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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Biochemical, physiological, and metabolic analysis of subjects in life support system on liquid food diets during space environment simulation
Earth life systems biochemical and physiological responses to space environment stresses like reduced gravity, noting muscle atrophy and coordination diminution
Spermatozoa observations and biochemical tests of semen in Macaca nemestrina monkey under study for orbital space flight
Biochemical and metabolic effects of exposure of mice to helium-oxygen atmosphere
Oxygen physiological and biochemical effects on Pseudomonas saccharophila, discussing sucrose uptake, lipid synthesis and polysaccharide formation
Thermodynamic properties of compounds of biochemical interest in aqueous solution
Structural and functional properties of phosphates in biochemical reactions, discussing linkages
Long term helium-oxygen atmosphere effects on rats and mice, investigating biochemical and metabolic changes
Biochemical molecular model for metabolic energy transition from mammalian organs to central nervous system
Chemical and biochemical space manufacturing using scaling laws and Gibbs functions
Six male subjects subsisting on a typical Apollo flight diet for five consecutive days were evaluated for changes in biochemical and physiological status. Laboratory examinations failed to demonstrate any significant changes of the kind previously attributed to weightlessness, such as in serum electrolytes, endocrine values, body fluid, or hematologic parameters.
The glucose content in blood and the lipid content in serum and tissues of dogs exposed to chronic radiation for 3 and 5 years were studied. In tissues of these animals, the concentration of soluble DNA and DNA contained in DNP was studied in the spleen, lymph node (deep cervical node) and bone marrow of thigh bones. Results indicate that chronic gamma irradiation significantly changes concentrations of glucose in the blood, and that of several lipids in serum and tissues. A reduction in the concentration of DNP in tested organs reflects changes in the relative number of cells with various nuclear cytoplasmic ratios; most pronounced changes in biochemical indices occur in dogs exposed to chronic gamma radiation in doses of 125 rad per year.
Continuous metabolic and endocrinic monitoring of Skylab crewmen established significant biochemical changes that varied in magnitude and direction but disappeared shortly after return to earth. These changes indicate adaptation by the body to the combined stresses of weightlessness. Transient changes in fluid and electrolyte metabolisms lead to the conclusion that a homeostasis condition had been achieved. Unstable states persisted in the metabolisms of bone mineral, protein, and carbohydrates.
The biochemical methods for determination of various parameters and factors during pre- and post-flight periods, as used by American and Soviet teams dealing with space flight medicine are compared. The emphasis is on the exchange of information on the study of the blood and urine content of space travelers before and after space flight. A series of electrolytic, enzymatic, and hormonal factors is discussed.
Some of the physiologic and biochemical changes that occur in mammalian skeletal muscle following denervation and reinnervation are considered and some comparisons are made with changes observed following altered motor function. The nature of the trophic influence by which nerves control muscle properties are discussed, including the effects of choline acetyltransferase and acetylcholinesterase and the role of the acetylcholine receptor.
Recent research on the remote sensing of forest leaf and canopy biochemical contents suggests that the shortwave IR region contains this information; laboratory analyses of dry ground leaves have yielded reliable predictive relationships between both leaf nitrogen and lignin with near-IR spectra. Attention is given to the application of these laboratory techniques to a limited set of spectra from fresh, whole leaves of conifer species. The analysis of Airborne Imaging Spectrometer data reveals that total water content variations in deciduous forest canopies appear as overall shifts in the brightness of raw spectra.
Findings on the connective tissue response to short-term space flight (12 days) are discussed. Specifically, data regarding the biochemical, biomechanical and morphological characteristics of selected connective tissues (humerus, vertebral body, tendon and skeletal muscle) of growing rats is given. Results are given concerning the humerus cortical bone, the vertebral bone, nutritional effects on bone biomechanical properties, and soft tense fiber connective tissue response.
Muscles of the hindlimb in the rat have been used to demonstrate the effects of unloading in weightlessness and in animal models used to mimic weightlessness. The vastus medialis (VM) is discussed here. Samples were obtained from rats exposed to weightlessness for 12 days in Cosmos 1887 (Experiment K-6-08, coordinated by Dr. V.S. Oganov). The principal objective of this study was to ascertain if the vastus medialis responded to 12 days of microgravity exposure. The loss in muscle mass is greatest, -43 percent, when comparing F vs B, and least, -13 percent, when comparing F vs. V. Taken at face value these differences may be misleading. Due to the variability of the muscle weight in the basal group, these muscle mass losses may be exaggerated. In terms of percent water, there were no differences between the flight and the control groups. In spite of the limited sample, researchers conclude that muscle mass changes in the VM are not significant. Although some of the morphological parameters suggest a small degree of atrophy in the vastus medialis, the biochemical analyses (protein, RNA and DNA) suggest that these may be minimal and functionally nonsignificant. The relatively similar CS and LDH activities of VM from F and various control groups, as well as the lack of difference in LPL activity between F and S rats, suggests that there is little or no effect on the oxidative or glycolytic function of this muscle. Since the VM is chiefly a mixed fast twitch muscle, these metabolic indices of energy production are relatively unchanged. The results of VM studies are in agreement with previous observations of another type II fast twitch muscle, the EDL, from SL-3 rats which did not respond markedly to weightlessness and whole body suspension.