X-ray density changes in the human heel during bed rest
Recumbency effect on human heel bone density during bed rest using X rays
Hurxthal, L. M.↗
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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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Biosynthesis of heme in the vitamin E-deficient rat
Heme biosynthesis defect in vitamin E-deficient rats affecting bone marrow synthesis of delta- aminolevolinic acid and liver formation of porphobilinogen
Brooks, S. K.↗
Skeletal status and soft tissue composition of astronauts. Determination of body composition in vivo Progress report, 15 Jun. 1970 - 15 Jun. 1971
Measuring instruments for in vivo bone mineral content and body composition measurement
Cameron, J. R.↗
Hypogravic and Hypodynamic Environments
Conference on aerospace environments, manned space flight, weightlessness simulation, musculoskeletal and cardiovascular systems, bone loss, mineral metabolism, and hematology
Mc Cally, M.↗
Hormonal Control of Calcium Metabolism
Assays of hormonal control of calcium and bone metabolism
Potts, J. T., Jr.↗
Peptide Hormones in Urine
Effects of space flight on bone metabolism investigated by analyzing peptide hormones in urine
Nelson, D. H.↗
Determining body composition by radiation absorption spectrometry
Fat lean cellular and bone mineral mass determination in living bodies, using radiation absorption spectrometry
Cameron, J. R.↗
Hard tissue as a composite material. I - Bounds on the elastic behavior
Elastic behavior of bone as two phase composite material, using ultrasonically measured hydroxyapatite moduli
Katz, J. L.↗
Primate restraint system for studies of metabolic responses during recumbency
Primate restraint harness of nylon jacket and cotton cot on aluminum frame padded seat for bone resorption and calcium metabolism studies
Howard, W. H.↗
Methods of space radiation dose analysis with applications to manned space systems
The full potential of state-of-the-art space radiation dose analysis for manned missions has not been exploited. Point doses have been overemphasized, and the critical dose to the bone marrow has been only crudely approximated, despite the existence of detailed man models and computer codes for dose integration in complex geometries. The method presented makes it practical to account for the geometrical detail of the astronaut as well as the vehicle. Discussed are the major assumptions involved and the concept of applying the results of detailed proton dose analysis to the real-time interpretation of on-board dosimetric measurements.
Langley, R. W.↗
Dosimetry for radiobiological studies of the human hematopoietic system
A system for estimating individual bone marrow doses in therapeutic radiation exposures of leukemia patients was studied. These measurements are used to make dose response correlations and to study the effect of dose protraction on peripheral blood cell levels. Three irradiators designed to produce a uniform field of high energy gamma radiation for total body exposures of large animals and man are also used for radiobiological studies.
Beck, W. L.↗
Improvements of magnetic heads through the use of new and refined core materials
A process for making ferromagnetic films with high permeability and development of the technology for fabricating a magnetic head using these films are reported. An interim head was successfully built, tested, and delivered for evaluation and a process for sputtering high permeability films has been developed. Two heads with deposited pole tips have been tested and delivered. One had a 0.0001 inch gap and the other a 0.0003 inch gap. Both heads were boned with epoxy but served to test the geometry of the head design.
Source record↗
On the anisotropic elastic properties of hydroxyapatite.
Experimental measurements of the isotropic elastic moduli on polycrystalline specimens of hydroxyapatite and fluorapatite are compared with elastic constants measured directly from single crystals of fluorapatite in order to derive a set of pseudo single crystal elastic constants for hydroxyapatite. The stiffness coefficients thus derived are given. The anisotropic and isotropic elastic properties are then computed and compared with similar properties derived from experimental observations of the anisotropic behavior of bone.
Katz, J. L.↗
Inhaled ozone as a mutagen. II - Effect on the frequency of chromosome aberrations observed in irradiated Chinese hamsters.
Exposure-adjusted break frequencies for chromosome aberrations produced in Chinese hamster circulating blood lymphocytes were the quantitative indicator of damage from 5 hrs of exposure to X-radiation and/or to ozone. Radiation produced 5.51 x 0.0001 breaks/cell rad for cells withdrawn 2 weeks after exposure, a reasonable value when compared with data from in vivo exposure of human lymphocytes and Chinese hamster bone marrow cells. Animals exposed to the two agents simultaneously exhibited more than 70% of the total breaks anticipated assuming the expected equal contributions to be additive. Extending to humans, at presently permitted levels, exposure to ozone would be much more detrimental than exposure to radiati*n.
Zelac, R. E.↗
Erythropoietic radiosensitivity of the rat during altitude acclimatization.
The effect of a sublethal dose (300 R) of X-radiation upon the erythropoietic system of the rat, during 60-day acclimatization to moderate hypoxia (3,800 m altitude), was studied. Past work has shown that hypoxic animals are damaged less by radiation than animals irradiated in a normal environment; therefore, it was postulated that if, after acclimatization to hypoxia the bone marrow oxygen tension returns to sea-level values, these animals should suffer radiation damage equivalent to animals at sea level. The principal parameters followed were the rate of depletion of injected Fe-59 from the plasma of chronically catheterized rats, and its subsequent reappearance in the circulating erythrocytes. After 20 days of acclimatization, both parameters for altitude-irradiated animals returned to the values of animals irradiated at sea level, previously having reflected increased erythropoiesis. In altitude nonirradiated animals the parameters indicated erythropoietic stimulation persisting up to 45 days acclimatization. The protective effect of the hypoxia on the stem cells vanished during acclimatization, presumably as cellular oxygen tension rose.
Gaugl, J. F.↗
Artificial limb connection
Connection simplifies and eases donning and removing artificial limb; eliminates harnesses and clamps; and reduces skin pressures by allowing bone to carry all tensile and part of compressive loads between prosthesis and stump. Because connection is modular, it is easily modified to suit individual needs.
Owens, L. J.↗
New tooth enamel from brushite crystals
Appropriate nutrient gel solution could be used to precipitate brushite, which becomes hydroxyapatite, mineral found in bones and teeth. Gel can be made from sodium metasilicate and phosphoric acid, or gelatin, or other organic materials that polymerize in presence of acid to get gelantinous medium.
Rubin, B.↗
Blood volume and red cell life span (M113), part C
Prechamber, in-chamber, and postchamber blood samples taken from Skylab simulation crewmembers did not indicate significant shortening of the red cell life span during the mission. This does not suggest that the space simulation environment could not be associated with red cell enzyme changes. It does show that any changes in enzymes were not sufficiently great to significantly shorten red cell survival. There was no evidence of bone marrow erythropoetic suppression nor was there any evidence of increased red cell destruction.
Johnson, P. C., Jr.↗