Wikipedia:Reference desk/Archives/Science/2017 May 2

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May 2[edit]

Squirrel ID[edit]

Is it your basic Eastern gray squirrel, or something else? I took this photo two weeks ago in downtown Norfolk, in the coastal Hampton Roads area of Virginia. Nyttend (talk) 00:53, 2 May 2017 (UTC)[reply]

The odd thing is that tail looks really small, almost like it was bobbed. Other than that it looks like an ordinary Eastern gray squirrel. Shock Brigade Harvester Boris (talk) 00:58, 2 May 2017 (UTC)[reply]
The tail could, of course, have been lost to a predator, or for that matter, to a car. --76.71.6.254 (talk) 01:00, 2 May 2017 (UTC)[reply]
Already noted; see filename :-) I had thought of calling the file something like "Manx squirrel.jpg". Nyttend (talk) 01:02, 2 May 2017 (UTC)[reply]
Looks to me like the tail could simply be bent around the far side of the tree. 2606:A000:4C0C:E200:3CF4:5668:5FB:EC43 (talk) 01:19, 2 May 2017 (UTC)[reply]
No, it was outright missing; this was easy to see when the squirrel moved as I walked nearby. Nyttend (talk) 01:24, 2 May 2017 (UTC)[reply]
Coincidentally, earlier today I released three Eastern gray squirrel orphans (as a rehabilitator with Wildlife Welfare Inc.) -- and yes, the coloration is within the range for an Eastern gray (e.g.) -2606:A000:4C0C:E200:3CF4:5668:5FB:EC43 (talk) 01:47, 2 May 2017 (UTC) ... See also: Fox squirrel, which your bobtail squirrel is not (note the difference in the underside: yours is white-ish).[reply]
Thank you all for the ID work. Partial colorblindness sometimes makes animal IDs difficult. Nyttend (talk) 02:09, 2 May 2017 (UTC)[reply]
(Your squirrel is more reddish-brown than a typical gray squirrel) 107.15.152.93 (talk) 07:09, 2 May 2017 (UTC)[reply]
Really? Because the coloration almost exactly matches the first image in the article titled eastern gray squirrel. --Jayron32 12:28, 2 May 2017 (UTC)[reply]
Eastern gray squirrels vary a bit on coloration, depending on region/subspecies. Our page lists five subspecies. WP:OR some of them have more red/brown, some have less. Even in one location and within subspecies, if you look closely, you will see variation in coloring.SemanticMantis (talk) 15:37, 2 May 2017 (UTC)[reply]
  • WTF? This looks like an eastern grey squirrel whose tail is not visible. Why is this such a McGuffin?
It's an object pursued by the protagonist of a story for reasons that are never fully explored? ApLundell (talk) 15:02, 2 May 2017 (UTC)[reply]
Yes, see: "Eeyore's Tale of the Missing Tail". 107.15.152.93 (talk) 21:36, 2 May 2017 (UTC) -Thanks for the setup ;)[reply]

The tail's not visible because it's not attached to the squirrel anymore; as I note above, as the squirrel moved around the tree somewhat, and I saw several different perspectives on it, but never could I see an attached tail, even when the animal was running straight away from me. That's the whole reason I took this photo; I don't take (let alone upload) images of ordinary animals, especially ones as common as this species. See the "Discussion" section of Commons:COM:SCOPE — we probably have enough ordinary images of Sciurus carolinensis already, so I don't generally upload my own images of animals, but this is "another educationally distinct image", so I uploaded it even though it's probably not the best quality. Nyttend (talk) 00:27, 3 May 2017 (UTC)[reply]
This squirrel's had a run in with an aged owl tired of it's antics? Or is that only a local tale in the the English Lakes?ShakespeareFan00 (talk) 19:46, 7 May 2017 (UTC)[reply]

What does it mean "cold sweat"?[edit]

What does it mean "cold sweat"? in some of medical conditions for example there is a using of "cold sweat". Does it mean that there is also "hot sweat"? I don't understand the meaning of "cold sweat" and how it can be differentiated by a regular person. 93.126.88.30 (talk) 23:03, 2 May 2017 (UTC)[reply]

You are cold and still sweating. Therefore, your sweat is not part of the standard biological function to cool down. 71.85.51.150 (talk) 00:12, 3 May 2017 (UTC)[reply]
In the vernacular, it means you're scared, circumspect or anxious, e.g: (from "Cold Sweat") Brown's lyrics describe how his woman's affections make him "break out in a cold sweat."107.15.152.93 (talk) 00:52, 3 May 2017 (UTC)[reply]

Our diaphoresis article redirects to perspiration, which is a shame, because diaphoresis is usually defined as excessive or unexpected perspiration given the environmental conditions and the level of exertion. See diaphoresis overview here: [1]. Dr Dima (talk) 00:44, 3 May 2017 (UTC)[reply]

WebMD article on the subject: [2] --107.15.152.93 (talk) 00:57, 3 May 2017 (UTC)[reply]
  • A "cold sweat" is basically a term for the fight-or-flight response triggered by activation of the sympathetic nervous system, usually as a result of stress. One of the effects of sympathetic activation is to increase sweating, independently of body temperature.

Antimicrobial properties of copper[edit]

I was doing some reading about copper: Antimicrobial properties of copper and Copper_in_heat_exchangers#Biofouling_resistance and was wondering whether the copper slowly dissolves in these applications or not. As in, is the antimicrobial properties due to dissolved copper ions in the water? Or is copper completely insoluble in water, not even in minute amounts, and that antimicrobial properties only works at the water-to-copper contact surface? ECS LIVA Z (talk) 23:37, 2 May 2017 (UTC)[reply]

  • Copper dissolves slowly into the water. This is enough to have some effect in a closed-loop system where the dissolved copper hangs around for awhile and the total bacterial load is small. In swimming pools that use copper instead of chlorine or some other treatment, two small copper/silver electrodes are placed about an inch apart and a low DC voltage is applied to encourage faster ionization. The voltage is reversed about once every 5 seconds to prevent electrodeposition of other chemical compounds. A pair of one-pound electrodes lasts for several years in a 50,000 gallon pool. This is a much more demanding environment than most places where you would depend on just the passive dissolving from the heat exchanger. -Arch dude (talk) 01:52, 3 May 2017 (UTC)[reply]
Thanks! ECS LIVA Z (talk) 03:04, 3 May 2017 (UTC)[reply]