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Wikipedia:Reference desk/Archives/Science/2014 January 29

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January 29

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Danny DeVito health problem

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Hello Learned Ones ! I am following my program "Do now what you never had time to do in the past years" & just watched Friends (season 10) 11th episode "The One Where the Stripper Cries" (Feb. 2004) . I was flabbergasted at Danny DeVito 's performance as a distorted and aged stripper. I also brooded (as a M.D., & from a medical point of view) about his legs problem : hidden by the pantaloon he kept on, they seemed to me very thin, paralysed, & not flexing, maybe held up by stilts, while his torso seems about normal. WP does not give any hint about his ailment. Can somebody tell me what it is ? Poliomyelitis sequel ? Neural horse-tail malformation ? General osteo-formation disease ? Anyway, hats down in front of the man's stamina & mind power ! Thanks beforehand for your answers. T;y. Arapaima (talk) 09:02, 29 January 2014 (UTC)[reply]

Multiple_epiphyseal_dysplasia (See: Multiple_epiphyseal_dysplasia#Prominent_people_with_this_condition No inline citation.) 196.214.78.114 (talk) 10:24, 29 January 2014 (UTC)[reply]
I'm struggling to find a reliable reference. This one is a "scholarly" one. See page 5: http://eresearchau.files.wordpress.com/2013/02/eresearch-2013-presentation_craig-mcnamara.pdf 196.214.78.114 (talk) 10:52, 29 January 2014 (UTC)[reply]
Yes! my 3d hypo. was about right ! Thanks a lot 196.214.78.114 ! Arapaima (talk) 11:03, 30 January 2014 (UTC)[reply]

Preferred format for Gene Wiki articles

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Hi,

I am an instructor of a bioinformatics course at the University of Minnesota. We write Wikipedia articles each year on human genes of unknown function for which there are usually only stubs at the outset. I forwarded a message from someone going by "Boghog" (Boghog (talk) 17:35, 13 May 2013 (UTC) asking me to contact him so that I could ensure my students' pages are more compliant with the format of other Gene Wiki articles. I'm not sure how to contact him but perhaps you could help me do this. He gave no email address. Thanks!

David Matthes University of Minnesota — Preceding unsigned comment added by 134.84.13.8 (talk) 20:04, 29 January 2014 (UTC)[reply]

You can post a message for him at User talk:Boghog (click on the "New section" tab and enter an appropriate header for your message). This sort of question is really more appropriate for the Help Desk (but there's nothing wrong with asking it here). Tevildo (talk) 20:43, 29 January 2014 (UTC)[reply]

Bed rest

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What's the minimum required dose of non-bedrest to prevent permanent damage? (On Earth). The nasa bed rest study apparently causes permanent damage. 12.196.0.56 (talk) 22:20, 29 January 2014 (UTC)[reply]

Damage from what? Can you please explain your question more clearly? Are you asking about bed rest (header) or non-bed rest (question)? -- Jack of Oz [pleasantries] 22:51, 29 January 2014 (UTC)[reply]
Pending clarification, one big problem with being bedridden is getting nasty skin problems, which can lead to further infection, etc. If you're interested in that, see bed_sore#Prevention, and the references therein. Also, the US government has a comparison of preventative guidelines here [1]. SemanticMantis (talk) 23:28, 29 January 2014 (UTC)[reply]
I imagine you don't get bedsores without gravity, though. —Tamfang (talk) 18:28, 31 January 2014 (UTC)[reply]
Going by this:[2] it suggest a max of about 9 hours Per diem.I.e., not bed-rest but sleep--Aspro (talk) 23:37, 29 January 2014 (UTC)[reply]
Damage from anything, but they get bone and maybe muscle loss don't they? Though maybe muscle cells don't die (I don't know) so you could regain lost muscle mass? 12.196.0.56 (talk) 23:28, 30 January 2014 (UTC)[reply]
Don't take this as gospel because over the decades my memory has faded. Yet, this is the gist: Brain and nerve cells survive the longest [3]. The rest of the body cells are constantly undergoing renewal. If one is (say) a weight lifter, the stresses of that exercise is causing little tears in the muscles and bones. The body repairs these and makes the muscles larger and the bones thicker and more dense. This is how a osteoarchaeology can tell if skeletal remains were from a peasant used to hard labour or a noble man or lazy abbot. Spend six months in the International Space Station with its lesser physical demands on the human frame and muscle and bone mass is lost. Cells die by a process called Apoptosis. If you don't use them – you lose them.--Aspro (talk) 00:36, 2 February 2014 (UTC)[reply]
What's the impact of strenuous physical exercise on bone mass, compared with its impact on muscle mass? You see plenty of body-builders with large visible muscle mass (especially if they reduce fat mass as well so that it's more visible), but I've never heard discussions about significant increases in bone mass or volume as a result of such activity. --Demiurge1000 (talk) 00:52, 2 February 2014 (UTC)[reply]
Good question: You may have not never heard discussions about significant increases in bone mass or volume as a result of such activity but I think it is an accept fact these days....Exercise Increases Bone Mass: Start Early For Long-Lasting Effects and (so on) for the last forty years. If you don't use 'em – you lose 'em. An' if you use them a lot you get more.--Aspro (talk) 22:07, 2 February 2014 (UTC)[reply]

Sequence

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Is this the correct sequence; gamete, zygote, morula, blastocyst, embryo, fetus? If so, are there any which i have missed out on?

Details of embryogenesis can change, depending on the species. If you are interested in humans, see Human_embryogenesis and Prenatal_development (which is human-centric). Terminology may vary somewhat, but our article says it's an embryo from first cell division until birth. In that sense, zygotes, morulae, and blastocysts are all embryos. Fetus, however says that embryo-hood ends and 9 weeks in humans. SemanticMantis (talk) 23:38, 29 January 2014 (UTC)[reply]
Not to my reading. An embryo can be in the zygote or morula stage, but the way the OP writes it seems to imply that a blastocyst turns into an embryo (i.e. it was not an embryo before), which is contrary to our article's explanation. SemanticMantis (talk) 15:45, 30 January 2014 (UTC)[reply]
Yes, I see your point. Kind of like listing New Years Eve, January, February, Winter, Spring. μηδείς (talk) 18:05, 30 January 2014 (UTC)[reply]

Organic compounds

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Why is octanol thicker than octane? At least by boiling point, if not actually thickness. Long enough alcohols become solid even at body temperature. Is there like a gel phase or do they just suddenly freeze? What would it be like to swallow or gargle various pure alcohols? I'm not going to try it (okay, I put 70% isopropyl in my mouth once - My palate instantly shriveled like a prune). Even if it'd just be shriveling and pain at least tell me what the consistency would be like. — Preceding unsigned comment added by 12.196.0.56 (talk) 22:41, 29 January 2014 (UTC)[reply]

The reason for the higher freezing and boiling points is because octanol is a polar molecule which exhibits a fairly high degree of hydrogen bonding. As for what's it like to swallow the stuff -- I don't know, and I don't want to try. 67.169.83.209 (talk) 07:35, 30 January 2014 (UTC)[reply]
Alcohols generally have a lot in common regarding their toxicity and effects, with the bigger ones generally being worse. I remember Russians who had lived under Gorbachev told me that some people there had used to drink isopropanol, at about half the dosage of ethanol. I assume they diluted it - even ethanol is dangerous to drink at high purity levels. gamma-hydroxybutyrate (GHB) is another alcohol that had a fad of popularity in the 1990s. After an immense amount of hype on the part of sellers and demonization on the part of authorities, the net result was that they banned a formerly very useful industrial solvent (I remember reading the parent cyclic compound could dissolve a shoe, not sure what brand). You can look up the MSDS for octanol from various sources - they tend to be vague and have scanty information, but apparently it causes vomiting, respiratory depression ... stuff you'd expect from an alcohol. It's very difficult to look up the toxicity in better sources because many toxicity studies are done using it in a purely technical capacity. For all I know, with a good PR team and some ambition somebody might make the next big fad out of it, but aside from the money to be made this has nothing to be recommended. Wnt (talk) 17:21, 30 January 2014 (UTC)[reply]
Thanks for all the information, and I'd like to throw out a little food for thought.
The toxicity of any alcohol depends on at least two things - its activity on the central nervous system, a direct physiologic effect traced to the alcohol itself, and what various alcohol dehydrogenase enzymes break it down into. The alpha-hydroxy acids (glycolic, acetic, citric, lactic, etc.) also are acted on by alcohol dehydrogenase and other enzymes.
Methanol is metabolized by alcohol dehydrogenase into formaldehyde, which attacks the central nervous system irreversibly... causing blindness, coma and death.
By contrast, ethanol is metabolized by that same enzyme into acetylaldehyde, which is further metabolized into acetic acid by acetaldehyde dehydrogenase within 90 seconds of introduction into the human body, so a bout with ethanol is mainly remarkable for ethanol's direct effects with numerous brain enzyme receptors - the "high" of ethanol. Hangovers are caused by acetaldehyde and other aldehydes formed by the action of enzymes on ethanol and other substances in liquor.
Octanol is metabolized by 1-octanol dehydrogenase to octanal, an aldehyde made naturally in citrus oils. Octanol shares a common effect with other alkane alcohols on the nerve cell membrane which has been documented in Pharmacol Toxicol. 1990 Jul;67(1):56-60. The effects of alcohols in vitro on the nervous cell membrane measured by changes in the (Ca2+/Mg2+) ATPase activity and fluidity of the synaptosomal membrane. Edelfors S, Ravn-Jonsen A.
At this point, I reiterate what everyone else has said - we don't do health advice here. I just note that at least one published paper refers to the activity of all alcohols on the nerve cell membrane and has referred to other mechanisms as yet undescribed in their action on nerve cells.
I sure wouldn't drink it. loupgarous (talk) 05:04, 2 February 2014 (UTC)[reply]