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The genomic viral RNA (vRNA) segments of influenza A virus contain specific packaging signals at their termini that overlap the coding regions. To further characterize cis-acting signals...Full Text Available

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Endoreduplication represents a cell cycle variant during which multiple rounds of DNA replication occur without subsequent chromosome separation and cytokinesis, resulting into a cellular increase of the DNA content. Although the DNA ploidy level of cells is controlled by external stimuli such as light, currently limited knowledge is available on how environmental signals regulate the endoreduplication cycle at the molecular level. Previously, we have demonstrated that the conversion from the mitotic cell cycle into an endoreduplication cycle is mediated by the atypical E2F transcription factor DEL1 that operates as a repressor of endocycle onset. Here, we identified DEL1 as a transcriptional target of the classical E2Fb and E2Fc transcription factors that antagonistically control DEL1 transcript levels through competition for a single E2F cis-acting binding site. Correspondingly with the reported opposite effect of light on the E2Fb and E2Fc protein levels, the ...

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We report a search for small RNAs (sRNAs) in the low-GC, gram-positive human pathogen Streptococcus pneumoniae. Based on bioinformatic analyses by Livny et al. (J. Livny, A. Brencic, S. Lory, and M. K. Waldor, Nucleic Acids Res. 34:3484-3493, 2006), we tested 40 candidates by Northern blotting and confirmed the expression of nine new and one previously reported (CcnA) sRNAs in strain D39. CcnA is one of five redundant sRNAs reported by Halfmann et al. (A. Halfmann, M. Kovacs, R. Hakenbeck, and R. Bruckner, Mol. Microbiol. 66:110-126, 2007) that are positively controlled by the CiaR response regulator. We characterized 3 of these 14 sRNAs: Spd-sr17 (144 nucleotides [nt]; decreased in stationary phase), Spd-sr37 (80 nt; strongly expressed in all growth phases), and CcnA (93 nt; induced by competence stimulatory peptide). Spd-sr17 and CcnA likely fold into structures containing single-stranded regions between hairpin structures, whereas Spd-sr37 forms a base-paired ...

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... Solar Cell Radiation Respinnse Near the Interface o~f fliffprerv- ... 5 4. CALCUTl-ATED SOLAR CELL RLSPONSE FOR VARIOUS BASE MATERIALS ...

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Although skin is usually exposed during human exposures to ionizing radiation, there have been no thorough examinations of the transcriptional response of skin fibroblasts and keratinocytes...Full Text Available

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UK PubMed Central (United Kingdom)

To capitalize on the response of tumor cells to ionizing radiation, we developed a controlled-release nanoparticle drug delivery system using a targeting peptide that recognizes a radiation-induced...Full Text Available

UK PubMed Central (United Kingdom)

Inhibition of photosynthesis by ultraviolet-A radiation (UV-A, 315-380 nanometers) was examined in three marine angiosperms: Halophila engelmannii Aschers, Halodule wrightii...Full Text Available

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Accidents Accident Preparedness, Accident Prevention, Chemical Accidents, Radiation Accidents Characterization Contingency Plans National Contingency Plan (NCP), Oil Removal...

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A multi-spectral Schottky barrier infrared detector array in which individual pixels of radiation from a remote radiating object are detected by two or more Schottky barrier infrared radiation detectors each having a different spectral response so as to provide a ''color'' discrimination for the array.

International Nuclear Information System (INIS)

This manual was written for individuals who wish to become qualified in radiation protection as an adjunct to working with sources of ionizing radiation or using radionuclides in the field of medicine. It provides the radiation user with information needed to protect himself and others and to understand and comply with governmental and institutional regulations regarding the use of radionuclides and radiation machines. It is designed for a wide spectrum of users, including physicians, research scientists, engineers, and technicians. It should be useful also to radiation safety officers, members of radiation safety committees, and others who are responsible for the proper use of radiation sources, although they may not be working with the sources directly. The presentation in this manual is designed to obviate the need ...

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Ramsar, a city in the northern Iran, has the highest level of natural background radiation in the world. It has been clearly shown that low doses of ionising radiation can induce resistance to subsequent higher exposures. This phenomenon is termed radioadaptive response. We have compared induction of cytogenetic radioadaptive response by High Natural Background Radiation (HNBR) in Ramsar and X-ray occupational exposure as conditioning doses in human peripheral blood lymphocytes. 30 healthy control individuals, living in Ramsar but in normal background radiation areas, 15 healthy individuals from Talesh Mahalleh, a region with extraordinary high level of background radiation, and 7 X-ray radiographers working in Ramsar hospital located in normal natural background ionising radiation area were evaluated. Peripheral blood ...

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The document, based on European guidelines, was jointly developed by radiation oncologists, radiation physicists and radiation technologists. It contains the aims of the guidelines, professional profiles, roles and responsibilities, personnel and equipment requirements, procedures.

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The great uranium debate throughout the industrialised world has intensified awareness of the biological hazards from ionizing radiation. It is therefore appropriate to use this awareness to draw attention to medical X-Radiation which today represents the most significant risk to future generations. There is ample legislation to control proliferation of nuclear development but in diagnostic radiology proliferation is unlimited; most international surveys indicate an unchecked annual growth rate of 15%. The article looks at risk hypotheses, dose measurements and the responsibilities of practising radiographers, and also reviews the international situation as reported at the 1977 world congress of radiation protection.

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Based on the practical condition of the plant and in reference to advanced management experiences worldwide, Daya Bay Nuclear Power Plant has established its own peculiar management system for radiation protection management and ALARA implementation. The characteristics of the system are: radiation protection training to all workers, active involvement of all managers and staffs, and whole process safety control to maintenance activities. The management philosophy of 'workers are responsible for their own radiation safety' is adopted in the plant. A strict, formalized and systematic whole staff radiation protection training, evaluation, authorization and periodically refreshing mechanism had been established and executed in the plant. In the organizational point of view, the responsibilities of line managers were specified in plant procedures, ALARA coordination ...

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Endothelial dysfunction is involved in radiation responses in many normal tissues, including intestine. Endothelium-directed interventions ameliorate intestinal radiation injury (radiation enteropathy) in animal models, and anecdotal reports also suggest a beneficial effect of heparin. This study assessed low molecular weight heparin as an intestinal radiation response modifier. Rats underwent localized small bowel irradiation. Groups of rats were treated with saline, nadroparin (3 mg/kg/d), or a non-anticoagulant heparin (SR80258, 3 mg/kg/d), from 3 days before to 2 weeks after irradiation. The intestinal radiation response was assessed 2 weeks and 6 weeks after irradiation using quantitative histology; morphometry, and cellular and molecular end-points. Compared to vehicle-treated controls, nadroparin significantly ...

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Plantago ovata Forsk - an economically important medicinal plant - was analyzed for trace elements and chlorophyll in a study of the effects of gamma radiation on physiological responses of the seedlings. Proton-induced X-ray emission (PIXE) technique was used to quantify trace elements in unirradiated and gamma-irradiated plants at the seedling stage. The experiments revealed radiation-induced changes in the trace element and chlorophyll concentrations.

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Tow experiments were carried out in 1981 and 1982 growth seasons at the greenhouse of the department of agriculture for soils and water researches, atomic energy authority, at inshas, to investigate the responses of two mutation derived lines of sesame and the local cultivar giza 25 to the application of micro nutrients. The possible effect of radiation on germination and growth of sesame seed was also studied in a separate experiment conducted in 1985 season, at inshas.

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This chapter is an overview of total-ionizing-dose and single-event hardening techniques and should be used as a guide to a range of research publications. It should be stressed that there is no clear and simple route to a radiation-tolerant silicon integrated circuit. What works for one fabrication process may not work for another, and there are many complex interactions within individual processes and designs. The authors have attempted to highlight the most important factors and those process changes which should bring improved hardness. The main point is that radiation-hardening as a procedure must be approached in a methodical fashion and with a good understanding of the response mechanisms involved.

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The rate was studied of radiation destruction of phenol aqueous solutions at a concentration range of 1 to 100 ppm. Irradiated were model solutions containing additions of some organic and inorganic substances typical of the petrochemical industry. In view of the fact that the radiation destruction kinetics is determined by the amount of dissolved oxygen in the sample and by the phenol concentration, relatively low doses were used. Thus, a sufficient amount of oxygen in the sample and therefore the oxidation mechanism of radiolysis were ensured. The dose-response relationships for phenol destruction were studied using doses of 50, 100, 200 and 400 J.kg"-"1; the limit dose was 500 J.kg"-"1. From the results obtained, a kinetic model was constructed of radiation phenol oxidation in aqueous solutions in the presence of various organic and inorganic additions. (B.S.).

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In May 1990 a group of scientists representing several federal agencies, the International Society of Regulatory Toxicology and Pharmacology, the private sector, and academia met to develop a strategy to encourage the study of the biological effects of low level exposures (BELLE) to chemical agents and radioactivity. A workshop was held in 1991 with seven invited speakers focusing on the toxicological implications of biological adaptations. The selection of topics and speakers was designed to consider critically the concept of hormesis, not only in a broad, conceptual manner, but also at the molecular and biochemical levels. These presentations offered a complementary perspective on the diverse range of molecular mechanisms that can become activated at low levels of toxicant exposure. In addition to chemical toxicology research, an overview of current research on 'Effects of low-dose radiation on the immune response' was presented as well as ...

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Purpose: To evaluate the effect of low-dose radiation therapy and surgery on local control in patients with Ewing's Sarcoma. Materials and Methods: Between 1979 and 1995 24 patients (ages 4-47) with Ewing's sarcoma were treated with combined modality therapy that included multi agent chemotherapy, surgical resection, and radiation therapy. Twelve patients had metastatic disease at the time of presentation (pleura = 3, lung = 5, bone 4). Tumor location was central in 16 and peripheral in 8. Multi agent chemotherapy consisted of vincristine/actinomycin D/cyclophosphamide/doxorubicin in 19. The same agents with the addition of ifosfamide and etoposide were given in 5. The extent of resection was considered to be radical in 14 and of the 16 patients who received preoperative chemotherapy, 5 were found to have a pathologic complete response. All patients with lung metastases at diagnosis received whole-lung irradiation to 1400 ...

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The biological effects of ionizing radiation exposure are the result of a complex sequence of physical, chemical, biochemical, and physiological interactions. One way to begin a search for an understanding of health effects of radiation is through the development of phenomenological models of the response. Many models have been presented and tested in the slowly evolving process of characterizing cellular response. A range of models covering different endpoints and phenomena has developed in parallel. Many of these models employ similar assumptions about some underlying processes while differing about the nature of others. An attempt is made to organize many of the models into groups with similar features and to compare the consequences of those features with the actual experimental observations. It is assumed that by showing that some assumptions are inconsistent with experimental observations, the job ...

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ABSTRACT-Here we identify release of annexin A2 into the culture medium in response to low dose X-ray radiation exposure and establish functional linkages to an established paracrine factor-mediated anchorage-independent growth response. Using a standard bicameral coculture model, we observe that annexin A2 levels associated with non-irradiated neighboring cells seeded in the lower chamber (annexin A2 silenced [shRNA] JB6 cells) are increased upon coculture with irradiated (10-50 cGy) JB6 cells seeded in the upper chamber, relative to coculture with sham exposed JB6 cells seeded in the upper chamber, suggesting that annexin A2 released into the medium is capable of communicating in a paracrine fashion. Using a previously established coculture model, we observed that the paracrine factor-mediated anchorage-independent growth response to low dose X-ray radiation is markedly reduced ...

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We have developed a new type personal dosemeter by using a B-10 doped silicon p-n junction detector with a polyethylene radiator and a polyethylene moderator. The purpose of this study was to develop a real time neutron dosemeter with a nearly flat response in the energy range from thermal to 15 MeV and low angular dependence to the incident neutron direction. The neutron response of the dosemeter was obtained with the Monte Carlo calculation and the monoenergetic neutron experiment in a free air field and also under a condition attached on a phantom.

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The objective of this research was to determine improved thermal, epithermal, and fast fluxes and several responses at mechanical test surveillance location keys 2, 4, 5, and 7 of the pressure vessel of the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR) for the beginning of the fuel cycle. The purpose of the research was to provide essential flux data in support of radiation embrittlement studies of the pressure vessel shell and beam tubes at some of the important locations.

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The aim of this work is to determine and compare the dosimetric properties of NaCl and KCl samples using infrared-stimulated luminescence (IRSL) technique. For a material to be used as dosimeter, both the IRSL temperature dependence and the radiation dose response have critical importance. In this work the IRSL characteristics from NaCl and KCl samples were experimentally investigated as a function of temperature and laboratory radiation doses. Dosimetric properties of NaCl and KCl samples were found significantly different. The IRSL signals displayed by NaCl were found to be more stable, reliable and agreeable than those of KCl.

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The condition for obtaining a calorimetric response linear with energy for hadronic showers and an energy resolution that improves as the incident energy increases is the equalization of the electromagnetic (e) and the hadronic (#pi#) signal responses. This equalization is obtained by exploiting a local hardening effect realized through the insertion of low-Z thin plates between the high-Z absorbers and the active material in a hadronic calorimeter with silicon readout. This effect, which allows the reduction of the calorimeter response to the electromagnetic component of the incoming hadronic showers, has been investigated for different low-Z materials. The relevance of some aspects of this study to the radiation hardness of the calorimeters is also addressed. (orig.).

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Nickel ion radiation at 500 C was shown to have a strong effect on the surface electrochemistry and intergranular corrosion (IGC) of stainless steel (SS). Measured current densities in a 1 N sulfuric acid solution at room temperature were increased at active-passive, passive, and transpassive potentials. Radiation effects on the current decay behavior and susecptibility to IGC were similar for a fine-grained (FG) S alloy and for a very large-grained (LG) SS. Radiation-induced segregation (RIS) at the surface was believed to promote higher currents at short times, whereas segregation at grain boundaries was responsible for IG attack. Analytical electron microscopy (AEM) measurements revealed chromium and iron depletion plus Ni and silicon enrichment at grain boundaries in irradiated specimens. Si enhanced dissolution at transpassive potentials, whereas Cr depletion did the same at active-passive and ...

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The assessment and control of fetal exposure to radiation in the workplace is an issue that is complicated by both biological and political/social ramifications. As a result of the dramatic increase in the number of women employed as radiation workers during the past 10 years, many facilities using radioactive materials have instituted fetal protection programs with special requirements for female radiation workers. It is necessary, however, to ensure that any fetal protection program be developed in such a way as to be nondiscriminatory. A study has been initiated whose purpose is to balance the political/social and the biological ramifications associated with occupational protection of the developing embryo/fetus. Several considerations are involved in properly balancing these factors. These considerations include appropriate methods of declaring the pregnancy, training workers, controlling the dose to the embryo/fetus, ...

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A custom-built graphite-coated transmission ionization chamber is compared to the VacuDAP 2001 (VacuTec, Dresden, Germany), which has transparent conductive electrodes. A study was made of the dependence of response on x-ray tube potential for both types of chamber under identical conditions of exposure using over-table and under-table x-ray tubes. Since the calibration factor is the dose-area product of the radiation incident on the patient per chamber reading, it depends on the intrinsic response of the chamber as well as the effect of material in the beam between the x-ray tube and patient. Differences of about 20% were measured between the intrinsic and the over-table calibration factors and between the over-table and the under-table calibration factors for both chambers. The VacuDAP display is specifically calibrated for the over-table condition and would overstate the actual DAP in the under-table case. The intrinsic ...

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Estimations on the somatic and genetic effects of small doses of ionizing radiations in Man have been proposed by the Advisory Committee on the Biological Effects of Ionizing Radiation, set up by the U.S. National Academy of Sciences. They have been published in an important report, issued in 1972, from which we briefly analyze here the Chapter dealing with the somatic effects. Small doses of raditions are expected to promote only carcinogenic effects. After a rapid survey of the human experience on which the estimations are based, as regards the latent period of cancers, the plateau region (period of high risk) and the absolute and relative risk expressed per rem, per 10"6 persons, per year, for leukaemia (having the highest risk) and for the ''other cancers''. These estimations were obtained by linear extrapolation to the 1 rem level from observations made after irradiation at relatively high dose levels and much higher dose-rates. This ...

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This study evaluates the effect of gamma radiation on the viability of fungi and actinomycetes that contaminate medicinal plants. The relationship between the total lipids of some fungi and actinomycetes and their sensitivity to gamma radiation is also investigated. The data reveal that the viable counts of these florae decrease approximately exponentially with the radiation dose, the effective dose for the elimination of these microorganisms being about 5 kGy for all the medicinal plants under study. Response of pure cultures of fungi and actinomycetes isolated from medicinal plants to increasing absorbed doses of gamma radiation indicate that an increase in radioresistance is in the following order: Streptomyces rimosus, Fusarium solani, Nocardia kuroishii. F. oxysporum, A. fumigatus, A. flavus, A. parasiticus and A. ochraceus. The total lipid contents of molds and actinomycetes ...

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The results of Sandia National Laboratories' participation in the NASA Planetary Definition and Design Program are summarized. Areas reported include the characterization of large area cadmium zinc telluride spectrometers and the application of simulation techniques to the prediction of device performance. Also investigated was the response of mercuric iodide devices in the region from 1 to 100 KeV. A literature study to determine the status or radiation damage measurements in room temperature semiconductor devices is also reported.

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Mitotic delay is described as a classical response to radiation; however, circadian rhythmicity in cell division in vivo has not been considered by many authors. The present study investigated the relation between fluctuations reported as mitotic delay and recovery in vivo and circadian oscillations in mitotic index in mouse corneal epithelium. One aspect involved single doses (approximately 600 rad) given to mice at different circadian stages. The normal circadian rhythm in cell division was never obliterated. Inhibition of mitosis was evident but unpredictable, ranging from 6 to 15 hr after irradiation. Recovery was evident only during the daily increase in mitotic index of controls. The classical interpretation of recovery from mitotic delay may be in an in vitro phenomenon not reflecting in vivo responses, which are apparently strongly circadian stage dependent. The second portion of the study demonstrated a ...

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The most important factor in assessing radiologic risk is ensuring scientific means for evaluation of the radioactive release impact upon humans and organisms. To evaluate quantitatively this impact not only knowledge of radioactivity distribution in these dynamical systems is necessary but also understanding the transfer mechanisms between ecosystem components is needed. Thus a complete radioecologic study appear to be very complex and needs defining the source term, dynamic description of radionuclides behavior in the ecosystem, estimation of radiation doses in the major components of the ecosystem and finally the effects of radiation doses upon different parts of the systems. A diagram of the steps implied in evaluation of the effects due to radioactive effluent release in the environment is presented and discussed. The following steps are described: - identification of radioactive sources, as well as their input rate. Presence of noxious ...

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Conditions for radiation induced grafting with butyl acrylate dispersed in water emulsion onto chrome-tanned pig skins have been worked out for #gamma#-rays and electron beam irradiations. The highest yield of grafting was observed at monomer concentration approximately 25% (w/w), dose equal to 25 kGy and dose rate not exceeding 10 MGy/h. At these conditions the yield of grafting attained a value approximately 25% and content of homopolymer in the leather amounted to 6%. The efficiency of monomer to polymer conversion decreases when the concentration of monomer in emulsion and dose rate increases. Yield of homopolymer is independent of the dose rate. An explanation of the observed relations has been proposed. The physical and used properties of grafted leathers were tested. Radiation processed leathers were found superior to samples finished by traditional methods. One has to point to better tolerance against chemical cleaning and reduced water ...

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Measuring gene expression using microarrays is relevant to many areas of biology and medicine, such as follow up of developmental stages and diseases onset, and treatment study. Since there can be tens of thousands of distinct probes on an array, each micro array experiment can accomplish the equivalent number of genetic tests in parallel. Arrays have therefore dramatically accelerated many types of investigations. For example, microarrays can be used to identify stress response genes by comparing gene expression in challenged versus normal cells. In the Molecular and Cellular Biology lab (MCB), the micro array experiments are performed within the Genomic Platform, fully equipped to analyse either the behaviour of bacteria during long space flight, the effect of low dose ionising radiation on the developing organism in mice, or the human individual radiation sensitivity. For the low dose effect, two main stages of ...

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In response to a heat shock, the yeast Saccharomyces cerevisiae undergoes a large increase in its resistance to heat and, by the induction of its recombinational DNA repair capacity, a corresponding increase in resistance to radiation. Yeast which lack mitochondrial DNA, mitochondria-controlled protein synthetic apparatus, aerobic respiration, and electron transport (rho/sup 0/ strain) were used to assess the role of O/sub 2/, mitochondria, and oxidative processes controlled by mitochondria in the induction of these resistances. We have found that rho/sup 0/ yeast grown and heat shocked in either the presence or absence of O/sub 2/ are capable of developing both radiation and heat resistance. We conclude that neither the stress signal nor its cellular consequences of induced heat and radiation resistance are directly dependent on O/sub 2/, mitochondrial DNA, or mitochondria-controlled protein synthetic ...

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Metallic nanoparticles was synthesized in SiO{sub 2} matrices by means of a process of two stages. The first one proceeded via sol-gel, incorporating the metallic precursors to the reaction system before the solidification of the matrix. Later on, the samples underwent a thermal treatment in atmosphere of H{sub 2}, carrying out the reduction of the metals that finally formed to the nanoparticles. Then it was detected the presence of smaller nanoparticles than 20 nm, dispersed and with the property of being liberated easily of the matrix, conserving a free surface, chemically reactive and with response to external electromagnetic radiation. The system SiO{sub 2}-Pd showed an important thermoluminescent response. (Author)

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A comparison is made of the response of a count ratemeter and a pulse counter using the mathematical tool of the Z transform. Transform Z is used for the solution of the convolution integral interpreting the analog output of the count ratemeter used for recording characteristic radiation, excited in the moving beam. The comparison of count rates obtained by the count ratemeter during continuous analysis and the pulse counter during discontinuous measurement gave the transfer function of the count ratemeter in the actual range of count rate. Also discussed is the use of the transfer function for localizing concentration changes in the sample. The use of the described method is demonstrated on the determination of the tin content in tungsten using continuous radionuclide X-ray fluorescence analysis. (B.S.).

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Physicians are exercising their responsibility as healers in their efforts to prevent nuclear war. Death for Hiroshima survivors was experienced in four stages: the immediate impact of destruction, the acute impact of radiation, delayed radiation effects, and later identification as an atomic bomb survivor. Each phase had its physical and psychological impacts and negates Hiroshima as a model for rational behavior despite those who claim survival is possible for those who are prepared. The psychic effects of modern nuclear, chemical, and germ warfare need to be challenged with a symbolization of life and immortality. Studies of psychological reactions to the terror children felt during practice air-raid drills indicate that the fears can be surpressed and re-emerge in adult life as a linking of death with collective annihilation. Other themes which emerge are feelings of impermanence, craziness, identification with the ...

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Data from Monte Carlo transport codes are used to model radiobiological effects. We previously reported the Fourier analysis of ionization data generated by simulating a 500-keV proton traversing water. Here, we extend Fourier analysis to energy transfer data of another radiation type, a 14-MeV #alpha#-particle. A radiobiological model based on this frequency-domain analysis views cell as an information processing system . It lends itself naturally to traditional engineering analyses. One engineering principle-the output response of a linear system to random signal-is applied here to explain the fact that there is measurable difference in the magnitude of the biological effectiveness when a given biological system is irradiated with two different radiation types of the same Linear Energy Transfer (LET).

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Three electronic personal dosimeters (EPD-N) manufactured by Siemens, serial numbers 0635, 0658, and 0683, were tested at the Radiation Calibration Laboratory for an evaluation of their response to neutron, gamma and x-ray radiation. Designed to provide real-time neutron and photon dosimetry, the EPD-N is capable of estimating and displaying neutron and gamma dose components separately for a range of energies from 50 keV to 7 MeV for photon and 0.025 eV to > 10 MeV for neutron. All tests were conducted using the factory calibrations. A technical representative of the manufacturer indicated that site-specific calibrations are required as factory settings are calibrated for the lowest neutron energy limit of 0.025 eV. This raises concerns about the reliability of these devices in measuring neutrons when calibrations are made for a specific site radiological characterization then used at another site.

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A brain weight deficit of about 70 mg was induced at doses of approximately 75-mGy and a deficit of 60 mg was induced at 100 mGy. This confirms the effects projected and observed by Wanner and Edwards. Although the data do not demonstrate a clear dose-response relationship between the 75-mGy and 100-mGy groups, the data are statistically consistent with a dose-response effect because of the overlapping confidence intervals. The lack of a statistically significant observation is most likely related to the small difference in doses and the limited numbers of animals examined. There are several factors that can influence the brain weight of guinea pig pups, such as caging and housing conditions, the sex of the animal, and litter size. These should be taken into account for accurate analysis. Dam weight did not appear to have a significant effect. The confirmation of a micrencephalic effect induced x rays at doses of 75-mGy during this late ...

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The X-ray photoacoustic spectra of copper and brass (64.7 wt.% Cu and 35.3 wt.% Zn) have been measured at XANES (X-ray absorption near-edge structure) regions using synchrotron radiation. These spectra were compared with optical density of X-ray spectra. It is shown that the information derived from XANES is also included in the X-ray photoacoustic spectrum which reflects the heat production processes in copper and brass. However, the results showed that the increases and changes of the photoacoustic signal were different from those of the X-ray absorption coefficient at XANES regions. (author).

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The document represents a guide for the external decontamination of persons accidentally radio contaminated due to the use, production or transport of radioactive materials. The general conditions, from the medical point of view, to be kept in mind, in the event of accidental overexposures as decontamination treatment and the handling of samples are detailed throughout report. The external contamination without injury in skin or with wound its considered. The distribution of measures and responsibilities for the therapy of the irradiated patients with radioactive materials are enumerated. The preparations of decontaminate solutions are detailed in this work. Moreover, forms for the reception, physical evaluation of the patient and external contamination are presented. (author)

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In situ assembly states of rat adipocyte glucose transport protein in plasma membrane (PM) and in microsomal pool (MM) were assessed by measuring target size (TS) of D glucose-sensitive, cytochalasin B binding activity. High energy radiation inactivated the binding in both PM and MM by reducing the total capacity of the binding (B/sub T/) without affecting the dissociation constant (K/sub D/). The reduction in B/sub T/ as a function of radiation dose was analyzed based on classical target theory, from which TS was calculated. TS in the PM of insulin-treated adipocytes was 58 KDa. TS in the MM of noninsulin-treated and insulin-treated adipocytes were 112 and 109 KDa, respectively. With MM, however, inactivation data showed anomalously low radiation sensitivities at low radiation doses showing a shoulder in the semilog plots, which may be due to an interaction with a radiation ...

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The development of a flat response small size, real time neutron dosimeter and ratemeter for the energy range of about 1 eV to 14 MeV is presented. This dosimeter is adequate for measuring neutron dose equivalents of 3 mRem up to 100 Rem and dose rates of 300 mRem/h to 50 Rem/h or more. The dosimeter consists of four Si surface barrier detectors. _1_0B radiators are placed in front of three of the detectors and a polyethylene radiator is placed in front of the fourth one. The _1_0B pellets are used for dose equivalent measurements in the energy range 1 eV to proportional1 MeV. The polyethylene radiator, made in two parts having thicknesses of 10 and 100 mg/cm_2 in an area ratio of 8 to 1, flattens the response to +-40% in the energy range 1-14 MeV. The signal-to-background ratio for different Si surface barrier detectors and for _1_0B polyethylene radiators was ...

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... organizations irradiation radiation doses radiation effects RADIATIONS.

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... halogenation ionizing radiations kinetics radiations reaction kinetics

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The results of a scoping study of onsite radiation exposures which could take place in each of three types of postulated reactor accidents are presented. The accident types are (1) a fuel handling accident at a Mark III BWR; an interfacing system LOCA or V sequence at a PWR; and and Anticipated Transient Without Scram (ATWS) at a Mark I BWR. Both external and internal dose pathways are considered. The results of the study indicate the prohibitively high radiation doses could be received in some plant areas if personnel were to remain there. However, times of the order of a few minutes to a few hours, depending on the type of accident, would be available before life-threatening doses would be accumulated assuming that the provided full face respiratory protection equipment were used promptly. Special attention was given radiation doses possibly received by control room personnel for several control room air in-leakage ...

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Purpose: To determine if involved field radiation (IF) is equivalent to standard whole bone radiation (SF) in local tumor control; to establish patterns of failure following treatment; and to determine response, event-free survival (EFS), and overall survival rates from multidisciplinary therapy in Ewing's sarcoma. Methods and Materials: Between 1983 and 1988, 184 children with Ewing's sarcoma were enrolled onto Pediatric Oncology Group 8346 (POG 8346). A total of 178 (97%) met eligibility criteria; 6 had pathology other than Ewing's sarcoma. Induction chemotherapy of cyclophosphamide/doxorubicin (adriamycin )(C/A) x 12 weeks was followed by local treatment either surgery or radiation therapy and C/A, dactinomycin, and vincristine for 50 weeks. Resection was advised for patients with small primary tumors if accomplished without functional loss. Forty patients were randomized to receive SF, whole bone ...

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CBA/Ca mice were infected by either the intravenous or intraperitoneal route with Mycobacterium microti and the subsequent changes in local macrophage populations examined. Following infection, the number of macrophages increased and they showed greater expression of both MHC Class II molecules. This response was not dependent on viability of the mycobacteria, in contrast to reports with other microorganisms such as Listeria. Studies in sublethally irradiated mice indicated that persistent antigen could give rise to a response after a period of host recovery which was radiation dose dependent. This procedure also highlighted differences in the regulation of different murine class II antigens in vivo, as seen by delayed re-expression of I-E antigens. Macrophage accessory cell function, as assessed by an in vitro T cell proliferation assay, correlated with Ia expression after fixation, but not after indomethacin treatment; ...

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To evaluate the predictive factors for treatment response and prognostic factors affecting survival outcomes after concurrent chemoradiotherapy (CCRT) for patients with anal squamous cell carcinoma. Medical records of forty two patients with histologically confirmed analsquamous cell carcinoma, who had complete CCRT between 1993 and 2008, were reviewed retrospectively. Median age was 61.5 years (39-89 years), and median radiotherapy (RT) dose was 50.4 Gy (30.0-64.0 Gy). A total of 36 patients had equal to or less than T2 stage (85.7%). Fourteen patients (33.3%) showed regional nodal metastasis, 36 patients (85.7%) were treated with 5-fluorouracil (5-FU) plus mitomycin, and the remaining patients were treated by 5-FU plus cisplatinum. The median follow--up time was 62 months (2-202 months).The 5-year overall survival, locoregional relapse-free survival, disease-free survival, and colostomy-free survival rates were 86.0%, 71.7%, 71.7%, 78.2%, respectively. Regarding ...

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Faced with increasing indications for the use of iodine-131 labelled lipiodol in the treatment of hepatocellular carcinoma (HCC), it appears essential to develop an individualized dosimetrY so we can predict the potential effectiveness of this treatment and adjust the activity to be injected. We developed a dosimetric protocol based on imagery and dedicated to calculation of the tumoral dose during the treatment of hepatocellular carcinoma by iodine-131 labelled lipiodol. This concept was developed on a SPECT- CT gantry, and integrates corrections for the phenomena of attenuation, diffusion and dead time. The dose is calculated according to the formalism proposed by the Medical Internal Radiation Dose Committee (MIRD). This protocol was applied to a series of 41 patients in the framework of a retrospective study. The results obtained in terms of biodistribution are compatible with previously published data. The total biological response rate is ...

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A computer model of cryogenic system for storing solid antimatter is used to explore the radiative cooling-power requirements for long-term antimatter storage. If vacuum-chamber pressures as low as 10 to -18th power torr can be reached, and the rest of the large set of assumptions is valid, milligram quantities of solid antimatter could be stored indefinitely at 1.5 K using cooling powers of less than a microwatt. Many of the assumptions made are problematic and need verification, as they could potentially change the results greatly. The system modeled is a sphere of solid anti-parahydrogen at 1.5 K or below levitated in a spherical cryogenic vacuum chamber. The free matter gas in the chamber is assumed to be molecular hydrogen, and sublimation of both matter and antimatter is assumed to be negligible. The antihydrogen is assumed to be in thermal equilibrium, although annihilation-energy deposition is localized and hydrogen's thermal-impulse ...

International Nuclear Information System (INIS)

The University of Michigan (UM) is a member of a team of researchers, including the universities of Florida, Texas, and Tennessee, along with Oak Ridge National Laboratory, developing robotic for hazardous environments. The goal of this research is to develop the intelligent and capable robots which can perform useful functions in the new generation of nuclear reactors currently under development. By augmenting human capabilities through remote robotics, increased safety, functionality, and reliability can be achieved. In accordance with the established lines of research responsibilities, our primary efforts during 1991 will continue to focus on the following areas: radiation imaging; mobile robot navigation; three-dimensional vision capabilities for navigation; and machine-intelligence. This report discuss work that has been and will be done in these areas.

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Simulations of the x-ray free-electron laser (FEL) oscillator are presented that include transverse effects and realistic Bragg crystal properties with the two-dimensional code GINGER. In the present cases considered the radiation divergence is much narrower than the crystal acceptance, and the numerical algorithm can be simplified by ignoring the finite angular bandwidth of the crystal. In this regime GINGER shows that the saturated x-ray pulses have 109 photons and are nearly Fourier-limited with peak powers in excess of 1 MW. Wealso include preliminary results for a four-mirror cavity that can be tuned in wavelength over a few percent, with future plans to incorporate the full transverse response of the Bragg crystals into GINGER to more accurately model this tunable source.

British Library Electronic Table of Contents (United Kingdom)

A study was conducted to determine the fitting soil moisture for the normal growth of two-year-old W. sinensis (Sims) Sweets by using gas exchange technique. Remarkable threshold values of net photosynthetic rate (Pn), transpiration rate (Tr) and water use efficiency (WUE) were observed in the W. sinensis leaves treated by various soil moisture and photosynthetic available radiation (PAR). The fitting soil moisture for maintaining a high level of Pn and WUE was in range of 15.3%?26.5% of volumetric water content (VWC), of which the optimal VWC was 23.3%. Under the condition of fitting soil moisture, the light saturation point of leaves occurred at above 800?mol?m?2?s?1, whereas under the condition of water deficiency (VWC, 11.9% and 8.2%) or oversaturation (VWC, 26.5%), the light saturatio...

International Nuclear Information System (INIS)

Shadow effect was used for investigating damage of uranium dioxide monocrystal. The dependence of shadow minimum parameters on fluence of "2"2Ne ions with 172 MeV energy was followed when detecting fission fragments. Ion dose responsible for sufficient microdamage of lattice structure, included into the classification of heavy ion damage effect on monocrystals was determined. The problem of radiation intensity effect on the character of occurred damages was studied. It was established that macroscopic sample failure, caused by generation of considerable mechanical stresses in monocrystal under beam effect could be observed along with microdamages of lattice structure at ion flux density >10"1"2 cm"-"2Xs"-"1.

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We have developed a flexible radioactive polyurethane patch incorporating {beta}-emitting radionuclide (166Ho) to treat malignant skin lesions. We covered the tumor surface (n=133) with the radioactive patch for 33.58 {+-} 5.33 minutes. Radiation dose delivered was 35 Gy for Bowen's disease (n=78), Kaposi sarcoma (n=25), actinic keratosis (n=5), and 50 Gy for BCC (n=17) and squamous carcinoma (n=8). Complete response was observed in 91.7% after the first therapeutic trial, 96.2% after 2nd and 97.7% after 4th trial with excellent cosmetic outcome for 31.15{+-}13.88 months of follow-up. Radioactive patch therapy is effective for superficial skin cancers that are impractical for surgery.

Energy Technology Data Exchange (ETDEWEB)

We have observed significant differences in the response to ionizing radiation of two closely related human cell lines, and now compare the effects on these lines of both low and intermediate LET radiation. Compared to TK6, WTK1 has an enhanced X-ray survival, and is also more resistant to cell killing by {alpha}-particles. The hprt locus is more mutable in WTK1 than in TK6 by both X-rays and {alpha}-particles. WTK1 is also more mutable by {alpha}-particles than by X-rays at the hprt locus. X-ray-induced mutation at the heterozygous tk locus in WTK1 is about 25 fold higher than in TK6, while {alpha}-particle-induced mutation is nearly 50 fold higher at this locus. Also, the slowly growing tk- mutants, which comprise the majority of spontaneous and X-ray-induced tk- mutants of TK6, were not induced significantly by {alpha}-particles. Previously, we showed that TK6 has a reduced capacity for recombination compared with WTK1, ...

UK PubMed Central (United Kingdom)

Abstract The authors provide a survey of how images are used in radiation therapy to improve the precision of radiation therapy plans, and delivery of radiation treatment. In contrast...Full Text Available

Environmental Research Database

No further description is available

International Nuclear Information System (INIS)

This chapter provides an overview of the problem of response to a nuclear weapon accident, the fundamentals of response to an accident, and a summary of the NARP Manual. The manual provides a summary of procedural guidance, technical information, and DoD responsibilities, to assist DoD forces in preparing a response to a nuclear weapon accident.

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Ketamine-anesthetized Sprague-Dawley rats were exposed in H orientation to far-field 9.3-GHz continuous-wave (CW) and pulsed (2 microseconds 500 pps) radiofrequency radiation (RFR) at average power densities of 30 and 60 mW/sq. cm (whole-body average specific absorption rates of 9.3 and 18.6 W/kg, respectively). Irradiation was conducted to cyclicly increase colonic temperature from 38.5 to 39.5 C. Colonic, tympanic, and subcutaneous temperatures, ECG, blood pressure, and respiratory rate were continuously recorded during experimentation. At both power densities, the subcutaneous and tympanic temperature increases significantly exceeded the colonic temperature increase. At both exposure levels, heart rate increased significantly during irradiation and returned to baseline when exposure was discontinued. Blood pressure and respiratory rate did not significantly change during irradiation. There were no significant differences between the effects of CW and pulsed RFR ...

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Many thermoluminescent materials has been developed and used for photon personal dosimetry but no one has all desired characteristics alone. These characteristics include robustness, high sensitivity, energy photon independence, large range of photon energy detection, good reproducibility, small fading and simple glow curve with peaks above 150 deg C. Calcium Sulfate Dysprosium doped (CaSO{sub 4}:Dy) phosphor Thermoluminescent Dosimeter (TLD) has been used by many laboratories, mainly in Brazil and India. Another interesting phosphor is Calcium Fluoride (CaF{sub 2}). These phosphor advantages begin to be more required and its disadvantages have became more apparent, in a global market more and more competitive. These phosphors are used in environmental and area monitoring, once they present more sensibility than other phosphors, like LiF:Mg. Theirs mainly disadvantage is a strong energetic dependence response, which must be corrected for theirs application in the ...

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Consensus principles from radiation biology were used to describe a generic set of nonlinear, first-order differential equations for modeling of toxicity-induced compensatory cell kinetics in terms of sublethal injury, repair, direct killing, killing of cells with unrepaired sublethal injury, and repopulation. This cellular model was linked to a probit model of hematopoietic mortality that describes death from infection and/or hemorrhage between {approximately} 5 and 30 days. Mortality data from 27 experiments with 851 doseresponse groups, in which doses were protracted by rate and/or fractionation, were used to simultaneously estimate all rate constants by maximum-likelihood methods. Data used represented 18,940 test animals distributed according to: (mice, 12,827); (rats, 2,925); (sheep, 1,676); (swine, 829); (dogs, 479); and (burros, 204). Although a long-term, repopulating hematopoietic stem cell is ancestral to all lineages needed to restore normal ...

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The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the only major protection to astronauts from harmful exposure. Unlike low-linear energy transfer (LET) {gamma} or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure, since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak. The Bragg curve does not necessarily represent the biological damage along the particle traversal, and the 'biological Bragg curve' is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. Here we used a unique irradiation geometry to measure the biological response across the Bragg curve in human fibroblasts exposed to ...

Energy Technology Data Exchange (ETDEWEB)

There is a continuing need to understand dose-response relationships for ionizing radiation in order to protect the health of the public and nuclear workers from undue exposures. However, relatively few human populations have been exposed to doses of radiation high enough to cause observable, long-term health effects from which to derive dose-response relationships. This is particularly true for internally deposited radionuclides, although much effort has been devoted to epidemiological studies of the few types of exposures available, including lung cancers in uranium miners form the inhalation of the radioactive decay products of Ra, liver cancers in patients injected with Thorotrast X-ray contrast medium containing Th, bone cancers in radium dial painters who ingested Ra, and bone cancers in patients who received therapeutic doses of Ra. These four types of exposures to internally deposited ...

International Nuclear Information System (INIS)

... radiation effects human populations low dose irradiation neoplasms radiation

International Nuclear Information System (INIS)

... defects doped materials germanium infrared radiation monocrystals neutron

International Nuclear Information System (INIS)

... pathological changes patients radiation protection radiotherapy diseases

International Nuclear Information System (INIS)

... compounds polymers polyolefins polyvinyls radiation effects SYNTHESIS.

CERN Document Server

Compact Proton and Carbon Ion Synchrotrons for Radiation Therapy

Energy Technology Data Exchange (ETDEWEB)

By the use of thermoluminescence (TL) technique we have investigated the effects of gamma irradiation on the TL response of pulverised natural zircon (ZrSiO{sub 4}) crystals from the Jos Plateau area of Nigeria. Samples of the mineral that have been previously annealed were artificially irradiated to moderate gamma doses ranging from 0.7 to 4.9 Gy using {sup 60}Co gamma-source of the CERD. The natural TL glow curve of the sample showed a broad peak around 250 deg. C, the peak was however, found to be completely erased following heat treatment for 2 h at 400 deg. C. The TL glow curves of the artificially irradiated samples showed two overlapping glow peaks at about 112 deg. C (peak I) and at 156 deg. C (peak II) within the dose range utilised. We note that the natural TL peak appears to be different from the two observed in the artificially irradiated sample. The TL response with dose was investigated for the two glow peaks found in the ...

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Systematics of neutron capture radiative width were studied in the target element range from Th to Cm. Reduced radiative widths were analyzed with a simple radiative width formula based on E1 transition. Average radiative width is presented with the standard deviation of 15%. (author)

International Nuclear Information System (INIS)

Patients with Ewing's sarcoma who present with a central axis or proximal extremity primary and/or with metastatic disease have a poor prognosis despite aggressive combination chemotherapy and local irradiation. In this high risk group of patients, total body irradiation (TBI) has been proposed as a systemic adjuvant. To aid in the design of a clinical TBI protocol, the authors have studied in the in vitro radiation response of two established cell lines of Ewing's sarcoma and human bone marrow CFUc. The Ewing's lines showed a larger D_0 and anti-n compared to the bone marrow CFU. No repair of potentially lethal radiation damage (PLDR) was found after 4.5 Gy in plateau phase Ewing's sarcoma cells. A theoretical split dose survival curve for both the Ewing's sarcoma lines and human bone marrow CFUc using this TBI schedule shows a significantly lower surviving fraction (10"-"4-10"-"5) for the bone marrow CFUc. Based on these ...

Energy Technology Data Exchange (ETDEWEB)

The clinical results of electron beam therapy using intraoral cone in 8 cases of primary and recurrence carcinoma of tongue (T1 and smaller T2) were reported. The primary and recurrence cases were 5 and 3, respectively. In the 5 cases, a total dose of 10-30 Gy external radiation therapy were combined prior to electron beam therapy. The total dose of electron beam therapy varied from 40 to 60 Gy. In all cases, tumor showed good response and disappeared clinically. Radiation stomatitis, pain of the tongue with masticatory disturbance due to tenderness were complicated in all cases. These complications gradually disappeared 2 to 6 months after treatment. However, loss of body weight and bone exposure were not recognized in any case. Intraoral-cone electron beam therapy is thought to be available and has less complications comparing interstitial irradiation therapy from the review of literature. Within 6 months after ...

Energy Technology Data Exchange (ETDEWEB)

Personnel radiation monitoring is essential to the operation of any nuclear facility and work in this area continues to strive for an accurate determination of personnel dose. In particular recent attention has been focused upon the need to improve the accuracy of neutron dosimetry, mainly because of their high Relative Biological Effectiveness. In this work the feasibility of using the NE-213 liquid scintillation detector as an efficient neutron/..gamma.. ray radiation monitor is demonstrated. Derivative method spectrum unfolding used in MATXUF for on-line analysis of fast neutron spectra has also been applied to real time ..gamma.. spectrum unfolding (MATXUF2), making possible simultaneous on-line monitoring of both fast neutrons and gammas. To eliminate the negative fluxes in the unfolded ..gamma.. spectra created by the photopeak-Compton edge combination in the plateau portion of the knee response, correcting equations ...

Science.gov (United States)

Personnel radiation monitoring is essential to the operation of any nuclear facility and work in this area continues to strive for an accurate determination of personnel dose. In particular recent attention has been focused upon the need to improve the accuracy of neutron dosimetry, mainly because of their high Relative Biological Effectiveness. In this work the feasibility of using the NE-213 liquid scintillation detector as an efficient neutron/gamma ray radiation monitor is demonstrated. Derivative method spectrum unfolding used in MATXUF for on-line analysis of fast neutron spectra has also been applied to real time gamma spectrum unfolding (MATXUF2), making possible simultaneous on-line monitoring of both fast neutrons and gammas. To eliminate the negative fluxes in the unfolded gamma spectra created by the photopeak-compton edge combination in the plateau portion of the knee response, correcting equations using a ...

Energy Technology Data Exchange (ETDEWEB)

Emerging high-power microwave technologies require that bioeffects of exposure to this type of radiation be investigated for health and safety considerations. Disruption of animal behavior is reported to be a sensitive indicator of microwave exposure. Three behavioral tasks were chosen for this initial investigation of exposure to U.S. Air Force high-power microwave emitters. The tasks were: (1) single-trail avoidance, (2) water satiation, and (3) rotarod performance. Exposure to high-power microwave radiation from the USAFSAM peak-power simulator significantly affected the single-trail avoidance task. Neither the single-trail avoidance task nor rotarod performance was affected by the Gypsy emitter. However, animals exposed to 9-kW and 11-kW outputs from the USAFSAM emitter spent significantly less time imbibing water postexposure than sham-exposed animals. The most consistent finding in the animals exposed to the Gypsy pulses was that those ...

Energy Technology Data Exchange (ETDEWEB)

The advanced detector development project at the University of Michigan has completed the first full year of its current funding. Our general goals are the development of radiation detectors and spectrometers that are capable of portable room temperature operation. Over the past 12 months, we have worked primarily in the development of semiconductor spectrometers with {open_quotes}single carrier{close_quotes} response that offer the promise of room temperature operation and good energy resolution in gamma ray spectroscopy. We have also begun a small scale effort at investigating the properties of a small non-spectroscopic detector system with directional characteristics that will allow identification of the approximate direction in which gamma rays are incident. These activities have made use of the extensive clean room facilities at the University of Michigan for semiconductor device fabrication, and also the radiation ...

International Nuclear Information System (INIS)

Full text: Thermoluminescence (TL) is a phenomenon of light emission caused by heating a pre-irradiated material. When ionizing radiation hits a TL material, electrons are freed from some atoms and moved in the material, leaving behind 'holes' of positive charge. Subsequently when the TL material is heated, the electrons and the 'holes' re-combine, and release the extra energy in the form of light. The light intensity can be measured, and related to the amount of energy initially absorbed through exposure to the ionizing radiation. In nineteen sixties thermoluminescence dosimeters (TLD) became popular for dosimetric applications in view of their small size, sensitivity and accuracy. Consequently, in early seventies, several countries started adopting of TLD for personnel monitoring. The idea of introducing TLD to replace the then prevalent film dosimeter for personnel monitoring in India was mooted and successfully implemented by Dr. K G Vohra. ...

Science.gov (United States)

PMID:19862292

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

German translation of the publication 'The evaluation of risks from radiation' published in 1965 by the International Commission on Radiological Protection. In a survey, genetic and somatic risks from radiation are presented and explained. (HP).

Science.gov (United States)

... mast cell staining; ref. 16). The severity of structural radiation injury was assessed using a histopathological radiation injury score ... ...

Science.gov (United States)

This investigation describes the technique for the detection of the X-ray fluorescent radiation

International Nuclear Information System (INIS)

Early effects of 100 Kilorads of X-rays on muscle cell membrane properties have been measured in sartorius muscles from Leptodactylus ocellatus. Threshold strength for rectangular current pulses increased 10% after irradiation, and action potential propagation velocity decreased 10%. Passive membrane parameters were calculated from potential responses to sub-threshold current pulses, assuming conventional cable theory. Specific membrane conductance increased to 18% after irradiation, membrane capacitance increased 14%, and length constant decreased 10% but membrane time constant was unchanged. Cell diameter decreased 5%, and resting membrane potential decreased 8%. Membrane parameters during an action potential were also evaluated by the phase-plane and current-voltage plot techniques. Irradiation significantly decreased the action potential amplitude, the excitation potential, and the maximum rates of rise and fall of membrane potential. Increases were observed in ...

International Nuclear Information System (INIS)

The process of ensuring the quality of computer codes can be very time consuming and expensive. The Oak Ridge National Laboratory (ORNL) Monte Carlo codes all predate the existence of quality assurance (QA) standards and configuration control. The number of person-years and the amount of money spent on code development make it impossible to adhere strictly to all the current requirements. At ORNL, the Nuclear Engineering Applications Section of the Computing Applications Division is responsible for the development, maintenance, and application of the Monte Carlo codes MORSE and KENO. The KENO code is used for doing criticality analyses; the MORSE code, which has two official versions, CGA and SGC, is used for radiation transport analyses. Because KENO and MORSE were very thoroughly checked out over the many years of extensive use both in the United States and in the international community, the existing codes were open-quotes baselined.close ...

Science.gov (United States)

The spectral dependences of absorption photoinduced in a pure bismuth titanium oxide crystal by 532-nm laser pulses are studied. It is shown that optical absorption in the crystal in the range from 492 to 840 nm increases with increasing exposure. The photoinduced absorption relaxes in the dark for more than 60 hours. A model of photoinduced absorption is proposed which assumes the population of two trap centres with the normal energy distribution law for the concentrations of electrons photoexcited from donors to the conduction band. This model well describes the spectral dependences of photoinduced absorption by using the average ionisation energies of the traps E{sub 1} = 1.60 eV and E{sub 2} = 2.57 eV. The model is used to estimate the increase in the photorefractive sensitivity of a bismuth titanium oxide crystal in the near IR region, which was earlier observed after exposing the crystal to visible radiation. It is predicted that the speed of ...

CERN Document Server

We present results from a large volume simulation of Hydrogen reionization. We combine 3d radiative transfer calculations and an N-body simulation, describing structure formation in the IGM, to detail the growth of HII regions around high redshift galaxies. Our simulation tracks 1024^3 dark matter particles, in a box of side length 65.6 Mpc/h. This large volume allows us to accurately characterize the size distribution of HII regions throughout most of the reionization process. At the same time, our simulation resolves many of the small galaxies likely responsible for reionization. It confirms a picture anticipated by analytic models: HII regions grow collectively around highly-clustered sources, and have a well-defined characteristic size, evolving from a sub-Mpc scale at the beginning of reionization to R>10 Mpc towards the end. We present a detailed statistical description of our results, and compare them with a numerical hybrid scheme ...

Science.gov (United States)

In response to the consultation from the National Council on Radiation Protection and Measurements (NCRP) to the International Commission on Radiological Protection (ICRP) committee 2, retention and excretion of 239Pu deposited at wound site were calculated by coupling together the proposed NCRP wound model and the current ICRP systemic model of Pu. The physicochemical forms considered were the soluble form categorized into 'Strong Retention', and the colloidal, particulate and fragmentary forms. The results are summarized as follows. If in soluble form, immediate medical intervention is needed to prevent uptake of radionuclides to body tissues, and prompt wound monitoring is essential for an accurate estimation of the initially deposited radioactivity. If in particulate form, a multi-component exponential equation leads to an overestimation of the absorption rate to blood because of significant lymph node drainage. The committed doses in the ...

Energy Technology Data Exchange (ETDEWEB)

The National Spallation Neutron Source (NSNS), in which neutrons are generated by bombarding a liquid mercury target with 1 GeV protons, will place extraordinary demands on materials performance. The target structural material will operate in an aggressive environment, subject to intense fluxes of high energy protons, neutrons, and other particles, while exposed to liquid mercury and to water. Components that require special consideration include the Hg liquid target container and protective shroud, beam windows, support structures, moderator containers, and beam tubes. In response to these demands a materials R and D program has been developed for the NSNS that includes: selection of materials; calculations of radiation damage; irradiations, post irradiation testing, and characterization; compatibility testing and characterization; design and implementation of a plan for monitoring of materials performance in service; and materials engineering ...

International Nuclear Information System (INIS)

Studies were undertaken to examine the effects of animal age on the anticarcinogenic properties of antioxidants. Female hairless mice, 2.5, 4.5 and 9.5 months of age, were subjected to daily irradiation from Westinghouse BZS-WLG lamps for 19 weeks. Experimental groups of animals were maintained on a commercial rodent meal supplemented with a 2% (w/w) antioxidant mixture. Control groups received only the meal. Tumour latency, expressed as median time to tumor development, was significantly greater for all age groups receiving antioxidants than for their similarly aged controls. However, the response to antioxidants appeared to decrease with age and the antioxidant effect was significantly less in the 9.5 month-old group than in the 2.5 month-old group. Likewise, the two youngest groups receiving antioxidants demonstrated a significantly fewer number of tumors per animal. It is concluded that animal age influences the degree of photoprotection provided by ...

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High-purity and doped GaAs films have been grown by Liquid-phase epitaxy (LPE) for development of a blocked impurity band (BIB) detector for far-infrared radiation. The film growth process developed has resulted in the capability to grow GaAs with a net active impurity concentration below 1 x 10{sup 13} cm{sup -3}, ideal for the blocking layer of the BIB detector. The growth of n-type LPE GaAs films with donor concentrations below the metal-insulator transition, as required for the absorbing layer of a BIB detector, has been achieved. The control of the donor concentration, however, was found to be insufficient for detector production. The growth by LPE of a high-purity film onto a commercially grown vapor-phase epitaxial (VPE) n-type GaAs doped absorbing layer resulted in a BIB device that showed a significant reduction in the low-temperature dark current compared to the absorbing layer only. Extended optical response was not detected, most ...

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A new method is being developed to quickly screen for the human exposure potential to polycyclic aromatic hydrocarbons (PAHs) and organochlorines (OCs). The development involves two key elements: identifying suitable signals that represent intracellular changes that are specific to PAH and OC exposure, and constructing a device to guide the biological cell growth so that signals from individual cells are consistent and reproducible. We are completing the identification of suitable signals by using synchrotron radiation-based (SR) Fourier-transform infrared (FTIR) spectromicroscopy in the mid-infrared region (4000-400 cm-1). Distinct changes have been observed in the IR spectra after treatment of human cells in culture medium with PAHs and OCs. The potential use of this method for detecting exposure to PAHs and OCs has been tested and compared to a reverse transcription polymerase chain reaction (RT-PCR) assay that quantifies increased expression of the CYP1A1 gene ...

International Nuclear Information System (INIS)

The feasibility of developing a fusion power monitor based on a fluid activation detector is considered here. The activation fluid may be either a liquid or a gas and its composition can be selected from a number of candidate materials to provide desired activation and decay characterisitcs. Performance calculations indicate that ordinary water would be a nearly ideal activation fluid. The "1"6O(n,p)"1"6N reaction has a threshold at about 10 MeV and a cross section energy dependence giving it a predominant response for unmoderated D-T fusion neutrons. Adequate activation can be obtained at moderate flow rates for remote counting away from the high radiation area of the reactor. The 7.16 sec half-life of "1"6N is ideal for remote counting with subsequent decay in a small hold-up tank to eliminate activity build-up in the recycled water.

Energy Technology Data Exchange (ETDEWEB)

Nuclear steam generator tubes have become flawed in ways that challenge conventional eddy current probes. In response to the shortcomings of conventional probes, array probes have been developed to improve measurement capabilities. However, the commercially available array probes have exhibited several weaknesses that offset the advantages and limit the applications in steam generator inspections. A primary weakness is the relatively high rate of probe failure coupled with the high unit cost for each probe. This can be costly for a utility in the time lost for probe replacement and increased radiation exposure in addition to the probe costs. Other weaknesses which make array probes undesirable for routine use are: poor mechanical and electrical characteristics; difficulty in operation and calibration; and incomplete coverage of the tube circumference. Several prototype array probes have been built to address the weaknesses of the commercially ...

Science.gov (United States)

Not Available

Wastenet

Subject to the provisions of the Radiation Protection Act, the Authority, on the advice of ...(f) in collaboration with the Radiation Protection Board, conduct an ionising radiation monitoring programme and ...or document kept under the control of the Radiation Protection Board.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

Described and discussed in this paper are radiation processes and their advantages over the conventional techniques. Radiation sterilization of medical products, food irradiation, wood plastic composites, and radiation treatment of sewage and waste waters are presented. The Philippine experience in using these technologies, its problems and barriers are also given. (ELC).

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

This text-book (electronic book - multi-media CD-ROM) constitutes a course-book - author's collection of lectures. It consists of 13 lectures in which the reader acquaints with the basis of radiobiology: Introduction to radiobiology; Physical fundamentals of radiobiology; Radiation of cells; Modification of radiation damage of cells; Reparation of radiation damage of cells; Radiation syndromes and their modification; Radiation injury; Radiation damage of tissues; Effect of radiation on embryo and fetus; Biological effects of incorporated radionuclides; Therapy of acute irradiation sickness; Delayed consequences of irradiation; Radiation oncology and radiotherapy. This course-book may be interesting for students, post-graduate students of chemistry, biology, physics, medicine as well as for teachers, scientific workers ...

Science.gov (United States)

Cervical Cancer; Radiation Toxicity

International Nuclear Information System (INIS)

... beam monitoring betatrons delay circuits errors fluctuations gamma radiation

Energy Technology Data Exchange (ETDEWEB)

The results of interstitial brachytherapy in 13 patients with malignant brain tumors (malignant glioma 9 cases, metastatic brain tumor 4 cases) were reported. In all patients, Ir-192 thin wires were implanted temporarily in afterloading catheters, which were implanted appropriately by means of MRI or CT guided stereotactic technique. Clinical results on CT scan were as follows: CR (complete response) 1 case, PR (partial response) 6 cases and NC (no change) 6 cases. Even in the NC group, tumor growth was inhibited temporarily. Tumor free intervals were ranged 2-17 months. In early series, the intervals were about 2 months due to incomplete arrangement of radioactive implants. In recent series, prolongation of tumor free interval more than 12 months was achieved due to precise arrangements of implants. MRI guided stereotactic interstitial brachytherapy may provide safe and precise intracranial arrangements of implants, which yield high ...

Energy Technology Data Exchange (ETDEWEB)

Several recent improved methods for the EGFM are introduced in order to avoid artificial holes seen in the synthetic acceleration spectrum. Furthermore evaluation of input ground motions at Wolsung NPP are performed by varying the source parameters that may control the high-frequency wave radiation and the deviation of the synthetic motions are revealed. The PSHA case studies for four NPP sites (Wolsung, Kori, Uljin, Younggwang) are performed. In the analysis, site-specific attenuation equations developed for Korean NPP sites are employed, and the seismic hazards for the target sites are evaluated in the case where the four kind of seismic source models are considered. Moreover, the PSHA for Wolsung and Younggwang are conducted by using the site-specific attenuation equation with the index of response spectra and the uniform hazard spectra are evaluated for the two sites. The supporting tool for seismic response analysis ...

Energy Technology Data Exchange (ETDEWEB)

From 1980 to 1993, the domestic production of uranium declined from almost 44 million pounds U{sub 3}O{sub 8} to about 3 million pounds. This retrenchment of the U.S. uranium industry resulted in the permanent closing of many uranium-producing facilities. Current low uranium prices, excess world supply, and low expectations for future uranium demand indicate that it is unlikely existing plants will be reopened. Because of this situation, these facilities eventually will have to be decommissioned. The Uranium Mill Tailings and Radiation Control Act of 1978 (UMTRCA) vests the U.S. Environmental Protection Agency (EPA) with overall responsibility for establishing environmental standards for decommissioning of uranium production facilities. UMTRCA also gave the U.S. Nuclear Regulatory Commission (NRC) the responsibility for licensing and regulating uranium production and related activities, including decommissioning. Because ...

Energy Technology Data Exchange (ETDEWEB)

As a central supervision authority the National Electrical Safety Board (Elsaekerhetsverket) has the main responsibility for the safety of high voltage power lines and other power electric equipment. It is therefore also responsible for questions concerning the effects of power frequency magnetic fields on the environment. According to the rules it is not allowed to draw overhead power lines with a voltage exceeding 1000 V above buildings. Their minimum distance to buildings must not be below 5 m. For regions comprised by rural development plans the directions prescribe a minimum distance of 10 m between buildings and high voltage transmission lines with a voltage of 55 kV or more. The publication of two large epidemiological studies about exposure to magnetic fields and cancer in Sweden in autumn 1992 has brought magnetic fields problems to general notice again. A statement on health risks form electromagnetic fields was issued by SSI in ...

Energy Technology Data Exchange (ETDEWEB)

A.C.R.O. (Association pour le Controle de la Radioactivite dans l Ouest) is a French non governmental organisation that operates a laboratory for radioactivity analysis. It was created in 1986 as a response to people demands for information and reliable, independent testing. The organisation mainly carries out missions of information and training for its correspondents and more generally for a wide audience, particularly for people who worry about problems of environment, health, management of radioactive waste and emissions. Thanks to its structure, it enables citizens to involve themselves together with scientists so as to gain access to information that was hither to reserved to specialists. The organisation can vouchsafe its independence from the diversity of its members and volunteers, as well as from the diversity of its money resources. Besides its headquarters situated on the city of Caen area (Normandy), three branches situated in North Normandy, in ...

Energy Technology Data Exchange (ETDEWEB)

Radio-biologists have pointed out a novel radiobiological phenomenon observed in many tumor and normal cell lines: hyper-radiosensitivity to very low-dose (H.R.S.) followed by induced radioresistance (I.R.R.) after a threshold dose of 0.1-0.3 Gy that depends on the cell line. Radioresistance at high dose (i.e. higher than 0.5 Gy) and metastatic potential of tumor cells are likely major factors of failure in radiotherapy. A careful review of literature suggests that: 1) radiotherapy does not increase the metastatic potential of tumor cells; 2) radioresistance at high dose and metastatic potential are not related. However, inside a given tumor cell line, highly metastatic clones may elicit more cells showing H.R.S; or are more radiosensitive at high dose than poorly metastatic ones. Recent data obtained from molecular techniques (comet and immunofluorescence assays) applied to single cells irradiated at very low radiation doses (1-100 mGy) suggest that DNA ...

Science.gov (United States)

Basic research of the structure and electronic properties of a-Si:H is reported with particular emphasis on the role of defects. The main findings are as follows: (1) low defect density material can be deposited at a high rate using SiH/sub 4/ diluted in He or Ne. Using Ar or Kr results in a high defect density and columnar material; (2) an electrical bias during deposition modifies the band gap, hydrogen concentration and structure; (3) the clustering of hydrogen in the regions between the columns is confirmed; (4) hydrogen diffusion is observed by NMR; (5) the oxidation of an a-Si:H surface results in approx. 3 x 10/sup 11/ cm/sup -2/ dangling bonds at the interface; (6) auger recombination of photoexcited carriers is a significant non-radiative mechanism at low temperatures; (7) non-radiative recombination by diffusion and capture at dangling bonds is observed at temperatures above 50 to 100/sup 0/K; (8) the defect density in doped and ...

International Nuclear Information System (INIS)

Present and potential future changes to the global environment have important implications for marine pollution and for the air-sea exchange of both anthropogenic and natural substances. This report addresses three issues related to the potential impact of global change on the air-sea exchange of chemicals: Global change and the air-sea transfer of the nutrients nitrogen and iron. Global change and the air-sea exchange of gases. Oceanic responses to radiative and oxidative changes in the atmosphere. The deposition of atmospheric anthropogenic nitrogen has probably increased biological productivity in coastal regions along many continental margins. Atmospheric deposition of new nitrogen may also have increased productivity somewhat in mid-ocean regions. The projected future increases of nitrogen oxide emissions from Asia, Africa and South America will provide significant increases in the rate of deposition of oxidized nitrogen to the central ...

International Nuclear Information System (INIS)

Some of the Indian pressurized heavy water reactors (PHWRs) which use Stellite balls in the ball and screw mechanism of the adjustor rod drive mechanism in the moderator circuit have encountered high radiation fields in the moderator system due to "6"0Co. Release of particulate Stellite is responsible for the hotspots in addition to the general uniform contamination of internal surfaces with "6"0Co. Extensive laboratory studies have shown that it is possible to dissolve these Stellite particles by adopting a three-step redox process with permanganic acid as the oxidizing agent. These investigations with inactive Stellite in powder form helped to optimize the process conditions. Permanganic acid was found to have the highest dissolution efficiency as compared to alkaline and nitric acid permanganate. The susceptibility of Stellite to corrode or dissolve was found to depend on the concentration of the permanganate, pH and temperature of the ...

Energy Technology Data Exchange (ETDEWEB)

This chapter is concerned with standards and guidances for limiting radiation exposures. It is divided into three sections, each of which has several parts. Section 1: Ionizing Radiation -- Standards and Guidances Applicable to the Public: Part A, Radiation Protection Standards; Part B, Environmental Radiation Standards; Part C, Exempt Levels of Radioactivity; Part D, Protective Action Guides for Accidents. Section 2: Ionizing Radiation -- Standards Applicable to the Workplace. Section 3: Medical and Other Standards.

International Nuclear Information System (INIS)

Purpose: We present an update analysis of the multiinstitutional Ewing's sarcoma study CESS 86. Methods and Materials: From January 1986 through June 1991, 177 patients with localized Ewing's sarcoma of bone, aged 25 years or less, were recruited. Chemotherapy consisted of four 9-week courses of vincristine, actinomycin D, cyclophosphamide, and adriamycin (VACA) in low-risk tumors (extremity tumors =# 100 cm"3). Local therapy was an individual decision in each patient and was either radical surgery (amputation, wide resection) or resection plus postoperative irradiation with 45 Gy or definitive radiotherapy with 60 Gy (45 Gy plus boost). Irradiated patients were randomized concerning the type of fractionation in either conventional fractionation (once daily 1.8-2.0 Gy, break of chemotherapy) or hyperfractionated split-course irradiation simultaneously with the VACA/VAIA chemotherapy (twice daily 1.6 Gy, break of 12 days after 22.4 Gy and 44.8 Gy, total dose and treatment time as for ...

International Nuclear Information System (INIS)

Purpose: To determine if involved field radiation (IF) is equivalent to standard whole bone radiation (SF) in local tumor control; to establish patterns of failure following treatment; and to determine response, event free (EFS) and overall survival rates from multi-disciplinary therapy in Ewing's Sarcoma (ES). Materials and Methods: Between 1983 and 1988, 184 children with ES were enrolled onto POG 8346. 178 (97%) met eligibility criteria; 6 had non-ES pathology. Induction treatment of Cyclophosphamide/Adriamycin (C/A) x 12 weeks was followed by local treatment either surgery or radiation therapy (XRT) and C/A, Dactinomycin and Vincristine for 50 weeks. Resection was advised for patients with small primary tumors if accomplished without functional loss. 40 patients were randomized to receive SF, whole bone XRT to 39.6 Gy plus a 16.2 Gy boost (total 55.8 Gy) or IF to 55.8 Gy while 84 were assigned to IF ...

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The assumed linear relationship between exposure to radiation and cancer incidence is questioned in this article. The current research data on radiation effects at the cellular level is reviewed, as are epidemiological studies of background radiation effects and health effects of populations exposed to low levels of radiation exposure via employment or medical treatments. Statistics reveal that threshold levels currently in force need to be reviewed. Some evidence of beneficial effects of low level radiation exposure effects of low level radiation exposure is also presented, and so regulations should be reviewed at an international level. (UK).

UK PubMed Central (United Kingdom)

Dependent variables in research on problem behavior typically are based on measures of response repetition, but these measures may be problematic when behavior poses high risk or when its occurrence...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundReplication capacity (RC) of specific HIV isolates is occasionally blamed for unexpected treatment responses. However, the role of viral RC in response to antiretroviral...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

An anomaly in the continuous X-ray (CXR) response of filled cables is described. A systematic investigation of this anomaly is pursued with a single cable type and a model explaining the anomaly is presented. The effect of the anomaly on the accuracy of CXR measurement of SGEMP response is discussed.

UK PubMed Central (United Kingdom)

BackgroundVariable platelet response to clopidogrel has been widely observed. Studies have shown that the mean aggregation response to clopidogrel can be changed...Full Text Available

UK PubMed Central (United Kingdom)

Cytokines produced by Th2 cells are responsible for the pathogenesis of asthma. Th1-biased immune responses caused by attenuated salmonella have the potential to relieve asthmatic symptoms. We evaluated...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The book examines current experimental and clinical knowledge concerning the biological and biophysical effects of electromagnetic radiation, particularly that in the microwave range. The biophysical bases of the interaction of electromagnetic radiation with matter are reviewed with emphasis on biological systems, and the effects of radiation on critical biological systems, including the nervous, reproductive, visual and blood-forming systems are compared. Data concerning the lethal effects of nonionizing radiation is presented and characteristics of the effects of electromagnetic radiation on the whole mammalian organisms are examined. Various reactions of the neuroendocrine system to electromagnetic radiation are described, with particular attention given to the adrenal system, and the combined effects of ionizing and microwave radiation ...

Science.gov (United States)

The experimental device for generation of undulator radiation in terahertz wavelength region by use of undulator with ferromagnets is created. The device is based on a beam of a microtron with the energy 7.5 MeV. The radiation wavelength is 200 mu. Registered spontaneous radiation has a power 10{sup -6} W at a current of a beam 2 mA in a pulse. With the optical resonator, in a mode, the amplification of 6% is received, that in sometimes is more than the expected value. This effect is explained as a result of partial coherence of radiation.

International Nuclear Information System (INIS)

Characteristics of the Ukrainian NSA NRI radiation facility for scientific researches and developments of industrial radiation technology are performed. Parts of the facility, design peculiarities of technical tools are described. Biological protection of the facility and radiation protection system, transport line, systems of technical provision and radiation measurements are discussed

CERN Document Server

High energy muon colliders, such as the TeV-scale conceptual designs now being considered, are found to produce enough high energy neutrinos to constitute a potentially serious off-site radiation hazard in the neighbourhood of the accelerator site. A general characterization of this radiation hazard is given, followed by an order-of-magnitude calculation for the off-site annual radiation dose and a discussion of accelerator design and site selection strategies to minimize the radiation hazard.

International Nuclear Information System (INIS)

Coherent oscillator radiation is considered. A comparison is made with classical particle radiation with gauss distribution. Decay probability for coherent state in spontaneous radiation is estimated. The method suggested for describing harmonic oscillator allows to separate the effect of classical field radiation from quantum description of particle state within the framework of a self-consistent quantum mechanical problem.

UK PubMed Central (United Kingdom)

Senescence is regarded as a physiological response of cells to stress, including telomere dysfunction, aberrant oncogenic activation, DNA damage, and oxidative stress. This stress response has an antagonistically...Full Text Available

UK PubMed Central (United Kingdom)

BACKGROUND: Cuba's response to the human immunodeficiency virus (HIV) epidemic has been to conduct mass testing of the population to ascertain seroprevalence, to enforce mandatory relative quarantine...Full Text Available

Science.gov (United States)

A new type of radiation which occurs when particles are accelerated in the field of a longitudinal wave and in a transverse magnetic field is studied. The characteristics of such spontaneous radiation are obtained, and the influence of collective effects on the radiation is analyzed. The application of the findings to the theory of free electron lasers is discussed. 8 references.

UK PubMed Central (United Kingdom)

Objectives To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental,...Full Text Available

International Nuclear Information System (INIS)

Exact anatomic knowledge about the location of the gonads and the application of corresponding measures of radiation protection are the preconditions for an efficient reduction of the danger of a possible genetic damage as a result of radiation exposition during X-ray examination of the hip joint of newborns. (VJ).

Science.gov (United States)

Analytical method of theoretical simulation of collective hydrodynamic instabilities of intensive flows of discrete radiators, interacting with each other only through the coherent fields of their spontaneous radiation in corresponding media was suggested...

International Nuclear Information System (INIS)

The different radiation loads caused by natural and artificial radionuclides are compared in this paper. This examples will serve to illustrate that the problem of population exposure to radiation can only be solved in consideration of all components and to show which effects of the radiation from natural sources are of special importance in this connexion. (orig./AK).

Energy Technology Data Exchange (ETDEWEB)

The fundamental recommendations of the ICRP issued in its publication of 1990 stipulate the general principle of performance of dose measurements at regular intervals in the field of diagnostic radiology, for the purpose of equipment performance checking and optimization of radiological protection. In response to this requirement, the Federal Ministry, in cooperation with experts and the competent supervising authorities, has issued an order to install dose-area-product meters in angiographic examination systems, imaging systems and fluoroscopic screen devices primarily used for examining infants and children up to the age of 12. This is done in response to reported cases of adverse effects of radiation exposure and the high priority given to radiological protection in the examination of infants and children. In 1992, an expert group was convened to discuss and elaborate instructions for including dose-area product ...

International Nuclear Information System (INIS)

Thirty-seven patients with primary nonresectable intrahepatic cholangiocarcinoma (57% with prior treatment and/or metastasis) were prospectively treated with external radiation, chemotherapy, and "1"3"1I labelled anti-CEA. Therapy began in all trials with whole liver irradiation (21.0 Gy, 3.0 Gy/Fx, 4 days/week, 10 MV photons) with alternate treatment day chemotherapy (Adriamycin, 15 mg + 5-FU, 500 mg). One month after external beam therapy, chemotherapy was given (Adriamycin, 15 mg + 5-FU, 500 mg) followed the next day by the first administration of "1"3"1I anti-CEA. The treatment schedule used was 20 mCi day 0; 10 mCi day 5 as an outpatient. This schedule was derived from tumor dose estimates which indicated that 20 mCi (8-10 mCi/mg IgG) was sufficient to achieve tumor saturation with a tumor effective half-life of 3 to 5 days, depending upon the species of animal from which the antibody was obtained. The median tumor dose for the 20 mCi + 10 mCi regimen was 6.2 ...

International Nuclear Information System (INIS)

An optical klystron is built in the 800 MeV electron storage ring at University of Science and Technology of China for harmonic super-radiation generation. In single bunch operation mode the repetition rate of the spontaneous radiation pulses is about 4.533 MHz, and the repetition rate of the seed laser pulses is about 3 Hz, while the radiation pulse duration is 300 ps. For measuring harmonic radiation a high on/off ratio ICCD is used as an optical switch to reject spontaneous radiation pulses of high repetition rate

Science.gov (United States)

Mar 1, 2011 ... Radionuclide X-ray fluorescence analysis. 2: Detection of the X-ray fluorescence radiation excited by radionuclide radiation ...

Energy Technology Data Exchange (ETDEWEB)

The report gives general principles of treatment and care of casualties caused by radiation accidents or nuclear explosions.

International Nuclear Information System (INIS)

... bollworm fertility gamma radiation genetic radiation effects life span mating

Science.gov (United States)

drical Enclosures Using a Numerical Ray Tracing Technique. NASA. TM-I02527, 1990 . Buckley, H.: Radiation from the Interior of a Reflecting Cylinder. Philos. ...

Energy Technology Data Exchange (ETDEWEB)

The fundamental product of tetracycline hydrochlorine gamma radiolysis was separated in its solid state. From the results of spectroscopic studies it has been established that it is des-N,N-dimethylaminotetracycline.

Science.gov (United States)

the probability of its spontaneous radiation de-excitation increases. ... consider spontaneous radiation transitions. We will examine the ...

International Nuclear Information System (INIS)

Turbulent premixed methane-air combustion in a cylindrical chamber is numerically simulated considering radiation effect. Reaction rates are considered as minimum rates between Arrhenius rates and eddy break up rates. A five step reduced mechanism is used. Turbulent modeling is done via standard k-? model imposed by empirical inlet boundary conditions. Source terms of energy equation consist of reaction rates and radiation effects. The discrete ordinate method (DOM) is employed to solve the radiative transfer equation (RTE) and the weighted sum of gray gas model (WSGGM) is imposed to consider radiation effect of non-gray gases. The results indicate that in the case of turbulent combusting flows, the effect of radiation of gases can affect the temperature and species concentrations. The numerical results obtained considering radiation effect are closer to the ...

Science.gov (United States)

... iFfficiency-en- enhanced spontaneous radiation at the free-electron- ... as enhanced spontaneous radiation at the free-electron-laser wavelength. ...

International Nuclear Information System (INIS)

... EFFECT OF GAMMA RADIATION AND BAG PACKAGING MATERIALS ON

CERN Document Server

Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy

Science.gov (United States)

... spontaneous radiation of amplifiers within a relatively w~de range of ... pulse widths are 20-30ns, while amplified spontaneous radiation pulse ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

vibration Isolation system for the camera. ... to further define the response of the camera vibration isolation system. These ...

KoreaScience (Korea)

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KoreaScience (Korea)

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Norwegian Open Research Archives (NORA)

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KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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Science.gov (United States)

ice could be responsible for the formation of martian gullies. Tomorrow's picture: whirlpool ...

Energy Technology Data Exchange (ETDEWEB)

In this effort, the nonlinear responses and stability of a spindle system supported by ball bearings are presented. The dynamics of this system is described by a set of second order differential equations with a nonlinear piecewise smooth force. The Floquet theory is applied to investigate the stability of the periodic solution. Due to the loss of contact between the raceways and balls in the ball bearing, the bending of the frequency response curves switch to the left at the weak resonance region, which is similar to the frequency response curves of a system with a soft spring. With the decrease of the bearing clearance, the bending of the frequency response curves switch to the right, which is similar to the frequency response curves of a system with a hard spring. Increase of the frequency ratio, the bending of frequency response curves transforms from left ...

International Nuclear Information System (INIS)

Full text: It is known that the ion implantation of germanium single crystals at room temperature results in drastic alteration of the germanium surface and the formation of cellular relief. Voids were found into the near-surface damage layer. The intersection of these voids with the germanium surface, as result of sputter etching, forms cellular relief. However, exact mechanism responsible for formation of the voids is not known. A 10 and 30 keV Ga"+ irradiation of Ge #left brace#100#right brace# crystal at room temperature was carried out using a focused ion beam (FIB) system with a dose in the range 0.5x10"1"2 to 1.5x10"1"4 ion/cm"2. The topology of the modified germanium surface and the structure of the radiation damage was studied using imaging facilities of the FIB systems and transmission electron microscopy. The strong cellular structure of Ge was observed after an ion dose of 3x10"1"3 ion/cm"2. High-resolution TEM showed a complex ...

Energy Technology Data Exchange (ETDEWEB)

In this work tests of quality control in beams of X rays have been carried out, at diagnostic level, of two radiological services equipments of Brazilian hospitals (Aracaju, SE). We obtained the air kerma and kerma rate values, the beams efficiency, the coherence between the luminous fields and the referring fields of irradiation and half-value layer to each equipment and set of parameters. The measures of direct form have been obtained using two ionization chambers, one cylindrical and another one with parallel plates. An optional method for accomplishment some of the tests were carried out with CaSO{sub 4}:Dy + Teflon thermoluminescent dosimeters. The values of air kerma were evaluated for three tube voltage, 40, 60 and 81 kV at 1.0 m from the focus of the equipments. For each one of the voltages three distinct current values were chosen besides a fixed value of exposition time. The results showed that the values of air kerma varied between 8.0 {mu}Gy and 0.35 {mu}Gy. The T.L.D. have ...

DEFF Research Database (Denmark)

Functional magnetic resonance imaging (fMRI) in young children may provide information about the development of the visual cortex, and may have predictive value for later visual performance. The purpose of this study was to evaluate the usefulness of fMRI for examining cerebral processing of vision in very young infants and in infants with brain damage. We examined 15 preterm infants, 12 children suspected of having a cerebral visual impairment and 10 children with a normal visual system, all of whom were either spontaneously asleep or sedated with chloral hydrate. Cortical response to stroboscopic light stimulation could be demonstrated in all technically acceptable data sets from children with a post-menstrual age (PMA) of > 41 weeks, but not in younger infants. Children < 60 weeks PMA showed either a blood oxygenation level-dependent (BOLD) signal increase or decrease, while all older children showed a signal decrease. The activated cortical volumes showed ...

Energy Technology Data Exchange (ETDEWEB)

The proton beam has a unique advantage over the electron and photon beams in that it can give very high radiation dose to the tumor volume, while effectively sparing the neighboring healthy tissue and organs. For the clinical application of the proton beam, it is very important to confirm the location of the proton beam in the patient, preferentially during the treatment. It has been suggested that the range of the proton beam in the patient can be determined by measuring prompt gammas from the proton beam passage. Recently, a prototype prompt-gamma scanning system has been constructed and tested using experimental and therapeutic proton beams. The measurement results for the proton beams of 70 . 230 MeV showed that a clear correlation exists between the distribution of the prompt gammas and the proton beam range. The scanning method, however, is not suitable for the upcoming 'spot scanning' technique. The 'spot scanning' ...

Science.gov (United States)

We describe the development of a fully coupled climate model configuration where the Community Climate System Model (CCSM) has been coupled with the VERDE (Visualizing Energy Resources Dynamically on the Earth) analysis modules that compute the response of the electric grid to temperature drivers. The VERDE model includes datasets characterizing the 26,500 sub-stations and 6,000 power generation stations fuel mix, efficiency, service areas, and future performance and these have been geo-located on a 1.4 degree latitude by 1.4 degree longitude CCSM grid (T85). The total electric customers have been computed using conversions derived from economic structure and population data. The carbon emissions per customer and the power generation in megawatts electric (MWe) have also been placed on reconciled 1 km, 4 km and the T85 climate model grid. The CCSM temperature for the present and future have been extracted from the climate model output and placed on the same grid as ...

International Nuclear Information System (INIS)

Studies that estimate deficit probabilities in hydrothermal systems have generally ignored the response of demand to changing prices, in the belief that such response is largely irrelevant. We show that ignoring the response of demand to prices can lead to substantial over or under estimation of the probability of an energy deficit. To make our point we present an estimation of deficit probabilities in Chile's Central Interconnected System between 2006 and 2010. This period is characterized by tight supply, fast consumption growth and rising electricity prices. When the response of demand to rising prices is acknowledged, forecasted deficit probabilities and marginal costs are shown to be substantially lower. (author)

British Library Electronic Table of Contents (United Kingdom)

In modern quality engineering, dual response surface methodology is a powerful tool to model an industrial process by using both the mean and the standard deviation of the measurements as the responses. The least squares method in regression is often used to estimate the coefficients in the mean and standard deviation models, and various decision criteria are proposed by researchers to find the optimal conditions. Based on the inherent hierarchical structure of the dual response problems, we propose a Bayesian hierarchical approach to model dual response surfaces. Such an approach is compared with two frequentist least squares methods by using two real data sets and simulated data.

International Nuclear Information System (INIS)

... v. 1267(1) RADIATION CHEMISTRY, RADIOCHEMISTRY AND NUCLEAR

Energy Technology Data Exchange (ETDEWEB)

The book is divided into two approximately equal parts. The first four chapters are relatively lengthy and cover the basic principles of radiation biology, carcinogenesis and therapy, along with a brief introduction to radiological physics to orient the reader without background in this specialized related discipline. The remainder consists of twenty-four relatively brief chapters, each covering the radiation biology of a specific organ, tissue, or systems tissues, with emphasis on the tumorigenic and tumoricidal action of ionizing radiations.

Energy Technology Data Exchange (ETDEWEB)

Short communication. 5 refs., 2 figs.

International Nuclear Information System (INIS)

... VDPEAZ (Bonn 2010 issue) NUCLEAR PHYSICS AND RADIATION PHYSICS

KoreaScience (Korea)

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Science.gov (United States)

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International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

Disclosed herein is a radiation detector providing for the in situ automatic sampling of fluids containing substances emitting radiation, especially Cerenkov radiation. The detector permits sampling within well casings and is self-purging such that no additional provisions must be established for the storage and disposal of contaminated fluids.

Energy Technology Data Exchange (ETDEWEB)

A brief guide to training and equipment needed to effectively manage victims of radiation accidents. (DT)

Science.gov (United States)

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International Nuclear Information System (INIS)

A study is made of the mechanical properties of vanadium irradiated with fast neutrons up to dose 8.6.10"-"4 dpa, as a function of the temperature of post-radiation annealing. The radiation-annealing hardening (RAH) effect is observed at 300"oC, in agreement with previous studies. It is established for the first time that RAH is accompanied by fall in ductility. A phenomenological model is described which explains the dependence of RAH on radiation dose and temperature, as well as on the content of chemically active alloying impurities. (author).