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May 13

Superconductors

What is the application of the diamagnetic nature of a superconductor?117.204.4.192 (talk) 09:04, 13 May 2010 (UTC)

I don't know. What does your class textbook say that it is? --Jayron32 20:37, 13 May 2010 (UTC)

See the article Meissner effect. One application is making a video of a levitating magnet. Cuddlyable3 (talk) 22:28, 13 May 2010 (UTC)

Maglev trains, among other cool stuff. FWiW 67.170.215.166 (talk) 04:27, 14 May 2010 (UTC)

Genetic predisposition to food types

Could an individual have a tendency, from birth, to like or dislike certain types of common foods? I believe the answer is yes, but I'm not sure where to go to find the research, if it exists. Personally, I've found myself drawn to certain types of foods throughout my life for no rhyme or reason, even foods I've never tried before. And it's not just the smell or presentation of the food, but something else altogether. Viriditas (talk) 09:09, 13 May 2010 (UTC)

Appetite, Pica (disorder) talk on this topic somewhat. Graeme Bartlett (talk) 09:17, 13 May 2010 (UTC)

There is much research now on what shapes our food preferences. The dominant factors are feeding practices of mothers early in life. Genetic factors play a very small role. The rare but notable exceptions are the rare genetic diseases in which particular foods cause immediate adverse reactions, like fructose intolerance. alteripse (talk) 10:38, 13 May 2010 (UTC)

The article on taste mentions large genetic variability to detecting some types of bitterness. I've seen suggestions that preferences to some vegetables is affected by this. Try more on google (genetic bitter vegetable etc). 88.112.56.9 (talk) 10:59, 13 May 2010 (UTC)

If you look up your Western star sign you might find that some websites devote some coverage to food preferences. I myself am a Cancer-Leo cuspian and one website was quite correct in proclaiming that my life revolves around food -- as well as which particular foods. This isn't genetic per se, but you can't change your date of birth, so it almost is. Vranak (talk) 14:49, 14 May 2010 (UTC)

Sorry I thought this was the science desk not the pseudoscience desk. My mistake... Nil Einne (talk) 02:05, 17 May 2010 (UTC)

Using heat pumps instead of cooling towers

Would it be possible to use heat pumps to cool the water produced by power stations instead of having cooling towers and generate more electricity using the hot water produced, whilst also getting rid of an eyesore? If not why not? 131.111.30.21 (talk) 10:25, 13 May 2010 (UTC)

Heat pumps are working the wrong way round, using energy to move heat, whereas in a power station we want the transfer of heat to produce energy. Graeme Bartlett (talk) 11:30, 13 May 2010 (UTC)

What you can do is a combined heat/power process, where the "lost" heat is used for home heating and hot water. This is reasonably widespread in some European cities (it's extremely hassle-free, as you don't have to have your own burners and fuel supply), and has a number of other advantages. --Stephan Schulz (talk) 11:53, 13 May 2010 (UTC)

Also, a heat pump moves heat - so what are you going to do with the heat you just moved to cool the water? You'd need a cooling tower ..... Ariel. (talk) 12:04, 13 May 2010 (UTC)

Hmm, I thought there some way to concentrate the heat from the water in some way (a countercurrent exchange system of some form?) - isn't that the way that solar heating systems can make hot water even in the UK where the temperature is always lower than the temperature you'd want your hot water? 131.111.30.21 (talk) 14:49, 13 May 2010 (UTC)

The problem is entirely this matter of "concentrating the heat" - which is basically disallowed by the laws of thermodynamics. You can only take advantage of temperature differences and using that 'gradient' to take a more "concentrated" form of heat and make it less "concentrated". That said, you could use something like a sterling engine to extract more energy from the waste water - the problem being the relative capital and maintenance costs of such equipment compared to the dollar value of the energy they'd recover. All the while it's cheaper to build a second power station than it is to make the existing power station twice as efficient - nobody is going to do that. Hence the need for government regulation, taxes on carbon emissions, etc, etc. SteveBaker (talk) 15:57, 13 May 2010 (UTC)

Ah now I get you. I was thinking of a heat exchanger and not a heat pump, but now I see the problem. 86.7.19.159 (talk) 19:10, 13 May 2010 (UTC) (OP)

Cooling lakes are sometimes used at power plants rather than cooling towers. They offer recreation in the form of fishing. A particular fish species may find the temperature it likes in the thermal gradient of the lake and plant itself there. I suppose that for a small generator or on with lots of real estate, the heat could be dissipated via loops of plastic pipe buried in the ground, or by fins which transfer heat to the air, any of which could be assisted by heat pumps. Any of those are likely to be far more expensive than industry standard practice. A U.S. government pilot program of the 1960's - 1970's called the "Modular Integrated Utility System" (MIUS) would have provided trash incineration supplemented by fossil fuel to generate the heat needed to treat the waste water and sewage and to generate electricity for a neighborhood, and the waste heat would have been used to provide heat and water heat and air conditioning for the homes (yes, absorption cooling units can cool with heat). "Not in my backyard" views scuttled the program, but low grade heat from a power plant still contains useful energy which can be used in industries, businesses or even residences within a few blocks of the power plant, turning a liability into an asset. A factory is a better prospect for siting near a powerplant than a business complex or school or residential community. Edison (talk) 18:47, 13 May 2010 (UTC)

Speaking of fishing in a powerplant cooling lake, you could take the warm water from the powerplant's condensers and supply it to a shrimp farm (shrimp generally like warm water). However, the water would have to be artificially aerated (when cold water is heated, air comes out of it) and possibly disinfected (bacteria like warm water too) before being used in this way. FWiW 67.170.215.166 (talk) 04:34, 14 May 2010 (UTC)

See for example Calvert Cliffs Nuclear Power Plant. I had heard that the bay-perimeter fence half-depth (a solid curtain at the upper level, open below) to make the enclosed pool fill from the deeper water in the bay itself rather than being a normal vertical cross-section. So the cooling water is cooler. DMacks (talk) 06:47, 14 May 2010 (UTC)

Geographic center of USA

A quote from Geographic center of the contiguous United States.

In 1918, the Coast and Geodetic Survey found this "center" by balancing on a point a cardboard cutout shaped like the U.S.

Which map projection was used for the cardboard? Has anyone calculated the center taking into account the shape of the Earth? (Igny (talk) 10:33, 13 May 2010 (UTC))

Computer PSU

Hello people, I wanted to know if a computer PSU works like any other PSU? I know the AC current is put to a high frequency, and then transformed (thats why the transformers(there are more for the different voltages)can be that small), but my question is does all the power go thru these small trasnformers?So basically the Voltage is transformed by the transformers, am I right ? Or do newer models have a different technology?

Thank you and excuse my english

DST —Preceding unsigned comment added by DSTiamat (talk • contribs) 12:19, 13 May 2010 (UTC)

Does the article Switching power supply help? Ariel. (talk) 12:45, 13 May 2010 (UTC)

I have read the article, but I cannot find an answer to my question, does all the power go through these transformers? —Preceding unsigned comment added by DSTiamat (talk • contribs) 13:05, 13 May 2010 (UTC)

It seems that the power is made into a higher frequency, then transformed through those transformers, then rectified. So all of the current, except for maybe some safety devices, would go through the transformers. --Chemicalinterest (talk) 13:22, 13 May 2010 (UTC)

I don't understand your "made into a higher frequency". Is there something mysterious that I don't know about PSUs? I thought they were just transformers, rectifiers and smoothers. I'll have to take one apart to check! Dbfirs 17:52, 13 May 2010

Yes, made into a higher frequency because at higher frequencies the transformer can be a much smaller size, thats why Comp PSU's have so small transformers, I was , and still am curious if all the power goes through these small transformers ( can someone confirm this for sure?)

Do modern PSUs use some sort of inverter fed from the (rectified) input AC to generate the higher frequency then? The PSUs that I replaced (long ago) had none of this solid-state technology. I have some Switched-mode power supplys but they have only a very low current output. Dbfirs 18:56, 13 May 2010 (UTC)

Having read the article, the answer to both our questions seems to be "yes". I'm evidently very much out-of-date! Dbfirs 19:16, 13 May 2010 (UTC)

Switch-mode power supplies work by rapidly turning a semiconductor switch on and off; the switch connects a DC voltage level (which is higher than the desired desired voltage) to a rectifier and filter. The output voltage is sensed, and the duty cycle of the switch is adjusted to achieve the desired output voltage.

As stated, changing the 50 or 60 Hz input to some higher frequency with an inverter may allow any desired DC voltages to be generated with smaller transformers. Also, this simplified description treats inverters and switching power supplies as separate units; in actual practice, clever combination might be made, which would reduce the number of components. Jc3s5h (talk) 19:31, 13 May 2010 (UTC)

BUT.......... the basic principle is the same, AC current gets transformed through the trasnformer(which is small because its allowed by the high frequencies) to lower voltage, am I right? meaning all the power goes through the small transformer , then gets filtered etc? —Preceding unsigned comment added by 86.122.172.224 (talk) 19:50, 13 May 2010 (UTC)

That's right. Using the higher frequency allows the same amount of power to be handled by a smaller transformer. The capacitor(s) for smoothing the rectified output can also be smaller. Cuddlyable3 (talk) 22:06, 13 May 2010 (UTC)

... and instead of the heavy iron core needed for 50 or 60 Hz, a much lighter ferrite core with just a small number of windings is adequate. Clever! Our article on Power supply unit (computer) does say "Most computer power supplies are a type of switched-mode power supply (SMPS)". When did this type of PSU start being used? It's a long time since I took one apart. Dbfirs 06:27, 14 May 2010 (UTC)

... ... There seem to be two different designs: 1) rectify mains voltage, switch it to create a high frequency AC, transform it down to the required voltage, smooth & rectify and add a control circuit to achieve good load regulation ... and 2) rectify mains voltage and just switch it to give the appropriate fraction, then smooth & control switching. The second design doesn't need a transformer, but it is not used in computer PSUs because isolation from household mains voltages is required and also because the transformer design is more efficient for large voltage stepdowns. It's all there in the article - it just needs careful reading! Dbfirs 06:50, 14 May 2010 (UTC)

dandelions

Have dandelions evolved over the many years of humans picking them and blowing the seeds for fun, so have easy to break steams that allow humans to pick them easily and thus spread their seeds? —Preceding unsigned comment added by Javonicia (talk • contribs) 13:31, 13 May 2010 (UTC)

Unlikely. Humans picking dandelions to blow the seeds off is an extremely small % of the dandelion population, and from what I can tell, those seeds would have been windblown in any case. Googlemeister (talk) 14:25, 13 May 2010 (UTC)

(ec). It's possible, but it would be hard to tell since the seeds are windblown anyway. The stalks are actually not all that easy to break off anyway - they don't snap without some effort. Matt Deres (talk) 14:29, 13 May 2010 (UTC)

Do you only pick the ones that are easy to snap off, or do you pick any of the ones you see? Because if you pick them and blow the seeds without discrimination, there really is no genetic difference other than "easily visible." In order for evolution to occur, I believe that you would have to pick only the ones with certain traits. Even then, as Googlemeister said, it really probably would only be an incrdibly minimal factor in the success of the dandelion species. Falconus^{p t c} 23:10, 13 May 2010 (UTC)

AGE

I just found out parrots live for 100 years WTF??? How come parrots who are smallish live so long when other small animals only life a few years?? —Preceding unsigned comment added by Veltarka (talk • contribs) 15:37, 13 May 2010 (UTC)

Read Senescence#Theories of aging. Mathew5000 (talk) 15:56, 13 May 2010 (UTC)

Size and longevity don't always correlate. Dauto (talk) 16:23, 13 May 2010 (UTC)

True, the orange roughy has been show to live to 149 years old but is at maximum 75cm long. 86.7.19.159 (talk) 19:15, 13 May 2010 (UTC)

I'm curious, what enables some animals to live so long, while others only life a few years? Is longevity genetic, and could the longevity gene be introduced to any animal? 82.44.55.254 (talk) 20:36, 13 May 2010 (UTC)

As linked above, see the Senescence article and the articles linked from there. Comet Tuttle (talk) 20:45, 13 May 2010 (UTC)

Advanced Human

I know this is not known or maybe possible, but in this novel, shouldn't an "advanced" human have fewer chromosomes than the present day human? Reticuli88 (talk) 15:39, 13 May 2010 (UTC)

There is no relationship between chromosome number and any criterion for "advanced-ness". Chromosome numbers can change in both directions with speciation but do not change during the lifetime of a species. There is also no evidence that the number of human chromosomes is lower than it used to be. The only remotely tangential speculation that might support that direction is that the Y chromosome has shrunk to carrying very few functional genes and there has been some speculation about its eventual disappearance. alteripse (talk) 16:19, 13 May 2010 (UTC)

(Edit Conflict) Chromosomes are just a way of packaging genes into managably-sized bundles, but their absolute number doesn't mean a lot, except that successful reproduction producing fertile progeny usually prefers a match. For example, the Chimpanzee-human last common ancestor had its genes bundled into 24 pairs of chromosomes. Some time after the two lines diverged, the human line joined up two of them (to create Chromosome 2 (human) - and we can still see the join, though most of the same genes are still present), so we now have only 23 pairs while chimps still have 24 - do you consider chimps "more advanced" than humans? Many other organisms also have more chromosomes than humans - see List of organisms by chromosome count.

In one way it could be argued that having more genes is advantageous, and actually enables "advancement". If a complement of genes all have existing functions, there aren't any "spares" that can mutate to give additional new advantageous ones without losing the existing functions (probably fatally). If however an organism doubles its complement of chromosomes and hence genes by polyploidy (as mentioned in the Lasher article), it has a complete set of spares, any one of which can mutate while still leaving the "original" to continue the existing function. This has happened often (and usefully) in many plants, including the grasses that comprise most of our cereal crops (it makes hybridisation (biology) much easier for them), and has demonstrably happened more than once far back in our (that is to say vertebrate animals') genetic ancestry. 87.81.230.195 (talk) 16:28, 13 May 2010 (UTC)

Ok, thank you all for your answers. I have a better understanding now. Reticuli88 (talk) 18:47, 13 May 2010 (UTC)

decision and truth tables

Decision and truth tables seem to be the same in that actions or items are distinct and separate by having unique conditions or characteristics. Because both animals and plants contain minerals and some animals contain cells which photosynthesize shouldn't the current system of classification into kingdoms be called a fuzzy system of classification? 71.100.0.29 (talk) 16:01, 13 May 2010 (UTC)

Almost all biologists nowadays favor a system of classification based on ancestry, which is not fuzzy except in the rare cases of hybrids. Properties such as photosynthesis are helpful in determining common ancestry, but they are only aids, not the defining features. Looie496 (talk) 20:42, 13 May 2010 (UTC)

Well Horizontal gene transfer arguably also complicates things somewhat (well you can still go by ancestry but you're only getting part of the picture). Of course as explained at Kingdom (biology), the kingdom classification system, while widely used isn't considered adequete by some biologists anyway and even if it is used precisely what to have as the kingdoms. And as noted there and in eukaryotes the division of eukaryotes is also in major flux (although no one is suggesting plants and animals shouldn't be in different groups). Nil Einne (talk) 16:52, 14 May 2010 (UTC)

Electromagnentic Flow Meter

Why is the performance of a eletromagnetic flow meter not affected by the conductivity of the fluid? —Preceding unsigned comment added by 98.172.86.215 (talk) 20:04, 13 May 2010 (UTC)

See the Wikipedia article Magnetic flow meter and also this video. The meter requires a conducting fluid whose positive and negative ions will move in opposite directions at right angles to the flow and magnetic field directions. The conductivity of the fluid is hardly significant because there is neither an external voltage nor an external load to cause a current to flow. Cuddlyable3 (talk) 22:50, 13 May 2010 (UTC)

Ok so why doesn’t the concentration of free ions in the fluid impact the measurement? I would have thought (obviously incorrectly) that at a given flow rate a low concentration would yield a small potential and a higher concentration would yield a higher potential, and this would look like an error in flow rate due to a change in concentration.

I fixed your indentation. Please sign your posts. Cuddlyable3 (talk) 22:50, 13 May 2010 (UTC)

I think the electrolyte has to be uncontaminated so that all that flows is free ions. Cuddlyable3 (talk) 22:50, 13 May 2010 (UTC)

Don't understand. If a mag meter is calibrated on water and then used on a product with a different concentration of free ions; why is there not a calibration shift? —Preceding unsigned comment added by 98.172.86.215 (talk) 23:28, 13 May 2010 (UTC)

medical marijuana

Isn't medical marijuana provided by prescription to cancer patients throughout the United States for drops of THC they can smoke in their electronic cigarettes? 71.100.0.29 (talk) 21:55, 13 May 2010 (UTC)

We have an article about this very topic, Medical marijuana and Medical cannabis in the United States. Vespine (talk) 22:16, 13 May 2010 (UTC)

Specifically, 4th paragraph in Medical cannabis which states the route of administration is varied; the cannabis can be taken in a vapourised form, or it can be ingested. Regards, --—Cyclonenim | Chat  22:20, 13 May 2010 (UTC)

These articles provide a lot of information but do not state what the issue is with use of medical or recreational marijuana. What exactly is the issue? I've heard it keeps people from remembering but does that mean it keeps them from reasoning as well? Why are so many people against the use of cannabis? The articles fail to say. 71.100.0.29 (talk) 23:50, 13 May 2010 (UTC)

I didn't read that into your initial question, to answer that the relevant article would be Marijuana. Vespine (talk) 00:09, 14 May 2010 (UTC)

Cannabis might increase the risk of certain psychological disorders, does increase your risk of cancer, and can increase your heart rate significantly compared to its usual rate increasing the stress placed upon your heart. There are other risks which have not been firmly established in scientific literature, such as it's role in strokes. Cannabis is also often mixed with other ingredients, which can present their own hazards. No one denies that cannabis can have very (sometimes enjoyable!) effects, but there are also problems associated with smoking it, the most widely proven one being cancer. Regards, --—Cyclonenim | Chat  00:33, 14 May 2010 (UTC)

That is not correct. "No strong epidemiologic or research evidence indicates that cannabis smoking causes lung cancer."[1] The study you are most likely referring to in support of your claim was a study of tobacco users who also smoked cannabis. Viriditas (talk) 03:42, 14 May 2010 (UTC)

In all fairness I think there is pretty good evidence that it does cause cancer, and this is based upon a simple assumption and various sources. Yes, when smoked with tobacco, it's a clear relationship, but burning any organic material is going to present at least a slight carcinogen risk. There are various sources on PubMed, for example, and whilst some suggest cannabis smoke is more harmful than tobacco smoke and the others vice versa, none deny that smoking cannabis produces carcinogenic compounds. I don't know about other routes of administration, but it seems to me fairly clear cut that smoking it will increase your risk of cancer. Regards, --—Cyclonenim | Chat  10:25, 14 May 2010 (UTC)

Please provide good evidence for your claim that cannabis causes cancer. I've looked at the literature, and such claims are either false or misleading. In fact, there is evidence showing that cannabis slows the growth of tumors. More recent evidence shows that it slows the growth of cervical and lung cancers. (Journal of the National Cancer Institute, 2008-01-02).[2] In any case, anyone familiar with the cannabis literature knows for a fact that there is no conclusive evidence that cannabis causes lung cancer and that if the drug is going to be used for therapeutic purposes, most physicians would therefore recommend that the patient ingest the drug orally or by spray to avoid the risk of inhaling carcinogenic material, therefore lessening the cancer risk, if any.[3] Scientific studies of cannabis vaporizer usage have shown that a "safe and effective cannabinoid delivery system seems to be available to patients." I therefore seriously question whether legal prescription drugs could be said to be as safe and effective as cannabis, and I question the safety of legal alcohol and tobacco in comparison. It can even be seriously argued that legal fast food restaurants pose more of a threat to human health than cannabis. Let's be perfectly honest and clear: Cannabis prohibition has nothing to do with protecting public safety or human health, and it never has. Viriditas (talk) 11:45, 14 May 2010 (UTC)

I sincerely disagree that cannabis prohibition has nothing to do with public safety or human health. Do you accept that inhaling any form of burnt organic material is likely to expose your body to carcinogens? This applies to cigarettes, to joints, and to incense and to fuels. I agree that a vapourised form of the drug is unlikely to cause cancer given our current evidence, but smoking a joint will expose your body to carcinogens. I was a little quick on the gun to say it causes cancer; what I should have said is smoking a joint will increase your chances of getting cancer--since you're smoking benzene and goodness knows what else!

Furthermore, there are new, slight links in cannabis smoking to chronic liver disease [4] and there is clear evidence that cannabis inhibits your senses sufficiently to impair your driving ability. These properties alone make cannabis very similar to alcohol in that regard, and as such there is an aspect of public safety and human health involved in this discussion.

Whether, as you mention, cannabis has a role to play in initiating mental health disorders or exacerbating them, surely it is a void argument? Not everyone will know they have a predisposition to mental health disorders, so not everyone who took cannabis, were it legalised, would be safe in taking it. As such. a minimisation of cannabis availability can only be a good thing in protecting the collective health of everyone.

I'll say again, I don't doubt that cannabis is beneficial in the right, pure form given medicinally under strict supervision. I do have issues with it being suggested as a safe drug on the street--especially as it's usually mixed with tobacco. Regards, --—Cyclonenim | Chat  15:33, 14 May 2010 (UTC)

The legal history of cannabis in the United States shows that cannabis prohibition is rooted in immigration issues related to its use by Mexican immigrants, African Americans, and other minorities. Technological competition may have also played a significant role, since hemp production threatened to replace the use of other industrial products. Cannabis was once prescribed by physicians as medicine, and the AMA opposed prohibition; At the time, the drug was widely available in tinctures and did not require combustion. Your concerns about cannabis and liver disease appear to be out of proportion to its risk. In the U.S., the legal, over-the-counter analgesic drug paracetamol (acetaminophen) causes three times as many cases of liver failure as all other drugs combined and is the most common cause of acute liver failure in the U.S., accounting for 39% of cases...In the U.S. and the United Kingdom [paracetamol toxicity] is the most common cause of acute liver failure." Cannabis is safe in comparison. For the record, cannabis is not "usually mixed with tobacco" in North America. Mixing tobacco and cannabis is common in the UK and Europe, however, for reasons that elude me. Mental health issues (and human health issues in general) are greatly aggravated by poverty, unemployment, social and political unrest, lack of access to education and health care services, and many other factors; Cannabis is not the fundamental cause of any of this, but an excuse, a political distraction to avoid having to take responsibility for the real issues facing society. Viriditas (talk) 19:38, 14 May 2010 (UTC)

Whilst immigration as a reason may have been used in the United States, the worldwide view by governments and usually their official medical bodies have roughly agreed that cannabis is an illegal drug. Presumably, this is not without good reasoning. I don't doubt it had a role in the US in the way you mentioned, but these issues don't apply everywhere: particularly islands. I doubt that industrial production would be significantly affected by people smoking a bit more cannabis.

As I have said many times, I have no quarrels with cannabis being used in a liquid or clean vapour form. I can see the benefits of the drug in those cases, so your comment regarding the usage by historical physicians doesn't concern me. It does have it's uses! The problem comes with combustion of cannabis, whereupon carcinogens are released. This presents a risk to the active smoker and the passive smokers, whether established in epidemiological studies or not.

You cannot compare the use of paracetamol to cannabis with respect to liver failure. I'll explain why. Paracetamol is the leading cause of acute liver failure, as you rightly suggested. This is mainly due to people in quite a bit of pain taking above the daily recommended allowances, or due to suicide attempts gone wrong (where the person is admitted to hospital well before the particularly fatal symptoms take hold). Cannabis, according to studies, is a potential cause of chronic liver failure, not acute, and produces a risk of liver failure over several years of consistent smoking of cannabis. Chronic and acute liver failure have different aetiologies. I'd like to see sources for your statements regarding its comparative safety compared to paracetamol.

With respect to mental health issues, it's naive to believe that cannabis smokers who get mental health issues only do so because of other factors; this is not clearly established in literature. So far it seems that some cases are greatly aggrevated by the factors you mentioned, but you fail to notice that most of those factors can come about from a drug addiction! People who get addicted to cannabis are likely to be less wealthy (since they're spending money on their habit), more likely to be unemployed and are likely to have disrupted social habits. I don't see how political unrest can directly play an effect on someone's immediate mental health, this seems very unlikely, but I'll accept your point regarding inadequete access to health services. Regards, --—Cyclonenim | Chat  20:57, 14 May 2010 (UTC)

No, I'm sorry, there is no good evidence that cannabis use contributes to chronic liver disease, and you have yet to provide any. And cannabis is clearly safer than commonly prescribed, OTC medicine, let alone prescription drugs that have known side effects. I've asked User:Alfie66 to comment as a professional drug researcher who has worked with cannabis in the lab. Viriditas (talk) 01:58, 15 May 2010 (UTC)

I'm sorry, how are you allowed to question my sourced claims, yet you provide no evidence for yours that OTC drugs are significantly safer than cannabis? Just in case you have a problem with that one source, how about this one [5]? There IS evidence that cannabis is harmful, you're just choosing to ignore it. I welcome comments from Alfie66 on this matter. Regards, --—Cyclonenim | Chat  16:22, 15 May 2010 (UTC)

Hi folks. I'm not sure whether you are montoring my talk page. I'll be back from the conference by next Thursday. In the meantime, does anybody know how to move this discussion to Talk:Medical_cannabis? I would recon that would be a better harbour. →Alfie^±Talk 20:04, 15 May 2010 (UTC)

In that line after fast reading the article I am still not sure what the cause for rejection is. The only thing in the article that comes close to describing the only personal experience I have ever had with a person who was smoking marijuana is mood change. They seemed to go from being neighborly and friendly to threatening within almost the same sentence. Not the kind of relationship I want to have. Is this the general negative, turn off experience or is there something else? 71.100.0.29 (talk) 00:58, 14 May 2010 (UTC)

Changes in behavior are typical of any psychoactive drug use, including periods of euphoria and depression. This is more pronounced with heavy users who are at risk for cannabis dependence. Of course, the person you are talking about might have been suffering from a mood disorder to begin with. Some studies have shown that these users may self medicate, as the cannabis might help them regulate their mood or possibly make it worse. I suspect it depends on the individual. In other words, it might help or hurt. Viriditas (talk) 04:01, 14 May 2010 (UTC)

Ok, hang on, back the truck up. what exactly are you asking? What do you mean "rejection"? Do you specifically mean "Why is it illegal in a lot of countries?" There are a few countries and states where it is not illegal, there are places where it is decriminalized. As with pretty much all drugs, the debate is about benefit vs. risk. Both sides of the debate have valid arguments, it's not a cut and dry issue. The people who argue for the drug to be illegal use the arguments that it is a dangerous drug, has been linked to various adverse health effects, such as psychosis and depression. There's a reason why it's called "dope" it can lead to apathy, can be a gateway drug to other more "hardcore" drugs.. Where it is illegal, these factors and probably others I fail to mention are argued to outweigh any "benefits". We also have an article specifically about Effects of cannabis which might be useful. Vespine (talk) 01:33, 14 May 2010 (UTC)

Certainly you would consider damage to a legally binding relationship such as abridgment of the obligation to comply with marriage vows due to smoking marijuana to outweigh any benefit such as relaxing at a weekend party? Does marijuana represent a risk to marriage if the wife or husband smoke marijuana at a party and loose all comprehension of their responsibility? While the initial effect may be physiological the end effect is sociological. What I am asking is if this is the reason or one of the reasons why some states still object, reject and outlaw marijuana? 71.100.0.29 (talk) 02:26, 14 May 2010 (UTC)

There is no "scientific" or "medical" reason for cannabis prohibition. It is primarily a social, political, and religious issue. Viriditas (talk) 04:16, 14 May 2010 (UTC)

Well believe it or not social science and political science are sciences which rely upon empirical data and statistical analysis no different than physical science relies on similar empirical measurements to approximate the weight of an electron. 71.100.0.29 (talk) 04:53, 14 May 2010 (UTC).

Issues, not science. Read the below. There's a lack of good data. Viriditas (talk) 05:23, 14 May 2010 (UTC)

There may be a lack of physical effect data but not a lack of social effect data recorded over the past 3,000 years. 71.100.0.29 (talk) 05:38, 14 May 2010 (UTC)

Hopefully, you're kidding. Viriditas (talk) 05:46, 14 May 2010 (UTC)

As most anyone who has been near a university campus in their growing years I had to make a decision as to whether to be a pot head or not. Since I was aware that effect data was the key I decided that was the place to start. I do not need physical effect data to tell me that pot is not good for society and not good for me. However, it would be a waste of time to try and persuade anyone who has not looked at the social effect data not to use pot themselves. Each of us has to make our own decision and live in a cloud of smoke or carry a bit of responsibility. I chose the latter. I hope that you did too. 71.100.0.29 (talk) 05:58, 14 May 2010 (UTC)

Responsibility requires making informed choices based on facts. Booth's Cannabis: A History, Pollan's Botany of Desire, and the culural history related to cannabis are at odds with your assessment. Willful ignorance is irresponsible and unethical. Viriditas (talk) 07:45, 14 May 2010 (UTC)

Facts are important but the hallmark of informed choice does not exclude the other side of the argument and/or metaphor. 71.100.0.29 (talk) 11:11, 14 May 2010 (UTC)

Please stop. Appealing to "social effect data recorded over the past 3,000 years" is one of the most ridiculous things I've ever read. Viriditas (talk) 11:21, 14 May 2010 (UTC)

How about the serious risk of injury to the public from devices with safety flaws that have found their way to market through companies who hired the engineers that designed the devices who are on crack and pot? 71.100.0.29 (talk) 11:54, 14 May 2010 (UTC)

How about the serious risk of injury to the public from rampant greed and political corruption? Surely, you must remember the Chinese protein adulteration scandal, the 2007 pet food recalls, the 2007 Chinese export recalls, the 2008 Chinese milk scandal, the 2008 Chinese export recalls, and the 2008 Chinese heparin adulteration? It might be time to reevaluate your priorities. Need I say that cannabis was not involved in any of the above? Viriditas (talk) 20:06, 14 May 2010 (UTC)

←

How about the serious risk of injury to the public from crazy lunatics who get high on pot and start shooting cops while in a state of reefer madness? 67.170.215.166 (talk) 07:21, 15 May 2010 (UTC)

Should be ban hydroxyethane? Many innocent bystanders are killed every year because some people attempt to operate heavy machinery when their reactions are dulled under its influence. 62.56.65.189 (talk) 11:35, 15 May 2010 (UTC)

Greed and ambition are natural and healthy phenomenon which can not be adequately regulated by legislators or politicians or bureaucrats or protesters or law enforcement who are on opium, alcohol, crack or pot. 71.100.0.29 (talk) 12:27, 14 May 2010 (UTC)

You've changed the parameters of your query three times now. This is an anonymous forum and no one is going to judge you based on the question you ask. Well they might but you can safely ignore them if you want. I suggest you think about specifically what you are trying to ask and just ask it, you are much more likely to get a straight answer then if you try to circle around the issue. Vespine (talk) 04:22, 14 May 2010 (UTC)

Bottom line is that if THC, cannabis and marijuana are already legal for medical use then what is the problem [ for drug dealers ] unless now the dealers and recreational users want to use it [ legally ] too because they consider the need to relax or to make money just as legitimate a reason as medical. 71.100.0.29 (talk) 05:08, 14 May 2010 (UTC)

Please do some research on the topic before making comments like this. The so-called "dealers" are vocally against legalization and are one of the strongest opponents. California newspapers have covered this in detail. When you legalize something, you eliminate the black market, and prices go down. Follow the money. Who benefits? Viriditas (talk) 08:21, 14 May 2010 (UTC)

I said unless. Legalization for medical use presents a whole new opportunity for abuse of the legal system by giving non-medical users and drug dealers an excuse that will assure even greater black market sales and profit from non-medical use on the grounds that their needs are just as deserving but not recognized although profit from drug tourists has proven that legalization might increase profit by increasing the volume of users. 71.100.0.29 (talk) 16:19, 14 May 2010 (UTC)

The opposite is true. This is not a criminal justice issue but one of public health. Throwing drug addicts in prison only makes them more addicted to drugs and burdens the prison system. Your ideas have been tried, and for forty years they failed miserably in the U.S., only increasing the profits of the black market and ruining countless lives. Your ideas don't work and society as a whole has decided it's time for a new approach. Experts acknowledge that the act of altering ones consciousness is not only a fundamental human right (cognitive liberty), but a basic human need. Viriditas (talk) 19:59, 14 May 2010 (UTC)

My ideas? I think not. What's more I said nothing about prison. Were it up to me I would simply fine them to help fund enforcement, revoke their citizenship and then deport them. Altering your consciousness is no problem until or unless it interferes with your legal obligations, which to the contrary requires your consciousness not be altered. 71.100.0.29 (talk) 00:29, 15 May 2010 (UTC)

So, you would have tried to remove Ronald Reagan from public office during his presidency, and deported Rush Limbaugh to Costa Rica? Viriditas (talk) 01:58, 15 May 2010 (UTC)

You have no right to project or to speculate what I would or would not do in support of your argument and in any case it is irrelevant and not the topic of this discussion. 71.100.0.29 (talk) 02:15, 16 May 2010 (UTC)

(edit conflict) As a schedule I drug, the US FDA sees no medical benefit to marijuana and doesn't allow any scientific study of its medical efficacy. The lack of scientific studies demonstrating medical efficacy is then used to argue that marijuana should remain a schedule I drug.

To answer the OP's question: no, THC and cannabis are not one and the same. Cannabis has THC, as well as dozens o other compounds that provide synergystic effects that haven't been thoroughly studied. On top of that, I was under the impression that the synthetic THC prescribed by doctors was in pill form. Either way, electronic cigarettes may not offer sufficient temperature control for vaporizing THC. — Ƶ§œš¹ _{[aɪm ˈfɹ̠ˤʷɛ̃ɾ̃ˡi]} 04:29, 14 May 2010 (UTC)

Cannabis oil is about 80% THC. Anyone cam make an electronic cigarette with a battery and a piece of nichrome wire of the right length and resistance to vaporize most any liquid but that was not the purpose of the question. The purpose was to confirm if the sale of THC for medical use was already legal. 71.100.0.29 (talk) 05:14, 14 May 2010 (UTC)

Many pills are 90% inert filler. Percentages of ingredients are not a good indicator of their effect in a medication. --Stephan Schulz (talk) 09:22, 14 May 2010 (UTC)

The first result of my search of WebMD is Marijuana - Marijuana Use and Effects of Marijuana, which mentions physiological effects, psychological effects, and risks. -- Wavelength (talk) 17:20, 14 May 2010 (UTC)

Just a couple things about that link.

1. "the rates of addiction to pot have risen significantly over that same period" The rates of people being admitted into drug rehabilitation for marijuana has risen. However, because drug court referrals make up the majority (56%) of people in rehab for pot and because drug courts themselves came about in the early 90s, it's easy to see how non-addicts caught with marijuana would prefer treatment over prison time.
2. "marijuana is addictive, at least psychologically" Part of the measurement of addiction (per the image in our article on substance use disorder) is "social effects" but marijuana's illegality is part of that social effect. Does this mean that legalized cannabis would be less addictive because there would be fewer social repercussions for using it? Also, many things can be psychologically addicting (work, chocolate, Wikipedia).
3. "The jury is still out on [the gateway theory]" Actually, the gateway hypothesis was refuted over 11 years ago in "Marijuana and Medicine: Assessing the Science Base," (specifically page 99).

WebMD is probably reliable on other things, but it seems to have a few facts wrong about cannabis. — Ƶ§œš¹ _{[aɪm ˈfɹ̠ˤʷɛ̃ɾ̃ˡi]} 18:12, 15 May 2010 (UTC)

Actually, Mr./Ms. Greek, there's been an article in the New Times (a publication by Voices United) that corroborates the increase in the addiction rate to marijuana, as well as the fact that today's marijuana is much more addictive than it used to be because of its much higher THC concentration (over 10% currently vs. 3% when pot smoking first became popular). The WebMD website is not wrong on these points, your evaluation is. 67.170.215.166 (talk) 23:53, 15 May 2010 (UTC)

Although strictly we're on the same side of this discussion, I'd prefer to see these statistics in a peer-reviewed journal than in a small-press newspaper. Newspapers aren't renounced for scientific accuracy. Regards, --—Cyclonenim | Chat  01:36, 16 May 2010 (UTC)

Another falsehood about marijuana. The potency of THC in marijuana varies considerably from what season it is cultivated, the climate it grows in, and how it's prepared when it's harvested. Even if Drug War reports about Marijuana's increased potency were true (which I doubt) I don't see how this makes marijuana more addictive or dangerous. Does that mean that pure THC pills are even more addictive? — Ƶ§œš¹ _{[aɪm ˈfɹ̠ˤʷɛ̃ɾ̃ˡi]} 03:15, 16 May 2010 (UTC)

I really wanted to stay away from this discussion as it is already way too long but I read something very interesting recently. Apparently what's happening is the total drug yield of the plant is not increasing, however the proportion of the THC component is what gets you high so people are breeding plants to have a higher proportion of THC. What is concerning is that this is at the expense of the other components, most importantly Cannabidiol (CBD) which is an atypical antipsychotic, but doesn't get you high. You can guess where this is leading. It is suggested that the CBD counteracts the psychotic effect of THC, by decreasing CBD and increasing the THC you increase the potential psychotic effects of THC. And before anyone accuses me of anything, I actually SUPPORT the legalization of marijuana, I don't think this would be happening to the extent it is if it was bought and sold in a legal and controlled way. Vespine (talk) 06:33, 17 May 2010 (UTC)

Interesting, do you remember where you read it? I'd like to have a look. How do you initiate legalisation, and how does that decrease it's usage? For the brief time following usage there will be both authorised pharmacists and illegal dealers giving out roughly the same thing, perhaps cleaner by the pharmacists. Whilst it'd be illegal for dealers to continue dealing, it already is! So you're going to have double the access to cannabis, and without more substantial research into it's harmfulness and/or benefits, I think that's a foolish move. Regards, --—Cyclonenim | Chat  08:26, 17 May 2010 (UTC)

I don't remember where I read it specifically, but looks like there's quite a bit online about it. This article maybe looks like a good start.. I have no idea how you initiate legislation, it's been done, there are 2 states in Australia where I live where pot is decriminalized, and i've been to Amsterdam where it is legal. Alcohol was illegal in the states for a while, so it might seem difficult but it's definitely not impossible. I don't expect usage will "go down" specifically, I also don't believe getting stoned is as harmful as getting blind drunk, or as smoking a packet of cigarettes a day, both which are perfectly legal. If it was legal, you wouldn't have "illegal dealers".. As for the harm minimization, medicinal marijuana is cloned, so the thc / cbd concentration is kept constant. Sure it wouldn't stop the back yard growers trying to breed their skunk as potent as possible, but that would no longer be the primary source, maybe especially for casual or first time users. Vespine (talk) 22:53, 17 May 2010 (UTC)

Nobel prize

Who is the youngest person ever got Nobel prize?75.168.114.180 (talk) 22:03, 13 May 2010 (UTC)

William Lawrence Bragg, aged 25, who shared the award with his father for their work using X-rays as a means of studying crystalline structures. Regards, --—Cyclonenim | Chat 

(After EC)I was going to say GIYF Vespine (talk) 22:24, 13 May 2010 (UTC)

Nice! That's what i want to know. Thank You!75.168.114.180 (talk) 01:01, 14 May 2010 (UTC)

May 14

Graupel... but not?

From what I've read here and on other sites, graupel is falling snow that has a nucleus of a snowflake but is otherwise an agglomerate of water condensation in the shape of a tiny ball. However, a lot of the examples seem to make graupel out to be heavy and pellet-like. What I'm wondering is if there is a word or descriptor for graupel-like snow that is as light as a feather... it simply won't land if there's enough of a breeze. I've been describing this snow as "styrofoam"-like to people I know, but no one has seemed to have seen it (rather, they just weren't paying attention). The coolest time I saw it was during a thunderstorm, there was thunder and the sky was full of floating super-light balls of rime (?) (near Denver, Colorado). They're super-light in mass. Graupel itself accumulates like ball bearings on the ground and you can roll the pieces around together until they melt (I was doing that just a couple days ago, in fact), but I'm really looking for a description on what the super-light stuff may be... or just confirmation that it's a type of graupel that hasn't been described on Wikipedia yet. – Kerαunoςcopia^◁_galaxies 00:28, 14 May 2010 (UTC)

Actually, I think Graupel is what you are looking for. The heavier ice pellets are called sleet in the U.S. Perhaps the two terms get confused. --Jayron32 01:23, 14 May 2010 (UTC)

Hmm, okay. A case of "right under my nose", then! – Kerαunoςcopia^◁_galaxies 02:01, 14 May 2010 (UTC)

Snow pellets? ~AH1^(TCU) 02:59, 15 May 2010 (UTC)

translate

whats going on in this vid http://www.nothingtoxic.com/media/1273711451/Indian_Cop_Punches_The_Spit_Out_Of_Woman —Preceding unsigned comment added by Tom12350 (talk • contribs) 02:20, 14 May 2010 (UTC)

I think you want the language desk but since you're on the science desk... I observed a caption to the video which stated: "She was there to report domestic violence, and he was just trying to make sure he understood exactly what had happened!" Dismas|^(talk) 04:10, 14 May 2010 (UTC)

geographic centers of population

Where can I find a map with the longitude and latitude of the center of population for the world and for each continent, political divisions, etc. 71.100.0.29 (talk) 06:58, 14 May 2010 (UTC)

Sounds like something that is (or at least based on information available from links at) the center of population article. DMacks (talk) 09:52, 14 May 2010 (UTC)

Bear in mind that continents are not precisely defined.--Shantavira|^{feed me} 13:14, 14 May 2010 (UTC)

Fuel question

we know that the only fuel that work without oxgen is uranium,here is the question how is the hydrogen in the star burn with out oxgen in the space? ex:sun it contain about 74% of hydrogen and 0.77% of oxgen?

thanks for help. —Preceding unsigned comment added by Khaled khallaf (talk • contribs) 09:25, 14 May 2010 (UTC)

Uranium is not the only fuel that works without oxygen. Many things can burn (like a flame) without oxygen, just need something that is chemically like oxygen in the reaction. And nuclear reactions are a totally kind of reaction from chemical ones--the "burning" of hydrogen in a star is nothing like combustion. Both release heat and/or light, but the actual process (and therefore the requirements) are different. The Star#Nuclear fusion reaction pathways section has some of the actual reactions that occur, and you can see exactly what elements are (and are not) required. DMacks (talk) 09:46, 14 May 2010 (UTC)

Uranium releases energy when its unstable heavy nuclei split apart. Hydrogen releases energy when its light nuclei combine. It also releases energy when it is oxidized (e.g. burned) by oxygen. Hydrocarbons are also oxidized by oxygen, as well as food in the human body. Generators release electrical energy when a magnet moves past wire coils. --Chemicalinterest (talk) 12:50, 14 May 2010 (UTC)

There are certainly many 'fuels' that work without oxygen. But you are talking about three very different ways of extracting energy from a 'fuel':

• When you 'burn' things - they react chemically (typically with oxygen - but there are other possibilities) - releasing chemical bond energies between atoms as heat and light. When you burn hydrogen with oxygen, it forms water and releases some heat in the process.
• When you use uranium in a nuclear power plant or a bomb, the energy is released from within the atoms themselves. These very large and unstable atoms simply fall apart, releasing energy in the process (that's why uranium is radioactive) - we do some devious trickery to encourage them to do that more quickly than they would naturally - and we get a LOT of energy out. If you actually set light to some uranium - 'burning it' with oxygen in the conventional sense, then you'd get very little (if any) energy out of it. (Actually, I'm not sure - but you might even have to put some energy INTO it to make it react with oxygen...I'm not a chemist, so I don't know for sure).

Uranium, like most metals, will burn in the conventional sense. See Here. But it releases nowhere near as much energy as if you fission (is that a verb?) it. Buddy431 (talk) 15:37, 14 May 2010 (UTC)

• The hydrogen in the sun produces energy in yet a third way - the enormous gravity of the sun crushes these very small hydrogen atoms together so tightly that they are forced to combine into heavier atoms (helium, in this case) - leaving some left-over bits of atom that are turned into energy. This produces even more energy than messing around with uranium or plutonium. There is a lot of research into creating useful 'fusion energy' here on earth - but it's taking a long time to produce anything useful because it's really difficult to do if you aren't inside a star!

Those three methods of extracting energy are totally different. We really shouldn't talk about 'burning' uranium or hydrogen in those last two cases. What happens with uranium and plutonium is a "fission reaction", what happens with hydrogen in the sun is a "fusion reaction". Talking about the sun 'burning hydrogen' or a nuclear reactor 'burning uranium' is sloppy and confusing - what it's really doing is "fissioning uranium" and "fusing hydrogen into helium". The sun also (albeit much less often) fuses helium into yet bigger atoms - and those into bigger still atoms...and that's how come there is a small amount of oxygen in the sun - it's actually being formed under crushing pressure and vast heat from the hydrogen and helium that makes up much of the sun. SteveBaker (talk) 23:18, 14 May 2010 (UTC)

Mmm. There's a problem of people thinking that they're more different than they really are. For example, a lot of people think that fission and fusion convert mass into energy and ordinary burning doesn't. Really, the idea in both cases is exactly the same: you break and/or form some bonds such that the total bond energy afterwards is less than the total bond energy before. It's just that in one case it's electromagnetic bonds, while in the other case it's nuclear-force bonds. You get more energy from the nuclear force because it's stronger, not because anything fundamentally different is happening. I like the term "nuclear burning" to describe what happens in fission reactors and in the Sun. -- BenRG (talk) 09:54, 15 May 2010 (UTC)

While you are certainly right - one has to tailor the level of explanation to the level of the audience. In this case, our OP is confused and wonders why the sun doesn't need oxygen to burn hydrogen. The detail level of your explanation serves to muddy the waters and confuse still further - is there a difference between a chemical change and a fission or fusion reaction? Hell yes! Not: Well, not really. My explanation answers the question - even if it leaves some small details unstated. That is the art of answering Ref Desk questions. Tell the person what they need to know - don't confuse them with unnecessary complications. SteveBaker (talk) 16:45, 15 May 2010 (UTC)

Spontaneous Generation

When I think about the obsolete theory of spontaneous generation, I have to wonder how any enlightened man at any point in history ever thought this theory to be true. Everyone could see that plants and animals came from other plants and animals (obviously only on the macroscopic level) and that living things NEVER have been observed coming from non-living things. What sort of rationale did people make up in their heads to justify this theory?--160.36.38.182 (talk) 12:48, 14 May 2010 (UTC)

When they saw meat just sitting out rotting with flies flying around it, then maggots "appeared" on it. Instead of studying how the maggots came, they assumed it came from rotten meat. --Chemicalinterest (talk) 12:51, 14 May 2010 (UTC)

Of course, "enlightened men" are spread precariously thin in history (and today). But indeed, before microscopy was invented, on could observe "life" spontaneously springing up from "dead" matter without any visible sign of where it came from. Keeping things sterile enough that no unexpected life crops up is hard enough today, when we understand the processes and necessary hygiene. As evidence, see the various food scandals that crop up over and over again. --Stephan Schulz (talk) 13:02, 14 May 2010 (UTC)

It takes pretty precise work to disprove the theory. You have to be extremely careful that insects do not contaminate your sample before you realize it, because you won't be able to detect their eggs with the naked eye in many cases. Fruit flies are a great example. Leave some fruit out (esp. bananas) for a few days too long. Suddenly you'll have a kitchen full of tiny gnats. Where'd they come from? Did one sneak in when you weren't looking? Or were the eggs there all along? Either way, in a somewhat magical way, you have a huge number of little creatures. When you say that it has "never been observed", that's just tautological — you're saying it hasn't been observed because you know it doesn't happen (and you know that the fruit flies or maggots got there elsewhere). The 18th century natural philosopher would say, "hey man—it's been observed, and it's easy to observe." --Mr.98 (talk) 13:09, 14 May 2010 (UTC)

I can see your point with flys and maggots. But why make up the such things like, for example, that turtles come from rocks when we can see them having sex and laying eggs and the baby turtles coming from those eggs?--160.36.38.182 (talk) 13:16, 14 May 2010 (UTC)

Until Pasteur's work with meat in narrow-necked flasks, the prevailing thought was that life often spontaneously arose, including field-mice from bundles of hay. You'd thought they'd seen other domesticated mammals giving birth and extended it to mice. We have a good article on Spontaneous generation which discusses the history of thought on this. wp:whaaoe CS Miller (talk) 13:35, 14 May 2010 (UTC)

The problem is that you and I are bombarded with TV, Internet, books and journals in huge abundance - and even the least educated person from all but the worst 3rd world countries has been taught at a level far above what someone from the 17th century would have known. For all but the very rich, books were a rare and costly luxury - education was brief and strongly driven by the church - and communications were all-but non-existant. We have microscopes that can see all the way down to individual atoms - they didn't have anything more powerful than a 3x magnifying hand-lens.

You say that we can see turtles having sex and laying eggs - but have you ever seen that in person? I certainly haven't. I've seen it on TV - and I've read about it in books - and was probably taught about it in school...but no, I have never seen any of those things. It's possible that someone who HAS seen it might have told me about it - but that depends on a mobile population and good communications - which certainly didn't exist back then. When most people never strayed more than a day's walk from their place of birth - and only a few percent of people were literate - even true ideas spread very slowly.

The idea of "The Scientific Method" also was only just beginning to come together back then. They had not yet had the idea that you can't just guess that because turtles have hard shells, they must have come from rocks - but instead you have to do some careful experiments before you say that. The whole idea that correlation does not imply causation is actually relatively recent - and it's an idea that the majority of people that I meet still don't understand. If you see a hoard of fruit flies every time you see rotting fruit, it's easy to guess that the fruit somehow caused the flies to come into existence.

You might have seen one of your farm animals or a family member give birth - you'll have seen chickens hatching from eggs - but without the knowledge that all living things are evolved from the same source, how do you know that this also applies to turtles? They certainly look more closely related to rocks than to chickens. Zoo's full of exotic animals belonged only to the very rich - mostly only to royalty. In the 1600's, hardly anyone did long sea voyages - and those that did mostly came back with stories about mermaids and other such stuff.

I think you underestimate the power of information, communication, education and the scientific method. Without those tools, even the smartest people can't reason sensibly about the world they live in.

SteveBaker (talk) 13:48, 14 May 2010 (UTC)

Not to mention that if someone was educated, they look this information up in authoritative works by Aristotle and subsequent great thinkers throughout history. It's hard to argue with that sort of authority. APL (talk) 14:10, 14 May 2010 (UTC)

And the somewhat less enlightened/educated would observe that the bible says that things that lay eggs are birds (I actually have no idea whether it says that...but it wouldn't surprise me - it says that bats are birds) - and arguing against THAT kind of authority could get you burned at the stake. SteveBaker (talk) 14:38, 14 May 2010 (UTC)

I actually have seen turtles having sex, have killed turtles with eggs in them, and have dug up turtle eggs. I have never seen turtles hatching, however. But, believe me, I get your point about the availability of knowledge today compared to then. —Preceding unsigned comment added by 160.36.38.182 (talk) 13:53, 14 May 2010 (UTC)

Sure, YOU may have done - but in a world without the Internet, you couldn't have told me that. If (in 17th century England) I had said that turtles come from rocks - then people may well have believed me because YOU can't tell either me or them that it's nonsense. In reality, you would not even know that I'm telling people that - until some book that I'd maybe written on the subject happened to pop up in a rich man's library someplace where you had the rare privilage to study. Now you could maybe write a book saying that what I said was wrong because you'd seen turtles laying eggs and more turtles hatching from those eggs - and 20 years later, that book might show up in some library that I have access too - but since there are also books there saying that people have seen mermaids and sea monsters big enough to swallow entire ships...why would I believe you? More to the point - why would people that I've convinced even read your book or hear your point of view unless someone tells them about it? If they do hear about it - will they believe your preposterous claim that turtles are really birds because they lay eggs and have flippers like penguins? I don't think so! SteveBaker (talk) 14:36, 14 May 2010 (UTC)

Another point is the level of transport, tourism, leasure time and other things means far more people are likely to have seen in person turtles laying eggs then previously. I don't know where the OP saw turtles (the IP looks up to the US) but there's a very good chance they wouldn't have had the opportunity to watch turtles laying eggs if they were living in the 17th century Nil Einne (talk) 16:39, 14 May 2010 (UTC)

Today we are faced with the opposite problem Count Iblis (talk) 14:03, 14 May 2010 (UTC)

To reiterate Steve's essential point, it's not so much that we have more knowledge today than they had then (we do, but that's beside the point), it's that generally speaking, we're more inclined to take the careful time and effort it takes to validate said knowledge (and have the means to do it). Most writers on what was called "natural history" were compilers of information, not researchers. They would write lots of letters and read lots of books. They would weigh what was said with what made sense to them. Rarely did they have the resources or will to actually do anything like experiments. If someone reliable told them something, they might consider it reliable. If lots of people said the same thing, they thought that was a good indication of its truthfulness. This isn't necessarily a bad approach—Darwin's works are filled with this approach, though he is fairly critical and did indeed like to do his own experiments when he could—but in some cases it definitely led to the case of an elaborate game of "telephone." Add to it that the natural world is strange—would you believe a Platypus existed?—and is full of crazy wonders, and you have what the philosophers would call a very problematic epistemic situation. It's not until the number of people working on these problems in a systematic way grows considerably and communications improve considerably that a lot of the nonsense gets weeded out. (Read: 19th century, when science professionalizes and stops being something that a handful of rich guys do in their spare time.) --Mr.98 (talk) 14:08, 14 May 2010 (UTC)

Certainly if you visit places like the Natural History Museum in London (which has been around for a very long time and has collections dating back to the 1600's) - when you get away from the fancier, modern parts of the museum, you can see that the "scientists" from a couple of hundred years ago were more like stamp collectors than modern scientists. They collected every kind of animal and plant they could - preserved them in jars of formaldehyde or kept the skeletons or used taxidermy to preserve their outer appearances - and they'd make beautiful drawings of their anatomy. But that's about where it stopped. At the natural history museum - you can see cases and cases of butterflies and beautifully posed stuffed birds and such like - but almost nobody from that time was doing any reasoning about what they'd collected. They categorized and preserved - but it was quite literally just like stamp collecting. SteveBaker (talk) 14:25, 14 May 2010 (UTC)

The OP has no grounds for their bewonderment. Large numbers of people today think that a spontaneous generation of living things occurred either in an Abiogenesis event or literally as related in a creation story, and they are almost all regarded as enlightened by their friends. Cuddlyable3 (talk) 14:21, 14 May 2010 (UTC)

If, to all appearances, organisms seem to 'generate spontaneously', well why not just go with that until proved differently? There's no use fretting over these things when there simply isn't any evidence to the contrary. Vranak (talk) 14:39, 14 May 2010 (UTC)

Enlightened persons of the 18th and 19th century had seen weevils appear in a sealed container of flour, or other tiny living things appear in materials which had apparently not been accessible to small living creatures. (I have found this to happen, even when the plastic container of flour has been sealed with an apparently airtight lid for months. I "know better", just as I "know" that my senses deceive me when it appears that a magician can make things appear and disappear). Scientists even of the mid 19th century tried boiling sealed flasks with hay infusion, and found that some microscopic life grew in it and it became cloudy and smelled bad. It turned out that it is hard to sterilize hay infusion, compared to broth, and that "boiled" is not necessarily "sterilized." What microscopic fraction of the adults of 1830 had ever seen some of the phenomena we think are "everyday knowledge" from watching nature programs on TV, which distill thousands of hours of observation and filming into a few seconds of "common knowledge" of how little animals reproduce? In the 20th century when I was about 5 someone told me that a horse hair placed in water would become a little "hair snake" and I immediately tried the experiment, with negative results. Not everyone has the inclination, time or resources to try and replicate experiments or observations that are "common knowledge." Edison (talk) 15:14, 14 May 2010 (UTC)

new elements

Is there any possibility of discovering one or more new elements that are stable (at least with a half life measured in years rather then ms)? Googlemeister (talk) 14:26, 14 May 2010 (UTC)

Yes! Very much so. See Island of stability - very recently, a synthetic element was made that is fairly stable compared to other massive elements. However, what doesn't seem likely is that any such elements will be found in nature...if they were there, I'm pretty sure we'd know it - unless maybe they only exist in 'exotic' places like the hearts of stars or something. SteveBaker (talk) 14:42, 14 May 2010 (UTC)

Or in the detritus left over after supernovae. --Mr.98 (talk) 15:41, 14 May 2010 (UTC)

Everything past iron only exists in the detritus of a supernovae. Of course, these elements may have half-lives short enough that there's none left by the time it forms into part of a planet. — DanielLC 01:18, 15 May 2010 (UTC)

Not quite. Heavier elements can be formed in stars via the S-process; approximately half of the heavier-than-iron matter in the universe is believed to be formed this way. And heavier elements can leave a star by means other than supernovae: novas and the rarer luminous red novas.--Atemperman (talk) 05:11, 17 May 2010 (UTC)

No! The Island of stability indicates only the stability against beta decay and alpha decay, spontaneous fission is not plotted in that chart. There might be elements out there with a half life of hours for beta decay and alpha decay, but they will undergo spontaneous fission in miliseconds. If the theories about the atomic nucleus are right it is very unlikely to find any elements with a significant half life.--Stone (talk) 17:34, 14 May 2010 (UTC)

Our article does claims some people suggest millions of years is a possibility sourced to [6] Nil Einne (talk) 00:39, 17 May 2010 (UTC)

ant

When a queen ant lays her first egg, it's tiny. How does it grow bigger and into a cocoon and then an ant without any feeding? Because the queen ant lives alone in her newly dug nest and doesn't eat or drink for months until the baby ants hatch and bring her food. —Preceding unsigned comment added by KELITORPO (talk • contribs) 15:09, 14 May 2010 (UTC)

Individual ants store food in their crops and pass it to larvae via Trophallaxis. This is explained at Ant#Development_and_reproduction. Zain Ebrahim (talk) 15:40, 14 May 2010 (UTC)

The queen initially feeds the first ants using food manufactured from her own fat stores and the metabolism of her wing muscles (she no longer needs them). The first batch of baby ants are exceptionally weak and feeble, just enough to start things up. (I don't think this takes months.) Check out E.O. Wilson's engaging (fictionalized) account of this ("Trailhead") from a recent New Yorker. --Mr.98 (talk) 15:46, 14 May 2010 (UTC)

re:donkeys

I know that a male donkey is a jack, and a female is a jenny, or jennet... What do you call a gelded donkey. A gelded horse is a gelding, for example. Thanks Gqe9670 (talk) 17:50, 14 May 2010 (UTC)

Our article Gelding says that it can be used to apply to donkeys as well. Vimescarrot (talk) 18:21, 14 May 2010 (UTC)

Medical Breakthroughs

Have their been any diseases cured or medical breakthroughs in the past ten years? Why haven't we cured aids or malaria yet? Where are the results of stem cells and gene threapy that have a few years away for over a decade?! TheFutureAwaits (talk) 22:47, 14 May 2010 (UTC)

Malaria actually is curable, it's just that the majority of those who have it can't afford the treatment. AIDS will probably never be cured, it will require social changes to stop its spread. Gene therapy is still being worked on, it has had some successes, but is also dangerous which slowed research. Stem cell treatment was never just a few years away, it has just been massively politicized. People who support abortion did not want any restrictions that might lead to bans on abortion, so they made tons of pie in the sky promises about stem cell therapy to try to drum up support. And googling "medical breakthroughs" found tons of articles with a large variety of lists. Ariel. (talk) 23:48, 14 May 2010 (UTC)

We make medical breakthroughs all the time, new drugs with better efficacies and fewer side effects. There are certain diseases which continue to elude us, the big one being HIV/AIDS. We haven't found a way to cure it yet because it happens to destroy the one thing our body needs to get rid of it. The only currently percievable way to get rid of HIV is to prevent all infected partners from having sexual intercourse with anyone who isn't infected--a task inconceivable beyond imagination. Our only hope is that some day researchers will find a revolutionary breakthrough in the way our immune systems works, or with a drug which can target the virus and kill it and prevent it replicating inside our own cells. Regards, --—Cyclonenim | Chat  00:01, 15 May 2010 (UTC)

I will note that HIV infection is in many cases treatable, though not generally considered curable. Where HAART is available, the average expected time to progression from HIV infection to full-blown AIDS is now more than thirty years(!) There are tantalizing hints of future curative therapies, however. CCR5 is a receptor protein expressed on the surface of immune system T cells. It's been known for a while that a small fraction of the human population is innately immune to HIV infection, because those people carry a mutation in the CCR5 protein; this mutation – CCR5-Δ32 – prevents entry of the virus into T cells. A number of companies now have drugs in the pipeline which are designed to bind to CCR5 and thereby prevent cell-to-cell transmission of HIV, ultimately curing the disease. Last year a clinical gene therapy trial began, in which the CCR5 gene was to be knocked out in HIV-positive patients. Finally, in 2008, a German HIV-positive leukemia patient (which would normally sound like a cruel medical joke) was cured of both conditions by bone marrow transplant from a donor who carried the mutant CCR5. (The risks of bone marrow transplantation are rather high, and the donor pool is limited, so this particular therapeutic approach is unlikely to be adapted for individuals who aren't receiving such a transplant for other reasons.) I'll let the OP decide which, if any, of those approaches might constitute a 'breakthrough'. TenOfAllTrades(talk) 02:17, 15 May 2010 (UTC)

See SuperAIDS. There have been many advancements in treating cancer, for example DCA and Madagascar periwinkle but no complete cures or breakthroughs. ~AH1^(TCU) 02:54, 15 May 2010 (UTC)

Whee, statistical and disease-progression projections! "Where HAART is available, the average expected time to progression from HIV infection to full-blown AIDS is now more than thirty years(!)" AIDS wasn't even known 30 years ago, HIV as the infective agent wasn't discovered until a few years later, and the first retroviral wasn't approved for HIV/AIDS until several years after that. Average 30-year expectation for something that's only been around 24 years? DMacks (talk) 16:37, 15 May 2010 (UTC)

The figure is actually closer to twenty years. [7] Regards, --—Cyclonenim | Chat  01:39, 16 May 2010 (UTC)

acetic acid

which is stronger 5% acetic acid or 10% sulfuric acid —Preceding unsigned comment added by Tom12350 (talk • contribs) 22:52, 14 May 2010 (UTC)

10% sulfuric acid; it's a strong acid. 5% acetic acid is what household vinegar typically is. -- Flyguy649 ^talk 23:22, 14 May 2010 (UTC)

yes but white vinegar is pretty strong and 10% sulfuric acid is a very dilute solution —Preceding unsigned comment added by Tom12350 (talk • contribs) 23:32, 14 May 2010 (UTC)

No. Vinegar is 5% acetic acid. (Acetic acid is a weak acid). A 5% sulfuric acid solution (~1M) has a pH of 0.3 while a 5% acetic acid (i.e. household vinegar) has a pH of ~2.4. There are loads of google refs for these figures. -- Flyguy649 ^talk 23:34, 14 May 2010 (UTC)

You need to explain what you mean by "pretty strong" here. "Strong acid" has a specific meaning (see the link Flyguy provided). However if you're simply looking at dilution (which makes no sense when talking about acid "strength") a 10% solution of something is self-evidently twice as "strong" as a 5% solution of something, so what are you asking? Please clarify your question. Tonywalton ^Talk 23:40, 14 May 2010 (UTC)

The Vinegar smells stronger than the sulfuric acid though. Graeme Bartlett (talk) 23:51, 14 May 2010 (UTC)

I don't know about that. At sufficient concentrations, sulfuric acid fumes, and its quite acrid smelling. But a 5% acetic acid solution will only have a pH of 4 or 5 or so (pH = -log (SQRT (Ka * molar concentration)) for anyone that wants to calculate). As a strong acid, a 10% sulfuric acid solution will have a pH probably much closer to 1 or 0. --Jayron32 00:12, 15 May 2010 (UTC)

Carboxylic acids tend to have strong odors. Did you ever smell butyric acid? --Chemicalinterest (talk) 00:21, 15 May 2010 (UTC)

when i wash a surface with vinegar unless i rinse it well it still smells like vinegar and has a acidic feeling to it when it dries. so it leaves a residue when it dries. does 10% sulfuric acid also leave a residue when it dries? —Preceding unsigned comment added by Tom12350 (talk • contribs) 01:46, 15 May 2010 (UTC)

The sulfuric acid will get more and more concentrated, and then absorb water. Eventually it should all evaporate over time. Graeme Bartlett (talk) 12:39, 15 May 2010 (UTC)

10% sulfuric acid probably wouldn't evaporate very quickly, since sulfuric acid has a strong attraction for water. Acetic acid probably precipitates out of the solution when a surface with it on it is dried. BTW, you can wash it with sodium bicarbonate solution to remove odors of any acid, or even the odor of ammonia. --Chemicalinterest (talk) 14:24, 15 May 2010 (UTC)

May 15

Magnetic powder

I have a magnetic powder that doesn't dissolve in acid. It is formed when ferrite magnets dissolve in hydrochloric acid, leaving a spongy insoluble magnetic residue behind. When dried, it is a powder. What is it? --Chemicalinterest (talk) 00:22, 15 May 2010 (UTC)

Iron? --Jayron32 01:36, 15 May 2010 (UTC)

One of these perhaps? The iron would have gone I think. --BozMo talk 07:22, 15 May 2010 (UTC)

Could be nickel, it's pretty resistant to acid attack. FWiW 67.170.215.166 (talk) 07:30, 15 May 2010 (UTC)

Thanks. It isn't iron, because it would have dissolved (and it looked like it didthe iron in the magnet did). Nickel dissolves, albeit slowly (I had the magnet in acid for 2 weeks). It might be some of the ferromagnetic compounds that does not dissolve in acid. I don't know which one it is. And by the way, it is unaffected by sodium hypochlorite. --Chemicalinterest (talk) 11:30, 15 May 2010 (UTC)

Are you able to do a borax bead test? You need a block of charcoal, borax and a blowtorch. This can give a good clue as to content of a mineral substance. Graeme Bartlett (talk) 12:24, 15 May 2010 (UTC)

No, I do not have charcoal or a blowtorch. I only have borax. Thanks anyway. --Chemicalinterest (talk) 12:51, 15 May 2010 (UTC)

Activated charcoal is readily availible, you can probably find it pretty easily if you look, if you are willing to wait a few days you can get it on the internet. Blowtorches are pretty cheap; you can get a small propane canister and a torch nozzle for it for a very reasonable price at your local supermegagigantohardwarestoreandlumberyard Depot. --Jayron32 13:21, 15 May 2010 (UTC)

They might not want an amateur chemist who is just out of 11^th grade to buy the blowtorch. --Chemicalinterest (talk) 14:25, 15 May 2010 (UTC)

I know a girl of that age who bought one to make Creme Bruleé. Kids that age routinely take a welding course in high school. Edison (talk) 19:32, 15 May 2010 (UTC)

I can't imagine anyone would care if you bought a simple torch. We aren't talking about an acetylene welding torch; a simple propane torch is cheap, easy to operate, and relatively safe if you are careful. You don't need to provide identification to buy one; just walk in and pay for it. No one is likely to bat an eyelash over it. And if you are woried, have your parent pick one up for you. You could also probably order one by mail from the internet as well. I just looked on Google, and they're selling Bernzomatic pencil torches for $11-20 dollars, depending on where you buy it. The canister of propane is sold seperately, but they have small canisters, probably a quart to a half gallon size or so, for not much more than that. --Jayron32 00:34, 16 May 2010 (UTC)

In a science kit I had it said you could do borax bead tests with a paper clip and borax. Heat the paper clip, then dip it in borax. Melt the borax, dunk it in the chemical, and heat it again. Cool it, and the color should be there. It doesn't seem to work that well though. --Chemicalinterest (talk) 18:49, 16 May 2010 (UTC)

which would be worse

Would an ice age or a hot/warm age be more damaging for the world at this point in time? 71.100.0.29 (talk) 01:55, 15 May 2010 (UTC)

It's hard to say unless we know what factors you would take into account in defining damage. That said, an ice age would be more fun. DuncanHill (talk) 02:00, 15 May 2010 (UTC)

It's probably safe to say that any drastic climate change within a human lifetime would be damaging for the global population. Based on latitude, an ice age would mostly impact the rich, while a hot house would mostly impact the poor. As for extant species, warming would likely be more damaging as the recent Pleistocene climate consisted of ice ages and not hot houses. ~AH1^(TCU) 02:49, 15 May 2010 (UTC)

It depends if you are a sun person or a shade person. Vranak (talk) 02:59, 15 May 2010 (UTC)

An "ice age" would leave vast areas unsuitable for agriculture and (eventually) covered in ice hundreds of feet thick. On the other hand, an overall increase in temperature will also affect agriculture because of shifting weather patterns, pests and pathogens, rising sea level, etc -- all the global warming effects that are being well documented now. BTW, we are barely out of an "ice age," although in a period without active enlargement of glaciation. 72.148.152.214 (talk) 20:08, 15 May 2010 (UTC)

Technically we are still in an ice age, there is ice all year round at the poles. We are in an interglacial period. Any significant change in global temperatures, whatever the direction, would be very bad for agriculture. Our current crops have evolved and been actively selected to grow well in whatever climate they are grown in. Any change in those climates will stop the crops growing well. Even though there may be places that still have reasonable temperatures, that won't help. If global temperatures drop, the tropics may still be warm enough to grow crops, but all our crops that grow well in those temperatures have evolved to work well at high latitudes with short growing seasons containing very long days, they won't grow as well in non-seasonal climates with 12 hour days. If global temperatures rise, the poles may be cool enough to grow crops, but will have 24 hour days during the growing season and we don't have crops that have evolved well to grow under such conditions. --Tango (talk) 00:41, 16 May 2010 (UTC)

Just to clarify, the sugar industry has evolved along the lines of two separate crops. One works well at about 20 and the other at about 50 latitude. One is sugar cane and the other is sugar beets so sugar is one crop that is more or less protected from climate change. 71.100.0.29 (talk) 02:40, 16 May 2010 (UTC)

My point applies just as well to sugar cane and sugar beets as to any other crop. There being two different crops with high sucrose content doesn't make any difference to what I was saying. --Tango (talk) 08:47, 16 May 2010 (UTC)

Swima bombiviridis - article in Science

I need the above article. Does anyone have it? Very grateful for answers

/Jonte93 (talk) 02:57, 15 May 2010 (UTC)

Unfortunately, Wikipedia's article on that topic (which can be found at Swima) is very meagre. You can look at the sources cited or search Google. Intelligentsium 03:01, 15 May 2010 (UTC)

Here is a search for Swima bobiviridis at the Science website which found 1 article. You'll need an institutional/personal subscription to read it. This is a link to the abstract. It may be possible to email the authors for a copy (email on the abstract page). -- Flyguy649 ^talk 12:50, 15 May 2010 (UTC)

The above article "Deep-Sea, Swimming Worms with Luminescent "Bombs"" can be read online via one of the authors homepage [8] - just find it under publications, and click it. --Kim D. Petersen (talk) 13:48, 15 May 2010 (UTC)

Found it! Many thanks

/Jonte93 (talk) 17:48, 16 May 2010 (UTC)

Nazi decompression experiments

Some years ago I read a rather grisly account of some high altitude simulation experiments that were run on prisoners in WWII-era Germany. However, neither a cursory search of Google nor Wikipedia has been able to uncover the level of detail I was looking for. I recall that at least one of the victims clawed at his temples to balance his gaseous equilibrium or some such. But there is no such account on the internet now, that I can see. Does anyone here know of site that has this information? Thanks. 70.70.149.172 (talk) 05:29, 15 May 2010 (UTC)

Seems like Nazi human experimentation#High altitude experiments would (or should, if it doesn't and you can find info). DMacks (talk) 06:40, 15 May 2010 (UTC)

Not exactly a wealth of detail, that. Perhaps google is the only hope. --203.22.236.14 (talk) 11:31, 15 May 2010 (UTC)

I thought the Japanese did something like this as well, with prisoners placed in decompression chambers and essentially killed in somewhat tortuous ways. But I too was never able to find much info on it here or on Google. I suppose the library would be the best place to start. – Kerαunoςcopia^◁_galaxies 07:43, 16 May 2010 (UTC)

The Japanese in WW2 were more into chopping the heads off prisoners of war, beatings, disemboweling, bamboo shoots under fingernails, eyes gouged out, thumbscrews, waterboarding. The Germans did the "medical experiments," as opposed to routine medieval torture of prisoners, like the U.S. has done recently. Edison (talk) 22:07, 16 May 2010 (UTC)

67.170.215.166 (talk) 02:39, 17 May 2010 (UTC)

Coat colour of wild mice

Is it possible to find coat colours other than brown/agouti in wild populations of mice? Are there any wild populations of black mice? 69.181.157.95 (talk) 05:47, 15 May 2010 (UTC)

Melanism is common in some wild populations of rodents (Rock pocket mouse and Eastern grey squirrel come to mind), but I never heard of completely melanistic Mus sp. in the wild. That does not mean they don't exist, of course. Some house mice have fairly dark coat, but the belly is usually of a light color. Fancy mice can be completely melanistic, but those are deliberately bred mutant mouse lines. Bear in mind, however, that there is a very large number of ways in which Mc1r or several other genes that are involved in coat color regulation may (and will) spontaneously mutate. Some of those mutations result in melanism. The question is, how beneficial a particular mutation would be in the wild, and what are the chances that it will propagate in the population. So there certainly may be black mice out there in the wild somewhere. I've never heard of a known population of melanistic Mus sp. in the wild, though. Hope this helps. --Dr Dima (talk) 08:31, 15 May 2010 (UTC)

Trigger point article needs help.

Someone who knows about muscle pathology should take a look a the trigger point article. It appears to be partially reworked to be neutral and balanced near the beginning, but there seems to be a lot of OR/poorly substantiated claims being given undue credibility in the body. -Craig Pemberton 07:04, 15 May 2010 (UTC)

The discussion page on WP:Medical may be a good place to post your comment. --Chemicalinterest (talk) 12:48, 15 May 2010 (UTC)

Thermal Wallpaper

Okay, so I am after gut reactions to "plausibility" of a claim. I live in a house with 13.5 inch solid brick walls with no potential for exterior insulation or cavity fill, but even in the middle of winter it is generally only heated in the evenings (thats not uncommon in England: I grew up in an unheated house). I am looking at thermal wallpaper which is 3.5mm thick and fire rated. On a straight k value steady state basis this would reduce the heat loss through the walls by about 25% but the "claim" is that this impact is greatly increased by three effects (1) that houses are not steady state, they have intermittant heating and by putting this paper on the inside of wall and partly decoupling the thick walls from the rooms you can decrease warm up time and decrease the time after heating is off when your heat is still being lost to the outside world (2) during the warm up period (of say two hours to get to full steady state) the liner means the surface temperature of the wall is significantly closer to ambient giving rise to a marked reduction in convection and convective heat transfer to the wall on top of the decoupling effect and (3) the warmer wall surface during the cycle makes people feel noticably warmer because black body radiation from walls is a significant part of perceived heat. So which of these do we believe and how significant might they be? In particular if 25% is achievable steady state what might be achieved if 50% of the heating is done whilst the rooms are warming? --BozMo talk 07:18, 15 May 2010 (UTC)

You don't say whether your heater works by convection or radiation. Claims 1 - 2 - 3 are not false but if heating by convection the thermal inertia of the air mass dominates the warming time so 1 & 2 are not very significant. If your heater radiates then the subjective effect 3 is also insignificant. I don't see much increase over the 25% k factor which gives you faster warming to steady state. As you are interested in economy you will have a thermostat to hold the temperature at your minimum comfort level so slower cooling will not extend your comfortable time. Cuddlyable3 (talk) 12:48, 15 May 2010 (UTC)

Convection, but you are seriously trying to tell me that 25kg of air has more thermal inertia than 50 tonnes of bricks? --BozMo talk 15:54, 15 May 2010 (UTC)

As long as the wallpaper goes on the ceiling as well (if ceiling uninsulated) there would be an improvement. But the heat obtained from heating your house will on stay only "a bit" longer e.g 5 degree drop over one hour instead of 10 minutes. Usually checking for air flowing through the house is first priority, then ceiling insulation, then walls and windows. The air on the house would heat up much quicker with the wallpaper. The difference between no insulation and some is noticeable; much more than the difference between some and a lot of insulation. What is the R-value of this wallpaper? Polypipe Wrangler (talk) 01:27, 16 May 2010 (UTC)

Aerogel is now cheap enough to be used for insulation it's still more expensive than normal insulation, but if you have the budget for it, it would be ideal for your situation. Ariel. (talk) 02:06, 16 May 2010 (UTC)

The roof is seriously well insulated. The wall paper (Wallrock) basically seems to be the German version of aerogel, and it has a list price of about $100 a roll. There are too many different units to convert them and give you an R value. The 25% is correct by the time you have recipricaled on a wall. Air flow is complicated because we burn a lot of wood and the walls are all breathable etc. --BozMo talk 08:11, 16 May 2010 (UTC)

Wallrock is most definitely not aerogel. Wallrock is some kind of foam, PVC foam I think. It's got decent insulation, but it doesn't come anywhere near aerogel. List the units here in their original form, someone might be able to convert it to an R value for you. But call the aerogel people and see if the price is in the realm of possible. (They don't list the price on their website, so it's probably high - but it might be worth it, depends on how much heat costs you.) Ariel. (talk) 10:27, 16 May 2010 (UTC)

Also, as far as their claim that the room will "feel" warmer - they are totally right. Humans do not experience temperature in the same way that a thermometer does. A thermometer measures absolute temperature, humans measure the difference in temperature (humans measure the rate of heat gain/loss from skin, not the actual temperature of the environment). If the walls of a room are warm, but the air is cold, you will still feel warm because of the infrared light from the walls. And the opposite too - you can have a warm room (at least the thermometer says it's warm), but with cold walls you will feel cold. The traditional solution was tapestries. Ariel. (talk) 10:27, 16 May 2010 (UTC)

solid friction factor in pneumatic conveying

hi

does anybody know a good correlation to get a reasonably accurate solid friction factor for dilute phase flows of reasonably fine particles?

thanks —Preceding unsigned comment added by 125.17.148.2 (talk) 07:21, 15 May 2010 (UTC)

bulk density vs product density

hi Is there any way to measure/calculate the product density of fine particles as opposed to the bulk density? thanks —Preceding unsigned comment added by 125.17.148.2 (talk) 07:38, 15 May 2010 (UTC)

Some particles may be finer, which means that air is interspersed between the particles, making them lighter. I don't know of any other way other than taking a known volume (1 cu. in. or cm³), weighing it, and figuring out the density. --Chemicalinterest (talk) 14:28, 15 May 2010 (UTC)

A harder way may be to measure how much air is between the particles. In an air tight container, find how the pressure varies with a small change in volume, Using the gas laws you can work out the volume of air, and then the difference is the volume of particles. If the particles are embedded in something else, you may be able to take a series of cross sections and total the area of the sliced particles to get a a fraction of the volume occupied. (sorry getting off track here). A better way will be to get one particles, weigh it accurately and measure its volume precisely, which may not be easy. Graeme Bartlett (talk) 23:27, 15 May 2010 (UTC)

If the particles or powder are insoluble in water or another suitable liquid, see Buoyancy for a method. Cuddlyable3 (talk) 12:04, 16 May 2010 (UTC)

Doing exercises - general question

Hello, Friends. I have a general question which is kind of scientific. When doing exercises (any type of, sit-ups, or using thera band or whatever), what is the difference between doing them with more load/resistance but fewer repetitions, or less load/resistance and more repetitions? And an additional question, what is the difference between doing (such) exercises faster or slower? This is not a homework question, even if my girlfriend is a physiotherapist, just curiosity. Cheers and thanks, Ouro (blah blah) 10:26, 15 May 2010 (UTC)

Not a "science" answer, but... I was about to type something like "high resistance/weight, low reps gives improved power; lower resistance, higher reps improves endurance/strength". But then I realised that (a) I'm not sure of the correct terminology and (b) I'm using a command line browser and can't be bothered googling it. So in short - body builders tend to use high weight, low repetition (greatest weight they can lift for about 3 to 6 reps). General weight training for "normal" people looking for better fitness is 15 to 20 reps of a weight they can do 3 sets of that number of reps. --203.22.236.14 (talk) 11:43, 15 May 2010 (UTC)

There are two classes of exercise: anaerobic exercise and aerobic exercise. Aerobic exercise is like walking, jogging, etc.: something that you do repetitively but doesn't require much strength. Anaerobic exercise is like pushups, pullups, situps, etc.:something that requires more strength. Both have their benefits. Aerobic exercise strengthens your heart and lungs, and helps your circulation. It makes you have more endurance. Anaerobic exercise improves your muscle size and tone, which is the hardness of your muscle. A balance of both is best. --Chemicalinterest (talk) 12:46, 15 May 2010 (UTC)

I think we're talking only about different types of anaerobic exercise here. The general story as I understand it is that it is possible to differentiate strength from endurance -- strength is determined by the number of muscle fibers, endurance by the amount of energy available for each fiber. Maximizing load is best for increasing strength (and muscle size), maximizing reps is best for increasing endurance. Looie496 (talk) 16:41, 15 May 2010 (UTC)

The articles seem to suggest that you are right, Chemicalinterest. I'd like to hear more responses, though what You guys wrote up to now does indeed clear things up a notch already. --Ouro (blah blah) 07:40, 16 May 2010 (UTC)

mind control

Some have suggested that one reason pot should be legalized is that it is an effective means of greed control. Does pot control greed and is it the answer to preventing sale of tainted goods by Chinese manufactures and was this the purpose of the British imposing the sale of opium on China? 71.100.0.29 (talk) 13:50, 15 May 2010 (UTC)

I don't even know where to begin with this one. Tommy2010 13:52, 15 May 2010 (UTC)

Okay let me inject an example: Some say that pot destroys a woman's natural inhibition to allow anyone to see their nude body in our (former) culture or having casual sex. Give a girl pot and this natural inhibition is forgotten or wiped away. In fact that is why they call it Mary Wanna. 71.100.0.29 (talk) 16:12, 15 May 2010 (UTC)

You are 100% wrong about why the British forced Opium on the Chinese. Read our article Opium Wars which describes what happened in great detail. The bottom line is that the European market wanted Chinese Tea, Silk and Porcelain - and the only goods they had to trade that the Chinese merchants actually wanted was silver and opium. Since silver was highly valued in Europe, and opium was dirt cheap to grow and process, the obvious thing for the British merchants to do was to push opium into the Chinese market. However, the Chinese government (wisely) banned that activity and cracked down hard on smugglers. In an ideal world, that would have been the end of it - and those valued Chinese goods would have risen in price and been paid for in silver. Sadly, what actually happened was that the British government were persuaded that "free trade" was important and there were a series of ugly wars about the opium trade. It certainly wasn't about "mind control" - it was pure, uncontrolled greed on the British side of things. SteveBaker (talk) 16:33, 15 May 2010 (UTC)

Why not socks or other great stuff Brits are famous for making that the Chinese wanted - even raw materials like the Japanese? Why opium? 71.100.0.29 (talk) 17:11, 15 May 2010 (UTC)

You'll have to ask the Chinese why they'd prefer Opium over socks.

Most statements about cannabis's effect on personality are either prohibitionist myths or, at best, poorly researched. I've heard that it makes people lazy, and that it also makes them violent. I've also heard that it drives people to satanic Jazz music and makes white women want to seek sexual relations with Negroes. — Ƶ§œš¹ _{[aɪm ˈfɹ̠ˤʷɛ̃ɾ̃ˡi]} 17:51, 15 May 2010 (UTC)

Well the truth is that drugs do eradicate inhibitions and that some men know this and have no problem supplying women with drugs in exchange for tapping their honeypot. Its not a case of race or anything else except the loss of social and/or cultural inhibition and the reason why decent people are against the use of drugs and scoundrels are in favor of using it. 18:28, 15 May 2010 (UTC) —Preceding unsigned comment added by 71.100.0.29 (talk)

Drugs eradicate inhibitions? Do you have source for such a sweeping statement? — Ƶ§œš¹ _{[aɪm ˈfɹ̠ˤʷɛ̃ɾ̃ˡi]} 20:58, 15 May 2010 (UTC)

www.xnxx.com, www.tube8.com, www.xhamster.com, www.slutload.com, www.clipdump.com, Weeds © 2009 Lions Gate Television Inc. All rights reserved. Trademark, Copyright and Terms. —Preceding unsigned comment added by 71.100.0.29 (talk) 22:19, 15 May 2010 (UTC)

Those are porn sites. That really isn't a source that we are looking for an answer. sources from Medical doctors would be nice. wiooiw ^(talk) 22:35, 15 May 2010 (UTC)

Where is your source that these are all porn sites?—Preceding unsigned comment added by 71.100.0.29 (talk • contribs)

Where exactly are you taking this. The websites clearly say "Free porn". wiooiw ^(talk) 22:44, 15 May 2010 (UTC)

Our gym has a sign that says free porn. So what? Besides, you are the one who is trying to take this somewhere. —Preceding unsigned comment added by 71.100.0.29 (talk) 22:46, 15 May 2010 (UTC)

Well there's greed, then there's greed. And Henry Hazlitt thoroughly examined the Foundations of Morality and concluded that rational self-interest, aka greed, is a very profitable and positive characteristic indeed. Basically, it's because each person knows best what will profit them, so they should go after that without delay. To 'sacrifice' one's desired outcomes for the sake of 'getting along with others' is a frankly wrong-minded and self-defeating approach. Vranak (talk) 23:05, 15 May 2010 (UTC)

An oxymoron: suppose one's desire is only to do right and 'get along with others' like Budda or Jesus Christ (or love one another in the case of Jesus Christ)? 71.100.0.29 (talk) 00:57, 16 May 2010 (UTC)

Yes, but it is naive to think that everyone is driven by prospects of peace. Many people seek zesty recognition from others, and will not let silly things like 'morality' and 'correctness' stand in their way. It is in their fundamental nature, peace be damned. See Year of the Dragon, Year of the Tiger, Year of the Monkey, Year of the Ox, etc etc etc. Vranak (talk) 01:24, 16 May 2010 (UTC)

Its called Karma. 71.100.0.29 (talk) 02:10, 16 May 2010 (UTC)

"Pot" usually means cannabis. That is a completely different drug to opium. Why would you think that something you have heard about cannabis would explain the opium wars? --Tango (talk) 00:58, 16 May 2010 (UTC)

Make a list of the things each drug is used for. 71.100.0.29 (talk) 01:12, 16 May 2010 (UTC)

Stop trolling. You've already got a discussion going above about cannabis, this is clearly some sort of personal endeavor against it. Regards, --—Cyclonenim | Chat  01:42, 16 May 2010 (UTC)

And just how would trolling help my cause? 71.100.0.29 (talk) 02:07, 16 May 2010 (UTC)

• In the medical marijuana discussion Viriditas made a comment about greed being responsible for Chinese scandals; suggesting that greed could be eliminated if people smoked pot. 71.100.0.29 (talk) 06:10, 16 May 2010 (UTC)

• I made no such ridiculous suggestion, and any such a claim is absurd. Either you didn't understand what was said or you are trolling. I leave it to the reader to decide. Viriditas (talk) 06:53, 16 May 2010 (UTC)

Sounds like both of you are trying to pick a fight in support of using medical marijuana for mind control but this is the first time I have encountered a tag team trying to label a discussion they are not going to win as trolling. I think your motives are suspect and transparent and that both of you must use pot. 71.100.0.29 (talk) 09:45, 16 May 2010 (UTC)

Then you are an idiot. As you can clearly see above, I'm arguing against the use of cannabis. Stop trolling. Regards, --—Cyclonenim | Chat  14:38, 16 May 2010 (UTC)

do people in different inertial frames agree what time it is?

nt —Preceding unsigned comment added by 84.153.204.221 (talk) 14:08, 15 May 2010 (UTC)

Not in general - no. SteveBaker (talk) 16:21, 15 May 2010 (UTC)

It's almost as easy for people in different frames to agree on time as for people in the same frame. Their clocks run at different rates, but since it is easy to predict what rate somebody else's clock runs at (if you know their velocity), it isn't difficult for one to know the time that will be assigned by the other to a given event. In other words, it is always possible to choose one observer as "reference", and to come to an agreement that the time recorded by the reference observer is the "official" time, which everybody will use. Looie496 (talk) 16:53, 15 May 2010 (UTC)

But in special - yes? For any gravitational fields? 84.153.204.221 (talk) 18:51, 15 May 2010 (UTC)

Well on the earth, in a non inertial frame, clocks run at different rates at different heights. The time is close, but not exactly the same, and does shift at different rates. See gravitational time dilation. Graeme Bartlett (talk) 23:15, 15 May 2010 (UTC)

I don't think Steve meant "In General Relativity...", he just meant "Generally speaking...". General Relativity doesn't really have a concept of inertial frames, so your question only really makes sense in Special Relativity. --Tango (talk) 00:54, 16 May 2010 (UTC)

Swan mom throws away eggs

That's right, a swan mom nesting on a raft in the middle of the pond pushed an egg out of the nest. It it still there on the wooden deck while apparently she has others still in the nest. Did she know the egg was dead or sterile, or is it a reaction against overbreeding, or she just had a bad day? The other pair nesting in the same pond seems fine. East of Borschov (talk) 14:42, 15 May 2010 (UTC)

Was it definitely a swan's egg? There are plenty of birds which lay into other birds nests... --BozMo talk 18:29, 15 May 2010 (UTC)

Sure. It was big. There are no geese or anyone comparable in size around. East of Borschov (talk) 21:25, 15 May 2010 (UTC)

I've read that many species will reassess according to their resource how many offspring they can feed and will act accordingly. I'm not surprised due to the behaviors of birds like the coo coo and the bird of paradise. 71.100.0.29 (talk) 18:41, 15 May 2010 (UTC)

Have you had a chance to take a close look at the egg? Maybe it was cracked? --Kurt Shaped Box (talk) 21:31, 15 May 2010 (UTC)

At twenty meters distance it looked ok. East of Borschov (talk) 21:47, 15 May 2010 (UTC)

Oh yeah - of course, she'd really try to hurt you if you went up to her nest, wouldn't she? Silly me. :) Just a thought - is it possible that another human has been interfering with her nest? I know that mother birds will sometimes freak out and discard/destroy eggs (or just abandon the nest completely) if they notice that it's been disturbed. --Kurt Shaped Box (talk) 22:18, 15 May 2010 (UTC)

These are captive swans, they get along with their caretaker for years. So unless some idiot swam into the pond... East of Borschov (talk) 22:28, 15 May 2010 (UTC)

Suffice to say, the mother was of a low opinion that this egg would ever become anything worth having around. Vranak (talk) 22:52, 15 May 2010 (UTC)

I'm not sure one unsourced, unexplained opinion about a swan you've never met would actually suffice anything for most people. Vimescarrot (talk) 16:48, 16 May 2010 (UTC)

snakes and lizard

In cambodia, there lives a lizard which depends on snakes to eat its liver, if not the liver will choked the lizard and the lizard dies. I have photo to show it, contact me at {Email Address Removed} I would like to confirm this fact or myth. —Preceding unsigned comment added by 116.14.191.235 (talk) 14:43, 15 May 2010 (UTC)

I removed your email address because Wikipedia often gets copied to many places around the internet, and leaving your email on it would potentially invite a massive amount of spam. We reply to posts on the desk where they were posted; we do not have the ability to send emails from Wikipedia. As for the lizard/snake, I know next to nothing about Cambodian reptiles. From my knowledge of the natural environment in other cases though, I am highly doubtful, though not ruling out, that such a relationship would exist. You can upload the picture to Wikimedia and post it here if you want. Falconus^{p t c} 15:40, 15 May 2010 (UTC)

Here's where you can upload a picture. If you have any problems with it, let us know. [9] Falconus^{p t c} 15:51, 15 May 2010 (UTC)

Also, now that I think about it, how is it possible for a liver to choke an animal? Maybe lizards are different, but I assumed that the liver was closer to the tail than to the head, and was an internal organ? Falconus^{p t c} 15:53, 15 May 2010 (UTC)

This seems spectacularly unlikely for dozens of reasons - but it's incredibly difficult to "prove a negative". If we found evidence that this story was true - it would be an open-and-shut case - we'd be done. But if we look and don't find evidence either way - then we don't really know whether the story is true or false...people don't often write about things that aren't true.

Why it's unlikely:

1. Why would a lizard evolve in such a way? Why is it advantageous to the lizard to have this grotesque lifestyle? If it's not advantageous, then the weird genetics that would cause this abmormal growth of it's liver would very rapidly be eliminated from the gene-pool. No other lizards have this problem - so it would require a very special genetic setup to make it happen - and that would de-evolve in very few generations - if it appeared at all.
2. Why would the snake stop at eating the liver? Once you've got the lizard pinned down and you've ripped into it's flesh enough to get to the liver - why not eat the entire liver (resulting in a dead lizard) or eat all of the other edible parts?
3. How does the lizard recover from the injuries required for the snake to get into the body cavity to reach the liver? Seems like it would die of it's injuries 99 times out of 100. The rate of infection would have to be really high.
4. As others have said...how on earth can the liver (which is at the back end of the animal reach the point where it can get around the throat?
5. Snakes don't have the right teeth and jaws for ripping and biting things - they swallow their food whole. How would it evolve the necessary teeth and jaws for doing this with such 'surgical' precision?

From all we know about biology and evolution and how living things 'work' - this seems insanely unlikely - but we can't prove it's not true. In my personal opinion, this is premium grade bullshit...but we're not going to be able to prove that.

SteveBaker (talk) 16:13, 15 May 2010 (UTC)

Snakes - unlikely. Worms make more sense. East of Borschov (talk) 21:29, 15 May 2010 (UTC)

Yes, yes -- pull the other one. See also Prometheus. Another fine myth. Vranak (talk) 22:48, 15 May 2010 (UTC)

Some American children depended on the family dog to eat their liver, secretly, under the dinner table. Edison (talk) 00:44, 16 May 2010 (UTC)

lyphoma

how is lymphoblastic lymphoma dfferent than lymphomblastic leukemia? —Preceding unsigned comment added by 64.223.232.173 (talk) 16:55, 15 May 2010 (UTC)

I'm not an expert in this field, but check out lymphoma and leukemia. Falconus^{p t c} 17:47, 15 May 2010 (UTC)

Lymphoma mostly effects the lymph nodes and thymus, leukemia blood and bone marrow. HalfShadow 18:58, 15 May 2010 (UTC)

Our article on lymphoblastic lymphoma is an onsourced stub. Here [10], [11] are two better articles. Both agree that T-cell-derived disease is more common than B-cell-derived disease. Quoting the second source, "clinical distinction between lymphoblastic lymphoma and acute lymphoblastic leukemia (ALL) has been arbitrary and has varied among different studies and institutions."

When it comes to chronic lymphoid leukemia, it is considered to be the same disease as small cell lymphocytic lymphoma. --NorwegianBlue ^talk 09:34, 16 May 2010 (UTC)

Well, yeah, I got my info from the first link you posted and it stated they were treated in basically the same manner, but they are technically separate diseases. HalfShadow 16:56, 16 May 2010 (UTC)

is it possible for people in different inertial frames to see events in a different order?

nt —Preceding unsigned comment added by 84.153.204.221 (talk) 18:53, 15 May 2010 (UTC)

Yes. See Relativity of simultaneity. --Mr.98 (talk) 19:49, 15 May 2010 (UTC)

I'm confused (I'm the OP). I didn't ask about being simultaneous or not, I asked about the order of events. For example, A observes that event 1 and then event 2, while B observes that event 2 and then event 1. ie if observer a and b thought post hoc ergo propter hoc, A would thik that event 1 caused event 2, while B would think that event 2 caused event 1. Is this possible? 82.113.106.107 (talk) —Preceding undated comment added 09:23, 16 May 2010 (UTC).

The article explains that this can happen only if the events are separated in space by a distance greater than that travelled by light in the interval between events, so "no" is the answer to your detailed question. Dbfirs 11:47, 16 May 2010 (UTC)

Ordering of events is dependent on agreements of simultaneity—that's what relativity of simultaneity is all about, and why it matters that they are in different inertial reference frames. That is, all measurements of "what time did something happen" are really simultaneity measurements, and so "when did this event happen, when did that event happen" are really simultaneity measurements (we both agree that our watches say the same time on them... unless we're in different inertial reference frames.) So under some circumstances, from the perspective of different inertial reference frames, different events will happen in a different order. I don't think causality can play into it, as Dbfirs has pointed out, because by definition the events need to be quite separately in spacetime. But maybe our pal Dauto can weigh in on this. --Mr.98 (talk) 14:06, 16 May 2010 (UTC)

Yes, all the explanations above are correct. Two events can be seen in different order by different observers, but only if they are so far apart that no information could have been transfered from one to the other (because it would take something traveling faster than light to do that). That way they cannot be interpreted as cause and effect by either observer. Dauto (talk)

Don't confuse an inertial frame (which you can think of as a huge network of clocks and metersticks, filling a large volume of space) with a person at a particular location recording the light that enters his/her eyes. Einstein carefully distinguished the two in his original 1905 paper on special relativity, using "observer" only for the person, but almost every later writer uses "observer" for the network of clocks and metersticks, even though that doesn't agree with the ordinary meaning of the word. Furthermore, the uses of "observer" in general relativity and in quantum mechanics don't agree with the way it's usually used in special relativity. It's probably better to never use the words "observer" or "observe" at all.

The clocks of an inertial frame are synchronized in a certain way (sometimes called Einstein synchronisation). Why that way? It's just convention. The universe doesn't enforce any particular synchronization of clocks. However, if you do choose to synchronize the clocks of two inertial frames in that way, and the inertial frames are moving relative to each other, then the times reported by one inertial frame's clocks will differ from the times reported by nearby clocks of the other inertial frame, in a certain predictable way. This is called the "relativity of simultaneity". The motion of the physicist in this thought experiment—what Einstein called the "observer"—is not relevant here. Any two physicists will see the same differences in the readings of the clocks, regardless of what they may personally be in orbit around. -- BenRG (talk) 19:28, 16 May 2010 (UTC)

Besian Idrizaj - how can a physically fit young footballer just die of a heart attack at age 22?

I am not that much older than him, but I drink and smoke and he's gotta have been more physically fit than I am.

Assuming he didn't take drugs or anything during that day, how could a 22-year-old, physically fit professional footballer just 'randomly' die of a heart attack just spontaneously. It seems strange. I'm not saying it isn't possible, but it's weird. How can he die, but Manuel Uribe remains alive? It boggles the mind.--Lightsin (talk) 21:16, 15 May 2010 (UTC)

It may be an undiagnosed congenital heart defect. This article details a number of other sudden deaths of young athletes which were attributed to such conditions. -- Finlay McWalter • Talk 21:20, 15 May 2010 (UTC)

Also take a look at Sudden cardiac death for more possible explanations. Sometimes these things just happen to people you wouldn't expect it to happen to. --Kurt Shaped Box (talk) 21:26, 15 May 2010 (UTC)

See also Alexei Cherepanov. One common link is that there were both born and raised in comparatively impoverished parts of the world (Russia, Albania). These are both solidly Second World nations that were under the yoke of Communism until, well, at least the fall of the Berlin Wall on November 9th, 1989. Vranak (talk) 22:41, 15 May 2010 (UTC)

You mean under the yoke of Communism for the first 2 years and few months of their respective lives? Nil Einne (talk) 23:23, 15 May 2010 (UTC)

Yes. A lake may dry up but the water still goes somewhere. Vranak (talk) 23:34, 15 May 2010 (UTC)

So you're saying they moved to China so they could be under the 'yoke of communism' and that's why they had heart attacks? As an interesting aside, they were both at least 1.85m as well... Nil Einne (talk) 11:42, 16 May 2010 (UTC)

My friend's son died of sudden, inexplicable cardiac arrest in his early 20s, even though he was a very healthy athlete. Because my friend is a famous geophysicist, with a very analytic mind trained to glean information out of noise, he has published a website with a lot of analysis about the predictability/unpredictability of his son's condition, (as well as some tributes to his son). You can read about the extremely unlikely statistics of sudden cardiac arrest in healthy athletes here: Causes of sudden death in young athletes. Nimur (talk) 00:21, 16 May 2010 (UTC)

There isn't necessarily an explanation beyond bad luck. While the chance of something like this happening to a person who is otherwise in good health and with no obvious explanation may be a million to one (Nimur's link says 200,000 to one per year), there are far more than a million people in the world so we would expect it to happen fairly often. --Tango (talk) 00:34, 16 May 2010 (UTC)

It may happen more frequently with athletes, who put stresses on their heart the average person doesn't, so while someone may live to old age with such a heart condition going undetected, an athlete may cause their own premature death. Some American athletes that spring to mind are Hank Gathers and Reggie Lewis. There's a number of others listed at List of sportspeople who died during their career. One non-athlete that springs to mind who died this way was John Ritter, though he was middle aged (by no means old). --Jayron32 00:57, 16 May 2010 (UTC)

Had a friend in college who played football in high school, he was as fit as a fiddle at the time, and he'd had a heart attack. He's fine now, don't recall what the issue was. – Kerαunoςcopia^◁_galaxies 05:18, 16 May 2010 (UTC)

I knew a 30 year old who had a severe heart attack, he survived by dint of quick medical response, it was caused by a genetic defect in a coronary artery. 86.4.186.107 (talk) 07:40, 16 May 2010 (UTC)

Hiccups

Question removed per Wikipedia policy. We cannot provide advice concerning medical or legal issues. The only advice I can give on the Wikipedia reference desk related to medical advice requests is to see a doctor. Sorry about that. Falconus^{p t c} 22:38, 15 May 2010 (UTC)

This is an encyclopedia, so you can look at the article Hiccup for general information on Hiccups. Buddy431 (talk) 01:07, 16 May 2010 (UTC)

May 16

London Blitz

How many apartment buildings can one V-2 rocket destroy? (Assume that these are your typical pre-World War 2 apartment buildings, five stories or so and unreinforced brick/masonry construction.) 67.170.215.166 (talk) 00:06, 16 May 2010 (UTC)

The best information I can find (after a very quick search) is in our article where it says: "A scientific reconstruction carried out in 2010 demonstrated that the V2 creates a crater 20m wide and 8m deep, throwing up around 3000 tons of material into the air." 20m isn't that much, so you are probably talking about 1-3 buildings destroyed with a few surrounding buildings damaged. V-2's weren't very accurate, though, and many of them didn't hit London at all. It is also worth nothing that there weren't many apartment buildings in London during WW2, they were mostly build after the war. During WW2, high density housing would have been almost all in the form of terraced houses. --Tango (talk) 00:23, 16 May 2010 (UTC)

Although the crater was 20m wide, the actual damage (you'll have had the explosion travelling through the air too) seems to be a little bigger from the third picture (of Finland Rd and Revelon Rd) on this site. There's a considerable chunk missing from the street about a dozen houses wide, although the site doesn't mention whether any extra were cleared for the new buildings. Our article on the V-2 says that although initially quite inaccurate, a radio guidance beam was eventually used that could plant the rocket within metres of its original target. One of the reasons that V-2s, on average, only killed a couple of people is the success of the Double Cross system, which used captured Nazi spies to feed back wonky information that gradually walked the V-2 hits away from central London and towards less densely-populated areas. Really quite ingenious. Brammers (talk) 08:20, 16 May 2010 (UTC)

Channel 4 in the UK recently had a program about this, Blitz Street. The last episode covered V2 bombs. It's available on 4od to UK and RoI residents here. CS Miller (talk) 15:27, 16 May 2010 (UTC)

Neutralization of Ingested Acids

I just ingested a salad with a generous amount of rice win vinegar (I like sour things) and some barbecue with a vinegar-based sauce. This occurs to me to be a large amount of acid ingested, so I was wondering how does the body rid itself of excess ingested acid?24.88.87.41 (talk) 02:19, 16 May 2010 (UTC)

See Acid-base homeostasis. One major source of buffering is the bicarbonate in the blood, which can react with protons to generate carbon dioxide (which you exhale) and water. Another way that the body excretes excess acid is in the form of renal tubular reabsorption of bicarbonate resulting in net acid excretion in the urine. That being said, I doubt that ingestion of normal amounts of vinegar in foods would cause any significant acidosis. --- Medical geneticist (talk) 02:41, 16 May 2010 (UTC)

Followup question about the premise: I had thought, with my very vague knowledge of the digestive tract, that the ingestion of any amount of, say, vinegar, would not add "net" acid to the body, because human stomach acid is so strong; whatever mechanism exists to neutralize the stomach acid that goes into the duodenum must be so powerful that weak acids like vinegar would be neutralized instantly, with the mechanism laughing at the puny vinegar. Comet Tuttle (talk) 06:51, 16 May 2010 (UTC)

The hydrochloric acid in the stomach is recycled. Acetic acid isn't. It's not really harmless to the body, just at low doses the body handles it, at higher doses it's actually dangerous. And see [12]. The hydrochloric acid in the body is recycled mainly in order to keep the acid/base balance correct. Adding extra acid does in fact disrupt that (as does vomiting, see: Metabolic alkalosis). Presumably the body can deal with an imbalance to a point, but beyond that it can cause serious damage. See also Metabolic acidosis and Acid-base imbalance. Ariel. (talk) 07:30, 16 May 2010 (UTC)

Loons in Colorado?

I didn't think there were loons in Colorado. I'm currently tucked away in the Rockies, it's nightfall, and I'm hearing a bizarre "laughing" call, though the direction is impossible to tell (the sound echos around the valley I'm thinking). There is a large lake a bit off in the distance, however. The sound is similar to the laughing parts near the end (or second half) of the sound clip on the Loon#Etymology_and_taxonomy page. Before I check some reference books (Google wasn't being too helpful, though evidently there have been loons photographed around the state, I'm just not sure why they'd be here so soon), could there be some other animal that "laughs" like this? I have not heard any bugling (if there were, I'd think it was elk, anyway) or other sounds that were played in that clip. Any help would be great, thank you. – Kerαunoςcopia^◁_galaxies 03:10, 16 May 2010 (UTC)

Coyote? Rckrone (talk) 05:01, 16 May 2010 (UTC)

Interesting, didn't even occur to me. The coyotes can usually be heard howling right around dusk, but I'd never heard them "laughing" like this before. However, I thought I also heard "youngins", if that makes sense. So maybe they were just coyotes. I hope they do it again tomorrow. – Kerαunoςcopia^◁_galaxies 05:12, 16 May 2010 (UTC)

It isn't unusual to see loons in the Colorado area. I have been exploring the database of sight records at eBird.org and have found a map of reported sightings along with frequency counts. A link to that page is here: http://ebird.org/ebird/comonloonmap. eBird.org is a wonderful website for both tracking your personal birding escapades, and for examining birding data from around the Americas. A link to Common Loon sightings specifically in Colorado is provided here:http://ebird.org/ebird/commonloonmap/usa/colorado. A link to the average count of Common Loons throughout the year in Colorado is here: http://ebird.org/ebird/commonloon/usa/colorado/averagecount. I hope this helps clear up any questions, and keep on birding! Stripey the crab (talk) 14:55, 16 May 2010 (UTC)Stripey the crab

Hurricanes crossing the equator

In recorded history, has there ever been a hurricane that has crossed the equator? --The High Fin Sperm Whale 04:56, 16 May 2010 (UTC)

According to the list of tropical cyclones, this has never happened. Cyclone Agni in the Indian Ocean in 2004 came close to the equator but did not cross it. However, in the article about the storm it appears to say that the center did cross, or may have crossed, the equator while the storm was still forming (the wording is a bit confusing). --Anonymous, 05:17 UTC, May 16, 2010. —Preceding unsigned comment added by 208.76.104.133 (talk) 05:18, 16 May 2010

I asked a question that was similar to this awhile back. The responses may be helpful: Link to August 22, 2009 Archive: Tropical_Cyclone_Crossing_The_Equator Falconus^{p t c} 19:57, 16 May 2010 (UTC)

medical malpractice

I've heard that the greatest abusers of drugs are not street addicts but doctors and nurses. Can anyone confirm or refute this? 71.100.0.29 (talk) 06:12, 16 May 2010 (UTC)

You're the one making the claim. Generally, it is the responsibility of the person making the positive assertion to provide evidence to back it up. Generally "I've heard" is a very unreliable source. We must assume that claims like this are false unless anyone can provide evidence to the contrary. --Jayron32 06:15, 16 May 2010 (UTC)

This article claims the rate of substance abuse among "pharmacists and some health care professionals" is higher than among the general populace, though this article mentions the anesthesiologist substance abuse rate is only around 2%. Googling "drug abuse by doctors", there seem to be numerous statements that it's hard to gauge the true rates because it's all hidden and confidential. Comet Tuttle (talk) 06:42, 16 May 2010 (UTC)

It seems unlikely but there are several problems in providing a statistical answer. First, how do you define a "street addict"? Someone who buys any illegal drug from a street seller? Someone who lives on the street because his illegal drug addiction has cost him his home? Someone who lives on the street because alcohol addiction cost him his home? Second, how do you define "substance abuse"? Do legal substances like tobacco and alcohol count? Any use at all, or just use to the point of impairment? Alcohol is certainly the most common substance abuse that leads to impairment among doctors and nurses. Third, it is possible to estimate substance abuse that leads to loss of medical or nursing license because that is published by the state boards of medicine or nursing. I can tell you that every quarter maybe a couple of doctors in a populous state lose their licences for drug related behavior, but most of those license losses are because the doctor broke the law (i.e., selling oxycontin to addicts) rather than because they were addicted. There are not public statistics on those doctors or nurses who quietly and voluntarily go to rehab. And obviously there are no public statistics on how many doctors and nurses are abusing substances but continue to function. So your question is simply not answerable as phrased. Finally, you do realize that substance abuse by professionals is not the same thing as "medical malpractice" and is only tangentially related? Substance abuse per se is not malpractice. alteripse (talk) 14:27, 16 May 2010 (UTC)

Another controversial, unsourced post about drugs. This trolling needs to stop. Regards, --—Cyclonenim | Chat  14:45, 16 May 2010 (UTC)

'Banana' Snake

Good afternoon

I have been given some information regarding a snake that bites into the heads of bananas, the venom deposited, then a creature/person eats the fruit, succumbs to the venom and falls, thus creating the meal for this meat-eating snake.

Can anyone please verify this information?

Many thanks 88.108.223.239 (talk) 11:15, 16 May 2010 (UTC)

It sounds almost as unlikely as the liver-eating snake above, but I'm prepared to be amazed if anyone can come up with even a scrap of evidence. Dbfirs 11:25, 16 May 2010 (UTC)

(edit conflict)It seems unlikely, googling "banana snake poison" doesn't bring anything up. I found this which discusses using bananas poisoned by snakes and then being used as a poison. Why would a snake go to the bother of waiting for something to eat the particular banana it had bitten when it could just bite the animal instead? Where did you hear it from? 131.111.30.21 (talk) 11:28, 16 May 2010 (UTC)

As counter-evidence, this website: Department of Forensic Medicine, Maulana Azad Medical College, New Delhi, Indiasays: "The question is often asked, what would happen if one ingested the snake venom? Would he die? The answer is "no". Snake venom is a mixture of proteins which would be digested in the stomach. It is also suggested that snake venom is not absorbed from the gastric mucus membrane. However if a person is suffering from gastric ulcer, some snake venom may be absorbed through this ulcer and may pose danger to the person ingesting snake venom." Dbfirs 11:33, 16 May 2010 (UTC)

Sorry, I didn't realise that this is the same link as that provided by 131.111.30.21 Dbfirs 11:41, 16 May 2010 (UTC)

Also note that venom is not the same as poison.--Shantavira|^{feed me} 14:54, 16 May 2010 (UTC)

Lunatic nonsense, per sé. Edison (talk) 22:09, 16 May 2010 (UTC)

Banana Snake extra answer!!!

Hello again

Im sorry, being a newbie here, I am unaware how to make this part of the answer section of my original question.

Many thanks for the answers given so far.

I agree about why would the snake bite into the banana, and not go direct (cut out the middle man eh?)... it did cross my mind, but of course, there is no telling what instincts are driving the particular action, especially in a 'caught in a trap situation'.

In answer to the querie, I got it from my hubby who was told the info by a colleague who works for a banana processing plant in UK. (Fyfe's depot in Tilbury perhaps?) Anyway, he was telling hubby about the gas lined packing sacks, the 'antidote' spray to the gas and the fact that when the plants are removed from the sacks at some point during the process, scorpions can be seen scuttling around, as well as the snakes occassional appearances. These creatures are then 'dealt with' (official term???). Anyway, I was amazed by all this and wanted to verify the info re the snakes as of course if it's true, then everyone should be made aware.

Thank you re the info about the efficacy of the poison/venom and stomach...

I will keep hunting, and if I find any more, I will post back here to let any interested party know. Many thanks again, I much appreciate your help. 88.108.223.239 (talk) 16:04, 16 May 2010 (UTC) —Preceding unsigned comment added by 88.108.223.239 (talk) 16:02, 16 May 2010 (UTC)

It strikes me that there might be some confusion here. There are certainly poisonous/unpleasant animals that live in banana trees and potentially pose a threat to people who work with bananas (e.g. the Brazilian wandering spider). I don't think any of these pose a threat because they sting bananas and make them poisonous—this seems totally unlikely. But for someone who works with bananas, these kinds of things are probably not uncommon threats to watch out for, and there are probably means of controlling them built into the system. Rest assured, if consumers were at some kind of risk I'm sure people would have been aware of it by now (do you know anybody who has keeled over from eating a banana? Have you ever heard of such a thing? If not, then it's probably not a major risk). --Mr.98 (talk) 18:44, 16 May 2010 (UTC)

Onion Bully

Anyone have any credible suggestions about how Onion Bully works? It is a metal shoehorn that goes in the user's mouth while they cut onions that supposedly stops them from crying. Other than "tear science" and "the shoehorn tells your brain to turn off your tear ducts" can the wonderful persons of the science ref desk provide some clue as to how this (probably useless) invention might work? --Jabberwalkee (talk) 16:24, 16 May 2010 (UTC)

Most likely Placebo effect. ---- — Preceding unsigned comment added by 76.228.199.229 (talk)

I can't find any reference to it that isn't a recycling of the YouTube video or a reposting of a single Geekologie blog post. Based on the name and logo color scheme, I can't help but wonder if it's an elaborate hoax by The Onion. TenOfAllTrades(talk) 18:30, 16 May 2010 (UTC)

I think it is to do with the fact that it encourages you to breath through your mouth. I find it helps when cutting onions and there seems to be a fair amount of anecdotal advice on the web also suggesting this (e.g.. So basically there is no need to but the product, just breath through your mouth. 86.7.19.159 (talk) 18:46, 16 May 2010 (UTC)

I would just suck on a Jolly Rancher while cutting an onion, I wouldn't spend $10...wait, I get two for that price?! :D – Kerαunoςcopia^◁_galaxies 21:31, 16 May 2010 (UTC)

One traditional way to avoid onion-related lacrimosity is to suck on a metal spoon. I suppose the Onion Bully works in the same way, and is intended for those without spoons in their kitchens. DuncanHill (talk) 21:34, 16 May 2010 (UTC)

The mechanism they describe, turning off the tear ducts, sounds like a bad idea! If my eyes are irritated by an onion, I personally would want the irritation washed away. Paul (Stansifer) 22:23, 16 May 2010 (UTC)

The slot in the device keeps an airway open between the lips so that inhaling is through the mouth instead of the nose. Cuddlyable3 (talk) 22:54, 16 May 2010 (UTC)

Exposure to Pornography

I'd like to preface this question by stating the obvious that children themselves should NEVER be sexualized. My question is regarding the dangers of exposure...There seems to be a perpetual debate regarding children witnessing sexual acts on tv and pornography on the internet. People spend lots of time filtering what their children see but besides a sense of shame about nudity is there really any evidence children will be psychological harmed from seeing sexual material? I wouldn't want my son or daughter to see internet porn but I'm wondering why I think that besides cultural norms. Surely back in prehistoric times people had sex out in public all the time so what changed and why do we now consider early exposure to be so harmful? TheFutureAwaits (talk) 20:21, 16 May 2010 (UTC)

Interesting question. You could take the prehistoric point even further and suggest that anyone who passed through puberty might have ended up reproducing, even in young teenage years. That would suggest to me that there's little chance of exposure to pornography at that age being harmful. Pre-teenage years is a different question altogether. Regards, --—Cyclonenim | Chat  21:04, 16 May 2010 (UTC)

Seriously beg to differ. We have no evidence either way of prehistoric attitudes; we do have evidence of social discomfort with parental nudity back 3000 years or more in our own culture (Genesis), and there is plenty of reason to think that the core stories and cultural values in it go back a lot farther. On the other hand, there is testimony from explorers and others that public sexuality in various non-Western cultures was not always hidden or an object of modesty or shame. However, both of those things are different from pornography, and speculation about prehistory is not very relevant to the question of how harmful exposure to modern pornography may be to modern children. I doubt one can separate out the social context: I would contend that certain items might be "porn" in one culture but not another, and that the effect of large exposure to children in the two cultures would be partly a function of whether it is considered "porn", with all the associated shame, guilt, taboo, etc that goes with it for children. There is evidence that exposure to substantial amounts of televised violence and sex changes attitudes of children, including both responses to them and lowered thresholds of engaging in it. Few people think that single exposures are especially harmful, and I doubt if anyone has tried to measure dose response. The other difficulty with answering this is that the kind of parents who allow children to view large amounts of porn are likely to be unusual in many ways, making it difficult to disentangle specific parenting actions. I am sure that if you google exposure of children to pornography you would get a fuller answer. alteripse (talk) 21:40, 16 May 2010 (UTC)

This might sound like a troll post but really, it's not, I'm at work so I can't exactly google for sources! Anyway, only a few months ago, some group in Canada tried to do a study into the effects of exposure to pr0n on the social life of college students, but they couldn't find enough students who didn't watch pr0n. It was reported in Nature magazine. Vespine (talk) 22:15, 16 May 2010 (UTC)

I must say it's not surprising. I assumed the original questioner was referring to pre-adolescent children, not young adults. It would be impossible to do even an ascertainment study in children. alteripse (talk) 23:16, 16 May 2010 (UTC)

I agree with alteripse that sexuality and pornography are different things, and mixing up cultural norms within a given culture always seems to be a recipe for social/individual problems. That said I do think that the bruhaha about protecting the children, especially in modern US politics, is often overblown. Original Research ahoy: When I was, I don't know, 9 or 10 or so, my friends (all male) and I were insatiably fascinated by the idea of nudity and sex (though we were definitely prepubescent—we, or at least I, were certainly not interested in having sex at this point), and sought out all sorts of pornography in our parents' closets, bathrooms, and other places they thought we were too innocent to root through. Reading Playboy was pretty exciting for us, in part because it was clearly taboo. I don't think it traumatized me, though perhaps this was because it was on my own terms, and I don't think it irreversibly screwed up my future love life, attitudes towards women, and so on (but really, who knows?). Now, I don't claim to know if it's the same thing for all children, or how much of that is due to my being white, American, and middle class, or how much it would be different if what we were exposed to wasn't the relatively mild Playboy spreads compared to, say, what passes for "hardcore pornography" on the internet these days. But I don't think it's a total given that even in this modern culture that all children are "innocents" until they magically become 18, or that anything sexualized before that will "scar" them in some horrible way. (I agree that you need to set an age of consent, for clear administrative purposes.) I think adults in the modern US (and probably elsewhere) have a peculiar way of forgetting what they were like as children in imagining how they would like their own children to act. --Mr.98 (talk) 02:21, 17 May 2010 (UTC)

May 17

NG photo question

(Moved from misc desk)

OK, so this one[13] has puzzled me ever since I saw it in the magazine about 3 years ago. The bug on the right is a trap-jaw ant. The critter on the left is unidentified, and the caption is a bit vague. So my question is for all you insect experts out there: What's the bug on the left, and has the ant just bitten its head off, or what? ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:47, 16 May 2010 (UTC)

This is a biology question. With no research I'd say the insect on the left is some sort of grasshopper, compare the picture that heads the WP article, not exact but . . .. The grasshopper's head has not been bitten off as you can clearly see its large multifaceted eyes and jaws. Richard Avery (talk) 07:34, 16 May 2010 (UTC)

Yes, looks very much like a grasshopper nymph, with its head pretty much intact. The only thing missing may be the tips of the antennae, not sure. --Dr Dima (talk) 01:42, 17 May 2010 (UTC)

Tomato and Corn

Why is a tomato a fruit? And is corn a vegetable or grain? wiooiw ^(talk) 01:55, 17 May 2010 (UTC)

See Tomato#Fruit or vegetable?. Dismas|^(talk) 02:04, 17 May 2010 (UTC)

(edit conflict) The term "vegetable" has no definition in horticulture; it is applied somewhat arbitrarily. Fruits, by definition, are the mature, seed-bearing ovaries of angiosperms (flowering plants). Grains (cereals) are those grasses of the family Poaceae. Here, I am assuming that by corn you are referring to maize; be careful with your use of the word, since "corn" can be used to refer to the principal cereal crop of a region. Intelligentsium 02:07, 17 May 2010 (UTC)

Yes, referring to maize, thankyou. wiooiw ^(talk) 02:41, 17 May 2010 (UTC)

Caesar's last breath

I read in a Paul Zindel novel that every person in the world contains at least two atoms of Julius Caesar's last breath, or something along those lines. I find it hard to believe (and obviously impossible to prove), but do the nature of atoms allow for something like that to happen? Thanks!  ?EVAUNIT^{神になった人間} 02:44, 17 May 2010 (UTC)