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May 30

Adipocere smell

Hello, My question is about Adipocere aka, grave wax.

http://en.wikipedia.org/wiki/Adipocere

A friend of mine sent me a hunk of it, part of a woodchuck that had been trapped in an old well. It was in a zip-lock bag, which sat on a of table of hats and gloves waiting to be put away after a long Alaskan winter.

The smell of the Adipocers seeped out of the zip-lock bag, and stuck to the hat and gloves. It washed out, but how/why can it get though plastic. And stick to anything, including my hands, and some how I could not get the smell of it out of my nose for a long time. Why? Thank you for your time.

Art4u (talk) 02:24, 30 May 2008 (UTC)[reply]

The larger question is why a "friend" would send someone a hunk of dead woodchuck. It seems of little use, other than for pranks I described then thought better of per WP:BEANS and did not post. Serial killers have had similar problems when they leave their victims in the crawlspace of their home. Perhaps you should have covered the plastic bag of dead woodchuck with six feet of earth or a layer of concrete. If you had left it outside during the Alaskan winter, would it have more likely attracted or repelled Grizzly bears when they emerged from hibernation? Crime novels and some forensicsources[1] describe police and pathologists placing a bit of Vicks#VapoRub under theis nostrils when dealing with stinky corpses, and some sources also say it helps with adipocere [2] [3] but we do not offer medical advice. Edison (talk) 03:28, 30 May 2008 (UTC)[reply]

Erm, where's is the medical problem that requires medical advice? I would postulate that the apodocere has a fat based intense odour that produces some sort of particularly persistent and/or adherent molecules that have lodged in the nose and continue to cause the smell. Yes, I realise that individual molecules are required to stimulate the olfactory plate but show me another possibility. With regard to the seeping of odour through a plastic bag this is a well known phenomenon in certain plastics, the actual mechanism of the migration of the smell at molecular level is not known to me. Richard Avery (talk) 07:27, 30 May 2008 (UTC)[reply]

COOLING TOWER EVAPORATION

WHAT IS THE BASIS OF EVAPORATION CALCULATION IN COUNTER FLOW COOLING TOWERS ? WHAT ARE THE UNITS USED FOR LATENT HEAT OF EVAPORATION? —Preceding unsigned comment added by 59.182.38.14 (talk) 03:23, 30 May 2008 (UTC)[reply]

We don't do your homework here. Chris M. (talk) 04:54, 30 May 2008 (UTC)[reply]

Hi. True, we don't do others' homework here, but we can at least help the asker by posting some links to help. Thanks. ~A H 1^(TCU) 17:22, 31 May 2008 (UTC)[reply]

CHEMISTRY

PLEASE EXPLAIN THE INDUSTRIAL PREPARATION OF THE FOLLOWING ORGANIC COMPOUND (a). Ethene (b). Propene —Preceding unsigned comment added by Frankdinero (talk • contribs) 03:30, 30 May 2008 (UTC)[reply]

You might want to check out Ethene and Propene. Paragon12321 (talk) 03:54, 30 May 2008 (UTC)[reply]

Burning stomach fat with an ab machine

I recently saw a commercial for one of those ab machines, the kind that facilitates crunches. Naturally, it included before-and-after pictures of people who lost lots of fat around their stomachs in "just 30 days!"

Of course doing crunches would strengthen and define one's abdominal muscles. But in regard to burning fat in specifically the area around the stomach—does the body burn fat stored in a certain area faster if the muscles around that area are exercised? In other words, say that two identical people each expended a certain amount of energy during workouts, but one did crunches and one did, say, cardio. Would the first person's body burn more fat around the stomach than the second person's, or does the body have its own set order as to which fat deposits it burns? --zenohockey (talk) 04:15, 30 May 2008 (UTC)[reply]

Theres no such thing as spot fat reduction unfortunately. So the only way to get abs is have a really low body fat % (for most people). 61.69.132.119 (talk) 04:55, 30 May 2008 (UTC)[reply]

Well, there is liposuction for "spot fat reduction"...

Atlant (talk) 15:23, 30 May 2008 (UTC)[reply]

Look at this [[4]], particularly at the "Battling the Bulge" section where they describe that walking a mile burns 120 calories. What you can lose in 30 days is water. You also might find this article interesting [5] Crash exercising isn't that great, because you tear your muscles if you subject them to a lot more work all of a sudden. --76.111.32.200 (talk) 00:06, 31 May 2008 (UTC)[reply]

Very interesting...Thanks all. --zenohockey (talk) 01:49, 2 June 2008 (UTC)[reply]

Battery question, part II

Thanks to everyone who answered my question earlier, your comments were very helpful. So (in summary) the main consideration with batteries, in terms of the electronics that use them, is the voltage they produce. And now, operating on this premise, I am going to raise a few eyebrows. What would be the feasibility of using a series of common batteries (e.g., C or AA) to power my laptop? Bare question there, again hypothetical. For reference, the power adapter for my laptop says it gives the laptop 20v at 3.5A and 70W. 63.224.79.202 (talk) 04:24, 30 May 2008 (UTC)[reply]

Possible, but not really feasible. Let's take AAs. It'll take 13 in series to make 20v. The AAs I have sitting around list at just under 3000 mAh, which means those batteries will run that laptop (at peak power) for about an hour. Supposing that the laptop's standard battery lasts 4 hours, that means you need 52 AAs to duplicate its functionality. Those are the single-use ones. Go to rechargeables and the mAh rating drops to about 2000, which means you're looking at about 75 AAs to replace the laptop battery. Larger batteries (say, D cells) will have a higher mAh rating -- about 10000 mAh for rechargeables, or 16000 for single-use. That means you'd only need 13 single-use D-cells instead of the 52 AAs, though Ds cost about 4 times as much (if not more) per battery. — Lomn 05:02, 30 May 2008 (UTC)[reply]

Wow, so it would actually work. How would one hook that up? (Now I'm asking for trouble) 63.224.79.202 (talk) 05:09, 30 May 2008 (UTC)[reply]

Connect them in series, you will also need the same type plug (which plugs into laptop) as for laptops power supply (in worst case it could be connected directly, but it would require disassembly of device). -Yyy (talk) 10:00, 30 May 2008 (UTC)[reply]

NB: Doing this could easily void your warranty - especially if you have to take the laptop apart to get it connected up. While it's a nice theoretical idea, I advise against actually attempting it. --Tango (talk) 12:43, 30 May 2008 (UTC)[reply]

If device is not taken apart, then only problem with this would be undervoltage, when batteries will run out (i am not sure if computers is able to accept reduced voltages from power supply). If power plug is taken from pawer supply, it might void warranty for power supply. This method probably will not be efficient, because laptop computers usually consumes considerable amount of electricity, and batteries are expensive (if you have unlimited access to free batteries, then this is not an issue). -Yyy (talk) 14:53, 30 May 2008 (UTC)[reply]

Also, if batteries are connected in place of original laptop battery, these would need nome sort of smart battery chip emulation (it might be complicated). Laptop batteries usually have lower voltages (11-14V) and this power interface should be able to deal with reduced voltages better (when batteries are running out). -Yyy (talk) 15:01, 30 May 2008 (UTC)[reply]

I'm not sure if I've seen such a device for laptops, but for mobile phones, iPods, and the like, you can definitely buy commercial devices that let you use one-time-use (primary) batteries to power the gadget. And years and years ago, I had a flat-pack external lead-acid battery that connected to the power-inlet jack of my PowerBook 170 laptop computer. That battery was sized to match the outline of the laptop and added (maybe) a 1/4" to the thickness of the laptop, but doubled (+/-) the run-time of the laptop. Another gadget I had for the laptop allowed you to connect an external 9V rectangular-cell battery to the laptop's power-inlet jack. This wasn't enough to operate the laptop, but it allowed the laptop to keep sleeping even while you exchanged the laptop's discharged main battery for a fresh one. (Later, Apple built a small NiCd cell into their laptops to perform the same function: sleeping through a battery change.)

Atlant (talk) 15:14, 30 May 2008 (UTC)[reply]

You can simply take a 4AA battery pack and an USB extension cord, connect the two terminals to the two power cables in the USB cord and charge your iPod off that. The iPod has quite a big tolerance on input voltage so you can charge it with car batteries, lantern batteries etc. as well. --antilived^{T | C | G} 00:00, 31 May 2008 (UTC)[reply]

hens eggs

is it possible to freeze eggsand for how long —Preceding unsigned comment added by 84.48.90.44 (talk) 04:49, 30 May 2008 (UTC)[reply]

if we can freeze human eggs we can freeze chicken eggs i'm sure. now are you talking about fertilized eggs or unfertilized eggs or are you talking about chicken ova for the purpose of later insemination. if the former two, for what purpose, eating or breeding? if its for food yes you can freeze eggs, they just don't taste very well when you thaw them out. i would suggest you only boil them afterwards.` —Preceding unsigned comment added by Myheartinchile (talk • contribs) 06:19, 30 May 2008 (UTC)[reply]

It's probably not possible to freeze them in their shells, but for commercial use, restaurants commonly buy plastic bags containing the frozen, scrambled contents of a hundred eggs. That's the quickest way to crank out omelettes by the dozens. I'd imagine the same process (on a smaller scale) could be done at home. (This has come up on the Reference Desk before, BTW.)

Atlant (talk) 15:06, 30 May 2008 (UTC)[reply]

abreva for genital hsv2 treatment

can you somebody use a product such as abreva to alleviate or quicken the healing of genital (HSV1 not HSV2) fever blisters/cold sores? If not abreva then what? —Preceding unsigned comment added by Myheartinchile (talk • contribs) 06:16, 30 May 2008 (UTC)[reply]

I'm sorry but we can't give medical advice.--Lenticel ^(talk) 09:37, 30 May 2008 (UTC)[reply]

This isn't a medical inquiry, its a research one for my human sexuality class. and also out of curiousity. the articles on abreva and genital herpes didn't answer my question neither did web searches or a call to a health center. —Preceding unsigned comment added by Myheartinchile (talk • contribs) 01:15, 31 May 2008 (UTC)[reply]

Huh? I'm no expert, but "abreva" redirects to Docosanol quote used mainly as an antiviral agent, specifically for treatment of "cold sores" caused by the herpes simplex virus. unquote An here's the wikipedia magic: click on herpes simplex virus and it will get you to an article that starts out with Herpes simplex virus 1 and 2 (HSV-1 and HSV-2) I have no clue what you were looking for, but this seems to cover what you asked about. --76.111.32.200 (talk) 04:04, 31 May 2008 (UTC)[reply]

again does anyone know if abreve is used on the genitals?Myheartinchile (talk) 21:41, 1 June 2008 (UTC)[reply]

chemistry - material science

1.How pH affects the particle size in a chemical reaction ?

2. Explain the properties of Polyethylene glycol (PEG) ?

3.Give the actual definitions of Acid and Base ( Not basing on theories ) ? —Preceding unsigned comment added by Auap (talk • contribs) 06:52, 30 May 2008 (UTC)[reply]

3 media of amplitude can be expressed in keyboards, per Keyboard_expression. Are there any others, and if so, could you list them all?

Also, for all possible, probable and theoretical instruments, can you list and explain all forms of amplitude expression?68.148.164.166 (talk) 08:21, 30 May 2008 (UTC)[reply]

We do not do your homework, we can only point you in the right directions on Wikipedia and, assuming you make an attempt at solving them yourself, help you out where you may be wrong or stuck. Scaller (talk) 09:28, 30 May 2008 (UTC)[reply]

Some weired homework that would be! I think this is genuine.

1) As far as I know it doesn't, How could PH change the size of a particle?

2) See our article Polyethylene glycol

3) I don't know what you want here. What do you mean by "not based on theories"? Theresa Knott | The otter sank 15:56, 30 May 2008 (UTC)[reply]

"An acid (often represented by the generic formula HA [H+A-]) is traditionally considered any chemical compound that, when dissolved in water, gives a solution with a hydrogen ion activity greater than in pure water, i.e. a pH less than 7.0."

"In chemistry, a base is most commonly thought of as a substance that can accept protons. This refers to the Brønsted-Lowry theory of acids and bases. Alternate definitions of bases include electron pair donors (Lewis), as sources of hydroxide anions (Arrhenius) and can be (commonly) thought of as any chemical compound that, when dissolved in water, gives a solution with a pH higher than 7.0. Examples of simple bases are sodium hydroxide and ammonia."

Hope that helps. Regards, CycloneNimrod^Talk? 16:42, 30 May 2008 (UTC)[reply]

An acid can coagulate a colloid, due to the charge changing on the colloidal particles. For example, add acid to milk and it will go thick and lumpy, onthe road to cheese. Graeme Bartlett (talk) 22:35, 30 May 2008 (UTC)[reply]

SPACE

WHY DO OBJECTS GET SMALL WHEN TRAVELING NEAR THE SPEED OF LIGHT IN SPACE 59.88.65.80 (talk) 09:16, 30 May 2008 (UTC)[reply]

Those objects that get smaller are most likely moving away from you. They occupy less and less of your field of vision. Was this a clever troll, meant to inspire the questions of many a confused theoretician not aware of the most logical and sound explanation? I will assume good intent. Scaller (talk) 09:32, 30 May 2008 (UTC)[reply]

I think the question is regarding Length contraction also known as Lorentz contraction. It is for the same reason as time slows down relative to an outside observer in order to maintain the constancy of the speed of light. Jdrewitt (talk) 10:04, 30 May 2008 (UTC)[reply]

(Scaller) Oh, then the impression of decreasing size (versus lengthening, that seems an increase) mislead me. Thank you. :) 81.93.102.185 (talk) 09:44, 31 May 2008 (UTC)[reply]

The core tenet of Special Relativity is that the speed of light will always been measured as constant by any observers (it is invariant), but all other things will be measured relatively based on the reference frame of the observer (they are relative). As a result, when you start doing talking about things which move at or near light speed, the only way for the very large speed of light to be measured as constant by other observers is you start seeing both time and space as being relative, as actually changing. You don't have to see things as getting small at the speed of light; you can see them as occurring at very different times than what the person inside that fast-moving frame would say. The reason why time and space seem relative is due to how we measure both time and space—how we define what length is, what an interval of time is, both are dependent on measurements of the speed of light. Make any sense? --98.217.8.46 (talk) 15:00, 30 May 2008 (UTC)[reply]

There once was a fencer named Fisk

Whose stroke was exceedingly brisk.

So fast was his action

the Fitzgerald contraction

reduced his rapier to a disk.

Atlant (talk) 15:02, 30 May 2008 (UTC)[reply]

Canthaxanthin concentration in Cantharellus cinnabarinus

What is the concentration of canthaxanthin in Cantharellus cinnabarinus (Wikipedia currently doesn't have an article on it, but on the genus Cantharellus)? The answer can probably found in the original paper of the discovery of canthaxanthin, but I don't have fulltext access - maybe some of you have? Thanks in advance! Icek (talk) 11:14, 30 May 2008 (UTC)[reply]

They don't provide a concentration figure. Also, they don't provide a good figure for the amount of canthaxanthin recovered, saying only that they got 0.9 mg, plus "a lesser amount" by recrystallization. They also mention "small amounts" of what they think was an isomer of canthaxanthin. I guess the total amount was in the neighborhood of 1 mg. They started with 75 g of mushrooms, so a rough figure for the concentration would be 13 μg/g. I had no idea that a pigment could color something at such a low concentration, but that shows what I know, I guess. --Milkbreath (talk) 12:13, 30 May 2008 (UTC)[reply]

You can ask for fulltext versions of pretty much anything at the Resource Exchange so you can read it yourself. Hint to Milkbreath, are you signed up there? ;) Franamax (talk) 17:25, 30 May 2008 (UTC)[reply]

Thank you very much, Milkbreath, and thanks for the hint, Franamax! Icek (talk) 14:03, 2 June 2008 (UTC)[reply]

You're welcome, and upon reflection I guess the stuff is mostly in one tissue or another. --Milkbreath (talk) 14:44, 2 June 2008 (UTC)[reply]

animal colouration

why do so many mammals(dog,horses,cats for instance)have a flash of a different colour on their chests?---Jo. Russell —Preceding unsigned comment added by 86.13.210.32 (talk) 12:34, 30 May 2008 (UTC)[reply]

Why questions are always hairy (if you'll excuse the pun :-) Animal colouration gives 3 main uses for color: concealment, signaling and mimicry. Although it may seem odd, a different color spot can actually help hide an animal. On top of your carpet a tabby cat like the one in Camouflage would stand out, but look how well the stripes hide it. So the spot could help "break up the pattern" of the animal. It might also signal that "this is the end with the head". To prey it would be useful to know what end of an predator it's facing and a predator would find it useful to know where an animals neck to bite is. (That would however not serve your own survival, so maybe not a likely scenario) It may also just be attractive to mates. (After all an animal can't just throw on a cool T or sassy skirt, but ^o.o^ have you SEEN the one with that spot?) I can't think of a model for mimicry. Having all those very sensible possible reasons, it's unfortunately just as likely that it's just a bit of gene left over from an ancient ancestor or pure coincidence and doesn't serve any purpose at all. --76.111.32.200 (talk) 21:03, 30 May 2008 (UTC)[reply]

Countershading? --Carnildo (talk) 21:19, 30 May 2008 (UTC)[reply]

Can anyone identify this bird?

http://pets.webshots.com/photo/1101444074041514092KxzdCz Thanks. :) 99.245.92.47 (talk) 12:58, 30 May 2008 (UTC)[reply]

I think this is the Crested Coua (Coua cristata), native to Madagascar. Most of the few images that I can find are greyer than shown in your photograph, but the patch of bare blue skin around the eye and the untidy crest seem to match. Here are a few links: [6] [7] [8] [9]. There is a Blue Coua (Coua caerulea), but it doesn't seem to have much of a crest [10] [11]. Also, the patch of blue skin around the eye doesn't seem quite right in the Blue Coua--Eriastrum (talk) 20:14, 31 May 2008 (UTC)[reply]

Uncontacted Tribes in Brazil

[[12]]

From what I think I understand, no one from the outside contacted these remote tribes but does that also mean that they don't know that another world exists from their jungle homes? --Vincebosma (talk) 13:08, 30 May 2008 (UTC)[reply]

It depends on the context you mean. Take, for example, the ancient Greeks. Eratosthenes estimated the size of the Earth some 2200 years ago. In that sense, the Greeks were quite aware that far more world existed than they had explored. On the other hand, they would not have been able to imagine the details of, for instance, the Maya civilization. Similarly, uncontacted peoples may vary in the degree of knowledge of the rest of the world. — Lomn 13:20, 30 May 2008 (UTC)[reply]

I'd say they would all have some inkling something else is out there, by seeing airplanes passing overhead. They may not figure out that people are on the planes, however. Also, they may have heard by word-of-mouth (from another nearby tribe that has had contact with the outside world). StuRat (talk) 00:03, 1 June 2008 (UTC)[reply]

Well, first off, we dind't know about their world. It's just that 'our' world is bigger. :) But if they have contact with neighbouring peoples (which may be very limited), then, as StuRat says, they will probably have heard of peoples still further away. Including us. But that info is likely to be very distorted. Think of the pictures mediaeval Europeans made of distant peoples. Absolutely weird, some of them, and mostly scary. We 'knew' about them, but not really. And it's likely to be the same with them now. Imagine how their possible perception of us as something weird and scary may have been reinforced when they saw the helicopter hover over their vilage. They must have been scared shitless, and if they could make out the (white?) people inside, they any attempts at overland contact is likely to have become much more risky. DirkvdM (talk) 08:01, 2 June 2008 (UTC)[reply]

Hologram monitors?

Are there any emerging technologies that replace monitors or TV's with holograms? 65.41.95.198 (talk) 13:17, 30 May 2008 (UTC)[reply]

Nothing very promising, no. --98.217.8.46 (talk) 14:50, 30 May 2008 (UTC)[reply]

The bandwidth required for a true "holographic" (volume-filling) display is much, much larger than the bandwidth required for a 2D display. If you need a million pixels for a given 2D display, you'd need a billion voxels for the equivalent space-filling display. We also don't yet have a good, cheap mechanism for creating visible voxels in free space. On the other hand, stereoscopic displays are quite practical today and are often used in scientific applications. Because they only represent the stereoscopic view seen from one point in space, they only require about twice the data as a 2D display.

Atlant (talk) 14:58, 30 May 2008 (UTC)[reply]

The Feb. 7 issue of Nature has a letter on "An updatable holographic three-dimensional display" described in that issue as "a breakthrough". It is a 102-mm square photorefractive polymer that can be rewritten and has a 45-degree horizontal viewing angle, meaning you could walk one-quarter of the way "around" the object. This is the first one ever, and it takes 3 minutes to update the screen, but it's there. I'm not sure if the bandwidth comparison is exactly right, since a holograph encodes the image in a completely different way, but the overview mentions military, medical and video-gamer markets, who are presumably willing to pay for bandwidth. It certainly won't be on the shelves for Christmas though. Franamax (talk) 17:20, 30 May 2008 (UTC)[reply]

Have you read the article on volumetric display? it's not exactly holography but fairly close -russ (talk) 22:33, 30 May 2008 (UTC)[reply]

And it's not terribly promising, at least for commercial usage. I don't think any of the methods mentioned on that page have much promise. --98.217.8.46 (talk) 23:44, 30 May 2008 (UTC)[reply]

Orgasms

I am 17 years old and I have not orgasmed yet... I just had sex for the second time yesterday... And I still can not bring myself to orgasm I masturbate regulary it feels good but I cant bring myself to climax. Even when I cum I don't get that enormous satifactation I hear about from others. What can I do? JenJenAndAway (talk) 13:44, 30 May 2008 (UTC)[reply]

How do you qualify "enormous satisfaction"? It's impossible to know what feeling another person gets from something beyond their expression/descriptions of it. Are your peers over-exaggerating? Are you expecting too much? Generally 'cumming' is a way of describing the act of orgasm (certainly for males), so in the second part it suggests you have already orgasmed before. The obvious options open to you are to experiment and try different ways to get yourself in that state. It sounds more like a mental, rather than physical issue from what you've said. If in doubt then see a doctor/medical professional who may be able to help you further. 194.221.133.226 (talk) 14:06, 30 May 2008 (UTC)[reply]

I suggest you stop worrying about it. If it feels good, your doing it right! Theresa Knott | The otter sank 15:46, 30 May 2008 (UTC)[reply]

We're bordering on medical advice here, really. I'd advise you to visit appropriate professionals for advice. Regards, CycloneNimrod^Talk? 16:38, 30 May 2008 (UTC)[reply]

Get a copy of "Our Bodies, Ourselves" and read it. --BenBurch (talk) 01:12, 1 June 2008 (UTC)[reply]

"... and read it"? Aren't you being a little too demanding? :) DirkvdM (talk) 07:51, 2 June 2008 (UTC)[reply]

This is the Avril troll [13] Nil Einne (talk) 12:21, 2 June 2008 (UTC)[reply]

Seems to be a legitimate question, though. I think it's best to respond to questions here on their own merits, regardless of who asks them. It's certainly easier that way. --Tango (talk) 12:36, 2 June 2008 (UTC)[reply]

Perhaps, but this question doesn't make much sense anyway. While there's a possibility a 17 year old will not realise that particularly for males, 'cumming' is an orgasm/climax, it's rather unlikely IMHO. (There's a big difference between saying I don't seem to get much satisfaction from my orgasm and saying I cummed but didn't orgasm.) This combined with the fact the question seems to be coming from a male, but the name sounds female made the question somewhat suspicious. Now that there's evidence this person is the Avril troll, I personally don't see any point responding to this question since this users repeated bad faith questions make me suspect he or she does not really have a genuine question and so there's a good chance no benefit will come from my answer so I don't see any point wasting my time further on someone who's already wasted enough of my time. Of course, others are free to respond how they see fit, but I think it's worth letting them know who that this comes from a known troll. Nil Einne (talk) 18:49, 2 June 2008 (UTC)[reply]

Jack

Re definition of 'jack' as used in electronics:

Editors: please view the page

http://en.wikipedia.org/wiki/TRS_connector

Suggest that the author/s was/were confused.

A 'jack' is a socket, as in the slang 'up your jack'. Therefore a 'plug' cannot possibly be a jack.

Cheers, bwegz —Preceding unsigned comment added by Bwegz (talk • contribs) 13:53, 30 May 2008 (UTC)[reply]

Can be either plug or socket - see jack (connector). I would assume "jack" by default meant a plug, but that may be a Britishism. Reminds me of the time when we pretended innocent puzzlement and made our physics teacher explain the origin of the terms "male connector" and "female connector" ... "Gosh, sir, isn't that a bit rude ?". Gandalf61 (talk) 14:18, 30 May 2008 (UTC)[reply]

Strangely enough, I've always thought using the word "jack" to refer to to connectors, is an americanism, while the british would prefer the words "plug" or "socket". Astronaut (talk) 15:55, 30 May 2008 (UTC)[reply]

A jack is the socket and a plug is the plug. "Jack" alone has never, to my knowledge, referred to a plug in a reliable source such as a standards guide, a handbook for professionals or a textbook. See [14] from 2006 for phone plug and phone jack. A manufacturer's site [15] shows an adapter with two RCA jacks and one RCA plug. The terms are not interchangeable. Somehow the possible British usage is used in TRS connector with the redundant term "jack plug" to refer to what the references from the article call simply a "plug." It would be interesting to add a historical paragraph showning the development of this redundant terminology in popular British usage. Edison (talk) 18:54, 30 May 2008 (UTC)[reply]

See [16] & [17] & [18] & [19]. From what I can tell, jack means connector or more specifically TRS connector in the UK. It does not generally mean socket so jack jack makes no sense Nil Einne (talk) 05:41, 31 May 2008 (UTC)[reply]

There are some books [20] which use "jack plug" to refer to a plug. Perhaps this was to make it clear they were not referring to a "mains plug." Logically they should call the female part a "jack jack." Older books such as this 1917 one [21] just call them a plug and a jack (referring to 1/4 inch telephone plugs and jacks). Edison (talk) 19:18, 30 May 2008 (UTC)[reply]

Anyone else ever encountered "Jill"? —Preceding unsigned comment added by 76.111.32.200 (talk) 00:08, 31 May 2008 (UTC) Boticide would be sweet--76.111.32.200 (talk) 00:09, 31 May 2008 (UTC)[reply]

According to the OED (2nd ed. 1989), a jack is specifically a socket with one or more pairs of normally closed contacts that open when the plug is inserted, so that the plug becomes part of the circuit (earliest def. 1891). Thus (OR alert) the term 'jack plug' makes sense if you define it as the type of plug that is designed to be inserted into a jack. I also looked on answers.com, which consists mainly if not entirely of US sources, but it also says that a jack is a socket. So I agree with the OP. --Heron (talk) 10:51, 31 May 2008 (UTC)[reply]

It is news to me that 'jack' refers to a socket. I am used to 'jack' and 'jack plug' used interchangeably to mean the male connector described here as TRS connector (a term not only unknown to me but positively misleading, because 'TRS' to me is heat-resistant mains cable). If I needed to refer to the female connector I would say 'jack socket'. I am familiar with the phrase 'phone jack', and now I think of it I recognise that it often means the socket; but I would have taken this to be a transference from what I thought of as the primary meaning of a particular kind of plug.

Since words mean what people use them to mean, I assert that it is simply wrong to say that 'jack' does not mean 'plug', at least in the UK. --ColinFine (talk) 00:05, 1 June 2008 (UTC)[reply]

Ants

I have read somewhere that if ants where scaled up to human size they would collapse under their own weight. Is this true? If so, what forces change over thw dimensions which are so relatively close to each other? Bastard Soap (talk) 14:10, 30 May 2008 (UTC)[reply]

Yes. I think we have an article on this somewhere, but it's simple to explain: if you scale up an ant by a factor r, then it will become r³ times heavier, and its legs will become r² times thicker (in terms of cross-sectional area, which is proportional to load-bearing ability). Thus the stress on the legs will go up by a factor of r, so for r large enough (up to human scale is plenty), they'll break. Algebraist 14:19, 30 May 2008 (UTC)[reply]

The classic text here is On Being the Right Size. Algebraist 14:24, 30 May 2008 (UTC)[reply]

EPISTEMOLOGICAL UNITY:

DOES AN EPISTEMOLOGICAL UNITY AMIDST GRAVITY AND ELECTROMAGNETISM EXIST, OR NOT? —Preceding unsigned comment added by 134.2.3.103 (talk) 15:16, 30 May 2008 (UTC)[reply]

Which answer would be more satisfying to you, "YES" or "NO"? You need to more carefully define epistemology and unity to really enable a meaningful answer here. Nimur (talk) 15:35, 30 May 2008 (UTC)[reply]

Considering epistemology refers to philosophy, perhaps the philosophy desk would be a better place for your question? Had you wanted to know something on a scientific basis, we may have been able to help.

Umm... there isn't one. the Humanities desk, perhaps (as cryptically linked to by Nimur above)? --ColinFine (talk) 00:08, 1 June 2008 (UTC)[reply]

I didn't mean to be cryptic. Sometimes I forget that users do not all have WP:POPUPS installed to allow for quick mouse-over skimming of wiki-links. I'll be more explicit! Nimur (talk) 16:23, 2 June 2008 (UTC)[reply]

Sky color with thicker atmosphere

If the Earth's atmosphere was thicker but of the same composition, what would the sky look like? How much thicker would the atmosphere have to be to make a difference that we could see with the naked eye? 69.111.189.55 (talk) 18:11, 30 May 2008 (UTC)[reply]

Well, I'd say a thinner atmosphere would scatter less light, so would look darker - possibly dark enough to see stars through it. Then, a thicker atmosphere would scatter more light and likely appear brighter and whiter. The extraterrestrial skies article may shed some light too. ~Amatulić (talk) 18:20, 30 May 2008 (UTC)[reply]

It's been a long time since I did any work on simulating atmospheric effects, but I don't believe there would be any major changes. Rayleigh scattering is already strong enough that outer space doesn't contribute much to the color of the sky. The most noticeable change would be that atmospheric bluing of distant objects would get stronger, and be visible on closer objects. Eventually you'd reach a point where the Moon is no longer visible (quick estimate: a 1000-fold increase in atmospheric pressure), but I don't think you'd lose sight of the Sun before the atmosphere got so thick it wouldn't be a gas anymore. --Carnildo (talk) 21:34, 30 May 2008 (UTC)[reply]

I don't agree with the Sun part, as 1000 times more atmosphere would presumably mean 1000 times more and/or thicker clouds. Thick storm clouds can block out the Sun as is, but at 1000 times the normal density even light fluffy clouds would blot out the Sun. StuRat (talk) 23:55, 31 May 2008 (UTC)[reply]

That would depend on whether or not you increase the amount of water when you increase the pressure. It's a common problem with this kind of question - when you change one thing, you have to think carefully about what else you change and what you keep fixed. --Tango (talk) 00:30, 1 June 2008 (UTC)[reply]

ladybug diseases and breeds

I live in Topeka, Kansas at 39° N 95° W. We have had three dry summers in a row. Last summer I noticed none of the lady bugs had very good spots. Our local ladybugs have always been a bittersweet color, not bright red, and that has not changed. Very suddenly it became difficult to find a ladybug with spots. The ones that do have spots are "faded". It's like the spot disintegrated. The black is still a true black but the spots have become sort of granular, like the way a newspaper makes gray with black ink on white paper. In addition the ladybugs seem slow, they don't fly as often and they don't even discharge their poison very readily. My question is, could this be a disease like the colony collapse virus in bees, or is it an invasion of a slow and spotless species?

99.10.73.248 (talk) 20:11, 30 May 2008 (UTC)[reply]

To me, this sounds more like natural selection due to environmental pressures than diseases. According to the ladybug article, there are hundreds of species, presumably all with different combinations of colorations and spots. Because of the short breeding times, it is quite possible that environmental changes have, over successive generations, caused a different population of species to become more common than what you were observing a few years ago. Or the dominant species in your area have adapted to the new environment, and a consequence of this adaptation may include a different coloration. ~Amatulić (talk) 20:26, 30 May 2008 (UTC)[reply]

worm farms

I'm thinking of getting a worm farm, but I'm concerned about issues like smelliness. I've looked at the article, and indeed odours are a potential hazard, so can anyone tell me from theory or experience if this is a major problem, or if it is easy to avoid? I live in a block of flats, and my gardening ventures have turned out poorly, like if I try to preserve a plant, it soon turns into compost, so I'm not sure how I'll go at maintaining compost itself. The indicators are that I have no skill whatsoever at this kind of thing, so I need it to be easy. thanks, 203.221.127.63 (talk) 20:52, 30 May 2008 (UTC)[reply]

You didn't say if you are restricted to gardening indoors. Assuming you must do it indoors, you would have similar problems with odors as a pet owner. If it were me, I'd put my worm farm in a terrarium with a tight lid, with sufficient water, sunlight, and plant matter growing to provide oxygen to the worms. The odor should then be fairly well contained. I can't imagine why you'd want a worm farm indoors, though.

Also, if you have no skill whatsoever at gardening and related activities, perhaps you should try another hobby? Raising goldfish or something? ~Amatulić (talk) 21:36, 30 May 2008 (UTC)[reply]

Do you wish to have a worm-farm for the sake of breeding worms, or as a means of producing compost or in order to compost your kitchen waste (rather than disposing of it in the trash.) All these choices have different answers. In general if compost gets smelly, something is going wrong. You either added something that killed "the right kind" of bacteria or your compost isn't getting enough air. You might consider using a tumbler. But read the reviews. (Don't trust anyone who says something about 2-4 weeks!) Some types aren't as convenient as they look. I remember seeing DIY instructions somewhere, but couldn't find them just now. If you don't trust your abilities, start small. Good luck.76.111.32.200 (talk) 22:31, 30 May 2008 (UTC)[reply]

What's the point? ----Seans Potato Business 22:56, 30 May 2008 (UTC)[reply]

If you have chickens or like going line fishing you might want to have the worms. (There are even people who maintain a small business by selling them.) If you have a garden you want the compost and if you want to pamper your "green conscience" you can recycle your biodegradable waste that way. (Warning: The average person produces more of that than is good for an ordinary sized vermicompost!)--76.111.32.200 (talk) 00:18, 31 May 2008 (UTC)[reply]

Sciences

How are the 3 branches of sciences, Chemistry, Biology and physics linked. Many physicists say that chemistry and biology are just subsets of physics. However physics seems to be the most theoretical science as it revolves around theories while Biology and chemistry seem to be less theoretical with clearer evidence. Chemistry and biology also seem less quantitative. Are chemistry and Biology just looking at the same thing as physics from a different perspective? Clover345 (talk) 21:16, 30 May 2008 (UTC)[reply]

Well, I've heard it said "without physics, there would be no chemistry, and without chemistry, there would be no biology." Yes, they are linked. There are even entire disciplines that consist of overlaps between physics, chemistry, and biology: biophysics, biochemistry, physical chemistry, chemical physics, and solid state physics, for example. Physics isn't necessarily more theoretical; we have applied physics as well as theoretical chemistry as disciplines of study. ~Amatulić (talk) 21:31, 30 May 2008 (UTC)[reply]

Technically all sciences should be linked as describing different levels and aspects of the same reality. In practice, though, the linkages are not easy to make. Part of it is a problem of scale—there's a limit to how many different elements you can describe in a physical system before the calculations produce chaotic and unstable outcomes, much less the computational difficulties. But beyond that, it's often the case that concepts developed within one context don't easily translate into another context—they're incommensurable, in the terminology of philosophy of science Thomas Kuhn. In any case, we wouldn't necessarily expect all current theories to mesh together perfectly, since a good number of them are probably wrong, incomplete, or just rough abstractions of how nature actually works anyway. You'd have to assume they were all correct to expect they all fit together perfectly, and at the moment nobody even thinks that holy-of-holies subject, physics, is entirely complete or correct (cf. the commonly cited problem that General Relativity and the Standard Model are incompatible).

And then, on top of everything else, there are also the problems you mentioned: the different branches of science, the different disciplines, have evolved very differently over time, some being more quantitative, some being more qualitative, some focusing on a rather strict empiricism, some putting emphasis on mathematical theorizing, etc. Theoretically, again, if they were all describing the same reality accurately and with the same degree of precision, they'd all find ways to translate, but they aren't necessarily doing that (accurately, anyway).

There's no historical or philosophical reason to think that many of the currently mature sub-fields of science should easily reduce to one another. Some do; some don't. In any case, reductionism has its limits. Technically quantum physics should correspond in some way to molecular biology and from there to cellular biology and organismic biology. But quantum physics doesn't really tell us anything useful about organisms. It's not a useful way to think about them and it's not going to give you an insights into them. Can everything be reduced to it? Maybe, maybe not. Would it help us understand very much if we knew how to reduce things to that? Not necessarily. At some level we can consider all of the different levels of nature to be somewhat autonomous, somewhat unconnected, because it simplifies things even more than reductionism does—even though reductionism appears to simplify things, it really complicates them, because you start having to talk in terms of emergent effects and other things that are pretty hard to express either mathematically or conceptually, and are far beyond our computational abilities.

One last, last comment. One of the most intense areas of research in the United States over the last 50 years has been nuclear weapons. The dream has always been to be able to have total computational understanding of all of the processes that go on inside the exploding weapons, from the quantum level up through the macroscopic turbulence effects. The largest supercomputers have been developed again and again to work on specifically this purpose. If any area should demonstrate a mature understanding of how various sciences reduce to one another, this should be it. But it doesn't quite work. They've never been able to design reliable nuclear weapons from purely first principles—they've always needed testing, test data, modeling on smaller systems. If they can't do it there, I doubt they can do it anywhere, just because this has been a major area in which they've tried to do it and have strong incentive to do it. Just my two (dozen) cents. --98.217.8.46 (talk) 23:06, 30 May 2008 (UTC)[reply]

World-class answer, .46. --Sean 01:15, 31 May 2008 (UTC)[reply]

I think *.46 was dancing around this issue, but let me say it anyway: even with a theory of everything and unlimited computational power, you can't derive biology from physics. People have, sometimes jokingly and sometimes seriously, proposed that the final theory of physics will be "all logically possible worlds exist". Imagine this is true for a second. Does physics reduce to it? Only if our world is the only logically possible world, which I find pretty implausible. Otherwise we still need general relativity and the standard model, not as a matter of practicality but as a matter of principle. And we still need physicists, doing the same things they do now, because "all logically possible worlds exist" doesn't tell us which extension of the Standard Model is the correct one in the world we find ourselves in. The same thing happens at every level of science. Physics can't predict penguins. -- BenRG (talk) 13:31, 31 May 2008 (UTC)[reply]

Put simply: To predict an outcome, you need both the theory and the initial conditions. While biology could be perfectly predicted from a theory of everything, it would require an impractical amount of knowledge about the initial conditions. With those initial conditions, you could predict penguins (give or take quantum effects, anyway...). --Tango (talk) 00:27, 1 June 2008 (UTC)[reply]

According to one former physics department chair I know: The 19th century was the century of chemistry, the 20th century was the century of physics, and the 21st century will be the century of biology... This is meant to the reflect that person's opinion about when the most important discoveries in each discipline occured/will occur. Dragons flight (talk) 23:11, 30 May 2008 (UTC)[reply]

Of course, historically it doesn't quite work out that way. Biology started to eclipse physics as "the" hot thing as early as the mid-1950s, and by the 1970s it was clear that physics wasn't going to come up with anything as earth-shattering as it had in the past, not compared to biology. --98.217.8.46 (talk) 23:42, 30 May 2008 (UTC)[reply]

I dunno, perhaps it could in a few months, though biology does need some more of a push to assert it's validity in the face of some silly doubts. Chris M. (talk) 17:16, 31 May 2008 (UTC)[reply]

Amino acid substitutions in engineering; phosphorylation

There are certain amino acid substitutions that can be made in genetic engineering to maintain a protein's structural properties but prevent phosphorylation of residues or mimic constitutive phosphorylation. What are these substitutions? ----Seans Potato Business 22:51, 30 May 2008 (UTC)[reply]

Typically single amino acid mutations to glutamic or aspartic acid will mimic the phosphorlyated state due to the net negative charge. Additionally a serine, threoine or tyrosine mutation to alanine is a good starting point for preventing phosphorylation at known sites. Wisdom89 _{(_T / ^C)} 01:45, 31 May 2008 (UTC)[reply]

Liquid

Do all liquids contain water? —Preceding unsigned comment added by 75.169.24.1 (talk) 23:41, 30 May 2008 (UTC)[reply]

No. To be "liquid" is just a state of matter. If you heat anything up to its melting point it'll become a liquid. No water necessary. Some pure elements are even liquids at just room temperature, like mercury. Water is a specific molecule that happens to be a liquid at room temperature (and even it is not always a liquid—it doesn't need to be too hot to become a gas, or too cold to become a solid). --98.217.8.46 (talk) 23:46, 30 May 2008 (UTC)[reply]

Hi. Also, some substances, such as Carbon dioxide, will go directly from a solid to a gas (or vice versa) at its evaporation/freezing point, in a process called sublimation, and the visible gas released does not have to contain water, but whether it usually does or not, I'm not sure, as the cold temperatures can condense water to become visible. Thanks. ~A H 1^(TCU) 17:31, 31 May 2008 (UTC)[reply]