Wikipedia:Reference desk/Archives/Science/2023 April 19

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April 19

Conflicting definitions of systolic hypertension and hypotension

Diastolic vs systolic blood pressure chart comparing European Society of Cardiology and European Society of Hypertension classification with reference ranges in children

While drawing this chart, I was unsure how to shade the bottom-right region (systolic > 140, diastolic < 60 mmHg). Systolic hypertension states

“ If the systolic blood pressure is elevated (>140) with a normal (<90) diastolic blood pressure (DBP), it is called isolated systolic hypertension ”

Hypotension states

“ ... diastolic of less than 60 mmHg is generally considered to be hypotension. ”

How should the transition between the regions look like?

Thanks,
cmɢʟee⎆τaʟκ 09:37, 19 April 2023 (UTC)

In this scatter plot there are no points in that area. Same here, here and here. This article uses the description "isolated systolic hypertension in combination with diastolic hypotension", which suggests there is no commonly understood specific term for this rare combination.  --Lambiam 21:32, 19 April 2023 (UTC)

Thanks a lot, @Lambiam. I've extended the hatching in http://commons.wikimedia.org/w/index.php?title=File:Hypertension_chart.svg&diff=prev&oldid=752432326 cmɢʟee⎆τaʟκ 06:27, 20 April 2023 (UTC)

Least Endemic specific area?

Not quite sure the best way to ask the question, but if an asteroid hit/volcanic eruption was to occur in the Galapagos Islands and destroyed everything within 100 km of the hit/eruption, it would completely wipe out a number of species in the wild. I would guess this would be equally true on other isolated islands. My question is the Reverse. Is there any place outside Antarctica where destroying everything within 1000 km of a given point would wipe out *no* species in the wild? My *guesses* would be Siberia (especially on the edge of the Arctic Ocean), the Sahara and Central North America (Centered around the Black Hills of South Dakota?)

Would the same locations be true 10,000 years ago, or (for example) would a hit in Northern Siberia wipe out a species of Mammoth (or one of the large cats that preyed on it).Naraht (talk) 14:55, 19 April 2023 (UTC)

My guess is that the answer is that no land area on earth as large as 3,140,000 km² contains zero species which are only within that 3,140,000 km² area; which is to say that everywhere that large would have some species that exist nowhere else. (that's the area of a circle with radius of 1000 km, FWIW) For example, the Amur lemming has a range smaller than this. If something wiped out everything in that radius, we'd likely lose all Amur lemmings. When you get down to the level of insects and the like, there are MANY such insects which may have tiny ranges; heck 25% of all known species are Beetles alone, many of them with much smaller ranges than you've noted. --Jayron32 15:17, 19 April 2023 (UTC)

User:Naraht is correct; the taiga biome is utterly depauperate and the only endemic "species" in any given area are likely apomictic dandelions. Abductive (reasoning)

Is it possible to be beaten in the dream and due to it wake up in pain?

Maimonides et al, say in their bible interpretation that the story with Jacob in Genesis 32, 25-31 in which Jacob was limping because of his hip due to the touch of the angle, was in his dream as a part of the prophecy. Nachmanades, on the other hand, rejects this opinion because the bible states that Jacob was limping, so it must happen in reality. Maimonides's son, Abraham Maimonides (and others) explains that despite that all this story was in his dream, one can wake up in pain due to fighting or so. As proof, he mentions the wet dream, that one can see a sexual attractiveness that can cause ejaculation. Now my question is: Is Abraham Maimonides opinion supported scientifically or rejected? ThePupil (talk) 19:15, 19 April 2023 (UTC)

Medically unexplained physical symptoms are well documented. It's entirely plausible that a person can feel pain as a symptom for which there is no clear physical antecedent; by definition, a symptom is "a person's reported subjective experiences", experiences of pain are not normally observable by anyone except the person experiencing the pain. --Jayron32 19:28, 19 April 2023 (UTC)

As far as self-observation goes, I am inclined to think that it is the physical need to ejaculate excess seminal fluid (which is continually secreted) that often (though not always) induces a sexual dream, not the other way around. I have on occasion dreamed of urination rather than sexual activity in the circumstance.

On a different note, I have sometimes dreamed of something that affects vision, such as being blinded by a bright light, or reading lines of printing that in real life tends to leave reversed afterimages, and then woken up in near darkness but experiencing those visual effects.

Perhaps Jacob experienced a pain-causing problem with his hip (a camel kicked him while he was asleep maybe?) that caused him to dream of wrestling with an angel, rather than the reverse. {The poster formerly known as 87.81.230.195} 90.213.18.208 (talk) 03:04, 20 April 2023 (UTC)

I concur -- (WP:OR) I've personally had similar experiences (namely, subsequent to some kind of injury which caused me lingering pain, I would sometimes have dreams where I received a similar kind of injury! In particular, I have a vivid memory of one extreme example -- having a mild, non-life-threatening heart arrhythmia, I once dreamed that I was fighting in the White Army during the Russian civil war and that a Red Army soldier bayonetted me to death (which, BTW, also disproves the common myth that it is impossible to have a dream of getting killed and/or that one actually dies if he/she does so), and when I woke up screaming a couple seconds later, I nevertheless had the presence of mind to notice that I was experiencing the symptoms of this arrhythmia!) 2601:646:9882:46E0:21CB:BD15:76E:9EF1 (talk) 06:53, 20 April 2023 (UTC)

ThePupil, you seem to ask a lot of questions around the template of "this excerpt from the Torah/Bible, or from an exegesis thereof, says (X). Is (X) scientifically plausible?"

If those questions are just curiosity-driven, that’s fine, but then the theological source has no bearing and should be omitted from the question. On the other hand, if you are using those questions as a means of proving or disproving certain theological positions, that’s not really a productive pursuit. You might be able to prove that certain religious texts contain some statements incompatible with modern science, sure, but nobody contests that. Or you might be able to prove that certain unclear passages, read in the right way, reveal scientific insight that was not known at the time, but that tells more about the reader than about the text - it is much closer to numerology than to history. Tigraan^{Click here for my talk page ("private" contact)} 13:02, 20 April 2023 (UTC)