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Reply To D. E. Watt, A. S. Alkharam, M. B. Child And M. S. Salikin, “Dose As A Damage Specifier In Radiobiology For Radiation Protection." A Comment On "Dose" (Radiat. Res. 137, 410-413, 1994), Robert Katz
Robert Katz Publications
The authors are generous in observing that "the high degree of success achieved by (Katz's δ-ray theory of track structure) in fits to survival curves for heavy ions, and in analysis and prediction of other biological effects is almost legend." We remind them that the model is physical, and has little to do with biology in an explicit way, except that an oversimplified "bean bag" model of a eukaryotic cell is used, in which the bag represents the cell nucleus and the beans represent internal targets. No explicit biologically mechanistic structure or response is inferred. No reference is made to …
On The Linear Extrapolation To Low Doses, Robert Katz, Michael P. R. Waligórski
On The Linear Extrapolation To Low Doses, Robert Katz, Michael P. R. Waligórski
Robert Katz Publications
While radiobiological data are conveniently fitted by a linear quadratic formula to data of limited dynamic range at doses typically exceeding 1 Gy, they are extrapolated linearly to doses below a milligray for the evaluation of low dose RBEs. However a single relativistic electron passing through a cell nucleus deposits a “dose” there in the neighborhood of a milligray. The validity of the linear extrapolation then rests on the demonstration that a single electron transit through a cell nucleus can cause inactivation or mutation or can lead to cancer induction. The extrapolation made is a huge one, of some three …
Dose, Robert Katz
Dose, Robert Katz
Robert Katz Publications
The universal use of dose as a normalizing parameter in radiobiology is based entirely on the availability of measuring instruments. It is a poor basis for predicting or understanding the relationship between an irradiation and the resulting end point. Energy deposited is not the cause of an interaction. It is a secondary effect. The interaction is best described by fluence and cross section. Energy deposited depends principally upon inelastic collision cross sections for the interaction of electrons with molecules. Especially for heavy-ion bombardments, for high-LET radiations, inelastic electron collision cross sections relate only remotely to the observed end points of …
Radiosensitivity Parameters For Lethal Mutagenesis In Caenorhabditis Elegans, F. A. Cucinotta, J. W. Wilson, Robert Katz
Radiosensitivity Parameters For Lethal Mutagenesis In Caenorhabditis Elegans, F. A. Cucinotta, J. W. Wilson, Robert Katz
Robert Katz Publications
For the first time track structure theory has been applied to radiobiological effects in a living organism. Data for lethal mutagenesis in Caenorhabditis elegans, obtained after irradiation with nine different types of ions of atomic number 1-57 and gamma rays have yielded radiosensitivity parameters (E0, σ0, K, m = 68 Gy, 2.5 x 10-9 cm2, 750, 2) comparable with those found for the transformation of C3HT10 1/2 cells (180 Gy, 1.15 x 10-10 cm2, 750, 2) but remote from those (E0 and σ0 = ≈2 Gy, ≈5 …
Survey Of Cellular Radiosensitivity Parameters, Robert Katz, Rashidah Zachariah, Francis A. Cucinotta, Chunxiang Zhang
Survey Of Cellular Radiosensitivity Parameters, Robert Katz, Rashidah Zachariah, Francis A. Cucinotta, Chunxiang Zhang
Robert Katz Publications
A model of the formation of particle tracks in emulsion has been extended through the use of biological target theory to formulate a theory of the response of biological cells and molecules of biological importance to irradiation with energetic heavy ions. For this purpose the response to γ rays is represented by the single-hit, multi-target model with parameters m and D0, while additional parameters κ (or a0) and σ0 are required to represent the size of internal cellular targets and the effective cross-sectional area of the cell nucleus, respectively, for heavy-ion bombardments. For one-or-more-hit detectors, …