduced speed to lessen the force on the victim even if they had instantly learned of the situation in the cabin and even if they were not contending with a broken airplane.-Arch dude (talk) 00:16, 20 April 2018 (UTC)[reply]

As you say, the details are complicated, but note that the drag equation also includes the density of the fluid as a factor. The plane was at about 32,000 feet altitude, so the air pressure would have been maybe about 30% of what is is near sea level, and that factor of 100 times you mentioned becomes more like 30 times. Still plenty to cause a devastating injury, of course! --69.159.62.113 (talk) 06:48, 20 April 2018 (UTC)[reply]

New Physics? The more you think, the more questions arise. WWII fighter pilots used oxygen masks above 10,000 feet. If they did not, their judgment suffered and they passed out. Here the plane lost hermeticity at 32,000 - a standard cruising elevation and it took the pilot 10 minutes to bring it down to 4,000 feet or so. And in the meantime many things happen that required decision making, physical force and instinct. The victim was pulled out of the window by two gentlemen. Was she hanging out completely just barely holding the broken glass with her fingertips? I doubt the size of the window is large enough to allow an average person through, but this is my guess. In order to perform CPR the victim must have been positioned on the floor of the cabin. Could the mask tethers be that long to reach there? CPR is a demanding physical exertion. The nurse must have held her own mask on her face or someone was holding it for her. Many questions.

I just watched a silent movie "Girl Shy" with Harold Lloyd. One of the scenes is shot in a passenger train car. All benches are occupied except the one in the very front, on the left (as we see it). The benches accommodate two passengers only. On that bench in question sits a young lady, his heart's desire. She is next to the window. Since the train is obviously moving toward the viewer, she is in fact on the right side of the train. Harold performs a few silly attempts to find a seat elsewhere but is chased away by the passengers who occupy those. He has no choice but to sit next to the lady, but he is "girl shy" as we know. He gyrates himself toward her bench and at this moment the train enters a steep curve. The scene of the train on that stretch is shown from outside. It is obvious that the train is making a right turn. Harold loses his balance and he is thrown into that empty seat next to the girl. But she is on the concave side of the moving train, he is moving along the centripetal force which should not have been there. He should have flown in the opposite direction in fact, but of course we forgive the move makers. I think the description of what happened in the airplane that is given to us is equally confusing and unrealistic. AboutFace 22 (talk) 17:41, 20 April 2018 (UTC)[reply]

See TUC --catslash (talk) 19:25, 20 April 2018 (UTC)[reply]

That's for "young military pilots." Even the pilot of that flight was not in that category, although women have a better tolerance for hypoxia. AboutFace 22 (talk) 19:56, 20 April 2018 (UTC)[reply]

In February, we had a long discussion on the topic: loss of cabin pressure... and I linked to a few interesting videos and other resources.

For further reading, start with the PHAK, Chapter 17, Aeromedical Factors, and if you want more, you can read the complete textbook: Introduction to Aviation Physiology.

Nimur (talk) 23:15, 20 April 2018 (UTC)[reply]

The CPR was done (per the reports I've seen) by a firefighter. Who's in similar physical condition to a pilot.

There are walk-around oxygen bottles for the crew. It would be typical for one of those to be given to any passenger who's busy carrying out CPR.

Also there are plenty of cases of CPR being given by someone who themselves is suffering from anoxia. Anoxia is variable, dependent on physical condition and sensitivity to altitude, and often manifests itself mentally first. The CPR respondent could well have had a fuzzy head and felt lousy afterwards, whilst still being able to deliver CPR. Andy Dingley (talk) 14:38, 21 April 2018 (UTC)[reply]

In 1963 TV fiction, William Shatner opened an emergency exit door at an altitude of 20,000 feet while buckled in without suffering a fatal injury.Edison (talk) 03:53, 21 April 2018 (UTC)[reply]

Now we know the truth. Flight's 1380 engine was destroyed by a gremlin :-) AboutFace 22 (talk) 14:00, 21 April 2018 (UTC)[reply]

I'm mostly in agreement with Nimur here particularly on the point about taking care on media reports. Although one thing I'd dispute is I don't think we can rule out the passenger being partly 'sucked out' the window. We just can't say it definitely happened, and even if it did happen being part outside may not relate to her death. The blunt force (or impact) trauma to the head, neck and torso thing appears to be correct, coming from the medical examiner not the NTSB (the NTSB chairperson explicitly said it was not their bailiwick).

The 'sucked out' the window thing doesn't seem to have been confirmed by anyone yet. I earlier read this story [6] (well the NZ Herald version of it [7]) which claims "National Transportation Safety Board chairman Robert Sumwalt said Ms Riordan, who was sitting next to a window, was wearing a seatbelt before she was partially sucked out of the plane." Others say the same thing or similar [8]. This seems to imply Sumwalt actually said she was partially sucked out. It seemed quite relevant to our discussion so I planned to bring it here but in something like this I wanted to take care. So I tried to verify what exactly Sumwalt said, preferably with a recording or transcript or at least with a direct quote.

I still haven't found anything and have fair doubts he actually said that. Some other sources like [9] and [10] say something like "was wearing a seatbelt and sitting next to the window". If they mention the 'sucked out' thing, they don't imply it came from Sumwalt. In fact some sources like [11] are even more circumspect "was wearing her seat belt, Sumwalt said." So did he even say she was sitting next to a window?

I've partially listened to and skimmed through using autogenerated captions both press conferences on Youtube [12] [13] (22 mins 50 seconds is about where he mentions cause of death not being on them) and can't find anything that addresses this. I can't rule out I missed it, auto generated captions aren't perfect. Still I doubt he randomly said the passenger was wearing her seat belt while in the middle of a discussion about engines. So it seems most likely either at the beginning, where he is talking about the window and passenger or in the questions but I didn't find it anywhere. He does mention her during the discussion at about 8 minutes 40 seconds and does imply she was sitting near the window that blew out on row 14 although doesn't actually say she was right next to it instead of one of the other seats, and doesn't mention anything about a seatbelt. He does mention the absence of any acrylic from the window found inside the plane.

Still I'm not saying this is completely wrong, the seatbelt thing seems so widely associated with him that that I suspect it did come from him somewhere. (Suspect but can't be sure, the media have been completely wrong in things like this before.) Either in a later press conference, some part of the press conference that was missed or in some other form. I did come across an interview he did on CNN about this crash (but only in a copyvio), so he is speaking to the media in ways besides those 2 press conferences. (Also the timeline for the ABC News source is interesting, it has the seatbelt thing after the info on the press conference suggesting it came later. Perhaps he said something somewhere after the medical examiner released their report.)

As an example of something else, I also found this where in relation to the reports of the passenger being 'sucked out', Sumwalt is quoted as saying [14] ([15]) "we have not corroborated that ourselves." and "We need to corroborate that". As apparent quotes, I'm even more willing to accept he did say that somewhere, but again I'm not sure where as it doesn't seem to be in either press conference. The lack of a clear timeline on what was said when means that I personally wouldn't completely rule out him having said she was 'sucked out'. Although given what he said earlier, I find it unlikely, since I suspect he would have made a bigger deal over confirming it which doesn't seem to be reflected in any of the sources.

Nil Einne (talk) 06:52, 22 April 2018 (UTC)[reply]

Thank you, Nil Einne. Likewise, at this time I cannot find either confirmation or refutation by NTSB of any details relating to a passenger leaving the cabin.

The website LiveATC hosts and rebroadcasts recordings of air traffic control radio throughout almost all of the USA and a few other regions in the world. These radio recordings are provided by community enthusiasts with hobbyist and home-built radio receivers; they are non-authoritative recordings; but by hobbyist standards and "free-on-the-internet" resources, they are quite thorough.

Using LiveATC archives, many enthusiasts have stitched together the events of Southwest 1380.

Here is one such video, with English transcript: with transcription; and here is another with a map overlay and a hobbyist's reconstruction synchronizing the radio calls with the map - whose data comes from the commercial website FlightAware.com - once again, these are commercial websites that rely on a network of home-built and hobbyist radio receivers, and hobbyist software that aggregates public record data from other sources. They are quite nice presentations; they far surpass a lot of the reporting I saw on major news outlets; but they are not official - they are not even peer reviewed for correctness!

At 8m30s in this reconstructed audio, the captain is talking to Philadelphia Approach explaining her request for emergency vehicles on the ground. "They said there's a hole and someone went out."

Taken out of context, this sounds like a passenger got sucked out of the window.

In context, we have a brief summary of the medical emergency being discussed by two persons who have not actually seen the victim, both of whom are extremely busy doing something else that is significantly more important.

If I may violate my own guidance and speculate wildly: can anybody conceive of a scenario in which a panicked crew member might speak over an intercom: "we have an injury," (long pause); "there is a hole in the airplane," (long pause, during which the victim's resuscitation events have failed, and the victim has been knocked out, in the sense that they have lost consciousness), and then over the intercom: "the victim just went out..."

And perhaps we might see how in that hypothetical scenario, a very busy pilot might summarize the emergency to the ground support team, who is asking how many firetrucks and ambulances are required: "there is a hole in the airplane and someone went out," which is the actual radio call that was made...

And we might imagine that a bunch of hobbyists - nerds who like airplanes so much that they built their own internet radio website to listen to air traffic control radio all day - might have heard that on the radio, thirty minutes before any major news website has broken the story - and those very same nerds might have misconveyed their 100% factually correct representation of the radio call, yielding a completely incorrect reconstruction of an event?

And we might surmise that a sloppy journalist with a tiny budget and a tight deadline might call upon the best experts that advertisement-supported news can buy - and after Googling the event for 11 minutes, that journalist might publish a fact-based verified story so sensational that ad-revenue ticked up for 37 minutes after the story broke. Suddenly, major network news is looking to interview the firemen who performed CPR on the woman who got sucked out of the airplane; meanwhile they can't even correctly tell you how many dead bodies they counted.

Welcome to the real dystopia of fake-news: nobody even meant to make this stuff up!

So: we can understand why this statement might lead to wild speculation. Recognizing how our modern mass-media does not always hold itself to high standards for verification of basic fact, I would believe that a rumor-mill might have rapidly emerged to give credibility to an entire narrative based entirely on one statement from one non-authoritative transcript of an official-sounding thing. In view of the role that non-professional journalists now modulate the mass-media's narrative by enveloping it in "social media", it becomes harder and harder to prove where the story came from, and to demonstrate that every part of a narrative is substantiated by truth.

I do not know if the statement about a passenger who "went out" is correct or incorrect; I do not have all the facts; but I would again emphatically remind our readers by quoting NTSB: "Such releases of incomplete information often lead to speculation and incorrect assumptions about the probable cause of (an accident), which does a disservice to the investigative process and the traveling public."

Nimur (talk) 15:14, 22 April 2018 (UTC)[reply]

One thing which occurred to me I remembered reading something in one of the sources. Initially tried to find it again by general searching but couldn't. Came back here and checked all the sources and fortunately it was in them. The last WaPo source says:

Riordan died of blunt impact trauma to her head, neck and torso, Philadelphia Department of Public Health spokesman James Garrow said Wednesday night.
“The listed cause of death seems consistent with what we’ve heard in media reports,” he said, though he could not confirm the nature of her death. “The cause that we’re listing and have written on the death certificate sounds consistent with what has been reported,” he said, but he could not say whether the injuries were caused by “the fuselage or the air or the window or debris.”

I was initially thinking this was referring solely to blunt impact trauma being the cause of death or maybe that it was ruled accidental. However thinking about it more, I believe I'm wrong, especially since the 'blunt impact/force trauma to head, neck and torso seems a very specific wording which I don't believe was mentioned before the medical examiner's office made these statements. (Actually I was initially thinking when I wrote my first reply that the part came before they later confirmed the cause of death as I didn't read it properly.)

While it's difficult to say for sure without a more complete transcript I think the spokesperson did directly state the cause of death and then followed up with the additional comments which were relating to whether what they saw/found was consistent with media reports on how she died i.e. she was partially sucked out.

I'm not an expert on medical examiners, but I would imagine they could provide an educated guess even without any studies on the specific patterns of injuries whether it's like the injury pattern arose from actually at least partially going through the window or just hitting something in the plane (perhaps the window itself) but no part of the body going through. It seems quite likely going through even just the head for example, would be fairly traumatic in and of itself which significant associated injuries especially when there significant pressure trying to force the whole body through. Of course even from the medical examiner it's still just speculation, even if informed, without further confirmation. Hence the way the comments were worded. (There is also a witness account [16] from a nurse who performed CPR with similar conclusions although one would expect even if I suspect she realise it was likely hopeless that she was more concerned about trying to save the passenger than in examining the injuries and even an emergency department nurse may have some experience but would hardly be an expert in knowing exactly injuries would happen under what circumstances.)

Personally I'm leaning towards the 'sucked out' bit being true to some extent i.e. there was at least some part of her body that exited the plane. It seems clear that she was near the window and that it was broken which would mean significant air pressure pulling things towards the window. And while Nimur has a point on media reports and witness accounts especially in traumatic events for all the witnesses and a plane isn't exactly a good environment to see what's going on for one specific passenger near a window, normally things settle down after a while. In particular, there are generally at least some witness accounts which are closer to the truth. But while there have been questions over various aspects, I haven't seen any over the specific bit of her being 'sucked out', only the extent. (Some seem to suggest she was almost completely out, others seem to suggest a lot less.) The closest is the NTSB saying they haven't corroborated it but I'm fairly sure they'd say that about anything widely reported that they're not yet willing to confirm especially if asked about it.

Nil Einne (talk) 08:04, 24 April 2018 (UTC)[reply]

Plane of sky

What is a plane of sky in scientific context ? Found in the 4th reference in the 54509 YORP article. Googling returns results in computer games, but I didn't find a definition or explanation. -- Juergen 95.223.151.37 (talk) 23:26, 19 April 2018 (UTC)[reply]

That plane would be the one defined by (rather, approximated by) projecting the right ascension and the declination seen by the Earth observer as basis vectors; orthogonal to the "depth" axis or "distance from Earth," which is the orthogonal parameter that is measured by Doppler shift in radioastronomy. Here is a paper on the role of Doppler in NEO observations: The role of ground based RADAR in NEO Observation.... (2006). Here's another paper on using optical astronomy plane-of-sky measurements to constrain the radio or RADAR observations: RADAR Astrometry of small bodies....

I guess the most important thing to realize is that those other plots in our OP's reference - the ones that are NOT in plane-of-sky coordinates - are not "what the asteroid/NEO looks like": rather, those are Doppler plots, and must be interpreted by a RADAR algorithm to estimate a best-fit for the object's true shape. This conceptual hurdle is a very important stumbling block for new initiates learning to watch RADAR.

Wikipedia has an article on one such algorithm: SAMV for pulse/doppler, suitable for the highly-technical enthusiast readers. We also have the much better and more general article on Compressed sensing.

Nimur (talk) 00:04, 20 April 2018 (UTC)[reply]

A- ion in human cells?

Is there something like an A- ion in human cell fluids? Google is not very useful in these cases, since the results that pop up are lithium-ion batteries and blodd type a-. --Doroletho (talk) 23:46, 19 April 2018 (UTC)[reply]

In what context did you see something like this? Someguy1221 (talk) 00:43, 20 April 2018 (UTC)[reply]

I uploaded a screenshot of the book: [17].--Doroletho (talk) 02:40, 20 April 2018 (UTC)[reply]

Ah, thanks. The "A" does not refer to any particular ion, but rather it's a stand in for all large, negative ions. Those would mostly be proteins (the average protein is slightly negatively charged at neutral pH). It's possible they took "A-" from a common nomenclature for discussing acids, where "HA" represents the acid, and "A-" represents the deprotonated acid, and the acid could be anything because it doesn't matter for a particular discussion. Someguy1221 (talk) 04:11, 20 April 2018 (UTC)[reply]

Depending on the context, "A" could stand for "Acid" or "Anion", but really it's just a placeholder symbol. Chemistry has standard sets of "placeholder" symbols used in specific contexts (i.e. R for hydrocarbon, M for metal, X for halogen) see Symbol (chemistry) for some examples. --Jayron 32 10:58, 20 April 2018 (UTC)[reply]

I wouldn't trust the source the source you pulled that text from; looking at the figure, the intracellular ion balance is completely off - far too many anions - that would be very explosive. Klbrain (talk) 21:05, 20 April 2018 (UTC)[reply]

Those are not anions, as per Jayron above. But I think they could have shown it more clearly, to make it distinctive from single elements like Cl or K. Hofhof (talk) 12:55, 22 April 2018 (UTC)[reply]

April 20

Quantum immortals

Assume we discover people who have far outlived the normal human lifespan and/or who survive a series of normally fatal accidents/injuries seemingly against all odds-- like the subject of the quantum immortality thought experiment. Would such a discovery constitute empirical confirmation of the many-worlds interpretation of quantum physics? (This is not a request for debate; I want to know whether I'm misunderstanding the concept of quantum immortality.) 169.228.147.129 (talk) 03:13, 20 April 2018 (UTC)[reply]

No. The chance that you personally observe someone who survives some event that was extremely likely to kill him, is actually unaffected by whether the many-worlds interpretation is true. Consider: If this interpretation is false, and there is only one world, then the chance that someone survives as 1-in-a-zillion event is 1-in-a-zillion. Repeated experiments will tend toward this rate. If the many-worlds interpretation is true, and there are as many worlds as possible quantum states, then the chance that you wind up in a universe where someone has survived a 1-in-a-zillion event is... still 1-in-a-zillion. If the null and alternative hypothesis predict the same outcome for an experiment, then that experiment is incapable of falsifying either. Someguy1221 (talk) 04:01, 20 April 2018 (UTC)[reply]

Thank you, that clarifies things a lot. 169.228.147.129 (talk) 04:04, 20 April 2018 (UTC)[reply]

There's a reason why the various Interpretations of quantum mechanics are called interpretations and not theories: As noted by Someguy1221, they are not testable or falsifiable, and as such, do not occupy the same realm as formal theory. Some physicists even get annoyed by the existence of such interpretations, notably N. David Mermin's exhortation (often misattibuted to others such as Murray Gell-Mann or Richard Feynmann) to "Shut up and calculate!" --Jayron 32 11:03, 20 April 2018 (UTC)[reply]

You can't diagnose quantum immortality in anyone but yourself; however, the concept suffers from some flaws from the perspective of anyone who has ever been knocked unconscious, since why aren't you in the world where you never lost consciousness...? Cf. atman; there is no quantum-based necessity for one single individual to survive to fulfill this many-worlds requirement, even if it is one. This is without even getting into speculations about the quantum nature of consciousness itself.... Wnt (talk) 00:07, 21 April 2018 (UTC)[reply]

(OP here) Wouldn't the same apply to sleep, too? Since going to sleep means a lapse in normal consciousness, under the quantum immortality interpretation we should all be subjectively experiencing constant insomnia. Same goes for anesthesia. 169.228.151.215 (talk) 03:22, 22 April 2018 (UTC)[reply]

The many-worlds interpretation does not imply quantum immortality anyway. So, besides the fact that quantum immortality would only be observable to the person him/herself, it wouldn't necessarily work even if the many-worlds interpretation were correct. In fact, the logic of quantum immortality as invoked in many-worlds can be turned on its head. Suppose I am 100 years old and being of that age is a-typical. I go to sleep and upon waking up, why would I then not find that I'm 25 years old living in some totally different place with no recollection of ever having lived till 100? It seems to me that this is a far more probable outcome given that there are far more 25 year-old copies of me than 100 year old ones. Count Iblis (talk) 03:50, 22 April 2018 (UTC)[reply]

Radiation-loving species

So, what's the deal with https://www.scientificamerican.com/article/radiation-helps-fungi-grow/ ? I haven't been able to find any articles about this fungus not from 2007. Have we discovered more of such radiation-loving species? Or is there some totally mundane explanation not involving radiation? 93.136.60.4 (talk) 03:34, 20 April 2018 (UTC)[reply]

I can't find any papers that reference new species beyond what was in the original paper, though I did find many recent papers about melanized fungi that are merely resistant to ionizing radiation, but that was suspected long before 2007. The phenomenon is still heavily studied, see [18]. But the interest seems to be in understanding the mechanism, rather than isolating new species. Or people have been trying to isolate new species, but they never report the attempts because they never succeed. Someguy1221 (talk) 03:55, 20 April 2018 (UTC)[reply]

That's a little too technical for me. So they're not really thriving in radiation, they'll just survive in a low-medium radiation environment, and high enough radiation will wipe them out just like other known lifeforms? 93.136.96.61 (talk) 18:06, 20 April 2018 (UTC)[reply]

They're thriving in the sense that a little bit of radiation makes them grow faster. But yes, a lot of radiation, and they still die. Though for these little guys, "a lot" is way more than what ordinary organisms could tolerate. Someguy1221 (talk) 19:03, 21 April 2018 (UTC)[reply]

On measuring weight via force

When I stand on my analog bathroom scale and remain still, the scale displays a steady weight. If I move my arms up and down while standing on the scale, the scale displays a variable weight. Reddit explains this is because the bathroom scale is actually measuring force not mass.^[1]

My question is if I found a balance scale big enough to stand on, did so, and had kilogram weights used to balance balance the scale would any arm movement impact the balance?

Similarly, is there an approach for determining the mass of a person that is immune to these perturbations?

Thanks in advance. I find this reference desk a delightful source of information and knowledge. I enjoy all the great information and discussion that takes place here.

128.229.4.2 (talk) 12:47, 20 April 2018 (UTC)[reply]

^ https://www.reddit.com/r/askscience/comments/21hy1o/if_im_standing_flat_on_a_scale_and_swing_my_arms/. {{cite web}}: Missing or empty |title= (help)

I am not aware of any mass determination method that does not involve measuring a force (be it the inert or gravitational mass). Any such method is bound to be fooled by weight-swinging, as adequately explained by the redditors. I do not understand the first question. Tigraan^{Click here to contact me} 13:07, 20 April 2018 (UTC)[reply]

Ok, thanks Tigraan. To clarify the first question, my bathroom scale looks like this, and by balance scale I'm talking about a scale like this. I didnt know if differences between the two scales might change things. 128.229.4.2 (talk) 13:25, 20 April 2018 (UTC)[reply]

Both of these operate by measuring the force of gravity on an object, by countering that force against another force. In the case of the bathroom scale, the opposing force is the force of a spring, governed by Hooke's law; the roughly linear response to compressing a spring allows one to make a simple bathroom scale; double the force, double the compression, turn the dial twice as far. But it's still using force. The second scale, the balance-type scale, takes advantage of torque, in this case if the cross arms are equal length from center to the pan, then equal forces on the pans will exactly balance, because the opposing torques will cancel out. This is still using the force of gravity; just using it twice. Any time you introduce an outside force to the system (such as waving your arms around), you're going to throw it off, since no scale can tell the difference between force of gravity and other forces. They're all just force-measuring devices. --Jayron 32 13:42, 20 April 2018 (UTC)[reply]

Cool! Thanks Jayron32! 128.229.4.2 (talk) 14:09, 20 April 2018 (UTC)[reply]

Not exactly a different principle, but the way to correct for these pertubations is simply measuring the average force over time. If you integrate the force on a scale over 30 seconds, you can swing your arms all you want, but as long as you don't step off the scale, the scale can still calculate your mass very accurately (even a 10 seconds measurement is pretty good). - Lindert (talk) 14:40, 20 April 2018 (UTC)[reply]

As Lindert notes, random arm waving would be a classic example of noise; which can be reduced by common noise reduction techniques; all of which rely on averaging a bunch of measurments over a long period of time; over time the signal to noise ratio generally improves with a greater sampling rate. --Jayron 32 16:05, 20 April 2018 (UTC)[reply]

Yes there is a way to measure mass that will be somewhat immune to arm waving. Suspend a large mass on a string. Measure its position. Now move closer to it. Measure its position again. Wave your arms. No effect. The gravitational force between you and the sphere is not much affected by you waving your arms in the plane tangential to the line joining you and the sphere. There are many other problems of course. Greglocock (talk) 17:47, 20 April 2018 (UTC)[reply]

The waving of your arms is likely to generate sufficient air currents to perturb the position of the sphere several orders of magnitude greater than the movement due to gravitational attraction to you. --Jayron 32 17:55, 20 April 2018 (UTC)[reply]

I like this idea. Indeed there are problems, as Jayron expands, but I liked it nonetheless. I was thinking in this sort of direction as well. Not gravitation, but I was thinking that if mass is equal to density x volume, volume here could be gathered by water displacement. Finding the density of a person might be more complex? Or might just involve a tool(s) I'm not familiar with. 128.229.4.2 (talk) 19:19, 20 April 2018 (UTC)[reply]

Is it known if retargeting ICBMs would take longer if you want an explosion near the maximum possible altitude?

They can reach about 8 kilometres per second so the maximum possible altitude is very high. Sagittarian Milky Way (talk) 16:16, 20 April 2018 (UTC)[reply]

Question does not make sense. One does not want the warhead to go off at max altitude. It diminishes the destructive power at ground level. Re-targeting would take time because ICBM's are pre-targeted (mostly). The ICBM's also have accelerometers etc to ensure that they don't go off prematurely in the event of a bad launch, which could amount to a home goal. The launch teams as far as I know have no way of overriding these safety precautions to allow the warhead to go off at max apogee. If some editor knows better, you can bet that they will correct me in the next post. Aspro (talk) 18:44, 20 April 2018 (UTC)[reply]

Well, it depends on what you're trying to achieve. If you want to kill the most people, then you want a burst at some modest altitude. But if your goal is maximum disruption for fewest deaths, then maybe you're going for a nuclear electromagnetic pulse, which could indeed mean you want to detonate at a high altitude (though as 209 says below, still not "maximum" altitude). --Trovatore (talk) 03:03, 21 April 2018 (UTC)[reply]

Further, there is no "maximum possible altitude" for "ICBM." There are many different types of ICBM missiles. They are designed and fueled to just barely make it into orbit and then follow a ballistic path back to Earth. Smaller ones don't make it to orbit at all. Larger ones not only have the ability to make it into orbit, they are used without warheads to put things into orbit. So, they can obviously reach an escape velocity for an undetermined maximum altitude as it floats off through space. 209.149.113.5 (talk) 18:54, 20 April 2018 (UTC)[reply]

Presumably the interest regards targeting aliens, asteroids, uppity space prison inmates, etc. Then escape velocity is over 11 km/s which means the things as described are tragically unsuited for many purposes. And with so much fuel devoted to climbing it seems inevitable that retargeting must suffer for a lack of reserve. Wnt (talk) 00:04, 21 April 2018 (UTC)[reply]

Back during the days of MAD, all of the possible strategic targets were known in advance and the appropriate parameters were precomputed for each target, so retargeting was a matter of setting these precomputed parameters for the new target. Because the time of flight for an ICBM is quite long, setting a new target in real time makes no sense as the target will have moved. The situation for IRBMs and theater ballistic missiles is a bit different. -Arch dude (talk) 02:51, 21 April 2018 (UTC)[reply]

Neither Peak nickel nor Peak lithium article?

Given the apparent development of the vehicle fleet towards electric vehicles, wouldn't that lead to depletion of possible battery components like lithium or nickel? Or is our back covered for so many decades that's not worth worrying? According to the links in the peak oil article, lots of materials have a peak that can be allegedly calculated. Aren't concepts like 'peak nickel' or 'peak lithium' notable? --Hofhof (talk) 18:30, 20 April 2018 (UTC)[reply]

The general agreement among reliable sources seems to be that "peak lithium" is not a thing. --Jayron 32 18:42, 20 April 2018 (UTC)[reply]

yes, but even if people claim it won't happen, doesn't that make the concept notable, since people are discussing it? --Hofhof (talk) 18:52, 20 April 2018 (UTC)[reply]

Unlike oil or other hydrocarbons, nickel and lithium are elements. The quantity of nickel, lithium, or any other pure element on earth is likely to stay constant, isn't it? ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:06, 20 April 2018 (UTC)[reply]

However the economically recoverable amount may not. See peak phosphorus, for example. Also we are currently burning quickly through our conveniently obtainable helium, which is currently massively underpriced due to the sell-down of the National Helium Reserve. --Trovatore (talk) 20:14, 20 April 2018 (UTC)[reply]

Then, what's all the fuss about Peak copper?Hofhof (talk) 20:27, 20 April 2018 (UTC)[reply]

Lithium#Reserves has some relevant comments, and Nickel#World production could be expanded to do the same for Nickel. Klbrain (talk) 21:54, 20 April 2018 (UTC)[reply]

There's nothing stopping the OP from either creating those articles or creating redirects to portions of other articles. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:56, 20 April 2018 (UTC)[reply]

See [19] and original article [20]. The difference between batteries and fossil fuels is that you consume energy in fossil fuels, but you merely need to use elements in batteries, which means that there are endless ingenious variations possible. Wnt (talk) 00:01, 21 April 2018 (UTC)[reply]

But batteries, even the rechargeable ones, do not live forever and are never completely recycled, so we do actually "consume" the constituent materials, not just "use" them. I think the question, how long can our reserves of nickel and lithium last if we massively build electric cars is not completely meaningless. The same question has been asked formerly relating to neodymium in wind generators, I think 194.174.76.21 (talk) 14:23, 24 April 2018 (UTC) Marco Pagliero Berlin[reply]

Are depressed people more likely to drink alcohol, or does heavy alcohol consumption make people more likely to be depressed?

In other words, does depression make people more likely to drink alcohol? Or does drinking alcohol (a depressant) make a person more depressed? Also, if a depressed person takes a stimulant, like caffeine, can that treat the person's depression? SSS (talk) 22:44, 20 April 2018 (UTC)[reply]

Both. Depression is not a condition. Depression is a wide range of conditions with many different causes. Alcohol doesn't have one effect. Alcohol has many different effects for many different people. — Preceding unsigned comment added by 2600:1004:B158:83F3:4A0:F30A:43F7:3114 (talk) 23:00, 20 April 2018 (UTC)[reply]

Do you have any references? SSS (talk) 23:16, 20 April 2018 (UTC)[reply]

You could start with Depression (mood)#Factors and Alcoholism#Causes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:38, 20 April 2018 (UTC)[reply]

Does personality (in normal people) has to do something with genetics?

How much genetics influence on our personality? Do we expected to be like our father or mother or their relatives based on the genetics? If we look at dogs, then almost everyone knows that there are dog races more calm as well as less calm, and it strengthens my assumption that there is a relation between personality and genetics. But I'm not sure what accepted widely about it in science world and I'd like to know about it. 93.126.116.89 (talk) 22:51, 20 April 2018 (UTC)[reply]

See nature versus nurture. 2600:1004:B158:83F3:4A0:F30A:43F7:3114 (talk) 23:03, 20 April 2018 (UTC)[reply]

There is some evidence that personality may also be affected by the gut microbiome see:[21][22]. Richerman (talk) 23:18, 20 April 2018 (UTC)[reply]

Even identical twins tend to have distinguishable personalities. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:36, 20 April 2018 (UTC)[reply]

Even the inseparable ones tend to not share wives for instance. Non-identical lives, non-identical humans. Sagittarian Milky Way (talk) 02:18, 21 April 2018 (UTC)[reply]

Well, the original Siamese Twins "almost" did. ←Baseball Bugs ^{What's up, Doc?} carrots→ 05:44, 22 April 2018 (UTC)[reply]

It's worth noting that the DNA of identical twins isn't necessarily strictly identical. Different copy number variants have been found, for example, in identical twins. - Nunh-huh 03:44, 22 April 2018 (UTC)[reply]

“Most children resemble the brother of the mother.”

Is there any scientific support to the written in the Babylonian Talmud Baba Batra (110a)? There are two translations to the text that was written originally in Aramic language: 1st translation: “Most children resemble the brother of the mother.” or the 2nd translation: “sons usually inherit the traits of their mother's brothers” (The Encyclopædia of Sexual Behaviour, Volume 2 p.583). Is there any scientific support this claim? 93.126.116.89 (talk) 23:37, 20 April 2018 (UTC)[reply]

Anecdotally, I can tell you that I am a lot like my father in both personality and appearance, and nothing like my mother's brothers. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:40, 20 April 2018 (UTC)[reply]

It's written there "most" so it can be 51% and more, you can be from that minority, that's why I don't look at in a personal examples). 93.126.116.89 (talk) 00:17, 21 April 2018 (UTC)[reply]

"Most" would need to be a lot more than a bare minimum majority. ←Baseball Bugs ^{What's up, Doc?} carrots→ 00:31, 21 April 2018 (UTC)[reply]

Brothers and sisters share 50% of their genes, as do mothers and sons, so the resemblance is 25%. That said, (a) a gene might not affect a woman in the same way, (b) social prejudices may not permit recognition if it does, and (c), most interestingly, there are some sex-linked traits on the X chromosome. So suppose a male grandchild suffers a trait with X-linked recessive inheritance like hemophilia A. Then his mother must be a carrier; in all likelihood she does not have the disease because she has another X chromosome. She in turn inherited that gene either from her mother (who would appear unaffected) or else from her father (who would be affected). As we know she must be a woman, she necessarily inherited one X from each of her parents so the odds of either being a carrier/affected should be the same. If her father was affected, her brother (the child's uncle) cannot have inherited the gene from him; but if her mother was a carrier, then her brother had a 50% chance of being affected depending on which X he received. Well... that means the grandfather and uncle each had 25% overall chance of being hemophiliacs, given that the child has the trait. Which gets us nowhere new. But ... if we suppose the condition is something fatal (and hemophilia may be) then the grandfather was less likely to have had it because then he might have died and not passed the condition on if he had. If it is truly lethal we know it hasn't reared its ugly head in the child's direct line of descent, and only uncles could have had it. It is, therefore, at least conceivable that someone with a particular interest might have penned this verse, but I can't tell you. Oh, and note that Tay-Sachs disease is not on the X, so that's not it. Wnt (talk) 23:56, 20 April 2018 (UTC)[reply]

Thank you for your answer. But I'm not sure that I understood it well. Do you want to say that the statement that I brought from the Talmud isn't correct based on the science nowadays? 93.126.116.89 (talk) 23:03, 22 April 2018 (UTC)[reply]

Well, to recap...

For most genetic traits, a child will resemble its first degree relatives most (50%), and second degree relatives 25%.
For X-linked recessive traits, a male child will not resemble his mother (who is unaffected), but would match his brothers most (50%). If the trait is harmless, he will resemble his mother's father and mother's brother equally (25%).
However, if the trait is quickly fatal, the mother's father did not have it, so the mother's mother is a carrier and the mother's brother had a 50% chance of being affected.

I have not looked at the text from the Talmud in context to understand what situation they have in mind. If it is a general statement about all children and all traits to be read at face value it's pretty much wrong. But if the authors could be assumed to have excluded brothers and fathers "because everyone knows they're more alike", then maybe he was saying that the mother's brother is more similar than the father's brother. And that statement actually is true; the point is, the father's brother shares only a Y chromosome with the boy in question, which has very few genes, while the mother's brother shares 25% to 50% of an X that is quite long and shares many genes that are present as a haploid genome. I haven't looked into whether that is a valid interpretation or not. Wnt (talk) 10:24, 24 April 2018 (UTC)[reply]

Does that actually work out? Both the mother and father will have half a chance of having the same Y gene as a brother, but the father is sure of having the same X gene. Dmcq (talk) 16:16, 24 April 2018 (UTC)[reply]

So is it saying that in the case of children of a mother who has a brother, and lets ignore the case where she has more than one brother, the children will look like a man - and in fact a particular man, the brother? That sounds rather iffy. Perhaps they are saying they will look like the brother bbut not as he hhas grown to as a man? And if they are brother and sister would they not both resemble an uncle? But the sister even so would less resemble the children than her brother? This is getting beyond iffy. Why don't you apply for a grant to check it out from some crowd like the Discovery Institute :-) Dmcq (talk) 10:38, 24 April 2018 (UTC)[reply]

@Dmcq: See the comment directly above. I think there may be a way that this statement makes sense, at least if you interpret it ... talmudically. ;) It is hard to know what assumptions influence the meaning of a sentence from ages past. Wnt (talk) 12:12, 24 April 2018 (UTC)[reply]

April 21

experience day on breast pumps (for milk)

Hello there. I work in a Shop for Sex Toys. I am wondering why there is an "best before..." day printed on the packet of the breast pumps for milk. There is nothing more inside as in a packet of breast pumps for breast enlargement or penis pumps - and the last 2 things have no date on them. The plastic even feels the same of all 3 products, so I doubt that it is because the material may get weak. I can't imagine what may happen if you use breast pumps which are out of date. Any Idea? The day is also printed on pumps which doesn't include the bottle where the milk flows inside. I doubt first that it is because of that bottle, but seems to be not the reason. --Saegen zeugen des sofas jehovas (talk) 03:11, 21 April 2018 (UTC)[reply]

I added the link for you for those who are unsure what a human breast pump is. SSS (talk) 04:57, 21 April 2018 (UTC)[reply]

Googling the subject, one item that came up is this page with several opinions.[23] I've seen expirations on medical equipment before. The points raised about the parts deteriorating and/or accumulating residue sound reasonable. ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:19, 21 April 2018 (UTC)[reply]

However there is consensus [24] that pumps for breast enlargement are ineffective and possibly harmful. DroneB (talk) 19:37, 21 April 2018 (UTC)[reply]

Yes, I was talking about breast pumps for producing milk from an already-lactating woman. The other items are fraudulent. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:52, 21 April 2018 (UTC)[reply]

Calories

This paper says that recovered anorexic patients required more calories to just maintain a healthy weight than people who were never anorexic. It doesn't explain why though. Does anyone know? Is the claim this paper makes even true at all? — Preceding unsigned comment added by 46.149.85.156 (talk) 17:22, 21 April 2018 (UTC)[reply]

Eh? The abstract explicitly compares restricting anorexic patients and bulimic anorexic patients, not restricting anorexic patients and people who were never anorexic (that might imply a normal population). Big difference. SSS (talk) 18:23, 21 April 2018 (UTC)[reply]

This article is published in 1991. So, it's likely outdated. I would say that the information is true, because it is based on observation. But the information may be outdated. Earlier studies are useful in understanding the accumulation of knowledge throughout time, but are not that relevant today. I would suggest limiting your search results to at least 2010. SSS (talk) 19:13, 21 April 2018 (UTC)[reply]

PMC 24200367 is a recentish (2013) review article on the topic. Don't have time right now to look in depth at its findings. DMacks (talk) 23:45, 21 April 2018 (UTC)[reply]

Think that caloriofic intake discussions can be a bit misleading. If someone has very low muscle mass, then what they need to recover is not simply calories per sa . The calories need to come from both carbohydrates and protein in the right ratio. During the end of the second world war, the US forces could not understand why the death-rates of the liberated inmates of concentration camps continued to die, despite being more fed bread than they have every had for some time. Their liberated US POW's from Japan also had a greater mortality more than any of the allied forces. With the benefit of hindsight it is obvious why. The war was costing the US millions of dollars per hour ( not per day). So wanting to be economic they provided the cheapest food. The US doctors that recommend this ( for the purposes of career advancement) should hang their heads in shame for for the number of US personnel that died from their self interested recommendations... Whoops. Nearly missed the point. If an individual is emaciated with low muscle mass, then gets fed loads of carbohydrate, the body needs some protein in the diet in-order to metabolise it. If it is not available in the diet, the body get the protein from the individuals muscle mass. For someone someone who is already emaciated - that results in death. People that have been diagnosed with anorexia need more protein. Aspro (talk) 22:13, 21 April 2018 (UTC)[reply]

I wonder whether it matters to derive protein from solid food or liquid food for emaciated individuals. Solid food still requires chewing, so maybe liquid food like cow's milk or soymilk will be a better alternative? SSS (talk) 23:40, 21 April 2018 (UTC)[reply]

In some cases only parenteral nutrition can save their lives. Count Iblis (talk) 00:05, 22 April 2018 (UTC)[reply]

Let's remember we're talking about recovered, not recovering anorexics. (Although normal weight as used in the abstract seems a better term than recovered IMO, but either way we aren't exactly talking about people who are still emaciated.) Nil Einne (talk) 06:54, 22 April 2018 (UTC)[reply]

April 22

Detecting bird "pregnancy"

Recently I was talking to someone who was feeding gulls, and he pointed out a gull which he claimed was a "pregnant" female, i.e. one that would be laying eggs soon, because it was slightly fatter than the other gulls. (I suggested the neologism "eggnant".) Is it actually possible to tell by looking at a female bird if she's "eggnant," as with pregnant mammals? 169.228.151.215 (talk) 03:27, 22 April 2018 (UTC)[reply]

Sometimes. --jpgordon^{𝄢𝄆 𝄐𝄇} 04:31, 22 April 2018 (UTC)[reply]

Interesting. The gull I mentioned didn't appear to have a bulge on its abdomen, though, it just looked wider across the torso than most. 169.228.151.215 (talk) 04:52, 22 April 2018 (UTC)[reply]

Hens become "eggbound" when they've a bun in the oven too long. They don't look so well but don't look fatter. Gulls are probably similar. InedibleHulk (talk) 06:01, April 22, 2018 (UTC)

Just to note, "probably similar" there is a link to egg binding (unpiped to help readers realize WHAAOE). DMacks (talk) 20:34, 22 April 2018 (UTC)[reply]

They are. InedibleHulk (talk) 06:07, April 22, 2018 (UTC)

The word you're looking for is "gravid". Abductive (reasoning) 06:14, 22 April 2018 (UTC)[reply]

What ever became of the user named something like Kurt Shaped Box who lived for questions like this?73.211.241.4 (talk) 02:31, 23 April 2018 (UTC)[reply]

User:Kurt Shaped Box silently stopped contributing in September 2016. DMacks (talk) 02:54, 23 April 2018 (UTC)[reply]

Shark bite

Can a shark bite through a knight's armor? 2601:646:8E01:7E0B:0:0:0:9A39 (talk) 06:23, 22 April 2018 (UTC)[reply]

That would depend on the shark, and the armor. According to Shark suit, chainmail seems to be preferred, and that was something that knights wore. ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:11, 22 April 2018 (UTC)[reply]

Sharks are known for their numerous teeth and their powerful shearing effect. But what's the simple bite force like, compared to a large feline or hyena? - animals which are known particularly for their crushing ability, rather than sharpness. Andy Dingley (talk) 08:41, 22 April 2018 (UTC)[reply]

"A 2008 computer model estimated that a 21-foot (6.5-meter) great white shark would produce nearly 4,000 psi (17,790 newtons) of bite force, that figure hasn't been directly measured". [25]

Tests by Robert Hardy using a 710 Newton English longbow found that it could penetrate medieval armour at very close range; see English longbow#Armour penetration.

So the answer seems to be "yes", Alansplodge (talk) 12:12, 22 April 2018 (UTC)[reply]

Yes, but this is just a computer model, and this is the peak force at the back of the bite. Add to this that sharks would not apply all their force to all bites.

In reality sharks sharks have saw-like teeth and they shake the prey once bitten to cause a sawing effect. It's about the sharpness more than about the force. --Hofhof (talk) 13:01, 22 April 2018 (UTC)[reply]

Further, I would have to consider the source Alan cites as unreliable, if it can't even get the units right. The PSI is a pressure unit—pounds per square inch, where "pound" means pound force— but the newton is a force unit. 17,790 newtons is 4,000 pounds force, not psi. Or if it meant to talk about pressures, 4,000 psi is 27.6 megapascals, i.e. meganewtons per square meter. --69.159.62.113 (talk) 21:17, 22 April 2018 (UTC)[reply]

The original Journal of Zoology paper seems to be here [26]. It uses Newton except in the abstract. The relevant part seems to be "Assuming isometry, scaling the 35° gape angle data for a 6.4 m, 3324 kg white shark yields maximum anterior and posterior bite forces of 9320 and 18 216 N". While doubts over pop science reports are quite resonable, it's often helpful to at least check out where this claim is likely coming from, particularly if it's peer reviewed. Nil Einne (talk) 07:15, 23 April 2018 (UTC)[reply]

BTW, the PLOS One paper mentioned in the National Geographic source is here [27] and well it's PLOS One so open access. It uses MPa with a psi conversion for the pressures and Newton with a lbs (appears to accurately be pound force) for the forces. The relevant parts seem to be "taxon representative molariform bite forces ranging from 900 to 8,983 N (202 to 2,019 lbs)" and "taxon representative caniniform tooth-pressure values ranged from 195 to 1,344 MPa (28,282 to 194,931 psi)" and "Taxon representative molariform tooth-pressure values ranged from 203 to 1,388 MPa (29,443 to 201,312 psi)". As sort of mentioned in the National Geographic source, the bite forces were measured. (The bite pressures were inferred.) Yes, these are crocodiles, but there's another model mentioned in the Zoology paper "applying a similar FE methodology, computation of the maximal anterior bite force in a 267 kg African lion yields a figure of c. 3300N". I mention these because if Alansplodge suggestion that 710 Newton is enough to penetrate armour, from a pure force standpoint, it doesn't even seem to be even close to being in doubt unless shark (and maybe lion) bite forces are very unusual so the models are way, way, way, way off. I make no comment on other factors. Nil Einne (talk) 07:36, 23 April 2018 (UTC)[reply]

Oh I also came across [28], it seems at least one company does make wetsuits from either stainless steel or titanium mesh [29]. I don't know how these compare to older armour, they're likely designed much more for flexibility and lightness but also likely have a fair amount more tech. According to the first source, the founder doesn't recommend them for great white shark bites although as noted, even without the armour being penetrated there is still risk of significant injury. Another thing mentioned, also in some non RS discussions I came across, is the fact it can doesn't mean it will. Sharks have a tendency to let go if they come across something hard. Nil Einne (talk) 07:55, 23 April 2018 (UTC)[reply]

This video, while not even close to being an RS [30] also mentions the likely ineffectiveness of chainmail wetsuits against a dedicated great white shark. This on cage divers mentions the general reluctance of sharks to bite cages since they don't look like food although I'm not sure how much this applies to a human in armour. (But my understanding is generally humans aren't interesting to sharks, and I wouldn't be surprised if sharks are even less interested in humans in chain mail.) Of course being rare doesn't preclude it happening if you try hard enough, as the few shark attacks and incidents like these [31] [32] show, crap can happen. Nil Einne (talk) 09:09, 23 April 2018 (UTC)[reply]

As some have noted, you don't necessarily have to penetrate armor to harm whatever's inside. Humans are squishy bags of mostly water. If you get hit, the energy still has to go somewhere. Armor simply distributes the force throughout the body, which protects against sharp object penetration but doesn't prevent blunt force injury. This is why blunt weapons like maces were useful, to attack armored combatants by causing blunt trauma. --47.146.63.87 (talk) 09:31, 23 April 2018 (UTC)[reply]

Tsar Bomba's effect on the Earth's Position in space

I was wondering about the effect that a massive explosion like the Tsar Bomba would have on the earth's position in space. I did some back of the envelope calculations as follows: we know that the total yield of Tsar Bomba was 50MT. That's about 210PJ. Most of that energy would have gone into heating the atmosphere, deforming/destroying all sorts of things, creating its crater, etc. But some of the energy would have been a force against the earth's surface. The bomb produced a shock wave which propagated omnidirectionally. Some of it propagated down to the earth's surface (where it in fact, reflected off it). Some of it also propagated upwards. Upon reaching the top of the atmosphere, it would be expected to blow some of the air molecules off into space. It also radiated a large amount of particles upward into space. This mass being displaced away from the earth should have imparted an acceleration on the earth. Even if the mass push upwards was slower than the escape velocity of earth and was simply forced into orbit, the earth would still experience acceleration, and the mass would likely never return to earth as it would be blown off by solar wind. In addition, the large flux of particle and electromagnetic radiation that went downwards towards the earth should have imparted a radiation pressure upon the earth.

I guessed that the yield energy converted into a net kinetic energy change of the earth would be say 10%. I don't really know if 10% is fair or not. I suspect it's possible that almost all of the energy going into motion of the constituent parts of the earth's structure would have been fully dissipated in the deformation of the same, making this an entirely inelastic process. In any case, the 10% figure gives 21PJ. Given that the earth is 5.972e24kg, we therefore have a change in the earth's velocity of 8.39e-5m/s. That's a tiny change, but since 1782259200 seconds have expired since the detonation, we'd expect by now that the earth is around 150km away from where it would otherwise have been. By the year 3061, we'd expect the earth to be shifted by 3000km, and after 1,000,000 years the shift would be 3,000,000km. But when I looked for confirmation of my reasoning I found these links [33] and [34]. They both seem to think that ejection of mass was zero (which I think is a totally incorrect assumption) and therefore conclude that no acceleration was imparted (also incorrect since it ignores the radiation pressure). 103.228.155.110 (talk) 09:52, 22 April 2018 (UTC)[reply]

Your reasoning is incorrect, conservation of momentum needs to be taken into consideration when considering where the energy is directed. The amount of mass ejected into outer space, free from Earth's gravitational pull, is all but negligible, so in fact the vast majority (far greater than 90%) of the blast energy is directed at the air above, rather than the earth. Also, there is a substantial deceleration from the initial detonation velocity by the time any air gets ejected from the atmosphere so the impulse imparted to the earth is basically nothing. Radiation pressure also cannot be thought as acting only on the earth; all forces come in pairs per Newton's third law.--Jasper Deng (talk) 10:59, 22 April 2018 (UTC)[reply]

Imaging the all energy of E=2.1×10¹⁷ went into accelerating some mass

m=2E/v_{2}^{2}

to the escape velocity of

v_{2}=11.2

km/s. Then the kinetic energy of Earth would have changed by

\Delta E=(mv_{2})^{2}/(2M)=2(E/v_{2})^{2}/M

, where M is the mass of Earth. The result is

E\approx 27

J. The change of the Earth's velocity would have been

E\approx 3\times 10^{-12}

m/s – a negligible value. Ruslik_Zero 17:51, 22 April 2018 (UTC)[reply]

It's better to treat the earth as a closed system. The explosion cannot affect the center of mass of the system unless it causes mass to leave the system. Blasting mass into orbit does not do this. The only mass that the explosion pushes out of the system is a mass of any photons that leave the system, and this is inconsequential: it's tiny by comparison to the reflected sunlight. There are several even smaller effects: mass thrown into orbit will increase the system's capture of solar photons and solar wind This is tiny compared to changes caused by the atmosphere expanding due to anthropogenic warming. Yet another tiny effect: if the explosion temporarily affects the earth's albedo, the sun's photon pressure changes as more (or less) photons are reflected back into space. This is is even smaller than the effects on albedo caused by weather, fires, volcanos, agriculture, contrails, etc. -Arch dude (talk) 04:02, 23 April 2018 (UTC)[reply]

Note that large releases of energy, like earthquakes, can alter the Earth's rate of rotation, by moving material around and thereby changing its moment of inertia, but yes, this isn't the same thing as its orbital position. Earth is a big old ball of rock and metal. It takes a lot to move it. --47.146.63.87 (talk) 09:18, 23 April 2018 (UTC)[reply]

Bass cabinet

How do gallien kreuger get such good bass response from rhier small cabinets?86.8.201.80 (talk) 13:31, 22 April 2018 (UTC)[reply]

See Gallien-Krueger for our article. I'm sure that the marketing literature available from their website will address the issue, if not in an entirely unbiased manner. Tevildo (talk) 15:52, 22 April 2018 (UTC)[reply]

I have looked at the website and they do not say how they achieve the low frequency response. That's why I'm asking here.86.8.201.80 (talk) 17:00, 22 April 2018 (UTC)[reply]

Well, for example, on the website we have "[The enclosures] utilize special bracing to eliminate standing waves while providing rock solid structural support to reduce cabinet resonance ... tuned ports, GK’s innovative Horn Bi-Amp System, passive crossover with attenuator for full-range operation ... [the] enclosures are equipped with proprietary neodymium drivers...". Any more detailed information will be proprietary to GK, and not available publicly. See trade secret. Tevildo (talk)

The Wikipedia articles Loudspeaker enclosure and Guitar speaker cover construction techniques that have not changed over many years. DroneB (talk) 10:34, 23 April 2018 (UTC)[reply]

What is the exact reason that woman can't get pregnant while breastfeeding?

What is the exact reason that woman can't get pregnant while breastfeeding? Maybe you can refer me to the relevant article here on Wikipedia and I'll read it.93.126.116.89 (talk) 23:10, 22 April 2018 (UTC)[reply]

Breastfeeding#Mother. Ian.thomson (talk) 23:13, 22 April 2018 (UTC)[reply]

Lactational amenorrhea. Carbon Caryatid (talk) 23:16, 22 April 2018 (UTC)[reply]

The second article (also linked in the first) is an important read. It's definitely not impossible for pregnancy to occur despite breastfeeding. Nil Einne (talk) 09:12, 23 April 2018 (UTC)[reply]

April 23

How does solotone cause to strong smell through sweat glands?

I've read that "fenugreek contains an aromatic compound called solotone, which is responsible for the sweet-smelling "perfume" your sweat emits.". Now my question is how this compound arrive to the sweat glands in the armpit exactly? Is it by the blood or other way? 93.126.116.89 (talk) 04:14, 23 April 2018 (UTC)[reply]

That's sotolon, or sotolone, not solotone, which seems to be a woo-woo multi-vitamin supplement available in Nigeria. Sotolon is a lactone, so it would be absorbed in the small intestine and circulated in the blood. - Nunh-huh 04:49, 23 April 2018 (UTC)[reply]

Yes, the blood, the same way pretty much anything moves around your body. Some lipids do initially get dumped into lacteals instead of the blood, but the lymph returns to the blood eventually, so they still wind up there. Things you ingest only don't wind up in your general circulation if a) they aren't absorbed from your digestive tract at all, and therefore stay there and are excreted; b) if the liver (which is the first stop for blood coming from the digestive tract) stores, modifies, or excretes them back out via the enterohepatic circulation. This is a big deal for any medication taken orally, because the liver can modify it so it's no longer effective, in what's called first-pass metabolism. This is one reason why some drugs can't be or aren't ideally given orally—the other is because most large molecules, like peptides, get digested, which is why things like insulin have to be administered parenterally. --47.146.63.87 (talk) 09:12, 23 April 2018 (UTC)[reply]

It's an interesting question. Eccrine sweat glands work by a merocrine mechanism, which is to say, the vesicles that become sweat are filled inside cells (as opposed to transcytosis). That would appear to imply (assuming no specific transporters) that the lactone is able to cross phospholipid bilayers unaided, which given its structure seems pretty believable. In which case it might more or less suffuse the entire body, intracellular and extracellular, and all secretions from it. Wnt (talk) 12:27, 24 April 2018 (UTC)[reply]

For my grandfather.. planetary motion and ultimate conclusions

My great grandfather (of 91 years and still standing) would like to understand why with all the eccentric orbits of all the moons and planets around us, that we aren't going to be bereft of interplanetary cousins in due course. In other words, with the eccentric nature of everything stellar around us, why aren't we tending to see things move away (or closer) on a cosmic scale? The Rambling Man (talk) 22:10, 23 April 2018 (UTC)[reply]

Eccentricity simply means that the shape of the orbit is sort of like an "oval". Those "ovals" are still stable - they are not tending to eject, or decay, or collide.

In physics, we often find stability in complex systems: this branch of mathematics is frequently considered one of the most elegant and complicated branch of mathematics.

Nimur (talk) 23:42, 23 April 2018 (UTC)[reply]

The long term stability of the solar system is an active area of research, in large part because it is a very difficult problem to solve. Exact solutions regarding the stability of planetary systems have only been achieved for relatively simple theoretical systems, such as one-star two-planet systems. Most everything else gets simulated due to complexity. These simulations have shown that solar systems of many planets could in principle be stable over billions of years[35], but it's not known for certain this is the case with our own solar system from this point forward. Someguy1221 (talk) 03:00, 24 April 2018 (UTC)[reply]

If the Solar System wasn't fairly stable, we probably wouldn't be here to observe it. Moreover, what we see now is the result of over 4 billion years of evolution. The early Solar System was quite chaotic. All the terrestrial planets are probably the results of dozens of planetesimals crashing into each other. It's increasingly thought that the outer planets migrated after their formation, in the process turning the whole Solar System into a shooting gallery. Anything that didn't collide with something else or get swept into a stable orbit was ejected. This may have included an entire extra ice giant (and we may have possibly found it, though this isn't confirmed). Even since then, comets periodically have been perturbed by galactic tides and passing stars, either yanking them away from the Solar System entirely or causing them to fall towards the Sun, which is why they show up here. Also, Triton and Mars's moons are in unstable orbits, and will eventually collide with their primaries, get ripped apart into ring systems, or fly off. It's just that these things take a long time relative to our puny human timescales. --47.146.63.87 (talk) 07:18, 24 April 2018 (UTC)[reply]

The other thing to consider is that the systems are only metastable, meaning that on timescales open for active observation, they aren't varying much. When you expand your perspective from using days or years as your base unit to billions of years as your base unit, the system is highly unstable and stuff has been smashing and careening off in unpredictable directions quite a lot. It's all perspective. --Jayron 32 12:24, 24 April 2018 (UTC)[reply]

The rule of eccentricity is that what goes up must come down ... caveat being, not all orbits intersect the ground. Throw a baseball in the air and its orbit will be highly eccentric; given the chance it would pass within perhaps a few kilometers of the Earth's core at great speed. For a classic Keplerian orbit to happen all the Earth's mass would have to be at its center, and we'd neglect any relativistic frame dragging etc., in which case the ball would return in due course to the pitcher's hand. But, the pesky ground is in the way. Throw the same baseball from a very high tower (that extends far above the atmosphere), with a very good pitcher (like kilometers per second good), and it might pass so far from the Earth's center that it never hits the ground at all. Then it simply goes down, and up again. At the highest point it is moving too slow to avoid falling, and at the low point it is moving too fast to stay in a stable loop around the planet. Wnt (talk) 12:36, 24 April 2018 (UTC)[reply]

Food poisoning

In the most recent news, romaine lettuce is tainted by Escherichia coli in one farm in which the romaine is grown. Somehow, the illnesses are tracked/logged throughout the entire country, and everyone is staying away from romaine lettuce. Some people seem to have a full recovery after a week. Others take several weeks of hospitalization because of kidney failure and diagnosis of HUS. No one has died, though. It just has made the infected people miserable. First of all, I'm curious how the plant is handled at home. I think romaine lettuce is usually eaten raw. Running tap water to wash the heads may not be enough, or maybe the tap water is contaminated. Second of all, what food-borne pathogens are resistant to heat, and how much heat is needed to theoretically kill the pathogen? Third, and this question may be a little off-topic, is eating unwashed fresh produce or raw meats a good way for a person who wants to commit suicide? Or will the pathogens just make the person miserable or make the person lose so much water that he/she dies of dehydration instead? SSS (talk) 23:30, 23 April 2018 (UTC)[reply]

Also interesting to know is whether the use of PPIs plays a role here. Count Iblis (talk) 01:59, 24 April 2018 (UTC)[reply]

The FDA and USDA make manufacturers and growers put lot numbers on their products so that they can be traced. The system is weak for produce, as evidenced by the fact that the source romaine lettuce for this latest outbreak has not been pinpointed. The typical raw produce outbreak starts with either improperly composted manure, or overworked farm workers forced to defecate in the fields by the landowners. No food-borne pathogen is resistant to heat, but some are better able to survive a given temperature. Bacillus cereus spores can survive boiling for as long as it takes to cook rice, if you are looking for a dangerous example. Abductive (reasoning) 05:12, 24 April 2018 (UTC)[reply]

I am reminded of this video. As a cultural note, this behavior of not drinking tap water is not only shared by Chinese people in China, but also overseas Chinese people who recently settled abroad. Foreigners from wealthy countries with safe water pipes and well-treated water come to China to find that they can't drink the tap water. Also, it is not really a cultural practice to eat salads; even the word salad in Chinese is a loanword. Cooking the water and the vegetables may kill the pathogens. SSS (talk) 10:54, 24 April 2018 (UTC)[reply]

Regarding Romaine lettuce, its primary (probably only significant) use is in the U.S. in salads or as a garnish in sandwiches, it is (WP:OBPERSONAL warning) probably the second most common salad green after iceberg lettuce; it's most famous use is in Caesar salad, but it's a common enough green for use in many salads. --Jayron 32 12:17, 24 April 2018 (UTC)[reply]

How the plant is handedld at home: First the housewife normaly removes the tougher outer leaves to expose the more tender, sweeter head. This faily good at removing most of the Escherichia coli that is ubiquduse and existes everywere in dilute quantise too small to cause infection. See: Infectious dose. Problem arises usually with prepared salads. The whole head, Escherichia coli and all go into the washing tanks and the lot gets contaminated, then copped up and put into little convent-to -use-bags of salad – were it continues to multiply. Note: that the authorities are tying to track down the source but not the cause. The cause has been understood for many decades. It is from the use of sewage sludge as a fertilizer which by its nature has very high concentrations of Escherichia coli. When it rains heavily, the drops cause heavily contaminated soil particles to splash up onto the outer leaves. So it is important to wash them... in clean fresh water and not recycled water as used in food processing factories. One may be able to get away with rewashing prepared salad in vinegar/table salt/sugar solution [36] but the extra time and effort involved make traditional home preparation easier, quicker and cheaper than prepared salad. Also, prepared salad bags are fill with a gas so the the cut (wounded) vegetables don't visibly degrade whilst on the supermarket shelf. Once opened the gas leave and by the next day and the rest of the unused bag has to be thrown away as it is going rotten. Were as fresh heads last longer. So, prepared is false economy as well as a potential danger to health. Think about the statics, over ones life time most people get food poisoning at least once so why invite it in? Still, to end on a positive note. One can only die from food poisoning once. Aspro (talk) 15:14, 24 April 2018 (UTC)[reply]

Food poisoning in produce is complicated because of how quickly things like lettuce take up water. Let's say you have a head of lettuce that's perfectly fine. It's picked and dirty water is splashed on it inadvertently. Washing would likely remove enough of that bacterial load to make it safe to eat raw afterwards, though there would always be the risk that enough germs "held on" to make the eater sick. However, if the lettuce is still in the ground and dirty water is splashed on it - say, from the pickers relieving themselves in the fields - the bacteria would get into the soil and thence into the very fibre of the plant. No amount of washing will have an impact there because the germs are inside the cells of the lettuce. In that sense, it's similar to infected chicken - rinsing the chicken would not make it safe to eat raw. Lettuce is particularly susceptible to these kinds of contamination because it's essentially only ever eaten raw; if it was contaminated when you brought it home, there's nothing you can do to render it safer to eat. Regarding safe temperatures to kill germs, see Danger Zone. Matt Deres (talk) 17:03, 24 April 2018 (UTC)[reply]

Matt Deres, if bacteria can get inside the cells of lettuce and other food eated raw, then shouldn't we boil our lettuce and fresh fruit before eating it? Dbfirs 17:12, 24 April 2018 (UTC)[reply]

Ditto. Don't think your right about Escherichia coli existing inside a plant cell. Wrong environment.Aspro (talk) 17:30, 24 April 2018 (UTC)[reply]

This article is an interesting read, and directly relevent to the subject. --Jayron 32 17:17, 24 April 2018 (UTC)[reply]

April 24

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[1]