Wikipedia:Reference desk/Archives/Science/2021 September 12

= September 12 =

heart condition from joke
There is a corny joke/prank that kids play on each other. You shake the other person's hand, but while doing so, you give it a series of pulsating squeezes, like a heartbeat, and say "Hi, I'm from the heart association". (I told you that the joke was corny).

I learned this joke in school and tried it on my dad, who got a chuckle out of it. It turns out he had a professional acquaintance who was a heart surgeon, so when the opportunity next came up, he tried the joke on the surgeon. The surgeon, without missing a (no pun intended) beat, said something like "you've got aortic deficiency" or some other such medical condition. One got the impression that the surgeon had been through this many times before, and had the answer worked out ahead of time.

I had remembered "aortic deficiency" but WP doesn't have an article about that, so maybe I have it wrong. Is there another condition that sounds like that, which would fit the situation? 2602:24A:DE47:B8E0:1B43:29FD:A863:33CA (talk) 01:32, 12 September 2021 (UTC)
 * Aortic insufficiency. Abductive  (reasoning) 04:12, 12 September 2021 (UTC)
 * Thanks, that must be it, though the symptoms in the article don't match the joke afaict. Close enough though. 2602:24A:DE47:B8E0:1B43:29FD:A863:33CA (talk) 03:38, 13 September 2021 (UTC)
 * An on-the-spot diagnosis matching the setting is cardiac arrhythmia. This is an umbrella designation for many more specific diagnoses, such as atrial tachycardia. Nothing with "aortic" or "-ficiency" in the lot, though. --Lambiam 07:34, 13 September 2021 (UTC)

If acid/bases are opposites then why they react on human skin equally?
Endothermic and exothermic are treated opposite based on their hot and cold reactions but in case of acids/bases, they are treated as opposites in ph scale, but they react on human skin equally, why so? Rizosome (talk) 01:43, 12 September 2021 (UTC)
 * Each acid and base reacts differently to human skin. Some chemicals can cause what we call "chemical burns," and these injuries are in no way equal. An important feature of reality is that human language is inadequate in describing reality. 2600:1702:2670:B530:45D:3246:2D5F:FEC0 (talk) 02:46, 12 September 2021 (UTC)
 * True. The OP needs to keep in mind that the terms "acid" and "base" are general chemical classifications. The corrosive aspects of individual examples vary. One item is Citric acid, which is mild enough to be used in food, even though in its pure form it can be troublesome. ←Baseball Bugs What's up, Doc? carrots→ 03:42, 12 September 2021 (UTC)
 * The broad effects of acids and bases on skin are also different. --Wikimedes (talk) 05:39, 12 September 2021 (UTC)
 * You probably meant or are talking about concentration. 67.165.185.178 (talk) 06:54, 12 September 2021 (UTC).
 * Concentration is distinct from Acid strength. If I remember my GCSE chemistry correctly, there are things that a strong acid can do that a weak acid simply cannot, no matter how concentrated that weak acid is. Iapetus (talk) 09:14, 13 September 2021 (UTC)
 * Well human skin is neither an acid or a base, or water, so you wouldn't expect acids and bases to react with human skin much differently. 67.165.185.178 (talk) 06:54, 12 September 2021 (UTC).


 * See homeostasis. Excessive heat, insufficient heat, excessive pH, insufficient pH, excessive pressure, insufficient pressure, etc. will all damage skin. The differences between the types of damage may not be very obvious in some cases. So, for instance, "chemical burn" describes a lot of different types of skin damage. Chemicals have traits other than "will they hurt my skin?" (water and olive oil are both harmless, but anyone attempting to drink them will soon notice a difference). Distinguishing between chemicals, using measurements like pH, is useful, even if they have similar effects on skin. The treatment for acid burns generally depends on the substance causing the burn, though obviously removing the irritant is usually part of the treatment. Some antacids are pH buffers, designed make the pH of any solution they are added to change to a target pH (or close). I've answered several questions here because I'm not sure which one you are asking, Rizosome; please feel free to clarify. HLHJ (talk) 21:04, 12 September 2021 (UTC)
 * As sometimes happens, the OP started with a false premise, and it went downhill from there. :( ←Baseball Bugs What's up, Doc? carrots→ 21:59, 12 September 2021 (UTC)

Should we generalize Coca trees, Cola trees, Cocoa trees, Coffea trees and Camelia Sinesis are all related?
Is it true to generalize that Coca trees, Cola trees, Cocoa trees, Coffea trees and Camelia Sinesis are all related?

If so, in what context could they be related?


 * Significant evolutionary proximity
 * Caffeine biosynthesis? (or other chemically similar stimulants biosynthesis?)

Thanks, 182.232.55.189 (talk) 08:36, 12 September 2021 (UTC)


 * Coca plants are in the genus Erythroxylum in the family Erythroxylaceae. Plants in the Cola genus are in the family Malvaceae, subfamily Sterculioideae. Also in the Malvaceae is Theobroma cacao, the 'cocoa tree'. Coffea is in the family Rubiaceae. Camellia sinensis is in the family Theaceae. So only cola and cocoa plants are in the same botanical family. PaleCloudedWhite (talk) 13:03, 12 September 2021 (UTC)


 * Glancing at the relevant articles, they are all eudicots. —Tamfang (talk) 01:41, 14 September 2021 (UTC)
 * Considering that the eudicots comprise about 75% of all flowering plants (about 175,000 species), that isn't narrowing down relatedness very much. PaleCloudedWhite (talk) 06:56, 14 September 2021 (UTC)

The thermometer in Leslie cubes
I recently learnt what a Leslie cube is and I wonder what John Leslie (physicist) used to compare the radiation. From reading Wikipedia, I understand it was some kind of differencial thermometer (no article?) or a pyrometer. But I don't know what Leslie had available in his time. He invented the aethrioscope, which our articles says "may be used as a pyrometer too.". So what did he use? Do we have an article about it? --Error (talk) 21:29, 12 September 2021 (UTC)
 * 1911 Encyclopædia Britannica/Leslie, Sir John says:
 * Leslie’s main contributions to physics were made by the help of the “differential thermometer,” an instrument whose invention was contested with him by Count Rumford. By adapting to this instrument various ingenious devices he was enabled to employ it in a great variety of investigations,
 * --Error (talk) 21:49, 12 September 2021 (UTC)


 * We have an article on the Beckmann thermometer, which is a differential thermometer. Apparently, Mortimer Granville also invented one. --Lambiam 07:23, 13 September 2021 (UTC)


 * I have created a provisonal redirect for Differential thermometer.--Shantavira|feed me 08:24, 13 September 2021 (UTC)