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Evaluation of the three-dimensional clinostat as a simulator of weightlessness
Planta, 1997Concerns regarding the reliability of slow-and fast-rotating uni-axial clinostats in simulating weightlessness have induced the construction of devices considered to simulate weightlessness more adequately. A new three-dimensional (3-D) clinostat equipped with two rotation axes placed at right angles has been constructed. In the clinostat, the rotation
Seiichiro Kamisaka +4 more
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Changes of brain response induced by simulated weightlessness
Acta Astronautica, 1992The characteristics change of brain response was studied during 15 degrees head-down tilt (HDT) comparing with 45 degrees head-up tilt (HUT). The brain responses evaluated included the EEG power spectra change at rest and during mental arithmetic, and the event-related potentials (ERPs) of somatosensory, selective attention and mental arithmetic ...
Zhiqiang Guan, Jinhe Wei, Gongdong Yan
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Effects of simulated weightlessness on rat osteocalcin and bone calcium [PDF]
American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 1989 Some of the musculoskeletal changes that occur in growing rats during spaceflight are simulated by a model that selectively unloads the hindlimbs while maintaining normal weight bearing on the forelimbs. Using this model we studied the response of mineral and the mineral-binding protein osteocalcin (OC) in the third lumbar vertebra (L3) and the ...
Emily Morey-Holton +4 more
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Effects of muscle electrostimulation during simulated weightlessness
Acta Astronautica, 1975In a 45-day experiment test subjects were exposed to bed rest with their heads down at -4 degrees C. Twice a day their muscles of the stomach, back, femur, and shin were stimulated with electric current for 25-30 min. The value of muscle tension was close to their maximum voluntary contraction.
L.I. Kakurin +3 more
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Skeletal abnormalities in rats induced by simulated weightlessness
Metabolic Bone Disease and Related Research, 1982A hypokinetic model has been developed which attempts to simulate the weightlessness experienced during space flight. Male rats (approximately 130 g) were suspended from the model with a head-down tilt for a two-week period. Total mechanical unloading of the hind limbs and partial unloading of the fore limbs occurred.
E. R. Morey, T. J. Wronski
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Simulated weightlessness for the ontogenesis of the otolith organ
Die Naturwissenschaften, 1968Abstract : The critical phase of the otolith-organ-ripening within the embryo was used in a simulation experiment by setting frog eggs (Rana temporaria) and toad eggs (Bufo bufo) near the center of a rotating system with a horizontal axis. The experiment speeds were 100 and 160 r.p.m.; the eggs and tadpoles were subjected to maximal centripetal forces ...
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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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