Wikipedia:Reference desk/Archives/Science/2015 September 5

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September 5

Amyl nitrite and catalepsy

Is amyl nitrite (or can it be) an effective treatment for catalepsy? Not asking for myself; this chemical is a doctor's remedy-of-choice when faced with an alleged cataleptic in a Sherlock Holmes story, "The Adventure of the Resident Patient". Nyttend (talk) 03:53, 5 September 2015 (UTC)

Possibly, from the article you linked, " Alkyl nitrites are a source of nitric oxide, which signals for relaxation of the involuntary muscles. Physical effects include decrease in blood pressure, headache, flushing of the face, increased heart rate, dizziness, and relaxation of involuntary muscles" Of course, catalepsy is contraction of skeletal muscles, which are not directly mentioned, but if the effect is similar, it could be a reasonable treatment. But that's just a WAG based on what is mentioned in the Wikipedia article. --Jayron32 04:00, 5 September 2015 (UTC)

Mechanical component that reduces rotation by force x

What is a mechanical component that can be set to reduce rotation of an axle by a force x? That's different from a brake, that applies all it's force to an axle to stop rotationl

Imagine a pulley hanging from the ceiling with a cable attached to and wound around it. Can a device be set to allow you to hang 1, 5 or x kg on the cable without unwinding it? That is, it increases the resistance to rotate of the axle/pulley.--3dcaddy (talk) 08:32, 5 September 2015 (UTC)

A brake is not neccessarily an "all or nothing" mechanism, as anyone who has ever used a bicycle, motor vehicle or fishing reel would know. In fact fishing reel brakes are designed to do exactly what you describe, exert a fixed braking force on the reel as it unwinds. Roger (Dodger67) (talk) 09:33, 5 September 2015 (UTC)

OK, you don't have to go 100% using a brake. But you can't set a number x on it either. I'd like to know the name of the component, (brake or whatever it's called) that can be set to brake (or whatever it's called) an axle by x. The fishing reel brake is a good example in the right direction. --3dcaddy (talk) 09:37, 5 September 2015 (UTC)

Such a device is known (formally) as a tool balancer, and informally as a "skyhook", although we don't seem to have an article on the subject. See this Google search for a selection. Tevildo (talk) 10:04, 5 September 2015 (UTC)

How about governor? It has weighted arms that move outwards due to centrifugal force and keep the rotational speed more or less constant. Akld guy (talk) 12:15, 5 September 2015 (UTC) Edited for clarity. Akld guy (talk) 12:18, 5 September 2015 (UTC)

There isn't really one generic term for such a device, to answer the OP's question literally. A tool balancer is the device described in the question, which allows different weights to hang from a (stationary) axle. A governor will keep a (moving) axle at a constant speed. A prony brake will apply a constant torque to a moving axle. Various types of clutch are used to get constant torque from a moving axle. Tevildo (talk) 13:12, 5 September 2015 (UTC)

Wouldn't inertia damper be the generic term? 99.235.223.170 (talk) 14:38, 5 September 2015 (UTC)

A differential pulley has the nice property that the load stays where it is until you pull on it as shown in the diagram. (Unfortunately the article doesn't seem to mention this nice property which I find in "The New Way Things Work" by David Macauley p.56.)--Wikimedes (talk) 20:12, 6 September 2015 (UTC)

(Now it does.)--Wikimedes (talk) 20:24, 6 September 2015 (UTC)

Name this South African grasshopper

Steve the grasshopper

Found in Victoria West, Northern Cape, South Africa. Length about 100 mm or 4 inches.

Found out in the open around 1 p.m. today (sunny day in early spring) temperature around 20°C.

Roger (Dodger67) (talk) 11:35, 5 September 2015 (UTC)

My guess is Phymateus viridipes (check the pic in the infobox). The genus is highly variable if this is any indication. 99.235.223.170 (talk) 12:16, 5 September 2015 (UTC)

Incidentally, I found this by typing south african grasshopper identification in Google Image search and then just clicking on the first bug that looked like yours (the Jungle Dragon link) and proceeding from there. 99.235.223.170 (talk) 12:19, 5 September 2015 (UTC)

I'd say close but not quite there... The coloration is not the same, P. viripides has red tips on it's many bumps, the one here doesn't and conversely this one has dark brown to black joints and spots on it's legs, unlike viripides. It's also significantly larger, by about 30%. I think the genus might be the same but it's not the same species. Roger (Dodger67) (talk) 14:00, 5 September 2015 (UTC)

Certainly possible, but if our pictures are correctly identified, this one lacks the red tips as well. 99.235.223.170 (talk) 14:34, 5 September 2015 (UTC)

• He looks like a "Steve". I'm going to name him "Steve".  Done. You're welcome. --Jayron32 04:02, 6 September 2015 (UTC)

Refusal to acknowledge mental disability

We can't comment on your sister's supposed learning disability or mental illness nor on your mother's coercion. Seek legal and medical counsel. The following discussion has been closed. Please do not modify it.

My mother is convinced that my older sister is mentally healthy despite the fact that she has been diagnosed as having learning difficulty. This refusal to accept science has led to my sister ending up accumulating thousands of pounds in debt she can't pay back in university fees. My sister failed each subject after being forced to attend courses by my mother. I have also noticed that my mother refuses to acknowledge the existence of distinct personalities in humans. For example she does not acknowledge that some of my pet peeves are permanent and cannot be altered. So are there any citations on individuals whom refuse to acknowledge mental conditions. Otherwise refs on individuals who forsake scientific diagnosis in their family would help too. Especially refs on individuals who do it due to a perceived taboo associated with mental illness. 80.42.64.30 (talk) 16:03, 5 September 2015 (UTC)

"We don't answer (and may remove) questions that require medical diagnosis or legal advice". AndyTheGrump (talk) 16:05, 5 September 2015 (UTC)

I am asking for any sources, references or citations related to refusal to ackowledge mental conditions. I have clarified. 80.42.64.30 (talk) 16:09, 5 September 2015 (UTC)

While I can't comment on any particular case, I'd like to point out that medical or psychiatric diagnosis isn't always an exact science. People do sometimes get misdiagnosed; doctors/psychologists are only human and can make mistakes. It's not always a bad idea to get a second opinion, though, like Andy said, we can't comment on your specific case. - Lindert (talk) 16:20, 5 September 2015 (UTC)

There's no way to diagnose your family situation over the internet. However, you may find the article on Denial interesting. And being in denial, which is a very common human condition, has nothing necessarily to do with acceptance or rejection of science. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:28, 5 September 2015 (UTC)

Hi, one place to start is at Mental_disorder#Society_and_culture, which is a pretty good section, and has many relevant references.

For additional sources, here's some scholarly articles that I found on google scholar that are somewhat relevant to the framing of mental illness and the acceptance of diagnosis - . Some are full texts, some are just abstracts. For the latter, you can sometimes find a full PDF copy by googling the title, or you could ask for a copy at WP:REX. SemanticMantis (talk) 21:54, 5 September 2015 (UTC)

Note that refusal to believe a psychiatric diagnosis can be based on it being purely subjective. A more objective diagnosis, say with a PET scan showing a lack of glucose utilization in the part of the brain associated with memorization while studying, might be more readily accepted as proof, by such people. (I'm not recommending this procedure, only a doctor can do that.) StuRat (talk) 02:29, 6 September 2015 (UTC)

This is not a general question, but an accusation of mental illness and criminal neglect, both of which amount to defamation per se in Great Britain. Call the NHS and a solicitor. μηδείς (talk) 02:58, 6 September 2015 (UTC)

That sounds like legal advice. Are you qualified to say what defamation is in the UK? None of the above posts are anywhere near professional advice except yours ;) SemanticMantis (talk) 04:10, 6 September 2015 (UTC)