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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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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Pulmonary Edema and Plasma Volume Changes in Dysbarism

Two groups of anesthetized, fasted pigs were utilized. One group of 13 animals (8.5 to 16.6 kilograms) was exposed to a high-pressure environment, and the other group of eight animals (6.9 to 20.0 kilograms) constituted the control group. The experimental group was subjected to an atmosphere of 90 percent nitrogen and 10 percent oxygen at a pressure of 50 psig for 30 minutes and then decompressed at a rate 10 psi/min. Plasma volumes, using both iodine-125-tagged-albumin and chromium-51-tagged-cell dilution techniques, were measured before, immediately after, and at 30 and 60 minutes after decompression. Aortic and right-ventricular systolic pressures were also recorded. At 60 minutes after decompression, blood samples were taken, the animals were sacrificed, and the water content of the lungs, kidneys, livers, and spleens was estimated by measuring tissue wet weight and dry weight. Protein extravasation and tissue blood volumes were determined by measuring the iodine-125-tagged-albumin and chromium-51-tagged-cell spaces in homo-genates of the organs under investigation.

Joki, J. A.↗
NASA NTRS1970

A computer-controlled scintiscanning system and associated computer graphic techniques for study of regional distribution of blood flow.

Two methods whereby a digital computer may be used to regulate a scintiscanning process are discussed from the viewpoint of computer input-output software. The computer's function, in this case, is to govern the data acquisition and storage, and to display the results to the investigator in a meaningful manner, both during and subsequent to the scanning process. Several methods (such as three-dimensional maps, contour plots, and wall-reflection maps) have been developed by means of which the computer can graphically display the data on-line, for real-time monitoring purposes, during the scanning procedure and subsequently for detailed analysis of the data obtained. A computer-governed method for converting scintiscan data recorded over the dorsal or ventral surfaces of the thorax into fractions of pulmonary blood flow traversing the right and left lungs is presented.

Coulam, C. M.↗
NASA NTRS1972

Pattern of filling in the pulmonary capillary bed.

Artificially ventilated and perfused dog lungs were rapidly frozen under various physiological conditions. In 2-micron-thick sections the number of red blood cells (RBCs) per 10-micron length of alveolar septum was counted. Under conditions in which alveolar pressure exceeded venous pressure, variation in RBC concentration within areas supplied by single arterioles accounted completely for variation between areas supplied by different arterioles. Except at very high perfusion pressures when venous pressure exceeded alveolar pressure, there was no significant correlation between RBC concentrations of pairs of adjacent septa.

Warrell, D. A.↗
NASA NTRS1972

Effects of diffusion impairment on O2 and CO2 time courses in pulmonary capillaries.

Simultaneous time courses for O2 and CO2 exchange along the capillary have been calculated for homogeneous lungs, allowing for O2-CO2 interactions, dissolved O2, and chemical reaction rates. As diffusing capacity (Dl) was reduced, the transfer of CO2 and O2 was impaired by similar amounts, in spite of the 20-fold greater diffusing capacity for CO2. The reason why CO2 is affected so much is that the slope of the content against partial pressure is so much greater in blood than tissue for this gas. Because of the shapes of their respective dissociation curves, O2 transfer was most affected at normal ventilation-perfusion ratios, whereas CO2 was most affected at high ratios. Exercise exaggerated the impairment of transfer of both gases.

Wagner, P. D.↗
NASA NTRS1973

Barometric pressure

The effects of alterations in barometric pressure on human beings are described. Human tolerances for gaseous environments and low and high barometric pressure are discussed, including effects on specific areas, such as the ear, lungs, teeth, and sinuses. Problems due to trapped gas within the body, high dynamic pressures on the body, and blasts are also considered.

Billings, C. E.↗
NASA NTRS1973

Respiratory system

The general anatomy and function of the human respiratory system is summarized. Breathing movements, control of breathing, lung volumes and capacities, mechanical relations, and factors relevant to respiratory support and equipment design are discussed.

Bartlett, R. G., Jr.↗
NASA NTRS1973

Recent NASA aerospace medicine technology developments

Areas of life science are being studied to obtain baseline data, strategies, and technology to permit life research in the space environment. The reactions of the cardiovascular system to prolonged weightlessness are also being investigated. Particle deposition in the human lung, independent respiratory support system, food technology, and remotely controlled manipulators are mentioned briefly.

Jones, W. L.↗
NASA NTRS1973

Studies of the effects of gravitational and inertial forces on cardiovascular and respiratory dynamics

The current status and application are described of the biplane video roentgen densitometry, videometry and video digitization systems. These techniques were developed, and continue to be developed for studies of the effects of gravitational and inertial forces on cardiovascular and respiratory dynamics in intact animals and man. Progress is reported in the field of lung dynamics and three-dimensional reconstruction of the dynamic thoracic contents from roentgen video images. It is anticipated that these data will provide added insight into the role of shape and internal spatial relationships (which is altered particularly by acceleration and position of the body) of these organs as an indication of their functional status.

Ritman, E. L.↗
NASA NTRS1973

Detection techniques for tenuous planetary atmospheres

The research performed during this period is reported. The studies discussed include: dust grinding and electrification, effects of metallic impurities on exoelectron emission, the connection between the charge acquired by the dust and the effect of the dust on human lung tissue. A list of publications generated by this research is included.

Hoenig, S. A.↗
NASA NTRS1973

Reactions of singlet oxygen with pine pollen.

A study was initiated to determine whether viable atmospheric particles such as plant pollens and fungal spores containing unsaturated lipids can interact with singlet oxygen to give oxygenated products that are potentially toxic. The results obtained confirm that surface and near surface components of common viable particulate matter in the atmosphere may be subject to rapid oxidation by singlet oxygen, leading to products which are probably allylic hydroperoxides. In connection with increasing atmospheric pollution, it is important to note that materials toxic to mammalian lung tissue may be oxidatively produced on the surfaces of viable particulate matter.

Dowty, B.↗
NASA NTRS1973

Methods for study of cardiovascular adaptation of small laboratory animals during exposure to altered gravity

Several new techniques are reported for studying cardiovascular circulation in small laboratory animals kept in metabolic chambers. Chronical cannulation, miniaturized membrane type heart-lung machines, a prototype walking chamber, and a fluorocarbon immersion method to simulate weightlessness are outlined. Differential hypothermia work on rat cancers provides localized embedding of radionuclides and other chemotherapeutical agents in tumors and increases at the same time blood circulation through the warmed tumor as compared to the rest of the cold body. Some successful clinical applications of combined chemotherapy and differential hypothermia in skin cancer, mammary tumors, and brain gliomas are described.

Popovic, V.↗
NASA NTRS1973

Ultrastructural pathogenesis of lesions produced by exposure to oxygen difluoride with correlative light microscopy

The lungs of rats exposed to OF2 were examined by light and electron microscopy. The exposures were for 30 to 60 minutes to an average of 4.5 ppm OF2, the minimal lethal dose. Animals were sacrificed after 30 (group 1) and 60 minutes (group 2) exposure and 1 (group 3) and 2 (group 4) hours following 60 minutes exposure. Mild gross changes were observed in groups 3 and 4, but no light microscopic lesions were found. Alterations were noted in all four groups using electron microscopy. These were mostly indicative of fluid change and consisted of blebbing of the endothelial and epithelial layers of the alveolocapillary wall and rarification of the cytoplasm of these cells. The lamellar bodies of the Type II cells showed an increasing and consistent loss of matrix structure and density. These fine structural changes increased in quantity and severity as time of exposure or post-exposure period increased. (Modified author abstract)

Harrison, G.↗
NASA NTRS1972

Effects of geophysical extra-terrestrial and terrestrial physical stimuli on living organisms - Effects of gravity fields on living organisms

The biologic effects of greatly reduced gravity resulting from space flight are examined. Aspects of U.S. space biology during the period from 1960 to 1972 are discussed, giving attention to the Discoverer satellites, the Gemini series, the OV1-4 satellite, the biosatellite project, the orbiting frog otolith experiment, and the Apollo program. Other studies considered are related to the effects of galactic particles on nonproliferating cells, a recoverable tissue culture experiment, cell cycle maintenance in human lung cells, and effects of space flight on circadian rhythms. Viking will land on the planet Mars in 1975 in search for life forms.

Saunders, R. J. F.↗
NASA NTRS1974

The response of single human cells to zero gravity

The SO15 experiment was designed to extend observations of the effects of zero-gravity to living human cells during and subsequent to a 59-day flight on Skylab 3. A strain of diploid human embryonic lung cells, WI-38, was chosen for this purpose. The studies were concerned with observations designed to detect the effects of zero-gravity on cell growth rates and on cell structure as observed by light microscopy, transmission and scanning electron microscopy and histochemistry. Studies of the effects of zero-gravity on the cell function and the cell cycle were performed by time lapse motion picture photography and microspectrophotometry. Subsequent study of the returned living cells included karotyping, G- and C-banding, and analyses of the culture media used. Some of the living cells returned were banked by deep freeze techniques for possible future experiments.

Montgomery, P. O., Jr.↗
NASA NTRS1974

Determination of cardiac size from chest roentgenograms following Skylab missions

Decreased cardiothoracic transverse diameter ratios following Mercury, Gemini and Apollo space flights have been reported previously. To evaluate further changes in cardiac size, standard posteroanterior chest films in systole and diastole were obtained before flight and within a few hours after recovery on each of the Skylab astronauts. Postflight chest X-rays were visually compared to the preflight roentgenograms for possible changes in pulmonary vasculature, lung parenchyma, bony or soft tissue structures. From these roentgenograms the following measurements were obtained: cardiac and thoracic transverse diameters, cardiothoracic transverse diameter ratio, cardiac area from the product of both diagonal diameters, cardiac silhouette area by planimetry, thoracic cage area and cardiothoracic area ratio. The postflight frontal cardiac silhouette sizes were significantly decreased when compared with the respective preflight values (P0.05 or 0.01). The observed changes are thought to be related to postflight decrease in the intracardiac chamber volume.

Nicogossian, A. E.↗
NASA NTRS1974

Development and creation of conditions for the radiation of biological objects with high energy protons

Depth distribution of an absorbed proton radiation dose was studied by both calculation and experimental methods on a cylindrical, homogeneous plexiglass phantom that represented the geometric form of a dog. The basis of the heterogeneous phantom was the natural skeleton of a dog, muscle tissue was simulated by a mixture of paraffin and silica filler, and lung tissue by gelatine capsules.

Popov, V. P.↗
NASA NTRS1974

Total body calcium analysis

A technique to quantitate total body calcium in humans is developed. Total body neutron irradiation is utilized to produce argon 37. The radio argon, which diffuses into the blood stream and is excreted through the lungs, is recovered from the exhaled breath and counted inside a proportional detector. Emphasis is placed on: (1) measurement of the rate of excretion of radio argon following total body neutron irradiation; (2) the development of the radio argon collection, purification, and counting systems; and (3) development of a patient irradiation facility using a 14 MeV neutron generator. Results and applications are discussed in detail.

Lewellen, T. K.↗