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February 5

how hard is it raining?

It's obvious from the sound that it's raining fairly hard outside here right now. How hard? Well in principle I could set a rain gauge outside and let it collect for an hour and look at the water level, but 1) that takes a while, and 2) the rain intensity fluctuates and I'm interested in the instantaneous level.

Is there a known simple way to do this, and are there relevant measurement units other than mm/hour or whatever? Audio, speed of windshield wiper motion required to keep the windshield transparent, etc. are all indicators or rain intensity but for whatever reason, I never see the topic come up. 2601:644:8581:75B0:0:0:0:512B (talk) 00:14, 5 February 2025 (UTC)[reply]

Perhaps, because rain intensity is so variable in both duration (it can change over a few seconds) and locality (a few tens of yards), the difficulty of doing so meaningfully has been too much of a disinsentive to developing a standardised and widely used method.

Note however that the article section linked above references two independent ways of expressing the property. {The poster formerly known as 87.81.230.195} 94.7.205.116 (talk) 04:01, 5 February 2025 (UTC)[reply]

The size of a raindrop can vary considerably, typically ranging from 0.5 mm to 4 mm. Rain precipitating at a given rate (volume of water per unit of time) will appear more intense when the raindrops are large. Large drops fall with a higher speed^[1] and impact with more energy for the same amount of precipitation, possibly by several orders of magnitude. ‑‑Lambiam 06:18, 5 February 2025 (UTC)[reply]

You could use the intensity of reflected radar signals from a Weather radar. Iapetus (talk) 11:53, 5 February 2025 (UTC)[reply]

Depending on what you mean by hard, wind will be a confounding factor. What I mean is, if you're listening to the sound of the rain and supposing it to be raining fairly hard, the wind speed is going to influence that experience. Matt Deres (talk) 14:56, 5 February 2025 (UTC)[reply]

I'm a big fan of having something separate that just listens or looks. I can see problems with applying that to rain though. Perhaps you could stand to just measure it and record the sound on a number of different occasions and then train an AI? NadVolum (talk) 20:18, 5 February 2025 (UTC)[reply]

There are automatic digital urine flowmeters that deliver a printout of Urine flow rate to a urologist that can also be used as a recording raingauge. Philvoids (talk) 10:18, 9 February 2025 (UTC)[reply]

Hence you would know when it is pissing it down. Mike Turnbull (talk) 13:34, 9 February 2025 (UTC)[reply]

February 6

Coat Moth (England)

What species is the Coat Moth, found in Warwickshire, England, and referred to in this 1917 article? We have no entry under that name, nor does Wikidata, and Wikispecies has nothing relevant. Most Google Searches find the unrelated Joseph's Coat Moth, of Australia. Andy Mabbett (Pigsonthewing); Talk to Andy; Andy's edits 12:14, 6 February 2025 (UTC)[reply]

Looking in Newspapers.com (pay site) for "coat moth" in British newspapers, I'm not finding anything under that exact name, but one thing that turned up is "goat moth". Might that be it? ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:35, 6 February 2025 (UTC)[reply]

A scan of the original article is at the bottom of the page, and it clearly shows "goat moth" - coat moth is a typo by the transcriber. The goat moth also matches in that it was indeed eaten by Romans. Smurrayinchester 15:08, 6 February 2025 (UTC)[reply]

Looks looks Pliny was looking in oak trees. So his flour-fattened grub was more likely the larvae of the Cerambyx cerdo. Sound equally disgusting. Martinevans123 (talk) 15:15, 6 February 2025 (UTC)[reply]

It doesn't seem to match the description, but my first thought was that it was another name for clothes moth, given that coats are a frequent target. Matt Deres (talk) 13:53, 6 February 2025 (UTC)[reply]

I'm pretty sure moths prefer coats to goats (although I've never tried keeping goats in my wardrobes). But yes, it might well be Joseph and the Amazing Technicolor Dream Moth, i.e. the Joseph's Coat Moth. Sorry, fake moth news, it seems. Martinevans123 (talk) 14:30, 6 February 2025 (UTC)[reply]

"Coat moth" is a scanno for "goat moth", whose caterpillars indeed, as stated in the article, bore into tree trunks and branches. 50.196.138.188 (talk) 15:25, 6 February 2025 (UTC)[reply]

This section is resolved and can be archived. If you disagree, replace this template with your comment. Thanks all; scanno it is. Andy Mabbett (Pigsonthewing); Talk to Andy; Andy's edits 16:26, 6 February 2025 (UTC)[reply]

My question regards scatter plot in the statstical field of PCA

The following questions are aimed to experts in this field of statistics. It's about describing population genetics & migrations. E.g., see this article

What are the units of the values in fig1(A) in the article, and what's the meaning of these values ?
What's the meaning of (-) values here ? & why the order of values is opposite in both axes, namely, from (-) to (+) values, or the other way around ?
In fig1(B) the pictures of different ancient genomes are shown, from a variety of sites. What's the meaning of the different colors displayed (orange, green etc) ? how the proportions between them were determined ? בנצי (talk) 21:19, 6 February 2025 (UTC)[reply]

1. kaBCE is "kilo-annum Before Common Era", so something marked 1 kaBCE took place in 1,000 BCE. The chart is showing the estimated age and location of the individuals analyzed in the paper.

2. I don't see the - values you are referring to.

3. The colors are just to differentiate the different data points.

PianoDan (talk) 22:49, 6 February 2025 (UTC)[reply]

All the above questions referred to fig2 and not to fig1. Sorry. Hence, the 1st 2 answers are irrelevant.

What do you mean by your 3rd answer ? unclear.

Thanks for the attention, בנצי (talk) 09:13, 7 February 2025 (UTC)[reply]

What is unclear? Is it the word "colors"? Is it the word "differentiate"? Is the word "different"? Is it the term "data points"? The sentence is extremely clear to me. The data points are given different colors so you can tell one from another easily. Just as the answers are given different numbers so you can tell them from one another easily. 68.187.174.155 (talk) 12:44, 7 February 2025 (UTC)[reply]

The image is so fuzzy that I cannot decipher the axis labels with certainty; my best guess is that the x-axis, with ticks at 0.05, 0.00, −0.05 and -0.10, is labelled "PC1 (0.45%)" and that the y-axis, with ticks at −0.15, -0.10, -0.05, 0.00, 0.05 and 0.10, is labelled "PC2 (0.34%)". There is no doubt in my mind that "PC" is an abbreviation of principal component and that PC1 and PC2 represent the two components resulting from a principal component analysis that together carry the largest variance, about 0.79% if my guesses are correct.

The colours of the circles are explained inside the frame of the plot: light green for the genomes of ASH_LBA individuals, amber for ASH_IA1 and blue for ASH_IA2. The grey circles are for the genome sample taken from present-day west Eurasians. ‑‑Lambiam 19:00, 7 February 2025 (UTC)[reply]

February 8

Clostridium tetani

Per Clostridium tetani, it's an obligate anaerobe presumably killed by normal concentrations of oxygen. So how does it survive and reproduce in soil and in human blood full of oxygen? Even if it's spores are extremely hardy, they would still grow into bacteria which, as I understand, theoretically should die quickly. Brandmeister^talk 08:48, 8 February 2025 (UTC)[reply]

The oxygen in blood is stored in red blood cells, not free and so not a danger to bacteria. As for soil I don't know the exact chemistry of it but I would think oxygen is depleted by organisms that use it like we do, and not replenished by photosynthesis which doesn't take place underground. --2A04:4A43:909F:F990:D0:B7A6:F407:709A (talk) 09:14, 8 February 2025 (UTC)[reply]

Various anaerobic bacteria live in soil. Other common examples are those that cause Digital dermatitis and Foot rot in cattle. {The poster formerly known as 87.81.230.195} 94.8.123.129 (talk) 10:55, 8 February 2025 (UTC)[reply]

Also Clostridium botulinum, producing the neurotoxin causing botulism. ‑‑Lambiam 20:24, 8 February 2025 (UTC)[reply]

Bacterial spores only germinate when environmental conditions of viability of the reactivated cell are met, which for the genus Clostridium (and obligate anaerobic bacteria in general) means the environment needs to have a very low concentration of free oxygen. Otherwise the spores can remain dormant for an indefinitely long period. ‑‑Lambiam 20:40, 8 February 2025 (UTC)[reply]

And tetanus in fact "prefers" hypoxic areas in the body—hence the textbook case of infection resulting from a nail puncture, contaminated needle, bite wound, or other sharp object trauma, which introduces the spores into a deep wound where they're able to germinate. Tetanus spores ingested (such as by grazing herbivores) or that contact surface wounds rarely cause infection, because of the ambient oxygen plus outcompetition by existing skin/gut flora.

While C. tetani is frequently benign in the soil or in the intestinal tracts of animals, it can sometimes cause the severe disease tetanus. Disease generally begins with spores entering the body through a wound.[5] In deep wounds, such as those from a puncture or contaminated needle injection the combination of tissue death and limited exposure to surface air can result in a very low-oxygen environment, allowing C. tetani spores to germinate and grow.[2] As C. tetani grows at the wound site, it releases the toxins tetanolysin and tetanospasmin as cells lyse.[1]

To my understanding tetanus doesn't frequently cause bacteremia; the symptoms of infection result from the toxins it secretes which then diffuse into the blood and lymph which spreads them in the body.

There's a well-known phenomenon with some parallels, the Warburg effect, where cancerous tumors generally show preference for anaerobic metabolism and wind up promoting a hypoxic tumor microenvironment around the tumor. Among other things this "frees them" from the need to ensure and maintain a robust blood supply to the tumor to keep the oxygen coming—which impedes the body's immune system from detecting and getting at them, because the blood is what white blood cells travel around in. And the hypoxic environment also hinders those same WBCs, because WBCs need oxygen! --Slowking Man (talk) 20:58, 8 February 2025 (UTC)[reply]

"Mono-" chemical compounds

From chemical nomenclature:

The prefix mono- is never used with the first element.

This sentence immediately made me think of monosodium glutamate. Is the "never used" sentence wrong, or is there some reason that MSG doesn't disprove the rule? Nyttend (talk) 11:56, 8 February 2025 (UTC)[reply]

That part of IUPAC nomenclature applies to covalent-bonded binary compounds A-B. So iodine monochloride not "monoiodine chloride" or "iodine chloride". MSG is an ionically-bonded salt, where the glutamic acid could in principle take one or two sodium counterions but in MSG only has one. Mike Turnbull (talk) 12:23, 8 February 2025 (UTC)[reply]

The MSG article shows that the IUPAC name for the substance is "Sodium 2-aminopentanedioate". As it was originally named and patented back in 1908 by Ikeda, long before nomenclature rules, I assume that hardly anyone uses the IUPAC name. Mikenorton (talk) 12:24, 8 February 2025 (UTC)[reply]

... actually, sodium (2S)-2-ammoniopentanedioate if you want to name the naturally-chiral version systematically, rather than trivially. IUPAC naming is a nightmare. Mike Turnbull (talk) 12:38, 8 February 2025 (UTC)[reply]

Hi, thank you; I know the difference between ionic and covalent, but I'd completely forgotten that I was reading a section about covalent only! Sorry for the absentmindedness that looked like cluelessness. Nyttend (talk) 19:43, 8 February 2025 (UTC)[reply]

Now, we learn in school that no prefix attached to the first element is preferred over mono-. But look at iodine pentoxide. Georgia guy (talk) 15:54, 8 February 2025 (UTC)[reply]

February 9

Word for fruit defect？

is there a professional jargon for this kind of marks on an orange? The dent is not at the top or bottom that each orange has, but in the middle of the fruit. It's not deep enough to reach the pulp. Trade (talk) 04:23, 9 February 2025 (UTC)[reply]

This Orange Defects and Blemishes Glossary calls it "scarring". (At least, I think this is what we see; the sections "Symptoms and Signs" in this glosssary are not informative.) ‑‑Lambiam 08:07, 9 February 2025 (UTC)[reply]

February 12

Integrating sphere?

Am I correct in my assumption that this (pictured) is an Integrating sphere? The LoC is rather ambiguous with its description. Jay Cubby 04:46, 12 February 2025 (UTC)[reply]

Based on the shape and the uniform white interior coating, your assumption appears to be a safe one. It seems that the arm holding the bulb can swivel so as to position the bulb in the centre. The National Bureau of Standards was definitely familiar with the technology: "In 1915 a large integrating sphere of 2.2-meter (88-inch) diameter was constructed at NBS by Rosa and Taylor".^[2] The sphere in the photo, taken in 1938, appears considerably smaller and thereby more convenient for routine testing. A decade later the NBS would install a 15-foot (4.6-metre) integrating sphere.^[3] ‑‑Lambiam 10:30, 12 February 2025 (UTC)[reply]

@JayCubby: That was a very long and cryptic question title. I took the liberty of replacing the File statement which formed the heading with a short question, and moving the statement into your question's body. Feel free to change or revert.

Microplastics detectors in humans

Amid recent publications about microplastic particles in humans, I wonder is there some medical imaging device capable of visualizing the volume of microplastics inside a human (similar to MRT scan, possibly based on density difference between microplastics and human blood and tissues)? 212.180.235.46 (talk) 08:50, 12 February 2025 (UTC)[reply]

Given the huge variety of plastics around I think that is very unlikely. Shantavira|^{feed me} 09:46, 12 February 2025 (UTC)[reply]

Medical MRI detects differences in hydrogen density, which is high in blood and cytoplasm due to the high H₂O (water) content. Major contributors to microplastics^[4] are PP (0.855–0.946 g/cm3), EVA (0.921–0.970 g/cm³) and PET (1.370 –1.455 g/cm3), all of which have known, hydrogen-rich chemical compositions. Ranges for the mass densities of human blood and tissues are known, as well as for these plastics. If the chemical make-up of various human tissues is known – more specifically, the contribution of H⁺ to their mass – it should be possible to calculate ranges for their respective hydrogen densities and see if those of the plastics overlap with human blood and tissues. ‑‑Lambiam 12:19, 12 February 2025 (UTC)[reply]

Assuming you are interested in detecting microplastic particles in live humans and not samples from deceased humans, MircroRaman, Flow Cytometry, and Spectoscopy have been reported as capable of detecting plastics in various substances excreted from the body as well as some samples taken from the body. 68.187.174.155 (talk) 17:18, 12 February 2025 (UTC)[reply]

February 13

Exoplanet naming convention

I've seen a lot of exoplanet names and I haven't noticed much consistency in the separation of the parent star's designation from the letter representing the exoplanet with a space: e.g., WASP-7b vs. WASP-7 b. I've noticed that Wikipedia appears to do this rather randomly (see the entries in this category, for example). NASA's Exoplanet Catalog consistently leaves a space between the star's designation and the exoplanet's letter. See also Caltech's NASA Exoplanet Archive. A page at the International Astronomical Union's website explaining exoplanet naming conventions doesn't specifically discuss the spacing issue, although it does seem to use them randomly (e.g., "CoRoT-7b" and "GJ 1214 b"). I'm wondering if there's some kind of standard for the spacing issue. Perhaps certain catalogs consistently use spaces while others consistently don't? Nythar (💬-🍀) 05:22, 13 February 2025 (UTC)[reply]

The section "Scientific Designations" on the IAU's website uses "Kepler-186f", "CoRoT-7b", "Qatar-1b" and "Kepler-34(AB)b", but all 164 names in the section "List of Exoplanet Names" have a space before the planet letter, such as "HAT-P-12 b" and "WASP-17 b". Obviously, when the parent star's designation ends on a letter, there has to be a space; we don't want to send a generation ship to Proxima Centaurib or they might get lost when the Nth generation cannot find Proxima Centaurib in the ship's star catalogue. For this reason alone, the obvious and easy consistent rule is to always use a space. Furthermore, for the non-cognoscenti "WASP-7b" might create the impression that this designates item 7b in a catalogue of the findings of the WASP project. That said, the discoverers of this exoplanet themselves wrote "WASP-7b" without a space in the report on their find.^[5] ‑‑Lambiam 11:31, 13 February 2025 (UTC)[reply]

Speaking as an amateur, and one-time aspiring professional, astronomer, I think what is going on is that the relevant catalogues, scientific papers and journal articles are generally compiled and written by astronomers for astronomers, who in context all understand exactly what is being discussed and referenced, so there is no compelling need for a universally observed stylistic convention. (Though as a former science book editor, I would have expected an individual journal, say, to have one as part of its House style manual.) Perhaps one day some sub-committee of the IAU will pronounce on the matter. {The poster formerly known as 87.81.230.195} 94.8.123.129 (talk) 07:44, 14 February 2025 (UTC)[reply]

February 14

Ethidene dichloride

Morning Folks!! Would this synthetic gas ethidene dichloride be this gas 1,1-Dichloroethane. There is a link/content there stating it was an inhalational anesthetic and I would assume it was, but I'm no chemist. I did a search and it linked the two. It's for the Joseph Lister article. Thanks. scope_creep^Talk 06:27, 14 February 2025 (UTC)[reply]

Yes, ethidene is an obsolete term for ethylidene, and ethylidene dichloride is the same as 1,1-dichloroethane. ‑‑Lambiam 07:31, 14 February 2025 (UTC)[reply]

Morning @Lambiam: Thats grand. Thank You!! scope_creep^Talk 09:11, 14 February 2025 (UTC)[reply]

While reading on the topic of this substance as an an(a)esthetic, I found dichloromethane was already in use at the time ethidine was being tested (see PMC 2263151). DMacks (talk) 07:02, 16 February 2025 (UTC)[reply]

February 16