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May 4

HSK taper

Machine_taper#HSK_taper says:

 The shank is short (about half as long as other machine tapers), with a shallow taper (a ratio of 1:10), and slightly too large to allow the flange to seat fully in the socket.

But the drawing right beside that paragraph shows a "1:9.98". Machine_taper#/media/File:DIN_69893_hsk_63a_drawing.png

Which is correct here?

Or maybe I'm misunderstanding something and that the two values are intentionally different. OptoFidelty (talk) 02:44, 4 May 2024 (UTC)

All the refs for current standards I see are 1:9.98. For that, "1:10" seems like a simplified approximation. I agree that we shouldn't make an approximation when stating outright what a standard is. DMacks (talk) 03:45, 4 May 2024 (UTC)

There was a hidden note that clarified it. I've unhidden it. Greglocock (talk) 02:13, 5 May 2024 (UTC)

May 8

Patient 18

Hi everyone, I hope that all of you are fine. Friends, I saw an interview on YouTube with a young man who is at a mental hospital in California (it was in 1961) and it's a famous interview. He has schizophrenia, and talks about his dreams of becoming a piano teacher.

My question is as follows, is his 1961 diagnosis still a criteria for commitment to a psychiatric facility? Have the laws/criteria changed?

Thank you and excuse ignorance, as I'm no professional on any of these fields. CoryGlee (talk) 11:15, 8 May 2024 (UTC)

The laws and their interpretations differ from jurisdiction to jurisdiction, but I think that the general principle is that involuntary commitment to a psychiatric hospital requires a determination that the patient is mentally incapable of taking care of themself or is a danger to themself or others. Many (perhaps most) people who are diagnosed with schizophrenia can nevertheless take care of their own affairs and present no danger to others.  --Lambiam 20:35, 8 May 2024 (UTC)

How short could the beta-decay half-life of a nuclide be?

Even the most neutron-rich nuclides like ¹⁹B has a half-life of >1 ms. Theoretically speaking, could a nuclide's beta-decay half-life reach <1 ms? Nucleus hydro elemon (talk) 11:55, 8 May 2024 (UTC)

It can, but extremally neutron rich nuclei tend to decay by emitting neutrons, which makes beta decay difficult to observe. Ruslik_Zero 12:08, 8 May 2024 (UTC)

Many nuclides are known with beta decay half lives under a millisecond. Thulium-180, to pick one example, decays 100% by beta- decay, and has a half life of 0.3 ms. If you want to explore the landscape, the table of nuclides here [1] is a good place to start. Anything in light blue decays primarily by beta- decay, and the farther you get from the central "valley of stability" the shorter the half lives tend to become. PianoDan (talk) 04:54, 9 May 2024 (UTC)

For a number of nuclides, though – including ¹⁸⁰Tm – the half-life has not been measured directly and only lower bounds have been reported. But there's nothing in theory that prevents beta decay with a half-life shorter than 1 millisecond, aside from competition from other decay modes. The shortest I've seen in {{NUBASE2020}} is a half-life of 1.5±0.5 ms for ³⁵Na, though that is only 1$\sigma$ from the 1-ms boundary. ^Complex/_Rational 15:14, 10 May 2024 (UTC)

May 9

LED lighting dimmer switch

Can you tell me about this? Does it it exist yet?

I now have parrot bird with red eyes and if you turn the light on from dark to light it drops him on his back. So I can't use LED bulbs in his room. Because previously I used a dimmer to bring light up gradually. Can you tell me? Thank you. Iqbal. 146.200.107.107 (talk) 02:15, 9 May 2024 (UTC)

Yes. They exist. I just went to the web site of my local hardware store, searched for "led dimmer switch" and found several. HiLo48 (talk) 02:25, 9 May 2024 (UTC)

There are also dimmable LED light bulbs that can be used with most types of dimmer.^[2]  --Lambiam 06:02, 9 May 2024 (UTC)

There are also led light bars that can be programmed for a gradually changing brightness and colour to simulate sunrise and sunset. Some even support simulating random clouds passing in front of the sun and the occasional thunderstorm with lightning. Aquarium lights tend to have such features. PiusImpavidus (talk) 12:13, 9 May 2024 (UTC)

Note that dimmable LEDs don't dim the same way incandescents do.

When incandescents dim, a lower level of power continues to be continuously conducted through the filament. The lower power produces less light.

LEDs don't really have variable brightness in response to different levels of power the same way incandescents do. Instead, they're dimmed by flickering them on and off at an extremely high frequency. The frequency is too high for our eyes/brains to perceive the flickering; but since they're not on all the time, less total light is emitted.

In order to respond to a decrease in power this way, the LED bulb needs to have specialized hardware in its base. So you'll have to buy special "dimmable" LED bulbs. I've had very mixed experiences with these, fwiw, and some that are nominally dimmable don't dim well or at all. Others produce extremely unpleasant light at lower levels. -- Avocado (talk) 20:33, 9 May 2024 (UTC)

Specifically, incandescent lights (is there anyone still using those? They've been banned in the EU for over a decade) can be dimmed by reducing the root-mean-square voltage over the filament. This lowers the light output, makes it redder and lowers the efficiency. Leds have constant colour and the brightness is controlled by electronically controlling the average current. Pulse-width modulation appears to be the simplest efficient way to control the average current. Dimmable led lights have some electronics that take the input voltage as a cue to change pulse width. Flicker is invisible to humans, but may appear when there's some beating with another periodic process of similar frequency (spinning things, cameras). A simple low-pass filter would eliminate the flicker. PiusImpavidus (talk) 07:54, 10 May 2024 (UTC)

Yeah, you can still buy incandescents in the US. They keep partially walking back the bans. And they're still allowed for specialty purposes (like heat lamps and candelabras), and maybe at low wattages? I've also recently seen incandescent bulbs with purportedly higher efficiency than old ones being sold in places -- I'd be unsurprised if our regulations are weak. And maybe leftover inventory is still allowed to be sold? Small retailers I think get them under the table from ... somewhere. If you search a major hardware store's site, you'll find a selection still for sale. Here's what we've got on the topic. -- Avocado (talk) 13:17, 10 May 2024 (UTC)

The flicker fusion threshold of birds is much higher than humans, up to 140 Hz (see this article). So a dimmed LED light that looks merely dim to us may appear to be flickering to a bird. I can imagine that that might be as unpleasant to a bird as a flickering light is to humans. Maybe some LEDs have a phosphorescent coating that absorbs and reemits the light after a delay, thus temporally buffering the light output, which might settle the parrot. Otherwise perhaps it is better to dull the light using a translucent screen or by reflecting the light off a surface. JMCHutchinson (talk) 11:43, 10 May 2024 (UTC)

Yeah, even as a human (hello, fellow humans!), I find dimmed LEDs to produce a very unpleasant light. I wonder if we can detect the flickering subconsciously even if we consciously can't? There's a theory that we can with fluorescents (which flicker even at full brightness), causing a bit of dysphoria in flourescent-lit spaces. -- Avocado (talk) 13:05, 10 May 2024 (UTC)

I have noticed that I can sometimes see flicker with peripheral vision that I can't when looking directly: aaand I see this is mentioned in the article. Flicker fusion threshold may also be of interest. {The poster formerly known as 87.81.230.195} 188.220.175.176 (talk) 14:57, 10 May 2024 (UTC)

Ambivert vs. omnivert

Is there a difference between ambivert and omnivert, or are these the same? 2601:646:8082:BA0:24BD:2FE2:B975:68AE (talk) 06:13, 9 May 2024 (UTC)

• Saucedo, Kayla (29 January 2024). "Ambivert Vs. Omnivert". simplypsychology.org. Simply Scholar Ltd. --136.54.106.120 (talk) 16:08, 9 May 2024 (UTC)

OK, thanks! So, an ambivert is someone who's near the middle of the scale all the time, whereas an omnivert is someone who goes from full extrovert to full introvert and everything in between? 2601:646:8082:BA0:CD56:E11E:9CF:F450 (talk) 02:45, 10 May 2024 (UTC)

Some researchers have questioned the validity of personality tests.^[3][4][5] I doubt that the validity of the specific labels ambivert and omnivert has been seriously studied; they may be pure pop-psych products. Also, even when valid, it can be questioned whether all this labeling isn't more harmful than beneficial.^[6]  --Lambiam 08:29, 10 May 2024 (UTC)

I hope you're not also questioning the validity of the labels extrovert and introvert, are you??? And if these are valid terms (which they are), then we also need a term for someone who's in the middle of the scale! 2601:646:8082:BA0:448D:8CB2:2FBC:B6C7 (talk) 23:19, 10 May 2024 (UTC)

Do we also need a term to label people who are halfway between introvert and omnivert? One problem with these personality tests is that they do not depend on a person's actual behaviour, but on their self-reported interpretation of their self-imagined behaviour in hypothetical, vaguely described situations. Validity as a personality label requires IMO consistent reproducibility over time, not of such self-reports, but of actual behaviour in a context of actual situations. I don't expect this stuff will be able to hold itself up well against the scientific method.  --Lambiam 06:34, 12 May 2024 (UTC)

Did you not read any part of this section other than your own comments??? First of all, as already explained above, the definition of omnivert is not that of someone occupying a certain position on the scale, but someone who fluctuates between extroversion and introversion, and hence there can be no "halfway" between omnivert and anything else! And as for the others, yes we do need specific terms for the far ends of the scale and also for the middle -- this is standard for any property which exists along a continuum! Also, I've personally taken both the ocean test and the MBTI test, and I can tell you, the situations described in the current versions are quite specific and mostly applicable to real life (at the very least, with the disclaimer that I'm one of the most pronounced introverts ever, I had no problems with the questions being "vague" or not applicable to me personally), so your criticism of these tests (at least in their current versions) is completely misplaced! And, as far as your demands for observation of "actual behaviour" (your emphasis, not mine), this would require a Big Brother-style system of constant and pervasive surveillance of your test subjects, which is completely impractical, highly illegal and unethical, and would itself introduce bias into your observations should your test subjects become aware of it (due to them modifying their own behavior to conform to perceived social norms out of fear of judgment) -- so, the stuff you propose wouldn't be able to hold itself up against the scientific method either (not to mention that it would most likely be disallowed on legal and ethical grounds)! 2601:646:8082:BA0:C178:97BE:AF93:9928 (talk) 09:41, 12 May 2024 (UTC)

You yourself wrote, "we also need a term for someone who's in the middle of the scale", i.e., between "the labels extrovert and introvert". This is what the term ambivert purports to signify. I responded to the claim of this need, wondering why there should be a need to label the extremes and one point in the middle, but not other points on the scale?  --Lambiam 20:12, 14 May 2024 (UTC)

Because then all of the other points on the scale can be visualized and described in relation to these 3 points -- whereas if only the two extremes were labeled, then it would not adequately describe those who are close to the middle! 2601:646:8082:BA0:BC05:6EA8:F933:9E6D (talk) 11:07, 15 May 2024 (UTC)

Not if they agree to it first, IP-hopper. As to this "omnivert" notion, it could be called "situational". Many people are more comfortable in certain settings than in other settings. That's "normal". ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:49, 12 May 2024 (UTC)

Maybe if they give fully informed consent it might be legal, but then you run into the other problem I mentioned (which you conveniently ignored) -- if they know they're being watched, they won't act like their normal selves (and the more you watch them, the more they'll put their guard up), so you won't see their "actual behaviour" in "actual situations", and you'll get skewed results! 2601:646:8082:BA0:28E6:4E7D:4BB4:DD49 (talk) 20:01, 12 May 2024 (UTC)

That would be tragic. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:51, 12 May 2024 (UTC)

That is just how people work -- and that is the reason why self-reporting of actual behavior is the best you can get in terms of data! 2601:646:8082:BA0:692F:1147:32D5:BCAA (talk) 01:54, 13 May 2024 (UTC)

Cultural anthropologists study actual behaviour. They don't go around handing out questionnaires.  --Lambiam 07:03, 15 May 2024 (UTC)

This is in the realm of psychology, though, not anthropology (cultural or otherwise) -- which brings up yet a third problem with your proposed methodology, that merely observing the behavior of your test subjects will not reveal what's going on inside their head at the time, and thereby also give you inaccurate results! (For example, an introvert like me might be forced against his/her will to attend an office party and even to mingle with other people thereat (and even to feign cheerfulness while doing so), which your methodology will register as extroverted behavior and will simply not see how miserable it makes him/her -- or, just to cover both sides, an extrovert might be forced to spend time working or studying alone, which your methodology will register as introverted behavior and not see how much he/she hates it!) And you still haven't answered how you would counter the observer effect (which, in this scenario, would manifest itself on a very macroscopic scale due to the fact that, as I already said, many people simply won't act like their own natural selves when they know they're being watched all the time)! 2601:646:8082:BA0:BC05:6EA8:F933:9E6D (talk) 11:07, 15 May 2024 (UTC)

And also, I see a fourth problem with this kind of methodology, and that has to do with sample selection bias -- introverts are far less likely to volunteer for an experiment in which their actual behavior would be monitored, especially if this includes being monitored inside their own homes, and the more introverted a person is the more likely he/she would refuse to take part in such an experiment (as an introvert from the deepest end of the scale, I personally know I would refuse without thinking twice), so you'll get a sample which is skewed toward extroversion, and that would also give you inaccurate or incomplete results! (This, indeed, is one area in which the current methodology of anonymous self-reported personality tests with hypothetical questions about various social situations is superior to any other suggested here -- there is something inherently reassuring about knowing that only me and the machine see the actual personal responses, especially for an introvert like me -- and this makes it better in terms of reducing sample bias than even self-reporting of actual behavior, because the latter cannot easily be reduced to a machine-processable series of multiple-choice questions and would require short-answer questions to be interpreted by a human psychologist, and knowing that an actual human sees your individual responses and your identifying data is much harder to swallow, especially given that being judged by a psychologist might (sometimes) have real-world consequences!) 2601:646:8082:BA0:2D37:9C1D:9DB2:251E (talk) 13:36, 17 May 2024 (UTC)

May 10

Insect repellent

Do all pyrethrin analogs have broad-spectrum insect repellent properties in less-than-lethal concentrations? 2601:646:8082:BA0:CD56:E11E:9CF:F450 (talk) 01:56, 10 May 2024 (UTC)

It says here that "Before the emergence of resistance, an early hut trial in The Gambia concluded that permethrin was the most repellent pyrethroid, followed by λ-cyhalothrin, deltamethrin, and lastly cypermethrin". This suggests that there must be some in the list of 29 examples in the pyrethroid article that are much worse repellents. I would guess that the stronger the odor, the better the repellent effect. Abductive (reasoning) 08:38, 10 May 2024 (UTC)

Pyrethroids were designed to kill insects and are used, for example, to control malaria-carrying mosquitoes by treating bed-nets. In this and other agricultural applications, repellence is an unwanted property particularly if the non-lethal effect allows insect populations to build up resistance. There are, of course, compounds designed to act only as insect repellents, of which the best known are probably DEET and citronellal. Mike Turnbull (talk) 10:46, 10 May 2024 (UTC)

Thanks! So, not all of them, but many of the common ones -- which is great for me (they're painting my front door today, so I have to enforce a no-fly zone outside it :-( ) And yes, last time I've personally witnessed the repellent effect of 200 ppm deltamethrin against Papilio multicaudata (or maybe it was a large P. rutulus, but my money is on the former) and P. eurymedon, as well as multiple Apocrita species! (The repellent effect, indeed, is what I'm looking for here -- I don't care if the bugs survive or die, I just don't want them to fly into the house or get anywhere near me!) 2601:646:8082:BA0:59E2:271:87C3:F3E (talk) 14:07, 10 May 2024 (UTC)

Also, one of the two cans I used today had a mixture of prallethrin and cyfluthrin which was specifically formulated as an insect repellent, so we can add these two to the list as well -- although, from personal observation, their repellent effect was actually less than that of deltamethrin! 2601:646:8082:BA0:448D:8CB2:2FBC:B6C7 (talk) 00:12, 11 May 2024 (UTC)

May 12

ecological spray bottle

does anyone know if there are any glass or metal spray bottles with bioplastic triggers and straw available anywhere in existence? i really want to go plastic free for my succulent business ninosckasnaturals.com 2600:1700:9758:7D90:B406:C016:3BC0:D48B (talk) 06:05, 12 May 2024 (UTC)

Maybe one of those old-fashioned perfume misters with the rubber squeeze bulb? I doubt very much that there is a mass-produced non-plastic alternative spray bottle apparatus. Abductive (reasoning) 21:49, 12 May 2024 (UTC)

There are pump-type plant misters (e.g. metal or glass). --136.54.106.120 (talk) 18:27, 13 May 2024 (UTC)

P.s.: LOOPSEED sells stainless steel plant mister spray bottles in various finishes, well-suited for succulents (search online for details). --136.54.106.120 (talk) 18:49, 13 May 2024 (UTC) -- [edit: 22:33, 13 May 2024 (UTC)]

origin of the formula for LC frequency

In electricity, properties known as inductance and capacitance together can resonate. The formula for the frequency of resonance is 1/(2*Pi*SQRT(L*C)). Who first published this formula? ```` Dionne Court (talk) 06:33, 12 May 2024 (UTC)

Somewhat after Laplace 1800 and before Poincarre, 1899 with a strong suspicion that the ubiquitous Maxwell might have done it. Greglocock (talk) 06:57, 12 May 2024 (UTC)

According to LC_circuit#History it was the ubiquitous Lord Kelvin in 1853. --Wrongfilter (talk) 07:10, 12 May 2024 (UTC)

Thank you. That man did everything. Greglocock (talk) 23:49, 12 May 2024 (UTC)

It does say that, but it is incorrect, which is why I posted here. Kelvin derived an equation to describe the transient response (response to a one-time shock excitation). However the article io LC_circuit#History gave as a reference an article in the Bell System Technical Journal, 1941, pages 415-453. I have now obtained this paper and it gives James Clerk Maxwell as the first to give the resonance formula (in a different but mathematically equivalent form), in a letter published in Philosphosical Magazine 1868. I will try and get this letter. ```` Dionne Court (talk) 03:13, 13 May 2024 (UTC)

It is this letter.  --Lambiam 12:14, 13 May 2024 (UTC)

It's from the right guy and via the correct other guy, but it has no math in it at all. It is not therefore the earliest statement of the resonance formula.

I'm looking for the fist statement of the formula as given in modern textbooks, i.e.,

f = 1/(2π(LC)^½).

It is a trivial exercise in algrbra to convert Maxwell's form into the standard modern form, but I would like to know when the modern form was first give. Dionne Court (talk) 00:29, 14 May 2024 (UTC)

The section entitled Mathematical Theory of the Experiment, an enclosure to the letter immediately following it on page 361, definitely contains some maths. On page 363 we see the equation ${\text{CL}}n^{2}=1,$ which results in an amplitude that, Maxwell writes, "is the greatest effect which can be produced with a given velocity". In this formula, the "velocity" $n$ is what is now more commonly denoted with the Greek letter $\omega .$  --Lambiam 06:49, 14 May 2024 (UTC)

p 540 onwards in Mathematical and Physical Papers, Volume 1 William Thomson Baron Kelvin University Press, 1882 - Mathematics - 619 pages, which is in google books, certainly discusses oscillatory behavior and time between peaks but I don't think it explicitly states f=1/(2pi*sqrt(L*C)). Particularly equation 7 where his A is modern L. Greglocock (talk) 00:08, 14 May 2024 (UTC)

May 14

Cranial size and Pb poisoning

Hello, can lead poisoning affect cranial size?Rich (talk) 05:43, 14 May 2024 (UTC)

Yes.^{[7] [8] [9]} --136.54.106.120 (talk) 11:40, 14 May 2024 (UTC)

May 15

They see me rollin', they hatin...

Question for you guys. Is there any animal whose primary method of locomotion is curling into a ball and rolling head over heels to get around? Rather than running or walking. Because I think some woodlice do it (faster for them to roll then run), but I'm not 100% sure. Iloveparrots (talk) 03:04, 15 May 2024 (UTC)

Do fictional animals count? --136.54.106.120 (talk) 03:33, 15 May 2024 (UTC)

Terrestrial locomotion #Rolling may be of interest. --136.54.106.120 (talk) 03:38, 15 May 2024 (UTC)

I don't see how that could ever be a primary means of locomotion, but see also Category:Rolling animals. Shantavira|^{feed me} 08:37, 15 May 2024 (UTC)

Hedgehogs do it to escape from predators when threatened. 2601:646:8082:BA0:BC05:6EA8:F933:9E6D (talk) 10:43, 15 May 2024 (UTC)

Hedgehogs roll up for protection, not for locomotion. (Ditto for the woodlice mentioned by the OP). Iapetus (talk) 11:57, 15 May 2024 (UTC)

I don't think I've ever seen a hedgehog roll outside of a video game. But then again, I've only ever seen hedgehogs in real life about three times. Iloveparrots (talk) 22:58, 15 May 2024 (UTC)

Hedgehogs do not purposely roll when in a defensive ball. They "huff", which makes them bounce, forcing their quills into whatever is attacking them. That bounce could cause a roll, but it isn't on purpose. 75.136.148.8 (talk) 13:40, 16 May 2024 (UTC)

See Rotating locomotion in living systems. 2605:B100:34D:46C3:61A4:6B17:A082:3780 (talk) 12:27, 15 May 2024 (UTC)

I have encountered assertions that Giant pandas, when sitting in a bamboo thicket on a slope, will sometimes roll a short distance rather than get up and walk, but this would need confirmation from a reliable source, and in any case would not be a primary means of locomotion. {The poster formerly known as 87.81.230.195} 94.2.67.173 (talk) 19:48, 15 May 2024 (UTC)

A giant panda is rolling head first in this video: Panda Discovers Something Interesting. They roll about a lot too, for various reasons. Modocc (talk) 23:30, 15 May 2024 (UTC)

What's the max depth of the Baltic, Black and Azov brim?

The depth where it stops being connected to the World Ocean 50% of the time (connected only by seepage through porous solids like silt not counting as connected). As the brim can erode, shift if the water's removed, be a V-notch in a ridge etc and even if it's dredged wide, straight and flat it might not be legal to lightly touch the silt so this might not round to the same number of feet as the deepest draft ship that's allowed at least 50% of the Metonic cycle, or how much sea level would have to drop to make it a lake 50% of the time. Also what would the depth be if the strait bottom wasn't landscaped? The Turkish Straits are pretty deep by ship standards maybe they aren't landscaped? Sagittarian Milky Way (talk) 18:05, 15 May 2024 (UTC)

They wouldn't need to be "landscaped", the Bosphorous is typically about 60 m deep with a 40 m sill towards its southern end, although the Asian side of the strait at that point is somewhat shallower (about 27 m) - see Siddall et al. (2004). Mikenorton (talk) 19:11, 15 May 2024 (UTC)

Right I didn't think they would. Unless the depth of the rim's now artificial by more than a foot due to sinking accidents(s), full or partial intentional blockages or explosion(s) (possibly to clear some of the previous)? Or maybe it's still the natural rock or sediment accumulation-erosion surface? I don't know if the Baltic and Azov brim are unaffected by human landscaping. Sagittarian Milky Way (talk) 20:16, 15 May 2024 (UTC)

May 17

What would cause these 'dark area' blemishes on an LCD monitor?

See this photo: https://ibb.co/mz8vQh0

This is my Asus Designo MX25AQ main monitor, I've had it for a little over four years and two months now. Since about a year ago, it started developing this issue where a "wavy" area of darkness appears near the left and right edges of the screen. It looks as if there's liquid in the screen or if something's "delaminating" inside. It would usually happen when it's cold, and would go away / "fade away" as it warmed up (usually taking a few minutes). However, over the last few months, it's been getting worse and worse. Nowadays, sometimes it's visible on certain shades of colours even when the monitor is fully warmed up. It is especially noticeable when it cools down in real life (e.g. it's becoming dawn and the brightness has been decreased).

The "grey uniformity" of the monitor has been degrading a bit as well, I swear.

I know I likely won't be able to fix an issue like this with the LCD panel. But my question is, what would possibly cause these issues? Could it develop into a stage where my LCD becomes completely / severely broken?

Note that I'm posting this to RD/S and not RD/C because I strongly believe this issue has something to do with materials degradation in the LCD and not some issue with the computer or cable, so I figured this is a better place for that.

Apologies for the non-free external image site upload, but if everything you see in the photo is not copyrighted then I will upload it to Commons. — AP 499D25 (talk) 05:03, 17 May 2024 (UTC)

I Googled around, and it could be moisture infiltrating around the edges. The fact that it clears when hot is suggestive of that. There was a suggestion that if the monitor is near a kitchen, these stains could include cooking fumes. Another possibility (and conceivably related) is damage from pulling the protective plastic sheet off, the one that came when the monitor was newly purchased. This has to be done extremely carefully. Yet another worry is cleaning with rubbing alcohol, the internet says this is a bad idea. Abductive (reasoning) 06:11, 17 May 2024 (UTC)

Rubbing alcohol as sold can consist for up to 50% of water.  --Lambiam 09:16, 18 May 2024 (UTC)

That sounds plausible! Thinking about it, more than a year ago I did clean my monitor using a wet microfibre cloth (a small, thin one for phones), and that seems to be the timepoint it all started. Worth pointing out that this monitor is in a bedroom, so it's not near moisture or oil vapour sources, and it has never been used in such an environment. When I got it new, there wasn't actually a protective sticky film on the front, just a styrofoam wrap. When I slid that wrap off, I got a nice big static shock when I touched the monitor bezel, but that didn't seem to do any immediate damage – this monitor was fine for the first 2.5 years or so that I used it.

Another interesting fact about this monitor is that although I bought it in Mar 2020, according to the info label, it has an manufacture date of Sep 2015, so that means it sat in a warehouse for 4.5 years before I bought it I guess.

Aside from this annoying and distracting issue, this monitor is the best quality display I've ever had (QHD resolution and 100% sRGB accuracy), so it'd be such a shame if it's actually dying on me. — AP 499D25 (talk) 08:06, 17 May 2024 (UTC)

Is there any scientific truth to the meme that Vegetable oil/Seed oil is toxic to the human body?

There are plenty of memes that seed oil causes diabetes and heart attacks but I failed to find any wikipedia articles that argues their case. Is there any scientific truth to the meme that Vegetable oil/Seed oil is toxic/harmful to the human body?

Another question is that if the meme of harmful seed oil is unscientific then why isn't this meme documented in the List_of_conspiracy_theories wiki page? 2001:8003:429D:4100:A593:8A5B:182E:5551 (talk) 15:55, 17 May 2024 (UTC)

Any kind of fats or oils in excess can cause heart disease, but there is no truth to the claim that vegetable oil is more toxic than animal fats (in fact, it's actually healthier) or that its consumption in moderation causes any health problems. 2601:646:8082:BA0:9480:50AE:ABF3:5E17 (talk) 23:30, 17 May 2024 (UTC)

Yes, there is truth to it. Our nutrition articles could do with some updating and balance. It is a prime example of Paracelsus's The dose makes the poison, for both the omega 6 LA and omega 3 ALA are essential nutrients for humans. The basic issue is consumption of a high quantity of omega-6 fatty acids from modern seed oils (which have only been consumed for a century or so) and other sources, including indirectly through animal feed and the (relative) paucity of omega-3 fatty acids in the modern human diet. [Excessive omega-3 over omega-6 has been found only in Greenlandic Inuit traditional communities.] Probably the best book to start with is Anthony John Hulbert's recent Omega Balance: Nutritional Power for a Happier, Healthier Life- Johns Hopkins (2022). By omega balance, he means the percentage of omega 3's in the sum of omega 3's and 6's. He says:

Although there is no advice about separate consumption of omega-3 and omega-6 fats in these national dietary guidelines, this is not the case with the premier scientific society concerning lipid research. In 2004, ISSFAL (International Society for the Study of Fatty Acids and Lipids) issued a series of recommendations for dietary intake of the essential fats by healthy adults. They made no comment about consumption of the nonessential saturated and monounsaturated fats but instead proposed that adequate intake of 18:2ω-6 [ Linoleic acid (LA) ] is 2 percent of energy, and a healthy intake of 18:3ω-3 [ α-linolenic acid (ALA) ] is 0.7 percent of energy as well as recommending a minimum intake of 500mg/d of 20:5ω-3 [ eicosapentaenoic acid (EPA)] and 22:6ω-6 [sic, should be 22:6ω-3 docosahexaenoic acid (DHA) as in the source [10]]. These ISSFAL recommendations for daily intake correspond to a diet omega balance of about 30 percent. The recommended intakes contrast markedly with the average actual daily intakes by the US population (from a 1999–2000 survey), which correspond to a diet omega balance of 9 percent. Similarly, a dietary survey of the Australian population revealed the average daily intake in 1995 corresponded to a diet omega balance of 11 percent. Both the United States and Australia (and likely many other developed high-income countries) have omega-6 intakes much higher and omega-3 intakes lower than the recommended levels.

Hulbert and other sources provide evidence that the omega imbalance can have deleterious effects not only in various chronic diseases, but also that the excess of inflammatory omega-6's can worsen outcomes of Covid, where many deaths appear to come from an excessive inflammatory response.John Z (talk)

μ-Oxidodihydrogen, a chemical compound found in industrially processed canned soup, is also known to be toxic to the human body. Why is no one talking about this?  --Lambiam 09:10, 18 May 2024 (UTC)

Butterfly size

Do butterflies (especially nymphalids and/or swallowtails) become significantly smaller in size near the poleward (high-latitude) limit of their natural range? When I visited the Royal Ontario Museum in Toronto, they had 2 pinned specimens of Papilio cresphontes on display which were much smaller than their normal size per the article (one had a wingspan of "only" 3 inches -- I did a rough measurement with my fingers against the glass -- and the other was about 1/2 inch bigger) -- is this normal for (1) specifically P. cresphontes, (2) all swallowtails, and/or (3) all or most butterfly species? 2601:646:8082:BA0:9480:50AE:ABF3:5E17 (talk) 23:38, 17 May 2024 (UTC)

Size Distributions of Butterfly Species and the Effect of Latitude on Species Sizes (you can open a free JSTOR account or access through the Wikipedia Library). Alansplodge (talk) 10:10, 18 May 2024 (UTC)

Sorry, I won't click on any external links regarding this topic, just in case it might show me gratuitously enlarged pictures of P. multicaudata or some suchlike abomination -- can you just tell me the gist of it in a few words (or more than a few, your choice)? 2601:646:8082:BA0:E558:16C8:D2DE:51EF (talk) 10:31, 18 May 2024 (UTC)

There are no pictures, it's a scientific paper. "For butterfly species (Papilionoidea) of the Australian and Afrotropical regions, average wingspan decreases with increasing latitude". Alansplodge (talk) 10:34, 18 May 2024 (UTC)

May 18

Why packaging is important

Two reasons why packaging is important PhuPhumzile (talk) 07:10, 18 May 2024 (UTC)

Please do your own homework.

Welcome to the Wikipedia Reference Desk. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. Shantavira|^{feed me} 09:16, 18 May 2024 (UTC)

• Read our article on "Packaging". It may assist you. Graeme Bartlett (talk) 09:40, 18 May 2024 (UTC)

Ya gotta love it when a poster doesn't even try to make it look like a question they thought of on their own. Or like a question, even. ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:23, 18 May 2024 (UTC)