Wikipedia:Reference desk/Archives/Science/2006 October 17
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October 17
editVariables
editI don't understand constants, the control, independent and dependent varibles. Or what role do they play in a science fair project? Please explain. Thank You. Molly Smith
- Hi Molly. The dependent variable is the variable that the experimenter cannot control, the indepedent one is the one you can control. So if my experiment is meant to answer a question like, "what color of paper attracts more bees to it?", I can change the color of the paper directly, but I can't change the bees directly. Thus my experiment would consist of me changing the independent variable (the paper) in order to observe the change in the dependent variable (the bees).
- Constants in this context probably refer to the fact that there are some variables you don't want to change. For example, in my paper/bee experiment, I would want to make sure I was doing all of these experiments at around the same time of the day. Otherwise any effect I saw could potentially be due mostly to the changing time of the day it was — perhaps bees are more active at one time of the day than another, and so I wouldn't really be measuring the dependent variable purely if some complicated factor like that was also at play.
- Controls are not always possible — it depends on the type of experiment it is. In my color/bee experiment there could be no control. Controls are only possible in experiments where you have a very definite causal hypothesis; for example, if I were a doctor and I wanted to a study of a new medicine, I would want to make sure there were some patients I was monitoring who were not taking the medicine, or were taking a placebo (which looks like medicine but has no biological effect). That way I would be able to tell the difference between the medicine I was testing and no medicine at all; the people who were not taking medicine would be the "control" to my study. Again, not all experiments can have, or really need, a control — it depends on the type of question being asked.
- You might find the Scientific method article at Simple a good resource; it is much more readable and less pedantic than the scientific method article on Wikipedia. Hope that is helpful. --Fastfission 01:42, 17 October 2006 (UTC)
- This is just to clarify an already INCREDIBLE explanation.
- The constants are the things kept the same across all of the experiments. The only things that you should change from one experiment to the next are the Independent Variables. Example: If you were comparing the length of time it takes to bake cakes using different types of flower, you would want to make sure that the other ingredients used were of the same brand for all of the experiments. You would also want to make sure the amounts were the same, you used the same type and brand of cake pan, and they should all be cooked in the same oven at the same temperature. The purpose of keeping these things constant is so the effect of the Independent Variable can be isolated.
- The control is the group in your experiment that has no Independent Variables. It is what all of the experimental groups are compared to. My cake experiment would also lack a control. If you were comparing the effect of different types of soda on tooth decay, the control would be a tooth kept out of soda. The purpose of a control group is so that you can show that the Independent Variable was (not) causing the change. The control group shows what would have happened naturally, without any outside interference.
- The Independent Variable is what you change in the experiment. In my cake example, the Independent Variables would be the different types of flour, and in my soda example the IV would have been the type/brand of soda. The independent variables are what make an experiment an experiment. The IV should be the only thing to change from group to group.
- The Dependant Variable is the reaction to the IV. In my cake example the DV would be the amount of time it took to bake the cake, and in my soda example the DV would be the rate of tooth decay. This is what you are doing the experiment to find. If you are comparing the results of multiple experiments, you would compare there dependant variables; depending on the type of experiment you may compare the IVs as well, but you will always compare the DVs. If you are doing just one experiment, such as how long does it take to bake a cake with X brand flour, or how long does it take to dissolve a tooth using Coca-Cola, this would be your answer.
I hope that we have been able to help you, and good luck in the science fair. THL 05:02, 17 October 2006 (UTC)
Combustion of BIO Gas.....
editI'm working on an anaerobic digester design and i found that the CH4:CO2 ratio is between 1:1 and 3:2. In addition it may contain Hydrogen Sulphide, Nitrogen, Amonia and Hydrogen in small amounts.
I'm planning to utilize this gas to produce CO2 to be used in another industry. So i would like to know further information about following issues.
1. will it be effective to combust methane+CO2+other trace gasses mixture to produce CO2
(will the excess CO2 affect the complete combustion?)
2. What will be the products after combustion of the above gas mixture?
3. what will happen to NH3 and H2S after combustion?
It is planned to combust the mixture in lower temperature (Less than 200 C)
Appreciate any suggestion to success my effort and any links regarding this process will be really helpful to me...!! Thank you.
--192.248.8.100 04:27, 17 October 2006 (UTC)Sithara from Sri Lanka
- How much of the energy used by the body is actually consumed by the brain? Hoping for an answer in kcal/day or something like that. A similar question is: how much of the body's oxygen does the brain use? (I think the answer to this is around 25%, but I can't find any sources that give a figure, let alone one that supports mine)
- Someone told me recently that the brain cannot burn fat or protein to supply itself with energy. I think this is probably not true, but I can't find a source either way. Does anyone know?
Thanks in advance for any answers!
N Shar 04:47, 17 October 2006 (UTC)
- the brain uses ~1760 kJ/day, pretty much entirely from glucose. the brain will burn glucose as its fuel of choice, if little glucose is availible from the diet, gluconeogenesis in the liver is used to synthesise the required glucose from other materials. in prolonged starvation the brain can use other fuel sources such as ketone bodies, but not very well. further info[1]. Xcomradex 05:28, 17 October 2006 (UTC)
- Yay! Thank you! N Shar 05:30, 17 October 2006 (UTC)
- That's 20 W, in case someone wanted to know. —Bromskloss 11:31, 17 October 2006 (UTC)
- and apparently the brain uses ~20% of the oxygen for your body, but that is from a snake oil pusher[2]. Xcomradex 05:38, 17 October 2006 (UTC)
I would expect the ratio would vary dramatically, based on whether you are sedentary but engage in intellectually challenging pursuits, or meditate while exercising strenuously. StuRat 14:53, 17 October 2006 (UTC)
- Right. The fact that the brain needs more energy when thinking is a most valuable thing for researchers studying the brain with positron emission tomography: The patient get radioactively marked glucose, and the PET scanner then shows where this glucose is used. And, BTW, as nobody has commented on it so far: If I am not mistaken the percentage of energy and the precentage of oxygen that the brain uses as compared to the total organism should be the same. After all, a cell always needs the same amount of oxygen in order to use a given amount of energy stored in food. But I'm not sure. The answer should be hidden somewhere in the citric acid cycle. Simon A. 16:05, 17 October 2006 (UTC)
- As for the second question: It is true. The brain can't burn fat or protein. It gets all its nourishment from the glucose in your bloodstream. This is one of the main reasons you have a liver - to store glycogen and maintain your blood-sugar level. It's also why it gets tough to think straight when your blood sugar is low. Once your liver glycogen is depleted, the brain starts consuming ketone bodies (acetone and similar) from your blood, which your body produces from catabolizing the proteins of its own tissue. This is why your breath starts to smell of acetone when you start starving or if you run for about 30 km or so - prolonged exersize follows the same process as starvation, but at a faster rate. The body needs to produce these ketone bodies because nerve tissue doesn't have the ability to break down protein itself. The amount of energy used by the brain or any other organ isn't constant of course, in particular once you start starving. Then the body starts shutting parts down to conserve energy. --BluePlatypus 23:02, 17 October 2006 (UTC)
Snake Bite
editWhat's the worst snake to be bitten by ?
- The Fierce Snake is the worst land snake, but there is at least one sea snake which is more venomous. Not many people get bitten though. --liquidGhoul 05:11, 17 October 2006 (UTC)
- What about the overall death experience? A slow painfull death would be much worse than a quick death from a deadlier snake. Gaboon vipers have two inch fangs and actually eat small antalope!
- Then I would say getting eaten by a python would be the worst. It's a matter of opinion. --liquidGhoul 05:37, 17 October 2006 (UTC)
- Is there some sort of pain index pertaining to snakes, as there is for insects with the Schmidt Sting Pain Index? freshofftheufoΓΛĿЌ 06:08, 17 October 2006 (UTC)
- That involved Schmidt subjecting himself to insect stings. Noone is stupid enough to do that for snakes. --liquidGhoul 06:18, 17 October 2006 (UTC)
- I don't see how it couldn't be done from case studies, at least as an "approximation". freshofftheufoΓΛĿЌ 05:34, 19 October 2006 (UTC)
I have heard that many deaths due to snake bites are mainly due to fear and panic rather than the poison itself !. -- Wikicheng 06:54, 17 October 2006 (UTC)
- You don't die from fear, maybe panic if you run off a cliff or something, but no. Most deaths from snake bite are from the venom. A large proportion of snake bites are after they have been picked up by someone. It is amazing how stupid some people can be. --liquidGhoul 07:36, 17 October 2006 (UTC)
- Well, snake oil is just so tasty. — X [Mac Davis] (SUPERDESK|Help me improve)08:38, 17 October 2006 (UTC)
- I'd never even heard of that term before, and now it is used in two threads in a row! --liquidGhoul 11:17, 17 October 2006 (UTC)
Reversing a Black Hole...
editThis question might be a bit long-winded, but, here goes. Hyperthetically, imagine a very young, 'borderline' Black Hole: A supernova 'just' went-off and produced said black hole. By 'borderline', I mean that had the original "sun" been JUST A BIT less massive, it would have produced a neutron star instead. Now, would it be possible to FORCE-FEED this black hole with enough matter to change it into a neutron star? For that to happen, would the matter have to be "fed" at faster than the speed of light? (of cousre impossible, hence, hyperthetical). Once a black hole, ALWAYS a black hole? (ignoring evaporation). Just something to 'chew' on. Thanks, Dave152.163.100.74 06:55, 17 October 2006 (UTC)
- Addendum...What I really meant to ask was, is a SINGULARITY reversible? 152.163.100.74 07:12, 17 October 2006 (UTC)
- No one really knows except Stephen Hawking. And he's not telling 8-)--Light current 07:27, 17 October 2006 (UTC)
- You have it confused—black holes have greater mass than neutron stars. You could feed a neutron star and squeeze it until it became a black hole. — X [Mac Davis] (SUPERDESK|Help me improve)08:42, 17 October 2006 (UTC)
- However, a small singularity can "evaporate" due to Hawking radiation. StuRat 14:42, 17 October 2006 (UTC)
No I don`t Mac Davis. Perhaps I should have posed my question thusly: Can a black hole, or even a neutron star, for that matter, be 'force-fed' to return to main-sequence 'status'? Touche about Stephen, Light! 8)Dave 152.163.100.74 14:29, 17 October 2006 (UTC)
- Well, there's this: if a black hole is rotating fast enough, and you skim objects across it at just the right trajectories, you can extract as much as ~29% of its mass/energy through the Penrose process before its rotation slows to zero. But this process doesn't decrease the area of the event horizon, so it can't destroy the singularity. Melchoir 15:11, 17 October 2006 (UTC)
- So yes, once a black hole, always a black hole (ignoring Hawking radiation). Removing mass is not possible even if you can travel faster than light. --Bowlhover 00:28, 18 October 2006 (UTC)
Amount of Water in the World
editIs there a set amount of water in the world? I understand the process of condensation and all that but I wonder, if it's always a circular movement, then is there a certain amount of water thats continually moving around or is water created and destroyed in some way, if so, how?
Thank You
- Should stay about the same, until the next comet strike that is. 152.163.100.74 07:06, 17 October 2006 (UTC)
- Water is not created or destroyed. It falls as rain, drains into rivers and seas, is evaporated into the atmosphere and falls as rain again. Quite clever really! It should be called the water cycle. Dont know if it is. 8-)--Light current 07:25, 17 October 2006 (UTC)
- Not strictly true, you forgot chemical rxns. eg in hydrogen cars 2H2 + O2 => 2H2O ; or burning of carbohydrates and hydrocarbons nCH2O + O2 => CO2 + H2O , to pick 2 important cases. (H2O is a greenhouse gas) Water is destroyed (split) by plants in photosynthesis, added to CO2, to make those carbohydrates. Next question is whether number of C H and O atoms is constant on Earth. Care to guess? ==GangofOne 07:48, 17 October 2006 (UTC)
- I think what you are talking about is more strictly to do with the carbon cycle. Im ignoring H2 cars etc.--Light current 08:09, 17 October 2006 (UTC)
- There's a fair bit of water in space, eg in comets and other flying chunks of ice. There is even a theory that all the water on Earth came from those colliding with Earth. Of course there is much less of them left now, but they will still add to the amount of water on Earth, possibly negligible, but still. Conversely, won't some water evaporate into space? I remember wondering about that when I was a kid, and I never got an answer. DirkvdM 10:51, 17 October 2006 (UTC)
- Water vapor, at a relatively hefty 18 amu, has a horrid time escaping Earth's gravity. Using the Maxwell distribution, a conservative value for Earth's escape velocity in the upper atmosphere, and the Integrator (as a high-precision error function evaluator), I get that at 300 K, about of water molecules (as in, one in every ) will have escape speed at any given time. (Of course, many of those will be moving downward! But this is just a factor of 2 or 3.) Supposing the entire mass of the Earth to be water vapor making these attempts (that's molecules), that they each get to try once per mean collision time (which I approximate as their mean free path divided by the expected particle velocty ), and that all attempts with the appropriate speed are magically directed "out" and encounter no collisions during the escape, I get an attempt frequency of . Of course, there's still an expected success interval of because of the ludricously low probability of escaping per try. (At a not-unreasonable upper-atmosphere temperature of 1000 K, the much better odds of having the escape energy ( ) and somewhat shorter mean collision time predict 480 trillion escapes per second; however, this is still only 14 nanograms of water per second, and that's still with the whole Earth of water vapor with magic escaping skills.) In short, no. The water isn't going anywhere. --Tardis 05:51, 18 October 2006 (UTC)
A huge amount of water gets entrained in subduction zones. There is actually a geologic water (and carbon) cycle, which can be tracked in geologic time. The amount of water in the biosphere varies over millions of years. --Zeizmic 11:58, 17 October 2006 (UTC)
So, to answer the question, yes, there is more or less a constant amount of water on Earth. While it can be created or broken back down to hydrogen and oxygen, these processes are more or less in equilibrium, so there is no net increase or decrease over time. StuRat 14:21, 17 October 2006 (UTC)
- To DirkdvM...No, I don`t think so. Most of the humidity, water, is contained in the troposphere, and to a much lesser extent, in the stratosphere. That`s where all the 'weather' is. THAT part of the atmosphere which would/could evaporate would be 'dry'. Hope this answers your long-ago childhood question! : ) Dave 152.163.100.74 15:49, 17 October 2006 (UTC)
- To add...if you meant wouldn`t some water escape/evaporate into space during/following a cometary COLLISION, then, I`d have to say, "Of course!". But, I think there would have to be an over-all GAIN, assuming the comet would have brought megatons of water with it! Dave 152.163.100.74 16:09, 17 October 2006 (UTC)
- To StuRat: "these processes are more or less in equilibrium,"; That's only your unsupported assumption. Surely burning down half of the Amazon basin is a noticable change. --GangofOne 21:11, 17 October 2006 (UTC)
- Not relative to the total amount of water on Earth, it isn't. StuRat 05:42, 18 October 2006 (UTC)
Burning (or almost any other process in the troposphere) will have a negligible effect. There are however geological effects that sequeater water by reacting it with magmea to from other kinds of rock. In the very long term, this water will be recycled into he troposphere. Thare is a larger effect in the upper atmosphere. Sunlight "cracks" water into hydrogen and oxygen,and the hydrogen escapes into space relatively more easily than does oxygen. (sorry, no references: this is from memory of magazine articles from long ago.) - 70.177.166.201 00:20, 18 October 2006 (UTC)
Human evolution and immunity to venoms
editIt is oftern said that the most poisonous animals live in Australia. Our articles on venoms, i.e., animal poisons, seem to agree with that and also list quite some dangerous animals in South America. Here, in Europe, is is nearly impossible to meet animals with deadly venom, and also African and Asian animals seem to have a rather hard time killing a human. This looks to me as if the human body is well adapted to deal with the kind of poisonous animals to which the species Homo sapiens was exposed during the longest time of its evolution, which happened, as we know, mainly in Northern Africa and then spread out from there, South America being populated rather late and Australia very late. So, do you think that we humans have evolved the immunitary capability to deal with Old World venoms and hence, New World venoms are more dangerous? A counter argument would be if other large mammals were also more easily killed by, say, Australian snake species than be European ones, even if they are marsupials that evolved in Australia. Does anybody happen to know about this stuff? Simon A. 11:51, 17 October 2006 (UTC)
- I would argue that, over time, people killed off most dangerous animals in populated areas. For example, rattlesnakes are now being killed off in the south-west US (or at least those that can be found, which are the ones with loud rattles). People have a rather low tolerance for the existence of animals which can kill them. StuRat 14:13, 17 October 2006 (UTC)
- For that to hold true, humans must have wiped them out completely, which is rather unlikely. Humans may have eradicated quite a few se=pecies, but not the little critters that tend to be poisonous.
- Looking at the issue the other way around, why would spiders develop a venom that kills humans? They can't eat us. So it must be an unfortunate (for us) side-effect. So if that happened so often elsewhere, then why indeed did it fortunatley not happen in the places where humans evolved. Indeed, it sounds like too big a coincidence and I can't think of any other explanation. DirkvdM 08:48, 18 October 2006 (UTC)
- People definitely can kill off something like snakes, as is happening now in the rattlesnake example I gave. StuRat 14:28, 18 October 2006 (UTC)
- As is happening now. So hasn't happened yet. After thousands of years of cohabitation. QED. DirkvdM 18:24, 18 October 2006 (UTC)
- For most of human existence, what is now the US southwest was sparsely populated, because it's largely desert. Only quite recently has it started to become populated to the point where people would pose a threat to native species, due largely to the Hoover Dam, which provides sufficient water and power for people to live there. I will be sure to update you once the extinction is complete. StuRat 20:40, 18 October 2006 (UTC)
- Ok, point taken. But I was also alluding to the fact that we now have much better capabilities to track and kill animals. DirkvdM 07:56, 19 October 2006 (UTC)
End correction
editCan anyone please give me information regarding end correction in resonating air columns ? I would like to know what causes it and how it can be calculated . Thanking You.
- Tried resonance in pipes? Heres a nice link [3]--Light current 13:38, 17 October 2006 (UTC)
What frequency of microwaves can create an overpressure shockwave?
editMicrowaves, as i have heard can impart heat and momentum to air molecules, much like what happens in a shockwave during an explosion. The air is propelled into objects and as it is traveling it is heated up and expands causing even more pressure against what it hits. Does anyone know what frequency microwaves would be needed to create the same effect without useing chemical explosives? Is such a thing possible?
Robin
- Never heard of it, and the physics doesn't seem right. Microwaves could cause a water pocket to steam burst (mini boiler explosion), and this could cause a standard shock wave. --Zeizmic 16:13, 17 October 2006 (UTC)
Is there any kind of EM wave which could impart enough momentum to air to cause a shockwave, or heat air up enough, causing it to expand quickly causeing a shockwave? Robin
- Microwaves can't heat air to any significant extent. To absorb microwaves and heat up, a molecule needs to have a dipole moment. Almost none of the components of air have a dipole moment, the exception being water. Water has a dipole moment, which is why the water-rich food in your microwave gets hot, but the plate and air stay relatively cool. --BluePlatypus 22:47, 17 October 2006 (UTC)
- A photon obeys the relationship , where E is energy, p is momentum, and c is the speed of light. It's hard to compare different dimensions like energy and momentum, but c can generally be trusted to be "large" even though it can of course be written as , where d is "1000 times the speed of light". The point is that photons have much "more" energy than momentum, and so unless the energy is irrelevant somehow (as in a solar sail, where it is reflected) the energy effects will dominate. In this case, it simply means that you will turn the air into a violent, turbulent plasma that explodes simply due to overpressure long before you will do anything special pushing it around: the same light (of any variety) that heats a parcel of air by 1 Kelvin will only propel it at 105 meters per year. (Note that the same light can't do both; light in random directions can heat without propelling at all, but no light can propel without heating at all, due to relatively advanced conservation of momentum considerations.) And if you're content with heating the air, why bother with microwaves? TNT usually does the trick, or just a shorted-out capacitor if you want to stick to electricity. --Tardis 05:10, 18 October 2006 (UTC)
- Any EM radiation at sufficient intensity will produce a breakdown in a gas (air, in this case) and, in some cases, an outgoing shock wave. Breakdown is produced by ionization of gas (removal of one or more electrons from some or all gas atoms/molecules). Please see Electrical breakdown here for a quick review. A lightning is essentially an electrostatic breakdown of air (think of a low-frequency limit of your microwave field). A lightning produces a nice shock wave, too. At the high-frequency limit (IR or visible radiation), laser focussed in the air produces a "laser spark", which is an optical breakdown. An outgoing shock wave is produced in that case, too. Shock wave produced by a laser spark is spherical, and decays very fast with distance. Shock wave produced by a lightning is cylindrical, and decays much slower. Hope this helps. Dementios.
adding a word to search list
editHow do I add a link from an existing wikipedia article to a search list?
Specifically, the word 'Teazle' should be linked to the article Teazel (http://en.wiki.x.io/wiki/Teazel) and then appear with high relevence in a search-list for the word 'teazle'-- teazle is the more common spelling in the UK
John Barrs 17:14, 17 October 2006 (UTC)82.19.174.20
- You create a redirect, like this: Teazle. StuRat 18:08, 17 October 2006 (UTC)
- This is what it looks like:
#Redirect [[teazel]]
- I see that gave us a double redirect, so I changed it to redirect only once:
#Redirect [[dipsacus]]
Jogging and calorie consumption
editI ran for 20 minutes today at a slow pace. I guessed it to be about 4 miles per hour, but it could have been a bit faster. I weigh about 12 stone (168 pounds or 76 kilograms). Some questions:
a) How fast is a slow jog considered to be?
b) How many calories did I burn?
c) What is considered normal walking speed?
If I knew c) then I could work out how fast I run and then measure how far I've gone and my calorie consumption. Cheers!
- The rate of forward motion shouldn't matter much. Even jogging in place should burn up just as many calories. Note, however, that jogging uphill will make you do significantly more work than jogging in place or on level ground. StuRat 18:25, 17 October 2006 (UTC)
- Surely running at 7 mph burns more calories than at 4??
- Not if your arms and legs are moving about just as much, as in "power walking". StuRat 18:59, 17 October 2006 (UTC)
- It takes approximately the same calories to travel a mile at 1mph and 2mph, because it takes half as long. Calories per distnace run are approximately constant (note: approximately). RJFJR 20:05, 17 October 2006 (UTC)
"Jog" means to "run slow" in the first place. 4mph would qualify as jogging rather than running, and since it is quite easy to walk 4mph, you could classify it as a slow jog. People walk at different speeds, but 2 to 4 mph would be normal. -THB 22:22, 17 October 2006 (UTC)
- Try this calorie calculators:[this] and [this]. --Auximines 22:40, 17 October 2006 (UTC)
- Basically, if you make sure you have both of your feet off the ground at one point you're fine. Not doing so automatically classifies you as a walker, or a power walker. freshofftheufoΓΛĿЌ 05:31, 19 October 2006 (UTC)
solubility of capsaicin in edible oil
editI shall be extremely thankful if you can provide me the following information:-
- How much capsaicin is released from chili in edible oil in terms of percentage of the total quantity present when powder of chili is mixed in oil?
- What is the optimum time and temperature to get the maximum quantity of capsaicin released into the oil?
- Does green and dry red form of chili make a difference for the release of optimum quantity of capsaicin into the oil with reference to 2 above?
- Is there is a difference between the solubility of capsaicin and capsacinoids in oil?
Regards,
≠59.95.99.138 17:32, 17 October 2006 (UTC)S k sethi
- What kind of oil? Do your textbook have information on the solubility of capsaicin in oil? Surely your professor doesn't expect you just to know these things and the underlying info must be in your textbook. Get started on the problem and come back here for assistance. -THB 22:15, 17 October 2006 (UTC)
- This doesn't sound like a homework problem... Taking a look at Capsaicin#Capsaicinoids, I can see that they are all very similar. They have an identical ortho disubstituted benzene group and a hydrocarbon tail that varies only in length. The length of the tail will tend to increase its tendency towards hydrophobicity, making it more soluble in the standard oils used in food preparation. All of the tails differ by a carbon or two, so the degree of difference in hydrophobicity wouldn't be great. As for an optimum solubility of capsacinoids, the species of pepper you use shouldn't make much difference beyond the amount of capsacinoids they contain, so you could whichever pepper have the most in it; I would think that dry would be better, if only because it has more surface area when it's crushed, allowing for more efficient migration of the solute into the oil. Sorry I don't have any hard numbers. – ClockworkSoul 01:50, 18 October 2006 (UTC)
Feta
editThis question my be a bit dumb, but just why doesn't feta melt when hot like every other decent cheese? --Janneman 19:20, 17 October 2006 (UTC)
- it does get softer. my guess is it just has a higher melting point. try torching it!
- Hehe, that's agressive cooking! :-) —Bromskloss 22:23, 17 October 2006 (UTC)
- But not uncommon: Flambé. DirkvdM 08:55, 18 October 2006 (UTC)
- It's because it hs a low fat content. Englishnerd 21:06, 17 October 2006 (UTC)
Suicide pill
editIm looking for an easy and peaceful way out. i dont have the guts to throw myself off a bridge or anything like that. i was thinking about overdosing on over-the-counter drugs but im afraid that would cause slow and painful death or just make me realy sick. where can i obtain a suicide pill (doesn't have to be specifically made for that). i need something that would do it painlessly and easy to obtain (in Canada) or buy online.
p.s. please dont point me to suicide prevention bullshit cause those people are just stupid. my problem wont ever go away and im going to end this. its just a matter of how.. i dont want to have to run in front of a bus or something.
- What physical illness do you have? —Centrx→talk • 20:10, 17 October 2006 (UTC)
- It certainly is sad to hear that you want to kill yourself. Why do you feel that suicide is necessary? None of us here, and perhaps nobody where you are in Canada knows what you are going through, and certainly you are in a rough place if you want to kill yourself, but this is a decision that you will not be able to go back on. If you have a physical illness, have you had a second opinion? -a fifth opinion? Maybe someone here can tell you about research or give you hope for the future. Did you have a falling-out with a loved one? That is something that only time can heal, but YOU WILL FEEL BETTER as time passes.
- You asked that nobody point you to suicide prevention bullshit, and I will honor that, but have you considered seeing a psychologist of psychiatrist? You wouldn't even have to tell them that you were suicidal, and sometimes just talking helps.
- Nobody here is going to tell you how to kill yourself. Even in this tiny community which represents a tiny portion of a corner of the internet, you would be missed. Your addition to this help desk, in the Feta cheese article above, helped us out, even if it was just a little bit. Please take care of yourself, do whatever you need to do to get yourself feeling better, and find help. And if you need help finding help, just ask; ask us, ask a doctor, ask someone. I think I speak for all of us when I say I hope we hear from you again.Tuckerekcut 21:07, 17 October 2006 (UTC)
- I've had some really tough bad things and loss happening in my life in the past, and I've felt suicidal, but now I'm reasonably happy. Try studying the stoic philosophy. Get more detached from life, don't take it so personally. Try helping others.
- Antyhing that makes you want to kill yourself isnt beneficial to you, so whatever your problem is, its hurting you to worry about it that much. So yeh I'd recomend speaking to someone with wisdom in this area about your problems. Philc TECI 22:09, 17 October 2006 (UTC)
Unfortunately, an overdose can screw up and leave you brain-damaged or in a coma. It would be interesting to know what is so irrevocable and permanent and it would help answer your questions. -THB 22:12, 17 October 2006 (UTC)
- The classical resource is Compassion & Choices, formerly known as The Hemlock Society, but I think you'll find they're more focused towards people who are near the end of their lives due to medical problems. Like everyone else here, if that situation doesn't apply to you, I'd encourage you to seek other help than theirs.
- Are you *absolutely* sure that you want to die? A long time ago, I thought I did too. I got drunk and sat on my bed with my revolver, playing Russian roulette. Five clicks and nothing. When it came to pull the trigger for the sixth time and face a 1/1 chance of a bullet to the head, I just couldn't do it. My finger literally wouldn't pull the trigger, no matter how hard I tried. It was only then that I realized that there was a part of me inside that really wanted to live. --WineBob 23:07, 17 October 2006 (UTC)
There is another way to leave your problems behind, just get up and leave. Go somewhere where nobody knows you, your past, or your problems, and start life over. Of course, this doesn't apply if your problem is a terminal disease, but applies to just about anything else. You might say you would feel guilty about leaving everyone you know, but you would be doing that anyway if you killed yourself. You can either tell people you are leaving or just skip out of town, your choice. StuRat 00:06, 18 October 2006 (UTC)
The loss of you would greatly diminish each of us. Everyone I know has had times when it didn't seem like life was worth living: your loved one is gone, or the job is lost, the stress is too great, or the health is impaired. But we have found that as time went by, other things came along which made life worth living. Don't give up. Medication can help you get out of the biochemical pit of depression. ""All mankind is of one author, and is one volume; when one man dies, one chapter is not torn out of the book, but translated into a better language; and every chapter must be so translated...As therefore the bell that rings to a sermon, calls not upon the preacher only, but upon the congregation to come: so this bell calls us all: but how much more me, who am brought so near the door by this sickness....No man is an island, entire of itself...any man's death diminishes me, because I am involved in mankind; and therefore never send to know for whom the bell tolls; it tolls for thee." John Donne. Edison 05:39, 18 October 2006 (UTC)
- Not quite a faq, but it's been asked before, when I recommended taking a heroin overdose. But I also suggested something like what StuRat said. Moving elsewhere might take away the reasons you now have to kill yourself (depending on what they are). But to expand on that, if you've already made up your mind, then basically you're already dead. That opens up a whole new range of possibilities. You can now do whatever you like. Who cares? You're dead already, aren't you? So sit down and think what you would really like to do. No inhibitions, just go for it. With some luck you'll like it. DirkvdM 09:21, 18 October 2006 (UTC)
- I personally knew someone from high school who tried to kill himself by jumping on a railroad. I believe that the main thing that drove him to do it was stress at university. He didn't manage to kill himself, but did lose an arm. He since made a recovery from being suicidal, and is now making something of his life, pursuing a career as an artist. When I got to meet him at a high school reunion a few years ago he seemed to have a very positive outlook, though obviously he'd be better off now if he still had both his arms. Now obviously I don't know what you're going through, but still I think there's a lesson from his experience that may be applicable more widely, and maybe to your situation: that however much suicide may currently seem to you like the only option, suicidal feelings can be a passing phase, and the less damage you suffer in the meantime the better it will be for you in years to come. All the best to you — you're worth it. Arbitrary username 12:47, 18 October 2006 (UTC)
- Actually, the lost arm may have been the shock that made him change his life. Not that I'd advise the questioneer to cut off his arm, though. :) DirkvdM 18:29, 18 October 2006 (UTC)
- P.S. I see you posted a separate message about how to use your phone as an MP3 player. (At least I assume it's your message; it was posted from the same computer just a few minutes earlier.) I'm really sorry I don't have the answer to that question. But obviously you enjoy listening to music. That's great. As you're feeling down at the moment, I reckon now's a good time to treat yourself. Go out and buy yourself a recording from one of your favorite groups / composers / whatever. Arbitrary username 13:08, 18 October 2006 (UTC)
- Are you really so intent on ruining the lives of your friends and family? Do you really want to be the dagger in the hearts of those who put you in this world and brought you up? Is that not quite selfish? I beg you to read the Gospel (start with that of Matthew) and realise that there is much joy to be had if you so wish. God bless you, 82.65.102.5 12:57, 18 October 2006 (UTC)
- Blimey! If he weren't suicidal already, he'd be now. After all this crap I wonder if he's still reading this. DirkvdM 18:29, 18 October 2006 (UTC)
- Ah, religion. The thing that gives you false hope by bringing you into a denial. Also: "If you don't do this and you don't do this, you'll be tortured forever in a place called hell." Now I really want to die. --Bowlhover 19:34, 18 October 2006 (UTC)
- Yeah all this feely emotional crap is a little goober but "getting religion" is pretty much the stereotypical turnaround for suicidals so don't discount its effect --frothT C 19:10, 18 October 2006 (UTC)
- He's right; religion might not be the answer for most of us (especially here on RD), but there are loads of people that manage to find their happiness in that little book, and who's to judge them for that? I for one don't see the problem with at least one plea to "find Jesus, Mohammad, or Buddha" among all of the other comments. Heck, he's probably a lot more likely to be picked up by some psycho cult with his mindset, so the least we can do is point him towards someone (a priest, rabbi, monk, or imam) who might make an honest effort to help him. freshofftheufoΓΛĿЌ 05:26, 19 October 2006 (UTC)
- He specifically stated he didn't want any of that sort of help. Also, religion might just as well turn him off. The fact that he comes to the Wikipedia ref desk says something about him. And the science ref desk no less. Like you said, people here aren't generally into religion, and that may be precisely what he was looking for. Also, Bowlhover is amongst us probably the greatest expert on this subject. DirkvdM 08:09, 19 October 2006 (UTC)
- And if he's such an expert (I wouldn't know, I haven't read anything he's done yet) then he'll know for a fact that religion is a very powerful drug for a huge percent of the human population (as much as I hate to believe that). The original questioner also gave no such specific request, and if you haven't noticed, nobody is answering his question and telling him where to get a "suicide pill", so anything seems game to me. I also don't remember the science desk restricting answers to scientific perspectives, never mind that his question has absolutely no scientific basis; it should be in the "misc." section, though we all understand his motivation for putting it here. I'm not trying to support any sides here, I just don't think the anonymous editor should be bashed for trying to help in his own way. Compared to a lot of the zealous stuff there is on the web I'd say he was plenty mild about it. freshofftheufoΓΛĿЌ 10:09, 19 October 2006 (UTC)
- Bowlhover's experience lies in him having gone through the same thing and having asked pretty much the same question at the ref desk. Just check out his talk page. You can't beat that sort of expertise (except maybe Winebob). And do we all understand his reason for putting it here. Your interpretation of that is obviously not mine. And someone did answer his question, namely me. But some arsehole removed that. So I put it back again. DirkvdM 14:26, 20 October 2006 (UTC)
- I agree with the heroin suggestion; a handful of sleeping pills + alcohol would also work. A handful of tylenol plus alcohol would probably work too, but that would require more investigation. Anchoress 23:29, 19 October 2006 (UTC)
- Well at least other people are still humane. (@Anchoress) And @ 82.65.102.5, you don't point someone to an advanced cookbook if they don't even know how to cook, don't you?
@anon who posted death notice: Death is something like...KFCd. The advertisements of it are present in movies, TV programs, and books. It looks so tempting and it looks if it is the only solution to problems. But hey, there's healthy food. There's water instead of the drink of death - Coke (sorry Coca Cola company) And if you presist to have those wholesome things in life instead of KFC/suicide, you will eventually look back and say: "Hey, WTH was I thinking! KFC fried chicken contains 10000kJ!~" ;) Hope you decide to stay. --inky 07:57, 20 October 2006 (UTC)
- IMO what's inhumane is having a double standard about suffering. I've had three suicides in my close circle, and numerous other deaths of beloveds, thru accidents, old age, and illness. I've also witnessed people soldiering on despite agonising pain (mental, psychic and physical). Death sucks. Grieving sucks. Feeling like someone is suffering so much that they want to leave this world sucks. But some people have just suffered enough. I don't know if this guy is one, but he asked a question, and IMO either we decide as a community that these kinds of questions are too hot to handle (or suspected trolling or whatever), or we answer them to the best of our ability. Many of us have answered by trying to problem-solve the person's issues or trying to talk him/her out of it. Others just answered the question s/he asked. Each according to our gifts.
- I think it's unbelievably sad if this person is genuinely in the place of feeling there is no future for him/her in this world. But I think it's equally sad if they stick around because we as a society can't recognise the intractibility of relentless psychic suffering. Sometimes it doesn't get better. Few of us would try to talk someone out of killing themselves if they said they'd experienced unbearable physical pain for years and years, without any help or relief, and were just so tired of it their life wasn't worth living. But when it's mental, emotional or psychic pain we resort to hope, faith and platitudes. When we say 'Hang in there, it'll get better eventually', sometimes we're right. But it's still the choice of the person suffering, if they get tired of waiting and trying and hoping. It SUCKS, all death and suffering and grieving sucks, but sometimes mental suffering is unbearable. And maybe it's not our place to tell or even encourage someone to try to bear it. Anchoress 03:48, 21 October 2006 (UTC)
- I respect your opinion, and I myself don't mind if we get comments from both sides, as long as everyone is well-stated and speaks honestly. I think there is a differenciation to be made between people who give hollow claims like "it will get better", and those who actually try to help. Imagine visiting a poor village in Sudan filled with starving boney children, patting them on the head and telling them "don't worry, it'll get better". That's bullshit, but what would really make more sense is to say, "OK, let's get you out of here and try the life life thing again in a country where you might have a small chance of living past 16". Most of those kids lack the means, will, and knowledge to be able to do something like that, and this guy probably does to. The least I figure I can do (and it seems a few others feel the same way), is to offer him the knowledge, show him a means, and maybe that will cause some measure of will to emerge in his troubled mind. freshofftheufoΓΛĿЌ 04:02, 21 October 2006 (UTC)
- Not to belittle your problems, but if you're not desperate enough to endure some pain, then you're probably not desperate enough to kill yourself. People who are at the point of suicide have already endured enough torment so that any physical pain before the end is not enough to discourage them. I suggest that since you're not truly ready to kill yourself (and also, you're obviously reaching out to a vocal community instead of just Googling a few methods yourself), you should seek professional help for the pain that you are already enduring, before you try something that you can't take back.
You can try using painkillers or antidepressants. But whatever drug you decide to use, make sure to swallow as much as you possibly can. You may think "oh, I've taken ten times the normal amount, that should be enough to kill me", but if it doesn't, it will be very painful.
I know that many people who are dissuading this question's poster from suiciding are doing so in good faith. However, I also know that the poster has thought of everything you've said. The only way his mind is going to change is if things improve for him. If things don't improve, letting him suicide is the only humane option. --Bowlhover 02:19, 23 October 2006 (UTC)
Purpose of Viruses
editWhile some bacteria are harmful, most bacteria serve a beneficial purpose. Higher lifeforms would not exist on earth without the presence of helper bacteria. Viruses on the other hand seem to be, at best, innocuous and, at worst, highly destructive. What biological purpose do viruses serve (other than killing off the weak)? Are there any "good" viruses?
- "Purpose" is all in your mind, or at best an observed side-effect of "living things reproduce" and "living things adapt to utilize the resources and conditions that are available". DMacks 20:24, 17 October 2006 (UTC)
- Thinning the herd? Ƶ§œš¹ [aɪm ˈfɻɛ̃ⁿdˡi] 20:28, 17 October 2006 (UTC)
- No 'life' if you include viruses in that serve any purpose, they are just chains of chemicals created through coincedence that in the enviroment they were in somehow self replicated, variations through mistakes in this process led to variation, ones that couldnt replicate died, those that could survived. Thats life and evolution for you, on an incredibly basic level though. Philc TECI 20:42, 17 October 2006 (UTC)
- Then why have bacteria evolved synergistic relationshipship with other life forms but viruses have not?
- Because of the way we define them, virusses by definiton of the term, have no means of self reproduction, and so, in all cases I know of, hijack and destroy a host cell instead, it is very dificult to have a relationship with a parasite, when all this thing is capable of is destroying your cells. Keeping in mind, virusses aren't complex enough to perform any other functions than replication. Whereas bacteria are complex enough organism to perform some (sometimes useful) function in their life span, and reproduce without killing host cells, this makes them far more useful. Philc TECI 22:06, 17 October 2006 (UTC)
- We have been using Bacteriophages for years, but have proven less effective than antiobiotics, but such things could be deemed as synergistic, in a sort of common enemy sort of way. Philc TECI 22:37, 17 October 2006 (UTC)
- It doesn't make a lot of sense to ask "why" a given evolutionary result has not been seen. Maybe there's no good route from "where life has been thus far" to where you want to go; but maybe in the future it might. Maybe we just isn't imaginative enough to figure out an evolutionary niche for something...Nature and random-chance/trial&error are sometimes at least as smart as scientists:) What if one virus protected us from some other worse virus?[4] DMacks 22:15, 17 October 2006 (UTC)
Viruses move genes around and thus provide a source of diversity to then be acted upon by selection; ie they speed up evolution. However the words 'good' or 'bad' do not apply. --GangofOne 20:59, 17 October 2006 (UTC)
Some viruses are desirable: Good Viruses -THB 22:09, 17 October 2006 (UTC)
- Viruses have also given us wonderful ways of studying the structure of proteins and DNA. So maybe that's their higher purpose. ;-) --Fastfission 22:15, 17 October 2006 (UTC)
In the future, we may be able to change our genetic codes using a virus to deliver the new DNA. This is obviously quite dangerous, but could be enormously beneficial, as well. StuRat 23:54, 17 October 2006 (UTC)
- As to why viruses have never developed symbiotic relationships with host cells... some have speculated that the evolutionary origin of the intracellular organelles of eucaryotes is as a symbiotic viral infection...--Mark Bornfeld DDS 00:01, 18 October 2006 (UTC)
"they speed up evolution. However the words 'good' or 'bad' do not apply" <-- The term "good" is used here in the context of what is beneficial for virus-infected organisms. Theoretical biologists such as Stuart Kauffman have discussed the importance of evolvability as a trait. In addition to playing an important role in the rate of evolution, some hypotheses suggest that viruses played a fundamental role in the origin of cellular life as we know it; see: Three RNA cells for ribosomal lineages and three DNA viruses to replicate their genomes: A hypothesis for the origin of cellular domain by Patrick Forterre. --JWSchmidt 01:51, 18 October 2006 (UTC)
"Why does X exist?" is a teleological question. It exists. Edison 05:42, 18 October 2006 (UTC)
Lets all be honest here. The guy asked you not to try and chage his life. Leave him alone. He obviously has issues that we could all never relate to, so be it. Let him die. Its of a waste of your time trying to fight for him. Thats one less person in the wrold to clean up after and lets hope his repalcement has a positive out look on life. Serisouly if I was you, i'd pump myself up on drugs and shoot myself in the head.At least before I die, the world will look a but prettier.
Sorry brew, i wanna help, but its uselss. I know from personal experience.
Signed 195.14.68.69 09:07, 23 October 2006 (UTC)realistic thinking195.14.68.69 09:07, 23 October 2006 (UTC)
What does cannabis smoke smell like?
editI'm wondering if someone I know smokes it. The smoke is somewhere between the smell of tobaco smoke and incense sticks. I'm not going to turn her over to the cops, just curious.
- She could also be smoking Kreteks or another type of scented cigarette. The fragrance of cannabis depends greatly on what type and form is being smoked, but the odor is usually more pungent than that of incense. It could also be a combination of (cigarette) smoke and the air freshener she's using to mask the smell.---Sluzzelin 22:00, 17 October 2006 (UTC)
- It has a unique smell, very hard to describe, and it can vary, as above. I also agree that it sounds more like a clove cigarette or even a bidi.
- Have you considered asking her if it is marijuana smoke? You'll be able to tell whether she tells the truth or not. -THB 22:05, 17 October 2006 (UTC)
- She may just be burning inscence sticks to remove the nasty smell of the tobacco smoke. Cannabis has a very distinct pungent smell, it would be difficult to think that anyone would be deliberately making that smell, so I doubt any inscence sticks smell like it, however, they are regulalrly used to mask its use, as with normal smoking. Philc TECI 22:30, 17 October 2006 (UTC)
I think she would be very unlikely to smoke any kind of scented cigarette, clove cigarette, or bidi. I don't want to ask her as she would think I was being hostile. Does cannabis smell unpleasant, or pleasant? What exactly is meant by it smelling "pungent" for example?
- It is an extremely dense, sickly-sweet smell, not a thousand miles from the smell of sweat in many cases. If you think you smell weed, chances are you do.
- Yeah, in my college-dorm experience, as the smell gets stale it starts to resemble a sweeter form of B.O. It also smells more like burning vegetation than tobacco. I know that the police dept. sometimes burns a little for educators and other law-enforcement so that they can know what it smells like - maybe if you are some sort of authority figure you could ask them for a small demonstration. Once you identify it, you'll smell it everywhere...
It has been described as the smell of burning leaves. Expensive pot, like the smell of expensive burning leaves.Edison 05:43, 18 October 2006 (UTC)
- Or rather burning flowers, because that's what it is. Marijuana, that is, which indeed smells rather sweet (in the literal sense). But hasjisj has a much sharper smell. Are there no 'coffee shops' or such where you live, where you could go and have a sniff? DirkvdM 09:42, 18 October 2006 (UTC)
- In my opinion, if it smells like tobacco at all, it's not pot. They smell quite different. ike9898 23:51, 19 October 2006 (UTC)
EM wind
editI heard something on this before, but am still not sure so shall just ask directly and to the point, Em waves can cause momentum transfer with air molecules right? so that means that it is , at least in theory , possible to create EM wind, that is, air currents caused by interactions with Em waves. Is this correct?
- I'm not an expert, but I don't see why not. --Allen 23:14, 17 October 2006 (UTC)
- Yes; if you shine a strong laser through a sealed glass box, you will get a small current flowing along the laser beam (then around the sides of the box back to its entry point) because of the recoil from the slight absorption in the air. But you will also heat the air so affected, and I would not be at all surprised if the resulting convection entirely swamped the effect of radiation pressure on the air. Does that help? --Tardis 04:27, 18 October 2006 (UTC)
- Ayup. Compare Crookes radiometer (thermal effects) to Nichols radiometer and solar sail (radiation pressure). DMacks 04:36, 18 October 2006 (UTC)
So of this is possible then a EM caused overpressure shockwave would be possible as well if the air could be accelerated to supersonic speeds right? Robin
- Yes, but one would have to ensure that all the light is absorbed in a small region of air, which is practically impossible. Perhaps microwaves and steam, but not air. A very high-intensity laser might be able to do it as well (ie, the beam is high-powered enough to heat the air to the necessary conditions despite being of low absorption), but consider that the overpressure wave would then originate at the EM source, which pretty much rules out any practicable applications (not to mention the extreme energy required, due to air's absorption being so low). I'm pretty sure it can't be practically done with today's technology (high-intensity laser pulses are quite small, at which scale the overpressure effect no longer applies).
They actually already have a laser which does this its called pulsed impulse laser, its on wikipedia, they wanna use it for crowd control, but i think this combusts air which propells air around it rather than adding momentum to it or causing air to heat then expand propelling air around it like an explosion, it actually causes an explosion rather than just the shockwave.
protozoa - animal report
editHelping with a forth grade report and have had problems finding the run donw from kigdom to species. Kingdom, phylum, class, order, family, genus, species, common name? I would appreciate any help.
- Our articles on binomial nomenclature, taxonomy, and Linnaean taxonomy ought to get you started. TenOfAllTrades(talk) 23:08, 17 October 2006 (UTC)
- Did you read our protozoa article ? StuRat 23:46, 17 October 2006 (UTC)
Equine Medicine
editI own a 5 year old thoroughbred mare who is presently in training for horse racing. At home she behaves well and even though she had an older mare in the next paddock does not come into season. However as soon she is placed in a professional training environment with other horses, particularly indoors, she immediately comes into season and begins behaving very badly. We have tried deprovera injections without success. I have heard that implanting a glass marble in the uterus can help. Does anyone out there have any knowledge of this problem and possible remedies?
Your help would be appreciated.
Regards
Tony
- Maybe equinechronicle can give you some more information on treatment in general. It says the mentioned marble technique lacks references in scientific literature, but Equisearch quotes a study conducted at Auburn University with partially positive results for the method of placing a glass ball in the mare's uterus. Though this technique sounds invasive, no damage was found in the mares' uteral tissue upon removing the glass marble after three months.---Sluzzelin 01:25, 18 October 2006 (UTC)
Many thanks. This is most helpful. Mumzwon 03:05, 18 October 2006 (UTC)
Sorry about the apparent name change. I am a first time user and just learnt how to sign my user name (which, by the way, is the racing name of the horse). Regards Tony. Mumzwon 03:09, 18 October 2006 (UTC)
- Please note that people answering medical, legal, or veterinary questions on Wikipedia may have no qualifications whatsoever, and you are always advised to consult an appropriate expert in the field in question. Good luck with your mare. Edison 05:47, 18 October 2006 (UTC)
Thinking
editIs it harder to think straight/remember things when you have a cold?--Light current 23:39, 17 October 2006 (UTC)
- When I have a head cold I just have problems staying awake and problems with external stimuli. That could be a problem. Lots of orange juice for you Mr. Light Current. AMP'd 00:02, 18 October 2006 (UTC)
- Maybe not so much for the reason that you have a cold but more consequential of symptoms such as fatigue. IMO, it's a bit hard to concentrate on a test if you're all about your runny nose, your sneezing, your coughing, etc and unable to focus completely on the task at hand. Thinking straight - might be difficult with lack of focus. Remembering things - it's not in my common knowledge that physical symptoms (aside from distraction) would change the way you retrieve information from the brain, but I'm no expert. Sybil Gray 00:03, 18 October 2006 (UTC)
- On the Red Square (Krasnaya Plochad) , James sneezed. He extended his hand towards the blonde russian spy's and began : - My name is ..." -- DLL .. T 19:01, 18 October 2006 (UTC)