Wikipedia:Reference desk/Archives/Science/2012 September 23

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September 23

Guitar strings: tuning and tension

I'm fairly certain that this is more of a science question than an entertainment or humanities one, but if not then feel free to move it. Essentially, I am looking for a table giving the total force of the tension (preferably in lbf) exerted by a guitar string of a given gauge and composition when tuned to pitch. For reasons that are entirely too complicated for me to spell out here, I need to compare the tension of low-gauge (.008-.038 or so) nickel-wound electric guitar strings with the equivalent tuning on a set of classical guitar nylon strings. Thanks in advance. Evanh2008 ^{(talk|contribs)} 02:37, 23 September 2012 (UTC)

If you type "Guitar string tension" into Google, you get a shitton of references. I mean, like more than I feel like linking. There's even some where you enter the guage and the desired note in a little calculator ap, and it returns the tension for you. --Jayron32 02:50, 23 September 2012 (UTC)

I guess I should have noted that I did a Google search before posting here, and "shitton" would be a good way of describing the number of results, except none of them seem to care much about nylon strings, which is the info I'm after. The tension needed to acquire a given note increases proportionately along with the weight of the string, so the force (in newtons, lbf, or however else you measure it) is going to increase as well. Evanh2008 ^{(talk|contribs)} 04:08, 23 September 2012 (UTC)

Ah, sorry. Yeah, most of the information seems to be for metal strings. Lemme take another look. --Jayron32 04:24, 23 September 2012 (UTC)

Yeah, the very first link on that google search I recommended is this page From D'Addario. The very first link on THAT page is this manual that has full tension information for every string D'Addario makes, including both metal and nylon strings. I know it is only one manufacturer, but there's enough different types of strings and guages and types to give you some general trends. --Jayron32 04:28, 23 September 2012 (UTC)

That's exactly what I needed! I guess I should have looked closer. Thanks! Evanh2008 ^{(talk|contribs)} 04:48, 23 September 2012 (UTC)

Line of lakes in North America

this map

On the counter in our office is an outdated map showing all the weather stations in Canada and the US. Earlier today a pilot mentioned that they had not noticed the way several large lakes seemed to form a line. After he left I went to look and he appears to be correct. If you look at the map on the right you can see what I mean. From north to south there is Great Bear Lake, Great Slave Lake, Lake Athabasca, Reindeer Lake, Lake Winnipeg (along with Cedar Lake (Manitoba), Lake Winnipegosis and Lake Manitoba), Lake of the Woods, Rainy Lake and the Great Lakes. The pilots question, and mine, is if there is any reason why the lakes would have formed in what appears to be a line like that? CambridgeBayWeather (talk) 03:18, 23 September 2012 (UTC)

You won't believe this, but only 2 or 3 days ago I noticed that, also for the first time. I too wondered what would have caused it. I can't even remember now why I was looking at a map of such a godforsaken place as North America in the first place. :) -- ♬ Jack of Oz ♬ ^{[your turn]} 03:26, 23 September 2012 (UTC)

Because you looking up the activities of Australians in Cambridge Bay. CambridgeBayWeather (talk) 17:38, 23 September 2012 (UTC)

(edit conflict)Yes, there is. Those lakes mark the edge of a very hard chunk of crustal rock known as the Canadian Shield. The lakes all lie just outside the western edge of the Canadian Shield. The other margins of the shield are the Great Lakes and the St. Lawrence River. Presumably, that line of lakes marks where softer rock was more easily carved by glacial action than the harder Canadian Shield, which is why the lakes formed where they did. --Jayron32 03:26, 23 September 2012 (UTC)

(ec)They are all remnant glacial lakes left from the retreating Laurentide Ice Sheet, and perhaps other ice sheets; [1]. I think the ice sheet(s) grew from and retreated back to its core over what's now Hudson Bay. The Great Lakes formed where they did because the ice sheet repeatedly grew and shrank back and forth over that area, creating morraines, meltwater lakes, scouring out basins, etc. I suspect the same is true for the line of lakes extending northwest in Canada. Pfly (talk) 03:30, 23 September 2012 (UTC)

See also Lake Agassiz, the ice age precursor to Lake Winnipeg and nearby lakes. Pfly (talk) 03:32, 23 September 2012 (UTC)

You guys are spoilsports. I was imagining an incoming comet, which skipped across the land like a pebble across a lake, doing major damage along the way, before proceeding out into the Atlantic Ocean where it scored a direct hit on Atlantis. -- ♬ Jack of Oz ♬ ^{[your turn]} 03:33, 23 September 2012 (UTC)

Heh, well I find the notion of ice sheets over a mile thick crushing the land and forming large lakes and ice dams, which repeatedly burst and create enormous catastrophic floods that carve deep canyons and leave gigantic ripple marks fairly impressive. Pfly (talk) 03:37, 23 September 2012 (UTC)

Took me a few minutes to find it, but the Great Bear, Great Slave, and Athabaska Lakes were once a single proglacial lake known as Lake McConnell, a northern version of Lake Agassiz. I'm kind of surprised we don't have a page about it, even a stub.[I love how saying something like that on the ref desk can result in a redlink turning blue, thanks Clarityfiend!] There's lots of technical detail in this paper, [2], about the formation of lakes in central-north North America during the last glacial period. Pfly (talk) 03:50, 23 September 2012 (UTC)

It was 2-for-1 Saturday, so you also got, for no extra charge (shipping and handling extra), McConnell Lake. Clarityfiend (talk) 00:22, 24 September 2012 (UTC)

One more bit (I've been reading about the formation of the Great Lakes as the ice retreated for use over at Lake Michigan-Huron, so can't help but look up a bit about the more northern lakes now), there's a nice map of glacial Lake Agassiz and McConnell, Lake Superior etc, and the retreating ice sheet, overlain on the present-day lakes, here, [3]. Pfly (talk) 03:59, 23 September 2012 (UTC)

• Glacial megalakes? ...scablands. μηδείς (talk) 04:48, 23 September 2012 (UTC)

Thanks everybody. I assume that the two lakes in Quebec and the on in Labrador were also formed the same way but on the other side of the shield. CambridgeBayWeather (talk) 17:38, 23 September 2012 (UTC)

I think those are reservoirs, from west to east Robert-Bourassa Reservoir on La Grande River, Caniapiscau Reservoir, and Smallwood Reservoir, I think. But there are definitely a lot of glacial lakes in the region, and some of those reservoirs incorporated pre-existing glacial lakes, from what I can tell. Not all of Quebec's large lakes are glacial—Manicouagan Reservoir was created by an asteroid impact, which should make Jack of Oz happy! Pfly (talk) 20:03, 23 September 2012 (UTC)

Thanks for keeping me in mind. -- ♬ Jack of Oz ♬ ^{[your turn]} 19:40, 24 September 2012 (UTC)

Never thought of that. By the way did you know that what the most important point of Manicouagan Reservoir was at one time. CambridgeBayWeather (talk) 21:49, 23 September 2012 (UTC)

has crab nebula rotation round any center?

Crab nebula is the remnant of any super nova exploded about 1000 years ago. The central pulsar is rotating hardly fast. The question is about cloud which is continually expanding.Does this cloud rotating round any center? I want to know this for finding the effect of global system on same nebula. in fact my main aim of this question is : finding inertial momentum of such nebula ,and generalizing it for further researches. kindly replay please ...... thanks--Akbarmohammadzade (talk) 07:31, 23 September 2012 (UTC)

I should provide a link to Crab Nebula, so everyone can look there. It says that the central star, the Crab Pulsar "...is believed to be about 28–30 km in diameter; it emits pulses of radiation every 33 milliseconds". So, it's rapidly rotating. This suggests to me that the entire system is likely to have some rotation, too. StuRat (talk) 08:35, 23 September 2012 (UTC)

By conservation of angular momentum, the cloud should have transversal speed that is at about the same order of magnitude as the rotation speed at the pulsars surface. The pulsars equator rotates at ~1000-1500km/s. This is comparable to the radial expansion speed of the nebula, so not insignificant. On the other hand, it means that the outer parts of the nebula would complete a full rotation once in ~10000 years or so. --Stephan Schulz (talk) 09:35, 23 September 2012 (UTC)

The total angular momentum of a system stays the same, but that doesn't imply the parts themselves rotate. Without gravity, everything would move in straight lines, but angular momentum of the system would still be conserved. Any rotation around the centre must fit Newtons law of motion for the gravitational force. I could be wrong, but Kepler's third law seems to suggest a period in the order of 10⁷ years for the outer part (distance of 5ly), if it was in circular orbit around the pulsar. Ssscienccce (talk) 11:26, 23 September 2012 (UTC)

Sorry if I was obtuse. No, I don't think any of the gas is in a stable orbit around the pulsar. It does have, however, a rotational component. It would do that even if, at the moment of the explosion, gravity would be magically turned of. The surface of the star would keep its existing speed (originally tangential to the star's surface) and get an additional radial component from the explosion. Ignoring friction and interaction with the interstellar medium, the rotational component would remain the same, and as the gas moves out, the angular speed goes down to keep the angular momentum the same. --Stephan Schulz (talk) 11:39, 23 September 2012 (UTC)

It is in my mind for some years to find analytical mechanics calculation for such system when the expanding comes to an end: 1-outer part is a cloud (gas or plasma system) 2- the inner core is very dense and rotating . 3- core object has gravity field. 4- can system condense again?and so on.....--Akbarmohammadzade (talk) 09:07, 23 September 2012 (UTC)

You want to take a look at escape velocity. Those parts of the cloud that move faster than the escape velocity (at that radius) will escape. The mass to take into account is (to a first approximation) the mass of the pulsar and the nebula up to the radius you consider (see shell theorem). Escape velocity grows with the square of the central mass. Escape velocity from our sun at the orbit of mercury is ~67 km/s. So even assuming the Crab nebula has 10 solar masses, it is certain that most of the gas in the nebula will escape, i.e. it will nor re-condense, even if we only take the radial velocity into account. --Stephan Schulz (talk) 09:45, 23 September 2012 (UTC)

Schulz first two posts to this thread are incorrect. The third one - about scape velocity - is fine. The tangential component of the velocity is NOT conserved. The angular momentum is conserved. Take for instance the simple example of a point particle with angular momentum L = mv_tr where the mass m doesn't change. If L is conserved and the radius r is increasing, than the tangential component of the velocity v_t must decrease becoming negligible over time. Right now it is already negligible. Dauto (talk) 14:55, 23 September 2012 (UTC)

Oi. Yes, you're right - the speed remains the same, but the direction becomes increasingly non-tangential. At 5 lightyears out, it should be nearly negligible. Sorry. --Stephan Schulz (talk) 15:03, 23 September 2012 (UTC)

Coprolalia

Why would certain disorders include the involuntary and out of context use of obscene words or socially inappropriate and derogatory remarks (coprolalia)? (At Tourette syndrome I learned that coprolalia is present in only a small minority of people with Tourette's.) And at Coprolalia I learn that "Coprolalia encompasses words and phrases that are culturally taboo or generally unsuitable for acceptable social use, when used out of context." My question, or at least that which I'm curious about, is the sort of connection there might be between what is considered a medical disorder, and how this interfaces with cultural norms. I am almost tempted to consider that the cultural norms, at least in part, cause the medical disorder. But I really know little about this. It strikes me as odd that those words that are considered socially inappropriate should be the symptom of a disease. What is so special about foul language that it seemingly characterizes a number of medical conditions? I find this paragraph:

"Coprolalia is not unique to tic disorders; it is also a rare symptom of other neurological disorders. It may occur after injuries to the brain such as stroke and encephalitis; in other neurological conditions such as choreoacanthocytosis, seizures, and Lesch-Nyhan syndrome; and rarely in persons with dementia or obsessive–compulsive disorder in the absence of tics."[4]

These conditions I would think have a biological basis. What is the connection between malfunctioning biology and the use of socially unacceptable words? My apologies if my question may be a little malformed too. I don't have a background in science or medicine. Bus stop (talk) 13:13, 23 September 2012 (UTC)

Tourette's is not easily understood, and I don't understand it. My impression from various documentaries is that Tourette's patients can do anything from simple eye blinking to having to get up and run to having to knock on a window three times. From [5] it sounds like some authorities prefer to segregate "mental tics" as a comorbid case of obsessive-compulsive disorder. As a result, verbal tics remain which are simple or complex, and include things like repeating oneself or others or saying a particular phrase over and over. Something about this dividing line between "tic" and "compulsion" seems dubious to me, but I'm in no position to be outwitting the experts here. Wnt (talk) 14:18, 23 September 2012 (UTC)

• Unfortunately this is a prime example of the sort of condition that is difficult to investigate, because by its nature it can only be studied in humans, not in animals where it is possible to record brain activity. The basic story seems to be that cursing and other types of "formulaic speech" are at partly handled by different brain systems than normal speech. There is quite a bit of evidence to support that idea, such as numerous cases of people with aphasia (impairment of normal speech) who are still able to show coprolalia. Unfortunately there is very little information to pin down the location of the systems that support formulaic speech, other than some indication that they involve the right hemisphere more than normal speech does. Looie496 (talk) 16:32, 23 September 2012 (UTC)

I didn't know what "formulaic speech" was. Would a string of expletives be a special form of "formulaic speech"? Would a string of expletives be in some way quintessential "formulaic speech"? I find references to "formulaic speech" here, here, and here. But in those sources I see no specific reference to socially unacceptable language. Bus stop (talk) 17:48, 23 September 2012 (UTC)

I think it is talking about the intersection of compulsive behavior and speaking: Various "lalias" are generally disorders that involve meaningless or automatic speech; i.e. speech which is divorced from conscious control. For example Echolalia is the automatic and unconsious compulsion to repeat what someone else says. It isn't under the conscious control of the speaker, so it is a compulsive behavior. Coprolalia is the automatic and unconsious compulsion to use profanities. --Jayron32 18:15, 23 September 2012 (UTC)

This paper is specifically what I was thinking of. Looie496 (talk) 18:29, 23 September 2012 (UTC)

What would be the relationship if any between coprolalia, copropraxia, and coprographia? One might say that they all involve some form of obscenity and so they are related. All three have in common that they are involuntary expressions by a person considered to have some kind of a medical problem. I can understand that coprolalia may be an example of "formulaic speech". But are copropraxia and coprographia somehow "formulaic" expressions too? Are the three related in any way? Bus stop (talk) 19:55, 24 September 2012 (UTC)

Discovery of the God particle.

What led to the discovery of the Higgs Boson and how is it dicovered? — Preceding unsigned comment added by Saikatdb05 (talk • contribs) 16:07, 23 September 2012 (UTC)

Please read our article on the Higgs boson. Looie496 (talk) 16:33, 23 September 2012 (UTC)

And can we stop calling it the God particle? HiLo48 (talk) 23:36, 23 September 2012 (UTC)

It irritates me, too, but a prominent physicist coined the term, and many have used it! Any reliable source stating that the consensus is clearly against the term's use? -- Scray (talk) 00:24, 24 September 2012 (UTC)

here, to some extent. Bubba73 ^{You talkin' to me?} 04:06, 24 September 2012 (UTC)

Does this count as a reliable source? Deor (talk) 11:42, 24 September 2012 (UTC)

See here: "Higgs is an atheist, and is displeased that the Higgs particle is nicknamed the "God particle",[36] as he believes the term "might offend people who are religious".[37] Usually this nickname for the Higgs boson is attributed to Leon Lederman, the author of the book The God Particle: If the Universe Is the Answer, What Is the Question?, but the name is the result of the insistence of Lederman's publisher: Lederman had originally intended to refer to it as the "goddamn particle".[38]" Count Iblis (talk) 18:01, 24 September 2012 (UTC)

Well, I've been told my people who should know that God is quite pleased with His particle. He's even autographed a few of them. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:12, 25 September 2012 (UTC)

Sorry for this is science reference desk, but that (Lederman had originally intended to refer to it as the "goddamn particle".) said, believing god's goodness, as logic goes, ...if god destines us disastrous..., how do you think? (I am not sure if I'm following, though.)

Like sushi (talk) 21:55, 26 September 2012 (UTC)

Legs > 4

What non-insect, non-arachnid animal species other than all varieties of octopus, squid, and crab have more than four legs? 67.163.109.173 (talk) 18:19, 23 September 2012 (UTC)

There are all kinds of them, but I hate the idea of the Ref desks being used for quiz questions. Looie496 (talk) 18:27, 23 September 2012 (UTC)

Assuming good faith; have a look at our article on Arthropods and factor out insects, spiders and crabs from the list. Also, some Cephalopods (but don't forget to discount octopus and squid) and some Cnidarias, but only if you are counting tentacles as legs. Alansplodge (talk) 18:37, 23 September 2012 (UTC)

This is the sort of thing that is typically best done by exhaustive search. If you look at the animal article, you can look at the taxobox at the side and see what types of subgroups there are. Just go through them (possibly drilling down further into each one until you get a clear picture of what the group is like) and figure out if any of them meet your criteria. For example, you should quickly realize that Porifera and Placozoa don't have any legs, Chordata either have no legs or four legs, etc. Aside from the aforementioned examples located under Arthropoda and Mollusca, other places to look are Annelida (if parapodia count as legs), Tardigrada, Lobopodia, Echinodermata, etc. - and that's a brief glance through. More diligent searching will likely be rewarded by further examples. -- 71.35.101.136 (talk) 18:50, 23 September 2012 (UTC)

See our article on Sleipnir. --Cookatoo.ergo.ZooM (talk) 19:36, 23 September 2012 (UTC)

From the first series of Blackadder "Strange portents have been seen; a horse with eight legs and two heads" "Maybe that's two horses standing next to each other?" "Oh..." Alansplodge (talk) 01:45, 25 September 2012 (UTC)

Cows. If you stick 'cow five legs' into Google you'll find lots of pictures of cows wth five legs. Dmcq (talk) 17:44, 24 September 2012 (UTC)

linking is not so hard to do. μηδείς (talk) 21:23, 24 September 2012 (UTC)

Did I miss centipedes or millipedes being mentioned or ruled out by the exclusions listed in the question? --NorwegianBlue ^talk 20:24, 25 September 2012 (UTC)

Oops, yes. They're arthropods. But an obvious answer if it indeed is a quiz question. --NorwegianBlue ^talk 20:25, 25 September 2012 (UTC)

Pitch Rising?

Why does the pitch of the bell on my mountain bike rise by about half a semi-tone as it fades?--Gilderien Chat|List of good deeds 18:40, 23 September 2012 (UTC)

I can think of several possibilities but does it sound tonaly pure? And is it high if you ring it gently? --BozMo talk 21:02, 23 September 2012 (UTC)

It sounds like more than one mode is excited in the bell when you ring it, and the lower-frequency mode has higher damping and therefore fades away quicker. Presumably when you ring the bell the lower-frequency mode is more strongly excited, so its sound covers that of the higher-frequency mode initially.--Srleffler (talk) 01:51, 24 September 2012 (UTC)

For an illustration of multiple modes see the cantilever animations in: Vibration: Illustration of a multiple DOF problem. You'll have to click the images twice (once to go to file page, second time to see full resolution) to see the animated versions. Different modes aren't the only cause of multiple frequenties, each mode will have a ground frequency and it's harmonics. (The thickness of the material will cause deviation from the true harmonic frequency. The amplitude can also cause distortion.)

One problem with the theory of quicker fading of lower frequencies is that usually the opposite happens: the high frequencies decay quicker than the low ones (see for example An experimental study of acoustical properties of tubular tower bells). But maybe in this particular case some factor changes that, for example the point where the bell is attached may provide more damping in some modes than other, due to it being either an intermediate or a fixed end node.

Alternatively, it could be a perceived rather than an actual difference in frequency. pitch is not the same as frequency, when for example several harmonics are present, the resulting pitch can be that of the missing fundamental, i.e. a frequency that isn't there. Pitch is dependent on volume: quote from the article: "The pitch of lower tones gets lower as sound pressure increases. For instance, a tone of 200 Hz that is very loud will seem to be one semitone lower in pitch than if it is just barely audible."

Probably related to this is the fact that sensitivity to low frequencies drops faster than for high frequencies. See Equal-loudness contour where 1000 Hz at 20 dB SPL and at 80 dB SPL is as loud as 20Hz at respectively 90 and 120 dB SPL; the difference dropping from 70 to 40 at higher volume. see also A-weighting, where the A curve was originally meant for low volume loudness measurement. Ssscienccce (talk) 00:19, 25 September 2012 (UTC)

I think your statement that each mode will have a ground frequency and harmonics is wrong. Rather, each mode has a single frequency; each harmonic present corresponds to one mode of the system.--Srleffler (talk) 16:24, 26 September 2012 (UTC)

You're right, where I talked about different modes I should have said mode shapes or degrees of freedom. Terminology is not my strongest point. Ssscienccce (talk) 15:30, 27 September 2012 (UTC)

Banana storage

I just bought some bananas which came in a sealed plastic bag (no holes). Usually you want to take fruit out of plastic bags, as the ethylene and moisture trapped inside can make them rot faster. However, bananas can't be refrigerated, and the plastic bag will keep the fruit flies away. So, should they be stored that way ? StuRat (talk) 19:06, 23 September 2012 (UTC)

Bananas can be refrigerated. However, the skin turns black. This does not matter as you don't eat the skin. For the same reason I'm not too concerned about fruit flies either. --TammyMoet (talk) 19:28, 23 September 2012 (UTC)

I agree--bananas can be refrigerated--I do so, and I think it makes them last longer. I also think it makes them taste better, though my wife disagrees. I'm pretty sure I read in the book Banana: The Fate of the Fruit that Changed the World that the don't-refrigerate rule was propaganda put out by the producers (to make people's bananas go bad faster so they'd need to stock up sooner). Duoduoduo (talk) 20:07, 23 September 2012 (UTC)

I used to grow bananas in the garden in Cote d'Ivoire but the drawback was getting 250 ripening at once (one flower= 250 bananas). Fridge was no good as they went black and mouldy. When visiting Societe de Cultivation de Bananes I was told that bananas have a critical temperature of about 17C. Above 17C they will ripen and then go off, below 17C without light they keep for a long time without ageing much provided they are not too cold. They had storage containers at a bit less than 17C. So I suggest you try a wine cellar rather than a fridge. The 17C think could have been hogwash for visitors of course but SCB were pretty serious (they picked bananas onto moving wires between rows to avoid bruising the back of bunches). And 17C is hard to attain in West Africa. But worth a try at say 10C in the dark. --BozMo talk 20:54, 23 September 2012 (UTC)

I don't have a wine cellar, but might try leaving them on the back (enclosed) porch. This time of year, the temps are around those. StuRat (talk) 21:39, 23 September 2012 (UTC)

Lay out banana slices on wax paper and freeze them (so they don't stick together), then store them in an airtight container so they don't get frostbit and they make great snacks and smoothie ingredients. μηδείς (talk) 22:04, 23 September 2012 (UTC)

Sounds yummy. StuRat (talk) 04:34, 24 September 2012 (UTC)

They will eventually brown if not well sealed, but since they are frozen, moderate browning doesn't effect one's enjoyment. μηδείς (talk) 16:42, 24 September 2012 (UTC)

Interestingly, there was a pyramid craze (this needs an article!) back in the '70's, at which time it was suggested that fruit placed under a pyramid would not so quickly rot. My second-grade teacher asked me to make her a few pyramidal shells from folded paper, which was something I had been doing out of sheer boredom in class. They didn't stop the bananas from browning, unfortunately. μηδείς (talk) 21:20, 24 September 2012 (UTC)

Term was Pyramid Power - apparently two rival authors tried to fight for ownership of the title. Wnt (talk) 23:20, 24 September 2012 (UTC)

And were they sold as part of a pyramid scheme ? :-) StuRat (talk) 00:53, 25 September 2012 (UTC)

Chicken broth

I like to buy rotisserie chicken, but take the skin off before I eat it (because it's high in cholesterol). Rather than waste the skin, I like to use it, along with the bones, to make broth. I still don't eat the skin, but find that boiling the skin and bones makes a nice base for a soup. My question is, does the bad cholesterol from the skin find it's way into the broth or stay in the skin, when the skin is boiled ? StuRat (talk) 19:36, 23 September 2012 (UTC)

It does go into the broth. However, as far as I know, there now a fairly strong consensus that food cholesterol has only a very minor effect on serum cholesterol. General overeating and a high-fat diet are more likely causes of bad lipid profiles and high LDL cholesterol. --Stephan Schulz (talk) 19:46, 23 September 2012 (UTC)

Thanks. Does 100% of the cholesterol goes into the broth ? How about the other good and bad things in the skin ? StuRat (talk) 19:50, 23 September 2012 (UTC)

Don't you cool the broth overnight and when it is jelly spoon the white fat off the top? Otherwise you are eating broth when your tummy is still full of the meat? Bad things on skin is a slight worry. In the old days they used oestrogen into capon necks to neuter them...my father wrote a paper on some of the effected patients who drank capon neck broth in the 1950s. --BozMo talk 20:59, 23 September 2012 (UTC)

When I first make it, I do eat it hot, all mixed together. I then cool it overnight and spoon off the fat before reheating it, though. Is the cholesterol mixed in with the fat, at the top ? StuRat (talk) 21:34, 23 September 2012 (UTC)

Yes. It is in the fat layer. It is lipophilic ("likes fat") and hydrophobic (has rabies-- just kidding! it "hates water"). Dominus Vobisdu (talk) 21:47, 23 September 2012 (UTC)

Given estrogen is fat soluble you are probably skimming most of it away and feminizing the sewer rats instead of yourself. μηδείς (talk) 22:01, 23 September 2012 (UTC)

I'm bothered by the the expression "the bad cholesterol" in StuRat's question. The whole discussion just seems to accept it as a factual basis. I've read so many conflicting reports on this stuff. Is it really so naughty? HiLo48 (talk) 23:34, 23 September 2012 (UTC)

Only on the weekends, and that's when it's off the clock. As long as its private life doesn't interfere with its job, I don't see why consenting lipids aren't left alone to do what they want in their free time. --Jayron32 02:39, 24 September 2012 (UTC)

By "bad cholesterol" I mean LDL cholesterol, with HDL cholesterol being "good cholesterol". StuRat (talk)

Well you can eat cholesterol, but you'd better not have chicken apolipoprotein running through your veins! Wnt (talk) 17:07, 24 September 2012 (UTC)

If it's not already abundantly clear, I think Wnt's point is that cholesterol is absorbed as a molecule, the HDL or LDL thing doesn't have anything to do with the absorption of the cholesterol molecule. The amount of unsaturated fatty acids in your diet might affect the HLD/LDL ratio, though. The high density of the HDLs stems from the fact that they have the highest apolipoprotein-to-cholesterol ratio. You presumably would want human apolipoproteins in your veins. The High-density lipoprotein article contains more information. --NorwegianBlue ^talk 21:06, 24 September 2012 (UTC)

Colour scheme of large macaws

Is it the case that most of the larger species of macaw parrot have evolved their brightly primary-coloured, showy plumage due to them having very few natural predators - so that being bright and standing out adds no extra evolutionary pressure? Most smaller parrots (which are presumably preyed-upon by raptors on a regular basis) are either predominantly green, or are coloured in such a way that although they may have splotches of bright colour in places on their bodies, they blend in very well with the patterns of light and shade in trees when seen from a distance. --Kurt Shaped Box (talk) 23:31, 23 September 2012 (UTC)

(There also has to be a positive reason, in this case sexual selection, for such a costly trait to be evolved or maintained. The parrots aren't just showy because they can be. μηδείς (talk) 02:04, 24 September 2012 (UTC))

So, in layman's terms, how does that apply to sexually monomorphic species, such as macaws? I was wondering myself if the bright colours helped the members of flock to locate each other over larger distances... --Kurt Shaped Box (talk) 03:00, 24 September 2012 (UTC)

Sexual selection doesn't necessarily require sexual dimorphism. Just try getting laid by any gender partner without that sexy blue ass. μηδείς (talk) 03:12, 24 September 2012 (UTC)