Wikipedia:Reference desk/Archives/Science/2017 April 8

= April 8 =

Am I right-handed or left-handed?
I don't know whether I am left-handed or right-handed. When I was a child, I began writing with my left hand and then, when I was a teenager, I trained my right hand to write. Also as a child, I played piano for 2 years; and now, I play piano intermittently for about a year. The piano trained me to use both hands. I can use a right-handed can opener and right-handed scissors easily. When I cut food, I find that cutting with my right hand is much more easier than with my left hand. When I ride my bicycle, I can lift my right hand while my left hand holds the handle, but when I switch hands, I find it very hard to lift my left hand. Am I right-handed or left-handed? Or is handedness a spectrum? 50.4.236.254 (talk) 01:21, 8 April 2017 (UTC)
 * According to the handedness: "There are four types of handedness: left-handedness, right-handedness, mixed-handedness, and ambidexterity." I'd bet you're the 3rd one. --Hofhof (talk) 01:26, 8 April 2017 (UTC)
 * Brooks Robinson batted and threw right-handed, but signed autographs left-handed. ←Baseball Bugs What's up, Doc? carrots→ 01:42, 8 April 2017 (UTC)
 * Did you know Hideki Matsui batted left for the Yankees cause he beat the local kids so bad they made him bat from the wrong side? Sagittarian Milky Way (talk) 17:11, 8 April 2017 (UTC)
 * Interesting story. A lot of great hitters taught themselves to bat lefthanded on the theory that it puts them a step or two closer to first base, along with the natural tendency of a righthanded pitcher to bring the ball more to their favor. ←Baseball Bugs What's up, Doc? carrots→ 03:20, 9 April 2017 (UTC)
 * I'm righty batting left; to me it feels natural to pull with the stronger arm. (The fact that my left eye is better for distance could also have something to do with it.) --Trovatore (talk) 01:48, 10 April 2017 (UTC)
 * That can figure into it too. It's kind of analogous to a backhand shot in tennis. ←Baseball Bugs What's up, Doc? carrots→ 03:28, 10 April 2017 (UTC)
 * I feel the same as Trotavore. I golf left-handed too. shoy (reactions) 18:23, 10 April 2017 (UTC)
 * Trota -vore. That's kinda good, actually. --Trovatore (talk) 20:33, 10 April 2017 (UTC)
 * It is a spectrum - most people can use both hands for at least some things, and it is perfectly possible to learn to use the less dominant hand (if you lose one, you have no alternative but to learn). However, if your first instinct as a child was to use the left hand, then that is probably the dominant one. Wymspen (talk) 09:36, 8 April 2017 (UTC)
 * Did anyone else flash on Guys and Dolls at the title of this question? --Trovatore (talk) 09:47, 8 April 2017 (UTC)
 * For those of us unfamiliar with that story, could you elaborate? ←Baseball Bugs What's up, Doc? carrots→ 03:17, 9 April 2017 (UTC)
 * It's a line from the movie (not sure about the play). Thug asks another thug, "Am I right or left handed?", thug 2 responds "How would I know?", Thug1 says "I'll give you a clue." and pounds him in the face with one hand or the other. - Nunh-huh 05:06, 9 April 2017 (UTC)
 * Sky Masterson decks Big Jule. But I don't think a gentleman would refer to Sky Masterson as a "thug". Big Jule, yes. --jpgordon&#x1d122;&#x1d106; &#x1D110;&#x1d107; 14:38, 9 April 2017 (UTC)
 * Thug is as thug does. But I'm no gentleman :) - Nunh-huh 14:48, 9 April 2017 (UTC)
 * Sky was not a thug, he insists, stamping his little feet. --jpgordon&#x1d122;&#x1d106; &#x1D110;&#x1d107; 23:51, 9 April 2017 (UTC)
 * Yeah, Jerry Orbach didn't think so either. He too was wrong. :) - Nunh-huh 04:52, 10 April 2017 (UTC)
 * In that scene, Masterson used violence in the proper defense of another. It was the only instance (that I recall at least) of him using violence in the entire film, and I do not think any off-screen incident was even alluded to.  He was a gambler, not a thug. --Trovatore (talk) 04:57, 10 April 2017 (UTC)
 * In that scene, Masterson used violence in the proper defense of another. It was the only instance (that I recall at least) of him using violence in the entire film, and I do not think any off-screen incident was even alluded to.  He was a gambler, not a thug. --Trovatore (talk) 04:57, 10 April 2017 (UTC)

Nutrient-dense food with high risk of bacterial and parasite infection vs. nutrient-scarce food with high risk of chronic illnesses
I always wonder what kind of metric people use to assess whether something is "healthy". It seems that, whatever you eat, there are people who say there are bad things in everything. So, it's damn if you do and damn if you don't. Hamburgers, French fries, and soda pop are portrayed as "unhealthy". But no one seems to be concerned with eating an apple or red lettuce leaf straight from the store or pick-your-own-vegetable farm. I wonder what would happen if a person just doesn't care about health and buys fruits and vegetables from the grocery store and eats them completely uncooked and unwashed for the sake of time-saving convenience. Never mind the taste of it. I know many vegetables taste bitter, but if a person is hungry, he doesn't care and would eat the bitter vegetables raw. Or he can eat the sweet fruits. And nuts and seeds and avocados. And tofu is eaten straight from the container, because tofu is cooked by the manufacturer. I am not sure which is worse - eating nutrient-dense food straight from the grocery store or pick-your-own-produce farm (after purchase, of course) with possible risk of catching an acute illness and pesticide poisoning or eating nutrient-scarce, energy-dense food with excessive sodium and excessive amount of highly absorbable sugars with possible risk of developing a chronic illness. Plus, people in a poor country may drink water and catch a parasitic infection or boil water to kill parasites, and even though people in a rich country can drink chlorinated tap water for free, they choose not to and drink some kind of sweet beverage instead, and each beverage is labelled with health claims, like "vitamin C" or "caffeine" or "B vitamins". Do people really know what is "healthy"? Or is everyone making stuff up and basing their opinions on correlations? 50.4.236.254 (talk) 03:43, 8 April 2017 (UTC)


 * You can look at what indigenous people eat and how well they do on various aspects of health compared to us, see e.g. here. Typical results are that they are more prone to infections, but they get a lot less heart disease and strokes. So, it seems to me that all we need to do is eat more vegetables, eat less meat and use less cooking oil (replace refined oils by walnuts and chia seeds). Count Iblis (talk) 08:22, 8 April 2017 (UTC)


 * You have to accept a risk. No food is without some risk, but no food at all is invariably fatal. Wymspen (talk) 11:17, 8 April 2017 (UTC)
 * Dying is the ultimate time-saver, at least for the deceased. ←Baseball Bugs What's up, Doc? carrots→ 03:16, 9 April 2017 (UTC)


 * There are certainly scientific assessments of what people need to eat to stay healthy long-term - see healthy diet. Yes, the risk of foodborne illness is determined by the type of food (for example milk can incubate dangerous microorganisms much more easily than a banana, which is why it is pasteurized) but also by the conditions and practices at the source (is animal excrement allowed to touch the lettuce? are toxic pesticides used or is it organic?) and food preparation, handling, and refrigeration. There are some limitations to nutrition science (it is difficult to do ethical experiments on people that might injure them, and humans and our diets are very complicated and generally not limited to the lab environment) and to anyone's ability to assess the safety practices of any particular food supplier.  If you want to know if it's better to eat a hamburger or an unwashed apple, there are dozens of factors to multiply in each case, and it's very specific to the supplier, so there's no general answer I can give you, but it's a question that's possible to answer with more than just made-up opinions.  I think people who follow scientifically grounded advice on diet and food safety really can "eat healthy" in both senses.  It is very true that a lot of everyday people don't follow this advice, in many cases due to ignorance and in many cases in the short term it makes them unhappy not to eat what they desire.  A lot of food marketing these days does make incorrect or misleading health claims grounded in sales not science; it's possible stronger government regulation could fix that. -- Beland (talk) 09:38, 9 April 2017 (UTC)
 * "are toxic pesticides used or is it organic?" is a false dichotomy Nil Einne (talk) 10:43, 9 April 2017 (UTC)
 * It was a good point as if it was organic, it is likely to have made contact with animal excrement. Graeme Bartlett (talk) 14:00, 9 April 2017 (UTC)
 * Depends on what one means by organic. To a chemist it means something entirely different than it does to a marketing professional.  -- Jayron 32 15:27, 10 April 2017 (UTC)

Why was azeotropic isopropanol not sold in stores in the past?
Only 70%? (your location may be different) Now they even sell 50% for the cheapskate, lol. Sagittarian Milky Way (talk) 16:10, 8 April 2017 (UTC)


 * Sold for what purposes ? As a disinfectant ? StuRat (talk) 16:17, 8 April 2017 (UTC)


 * Yes. Sagittarian Milky Way (talk) 16:35, 8 April 2017 (UTC)
 * It likely has to do with antimicrobial/disinfectant activity, which does change depending on the concentration. 70% has been shown to be quite effective. See CDC. --OuroborosCobra (talk) 16:57, 8 April 2017 (UTC)