Wikipedia:Reference desk/Archives/Science/2013 January 5

= January 5 =

"Acute in age"
I recently woke up with pain in my finger. When I went to the doctor and had an x-ray, I learned that I had somehow broken it (probably overnight on the 31st). The doctor printed up a little document explaining what happened, but I didn't look at it until I had already left (because he explained very well verbally to me). On the document, the text "fracture radiographically appears acute in age" appears. What does the phrase "acute in age" mean? Google is of no help. Thanks! -- Tohler (talk) 00:03, 5 January 2013 (UTC)


 * Well, "acute injury" means that it stems from a single traumatic event, rather than chronic (stemming from some long-term cause). -- Finlay McWalterჷTalk 00:07, 5 January 2013 (UTC)


 * See also the paragraph of Acute (medicine) beginning "The acute phase of an injury is the period of time in between when the injury is sustained, and the beginning of the sub-acute phase." -- Finlay McWalterჷTalk 00:11, 5 January 2013 (UTC)


 * In other words, "acute in age" = "recent injury". 24.23.196.85 (talk) 04:34, 5 January 2013 (UTC)
 * Why be direct when they can be obscure? Like the lawyer who frets over your not writing a will, warning you that you could die intestate. ←Baseball Bugs What's up, Doc? carrots→ 05:56, 5 January 2013 (UTC)
 * Often laypeople get the urge to denigrate technical terminology, saying it could have been replaced with some lay terminology that doesn't actually mean the same precise thing. Maybe some of the above comments are an example of that. It looks to me like "acute in age" means "still in the acute stage, not yet in the sub-acute stage", in which case "age" refers to how far along it is in the expected sequence, not how recent in clock or calendar time it is (even though those would be imperfectly correlated). Note that the doctor was not being obscure, since he explained it well orally to the OP. Duoduoduo (talk) 14:07, 5 January 2013 (UTC)
 * "Acute" as a word means "sharp". In fact, it appears that the term "acute" is used in at least two somewhat different ways in the medical community. Kind of like how football uses the term "safety". ←Baseball Bugs What's up, Doc? carrots→ 16:00, 5 January 2013 (UTC)
 * Three actually, given there's "player safety" (prevention of bodily injury) as well as the positions and the scoring method. -- Jayron  32  19:13, 5 January 2013 (UTC)
 * Yes. As in baseball, where there at least three usages of the term "hit" that come to mind. Or this fanciful definition of "rock": "To cause someone or something to swing or sway, by hitting them with it." ←Baseball Bugs What's up, Doc? carrots→ 20:45, 5 January 2013 (UTC)
 * I have no quarrel with "acute in age", now that I understand it; but I would like to know how "bilateral upper extremities" is better than "both arms", or why "infant is status post negative rule out sepsis" shouldn't be reworded. —Tamfang (talk) 06:13, 1 July 2013 (UTC)

Maybe "acute in age" was a transcription error for "acute stage". Duoduoduo (talk) 13:57, 6 January 2013 (UTC)
 * I am not quite so sure of the reason for this struggle to explain away "acute in age". I went to the emergency room thinking I had broken my big toe.  The doctor returned and said, yes, the toe was broken, and started manipulating the second one.  I complained he had the wrong toe.  Then, after looking at the exray again, he realises it was an old, healed break.  Obviously he could tell on looking that the break was no longer acute in age. μηδείς (talk) 17:09, 6 January 2013 (UTC)

Science Olympiad
my teacher is not able to help me with these because we don't have any astronomy class in my school. I got stuck on number 27, 14, 15. see here. anskey, I got the answers but that doesn't mean I know how to do them. I need help on show me how to do it like what formula do I need to use, what can I tell from the result after calculating the formula, how do I interpret that? This is not homework as obvious.174.20.15.246 (talk) 01:27, 5 January 2013 (UTC)
 * Number 27 tells you the period (25 days) and apparent magnitude (mean = +24.9) of a Cepheid variable. Use the equation at Classical Cepheid variable to calculate the absolute magnitude from the period, then the equation here to calculate the distance.  -- Jayron  32  01:38, 5 January 2013 (UTC)
 * Alright got it! How about 14, 15?174.20.15.246 (talk) 02:05, 5 January 2013 (UTC)


 * 14 and 15 can be solved with the Tully-Fisher relation. --99.227.0.168 (talk) 07:25, 5 January 2013 (UTC)
 * I still don't get it. Let take a look at the problem. "Galaxies X and Y appear equally bright in the night sky. When a radio spectra of both galaxies are taken, the 21cm line of galaxy X is twice as wide as that of galaxy Y." So the key answer tells me the correct answer is galaxy X. Which means galaxy X must be further from Earth than galaxy Y so that means they have the same apparent magnitude but X has higher absolute luminosity (related to absolute magnitude). I have looked through Tully–Fisher relation but unable to find out any formula to use to figure out anything. Can someone please give me an example calculation?174.20.15.246 (talk) 07:42, 6 January 2013 (UTC)


 * From the linked article "roughly speaking, luminosity is proportional to velocity to the fourth power." Dauto (talk) 15:54, 6 January 2013 (UTC)

Lever frame
On British railroads, the levers in a lever frame are (well, used to be) color-coded as follows: Red -- Home signal; Yellow -- Distant signal; Black -- Railroad switch; Blue -- Facing point lock (locks corresponding switch in place); Brown -- Level crossing gate; White -- Spare. Does anyone know what were the corresponding color-coding conventions in France and Germany in the 1940s? Thanks in advance! 24.23.196.85 (talk) 05:26, 5 January 2013 (UTC)

Any ideas? Oh well, I guess I can just use the British color-coding in the signal box scene -- nobody's likely to notice, right? 24.23.196.85 (talk) 05:47, 6 January 2013 (UTC)


 * (Sorry to be so slow in getting you an answer...)
 * This page looks like it might be of help - the photos of the interiors of signal boxes in France look VERY different - not just the color coding. The section on german boxes says that the entire signalling system was different - and goes into the color coding some. SteveBaker (talk) 20:53, 8 January 2013 (UTC)


 * Thanks! I'm writing a scene where the Maquis are trying to switch the tracks at a junction in order to put a German ammo train on a siding rigged with explosives and blow it up -- so this is actually more info than I really needed, because they definitely won't be using the signal apparatus (in fact, the reason I asked was to see how they could switch the tracks without also changing the signal).  And the part about the German signal box will come in handy near the end of the book, where the same Maquis team (which has parachuted into the Hurtgen Forest on a special mission) has to stop a prisoner train (by flipping the signal to "Stop") so they can take it over and infiltrate a secret German underground chemical plant.  :-) 24.23.196.85 (talk) 03:06, 9 January 2013 (UTC)

Recession
Do you think the world recession is affecting science and engineering? — Preceding unsigned comment added by 90.219.64.4 (talk) 14:35, 5 January 2013 (UTC)


 * Maybe in cases where research and development budgets are being cut. In my company, R&D is actually expanding. Companies figure R&D is vital for future competitive advantage. ←Baseball Bugs What's up, Doc? carrots→ 15:54, 5 January 2013 (UTC)


 * Yes, smart companies may actually increase R&D during a recession, as the business cycle is such that they might have new products ready to go just when the next boom starts. StuRat (talk) 21:18, 5 January 2013 (UTC)
 * Well those R&D are not actually for the sake of science, just for the profit they will be making. No profit = no R&D. Hard to blame them, everyone wants to make money... That's why they are companies not scientists. It's true that those new products from the companies may benefit the society later on. But the researches just for the sake of science without caring about its value must be declining because people don't interest in it especially in hard time. An example would be NASA.174.20.15.246 (talk) 07:21, 6 January 2013 (UTC)
 * Regarding science (engineering may be quite different): I confess I don't really know, but I haven't heard of any funding cuts to research in Australia. I'm doing a PhD on a scholarship, so I might have heard if anything was going down (I get to hear some of the goss, not the informed analysis). Government funding for research seems to be relatively recession-proof, since the government doesn't have to respond directly to an economic shockwave. It does have to take the economy into account, but it can take its time, unlike a commercial enterprise. It isn't, after all, in direct competition with a rival government trying to move in on its turf, at least not usually. IBE (talk) 19:14, 6 January 2013 (UTC)
 * Whenever the economy is bad, it's true that the government is not directly affected but it does affect the government somewhat. Let say everyone is making less money so that's mean the government will get less money from tax. When they have less money, there is no way they can keep up funding any research at the cost before. There got to be some cuts in the government spending or maybe they will cut a bit of everything.174.20.15.246 (talk) 20:25, 6 January 2013 (UTC)
 * This can't be totally wrong, but there's a lot more. Australia spent a lot of money trying to keep itself out of recession, as described here. I'm not an economist, but governments work slightly differently to corporations, and the money supply isn't a given. IBE (talk) 23:43, 6 January 2013 (UTC)
 * What the article linked by BeenEmotional doesn't spell out is how the Australian Government was able to spend this vast amount of money (which incidentally was largely wasted on projects with little or no economic return and lots of corruption) is that they had two sources: 1) a large surplus left over from when they took over from the opposition party, and 2) they borrowed vast amounts from China. This is directly equivalent to a private company or private individual on hard times spending their bank savings down at the casino, and then borrowing from a bank to continue down at the casino.  In other words, short term, the amount of money about is proportional to the stupidity of politicians, and in the long term the crunch will come.  The leader in this stupidity, Prime Minister Rudd, got the sack as he was completely on the nose.  ADisgustedAssie 124.178.183.98 (talk) 01:28, 9 January 2013 (UTC)

sleeping with makeup on -- does your skin really need the oxygen?
I am transgender, but I also study biochemistry, so I'm always skeptical of the skincare industry. I like to leave makeup on because I can still wake up looking female (especially if I am sleeping with someone) but I wonder (despite what I read on the internet) whether this is really all that bad. Your epidermis isn't really alive, right, and all the alive parts get enough oxygen from their blood?

Not a request for medical advice, more of an inquiry of whether there are skin cells (that are alive) that need oxygen from the exterior. 72.229.155.79 (talk) 18:43, 5 January 2013 (UTC)


 * No, they don't need oxygen, or you couldn't wear a bandage for very long. The problem is that some chemicals will irritate or will block pores if left on too long. You can see if the product has a tollfree number to call for advice. μηδείς (talk) 18:53, 5 January 2013 (UTC)


 * What are the consequences of blocked pores? To me it seems it would just stop sweat. 72.229.155.79 (talk) 19:19, 5 January 2013 (UTC)


 * Googling the issue, it seems that if the oil/sebum oxidises that it would polymerise and cause blackheads/whiteheads? Would foundation do the same? Trying to get a scientific perspective, I am SO skeptical of the skincare industry and cleansers. I use generic moisturisers, not brand-name ones. 72.229.155.79 (talk) 19:22, 5 January 2013 (UTC)


 * Blocking pores doesn't stop sweat getting out (I can sweat quite happily through full makeup), but it does stop the natural progression of sebum. It's possible then that the pores can get infected and lead to comedones and blackheads. --TammyMoet (talk) 19:26, 5 January 2013 (UTC)


 * Yes, and sebaceous cysts are quite nasty. Depending on where you are located there are probably cosmetologists, dermatologists, and other crossdressers who can help.  NYC has no end of such resources. μηδείς (talk) 19:38, 5 January 2013 (UTC)


 * Thick enough make-up can stop sweat, and, if it covers a large portion of the body, this causes thermal distress and possible heat-stroke by denying the body the ability to cool itself. Mythbusters did an episode on this, where they painted one of them gold.  Presumably your make-up isn't that thick or widespread.  Also, skin does need access to air, not so much for oxygen for your cells as to dry it off.  Skin under bandages eventually gets white and puffy, with the white from lack of sunlight and the puffy from the inability to air out.   StuRat (talk) 21:11, 5 January 2013 (UTC)


 * Jill Masterson in Goldfinger supposedly died of "epidermal suffocation" by having her entire body covered in gold paint. She supposedly would have survived if the culprit had left only a small circle at the base of her spine unpainted.  How scientifically accurate this is, I can only guess.  --   Jack of Oz   [Talk]  01:59, 6 January 2013 (UTC)


 * Probably exactly as accurate as anything else in a James Bond film... -- Jayron  32  02:08, 6 January 2013 (UTC)


 * Well, according to Mythbusters, there was one scientifically accurate thing in Goldfinger -- the tire slashers on 007's Austin-Martin. 24.23.196.85 (talk) 08:05, 6 January 2013 (UTC)


 * Even the blind dog finds the tree once in a while. -- Jayron  32  18:30, 6 January 2013 (UTC)

Sintering Metal and Ceramic together
Would it be possible to take a powdered ceramic like glass and some powdered metal, mix them finely, and sinter it into a single piece? If so, what kinds of properties would it have, and would such a thing have a name? If not, then what would happen if you tried it? Rabuve (talk) 20:55, 5 January 2013 (UTC)
 * The Wikipedia article on cermet covers some of it, and more information can be found with a Google search for "cermet sintering. It seems to be a fairly common technique for manufacturing cermets. WegianWarrior (talk) 21:12, 5 January 2013 (UTC)
 * If ceramics are metal oxides, and the exposed surfaces of any metal object oxidize to some extent under normal conditions, isn't every metal object, to some extent, a metal and a ceramic? Or perhaps this is very silly was of looking at things and missing out on some important point.  DRosenbach  ( Talk 06:22, 7 January 2013 (UTC)

Pineapple pee
I ate two large cans on pineapple yesterday, and today my urine smells like pineapple. So, is there some characteristic, fragrant component of pineapple that comes through, unchanged, in urine, just like in asparagus ? StuRat (talk) 21:38, 5 January 2013 (UTC)


 * There is an enzyme in pineapples that is known as bromelain. Some people believe that it offers urinary, digestive and anti-inflammatory effects. I doubt that it's the whole story behind the smell, but it could be a start. EricEnfermero  Howdy! 01:49, 6 January 2013 (UTC)


 * Thanks for the info on bromelain. StuRat (talk) 02:30, 6 January 2013 (UTC)


 * Not a single one of these is a reliable source but it at least shows that your experience is not singular. -- Jayron  32  01:56, 6 January 2013 (UTC)


 * In my searching, ethyl butanoate appeared most frequently (and our article even mentions that the compound smells like pineapple). In the medical literature  prominently mentions a similar compound, ethyl 2-methyl butanoate.  Not sure about absorption and urinary excretion, but it seems plausible.  -- Scray (talk) 04:29, 6 January 2013 (UTC)