Wikipedia:Reference desk/Archives/Science/2012 December 1

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December 1

Magic bread or...?

Beginning at about 4:40 in this video, an illusionist does something that I'm pretty sure is impossible... At least, in all the years I've spent studying sleight of hand and the like, I've never seen anything that should enable one to do something like that. Any thoughts on how that's done? Evanh2008 ^{(talk|contribs)} 06:35, 1 December 2012 (UTC)

Looks like a camera trick to me. That is, they stop filming, put a small piece of bread in his hand and let him pull it out, then stop filming and put a larger piece of bread in his hand, etc. I think I can see the cuts. Also, that bread is just too large to have been up a sleeve, etc. This does, of course, mean that the "audience" were just shills, pretending to be impressed. (The trick camera work could also have involved hiding the full piece of bread behind a green screen, then digitally replacing the green screen with the background, but I think it's just jump cuts.) StuRat (talk) 08:48, 1 December 2012 (UTC)

BTW, does the person who posted it know his name is listed as "Yi Fart of Magic" ? :-) StuRat (talk) 08:51, 1 December 2012 (UTC)

I don't see any cuts. It looks like green screen to me, with actors for the "audience reaction". Red Act (talk) 15:48, 1 December 2012 (UTC)

Actually, there is a cut before the audience reaction. So the video could start with a green screen effect, followed by a real audience reaction to a simpler trick that produces a baguette. Red Act (talk) 15:55, 1 December 2012 (UTC)

• It's behind his back and he's pulling it around. Look how flexible it is. Looie496 (talk) 17:03, 1 December 2012 (UTC)

I watched a program once a while back showing how magicians use powerful retractable strings to exchange items from either up their sleeves or from behind their clothes. For the long bread loaf trick, he appears to be using one coming from under his very large shirt collar which becomes pulled upward by the bread, before it drops back down to his chest... perhaps due to the string pulling the large dough ball into his shirt after the bread was pulled out from underneath (the large loaf must be compressed within a smaller diameter tube to reduce its bulk and the tube might be sealed to maintain an increased air pressure within the bread, causing the bread to expand rapidly when removed, and in addition, the air pressure may help expedite its removal from the tube too). He would simply need to extract a difficult to see hook mechanism (behind the collar and partially visible at the 3:24 mark) and then uses his free hand's thumb to plant the hook firmly between his fingers behind the dough. Note also that when the collar is raised it is not folded in place like a typical collar, but it separates from the shirt when this happens, allowing the bread to remain hidden behind cloth from viewers on either side of him. It also appears that the croissant may have been undercooked and turned inside out through a small cut centered on its uppermost edge. He would either had to given it to the deli prior to the taping or switched their dough for the prop, perhaps during the cuts. -Modocc (talk) 23:40, 1 December 2012 (UTC)

I've studied magic for many years and while i certainly wouldn't claim to be an expert, I'm pretty sure there is a camera trick involved in the large baguette production, some magicians are definitely not against using such tricks. Vespine (talk) 05:55, 2 December 2012 (UTC)

Not to my eye or reasons.. The loaf of bread can easily be concealed once compressed and he just so happens to be wearing something that is poking out slightly from beneath his collar (and its not attached to the collar because its poking out from the shirt in later frames), so what is it? Had he used a camera trick, he would have no need to be wearing that unusually tailored shirt or any hardware beneath it. Why would the collar be lifted? He also may also being using string to swap the colored rubber bands and the use of retractable strings (or elastic bands) to remove or disappear objects (the dough in this case) is a common method of concealment. Furthermore, his various audience's reactions appear genuine to me and I don't see any hint of a green screen (I've seen these screens used countless of times and they tend to be noticeable for various reasons). That he is able to pull his tricks off as well as he does simply speaks highly of his skill. For these reasons, I don't believe he resorted to doing a cheap camera trick that just about anyone could do. But of course, I could also be wrong... :-) --Modocc (talk) 06:23, 2 December 2012 (UTC)

I don't see a large collar and a hook. I see a scarf (presumably used in another one of his tricks) and a microphone. And the bread would have to make a 90 degree bend to come out from under the scarf. I believe he just bumps the scarf with the large piece of bread. And, if green screening is done properly, it's not visible on the final video. StuRat (talk) 07:10, 2 December 2012 (UTC)

It is a highly flexible piece of bread, and a narrow tube that conceals it could help with bending it if its been pulled out to his hand (the hook itself, should one be used, could be smaller and less visible than the mic), but his hands may not be close enough to his shirt for that not to be noticeable. The bread seems to expand some, up until he breaks it in two (conformation bias on my part I'm sure). Plus, it would be to his advantage to be able to perform the trick on demand (for more gigs) than only with a green screen production. But that's what his videos are, and of course I was completely wrong about the shirt. Fair enough. My vision isn't what it used to be. -Modocc (talk) 08:23, 2 December 2012 (UTC)

The bread does seem to grow in size between cuts, which is one reason I suspect trick photography. StuRat (talk) 08:45, 2 December 2012 (UTC)

re: green screens, that's called the toupee fallacy, you've seen green screens only when they've been executed poorly, if they were done well you didn't notice them, so you think they are all poor. Also, reproducibility is not a factor for a magician doing a YouTube or television performance, I don't think ALL the tricks were rigged with camera tricks, but I do thing the baguette one in particular was. As for reactions, they are actors, they are paid to give genuine looking reactions. Have you seen this clip? Criss Angel is a far more known magician, in the west at least, and this clip was exposed as completely staged, he used actors, one of them an actress with a Hemicorporectomy and creative editing, that's it, no "magic" involved at all. I agree, it's cheap, but some magicians are not beneath using them. Vespine (talk) 08:46, 2 December 2012 (UTC)

Most seemingly impossible shots are green screen, thus it is likely that it is a well-executed green screen. This too is an inductive leap and I didn't say all green screen are poor. I was just pointing out that there was no validating evidence yet given showing that it is one (and lots of so-called "evidence" and testimony that it is a green screen), but I do agree that its probably a green screen. -Modocc (talk) 09:26, 2 December 2012 (UTC)

@StuRat Yes, trick photography is definitely possible. On the other hand, after its initial rapid inflation (think cosmology here, :-)) the air in the bread still had some residual pressure left within its pores to expand further, albeit more slowly. Modocc (talk) 10:07, 2 December 2012 (UTC)

I'm rather skeptical that instantly rising, edible bread in a tube actually exists. If it does, it should be sold to consumers, where it would be a party hit. StuRat (talk) 18:50, 2 December 2012 (UTC)

Seeing a clever illusionist live can be very impressive. Seeing a film or video of anyone seeming to be an illusionist just makes me sceptical. HiLo48 (talk) 00:04, 3 December 2012 (UTC)

I call "camera trick" (although it's more properly CGI rather than old school in-camera trickery). I think I can see the fuzzy reflection of the entire loaf in the chrome table-top in front of the magician...which would definitely indicate camera trickery. The fact that the camera 'jumps' forward and stops floating around like it was before just as he starts pulling on the bread seems significant. Minimizing camera motion makes graphics trickery much easier...to the point where it's actually easier to put the camera on a tripod and add in 'fake' camera sway after you've done the actual trickery parts of the editing. The very uniformly red background of the lower half of the shot would greatly help if one were doing "blue screen" kinds of computer graphics effects here. SteveBaker (talk) 14:14, 3 December 2012 (UTC)

The red background, the general setup (such as there being no audience is in the shot as he performs it) and the camera work is conducive to graphics trickery, thus I do agree that's almost certainly how it was done, even though I can only see what appears to be primarily his arm and hand in the reflection. In any case, the OP did ask if making the bread appear in one's hand as a magic trick, is possible, and I think it can be done if the bread is spongy and elastic, along with strategically placed cavities within it if necessary to allow it to be adequately compressed. -Modocc (talk) 16:54, 4 December 2012 (UTC)

How should "望闻问切" in Traditional Chinese medicine be translated into English?

Seemed this is not covered in the English article, and the Chinese article zh:中医诊断学 which this term redirects does not have an English correspondent--Inspector (talk) 13:41, 1 December 2012 (UTC)

You might want to delete this and repost it at the language desk instead. μηδείς (talk) 17:39, 1 December 2012 (UTC)

Google Translate renders it as "look and smell". Looie496 (talk) 17:49, 1 December 2012 (UTC)

This is an instance where I would not trust a machine-translation at face value. Reading many of our articles, I found a citation in our Medical Diagnosis article. These characters translate literally as "look, smell, ask, cut." I also found this phrase, commonly coincident with the other characters: 中医四法, which translates as "the four methods of medical diagnosis." Elsewhere, I have seen these enumerated: "looking, listening, questioning the patient, and checking the pulse." The exact methods vary from source to source. It is my opinion that "check the pulse" is a rather euphemistic translation, now that bloodletting has fallen out of favor, but as I read 切, I interpret "make a giant carving." I'm not fluent in any of these languages, though. It appears that these are general descriptions of "methodology," and not a description of an exact procedure. Sometimes that last one is called "cutting" or "incision." Now, if I could only find out which simplified Chinese characters represent germ theory of disease, I could work on bridging the cultural- and linguistic- barrier for the betterment of medical practice everywhere! In all seriousness, is there even such a concept in traditional Chinese medicine? I have not been able to find any reference to the idea - the fact - that for at least some ailments, we have actually ascertained the root-cause to a specific infectious microbe. Our article on traditional Chinese medicine discusses folklore conceptions of disease, but makes no mention of any attempt to consolidating that world-view with new factual evidence. Nimur (talk) 20:21, 1 December 2012 (UTC)

(*facepalm*) Guys/gals, the Chinese article tells you exactly what 望闻问切 means. That's probably why the OP linked to it--he understands the article, but doesn't know how to properly translate the name into English.

Quoting from the Chinese article:

In Traditional Chinese Medicine, the "four methods" is the collective name for basic methods of medical checkup, including "sight checkup", "listen/smell checkup", "asking checkup", "feeling checkup", hence 望闻问切. 望means observing the patient's bodily condition, including facial color, tongue, etc; 闻means listening to the patient talk, cough and breathe, and smelling his breath or body for abnormal odors; 问means asking the patient about his condition, disease history, etc; 切means using the hand to check the pulse or press the abdomen to see if anything is unusual. Through the "four methods", the checkup reveals all types of symptoms and characteristics, for the purpose of understanding the disease's origin, character, and relationship with the internal organs, to provide a sufficient basis for diagnosis.

切cannot possibly mean bloodletting, because that's not a diagnostic method, there's no evidence that anybody used bloodletting in TCM, and 切 has numerous meanings depending on context, and the one for "cut" has a different pronunciation than the one for "ascertain/correspond". That article on 切土 is Japanese, not Chinese, and as the article says, 切土 means cutting through a hill to build a flat path through it. I don't know what the corresponding word is in English, but again, 切 has a different pronunciation in this context than in 望闻问切. The Chinese term for the germ theory of disease is 疾病细菌学说 or 疾病细菌说 (literally "disease germ theory"). As for why TCM doesn't mention it, it's because the germ theory of disease is an 19th century European invention while TCM is an ancient pseudoscience. If TCM made any sense at all, it wouldn't be "alternative medicine" (read: utter bullshit); it would be Western medicine (西医). --140.180.249.151 (talk) 20:25, 2 December 2012 (UTC)

For the record, I'm well aware that Kanji characters can mean totally different things in Chinese or Japanese context. As I mentioned, my interpretation is colored by my prior experience; I recognized a kanji and knew it from somewhere else. Any fluent reader would make the same connection, consciously or otherwise. The words may be pronounced differently, but the language is structured such that these meanings have an implicit connection. How can we ignore that detail when translating? We have to make a tradeoff between clarity and correctness. As you are undoubtedly aware, it is very difficult to "correctly" translate Chinese to English without losing a lot of nuance and context. If you translate the phrase literally, you produce a disjointed sequence of English nouns. If you translate semantically, you lose the context specificity. In both cases, you lose the double-entendre impact of each ideogram. English has a concept of homonyms, I do not believe that concept captures the subtlety of a shared ideogram or a tonal shift. As proof, consider this: Lion-Eating Poet in the Stone Den. In its original form, it's a clever poem. In English, it's formless nonsense that doesn't really satisfy any poetic criteria. Chinese, as a language, is so structurally different from English that it is not possible to directly translate; much effort is needed to tease out the meaning; which is why (as I prefaced my earlier comment) a machine translation is often inappropriate. Thank you, 140.180.249,151, for your insights into the subject. Sorry that you feel the need to face-palm yourself. I do not agree that traditional medicine necessarily refers exclusively to that portion of folklore tradition that eschews factual evidence. Of course, much traditional medicine is clearly pseudoscience. But it seems to be an unfortunate hijacking of the terminology to define "traditional" medicine as "anything and everything that necessarily excludes real, factual knowledge." Nimur (talk) 05:18, 3 December 2012 (UTC)

Why in some countries, HIV\Hepatitis C tests are after 2 months and in others 3 months (of suspicious contact) ?

Why in some countries, HIV\Hepatitis C tests are after 2 months and in others 3 months (of suspicious contact) ? Thanks. 79.182.153.70 (talk) 22:32, 1 December 2012 (UTC)

Two or three months after what? Can you clarify and give some context for your question? RudolfRed (talk) 22:38, 1 December 2012 (UTC)

i did that (read the header again). — Preceding unsigned comment added by 79.182.153.70 (talk) 23:06, 1 December 2012 (UTC)

I think the short answer is that such decisions are driven by logistical considerations, after a scientifically-reasonable range of options has been established. For both HIV/AIDS and Hepatitis C, seroconversion occurs 1-2 months after onset of infection (i.e. an exposure resulting in infection). Examples of evidence for this are here and here, more specifically for HCV PMID. So, testing at 2-3 months will detect most seroconversions, though some have suggested testing at 6 months as well to avoid missing late seroconversions (this is exceedingly uncommon with current tests). -- Scray (talk) 05:38, 2 December 2012 (UTC)

More data for HIV PMID 20846033 and HCV PMID 22715213 and PMID 11264728. -- Scray (talk) 05:55, 2 December 2012 (UTC)