Wikipedia:Reference desk/Archives/Science/2012 July 5

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July 5

Why do humans seem to prefer drinks at extremes of temperature?

It occurs to me that humans on average appear to prefer either hot or cold drinks but not tepid drinks. Are there any theories on why this is the case?--108.46.98.134 (talk) 01:23, 5 July 2012 (UTC)

Warm drinks (foods in general) convey taste and odor better. I like cold drinks because they are...cooling. Agree with the question's premise, but can't think of any obvious articles. μηδείς (talk) 01:26, 5 July 2012 (UTC)

Ambient temperature is associated with stagnation and microbial contamination. It's one of the preferences which separates the amphibians and below from the reptiles and above. 75.166.192.187 (talk) 01:32, 5 July 2012 (UTC)

Interesting and somewhat plausible theory, but I can't see there being a natural preference for cold drinks in areas where humans originated. Unless maybe mountain streams? Got a source? μηδείς (talk) 01:37, 5 July 2012 (UTC)

Since most drinks are served either hot or cold, tepid would be associated with something that's been left out. I wonder if this is actually an evolved preference, or if it's just something we learn by growing up in such a society. A culinary meme, if you will. Someguy1221 (talk) 01:50, 5 July 2012 (UTC)

That's the real question right there. The benefits of cold water to the parched are so obvious that it's not surprising there are psycho-physiological mechanisms that make it desireable. And that's the thing to keep in mind here - we generally like hot or cold drinks in specific context; that is, we tend towards cool drinks when it is hot and hot drinks when it is cool, so clearly this is in part a body temperature regulation and hydration issue, which of course is entirely intuitive; we all know that and the mechanisms are known to some degree. As to the theory that tepid liquids are avoided due to their propensity to contain live parasites in relatively large numbers, that's sounds petty reasonable to me and in fact has always been the assumption I think, though of course, like many phenomena examined by evolutionary psychology of that sort, it's relatively hard to come up with firm empirical validation. But as you say, the real question is, how innate are these preferences and how much are they influenced by experience and culture? Giving my own (very hasty and very impressionistic) opinion, I'd hazard that most cultures show a preference to stay away from the middle ground where possible, and show a preference for colder or warmer drinks and that these preferences are lop-sided in such a way that persons from very cold or very warm climates will be more likely to prefer hot or cool drinks respectively more often while tepid water is probably also common amongst persons in particularly cold climates where truly cold water is not advisable. At the same time I would anticipate that people in temperate climates probably do not show as much variation on the whole. Context is everything, is basically my argument. All highly speculative, of course. It's not for nothing that a fierce trans-atlantic debate presides of the warm vs. cold beer issue, after all! And there's doubtless to be considerable individual variation owing both to psychological metabolic factors. Snow (talk) 03:51, 5 July 2012 (UTC)

I agree - I think it is cultural. When I was 6 years old, I was diagnosed with a medical condition that meant I was alergic to caffiene. So I never got used to drinking tea and coffee. I pretty much only drink water, which doesn't need to be heated. In summer I like my water refigerated, but at other times I don't care if it is tap-cool or even a bit warm. But I never ever want it hot. My friends sometimes say they cannot understand why I don't want a hot drink - I on the other hand cannot realy understand why they do want it. Cyclists and hikers get used to tepid water. Guess it's just what you are used to. Wickwack120.145.4.60 (talk) 01:56, 5 July 2012 (UTC)

It might be but the preference seem so ubiquitous and unvaried that I think it has to be more nature than nurture (even if it's a mix of the two). There are drinks that many people like that they think are repulsive at room temperature. For example many people love soda but thinks it's awful at room temperature. Adding to this might be the fact that coldness increases sensitivity to sweetness so a room temperature soda may be found cloying, but I think it's beyond that (especially when you consider that beer is the same way for many, though it's savory). I like the microbial theory but I wonder if the evolutionary time since we've had the ability and resources to choose hot or cold over unregulated temperature is long enough to have made this evolution driven (by this I mean selected for, rather than something somatically innate).--108.46.98.134 (talk) 01:59, 5 July 2012 (UTC)

Ah, I've just thought of something. Live prey (and it's blood) is hotter than the surrounding environment, and running streams, maybe from mountain meltoff, is colder than the surrounding environment. You see where I'm going with that? It would be interesting to make a study of other animal preferences.--108.46.98.134 (talk) 02:06, 5 July 2012 (UTC)

Significance is imparted to rituals by expending effort thus socially preferred norms would tend to be dictated by those preparation procedures that result in occasions that seem to have greater significance, thus when people get together to share in the act of imbibing a beverage it is likely to be a cold or hot beverage as those temperatures imply that effort was expended to arrive at those temperatures. Bus stop (talk) 02:17, 5 July 2012 (UTC)

As this is the Science Desk, I would really like to see some science in the answers. As it happens, I don't agree that humans, in general, like beverages at the extremes, and, to the extent that we appear to do is relatively modern preference. However, my opinion is not very useful. Bielle (talk) 02:23, 5 July 2012 (UTC)

On the contrary, your opinion is appreciated. It takes courage to ask the right questions, among other things.

Please see PMID 22710391. 75.166.192.187 (talk) 02:36, 5 July 2012 (UTC)

Ingeresting but one of the studies linked in the sidebar of that page came to the opposite conclusion [1]. Rmhermen (talk) 03:01, 5 July 2012 (UTC)

I believe both of them. 75.166.192.187 (talk) 03:14, 5 July 2012 (UTC)

One of those studies is looking at fluid consumption during exercise and the other at heat-exposed workers. I don't think the results can be generalized to the general population. A8875 (talk) 03:49, 5 July 2012 (UTC)

Indeed, general oral sensation is pertinent here. 75.166.192.187 (talk) 04:04, 5 July 2012 (UTC)

The preference for cold soda and beer mystifies me, because these things are more flavorful at ambient temperature, or at least, warmer temperatures than the almost-frozen American ideal. Looking at [2], the blame might go to poor quality of some of the old mass-market American beers, which are better not tasted on one's way to the vomitorium. But best not drunk to begin with... ;) Wnt (talk) 04:28, 5 July 2012 (UTC)

As a yank living in Poland, I couldn't disagree with you more. One of the things I really, really miss here is ice-cold drinks. Refrigerators for beverages in stores here are often not even switched on. Forget about getting a big fat pitcher of ice water when you sit down in a restaurant. Ice seems to be a precious commodity, and you can't just stroll over to the nearest gas station and pick up twenty pounds of ice when you have a party at your house. Even when I ask for LOTS of ice in a restaurant I usually end up with a couple of pathetic looking mini-cubes. Even ice cream is served a lot warmer than it is in the states. Looking on the bright side, I haven't had an Ice-cream headache in ten years. Another thing I really, really miss is window screening. Not like there's a shortage of mosquitoes here. Dominus Vobisdu (talk) 06:15, 5 July 2012 (UTC)

This is definitely part climate and part culture driven. Poland is a cold country, parts of the USA are warm. In England, a cold country, they drink warm beer. In Australia, a hot country, we drink ice-cold beer. And, yes, if you try Australian beer when it's warm, it tastes like vomit. Doesn't matter when it's drunk ice cold. Wickwack121.215.20.217 (talk) 06:32, 5 July 2012 (UTC)

cough cough cough When you drink "Australian domestic standard lagers" at anything above 3-5°C they taste sub-optimal. Other Australian beers, such as browns, blacks, porters, stouts, or generally ales taste quite lovely above 5°C if the drinker has actually been taught about beer. Fifelfoo (talk) 06:46, 5 July 2012 (UTC)

English ales are most definitely not served warm. If a pub serves you a room temperature pint, go somewhere else, because they don't know what they're doing. Ales should be served at cellar temperature, which is 12-14C. Fgf10 (talk) 09:34, 5 July 2012 (UTC)

I'd also dispute England being called "a cold country". --Dweller (talk) 10:53, 5 July 2012 (UTC)

And so does Wikipedia. --Dweller (talk) 10:55, 5 July 2012 (UTC)

The WP article gives the summer maximum in England as 21 C. That's about our winter maximum in most Australian cities. The lowest recorded temperature in England was -21.5 C. The lowest recorded temperature in Perth Australia was about -1 C. It routinely snows in England. We never get snow in Australia, except in high mountains. Yep - England is cold. Australia is a hot country. We know that - when British made cars were still available, Australian heat rapidly ruined upholstery and paintwork. However, beer at "cellar temperature", 12 to 14 C, would definitely be regarded as "warm" by Australians. We refigerate our beer. Wickwack60.231.243.191 (talk) 11:38, 5 July 2012 (UTC)

You should read more carefully. The section begins "England has a temperate maritime climate: it is mild..." It then cites our summer maximum as "not much higher than 32 °C", a whole 10 degrees higher than what you thought you'd read. Australia may indeed be hotter than England, but that does not mean England is "a cold country". Your argument is like saying that Scotland is a hot country because Greenland is colder. Cold countries do exist, but not in this bit of the Atlantic. --Dweller (talk) 11:54, 5 July 2012 (UTC)

Perhaps you should read more carefully, Dweller. Maybe think a bit more clearer too. I compared like with like. The WP article in the climate table gives the mean summer maximum for England as 21 C, as I said. Go look. Naturally, England will get days where this is exceeded, and in fact the same section of the same article gives the recorded maximum of 38.5 C, not 32 C. But England won't get 38.5 C at all very often. In the same way, our (Perth) mean summer maximum is 31.5 and the max recorded is 47 C, but we see ~42 C every summer. Most people in the world would regard England as cold. Comfort-wise, and thirst-wise, which are the only things relavent to the OP's question, there is a big difference between a 21 C summer and a 31 C summer. And Australia has other areas with a summer mean around 40 C. Your statement about Scotland and Greenland is meaningless in this context. The reality is that England is cold, and Greenland is extra cold - so cold that not many folk live there (the entire country has a population less than an average town). Wickwack120.145.144.189 (talk) 15:49, 5 July 2012 (UTC)

It was 22C here in the southeast of England today (phew, what a scorcher!). It might get over 30C once or twice in a summer, although it hasn't yet this year. However, we have much milder winters than our European nieghbours, so it aint all bad (sorry about your car Wickwack). Back to the subject - I agree with Fgf10 about "cellar temperature" beer, however I am quite happy to drink beer from cans and bottles at room temperature, although many youngsters prefer theirs chilled - there's no accounting for taste. But how did you foreign and Commonwealth chaps get cold beer before refridgeration? Alansplodge (talk) 22:10, 5 July 2012 (UTC)

You must be joking cause, ~20-22C is room temperature, as is, what humans make their environments on purpose when they have climate control. And Scotland Julys and Augusts wow, those are like Aprils and Octobers here, you might want to hold onto a beautiful Scottish woman just to keep from dying of hypothermia (or, you know, like put on a sweater or something). Sagittarian Milky Way (talk) 23:39, 5 July 2012 (UTC) Sagittarian Milky Way (talk) 23:39, 5 July 2012 (UTC)

Many methods existed, including chilling beer in a cold stream or root cellar, or using evaporative cooling in dry climates. Ice was also collected in winter and stored in a large, insulated warehouse, so it would last through summer. Then, industrial scale refrigeration became practical long before home refrigeration, leading to daily ice deliveries to keep iceboxes cool. StuRat (talk) 22:19, 5 July 2012 (UTC)

I know somebody called for more science above, but let me offer you few other theories based purely on personal expierience. First - drinks with carbon dioxide do taste better cold, but at certain temperature, not just generic "cold". This I learned from personal expierience with both sparkling wine (and there seems to be whole art regarding how cold it should be served) and Coca-cola. And for that reason I doubt it is just a cultural thing - that would require believing in the stereotipe and though I had heard before that these drinks taste better chilled, I never really believed it and as a matter of fact hated cold coke up to last summer, when I bought it near ice cold and found it to be way better than I'd ever had expected. Secondy tepid may taste better, because taste buds get sort of temperature shock, when it's too hot or cold. This also from expierience - I have trouble tasting how much sugar is in tea when it is very hot. And thirdly - tepid means close to body temperature, so perhaps this can confuse sense of taste too. At very least it confuses the sense of touch to point you can berely feel the fluid touching you, be it in drink or anything else. This might confuse your brain, because you may know you are drinking, but you don't fully feel it. ~~Xil (talk) 00:05, 6 July 2012 (UTC)

I'm confused what you mean by 'that would require believing in the stereotipe'. As with many things which may be at least partially cultural like the associated of pink with feminity, all it requires is people to have learnt or adapted to that association in some way which isn't surprising if it's widespread practice. The fact that one (or a small number of people) did not believe it but later found they agreed is pretty much useless. For starters, thy may still have been sufficiently exposed to the phenomenon that even if they try to disbelieve it. And for example as to your specific experience, 'coke up to last summer' suggests the circumstances could easily have affected preference. I don't think anyone has disputed people may find cold drinks better in specific circumstances like when they've been exposed to heat for a while and are perhaps even somewhat dehydrated. See for example A8875's comments. Nil Einne (talk) 07:48, 6 July 2012 (UTC)

Yeah, and that association you make is stereotype. You hear that this or that is better hot/cold and you start to believe in it - it tastes better, because you expect it to. My whole point was that I didn't have any ilusions of cold coke being tasty, matter of fact I didn't like it cold. Therefore I find that me finding it tasty cannot be explained with it being cultural thing (and probably other people will also find that they don't always find things tasty according to what society tells them, but based on their own expierience). Yeah, it was summer and obviously it could have had some effect, but since then I've been trying to select cooler coke, whith varying success and in different seasons too. Also same thing wih champagne, which I don't drink for being thirsty - nobody here really cares, if it is cooled, I technicaly knew it is recomended to cool it, but didn't think it makes much difference, untill, purely by accident, I happaned to taste it cooled. For sure climate and perhaps some traditions can explain preference in some cases, but not always - the food temperature does affect its taste. I figure it has more to do with body temperature and drink temperature being relative to it, than with culture ~~Xil (talk) 08:42, 6 July 2012 (UTC)

evidence for evolution, as opposed to adaptation.

I've been looking at the Evolution article on Wikipedia. It discusses adaptation (the process whereby an organism becomes better suited to its environment-e.g. the snake loosing its legs, whales gaining flippers, and even elephants growing trunks.) as a result of natural selection, but not evolution (the process whereby an organism grows in complexity-e.g. single celled organisms becoming multi-cellular). So what evidence is there for evolution, and how does this fit into the idea of natural selection?

I'm asking this from a genuine scientific perspective not as a naysayer, and i'm looking for answers, so creationist bashing will be pointless and annoying. — Preceding unsigned comment added by 86.176.99.114 (talk) 12:39, 5 July 2012 (UTC)

For what it's worth my understanding of evolution includes both processes you mention. Simple organisms may become more complex if it affords them some advantage in survival or already complex organisms may undergo alterations in their make up if these alterations afford them some advantage in changing circumstances or using the present circumstances in a more efficient way. Evolution is (usually) a slow process, the changes may take place over thousands of years which effectively make them invisible to human beings (were it not for fossils). — Preceding unsigned comment added by 86.4.184.18 (talk) 12:56, 5 July 2012 (UTC)

yes but surely single celled organisms are the ultimate replicating machines, so why would a gene ever be passed on to the next generation if it encourages multicellular organisms.

While it's true that the life cycle of single celled organisms is typically significantly faster than those which are multicellular, this does not necessarily equate to the best survival/reproduction strategy. Most adaptations do come with a price (a species may develop a new organ that is incredibly useful in a new environment but require additional sustenance to support it or a species that previously benefited from having large numbers of offspring, any which of might propagate its genes, could adapt to have fewer young that it devotes more resources towards on an individual basis. In each case, its immaterial to the gene which strategy leads to its replication, so long as said continuation occurs, and for each organism there are multiple genes that all operate under "selfish" principles but which are bound by a mostly common fate (aside from the random mutations which drive evolution and the re-combinatorial aspect of sexual reproduction). Life evolved from single-celled organisms because some of the afore-mentioned random mutations led to new (multicellular) forms whose complexity allowed them to out-compete their unicellular counterparts. Sure, a bacteria may be able to reproduce thousands to millions of times within the lifecycle of certain "higher" organisms, but those more complex organisms will likely get to reproduce more times. At the end of the day, the gene that survives for 1000 generations that are a day long each (say a gene in a mayfly) has been exactly as "successful" as a gene that survived for one generation of a thousand years in a redwood tree, though they may have very different long-term chances moving forward. I think the missing piece of the equation you might be looking for is chance. Mutations occur constantly in living organisms and are simply the result of the basic bio-physical properties of the matter that they are constructed of. Virtually all mutations are non-conductive to the organism's chances of surviving, but rarely a mutation leads to a change in the organism that, just by chance and no more elementary principle, happens to up the organism's odds of surviving long enough to pass on its genes. And even amongst this subset of lucky benefactors, most will not survive, because they are still in a wide and uncertain world of competing organisms. But over enough time, these beneficial traits begin to accrue just through probability and the result is increasingly complex organisms that are descendents of those happy few who just happened to have the right adaptations in the right place at the right time. Snow (talk) 16:23, 5 July 2012 (UTC)

The idea that evolution somehow favours complexity is false ; [[3]] is a "primitive" organism which descended from "more advanced"/"more complex" canines. 157.193.175.207 (talk) 12:58, 5 July 2012 (UTC)  : The idea that evolution somehow favours complexity is false ; [[4]] is a "primitive" organism which descended from "more advanced"/"more complex" canines. 157.193.175.207 (talk) 12:58, 5 July 2012 (UTC)

− − ::my point exactly. so why do complex organisms exist?

While it's by no means a complete answer to your question, I suspect that you'll find our article on dictyostelium discoideum of interest. It is a slime mold that sits squarely on the border between uni- and multicellularity. TenOfAllTrades(talk) 13:16, 5 July 2012 (UTC)

86.176.99.114—"Natural selection" is the mechanism of "evolution". Natural selection is terminology for survival and reproduction. That organism which fails to survive and reproduce also fails to pass on traits to a next generation. Success at passing on traits (encoded in genes) drives evolution. There are other factors, but I am just addressing one of the basic ideas involving evolution. Bus stop (talk) 14:00, 5 July 2012 (UTC)

Yep. There is no built-in evolution to greater complexity in the sense that the Original Poster used. That's not what is meant by "evolution" when biologists use the word. What has happened is that a mutation of single-celled organisms gave then the ability to do well in some niche environment when a number of them are clumped together; then another mutation gave some level of specialisation which better suited some other niche environment. And so on... The result after a vast number of years and much change in environment is a distribution of organisms over a range of complexity, and the number of organisms of any complexity is roughly inversely proportional to complexity. This is clearly illustrated by considering a human. One (1) healthy human has in his body about 10 times the number of micro-organisms than human cells. Wickwack120.145.144.189 (talk) 15:25, 5 July 2012 (UTC)

Genetically speaking, multicellular organisms aren't really more complex than related single celled organisms. Notably, consider amoeba, e.g. Polychaos dubium, which our article says contains 670 billion bp as opposed to just 2.9 for the human genome. Single cells can have "eyes" (see Dinoflagellate), "legs" (i.e. pseudopods), "kidneys" (i.e. contractile vacuole), and can engage in some fairly impressive behavioral feats (e.g. Mycetozoa solving a maze, if they count, or the fast and purposeful swimming of the Paramecium). Now what is true is that there is a general power law about viscosity and drag - if you want to move fast, make great migrations from pole to pole, or even up and down the tidal zone, you need a big body; and for a big body to work you need some kind of increased internal surface area for cells to respire and acquire nutrients, which is pretty close to an order for multicellularity. (Though true, as our skeletal muscles do, the outside environment could be brought to the inside of a larger syncytium through tubules; if that can scale up to a whole organism though, nobody's done it) Now because there are ecological niches that require varying degrees of fast mobility, and because fast mobility virtually decrees multicellularity, it is inevitable that evolution will come up with big organisms eventually that can fill those niches, because the ones that get started on the task will prosper. Wnt (talk) 15:41, 5 July 2012 (UTC)

First let me clarify some terminology - it might help the articles make more sense. "Evolution" just refers to any and all change in a group of organisms over time. This can mean any change including random characters getting fixed by chance through genetic drift. (See the Evolution#Mechanisms section for other ways of evolution taking place.) Natural selection is just one way in which evolution occurs. Evolution by natural selection may lead to an organism being better suited to its environment (e.g. fur color in mice that move to a desert becoming lighter) or it may not (e.g. spread of ultraselfish DNA. see Intragenomic conflict).

Other than the terminolgy, I see two questions here - Why does complexity (multicellularity) evolve? and What evidence/examples do we have for it?

For the first question, the usual reason for an organism to get more complex (unicellular to multicellular, complex tissues and organs, complex nervous systems etc.) is to be able to better deal with other organisms. These reasons include avoiding predators (bacteria and algae form biofilms, many algae are colonial), becoming more efficient predators or beating competition - in land plants erect stems will hog all the sunlight and kill off simple green goo on the mud, a multicellular fungus can put resources gathered from a large area into growth, bigger animals can move faster etc. Much complexity comes to solve problems created by other complex innovations. A bigger body with more muscles helps you avoid prey, but now a nervous system will go a long way in making it coordinated. However, depending on the exact selective pressures and the chance factors involved, evolution can progress towards simplification (lean and efficient) or complexity (eat/roll over everyone else with impunity)

For the second question about evidence/examples the most common evidence is to construct a phylogenetic tree based on DNA and other characters. In the most likely tree it, we look for all the points where a group of organisms all inherited a complex trait from a common ancestor. For example, this way we can find several cyanobacteria that are multicellular but have close unicellular relatives. See the article on multicellular organisms. also have a look at [5] for an idea of how it's done.

Hope this has been helpful Staticd (talk) 18:01, 5 July 2012 (UTC)

ok thanks, i get what you're saying. can this process be empirically proved? — Preceding unsigned comment added by 86.176.99.114 (talk) 20:15, 5 July 2012 (UTC)

Well, Chlorella vulgaris repeatedly evolves a colonial habit to evade predation in the lab. But I doubt it's known that it's never colonial in the wild, or in its history... still I tend to think that it evolves pretty easily; the question is only whether the environment is pushing the organism to do so. See [6] for a nice paper. Wnt (talk) 00:49, 6 July 2012 (UTC)

Can Evolution be proved empirically? The short answer is 'Yes'. The long answer depends on your definitions. Evolution is both a fact and a theory (see Evolution as a fact and theory). The fact of evolution is the observation that evolution occurs. We've seen it happen in the lab, and in the wild. We came up with the Theory of Evolution to explain the fact of evolution. It has since become one of the most well supported theories in all of science. See Evidence for evolution; there's a lot of it, from a number of different disciplines. We use evolution to create medicine, create new "kinds" of animals, develop technology, understand biology, and so forth. It's a cornerstone of biology nowadays, and that's because it's been demonstrated to work. In a colloquial sense, I think that applies as empirical proof. However, you must understand that science doesn't work in "proofs"; nothing in science is ever "proved", ever. The theory of gravity isn't proved, or germ theory, or any other. When a hypothesis becomes well tested and accepted within the scientific community as true (to the best of our current ability to understand it), it graduates to become a theory. That's the "highest rank" in science, and if anything qualifies for it, it's the theory of evolution. Take a look at the articles I linked to above, including Objections to evolution; hopefully they'll clear things up better than I can.   — Jess· Δ♥ 03:48, 6 July 2012 (UTC)

Heat Transfer

Im assuming that the equation Q=hA(dT) is needed to find the heat transfer rate through an igloo given that it's diameter is 3m, the temperature inside the igloo is 5C and the temperature outside is -20C, the heat transfer coefficient between air and ice is 10W/m^2K and the thermal conductivity of ice is 0.5W/mK. I would use a=pid^2/2 to find the area of the igloo as the diameter is given. This gives me a value of 3534.29J/S. However given all this info, is it possible to find the temperature inside the igloo at which the ice would start to melt? I can't see how you can do this without the heat transfer coefficient between ice and air but I'm not sure how to obtain this from the data available. 176.27.210.194 (talk) 13:28, 5 July 2012 (UTC)

To find the internal air temperature required to begin melting the ice, you only need the air-to-ice transfer coeficient (you gave that as 10W/m².K) and the heat (in watts) flowing thru the ice. You can't calculate the heat flow thru the ice though, becuase although you have the thermal conductivity of the ice, the temperature difference of the ice and the outside ice-air interface (10W/m².K again) in series (it's 0 C on the inside and -20 C on the outside) but not the ice thickness. You need the ice thickness. Ratbone121.221.80.11 (talk) 15:14, 5 July 2012 (UTC)

the ice thickness is 0.1m but I still don't see how you can calculate the internal air temp required to begin melting the ice without the heat transfer coefficient between ice and air. I came up with the equation Q=A dT/(1/hi+t/k+1/ha) where hi is the heat transfer coefficient between ice and air and ha is the heat transfer coefficient between air and ice? 176.27.210.194 (talk) 15:36, 5 July 2012 (UTC)

Just consider how you would derive that equation. Take the temperature inside to be T1, the temperature at the incide air-ice boundary to be T2, the temperature of the outside ice air boundary to be T3 and the ambient outside temperature to be T4. You then assume steady state, so

hi (T1-T2) = k/t (T2-T3) = ha (T4-T3). You then have 2 equations allowing you to eliminate the two intermediary temepratures T2 and T3, so that you can write Q in terms of T1 and T4 only, yielding the eqation you give. But now you are interested in T2, because if this becomes larger than 0°C the ice will melt. Count Iblis (talk) 16:03, 5 July 2012 (UTC)

[Edit conflict]You gave in your original post the heat transfer coefficient between ice and air as 10W/m².K. It works the same in both directions. You have the ice thickness (0.1 m) and the ice thermal conductivity (0.5W/m.K). Use the geometric mean of inside area and outside area. So you can calculate the ice thermal resistance R_ice. You have the iglos outside diameter (3 + 2x0.1 m), so you can calculate the igloo outside area. With the igloo outsid area and the ice-air transfer coeficient (10W/m².K) you can calculate the outside ice-air notional thermal resistance, R_ice-air. The total thermal resistance, inside ice surface to outside ambient is the sum of these two resistances. So now you have a resistance with a ΔT of 20 K (inside surface just melting so its 0 C, outside ambient is -20 C). So you can now calculate the heat flow, Q = ΔT/(R_ice+R_ice-air). And, now that you have the heat flow, you can, with the inside air-ice inteface, calculate the required inside air temperature. Ratbone58.170.169.167 (talk) 16:39, 5 July 2012 (UTC)

2012 summer weather

Why is the summer weather this year cooler than the average temperature from the last few years everywhere in the northern hemisphere? Clover345 (talk) 15:15, 5 July 2012 (UTC)

Not everywhere (just ask the people in the US who don't have power right now how they are doing without AC). In North Western Europe we've had rainy and cooler weather because the Jet Stream is not as far North as it should be. Count Iblis (talk) 15:55, 5 July 2012 (UTC)

has this affected Southern Europe? Clover345 (talk) 16:03, 5 July 2012 (UTC)

They have had hot weather there, temperatures have been above 40°C in Spain. But this has affected parts of Southern Europe, it has caused more rain in some places. Count Iblis (talk) 16:25, 5 July 2012 (UTC)

The OP's question has false assumptions. Throughout the Northern Hemisphere there were areas with record or near-record warmth in the past month. Seoul, South Korea and Denver, Colorado (US) had their hottest June on record, while Malta had its second-warmest June on record. In Puerto Rico, June 2012 was the hottest of any month on record. And I found these just with a quick google search.

I assume the OP is from the UK, where temperatures have recently been below normal. That's the way that weather works, record high temperatures in one area often mean that other areas at the same latitude will be below normal, and vice versa. That's because temperatures are roughly zero-sum; the principal cause of abnormal temperatures is abnormally amplified Rossby waves, which send cold, arctic air much further south than it normally would be, and conversely sends warm, tropical air much further north than it normally would be. This image illustrates it quite nicely.-RunningOnBrains^(talk) 18:01, 5 July 2012 (UTC)

We've broken many records for hi tempos here in Detroit, too, including 101°F just yesterday, which was a record for July 4th. StuRat (talk) 00:42, 6 July 2012 (UTC)

were entering a ice age — Preceding unsigned comment added by 74.74.255.141 (talk) 03:11, 6 July 2012 (UTC)

Anal flu

I tried to look this one up a while back, but never came on a satisfactory answer. Suppose a person is somehow exposed with influenza solely by anus, e.g. by contaminated toilet paper at a public restroom. What will the course of the infection be like?

• Will the flu quickly travel through the bloodstream to the lungs and cause a normal infection?
• Will it cause a milder infection because the immune system gets a crack at the virus before it gets a crack at the lungs?
• Will it cause weird, bizarre symptoms, your rectal lining falling out in strips or something?

In the most optimistic view, I'm thinking it might be a way to evade Captain Trips...

Wnt (talk) 16:03, 5 July 2012 (UTC)

Diseases do differ in effects according to how they are transmitted, with respiratory anthrax, for example, being much deadlier than the other kinds. There is what's called the stomach flu, although it usually isn't even from the flu virus, and it enters orally. What in the world that you would be doing with toilet paper that it got in your colon I cannot imagine. The Infection would likely be largely limited to the lower intestine, since there isn't significant backwards flow, and the flu virus mostly just infects epithelial cells of the mucosal tissue, with the ache and fever causing chemicals travelling in the blood being part of the immune response, not viruses or infected blood. So yes, it might work as a sort of suppository inoculation. μηδείς (talk) 16:18, 5 July 2012 (UTC)

Flu virus have evolved so they are optimised to multiply in the uppr respiratory tract. So, for a typical flu, the ansers to your questions in order are, No, Yes - very much so, assuming the immune system even notices it, and No. However, flu viruses can range from hardly infective to absolutely rampant. So, for the purpose of the Captain Trips story, yes , a realy bad bug could get going via someone's fundametal orrifice. But plenty of humans don't even wash their hands, let alone wash in a way that prevents bug transfer. Have you seen how nurses in a hospital wash their hands? They turn on and turn off the taps with their elbows - this is the only way to prevent hand-tap-hand transmission of bugs. Plenty of humans pick their nose etc right after wiping anyway. In many countries there is no facility to wash. So your question is almost certainly not relavent. Wickwack58.164.237.212 (talk) 16:20, 5 July 2012 (UTC)

Most pathogens have a fairly restrictive epidemiology, meaning they have a very specific gambit in how they reproduce, including highly refined mechanisms to get into and out of the various tissues they need to exploit for their life cycle. Some are less picky than others, of course, and some are happy opportunists who are streamlined to infect you in one way but are capable of taking advantage of uncommon circumstances to propagate. You have perhaps heard the story going around in the popular press right now of a young American woman who recently lost multiple limbs to flesh-eating bacteria after she gashed her leg open in a swimming incident. The bacteria in question was not some rare species from deep in the Congo but rather a commonplace strain of Strep B, the stuff that usually gives you a sore throat at worse. It was just a case of the bacteria getting the drop on an immune system that was unable to adapt in time to keep the bacteria from replicating far beyond what it would usually be capable of inside a host. One famous example of a very opportunistic Yersinia pestis -- you probably know him from his more common and charming monicker the Black Plague. Those infected with plague will manifest symptoms in one or more of three clinical categories defined by the systems hit hardest by the bacteria - bubonic plague (infected lymphnodes), pneumonic plague (infected lungs), and Septicemic plague (infected blood). Blood infections are almost always one of the worst case scenario's for a given pathogen, since a blood infection means that A) the immune system is already doing a bad job of containing the pathogen since it does a lot of its work through the blood and B) the pathogen now has a free ride to virtually any organ/tissue where it might flourish. Note though that it may not be in the pathogen's best interest to spread too fast, since it may be a type that tends to preserve its host as long as possible so that it can spread to still new hosts. All of that said, viruses are typically more "picky" than bacteria - they usually follow a much more predictable approach, though they can also be much more virulent -- in terms of just how resistant they can be to the immune system and the severity of the symptoms they cause -- once they are established. Snow (talk) 17:06, 5 July 2012 (UTC)

Higgs field

Why isn't the Higgs field a preferred reference frame, in violation of relativity? --108.225.117.142 (talk) 17:13, 5 July 2012 (UTC)

Because it is a scalar. Then, despite it having a nonzero vacuum expectation value, the vacuum is still Lorentz invariant. And it wouldn't violate special relativity for a vector field to get a nonzero vacuum expectation value and thereby to spontaneously break Lorentz symmetry. Count Iblis (talk) 17:22, 5 July 2012 (UTC)

But isn't the point of relativity that you can't say for sure that Frame A is stationary and Frame B is moving, because B could be stationary with A moving in the opposite direction? But can't you be certain that the Higgs field is stationary and anything that moves relative to it is actually moving? --108.225.117.142 (talk) 17:35, 5 July 2012 (UTC)

Note that scalar fields include gravitational and electrostatic potential. The point is, a particle with a +1 charge has a +1 charge no matter how fast it is going relative to you, and I assume the same applies here. (Not that I understand the Higgs mechanism really!) Wnt (talk) 19:01, 5 July 2012 (UTC)

The vacuum (with the Higgs field) looks just the same to both observers. Count Iblis (talk) 02:33, 6 July 2012 (UTC)

Waste heat differential recycling in air conditioning

Given that window mounted ACs try to have the condensate run over to the condenser to help cool it by evaporating, thereby recouping the energy expended to condense the warer vapor, I notice that central ACs don't seem to do that; they pipe the condensate outside and just dump it. However, they pipe it all the way out next to the external housing, and dump it there. Why don't they just spring for the additional foot of tubing and let the condensate pour onto the condenser coils? The waste in energy must be significant. Gzuckier (talk) 20:06, 5 July 2012 (UTC)

Many do, but the use of maximum efficiency designs is hampered by their complexity, sometimes. In many cases waste heat recycling upgrades can be much more efficient, but if the body was designed and painted with air/liquid surface use assumptions, which is very likely, then waste heat energy differential use improvements can be major upgrades. Often, replacement of the primary components can cause increased efficiencies, too. Infrastructure upgrades are well worth the investment. 75.166.192.187 (talk) 20:51, 5 July 2012 (UTC)

I've noticed some of the problems that my window A/C has, due to this efficiency improvement:

1) Rather than draining the condensate, they pool it for reuse, which allows microbes to grow in the condensate. Mine blows out mold spores after I first turn it on. I'd gladly accept lower efficiency if I could prevent this.

2) The way the fan dips into the pooled water to splash it on the cooling fins makes a horrible noise, rather than the smooth, continuous sound it would make otherwise.

3) I wonder if the added load on the fan shortens it's life.

So, like with any efficiency improvement, there are trade-offs. Apparently the makers of window units think their customers are more willing to put up with the inconvenience to save money than those with whole house A/C. StuRat (talk) 00:50, 6 July 2012 (UTC)

What you have are the symptoms of a blocked condensate drain, and it is a health hazard. Sometimes insects crawl in and block it, particularly if the aircon is not used for a few days. Or the aircon may have been incorrectly installed - some have 2 optional ports on the condensate tray for drain hoses, which mean the aircon comes from the factory with both ports blocked, and installers forget to install a drain hose. Indeed, the vibration caused by fan blades hitting water will not be good for it. Note that in a window mounted "unit aircon", the evaporator and the condenser are at the same height, so to run condensate (which comes from the evap) over the condenser, you'd need a pump. Ratbone120.145.45.13 (talk) 03:02, 6 July 2012 (UTC)

And, to avoid the expense of a pump, they just let the fan hit the pool of condensate water, which splashes some of it on to the cooling fins, and call that "good enough". StuRat (talk) 07:11, 6 July 2012 (UTC)

You're not listening, Stu. It's not normal for the fan to touch water. It's not good for it. It's not meant to. If yours does that, it's faulty. Ratbone121.221.79.93 (talk) 08:03, 6 July 2012 (UTC)

It's not a bug, it's a feature. There are fans which splash in a pool of condensate: it's called a "slinger ring", that surrounds the fan and directs water into the coils. I think in part it's intended to evaporate as much condensate as possible to avoid excessive drippage on people and things below, with the added benefit of improving efficiency. Piped condensate usually drains by gravity, nearly always to a place that's convenient for discreet drainage and not suitable for use to augment the condenser. Acroterion (talk) 21:46, 6 July 2012 (UTC)

Ratbone, haven't you ever noticed that a window A/C unit makes a horrible sound like a dead squirrel grinding between gears ? That's caused by the fan hitting the water, which unbalances it. StuRat (talk) 04:22, 7 July 2012 (UTC)

While we have squirrels here in Australia (they aren't native - it appears they escaped from zoos), I've never tried grinding one with gears - I'm not at all sure what that would sound like. But a fan hitting water certainly would make an obnoxious noise. You must have really strange aircons in America! Although an electronics engineer by qualification, I have ~10 years experience as a building/property manager, so I do know a thing or 2 about airconditioning - I've spent lots of employer's money on them, inspected installations, issued tender specifications, etc. I've never seen a fan deliberately used to sling condensate water, and I have seen the innards of lots of Australian, Japanese, and Chinese made unit aircons. And with all of them, unless they are worn out, all you hear is the soft sigh of air being blown, and maybe a bit of compressor noise if it is old and doesn't use a rotary or scroll compressor. Not only the fan slingling water would be noisy and vibrate your wall, it would be a health hazzard. You sure yours isn't faulty? Ratbone121.215.60.81 (talk) 05:13, 7 July 2012 (UTC)

Well, I'd call the design faulty, even though it is "working as designed". I'm not sure if you can get a window A/C unit here that doesn't use this annoying little cheat. Looks like we both learned something new today. You learned that this method exists, and I've learned that it's not ubiquitous. StuRat (talk) 07:33, 7 July 2012 (UTC)

Come to think about it, this sound is so common here, that if any window A/C unit didn't make this annoying noise, an American might think it was broken and return it. StuRat (talk) 07:42, 7 July 2012 (UTC)

Just in case you're not conviced that the slinger ring exists: "Water hitting condenser fan blade ? This is normal. Most window ac's have what they call a slinger ring. It's a ring that runs around the outer edge of the condenser fan blade and slings water up on the condenser coil to help it cool better." [7]. Here's a pic of a fan with a slinger ring: [8]. StuRat (talk) 07:52, 7 July 2012 (UTC)

Yep, Stu, we've both learnt something. After looking at your links I did a bit of googling, which perhaps I should have before. I learnt several things that may be of interest to you: (1) Slinger rings are covered by US patent 7398654 issued to LG Electronics, a Korean company, in 2002. This is at about the time I left employment having to do with airconditioners, so that's why I had never heard of it. (2) Since a slinger ring must necesarily be on the CONDENSOR fan, and the condensate water comes form the evaporator, on the room side of the internal partition, there must be TWO water trays, an "inside" one and an "outside" one, and a communicating port to give gravity flow of water from the inside tray to the outside tray. (3) the slinger ring is specially shaped and dimensioned to pick up water by viscous attachment, not scooping, and so causing a minimum of noise and vibration.

From this, I infer the following (bear in mind I've never seen such a thing):- (a) If yours makes an annoying noise, it could be because the communicating port is blocked, leading to the INSIDE tray becoming overfull, and the EVAPORATOR fan/blower blades hitting water. Blockage could be due to insects if the airconm has not been used for a while, or you have had a period of very low humidity weather. Since the evap fan is not designed for it, you will get a lot of noise. (b) the operation of such a system is dependent on humidity. In climates combining high temperatures and high humidity, the production of condensate could overwhelm the communicating port, again leading to the EVAP fan hitting water. In such climates I expect that the installer is supposed to fit a good old drain hose. In any case, if you don't like the noise, fit a hose - end of problem. (c) The patent provides for more than one slinger ring. This could allow wasps to set up their mud homes between the rings. This would give a scooping effect, resulting in much noise and vibration. Ratbone124.182.21.29 (talk) 09:46, 7 July 2012 (UTC)

I really don't think there's anything wrong with my A/C, as every window A/C I've ever seen makes the same annoying noise. I'm a bit skeptical about this "viscous attachment"; when a rapidly moving disk attached to fan blades hits water, it's going to splash, and cause an imbalance in the fan, both of which create the characteristic (American) "window A/C noise". Perhaps with a slower disk, lacking fan blades, and a thicker fluid, like oil, you might avoid this. StuRat (talk) 02:18, 8 July 2012 (UTC)

The patent description implies a slinger ring that is actually a flat disc continuously immersed, so yes, there should be no splashing, only fine droplets thrown up. Ratbone121.221.221.138 (talk) 06:56, 8 July 2012 (UTC)

I'd call slinging fine droplets "splashing", as it will make some sound (imagine a dripping faucet, now crank the speed way up). A full disk, versus the fan-disk hybrid I showed, might be better, but still not silent. StuRat (talk) 17:42, 8 July 2012 (UTC)

Nope. As each fine droplet lands on something, it will make a very short duration "tap" sound. A large number of such "taps" will constitute shot noise, which sounds much the same as wind noise or thermal noise in electronics. See http://en.wikipedia.org/wiki/Shot_noise, but bear in mind that although the WP article implies shot noise is just an electronics phenomenom, shot noise is in fact a noise source common to all physical systems where particles hit a surface. This is a well known phenomenon to engineers - no way will it sound like splashing. But if you don't like the noise, whatever it may be, fit a drain hose. Ratbone60.230.213.208 (talk) 01:05, 9 July 2012 (UTC)

It doesn't sound like splashing, it sounds like grinding. And sandblasting also makes a hell of a noise, even though each grain doesn't seem like much. StuRat (talk) 05:07, 9 July 2012 (UTC)

<undent>My mid-1980s-vintage Gibson A/C unit has a slinger ring: I suspect the LG patent is intended to address the annoying noise issue rather than the entire slinger ring concept. The Gibson makes a particularly vile splashing noise on start-up. As Ratbone speculates, there's an insulated tray that collects condensate on the evaporator side, and it dribbles through a small channel to a sump on the condenser side, into which the ringed fan dips. I suspect that much of the effect depends on the local humidity: here in the US mid-Atlantic, summers are insanely humid and there are great quantities of condensate available. Acroterion (talk) 03:23, 8 July 2012 (UTC)

Yea, I've heard that characteristic sound (something like a garbage disposal) all my life, so some version of the slinger ring must go way back. StuRat (talk) 05:09, 9 July 2012 (UTC)

Kayaking and physics

When I'm teaching kayak skills to children, I sometimes fill an idle moment by showing them the "helicopter turn" in which you spin your paddles around above your head, which causes the kayak to rotate in the opposite direction - rather pointless but quite amusing for a short while. I tell them that this is because every action has an equal and opposite reaction, a fact dimly remembered from school many years since. However, last night, a Scout Leader told me that it was caused by "conservation of linear momentum", a concept that is entirely unknown to me. Was he right and if so, what does it mean? Alansplodge (talk) 21:39, 5 July 2012 (UTC)

Actually, it would be the "conservation of angular momentum" (spin momentum). In simple terms, a new rotation in one direction must be countered by a rotation in the opposite direction. The kayak will rotate more slowly, though, both because it has a higher mass, and because that mass is farther from the center (the term for this combination of mass and distance from the center is the moment of inertia). However, this is really part of the "every action has an equal and opposite reaction" rule, which is the third of Newton's laws. To put it in a math formula, we'd have:

Ipωp = Ikωk

Where:

Ip = moment of inertia of paddle

ωp = rotational velocity of paddle

Ik = moment of inertia of kayak

ωk = rotational velocity of kayak

Unfortunately, the moments of inertia aren't that easy to calculate, and vary depending on the axis of rotation, so you probably can't apply this formula yourself. StuRat (talk) 21:45, 5 July 2012 (UTC)

the conservation of momentum (angular and linear) and "Newton's third law" are the same. Newtons laws talk in terms of forces. You carry out some action (apply force) on a body and it gives you and equal and opposite reaction ( a force on you). If you apply Newton's second law (Force=mass*acceleration ) on both the body and yourself to see how much both of you accelerated you can calculate how the two of you will move. A neater way of getting the final velocities of both bodies is to skip forces altogether and just say that momentum is conserved (Mass₁Velocity₁=Mass₂Velocity₂)

Here is a small derivation showing their equivalence-

Force₁=Force₂ (Newtons 3^rd law)

Mass₁Acceleration₁=Mass₂Acceleration₂

If force is applied for time 't'

Mass₁Acceleration₁t=Mass₂Acceleration₂t

Mass₁Velocity₁=Mass₂Velocity₂ (because acceleration*time=velocity)

Depending on the circumstance, you will use one or the other to predict how they will move. for example, when a bullet leaves a gun, the forces applied by the explosion on the gun, the bullet and the gasses of the muzzle flash are really hairy. So you just invoke conservation of momentum to calculate the velocity of the bullet or the gun recoil. On the other hand, in your kayak example, the moments of inertia and the frictional forces are really complicated. Some of the angular momentum is absorbed by the water and some by the air; though momentum is conserved, it is conserved in the air-paddle-person-kayak-water system. measuring how its distributed is really tough. ( I_paddleω_paddle + I_airω_air = I_kayakω_kayak +I_waterω_water ) Hence its just simpler to solve it by using newtons laws and correct the two forces by easily measurable frictional force.

Staticd (talk) 13:36, 6 July 2012 (UTC)

I was ignoring the angular momentum of air and water as insignificant. I still consider the air to be insignificant, but the water may make a noticeable difference. StuRat (talk) 02:12, 7 July 2012 (UTC)

You can see a video of the same kind of thing [9]. When the wheel spins one way (in the horizontal plane) the chair spins the other. Chris (talk) 20:36, 6 July 2012 (UTC)

Thank you all - I got most of it. Good old Isaac. Alansplodge (talk) 00:51, 7 July 2012 (UTC)

Resolved

LHC energy compared to mosquito

Using data from here: http://www.speedofanimals.com/animals/mosquito and here http://en.wikipedia.org/wiki/Orders_of_magnitude_%28mass%29 I compared the energy of a mosquito with the energy of the LHC at cern (4 TeV). I got 2.242 * 10 ^12 eV = 0.2 TeV for the mosquito. Is this realistic? --helohe (talk) 21:49, 5 July 2012 (UTC)

2.242 * 10¹² eV would be 2 TeV, not 0.2 TeV, but yes, I think that's about right. You can find a lot of similar claims in a search for lhc mosquito. -- BenRG (talk) 22:52, 5 July 2012 (UTC)

This LHC outreach page provides some other comparisons to macroscopic objects and phenomena to give an idea of the total (rather than the per-particle) beam energy. Running full-out, the two LHC beams contain enough energy to melt nearly a ton of copper, or to accelerate a TGV (high-speed train) to 150 km/h. The LHC's 'beam dump' system is a rather interesting bit of engineering in itself: a seven-meter cylinder of graphite in a water-cooled steel shell, contained within 750 tons of iron and concrete shielding. TenOfAllTrades(talk) 13:17, 6 July 2012 (UTC)

What sort of eye color is considered black?

In several books I've read there are characters with black eyes (mostly it's American Indians and other dark skined people who have them). I find this quite hard to picture as long as aniridia is not in the picture. I did look in the article on eye color, but it mentions no such color. So is black eye color even possible? If not then what is it - extremely dark brown? If so, how dark? ~~Xil (talk) 22:21, 5 July 2012 (UTC)

I think it is extremely dark brown, and it's so dark that it looks black. I had a friend with eyes like this, she was from the Dominican Republic. 109.97.163.148 (talk) 22:44, 5 July 2012 (UTC)

My wife (75% Han Chinese, 25% North Korean by ethnicity) has "black" eyes. They're just really dark brown such that under normal lighting and distance conditions you can't see the pupil boundaries. If you got up in her face with a pen light you'd have more success. The Masked Booby (talk) 01:53, 6 July 2012 (UTC)

I had girlfriend (part italian, part asian) once, whose eyes looked black in most indoor lighting conditions, but were actually very dark brown. Really really pretty. But nearly impossible to tell what mood she was in. Ratbone120.145.45.13 (talk) 03:12, 6 July 2012 (UTC)

If you're basing your interpretation of your girlfriend's mood purely on pupilary reflex, I think you're in for trouble from the start! Snow (talk) 05:18, 6 July 2012 (UTC)

Black eyes are really more purple than anything else, at least at the start. As they heal, they turn sort of greenish, then light yellow, then fade back to normal skin tone. --Trovatore (talk) 05:25, 6 July 2012 (UTC)

That is not what the OP wanted to know. He wanted to know about people with black iridia in their eyes. Whoop whoop pull up ^{Bitching Betty | Averted crashes} 05:32, 6 July 2012 (UTC)

Very funny. I had thought that explictly stating eye color will suffice and I don't need to state that it is not about hematoma, rather about melanin concentration in iris and possibly human races. I merely figured that it might be some other dark color or indeed something more black looking. So from answers I take it's something like this example from that article? ~~Xil (talk) 08:04, 6 July 2012 (UTC)

A documented side effect of eyedrops for glaucoma e.g. Xalatan is darkening of the iris which I have observed approaching brown-black like in this. DriveByWire (talk) 12:10, 6 July 2012 (UTC)

Academic sources for nutrition

I'm looking for information relating to nutrition. I'm having trouble finding sources which aren't inherently biased and/or low quality. I'm looking for something like PubMed for nutrition, where high quality, technical information is discussed objectively without promoting a particular view. Searching google scholar, I can find some information, but the content is usually too specific (for example, discussing nutritional deficiencies in a particular group studied, or the production process of a particular food).

As one example, I'm trying to compare the nutritional value of cow's milk with almond milk and soy milk. On google, "almond milk vs soy milk vs cow milk" yields sources all saying different things. Result 1 is MSNBC, which says cows milk wins in just about every category. Results 2-4 say the opposite, but even they don't seem to match up in details; (2) is a forum post, (3) is selling organic products on amazon, and so forth. I was recommended sites like "almondmilkbenefits.org", an obviously non-neutral source with an anonymous author. On google scholar, searching for "almond milk" gets nowhere close to nutrition. Our own article is extremely lacking.

Is there a good place to find this information? I'd be happy with anything from a basic summary (supported by sources) to in-depth scientific papers. I just want something on the topic that I can trust, and potentially then use on wikipedia to meet, say, WP:MEDRS. Thanks!   — Jess· Δ♥ 23:35, 5 July 2012 (UTC)

PubMed is for nutrition. Do you know how to select the WP:MEDRS sources, e.g., the reviews and meta-analyses? They recently changed it again. PMID 22331683, PMID 17410674 (similar title, different author), and PMID 12487214 might be good places to start, although that last one is probably more for infants than adults. 75.166.192.187 (talk) 00:26, 6 July 2012 (UTC)

Unfortunately this whole area is plagued by weak science, and there is no absolutely reliable source of overview information. The best thing I can suggest in general is to use PubMed or Google Scholar to locate information, but then you will have to judge for yourself how much to rely on it. Looie496 (talk) 01:28, 6 July 2012 (UTC)

http://www.ajcn.org/ Count Iblis (talk) 02:27, 6 July 2012 (UTC)

I find http://www.nutritiondata.com to be useful. (They have nutrition info on soy milk and cow's milk, but don't seem to have any on almond milk, yet.) And, while that site gives far more info on the products they analyze, just reading the labels gives you a fair amount of info for a comparison. StuRat (talk) 06:55, 6 July 2012 (UTC)

Thank you everyone for the sources. I was giving it a bit of time for everyone to comment, and I appreciate the participation; I'm sure these will be helpful to me. I'll see if I can track down the info I need from one of those links. All the best,   — Jess· Δ♥ 04:51, 9 July 2012 (UTC)