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Includes indexes. ; NTIS Accession no. DE84010667 ; Government Reports Announcements , ; Mode of access: Internet.

Ultraviolet radiation dosimetry was determined by using CN-85 , CR-39 ,LR-115 nuclear track detectors – NTD with measuring of ; number of track-NT , etching time-TB , nuclear track diameter - DT and etching velocity -VD . By this study appear the increasing in etching time-TB of NTD samples which irradiated by UV-radiation do not pure effect on the number of track - NT , comparing with un-irradiated samples . The increasing in UV-irradiation make decreasing in etching time- Topt for CR-39 , CN-85 , LR-115 nuclear track detectors with percent of 20% , 25% , 50% respectively , comparing with un– irradiated sample at the radiation dose 3.77x103 erg /mm2 . . The increasing of irradiation dose make increasing in nuclear track diameter-DT with increase in etching time-TB at the radiation dose 300x103erg / mm2 for LR-115 detector . This study showing there was increasing in the percent value of etching velocity -VB with increasing inradiation dose for CR-39 , CN-85 . The increasing in nuclear track diameter- DTwith increasing in radiation dose was appearing as a resulted of energy of radiationand producted free radicals which interact with chemical etching solution . Thisstudy optioned by using nuclear track detectors CN-85 , CR-39 for determinationthe radiation dosimetry through measuring of etching velocity -VB butter than LR-115 detector

Historically, the development of computational phantoms for radiation dosimetry have primarily been directed at capturing and representing adult and pediatric anatomy, with less emphasis devoted to models of the human fetus. As concern grows over possible radiation-induced cancers from medical and non-medical exposures of the pregnant female, the need to better quantify fetal radiation doses, particularly at the organ-level, also increases. Studies such as the European Union's SOLO (Epidemiological Studies of Exposed Southern Urals Populations) hope to improve our understanding of cancer risks following chronic in-utero radiation exposure. For projects like SOLO, currently available fetal anatomic models do not provide sufficient anatomical detail for organ-level dose assessment. To address this need, two fetal hybrid computational phantoms were constructed using high-quality magnetic resonance imaging (MRI) and computed tomography (CT) image sets obtained for two well-preserved fetal specimens aged 11.5 and 21 weeks post-conception. Individual soft tissue organs, bone sites, and outer body contours were segmented from these images using 3D-DOCTORTM and then imported to the 3D modeling software package RhinocerosTM for further modeling and conversion of soft tissue organs, certain bone sites, and outer body contours to deformable non-uniform rational B-spline (NURBS) surfaces. The two specimen-specific phantoms, along with a modified version of the 38-week UF hybrid newborn phantom, comprised a set of base phantoms from which a series of hybrid computational phantoms was derived for fetal ages 8, 10, 15, 20, 25, 30, 35 and 38 weeks post-conception. The methodology used to construct the series of phantoms accounted for the following age-dependent parameters: (1) variations in skeletal size and proportion, (2) bone-dependent variations in relative levels of bone growth, (3) variations in individual organ masses and total fetal masses and (4) statistical percentile variations in skeletal size, individual organ ...

"Operation Plumbbob, Nevada Test Site, May-October 1957." ; "Civil Effects Test Group."--Cover. ; "Project 37.5." ; "WT-1493 ; AEC Category: Health and Safety ; Military Categories: 22 and 28"--Cover. ; "Issuance Date: February 20, 1961"--Cover. ; "July 1960." ; At head of title: Report to the Test Director. ; Includes bibliographical references. ; Mode of access: Internet. ; This bibliographic record is available under the Creative Commons CC0 "No Rights Reserved" license. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.

Comparative Dosimetry of Radon in Mines and Homes -- Copyright -- Preface -- CHARGE TO THE COMMITTEE -- ORGANIZATION OF THE STUDY -- ORGANIZATION OF THE REPORT -- ACKNOWLEDGMENTS -- Contents -- Summary and Recommendations -- RECOMMENDATIONS FOR FURTHER RESEARCH AND ANALYSIS -- REFERENCES -- 1 Introduction -- CONCENTRATION, EXPOSURE, AND DOSE -- RISK ASSESSMENT FOR INDOOR RADON -- SUMMARY -- REFERENCES -- 2 Assessment of Exposure to the Decay Products of 222Rn in Mines and Homes -- INTRODUCTION -- BACKGROUND -- MEASUREMENT METHODS -- EXPOSURE TO RADON PROGENY -- Mine Atmospheres -- Indoor Atmospheres -- REFERENCES -- 3 Extrapolation of Doses and Risk per Unit Exposure from Mines to Homes -- INTRODUCTION -- REPRESENTATIVE EXPOSURE CONDITIONS -- Radon Progeny Aerosols -- BREATHING RATES AND CALCULATION OF DOSE PER UNIT EXPOSURE -- COMPARATIVE DOSES FROM RADON PROGENY IN MINES AND HOMES -- Target Cells in Bronchial Epithelium -- LOCALIZED VERSUS REGIONAL DOSES -- INFLUENCE OF MODELING UNCERTAINTIES -- DOSES TO ADULT FEMALES -- DOSES TO CHILDREN AND INFANTS -- VARIABILITY OF THE DOSE CONVERSION COEFFICIENT IN HOMES -- EFFECTS OF AIRWAY DISEASE ON DOSE -- COMPARATIVE DOSES FROM RADON AND THORON PROGENY -- SUMMARY OF DOSIMETRIC RISK EXTRAPOLATION FACTORS -- REFERENCES -- 4 Other Considerations -- BIOLOGICAL FACTORS -- GENDER -- AGE, GROWTH, AND INJURY IN RELATION TO CELL PROLIFERATION -- AGE -- CELL PROLIFERATION -- DOSE RATE, FRACTIONATION, AND DURATION OF EXPOSURE -- TISSUE DAMAGE -- CIGARETTE SMOKING -- REFERENCES -- 5 Dosimetry and Dosimetric Models for Inhaled Radon and Progeny -- SOME PHYSICAL CHARACTERISTICS OF RADON AND RADON PROGENY -- MORPHOMETRIC MODELS OF THE RESPIRATORY TRACT -- HEAD AIRWAY MORPHOMETRY -- TRACHEOBRONCHIAL AIRWAY MORPHOMETRY -- RESPIRATORY AIRWAY MORPHOMETRY -- DEPOSITION MODELS OF THE RESPIRATORY TRACT.