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February 19

The Maimonides position about the semen and intercourse is supported by the science?

I came across Mimondes' position about semen and intercourse, and it is interesting for me if it is supported by science, or it is anachronistic and not up to date? Here is what he says (Human dispositions 4,19):

"Semen is the strength of the body, its life [force], and the light of the eyes; the greater the emission [of sperm], [the greater] the damage to the body, to its strength, and the greater the loss to one's life [span]. This was implied by Solomon in his wisdom: "Do not give your strength to women" (Proverbs 31:3 . Whoever is steeped in sexual relations, old age springs upon him [before its time], his strength is depleted, his eyes become dim, a foul odor emanates from his mouth and his armpits, the hair of his head, his eyebrows, and eyelashes fall out, the hair of his beard, armpits, and legs grows in abundance, his teeth fall out and he suffers many pains beyond these. The wise of the doctors have said: One of a thousand dies from other illnesses and a thousand from excessive intercourse."

--ThePupil (talk) 01:15, 19 February 2023 (UTC)

We don't seem to have an article that character. But it sounds like he was the inspiration for General Jack Ripper. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:59, 19 February 2023 (UTC)

The "character" is Maimonides, the passage is from Mishneh Torah. I've had some difficulties trying to understand the structure of the thing, but it appears to be in the first book (HaMadda), section 2 (De'ot), and there in the 19th paragraph of chapter 4, see e.g. [1] or [2]. --Wrongfilter (talk) 09:35, 19 February 2023 (UTC)

It helps when the OP spells it right. Well, that's an interesting read. On some things he may be right, on others he missed the boat. ←Baseball Bugs ^{What's up, Doc?} carrots→ 10:13, 19 February 2023 (UTC)

(ec) No, this is not supported by science -- frequent sexual intercourse does not, in and of itself, harm the body (unless one catches venereal disease, which is a different matter altogether!) 2601:646:8A81:6070:21B3:46A0:D94F:FF3B (talk) 02:04, 19 February 2023 (UTC)

Oh, and for evidence, see Sexual_intercourse#Health_effects. 2601:646:8A81:6070:21B3:46A0:D94F:FF3B (talk) 02:07, 19 February 2023 (UTC)

While Maimonedes was surprisingly scientifically enlightened for the 12th century – the various authors of Proverbs (Ch 31 vv 1–9 are attributed to Lemuel (biblical king), not Solomon) in the 1st millenium BCE perhaps less so – such pronouncements around sexual activities are almost invariably concerned with social and moral control, rather than literal medical facts. Did your parents ever tell you that eating pure sugar gives one worms, or sitting on a radiator gives one piles? (Mine did.) Did you believe them then, and do you believe it now? {The poster formerly known as 87.81.230.195} 51.198.55.125 (talk) 02:39, 20 February 2023 (UTC)

I never did reconcile "sitting on a radiator gives one piles" with "sitting on a cold stone wall gives one piles"! Perhaps they just didn't like boys sitting down? Goes along with "don't share caps or you can catch dandruff". Martin of Sheffield (talk) 08:01, 20 February 2023 (UTC)

Reconciled with: prolonged sitting. Shantavira|^{feed me} 09:34, 20 February 2023 (UTC)

IMO Sexuality and superstitions is a good topic seems yet to be covered on WP Bookku (talk) 10:48, 20 February 2023 (UTC)

WP:WHAAOE: religion and sexuality. Tigraan^{Click here for my talk page ("private" contact)} 14:02, 20 February 2023 (UTC)

Maimonides had many interesting things to say, some of them wise. This particular thing was nonsense. I have followed the exact opposite of his advice for 55 years or more, and I am in good health and several years older than Maimonides when he died. Frequent orgasms are good for human health. Cullen328 (talk) 08:37, 23 February 2023 (UTC)

February 20

Recent Chinese UFO

Regarding this footage, did any reliable source offer a plausible explanation? Particularly, could it be a video manipulation and if not, what aircraft or natural phenomenon can produce such pattern? 212.180.235.46 (talk) 19:30, 20 February 2023 (UTC)

Looks to me like something pretty simple, such as countermeasure flares. Maybe the People's Liberation Army Air Force was doing some sort of training exercise over the area. As for what aircraft could produce such a pattern, basically any military aircraft could potentially do that, as long as it is fitted with flares. --OuroborosCobra (talk) 20:22, 20 February 2023 (UTC)

If it is a military aircraft throwing flares, as seems likely, its nearest base is at the dual-use military/civil Qiqihar Sanjiazi Airport. Philvoids (talk) 23:45, 20 February 2023 (UTC)

The flares are fired to the side rather than just left in the aircrafts path in any pictures I've seen. They don't seem to go off the path in the video. NadVolum (talk) 16:57, 21 February 2023 (UTC)

That differs depending on the aircraft. In the video, I do seem to observe some amount of spread, though admittedly not much. Larger aircraft, like cargo planes, tend to shoot them out to the side (or both in line and out to the side). Smaller aircraft, like fighters, tend not to release to the side. This image of a Chinese J-16 looks to me like what we see in the video, an overall strait line flare release, with a small amount of spread. --OuroborosCobra (talk) 17:07, 21 February 2023 (UTC)

February 21

Thyroid pills

Not seeking medical advice. Question is inspired by just seeing a TV show involving someone with Hashimoto's disease. The person explained that this is an autoimmune disorder where the body attacks the thyroid gland, and this is bad because without a thyroid gland, you will die! But I know that thyroidectomy is a thing, and that the person usually has to thyroid pills for the rest of their life afterwards, but assuming they take their pills it's not that terrible in the scheme of things.

My question is what happens if the person doesn't take their pills, such as due to a supply interruption? Do they get symptoms if they miss one dose? What if they miss it for a week or a month? If they miss enough to become seriously ill, does the illness reverse once they are back on the drug? And is someone with Hashimoto's (assuming they are getting appropriate treatment) somehow in worse condition than someone who has had their thyroid removed outright?

My mom takes some prescription meds (not thyroid related) and regularly experiences hassles because the prescription has run out of refills (requiring new prescription requests to her doctor, which can take a while to get handled), and that sort of thing. In my mom's case, those occurrences have been annoying but not really dangerous. I'd like to think anyone with critical dependence on a drug should keep a very large supply on hand, but the dispensing system seems set up to prevent this. Thanks. 2601:648:8200:990:0:0:0:756C (talk) 00:52, 21 February 2023 (UTC)

See our article Hypothyroidism. Graeme Bartlett (talk) 00:55, 21 February 2023 (UTC)

Thanks, will look there. 2601:648:8200:990:0:0:0:756C (talk) 00:55, 21 February 2023 (UTC)

Goldfish size

I heard that goldfish keep growing throughout their life if you put them in a large enough tank with the right conditions and food. Is this true? If so, why would they stop growing in other cases? 135.180.244.18 (talk) 05:28, 21 February 2023 (UTC)

Googling the subject, this appears to be true of fish in general, and also for other cold-blooded creatures such as reptiles. This is also true for various types of trees.[3] ←Baseball Bugs ^{What's up, Doc?} carrots→ 08:18, 21 February 2023 (UTC)

Not surprisingly, we have an article Goldfish which goes into some detail about this. {The poster formerly known as 87.81.230.195} 51.198.55.125 (talk) 08:25, 21 February 2023 (UTC)

Why the 15 incher was conducting a population survey, we'll never know. Clarityfiend (talk) 16:48, 21 February 2023 (UTC)

February 22

Graphic equalizers with perceptual frequency scale

Last time, I made the graphic EQ that use arbitrary frequency scale for spacing center frequencies. So the question is why most graphic equalizers have logarithmic frequency scaling in regards to spacing for center frequencies? And is it better to use 24-band Bark scale than typical log2 and 1/3rd octave spacing for GEQ since our hearing is actually linear at bass and logarithmic at anything else? 2001:448A:3042:7FD9:75AE:9537:3A9B:A23F (talk) 03:15, 22 February 2023 (UTC)

You also have to look at the effort for the operator to apply the settings. It should not be too many frequencies, otherwise it probably will not be set optimally , and if it was, there would be a lot of slider pushing. If you were using linear spacing, for high frequencies there would be far too many that could not be easily separated audibly. Also for the electronics, it is going to be much easier to make a algorithmically spaced set of controls, as the circuitry is going to be as simple as possible, without having a high-Q, with narrow bands. Graeme Bartlett (talk) 11:14, 22 February 2023 (UTC)

Most graphic equalizers have logarithmic spacing of center frequencies for the same reason my piano does. See A primer on graphic equalizers. Equalizers are used to modify music and here the human perception of pitch is well modelled by the Mel scale which is a logarithmic function of frequency. Aural discrimination of frequency occurs in the Cochlea of the inner ear. Each piano key maps to a position along the cochlea, bass notes deepest. I confirm that a semitone step at the lowest or the highest end of my piano sound similar, so the correctness of the logarithmic frequency model is apparent, at least to this western music listener. A graphic equalizer has a number of adjustable FIR (Finite Impulse Response) filters that typically varies from 7 on a domestic or in-car unit (center frequencies 60 - 150 - 400 - 1kHz - 2.4kHz - 6kHz - 15kHz), to 10-band (octave step), 15-band and 31-band (1/3-octave step) professional units. An extreme graphic equalizer with 88 steps duplicating each piano key in the Equal temperament scale of successive 2^1/12 ratio frequency steps could be built though I don't see a need for it. An operator may use a graphic equalizer to shape the sound power distribution in frequency to achieve various effects or to compensate for room acoustics and/or for the non-linearity of ear sensitivity which is always quantified on logarithmic frequency scales such as Robinson–Dadson curves (1956) or Fletcher–Munson curves (1933). I can't support the OP's implication that human hearing changes from logarithmic to linear near a bass music extreme such as piano A₀ 27.5 Hz. Graphic equalizers intended for other purposes than music may have different frequency step allocations. A device that lets you choose your center frequency, narrow or widen the bandwidth of surrounding frequencies that are affected, and also adjust the slope of those frequencies is called a parametric analyzer and is likely to use second‑order IIR (Infinite Impulse Response) filters. Philvoids (talk) 17:06, 22 February 2023 (UTC)

@Graeme Bartlett and Philvoids: In regards to the effort for the user to apply settings to EQ curve, while its true it takes a lot of effort to change a frequency curve of 120-band GEQ (which I don't see the need for it) given the fact adjusting the sliders takes time (maxing out first 2 bands on 10-band equalizer or first 5 bands on third-octave EQ to get a bass boost effect), I would agree that using different frequency scale affects the resolution and the amount of effort tradeoff for each frequencies; logarithmic frequency scale provides equidistant spacing on the same frequency scale as note frequencies (however, the bass frequencies will suffer from pre-ringing artifacts when it is in linear-phase mode as auditory perception is linear at bass frequencies and logarithmic at anything else, same goes for time resolution on constant-Q transform visualizations), while setting to linear frequency scale definitely gives too many control on higher frequencies and too few on bass frequencies. Most if not all frequency scales modeled on auditory system are approximately linear at bass frequencies and logarithmic at higher frequencies, so the resolution for a 24-band GEQ spaced on a Bark scale is somewhat in-between 7-band GEQ for the bass frequencies and slowly transitioning to 31-band one for higher frequencies. For the regards to EQ types, the parametric EQ is for anything precise and this is something that isn't being used often on casual listeners while commonly-used graphic EQs are easier to control as all the user have to do is just adjust the curve until the user found out the pleasant curve. Also, the FIR filters doesn't have to be linear-phase and most graphic EQs actually use IIR filters and the frequency response sometimes isn't perfectly flat when all bands are set to minimum or maximum value. 2001:448A:3046:59C8:693C:6C8F:8FD2:B68 (talk) 00:40, 23 February 2023 (UTC)

Chemistry

What is electrolyte — Preceding unsigned comment added by 129.0.99.165 (talk) 15:14, 22 February 2023 (UTC)

I think the article on oral rehydration therapy may be more useful than the electrolyte article. Abductive (reasoning) 15:34, 22 February 2023 (UTC)

Maybe so but see Electrolyte. An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Philvoids (talk) 17:13, 22 February 2023 (UTC)

Movie trivia
The following discussion has been closed. Please do not modify it.
It's NOT what plants crave. Or at least they'll tolerate pouring one drop per millennium of Gatorade, Powerade, Brawndo and similar drinks but if you keep increasing that amount at some point they die. Sagittarian Milky Way (talk) 19:17, 22 February 2023 (UTC) What is going on with this question? Sorry for bolding/shouting, but the responses to this question are really making me wonder what exactly is expected for behavior on this reference desk? The IP asked a very simple definitional question. The first response suggests something that may be entirely unrelated as nothing in the IP question implies they are asking about sports beverages or anything that we would consume. The second answer, from Philvoids, actually seems like a good answer to the question. Then we have a third and completely random, to the point of being a non-sequitor, going off on a tangent about watering plants with Gatorade. Was anything involving plants even in the IP question, or any subsequent responses before that? Nope. So what is going on here? --OuroborosCobra (talk) 23:59, 22 February 2023 (UTC) https://www.imdb.com/title/tt0387808/ Sagittarian Milky Way (talk) 00:14, 23 February 2023 (UTC) That's not an answer to my question, and if you were trying to mimic that movie, I'm again asking what are we doing here? Is your purpose here to dumb things down to nonsense with your answers to questions? --OuroborosCobra (talk) 00:20, 23 February 2023 (UTC) It's a funny comedy about a millennium-long reverse Flynn effect starting in the near future allowing 2 ubiquitous sports drink slogans to persuade USA to convert all tap water systems and irrigation to more profitable drinks causing soil electrolytes to rise till an average Joe of 2006 (botched suspended animation experiment) convinces the government to irrigate with water so America doesn't starve to death. Which takes a whole hour cause Brawndo's What Plants Crave! and It's Got Electrolytes! After an hour of using logic and reason Joe gave up and told everyone that he could talk to plants and they wanted water and that convinces them. Sagittarian Milky Way (talk) 01:33, 23 February 2023 (UTC) So you are trolling legitimate questions on this reference desk. Cool. Again, why are we here? --OuroborosCobra (talk) 15:45, 23 February 2023 (UTC)

How close to men being irrelevant?

I'm curious how close science is to being able to taking two cells (either Monoploid like eggs or Diploid "normal cells") from Mammalian females and producing a viable cell with the genetic material from both females that can grow to adulthood? I don't have a good feeling for where we are on the scale of A) "They did it with mice last year, cows last month and Gibbons are scheduled for April" to B) somewhat more difficult than Star Trek Warp Drive. Naraht (talk) 19:06, 22 February 2023 (UTC)

You'd need artificial Y chromosomes to make cismen. Unless you have a transgender human (no transmen, that won't work). Sagittarian Milky Way (talk) 19:24, 22 February 2023 (UTC)

We could clone humans right now. All the males could die (or all but a rather high number (up to thousands) of random fertile men plus all other males which would mean death by genetic bottleneck without technology) and they could do the Dolly the sheep thing. _{I don't know if it's possible for the clone to not die quickly young like Dolly. But even if clone life expectancy is full-blown "life expectancy of donor at donation minus age of clone since conception" then if the lady is 18 the clone would probably have at least a few decades of adulthood.} Sagittarian Milky Way (talk) 20:45, 22 February 2023 (UTC)

As far as we know, cloned sheep do not have a reduced lifespan. Dolly died of an illness that appears unrelated to having been cloned.  --Lambiam 22:34, 22 February 2023 (UTC)

If you're interested in reading about specific examples to see outcomes, we have List of animals that have been cloned and Category:Cloned animals. DMacks (talk) 22:40, 22 February 2023 (UTC)

My mistake. Why do I even remember generation old wrong hypotheses? Sagittarian Milky Way (talk) 22:47, 22 February 2023 (UTC)

See [4] Nil Einne (talk) 05:13, 23 February 2023 (UTC)

The technique would be similar to that used in cloning, but would be different in detail. In cloning, the nucleus of an oocyte is removed and replaced by that of a stem cell of the donor. In what you are proposing, the nucleus of the recipient oocyte would not be removed, but that of a donating oocyte would be added. I don't know if this has been attempted.  --Lambiam 22:44, 22 February 2023 (UTC)

Girl Child of two Female

OP here. I am *not* talking about cloning a single individual. I am talking about creating a female from the Genetic material of two females, each parent contributing genetically half of their DNA. I don't think any of the above responses replied to that.Naraht (talk) 14:24, 24 February 2023 (UTC)

I think my last one did.  --Lambiam 18:34, 24 February 2023 (UTC)

So I asked chatGPT "If the Great Basin were filled to overflowing, how deep would it be?"

as well as "where would the deepest point be?", and "where would it overflow?".

Hi!

of course all I got was very well structured and rapid (robot) hand waving, and "it depends", but,

What are the answers?

Thanks Saintrain (talk) 20:53, 22 February 2023 (UTC)

Given a good contour map, the point of overflow should not be hard to determine; it will correspond to a saddle point, where closed contours become open. Local minima should be inside small closed contours; if there are many it will take some effort to spot the lowest. Unfortunately, I did not find a usable contour map online. This one comes close, but is cut off at the edges before we can see the saddle point.  --Lambiam 22:25, 22 February 2023 (UTC)

This is wrong. That park isn't close to all of it. Sagittarian Milky Way (talk) 22:38, 22 February 2023 (UTC)

Specifically, the Great Basin is vastly larger than Great Basin National Park. Cullen328 (talk) 00:20, 23 February 2023 (UTC)

@Lambiam Boy did that get me started! :-)

From: https://water.usgs.gov/GIS/metadata/usgswrd/XML/ha694c_ha1000gb.xml#stdorder

I downloaded: https://water.usgs.gov/GIS/dsdl/ha694c_ha1000gb.zip

which I converted to kml at: https://mygeodata.cloud/converter/shp-to-kml

to open in google earth, where I can draw a path around the perimeter and see the profile.

Fun times, Saintrain (talk) 23:44, 22 February 2023 (UTC)

It's probably near sea level and Mexicali. The bottom is Death Valley. Sagittarian Milky Way (talk) 00:32, 23 February 2023 (UTC)

So, how much sea-level rise would it take to convert Mexicali into North America's future Byzantium? {The poster formerly known as 87.81.230.195} 51.198.55.125 (talk) 08:22, 23 February 2023 (UTC)

Mexicali says it (probably downtown or a median or average) is eight meters above sea level, Great Basin shows a squiggly diagonal line from extreme southeast California to the southernmost part of the basin (in the Baja mountains), if that map is right the lowest point on that squiggly line should be where it'd overflow. Sagittarian Milky Way (talk) 17:01, 23 February 2023 (UTC)

The endorheic watershed is much larger than the lake you'd get if you filled it until overflow, because it also contains areas above the saddle point where the overflow would happen. So if you filled the Great Basin with water, you'd get multiple lakes, each overflowing via one saddle point into a river, connecting it to the next lake or eventually the sea or another watershed. For each of these lakes, one could find the deepest point and the overflow point. Just download the elevation data (see for example ASTER data) and write some code to find the contours. PiusImpavidus (talk) 10:07, 23 February 2023 (UTC)

Indeed it'd be low thousands of feet deep at the lowest part of Death Valley (282 feet below sea level) but only low hundreds of feet deep at the lowest part of the Salton Sink which reaches ~mid-200s feet below sea level. The Greatest Possible Salt Lake rim would be higher than the 4,236 ft altitude Bonneville Salt Flats bed, it couldn't possibly be the same lake as the Salton Sink. Sagittarian Milky Way (talk) 15:24, 23 February 2023 (UTC)

February 23

When did the Jurassic end??

Old sources generally say 130 MYA; newer sources often say 144-146 MYA. Why?? Georgia guy (talk) 14:27, 23 February 2023 (UTC)

Great question! New data occasionally requires re-evaluation of old conclusions. In the case of things like the timing of the Jurassic, it's worth remembering that these aren't arbitrary dates. The Jurassic period is a geologic period, so it is based upon some big change we observe in stratigraphy in rock layers. Those differences are indicative of major events that occurred at that timing. If the timing of these periods changes, it is because we have new data that changes our estimate age for whatever we use to mark between the Jurassic and Cretaceous. Looking that the Jurassic article, it also looks like there is some disagreement about exactly what we want to use as a stratigraphic marker for the end of the Jurassic and the start of the Cretaceous. I wouldn't be surprised to see more changes in the designated timeline as scientists work to figure out and agree upon a specific stratigraphic marker, and then work to most accurately date that marker. --OuroborosCobra (talk) 15:44, 23 February 2023 (UTC)

Read the last paragraph in Jurassic#Upper Jurassic. Ruslik_Zero 11:39, 24 February 2023 (UTC)

Stratigraphy has a number of branches and each of these helps define the boundaries between different chunks of geological time. There's lithostratigraphy, which deals with the types of rocks, biostratigraphy, which deals with the fossilised remains of animals, chemostratigraphy, which deals with variations in chemical composition, magnetostratigraphy, which looks at changes in the polarity of Earth's magnetic field, and finally, chronostratigraphy, which attempts to provide absolute dates for the layers in a sequence. Changes in the dates may arise from new understanding of the sequence around the boundary, based on one or more of these approaches, or new radiometric dates, which can sometimes lead to fairly major changes in the numbers. Mikenorton (talk) 12:56, 24 February 2023 (UTC)

Chemistry of detectable odors and smells

Do all substances whose odour or smell is detectable by humans (both those pleasant and unpleasant), have anything common in their chemical structure? That is, what chemical structure produces a detectable scent? 212.180.235.46 (talk) 16:35, 23 February 2023 (UTC)

This isn't a question that is simple to answer. Lot's of chemical structures produce scents, and there are tons of different scents. In simple terms, yes, all substances with detectable odors, pleasant or otherwise, have their odors due to their chemical structures. As to what structures give what scents, you'll need to pick out some specific scents. --OuroborosCobra (talk) 17:11, 23 February 2023 (UTC)

Quite a few possess an aromatic ring, and then there are the acrid ones like ammonia. It says here that chemical with odors are usually under 300 daltons. Abductive (reasoning) 17:56, 23 February 2023 (UTC)

Yep, the general rule on mass difference is a property of the fact that, to have odor, a compound needs to be able to easily enter the vapor phase at conditions we are trying to smell things (so generally room temperature, 1 atm, pressure, etc). Compounds that are too massive, such as over 300 daltons, generally have intermolecular forces strong enough to prevent much of a sample from entering the vapor phase under those conditions. Basically all compounds that massive will have strong London dispersion force by virtue of physical size and numbers of electrons. Additionally, they may have other forces, such as multiple points for hydrogen bonding. That said, it isn't the mass itself that prevents it from having odor, just that it isn't readily vaporizing due to strong intermolecular forces, and so doesn't reach the nose in the first place. However, you can have small molecules that also lack an odor due to their structures. Methane and ethane have no odor, but methanethiol, which is similar in size, has a very strong odor of rotten eggs, while methanol has an alcohol like odor. Formic acid has a strong odor similar to vinegar. I chose these examples since they are all methane derivatives, but have structural differences that give them their distinctive odors. However, we can also use this to illustrate why the original question is difficult to answer. The -OH (alcohol) group in methanol gave it an alcohol smell, and the -COOH (carboxylic acid) in the formic acid gave it a vinegar odor, but other compounds with those same structural features have very different odors. Menthol has an alcohol group, but smells like mint, not alcohol. Hydrocinnamic acid, on the other hand, has a carboxylic acid group, but smells like cinnamon, not vinegar. This isn't to say that we can't predict odors based on looking at structures, we absolutely can, but it isn't a simple process or easily answered here on the reference desk. --OuroborosCobra (talk) 19:07, 23 February 2023 (UTC)

IP editor: You might be interested to take a look at this website (the good scents company) which has an extensive listing of odor/flavor molecules and their categorisation. Mike Turnbull (talk) 22:21, 24 February 2023 (UTC)

The short answer is that smelly chemicals have no general structural commonality. The structures of hydrogen sulfide (H₂) and sotolon, each having a characteristic smell, are completely different.  --Lambiam 08:02, 25 February 2023 (UTC)

Are molecules with nothing but carbon-12 atoms over or under 12 daltons per atom?

From the mass-energy equivalence of the carbon-carbon bonds. Sagittarian Milky Way (talk) 19:12, 23 February 2023 (UTC)

A dalton is the mass of an unbound neutral carbon-12 atom. Your molecule with only carbon-12 atoms (like graphite or diamond) is bound, so it has a negative binding energy, so it must be slightly lighter. A back-of-the-envelope calculation shows that it will be on the order a hundred-millionth of a dalton less. PiusImpavidus (talk) 19:59, 23 February 2023 (UTC)

So just like nuclear fusion then (hydrogen-1 1.007X, carbon-12 12). I wasn't sure. Sagittarian Milky Way (talk) 20:36, 23 February 2023 (UTC)

Chemical bonds release energy when they form; thus bonded atoms are always lighter than the two atoms are separate. No exceptions. Energy is mass, so the energy released in forming a bond from isolated atoms will always result in a loss of mass. Perhaps immeasurably smaller, but it will be smaller. --Jayron32 22:11, 23 February 2023 (UTC)

That makes sense, you'd have to give an equal amount of energy back to break the bond. Sagittarian Milky Way (talk) 23:26, 23 February 2023 (UTC)

Mold toxicity

Reddit news linked[5] to an article in German saying mold toxins had been found in a certain brand of ketchup. How much should people care about that kind of thing? I figure that mold grows on every kind of food given a chance, and that has been true forever, so any organism alive today must have evolved to deal with a bit of mold in its diet. I won't eat moldy food on purpose but I'm sure I've eaten spots of it here and there by accident.

Should I worry and/or be more careful? Am I in trouble? Is it even surprising that there was some in that ketchup? Question is about mold in general, not particularly about any specific brand of ketchup, though that is where it came up. I had figured mold was like any other microbe, where we encounter zillions of them every day, a few of them are pathogens, and we only get sick from large exposures or especially virulent ones. Maybe I'm naive. Thanks. 2601:648:8200:990:0:0:0:BDFA (talk) 21:57, 23 February 2023 (UTC)

The link is dead, but if it's alternariol its no biggie. Aflatoxins, on the other hand, are worrisome. Abductive (reasoning) 02:03, 24 February 2023 (UTC)

It was indeed alternariol, at 47 μg per kg, above the EU guideline value of 10 μg per kg.^[6]  --Lambiam 09:29, 24 February 2023 (UTC)

I got sick from sealing a dampened bread slice in a ziplock bag then forgetting about it. Instead of coming back in a few days with a magnifying glass and every day after till it was visible if it wasn't then throwing it out it rotted and rotted and rotted till I was a lean, mean nose-leaking machine. When I finally saw it hiding on my high bedroom closet shelf I threw it out and stopped being sick. Are kids' immune systems more sensitive to mold or was it just the fucking large quantity of mold? (it was starting to eat parts of the shelf, nothing an alcoholized paper towel couldn't kill). Sagittarian Milky Way (talk) 03:20, 24 February 2023 (UTC)

February 24

forests of north midwest of United States, insect infestations

Will frequent very cold polar vortices in the midwest help control the tree deaths from insects? Some insects are migrating north due to global warming, will the sudden cold of a polar vortex push them back? thanks, Rich (talk) 21:55, 24 February 2023 (UTC)

Let's take, for example, the Mountain pine beetle which is killing trees in the northwest US and Canada. It is native to North America, and is quite successful in areas like Idaho which get hard frosts. Or the European spruce bark beetle, which appears to have spread from the Iberian Peninsula to kill trees as far north as Norway. Its article says, "... long-distance movements originating from the Iberian Peninsula may have contributed to their invasion of northern Norway spruce forests. Movements like this can happen when various environmental factors such as severe storms, drought, or mass fungal infections damage or kill host trees." Other factors such as poor tree health are driving opportunistic beetle outbreaks. Abductive (reasoning) 17:25, 25 February 2023 (UTC)

February 25

Kids without male sperm

Few years ago, I read report that "Men lose fatherhood monopoly" some female scientist has found that mice sperm can be used to make human female pregnant. https://www.dailymail.co.uk/news/article-79711/We-create-babies-men-claim-scientists.html

Now all these reports are coming.

https://www.theguardian.com/science/2018/oct/14/scientists-create-sperm-eggs-using-skin-cells-fertility-ethical-questions

https://www.earth.com/news/pregnancy-without-men-mice/

https://edition.cnn.com/2022/09/05/world/synthetic-embryos-stem-cells-scn/index.html

I want to know, is it possible that in future a woman can become pregnant, have healthy babies, without any contribution from men? Means no sperm donor, IVF also. Totally zero contribution from male. A child whose biological father is not human male? Liontess79989 (talk) 04:44, 25 February 2023 (UTC)

It is thought to be technically possible through cloning. See also #How close to men being irrelevant? above.  --Lambiam 07:52, 25 February 2023 (UTC)

Ha ha, I can see why the Daily Mail is deprecated, but actually I think they are more reliable than Fox News. Duplicating the chromosomes like that would leave progeny that are very liable to die of any number of mutations. Having two chromosomes compensates for a lot of mutations by having a better copy on the other chromosome. I can't think of any good reason to try it out with human egg cells and I'm pretty certain therefore any ethics committee would nix any such experiment. The Daily Mail is always good at wheeling out all the experts and producing a sensation though! :-) NadVolum (talk) 16:25, 25 February 2023 (UTC)

Storm colors

Why storm colors were changed this morning again? The previous colors were very well-known. I thought that these were standardized. --40bus (talk) 13:07, 25 February 2023 (UTC)

Hey there, 40bus! See Wikipedia:WikiProject Weather/Color RfC. Tails Wx 13:42, 25 February 2023 (UTC)

It would be much better I think to have an option to say what kind of problem one has seeing just like one can set the font size. Then CSS or JavaSCript could automatically adjust the colours appropriately on pictures marked as supporting that, or mybe even patterns for some formats. Fine having colours that work sort of without adjustment but far better to just use colours that are chosen to be adjusted. NadVolum (talk) 17:59, 25 February 2023 (UTC)

Aren't there skins in our preferences for that? Abductive (reasoning) 19:26, 25 February 2023 (UTC)

February 26

Theta Muscae

I recently removed information about an optical companion of this star because the source used failed verification — in particular, it did not mention Theta Muscae at all. Any information you can find about this "Theta Muscae B" object? –LaundryPizza03 (dc̄) 01:17, 26 February 2023 (UTC)

The cited source mentions a system HD 204 827 AaAb, writing: "This object was not present in version 1 of GOSC. Mason et al. (1998) give a separation of 0″.12 and a Δm = 1.2 for the Aa + Ab system. B is more than 3 mag fainter. In Maíz Apellániz et al. (2004), a classification of B0.2 V was given." Could HD 204 827 refer to θ Muscae?  --Lambiam 03:10, 26 February 2023 (UTC)

Answering myself: apparently not.^[7]  --Lambiam 03:14, 26 February 2023 (UTC)

I knew that. Theta Muscae is HD 113904. –LaundryPizza03 (dc̄) 04:07, 26 February 2023 (UTC)

Algorithm for simulating cling and skid in billiards

So I asked a conversational search engine (as outlined on a talk page discussion regarding use of AIs) to find the algorithm for simulating cling/skid/kick in game of pool, unfortunately, it turns out that it produces good sounding but irrelevant results and even after editing, no luck for that.

However, there is a paper for different elasticity on different surfaces, which makes me curious; can Bounce Maps be changed dynamically (striking a cue ball or even a ball-to-ball collision changes the physical properties on that particular surface), and what about changing friction (which I know is responsible of throws) instead of elasticity for different surface? 2001:448A:3046:59C8:9074:C5DB:F266:4DEE (talk) 03:12, 26 February 2023 (UTC)

Soviet nukes

I think I had already asked this question some time ago, but never got an answer: at what point did Soviet nuclear weapons start being designed to be single-point safe? And in particular, was the R-13 (missile) (as deployed, for example, on the K-19 submarine) single-point safe? How about the 9M/9N-series tactical nuclear missiles (presumably the kind of warhead which was being illegally transported in the film Atomic Train, where it was incorrectly referred to as a 667-series warhead)? 2601:646:9882:46E0:99E1:8CB:A1C6:C5E (talk) 04:37, 26 February 2023 (UTC)