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It is shown that on days with frontal activity in the atmosphere the levels of fibrinolysis and fibrinogenolysis are increased. The reactions of fibrinolysis and fibrinogenolysis to the passage of warm and cold fronts varies with the season of the year.
The complexity of direct reading and passive dosimeters for monitoring radiation is studied to strike the right balance of compromise to simplify the monitoring procedure. Trapped protons, tissue disintegration stars, and neutrons are analyzed.
Methods for metabolic fingerprinting of pathogenic oral bacteria were developed and the effects of Skylab missions on salivary electrolyte levels were studied. High resolution gas liquid chromatographic (GLC) and pyrolysis-GLC procedures were used to obtain metabolic profiles of closely related bacteria associated with dental caries and periodontal disease. It was found that the GLC procedures provide a practical and reproducible means of obtaining metabolic markers for identifying closely related strains of these organisms. Fractions of stimulated whole saliva samples from the prime and back-up crews of the three Skylab missions were used to measure salivary electrolyte concentrations. All the electrolytes previously reported as having increased in urine and feces during the missions were assessed. Sodium, potassium, calcium, magnesium, phosphorous and chloride were studied. A decrease in sodium and an increase in magnesium were observed, but the mineral imbalances attributable to the mission-related increases in urinary electrolytes were not detected.
Liquid-cooled garments (LCG) have been developed which utilize liquid-cooled modules rather than the network of tygon tubing typical of Apollo LCG's. The ultra-thin, heat-sealed, polyurethane modules are situated over the body to cover 50 percent of the body surface area with special emphasis on the 'working' muscles and the head-neck area. These garments are being designed specifically for industrial and biomedical uses, such as: a head-neck cooling system which is being tested for race-car drivers, tractor drivers, truck drivers, or a head-neck cooling system tested for the reduction of the scalp hair loss which normally accompanies cancer treatments. A combined head-neck and thorax unit is being developed for use during mine distaster rescue operations, and for other hazardous hot applications. Finally applications for head-neck and partitional cooling are anticipated for military pilots, tank drivers, and heavy equipment operations.
Methods of predicting the state of health and human efficiency during space flight are discussed. Diversity of reactions to the same conditions, development of extrapolation methods of prediction, and isolation of informative physiological indexes are among the factors considered.
A typical flight profile for the Space Shuttle is reviewed, and the operation of the Spacelab, as well as deployment of a satellite from the Shuttle, is considered. Selection of crews for a Space Shuttle mission, which may include as many as four payload specialists, is also discussed. Since medical requirements and flight training standards need not be as high for payload specialists as for the three members of the flight crew, the Shuttle may provide an opportunity for many scientists to perform experiments in space. Investigations of the critical opalescence of fluids and laser holography are proposed for Shuttle missions; X-ray astronomy is another likely candidate for inclusion in the program.
The paper describes how observation of Uranus at far-red wavelengths during the planet's occultation of a star 3.5 magnitudes fainter led to the discovery of five rings surrounding the planet. Decreases in brightness occurring before the scheduled occultation were detected at the Perth Observatory near Bickley, Western Australia, and these decreases remained inexplicable until a study of the records showed a symmetric pattern before and after occultation by the planet. The Perth records support the planetary ring interpretation even though the planet's shadow could not be observed at Perth.
Small light-powered meter measures accumulated radiation in ultraviolet or other selected regions. Practical advantages are device's low cost, small size, accuracy, and adaptability to specific wave-band measurements. Medical applications include detection of skin cancer, vitamin D production, and jaundice. Dosimeter also measures sunlight for solar energy designs, agriculture and meteorology, and monitors stability of materials and environmental and occupational lighting.
Voice channel communication between low power mobile stations dispersed over a large area is provided by a system which includes a geostationary satellite utilizing a large UHF antenna that can receive a transmission from a caller and retransmit it over any one beam of a matrix of narrow beams, so the chosen beam covers an area in which a designated called party is located. A single up-link control channel occupying a narrow frequency band, can be utilized to receive dial up signals from a caller, and another single down link control channel can be utilized to ring up the called party located anywhere within the continental United States. The satellite antenna includes a matrix of feed horns that not only direct the beams in a controlled matrix onto the area of the continental United States, but also permit detection of the region from which the caller's signal is transmitted and the region from which the called party's answer is received, to enable the interconnection of signals received from these two regions. The system is particularly useful for rural areas.
Innovations in health care using aerospace technologies are described. Voice synthesizer and voice recognition technologies were used in developing voice controlled wheel chairs and optacons. Telephone interface modules are also described.
The satellite system requires the use of a large satellite antenna and spacecraft array power of about 12 kW or more depending on the operating frequency. Technology developments needed include large offset reflector multibeam antennas, satellite electrical power sybsystems providing greater than 12 kW of power, signal switching hardware, and linearized efficient solid state amplifiers for the satellite-aided mobile band. Presently there is no frequency assignment for this service, and it is recommended that an allocation be pursued. The satellite system appears to be within reasonable extrapolation of the state of the art. It is further recommended that the satellite-aided system spacecraft definition studies and supporting technology development be initiated.
A 15 minute orthostatic test was performed on healthy male volunteers under conditions of catheterization of the right ventricle of the heart and the radial (or brachial) artery before and after 5 day bedrest in an antiorthostatic position of the body (with the foot of the bed raised 4.5 degrees). The change to a vertical position after immobilization was attended by a more marked increase in the rate of cardiac contractions, an increase of max dp/dt pressure in the right ventricle, and a decrease of cardiac and stroke indices. The decrease of the cardiac index was compensated for, to a certain measure, by a further increase in the extraction and utilization of O2 by the tissues. The arterial blood pH did not change essentially, while the decrease in pCO2 and content of standard bicarbonate was more marked.
The right parts of the heart and the radial artery were catheterized in healthy male volunteers before and 5 days after strict bedrest in antiorthostatic position of the body (-4.5 deg). After immobilization, most values of central circulation showed no essential changes; the only exceptions were indicates characterizing the inotropic myocardial condition. A shift in the direction of acidosis of a mixed character was noted in mixed venous blood, the beta lipoprotein content increased. A decrease in the arteriovenous difference in oxygen was encountered in blood draining from the heart (from the coronary sinus).
The influence of group dynamics on the capability of aircraft crew members to make full use of the resources available on the flight deck in order to maintain flight safety is discussed. Instances of crewmembers withholding altimeter or heading information from the captain are cited as examples of domineering attitudes from command pilots and overconscientiousness on the parts of copilots, who may refuse to relay information forcefully enough or to take control of the aircraft in the case of pilot incapacitation. NASA studies of crew performance in controlled, simulator settings, concentrating on communication, decision making, crew interaction, and integration showed that efficient communication reduced errors. Acknowledgements served to encourage correct communication. The best crew performance is suggested to occur with personnel who are capable of both goal and group orientation. Finally, one bad effect of computer controlled flight is cited to be the tendency of the flight crew to think that someone else is taking care of difficulties in threatening situations.
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The possible hazards presented by orbital debris have been a matter of concern since the early 1960s. The area of initial concern was the potential hazard of the Earth from reentering debris. In the very early days of the space program, it was believed that only specially protected objects would survive reentry. Subsequent events showed this to be incorrect. The recognition of the potential hazard of orbital debris to orbiting objects did not occur until the late 1970s. Concern over this potential hazard has increased, and has also given rise to a number of policy issues. These issues are, at present, largely unresolved.
The objective of this project was to develop a user-friendly interactive computer program to be used as an analytical tool by structural designers. Its intent was to do preliminary, approximate stress analysis to help select or verify sizing choices for composite structural members. The approach to the project was to provide a subroutine which uses classical lamination theory to predict an effective elastic modulus for a laminate of arbitrary material and ply orientation. This effective elastic modulus can then be used in a family of other subroutines which employ the familiar basic structural analysis methods for isotropic materials. This method is simple and convenient to use but only approximate, as is appropriate for a preliminary design tool which will be subsequently verified by more sophisticated analysis. Additional subroutines have been provided to calculate laminate coefficient of thermal expansion and to calculate ply-by-ply strains within a laminate.
An interface between Cosmic/NASTRAN and GIFTS has recently been released, combining the powerful pre- and post-processing capabilities of GIFTS with Cosmic/NASTRAN's analysis capabilities. The interface operates on a wide range of computers, even linking Cosmic/NASTRAN and GIFTS when the two are on different computers. GIFTS offers a wide range of elements for use in model construction, each translated by the interface into the nearest Cosmic/NASTRAN equivalent; and the options of automatic or interactive modelling and loading in GIFTS make pre-processing easy and effective. The interface itself includes the programs GFTCOS, which creates the Cosmic/NASTRAN input deck (and, if desired, control deck) from the GIFTS Unified Data Base, COSGFT, which translates the displacements from the Cosmic/NASTRAN analysis back into GIFTS; and HOSTR, which handles stress computations for a few higher-order elements available in the interface, but not supported by the GIFTS processor STRESS. Finally, the versatile display options in GIFTS post-processing allow the user to examine the analysis results through an especially wide range of capabilities, including such possibilities as creating composite loading cases, plotting in color and animating the analysis.