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Full-Text Articles in Physics
Katz Model Prediction Of Caenorhabditis Elegans Mutagenesis On Sts-42, Francis A. Cucinotta, John W. Wilson, Robert Katz, Gautam Badhwar
Katz Model Prediction Of Caenorhabditis Elegans Mutagenesis On Sts-42, Francis A. Cucinotta, John W. Wilson, Robert Katz, Gautam Badhwar
Robert Katz Publications
The Katz track structure model has been applied to describe recessive lethal mutagenesis in the nematode Caenorhabditis elegans after exposure to heavy ions. Based on models of the cosmic-ray environment and heavy-ion transport, mutation rates for the International Microgravity Laboratory 1 (IML-1) experiment on the Space Transportation System 42 (STS-42) are predicted and the results are discussed.
Track Structure Model Of Cell Damage In Space Flight, Robert Katz, Francis A. Cucinotta, John W. Wilson, Judy L. Shinn, Duc M. Ngo
Track Structure Model Of Cell Damage In Space Flight, Robert Katz, Francis A. Cucinotta, John W. Wilson, Judy L. Shinn, Duc M. Ngo
Robert Katz Publications
Cell damage by high linear energy transfer (LET) radiations has been described by a phenomenological model (track theory) for more than 20 years. With track theory, molecules of biological significance (dry enzymes and viruses) act as one-hit detectors. Recent additions to tire class of one-hit detectors arc Escherichia coil B, and single- and double-strand breaks in SV-40 virus in EO buffer, where indirect effects predominate. The response of cells (survival, transformation, and chromosome aberration) to these radiations is typically described by a four-parameter model whose numerical values are determined from the equations of the theory being fit to experimental …
Track Structure Model For Damage To Mammalian Cell Cultures During Solar Proton Events, Francis A. Cucinotta, J. W. Wilson, L. W. Townsend, J. L. Shinn, Robert Katz
Track Structure Model For Damage To Mammalian Cell Cultures During Solar Proton Events, Francis A. Cucinotta, J. W. Wilson, L. W. Townsend, J. L. Shinn, Robert Katz
Robert Katz Publications
Solar proton events (SPEs) occur infrequently and unpredictably, thus representing a potential hazard to interplanetary space missions. Biological damage from SPEs will be produced principally through secondary electron production in tissue, including important contributions due to delta rays from nuclear reaction products. We review methods for estimating the biological effectiveness of SPEs using a high energy proton model and the parametric cellular track model. Results of the model are presented for several of the historically largest flares using typical levels and body shielding.
Comment On Ncrp Report No. 104, "The Relative Biological Effectiveness Of Radiations Of Different Quality", Robert Katz
Comment On Ncrp Report No. 104, "The Relative Biological Effectiveness Of Radiations Of Different Quality", Robert Katz
Robert Katz Publications
The validity of a linear extrapolation to lowest fluences of charged particles demands that the transit of a single charged particle through the target volume is capable of inducing the chain of events leading to an observable end-point. This is always the case for one-hit detectors. It is not always the case for biological cells and tissues (Katz and Hofmann 1982).
By way of example, Cole ct al. (1980) found that, on average, some 500 electrons pass into the nucleus of a CHO cell for inactivation. Similarly, Warters et al. (1977) found that some 500 tritium decays in the nucleus …