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October 5

Oil and condom breakage

How do condoms break when subjected to oil? Do they still pop and cause a large tear or is an oil break more likely to be smaller and unnoticed? — Preceding unsigned comment added by 194.66.246.116 (talk) 01:22, 5 October 2014 (UTC)[reply]

While this desk cannot and will not provide anything resembling medical advice, we can provide reliable sources, such as:

Voeller, B; Coulson, AH; Bernstein, GS; Nakamura, RM (1989 Jan). "Mineral oil lubricants cause rapid deterioration of latex condoms". Contraception. 39 (1): 95–102. PMID 2535978. {{cite journal}}: Check date values in: |date= (help)

—71.20.250.51 (talk) 04:21, 5 October 2014 (UTC) Edit:04:27, 5 October 2014 (UTC)[reply]

Not medical advice. I'm doing a research report on condom use.

According to the article, oil destroys the elasticity of latex. You could run an experiment or two and let us know what happens. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:26, 5 October 2014 (UTC)[reply]

Crude oil as medicine

What physiological effects can come from direct consumption of small quantities of crude oil by the human body? No, not by me; it's a historical question.

Oil Creek State Park is located in the area near the Drake Well, the centerpoint for the first US oil boom. Our article on the park notes that there were pre-boom natural oil springs, for which the "main use to that time had been as a medicine for both animals and humans". When I consider "crude oil" and "medical" together, the first topic that comes to mind is "reasons for calling the poison control center", but obviously administering oil either was harmless, or it caused harm that wasn't immediately evident; traditional medicines can't become traditional if they typically cause short-term problems. Nyttend (talk) 04:37, 5 October 2014 (UTC)[reply]

There's also the possibility that it was used to induce vomiting. Like syrup of ipecac. Dismas|^(talk) 06:32, 5 October 2014 (UTC)[reply]

I'm guessing that natural crude oil is less harmful than processed crude, with all sorts of toxic additives. And note that petroleum jelly (such as Vaseline) has been used medically for many decades. It's normally used externally, but our article does talk about using it internally, as well. As far as drinkking it, that might work as a cure for constipation. I believe mineral oil is the most common petroleum distillate oil used for that purpose. StuRat (talk) 16:49, 5 October 2014 (UTC)[reply]

Refined oil is likely to contain fewer chemicals than crude. Crude oils (there are different kinds, with differenct compositions) contain hundred of chemicals, some of which are highly toxic. There's some information in the National Library of Health. DuncanHill (talk) 17:00, 5 October 2014 (UTC)[reply]

That rather depends on the purpose of the refinement. If not intended for medical use, they may add all sorts of nasty chemicals. Lead was originally added to gasoline, and some of it's replacements are almost as bad. StuRat (talk) 17:07, 5 October 2014 (UTC)[reply]

Refining removes all sorts of chemicals - the objective of refining is to remove unwanted components and to standardise the mixture. Certainly other chemicals will be introduced to achieve the desired properties, butt to say that natural crude is likely to contain fewer chemicals than refined is just silly. Crude oil - like lots of other unprocessed natural materials, is toxic. Petroleum jelly is very highly refined to make it safe for use. DuncanHill (talk) 17:11, 5 October 2014 (UTC)[reply]

Indeed. StuRat, I think you ought to read about petroleum refining (...and leaded gasoline, while you're at it). Tetraethyllead contains, but is not the same as, metallic lead.

For the most part, crude oil goes into the refinery as the primary input natural resource. Everything else that is used in downstream chemical reactions - like say, the hydrogen gas used in certain polymerization processing - comes out of the crude oil at some early stage in the refinery.

Even the energy used for the refining often comes from the crude oil (and atmospheric oxygen). Conceptually, crude oil is a primary energy source and a raw material. If you hypothetically wanted to add some "nasty additive," where would you get that chemical from? Presumably you would import it from some other refinery?

Nimur (talk) 21:55, 5 October 2014 (UTC)[reply]

Where does tetraethyllead come from ? Tobacco similarly has some rather nasty additives when made into cigarettes, but nicotine can also be extracted from it, which isn't particularly harmful, by itself, although it is addictive. My point is that processing can either make a natural product better or worse for people, depending on the goal of that processing. StuRat (talk) 04:29, 6 October 2014 (UTC)[reply]

"TEL is produced by reacting chloroethane with a sodium–lead alloy." Cursory research seems to indicate that InnoSpec is the only provider of these additives. But these octane additives are not usually added to crude oil in the refinery: such processing by distributors usually happens downstream. Nimur (talk) 04:50, 6 October 2014 (UTC)[reply]

A couple of papers on use of crude oil in traditional medicine - Crude Oil Poisoning in a 2 Year Old Nigerian - A Case Report and Uses of crude oil as traditional medicine: a survey of mothers in a rural clinic in South-south Nigeria. PubMed abstract. DuncanHill (talk) 17:04, 5 October 2014 (UTC)[reply]

See also Snake oil, which refers to the (disputed) theory that the name comes from the medicinal use of crude oil (rather than oil derived from snakes). Tevildo (talk) 18:48, 5 October 2014 (UTC)[reply]

I think the article is barking up the wrong tree there. See q:Snake oil, which includes a great quote about snake oil, skunk oil, angleworm oil, &c. (Raccoon oil was also a thing) The "angleworm poultice" mentioned in the first episode of The Knick was presumably akin to this. Because animal oils might contain unusual fatty acids, I would not rule out the possibility of beneficial effects without extensive testing; folk remedies certainly don't work always, but they work often enough to deserve our attention, or to serve as a preferable substitute to the placebo. Wnt (talk) 03:16, 6 October 2014 (UTC)[reply]

Erections and Transitioning From Male to Female

Is there any way for someone who (physically) transitions (while still keeping her penis, obviously) from male to female to indefinitely continue getting erections?

For example, let's (hypothetically, if necessary) say that a gender-fluid/non-binary/et cetera person who was assigned male at birth wants to (physically/bodily-wise) transition from male to female but also wants to indefinitely be able to continue getting erections (using her penis, obviously). Is there any way for this individual to do this?

And Yes, this is a completely serious question. Futurist110 (talk) 07:03, 5 October 2014 (UTC)[reply]

I would think so, yes. Presumably you mean that the loss of testosterone due to castration will cause impotence. Well, they could take testosterone supplements, although that might also cause other masculine traits like facial hair. Perhaps a physical impotence cure might work, like the penis pump. StuRat (talk) 17:02, 5 October 2014 (UTC)[reply]

This runs afoul of philosophy. What does it mean to transition to a female? If the definition is loose enough, he might simply announce "I'm a girl now!" and it's a success. If the definition is stringent, someone will object that this particular decoration doesn't fit with the ensemble. You might make this into an answerable question if you narrow down what you're thinking of more carefully -- for example, guys can have gynecomastia for a pleasant feminine look up top while retaining full function. (Which I presume is what a herma of Aphrodite would look like it portrayed) Wnt (talk) 03:21, 6 October 2014 (UTC)[reply]

Molecular thermodynamics

If there is anyone around used to reading technical articles on this subject or similar subjects with many abbreviations and figures in the prose, could you help with this DYK review? We need to confirm ~~that it~~ this it says, in its own words, "thermal energy at room temperature can _{spin a molecular gyroscope at more than 1,000,000,000,000 times a second}". (specifically the thermodynamic bit) (try searching the page for 1012 which will bring up ten to the power = trillion) And if it doesn't say exactly that, can you suggest a similar sentence with the correct info? ~ R.T.G 13:44, 5 October 2014 (UTC)[reply]

I may be that I'm misunderstanding this, but the link given above goes to a 1993 paper, while the link in the article (supporting the hook) goes to a 2007 paper. I don't myself understand it well enough to know if the paper actually supports that speed - although it does say "The magnitude of the preexponential factor is in good agreement with a rotational frequency of 2.4 x 10¹² s-1 calculated for a phenylene free rotor from its moment of inertia along the 1,4-axis", I'm not clear that that's the same thing. Mikenorton (talk) 15:44, 5 October 2014 (UTC)[reply]

Yes it was the PDF sorry. Ah you have spotted something. We were agreed with one trillion, but it's actually 2.4 trillion isn't it... thanks for that. But yeah it's mainly the thermodynamic part we weren't 100% on so if any more want to try, ~ R.T.G 17:39, 5 October 2014 (UTC)[reply]

Kelvins per second

Is there any special name for a change in temperature?? I mean like, velocity is the name for what we measure in meters per second. This question is about a special name for what can be measured in kelvins per second. Georgia guy (talk) 15:39, 5 October 2014 (UTC)[reply]

Heating (or cooling) rate?--86.182.55.229 (talk) 16:44, 5 October 2014 (UTC)[reply]

Thermal velocity sounds like it, but that means something else. StuRat (talk) 16:57, 5 October 2014 (UTC)[reply]

Have a look at heat rate and heat flux. We tend to look at changes in heat rather than temperature, for that sort of thing. I haven't encountered an interest in K s^-1. 86.146.28.159 (talk) 17:01, 5 October 2014 (UTC)[reply]

There are definitely contexts in which this is a quantity of interest, such as melt spinning, but I would imagine that it is simply called cooling rate. —Quondum 23:33, 5 October 2014 (UTC)[reply]

aromatic nitration

why doesn't aromatic nitration occur in nature? This is not a homework question. --2602:252:D65:D2F0:A949:3405:ACFF:41DE (talk) 15:49, 5 October 2014 (UTC)[reply]

The usual nitrating agents for electrophilic aromatic substitution, such as the nitronium cation, are pretty reactive. Nature doesn't seem to use many such highly reactive intermediates if there are alternatives because they require lots of energy or highly reactive precursors to create and can react with so many substrates other than the intended one. And the nitroaromatic compounds are fairly reactive (high energy, especially prone to reduction by many other substances in biological environments that lead to toxic products), so it's a self-perpetuating process of sorts (not easily formed, therefore no need to protect against their presence, therefore if they are formed they are problematic, therefore they are not formed).

At least that's a quick and general first-principles theory. But then, Nature does what Nature does, not what one theory says, and we're stuck trying to make theory fit facts rather than vice versa:) For a review article noting that there are some biological nitration processes, see:

Ju, Kou-San; Parales, Rebecca E. (2010). "Nitroaromatic Compounds, from Synthesis to Biodegradation". Microbiol. Mol. Biol. Rev. 74 (2): 250–272. doi:10.1128/MMBR.00006-10.

DMacks (talk) 19:49, 5 October 2014 (UTC)[reply]

Dry density and dry unit weight

Are these 2 terms equal in geotechnics? — Preceding unsigned comment added by Clover345 (talk • contribs) 17:01, 5 October 2014 (UTC)[reply]

Not quite the same, according to this, and this. Mikenorton (talk) 17:14, 5 October 2014 (UTC)[reply]

I see. So one considers Gravity. Also, is it possible to calculate the bulk density from only mass, moisture content and dry unit weight? I assumed a volume would also be required. Clover345 (talk) 17:27, 5 October 2014 (UTC)[reply]

Is scrupulosity a culture-bound OCD disorder?

So far, I have read articles about this form of OCD, but they are usually concerned with a single deity, sin, and punishment. How does this type of disorder manifest in East Asian cultures or non-theistic cultures? 71.79.234.132 (talk) 22:19, 5 October 2014 (UTC)[reply]

Our article lists several references; from these, I went to PubMed and found another paper by one of the authors: the Penn Inventory on Scrupulosity (2002). This is a non-diagnostic research survey that has been used in various studies to identify scrupulosity in test populations. At least one reviewer in one follow-up study found that they needed to remove several line-items from the originally-published survey to make it applicable enough for a different, broader survey population at a different university: regarding validity of the Penn Inventory of Scrupulosity (2006). Our own Wikipedia article cites a different research approach that compared the scrupulosity of Muslims to that of Christians.

So, it looks like there has been some prior peer-reviewed research into the cultural aspects of this diagnosis. A lot of the stuff that pops up in PubMed is about the skew between Protestants and Catholics. A lot of the other articles that pop up, particularly the ones in theological reviews (as opposed to psychological reviews) question the legitimacy of treating this phenomenon as a psychiatric (medical), rather than a theological, concern. (For example, I found Transference and Scrupulosity (1963) on JSTOR, which I find to be a better general repository of non-scientific research). It presents a fascinating counterpoint, from the view of a theological scholar (... well, from some kind of scholar... like all interesting stories about god and morality, the CIA was involved). The moral of this story: you'll get a different answer depending on where you look and who you ask! (Perhaps there's a religious double-meaning attached to that statement?)

Fascinating topic! From my readings, I would recommend Scrupulosity disorder: an overview and introductory analysis (2007) as a start, and then proceed from there.

Nimur (talk) 04:21, 6 October 2014 (UTC)[reply]