Wikipedia:Reference desk/Archives/Science/2010 May 13

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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)