Advances in Radiation Biology, Volume 12, provides an overview of the state of knowledge in the field of radiation biology. Environmental matters are continuing to produce surprises and remain sources of concern. The safe disposal of radioactive waste still is a major problem facing the nuclear power industry. A possible solution is discussed here. New information about the survivors from radiation exposure at Hiroshima and Nagasaki has emphasized the consequences of brain damage in the developing embryo, the importance of late radiation carcinogenesis, and the roles played by age and sex in human radiation responses. It also is prompting an increasing number of scientists involved in radiation protection to question the use of small animal models to quantify late radiation effects in humans. Contributions to this volume deal with experimental and other aspects of those problems.Finally, increasing confirmation of the dose rate response for densely ionizing radiations has highlighted the hazard they pose to humans in the terrestrial and extraterrestrial environments. Therefore, the intention of agencies in the United States and elsewhere to generate better funded and more scientifically perspicacious programs of space radiation biology is welcome. Possible interests of the military in that regard are also considered.

PrefaceDNA Repair in Yeast: Genetic Control and Biological Consequences I. Introduction II. The Excision-Resynthesis Repair Process: The RAD3 Group III. The Recombinational Repair Process: The RAD52 Group IV. The Mutagenic Repair Pathway: The RAD6 Group V. Inducible Repair Functions in Yeast? VI. Conclusion ReferencesExternal Radiation Carcinogenesis I. Introduction II. Dose III. Dose-Response Relationships IV. Dose Rate and Fractionation V. Quality Factors VI. Stochastic Effects and Dose Responses VII. Host Factors VIII. Mechanisms of Radiation Carcinogenesis IX. Combined Effects of Radiation and Other Agents X. Conclusions ReferencesPostimplantation Defects in Development following Ionizing Irradiation I. Introduction and Historical Review II. Normal Sequence of Developmental Stages III. Phenomenology of Developmental Disturbances in Mammals IV. Dose-Response Relations and Modification of Effects V. Mechanisms of Manifestation and Compensation of Effects VI. Radiogenic Developmental Disturbances in Man VII. Extrapolation from Animal Data to Radioprotection in Humans ReferencesCultures of Preimplantation Mouse Embryos: A Model for Radiobiological Studies I. Introduction II. Techniques for the Culture of Preimplantation Mouse Embryos III. Development of Preimplantation Mouse Embryos in Vivo and in Vitro IV. Morphological Development after Irradiation V. Cell Proliferation VI. Cytogenetic Effects VII. DNA Repair in Preimplantation Mouse Embryos VIII. Conclusions ReferencesResearch Issues for Radiation Protection for Man during Prolonged Spaceflight I. Introduction II. Space Radiation Environment III. Response to Irradiation in Space IV. Physiological Adaptation to Space V. Enhancement of Radiation Syndromes VI. Mitigation of Radiation Syndromes VII. Summary ReferencesChemical Protection against Ionizing Radiation I. Introduction II. Factors that Influence Radiosensitivity III. Biochemical Mechanisms of Radioprotector Action IV. Perspectives and Conclusions ReferencesSubseabed Disposal of High-Level Nuclear Wastes I. Introduction II. Radioactivity and Resulting Dose Rates in the Oceans III. U.S. Subseabed Program Radiobiological Research IV. Future Work ReferencesIndex