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An optimized index of human cardiovascular adaptation to simulated weightlessness
IEEE Transactions on Biomedical Engineering, 1996Prolonged exposure to weightlessness is known to produce a variety of cardiovascular changes, some of which may influence the astronaut's performance during a mission. In order to find a reliable indicator of cardiovascular adaptation to weightlessness, we analyzed data from nine male subjects after a 24-hour period of normal activity and after a ...
Mao Wang +4 more
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Effect of a Simulated Weightlessness Model on the Production of Rat Interferon
Journal of Interferon Research, 1982A rat model simulating some aspects of weightlessness was used to determine whether simulated weightlessness might alter interferon production. The optimum time for in-vivo induction of alpha/beta interferon (alpha/beta-IFN) by polyriboinosinic-polyribocytidylic acid was determined to be four hours in normal, mature rats.
G, Sonnenfeld +3 more
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[The effect of weightlessness and simulated weightlessness on the expression of genes].
Hang tian yi xue yu yi xue gong cheng = Space medicine & medical engineering, 2003The research results of the relationship between gene expression and weightlessness or simulated weightlessness were studied. The influence of weight on the expression of genes in central nervous system were summarized in three aspects. It can be concluded that the expression of genes in central nervous system were precisely regulated by weight. It was
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Decision making after 50 days of simulated weightlessness
Brain Research, 2009By restricting physical activity levels, the bed rest simulation of weightlessness could be associated with changes in prefrontal cortex functioning that manifest as cognitive decrements, particularly for executive cognitive functions. We aimed to determine if performance on an executive function task was indeed affected by bed rest.
Darren M, Lipnicki +3 more
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Urinary adrenaline and noradrenaline response to simulated weightless state
American Journal of Physiology-Legacy Content, 1964Sixteen normal subjects were placed in a simulated weightless state, i.e., water immersion. After 6 hr of water immersion, urine samples were collected and bio-assayed for adrenaline and noradrenaline. The excretion of adrenaline was moderately increased ( P < 0.15 > 0.10), possibly related to the anxiety associated with the immersion.
M, GOODALL, M, MCCALLY, D E, GRAVELINE
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Effects of spaceflight and simulated weightlessness on longitudinal bone growth
Bone, 2000Indirect measurements have suggested that spaceflight impairs bone elongation in rats. To test this possibility, our laboratory measured, by the fluorochrome labeling technique, bone elongation that occurred during a spaceflight experiment. The longitudinal growth rate (LGR) in the tibia of rats in spaceflight experiments (Physiological Space ...
J D, Sibonga +6 more
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Plasma viscosity elevations with simulated weightlessness.
Aviation, space, and environmental medicine, 1986Bed rest studies which simulate weightlessness have demonstrated marked changes in the state of hydration of subjects as well as decrements in aerobic capacity. These two phenomena may be linked through increases in blood viscosity which is altered by a loss of free water and which, in turn, influences blood flow needed for aerobic muscular work.
D G, Martin +4 more
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Integrated regulation in response to simulated weightlessness.
Hang tian yi xue yu yi xue gong cheng = Space medicine & medical engineering, 1997To investigate physiological effects of tail suspension, Ca2+ concentration, immune factors, erythrocyte rheological properties, and growth hormone were determined in rats suspended for 15 and 30 d. The results showed that inhibitory changes of both local factors (proteins secreted by bone cell, Ca(2+)-ATPase in sarcoplasmic reticium) and integrated ...
G, Yang +5 more
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Simulated weightlessness: effects of bioenergetic balance.
Aviation, space, and environmental medicine, 1980As a prelude to a flight experiment, an attempt was made to separate energy requirements associated with gravity from all other metabolic needs. The biological effects of weightlessness were simulated by suspending animals in a harness so that antigravity muscles were not supporting the body.
J P, Jordan +5 more
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Neuromuscular adaptation to actual and simulated weightlessness.
Advances in space biology and medicine, 1995The chronic "unloading" of the neuromuscular system during spaceflight has detrimental functional and morphological effects. Changes in the metabolic and mechanical properties of the musculature can be attributed largely to the loss of muscle protein and the alteration in the relative proportion of the proteins in skeletal muscle, particularly in the ...
V R, Edgerton, R R, Roy
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