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June 8

Spring board jump

Hi,
Can anyone confirm whether or not this movie clip is real or not (was there really such an event at the 25th annual Gymnastic Championships?). Thanks, --Fir0002 00:19, 8 June 2007 (UTC)[reply]

There are several things that suggest it is not.

The gymnast arising completely unscathed from being launched maybe 30ft in the air (no way it's 30 feet...15 maybe); no blood, no separated shoulder, no roll out to absorb the kinetic energy. He just hits some table, it breaks, and he's ok!
The reaction of the commentators and the people in the stands is quite lacking in emotion... no incredulity is detectable.
"There will be a deduction on the landing." If an apparatus breaks, and it is not the fault of the athlete, why would there be a deduction?
The narration at the very end "Not the official tools..." obviously fits that of some commercial.
The crawling through the air affect is just like you'd see in some old warner brothers cartoons and not like any real life accidental "body flying" scenes (say motorcycle or biking accidents)..
Did you see the guy with the green toolbox, acting like he's trying to hide something as the narrator says "I'd hate to have been responsible for that"? another possible ploy for comedic effect.
His horizontal speed when he launched from the springboard is as fast or faster than when he ran. Springboards work by redirecting momentum.. What was horizontal momentum becomes vertical momentum, so some horizontal speed must be lost in an effective jump.

Can anybody else think of a few reasons this is not a "real" event? I can't think of a good reason to believe it is real. Sorry. Root⁴(one) 04:34, 8 June 2007 (UTC)[reply]

BTW, I don't mind a critique of my critique. Root⁴(one) 04:36, 8 June 2007 (UTC)[reply]

(edit conflict) No, thank you! Because I personally strongly think that it is a fake and I'm trying to convince someone else! Another thing which I think is telling is how the gymnast flies up and at the peak he is stretched out horizontal, and then instead of making a smooth parabolic path landing pretty much head first he maintains this horizontal alignment pretty much throughout the descent. --Fir0002 05:51, 8 June 2007 (UTC)[reply]

The above assessment seems fair. This blog analyzes a Craftsman (tools) advertising campaign which is probably the source of this video. Nimur 05:49, 8 June 2007 (UTC)[reply]

OK, since you asked, here's a critique:

1. Surviving the landing in tact could be legit for a gymnast who knows how to jump, fall, etc, and is highly conditioned. Maximum height reached is about 4m, the table absorbs a lot of the impact, and the whole floor area is typically padded in gymastics events.

2,3. Agree that the commentators are a bit casual in their reaction and actual comments such as with the points deduction remark; the audience do react, though admittedly are perhaps too controlled.

5. The motion of the gymnast through the air doesn't worry me, it could be valid for such a situation where he is trying to gain control of his flight. This is different to being launched off a motorbike for example, so the flailing arms and legs could be genuine. I showed this to someone with more expertise in gymnastics and she agreed this could be a real reaction in flight, and that he would have some control over his body orientation in flight.

7. The breaking of the springboard could account for maintaining/increasing the horizontal speed as it throws him off his usual approach and in fact propels him up and forward; again this does not put me off. Remember a gymnast in a normal vault does have to maintain a fair degree of horizontal velocity when going over a vaulting horse, it is not all converted into vertical.

As far as the physics is concerned I'd say it's not impossible. But what gives it away is the guy with the green box and the voiceover that starts at the end. It's clearly an ad. I'd seen a shorter version of this before that ends when he hits the table, and from that was willing to take it as plausible, but the extra few seconds at the end clearly shows it as staged. I think the solution was actually in Fir0002's initial link. --jjron 07:07, 8 June 2007 (UTC)[reply]

I have seen the video without the sound. The flight path is impossible. The gymnast starts with a very high degree of forward rotational momentum and nevertheless stays head first in the air. He also flies too far given his speed. The video looks like a rig is used, attached to his shoulder and the playback speed is accelerated. However a very good stunt. I bet the landing *did* in fact hurt for real.

That's still possible if he's crawling hard with his hands. – b_jonas 22:15, 9 June 2007 (UTC)[reply]

Apparently it's a series of ads for Craftsman tools, with the inexplicable theme that they're the official tools of NASCAR, but don't work well for other sporting equipment maintenance. E.g. one about bowling. --TotoBaggins 16:21, 8 June 2007 (UTC)[reply]

If so, what a peculiar premise for an advertising campaign. Oh, two other problems with this video.

Now I'm not totally sure what the springboards they use in professional competition are like, but the only ones I've seen (in high schools) would not propel you anything like this if they broke, the spring mechanisms are not particularly strong. You'd be more likely to just slam into the vaulting horse. That always troubled me, but most people were willing to accept that as a given.
I'm happy to be corrected on this, but at the start you see him front on with a flag on his chest; as best as I can identify this is not the flag of any real country. --jjron 10:53, 10 June 2007 (UTC)[reply]

https://www.youtube.com/watch?v=6nccOvuYErk the answer.

Google Maps satellite imagery artifact

Can anyone explain this horizontal green strip (and the pink splotches under its left side)? Was it caused by a physical malfunction of the satellite's camera? —Keenan Pepper 06:19, 8 June 2007 (UTC)[reply]

Funny. Actually, much of Google's very high resolution images are not at all satellite photos but rather taken from survey airplanes. Sometimes, these you actual film, which is then scanned. So, it could also be a scanner malfunction. Best, ask the guys at Google Sightseeing. That is a blog on curious sightings on Google Maps, and they know such stuff. Simon A. 07:07, 8 June 2007 (UTC)[reply]

The western-most end appears to show waves crashing on a shore; in this case they've accidentally superimposed two separate images. Indeed, if you look 2.5 miles east of that strip, you can the crashing waves that this image came from; there's a reef and undersea ridge, which causes all the waves to break mid-sea, and the compiling program has accidentally placed one of the pieces of this image in the wrong place. The pink bits are probably artefacts of this; perhaps someone realised that they'd put an extra bit of film in the scanner, and tried to remove it just as the scanning light was passing under, resulting in a creepy double image. Laïka 08:09, 8 June 2007 (UTC)[reply]

A lot of Google map images are color-corrected. Some of the source images may never have been true-color to begin with! See Multi-spectral image for some explanation about why they use these - the canonical explanation is foliage cover studies. In any case, to make this data look like a "regular" aerial photograph, the colors must be swapped and adjusted. Also, even regular true-color photos may have had different exposure times, lighting conditions, angle, camera type... so these are normalized to a consistent color as well. That green bar looks like a color algorithm glitch that never got noticed. Nimur 09:31, 8 June 2007 (UTC)[reply]

(Here is a multispectral foliage study from NASA. The infrared band can give information about plant health by detecting varied chemical levels such as chlorophyll, or even just water concentration). Nimur 09:34, 8 June 2007 (UTC)[reply]

Nobody thinks it's a secret government island, then? 213.48.15.234 09:40, 8 June 2007 (UTC)[reply]

Shhhh. Someguy1221 18:16, 8 June 2007 (UTC)[reply]

Which bird is that?

Please see this question about this bird:

Thanks, Lior 07:51, 8 June 2007 (UTC)[reply]

My guess would be an ibis, or more specifically a sacred ibis as they were a big thing in Ancient Egypt. Is there any reason it wouldn't be that? That thing sticking out the back of it's head looks weird though, almost looks like some type of pterosaur. --jjron 09:11, 8 June 2007 (UTC)[reply]

I was amazed to find out about WikiHieroglyphics, which can be added to any article. I'm a bit surprised and disappointed that there is not a Hieroglyph-language version of Wikipedia yet.... Nimur 09:37, 8 June 2007 (UTC)[reply]

The northern bald ibis (Geronticus eremita) was also revered, and has a little bit of a crest. It represented akh. --mglg_(talk) 16:35, 8 June 2007 (UTC)[reply]

I also posted an answer here [1]. — Zerida 19:14, 8 June 2007 (UTC)[reply]

Ignoring that everybody knows that the ibis is the sacred bird of ancient egypt and also ignoring that the Secretary Birds habitate now doesn't extend to egypt, i'd think it has some similarities. 84.160.213.25 20:43, 8 June 2007 (UTC)[reply]

Thank you Zerida, thank you all. Kindly notify me if you have any insights on the Egyptian engravings of the Shoebill mentioned here. Cheers, Lior 04:44, 9 June 2007 (UTC)[reply]

Cat Savaging.

A friend asked me about their cat starting to eat her kittens. Luckily all but 1 were saved. I found the article on savaging, but that mainly applies to pigs. Can anyone shine light on why she might have done this? 213.48.15.234 13:17, 8 June 2007 (UTC)[reply]

This article lists these reasons:

Mother can't "switch off" hunting behavior
Mother thinks kitten is defective
Mother thinks kittens have poor chance of survival anyway (due to food shortage or external threat)
Handling by others obscures mother's scent on kittens, so she doesn't recognize them as her own
(Rare) Excessively enthusiastic grooming of the kittens kills them

It's important to remember that the mother has expended a lot of energy in the pregnancy and birth, so making an easy meal of a kitten can be a very advantageous behavior. --TotoBaggins 16:43, 8 June 2007 (UTC)[reply]

We have more on other animals at Cannibalism (zoology)#Filial cannibalism. Maybe that section should be merged into Savaging? (Please discuss at Talk:Savaging). — Sebastian 16:57, 8 June 2007 (UTC)[reply]

It's also been known for female budgerigars and cockatiels to savage their young for no apparent reason. --Kurt Shaped Box 21:18, 8 June 2007 (UTC)[reply]

She was simply exercising reproductive choice. Surely no one around here has a problem with that? alteripse 00:54, 9 June 2007 (UTC)[reply]

Why not? I can think of some humans who should have done this... — Omegatron 00:57, 9 June 2007 (UTC)[reply]

Tomcats will supposedly sniff out kittens which are not genetically their offspring and kill them. This has clear Darwinistic advantages for the tomcat's passing along his genes. Would there be some Darwinistic advantage for the mother doing that if the biological father has moved on and there is a new tomcat in town? Edison 02:23, 9 June 2007 (UTC)[reply]

A change in environment, increased stress levels or the presence of other animals can all lead to behavioural changes in animals that can result in infanticide. Lab mice will often kill the own pups, especially in their first litters. There appears to be pheromonal cues between mother and pups the promote a "caring" relationship. If these cues are disrupted or masked, or the mother is unable to detect them then she may kill her pups. Consistant with this, animals with a non-functional olfactory system are often "bad mothers" and their pups need to be fostered. There may well be a good evoluytionary reason for it (one could hypothesize about conservation of energy resources) or it may be an artifactual. In the presence of other animals, there is likely to be pheromonal cues involved, see also the Bruce effect. Rockpocket

Current Carrying Capacity

How is the current carrying capacity of a wire afected by it being a single strand wire or a multi-strand wire? Is there any experiment designed to take readings practically and find out? Can I design such an experiment? Andhow will the circuit diagram of this experiment look? —The preceding unsigned comment was added by 221.134.43.30 (talk)

Current capacity is governed by the temperature the wire is allowed to reach before it is considered failed (the insulation breaks down). The temperature increase is caused by Joule heating. A wire with a higher resistance will create more heat for a given current, thus be rated for less current. You can easily measure resistance of the two wires. Or consult a chart here. Strangely enough, the chart makes no distinction between solid and stranded wire. anonymous6494 15:25, 8 June 2007 (UTC)[reply]

Please do not experiment with high current or high voltage electricity, unless you are fully trained and qualified to do so, and have the appropriate safety equipment, since it can cause burns or shocks. Were you considering the cross sectional area of the conductors? When you mention single conductor versus stranded wire, you have to consider the frequency of the power to be transmitted. As the frequency increases, electrical current travels more on the skin of the wire and less on the interior.Skin effect Bus bars in an electrical power substation are often hollow, because the center would carry less current than the periphery. If the surface of a hollow conductor is silver plated (not done on the aluminum tubular bus bars) the conductivity is further increased. For direct current or low frequencies the skin effect is negligible. For audio frequency or higher strranded conductors should have less impedance than solid conductors. If you were designing an experiment , you would need a safe method of measuring the temperature rise of the conductor as the current is increased, since the limiting factor may be the safe operating temperature of the insulation. If the conductor is uninsulated then there is still a limit on the max operating temperature, since a hot conductor like bare overhead transmission wires may start things on fire, cause insulators to crack, or expand, soften and sag until they touch a tree and have a fault to ground. SeeElectrical wiring , Electrical conductor, American wire gauge , Electrical impedance, Electrical resistance , Resistivity , and Current density. You wiill find useful though often highly jargon-laden information in your localities electrical code, such as the National Electric Code in the U.S. [2] . When several conductors are in a common conduit, they each may produce heat, so there is a limit on how many can be pulled into the same conduit. Edison 15:35, 8 June 2007 (UTC)[reply]

Edison missed one useful link: Litz wire.

Atlant 16:41, 8 June 2007 (UTC)[reply]

That's User:Edison, not Edison, of course. There's a reason why he missed it: it wasn't in Category:Electrical wiring (and that category wasn't in Category:Electrical components, btw.). — Sebastian 17:16, 8 June 2007 (UTC)[reply]

The wire going to the earpiece of my 1910 wall telephone looks like Litz wire. Tiny little wavy strands, mechanically weak, hard to solder, prone to oxidize because not tinned. Does not seem like a good choice for high current at power frequencies, but what do I know?Edison 02:21, 9 June 2007 (UTC)[reply]

Telephones commonly used tinsel wire: multiple strands of copper foil wrapped around a fabric core. It's got reasonable tensile strength (owing to the fabric core) and is very flexible, but it is fine gauge and hard to terminate. In phones, crimped connections were almost always used to terminate tinsel wire.

Atlant 20:49, 9 June 2007 (UTC)[reply]

Another fascinating (to me, anyway) concept is ACSR cable. (I've only just started this article; feel free to improve it.) —Steve Summit (talk) 22:35, 9 June 2007 (UTC)[reply]

Yeah, ACSR is the lifesblood of electric utility overhead transmission. Copper or aluminum would be weak and prone to sag and break under its own weight in the larger sizes. The steel is along for the ride in terms of current carrying, and the aluminum is along for the ride in terms of tensile strength. There was one a power line span at Tacoma Narrows (scene of an engineering farce where a bridge fell down) which used steel cable only, and which a journal once described as the "world's largest outdoor space heater" because of the higher resistance of steel. Edison 20:17, 10 June 2007 (UTC)[reply]

HDTV

My friends and I are having a stupid argument. I was stating that the colors are not real on a HDTV program with compatible tv. I was woundering if your crew could better knowldge me on this subject? Is there a way to see these colors in real life or is it impossible for the human eye? I know that these colors are digitaly inhanced but my argument with my friends is that it would be unlikley to ever see a color that bright and clear with perfect eyesight. If you could please ( CLEAR ) this up I would appreaciate it greatly.

Thanks Chris

Your question makes very little sense. All colors that can be seen under any circumstances are real. The only colors that are not real are ones that are completely made up, such as the color "zanthripodis" - I just made that up. It isn't a real color.

The concept of colors not being "correct" came up with NTSC (commonly called "Never The Same Color"). HDTV does not have that problem because it is not NTSC. --Kainaw ^(talk) 14:14, 8 June 2007 (UTC)[reply]

Some colors you may not be able to see on an HDTV due to the limitation of the human eye. It is believed that most humans can see somewhere around 24 bits of color. See Color depth#Truecolor. Whether this is what you are talking about, or the topic above, I am unsure.--GTPoompt (talk) 14:23, 8 June 2007 (UTC)[reply]

Real life can be very colorful. Colors you can see in nature can have a wider range of hue, value and chroma than colors which can be displayed on any HDTV or motion picture screen, because the three real primaries used create a triangle in the color space, and nature has colors outside that. See Color vision. Yet with lab experiments, you can perceive colors wich do not exist in nature. See Imaginary color. Edison 15:13, 8 June 2007 (UTC)[reply]

You really have to ask yourself what is this "real" quality your friend is looking for. Your eye perceives color because (most) have at least 3 different types of color cone cells. There is in essence a light that has a specific frequency that we might call "yellow", but your eyes would not be able to distinguish between "true" yellow, and some light that happens to be a certain combination of "true" red and "true" green (whatever "true" is in this instance, from the cone cell article we may want to call, light with wavelengths around 564nm and 534nm red and green respectively may fit some definition of "true"). Your HDTV would generate its colors by a linear combination of light wavelengths sensed by the three color cones. I could see where the "blue" of HDTV may not match the blue of my monitor or blue of some old TV.

Color perception has been discussed on this reference desk recently. hmmm, I see, May 3, May 21 (although the huge animated gif is a bit silly). Also look at Color vision, Tetrachromacy, etc. Root⁴(one) 15:30, 8 June 2007 (UTC)[reply]

I've heard that people who have tetrachromatic vision often describe television and computer monitors as having very odd coloring, because of the way those displays are optimized for trichromatic viewers. --JSBillings 16:42, 8 June 2007 (UTC)[reply]

The limits of the gamut is probably what's being referred to here.

Atlant 16:43, 8 June 2007 (UTC)[reply]

My interpretation of this question seems to be different than everyone else. I think they were asking if HDTV exaggerates colors to make them brighter and more vibrant than in the original object. Since just about any TV has a color adjustment that allows you to crank up the color well beyond what you see in the real world, that certainly is possible (and was also possible on old TVs). Just turn the color down to a more realistic level if it bothers you. Some films, like Kodachrome, definitely had the tendency to exaggerate colors ("gives you the greens of summer, makes you think all the world's a sunny day"). StuRat 17:14, 11 June 2007 (UTC)[reply]

Sugar Maple burning

Does the burning of sugar maple wood produce a sweet or otherwise distinctive aroma? HYENASTE 14:45, 8 June 2007 (UTC)[reply]

No. Apple or cherry wood does have a slight aroma. (personal opinion from burning wood, unsourced) --Zeizmic 15:23, 8 June 2007 (UTC)[reply]

I never burned sugar maple, so I don't know. But I hesitate that it wouldn't be a "distinct" smell. Burning Pecan and burning Oak are different experiences and IIRC a different smell was part of the experience. Although I don't know how much of it may be due to the fact when I burned Pecan, the wood was more recently cut. Mesquite definitely has a distinct aroma.... makes me think of barbeque due to it often being used in barbeque preparation. (Wow, is that a long winded way for me not to answer the question or what?)Root⁴(one) 15:59, 8 June 2007 (UTC)[reply]

future eye colour change

do you think in the future it is possible to change eye colour or are there any developments on it right now?, like an advanced form of laser surgery for people who have 2 different coloured eyes or who simply want to change their colour

There are contact lenses that alter your eye colour. These can be purchased quite cheaply already (http://www.lensesbymail.com/colored_contacts.htm) is just one site that sell them. No idea whether or not you can have permanent surgery to change them, but I guess these do the trick for people who want to have 'blue' eyes (or whatever). ny156uk 17:15, 8 June 2007 (UTC)[reply]

The Eye Color wiki page has some information about how eyes get their color, and how that color can change. There definately seems to be a genetic component, but the color can also change due to the amount of color they receive. --JSBillings 18:51, 8 June 2007 (UTC)[reply]

Red Rice Vs. Brown Rice

Which of the two is better for health and why? -- Prax

You may be referring to red yeast rice. The fermentation process used to make it produces the cholesterol-lowering compound lovastatin, which gives it additional health benefits, but also brings it under the purview of the FDA. Here's a good article about it. --TotoBaggins 16:57, 8 June 2007 (UTC)[reply]

If s/he's not referring to red fermented rice, s/he might be referring to red rice or Bhutanese red rice. I vote for red rice, which is widely available in Asian stores, and is a bit similar to wild rice. Anchoress 21:12, 8 June 2007 (UTC)[reply]

This question was previously asked on May 28. There was not a strong consensus. Nimur 19:50, 10 June 2007 (UTC)[reply]

The red rice article is not particular clear. Is it normall milled? If yes, then unmilled brown rice is likely a better choice. If not, then I don't see any reason to assume they are much different Nil Einne 17:26, 11 June 2007 (UTC)[reply]

Dietary fiber

Could someone please elaborate on the (positive) health impacts of dietary fibers? The only immediate health impacts I encounter is increased, and often painfull, flatulence with corresponding social impacts. Just why should any short-chain fatty acids from fermetation have positive effects on my health, and if so, wouldn't it be cleaner just to drink vinegar or something like that? 84.160.213.25 19:52, 8 June 2007 (UTC)[reply]

Dietary fiber has a lot of information...Someguy1221 20:50, 8 June 2007 (UTC)[reply]

Yes, but not to my question. I've read that before. 84.160.213.25 21:19, 8 June 2007 (UTC)[reply]

Dietary fibre has two very significant health benefits: it decreases the risk of colon-related disease such as colon cancer and hemorrhoids, by increasing the bulk and softening the texture of stool (both), and diluting toxins and moving them through the digestive tract more quickly (colon cancer); and it helps regulate blood sugar levels. According to some recent articles I've read, the latter is true of soluble and insoluble fibre (will look for refs later). Anchoress 21:25, 8 June 2007 (UTC)[reply]

Im especially interested in those refs. My question is insistingly on the why, not on the weasel-wording everybody knows. For the hemorrhoids, I know from own experience that a pressure on the belly increases the risk or even provokes this. Increasing the bulk increases the pressure. (I happened to solve my personal problem with the help of two catalogs for electronic parts liftening the base of my computer monitor by 2.5 inches, 4 years ago and never had any such problems again). As for diluting toxins, im realy not sure. As for my experience, I have more problems with a fibre stuffed stomach producing gases. 84.160.213.25 22:01, 8 June 2007 (UTC)[reply]

The "portfolio diet" showed a decrease in cholesterol comparable to statins (drugs). Lots of fibre was a key component. Some participants found the food so filling they couldn't eat it all, so weight loss was a side effect also. iames 22:03, 8 June 2007 (UTC)[reply]

Sorry if this sounds offending, but most people in the world still are happy if they have enough to eat. Globaly, only a luxorious minority has concerns not to get overweighted. Albeit I'm part of this lucky minority, obesity is not a problem to me. 84.160.213.25 22:17, 8 June 2007 (UTC)[reply]

It's a substantial minority -- 1 billion overweight and 300 million obese. I would claim weight regulation as a health benefit of a high-fibre diet. iames 22:36, 8 June 2007 (UTC)[reply]

It is an issue for the overweighted, then, not a general benefit of dietary fibres as such. Many pepole have Lactose intolerance, still milk is not labelled as poisonous. So why should dietary fiber be labelled healthy if it is healthy for only one out of six humans? 84.160.213.25 22:46, 8 June 2007 (UTC)[reply]

Are you just trying to get your mom to not cook beans any more? iames 22:57, 8 June 2007 (UTC)[reply]

Beans, though known to increase flatulence, are low in dietary fibers compared to the rich nutrition value in carbonhydrates and proteins. 84.160.213.25 23:04, 8 June 2007 (UTC)[reply]

My point is it's not clear what you're looking for. You asked for health benefits and some were provided. I would also claim that 5 out of 6 humans are not overweight in part because they consume lots of fibre. But there are benefits other than preventing obesity. iames 23:12, 8 June 2007 (UTC)[reply]

So again to make it very clear, my point is why (by what effects, other than that the stomach is so stuffed that some people just cannot feed themselves to death), should dietary fiber be healthy. Especially, why (by which process) are the mentioned short-chain fatty acids from fermetation healthy and if so, why isn't it possible (or is it?) to gain the same effects by directly eating/drinking these acids? 84.160.213.25 23:23, 8 June 2007 (UTC)[reply]

And while we are mostly off topic anyway, you might have a look at genesis, 1:29 and 1:30, just for curiosity. (This is not my point or reason, just an interesting extra) 84.160.213.25 23:35, 8 June 2007 (UTC)[reply]

For anyone who doesn't have a bible handy:

29 Then God said, "I give you every seed-bearing plant on the face of the whole earth and every tree that has fruit with seed in it. They will be yours for food. 30 And to all the beasts of the earth and all the birds of the air and all the creatures that move on the ground—everything that has the breath of life in it—I give every green plant for food." And it was so.

--Anchoress 23:41, 8 June 2007 (UTC)[reply]

Right. This gives me a little problem with tea, but then, I'm not eating the leafs, I'm only bathing them in hot water ;-) 84.160.213.25 23:57, 8 June 2007 (UTC)[reply]

Keep in mind that the fiber in your diet might not be digestible by "you", but your gut and intestinal flora require it, and healthy digestive flora is beneficial to you as well. --JSBillings 00:05, 9 June 2007 (UTC)[reply]

Did I already mention the social impacts caused by the increased faltulence from the said healthy digestive flora? 84.160.213.25 00:08, 9 June 2007 (UTC)[reply]

Yes, You have mentioned it. flatulence is caused by your gut bacteria, but you'd be considerably less healthy without them. Most often, passing gas is due to your gut bacteria metabolizing sugars that would normally be metabolized by your own digestive systems but for some reason you could not, for example, with lactose intolerance, the disaccharide lactose isn't metabolized in the upper gut. --JSBillings 00:14, 9 June 2007 (UTC)[reply]

Also, bible verses and wikipedia might not be the best source of nutritional information. Talk to your doctor. --JSBillings 00:21, 9 June 2007 (UTC)[reply]

Now that sounds more interesting. For narcistic reasons I've always thougth of me to be one of a kind with something special that no one else had. I never, though, thought of it beeing my digestive system. I definitely don't have a lactose intolerance, but something is metabolized by this healthy (well, by itselve, but not to me) digestive flora. The doctor recomends anis and carraway, which speeds up digestion even more, worsening the problem. 84.160.213.25 00:27, 9 June 2007 (UTC)[reply]

Speeding up your digestive tract might be your doctor's intent, give the bugs in your belly less time to digest the undigestible bits left over from your digestive system. I'm not a doctor, so I can't be sure. --JSBillings 00:34, 9 June 2007 (UTC)[reply]

Yea, I know how my doctor works, thats why I'm not seeing him again unless I can't fight it. He thinks: 98 percent of all my patients with digestive problems are women who haven't been to the toilet for at least three days. (bad enough) So I will treat all 100 % to increas digestation and the 2 percent troublemakers will see what benefits from their rebellios acts against my treatment. 84.160.213.25 00:47, 9 June 2007 (UTC)[reply]

(unindent) Beans are actually a great source of fiber. 4 ounces of pinto beans contain 4.5 grams of fiber. As the jingle says (in one version) , "Beans, beans, the musical fruit. The more you eat, the more you toot. The more you toot, the better you feel- so eat some beans with every meal!" Edison 02:13, 9 June 2007 (UTC)[reply]

It seems as though you wish to contradict well established medical facts based on your opinion, which is interestingly unfounded. If you want to understand exactly why dietary fiber is considered "healthy" then you should probably read it for yourself in a medical journal. It takes more than painful toots to suggest that what you ate was not healthy or had a null impact on your health. You should really bring up a specific problem with a specific study or article since there are so many. 12.127.48.250 05:23, 9 June 2007 (UTC) mrdeath[reply]

A milestone book on medical quackery and the lack of conceren by the US government, "“100 Million Guinea Pigs: Dangers in Everyday Foods, Drugs, and Cosmetics,” was published by Consumers Union in 1933. It correctly decried the lack of interest by the federal government in making sure that medicine was safe and effective, but it also criticized calls by the government and medical authorities for people to eat fiber, a view that the organization no longer holds to. The US Department of Agriculture now recommends 2 cups a week of legumes if one is consumiong a 2000 calorie diet [3] . This is clearly less than the jingles "beans at every meal) unleess one consumed 2/21st cup or .76 fluid ounce per meal. They recommend up to 25 grams/day of fiber per[4] . Beano (dietary supplement) is a product which claims to reduce tooting. Edison 17:13, 9 June 2007 (UTC)[reply]

I would only list the U.S. government as a secondary source concerning this issue. They are just reading the same articles I am, and not publishing them. Then they make recommendations based on the scientific consensus. Seriously... 12.127.48.250 05:24, 10 June 2007 (UTC) mrdeath[reply]

As for the "social impacts (of farting)", these can be lessened by use of Beano and having fiber mainly on days when you aren't expecting to go to a party that day or the next. Also, once your digestive system adjusts to a fiber-rich diet, the problem will somewhat lessen. StuRat 16:54, 11 June 2007 (UTC)[reply]

Stopwatch issues

Taking into consideration two stopwatch issues (different reaction upon start signal among athletes and different human reaction upon pushing the stopwatch itself), are there a significant amendments in world and Olympic records? --Brand спойт 23:06, 8 June 2007 (UTC)[reply]

Sorry this is useless (as it's not an answer) but i've often wondered this myself. With times seperated to the 100th of a second I often wonder what the 'error' margin is. Good question - I'll dig about online and see if I can find anything. ny156uk 23:12, 8 June 2007 (UTC)[reply]

Speaking of which...(http://www.slate.com/id/2120957/) Well worth a read ny156uk 23:13, 8 June 2007 (UTC)[reply]

By the way, apparently existing margin time limits are to compare roughly similar records IMHO. I tend to agree that they have nothing to do with the reaction issues. --Brand спойт 23:28, 8 June 2007 (UTC)[reply]

When you say "different reaction upon start signal" it sounds like Bill begins running .2 seconds after the starter pistol but John starts running .25 seconds after the starter pistol. So? This means Bill will have a 0.05 second head start ath the beginning of the race, and if he and John can run equally fast, Bill will win. Good for him. I have done reaction time experiments, and not every one responds equally fast to a stimulus. In the 19th century, the time observers at the Greenwich observatory used a telescope to synchronize the master clock by pressing a pushbotton to create a mark on a time chart when a sequence of stars crossed the prime meridian (Airey's Disc). It was found tha different observers would press the button at slightly different times when they saw the star cross the index point. This became known as the "personal equation" and it was measured and allowed for. People have slightly different synchronicity. Runners or swimmers or members of a brass band have to learn to deal with this or they lose races or do false starts (if athletes) or get yelled at (if musicians or psych experiment subjects). The question of "different human reactions upon pushing the stopwatch" should be dealt with by the instrumentation itself, so that different athletes are timed by the same mechanism, and they all get the same start signal. (When I was 9 years old I saw a Cub Scout soapbox derby where each competitor was timed by a different person with a different stopwatch, and I objected to it at the time, alas to no avail.) Edison 02:06, 9 June 2007 (UTC)[reply]

On the different person/different stopwatch front, you'll be pleased to know that the Olympics tended to take more care even in the years before automatic, electronic timing. In the 1932 Games, track events were timed by twenty-five people, each with a manual stopwatch. Their results were averaged to get the runner's time. TenOfAllTrades(talk) 02:29, 9 June 2007 (UTC)[reply]

Here's an article about how timing is performed for various Olympic events. Different sports' governing bodies specify rules for determining world records, including the requirements for timing. (In track and field events, it is the International Association of Athletics Federations. See Rule 260 for details.) TenOfAllTrades(talk) 02:29, 9 June 2007 (UTC)[reply]

So since the speed of sound is 1128 ft/sec, that would mean races where the athletes are spaced more that 11 feet from the starting gun would lose about 1/100 second for every 11 feet. This is independant of their reaction times but seems built in to the race. Now if they had start lights instead of a gun, that might be better.... --Tbeatty 07:40, 9 June 2007 (UTC)[reply]

Nice idea. --Brand спойт 09:14, 9 June 2007 (UTC)[reply]

Anytime there are different stopwatches and different stopwatch operators for different competitors, there is the strong possibility of cheating or of unfair recirding. When Ten says the 1932 Olympic track events were timed by 25 observers with 25 stopwatches, does that mean 25 per competitor (overkill) or 25 for 25 runners (a real problem). I remember the olympic skating and gymnastic events in the days of the Soviet Union, when a judge from a satellite country would always give a high score to the Soviet competitor. Similar bias could have influenced pressing a timing button. One would get in the curious position that runner A took 60.1 seconds and runner B took 60.0 seconds, but judges saw A cross the finish line first. There are clearly 2 issues: medal awarding for the game, and determining if a new Olympic or world record was set.It would be easier to judge who crossed first(breaking the paper tape) than who crossed 3rd in a pack. [5] says "electronic timing" was used in the 1912 olympics. It does not say how the start signal initiated the timer or how the finishes were recorded, because apparently they did not have photocells until the 1940's. Millisecond timers were available by the early 19th century, using a tuning fork for accuracy. It says they used a "photofinish" in 1912, which might have been as simple as a string tripping a camera shutter like Eadweard Muybridge used to get motion pictures of a galloping horse in 1878. Edison 16:51, 9 June 2007 (UTC)[reply]

That's only true if the gun is besides the athletes. If it's ahead or behind them, the difference would be much smaller. By besides, I of course mean that it's about on the line they are starting from, which might not be perpendicular to the pitch in eg a 400 m competition; in this case ahead and behind has to be adjusted accordingly as well.

Also, if the gun is besides the athletes and is not far enough, the sound volume that reaches them might be different, which might affect their reflexes. – b_jonas 00:00, 10 June 2007 (UTC)[reply]

At major events, each athlete's starting blocks contain a loudspeaker; all are connected to the electronic timing system. When the race starts, an electronic tone is generated which is played simultaneously from each athlete's speaker. This page has a description of the system, as well as a picture (about halfway down the page) of a set of starting blocks with a speaker. Consequently, each athlete should hear the same tone, at the same volume, at the exact same time. TenOfAllTrades(talk) 00:39, 10 June 2007 (UTC)[reply]

DNA change

After watching a particularly ridiculous episode of Star Trek: Voyager, I'm finally curious enough to ask: is the common science-fiction proposition of DNA change possible? If all of the DNA in a human body was changed to newt DNA, would it actually transform into a newt or simply die as new newt cells are unable to survive in the still partially-human body? --⁪froth^t 23:43, 8 June 2007 (UTC)[reply]

There was something similar on CSI after an organ donation or bone marrow transplant I think. Not exactly the same as Voyager. Anchoress 23:46, 8 June 2007 (UTC)[reply]

You'd have to somehow replace all the DNA in existing cells without causing the body's antibodies to attack all the changed tissues. The immune system would be pretty weak at the time so I imagine infection would be a huge risk. Plus, you'd have to still have cells functioning as they normally do during the transition. Maybe with the magic of Star Trek transporters/replicators. --JSBillings 23:57, 8 June 2007 (UTC)[reply]

The embryonic developement is a complex process. If it was possible to instanciate a biological beeing by just activating one set of genes our DNA could be substantially shorter. That's to say: no, to polymorph to a newt, we would need not only all the genes of a newt but also to activate them in the right order of development and by nature this starts with a newt egg, not with a fully developed human body. 84.160.213.25 00:15, 9 June 2007 (UTC)[reply]

Yes, this is correct. We won't turn into newts if all of our cells' DNA are replaced with newt DNA. Embryonic development is very specific and mechanistic. From the single cell, DNA produces specific proteins. Such proteins then drive gene expression. Gene expression is very complex; for example, the activation of a certain gene depends on the interactions of multitudes of proteins on the DNA. And remember that each of those proteins is produced from a specific gene. Repeat the same cycle, and you get the idea.128.163.171.68 20:10, 9 June 2007 (UTC)[reply]

Let's say all the DNA were replaced simultaneously. The structure of the body would still be human, so everything would begin to fail to work properly. Even if you somehow overcame this problem and you ended up with a roughly six foot tall newt, that would cause all sorts of scale problems, e.g. the legs wouldn't be able to support the extra weight. Clarityfiend 05:12, 9 June 2007 (UTC)[reply]

If a patient has a genetic disease where a certain cell type malfunctions it would be great to be able to amend the DNA in these cells to make them perform correctly. This is the stated goal of gene therapy. Of course, changing a sick man into a healthy man is maybe a less dramatic change than changing him into a sick newt, but definitely a more useful one. As you can read in our article, we are still at the very beginning but researchers still seem to be optimistic. Simon A. 08:15, 9 June 2007 (UTC)[reply]

Just to be clear, the goal of gene therapy is usually vastly different from what was suggested in the original question. The goal is usually only to get sufficient cells of the type that is malfuctioning expressing the 'correct' gene that you can alleviate the condition. The goal is not to change the defective gene in every single cell in the body. I don't know the numbers for sure but the magnitude of difference is probably at least a few tens billions Nil Einne 17:23, 11 June 2007 (UTC)[reply]

I would find it more believable if the person was changed into something much closer to human, like a Neanderthal, since there's no way something half human and half newt could survive the transition. StuRat 16:35, 11 June 2007 (UTC)[reply]