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Meson factories, pi meson delivery, and pi meson dosimetry for cancer therapy

Description: The meson therapy research program at the Los Alamos Meson Physics Facility (LAMPF) is briefly described. It is stated that tests will start on a magnetic collection channel for pions at LAMPF within one or two months, and the biomedical pion channel is described. The problems encountered in pion dosimetry are briefly discussed. (WDK)
Date: January 1, 1973
Creator: Knapp, E.A.
Partner: UNT Libraries Government Documents Department

Repair of human DNA: radiation chemical damage in normal and xeroderma pigmentosum cells

Description: The photolysis of bromodeoxyuridine (BrdUrd) incorporated during repair was used for the assay of DNA repair in human cells. This assay supplies a characterization of the sequence of repair events that occur in human cells after radiation exposure, both ultraviolet and ionizing, and permits an estimation of the size of the average repaired region after these physical insults to DNA. Chemical insults to DNA are discussed and an attempt is made to liken the repair processes after chemical damages of various kinds to those repair processes that occur in human DNA after damage from physical agents. Results are reported indicating that, under certain conditions, repair events resembling those seen after uv radiation can be observed in normal human cells after ionizing radiation and that xeroderma pigmentosum cells, defective in the repair of uv-induced DNA damage, show defective repair of these uv-like DNA lesions induced by ionizing radiation. (CH)
Date: January 1, 1974
Creator: Regan, J. D. & Setlow, R. B.
Partner: UNT Libraries Government Documents Department

Incentives for partitioning high-level waste

Description: The incentives for separating and eliminating various elements (but particularly the transuranics) from radioactive waste prior to final geologic storage were investigated. Exposure pathways to man were defined, and potential radiation doses to an individual living within the region of influence of the underground storage site were calculated. The accumulated high-level waste (i.e., the fission product waste produced by reprocessing spent fuel) from the U. S. nuclear power economy through the Year 2000 was the assumed radionuclide source, and western U. S. desert subsoil was the assumed geologic medium. The results of the study showed that for reasonable storage conditions the potential incremental radiation doses would be of the same order as, or less than, doses from natural sources. It was therefore concluded that for the situations investigated the incentives for special effort to remove any elements, including the transuranics, from high-level waste are vanishingly small. The study results also showed that incentives exist for converting high-level calcine into glass. (auth)
Date: November 1, 1975
Creator: Burkholder, H.C.; Cloninger, M.O.; Baker, D.A. & Jansen, G.
Partner: UNT Libraries Government Documents Department

Strategic considerations in planning a counterevacuation

Description: The Soviet Union has highly developed plans to evacuate their population centers in a nuclear confrontation. Their plans include construction of expedient shelters in the outlying areas and continued operation of their essential industry by commuting workers. If they should successfully implement their plan, a subsequent nuclear exchange with the United States would cost them far fewer casualties than they suffered in World War II. Without a corresponding evacuation, the US could lose from 50 to 70 percent of its population. This asymmetry in vulnerability, if allowed to persist, would seriously weaken the bargaining position of the US President. To restore the balance, a great reduction in vulnerability can be achieved most economically by planning a US counterevacuation as a response to a Soviet evacuation. Russian historical experience with murderous invaders, most recently in World War II, has made authoritarian defense measures involving civilians and property in peacetime quite acceptable in their culture. In the US, widescale use of private property and civilian participation in defense activity are not feasible until the development of a grave crisis. Hence US evacuation plans must differ in several important respects from the Soviet plans. However, this preliminary study indicates that the US has ample material resources to move and shelter its population at least as effectively as the Soviet Union. Perhaps the most critical disadvantage of the US is in morale, as evidenced by the widespread misconception that effective survival measures are not possible. (auth)
Date: December 1, 1975
Creator: Chester, C.V.; Cristy, G.A. & Haaland, C.M.
Partner: UNT Libraries Government Documents Department

Available space for a totally implantable cardiac prosthesis. Annual progress report, April 1, 1973--March 31, 1974

Description: Methods were developed for generating an integrated, statistical model of the anatomical structures within the human thorax relevant to radioisotope powered artificial heart implantation. These methods involve measurement and analysis of anatomy in four areas: chest wall, pericardium, vascular connections, and great vessels. A model for the prediction of thorax outline from radiograms was finalized. These models were combined with 100 radiograms to arrive at a size distribution representing the adult male and female populations. (CH)
Date: April 1, 1974
Creator: Nose, Y.
Partner: UNT Libraries Government Documents Department

Argonne Radiological Impact Program (ARIP). Part I. Carcinogenic hazard from low-level, low-rate radiation

Description: The entire Argonne Radiological Impact Program is briefly outlined, and part of the program dealing with radiation hazards from nuclear power plants is discussed in detail. Various models and predictions of carcinogenic hazard are examined and compared with actual experience in U. S. and foreign populations. All of the models predict a significant increment in malignant mortality with increasing background. Observation of the actual populations at risk shows not only no increment, but an actual decrement, so that these predictions are left quite without observational support. It is concluded that extrapolation of high- rate and usually hlgh dose-level studies to low rates and low levels is probably invalid, and that radiation at such levels and rates does not constitute an environmental carcinogen of significance. (auth)
Date: September 1, 1973
Creator: Frigerio, N.A.; Eckerman, K.F. & Stowe, R.S.
Partner: UNT Libraries Government Documents Department

Film techniques in radiotherapy for treatment verification, determination of patient exit dose, and detection of localization error

Description: In patient radiation therapy, it is important to know that the diseased area is included in the treatment field and that normal anatomy is properly shielded or excluded. Since 1969, a film technique developed for imaging of the complete patient radiation exposure has been applied for treatment verification and for the detection and evaluation of localization errors that may occur during treatment. The technique basically consists of placing a film under the patient during the entire radiation exposure. This film should have proper sensitivity and contrast in the exit dose exposure range encountered in radiotherapy. In this communication, we describe how various exit doses fit the characteristic curve of the film; examples of films exposed to various exit doses; the technique for using the film to determine the spatial distribution of the absorbed exit dose; and types of errors commonly detected. Results are presented illustrating that, as the frequency of use of this film technique is increased, localization error is reduced significantly. (auth)
Date: January 1, 1974
Creator: Haus, A.G. & Marks, J.E.
Partner: UNT Libraries Government Documents Department