Wikipedia:Reference desk/Archives/Science/2009 July 7

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July 7

Swine flu

What is the approximate diameter of the 2009 flu pandemic virus responsible for the current outbreak? In μm, please. ~AH1^(TCU) 00:40, 7 July 2009 (UTC)

80-120 nanometres, according to influenza (all strains are about the same size). --Tango (talk) 01:54, 7 July 2009 (UTC)

...which is 0.08–0.12 μm, ;) -- Flyguy649 ^talk 02:21, 7 July 2009 (UTC)

What would be the efficiency of a facial mask designed to be 95% effective in filtering particles that are 0.3 μm in size? Would the clustering of viruses with each other affect this efficiency? ~AH1^(TCU) 13:42, 7 July 2009 (UTC)

Most influenza viruses are transmitted in small droplets, not by themselves, so the mask will offer some protection though I can not give a %. 65.121.141.34 (talk) 14:25, 7 July 2009 (UTC)

Page 9 of this pdf, produced by the NHS (the UK health service), says: "[T]he available scientific evidence shows that these basic face masks don’t protect people from becoming infected." The NHS recommends good basic hygiene (catch coughs and sneezes in a tissue, bin the tissue and wash your hands) as being far more effective (see that pdf for details). --Tango (talk) 15:20, 7 July 2009 (UTC)

When someone sneezes or coughs, do they emit individual virus particles, or are the virus particles part of a much larger droplet of fluid? Edison (talk) 15:27, 8 July 2009 (UTC)

They are within droplets of fluid. As for the masks, I've always been of the opinion that the chief function they serve is to constantly remind you not to play with your nose and mouth (without washing your paws first, anyway). Matt Deres (talk) 02:45, 11 July 2009 (UTC)

Solar cell from calculator harnessing

Can one create a decent solar panel out of the solar cells found in solar powered calculator? If yes, how many do I need and how should I stick them together. The resulting solar cell aggregate should at least power a small electric fan or light bulb. Just curious.--Lenticel ^(talk) 01:03, 7 July 2009 (UTC)

Since each photovoltaic cell from a calculator only creates a small voltage at a small current, you must connect them in parallel to increase the current, and connect these units in series to get the required voltage. If you take a photovoltaic unit out of a calculator, you can use a multimeter to determine its output characteristics in sunlight. You can use a battery and a rheostat to determine the minimum current and voltage needed by your chosen load. An LED light would be a better choice than an incandescent bulb (like a regular flashlight bulb) to be powered by an array of such photocells. Edison (talk) 01:52, 7 July 2009 (UTC)

Thanks. I just thought just now how "ungreen" this would be since you'll be discarding a lot of useful electronic gadgets for something that can only power a small appliance/light.--Lenticel ^(talk) 02:36, 7 July 2009 (UTC)

You can buy photocells at your local RadioShack or other electronics hobbyist store; or at any internet electronic component distributor. This way you don't have to destroy calculators to power your hobby-projects. Nimur (talk) 14:44, 8 July 2009 (UTC)

assessing potential fish stock / resources in a region

how does on assess the existing marine resources, especially fish stocks in a particular region, given the scenario that the stocks are declining due to myriad of reason; especially fishing pressure? —Preceding unsigned comment added by Seacucumber06 (talk • contribs) 06:06, 7 July 2009 (UTC)

• this article about the North Sea cod might be helpful.--Lenticel ^(talk) 06:21, 7 July 2009 (UTC)

fish catch effort

what does the term "catch per unit effort" and "efficiency of the unit" mean in terms of fishing operations? —Preceding unsigned comment added by Seacucumber06 (talk • contribs) 06:28, 7 July 2009 (UTC)

These sound like handwavey approximations for qualitatively comparing different fishing operations (e.g. if it takes more effort to catch salmon than halibut, there is a better halibut catch per unit effort, even if more tons of salmon are bought). The Manual of Methods for Fish Stock Assessment from the Food and Agriculture Organization of the United Nations talks extensively about both terms, but does not appear to define "effort" - my guess is one "unit" of effort could be considered one boat on location for one day, or some similar unit of fishing effort. The source even mentions that a biologist and an economist will differ on definition of "effort" exerted by the fishing crew. Nimur (talk) 15:55, 7 July 2009 (UTC)

I am not a commercial fisherman, but it sounds to me like these are ways of quantifying the efficiency of a fishing vessel. "Catch per unit effort" would be the amount of fish caught divided by the "effort" that was taken to catch them. "Effort" is probably measured in time or, more abstractly, money that was spent on the ship rental, crew, and gasoline. The "catch per unit effort" number would be high if the ship catches a lot of fish with little cost. The importance of the number is that a more efficient ship will earn more money over time. (Aside: There are 1.3 million mechanized fishing boats out there. We're doomed.) Tempshill (talk) 16:00, 7 July 2009 (UTC)

Coriolis effect

I read the first few lines of the article but I cannot understand how it would effect sniping or long range shooting of unguided weapons. So how does the Coriolis effect effect sniping etc.?--116.71.62.75 (talk) 07:34, 7 July 2009 (UTC)

The Coriolis effect is a fairly simple concept. Any object which is moving through the air, and thus is no longer in contact with the solid earth, is only carried forward by its own momentum. The Earth underneath the object is not stationary, however, it is moving along at a good clip, roughly 1,000 miles (1,600 km) per hour at the equator and slower the farther you get from the equator, down to motionless at the poles. Since a flying object is not in contact with this moving ground, the place that object will land can only be determined considering both the motion of the object, and the motion of the earth, which is somewhat complicated given that, unless the object is projected directly along a line of latitude, the earth's linear speed under the object will be changing as the object changes latitude. This changing speed of the earth under an airborne object is really what is meant by the "Coriolis effect". For a sniper's bullet, the bullet itself moves too quickly over too short a distance for the Coriolis effect to make anything but a trivial change on the flight path of the bullet; wind effects would likely cause more of a problem. For an ballistic missle, however, which is likely flying thousands of miles, one had better consider the motion of the earth if one wants to accurately hit the target. --Jayron32.talk.contribs 11:15, 7 July 2009 (UTC)

This answer may be confusing; the important thing is not that that the Earth is moving, but that it is rotating. The projectile once fired tries to move in a straight line as seen in a non-rotating frame of reference, but this is not a straight line when projected onto the Earth's rotating surface.

For example, say the projectile is fired straight north from the equator. As noted, the Earth's surface is moving eastward at over 1,000 mph, more accurately about 1,040 mph, at that latitude. So the projectile starts with 1,040 mph of eastward motion in addition to its northward motion. Say it reaches a latitude where the Earth's surface is now moving east at only 960 mph. Then the projectile is moving 80 mph faster to the east, and it will seem to have curved to the right in flight. That is the Coriolis effect. It works the same way no matter where on the Earth's surface you start from, but I picked this example because it is an easy one to visualize. --Anonymous, 20:46 UTC, July 7, 2009.

In an earlier discussion of the Coriolis effect, a poster said it resulted from a projectile moving closer to (or farther away from) the earth's axis. Even though the projectile stays above the earth's surface, that applies unless the motion is due East or due West. I find it easiest to think of this by imagining the projectile moving over a rotating disc toward the axis of rotation or away from it. The projectile's motion need not be directly toward (or away from) the axis of rotation as long as there is a component of motion in that direction. —Preceding unsigned comment added by 98.17.38.231 (talk) 22:41, 7 July 2009 (UTC)

The ENIAC computer was originally built to calculate artillery shell trajectories in wartime, specifically for taking this rotational trajectory change into consideration. It wasn't completed in time to be of any use, but was repurposed to crunch numbers for the hydrogen bomb project, and really pushed computer technology forward. — The Hand That Feeds You:^Bite 20:36, 13 July 2009 (UTC)

Remote iris scans

Iris scans can be used to uniquely identify people. The UK government is building up a database of them, one way or another. I can also imagine that they could be used to identify wanted people in other countries. My question is, from how far away could you do an iris scan?

I assume an iris scan could be done from a detailed photo of an iris. Such a photo could in theory be taken with a very powerful telephoto lens on a fixed mount. Perhaps illumination by an infra-red or ultra-violet laser could be used to overcome some problems with nightime or haze. The most difficult problem may be aiming the telephoto at the eye on a moving target, but since even cheap digital cameras can find people's faces for auromatic focusing, and the image could be directed into the telephoto by an automatically movable mirror, then its easy to imagine that a computerised aiming system could be set up to do this.

I'm asking my question because I'm wondering if the UK government is going to start recording peoples identities from remote iris scans as they move around the country in the same way that they do now with automatic recording of car registration plates. 78.149.207.75 (talk) 09:50, 7 July 2009 (UTC)

According to Iris recognition#Disadvantages, such scans work at "a few metres" and claims for up to 10 metres are being made. I'm sure HMG, or elements in it, would love to introduce an ANPR system for irises (sp? - apparently irides. Who knew?), but I think we're a fair few years away from this being possible.

You say "the UK government is building up a database of them, one way or another". Do you have any evidence for this, or is it merely a wild assertion? --Tagishsimon (talk) 10:03, 7 July 2009 (UTC)

It's not a particularly wild assertion. The government has made no secret of the fact that it wants to build a national ID database, with or without ID cards, and there have been fairly undisguised policies to increase the number of people on the DNA database. Iris scans have been something often brought up as being something they would want to include. National Identity Register and Information to be contained on the National Identity Register, for a start, or have a look back through the BBC archives. 89.168.106.72 (talk) 18:59, 7 July 2009 (UTC)

An example of remote iris scanning is here http://www.cl.cam.ac.uk/~jgd1000/afghan.html I guess you could take similar photos from perhaps even kilometres away with the right specialised equipment. Snipers with modern equipment can, I understand, shoot people from one or two kilometres away.

The UK is gathering biometric information for passports, the new ones are now all biometric passports. I thought they did include iris scans, but I expect they will soon include them. I think this information, and that from the proposed UK identity cards is going to be held here: Information to be contained on the National Identity Register Although the article only mentions fingerprints currently, there is nothing to stop iris scans being added, and they are already systematically used in other countries. I do not trust the government to refrain from using a surveleillance technology particularly when it is not being monitored, being brought to account, or even breaking the law. 78.149.207.75 (talk) 10:32, 7 July 2009 (UTC)

Consider Mirrored sunglasses --Digrpat (talk) 13:24, 7 July 2009 (UTC)

Yes - they complement your tinfoil hat quite nicely! SteveBaker (talk) 17:02, 7 July 2009 (UTC)

You don't actually need do do an iris scan to positively identify someone, ear shape is another example of an unique identifier. A host of biometric identifiers can be brought to bear. See http://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article5504534.ece and the ACLU site http://www.youarebeingwatched.us/. Unomi (talk) 16:58, 7 July 2009 (UTC)

Car solenoid(?) question

I drive an ancient and battered peugeot 306, which has few frills. About five minutes after turning the engine off, a noise like a solenoid actuating is heard. What would it be? fwiw, it appears to me to have nothing to do with the radiator fan. It takes a good second or so to make its noise. I'm baffled. --Tagishsimon (talk) 10:17, 7 July 2009 (UTC)

Call these guys. Explain your problem. It will be entertaining for those of us that listen... --Jayron32.talk.contribs 11:01, 7 July 2009 (UTC)

The fan solenoid seems like the most likely explanation - but then you'd hear the fan shutting off too (assuming your fan is actually working!). Another possibility is that the thermostat that controls water flow into the engine block is making a noise as it shuts...although that's not anything I've ever heard (but then I've never owned a Peugeot 306). Another possibility is that as everything cools off (and consequently gets smaller due to no longer having been thermally expanded) some mechanical part is pushing against another - then suddenly slipping. There are too many possibilities to narrow that last one down. SteveBaker (talk) 14:38, 7 July 2009 (UTC)

Why do we have nerves in our teeth?

The cause toothache when exposed, but do they have any function at any other time? Woudln't we be better off without them? --rossb (talk) 11:03, 7 July 2009 (UTC)

Pain causes you to wish to fix the problem causeing the pain. If avoiding tooth pain causes you to take care of your teeth; the nerves are doing their job. --Jayron32.talk.contribs 11:20, 7 July 2009 (UTC)

They are also part of the system that tells you how hard you should chomp down and whether the animal between your teeth is still wiggling or already dead. If the Prey is so strong it will make your teeth hurt it would historically probably have been a good survival strategy to let go of it before it broke your jaws or chipped your teeth. Telling the difference between biting a pebble or a nut comes in the same vein. 71.236.26.74 (talk) 12:47, 7 July 2009 (UTC)

I think you'll find that the nerves in teeth have functions you're not aware of. I expect it helps with mastication, with moving food around in the mouth, with knowing when to swallow particles, and other mechanics of the process. —Anonymous Dissident^Talk 13:05, 7 July 2009 (UTC)

I asked a dentist this once. He said it was an effect of how teeth form, and that the nerve in the tooth has no value.. He explained that the nerve forms first, then forms little loops (one for each tooth) and these nucleate the tooth-forming tissue. This nerve doesn't provide any subsequent benefit - it's different nerves that serve the ligaments and provide the sensation of pressure on the tooth. 87.113.26.43 (talk) 14:17, 7 July 2009 (UTC)

I'm pretty sure your dentist must be wrong. Toothache is pretty debilitating - especially in times before dentists and pain-killers existed - it would cause the victim to be a less effective hunter - to want to avoid eating - and would certainly make mating less likely. So it's hard to believe that evolution would allow these 'useless' nerves to continue to exist if there wasn't a REALLY good reason for them to be needed. Hence, I'm inclined to believe Anonymous Dissident's explanation and to write off your dentist's explanation. He's probably right about how they form - but wrong about the lack of subsequent benefit. SteveBaker (talk) 14:42, 7 July 2009 (UTC)

Don't write off the local dentist just yet. Doctor Spiller's explanation is interesting, and he includes why the nerve tissue is important throughout life, to stimulate production of dentin. As to whether the nerve (as in a neuron) forms first, I'm not so sure on that, it looks like it's actually patterning of mesenchymal cells (which are cells from the neural crest) in the embryo and the development of axons from the actual nerve cell itself matches that patterning, but our tooth development article is tough reading. Why the neuron is connected to a pain centre in the brain is unclear. I suppose it has to be connected to something to survive, and the pain sensation would stimulate production of more dentin to better cushion the tooth? It may be a little of both explanations. It's certainly true that when the nerve gets taken out, the teeth are more likely to fracture, I can tell you that for sure. :( The severe pain of a toothache may just be one of those evolutionary tradeoffs. Acute pain from biting on a rock would be adaptive. Chronic pain from a cavity is much less clear - what possible adaptive value is conveyed to the organism? Franamax (talk) 17:08, 7 July 2009 (UTC)

Well, a severe cavity could develop into an abscess/jaw infection down the line. Untreated, that may kill you. I'd argue that would be a Bad Thing. -- Flyguy649 ^talk 17:23, 7 July 2009 (UTC)

I'm pretty sure that tooth aches were around before any sort of viable treatment options were developed. While cavities are definitely bad, there's no evolutionary pressure if there's nothing people could do about it. Rckrone (talk) 18:33, 7 July 2009 (UTC)

As Rckrone says, that constant dull pain doesn't "teach" you anything - however it would lead you to avoid chewing with that part of the mouth, so might avoid further damage. Abscesses can certainly cause death, so in adaptive terms we're faced with the ugly prospect that dental treatment developed early, i.e. the unbearable pain would lead you to rip a tooth out of your own jaw before it killed you.

Basic body plan is a very fundamental aspect of evolution and development, so selection pressure needs to be large to counter it. According to this Nature (journal) article (email me for a copy), denticle formation is dependent on cells from "neural crest mesenchyme (from the trigeminal neural crest stream", so it seems as though innervation and the very existence of teeth may be inextricably linked. I'd somewhat disagree with Steve Baker that having a toothache would prevent you from having sex. Primates and early humans presumably lived with considerable pain from numerous sources. And in any case, so long as you reproduce before your teeth go bad, the job is done.

Interestingly, tooth pain may have actually been a "forcing" factor in human evolution. Looking at these online sources [1] [2], this may have driven increased processing (and thus nutrient availability) of food. When someone was forced to boil their food to soften it, they may have discovered that it was now better food. And humans surviving to a later age of life would be better able to ensure that their progeny survived. Franamax (talk) 20:24, 7 July 2009 (UTC)

Without nerves in your teeth, you'd be breaking them constantly. If you bit down on a rock, you wouldn't know it until you heard the tooth breaking. Those nerves give you an awareness of the texture of what you're chewing on. Looie496 (talk) 21:34, 7 July 2009 (UTC)

It's the nerves in your gums that tell you that, surely? Vimescarrot (talk) 21:47, 7 July 2009 (UTC)

No, you wouldn't. The sensation of pressure in your teeth comes from different nerve endings, embedded in the ligaments that hold the teeth in. The dendrites of the nerve inside the tooth are embedded in the dental pulpus, which is inside the rigid dentine shell of the tooth. Those wouldn't register anything on ordinary chewing; the pulpus will be disturbed only after you've broken the tooth on a rock. The falsity of your claim is evident to anyone who has had a root canal done; the tooth no longer has a nerve within it, but retains the normal bite sensation nevertheless. 87.113.26.43 (talk) 22:50, 7 July 2009 (UTC)

The hypothesis that abscesses in the teeth would teach people to be careful doesn't seem to have applied to people in Ancient Egypt who seemed to prefer their bread with lots of grit from grinding. Dmcq (talk) 13:10, 8 July 2009 (UTC)

Intraocular Lens

This website claims that it can permamently change the color of the iris without much damage through a intraocular implant. However, researching people who got this procedure, almost all of them ended up with secondary glaucoma, cataracts and other issues. I read the article Intraocular Implant and it seems that the % of risk is very low. Am I reading this wrong? --Reticuli88 (talk) 13:05, 7 July 2009 (UTC)

Wikipedia cannot give you medical advice. Also, your Intraocular implant link points to an empty page, so we don't know what article you read (did you mean Intraocular lens, like in the section title?). As far as your research would go, it would probably be good if you looked into sources beyond youtube. Your best bet would be to contact a medical professional that performs these operations, or just your general eye doctor, get a professional consultation, as well as some other more reliable avenues of research. —Akrabbim^talk 16:37, 7 July 2009 (UTC)

Late teens/early twenties

Are there any differences between someone in their late teens and early twenties in terms of physical, mental and emotional maturty? 86.166.47.44 (talk) 14:04, 7 July 2009 (UTC)

Yes - it's fairly well established that parts of the brain relating to self-control are still developing at late as age 18. SteveBaker (talk) 14:31, 7 July 2009 (UTC)

Yeah, people who study this stuff often consider about 25 years a good rule of thumb for having an "adult" brain. Physically, I don't really know. Friday (talk) 14:45, 7 July 2009 (UTC)

Mid-twenties also provides a more mature body. There are many illustrations of this. For example:- Bones are finally fusing: while the body is growing, many of the joins between bones are soft cartilage. This turns to bone once growing is complete (for example, in the skull, ends of the jaw, collar bone etc). (Men's bones fuse later than women's.) Men broaden and put on muscle bulk. Final teeth have come through. Women are physically more suited to child-bearing in the mid to late twenties than they are in their teens. And so forth. As for emotions, the experience of living life matures people. Gwinva (talk) 23:01, 7 July 2009 (UTC)

Apparently (according to Dr Karl's radio show) you can tell when your brain is adult by when you switch to adult sleep patterns (but of course there's such great variety in humans that this won't always be useful) --Polysylabic Pseudonym (talk) 06:44, 8 July 2009 (UTC)

Is this a weevil?

I took this[3] picture this weekend in the Norfolk Botanical Gardens. I think its a Weevil, but either it has no probiscis (if that's what it is) or it is tucked away. I've dug around the weevil & related pages, and haven't seen anything like it. It was found early Saturday morning, sitting on a tall piece of grass, in a field. Keegstr (talk) 14:17, 7 July 2009 (UTC)

Looks more like some kind of borer beetle Anobiidae than some kind of weevil to me. 71.236.26.74 (talk) 14:43, 7 July 2009 (UTC)

By just looking at it I would guess it is a broad-nosed weevil, subfamily Entiminae. However, I am not 100% sure. --Dr Dima (talk) 18:56, 7 July 2009 (UTC)

To be more specific, it could be in Pseudocneorhinus genus or closely related; one of the Entiminae genera clustered around Trachyphloeus. That's my guess. --Dr Dima (talk) 19:05, 7 July 2009 (UTC)

Car engine clapping

To be clear about the reason for this question... I am trying to convince my brother, through email, that he needs to take his car to a mechanic because he cannot diagnose the problem just by listening to the engine while he's driving down the road.

What could cause a 97 Corolla to make a clapping sound while accelerating, very similar to a Harley motorcycle? -- kainaw™ 14:53, 7 July 2009 (UTC)

My first guess would be that the muffler is bad... if it is loose or slightly obstructed. However, if there was a hole or leak, the muffler would sound more "howling" than "clapping". If the sound is definitely coming from the hood, it could be a lot of things - loose valves in the engine block, loose bolts somewhere... how severe is the noise? Nimur (talk) 16:04, 7 July 2009 (UTC)

A related exhaust-system problem, one that older cars often get, is partial failure of the matrix of the catalytic converter. In this, the honecomb elements melt and then resolidify, causing a blockage. This happens repeatedly, and unpredictably, making a changing variety of odd sounds and sometimes leading the engine, which is failing to exhaust spent gas properly, spluttering. The only fix is a new cat. 87.113.26.43 (talk) 20:08, 7 July 2009 (UTC)

It's tough to describe sounds in a way that gets other people to understand them. There's a few broad possibilities here. Is this an exhaust sound, or something else? (Engine sounds will often be things you can duplicate while not moving. This is nice because someone could stand outside the car and listen to it, for example.) Friday (talk) 16:09, 7 July 2009 (UTC)

The first thing in diagnosing any weird car sounds is to ask the following questions:

1. Does it do it when the engine is running but with the car not moving? (This eliminates wheels, axles, brakes, etc)
2. Does the sound get higher in pitch or more frequent when you rev the engine while standing still? (If so, then the noise is being made by some part of the engine rather than some kind of sympathetic vibration).
3. When you are moving, does the sound get higher in pitch or more frequent as the car is moving faster or only as the engine revs change?
4. Does it only happen when you go around corners?
5. Does it only happen when you accelerate?
6. Does it only happen when you brake?
7. Does it only happen at a particular range of speeds? Or perhaps at a particular range of RPM's?
8. Does it depend on the weather?
9. Does it only do it when the engine is cold? Or perhaps only when it's hot?
10. Does turning on and off any accessories (radio, A/C, fans, etc) make a difference?

These questions narrow down the possibilities to something more answerable. SteveBaker (talk) 16:54, 7 July 2009 (UTC)

A pity that Tom and Ray Magliozzi aren't WP editors! Nyttend (talk) 02:14, 8 July 2009 (UTC)

Perhaps - but my advice (above) on how to narrow down what the noise means comes entirely from distilling down thousands of hours of CarTalk advice. SteveBaker (talk) 03:06, 8 July 2009 (UTC)

It's too bad that the WP RefDesk isn't on the radio, we could have endless fun making the poster imitate the noise. APL (talk) 04:01, 8 July 2009 (UTC)

As good as I'm sure that advice is, are you sure that the questioner wasn't more looking for a giant list of possible engine problems to bowl his brother over and convince him to take the car to a mechanic? APL (talk) 04:01, 8 July 2009 (UTC)

Our OP asserts that his/her brother cannot diagnose the problem just by listening to the noise. However, the whole CarTalk thing proves that it is indeed possible to diagnose an awful lot of problems - not just by hearing the noise - but even by having someone humorously impersonate the noise over a crackly phone line while you openly mock them in front of millions of people! There are a large class of car problems that can easily be diagnosed by paying attention to when the noise happens. More than that - if the noise happens when the car is stationary - then right there you can say that this is almost certainly not a dangerous situation - but if it happens only when you turn left or right - then you'd better get your car looked at ASAP because you could easily die as a direct result of delaying another day before you get it looked at! For those reasons alone, I recommend carefully considering the list of questions I posed. Each one of them is designed to eliminate (or reinforce) a particular set of very specific faults. SteveBaker (talk) 04:57, 8 July 2009 (UTC)

"the whole CarTalk thing proves that it is indeed possible to diagnose an awful lot of problems ...\ by having someone humorously impersonate the noise over a crackly phone line while you openly mock them in front of millions of people!" Haha! Well put. APL (talk) 12:50, 8 July 2009 (UTC)

Thanks. I sent all these problems to my brother. He is still 100% positive that it is the catalytic converter and plans to remove it and place a connecting pipe where it used to be. He's stuck in one of those "the guys at the bar said..." mindsets. Apparently, they told him that removing the catalytic converter will also greatly improve his gas mileage and that the only reason we have them on cars is to reduce gas mileage since they have no affect on unleaded gasoline. So, I just have to wait for the "guys at the bar" to be proven wrong yet again. -- kainaw™ 12:56, 8 July 2009 (UTC)

Oh, removing the catalytic converter will improve his mileage. It's also illegal (in most jurisdictions, anyway) and will cause a failure of any emissions test he needs to pass. — Lomn 13:24, 8 July 2009 (UTC)

I agree with Lomn on both points. This is not an acceptable course of action. When he goes in for his annual emissions check (which is mandatory in most states), somebody will notice. Nimur (talk) 14:22, 8 July 2009 (UTC)

The mileage improvement may or may not happen depending on the precise design of the car. Some engines need the back-pressure of the stock exhaust system - others benefit from having a free'er flowing exhaust. Some engine management computers get confused and wave check engine lights at you - on rare occasions causing them to drop into "limp home mode"...hence your mileage might get worse...or perhaps better...or you might find that you car will no longer let you go faster than 30mph! Ditto for horsepower - it's often assumed by 'ricers' that a free'er flowing exhaust buys you 5 horsepower - often, they are deluding themselves. But for sure, there will be considerable additional noise - and that may awake a policeman and that would put you into a world of hurt in some jurisdictions where deliberately circumventing anti-pollution devices can get you into massive amounts of trouble. And absolutely for sure, he'll have to put the cat back when he next has to go for an emissions test. This "fix" really isn't recommended for street cars - and right now, it's not even clear that it would fix the problem because nobody has properly diagnosed that it even IS the exhaust system that's at fault. SteveBaker (talk) 20:35, 8 July 2009 (UTC)

Oh - and kainaw...if you really need to PROVE that your brother is an idiot - read catalytic convertor - the things that the cat does have nothing to do with removing lead:

1. Reduction of nitrogen oxides to nitrogen and oxygen: 2NOx → xO2 + N2
2. Oxidation of carbon monoxide to carbon dioxide: 2CO + O2 → 2CO2
3. Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: CxH2x+2 + 2xO2 → xCO2 + 2xH2O

...all of which are just as important with unleaded gas. Worse still (and the thing that PROVES he's an idiot) is given in Catalytic_convertor#Poisoning which points out that not only do modern cat's not remove lead - but running leaded gas through a catalytic convertor actually destroys the thing. So FAR from them being ineffective with unleaded gas - it's actually the case that they only work at all with unleaded! Tell him "Steve says' you're an idiot." SteveBaker (talk) 20:41, 8 July 2009 (UTC)

Surely you can be diplomatic - tell him "Steve says you know nothing about catalytic converters" or something...? After all, he's family... Nimur (talk) 23:23, 8 July 2009 (UTC)

But that would be a lie! Steve didn't say that. One should not lie to ones' brother. SteveBaker (talk) 00:16, 9 July 2009 (UTC)

And the important thing is not proving him an idiot; it is finding some means to get him to listen to reason instead of drunken idiots. At least this is less harmful to him than the case in which they convinced him that you could quit paying your mortgage and as long as you kept your family dog in the house, the police couldn't evict you. -- kainaw™ 12:49, 9 July 2009 (UTC)

Really? Wow, you learn so much from Wikipedia. Would it work with our tortoise or does it have to be a dog? Also sadly I don't have a mortgage but could I stop paying my electricity bill instead? --BozMo talk 13:05, 9 July 2009 (UTC)

adding to an entry for my employer, a state agency

Hi, I work in the Office of Public Affairs for the California Dept. of Public Health.

In researching the agency I found only a brief wikipedia entry that mentioned the Medical Marijuana Program and a news story about fees for vital records requests. I am in the process of expanding the entry to provide information about the Department and its programs in a very neutral way.

I realize it may appear to be a conflict of interest but I do think expanding the entry would help Wikipedia users learn more about the agency and the services it provides.

Any advice/input from other Wikipedia users is appreciated.

Thank you, Matt Conens [[User:|CDPHOPA]] (talk) 15:31, 7 July 2009 (UTC)

If you want to completely avoid COI, locate references that may be used to expand the article. Post links to those references on the discussion page for the article and ask others to read the references and expand the article. Of course, if you use good references to back what you place in the article, COI should not be an issue. -- kainaw™ 15:35, 7 July 2009 (UTC)

(WP:OR) During our training for dealing with unruly students/residents, we had a presentation by our campus police (who are deputies of the Santa Clara County Sheriff, e.g. "real" police). They also gave us a brief talk about medical marijuana. According to hat discussion, even the police were not sure if medical marijuana is legal or illegal ("on a case-by-case basis"), and so they tend to "avoid" dealing with it unless the quantities involved are very large or some other law is definitely being broken. It seems that California law is so confusing and self-contradictory with regard to this subject that it is hard to make sense of it. When writing your article, bear in mind the legal disclaimer, and definitely stick to reliable sources. Nimur (talk) 16:16, 7 July 2009 (UTC)

Truly - our OP has a clear conflict of interest here. You should simply not edit the article at all. If you feel your department is being misrepresented - or that there are factual errors - or that there is additional information that you have to offer - then please post it to the 'discussion' page associated with the article and let some other editor do the actual work of writing the article. Wikipedia's rules are reasonably tolerant of potential COI - but you really don't want to see news headlines "CDPHOPA caught editing the Wikipedia article about themselves!" - even if it is (strictly) within Wikipedias' rules - it gives a very bad impression. Better to feed information to independent editors - suggest changes WITH REFERENCES - and encourage people who do not have any affiliation to do the actual editing. SteveBaker (talk) 21:21, 7 July 2009 (UTC)

That's by no means a unanimous point of view. We want the articles to be right, and if an article is demonstrably wrong and can be corrected in an uncontroversial way, anybody should feel free to do it (that's my opinion, anyway). Looie496 (talk) 21:28, 7 July 2009 (UTC)

I'm not sure I disagree with you - it's just that the "uncontroversial way" is to place the relevent information (with references) in the Talk: page and let other editors do the editing. Allowing someone with a clear and obvious bias to edit the article is certainly not "uncontroversial". SteveBaker (talk) 03:04, 8 July 2009 (UTC)

Aluminum Garbage cans

Hey all Thinking about making a DIY Smoker http://cruftbox.com/cruft/docs/elecsmoker.html

Should I be afriad of using an aluminum garbage can? Will the heat from the hot plate react with the metal and release some unpleasant toxins into my ribs? —Preceding unsigned comment added by 199.166.14.239 (talk) 15:43, 7 July 2009 (UTC)

There are many aluminum grills. I personally don't use aluminum for grills, pots, pans, utensils, drinking cups, etc... I keep aluminum out of my house as much as possible. But, it isn't considered a health risk by the U.S. government to have an aluminum grill. -- kainaw™ 15:49, 7 July 2009 (UTC)

I believe the concern with aluminum is that it will leach into liquids it's in contact with, which isn't an issue here. People routinely cook stuff over a much higher heat wrapped in aluminum foil. I wouldn't give your trash can aluminum a second thought, and in fact that site has inspired me to build one of my own! --Sean 16:28, 7 July 2009 (UTC)

My main concern would be about how hot the electric hot-plate might get. If it's hot enough to melt plastic insulation parts then it's possible that some piece of live circuitry might come in contact with the trashcan - making a serious electrocution hazard. The hotplate probably won't have been designed to operate in such close confinement without adequate airflow around it - so this is not so far-fetched. I would at least screw a nice chunky bolt to the side of the trash can and connect it up to the ground wire of the wall socket and to the metal case/frame of the hot-plate - that way if something untoward should happen, it'll trip your circuit-breaker. SteveBaker (talk) 16:50, 7 July 2009 (UTC)

The warning "Be sure to file down the edges so that the power cord can't get cut." in the article is inadequate because there is a real danger of electrocution. For safety install a feed-through grommet or similar where the cable passes through the metal wall. A wood plug with a hole for the cable can also be used. The cable should be clamped in some way so the connection to the hotplate is not stressed. Many cables are sheathed in PVC whose melting point is only 100-260 °C. Cuddlyable3 (talk) 20:20, 7 July 2009 (UTC)

Water in the bottom of the can can be a danger. The water might come from leaving the can outdoors in the rain, or condense from steam from damp wood chips or food. Cuddlyable3 (talk) 18:36, 8 July 2009 (UTC)

For what it's worth, my home-built electric smoker uses terra cotta pots rather than metal cans, as they're effective insulators (keeping the heat in the smoker rather than heating everything around). They're cheap, easy to find, and nicely circumvent the problem of potential toxins. (The pot, by the way, is the only design deviation. Get one that's made for plants and it'll even have a nice drain hole in the bottom, perfect for the hot plate's cord) — Lomn 18:59, 7 July 2009 (UTC)

If you can dig out the Good Eats episode where Alton Brown makes his home smoker, he uses this exact set up, and he goes through step-by-step how to build and use a terra-cotta flower pot as a smoker. --Jayron32.talk.contribs 23:19, 7 July 2009 (UTC)

In so far as electrocution is concerned, is the risk mitigated by wrapping the cord in electrical tape? —Preceding unsigned comment added by 199.166.14.239 (talk) 15:11, 9 July 2009 (UTC)

output per man

out put per man per machine formula required [help me] —Preceding unsigned comment added by Sathyavolu sar (talk • contribs) 16:23, 7 July 2009 (UTC)

You have asked this same question before, at least twice. We can't answer it any better unless you provide more information. Nimur (talk) 16:31, 7 July 2009 (UTC)

(This is actually the fourth time the question has been asked here at the ref-desk - plus once more on his/her user page. This user has edited Wikipedia only five times - and each time it's the same question.) We really don't have the first clue what's being asked here. All we're told in various earlier questions is that this is "light industry". But unless we know what these machines are, what the product is - and probably the answers to a whole bunch of other questions - there is no possible way to answer. SteveBaker (talk) 16:44, 7 July 2009 (UTC)

Please write in complete sentences, then we might stand a chance of understanding you. --Tango (talk) 18:04, 7 July 2009 (UTC)

Florida vs tidal wave

How far inland (in miles)could a 80 to 90 ft wave travel along the Florida coast assuming that highest elevations stay between 30 and 40 ft above seal level? Is there some kind of formula for figuring something like this out?209.26.182.3 (talk) 17:47, 7 July 2009 (UTC)

Are thereseals near Florida?Edison (talk) 15:30, 8 July 2009 (UTC)

The Cumbre Vieja article contains numbers for waves "30 to 60 m", for which it says "inundate up to 25 kilometres (16 mi) inland. This would greatly damage or destroy cities along the entire North American eastern seaboard. The physical damage would take tens if not hundreds years to repair and restore. The economies of the countries affected would likewise take several years to return to the pre-inundation levels." That's assuming you mean 90ft (roughly that lower 30m number) as the wave height in the open ocean - when the seafloor forces the wave to surge to much greater heights. Calculating the damage area for a given wave would require a pretty sophisticated fluid-dynamic model of the area, as the wave's energy is spent when interacting with the seafloor, foreshore, and the land, and so the shape and composition of each will be a major factor. Plus the level of tide that pertains when the wave arrives will significantly affect it. 87.113.26.43 (talk) 18:54, 7 July 2009 (UTC)

Your statement that the wave is higher in the open ocean is blatantly false; tsunamis are at their highest near the shore while breaking (see tsunami). You are right though in saying that it would require sophisticated computer modeling; however, it would surely be only a few miles, maybe a few dozen, as the wave's energy is dissipated very quickly. The article cited above states that a 30-60 m open-ocean wave would be a few hundred meters high at impact with the shore, but still only penetrate 25 kilometres (16 mi) inland. For an everyday world analogy, just look at waves over a sand bar; they can start 10 feet high, but be only about 1 foot or less after passing over a sand bar only a few inches above sea level. -RunningOnBrains^{(talk page)} 19:00, 8 July 2009 (UTC)

If we are talking Florida that could still seriously mess things up. Most big cities are near the coast (although depending on what side of the pan-handle the tsunami is going to hit) The bigger problem is that the fresh water (not salt water) supply would be impaired or wiped out and the Everglades might have to be written off entirely. 71.236.26.74 (talk) 09:38, 9 July 2009 (UTC)

I tend to favour the "criticisms" area of the Cumbre Vieja article in any case; other mega-tsunamis have been birthed before and have all failed to cross oceans with the kind of destruction those guys are postulating. It will be no day at the beach (literally!), but some of their figures are right off the chart. Matt Deres (talk) 03:01, 11 July 2009 (UTC)

Depression and violence

Is there any link between the two? I mean, someone who is depressed has the feeling of not being in control of his life, violence could be a way of being in power.--88.1.123.111 (talk) 17:58, 7 July 2009 (UTC)

Depression is sometimes associated with manic-depression, however, even in this case and in the case of other mental illnesses, the sufferes are seldom violent. --Quest09 (talk) 18:09, 7 July 2009 (UTC)

Violence as a result of learned behaviour or as a symptom of extreme emotion can be exhibited by people of all backgrounds and of all mental and physical states. As far as I know, there is no specific link between depression and violence, unless one wishes to speculate that those who are depressed are more likely to be, or have learned to be, violent. I don't see a correlation though. Maedin\^talk 18:24, 7 July 2009 (UTC)

Depression is certainly linked to a higher rate of suicide, which is a form of violence. --Sean 19:52, 7 July 2009 (UTC)

Depression is most commonly associated with passivity but "agitated depression" can sometimes be associated with violence, even of a horrific kind. Looie496 (talk) 21:22, 7 July 2009 (UTC)

I don’t know about depression specifically, but in general, mental illness is a fairly weak predictor of violence. Stronger predictors of violence include being young, being male, having a past history of violence, and substance abuse (alcohol and/or drug). Although not mentioned in my reference, I’ve also read that having been a victim of violence is a stronger predictor of being violent than having a mental illness. The mentally ill who do tend to be violent are typically schizophrenics who are not taking their medication.[4] Red Act (talk) 21:33, 7 July 2009 (UTC)

As a follow-up, here[5] is a reference for being a victim of violence, and witnessing violence also being good predictors of being violent. Note that the correlation between depression and violence is complicated by there also being a correlation between depression and other predictors of being violent, such as having been a victim of sexual or physical abuse, having witnessed violence, or substance abuse by a family member. Red Act (talk) 21:56, 7 July 2009 (UTC)

Yeah, to emphasize the above (I already started writing)—the abstract of this epidemiological study states that they were unable to come up with a causal link leading from mental illness (in general) to violence—but that subjects with mental illness "did report violence more often, largely because they showed other factors associated with violence." It's not an answer to your question, but it does help explain why your question is difficult to answer. There are a great deal of confounding variables involved. For example, a depressive may be more likely to self-medicate with a psychoactive substance that IS related to violence. Or a depressive may owe their mental illness partially to a violent background. Furthermore, clinical depression itself is kind of tricky to define—especially in the milder cases where it can begin to blend into normal behavior. Good studies on the link you're proposing are difficult to construct. Alfonse Stompanato (talk) 22:05, 7 July 2009 (UTC)

In this seminal 1963 paper, Dr. John MacDonald found that people who threaten to perform violence are likely to actually perform violence. This seems to be one of the best predictors. Unfortunately, the sample population for this study was not representative of the larger population, but there are numerous followup studies. Nimur (talk) 14:28, 8 July 2009 (UTC) John MacDonald had a farm, E-I-E-I-O... ;-) 76.21.37.87 (talk) 08:56, 9 July 2009 (UTC)

Human Body Responses

I thought I read somewhere that an experiment was conducted in which women listened to tapes of babies crying and their chest size grew over a period of time. Can anyone point me to a Wiki article about this body response? Also, I think in the same article, it suggested that when men are in close proximity of women, but not seeing them, but smelling "female pheromones", their pupils automatically dilate and that their irises can actually change color. Does anyone know the validity of such claim? --Reticuli88 (talk) 19:43, 7 July 2009 (UTC)

Lactation#Human lactation#Milk ejection reflex can be caused in women by the thought of breastfeeding or the sound of any baby. Cuddlyable3 (talk) 21:19, 7 July 2009 (UTC)

I think the validity of these claims is nonexistent.
The first thing sounds like a fairy tale: I want my breast to grow to feed the baby, so my breast will grow. That is not the way that the growing of breasts, for example during pregnancy, is controlled. This is hormon-based. Another problem with this statement: How long should these "victims" have listened to the crying babies? For weeks? What were the appropriate controls? Did they even have controls (like woman listening to various other sounds for the same time)? Because of these problems I do not believe that such a study was performed in a well-controlled, scientific manner, if it was performed at all.
The existence of human pheromones was never demonstrated under strict experimental conditions, all papers I have seen that show effects have methodological flaws or cannot be reproduced. Next, the human iris cannot spontaneously change color. The color is determined by the structural anatomy of the iris, and this can only change very slowly (in days to months, if you are seriously ill, for example). What can change is the perceived color determined by a subjective observer, depending on the mood and light of a situation. But these would not be parameters that a scientific paper could use, because they are not objective. And the setup you describe is very vague: by "not seeing them", do you mean, they didn't know at all if a woman was nearby? Or was this just being blindfolded, and being touched by a woman? In this situation I would expect their pupils to dilate, because they would get excited, and the reason would not be pheromones :-) Even knowing, without being touched, that someone is coming closer, could lead to a "stress"-response, which also encompasses pupil dilation. --TheMaster17 (talk) 12:25, 8 July 2009 (UTC)

I'm not familiar with any of those claims. The closest I've seen was some original research that crying babies cause even unrelated nursing women to intensely lactate (also, see here). No real surprise there; the effect is a little like your tummy grumbling when you smell something good to eat (only in reverse!). The idea that crying babies could simply make someone's boobs bigger could possibly be related to that phenomena, as breasts do get larger as they engorge with milk. The eye dilation thing reminds me of something I read in Desmond Morris' Manwatching book, to wit: that when presented with a picture of a baby, women's pupils tended to dilate, and so did the pupils of fathers, but not the pupils of childless men. He also discussed other instances of differential pupil dilation, but I don't recall what they were offhand. Matt Deres (talk) 01:34, 9 July 2009 (UTC)

Do cations and anions of a same molecule have different Lewis structures?

I've had to write out the Lewis structure of SiH₄, PH₃ , NH₄⁺ and H₂S. I've just finished the exercise, and I was wondering if the Lewis formula for ammonium would be different if it was an anion (or a neutral molecule) instead of a cation.

Does the electrical charge of a molecule vary its Lewis structure? Thanks to whomever can help. Leptictidium (mt) 19:52, 7 July 2009 (UTC)

It would be. The original molecule is called Ammonia, the other one Amide. For structural formulas see the corresponding pages.--91.6.5.21 (talk) 21:38, 7 July 2009 (UTC)

A good relevant article is Isoelectronicity.

In principle, you could add two electrons to an ammonium cation and get an anion:

NH₄⁺ + 2e⁻ → NH₄⁻

However, doing so would probably cause the molecule to decompose, as the electrons would enter N-H σ* antibonding molecular orbitals and either break two or weaken four N-H bonds.

TO reply more directly; absolutely. The charge on an ion is due to the number of electrons on it. Insofar as changing the charge makes a change to the number of electrons, it would also change the number of "dots" you add to a lewis structure. For a real example of two structures which REALLY EXIST but only differ by charge, consider Sulfur trioxide and the sulfite ion. --Jayron32.talk.contribs 23:16, 7 July 2009 (UTC)

So... in the example I mentioned at the beginning, should I add the extra dot to N or to H₄? Leptictidium (mt) 09:29, 8 July 2009 (UTC)

Here's the Lewis structure of the ammonium cation, NH₄⁺: http://www.benjamin-mills.com/Wikipedia/ammonium-cation-Lewis-structure.png. You want to add an electron to this structure. The usual school chemistry answer is that you can't – nitrogen has a full outer shell of eight electrons and has no room for any more. Likewise, each hydrogen has a full outer shell of two electrons and cannot accept any more.

I read a few papers (such as J. Phys. Chem. A (2004) 108, 727–733, J. Phys. Chem. (1992) 96, 8840–8843 and Faraday Discuss. Chem. Soc. (1981) 71 165-173) and found that the neutral NH₄ radical does exist, as a Rydberg molecule.

I calculated the structures of the NH₄⁺ cation and the NH₄· radical in Spartan (using the MP2 method) and got N-H bond lengths of 1.025 Å for the cation and 1.039 Å for the radical. I also calculated that the extra electron added to NH₄⁺ goes into an electron cloud spread over the whole molecule, that looks a bit like this.

So within the confines of traditional Lewis structures and school-level theories of chemical bonding, you cannot add an electron to NH₄⁺.

But if you insisted on drawing a Lewis structure for the NH₄ molecule (which does exist), it might look a little like this

Ben (talk) 21:27, 8 July 2009 (UTC)

CO2 and carbon taxation

I often see (sometimes grossly) obese people who grunt and pant like a dog that's run 10 miles when they have just walked a few steps.

My question is: do these people create more co2 and use more oxygen than us normal people. If so, should they pay an extra carbon tax? —Preceding unsigned comment added by 79.75.6.187 (talk) 21:55, 7 July 2009 (UTC)

No. They may emit more co2, but they're not introducing new carbon into the ecosystem. It all comes from materials they've eaten.

Compare that to digging up carbon in oil or coal that has been dormant and sealed off since dinosaurs walked the earth. APL (talk) 22:12, 7 July 2009 (UTC)

Yes. Firstly for transportation (be it air, rail, or road) a heavier person requires more energy to move them; if that energy comes from a fossil source, there's more fossil carbon released. Secondly for food; modern industrialised food production makes heavy use of fossil fuels, to plant, fertilise, pest-protect, harvest, transport, and process. The more food one eats, the greater the fossil carbon for which one is responsible. Naturally, while the redacted question presumably discussed the morbidly obese, the same is true for all heavy people, including the freakishly tall and the uncannily dense. In practice, though, do these really amount to a worthwhile amount? And does the extra bother of collecting a new weight-specific tax cost more (in both money and CO2) than it saves? Probably not. Anyway, the morbidly obese die younger (often of sudden, agonising cardiac failure), saving the carbon economy the burden of manufacturing the slippers and warming the cocoa of the selfishly thin. 87.113.26.43 (talk) 22:40, 7 July 2009 (UTC)

Note that the production, transport etc would usually already be taxed if you have a fair carbon tax. Note also a person's size is only likely to be a minor contribution to their carbon footprint. A 200kg person who sits on the couch in their tiny house all day watching some low powered (e.g. 17 inch) LCD TV with no heater or ac and eats crappy food (whatever is cheapest) will likely have a much smaller carbon foot print then someone who drives to gym every day (with their gaz guzzling sports car), and has a very active social life (driving every where of course), watching stuff on their 100 inch plasma when they're at their 1000 square metre home which is always at a perfect temperature; and regularly takes holidays in distant locations and eats only the finest food, e.g. lobster air flown from remote locations with expensive spices that are difficult to collect and again come from remote locations and drinks expensive wines and bottled water. Nil Einne (talk) 00:21, 8 July 2009 (UTC)

I have restored the question. The post comes from somewhat of a known troll, so if the question is removed entirely I won't object. But it's a legitimate question. Poorly parphrasing it and leaving it here to be answered is bad form. APL (talk) 23:39, 7 July 2009 (UTC)

Yes. What a person eats has a major impact on their carbon footprint. According to Livestock's Long Shadow, a United Nations report, the greenhouse gasses due to livestock production in the U.S. amounts to more than that of all transportation in the U.S., combined. An obese person who eats twice as much of everything as if they just ate enough to maintain a healthy body weight is doing more damage to the environment than if they were to double how many miles they drive in a year. Or looking at it from a positive perspective, that same obese person changing to eat just enough to maintain a healthy body weight would have a bigger positive impact on the environment than if they completely gave up their car and just walked everywhere. See also Low carbon diet. Red Act (talk) 02:04, 8 July 2009 (UTC)

What I said above is of course assuming that the person drives an average number of miles in an average car. Red Act (talk) 02:16, 8 July 2009 (UTC)

I should probably have also stated that the hypothetical person was average height, eating an average American diet, and burning an average number of calories when at a healthy weight. And by “environment”, I of course am just referring specifically to global warming. Red Act (talk) 03:09, 8 July 2009 (UTC)

Actually, the reverse is the case. While the person is young and growing, they consume more carbon than they emit...the remainder going to build up the body. As adults, we all consume carbon and emit carbon in roughly equal quantities. But when we die - all of that carbon we stored up in our youth is still inside the corpse. If one were to be cremated - then exactly 100% all of the carbon you consumed and failed to exhale over your lifetime will be turned into CO2 for a zero total carbon impact. But if one were buried - then that carbon is locked away underground. So overall, fatter people who opt to be buried and not cremated have locked away slightly more carbon into the ground than they consumed. Ha! Eat that troll! (Of course, all of this is totally negligable compared to all of the other carbon impact a particular human has on the planet - so the information above is just as useless as the OP's original assertion). SteveBaker (talk) 03:00, 8 July 2009 (UTC)

Steve, surely you know that trolls are silicon-based, not carbon based? 87.81.230.195 (talk) 20:25, 8 July 2009 (UTC)

ovarian follicles

<QUESTION REMOVED>

Sorry, we do NOT give medical advice. Seek professional medical assistance. Exxolon (talk) 22:49, 7 July 2009 (UTC)