Wikipedia:Reference desk/Archives/Science/2013 December 21
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December 21 edit
What does the letter C in anatomy stand for? edit
for example: the atlas (C1) is the first vertebra and is called C1.213.57.15.172 (talk) 13:22, 21 December 2013 (UTC)
- Cervical, in reference to the Cervical vertebrae, from the latin word cervix, which means neck. Nimur (talk) 13:34, 21 December 2013 (UTC)
- Thank you a lot! 213.57.15.172 (talk) 15:10, 21 December 2013 (UTC)
- As you work your way down, you'll also encounter the thoracic (T1-T12), lumbar (L1-L5), and sacral (S1-S5) vertebrae. - Nunh-huh 18:19, 21 December 2013 (UTC)
- As discussed in Vertebral column. In case the OP is wondering, the other use of "cervix" is in reference to the "neck" of the uterus. ←Baseball Bugs What's up, Doc? carrots→ 20:14, 21 December 2013 (UTC)
- As you work your way down, you'll also encounter the thoracic (T1-T12), lumbar (L1-L5), and sacral (S1-S5) vertebrae. - Nunh-huh 18:19, 21 December 2013 (UTC)
Biochemistry edit
Why Non-steroidal anti-inflammatory drugs could inhibit the healing of Stress fructures \ Arthritis, but won't be able to inhibit the healing of, Sore-throat inflammation or other inflammations in general?
and another question: Why won't these NSaid drugs can't reduce or heal the Inflammation of sore-throats or other inflammations in general? Thanks. Ben-Natan (talk) 17:30, 21 December 2013 (UTC)
- Don't think you should be asking these questions here. Try looking at (say) [1] or if you are affiliated with any legitimate institution that has an Athens account then log in here: [2].On Wikipedia ref desk we don't give detailed medical explanations such as this. For other editors: there is also the possibility that it will lead into a discussion about COX-1 and COX-2. Too complicated for our remit.--Aspro (talk) 01:02, 22 December 2013 (UTC)
- You heard it- no questions related to medicine in any way, ever. Also make sure not to ask any complicated questions because we might get confused! fart 68.0.144.214 (talk) 01:50, 22 December 2013 (UTC)
- You've asked a good question, and deserve good answers. It's a little hard to address because there's some dramatic tension between an industry that has tended to claim that whether you're a horse or a human your natural healing mechanism is off kilter and taking NSAIDs is going to be better than not doing so, and reports that actually NSAIDs slow the rate of repair. See [3] for a current review - this was obtained from PubMed, the all around best resource for sniffing out recent research. It cites a source saying both bone and tendon repair is slower. Fishing around I wasn't doing very well figuring out about sore throat duration - most studies focus on pain relief - but [4] said loxoprofen caused a "slight" delay in resolution of symptoms, and cites a source saying this is a general property of NSAIDs. Bear in mind that it is very difficult for experimenters to define how fast let alone how "good" healing is in a context separate from the immediate question of how much it hurts. Wnt (talk) 15:37, 22 December 2013 (UTC)
- @ 68.0.144.214 . Read between the lines. Look and contemplate the OP's questions! Here, on ref desk we do our best to answer readers general questions. From the grammar and syntax, I would bet my bottom dollar that this was posted buy a healthcare professional. 68.0.144.214,... the next time you go to your doctor, would you feel reassured by him saying : “Its OK 68.0.144.214. I have looked up your complaint up on Wikipedia Help Desk and they have told me the very remedy for your very complaint.” I would run a mile. For some one to ask these type of questions (as the OP did) they need to refer to reliable sources. So, cut the sarcasm out of this. OK!--Aspro (talk) 00:03, 23 December 2013 (UTC)--Aspro (talk) 00:03, 23 December 2013 (UTC)
Gaia Space Observatory Dimensions edit
I'm trying to find approximate dimensions of the Gaia spacecraft. From the European Space Agency fact sheet the sunshade is 10m in diameter but there is little info on the rest of the spacecraft. Wikipedias Gaia entry just says "4.6 m × 2.3 m" The approximate overall diameter of the thermal tent enclosing modules of the spacecraft is 3.8m according to http://www.russianspaceweb.com/gaia.html while the ESA website says the torus is approx 3m in diameter. Wikipedias 2.3 seems too small. The overall height or length of the whole spacecraft including both modules is 4.4 according to http://www.russianspaceweb.com/gaia.html ,3m according to Astrium, 3.5 according to spaceflight101 and perhaps 4.6 according to Wikipedia. I only need approx dimensions to the same roundings as mentioned above. Mhicaoidh (talk) 20:55, 21 December 2013 (UTC)
- You already have approximate dimensions for the entire spacecraft. If you want more precision, you need to be more specific about which dimension you want. So first, we need to describe Gaia in a little more detail - it's not a spherical cow; its geometry is quite complex. Now, finding out information about spacecraft isn't exactly rocket science, but it's something that the popular press and popular web search engines are both very bad at, even though there are plenty of great resources available.
- The Gaia (spacecraft) is comprised of a satellite platform and a payload module, plus a sunscreen "tent." Its chief contractor, Astrium (part of EADS) makes a very nice poster available to help orient the unfamiliar. The ESA's Gaia factsheet has some more dimensions; but if you really want to know the implementation details, the best place to look is Astrium's webpage and media materials (because they're the ones who actualy build the spaceship). Let's start with their press release - a very high-level review for journalists on launch-day.
- From there, I find an article on Gaia's telescope, giving some great optical parameters and dimensions for the telescope and its unusual reflector arrangement. There are two of those, oriented ninety degrees apart, for redundancy - because, as you will note from the ESA Gaia FAQ, the spacecraft is uninsured - official ESA policy is that the engineering times and costs to build complete dual-module-redundancy is still cheaper than spacecraft-insurance!
- From the telescope video, and the billion-pixel camera video, we get dimensions for the focal plane and the dimensions and arrangement of over 100 individual CCD image sensors. These work in parallel to locate stars and measure their spectra.
- In the 2012 article Sunblock for Astrometry, you can read the dimensions, geometry, and material properties of the four dozen triangles that comprise the sun shade.
- One of the novel features of Gaia is its structural torus, built from silicon carbide, that helps ensure perfect alignment and minimizes vibrations. As you've no doubt already discovered, silicon carbide is a specialty of Astrium, and one of the line-item reasons they got to build this satellite; this composite material has been used in the designs of previous and upcoming satellite observatories. It's sort of a weird very-strong, very-light ceramic-like, metal-like material (and it's hard to weld, cut, machine, glue, and so on). Digging into the archives, I find a 2009 article published to announce the completion of its construction. That article expounds on the geometry and dimensions of the "quasi-octagonal" torus.
- And if you've been following along in the links, you've also got emails and phone numbers for press- and media-relations contacts for all of the various subsystems, just in case you had a specific question about a specific dimension of some subsystem. But before you phone up any space agencies, make sure you're able to ask them some pretty darned well-informed questions.
- Nimur (talk) 18:30, 22 December 2013 (UTC)
- What a rude, arrogant and unhelpful response. You have misconstrued my question and thought I was asking for specifications of the space craft and equipment when I was asking for approximate overall physical dimensions. And yes, the Gaia spacecraft is broadly speaking a “spherical cow” resembling in the broadest terms a cylinder (capped with a shallow cone) sitting on a disc-like sunshade. The dimensions I mentioned in my post vary widely and I was seeking accuracy to one decimal point. I have previously visited all the websites you mention prior to my post and surprisingly they lack much information on the spacecraft dimensions. Yes I know Astrium built Gaia and the poster you mention gives only the diameter of the sunshade and spacecraft height, no module diameter. Likewise I have seen the ESA fact sheet and as I mentioned in my post it too has no information on the spacecraft dimensions: sunshade diameter only. Yes it had occurred to me to email the ESA helpdesk and other sources and although it has taken them a couple of days to reply, two sources have since emailed me a scaled plan and elevation. For copyright reasons they have requested I not post the images online but I have found that the diameter of the sunshade is 10.25m, the diameter of the spacecraft modules is 3.23m (to the outside of the thermal tent) and the overall height/length of the spacecraft is 3.32m (3.7m including antenna). Now instead of pursuing an argument with you and responding to your admonitions I shall do something useful such as correct Wikipedia’s Gaia Spacecraft entry. I suggest you find something useful and helpful to do as well.Mhicaoidh (talk) 22:03, 22 December 2013 (UTC)
- It seems some people can fit a 3m torus inside a 2.3m cylinder ;-). Did you get the diameter before unfolding as well? I was going to guess 3.80m based on this picture, since we know the outer diameter of the fairing is 4.1 m. Maybe the mass given in the article should be changed as well, I noticed that most sources give the total launch mass, but that includes the launch adapter which is left behind when Gaia separates from Fregat. The ESA mass budget gives a launch mass of 1934 kg, launch adapter 95 kg, total launch mass of 2029 kg. Anyway, nice job! Ssscienccce (talk) 00:11, 23 December 2013 (UTC)
- The torus - in fact, the entire spacecraft - is not circular. What parameter is the diameter measuring on this non-circular object? Perhaps you mean the diameter of a circle that circumscribes the structure? Or perhaps the diameter of the sphere that circumscribes it? Or perhaps the equivalent diameter for the maximal radius of curvature? By all means, if you find any reliable source that specifies, please update our article. But I suspect you cannot find better answers to the question, "what is the diameter," because it is an ill-defined question. To me, it makes perfect sense that you are finding conflicting answers - the parameter you're looking for is ill-defined. I apologize if you found my response unhelpful; my goal was to help refine your search into a more specific query so that you can get a better answer. Nimur (talk) 00:26, 23 December 2013 (UTC)
- Ssscienccce, thanks for your wit and intelligent surmise. The mass question is very pertinent but won’t trouble my 1 144 scale model too much ;-) Nimur, I know the torus is not circular but feel free to complain to the European Space Agency about their phrase “3-metre diameter, quasi-octagonal torus” at http://sci.esa.int/gaia/45330-the-gaia-torus-is-complete/ Before that, I suggest you look up the definition of diameter, it’s not what you think. In the same way, both the ESA and Astrium have referred to the dodecahedral sunshade as having a diameter of 10m in the info you cited. Given the rounding of that number, it’s accurate by dictionary definition, good enough for them and good enough for me. The same applies to the diameter of the Gaia spacecraft in its thermal tent, which has been supplied to me in drawn form by the Gaia helpdesk and by a sub-contractor to Astrium. Please, Nimur, stop trolling around this question unless you have something constructive to say. I posed the same original question here as I did to two other sites; they had no problem understanding it and responded usefully. In contrast you have given us a list of sites you have googled and then quibbled about the phrasing of my question. Have you referred me to any sites I haven’t seen before? No. Have you answered the question? No. Have you rebuked me? Yes. Is this the intent of the reference desk? No. Please stay away from my question. If I update the Gaia spacecraft article in a way that you feel breaches Wikipedia policy please feel free to complain over there.Mhicaoidh (talk) 06:31, 23 December 2013 (UTC)
- I find that you are the only person being rude here. I don't see a rebuke in either of Nimur's posts. Even if you believe he misunderstood your question, that does not justify your accusations of rudeness, arrogance, or trolling. It certainly doesn't justify your apparent expectation that he knows which sites you've seen before. If the other two sites you posted the question on gave you good answers, great. Now either obey WP:CIVIL, or get lost. --Bowlhover (talk) 07:43, 23 December 2013 (UTC)
- Im guessing you don't feel the phrase "get lost" is rude either. As the original poster I feel I was entitled to respond to someone who spent a lot of time on critique of my question rather than answering it. If you read my question more closely you will see all the websites Nimur suggested were all mentioned in my original post. I came here as a last resort and it has unfortunately been a waste of time and energy. As you will see from my edit history I was once a constructive contributor to the reference desk. I went away once and Im sorry I came back asking a good faith question, not expecting to be bitten. Mhicaoidh (talk) 08:24, 23 December 2013 (UTC)
- Well if you don't like someone's answer, why don't you just ignore it, rather than calling them "rude, arrogant"? You can explain why you find the answer unhelpful if it will help others to provide more helpful answers, but there is no need to use insulting words. --Lgriot (talk) 11:58, 23 December 2013 (UTC)
- BTW, Nimur the sentence "Make sure you're able to ask them some pretty darned well-informed questions" is not helpful. We are here to help people who are looking for information, so it should be no surprise to you that they are not as "well informed" as you think you are. --Lgriot (talk) 12:03, 23 December 2013 (UTC)
- Im guessing you don't feel the phrase "get lost" is rude either. As the original poster I feel I was entitled to respond to someone who spent a lot of time on critique of my question rather than answering it. If you read my question more closely you will see all the websites Nimur suggested were all mentioned in my original post. I came here as a last resort and it has unfortunately been a waste of time and energy. As you will see from my edit history I was once a constructive contributor to the reference desk. I went away once and Im sorry I came back asking a good faith question, not expecting to be bitten. Mhicaoidh (talk) 08:24, 23 December 2013 (UTC)
- I find that you are the only person being rude here. I don't see a rebuke in either of Nimur's posts. Even if you believe he misunderstood your question, that does not justify your accusations of rudeness, arrogance, or trolling. It certainly doesn't justify your apparent expectation that he knows which sites you've seen before. If the other two sites you posted the question on gave you good answers, great. Now either obey WP:CIVIL, or get lost. --Bowlhover (talk) 07:43, 23 December 2013 (UTC)
- So you posted five links where the OP could find more "dimensions", namely three pages that talk about the "diameter" of a non-circular object (one of them also gives the "length" of a triangle) and two that specify the dimensions of a non-circular object simply as being "10 metres across", but you only realized that these terms were meaningless/ill-defined after I used them in my post? There's a list of cognitive biases that may provide some insight. Ssscienccce (talk) 14:04, 23 December 2013 (UTC)
- Ssscienccce, thanks for your wit and intelligent surmise. The mass question is very pertinent but won’t trouble my 1 144 scale model too much ;-) Nimur, I know the torus is not circular but feel free to complain to the European Space Agency about their phrase “3-metre diameter, quasi-octagonal torus” at http://sci.esa.int/gaia/45330-the-gaia-torus-is-complete/ Before that, I suggest you look up the definition of diameter, it’s not what you think. In the same way, both the ESA and Astrium have referred to the dodecahedral sunshade as having a diameter of 10m in the info you cited. Given the rounding of that number, it’s accurate by dictionary definition, good enough for them and good enough for me. The same applies to the diameter of the Gaia spacecraft in its thermal tent, which has been supplied to me in drawn form by the Gaia helpdesk and by a sub-contractor to Astrium. Please, Nimur, stop trolling around this question unless you have something constructive to say. I posed the same original question here as I did to two other sites; they had no problem understanding it and responded usefully. In contrast you have given us a list of sites you have googled and then quibbled about the phrasing of my question. Have you referred me to any sites I haven’t seen before? No. Have you answered the question? No. Have you rebuked me? Yes. Is this the intent of the reference desk? No. Please stay away from my question. If I update the Gaia spacecraft article in a way that you feel breaches Wikipedia policy please feel free to complain over there.Mhicaoidh (talk) 06:31, 23 December 2013 (UTC)
- The torus - in fact, the entire spacecraft - is not circular. What parameter is the diameter measuring on this non-circular object? Perhaps you mean the diameter of a circle that circumscribes the structure? Or perhaps the diameter of the sphere that circumscribes it? Or perhaps the equivalent diameter for the maximal radius of curvature? By all means, if you find any reliable source that specifies, please update our article. But I suspect you cannot find better answers to the question, "what is the diameter," because it is an ill-defined question. To me, it makes perfect sense that you are finding conflicting answers - the parameter you're looking for is ill-defined. I apologize if you found my response unhelpful; my goal was to help refine your search into a more specific query so that you can get a better answer. Nimur (talk) 00:26, 23 December 2013 (UTC)
- It seems some people can fit a 3m torus inside a 2.3m cylinder ;-). Did you get the diameter before unfolding as well? I was going to guess 3.80m based on this picture, since we know the outer diameter of the fairing is 4.1 m. Maybe the mass given in the article should be changed as well, I noticed that most sources give the total launch mass, but that includes the launch adapter which is left behind when Gaia separates from Fregat. The ESA mass budget gives a launch mass of 1934 kg, launch adapter 95 kg, total launch mass of 2029 kg. Anyway, nice job! Ssscienccce (talk) 00:11, 23 December 2013 (UTC)
- What a rude, arrogant and unhelpful response. You have misconstrued my question and thought I was asking for specifications of the space craft and equipment when I was asking for approximate overall physical dimensions. And yes, the Gaia spacecraft is broadly speaking a “spherical cow” resembling in the broadest terms a cylinder (capped with a shallow cone) sitting on a disc-like sunshade. The dimensions I mentioned in my post vary widely and I was seeking accuracy to one decimal point. I have previously visited all the websites you mention prior to my post and surprisingly they lack much information on the spacecraft dimensions. Yes I know Astrium built Gaia and the poster you mention gives only the diameter of the sunshade and spacecraft height, no module diameter. Likewise I have seen the ESA fact sheet and as I mentioned in my post it too has no information on the spacecraft dimensions: sunshade diameter only. Yes it had occurred to me to email the ESA helpdesk and other sources and although it has taken them a couple of days to reply, two sources have since emailed me a scaled plan and elevation. For copyright reasons they have requested I not post the images online but I have found that the diameter of the sunshade is 10.25m, the diameter of the spacecraft modules is 3.23m (to the outside of the thermal tent) and the overall height/length of the spacecraft is 3.32m (3.7m including antenna). Now instead of pursuing an argument with you and responding to your admonitions I shall do something useful such as correct Wikipedia’s Gaia Spacecraft entry. I suggest you find something useful and helpful to do as well.Mhicaoidh (talk) 22:03, 22 December 2013 (UTC)
