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Sulzman, Frank M.

Publications and source records attributed to Sulzman, Frank M..

NASA Strategy to Safely Live and Work in the Space Radiation Environment

In space, astronauts are constantly bombarded with energetic particles. The goal of the National Aeronautics and Space Agency and the NASA Space Radiation Project is to ensure that astronauts can safely live and work in the space radiation environment. The space radiation environment poses both acute and chronic risks to crew health and safety, but unlike some other aspects of space travel, space radiation exposure has clinically relevant implications for the lifetime of the crew. Among the identified radiation risks are cancer, acute and late CNS damage, chronic and degenerative tissue decease, and acute radiation syndrome. The term "safely" means that risks are sufficiently understood such that acceptable limits on mission, post-mission and multi-mission consequences can be defined. The NASA Space Radiation Project strategy has several elements. The first element is to use a peer-reviewed research program to increase our mechanistic knowledge and genetic capabilities to develop tools for individual risk projection, thereby reducing our dependency on epidemiological data and population-based risk assessment. The second element is to use the NASA Space Radiation Laboratory to provide a ground-based facility to study the health effects/mechanisms of damage from space radiation exposure and the development and validation of biological models of risk, as well as methods for extrapolation to human risk. The third element is a risk modeling effort that integrates the results from research efforts into models of human risk to reduce uncertainties in predicting the identified radiation risks. To understand the biological basis for risk, we must also understand the physical aspects of the crew environment. Thus, the fourth element develops computer algorithms to predict radiation transport properties, evaluate integrated shielding technologies and provide design optimization recommendations for the design of human space systems. Understanding the risks and determining methods to mitigate the risks are keys to a successful radiation protection strategy.

Cucinotta, Francis A.

A Strategy to Safely Live and Work in the Space Radiation Environment

The goal of the National Aeronautics and Space Agency and the Space Radiation Project is to ensure that astronauts can safely live and work in the space radiation environment. The space radiation environment poses both acute and chronic risks to crew health and safety, but unlike some other aspects of space travel, space radiation exposure has clinically relevant implications for the lifetime of the crew. The term safely means that risks are sufficiently understood such that acceptable limits on mission, post-mission and multi-mission consequences (for example, excess lifetime fatal cancer risk) can be defined. The Space Radiation Project strategy has several elements. The first element is to use a peer-reviewed research program to increase our mechanistic knowledge and genetic capabilities to develop tools for individual risk projection, thereby reducing our dependency on epidemiological data and population-based risk assessment. The second element is to use the NASA Space Radiation Laboratory to provide a ground-based facility to study the understanding of health effects/mechanisms of damage from space radiation exposure and the development and validation of biological models of risk, as well as methods for extrapolation to human risk. The third element is a risk modeling effort that integrates the results from research efforts into models of human risk to reduce uncertainties in predicting risk of carcinogenesis, central nervous system damage, degenerative tissue disease, and acute radiation effects. To understand the biological basis for risk, we must also understand the physical aspects of the crew environment. Thus the fourth element develops computer codes to predict radiation transport properties, evaluate integrated shielding technologies and provide design optimization recommendations for the design of human space systems. Understanding the risks and determining methods to mitigate the risks are keys to a successful radiation protection strategy.

Corbin, Barbara J.

Neurosciences research in space - Future directions

In order to gain a better understanding of the effects of long-duration space missions on the central nervous system, near-term research, to take place from 1990-1995, will be directed at investigating the acute effects of microgravity and the 'space adaptation syndrome'. These include experiments scheduled for the Spacelab Life Sciences 1 which is designed to evaluate changes in the visual, vestibular, and proprioceptive systems. An extensive series of experiments, collectively termed Microgravity Vestibular Investigations (MVI), is also planned for the IML-1 mission to be flown in 1992. The IML-2 mission will emphasize behavior and performance, biological rhythms, and further vestibular studies. Mid-term goals, projected to be achieved from 1995-2000, include the use of new technology such as magnetic recording techniques. Long-term goals are also discussed including studies dealing with neuronal plasticity and sensory substitution, augmentation, and robotic telepresence.

Sulzman, Frank M.

NASA plans and opportunities

The NASA plans for the Life Science program of a series of space flight activities throughout the decade of the 1990s are discussed with particular attention given to the NASA life science goals and objectives and to the particular space missions which will carry out these objectives. These space missions and specially designed facilities for experiments in space include Space Station Freedom, Space Biology Initiative, Gravitational Biology Facility, Life Sciences Centrifuge Facility, Controlled Ecological Life Support Systems Test Facility, and Exobiology Facility.

Sulzman, Frank M.

Life sciences and Mars exploration

The major life science considerations for Mars exploration missions are discussed. Radiation protection and countermeasures for zero gravity are discussed. Considerations of crew psychological health considerations and life support systems are addressed. Scientific opportunities presented by manned Mars missions are examined.

Sulzman, Frank M.

Physiological adaptation to space flight

In space, adaptive physiological changes have been observed in virtually all body systems, but how far these changes progress with time is not known. Their time course demonstrates variable patterns; some systems show evidence of gradual and progressive change. Biomedical postflight data have shown that a compensatory period of readaptation to one gravity is required after space flight, with longer intervals required for longer missions. Consistent readaptation trends include orthostatic intolerance and neurovestibular difficulties. For the long-duration missions of the exploration era, it is critical to determine the extent to which deleterious changes (e.g., bone loss and possible immunological changes) can be reversed upon return to earth. Radiation protection is another critical enabling element for missions beyond low earth orbit. Radiation exposure guidelines have not been established for exploration missions. Currently our experience is insufficient to prescribe countermeasures for the stay times associated with a lunar base or a mission to Mars. Artificial gravity may provide a solution, but the level and duration of exposure necessary to prevent deconditioning must be determined. Central issues for medical care in remote settings are preventive, diagnostic, and therapeutic care and the minimization of risk.

Nicogossian, Arnauld E.

Enabling human exploration of space - A life sciences overview

In the transition from the short-duration missions of the Space Shuttle era to long-duration exploration missions, the health and safety of crewmembers must be ensured. The body undergoes many complex physiological changes as a result of its adaptation to a microgravity environment and U.S. and Soviet experiences have shown that time is required for readaptation to gravity. The consequences of these changes for the extended exploration missions envisioned for the future are unknown. A Mars mission may require crewmembers to spend many months in microgravity, and then work effectively in a one-third gravity environment. Other problems may arise when returning crewmembers must readapt to earth's gravity. Life Sciences activities are being planned to systematically address the physiological issues involved with long-term manned exploration missions, through ground-based studies and flight investigations on the Shuttle and Space Station Freedom. The areas of focus are artificial gravity, radiation, health care, and space human factors.

Gaiser, Karen K.

Making a home in space

NASA's Office of Aeronautics and Space Technology has undertaken a series of manned space presence-development efforts under the aegis of the Civil Space Technology Initiative (CSTI) and Project Pathfinder. Typical of these CSTI efforts is the Aeroassist Flight Experiment, which will demonstrate techniques suitable in aerobrake design for slow trajectories to Mars and for lunar mission return. Long-duration human operations in space are a major element of Pathfinder, giving attention to such problems as space radiation exposure effects that could be several orders of magnitude greater on interplanetary exploration missions than on typical Space Shuttle flights. Mars Observer and Lunar Observer orbital missions are planned as a steppingstone to manned planetary exploration.

Aaron, John

The biological clock of Neurospora in a microgravity environment

The effects of simulated microgravity (via the use of a slowly rotating clinostat), altered orientation (via alterations in the vector of a 1-g force), and hypergravity (via centrifugation) on the circadian rhythm of conidiation in Neurospora crassa were investigated. It was found that the clinostat, while capable of producing some of the microgravity effects seen in space (Sulzman, 1984), did not produce major repeatable results. Similarly, alterations of the vector of a 1-g gravity load were not adequate simulations of space flight on the conidiation rhythm. The results on the acute and chronic exposures to hypergravity demonstrated that chronic exposure of Neurospora to a 3-g force had no damping effect. On the other hand, an acute 10-min exposure to this hypergravity (the lift-off conditions) was found to cause significant damping on the circadian rhythm of conidiation. This effect was eliminated by a brief light pulse given 36 hrs after the exposure to 3 g.

Ferraro, James S.

Gravitational biology and the mammalian circadian timing system

Using published reports, this paper compares and contrasts results on the effects of altered gravitational fields on the regulation in mammals of several physiological and behavioral variables with the circadian regulation of the same variables. The variables considered include the temperature regulation, heart rate, activity, food intake, and calcium balance. It is shown that, in rats, the homeostatic regulation of the body temperature, heart rate, and activity becomes depressed following exposure to a 2 G hyperdynamic field, and recovers within 6 days of 1 G condition. In addition, the circadian rhythms of these variables exhibit a depression of the rhythm amplitude; a recovery of this condition requires a minimum of 7 days.

Fuller, Charles A.

Life sciences - On the critical path for missions of exploration

Life sciences are important and critical to the safety and success of manned and long-duration space missions. The life science issues covered include gravitational physiology, space radiation, medical care delivery, environmental maintenance, bioregenerative systems, crew and human factors within and outside the spacecraft. The history of the role of life sciences in the space program is traced from the Apollo era, through the Skylab era to the Space Shuttle era. The life science issues of the space station program and manned missions to the moon and Mars are covered.

Sulzman, Frank M.

Artificial gravity - The evolution of variable gravity research

The development of a space life science research program based on the use of rotational facilities is described. In-flight and ground centrifuges can be used as artificial gravity environments to study the following: nongravitational biological factors; the effects of 0, 1, and hyper G on man; counter measures for deconditioning astronauts in weightlessness; and the development of suitable artificial gravity for long-term residence in space. The use of inertial fields as a substitute for gravity, and the relations between the radius of the centrifuge and rotation rate and specimen height and rotation radius are examined. An example of a centrifuge study involving squirrel monkeys is presented.

Fuller, Charles A.