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Human Autonomic Responses to Actual and Simulated Weightlessness
The Journal of Clinical Pharmacology, 1991Orthostatic dysfunction occurs after exposure to microgravity, and is not completely understood. The authors developed a device for stimulating carotid baroreceptors to test the hypothesis that exposure to microgravity leads to impairment of arterial baroreflex mechanisms.
Janice M. Fritsch, Dwain L. Eckberg
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Chapter 2 Neuromuscular Adaptation to Actual and Simulated Weightlessness
1994The 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, Roland R. Roy
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Effects of Simulated Weightlessness on Bone Mineral Metabolism
Endocrinology, 1984Space flight and bedrest result in a negative calcium balance and osteopenia. The mechanisms underlying these events are not well understood. In particular, it is not clear whether systemic or local factors are preeminent in mediating the effects of gravity on bone mineral content.
Daniel D. Bikle +2 more
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Simulated Weightlessness in the Design and Exploitation of a NMR-Compatible Bioreactor
Biotechnology Progress, 2004Mammalian cells cultured in simulated weightlessness take advantage of a favorable environment, experiencing low shear stress and reduced turbulence. NMR spectroscopy allows the on-line noninvasive monitoring of cell growth and metabolism. With this in mind, we developed a novel bioreactor that fits into a NMR instrument and in which the simulated ...
Bradamante S, Barenghi L, Villa A
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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.
Emily R. Morey +3 more
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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 ...
Michael Mao Wang +4 more
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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.
Daniel L. Belavy +3 more
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1986
The phenomenon of gravitation is characterized by the mutual attraction of any two bodies. The universal character of gravitation was first recognized by Isaac Newton who found the well-known law for the attraction force F acting between two mass points or homogeneous spherical bodies $$\rm F\, = \,\gamma Mm/R^2 $$ (3.1) M, m are the masses ...
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The phenomenon of gravitation is characterized by the mutual attraction of any two bodies. The universal character of gravitation was first recognized by Isaac Newton who found the well-known law for the attraction force F acting between two mass points or homogeneous spherical bodies $$\rm F\, = \,\gamma Mm/R^2 $$ (3.1) M, m are the masses ...
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[Study of temperature homeostasis in real and simulated weightlessness].
Fiziologiia cheloveka, 2002The analysis of the temperature (T) reaction of the body of healthy humans was carried out using the results of investigations with the thermometry technique under antiorthostatic hypokinesia (ANOH) (38 males in the studies of 14- to 49-day duration, eight females, 120 days), isolation in a regenerated gas environment (six males, 90 to 135 days), suit ...
I. M. Larina, N. G. Lakota
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Effects of simulated weightlessness on bone properties in rats
Journal of Biomechanics, 1990Abstract This paper addresses two questions: (1) are reductions in bone apposition rate during disuse due to increased periods of ‘resting’ during bone formation? and (2) are diaphyseal strength changes due to disuse caused by changes in the quality as well as the quantity of the bone matrix?
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