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Wikipedia:Reference desk/Archives/Science/2014 March 12

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March 12

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Soya and manliness

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I am a male non meat eater i.e lacto-ovo-vegetarian and a fitness freak. I feel soya has almost 50% protein and very less fat and I just love it. But I heard that Soy contains large amounts of biologically active compounds called isoflavones, which function as phytoestrogens… that is, plant-based compounds that can activate estrogen receptors in the human body. Thus it can decrease my testosterone levels! Is it true ?? How much soy is optimum for daily consumption ? — Preceding unsigned comment added by 119.235.54.187 (talk) 07:54, 12 March 2014 (UTC)[reply]

We have articles on soya, isoflavones and phytoestrogens as well as gynecomastia and natural selection. --DHeyward (talk) 09:24, 12 March 2014 (UTC)[reply]
..and even manliness.--Shantavira|feed me 15:21, 12 March 2014 (UTC)[reply]
Note that estrogenic chemicals are everywhere. They may also be in milk products and in plastics and the linings of cans. As far as non-estrogenic protein sources for vegetarians; nuts, peanuts, seeds, and beans are all good, and fish and eggs are also good for those who are allowed to eat them. StuRat (talk) 21:14, 12 March 2014 (UTC)[reply]

So here in this article http://en.wikipedia.org/wiki/Phytoestrogens#Males they say that "neither soy foods nor isoflavone supplements alter measures of bioavailable testosterone concentrations in men." but it is a meta analysis study. Is it a reliable one ? — Preceding unsigned comment added by 119.235.54.187 (talk) 04:01, 13 March 2014 (UTC)[reply]

(Please don't put lots of tabs in your answers. As the Original Poster, you don't need to use any tabs at all, unless responding to an answer. I removed the excess tabs.)
I'd look at who paid for the study first, to determine if it can be trusted. Also note that high estrogenic levels would also matter, as the ratio of estrogen to testosterone is important for sexual development. StuRat (talk) 15:42, 15 March 2014 (UTC)[reply]

Epoxy resin around capacitor

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Hi all,

This might seem like a question more suited to the computing ref desk but since it's a bit science-y I thought it might get better answers here. I have capacitor in an LCD monitor that has started hissing, this is apprently quite common in LCD monitor and is due to a bad capacitor. All solutions on the internet seem to suggest either a) replace the monitor (I'd rather not), b) Turn up/down brightness (turning up makes it worse, turning it all the way down gets rid of it, but sort of defeats the point since the monitor isn't very useable.). The monitor is out of warranty and old enough that sending it for repairs might be difficult (about 8 years old - although rarely used).

I thought I could have a go at coating said capacitor in some form of non conductive heat resistant resin to keep the noise down. I figure I may as well try if the only other solution is to replace the monitor. What resin could I use? I was thinking something like the stuff they put on circuit boards to keep components from shorting and in place, it's usually brownish or black. I realise this is fairly dangerous and would take nessecary precautions and obviously not do it with the monitor plugged in. 80.254.147.164 (talk) 10:16, 12 March 2014 (UTC)[reply]

DANGER! You do not say what kind of capacitor it is. If it is an electrolytic (one marked to indicate + & - polarity), NEVER EVER enclose it in epoxy resin, and only use another type of resin if you DEFINITELY know what you are doing. The reason is that such capacitors are designed to vent when overstressed. Enclosing it in resin is the same as making any sort of pressure vessel - a circuit fault may make it explode. And a capacitor that makes any noise you can hear loud ennough to be anoyed by it is an overloaded capacitor. The hissing indicates possible arcing inside - if so failure is imminent. So coating it is resin is waste of time anyway.
To ask a question like this indicates you are not electronics trained. DO NOT work on AC voltage powered euipment unless you are qualified. Scrap the monitor or take it to a qualified repair shop.
121.215.154.87 (talk) 10:29, 12 March 2014 (UTC)[reply]
^ I can not stress how much I agree with the above statement. Do not attempt this yourself. Your fix will make it dangerous, and your lack of knowledge could kill you (no offense). Find somebody local that can do the repair for you, and simply get the capacitor replaced. The one you have is about to blow, and I mean blow.217.158.236.14 (talk) 11:22, 12 March 2014 (UTC)[reply]
OK, reading that, this was probably a stupid idea. I'll take it for repair. 80.254.147.164 (talk) 12:20, 12 March 2014 (UTC)[reply]
If the fault is confined to the capacitor, and you can find an old-fashioned TV repair shop, then the cost might be quite small. The modern repair process is to send the equipment away to a specialist central repair shop and the cost of transport and administration usually exceeds the cost of repair. Dbfirs 17:48, 12 March 2014 (UTC)[reply]

Cosmos - Moon formation up to date?

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Is Cosmos: A Spacetime Odyssey up to date about the formation of the Moon (in the first episode)? It talks about the Moon forming from "fragments of orbiting debris", which doesn't seem the same as the modern impact by a Mars-sized body. Bubba73 You talkin' to me? 19:10, 12 March 2014 (UTC)[reply]

It formed by impact with a Mars-sized body, which ejected fragments of debris into orbit, which coalesced into the Moon. See giant impact hypothesis. --Bowlhover (talk) 19:34, 12 March 2014 (UTC)[reply]
He didn't really mention the giant impact. Bubba73 You talkin' to me? 20:46, 12 March 2014 (UTC)[reply]
Yea, I noticed that, too. My guess is that he's playing it safe, by allowing for either the giant impact hypothesis or the Moon just coalescing from smaller objects. StuRat (talk) 21:18, 12 March 2014 (UTC)[reply]
Or, it's the first episode and they'll get into greater detail later. There's 13 episodes, and they've broadcast 1. --Jayron32 22:44, 12 March 2014 (UTC)[reply]
The script for the first episode sounded a lot like the script for Sagan's first episode. It would be interesting to run the shows side by side and see where they differ. For example, in the new series the animations of the historic figures looked like they were done by the guys who created Clutch Cargo. ←Baseball Bugs What's up, Doc? carrots23:00, 12 March 2014 (UTC)[reply]
What did Carl Sagan have to say about the Moon's formation ? If he didn't agree with the giant impact hypothesis, perhaps Neil doesn't want to contradict him. StuRat (talk) 00:28, 13 March 2014 (UTC)[reply]
We don't know what this series is going to say about the moon yet because it's only 7.7% complete. --Jayron32 00:37, 13 March 2014 (UTC)[reply]
I don't remember what Sagan said in the 1980 version, but the great impact hypothesis might not have been the dominant theory at the time, whereas today I think it is. Bubba73 You talkin' to me? 02:19, 13 March 2014 (UTC)[reply]
Of note, regarding the animation, is that Seth MacFarlane is an executive producer of the series and provided much of the financial backing and business connections to get it made. He provided the voice for Giordano Bruno himself and probably had a lot to do with the animation and creative decisions thereof. --Jayron32 23:08, 12 March 2014 (UTC)[reply]
Yes, many of the words were the same as I remember from the original show. Bubba73 You talkin' to me? 00:26, 13 March 2014 (UTC)[reply]
  • The glancing impact hypothesis didn't gain much currency until at earliest the '90's (our article says Theia was hypothesized in 2000) and was based on computer simulations that solved for the right size bodies and angular momentum with a glancing blow by a Mars-sized object. It's widely accepted now, I see no reason for the remake to avoid it. μηδείς (talk) 21:00, 14 March 2014 (UTC)[reply]
That is what I thought. Maybe it will come up later. Bubba73 You talkin' to me? 23:32, 14 March 2014 (UTC)[reply]
It was mentioned in the episode, but only briefly. IIRC they talked about the big impact, talked some more about the Earth's surface, then talked about the moon forming from debris. So, it wasn't tied together neatly. — The Hand That Feeds You:Bite 20:06, 16 March 2014 (UTC)[reply]

Single reel or double reel cassette tape

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What is the advantage of the former? You always have to rewind it completely to use it again. Although a double reel would need a bigger cartridge, the cartridge is the cheap part of the cassette tape. That would still be an issue in the case of big reels (like movies in 35-millimeter film), but why do Linear Tape-Open, for example, was designed with just one? That's contrary to VHS, Betamax, and audio cassettes. OsmanRF34 (talk) 22:47, 12 March 2014 (UTC)[reply]

(For those unfamiliar with this topic, the single reel system uses a take-up reel on the player.) The issue probably is size, but not because a larger cassette is more expensive, but rather because it's less portable. StuRat (talk) 00:24, 13 March 2014 (UTC)[reply]
StuRat has correctly demonstrated the English language contraction "it's" which means "it is". 84.209.89.214 (talk) 12:04, 14 March 2014 (UTC)[reply]
Storage Density. 70.174.141.142 (talk) 00:45, 13 March 2014 (UTC)[reply]

Banded Iron Formations

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Hello, what are the most important controversies surrounding the banded iron formations in the geological community? — Preceding unsigned comment added by 149.152.23.34 (talk) 23:34, 12 March 2014 (UTC)[reply]

Please do your own homework.
Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. --Jayron32 23:45, 12 March 2014 (UTC)[reply]

Its not a homework question. — Preceding unsigned comment added by 149.152.23.34 (talk) 23:59, 12 March 2014 (UTC)[reply]

In that case there seems to be something missing. You seem to have knowledge that there are controversies regarding this topic. Please tell us why you think that there are. StuRat (talk) 00:14, 13 March 2014 (UTC)[reply]
Snowball. 70.174.141.142 (talk) 00:17, 13 March 2014 (UTC)[reply]
I've taken the liberty of wikilinking the term in the original question. Sometimes when you do that, you find your question answers itself, but in this case it's not clear that the article is sufficient. Wnt (talk) 03:00, 13 March 2014 (UTC)[reply]