Wikipedia:Reference desk/Archives/Science/2015 December 28

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December 28[edit]

Microaggression theory[edit]

Don't know whether this goes here, however over at Microaggression theory there is someone who keeps claiming that "microrape" is a fourth form of microaggression. I cannot find it anywhere even in the Charles paper that they keep insisting it's in. I rather suspect the term could be another citogenesis incident! Any info would be greatly appreciated on this. Thanks! --MurderByDeletionism"bang!" 00:18, 28 December 2015 (UTC)[reply]

Microrape is of no use here. But it might need to be updated, if the claim is right. --Scicurious (talk) 01:01, 28 December 2015 (UTC)[reply]
Further note: the inclusion of microrape is possibly trolling. And there is no mention of it on the abstract of the source (that is, Charles and Rouse Arndt's article). The only source seems to be wikipedia itself, so I am removint it until someone gets a better reason to include it.--Scicurious (talk) 01:08, 28 December 2015 (UTC)[reply]
According to Google Scholar, the term does appear in the Charles and Arndt article (and in Patton, Tracey Owens, and Julie Snyder-Yuly. "Any Four Black Men Will Do Rape, Race, and the Ultimate Scapegoat." Journal of Black Studies 37.6 (2007): 859-895., and in the short story "Ghosts" (2007) by Charles Baxter), but the full text of both papers requires a subscription. Charles and Arndt's citation of the term to the original Sue paper seems to be incorrect, but they do (apparently) use it. Tevildo (talk) 10:00, 28 December 2015 (UTC)[reply]
The only part in the Patton, Tracey Owens, and Julie Snyder-Yuly article where microrape is mentioned appears to be:

A textual analysis of the interview statements allows one to see how in this case study of rape and race, larger macrocontext mythologies emerge. The textual analysis of the newspaper articles and the participant statements illuminate the connection between macro- and microrape and race events.

there is also a bunch of stuff like:

Although the student interviews cannot be generalized to all rape and race contexts because of small sample size, the student interview responses spoke to both micro- and macrocontext rape and race situations.

And a bunch of other references to micro and macrocontext. While I'm not certain I understand what the paper is saying, not having read it, I think by micro it means a specific incident and macro it means the general myths and problems that are common perhaps partially because of the microcontext. See e.g.

This lack of knowledge could demonstrate the reluctance of the university, media, and campus police to move this case from a microcontext myth (all participants knew that Robb faced criminal charges) to challenging a macrocontext myth (none of the respondents knew what happened after Robb faced criminal charges and the impact on African men and rape survivors).

and

Although the microcontext case was solved, there was no conclusion to the macrocontext myths that remained alive, even after the crime proved false.

In other words, micro-rape as used in that article has nothing to do with microaggression or what's talk about in the microaggression article.
Nil Einne (talk) 12:22, 28 December 2015 (UTC)[reply]
As for the second one, well AFAICT it's what the title I would suggest namely a short story about ghosts so not really an RS for any general idea. But in any case, it appears to be referring to something different to that described in our article. The only reference is:

A man given to generalizations might launch into nonsense about desperation, seeing a single mom with a baby boy, the two of them living in her father’s house, temporarily. Eric pulled hard at her bangs. She was trembling. Her hands shook. The visitation felt like . . . like what? Like a little big thing—a micro-rape.

I wouldn't exactly describe the previous communication with the ghost as prurient and the references to the woman's sexuality I noticed include an ex-husband and a baby from an ex-boyfriend later married man she had relationship with.
In other words, even ignoring it's fiction and not an RS, it's not referring to what's referred to in our article anyway.
Nil Einne (talk) 12:15, 28 December 2015 (UTC)[reply]
As for the Charles and Arndt article, you're correct it does use it. In particular:

Central in this experience is the presence of microaggressions endured in the workplace (e.g., Dispenza, Watson, Chung, & Brack, 2012), often presenting a metaphorical obstacle course of microassaults, microinsults, microinvalidation, and microrape (Sue et al., 2007) for those who openly identify as LGBTQ persons.

the only other reference to rape is a quote:

I’ve run into a lot of gay and lesbian citizens, and I think after showing them or telling them, “It’s okay to tell me that you are” that they feel more comfortable saying “Yeah, I’m a gay man and this guy raped me or I was beat up” or “I’m a lesbian and I was beat up because of . . . .” (Ryan)

and there's no reference to "prurient" nor to "heteronormative". So presuminggiven it's correct and "Sue, D. W., Capodilupo, C. M., Torino, G. C., Bucceri, J. M., Holder, A. M. B., Nadal, K. L., & Esquilin, M. (2007). Racial microaggressions in everyday life: Implications for clinical practice. American Psychologist, 62, 271-286." doesn't refer to micro-rape (which I expect), our article's definition of the term is suspect. Given that the only source that uses it any any way possibly related is not only linking it to a source which doesn't use it, it also doesn't define it.
Nil Einne (talk) 12:31, 28 December 2015 (UTC)[reply]
Okay as a final comment, I too can't find microrape (or anything about rape) anywhere in the Sue et al paper, which is available for free here [1] Nil Einne (talk) 12:36, 28 December 2015 (UTC)[reply]
I think that's a fair summary. The word appears in the Charles paper, cited to the Sue paper; however, the word does not appear in the Sue paper, and the definition does not appear in any reliable source. There does not seem to be a case for including it in our article. Tevildo (talk) 14:16, 28 December 2015 (UTC)[reply]

Why does "benzylamine hydrochloride" point to "Motion sickness"?[edit]

Why does "benzylamine hydrochloride" point to "Motion sickness" in Wikipedia?

One is a chemical; the other is a medical condition.

66.45.157.27 (talk) 01:02, 28 December 2015 (UTC)[reply]

It seems it's wrong.--Scicurious (talk) 01:13, 28 December 2015 (UTC)[reply]
Benzylamine hydrochloride redirects to Motion sickness#Medication, probably because the chemical is apparently a treatment for the medical condition. I'm not a subject matter expert, but https://www.google.com/search?q=benzylamine+hydrochloride+and+motion+sickness suggests that this is the case, eg John Glenn's medical kit included "benzylamine hydrochloride for motion sickness".
The target should probably mention that chemical (because of the redirect), if it is still used for that purpose (and a suitable ref can be provided). Mitch Ames (talk) 01:20, 28 December 2015 (UTC)[reply]
Yes, it should. Maybe it did at the time of the redirect. Presumably the redirect was done to avoid having to parrot that section of the main article. ←Baseball Bugs What's up, Doc? carrots→ 01:58, 28 December 2015 (UTC)[reply]

As a chemist, I would expect benzylamine hydrochloride to point to the benzylamine page, as amines are frequently stored / used as salts (much more stable as not vulnerable to N-oxidation) and the motion sickness medication is simply the HCl salt of benzylamine. That page should then have mention of the salt and its use and a link to the page on motion sicknes. EdChem (talk) 02:06, 28 December 2015 (UTC)[reply]

I have updated the benzylamine article, and think that benzylamine hydrochloride should be redirected to the Benzylamine#Salt. Any objections / comments? EdChem (talk) 06:15, 28 December 2015 (UTC)[reply]
I agree - redirecting to Benzylamine#Salt makes more sense. Mitch Ames (talk) 07:05, 28 December 2015 (UTC)[reply]

The Wikipedia-centric answer is "because someone pointed it there". Anyone can edit the site. Someone probably saw there was no article, and didn't feel up to writing one, but thought it would be useful to at least point it somewhere. Unless a redirect is protected you can just go ahead and edit it (even if you're not logged-in). To be fair, you have to know how to actually get to the edit screen for the redirect page, which you probably don't if you don't know your way around MediaWiki. Wikipedia:Redirect will tell you how to do this and other useful information. --71.119.131.184 (talk) 22:55, 28 December 2015 (UTC)[reply]

Target of redirect changed to benzylamine#salts per this discussion. EdChem (talk) 01:38, 29 December 2015 (UTC)[reply]

The one who created the original redirect is still active, so he could have been asked about it. ←Baseball Bugs What's up, Doc? carrots→ 21:37, 29 December 2015 (UTC)[reply]

Which algorithm to use[edit]

I need some guidance regarding my problem Assume a triangle lying on a plane making certain angle with xy plane,displaced in z axis. The triangle is of constant area whose area and length of vertices are constant. All three vertex points of triangle can displace in all three axes maximum by 12mm from its original position.

problem
problem

only input that i have: I know the point where the normal passing through centroid of the triangle intersects xy plane. using any algorithm can i predict the vertices of triangle with given inputs. Like neural network,genetic algorithm etc Any help and guidance how to approach the problem is welcomed SD — Preceding unsigned comment added by Sameerdubey.sbp (talkcontribs) 09:07, 28 December 2015 (UTC)[reply]

Do you know the vertex lengths on the triangle? Do you know the original position? You should be able to solve this with linear algebra. However even if you have the normal to the centroid of the triangle hitting the X-Y plane, the triangle can rotate about that line, so it cannot be uniquely solved. Neural networks need training, so you cannot throw a text description at it, and a set of coordinates and expect an answer! Graeme Bartlett (talk) 11:38, 28 December 2015 (UTC)[reply]
I agree that you need to ask this again more carefully. It seems like the triangle could rotate, and can also move back and forth along the normal line by up to 12 mm in either direction. But your language leaves much room for confusion: a vertex is a point, so what is a vertex length? Do you mean the length of a side of the triangle? You write the triangle lies on a plane, I'll call it "P", that makes a certain angle with the xy plane - if that were all you knew, P could have any number of orientations, but since you say you know the intersection of the normal line, you actually know that P is perpendicular to a certain line. Do you also know where P intersects xy? (in which case the triangle can't move back and forth on the normal line). And last but not least -- what are the "given inputs"??? Wnt (talk) 13:20, 28 December 2015 (UTC) Oh, yeah, and laster than that: we have both math and computing desks, either one of which is more likely to get you a real solution once you explain the problem well enough. Wnt (talk) 13:22, 28 December 2015 (UTC)[reply]
As far as I can see, you don't have enough information. You want to know where the three corners are, but since, as you say, all three corners can move in all three axes, and since the triangle is a rigid object (when you say "length of vertices" I presume you mean "length of sides"), it will have six degrees of freedom of motion which need to be determined. But you seem only to have information about two degrees of freedom (the point where the normal passing through centroid of the triangle intersects the XY plane). Is this related to a computer vision problem? If so, then if you had a 2D image of the triangle from some vantage point, then you would have the ability to determine three 2D positions, one for each vertex, and with those six degrees of freedom, determining the positions of the vertices in 3D would then be a relatively simple inverse problem in 3D perspective -- albeit a quite noise-sensitive one, if I recall correctly-- The Anome (talk) 13:50, 28 December 2015 (UTC)[reply]


Thanks a lot friends for your feedbacks.Yes this is a computer vision problem.I am thinking to make 3d transformation of the triangle with the normal. 112.133.223.2 (talk) —Preceding undated comment added 10:08, 29 December 2015 (UTC)[reply]

Bleach and vinegar reactions[edit]

Good morning. I have an answer about an involuntary reaction happened in my home. For error I mixed liquid vinegar and bleach during an house-cleaning, and the reaction produced a fizz (probably molecular chlore, Cl2.

So, with my little chemistry knowledge the reaction with acetic acid and sodium ipochlorite is this:

CH3COOH + NaClO ---> CH3COONa + HClO

Where are produced sodium acetate and ipochlorous acid.

The answer is: how does Cl2 develop? What is the real reaction and what happened at the two reagent? Thank you so much.

P.S. I say I'm sorry for my english, but I'm Italian

--79.51.143.66 (talk) 15:44, 28 December 2015 (UTC)[reply]

Try Hypochlorite#Acid reaction. EdChem (talk) 15:50, 28 December 2015 (UTC)[reply]
It's a good Italian lesson. Milano è meglio di Napoli, anyway.
Well, the solution of the problem is here, in the Italian version of Reference desk (called Oracolo). Thank you very much, and happy new year. --95.232.144.166 (talk) 17:01, 29 December 2015 (UTC)[reply]

Hydration retardant[edit]

Why would anyone want to slow down the hydration process of cement using admixtures since most reduce compressive strength? — Preceding unsigned comment added by 82.132.217.179 (talk) 17:06, 28 December 2015 (UTC)[reply]

See this article. According to it: "Use of retarders is beneficial for:
  • Complex concrete placement or grouting
  • Special architectural surface finish
  • Compensating the accelerating effect of high temperature towards the initial set
  • Preventing cold joint formation in successive lifts."
In other words, there are times when it's more important for the cement not to set too quickly, rather than have the maximum possible strength. Tevildo (talk) 17:57, 28 December 2015 (UTC)[reply]

Disorder name sought[edit]

Hello,

Have you guys seen the movie called The Exorcism of Emily Rose?

There is a scene where, before she was fully demonically possessed, she was disturbed by the surrounding noises, e.g., cutlery noises and so on. I would like to know the scientific terminology of that particular disorder - a person who is disturbed by too much surrounding noise(s) basically.

Regards.

Space Ghost (talk) 21:30, 28 December 2015 (UTC)[reply]

Extreme sensitivity to stimuli in general is Hyperesthesia, and to sounds in particular is Hyperacusis. See this article on the NHS website. Tevildo (talk) 22:02, 28 December 2015 (UTC)[reply]
I'll read through, thanks. -- Space Ghost (talk) 21:20, 29 December 2015 (UTC)[reply]
See also Misophonia. Edison (talk) 22:13, 29 December 2015 (UTC)[reply]
Okay. -- Space Ghost (talk) 18:17, 30 December 2015 (UTC)[reply]