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December 19

Measurements

Can someone please explain the measurements in table 3.8? I want to know how much grams of Material were measured. What does ^gmr1, <g ml1, cmg ml-1 and c mean? Greetings, 2A02:2450:101E:4C6:1FB:5B2:95AF:7CBE (talk) 00:37, 19 December 2020 (UTC)[reply]

It might be optical character recognized poorly and the numbers are exponents and multiplying something by milliliters to the negative 1st power means the same thing as per milliliter but scientific papers don't seem to like stuff per unit for some reason, they find a way to do it by multiplication so you don't have to divide. Sagittarian Milky Way (talk) 00:51, 19 December 2020 (UTC)[reply]

It was supposed to be "μg ml^-1", that is "micrograms per milliliter". See the original here:

https://books.google.com/books?id=1Fdcpj-UIqIC&lpg=PP1&pg=PA96#v=onepage&q&f=false

-- ToE 02:43, 19 December 2020 (UTC)[reply]

1 microgram per milliliter is, of course, equivalent to 1 milligram per liter, and to 1 gram per cubic meter. -- ToE 02:49, 19 December 2020 (UTC)[reply]

Post-surgery examination question

If someone gets a bilateral epididymectomy and a bilateral removal of the entire scrotal part of their vas deferens, is there any way for them to physically check, say, a couple of/several months or a year or a couple of/several years later what exactly the situation is in regards to those parts of the body? As in, has any abdominal vas since regenerated and expanded into the scrotum? Did the rete testis produce extremely long epithelial tubules where the epididymis used to be attached to it? Et cetera.

For instance, would an extremely high-definition ultrasound actually work for this? Futurist110 (talk) 02:06, 19 December 2020 (UTC)[reply]

If your s.o. has a child on the way, but you had a vasectomy, they sell paternity tests at Walgreens for $29. Just need a few hairs from the baby. That said, I recall reading that sperm cells can make it across quite a bit of scar tissue and gaps. In sperm counts of men vasectomized less then five years perviously, there are some viable sperm. One would have to go to get a sperm count done. Abductive (reasoning) 09:30, 19 December 2020 (UTC)[reply]

- They actually are on offer for $14.99 Source: https://www.walgreens.com/store/c/homedna-paternity-test-kit/ID=prod6364676-product. But notice: that's not the test per se. It's just a kit for collecting samples so you can send it to a lab for testing. (which cost +$140). Also notice: it's not done with hairs, but with cheek swabs. These are guaranteed to contain viable DNA. Hair might not contain any. --Bumptump (talk) 00:40, 20 December 2020 (UTC)[reply]

Why don't epithelial tubules grow out of the foreskin area after one gets one's foreskin removed?

Why don't epithelial tubules grow out of the foreskin area after one gets one's foreskin removed through circumcision? Futurist110 (talk) 05:54, 19 December 2020 (UTC)[reply]

Because you are not a magic alien that grows tubules like hairs. I have never seen tubes from my circumcision wound. Sagittarian Milky Way (talk) 16:08, 19 December 2020 (UTC)[reply]

One does grow epithelial tubules out of one's vas deferens after it is snipped and a part of it is removed, though. Futurist110 (talk) 17:48, 19 December 2020 (UTC)[reply]

Are all blond people related by a common ancestor?

Science – i. e. genetics – states all blue-eyed humans share a common ancestor. But does that also go for blond people? I was unable to find profound evidence for this issue. Thanks in advance for any assistance. Best wishes--Hildeoc (talk) 22:55, 19 December 2020 (UTC)[reply]

Probably not, there are blond people in Melanesia which is one of the 3 Oceania subdivisions and includes the island of New Guinea and stuff around there but not towards the direction of the other blond people. The gene doesn't have a common ancestor that is as of course every tree and cockroach is a cousin. Sagittarian Milky Way (talk) 23:21, 19 December 2020 (UTC)[reply]

By the way of course every tree and cockroach is a cousin of mine. 2003:F5:6F18:ED00:40E1:C2AF:BF93:B804 (talk) 12:05, 20 December 2020 (UTC) Marco PB[reply]

There's at least 2 different alleles that code for blond hair, one associated with the the TYRP1 gene that seems to be associated with blondness among the Pacific Islanders, and one associated with the KITLG gene that seems to be associated with blondness among European and Asian peoples. Both of these seem to be Single-nucleotide polymorphisms, meaning it is highly likely that each of them is due to a single mutation in history, and thus there would be a single ancestor as in blue eyes. So, it has evolved at least twice, and there would be a single ancestor for each of the two, but this is just me reading the information in the article Blond. --Jayron 32 13:13, 21 December 2020 (UTC)[reply]

In principle, there could be many mutations that impair the production of melanin in either hair or eyes; but even if there's only one, how safe is it to assume that it happened only once? —Tamfang (talk) 01:51, 26 December 2020 (UTC)[reply]