carroll@s.cs.uiuc.edu (03/09/89)
I saw a report recently that had a Get-Away-Special mission that was
sending up half of a set of ``identical'' chicken eggs, the other half staying
on the ground as a control group. While not exactly human development, I'd
say it's certainly a first step in such research.
Alan M. Carroll "And then you say,
carroll@s.cs.uiuc.edu We have the Moon, so now the Stars..." - YES
CS Grad / U of Ill @ Urbana ...{ucbvax,pur-ee,convex}!s.cs.uiuc.edu!carrollpjs@ARISTOTLE-GW.JPL.NASA.GOV (Peter Scott) (03/11/89)
vsi1!v7fs1!mvp@apple.com (Mike Van Pelt) writes: > I'm not sure rats have enough brains to figure out how to >accomplish zero-G sex. Who needs brains when you have natural selection? :-) Peter Scott (pjs@grouch.jpl.nasa.gov)
robina@tekig5.PEN.TEK.COM (Robin Adams) (03/11/89)
In article <8Y42Wly00XokQ3qUUv@andrew.cmu.edu>, jd3l+@andrew.cmu.edu (Jean-Marc Debaud) writes: > I would like to have some informations on the following subject: > > What would be the reactions of an child conceived in space, > who spend its featal time in space, is born in space, live a few > years in space ? > > Could anyone tells me if any studies have been made on the > reaction of the immune system, psychology, agility under 0g > conditions and problems that he/she would have on hearth, > bornwith instinctive reactions... etc.. > The holistic evidence is beginning to point to the fact that 0G is not good for humans (-0G, not Space as a whole). Some mammalian studies (ref: COSMOS Mission Results / Ames / 89-18) have shown a decrease in immune functions (vitality?), a curbing of fast muscle response (agility), and a reduced testes weighting (virility). Most of this does not seem insummountable - Use of hormones, exercise, etc. The good news is that there seems some evidence of enlightment in humans. More than a few astronauts seem to have got quite spiritual (even religious) after spending time in space. However, I'm sure that has much more to do with their changed environmental perspective as a whole than 0G. o o o o o o o o ---------------------------------------------------------------------------- | | | | Robin /---------\ Adams
jokim@jarthur.Claremont.EDU (John H. Kim) (03/12/89)
This is my first posting so please excuse any botches :-) I vaguely recall (sorry, don't remember where) a study that found out that fetal development in bird eggs involved the cells at the bottom of the undifferentiated cell mass *always* differentiated into the head (or some other specific body part--I don't remember). The obvious conclusion would be that gravity provides a sort of compass for the same types of cells (neural, muscular, etc) to aggregate in the same place. I think the source went on to say something about babies conceived and developed without gravity possibly ending up as just a mass of cells. I think the next shuttle flight (or one forthcoming) involves an experiment about this. John H. Kim jokim@jarthur.Claremont.EDU uunet!muddcs!jarthur!jokim
chiaravi@silver.bacs.indiana.edu (Lucius Chiaraviglio) (03/13/89)
_ This is actually in response to several of the recent sci.space articles about embryonic development in zero gravity. In article <466@jarthur.Claremont.EDU> jokim@jarthur.UUCP (John H. Kim) writes: >I vaguely recall (sorry, don't remember where) a study that found out >that fetal development in bird eggs involved the cells at the bottom of >the undifferentiated cell mass *always* differentiated into the head (or >some other specific body part--I don't remember). The obvious >conclusion would be that gravity provides a sort of compass for the same >types of cells (neural, muscular, etc) to aggregate in the same place. >I think the source went on to say something about babies conceived and >developed without gravity possibly ending up as just a mass of cells. The problem with generalizing observations of birds, reptiles, and amphibians to all vertebrates is that these vertebrates (and at least most if not all fish) have very large yolky eggs whose cell division is distorted by the yolk, which is itself influenced by gravity (it is heavier, so non-yolky parts of the egg float over it. Thus it makes sense that embryonic development in these animals might evolve to take cues from gravity. Effects of gravity on Xenopus development have already been demonstrated, but of course the effect of zero gravity has not been tested. Thus, even this is not necessarily an example of Xenopus (or its ancestors) having evolved specifically to take a cue from gravity, but may just be an example of development proceeding abnormally as a result of gravity in the wrong direction. Reason for suspecting the latter comes from the same experiments showing the effects of gravity in the wrong direction, in which some of the eggs are immune to these effects -- the immunity has been shown to be directly correlated with rigidity of the cytoplasm of the eggs, which tends to prevent the cytoplasm from being sheared out of alignment with the cortex (which is what usually happens to eggs held at the wrong orientation). I got this information in personal communication with the principal investigators performing these experiments and discovering the effect of cytoplasmic rigidity: Tony Neff and George Malacinski at Indiana University. (This information is also published, but I can't remember which journal it was published in.) Even if the above-mentioned vertebrates do take actual developmental cues from gravity, it is unlikely that mammals do so. First of all, mammalian eggs are very small (microscopic) and do not have much yolk, so forces of 1 gravity are unlikely to effect them unless they have a specific gravity detection capability. Even more important, it would be very detrimental for mammalian embryos (other than those of monotremes such as platypuses) to depend on gravity in order to develop properly, because they are carried within their mother, which provides them with many advantages but also means that it is impossible to guarantee a constant direction of gravity in any but the largest mammals (and even these roll over occasionally) and impossible to guarantee even a predominant direction of gravity in highly active mammals such as tree-climbers and burrowing mammals. Therefore it seems highly likely that early mammalian embryonic development will be much affected by zero gravity unless the physiological state of the mother is altered too much. The upshot of all this is that if you want to eat pork or beef in space you need only have enough room to grow the animals (-: and some appropriate device to alleviate the obvious problems that will develop in a barn in zero-gravity :-), but if you want chicken or frog legs you are going to have to import these items or bring a centrifuge. 8-) -- | Lucius Chiaraviglio | ARPA: chiaravi@silver.bacs.indiana.edu BITNET: chiaravi@IUBACS.BITNET (IUBACS hoses From: fields; INCLUDE RET ADDR) ARPA-gatewayed BITNET: chiaravi%IUBACS.BITNET@vm.cc.purdue.edu Alt ARPA-gatewayed BITNET: chiaravi%IUBACS.BITNET@cunyvm.cuny.edu
khai@amara.uucp (S. Khai Mong) (03/13/89)
What about the position of the fetus in the womb? And the orientation of the baby during delivery? Surely gravity factors into these. -- Sao Khai Mong: Applied Dynamics, 3800 Stone School Road, Ann Arbor, Mi48108 (313)973-1300 (uunet|sharkey)!amara!khai khai%amara.uucp@mailgw.cc.umich.edu
eliz@nuchat.UUCP (Elizabeth Nuchia) (03/13/89)
In article <218100013@s.cs.uiuc.edu> carroll@s.cs.uiuc.edu writes: > I saw a report recently that had a Get-Away-Special mission that was >sending up half of a set of ``identical'' chicken eggs, the other half staying >on the ground as a control group. While not exactly human development, I'd >say it's certainly a first step in such research. I believe that this experiment is a student experiment and will be flying in the crew cabin middeck area. Get-Away-Specials are not necessarily student experiments and are flown in cannisters located in the payload bay. The sponsor of the chicken egg experiment is Kentucky Fried Chicken. It was originally manifested on 51-L, this one is a replacement. -- Elizabeth Nuchia Lockheed Engineering Sciences Company uunet!nuchat!eliz 2400 NASA Rd. 1, Houston, Texas 77258 (713) 334 6720 I don't speak for Lockheed or NASA, and vice versa.
sparks@corpane.UUCP (John Sparks) (03/14/89)
In article <218100013@s.cs.uiuc.edu>, carroll@s.cs.uiuc.edu writes: > > I saw a report recently that had a Get-Away-Special mission that was > sending up half of a set of ``identical'' chicken eggs, the other half staying > on the ground as a control group. While not exactly human development, I'd > say it's certainly a first step in such research. > > Alan M. Carroll "And then you say, Yes, I heard about this recently. I believe they went up on todays launch of Discovery [today is March 13, 1989]. But what I wonder about in these experiments is how do they know that the results they get back on the space eggs are the result of the micro-gravity environment and not some damage caused by the hi-g blast off and shaking? If you hatch scrambled eggs do you get scrambled chickens? :-) -- John Sparks // Amiga | {rutgers|uunet}!ukma!corpane!sparks \X/ UUCP | >> call D.I.S.K. @ 502/968-5401 thru 5406 << Chicken Little only has to be right once.
jack@cs.glasgow.ac.uk (Jack Campin) (03/14/89)
In all this attention to foetal development, the mother seems to been forgotten about. Since bones lose a lot of calcium in zero-G, and pregnancy requires a lot of calcium for the baby, there may well be serious problems for her; and some of the chemical fixes that might prevent decalcification are hazardous to the foetus. -- Jack Campin * Computing Science Department, Glasgow University, 17 Lilybank Gardens, Glasgow G12 8QQ, SCOTLAND. 041 339 8855 x6045 wk 041 556 1878 ho INTERNET: jack%cs.glasgow.ac.uk@nss.cs.ucl.ac.uk USENET: jack@glasgow.uucp JANET: jack@uk.ac.glasgow.cs PLINGnet: ...mcvax!ukc!cs.glasgow.ac.uk!jack
CHUNTER@UMAB.BITNET (Colin Hunter) (03/15/89)
From: m.cs.uiuc.edu!s.cs.uiuc.edu!carroll@uxc.cso.uiuc.edu writes > I saw a report recently that had a Get-Away-Special mission that was >sending up half of a set of ``identical'' chicken eggs, the other half >staying on the ground as a control group. While not exactly human >development, I'd say it's certainly a first step in such research. This sounds like an almost useless experiment if the intention is to extrapolate the results they will obtain to human foetal development. Earlier postings suggesting sending up pregnant rats were bad enough. There are just so many differences between human and rat embryology (gestational period, placental structure and brain development, to name but a few) that proposing to use rats as a suitable model for human pregnancy would give results that would be next to meaningless as far as humans are concerned. Pregnancy is such a species specific phenomenon that the only model I would lend any credence to as far as humans are concerned would be the chimpanzee. The egg experiment could be of use in investigating avian (and maybe eve reptillian) embryogenesis and would obviously be of interest if a colony wanted to maintain chickens as livestock for food. Beyond that, this idea is strictly for the birds.