Wikipedia:Reference desk/Archives/Science/2008 September 26
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September 26
[edit]"hurricane" in France
[edit]Hi. I think I read somewhere that a "hurricane", most likely an extratropical cyclone, struck France causing $88 billion in damage sometime in the late 20th century, second costliest worldwide only to Katrina. Also, is there an article on this? The global tropical cyclones track image, a featured picture, which does not distinguish between extratropical and tropical systems, shows at least one category one hurricane approaching France. Also, is there an article for the hurricane-strength cyclones that struck Britain I think in 1990 (and killed Emily Macdonald), and recieved "names"? Also, does anyone know is there an online database where I can search, for example, the last time (year, name) that a tropical cyclone of x intensity approached within x km of a specified location, etc? Thanks. ~AH1(TCU) 01:54, 26 September 2008 (UTC)
- Wikipedia has a pretty extensive catalog of tropical cyclones:
- -- MacAddct1984 (talk • contribs) 02:17, 26 September 2008 (UTC)
- The French one was in December 99, just 1 or 2 days after Christmas. I cannot remember the name of the cyclone, though, sorry --Lgriot (talk) 02:28, 26 September 2008 (UTC)
- I found it!: "The second storm event occurred on December 26. It was caused by a low named "Lothar", and left a trail of destruction from northwestern France to southern Germany and Switzerland." full text at: [1] . We also have an article: Lothar_(Storm) --Lgriot (talk) 02:37, 26 September 2008 (UTC)
- Hurricanes have to be tropical cyclones (or sub-tropical cyclones, as the definition was expanded recently). Extratropical cyclones, not matter how strong, cannot be hurricanes. See Cyclone, specifically Extratropical cyclone, Subtropical cyclone, and Tropical cyclone. Plasticup T/C 03:35, 26 September 2008 (UTC)
- Following the external links in the Lothar article, I find that it caused 5.0 billion
Euros damage - less than the 1990 storms which hit France. So the "second costliest worldwide only to Katrina" part cannot be correct. Hurricane Katrina caused about $100 billion damage. Rmhermen (talk) 13:25, 27 September 2008 (UTC)
ACCA
[edit]Hello I want the free Notes for ACCA if some help me i will be very thenkfulPDF). Also what is the salary given to ACCA with one year experience in UK(in digits please) —Preceding unsigned comment added by 119.154.29.138 (talk) 02:39, 26 September 2008 (UTC)
- Association of Chartered Certified Accountants and Chartered Certified Accountant may be of some help. SteveBaker (talk) 03:42, 26 September 2008 (UTC)
Kinetic Energy of Helium
[edit]Yup, I'm doing homework. I thought I'd done the question right, but can't get my online homework board to accept my answer. To find the total kinetic energy of 2.4 kg He at 298.15 K, I used the formula KE (avg) = (3/2)RT, then multiplied this by the number of moles.
So: (3/2)(8.314 J/mol*K)(298.15K) = 3718.2 J/mol
(2.4 kg He)(1000g He/1 kg He)(1 mol He/4.003 g He) = 599.6 mol He
(599.6 mol He)(3718.2 J/mol He) = 2.229E6 J
There is a second part to this problem, but I thought I'd see if I was doing something incorrectly in this first part, or if I am at least right to this point? Any pointers to my approach and setup of this problem would be appreciated.
166.70.30.42 (talk) 07:19, 26 September 2008 (UTC)Andy
Nevermind...I figured it out. Damned significant figures get me every time... 166.70.30.42 (talk) 07:40, 26 September 2008 (UTC)Andy
bird nomenclature / indie rock lyric question
[edit]Joanna Newsom is a (really hot) singer who writes rambling 11-minute songs bursting with precious avian references. One memorable opus begins, "The meadowlark and the chim-choo-ree and the sparrow set to the sky in a flying spree, for the sport over the pharaoh". What the heck is a chim-choo-ree? I searched the encyclopedia for a bird by that name but found only the Mary Poppins song.--The Fat Man Who Never Came Back (talk) 07:52, 26 September 2008 (UTC)
- ArthurMag has an article on Joanna Newsom where it is suggested that she probably derived "chim-choo-ree" from Mary Poppins. --Bruce1eetalk 14:13, 26 September 2008 (UTC)
- Thanks. That's a good reference--funny too: "Meadowlarks and sparrows are songbirds, of course, but the chim-choo-ree, as far as I can tell, is probably an outgrowth of watching Mary Poppins too many times." But isn't the song "Chim Chim Cher-ee" about chimneys and not about birds? Ms. Newsom is an odd duck. Anyway, sorry to bother the Science desk with this pop culture rubbish; I imagined that a chim-choo-ree was some sort of archaic slang for a specific songbird.--The Fat Man Who Never Came Back (talk) 16:03, 26 September 2008 (UTC)
Severity of Decelleration Required to Cause Traumatic Brain Injury
[edit]I've seen that rapid decceleration can cause diffuse brain injury in numerous places, and that this can occur/ is likely to occur in auto accidents. However, I have never seen it mentioned exactly how severe the accident needs to be, nor the neccesary ammount of decceleration. So, this is my question: what level of acceleration is neccesary to cause brain injury, is coming to a quick stop without impact in a motor vehicle capable of causing brain injury, and (pending upon the answers to the first two) how is it that proffessional race car drivers/astronauts/sky divers/etc. do not sustain injury for these reasons? Thank you in advance for any help. Phoenix1177 (talk) 13:35, 26 September 2008 (UTC)
- Hmm, well internal bleeding is common from deceleration in high speed accidents. Since this can injure your organs, this would presumably apply to your brain as well. I would assume it doesn't affect (or is it effect?) the people you listed because they don't actually decelerate all that quickly. If a professional driver were to slam into a wall and go from 150mph to 0 in no seconds flat, internal bleeding would probably be a major concern (or the least of their worries?). -- MacAddct1984 (talk • contribs) 13:54, 26 September 2008 (UTC)
- Thank you for your reply. A large part of my question stems from the fact that someone wrecking into a wall at 60 mph has a moderate chance of brain injury, whilst it doesn't seem common sensical that someone going 60 mph and slamming on their brakes would have equal chances(mainly because people slam on their brakes a good deal and don't seem to sustain such injury) So, I figure that either those extra few miliseconds of stopping time and meters of distance with the brakes are a mitigating factor, or that most people involved in high speed action should be at high risk for brain injury. [the case for sky divers is probably unreasonable, but with race car drivers it would seem somewhat more logical] Phoenix1177 (talk) 14:07, 26 September 2008 (UTC)
- If you're not in a race car, your braking and turning maneuvers won't be much higher than 1g. -- Coneslayer (talk) 14:27, 26 September 2008 (UTC)
- If you hit the brakes full on at any speed the reduction in speed will be not even in the same league as a crash. If i'm correct I think a big thing is the 'g-force' you go under in a crash. There is G-force#Human_tolerance_to_g-force that may be of interest. In particular the 'involuntary' section showing crashes. A vehicle braking will get some g but it won't be anywhere near that of a crash. The more 'time' that can be introduced into the deccelaration the better, that's the purpose of crumple zones and airbags and etc. etc. 194.221.133.226 (talk) 14:21, 26 September 2008 (UTC)
- This study demonstrated deformation of brain tissue during deceleration of 20–30 m/s2, with the neck unprotected. Allowing the neck to pivot freely increases the strain just above the base of the brain where the brain is mostly strongly adherent to the surrounding bone. Professional racing drivers and astronauts wear neck protection to prevent whiplash injuries. This also helps to reduce torsion of the brain at its base. Axl ¤ [Talk] 14:34, 26 September 2008 (UTC)
- More specifically, a basilar skull fracture is the danger when your body stops faster than your head does. The bone sutures can split and tear open the sacs holding in your brain's precious bodily fluids. --Sean 16:54, 26 September 2008 (UTC)
- This study demonstrated deformation of brain tissue during deceleration of 20–30 m/s2, with the neck unprotected. Allowing the neck to pivot freely increases the strain just above the base of the brain where the brain is mostly strongly adherent to the surrounding bone. Professional racing drivers and astronauts wear neck protection to prevent whiplash injuries. This also helps to reduce torsion of the brain at its base. Axl ¤ [Talk] 14:34, 26 September 2008 (UTC)
- You also have to worry about your head hitting the windshield/steering wheel and your chest hitting the steering column (wear your seatbelts!). Although, I did go on a call to a car accident where the patient had a collapsed lung, even though the airbag deployed... -- MacAddct1984 (talk • contribs) 17:45, 26 September 2008 (UTC)
Plant identification questions (yew and juniper)
[edit]I would like some help identifying some plants. I have some yew shrubbery and a juniper tree in my yard. I would like to know more specifically what type of yew and juniper I have. I live in Richmond, Virginia. The juniper is about 15 feet tall, and in a general cone shape. My brother believes it is Juniperus communis, but we weren't entirely sure how that differed from Juniperus virginiana. My concern is the berries. The berries are not round, but instead are sort of spikey. What sort of things can I look at to identify the type of juniper? Any details I could provide online that could help someone identify it? As for the yew, my brother believes it is a Taxus cuspidata, but I wasn't sure how that differed from Taxus baccata. Again, what sort of things should I look for to tell what type of yew it is?
I could provide photos if necessary, but I'd also like to learn what to look for myself. Thanks!-Andrew c [talk] 16:18, 26 September 2008 (UTC)
Evolution of axon membranes
[edit]We were studying the membranes of nerve axons today in biology and it confused me as to how such a system could evolve? We were studying different channel proteins and carrier proteins etc. Anyway, wouldn't any organism without such pumps like sodium-potassium pumps die? How else could organisms without proteins to carry out active transport survive? It seems unlikely that an entire membrane could evolve in one generation of a cell. I'm not trying to encourage creationism or anything, I do believe in evolution, it's just a bit confusing.
As a second kind of follow on question, are there any organisms that survive or is it at all possible for an organism to form without adenosine triphosphate mechanisms? Thanks a lot :)
—Cyclonenim (talk · contribs · email) 17:18, 26 September 2008 (UTC)
- "It seems unlikely that an entire membrane could evolve in one generation of a cell" - that's correct and as sure as I am that my username is Seans_Potato_Business, I don't believe it evolved over the generation of a single cell. There's not telling how each of the proteins involved (you can look for clues by checking sequence homology among genes and among organisms) but each gene and gene-product may have started off as something else. It's nor necessary (nor possible?) to known or understand each evolutionary step which occured. ----Seans Potato Business 17:36, 26 September 2008 (UTC)
- I do appreciate that, it's not really a simple discussion. My point was, however, that wouldn't an organism die without just one type of these intrinsic proteins? If it didn't evolve all at once, how could it come into existence at all? —Cyclonenim (talk · contribs · email) 18:10, 26 September 2008 (UTC)
- All organisms require ATP or GTP via biochemical respiration. However this paper suggests that bacterial motility may occur through a different intermediate in oxidative phosphorylation. Axl ¤ [Talk] 18:11, 26 September 2008 (UTC)
- A modern organism might die without one protein from the pool. However this is no reason to suppose that an evolutionary ancestor would die without that protein. Axl ¤ [Talk] 18:14, 26 September 2008 (UTC)
- It is noted that a wide range of living things have similar needs when it comes intracellular K and Na levels. As you are apparently are aware, much modern life maintains the right ranges by actively pumping Na and K against the natural gradient. The easiest explanation for how that situation might have evolved is if there was some very primitive progenitor that lived in an environment that didn't need pumping, i.e. to assume that once upon a time the external Na and K levels matched the internal levels we have today. The evolution of active pumping would allow a cell to escape that environment, but the existence of active pumping wouldn't be necessary to live there. Though I don't think it tells the whole story, the chemistry of the oceans themselves were radically different early in life's history (high Fe(II), lower Na, negligible O), so it certainly plausible that life initially began under very different environmental constraints than exist today. Dragons flight (talk) 18:26, 26 September 2008 (UTC)
- Another way to look at it is this: It is possible that a proto-organism lived at equilibrium with the salt water environment, but that evolution of channels capable of separating charge across the membrane would be extraordinarily beneficial and allow the descendents of that proto-organism to thrive. The neuronal axon is an extremely specialized situation that has evolved over many millions of years. However, other cell types in the body also use gradients for transporting all sorts of things across the membrane, which you might imagine would be advantageous to a single celled organism in the primordial soup. Also, the ability to build up charge on the surface and discharge it upon some stimulus could be considered as a possible form of primordial warfare. There are plenty of explanations for how a complex adaptation like the neuronal cell membrane could evolve in small steps, each of which could be advantageous to the given organism in its particular context, without calling forth the "irreducible complexity" argument (i.e. "It seems unlikely that an entire membrane could evolve in one generation of a cell.") favored by the intelligent design crowd. By the way, you don't need to "believe" in evolution. You just have to understand how it is actually theorized to work, think up some testable hypotheses, and look for ways to confirm or refute them! Have fun. Medical geneticist (talk) 22:45, 26 September 2008 (UTC)
Making gold
[edit]Is it theoretically possible to make gold out of common atoms like hydrogen or carbon? Is there any serious scientific investigation going on in this field?Mr.K. (talk) 18:27, 26 September 2008 (UTC)
- See Synthesis of noble metals#Gold -- MacAddct1984 (talk • contribs) 18:35, 26 September 2008 (UTC)
- Theoretically all heavy elements are derived from lighter elements (see Supernova nucleosynthesis). I'm not sure if something as light as hydrogen or carbon could be made into something as heavy as gold in a meaningful way with current technology (keep in mind the links above are just about going from specifically Mercury to Gold, which is just a proton difference). But theoretically it's possible—esp. if you were using fusion technology. But it's not likely ever a worthwhile replacement to mining. --98.217.8.46 (talk) 22:13, 26 September 2008 (UTC)
- I can't help but wonder: what worth would gold have if you could make it in your cellar? hydnjo talk 23:22, 26 September 2008 (UTC)
- It would still be useful for electrical contacts and it would still look pretty so would be used for cheap jewellery, so it would have some value. It would lose most of its value, though. --Tango (talk) 23:30, 26 September 2008 (UTC)
- For sure gold has practical value. I was just musing about the non-practical value should gold become abundantly available as was suggested by Mr.K. There would be some advantage I'm sure in using gold foil in place of aluminum foil for some everyday applications ;) hydnjo talk 01:36, 27 September 2008 (UTC)
- Beisides that, hydnjo, if I could make in my cellar that would not disturb the market price of gold. It would only improve my financial situation. Mr.K. (talk) 10:54, 27 September 2008 (UTC)
- C'mon now Mr.K., surely you'd share your recipe with us and you know what blabber mouths we are. -hydnjo talk 12:33, 27 September 2008 (UTC)
- The amusing thing is, Mr. K, if you had the technology to make gold out of carbon, you'd make more money licensing that than you'd ever make by producing gold. --98.217.8.46 (talk) 14:34, 27 September 2008 (UTC)
- By selling the gold you make in your cellar you would depress the price of gold - it's simple supply and demand. If you were disciplined and only made a small amount of gold, the affect would be negligible, but if you tried to make massive amounts (something in the region of hundreds of tonnes, I'd expect) you could cause a massive crash in the price of gold. --Tango (talk) 15:22, 27 September 2008 (UTC)
- I think he means if everyone could make gold in their cellars. — DanielLC 16:40, 27 September 2008 (UTC)
- Also, that scenario reminds me of an episode of The Twilight Zone (specifically, the end). — DanielLC 16:42, 27 September 2008 (UTC)
- Unless your particle accelerator gets free electricity, the energy input would cost orders of magnitude more than the gold would be worth. Cheaper, but still not cost effective, to extract the gold dissolved in the ocean. More cost effective to rvcover gold from electrical contacts in trashed electronic equipment. Edison (talk) 19:33, 29 September 2008 (UTC)
Extremely deadly tranquillisers?
[edit]I was watching The Lost World and one of the characters mentioned that if someone accidentally shot themselves in the foot with one of their tranqs, it would kill them instantly. Are there any real tranqs that are this deadly, where a single shot to the foot would instantly kill a man? ScienceApe (talk) 20:04, 26 September 2008 (UTC)
- Tranquillisers don't take effect instantly. They take seconds or minutes to take effect. The dose of tranquilliser determines the risk of death. If the tranquilliser is intended to sedate an elephant, it could well kill a person. Axl ¤ [Talk] 20:22, 26 September 2008 (UTC)
- Well in that movie it wasn't actually a tranquilizer, it was a refined neuro toxin derived from the venom of a
conch shellcone snail, but I don't know how realistic this is (In fact I doubt it, I don't see how a shot in the foot could kill you that quickly before it has time to reach your heart, lungs, or brain). -- Mad031683 (talk) 16:45, 29 September 2008 (UTC)- It was apparently the cone snail, not the conch shell. My memory of the book describes a woman being stung by one, taking a few steps and falling over dead. The article seems to support a fairly rapid death from the sting of a large cone snail, but nowhere near as rapid as described in the book/movie. I'd buy death in a few seconds(as soon as the toxin reached the brain) but not so fast you don't even realize you shot yourself. -- Mad031683 (talk) 16:57, 29 September 2008 (UTC)
- Well in that movie it wasn't actually a tranquilizer, it was a refined neuro toxin derived from the venom of a
Tango, so you siad the sky color is not always the atmosphere on the top?? Well, Venus sky is orange-scarlet or coral seen from the surface because the orange-rd smog. Wouldn't the middle of cloud layers be yellow or yellow-orange. Does anybody know what's the color of Venus' sky above the cloud-tops, because Venus have 3 main layers of clouds.--57Freeways 23:20, 26 September 2008 (UTC)
- A good example of a planet with a different coloured sky from the inside than the atmosphere appears from the outside is Earth - the sky is blue but seen from space the atmosphere is pretty much colourless. I don't know about Venus, I'm afraid. --Tango (talk) 23:27, 26 September 2008 (UTC)
- Above the clouds is probably above the main atmospher of Venus. If so, then it's probably black. It's uppermost layers is probably acid clouds. Our sky is light blue over Trophospher', the next layer of atmos' is probably dark blue, the toppest layer of our sky might be indigo.--57Freeways 00:03, 27 September 2008 (UTC)