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{{Wikipedia:Reference_desk/Archives/Science/2011 June 25}}

{{Wikipedia:Reference_desk/Archives/Science/2011 June 26}}

= June 27 =

== What is the biggest [[Humpback whale]] ever found? ==

What is the biggest [[humpback whale]] ever found? [[User:Neptunekh2|Neptunekh2]] ([[User talk:Neptunekh2|talk]]) 00:46, 27 June 2011 (UTC)
:According to [http://books.google.com/books?id=2rkHQpToi9sC&pg=PA582 this], "maximum reliably recorded adult lengths are in the 16-17 meter range". ~ [[User:Mesoderm|Mesoderm]] ([[User talk:Mesoderm|talk]]) 01:29, 27 June 2011 (UTC)

== life and reproduction ==

Would it be scientifically accurate to say that by having a child, I am perpetuating 3.5 billion years of successful reproduction, and therefore extending a 3.5 billion year long lineage by one generation? [[User:The Masked Booby|The Masked Booby]] ([[User talk:The Masked Booby|talk]]) 02:49, 27 June 2011 (UTC)
:That's probably roughly right, although the lineage conceivably might have been a lot longer than that if life on Earth started here via [[panspermia|exogenesis]]. Note that in any event, exactly how many [[generation]]s it took to create you isn't precisely defined, because sexual reproduction can mix the genes of individuals of widely different ages. There's presumably also a little vagueness in the generation count due to it being a little vague as to when during the process of [[abiogenesis]] there began existing clearly defined [[cell]]s, with clearly defined parent cells. However, the vast majority of generations of your ancestors since life began involved asexual reproduction of single-celled organisms, so the vagueness in the number of generations wouldn't be that large of a percentage. [[User:Red Act|Red Act]] ([[User talk:Red Act|talk]]) 03:57, 27 June 2011 (UTC)
::The simple answer is "Yes". Now, if the OP is trying to figure out how many generations that translates to, it gets slipperier. Just among my own 16 great-great-grandparents, there is 37-year gap from oldest to youngest. That's more than the average length of a "generation" (20-30 years) just by itself. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 04:24, 27 June 2011 (UTC)
:::Actually more than one: your [[mitochondria]] have their own proud parentage. But if we credit that, we should also consider [[horizontal gene transfer]] which, in a sense, means that we could have parentage through many small bits of many different microbes in the billions of years past - before at last converging on some common ancestor(s) of all life in yet earlier generations. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 04:30, 27 June 2011 (UTC)
::::A microbe called Adam? :) ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 04:43, 27 June 2011 (UTC)

== Rock-hard stools and fake fruit juice ==

As a child I learned by experience that drinking too much fake fruit juice led to terrible stools so rock-hard I could only pass them by pulling them out piece by piece with my fingers. So I've long since avoided anything but real fruit juice - though on two or three occasions at hotels or social events I've forgotten this precept until unpleasantly reminded that it still applies even as an adult. But looking over the web it seems like fruit juice is commonly ''recommended'' to people with [[fecal impaction]] (which sounds like a more serious version of this), and it seems like advertisements for [[stool softener]]s have grown very common in the U.S. in recent years. <small>(the effect of home budget cutbacks...?)</small> So in the interest of all the kids who haven't learned by trial and error yet I'm curious - can someone think of evidence that might link this problem to some ingredient in fake fruit juice? The first guess that comes to mind is high fructose corn syrup... yet I get exposed to so much of that in other forms without any similar effect ever happening. Unfortunately, because of when and how I was exposed, I don't know the ingredients of the products involved, though one of the worst culprits vaguely resembled orange juice. I couldn't find anything on PubMed in a few basic searches... but I'm not sure what I'm looking for. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 05:56, 27 June 2011 (UTC)

:<small>For making that discovery I'd like to shake your hand ... or maybe not. :-) [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 06:23, 27 June 2011 (UTC)</small>

:But, seriously, if everyone who drank such drinks had that reaction, it would be widely known already. You must have had an allergy or unusual reaction. Also, I would bet that parents who give their kids fake juice also don't tend to give them enough fiber and provide a generally poor diet, overall, so any of those factors could contribute. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 06:23, 27 June 2011 (UTC)

::I don't see anything on PubMed about allergy causing fecal impaction. While it may not be a universal reaction I somehow doubt it's all that rare, judging by the prevalence of hard stools. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 06:31, 27 June 2011 (UTC)

:As a past participant in the F-plan diet, I can tell you that juicing oranges removes the fibre from them and leaves you with the water and other bits. If you want to get the benefit of the orange you need to eat the whole flesh (OK you can leave as much as the white pith as you wish to) and not to juice it. So real fruit juice could have the same effect, particularly if you're not drinking a great deal anyway.--[[User:TammyMoet|TammyMoet]] ([[User talk:TammyMoet|talk]]) 12:36, 27 June 2011 (UTC)

::Interesting. When I get real orange, grape, or apple juice, it's not uncommon for me to run through 1-2 liters in 24 hours, but it never caused this effect. But I'm getting the impression the underlying biology is more variable than I thought. Frankly, I'd been thinking that the reaction ''might'' be universal and widely known, since after all there are things like [[olestra]] (and I think adulterated [[olive oil]]...) which are widely sold and which have equally disturbing effects. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 15:04, 27 June 2011 (UTC)

== WIMPs ==

There is a huge amount of conjecture and speculation about [[weakly interacting massive particle]]s in the literature, going back to [[mirror matter]] hypotheses in the 1950s. Has there ever been any evidence for their actual existence? [[Special:Contributions/76.254.22.47|76.254.22.47]] ([[User talk:76.254.22.47|talk]]) 07:13, 27 June 2011 (UTC)
:Have you read [[Weakly interacting massive particles#Experimental detection]]? [[User:Red Act|Red Act]] ([[User talk:Red Act|talk]]) 07:21, 27 June 2011 (UTC)
:[[Neutrinos]] are WIMPs so the answer is yes! But so far no smoking gun evidence for other kinds of WIMPs has been found. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 07:54, 27 June 2011 (UTC)
::That's not true and the Wiki-articles on this subject are out of date. The DAMA-Libra results which were originally received by a lot of scepticism have been confirmed by the COGENT results, and very recently COGENT has also reported an annual modulation. These are consistent with light WIMPS of a mass of about 8 GeV to which other DM direct detection experiments are not sensitive to. There are a lot more physicists taking these results serious than a few years ago. Because you first had the DAMA results, then the confirmation of these results by DAMA-Libra and then later the completely independent experiment COGENT. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 15:08, 27 June 2011 (UTC)
:::Thanks for that information. I had heard of the DAMA results but wasn't too impressed. I will definably look into the COGENT experiment which I hadn't heard of before. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 16:28, 27 June 2011 (UTC)
:::After reading about CoGeNT (Which seems to be part of the [[CDMS]] II experiment), I have to say that I don't think that is the smoking gun evidence just quite yet, though we may be getting tantalizingly close to it. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 19:01, 27 June 2011 (UTC)

== Difference between curd and yoghurt ==

difference between curd and yoghurt... their nature and formation..... acidic nature.... <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Simplyds|Simplyds]] ([[User talk:Simplyds|talk]] • [[Special:Contributions/Simplyds|contribs]]) 12:13, 27 June 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->
:: Have you read the Wikipedia articles on [[curd]] and [[yoghurt]]? The differences are easy to discover. Oddly, the acidity of these foodstuffs seems harder to determine. After a bit of a look round I found [http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2621.1983.tb14839.x/abstract?systemMessage=Wiley+Online+Library+will+be+disrupted+2+July+from+10-12+BST+for+monthly+maintenance this] which is a bit heavy but has info on yoghurt, and [http://manageyourheartburn.com/food-acidity.php?foodid=263 this one] has info on milk curd. [[User:Richard Avery|Richard Avery]] ([[User talk:Richard Avery|talk]]) 12:55, 27 June 2011 (UTC)

== Capturing CO2 ==

Could the CO2 expelled by a car be captured? [[User:Wikiweek|Wikiweek]] ([[User talk:Wikiweek|talk]]) 12:18, 27 June 2011 (UTC)

:Sure, by attaching a hose to the exhaust pipe and routing it somewhere. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 12:57, 27 June 2011 (UTC)

:: Yes Buggs, I'm thinkin' the "somewhere" leaves your response a bit open-ended, and not even clever. [[User:Caesar&#39;s Daddy|Caesar&#39;s Daddy]] ([[User talk:Caesar&#39;s Daddy|talk]]) 13:13, 27 June 2011 (UTC)

::::I've seen this done in garages, when the mechanics have to run the engine for awhile to test something. The hoses presumably route the CO, CO2, soot, and whatever else, to the outside of the building. Given that, it ought to be possible to capture it. Although, as noted, it's not "pure" CO2 emitting from a car, but a variety of things. So it might be possible to capture the contents of the exhaust, but by what process would you separate the various products from each other? ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 13:37, 27 June 2011 (UTC)

:::Somewhere to a CO2 parallel universe, where it disappears? But would it be practical? You'll still need some way of compressing it... <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Wikiweek|Wikiweek]] ([[User talk:Wikiweek|talk]] • [[Special:Contributions/Wikiweek|contribs]]) 13:14, 27 June 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->

::::You can bubble the CO2 through [[lime water]] which sequesters it as [[Calcium carbonate]]. This is a simple kind of [[carbon dioxide scrubber]] which I will let people read and follow links from on their own time. Attaching such systems to cars, however, is impractical and expensive, which is why it isn't done. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 18:30, 27 June 2011 (UTC)

:::::Several by-products of combustion are already captured in a [[catalytic converter]], but CO2 is not one of them because out of all the by-products, CO2 is one of the least harmful. [[User:Vespine|Vespine]] ([[User talk:Vespine|talk]]) 00:42, 28 June 2011 (UTC)

::::::Catalytic converters work by reducing nitrogen and sulfur oxides to less harmful gasses. Such oxides make up a miniscule amount of the exhaust, which is still mostly carbon dioxide; so to deal with the CO2 would require a MUCH larger system. Furthermore, the primary danger of CO2 is as a greenhouse gas, and its not clear that a reduced product (in this case likely methane, CH4) would be any less harmful. The problem with carbon sequestration in calcium carbonate is that you have to, very frequently, change out the chalk and replace the lime. Quite messy business for something you want to just "work" without any outside help, like a catalytic converter does. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 02:55, 28 June 2011 (UTC)

::::::Note that a catalytic converter does not 'capture' anything. As the name implies, it contains one or more large-surface-area [[catalyst]]s that encourage the conversion of certain exhaust components into less-noxious chemicals. (This generally includes the combustion of unburned or partially-burned fuel, the oxidation of [[carbon monoxide]] into less-toxic [[carbon dioxide]], and the breakdown of [[nitrogen oxide]]s into nitrogen and oxygen.) [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 14:56, 28 June 2011 (UTC)

:It's not very practical to capture the carbon dioxide from the tailpipe as the car is being driven down the street, for the reasons listed above. A more practical approach may be to use [[carbon credits]] and [[carbon trading]]. Under such a system, anyone driving (or perhaps manufacturing or selling) a car would have to pay a company to extract the equivalent amount of carbon dioxide from the air and sequester it. This approach has the possibility of being far more efficient, but requires the political will to pass the legislation to make it mandatory. I believe there are companies which will currently do this on a voluntary basis, but, of course, most drivers won't participate. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 17:29, 28 June 2011 (UTC)

== [[General Fusion]] ==

What are the main reasons it will fail? [[Special:Contributions/20.137.18.50|20.137.18.50]] ([[User talk:20.137.18.50|talk]]) 12:33, 27 June 2011 (UTC)

:Well, it might fail to solve some of the technological challenges required to make fusion happen in the first place. Or it might achieve a repeatable fusion reaction that consumes more energy than it releases. Or it might solve all those problems, but still not be an economically feasible process. [[User:Gandalf61|Gandalf61]] ([[User talk:Gandalf61|talk]]) 12:49, 27 June 2011 (UTC)

:Private companies based on fusion have failed in the past because the capital R&D costs are very high and the guarantee of economical success is nonexistent. They have an additional downside from government or university work in that they are reliant on investment funds but they are trying to develop proprietary technology. So generally they need hype but have difficulty providing the details about how they made it happen, which is a sure recipe for suspicion. There was an ICF company in the early 1970s that failed after cycles of this sort — it turned out that ICF was hard, and that generating sustained research funds from private donors was hard. Universities and governments have typically dominated in this field because their funding mechanisms are not profit-based. You can still get useful results even if you don't get closer to getting a profit in those contexts, but that is not a good business model.
:This is a separate question from the specific technical one. The general difficulty with fusion is that the tolerances for imperfections (either in keeping the plasma off of the walls in MCF, or compressing it in ICF) are very low, for any imperfection rapidly leads to either incredible inefficiency or rapid cooling, both of which make generating a gain in net energy unlikely. Now I don't know much about [[Magnetized target fusion]] but it seems to be an attempt to average out the difficulties of both. Whether it actually works to that end, or whether it simply means you are trying to solve two different and difficult problems at the same time, remains to be seen, I think. The track record for fusion is not great: every problem solved usually results in the discovery of two more problems. This is why the two current most favored efforts (NIF and ITER) are basically based on the idea of scaling it up to monstrous sizes so that hopefully the imperfections become less important. --[[User:Mr.98|Mr.98]] ([[User talk:Mr.98|talk]]) 13:52, 27 June 2011 (UTC)
:I don't like your ''will'' there. That's very pessimisitic. It could fail, for a variety of reasons from physics to politics, but that's far from certain. [[User:Ikanreed|i kan reed]] ([[User talk:Ikanreed|talk]]) 17:05, 28 June 2011 (UTC)

::I think the OP is just expressing the fact that so far every attempt at commercializing fusion (much less getting even net energy) has failed over the past five decades. There are little reasons to be optimistic with fusion — the history of fusion research is filled with people saying "this shouldn't be too hard — give us 5 years!" again and again and again and again. It turns out that controlled fusion is genuinely ''hard''. --[[User:Mr.98|Mr.98]] ([[User talk:Mr.98|talk]]) 18:44, 28 June 2011 (UTC)

:::<small>What's so hard about putting a star in a bottle ? :-) [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 19:13, 28 June 2011 (UTC) </small>

:::Five years? Everyone knows commercial fusion power is twenty years away -- and has been for the past half-century. --[[User:Carnildo|Carnildo]] ([[User talk:Carnildo|talk]]) 00:40, 29 June 2011 (UTC)

::::University/lab scientists say 20 years. People wanting to commercialize it say 5 years. Which is a nice reflection of the different funding forces playing on both of them — one says "fund more basic research and you'll get this cool technology," the other says, "invest today, earn money soon!" --[[User:Mr.98|Mr.98]] ([[User talk:Mr.98|talk]]) 00:44, 29 June 2011 (UTC)

== bond angles ==

how "flexible" are bond angles (or equilibrium bond angles, because they can move)? I mean in large molecules like polymers, they can easily bend (such as polyethylene) and we see a lot of images showing structures like DNA bending as if its a simple rope or something.also, the covalent bonds in liquid glasses such as SiO sre still present but apear to be somehow looser than the solid form.. if the bond angles (or equilibrium bond angles) are more flexible when the olecules are larger,why is it that way. is everything about molecular geometry only true for smaller molecules? thanks.--[[User:Irrational number|Irrational number]] ([[User talk:Irrational number|talk]]) 12:44, 27 June 2011 (UTC)

:* Some bonds are free to move as a swivel. allowing large molecules to bend.
:* Large molecules have many bonds. The slight flexibility of each of them can add up to a large flexibility for the larger molecule.
: [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 17:14, 27 June 2011 (UTC)
Do these materials(large molecules) naturaly tend to bend too?-[[User:Irrational number|Irrational number]] ([[User talk:Irrational number|talk]]) 18:26, 27 June 2011 (UTC)

::There are two conflicting things here. First, a long simple [[alkane]] is indeed very floppy, and bends quite alot. However, that bending only works if the molecule is dimensionally constrained; essentially long straight chains are the "floppiest". When there is a network of bonding within a molecule in three dimensions, it can constrain the bonding. The carbons in an alkane are in the same [[hybrid orbitals|hybridization]] as the carbons in [[diamond]], and yet diamond is very much NOT flexible. In DNA, the three-dimensional structure constrains the DNA chain into a relatively rigid double helix, though the entire chain does have some flex to it. Look at other [[macromolecule]]s like proteins. Some proteins are very flexible, while others are not. The difference is the presence of large numbers of [[cysteine]] bases, which form [[disulfide bond]]s and constrain the structure of the protein; proteins with lots of disulfide crosslinking (like [[keratin]]) tend to be relatively inflexible. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 18:28, 27 June 2011 (UTC)

:::There are [[cubane]], [[propellane]]s, [[cyclobutane]] at 90 degrees ... even [[cyclopropane]] at 60 degrees. It's hard to think of a molecule that forces C-C bonds at a smaller angle than that, but if you do ... odds are someone's done research on it. ;) The bonds have a preferred angle, yes, but generally carbons seem to prefer association of any sort over none at all. But the strain on such structures is enormous - of course, in a long piece of plastic, the deformation of any ''one'' bond is absolutely miniscule by comparison. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 18:46, 27 June 2011 (UTC)

== how did biblical figures probably walk on water ==

if not by magic, then what is the most likely mechanism biblical figures used to walk on water? <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/188.29.96.144|188.29.96.144]] ([[User talk:188.29.96.144|talk]]) 13:38, 27 June 2011 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->

:There is not universal agreement that Jesus was literally walkig on the water. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 13:40, 27 June 2011 (UTC)

::They probably didn't... [[User:AndyTheGrump|AndyTheGrump]] ([[User talk:AndyTheGrump|talk]]) 13:42, 27 June 2011 (UTC)

:::The could have used floating sandals, as in the illustration in our article on [[Walking on water]].--[[User:Shantavira|Shantavira]]|[[User talk:Shantavira|<sup>feed me</sup>]] 13:49, 27 June 2011 (UTC)

::The article [[Jesus' walk on water]] gets into specifics of the Bible story. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 13:52, 27 June 2011 (UTC)

:I think Jesus walked on water using the same levitation mechanism by which [[Yoda]] levitated, i.e., the levitation was enabled by the imagination of the storyteller. But see [[levitation]] for real levitation mechanisms, and [[levitation (paranormal)]] for other mythological levitation. [[User:Red Act|Red Act]] ([[User talk:Red Act|talk]]) 14:08, 27 June 2011 (UTC)

::A [[sandbar]] close to the surface of the water could give the appearance of walking on water especially if seen from another water-going vessel—perhaps at a distance, and perhaps with the lower portion of the body blocked from view by the water-going vessel upon which one finds oneself. [[User:Bus stop|Bus stop]] ([[User talk:Bus stop|talk]]) 19:37, 27 June 2011 (UTC)

::: Maybe they thought [[Being There | life is a state of mind]]. [[User:Richard Avery|Richard Avery]] ([[User talk:Richard Avery|talk]]) 19:48, 27 June 2011 (UTC)

:Modern magicians use a clear plastic support, just below the water. Plastic wasn't available then, so perhaps glass was used. Unlike the sandbar, this can fool people right there, as clear objects can become virtually invisible, once submerged, especially with waves at the top. Also note that in Biblical times it was common for religious figures to use magic tricks to convince people they had God(s) on their side. The magic contest between [[Moses]] and the Egyptian high priest, where each turned their staff into snake(s), shows this nicely (some Christian fundamentalists might argue that Moses' trick was the real thing, but who argues that the Egyptian priest was really using the power of Egyptian gods ?). [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 19:54, 27 June 2011 (UTC)

:::You have to be careful with that trick. The nature of waves in shallow water is different from deeper water. In ''Superman II'' there was a scene that showed the evil General Zod walking on water. They got a little too close with the camera, and although you couldn't see the platform he was walking on, you could see its ''effect'' in the rippling of the water. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 23:39, 27 June 2011 (UTC)

::::<small>But, of course, you were merely seeing the effect on the waves from the supporting force field. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 04:21, 28 June 2011 (UTC) </small>

::Egyptian fundamentalists of course. If Wikipedia had been around in Old Testament times, there might have been a heated debate. [[User:Wanderer57|Wanderer57]] ([[User talk:Wanderer57|talk]]) 21:28, 27 June 2011 (UTC)

:::If the internet had been around in O.T. times, God would simply have posted the Ten Commandments in His blog. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 23:35, 27 June 2011 (UTC)

::::<small>If it was a wiki, I'd hate to think of all the edit wars on that one. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 04:21, 28 June 2011 (UTC) </small>
:::::<small>He would probably have added "Thou shalt not annoy others with your constant twittering." [[User:Googlemeister|Googlemeister]] ([[User talk:Googlemeister|talk]]) 13:21, 28 June 2011 (UTC) </small>
::::::<small>And his Admin policy would have been strict. "[[Disemvoweling|Disemvowellement]]? No, I think you [[Disembowelment|misheard]]." {The poster formerly known as 87.81.230.195} [[Special:Contributions/90.201.110.117|90.201.110.117]] ([[User talk:90.201.110.117|talk]]) 17:18, 28 June 2011 (UTC)</small>

== painkillers for waxing ==

What would be more effective pain relief for waxing of intimate areas? Paracodal or ibuprofen? I've been advised to take something before my appt and these are the two options in my drawer! Thanks. (just so you know, I take both occasionally and am not allergic to either and have never had any adverse reactions in the past and this is not a request for "medical advice", you can just give me science!) [[Special:Contributions/195.27.52.146|195.27.52.146]] ([[User talk:195.27.52.146|talk]]) 15:15, 27 June 2011 (UTC)

:It really ''is'' a request for medical advice, actually. Who advised you? In many countries only a medical practitioner would be able to advise. In others, perhaps a pharmacist. [[User:Itsmejudith|Itsmejudith]] ([[User talk:Itsmejudith|talk]]) 15:51, 27 June 2011 (UTC)

:I feel that this is a specific question about the action of the two drugs. In this case, there is a very clear answer. Ibuprofen primarily reduces inflammation and fever. Neither of those will be of much help in reducing upcoming pain in sensitive nerve endings. Paracodal contains paracetamol, which specifically reduces pain by reducing the sensitivity of nerve endings. Both are "pain relievers", but they relieve different kinds of pain. If this doesn't completely answer the question, please delete it and mark this as a true request for medical advice. -- [[User:Kainaw|<font color='#ff0000'>k</font><font color='#cc0033'>a</font><font color='#990066'>i</font><font color='#660099'>n</font><font color='#3300cc'>a</font><font color='#0000ff'>w</font>]][[User talk:Kainaw|&trade;]] 18:41, 27 June 2011 (UTC)

::This sounds like a request for medical advice to me. I have no idea, for example, whether the practitioner might be relying on your yelps and screams as feedback about whether he/she is pulling too hard, and by suppressing them you could make something gruesome happen. IMHO if something is so painful you need a drug to suppress the pain, your body is trying to gently hint to you that perhaps it is not a good idea. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 18:50, 27 June 2011 (UTC)

:I don't think you need a medical license to suggest cosmetics, so I would go with a skin cream or shaving cream containing [[menthol]] and/or [[eucalyptus]] and/or [[aloe]]. The menthol a pain-killer, the eucalyptus is an antiseptic to prevent infection, and the aloe is a painkiller and will help you heal after. The advantage of a topical cream is that it's much stronger where you need it, while anything you take orally is distributed around your body, so very little of it will actually go to the skin in question. I do agree with Wnt, though, that if they advise stronger painkillers, they aren't doing it right. It shouldn't be that painful. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 20:08, 27 June 2011 (UTC)

:Why not use [[Lidocaine/prilocaine]]?

:<blockquote>The lidocaine/prilocaine combination is indicated for dermal anaesthesia. Specifically it is applied to prevent pain associated with intravenous catheter insertion, blood sampling, superficial surgical procedures; and topical anaesthesia of leg ulcers for cleansing or debridement.[3] Also, it can be used to numb the skin before tattooing as well as laser hair removal.</blockquote> [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 22:32, 27 June 2011 (UTC)

::Kainaw is right, that's just what I wanted to know. To the rest, waxing is notoriously painful and taking a couple of painkillers before doing it is pretty much standard advice from the practitioners. Wnt—there's no such thing as "pulling too hard" when it comes to waxing! That's the whole point. :) Thanks for all the responses! [[Special:Contributions/195.27.52.146|195.27.52.146]] ([[User talk:195.27.52.146|talk]]) 06:44, 28 June 2011 (UTC)

== communication over vast distances ==

Is it in any way possibly to send information over vast distances (in a reasonable amount of time). Even better, is this also applicable to traveling? [[Special:Contributions/66.229.227.191|66.229.227.191]] ([[User talk:66.229.227.191|talk]]) 15:19, 27 June 2011 (UTC)
::: The question is vague. By typing this comment, I'm sending information to people in distant countries, if they happen to be looking at this page. By using my cell phone, I can talk to those people. Did you mean vaster or faster than that? [[User:Michael Hardy|Michael Hardy]] ([[User talk:Michael Hardy|talk]]) 20:43, 27 June 2011 (UTC)
:No form of communication or transportation is faster than the [[speed of light]], which severely limits [[interstellar travel]]. [[User:Red Act|Red Act]] ([[User talk:Red Act|talk]]) 15:39, 27 June 2011 (UTC)
:A [[wormhole]] would be useful but there is no reason to believe that they actually exist. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 17:19, 27 June 2011 (UTC)
:The speed of light is fast enough if you transmit yourself using the message. Ultimately, we are just information stored in the brain and all that can in principle be transmitted. If the message that defines you travels 10,000 light years and upon arrival you are recreated using the received message, you would not experience the 10,000 years. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 17:32, 27 June 2011 (UTC)
::You wouldn't experience ''anything.'' If such technology existed, allowing a copy of a human brain's "state" to exist, it would be reasonable to describe it as a [[Fork (operating system)|<tt>fork()</tt>]]. A copy of the state would be created and begin new processing. But it does not change the processing-state of the original copy. Needless to say, hypothetical technology to serialize the complete state of a human brain, transmit it by any method, and restore functionality by running it on a "virtual machine" is still science-fiction. Much work remains to precisely ''define'' the type of "machine" and its "instruction set" or "state." Even once these tasks are complete, building a replica and designing a "scanner/copier" will be additional, complex tasks. [[User:Nimur|Nimur]] ([[User talk:Nimur|talk]]) 17:43, 27 June 2011 (UTC)
::Add to that the fact that you would only be able to travel to places that have a receiver. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 19:28, 27 June 2011 (UTC)
:::If it takes 10,000 years to get there, they might have a receiver built by then. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 23:33, 27 June 2011 (UTC)
::::Indeed, so if e.g. the Earth were to face some disaster, we could transmit signals that contain the information to recreate our civilization elsewhere. That would be easy to do if we have transformed to a machine civilization. If the signal is powerful enought it can be picked up millions of lightyears away in some nearby galaxy. They can then download our programs and eventually our entire civilization can be rebuilt there.
::::A limiting factor here is the data rate. Perhaps the best strategy is to have a radio beacon repeatedly transmitting an easy to decode message that tells listeners to look out for a laser beam. Using a visible light laser, one can transmit more than 10^14 bits/second. So, more than 10^21 bits of information can be transmitted per year and if we use higher frequency beams much more than that.
::::The power of radio transmitter and the laser beam must be large, but that's not a problem for a machine civilization capable of using all the power that the Sun emits. The laser beam can be split into separate parts that are aimed at many of the nearby galaxies. The beam divergence can be made small enough such that the beam's width is exactly the size of the galaxy upon arrival (the brighness of the beam would then be similar to the apparent brighness of a star at a distance of the order of the diameter of that galaxy, so it would be easy to detect).
::::Our survival then depends on there being just one civilization capable and willing to recreate us among the many hundreds of nearby galaxies. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 00:16, 28 June 2011 (UTC)




:If light-speed communication is too slow for you then [[superluminal communication]] is the page to look at for more information. Apparently the prospects are not good. --[[User:Antiquary|Antiquary]] ([[User talk:Antiquary|talk]]) 19:21, 27 June 2011 (UTC)

== Biology ==

Why do some birds migrate even though they are warm blooded ? <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Ssmagic|Ssmagic]] ([[User talk:Ssmagic|talk]] • [[Special:Contributions/Ssmagic|contribs]]) 16:27, 27 June 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->

:It doesn't have anything to do whether an animal is warm blooded or cold blooded. Many species of all kinds migrate. See [[animal migration]] for details. --- [[User:Medical geneticist|Medical geneticist]] ([[User talk:Medical geneticist|talk]]) 16:32, 27 June 2011 (UTC)

:Humans are warm-blooded, but we still find it desirable to take many steps in order to avoid being cold. Why should it be any different for animals? There are many different adaptations to cold, including migration and [[hibernation]]. [[User:Dragons flight|Dragons flight]] ([[User talk:Dragons flight|talk]]) 17:01, 27 June 2011 (UTC)

::Humans [[Arizona|also]] [[Florida|migrate]], at least in their older years... --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 18:21, 27 June 2011 (UTC)

:Apart from seeking more comfortable temperatures, some bird species have to migrate because the availability of their preferred or obligatory food sources are greatly affected by the changing seasons. If, for example, a bird lives on insects, it would likely find very slim pickings during a Northern European winter, making migration to, say, North Africa, advantageous. Our article [[Bird migration]] describes in detail this and several other reasons for the phenomenon. {The poster formerly known as 87.81.230.195} [[Special:Contributions/90.197.66.204|90.197.66.204]] ([[User talk:90.197.66.204|talk]]) 19:46, 27 June 2011 (UTC)

:Another frequent reason for migration is reproduction. They often migrate from a wide area to a small one, where their greater population density helps them find a desirable mate. Then, there is sometimes "safety in numbers" where they raise the chicks, or perhaps they breed in an inaccessible area to deter predators. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 20:29, 27 June 2011 (UTC)

::In general, birds migrate because of the reasons above, not because it's cold. There are plenty of birds that hang around in winter when there's a food source. You might say the cold and snow are ''indirect'' reasons for the migration. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 23:31, 27 June 2011 (UTC)

:::I suppose you could argue that those species which migrate to warmer climates in winter never developed (or lost) the adaptations that would allow them to survive cold weather (right up to penguins that can survive winter in [[Antarctica]]). So, at this point, they do need to migrate to avoid the cold, among the other reasons. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 04:17, 28 June 2011 (UTC)

::::Penguins migrate to a degree too though, don't they? [[User:Googlemeister|Googlemeister]] ([[User talk:Googlemeister|talk]]) 18:35, 28 June 2011 (UTC)

::::::Yes, but for other reasons, not to stay warm. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:15, 28 June 2011 (UTC)

:::::<small>"The swallow may fly south for the winter, yet it is no stranger to our land..." [[User:Albval|Albval]] ([[User talk:Albval|talk]]) 19:36, 28 June 2011 (UTC)</small>

::::::Be amazed by the journeys of the [[arctic tern]], typically about 2 million km in a lifetime, commuting from the arctic to the antarctic. [[User:Mikenorton|Mikenorton]] ([[User talk:Mikenorton|talk]]) 19:45, 28 June 2011 (UTC)

== hello (identifying #7 plastic) ==

how do they tell #7 plastics apart at recycling centers <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Tsp12345|Tsp12345]] ([[User talk:Tsp12345|talk]] • [[Special:Contributions/Tsp12345|contribs]]) 19:38, 27 June 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->

: That's a good question. The [[plastic recycling]] article is rather hazy on the subject, simply saying that they're separated based on their [[resin identification code]]. [http://www.lotfi.net/recycle/plastic.html This article] says the manual sorting process is too expensive and isn't sufficiently reliable, and talks about two technologies that can identify some plastic types. It's not clear if these automatic methods are in widespread use. In my own area, it seems they only want drinks bottles; everything else (tubs, trays, lids, caps, films, bags, etc.) they don't take. I imagine that if (or when) most retail products contain [[RFID]] tags, the separation of some post-consumer waste (bottles, tubs, trays at least) may become more easily automated. -- [[User:Finlay McWalter|Finlay McWalter]] ☻ [[User talk:Finlay McWalter|Talk]] 19:51, 27 June 2011 (UTC)

::Some recycling programs will only accept properly marked (i.e. with the correct code) plastics for recycling. Some plastics, if kept with the same type, can be melted down and reused in the same application; however this requires proper sorting. While "pure" plastics can fetch greater prices on resale, they are also much more labor intensive to ensure proper purity; some cheaper reuses (for example, shredded and used as [[mulch]]) fetch much less on the open market, but then again are much cheaper to process. [[Plastic recycling]] has more information, and the economics of recycling are quite complex, especially when coupled with the "social pressures" to recycle even when it is not financially feasible to do so. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 20:22, 27 June 2011 (UTC)

:<small>I added to the title to make it actually useful. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 20:25, 27 June 2011 (UTC)</small>
:I found a few sources via Google Books. Several of them say that Near Infrared (NIR) and Middle Infrared (MIR) spectroscopy can be used with some success, but that it doesn't work with plastics that have black/grey dyes in them, because those absorb the NIR wavelength; also MIR cannot be used for high-speed processing.[http://books.google.com/books?id=QjVI7IrqtcQC&pg=PA198][http://books.google.com/books?id=TBrOGJqvgcMC&pg=PA113][http://books.google.com/books?id=KZCNJ8qSWKYC&pg=PA584][http://books.google.com/books?id=HQ6ZniMlUP4C&pg=PA346] Other techiniques measure the density or melting point, or use chemical markers.[http://books.google.com/books?id=s8cp8TwfWIsC&pg=PA254][http://books.google.com/books?id=HQ6ZniMlUP4C&pg=PA346]] ... Anyways, I would suggest searching Google books for ''identifying plastics recycling'', and you'll probably turn up quite a bit more information. Cheers. ~ [[User:Mesoderm|Mesoderm]] ([[User talk:Mesoderm|talk]]) 20:36, 27 June 2011 (UTC)

== weird plastic taste in coffee ==

Hi, I'm a total coffee philistine, but one thing I can't handle is the plastic taste that you get from some containers. Basically I brew up several cups, and store them in my plastic container (Sistema brand, in Australia), but of late, I've noticed the ghastly plastic gunky taste is getting in the coffee, even though it didn't originally. I've been using them for several months without incident, and now, suddenly, nearly every coffee comes out awful. Why does this happen? Surely plastic is inert, so it shouldn't get into food. Has this problem ever been investigated with plastic containers? Also, is there any cure? [[User:It&#39;s Been Emotional|It&#39;s been emotional]] ([[User talk:It&#39;s Been Emotional|talk]]) 21:04, 27 June 2011 (UTC)

: I used to drink coffee out of various plastic and foam containers and noticed the same thing. Given that many plastics (or byproducts of burning/heating them) act as [[endocrine disruptors]] or [[mutagens]], I [[precautionary principle|didn't feel like taking any chances]] and started drinking out of ceramic, glass, or metallic containers. I no longer have to deal with the unpleasant plastic taste (which I notice ''every'' time I drink out of plastic containers now), and I don't have to worry about the health effects of drinking a hot liquid out of a plastic container. ~ [[User:Mesoderm|Mesoderm]] ([[User talk:Mesoderm|talk]]) 21:13, 27 June 2011 (UTC)

::I agree with glass (not leaded crystal) or ceramic (unpainted ceramic, that is). Metal, however, can also react with beverages, so they often coat this inside of metal containers with plastic to prevent this, and we're back to the original problem (unless you have a gold or platinum bottle :-) ). I use glass, myself. Specifically, I buy [[Everfresh]] juices and reuse the glass bottles: [http://www.everfreshjuice.com/Home.php]. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:32, 27 June 2011 (UTC)

:To answer your question, there are several chemicals that can leach out of plastic bottles into the contents. More leaching is expected with more heat, more flexing of the bottle, more time, and more acidic content (a highly alkaline drink might be a problem, too, but there aren't many of those). In your case, pouring hot coffee into it might be the problem. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:35, 27 June 2011 (UTC)

Thanks, very astute of you, StuRat. Thanks to all of you. [[User:It&#39;s Been Emotional|It&#39;s been emotional]] ([[User talk:It&#39;s Been Emotional|talk]]) 23:11, 27 June 2011 (UTC)

:Don't they have ceramic <s>[[coffee pot]]s</s> coffee pots in Australia? Or even [[teapot]]s? (I see that "coffee pot" re-directs to "Coffeemaker", which are of course not coffee pots. Coffee pots are similar to tea pots, but designed for coffee. Usually taller and more cylindrical than teapots in my experience). [[Special:Contributions/2.97.219.42|2.97.219.42]] ([[User talk:2.97.219.42|talk]]) 10:15, 28 June 2011 (UTC)

::In [[US English]], at least, a coffee pot (that's 2 words in US English) is the container into which the freshly brewed coffee pours from the coffee maker (also 2 words), and a tea pot (also 2 words) is where the tea is steeped. So, neither is the storage container asked about here. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 13:14, 28 June 2011 (UTC)

:::The US is not the whole wide world, and people often do things differently in different countries. [[Special:Contributions/92.29.120.26|92.29.120.26]] ([[User talk:92.29.120.26|talk]]) 20:28, 28 June 2011 (UTC)

::::And I never said that it was, did I ? If there's a country where a "coffee pot" (as 1 word or 2) or a "tea pot" (as 1 word or 2) are used for storage of beverages, then I'd like to know that. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 20:42, 28 June 2011 (UTC)

:::::Well, Britain, Europe, India, China, and many more. Cofffee pots are particularly used in Arabia I understand. Its called an "X"-pot because its got "X" in it. Perhaps you are confusing them with kettles, which are only used for heating water. [[Special:Contributions/92.29.120.26|92.29.120.26]] ([[User talk:92.29.120.26|talk]]) 21:04, 28 June 2011 (UTC)

:::::::No, I'm not confusing those. See below. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:13, 28 June 2011 (UTC)

::::::Typical UK coffee pots - [http://www.havens.co.uk/tableware/dinner-services/brand/wedgwood/type/coffee-pots/ here] '''[[User:Ronhjones|<span style="border:1px solid black;color:black; padding:1px;background:yellow"><font color="green">&nbsp;Ron<font color="red">h</font>jones&nbsp;</font></span>]]'''<sup>[[User talk:Ronhjones|&nbsp;(Talk)]]</sup> 21:28, 28 June 2011 (UTC)

:::::::That's what I'm thinking of. Those are for serving coffee, not for storing it. My reading of the Q is that they want to store the coffee, and possibly transport it to another location, and therefore need a container which can be sealed for that purpose, such as a [[thermos]]. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:10, 28 June 2011 (UTC)

== is it any easier to catch a bullet at the top of its arc if you throw it up than if you shoot it up? ==

If I take a bullet in my hand, and throw it up a couple of feet for you to catch, is it any easier for you to catch it than if we repeat the same thing, but, in a very still place, you happen to be on top of a cliff and the arc of the bullet I shoot from somewhere far far away looks, relative to you, exactly the same on paper as when I threw it up to you from a couple of feet below? I mean, because the top of the parabola should look the same. <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/188.28.68.234|188.28.68.234]] ([[User talk:188.28.68.234|talk]]) 22:10, 27 June 2011 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->

:From a pure physics standpoint, velocity is velocity; the round has no memory that it ''used'' to be going very fast; and so, near the top of a parabola, vertical velocity approaches zero. "Engineering details" may confound this simplistic viewpoint: a round fired from a gun will be ''hot''; it may be wobbling; it may have deformed during firing or flight. It will also be hard to aim very precisely due to [[error propagation]] (a longer time in flight means that tiny error in aim will result in large error in position). The safety factor should be considered, too - if you miscalculate, or if wind, non-ideal turbulence, or any other parameter changes the expected peak location of the trajectory, your experimenter will be in a very dangerous position. [[User:Nimur|Nimur]] ([[User talk:Nimur|talk]]) 22:18, 27 June 2011 (UTC)

::Well, the bullet still wouldn't be going very fast, even if your calcs are off a bit. However, the variability is enough that you couldn't reliably get the bullet to reach the peak of it's trajectory within reach of the target person on top of the cliff. So, it would be easier to catch if hand thrown. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:25, 27 June 2011 (UTC)

:Also if the bullet is shot out of a [[rifle]] it might be spinning pretty fast, which might make it harder to grab. [[User:Rckrone|Rckrone]] ([[User talk:Rckrone|talk]]) 23:15, 27 June 2011 (UTC)

::I think what the OP meant by "easier" is purely the act of nabbing the bullet, given that you just happen to be in the right place at the right time. At the very top of its arc, at least for one moment, it will have zero or near-zero vertical velocity, before it starts to fall again. So if you were next to the bullet and had a butterfly net or something, grabbing it should be just as "easy" as if it were thrown up in the air. Obviously, this only works if you've thrown or shot it pretty much straight-up. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 23:26, 27 June 2011 (UTC)

:::The difference that comes to my mind is that you couldn't see it if it originated at a distant point. In one instance you could maintain eye contact for the length of the trajectory. In the other instance you would only be able to establish eye contact at a fairly late point in its trajectory. This would introduce an added difficulty. Human vision is inadequate to the task of tracking a fast-moving small object especially at a considerable distance. While the object would still be small if tossed from only a few feet away, the tracking of such an object by the eyes of humans is still within normal operating range. [[User:Bus stop|Bus stop]] ([[User talk:Bus stop|talk]]) 23:33, 27 June 2011 (UTC)
::::You might, if it were painted international orange or something. Maybe the OP needs to clarify what he means by "easier". My concept of this would be that you could fly like Superman and be able to spot the bullet and to be at the top of the arc and grab it. However, Superman could grab it as soon as it leaves the rifle without doing himself any harm (unless it was made of kryptonite). So the OP needs to comment further. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 23:49, 27 June 2011 (UTC)

:Let's formulate this as a problem. Let's say we have a .38 Special, with a muzzle velocity of about 600 feet per second, which is pointed upward and fired. How accurately must the muzzle velocity and direction be controlled in order to produce an error of less than 1 foot in any direction in the location of the trajectory peak? Extra credit: how does the necessary directional accuracy compare to the maximum possible accuracy of a .38 Special? [[User:Looie496|Looie496]] ([[User talk:Looie496|talk]]) 23:49, 27 June 2011 (UTC)
::No one has specifically said it so I'll add it. Both bullets will be experiencing a constant downward acceleration of 9.8m/s<sup>2</sup> . So yes, the "top" of the parabola of the fired bullet will be identical to the parabola formed by a thrown bullet from the point where the thrown bullet's velocity matches that of the fired bullet. As stated above however, this is only given "perfect" conditions of no friction or turbulence (etc...) which of course don't exist in real life. [[User:Vespine|Vespine]] ([[User talk:Vespine|talk]]) 00:30, 28 June 2011 (UTC)
:::A bullet shot straight up will still travel a few thousand feet. If a bullet travels 5000 feet, then to be accurate to within 1 foot (assuming there is no wind or other atmoshperic effects) you will need accuracy of .01 degrees to be within a foot. I don't think most handguns would have that level of accuracy and even a sniper rifle would be tricky. Of course a sniper rifle would probably go a lot higher then 5000 feet since it has a much higher muzzle velocity. [[User:Googlemeister|Googlemeister]] ([[User talk:Googlemeister|talk]]) 13:13, 28 June 2011 (UTC)

== miami ==

do they have central heating in most houses in miami and what kind <small><span class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[User:Superhands99|Superhands99]] ([[User talk:Superhands99|talk]] • [[Special:Contributions/Superhands99|contribs]]) 22:40, 27 June 2011 (UTC)</span></small><!-- Template:Unsigned --> <!--Autosigned by SineBot-->

:It does get chilly enough in winter to need some form of heating, but, due to the relatively low amount of heating needed, electrical heating is common (the cost of electrical heating is prohibitive in colder climates). [[Radiator_%28heating%29#Electric_baseboard|Electric baseboard heating]] is one common form. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:56, 27 June 2011 (UTC)

::Miami recently set a record because 10 straight days failed to reach 65 F in January.[http://www.srh.noaa.gov/images/mfl/news/ColdEpisodeJan2010.pdf] I think little heating is required. Miami has a climate of 149 [[heating degree days]] versus Detroit (6224) or Duluth (9371). [[User:Rmhermen|Rmhermen]] ([[User talk:Rmhermen|talk]]) 00:58, 28 June 2011 (UTC)

::::Even 65°F is a bit cold, especially for the elderly. But, of course, those are the highs. The record low is 27°F: [http://www.weather.com/weather/wxclimatology/monthly/graph/USFL0316 (pick "Record Low" check box)]. At those temps you can die without some form of heat. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 04:10, 28 June 2011 (UTC)

:::It's my understanding that many homes in Miami area, especially the older ones, don't have heating systems. Presumably, on really cold days (by their standards), they use space-heaters or blankets or something. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 01:13, 28 June 2011 (UTC)

::::Or they could just use their aircos as heaters :) . [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 02:36, 28 June 2011 (UTC)

:::::That's right. I live in Florida (Not in Miami, though) and every house I've ever lived in has has a AC/heating unit, with one single exception. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 03:21, 28 June 2011 (UTC)
::::::By AC/heating unit do you mean [[Air source heat pumps]]? [[User:Rmhermen|Rmhermen]] ([[User talk:Rmhermen|talk]]) 21:19, 28 June 2011 (UTC)

= June 28 =

== Multiple sclerosis ==

What is meant by t1 or t2 lesion load?
how does it differ from active lesion? <span style="font-size: smaller;" class="autosigned">— Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/199.224.149.10|199.224.149.10]] ([[User talk:199.224.149.10|talk]]) 04:32, 28 June 2011 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot-->
:I can't give a detailed answer, but I can tell you that T1 and T2 are different ways of carrying out an [[NMR]] examination. [http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1692677/pdf/10603619.pdf This paper] describes them in detail, if you can make sense of it. [[User:Looie496|Looie496]] ([[User talk:Looie496|talk]]) 05:15, 28 June 2011 (UTC)
::To explain in better detail, see [[Magnetic_Resonance_Imaging#Basic_MRI_scans]]. T1 and T2 refer to two different MRI techniques (the MR in MRI is the same MR as in NMR and the terms (NMR and MRI) are occasionally used interchangably, though mostly NMR is reserved for the analytical chemistry technique, while MRI is used for the medical diagnostic technique. The authors of this paper are really refering to MRI). The technical details of each can be found in the article I cited, but for the purpose of the OPs question, and for the purpose of understanding that paper, the T1 and T2 lesion loads are merely the number of lesions detectable on a T1 scan versus a T2 scan. Each type of scan has different sensitivities, so they have different applications; some times you'll want to do a T1 scan and sometimes a T2 scan. The paper you cited is the results of various experiments to determine the ideal parameters for using MRI to detect multiple sclerosis lesions. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 05:27, 28 June 2011 (UTC)

== Colloquial medical expressions ==

When someone dies of a "hole in the heart", what did kill him?
And what about the classical - "dying of old age"? Does that simply mean "old person died, don't know why"? [[User:Wikiweek|Wikiweek]] ([[User talk:Wikiweek|talk]]) 14:39, 28 June 2011 (UTC)

: The former may often be [[ventricular septal defect]] -- [[User:Finlay McWalter|Finlay McWalter]] ☻ [[User talk:Finlay McWalter|Talk]] 14:43, 28 June 2011 (UTC)

:: Or an [[atrial septal defect]]. In a society with current medical care it would be unlikely for an adult to die of any kind of septal defect, since it would usually be repaired before significant hemodynamic consequences developed; a very large or complicated septal defect in an infant could cause death. --- [[User:Medical geneticist|Medical geneticist]] ([[User talk:Medical geneticist|talk]]) 22:04, 28 June 2011 (UTC)

:From [[Death_by_natural_causes]]: "Old age is not a scientifically recognized cause of death; there is always a more direct cause although it may be unknown in certain cases and could be one of a number of aging-associated diseases." [[User:SemanticMantis|SemanticMantis]] ([[User talk:SemanticMantis|talk]]) 14:49, 28 June 2011 (UTC)

:In the case of a "hole in the heart" due to injury, as in a bullet wound, it might be in any part of the heart, or perhaps nearby, say in the [[aorta]] or [[vena cava]]. In this case the victim is likely to [[hemorrhage]] to death, with the loss of blood pressure probably actually causing brain death. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 16:19, 28 June 2011 (UTC)

== Quantum superposition ==

Hello,

How does [[quantum superposition]] fit in with the [[principle of contradiction]]? It seems like QS can allow for a statement and its negation to be jointly true (i.e., "Schrödinger's cat is dead" and "Schrödinger's cat is alive" are both true at the same time). Does this mean the principle of contradiction is wrong?

Thank you. [[User:Leptictidium|Leptictidium]] (''[[User talk:Leptictidium|mt]]'') 15:09, 28 June 2011 (UTC)

:The principle of contradiction is logically sound. What is not clear is what is meant when you state that the cat is alive or that it is dead. Are those two states truly logic opposites to each other? QM says that these statements are not the logic negation of each other since a third state is also possible, namely the cat might be in quantum superposition state. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 15:34, 28 June 2011 (UTC)

::But QS is not a state in and as of itself, it's merely a superposition of states, right? [[User:Leptictidium|Leptictidium]] (''[[User talk:Leptictidium|mt]]'') 15:36, 28 June 2011 (UTC)

:::No, it is really a real state. If |a> and |b> are two orthonormal states, then so are |a'> = 1/sqrt(2) [|a> + |b>] and |b'> = 1/sqrt(2) [|a> - |b>]. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 15:40, 28 June 2011 (UTC)

::::Quantum mechanics makes a clear, definitional distinction between the ''state'' of the system, and the ''observable'' state of the system. We have an article on this concept: [[observable]]. Something that is still a superposition of states is not observable. When you ''measure'' the state, you are ''observing'' one of many possible states. [[User:Nimur|Nimur]] ([[User talk:Nimur|talk]]) 15:45, 28 June 2011 (UTC)
:::::Sorry, but that's plain nonsense. You can transform any observable using any arbitrary unitary transform to yield another observable. That such observables (whose eigenstatstes are superpositions of the previous ones) can't in practice be measured is not an issue, in principle you can measure a cat in a superposition of being dead and alive. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 17:40, 28 June 2011 (UTC)

:::::Therefore, no truly logic opposites can exist, since there will always be a third state possible. Yes? --[[User:Leptictidium|Leptictidium]] (''[[User talk:Leptictidium|mt]]'') 15:57, 28 June 2011 (UTC)
:::::: No. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 17:41, 28 June 2011 (UTC)


::::::Logic opposites are possible but the opposite of an electron with spin up is NOT an electron with spin down. The logis opposite of an electron in a spin up state is an electron that is not in a spin up state but could conceivably be in a superposition of states between spin up and spin down. A familiar example might help. The logic opposite of moving northward is NOT moving southward. That opposite would be not moving northward which might mean you are moving northwestward. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 16:30, 28 June 2011 (UTC)

::::::I prefer to phrase it this way. For example, let's take electron spin in the hydrogen atom. It can either take the value +1/2 or -1/2. When it is not measured, I do not say, "the particle is both spinning with +1/2 and -1/2." Instead, I phrase it as "the particle's spin is not measured. Here are the probabilities that it may be +1/2: (math); and that it may be -1/2: (math)." I think this simple choice of phrase makes quantum mechanics seem a lot less ''silly.'' But, if you want to say "the particle is both spinning up and not spinning up," (or, "the cat is both alive and dead"), you can very well phrase it that way. It's still silly. [[User:Nimur|Nimur]] ([[User talk:Nimur|talk]]) 16:08, 28 June 2011 (UTC)
:::::::Who said QM is not supposed to sound silly? If the electron is in a quantum superposition of a spin up and a spin down state than it is truly both at the same time. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 16:15, 28 June 2011 (UTC)
:You guys are all basing your statements on only one of the many possible [[Interpretations of quantum mechanics]], specifically the common [[Copenhagen interpretation]], which deals with such things as things existing in multiple states simultaneously, and with observation causing "collapse of the wavefunction" to produce the result; that is that the observation itself causes the result, somewhat non-mechanisticly. There are other, perhaps equally valid interpretations, such as the [[Ensemble interpretation]], which takes a more agnostic view on the connection between quantum mechanics and reality. The mental gymnastics which is sometimes required (such as our simultaneously alive-and-dead cat) to make the Copenhagen interpretation work is philosophically unsatisfying. It is perhaps really much better to just state that our knowledge of the cat's living/dead state is incomplete without observation. In any instant, it may be alive or it may be dead, but it will be definately one or the other of them, irrespective of our observation. What changes is which variables we feed into our equations to decide if it is alive or dead; once we observe the cat. The distinction is deciding whether or not the event occurs ''only at the moment of observation'' or ''at some impossible-to-determine time before the observation''. While philosophically the second proposition feels better, the first proposition actually makes the mathematics much simpler, since it gives us a specific point in time to determine when the "event" occurs; since it doesn't actually matter "when" prior to our observation, and since it is literally impossible to know "when" without observing it (i.e. you literally cannot determine the living/dead state of the unobserved cat unambigously from first principles, you can ONLY determine it empirically via observation), the first proposition works better for the purposes of making the math work. The end result is it doesn't really matter (from a scientific point of view) which "interpretation" works better for you, philosophically (that's why these are "interpretations" and not theories or laws or models, they don't require rigourous proof), the equations yield the same results either way, which is just the probability of the cat being dead as a function of time, and nothing more. What quantum mechanics does is destroy our belief in the "clockwork universe", that somehow given a perfect knowledge of initial conditions, one can deterministicly predict exact outcomes of any event ''before it happens''. QM clearly shows this to be not true; one can only predict the probability of any event happening; even perfect knowledge of initial conditions cannot, for example, predict the exact time when a single discreet particle will decay. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 16:48, 28 June 2011 (UTC)


Example: Deutsch' thought experiment involving superpositions of entire observers observing different outcomes. Here one considers observing the z-component of a spin that is polarized in the x-direction. If the whole system of observer plus spin is isolated from the environment, the entire system will be a superposition of the two outcomes. Then the observer in each branch forgets, in a reversible way, the outcome of the measurement, by dumping the information back on the spin. That then restores the spin to its initial state. The observer, however, does keep the information that a measurement of the z-component was carried out.

The observer can then verify that the spin is polarized in the x-direction after this procedure, even though he remembers measuring the z-component. This then proves that when the z-component was measured, both sectors in which different outcomes were obtained really exist (if only one sector really exists after measurement, the spin would not be restored to its original state). [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 18:00, 28 June 2011 (UTC)


Another example: Quantum mechanics in a timeless universe.
Many theoretical physicists believe that time doesn't exist (my opinion is that those that do think time exists mostly haven't thought this issue through to its logical conclusion). Then the world today can, in this interpretation, be said to exist in the early universe as a complicated non-local superposition. [[User:Count Iblis|Count Iblis]] ([[User talk:Count Iblis|talk]]) 18:28, 28 June 2011 (UTC)

::Jayron, you can interpret QM however you want. That will not change the fact that, as Count Iblis pointed out, |a'> = 1/sqrt(2) [|a> + |b>] is also a possible state so superposition of states is allowed. This has been confirmed by experiment [[ad nauseam]]. [[User:Dauto|Dauto]] ([[User talk:Dauto|talk]]) 01:00, 29 June 2011 (UTC)
:::Nothing I said has ever denied that. I, infact, fully endorse that, and I will again thank you for agreeing with me. The equation noted by Count Iblis is true, and doesn't need me to agree with it to be true. I don't see where I ever said it was wrong, however. The real existance of superposition of states is real and really exists. I don't know how many more ways I can say that to make you think that I agree with it, which I do. (and again, my agreement is not needed for its real truth to be really true). I should also note that I don't interpret quantum mechanics in any manner. I don't have any particular wants about how it is interpretted, and have nothing to add to existing scholarship on the issue. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 01:04, 29 June 2011 (UTC)

== MRI question ==

Would an MRI be better at finding bullet fragments then an xray? [[User:Googlemeister|Googlemeister]] ([[User talk:Googlemeister|talk]]) 15:45, 28 June 2011 (UTC)

:You probably need to define "better." MRIs are bulkier, more expensive, and harder to transport than a standard x-ray radiograph imager. [[User:Nimur|Nimur]] ([[User talk:Nimur|talk]]) 15:47, 28 June 2011 (UTC)

::There are risks with taking MRIs of bodies containing magnetic metals. Even though bullets are typically made of non-metallic lead, there may be fragments of magnetic metal from the shell casing, and steel ammunition is sometimes used (e.g. in shotgun pellets). Studies show that the metal fragments are unlikely to move much, but there is a risk of damage to internal organs.[http://www.mrisafety.com/safety_article.asp?subject=47][http://www.strokecenter.org/patients/diagnosis/mri.htm] --[[User:Colapeninsula|Colapeninsula]] ([[User talk:Colapeninsula|talk]]) 15:55, 28 June 2011 (UTC)

:::"Non-metallic lead" ? I assume you mean "non-magnetic". [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 16:10, 28 June 2011 (UTC)

:::Better as in more likely to find the bullet fragments, the bulkyness of an MRI vs an xray machine is probably not of paramount importance (unless you are talking about military field applications I suppose) since both are too large to fit into your standard ambulance and cost usually isn't the biggest concern of someone with a bullet in them. I did not consider that some ammunition was steel. I guess I need to read up on that. [[User:Googlemeister|Googlemeister]] ([[User talk:Googlemeister|talk]]) 16:07, 28 June 2011 (UTC)

:I would expect bullet fragments to show up quite nicely on an X-ray, so no need to resort to the more expensive MRI. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 16:11, 28 June 2011 (UTC)

::To expand on StuRat's statement, I would expect that (ignoring all other factors such as cost and complicatedness of use, complications due to magnets, and other issues) that an X-ray would be equally as good as an MRI in finding bullet fragments, that is once the image is obtained, a trained professional should have no more trouble finding a bullet in the image with an X-ray image than with an MRI image. If we include the other issues already noted above, the X-ray is probably better than an MRI for this application. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 16:14, 28 June 2011 (UTC)

::Here's a useful link: a research paper that performed comparative virtual autopsy using MRI and CT, and comparing them to the X-ray radiography: [http://www.fsijournal.org/article/S0379-0738%2803%2900225-1/abstract ''Image-guided virtual autopsy findings of gunshot victims performed with multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) and subsequent correlation between radiology and autopsy finding''] (2003). [[User:Nimur|Nimur]] ([[User talk:Nimur|talk]]) 16:17, 28 June 2011 (UTC)

:::I think there needs to be some clarification on your use of the term "x-ray" -- CT scan machines emit ionizing radiation, as do conventional x-ray machines, so what exactly would be your criteria for separating the two? Projectional x-ray images (such as a chest x-ray or a dental panoramic radiograph) would not locate the bullet fragments in 3 dimensions, making localization of the fragments for surgical removal difficult. A full body CT scan (or CT scan of that portion of the body known to possess the fragments would allow the practitioner to see the fragments in an axial slice. Whether or not MRI would be better or worse, though, I cannot say, because (as a dentist) I'm completely unfamiliar with MRIs. '''[[User:DRosenbach|<span style="color:#006400">DRosenbach</span>]]''' <sup>([[User_talk:DRosenbach|<span style="color:#006400">Talk</span>]] | [[Special:Contributions/DRosenbach|<span style="color:#006400">Contribs</span>]])</sup> 17:00, 28 June 2011 (UTC)

::::With traditional X-rays, they take two, at 90 degree angles, to locate objects in 3D. For example, one from the front and one from the side. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 17:43, 28 June 2011 (UTC)

:Actually MRIs are very bad for finding metal. Metal objects don't even show up on an MRI; they distort the image in the area around them, though, making it sometimes possible to deduce their presence. Also if the metal is magnetizable (lead is not), the magnetic fields in an MRI will exert a strong force on it, which is obviously not a very good thing for a bullet fragment. CTs are absolutely perfect for finding metal, even tiny pieces just leap out at you if you look at one. [[User:Looie496|Looie496]] ([[User talk:Looie496|talk]]) 02:10, 29 June 2011 (UTC)
::I was just about to say the same thing, but Looie beat me to it. [http://www.springerimages.com/Images/MedicineAndPublicHealth/1-10.1007_s00401-003-0683-4-3 Panel (b) of the figure on this page] shows an MR image of a brain with a bullet lodged inside. The bullet's distortion of the magnetic field causes the dark 'hole' and the adjacent bright 'flare'; you'd see something similar with any metallic object. Not only does it make it very difficult to precisely locate the bullet itself, but it also conceals and distorts the appearance of nearby anatomical structures. With steel (or other ferromagnetic) shrapnel, pellets, or bullet fragments, one also has the additional risk of local heating and migration of the metal item in the magnetic field, which [http://www.mrisafety.com/safety_article.asp?subject=47 may cause pain or injury]. [[User:TenOfAllTrades|TenOfAllTrades]]([[User_talk:TenOfAllTrades|talk]]) 02:39, 29 June 2011 (UTC)

== Multiple Alleles ==

Hello. If the dominance hierarchy of coat colour in [[Netherland Dwarf]]s is C (dark gray) > c<sup>ch</sup> (chinchilla) > c<sup>h</sup> (light gray) > c (albino), why do c<sup>ch</sup>c<sup>ch</sup> and c<sup>ch</sup>c code for light gray instead of chinchilla and why do c<sup>h</sup>c<sup>h</sup> and c<sup>h</sup>c code for point restricted instead of light gray? Thanks in advance. --[[User:Mayfare|Mayfare]] ([[User talk:Mayfare|talk]]) 17:36, 28 June 2011 (UTC)
:Because binary genetics (even multiple allele binary genetics) is rarely useful for anything more than pedagogical purposes; that is it is helpful in demonstrating the basic principle, but in actual practice, the physical traits expressed by genes are often the result of complex effects, sometimes in the second or third order (for example, the gene doesn't directly code for the structure of the pigment, it codes for the structure of a component of the pigment, or it codes for the structure of a substance that is involved in the manufacture of the pigment some several steps back from the pigment itself). In particular, broad traits such as pigmentation represent what are called [[polygenic trait]]s which are coded by multiple genes. For some analogs in humans, see [[Eye_color#Genetics]] and [[List_of_human_hair_color_genes]], which lists for humans some 12 genes responsible for hair color; you'll also note that many of these genes code for things OTHER than hair color as well, that is there are not only multiple genes which determine hair color, there are multiple traits coded for by each gene (of course, depending on how you define "trait"). I would expect the genetics of other mammals to be similarly complex. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 19:09, 28 June 2011 (UTC)
::I took the liberty of linking Netherland Dwarf above, as I didn't know it was a [[rabbit]]. ;) (''[[Oryctolagus cuniculus]]'' to be precise) Here's a public access paper about the ''E'' (extension) locus and a similar dominance sequence,<sup>[http://www.biomedcentral.com/1471-2156/11/59]</sup> but I'm still hunting... alright, finally got someone to say that the c (albino) locus is indeed [[tyrosinase]] in ''O. cuniculus''<sup>[http://www.springerlink.com/content/jnwdjfxga0bgwu0x/]</sup> (never take that sort of thing for granted...) ''chinchilla'' and ''albino'' alleles are indeed due to mutations in the CDS (compared to C (dark gray). Which leaves light gray... didn't find that; there's only one sequence coming up in NCBI, namely [http://www.ncbi.nlm.nih.gov/nuccore/NM_001082077.1]. I even ran a BLAST search and came up with no other nucleotide sequences. It looks like the relevant work may be so old it isn't indexed - indeed, perhaps the sequence was never determined. This is generally the point where you have to pick up a phone and call someone on the last paper to come out about it in the hope of getting some answers, which I'm not going to do now for this exercise; my guess is that we're looking at some very old data. So I can't say ''exactly'' why these alleles would have a more peculiar dominance pattern. Also, the data you describe sounds unlikely - I'd expect two recessive alleles of the same type to deliver the advertised phenotype! Hmmm... for further information see [http://www.nffgrb.com/Articles/Article-Genetics1.html] - it's apparent there is a lot more breeding of rabbits going on than I'd ever imagined! ;) And yes, two chinchilla alleles can lead to a light gray color, though there's some lingering confusion on the point. Hmmm, so much data and so few sequences in NCBI :( [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 23:19, 28 June 2011 (UTC)

== From the Caspian Sea to the Black Sea ==

I included two questions in a posting above, and one of them got no attention, so here it is alone.
:
Is there any truth in Leonardo da Vinci's statement that there are subterranean rivers flowing from the Caspian Sea to the Black Sea? [[User:Michael Hardy|Michael Hardy]] ([[User talk:Michael Hardy|talk]]) 20:49, 28 June 2011 (UTC)

::That seem highly unlikely as the Caspian Sea is actually 28 metres lower than the Black Sea and there is the [[Caucasus mountains]] in between. Any river flow would be from the mountains of the Greater or Lesser Caucasus ranges into one or the other seas. [[User:Mikenorton|Mikenorton]] ([[User talk:Mikenorton|talk]]) 21:17, 28 June 2011 (UTC)
:::As an aside, there has been means of getting between the seas for quite some time. The [[Volga–Don Canal]] goes back several hundred years; and since the Volga and Don are relatively close (100 km or so), that makes [[portage]] between the rivers (and thus between the Caspian and Black seas) reasonable even before the canal was built. However, this has nothing to do with natural river flows between the seas; as noted water generally doesn't flow uphill. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 23:24, 28 June 2011 (UTC)
::::The Volga–Don Canal seems to go back to 1952 except for a couple years in the early 1700s. [[User:Rmhermen|Rmhermen]] ([[User talk:Rmhermen|talk]]) 02:55, 29 June 2011 (UTC)

== Are we evolving? ==
[[File:Skeleton of a man of the future.svg|thumb|right|We are evolving. Into this.]]
Is the human species evolving? Indeed, since modern medicine is able to keep alive humans who would die under other circumstances, then, we are indeed getting weaker. [[User:Wikiweek|Wikiweek]] ([[User talk:Wikiweek|talk]]) 21:49, 28 June 2011 (UTC)

:As long as some people die earlier, and reproduce less, than others, evolution will continue. It might possibly slow down or evolve in a different direction (say favoring people genetically predisposed to use seat belts), but it won't stop. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 21:52, 28 June 2011 (UTC)

:Evolution is just gene flow over time. That happens just by living and reproducing and so forth. If you mean, "are less favorable traits being selected for over time?" (e.g. [[dysgenics]]), it really becomes a question of what one defines as "less favorable." It's a pretty subjective measurement and the level of subjectivity becomes clear when you consider some traits that are widely shared and found to not be such a big deal, but would have been a significant hindrance (or even fatal) a long time ago, such as poor eyesight or appendicitis. In the case of IQ, there is evidence that has only risen over time (see [[Flynn effect]]). If by "weaker" we mean only "that they would have not survived without modern medicine," we can only then ask why we should take that as a meaningful criteria. There are lots of people who wouldn't have survived without modern morality or social institutions, in general. What does that tell us except how lousy the past was?
:It's also a fallacy to consider modern medicine somehow "unnatural" to the species. It's as natural as anything else we've been up to. It's new (from a species-long perspective), but that hardly makes it any less "natural". --[[User:Mr.98|Mr.98]] ([[User talk:Mr.98|talk]]) 21:59, 28 June 2011 (UTC)

::Define "weaker". Without "modern medicine" [[Stephen Hawking]] would have undoubtedly died from his disease long before he made many contributions to our understanding of how the universe works. Insofar as an improvement and refinement to the canon of human knowledge is generally a Good Thing, modern medicine has made people stronger. Also, there is the problem with defining humans as somehow "extranatural", that somehow what happens to us or is done by us is somehow outside of "nature", whatever that means. We're particularly good at altering our environment and ourselves in ways that benefit us (at least in the short term), but we're not unique in that regard; every other living thing constantly does that. We alter the environment in ''human'' ways, but that's not necessarily a meaningful statement; rabbits alter the environment in lupine ways, and trees alter the environment in dendritic ways. We're active parts of the system, not passive managers or observers of it... --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 23:20, 28 June 2011 (UTC)

:::Yes, I like to refer to "artificial" as a subset of "natural", as anything man-made is indirectly made by nature. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 23:24, 28 June 2011 (UTC)

::::It's true that saving people who would have died frustrates one small step of natural selection - but natural selection, like death, is patient, and sooner or later - unless we fix such genes ourselves - it will drink its fill. Many of the genes we possess are optimized for conditions we don't expect to experience. Consider, to begin with, how remarkable it is that a species from Africa can survive exposure of any part of its skin to the bitter cold of the Arctic - because there have been some very cold years indeed, long ago. Mutations like the one in CCR5 were probably kept by our ancestors for thousands, maybe even millions of years, as a distant memory of other HIV-like outbreaks before this one - and, most likely, the same is even more true of the normal variant most people carry, against some other disease not yet identified.
::::In order to make good decisions about genetic therapy to compensate for the loss of natural selection, we should recognize that alleles arise at some point in history, and that while some are ancient and valuable, others are recent and have no special historical significance. Many of the cruelest genetic diseases are of the latter sort, arising in the person affected, or some recent ancestor. If we resolve to preserve the range of genetic diversity we inherited from people 1000 or 10000 years ago, while resolutely putting right any recent mutations that cause noticeable trouble, we can maintain our vital genetic diversity and human essence, permit the free flow of speculative evolution into the future, and yet counteract disease more effectively than if people died from it. [[User:Wnt|Wnt]] ([[User talk:Wnt|talk]]) 00:18, 29 June 2011 (UTC)
::::: Agreed, and even if we do "fix such genes ourselves", that will probably fall to a different kind of natural selection. People's preferences as to what genes are desirable, and which are not, will change over time to fit current conditions and cause evolution that way. [[User:APL|APL]] ([[User talk:APL|talk]]) 03:00, 29 June 2011 (UTC)

:How about a reference, here on the Reference Desk? Our article [[Human evolution]] includes the section [[Human evolution#Recent and current human evolution|Recent and current human evolution]]. Admittedly it is short, and I was surprised not to see a large article on this topic. PS: I have added an illustration of the creature into which we are evolving, according to [[Alexey Bystrow|a Russian scientist.]] [[User:Comet Tuttle|Comet Tuttle]] ([[User talk:Comet Tuttle|talk]]) 03:40, 29 June 2011 (UTC)

== Deep Tissue Massage ==

I was looking at the website of a day spa and one service they called "Deep Tissue Massage" which they described as "Is a type of massage therapy that focuses on realigning deeper layers of muscles and connective tissue." Realigning layers of muscle and connective tissue sounds like a bogus claim but if anyone has proof that it can really happen by one human's manual kneading I'd like to know.[[Special:Contributions/198.228.193.74|198.228.193.74]] ([[User talk:198.228.193.74|talk]]) 22:17, 28 June 2011 (UTC)

:Perhaps it helps just by stretching those muscles and connective tissue a bit. Even if those particular claims sound questionable, it still seems worthwhile, whether for psychological/stress-reduction/relaxation reasons or something else. [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 22:42, 28 June 2011 (UTC)

::At $85 for 50 minutes, I'm pretty sure it couldn't make me feel good enough not to experience [[Buyer's remorse]], but of course that's just me, and to each his own.[[Special:Contributions/198.228.193.74|198.228.193.74]] ([[User talk:198.228.193.74|talk]]) 22:49, 28 June 2011 (UTC)

:::<small>Oh, and I forgot to mention the primary benefit, working out all those farts inside you. Now you see why they charge so much. :-) [[User:StuRat|StuRat]] ([[User talk:StuRat|talk]]) 23:09, 28 June 2011 (UTC) </small>

:There's probably also a keen distinction between "I do XXX because of the way it makes me feel." vs. "I do XXX because it makes me healthier" here. As long as XXX doesn't otherwise harm you, there's probably nothing wrong with "doing it because it makes you feel better", which as far as I am concerned, is a positive enough outcome even if outlandish health claims aren't backed up by hard science. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 23:14, 28 June 2011 (UTC)
<small>
:: (But is it enough to trust the practitioner who makes the claims? I wonder this about chiropractics. Most of those chiropractic places have big banners advertising the health benefits of "laser massage" and other obvious flim-flam. Why would you let such a snake-oil salesman near your spine?) [[User:APL|APL]] ([[User talk:APL|talk]]) 02:04, 29 June 2011 (UTC)
::: The key phrase is "as long as XXX doesn't otherwise harm you". Its an important concept, and you should re-read my statement keeping that phrase in the forefront of your understanding of it. It is a conditional statement, and removing it from my writing above changes the meaning of it. It appears from your response that you inadvertantly removed that phrase when reading my writing, or ignored it, or otherwise didn't notice that I wrote it, so I thought it prudent to bring it to your attention again to assure that its full weight and meaning did not go unheeded. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 02:39, 29 June 2011 (UTC)
::::Oh yea, I noticed it. And I wasn't trying to refute you or argue with you. I agree completely. I was just thinking 'out loud'. I was thinking of a situation where procedure XXX is known safe or low risk, but the local practitioners appear to be flim-flam men making insane claims. Since you can't actually know for sure if something will "otherwise harm you" before you do it, and afterwards the question is kind of academic. [[User:APL|APL]] ([[User talk:APL|talk]]) 02:56, 29 June 2011 (UTC)
:::::Trudat. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 03:04, 29 June 2011 (UTC)
</small>

= June 29 =

== Isn't hair loss an evolutionary trait? ==

Is it really a health problem? I've no doubt that were it not for sexual selection, we could easily become hairless in the future. (And in case you're wondering, I've beautiful hair.) [[User:Imagine Reason|Imagine Reason]] ([[User talk:Imagine Reason|talk]]) 01:04, 29 June 2011 (UTC)
: I think you could say that for ''any'' trait that's genetic or otherwise hereditary.
: I imagine it's a very small comfort to the afflicted, though. [[User:APL|APL]] ([[User talk:APL|talk]]) 02:01, 29 June 2011 (UTC)

::Is there any decent study of the different rates of hair loss among different human populations. As a mature Australian of northern European ancestry, my shiny dome seems to be becoming larger by the day, but all my Australian Aboriginal friends of similar age still have masses of wavy locks. (It seems they use the same silver hair dye as me though ;-) ) My theory is that, in an evolutionary sense, keeping one's hair for longer mattered more in the Australian sun than in the Scottish mist. Anyone got any better information than my totally original research on this small sample? [[User:HiLo48|HiLo48]] ([[User talk:HiLo48|talk]]) 02:34, 29 June 2011 (UTC)

:::Our [[Baldness]] article does touch on a couple of studies that measured people's perception of the bald and balding, on the theory that this perception may serve a social purpose for the chrome-domed, and hence evolution and natural selection may have encouraged it. For you, that is. [[User:Comet Tuttle|Comet Tuttle]] ([[User talk:Comet Tuttle|talk]]) 03:36, 29 June 2011 (UTC)
::::<small>Somewhere there is a silverback gorilla who is just ''aching'' to have access to [[Just for Men]]. --[[User:Mr.98|Mr.98]] ([[User talk:Mr.98|talk]]) 03:42, 29 June 2011 (UTC)</small>

:''Unexpected'' hair loss can be a problem, i.e. a sign of illness of some kind. However, if some of your ancestors went bald, that would increase your odds of going bald due to genetics. ←[[User:Baseball Bugs|Baseball Bugs]] <sup>''[[User talk:Baseball Bugs|What's up, Doc?]]''</sup> [[Special:Contributions/Baseball_Bugs|carrots]]→ 04:42, 29 June 2011 (UTC)

== Antarctica without an ice sheet in the summertime? ==

I was watching a documentary about Antarctica a couple days ago and in it, it said that Antarctica is freezing, even in the summertime, because its ice sheet reflects the sunlight away from the land. But if Antarctica didn't have an ice sheet (and assuming the continent [http://www.globalwarmingart.com/wiki/File:Antarctica_Without_Ice_Sheet_png wouldn't be flooded from what I see from this image]), approximately how hot would it be in the summertime, when the sun shines on the continent for half of the year? [[Special:Contributions/64.229.6.52|64.229.6.52]] ([[User talk:64.229.6.52|talk]]) 02:02, 29 June 2011 (UTC)
:You can look to other locations on the antipodes from Antarctica which lack an ice sheet to get an idea. [[Barrow, Alaska]] has average daily temperatures about 10 degrees farenheit (5-6 degrees Celsius) over freezing. [[Tuktoyaktuk]] has similar temperatures. The closer you get to the poles, the colder it would get, even with several months of constant sun; the angle of [[insolation]] is so oblique that, though the sun is technically shining for months at a time, it provides very little heating. Imagine a ball thrown directly at a target, and then the same ball at the same velocity hitting the target with a very slight glancing blow. The amount of energy imparted to the target by the ball is very much tied to the angle it strikes the target at; its the same with the heating effect of the sun. BTW, you may also want to read [[albedo]] which is related to the initial presumptions about the effect of snow on the climate of Antarctica. --[[User:Jayron32|<font style="color:#000099">Jayron</font>]]'''''[[User talk:Jayron32|<font style="color:#009900">32</font>]]''''' 02:53, 29 June 2011 (UTC)
::<small>Should you really be using an analogy using momentum? [[User:Comet Tuttle|Comet Tuttle]] ([[User talk:Comet Tuttle|talk]]) 03:33, 29 June 2011 (UTC)</small>
::{{ec}}Note that those figures for Barrow are the average '''high''' temperatures in the '''summer'''; the average temperature year-round is well below freezing. I suspect that the reflection of ice has some effect on the near-surface temperature; but not much, especially near the ocean. A good deal of the low temperatures in the coldest areas of Antarctica are due to it being as high as some of the highest mountains in the United States; due to [[adiabatic cooling]], the higher you go above sea level, the colder it will be. [[Vostok Station]], which had the coldest temperature ever recorded on the Earth's surface, is almost {{convert|3500|m|ft}} above sea level, atop a giant ice sheet miles thick. Compare its mid-summer average temperature of ({{convert|-32.1|C|F}}) to that of [[Alert, Nunavut]], [[Canada]] ({{convert|3.3|C|F}}), which is further north, but is at sea level; this is almost the exact difference you would expect for an elevation change of 3.5 kilometers.-<b>[[User:Runningonbrains|<span style="color:#000">Running</span><font color="blue">On</font><font color="green">Brains</font>]]<sup>([[User talk:Runningonbrains|talk]])</sup></b> 03:37, 29 June 2011 (UTC)

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