Wikipedia:Reference desk/Archives/Science/2015 September 26

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September 26

Are people with Asperger or autism more prone to stalking?

Is there any correlation between autism spectrum disorder (ASD), including Asperger's, and stalking? Intuitively, it makes sense to believe that the possibility exists, but was it scientifically researched? --Scicurious (talk) 00:22, 26 September 2015 (UTC)

Individuals with Asperger's are known to have great difficulty in pursuing romantic relationships, which is attested by many sources. I have only seen one paper that actually attempts to answer whether Asperger's sufferers are more likely to engage in stalking-like behavior. The authors believe the data answers in the affirmative, but they used a very small study population [1]. Perhaps someone has compiled crime statistics, but I have not found any. Someguy1221 (talk) 00:56, 26 September 2015 (UTC)

Speaking from personal experience, a degree of social ineptitude (even if not spectrum-related) can result in behaviour which to observers may resemble stalking. {The poster formerly known as 87.81.230.195} 185.74.232.130 (talk) 14:33, 28 September 2015 (UTC)

Musician's fine motor control vs. weight training

In theory, is there any reason for thinking that lifting very heavy weights could have a detrimental effect on fine motor control for musicians? I am thinking specifically of the very small movements involved in classical or fingerstyle guitar (which apparently should be completely free of tension, at least if you don't want RSI), but would also apply to piano. The question is more concerned with instruments that use fingers, less with those that use large movement from the elbow or shoulder ie. violin bowing hand or strumming guitar. 129.96.84.184 (talk) 01:27, 26 September 2015 (UTC)

Found two specific examples, but both violin players.

"Vengerov stopped playing in 2007, citing both professional malaise and a weightlifting injury to his right shoulder that had plagued him since 2005" Source. Read somewhere that he was "pretty big into weight lifting". Didn't seem to hurt his technique before the injury.

Elizabeth Wallfisch says she overcame chronic RSI by working in the gym and lifting weights. (with the help of a physiotherapist) source

A piano forum where the question was asked, maybe some useful responses: link

Didn't find any studies; the question has been asked on other sites, mostly about "classical" instruments (piano and violin), about guitar not so much. On some fora the same question comes up every few months; if good sources/studies existed, you'd expect them to be mentioned in one of those topics. Read that some teachers recommend it, others advice against. And there was a rock guitarist who (supposedly) said he had to cut back on bodybuilding because it made him slower, but that's hardly the same as weight training. Can't tell you more I'm afraid... Ssscienccce (talk) 22:13, 26 September 2015 (UTC)

Thanks for taking the effort to gather those links. Yes, an injury would definitely be detrimental to musical ability. Part of the reason I hedged my question with 'in theory' is that there does seem to be a lack of evidence (outside the anecdotal). Of course, absence of evidence isn't necessarily evidence of absence. I have a strong intuition that the great weight I place on my fingers when I do pullups might not be great for the delicate movement of fingerstyle, but my intuition might just be baseless... The piano forum's take-away of 'it's fine, just don't overdo it' is probably not far off the mark. - The OP 121.45.141.164 (talk) 07:49, 27 September 2015 (UTC)

Yes, clearly didn't address the "in theory" part. I could speculate, but would probably come up with things you've thought of already, like adverse effects of more muscle mass, less feeling in your fingers, damage to tendons, loss of fine motor control... but perhaps the opposite is true, I simply don't know. Ssscienccce (talk) 01:37, 28 September 2015 (UTC)

Superconductor question

what is superconducter? discribe it — Preceding unsigned comment added by Shahjad ansari (talk • contribs) 03:28, 26 September 2015 (UTC)

"A superconductor is a material that can conduct electricity or transport electrons from one atom to another with no resistance." [2] You could also read our article on superconductivity for a better understanding. Rainbow unicorn (talk) 03:50, 26 September 2015 (UTC)

popullation

Q.which country has very high popullation density----Shahjad ansari (talk) 03:37, 26 September 2015 (UTC)

Macau or Monaco is the highest, depending on how you think of "sovereignty" or "country", see List_of_sovereign_states_and_dependent_territories_by_population_density. SemanticMantis (talk) 03:42, 26 September 2015 (UTC)

And depending on how you define resident. I am pretty sure many people count as Monacos population, but live elsewhere.--Scicurious (talk) 18:28, 26 September 2015 (UTC)

Can small plastic test tubes survive freezing with water in it?

I'm trying to buy a pack of small test tubes[3], fill them with water, and then freeze them. They come in two versions, polystyrene and polypropylene. Can either version survive the ice expansion? If they both can, which plastic will last longer under these conditions (repeated thawing and freezing of the water inside)?

I know that glass test tubes will crack, but I've never tried with plastic test tubes before, nor have I ever played around with test tubes this tiny. 731Butai (talk) 08:29, 26 September 2015 (UTC)

Those look like a strange choice of test tube for storing something at freezing temperatures. Anyway, either type of plastic would survive freezing. The expanding water would only burst the tube if you sealed it completely, and in the case of these tubes I suspect doing that would simply cause the top to pop off. My own experience with polypropylene test tubes is that they can survive effectively infinite freeze-thaw cycles. Not sure I ever worked with a polystyrene test tube, but polystyrene equipment is generally easier to destroy by accident, in my experience. Someguy1221 (talk) 09:16, 26 September 2015 (UTC)

See [4] Richerman (talk) 09:51, 26 September 2015 (UTC)

I've used plastic centrifuge tubes (similar to test tubes) that I have flash frozen water or water solution samples using liquid nitrogen on a regular basis in preparation for lyophilization. At first I was very concerned about breaking the tubes, but this has yet to happen. --OuroborosCobra (talk) 13:59, 26 September 2015 (UTC)

As per the articles, polystyrene is "brittle" while polypropylene is "rugged". My guess is both will hold up to a simple freeze, but if you're planning on dropping your sample and running a cart over it you'd be better off with polypropylene. Also, polystyrene (like styrofoam) is very susceptible to dissolve in something like xylenes, while polypropylene resists a variety of such exposures, and likewise polypropylene may even survive an autoclave while polystyrene wouldn't. The only real advantage I can think of at the moment for polystyrene is that it is nice and clear and you can carefully watch what's going on if you're, say, sucking a layer out of a tube without pulling up material from the phase interface, while polystyrene tends to be cloudy though certainly not opaque. Wnt (talk) 09:28, 27 September 2015 (UTC)

Question 1: Ton Of Gay Aspies?

From my own observation, adolescent and adult males with Asperger syndrome are at least twice as likely as their "typical" counterparts to be gay. Any research to affirm this? Theskinnytypist (talk) 09:30, 26 September 2015 (UTC)

I don't see that anyone has looked in the case of Asperger's. People have looked in the case of autism in general (such as here), but never with a large number of patients. There are more studies than that that are even smaller and come to different conclusions, so the answer is "unknown". Someguy1221 (talk) 10:06, 26 September 2015 (UTC)

Never went through my mind any association between Asperger's and being gay. Quite in contrary, it's more like gay men always are in the mood "to express themselves."--Scicurious (talk) 18:23, 26 September 2015 (UTC)

Question 2: Getting To The Bottom Of Health Effects

My other question is about health (hopefully I've come to the right place) - specifically obesity. For the entire 21st century, the media have invariably done two things in regards to it:

1. Focused on its effects on society
2. Used language that implies that it's a horrible thing

I've flirted with the bear and chub scene for a couple years now, and my desires prevent me from agreeing with the latter. Prompted by a conflict between public health announcements and the associated movement, these (unable to find good describing word) have been burning in my head for several weeks:

• The mere presence of fat on one's body doesn't make someone unhealthy, but rather the lifestyle choices that often go with it. True or False?
• I've heard not just these guys, but even some covet members of the health industry, say that an overweight person who exercises regularly would be somewhat healthier than a fit person who gets no exercise.
• Eating a balanced diet is better than eating one high in fat. True or False?
• I am especially skeptical of reports of life expectancy winding down like an old clock, as many overweight or obese people live about as long as people of "normal weight."

What is the real story?? Theskinnytypist (talk) 09:53, 26 September 2015 (UTC)

Obesity is one of the leading preventable causes of death worldwide. That article is quite detailed and well referenced. Have you read it?--Shantavira|^{feed me} 10:23, 26 September 2015 (UTC)

There's nothing covet about your second bullet point. These's some evidence that complete inactivity is worse than being overweight or even being obese [5] [6] and this is often discussed outside journal articles particularly when a study or whatever has just been released. [7] [8] [9] [10] However I think it's fairly unlikely that anyone who does absolutely no exercise, even a teen or young adult, will be consider "fit" under most normal definitions of the term fit, even if they have a weight in the healthy range (and the fit isn't normally a synonym for that).

Note also a lot of the strong evidence tends to be looking at exactly that, people who get almost no exercise. (E.g. In the first study, a brisk walk of 20 minutes every day would be enough to put people outside of the worse category.) If instead of a nearly completely sedentary lifestyle, you're comparing, for example, an obese person who does a 40 minutes brisk walk every day vs a person in the healthy weight range who does a 20 minutes brisk walk every day, you'll need to look more carefully at the evidence. I suspect it's probably not that strong either way.

There's also debate over whether a weight in the healthy range or increasing activity should get more emphasis [11], however I think most researchers in the field would agree that ideally both should get some emphasis.

I won't say much more about your other points since I'm lazy to dig up sources and I think it's the sort of thing that really needs them, but bear in mind the evidence for most dietary and lifestyle factors is generally based on longitudinal study and similar. The results of such studies have to be treated with care compared to the gold standard, i.e. double blind testing, as it's very difficult to properly account for all the possible interacting confounding factors. Hence it's particularly important you concentrate on good multistudy reviews (like Cochrane Collaboration reviews rather than single studies. Also there's recognition that weight/BMI is at best a weak datapoint. At the very least, you have to consider stuff like race (ancestry), sex and age, but ideally you want to look at body fat percentage, where it's distributed etc. Unfortunately these are more difficult to obtain or sometimes, understand.

Nil Einne (talk) 12:56, 26 September 2015 (UTC)

There is good evidence when it comes to extreme obesity, see the NIH study.

I should point out that some of the sources used in the mortality section of the Obesity article are outdated, and in particular the one claiming up to 365,000 deaths per year due to obesity in the US has been challenged in later publications. Ssscienccce (talk) 13:42, 26 September 2015 (UTC)

"The mere presence of fat on one's body doesn't make someone unhealthy, but rather the lifestyle choices that often go with it. True or False?"

Of course, everyone has fat on their body, unless they have a metabolic disease. (Having no fat makes you look like a skeleton with skin, so you don't want that.) But, I suspect you meant to ask about excess fat, which does make you unhealthy. Specifically, it seems to lead to adult-onset diabetes. Lifestyle choices are also important. StuRat (talk) 16:20, 26 September 2015 (UTC)

"Eating a balanced diet is better than eating one high in fat. True or False?"

Balanced as far as calorie sources, in protein, carbs, fat (and maybe alcohol) you mean ? Well, protein is absolutely required, something on the order of 55 grams per day. Healthy fats are also important (avoid trans fats). As for carbs, you really don't need carbs, but inevitably get them when you eat other healthy things, like fruit and veggies. Grains (especially white flour and white rice) tend to have lots of carbs and a high glycemic index with not as many vitamins and minerals as fruits and veggies, so limit those. Alcohol isn't required, but getting a small portion of your calories from alcohol is probably OK. StuRat (talk) 16:20, 26 September 2015 (UTC)

You really don't need carbs. That's a rather controversial viewpoint. Not everyone is convinced that long-term ketosis is a good or even neutral thing for the body. --Trovatore (talk) 20:22, 26 September 2015 (UTC)

I meant you don't need to go out of your way to add carbs to your diet, as you will get all you need as a result of eating fruits and veggies. So, you don't need to add grains, potatoes and sugar to your diet in an attempt to get enough carbs. StuRat (talk) 21:45, 26 September 2015 (UTC)

What if their job requires significant physical effort and strength? ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:43, 27 September 2015 (UTC)

Sounds like you refer to carb loading. That's used by athletes to provide energy for endurance events, because they can't stop to eat during an event. However, if your job requires lots of energy and endurance, you are likely allowed to eat during the work day, to replenish your energy (even a 5 minute break can allow you to eat a piece of fruit). Thus, there's no need to carb load. StuRat (talk) 19:34, 28 September 2015 (UTC)

Exploring Europa's Ocean

I was just reading this article, NASA Shows Off The Drone That Will Explore Europa and I'm wondering isn't it dangerous to Europa's ecosystem and any life there for us to disturb it? The drone could contain an Earth virus or bacteria. Is it possible to sterilize a probe to guarantee that there's absolutely nothing living on or in it? Also, when happens to the probe? I would assume that it will eventually run out of power, fall to the bottom of the ocean and decompose. A Quest For Knowledge (talk) 14:56, 26 September 2015 (UTC)

See Interplanetary_contamination#Vulnerability_of_the_Solar_System_to_contamination and Planetary_protection for information about the procedures used to sterilize spacecraft that may enter another planet or moon. LongHairedFop (talk) 15:02, 26 September 2015 (UTC)

ALL THESE WORLDS ARE YOURS EXCEPT EUROPA. ATTEMPT NO LANDING THERE. USE THEM TOGETHER. USE THEM IN PEACE. --71.119.131.184 (talk) 18:29, 26 September 2015 (UTC)

Armadillo Relations

Hi! I was wondering if you can answer a question for me. A friend told me about an animal in the same family as an armadillo but it is supposed to be much bigger. I hope you can answer this for me.Thanks!Claire Anemone (talk) 19:32, 26 September 2015 (UTC)

Try Giant armadillo. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:39, 26 September 2015 (UTC)

THANKS!Claire Anemone (talk) 19:44, 26 September 2015 (UTC)

A giant armadillo is an armadillo. There's also the fairy armadillo, check this out. But what you really want is a Glyptodont. μηδείς (talk) 23:47, 27 September 2015 (UTC)

supermoon

Please can you tell me all the dates of supermoon eclipse events in western europe since 1990 to present day? — Preceding unsigned comment added by 42.81.42.132 (talk) 21:21, 26 September 2015 (UTC)

See Supermoon and Lunar eclipse. The only total lunar eclipse that occurred at perigee in your timeframe was the September 1997 lunar eclipse. As you may know, there's another one due on Monday, the September 2015 lunar eclipse. Tevildo (talk) 22:36, 26 September 2015 (UTC)

According to space.com, the last supermoon eclipse was in 1982, next one won't be until 2033. They are usually 18 years apart. Ssscienccce (talk) 00:10, 27 September 2015 (UTC)

Well, the 1997 eclipse was three hours away from the actual perigee - the December 1982 lunar eclipse was 10 hours away, and not visible from Europe. (The 1997 eclipse was only visible from Spain, France and Italy, but I assume that comes within the OP's definition of "Western Europe"). Presumably the space.com definition includes an implicit "visible from the USA". Monday's eclipse will be 57 minutes away, and visible from all of Europe. "Supermoon" is more of an astrological than an astronomical term, after all. Tevildo (talk) 00:40, 27 September 2015 (UTC)

That would make sense, yes. For the OP: here is a list of full moons near perigee for the 21st century. A letter after the date indicates that an eclipse occured, (a "t" stands for total eclipse). The last column gives the difference in days between nearest perigee (moment that the moon is closest) and the moment of full moon. Time is in UCT. The moment of full moon will be the moment of eclipse, based on the time you could work out if it was visible in Western Europe. One could argue that January 2001 lunar eclipse was also a supermoon eclipse (12,5 hours from epigee). The wiki page doesn't mention Europe, but given the image of the orientation of the earth during greatest eclipse, I would assume that Europe had a better view than Western Australia. Ssscienccce (talk) 15:38, 27 September 2015 (UTC)