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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 613 records · Page 34
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

Change in energy expenditure and brain and adrenal content of catecholamines in rats during muscular loading and hypokinesia

In male 1-7 month old rats, the growth and the protein content of skeletal muscles were higher than in female rats while the O2 consumption and the heart rate were lower. This is combined with reduction of the thyroid gland weight and of catecholamine content in adrenals at the age of 7 months. The development of male and female rats (1-7 month) under conditions of systematic muscular loads increases the growth tempo and protein of skeletal muscles and intensifies the degree of reduction of energy expenditure and the heart rate. This is accomplished by the greater reduction of relative weight of the thyroid gland and, at the age of 7 months, by reduction of the noradrenaline content in the brainstem. Hypodynamic conditions have the exact opposite effect.

Rozanova, V. D.↗
NASA NTRS1981

US plant and radiation dosimetry experiments flown on the Soviet satellite Cosmos 1129

Experiments included: 30 young male Wistar SPF rats used for wide range physiological studies; experiments with plants, fungi, insects, and mammalian tissue cultures; radiation physics experiments; a heat convection study; a rat embryology experiment in which an attempt was made to breed 2 male and 5 female rats during the flight; and fertile quail eggs used to determine the effects of spaceflight on avian embryogenesis. Specimens for US experiments were initially prepared at the recovery site or in Moscow and transferred to US laboratories for complete analyses. An overview of the mission focusing on preflight, on orbit, and postflight activities pertinent to the fourteen US experiments aboard Cosmos 1129 is presented.

Heinrich, M. R.↗
NASA NTRS1981

Experiment K-313: Rat and quail ontogenesis

The potential effects of spaceflight on the processes of mammalian fertilizaton, implantation and embryonic development are investigated. Five female and two male rats were placed together on Day 2 of the flight. By R+17, it was determined that both flight and synchronous females were not carrying normal pregnancies and three of the flight animals were laparotomized. The uterus and ovaries were processed for microscopic analyses. The two remaining flight females were allowed to recover from the exploratory operation, rebred with flight males and delivered normal litters. As a control for potential transplacental effects that might be interpreted as direct spaceflight effects, a series of fertilized Japanese quail (Coturnix japonica) eggs was flown on Cosmos 1129. Although all of the eggs were adversely impacted by an inflight failure of the incubator humidifier on flight Day 13, several embryos were able to progress to a developmental stage equivalent to that of a control 10-12 Day embryo.

Keefe, J. R.↗
NASA NTRS1980

Scaling of metabolic rate on body mass in small laboratory mammals

The scaling of metabolic heat production rate on body mass is investigated for five species of small laboratory mammal in order to define selection of animals of metabolic rates and size range appropriate for the measurement of changes in the scaling relationship upon exposure to weightlessness in Shuttle/Spacelab experiment. Metabolic rates were measured according to oxygen consumption and carbon dioxide production for individual male and female Swiss-Webster mice, Syrian hamsters, Simonsen albino rats, Hartley guinea pigs and New Zealand white rabbits, which range in mass from 0.05 to 5 kg mature body size, at ages of 1, 2, 3, 5, 8, 12, 18 and 24 months. The metabolic intensity, defined as the heat produced per hour per kg body mass, is found to decrease dramatically with age until the animals are 6 to 8 months old, with little or no sex difference. When plotted on a logarithmic graph, the relation of metabolic rate to total body mass is found to obey a power law of index 0.676, which differs significantly from the classical value of 0.75. When the values for the mice are removed, however, an index of 0.749 is obtained. It is thus proposed that six male animals, 8 months of age, of each of the four remaining species be used to study the effects of gravitational loading on the metabolic energy requirements of terrestrial animals.

Pace, N.↗
NASA NTRS1982

Body composition data from the rat subjects of Cosmos 1129 experiment K-316

The effects of 18.5 days of weightlessness on the body composition of young, growing, male laboratory rats were examined. Three groups of 5 rats each were examined. It is indicated that exposure of young, growing, male rats to 18.5 days of weightlessness produces: (1) no effect on the quantity of fat stored by the body; (2) a slight reduction in the quantity of fat free tissue laid down by the body; (3) a small reduction in the fraction of water contained by the fat free body mass; (4) a similar reduction in the fraction of water contained by the fat free skin and fat free carcass; (5) a shift in relative distribution of the total body water from skin to viscera; (6) a diminution in the fraction of extracellular water contained by the fat free body; (7) no effect on the fraction of total skeletal musculature contained by the fat free body, as indicated by body creatine content; (8) a sizeable reduction in the fraction of bone mineral contained by the fat free body, as calculated from body calcium content. The nature of the physiological changes induced by unloading from Earth gravity in the mammalian organism are illustrated.

Pace, N.↗
NASA NTRS1980

Psychological considerations in future space missions

Issues affecting human psychological adjustments to long space missions are discussed. Noting that the Shuttle flight crewmembers will not have extensive flight qualification requirements, the effects of a more heterogeneous crew mixture than in early space flights is considered to create possibilities of social conflicts. Routine space flight will decrease the novelty of a formerly unique experience, and the necessity of providing personal space or other mechanisms for coping with crowded, permanently occupied space habitats is stressed. Women are noted to display more permeable personal space requirements. The desirability of planning leisure activities is reviewed, and psychological test results for female and male characteristics are cited to show that individuals with high scores in both traditionally male and female attributes are most capable of effective goal-oriented behavior and interpersonal relationships. Finally, it is shown that competitiveness is negatively correlated with the success of collaborative work and the social climate of an environment.

Helmreich, R. L.↗
NASA NTRS1985

Challenges in the development of the shuttle extravehicular mobility unit

The development of the Shuttle extravehicular mobility unit (EMU) has required significant technology advances in the design of the astronaut life support system and space-suit assembly. The life support system and space-suit assemblies are integrated into a single system and optimized for the primary function of supporting astronaut extravehicular operations. Rather than accommodating a limited, male-only astronaut population, the EMU must satisfy size requirements for both males and females with a minimum of sized parts. In addition, the Shuttle EMU has been designed to implement Space Shuttle Program philosophy of long operating life and mission reuse capability to minimize program lifetime cost. The advancement in life support system and space-suit technology achieved by the development of the Shuttle extravehicular mobility unit (EMU) is illustrated by comparison with the requirements for and the design features of the Apollo EMU.

Mcmann, H. J.↗
NASA NTRS1985

Hypergravity induced prolactin surge in female rats

Acute initial exposure to hypergravity (HG) was previously found to induce prolonged diestrous in rats, which was followed by return to normal estrous cycling upon more prolonged exposure to continuous HG. Bromergocryptine was found to prevent this prolonged diestrous. In this study it is found that in female rats 20 h of 3.14 G exposure (D-1 1200 h until D-2 0800 h) can induce prolactin surge at D-2 1600 h. Shorter exposure time (8 h), or exposure during a different part of the estrous cycle (19 h: from D-1 0700 h until D-2 0200 h) could not elicit this prolactin surge. Similar exposure of male rats of HG did not alter significantly their prolactin levels. It is possible that the hypothalamus of male and female rats responds differently to stimulation by HG.

Megory, E.↗
NASA NTRS1986

Self-Alining Electrical Connector

Mating pair of insulators forces initial alinement of plug and socket. Male pins recessed behind one of alining insulators so they cannot touch female contacts alined. Contacts mate when coupling nut draws alined plug and socket together, depressing one of alining insulators against spring. Compressed spring provides tension on mated threads of assembly helping connector to resist loosening under vibration or shock. Arrangement prevents breakage or bending of male pins on conventional connectors when misalined contacts carelessly pressed together.

Swanic, A.↗
NASA NTRS1985

Physical, anthropometrical, and body composition characteristics of workers at Kennedy Space Center

At the Kennedy Space Center, workers are often exposed to cardiovascular and muscular stress in job-related activities which may require a high level of physical fitness in order to safely complete the work task. Similar tasks will be performed at other launch and landing facilities and in space for the Space Station. One such category includes workers who handle toxic propellants and must wear Self-Contained Atmospheric Protective Ensembles (SCAPE) that can weigh 56 lbs. with the air pack. These suits provide a significant physical challenge to many of the workers in terms of carrying this load while moving about and performing work. Furthermore, under some conditions, there is a significant thermal stress. The physical characteristics of these workers are, therefore, of consequence. The purpose of this study was to analyze the anthropometry, body composition, strength, power, endurance, flexibility, aerobic fitness, and blood variables of a representative sample of male KSC SCAPE workers and to compare them with characteristics of other male workers at KSC (total population N=110). Three separate comparisons were made.

Lasley, M. L.↗
NASA NTRS1985

Can pilots time-share better than non-pilots?

The time-sharing ability of 12 male pilots and 12 male college students ranging in age from 18-36 are evaluated and compared. The subjects performed five pairs of dual tasks with varying degrees of structural similarity; the test procedures are described. The time-sharing efficiency and resource allocation optimality of the subjects are analyzed. The data reveal that the pilots and students display similar time-sharing performance; the degree of time-sharing efficiency decreases and resource allocation optimality increases with an increasing degree of structural similarity between the time-shared tasks.

Tsang, P. S.↗
NASA NTRS1986

Evaluation of 9.5 PSIA as a suit pressure for prolonged extravehicular activity

A study was undertaken to determine if a pressure of 9.5 psia would aid against the occurrence of decompression sickness in both males and females (without prebreathing or stage decompression requirements) during a typical simulated extravehicular activity scenario. Twenty percent of the male subjects produced grades 1 and 2 bubbles while females did not produce bubble signals at all. It is concluded that a pressure of 9.5 psia can protect the astronaut from both formation of severe bubbling and development of bends symptoms when exposed to these study conditions.

Dixon, G. A.↗
NASA NTRS1987

Tube coupling device

A first annular ring of a tube coupling device has a keyed opening sized to fit around the nut region of a male coupling, and a second annular ring has a keyed opening sized to fit around the nut of a female coupling. Each ring has mating ratchet teeth and these rings are biased together, thereby engaging these teeth and preventing rotation of these rings. This in turn prevents the rotation of the male nut region with respect to the female nut. For tube-to-bulkhead locking, one facet of one ring is notched, and a pin is pressed into an opening in the bulkhead. This pin is sized to fit within one of the notches in the ring, thereby preventing rotation of this ring with respect to the bulkhead.

Myers, William N.↗
NASA NTRS1987

The effect of exercise on venous gas emboli and decompression sickness in human subjects at 4.3 psia

The contribution of upper body exercise to altitude decompression sickness while at 4.3 psia after 3.5 or 4.0 hours of 100% oxygen prebreathing at 14.7 psia was determined by comparing the incidence and patterns of venous gas emboli (VGE), and the incidence of Type 1 decompression sickness (DCS) in 43 exercising male subjects and 9 less active male Doppler Technicians (DT's). Each subject exercised for 4 minutes at each of 3 exercise stations while at 4.3 psia. An additional 4 minutes were spent monitoring for VGE by the DT while the subject was supine on an examination cot. In the combined 3.5 and 4.0 hour oxygen prebreathe data, 13 subjects complained of Type 1 DCS compared to 9 complaints from DT's. VGE were detected in 28 subjects compared to 14 detections from DT's. A chi-square analysis of proportions showed no statistically significantly difference in the incidence of Type 1 DCS or VGE between the two groups; however, the average time to detect VGE and to report Tyep 1 DCS symptoms were statistically different. It was concluded that 4 to 6 hours of upper body exercise at metabolic rates simulating EVA metabolic rates hastens the initial detection of VGE and the time to report Type 1 DCS symptoms as compared to DT's.

Conkin, Johnny↗
NASA NTRS1987

Hemolysis in runners as evidenced by low serum haptoglobin: Implications for preflight monitoring of astronauts

Hematological parameters and serum haptoglobin were examined in 21 male employees of the Kennedy Space Center who were at 3 levels of physical activity: 7 subjects regularly ran more than 40 km (25 miles) per week (Group I); 7 ran 13 to 24 km (8 to 15 miles) per week (II), and 7 were sedentary (III). Blood was drawn on a different day of the week for five weeks. Differences between day of the week, visit number, and activity level were examined. No differences were observed for day of week or visit number; thus mean values for each variable were calculated for each subject. Variables did not differ among groups. However, trends with level of training were observed in some critical variables. Hemoglobin (Hb) and hematocrit (Hct) conformed to a staircase effect with Group I (14.5 gm/dl and 41.3 percent) lower than Group III (15.1 gm/dl and 42.9 percent). Reticulocyte count was higher and haptoglobin levels lower in Group I (1.35% and 75.7 gm/dl) than Group III (.99 percent and 132.9 gm/dl), with haptoglobin for the high mileage Group I in the clinically abnormal range. Since haptoglobin binds free Hb following RBC destruction, these results suggest that intravascular hemolysis occurs in trained male runners. These results may have special meaning for astronauts training before long-duration spaceflights, since the further reduction in red blood cells which is reported to occur during spaceflight could become detrimental to their health and performance.

Owens, Joyce↗
NASA NTRS1988

Quick-disconnect inflatable seal assembly

A zero-leak cryogenic coupling includes a polymeric seal clamped to a male bayonet member with two pairs of tightening rings. The tightening rings threadably engage each other in respective pairs around tapered ends of the inflatable seal member so that a wedging action tightness the seal member about the male bayonet. Once in place, the seal may be inflated via an inflation port so that its expansion provides a pressure contact with the inside surface of a coaxial female member.

Kurt D Buehler↗
NASA NTRS1990

The susceptibility of rhesus monkeys to motion sickness

The susceptibility of rhesus monkeys to motion sickness was investigated using test conditions that are provocative for eliciting motion sickness in squirrel monkeys. Ten male rhesus monkeys and ten male Bolivian squirrel monkeys were rotated in the vertical axis at 150 deg/s for a maximum duration of 45 min. Each animal was tested in two conditions, continuous rotation and intermittent rotation. None of the rhesus monkeys vomited during the motion tests but all of the squirrel monkeys did. Differences were observed between the species in the amount of activity that occurred during motion test, with the squirrel monkeys being significantly more active than the rhesus monkeys. These results, while substantiating anecdotal reports of the resistance of rhesus monkeys to motion sickness, should be interpreted with caution because of the documented differences that exist between various species with regard to stimuli that are provocative for eliciting motion sickness.

Corcoran, Meryl L.↗
NASA NTRS1990

System for connecting fluid couplings

A system for mating fluid transfer couplings is constructed having a male connector which is provided with a pair of opposed rollers mounted to an exterior region thereof. A male half of a fluid transfer coupling is rotatably supported in an opening in an end of the connector and is equipped with an outwardly extending forward portion. The forward portion locks into an engagement and locking region of a female half of the fluid transfer coupling, with female half being rotatably supported in a receptacle. The receptacle has an opening aligned with locking region, with this opening having a pair of concentric, annularly disposed ramps extending around an interior portion of opening. These ramps are inclined toward the interior of the receptacle and are provided with slots through which rollers of the connector pass. After the connector is inserted into the receptacle (engaging forward portion into engagement region), relative rotation between the connector and receptacle causes the rollers to traverse ramps until the rollers abut and are gripped by retainers. This axially forces the forward portion into locked, sealed engagement with the engagement region.

Cody, Joseph C.↗