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Sample records for biological dosimetry study

  1. Neutron dosimetry in biology

    International Nuclear Information System (INIS)

    Sigurbjoernsson, B.; Smith, H.H.; Gustafsson, A.

    1965-01-01

    To study adequately the biological effects of different energy neutrons it is necessary to have high-intensity sources which are not contaminated by other radiations, the most serious of which are gamma rays. An effective dosimetry must provide an accurate measure of the absorbed dose, in biological materials, of each type of radiation at any reactor facility involved in radiobiological research. A standardized biological dosimetry, in addition to physical and chemical methods, may be desirable. The ideal data needed to achieve a fully documented dosimetry has been compiled by H. Glubrecht: (1) Energy spectrum and intensity of neutrons; (2) Angular distribution of neutrons on the whole surface of the irradiated object; (3) Additional undesired radiation accompanying the neutrons; (4) Physical state and chemical composition of the irradiated object. It is not sufficient to note only an integral dose value (e.g. in 'rad') as the biological effect depends on the above data

  2. Biological dosimetry of X-rays by micronuclei study

    International Nuclear Information System (INIS)

    Gomez, E.; Silva, A.; Navlet, J.

    1991-01-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in hematological, biochemical an cytogenetics data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable, in this case, the study of micronuclei in peripheral blood lymphocytes cytokinetic blocked can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using micronuclei assay for X-rays at 250 kVp, 43,79 rads/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y=c+ α D+β D 2 where. Y is the number micronuclei per cell and D the dose. the curve is compared with those produced elsewhere

  3. Biological Dosimetry of X-rays by micronuclei study

    International Nuclear Information System (INIS)

    Gomez, E.; Silva, A.; Navlet, J.

    1991-01-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical an cytogenetics data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable, in this case, the study of micronuclei in peripheral blood lymphocytes citokinetics blocked can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using micronuclei assay for X-rays at 250 kVp, 43,79 rads/min and temperature 37 degree centigree has been produced. Experimental data is fitted to model Y=C+ αD+BD''2 where Y is the number of micronuclei per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 24 refs

  4. Study on biological dosimetry of premature chromosome condensation technique

    International Nuclear Information System (INIS)

    Jiang Bo

    2005-01-01

    The premature chromosome condensation technique has been applied for biological dosimetry purpose. Premature chromo-some condensation was induced by incubating unstimulated human peripheral blood lymphocytes in the presence of okadaic acid or calyculin A (a phosphatase inhibitor) which eliminated the need for fusion with mitotic cells. It is now possible to examine the early damage induced by radiation. It is simple, exact when it combines with fluorecence in situ hybridization. (authors)

  5. Biological dosimetry studies for boron neutron capture therapy at the RA-1 research reactor facility

    International Nuclear Information System (INIS)

    Trivillin, Veronica A.; Heber, Elisa M.; Itoiz, Maria E.; Schwint, Amanda E.; Castillo, Jorge

    2004-01-01

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminescent dosimeters to characterize the BNCT facility developed at the RA-1 research reactor operated by the National Atomic Energy Commission in Buenos Aires. Biological dosimetry was performed employing the hamster cheek pouch oral cancer model previously validated for BNCT studies by our group. Results indicate that the RA-1 neutron source produces useful dose rates for BNCT studies but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications. (author)

  6. Biological dosimetry study in differentiated thyroid carcinoma patients treated with 131Iodine

    International Nuclear Information System (INIS)

    Vallerga, Maria Belen

    2008-11-01

    Biological Dosimetry allows individual dose assessments based on the effect produced by ionizing radiation on a given biological parameter. The current biological endpoint being scored is chromosomal aberrations, relying on a lymphocytes culture from the patient's blood. The measured yield of chromosome aberrations is referred to a calibration curve obtaining the whole body dose. Different scenarios of overexposure can be taken into account by modifying the calculations leading to the dose estimate. Differentiated Thyroid Carcinoma patients undergo thyroidectomy followed by internal radiotherapy with 131 I. The treatment's success entails the delivery of a lethal dose to the tumour within the maximum tolerable dose to a critical organ (blood doses over 2 Gy could lead to bone marrow depression). Currently, there is no established agreement for the selection of radioiodine dosage. Historically, the empiric approach, based on clinical and biochemical data, has been recommended. Nevertheless, this method may not be associated with optimal outcomes. On the other hand, the dosimetric approach attempts to determine the maximum allowable activity to be administered, establishing its biokinetics by a diagnostic 131 I study. The methodology may be modified to further individualized treatment, however it requires validation. Biological dosimetry provides an independent measure of radiotherapy effect, as such it might aid in the validation process. Nonetheless, biological dosimetry has traditionally been applied in cases of external and accidental overexposure to ionizing radiation. Accordingly, it is mandatory to assess its value in medical internal incorporations (main objective of the present study). The applied treatment strategy comprises whole body dose assessment by biological and internal dosimetry in order to administer a personalized therapeutic activity. Overall, 20 patients with differentiated thyroid carcinoma were included in the study. For biological dosimetry

  7. Metabolomics in Radiation-Induced Biological Dosimetry: A Mini-Review and a Polyamine Study

    Directory of Open Access Journals (Sweden)

    Changhyun Roh

    2018-05-01

    Full Text Available In this study, we elucidate that polyamine metabolite is a powerful biomarker to study post-radiation changes. Metabolomics in radiation biodosimetry, the application of a metabolomics analysis to the field of radiobiology, promises to increase the understanding of biological responses by ionizing radiation (IR. Radiation exposure triggers a complex network of molecular and cellular responses that impacts metabolic processes and alters the levels of metabolites. Such metabolites have potential as biomarkers for radiation dosimetry. Among metabolites, polyamine is one of many potential biomarkers to estimate radiation response. In addition, this review provides an opportunity for the understanding of a radiation metabolomics in biodosimetry and a polyamine case study.

  8. Biological dosimetry of irradiation accidents

    International Nuclear Information System (INIS)

    Durand, V.; Chambrette, V.; Le Roy, A.; Paillole, N.; Sorokine, I.; Voisin, P.

    1994-01-01

    The biological dosimetry in radiation protection allows to evaluate the received dose by a potentially irradiated person from biological markers such chromosomal abnormalities. The technologies of Hybridization In Situ by Fluorescence (F.I.S.H) allow the detection of steady chromosomal aberrations of translocation type

  9. The Latin American Biological Dosimetry Network (LBDNet)

    International Nuclear Information System (INIS)

    Garcia, O.; Lamadrid, A.I.; Gonzalez, J.E.; Romero, I.; Mandina, T.; Di Giorgio, M.; Radl, A.; Taja, M.R.; Sapienza, C.E.; Deminge, M.M.; Fernandez Rearte, J.; Stuck Oliveira, M.; Valdivia, P.; Guerrero-Carbajal, C.; Arceo Maldonado, C.; Cortina Ramirez, G.E.; Espinoza, M.; Martinez-Lopez, W.; Di Tomasso, M.

    2016-01-01

    Biological Dosimetry is a necessary support for national radiation protection programmes and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 to provide early biological dosimetry assistance in case of radiation emergencies in the Latin American Region. Here are presented the main topics considered in the foundational document of the network, which comprise: mission, partners, concept of operation, including the mechanism to request support for biological dosimetry assistance in the region, and the network capabilities. The process for network activation and the role of the coordinating laboratory during biological dosimetry emergency response is also presented. This information is preceded by historical remarks on biological dosimetry cooperation in Latin America. A summary of the main experimental and practical results already obtained by the LBDNet is also included. (authors)

  10. The Latin American Biological Dosimetry Network (LBDNet).

    Science.gov (United States)

    García, O; Di Giorgio, M; Radl, A; Taja, M R; Sapienza, C E; Deminge, M M; Fernández Rearte, J; Stuck Oliveira, M; Valdivia, P; Lamadrid, A I; González, J E; Romero, I; Mandina, T; Guerrero-Carbajal, C; ArceoMaldonado, C; Cortina Ramírez, G E; Espinoza, M; Martínez-López, W; Di Tomasso, M

    2016-09-01

    Biological Dosimetry is a necessary support for national radiation protection programmes and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 to provide early biological dosimetry assistance in case of radiation emergencies in the Latin American Region. Here are presented the main topics considered in the foundational document of the network, which comprise: mission, partners, concept of operation, including the mechanism to request support for biological dosimetry assistance in the region, and the network capabilities. The process for network activation and the role of the coordinating laboratory during biological dosimetry emergency response is also presented. This information is preceded by historical remarks on biological dosimetry cooperation in Latin America. A summary of the main experimental and practical results already obtained by the LBDNet is also included. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. A contribution to the study of the biological dosimetry in clinical radiopathology

    International Nuclear Information System (INIS)

    Eston, T.E. de.

    1983-01-01

    The effects of total body irradiation with different radiation doses from a 4MeV linear accelerator on organs and tissues of adult male rabbits were studied. Doses of 0.50, 2.00, 6.00 and 8.00 Gy were applied. Different organic parameters were evaluated before and after various periods of the post-irradiation time. Mortality did not occured for 0.50 or 2.00 Gy, but morbility was greater in comparison with the control; sexual potency was maintained. 'Impotentia colundi' occured with 6 Gy. A small loss of weight occured with 2.00 Gy and a higher loss for 6.00 Gy, with later recovery. Blood parameters varied even for lowest dose. Alterations were evident in the bone marrow activity for 2.00 and 6.00 Gy. Spermatides, spermatocytes and mature spermatozoids were affect even by low doses, the laters loosing motility. Significant difference was observed in the relation DNA/RNA for irradiated-and control animals. The results showed that T3 asssay could serve as 'biological indicator' of irradiation in a period of at least 7 hours and for doses of 4Gy or more. Using the kinetic method, an increase of glutamic oxalacetic transaminase (GOT) seric levels was observed for 6.00 Gy after 7 hours and a decrease for the glutamic pyruvic transaminase (GPT). Fasting glycemy and catecolamines urinary extraction were not statiscally significants. The study of chromosomal aberrations that occur in lymphocytes after 'in vitro' irradiation showed that this is at the present moment the most efficient method for biological dosimetry. (M.A.) [pt

  12. Development of technology for biological dosimetry -A study on the radiation and environmental safety-

    International Nuclear Information System (INIS)

    Lee, Kang Suk; Cheon, Ki Jeong; Kim, Kook Chan; Kim, Jin Kyu; Kim, Sang Bok; Kim, In Kyu; Park, Hyo Kook

    1994-07-01

    α-amylase showed a significant increase in its activity when exposed to radiation of 0.1 Gy. However it had no relationship with radiation dose. Enzyme activities in liver tissue showed similar changes to those in serum. Among others, changes in acid phosphatase activity were highly related to radiation dose. Of acute phase proteins in serum, CRP, ceruloplasmin and haptoglobin positively responded to radiation while albumin did negatively. ELISA proved to be an efficient method to detect changes in serum protein level. Finally the measurements of changes in APRs using ELISA could provide an useful tools for biological dosimetry. (Author)

  13. Studies with encapsulated 125I sources: dosimetry for determination of relative biological effectiveness

    International Nuclear Information System (INIS)

    Goldhagen, P.; Freeman, M.L.; Hall, E.J.

    1981-01-01

    During the past year, members of this laboratory have measured the Relative Biological Effectiveness (RBE) of photons from encapsulated 125 I sources (mean energy = 28.33 keV) using 661.6 keV 137 Cs gamma rays as a standard for comparison. These experiments were performed at clinically relevant dose rates and used reduction of the reproductive viability of mammalian cells as an endpoint. This section will discuss how dosimetry problems special to 125 I influence the design of the apparatus and will describe the ionization chamber to be used for measuring dose rates from both 125 I and 137 Cs photons

  14. Calibration curves for biological dosimetry

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M. . E-mail cgc@nuclear.inin.mx

    2004-01-01

    The generated information by the investigations in different laboratories of the world, included the ININ, in which settles down that certain class of chromosomal leisure it increases in function of the dose and radiation type, has given by result the obtaining of calibrated curves that are applied in the well-known technique as biological dosimetry. In this work is presented a summary of the work made in the laboratory that includes the calibrated curves for gamma radiation of 60 Cobalt and X rays of 250 k Vp, examples of presumed exposure to ionizing radiation, resolved by means of aberration analysis and the corresponding dose estimate through the equations of the respective curves and finally a comparison among the dose calculations in those people affected by the accident of Ciudad Juarez, carried out by the group of Oak Ridge, USA and those obtained in this laboratory. (Author)

  15. Development of radiation biological dosimetry

    International Nuclear Information System (INIS)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil; Son, Young Sook; Kim, Soo Kwan; Jang, Won Suk; Le, Sun Joo; Jee, Young Heun; Jung, Woo Jung

    1999-04-01

    Up until now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline (triage) to be able to be treated the victims as fast as possible. We established the premature chromosome condensation assay and apoptotic fragment assay which was the significant relationship between dose and cell damages to evaluate the irradiation dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with conventional chromosome aberration assay and micronuclei assay

  16. Development of radiation biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil; Son, Young Sook; Kim, Soo Kwan; Jang, Won Suk; Le, Sun Joo; Jee, Young Heun; Jung, Woo Jung

    1999-04-01

    Up until now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline (triage) to be able to be treated the victims as fast as possible. We established the premature chromosome condensation assay and apoptotic fragment assay which was the significant relationship between dose and cell damages to evaluate the irradiation dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with conventional chromosome aberration assay and micronuclei assay.

  17. Cytogenetic biological dosimetry. Dose estimative in accidental exposure

    International Nuclear Information System (INIS)

    Santos, O.R. dos; Campos, I.M.A. de.

    1988-01-01

    The methodology of cytogenetic biological dosimetry is studied. The application in estimation of dose in five cases of accidental exposure is reported. An hematological study and culture of lymphocytes is presented. (M.A.C.) [pt

  18. Dosimetry and biological effects of fast neutrons

    International Nuclear Information System (INIS)

    Zoetelief, J.

    1981-01-01

    This thesis contains studies on two types of cellular damage: cell reproductive death and chromosome aberrations induced by irradiation with X rays, gamma rays and fast neutrons of different energies. A prerequisite for the performance of radiobiological experiments is the determination of the absorbed dose with a sufficient degree of accuracy and precision. Basic concepts of energy deposition by ionizing radiation and practical aspects of neutron dosimetry for biomedical purposes are discussed. Information on the relative neutron sensitivity of GM counters and on the effective point of measurement of ionization chambers for dosimetry of neutron and photon beams under free-in-air conditions and inside phantoms which are used to simulate the biological objects is presented. Different methods for neutron dosimetry are compared and the experimental techniques used for the investigations of cell reproductive death and chromosome aberrations induced by ionizing radiation of different qualities are presented. Dose-effect relations for induction cell inactivation and chromsome aberrations in three cultured cell lines for different radiation qualities are presented. (Auth.)

  19. Preliminary study on biological dosimetry using alkaline single cell gel electrophoresis of human peripheral lymphocytes

    International Nuclear Information System (INIS)

    Liu Qingjie; Lu Xue; Feng Jiangbing; Chen Deqing; Chen Xiaosui

    2006-01-01

    Objective: To explore the feasibility of alkaline single cell gel electrophoresis (SCGE) in biological dosimetry of ionizing radiation. Methods: Normal peripheral blood samples from two healthy males were exposed to different doses coblat-60 gamma-rays, ranged from 0 to 5 Gy, and the tail length (TL) and Oliver tail moment (TM) of the lymphocytes were analyzed with SCGE. The dose-effect curves of TL and TM were fitted respectively. The TL and TM of lymphocytes for eight radiation workers were analyzed with SCGE, cumulative doses were estimated using the fitted TL and TM equations, and then compared with the recorded monitoring doses. Results: The TLs or TMs of normal human lymphocytes were increased with the irradiation doses, and its relationship can be fitted with a linear-quadratic equations: Y=13.59 + 20.87X - 2.27 X 2 for TL, and Y = 8.50 + 15.04X - 1.43X 2 for TM, respectively (Y denotes TL or TM value, X is radiation dose). The doses estimated with TM equation were closer to the recorded monitoring doses than that with TL equation. Conclusions: The TM in lymphocytes analyzed with SCGE is a promising radiation biological dosimeter. (authors)

  20. Biological Dosimetry of X-rays by micronuclei study; Dosimetria Biologica de rayos-X mediante el estudio de micronucleos

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, E.; Silva, A.; Navlet, J.

    1991-07-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical an cytogenetics data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable, in this case, the study of micronuclei in peripheral blood lymphocytes citokinetics blocked can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using micronuclei assay for X-rays at 250 kVp, 43,79 rads/min and temperature 37 degree centigree has been produced. Experimental data is fitted to model Y=C+ {alpha}D+BD''2 where Y is the number of micronuclei per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 24 refs.

  1. Biological Dosimetry of X-rays by micronuclei study; Dosimetria Biologica de rayos-X mediante el estudio de micronucleos

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, E; Silva, A; Navlet, J

    1991-07-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical an cytogenetics data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable, in this case, the study of micronuclei in peripheral blood lymphocytes citokinetics blocked can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using micronuclei assay for X-rays at 250 kVp, 43,79 rads/min and temperature 37 degree centigree has been produced. Experimental data is fitted to model Y=C+ {alpha}D+BD''2 where Y is the number of micronuclei per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 24 refs.

  2. Establishing working standards of chromosome aberrations analysis for biological dosimetry

    International Nuclear Information System (INIS)

    Bui Thi Kim Luyen; Tran Que; Pham Ngoc Duy; Nguyen Thi Kim Anh; Ha Thi Ngoc Lien

    2015-01-01

    Biological dosimetry is an dose assessment method using specify bio markers of radiation. IAEA (International Atomic Energy Agency) and ISO (International Organization for Standardization) defined that dicentric chromosome is specify for radiation, it is a gold standard for biodosimetry. Along with the documents published by IAEA, WHO, ISO and OECD, our results of study on the chromosome aberrations induced by radiation were organized systematically in nine standards that dealing with chromosome aberration test and micronucleus test in human peripheral blood lymphocytes in vitro. This standard addresses: the reference dose-effect for dose estimation, the minimum detection levels, cell culture, slide preparation, scoring procedure for chromosome aberrations use for biodosimetry, the criteria for converting aberration frequency into absorbed dose, reporting of results. Following these standards, the automatic analysis devices were calibrated for improving biological dosimetry method. This standard will be used to acquire and maintain accreditation of the Biological Dosimetry laboratory in Nuclear Research Institute. (author)

  3. Biological dosimetry, scopes and limitations

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M.

    1999-01-01

    The analysis of the aberrations in chromosomes is an alternative to establish the exposure dose to the radiation, when the information provided by the traditional physical methods is insufficient. There are diverse causes by which it can reached to apply an alternative system, such is the case of exposures of another persons to the management of radiation sources, which not carry physical dosemeter. Contrary case is to the occupational exposure personnel (OEP), what must to utilize some system for determining the exposure dose, even so can be needed the case for more information. In any case, the cells from the affected person are the alternative without the biological system be overlap to the physical, it is complementary. (Author)

  4. DRDC Ottawa working standard for biological dosimetry

    International Nuclear Information System (INIS)

    Segura, T.M.; Prud'homme-Lalonde, L.; Thorleifson, E.; Lachapelle, S.; Mullins, D.; Qutob, S.; Wilkinson, D.

    2005-07-01

    This Standard provides quality assurance, quality control, and evaluation of the performance criteria for the purpose of accreditation of the Radiation Biology laboratory at Defence Research and Development Canada - Ottawa (DRDC Ottawa) using biological dosimetry to predict radiation exposure doses. The International Standard (ISO 19238) and the International Atomic Energy Association (IAEA) Technical Report Series No. 405 are used as guiding documents in preparation of this working document specific to the DRDC Ottawa Radiation Biology Laboratory. This Standard addresses: 1. The confidentiality of personal information, for the customer and the service laboratory; 2. The laboratory safety requirements; 3. The calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels; 4. Transportation criteria for shipping of test samples to the laboratory; 5. Preparation of samples for analysis; 6. The scoring procedure for unstable chromosome aberrations used for biological dosimetry; 7. The criteria for converting a measured aberration frequency into an estimate of absorbed dose; 8. The reporting of results; 9. The quality assurance and quality control plan for the laboratory; and 10. Informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations, a sample report and other supportive documents. (author)

  5. DRDC Ottawa working standard for biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Segura, T M; Prud' homme-Lalonde, L [Defence Research and Development Canada, Ottawa, Ontario (Canada); Thorleifson, E [Health Canada, Gatineau, Quebec (Canada); Lachapelle, S; Mullins, D [JERA Consulting (Canada); Qutob, S [Health Canada, Gatineau, Quebec (Canada); Wilkinson, D

    2005-07-15

    This Standard provides quality assurance, quality control, and evaluation of the performance criteria for the purpose of accreditation of the Radiation Biology laboratory at Defence Research and Development Canada - Ottawa (DRDC Ottawa) using biological dosimetry to predict radiation exposure doses. The International Standard (ISO 19238) and the International Atomic Energy Association (IAEA) Technical Report Series No. 405 are used as guiding documents in preparation of this working document specific to the DRDC Ottawa Radiation Biology Laboratory. This Standard addresses: 1. The confidentiality of personal information, for the customer and the service laboratory; 2. The laboratory safety requirements; 3. The calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels; 4. Transportation criteria for shipping of test samples to the laboratory; 5. Preparation of samples for analysis; 6. The scoring procedure for unstable chromosome aberrations used for biological dosimetry; 7. The criteria for converting a measured aberration frequency into an estimate of absorbed dose; 8. The reporting of results; 9. The quality assurance and quality control plan for the laboratory; and 10. Informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations, a sample report and other supportive documents. (author)

  6. Collaborative Physical and Biological Dosimetry Studies for Neutron Capture Therapy at the RA-1 Research Reactor Facility

    Energy Technology Data Exchange (ETDEWEB)

    David W. Nigg; Amanda E. Schwint; John K. Hartwell; Elisa M. Heber; Veronica Trivillin; Jorge Castillo; Luis Wentzeis; Patrick Sloan; Charles A. Wemple

    2004-10-01

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.

  7. Collaborative Physical and Biological Dosimetry Studies for Neutron Capture Therapy at the RA-1 Research Reactor Facility

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D.W.; Schwint, A.E.; Hartwell, J.K.; Heber, E.M.; Trivillin, V.; Castillo, J.; Wentzeis, L.; Sloan, P.; Wemple, C.A.

    2004-10-04

    Initial physical dosimetry measurements have been completed using activation spectrometry and thermoluminiscent dosimeters to characterize the BNCT irradiation facility developed at the RA-1 research reactor operated by the Argentine National Atomic Energy Commission in Buenos Aires. Some biological scoping irradiations have also been completed using a small-animal (hamster) oral mucosa tumor model. Results indicate that the RA-1 neutron source produces useful dose rates but that some improvements in the initial configuration will be needed to optimize the spectrum for thermal-neutron BNCT research applications.

  8. Reproductive function and biological dosimetry prospective study of young thyroid differentiated cancer patients treated with I-131

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Taja, Maria R.; Radl, Analia; Chebel, Graciela; Fadel, Ana M.; Gutierrez, Silvia; Normandi, Eduardo; Levalle, Oscar; Kundt, Miriam

    2008-01-01

    Full text: The administration of I-131 in the management of differentiated thyroid cancer (DTC) is a well established practice. As the spermatogonia is highly sensitive to radiation, large doses of internal radiation could result in adverse effects on reproductive function such as oligo/azoospermia and infertility. During spermiogenesis, mammalian chromatin undergoes replacement of nuclear histones by protamines, which yields a DNA sixfold more highly condensed in spermatozoa than in mitotic chromosomes. The structure of this highly packaged chromatin shows a low binding capacity for several fluoro chromes and dyes such as chromo mycin A 3 (CMA 3 ). The aim of this study is to assess the correlation between reproductive function (endocrine and exocrine testicular function, and levels of CMA 3 stainability) and biological dosimetry in a prospective study of 4 young DTC patients treated with I-131. In this context, a background level of CMA 3 binding in mature human sperm was established. It revealed a variable accessibility of CMA 3 to the DNA that is dependant on packaging quality and thus, indicative of protamine deficiency. The identification of altered stainability suggests DNA damage as well as epigenetic effects, which may be indicators of male infertility. Transient impairment of spermatogenesis associated with an increase in FSH, an altered spermiogram and even azoospermia was observed after the administration of cumulative activities. Overall, testosterone levels were preserved, except in one case, which presented a drastically diminished value associated with an increase in LH level. As peripheral blood lymphocytes and spermatogonia have equivalent radiosensitivity (interphase death) we hypothesize that the knowledge of DNA damage recovery in peripheral lymphocytes could correlate with spermatogonia recovery and with FSH evolution. Therefore, a prospective study on the decline of unstable chromosome aberrations is being conducted, considering the damage

  9. Reproductive function and biological dosimetry prospective study of young thyroid differentiated cancer patients treated with I-131

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Taja, M.R.; Radl, A.; Chebel, Graciela; Fadel, Ana Maria; Gutierrez, Silvia; Normandi, Eduardo; Levalle, Oscar; Kundt, Miriam

    2011-01-01

    The administration of I-131 in the management of differentiated thyroid cancer (DTC) is a well established practice. As the spermatogonia is highly sensitive to radiation, large doses of internal radiation could result in adverse effects on reproductive function such as oligo/azoospermia and infertility. During spermiogenesis, mammalian chromatin undergoes replacement of nuclear histones by protamines, which yields a DNA sixfold more highly condensed in spermatozoa than in mitotic chromosomes. The structure of this highly packaged chromatin shows a low binding capacity for several fluorochromes and dyes such as chromomycin A3 (CMA3). The aim of this study is to assess the correlation between reproductive function (endocrine and exocrine testicular function, and levels of CMA3 stainability) and biological dosimetry in a prospective study of 4 young DTC patients treated with I-131. In this context, a background level of CMA3 binding in mature human sperm was established. It revealed a variable accessibility of CMA3 to the DNA that is dependant on packaging quality and thus, indicative of protamine deficiency. The identification of altered stainability suggests DNA damage as well as epigenetic effects, which may be indicators of male infertility. Transient impairment of spermatogenesis associated with an increase in FSH, an altered spermiogram and even azoospermia was observed after the administration of cumulative activities. Overall, testosterone levels were preserved, except in one case, which presented a drastically diminished value associated with an increase in LH level. As peripheral blood lymphocytes and spermatogonia have equivalent radiosensitivity (interphase death) we hypothesize that the knowledge of DNA damage recovery in peripheral lymphocytes could correlate with spermatogonia recovery and with FSH evolution. (authors)

  10. About the factors distorting biological dosimetry results

    International Nuclear Information System (INIS)

    Mosseh, I.B.

    1999-01-01

    The row of chemical substances that have not mutagenic effect can strengthen ionising radiation induced cytogenetic effects. For example nitrite sodium and nitrate sodium reinforce mutagenic action of radiation and cause sensitized effect although they aren't mutagens. Presence of residual amount of herbicides in food products can have influence at level of aberration in human cells. It was investigated the influence of herbicide zencor at mutagenic action of radiation. This substance has weak mutagenic activity. In the case of combined action of zencor with irradiation antagonistic effect was observed. Mutation rate turns out to be lower than expected summary value. At the same time many foods products (tea, coffee, cacao, chocolate etc., which contain melanin) are antimutagens and can also change the frequency of radiation induced mutations. Taking of medicine distort the results of dose estimation. The frequency of chromosomal aberrations in blood lymphocytes after acute irradiation is considered to be adequate method of biological dosimetry. In the case of chronic irradiation this analysis becomes complicated with such processes as adaptation (selection and proliferation of cells with more radioresistant genotype) and the origin of genetic un stability which leads to higher radiosensitivity. The estimation of the level of point mutations is the most precise method of biological dosimetry because their existence is less exposed to modifications

  11. Dosimetry

    International Nuclear Information System (INIS)

    Rezende, D.A.O. de

    1976-01-01

    The fundamental units of dosimetry are defined, such as exposure rate, absorbed dose and equivalent dose. A table is given of relative biological effectiveness values for the different types of radiation. The relation between the roentgen and rad units is calculated and the concepts of physical half-life, biological half-life and effective half-life are discussed. Referring to internal dosimetry, a mathematical treatment is given to β particle-and γ radiation dosimetry. The absorbed dose is calculated and a practical example is given of the calculation of the exposure and of the dose rate for a gama source [pt

  12. The status of the seventh report in the series Biological Effects of Ionizing Radiations and a revised dosimetry for the Radiation Effects Research Foundation's A-bomb studies

    International Nuclear Information System (INIS)

    Douple, Evan; Jostes, Rick

    2002-01-01

    Results of a National Academies workshop and feasibility study led US Governmental agencies to request the Board on Radiation Effects Research of the National Research Council to commence a risk assessment study in 1998 as the seventh report in the series Biological Effects of Ionizing Radiations (BEIR VII). Originally targeted for completion in the autumn of 2001, the study Potential Health Effects of Exposure to Low Dose, Low-LET Ionizing Radiation was extended until the autumn of 2003 at the request of the sponsors. Two factors contributing to this decision are discussed: a revised dosimetry to update DS86 for the Radiation Effects Research Foundation's A-bomb-survivor studies and the potential for new information to become available from low-dose studies that are under way. Epidemiological and biological data since BEIR V are being considered by a BEIR VII committee composed of 17 members. The committee's statement of task is reviewed along with the major recommendations of the recent National Research Council report on the status of DS86 - recommendations that are being implemented by US and Japan dosimetry working groups. (author)

  13. Dosimetry

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The purpose of ionizing radiation dosimetry is the measurement of the physical and biological consequences of exposure to radiation. As these consequences are proportional to the local absorption of energy, the dosimetry of ionizing radiation is based on the measurement of this quantity. Owing to the size of the effects of ionizing radiation on materials in all of these area, dosimetry plays an essential role in the prevention and the control of radiation exposure. Its use is of great importance in two areas in particular where the employment of ionizing radiation relates to human health: radiation protection, and medical applications. Dosimetry is different for various reasons: owing to the diversity of the physical characteristics produced by different kinds of radiation according to their nature (X- and γ-photons, electrons, neutrons,...), their energy (from several keV to several MeV), the orders of magnitude of the doses being estimated (a factor of about 10 5 between diagnostic and therapeutic applications); and the temporal and spatial variation of the biological parameters entering into the calculations. On the practical level, dosimetry poses two distinct yet closely related problems: the determination of the absorbed dose received by a subject exposed to radiation from a source external to his body (external dosimetry); and the determination of the absorbed dose received by a subject owing to the presence within his body of some radioactive substance (internal dosimetry)

  14. Latinamerican Biological Dosimetry Network (LBDNET). International Biological Dosimetry intercomparison Program (exercise 2007-2008)

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Radl, A.; Taja, Maria R.

    2009-01-01

    This paper describes the International Biological Dosimetry Intercomparison Program (exercise 2007-2008) - developed within the framework of the IAEA regional project - RLA/9/054 (Establishment of national capabilities for response to radiological and nuclear emergency) whose general objectives are: assess reproducibility inter-laboratory; identify problems and provide the necessary modifications for collaborative work in accidental situations requiring activation of mutual assistance mechanisms which will form the basis of the Organization of LBDNET. This exercise involves the laboratories of the region: Argentina (laboratory support), Brazil, Chile, Cuba, Mexico, Peru and Uruguay and the laboratory of the Autonomous University of Barcelona-Espana (Joan Francesc Barquinero and staff). Finally, these countries will meet the next time for the drafting of a final report and later publication. (author)

  15. Biological dosimetry of ionizing radiation by chromosomal aberration analysis

    International Nuclear Information System (INIS)

    Gonzalez-Castano, S.; Silva, A.; Navlet, J.

    1990-01-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study ol chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y =α + β 1 D + β 2 D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 14 refs

  16. Biological dosimetry of ionizing radiation by chromosomal aberration analysis

    International Nuclear Information System (INIS)

    Navlet Armenta, J.M.; Gonzalez, S.; Silva, A.

    1990-01-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haemathological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study of chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 o C has been produced. Experimental data is fitted to model Y = α+β 1 D+β 2 D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author)

  17. New methodologies of biological dosimetry applied to human protection

    International Nuclear Information System (INIS)

    Catena, C.; Parasacchi, P.; Conti, D.; Righi, E.

    1995-04-01

    Biological dosimetry is a diagnostic methodology for the measurement of the individual dose absorbed in the case of accidental overexposition to ionizing radiation. It is demonstrated how in vitro radiobiological and chemobiological studies using cytogenetic methods (count of chromosomal aberrations and micronuclei) on human lymphocytes from healthy subjects and individuals undergoing radiotherapy or chemotherapy, as well as on lymphocytes of mammals other than man (comparative cytogenetics), can help to increase the basic radiobiological and chemobiological scientific information. Such information gives a valid contribution to understanding of the action of ionizing radiation or of pharmaceuticals on cells and, in return, can be of value to human radioprotection and chemoprotection. Cytogenetic studies can be summerized as follows: a) biodosimetry (estimate of dose received after accidental events); b) individual radiosensitivity (level of individual response); c) clinical radiobiology and chemobiology (individual response to radiopharmaceuticals, to radiotherapy and to chemopharmaceuticals); d) comparative radiobiology (cytogenetic studies on species other than man); e) animal model in the environmental surveillance

  18. AN EXACT GOODNESS-OF-FIT TEST BASED ON THE OCCUPANCY PROBLEMS TO STUDY ZERO-INFLATION AND ZERO-DEFLATION IN BIOLOGICAL DOSIMETRY DATA.

    Science.gov (United States)

    Fernández-Fontelo, Amanda; Puig, Pedro; Ainsbury, Elizabeth A; Higueras, Manuel

    2018-01-12

    The goal in biological dosimetry is to estimate the dose of radiation that a suspected irradiated individual has received. For that, the analysis of aberrations (most commonly dicentric chromosome aberrations) in scored cells is performed and dose response calibration curves are built. In whole body irradiation (WBI) with X- and gamma-rays, the number of aberrations in samples is properly described by the Poisson distribution, although in partial body irradiation (PBI) the excess of zeros provided by the non-irradiated cells leads, for instance, to the Zero-Inflated Poisson distribution. Different methods are used to analyse the dosimetry data taking into account the distribution of the sample. In order to test the Poisson distribution against the Zero-Inflated Poisson distribution, several asymptotic and exact methods have been proposed which are focused on the dispersion of the data. In this work, we suggest an exact test for the Poisson distribution focused on the zero-inflation of the data developed by Rao and Chakravarti (Some small sample tests of significance for a Poisson distribution. Biometrics 1956; 12 : 264-82.), derived from the problems of occupancy. An approximation based on the standard Normal distribution is proposed in those cases where the computation of the exact test can be tedious. A Monte Carlo Simulation study was performed in order to estimate empirical confidence levels and powers of the exact test and other tests proposed in the literature. Different examples of applications based on in vitro data and also data recorded in several radiation accidents are presented and discussed. A Shiny application which computes the exact test and other interesting goodness-of-fit tests for the Poisson distribution is presented in order to provide them to all interested researchers. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Neutron generator (HIRRAC) and dosimetry study.

    Science.gov (United States)

    Endo, S; Hoshi, M; Takada, J; Tauchi, H; Matsuura, S; Takeoka, S; Kitagawa, K; Suga, S; Komatsu, K

    1999-12-01

    Dosimetry studies have been made for neutrons from a neutron generator at Hiroshima University (HIRRAC) which is designed for radiobiological research. Neutrons in an energy range from 0.07 to 2.7 MeV are available for biological irradiations. The produced neutron energies were measured and evaluated by a 3He-gas proportional counter. Energy spread was made certain to be small enough for radiobiological studies. Dose evaluations were performed by two different methods, namely use of tissue equivalent paired ionization chambers and activation of method with indium foils. Moreover, energy deposition spectra in small targets of tissue equivalent materials, so-called lineal energy spectrum, were also measured and are discussed. Specifications for biological irradiation are presented in terms of monoenergetic beam conditions, dose rates and deposited energy spectra.

  20. Direct biological dosimetry in Chernobyl clear-up workers

    International Nuclear Information System (INIS)

    Maznik, N.A.; Vinnikov, V.A.; Rozdil'ski, S.I.

    1999-01-01

    Full text: In cases of large-scale radiological accidents like Chernobyl (1986) the estimation of somatic risk to exposed populations became a problem due to lack of direct physical dosimetry data. In such conditions the necessarily information can be obtained from biological dosimetry, firstly by chromosomal aberrations analysis in human peripheral blood lymphocytes. Conventional cytogenetic assay have been carried out in 130 persons recruited as clean-up workers ('liquidators') to the Chernobyl zone in 1986-87 yrs. Blood sampling was performed during 1 year post-irradiation, in 100 persons p to 0.5 year. The aberrations of choice for biological dosimetry were unstable chromosome exchanges (dicentrics and centric rings with accompanying acentric fragments). The dose calculations have been done using the linear term of the dose-response curve built with acute gamma-irradiation of blood in dose range up to 1 Gy. The distributions of biological doses were investigated in groups of liquidators with doses in documents ranging 17-140, 175-230, 250, 260-365, 440-1030 mSv and in the group of non-monitored persons. The weak correlation between monitored individual doses and biological doses was shown; the biological and physical dose distribution peculiarity in monitored groups is discussed. The distribution of individual aberration frequencies and the average yield of chromosomal exchanges in monitored and non-monitored liquidators were identical. The common cohort analysis (monitored and non-monitored persons) showed that the individual aberration yields distribution among liquidators was strictly randomised in accordance with Poissonian statistics. The cytogenetic dose estimations obtained can be of great value for somatic effects risk assessment in post-Chernobyl cohorts

  1. Study and development of radiothermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Portal, Guy.

    1978-11-01

    After briefly reviewing bibliography concerning the mechanism of radiothermoluminescence and its use in dosimetry, we have concentrated on studies of three thermoluminescent products: magnesium activated lithium fluoride, alumina and calcium sulfate activated with either dysprosium or thulium. In particular, the preparation and singular properties of a new type of lithium fluoride stabilised with sodium, created especially for dosimetric purposes, is described. The physical characteristics of these three products, their emission spectra and their trap parameters, have been studied and we have analysed, both theoretically and experimentally, their dosimetric properties, paying particular attention to their relative chromatic sensitivity to photons and neutrons. It is shown that alumina exhibits an exceptional neutron thermoluminescent yield which points to a potential interest in this material which is little used to date. The deep trapping levels of these products have been studied and some levels found appearing at temperatures above 600 0 C: these can be used for radiation dosimetry in enclosures at temperatures between 400 and 450 0 C. Finally, a brief outline of radiothermoluminescent applications of these products in the radioprotection, medical, biological, archeological and industrial fields is presented [fr

  2. Role of cytogenetic techniques in biological dosimetry of absorbed radiation

    International Nuclear Information System (INIS)

    Rao, B.S.

    2016-01-01

    In most of the radiation accidents, physical dosimetric information is rarely available. Further, most of the accidental exposures are non-uniform involving either partial body or localized exposure to significant doses. In such situations, physical dosimetry does not provide reliable dose estimate. It has now been realized that biological dosimetric techniques can play an important role in the assessment of absorbed dose. In recent years, a number of biological indicators of radiation have been identified. These include the kinetics of onset and persistence of prodromal syndromes (radiation sickness), cytogenetic changes in peripheral blood lymphocytes, hematological changes, biochemical indicators, ESR spectroscopy of biological samples, induction of gene mutations in red blood cells, cytogenetic and physiological changes in skin and neurophysiological changes. In general, dosimetric information is derived by a combination of several different methods, as they have potential to serve as prognostic indicators. The role of cytogenetic techniques in peripheral blood lymphocytes (PBL) as biological indicators of absorbed radiation is reviewed here

  3. Biological and clinical dosimetry, July 1, 1964 to December 31, 1984. Final report

    International Nuclear Information System (INIS)

    Laughlin, J.S.; Zeitz, L.

    1986-01-01

    The goal was to develop systems for the determination of absorbed dose in biological research and clinical applications. The primary method under study is the local absorbed dose calorimeter. In addition, secondary dosimetric systems such as ionization chambers, chemical dosimeters and thermoluminescent dosimeters (TLD) are being developed and applied to provide an absolute basis for the evaluation and comparison of experiments, treatments and other procedures using radiation. In keeping with these objectives this project has accomplished significant advances in the following areas: (1) local absorbed dose calorimetry; (2) neutron dosimetry; (3) dosimetry of ultra-high intensity radiation sources; (4) solid state detector and germanium gamma camera program; (5) dosimetry for brachytherapy; and (6) ''non-isolated sensor'' calorimeters

  4. Chromosome aberration analysis for biological dosimetry: a review

    International Nuclear Information System (INIS)

    Paul, S.F.D.; Venkatachalam, P.; Jeevanram, R.K.

    1996-01-01

    Among various biological dosimetry techniques, dicentric chromosome aberration method appears to be the method of choice in analysing accidental radiation exposure in most of the laboratories. The major advantage of this method is its sensitivity as the number of dicentric chromosomes present in control population is too small and more importantly radiation induces mainly dicentric chromosome aberration among unstable aberration. This report brings out the historical development of various cytogenetic methods, the basic structure of DNA, chromosomes and different forms of chromosome aberrations. It also highlights the construction of dose-response curve for dicentric chromosome and its use in the estimation of radiation dose. (author)

  5. Biological dosimetry: chromosomal aberration analysis for dose assessment

    International Nuclear Information System (INIS)

    1986-01-01

    In view of the growing importance of chromosomal aberration analysis as a biological dosimeter, the present report provides a concise summary of the scientific background of the subject and a comprehensive source of information at the technical level. After a review of the basic principles of radiation dosimetry and radiation biology basic information on the biology of lymphocytes, the structure of chromosomes and the classification of chromosomal aberrations are presented. This is followed by a presentation of techniques for collecting blood, storing, transporting, culturing, making chromosomal preparations and scaring of aberrations. The physical and statistical parameters involved in dose assessment are discussed and examples of actual dose assessments taken from the scientific literature are given

  6. An improved in vitro micronucleus assay to biological dosimetry

    International Nuclear Information System (INIS)

    Ocampo, Ivette Z.; Okazaki, Kayo; Vieira, Daniel P.

    2013-01-01

    The biological dosimetry is widely used to estimate the absorbed dose in people occupationally or accidentally exposed to the radiation for a better medical treatment, minimizing the harmful effects. Many techniques and methods have been proposed to detect and quantify the radioinduced lesions in genetic material, among them, the micronucleus (MN) assay. In the present study, we proposed an improved in vitro micronucleus technique that is rapid, sensitive and with minor cell manipulations. Assays were carried out with human tumor cells (MCF-7) seeded (3x10 4 cells) in slides placed into Petri dishes. Adherent cells were maintained with RPMI medium, supplemented with fetal calf serum, 1 % antibiotics, cytochalasin B (2 μg/mL), and incubated at 37 deg C in the presence of 5% CO2 for 72h. Cells were pre-treated for 24h with aminoguanidine, a nitric oxide synthase inhibitor. Nitric oxide is an intracellular free-radical, involved in DNA double-strand break repair mechanisms. After incubation, adherent cells on slides were briefly fixed with paraformaldehyde and stained with acridine orange (100 μg/mL) for analysis through fluorescence microscopy. Dye fluorescence permitted accurate discrimination between nuclei and micronuclei (bright green) and cytoplasm (red), and made possible a faster counting of binucleated cells. Aminoguanidine (2 mM) induced significant increase (p< 0.05) in frequencies of binucleated cells with micronuclei and in the number of micronuclei per binucleated cell. Data showed that proposed modifications permit to understand an early aspect of NO inhibition and suggested an improved protocol to MN assays. (author)

  7. The method validation step of biological dosimetry accreditation process

    International Nuclear Information System (INIS)

    Roy, L.; Voisin, P.A.; Guillou, A.C.; Busset, A.; Gregoire, E.; Buard, V.; Delbos, M.; Voisin, Ph.

    2006-01-01

    One of the missions of the Laboratory of Biological Dosimetry (L.D.B.) of the Institute for Radiation and Nuclear Safety (I.R.S.N.) is to assess the radiological dose after an accidental overexposure suspicion to ionising radiation, by using radio-induced changes of some biological parameters. The 'gold standard' is the yield of dicentrics observed in patients lymphocytes, and this yield is converted in dose using dose effect relationships. This method is complementary to clinical and physical dosimetry, for medical team in charge of the patients. To obtain a formal recognition of its operational activity, the laboratory decided three years ago, to require an accreditation, by following the recommendations of both 17025 General Requirements for the Competence of Testing and Calibration Laboratories and 19238 Performance criteria for service laboratories performing biological dosimetry by cyto-genetics. Diagnostics, risks analysis were realized to control the whole analysis process leading to documents writing. Purchases, personnel department, vocational training were also included in the quality system. Audits were very helpful to improve the quality system. One specificity of this technique is that it is not normalized therefore apart from quality management aspects, several technical points needed some validations. An inventory of potentially influent factors was carried out. To estimate their real effect on the yield of dicentrics, a Placket-Burman experimental design was conducted. The effect of seven parameters was tested: the BUdr (bromodeoxyuridine), PHA (phytohemagglutinin) and colcemid concentration, the culture duration, the incubator temperature, the blood volume and the medium volume. The chosen values were calculated according to the uncertainties on the way they were measured i.e. pipettes, thermometers, test tubes. None of the factors has a significant impact on the yield of dicentrics. Therefore the uncertainty linked to their use was considered as

  8. The method validation step of biological dosimetry accreditation process

    Energy Technology Data Exchange (ETDEWEB)

    Roy, L.; Voisin, P.A.; Guillou, A.C.; Busset, A.; Gregoire, E.; Buard, V.; Delbos, M.; Voisin, Ph. [Institut de Radioprotection et de Surete Nucleaire, LDB, 92 - Fontenay aux Roses (France)

    2006-07-01

    One of the missions of the Laboratory of Biological Dosimetry (L.D.B.) of the Institute for Radiation and Nuclear Safety (I.R.S.N.) is to assess the radiological dose after an accidental overexposure suspicion to ionising radiation, by using radio-induced changes of some biological parameters. The 'gold standard' is the yield of dicentrics observed in patients lymphocytes, and this yield is converted in dose using dose effect relationships. This method is complementary to clinical and physical dosimetry, for medical team in charge of the patients. To obtain a formal recognition of its operational activity, the laboratory decided three years ago, to require an accreditation, by following the recommendations of both 17025 General Requirements for the Competence of Testing and Calibration Laboratories and 19238 Performance criteria for service laboratories performing biological dosimetry by cyto-genetics. Diagnostics, risks analysis were realized to control the whole analysis process leading to documents writing. Purchases, personnel department, vocational training were also included in the quality system. Audits were very helpful to improve the quality system. One specificity of this technique is that it is not normalized therefore apart from quality management aspects, several technical points needed some validations. An inventory of potentially influent factors was carried out. To estimate their real effect on the yield of dicentrics, a Placket-Burman experimental design was conducted. The effect of seven parameters was tested: the BUdr (bromodeoxyuridine), PHA (phytohemagglutinin) and colcemid concentration, the culture duration, the incubator temperature, the blood volume and the medium volume. The chosen values were calculated according to the uncertainties on the way they were measured i.e. pipettes, thermometers, test tubes. None of the factors has a significant impact on the yield of dicentrics. Therefore the uncertainty linked to their use was

  9. RENEB - Running the European Network of biological dosimetry and physical retrospective dosimetry.

    Science.gov (United States)

    Kulka, Ulrike; Abend, Michael; Ainsbury, Elizabeth; Badie, Christophe; Barquinero, Joan Francesc; Barrios, Lleonard; Beinke, Christina; Bortolin, Emanuela; Cucu, Alexandra; De Amicis, Andrea; Domínguez, Inmaculada; Fattibene, Paola; Frøvig, Anne Marie; Gregoire, Eric; Guogyte, Kamile; Hadjidekova, Valeria; Jaworska, Alicja; Kriehuber, Ralf; Lindholm, Carita; Lloyd, David; Lumniczky, Katalin; Lyng, Fiona; Meschini, Roberta; Mörtl, Simone; Della Monaca, Sara; Monteiro Gil, Octávia; Montoro, Alegria; Moquet, Jayne; Moreno, Mercedes; Oestreicher, Ursula; Palitti, Fabrizio; Pantelias, Gabriel; Patrono, Clarice; Piqueret-Stephan, Laure; Port, Matthias; Prieto, María Jesus; Quintens, Roel; Ricoul, Michelle; Romm, Horst; Roy, Laurence; Sáfrány, Géza; Sabatier, Laure; Sebastià, Natividad; Sommer, Sylwester; Terzoudi, Georgia; Testa, Antonella; Thierens, Hubert; Turai, Istvan; Trompier, François; Valente, Marco; Vaz, Pedro; Voisin, Philippe; Vral, Anne; Woda, Clemens; Zafiropoulos, Demetre; Wojcik, Andrzej

    2017-01-01

    A European network was initiated in 2012 by 23 partners from 16 European countries with the aim to significantly increase individualized dose reconstruction in case of large-scale radiological emergency scenarios. The network was built on three complementary pillars: (1) an operational basis with seven biological and physical dosimetric assays in ready-to-use mode, (2) a basis for education, training and quality assurance, and (3) a basis for further network development regarding new techniques and members. Techniques for individual dose estimation based on biological samples and/or inert personalized devices as mobile phones or smart phones were optimized to support rapid categorization of many potential victims according to the received dose to the blood or personal devices. Communication and cross-border collaboration were also standardized. To assure long-term sustainability of the network, cooperation with national and international emergency preparedness organizations was initiated and links to radiation protection and research platforms have been developed. A legal framework, based on a Memorandum of Understanding, was established and signed by 27 organizations by the end of 2015. RENEB is a European Network of biological and physical-retrospective dosimetry, with the capacity and capability to perform large-scale rapid individualized dose estimation. Specialized to handle large numbers of samples, RENEB is able to contribute to radiological emergency preparedness and wider large-scale research projects.

  10. Non-invasive biological dosimetry of the skin

    International Nuclear Information System (INIS)

    Barton, S.; Marks, R.; Charles, M.W.; Wells, J.

    1986-01-01

    Investigations designed to identify a potential biological dosimetry technique to examine the effects of X-ray doses down to 0.1 Gy on human skin, are described. In a variety of parameters assessed, the most important changes observed were a significant depression in epidermal cell production in the basal layer after X-ray doses between 0.5 Gy and 1 Gy and a concomitant reduction in the desquamation rate of corneocytes after doses above 1 Gy. Changes in non-specific esterase (NSE) activity were also observed. Further work is described which applies these results to several non-invasive techniques which may have potential for routine application. Preliminary data from irradiated human skin are presented on the measurement of forced desquamation, the evaluation of NSE activity from hair samples and the evaluation of stratum corneum turnover time using the fluorescent dye, dansyl chloride. (author)

  11. Calibration Curves for Biological Dosimetry by Fluorescence In situ Hybridisation

    International Nuclear Information System (INIS)

    Stonati, L.; Durante, M.; Gensabella, G.; Gialanella, G.; Grossi, G.F.; Pugliese, M.; Scampoli, P.; Sgura, A.; Testa, A.; Tanzarella, C.

    2001-01-01

    Dose-response curves were measured for the induction of chromosomal aberrations in peripheral blood lymphocytes after acute exposure in vitro to 60 Co γ rays. Blood was obtained from four different healthy donors, and chromosomes were either observed at metaphase, following colcemid accumulation, or prematurely condensed by calyculin A. Cells were analysed in three different Italian laboratories. Chromosomes 1, 2, and 4 were painted, and simple-type interchanges between painted and non-painted chromosomes were scored in cells exposed in the dose range 0.1-3.0 Gy. The chemical-induced premature chromosome condensation method was also used combined with chromosome painting (chromosome 4 only) to determine calibration curves for high dose exposures (up to 20 Gy X rays). Calibration curves described in this paper will be used in our laboratories for biological dosimetry by fluorescence in situ hybridisation. (author)

  12. Towards Establishing Capacity for Biological Dosimetry at Ghana Atomic Energy Commission.

    Science.gov (United States)

    Achel, Daniel Gyingiri; Achoribo, Elom; Agbenyegah, Sandra; Adaboro, Rudolph M; Donkor, Shadrack; Adu-Bobi, Nana A K; Agyekum, Akwasi A; Akuamoa, Felicia; Tagoe, Samuel N; Kyei, Kofi A; Yarney, Joel; Serafin, Antonio; Akudugu, John M

    2016-01-01

    The aim of this study was not only to obtain basic technical prerequisites for the establishment of capacity of biological dosimetry at the Ghana Atomic Energy Commission (GAEC) but also to stimulate interest in biological dosimetry research in Ghana and Sub-Saharan Africa. Peripheral blood from four healthy donors was exposed to different doses (0-6 Gy) of gamma rays from a radiotherapy machine and lymphocytes were subsequently stimulated, cultured, and processed according to standard protocols for 48-50 h. Processed cells were analyzed for the frequencies of dicentric and centric ring chromosomes. Radiation dose delivered to the experimental model was verified using GafChromic® EBT films in parallel experiments. Basic technical prerequisites for the establishment of capacity of biological dosimetry in the GAEC have been realized and expertise in the dicentric chromosome assay consolidated. We successfully obtained preliminary cytogenetic data for a dose-response relationship of the irradiated blood lymphocytes. The data strongly indicate the existence of significant linear (α) and quadratic (β) components and are consistent with those published for the production of chromosome aberrations in comparable absorbed dose ranges.

  13. Biological dosimetry for mixed gamma-neutron field

    International Nuclear Information System (INIS)

    Brandao, J.O.C.; Santos, J.A.L.; Souza, P.L.G.; Lima, F.F.; Vilela, E.C.; Calixto, M.S.; Santos, N.

    2011-01-01

    There is increasing concern about airline crew members (about one million worldwide) exposed to measurable neutrons doses. Historically, cytogenetic biodosimetry assays have been based on quantifying asymmetrical chromosome alterations (dicentrics, centric rings and acentric fragments) in mitogen-stimulated T-lymphocytes in their first mitosis after radiation exposure. Increased levels of chromosome damage in peripheral blood lymphocytes are a sensitive indicator of radiation exposure and they are routinely exploited for assessing radiation absorbed dose after accidental or occupational exposure. Since radiological accidents are not common, not all nations feel that it is economically justified to maintain biodosimetry competence. However, dependable access to biological dosimetry capabilities is completely critical in event of an accident. In this paper the dose-response curve was measured for the induction of chromosomal alterations in peripheral blood lymphocytes after chronic exposure in vitro to mixed gamma-neutron field. Blood was obtained from one healthy donor and exposed to two mixed gamma-neutron field from sources 241 AmBe (20 Ci) at the Neutron Calibration Laboratory (NCL - CRCN/NE - PE - Brazil). The evaluated absorbed doses were 0.2 Gy; 1.0 Gy and 2.5 Gy. The dicentric chromosomes were observed at metaphase, following colcemide accumulation and 1000 well-spread metaphases were analyzed for the presence of dicentrics by two experts after painted by giemsa 5%. The preliminary results showed a linear dependence between radiations absorbed dose and dicentric chromosomes frequencies. Dose-response curve described in this paper will contribute to the construction of calibration curve that will be used in our laboratory for biological dosimetry. (author)

  14. Developments in biological dosimetry for the nuclear industry

    Energy Technology Data Exchange (ETDEWEB)

    Gale, K L; Boreham, D R; Maves, S; Morrison, D P [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

    1996-12-31

    The purpose of this program is to develop methods for providing estimates of radiation exposure based on changes in the cells/tissues of exposed individuals. This work arises from the need for independent measures of exposure of workers when standard dose measurements are unavailable or questionable. The radiation-induced changes that we propose to measure have been correlated with carcinogenesis. It follows that the methods used should also provide indications of the likely biological consequences of radiation exposure for an individual. The consequences of radiation exposure lie in the resolution of the radiation effects at the cellular level. Accordingly, it is at the cellular level that our attention is directed. More precisely, since the consequences of most concern, cancer induction and the induction of inherited diseases, are the result of changes to the genetic material of cells (the DNA), it is the measurement of effects on DNA that are being investigated as possible dose meters. Individuals are unique in terms of their DNA and differ in their cellular capacities to repair the damage from an ionizing radiation dose. Because of these features, not only do biological dosimetry tools offer us a means of measuring a dose at the individual level but may also provide us with a measure of the ultimate risk associated with a given exposure. (author). 7 refs., 2 tabs., 4 figs.

  15. Developments in biological dosimetry for the nuclear industry

    International Nuclear Information System (INIS)

    Gale, K.L.; Boreham, D.R.; Maves, S.; Morrison, D.P.

    1995-01-01

    The purpose of this program is to develop methods for providing estimates of radiation exposure based on changes in the cells/tissues of exposed individuals. This work arises from the need for independent measures of exposure of workers when standard dose measurements are unavailable or questionable. The radiation-induced changes that we propose to measure have been correlated with carcinogenesis. It follows that the methods used should also provide indications of the likely biological consequences of radiation exposure for an individual. The consequences of radiation exposure lie in the resolution of the radiation effects at the cellular level. Accordingly, it is at the cellular level that our attention is directed. More precisely, since the consequences of most concern, cancer induction and the induction of inherited diseases, are the result of changes to the genetic material of cells (the DNA), it is the measurement of effects on DNA that are being investigated as possible dose meters. Individuals are unique in terms of their DNA and differ in their cellular capacities to repair the damage from an ionizing radiation dose. Because of these features, not only do biological dosimetry tools offer us a means of measuring a dose at the individual level but may also provide us with a measure of the ultimate risk associated with a given exposure. (author). 7 refs., 2 tabs., 4 figs

  16. Statistical issues in biological radiation dosimetry for risk assessment using stable chromosome aberrations

    International Nuclear Information System (INIS)

    Cologne, J.B.; Preston, D.L.

    1998-01-01

    Biological dosimeters are useful for epidemiologic risk assessment in populations exposed to catastrophic nuclear events and as a means of validating physical dosimetry in radiation workers. Application requires knowledge of the magnitude of uncertainty in the biological dose estimates and an understanding of potential statistical pitfalls arising from their use. This paper describes the statistical aspects of biological dosimetry in general and presents a detailed analysis in the specific case of dosimetry for risk assessment using stable chromosome aberration frequency. Biological dose estimates may be obtained from a dose-response curve, but negative estimates can result and adjustment must be made for regression bias due to imprecise estimation when the estimates are used in regression analyses. Posterior-mean estimates, derived as the mean of the distribution of true doses compatible with a given value of the biological endpoint, have several desirable properties: they are nonnegative, less sensitive to extreme skewness in the true dose distribution, and implicitly adjusted to avoid regression bias. The methods necessitate approximating the true-dose distribution in the population in which biological dosimetry is being applied, which calls for careful consideration of this distribution through other information. An important question addressed here is to what extent the methods are robust to misspecification of this distribution, because in many applications of biological dosimetry it cannot be characterized well. The findings suggest that dosimetry based solely on stable chromosome aberration frequency may be useful for population-based risk assessment

  17. Usefulness and limits of biological dosimetry based on cytogenetic methods

    International Nuclear Information System (INIS)

    Leonard, A.; Rueff, J.; Gerber, G. B.; Leonard, E. D.

    2005-01-01

    Damage from occupational or accidental exposure to ionising radiation is often assessed by monitoring chromosome aberrations in peripheral blood lymphocytes, and these procedures have, in several cases, assisted physicians in the management of irradiated persons. Thereby, circulating lymphocytes, which are in the G0 stage of the cell cycle are stimulated with a mitogenic agent, usually phytohaemagglutinin, to replicate in vitro their DNA and enter cell division, and are then observed for abnormalities. Comparison with dose response relationships obtained in vitro allows an estimate of exposure based on scoring: - Unstable aberrations by the conventional, well-established analysis of metaphases for chromosome abnormalities or for micronuclei; - So-called stable aberrations by the classical G-banding (Giemsa-Stain-banding) technique or by the more recently developed fluorescent in situ hybridisation (FISH) method using fluorescent-labelled probes for centromeres and chromosomes. Three factors need to be considered in applying such biological dosimetry: (1) Radiation doses in the body are often inhomogeneous. A comparison of the distribution of the observed aberrations among with that expected from a normal poisson distribution can allow conclusions to be made with regard to the inhomogeneity of exposure by means of the so-called contaminated poisson distribution method; however, its application requires a sufficiently large number of aberrations, i.e. an exposure to a rather large dose at a high dose rate. (2) Exposure can occur at a low dose rate (e.g. from spread or lost radioactive sources) rendering a comparison with in vitro exposure hazardous. Dose-effect relationships of most aberrations that were scored, such as translocations, follow a square law. Repair intervening during exposure reduces the quadratic component with decreasing dose rate as exposure is spread over a longer period of time. No valid solution for this problem has yet been developed, although

  18. Transient impedance changes in venous endothelial monolayers as a biological radiation dosimetry response

    Directory of Open Access Journals (Sweden)

    Erik Fossum Young

    2012-10-01

    Full Text Available In March of 2011, a magnitude 9.0 earthquake and subsequent 14 m-high tsunami caused major damage to the Fukushima Daiichi nuclear power plant in Japan.  While cancer incidence in the radiation-exposed population is a logical concern, the complex effects of radiation on the heart and cardiovascular system are also of interest.  Immediate and early vascular radiation effects could be exploited as a dosimetry modality.  To test whether non-coronary vasculature exhibited transient perturbation in barrier function, video microscopy studies and Electric Cell Substrate Impedance Sensing technology were used to probe very subtle changes in primary human vascular endothelium.  Human umbilical vein endothelial cell (HUVEC monolayers exhibit a transient, statistically significant decrease (P = 0.017 in monolayer resistance 3 h after irradiation with 5.0 Gy of g rays.  Radiation induced perturbations in HUVEC monolayer permeability are similar in magnitude and kinetics to those observed in coronary arterial endothelium.  Therefore, at least two types of vasculature respond to radiation on ECIS arrays with an early transient disruption in permeability.  The finding supports the use of early passage HUVECs for use in bioelectric dosimetry studies of vasculature and suggests that permeability of vessels could potentially serve as a biological dosimetry tool.

  19. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-15

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, gamma) process in Na sup 2 sup 3 , giving rise to Na sup 2 sup 4 , which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na sup 2 sup 4 , is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na sup 2 sup 3 in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na sup 2 sup 4 /Na sup 2 sup 3 in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R sub B reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzmann transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given

  20. Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, G S; Ritchie, R H; Sanders, F W; Reinhardt, P W; Auxier, J A; Wagner, E B; Callihan, A D; Morgan, K Z [Health Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

    1962-03-01

    The methods of dosimetry used for investigation of the doses received by the individuals exposed in the Yugoslav accident were essentially those used in connection with the Oak Ridge Y-12 accident. An outline of the general scheme is as follows: When fast neutrons enter the human body, most of these are moderated to thermal energy and a small fraction of these are captured by a (n, {gamma}) process in Na{sup 23}, giving rise to Na{sup 24}, which by virtue of its emission of high-energy gamma rays with a half life of 14.8 h, is easily detected. It has been shown that the probability of capture, making Na{sup 24}, is not a strong function of the energy of the fast neutrons and that the probability of capture for neutrons is higher in the fast region than in the thermal region. Thus, the uniform distribution of Na{sup 23} in the human body provides an excellent means of normalizing the neutron exposure of an individual. in particular, for a given neutron energy spectrum the fast neutron dose is proportional to the ratio Na{sup 24}/Na{sup 23} in the body or in the blood system. This method of normalization is quite important in the dosimetry of radiation accidents since no assumptions need be made about the exact location of an individual at the time of the energy release. The importance of this fact can be made clear by reference to the Y-12 accident where it was shown by calculation of the neutron dose based on the known number of fissions and the stated location of the individual that one of the surviving individuals would have received a dose several times the lethal value. To accomplish the measurements described, the zero power R{sub B} reactor was operated in two ranges of power level, 'low' power and 'high 'power. Neutron leakage spectrum was obtained by multigroup approximation of the Boltzman transport equation. Prompt gamma rays from fission products, from capture in the moderator and fuel cladding as well as in tank walls are given. A summary of the 4{pi

  1. Protocol for X-ray dosimetry and exposure arrangements employed in studies of late somatic effects in mammals

    International Nuclear Information System (INIS)

    Zoetelief, J.; Kogel, A.J. van der; Broerse, J.J.; Scarpa, G.; Dixon-Brown, A.

    1985-01-01

    A number of European laboratories studying the late effects of ionizing radiation in animals have established an effective cooperation within the European Late Effects Project Group (EULEP) since 1970. To facilitate the exchange of biological results several techniques, including quality control of the experimental animals, pathology and dosimetry, have to be standardized. The most important aspects of the procedures for X-irradiation and dosimetry of small animals are summarized. These include recommendations on irradiation conditions, dosimetry methods, characteristics of phantoms and factors affecting X-ray dosimetry. X-irradiation procedures employed by the participating institutes are described and the results of five X-ray dosimetry intercomparisons are reported. The introduction of a common dosimetry protocol has resulted in improvements in exposure arrangements and absolute dosimetry. (author)

  2. Conventional radiation-biological dosimetry using frequencies of unstable chromosome aberrations

    International Nuclear Information System (INIS)

    Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S.

    1998-01-01

    Frequency of chromosome aberrations detected by conventional cytogenetics is a very useful parameter in biological radiodosimetry. It can be used for estimating absorbed doses in individuals working with radioactive sources and individuals accidentally exposed to radiation. In the first case subjects wear physical dosimeters as a routine safety habit. The laboratory at the Institute of Radioprotection and Dosimetry (IRD, Brazil) has been using conventional cytogenetic analysis to complement data obtained by physical dosimetry since 1983. Until now, more than one hundred cases were investigated where individual physical dosimeters detected occupational exposure (above the safety limits allowed). In total, only 34% of these cases were confirmed by conventional cytogenetic dosimetry. Also, conventional cytogenetic analysis following the radiation accident of Goiania (Brazil) in 1987 have been used. Peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequencies of unstable chromosomal aberrations (dicentrics, centric rings and acentrics fragments) to estimate absorbed radiation doses. During the emergency period, doses were estimated to help immediate medical treatment using in vitro calibration curves produced before the accident. Later on, doses were assessed once more using new in vitro calibration curves. A drawback of this technique is that unstable aberrations are lost after exposure. To investigate the mean lifespan of lymphocytes containing dicentric and ring aberrations, we have followed 15 victims of the Goiania accident over all these years. Results suggest that the disappearance of unstable aberrations is dose-dependent. This could explain the variation in the results found among studies in this field

  3. Conventional radiation-biological dosimetry using frequencies of unstable chromosome aberrations

    Energy Technology Data Exchange (ETDEWEB)

    Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S. [Institute of Radioprotection and Dosimetry (IRD), National Commission of Nuclear Energy (CNEN), Av. Salvador Allende, Cx. P. 37750, Rio de Janeiro 22.780-160 (Brazil)

    1998-08-03

    Frequency of chromosome aberrations detected by conventional cytogenetics is a very useful parameter in biological radiodosimetry. It can be used for estimating absorbed doses in individuals working with radioactive sources and individuals accidentally exposed to radiation. In the first case subjects wear physical dosimeters as a routine safety habit. The laboratory at the Institute of Radioprotection and Dosimetry (IRD, Brazil) has been using conventional cytogenetic analysis to complement data obtained by physical dosimetry since 1983. Until now, more than one hundred cases were investigated where individual physical dosimeters detected occupational exposure (above the safety limits allowed). In total, only 34% of these cases were confirmed by conventional cytogenetic dosimetry. Also, conventional cytogenetic analysis following the radiation accident of Goiania (Brazil) in 1987 have been used. Peripheral lymphocytes from 129 exposed or potentially exposed individuals were analyzed for the frequencies of unstable chromosomal aberrations (dicentrics, centric rings and acentrics fragments) to estimate absorbed radiation doses. During the emergency period, doses were estimated to help immediate medical treatment using in vitro calibration curves produced before the accident. Later on, doses were assessed once more using new in vitro calibration curves. A drawback of this technique is that unstable aberrations are lost after exposure. To investigate the mean lifespan of lymphocytes containing dicentric and ring aberrations, we have followed 15 victims of the Goiania accident over all these years. Results suggest that the disappearance of unstable aberrations is dose-dependent. This could explain the variation in the results found among studies in this field

  4. Effect of contrast agent administration on consequences of dosimetry and biology in radiotherapy planning

    International Nuclear Information System (INIS)

    Lo, Ching-Jung; Yang, Pei-Ying; Chao, Tsi-Chian; Tu, Shu-Ju

    2015-01-01

    In the treatment planning of radiation therapy, patients may be administrated with contrast media in CT scanning to assist physicians for accurate delineation of the target or organs. However, contrast media are not used in patients during the treatment delivery. In particular, contrast media contain materials with high atomic numbers and dosimetric variations may occur between scenarios where contrast media are present in treatment planning and absent in treatment delivery. In this study we evaluate the effect of contrast media on the dosimetry and biological consequence. An analytical phantom based on AAPM TG 119 and five sets of CT images from clinical patients are included. Different techniques of treatment planning are considered, including 1-field AP, 2-field AP+PA, 4-field box, 7-field IMRT, and RapidArc. RapidArc is a recent technique of volumetric modulated arc therapy and is used in our study of contrast media in clinical scenarios. The effect of RapidArc on dosimetry and biological consequence for administration of contrast media in radiotherapy is not discussed previously in literature. It is shown that dose difference is reduced as the number of external beams is increased, suggesting RapidArc may be favored to be used in the treatment planning enhanced by contrast media. Linear trend lines are fitted for assessment of percent dose differences in the planning target volume versus concentrations of contrast media between plans where contrast media are present and absent, respectively

  5. Studies in dosimetry using stimulated exoelectron emission

    International Nuclear Information System (INIS)

    Petel, Maurice.

    1976-06-01

    Some applications of the stimulated exoelectron emission in radiation dosimetry are discussed. The principles which govern the phenomenon are presented. The apparatus, in particular the counter, used to monitor the emission is discussed with reference to both optical and thermal stimulation. The correlation existing between thermoluminescence and thermally stimulated exoelectron emission were studied in both lithium fluoride and aluminium oxide. Furthermore, aluminium oxides from different sources were examined, and one of these, chosen to investigate the dosimetric properties of this material using both methods of stimulation [fr

  6. Internal dosimetry for epidemiologic studies

    International Nuclear Information System (INIS)

    Groer, P.G.

    1987-01-01

    In traditional epidemiologic analyses, a single valued summary index, the standardized mortality ratio (SMR), is quite popular. The SMR is simply the ratio of the number of deaths observed in the study population to the number of deaths expected if the study population were subject to the age-specific rates of a standard population. SMRs for all causes or specific causes can be calculated. For such a simple analysis an exposed cohort is often characterized by an average organ or whole body dose or dose interval, and the necessary dose estimation effort is relatively minor. Modern statistical methods focus on the estimation of the cause-specific mortality rate λ for study populations exposed to ionizing radiations or toxic chemicals. The dependence of λ on factors other than demographic characteristics, such as race and sex, is usually described through a parametric model. Such factors, often called covariates or covariables, are incorporated in the mathematical expression for the hazard rate. The external gamma dose or the internal lung dose from inhaled uranium are good examples for covariates. This type of analysis permits the use of individual doses and gives a detailed and quantitative description of the mortality rate as a function of the covariables, but at the cost of a major dosimetric effort. The generation of the necessary dose information and also the calculational efforts become especially taxing for time-dependent covariates such as an internal, cumulative organ dose. 4 refs

  7. Dosimetry using environmental and biological materials. Final report

    International Nuclear Information System (INIS)

    Haskell, E.; Kenner, G.; Hayes, R.

    1998-02-01

    This report summarizes a five year effort to improve the sensitivity and reliability of retrospective dosimetry methods, to collaborate with laboratories engaged in related research and to share the technology with startup laboratories seeking similar capabilities. This research program has focused on validation of electron paramagnetic resonance (EPR) as a dosimetry tool and on optimization of the technique by reducing the lower limits of detection, simplifying the process of sample preparation and analysis and speeding analysis to allow greater throughput in routine measurement situations. The authors have investigated the dosimetric signal of hard tissues in enamel, deorganified dentin, synthetic carbonated apatites and synthetic hydroxyapatite. This research has resulted in a total of 27 manuscripts which have been published, are in press, or have been submitted for publication. Of these manuscripts, 14 are included in this report and were indexed separately for inclusion in the data base

  8. Biological Dosimetry of In Vitro Irradiation with Radionuclides : Comparison of Whole Blood, Lymphocyte and Buffy Coat Culture

    International Nuclear Information System (INIS)

    Kim, Jong Ho; Lee, Dong Soo; Choi, Chang Woon; Chung, June Key; Lee, Myung Chul; Koh, Chang Soon; Kim, Chong Soon; Kim, Hee Geun; Kang, Duck Won; Song, Myung Jae

    1995-01-01

    The purpose of this study was to establish mononuclear cell cultures such as lymphocytes or buffy coat for the biological dosimetry of in vitro irradiation of the radionuclide Tc-99m in order to exclude the effect of residual doses seen in the cultures of whole blood. Biological dosimetry of Tc-99m on cultured mononuclear cells at doses ranging from 0.05 to 6.00 Gy, by scoring unstable chromosomal aberrations(Ydr) observed in cultured lymphocytes, were performed using peripheral venous blood of healthy normal person. The results showed that; (1) In vitro irradiation of radioisotope in separated lymphocyte or buffy coat showed trace amount af residual doses of isotope after washing. Residual doses of isotopes are increased in proportion tn exposed time and irradiated dose without difference between I-131 anct Tc-99m. (2) We obtained these linear-quadratic dose response equations in lymphocyte and buffy coat culture after in vitro irradiation of Tc-99m, respectively (Ydr = 0,001949 D 2 +0,006279D+ 0.000185; Ydr= 0.002531 D 2 -0.003274 D+0.003488). In conclusion, the linear quadrstic dose response equation from in vitro irradiation of Tc-99m with lymphocyte and buffy coat culture was thought to be useful for assessing Tc-99m indueed biological effects. And mononuclear cell cultures seem to be the most appropriate experimental model for the assessment of biological dosimetry of internal irradiation of radionuclides.

  9. Supporting Treatment Decisions in Patients with Differentiated Thyroid Carcinoma (DTC) under Radioiodine-131 Therapy: Role of Biological Dosimetry Assessment

    International Nuclear Information System (INIS)

    Fadel, A.M.; Chebel, G.M.; Di Giorgio, M.; Vallerga, M.B.; Taja, M.R.; Radl, A.; Bubniak, R.V.; Oneto, A.

    2010-01-01

    Radioiodine-131 therapy is applied in patients with differentiated thyroid carcinoma (DTC), within the therapeutic scheme following thyroidectomy, for the ablation of thyroid remnants and treatment of metastatic disease. Several approaches for the selection of a therapeutic dose were applied. The aim of this therapy is to achieve a lethal dose in the tumor tissue, without exceeding the dose of tolerance in healthy tissues (doses greater than 2 Gy in bone marrow could lead to myelotoxicity). In this work, the treatment protocol used incorporates the assessment by biological dosimetry (BD) for estimating doses to whole body and bone marrow, to tailor patient's treatment. Biological Dosimetry prospective studies conducted on samples from patients with cumulative activities, before and after each therapeutic administration, allows to evaluate DNA damage and repair capacity in peripheral blood lymphocytes. (authors)

  10. Canadian Cytogenetic Emergency network (CEN) for biological dosimetry following radiological/nuclear accidents.

    Science.gov (United States)

    Miller, Susan M; Ferrarotto, Catherine L; Vlahovich, Slavica; Wilkins, Ruth C; Boreham, Douglas R; Dolling, Jo-Anna

    2007-07-01

    To test the ability of the cytogenetic emergency network (CEN) of laboratories, currently under development across Canada, to provide rapid biological dosimetry using the dicentric assay for triage assessment, that could be implemented in the event of a large-scale radiation/nuclear emergency. A workshop was held in May 2004 in Toronto, Canada, to introduce the concept of CEN and recruit clinical cytogenetic laboratories at hospitals across the country. Slides were prepared for dicentric assay analysis following in vitro irradiation of blood to a range of gamma-ray doses. A minimum of 50 metaphases per slide were analyzed by 41 people at 22 different laboratories to estimate the exposure level. Dose estimates were calculated based on a dose response curve generated at Health Canada. There were a total of 104 dose estimates and 96 (92.3%) of them fell within the expected range using triage scoring criteria. Half of the laboratories analyzed 50 metaphases in biological dosimetry. When this network is fully operational, it will be the first of its kind in Canada able to respond to radiological/nuclear emergencies by providing triage quality biological dosimetry for a large number of samples. This network represents an alternate expansion of existing international emergency biological dosimetry cytogenetic networks.

  11. Physical and biological dosimetry at the RA-3 facility for small animal irradiation: preliminary BNCT studies in an experimental model of oral cancer

    International Nuclear Information System (INIS)

    Pozzi, Emiliano; Miller, Marcelo; Thorp, Silvia I.; Heber, Elisa M.; Trivillin, Veronica A.; Zarza, Leandro; Estryk, Guillermo; Schwint, Amanda E.; Nigg, David W.

    2007-01-01

    Boron Neutron Capture Therapy (BNCT) is a binary treatment modality based on the capture reaction that occurs between thermal neutrons and boron-10 atoms that accumulate selectively in tumor tissue, emitting high linear energy transfer (LET), short range (5-9 microns) particles (alpha y 7 Li). Thus, BNCT would potentially target tumor tissue selectively, sparing normal tissue. Herein we evaluated the feasibility of treating experimental oral mucosa tumors with BNCT at RA-3 (CAE) employing the hamster cheek pouch oral cancer model and characterized the irradiation field at the RA-3 facility. We evaluated the therapeutic effect on tumor of BNCT mediated by BPA in the hamster cheek pouch oral cancer model and the potential radio toxic effects in normal tissue. We evidenced a moderate biological response in tumor, with no radio toxic effects in normal tissue following irradiations with no shielding for the animal body. Given the sub-optimal therapeutic response, we designed and built a 6 Li 2 CO 3 shielding for the body of the animal to increase the irradiation dose to tumor, without exceeding normal tissue radio tolerance. The measured absolute magnitude of thermal neutron flux and the characterization of the beam with and without the shielding in place, suggest that the irradiation facility in the thermal column of RA-3 would afford an excellent platform to perform BNCT studies in vitro and in vivo in small experimental animals. The present findings must be confirmed and extended by performing in vivo BNCT radiobiological studies in small experimental animals, employing the shielding device for the animal body. (author) [es

  12. Analysis and assessment of the detriment in interventional radiology using biological dosimetry methods

    International Nuclear Information System (INIS)

    Montoro, A.; Almonacid, M.; Villaescusa, J.I.; Barquinero, J.F.; Rodriguez, P.; Barrios, L.; Verdu, G.; Ramos, M.

    2006-01-01

    Interventional radiologist and staff members usually are exposed to high levels of scattered radiation. As a result, the exposition to radiation procedures can produce detrimental effects that we would have to know. Effective dose is the quantity that better estimates the radiation risk. For this study we have realized an estimation of the radiological detriment to exposed workers of the Hospital la Fe de Valencia. For it, have been used physical doses registered in detectors T.L.D., and doses estimated by biological dosimetry in lymphocytes of peripheral blood. There has been estimated for every case the probability of effect of skin cancer and of non-solid cancers (leukaemia, lymphoma and myeloma), being compared with the baseline probability of natural effect. Biological doses were obtained by extrapolating the yield of dicentrics and translocations to their respective dose -effect curves. The discrepancies observed between physically recorded doses and biological estimated doses indicate that workers did not always wear their dosimeters or the dosimeters were not always in the radiation field. Cytogenetic studies should be extended to more workers to assess the risk derived from their occupational exposure. (authors)

  13. Analysis and assessment of the detriment in interventional radiology using biological dosimetry methods

    Energy Technology Data Exchange (ETDEWEB)

    Montoro, A.; Almonacid, M.; Villaescusa, J.I. [Hospital Univ. la Fe de Valen cian, Servicio de Proteccion Radiologica, Valencia (Spain); Barquinero, J.F.; Rodriguez, P. [Universitat Autonom a de Barcelona, Servicio de Dosimetria Biologica, Unidad de Antropologia, Departamento de Biologia Animal, Vegetal y Ecologia., Barcelona (Spain); Barrios, L. [Universidad Autonoma de Barcelona, Dept. de Biologia Celular y Fisiologia. Unidad de Biologia Celular, Barcelona (Spain); Verdu, G.; Ramos, M. [Universidad Politecnica de Valencia, Dept. de Ingenieria Quimica y Nuclear, Valencia, (Spain)

    2006-07-01

    Interventional radiologist and staff members usually are exposed to high levels of scattered radiation. As a result, the exposition to radiation procedures can produce detrimental effects that we would have to know. Effective dose is the quantity that better estimates the radiation risk. For this study we have realized an estimation of the radiological detriment to exposed workers of the Hospital la Fe de Valencia. For it, have been used physical doses registered in detectors T.L.D., and doses estimated by biological dosimetry in lymphocytes of peripheral blood. There has been estimated for every case the probability of effect of skin cancer and of non-solid cancers (leukaemia, lymphoma and myeloma), being compared with the baseline probability of natural effect. Biological doses were obtained by extrapolating the yield of dicentrics and translocations to their respective dose -effect curves. The discrepancies observed between physically recorded doses and biological estimated doses indicate that workers did not always wear their dosimeters or the dosimeters were not always in the radiation field. Cytogenetic studies should be extended to more workers to assess the risk derived from their occupational exposure. (authors)

  14. Latin-American Biological Dosimetry Network (LBDNET) Intercomparison Exercise. Evaluation through triage and conventional scoring criteria. Development of a new approach for statistical data analysis

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Radl, A.

    2011-01-01

    Biological Dosimetry is a necessary support for National Radiation Protection Programs and Emergency Response Schemes. A Latin-American Biological Dosimetry Network (LBDNET) has been constituted by the biological dosimetry laboratories from: Argentina, Brazil, Chile, Cuba, Mexico, Peru, and Uruguay (IAEA Regional Project RLA9/054, 2007). The biological dosimetry laboratory of Argentina organized an international biological dosimetry intercomparison for the analysis of some relevant parameters involved in dose assessment, to reinforce the response capability in accidental situations requiring the activation of mutual assistance mechanisms and thus, constituting the bases of the LBDNET organization. (authors)

  15. Activities developed by the biological dosimetry laboratory of the Autoridad Regulatoria Nuclear - ARN of Argentina

    International Nuclear Information System (INIS)

    Radl, A.; Sapienza, C.E.; Taja, M.R.; Bubniak, R.; Deminge, M.; Di Giorgio, M.

    2013-01-01

    Biological dosimetry (DB) allows to estimate doses absorbed in individuals exposed to ionizing radiation through the quantification of stable and unstable chromosome aberrations (SCA and UCA). The frequency of these aberrations is referred to a calibration dose response curve (in vitro) to determine the doses of the individual to the whole body. The DB is a necessary support for programs of national radiation protection and response systems in nuclear or radiological emergencies in the event of accidental or incidental, single overexposure or large scale. In this context the Laboratory of Dosimetry Biological (LDB) of the Authority Regulatory Nuclear (ARN) Argentina develops and applies different dosimeters cytogenetic from four decades ago. These dosimeters provide a fact more within the whole of the information necessary for an accidental, complementing the physical and clinical dosimetry exposure assessment. The most widely used in the DB biodosimetric method is the quantification of SCA (dicentrics and rings Central) from a sample of venous blood. The LDB is accredited for the trial, under rules IRAM 301: 2005 (ISO / IEC 17025: 2005) and ISO 19238:2004. Test applies to the immediate dosimetry evaluation of acute exposures, all or a large part of the body in the range 0,1-5 Gy. In this context the LDB is part of the Latin American network of DB (LBDNet), BioDoseNet-who and response system in radiological emergencies and nuclear IAEA-RANET, being enabled to summon the LBDNet if necessary

  16. Dosimetry of internal emitters

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The Dosimetry of Internal Emitter Program endeavors to refine the correlation between radiation dose and observed biological effects. The program is presently engaged in the development of studies that will demonstrate the applicability of microdosimetry models developed under the Microdosimetry of Internal Sources Program. The program also provides guidance and assistance to Pacific Northwest Laboratory's Biology Department in the dosimetric analysis of internally deposited radionuclides. This report deals with alpha particle dosimetry plutonium 239 inhalation, and in vitro studies of chromosomal observations

  17. Radiation effects analysis in a group of interventional radiologists using biological and physical dosimetry methods

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, M., E-mail: WEMLmirapas@iqn.upv.e [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Montoro, A.; Almonacid, M. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Ferrer, S. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Barquinero, J.F. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Tortosa, R. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain); Verdu, G. [Department of Chemical and Nuclear Engineering, Polytechnic University of Valencia, Camino de Vera s/n, 46022 Valencia (Spain); Rodriguez, P. [Biological Dosimetry Service, Unit of Anthropology, Department of Animal and Vegetable Biology and Ecology, Universitat Autonoma de Barcelona (UAB) (Spain); Barrios, L.L. [Department of Physiology and Cellular Biology, Unit of Cellular Biology (UAB) (Spain); Villaescusa, J.I. [Radiation Protection Service, Hospital Universitario La Fe Valencia (Spain)

    2010-08-15

    excess radio-induced risk of leukemia in the group under study. Finally, the maximum radiological detriment in the group, evaluated as the total number of radio-induced cancers using physical dosimetry, has been of 2.18/1000 person-year (skin and leukemia), and using biological dosimetry of 9.20/1000 PY (leukemia). As a conclusion, this study has provided an assessment of the non-deterministic effects (rate of radio-induced cancer incidence) attributable to the group under study due to their professional activity.

  18. Characterization and evaluation studies on some JAERI dosimetry systems

    International Nuclear Information System (INIS)

    Kojima, T.; Sunaga, H.; Tachibana, H.; Takizawa, H.; Tanaka, R.

    2000-01-01

    Characterization and evaluation studies were carried out on some JAERI dosimetry systems, mainly alanine-ESR, in terms of the influence on the dose response of parameters such as orientation at ESR analysis, and the temperature during irradiation and analysis. Feasibility study for application of these dosimetry systems to electrons with energies lower than 4 MeV and bremsstrahlung (X rays) was also performed parallel to their reliability check through international dose intercomparison. (author)

  19. Biological dosimetry by the triage dicentric chromosome assay - Further validation of international networking

    Energy Technology Data Exchange (ETDEWEB)

    Wilkins, Ruth C., E-mail: Ruth.Wilkins@hc-sc.gc.ca [Health Canada, Ottawa, ON K1A 0K9 (Canada); Romm, Horst; Oestreicher, Ursula [Bundesamt fur Strahlenschutz, 38226 Salzgitter (Germany); Marro, Leonora [Health Canada, Ottawa, ON K1A 0K9 (Canada); Yoshida, Mitsuaki A. [Biological Dosimetry Section, Dept. of Dose Assessment, Research Center for Radiation Emergency Medicine, NIRS, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Department Radiation Biology, Institute of Radiation Emergency Medicine, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Suto, Y. [Biological Dosimetry Section, Dept. of Dose Assessment, Research Center for Radiation Emergency Medicine, NIRS, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Prasanna, Pataje G.S. [National Cancer Institute, Division of Cancer Treatment and Diagnosis, Radiation Research Program, 6130 Executive Blvd., MSC 7440, Bethesda, MD 20892-7440 (United States)

    2011-09-15

    Biological dosimetry is an essential tool for estimating radiation doses received to personnel when physical dosimetry is not available or inadequate. The current preferred biodosimetry method is based on the measurement of radiation-specific dicentric chromosomes in exposed individuals' peripheral blood lymphocytes. However, this method is labor-, time- and expertise-demanding. Consequently, for mass casualty applications, strategies have been developed to increase its throughput. One such strategy is to develop validated cytogenetic biodosimetry laboratory networks, both national and international. In a previous study, the dicentric chromosome assay (DCA) was validated in our cytogenetic biodosimetry network involving five geographically dispersed laboratories. A complementary strategy to further enhance the throughput of the DCA among inter-laboratory networks is to use a triage DCA where dose assessments are made by truncating the labor-demanding and time-consuming metaphase spread analysis to 20 - 50 metaphase spreads instead of routine 500 - 1000 metaphase spread analysis. Our laboratory network also validated this triage DCA, however, these dose estimates were made using calibration curves generated in each laboratory from the blood samples irradiated in a single laboratory. In an emergency situation, dose estimates made using pre-existing calibration curves which may vary according to radiation type and dose rate and therefore influence the assessed dose. Here, we analyze the effect of using a pre-existing calibration curve on assessed dose among our network laboratories. The dose estimates were made by analyzing 1000 metaphase spreads as well as triage quality scoring and compared to actual physical doses applied to the samples for validation. The dose estimates in the laboratory partners were in good agreement with the applied physical doses and determined to be adequate for guidance in the treatment of acute radiation syndrome.

  20. The use of the dicentric assay for biological dosimetry for radiation accidents in Bulgaria.

    Science.gov (United States)

    Hadjidekova, Valeria; Hristova, Rositsa; Ainsbury, Elizabeth A; Atanasova, Petya; Popova, Ljubomira; Staynova, Albena

    2010-02-01

    This paper details the construction of a 137Cs gamma calibration curve that has been established for dicentric assay and the testing and validation of the curve through biological dosimetry in three situations of suspected workplace overexposure that arose accidentally or through negligence or lack of appropriate safety measures. The three situations were: (1) suspected 137Cs contamination in a factory air supply; (2) suspected exposure to an industrial 192Ir source; and (3) accidental exposure of construction workers to radiation from a 60Co radiotherapy source in a hospital medical physics department. From a total of 24 potentially-exposed subjects, only one worker was found to have a statistically significant dose (0.16 Gy, 95% confidence intervals 0.02-0.43 Gy). In all other cases, the main function of the biological dosimetry was to reassure the subjects that any dose received was low.

  1. Radiation protection - Performance criteria for service laboratories performing biological dosimetry by cytogenetics

    International Nuclear Information System (INIS)

    2004-01-01

    This International Standard provides criteria for quality assurance and quality control, evaluation of the performance and the accreditation of biological dosimetry by cytogenetic service laboratories. This International Standard addresses: a) the confidentiality of personal information, for the customer and the service laboratory, b) the laboratory safety requirements, c) the calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels, d) the scoring procedure for unstable chromosome aberrations used for biological dosimetry, e) the criteria for converting a measured aberration frequency into an estimate of absorbed dose, f) the reporting of results, g) the quality assurance and quality control, h) informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations and a sample report

  2. Dosimetry in support of wholesomeness studies

    International Nuclear Information System (INIS)

    Jarrett, R.D.; Halliday, J.W.

    1979-01-01

    Interest in dosimetry procedures in the context of a large-scale processing situation exceeds the purely documentary aspects of this report. The numerous combinations afforded by the various types, strengths and configurations of irradiation sources and the possibilities for various conveyors and other facility design factors impacting on irradiation logistics render a completely general treatment of dosimetry procedures in such instances almost impossible. While the exact combination of these various factors represented by the irradiation facilities at NARADCOM may be duplicated nowhere else, the dosimetry procedures documented in this report offer both experience and solutions that might be more generally useful. Therefore, this report complements and supplements more general discussions found in the literature and cited in the text

  3. Mammalian spermatogenesis as a new system for biologic dosimetry of ionizing irradiation

    International Nuclear Information System (INIS)

    Hacker, U.; Schumann, J.; Goehde, W.

    1982-01-01

    The radiation induced reduction of the number of DNA synthesizing cells (spermatogonia) is described using the fast-working flow cytophotometer. Since there is no shoulder in the initial part of the dose response curve this model of biologic dosimetry is very sensitive. The D 50 value is 0.25 Gy; a radiation exposure of only 0.1 Gy can be detected. (Auth.)

  4. The Latin American Biological Dosimetry Network (LBDNet): Argentina, Brazil, Chile, Cuba, Mexico, Peru, Uruguay

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Arceo M, C. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Di Giorgio, M.; Vallerga, M.; Radl, A. [Autoridad Regulatoria Nuclear, Av. del Libertador 8250, C1429 BNP CABA (Argentina); Taja, M.; Seoane, A.; De Luca, J. [Universidad Nacionald de La Plata, Av. 7 No. 1776, La Plata 1900, Buenos Aires (Argentina); Stuck O, M. [Instituto de Radioproteccion y Dosimetria, Av. Salvador Allende s/n, Recreio dos Bandeirantes, Rio de Janeiro (Brazil); Valdivia, P., E-mail: lbdnet@googlegroups.co [Comision Chilena de Energia, Amutanegui 95, Santiago Centro, Santiago (Chile)

    2010-10-15

    Biological dosimetry is a necessary support for national radiation protection programs and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 for mutual assistance in case of radiation emergencies and for providing support to other Latin American countries that do not have bio dosimetry laboratories. In the frame of the IAEA Technical Cooperation Projects RLA/9/54 and RLA/9/61 the following activities have been performed: a) An international intercomparison exercise organized during 2007-2008 included six European countries and LBDNet laboratories. Relevant parameters related with dose assessment were evaluated through triage and conventional scoring criteria. A new approach for statistical data analysis was developed including assessment of inter-laboratory reproducibility and intra-laboratory repeatability. Overall, the laboratory performance was satisfactory for mutual cooperation purposes. b) In 2009, LBDNet and two European countries carried out a digital image intercomparison exercise involving dose assessment from metaphase images distributed electronically through internet. The main objectives were to evaluate scoring feasibility on metaphase images and time response. In addition a re-examination phase was considered in which the most controversial images were discussed jointly, this allowed for the development of a homogeneous scoring criteria within the network. c) A further exercise was performed during 2009 involving the shipment of biological samples for biological dosimetry assessment. The aim of this exercise was to test the timely and properly sending and receiving blood samples under national and international regulations. A total of 14 laboratories participated in this joint IAEA, PAHO and WHO. (Author)

  5. The Latin American Biological Dosimetry Network (LBDNet): Argentina, Brazil, Chile, Cuba, Mexico, Peru, Uruguay

    International Nuclear Information System (INIS)

    Guerrero C, C.; Arceo M, C.; Di Giorgio, M.; Vallerga, M.; Radl, A.; Taja, M.; Seoane, A.; De Luca, J.; Stuck O, M.; Valdivia, P.

    2010-10-01

    Biological dosimetry is a necessary support for national radiation protection programs and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 for mutual assistance in case of radiation emergencies and for providing support to other Latin American countries that do not have bio dosimetry laboratories. In the frame of the IAEA Technical Cooperation Projects RLA/9/54 and RLA/9/61 the following activities have been performed: a) An international intercomparison exercise organized during 2007-2008 included six European countries and LBDNet laboratories. Relevant parameters related with dose assessment were evaluated through triage and conventional scoring criteria. A new approach for statistical data analysis was developed including assessment of inter-laboratory reproducibility and intra-laboratory repeatability. Overall, the laboratory performance was satisfactory for mutual cooperation purposes. b) In 2009, LBDNet and two European countries carried out a digital image intercomparison exercise involving dose assessment from metaphase images distributed electronically through internet. The main objectives were to evaluate scoring feasibility on metaphase images and time response. In addition a re-examination phase was considered in which the most controversial images were discussed jointly, this allowed for the development of a homogeneous scoring criteria within the network. c) A further exercise was performed during 2009 involving the shipment of biological samples for biological dosimetry assessment. The aim of this exercise was to test the timely and properly sending and receiving blood samples under national and international regulations. A total of 14 laboratories participated in this joint IAEA, PAHO and WHO. (Author)

  6. Main activities of the Latin American Network of Biological Dosimetry (LBDNet)

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Radl, A.; Taja, M.R.; Stuck Oliveira, M.; Valdivia, P.; Garcia Lima, O.; Lamadrid, A.; Gonzalez Mesa, J.E.; Romero Aguilera, I.; Mandina Cardoso, T.; Guerrero Carbajal, C.; Arceo Maldonado, C.; Espinoza, M.; Martinez Lopez, W.; Di Tomasso, M.; Barquinero, F.; Roy, L.

    2010-01-01

    The Latin American Biological Dosimetry Network (LBDNET) was constituted in 2007 for mutual assistance in case of a radiation emergency in the region supported by IAEA Technical Cooperation Projects RLA/9/054 and RLA/9/061. The main objectives are: a) to strengthen the technical capacities of Biological Dosimetry Services belonging to laboratories existing in the region (Argentine, Brazil, Chile, Cuba, Mexico, Peru and Uruguay) integrated in National Radiological Emergency Plans to provide a rapid biodosimetric response in a coordinated manner between countries and with RANET-IAEA/BioDoseNet-WHO, b) to provide support to other countries in the region lacking Biological Dosimetry laboratories, c) to consolidate the organization of the Latin American Biological Dosimetry Network for mutual assistance. The activities developed include technical meetings for protocols and chromosomal aberration scoring criteria unification, blood samples cultures exercises, chromosomal aberrations analysis at microscope, discussion of statistical methods and specialized software for dose calculation, the intercomparison between laboratory data after the analysis of slides with irradiated material and the intercomparison of the analysis of captured images distributed electronically in the WEB. The last exercise was the transportation of an irradiated human blood sample to countries inside and outside of the region. At the moment the exercises are concluded and they are pending to be published in reference journals. Results obtained show the capacity in the region for a biodosimetric response to a radiological accident. In the future the network will integrate techniques for high dose exposure evaluation and will enhance the interaction with other emergency systems in the region. (authors) [es

  7. Mammalian spermatogenesis as a new system for biologic dosimetry of ionizing irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, U; Schumann, J; Goehde, W [Muenster Univ. (Germany, F.R.). Radiologische Klinik

    1982-01-01

    The radiation induced reduction of the number of DNA synthesizing cells (spermatogonia) is described using the fast-working flow cytophotometer. Since there is no shoulder in the initial part of the dose response curve this model of biologic dosimetry is very sensitive. The D/sub 50/ value is 0.25 Gy; a radiation exposure of only 0.1 Gy can be detected.

  8. Biological dosimetry in patients with differenced thyroid carcinoma treated with Iodine-131

    International Nuclear Information System (INIS)

    Vallerga, M.; Taja, Maria R.; Radl, A.; Rojo, Ana M.; Deluca, G.; Di Giogio, Marina; Fadel, A.; Chebel, G.; Oneto, A.; Cabrejas, Mariana

    2007-01-01

    The differentiated thyroid carcinoma (DTC), constitutes the 90 % of the thyroid gland cancers. 80% of patients are cured after the initial therapy and 12% remained disease-free after successive treatments. The 24 patients included in this study represent a sample of the aforementioned 12% and 8%, with recurrence in the first decade post-treatment (local disease and/or recurrence at distance). The internal radiotherapy with 131 I in patients with DTC is used within the therapeutic schema as a step post-thyroidectomy. The success of the therapy is to get a lethal dose in the tumor tissue, which depends on the therapeutic activity and the retention of 131 I, without exceeding the dose of tolerance in healthy tissues. The most widespread way of administration is the empirical prescription which considers the clinical and laboratory parameters for its determination. In this work, the treatment protocol applied incorporates assessment by biological (DB) and internal (DI) dosimetry for estimating absorbed dose to the whole body and bone marrow to manage a personalized therapeutic dose for each patient. The biological dose estimation is based on the quantification of chromosomal aberrations, which is often referred to a dose-response curve in which lymphocytes are irradiated in vitro with 131 I, allowing to determine the dose in vivo of circulating lymphocytes patients [es

  9. Use of FISH-translocations analyses for retrospective biological dosimetry: How stable are stable chromosome aberrations?

    International Nuclear Information System (INIS)

    Darroudi, F.

    2000-01-01

    Chromosome aberrations, in particular dicentrics, in peripheral blood lymphocytes are used to estimate the absorbed dose immediately following a radiation accident. However, difficulties for dose estimation arise with old exposures, due to a decline of cells containing unstable dicentric aberrations. The fluorescence in situ hybridisation (FISH) technique employing chromosome specific DNA libraries to 'paint' individual human chromosomes has opened new perspectives for rapid and reliable detection of stable chromosome aberrations such as translocations. The inherent stability of translocations over cell generations has enabled them to be used as a biodosemeter. However, due to the limited life of circulating T-lymphocytes, a level of uncertainty exists on the long-term persistence of stable translocations. The objectives of the present work are to present the current state of knowledge on the stability of translocations detected by FISH. The following aspects have been considered; (1) experience so far of retrospective biological dosimetry in humans following accidental and occupational over-exposure, (2) animal studies using mice and monkeys, (3) the influence of subsequent cell divisions on the yield and persistence of translocations following in vitro irradiation of human lymphocytes, and (4) the needs for further work to standardise and validate the use of FISH as a biological dosemeter, and to investigate the influence of various parameters such as radiation quality, dose rate and the discrimination of sub-types of translocations on persistence. (author)

  10. A preliminary study on thermoluminescence of AMOLED glass from mobile phones for retrospective dosimetry

    International Nuclear Information System (INIS)

    Kim, Hyoungtaek; Lee, Jungil; Chang, Insu; Lee, Seung Kyu; Kim, Min Chae; Park, Sang Won; Kim, Jang-Lyul; Kim, Bong-Hwan; Yu, Hyungjoon; Kim, Ah-reum

    2017-01-01

    Since mobile phones are always carried by individuals, the retrospective dosimetry using thermoluminescence (TL) and optically stimulated luminescence (OSL) characteristics of elements in mobile phone is intensively developing nowadays due to its advantages over conventional biological dosimetry techniques. Using a TL and OSL method on resistors and inductors in a mobile phone, a low background dose (zero dose) about tens of mGy is acquired in previous study. Radiation workers have to wear a dosimeter to assess individual exposure during their works. This monitoring system facilitate a fast medical treatment for highly exposed workers in case of a radiation accident. In the event of large-scale radiation accidents, where most of the subjects are ordinary people, it is difficult to evaluate the individual dose due to the absence of dosimeters. A technique for dose evaluation using a radiation dependency of various materials in the absence of a dosimeter is called retrospective dosimetry.

  11. Tenth ORNL Personnel Dosimetry Intercomparison Study

    International Nuclear Information System (INIS)

    Swaja, R.E.; Chou, T.L.; Sims, C.S.; Greene, R.T.

    1985-03-01

    The Tenth Personnel Dosimetry Intercomparison Study was conducted at the Oak Ridge National Laboratory during April 9-11, 1984. Dosemeter badges from 31 participating organizations were mounted on 40cm Lucite phantoms and exposed to a range of dose equivalents which could be encountered during routine personnel monitoring in mixed radiation fields. The Health Physics Research Reactor served as the only source of radiation for eight of the ten irradiations which included a low (approx. 0.50 mSv) and high (approx. 10.00 mSv) neutron dose equivalent run for each of four shield conditions. Two irradiations were also conducted for which concrete- and Lucite-shield reactor irradiations were gamma-enhanced using a 137 Cs source. Results indicated that some participants had difficulty obtaining measurable indication of neutron and gamma exposures at dose equivalents less than about 0.50 mSv and 0.20 mSv, respectively. Albedo dosemeters provided the best overall accuracy and precision for the neutron measurements. Direct interaction TLD systems showed significant variation in accuracy with incident spectrum, and threshold neutron dosemeters (film and recoil track) underestimated reference values by more than 50%. Gamma dose equivalents estimated in the mixed fields were higher than reference values with TL gamma dosemeters generally yielding more accurate results than film. Under the conditions of this study in which participants had information concerning exposure conditions and radiation field characteristics prior to dosemeter evaluation, only slightly more than half of all reported results met regulatory standards for neutron and gamma accuracy. 19 refs., 2 figs., 29 tabs

  12. General guidelines for safe and expeditious international transport of samples subjected to biological dosimetry assessment.

    Science.gov (United States)

    Di Giorgio, Marina; Radl, Analía; Taja, María R; Bubniak, Ruth; Deminge, Mayra; Sapienza, Carla; Vázquez, Marina; Baciu, Florian; Kenny, Pat

    2014-06-01

    It has been observed that victims of accidental overexposures show better chance of survival if they receive medical treatment early. The increased risk of scenarios involving mass casualties has stimulated the scientific community to develop tools that would help the medical doctors to treat victims. The biological dosimetry has become a routine test to estimate the dose, supplementing physical and clinical dosimetry. In case of radiation emergencies, in order to provide timely and effectively biological dosimetry assistance it is essential to guarantee an adequate transport of blood samples in principal, for providing support to countries that do not have biodosimetry laboratories. The objective of the present paper is to provide general guidelines, summarised in 10 points, for timely and proper receiving and sending of blood samples under National and International regulations, for safe and expeditious international transport. These guidelines cover the classification, packaging, marking, labelling, refrigeration and documentation requirements for the international shipping of blood samples and pellets, to provide assistance missions with a tool that would contribute with the preparedness for an effective biodosimetric response in cases of radiological or nuclear emergencies. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Role of accelerator mass spectrometry in biological dosimetry

    International Nuclear Information System (INIS)

    Felton, J.S.; Turteltaub, K.W.; Frantz, C.; Vogel, J.S.; Gledhill, B.L.

    1992-01-01

    Understanding risks from exposures to carcinogens and other chemicals depends upon measurement of their dose to target tissues and their reactivity with critical macromolecules. The authors have used AMS detection of radio-isotopes to assess doses and reactivities at low, environmentally relevant doses. Several biomedical investigations show the effectiveness of quantification of biologically important events at extremely high sensitivity with AMS. Specifically, they have measured the addition of environmental carcinogens such as 2-amino-3,8-dimethylimidazo[4,5-f]-quinoaxaline (MelQx), a chemical found in cooked food, to DNA at concentrations relevant to human exposure. Other low level detection problems in biology, such as immunoassay assessment of small environmental chemicals, is being developed with attomole sensitivity. AMS also aids the assessment of genotoxic risks from chemicals by quantifying the binding of labeled chemicals to DNA. The very toxic and potent carcinogen, tetrachlorodibenzo-p-dioxin (TCDD) was assessed for DNA binding, but no detectable radiocarbon-labeled TCDD was found associated with mouse liver DNA at less than systematically toxic levels. The data indicate that a mutation mechanism does not mediate TCDD carcinogenesis

  14. Development of radiological emergency preparedness and biological dosimetry technology

    Energy Technology Data Exchange (ETDEWEB)

    Han, Moon Hee; Kim, In Gyoo; Kim, Kook Chan; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil; Shim, Hae Won; Lee, Jeong Ho; Lee, Kang Suk

    1999-04-01

    Large-scale field tracer experiments have been conducted on Ulchin and Wolsung nuclear sites for the purpose of validating FADAS and of analyzing the environmental characteristics around the nuclear site. The most influential factor in atmospheric dispersion is the meteorological condition. During the experiment, meteorological data were measured on the release point and the selected positions among sampling points. Once radioactive materials are released to the atmosphere, members of public may be exposed through the environmental media such as air, soil and foods. Therefore, to protect the public, adequate countermeasures should be taken at due time for those exposure pathways. Both processes of justification and optimization are applied to a countermeasure simultaneously for decision-making. The work scope of biological research for the radiation protection had contained the search of biological microanalytic methods for the assessment of health effect by radiation and toxic agents, the standardization of human t-lymphocyte cell culture and polymerase chain reaction, T-cell clonal assay, and the quantification of mutation frequency in hypoxanthine (guanine) phosphoribosyl transferase (hprt) gene locus by single exposure or combined exposure. Especially, the polymerase chain reaction methods by usage of reverse transcriptase had been developed to analyze of gene product by {gamma} - radiation and chemical (pentachlorophenol) agent exposure, and investigate the point mutation in hprt gene locus of T-lymphocytes. (author)

  15. Development of radiological emergency preparedness and biological dosimetry technology

    International Nuclear Information System (INIS)

    Han, Moon Hee; Kim, In Gyoo; Kim, Kook Chan; Kim, Eun Han; Suh, Kyung Suk; Hwang, Won Tae; Choi, Young Gil; Shim, Hae Won; Lee, Jeong Ho; Lee, Kang Suk

    1999-04-01

    Large-scale field tracer experiments have been conducted on Ulchin and Wolsung nuclear sites for the purpose of validating FADAS and of analyzing the environmental characteristics around the nuclear site. The most influential factor in atmospheric dispersion is the meteorological condition. During the experiment, meteorological data were measured on the release point and the selected positions among sampling points. Once radioactive materials are released to the atmosphere, members of public may be exposed through the environmental media such as air, soil and foods. Therefore, to protect the public, adequate countermeasures should be taken at due time for those exposure pathways. Both processes of justification and optimization are applied to a countermeasure simultaneously for decision-making. The work scope of biological research for the radiation protection had contained the search of biological microanalytic methods for the assessment of health effect by radiation and toxic agents, the standardization of human t-lymphocyte cell culture and polymerase chain reaction, T-cell clonal assay, and the quantification of mutation frequency in hypoxanthine (guanine) phosphoribosyl transferase (hprt) gene locus by single exposure or combined exposure. Especially, the polymerase chain reaction methods by usage of reverse transcriptase had been developed to analyze of gene product by γ - radiation and chemical (pentachlorophenol) agent exposure, and investigate the point mutation in hprt gene locus of T-lymphocytes. (author)

  16. Development of radiation biological dosimetry and treatment of radiation-induced damaged tissue

    International Nuclear Information System (INIS)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil

    2000-04-01

    Util now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline(triage) to be able to be treated the victims as fast as possible. We established the apoptotic fragment assay, PCC, comet assay, and micronucleus assay which was the significant relationship between dose and cell damages to evaluate the irradiated dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with chromosome dosimetry and micronucleus assay

  17. Development of radiation biological dosimetry and treatment of radiation-induced damaged tissue

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil [and others

    2000-04-01

    Util now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline(triage) to be able to be treated the victims as fast as possible. We established the apoptotic fragment assay, PCC, comet assay, and micronucleus assay which was the significant relationship between dose and cell damages to evaluate the irradiated dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with chromosome dosimetry and micronucleus assay.

  18. Biological dosimetry, scopes and limitations; Dosimetria biologica, alcances y limitaciones

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [Departamento de Biologia, Instituto Nacional de Investigaciones Nucleares, C.P. 52045 Salazar, Estado de Mexico (Mexico)

    1999-07-01

    The analysis of the aberrations in chromosomes is an alternative to establish the exposure dose to the radiation, when the information provided by the traditional physical methods is insufficient. There are diverse causes by which it can reached to apply an alternative system, such is the case of exposures of another persons to the management of radiation sources, which not carry physical dosemeter. Contrary case is to the occupational exposure personnel (OEP), what must to utilize some system for determining the exposure dose, even so can be needed the case for more information. In any case, the cells from the affected person are the alternative without the biological system be overlap to the physical, it is complementary. (Author)

  19. Retrospective dosimetry using salted snacks and nuts: a feasibility study

    International Nuclear Information System (INIS)

    Christiansson, M.; Geber-Bergstrand, T.; Bernhardsson, C.; Mattsson, S.; Raeaef, C.L.

    2017-01-01

    The possibility of using ordinary household table salt for dosimetry is suggested by its high sensitivity to ionising radiation, which generates a readout of optically stimulated luminescence (OSL). However, to exploit this finding for retrospective human dosimetry, it would be needed to find salt in close proximity to the exposed individual. Finding salty snacks frequently tucked into handbags, backpacks or pockets seemed to be a possibility; these items therefore became the test materials of the present study. The aluminium or cardboard packages used to exclude the moisture that makes crisps and nuts go soft and stale also helps to retain the induced OSL signal. Therefore, different snacks, either their salt component alone or mixed with the snack, are exposed to ionising radiation and then were assessed for their dosimetric properties. The results indicate the feasibility of using some salty snacks for dosimetry, with a minimum detectable dose as low as 0.2 mGy (authors)

  20. A transferability study of the EPR-tooth-dosimetry technique

    International Nuclear Information System (INIS)

    Sholom, S.; Chumak, V.; Desrosiers, M.; Bouville, A.

    2006-01-01

    The transferability of a measurement protocol from one laboratory to another is an important feature of any mature, standardised protocol. The electron paramagnetic resonance (EPR)-tooth dosimetry technique that was developed in Scientific Center for Radiation Medicine, AMS (Ukraine) (SCRM) for routine dosimetry of Chernobyl liquidators has demonstrated consistent results in several inter-laboratory measurement comparisons. Transferability to the EPR dosimetry laboratory at the National Inst. of Standards and Technology (NIST) was examined. Several approaches were used to test the technique, including dose reconstruction of SCRM-NIST inter-comparison samples. The study has demonstrated full transferability of the technique and the possibility to reproduce results in a different laboratory environment. (authors)

  1. Chromosomal analysis and application of biological dosimetry in two cases of apparent over exposure

    International Nuclear Information System (INIS)

    Guerrero C, C.; Brena V, M.

    2002-01-01

    The gamma radiation calibration curve of 60 Co is used which was generated in the ININ Laboratory of Biology to calculate the exposure dose of two workers whose dosemeters marked values above of the limit allowed. The analysis indicates that in a first case, the aberrations frequency corresponded to the basal value, therefore there is not over exposure. The aberrations frequency of the second case is lightly above to the basal value and therefore the probability favors to what the physical dosimetry indicates. (Author)

  2. Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988

    Energy Technology Data Exchange (ETDEWEB)

    Straume, T.; Ricker, Y.; Thut, M.

    1988-08-29

    This database was constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on publication number, authors, key words, title, year, and journal name. Photocopies of all publications contained in the database are maintained in a file that is numerically arranged by citation number. This report of the database is provided as a useful reference and overview. It should be emphasized that the database will grow as new citations are added to it. With that in mind, we arranged this report in order of ascending citation number so that follow-up reports will simply extend this document. The database cite 1212 publications. Publications are from 119 different scientific journals, 27 of these journals are cited at least 5 times. It also contains reference to 42 books and published symposia, and 129 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed among the scientific literature, although a few journals clearly dominate. The four journals publishing the largest number of relevant papers are Health Physics, Mutation Research, Radiation Research, and International Journal of Radiation Biology. Publications in Health Physics make up almost 10% of the current database.

  3. Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988

    International Nuclear Information System (INIS)

    Straume, T.; Ricker, Y.; Thut, M.

    1988-01-01

    This database was constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on publication number, authors, key words, title, year, and journal name. Photocopies of all publications contained in the database are maintained in a file that is numerically arranged by citation number. This report of the database is provided as a useful reference and overview. It should be emphasized that the database will grow as new citations are added to it. With that in mind, we arranged this report in order of ascending citation number so that follow-up reports will simply extend this document. The database cite 1212 publications. Publications are from 119 different scientific journals, 27 of these journals are cited at least 5 times. It also contains reference to 42 books and published symposia, and 129 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed among the scientific literature, although a few journals clearly dominate. The four journals publishing the largest number of relevant papers are Health Physics, Mutation Research, Radiation Research, and International Journal of Radiation Biology. Publications in Health Physics make up almost 10% of the current database

  4. Physical and biological dosimetries of Cf-252 radiation

    International Nuclear Information System (INIS)

    Yamashita, Hisao; Wada, Tadashi; Dokiya, Takushi; Hashimoto, Shozo

    1986-01-01

    Recently Cf-252 sources containing 300 μg have become available in a size identical to 1 Ci of Cs-137 and with the use of remotely controlled afterloading apparatus, safe therapy with little exposure to the therapist is now possible. Radiation leakage from the Cf-252 apparatus and from the treatment room was measured with REM-meter and it was possible to reduce the leakage from the treatment room to less than 1 mrem/h (gamma rays) and 0.5 mrem/h (neutrons). Measurement of fast neutrons was made with a twin chamber composed of a tissue equivalent ionization chamber and a carbon ionization chamber. The neutron dose in air and the absorbed dose in tissue equivalent water tank were measured, which showed that in air, neutrons were 70% and photons were 30% of dose. In water, greater distances from the source, neutrons attenuate and gamma rays increase in dose. The results of studies on the skin reaction of mice and sperm cleavage delay time of sea urchins indicated that the RBE ranges from 1.5 to 3.0 using the high dose rate system. Neutrons are remarkably affected by a time factor. With the use of high dose rate sources, the dose rate has become higher, but the overall time has been extended through dose fractionation and it was considered advisable to employ an RBE of 3-4 in these studies. (Auth.)

  5. Emergency preparedness exercise for biological dosimetry - BIOPEX (2008)

    Energy Technology Data Exchange (ETDEWEB)

    Lindholm, C.; Paile, W. (Radiation and Nuclear Safety Authority (STUK) (Finland)); Stricklin, D. (Swedish Defence Research Agency (FOI) (Sweden)); Jaworska, A. (Norwegian Radiation Protection Authority (NRPA) (Norway))

    2009-03-15

    As a continuation to the NKS-funded BIODOS project, the BIOPEX project has aimed at testing and validation of the newly established dose calibration curve for PCC rings, a specific chromosome aberration for use in biodosimetry in large casualty emergency preparedness. The testing of the PCC ring technique was performed by direct comparison to the conventional dicentric assay, both conducted with a triage approach that gives a crude dose estimate through analysis of a relatively small number of cells. Altogether 62 blood samples were analysed, each irradiated with an individual dose using gamma-rays, and representing casualties in a simulated radiation accident resulting in a broad spectrum of whole body and partial body doses, ranging from zero dose up to a lethal whole body dose of 13 Gy. The results indicated that both triage assays were capable of discerning non-exposed cases and that in the uniform irradiations, the dose estimates based on data from both assays were fairly consistent with the given dose. However, differences were observed depending on the dose level. At doses about 5 Gy and below, dicentric scoring resulted in more accurate whole-body dose estimates than PCC rings. At very high doses, PCC rings appeared to give more accurate dose estimates than dicentrics. The discrepancies are mainly caused by shortcomings in the respective dose calibration curves. In non-uniform irradiations, the PCC ring assay was slightly better in the approximation of the partial body dose than dicentrics, but neither assay enabled accurate estimation of either dose or fraction of cells irradiated. The irradiated fraction of cells for the casualties in this scenario was apparently too small (10-40%) to be distinguished with the triage approach applied in the current study. With respect to the technical aspects, scoring of the PCC rings is easier and therefore somewhat faster but may be more sensitive to quality aspects. In conclusion, the study demonstrated that the PCC

  6. Study of the personal dosimetry service by thermoluminiscence

    International Nuclear Information System (INIS)

    Penaherrera, Patricio; Buitron, Susana; Prado, Elizabeth; Ceron Fabiola

    1992-01-01

    This paper is concerned with the personal dosimetry service given by the Ecuadorian Atomic Energy Commission to radiation exposed workers in Ecuador. The study has taken in consideration the number of professionals working in Ecuador by province and by area of work, and also the radiation doses received by them during the period 1987-1990

  7. Extension of the biological effective dose to the MIRD schema and possible implications in radionuclide therapy dosimetry

    International Nuclear Information System (INIS)

    Baechler, Sebastien; Hobbs, Robert F.; Prideaux, Andrew R.; Wahl, Richard L.; Sgouros, George

    2008-01-01

    In dosimetry-based treatment planning protocols, patients with rapid clearance of the radiopharmaceutical require a larger amount of initial activity than those with slow clearance to match the absorbed dose to the critical organ. As a result, the dose-rate to the critical organ is higher in patients with rapid clearance and may cause unexpected toxicity compared to patients with slow clearance. In order to account for the biological impact of different dose-rates, radiobiological modeling is beginning to be applied to the analysis of radionuclide therapy patient data. To date, the formalism used for these analyses is based on kinetics derived from activity in a single organ, the target. This does not include the influence of other source organs to the dose and dose-rate to the target organ. As a result, only self-dose irradiation in the target organ contributes to the dose-rate. In this work, the biological effective dose (BED) formalism has been extended to include the effect of multiple source organ contributions to the net dose-rate in a target organ. The generalized BED derivation has been based on the Medical Internal Radionuclide Dose Committee (MIRD) schema assuming multiple source organs following exponential effective clearance of the radionuclide. A BED-based approach to determine the largest safe dose to critical organs has also been developed. The extended BED formalism is applied to red marrow dosimetry, as well as kidney dosimetry considering the cortex and the medulla separately, since both those organs are commonly dose limiting in radionuclide therapy. The analysis shows that because the red marrow is an early responding tissue (high α/β), it is less susceptible to unexpected toxicity arising from rapid clearance of high levels of administered activity in the marrow or in the remainder of the body. In kidney dosimetry, the study demonstrates a complex interplay between clearance of activity in the cortex and the medulla, as well as the initial

  8. Calibration curves for biological dosimetry by drug-induced prematurely condensed chromosomes in human lymphocytes

    International Nuclear Information System (INIS)

    Kang, C. M.; Chung, H. C.; Cho, C. K.

    2002-01-01

    To develop the cytogenetic tool to detect chromosome damages after high dose exposure with 60 Coγ- rays, dose-response curves were measured for induction of prematurely condensed chromosomes (PCC) in peripheral lymphocytes. Blood was obtained from 10 different healthy donors, and given okadaic acid (OA) 500nM in cultured lymphocytes 1h after radiation exposure. Cells were analyzed by the frequencies of OA-induced PCC rings because it is difficult to obtain mitotic chromosomes using a conventional chromosome aberration (CA). PCC-rings were scored in cells exposed in the dose range of 0.2-16Gy. The frequency of the cells with PCC and the dose-response relationship for the yield of PCC rings were examined in the irradiated lymphocytes. The yield of PCC-rings increased with dose dependent-manner up to 16Gy. The observed dose-effect relationship for the percentage of cells with PCC-rings was calculated by linear-quadratic model. This technique can be applied to biological dosimetry of radiation exposures involving whole body irradiation to allow damaged chromosomes to be detected with great sensitivity. Detection of okadaic acid-induced PCC rings is a useful method up to 16Gy or more doses in estimating the absorbed doses of victims after high dose exposure. Calibration curves described in this paper will be used in our laboratory for biological dosimetry by PCC-ring after a high dose exposure

  9. Biological dosimetry of heavy ion induced chromosome lesions in human peripheral blood lymphocytes of different healthy donors

    International Nuclear Information System (INIS)

    Groesser, T.; Rydberg, B.; Ritter, S.; Hessel, P.; Kraft, G.

    2003-01-01

    Full text: In the presented work the effect of sparsely ionizing X-rays or densely ionizing carbon ions on human peripheral blood lymphocytes (PBL) from healthy donors regarding the fluctuations in radiosensitivity within the same donor and between different donors was examined. This is not only of special interest for physicians and radiation biologists but also plays an important role in space flights because such fluctuations in the radiation response would reduce the accuracy of the biological dosimetry. In this context, biological changes in the aberration rate of metaphase cells as well as in cell proliferation and the mitotic index were measured. Since chromosome analyses are presently the most powerful biological method to quantify radiation exposure, the study focused on the measurements of chromosome aberrations in first-metaphase cells. The investigations showed that the aberration yield after 400 MeV/u carbon ion exposure (LET = 11 keV/micrometer) was higher than after X-irradiation. The aberration yield in first mitotic cells as well as the proportion of damaged cells was stable over the examined period up to 72h after exposure to X-rays or carbon ions. Furthermore, the results of the presented work revealed pronounced fluctuations in the measured parameters in the same donor as well as between different donors. If the dose effect curves of such parameters were used as calibration curves for radiation dose assessment these fluctuations will decrease their potential of use for dose estimation. This demonstrates that a general calibration curve for dose assessment might not be sufficiently precise and individual calibration curves might improve the accuracy of the biological dosimetry

  10. Biological dosimetry in case of combined radiation injuries. Biologicheskaya dozimetriya pri kombinirovannykh radiatsionnykh porazheniyakh

    Energy Technology Data Exchange (ETDEWEB)

    Vladimirov, V G; Teslenko, V M

    1990-11-01

    The state of biological dosimetry methods and prospects for their development are considered. Attention is paid to biological indicators of radiation injuries caused by nuclear weapons. It is noted, that determination of the number of lymphocytes in the blood in case of combined radiation injuries should be concerned with great care and in each case the analysis results should reffered to critically and supported by the data from other investigations. Promissing are the methods related to dermination of reticulocyte number in the peripheral blood within the irradiation dose range, causing bone marrow form of radiation syndrome, method of leukocyte adhesion and some other methods based on the change of biophysical caracteristics of cell membranes. To increase the information efficiency it is necessary to combine these methods with the methods, based on genetic change registration, and to develop a combined method.

  11. Light scattering by irradiated cells as a method of biological dosimetry

    International Nuclear Information System (INIS)

    Ostashevsky, J.

    1984-01-01

    Light scattering (LS) parameters between 350-500 nm wavelength have been studied for 2 groups of cells: 1) blood (BL) and thymus (TL) lymphocytes of rats and mice, and 2) Ehrlich ascite tumor (EAT) cells. LS measurements of freshly prepared cell suspensions have been made 24 hrs after x-ray irradiation of rodents (250 Kev, HVL = 2 mm Cu) at doses of 50-900 cGy. A steep (30% per Gy) linear (50-800 cGy for TL and 50-400 cGy for BL) dose-dependence was obtained for the increase in 90 0 -angle LS intensity. Increase in absorption (low-angle LS) was also linear (50-800 cGy for TL and BL) but less steep (9% per Gy). Irradiated cells were the same size as unirradiated. Changes in LS for TL and BL appear to follow the appearance of additional vacuoles which may become new internal smaller-size centers of LS. This suggestion is supported by direct observations of cells with dark-field microscopy. For EAT cells, both 90 0 and low angle LS had the same slope. This slope (4% per Gy) is much shallower than that for BL and TL, and quantitatively coincides with enlargement of area of EAT cells, which could explain LS changes. The difference in LS behavior of the two cellular groups reflects a difference in their early response to irradiation: interphase death for TL and BL, vs division delay for EAT cells. The above data suggest the fast and simple method of biological dosimetry

  12. Bibliographical database of radiation biological dosimetry and risk assessment: Part 2

    International Nuclear Information System (INIS)

    Straume, T.; Ricker, Y.; Thut, M.

    1990-09-01

    This is part 11 of a database constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on authors, key words, title, year, journal name, or publication number. Photocopies of the publications contained in the database are maintained in a file that is numerically arranged by our publication acquisition numbers. This volume contains 1048 additional entries, which are listed in alphabetical order by author. The computer software used for the database is a simple but sophisticated relational database program that permits quick information access, high flexibility, and the creation of customized reports. This program is inexpensive and is commercially available for the Macintosh and the IBM PC. Although the database entries were made using a Macintosh computer, we have the capability to convert the files into the IBM PC version. As of this date, the database cites 2260 publications. Citations in the database are from 200 different scientific journals. There are also references to 80 books and published symposia, and 158 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed within the scientific literature, although a few journals clearly predominate. The journals publishing the largest number of relevant papers are Health Physics, with a total of 242 citations in the database, and Mutation Research, with 185 citations. Other journals with over 100 citations in the database, are Radiation Research, with 136, and International Journal of Radiation Biology, with 132

  13. Biological dosimetry after criticality accidents. Intercomparison exercise in the Silene Reactor - France

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Taja, Maria R.

    2004-01-01

    The Institute of Radiation Protection and Nuclear Safety Institute (IRSN) organized an international biological dosimetry intercomparison, at the SILENE experimental reactor (Valduc, France), simulating different criticality scenarios: bare source 4 Gy, lead shield source 1 and 2 Gy and gamma pure 60 Co source 2 Gy. Fifteen laboratories were involved in this exercise, including the Argentine Biological Dosimetry Laboratory. The purposes of the intercomparison were: 1) To compare the unstable chromosome aberration (UCA) frequency observed by the different laboratories; and 2) To compare the dose estimation for gamma rays and neutrons. The objects of the present work were: I) To compare the mean frequency of UCA observed by the Argentine laboratory with the mean frequency observed by the participant laboratories as a whole. II) To compare the dose estimates performed by the Argentine lab with those estimated by the other laboratories involved in the second stage of the intercomparison. Overall, the mean frequencies of UCA and the correspondent 95% confidence limits obtained by the Argentine lab were consistent with the results obtained by the laboratories as a whole. For the gamma pure scenario, smaller variations were observed among laboratories in terms of dose (CV=18,2%) than in terms of frequency (CV=30,1%). For the mixed field scenarios, only four laboratories, including the Argentine lab, estimated gamma and neutron components of the total dose and just two (Argentine lab and lab 12) were in agreement with the given physical doses. The 1 Gy experiment presented lesser variations both in terms of frequency and dose than the other two scenarios. For the 4 and 2 Gy experiments, variations in neutron dose were more significant than variations in gamma dose, related to the magnitude of the dose. The results suggest that intercomparison exercises jointly with the accreditation of biological dosimetry by cytogenetic service laboratories, in compliance with ISO

  14. Biological dosimetry of patients with differenced carcinoma of thyroid treated with Iodine-131

    International Nuclear Information System (INIS)

    Vallerga, M. B.; Rojo, A.M.; Taja, M.R.; Deluca, G.; Di Giorgio, M.; Fadel, A.; Cabrejas, M.; Valdivieso, C.

    2006-01-01

    The administration of I-131 to patient with Differentiated Thyroid Carcinoma (CaDiT) it is used inside the therapeutic outline as later step to the thyroidectomy. However, the good activity to give is of difficult determination due to factors such as, the variability in the capacity of tumoral reception of the I-131, distribution of the pharmaceutical, physiologic status, other associate pathologies, grade of advance of the illness, and previous treatments. Additionally, the activity to administer is dependent of the dose of tolerance in the healthy tissues; superior dose to 2 Gy in bone marrow, its could drive to myelotoxicity. At the moment, the form more extended of administration it is the empiric prescription that considers clinical parameters and of laboratory for their determination. Presently work, the protocol of applied treatment incorporates the evaluation for internal dosimetry and biological dosimetry to estimate absorbed dose in bone marrow. The biological estimate of the dose of these patients is based on the quantification of chromosomal aberrations whose frequency is referred to a curve-dose response in which the lymphocytes is irradiated in vitro with I-131, allowing to determine the in vivo dose to the patient's circulating lymphocytes. The objective of the present work is to determine the applicability of different cytogenetic essays in the estimate of the absorbed dose to the whole body or specific organs. Three patients were evaluated with CaDiT. Their treatment protocol consisted on a tracer administration of radioactive iodine of 74 - 111 MBq (2 - 3 mCi) and a therapy 7,4 - 11,1 GBq (200 - 300 mCi). Previous to the tracer administration and 8 days post-therapeutic administration took samples of veined blood that were evaluated by biological dosimetry by means of the application of the techniques: conventional cytogenetic Micronucleus and FISH (Hybridization in situ by Fluorescence). Starting from the frequencies of observed chromosomal

  15. In-situ fluorescence hybridization applied to biological dosimetry: contribution of automation to the counting of radio-induced chromosome aberrations

    International Nuclear Information System (INIS)

    Germain Thomas Roy, Laurence

    1999-01-01

    The frequency of chromosome aberrations on peripheral blood lymphocytes is a dose indicator in the case of ionizing radiations over-exposure. Stable chromosome aberrations (translocations, insertions) are visualized after labelling of some chromosomes using the fluorescence in-situ hybridization (FISH). The study of the use of the FISH technique in biological dosimetry is done with dose-effect curves. It seems that a bias is introduced during the observation of chromosome aberrations involving only 3 pairs of chromosomes. In order to avoid this bias, it would be useful to test the feasibility of using the multi-FISH technique in biological dosimetry. Moreover, this type of chromosome aberration changes with the type of irradiation. It is thus important to define the aberrations to be considered when the FISH technique is used. In order to reduce the time of image analysis, the CYTOGEN system, developed by IMSTAR company (Paris, France) has been adapted to the needs of biological dosimetry. This system allows to localize automatically the metaphases on the slide, which reduces the observation time by 2 or 4. An automatic detection protocol for chromosome aberrations has been implemented. It comprises the image capture, the contours detection and the classification of some chromosome aberrations. The different steps of this protocol have been tested in order to check that no bias is introduced by the automation. However, because radio-induced aberrations are rare events, it seems that a totally automatic system is not foreseeable. A semi-automatic analysis is more suitable. The use of the Slit-Scan technology (Laboratory of applied physics, Heidelberg, Germany) in biological dosimetry has been studied too. This technique allows to analyze rapidly a huge number of chromosomes. A good correlation has been observed between the dicentric frequency measured automatically and by manual counting. The system is under development and should be adapted to the detection of

  16. Biological dosimetry in cases gives occupational high exposition to ionizing radiations

    International Nuclear Information System (INIS)

    Ramalho, Adriana T.; Costa, Maria Lucia P.; Oliveira, Monica S.; Silva, Francisco Cesar A.

    1998-01-01

    From 1983 the cytogenetics dosimetry method it has been used as routine in the IRD laboratory in the period 1983 at 1997 but a high exposition occupational case the physical dosimeters happened in Brazil they were investigated through the cytogenetics dosimetry technique. This technique is employ when the dosimetry personal marks a high dose to 100 mSv (0,1 Gy) that is the cut-off minimum detected in the dosimetry cytogenetics

  17. Calibration curves for biological dosimetry; Curvas de calibracion para dosimetria biologica

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail cgc@nuclear.inin.mx

    2004-07-01

    The generated information by the investigations in different laboratories of the world, included the ININ, in which settles down that certain class of chromosomal leisure it increases in function of the dose and radiation type, has given by result the obtaining of calibrated curves that are applied in the well-known technique as biological dosimetry. In this work is presented a summary of the work made in the laboratory that includes the calibrated curves for gamma radiation of {sup 60} Cobalt and X rays of 250 k Vp, examples of presumed exposure to ionizing radiation, resolved by means of aberration analysis and the corresponding dose estimate through the equations of the respective curves and finally a comparison among the dose calculations in those people affected by the accident of Ciudad Juarez, carried out by the group of Oak Ridge, USA and those obtained in this laboratory. (Author)

  18. Application of TL dosimetry in epidemiological studies in HBRAs

    International Nuclear Information System (INIS)

    Chougaonkar, M.P.

    2006-01-01

    Luminescence as a phenomenon has been extensively used in radiation dosimetry, using thermoluminescence. The nuclear industry all over the world over uses TL dosimetry in radiation protection since they have to ensure that the radiation workers and workers involved in industrial applications of radiation sources are not exposed beyond limits set by international monitoring bodies. They have also to ensure that the nuclear applications do not give rise to elevated radiation levels in the environs. In addition, epidemiologists and radiobiologists world over have been working over the past few decades, to study health effects of chronic radiation exposures in populations living in the elevated natural radiation environment. This paper discusses the importance of dosimetric studies, in the normal as well as high background radiation areas (HBRAs), due to the radiation effects on the humans. The application of thermoluminescent dosimeters (TLDs) in population dosimetry with the end point of epidemiological studies is then discussed. The paper outlines the construction of TLDs, methodology of deployment and retrieval and analysis to arrive the dose. To obtain total dose, dosimetric techniques suitable for external gamma radiation, inhalation dose due to radon, thoron and their progenies and radiological analysis of the food items is required. The techniques arriving at the effective dose are outlined. Basics of epidemiological analysis, particularly using case-control methodology and its advantages/ disadvantages are also discussed. Using the previous work by the author, the paper also reviews various analyses that can be carried out the dosimetric data. (author)

  19. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO

    International Nuclear Information System (INIS)

    Cucinotta, F.A.; Wilson, J.W.; Williams, J.R.; Dicello, J.F.

    2000-01-01

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/μm. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm 2 of material is used

  20. Biological dosimetry intercomparison exercise: an evaluation of Triage and routine mode results by robust methods

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Radl, A.; Taja, M.R.; Barquinero, J.F.; Seoane, A.; De Luca, J.; Guerrero Carvajal, Y.C.; Stuck Oliveira, M.S.; Valdivia, P.; García Lima, O.; Lamadrid, A.; González Mesa, J.; Romero Aguilera, I.; Mandina Cardoso, T.; Arceo Maldonado, C.; Espinoza, M.E.; Martínez López, W.; Lloyd, D.C.; Méndez Acuña, L.; Di Tomaso, M.V.; Roy, L.; Lindholm, C.; Romm, H.; Güçlü, I.

    2011-01-01

    Well-defined protocols and quality management standards are indispensable for biological dosimetry laboratories. Participation in periodic proficiency testing by interlaboratory comparisons is also required. This harmonization is essential if a cooperative network is used to respond to a mass casualty event. Here we present an international intercomparison based on dicentric chromosome analysis for dose assessment performed in the framework of the IAEA Regional Latin American RLA/9/054 Project. The exercise involved 14 laboratories, 8 from Latin America and 6 from Europe. The performance of each laboratory and the reproducibility of the exercise were evaluated using robust methods described in ISO standards. The study was based on the analysis of slides from samples irradiated with 0.75 (DI) and 2.5 Gy (DII). Laboratories were required to score the frequency of dicentrics and convert them to estimated doses, using their own dose-effect curves, after the analysis of 50 or 100 cells (triage mode) and after conventional scoring of 500 cells or 100 dicentrics. In the conventional scoring, at both doses, all reported frequencies were considered as satisfactory, and two reported doses were considered as questionable. The analysis of the data dispersion among the dicentric frequencies and among doses indicated a better reproducibility for estimated doses (15.6% for DI and 8.8% for DII) than for frequencies (24.4% for DI and 11.4% for DII), expressed by the coefficient of variation. In the two triage modes, although robust analysis classified some reported frequencies or doses as unsatisfactory or questionable, all estimated doses were in agreement with the accepted error of ±0.5 Gy. However, at the DI dose and for 50 scored cells, 5 out of the 14 reported confidence intervals that included zero dose and could be interpreted as false negatives. This improved with 100 cells, where only one confidence interval included zero dose. At the DII dose, all estimations fell within

  1. Patient dosimetry study of a paediatric CT examination

    International Nuclear Information System (INIS)

    Hranitzky, C.; Stadtmann, H.

    2011-01-01

    Dosimetry studies are of increasing interest in diagnostic high-dose applications such as computed tomography especially for examinations of children. A routine CT scan protocol for paediatric head and neck imaging was investigated at a new multi-detector CT scanner using LiF:Mg,Cu,P thermoluminescence dosemeters (TLDs) and a 0.125 cm 3 thimble ionization chamber. Calibrations of the detectors in terms of absorbed dose to water were carried out at the Dosimetry Laboratory Seibersdorf in standard radiation fields. The dosimetry method was validated in the spiral CT X-ray field by comparing TLD and ionization chamber measurement results in cylindrical PMMA phantoms. Absorbed dose results were within stated uncertainties. An anthropomorphic phantom representing a child of about 5 years was loaded with TLD chips at various organ and tissue positions in the head and neck region as well as at some critical organ locations. Organ dose values were calculated from TLD based average absorbed dose with about 5% total uncertainty, e.g. 22 mGy (eyes), 21 mGy (thyroid), 19 mGy (brain), 3.4 mGy (thymus), and 0.03 mGy (testes). For comparison purposes an effective dose of 1.9 mSv was estimated for the investigated paediatric CT examination based on ICRP-103 age-independent tissue-weighting factors.

  2. Study of a 3D dosimetry system response: ARCCHECK®

    Energy Technology Data Exchange (ETDEWEB)

    Mazer, Amanda C.; Yoriyaz, Hélio, E-mail: amandamazer18@gmail.com, E-mail: hyoriyaz@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil); Nakandakari, Marcos V.N., E-mail: marcos.sake@gmail.com [Beneficência Portuguesa de São Paulo, SP (Brazil)

    2017-07-01

    Ionizing radiation therapies have improved over the years, becoming more specific for each patient. Thereby as the treatment planning system (TPS) complexities increases, the quality assurance (QA) methods have to be in a constant evolution. One of the techniques that demand great complexity is the Volumetric Modulated Arc Therapy (VMAT). One possible way to VMAT commissioning is using 3D dosimetry systems and recently a new 3D dosimetry system called ArcCheck had been developed and commercialized mainly for VMAT quality assurance. It is water-equivalent and composed by an array of 1386 diodes arranged in a spiral pattern. Since simulation methods, like Monte Carlo method, ensure highly accurate results, MCNP (A General Monte Carlo N-Particle Transport Code System) is totally reliable for problems that involve radiation transport. This work presents a preliminary study of the 3D dosimetry system ArcCheck by developing two computational models in MCNP6. In addition, experimental measures were acquired using the ArcCheck in a Linear Accelerator and then these values were compared with the results obtained by simulations of both models. The comparisons showed good reproducibility. (author)

  3. Biological dosimetry in radiological protection: dose response curves elaboration for 60Co and 137Cs

    International Nuclear Information System (INIS)

    Silva, Marcia Augusta da

    1997-01-01

    Ionizing radiation sources for pacific uses are being extensively utilized by modern society and the applications of these sources have raised the probability of the occurrence of accidents. The accidental exposition to radiation creates a necessity of the development of methods to evaluate dose quantity. This data could be obtained by the measurement of damage caused by radiation in the exposed person. The radiation dose can be estimated in exposed persons through physical methods (physical dosimetry) but the biological methods can't be dispensed, and among them, the cytogenetic one that makes use of chromosome aberrations (dicentric and centric ring) formed in peripheral blood lymphocytes (PBL) exposed to ionizing radiation. This method correlates the frequency of radioinduced aberrations with the estimated absorbed dose, as in vitro as in vivo, which is called cytogenetic dosimetry. By the introduction of improved new techniques in culture, in the interpretation of aberrations in the different analysers of slides and by the adoption of different statistical programs to analyse the data, significant differences are observed among laboratories in dose-response curves (calibration curves). The estimation of absorbed dose utilizing other laboratory calibration curves may introduce some uncertainties, so the International Atomic Energy Agency (IAEA) advises that each laboratory elaborates your own dose-response curve for cytogenetic dosimetry. The results were obtained from peripheral blood lymphocytes of the healthy and no-smoking donors exposed to 60 Co and 137 Cs radiation, with dose rate of 5 cGy.min. -1 . Six points of dose were determined 20,50,100,200,300,400 cGy and the control not irradiated. The analysed aberrations were of chromosomic type, dicentric and centric ring. The dose response curve for dicentrics were obtained by frequencies weighted in liner-quadratic mathematic model and the equation resulted were for 60 Co: Y = (3 46 +- 2.14)10 -4 cGy -1 + (3

  4. Hybrid 3D pregnant woman and fetus modeling from medical imaging for dosimetry studies

    Energy Technology Data Exchange (ETDEWEB)

    Bibin, Lazar; Anquez, Jeremie; Angelini, Elsa; Bloch, Isabelle [Telecom ParisTech, CNRS UMR 5141 LTCI, Institut TELECOM, Paris (France)

    2010-01-15

    Numerical simulations studying the interactions between radiations and biological tissues require the use of three-dimensional models of the human anatomy at various ages and in various positions. Several detailed and flexible models exist for adults and children and have been extensively used for dosimetry. On the other hand, progress of simulation studies focusing on pregnant women and the fetus have been limited by the fact that only a small number of models exist with rather coarse anatomical details and a poor representation of the anatomical variability of the fetus shape and its position over the entire gestation. In this paper, we propose a new computational framework to generate 3D hybrid models of pregnant women, composed of fetus shapes segmented from medical images and a generic maternal body envelope representing a synthetic woman scaled to the dimension of the uterus. The computational framework includes the following tasks: image segmentation, contour regularization, mesh-based surface reconstruction, and model integration. A series of models was created to represent pregnant women at different gestational stages and with the fetus in different positions, all including detailed tissues of the fetus and the utero-fetal unit, which play an important role in dosimetry. These models were anatomically validated by clinical obstetricians and radiologists who verified the accuracy and representativeness of the anatomical details, and the positioning of the fetus inside the maternal body. The computational framework enables the creation of detailed, realistic, and representative fetus models from medical images, directly exploitable for dosimetry simulations. (orig.)

  5. Hybrid 3D pregnant woman and fetus modeling from medical imaging for dosimetry studies

    International Nuclear Information System (INIS)

    Bibin, Lazar; Anquez, Jeremie; Angelini, Elsa; Bloch, Isabelle

    2010-01-01

    Numerical simulations studying the interactions between radiations and biological tissues require the use of three-dimensional models of the human anatomy at various ages and in various positions. Several detailed and flexible models exist for adults and children and have been extensively used for dosimetry. On the other hand, progress of simulation studies focusing on pregnant women and the fetus have been limited by the fact that only a small number of models exist with rather coarse anatomical details and a poor representation of the anatomical variability of the fetus shape and its position over the entire gestation. In this paper, we propose a new computational framework to generate 3D hybrid models of pregnant women, composed of fetus shapes segmented from medical images and a generic maternal body envelope representing a synthetic woman scaled to the dimension of the uterus. The computational framework includes the following tasks: image segmentation, contour regularization, mesh-based surface reconstruction, and model integration. A series of models was created to represent pregnant women at different gestational stages and with the fetus in different positions, all including detailed tissues of the fetus and the utero-fetal unit, which play an important role in dosimetry. These models were anatomically validated by clinical obstetricians and radiologists who verified the accuracy and representativeness of the anatomical details, and the positioning of the fetus inside the maternal body. The computational framework enables the creation of detailed, realistic, and representative fetus models from medical images, directly exploitable for dosimetry simulations. (orig.)

  6. Consistency of external dosimetry in epidemiologic studies of nuclear workers

    International Nuclear Information System (INIS)

    Fix, J.J.; Gilbert, E.S.

    1992-01-01

    Efforts are underway to pool data from epidemiologic studies of nuclear workers to obtain more precise estimates of radiation risk than would be possible from any single study. The International Agency for Research on Cancer (IARC) is coordinating combined analyses of data from studies in the United States, Canada, and the United Kingdom. In the U.S., the Department of Energy (DOE) has established the Comprehensive Epidemiologic Data Resource (CEDR) to provide investigators an opportunity to analyze data from several DOE laboratories. IARC investigators, in collaboration with those conducting the individual studies, have developed a dosimetry protocol for the international combined analyses. (author)

  7. Consistency of external dosimetry in epidemiologic studies of nuclear workers

    International Nuclear Information System (INIS)

    Fix, J.J.; Gilbert, E.S.

    1992-05-01

    Efforts are underway to pool data from epidemiologic studies of nuclear workers to obtain more precise estimates of radiation risk than would be possible from any single study. The International Agency for Research on Cancer (IARC) is coordinating combined analyses of data from studies in the United States, Canada, and the United Kingdom. In the US, the Department of Energy (DOE) has established the Comprehensive Epidemiologic Data Resource (CEDR) to provide investigators an opportunity to analyze data from several DOE laboratories. IARC investigators, in collaboration with those conducting the individual studies, have developed a dosimetry protocol for the international combined analyses

  8. Biological dosimetry: the potential use of radiation-induced apoptosis in human T-lymphocytes

    International Nuclear Information System (INIS)

    Menz, R.; Andres, R.; Larsson, B.; Ozsahin, M.; Crompton, N.E.A.; Trott, K.

    1997-01-01

    An assay for biological dosimetry based on the induction of apoptosis in human T-lymphocytes is described. Radiation-induced apoptosis was assessed by flow cytometric identification of cells displaying apoptosis-associated DNA condensation. CD4 and CD8 T-lymphocytes were analysed. They were recognized on the basis of their cell-surface antigens. Four parameters were measured for both cell types: cell size, granularity, antigen immunofluorescence and DNA content. Apoptosis was quantified as the fraction of CD4-, or CD8-positive cells with a characteristic reduction of cell size and DNA content. At doses below 1 Gy, levels of radiation-induced apoptosis increased for up to 5 days after irradiation. Optimal dose discrimination was observed 4 days after irradiation, at which time the dose-response curves were linear, with a slope of 8% ± 0.5% per 0.1 Gy. In controlled, dose-response experiments the lowest dose level at which the radiation-induced apoptosis frequency was still significantly above control was 0.05 Gy. After 5 days post-irradiation incubation, intra- and interdonor variations were measured and found to be similar; thus, apoptotic levels depend more on the dose than on the donor. The results demonstrate the potential of this assay as a biological dosimeter. (orig.)

  9. Challenges of analysing suspected over exposed subjects using biological dosimetry at Sri Ramachandra University

    International Nuclear Information System (INIS)

    Vijayalakshimi, J.; Venkatachalam, P.; Solomon, F.D. Paul

    2016-01-01

    Biological dosimetry based on the analysis of dicentric chromosomes has become a routine component of the radiological protection programmes and has a valuable role to contribute in suspected over exposed subjects who perform diagnostic and therapeutic procedures. The Department of Human Genetics, Sri Ramachandra University, Porur, Chennai, has been involved in the standardization of chromosomal aberration analysis as a biological dosimeter for investigating accidental ionising radiation exposure since 1998. Our laboratory has been accredited since 2007 by Atomic Energy Regulatory Board. The initial process was to establish the in vitro dose response curve for various type of low LET ionizing radiation. Since accreditation, a total of 61 subjects have been referred to Sri Ramachandra University from SRRC, Kalpakkam. Brief social/medical history and informed consent are being obtained prior to blood samplings. The dose estimates expressed in sievert (Sv) measured by Thermoluminescence badges was in the range of 0.05-2779.05 mSv. Chromosomal aberration assay was used for analysis which allows direct detection of aberration in peripheral blood lymphocytes. The test was performed as per the standard operating protocol on peripheral blood lymphocyte. Currently the dose response curve for the automated scoring process in under way and we hope to improve upon quality and turnaround time using the automation available. Future challenge would be to establish an in vitro dose response curve with automated scoring technique and developing inter-laboratory comparison of dose response generated using automation

  10. Solid State and Chemical Radiation Dosimetry in Medicine and Biology. Proceedings of a Symposium

    International Nuclear Information System (INIS)

    1967-01-01

    Proceedings of a Symposium organized by the IAEA and held in Vienna, 3-7 October 1966. The meeting was attended by 104 participants from 21 countries and three international organizations. Contents: Solid state dosimetry (17 papers); Chemical dosimetry (10 papers); Invited lectures (2 papers); General aspects and other methods of dosimetry (6 papers); Panel discussion on research and development needed in dosimetry. Each paper is in its original language (32 English, 2 French and 1 Spanish) and is preceded by an abstract in English and one in the original language, if this is not English. Discussions are in English. (author)

  11. Solid State and Chemical Radiation Dosimetry in Medicine and Biology. Proceedings of a Symposium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1967-03-15

    Proceedings of a Symposium organized by the IAEA and held in Vienna, 3-7 October 1966. The meeting was attended by 104 participants from 21 countries and three international organizations. Contents: Solid state dosimetry (17 papers); Chemical dosimetry (10 papers); Invited lectures (2 papers); General aspects and other methods of dosimetry (6 papers); Panel discussion on research and development needed in dosimetry. Each paper is in its original language (32 English, 2 French and 1 Spanish) and is preceded by an abstract in English and one in the original language, if this is not English. Discussions are in English. (author)

  12. Spectroscopic studies of irradiated glasses: Application in nuclear dosimetry

    International Nuclear Information System (INIS)

    Farah, Khaled

    2010-01-01

    The present work aims to study the effects of ionizing radiation on silicate glasses in order to develop a new dosimetry system simple, precise, stable and inexpensive. Indeed, changes in mechanical properties, optical and paramagnetic glasses when subjected to ionizing radiation. The prediction of long-term behavior, physical aging under irradiation, the glass is paramount. many studies have brought many ways to avoid obscuring glass windows used in nuclear reactors or hot cells and optical devices. Recently, much work has concentrated on the application of the color induced by irradiation for developing a recyclable glass in the glass industry is of great interest economically and environmentally.

  13. Dosimetry, instrumentation and exposure chambers for dc magnetic field studies

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1979-03-01

    The principal objective of this report is to describe in detail an exposure chamber that was developed at the Lawrence Berkeley Laboratory for automated, noninvasive studies of rodent physiology during exposure to high DC magnetic fields. A second objective is to discuss some of the unique instrumentation problems that must be overcome in order to record bioelectric signals from laboratory animals in the presence of a magnetic field. Finally, a description will be given of the various dosimetry techniques that can be employed for quantitation of magnetic field strength

  14. Dosimetry studies during breast cancer radiation treatment

    International Nuclear Information System (INIS)

    Ahmed, M. O. M.

    2005-06-01

    Previous studies indicated that breast cancer is wildly spread especially in women as compared to men. It is increased after an age of thirty five years in women so it is important to study the effect of exposure to the radiation on the intact breast during the treatment of the breast suffering from cancer. In this work the scattered doses for the intact breast during the treatment of the breast suffering from cancer were measured and also the probability of inducing cancer in it is also discussed. The study was performed for a group of patients composed of twenty five females. Also the backscattered doses to the intact breast were measured for thirteen female patients. During the treatment using gamma rays from Co-60 source the two tangential fields (lateral and medial) were selected for the measurements. The results of exposure to gamma radiation for the lateral and medial fields showed that the mean scattered and backscattered doses to the intact breast were (241.26 cGY,47.49 cGY) and (371.6 cGY,385.4 cGY), respectively. Beside that the somatic risk of induced cancer to the intact breast was found to be (6 .1X10 -3 ,1.2X10 -3 ) and (9.29X10 -3 , 9.63X10 -3 ), respectively. From the results obtained it was concluded that the intact breast received small amounts of radiation doses which may lead to breast cancer for the healthy breast. The recommendations from the present study are to take care of radiation protection to the patient, and also to take care of the patient treatment conditions like temperature, pressure and humidity during the radiation exposure.(Author)

  15. Reconstruction of absorbed dose by methods biological dosimetry inhabitans living in Semipalatinsk Nuclear Test Site

    International Nuclear Information System (INIS)

    Abildinova, G.

    2010-01-01

    As a result perennial overland and atmospheric test the nucleus weapon on Semipalatinsk nucler test site (NTS) about 1,2 ml person were subjected to frequentative sharp and chronic irradiation in different range of doses. Besides a significant number of battle radioactive matters tests with radionuclei dispersion on soil surface and an atmosphere was realized also. All this activity has caused the significant radioactive contamination and damage to an environment, and the local population has received extra exposure to radiation. These circumstances have essentially complicated the economy development of the given region. Aim: Reconstruction of absorbed dose by modern methods biological dosimetry beside inhabitants living in region of influence Semipalatinsk NTS. The cytogenetically examination of population Semipalatinsk region, living in different zones radiation risk: s. Dolon, s. Sarzhal, s. Mostik. Installed that total frequency of chromosome aberrations forms 4,8/100; 2,1/100; 2,5/100 cells, accordingly. High level of chromosome aberrations is conditioned to account radiations markers - acentric fragments (2,1/100 cells in s. Dolon; 1,09/100 cells in s. Sarzhal; 0,79/100 cells in s. Mostik); dysenteric and ring chromosomes (0,6; 0,2; 0,11) and stable type chromosome aberrations (1,02; 0,3; 1,0, accordingly). Frequency and spectrum of chromosome aberrations are indicative of significant mutation action ionizing radiations on chromosome device of somatic cells. Studied dependency an cytogenetically of effects from dose of irradiation within before 0,5 Gr in vitro for calibrated curve standard when undertaking reconstruction efficient dose at the time of irradiations examined group of population. Dependency is described the model a*cos(x) 1 + sin (x), where x - correlation a dysenteric and ring chromosomes to acentric fragments. Dependence of cytogenetic parameters upon ESR-doses had been studied. Had been received dependences: for the total frequency of

  16. The use of apoptosis in human lymphocytes peripheral as alternative methods in biological dosimetry of radiation effects from cobalt-60

    International Nuclear Information System (INIS)

    Lemes, Marisa

    1997-01-01

    Gamma rays affect cells in dose-response manner, resulting in cell death, as in cancer radiotherapy. The ionizing radiation acts by transferring energy, mainly by free radicals from water radiolysis that result in nucleic acid damage and other effects in lipids and proteins, The level of exposure is indirectly estimated by physical dosimetry, but the biological dosimetry can measure the direct radiation effect, mainly in post-dividing cells by classical cytogenetic approach. Recently, it was reported that irradiated cells develop an induced programmed death or apoptosis. With a biological dosimetric technique, we measured apoptotic cell fraction in 60 Co in vitro irradiated blood cells from voluntary healthy donors. The agarose gel electrophoresis showed a low sensitivity, because cell DNA presented the characteristic pattern only when the cells were exposed to 100 c Gy or more. Using a terminal DNA labeling technique we observed that the apoptotic cell fraction proportionally increases with irradiation. Similar sensitivity was observed when compared to classical cytogenetics (3 c Gy minimum detection level). These techniques are easier to perform, do not need cell culture and all cells, including interphase ones, can be analyzed, providing a good tool in biological dosimetry. (author)

  17. Comparative study of Si diodes for gamma radiation dosimetry

    International Nuclear Information System (INIS)

    Pascoalino, Kelly Cristina da Silva

    2010-01-01

    In this work it is presented the comparative study of Si diodes response for gamma radiation dosimetry. The diodes investigated, grown by float zone (Fz) and magnetic Czochralski (MCz) techniques, were processed at the Physics Institute of Helsinki University in the framework of the research and development of rad-hard silicon devices. To study the dosimetric response of these diodes they were connected in the photovoltaic mode to the input of a digital electrometer to measure the photocurrent signal due to the incidence of gamma-rays from a 60 Co source (Gammacell 220). The dosimetric parameter utilized to study the response of these devices was the charge, obtained trough the integration of the current signals, as a function of the absorbed dose. Studies of the influence of the pre-irradiation procedures on both sensitivity and stability of these diodes showed that the sensitivity decreased with the total absorbed dose but after a preirradiation of about 873 kGy they became more stable. Radiation damage effects eventually produced in the devices were monitored trough dynamic current and capacitance measurements after each irradiation step. Both samples also exhibited good response reproducibility, 2,21% (Fz) and 2,94% (MCz), obtained with 13 consecutive measurements of 15 kGy compared with the equivalent 195 kGy absorbed dose in one step of irradiation. It is important to note that these results are better than those obtained with routine polymethylmethacrylate (PMMA) dosimeters used in radiation processing dosimetry. (author)

  18. A study on the retrospective dosimetry using electron paramagnetic resonance spectroscopy of tooth enamel

    International Nuclear Information System (INIS)

    Hong, Dae Seok

    2004-02-01

    Retrospective dosimetry is a process that is a part of dose reconstruction for estimation of exposed dose occurred years before the estimation. Dose reconstruction may be required in a variety of situations such as acute accidental exposure, suspected chronic overexposure and reassessment of occupational exposure. The techniques for retrospective can be classified as biological method and physical method. As a distinct physical technique for dose reconstruction, EPR (Electron Paramagnetic Resonance) or ESR (Electron Spin Resonance) dosimetry has been widely used. In EPR dosimetry, electrons generated by the interaction of material with radiation and trapped in lattice are measured by microwave absorption spectroscopy. Among the materials used for EPR dosimetry, tooth enamel has a high sensitivity for ionising radiation and since the tooth follows the carrier in all situations, it can act as a lifetime-dosimeter. And it is considered as one of the important biological samples. In many countries, there have been a lot of studies and practical applications on EPR dosimetry with tooth enamel. This technique has been applied for A-bomb survivors, Techa riverside population, Chernobyl cleanup workers and so on. Also there were two times of international comparison of the results of EPR dosimetry with tooth enamel in 1996 and 2000 respectively. But the experts have yet to reach a consensus on the best method. So, a lot of methods have been used for the separation of enamel from teeth and this may influence the dose evaluation. With the factors affecting EPR spectrum, this can effect on the results of dose reconstructed. In this study, factors affecting the EPR spectrum of tooth are experimented first. Anisotropy of radiation induced CO 2 - radical is negligible at low doses, but it become important at high doses. It can induce errors in dose estimation up to 40% at dose range of 5Gy. So, crushing process is essential in dose estimation. But, since sample grinding can

  19. Neutron dosimetry - A review

    Energy Technology Data Exchange (ETDEWEB)

    Baum, J W

    1955-03-29

    This review summarizes information on the following subjects: (1) physical processes of importance in neutron dosimetry; (2) biological effects of neutrons; (3) neutron sources; and (4) instruments and methods used in neutron dosimetry. Also, possible improvements in dosimetry instrumentation are outlined and discussed. (author)

  20. Dosimetry study for electron beam irradiation in radiation processing

    International Nuclear Information System (INIS)

    Sunaga, Hiromi; Haruyama, Yasuyuki; Takizawa, Haruki; Kojima, Takuji; Yotsumoto, Keiichi

    1995-01-01

    For certain critical applications such as medical device sterilization and food irradiation, accurate calibration of electron energy and absorbed dose is required to assure the quality of irradiated products. To meet this requirement, TRCRE, JAERI has carried out research and development on high dose radiation dosimetry for electron beams in the energy range used in radiation processing (0.15 - 3.0 MeV). JAERI has developed a simultaneous electron beam energy and dosimeter calibration system that consist of a total absorption calorimeter, an electron current density meter, and a stacked thin-film dosimeter set. For low energy electrons, where it is important to measure the depth-dose profile in materials with high depth resolution, we studied the feasibility of a method using Gafchromic film dosimeters. This film, which has an 8-μm thick sensitive layer, is combined with a stepped array of absorber films of the same thickness to produce a high-resolution depth-dose profile on the Gafchromic film. The depth-dose profile obtained in this manner has about five times greater resolution than conventional radiochromic film dosimetry. (author)

  1. Biological in vivo dosimetry with an external measuring technique under application of a labelled DNA-precursor (iodine-125-desoxyuridine)

    International Nuclear Information System (INIS)

    Porschen, W.; Zamboglou, N.; Muehlensiepen, H.; Feinendegen, L.E.

    1976-01-01

    The depression of the incorporation rate of IDU in the whole body or in the bone marrow is a sensitive indicator for a whole-body irradiation. It was found that the maximum effect is observed some 4 hours after irradiation. For this reason, bone marrow cells were labelled in vitro with IDU 4 hours after whole-body irradiation. This method proved to be extraordinarily sensitive and resulted in reproducible effects which occurred already at doses below 5 rad. All the other biological methods of dosimetry known so far are less sensitive. Although the theory explaining these results is not yet fully clarified, this method of dosimetry appears to offer practical possibilities of application. (orig.) [de

  2. Study of biological compartments

    International Nuclear Information System (INIS)

    Rocha, A.F.G. da

    1976-01-01

    The several types of biological compartments are studied such as monocompartmental system, one-compartment balanced system irreversible fluxes, two closed compartment system, three compartment systems, catenary systems and mammilary systems [pt

  3. The Relevance of Chromosome Aberration Yields for Biological Dosimetry After Low-Level Occupational Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bauchinger, M.; Schmid, E.; Hug, O. [Gesellschaft fuer Strahlenforschung, Institut fuer Biologie, Neuherberg, Federal Republic of Germany (Germany); Strahlenbiologisches Institut der Universitaet Muenchen, Federal Republic of Germany (Germany)

    1971-06-15

    The usefulness of chromosome analysis for biological dosimetry has been tested in two groups of persons occupationally exposed to radiation: (I) in nurses employed in gynaecological radiology, exposed especially when handling radium inserts; and (II) in nuclear industry workers, all of which were exposed to external gamma irradiation and some of them also to internal radiation after incorporation of various radionuclides. The total dose registered with personal dosimeters ranged in Group 1 from 0.1 to 91.1 rem accumulated over working periods of 0.1 to 13 years, and in Group II from 1.0 to 18.2 rem accumulated over 1 to 9 years. Compared with unexposed controls, both groups exhibit a significant increase of cells with chromosome aberrations as well as larger numbers of breaks per cell. Dicentrics and rings could be observed in some cells, providing good evidence for previous radiation exposure, since these types of aberrations are extremely rare events in unexposed individuals. No correlation between the aberration yields and the film badge values could be demonstrated in Group II. Also, in Group I the fluctuations from individual to individual are rather high. Nevertheless, a positive correlation to the ''dose'' was obtained. Even a sub-group of the nurses that had only been exposed to 20 rem showed significantly more aberrations than control persons. From the results obtained, type and frequency of chromosome aberrations may be considered an indicator of radiation exposure even at the low doses. The reasons for lack of correspondence of chromosome aberration yields and the results of personal monitoring procedures are discussed in detail. (author)

  4. Dosimetry implications of BSH biodistribution study at OSU

    International Nuclear Information System (INIS)

    Gupta, N.; Albertson, B.J.; Gahbauer, R.A.; Barth, R.F.; Goodman, J.H.

    2000-01-01

    A BSH biodistribution study was performed at Ohio State University, where tumor, normal brain, and blood boron concentrations of patients undergoing tumor debulking surgery were acquired. The results of this biodistribution study are subjects of other presentations in this meeting. In this paper, we present an overview of the dosimetry implications of this biodistribution data. The analysis for this paper assumed that the tumor boron RBE was factor of two higher than the normal brain boron RBE. Our conclusions from this analysis were that with the tumor/blood ratios observed in our patients for times of up to 14 hours post commencement of boron infusion, one could not successfully treat patients with BNCT using BSH. (author)

  5. Techniques for radiation measurements: Micro-dosimetry and dosimetry

    International Nuclear Information System (INIS)

    Waker, A. J.

    2006-01-01

    Experimental Micro-dosimetry is concerned with the determination of radiation quality and how this can be specified in terms of the distribution of energy deposition arising from the interaction of a radiation field with a particular target site. This paper discusses various techniques that have been developed to measure radiation energy deposition over the three orders of magnitude of site-size; nano-meter, micrometer and millimetre, which radiation biology suggests is required to fully account for radiation quality. Inevitably, much of the discussion will concern the use of tissue-equivalent proportional counters and variants of this device, but other technologies that have been studied, or are under development, for their potential in experimental Micro-dosimetry are also covered. Through an examination of some of the quantities used in radiation metrology and dosimetry the natural link with Micro-dosimetric techniques will be shown and the particular benefits of using Micro-dosimetric methods for dosimetry illustrated. (authors)

  6. Studies of photodynamic therapy: Investigation of physiological mechanisms and dosimetry

    Science.gov (United States)

    Woodhams, Josephine Helen

    Photodynamic therapy (PDT) is a treatment for a range of malignant and benign lesions using light activated photosensitising drugs in the presence of molecular oxygen. PDT causes tissue damage by a combination of processes involving the production of reactive oxygen species (in particular singlet oxygen). Since the PDT cytotoxic effect depends on oxygen, monitoring of tissue oxygenation during PDT is important for understanding the basic physiological mechanisms and dosimetry of PDT. This thesis describes the use of non-invasive, optical techniques based on visible light reflectance spectroscopy for the measurement of oxy- to deoxyhaemoglobin ratio or haemoglobin oxygen saturation (HbSat). HbSat was monitored at tissue sites receiving different light dose during aluminium disulphonated phthalocyanine (AIS2PC) PDT. Results are presented on real time PDT-induced changes in HbSat in normal tissue (rat liver) and experimental tumours, and its correlation with the final biological effect under different light regimes, including fractionated light delivery. It was found to some extent that changes in HbSat could indicate whether the tissue would be necrotic after PDT and it was concluded that online physiological dosimetry is feasible for PDT. The evaluation of a new photosensitiser for PDT called palladium-bacteriopheophorbide (WST09) has been carried out in normal and tumour tissue in vivo. WST09 was found to exert a strong PDT effect but was active only shortly after administration. WST09 produced substantial necrosis in colonic tumours whilst only causing a small amount of damage to the normal colon under certain conditions indicating a degree of selectivity. Combination therapy with PDT for enhancing the extent of PDT-induced damage has been investigated in vivo by using the photochemical internalisation (PCI) technique and Type 1 mechanism enhanced phototoxicity with indole acetic acid (IAA). PCI of gelonin using AIS2PC PDT in vivo after systemic administration of

  7. The biological response of plucked human hair to low-dose radiation: a measure of individual radiosensitivity and a technique for biological dosimetry

    International Nuclear Information System (INIS)

    Swain, D.

    1997-01-01

    It is often assumed that the effects of radiation are linear with dose and that high dose effects can be extrapolated to low dose levels. However, there are a variety of mechanisms which can alter the response at low doses. The most important of these relate to induced sensitivity or induced repair mechanisms. It is therefore important that this area is studied in more depth by looking at the molecular effects and damage to cells at low doses. It is well known that there are certain rare genetic syndromes which predispose individuals to cancer, e.g. ataxia telangiectasia. It is also probable that there is a large range of sensitivity in the natural variation of individuals to the risk of radiation-induced cancer. It is proposed that radiosensitivity is studied using stimulated lymphocytes from whole blood and the technique extended to look at the effects in cell cultures established from human hair. Radiation treatment of cell cultures established from plucked human hair has been previously advocated as a non-invasive technique for non-uniform biological dosimetry and it is proposed that these techniques are adapted to the use of hair to estimate individual radiosensitivity. The aim is to establish and optimize these techniques for culturing keratinocytes from plucked human hair follicles with a view to study biological markers for the subsequent assessment of radiosensitivity. Preliminary results are promising and suggest that the technique for culturing keratinocytes from hair presents a feasible approach. Results from this primary cell culture technique and results from the comparison of the micronuclei data obtained from the cell cultures and stimulated lymphocytes will be presented. (author)

  8. Biological dosimetry of ionizing radiation: Evaluation of the dose with cytogenetic methodologies by the construction of calibration curves

    Science.gov (United States)

    Zafiropoulos, Demetre; Facco, E.; Sarchiapone, Lucia

    2016-09-01

    In case of a radiation accident, it is well known that in the absence of physical dosimetry biological dosimetry based on cytogenetic methods is a unique tool to estimate individual absorbed dose. Moreover, even when physical dosimetry indicates an overexposure, scoring chromosome aberrations (dicentrics and rings) in human peripheral blood lymphocytes (PBLs) at metaphase is presently the most widely used method to confirm dose assessment. The analysis of dicentrics and rings in PBLs after Giemsa staining of metaphase cells is considered the most valid assay for radiation injury. This work shows that applying the fluorescence in situ hybridization (FISH) technique, using telomeric/centromeric peptide nucleic acid (PNA) probes in metaphase chromosomes for radiation dosimetry, could become a fast scoring, reliable and precise method for biological dosimetry after accidental radiation exposures. In both in vitro methods described above, lymphocyte stimulation is needed, and this limits the application in radiation emergency medicine where speed is considered to be a high priority. Using premature chromosome condensation (PCC), irradiated human PBLs (non-stimulated) were fused with mitotic CHO cells, and the yield of excess PCC fragments in Giemsa stained cells was scored. To score dicentrics and rings under PCC conditions, the necessary centromere and telomere detection of the chromosomes was obtained using FISH and specific PNA probes. Of course, a prerequisite for dose assessment in all cases is a dose-effect calibration curve. This work illustrates the various methods used; dose response calibration curves, with 95% confidence limits used to estimate dose uncertainties, have been constructed for conventional metaphase analysis and FISH. We also compare the dose-response curve constructed after scoring of dicentrics and rings using PCC combined with FISH and PNA probes. Also reported are dose response curves showing scored dicentrics and rings per cell, combining

  9. Contribution of new cytogenetic techniques in the estimations of old irradiations in retrospective biological dosimetry

    International Nuclear Information System (INIS)

    Pouzoulet, F.

    2007-10-01

    The objective of this study was to answer three questions: if the translocations are steady: the results have shown that the translocations even if they are not obligatory steady can be used in retrospective dosimetry. Furthermore, it appeared important to consider the complex translocations in view of their relative stability and complementary information they bring ( quality of radiation, received dose). The second question is what contribution of the M-F.I.S.H. in the translocations analysis in comparison with the F.I.S.H.-3: we have shown that the M-F.I.S.H. would allow to raise the whole of doubt due to a partial genome observation. that has for effect to increase the precision of the analysis and that what ever be the received dose. The third question is if there are differences between the chromosomal aberrations generated by x radiation of 50 keV and by gamma radiation from cobalt-60: yes, the low energy photons generate more translocations than the photons coming from cobalt-60. But they generate less dicentrics. this difference comes from the way the energy is deposited that leads to a more important formation of complex and multiple translocations with the low energy photons. this could constitute a problem in the use of low energy photons in radiotherapy. it would seem that the simple translocations rate is not influenced by the photons energy. (N.C.)

  10. Aquatic biology studies

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Aquatic biology studies focused on studying the hydrothermal effects of Par Pond reservoir on periphyton, plankton, zooplankton, macrophytes, human pathogens, and microbial activity; the variability between the artificial streams of the Flowing Streams Laboratory and Upper Three Runs Creek; and the bacterial production of methane in Savannah River Plant aquatic systems

  11. A contribution to the study and development of radiothermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Portal, Guy.

    1975-10-01

    The applications of radiothermoluminescence to radiation dosimetry were investigated. The fundamental processes are first reviewed and the main properties of radiothermoluminescence dosemeters are stated. The investigations carried out in order to have materials presenting particular dosimetric characteristics are then described: a lithium fluoride stabilized by sodium that can be reused without regeneration an alumina suitable for dosimetry in case of accident. Finally, the measurement of electromagnetic radiation in presence of neutrons of various energies are considered [fr

  12. Biological dosimetry of ionizing radiation by chromosomal aberration analysis; Dosimetria biologica de las radiaciones ionizantes mediante el analisis de aberraciones cromosomicas

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Castano, S.; Silva, A.; Navlet, J.

    1990-07-01

    Biological dosimetry consists of estimating absorbed doses for people exposed to radiation by mean biological methods. Several indicators used are based in haematological, biochemical, and cytogenetic data, although nowadays without doubt, the cytogenetic method is considered to be the most reliable. In this case, the study ol chromosomal aberrations, normally dicentric chromosomes, in peripheral lymphocytes can be related to absorbed dose through an experimental calibration curve. An experimental dose-response curve, using dicentric chromosomes analysis, X-rays at 300 kVp, 114 rad/min and temperature 37 degree celsius has been produced. Experimental data is fitted to model Y ={alpha} + {beta}{sub 1}D + {beta}{sub 2}D 2 , where Y is the number of dicentrics per cell and D the dose. The curve is compared with those produced elsewhere. (Author) 14 refs.

  13. Dose intercomparison studies for standardization of high-dose dosimetry in Viet Nam

    International Nuclear Information System (INIS)

    Mai Hoang Hoa; Duong Nguyen Dinh; Kojima, T.

    1999-01-01

    The Irradiation Center of the Vietnam Atomic Energy Commission (IC-VAEC) is planning to establish a traceability system for high-dose dosimetry and to provide high-dose standards as a secondary standard dosimetry laboratory (SSDL) level in Vietnam. For countries which do not have a standard dosimetry laboratory, the participation in the International Dose Assurance Service (IDAS) operated by the International Atomic Energy Agency (IAEA) is the most common means to verify own dosimetry performance with a certain uncertainty. This is, however, only one-direction dose intercomparison with evaluation by IAEA including unknown parameter at participant laboratories. The SSDL level laboratory should have traceability as well as compatibility, ability to evaluate uncertainties of its own dosimetry performance by itself In the present paper, we reviewed our dosimetry performance through two-way dose intercomparison studies and self-evaluation of uncertainty in our dosimetry procedure. The performance of silver dichromate dosimeter as reference transfer dosimeter in IC-VAEC was studied through two-way blind dose intercomparison experiments between the IC-VAEC and JAERI. As another channel of dose intercomparison with IAEA, alanine dosimeters issued by IDAS were simultaneously irradiated with the IC-VAEC dichromate dosimeters at IC-VAEC and analyzed by IAEA. Dose intercomparison between IC-VAEC and JAERI results into a good agreement (better than ±2.5%), and IDAS results also show similar agreement within ±3.0%. The uncertainty was self-estimated on the basis of the JAERI alanine dosimetry, and a preliminary value of about 1.86% at a 68% confidence level is established. The results from these intercomparisons and our estimation of the uncertainty are consistent. We hope that our experience is valuable to other countries which do not have dosimetry standard laboratories and/or are planning to establish them. (author)

  14. Dosimetry in radiobiological studies with the heavy ion beam of the Warsaw cyclotron

    International Nuclear Information System (INIS)

    Kaźmierczak, U.; Banaś, D.; Braziewicz, J.; Czub, J.; Jaskóła, M.; Korman, A.; Kruszewski, M.; Lankoff, A.; Lisowska, H.; Malinowska, A.; Stępkowski, T.; Szefliński, Z.

    2015-01-01

    The aim of this study was to verify various dosimetry methods in the irradiation of biological materials with a 12 C ion beam at the Heavy Ion Laboratory of the University of Warsaw. To this end the number of ions hitting the cell nucleus, calculated on the basis of the Si-detector system used in the set-up, was compared with the number of ion tracks counted in irradiated Solid State Nuclear Track Detectors and with the number of ion tracks detected in irradiated Chinese Hamster Ovary cells processed for the γ-H2AX assay. Tests results were self-consistent and confirmed that the system serves its dosimetric purpose.

  15. Dosimetry in radiobiological studies with the heavy ion beam of the Warsaw cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Kaźmierczak, U. [Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A, 02-093 Warsaw (Poland); Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093 Warsaw (Poland); Banaś, D.; Braziewicz, J. [Institute of Physics, Jan Kochanowski University, ul. Świętokrzyska 15, 25-406 Kielce (Poland); Holycross Cancer Center, ul. Artwińskiego 3, 25-734 Kielce (Poland); Czub, J. [Institute of Physics, Jan Kochanowski University, ul. Świętokrzyska 15, 25-406 Kielce (Poland); Jaskóła, M.; Korman, A. [National Centre for Nuclear Research, ul. Andrzeja Sołtana 7, 05-400 Otwock (Poland); Kruszewski, M. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Institute of Rural Health, ul. Jaczewskiego 2, 20-090 Lublin (Poland); Lankoff, A. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Institute of Biology, Jan Kochanowski University, ul. Świętokrzyska 15, 25-406 Kielce (Poland); Lisowska, H. [Institute of Biology, Jan Kochanowski University, ul. Świętokrzyska 15, 25-406 Kielce (Poland); Malinowska, A. [National Centre for Nuclear Research, ul. Andrzeja Sołtana 7, 05-400 Otwock (Poland); Stępkowski, T. [Institute of Nuclear Chemistry and Technology, ul. Dorodna 16, 03-195 Warsaw (Poland); Szefliński, Z. [Heavy Ion Laboratory, University of Warsaw, ul. Pasteura 5A, 02-093 Warsaw (Poland); and others

    2015-12-15

    The aim of this study was to verify various dosimetry methods in the irradiation of biological materials with a {sup 12}C ion beam at the Heavy Ion Laboratory of the University of Warsaw. To this end the number of ions hitting the cell nucleus, calculated on the basis of the Si-detector system used in the set-up, was compared with the number of ion tracks counted in irradiated Solid State Nuclear Track Detectors and with the number of ion tracks detected in irradiated Chinese Hamster Ovary cells processed for the γ-H2AX assay. Tests results were self-consistent and confirmed that the system serves its dosimetric purpose.

  16. Dosimetric characterization of two radium sources for retrospective dosimetry studies

    Energy Technology Data Exchange (ETDEWEB)

    Candela-Juan, C., E-mail: ccanjuan@gmail.com [Radiation Oncology Department, La Fe University and Polytechnic Hospital, Valencia 46026, Spain and Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Karlsson, M. [Division of Radiological Sciences, Department of Medical and Health Sciences, Linköping University, Linköping SE 581 85 (Sweden); Lundell, M. [Department of Medical Physics and Oncology, Karolinska University Hospital and Karolinska Institute, Stockholm SE 171 76 (Sweden); Ballester, F. [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Tedgren, Å. Carlsson [Division of Radiological Sciences, Department of Medical and Health Sciences, Linköping University, Linköping SE 581 85, Sweden and Swedish Radiation Safety Authority, Stockholm SE 171 16 (Sweden)

    2015-05-15

    Purpose: During the first part of the 20th century, {sup 226}Ra was the most used radionuclide for brachytherapy. Retrospective accurate dosimetry, coupled with patient follow up, is important for advancing knowledge on long-term radiation effects. The purpose of this work was to dosimetrically characterize two {sup 226}Ra sources, commonly used in Sweden during the first half of the 20th century, for retrospective dose–effect studies. Methods: An 8 mg {sup 226}Ra tube and a 10 mg {sup 226}Ra needle, used at Radiumhemmet (Karolinska University Hospital, Stockholm, Sweden), from 1925 to the 1960s, were modeled in two independent Monte Carlo (MC) radiation transport codes: GEANT4 and MCNP5. Absorbed dose and collision kerma around the two sources were obtained, from which the TG-43 parameters were derived for the secular equilibrium state. Furthermore, results from this dosimetric formalism were compared with results from a MC simulation with a superficial mould constituted by five needles inside a glass casing, placed over a water phantom, trying to mimic a typical clinical setup. Calculated absorbed doses using the TG-43 formalism were also compared with previously reported measurements and calculations based on the Sievert integral. Finally, the dose rate at large distances from a {sup 226}Ra point-like-source placed in the center of 1 m radius water sphere was calculated with GEANT4. Results: TG-43 parameters [including g{sub L}(r), F(r, θ), Λ, and s{sub K}] have been uploaded in spreadsheets as additional material, and the fitting parameters of a mathematical curve that provides the dose rate between 10 and 60 cm from the source have been provided. Results from TG-43 formalism are consistent within the treatment volume with those of a MC simulation of a typical clinical scenario. Comparisons with reported measurements made with thermoluminescent dosimeters show differences up to 13% along the transverse axis of the radium needle. It has been estimated that

  17. Studies of the properties of some saccharides for lyoluminescence dosimetry

    International Nuclear Information System (INIS)

    Hazin, C.A.

    1983-03-01

    Alternative dosimetric methods for high doses are under investigation in a number of research centres. Dosemeters based on the phenomenon of lyoluminescence, i.e., emission of light following dissolution of irradiated organic and inorganic compounds were proposed in the 70's. In the present work, the response of several saccharides submitted to the radiation from a 60 Co source was studied. In order to carry out the study, a measuring system consisting of a light detection chamber and an electrometric unit was designed and built. Thereafter, studies concerning the change in light yield as a function of dose were carried out. Other investigated factors were the change in light yield with solvent pH and temperature and the stability of the response for long term storage. The results showed that maltose, lactose and glucose behaved properly as dosimetric materials for high dose measurements. Besides, no significant changes in the lyoluminescent response ocurred when the solvent pH and temperature varied around the usual values. These results show that the control of these parameters is not critica for the utilization of the saccharides under study for dosimetry. (Author) [pt

  18. Dosimetry; La dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    Le Couteulx, I.; Apretna, D.; Beaugerie, M.F. [Electricite de France (EDF), 75 - Paris (France)] [and others

    2003-07-01

    Eight articles treat the dosimetry. Two articles evaluate the radiation doses in specific cases, dosimetry of patients in radiodiagnosis, three articles are devoted to detectors (neutrons and x and gamma radiations) and a computer code to build up the dosimetry of an accident due to an external exposure. (N.C.)

  19. In vivo thermoluminescent dosimetry in studies of helicoid computed tomography and excretory urogram

    International Nuclear Information System (INIS)

    Cruz C, D.; Azorin N, J.; Saucedo A, V.M.; Barajas O, J.L.

    2005-01-01

    The dosimetry is the field of measurement of the ionizing radiations. It final objective is to determine the 'absorbed dose' for people. The dosimetry is vital in the radiotherapy, the radiological protection and the treatment technologies by irradiation. Presently work, we develop 'In vivo' dosimetry, in exposed patients to studies of helical computed tomography and excretory urogram. The dosimetry 'in vivo' was carried out in 20 patients selected aleatorily, for each medical study. The absorbed dose was measured in points of interest located in crystalline, thyroid, chest and abdomen of each patient, by means of thermoluminescent dosemeters (TLD) LiF: Mg,Cu,P + Ptfe of national fabrication. Also it was quantified the dose in the working area. (Author)

  20. Biological (DB) and internal dosimetry (DI) in patients with differentiated thyroid carcinoma (CaDT) treated with iodine 131

    International Nuclear Information System (INIS)

    Fadel, Ana M.; Chebel, G.; Oneto, A.; Di Giorgio, Marina; Vallerga, Maria B.; Taja, Maria R.; Radl, A.; Rojo, Ana M.; Deluca, G.; Levi de Cabrejas, Mariana; Cabrejas, Raul C.

    2009-01-01

    The internal 131 I radiotherapy in patients with CaDT is used within the therapeutic scheme as a step post-thyroidectomy. The success of therapy is to achieve a lethal dose in the tumor tissue without exceeding the dose of tolerance in healthy tissues (doses greater than 2 Gy in bone marrow could lead to myelotoxicity). In this work, the treatment protocol applied incorporates assessment by biological (DB) and internal dosimetry (DI) for estimating doses to the whole body and bone marrow to administer a therapeutic personalized for each patient. The estimate biological dose is based in the quantification of chromosomal aberrations, which is referred to a dose-response curve. Objectives: 1) To estimate the absorbed dose to the whole body and bone marrow due to the administration of 131 I therapy in patients with CaDT, by applying three different cytogenetic tests: conventional cytogenetics, micronuclei (MN) and fluorescence in situ hybridization (FISH); 2) Assess the correlation of the results obtained by DB and DI for personalization of treatment. Materials and methods: We evaluated 24 patients with CaDiT by applying the cytogenetic tests mentioned and internal dosimetry (methodology Mird-Olinda). Internal dosimetry: We administered a tracer dose 74 to 111 MBq. Measurements were made of activity in whole body and blood. By adjusting the scheme was estimated MIRD dose in bone marrow and the maximum therapeutic activity to manage and secure. Through software Olinda was determined absorbed dose to the whole body for each patient. We considered patient-specific data (physical frame size, weight, hematocrit) to adjust the methodology in each particular case. It is assumed that the tracer activity administered has a kinetic in the body similar to the 131 I to be administered in therapeutic amounts. Biology Dosimetry : We performed for each patient taking 2 sequential venous blood samples to estimate the dose due to therapeutic activity in review: the first shows, pre

  1. Cytogenetic techniques for biological indications and dosimetry of of radiation damages in humans

    International Nuclear Information System (INIS)

    Hadjidekova, V.

    2003-01-01

    The cytogenetic methods present a proved way for bio-monitoring and bio-dosimetry for persons, submitted to ionising radiation in occupational and emergency conditions. Their application complement and assist the evaluation of the physical dosimetry and takes in account the individual radiosensitivity of the organism. A comparative assessment is made of the cytogenetic markers for radiation damage of humans applied in Bulgaria. It is discussed the sensitivity of the methods and their development in the last years, as well as the basic concept for their application - the causal relationship between the frequency of the observation of cytogenetic markers in peripheral blood lymphocytes and the risk of oncological disease. The conventional analysis of dicentrics is recognised as a 'golden standard' for the quantitative assessment of the radiation damage. The long term persisting translocations reflect properly the cumulative dose burden from chronic exposure. The micronucleus test allows a quick screening of large groups of persons, working in ionising radiation environment. The combined application with centromeric DNA probe improves the sensitivity and presents a modern alternative of the bio-monitoring and bio-dosimetry. It is discussed the advantages of the different cytogenetic techniques and their optimised application for the assessment of the radiation impact on humans

  2. Application of Apollo cosmic radiation dosimetry to lunar colonization studies

    International Nuclear Information System (INIS)

    English, R.A.; Bailey, J.V.; Brown, R.D.

    1972-01-01

    The radiation data gathered from the lunar landing missions of Apollo 11 through Apollo 15 are presented. These data have been analyzed to provide dosimetry evaluation of the ambient radiation and radiation from potential solar particle events for the planning of safe, long-term stays of relatively large numbers of individuals upon the moon. (U.S.)

  3. Retrospective dosimetry using unheated quartz: A feasibility study

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Bøtter-Jensen, L.; Murray, A.S.

    2002-01-01

    Most attempts to apply retrospective dosimetry to building materials have made use of heated (sensitised) items such as brick or tile ceramic. Unfired materials, such as concrete, are far more widespread in the industrial environment, but unfortunately these cannot be assumed to contain a negligi...

  4. Biological effects of radiation and dosimetry in X-ray diagnostics of children

    International Nuclear Information System (INIS)

    Milkovic, Durdica; Beck, Natko; Kovac, Kornelija; Garaj-Vrhovac, Vera; Gajski, Goran

    2008-01-01

    The chest radiograms represent the basic radiological examinations of thorax. The basis for radiation protection especially in pediatrics is the exact determination of doses. The risk estimation of genome damages can be received in human peripheral blood lymphocytes using alkaline version of Comet Assay. The aim of this work was assessment and quantification of the level of DNA damage in peripheral blood lymphocytes of children during airways X-ray examinations of chest and to compare data to the dose of exposure. Doses were determined using thermoluminescence (TL) dosimetry and radiophotoluminescent (RPL) glass dosimetry system. Twenty children with pulmonary diseases, ages between 5 and 14 years were assessed. Dose measurements were conducted for poster-anterior (PA) projection on the forehead, thyroid gland, gonads, chest and back. We used a 150 kV Shimadzu CH-200 M X-ray unit. Peripheral blood samples were taken from children after and prior to X-ray exposure and were examined with the alkaline Comet Assay. Comet Assay is one of the standard techniques for assessing genome damage with variety applications in genotoxicity testing as well as fundamental research in DNA damage and repair. As a measure of DNA damage tail length was used, calculated from the centre of the head and presented in micrometers (μm). Mean value of group after irradiation was 14.04 ± 1.74 as opposed to mean value of group before irradiation that was 13.15 ± 1.33. Differences between mean tail lengths were statistically significant (P<0.05, ANOVA). In addition, correlation was found between doses in primary beam (measured on the back) and the ratio of tail length (DNA damage) before and after irradiation. Doses measured with TL and RPL dosimeters showed satisfactory agreement and both dosimetry methods are suitable for dosimetric measurements in X-ray diagnostics. (author)

  5. Use of unstable chromosome aberrations for biological dosimetry after the first postirradiation mitosis

    International Nuclear Information System (INIS)

    Doloy, M.T.; Malarbet, J.L.; Guedeney, G.; Bourguignon, M.; Leroy, A.; Reillaudou, M.; Masse, R.

    1991-01-01

    The loss of unstable chromosome aberrations after the first postirradiation mitosis makes their use difficult in radiation dosimetry. We describe here a method which, in a cell population observed at this stage, allows retrospective estimation of the frequencies of the unstable aberrations induced at the time of irradiation, and their use as a dosimeter. The laws controlling the behavior of unstable aberrations during mitosis were defined from a large-scale experiment on irradiated human lymphocytes. For cells undergoing the first, second, or third mitosis after irradiation, relationships were determined between the frequency, at irradiation time, of acentric fragments not arising from formation of dicentrics or rings, and the ratio of dicentrics and centric rings appearing without acentric fragments to the total number of dicentrics plus rings. On the basis of this ratio, the method described here provides an assessment of the postirradiation mitotic activity in a cell population. This assessment permitted estimation of the cell distribution and frequency of dicentrics plus centric rings, and of the frequency of acentric fragments at the time of irradiation. The use of this method for retrospective dosimetry after whole-body irradiation under various conditions of exposure is illustrated

  6. Biological and clinical dosimetry. Progress report July 1, 1964-June 30, 1979

    International Nuclear Information System (INIS)

    Laughlin, J.S.; McDonald, J.C.

    1979-01-01

    The dosimetric studies at this laboratory were initiated with the primary goal of developing systems for the determination of absorbed dose in biological research and clinical applications. The primary method under study is the local absorbed dose calorimeter, a concept initiated and developed by J. S. Laughlin. In addition, secondary dosimetric systems such as ionization chambers, chemical dosimeters and thermoluminescent dosimeters (TLD) are being developed and applied to provide an absolute basis for the evaluation and comparison of experiments, treatments, and other procedures using radiation

  7. Study of thermoluminescence and semiconductors in dosimetry. Application of dosimetry of the whole body in view of bone marrow grafting

    International Nuclear Information System (INIS)

    Naudy, Suzanne.

    1981-05-01

    From this study one deduces that thermoluminescence remains the moss reliable process for the measurement of dose in vivo: precision, reproducibility and easy calibration. The semiconductors do not present the quality needed to a reliable use in dosimetry. The limits of each techniques have been established in our study, we have applied them simultaneously in dosimetric irradiations of the whole body in view of bone marrow grafting. Semiconductors allow to follow the irradiation and to intervene instantaneously if necessary, thermoluminescent dosimeter insure precise knowledge of the delivered dose. One hundred and ten patients have been treated before bone narrow grafting at the Gustave Roussy Institut and fifty two of them render account of the results obtained with this experimental dosimetric protocol [fr

  8. Internal sources dosimetry

    International Nuclear Information System (INIS)

    Savio, Eduardo

    1994-01-01

    The absorbed dose, need of estimation in risk evaluation in the application of radiopharmaceuticals in Nuclear Medicine practice,internal dosimetry,internal and external sources. Calculation methodology,Marinelli model,MIRD system for absorbed dose calculation based on biological parameters of radiopharmaceutical in human body or individual,energy of emitted radiations by administered radionuclide, fraction of emitted energy that is absorbed by target body.Limitation of the MIRD calculation model. A explanation of Marinelli method of dosimetry calculation,β dosimetry. Y dosimetry, effective dose, calculation in organs and tissues, examples. Bibliography .

  9. Study and characterization of dosimeter LiF:Mg,Cu,P for using in aeronautical dosimetry

    International Nuclear Information System (INIS)

    Flavia, Hanna; Federico, Claudio; Lelis, Odair; Pereira, Heloisa; Pereira, Marlon

    2014-01-01

    The effects of cosmic ionizing radiation incidents in aircraft components and crews has been a source of concern and motivated increasingly studies and improvements in the area. The low dose rates involved in this radiation field in aircraft flight altitudes imply Dosimetric necessity of using materials with high efficiency of detection, to enable studies lower cumulative doses resulting in shorter routes or lower altitude. The choice of thermoluminescent dosimeters LiF: Mg, Cu, P was done by having a detection efficiency of about fifteen times higher than its predecessor (LiF: Mg, Ti), and therefore, applied in very low doses dosimetry, and environmental dosimetry . The implementation of the use of pair dosimetric TLD-600H and 700H-TLD will serve as support for testing and studies on the effects of low doses of cosmic radiation in environmental dosimetry applied in the aviation environment in the usual flight altitudes. In this paper are presented the results of development of a methodology for dosimetry low doses of gamma radiation and neutrons using the pair dosimetric TLD-600H and 700H-TLD. The results demonstrate a sensitivity of dosimeters well above the dosimeters LiF: Mg, Ti confirming its suitability for dosimetry of low doses

  10. Applications, dosimetry and biological interactions of static and time-varying magnetic fields

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1988-08-01

    The primary topics of this presentation include: (1) the applications of magnetic fields in research, industry, and medical technologies; (2) mechanisms of interaction of static and time-varying magnetic fields with living systems; (3) human health effects of exposure to static and time-varying magnetic fields in occupational, medical, and residential settings; and (4) recent advances in the dosimetry of extremely-low-frequency electromagnetic fields. The discussion of these topics is centered about two issues of considerable contemporary interest: (1) potential health effects of the fields used in magnetic resonance imaging and in vivo spectroscopy, and (2) the controversial issue of whether exposure to extremely-low-frequency (ELF) electromagnetic fields in the home and workplace leads to an elevated risk of cancer. 11 refs

  11. Fundamentals of Dosimetry. Chapter 3

    Energy Technology Data Exchange (ETDEWEB)

    Yoshimura, E. M. [Universidade de São Paulo, São Paulo (Brazil)

    2014-09-15

    Determination of the energy imparted to matter by radiation is the subject of dosimetry. The energy deposited as radiation interacts with atoms of the material, as seen in the previous chapter. The imparted energy is responsible for the effects that radiation causes in matter, for instance, a rise in temperature, or chemical or physical changes in the material properties. Several of the changes produced in matter by radiation are proportional to the absorbed dose, giving rise to the possibility of using the material as the sensitive part of a dosimeter. Also, the biological effects of radiation depend on the absorbed dose. A set of quantities related to the radiation field is also defined within the scope of dosimetry. It will be shown in this chapter that, under special conditions, there are simple relations between dosimetric and field description quantities. Thus, the framework of dosimetry is the set of physical and operational quantities that are studied in this chapter.

  12. Nuclear accident dosimetry intercomparison studies at the Health Physics Research Reactor: a summary (1965-1978)

    International Nuclear Information System (INIS)

    Sims, C.S.; Dickson, H.W.

    1979-01-01

    Fifteen nuclear accident dosimetry intercomparison studies utilizing the fast pulsed Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a growing number of participants with a forum for discussing and learning more about accident dosimetry systems and with opportunity to test their systems under simulated nuclear accident conditions and to compare their results with those of others making measurements under identical conditions. Shielded and unshielded measurements of the neutron and the gamma doses to phantoms and at area monitoring stations have been made with a wide variety of dosimeter types. The large amount of data available from these measurements throughout the years is summarized, analyzed and discussed. The information in this summary provides an indication of the status of and trends in nuclear accident dosimetry. (author)

  13. Fifteenth nuclear accident dosimetry intercomparison study: August 14--22, 1978

    International Nuclear Information System (INIS)

    Sims, C.S.

    1979-05-01

    The fifteenth in the continuing series of Nuclear Accident Dosimetry Intercomparison Studies was held August 14--22, 1978 at the Oak Ridge National Laboratory. The Health Physics Research Reactor, operated in the pulse mode, served as the radiation source. Using different shielding configurations, nuclear accidents with three different neutron and gamma spectra were simulated. Participants from 19 organizations, the most in the history of the studies, exposed dosimeters set up as area monitors as well as dosimeters mounted on phantoms for personnel monitoring. Although many participants performed accurate measurements, the composite dose results, in the majority of cases, failed to meet established nuclear criticality accident dosimetry guidelines which suggest accuracies of +- 25% for neutron dose and +- 20% for gamma dose. This indicates that many participants need to improve their dosimetry systems, their analytical techniques, or both

  14. Analysis of the frequency of mutant T-helpers as a parameter for biological dosimetry

    International Nuclear Information System (INIS)

    Mel'nov, S.B.; Minenko, V.F.; Demidchik, E.P.

    1998-01-01

    It was made the attempt of quantitatively estimation of radiation damage by the frequency of mutant T-helpers, i.e. CD4+cells, depleted of T-cell receptor (TCR). The object of the study was lymphocytes of peripheral blood of children exposed to iodine radioisotopes therapy on medical indications. The examined group consisted of 36 patients 10 -21 years old, which were injected from 0,3 to 27,6 GBq of iodine 131. The time between exposition to iodine 131 and the investigation varied from 2 months to 3 years. The results gave evidence about the existence of direct relation between the frequency of mutant T-helpers and integrated dose. The character of the relation was described on the basis of mathematical processing. It was concluded that TCR-test can be used for restoration of the biological radiation dose

  15. A spectral radioluminescence study for dating and dosimetry

    International Nuclear Information System (INIS)

    Krbetschek, M.R.; Trautmann, T.

    2000-01-01

    The spectral distribution of radioluminescence (RL) and its dose dependence was investigated on various substances to get information about the applicability in dosimetry and dating. The list comprises archaeometallurgical slag components (quartz relicts, glassy fraction), bone, cooking salt, corals, egg shell, flint, mussel shell, natural gypsum, natural halite, quartz (sediments, vein quartz) and sugar. The different emission wave-bands and basic features of their RL-dose-characteristics are reported for 18 different samples. Furthermore results of some materials are discussed in more detail

  16. MIRD Commentary: Proposed Name for a Dosimetry Unit Applicable to Deterministic Biological Effects-The Barendsen (Bd)

    International Nuclear Information System (INIS)

    Sgouros, George; Howell, R. W.; Bolch, Wesley E.; Fisher, Darrell R.

    2009-01-01

    The fundamental physical quantity for relating all biologic effects to radiation exposure is the absorbed dose, the energy imparted per unit mass of tissue. Absorbed dose is expressed in units of joules per kilogram (J/kg) and is given the special name gray (Gy). Exposure to ionizing radiation may cause both deterministic and stochastic biologic effects. To account for the relative effect per unit absorbed dose that has been observed for different types of radiation, the International Commission on Radiological Protection (ICRP) has established radiation weighting factors for stochastic effects. The product of absorbed dose in Gy and the radiation weighting factor is defined as the equivalent dose. Equivalent dose values are designated by a special named unit, the sievert (Sv). Unlike the situation for stochastic effects, no well-defined formalism and associated special named quantities have been widely adopted for deterministic effects. The therapeutic application of radionuclides and, specifically, -particle emitters in nuclear medicine has brought to the forefront the need for a well-defined dosimetry formalism applicable to deterministic effects that is accompanied by corresponding special named quantities. This commentary reviews recent proposals related to this issue and concludes with a recommendation to establish a new named quantity

  17. Dosimetry in dentistry.

    Science.gov (United States)

    Asha, M L; Chatterjee, Ingita; Patil, Preeti; Naveen, S

    2015-01-01

    The purpose of this paper was to review various dosimeters used in dentistry and the cumulative results of various studies done with various dosimeters. Several relevant PubMed indexed articles from 1999 to 2013 were electronically searched by typing "dosimeters", "dosimeters in dentistry", "properties of dosimeters", "thermoluminescent and optically stimulated dosimeters", "recent advancements in dosimetry in dentistry." The searches were limited to articles in English to prepare a concise review on dental dosimetry. Titles and abstracts were screened, and articles that fulfilled the criteria of use of dosimeters in dental applications were selected for a full-text reading. Article was divided into four groups: (1) Biological effects of radiation, (2) properties of dosimeters, (3) types of dosimeters and (4) results of various studies using different dosimeters. The present review on dosimetry based on various studies done with dosimeters revealed that, with the advent of radiographic technique the effective dose delivered is low. Therefore, selection of radiological technique plays an important role in dental dose delivery.

  18. A multi-centre dosimetry audit on advanced radiotherapy in lung as part of the Isotoxic IMRT study

    Directory of Open Access Journals (Sweden)

    Yat Tsang

    2017-10-01

    Conclusion: This multi-centre dosimetry audit of complex IMRT/VMAT delivery provides confidence in the accuracy of modern planning and delivery systems in inhomogeneous tissues. The findings from this study can be used as a reference for future dosimetry audits.

  19. Perofrmance testing of personnel dosimetry services. Final report of a two-year pilot study, October 1977-September 1979

    International Nuclear Information System (INIS)

    Plato, P.; Hudson, G.

    1980-01-01

    A two-year pilot study was conducted of the Health Physics Society Standards Committee (HPSSC) Standard titled, Criteria for Testing Personnel Dosimetry Performance. The objectives of the pilot study were: to give processors an opportunity to correct any problems that are uncovered; to develop operational and administrative prodedures to be used later by a permanent testing laboratory; and to determine whether the proposed HPSSC Standard provides an adequate and practical test of dosimetry performance. Fifty-nine dosimetry processors volunteered to submit dosimeters for test irradiations according to the requirements of the HPSSC Standard. The feasibility of using the HPSSC Standard for a future mandatory testing program for personnel dosimetry processors is discussed. This report shows the results of the pilot study and contains recommendations for revisions in the Standard that will make a mandatory testing program useful to regulatory agencies, dosimetry processors, and radiation workers that use personnel dosimeters

  20. Enhancing Cytogenetic Biological Dosimetry Capabilities of the Philippines for Nuclear Incident Preparedness.

    Science.gov (United States)

    Asaad, Celia O; Caraos, Gloriamaris L; Robles, Gerardo Jose M; Asa, Anie Day D C; Cobar, Maria Lucia C; Asaad, Al-Ahmadgaid

    2016-01-01

    The utility of a biological dosimeter based on the analysis of dicentrics is invaluable in the event of a radiological emergency wherein the estimated absorbed dose of an exposed individual is crucial in the proper medical management of patients. The technique is also used for routine monitoring of occupationally exposed workers to determine radiation exposure. An in vitro irradiation study of human peripheral blood lymphocytes was conducted to establish a dose-response curve for radiation-induced dicentric aberrations. Blood samples were collected from volunteer donors and together with optically stimulated luminescence (OSL) dosimeters and were irradiated at 0, 0.1, 0.25, 0.5, 0.75, 1, 2, 4, and 6 Gy using a cobalt-60 radiotherapy unit. Blood samples were cultured for 48 h, and the metaphase chromosomes were prepared following the procedure of the International Atomic Energy Agency's Emergency Preparedness and Response - Biodosimetry 2011 manual. At least 100 metaphases were scored for dicentric aberrations at each dose point. The data were analyzed using R language program. The results indicated that the distribution of dicentric cells followed a Poisson distribution and the dose-response curve was established using the estimated model, Y dic = 0.0003 (±0.0003) +0.0336 (±0.0115) × D + 0.0236 (±0.0054) × D 2 . In this study, the reliability of the dose-response curve in estimating the absorbed dose was also validated for 2 and 4 Gy using OSL dosimeters. The data were fitted into the constructed curve. The result of the validation study showed that the obtained estimate for the absorbed exposure doses was close to the true exposure doses.

  1. Dosimetry study of [I-131] and [I-125]- meta-iodobenz guanidine in a simulating model for neuroblastoma metastasis.

    Science.gov (United States)

    Roa, W H; Yaremko, B; McEwan, A; Amanie, J; Yee, D; Cho, J; McQuarrie, S; Riauka, T; Sloboda, R; Wiebe, L; Loebenberg, R; Janicki, C

    2013-02-01

    The physical properties of I-131 may be suboptimal for the delivery of therapeutic radiation to bone marrow metastases, which are common in the natural history of neuroblastoma. In vitro and preliminary clinical studies have implied improved efficacy of I-125 relative to I-131 in certain clinical situations, although areas of uncertainty remain regarding intratumoral dosimetry. This prompted our study using human neuroblastoma multicellular spheroids as a model of metastasis. 3D dose calculations were made using voxel-based Medical Internal Radiation Dosimetry (MIRD) and dose-point-kernel (DPK) techniques. Dose distributions for I-131 and I-125 labeled mIBG were calculated for spheroids (metastases) of various sizes from 0.01 cm to 3 cm diameter, and the relative dose delivered to the tumors was compared for the same limiting dose to the bone marrow. Based on the same data, arguments were advanced based upon the principles of tumor control probability (TCP) to emphasize the potential theoretical utility of I-125 over I-131 in specific clinical situations. I-125-mIBG can deliver a higher and more uniform dose to tumors compared to I-131 mIBG without increasing the dose to the bone marrow. Depending on the tumor size and biological half-life, the relative dose to tumors of less than 1 mm diameter can increase several-fold. TCP calculations indicate that tumor control increases with increasing administered activity, and that I-125 is more effective than I-131 for tumor diameters of 0.01 cm or less. This study suggests that I-125-mIBG is dosimetrically superior to I-131-mIBG therapy for small bone marrow metastases from neuroblastoma. It is logical to consider adding I-125-mIBG to I-131-mIBG in multi-modality therapy as these two isotopes could be complementary in terms of their cumulative dosimetry.

  2. Ultraviolet germicidal efficacy as a function of pulsed radiation parameters studied by spore film dosimetry.

    Science.gov (United States)

    Bauer, Stefan; Holtschmidt, Hans; Ott, Günter

    2018-01-01

    Disinfection by pulsed ultraviolet (UV) radiation is a commonly used method, e.g. in industry or medicine and can be carried out either with lasers or broadband UV radiation sources. Detrimental effects to biological materials depending on parameters such as pulse duration τ or pulse repetition frequency f p are well-understood for pulsed coherent UV radiation, however, relatively little is known for its incoherent variant. Therefore, within this work, it is the first time that disinfection rates of pulsed and continuous (cw) incoherent UV radiation studied by means of spore film dosimetry are presented, compared with each other, and in a second step further investigated regarding two pulse parameters. After analyzing the dynamic range of the Bacillus subtilis spore films with variable cw radiant exposures H=5-100Jm -2 a validation of the Bunsen-Roscoe law revealed its restricted applicability and a 28% enhanced detrimental effect of pulsed compared to cw incoherent UV radiation. A radiant exposure H=50Jm -2 and an irradiance E=0.5Wm -2 were found to be suitable parameters for an analysis of the disinfection rate as a function of τ=0.5-10ms and f p =25-500Hz unveiling that shorter pulses and lower frequencies inactivate more spores. Finally, the number of applied pulses as well as the experiment time were considered with regard to spore film disinfection. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Activities of Project 'Cooperation and development with Latin America and Iberian in Biological Dosimetry of Iberian Group of Radiation Protection Societies

    International Nuclear Information System (INIS)

    Nasazzi, Nora B.; Taja, Maria R.; Giorgio, Marina di; Garcia Lima, Omar; Lamadrid, Ana I.; Olivares, Pilar; Moreno, Mercedes; Prieto, Maria J.; Espinosa, Marco

    2001-01-01

    In 1996 the GRIAPRA Group (Latin American and Iberian Group of Radiation Protection Societies) was established with the participation of Argentina, Brazil, Cuba, Mexico, Peru, Portugal and Spain. In 1998 began the biennial Collaborative Working Project 'Cooperation and Development with Latin America in Biological Dosimetry', partially supported by the Extremadura Government, Spain, initially involving five countries: Argentina, Cuba, Peru, Portugal and Spain. The general aim of the project is to create an Latin American and Iberian Biological Dosimetry Laboratories Coordinated Group in order to: give mutual cooperation and to other countries if required, in the case of radiological accident; contribute to enhance the technical capabilities of the participant laboratories; promote the installment of laboratories on this field in countries that does not have it yet through the training of human resources and providing the necessary equipment and, finally, perform jointly research activities in biological dosimetry. The activities designed in order to accomplish the project specific aims for the 1998-2000 period have been achieved. Description and results are presented. (author)

  4. The Utility of Lymphocyte Premature Chromosome Condensation Analysis for Biological Dosimetry Following Accidental Overexposure to Ionising Radiation

    International Nuclear Information System (INIS)

    Chambrette, V.; Laval, F.; Voisin, P.

    1999-01-01

    Premature chromosome condensation (PCC) appears to have a possible utility for biological dosimetry purposes. The PCC technique may be adapted for cases of suspicion of overexposure where sampling is performed at least one day after an accident. For this purpose, human blood samples were exposed in vitro to 60 Co (0.5 Gy.min -1 ) up to 4 Gy and the PCC technique was performed after 24 h, 48 h, and 72 h of DNA repair at 37 deg. C. Analysis of excess PCC fragments distribution showed an overdispersion and the dose-effect relationship was best characterised by linear regression. Radiation-induced damage was reduced to 32% between the first and the second day of repair and to 42% the following day. Statistical precision of the dose was found to be dependent on the irradiation dose and on the number of cells examined. The necessity to establish dose-response relationships after different periods of DNA repair is demonstrated, and the use of PCC excess fragments yield as a bioindicator should take this fact into account. (author)

  5. A study on the characteristics of enamel to electron spin resonance spectrum for retrospective dosimetry

    International Nuclear Information System (INIS)

    Hong, Dae Seok; Lee, Kun Jai

    2003-01-01

    Electron Spin Resonance (ESR) spectroscopy is one of the methods applicable to retrospective dosimetry. The retrospective dosimetry is a part of dose reconstruction for estimation of exposed dose occurred years before the estimation. A tooth can be separated as enamel, dentine and cementum. Among the three parts, enamel is known as to show the best sensitivity to the absorbed dose and is most widely used. Since the later 80s, ESR dosimetry with tooth enamel has been studied and applied for the retrospective dosimetry. There are some factors affecting the sensitivity of enamel to absorbed dose. One of the factors is a size of enamel. Grain size of the 1.0mm∼0.1mm range is commonly used and 0.6mm∼0.25mm is recommended in other study. But the sensitivity can be varied by the grain size. In this study, the granular effect of enamel to the sensitivity is examined for application to retrospective dosimetry. In the enamel separation, to minimize the physically induced ESR spectrum, only chemical separation method was used. Separated enamels were divided by their size. The sizes of each sample is 1.0mm∼0.71mm, 0.5mm∼0.3mm, and below 0.1mm, respectively. All enamel samples show ESR spectrum related to the absorbed dose and the ESR spectrum shows linearity to the absorbed dose. The sensitivities are similar for each sample. But the enamel of size below 0.1mm shows poor characteristics relative to other enamel size. So, it is not recommended to use enamel samples below 0.1mm

  6. Synthesis, biological distribution and radiation dosimetry of Te-123m analogues of hexadecenoic acid

    International Nuclear Information System (INIS)

    Basmadjian, G.P.; Ice, R.D.; Mills, S.L.

    1982-01-01

    The synthesis and biological distribution of four Te-123m analogues of hexadecenoic acid in rats, rabbits and dogs were described for use as possible myocardial imaging agents. The heart-to-blood ratios ranged from 0.13 for 3-telluranonadecenoic acid in rats at 5 mins to 6.25 for 18-methyl-17-tellura-9-nonadecenoic acid in dogs at 24 hrs. The biological half-life of the Te-123m labelled fatty acids ranged from 26 to 583 hrs in the hearts of the test animals. These Te-123m fatty acids were retained in the heart longer than radioiodinated fatty acids and have acceptable absorbed doses to the various target organs. (U.K.)

  7. Monte Carlo verification of polymer gel dosimetry applied to radionuclide therapy: a phantom study

    International Nuclear Information System (INIS)

    Gear, J I; Partridge, M; Flux, G D; Charles-Edwards, E

    2011-01-01

    This study evaluates the dosimetric performance of the polymer gel dosimeter 'Methacrylic and Ascorbic acid in Gelatin, initiated by Copper' and its suitability for quality assurance and analysis of I-131-targeted radionuclide therapy dosimetry. Four batches of gel were manufactured in-house and sets of calibration vials and phantoms were created containing different concentrations of I-131-doped gel. Multiple dose measurements were made up to 700 h post preparation and compared to equivalent Monte Carlo simulations. In addition to uniformly filled phantoms the cross-dose distribution from a hot insert to a surrounding phantom was measured. In this example comparisons were made with both Monte Carlo and a clinical scintigraphic dosimetry method. Dose-response curves generated from the calibration data followed a sigmoid function. The gels appeared to be stable over many weeks of internal irradiation with a delay in gel response observed at 29 h post preparation. This was attributed to chemical inhibitors and slow reaction rates of long-chain radical species. For this reason, phantom measurements were only made after 190 h of irradiation. For uniformly filled phantoms of I-131 the accuracy of dose measurements agreed to within 10% when compared to Monte Carlo simulations. A radial cross-dose distribution measured using the gel dosimeter compared well to that calculated with Monte Carlo. Small inhomogeneities were observed in the dosimeter attributed to non-uniform mixing of monomer during preparation. However, they were not detrimental to this study where the quantitative accuracy and spatial resolution of polymer gel dosimetry were far superior to that calculated using scintigraphy. The difference between Monte Carlo and gel measurements was of the order of a few cGy, whilst with the scintigraphic method differences of up to 8 Gy were observed. A manipulation technique is also presented which allows 3D scintigraphic dosimetry measurements to be compared to polymer

  8. Reference dosimetry and small-field dosimetry in external beam radiotherapy: Results from a Danish intercomparison study

    DEFF Research Database (Denmark)

    Beierholm, Anders Ravnsborg; Behrens, Claus F.; Sibolt, Patrik

    methods was performed by DTU Nutech at six Danish clinics. The first part of the intercompa-rison regarded the consistency of reference dosimetry. Absorbed dose to water under reference conditions was measured using a Farmer ionization chamber, and was found to agree within 1 % with the daily dose checks......-specific correction factors for non-reference fields....

  9. OEDIPE, a software for personalized Monte Carlo dosimetry and treatment planning optimization in nuclear medicine: absorbed dose and biologically effective dose considerations

    International Nuclear Information System (INIS)

    Petitguillaume, A.; Broggio, D.; Franck, D.; Desbree, A.; Bernardini, M.; Labriolle Vaylet, C. de

    2014-01-01

    For targeted radionuclide therapies, treatment planning usually consists of the administration of standard activities without accounting for the patient-specific activity distribution, pharmacokinetics and dosimetry to organs at risk. The OEDIPE software is a user-friendly interface which has an automation level suitable for performing personalized Monte Carlo 3D dosimetry for diagnostic and therapeutic radionuclide administrations. Mean absorbed doses to regions of interest (ROIs), isodose curves superimposed on a personalized anatomical model of the patient and dose-volume histograms can be extracted from the absorbed dose 3D distribution. Moreover, to account for the differences in radiosensitivity between tumoral and healthy tissues, additional functionalities have been implemented to calculate the 3D distribution of the biologically effective dose (BED), mean BEDs to ROIs, isoBED curves and BED-volume histograms along with the Equivalent Uniform Biologically Effective Dose (EUD) to ROIs. Finally, optimization tools are available for treatment planning optimization using either the absorbed dose or BED distributions. These tools enable one to calculate the maximal injectable activity which meets tolerance criteria to organs at risk for a chosen fractionation protocol. This paper describes the functionalities available in the latest version of the OEDIPE software to perform personalized Monte Carlo dosimetry and treatment planning optimization in targeted radionuclide therapies. (authors)

  10. Concerted Uranium Research in Europe (CURE): toward a collaborative project integrating dosimetry, epidemiology and radiobiology to study the effects of occupational uranium exposure.

    Science.gov (United States)

    Laurent, Olivier; Gomolka, Maria; Haylock, Richard; Blanchardon, Eric; Giussani, Augusto; Atkinson, Will; Baatout, Sarah; Bingham, Derek; Cardis, Elisabeth; Hall, Janet; Tomasek, Ladislav; Ancelet, Sophie; Badie, Christophe; Bethel, Gary; Bertho, Jean-Marc; Bouet, Ségolène; Bull, Richard; Challeton-de Vathaire, Cécile; Cockerill, Rupert; Davesne, Estelle; Ebrahimian, Teni; Engels, Hilde; Gillies, Michael; Grellier, James; Grison, Stephane; Gueguen, Yann; Hornhardt, Sabine; Ibanez, Chrystelle; Kabacik, Sylwia; Kotik, Lukas; Kreuzer, Michaela; Lebacq, Anne Laure; Marsh, James; Nosske, Dietmar; O'Hagan, Jackie; Pernot, Eileen; Puncher, Matthew; Rage, Estelle; Riddell, Tony; Roy, Laurence; Samson, Eric; Souidi, Maamar; Turner, Michelle C; Zhivin, Sergey; Laurier, Dominique

    2016-06-01

    The potential health impacts of chronic exposures to uranium, as they occur in occupational settings, are not well characterized. Most epidemiological studies have been limited by small sample sizes, and a lack of harmonization of methods used to quantify radiation doses resulting from uranium exposure. Experimental studies have shown that uranium has biological effects, but their implications for human health are not clear. New studies that would combine the strengths of large, well-designed epidemiological datasets with those of state-of-the-art biological methods would help improve the characterization of the biological and health effects of occupational uranium exposure. The aim of the European Commission concerted action CURE (Concerted Uranium Research in Europe) was to develop protocols for such a future collaborative research project, in which dosimetry, epidemiology and biology would be integrated to better characterize the effects of occupational uranium exposure. These protocols were developed from existing European cohorts of workers exposed to uranium together with expertise in epidemiology, biology and dosimetry of CURE partner institutions. The preparatory work of CURE should allow a large scale collaborative project to be launched, in order to better characterize the effects of uranium exposure and more generally of alpha particles and low doses of ionizing radiation.

  11. Measurement assurance studies of high-energy electron and photon dosimetry in radiation-therapy applications

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlich, M; Soares, C G [National Bureau of Standards, Washington, DC (USA)

    1981-08-01

    This is a brief review of surveys on the dosimetry of radiation-therapy beams by the National Bureau of Standards (NBS). Covered are the NBS ferrous-sulfate (Fricke) dosimetry service, a recently completed survey carried out with thermoluminescence dosimeters (TLD) on the dosimetry in cobalt-60 teletherapy beams, and plans for a TLD survey of dosimetry in high-energy bremsstrahlung beams.

  12. Estimation of dose ionizing radiation exposure by biological dosimetry; Estimación de dosis de exposición a radiaciones ionizantes mediante dosimetría biológica

    Energy Technology Data Exchange (ETDEWEB)

    Herranz Crespo, R.; Moreno Domene, M.; Prieto Rodríguez, M.J.; Lozano Barriuso, M.A.

    2014-07-01

    the Biological Dosimetry Laboratory of the Radiopathology Centre, at Hospital General Universitario Gregorio Marañón, is the only national laboratory accredited by UNE-EN ISO/IEC 17025:2005, and scope to ISO 19238:2004 (Radiation protection – Performance criteria for service laboratories performing biological dosimetry by citogenetics), for dose assessment by the dycentrics assay, has great experience with more than 100 real cases analyzed, and several population studies. This paper describes experience and results from more than 20 years of work under the Reference level II Centre for the attention of irradiated and/or contaminated people. [Spanish] El Laboratorio de Dosimetría Biológica, del Centro de Radiopatología del Hospital General Universitario Gregorio Marañón, es el único en España que dispone de acreditación internacional por la norma UNE-EN ISO/IEC 17025:2005 con alcance a la norma ISO 19238:2004 (Radiationprotection – Performance criteria for service laboratories performing biological dosimetry by citogenetics), para la realización de estimaciones dosimétricas mediante la técnica de dicéntricos, dispone de amplia experiencia en su aplicación en los 110 casos reales analizados, y en diferentes estudios de poblaciones españolas. En este trabajo se describe la experiencia del laboratorio y los resultados obtenidos en los más de 20 años de funcionamiento en el Centro de Referencia de nivel II para la atención a irradiados y/o contaminados por radiaciones ionizantes.

  13. Cytogenetic biological dosimetry in radiological protection: chromosome aberration analysis in human lymphocyties

    International Nuclear Information System (INIS)

    Campos, I.M.A. de.

    1988-01-01

    The effects of ionizing radiation on chromosomes have been know for several decades and dose effect relationships are also fairly well established for several doses and dose rates. Apart from its biological significance, the interpretation of chromosome aberration frequency associated with human exposure to radiation plays an important role in dose assessment, particularly in cases where exposure is though to have occurred but no physical dose monitoring system was present. Based on the cytogenetic data obtained from seven cases of exposure to radiation the aberration frequency have been fitted to the quadratic function Y= αD + βD 2 as the dose response curves from literature. The dose equivalent estimate by frequency of chromosomic aberration found here was compared with 60 Co and 192 Ir already published curves obtained at almost similar dose rate together with some hematological data. (author) [pt

  14. Development and performance evaluation of a dynamic phantom for biological dosimetry of moving targets

    Science.gov (United States)

    Gemmel, A.; Bert, C.; Saito, N.; von Neubeck, C.; Iancu, G.; K-Weyrather, W.; Durante, M.; Rietzel, E.

    2010-06-01

    A dynamic phantom has been developed to allow for measurement of 3D cell survival distributions and the corresponding distributions of the RBE-weighted dose (RBED) in the presence of motion. The phantom consists of two 96-microwell plates holding Chinese hamster ovary cells inside a container filled with culture medium and is placed on a movable stage. Basic biological properties of the phantom were investigated without irradiation and after irradiation with a carbon ion beam, using both a stationary (reference) exposure and exposure during motion of the phantom perpendicular to the beam with beam tracking. There was no statistically significant difference between plating efficiency measured in the microwells with and without motion (0.75) and values reported in the literature. Mean differences between measured and calculated cell survival for these two irradiation modes were within ±5% of the target dose of 6 Gy (RBE).

  15. Development and performance evaluation of a dynamic phantom for biological dosimetry of moving targets

    Energy Technology Data Exchange (ETDEWEB)

    Gemmel, A; Bert, C; Saito, N; Von Neubeck, C; Iancu, G; K-Weyrather, W; Durante, M; Rietzel, E, E-mail: alexander.ag.gemmel@siemens.co [GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstr 1, 64291 Darmstadt (Germany)

    2010-06-07

    A dynamic phantom has been developed to allow for measurement of 3D cell survival distributions and the corresponding distributions of the RBE-weighted dose (RBED) in the presence of motion. The phantom consists of two 96-microwell plates holding Chinese hamster ovary cells inside a container filled with culture medium and is placed on a movable stage. Basic biological properties of the phantom were investigated without irradiation and after irradiation with a carbon ion beam, using both a stationary (reference) exposure and exposure during motion of the phantom perpendicular to the beam with beam tracking. There was no statistically significant difference between plating efficiency measured in the microwells with and without motion (0.75) and values reported in the literature. Mean differences between measured and calculated cell survival for these two irradiation modes were within {+-}5% of the target dose of 6 Gy (RBE).

  16. Stopping powers for protons in materials of interest in dosimetry and in medical and biological applications

    International Nuclear Information System (INIS)

    Thwaites, D.I.

    1985-01-01

    Stopping powers are required for many radiation applications in medicine and biology. Their accuracy can be critical. Some published calculations for these situations have not included recent developments in stopping power theory or the body of work on deviations from additivity due to phase of chemical binding effects. These areas have recently been reviewed and mean excitation energies recommended for a range of materials of interest. Calculated stopping powers are presented for protons of 0.4 to 200 MeV taking the available information into account. The materials considered are Lucite, ICRU composition muscle and bone, A-150 plastic, a TE gas, acetylene and polystyrene and water and water vapour. With suitable corrections and suitable I values in the Bethe stopping power expression, accuracies of <2% can be achieved. (author)

  17. Biological study in schizophrenia

    International Nuclear Information System (INIS)

    Kasai, Kiyoto; Yoshikawa, Akane; Natsubori, Takanobu; Koike, Shinsuke; Nagai, Tatsuya; Araki, Tsuyoshi; Nishimura, Yukika; Iwamoto, Kazuya

    2012-01-01

    Schizophrenia is associated with enormous morbidity, mortality, personal disability, and social cost. Although considerable research on schizophrenia has been performed, the etiology of this disease has not been fully elucidated. In recent years, imaging and genetic technologies have been developed dramatically. Disturbances in glutamate and gamma-aminobutyric acid (GABA)ergic neurotransmission may underlie the pathophysiology of schizophrenia. We attempted an integrative review, of studies pertaining to recent advances of schizophrenia research with a focus on neuroimaging and genetic studies. Additionally, we present the preliminary findings of the clinical research in our outpatient unit, specialized for early intervention, at the University of Tokyo Hospital. (author)

  18. Biological dosimetry of local radiation accidents of skin: possible cytological and biochemical methods

    International Nuclear Information System (INIS)

    Potten, C.S.

    1986-01-01

    Skin erythema or skin reaction is a highly dose-dependent change in skin appearance. A few gray can usually be detected in humans but higher doses are usually required for experimental rodents. The disadvantages are that the end-point is subjective and the response strongly influenced by numerous physical and biological factors. Changes in the levels of pigmentation can be detected in the epidermis and possibly the hair follicles but generally these only become apparent after chronic exposures. The skin appendages, particularly the hair follicles, could represent sensitive systems for detecting radiation exposures, but the cyclic behaviour of the hair follicles is difficult to control or determine in an accident. Acute cell death can be measured in the follicle germ and changes in the thickness and appearance of the hair are easily detected: in severe cases there is loss of hair (epilation). The number of dead cells per follicle section increased at a rate of 2.9/Gy and doses of about 0.2Gy can be easily detected. The width of the hair is reduced by about 7-8%/Gy and this change, which results in a dysplastic hair is believed to be the consequences of cell death in the follicles. (author)

  19. Advances in biomedical dosimetry

    International Nuclear Information System (INIS)

    1981-01-01

    Full text: Radiation dosimetry, the accurate determination of the absorbed dose within an irradiated body or a piece of material, is a prerequisite for all applications of ionizing radiation. This has been known since the very first radiation applications in medicine and biology, and increasing efforts are being made by radiation researchers to develop more reliable, effective and safe instruments, and to further improve dosimetric accuracy for all types of radiation used. Development of new techniques and instrumentation was particularly fast in the field of both medical diagnostic and therapeutic radiology. Thus, in Paris in October the IAEA held the latest symposium in its continuing series on dosimetry in medicine and biology. The last one was held in Vienna in 1975. High-quality dosimetry is obviously of great importance for human health, whether the objectives lie in the prevention and control of risks associated with the nuclear industry, in medical uses of radioactive substances or X-ray beams for diagnostic purposes, or in the application of photon, electron or neutron beams in radiotherapy. The symposium dealt with the following subjects: General aspects of dosimetry; Special physical and biomedical aspects; Determination of absorbed dose; Standardization and calibration of dosimetric systems; and Development of dosimetric systems. The forty or so papers presented and the discussions that followed them brought out a certain number of dominant themes, among which three deserve particular mention. - The recent generalization of the International System of Units having prompted a fundamental reassessment of the dosimetric quantities to be considered in calibrating measuring instruments, various proposals were advanced by the representatives of national metrology laboratories to replace the quantity 'exposure' (SI unit = coulomb/kg) by 'Kerma' or 'absorbed dose' (unit joule/kg, the special name of which is 'gray'), this latter being closer to the practical

  20. Biological Sampling Variability Study

    Energy Technology Data Exchange (ETDEWEB)

    Amidan, Brett G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hutchison, Janine R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-11-08

    There are many sources of variability that exist in the sample collection and analysis process. This paper addresses many, but not all, sources of variability. The main focus of this paper was to better understand and estimate variability due to differences between samplers. Variability between days was also studied, as well as random variability within each sampler. Experiments were performed using multiple surface materials (ceramic and stainless steel), multiple contaminant concentrations (10 spores and 100 spores), and with and without the presence of interfering material. All testing was done with sponge sticks using 10-inch by 10-inch coupons. Bacillus atrophaeus was used as the BA surrogate. Spores were deposited using wet deposition. Grime was coated on the coupons which were planned to include the interfering material (Section 3.3). Samples were prepared and analyzed at PNNL using CDC protocol (Section 3.4) and then cultured and counted. Five samplers were trained so that samples were taken using the same protocol. Each sampler randomly sampled eight coupons each day, four coupons with 10 spores deposited and four coupons with 100 spores deposited. Each day consisted of one material being tested. The clean samples (no interfering materials) were run first, followed by the dirty samples (coated with interfering material). There was a significant difference in recovery efficiency between the coupons with 10 spores deposited (mean of 48.9%) and those with 100 spores deposited (mean of 59.8%). There was no general significant difference between the clean and dirty (containing interfering material) coupons or between the two surface materials; however, there was a significant interaction between concentration amount and presence of interfering material. The recovery efficiency was close to the same for coupons with 10 spores deposited, but for the coupons with 100 spores deposited, the recovery efficiency for the dirty samples was significantly larger (65

  1. Experimental and computational development of a natural breast phantom for dosimetry studies

    International Nuclear Information System (INIS)

    Nogueira, Luciana B.; Campos, Tarcisio P.R.

    2013-01-01

    This paper describes the experimental and computational development of a natural breast phantom, anthropomorphic and anthropometric for studies in dosimetry of brachytherapy and teletherapy of breast. The natural breast phantom developed corresponding to fibroadipose breasts of women aged 30 to 50 years, presenting radiographically medium density. The experimental breast phantom was constituted of three tissue-equivalents (TE's): glandular TE, adipose TE and skin TE. These TE's were developed according to chemical composition of human breast and present radiological response to exposure. Completed the construction of experimental breast phantom this was mounted on a thorax phantom previously developed by the research group NRI/UFMG. Then the computational breast phantom was constructed by performing a computed tomography (CT) by axial slices of the chest phantom. Through the images generated by CT a computational model of voxels of the thorax phantom was developed by SISCODES computational program, being the computational breast phantom represented by the same TE's of the experimental breast phantom. The images generated by CT allowed evaluating the radiological equivalence of the tissues. The breast phantom is being used in studies of experimental dosimetry both in brachytherapy as in teletherapy of breast. Dosimetry studies by MCNP-5 code using the computational model of the phantom breast are in progress. (author)

  2. Twenty-first nuclear accident dosimetry intercomparison study, August 6-10, 1984

    International Nuclear Information System (INIS)

    Swaja, R.E.; Ragan, G.E.; Sims, C.S.

    1985-05-01

    The twenty-first in a series of nuclear accident dosimetry (NAD) intercomparison (NAD) studies was conducted at the Oak Ridge National Laboratory's Dosimetry Applications Research Facility during August 6-10, 1984. The Health Physics Research Reactor operated in the pulse mode was used to simulate three criticality accidents with different radiation fields. Participants from five organizations measured neutron doses between 0.53 and 4.36 Gy and gamma doses between 0.19 and 1.01 Gy at area monitoring stations and on phantoms. About 75% of all neutron dose estimates based on foil activation, hair activation, simulated blood sodium activation, and thermoluminescent methods were within +-25% of reference values. Approximately 86% of all gamma results measured using thermoluminescent (TLD-700 or CaSO 4 ) systems were within +-20% of reference doses which represents a significant improvement over previous studies. Improvements observed in the ability of intercomparison participants to estimate neutron and gamma doses under criticality accident conditions can be partly attributed to experience in previous NAD studies which have provided practical tests of dosimetry systems, enabled participants to improve evaluation methods, and standardized dose reporting conventions. 16 refs., 15 tabs

  3. Basic study on electrically stimulated luminescence (ESL) as a dosimetry and dating method

    International Nuclear Information System (INIS)

    Sato, H.; Yamanaka, C.; Ikeya, M.

    2003-01-01

    Electrically stimulated luminescence (ESL) of calcium carbonate has been studied for application as dosimetry and dating. A powdered calcium carbonate was sandwiched by electrodes, which supplied electric field. Luminescence and surface current through a powdered sample were measured using a photomultiplier and a digital multimeter, respectively. A linear dependence of ESL on the absorbed dose by γ-rays was found when the applied voltage was below the breakdown threshold. Reciprocal electric charges through the sample had also linear relation with the absorbed dose. We propose that the luminescence and electric charge under intense electric field in calcium carbonate become new methods for dosimetry and dating on the basis of the surface defects of the calcium carbonate grains produced by the irradiation of γ-rays

  4. Study of a new glass matrix by thermoluminescent technique for high-dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Pamela Z.; Carvalho, Gabriel S. Marchiori de; Cunha, Diego M. da; Dantas, Noelio O.; Silva, Anielle C.A.; Neves, Lucio P.; Perini, Ana P., E-mail: anapaula.perini@ufu.br [Universidade Federal de Uberlandia (UFU), MG (Brazil). Instituto de Fisica; Linda, V.E. Caldas [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Carrera, Betzabel N.S.; Watanabe, Shigueo [Universidade de Sao Paulo (IF/USP), Sao Paulo, SP (Brazil). Instituto de Fisica

    2016-07-01

    The thermoluminescence technique is widely used for both personal and for high-dose dosimetry. In this work, the thermoluminescence technique was utilized to study a new glass matrix, with nominal composition of 20Li{sub 2}CO{sub 3}.10Al{sub 2}O{sub 3}.30BaO.40B{sub 2}O{sub 3} (mol%), irradiated with different doses in a {sup 60}Co source. The glow curves and the dose-response curve were obtained for radiation doses of 10, 50, 100, 200 e 700 Gy. The results showed that this new glass matrix has potential use in high-dose dosimetry. (author)

  5. A study on depth-scaling of plastic phantom in electron beam dosimetry

    International Nuclear Information System (INIS)

    Kojima, T.; Saitoh, H.; Kawachi, T.; Katayose, T.; Myojyoyama, A.

    2005-01-01

    In recommendations of several standard dosimetry, water is defined as the reference medium, however, the water substitute plastic phantoms are highly discouraged. Nevertheless, in the case of accurate chamber positioning in water is not possible, or no waterproof chamber is available, their use is permitted at beam qualities R 50 2 (E 0 pl obtained from a ratio of electron average penetration depth; z av , half value depth ratio; (R 50 ) w,m from Monte Carlo dose calculation and that from measurements, are compared each other. As a result, there are slight differences in depth-scaling factor between obtained from simulation results and from measurements. These results indicate that c pl has to be studied more detail for the sake of precise electron dosimetry in plastic phantoms. (author)

  6. Nuclear accident dosimetry

    International Nuclear Information System (INIS)

    1982-01-01

    The film presents statistical data on criticality accidents. It outlines past IAEA activities on criticality accident dosimetry and the technical documents that resulted from this work. The film furthermore illustrates an international comparison study on nuclear accident dosimetry conducted at the Atomic Energy Research Establishment, Harwell, United Kingdom

  7. Nuclear accident dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-12-31

    The film presents statistical data on criticality accidents. It outlines past IAEA activities on criticality accident dosimetry and the technical documents that resulted from this work. The film furthermore illustrates an international comparison study on nuclear accident dosimetry conducted at the Atomic Energy Research Establishment, Harwell, United Kingdom

  8. Study of Optically Stimulated Luminescence of LiF:Mg,Ti for beta and gamma dosimetry

    International Nuclear Information System (INIS)

    Matsushima, Luciana C.; Veneziani, Glauco R.; Campos, Letícia L.

    2013-01-01

    Modern advances in radiation medicine – radiodiagnosis, radiotherapy and interventional radiography – each present dosimetry challenges for the medical physicist that did not exist previously. In all of these areas a constant balance has to be made between the treatment necessary to destroy the tumor and the unnecessary exposure of healthy tissue. Innovative applications of OSL dosimetry are now appearing in each of these areas to help the medical physicist and oncologist design the most effective, and least deleterious, treatment for their patients. High sensitivity, precise delivery of light, fast readout times, simpler readers and easier automation are the main advantages of OSL in comparison with TLD. This work aimed to study the application of OSL technique using lithium fluoride dosimeters doped with magnesium and titanium (LiF:Mg,Ti) for application in beta and gamma dosimetry. -- Highlights: •Study of Optically Stimulated Luminescence of LiF:Mg,Ti and microLiF:Mg,Ti. •OSL response of TLD-100 dosimeters to beta and gamma radiation. •Analysis of repeatability and lowest levels of detection of detectors LiF:Mg,Ti

  9. How can bio dosimetry measurements be used to improve radiation epidemiologic studies?

    International Nuclear Information System (INIS)

    Simon, Steven L.; Bouville, Andre; Kleinerman, Ruth

    2008-01-01

    Full text: Bio dosimetry measurements can be used potentially to improve radiation epidemiologic studies by providing a means to corroborate analytical or model-based dose estimates, to assess bias in models and their dose estimates, and reduce uncertainty in individual or group-average doses. Radiation epidemiologic studies typically rely on accurate estimation of doses to the whole body or to specific organs for numerous individuals in order to derive reliable estimates of risk of cancer or other medical conditions. However, dose estimates whether based on analytical dose reconstruction (i.e., models) or personnel monitoring measurements, e.g., film-badges, are associated with considerable and varying degrees of uncertainty. Uncertainty is a product of many factors; persons were exposed many years or decades earlier and usually only inadequate data or measurements are available. While bio dosimetry has begun to play a more significant role in long-term health risk studies, its use is still limited in that context, primarily due sometimes to inadequate limits of detection, inter-individual variability of the signal measured, and high per-sample cost. Presently, the most suitable bio dosimetry methods for epidemiologic studies are chromosome aberration frequencies from fluorescence in situ hybridization (FISH) of peripheral blood lymphocytes and electron paramagnetic resonance (EPR) measurements made on tooth enamel, with detection limits of approximately 0.3 to 0.5 Gy, and as low as 0.03 Gy for FISH and EPR, respectively. Presently, both methods are invasive and require obtaining either blood or teeth. Though both FISH and EPR have been used in a variety of large long-term health risk studies including those of a-bomb survivors and various occupational and environmental exposures, only recently has considerable thought been given to how these data can be used in epidemiologic studies in any but rudimentary ways. Key issues to consider are the representativeness of

  10. Chromosomal analysis and application of biological dosimetry in two cases of apparent over exposure; Analisis cromosomico y aplicacion de la dosimetria biologica en dos casos de aparente sobreexposicion

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero C, C.; Brena V, M. [Departamento de Biologia, ININ A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The gamma radiation calibration curve of {sup 60} Co is used which was generated in the ININ Laboratory of Biology to calculate the exposure dose of two workers whose dosemeters marked values above of the limit allowed. The analysis indicates that in a first case, the aberrations frequency corresponded to the basal value, therefore there is not over exposure. The aberrations frequency of the second case is lightly above to the basal value and therefore the probability favors to what the physical dosimetry indicates. (Author)

  11. Evaluation of DNA dosimetry to assess ozone-mediated variability of biologically harmful radiation in Antarctica

    NARCIS (Netherlands)

    George, AL; Peat, HJ; Buma, AGJ

    In this study we investigated the use of a DNA dosimeter to accurately measure changes in ultraviolet B radiation (UVBR; 280-315 nm) under Antarctic ozone hole conditions. Naked DNA solution in quartz tubes was exposed to ambient solar radiation at Rothera Research Station, Antarctica, between

  12. Study for applying microwave power saturation technique on fingernail/EPR dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byeong Ryong; Choi, Hoon; Nam, Hyun Ill; Lee, Byung Ill [Radiation Health Research Institute, Seoul (Korea, Republic of)

    2012-10-15

    There is growing recognition worldwide of the need to develop effective uses of dosimetry methods to assess unexpected exposure to radiation in the event of a large scale event. One of physically based dosimetry methods electron paramagnetic resonance (EPR) spectroscopy has been applied to perform retrospective radiation dosimetry using extracted samples of tooth enamel and nail(fingernail and toenail), following radiation accidents and exposures resulting from weapon use, testing, and production. Human fingernails are composed largely of a keratin, which consists of {alpha} helical peptide chains that are twisted into a left handed coil and strengthened by disulphide cross links. Ionizing radiation generates free radicals in the keratin matrix, and these radicals are stable over a relatively long period (days to weeks). Most importantly, the number of radicals is proportional to the magnitude of the dose over a wide dose range (0{approx}30 Gy). Also, dose can be estimated at four different locations on the human body, providing information on the homogeneity of the radiation exposure. And The results from EPR nail dosimetry are immediately available However, relatively large background signal (BKS) converted from mechanically induced signal (MIS) after cutting process of fingernail, normally overlaps with the radiation induced signal (RIS), make it difficult to estimate accurate dose accidental exposure. Therefore, estimation method using dose response curve was difficult to ensure reliability below 5 Gy. In this study, In order to overcome these disadvantages, we measured the reactions of RIS and BKS (MIS) according to the change of Microwave power level, and researched about the applicability of the Power saturation technique at low dose.

  13. Dosimetry Control: Technic and methods. Proceedings of the international workshop 'Actual problems of dosimetry'

    International Nuclear Information System (INIS)

    Lyutsko, A.M.; Nesterenko, V.B.; Chudakov, V.A.; Konoplya, E.F.; Milyutin, A.A.

    1997-10-01

    There is a number of unsolved problems of both dosimetric and radiometric control, questions of the biological dosimetry, reconstruction of dozes of irradiation of the population at radiation incidents, which require coordination of efforts of scientists in various areas of a science. The submitted materials are grouped on five units: dosimetry engineering, biological dosimetry and markers of radiation impact, dosimetry of a medical irradiation, normative and measurement assurance of the dosimetric control, monitoring and reconstruction of dozes at radiation incidents

  14. Biological and clinical dosimetry. Progress report, October 1, 1977--September 30, 1978

    International Nuclear Information System (INIS)

    Laughlin, J.S.; McDonald, J.C.

    1978-01-01

    The portable tissue equivalent plastic calorimeter has been employed for a number of studies including: measurements of neutron dose in therapeutic beams and the measurement of dose in photon and electron beams. Measurements of the thermal defect for A-150 plastic have been carried out using 1.7 and 4.0 MeV protons produced by the Brookhaven National Laboratory, Van de Graaf accelerator. Initial results do not indicate significant energy dependence and the values obtained so far are within about 1% of the estimated value for the thermal defect. Microdosimetric studies were continued, and the distribution of dose in lineal energy was measured at the Texas A and M cyclotron for 50 MeV deuterons incident on a beryllium target

  15. Dosimetry Service

    CERN Multimedia

    2006-01-01

    Cern Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page: http://cern.ch/rp-dosimetry Dosimetry Service is open every morning from 8.30 - 12.00. Closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after the use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel. 7 2155 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  16. Development of the FISH technique for biological dosimetry applications in the Gregorio Maranon General University Hospital

    International Nuclear Information System (INIS)

    Moreno, M.; Jesus Prieto, M.; Olivares, P.; Gomez, M.; Herranz, R.

    1997-01-01

    Since 1989 cytogenetic analysis for dose estimation has been regularly used In the Gregorio Maranon General University Hospital (HGUGM) of Madrid on individuals suspected of having accidentally been exposed to ionizing radiation. The method used is the study of chromosomal aberrations found in lymphocytes of peripheral blood. The technique recommended by the IAEA in 1986 permits to establish a dicentrics/dose ratio through an effective dose calibration curve prepared in-vitro. This methodology of dose estimation presents serious limitations which can partially be eliminated by means of new molecular cytogenetic techniques, such as chromosomal painting through in-situ hybridization with fluorescence (FISH). At HGUGM, research work has been finished for standardization of the above mentioned technique including effective dose calibration curves, the utilization of adequate aberrations and the intercomparision of the results with other centres

  17. Dosimetry in radiotherapy. V.1

    International Nuclear Information System (INIS)

    1988-01-01

    A series of symposia on dosimetry in medicine and biology have been held by the IAEA in co-operation with WHO. The present symposium was the first one focusing on ''Dosimetry in Radiotherapy''. The papers presented reflected the different steps in the calibration chain such as the calibration standards established by the National Standards Laboratories and the conversion of the reading of calibrated instruments to the desired quantity, i.e. absorbed dose to water at a reference point in the user's beam at the radiotherapy clinic. The programme further examined the procedures necessary for optimization of the treatment of the patient, such as treatment planning methods, dose distribution studies, new techniques of dose measurement, improvements in the physical dose distributions/conformation therapy and special problems involved in total body treatments. Results of quality assurance in radiotherapy were presented from local hospitals as well as from national and international studies. Refs, figs and tabs

  18. Biological Dosimetry Using Micronucleus Assay in Simulated Partial-Body Exposure to Ionizing Radiation

    Directory of Open Access Journals (Sweden)

    S. Purnami

    2017-08-01

    Full Text Available In radiation accidents, it is common that only several parts of the body are exposed to radiation. As a consequence there is a mixture of exposed and unexposed lymphocytes in peripheral blood cells of the samples. This phenomenon will cause the dose value estimated using the exposed lymphocytes to be lower than the actual dose. In this study, an assessment of partial body exposures using micronucleus assay by estimating the partial body dose and fraction of irradiated blood was conducted. An optimal D0 value also has been determined in this study to estimate the fraction of irradiated cells. Peripheral blood lymphocytes (PBLs from three healthy donors were irradiated in vitro with 2 Gy of X-rays. Partial radiation exposure was simulated by mixing the irradiated and non-irradiated blood in different proportions. The proportions of mixtures of blood samples irradiated in vitro were 5, 10, 15, 20, and 30 %. Blood samples were then cultured and harvested based on micronuclei assay protocol. At least 2000 binucleated cells with well-preserved cytoplasm were scored for the MN frequency. Dose Estimate 5.1 software was used to calculate the dispersion index (σ2/y and normalized unit of this index (U in each proportion of bloods. The fractions of irradiated cells were calculated with CABAS (Chromosomal Aberration Calculation Software for several different D0 values (2.7; 3.8; 5.4. The results showed that D0 value at 5.4 gave the closest results to the actual proportion of irradiated bloods, while for the dose estimation the estimated doses value from all proportions in all donors were higher than the actual dose. The factor that may cause this phenomenon was that the dose response calibration curve used to predict the radiation dose was not constructed in the laboratory used. Overall it can be concluded that a biodosimetry using MN assay can be used to estimate the radiation dose in partial body exposure. In order to establish a biodosimetry using MN

  19. Biological and clinical dosimetry. Comprehensive eighteen-year report, July 1, 1964-June 30, 1982

    International Nuclear Information System (INIS)

    Laughlin, J.S.; Zeitz, L.

    1982-01-01

    The objectives are to develop and apply primary and secondary dosimetric systems for measurements in the complex radiation fields currently in use for radiobiological research and advanced radiation oncology. The concept of local absorbed dose calorimetry continues to be applied and further developed using tissue equivalent and other materials. Aspects of a simplified approach to calorimetry with thermistors used as non-isolated-sensors in polystyrene are described. This approach also has the potential of giving accurate absolute absorbed dose measurements in situations where the irradiation time can be limited to about 20 minutes. A non-isolated-sensor calorimeter has also been constructed of A-150 tissue equivalent (TE) plastic. Comparison of the absorbed dose measurements with these two calorimeters, after correction for the known mass energy absorption coefficients, gives a direct determination of the thermal defect of A-150 plastic at different levels of free O 2 content in the material. This will permit a study of various approaches to excluding oxygen. This type of calorimeter is presently also being constructed with solid-water-equivalent plastic, i.e., the material designated WT/SRI by Constantinou. Our previously successful isolated sensor calorimeters are still in operation. With the availability of both isolated and non-isolated absorbed dose calorimeters, of our parallel plate ionization chambers in similar material and geometry, and of specific commercial ion chambers, we are in a unique position not only to compare all of these systems but to examine critically basic assumptions in absorbed dose concepts and the correction factors used in different methodologies

  20. Measurement assurance studies of high-energy electron and photon dosimetry in radiation-therapy applications

    International Nuclear Information System (INIS)

    Ehrlich, M.; Soares, C.G.

    1981-01-01

    This is a brief review of surveys on the dosimetry of radiation-therapy beams by the National Bureau of Standards (NBS). Covered are the NBS ferrous-sulfate (Fricke) dosimetry service, a recently completed survey carried out with thermoluminescence dosimeters (TLD) on the dosimetry in cobalt-60 teletherapy beams, and plans for a TLD survey of dosimetry in high-energy bremsstrahlung beams. (author)

  1. Neutron Dosimetry

    International Nuclear Information System (INIS)

    Vanhavere, F.

    2001-01-01

    The objective of SCK-CEN's R and D programme on neutron dosimetry is to improve the determination of neutron doses by studying neutron spectra, neutron dosemeters and shielding adaptations. In 2000, R and D focused on the contiued investigation of the bubble detectors type BD-PND and BDT, in particular their sensitivity and temperature dependence; the updating of SCK-CEN's criticality dosemeter, the investigation of the characteristics of new thermoluminescent materials and their use in neutron dosemetry; and the investigation of neutron shielding

  2. Neutron Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Vanhavere, F

    2001-04-01

    The objective of SCK-CEN's R and D programme on neutron dosimetry is to improve the determination of neutron doses by studying neutron spectra, neutron dosemeters and shielding adaptations. In 2000, R and D focused on the contiued investigation of the bubble detectors type BD-PND and BDT, in particular their sensitivity and temperature dependence; the updating of SCK-CEN's criticality dosemeter, the investigation of the characteristics of new thermoluminescent materials and their use in neutron dosemetry; and the investigation of neutron shielding.

  3. Biological dosimetry in astronauts

    International Nuclear Information System (INIS)

    Durante, M.

    1996-01-01

    Due to the unavoidable presence of ionizing radiation in space, astronauts are classified as radiation workers. I fact, dose rate in space is considerably higher than on earth. Radiation dose absorbed after one day in space is close to the dose received by all natural sources, excluding radon, in one year on earth. Large solar particle events can considerably increase this dose, and could even be life threatening for an inadequately protected crew

  4. Hippocampal dosimetry correlates with the change in neurocognitive function after hippocampal sparing during whole brain radiotherapy: a prospective study

    International Nuclear Information System (INIS)

    Tsai, Ping-Fang; Yang, Chi-Cheng; Chuang, Chi-Cheng; Huang, Ting-Yi; Wu, Yi-Ming; Pai, Ping-Ching; Tseng, Chen-Kan; Wu, Tung-Ho; Shen, Yi-Liang; Lin, Shinn-Yn

    2015-01-01

    Whole brain radiotherapy (WBRT) has been the treatment of choice for patients with brain metastases. However, change/decline of neurocognitive functions (NCFs) resulting from impaired hippocampal neurogenesis might occur after WBRT. It is reported that conformal hippocampal sparing would provide the preservation of NCFs. Our study aims to investigate the hippocampal dosimetry and to demonstrate the correlation between hippocampal dosimetry and neurocognitive outcomes in patients receiving hippocampal sparing during WBRT (HS-WBRT). Forty prospectively recruited cancer patients underwent HS-WBRT for therapeutic or prophylactic purposes. Before receiving HS-WBRT, all participants received a battery of baseline neurocognitive assessment, including memory, executive functions and psychomotor speed. The follow-up neurocognitive assessment at 4 months after HS-WBRT was also performed. For the delivery of HS-WBRT, Volumetric Modulated Arc Therapy (VMAT) with two full arcs and two non-coplanar partial arcs was employed. For each treatment planning, dose volume histograms were generated for left hippocampus, right hippocampus, and the composite hippocampal structure respectively. Biologically equivalent doses in 2-Gy fractions (EQD 2 ) assuming an alpha/beta ratio of 2 Gy were computed. To perform analyses addressing the correlation between hippocampal dosimetry and the change in scores of NCFs, pre- and post-HS-WBRT neurocognitive assessments were available in 24 patients in this study. Scores of NCFs were quite stable before and after HS-WBRT in terms of hippocampus-dependent memory. Regarding verbal memory, the corresponding EQD 2 values of 0, 10, 50, 80 % irradiating the composite hippocampal structure with <12.60 Gy, <8.81, <7.45 Gy and <5.83 Gy respectively were significantly associated with neurocognitive preservation indicated by the immediate recall of Word List Test of Wechsler Memory Scale-III. According to logistic regression analyses, it was noted that

  5. Worldwide bioassay data resources for plutonium/americium internal dosimetry studies

    International Nuclear Information System (INIS)

    Miller, G.; Bertelli, L.; Little, T.; Guilmette, R.; Riddell, T.; Filipy, R.

    2005-01-01

    Full text: Biokinetic models are the scientific underpinning of internal dosimetry. These models describe how materials of interest taken into the body by various routes (for example inhalation) are transported through the body, allowing the modelling of bioassay measurements and the estimation of radiation dose. The International Commission on Radiation Protection (ICRP) publishes biokinetic models for use in internal dosimetry. These models represent the consensus judgement of a committee of experts, based on human and animal data. Nonetheless, it is important to validate biokinetic models using directly applicable data, in a scientifically transparent manner, especially for internal dosimetry research purposes (as opposed to radiation protection), as in epidemiology studies. Two major goals would be to determine individual variations of model parameters for the purpose of assessing this source of uncertainty in internal dose calculations, and to determine values of workplace specific parameters (such as particle solubility in lung fluids) for different representative workplaces. Furthermore, data on the observed frequency of intakes under various conditions can be used in the interpretation of bioassay data. All of the above may be couched in the terminology of Bayesian statistical analysis and amount to the determination of the Bayesian prior probability distributions needed in a Bayesian interpretation of bioassay data. The authors have direct knowledge of several significant databases of plutonium/americium bioassay data (including autopsy data). The purpose of this paper is to acquaint the worldwide community with these resources and to invite others who may know of other such databases to participate with us in a publication that would document the content, form, and the procedures for seeking access to these databases. These databases represent a tremendous scientific resource in this field. Examples of databases known to the authors include: the

  6. Dicentric chromosome aberration analysis using giemsa and centromere specific fluorescence in-situ hybridization for biological dosimetry: An inter- and intra-laboratory comparison in Indian laboratories

    International Nuclear Information System (INIS)

    Bhavani, M.; Tamizh Selvan, G.; Kaur, Harpreet; Adhikari, J.S.; Vijayalakshmi, J.; Venkatachalam, P.; Chaudhury, N.K.

    2014-01-01

    To facilitate efficient handling of large samples, an attempt towards networking of laboratories in India for biological dosimetry was carried out. Human peripheral blood samples were exposed to 60 Co γ-radiation for ten different doses (0–5 Gy) at a dose rate of 0.7 and 2 Gy/min. The chromosomal aberrations (CA) were scored in Giemsa-stained and fluorescence in-situ hybridization with centromere-specific probes. No significant difference (p>0.05) was observed in the CA yield for given doses except 4 and 5 Gy, between the laboratories, among the scorers and also staining methods adapted suggest the reliability and validates the inter-lab comparisons exercise for triage applications. - Highlights: • This is the first report from India on Networking for Biological Dosimetry preparedness using dicentric chromosomal (DC) aberration assay. • There is no significant difference in the in vitro dose response curve (Slope, Intercept, Curvature) constructed among the two labs. • No significant variation in the scoring of DC aberrations between the scorers irrespective of labs. • The DC results obtained by the labs from the Giemsa stained metaphase preparations were confirmed with centromere specific-FISH for further reliability and validity

  7. Cellular dosimetry in nuclear medicine imaging: training

    International Nuclear Information System (INIS)

    Gardin, I.; Faraggi, M.; Stievenart, J.L.; Le Guludec, D.; Bok, B.

    1998-01-01

    The radionuclides used in nuclear medicine imaging emit not only diagnostically useful photons, but also energy electron emissions, responsible for dose heterogeneity at the cellular level. The mean dose delivered to the cell nucleus by electron emissions of 99m Tc, 123 I, 111 In, 67 Ga, and 201 Tl, has been calculated, for the cell nucleus, a cytoplasmic and a cell membrane distribution of radioactivity. This model takes into account both the self-dose which results from the radionuclide located in the target cell, and the cross-dose, which comes from the surrounding cells. The results obtained by cellular dosimetry (D cel ) have been compared with those obtained with conventional dosimetry (D conv ), by assuming the same amount of radioactivity per cell. Cellular dosimetry shows, for a cytoplasmic and a cell membrane distributions of radioactivity, that the main contribution to the dose to the cell nucleus, comes from the surrounding cells. On the other hand, for a cell nucleus distribution of radioactivity, the self-dose is not negligible and may be the main contribution. The comparison between cellular and conventional dosimetry shows that D cel /D conv ratio ranges from 0.61 and O.89, in case of a cytoplasmic and a cell membrane distributions of radioactivity, depending on the radionuclide and cell dimensions. Thus, conventional dosimetry slightly overestimates the mean dose to the cell nucleus. On the other hand, D cel /D conv ranges from 1.1 to 75, in case of a cell nucleus distribution of radioactivity. Conventional dosimetry may strongly underestimates the absorbed dose to the nucleus, when radioactivity is located in the nucleus. The study indicates that in nuclear medicine imaging, cellular dosimetry may lead to a better understanding of biological effects of radiopharmaceuticals. (authors)

  8. Study of dosimetry CT in Skull for pediatric patients

    International Nuclear Information System (INIS)

    Ramos Amores, D.; Serna Berna, A.; Mata Colodro, F.; Puchades Puchades, V.

    2013-01-01

    The dose that receiving the patients in CT studies is the highest that can be received in a study of Radiology. If patients are children and we do studies with the same parameters as adults, they will receive a higher dose of radiation. This work seeks to expose the result of a dosimetric study on CT for children aged 0-15, carried out at the Hospital General Universitario de Santa Lucia in Cartagena during the year 2012. (Author)

  9. Personnel-dosimetry intercomparison studies at the Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Swaja, R.E.; Sims, C.S.

    1982-01-01

    Since 1974, seven annual personnel dosimetry intercomparison studies have been conducted at the Oak Ridge National Laboratory using the Health Physics Reactor. These studies have produced more than 2000 measurements by 72 participating organizations of neutron and gamma dose equivalents between 0.1 to 15.0 mSv in six mixed radiation fields. The relative performance of three basic types of personnel neutron dosimeters (nuclear emulsion film, thermoluminescent, and track-etch) and two basic types of gamma dosimeters (film and thermoluminescent) was assessed based on experimental results obtained during the seven intercomparisons

  10. Comparison of parameters affecting GNP-loaded choroidal melanoma dosimetry; Monte Carlo study

    Science.gov (United States)

    Sharabiani, Marjan; Asadi, Somayeh; Barghi, Amir Rahnamai; Vaezzadeh, Mehdi

    2018-04-01

    The current study reports the results of tumor dosimetry in the presence of gold nanoparticles (GNPs) with different sizes and concentrations. Due to limited number of works carried out on the brachytherapy of choroidal melanoma in combination with GNPs, this study was performed to determine the optimum size and concentration for GNPs which contributes the highest dose deposition in tumor region, using two phantom test cases namely water phantom and a full Monte Carlo model of human eye. Both water and human eye phantoms were simulated with MCNP5 code. Tumor dosimetry was performed for a typical point photon source with an energy of 0.38 MeV as a high energy source and 103Pd brachytherapy source with an average energy of 0.021 MeV as a low energy source in water phantom and eye phantom respectively. Such a dosimetry was done for different sizes and concentrations of GNPs. For all of the diameters, increase in concentration of GNPs resulted in an increase in dose deposited in the region of interest. In a certain concentration, GNPs with larger diameters contributed more dose to the tumor region, which was more pronounced using eye phantom. 100 nm was reported as the optimum size in order to achieve the highest energy deposition within the target. This work investigated the optimum parameters affecting macroscopic dose enhancement in GNP-aided brachytherapy of choroidal melanoma. The current work also had implications on using low energy photon sources in the presence of GNPs to acquire the highest dose enhancement. This study is conducted through four different sizes and concentrations of GNPs. Considering the sensitivity of human eye tissue, in order to report the precise optimum parameters affecting radiosensitivity, a comprehensive study on a wide range of sizes and concentrations are required.

  11. Quantitative autoradiography of radionuclides in biological tissues by high resolution nuclear analysis: application in radio-toxicology and dosimetry

    International Nuclear Information System (INIS)

    Aubineau Laniece, I.

    1997-01-01

    In the framework of radiation damage on cells in living organisms an auto-radiograph, based on the STIC method, has been developed for the particles detection. This apparatus associates a thin scintillator with a photosensitive detector (CCD). The design and the performance of this well adapted tool for low activity biological samples study, are described. (A.L.B.)

  12. Study on the establishment of retrospective dosimetry system for nuclear radiation accident(II)

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Shik; Chai, Ha Seok; Lee, Jong Ok [Chungnam National Univ., Taejon (Korea, Republic of)

    1999-03-15

    This study was driven forward centering around physical techniques in retrospective dosimetry system for encountering nuclear radiation accident. The results obtained through this study are summarized as follow : the minimal facilities based on physical techniques should be assured at KINS for appropriate operation and establishment of retrospective accident dosimetry system, the necessary apparatus and man power for retrospective dose assessment by physical techniques might be operated flexibly, however, CL and TL/OSL readers should be equipped with the highest priority, a series of comparative examination of several physical techniques for retrospective dose assessment revealed that most of the irradiated materials around accident sites are usable for the dose assessment, if a priori study on the dosimetrical characteristics of those materials is preceded in accordance with the species of the collectable samples, the results of the study on the CL-dose response and radiation energy dependence of sugar and sorbitol, showed the nonlinearity in CL-dose relationship at the range of low dose(less than 5 Gy), and it led us to perform a study on the correction of the nonlinearity, and in the later study, CL output showed heavy dependence on radiation energy in the energy below around 100 keV and accordingly, a study on the correction for the energy dependence was also carried out, ve were able to obtain good results as a first attempt to carry out such corrections.

  13. Studies on (Eu2+/Ce3+) activated fluoroperovskites for radiation dosimetry

    International Nuclear Information System (INIS)

    Joseph Daniel, D.; Ramasamya, P.; Madhusoodanan, U.; Annalakshmi, O.

    2014-01-01

    Thermoluminescence dosimetry is based on the principle that the amount of light released by the phosphor material, which has been previously exposed to ionizing radiation, will depend on the radiation dose received by the material. KMgF 3 and NaMgF 3 belongs to a family of fluoroperovskites, ABX 3 , (where A-alkali metal, B-alkali earth X-halide ions). In this paper, we present the results of TL induced by β - irradiation in co-doped ( Eu 2+ Ce 3+ ) fluoride single crystals. TL dose response and fading at room temperature have also been studied

  14. Study of the effects of radon in three biological systems

    International Nuclear Information System (INIS)

    Tavera, L.; Balcazar, M.; Lopez, A.; Brena, M.; Rosa, M.E. De la; Villalobos P, R.

    2002-01-01

    The radon and its decay products are responsible of the 3/4 parts of the exposure of the persons to the environmental radiation. The discovery at the end of XIX Century of the illnesses, mainly of cancer, which appeared in the presence of radon, lead to an accelerated growing of the radon studies: monitoring, dosimetry, effects on the persons, etc. Several epidemiological studies of radon in miners and population in general have been realized; advancing in the knowledge about the concentration-lung cancer risk relationship, but with discrepancies in the results depending on the concentration levels. Therefor, studies which consuming time, efforts and money go on doing. The research of the radon effects in biological systems different to human, allows to realize studies in less time, in controlled conditions and generally at lower cost, generating information about the alpha radiation effects in the cellular field. Therefor it was decided to study the response of three biological systems exposed to radon: an unicellular bacteria Escherichia Coli which was exposed directly to alpha particles from an electrodeposited source for determining the sensitivity limit of the chose technique. A plant, Tradescantia, for studying the cytogenetic effect of the system exposed to controlled concentrations of radon. An insect, Drosophila Melanogaster, for studying the genetic effects and the accumulated effects in several generations exposed to radon. In this work the experimental settlements are presented for the expositions of the systems and the biological results commenting the importance of these. (Author)

  15. Studies of aluminium nitride ceramics for application in UV dosimetry

    DEFF Research Database (Denmark)

    Trinkler, L.; Bøtter-Jensen, L.; Christensen, P.

    2000-01-01

    The study is reported of the ceramic material AlN-Y2O3 as a potential luminescence dosemeter for the detection of UV radiation. Both the thermoluminescence and the optically stimulated luminescence properties of the material have been studied after exposure to UV radiation and compared with those...... of the widely used dosemeter material Al2O3:C. It has been shown that AlN-Y2O3 ceramics exhibit three orders of magnitude higher sensitivity to UV radiation than does Al2O3,:C over a broad spectral region. The thermoluminescence from AlN-Y2O3 is characterised by linear dose dependence over a wide range....... The fading characteristics of the UV-induced thermoluminescence and optically stimulated luminescence signals with storage time at room temperature were found to be a drawback, but still lower than those induced after exposure to ionising radiation....

  16. Soil and terrestrial biology studies

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Soil and terrestrial biology studies focused on developing an understanding of the uptake of gaseous substances from the atmosphere by plants, biodegradation of oil, and the movement of Pu in the terrestrial ecosystems of the southeastern United States. Mathematical models were developed for SO 2 and tritium uptake from the atmosphere by plants; the uptake of tritium by soil microorganisms was measured; and the relationships among the Pu content of soil, plants, and animals of the Savannah River Plant area were studied. Preliminary results are reported for studies on the biodegradation of waste oil on soil surfaces

  17. Three-dimensional dosimetry in brachytherapy: A MAGAT study

    Energy Technology Data Exchange (ETDEWEB)

    Lin, M.-H. [Department of Family Medicine and Physical Check-up Center, Tainan Hospital Department of Health, Executive Yuan, Taiwan (China); Department of Nursing, National Tainan Institute of Nursing, Taiwan (China); Huang, T.-C. [Department of Biomedical Imaging and Radiological Science, China Medical University, Taiwan (China); Kao, M.-J. [Department of Family Medicine and Physical Check-up Center, Tainan Hospital Department of Health, Executive Yuan, Taiwan (China); Department of Nursing, National Tainan Institute of Nursing, Taiwan (China); Wu, Jay [Department of Radiological Technology, Central Taiwan University of Science and Technology, Taiwan (China); Chen, C.-L. [Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, No. 110, Sec. 1, Chien-Kuo N. Road, South District, Taichung 402, Taiwan (China); Wu, T.-H. [Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, No. 110, Sec. 1, Chien-Kuo N. Road, South District, Taichung 402, Taiwan (China)], E-mail: tung@csmu.edu.tw

    2009-07-15

    This study is to evaluate the influence of using different matrix size of smoothing filter for image post-processing and various slice thickness during MR imaging on dose estimation in Ir-192 HDR brachytherapy via normoxic polymer gel dosimeter. Our results show its sensitive nature in gel dosimeter while changing these parameters, among which the combination of 2 mm slice thickness of MR images and [5x5] smoothing filter are considered the optimal parameters to provide accurate dose estimations and isodose curves.

  18. Three-dimensional dosimetry in brachytherapy: A MAGAT study

    International Nuclear Information System (INIS)

    Lin, M.-H.; Huang, T.-C.; Kao, M.-J.; Wu, Jay; Chen, C.-L.; Wu, T.-H.

    2009-01-01

    This study is to evaluate the influence of using different matrix size of smoothing filter for image post-processing and various slice thickness during MR imaging on dose estimation in Ir-192 HDR brachytherapy via normoxic polymer gel dosimeter. Our results show its sensitive nature in gel dosimeter while changing these parameters, among which the combination of 2 mm slice thickness of MR images and [5x5] smoothing filter are considered the optimal parameters to provide accurate dose estimations and isodose curves.

  19. Use of thermoluminescent dosimetry in gamma radiation fields studies

    International Nuclear Information System (INIS)

    Carron, W.

    1987-01-01

    The depth-dose curves for gamma rays in material of interest to agronomy were obtained using lithium fluoride thermoluminescent dosimeters. The dose conversion factors for LiF were determined from curves of the absorved dose versus depth in water, wood and soil. Mathematics equations were chosen to best fit these curves. In the view of the results we came to the conclusion that in the studied materials the absorved radiation dose presents a great variation to the depth and could be correlated through of the exponential regression. (author)

  20. Outline of recent studies on dosimetry for external radiations

    International Nuclear Information System (INIS)

    Yamaguchi, Yasuhiro; Iwai, Satoshi.

    1995-01-01

    On the opportunity of adopting the new basic recommendation of ICRP in 1990, the research on the method of evaluating external radiation exposure dose has become to be carried out actively. In this recommendation, the definition of the dose used for radiation protection was changed largely, accordingly, the necessity to prepare the dose conversion factor based on the new definition and so on has arisen. Also in Japan, the research for this purpose has been carried out, and in January, 1995, the workshop on the recent method for evaluating external radiation exposure dose was held at Japan Atomic Energy Research Institute. In this report, the contents discussed at the workshop and the outline of the recent studies on this subject are described. As the international trend of dose evaluation, the recommendation of ICRP in 1990, the ICRU report 51 and the ICRP publication 71 by the joint ICRP/ICRU task group are introduced. In Japan, the studies have been advanced centering around the reassessment of dose conversion factors for photons, electrons and neutrons. The dose evaluation for photons, electrons and neutrons, and the dose evaluation around high energy accelerators are explained. Many problems to be solved still remain as the subjects of research for hereafter. (K.I.)

  1. Lactose and ''tris'' lyoluminescence dosimetry systems and ESR correlation studies

    International Nuclear Information System (INIS)

    Oommen, I.K.; Nambi, K.S.V.; Sengupta, S.; Rao, T.K.G.; Ravikumar, M.

    1989-01-01

    Lyoluminescence (LL) dosimeters have been developed using lactose monohydrate (disaccharide) and tris(hydroxymethyl)aminomethane (''Tris'') systems and attempts have been made to understand the LL mechanism through ESR correlation studies. Tris LL dosimeter has a γ-ray sensitivity with a linear response in the absorbed-dose range 0.05-200 Gy (5-2 x 10 4 rad), while the lactose response extends to a higher range from 1 to 10 4 Gy (10 2 -10 6 rad). The LL output of lactose and Tris did not show any appreciable decay for a period of 6 months after irradiation. ESR measurements show that free-radical concentration in both the systems increases with γ-ray dose in the range 10 2 -10 5 Gy. The minimum dose required to measure the radiation-induced ESR signal for Tris is ∼ 500 Gy, the dose at which the LL output saturates, while lactose shows a radiation-induced ESR signal right at the minimum dose where LL could be detected. The estimated spin density on the radical carbon atom is 0.7. ESR signal stabilities of lactose and Tris were also studied. Lactose did not show any appreciable ESR decay for a period of 3 months after irradiation, while, for Tris, one of the radicals showed a decay of 45% for the same period. (author)

  2. Occupational dose measurement in interventional cardiology, dosimetry comparison study

    International Nuclear Information System (INIS)

    Ahmad, A.M.A.

    2008-05-01

    The number of cardiology interventional procedures has significantly increased recently. This is due to the reliability of the diagnostic equipment to diagnose many heart disease. In the procedures the x-ray used results in increasing radiation doses to the staff. The cardiologists and other staff members in interventional cardiology are usually working close to the area under examination and receive the dose primarily from scattered radiation from the patient. Therefore workers in interventional cardiology are expected to receive high doses. This study overviews the status of occupational exposure at the three cardiology centers at three different hospitals in Khartoum compared with that received by workers at other medical practices (radiotherapy, nuclear medicine and diagnostic radiology) in the Institute of Nuclear and Technology (INMO) at El Gezira. The TLD Harshaw 6600 reader was used in the assessment of effective dose for Hp (10). Two TLDs were used by each worker at the three cardiology centres, one worn under a protective apron and the other worn outside and above the apron as specified by the ICRP. Each worker at the other sections was facilitated with one dosimeter to be worn on the chest. The annual doses received by 14 cardiologists, 13 nurses and 9 technologists at the three cardiology centres were in the range: (0.84-4.77), (0.15-2.08), (0.32-1.10) mSv respectively. In the INMO the annual doses received by 7 doctors, 5 nurses and 14 technologists were in the range: (0.12-0.51), (0.11-0.65), (0.03-1.39) mSv respectively. The results showed that the annual doses received by the workers do not exceed 20 mSv. The study also indicated that doses received by workers in interventional cardiology, in particular the cardiologists are high compared to that received at the other medical sections.(Author)

  3. A study on dosimetry for child in dentistry, 2

    International Nuclear Information System (INIS)

    Tateno, Hidemi; Itoh, Taizo; Higaki, Morio; Kanno, Masanori; Higashi, Tomomitsu

    1981-01-01

    Recently, we use X-ray inspection very frequently and take a X-ray picture by various technique in dental diagnosis. Patients in pedodontics usually do not appeal appropriately the symptom of their own disease because of their immaturness. For this reason, X-ray inspection plays a big part in diagnosis. Though the exposure dose became to social problem, it is demanded to play consideration to X-ray technique for children because of higher sensitivity than adult. But studies of the exposure dose are reported in medical field and few of them are about pedodontics. Therefore, distribution of exposure dose in the 6-film technique (intraoral technique) for children was surveyed by use of water phantom examining the reliability of TLD, the defect of scattered rays and indicator dependence etc. were tested in part. 1. But first report is two dimension, so we examined the 6-films technique, the body view of mandible, the orthopantomography and the cephalography for Mix-DP (for child). The following results were obtained. 1. The 6-film technique showed the highest exposure dose at skin, eye and thyroid gland. 2. The exposure dose at thyroid gland by 6-film technique was 0.734 R. 3. The exposure dose at gonad was less 0.001 R. by all technique. 4. The exposure dose at child tended to higher than adult by all technique. (author)

  4. Infants and young children modeling method for numerical dosimetry studies: application to plane wave exposure

    International Nuclear Information System (INIS)

    Dahdouh, S; Wiart, J; Bloch, I; Varsier, N; Nunez Ochoa, M A; Peyman, A

    2016-01-01

    Numerical dosimetry studies require the development of accurate numerical 3D models of the human body. This paper proposes a novel method for building 3D heterogeneous young children models combining results obtained from a semi-automatic multi-organ segmentation algorithm and an anatomy deformation method. The data consist of 3D magnetic resonance images, which are first segmented to obtain a set of initial tissues. A deformation procedure guided by the segmentation results is then developed in order to obtain five young children models ranging from the age of 5 to 37 months. By constraining the deformation of an older child model toward a younger one using segmentation results, we assure the anatomical realism of the models. Using the proposed framework, five models, containing thirteen tissues, are built. Three of these models are used in a prospective dosimetry study to analyze young child exposure to radiofrequency electromagnetic fields. The results lean to show the existence of a relationship between age and whole body exposure. The results also highlight the necessity to specifically study and develop measurements of child tissues dielectric properties. (paper)

  5. Infants and young children modeling method for numerical dosimetry studies: application to plane wave exposure

    Science.gov (United States)

    Dahdouh, S.; Varsier, N.; Nunez Ochoa, M. A.; Wiart, J.; Peyman, A.; Bloch, I.

    2016-02-01

    Numerical dosimetry studies require the development of accurate numerical 3D models of the human body. This paper proposes a novel method for building 3D heterogeneous young children models combining results obtained from a semi-automatic multi-organ segmentation algorithm and an anatomy deformation method. The data consist of 3D magnetic resonance images, which are first segmented to obtain a set of initial tissues. A deformation procedure guided by the segmentation results is then developed in order to obtain five young children models ranging from the age of 5 to 37 months. By constraining the deformation of an older child model toward a younger one using segmentation results, we assure the anatomical realism of the models. Using the proposed framework, five models, containing thirteen tissues, are built. Three of these models are used in a prospective dosimetry study to analyze young child exposure to radiofrequency electromagnetic fields. The results lean to show the existence of a relationship between age and whole body exposure. The results also highlight the necessity to specifically study and develop measurements of child tissues dielectric properties.

  6. Biological dosimetry after criticality accidents. Intercomparison exercise in the Silene Reactor - France; Dosimetria biologica en accidentes de criticidad. Ejercicio de intercomparacion en el Reactor Silene - Francia

    Energy Technology Data Exchange (ETDEWEB)

    Di Giorgio, Marina; Vallerga, Maria B; Taja, Maria R [Autoridad Regulatoria Nuclear, Buenos Aires (Argentina); arn gov ar, E-mail: mdigiorg@cae

    2004-07-01

    The Institute of Radiation Protection and Nuclear Safety Institute (IRSN) organized an international biological dosimetry intercomparison, at the SILENE experimental reactor (Valduc, France), simulating different criticality scenarios: bare source 4 Gy, lead shield source 1 and 2 Gy and gamma pure {sup 60}Co source 2 Gy. Fifteen laboratories were involved in this exercise, including the Argentine Biological Dosimetry Laboratory. The purposes of the intercomparison were: 1) To compare the unstable chromosome aberration (UCA) frequency observed by the different laboratories; and 2) To compare the dose estimation for gamma rays and neutrons. The objects of the present work were: I) To compare the mean frequency of UCA observed by the Argentine laboratory with the mean frequency observed by the participant laboratories as a whole. II) To compare the dose estimates performed by the Argentine lab with those estimated by the other laboratories involved in the second stage of the intercomparison. Overall, the mean frequencies of UCA and the correspondent 95% confidence limits obtained by the Argentine lab were consistent with the results obtained by the laboratories as a whole. For the gamma pure scenario, smaller variations were observed among laboratories in terms of dose (CV=18,2%) than in terms of frequency (CV=30,1%). For the mixed field scenarios, only four laboratories, including the Argentine lab, estimated gamma and neutron components of the total dose and just two (Argentine lab and lab 12) were in agreement with the given physical doses. The 1 Gy experiment presented lesser variations both in terms of frequency and dose than the other two scenarios. For the 4 and 2 Gy experiments, variations in neutron dose were more significant than variations in gamma dose, related to the magnitude of the dose. The results suggest that intercomparison exercises jointly with the accreditation of biological dosimetry by cytogenetic service laboratories, in compliance with ISO

  7. ESR Dosimetry

    International Nuclear Information System (INIS)

    Baffa, Oswaldo; Rossi, Bruno; Graeff, Carlos; Kinoshita, Angela; Chen Abrego, Felipe; Santos, Adevailton Bernardo dos

    2004-01-01

    ESR dosimetry is widely used for several applications such as dose assessment in accidents, medical applications and sterilization of food and other materials. In this work the dosimetric properties of natural and synthetic Hydroxyapatite, Alanine, and 2-Methylalanine are presented. Recent results on the use of a K-Band (24 GHz) ESR spectrometer in dosimetry are also presented

  8. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 7 2155 http://cern.ch/rp-dosimetry

  9. Dosimetry Service

    CERN Multimedia

    Dosimetry Service

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service Tel. 7 2155 http://cern.ch/rp-dosimetry

  10. Dosimetry Service

    CERN Multimedia

    2005-01-01

    Please remember to read your dosimeter at least once a month. Regular read-outs are vital to ensure that your personal dose is periodically monitored. Dosimeters should be read even if you have not visited the controlled areas. Dosimetry Service - Tel. 72155 http://cern.ch/rp-dosimetry

  11. Biological dosimetry of patients with differenced carcinoma of thyroid treated with Iodine-131; Dosimetria biologica de pacientes con carcinoma diferenciado de tiroides tratados con Iodo-131

    Energy Technology Data Exchange (ETDEWEB)

    Vallerga, M. B.; Rojo, A.M.; Taja, M.R.; Deluca, G.; Di Giorgio, M. [Autoridad Regulatoria Nuclear Av. Del Libertador 8250 (C1429BNP). Buenos Aires (Argentina); Fadel, A. [Hospital General de Agudos Dr. Carlos Durand Av. Diaz Velez 5044. Buenos Aires (Argentina); Cabrejas, M.; Valdivieso, C. [Hospital de Clfnicas Jose de San Martin Av. Cordoba 2351 (CP1120). Buenos Aires (Argentina)]. e-mail: mvallerg@cae.arn.gov.ar

    2006-07-01

    The administration of I-131 to patient with Differentiated Thyroid Carcinoma (CaDiT) it is used inside the therapeutic outline as later step to the thyroidectomy. However, the good activity to give is of difficult determination due to factors such as, the variability in the capacity of tumoral reception of the I-131, distribution of the pharmaceutical, physiologic status, other associate pathologies, grade of advance of the illness, and previous treatments. Additionally, the activity to administer is dependent of the dose of tolerance in the healthy tissues; superior dose to 2 Gy in bone marrow, its could drive to myelotoxicity. At the moment, the form more extended of administration it is the empiric prescription that considers clinical parameters and of laboratory for their determination. Presently work, the protocol of applied treatment incorporates the evaluation for internal dosimetry and biological dosimetry to estimate absorbed dose in bone marrow. The biological estimate of the dose of these patients is based on the quantification of chromosomal aberrations whose frequency is referred to a curve-dose response in which the lymphocytes is irradiated in vitro with I-131, allowing to determine the in vivo dose to the patient's circulating lymphocytes. The objective of the present work is to determine the applicability of different cytogenetic essays in the estimate of the absorbed dose to the whole body or specific organs. Three patients were evaluated with CaDiT. Their treatment protocol consisted on a tracer administration of radioactive iodine of 74 - 111 MBq (2 - 3 mCi) and a therapy 7,4 - 11,1 GBq (200 - 300 mCi). Previous to the tracer administration and 8 days post-therapeutic administration took samples of veined blood that were evaluated by biological dosimetry by means of the application of the techniques: conventional cytogenetic Micronucleus and FISH (Hybridization in situ by Fluorescence). Starting from the frequencies of observed chromosomal

  12. Nineteenth nuclear accident dosimetry intercomparison study, August 9-13, 1982

    International Nuclear Information System (INIS)

    Greene, R.T.; Sims, C.C.; Swaja, R.E.

    1983-11-01

    The Nineteenth Nuclear Accident Dosimetry Intercomparison Study was held August 9 to 13, 1982, at the Oak Ridge National Laboratory using the Health Physics Research Reactor operated in the pulse mode to simulate nuclear criticality accidents. Participants from eight organizations measured neutron and gamma doses at air stations and on phantoms for three different shielding conditions. Measured results were compared to nuclear industry guidelines for criticality accident dosimeters which suggest accuracies of +-25% for neutron dose and +-20% for gamma dose. Seventy-two percent of the neutron dose measurements using foil activation, sodium activation, hair sulfur activation, and thermoluminescent methods met the guidelines while less than 40% of the gamma dose measurements were within +-20% of reference values. The softest neutron energy spectrum (also lowest neutron/gamma dose ratio) provided the most difficulty in measuring neutron and gamma doses. Results of this study indicate the need for continued intercomparison and testing of nuclear accident dosimetry systems and for training of evaluating personnel. 14 references, 7 figures, 16 tables

  13. Dosimetry study comparing NCS report-2 versus IAEA TRS-398 protocol for high energy photon beams

    International Nuclear Information System (INIS)

    Attalaa, E.M.; Khaled, N.E.; Abou Elenein, H.S.; Elsayed, A.A.

    2005-01-01

    In this work a dosimetry study is presented in which the results of absorbed dose determined at reference condition according to the IAEA TRS-398 protocol and the NCS report-2 are compared. The IAEA TRS-398 protocol for absorbed dose calibration is based on ionization chamber having absorbed dose to water calibration factor N d w, while the NCS-2 dosimetry report for absorbed dose calibration is based on an ionization chamber having air- kerma calibration factor N k . This study shows that the absorbed dose which is calculated with The IAEA TRS-398 formalisms is higher than that calculated with NCS report-2 formalisms within range from 0.4 to 0.9% in cobalt-60 beam as sensed by different ionization chambers, and from 0.2 to 1.1% for different higher energy photon beams of 6, 8 and 18 MV. The chambers used are PTW 30001, 30004, and NE-2571; which have calibration factors N k and N d w traceable to the BIPM (Bureau International des Poids et Mesures)

  14. Study of carbon-doped micro and nano sized alumina for radiation dosimetry applications

    International Nuclear Information System (INIS)

    Fontainha, C. C. P.; Alves, N.; Ferraz, W. B.; Faria, L. O.

    2017-10-01

    New materials have been widely investigated for ionizing radiation dosimetry for medical procedures. Carbon-doped doped alumina (Al 2 O 3 :C) have been proposed as thermoluminescent and photo luminescent dosimeters. In the present study nano and micro-sized alumina doped with different percentages of carbon, sintered under different atmosphere conditions, at temperatures ranging from 1300 to 1750 degrees Celsius, were sintered and their dosimetric characteristics for gamma fields were investigated. Among the investigated sample preparation methods, the micro-sized alumina doped with 0.01% of carbon and sintered at 1700 degrees Celsius under reducing atmosphere has presented the best Tl output, comparable to the best Tl sensitivities ever reported to alumina and better efficiency than the nano-sized alumina synthesized in this study. The influence of humidity in the Tl signal has been evaluated to be -4.0%. The micro-sized alumina obtained by the methodology used in this work is a suitable candidate for application in X and gamma radiation dosimetry. (Author)

  15. Dating by fission track method: study of neutron dosimetry with natural uranium thin films

    International Nuclear Information System (INIS)

    Iunes, P.J.

    1990-06-01

    Fission track dating is described, focalizing the problem of the decay constant for spontaneous fission of 238 U and the use of neutron dosimetry in fission track analysis. Experimental procedures using thin films of natural uranium as neutron dosimeters and its results are presented. The author shows a intercomparison between different thin films and between the dosimetry with thin film and other dosimetries. (M.V.M.). 52 refs, 12 figs, 9 tabs

  16. Receptor studies in biological psychiatry

    International Nuclear Information System (INIS)

    Fujiwara, Yutaka

    1992-01-01

    Recent advances in the pharmacological treatment of endogenous psychosis have led to the development of biological studies in psychiatry. Studies on neurotransmitter receptors were reviewed in order to apply positron-emission tomograph (PET) for biological psychiatry. The dopamine (DA) hypothesis for schizophrenia was advanced on the basis of the observed effects of neuroleptics and methamphetamine, and DA(D 2 ) receptor supersensitivity measured by PET and receptor binding in the schizophrenic brain. The clinical potencies of neuroleptics for schizophrenia were correlated with their abilities to inhibit the D 2 receptor, and not other receptors. The σ receptor was expected to be a site of antipsychotic action. However, the potency of drugs action on it was not correlated with clinical efficacy. Haloperidol binds with high affinity to the σ receptor, which may mediate acute dystonia, an extrapyramidal side effect of neuroleptics. Behavioral and neurochemical changes induced by methamphetamine treatment were studied as an animal model of schizophrenia, and both a decrease of D 2 receptor density and an increase of DA release were detected. The monoamine hypothesis for manic-depressive psychosis was advanced on the basis of the effect of reserpine, monoamine oxidase inhibitor and antidepressants. 3 H-clonidine binding sites were increased in platelet membranes of depressive patients, 3 H-imipramine binding sites were decreased. The GABA A receptor is the target site for the action of anxiolytics and antiepileptics such as benzodiazepines and barbiturates. Recent developments in molecular biology techniques have revealed the structure of receptor proteins, which are classified into two receptor families, the G-protein coupled type (D 2 ) and the ion-channel type (GABA A ). (J.P.N.)

  17. High-accuracy dosimetry study for intensity-modulated radiation therapy(IMRT) commissioning

    International Nuclear Information System (INIS)

    Jeong, Hae Sun

    2010-02-01

    Intensity-modulated radiation therapy (IMRT), an advanced modality of high-precision radiotherapy, allows for an increase in dose to the tumor volume without increasing the dose to nearby critical organs. In order to successfully achieve the treatment, intensive dosimetry with accurate dose verification is necessary. A dosimetry for IMRT, however, is a challenging task due to dosimetric ally unfavorable phenomena such as dramatic changes of the dose at the field boundaries, dis-equilibrium of the electrons, non-uniformity between the detector and the phantom materials, and distortion of scanner-read doses. In the present study, therefore, the LEGO-type multi-purpose dosimetry phantom was developed and used for the studies on dose measurements and correction. Phantom materials for muscle, fat, bone, and lung tissue were selected after considering mass density, atomic composition, effective atomic number, and photon interaction coefficients. The phantom also includes dosimeter holders for several different types of detectors including films, which accommodates a construction of different designs of phantoms as necessary. In order to evaluate its performance, the developed phantom was tested by measuring the point dose and the percent depth dose (PDD) for small size fields under several heterogeneous conditions. However, the measurements with the two types of dosimeter did not agree well for the field sizes less than 1 x 1 cm 2 in muscle and bone, and less than 3 x 3 cm 2 in air cavity. Thus, it was recognized that several studies on small fields dosimetry and correction methods for the calculation with a PMCEPT code are needed. The under-estimated values from the ion chamber were corrected with a convolution method employed to eliminate the volume effect of the chamber. As a result, the discrepancies between the EBT film and the ion chamber measurements were significantly decreased, from 14% to 1% (1 x 1 cm 2 ), 10% to 1% (0.7 x 0.7 cm 2 ), and 42% to 7% (0.5 x 0

  18. High-accuracy dosimetry study for intensity-modulated radiation therapy(IMRT) commissioning

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Hae Sun

    2010-02-15

    Intensity-modulated radiation therapy (IMRT), an advanced modality of high-precision radiotherapy, allows for an increase in dose to the tumor volume without increasing the dose to nearby critical organs. In order to successfully achieve the treatment, intensive dosimetry with accurate dose verification is necessary. A dosimetry for IMRT, however, is a challenging task due to dosimetric ally unfavorable phenomena such as dramatic changes of the dose at the field boundaries, dis-equilibrium of the electrons, non-uniformity between the detector and the phantom materials, and distortion of scanner-read doses. In the present study, therefore, the LEGO-type multi-purpose dosimetry phantom was developed and used for the studies on dose measurements and correction. Phantom materials for muscle, fat, bone, and lung tissue were selected after considering mass density, atomic composition, effective atomic number, and photon interaction coefficients. The phantom also includes dosimeter holders for several different types of detectors including films, which accommodates a construction of different designs of phantoms as necessary. In order to evaluate its performance, the developed phantom was tested by measuring the point dose and the percent depth dose (PDD) for small size fields under several heterogeneous conditions. However, the measurements with the two types of dosimeter did not agree well for the field sizes less than 1 x 1 cm{sup 2} in muscle and bone, and less than 3 x 3 cm{sup 2} in air cavity. Thus, it was recognized that several studies on small fields dosimetry and correction methods for the calculation with a PMCEPT code are needed. The under-estimated values from the ion chamber were corrected with a convolution method employed to eliminate the volume effect of the chamber. As a result, the discrepancies between the EBT film and the ion chamber measurements were significantly decreased, from 14% to 1% (1 x 1 cm{sup 2}), 10% to 1% (0.7 x 0.7 cm{sup 2}), and 42

  19. Design, characterization and use of replicate human upper airways for radon dosimetry studies

    International Nuclear Information System (INIS)

    Swift, D.L.; Cheng, Y.S.; Su, Y.F.; Yeh, H.C.

    1992-01-01

    The size distribution of inhaled radon progeny aerosols is a significant factor in dosimetry. The role of the airways above the trachea is an important determinant of the respiratory distribution of both attached and unattached progeny aerosols. In order to provide information on the effect of particle size and breathing conditions on the overall and local deposition, we have developed a method to produce a replicate airway model from an in vivo magnetic resonance imaging coronal scan. The model consists of a sandwich of methacrylate elements, each element having the thickness of the scan interval. The transition between successive scan outlines traced on the front and back surfaces of each element is handsculpted in the plastic. The hollow model of the nasal passages thus produced has been characterized both morphologically and fluid-mechanically and has a flow resistance typical of a normal adult. The model has several distinct advantages for studies of radon progeny aerosol deposition. After exposure to a radioaerosol (or to an aerosol of an otherwise measurable substance) the individual elements can be separated to determine local deposition. The dimensions of specific upper-airway regions can be changed by replacing a small number of elements. The model has been incorporated in an exposure system for determining overall nandregional deposition of aerosols whose median diameter is approximately 1.7 nm. Measurements at several flow rates are presented to demonstrate use of the model in radon dosimetry. The model should also be useful for determining the airway deposition of other environmental aerosols

  20. Radiotherapy Based On α Emitting Radionuclides: Geant4 For Dosimetry And Micro-/Nano-Dosimetry

    International Nuclear Information System (INIS)

    Guatelli, Susanna

    2013-01-01

    Possible physics approaches to evaluate the efficacy of TAT are dosimetry, microdosimetry and nanodosimetry. Dosimetry is adequate when mean absorbed dose to a macroscopic target volume is important to understand the biological effect of radiation. General purpose Monte Carlo (MC) codes, based on condensed history approach, are a very useful, cost effective tool to solve dosimetric problems. The condensed history approach is based on the use of multiple scattering theories to calculate the energy losses and angular changes in the direction of the particle. The short α particle range and high LET make the microdosimetric approach more suitable than dosimetry to study TAT from first physics principles, as this approach takes into account the stochastic nature of energy deposition at cellular level

  1. Validation of an immunochemical assay for the detection of DNA damage as a tool for biological dosimetry of human exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Schans, G.P. van der; Timmerman, A.J.; Wojewodzka, M.; Zaim, J.

    1997-01-01

    A method for biological dosimetry based on the immunochemical detection of DNA damage in human white blood cells has been validated. To this end the method developed at TNO (Rijswijk, the Netherlands) was also set up at INCT (Warsaw, Poland). Blood samples of 11 individuals were irradiated with 0 or 5 Gy of 170 kV X-rays at INCT and analyzed both at INCT and TNO. It appeared that in both laboratories damage could be detected to the same extent. The average background level of DNA damage amounted to 1.0 Gy-eq with an interindividual standard deviation of 0.25 Gy. The contribution of the sample variance to the total variance is only 14%. The radiosensitivity showed only a variation of about 10% and can, therefore, be neglected in estimating the radiation dose from the amount of DNA damage detected. (author)

  2. Foundations of ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Denisenko, O.N.; Pereslegin, I.A.

    1985-01-01

    Foundations of dosimetry in application to radiotherapy are presented. General characteristics of ionizing radiations and main characteristics of ionizing radiation sources, mostly used in radiotherapy, are given. Values and units for measuring ionizing radiation (activity of a radioactive substance, absorbed dose, exposure dose, integral dose and dose equivalent are considered. Different methods and instruments for ionizing radiation dosimetry are discussed. The attention is paid to the foundations of clinical dosimetry (representation of anatomo-topographic information, choice of radiation conditions, realization of radiation methods, corrections for a configuration and inhomogeneity of a patient's body, account of biological factors of radiation effects, instruments of dose field formation, control of irradiation procedure chosen)

  3. Using exposure prediction tools to link exposure and dosimetry for risk based decisions: a case study with phthalates

    Science.gov (United States)

    The Population Life-course Exposure to Health Effects Modeling (PLETHEM) platform being developed provides a tool that links results from emerging toxicity testing tools to exposure estimates for humans as defined by the USEPA. A reverse dosimetry case study using phthalates was ...

  4. Results of a dosimetry study in the European Community on frequent X ray examinations in infants

    International Nuclear Information System (INIS)

    Schneider, K.; Fendel, H.; Bakowski, C.

    1992-01-01

    This Europe-wide dosimetry study, covering 89 departments in 11 EC countries, measured entrance surface dose (ESD) using TLDs, and surveyed X ray equipment and radiographic techniques used for frequent paediatric X ray examinations of the chest, abdomen, pelvis, skull and spine. The survey was limited to infants (10 months, 4 months and prematures of ∼ 1 kg). Data analysis showed widely differing radiographic techniques. This was one of the reasons for the large variations in ESD of an order of magnitude of 1:50. A substantial number of departments used either very old X ray generators and/or techniques poorly suited for paediatric radiology. Significant dose reduction was seen when recommended guidelines for good radiographic technique were followed. This study emphasises the necessity for the adherence to easily followed guidelines for the improvement of training and equipment in paediatric radiology. (author)

  5. Results of a dosimetry study in the European Community on frequent X ray examinations in infants

    International Nuclear Information System (INIS)

    Schneider, K.; Fendel, H.; Bakowski, C.; Stein, E.; Kohn, M.; Kellner, M.; Schweighofer, K.; Cartagena, G.; Panzer, W.; Scheurer, C.; Wall, B.

    1992-01-01

    This Europe-wide dosimetry study, covering 89 departments in 11 EC countries, measured entrance surface dose (ESD) using TLDs, and surveyed X ray equipment and radiographic techniques used for frequent paediatric X ray examinations of the chest, abdomen, pelvis, skull and spine. The survey was limited to infants (10 months, 4 months and prematures of ∼ 1 kg). Data analysis shows that radiographic techniques differed widely. This was one of the reasons for the large variations in ESD of an order of magnitude of 1:50. A substantial number of departments used either very old X ray generators and/or techniques which are poorly suited for paediatric radiology. A significant dose reduction was seen when recommended guidelines for good radiographic technique were followed. The results of this study emphasize the necessity for the adherence to easily followed guidelines for the improvement of training and equipment in paediatric radiology

  6. Dosimetry in radionuclide therapy

    International Nuclear Information System (INIS)

    Riccabona, G.

    2001-01-01

    While it is known that therapeutic effects of radionuclides are due to absorbed radiation dose and to radiosensitivity, individual dosimetry in 'Gy' is practiced rarely in clinical Nuclear Medicine but 'doses' are described in 'mCi' or 'MBq', which is only indirectly related to 'Gy' in the target. To estimate 'Gy', the volume of the target, maximum concentration of the radiopharmaceutical in it and residence time should be assessed individually. These parameters can be obtained usually only with difficulty, involving possibly also quantitative SPET or PET, modern imaging techniques (sonography, CT, MRT), substitution of y- or positron emitting radiotracers for β - emitting radiopharmaceuticals as well as whole-body distribution studies. Residence time can be estimated by obtaining data on biological half-life of a comparable tracer and transfer of these data in the physical characteristics of the therapeutic agent. With all these possibilities for gross dosimetry the establishment of a dose-response-relation should be possible. As distribution of the radiopharmaceutical in lesions is frequently inhomogenous and microdosimetric conditions are difficult to assess in vivo as yet, it could be observed since decades that empirically set, sometimes 'fixed' doses (mCi or MBq) can also be successful in many diseases. Detailed dosimetric studies, however, are work- and cost-intensive. Nevertheless, one should be aware at a time when more sophisticated therapeutic possibilities in Nuclear Medicine arise, that we should try to estimate radiation dose (Gy) in our new methods even as differences in individual radiosensitivity cannot be assessed yet and studies to define individual radiosensitivity in lesions should be encouraged. (author)

  7. Dosimetry methods

    DEFF Research Database (Denmark)

    McLaughlin, W.L.; Miller, A.; Kovacs, A.

    2003-01-01

    Chemical and physical radiation dosimetry methods, used for the measurement of absorbed dose mainly during the practical use of ionizing radiation, are discussed with respect to their characteristics and fields of application....

  8. Eleventh ORNL personnel dosimetry intercomparison study, May 22-23, 1985

    International Nuclear Information System (INIS)

    Swaja, R.E.; Oyan, R.; Sims, C.S.

    1986-07-01

    The Eleventh Personnel Dosimetry Intercomparison Study was conducted at the Oak Ridge National Laboratory (ORNL) during May 22-23, 1985. Dosimeter badges from 44 participating organizations were mounted on Lucite block phantoms and exposed to four mixed-radiation fields with neutron dose equivalents around 5 mSv and gamma dose equivalents between 0.1 and 0.7 mSv. Results of this study indicated that no participants had difficulty obtaining measurable indication of neutron exposure at the provided dose equivalent levels, and very few had difficulty obtaining indication of gamma exposure at dose equivalents as low as 0.10 mSv. Average neutron results for all dosimeter types were within 20% of reference values with no obvious spectrum dependence. Different dosimeter types (albedo, direct interaction TLD, film, recoil track, and combination albedo-track) with 10 or more reported measurements provided average results within 35% of reference values for all spectra. With regard to precision, about 80% of the reported neutron results had single standard deviations within 10% at the means which indicates that precision is not a problem relative to accuracy for most participants. Average gamma results were greater than reference values by factors of 1.07 to 1.52 for the four exposures with TLD systems being more accurate than film. About 80% of all neutron results and 67% of all gamma results met regulatory standards for measurement accuracy and approximately 70% of all neutron data satisfied national dosimetry accreditation criteria for accuracy plus precision. In general, neutron dosimeter performance observed in this intercomparison was much improved compared to that observed in the prior studies while gamma dosimeter performance was about the same

  9. Comparison of two methods of quantitation in human studies of biodistribution and radiation dosimetry

    International Nuclear Information System (INIS)

    Smith, T.

    1992-01-01

    A simple method of quantitating organ radioactivity content for dosimetry purposes based on relationships between organ count rate and the initial whole body count rate, has been compared with a more rigorous method of absolute quantitation using a transmission scanning technique. Comparisons were on the basis of organ uptake (% administered activity) and resultant organ radiation doses (mGy MBq -1 ) in 6 normal male volunteers given a 99 Tc m -labelled myocardial perfusion imaging agent intravenously at rest and following exercise. In these studies, estimates of individual organ uptakes by the simple method were in error by between +24 and -16% compared with the more accurate method. However, errors on organ dose values were somewhat less and the effective dose was correct to within 3%. (Author)

  10. Luminescence characteristics of dental ceramics for retrospective dosimetry: a preliminary study

    International Nuclear Information System (INIS)

    Bailiff, I.K.; Correcher, V.; Delgado, A.; Goksu, Y.; Huebner, S.

    2002-01-01

    Ceramic materials that are widely employed in dental prosthetics and repairs exhibit luminescent properties. Because of their use in the body, these materials are potentially of interest in situations where retrospective dosimetry for individuals is required but where monitoring was not planned. The luminescent properties of dental ceramics obtained in Germany, Spain and the UK were examined. Linear dose-response characteristics were obtained in the range <100 mGy to 10 Gy using thermoluminescence (TL), optically stimulated luminescence and infrared-stimulated luminescence measurement techniques. Measurements of time-resolved luminescence were also performed to examine the nature of the luminescence recombination under visible (470 nm) and IR (855 nm) stimulation. The results obtained by TL and optically stimulated techniques suggest that there may be deeper traps than previously observed in certain types of dental ceramic. Such traps may be less susceptible to optical and athermal fading than was reported in earlier studies. (author)

  11. Utero-fetal unit and pregnant woman modeling using a computer graphics approach for dosimetry studies.

    Science.gov (United States)

    Anquez, Jérémie; Boubekeur, Tamy; Bibin, Lazar; Angelini, Elsa; Bloch, Isabelle

    2009-01-01

    Potential sanitary effects related to electromagnetic fields exposure raise public concerns, especially for fetuses during pregnancy. Human fetus exposure can only be assessed through simulated dosimetry studies, performed on anthropomorphic models of pregnant women. In this paper, we propose a new methodology to generate a set of detailed utero-fetal unit (UFU) 3D models during the first and third trimesters of pregnancy, based on segmented 3D ultrasound and MRI data. UFU models are built using recent geometry processing methods derived from mesh-based computer graphics techniques and embedded in a synthetic woman body. Nine pregnant woman models have been generated using this approach and validated by obstetricians, for anatomical accuracy and representativeness.

  12. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with the design and measurement of physical parameters used in theory or to support biological experiments. The radiation biophysics program tests and uses the theoretical developments for experimental design, and provides information for further theoretical development through experiments on cellular systems

  13. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with design and measurement of those physical parameters used in the theory or to support biological experiments. The radiation biophysics program tests and makes use of the theoretical developments for experimental design. Also, this program provides information for further theoretical development through experiments on cellular systems

  14. Radiation cytogenetic in vitro studies on human donors in the development of a suitable biological dosimeter

    International Nuclear Information System (INIS)

    Barjaktarovic, N.

    1988-02-01

    The final report is on the work carried out under the Agency research contract 3173/RB entitled ''Radiation cytogenetic in vitro studies on human donors in the development of a suitable biological dosimeter'', at the Clinical Hospital Centre ''Zvezdara'' in Belgrade, Yugoslavia. In co-operation and co-ordination dissemination with an international team of cytogeneticists under the IAEA CRP, the development of a suitable biological dosimetry system has been accomplished at the national institute to assist reliably in the absorbed radiation-dose assessment of accidentally-over-exposed personnel. The quantitative yield of asymmetrical chromosomal aberrations, such as dicentrics, rings and fragments consequent to exposure(s) to radiation overdose, help in such estimation of vital prognostic and radiation protection significance. This biological dosimeter system is particularly essential where the exposed person was not wearing any physical dosemeter during the accident. Prerequisite for implementation of an effective biological dosimetry is the availability of a reliable standard dose-response curve and an adherence to a protocol for lymphocytic chromosome analysis in first division phase of lymphocytes. The validation of the reported biological dosimeter is established through its successful analysis of a simulated over-exposure incident, with the associated error of less than 10%. Analytical cytogenetic methods for whole- and part-body acute exposures have been discussed. Part of the results have been reported in the publications under the CRP concerned

  15. Activities developed by the biological dosimetry laboratory of the Autoridad Regulatoria Nuclear - ARN of Argentina; Actividades desarrolladas por el laboratorio de dosimetria biologica de la Autoridad Regulatoria Nuclear de Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Radl, A.; Sapienza, C. E.; Taja, M. R.; Bubniak, R.; Deminge, M.; Di Giorgio, M., E-mail: csapienza@arn.gob.ar [Autoridad Regulatoria Nuclear (ARN), Buenos Aires (Argentina)

    2013-07-01

    Biological dosimetry (DB) allows to estimate doses absorbed in individuals exposed to ionizing radiation through the quantification of stable and unstable chromosome aberrations (SCA and UCA). The frequency of these aberrations is referred to a calibration dose response curve (in vitro) to determine the doses of the individual to the whole body. The DB is a necessary support for programs of national radiation protection and response systems in nuclear or radiological emergencies in the event of accidental or incidental, single overexposure or large scale. In this context the Laboratory of Dosimetry Biological (LDB) of the Authority Regulatory Nuclear (ARN) Argentina develops and applies different dosimeters cytogenetic from four decades ago. These dosimeters provide a fact more within the whole of the information necessary for an accidental, complementing the physical and clinical dosimetry exposure assessment. The most widely used in the DB biodosimetric method is the quantification of SCA (dicentrics and rings Central) from a sample of venous blood. The LDB is accredited for the trial, under rules IRAM 301: 2005 (ISO / IEC 17025: 2005) and ISO 19238:2004. Test applies to the immediate dosimetry evaluation of acute exposures, all or a large part of the body in the range 0,1-5 Gy. In this context the LDB is part of the Latin American network of DB (LBDNet), BioDoseNet-who and response system in radiological emergencies and nuclear IAEA-RANET, being enabled to summon the LBDNet if necessary.

  16. Dosimetry studies with TLDs for stereotactic radiation techniques for intraocular tumours

    International Nuclear Information System (INIS)

    Ertl, A.; Schoeggl, A.; Zehetmayer, M.; Kindl, P.; Hartl, R.

    1997-01-01

    Between March 1993 and January 1997, stereotactic radiation techniques were used to irradiate 66 intraocular tumour patients with the Gamma Knife (Leksell Gamma Knife, model B unit) at the University of Vienna, Austria. This study investigates the dosimetry for stereotactic irradiation of ocular structures. For the dosimetry program KULA 4.4, Gamma Knife stereotactic irradiation of the eye represents an extreme frontal skull position. In addition, irradiation of the eye may be performed in the usual supine position in exceptional cases only. With the patient in the prone position, the dose planning program has to calculate with a significantly large number of single-beam extrapolations. In our first experiment we measured the isocentre dose for eight different γ-angle positions, both in prone and supine positions, using TLD measurements in an Alderson head phantom. We found a maximum deviation of ±1.6% using these individually calibrated TLDs. In the second experiment we examined the dose cross profiles for the two most frequently used treatment positions (supine position, γ = 65 deg., and prone position, γ = 140 deg.). For this purpose we implanted a specially designed TLD array into the orbit of a human cadaver head. We found excellent agreement of the dose values measured for the isocentre as well as the posterior part of the eye with orbit with deviations of less than -2.7%. However, for the anterior part of the eye, deviations between computer-generated calculations and the TLD measurements were found to range up to -30%. These differences were noticed both for supine and prone positions. For the Gamma Knife stereotactic irradiation of ocular tumours or pathologies, precautions should be taken to avoid significant underdosage in the anterior part of the radiation field. (author)

  17. ISDD: A computational model of particle sedimentation, diffusion and target cell dosimetry for in vitro toxicity studies

    Science.gov (United States)

    2010-01-01

    doses on a particle surface area or number basis can be as high as three to six orders of magnitude. As a consequence, in vitro hazard assessments utilizing mass-based exposure metrics have inherently high errors where particle number or surface areas target cells doses are believed to drive response. The gold standard for particle dosimetry for in vitro nanotoxicology studies should be direct experimental measurement of the cellular content of the studied particle. However, where such measurements are impractical, unfeasible, and before such measurements become common, particle dosimetry models such as ISDD provide a valuable, immediately useful alternative, and eventually, an adjunct to such measurements. PMID:21118529

  18. ISDD: A computational model of particle sedimentation, diffusion and target cell dosimetry for in vitro toxicity studies

    Directory of Open Access Journals (Sweden)

    Chrisler William B

    2010-11-01

    g/mL basis and target cell doses on a particle surface area or number basis can be as high as three to six orders of magnitude. As a consequence, in vitro hazard assessments utilizing mass-based exposure metrics have inherently high errors where particle number or surface areas target cells doses are believed to drive response. The gold standard for particle dosimetry for in vitro nanotoxicology studies should be direct experimental measurement of the cellular content of the studied particle. However, where such measurements are impractical, unfeasible, and before such measurements become common, particle dosimetry models such as ISDD provide a valuable, immediately useful alternative, and eventually, an adjunct to such measurements.

  19. Establishment of the Dosicard operational dosimetry system in a nuclear studies center

    International Nuclear Information System (INIS)

    Banchetry, C.

    2001-01-01

    Since the decree of March 1999, each employer of the French nuclear industry must set an operational dosimetry in its company. The method is based on electronic dosimeters equipped with alarms and worn by all the employees. The dosimeters are linked to a computer network. The operational dosimetry is recommended, to optimize the protection of workers and limit the doses received, to respect the principle of equity between the workers, to preserve a ''margin of dose'' in case of any unexpected event. The CEA executives have decided to use the EURISYS MESURES DOSICARD as an operational and complementary dosimetry tool. (author)

  20. The sensitivity analysis of tooth enamel to the absorbed dose for the application to EPR dosimetry

    International Nuclear Information System (INIS)

    Hong, Dae Seok; Lee, Kun Jai; Cho, Young Hwan

    2002-01-01

    Electron Paramagnetic Resonance (EPR) spectroscopy is one of the methods applicable to retrospective dosimetry. The retrospective dosimetry is a process that is a part of dose reconstruction for estimation of exposed dose occurred years before the estimation. Many techniques can be used to the retrospective dosimetry. As a physical method, EPR analysis of biological material measures the quantity of free radicals generated in the material from the interaction of radiation and material. Since the later 80s, in many countries, EPR dosimetry with tooth enamel has been studied and applied for the retrospective dosimetry. In the consideration of the biological materials for EPR dosimetry, human fingernail, hair, bone and tooth are generally considered. The tooth can be separated as enamel, dentine and cementum. Among the three parts, enamel shows the best sensitivity to the absorbed dose and is most widely used. In this study, the characteristics of tooth enamel for EPR dosimetry is examined and experimented. At the experiment, for easy separation, tooth was cut into 4 parts and then each part is treated by ultrasonic vibration in NaOH liquid to reduce mechanically induced noise in the corresponding signal. After the separation of the enamel from dentine, background EPR signal is measured and then radiation-induced EPR spectrum is estimated

  1. Compartmental study of biological systems

    International Nuclear Information System (INIS)

    Moretti, J.L.

    1975-01-01

    The compartmental analysis of biological system is dealt with on several chapters devoted successively to: terminology; a mathematical and symbolic account of a system at equilibrium; different compartment systems; analysis of the experimental results. For this it is pointed out that the application of compartmental systems to biological phenomena is not always without danger. Sometimes the compartmental system established in a reference subject fails to conform in the patient. The compartments can divide into two or join together, completely changing the aspect of the system so that parameters calculated with the old model become entirely false. The conclusion is that the setting up of a compartmental system to represent a biological phenomenon is a tricky undertaking and the results must be constantly criticized and questioned [fr

  2. Radiation dosimetry in radiotherapy with internal emitters

    International Nuclear Information System (INIS)

    Stabin, Michael G.

    1997-01-01

    Full text. Radiation dosimetry radionuclides are currently being labeled to various biological agents used in internal emitter radiotherapy. This talk will review the various technologies and types of radiolabel in current use, with focus on the characterization of the radiation dose to the various important tissues of the body. Methods for obtaining data, developing kinetic models, and calculating radiation doses will be reviewed. Monoclonal antibodies are currently being labeled with both alpha and beta emitting radionuclides in attempts to find effective agents against cancer. Several radionuclides are also being used as bone pain palliation agents. These agents must be studied in clinical trials to determine the biokinetics and radiation dosimetry prior to approval for general use. In such studies, it is important to ensure the collection of the appropriate kinds of data and to collect the data at appropriate time intervals. The uptake and retention of activity in all significant source organs and in excreta be measured periodically (with at least 2 data points phase of uptake or clearance). Then, correct dosimetry methods must be applied - the best available methods for characterizing the radionuclide kinetic and for estimating the dosimetry in the various organs of the body especially the marrow, should be used. Attempts are also under way to develop methods for estimating true patient-specific dosimetry. Cellular and animal studies are also. Valuable in evaluating the efficacy of the agents in shrinking or eliminating tumors; some results from such studies will also be discussed. The estimation of radiation doses to patients in therapy with internal emitters involves several complex phases of analysis. Careful attention to detail and the use of the best available methods are essential to the protection of the patient and a successful outcome

  3. Dosimetry in life sciences

    International Nuclear Information System (INIS)

    1975-01-01

    The uses of radiation in medicine and biology have grown in scope and diversity to make the Radiological Sciences a significant factor in both research and medical practice. Of critical importance in the applications and development of biomedical and radiological techniques is the precision with which the dose may be determined at all points of interest in the absorbing medium. This has developed as a result of efficacy of investigations in clinical radiation therapy, concern for patient safety and diagnostic accuracy in diagnostic radiology and the advent of clinical trials and research into the use of heavily ionizing radiations in biology and medicine. Since the last IAEA Symposium on Dosimetry Techniques applied to Agriculture, Industry, Biology and Medicine, held in Vienna in 1972, it has become increasingly clear that advances in the techniques and hardware of biomedical dosimetry have been rapid. It is for these reasons that this symposium was organized in a concerted effort to focus on the problems, developments and areas of further research in dosimetry in the Life Sciences. (author)

  4. Dosimetry in life sciences

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-06-15

    The uses of radiation in medicine and biology have grown in scope and diversity to make the Radiological Sciences a significant factor in both research and medical practice. Of critical importance in the applications and development of biomedical and radiological techniques is the precision with which the dose may be determined at all points of interest in the absorbing medium. This has developed as a result of efficacy of investigations in clinical radiation therapy, concern for patient safety and diagnostic accuracy in diagnostic radiology and the advent of clinical trials and research into the use of heavily ionizing radiations in biology and medicine. Since the last IAEA Symposium on Dosimetry Techniques applied to Agriculture, Industry, Biology and Medicine, held in Vienna in 1972, it has become increasingly clear that advances in the techniques and hardware of biomedical dosimetry have been rapid. It is for these reasons that this symposium was organized in a concerted effort to focus on the problems, developments and areas of further research in dosimetry in the Life Sciences. (author)

  5. Appendix U: benthic biological studies

    International Nuclear Information System (INIS)

    Hessler, R.R.

    1981-01-01

    Characterization of the biology and standing crop of the benthic organisms is divided into two major categories: (1) those organisms (sessile or with limited mobility) that live on or within the sediment (infauna); and (2) highly mobile organisms that have contact (if only occasionally) with the sediment (benthopelagic organisms). At this time our studies of benthopelagic organisms are restricted to amphipods. The amphipods trapped at MPG-I (30 to 31 0 N, 159 0 W) in 1978 have been sorted to species and compared with those trapped at Climax II (28 0 N, 155 to 156 0 W) in 1977. The species composition is the same at both stations and the numerical representation of the various species appears to be equivalent. Instar categories based on morphological and size criteria have been determined for Eurythenes gryllus. Comparison of the size range of the instar categories, morphological characters and female to male ratio show no detectable differences in E. gryllus from the two areas. Individuals of one of the smaller species of amphipods (Paralicella caperesca) were trapped at 710 m above the sediment, demonstrating that although the primary range of this species is 0-1 m off the bottom, it is capable of wide bathymetric movements. Males mature at a much smaller size (7 cm vs 11.5 cm) than females. Females appear to breed only once while males seem to be reproductively mature for several instars. After attaining maturity, male growth decreases to almost half the previous rate, and the time interval between molts appears to increase substantially. Females approximate a linear growth rate throughout their instar stages. The data are insufficient to determine if a decrease in growth rate occurs at the molt to maturity (female 14). The apparent difference in the time to maturity for males and females results in a high number of mature males present in the population to fertilize relatively few females

  6. Tritium biological effects and perspective of the biological study

    International Nuclear Information System (INIS)

    Komatsu, Kenshi

    1998-01-01

    Since tritium is an emitter of weak β-rays (5.7keV) and is able to bind to DNA, i.e., the most important genome component, the biological effects should be expected to be more profound than that of X-rays and γ-rays. When carcinogenesis, genetical effects and the detriments for fetus and embryo were used as a biological endpoint, most of tritium RBE (relative biological effectiveness) ranged from 1 to 2. The tritium risk in man could be calculated from these RBEs and γ-ray risk for human exposure, which are obtained mainly from the data on Atomic Bomb survivors. However, the exposure modality from environmental tritium should be a chronic irradiation with ultra low dose rate or a fractionated irradiation. We must estimate the tritium effect in man based on biological experiments alone, due to lack of such epidemiological data. Low dose rate experiment should be always accompanied by the statistical problem of data, since their biological effects are fairy low, and they should involve a possible repair system, such as adaptive response (or hormesis effect) and 'Kada effect' observed in bacteria. Here we discuss future works for the tritium assessment in man, such as (1) developing a high radiation sensitive assay system with rodent hybrid cells containing a single human chromosome and also (2) study on mammal DNA repair at molecular levels using a radiosensitive hereditary disease, Nijmegen Breakage Syndrome. (author)

  7. TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D. [Toshiba America Medical Systems (United States)

    2015-06-15

    Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

  8. TU-E-201-02: Eye Lens Dosimetry From CT Perfusion Studies

    International Nuclear Information System (INIS)

    Zhang, D.

    2015-01-01

    Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

  9. Clinical dosimetry

    International Nuclear Information System (INIS)

    Rassow, J.

    1973-01-01

    The main point of this paper on clinical dosimetry which is to be understood here as application of physical dosimetry on accelerators in medical practice, is based on dosimetric methodics. Following an explanation of the dose parameters and description of the dose distribution important for clinical practice as well as geometric irradiation parameters, the significance of a series of physical parameters such as accelerator energy, surface energy of average stopping power etc. is dealt with in detail. Following a section on field homogenization with bremsstrahlung and electron radiation, details on dosimetry in clinical practice are given. Finally, a few problems of dosemeter or monitor calibration on accelerators are described. The explanations are supplemented by a series of diagrams and tables. (ORU/LH) [de

  10. A combined experimental and numerical study on upper airway dosimetry of inhaled nanoparticles from an electrical discharge machine shop.

    Science.gov (United States)

    Tian, Lin; Shang, Yidan; Chen, Rui; Bai, Ru; Chen, Chunying; Inthavong, Kiao; Tu, Jiyuan

    2017-07-12

    Exposure to nanoparticles in the workplace is a health concern to occupational workers with increased risk of developing respiratory, cardiovascular, and neurological disorders. Based on animal inhalation study and human lung tumor risk extrapolation, current authoritative recommendations on exposure limits are either on total mass or number concentrations. Effects of particle size distribution and the implication to regional airway dosages are not elaborated. Real time production of particle concentration and size distribution in the range from 5.52 to 98.2 nm were recorded in a wire-cut electrical discharge machine shop (WEDM) during a typical working day. Under the realistic exposure condition, human inhalation simulations were performed in a physiologically realistic nasal and upper airway replica. The combined experimental and numerical study is the first to establish a realistic exposure condition, and under which, detailed dose metric studies can be performed. In addition to mass concentration guided exposure limit, inhalation risks to nano-pollutant were reexamined accounting for the actual particle size distribution and deposition statistics. Detailed dosimetries of the inhaled nano-pollutants in human nasal and upper airways with respect to particle number, mass and surface area were discussed, and empirical equations were developed. An astonishing enhancement of human airway dosages were detected by current combined experimental and numerical study in the WEDM machine shop. Up to 33 folds in mass, 27 folds in surface area and 8 folds in number dosages were detected during working hours in comparison to the background dosimetry measured at midnight. The real time particle concentration measurement showed substantial emission of nano-pollutants by WEDM machining activity, and the combined experimental and numerical study provided extraordinary details on human inhalation dosimetry. It was found out that human inhalation dosimetry was extremely sensitive

  11. Assessment of radiation damage - the need for a multi-parametric and integrative approach with the help of both clinical and biological dosimetry

    International Nuclear Information System (INIS)

    Meineke, Viktor

    2008-01-01

    Full text: Accidental exposure to ionising radiation leads to a damage on different levels of the biological organization of the organism. Depending on exposure conditions, such as nature of radiation, time and affected organs and organ systems, the clinical endpoint of radiation damage and the resulting acute and chronic radiation syndromes may vary to a great extent. Exposure situations range from pure localised radiation scenarios and partial body exposures up to whole body exposures. Therefore clinical pictures vary from localized radiation injuries up to the extreme situation of a radiation-induced multi-organ involvement and failure requiring immediate, intensive and interdisciplinary medical treatment. These total different and complex clinical situations not only show up most different clinical diagnostic and therapeutic aspects but necessarily due to different levels of the underlying biological damage, biological indicators of effects may vary to a wide extent. This fact means that an exact assessment of the extent of radiation damage within individual patients can only be performed when taking into consideration both clinical signs and symptoms as well as different biological indicators. Among the clinical indicators, routine laboratory parameters such as blood counts and the documentation of clinical signs and symptoms (such as the METREPOL system) are the key parameters, whereas the dicentric assay, the gold standard for biological dosimetry, but also methods under development such as the gamma-H2Ax focus assay or the estimation of variations of gene expression have to be taken into account. Each method provides best results in different situations, or in other words, there are methods that work better in a specific exposure condition or at a given time of examination (e.g. time after exposure) than others. Some methods show up results immediately, others require days to weeks until results are available for clinical decision making. Therefore to

  12. Contribution of new cytogenetic techniques in the estimations of old irradiations in retrospective biological dosimetry; Apport des nouvelles techniques de cytogenetiques dans l'estimation des irradiations anciennes en dosimetrie biologique retrospective

    Energy Technology Data Exchange (ETDEWEB)

    Pouzoulet, F

    2007-10-15

    The objective of this study was to answer three questions: if the translocations are steady: the results have shown that the translocations even if they are not obligatory steady can be used in retrospective dosimetry. Furthermore, it appeared important to consider the complex translocations in view of their relative stability and complementary information they bring ( quality of radiation, received dose). The second question is what contribution of the M-F.I.S.H. in the translocations analysis in comparison with the F.I.S.H.-3: we have shown that the M-F.I.S.H. would allow to raise the whole of doubt due to a partial genome observation. that has for effect to increase the precision of the analysis and that what ever be the received dose. The third question is if there are differences between the chromosomal aberrations generated by x radiation of 50 keV and by gamma radiation from cobalt-60: yes, the low energy photons generate more translocations than the photons coming from cobalt-60. But they generate less dicentrics. this difference comes from the way the energy is deposited that leads to a more important formation of complex and multiple translocations with the low energy photons. this could constitute a problem in the use of low energy photons in radiotherapy. it would seem that the simple translocations rate is not influenced by the photons energy. (N.C.)

  13. Contribution of new cytogenetic techniques in the estimations of old irradiations in retrospective biological dosimetry; Apport des nouvelles techniques de cytogenetiques dans l'estimation des irradiations anciennes en dosimetrie biologique retrospective

    Energy Technology Data Exchange (ETDEWEB)

    Pouzoulet, F

    2007-10-15

    The objective of this study was to answer three questions: if the translocations are steady: the results have shown that the translocations even if they are not obligatory steady can be used in retrospective dosimetry. Furthermore, it appeared important to consider the complex translocations in view of their relative stability and complementary information they bring ( quality of radiation, received dose). The second question is what contribution of the M-F.I.S.H. in the translocations analysis in comparison with the F.I.S.H.-3: we have shown that the M-F.I.S.H. would allow to raise the whole of doubt due to a partial genome observation. that has for effect to increase the precision of the analysis and that what ever be the received dose. The third question is if there are differences between the chromosomal aberrations generated by x radiation of 50 keV and by gamma radiation from cobalt-60: yes, the low energy photons generate more translocations than the photons coming from cobalt-60. But they generate less dicentrics. this difference comes from the way the energy is deposited that leads to a more important formation of complex and multiple translocations with the low energy photons. this could constitute a problem in the use of low energy photons in radiotherapy. it would seem that the simple translocations rate is not influenced by the photons energy. (N.C.)

  14. Radiation exposure and dosimetry in transplant patients due to Nuclear Medicine studies

    International Nuclear Information System (INIS)

    El-Maghraby, T. A. F.; Cairo Univ., Cairo; Camps, J. A. J.; Geleyns, J.; Pauwels, E. K. J.

    2000-01-01

    Organ transplantation is now an accepted method of therapy for treating patients with end stage failure of kidneys, liver, heart or lung. Nuclear Medicine may provide functional data and semi-quantitative parameters. However, one serious factor that hampers the use of nuclear medicine procedures in transplant patients is the general clinical concern about radiation exposure to the patient. This lead the researcher to discuss the effective doses and radiation dosimetry associated with radionuclide procedures used in the management and follow-up of transplant patients. A simple way to place the risk associated with Nuclear Medicine studies in an appropriate context is to compare the dose with that received from more familiar source of exposure such as from a diagnostic X-ray procedure. The radiation dose for the different radiopharmaceuticals used to study transplant organ function ranges between 0.1 and 5.3 mSv which is comparable to X-ray procedures with the exception of 201 Tl and 111 In-antimyosin. Thus Nuclear Medicine studies do not bear a higher radiation risk than the often used X-ray studies in transplant patients

  15. Study the Effect of Gamma Radiation on some Solid and Polymeric Materials and Its Possible Applications in Radiation Dosimetry

    International Nuclear Information System (INIS)

    El-Shawadfy, E.R.

    2015-01-01

    Dyed solid materials (films and gels) and dyed solutions dosimeters have wide-spread applications in radiation processing for installation process qualification and routine dose control for both gamma rays and electron beam irradiation. These film dosimeters have been introduced for low- and high-dose monitoring. The introduction of new types of dosimeters is due to the effort of seeking for more reliable, more stable, simpler and cheaper systems as routine dosimeters and/or label dosimeters. The main objective of this work is to study the possibility of preparing dyed solid polymeric materials (dyed films- dyed gels) and dyed solutions, and study the dosimetric studies for the prepared materials. The results obtained in this work can be summarized in the following: Section (1): Deals with the investigation of prepared three dosimetry systems based on Toludine Blue O (TBO) dye, to make them readily usable in high and low-radiation dosimetry applications (e.g. sterilization of medical products, sterilization of pharmaceutical products and polymer modification). This section is divided into three parts: Part I: This part includes the preparation and development of polymeric films for high-dose dosimetry applications, these films are based on poly (vinyl alcohol) dyed with TBO. These flexible plastic film dosimeters are bleached when exposed to gamma-ray photons (i.e. from blue to colorless) at λmax=633 nm. The radiation chemical yield (G-Value) for different concentrations of the dye as well as the dye with additive substances (chloral hydrate) was calculated. It was found that these films are highly stable for long time before and after irradiation under different storage conditions. The response of these films is not affected by humidity change in the range of relative humidity (0-56%). PVA films dyed with TBO are suitable in the dose range from 1-150 kGy. These properties suggest them to be useful for routine and dose mapping in sterilization range of radiation

  16. Workshop Report on Atomic Bomb Dosimetry--Residual Radiation Exposure: Recent Research and Suggestions for Future Studies

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-06

    There is a need for accurate dosimetry for studies of health effects in the Japanese atomic bomb survivors because of the important role that these studies play in worldwide radiation protection standards. International experts have developed dosimetry systems, such as the Dosimetry System 2002 (DS02), which assess the initial radiation exposure to gamma rays and neutrons but only briefly consider the possibility of some minimal contribution to the total body dose by residual radiation exposure. In recognition of the need for an up-to-date review of the topic of residual radiation exposure in Hiroshima and Nagasaki, recently reported studies were reviewed at a technical session at the 57th Annual Meeting of the Health Physics Society in Sacramento, California, 22-26 July 2012. A one-day workshop was also held to provide time for detailed discussion of these newer studies and to evaluate their potential use in clarifying the residual radiation exposures to the atomic-bomb survivors at Hiroshima and Nagasaki. Suggestions for possible future studies are also included in this workshop report.

  17. A comprehensive tool for image-based generation of fetus and pregnant women mesh models for numerical dosimetry studies

    International Nuclear Information System (INIS)

    Dahdouh, S; Serrurier, A; De la Plata, J-P; Anquez, J; Angelini, E D; Bloch, I; Varsier, N; Wiart, J

    2014-01-01

    Fetal dosimetry studies require the development of accurate numerical 3D models of the pregnant woman and the fetus. This paper proposes a 3D articulated fetal growth model covering the main phases of pregnancy and a pregnant woman model combining the utero-fetal structures and a deformable non-pregnant woman body envelope. The structures of interest were automatically or semi-automatically (depending on the stage of pregnancy) segmented from a database of images and surface meshes were generated. By interpolating linearly between fetal structures, each one can be generated at any age and in any position. A method is also described to insert the utero-fetal structures in the maternal body. A validation of the fetal models is proposed, comparing a set of biometric measurements to medical reference charts. The usability of the pregnant woman model in dosimetry studies is also investigated, with respect to the influence of the abdominal fat layer. (paper)

  18. Biological dosimetry - a Bayesian approach in the presentation of the uncertainty of the estimated dose in cases of exposure to low dose radiation

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Zaretzky, A.

    2010-01-01

    Biodosimetry laboratory experience has shown that there are limitations in the existing statistical methodology. Statistical difficulties generally occur due to the low number of aberrations leading to large uncertainties for dose estimation. Some problems derived from limitations of the classical statistical methodology, which requires that chromosome aberration yields be considered as something fixed and consequently provides a deterministic dose estimation and associated confidence limits. On the other hand, recipients of biological dosimetry reports, including medical doctors, regulators and the patients themselves may have a limited comprehension of statistics and of informed reports. Thus, the objective of the present paper is to use a Bayesian approach to present the uncertainty on the estimated dose to which a person could be exposed, in the case of low dose (occupational doses) radiation exposure. Such methodology will allow the biodosimetrists to adopt a probabilistic approach for the cytogenetic data analysis. At present, classical statistics allows to produce a confidence interval to report such dose, with a lower limit that could not detach from zero. In this situation it becomes difficult to make decisions as they could impact on the labor activities of the worker if an exposure exceeding the occupational dose limits is inferred. The proposed Bayesian approach is applied to occupational exposure scenario to contribute to take the appropriate radiation protection measures. (authors) [es

  19. A comparative study of some aspects of radiation protection and dosimetry procedures. Pt. 1 and 2

    International Nuclear Information System (INIS)

    Drexler, G.; Goeksu, H.Y.; Johns, T.F.

    1987-10-01

    A study has been made of the procedures used in the Member States of the European Communities for dealing with certain practical and administrative aspects of radiation protection of occupationally exposed persons, and especially of the methods and procedures used in personnel dosimetry. It was found that the different states have adopted quite different methods for dealing with some of these problems, the method chosen seeming to depend on the size of the country and the extent and timing of its involvement with nuclear power developments; but although the different countries have adopted different methods of control, as far as we can judge they have all been reasonably effective in achieving adequate control of occupational exposures. Nevertheless, there are still issues that each country could probably learn and perhaps improve its own procedure by making a more careful study of the way in which other countries deal with these problems. Therefore the study was extended to cover the USA and Japan in order to facilitate such comparisons and improvements. (orig.)

  20. Monte Carlo study of correction factors for the use of plastic phantoms in clinical electron dosimetry

    International Nuclear Information System (INIS)

    Araki, Fujio

    2007-01-01

    In some recent dosimetry protocols, plastic is allowed as a phantom material for the determination of an absorbed dose to water in electron beams, especially for low energy with beam qualities R 50 2 . In electron dosimetry with plastic, a depth-scaling factor, c pl , and a chamber-dependent fluence correction factor, h pl , are needed to convert the dose measured at a water-equivalent reference depth in plastic to a dose at a reference depth in water. The purpose of this study is to calculate correction factors for the use of plastic phantoms for clinical electron dosimetry using the EGSnrc Monte Carlo code system. RMI-457 and WE-211 were investigated as phantom materials. First the c pl values for plastic materials were calculated as a function of a half-value depth of maximum ionization, I 50 , in plastic. The c pl values for RMI-457 and WE-211 varied from 0.992 to 1.002 and from 0.971 to 0.979, respectively, in a range of nominal energies from 4 MeV to 18 MeV, and varied slightly as a function of I 50 in plastic. Since h pl values depend on the wall correction factor, P wall , of the chamber used, they are evaluated using a pure electron fluence correction factor, φ pl w , and P wall w and P wall pl for a combination of water or plastic phantoms and plane-parallel ionization chambers (NACP-02, Markus and Roos). The φ pl w and P wall (P wall w and P wall pl ) values were calculated as a function of the water-equivalent depth in plastic materials and at a reference depth as a function of R 50 in water, respectively. The φ pl w values varied from 1.024 at 4 MeV to 1.013 at 18 MeV for RMI-457, and from 1.025 to 1.016 for WE-211. P wall w values for plane-parallel chambers showed values in the order of 1.5% to 2% larger than unity at 4 MeV, consistent with earlier results. The P wall pl values of RMI-457 and WE-211 were close to unity for all the energy beams. Finally, calculated h pl values of RMI-457 ranged from 1.009 to 1.005, from 1.010 to 1.003 and from 1

  1. Environmental dosimetry

    International Nuclear Information System (INIS)

    Gold, R.

    1977-01-01

    For more than 60 years, natural radiation has offered broad opportunities for basic research as evidenced by many fundamental discoveries. Within the last decade, however, dramatic changes have occurred in the motivation and direction of this research. The urgent need for economical energy sources entailing acceptably low levels of environmental impact has compelled the applied aspects of our radiation environment to become overriding considerations. It is within this general framework that state-of-the-art environmental dosimetry techniques are reviewed. Although applied motivation and relevance underscores the current milieu for both reactor and environmental dosimetry, a perhaps even more unifying force is the broad similarity of reactor and environmental radiation fields. In this review, a comparison of these two mixed radiation fields is presented stressing the underlying similarities that exist. On this basis, the evolution of a strong inner bond between dosimetry methods for both reactor and environmental radiation fields is described. The existence of this bond will be illustrated using representative examples of observed spectra. Dosimetry methods of particularly high applicability for both of these fields are described. Special emphasis is placed on techniques of high sensitivity and absolute accuracy which are capable of resolving the components of these mixed radiation fields

  2. Nuclear biological studies in France

    International Nuclear Information System (INIS)

    Coursaget, J.

    1961-01-01

    On the occasion of a colloquium on radiobiological research programmes, a number of documents dealing with French accomplishments and projects in this field were collected together. We felt that it would be useful to assemble these papers in one report; although they are brief and leave gaps to be filled in, they provide certain data, give an overall view of the situation, and can also suggest a rough plan for the general policy to adopt in the field of 'nuclear' biological research; i.e. research based on the nuclear tracer method or devoted to the action of ionising radiations. (author) [fr

  3. A review of contributions of human tissue studies to biokinetics, bio-effects and dosimetry of plutonium in man

    International Nuclear Information System (INIS)

    Kathren, R. L.

    2004-01-01

    This paper briefly reviews the contributions made by human tissue studies to improved understanding of the biokinetics, dosimetry and potential bio-effects of plutonium in man. It includes consideration of tissue donations from both environmental and occupational populations, along with a brief history of human experience with plutonium and consideration of the bio-ethical aspects of post-mortem human tissue sampling. (authors)

  4. Study of the replacement correction factors for ionization chamber dosimetry by Monte Carlo simulations

    Science.gov (United States)

    Wang, Lilie

    In ionization chamber radiation dosimetry, the introduction of the ion chamber into medium will unavoidably distort the radiation field near the chamber because the chamber cavity material (air) is different from the medium. A replacement correction factor, Prepl was introduced in order to correct the chamber readings to give an accurate radiation dose in the medium without the presence of the chamber. Generally it is very hard to measure the values of Prepl since they are intertwined with the chamber wall effect. In addition, the P repl values always come together with the stopping-power ratio of the two media involved. This makes the problem of determining the P repl values even more complicated. Monte Carlo simulation is an ideal method to investigate the replacement correction factors. In this study, four different methods of calculating the values of Prepl by Monte Carlo simulation are discussed. Two of the methods are designated as 'direct' methods in the sense that the evaluation of the stopping-power ratio is not necessary. The systematic uncertainties of the two direct methods are estimated to be about 0.1-0.2% which comes from the ambiguous definition of the energy cutoff Delta used in the Spencer-Attix cavity theory. The two direct methods are used to calculate the values of P repl for both plane-parallel chambers and cylindrical thimble chambers in either electron beams or photon beams. The calculation results are compared to measurements. For electron beams, good agreements are obtained. For thimble chambers in photon beams, significant discrepancies are observed between calculations and measurements. The experiments are thus investigated and the procedures are simulated by the Monte Carlo method. It is found that the interpretation of the measured data as the replacement correction factors in dosimetry protocols are not correct. In applying the calculation to the BIPM graphite chamber in a 60Co beam, the calculated values of P repl differ from those

  5. External dosimetry - Applications to radiation protection

    International Nuclear Information System (INIS)

    Faussot, Alain

    2011-01-01

    Dosimetry is the essential component of radiation protection. It allows to determine by calculation and measurement the absorbed dose value, i.e. the energy amounts deposited in matter by ionizing radiations. It deals also with the irradiation effects on living organisms and with their biological consequences. This reference book gathers all the necessary information to understand and master the external dosimetry and the metrology of ionizing radiations, from the effects of radiations to the calibration of radiation protection devices. The first part is devoted to physical dosimetry and allows to obtain in a rigorous manner the mathematical formalisms leading to the absorbed dose for different ionizing radiation fields. The second part presents the biological effects of ionizing radiations on living matter and the determination of a set of specific radiation protection concepts and data to express the 'risk' to develop a radio-induced cancer. The third part deals with the metrology of ionizing radiations through the standardized study of the methods used for the calibration of radiation protection equipments. Some practical exercises with their corrections are proposed at the end of each chapter

  6. Dosimetry study for a new in vivo X-ray fluorescence (XRF) bone lead measurement system

    International Nuclear Information System (INIS)

    Nie Huiling; Chettle, David; Luo Liqiang; O'Meara, Joanne

    2007-01-01

    A new 109 Cd γ-ray induced bone lead measurement system has been developed to reduce the minimum detectable limit (MDL) of the system. The system consists of four 16 mm diameter detectors. It requires a stronger source compared to the 'conventional' system. A dosimetry study has been performed to estimate the dose delivered by this system. The study was carried out by using human-equivalent phantoms. Three sets of phantoms were made to estimate the dose delivered to three age groups: 5-year old, 10-year old and adults. Three approaches have been applied to evaluate the dose: calculations, Monte Carlo (MC) simulations, and experiments. Experimental results and analytical calculations were used to validate MC simulation. The experiments were performed by placing Panasonic UD-803AS TLDs at different places in phantoms that representing different organs. Due to the difficulty of obtaining the organ dose and the whole body dose solely by experiments and traditional calculations, the equivalent dose and effective dose were calculated by MC simulations. The result showed that the doses delivered to the organs other than the targeted lower leg are negligibly small. The total effective doses to the three age groups are 8.45/9.37 μSv (female/male), 4.20 μSv, and 0.26 μSv for 5-year old, 10-year old and adult, respectively. An approval to conduct human measurements on this system has been received from the Research Ethics Board based on this research

  7. Determination of electrical characteristics of body tissues for computational dosimetry studies

    International Nuclear Information System (INIS)

    Silva, Rafael Monteiro da Cruz; Domingues, Luis Adriano M.C.; Neto, Athanasio Mpalantinos; Barbosa, Carlos Ruy Nunez

    2008-01-01

    Increasing public concern about human exposure to electromagnetic fields led to the development of International Exposure Standards, which reflect the actual scientific knowledge on this subject. Existing exposure limits (reference levels), are based on maximum admissible fields or induced currents densities inside human bodies, called basic restrictions. Since those physical quantities can not be readily measured, they must be estimated using techniques of computational dosimetry. These techniques rely on accurate computational modelling of human bodies to establish the relation of external field (electric / magnetic) to induced current (internal field). Nowadays the models available for human body simulation (FEM, FDM,...) are quite accurate, specially when using geometric discretization obtained from medical imaging techniques, however the determination of tissues characteristics (permittivity and conductivity) is still an issue to be dealt with. In current studies the electrical characteristics (permittivity and conductivity) of body tissues are based on values which were obtained from measurements done on tissue simples obtained from dead bodies. However those values may not represent adequately the behaviour of living tissues. In this paper a research designed to characterize the permittivity of human body tissues is presented, consisting of measurements and simulations designed to determine, using indirect methods, the electrical behaviour of living tissues. A study of exposure assessment on a real high voltage transmission line in Brazil, using measured permittivity values combined with a finite element model of the human body is presented in the panel. (author)

  8. Atomic bomb dosimetry for epidemiological studies of survivors in Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Maruyama, Takashi

    1986-01-01

    Better atomic bomb (A-bomb) radiation dose estimates with a higher accuracy are required for the epidemiological studies in Hiroshima and Nagasaki. Several scientists have tried to evaluate the free-in-air gamma ray and neutron dose and some weighting factors such as house shielding and body shielding. Since 1965, the tentative 1965 dose (T65D) has been widely used as the basic data for the dose determination of A-bomb survivors in epidemiological studies. In 1976, however, the reevaluation of the T65D dose was proposed by an American scientist who calculated the A-bomb doses on the basis of declassified data on the radiation spectra of the A-bomb. The development of computer technology made it possible to perform complicated dosecalculations for the Hiroshima and Nagasaki bombs. This paper describes the history of A-bomb dosimetry, reviews some issues in the determination of T65D, and discusses the necessity of reassessment of A-bomb dose and the expected values for survivors. (author)

  9. Atomic bomb dosimetry for epidemiological studies of survivors in Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Maruyama, T.

    1986-01-01

    Better atomic bomb (A-bomb) radiation dose estimates with a higher accuracy are required for the epidemiological studies in Hiroshima and Nagasaki. Several scientists have tried to evaluate the free-in-air gamma ray and neutron dose and some weighting factors such as house shielding and body shielding. Since 1965, the tentative 1965 dose (T65D) had been widely used as the basic data for the dose determination of A-bomb survivors in epidemiological studies. In 1976, however, the reevaluation of the T65D dose was proposed by an American scientist who calculated the A-bomb doses on the basis of declassified data on the radiation spectra of the A-bomb. The development of computer technology made it possible to perform complicated dosecalculations for the Hiroshima and Nagasaki bombs. This paper describes the history of A-bomb dosimetry, reviews some issues in the determination of T65D, and discusses the necessity of reassessment of A-bomb dose and the expected values for survivors

  10. In vivo thermoluminescent dosimetry in studies of helicoid computed tomography and excretory urogram; Dosimetria termoluminiscente In vivo en estudios de tomografia computada helicoidal y urograma excretor

    Energy Technology Data Exchange (ETDEWEB)

    Cruz C, D.; Azorin N, J. [UAM-I, 09340 Mexico D.F. (Mexico); Saucedo A, V.M.; Barajas O, J.L. [Unidad de Especialidades Medicas, Secretaria de la Defensa Nacional, 11500 Mexico D.F. (Mexico)

    2005-07-01

    The dosimetry is the field of measurement of the ionizing radiations. It final objective is to determine the 'absorbed dose' for people. The dosimetry is vital in the radiotherapy, the radiological protection and the treatment technologies by irradiation. Presently work, we develop 'In vivo' dosimetry, in exposed patients to studies of helical computed tomography and excretory urogram. The dosimetry 'in vivo' was carried out in 20 patients selected aleatorily, for each medical study. The absorbed dose was measured in points of interest located in crystalline, thyroid, chest and abdomen of each patient, by means of thermoluminescent dosemeters (TLD) LiF: Mg,Cu,P + Ptfe of national fabrication. Also it was quantified the dose in the working area. (Author)

  11. CaSO4:Dy and/or Tm: study of its properties for dosimetry application

    International Nuclear Information System (INIS)

    Ferreira, M.M.

    1979-01-01

    In order obtain in practical and cheap solid state dosimeter with high sensitivity, a technique initially developed to cold press a mixture of suitable materials in their powder form sensitive to radiation. The material initially used was natural CaF 2 (fluorite) for this salt was extensively studied in radiation dosimetry since it shows a thermoluminescent (TL) effect after radiation. However, natural calcium fluorite shows two main disadvantages: its high senstivity to room light and the impossibility to control its impurity content due to its natural origin. Calcium sulphate was thus used as a good substitute of fluorite. Rare earths doped calcium sulphate shows a high TL sensitivity and is not disturbed by light. It is also easily obtained in the laboratory under controlled conditions so to get reproducible impurity content. The best dosimeters that can be produced with rare earth doped calcium sulphate are CaSO 4 :Dy and CaSO 4 :Tm. Calcium sulphate, simultaneously doped with Tm and Dy was produced and 100% increase was obtained in the TL sensitivity when compared with the individually are earth doped calcium sulphate. (Author) [pt

  12. Study of runaway electrons using dosimetry of hard x-ray radiations in Damavand tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Rasouli, C.; Pourshahab, B.; Rasouli, H. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of); Hosseini Pooya, S. M.; Orouji, T. [Radiation Application Research School, Nuclear Science and Technology Research Institute, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of)

    2014-05-15

    In this work several studies have been conducted on hard x-ray emissions of Damavand tokamak based on radiation dosimetry using the Thermoluminescence method. The goal was to understand interactions of runaway electrons with plasma particles, vessel wall, and plasma facing components. Total of 354 GR-200 (LiF:Mg,Cu,P) thermoluminescence dosimeter (TLD) crystals have been placed on 118 points – three TLDs per point – to map hard x-ray radiation doses on the exterior of the vacuum vessel. Results show two distinctive levels of x-ray radiations doses on the exterior of the vessel. The low-dose area on which measured dose is about 0.5 mSv/shot. In the low-dose area there is no particular component inside the vessel. On the contrary, on high-dose area of the vessel, x-ray radiations dose exceeds 30 mSv/shot. The high-dose area coincides with the position of limiters, magnetic probe ducts, and vacuum vessel intersections. Among the high-dose areas, the highest level of dose is measured in the position of the limiter, which could be due to its direct contact with the plasma column and with runaway electrons. Direct collisions of runaway electrons with the vessel wall and plasma facing components make a major contribution for production of hard x-ray photons in Damavand tokamak.

  13. Feasibility study of the real-time IMRT dosimetry using a scintillation screen

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sang Wook; Yi, Byong Yong; Ko, Young Eun [Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of)] (and others)

    2004-03-15

    To study the feasibility of verifying real-time 2-D dose distribution measurement system with the scintillation screen for the quality assurance. The water phantom consisted of a scintillation screen (LANEX fast screen, Kodak, USA) that was axially located in the middle of an acrylic cylinder with a diameter of 25 cm. The charge-coupled device (CCD) camera was attached to the phantom in order to capture the visible light from the scintillation screen. To observe the dose distribution in real time, the intensity of the light from the scintillator was converted to a dosage. The isodose contours of the calculations from RTP and those of the measurements using the scintillation screen were compared for the arc therapy and the intensity modulated radiation therapy (IMRT). The kernel, expressed as a multiplication of two error functions, was obtained in order to correct the sensitivity of the CCD of the camera and the scintillation screen. When comparing the calculated isodose and measured isodose, a discrepancy of less than 8 mm in the high dose region was observed. Using the 2-D dosimetry system, the relationship between the light and the dosage could be found, and real-time verification of the dose distribution was feasible.

  14. Feasibility study of the real-time IMRT dosimetry using a scintillation screen

    International Nuclear Information System (INIS)

    Lim, Sang Wook; Yi, Byong Yong; Ko, Young Eun

    2004-01-01

    To study the feasibility of verifying real-time 2-D dose distribution measurement system with the scintillation screen for the quality assurance. The water phantom consisted of a scintillation screen (LANEX fast screen, Kodak, USA) that was axially located in the middle of an acrylic cylinder with a diameter of 25 cm. The charge-coupled device (CCD) camera was attached to the phantom in order to capture the visible light from the scintillation screen. To observe the dose distribution in real time, the intensity of the light from the scintillator was converted to a dosage. The isodose contours of the calculations from RTP and those of the measurements using the scintillation screen were compared for the arc therapy and the intensity modulated radiation therapy (IMRT). The kernel, expressed as a multiplication of two error functions, was obtained in order to correct the sensitivity of the CCD of the camera and the scintillation screen. When comparing the calculated isodose and measured isodose, a discrepancy of less than 8 mm in the high dose region was observed. Using the 2-D dosimetry system, the relationship between the light and the dosage could be found, and real-time verification of the dose distribution was feasible

  15. ESR dosimetry study for the residents of Kazakhstan exposed to radioactive fallout on 24, August 1956

    Energy Technology Data Exchange (ETDEWEB)

    Zhumadilov, K., E-mail: kassym@hiroshima-u.ac.jp [Research Institute for Radiation Biology and Medicine, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553 (Japan); Ivannikov, A. [Medical Radiological Research Center, Obninsk 249036 (Russian Federation); Zharlyganova, D. [Astana Medical University, 51a, Beibitshilik str., Astana 010000 (Kazakhstan); Zhumadilov, Zh. [Nazarbayev University, Life Sciences Center, D. Kunayev str., Astana 010000 (Kazakhstan); Stepanenko, V. [Medical Radiological Research Center, Obninsk 249036 (Russian Federation); Abralina, Sh.; Sadvokasova, L. [Semey State Medical Academy, Semey 071400, Abay str. 103 (Kazakhstan); Zhumadilova, A. [Astana Medical University, 51a, Beibitshilik str., Astana 010000 (Kazakhstan); Toyoda, S. [Department of Applied Physics, Faculty of Science, Okayama University of Science, Okayama 700-0005 (Japan); Endo, S. [Department of Quantum Energy Applications, Graduated School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527 (Japan); Okamoto, T. [Department of Molecular Oral Medicine and Maxillofacial Surgery, Division of Frontier Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima 734-8553 (Japan); Hoshi, M. [Research Institute for Radiation Biology and Medicine, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553 (Japan)

    2011-09-15

    The method of electron spin resonance (ESR) dosimetry has been applied to human tooth enamel in order to obtain individual absorbed doses from the population of settlements within the vicinity of the central axis of the radioactive fallout trace from the contaminating nuclear surface test of 24, August 1956. Most of the settlements (Glubokoe, Tavriya, and Gagarino) are located near Ust-Kamenogorsk city, in Kazakhstan (about 400 km to the east from the epicenter of the explosion at the Semipalatinsk Nuclear Test Site (SNTS)). It was found that the excess doses obtained after the subtraction of natural background radiation ranged up to about 120 mGy for the residents of Ust-Kamenogorsk city, whose tooth enamel was formed before 1956. For the residents of Gagarino, excess doses do not exceed 47 mGy for all ages. For the residents of Tavriya, the maximum of excess dose was determined as 54 mGy and for the residents of Glubokoe, the maximum excess dose was about 83 mGy. For the population of the Shemonaikha settlements (about 70 km from the centerline of the radioactive fallout trace) the highest excess dose is 110 mGy. Also for this study, Znamenka village (about 130 km from the epicenter) was included. The Kokpekty settlement was chosen as a control and not subjected to any radioactive contamination and is located 400 km to the Southeast from SNTS.

  16. Neutron personnel dosimetry

    International Nuclear Information System (INIS)

    Griffith, R.V.

    1981-01-01

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments

  17. Thermoluminescent dosimetry in pediatric patients subjected to TAC cranium multi cutting studies

    International Nuclear Information System (INIS)

    Tabares V, M.J.; Azorin N, J.; Azorin V, J.C.

    2007-01-01

    Full text: In this work the doses to critical organs in pediatric patient subjected to studies of multi cutting skull tomography were determined. The study included patient smaller than 16. The used tomograph was a Siemens Somaton 16 plus multi cutting. The dosimetry one carries out with thermoluminescent dosemeters of LiF:Mg,Cu,P +Ptfe of national production. This dosemeters type was used due to it characteristics, such as low fading, equivalence with the tissue, easy handling and reading and independence of it answer with the radiation energy. The value of the absorbed doses in organs in the simple study results half of the obtained value in the contrasted study that which indicates that the CTDI vol is proportional to the dose to organ. In the case of the skull three-dimensional reconstruction tomography the CTDI vol was practically the same one that for simple tomography was practically; however, the doses to organs differed significantly. When comparing the TDI vol value of the three-dimensional reconstruction tomography with that of the contrasted tomography the obtained reason it was 1:2; however, the doses to organ didn't show the same relationship and the absorbed dose in the case of the thyroid gland was even bigger in the study of three-dimensional reconstruction. The value of the CTDI vol is a good indicator of the exposure factors selected for the tomographic exploration and it is useful for the determination of the effective dose, but it doesn't indicate the absorbed dose to organ. (Author)

  18. Biological dosimetry to determine the UV radiation climate inside the MIR station and its role in vitamin D biosynthesis

    Science.gov (United States)

    Rettberg, P.; Horneck, G.; Zittermann, A.; Heer, M.

    1998-11-01

    The vitamin D synthesis in the human skin, is absolutely dependent on UVB radiation. Natural UVB from sunlight is normally absent in the closed environment of a space station like MIR. Therefore it was necessary to investigate the UV radiation climate inside the station resulting from different lamps as well as from occasional solar irradiation behind a UV-transparent quartz window. Biofilms, biologically weighting and integrating UV dosimeters successfully applied on Earth (e.g. in Antarctica) and in space (D-2, Biopan I) were used to determine the biological effectiveness of the UV radiation climate at different locations in the space station. Biofilms were also used to determine the personal UV dose of an individual cosmonaut. These UV data were correlated with the concentration of vitamin D in the cosmonaut's blood and the dietary vitamin D intake. The results showed that the UV radiation climate inside the Mir station is not sufficient for an adequate supply of vitamin D, which should therefore be secured either by vitamin D supplementat and/or by the regular exposure to special UV lamps like those in sun-beds. The use of natural solar UV radiation through the quartz window for `sunbathing' is dangerous and should be avoided even for short exposure periods.

  19. Hematological dosimetry

    International Nuclear Information System (INIS)

    Fluery-Herard, A.

    1991-01-01

    The principles of hematological dosimetry after acute or protracted whole-body irradiation are reviewed. In both cases, over-exposure is never homogeneous and the clinical consequences, viz medullary aplasia, are directly associated with the mean absorbed dose and the seriousness and location of the overexposure. The main hematological data required to assess the seriousness of exposure are the following: repeated blood analysis, blood precursor cultures, as indicators of whole-body exposure; bone marrow puncture, medullary precursor cultures and medullary scintigraphy as indicators of the importance of a local over-exposure and capacity for spontaneous repair. These paraclinical investigations, which are essential for diagnosis and dosimetry, are also used for surveillance and for the main therapeutic issues [fr

  20. Computational dosimetry and risk assessment of radioinduced cancer: studies in mammary glands radiotherapy, radiopharmaceuticals and internal contamination

    International Nuclear Information System (INIS)

    Mendes, Bruno Melo

    2017-01-01

    The use of Ionizing radiation (IR) in medicine has increased considerably. The benefits generated by diagnostic and therapy techniques with IR are proven. Nevertheless, the risks arising from these uses should not be underestimated. Justification, a basic radiation protection, states that the benefits from exposures must outweigh detriment. The cancer induction is one of the detriment components. Thus, the study of the benefit/detriment ratio should take into account cancer incidence and mortality estimations resulting from a given diagnosis or therapy radiological technique. The risk of cancer induction depends on the absorbed doses in the irradiated organs and tissues. Thus, IR dosimetry is essential to evaluate the benefit/detriment ratio. The present work aims to perform computational dosimetric evaluations and estimations of cancer induction risk after ionizing radiation exposure. The investigated situations cover nuclear medicine, radiological contamination and radiotherapy fields. Computational dosimetry, with MCNPx Monte Carlo Code, was used as a tool to calculate the absorbed dose in the interest organs of the voxelized human models. The simulations were also used to obtain calibration factors and optimization of in vivo monitoring systems for internal contamination dosimetry. A breast radiotherapy (RT) standard protocol was simulated using the MCNPx code. The calculation of the radiation-induced cancer risk was adapted from the BEIR VII methodology for the Brazilian population. The absorbed doses used in the risk calculations were obtained through computational simulations of different exposure scenarios. During this work, two new computational phantoms, DM B RA and VW, were generated from tomographic images. Additional twelve voxelized phantoms, including the reference phantoms, RCP A M and RCP A F, and the child, baby, and fetus models were adapted to run on MCNP. Internal Dosimetry Protocols (IDP) for radiopharmaceuticals and for internal contamination

  1. Mammalian synthetic biology for studying the cell.

    Science.gov (United States)

    Mathur, Melina; Xiang, Joy S; Smolke, Christina D

    2017-01-02

    Synthetic biology is advancing the design of genetic devices that enable the study of cellular and molecular biology in mammalian cells. These genetic devices use diverse regulatory mechanisms to both examine cellular processes and achieve precise and dynamic control of cellular phenotype. Synthetic biology tools provide novel functionality to complement the examination of natural cell systems, including engineered molecules with specific activities and model systems that mimic complex regulatory processes. Continued development of quantitative standards and computational tools will expand capacities to probe cellular mechanisms with genetic devices to achieve a more comprehensive understanding of the cell. In this study, we review synthetic biology tools that are being applied to effectively investigate diverse cellular processes, regulatory networks, and multicellular interactions. We also discuss current challenges and future developments in the field that may transform the types of investigation possible in cell biology. © 2017 Mathur et al.

  2. Studies on 192Ir afterloading irradiation of the canine prostate with special consideration of thermoluminescent dosimetry

    International Nuclear Information System (INIS)

    Reuter, M.

    1986-01-01

    A method for high dose rate afterloading irradiation of the prostate with iridium 192 was developed. The isodoses of the urethra and rectum, which were measured by means of thermoluminescent dosimetry, showed deviations from the doses pre-calculated by computer (BRACHY), because this calculation is based on an anatomically ideal condition. (MBC) [de

  3. Study of some thermoluminescent phosphors for the dosimetry of ionizing radiations

    International Nuclear Information System (INIS)

    Jaafari, M.

    1983-01-01

    Thermoluminescence dosimetry techniques are reviewed and interactions radiation matter are recalled. The need for new phosphors is evidenced. Numerous phosphors are examined and calcium, strontium and barium sulfides are synthetized and deposited on glass supports. The thermoluminescence of the dosimeters obtained with these materials is analyzed [fr

  4. Potential of Hybrid Computational Phantoms for Retrospective Heart Dosimetry After Breast Radiation Therapy: A Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Moignier, Alexandra, E-mail: alexandra.moignier@irsn.fr [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Derreumaux, Sylvie; Broggio, David; Beurrier, Julien [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Chea, Michel; Boisserie, Gilbert [Groupe Hospitalier Pitie Salpetriere, Service de Radiotherapie, Paris (France); Franck, Didier; Aubert, Bernard [Institut de Radioprotection et de Surete Nucleaire, Fontenay-aux-Roses (France); Mazeron, Jean-Jacques [Groupe Hospitalier Pitie Salpetriere, Service de Radiotherapie, Paris (France)

    2013-02-01

    Purpose: Current retrospective cardiovascular dosimetry studies are based on a representative patient or simple mathematic phantoms. Here, a process of patient modeling was developed to personalize the anatomy of the thorax and to include a heart model with coronary arteries. Methods and Materials: The patient models were hybrid computational phantoms (HCPs) with an inserted detailed heart model. A computed tomography (CT) acquisition (pseudo-CT) was derived from HCP and imported into a treatment planning system where treatment conditions were reproduced. Six current patients were selected: 3 were modeled from their CT images (A patients) and the others were modelled from 2 orthogonal radiographs (B patients). The method performance and limitation were investigated by quantitative comparison between the initial CT and the pseudo-CT, namely, the morphology and the dose calculation were compared. For the B patients, a comparison with 2 kinds of representative patients was also conducted. Finally, dose assessment was focused on the whole coronary artery tree and the left anterior descending coronary. Results: When 3-dimensional anatomic information was available, the dose calculations performed on the initial CT and the pseudo-CT were in good agreement. For the B patients, comparison of doses derived from HCP and representative patients showed that the HCP doses were either better or equivalent. In the left breast radiation therapy context and for the studied cases, coronary mean doses were at least 5-fold higher than heart mean doses. Conclusions: For retrospective dose studies, it is suggested that HCP offers a better surrogate, in terms of dose accuracy, than representative patients. The use of a detailed heart model eliminates the problem of identifying the coronaries on the patient's CT.

  5. A Monte Carlo study of macroscopic and microscopic dose descriptors for kilovoltage cellular dosimetry

    Science.gov (United States)

    Oliver, P. A. K.; Thomson, Rowan M.

    2017-02-01

    This work investigates how doses to cellular targets depend on cell morphology, as well as relations between cellular doses and doses to bulk tissues and water. Multicellular models of five healthy and cancerous soft tissues are developed based on typical values of cell compartment sizes, elemental compositions and number densities found in the literature. Cells are modelled as two concentric spheres with nucleus and cytoplasm compartments. Monte Carlo simulations are used to calculate the absorbed dose to the nucleus and cytoplasm for incident photon energies of 20-370 keV, relevant for brachytherapy, diagnostic radiology, and out-of-field radiation in higher-energy external beam radiotherapy. Simulations involving cell clusters, single cells and single nuclear cavities are carried out for cell radii between 5 and 10~μ m, and nuclear radii between 2 and 9~μ m. Seven nucleus and cytoplasm elemental compositions representative of animal cells are considered. The presence of a cytoplasm, extracellular matrix and surrounding cells can affect the nuclear dose by up to 13 % . Differences in cell and nucleus size can affect dose to the nucleus (cytoplasm) of the central cell in a cluster of 13 cells by up to 13 % (8 % ). Furthermore, the results of this study demonstrate that neither water nor bulk tissue are reliable substitutes for subcellular targets for incident photon energies  <50 keV: nuclear (cytoplasm) doses differ from dose-to-medium by up to 32 % (18 % ), and from dose-to-water by up to 21 % (8 % ). The largest differences between dose descriptors are seen for the lowest incident photon energies; differences are less than 3 % for energies ≥slant 90 keV. The sensitivity of results with regard to the parameters of the microscopic tissue structure model and cell model geometry, and the importance of the nucleus and cytoplasm as targets for radiation-induced cell death emphasize the importance of accurate models for cellular dosimetry studies.

  6. SU-D-BRC-04: Development of Proton Tissue Equivalent Materials for Calibration and Dosimetry Studies

    Energy Technology Data Exchange (ETDEWEB)

    Olguin, E [Gainesville, FL (United States); Flampouri, S [University of Florida Proton Therapy Institute, Jacksonville, FL (United States); Lipnharski, I [University of Florida, Gainesville, FL (United States); Bolch, W [University Florida, Gainesville, FL (United States)

    2016-06-15

    Purpose: To develop new proton tissue equivalent materials (PTEM), urethane and fiberglass based, for proton therapy calibration and dosimetry studies. Existing tissue equivalent plastics are applicable only for x-rays because they focus on matching mass attenuation coefficients. This study aims to create new plastics that match mass stopping powers for proton therapy applications instead. Methods: New PTEMs were constructed using urethane and fiberglass resin materials for soft, fat, bone, and lung tissue. The stoichiometric analysis method was first used to determine the elemental composition of each unknown constituent. New initial formulae were then developed for each of the 4 PTEMs using the new elemental compositions and various additives. Samples of each plastic were then created and exposed to a well defined proton beam at the UF Health Proton Therapy Institute (UFHPTI) to validate its mass stopping power. Results: The stoichiometric analysis method revealed the elemental composition of the 3 components used in creating the PTEMs. These urethane and fiberglass based resins were combined with additives such as calcium carbonate, aluminum hydroxide, and phenolic micro spheres to achieve the desired mass stopping powers and densities. Validation at the UFHPTI revealed adjustments had to be made to the formulae, but the plastics eventually had the desired properties after a few iterations. The mass stopping power, density, and Hounsfield Unit of each of the 4 PTEMs were within acceptable tolerances. Conclusion: Four proton tissue equivalent plastics were developed: soft, fat, bone, and lung tissue. These plastics match each of the corresponding tissue’s mass stopping power, density, and Hounsfield Unit, meaning they are truly tissue equivalent for proton therapy applications. They can now be used to calibrate proton therapy treatment planning systems, improve range uncertainties, validate proton therapy Monte Carlo simulations, and assess in-field and out

  7. Amylase and blood cell-count hematological radiation-injury biomarkers in a rhesus monkey radiation model-use of multiparameter and integrated biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Blakely, W.F. [Uniformed Services University, Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)], E-mail: blakely@afrri.usuhs.mil; Ossetrova, N.I.; Manglapus, G.L.; Salter, C.A.; Levine, I.H.; Jackson, W.E.; Grace, M.B.; Prasanna, P.G.S.; Sandgren, D.J.; Ledney, G.D. [Uniformed Services University, Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603 (United States)

    2007-07-15

    Effective medical management of suspected radiation exposure incidents requires the recording of dynamic medical data (clinical signs and symptoms), biological assessments of radiation exposure, and physical dosimetry in order to provide diagnostic information to the treating physician and dose assessment for personnel radiation protection records. The need to rapidly assess radiation dose in mass-casualty and population-monitoring scenarios prompted an evaluation of suitable biomarkers that can provide early diagnostic information after exposure. We investigated the utility of serum amylase and hematological blood-cell count biomarkers to provide early assessment of severe radiation exposures in a non-human primate model (i.e., rhesus macaques; n=8) exposed to whole-body radiation of {sup 60}Co-gamma rays (6.5 Gy, 40cGymin{sup -1}). Serum amylase activity was significantly elevated (12.3{+-}3.27- and 2.6{+-}0.058-fold of day zero samples) at 1 and 2-days, respectively, after radiation. Lymphocyte cell counts decreased ({<=}15% of day zero samples) 1 and 2 days after radiation exposure. Neutrophil cell counts increased at day one by 1.9({+-}0.38)-fold compared with levels before irradiation. The ratios of neutrophil to lymphocyte cell counts increased by 13({+-}2.66)- and 4.23({+-}0.95)-fold at 1 and 2 days, respectively, after irradiation. These results demonstrate that increases in serum amylase activity along with decreases of lymphocyte counts, increases in neutrophil cell counts, and increases in the ratio of neutrophil to lymphocyte counts 1 day after irradiation can provide enhanced early triage discrimination of individuals with severe radiation exposure and injury. Use of the biodosimetry assessment tool (BAT) application is encouraged to permit dynamic recording of medical data in the management of a suspected radiological casualty.

  8. Dosimetry and shielding

    International Nuclear Information System (INIS)

    Farinelli, U.

    1977-01-01

    Today, reactor dosimetry and shielding have wide areas of overlap as concerns both problems and methods. Increased interchange of results and know-how would benefit both. The areas of common interest include calculational methods, sensitivity studies, theoretical and experimental benchmarks, cross sections and other nuclear data, multigroup libraries and procedures for their adjustment, experimental techniques and damage functions. This paper reviews the state-of-the-art and the latest development in each of these areas as far as shielding is concerned, and suggests a number of interactions that could be profitable for reactor dosimetry. Among them, re-evaluation of the potentialities of calculational methods (in view of the recent developments) in predicting radiation environments of interest; the application of sensitivity analysis to dosimetry problems; a common effort in the field of theoretical benchmarks; the use of the shielding one-material propagation experiments as reference spectra for detector cross sections; common standardization of the detector nuclear data used in both fields; the setting up of a common (or compatible) multigroup structure and library applicable to shielding, dosimetry and core physics; the exchange of information and experience in the fields of cross section errors, correlations and adjustment; and the intercomparison of experimental techniques

  9. Bio-dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Hadjidekova, V.; Kristova, R.; Stainova, A.; Deleva, S.; Popova, L.; Georgieva, D.

    2013-01-01

    Full text: Introduction: The impact of ionizing radiation in medical, occupational and accidental human exposure leads to adverse side effects such as increased mortality and carcinogenesis. Information about the level of absorbed dose is important for risk assessment and for implementation of appropriate therapy. In most cases of actual or suspected exposure to ionizing radiation biological dosimetry is the only way to assess the absorbed dose. What you will learn: In this work we discuss the methods for biodosimetry and technological developments in their application in various emergency situations. The application of biological dosimetry and assessment of the influence of external factors in the conduct of epidemiological studies of radiation effects in protracted low-dose ionizing radiation on humans is presented. Discussion: The results of cytogenetic analysis and biological evaluation of absorbed dose based on the analysis of dicentrics in peripheral blood lymphocytes of five people injured in a severe radiation accident in Bulgaria in 2011 are presented. The assessed individual doses of the injured persons are in the range of 1.2 to 5,2 Gy acute homogeneous irradiation and are in line with the estimates of international experts. Conclusion: An algorithm to conduct a biological assessment of the dose in limited radiation accidents and in large scale radiation accidents with large number irradiated or suspected for exposure persons is proposed

  10. Fast neutron spectrometry and dosimetry

    International Nuclear Information System (INIS)

    Blaize, S.; Ailloud, J.; Mariani, J.; Millot, J.P.

    1958-01-01

    We have studied fast neutron spectrometry and dosimetry through the recoil protons they produce in hydrogenated samples. In spectrometric, we used nuclear emulsions, in dosimetric, we used polyethylene coated with zinc sulphide and placed before a photomultiplier. (author) [fr

  11. A preliminary clinic dosimetry study for synchrotron radiation therapy at SSRF

    International Nuclear Information System (INIS)

    Li Zhaobin; Shi Zeliang; Zhang Qing; Wang Yong; Fu Shen

    2013-01-01

    Synchrotron radiation (SR) represents a unique and innovative anti-cancer treatment due to its unique physical features, including high flux density, and tunable and collimated radiation generation. The aim of this work is to assess the dosimetric properties of SR in Shanghai Synchrotron Radiation Facility (SSRF) for potential applications to clinical radiation oncology. The experiments were performed with 34 and 50 keV X-rays on the BL13W biomedical beamline of SSRF and the 6 MV X-rays from ARTISTE linac for the dosimetry study. The percentage depth dose (PDD) and the surface dose of the SR X-rays and the 6 MV photon beams were performed in solid water phantom with Gafchromic EBT3 films. All curves are normalized to the maximum calculated dose, The depth of full dose buildup is about 10 μm deeper for the monoenergetic X-ray beams of 34 and 50 keV. The beam transmits through the phantom, with a linear attenuation coefficient. The profile in the horizontal plane shows that the dose distribution is uniform within the facula, while the vertical profile shows a Gaussian distribution of the dose. The penumbra is less than 0.2 mm in the horizontal profile. Gafchromic EBT film may be a useful and convenient tool for dose measurement and quality control for the high space and density resolution. It is therefore important to gain a thorough understanding about the physical features of SR before this novel technology can be applied to clinical practice. (authors)

  12. Voice Use Among Music Theory Teachers: A Voice Dosimetry and Self-Assessment Study.

    Science.gov (United States)

    Schiller, Isabel S; Morsomme, Dominique; Remacle, Angélique

    2017-07-25

    This study aimed (1) to investigate music theory teachers' professional and extra-professional vocal loading and background noise exposure, (2) to determine the correlation between vocal loading and background noise, and (3) to determine the correlation between vocal loading and self-evaluation data. Using voice dosimetry, 13 music theory teachers were monitored for one workweek. The parameters analyzed were voice sound pressure level (SPL), fundamental frequency (F0), phonation time, vocal loading index (VLI), and noise SPL. Spearman correlation was used to correlate vocal loading parameters (voice SPL, F0, and phonation time) and noise SPL. Each day, the subjects self-assessed their voice using visual analog scales. VLI and self-evaluation data were correlated using Spearman correlation. Vocal loading parameters and noise SPL were significantly higher in the professional than in the extra-professional environment. Voice SPL, phonation time, and female subjects' F0 correlated positively with noise SPL. VLI correlated with self-assessed voice quality, vocal fatigue, and amount of singing and speaking voice produced. Teaching music theory is a profession with high vocal demands. More background noise is associated with increased vocal loading and may indirectly increase the risk for voice disorders. Correlations between VLI and self-assessments suggest that these teachers are well aware of their vocal demands and feel their effect on voice quality and vocal fatigue. Visual analog scales seem to represent a useful tool for subjective vocal loading assessment and associated symptoms in these professional voice users. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  13. Study and parameters survey for iodine-125 source dosimetry to be applied in brachytherapy

    International Nuclear Information System (INIS)

    Moura, Eduardo Santana de

    2011-01-01

    The use of brachytherapy technique with iodine-125 seeds to prostate cancer treatment has been used for decades with good clinical outcomes. To aim the Brazilian population necessities, IPEN-CNEN/SP developed the iodine-125 seed prototype with national technology. The objectives of this work are the development and the study of dosimetric procedures associates with the experimental acquisition of the useful parameters for the iodine-125 dosimetric characterization and to evaluate if the developed procedures, in this work, have the basic conditions to determinate the dosimetric analysis, that are fundamental for clinical procedures. The dosimeters selected for the analysis are the TLD-100 (LiF:Mg,Ti), initially these dosimeters were submitted for two selection steps to choose the dosimeters more reproducible for the dosimetric analysis. The two steps were the selection by the mass of the dosimeters and the reproducibility after four irradiation series in a Cobalt-60 irradiator (CTR-IPEN). Afterwards these steps, the dosimeters were irradiated in linear accelerator with 6 MV energy (Service of Radiotherapy - Hospital Israelita Albert Einstein) to yield the individual calibration factors to each dosimeter. After, the dosimeters were used to the irradiations with iodine-125 seed, 6711 model, (GE-Healthcare). The irradiations and others analysis with iodine-125 seeds yield the useful values for the determination of the parameters suggested by the AAPM (American Association of Physicists in Medicine): constant of dose rate, geometry function, dose radial function and anisotropy function. The results showed good agreement with the values published by the literature, for the same iodine- 125 model, this fact confirms that the realized parameters will be able to be used for the IPEN-CNEN iodine-125 seeds dosimetry and quality control. (author)

  14. Compartmental Modeling and Dosimetry of in Vivo Metabolic Studies of Leucine and Three Secretory Proteins in Humans Using Radioactive Tracers

    Science.gov (United States)

    Venkatakrishnan, Vaidehi

    1995-01-01

    Physical and mathematical models provide a systematic means of looking at biological systems. Radioactive tracer kinetic studies open a unique window to study complex tracee systems such as protein metabolism in humans. This research deals with compartmental modeling of tracer kinetic data on leucine and apolipoprotein metabolism obtained using an endogenous tritiated leucine tracer administered as a bolus, and application of compartmental modeling techniques for dosimetric evaluation of metabolic studies of radioiodinated apolipoproteins. Dr. Waldo R. Fisher, Department of Medicine, was the coordinating research supervisor and the work was carried out in his laboratory. A compartmental model for leucine kinetics in humans has been developed that emphasizes its recycling pathways which were examined over two weeks. This model builds on a previously published model of Cobelli et al, that analyzed leucine kinetic data up to only eight hours. The proposed model includes different routes for re-entry of leucine from protein breakdown into plasma accounting for proteins which turn over at different rates. This new model successfully incorporates published models of three secretory proteins: albumin, apoA-I, and VLDL apoB, in toto thus increasing its validity and utility. The published model of apoA-I, based on an exogenous radioiodinated tracer, was examined with data obtained using an endogenous leucine tracer using compartmental techniques. The analysis concludes that the major portion of apoA-I enters plasma by a fast pathway but the major fraction of apoA-I in plasma resides with a second slow pathway; further the study is suggestive of a precursor-product relationship between the two plasma apoA-I pools. The possible relevance of the latter suggestion to the aberrant kinetics of apoA-I in Tangier disease is discussed. The analysis of apoA-II data resulted in similar conclusions. A methodology for evaluating the dosimetry of radioiodinated apolipoproteins by

  15. In vivo dosimetry study of semi-conductors EPD-20 in total body irradiation technique; Etude de la dosimetrie in vivo par semi-conducteurs EPD-20 dans les conditions de l'irradiation corporelle totale

    Energy Technology Data Exchange (ETDEWEB)

    Besbes, M.; Kochbati, L.; Ben Abdennabi, A.; Abdessaied, S.; Salem, L.; Frikha, H.; Nasr Ben Ammar, C.; Hentati, D.; Gargouri, W.; Messai, T.; Benna, F.; Maalej, M. [Institut Salah-Azaiz, Service de radiotherapie oncologique, Tunis (Tunisia); Mahjoubi, H. [Institut superieur des technologies medicales de Tunis, Dept. de biophysique, Tunis (Tunisia); Farhat, L. [CHU Habib-Bourguiba, Service de radiotherapie oncologique, Sfax (Tunisia)

    2010-01-15

    Purpose: The objective of this work was the study of in vivo dosimetry performed in a series of 54 patients receiving total body irradiation (T.B.I.) at the Salah-Azaiz Institute of Tunis since 2004. In vivo dosimetry measurements were compared to analytically calculated doses from monitor units delivered. Patients and method: The irradiation was conducted by a linear accelerator (Clinac 1800, Varian, Palo Alto, USA) using nominal X-rays energies of 6 MV and 18 MV, depending on the thickness of the patient at the abdomen. The dose was measured by semi-conductors p-type E.P.D.-20. These diodes were calibrated in advance with an ionization chamber 'P.T.W. Farmer' type of 0.6 cm{sup 3} and were placed on the surface of plexiglas phantom in the same T.B.I. conditions. A study of dosimetric characteristics of semi-conductors E.P.D.-20 was carried out as a function of beam direction and temperature. Afterwards, we conducted a comparative analysis of doses measured using these detectors during irradiation to those calculated retrospectively from monitor units delivered to each patient conditioned by T.B.I.. Results: Experience showed that semi-conductors are sensitive to the angle of beam radiation (0-90 degrees) and the temperature (22-40 Celsius degrees). The maximum variation is respectively 5 and 7%, but in our irradiation conditions these correction factors are less than 1%. The analysis of the results of the in vivo dosimetry had shown that the ratio of the average measured doses and analytically calculated doses at the abdomen, mediastinum, right lung and head are 1.005, 1.007, 1.0135 and 1.008 with a standard deviation 'type A' respectively of 3.04, 2.37, 7.09 et 4.15%. Conclusion: In vivo dosimetry by semi-conductors is in perfect agreement with dosimetry by calculation. However, in vivo dosimetry using semiconductors is the only technique that can reflect the dose actually received instantly by the patient during T.B.I. given the many factors

  16. Dosimetry of fast neutrons

    International Nuclear Information System (INIS)

    Jahr, R.

    1975-03-01

    Following an explanation of the physical fundamentals of neutron dosimetry, the special needs in medicine and biology are gone into. It is shown that the dose equivalent used in radiation protection simplifies in an undue manner the complicated dependence of the biological effects. The reason for this is the fact that the RBE for heavy recoil nuclei, amongst others, depends on the energy and sort of particle, whereas it is approximately equal to one for electrons independent of the energy. It is thus necessary in the fields of biology and medicine to have additional information on energy spectra of the neutrons as well as of all charged secondary particles as a function of the position in the phantom. These are obtained partly by calculation and partly by special dosemeters. The accuracy achieved so far is 5%. (ORU/LH) [de

  17. A study of computational dosimetry and boron biodistribution for ex – situ lung BNCT at RA-3 Reactor

    International Nuclear Information System (INIS)

    Garabalino, M.A.; Trivillin, V. A.; Monti Hughes, A.; Pozzi, E.C.C.; Thorp, S.; Curotto, P; Miller, M.; Santa Cruz, G.A.; Saint Martin, G.; Schwint, A.E.; González, S.J.; Farías, R.O; Portu, A.; Ferraris, S.; Santa María, J.; Lange, F.; Bortolussi, S.; Altieri, S.

    2013-01-01

    Within the context of the preclinical ex-situ BNCT Project for the treatment of diffuse lung metastases, we performed boron biodistribution studies in a sheep model and computational dosimetry studies in human lung to evaluate the potential therapeutic efficacy of the proposed technique. Herein we report preliminary data that supports the use of the sheep model as an adequate human surrogate in terms of boron kinetics and uptake in clinically relevant tissues. Furthermore, the estimation of the potential therapeutic efficacy of the proposed treatment in humans, based on boron uptake values in the large animal model, yields promising tumor control probability values even in the most conservative scenario considered. (author)

  18. Using soils for accident dosimetry: a preliminary study using optically stimulated luminescence from quartz

    DEFF Research Database (Denmark)

    Fujita, Hiroki; Jain, Mayank; Murray, Andrew S.

    2011-01-01

    . The objective was to assess the potential of SAROSL dosimetry using soils for retrospective assessment of a radiation accident. Variation in dose with depth was also measured. The SAR data showed good reproducibility and dose recovery, and there was no evidence of fading of the quartz signal based on “delayed......” dose recovery experiments. The minimum detection limit (MDL) dose was about 0.1Gy. The dose dependence was measured using both the above SAR OSL protocol as well as a SAR thermoluminescence (TL, violet emission) protocol. The background doses were generally in the range of the MDL to several Gy......, and no clear trend in dose depth profile was observed. From these results, we conclude that SAR OSL dosimetry using natural quartz extracted from soil could be used to evaluate the dose of an accident....

  19. Reconstructive dosimetry of radiological accidents - a brazilian case study of industrial gammagraphy

    International Nuclear Information System (INIS)

    Silva, Francisco Cesar Augusto da; Hunt, John G.; Ramalho, Adriana; Pinto, Livia M.F. Amalfi

    2001-01-01

    In may 2000, an operator of industrial gammagraphy, during a work of maintenance of a cobalt source irradiator, suffered a radiological accident which caused serious consequences for its left hand. Specialists who work in the Group of Overexposure Analysis (GADE/IRD/CNEN), began the reconstructive dosimetry for estimate the radiation dose. The objective was to determine the real dose received by the operator and to make possible the medical evaluation and to prescribe the medical procedures for the involved victim's treatment. This work presents the reconstructive dosimetry done by theoretical, experimental and computation methods for determining the radiation doses of the operator. Related to the computation method a program was used for external dose calculation based on Monte Carlo's Method and a human body simulator composed by voxels. It is also showed values of the effective and equivalent doses that caused serious lesions in the operator's hand. (author)

  20. Reconstructive dosimetry of radiological accidents - study of a brazilian case of industrial gamma radiography

    International Nuclear Information System (INIS)

    Silva, Francisco Cesar Augusto da; Hunt, John G.; Ramalho, Adriana; Pinto, Livia M.F. Amalfi

    2002-01-01

    On May 2000, an industrial gamma radiography operator, during a maintenance work of a 60 Co irradiator, has suffered a radiological accident with severe consequences to the left hand. The experts of the High Doses Analysis Group (GADE/IRD/CNEN) initiated the reconstructive dosimetry for the radiation dose estimation, in order to determine the real dose received by the operator, and to help the medical evaluation for prescribing the medical procedures for treatment of the involved victim. This paper presents the reconstructive dosimetry performed through the determination of the radiation doses of the operator, based on theoretical, experimental and computational methods. For the computer methods, a program for the calculation of external doses were used, based on the Monte Carlo method, and a human body simulator composed by voxels. The values of effective and equivalent doses are also presented which has caused severe lesions on the operator hand

  1. Study of the response reduction of LiF:Mg, Ti dosimeter for high dose dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Torkzadeh, Falamarz [Nuclear Sciences and Technology Research Institute, Tehran (Iran, Islamic Republic of). Radiation Applications Research School; AEOI, Tehran (Iran, Islamic Republic of); Faripour, Heidar [Nuclear Sciences and Technology Research Institute, Tehran (Iran, Islamic Republic of). Laser and Optics Research School; AEOI, Tehran (Iran, Islamic Republic of); Mardashti, Forough; Manouchehri, Farhad [Nuclear Sciences and Technology Research Institute, Tehran (Iran, Islamic Republic of). Radiation Applications Research School

    2017-07-15

    A single crystal and 5 polycrystalline samples of LiF:Mg, Ti and their pellets were prepared and investigated so as to apply thermoluminescence high gamma dose dosimetry. Three zones of single crystal with dopant concentrations of 200 ppm of Mg and 20 ppm of Ti were also used to prepare the single crystal samples. For polycrystalline samples, dopant concentrations of 0.062 mol% Mg and Ti concentrations in the range of 0.016 and 0.046 mol% were used. All the samples were exposed to gamma doses of 1 kGy to 700 kGy and their response changes were determined by a gamma dose test of about 60 mGy. According to the results obtained, the use of response reduction by curve-fitting up to about 300 kGy can be performed reliably for high dose gamma dosimetry.

  2. Photonic engineering for biological study

    Science.gov (United States)

    Wu, Fei

    My dissertation focuses on designing and developing prototypes of optical tools in the laboratory that can facilitate practical medical therapies. More specifically, this dissertation examines two novel biophotonic techniques: (1) a frequency multiplexed confocal microscope with the potential to provide rational therapy of congestive heart failure (CHF), and (2) the "optical comb" with the potential to improve results of retina reattachment surgery and accelerate post surgical recovery. Next, I will discuss the background, design and initial experimental results of each study individually. Part I: The Frequency Multiplexed Confocal Microscope. To overcome the limitations of existing confocal microscope technology, this dissertation proposes a non-scanning, real-time, high resolution technique (a multi-point frequency multiplexed confocal microscope) to measure 3-D intracellular calcium ion concentration in a living cardiac myocyte. This method can be also applied to measure the intracellular sodium ion concentration, or other ions in which high quantum-yield fluorescent probes are available. The novelty of the proposed research lies in the introduction of carrier frequency multiplexing techniques which can differentiate fluorescence emitted at different spatial locations in cardiac myocyte by their modulated frequency. It therefore opens the possibility to visualize the transient dynamics of intracellular dynamics at multiple locations in cells simultaneously, which will shine a new light on our understanding of CHF. The procedure for frequency multiplexing proposed is described below. Multiple incident laser beams are focused onto different locations in an isolated rat cardiac myocyte with each beam modulated at a different carrier frequency. The fluorescence emission at each location therefore bears the same modulated frequency as the stimulation laser beam. Each fluorescence signal is sent to the photo multiplier tube (PMT) after being spatially filtered by a

  3. A feasibility study using radiochromic films for fast neutron 2D passive dosimetry

    International Nuclear Information System (INIS)

    Brady, Samuel L; Fallin, Brent; Gunasingha, Rathnayaka; Yoshizumi, Terry T; Howell, Calvin R; Crowell, Alexander S; Tonchev, Anton P; Dewhirst, Mark W

    2010-01-01

    The objective of this paper is threefold: (1) to establish sensitivity of XRQA and EBT radiochromic films to fast neutron exposure; (2) to develop a film response to radiation dose calibration curve and (3) to investigate a two-dimensional (2D) film dosimetry technique for use in establishing an experimental setup for a radiobiological irradiation of mice and to assess the dose to the mice in this setup. The films were exposed to a 10 MeV neutron beam via the 2 H(d,n) 3 He reaction. The XRQA film response was a factor of 1.39 greater than EBT film response to the 10 MeV neutron beam when exposed to a neutron dose of 165 cGy. A film response-to-soft tissue dose calibration function was established over a range of 0-10 Gy and had a goodness of fit of 0.9926 with the calibration data. The 2D film dosimetry technique estimated the neutron dose to the mice by measuring the dose using a mouse phantom and by placing a piece of film on the exterior of the experimental mouse setup. The film results were benchmarked using Monte Carlo and aluminum (Al) foil activation measurements. The radiochromic film, Monte Carlo and Al foil dose measurements were strongly correlated, and the film within the mouse phantom agreed to better than 7% of the externally mounted films. These results demonstrated the potential application of radiochromic films for passive 2D neutron dosimetry.

  4. Film dosimetry using a smart device camera: a feasibility study for point dose measurements.

    Science.gov (United States)

    Aland, Trent; Jhala, Ekta; Kairn, Tanya; Trapp, Jamie

    2017-10-03

    In this work, a methodology for using a smartphone camera, in conjunction with a light-tight box operating in reflective transmission mode, is investigated as a proof of concept for use as a film dosimetry system. An imaging system was designed to allow the camera of a smartphone to be used as a pseudo densitometer. Ten pieces of Gafchromic EBT3 film were irradiated to doses up to 16.89 Gy and used to evaluate the effects of reproducibility and orientation, as well as the ability to create an accurate dose response curve for the smartphone based dosimetry system, using all three colour channels. Results were compared to a flatbed scanner system. Overall uncertainty was found to be best for the red channel with an uncertainty of 2.4% identified for film irradiated to 2.5 Gy and digitised using the smartphone system. This proof of concept exercise showed that although uncertainties still exceed a flatbed scanner system, the smartphone system may be useful for providing point dose measurements in situations where conventional flatbed scanners (or other dosimetry systems) are unavailable or unaffordable.

  5. Film dosimetry using a smart device camera: a feasibility study for point dose measurements

    Science.gov (United States)

    Aland, Trent; Jhala, Ekta; Kairn, Tanya; Trapp, Jamie

    2017-10-01

    In this work, a methodology for using a smartphone camera, in conjunction with a light-tight box operating in reflective transmission mode, is investigated as a proof of concept for use as a film dosimetry system. An imaging system was designed to allow the camera of a smartphone to be used as a pseudo densitometer. Ten pieces of Gafchromic EBT3 film were irradiated to doses up to 16.89 Gy and used to evaluate the effects of reproducibility and orientation, as well as the ability to create an accurate dose response curve for the smartphone based dosimetry system, using all three colour channels. Results were compared to a flatbed scanner system. Overall uncertainty was found to be best for the red channel with an uncertainty of 2.4% identified for film irradiated to 2.5 Gy and digitised using the smartphone system. This proof of concept exercise showed that although uncertainties still exceed a flatbed scanner system, the smartphone system may be useful for providing point dose measurements in situations where conventional flatbed scanners (or other dosimetry systems) are unavailable or unaffordable.

  6. Topics in radiation dosimetry radiation dosimetry

    CERN Document Server

    1972-01-01

    Radiation Dosimetry, Supplement 1: Topics in Radiation Dosimetry covers instruments and techniques in dealing with special dosimetry problems. The book discusses thermoluminescence dosimetry in archeological dating; dosimetric applications of track etching; vacuum chambers of radiation measurement. The text also describes wall-less detectors in microdosimetry; dosimetry of low-energy X-rays; and the theory and general applicability of the gamma-ray theory of track effects to various systems. Dose equivalent determinations in neutron fields by means of moderator techniques; as well as developm

  7. Biological dosimetry of low doses (0.05 - 0.4 Gy) with micronucleus dicentrics and chromosome fragments

    International Nuclear Information System (INIS)

    Rodriguez, L.; Sanchez, E.; Linares, C.; Navlet, J.

    1997-01-01

    This study was carried out within the framework of the agreement between the National Nuclear Safety Council and the University of Alcala of Hernares and in co-operation with the Radiological Service and the Radiation Protection Unit of the Gregorio Maranon General Hospital of Madrid, where irradiations were performed. Blood samples were taken of 4 individuals irradiated with 6 doses of gamma rays between 0.05 Gy and 0.40 Gy, leaving an aliquot dose of 0 Gy. Cultures of lymphocytes for the study of dicentric chromosomes (DC) and chromosomal fragments (fr), stopping the first mitosis after postirradiation with Colcemid. A study of micronuclei (MN) in binuclear cells was also performed, interrupting the first cytokinesis after postirradiation with citocalasina B. After the corresponding studies with optical microscope, statistical analysis was made on the observed data on DC, fr and MN. We made a multiple linear regression analysis of the data of the 4 individuals. We obtained the average of the 4 individuals for each variable and dose and performed the variance analysis. According to our study, neither the DC nor the MN are valid dosemeters for lower doses up to 0.4 Gy. Nevertheless there are indications that the fragments are correlated with the dose to these levels. By increasing both the points of dose and the number of metaphases studied, we believe that a dose curve can be done that would allow to estimate with a reasonable degree of confidence the dose received by a sample irradiated

  8. Direct comparison of radiation dosimetry of six PET tracers using human whole-body imaging and murine biodistribution studies

    International Nuclear Information System (INIS)

    Sakata, Muneyuki; Oda, Keiichi; Toyohara, Jun; Ishii, Kenji; Nariai, Tadashi; Ishiwata, Kiichi

    2013-01-01

    We investigated the whole-body biodistributions and radiation dosimetry of five 11 C-labeled and one 18 F-labeled radiotracers in human subjects, and compared the results to those obtained from murine biodistribution studies. The radiotracers investigated were 11 C-SA4503, 11 C-MPDX, 11 C-TMSX, 11 C-CHIBA-1001, 11 C-4DST, and 18 F-FBPA. Dynamic whole-body positron emission tomography (PET) was performed in three human subjects after a single bolus injection of each radiotracer. Emission scans were collected in two-dimensional mode in five bed positions. Regions of interest were placed over organs identified in reconstructed PET images. The OLINDA program was used to estimate radiation doses from the number of disintegrations of these source organs. These results were compared with the predicted human radiation doses on the basis of biodistribution data obtained from mice by dissection. The ratios of estimated effective doses from the human-derived data to those from the mouse-derived data ranged from 0.86 to 1.88. The critical organs that received the highest absorbed doses in the human- and mouse-derived studies differed for two of the six radiotracers. The differences between the human- and mouse-derived dosimetry involved not only the species differences, including faster systemic circulation of mice and differences in the metabolism, but also measurement methodologies. Although the mouse-derived effective doses were roughly comparable to the human-derived doses in most cases, considerable differences were found for critical organ dose estimates and pharmacokinetics in certain cases. Whole-body imaging for investigation of radiation dosimetry is desirable for the initial clinical evaluation of new PET probes prior to their application in subsequent clinical investigations. (author)

  9. Internal dosimetry, past and future

    International Nuclear Information System (INIS)

    Johnson, J.R.

    1989-03-01

    This paper is a review of the progress in the dosimetry of internally deposited radionuclides (internal dosimetry) since World War II. Previous to that, only naturally occurring radionuclides were available and only a limited number of studies of biokinetics and dosimetry were done. The main radionuclides studied were 226 Ra, 228 Ra, and 224 Ra but natural uranium was also studied mainly because of its toxic effect as a heavy metal, and not because it was radioactive. The effects of 226 Ra in bone, mainly from the radium dial painters, also formed the only bases for the radiotoxicity of radionuclides in bone for many years, and it is still, along with 224 Ra, the main source of information on the effects of alpha emitters in bone. The publications of the International Commission on Radiological Protection that have an impact on internal dosimetry are used as mileposts for this review. These series of publications, more than any other, represent a broad consensus of opinion within the radiation protection community at the time of their publication, and have formed the bases for radiation protection practice throughout the world. This review is not meant to be exhaustive; it is meant to be a personnel view of the evolution of internal dosimetry, and to present the author's opinion of what the future directions in internal dosimetry will be. 39 refs., 2 tabs

  10. Neutron beam measurement dosimetry

    International Nuclear Information System (INIS)

    Amaro, C.R.

    1995-01-01

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR

  11. Study of radiation-induced paramagnetic centers in quartz and its possible use in radiation dosimetry

    International Nuclear Information System (INIS)

    Mansour, A.M.E.

    2008-01-01

    A new EPR dosimetry system has been developed based on the radiation-formed stable paramagnetic centers in quartz. The first part of the thesis includes the preparation of quartz rods (diameter = 3 mm, length = 10 mm) where quartz powder was mixed with molten mixture of paraffin wax and ethylene vinyl acetate copolymer (EVA). The binding-mixture EVA / paraffin do not present interference or noise in the EPR signal before or after irradiation to high doses. The quartz rods were prepared by different concentrations (5, 10, 20, 30 and 50 %). The rods (30 %) show good mechanical properties for safe and multi-use handling. The second part is concerned with studying the dosimetric characteristics of gamma irradiation sensitive rods where the radiation-formed stable free radicals (E-center, peroxy radical and non-bridging oxygen hole center) which analyzed by using electron paramagnetic resonance (EPR) spectrometer. Unirradiated rods have no EPR signals. The useful dose range of these rods was found to range from 0.1 to 80 kGy depending on concentration of quartz powder, indicating their suitability for low and high dose gamma radiation applications. Also it was found that quartz rod exhibits a linear dose response in the dose regions 0.1-2.34 and 2.34-26 kGy at optimum EPR parameters. The dosimeter response was assessed using the peak-to-peak amplitude of the first-derivatives EPR spectrum. Its EPR signal was found unchanged in shape with different doses and different concentrations. A signal line spectrum attributed to the E-center was observed after irradiation, and this radical is insensitive to temperature, light independence as well as it have a very low decay (4.768 % per year). The overall uncertainty for quartz rod dosimeters at 2σ (σ is standard deviation) was found to be 3.8436 %. The dosimetric parameters, e. g. dose response, effect of temperature during irradiation on response as well as pre- and post-irradiation stability at different storage conditions

  12. Modeling the impact of prostate edema on LDR brachytherapy: a Monte Carlo dosimetry study based on a 3D biphasic finite element biomechanical model

    Science.gov (United States)

    Mountris, K. A.; Bert, J.; Noailly, J.; Rodriguez Aguilera, A.; Valeri, A.; Pradier, O.; Schick, U.; Promayon, E.; Gonzalez Ballester, M. A.; Troccaz, J.; Visvikis, D.

    2017-03-01

    Prostate volume changes due to edema occurrence during transperineal permanent brachytherapy should be taken under consideration to ensure optimal dose delivery. Available edema models, based on prostate volume observations, face several limitations. Therefore, patient-specific models need to be developed to accurately account for the impact of edema. In this study we present a biomechanical model developed to reproduce edema resolution patterns documented in the literature. Using the biphasic mixture theory and finite element analysis, the proposed model takes into consideration the mechanical properties of the pubic area tissues in the evolution of prostate edema. The model’s computed deformations are incorporated in a Monte Carlo simulation to investigate their effect on post-operative dosimetry. The comparison of Day1 and Day30 dosimetry results demonstrates the capability of the proposed model for patient-specific dosimetry improvements, considering the edema dynamics. The proposed model shows excellent ability to reproduce previously described edema resolution patterns and was validated based on previous findings. According to our results, for a prostate volume increase of 10-20% the Day30 urethra D10 dose metric is higher by 4.2%-10.5% compared to the Day1 value. The introduction of the edema dynamics in Day30 dosimetry shows a significant global dose overestimation identified on the conventional static Day30 dosimetry. In conclusion, the proposed edema biomechanical model can improve the treatment planning of transperineal permanent brachytherapy accounting for post-implant dose alterations during the planning procedure.

  13. Pharmacokinetics and radiation dosimetry of 99mTc-3PRGD2 in healthy individuals: A pilot study

    International Nuclear Information System (INIS)

    Cheng Guanghui; Gao Shi; JI Tiefeng; Ma Qingjie; Wang Qing; Jia Bing; Chen Zuowei

    2012-01-01

    99m Tc-3PRGD 2 is a new SPECT radiotracer for several tumor imaging with high uptake where integrin α v β 3 is highly expressed. This pilot study was to assess the safety, biodistribution and radiation dosimetry of 99m Tc-3PRGD 2 in healthy volunteers. The 10 healthy male volunteers were injected with 99m Tc-3PRGD 2 (786.7±55.8 MBq, 19.1-24.2 mCi). Baseline measurements of vital signs, laboratory safety tests and 12-lead electrocardiogram were recorded before and after injection. Blood and urine samples were collected and radiation counts were obtained at various time points. Whole-body scans and ROIs of identified organs were used for visual analysis and estimating the radiation dosimetry. No adverse reactions were found during the study. 99m Tc-3PRGD 2 exhibited a rapid clearance from the blood with less than 45% of the initial dosage at 10 min after injection and gradual increasing radioactivity in urine with (52.9±6)% of original dose at 1440 min. The whole-body imaging showed high radioactive accumulation in bladder. And the highest 99m Tc-3PRGD 2 uptake was found in the kidneys (3.50×10 -2 mSv/MBq). The 99m Tc-3PRGD 2 exhibited good pharmacokinetic properties and little radiation burden. This study showed that 99m Tc-3PRGD 2 would be a safe and attractive SPECT agent in clinic applications. (authors)

  14. In vitro dissolution and radiation dosimetry of metal tritides

    International Nuclear Information System (INIS)

    Cheng, Y.S.; Dahl, A.R.; Jow, H.N.

    1993-01-01

    It has been completed to investigate the dissolution behavior of both titanium and erbium tritide particles in simulated biological fluids and in rats. Data from these studies will provide information to estimate the dosimetry of inhaled metal tritides. The dosimetric model can then be used as the technical basis for setting health protection limits, including the annual limit on intake and the derived air concentration for DOE facilities. (3 figs.)

  15. Studying cell biology in the skin.

    Science.gov (United States)

    Morrow, Angel; Lechler, Terry

    2015-11-15

    Advances in cell biology have often been driven by studies in diverse organisms and cell types. Although there are technical reasons for why different cell types are used, there are also important physiological reasons. For example, ultrastructural studies of vesicle transport were aided by the use of professional secretory cell types. The use of tissues/primary cells has the advantage not only of using cells that are adapted to the use of certain cell biological machinery, but also of highlighting the physiological roles of this machinery. Here we discuss advantages of the skin as a model system. We discuss both advances in cell biology that used the skin as a driving force and future prospects for use of the skin to understand basic cell biology. A unique combination of characteristics and tools makes the skin a useful in vivo model system for many cell biologists. © 2015 Morrow and Lechler. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  16. Cytometric approaches to biological dosimetry

    International Nuclear Information System (INIS)

    Burger, G.

    1983-01-01

    Automatic cytometric techniques for detecting chromosomal aberrations are being tested but will not be used in routine examinations for some time to come. Automatic micronuclei counts are more promising but not sufficiently sensitive in the low dose range ( [de

  17. Low-energy x-ray dosimetry studies (6 to 16 keV) at SSRL beamline 1-5

    International Nuclear Information System (INIS)

    Ipe, N.E.; Chatterji, S.; Fassograve, A.; Kase, K.R.; Seefred, R.; Bilski, P.; Soares, C.

    1997-01-01

    Synchrotron radiation facilities provide a unique opportunity for low-energy x-ray dosimetry studies because of the availability of monochromatic x-ray beams. Results of such studies performed at the Stanford Synchrotron Radiation Laboratory (SSRL) are described. Polish lithium fluoride thermoluminescent dosemeters (TLDs), MTS-N(LiF:Mg, Ti- 0.4 mm thick), MCP-N (LiF:Mg, Cu, P - 0.4 mm thick) were exposed free in air to monochromatic x-rays (6 - 16 keV). These exposures were monitored with an SSRL ionization chamber. The responses (counts/Gy) of MTS-N and MCP-N were generally found to increase with increasing energy. The response at 16 keV is about 3 and 4 times higher than the response at 6 keV for MTS-N and MCP-N, respectively. Irradiation at 6 keV indicates a fairly linear dose response for both type of TLDs over a dose range of 0.01 to 0.4 Gy. In addition there appears to be no significant difference in responses between irradiating the TLDs from the front and the back sides. The energy response of the PTW ionization chamber type 23342 relative to the SSRL ionization chamber is within ±4.5% between 6 and 16 keV. Both the TLDs and the PTW ionization chamber can also be used for beam dosimetry. copyright 1997 American Institute of Physics

  18. COMPARISON OF RESPONSE OF PASSIVE DOSIMETRY SYSTEMS IN SCANNING PROTON RADIOTHERAPY-A STUDY USING PAEDIATRIC ANTHROPOMORPHIC PHANTOMS.

    Science.gov (United States)

    Kneževic, Ž; Ambrozova, I; Domingo, C; De Saint-Hubert, M; Majer, M; Martínez-Rovira, I; Miljanic, S; Mojzeszek, N; Porwol, P; Ploc, O; Romero-Expósito, M; Stolarczyk, L; Trinkl, S; Harrison, R M; Olko, P

    2017-11-18

    Proton beam therapy has advantages in comparison to conventional photon radiotherapy due to the physical properties of proton beams (e.g. sharp distal fall off, adjustable range and modulation). In proton therapy, there is the possibility of sparing healthy tissue close to the target volume. This is especially important when tumours are located next to critical organs and while treating cancer in paediatric patients. On the other hand, the interactions of protons with matter result in the production of secondary radiation, mostly neutrons and gamma radiation, which deposit their energy at a distance from the target. The aim of this study was to compare the response of different passive dosimetry systems in mixed radiation field induced by proton pencil beam inside anthropomorphic phantoms representing 5 and 10 years old children. Doses were measured in different organs with thermoluminescent (MTS-7, MTS-6 and MCP-N), radiophotoluminescent (GD-352 M and GD-302M), bubble and poly-allyl-diglycol carbonate (PADC) track detectors. Results show that RPL detectors are the less sensitive for neutrons than LiF TLDs and can be applied for in-phantom dosimetry of gamma component. Neutron doses determined using track detectors, bubble detectors and pairs of MTS-7/MTS-6 are consistent within the uncertainty range. This is the first study dealing with measurements on child anthropomorphic phantoms irradiated by a pencil scanning beam technique. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Personal exposure to mobile phone frequencies and well-being in adults: a cross-sectional study based on dosimetry.

    Science.gov (United States)

    Thomas, Silke; Kühnlein, Anja; Heinrich, Sabine; Praml, Georg; Nowak, Dennis; von Kries, Rüdiger; Radon, Katja

    2008-09-01

    The use of mobile phone telecommunication has increased in recent years. In parallel, there is growing concern about possible adverse health effects of cellular phone networks. We used personal dosimetry to investigate the association between exposure to mobile phone frequencies and well-being in adults. A random population-based sample of 329 adults living in four different Bavarian towns was assembled for the study. Using a dosimeter (ESM-140 Maschek Electronics), we obtained an exposure profile over 24 h for three mobile phone frequency ranges (measurement interval 1 s, limit of determination 0.05 V/m). Exposure levels over waking hours were totalled and expressed as mean percentage of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) reference level. Each participant reported acute symptoms in a day-long diary. Data on five groups of chronic symptoms and potential confounders were assessed during an interview. The overall exposure to high-frequency electromagnetic fields was markedly below the ICNIRP reference level. We did not find any statistically significant association between the exposure and chronic symptoms or between the exposure and acute symptoms. Larger studies using mobile phone dosimetry are warranted to confirm these findings. Copyright 2008 Wiley-Liss, Inc.

  20. Study of the positioning of the films of the MLC by a Test of bands and your influence in the clinic dosimetry in IMRT

    International Nuclear Information System (INIS)

    Serrano Zabaleta, S.; Millan Cebrian, E.; Calvo Carrillo, S.; Alba Escorihuela, V.; Garcia Romero, A.; Ortega Pardina, P.; Canella Anoz, M.; Hernandez Vitoria, A.

    2015-01-01

    We performed a test of adjacent bands inspired by the proposed in AAPM Report No. 72, we provides a parameter characterizing the state of the MLC as to the actual position of its blades. This test has been validated by studying repeatability and reproducibility and has found the correlation between the parameter and creep detected by the ILD. Subsequently it has studied the impact of changes in the positioning of the blades on clinical dosimetry in IMRT patients, reconstructing the patient dose by Matrix Evolution team and Compass software, IBA Dosimetry. (Author)

  1. Radiation dosimetry

    International Nuclear Information System (INIS)

    Harper, M.W.; Thomas, B.; Conway, J.

    1977-01-01

    A dosemeter is described that is based on the TSCD principle (thermally stimulated current dosimetry). Basically this involves irradiating a responsive material and then heating it,whereby an electric current is produced. If the material is heated in an electric field the peak value of the thermally stimulated current or alternatively the total charge released by heating, can be related to the radiation dose received. The instrument described utilises a sheet coated with a thermoplastic polymer, such as a poly4-methylpent-l-ene. The polymer should have a softening point not lower than 150 0 C with an electrical resistivity of at least 10 16 chms/cm at 150 0 C. The polymer may also be PTFE. Heating should be in the range 150 0 C to 200 0 C and the electric field in the range 50 to 10,000V/mm. (U.K.)

  2. Organ dosimetry

    International Nuclear Information System (INIS)

    Kaul, Dean C.; Egbert, Stephen D.; Otis, Mark D.; Kuhn, Thomas; Kerr, George D.; Eckerman, Keith F.; Cristy, Mark; Ryman, Jeffrey C.; Tang, Jabo S.; Maruyama, Takashi

    1987-01-01

    This chapter describes the technical approach, complicating factors, and sensitivities and uncertainties of calculations of doses to the organs of the A-bomb survivors. It is the object of the effort so described to provide data that enables the dosimetry system to determine the fluence, kerma, absorbed dose, and similar quantities in 14 organs and the fetus, specified as being of radiobiological interest. This object was accomplished through the use of adjoint Monte Carlo computations, which use a number of random particle histories to determine the relationship of incident neutrons and gamma rays to those transported to a target organ. The system uses these histories to correlate externally-incident energy- and angle-differential fluences with the fluence spectrum (energy differential only) within the target organ. In order for the system to work in the most efficient manner possible, two levels of data were provided. The first level, represented by approximately 6,000 random adjoint-particle histories, enables the computation of the fluence spectrum with sufficient precision to provide statistically reliable (± 6 %) mean doses within any given organ. With this limited history inventory, the system can be run rapidly for all survivors. Mean organ dose and dose uncertainty are obtainable in this mode. The second mode of operation enables the system to produce a good approximation to fluence spectrum within any organ or to produce the dose in each of an array of organ subvolumes. To be statistically reliable, this level of detail requires far more random histories, approximately 40,000 per organ. Thus, operation of the dosimetry system in this mode (i.e., with this data set) is intended to be on an as-needed, organ-specific basis, since the system run time is eight times that in the mean dose mode. (author)

  3. Thermo-luminescent dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Reither, M; Schorn, B; Schneider, E

    1981-01-01

    The development of paediatric radiology which began in the late 195O's has been characterised by the need to limit the dose of ionising radiation to which the child is subjected. The aim has been to keep radiation exposure as low as possible by the introduction of suitable techniques and by the development of new methods. It is therefore surprising that studies in dosimetry in the paediaytric age range have only been carried out in recent years. One reason for this may have been the fact that a suitable technique of measurement was not available at the time. The introduction of solid state dosimetry based on thermo-luminescence, first into radiotherapy (1968) and subsequently into radiodiagnosis, has made it possible to abandon the previously widely used ionisation chamber. The purpose of the present paper is to indicate the suitability of this form of dose measurement for paediatric radiological purposes and to stimulate its application in this field.

  4. Spectroscopic, thermal and biological studies of coordination

    Indian Academy of Sciences (India)

    Spectroscopic, thermal and biological studies of coordination compounds of sulfasalazine drug: Mn(II), Hg(II), Cr(III), ZrO(II), VO(II) and Y(III) transition metal ... The thermal decomposition of the complexes as well as thermodynamic parameters ( *}, *, * and *) were estimated using Coats–Redfern and ...

  5. Study of biological effect of radiation

    International Nuclear Information System (INIS)

    Li Guisheng

    1992-01-01

    The some progress on the study of biological effect for protract exposure to low dose rate radiation is reported, and it is indicated that the potential risk of this exposure for the human health and the importance of the routine monitoring of radiation dose for various nuclear installations. The potential exposure to the low dose rate radiation would attract people's extra attention

  6. Correlation between prostate brachytherapy-related urethral stricture and peri-apical urethral dosimetry: A matched case–control study

    International Nuclear Information System (INIS)

    Earley, James J.; Abdelbaky, Ather M.; Cunningham, Melanie J.; Chadwick, Eliot; Langley, Stephen E.M.; Laing, Robert W.

    2012-01-01

    Background and purpose: Radiation dose to the bulbomembranous urethra has been shown to correlate with urethral stricture formation. This retrospective case–control study was designed to explore the relationship between dose to the apical/peri-apical regions of the urethra and development of brachytherapy (BXT)-related urethral stricture. Materials and methods: Cases were patients who developed urethral stricture after treatment with BXT as monotherapy and who had urethral dosimetry post-implant. Each case was matched with a control that had not developed urethral stricture. Dosimetry was compared between cases and controls. Results: Twenty-three cases were pair matched with 23 controls. There were no significant differences between the two groups in terms of age, presenting Prostate Specific Antigen (PSA), International Prostate Symptom Score (IPSS) or Gleason score. The dose delivered to the peri-apical and apical urethra was significantly higher for cases when compared with controls (peri-apical urethra: mean V 150 1.1 Vs 0.8 cc [p = 0.02]; apical urethra: mean dose 200 Vs 174 Gy [p = 0.01]). The distance from the prostate apex to isodose lines was also found to be significant in predicting stricture formation. Conclusion: There was evidence to suggest that the development of BXT-related stricture was associated with radiation dose at the apical and peri-apical urethra. Attention to the dose delivered to those areas may minimise the risk of developing such morbidity.

  7. Joint USNRC/EC consequence uncertainty study: The ingestion pathway, dosimetry and health effects expert judgment elicitations and results

    International Nuclear Information System (INIS)

    Harper, F.; Goossens, L.; Abbott, M.

    1996-01-01

    The US Nuclear Regulatory Commission (USNRC) and the European Commission (EC) have conducted a formal expert judgment elicitation jointly to systematically collect the quantitative information needed to perform consequence uncertainty analyses on a broad set of commercial nuclear power plants. Information from three sets of joint US/European expert panels was collected and processed. Information from the three sets of panels was collected in the following areas: in the phenomenological areas of atmospheric dispersion and deposition, in the areas of ingestion pathways and external dosimetry, and in the areas of health effects and internal dosimetry. This exercise has demonstrated that the uncertainty for particular issues as measured by the ratio of the 95th percentile to the 5th percentile can be extremely large (orders of magnitude), or rather small (factor of two). This information has already been used by many of the experts that were involved in this process in areas other than the consequence uncertainty field. The benefit to the field of radiological consequences is just beginning as the results of this study are published and made available to the consequence community

  8. Whole-body radiation dosimetry of 2-[18F]Fluoro-A-85380 in human PET imaging studies

    International Nuclear Information System (INIS)

    Obrzut, Sebastian L.; Koren, Andrei O.; Mandelkern, Mark A.; Brody, Arthur L.; Hoh, Carl K.; London, Edythe D.

    2005-01-01

    2-[ 18 F]Fluoro-A-85380 (2-[ 18 F]fluoro-3-(2(S)-azetidinylmethoxy)pyridine, 2-[ 18 F]FA) is a recently developed PET radioligand for noninvasive imaging of nicotinic acetylcholine receptors. Previous radiation absorbed dose estimates for 2-[ 18 F]FA were limited to evaluation of activity in only several critical organs. Here, we performed 2-[ 18 F]FA radiation dosimetry studies on two healthy human volunteers to obtain data for all important body organs. Intravenous injection of 2.9 MBq/kg of 2-[ 18 F]FA was followed by dynamic PET imaging. Regions of interest were placed over images of each organ to generate time-activity curves, from which we computed residence times. Radiation absorbed doses were calculated from the residence times using the MIRDOSE 3.0 program (version 3.0, ORISE, Oak Ridge, TN). The urinary bladder wall receives the highest radiation absorbed dose (0.153 mGy/MBq, 0.566 rad/mCi, for a 2.4-h voiding interval), followed by the liver (0.0496 mGy/MBq, 0.184 rad/mCi) and the kidneys (0.0470 mGy/MBq, 0.174 rad/mCi). The mean effective dose equivalent is estimated to be 0.0278 mSv/MBq (0.103 rem/mCi), indicating that radiation dosimetry associated with 2-[ 18 F]FA is within acceptable limits

  9. Dosimetry of internal emitting: principles and perspectives of the MIRD technology

    International Nuclear Information System (INIS)

    Ferro F, G.

    1999-01-01

    The development of the radiopharmaceutical technology have multiplied the number of radioisotopes with applications in therapeutical nuclear medicine so known as Directed radiotherapy. Assuming the radiation is capable to produce noxious effects in the biological systems, it is important to evaluate appropriately the risks and benefits of the administration of radioactive agents in the patient. The outstanding parameter in this evaluation is the absorbed dose, which is product of the radiation emitted by a radionuclide that is localized or distributed to the interior of the human body in study and whose its estimation helps to predict the efficacy of the treatment. The scheme generalized of MIRD, it was formulated from thirty years ago for evaluating the interior dosimetry at level of organs.The finality of this work is to show the basic principles of the MIRD methodology and its perspectives using innovator tools as the dosimetry for dynamic masses, in particular the personnel dosimetry for the organs of each patient, the dosimetry for the small structures inside the organs (sub organic dosimetry), the distributions of doses in three dimensions (S voxel), the dosimetry at cellular level and the quantitative acquisition of pharmaceutical data. (Author)

  10. Feasibility studies of using thin entrance window photodiodes for clinical electron beam dosimetry

    International Nuclear Information System (INIS)

    Nascimento, Cristina R.; Asfora, Viviane K.; Barros, Vinicius S.M.; Gonçalves, Josemary A.C.; Andrade, Lucas F.R.; Khoury, Helen J.; Bueno, Carmen C.

    2017-01-01

    The response of the commercial XRA-24 PIN photodiode (5.76 mm 2 active area) for clinical electron beam dosimetry covering the range of 8-12 MeV was investigated. Within this energy range, the charge generated in the diode's sensitive volume is linearly dependent on the absorbed dose up to 320 cGy. However, charge sensitivity coefficients evidenced that the dose response of the diode is slightly dependent on the electron beam energy. Indeed, the diode's energy dependence was within 8.5% for 8-12MeV electron beams. On the other hand, it was also observed an excellent repeatability of these results with a variation coefficient (VC) lower than 0.4%, which is within the 1% tolerance limit recommended by the AAPM TG-62. Furthermore, the agreement between the percentage depth dose profiles (PDD) gathered with the diode and the ionization chamber allowed achieving the electron beam quality within 1% of that obtained with the ionization chamber. Based on these results, the photodiode XRA-24 can be a reliable and inexpensive alternative for electron beams dosimetry. (author)

  11. Feasibility studies of using thin entrance window photodiodes for clinical electron beam dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Cristina R.; Asfora, Viviane K.; Barros, Vinicius S.M.; Gonçalves, Josemary A.C.; Andrade, Lucas F.R.; Khoury, Helen J.; Bueno, Carmen C., E-mail: vsmdbarros@gmail.com, E-mail: vikhoury@gmail.com, E-mail: hjkhoury@gmail.com, E-mail: cristinaramos@smartsat.com.br, E-mail: josemary@ipen.br, E-mail: ccbueno@ipen.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Instituto Federal de Educação, Ciência e Tecnologia de Pernambuco (IFPE), Recife-PE (Brazil). Departamento de Energia Nuclear; Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Santa Casa de Misericórdia de Itabuna, BA (Brazil)

    2017-11-01

    The response of the commercial XRA-24 PIN photodiode (5.76 mm{sup 2} active area) for clinical electron beam dosimetry covering the range of 8-12 MeV was investigated. Within this energy range, the charge generated in the diode's sensitive volume is linearly dependent on the absorbed dose up to 320 cGy. However, charge sensitivity coefficients evidenced that the dose response of the diode is slightly dependent on the electron beam energy. Indeed, the diode's energy dependence was within 8.5% for 8-12MeV electron beams. On the other hand, it was also observed an excellent repeatability of these results with a variation coefficient (VC) lower than 0.4%, which is within the 1% tolerance limit recommended by the AAPM TG-62. Furthermore, the agreement between the percentage depth dose profiles (PDD) gathered with the diode and the ionization chamber allowed achieving the electron beam quality within 1% of that obtained with the ionization chamber. Based on these results, the photodiode XRA-24 can be a reliable and inexpensive alternative for electron beams dosimetry. (author)

  12. Study of film dosimetry for radiotherapy with Gafchromic-RTQ plates

    International Nuclear Information System (INIS)

    Diaz Moreno, Rogelio Manuel; Lara Mas, Elier; Alfonso Laguardia, Rodolfo

    2009-01-01

    Film dosimetry allows quality control processes (CC) for advanced radiotherapy treatments, not achievable with other types of systems dosimetry, as is the determination of two-dimensional dose distribution provided with the planned treatment in selected planes. The aim of this work was to establish the possibilities of making this type of CC with the means available in the INOR. Plates were used radiochromic Gafchromic-RTQ, for quality control, which irradiated with Elekta Precise linear accelerator, according to the test planning developed in the treatment planning system Precise Plan. Were used as image processing software the Mephysto mc2, PTW, and routines scheduled at home on Matlab. Was prepared calibration curve Dose-response for these plates, and applied this calibration curve at other boards with known radiation dose to estimate proximity of the dose obtained through calibration. Other tests were performed to determine the conditions of repeatability and optimal parameters of the process. Conditions were established that are obtained more reliable , the which are lower than those reported Gafchromic-EBT plates, especially designed quantitative dosimetric purposes, but in certain ranges allow evaluate the of a plan with an acceptable degree of approximation. (author)

  13. Progress report, Biology and Health Physics Division, April 1 to June 30, 1975

    International Nuclear Information System (INIS)

    1975-09-01

    Interim results are reported on research at CRNL in health physics (dosimetry, instrumentation, monitoring); environmental research (limnology, radionuclide migration and kinetics); populaton research (tumor induction in mammals, human health records); and biology (radiobiology, genetic studies). (E.C.B.)

  14. Personnel neutron dosimetry

    International Nuclear Information System (INIS)

    Hankins, D.

    1982-04-01

    This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs

  15. Integration of new biological and physical retrospective dosimetry methods into EU emergency response plans - joint RENEB and EURADOS inter-laboratory comparisons.

    Science.gov (United States)

    Ainsbury, Elizabeth; Badie, Christophe; Barnard, Stephen; Manning, Grainne; Moquet, Jayne; Abend, Michael; Antunes, Ana Catarina; Barrios, Lleonard; Bassinet, Celine; Beinke, Christina; Bortolin, Emanuela; Bossin, Lily; Bricknell, Clare; Brzoska, Kamil; Buraczewska, Iwona; Castaño, Carlos Huertas; Čemusová, Zina; Christiansson, Maria; Cordero, Santiago Mateos; Cosler, Guillaume; Monaca, Sara Della; Desangles, François; Discher, Michael; Dominguez, Inmaculada; Doucha-Senf, Sven; Eakins, Jon; Fattibene, Paola; Filippi, Silvia; Frenzel, Monika; Georgieva, Dimka; Gregoire, Eric; Guogyte, Kamile; Hadjidekova, Valeria; Hadjiiska, Ljubomira; Hristova, Rositsa; Karakosta, Maria; Kis, Enikő; Kriehuber, Ralf; Lee, Jungil; Lloyd, David; Lumniczky, Katalin; Lyng, Fiona; Macaeva, Ellina; Majewski, Matthaeus; Vanda Martins, S; McKeever, Stephen W S; Meade, Aidan; Medipally, Dinesh; Meschini, Roberta; M'kacher, Radhia; Gil, Octávia Monteiro; Montero, Alegria; Moreno, Mercedes; Noditi, Mihaela; Oestreicher, Ursula; Oskamp, Dominik; Palitti, Fabrizio; Palma, Valentina; Pantelias, Gabriel; Pateux, Jerome; Patrono, Clarice; Pepe, Gaetano; Port, Matthias; Prieto, María Jesús; Quattrini, Maria Cristina; Quintens, Roel; Ricoul, Michelle; Roy, Laurence; Sabatier, Laure; Sebastià, Natividad; Sholom, Sergey; Sommer, Sylwester; Staynova, Albena; Strunz, Sonja; Terzoudi, Georgia; Testa, Antonella; Trompier, Francois; Valente, Marco; Hoey, Olivier Van; Veronese, Ivan; Wojcik, Andrzej; Woda, Clemens

    2017-01-01

    RENEB, 'Realising the European Network of Biodosimetry and Physical Retrospective Dosimetry,' is a network for research and emergency response mutual assistance in biodosimetry within the EU. Within this extremely active network, a number of new dosimetry methods have recently been proposed or developed. There is a requirement to test and/or validate these candidate techniques and inter-comparison exercises are a well-established method for such validation. The authors present details of inter-comparisons of four such new methods: dicentric chromosome analysis including telomere and centromere staining; the gene expression assay carried out in whole blood; Raman spectroscopy on blood lymphocytes, and detection of radiation-induced thermoluminescent signals in glass screens taken from mobile phones. In general the results show good agreement between the laboratories and methods within the expected levels of uncertainty, and thus demonstrate that there is a lot of potential for each of the candidate techniques. Further work is required before the new methods can be included within the suite of reliable dosimetry methods for use by RENEB partners and others in routine and emergency response scenarios.

  16. Personnel neutron dosimetry at Department of Energy facilities

    International Nuclear Information System (INIS)

    Brackenbush, L.W.; Endres, G.W.R.; Selby, J.M.; Vallario, E.J.

    1980-08-01

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered

  17. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  18. A series of Chinese mathematic phantom and study of its external radiation dosimetry character

    International Nuclear Information System (INIS)

    Geng Changran; Tang Xiaobin; Chen Da; Xie Qin

    2012-01-01

    On the discussion of effect on dosimetry by different races, different postures, and different weighting factors, a series of Chinese reference human including two genders and three postures were constructed in according with GBZ/T 200. With Monte-Carlo method, absorbed dose of each organ and effective dose of several energy and geometries were calculated. With different tissue weighting factors, difference can be found in lower energies with all geometries. Also different races and different postures can bring about the different doses with the shielding of human organs, especially for the lower energy. As a conclusion, corresponding situation should be considered in radiation protection, especially in radiology and complexity radiation field. (authors)

  19. Radiation-damage studies, irradiations and high-dose dosimetry for LHC detectors

    CERN Document Server

    Coninckx, F; León-Florián, E; Leutz, H; Schönbacher, Helmut; Sonderegger, P; Tavlet, Marc; Sopko, B; Henschel, H; Schmidt, H U; Boden, A; Bräunig, D; Wulf, F; Cramariuc, R; Ilie, D; Fattibene, P; Onori, S; Miljanic, S; Paic, G; Razen, B; Razem, D; Rendic, D; CERN. Geneva. Detector Research and Development Committee

    1991-01-01

    The proposal is divided into a main project and special projects. The main project consists of a service similar to the one given in the past to accelerator construction projects at CERN (ISR,SPS,LEP) on high-dose dosimetry, material irradiations, irradiations tests, standardization of test procedures and data compilations. Large experience in this field and numerous radiation damage test data of insulating and structural materials are available. The special projects cover three topics which are of specific interest for LHC detector physicists and engineers at CERN and in other high energy physics institutes, namely: Radiation effects in scintillators; Selection of radiation hard optical fibres for data transmission; and Selection and testing of radiation hard electronic components.

  20. Dosimetry study of East Kazakhstan residents by tooth enamel EPR spectroscopy

    Directory of Open Access Journals (Sweden)

    Zhumadilov Kassym

    2017-01-01

    Full Text Available The tooth enamel electron paramagnetic resonance (EPR dosimetry method was used to determine accidental doses of population of settlements in the vicinity of the Semipalatinsk Nuclear Test Site (SNTS, Kazakhstan. The influence of four explosions to the populations was included into this report. The distances between investigated settlements and Ground Zero (SNTS are in the range of 70-200 km from SNTS. Most of settlements (Dolon, Mostik, Bodene, Cheremushki, Kanonerka are located near the central axis of radioactive fallout trace from the most contaminating surface nuclear test, which was conducted in 29, August 1949. The other settlements located close to radioactive fallout trace result in a surface nuclear tests in 24, August 1956 (Ust-Kamenogorsk, Znamenka, Shemonaikha, Glubokoe, Tavriya, Gagarino, in 12 august 1953 (Sarzhal and in 7, August 1962 (Akzhar, Kurchatov, Begen, Semenovka, Buras, Grachi. Tooth samples were extracted according to medical recommendations in a course of ordinary dental treatment.

  1. Dosimetry study of East Kazakhstan residents by tooth enamel EPR spectroscopy

    Science.gov (United States)

    Zhumadilov, Kassym; Ivannikov, Alexander; Skvortsov, Valeriy; Stepanenko, Valeriy; Rakhypbekov, Tolebay; Hoshi, Masaharu

    2017-11-01

    The tooth enamel electron paramagnetic resonance (EPR) dosimetry method was used to determine accidental doses of population of settlements in the vicinity of the Semipalatinsk Nuclear Test Site (SNTS), Kazakhstan. The influence of four explosions to the populations was included into this report. The distances between investigated settlements and Ground Zero (SNTS) are in the range of 70-200 km from SNTS. Most of settlements (Dolon, Mostik, Bodene, Cheremushki, Kanonerka) are located near the central axis of radioactive fallout trace from the most contaminating surface nuclear test, which was conducted in 29, August 1949. The other settlements located close to radioactive fallout trace result in a surface nuclear tests in 24, August 1956 (Ust-Kamenogorsk, Znamenka, Shemonaikha, Glubokoe, Tavriya, Gagarino), in 12 august 1953 (Sarzhal) and in 7, August 1962 (Akzhar, Kurchatov, Begen, Semenovka, Buras, Grachi). Tooth samples were extracted according to medical recommendations in a course of ordinary dental treatment.

  2. Criticality accidents in solution (CRAC and SILENE programmes) and complementary studies of accidents; radiation dosimetry in human organism during the CRAC programme

    International Nuclear Information System (INIS)

    Barbry, M.; Dousset, M.

    C.R.A.C. (CRiticality occurring ACcidentally) programme is intended to study experimentally the development of a criticality accident as it could occur when handling solutions of fissile material as well as the radiological consequences of such an accident. The fissile matter solutions have been chosen (a) for practical considerations of use and (b) because the probability of an accident occurring seems greater with this type of environment, as the known accidents have shown. The programme is twofold: study of accident physics: form of the evolution (peak, plateau, oscillations, boil up of solutions) the most probable maximum power, minimal power, flux and radiation spectra emitted, freed energy, associated effects, radiolysis, constraints, etc., study of radiological consequences: area dosimetry, individual dosimetry, radiobiological studies, etc. Additional criticality Accident experiments have been and continue to be made on the SILENE reactor in the following principal domains: determination of the emission rate of gaseous fission products and aerosols, area dosimetry and health dosimetry in the presence of shields around the core to vary the neutron and gamma components of the radiation field. Improvement in the knowledge of certain particular aspects of the power excursion, radiolysis gas and pressure wave, experiments of the ''boiling'' type [fr

  3. Studies of P(VDF-HFP) copolymer applied to gamma dosimetry

    International Nuclear Information System (INIS)

    Liz, Otavio S.R.; Medeiros, Adriana S.

    2011-01-01

    When polymeric materials are irradiated by ionizing radiation, the effects are roughly divided into two types, degradation (chain scission) and chain link (crosslinking). These effects are normally identified by spectroscopic analysis in the UV-Vis and Infrared region. Recently, the intensities of optical absorption in the ultraviolet visible region (273 nm) due to radio-induction of conjugated C = C bonds in P(VDF-TrFE) copolymers have been successfully used for high dose gamma dosimetry, for doses ranging from 0.1 to 200 kGy. In this context, there is now an interest to conduct a similar systematic investigation of another fluorinated copolymer of PVDF, the poly(fluorovinylidene-co-hexafluoropropylene) [P(VDF-HFP)], not only in the UV-VIS region but also in the near and mid-infrared region. The copolymer used was obtained by randomly adding 10% molar of [CF2- CF-CF3] monomers in the [CH2-CF2]n main chain of PVDF homopolymer. Preliminary results have shown that the irradiated copolymer has characteristic absorption bands originated by irradiation in the FTIR spectrum. It was found that the 1852 cm -1 band, associated with C = O bonds, have a linear correlation with the absorbed dose for doses ranging from 10 to 750 kGy. The absorption band at 1729 cm -1 , associated to chain oxidation (C = O), has shown a similar behavior and can be used to measure doses from 100 to 1000 kGy. These results indicate that the FTIR absorption bands of gamma irradiated P (VDF-HFP) have great potential to be used in high dose dosimetry, without the addition of dyes. (author)

  4. Studies of P(VDF-HFP) copolymer applied to gamma dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Liz, Otavio S.R.; Medeiros, Adriana S. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear; Faria, Luiz O., E-mail: farialo@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    When polymeric materials are irradiated by ionizing radiation, the effects are roughly divided into two types, degradation (chain scission) and chain link (crosslinking). These effects are normally identified by spectroscopic analysis in the UV-Vis and Infrared region. Recently, the intensities of optical absorption in the ultraviolet visible region (273 nm) due to radio-induction of conjugated C = C bonds in P(VDF-TrFE) copolymers have been successfully used for high dose gamma dosimetry, for doses ranging from 0.1 to 200 kGy. In this context, there is now an interest to conduct a similar systematic investigation of another fluorinated copolymer of PVDF, the poly(fluorovinylidene-co-hexafluoropropylene) [P(VDF-HFP)], not only in the UV-VIS region but also in the near and mid-infrared region. The copolymer used was obtained by randomly adding 10% molar of [CF2- CF-CF3] monomers in the [CH2-CF2]n main chain of PVDF homopolymer. Preliminary results have shown that the irradiated copolymer has characteristic absorption bands originated by irradiation in the FTIR spectrum. It was found that the 1852 cm{sup -1} band, associated with C = O bonds, have a linear correlation with the absorbed dose for doses ranging from 10 to 750 kGy. The absorption band at 1729 cm{sup -1}, associated to chain oxidation (C = O), has shown a similar behavior and can be used to measure doses from 100 to 1000 kGy. These results indicate that the FTIR absorption bands of gamma irradiated P (VDF-HFP) have great potential to be used in high dose dosimetry, without the addition of dyes. (author)

  5. Primary Study about Intensity Signal of Electron Paramagnetic Resonance in vivo Tooth Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hoon; Gang, Seo Gon; Kim, Jeong In; Lee, Byung Il [KHNP Radiation Health Institute, Gyeongju (Korea, Republic of)

    2017-04-15

    The signal of Electron Paramagnetic Resonance(EPR) dosimetry system using human tooth has been well introduced as one of the efficient tool to evaluate radiation exposure. But, EPR dosimetry, even in the case of classical in vitro EPR system using tooth sample(measured molars), was regarded as having big signal fluctuation. One of reason for such difficulty in getting accurate intensity was the big effect of organic materials mixed in enamel part of teeth samples. They are mainly caused by the adaptation process of system itself to the movement of measured human subject. Generally, when we measured human teeth in vivo, five of six teeth spectrum were gathered and averaged for real evaluation. The these spectrum are measured under very different environment like angle of external magnet making magnetic filed with teeth(incisor). Random movement of these signals should be considered in different view point to understand and compare each EPR in vivo EPR spectrum. The peak to peak value of obtained five or six in vivo EPR system to get averaged value for final quantity of free radicals in hydroxy apatite crystal construction in enamel part of human teeth looks so randomly changed without regulation. But, in overall view, the EPR signal, especially at no irradiation level, is almost same for every measurement trial which is mainly composed of big noise and very small signal from real free radicals. The peak to peak value of obtained five or six in vivo EPR system to get averaged value for final quantity of free radicals in hydroxy apatite crystal construction in enamel part of human teeth looks so randomly changed without regulation.

  6. Primary Study about Intensity Signal of Electron Paramagnetic Resonance in vivo Tooth Dosimetry

    International Nuclear Information System (INIS)

    Choi, Hoon; Gang, Seo Gon; Kim, Jeong In; Lee, Byung Il

    2017-01-01

    The signal of Electron Paramagnetic Resonance(EPR) dosimetry system using human tooth has been well introduced as one of the efficient tool to evaluate radiation exposure. But, EPR dosimetry, even in the case of classical in vitro EPR system using tooth sample(measured molars), was regarded as having big signal fluctuation. One of reason for such difficulty in getting accurate intensity was the big effect of organic materials mixed in enamel part of teeth samples. They are mainly caused by the adaptation process of system itself to the movement of measured human subject. Generally, when we measured human teeth in vivo, five of six teeth spectrum were gathered and averaged for real evaluation. The these spectrum are measured under very different environment like angle of external magnet making magnetic filed with teeth(incisor). Random movement of these signals should be considered in different view point to understand and compare each EPR in vivo EPR spectrum. The peak to peak value of obtained five or six in vivo EPR system to get averaged value for final quantity of free radicals in hydroxy apatite crystal construction in enamel part of human teeth looks so randomly changed without regulation. But, in overall view, the EPR signal, especially at no irradiation level, is almost same for every measurement trial which is mainly composed of big noise and very small signal from real free radicals. The peak to peak value of obtained five or six in vivo EPR system to get averaged value for final quantity of free radicals in hydroxy apatite crystal construction in enamel part of human teeth looks so randomly changed without regulation.

  7. Study of constraints in using household NaCl salt for retrospective dosimetry

    Science.gov (United States)

    Elashmawy, M.

    2018-05-01

    Thermoluminescence (TL) characteristics of 5 different household NaCl salts and one analytical salt were determined to investigate the possible factors that affect the reliability of using household salt for retrospective dosimetry. Salts' TL sensitivities were found to be particle-size dependent and approached saturation at the largest size, whereas for salts that have the same particle size, the TL sensitivity depended on their origin. TL dependence on the particle size interprets significant variations in TL response reported in the literature for the same salt patch. The first TL readout indicated that all salts have similar glow curves with one distinctive peak. Typical second TL readout at two different doses showed a dramatic decrease in TL sensitivity associated with a significant change in the glow curve structure possessing two prominent peaks. Glow curve deconvolution (GCD) of the first TL readout for all salts yielded 6 individual glow peaks of first-order kinetics, whereas in GCD of second TL readouts, 5 individual glow peaks of second-order kinetics were obtained. Similarities in the glow curve structures of the first and second TL readouts suggest that additives such as KIO3 and MgCO3 have no effect on the TL process. Fading effect was evaluated for the salt of highest TL sensitivity, and it was found that the integral TL intensity decreased gradually and lost 40% of its initial value over 2 weeks, after which it remained constant. Results conclude that a household salt cannot be used for retrospective dosimetry without considering certain constraints such as the salt's origin and particle size. Furthermore, preparedness for radiological accidents and accurate dose reconstructions require that most of the commonly distributed household salt brands should be calibrated in advance and stored in a repository to be recalled in case of accidents.

  8. A study on the radiation and environment safety -Development of technology for biological dosimetry-

    International Nuclear Information System (INIS)

    Lee, Kang Suk; Kim, Kook Chan; Kim, In Kyoo; Kim, Jin Kyoo; Chun Kee Jung; Park, Hyo Kook; Kim, Sang Bok; Park Sun Yung

    1995-07-01

    Adult rats were treated a single, whole body exposure to a dose of 0.1, 0.5, 1.0, 2.0, 3.0 Gy. The animals were sacrificed 6, 24, 48, 72, 96 hours following exposure. The amount of serum acute phase proteins(haptoglobin, ceruloplasmin, C-reactive protein, alpha-1 antitrypsin, alpha-1 acid glycoprotein, transferrin) were measured by competitive ELISA. In the 0.1 Gy irradiated rats, serum haptoglobin, C-reactive protein and alpha-1 antitrypsin were 400% higher and serum transferrin was 50% lower as compared to controls, 96 hours after irradiation. Ceruloplasmin increased by 400%, 24 hours after irradiation, but 96 hours after irradiation, the concentration of this protein in rat returned to normal level. On the other hand, no changes were observed in the case of alpha-1 acid glycoprotein. In the group of the 3.0 Gy irradiated rats, transferrin increased by 200%, 96 hours after irradiation. These biochemical responses to radiation did not show dose-dependent relation, but the sensitivity of the indicators was high enough to detect absorbed dose of 0.1 Gy. The above results can be applied to the measurements of acute phase reactants in human serum for the assessment of exposure doses in radiation workers and patients under radiation therapy. 39 figs, 72 refs. (Author)

  9. Studies of the Electric Field Distribution in Biological Bodies - Experimental Dosimetry at Radiofrequencies

    Science.gov (United States)

    1985-12-05

    stability of these mixtures thus I extending their rosearch lifetime to several months. It has also been found that sagar can be used instead of...in the torso, the SAR t~osin cvpOnentii function along the direction of\\vde;e pwopagation. Theretfore. an exponential function \\%a% fitted to the dua

  10. A study on the radiation and environment safety -Development of technology for biological dosimetry-

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Suk; Kim, Kook Chan; Kim, In Kyoo; Kim, Jin Kyoo; Jung, Chun Kee; Park, Hyo Kook; Kim, Sang Bok; Yung, Park Sun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-07-01

    Adult rats were treated a single, whole body exposure to a dose of 0.1, 0.5, 1.0, 2.0, 3.0 Gy. The animals were sacrificed 6, 24, 48, 72, 96 hours following exposure. The amount of serum acute phase proteins(haptoglobin, ceruloplasmin, C-reactive protein, alpha-1 antitrypsin, alpha-1 acid glycoprotein, transferrin) were measured by competitive ELISA. In the 0.1 Gy irradiated rats, serum haptoglobin, C-reactive protein and alpha-1 antitrypsin were 400% higher and serum transferrin was 50% lower as compared to controls, 96 hours after irradiation. Ceruloplasmin increased by 400%, 24 hours after irradiation, but 96 hours after irradiation, the concentration of this protein in rat returned to normal level. On the other hand, no changes were observed in the case of alpha-1 acid glycoprotein. In the group of the 3.0 Gy irradiated rats, transferrin increased by 200%, 96 hours after irradiation. These biochemical responses to radiation did not show dose-dependent relation, but the sensitivity of the indicators was high enough to detect absorbed dose of 0.1 Gy. The above results can be applied to the measurements of acute phase reactants in human serum for the assessment of exposure doses in radiation workers and patients under radiation therapy. 39 figs, 72 refs. (Author).

  11. Test study of boron nitride as a new detector material for dosimetry in high-energy photon beams

    Science.gov (United States)

    Poppinga, D.; Halbur, J.; Lemmer, S.; Delfs, B.; Harder, D.; Looe, H. K.; Poppe, B.

    2017-09-01

    The aim of this test study is to check whether boron nitride (BN) might be applied as a detector material in high-energy photon-beam dosimetry. Boron nitride exists in various crystalline forms. Hexagonal boron nitride (h-BN) possesses high mobility of the electrons and holes as well as a high volume resistivity, so that ionizing radiation in the clinical range of the dose rate can be expected to produce a measurable electrical current at low background current. Due to the low atomic numbers of its constituents, its density (2.0 g cm-3) similar to silicon and its commercial availability, h-BN appears as possibly suitable for the dosimetry of ionizing radiation. Five h-BN plates were contacted to triaxial cables, and the detector current was measured in a solid-state ionization chamber circuit at an applied voltage of 50 V. Basic dosimetric properties such as formation by pre-irradiation, sensitivity, reproducibility, linearity and temporal resolution were measured with 6 MV photon irradiation. Depth dose curves at quadratic field sizes of 10 cm and 40 cm were measured and compared to ionization chamber measurements. After a pre-irradiation with 6 Gy, the devices show a stable current signal at a given dose rate. The current-voltage characteristic up to 400 V shows an increase in the collection efficiency with the voltage. The time-resolved detector current behavior during beam interrupts is comparable to diamond material, and the background current is negligible. The measured percentage depth dose curves at 10 cm  ×  10 cm field size agreed with the results of ionization chamber measurements within  ±2%. This is a first study of boron nitride as a detector material for high-energy photon radiation. By current measurements on solid ionization chambers made from boron nitride chips we could demonstrate that boron nitride is in principle suitable as a detector material for high-energy photon-beam dosimetry.

  12. Biological Studies of Posttraumatic Stress Disorder

    Science.gov (United States)

    Pitman, Roger K.; Rasmusson, Ann M.; Koenen, Karestan C.; Shin, Lisa M.; Orr, Scott P.; Gilbertson, Mark W.; Milad, Mohammed R.; Liberzon, Israel

    2016-01-01

    Preface Posttraumatic stress disorder (PTSD) is the only major mental disorder for which a cause is considered to be known, viz., an event that involves threat to the physical integrity of oneself or others and induces a response of intense fear, helplessness, or horror. Although PTSD is still largely regarded as a psychological phenomenon, over the past three decades the growth of the biological PTSD literature has been explosive, and thousands of references now exist. Ultimately, the impact of an environmental event, such as a psychological trauma, must be understood at organic, cellular, and molecular levels. The present review attempts to present the current state of this understanding, based upon psychophysiological, structural and functional neuroimaging, endocrinological, genetic, and molecular biological studies in humans and in animal models. PMID:23047775

  13. Feasibility study on the verification of actual beam delivery in a treatment room using EPID transit dosimetry

    International Nuclear Information System (INIS)

    Baek, Tae Seong; Chung, Eun Ji; Son, Jaeman; Yoon, Myonggeun

    2014-01-01

    The aim of this study is to evaluate the ability of transit dosimetry using commercial treatment planning system (TPS) and an electronic portal imaging device (EPID) with simple calibration method to verify the beam delivery based on detection of large errors in treatment room. Twenty four fields of intensity modulated radiotherapy (IMRT) plans were selected from four lung cancer patients and used in the irradiation of an anthropomorphic phantom. The proposed method was evaluated by comparing the calculated dose map from TPS and EPID measurement on the same plane using a gamma index method with a 3% dose and 3 mm distance-to-dose agreement tolerance limit. In a simulation using a homogeneous plastic water phantom, performed to verify the effectiveness of the proposed method, the average passing rate of the transit dose based on gamma index was high enough, averaging 94.2% when there was no error during beam delivery. The passing rate of the transit dose for 24 IMRT fields was lower with the anthropomorphic phantom, averaging 86.8% ± 3.8%, a reduction partially due to the inaccuracy of TPS calculations for inhomogeneity. Compared with the TPS, the absolute value of the transit dose at the beam center differed by −0.38% ± 2.1%. The simulation study indicated that the passing rate of the gamma index was significantly reduced, to less than 40%, when a wrong field was erroneously irradiated to patient in the treatment room. This feasibility study suggested that transit dosimetry based on the calculation with commercial TPS and EPID measurement with simple calibration can provide information about large errors for treatment beam delivery

  14. Chemical dosimetry principles in high dose dosimetry

    International Nuclear Information System (INIS)

    Mhatre, Sachin G.V.

    2016-01-01

    In radiation processing, activities of principal concern are process validation and process control. The objective of such formalized procedures is to establish documentary evidence that the irradiation process has achieved the desired results. The key element of such activities is inevitably a well characterized reliable dosimetry system that is traceable to recognized national and international dosimetry standards. Only such dosimetry systems can help establish the required documentary evidence. In addition, industrial radiation processing such as irradiation of foodstuffs and sterilization of health careproducts are both highly regulated, in particular with regard to dose. Besides, dosimetry is necessary for scaling up processes from the research level to the industrial level. Thus, accurate dosimetry is indispensable

  15. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Science.gov (United States)

    2010-01-01

    ...) Methods and equipment for analysis of biological materials; (3) A system of fixed nuclear accident... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... 10 Energy 4 2010-01-01 2010-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304...

  16. Dosimetry system 1986

    International Nuclear Information System (INIS)

    Woolson, William A.; Egbert, Stephen D.; Gritzner, Michael L.

    1987-01-01

    In May 1983, the authors proposed a dosimetry system for use by the Radiation Effects Research Foundation (RERF) that would incorporate the new findings and calculations of the joint United States - Japan working groups on the reassessment of A-bomb dosimetry. The proposed dosimetry system evolved from extensive discussions with RERF personnel, numerous meetings of the scientists from Japan and the United States involved in the dosimetry reassessment research, and requirements expressed by epidemiologists and radiobiologists on the various review panels. The dosimetry system proposed was based on considerations of the dosimetry requirements for the normal work of RERF and for future research in radiobiology, the computerized input data on A-bomb survivors available in the RERF data base, the level of detail, precision, and accuracy of various components of the dosimetric estimates, and the computer resources available at RERF in Hiroshima. These discussions and our own experience indicated that, in light of the expansion of computer and radiation technologies and the desire for more detail in the dosimetry, an entirely new approach to the dosimetry system was appropriate. This resulted in a complete replacement of the T65D system as distinguished from a simpler approach involving a renormalization of T65D parameters to reflect the new dosimetry. The proposed dosimetry system for RERF and the plan for implementation was accepted by the Department of Energy (DOE) Working Group on A-bomb Dosimetry chaired by Dr. R.F. Christy. The dosimetry system plan was also presented to the binational A-bomb dosimetry review groups for critical comment and was discussed at joint US-Japan workshop. A prototype dosimetry system incorporating preliminary dosimetry estimates and applicable to only a limited set of A-bomb survivors was installed on the RERF computer system in the fall of 1984. This system was successfully operated at RERF and provided an initial look at the impact of

  17. Applications of gel dosimetry

    International Nuclear Information System (INIS)

    Ibbott, Geoffrey S

    2004-01-01

    Gel dosimetry has been examined as a clinical dosimeter since the 1950s. During the last two decades, however, a rapid increase in the number of investigators has been seen, and the body of knowledge regarding gel dosimetry has expanded considerably. Gel dosimetry is still considered a research project, and the introduction of this tool into clinical use is proceeding slowly. This paper will review the characteristics of gel dosimetry that make it desirable for clinical use, the postulated and demonstrated applications of gel dosimetry, and some complications, set-backs, and failures that have contributed to the slow introduction into routine clinical use

  18. Dissolution rate and radiation dosimetry of metal tritides

    International Nuclear Information System (INIS)

    Jow, Hong-Nian; Cheng, Yung-Sung

    1993-01-01

    Metal tritides including titanium tritide (Ti 3 H x ) and erbium tritide (Er 3 H x ) have been used as components of neutron generators. These compounds can be released to the air as aerosols during fabrication, assembling and testing of components or in accidental or fugitive releases. As a result, workers could be exposed to these compounds by inhalation. A joint research project between SNL and ITRI (Inhalation Toxicology Research Institute) was initiated last fall to investigate the solubility of metal tritides, retention and translocation of inhaled particles and internal dosimetry of metal tritides. The current understanding of metal tritides and their radiation dosimetry for internal exposure are very limited. There is no provision in the ICRP-30 for tritium dosimetry in metal tritide form. However, a few papers in the literature suggested that the solubility of metal tritide could be low. The current radiation protection guidelines for metal tritide particles are based on the assumption that the biological behavior is similar to tritiated water which behaves like body fluid with a relative short biological half life (10 days). If the solubility of metal tritide is low, the biological half life of metal tritide particles and the dosimetry of inhalation exposure to these particles could be quite different from tritiated water. This would have major implications in current radiation protection guidelines for metal tritides Including annual limits of intakes and derived air concentrations. The preliminary results of metal tritide dissolution study at ITRI indicate that the solubility of titanium tritide is low. The outlines of the project, the preliminary results and future work will be discussed in presentation

  19. Study of the reliability of the TLDs reader in a Thermoluminescent dosimetry laboratory

    International Nuclear Information System (INIS)

    Silva F, J.C. da; Fonseca, H.G. da

    2006-01-01

    Acting from the beginning of the decade of 80 in a postal program called 'Dentistry Programs' the Institute of Radioprotection and Dosimetry (IRD) it makes an effort supported by the IAEA so that it can determine with security the reference levels for the diverse practices in radiodiagnostic, including the dentistry. The dentistry program that uses 4 TLDs of lithium fluorite (LiF 100) for evaluations of the doses and of the hemirreductor layer, until 1995 it had already verified close of 5529 X-ray equipment. This work accompanies the result of 3 main parameters (arbitrary reading, reference light and noise) of the reader Harshaw marks 5500, when it is used for routine readings of the TLDs that arrive in the dosimetry laboratory for the due ratings. Together with these TLDs 9 previously selected dosemeters of a certain dosemeters lot is placed with a percentage uncertainty of 3% (for 1 standard deviation). before them they were irradiated in an irradiator of Sr90/Y90 with a dose of approximately 5 mGy, they are treated thermally in an oven PTW it marks to 400 grades for 1 hour + 100 grades for 2 hours and 100 grades in 15 minutes after the irradiations. The referred methodology follows a procedure where they are distributed of 3 in 3 the chosen TLDs of the group of the 9, to the beginning, half and at the end among the total quantity of dosemeters read in the reading disk that it can read of a single time 50 dosemeters. Together with this 10 measurements of reference light and noise are made, data that are provided by the reader through the 'softer WinRem'. Finally the obtained results of reference light and noise, its are compared with the maker's recommendations. Already that of the arbitrary reading (average of the 9 TLDs and its uncertainties), it has revealed a reduction in the percentage uncertainty (2 deviations standard / average) with relationship to one of the first results already obtained through the methodology proposal. It has been, also, applied the

  20. Study of TSL and OSL properties of dental ceramics for accidental dosimetry applications

    International Nuclear Information System (INIS)

    Veronese, Ivan; Galli, Anna; Cantone, Marie Claire; Martini, Marco; Vernizzi, Fabrizio; Guzzi, Gianpaolo

    2010-01-01

    Interest is increasing in the development of new methodologies for accidental dose assessment, exploiting the luminescence and dosimetric properties of objects and materials which can be usually found directly on exposed subjects and/or in the contaminated area. In this work, several types of ceramics employed for dental prosthetics restoration, including both innovative materials used as sub-frames for the construction of the inner part of dental crowns (core), and conventional porcelains used for the fabrication of the external layer (veneer), were investigated with regard to their thermally and optically stimulated luminescence (TSL and OSL respectively) properties, in view of their potential application in accidental dosimetry. The sensitivity to ionizing radiation proved to strongly depend on the type and brand of ceramic, with minimum detectable dose ranging from few mGy up to several tens of mGy. A linear dose-response was observed for most of the samples. However, the luminescence signals were characterised by a significant fading, which has to be taken into account for a reliable accidental dose assessment after a radiation exposure event.

  1. Quality assurance study for dosimetry of Radiation Therapy equipment in Saudi Arabia

    International Nuclear Information System (INIS)

    Al-Mokhlef, Jazi M.; Nabaz, Noori

    2003-01-01

    International standards address the accuracy of dose delivery for radiation therapy machines as well as quality assurance and staffing levels for radiation therapy centers. We performed absolute calibrations of gamma ,X-ray and electron radiotherapy beams in all radiation therapy centers in Saudi Arabia. We also assessed quality assurance and staffing levels Dosimetric measurements were made with a portable dosimetry system, which consisted of a calibrated Farmer ionization chamber and an electrometer, small water phantom, barometer and thermometer. Differences between the measured and the expected output (c Gy/MU or c Gy/min) were found to be in the range of -11%+5%. About 17% of radiotherapy beams were not within the acceptable tolerance level (+/-3%). Quality assurance in some radiation centers was poor and staffing levels were inadequate. We found poor compliance with internationally accepted tolerance levels for dose calibration of radiotherapy beams at radiation therapy centers in Saudi Arabia. Analysis of medical physics staffing revealed severe discrepancies from those recommended by international guidelines .We recommend that radiation therapy centers be adequately staffed with qualified medical physics personnel and that periodic audit programs be required a governmental body. (author)

  2. Recent developments in neutron dosimetry and radiation damage calculations for fusion-materials studies

    International Nuclear Information System (INIS)

    Greenwood, L.R.

    1983-01-01

    This paper is intended as an overview of activities designed to characterize neutron irradiation facilities in terms of neutron flux and energy spectrum and to use these data to calculate atomic displacements, gas production, and transmutation during fusion materials irradiations. A new computerized data file, called DOSFILE, has recently been developed to record dosimetry and damage data from a wide variety of materials test facilities. At present data are included from 20 different irradiations at fast and mixed-spectrum reactors, T(d,n) 14 MeV neutron sources, Be(d,n) broad-spectrum sources, and spallation neutron sources. Each file entry includes activation data, adjusted neutron flux and spectral data, and calculated atomic displacements and gas production. Such data will be used by materials experimenters to determine the exposure of their samples during specific irradiations. This data base will play an important role in correlating property changes between different facilities and, eventually, in predicting materials performance in fusion reactors. All known uncertainties and covariances are listed for each data record and explicit references are given to nuclear decay data and cross sections

  3. Dosimetry of inhaled plutonium-239 dioxide in rodent lung: a morphometric study

    International Nuclear Information System (INIS)

    Rhoads, K.

    1979-06-01

    Morphometric analysis of rat and hamster lung did not demonstrate any extensive changes in lung composition or structure following inhalation exposure to 239 Pu0 2 at levels near that for maximum tumor yield in rats. The problem of dosimetry for this compound thus appears to be relatively uncomplicated by any major radiation-induced pathological alterations in the lung. Rat and hamster lung were found to be similar in structure and composition, with few significant differences which could be directly related to the different tumor responses. The distribution of 239 Pu0 2 particles was not uniform in all regions of the lung; thus estimation of the dose to specific tissues or regions within the lung requires a correction for this effect. Species differences were found for particle distribution in the subpleural region and major airways, and in the spatial association of particles, both of which may affect the tumor development process. These regions contain the principal target cells for tumor production and serve as foci for the origin of tumors. Different dose distributions within these regions may therefore explain, at least in part, the difference in tumor response to inhaled 239 Pu0 2 for rats and hamsters

  4. Medical radiation dosimetry theory of charged particle collision energy loss

    CERN Document Server

    McParland, Brian J

    2014-01-01

    Accurate radiation dosimetry is a requirement of radiation oncology, diagnostic radiology and nuclear medicine. It is necessary so as to satisfy the needs of patient safety, therapeutic and diagnostic optimisation, and retrospective epidemiological studies of the biological effects resulting from low absorbed doses of ionising radiation. The radiation absorbed dose received by the patient is the ultimate consequence of the transfer of kinetic energy through collisions between energetic charged particles and atoms of the tissue being traversed. Thus, the ability of the medical physicist to both measure and calculate accurately patient dosimetry demands a deep understanding of the physics of charged particle interactions with matter. Interestingly, the physics of charged particle energy loss has an almost exclusively theoretical basis, thus necessitating an advanced theoretical understanding of the subject in order to apply it appropriately to the clinical regime. ​ Each year, about one-third of the worl...

  5. Personal dosimetry calculations by means of radio pharmacokinetic and gamma graphic studies

    International Nuclear Information System (INIS)

    Arteaga de Murphy, C.; Ferro F, G.; Pedraza L, M.; Montoya M, C.E.

    2000-01-01

    The determination of the absorbed radiation dose is an essential factor to assess the risk to patient with a diagnostic study of nuclear medicine but over all it is indispensable for predicting the efficiency of individualized radio pharmacotherapy and weighting up the risk/benefit of the treatment. In studies for diagnostic or/and treatment of nuclear medicine generally the absorbed radiation dose is not determined for each patient since the methods for estimating it are laborious and include complex models such biological as mathematical, therefore is very important to have a relatively easy method. The obtained data with 99m Tc-Abp., a new radiopharmaceutical for osseous gammagraphy, were used with the purpose of exemplifying a practical method. The radio pharmacokinetic parameters were determined during 24 hours in 10 health voluntaries and serial gamma grams were taken during two hours to another voluntaries. The obtained data were used to estimate, with the MIRDOSE3 computer program, the absorbed radiation dose in an osseous dragging with 99m Tc-Abp. is low: 0.00472 m Gy/MBq to osseous marrow, mainly to the vertebral column and femur, and 0.00169 m Gy/ MBq to whole body. These data are lower than those informed in the medical literature for other bis phosphonates. (Author)

  6. Aqueous chemical dosimetry

    International Nuclear Information System (INIS)

    Matthews, R.W.

    1982-01-01

    Aqueous chemical dosimetry based on ceric and ferrous sulfate solutions and on a number of fluorescence-induced systems is reviewed. Particular attention is given to the factors affecting the response of these dosimeters to radiation and the corrections necessary for more accurate dosimetry under various irradiation conditions. The effect of cerous and ceric ion, oxygen, and sulfuric acid concentration on the ceric dosimeter is discussed together with the effects of temperature, energy of radiation, degraded energy spectra, and peroxysulfuric acids. Practical aspects of ceric/cerous dosimetry are given. Although ferrous sulfate solution is the most important and widely studied reference dosimeter, general agreement has not been reached on the ''best'' value for the molar extinction coefficient of ferric ions nor on the correction necessary to the G(Fe 3 - ) value for irradiations at temperatures significantly different from 25 0 C. New data are presented which indicate that the larger temperature coefficients given in the literature are more accurate. The ferrous sulfate system has been of great importance in establishing the primary radiolytic yields for 0.4 M sulfuric acid solution; it is shown how the failure to take into account the effect of oxygen and ferrous sulfate concentrations has led to erroneously high estimates of the zero solute concentration values in acid solutions. Some of the methods for extending the dose ranges measurable with ferrous sulfate-based solutions are reviewed. Substances which on irradiation give highly fluorescent products are among the most sensitive aqueous chemical dosimeters. These include benzoate and terephthalate solutions and the more recent coumarin and trimesate solutions. Advantages and disadvantages system are discussed. (author)

  7. TU-E-201-01: Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionists

    Energy Technology Data Exchange (ETDEWEB)

    Rehani, M. [Massachusetts General Hospital (United States)

    2015-06-15

    Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

  8. TU-E-201-01: Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionists

    International Nuclear Information System (INIS)

    Rehani, M.

    2015-01-01

    Madan M. Rehani, Massachusetts General Hospital and Harvard Medical School, Boston Methods for Eye Lens Dosimetry and Studies On Lens Opacities with Interventionalists Radiation induced cataract is a major threat among staff working in interventional suites. Nearly 16 million interventional procedures are performed annually in USA. Recent studies by the principal investigator’s group, primarily among interventional cardiologists, on behalf of the International Atomic Energy Agency, show posterior subcapsular (PSC) changes in the eye lens in 38–53% of main operators and 21–45% of support staff. These changes have potential to lead to cataract in future years, as per information from A-Bomb survivors. The International Commission on Radiological Protection has reduced dose limit for staff by a factor of 7.5 (from 150 mSv/y to 20 mSv/y). With increasing emphasis on radiation induced cataracts and reduction in threshold dose for eye lens, there is a need to implement strategies for estimating eye lens dose. Unfortunately eye lens dosimetry is at infancy when it comes to routine application. Various approaches are being tried namely direct measurement using active or passive dosimeters kept close to eyes, retrospective estimations and lastly correlating patient dose in interventional procedures with staff eye dose. The talk will review all approaches available and ongoing active research in this area, as well as data from surveys done in Europe on status of eye dose monitoring in interventional radiology and nuclear medicine. The talk will provide update on how good is Hp(10) against Hp(3), estimations from CTDI values, Monte Carlo based simulations and current status of eye lens dosimetry in USA and Europe. The cataract risk among patients is in CT examinations of the head. Since radiation induced cataract predominantly occurs in posterior sub-capsular (PSC) region and is thus distinguishable from age or drug related cataracts and is also preventable, actions on

  9. Spectroscopic study of biologically active glasses

    Science.gov (United States)

    Szumera, M.; Wacławska, I.; Mozgawa, W.; Sitarz, M.

    2005-06-01

    It is known that the chemical activity phenomenon is characteristic for some inorganic glasses and they are able to participate in biological processes of living organisms (plants, animals and human bodies). An example here is the selective removal of silicate-phosphate glass components under the influence of biological solutions, which has been applied in designing glasses acting as ecological fertilizers of controlled release rate of the nutrients for plants. The structure of model silicate-phosphate glasses containing the different amounts of the glass network formers, i.e. Ca 2+ and Mg 2+, as a binding components were studied. These elements besides other are indispensable of the normal growth of plants. In order to establish the function and position occupied by the particular components in the glass structure, the glasses were examined by FTIR spectroscopy (with spectra decomposition) and XRD methods. It has been found that the increasing amount of MgO in the structure of silicate-phosphate glasses causes the formation of domains the structure of which changes systematically from a structure of the cristobalite type to a structure corresponding to forsterite type. Whilst the increasing content of CaO in the structure of silicate-phosphate glasses causes the formation of domains the structure of which changes from a structure typical for cristobalite through one similar to the structure of calcium orthophosphate, to a structure corresponding to calcium silicates. The changing character of domains structure is the reason of different chemical activity of glasses.

  10. Proteomics in studying cancer stem cell biology.

    Science.gov (United States)

    Kranenburg, Onno; Emmink, Benjamin L; Knol, Jaco; van Houdt, Winan J; Rinkes, Inne H M Borel; Jimenez, Connie R

    2012-06-01

    Normal multipotent tissue stem cells (SCs) are the driving force behind tissue turnover and repair. The cancer stem cell theory holds that tumors also contain stem-like cells that drive tumor growth and metastasis formation. However, very little is known about the regulation of SC maintenance pathways in cancer and how these are affected by cancer-specific genetic alterations and by treatment. Proteomics is emerging as a powerful tool to identify the signaling complexes and pathways that control multi- and pluri-potency and SC differentiation. Here, the authors review the novel insights that these studies have provided and present a comprehensive strategy for the use of proteomics in studying cancer SC biology.

  11. Thermoluminescence albedo-neutron dosimetry

    International Nuclear Information System (INIS)

    Strand, T.; Storruste, A.

    1986-10-01

    The report discusses neutron detection with respect to dosimetry and compares different thermoluminescent dosimetry materials for neutron dosimetry. Construction and calibration of a thermoluminescence albedo neutron dosemeter, developed by the authors, is described

  12. Study of EPR/ESR Dosimetry in Fingernails as a Method for Assessing Dose of Victims of Radiological Accidents/Incidents

    Science.gov (United States)

    2008-06-17

    Dosimetry for Population in the Vicinity of the Most Contaminating Radioactive Fallout Trace After the First Nuclear Test in the Semipalatinsk Test Site ...collection, preparation, and measurements at an accident site can be met with techniques illustrated in this study. v “STUDY OF ELECTRON...the value of Bo at the predicted resonance site . At this site , the direction of magnetic moment of unpaired electrons and their spin state change

  13. Thermoluminescence in medical dosimetry

    International Nuclear Information System (INIS)

    Rivera, T.

    2011-10-01

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  14. Dosimetry for occupational exposure to cosmic radiation

    International Nuclear Information System (INIS)

    Bartlett, D.T.; McAulay, I.R.; Schrewe, U.J.

    1997-01-01

    Aircraft crew and frequent flyers are exposed to elevated levels of cosmic radiation of galactic and solar origin and secondary radiation produced in the atmosphere, aircraft structure, etc. This has been recognised for some time and estimates of the exposure of aircraft crew have been made previously and included in, for example, UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) publications. The recent increased interest has been brought about by several factors - the consideration that the relative biological effectiveness of the neutron component was being underestimated; the trend towards higher cruising altitudes for subsonic commercial aircraft and business jet aircraft; and most importantly, the recommendations of the International Commission on Radiological Protection (ICRP) in Publication 60, and the revision of the Euratom Basic Safety Standards Directive (BSS). In 1992, the European Dosimetry Group (EURADOS) established a Working Group to consider the exposure to cosmic radiation of aircraft crew, and the scientific and technical problems associated with radiation protection dosimetry for this occupational group. The Working Group was composed of fifteen scientists (plus a corresponding member) involved in this field of study and with knowledge of radiation measurement at aviation altitudes. This paper is based on the findings of this Working Group. (author)

  15. High level radiation dosimetry in biomedical research

    International Nuclear Information System (INIS)

    Inada, Tetsuo

    1979-01-01

    The physical and biological dosimetries relating to cancer therapy with radiation were taken up at the first place in the late intercomparison on high LET radiation therapy in Japan-US cancer research cooperative study. The biological dosimetry, the large dose in biomedical research, the high dose rate in biomedical research and the practical dosimeters for pulsed neutrons or protons are outlined with the main development history and the characteristics which were obtained in the relating experiments. The clinical neutron facilities in the US and Japan involved in the intercomparison are presented. Concerning the experimental results of dosimeters, the relation between the R.B.E. compared with Chiba (Cyclotron in National Institute of Radiological Sciences) and the energy of deuterons or protons used for neutron production, the survival curves of three cultured cell lines derived from human cancers, after the irradiation of 250 keV X-ray, cyclotron neutrons of about 13 MeV and Van de Graaff neutrons of about 2 MeV, the hatchability of dry Artemia eggs at the several depths in an absorber stack irradiated by 60 MeV proton beam of 40, 120 and 200 krad, the peak skin reaction of mouse legs observed at various sets of average and instantaneous dose rates, and the peak skin reaction versus three instantaneous dose rates at fixed average dose rate of 7,300 rad/min are shown. These actual data were evaluated numerically and in relation to the physical meaning from the viewpoint of the fundamental aspect of cancer therapy, comparing the Japanese measured values to the US data. The discussion record on the high dose rate effect of low LET particles on biological substances and others is added. (Nakai, Y.)

  16. SU-E-T-507: Internal Dosimetry in Nuclear Medicine Using GATE and XCAT Phantom: A Simulation Study

    Energy Technology Data Exchange (ETDEWEB)

    Fallahpoor, M; Abbasi, M [Tehran University of Medical Sciences, Vali-Asr Hospital, Tehran, Tehran (Iran, Islamic Republic of); Sen, A [University of Houston, Houston, TX (United States); Parach, A [Shahid Sadoughi University of Medical Sciences, Yazd, Yazd (Iran, Islamic Republic of); Kalantari, F [UT Southwestern Medical Center, Dallas, TX (United States)

    2015-06-15

    Purpose Monte Carlo simulations are routinely used for internal dosimetry studies. These studies are conducted with humanoid phantoms such as the XCAT phantom. In this abstract we present the absorbed doses for various pairs of source and target organs using three common radiotracers in nuclear medicine. Methods The GATE software package is used for the Monte Carlo simulations. A typical female XCAT phantom is used as the input. Three radiotracers 153Sm, 131I and 99mTc are studied. The Specific Absorbed Fraction (SAF) for gamma rays (99mTc, 153Sm and 131I) and Specific Fraction (SF) for beta particles (153Sm and 131I) are calculated for all 100 pairs of source target organs including brain, liver, lung, pancreas, kidney, adrenal, spleen, rib bone, bladder and ovaries. Results The source organs themselves gain the highest absorbed dose as compared to other organs. The dose is found to be inversely proportional to distance from the source organ. In SAF results of 153Sm, when the source organ is lung, the rib bone, gain 0.0730 (Kg-1) that is more than lung itself. Conclusion The absorbed dose for various organs was studied in terms of SAF and SF. Such studies hold importance for future therapeutic procedures and optimization of induced radiotracer.

  17. Structural Studies of Biological Solids Using NMR

    Science.gov (United States)

    Ramamoorthy, Ayyalusamy

    2011-03-01

    High-resolution structure and dynamics of biological molecules are important in understanding their function. While studies have been successful in solving the structures of water-soluble biomolecules, it has been proven difficult to determine the structures of membrane proteins and fibril systems. Recent studies have shown that solid-state NMR is a promising technique and could be highly valuable in studying such non-crystalline and non-soluble biosystems. I will present strategies to study the structures of such challenging systems and also about the applications of solid-state NMR to study the modes of membrane-peptide interactions for a better assessment of the prospects of antimicrobial peptides as substitutes to antibiotics in the control of human disease. Our studies on the mechanism of membrane disruption by LL-37 (a human antimicrobial peptide), analogs of the naturally occurring antimicrobial peptide magainin2 extracted from the skin of the African frog Xenopus Laevis, and pardaxin will be presented. Solid-state NMR experiments were used to determine the secondary structure, dynamics and topology of these peptides in lipid bilayers. Similarities and difference in the cell-lysing mechanism, and their dependence on the membrane composition, of these peptides will be discussed. Atomic-level resolution NMR structures of amyloidogenic proteins revealing the misfolding pathway and early intermediates that play key roles in amyloid toxicity will also be presented.

  18. Thin film tritium dosimetry

    Science.gov (United States)

    Moran, Paul R.

    1976-01-01

    The present invention provides a method for tritium dosimetry. A dosimeter comprising a thin film of a material having relatively sensitive RITAC-RITAP dosimetry properties is exposed to radiation from tritium, and after the dosimeter has been removed from the source of the radiation, the low energy electron dose deposited in the thin film is determined by radiation-induced, thermally-activated polarization dosimetry techniques.

  19. The applications of microdosimetry in radiation biology study

    International Nuclear Information System (INIS)

    Kim, Eunhee

    2002-01-01

    To understand the mechanisms by which the ionizing radiation causes these damages, the spatial patterns of interaction and energy deposition by radiations should be explained in cellular level. All the descriptions of the physical process of radiation interaction and energy transfer in cellular or microscopic scale constitute the field of microdosimetry. The underlying motivations of microdosimetry study range from the efficient control of the radiation protection measures to the improvement of the diagnostic and therapeutic effectiveness in medical applications of radiation. The major quantity in the conventional radiation dosimetry or the macroscopic dosimetry is the 'absorbed dose' defined as the mean value of the possible energy depositions per unit mass of the target. With the microscopic targets such as cells and subcellular organelles, the average quantity can not represent the radiation actions on the targets any more because of the inhomogeneous and stochastic nature in radiation interaction with matter. The essence of microdosimetry is to study the fluctuation of energy deposition in a microscopic volume and its deviation from the mean value attributed to the inherent randomness of radiation interactions with matter

  20. Biological Indicators in Studies of Earthquake Precursors

    Science.gov (United States)

    Sidorin, A. Ya.; Deshcherevskii, A. V.

    2012-04-01

    Time series of data on variations in the electric activity (EA) of four species of weakly electric fish Gnathonemus leopoldianus and moving activity (MA) of two cat-fishes Hoplosternum thoracatum and two groups of Columbian cockroaches Blaberus craniifer were analyzed. The observations were carried out in the Garm region of Tajikistan within the frameworks of the experiments aimed at searching for earthquake precursors. An automatic recording system continuously recorded EA and DA over a period of several years. Hourly means EA and MA values were processed. Approximately 100 different parameters were calculated on the basis of six initial EA and MA time series, which characterize different variations in the EA and DA structure: amplitude of the signal and fluctuations of activity, parameters of diurnal rhythms, correlated changes in the activity of various biological indicators, and others. A detailed analysis of the statistical structure of the total array of parametric time series obtained in the experiment showed that the behavior of all animals shows a strong temporal variability. All calculated parameters are unstable and subject to frequent changes. A comparison of the data obtained with seismicity allow us to make the following conclusions: (1) The structure of variations in the studied parameters is represented by flicker noise or even a more complex process with permanent changes in its characteristics. Significant statistics are required to prove the cause-and-effect relationship of the specific features of such time series with seismicity. (2) The calculation of the reconstruction statistics in the EA and MA series structure demonstrated an increase in their frequency in the last hours or a few days before the earthquake if the hypocenter distance is comparable to the source size. Sufficiently dramatic anomalies in the behavior of catfishes and cockroaches (changes in the amplitude of activity variation, distortions of diurnal rhythms, increase in the

  1. Dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Musilek, L.; Seda, J.; Trousil, J.

    1992-01-01

    The publication deals with a major field of ionizing radiation dosimetry, viz., integrating dosimetric methods, which are the basic means of operative dose determination. It is divided into the following sections: physical and chemical effects of ionizing radiation; integrating dosimetric methods for low radiation doses (film dosimetry, nuclear emulsions, thermoluminescence, radiophotoluminescence, solid-state track detectors, integrating ionization dosemeters); dosimetry of high ionizing radiation doses (chemical dosimetric methods, dosemeters based on the coloring effect, activation detectors); additional methods applicable to integrating dosimetry (exoelectron emission, electron spin resonance, lyoluminescence, etc.); and calibration techniques for dosimetric instrumentation. (Z.S.). 422 refs

  2. Considerations on the miniaturization of detectors for in vivo dosimetry in radiotherapy: A Monte Carlo study

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Micaela; Testa, Etienne [Université de Lyon, F-69622, Lyon (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon (France); Beuve, Michael, E-mail: m.beuve@ipnl.in2p3.fr [Université de Lyon, F-69622, Lyon (France); CNRS/IN2P3, Institut de Physique Nucléaire de Lyon (France); Balosso, Jacques; Chaikh, Abdulhamid [Department of Radiation Oncology and Medical Physics, Grenoble Alpes University Hospital (CHUGA), Grenoble (France)

    2017-05-15

    The evolution of technology in radiotherapy nowadays allows us to deliver much higher doses to the target volumes, thanks to better absorbed dose distribution accuracy and conformation, while better sparing healthy tissues. In photon radiotherapy, higher precision usually entails employing small and moving beams. This emphasizes the role of in vivo dosimetry, which assesses internal absorbed dose rather than entrance dose. This, along with advances in materials science, results in a tendency towards the miniaturization of dosimeters. However, the stochastic nature of the radiation-matter interaction takes on greater importance at smaller scales, resulting in fluctuations in energy deposition whose effect may not be negligible. Miniaturization needs to take this into account. We estimated such fluctuations by Monte Carlo simulations considering energy deposition in cylindrical volumes of different sizes and for several absorbed dose values. We not only present and discuss the probability distributions of absorbed doses for a large range of target sizes (0.1–10 μm) and clinically relevant doses (0.1–10 Gy), but also derive an estimation of the risk of measuring an absorbed dose with a value outside a given interval of tolerance (3, 5 and 10%) around the expected dose. The distributions presented features consistent with the theory of microdosimetry. Those for dosimeter sizes smaller than 0.3 μm showed a very high dispersion in specific energy, while those for 10 μm dosimeters tended to become Gaussian and narrower with increasing absorbed dose. The probability of measuring an absorbed dose outside the defined interval of tolerance is close to 100% for the smallest size, regardless of the dose and the interval width considered. It decreases with increasing dose, dosimeter size and width of the interval of tolerance. The best results were obtained with 10 μm dosimeters, for which the probability of doses outside the tolerance range is always zero for absorbed

  3. Optimization of the preparation method of LiF: Mg, Cu, P and study of its thermoluminescent properties to be used in ionizing radiation dosimetry

    International Nuclear Information System (INIS)

    Gonzalez M, P.R.

    1995-01-01

    In this thesis the preparation and dosimetric properties of the thermoluminescence phosphor LiF doped with magnesium, copper and phosphorus are studied. In chapter 1 luminescence phenomenon in solids is described, emphasizing the importance of thermally stimulated luminescence known as thermoluminescence (TL) as well as its application in ionizing radiation dosimetry. The models used to determine the kinetics parameters in the TL phenomenon are described in chapter 2. In chapter 3, the dosimetric characteristics of a TL materials and its requirements for dosimetry are analyzed. The preparation method of LiF: Mg, Cu, P is presented in chapter 4 studying its general characteristics for dosimetry. The concentrations of dopants, glow curve structure, TL response to gamma, beta and alpha exposures are studied along with those of LiF: Mg, Cu, P prepared for other authors and with those of LiF: Mg, Ti (TLD-100). The kinetic parameters of the phosphor were determined by the deconvolution method. Pellets of this new phosphor powder were made by pressing it at room temperature and sintering in inert atmosphere at 700 Centigrade degrees. Dosimetric characteristics of these pellets were also studied. Chapter 5 presents the results and conclusions of this study. The new dosimeter exhibited three peaks in its glow curve at 140, 180 and 220 Centigrade degrees respectively. Its TL response to gamma radiation was linear from 43.5 μ Gy to 100 Gy. This dosimeter is reusable and stable without significant loss of sensitivity. Its sensitivity was about 30 times higher than that of TLD-100. Fading of this dosimeter was negligible at room temperature as well as at body temperature (37 Centigrade degrees), and 65% at 60 Centigrade degrees. In conclusion, this dosimeter meets all the requirements of the ANSI standard. These and other characteristics render this dosimeter useful in diverse applications of radiation dosimetry. (Author)

  4. Studies on the Promotion of Biological Application by Radiation

    International Nuclear Information System (INIS)

    No, Y. C.; Kuk, I. H.; Song, H. S.

    2006-03-01

    Radiation Technology (RT) has been widely used in most of all fields of industries, medical, bioresources, food and agriculture, public hygiene, and environment. Therefore, its application has been also researched in various parts. For industrialization of the developed technology, not only the application technology will be developed, but the accurate dosimetry and improvement of the services of irradiation practice should be performed as soon as possible. Evaluation of effects and reaction mechanism of biological materials by irradiation was performed in this year in the long term research planning. The researches and experiments were well performed and the good results were obtained. The results may be donated in the progress of radiation biology and the new establishment on the application of RT. Also, one of the results was the evaluation of the structural changes of biomolecules and its application in the fields of food and biotechnology industries. Advanced Radiation Technology Institute (ARTI) will be well settled down and promotion of research activity of newly established institute by the fundamental support of KAERI. And, ARTI can get the goal where the vision of the hub of RT in Asia/Pacific region by 2020

  5. Characterization and optimization of the RA-3 experimental dosimetry for normal sheep lung radio-tolerance study

    International Nuclear Information System (INIS)

    Soto, M.S.; Gonzalez, S.J.; Thorp, Silvia I.; Pozzi, Emiliano; Gadan, M.; Miller, Marcelo; Farias, R.

    2009-01-01

    In the spirit of the novel technique proposed by the University of Pavia group (Italy) to irradiate an isolated organ using BNCT, the Comision Nacional de Energia Atomica (CNEA) in collaboration with the Fundacion Favaloro has initiated a project that aims to investigate the feasibility of BNCT for ex-situ treatment of diffuse metastatic disease in the lungs. The present work was carried out in the framework of the undergoing experimental study of the radio tolerance of normal sheep lung. With the purpose of characterizing and optimizing the resulting experimental dosimetry in normal lung subjected to neutron irradiation in the BNCT facility of the RA-3 reactor (CNEA), we have performed a series of experiments to find the optimum configuration of the container-lung system deriving a dose distribution preferentially uniform throughout the organ. Once the optimal set-up was established, we measured the total gamma dose rate and estimated the irradiation time compatible with the maximum tolerable dose of normal lung resulting from previous studies in rats. This estimation was performed using RBE, CBE and tolerance dose values derived from radiobiological studies with BNCT. In parallel with the experimental characterization, we built two different computational models of the container-lung system to perform Monte Carlo simulation with MCNP and Treatment Planning System NCTPlan. (author)

  6. Radiation dosimetry in nuclear medicine

    International Nuclear Information System (INIS)

    Stabin, M.G.; Tagesson, M.; Ljungberg, M.; Strand, S.E.; Thomas, S.R.

    1999-01-01

    Radionuclides are used in nuclear medicine in a variety of diagnostic and therapeutic procedures. A knowledge of the radiation dose received by different organs in the body is essential to an evaluation of the risks and benefits of any procedure. In this paper, current methods for internal dosimetry are reviewed, as they are applied in nuclear medicine. Particularly, the Medical Internal Radiation Dose (MIRD) system for dosimetry is explained, and many of its published resources discussed. Available models representing individuals of different age and gender, including those representing the pregnant woman are described; current trends in establishing models for individual patients are also evaluated. The proper design of kinetic studies for establishing radiation doses for radiopharmaceuticals is discussed. An overview of how to use information obtained in a dosimetry study, including that of the effective dose equivalent (ICRP 30) and effective dose (ICRP 60), is given. Current trends and issues in internal dosimetry, including the calculation of patient-specific doses and in the use of small scale and microdosimetry techniques, are also reviewed

  7. Neutron personnel dosimetry considerations for fusion reactors

    International Nuclear Information System (INIS)

    Barton, T.P.; Easterly, C.E.

    1979-07-01

    The increasing development of fusion reactor technology warrants an evaluation of personnel neutron dosimetry systems to aid in the concurrent development of a radiation protection program. For this reason, current state of knowledge neutron dosimeters have been reviewed with emphasis placed on practical utilization and the problems inherent in each type of dosimetry system. Evaluations of salient parameters such as energy response, latent image instability, and minimum detectable dose equivalent are presented for nuclear emulsion films, track etch techniques, albedo and other thermoluminescent dosimetry techniques, electrical conductivity damage effects, lyoluminescence, thermocurrent, and thermally stimulated exoelectron emission. Brief summaries of dosimetry regulatory requirements and intercomparison study results help to establish compliance and recent trends, respectively. Spectrum modeling data generated by the Neutron Physics Division of Oak Ridge National Laboratory for the Princeton Tokamak Fusion Test Reactor (TFTR) Facility have been analyzed by both International Commission on Radiological Protection fluence to dose conversion factors and an adjoint technique of radiation dosimetry, in an attempt to determine the applicability of current neutron dosimetry systems to deuterium and tritium fusion reactor leakage spectra. Based on the modeling data, a wide range of neutron energies will probably be present in the leakage spectra of the TFTR facility, and no appreciable risk of somatic injury to occupationally exposed workers is expected. The relative dose contributions due to high energy and thermal neutrons indicate that neutron dosimetry will probably not be a serious limitation in the development of fusion power

  8. Cellular dosimetry

    International Nuclear Information System (INIS)

    Humm, J.L.; Chin, L.M.

    1989-01-01

    Radiation dose is a useful predictive parameter for describing radiation toxicity in conventional radiotherapy. Traditionally, in vitro radiation biology dose-effect relations are expressed in the form of cell survival curves, a semilog plot of cell survival versus dose. However, the characteristic linear or linear quadratic survival curve shape, for high- and low-LET radiations respectively, is only strictly valid when the radiation dose is uniform across the entire target population. With an external beam of 60 Co gamma rays or x-rays, a uniform field may be readily achievable. When radionuclides are incorporated into a cell milieu, several new problems emerge which can result in a departure from uniformity in energy deposition throughout a cell population. This nonuniformity can have very important consequences for the shape of the survival curve. Cases in which perturbations of source uniformity may arise include: 1. Elemental sources may equilibrate in the cell medium with partition coefficients between the extracellular, cytosol, and nuclear compartments. The effect of preferential cell internalization or binding to cell membrane of some radionuclides can increase or decrease the slope of the survival curve. 2. Radionuclides bound to antibodies, hormones, metabolite precursors, etc., may result in a source localization pattern characteristic of the carrier agent, i.e., the sources may bind to cell surface receptors or antigens, be internalized, bind to secreted antigen concentrated around a fraction of the cell population, or become directly incorporated into the cell DNA. We propose to relate the distribution of energy deposition in cell nuclei to biological correlates of cellular inactivation. The probability of each cell's survival is weighted by its individual radiation burden, and the summation of these probabilities for the cell population can be used to predict the number or fraction of cell survivors

  9. EPR dosimetry - present and future

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1999-01-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as co-ordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as biomarkers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (ASTM), and the International Organisation of Standards (ISO) as well as those of the International Commission on Radiation Units and Measurements (ICRU) considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (author)

  10. EPR Dosimetry - Present and Future

    Energy Technology Data Exchange (ETDEWEB)

    Regulla, D.F. [GSF - National Research Centre for Environment and Health, Institute of Radiation Protection, 85764 Neuherberg (Germany)

    1999-07-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  11. EPR Dosimetry - Present and Future

    International Nuclear Information System (INIS)

    Regulla, D.F.

    1999-01-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  12. Energy and entropy in radiation dosimetry and protection

    International Nuclear Information System (INIS)

    Oliveira, A.D.

    2006-01-01

    In this work we present and discuss a proposal to describe the degradation of the energy of photons when they interact with matter, which can be applied in radiation dosimetry and protection. Radiation dosimetry is founded in the well known physical approach of field theory as showed by Roesch and Rossi. Fluence and energy deposited are the most fundamental quantities in radiation dosimetry allowing us to calculate absorbed dose. One of the main characteristics of absorbed dose, sometimes ignored, is that it is an intensive quantity pushing radiation dosimetry into the field of statistical physics. In radiation dosimetry it is often used what we can call collective or macroscopic concepts, such as, for example, effective energy, beam quality or beam hardening and absorbed dose. Some of these concepts are trials to describe macroscopically and with simplicity what happens microscopically with a rather higher degree of complexity. In other words, is a tentative to make a bridge between the non continuous world of atoms and photons to the continuous world of radiation protection dosimetry. In computer simulations, that allow to known accurately the energy deposited in matter, absorbed dose (or fluence) is still a very useful and used quantity; however, some issues are still open problems, source of many discussions in conferences and journals in spite of the development of microdosimetry and nano-dosimetry. In spite of that, macroscopic quantities like absorbed dose are still important quantities. One of the important and controversial open question in biological effects at low doses is the linear no threshold concept (L.N.T.). In our opinion this problem is directly related with the problem mentioned above of the bridge between microscopic and macroscopic concepts. Actually, the extrapolation to low dose region is a good expression of the challenge we have to deal in order to make the connections between both worlds, the discrete micro-world to the continuous macro

  13. Low-energy x-ray dosimetry studies (7 to 17.5 keV) with synchroton radiation

    International Nuclear Information System (INIS)

    Ipe, N.E.; Bellamy, H.; Flood, J.R.

    1995-06-01

    Unique properties of synchrotron radiation (SR), such as its high intensity, brightness, polarization, and broad spectral distribution (extending from x-ray to infra-red wavelengths) make it an attractive light source for numerous experiments. As SR facilities are rapidly being built all over the world, they introduce the need for low-energy x-ray dosemeters because of the potential radiation exposure to experimenters. However, they also provide a unique opportunity for low-energy x-ray dosimetry studies because of the availability of monochromatic x-ray beams. Results of such studies performed at the Stanford Synchrotron Radiation Laboratory are described. Lithium fluoride TLDs (TLD-100) of varying thicknesses (0.015 to 0.08 cm) were exposed free in air to monochromatic x-rays (7 to 17.5 keV). These exposures were monitored with ionization chambers. The response (nC/Gy) was found to increase with increasing TLD thickness and with increasing beam energy. A steeper increase in response with increasing energy was observed with the thicker TLDs. The responses at 7 and 17.5 keV were within a factor of 2.3 and 5.2 for the 0.015 and 0.08 cm-thick TLDs, respectively. The effects of narrow (beam size smaller than the dosemeter) and broad (beam size larger than the dosemeter) beams on the response of the TLDs are also reported

  14. Radiographic film orientation in radiotherapy dosimetry

    International Nuclear Information System (INIS)

    Suchowerska, N.; Davison, A.; Drew, J.; Metcalfe, P.

    1996-01-01

    Since the discovery of x-rays, film has been used as a detection medium for radiation. More recently radiographic film has become established as a practical tool for the measurement of dose distribution in radiotherapy. The accuracy and reproducibility of film dosimetry depends on photon energy, processing conditions and film plane orientation. The relationship between photon energy, processing conditions and film dosimetry accuracy has been studied. The role of film plane orientation is still controversial. The current work aims to clarify the effects film plane orientation has on film dosimetry. Poster 205. (author)

  15. Preclinical acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of ["1"8F]fluorocholine in mice

    International Nuclear Information System (INIS)

    Silveira, Marina B.; Ferreira, Soraya M.Z.M.D.; Nascimento, Leonardo T.C.; Costa, Flávia M.; Mendes, Bruno M.; Ferreira, Andrea V.; Malamut, Carlos; Silva, Juliana B.; Mamede, Marcelo

    2016-01-01

    ["1"8F]Fluorocholine (["1"8F]FCH) has been proven to be effective in prostate cancer. Since ["1"8F]FCH is classified as a new radiopharmaceutical in Brazil, preclinical safety and efficacy data are required to support clinical trials and to obtain its approval. The aim of this work was to perform acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of ["1"8F]FCH. The results could support its use in nuclear medicine as an important piece of work for regulatory in Brazil. - Highlights: • Data demonstrated the high quality, safety and effectiveness of ["1"8F]FCH. • ["1"8F]FCH preclinical profile is in accordance with previously published. • Toxicity, distribution, kinetics and radiation dosimetry were well characterized. • The results are important for regulatory issues in Brazil and other countries.

  16. Numerical analysis for complex thermoluminiscence glow curves.Application to the study of LiF: Ti, Mg and its in radiation dosimetry

    International Nuclear Information System (INIS)

    Gomez Ros, J.M.

    1989-01-01

    A method for the numerical analysis of complex termoluminiscence glow curves based in a modified Marquard Levenberg minimization algorithm is presented. Differents analytical expresions are employed for the individual glow peaks in the cases of first, second and mixed order kinetics, developping aproximated expresions for everyone. These procedures are applied to the caracterization of Lithium Fluoride studying the kinetic order of peaks IV and V. The results obtained permits an interpretation of the complex isothermal decay observed at 165 0 C compatible whith first order kinetics process for both peaks. The aplication to thermoluminiscent dosimetry (TLD) is also described. Other numerical methods are specifically developped to operate whith LiF 8TLD-100) in specific dosimetric aplications of TLD, such environ mental monitoring and mailed dosimetry systems for quality assurance in radiotherapy facilities. The reduction in the minimun detectable dose and the increment in the fiability of the meassurements are some of the advantages obtained over conventional evaluation systems. (Author)

  17. Feasibility and dosimetry studies for 18F-NOS as a potential PET radiopharmaceutical for inducible nitric oxide synthase in humans.

    Science.gov (United States)

    Herrero, Pilar; Laforest, Richard; Shoghi, Kooresh; Zhou, Dong; Ewald, Gregory; Pfeifer, John; Duncavage, Eric; Krupp, Kitty; Mach, Robert; Gropler, Robert

    2012-06-01

    Nitric oxide (NO), the end product of the inducible form of NO synthase (iNOS), is an important mediator of a variety of inflammatory diseases. Therefore, a radiolabeled iNOS radiopharmaceutical for assessing iNOS protein concentration as a marker for its activity would be of value to the study and treatment of NO-related diseases. We recently synthesized an (18)F-radiolabeled analog of the reversible NOS inhibitor, 2-amino-4-methylpyridine ((18)F-NOS), and confirmed its utility in a murine model of lung inflammation. To determine its potential for use in humans, we measured (18)F-NOS myocardial activity in patients after orthotopic heart transplantation (OHT) and correlated it with pathologic allograft rejection, tissue iNOS levels, and calculated human radiation dosimetry. Two groups were studied-a kinetic analysis group and a dosimetry group. In the kinetic analysis group, 10 OHT patients underwent dynamic myocardial (18)F-NOS PET/CT, followed by endomyocardial biopsy. Myocardial (18)F-NOS PET was assessed using volume of distribution; standardized uptake values at 10 min; area under the myocardial moment curve (AUMC); and mean resident time at 5, 10, and 30 min after tracer injection. Tissue iNOS levels were measured by immunohistochemistry. In the dosimetry group, the biodistribution and radiation dosimetry were calculated using whole-body PET/CT in 4 healthy volunteers and 12 OHT patients. The combined time-activity curves were used for residence time calculation, and organ doses were calculated with OLINDA. Both AUMC at 10 min (P measurements with acceptable radiation exposure. Although further modifications to improve the performance of (18)F-NOS are needed, these data show the feasibility of PET of iNOS in the heart and other tissues.

  18. Exposure Setup and Dosimetry for a Study on Effects of Mobile Communication Signals on Human Hematopoietic Stem Cells in vitro

    Directory of Open Access Journals (Sweden)

    M. Rohland

    2017-09-01

    Full Text Available In this paper we describe the design of an exposure setup used to study possible non-thermal effects due to the exposure of human hematopoietic stem cells to GSM, UMTS and LTE mobile communication signals. The experiments are performed under fully blinded conditions in a TEM waveguide located inside an incubator to achieve defined environmental conditions as required for the living cells. Chamber slides containing the cells in culture medium are placed on the septum of the waveguide. The environmental and exposure parameters such as signal power, temperatures, relative humidity and CO2 content of the surrounding atmosphere are monitored permanently during the exposure experiment. The power of the exposure signals required to achieve specific absorption rates of 0.5, 1, 2 and 4 W kg−1 are determined by numerical calculation of the field distribution inside the cell culture medium at 900 MHz (GSM, 1950 MHz (UMTS and 2535 MHz (LTE. The dosimetry is verified both with scattering parameter measurements on the waveguide with and without containers filled with cell culture medium and with temperature measurements with non-metallic probes in separate heating experiments.

  19. Study on the tongue and groove effect of the elekta multileaf collimator using Monte Carlo simulation and film dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Haryanto, F.; Fippel, M.; Bakai, A.; Nuesslin, F. [Dept. of Medical Physics, Radiooncologic Univ. Clinic, Tuebingen (Germany)

    2004-01-01

    Background: nowadays, multileaf collimation of the treatment fields from medical linear accelerators is a common option. Due to the design of the leaf sides, the tongue and groove effect occurs for certain multileaf collimator applications such as the abutment of fields where the beam edges are defined by the sides of the leaves. Material and methods: in this study, the tongue and groove effect was measured for two pairs of irregular multileaf collimator fields that were matched along leaf sides in two steps. Measurements were made at 10 cm depth in a polystyrene phantom using Kodak EDR2 films for a photon beam energy of 6 MV on an elekta sli-plus accelerator. To verify the measurements, full Monte Carlo simulations were done. In the simulations, the design of the leaf sides was taken into account and one component module of BEAM code was modified to correctly simulate the elekta multileaf collimator. Results and conclusion: the results of measurements and simulations are in good agreement and within the tolerance of film dosimetry. (orig.)

  20. Autoradiographic studies of the distribution of radium-226 in rat bone: their implications for human radiation dosimetry and toxicity

    International Nuclear Information System (INIS)

    Priest, N.D.; Haines, J.W.; Howells, G.; Green, D.

    1983-01-01

    A solution containing 226 Ra chloride was injected into young female rats via the saphenous vein. Subsequently, the distribution and retention of the 226 Ra in the skeleton was studied. The results show that 226 Ra is initially deposited in the rat femur as a volume deposit and is fairly evenly distributed throughout the bone matrix. Much of the 226 Ra initially deposited in the skeleton is lost within a few days of its administration. During the first week 226 Ra gradually accumulates at sites of bone deposition including accreting surfaces. Subsequent bone growth results in the burial of contaminated bone surfaces. Following bone resorption some of the 226 Ra released from individual bones is recycled systemically so that all skeletal components tend towards a uniform 226 Ra concentration per unit of bone mineral. Of the two models conventionally used for radiation dosimetry purposes, these results reported for rats suggest that though neither is ideal, the volume distribution model is preferable to the surface model at all times after the uptake of radium by the skeleton. (author)

  1. Radiochromic film dosimetry

    International Nuclear Information System (INIS)

    Xu Zhiyong

    2002-01-01

    Radiochromic film dosimetry was developed to measure ionization irradiation dose for industry and medicine. At this time, there are no comprehensive guideline on the medical application, calibration method and densitometer system for medicine. The review gives update on Radiochromic film dosimetry used for medicine, including principles, film model and material, characteristics, calibration method, scanning densitometer system and medical application

  2. Personal dosimetry in Kazakhstan

    International Nuclear Information System (INIS)

    Khvoshnyanskaya, I.R.; Vdovichenko, V.G.; Lozbin, A.Yu.

    2003-01-01

    KATEP-AE Radiation Laboratory is the first organization in Kazakhstan officially licensed by the Kazakhstan Atomic Energy Committee to provide individual dosimetry services. The Laboratory was established according to the international standards. Nowadays it is the largest company providing personal dosimetry services in the Republic of Kazakhstan. (author)

  3. Developmental biology and the study of malformations.

    Science.gov (United States)

    Hughes, A F

    1976-05-01

    Experimental work on abnormal conditions of incubation in the chick has been undertaken to acquire a scientific approach to malformations. More precise experiments on causing abnormalities had a common origin with experimental embryology. Progress in experimental teratology during the last 50 years is reviewed in a commentary on the 4 principles formulated by Stockard in 1921. The results of cytogenetical studies in man and in other organisms have led to the tracing of some relationships between them. Present knowledge concerning malformations of the neural tube, originating either experimentally, spontaneously, or phenotypically, has been presented and the teratological implications of some recent theories on the expression of the genotype are discussed in particular reference to problems of hormones as teratogens, the implication of carbohydrate metabolism, and teratogenesis. It is speculated that teratogenesis is possibly related to cationic balance in early development and that 1 factor retarding progress in the understanding of malformations is the tendency toward the development of teratology in an adequately close relationship with other branches of cell biology.

  4. 100 years of solid state dosimetry and radiation protection dosimetry

    International Nuclear Information System (INIS)

    Bartlett, David T.

    2008-01-01

    The use of solid state detectors in radiation dosimetry has passed its 100th anniversary. The major applications of these detectors in radiation dosimetry have been in personal dosimetry, retrospective dosimetry, dating, medical dosimetry, the characterization of radiation fields, and also in microdosimetry and radiobiology research. In this introductory paper for the 15th International Conference, I shall speak of the history of solid state dosimetry and of the radiation measurement quantities that developed at the same time, mention some landmark developments in detectors and applications, speak a bit more about dosimetry and measurement quantities, and briefly look at the past and future

  5. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    McLaughlin, W.L.; Boyd, A.W.; Chadwick, K.H.; McDonald, J.C.; Miller, A.

    1989-01-01

    Radiation processing is a relatively young industry with broad applications and considerable commercial success. Dosimetry provides an independent and effective way of developing and controlling many industrial processes. In the sterilization of medical devices and in food irradiation, where the radiation treatment impacts directly on public health, the measurements of dose provide the official means of regulating and approving its use. In this respect, dosimetry provides the operator with a means of characterizing the facility, of proving that products are treated within acceptable dose limits and of controlling the routine operation. This book presents an up-to-date review of the theory, data and measurement techniques for radiation processing dosimetry in a practical and useful way. It is hoped that this book will lead to improved measurement procedures, more accurate and precise dosimetry and a greater appreciation of the necessity of dosimetry for radiation processing. (author)

  6. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Kumar, A.; Reddy, A.R.

    1994-01-01

    The last few years have seen a significant increase in the use of ionising radiation in industrial processes and also international trade in irradiated products. With this, the demand for internationally accepted dosimetric techniques, accredited to international standards has also increased which is further stimulated by the emergence of ISO-9000 series of standards in industries. The present paper describes some of the important dosimetric techniques used in radiation processing, the role of IAEA in evolving internationally accepted standards and work carried out at the Defence Laboratories, Jodhpur in the development of a cheap, broad dose range and simple dosimeter for routine dosimetry. For this polyhydroxy alcohols viz., mannitol, sorbitol and inositol were studied using the spectrophotometric read out method. Out of the alcohols studied mannitol was found to be most promising covering a dose range of 0.01 kGy - 100 kGy. (author). 26 refs., 3 figs., 1 tab

  7. A European neutron dosimetry intercomparison project (ENDIP). Results and evaluation

    International Nuclear Information System (INIS)

    Broerse, J.J.; Burger, G.; Coppola, M.

    1978-01-01

    A total of twenty groups from nine countries participated in sessions of the European Neutron Dosimetry Intercomparison Project (ENDIP) which were held during 1975 at GSF, Munich-Neuherberg and TNO, Rijswijk. The data of all participants are collected, the analysis and evaluation of the results are given in the present report. Specific chapters deal with the experimental arrangements and monitoring results at GSF and TNO, characteristics of the dosimetry systems employed by the paticipating groups and the basic physical data and correction factors employed for the determination of kerma and absorbed dose. In general, the participants in ENDIP quote systematic uncertainties of 7 to 8% in the neutron and total kerma or absorbed dose, which are mainly attributed to inadequate knowledge of basic constants. The variations in the results obtained by different participants seem to be in accordance with the relative large systematic uncertainties quoted. In order to determine the influence of the use of different values for the physical parameters, the relative responses of the participants' dosimeters have also been compared. The variances of quoted kerma and dose values are of the same order of magnitude as those of instrument responses. This result indicates inconsistencies in experimental techniques employed by the participants for the determination of kerma and absorbed dose. A separate nonparametric analysis of the ENDIP results confirmed that there are considerable systematic differences. Recommendations for future studies on neutron dosimetry for biological and medical applications are given at the end of the report

  8. Skeletal dosimetry models for alpha-particles for use in molecular radiotherapy

    Science.gov (United States)

    Watchman, Christopher J.

    Molecular radiotherapy is a cancer treatment methodology whereby a radionuclide is combined with a biologically active molecule to preferentially target cancer cells. Alpha-particle emitting radionuclides show significant potential for use in molecular radiotherapy due to the short range of the alpha-particles in tissue and their high rates of energy deposition. Current radiation dosimetry models used to assess alpha emitter dose in the skeleton were developed originally for occupational applications. In medical dosimetry, individual variability in uptake, translocation and other biological factors can result in poor correlation of clinical outcome with marrow dose estimates determined using existing skeletal models. Methods presented in this work were developed in response to the need for dosimetry models which account for these biological and patient-specific factors. Dosimetry models are presented for trabecular bone alpha particle dosimetry as well as a model for cortical bone dosimetry. These radiation transport models are the 3D chord-based infinite spongiosa transport model (3D-CBIST) and the chord-based infinite cortical transport model (CBICT), respectively. Absorbed fraction data for several skeletal tissues for several subjects are presented. Each modeling strategy accounts for biological parameters, such as bone marrow cellularity, not previously incorporated into alpha-particle skeletal dosimetry models used in radiation protection. Using these data a study investigating the variability in alpha-particle absorbed fractions in the human skeleton is also presented. Data is also offered relating skeletal tissue masses in individual bone sites for a range of ages. These data are necessary for dose calculations and have previously only been available as whole body tissue masses. A revised 3D-CBIST model is also presented which allows for changes in endosteum thickness to account for revised target cell location of tissues involved in the radiological

  9. Dosimetry in radioisotope placentography

    International Nuclear Information System (INIS)

    Sastry, K.G.K.; Reddy, A.R.; Nagaratnam, A.

    1976-01-01

    Radionuclide investigation of the placenta is being widely used in recent years for the diagnosis and management of vaginal bleeding in the third trimester of pregnancy. One is, therefore, concerned about the radiation exposure to the foetus during such procedures. In the present communication a precise method of estimation of radiation doses is presented. A concept termed 'effective absorbed dose constant' is utilized to enable the absorbed fractions and equilibrium absorbed dose constants to be more easily employed in radiation dose estimations. Tables of the effective absorbed dose constants for radionuclides like 131 I, 123 I, sup(113m)Tc, sup(99m)Tc, 67 Ga, and 51 Cr, are given for different masses and shapes. Masses of different organs of both mother and foetus at different periods of pregnancy and the biological turnover data for different radiopharmaceuticals are reviewed and typical values are presented. Radiation doses to different organs of both mother and foetus at the 30th week of pregnancy are finally estimated for 131 I-HSA, 123 I-SHA, sup(99m)Tc-HSA and sup(113m)In-chloride. The advantage of the effective absorbed dose constants in radiation dosimetry in general is discussed. The relative merits of different radiopharmaceuticals for placental investigations are brought out in comparison with antenatal pelvimetric and abdominal X-ray investigations, from the point of view of radiation doses. (author)

  10. Cytogenetics for dosimetry in cases of radiation accidents and assessing the safety of irradiated food material

    International Nuclear Information System (INIS)

    Natarajan, A.T.; Kesavan, P.C.

    2005-01-01

    One of the many areas of research initiated by Swaminathan at the Botany Division of the Indian Agricultural Research Institute, New Delhi was radiation cytogenetics, which involves study of induced chromosomal aberrations. These studies had impact not only on elucidating basic mechanisms involved in the formation of chromosomal aberrations, but also several practical applications related to human health. In this review, we briefly summarize two applications, namely biological dosimetry following radiation accidents and safety of irradiated food material. (author)

  11. Postgraduate studies in radiation biology in Europe

    International Nuclear Information System (INIS)

    Trott, K.R.; Lohmann, P.H.M.; Zeeland, A.A. van; Natarajan, A.T.; Schibilla, H.; Chadwick, K.; Kellerer, A.M.; Steinhaeusler, F.

    1998-01-01

    The present system of radiobiological research in universities and research centres is no longer able to train radiobiologists who have a comprehensive understanding of the entire field of radiation biology including both 'classical' and molecular radiation biology. However, such experts are needed in view of the role radiation protection plays in our societies. No single institution in Europe could now run a 1-year, full-time course which covers all aspects of the radiobiological basis of radiation protection. Therefore, a cooperative action of several universities from different EU member states has been developed and is described herein. (orig.)

  12. Dosimetry of nasal uptake of soluble and reactive gases: A first study of inter-human variability (Journal Article)

    Science.gov (United States)

    Anatomically accurate human child and adult nasal tract models will be used in concert with computationally simulated air flow information to investigate the influence of age-related differences in anatomy on inhalation dosimetry in the upper and lower airways. The findings of t...

  13. Dosimetry techniques applied to thermoluminescent age estimation

    International Nuclear Information System (INIS)

    Erramli, H.

    1986-12-01

    The reliability and the ease of the field application of the measuring techniques of natural radioactivity dosimetry are studied. The natural radioactivity in minerals in composed of the internal dose deposited by alpha and beta radiations issued from the sample itself and the external dose deposited by gamma and cosmic radiations issued from the surroundings of the sample. Two technics for external dosimetry are examined in details. TL Dosimetry and field gamma dosimetry. Calibration and experimental conditions are presented. A new integrated dosimetric method for internal and external dose measure is proposed: the TL dosimeter is placed in the soil in exactly the same conditions as the sample ones, during a time long enough for the total dose evaluation [fr

  14. Dosimetry of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez C, G; Restrepo, J; Aguirre, C A [Hospital Universitario del Valle, Cali (Colombia)

    1996-08-01

    The systemic therapy of breast cancer has also changed profoundly during the last 60 years, and in this time the integration of treatment modalities involve a major area of investigation. The dosimetry of breast cancer presents different complications which can range from the Physician`s handling of the neoplasia up to the simple aspects of physical simulation, contour design, radiation fields, irregular surfaces and computer programs containing mathematical equations which differ little or largely with the reality of the radiation distribution into the volume to be irradiated. We have studied the problem using two types of measurements to determine how the radiation distribution is in irregular surfaces, and designing an easier skill to be used with each patient, in order to optimize the treatment with respect to the simulation and verification process. (author). 7 refs.

  15. Study of biocompatible and biological materials

    CERN Document Server

    Pecheva, Emilia

    2017-01-01

    The book gives an overview on biomineralization, biological, biocompatible and biomimetic materials. It reveals the use of biomaterials alone or in composites, how their performance can be improved by tailoring their surface properties by external factors and how standard surface modification techniques can be applied in the area of biomaterials to beneficially influence their growth on surfaces.

  16. 15N in biological nitrogen fixation studies

    International Nuclear Information System (INIS)

    Faust, H.

    1986-05-01

    A bibliography with 298 references on the use of the stable nitrogen isotope 15 N in the research on the biological fixation of dinitrogen is presented. The literature pertaining to this bibliography covers the period from 1975 to the middle of 1985. (author)

  17. High energy dosimetry

    International Nuclear Information System (INIS)

    Ruhm, W.

    2010-01-01

    Full text: Currently, quantification of doses from high-energy radiation fields is a topical issue. This is so because high-energy neutrons play an important role for radiation exposure of air crew members and personnel outside the shielding of ion therapy facilities. In an effort to study air crew exposure from cosmic radiation in detail, two Bonner Sphere Spectrometers (BSSs) have recently been installed to measure secondary neutrons from cosmic radiation, one at the environmental research station 'Schneefernerhaus' at an altitude of 2650 m on the Zugspitze mountain, Germany, the other at the Koldewey station close to the North Pole on Spitsbergen. Based on the measured neutron fluence distributions and on fluence-to-dose conversion coefficients, mean ambient dose equivalent rate values of 75.0 ± 2.9 nSv/h and 8.7 ± 0.6 nSv/h were obtained for October 2008, respectively. Neutrons with energies above about 20 MeV contribute about 50% to dose, at 2650 m. Ambient dose equivalent rates measured by means of a standard rem counter and an extended rem counter at the Schneefernerhaus confirm this result. In order to study the response of state-of-the-art radiation instrumentation in such a high-energy radiation field, a benchmark exercise that included both measurements in and simulation of the stray neutron radiation field at the high-energy particle accelerator at GSI, Germany, were performed. This CONRAD (COordinated Network for RAdiation Dosimetry) project was funded by the European Commission, and the organizational framework was provided by the European Radiation Dosimetry Group, EURADOS. The Monte Carlo simulations of the radiation field and the experimental determination of the neutron spectra with various Bonner Sphere Spectrometers suggest the neutron fluence distributions to be very similar to those of secondary neutrons from cosmic radiation. The results of this intercomparison exercise in terms of ambient dose equivalent are also discussed

  18. Radiation risk assessment in neonatal radiographic examinations of the chest and abdomen: a clinical and Monte Carlo dosimetry study

    International Nuclear Information System (INIS)

    Makri, T; Yakoumakis, E; Papadopoulou, D; Gialousis, G; Theodoropoulos, V; Sandilos, P; Georgiou, E

    2006-01-01

    Seeking to assess the radiation risk associated with radiological examinations in neonatal intensive care units, thermo-luminescence dosimetry was used for the measurement of entrance surface dose (ESD) in 44 AP chest and 28 AP combined chest-abdominal exposures of a sample of 60 neonates. The mean values of ESD were found to be equal to 44 ± 16 μGy and 43 ± 19 μGy, respectively. The MCNP-4C2 code with a mathematical phantom simulating a neonate and appropriate x-ray energy spectra were employed for the simulation of the AP chest and AP combined chest-abdominal exposures. Equivalent organ dose per unit ESD and energy imparted per unit ESD calculations are presented in tabular form. Combined with ESD measurements, these calculations yield an effective dose of 10.2 ± 3.7 μSv, regardless of sex, and an imparted energy of 18.5 ± 6.7 μJ for the chest radiograph. The corresponding results for the combined chest-abdominal examination are 14.7 ± 7.6 μSv (males)/17.2 ± 7.6 μSv (females) and 29.7 ± 13.2 μJ. The calculated total risk per radiograph was low, ranging between 1.7 and 2.9 per million neonates, per film, and being slightly higher for females. Results of this study are in good agreement with previous studies, especially in view of the diversity met in the calculation methods

  19. Radiation risk assessment in neonatal radiographic examinations of the chest and abdomen: a clinical and Monte Carlo dosimetry study

    Science.gov (United States)

    Makri, T.; Yakoumakis, E.; Papadopoulou, D.; Gialousis, G.; Theodoropoulos, V.; Sandilos, P.; Georgiou, E.

    2006-10-01

    Seeking to assess the radiation risk associated with radiological examinations in neonatal intensive care units, thermo-luminescence dosimetry was used for the measurement of entrance surface dose (ESD) in 44 AP chest and 28 AP combined chest-abdominal exposures of a sample of 60 neonates. The mean values of ESD were found to be equal to 44 ± 16 µGy and 43 ± 19 µGy, respectively. The MCNP-4C2 code with a mathematical phantom simulating a neonate and appropriate x-ray energy spectra were employed for the simulation of the AP chest and AP combined chest-abdominal exposures. Equivalent organ dose per unit ESD and energy imparted per unit ESD calculations are presented in tabular form. Combined with ESD measurements, these calculations yield an effective dose of 10.2 ± 3.7 µSv, regardless of sex, and an imparted energy of 18.5 ± 6.7 µJ for the chest radiograph. The corresponding results for the combined chest-abdominal examination are 14.7 ± 7.6 µSv (males)/17.2 ± 7.6 µSv (females) and 29.7 ± 13.2 µJ. The calculated total risk per radiograph was low, ranging between 1.7 and 2.9 per million neonates, per film, and being slightly higher for females. Results of this study are in good agreement with previous studies, especially in view of the diversity met in the calculation methods.

  20. SU-F-T-17: A Feasibility Study for the Transit Dosimetry with a Glass Dosimeter in Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Moon, S; Yoon, M [Korea University, Seoul (Korea, Republic of); Chung, W; Chung, M; Kim, D [Kyung Hee University Hospital at Gangdong, Gangdonggu, Seoul (Korea, Republic of)

    2016-06-15

    Purpose: Confirming the dose delivered to a patient is important to make sure the treatment quality and safety of the radiotherapy. Measuring a transit dose of the patient during the radiotherapy could be an interesting way to confirm the patient dose. In this study, we evaluated the feasibility of the transit dosimetry with a glass dosimeter in brachytherapy. Methods: We made a phantom that inserted the glass dosimeters and placed under patient lying on a couch for cervix cancer brachytherapy. The 18 glass dosimeters were placed in the phantom arranged 6 per row. A point putting 1cm vertically from the source was prescribed as 500.00 cGy. Solid phantoms of 0, 2, 4, 6, 8, 10 cm were placed between the source and the glass dosimeter. The transit dose was measured each thickness using the glass dosimeters and compared with a treatment planning system (TPS). Results: When the transit dose was smaller than 10 cGy, the average of the differences between measured values and calculated values by TPS was 0.50 cGy and the standard deviation was 0.69 cGy. If the transit dose was smaller than 100 cGy, the average of the error was 1.67 ± 4.01 cGy. The error to a point near the prescription point was −14.02 cGy per 500.00 cGy of the prescription dose. Conclusion: The distances from the sources to skin of the patient generally are within 10 cm for cervix cancer cases in brachytherapy. The results of this preliminary study showed the probability of the glass dosimeter as the transit dosimeter in brachytherapy.

  1. Polymer gel dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Baldock, C [Institute of Medical Physics, School of Physics, University of Sydney (Australia); De Deene, Y [Radiotherapy and Nuclear Medicine, Ghent University Hospital (Belgium); Doran, S [CRUK Clinical Magnetic Resonance Research Group, Institute of Cancer Research, Surrey (United Kingdom); Ibbott, G [Radiation Physics, UT M D Anderson Cancer Center, Houston, TX (United States); Jirasek, A [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Lepage, M [Centre d' imagerie moleculaire de Sherbrooke, Departement de medecine nucleaire et de radiobiologie, Universite de Sherbrooke, Sherbrooke, QC (Canada); McAuley, K B [Department of Chemical Engineering, Queen' s University, Kingston, ON (Canada); Oldham, M [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Schreiner, L J [Cancer Centre of South Eastern Ontario, Kingston, ON (Canada)], E-mail: c.baldock@physics.usyd.edu.au, E-mail: yves.dedeene@ugent.be

    2010-03-07

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented. (topical review)

  2. THERMOLUMINESCENT DOSIMETRY

    Energy Technology Data Exchange (ETDEWEB)

    Malsky, Stanley J.; Amato, Charles G.; Roswit, Bernard

    1963-06-15

    The performance of CaF/sub 2/: Mn and LiF as thermoluminescent in vivo dosimeters is studied. The facility with which this type of dosimeter can be inserted into the body is discussed. The dosimeter is inserted into the body by trocar or catheter techniques and exposed to radiation; it is then removed and heated, and the thermoluminescence is measured and used as an indication of the absorbed dose. (T.F.H.)

  3. The Vinca dosimetry experiment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1962-03-15

    On 15 October 1958 there occurred a very brief uncontrolled run of the zero-power reactor at the Boris Kidric Institute of Nuclear Science, Vinca, near Belgrade, Yugoslavia. During this run six persons received various doses of radiation. They were subsequently given medical treatment of a novel kind at the Curie Hospital, Paris. In atomic energy operations to date, very few accidents involving excessive radiation exposure to human beings have occurred. In fact, the cases of acute radiation injury are limited to about 30 known high exposures, few of which were in the lethal or near-lethal range. Since direct experiment to determine the effects of ionizing radiation on man is unacceptable, information on these effects has to be based on a consideration of data relating to accidental exposures, viewed in the light of the much more extensive data obtained from experiments on animals. Therefore, any direct information on the effects of radiation on humans is very valuable. The international dosimetry project described in this report was carried out at Vinca, Yugoslavia, under the auspices of the International Atomic Energy Agency to determine the precise amount of radiation to which the persons had been exposed during the accident. These dosimetry data, together with the record of the carefully observed clinical effects, are of importance both for the scientific study of radiation effects on man and for the development of methods of therapy. The experiment and measurements were carried out at the end of April 1960. The project formed part of the Agency's research programme in the field of health and safety. The results of the experiment are made available through this report to all Member States.

  4. The Vinca dosimetry experiment

    International Nuclear Information System (INIS)

    1962-03-01

    On 15 October 1958 there occurred a very brief uncontrolled run of the zero-power reactor at the Boris Kidric Institute of Nuclear Science, Vinca, near Belgrade, Yugoslavia. During this run six persons received various doses of radiation. They were subsequently given medical treatment of a novel kind at the Curie Hospital, Paris. In atomic energy operations to date, very few accidents involving excessive radiation exposure to human beings have occurred. In fact, the cases of acute radiation injury are limited to about 30 known high exposures, few of which were in the lethal or near-lethal range. Since direct experiment to determine the effects of ionizing radiation on man is unacceptable, information on these effects has to be based on a consideration of data relating to accidental exposures, viewed in the light of the much more extensive data obtained from experiments on animals. Therefore, any direct information on the effects of radiation on humans is very valuable. The international dosimetry project described in this report was carried out at Vinca, Yugoslavia, under the auspices of the International Atomic Energy Agency to determine the precise amount of radiation to which the persons had been exposed during the accident. These dosimetry data, together with the record of the carefully observed clinical effects, are of importance both for the scientific study of radiation effects on man and for the development of methods of therapy. The experiment and measurements were carried out at the end of April 1960. The project formed part of the Agency's research programme in the field of health and safety. The results of the experiment are made available through this report to all Member States

  5. Dosimetry in intravascular brachytherapy

    International Nuclear Information System (INIS)

    Campos, Laelia Pumilla Botelho

    2000-03-01

    Among the cardiovascular diseases responsible for deaths in the adult population in almost all countries of the world, the most common is acute myocardial infarction, which generally occurs because of the occlusion of one or more coronary arteries. Several diagnostic techniques and therapies are being tested for the treatment of coronary artery disease. Balloon angioplasty has been a popular treatment which is less invasive than traditional surgeries involving revascularization of the myocardium, thus promising a better quality of life for patients. Unfortunately, the rate of restenosis (re-closing of the vessel) after balloon angioplasty is high (approximately 30-50% within the first year after treatment).Recently, the idea of delivering high radiation doses to coronary arteries to avoid or delay restenosis has been suggested. Known as intravascular brachytherapy, the technique has been used with several radiation sources, and researchers have obtained success in decreasing the rate of restenosis in some patient populations. In order to study the radiation dosimetry in the patient and radiological protection for the attending staff for this therapy, radiation dose distributions for monoenergetic electrons and photons (at nine discrete energies) were calculated for blood vessels of diameter 0.15, o,30 and 0.45 cm with balloon and wire sources using the radiation transport code MCNP4B. Specific calculations were carried out for several candidate radionuclides as well. Two s tent sources (metallic prosthesis that put inside of patient's artery through angioplasty) employing 32 P are also simulated. Advantages and disadvantages of the various radionuclides and source geometries are discussed. The dosimetry developed here will aid in the realization of the benefits obtained in patients for this promising new technology. (author)

  6. Scientific days on electromagnetic fields: from dosimetry to human health - Conference proceedings; Journees scientifiques - Champs electromagnetiques: de la dosimetrie a la sante humaine - Recueil des resumes et presentations

    Energy Technology Data Exchange (ETDEWEB)

    Wiart, J.; Ghanmi, A.; Picon, O.; Conil, E.; Varsier, N.; Hadjem, A.; Sudret, B.; Magne, I.; Souques, M.; Gaudaire, F.; De Seze, R.; Jawad, O.; Lautru, D.; Dricot, J.M.; Horlin, F.; De Doncker, P.; Drissaoui, A.; Musy, F.; Nicolas, L.; Perrussel, R.; Scorretti, R.; Voyer, D.; Jala, M.; Moulines, E.; Levy-Leduc, C.; Mahfouz, Z.; Gati, A.; Fouad Hanna, V.; Leveque, P.; Arnaud-Cormos, D.; Zhadobov, M.; Jarrige, P.; Gaborit, G.; Kohler, S.; Ticaud, N.; Duvillaret, L.; Guelilia, Z.; Loison, R.; Gillard, R.; Laisne, A.; Favet, D.; Benadhira, R.; Mir, L.; Nadi, M.; Kourtiche, D.; Gazeau, F.; Wilhelm, C.; Delemotte, L.; Breton, M.; Tarek, M.; Marc-Vergnes, J.P.; Yardin, C.; Perrin, A.; Le Drean, Y.; Sauleau, R.; Lambrozo, J.; Selmaoui, B.; Ghosn, R.; Thuroczy, G.; Villegier, A.S.; Loos, N.; Brenet-Dufour, V.; Liabeuf, S.; Bach, V.; Moretti, D.; Lewis, N.; Garenne, A.; Poulletier De Gannes, F.; Haro, E.; Lagroye, I.; Bornat, Y.; Boutaib, Y.; Saighi, S.; Renaud, S.; Veyre, B.; Schuz, J.; Deltour, I.; Van Deventer, E.; Vecchia, P.; Merckel, O.; Bellaouel, A.; Demaret, P.; Donati, P.; Jovanovic, D.; Chauvin, S.; Desreumaux, J.P.; Fouquet, L.; Picard, D.; Massardier-Pilonchery, A.; Hours, M.; Bergeret, A.; Person, C.; Toutain, Y.; Butet, R.; Berrahma, K.; Balderelli, I.; Stelmaszyk, V.; Cretallaz, C.; Lamproglou, I.; Amourette, C.; Diserbo, M.; Fauquette, W.; Martigne, P.; Collin, A.; Lagroye, I.; Ait Aissa, S.; Hurtier, A.; Taxile, M.; Le Montagner, L.; Athane, A.; Duleu, S.; Percherancier, Y.; Geffard, M.; Ruffie, G.; Billaudel, B.; Veyret, B.; Pelletier, A.; Delanaud, S.; Libert, J.P.; Schunck, T.; Bieth, F.; Soubere Mahamoud, Y.; Le Quement, C.; Ferrand, G.; Le Guevel, R.; Carton, P.H.; Luong, M.; Tanvir, S.; Selmaoui, B.; Silva Pires-Antonietti, V.; Sonnet, P.; Pulvin, S.; Kuster, O.; Tetelin, C.

    2012-04-15

    This document brings together the available presentations (articles and slides) given at the URSI scientific days on electromagnetic fields: dosimetry, peoples' exposure, biological and health risks, risk management, and medical uses. 48 presentations are compiled in this document and deal with: 1 - Stochastic dosimetry: variability challenge; 2 - How to estimate the exposure to 50/60 Hz magnetic field in an epidemiological study?; 3 - Joint analysis of population exposure and radio coverage of GSM and UMTS mobile phone networks; 4 - Study of the specific energy absorption rate (SAR) sensitiveness to phone positions near the head for 2 GSM mobile phones; 5 - Statistical Study of SAR under Wireless Channel - Exposure in Indoor Environment; 6 - Uncertainty propagation in numerical dosimetry: how to reduce calculation costs?; 7 - Use of a simplified pregnant woman model for foetus exposure analysis; 8 - SAR estimation using multi-exposure with a mobile phone; 9 - State-of-the-art in experimental dosimetry (RF and pulses); 10 - Mm-waves dosimetry: issues, stakes and actual solutions; 11 - Use of DG-FDTD for a dosimetry calculation in a strongly multi-scale problem: determination of the eye-SAR near a HF/VHF vehicle-borne source; 12 - Dosimetric measurements with a fiber-type electro-optical sensor; 13 - Partial experimental evaluation of basic restrictions in the HF/VHF range; 14 - Repetitive trans-cranial magnetic stimulation Stimulation (rTMS) in psychiatry: present day situation and perspectives; 15 - Medical applications of electric fields; 16 - Measurements for life: new perspectives? 17 - Nano-particles and magnetic stimuli for medical imaging and therapy; 18 - Molecular Insights into electroporation and siRNA electro-transfer through model cell membranes; 19 - State of knowledge on electromagnetic fields hypersensitivity (HS-CEM); 20 - Experimentation methodology: from results to interpretation; 22 - Mm waves - update on biological effects at 40-60 GHz; 23

  7. Theoretical basis for dosimetry

    International Nuclear Information System (INIS)

    Carlsson, G.A.

    1985-01-01

    Radiation dosimetry is fundamental to all fields of science dealing with radiation effects and is concerned with problems which are often intricate as hinted above. A firm scientific basis is needed to face increasing demands on accurate dosimetry. This chapter is an attempt to review and to elucidate the elements for such a basis. Quantities suitable for radiation dosimetry have been defined in the unique work to coordinate radiation terminology and usage by the International Commission on Radiation Units and Measurements, ICRU. Basic definitions and terminology used in this chapter conform with the recent ''Radiation Quantities and Units, Report 33'' of the ICRU

  8. Dosimetry for radiation processing

    International Nuclear Information System (INIS)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both by international organizations (IAEA) and national laboratories have helped to improve the reliability of dose measurements. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading to traceable and reliable dosimetry are discussed. (author)

  9. Carbon Nanomaterials in Biological Studies and Biomedicine.

    Science.gov (United States)

    Teradal, Nagappa L; Jelinek, Raz

    2017-09-01

    The "carbon nano-world" has made over the past few decades huge contributions in diverse scientific disciplines and technological advances. While dramatic advances have been widely publicized in using carbon nanomaterials such as fullerenes, carbon nanotubes, and graphene in materials sciences, nano-electronics, and photonics, their contributions to biology and biomedicine have been noteworthy as well. This Review focuses on the use of carbon nanotubes (CNTs), graphene, and carbon quantum dots [encompassing graphene quantum dots (GQDs) and carbon dots (C-dots)] in biologically oriented materials and applications. Examples of these remarkable nanomaterials in bio-sensing, cell- and tissue-imaging, regenerative medicine, and other applications are presented and discussed, emphasizing the significance of their unique properties and their future potential. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Development and current state of dosimetry in Cuba

    International Nuclear Information System (INIS)

    Prieto Miranda, E.F.; Cuesta Fuente, G.; Chavez Ardanza, A.

    1999-01-01

    In Cuba, the application of the radiation technologies has been growing in the last years, and at present there are several dosimetry systems with different ranges of absorbed dose. Diverse researches were carried out on high dose dosimetry with the following dosimetry systems: Fricke, ceric-cerous sulfate, ethanol-chlorobenzene, cupric sulfate and Perspex (Red 4034 AE and Clear HX). In this paper the development achieved during the last 15 years in the high dose dosimetry for radiation processing in Cuba is presented, as well as, the current state of different dosimetry systems employed for standardization and for process control. The paper also reports the results of dosimetry intercomparison studies that were performed with the Ezeiza Atomic Center of Argentine and the International Dose Assurance Service (IDAS) of IAEA. (author)

  11. Neutron personal dosimetry: state-of-art

    International Nuclear Information System (INIS)

    Spurný, František

    2005-03-01

    State-of-art of the personal neutron dosimetry is presented, analysed and discussed. Particular attention is devoted to the problems of this type of the dosimetry of external exposure for radiation fields at nuclear power plants. A review of general problems of neutron dosimetry is given and the active individual dosimetry methods available and/or in the stage of development are briefly reviewed. Main attention is devoted to the analysis of the methods available for passive individual neutron dosimetry. The characteristics of these dosemeters were studied and are compared: their energy response functions, detection thresholds and the highest detection limits, the linearity of response, the influence of environmental factors, etc. Particular attention is devoted to their behavior in reactor neutron fields. It is concluded that the choice of the neutron personal dosemeter depends largely on the conditions in which the instrument should be used (neutron spectrum, the level of exposure and the exposure rate, etc.). The results obtained with some of these dosemeters during international intercomparisons are also presented. Particular attention is paid to the personal neutron dosimeter developed and routinely used by National Personal Dosimetry Service Ltd. in the Czech Republic. (author)

  12. Complete Biological Evaluation of Therapeutical Radiopharmaceuticals in Rodents, Laboratory Beagles and Veterinary Patients - Preclinical Distribution-, Kinetic-, Excretion-, Internal Dosimetry-, Radiotoxicological-, Radiation Safety- and Efficacy Data

    International Nuclear Information System (INIS)

    Balogh, L.; Domokos, M.; Polyak, A.; Thuroczy, J.; Janoki, G.

    2009-01-01

    The research and development of various novel therapeutical radiopharmaceuticals is a huge demand in many laboratories world-wide. Beside of multiple bone metastases pain-palliation and radiosynovectomy agents a number of specific radiopharmaceutical applicants mainly for oncological applications are in the pipeline. Numerous in vitro methods are available in the first line to test the radiolabelling efficiency, the possible radioactive and non-labelled impurities, the stability of the label at different conditions and mediums, and some specific characteristics of radiopharmaceutical applicants eg.: receptor binding assays, antigen-antibody assays. But, still before human clinical trials there are several questions to be solved in regards of toxicology, radiotoxicology, radiation safety and maybe most importantly the efficacy tasks. All these issues cannot be answered without animal tests. Several decades back animal tests in radiopharmacy meant only standard bioassays in a large number of healthy rodents. Later on pathological models eg.: human tumor xenografts in immunodeficient animals came-out and through them radiopharmaceutical tumor-uptake by the targets were available to evaluate in vivo as well. Xenografts are still popular and widely used models in the field but instead of wide-scaled bioassays nowadays repeated scintiscans or hybrid images (SPECT/CT, PET/CT) are more and more often used to answer kinetic-, excretion-, tumor uptake, internal dosimetry (Minimum Effective Dose, Maximum Tolerable Dose, critical organ doses, tumor doses) questions. Greater animals like laboratory Beagles are more closely in size, clinical and metabolic parameters to the human objects so playing a more perfect role of human medical doctor and especially veterinary patients. Easy to understand that many of the spontaneously occurring companion animal diseases are a good model of human pathological diseases. The need of a better diagnosis and treatment of that animals meets with

  13. Dosimetry of β extensive sources

    International Nuclear Information System (INIS)

    Rojas C, E.L.; Lallena R, A.M.

    2002-01-01

    In this work, we have been studied, making use of the Penelope Monte Carlo simulation code, the dosimetry of β extensive sources in situations of spherical geometry including interfaces. These configurations are of interest in the treatment of the called cranealfaringyomes of some synovia leisure of knee and other problems of interest in medical physics. Therefore, its application can be extended toward problems of another areas with similar geometric situation and beta sources. (Author)

  14. Fast neutron spectrometry and dosimetry; Spectrometrie et dosimetrie des neutrons rapides

    Energy Technology Data Exchange (ETDEWEB)

    Blaize, S; Ailloud, J; Mariani, J; Millot, J P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    We have studied fast neutron spectrometry and dosimetry through the recoil protons they produce in hydrogenated samples. In spectrometric, we used nuclear emulsions, in dosimetric, we used polyethylene coated with zinc sulphide and placed before a photomultiplier. (author)Fren. [French] Nous avons etudie la spectrometrie et la dosimetrie des neutrons rapides en utilisant les protons de recul qu'ils produisent dans une matiere hydrogenee. En spectrometrie, nous avons employe des emulsions nucleaires, en dosimetrie, du polyethylene recouvert de sulfure de zinc place devant un photomultiplicateur. (auteur)

  15. Chernobyl Experience in the Field of Retrospective Dosimetry

    International Nuclear Information System (INIS)

    Chumak, V.; Bakhanova, E.

    2011-01-01

    Chernobyl accident, which occurred on April 26, 1986 at NPP located less than 150 km north of Kiev, is the largest nuclear accident ever. Unprecedented scale of the accident was determined not only by the amount of released activity, but also by a number of population and workers involved and, therefore, exposed to enhanced doses of ionizing radiation. Population of the 30-km exclusion zone numbering about 116,000 persons of all ages and both genders was evacuated within days and weeks after the accident, emergency workers called ''liquidators of the accident'' (males age 20-50) were involved into clean-up and recovery for 5 years and their number is estimated as 600,000, about 300,000 are Ukrainian citizens. Due to unexpected and excessively large scale accident, none of residents had personal dosimeters, personal dosimetry of liquidators was not total, dosimetry techniques and practices were far from the optimum. As a result, an acute need for retrospective dose assessment was dictated by radiation protection and research considerations. This need was responded by implementation of wide scale dose reconstruction efforts, which covered main exposed cohorts and encompassed broad variety of newly developed methods: analytical (time-and-motion), modeling, biological and physical (EPR spectroscopy of teeth, TL of quartz). The presentation summarizes vast experience accumulated by RCRM in the field of retrospective dosimetry of large cohorts of exposed population and professionals. These dose reconstruction projects were implemented, in particular, in the framework of epidemiological studies, designed to follow-up medical consequences of Chernobyl accident and study health effects of ionizing radiation, in particular, Ukrainian-American studies of cataracts and leukemia among liquidators. Over 25 years passed after Chernobyl accident a broad variety of retrospective dosimetry problems was addressed by the team of Research Center for Radiation Medicine AMS Ukraine. In

  16. Microbiological control of sterilization efficiency by irradiation. Biological indicators. [Medical supplies

    Energy Technology Data Exchange (ETDEWEB)

    Bates, C [Institut National des Radioelements, Brussels (Belgium)

    1977-01-01

    The microbiological efficiency of the radiosterilization process was tested by means of biological indicators such as Micrococcus radiodurans R1 and Bacillus pumilus E601 for gamma and electron radiation doses ranging from 0.5 to 6 Mrad. The response of the biological indicators was studied in terms of conservation time, initial concentration of biological material, and sources of used radiation. Both the biological dosimetry of the process and the sterility after treatment were studied on the basis of inactivation curves.

  17. The importance of BMI in dosimetry of 153Sm-EDTMP bone pain palliation therapy: A Monte Carlo study

    International Nuclear Information System (INIS)

    Fallahpoor, Maryam; Abbasi, Mehrshad; Asghar Parach, Ali; Kalantari, Faraz

    2017-01-01

    Using digital phantoms as an atlas compared to acquiring CT data for internal radionuclide dosimetry decreases patient overall radiation dose and reduces the required analysis effort and time for organ segmentation. The drawback is that the phantom may not match exactly with the patient. We assessed the effect of varying BMIs on dosimetry results for a bone pain palliation agent, 153 Sm-EDTMP. The simulation was done using the GATE Monte Carlo code. Female XCAT phantoms with the following different BMIs were employed: 18.6, 20.8, 22.1, 26.8, 30.3 and 34.7 kg/m 2 . S-factors (mGy/MBq.s) and SAFs (kg −1 ) were calculated for the dosimetry of the radiation from major source organs including spine, ribs, kidney and bladder into different target organs as well as whole body dosimetry from spine. The differences in dose estimates from different phantoms compared to those from the phantom with BMI of 26.8 kg/m 2 as the reference, were calculated for both gamma and beta radiations. The relative differences (RD) of the S-factors or SAFs from the values of reference phantom were calculated. RDs greater than 10% and 100% were frequent in radiations to organs for photon and beta particles, respectively. The relative differences in whole body SAFs from the reference phantom were 15.4%, 7%, 4.2%, −9.8% and −1.4% for BMIs of 18.6, 20.8, 22.1, 30.3 and 34.7 kg/m 2 , respectively. The differences in whole body S-factors for the phantoms with BMIs of 18.6, 20.8, 22.1, 30.3 and 34.7 kg/m 2 were 39.5%, 19.4%, 8.8%, −7.9% and −4.3%, respectively. The dosimetry of the gamma photons and beta particles changes substantially with the use of phantoms with different BMIs. The change in S-factors is important for dose calculation and can change the prescribed therapeutic dose of 153 Sm-EDTMP. Thus a phantom with BMI better matched to the patient is suggested for therapeutic purposes where dose estimates closer to those in the actual patient are required. - Highlights: • Internal

  18. Relative dosimetry by Ebt-3

    International Nuclear Information System (INIS)

    De Leon A, M. A.; Rivera M, T.; Hernandez O, J. O.

    2015-10-01

    In the present work relative dosimetry in two linear accelerator for radiation therapy was studied. Both Varian Oncology systems named Varian Clinac 2100-Cd and MLC Varian Clinac i X were used. Gaf Chromic Ebt-3 film was used. Measurements have been performed in a water equivalent phantom, using 6 MV and 18 MV photon beams on both Linacs. Both calibration and Electron irradiations were carried out with the ionization chamber placed at the isocenter, below a stack of solid water slabs, at the depth of dose maximum (D max), with a Source-to-Surface Distance (SSD) of 100 cm and a field size of 10 cm x 10 cm. Calibration and dosimetric measurements photons were carried out under IAEA-TRS 398 protocol. Results of relative dosimetry in the present work are discussed. (Author)

  19. Individual neutron dosimetry

    International Nuclear Information System (INIS)

    Mauricio, C.L.P.

    1987-01-01

    The most important concepts and development in individual neutron dosimetry are presented, especially the dosimetric properties of the albedo technique. The main problem in albedo dosimetry is to calibrate the dosemeter in the environs of each neutron source. Some of the most used calibration techniques are discussed. The IRD albedo dosemeter used in the routine neutron individual monitoring is described in detail. Its dosimetric properties and calibration methods are discussed. (Author) [pt

  20. Study of the effects of radon in three biological systems; Estudio de los efectos del radon en tres sistemas biologicos

    Energy Technology Data Exchange (ETDEWEB)

    Tavera, L. [Instituto Mexicano del Petroleo, Av. Eje Central Lazaro Cardenas No. 152, Edif. 23, Col. San Mateo Atepehuacan, 07730 Mexico D.F. (Mexico); Balcazar, M.; Lopez, A.; Brena, M. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Rosa, M.E. De la [Facultad de Quimica, UNAM, 04510 Mexico D.F. (Mexico); Villalobos P, R. [Centro de Estudios de la Atmosfera, UNAM, 04510 Mexico D.F. (Mexico)

    2002-07-01

    The radon and its decay products are responsible of the 3/4 parts of the exposure of the persons to the environmental radiation. The discovery at the end of XIX Century of the illnesses, mainly of cancer, which appeared in the presence of radon, lead to an accelerated growing of the radon studies: monitoring, dosimetry, effects on the persons, etc. Several epidemiological studies of radon in miners and population in general have been realized; advancing in the knowledge about the concentration-lung cancer risk relationship, but with discrepancies in the results depending on the concentration levels. Therefor, studies which consuming time, efforts and money go on doing. The research of the radon effects in biological systems different to human, allows to realize studies in less time, in controlled conditions and generally at lower cost, generating information about the alpha radiation effects in the cellular field. Therefor it was decided to study the response of three biological systems exposed to radon: an unicellular bacteria Escherichia Coli which was exposed directly to alpha particles from an electrodeposited source for determining the sensitivity limit of the chose technique. A plant, Tradescantia, for studying the cytogenetic effect of the system exposed to controlled concentrations of radon. An insect, Drosophila Melanogaster, for studying the genetic effects and the accumulated effects in several generations exposed to radon. In this work the experimental settlements are presented for the expositions of the systems and the biological results commenting the importance of these. (Author)

  1. JENDL Dosimetry File

    International Nuclear Information System (INIS)

    Nakazawa, Masaharu; Iguchi, Tetsuo; Kobayashi, Katsuhei; Iwasaki, Shin; Sakurai, Kiyoshi; Ikeda, Yujiro; Nakagawa, Tsuneo.

    1992-03-01

    The JENDL Dosimetry File based on JENDL-3 was compiled and integral tests of cross section data were performed by the Dosimetry Integral Test Working Group of the Japanese Nuclear Data Committee. Data stored in the JENDL Dosimetry File are the cross sections and their covariance data for 61 reactions. The cross sections were mainly taken from JENDL-3 and the covariances from IRDF-85. For some reactions, data were adopted from other evaluated data files. The data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-5 format. In order to confirm reliability of the data, several integral tests were carried out; comparison with the data in IRDF-85 and average cross sections measured in fission neutron fields, fast reactor spectra, DT neutron fields and Li(d, n) neutron fields. As a result, it has been found that the JENDL Dosimetry File gives better results than IRDF-85 but there are some problems to be improved in future. The contents of the JENDL Dosimetry File and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form. (author) 76 refs

  2. Dosimetry and Calibration Section

    International Nuclear Information System (INIS)

    Otto, T.

    1999-01-01

    The Dosimetry and Calibration Section fulfils two tasks within CERN's Radiation Protection Group: the Individual Dosimetry Service monitors more than 5000 persons potentially exposed to ionizing radiation on the CERN sites, and the Calibration Laboratory verifies throughout the year, at regular intervals, over 1000 instruments, monitors, and electronic dosimeters used by RP Group. The establishment of a Quality Assurance System for the Individual Dosimetry Service, a requirement of the new Swiss Ordinance for personal dosimetry, put a considerable workload on the section. Together with an external consultant it was decided to identify and then describe the different 'processes' of the routine work performed in the dosimetry service. The resulting Quality Manual was submitted to the Federal Office for Public Health in Bern in autumn. The CERN Individual Dosimetry Service will eventually be officially endorsed after a successful technical test in March 1999. On the technical side, the introduction of an automatic development machine for gamma films was very successful. It processes the dosimetric films without an operator being present, and its built-in regeneration mechanism keeps the concentration of the processing chemicals at a constant level

  3. JENDL Dosimetry File

    Energy Technology Data Exchange (ETDEWEB)

    Nakazawa, Masaharu; Iguchi, Tetsuo [Tokyo Univ. (Japan). Faculty of Engineering; Kobayashi, Katsuhei [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Inst.; Iwasaki, Shin [Tohoku Univ., Sendai (Japan). Faculty of Engineering; Sakurai, Kiyoshi; Ikeda, Yujior; Nakagawa, Tsuneo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1992-03-15

    The JENDL Dosimetry File based on JENDL-3 was compiled and integral tests of cross section data were performed by the Dosimetry Integral Test Working Group of the Japanese Nuclear Data Committee. Data stored in the JENDL Dosimetry File are the cross sections and their covariance data for 61 reactions. The cross sections were mainly taken from JENDL-3 and the covariances from IRDF-85. For some reactions, data were adopted from other evaluated data files. The data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-5 format. In order to confirm reliability of the data, several integral tests were carried out; comparison with the data in IRDF-85 and average cross sections measured in fission neutron fields, fast reactor spectra, DT neutron fields and Li(d,n) neutron fields. As a result, it has been found that the JENDL Dosimetry File gives better results than IRDF-85 but there are some problems to be improved in future. The contents of the JENDL Dosimetry File and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form.

  4. Computerised modelling for developmental biology : an exploration with case studies

    NARCIS (Netherlands)

    Bertens, Laura M.F.

    2012-01-01

    Many studies in developmental biology rely on the construction and analysis of models. This research presents a broad view of modelling approaches for developmental biology, with a focus on computational methods. An overview of modelling techniques is given, followed by several case studies. Using

  5. Dosimetry of internal emitting: principles and perspectives of the MIRD technology; Dosimetria de emisores internos: principios y perspectivas de la metodologia MIRD

    Energy Technology Data Exchange (ETDEWEB)

    Ferro F, G [Gerencia de Aplicaciones Nucleares en la Salud, Instituto Nacional de Investigaciones Nucleares, Salazar, Estado de Mexico C.P. 52045 (Mexico)

    1999-07-01

    The development of the radiopharmaceutical technology have multiplied the number of radioisotopes with applications in therapeutical nuclear medicine so known as Directed radiotherapy. Assuming the radiation is capable to produce noxious effects in the biological systems, it is important to evaluate appropriately the risks and benefits of the administration of radioactive agents in the patient. The outstanding parameter in this evaluation is the absorbed dose, which is product of the radiation emitted by a radionuclide that is localized or distributed to the interior of the human body in study and whose its estimation helps to predict the efficacy of the treatment. The scheme generalized of MIRD, it was formulated from thirty years ago for evaluating the interior dosimetry at level of organs.The finality of this work is to show the basic principles of the MIRD methodology and its perspectives using innovator tools as the dosimetry for dynamic masses, in particular the personnel dosimetry for the organs of each patient, the dosimetry for the small structures inside the organs (sub organic dosimetry), the distributions of doses in three dimensions (S voxel), the dosimetry at cellular level and the quantitative acquisition of pharmaceutical data. (Author)

  6. Dosimetry and Image Quality in Control Studies in Computerised Tomography Realized to Paediatric Patients

    International Nuclear Information System (INIS)

    Hernandez, M. R.; Gamboa-deBuen, I.; Dies, P.; Rickards, J.; Ruiz, C.

    2008-01-01

    Computerised tomography (CT) is a favourite method of medical diagnosis. Its use has thus increased rapidly throughout the world, particularly in studies relating to children. However to avoid administering unnecessarily high doses of radiation to paediatric patients it is important to have correct dose reference levels to minimize risk. The research is being developed within the public health sector at the Hospital Infantil de Mexico ''Dr. Federico Gomez.'' We measured the entrance surface air kerma (K P ) in paediatric patients, during the radiological studies of control in CT (studies of head, thorax and abdomen). Phantom was used to evaluate image quality as the tomograph requires a high resolution image in order to operate at its optimum level

  7. Pilot study: relative dose of the TLD, OSL and Radiochromic film applied in CT exams dosimetry

    International Nuclear Information System (INIS)

    Kikuti, C.F.; Maia, R.S.I.; Romano, R.F.T.; Daros, K. A.C.

    2015-01-01

    At DDI/UNIFESP, the abdomen and chest CT exams correspond to 38% of the exams, becoming the focus of studies. The aim of this study is to assess the relative dose using TLDs, OSLs and RF for the evaluation of the dose distribution in the skin in abdomen CT exams. The simulation of the CT exam was performed in an anthropomorphic phantom, using a CT scanner Philips, Brilliance/64 and TLDs, OSLs and RF fixed along the sagittal axis of the phantom. The OSLs showed similar performance to the TLDs and RF shows low accuracy, resulting in an average value (0.927±0.022). (author)

  8. Pilot study: relative dose of the TLD, OSL and Radiochromic film applied in CT exams dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kikuti, C.F. [Universidade Federal do Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Hospital Universitario Maria Aparecida Pedrossian; Maia, R.S.I.; Romano, R.F.T.; D