Wikipedia:Reference desk/Archives/Science/2010 April 3

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April 3[edit]


1. Whats the known cure for sinus? —Preceding unsigned comment added by KENNEDY NEWTON (talkcontribs) 01:25, 3 April 2010 (UTC)

The Paranasal sinuses are the large spaces between your nose and your throat. They aren't cured because they are not a sickness or disease. They are just big cavaties inside of your skull. Sinusitis is a situation when your sinuses become inflammed when you have a cold or have allergies like hayfever. Wikipedia is not the place to go for medical advice. You are free to read our articles about these topics, but if you are having sinus problems, see a doctor in person. They can help you. --Jayron32 01:40, 3 April 2010 (UTC)

Baseball physics[edit]

Hey all. My bio prof said something the other day that I think wasn't quite right. Consider a baseball. If it has a velocity of 90 miles/hour west, and it was hit by a bat with 100 mph (east), how fast (east) would the ball move? The prof said 190mph, but how could it be greater than either speed? THX (talk) 01:44, 3 April 2010 (UTC)

The reason is is because the heavy bat has a lot of energy swinging (as anyone who has been hit by one can tell you). When the heavy bat hits the relatively light ball, all the energy it took to move a heavy bat at 100 mph now goes into a ball that weighs a few ounces. It takes less energy to move the ball than the bat, so when the ball receives the same amount of energy that it took to move the bat, it goes much faster. --The High Fin Sperm Whale 01:49, 3 April 2010 (UTC)
This is how to think of it. If we assume that the bat and ball are part of an elastic collision (read that article), it means that the energy is conserved in the objects colliding. Certainly, a small amount of energy is lost (sound and heat mostly), but its not a bad approximation. If the energy of the ball-bat system is roughly the same before and after the collision, then almost all of that energy is part of the combined system is transfered to the ball. I'm not sure where the 190 mph comes from; energy should be additive, and not velocity, but yes, the ball SHOULD be moving faster by itself than either was moving before the collision. Since we assume elasticity, then the direction doesn't matter; energy can reflect and change direction just fine. --Jayron32 02:04, 3 April 2010 (UTC)
Both bat and ball have a little elasticity - so that much of the kinetic energy from the westbound motion of ball goes into bending the bat and deforming the ball. As the ball heads off in the opposite direction, both bat and ball un-deform - giving back much of that energy. Hence, the ball can leave the surface of the bat and get that extra 'kick' at the end. SteveBaker (talk) 02:05, 3 April 2010 (UTC)
Ok, I know that the ball is moving faster after the collision, even if only due to the difference in energy the ball has and the bat has. But where did my prof get 190? It seems like an arbitrary mathematical operation. If we set values for the masses of the ball and bat (let's call them x and y, respectively) how would we figure out how fast the ball was actually going after the collision? (talk) 02:13, 3 April 2010 (UTC)
I'm assuming he simply added the 90 mph from the ball and the 100 mph from the bat, and got 190 mph (90 + 100). In general, you can't add velocities. While issues of special relativity only show up at really high speeds, you still can't do it at low speeds, because velocity is not the conserved quantity, momentum and energy are. (Even if velocity was conserved, it wouldn't be 190mph, as the bat still has forward motion after it contacts the ball.) I was going to mention the Galilean cannon as a cool demonstration that velocities are not conserved, but I can't seem to find reference on Google to the usage. As I recall it, it's a stack of steel spheres of increasing size dropped down a tube. When they hit the bottom, the smallest (top) sphere get almost all of the momentum from the stack (as in Newton's cradle) and goes shooting off. Is this actually called something else? -- (talk) 02:42, 3 April 2010 (UTC)
I agree. The 190 mph does seem a bit random. It doesn't seem to have any basis in real calculations. What you would need to know is the speed of the bat, the mass of the bat, the speed and mass of the ball, and the amount of time they are in contact with each other in order to calculate how much energy is likely transfered to the ball. It would only be by a bizare coincidence if the ball leaves at exactly the sum of their velocities. You can do a simple experiment to show that velocity is not additive in this way. --Jayron32 02:29, 3 April 2010 (UTC)
Jayron, the contact time is neither necessary nor very useful. The coefficient of restitution is the extra piece of information required to solve that kind of problem. Dauto (talk) 02:54, 3 April 2010 (UTC)
This study takes into consideration bat speed, weight and coefficient of restitution. caknuck ° needs to be running more often 03:17, 3 April 2010 (UTC)
(edit conflict) Assuming an elastic collision, and ignoring the effect of the person swinging the bat, then the ball, from the reference frame of the center of mass, appears to enter and leave at the same speed before and after the collision (momentum and energy are conserved). If we approximate the bat as infinitely massive (or significantly large compared to the ball), then the center of mass reference frame is just the reference frame of the bat. In that case, the ball, from the bat's point of view, enters at 190 mph, and so must leave at 190 mph. Adding that to the bat's 100 mph, we get the ball traveling 290 mph in the stadium reference frame. That's obviously not a good answer (the collision's not elastic, the bat's not infinitely massive, etc.), but the 190 seems to come from nowhere as well. Buddy431 (talk) 03:30, 3 April 2010 (UTC)
Assuming the (lets say ~35 ounces (0.99 kg)) bat loses 10 m/s its velocity of 100 miles per hour (45 m/s) through the collision with the .145 kilograms (5.1 oz) baseball traveling at 90 miles per hour (40 m/s), then:

28.28 metres per second (63.3 mph) = the ball's final velocity? I think I need more help than the professor...what'd I do wrong here? If no one corrects this by morning, I'll get out my physics book and redo this. Ks0stm (TCG) 05:22, 3 April 2010 (UTC)
Why would you assume that? Dauto (talk) 06:44, 3 April 2010 (UTC)
The "Astro-blaster" is the modern version of theGalilean cannon that '174 mentioned above (which - surprisingly - isn't named after Galileo - but after the city of Galilee). I guess the original has a stack of balls inside a tube - the modern version has four balls threaded on a wire. Ranging from a large/heavy one at the bottom through consecutively smaller and lighter balls to a small one at the top. You drop this contraption so that the big ball hits the ground and the topmost ball will rebound with a spectacular amount of speed. So much so at they have to sell the gizmo with safety goggles! An even simpler way to demonstrate that "conservation of momentum" most certainly doesn't mean "conservation of velocity" is demonstrated in this YouTube video - which is essentially a Galilean cannon with just two balls. It's hard to believe that we don't have an article about this stuff - but it's tough to find details for anything other than the modern version. SteveBaker (talk) 16:35, 3 April 2010 (UTC)
(I created a Galilean cannon could use some expansion). SteveBaker (talk) 03:07, 4 April 2010 (UTC)
Your 3rd ref just seems to be floating out in space. StuRat (talk) 03:13, 4 April 2010 (UTC)
Can I ask an unrelated question here? It may not be completely unrelated. Let us say a baseball is pitched fast — a fastball. Let us say a batter hits a powerful line drive off the fastball, almost directly back at the pitcher — let's say several feet over the pitcher's head. It is a very powerful shot and it is an out-of-the-park home-run. My question is: Is the ball ever at rest between making contact with the bat and sailing off over the pitcher's head? To phrase it differently: Does the ball's motion in one direction involve coming to a complete stop before embarking on its motion in virtually the opposite direction? Bus stop (talk) 03:30, 4 April 2010 (UTC)
This is a version of the fly-and-train paradox (it probably has a better name - but I don't know what it is). The idea is that there is a teeny-tiny housefly heading east along a railroad track which hits a train heading west. Since it seems obvious that there must be a moment when the fly goes from travelling at 10mph to the east to moving at 60mph to the west, there must be some moment at which the fly is stationary...but since it's in contact with the front of the train - then surely the train is also stationary at that moment! Why doesn't train react to hitting the fly in the same way it would if it hit a 500 ton, stationary, solid steel barrier?
The reason this isn't true (and the reason why we wouldn't say that the baseball was ever strictly speaking, "stationary") is because neither flies nor locomotives nor bats nor baseballs are perfectly rigid. So the object doesn't reverse direction instantaneously as a solid lump - it does it atom by atom. So it's perfectly possible for individual atoms to slow down, stop and the reverse direction without the entire object seeming to do so. At the necessary low level of visualisation, everything is very elastic and bendy. SteveBaker (talk) 04:14, 4 April 2010 (UTC)
Thank you for that response. Let me try to pose another question (or two). I'm not sure this question makes sense, but here goes:
If two atoms, or subatomic particles, collide, head-on, both of which are traveling in exactly opposite directions, both of which are of equal mass — how do they behave in ways relating to the collision? Do either or both of them reverse direction? Do either or both of them spend a duration of time at rest before resuming travel? Bus stop (talk) 11:03, 4 April 2010 (UTC)
At the atomic level, Quantum theory dominates what's going on and the simplistic ideas we have about large-scale objects like trains a baseball bats become fuzzy and uncertain. In particular, once you invoke quantum theory, it is meaningless to talk about a particle having both an exact position and an exact momentum because of the Uncertainty principle. Hence you cannot ask whether two atoms "collided" (meaning that their positions are known to be adjacent) and also know what their speed is. If you wish to talk about whether the atoms are stationary or not - then you can't talk meaningfully about their positions. At this level, atoms are fuzzy probability clouds that can't be pinned down enough for this question to even have meaning! This is an annoying final resolution to an interesting paradox - but that is how the universe works. SteveBaker (talk) 17:00, 4 April 2010 (UTC)
Surely a small amount of energy is also lost to the bat, batter and ground as vibrational energy, and some should also be lost from the ball as thermal energy due to the elastic friction and expansion of the ball during and after collision? And let's not forget about air resistance (and why is your biology prof teaching baseball physics?). ~AH1(TCU) 23:18, 4 April 2010 (UTC)

Psychological reaction[edit]

What is the name of that feeling that one gets when their worst fears or suspicions are (actually, seemingly, or falsely assumed to be) realised? Thanks. ~AH1(TCU) 02:26, 3 April 2010 (UTC)

Life. --Jayron32 02:29, 3 April 2010 (UTC)
A self-fulfilling prophecy ? StuRat (talk) 02:57, 3 April 2010 (UTC)
Dread seems about right to me. --Anonymous, 04:09 UTC, April 3, 2010.
Horror and terror seem close, as does fear itself at the resulting situation, and fight or flight response would be the associated physiological response. Ks0stm (TCG) 04:26, 3 April 2010 (UTC)
A sinking feeling? --TammyMoet (talk) 10:28, 3 April 2010 (UTC)
Concurred! Vranak (talk) 12:05, 3 April 2010 (UTC)
As an example of this I find this line by E. Annie Proulx:
"She fought her way forward, seven, eight feet, her heart hammering, so intent on reaching the other side of the gully she felt only astonishment when the fatal aneurism halted her journey."
That is from Postcards (novel). Bus stop (talk) 03:40, 4 April 2010 (UTC)

RGB color ranges for human skin, nails, hair, and eyes[edit]

Please see RGB color range for human skin and the next three questions at Wikipedia:Reference desk/Computing.
-- Wavelength (talk) 06:02, 3 April 2010 (UTC)

I already have. And on the Humanities desk. Why do you think it necessary to post to so many reference desks? --Phil Holmes (talk) 11:59, 3 April 2010 (UTC)

Body aches and massage[edit]

It is commonly seen and experienced that general body aches and soreness feel better with simple massage. How does massage help with body aches and general soreness? Shivashree (talk) 07:11, 3 April 2010 (UTC)

When I trained as a masseuse, I was told it is partly due to the increased blood flow to the tissues brought about by the movements of the hands on the body, which breaks down things such as lactic acid and makes it easier for the blood to carry it away. It's also partly due to the relaxing effect of repetitive movements on the muscles and on the brain, and this relaxation restores equilibrium in the affected tissue. The heat generated by the friction of the massage will also relax the body. All this will stimulate the production of endorphins which are natural painkillers, and also produce a degree of euphoria. --TammyMoet (talk) 08:08, 3 April 2010 (UTC)
Plus, we are still monkeys, and grooming has its pleasures. --Ludwigs2 16:34, 3 April 2010 (UTC)
I was thinking of saying something like that but didn't bother, but you put it more succintly anyway. Of course it's unclear how much this will apply if we're referring to something like a massage chair with no other human involvement Nil Einne (talk) 17:26, 3 April 2010 (UTC)
well, massage chairs don't work nearly as well. it's something in the physical contact with others, I think. interestingly, in orangutans (or is it gibbons, I forget), the lead male in a troop is significantly larger and has a noticeably different coloration than beta males, and both the size and coloration differences have been traced to the fact that alpha males get much more grooming attention from females. It is not an insignificant behavior. Face-smile.svg --Ludwigs2 17:55, 3 April 2010 (UTC)
I think that the nerves that transmit pain, and touch are the same nerves. If you use the nerves to transmit touch they can't transmit pain at the same time, so you don't feel the pain. This is why rubbing a "boo boo" works so well for kids. Massage presumably does the same thing, but in deeper tissues. I think that once the pain sensation stops it doesn't start up again right away, or maybe the nerves get "exhausted" and don't transmit for a while. Ariel. (talk) 01:14, 4 April 2010 (UTC)
Oh, thanks everyone, especially TammyMoet for your answers. Shivashree (talk) 04:04, 5 April 2010 (UTC)

Cute animals with bad attitudes[edit]

Can anyone provide me with some examples of animals which appear cute to humans but in reality have an extremely bad-tempered and violent nature? An encounter with someone's small, fluffy but hateful (even the owner agrees) little lap-dog yesterday got me thinking about this. -- (talk) 08:17, 3 April 2010 (UTC)

If you want your living room rearranged, perhaps you can try these cute ones. DVdm (talk) 09:32, 3 April 2010 (UTC)
Wolverines could be cute. Staecker (talk) 11:44, 3 April 2010 (UTC)
Monkeys are often very cute and can be extremely violent, especially when they are protecting young. The Barbary Macaque (sometimes called "Barbary Ape", but it isn't an ape) springs to mind - they are known for ripping cars apart when they are driven through nature reserves. --Tango (talk) 11:46, 3 April 2010 (UTC)
Squirrels all seem to have bad attitudes, from the way they retreat up a tree, then "yell" at you. StuRat (talk) 11:48, 3 April 2010 (UTC)
If you've ever tried to give a kitty a worming pill you will know just how evil cute kittens can be! [1] --TammyMoet (talk) 12:11, 3 April 2010 (UTC)
Presumably one tries to force the pill down its throat? Not undue grounds for retaliation methinks! Vranak (talk) 15:01, 3 April 2010 (UTC)
Giant pandas are apparently a lot less cuddly than they look. For an extremely scientific take on this, here's a brief scene of one kicking Wolverine's ass. Matt Deres (talk) 12:49, 3 April 2010 (UTC)
Raccoons are considered by some[who?] to be adorable, but they are 'savage' when cornered. That's from a 1970s Encyclopedia Brittanica account I read. Vranak (talk) 14:59, 3 April 2010 (UTC)
Meerkats come to mind. Lovely looking, eviiiiiiiil things. Regards, --—Cyclonenim | Chat  15:46, 3 April 2010 (UTC)
I've heard that even koalas can be rather testy at times. Deor (talk) 16:48, 3 April 2010 (UTC)
Depending on your definition of "cute" the hippopotamus might fit, but they are notorious for being territorial and dangerous. They may look docile, they're considered to be the most dangerous animals in Africa [2]. -- (talk) 18:31, 3 April 2010 (UTC)
The Peach-faced Lovebird is a cute, fluffy little bird with large, soulful eyes, a legendary reputation for affection - and quite often a very short temper, backed up by a powerful bite (for its size). --Kurt Shaped Box (talk) 19:59, 3 April 2010 (UTC)
Captive Chimpanzees are notorious for "going bad". Cute baby chimps grow into terriotorial and mean-tempered adults that can tear your arms off of your body. Bad times. --Jayron32 21:09, 3 April 2010 (UTC)
The Red-fan Parrot (Deroptyus accipitrinus) looks amazing, but has an extreme temper. I heard of someone who walked into its cage and was attacked, and has to get stitches in his hand and lip. --The High Fin Sperm Whale 00:59, 4 April 2010 (UTC)
Cute but...
Oh, and let's not forget our most cute little polar bear. DVdm (talk) 09:21, 4 April 2010 (UTC)
It depends on how you define cute, but don't forget about dolphins and hippopotamuses which can be dangerous at times. And if you don't mind a slightly alarmist and doomsday-ish source: meow. ~AH1(TCU) 22:42, 4 April 2010 (UTC)
Owls [3] (talk) 07:30, 5 April 2010 (UTC)
Based on the above, I'm going to say: Anything wild is called "wild" for a reason. They may not be "bad tempered" or "violent" by nature, but when cornered they are likely to do nasty things (or as nasty as their size and natural strength and weaponry allows) to the person cornering them. Doesn't make them nasty or evil by nature, it just means they've learned that humans are dangerous and should be avoided at all costs. Not an unreasonable position to be honest.
As for domesticated animals, they tend to be naturally more friendly. But that doesn't mean you won't run into individual specimens with mental disorders (small dogs in particular, and certain purebreeds tend to exhibit these; they're more inbred than any backwoods or royal family on the planet). Similarly, just like humans they can be traumatized in one way or another, or just plain neurotic. Rottweilers are naturally very sweet (about as naturally dangerous as a black lab), but because they have powerful jaws and lots of muscle, people train them to be vicious, and their natural build makes them good at it. Some animals aren't intending to be vicious at all, but make mistakes. Lots of herding dogs can be very dangerous around small children; they don't intend to harm them, but the size of a child makes the animal categorize them the same as sheep. Problem is, sheep have wool and thick hides, children don't, so the "harmless" nip of a herding dog trying to "corral" children can cause injuries. And while I love cats, I suspect that even domesticated cats tend to categorize the world into two categories: Things bigger than themselves, and prey/toys. Cats are vicious little buggers, but only to things smaller than themselves. Does that make them "bad tempered" or "violent"? —ShadowRanger (talk|stalk) 16:00, 5 April 2010 (UTC)
Cats seem to have figured out how to survive, but those small dogs that attack anything, regardless of size, sure wouldn't live long in the wild. StuRat (talk) 18:35, 6 April 2010 (UTC)
Grey bamboo lemurs (Hapalemur griseus) are notoriously bad tempered compared to other lemurs on average. (talk) 19:44, 5 April 2010 (UTC)

Electrical power into food in post-holocaust conditions?[edit]

Supposing someone in a small home or underground bunker had an unlimited source of electrical power,for example an atomic or renewable power source. Assuming some catastrophe occurred such as meteorite impact, atomic war or 28 Days Later zombies making going outside hazardous, what crops could be grown inside on racks for lets say 5 years using artificial lighting, hydroponics and total water/waste recycling to sustain a person without nutritional deficiencies? Or would it be practical at all in a small space?[Trevor Loughlin] (talk) 13:18, 3 April 2010 (UTC)

Read Biosphere 2 - an actual attempt to do something exactly like that (hint: It didn't work!). Even with futuristic technology, you'd need some really fancy chemistry. You can (in theory) use power to push chemical reactions 'uphill' to make compounds with enough energy to be useful foods (sugars, etc) - but humans need protein - and that's really complicated stuff to make artificially. So you're back to using energy to grow plants and that requires light, and water and CO2 - plus some more tricky nutrients like calcium - and you'd need a large amount of space - perhaps an acre per person. Light you could provide - water, you could recycle, CO2 you'd get from your own breath. The problem would be keeping everything in balance. Every drop of water would have be reclaimed - not just urine - but also sweat, tears, moisture in your breath. You'd have to carefully reclaim every ounce of unused plant material - all of your dead skin cells - if someone dies, their body has to be recycled. This is a monumentally difficult problem. When you see how badly things went wrong with "Biosphere 2" in much less than 2 years - you'll perhaps understand why this is so tough. The best chance your survivors have is to have a BIG pile of MREs and good water and air recycling - with enough air and water in reserve to cope with the inevitable losses over time. Even then - it's tough. SteveBaker (talk) 13:53, 3 April 2010 (UTC)
(edit conflict with below) Surely you can vent waste gasses to and draw air from the outside (filtering it, of course, for radioactive fallout, etc.) and water from a well (again, with appropriate purification), so that you don't need to be quite as careful with reclamation. It's still hard to grow enough food of course, but you wouldn't suffer the CO2 and O2 problems that biosphere 2 did. I'm not sure what types of crops are best for that type of thing. Presumably some sort of legume and grain for protein, and then some high calorie starchy food (potatoes, maybe?). Like Steve said, getting all the micronutrients would be hard, but it wouldn't be too hard to stockpile multivitamins for people to consume for 10 years or whatever (and takes considerably less space than enough MREs for everyone). Buddy431 (talk) 14:55, 3 April 2010 (UTC)
The failure of Biosphere 2 doesn't really tell you a whole lot. Much more sophisticated systems have been developed since then, and since the purpose is typically for space travel, they've been done in much smaller volumes. Plants can be tiered vertically and supplying them with adequate light isn't a huge problem. With the right mix of plant foods ,protein is not a problem. You said 5 years, so we can neglect recycling dead humans. That's not to say that there aren't daunting technical problems, especially if you want a totally closed system. My semi-informed view is this is totally possible with present day technology, but it is not easily do-it -yourself (although DIYers surprise us all the time). ike9898 (talk) 14:47, 3 April 2010 (UTC)
I'm also curious about what can be done with unlimited power. If you have connected into an outside wall a Super Special Outlet, from whcih you can draw any number of amps over any voltage (you specify the voltage with a separate connected keypad first), for example, you can set the voltage to the voltage of tension wires - our article says: "In electric power transmission engineering, high voltage is usually considered any voltage over approximately 35,000 volts". Obviously you have to be careful if you go from 35,000 volts to, say, 350,000 volts, as that potential difference could just arc across dry air. But say you could design a safe way to have a 10,000,000-watt "connector", and you were able to draw any number of amps over it, let's say you decide to draw 10,000 amps, giving you... 10,000 gigawatts. What could you do with that? Going further, apparently "the Sun pumps about 386 billion million gigawatts into space", so, if you were to have available all that energy (ie "386 thousand million million" or 386,000,000,000,000,000 Gigawatts), what could you do with it? How about, if, through some means (obviously we've long since stopped talking about a single power outlet, but a limitles array of them) you had access to all of the energy not just from one star but from every star, increasing the above number by a factor of 10^24, ie the above number * 1,000,000,000,000,000,000,000,000. If there is something your above 386,000,000,000,000,000 Gigawatts weren't enough for, surely 386,000,000,000,000,000,000,000,000,000,000,000,000,000 Gigawatts would be more than enough. So, in practical terms, what could you do with all that power? For example, could you even make a Star Trek style teleporter, or food replicator? (Recalling that, by any measure, they had access to FAR less than that amount of technology). Could you magically start producing enormous power of calculation, without having to build something special for it? What else interesting could you do? (talk) 14:08, 3 April 2010 (UTC)
That Question's already been discussed, here. 80.1 is indicating a large, but not truly unlimited power source to be used for day to day living and growing crops. Buddy431 (talk) 14:45, 3 April 2010 (UTC)
... and having more than a few kilowatts available would not be an advantage in a small bunker because it would be impossible to get rid of the waste heat inevitable in any use of power. Dbfirs 20:15, 3 April 2010 (UTC)

Recycling symbol?[edit]

This guy? He's the International Tidy Man[1]

I noticed that on one of my things there's no recyling symbol (as arrows), but an iconic man throwing a piece of paper to bin. What does this symbol mean? (talk) 14:31, 3 April 2010 (UTC)

I think that symbol means, 'please don't litter'. ike9898 (talk) 14:48, 3 April 2010 (UTC)
'please don't litter'? Are you sure? (talk) 18:09, 3 April 2010 (UTC)
If it's not "please don't litter" it could be "dispose this item properly." WHat is the item? — Ƶ§œš¹ [aɪm ˈfɹ̠ˤʷɛ̃ɾ̃ˡi] 21:39, 3 April 2010 (UTC)
Cat's food. [4] The top is made of metal, while the rest is plastic, I think. (talk) 22:05, 3 April 2010 (UTC)
I would assume that the manufacturer doesn't believe that the item can be recycled and therefore is prompting you to throw the container away instead of littering. I have no idea why it wouldn't be recyclable though. Dismas|(talk) 00:26, 4 April 2010 (UTC)
That's a pity. My cat eats around 3 a day, so I thought I could put these to the recycling bin. (talk) 10:52, 4 April 2010 (UTC)
If you're talking about the pouches, apparently they're a sort of amalgam of plastic and a metallic substance, which is currently unrecyclable. (This is what I was told by the recycling department of our local UK council, anyway) --TammyMoet (talk) 14:10, 4 April 2010 (UTC)
I think the OP is referring to something like this [5] (yes I appreciate this is dog food but Sheba who evidentally were the cat food equivalent don't exist anymore) or [6] (left not right). I did come across [7] which may be of interest Nil Einne (talk) 15:31, 4 April 2010 (UTC)
Yep, I mean these [8] What is funny, I had bought my cat similar food but of another brand/manufacturer, and found on the bottom of the package this symbol. (talk) 15:43, 4 April 2010 (UTC)

A quick search on Google Images tells me that the sign means "Keep this area litter free", but that it isn't very widely used. Looie496 (talk) 19:08, 4 April 2010 (UTC)

Prob'ly 'cause nobody pays attention to it anyway... (talk) 05:50, 5 April 2010 (UTC)
Keep THIS area? What area? It's a label on item. (talk) 11:27, 6 April 2010 (UTC)

What is this lizard?[edit]

Unidentified lizard
A better view of the head

I caught this lizard in my back yard in Houston, Texas. It could be native or an escaped pet. Can anyone tell me what it is and what we should be feeding it? Tobyc75 (talk) 16:04, 3 April 2010 (UTC)

I vote for the anole lizard, and, in particular, the Carolina anole. Contrary to the name, they are also native to the gulf coastal plain of Texas. The pic here implies that they eat moths, and also warns that they have a painful, but not poisonous, bite: Carolina_anole#Behavior. StuRat (talk) 16:26, 3 April 2010 (UTC)
The first article above contains this text about their diets:
"Anoles thrive on live insects and other invertebrates, with moths and spiders being some of the most commonly consumed prey. Anoles are opportunistic feeders, and may attempt to eat any attractive meal that is small enough. The primary foods for captive anoles are small feeder crickets that can be purchased at most pet stores."
StuRat (talk) 16:42, 3 April 2010 (UTC)
I'll second that. I live in North Carolina, and I usually have several of these guys roaming my yard on any given summer day. They will change their skin color from green to brown, which can be fun to see. But year, that's an Anole. They're endemic to all parts of the American south. It's probably not an escaped pet, its probably just around. --Jayron32 21:07, 3 April 2010 (UTC)

Cheese Bacteria Manufacturers[edit]

Does anybody know where I could find information about the companies that produce the lactic acid bacteria used to make cheese?-- (talk) 16:06, 3 April 2010 (UTC)

What kind of information? If you're just looking for sources of bacterial cultures, a simple Google search for cheesemaking supplies will guide you to a great number of suppliers. Deor (talk) 16:41, 3 April 2010 (UTC)

I'm sorry, I should have been more specific. I am looking to learn about the large scale wholesale distributors.-- (talk) 16:51, 3 April 2010 (UTC)

I'm still not sure exactly what sort of information about these companies you're looking for. A list of some such firms, linked to their Web sites, can be found here. Deor (talk) 18:30, 3 April 2010 (UTC)

That's a good starting point for me. Thanks.-- (talk) 18:40, 3 April 2010 (UTC)


is it ok to lay a fridge on its side? —Preceding unsigned comment added by (talk) 21:21, 3 April 2010 (UTC)

Yes, for transport. But make sure to let the fridge rest in an fully upright position for at least three(?) hours before plugging it in again. At least old fridges have a nasty habit of catching fire if you start it up (plug it in) again too soon after it has been tilted!
--Seren-dipper (talk) 22:23, 3 April 2010 (UTC)
What would make an old fridge start on fire after having been on its side?! Dismas|(talk) 00:21, 4 April 2010 (UTC)
I would imagine that having the coolant in the wrong place is the problem. StuRat (talk) 01:31, 4 April 2010 (UTC)
No, not quite, it has nothing to do with the freon. The compressor is full of lubricating oil. It is very viscous, and if you put the 'fridge in the wrong position, it will not lubricate some parts of the motor, and it will overheat, just as if you ran a car engine without oil. --hacky (talk) 04:28, 4 April 2010 (UTC)
Anecdotally, an old refrigerator that has been transported on its side and then turned upright and turned on may fail quickly because of metal filings from wear which have not had time to migrate back down to the lowest point. It is folk wisdom I have heard for years, and an old refrigerator I sold to someone failed when they got it home, stood it upright and immediately turned it on. When I have moved an old refrigerator or freezer, I have given it a few hours before turning it on. I have not taken this precaution with new ones. It would be good to check the installation instructions and see if there is any caution regarding new ones. See also [9] regarding the oil issue with laying it on its side. Edison (talk) 19:45, 4 April 2010 (UTC)

Cinnamon causing depression?[edit]

I've begun to notice that when I eat things containing (what is shown in the list of ingrediants as) cinnamon, I feel depressed later. Or at least painful memories from the past make themselves known. Is there any known reason for this?

Two things which cause this are Twinings Chai tea (I have never had any other brand of chai tea) and mixed spice. They both contain cinnamon. Yes, I have read the cinnamon article, so I already know that a lot of what is described as cinnamon is actually cassia.

You might claim that this was due to the nutmeg, but as far as I know Twining's Chai tea does not contain any nutmeg. Thanks. (talk) 22:38, 3 April 2010 (UTC)

The sense of smell is known to be very evocative in the stimulation of memories and emotions -- much more so than other senses. However, in aromatherapy cinnamon is listed as stimulating, even being listed as a pain reducer and antidepressant [10]. As it is a frequently used spice in desserts such as apple pie, it is also frequently associated with "hearth and home". If you are concerned that cinnamon is making you depressed or bringing up painful memories from the past, I would recommend contacting a qualified mental health specialist. Random people from the internet are not qualified to assist you in medical diagnoses. -- (talk) 00:46, 4 April 2010 (UTC)

Aromatherapy is nonsense and considered by many including myself to be only for fools, cranks, and charlatans. The effects only occur some hours after ingesting the stuff so the smell has got nothing to do with it. (talk) 10:21, 4 April 2010 (UTC)

Cinnamon is only ingested in very small quantities, so if it is true that it contains a compound which induces depression, it must have a high bioavailability, cross the blood-brain barrier very readily and have a very high affinity for wherever it is acting. This seems unlikely; are you sure it isn't a nocebo effect? How long did it take until you pinned the "source of depression" as cinnamon? --Mark PEA (talk) 10:41, 4 April 2010 (UTC)
I agree - Aromatherapy#Efficacy makes it quite clear that only the most tenuous evidence is available in support of what is quite clearly pseudoscience. The people who provide it are charlatans and the people who use it are engaging in wishful thinking. Oh if only we could cure diseases by sitting around smelling nice things instead of all of that complicated science stuff with expensive doctors and complicated chemicals. Well, sorry, but lovely though that sounds, it's just premium-grade bullshit that's up there with perpetual motion and the flat earth theory. SteveBaker (talk) 16:48, 4 April 2010 (UTC)
Well, at least it is premium-grade bullshit. It could be worse. It could be cheap bullshit. Dauto (talk) 18:25, 4 April 2010 (UTC)
Steve, your first link says "The consensus among most medical professionals is that while some aromas have demonstrated effects on mood and relaxation and may have related benefits for patients, there is currently insufficient evidence to support the claims made for aromatherapy". I take this to mean that it can be shown to affect mood and relaxation, but that any claims beyond that are unproven. Since we are talking about mood, your link seems to support the idea of aromas changing mood, not refute it. StuRat (talk) 15:59, 5 April 2010 (UTC)
Basically yes, but some essential oils may function as drugs (my rationalist, James Randi-admiring chemist friend is sure that roman chamomile sends him quickly to sleep), and also perfumes are a popular and uncontroversial way of using essential oils to affect people psychologically. They don't have very specific or reliable results, but if a perfume can make somebody think you're vaguely nice, I can't see why a different smell shouldn't make a person think he is vaguely unhappy. FWIW, though, I have a bottle of cinnamon essential oil which I put on the burner now and again to cheer me up (I only have three oils, and it's my favourite). It usually helps, although last time I did this the whole thing caught fire, which raised my anxiety level somewhat. (talk) 03:00, 5 April 2010 (UTC)

It's always hard to rule out idiosyncratic effects in individual people. There is some evidence that cinnamonium cassia has anti-anxiety effects in high doses (see PMID 17512974), but I didn't see any mention of mood-lowering effects. Looie496 (talk) 19:00, 4 April 2010 (UTC)

Steve et al, while I agree there are very few rigourous scientific studies available confirming the efficacy of aromatherapy, every time you (or someone else) inhales Olbas Oil when you have a cold, you are confirming its use for yourself! --TammyMoet (talk) 19:22, 4 April 2010 (UTC)
Fixed your wikilink. Though I have to say, I've never used Olbas Oil or anything else for a cold, beyond the usual hydration improving stuff like chicken soup and the like. Somehow I seem to get over my colds just as fast as everyone else. —ShadowRanger (talk|stalk) 15:46, 5 April 2010 (UTC)
One other thing to consider is that, since cinnamon is naturally bitter, many people consume it with sugar. This may later lead to a sugar crash, which can affect your mood. StuRat (talk) 16:05, 5 April 2010 (UTC)
.. or it may not: as the article says : "Such a phenomenon has never been scientifically observed". AndrewWTaylor (talk) 17:17, 5 April 2010 (UTC)
Yes, but there is at least a proposed physical mechanism by which this effect may take place, unlike for cinnamon causing depression. StuRat (talk) 17:55, 5 April 2010 (UTC)

Now I think of it, it may lead to disturbed sleep and bad thoughts at night. It cannot be the caffeine since I often drink tea without any problems. (talk) 19:40, 5 April 2010 (UTC)


How do i prolong ejaculation without using drugs? —Preceding unsigned comment added by KENNEDY NEWTON (talkcontribs) 23:14, 3 April 2010 (UTC)

See Wikipedia:Reference desk/Science#Role of the Pudendal Nerve in male sexual function?, above, where TammyMoet alludes to a technique involving pressing on the perineum. I assume you actually mean "delay ejaculation" rather than "prolong" — I don't think there's any technique that prolongs the act of ejaculation. Comet Tuttle (talk) 00:03, 4 April 2010 (UTC)
That link doesn't seem to be working for me. Vranak (talk)
It was just archived. Try: Wikipedia:Reference_desk/Archives/Science/2010_March_30#Role_of_the_Pudendal_Nerve_in_male_sexual_function.3F. That's the permalink. StuRat (talk) 02:45, 4 April 2010 (UTC)

i read somewhere that frogs have an extended orgasm for almost 3 hours- so maybe thats what the OP wants;))) a prolonged ejaculation, jokes apart comet tuttle is absolutely right - while there are medications to prolong the act and delay ejaculation/ prevent the ejaculation reflex - there are no known medications to prolong the actual process of ejaculationFragrantforever 09:53, 4 April 2010 (UTC) —Preceding unsigned comment added by Fragrantforever (talkcontribs)

Has anyone ever tried electrically stimulating this nerve? (Please do not try this without medical supervision)-- (talk) 10:51, 7 April 2010 (UTC)
Of course they have![11] Lucky rats. Looks promising!-- (talk) 10:57, 7 April 2010 (UTC)
I am also wondering if anyone has tried violent mechanical stimulation of the prostate to prolong ejaculatory contractions. I bet someone has but Im not going to look for it. Also, would it not be painfull to keep pumping with no throughput?-- (talk) 11:15, 7 April 2010 (UTC)