Wikipedia:Reference desk/Archives/Science/2011 June 20

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June 20

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Species of bird

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What species of bird is in this picture? http://www.flickr.com/photos/dephisticate/5749045210/in/photostream Thank you--Hoangquan hientrang (talk) 01:06, 20 June 2011 (UTC)[reply]

It is definitely a cuculiform, most certainly a cuculid, although which species I know not. μηδείς (talk) 02:33, 20 June 2011 (UTC)[reply]
This suggests Guira guira. Ghmyrtle (talk) 12:34, 20 June 2011 (UTC)[reply]

Bug ID

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This is it - sorry for the bad focus

I have found a number of green insects on the underside of the strawberry leaves in my garden in Washington, USA. Sorry for the really bad focus, but it's the best I could do. They are often found (as this one was) in the middle of some bubbly slime (ewwww). The eyes appear red or orange. Any help with the ID? Thanks - CT2011 (talk) 03:15, 20 June 2011 (UTC)[reply]

Leaf aphid, maybe? I googled [green bug strawberries]. ←Baseball Bugs What's up, Doc? carrots03:19, 20 June 2011 (UTC)[reply]
Definitely not an aphid which has a much more cylindrical body and finer legs and aphids are not found in a 'bubble bath'. This looks very much like the larva of any one of many species of the so-called froghopper which forms a small pod of foam around itself for protection and is commonly referred to as cuckoo-spit, frog spit, snake spit, spittlebug and so on. Richard Avery (talk) 06:17, 20 June 2011 (UTC)[reply]
It kind of looks like a wingless cicada, but it's too small for that. Plasmic Physics (talk) 06:56, 20 June 2011 (UTC)[reply]
I'd agree with Richard - I think it's a froghopper. --TammyMoet (talk) 12:50, 20 June 2011 (UTC)[reply]
Thank you Richard Avery and TammyMoet for the informed answers - and I'm glad to hear the slime is just a bunch of sap. CT2011 (talk) 16:16, 20 June 2011 (UTC)[reply]

Lab management

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Can anyone recommend some resources related to the organization / implementation of a microbiology project? Working in the lab, especially with multiple people on one bench, it has been difficult coordinating our experiments in a way that allows us to be thoroughly repeatable without being completely bogged down in documentation. Thanks, 68.231.149.156 (talk) 04:20, 20 June 2011 (UTC)[reply]

You're going to have to be a bit more specific about the problem you're hoping to solve. Do you have multiple people on one bench because of space constraints, or is it multiple people working on the same project on different shifts, or intermittently? Or multiple people using the same instruments, each for their own independent projects? Or what?
When you talk about coordinating the experiments to be thoroughly repeatable, do you mean that several people are each doing the same assay independently? Do different people perform different steps of an extended task? Are you generally performing the same assays over and over, or are there relatively few repeats of the same task before moving on to something else?
Are there issues with cross-contamination between assays or projects because of shared reagents, space, or equipment?
Ultimately, you can't avoid documentation if you want multiple people to do the same complex task over and over, reproducibly. Bite the bullet, write the SOP, and create a checklist to be used every time anyone runs through a given protocol. (Make sure there's a checkbox for each step, and a blank to fill in for each required measurement. Ten or fifteen minutes of paperwork feels like being "bogged down in documentation" until it saves you thousands of dollars in reagents and a week of repeating experiments trying to track down where a project went wrong.) TenOfAllTrades(talk) 14:19, 20 June 2011 (UTC)[reply]
Might I suggest a video camera ? You can record the experiment, and state the steps explicitly while performing them, rather than try to remember them and document them later. This should save time and effort. StuRat (talk) 16:20, 20 June 2011 (UTC)[reply]

Effects of bilateral seperation on humans.

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From The Disasters of War by Goya. Do not attempt this experiment at home. Cuddlyable3 (talk) 15:32, 20 June 2011 (UTC)[reply]

If sufficient medical technology was present, what effects would it have on a human to be cute in half bilaterally? For this specific question I'd like to assume the medical technology can keep both seperate halves alive.

Ever since reading about folks who actually had the connective hemisphere nerves severed (with good cause obviously), I have been unable to let it go. So, let me see if i can sum up...We know that half a brain can (at times) still be utilized by a functioning human. What would happen if a bilateral split occured with the two hemispheres undamaged (but seperated by space,) and the person kept alive?

Specificly, would it display systems like sentience, consciousness, awareness, identity...etc. And how would one half interact with the other half? Would one person basically become two seperate people, or... Or I dont know what and Id really like to know. A quick summing up because of the confusing nature: Both seperated sides would need to be kept alive (by medical technology if necessary) and seperate from its 'twin' by space. The two are both alive, but can no longer interact as if they were a single being. Would they be emotionless? Develop seperate personalities? And what would happen to the personal identity of the seperated human, again assuming both sides could be kept alive and posessed one of the hemispheres of the brain. If clarification is needed further, feel free to ask. Its pretty confusing to try and write it all out. 74.128.56.194 (talk) 07:19, 20 June 2011 (UTC)[reply]

Do you want to just split the brain hemispheres apart or cut the entire body in half? I believe you meant just the brain, but please clarify. --Ouro (blah blah) 07:22, 20 June 2011 (UTC)[reply]
No, he means the entire body, as indicated in the lead sentence. You can't split the brain stem, that will cause some problems. Plasmic Physics (talk) 08:17, 20 June 2011 (UTC)[reply]
In that case, it doesn't matter what kind of medical technology is used -- the experiment will be invariably fatal for the subject. 67.169.177.176 (talk) 10:24, 20 June 2011 (UTC)[reply]
On the other hand, splitting the brain hemispheres apart is survivable, and can lead to some interesting psychological consequences. For further information, you might be interested in reading Stanislaus Lem's novel Peace on Earth (what the **** -- no article about this world-famous sci-fi author?!), which describes an astronaut who had received this kind of injury while on a space mission. 67.169.177.176 (talk) 10:30, 20 June 2011 (UTC)[reply]
He's under Stanisław Lem (also redirected from Stanislau Lem). AndrewWTaylor (talk) 10:33, 20 June 2011 (UTC)[reply]
Redirect created. Tevildo (talk) 17:03, 20 June 2011 (UTC)[reply]
I suspect what the OP is getting at is that if it were possible to create two separate, sentient humans from one, then the theory of the individual "soul" goes out the window. The closest thing to this I can think of is the Hensel Twins, except they have individual heads, so they are already two distinct entities. ←Baseball Bugs What's up, Doc? carrots10:49, 20 June 2011 (UTC)[reply]
"I suspect what the OP is getting at is that if it were possible to create two separate, sentient humans from one, then the theory of the individual 'soul' goes out the window." That's right: and since identical twins don't share a soul (one can be evil, after all), despite having been a single person (fertilized egg, the religious definition of commencement of personhood), the concept of soul has been disproved. QED. --188.28.194.120 (talk) 20:44, 20 June 2011 (UTC) p.s. a christian mathematician could save the concept of a soul by laborious machinations: however, it would be at the expense of having any recourse against an early abortion, which would have to become as moral as the use of a condom.[reply]
Twins, especially identical twins, often have kind of a "psychic" connection (or "intuitive", of you prefer) and that's certainly true of the Hensel Twins; they do "share a soul" at least to some extent. However, they each have fully-developed brains, and distinct personalities and identities. Even forgetting splitting the entire body, does a complete split of the brain turn one person into two? ←Baseball Bugs What's up, Doc? carrots22:59, 20 June 2011 (UTC)[reply]
I think an interesting question is whether it is possible to make two people out of one—by any surgical procedure, "people" being defined much as it is defined now—having consciousness and a sense of self. Bus stop (talk) 11:19, 20 June 2011 (UTC)[reply]
Well a person only has 1 heart, and a half a heart will not do to keep a person alive. And how would they share 1 digestive system? Does person A get the stomach and person B get the small intestine? I suppose you could give each person a half length small intestine and that might work, but the stomach is not going to be dividable. Googlemeister (talk) 13:12, 20 June 2011 (UTC)[reply]
If a face transplant is possible then perhaps almost anything is possible. Dividing a stomach and reconstructing the material into two discrete stomachs may be possible. I find this as repugnant as anyone else, but it is just an interesting psychological question—can two people be made out of one? If so, their psychological histories would divide from the time they were separated. The main issue would focus on the brain, probably, as that is thought of as the seat of consciousness and a sense of self. Bus stop (talk) 13:55, 20 June 2011 (UTC)[reply]
This is an important exercise in philosophy, but I would recommend against jumping to conclusions. If a soul can be split, that doesn't mean it doesn't exist; it only argues against a few very rigid dogmas (and those holding them, if sufficiently dogged, can choose to ignore the odd conclusions drawn from them, without facing the possibility of scientific disproof).
Naturally the concept of atman, perhaps the most fundamental and important notion of the soul, is most consistent with a soul that is fungible, capable of being split and joined, existing in grey matter without specific individuality. But one can also consider the development of souls changing in a sort of spiritual development. Certain religions speak of Adam and Eve, created and split by God, living in a perfect paradise, from which all other people are made, sharing in the hopes and faults of their spirits; in a sense, then, all souls can be viewed as being split from a single predecessor. The idea remains mysterious, little affected by the progress of science; yet, with the approaching possibility of actually making and conducting many experiments with implications of this type, it will not be possible to simply ignore or idly guess at the issues. Wnt (talk) 23:03, 20 June 2011 (UTC)[reply]
We have an article on the Split brain syndrome, which is very interesting. There is certainly the interesting question to what extent we in general have two, not one, separate selves or consciousnesses, and in what ways these are and are not integrated into our usual everyday sense of a unified "self." WikiDao 18:38, 20 June 2011 (UTC)[reply]
Split brain shows that some stimuli and cognitive functions reside in different hemispheres of the brain from each other. Split brain syndrome is not split personality syndrome so I don't think SBS is enlightening for separate selves. Googlemeister (talk) 20:14, 20 June 2011 (UTC)[reply]
See also our Dual brain theory article, which, true, does not discuss the implications on sense of "self". That the two hemispheres can operate as two distinct "selves" when surgically separated suggests that they may also do so in some way when normally connected. Where is your sense of self located? One hemisphere alone seems sufficient to have a sense of self, and we have two: why don't we, or even split-brain patients, experience a dual sense of self? How do two separate but interconnected (half-)brains result in our usual everyday unified sense of self? WikiDao 21:34, 20 June 2011 (UTC)[reply]
Googlemeister: the OP has predetermined that the split halves be preserved on life support, indicating that any organs that were split, are replaced with machinery like a (cardiopulmonary bypass). Plasmic Physics (talk) 07:21, 21 June 2011 (UTC)[reply]
What about the catastrophic blood loss inherent in this operation? 67.169.177.176 (talk) 11:06, 21 June 2011 (UTC)[reply]
That and cardiopulminary bypass is not recommended for more then 6 hours though according to our article they are sometimes on it a few hours more then that. Also, it would be most inconvinient for a concious person as if either of your blood lines come out, you are going to bleed to death pretty quick if you don't reconnect. Googlemeister (talk) 13:20, 21 June 2011 (UTC)[reply]

Digital camera trouble

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I've carried my Canon Digital IXUS 70 over 3 to 5 continents, including hikes through Kata Tjuta, up Angels Landing, a hot air balloon ride, cycle tours, and snowboarding in the Alps, usually storing it in an outer pocket for easy reach. After only a couple of years of this excellent treatment, it has developed a problem. Images show a darkish spot in the lower middle of the image. The spot seems to become more diffuse with wide angle focus, and more defined if zoomed in. See below. Does this seem familiar to anyone? Is there something that can be reasonably done to fix this? And is this a science, a computer, or a misc question?

 
Zoomed
 
Wide angle

Thanks! --Stephan Schulz (talk) 08:20, 20 June 2011 (UTC)[reply]

What you are seeing is dust on the lens elements, or on the sensor. Every time you move the lens in and out, air is drawn into the device, like bellows. I presume you have cleaned the front of the lens? If so, there is little that can be done other than trying to blow compressed air into the camera (which might damage it further). If you could disassemble the camera, you could clean the dust out, but on such a small camera, this is not really possible. I would suggest contacting a Canon service centre. If it was my camera, I would take compressed air and try to blow it through the gaps in the lens mechanisms. I can not suggest this to you though, as it could damage the camera. Zzubnik (talk) 09:07, 20 June 2011 (UTC)[reply]
I thought it was something like that. If it's the sensor, shouldn't it be invariant under zooming? There are some screws I might try to take it apart, and I certainly can get a can of compressed air. As it is, the camera is nearly unusable for my purposes, so I cannot lose much. Thanks! --Stephan Schulz (talk) 09:20, 20 June 2011 (UTC)[reply]
On reflection, you are 100% correct. It must be in the elements of the lens. I've taken a few cameras like this apart before, and as you can imagine, it's not always easy to get them back together! I did find the page listed below which shows disassembly of one of these cameras. Good luck, and please let me know how you get on :)

http://www.bomaus.net/index.php?option=com_content&view=article&id=54:canon-ixus-70-lens-error&catid=12:projects&Itemid=29

Zzubnik (talk) —Preceding undated comment added 09:44, 20 June 2011 (UTC).[reply]

It doesn't have to be on a lens element. There's probably a fixed low-pass filter, IR filter, or at least a clear protective layer of material between the lens assembly and the sensor itself. (It's relatively unlikely that there's actually anything right on the sensor chip proper; stuff that we'd say is on the sensor is actually going to be sitting on one of these layers just above.) If you have a little bit of schmutz on one of these protective/filter layers, you can still get the effect shown. At higher zoom factors and at smaller apertures, light rays striking the sensor will be coming in more parallel to one another than when you're shooting wide-angle shots or with wide-open aperture. So a little bit of crud just in front of the sensor will look darker and sharper under high-zoom, small-aperture conditions than it will at low-zoom, large-aperture.
That said, for your purposes it doesn't really matter precisely where in the optical train the crud is located; this isn't a dSLR where you can pop the lens off and (gently!) blow out the interior with air. As some of the other responses have noted, if you're comfortable with taking your camera apart (and running a very real risk of needing to buy a replacement, or seriously degrading the alignment and focus of your optics) then you can try disasssembling it to carefully blow out the dust from the accessible interior surfaces. Note that unless you do this very carefully under very clean conditions, you may end up just moving the dust around, or introducing new and interesting contaminants.
If you contact Canon, they should be able to point you to a service center that can do the cleaning; I'm not sure how the likely price will compare to a replacement camera. If you have a local, trustworthy camera shop you might consider arranging the service through them. While few, if any, shops are going to do anything besides box the camera up and send it to Canon on your behalf, the good ones will have seen the problem before and be able to give you some idea of how likely a successful fix is. TenOfAllTrades(talk) 13:42, 20 June 2011 (UTC)[reply]
Of course one of the biggest risks in taking the lens assembly apart is that you'll just get more dust in there. Even in places where there is not a lot of noticeable dust, the stuff gets everywhere. One trick I learned from applying screen protectors is, if possible, set up your work space in your bathroom and run the shower hot for a few minutes to get condensation in the air. Then wait for it to mostly dissipate before you take the camera apart, that should get rid of most of the dust. It's a good idea to take the towels and stuff out first and also don't wear wool or old clothes which might be dusty, synthetic or new cotton clothes tend to be less dusty. Vespine (talk) 01:24, 21 June 2011 (UTC)[reply]

Septic tank

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how do i design a soak away pit/septic tank on a residential drive way; i need the structural details.remmy ogabi — Preceding unsigned comment added by Morbrasintegratedconcepts (talkcontribs) 11:07, 20 June 2011 (UTC) . I added the title to this question. Cuddlyable3 (talk) 11:20, 20 June 2011 (UTC)[reply]

To start with, a soakaway is completely different from a septic tank. Have you read the articles? Whatever it is you wish to build will be subject to varying local regulations so we cannot supply plans that will satisfy them all. Talk to your local water regulator or a builder.--Shantavira|feed me 12:04, 20 June 2011 (UTC)[reply]
I'm going to assume that you need to dispose of water run-off from your driveway, not toilet waste. For that, perhaps you could dig a trench on either side, parallel to the edge of the driveway, and fill it with gravel. This will allow water to run down and fill the trenches, from which it can then slowly soak into the ground. The gravel is mainly to make it safe, so you don't fall into the trenches or get you car stuck in one, but also prevents the sides of the trench from collapsing. Note that you don't want these trenches close to your house, as then water might soak into the basement, or too close to the driveway, as then the driveway edges might be undermined and collapse. I'm not sure what the proper offsets are, however. StuRat (talk) 16:10, 20 June 2011 (UTC)[reply]
There are those grass paver things you can cover your driveway with- is that what you meant? You can find many of them online through Google. If this is homework for an engineering course, then you need to know the standard assumption for vehicle weight that a driveway has to be constructed for, you have to know which kind of plastic to use and what its strength is, and you have to work out how to design the modules so that they will meet the requirements for driveways. Itsmejudith (talk) 16:28, 20 June 2011 (UTC)[reply]

Laptop on the lap and heating

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If I put my laptop on my lap, will that dissipate heat faster than on a table? (provider that table is colder than my lap and not considering the possibility of burning my skin). Quest09 (talk) 12:05, 20 June 2011 (UTC)[reply]

That depends on the relative thermal conductivities of your lap and the table, as well as on temperature differences. I'm always careful to position my laptop so that air vents are kept clear, and I rely on fan cooling, not conduction to my lap. It is possible to purchase cooling pads (powered from USB) to cool the underside of laptops, but I'm slightly suspicious of the logic in using extra power (and hence generating more heat) to try to reduce heating. You could use a pad of frozen peas from your freezer, taking care to avoid obstructing air vents, but it's not a solution I would particularly recommend. If you have an overheating problem then check that the cooling fan is working efficiently & not obstructed by dust etc. Dbfirs 12:43, 20 June 2011 (UTC)[reply]
These things look good for placing a laptop computer on. The "frozen peas" mention above made me think of this. Bus stop (talk) 13:09, 20 June 2011 (UTC)[reply]
If your lap top is over heating, it might be caused by excess dust in the fan which often can be cleaned with a Gas duster. Dauto (talk) 14:16, 20 June 2011 (UTC)[reply]
I'd be wary of putting a laptop on anything at near-freezing temperatures - you could cause condensation inside the case, and short something out. Instead, make sure the laptop is dust-free, and rely on air cooling. AndyTheGrump (talk) 14:34, 20 June 2011 (UTC)[reply]
Don't take me wrong. I think the pea bag idea is whacky too. But it wont cause any condensation inside the computer, rest assured. Dauto (talk) 16:45, 20 June 2011 (UTC)[reply]
Ironically, your lap is probably about the worst place for your laptop. People do not conduct heat very well, and are also too warm. A chunk of metal or glass underneath it on a table will conduct heat away much better. Alternatively, you might use an external fan, pointed at the hottest spots on the laptop, with it up on blocks to allow air flow underneath. StuRat (talk) 16:02, 20 June 2011 (UTC)[reply]
A lot of manufactures find lousy places to put the fan exhaust ports. A human lap can easily block them depending on the bagginess of the clothing and in some cases, how big the user's legs are. Sir William Matthew Flinders Petrie | Say Shalom! 16:04, 20 June 2011 (UTC)[reply]
Depending on certain details of the OP, there may be other side effects to consider. ;) Wnt (talk) 23:07, 20 June 2011 (UTC)[reply]
Truly dedicated computer geeks won't care. :) ←Baseball Bugs What's up, Doc? carrots01:32, 21 June 2011 (UTC)[reply]
In that they don't use them anyway ? StuRat (talk) 08:05, 21 June 2011 (UTC) [reply]

WLAN signal strength varies, distance the same

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Why does the signal strength of my WLAN get stronger or weaker, even if I am not moving? (I suppose the router is not moving around). Quest09 (talk) 12:17, 20 June 2011 (UTC)[reply]

Many things could cause interference and thus signal loss: other computers, people between you and the router, etc. 88.8.78.155 (talk) 14:36, 20 June 2011 (UTC)[reply]
Also, the "algorithm" that actually shows you the signal strength is just an "estimate" which is calculated using various factors, like signal to noise ratio, which isn't just "absolute signal strength". So it's possible that the displayed strength you are shown changes without any appreciable variance in the actual absolute signal strength. Vespine (talk) 01:00, 21 June 2011 (UTC)[reply]

Why are some hair products for men only?

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Some hair products are advertised as for men only. Just for Men (hair coloring product), minoxidil (for hair loss). They are applied topically. Why can't women use these products? — Preceding unsigned comment added by 173.49.19.207 (talk) 12:37, 20 June 2011 (UTC)[reply]

I suppose woman with a normal hormonal balance do not need minoxidil. The other cases might be just a marketing trick. The cosmetic industry is infamous for its bogus claims.Quest09 (talk) 12:49, 20 June 2011 (UTC)[reply]
"Just for Men" hair coloring is a marketing gimmick. It's not different in any appreciable way from comparable products for women; its manufacturer just wanted to be able to sell hair dye to men. Similarly, minoxidil is used to treat baldness in both men and women. You may be thinking of it as male-only product just because baldness is far common in men than in women. TenOfAllTrades(talk) 13:11, 20 June 2011 (UTC)[reply]
Products containing finasteride, which is teratogenic, should not be used by women of child-bearing age because of a strong risk of birth defects. — Preceding unsigned comment added by 148.177.1.210 (talk) 13:18, 20 June 2011 (UTC)[reply]
Finasteride + minoxidil are medicine (nothing to do with cosmetics). "Just for men" is a cosmetic product (nothing to do with medicine). I do not believe cosmetics could cause any harm (or even have a lasting effect) either in men or woman. You can put the label "Just for men" on everything that you want. 88.8.78.155 (talk) 13:24, 20 June 2011 (UTC)[reply]
You probably didn't mean to suggest this, but just for the record, cosmetics clearly can cause harm and can have lasting effects (lead-based Kohl, for example). If you have concerns about using these products, read the small print and check with a medical professional. 130.88.134.136 (talk) 14:25, 20 June 2011 (UTC)[reply]
Do they even use kohl anymore? I thought it was phased out a long time ago. 67.169.177.176 (talk) 21:10, 20 June 2011 (UTC)[reply]
OK, I reformulate: cosmetics are developed with the intention of not having any effect (thus not going thru any mandatory FDA expensive and long approval process). 88.8.78.155 (talk) 14:35, 20 June 2011 (UTC)[reply]
Men's hair needs tough strong stuff for all the tough things it gets up to in the day like playing football in the bar and getting that job, women's hair needs soft and gentle things to help it raise the children, have orgasms in waterfalls, and wander through meadows picking wild flowers. DuncanHill (talk) 14:28, 20 June 2011 (UTC)[reply]
Men's hair has to reflect the reality of surviving on foreign planets, while women's hair only has to reflect moonlight. Bus stop (talk) 15:25, 20 June 2011 (UTC)[reply]
While the same hair dye could work for both men and women, there are some differences which justify different product lines:
1) Women demand more color options.
2) Women have more tolerance for spending long periods of time with foul-smelling chemicals on their heads.
3) Men sometimes have facial hair which they would like to dye dark colors (if women have facial hair, they usually want to remove it or bleach it). A different technique is needed for dying facial hair, using a brush to apply it, instead of a squeeze bottle.
4) Women often have more hair, so need more dye per application.
So, it's not purely marketing, there are legit reasons to have two separate product lines. StuRat (talk) 15:42, 20 June 2011 (UTC)[reply]

i SWEAR BY gRECIAN pLUS fOAM. yOU JUST USE IT LIKE MOUSSE. lEAVES IN A LITTLE GREY, VERY SIMPLE, BUT NOT THE LOOK MOST WOMAN WANT. — Preceding unsigned comment added by 71.251.129.30 (talk) 20:49, 20 June 2011 (UTC)[reply]

Yes, but I've heard it causes damage to that part of the brain which controls the use of the CAPS LOCK key. StuRat (talk) 08:02, 21 June 2011 (UTC) [reply]
Well, Grecian Formula does contain heavy metals (Lead in the US, Bismuth in Canada and Europe). While probably safe "when used as directed" by men, I imagine they may have a harder time passing approval if it was marketed to reproductive-age women. - 174.31.219.218 (talk) 16:16, 21 June 2011 (UTC)[reply]
Lead#Health_effects says that lead poisoning generally occurs either by ingestion or by inhalation of lead dust, and that skin absorption of lead is negligible. So cosmetics that contain lead are not a health hazard when used as directed, either for men or for women. 67.169.177.176 (talk) 20:19, 21 June 2011 (UTC)[reply]
Its just marketing product differentiation. I.e. it gets people to buy more stuff. 2.97.218.142 (talk) 10:18, 23 June 2011 (UTC)[reply]

Blue whiting glowing in the dark

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I have observed that Blue whiting's fishbones (and some flesh), glows in the dark. Why is it like that? Does that happen with many fish?88.8.78.155 (talk) 13:06, 20 June 2011 (UTC)[reply]

This sounds like a type of bioluminescence. Normally, bioluminescence i sa type of chemiluminescence, that it it is caused by a chemical reaction, normally between a pair of enzymes which when they interact, produce the light. In a long dead (and presumably cooked) fish, such enzymes are likely deactivated, and what you describe (glowing in the dark) sounds more like a type of fluorescence or phosphorescence, though the distinction between the two is largely quantum mechanical in nature, phosphorescence generally persists a lot longer, so it is usually the source of something "glowing in the dark". As for what the phosphorescente substance is in blue whiting, I'm not sure, but hopefully those links will give you some background reading on related phenomena. --Jayron32 14:20, 20 June 2011 (UTC)[reply]
The fishbones were not cooked. In the mean time, I think maybe it was not the fish, but some bacteria in the fish which were glowing. I'll check the next time I buy fish - of this or other type. 88.8.78.155 (talk) 14:26, 20 June 2011 (UTC)[reply]
Bones do contain phosphorus, so perhaps some form of that is causing the phosphorescence. StuRat (talk) 15:52, 20 June 2011 (UTC)[reply]
To clarify, bones contain calcium phosphate, not elemental phosphorus. 67.169.177.176 (talk) 21:12, 20 June 2011 (UTC)[reply]

Strange Fish

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Opsanus tau, probably not the fish in question

What is this strange fish caught in a crab trap in the Hudson River? https://picasaweb.google.com/100877348058812847095/Piermont#5620005527927467298 Sesquepedalia 14:39, 20 June 2011 (UTC) — Preceding unsigned comment added by Sesquepedalia (talkcontribs)

Why in God's name are you fishing in the Hudson? That question asked, I am not sure what it is, and I'm a pretty avid fisher. Sir William Matthew Flinders Petrie | Say Shalom! 15:38, 20 June 2011 (UTC)[reply]
Some kind of monkfish? Wrong shape for a flounder which do live there. 75.41.110.200 (talk) 16:26, 20 June 2011 (UTC)[reply]
The caption says oyster cracker which is another name for the Oyster toadfish but our pictures of that fish look much uglier. 75.41.110.200 (talk) 16:29, 20 June 2011 (UTC)[reply]
Actually, the caption says "oyster crusher", not "cracker", and the fish is not Opsanus tau (pictured) which I think looks prettier, not uglier, but is probably in the same toadfish family.μηδείς (talk) 20:44, 20 June 2011 (UTC)[reply]
Sorry, oyster cracker/oyster crusher were listed as alternate names on another website. Oyster crusher is also the name of an unrelated animal, the Port Jackson Shark. 75.41.110.200 (talk) 21:23, 20 June 2011 (UTC)[reply]
It looks like the Gulf Toadfish shown on this Florida Museum of Natural History page - scroll down to the second fish picture. Ryan Paddy (talk) 03:28, 24 June 2011 (UTC)[reply]

typhoons in Russia

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All typhoon tracks from 1980-2005; none hit Kamchatka.

How frequently do typhoons hit the Kamchatka peninsula? Googlemeister (talk) 16:39, 20 June 2011 (UTC)[reply]

Very rarely. A few have gotten close in the past 30 years, but as you can see in the image at right, even those were quite weak. It seems like it may have been hit in 1954 and 1955, but there is very little information available (not surprising from before the end of the Cold War).-RunningOnBrains(talk) 17:03, 20 June 2011 (UTC)[reply]
Ooh! A Jackson Pollock! {The poster formerly known as 87.81.230.195} 90.201.110.44 (talk) 17:59, 20 June 2011 (UTC)[reply]
Typhoons "feed" off of warm water. Without it, they loose their energy and fade away (which is why they never go far inland). The Kamchatka peninsula isn't exactly known for warm, tropical water, so typhoons have to use the energy they have already gathered up to get that far north, which usually isn't sufficient unless you have a really warm summer and a really large typhoon. --T H F S W (T · C · E) 19:23, 20 June 2011 (UTC)[reply]
I understand that, but then Nova Scotia isn't known for that either and it gets hit by a hurricane every now and again. Googlemeister (talk) 20:04, 20 June 2011 (UTC)[reply]
It should be noted that the diagram above does show a few storms tracking over Russia, if not Kamchatka specifically. Several seem to track over, or close to, Primorsky Krai and at least 3-4 appear to make a direct hit on Vladivostok. --Jayron32 19:53, 20 June 2011 (UTC)[reply]
And I think Nova Scotia is closer to tropical regions than the Kamchatka peninsula. --T H F S W (T · C · E) 23:41, 20 June 2011 (UTC)[reply]
It's clearly not impossible; as I said, from maps it appears that it was hit twice in the 50s. Hurricane Faith in the Atlantic was a hurricane as far as 62 degrees north, and the southern end of Kamchatka is only 51 North. It's not a common event, but it can happen.-RunningOnBrains(talk) 00:29, 21 June 2011 (UTC)[reply]

Reynolds number for different constrictions

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Constriction at the end of a tube

Hello, I'm interested in calculating the Reynolds number for constrictions of different sizes and shapes but all similar to that in the diagram to the side. Since I don't have any background in physics, I'm having a difficult time understanding the equations in the WP article. I'm basically after an equation in which I can plug in variables for different constrictions. The constrictions are either hollow circular, elliptical, or rectangular prisms. The fluid is air, which has a kinematic viscosity of about 0.15 cm2/s according to one of my sources. As I've certainly given too little information about this to completely solve my problem, perhaps you could ask me what else you need to know to make feasible a general equation for different constrictions. I really appreciate the help.--el Aprel (facta-facienda) 21:15, 20 June 2011 (UTC)[reply]

The flow before and after the constriction will have different Reynolds numbers given by the first equation in the article you linked. Dauto (talk) 02:00, 21 June 2011 (UTC)[reply]

Is there any article that lists seeds and required kinds of dormancy breaking? I only found Seed dormancy and Wikipedia:NOTHOWTO. 5BYv8cUJ (talk) 21:28, 20 June 2011 (UTC)[reply]

Scarification and the other terms given at Seed#Inducing_germination may be useful search terms to find this information on the internet. E.g. http://www.google.co.uk/#&q=scarification+seeds 2.97.210.205 (talk) 11:58, 21 June 2011 (UTC)[reply]
Thank you for your help. 5BYv8cUJ (talk) 18:17, 21 June 2011 (UTC)[reply]
I've found Scarification (botany) but it dosnt tell you much. 92.29.113.106 (talk) 23:05, 21 June 2011 (UTC)[reply]

I take it then that the answer to my original question is "NO" and "BECAUSE". No, there is no article that lists different kind of seeds together with their required kind of dormancy breaking, because (people here are afraid that) this could violate Wikipedia:NOTHOWTO. 5BYv8cUJ (talk) 18:17, 21 June 2011 (UTC)[reply]

It might also be because, assuming it wouldn't be wikiheresy, no one who has the necessary knowledge and interest has yet been moved to compile the data and write an article. {The poster formerly known as 87.81.230.195} 90.201.110.203 (talk) 18:52, 21 June 2011 (UTC)[reply]
And even more so if doing that would result in the work being censored removed because of pre-emptive fear for wikeipedian wrongdoing. 5BYv8cUJ (talk) 19:18, 21 June 2011 (UTC)[reply]