Wikipedia:Reference desk/Archives/Science/2006 December 2
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December 2
[edit]Eyes
[edit]What causes the "gluggy" feeling in your eyes when you are tired, and when you first wake up? BenC7 04:43, 2 December 2006 (UTC)
- It's most likely sleep inertia, which usually happens, as you describe it "when you first wake up."--Mango Sango 06:56, 2 December 2006 (UTC)
Dust that's been slowly accumulating over the last eight hours. Lovely, no? -- Theavatar3 01:09, 3 December 2006 (UTC)
Oedema?--Light current 01:14, 3 December 2006 (UTC)
- Hmm, I don't think it's any of those. Sleep inertia is more to do with dexterity than with a "scaley" type of feeling on the eyes. It also happens when you are getting tired but haven't been asleep. It can't be dust, because it's there when you wake up, after your eyes have been closed. I also doubt it would be oedema, because well - I just don't think it is that. But I could be wrong. BenC7 02:38, 4 December 2006 (UTC)
Absurd particle accelerators
[edit]Where is a good place to find detailed information on early attempts to create a particle accelerator using the voltage potential of lightning? --Deglr6328 11:55, 2 December 2006 (UTC)
- If you Google "Brasch Lange lightning" you'll get a bunch of results on the most famous of these early attempts (which resulted in Lange's death). (And they're not that absurd. At the time lightning provided far higher energies than you could get with cyclotrons or linear accelerators. It was hard to justify the incredible costs for large accelerators in the years before the bomb, as well.) --24.147.86.187 17:35, 2 December 2006 (UTC)
- There's very very little in depth information out there that I can find....--Deglr6328 11:14, 3 December 2006 (UTC)
Earliest memories
[edit]I can clearly remember this event, quoted from the page for The Price is Right,
- "The most frequently mentioned blooper happened in 1977 when at the beginning of the show, a woman named Yolanda Bowsley was called to come on down. Bowsley ran so hard to Contestants' Row and failed to notice her tube top slipped off, exposing her breasts."
It's no wonder that the memory stuck with me but what I'm curious about is whether I was seeing the original broadcast or a rerun. I turned 3 years old in Nov. 1977, so would I be able to have retained this memory from the original? Dismas|(talk) 14:01, 2 December 2006 (UTC)
- Perhaps. But as it's "The most frequently mentioned blooper" can you be sure you've not seen it since in a blooper show? -- Finlay McWalter | Talk 14:25, 2 December 2006 (UTC)
- I don't think it was a blooper show. I seem to recall that it was morning/noon time. A blooper show would have been in the early evening at least. And I didn't have cable when I was a kid (if that was even available in the late 70s/early 80s) and I don't think network television would have gotten it on a blooper show then re-broadcast that blooper show during the day. Dismas|(talk) 15:32, 2 December 2006 (UTC)
- Weird, I was going to ask almost this same question the other day. I can very clearly remember a certain toy I had received at Christmas, when I was just over one year old. It was a caterpillar-shaped pull toy with wheels, it was green, and the wheels had milled edges (like on a US quarter or dime). The milling fascinated me, I loved the texture of it. I also liked the smooth texture of the hearth in front of the fireplace in that house. We moved out a little less than a year later. Many years after that, my father showed me a picture of me, as a baby, crawling on the hearth and playing with the toy caterpillar. 192.168.1.1 2:10pm, 2 December 2006 (PST)
- If it was plastic and had a yellow seat, I think I had the exact same toy. Dismas|(talk) 23:15, 2 December 2006 (UTC)
- Weird, I was going to ask almost this same question the other day. I can very clearly remember a certain toy I had received at Christmas, when I was just over one year old. It was a caterpillar-shaped pull toy with wheels, it was green, and the wheels had milled edges (like on a US quarter or dime). The milling fascinated me, I loved the texture of it. I also liked the smooth texture of the hearth in front of the fireplace in that house. We moved out a little less than a year later. Many years after that, my father showed me a picture of me, as a baby, crawling on the hearth and playing with the toy caterpillar. 192.168.1.1 2:10pm, 2 December 2006 (PST)
- I can remember a tiny bit from when I was 3-4, so I'd say it's possible. I don't remember anything at all earlier than that though. --Wirbelwindヴィルヴェルヴィント (talk) 19:45, 3 December 2006 (UTC)
- My earliest memory is lying in my cot at night. I pushed my eiderdown off to experience cold (at that age I dont think I understood the connotations of 'cold' or 'warm'). I must have fallen asleep, because when I awoke later that night I felt warm: someone has put the eiderdown back over me. I've never ever told that to anyone before. 62.253.44.1 21:03, 8 December 2006 (UTC)
type clotting component
[edit]Recently I cut a long deep gash in my hand with a utility knife. The location and direction of the cut was such that I could apply compression immediately sufficient to stop the bleeding by simply touching the tip of my thumb with the tip of my little finger and then using cord to bind my hand in this position. After about 45 minutes when the blood had dried I began cleaning my hand with alcohol. I noticed that the dried blood was extremely difficult, almost as difficult as superglue, to remove. Out of curiosity I removed the cord and opened my hand to see if the wound would bleed and to my amazement it did not even ooze. What could be in my diet that would cause my blood to bind and seal the wound after less than an hour of compression? 71.100.6.152 16:36, 2 December 2006 (UTC)
- To answer your question specifically: vitamin K and calcium are two nutrients that are needed for coagulation. Coagulation and vascular repair, however, are complicated cascades which are more profoundly affected by endogenous signals than exogenous ones (at least, in the hyperthrombic direction, there are certainly many easily obtainable anticoagulants that will "thin" your blood, but not many things that will acutely "thicken" it). It is impossible to assess whether or not your particular event was abnormal or not without a much better survey of exactly what damage was done and how long it took to set. However, there are a number of conditions (some common, approaching 3%) which result in a hypercoagulable state. I would very strongly reccommend that if you think your blood forms clots more rapidly than typical you visit a physician for a more thorough investigation. I realize that it is nice that your cuts stop bleeding rapidly, but hypercoagulation is a serious condition that deserves attention, if not for treatment, than for education on the warning signs of deep vein thrombosis pulmonary embolism embolic stroke &c. Some people might recommend 81mg per day aspirin to individuals in a hypercoagulable state, but I wouldn't in this case: I would never give medical advice over the internet. Oh, and in the future, you really should clean the cut before the clot forms --This is not medical advice. See a doctor if you think you have a non-hypothetical medical problem-- Tuckerekcut 18:21, 2 December 2006 (UTC)
- Normally when I clean a wound first the blood is unable to seal the edges thereafter. In this case the cut itself (except in a couple of places where the edges are slightly misaligned) is still covered with coagulted blood that could not be removed after a fair amount of cleaning with significant pressure. What could cause the blood to coagulate in such a super cohesive state? The knive was razor sharp and the cut now appears under a magifier to be no wider than a fingerprint valley. The length of the cut is about 1.5 inches and looks to be at least 5/16 inches deep near the mid point. The skin around the cut is beginning to show the signs of mild bruising (purple). 71.100.6.152
- I'm afraid I don't know what could have been on your hand to have caused that. That the knife was razor sharp suggests that the wound was clean (from a morphological, not microbiological perspective) enough to repair rapidly. Again, though, I feel that I should supply a warning. The contents of the hand and arm are differentiated into discrete compartments. Sometimes, when there is bleeding or other fluid input into one compartment, it can swell significantly in a small area and compress vital structures like nerves and arteries (and veins, making the problem worse). If your hand swells uncomfortably around the cut, consider a compartment syndrome and see a physician immediately. Similarly if there is circumferential or streaky redness, swelling, or discharge, consider infection and see a physician immediately. Sorry I am being so wordy without answering your question, but hands and arms are pretty important... --This is not medical advice. See a doctor if you think you have a non-hypothetical medical problem-- Tuckerekcut 00:09, 3 December 2006 (UTC)
- I noticed that too sometimes with cuts by a very sharp knife. But it doesn't always occur. The explanation I had come up with is, I suppose, what Tuck meant with a 'clean' cut, that the edges are put back together to align perfectly, so no new tissue needs to be formed in the sense of reconnecting the vessels and such - they are already in perfect alignment. DirkvdM 07:35, 3 December 2006 (UTC)
Gear Pumps
[edit]My Dad's having trouble with a hydraulic gear pump that operates a four post lift in a garage. The pump is driven by an electric motor. The old pump broke (it was too old to get an exact replacement). When he fitted a new pump the oil seal on the drive shaft burst with the hydraulic pressure and filled the electric motor with oil. What could cause this to happen? Cheers, Jilly 18:51, 2 December 2006 (UTC)
- Sounds as though the new pump is not up to the job in terms of pressure rating. Check the specification on the old pump which will probably have something somewhere about its maximum psi. The new pump needs to be able to withstand this pressure.--Shantavira 19:53, 2 December 2006 (UTC)
- Do you know if anything else could have caused this? Just the new pump was supplied by what I believe is a reputable firm who knew what the pump was going to be used for. I even provided them with the old pump so they could check that the replacement was suitable. Jilly 20:09, 2 December 2006 (UTC)
- Safety note: When hydraulic fluid sprays out at high pressure, there is a danger that it will cause death or injury by penetrating the skin. It can spray right through skin and tissues. It can form a deposit in the tissues, necessitating surgery to avoid loss of a limb. Workmen are supposed to wear protective gear. Edison 20:22, 2 December 2006 (UTC)
I have a theory:
The old pump was operating at reduced pressure, due to normal wear. This allowed the old, worn seal, which could not have withstood full pressure, to continue to hold. The replacement pump, while rated for the same pressure output, in reality produced significantly more pressure than the old pump. Thus, the old seal was unable to withstand this higher pressure. StuRat 08:02, 3 December 2006 (UTC)
- If the pressure relief valve was faulty and the pump outlet was blocked would the pump stop the electric motor or would this cause the seal to blow? Jilly 14:10, 3 December 2006 (UTC)
- If there is an automatic shutoff mechanism, then it would shut down eventually, but not until after the pressure increased to a pt that might breach the seal. Note, however, that pressure relief valves are normally designed to fail in the "stuck open" position, not "stuck closed". StuRat 14:21, 3 December 2006 (UTC)
I think it unlikely, but you should also consider the possibility of a "sample defect", that is, this one sample of the new pump design was defective from the start and there's nothing wrong with the specification/application. As I say, it sounds unlikely in this case, but it is possible.
Atlant 13:50, 4 December 2006 (UTC)
Access To Scientific Journals
[edit]If I went to work in some lowly position at a pharmaceutical production facility, not involved in research myself, could I expect access to journal articles that would be provided for the researchers in the company? The company is a subsidiary of Johnson & Johnson. --Username132 (talk) 19:42, 2 December 2006 (UTC)
- I would think that you should ask your company this question. You may be able to access online articles via computers at your work. --Russoc4 20:01, 2 December 2006 (UTC)
- Many organisiations that subscribe to academic journals have company wide access. Thus if you had access to a computer a company IP address, you may be able to access them online. Also - though it is less common that it used to be - big pharma may have their own library on site with hard copies of journals that you could browse. In the two companies I have worked for, there was nothing stopping any employee accessing academic journals. Rockpocket 22:54, 2 December 2006 (UTC)
GM Roundup Ready canola gene traits
[edit]I've been trying to find the genes that have been inserted into roundup ready canola in order to confer their resistance to glyphosate. In Wikipedia, you've made reference to naturally occuring plant genes but haven't listed them. It would be really awesome if you could let me know which specific plant/fungal/microbial genes were inserted or if you know of a link to which I can find that information myself. The roundup link on the page redirected me to scotts towels? Weird. Anyways, thanks in advance.
Colin
- This might get you started: Glyphosate#Glyphosate resistance. --JWSchmidt 22:13, 2 December 2006 (UTC)
Sight and taste
[edit]How does sight affect your taste?
- Taste (gustation) or Taste (aesthetics)? If the former, do you mean what things taste like to you, or how you taste to other things? GeeJo (t)⁄(c) • 22:58, 2 December 2006 (UTC)
- I suppose you don't mean synesthesia. But I have seen tests where people would find an artificially green-coloured steak tasted bad, but a blindfolded control group ate it with gusto. Is that what you mean? DirkvdM 07:39, 3 December 2006 (UTC)
- When they taste wine blindfolded, 80% of the blahblah about it proves wrong, e.g. people are confusing red and white wine and still speak of it as if they saw its colour. -- DLL .. T 17:35, 3 December 2006 (UTC)
component/vga compatabilty
[edit]I've become aware of cables designed for a (HD15)VGA input that are terminated with 3 RCA plugs/sockets. So this must mean that the sync signal is in one of the 'rgb' signals, and there is no separate h-sync or v-sync. eg Sony SDM-E76D [[1] see 'supplied accessories']
My question is this - what uses or how common is a '3 wire' signal for connection to VGA, and could this be compatable with component signals ala DVD outputs etc.
I'll just be grateful if someone can explain the purpose of such a connector - as they are new to me.83.100.250.215 22:32, 2 December 2006 (UTC)
- You may find you get a faster answer if you post this over on the Computing reference desk. GeeJo (t)⁄(c) • 23:02, 2 December 2006 (UTC)
- Good point!
- Maybe called sync on green. sEe [2]
- Can anyone explain just how compatable vga and component would be if the vga device accepts sync on green?
The human spleen pore size
[edit]So I am doing a research project about the human spleen. Like any other organ it has cells (stromal, macrophages, B and T cells) and an extra cellular matrix. My research deals with decellularization. I found a couple of articles about new techniques fo decellularization and new detergents that work rather well. Basically once you perform decellularization, you're left with an ECM scaffold which is simmilar to a porous filter. I need to find an estimate of the average size of a pore in that scaffold. I've looked at numerous articles but I can't find that figure anywhere.
On the same note I was trying to find the average size of a macrophage or a B cell, and couldn't find it anywhere.
Thanks a lot
teo
- With regards to the second question, try doing a search in this online book. As for the first question, I doubt anyone here will know; it is a very specialized piece of data. BenC7 02:44, 4 December 2006 (UTC)