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June 8

Xylocopa pubescens carpenter bee.

I recorded sounds emitted from a nest of Xylocopa pubescens carpenter bee.

Any information concerning the exact nature of these sounds will be appreciated. Etan J. Tal^(talk) 19:44, 8 June 2019 (UTC)

sounds like squeaking, produces by friction, this friction being caused by the movement of the bee Gem fr (talk) 20:41, 8 June 2019 (UTC)

Mechanics of gas powered rotary cannons

There is a lot of material about the mechanics of electrically powered rotary cannons (e.g. Minigun), but i can't really find any information about gas powered ones (e.g. GSh-6-30). How do they actually, mechanically work? Do they have some sort of gas piston, that cycles the weapon in discrete steps for every single shot, similar to standard machine guns? Do they have a gas turbine, that just sets the barrels in motion like an electric motor does? Something else?

I can only find find sources saying something like "the russian gatlings are gas powered, so they fire faster." But why do they? --178.4.77.247 (talk) 20:45, 8 June 2019 (UTC)

GSh-6-30 gas cylinder

They're gas operated. Gas from the fired barrel is tapped off and works a piston in the cylinder on the side of the frame. This piston has a rack and pinion gear on it, which drives through a short radial shaft to another pinion, which works the radially-toothed ring gear you can see here. That drives the barrel frame around. The piston also cocks the action. A further ring gear and pinion (parallel teeth), also visible here, drives the feed. You can also see the piston return spring here, which is a twisted wire helix. They're prone to failures and the multiple wires keep the action working even if one strand fails.

Compared to the US weapons, the drive is more powerful and so it accelerates to full firing rate more quickly (useful for air combat). However it's too powerful, there's insufficient damping or end stops, and it shakes airframes to bits. The naval mounts are much more robust and survive by sheer Soviet brute force. What it really needs is a gas valve which would reduce the power once up to speed. Andy Dingley (talk) 21:09, 8 June 2019 (UTC)

Thanks a lot! This is much more information than i've found through Google. I would suggest to also put it onto the GSh-6-30 article.

If i may risk some speculation, could my idea of a turbine powered gatling possibly work? It should solve the problem of the piston hammering the mount. Also, like with electric motors, as the barrels spin freely they should be able to eject some misfired catridges without stopping the gun. But i guess it might need a kickstart to get the ROF high enough to sustain operation. --178.4.77.247 (talk) 22:00, 8 June 2019 (UTC)

Turbines are naturally best for low torques at high speeds – which isn't what a firearm needs, at least not for starting. The piston mechanism (which is used in every gas-operated weapon) is a better impedance match (ratio of force or torque and speed) to what's needed here. But it's a bit crude for secondary effects, such as the vibration. No doubt it met someone's Five Year Plan, and that's the Soviet way. Andy Dingley (talk) 23:00, 8 June 2019 (UTC)

June 9

Space-based solar power

Would a Molniya orbit be suitable for a (theoretical) space-based solar power plant? 2601:646:8A00:A0B3:E143:3EF:8DB:B5B7 (talk) 01:37, 9 June 2019 (UTC)

As described in space-based solar power, most proposals have the transmitters in geosynchronous orbit, where they will see the sun ~99% of the time and aiming at the receiver is relatively easy. However, further down in the "non-typical" section, it also describes and links to a proposal for using more exotic orbits, including Molniya, in part because it could be relatively cheaper. Someguy1221 (talk) 02:07, 9 June 2019 (UTC)

Transmitting the power back to Earth seems impractical, as whatever the gain is from placing the solar panels in space (subtracting the losses of transmitting through the atmosphere), that gain can't possibly be worth the extreme cost of placing the solar panels there. That is, you could just use a small fraction of that money to place far more solar panels and energy storage facilities on Earth. Of course, eventually the space costs will come down and we may run out of places to put solar panels on Earth, but by then hopefully we will have fusion reactors working. So, solar panels in space really only make sense for powering devices right there (which does include sending signals back to Earth). SinisterLefty (talk) 03:28, 9 June 2019 (UTC)

At microwave frequencies the atmospheric absorption is considered not that bad. There are all kinds of artist conceptions of cows grazing under the ground antennas, planes flying through the microwave beam without the aircraft or passengers being heated, etc. There is math behind all of it but I have to wonder about public acceptance if the schemes got anywhere near practicality and someone wanted to actually launch them. The lyrics of Home on Lagrange allude to this. 173.228.123.207 (talk) 05:48, 9 June 2019 (UTC)

someone wanted, a century ago. It failed. Wireless_power_transfer#Tesla Gem fr (talk) 11:39, 9 June 2019 (UTC)

Transmitting the power back to Earth IS impractical indeed, and, moreover, the energy cost to send things in orbit is so great it kills the payback. But we also need energy in space. So, maybe, for space application? Gem fr (talk) 11:39, 9 June 2019 (UTC)

Absolutely, solar panels are widely used to power satellites and space ships, at least in the inner solar system. But whether it would ever be practical to send solar power from one collecting station to a remote location, both in space, is questionable. What would be the advantage, instead of just attaching the solar panels directly ? If there are no big advantages, then it just adds complexity, inefficiency in changing energy forms, and potential for accidents, for little benefit. I suppose one advantage would be that the solar collector could be in an orbit that never or rarely passes into the Earth's shadow, but just tripling the size of the solar panels on the station using the power (which does pass into the Earth's shadow), and adding some batteries, might be a more practical fix. However, if the remote station is used, perhaps just using mirrors to aim light at the destination's solar panels when it's in shadow (or even to boost power when it's in light) would be the simplest fix. SinisterLefty (talk) 13:19, 9 June 2019 (UTC)

More (well, OK, less) to the point, following the logic above, why doesn't Earth send the power to space routinely? I'd think that, apart from backing up the most critical systems, a satellite could use that same power transfer tech to get a signal, especially since it would unfurl a very light net of delicate antennae a long way. Wnt (talk) 14:33, 9 June 2019 (UTC)

What would be the advantage ? Any device designed to receive the power source on the satellite would likely weigh as much as the solar panels. And then bad things might happen to planes flying through the power stream, so you'd probably need to put it on top of a mountain to minimize that risk (and atmospheric scattering), with high associated costs. And unless the satellite was in geostationary orbit (rather distant and directly over the equator), it would lose the power stream at least as often as it would lose sunlight. SinisterLefty (talk) 17:30, 9 June 2019 (UTC)

current solar panel don't have impressive power-to-weight ratio: ~100 W/kg. And, funnily, one of the best way to transmit power to space seems to make use of... solar panel (the source is a laser instead of the sunlight); efficiency is greater, and it can be more intense that the petty 1kW/m² of the sun. Now, any risk to lose power is a no-no, and you don't want to rely on heavy batteries or fuel consuming device, so, self-power it (currently) is. Gem fr (talk) 18:43, 9 June 2019 (UTC)

The power-to-weight ratio is infinite, since it's weightless while in orbit. :-) But seriously, the entire lifespan of the solar panels should be considered, so we look at power generated over the entire lifespan (kWh, for example) divided by mass. Batteries, voltage converters, etc., should be included. For the alternatives, like nuclear power, the fuel and all the equipment and shielding would need to be considered. If the satellite or ship mission is only planned for X number of years, then the calculations should only take that amount of time in consideration. SinisterLefty (talk) 00:43, 10 June 2019 (UTC)

Proposals for solar power satellites that I remember involved making the solar panels from lunar material so there was no need to launch it from Earth. Laser propulsion has been proposed as a way to launch spaceships, possibly using light sails. But a high powered microwave beam could be hard to focus on a geostationary satellite. You'd need multiple ground stations, etc. The hope of spaceflight buffs was to just make launching stuff to LEO a lot cheaper, and have high efficiency space tugs to move stuff to GEO. Project Orion (nuclear propulsion) was the most extravagant of the cheap launch schemes. "We could have brought barber chairs" is the quotation I remember. 173.228.123.207 (talk) 23:04, 9 June 2019 (UTC)

Yes, moving production to the Moon would be one necessary step, but to bring the production costs down, the system has to be highly automated, so we don't need the expense of sending people there, and ultimately we need self-replicating robots, so we don't need to keep sending them there, either. All this is decades or perhaps centuries off, though. SinisterLefty (talk) 15:38, 10 June 2019 (UTC)

[un-indent] Folks, let's not get sidetracked here -- I was asking about the advantages and drawbacks of a Molniya (or better yet, Tundra) orbit compared to the traditional proposals for solar power in equatorial orbit (presupposing for the sake of the argument that space-based solar has become feasible, which IRL it hasn't), not about the feasibility of space-based solar power as such! 2601:646:8A00:A0B3:C5E:C820:3A44:3500 (talk) 01:04, 11 June 2019 (UTC)

hum, sorry for the sidetracking. Satellites on those orbit have a changing position and a changing distance to a station on Earth, and, unless I am mistaken, a higher energy cost than on a geostationary orbit. All this rank as drawbacks, while i struggle to see any advantage. If such a power plant were to exist, it most sensible and first use would be to power space objects, and for that, you don't need geosynchonism, but rather synchronism with the objects to be powered, that is, a lower, less costly, orbit. Gem fr (talk) 17:08, 11 June 2019 (UTC)

bird net around wind turbine?

Would it be that difficult/costly to cover wind turbines with nets to prevent them killing birds and bat? Any idea why this is not done?Gem fr (talk) 18:54, 9 June 2019 (UTC)

How fine would the mesh need to be? ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:21, 9 June 2019 (UTC)

Just like nets used as pest control for orchard, I guess. Gem fr (talk) 20:04, 9 June 2019 (UTC)

Googling "bird friendly wind turbine" yields a number of theoretical and practical approaches. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:30, 9 June 2019 (UTC)

indeed, but saw only designs that, for all practical purpose may solve the issue in the future. And I never saw nets mentioned. There must be some reason Gem fr (talk) 20:04, 9 June 2019 (UTC)

What's the business case? Mostly, anything that reduces the efficiency of the turbines would need a good business argument (e.g. reduces bird strikes by X% which in turn reduces maintenance costs by £Y million, at a cost of £Z million in the reduction of electricity generated). If it was good business sense to do so, it would be happening already. The Rambling Man (talk) 20:09, 9 June 2019 (UTC)

It obviously cost something to prevent bird kills. And it seems that it was cheaper (better business) to convince administration to turn a blind eye on those kills. Now, what if the administration required those safety net, so the business had no choice? would that kill it, or just imperceptibly dent profits? Gem fr (talk) 20:36, 9 June 2019 (UTC)

I don't think for a moment that wind turbine operators care about the death of birds, just the ability to maintain turbines creating as much electricity as possible. Putting a net around the turbines (and I'm still unclear as to how that is possible) would inevitably cost money and reduce efficiency. It's obvious that the payback in reduced maintenance is not worth it. Hence they don't do it. The Rambling Man (talk) 20:39, 9 June 2019 (UTC)

I think you have more faith in the intelligence of business people than I do. :-) But I share your curiousity in how such a thing would even work. Would they essentially all get turned into box fans? Matt Deres (talk) 20:58, 9 June 2019 (UTC)

boxed fan, yes, that's the idea. although maybe just covering the most dangerous part (the tip) could be enough (again: if possible and if this doesn't make thinks worse, which could be. I don't know, hence the question) Gem fr (talk) 07:54, 10 June 2019 (UTC)

Maybe it would make sense in the rare case of a bird nearing extinction being threatened by a wind farm. But, in general, the surviving birds will learn to avoid turbines, just as the surviving varmints learn to avoid being hit by cars. SinisterLefty (talk) 00:39, 10 June 2019 (UTC)

This article claims windmills kill far fewer birds than most people think. It cites this article (paywalled), which claims that, per unit of energy generated, fossil-fueled power stations kill something like 15× as many birds. Adrian J. Hunter^{(talk•contribs)} 00:59, 10 June 2019 (UTC)

Unfortunately, from a publicity POV, the windmills are worse. That is, if they can install a camera to monitor a turbine, and capture a bird being sliced in half, and put that on the news, that will garner far more outrage than if 15 birds, miles from the coal-fired plant emitting pollution, die from no apparent cause. Even worse, those plants also kill many people, but it's never obvious who would have lived had the air been a bit cleaner. SinisterLefty (talk) 15:31, 10 June 2019 (UTC)

The fact that no such video ("killer windmill brutally slices cute seagull in half") has been produced yet, despite political incentive to do so, tells you enough about the frequency of such incidents. (Also, as the original article (paywall) says, not all mortality is not due to gruesome slicing: there are also collisions with static parts, electricity lines etc.). Tigraan^{Click here to contact me} 10:36, 11 June 2019 (UTC)

Any bird that manages to kill itself by flying into a stationary object deserves the Darwin award, for improving the gene pool. :-) SinisterLefty (talk) 17:53, 11 June 2019 (UTC)

As others have brought up, lots of man-made things kill more birds, and often more graphically. (Environmental impact of wind power has a table.) Bird strikes are a constant issue for aircraft, and there are plenty of videos of them, but there doesn't appear to be any big movement to ban or heavily restrict aircraft. Many have argued (example) that the concern about windmills and concentrated solar power killing birds is really just NIMBYism. People don't want the things built near them, and then they look around for other justifications to try to sway people, and choose the impact on charismatic megafauna as one. --47.146.63.87 (talk) 00:10, 12 June 2019 (UTC)

There is experience of audio and visual means of scaring birds away from airports. A loudspeaker mimics actual bird distress calls or makes frightening noises. It can broadcast species specific distress cries that scare flocks away. Visual deterrents, such as representations of owls and other natural predators, frighten birds away.See Bird control for airports. Special measures that can be employed include lasers, drones and radio-controlled hawks. DroneB (talk) 15:59, 10 June 2019 (UTC)

June 10

Share a submitted paper with colleagues

Hi; I have submitted a paper to a peer-reviewed journal which is now currently under revision (no decision yet) - a potential employer would like to see the draft now as part of the recruitment process, however, I know of their own strong science department and am now slightly afraid of sending them the draft. What are your take on this - any way to protect my intellectual property prior to the publication? Thank you in advance! --5.151.0.126 (talk) 19:47, 10 June 2019 (UTC)

You have evidence/proof that the paper is your own and the journal's records can corroborate that if you'd ever need to make an intellectual property claim. Sending drafts of papers is common practice when applying for jobs, so I would not be too worried about it. EvergreenFir (talk) 20:36, 10 June 2019 (UTC)

Trap street? Introduce a few small typographic errors in your literature citations, the DNA sequences of your constructs, whatever is relevant to your situation and seems most likely to be used in a plagiarized version. Scan the paper, calculate a checksum and post it to some dated online forum like Github, Usenet, Twitter, whatever. Or do something more professional to archive the version. If the paper gets published with the trapped information, you have them by the short-and-curlies. But my impression is you need contacts involving some kind of "fixer" along the lines of Michael Cohen's dealings if you intend to arrange to blackmail them in a way that is legal and professional, and that I don't know much about. Wnt (talk) 03:12, 11 June 2019 (UTC)

• First of all, check with your co-authors, university etc. that you are allowed to share the draft. (Most likely that is not a problem - information that you are about to publish is no longer confidential - but you do need to check beforehand.) A group email would do.

Look at recently-published articles of the journal you submitted to. If articles have a mention of the date of submission, you have a proof of priority if it comes to plagiarism accusations (you certainly do not want to go there, but si vis pacem para bellum - the mere existence of such documentation will deter unscrupulous parties). (Almost?) all Elsevier and SAGE journals publish such mentions (received, revised, accepted, published dates); I would expect all editors that are not staggeringly incompetent keep that information internally anyway.

There are horror stories about reviewers stalling the peer-review process while whipping their own PhDs/postdocs to reproduce the same results and publish in a concurrent journal (stealing the experimental methods if not the actual data and article), however that is probably not a real issue for you, since (1) it is extremely rare, (2) it relies on the reviewer stalling publication (which they have no reason to do if they are a uninterested third party), (3) you are at the revision stage, so they already lost a couple of months if they wanted to pull that maneuver, and (4) presumably they are not as specialized in your paper's topic than a reviewer would be.

A more significant risk than plagiarism is that they are pulling a scam to get a copy of your paper (free of charge and ahead of publication). I would say it is an acceptable risk to take - assuming a research-related position, a draft paper would unquestionably be useful to evaluate your candidacy, and the information you share is something that would go public anyway. If they start asking about confidential information during the interview (your laboratory's internal procedures, procurement chains, etc.) at the interview, that is a much bigger red flag. Tigraan^{Click here to contact me} 10:28, 11 June 2019 (UTC)

Poor man's copyright doesn't seem to work in the USA. It does in other juridictions Gem fr (talk) 10:32, 11 June 2019 (UTC)

Most journals allow (and sone require) pre-publication of your draft on something like arXiv. That would take care of precedence and allow you to share it with your potential employer. On the other hand (being in a comfortably secure position), I would seriously think if I want to work for an employer whom I distrust in such a basic matter. --Stephan Schulz (talk) 14:43, 11 June 2019 (UTC)

• Preprint server like DSpace or arXiv. Andy Dingley (talk) 19:46, 12 June 2019 (UTC)

June 11

Drunkenness before alcohol

It has long been my impression that I'm rather susceptible to "contact high", especially where alcohol is concerned. When I was a little kid, before I ever had heard of the idea, a couple of glasses of wine to the adults would nonetheless make me rambunctious. One time later on I recall a time when I simply blundered into a group of college students coming out of a sports game and not merely felt drunk from being with them but was literally unsteady on my feet for a bit. Now one possibility is I'm E.T., but more likely is that there's some psychological state of inebriation, which a person can be brought into by social cues, or which can be triggered chemically. According to this model, early man would have developed a tendency to party in a drunken way, perhaps not dissimilar from some of the orgiastic rites recounted the world over where people use things that aren't alcohol and don't seem inebriating to some impartial observers, ranging from invocation loa spirits to kava-kava, to achieve something akin to alcohol inebriation. Alcohol might trigger that accidentally, or perhaps the profuse availability of near-rotten fruit created a situation where it was beneficial for early man to drop everything and hang out on the ground swapping stories and munching, to the point where the propensity to drunkenness literally evolved. Contact high would then result from a strategic requirement for such a state to be widely shared among participants, a sort of social peace treaty where people would somewhat let down their guard to enjoy a common feast.

But is there anything to back up such an idea? Has anyone demonstrated a state of drunkenness without alcohol from some festivity by fMRI, or observed primates acting oddly while enjoying the end of a fruit harvest? It's kind of an annoying thing to search for because of all the more practically oriented alcohol research. Wnt (talk) 09:52, 11 June 2019 (UTC)

If I recall correctly, a state of drunkenness without alcohol from some festivity is often associated with the release of endorphines to the brain (that's why we're a bit looney when enjoying something). Also, alcoholic vapors produced by a drunken person towards some susceptible sober people may play a role - this is the principle a breathalyzer is based upon. Brandmeister^talk 14:12, 11 June 2019 (UTC)

I googled "placebo drunkenness" (a slightly different concept to what you're describing) and found this 2003 report on BBC news, as well as a couple of academic articles. AndrewWTaylor (talk) 14:23, 11 June 2019 (UTC)

Only a hypothesis, but it's possible that it also has to do with nonverbal communication. I failed to find exactly the term I was looking for, but a common aspect is involuntary mimicry (of facial and body expressions, language accent, etc)... —PaleoNeonate – 14:33, 11 June 2019 (UTC)

There's a somewhat disputed theory of mirror neurons that might figure into this. 67.164.113.165 (talk) 10:13, 12 June 2019 (UTC)

gluing together two parts of a broken stone (limestone)

The following question is destined to the those who have the knowledge or the skills: what's the right way to glue two parts of a stone, that has broken up into two pieces as a result of a hit ? what material/s are recommended for that purpose ? Thanks, בנצי (talk) 10:08, 11 June 2019 (UTC) השאלה מיועדת לבעלי ידע או ניסיון: איך מדביקים שני חלקי אבן (גירנית), ובאיזה חומר/ים יש להשתמש ? שני החלקים הם יחידה אחת, שנחלקה לשניים עקב מכה. תודה, בנצי (talk) 10:08, 11 June 2019 (UTC)

• Please, WP:SPEAKENGLISH. Bazza (talk) 10:18, 11 June 2019 (UTC)

  Please, use translate.google.com or something. It's just the same thing in (presumably) Hebrew. Wnt (talk) 15:37, 11 June 2019 (UTC)

  @Wnt: I'm not sure who that comment is aimed at. WP:SPEAKENGLISH doesn't mention translate.google.com, or any other translators. The OP could have translated their second text to English (for the English Wikipedia) using such a translator first. Common courtesy, rather than expecting people you want to help you to do it for you. Google says the extra text is "The question is for those with knowledge or experience: how to glue two pieces of stone (chalk), and what material (s) should be used? The two parts are one unit, divided by two due to a blow. Thanks, Bentzi". Bazza (talk) 16:03, 11 June 2019 (UTC)

As Wnt said, Hebrew and English parts of the question are identical in meaning. For repair, I'd use a landscaping adhesive. Pick a color that matches the stone in case some adhesive squeezes out. Try to match the two parts exactly as they were before the break, and use as little adhesive as possible so it doesn't squeeze out. Dr Dima (talk) 19:44, 11 June 2019 (UTC)

• Impossible to say precisely without knowing more details. In particular, how neat the result needs to be - the answer is different for a garden wall vs. a museum conservation repair.

Mostly such a repair would involve insetting a non-corroding metal dowel. This is glued into place (traditionally) with lead-based alloys (or Cerrosafe, for good work), or even molten sulphur! Modern work would use an acrylic adhesive (these are sold commercially for putting screws into stonework). You could also use an epoxy adhesive, which is what most people would think of first. Use a good epoxy though, like West System.

Really though someone, who is skilled at such repairs, needs to look at the piece. Andy Dingley (talk) 11:04, 11 June 2019 (UTC)

A very quick search turns up [1] as a top hit. Is that a stab in the right direction or do you have a different application? Wnt (talk) 15:37, 11 June 2019 (UTC)

Another important factor is what conditions it will be subjected to following the repair. If it will sit on a shelf in an air conditioned room, that's relatively easy. If it will be outside and subject to all ranges of weather, that's quite a bit trickier. SinisterLefty (talk) 20:16, 11 June 2019 (UTC)

Dosimetric values for sensing ionizing radiation

I have read in a blog that immediate physiological clues of ionizing radiation - smell of ozone (apparently due to ionization of air), metallic taste and eye irritation - begin at or above 10 roentgens. Are there reliable sources for this, mentioning minimal dosimetric threshold for such feelings? Thanks. 212.180.235.46 (talk) 13:55, 11 June 2019 (UTC)

Although many effects are possible, the most common immediate signs and symptoms of radiation poisoning are nausea and vomiting.

Here is Understanding Radiation, a guide for emergency first responders from Lawrence Livermore National Laboratory.

Here is Radiation Sickness from the Mayo Clinic. Again, the early signs are nausea and vomiting.

Nimur (talk) 14:54, 11 June 2019 (UTC)

I know. I'm more interested in corresponding dosimetric values, e.g. to what value do ozone smell and metallic taste correspond to? I only know that this means strong radiation. 212.180.235.46 (talk) 15:10, 11 June 2019 (UTC)

I'm not certain that there's any meaningful threshold: ozone can be produced by chemical reactions that have nothing to do with incoming radiation; and ozone can also be produced by low doses of ultraviolet radiation (which, to be fair, may qualify as "ionizing" radiation - but not always); meanwhile, arbitrarily-high incidence of certain wavelengths of ionizing radiation might produce negligible ozone. Here's a detailed, scientifically-accurate FAQ from NOAA: How is ozone formed in the atmosphere?

As far as the symptom of "metallic taste," that's also one whose correspondence to ionizing radiation is weak, at best. For example, Burning Mouth Syndrome (from Mayo Clinic) lists "metallic taste" as a common symptom. I recall reading about this symptom, because not too long ago, that exact article came up in a discussion on Wikipedia's Science Reference desk - ... about peach allergies.

After reviewing a bunch of reputable sources that I trust - things like the radiology health guides at our national labs - and finding zero discussion of user-reports of "ozone smell" and "metallic taste" associated with radiological health, I would personally conclude that these are not common symptoms. If you found a blog or other discussion, they may be repeating apocrypha that is unfounded in scientific experiment.

If a subject smells ozone, it is probable to conclude that they are being exposed to ozone, not to radiation. Any direct connection between radiation exposure and ozone is tenuous and scenario-dependent.

If a subject reports a metallic taste, that may be a sign of a different underlying condition - possibly connected in some fashion to an acute or chronic radiological exposure, and possibly not.

I don't think I can find any reason to associate those two symptoms with particular dose thresholds; and I can't find any reliable resource that makes that connection either. At low doses, a subject might not notice exposure (even if harm is being caused); at higher doses, a subject will typically experience nausea; and even if we raise the acute exposure to exceptionally dangerous levels, a subject will begin experiencing the more grisly symptoms, like rapid hair loss, diarrhea, blood-loss, and exhaustion or unconsciousness; but I cannot find reports of "tastes" and "smells."

If anything comes to my mind, it sounds like somebody's mixing up symptoms - after all, a lot of emergency and military training doctrine lumps together all the chemical and radiological safety into one set of doctrine - because whether the cause is radiological or chemical, many of the "next steps" for containment, evacuation, and treatment are exactly the same. Bad smells and bad tastes can also be an indication of exposure to lots of chemical hazards, but I do not think they are commonly associated with nuclear (or ionizing) radiation exposure.

Nimur (talk) 20:26, 11 June 2019 (UTC)

Can you link us to the blog post you referred to? Ionizing radiation can, by definition, ionize the oxygen in air, which can generate ozone; it can also produce a lovely blue glow. But as Nimur notes, this is not a guaranteed way to measure radiation, as the amount of ozone produced will depend on environment. Air is an uncontrolled mixture of chemicals which can produce a lot of different chemical reactions when energized. Also, as the article notes, the roentgen is an old unit that is generally avoided today. The roentgen itself measures air ionization, which does not have a simple relationship with things such as the amount of radiation absorbed by tissue, which is what matters for symptoms of radiation sickness. Obligatory meme: "Only 3.6 roentgen. Not great; not terrible, like a chest X-ray." --47.146.63.87 (talk) 23:46, 11 June 2019 (UTC)

June 12

Chernobyl

Hi. After watching the mini-series and reading alot of articles on WP about the disaster, I read about Valery Khodemchuk. The list states "likely killed immediately; body never found, likely buried under the wreckage of the steam separator drums". Would there be any remains left of him, or would it all be destroyed due to the radiation? Thanks. Lugnuts ^{Fire Walk with Me} 10:26, 12 June 2019 (UTC)

It's difficult to find factual information on the condition of one specific individual. Contemporaneous news stories reported in Western newspapers, like this 1986 story from the Los Angeles Times, are sparse on detail, except to say that the unrecovered remains will be left inside the building inside the protective concrete casing. The condition of the remains is unknown; it may have been exposed to ionizing radiation, fire, water, and debris.

From my archive of emergency preparedness, here are some helpful links:

• Explosions and Blast Injuries - A Primer for Clinicians, from the CDC Mass Trauma Preparedness website
• Bombings: Injury Patterns and Care from the American College of Emergency Physicians - a full course including two segments on radiological effects, and the handy pocket reference to injury patterns

These resources help medical responders know what to expect, and help first responders prepare for the logistical and psychosocial effects of a major nuclear incident.

From a more academic approach, here is a 1954 publication, Pathology of Total Body Irradiation in the Monkey. This is research from an era when government researchers private-sector individuals in Western societies conducted experiments to see what would happen if...

If you really want to know what happens to a body after it dies, you might start by reading about the methods of forensic pathology, so that you learn what normally happens; and then read onward to see what is unique to a highly-irradiated individual.

Even in a conventional disaster, human remains are not always locatable. For example, the fire near my home in 2018 killed more people than the Chernobyl nuclear incident, and there are still more persons reportedly killed whose remains were never located. They may be in unknown locations; they may be so severely damaged by trauma, fire, debris, or crushing, that they are unidentifiable.

Nimur (talk) 12:26, 12 June 2019 (UTC)

Thank you. Lugnuts ^{Fire Walk with Me} 15:09, 12 June 2019 (UTC)

Radiation could potentially preserve a body, by killing off all the bacteria that would normally decompose it (however, bacteria are resilient, so it would take a lot of radiation). That would leave dehydration/mummification as a possibility, but if enough moisture was sealed inside, that might not have happened, either. SinisterLefty (talk) 17:25, 12 June 2019 (UTC)

Ionizing radiation doesn't do much to the macroscopic structure of organic tissue. It's bad for living things because it damages or kills cells, but it won't turn a dead body into a puddle of goo (unless it manages to heat it to a quite high temperature, but for that you would need a substantial amount of radiation focused directly on the body, like what you'd get from chucking it into the path of a particle accelerator beam). Indeed, as others have noted, irradiation is actually a good way to preserve organic material, because it damages or kills the microbes that otherwise decompose it, and that's why it's used as a method of food preservation. When an unpreserved corpse decays, some of that is due to liberation of enzymes from tissues and organs, but most of it is microbes, and other decomposers such as insects and fungi, beginning to digest it. --47.146.63.87 (talk) 19:13, 12 June 2019 (UTC)

How many microohms of resistance do the circulating US coins have?

If you cleaned them to the bare, uncorroded metal and soldered square contacts the thickness of the coin to the rim, 180 degrees apart. The 1981 to 1909 penny must be pretty damn low as it's almost pure copper and not that big (19mm), is it thick and small enough to outconduct all the undebased silver coins? Sagittarian Milky Way (talk) 13:07, 12 June 2019 (UTC)

Electrical_resistivity_and_conductivity quotes the resistivity of Copper 16.78 nΩ·m (at 20 °C). It is difficult to make an accurate resistance measurement of a coin material by the means described and it is more appropriate to measure its Sheet resistance using Four-terminal sensing. Typically a constant current is applied to two probes, and the potential on the other two probes is measured with a high-impedance voltmeter. For details see Van der Pauw method. The composition of US penny coins from 1909 is copper 95%, tin/zinc 5%. Due to wartime shortages of copper the 1943 steel cent was struck in zinc plated steel that tends to rust around the edge, being the only regular-issue US coin that contains no copper and can be picked up with a magnet. DroneB (talk) 13:36, 12 June 2019 (UTC)

The Big Bang & Evolution

User was indef'd. ←Baseball Bugs What's up, Doc? carrots→ 21:54, 12 June 2019 (UTC)
The following discussion has been closed. Please do not modify it.
Has The Big Bang & Evolution been proven, If so, Why are they still addressed as theories? What I mean is that for a long period of time in history there has been debates about the origin of life & some people have held it that a supreme being or beings were responsible & some have held it that the universe naturally came into being through natural selection. There have been many scientific contradictions but there seems to be a favouring of natural selection. I can cite science articles, books & passages that speak for/against both sides to prove that I am not giving my own personal opinions & biases but looking & presenting the implications objectively. This is a discussion that should be had because if anything in life is sacred, the truth is...A true scientists should look at the implications objectively,be prepared to be proven wrong & be willing to accept it. Again I will stress that I am not giving any of my own personal opinions or biases but instead, offering to present evidence while also willing to accept the possibility of being proven wrong. I have no intention of deceiving, misleading or manipulating anyone which is why I will only present & address without being personally involved. I only ask that my debate opponents (no disrespect) who may be skeptics do the same because you have every right to expect the same from me. — Preceding unsigned comment added by Repent.The End is Near (talk • contribs) 14:21, 12 June 2019 (UTC) "Proof" has many different, but related meanings. In the strict mathematical/logical sense, nothing about the real world can ever been proven - it's always possible that you are kept imprisoned by an evil demon that just feeds your brain inputs that simulate a particular sense of reality. In that sense, science never "proves" anything. A scientific theory is a coherent body of knowledge describing aspects of reality, and allowing us to make predictions. If such a theory agrees with observations and if more and more of its predictions come true, we eventually consider it "provisionally true". This provisional truth of science is a much stronger level of truth than e.g. that accepted by most legal systems even in criminal cases. In this sense, evolution is both an observed fact and a proven theory (i.e. we can observe actual live evolution as well as past instances of evolution, and the theory of evolution describes how these observed instances of evolution come about). The Big Bang is a (putative) event (and quite independent of the theory of evolution) that is largely compatible with and explained by the general theory of relativity. I would say evidence for the event is a bit more tentative than for evolution, but as a theory it has a huge amount of observational support - e.g. the cosmic microwave background. Both evolution and the Big Bang have vastly more supporting evidence than any competing theory, and neither has any unsurmountable difficulties, which is why they (or some more specific versions of them) have nearly universal support by scientists. --Stephan Schulz (talk) 14:52, 12 June 2019 (UTC) For the most part, true scientists DO look at the implications objectively and are prepared to be proven wrong and be willing to accept it. It's religionists who are generally unwilling to do likewise. ←Baseball Bugs What's up, Doc? carrots→ 15:04, 12 June 2019 (UTC) I agree with Baseball Bugs. What you are asking here for scientists to do is something that they regularly do, but in my experience is very rare when it comes to those who reject the Big Bang and evolution. Gnome de plume (talk) 15:49, 12 June 2019 (UTC) The user is a crusader, and crusaders don't last long on Wikipedia. ←Baseball Bugs What's up, Doc? carrots→ 15:50, 12 June 2019 (UTC) They are certainly welcome to have a civil discussion here with people like you and me though. Gnome de plume (talk) 15:53, 12 June 2019 (UTC) Follow their "contributions" for more insight. ←Baseball Bugs What's up, Doc? carrots→ 15:55, 12 June 2019 (UTC) "true scientist" are hard to distinguish beforehand. I even dare say there is science, that is, a way to properly do scientific work, but there are NO scientists. Remember that Newton, just like pretty much EVERY great scientist, was also a firm believer in very nutty ideas & disbeliever of very solid evidence (as we can see in retrospect; easier for us, dwarfs on giants shoulders). Richard Feynman lectures include the statement "Science is the belief in the ignorance of experts." (and by expert he meant scientists just as well). Just never trust anyone who says you must trust science and scientist, because, he is bullshitting you. Trust their achievement, trust the mechanics you see working, but don't them as "scientists" nor trust their holy scripture: this is just the very opposite of science. Gem fr (talk) 16:23, 12 June 2019 (UTC) Agreeing with all of the above, I would had that we trust theories insofar as they allow practical operation like, building objects, or, sailing west to reach far east place (this wont work on a flat Earth, only on a round/cylindrical one). Evolution theory, and all its modern development, include feat like genetically modified organisms. These exist and work. This is no proof that the theory is right, but this is enough of a confirmation to stick with it, and the theory just has no real problem to justify searching for alternatives (problem of the kind physics was struggling with, before Einstein papers). Big bang is just a mathematical development of the framework underlying general theory of relativity. We DO have lots of practical objects also relying on this theory (for instance, it is needed to synchronize clock on earth and clock on-board satellites, those having enough acceleration to produce time dilatation that must be reckoned with. There exist however legit alternatives to general relativity (see article for reason why). Gem fr (talk) 16:06, 12 June 2019 (UTC) I just realize we must have tons of archived answers about this question. I regret my previous answer Gem fr (talk) 16:58, 12 June 2019 (UTC) bingo. "evolution theory proof" turns 448 results in refdesk archive. same for "big bang proof": 282. Methink we should just delete the question. Gem fr (talk) 17:04, 12 June 2019 (UTC) No, that would mean you should include links so the OP can find them, not delete the Q. SinisterLefty (talk) 17:10, 12 June 2019 (UTC) As for evolution, there's no credible evidence that the theory is completely wrong, but there is room for some "tweaks". One somewhat recent tweak is that it seems evolution is not steady, but occurs in jumps and starts, spurred on by forces like a change in the environment, such as an ice age or competition with an introduced species (especially humans). An even more recent tweak is that it seems that some of our genes change over our lifetime, and are passed down, much as Lamark proposed, in an earlier version of evolution theory. See transgenerational epigenetic inheritance. The Biblical account of the creation of the universe and species, on the other hand, has massive proof against it, from fields as diverse as zoology, botany, biology, chemistry, geology, astrology, physics, archaeology, anthropology, linguistics, etc. The only way to make creationism compatible with science is to say that God(s) created the Big Bang and then just watched what happened. This is the Watchmaker analogy, but has nothing to do with what the Bible or other holy books say happened. SinisterLefty (talk) 17:10, 12 June 2019 (UTC) Lots of creationists have just zero problem conciliating Biblical account of the creation of the universe and species with evidence Gem fr (talk) 19:34, 12 June 2019 (UTC) Where religionism fails is that they start with the assumption that their scriptures are true, and anything that disagrees with that assumption must be ignored - or, if they're really desperate, declare that any evidence that contradicts their scriptural beliefs is "the work of the devil." As one of my old math professors liked to say, "If you start with invalid assumptions, you're liable to get 'interesting' results." ←Baseball Bugs What's up, Doc? carrots→ 17:24, 12 June 2019 (UTC) Yes, science is about following the evidence, wherever it leads, while religion is about cherry-picking only the evidence which supports your beliefs. SinisterLefty (talk) 17:28, 12 June 2019 (UTC) To be fair, lots of the "science" is ALSO about cherry-picking only the "evidence" which supports your beliefs. For instance, Marcellin Berthelot considered the atomic hypothesis superfluous, and, hence, to be rejected under Occam's razor; while this hypothesis was already more consistent with evidences, having doubt about it was still legit. At the opposite spectrum, string theory has believers, without any evidence it being necessary and quite a number of unsolved problems. Gem fr (talk) 19:00, 12 June 2019 (UTC) To be fair, science and religion to not cherry-pick. People do. While there are scientists who cherry-pick, and are heavily discredited for doing so, there are far more religious people who cherry-pick, and are considered more faithful for doing so. 68.115.219.130 (talk) 19:12, 12 June 2019 (UTC) Being scientist Vs being religious is not between people, it is inside each an every people. People who call themselves scientist are often acting as member of sect to defend the faith in their science (which may or may not be supported by evidence Gem fr (talk) 19:34, 12 June 2019 (UTC) Science is not in any way based on faith. If you believe so, you are not referring to science. You are referring to pseudoscience - such as astrology and homeopathy. 68.115.219.130 (talk) 19:42, 12 June 2019 (UTC) Well, not exactly. Science requires the faith that we can trust our senses and our instruments to make observations. ←Baseball Bugs What's up, Doc? carrots→ 21:29, 12 June 2019 (UTC)

I smelled this rat. Don't we have some kind of (polite; more polite that I would be...) RTFM, to redirect questions about relativity, evolution etc. to refdesk archive, where they were asked hundreds of time? Gem fr (talk) 22:24, 12 June 2019 (UTC)

It's been suggested from time to time that the ref desk should have a "frequently asked questions" page, with maybe something easier to navigate than the actual archives. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:28, 12 June 2019 (UTC)

Why not. But I was thinking about some kind of {{see also|whatever}} message to redirect toward this FAQ or to the search archive tool, that I currently miss (unless it exists, unbeknownst to me?) Gem fr (talk) 05:54, 13 June 2019 (UTC)

Perhaps a refdesk version of Wikipedia:Reliable sources/Perennial sources. Gråbergs Gråa Sång (talk) 08:06, 13 June 2019 (UTC)

I remember inviting the editor here (before they also started using their talk page as a blog). On the other hand, it's now obvious that they only seek to promote, not learn... —PaleoNeonate – 08:44, 13 June 2019 (UTC)

Bond survivability

In a James Bond novel (title in rot13: Zbbaenxre) Bond flees from the villain through steam pipes and survives by huddling inside them while the villain blasts hot steam (not convinced that Bond is in the pipes, but as a precaution). He's badly burned, but escapes and recovers in full in a hospital. Contrary to the movies, it seems to me that Fleming at least paid lip service to realism in the books, but surviving something like this still seems like a little over the top, considering how uncomfortable is even a waft of mere 100°C steam from a coffee pot. Are the any real chances of someone surviving an (I think) 30-second blast stuck to the sides of a (presumably hot) metal pipe, and being well enough to crawl off afterwards? 93.136.9.45 (talk) 23:15, 12 June 2019 (UTC)

According to [2], human survival in humid air is limited to minutes at 122^oF, so I'm gonna take a gander that if the air was hot enough to burn him, uh, no. Not if he's immersed in it, anyway - I never read the book. Someguy1221 (talk) 23:31, 12 June 2019 (UTC)

ROT13 is a simple letter-substitution Caesar cipher that is inadequate to obfuscate the 1955 novel title Moonraker. I claim the (presumed) prize for this decryption and invite the OP to pay it to the Wikimedia Foundation. DroneB (talk) 00:02, 13 June 2019 (UTC)

The idea of using rot13 in these situations is to provide spoiler protection while still making it easy for someone who wants to know the details to obtain them. It's a courtesy. It's not supposed to be deeply obfuscatory. --76.69.46.228 (talk) 03:35, 13 June 2019 (UTC)

Yeah, it was just to avoid spoiling the book. Sorry, DroneB 93.136.8.179 (talk) 19:42, 13 June 2019 (UTC) (OP)

first, while steam is hotter that water, and will release latent heat upon condensing, you must realize that it is gas, and as such as VASTLY less volumetric heat content that hot water for a simple mass question (the magnitude is ~10³ less). Steam is not the same hot scalding water. [3] hints at a few tens of seconds for second-degree burns to occurs on unprotected skin exposed to steam. If the victim has clothing (+protect his eyes etc.), surviving and even being fit to escape doesn't seem over the top to me if the exposure last a time you evaluate 30s or so (besides, we usually do not evaluate time properly, ~2-3x over/under estimate are frequent). The steam will replace oxygen, so you cannot breath; 30 s without breathing is not that a feat but is uncomfortable... Gem fr (talk) 07:35, 13 June 2019 (UTC)

Thanks, that sounds reasonable. Searching further I found Cave of the Crystals which says that ~60°C at 99% humidity can be endured for about 10 minutes. IIRC Bond pulled his shirt over his head to protect it, so he didn't have unprotected skin. 93.136.8.179 (talk) 19:42, 13 June 2019 (UTC) (OP)

• Bond isn't noted for technical accuracy, but Fleming had served as a naval officer during WWII and did have some familiarity with steam scalding accidents. Andy Dingley (talk) 08:28, 14 June 2019 (UTC)

June 13

Glasses Prescription

(This may seem to skirt on a "medical advice" question, but I am really interested more in the political aspect) I have worn prescription glasses for nearly 40 years. Every optometrist/optician I have ever visited (and there have been many), had this rule that they will not fill a prescription older than two years. But one day I broke my last pair, and an optician I was friendly with agreed to fill the prescription, even though it was three years old. He just shrugged, and said it was not a law, just more of an industry standard that was abided by to ensure continued business. Is that true, or is it actually regulated by some authority? If the former, it kind of seems like a type of collusion to me. Ditch ∝ 00:08, 13 June 2019 (UTC)

In the U.S., the expiration date for eyeglass prescriptions are set by state law (as opposed to drugs, which is set by federal law). See [4] - Nunh-huh 01:35, 13 June 2019 (UTC)

So it is regulated. That is extremely helpful, and answers my question, thank you! Ditch ∝ 02:13, 13 June 2019 (UTC)

You're welcome. It's regulated by some states; some other states just don't address it.- Nunh-huh 02:39, 13 June 2019 (UTC)

According to the FDA, spectacle lenses and frames are regulated as medical devices and are subject to certain federal regulations.

In fact, even non-prescription sunglasses are subject to regulation as a medical device, as described in this FDA publication Guidance Document For Nonprescription Sunglasses. One might opine that the degree of regulation, and the priority of enforcement, is commensurate to the administration's tendency toward non-interference when there is no real harm to a consumer; but the law still says that the products and the way that companies advertise and commercialize them must be in compliance with specified Federal regulations. For example, claims of protection from ultraviolet light have historically been scrutinized for scientific accuracy. See also, Is The Product a Medical Device? The textbook examples, often studied by law students, are the tongue depressor and the popsicle stick: outwardly, these are the same physical object, but when commercially marketed for medical use, the item becomes subject to 21 C.F.R. 880.6230.

This might seem heavy-handed to some observers - how and why would the Feds interfere with a simple eyeglass purchase? Everything in these rules becomes context-relative: if somebody commercially sells a plastic lens and tells you that it has corrective power to aid your eyesight, they need to be able to legally demonstrate that they have authority to make that claim (e.g. because they are appropriately licensed) and that the device functions as they claim (e.g. that they aren't selling fraudulent or harmful material). Money is being exchanged, it's interstate commerce even if the cats never leave the house, "...and here's why...", etc., etc., and therefore it also falls under Federal jurisdiction, unless they delegate those regulatory powers to local or state government.

Most of the time, FDA is too busy to care if somebody is selling counterfeit popsicle sticks, or operating an out-of-licensure expired-eyeglasses-prescription bootleg operation. However: if somebody does these things it somehow causes harm, rest assured that when the proverbial book is thrown, it lands with a heavy blow. And if you think expired eyeglasses are bad, just wait until you read about the lengthy prison sentences for mislabeling expired crabs. Statutory crab-expiry carries a greater Federal prison sentence than practical insurrection against the United States, which is bafflingly a Constitutionally-protected right.

Nimur (talk) 02:45, 13 June 2019 (UTC)

The Malheur occupation was maybe not the most representative example of "insurrection"; the charges were conspiracy to obstruct federal employees, firearms violations, theft, and damaging the refuge. No one was charged with insurrection, which is a crime under U.S. Code Title 18, Chapter 115. Some were convicted of the latter offenses. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)

Also, no offense intended, but while that's informative about issues surrounding federal regulation, it isn't really relevant to the question. Federal law, I believe, only sets expiration times for prescriptions for controlled substances, which eyeglasses are not. Otherwise, expiration is up to state law, as Nunh-huh noted. (I don't know how this works for territories or D.C. Would be interested if anyone knows!) Anyone wanting to learn more about U.S. medical device regulation may be interested in Medical device § United States and medical device design (which appears to only address the U.S. and needs editorial work). --47.146.63.87 (talk) 01:44, 14 June 2019 (UTC)

I apologize, I went a little overboard with my response. My point can be summarized: eyeglasses are subject to Federal laws that regulate medical devices; but the legal consequences of these rules are rarely visible to an end-consumer. Nimur (talk) 15:14, 14 June 2019 (UTC)

One issue is that you may require prescription lenses to drive safely, and if the prescription is old then this increases the chance that your eyes have changed and you now need a different prescription. --76.69.46.228 (talk) 03:37, 13 June 2019 (UTC)

But your ability to drive safely is the driver's legal responsibility, not the optometrist's. They may have a responsibility to warn (or even report) drivers with inadequate sight, after a test. But it would be far rarer for them to be required to pre-emptively screen everyone, on the grounds that the might be losing their sight. Andy Dingley (talk) 10:20, 13 June 2019 (UTC)

• I'm just saying that this sort of consideration might be what the people who made regulations such as we were asked about had in mind. --76.69.46.228 (talk) 18:43, 14 June 2019 (UTC)

besides, a hell of a lot of people drive with more than 2 years old eyeglass. Gem fr (talk) 15:06, 13 June 2019 (UTC)

But that's a risk taken by the patient, not the optician or whomever. If someone drove with old glasses, hadn't had an exam in years, and got in a crash, if they sued their optician, the suit would likely be quickly dismissed after showing the patient hadn't had an exam lately and had been given the standard advice to have regular exams. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)

Your argument might eventually win in court, but, especially in the U.S., medical professionals often practice defensive medicine to reduce the risk of being sued. Defending against a lawsuit is expensive, and, if you're required to carry malpractice insurance, will likely cause its premiums to rise substantially, as the insurer usually bears the cost of defending you against a malpractice suit. Refusing to fill old prescriptions costs you nothing other than potentially disgruntling some customers, and might even make money if you're part of a practice, as now the patient might get a new exam for a prescription. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)

• Local rules vary, but it's mostly a liability issue, rather than prescriptions. If you have a condition like glaucoma, that is usefully detectable by regular screening (in my country, the usual nominal fee for testing is waived if there's a family history). If you then went on to develop it, after visiting an optician but not having been screened for it, then that could be seen as a liability on their part. Andy Dingley (talk) 10:20, 13 June 2019 (UTC)

Agreed, see this from the UK National Health Service which has no profit motive except to save British tax payers' money:

"Glaucoma is usually picked up during a routine eye test, often before it causes any noticeable symptoms... It's important to have regular eye tests so problems such as glaucoma can be diagnosed and treated as early as possible. Early treatment can help stop your vision becoming severely affected. You should have an eye test at least every 2 years. National Health Service - Glaucoma - Diagnosis. Alansplodge (talk) 21:40, 13 June 2019 (UTC)

Yes, that's another factor: to kind of "force" people to get regular exams—although some might consider this slightly underhanded. Eye exams can often detect early signs of various diseases, such as diabetes. --47.146.63.87 (talk) 01:30, 14 June 2019 (UTC)

A boy went into a High Street opticians and underwent an eye examination. He had a condition where pressure builds up at the back of the eye. It is easily detected and easily treated. If not treated it proves fatal. The optometrist did not pick up the condition and the boy died. She was convicted of manslaughter. 2A02:C7F:A42:AD00:6D9E:CD5D:662E:5310 (talk) 17:47, 14 June 2019 (UTC)

Although she was cleared on appeal. [5] Andy Dingley (talk) 20:19, 14 June 2019 (UTC)

Gaining weight / losing weight

Generally speaking, gaining weight is accomplished by three things: (A) eating more food / calories (i.e., increasing calories consumed); (B) exercising / working out less (i.e., decreasing calories expended); or (C) some change in metabolism. Naturally, losing weight is the opposite. So, what exactly is the case when the side effect of a pill is listed as "weight gain" (or, conversely, "weight loss")? (A) The pill does not put food in your mouth or remove food from your mouth. Maybe it makes you more/less hungry? (B) The pill does not make you work out or prevent you from working out. Maybe it makes you more/less tired or more/less energetic? (C) Perhaps the pill has some effect on your metabolism? So, generally speaking, what does the pill do to your body that has the effect of you gaining/losing weight? Thanks. Joseph A. Spadaro (talk) 20:27, 13 June 2019 (UTC)

It would depend on the pill you're asking about. Perhaps a classic is thyroxine, which works to replace the hormone produced by an underactive thyroid gland. The thyroid produces thyroid hormone which regulates the metabolism. If it is underactive, the metabolism drops, potentially leading to weight gain. Taking the hormone to normal levels with an artificial replacement stops this and the weight might return to normal.--Phil Holmes (talk) 20:48, 13 June 2019 (UTC)

Thanks. But, that's not really what I had in mind. The thyroid, metabolism, and weight gain/loss are all closely interconnected and interrelated. If you are lacking thyroid hormone (due to an under-active thyroid), then the thyroxine pill simply brings you back to a "normal level". Hence, your thyroid becomes normal; your metabolism becomes normal; your weight becomes normal. My original question was referring to a pill totally unrelated to a direct cause of weight loss/gain. For example: "This pill for schizophrenia (or depression) has the side effect of weight gain/loss." Thanks. Joseph A. Spadaro (talk) 00:28, 14 June 2019 (UTC)

One of the issue with medication is that they have Side effect. Gem fr (talk) 03:02, 14 June 2019 (UTC)

A fundamental, relevant concept is that putting food in your mouth -> gut does not put nutrition in your tissues/organs. The gut is a tube that passes through us; only if the nutrients are absorbed will they provide nutrition - and various factors increase/decrease absorption of nutrients. Many foods need processing (physical and/or chemical change) in the gut before they can be absorbed. — soupvector (talk) 05:06, 14 June 2019 (UTC)

indeed. And many medication have a side effect on the working of the gut and its microbiota. Human_microbiota#Gut has a nice illustration of it. Gem fr (talk) 05:43, 14 June 2019 (UTC)

Some medications can affect appetite. Antipsychotics, I believe, can increase appetite. Many stimulant drugs decrease appetite, and are sometimes prescribed for this purpose. Note as well that manufacturers, agencies, etc. tend to err on the side of caution when listing possible side effects of medication. If trials of a drug showed a difference in something against the control group, this will get listed as a possible side effect, though it could be caused by something other than the drug, or just a fluke. Many illnesses can lead to weight changes, and determining whether something is caused by an illness or a treatment for that illness is tricky and requires studies specifically aimed at doing so, but those studies typically aren't part of the approval process for a drug. --47.146.63.87 (talk) 07:01, 14 June 2019 (UTC)

Voice detection

Can you detect a gay man by his voice and intonation?80.2.22.19 (talk) 22:51, 13 June 2019 (UTC)

Me, no I don't think I can but the article Gaydar notes acoustic analyses that found differences in how gay and straight men pronounce "s" sounds. DroneB (talk) 23:22, 13 June 2019 (UTC)

For additional stereotypes, see LGBT stereotypes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:38, 13 June 2019 (UTC)

Being gay (or not) won't prevent him to be detected by his voice, for sure. ;-) Gem fr (talk) 02:57, 14 June 2019 (UTC)

Media pushes a stereotypical voice for gay men. Some gay men recreate that stereotypical voice because media tells them that is how they should sound. Then, media uses those examples to justify their use of the stereotypical voice. In a feedback loop, it becomes more and more pronounced. So, some men, purposely or through years of influence, have a stereotypical "gay voice." Many do not. Some men who are not gay, also adopt the voice for whatever reason. This is not a "gay thing." It is just how media and society work. If you are black, you know that you aren't supposed to like anything with mayonnaise in it because media tells you that black people don't like mayonnaise. You don't want to be weird, so you accept it. If you are white, you know that you can't dance because media tells you that you can't dance. So, don't even try. There are many stereotypical feedback loops between media and society. Social media is making it far worse. 68.115.219.130 (talk) 11:24, 14 June 2019 (UTC)

Black people don't like mayonnaise? And I should just give up dancing because I'll never be any good at it? Gosh the things I learn from Wikipedia! ;-) Dmcq (talk) 13:37, 14 June 2019 (UTC)

for what this is worth, La Cage aux Folles (musical) feature a gay couple, one being the stereotypical drag queen, the other a man you wouldn't tell (even quite macho in the way he treats his spouse). Of course this is entertainment, not real, but the rationale is solid: gay men can mimic women, or just be the other guy. They say some do both, night and day. Gem fr (talk) 17:07, 14 June 2019 (UTC)

June 14

Long run equilibrium of infinite-dimensional open quantum systems

To start off, consider the simplest quantum system: a two-dimensional Hilbert space, or "qubit". The classical states are the 0 and the 1. If the system is isolated, then there exists a unitary time evolution operator which can be represented as a 2x2 matrix, e.g.

$U={\begin{bmatrix}a&b\\-b&a\\\end{bmatrix}}$

which acts on $|0\rangle ={\begin{bmatrix}1\\0\\\end{bmatrix}}$ and $|1\rangle ={\begin{bmatrix}0\\1\\\end{bmatrix}}$ and linear combinations thereof. The state of the system after n time steps is found by applying $U^{n}$ to the initial state.

For example, $U^{2}|0\rangle =(a^{2}-b^{2})|0\rangle -2ab|1\rangle$, and subsequently the probability of observing the system in the 0 state is $|a^{2}-b^{2}|^{2}$.

When the system is "open", the operator U "keeps track of the history". Denote the history of a state as a sequence of 0s and 1s, for example, $|*0\rangle$ is a sequence whose most recent state is the 0 state. Denote the new operator $U_{o}$.

Now, for instance, $U_{o}|*0\rangle =a|*00\rangle -b|*01\rangle$, and ${U_{o}}^{2}|*0\rangle =a^{2}|*000\rangle -ab|*001\rangle -b^{2}|*010\rangle -ab|*011\rangle$.

The difference is that $|*000\rangle$ and $|*010\rangle$, although both representing the 0 state, have different histories and therefore the probability of observing the system in the 0 state is now $|a^{2}|^{2}+|-b^{2}|^{2}$.

It can be shown that as you take $\lim _{n\rightarrow \infty }{U_{o}}^{n}$, the probability of observing the qubit in the 0 state (the sum of norm-squared probability amplitudes of all sequences whose most recent element is the 0 state) converges on ${\frac {1}{2}}$.

In fact, for a quantum system described by an m-dimensional Hilbert space, it can be shown that the probability of observing the system in any given state approaches ${\frac {1}{m}}$--all states are equiprobable in the long run.

What I want to know is what happens when the quantum system is described by an infinite-dimensional Hilbert space, such as a quantum field. Is the long run probability distribution of states still uniform in that case? My guess is that the answer is no, but that there is a long run equilibrium which is different from the uniform distribution over possible states.--49.183.144.209 (talk) 11:57, 14 June 2019 (UTC)

It depends on the system: you're asking about the long-range stability of a dynamical system, e.g. its Lyapunov stability; and this is a qualitative property that we can quantify only if we know the system equation - in other words, the time-evolution operator.

Whether the system is quantized, or not-quantized, you want to conduct stability analysis on the system equation; the quantization might introduce non-linearith into this analysis; but the methods are the same. It's a fascinating field, and there are a lot of open research questions. Wikipedia has articles on asymptotic analysis, a list of complex analysis topics; and so on that might point you in the right direction. I'm trying to think of a specific quantum mechanics book that has a section on stability-analysis - maybe I can recall a good one after checking the bookshelf. But I don't think you even need a quantum-physics book; even a book on linear systems - like Proakis & Manolakis - presents extensive mathematical analysis tools to help you prove whether an arbitrary system, representable as an operator with an infinite impulse response, converges or diverges asymptotically.

Unless the your operator implies that the individual elements interact with each other's values, it won't matter whether your state-space has one, two, or an infinite number of elements; their long-range stability depends on the operator only.

If the elements do interact, you've entered that branch of mathematics where the solutions depend strongly on tiny perturbations of the initial conditions.

Nimur (talk) 15:26, 14 June 2019 (UTC)

Thanks for your answer. I think the most important point is that the long range stability depends on the operator only, not the initial state. If I understand you correctly, you can form a unistochastic matrix from the 2x2 unitary matrix, and this unistochastic matrix can be interpreted as the transition matrix of a Markov chain, and it has an equilibrium distribution that doesn't depend on the initial state, and that remains true even if the state space is infinite.

What do you mean by "elements interacting with each other's values"?--49.183.144.209 (talk) 16:46, 14 June 2019 (UTC)

By "interactions" between elements, I mean to say that the system is coupled, e.g. a "coupled system of differential equations," or, in other words if the next transition of a state-variable depends on the value of a different state-variable. In mathematical jargon, this is true if and only if the matrix representation of the state-space transition equation contains non-diagonal elements. Here's Decoupling Systems, part of the Linear Systems class from MIT's math department; they describe a few methods of complex analysis that allow you to diagonalize any system of ODEs, or to determine that it is non-diagonalizable using only real (non-complex) solutions.

Then, to prove whether the system is stable or unstable, we can simply check if the magnitude of the real part of the diagonalized matrix is strictly less than unity.

This whole process has some kind of passing analogue in the mandelbrot fractal generator, which is itself an example of a test of convergence- or divergence- on one particular system's time-evolution operator. In that case, a system with two initial conditions (the real- and the imaginary- parts of c at time zero) can behave quite in a complicated manner, even though the time-evolution operator is almost trivial.

Nimur (talk) 22:30, 14 June 2019 (UTC)

Weight lifting question.

Is it bad to weight lift 2 days in a row? A lot of professional weight lifters like Bruce Lee do a Mon/Wed/Fri schedule or Tu/Th/Sat schedule. The logic is that muscles need 48 hours to heal. But what is the argument against weight lifting 2 days in a row? Because I also hear, weight lifting just makes muscle cells bigger, bu if you want new muscle cells to be created, you need to lift when you're sore, so that could be M/T and Th/Fr schedule. Shrug. 67.175.224.138 (talk) 15:41, 14 June 2019 (UTC).

This depends on how close to the limit you're exercising. If you're using the shocking method to lift yourself out of a plateau as Schwarzenegger explains here, then you'll need a larger resting period because a single bout of such an exercise session is going to be extremely intense. The next day you should exercise other muscles to avoid injury as the muscles you used yesterday won't be able to handle anything close to what you are normally used to. Count Iblis (talk) 16:22, 14 June 2019 (UTC)

I don't think that this question qualifies as medical advice, but it's nevertheless the kind of thing that you should consult a qualified person on. Get ahold of a professional trainer (pretty much every gym has them) to help direct your progress. You can definitely hurt yourself lifting incorrectly, but even without that, it's very likely that you won't get the desired outcome without the proper advice. I know a few semi-pros and they all swear by the advice trainers gave them. Matt Deres (talk) 22:35, 14 June 2019 (UTC)

Incandescent bulbs shining brighter

I stayed in a dorm when I went to university and each room had two desk areas, each with a desk lamp attached to the wall by way of an articulated arm. The bulbs were incandescent (this was in the 90s). Someone had heard of a neat trick involving such set ups, which turned out to be true. If you smack the shade of the light hard enough so that the entire system is shocked, the bulb will burn brighter - quite a bit brighter actually. None of us had access to a light meter, but I'd bet they were easily twice as bright. Unsurprisingly, some of the bulbs died shortly afterwards (I'll say, over the course of the next week or two), while others kept working fine for the rest of the semester. For whatever reason, that "experiment" recently came to my mind. What the heck was actually happening? I described the set up as best I can recall, in case that had something to do with it, but I presume the effect was caused by shocking the bulb itself...? When it gets right down to it, none of it makes much sense, but we - ahem - conducted several iterations of the test, almost all of which worked. Matt Deres (talk) 22:31, 14 June 2019 (UTC)

Coiled coil filament.

An Incandescent light bulb often has a coiled coil tungsten filament. When hot a mechanical shock could cause turns to weld together resulting in lower resistance and higher power since supply voltage is constant. DroneB (talk) 23:05, 14 June 2019 (UTC)

This question reminded me that as a kid I would try to "repair" clear glass, incandescent bulbs with broken filaments by turning them around and around until the broken ends crossed over. Applying power at that moment would cause a weld to occur, and the globe would work again. Never noticed whether the repaired ones were brighter or not. These would normally be single, "straight" wire filaments, not coiled ones. HiLo48 (talk) 00:13, 15 June 2019 (UTC)