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Sample records for calculate external radiation

  1. Calculation of conversion coefficients for radiological protection against external radiation exposures

    International Nuclear Information System (INIS)

    Zankl, M.

    2001-01-01

    Calculations are essential for radiation protection practice because organ doses and effective doses cannot be measured directly. Conversion coefficients describe the numerical relationships of protection quantities and operational quantities. The latter can be measured in practical situations using suitable dosimeters. The conversion coefficients are calculated using radiation transport codes - usually based on Monte Carlo methods - that simulate the interactions of radiation with matter in computational models of the human body. A new generation of human body models, the so-called voxel models, are constructed from image data of real persons using suitable image processing systems, consequently, they represent the human anatomy more realistically than the so-called mathematical models. The numerical effects of realistic body anatomy on the calculated conversion coefficients can amount to 70% and more for external exposures. (orig.) [de

  2. Basis for calculating body equivalent doses after external radiation exposure. 3. rev. and enl. ed.; Berechnungsgrundlage fuer die Ermittlung von Koerper-Aequivalentdosen bei aeusserer Strahlenexposition

    Energy Technology Data Exchange (ETDEWEB)

    Sarenio, O. (comp.) [Geschaeftsstelle der Strahlenschutzkommission beim Bundesamt fuer Strahlenschutz, Bonn (Germany)

    2017-07-01

    The book on the basis for calculating body equivalent doses after external radiation exposure includes the following issues: introduction covering the scope of coverage and body equivalent doses for radiation protection, terminology, photon radiation, neutron radiation, electron radiation, mixed radiation fields and the estimation of body equivalent doses for skin surface contamination.

  3. External radiation surveillance

    International Nuclear Information System (INIS)

    Antonio, E.J.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site

  4. External radiation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site.

  5. Summary and recommendations of a National Cancer Institute workshop on issues limiting the clinical use of Monte Carlo dose calculation algorithms for megavoltage external beam radiation therapy

    International Nuclear Information System (INIS)

    Fraass, Benedick A.; Smathers, James; Deye, James

    2003-01-01

    Due to the significant interest in Monte Carlo dose calculations for external beam megavoltage radiation therapy from both the research and commercial communities, a workshop was held in October 2001 to assess the status of this computational method with regard to use for clinical treatment planning. The Radiation Research Program of the National Cancer Institute, in conjunction with the Nuclear Data and Analysis Group at the Oak Ridge National Laboratory, gathered a group of experts in clinical radiation therapy treatment planning and Monte Carlo dose calculations, and examined issues involved in clinical implementation of Monte Carlo dose calculation methods in clinical radiotherapy. The workshop examined the current status of Monte Carlo algorithms, the rationale for using Monte Carlo, algorithmic concerns, clinical issues, and verification methodologies. Based on these discussions, the workshop developed recommendations for future NCI-funded research and development efforts. This paper briefly summarizes the issues presented at the workshop and the recommendations developed by the group

  6. Control of external radiation exposure

    International Nuclear Information System (INIS)

    Abd Nasir Ibrahim; Azali Muhammad; Ab Razak Hamzah; Abd Aziz Mohamed; Mohammad Pauzi Ismail

    2004-01-01

    The following subjects are discussed - Control of external radiation exposure: working time, working distance, shielding: Total Linear Attenuation Coefficient, Half-Value Layer (HVL), Tenth-Value Layer (TVL); Build-up Factor

  7. Dosimetric quality control of treatment planning systems in external radiation therapy using Digital Test Objects calculated by PENELOPE Monte-Carlo simulations

    International Nuclear Information System (INIS)

    Ben Hdech, Yassine

    2011-01-01

    To ensure the required accuracy and prevent from mis-administration, cancer treatments, by external radiation therapy are simulated on Treatment Planning System or TPS before radiation delivery in order to ensure that the prescription is achieved both in terms of target volumes coverage and healthy tissues protection. The TPS calculates the patient dose distribution and the treatment time per beam required to deliver the prescribed dose. TPS is a key system in the decision process of treatment by radiation therapy. It is therefore essential that the TPS be subject to a thorough check of its performance (quality control or QC) and in particular its ability to accurately compute dose distributions for patients in all clinical situations that be met. The 'traditional' methods recommended to carry out dosimetric CQ of algorithms implemented in the TPS are based on comparisons between dose distributions calculated with the TPS and dose measured in physical test objects (PTO) using the treatment machine. In this thesis we propose to substitute the reference dosimetric measurements performed in OTP by benchmark dose calculations in Digital Test Objects using PENELOPE Monte-Carlo code. This method has three advantages: (i) it allows simulation in situations close to the clinic and often too complex to be experimentally feasible; (ii) due to the digital form of reference data the QC process may be automated; (iii) it allows a comprehensive TPS CQ without hindering the use of an equipment devoted primarily to patients treatments. This new method of CQ has been tested successfully on the Eclipse TPS from Varian Medical Systems Company. (author) [fr

  8. External radiation carcinogenesis

    International Nuclear Information System (INIS)

    Fry, R.J.M.; Storer, J.B.

    1987-01-01

    There have been many reviews of the subject of radiation carcinogenesis in general and of specific radiation-induced cancers. The aim of this article is not to give an exhaustive, and perhaps exhausting, review of all that has been published since the thorough treatise of Walburg in volume 4 of this series but rather to concentrate on the questions that still remain of importance and recent contributions to the answers. In the years since 1974 a vast amount of information has been reported, and the authors assess what gain there has been in knowledge. For example, it is in the 13 years since the last review that the great majority of data for the carcinogenic effects of neutrons has appeared. It is over 50 years since the discovery of the neutron, and yet knowledge of the carcinogenic effects of neutrons is far from adequate

  9. External radiation exposure of the public

    International Nuclear Information System (INIS)

    Mehl, J.

    1977-01-01

    Results of several ten thousand measurements on external radiation (outside buildings, in living rooms) are used for illustrating by isodose charts covering the total area of the Federal Republic of Germany the exposure of the public from external radiation originating from natural radiation of the environment. Results of calculations on external radiation exposure of the public due to releases of radioactivity in air from nuclear installations are used for illustrating by coloured isodose charts the exposure of the public in the plant site vicinity. From comparison of the exposure levels it becomes obvious that if exposure levels of several 10 mrem per year are considered to be of real concern to public health, control of natural radoactivity in the environment of man would require more attention than present and foreseeable releases of radioactivity in air from nuclear inst

  10. Applied physics of external radiation exposure dosimetry and radiation protection

    CERN Document Server

    Antoni, Rodolphe

    2017-01-01

    This book describes the interaction of living matter with photons, neutrons, charged particles, electrons and ions. The authors are specialists in the field of radiation protection. The book synthesizes many years of experiments with external radiation exposure in the fields of dosimetry and radiation shielding in medical, industrial and research fields. It presents the basic physical concepts including dosimetry and offers a number of tools to be used by students, engineers and technicians to assess the radiological risk and the means to avoid them by calculating the appropriate shields. The theory of radiation interaction in matter is presented together with empirical formulas and abacus. Numerous numerical applications are treated to illustrate the different topics. The state of the art in radiation protection and dosimetry is presented in detail, especially in the field of simulation codes for external exposure to radiation, medical projects and advanced research. Moreover, important data spread in differ...

  11. Results of calculations of external gamma radiation exposure rates from fallout and the related radionuclide compositions. Operation Tumbler-Snapper, 1952

    International Nuclear Information System (INIS)

    Hicks, H.G.

    1981-07-01

    This report presents data on calculated gamma radiation exposure rates and ground deposition of related radionuclides resulting from Events that deposited detectable radioactivity outside the Nevada Test Site complex

  12. Results of calculations of external gamma radiation exposure rates from local fallout and the related radionuclide compositions of two hypothetical 1-MT nuclear bursts. Final report

    International Nuclear Information System (INIS)

    Hicks, H.

    1984-12-01

    This report presents data on calculated gamma radiation exposure rates and local surface deposition of related radionuclides resulting from two hypothetical 1-Mt nuclear bursts. Calculations are made of the debris from two types of bombs: one containing 235 U as a fissionable material (designated oralloy), the other containing 238 U (designated tuballoy). 4 references

  13. 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

  14. External Beam Radiation Therapy for Cancer

    Science.gov (United States)

    External beam radiation therapy is used to treat many types of cancer. it is a local treatment, where a machine aims radiation at your cancer. Learn more about different types of external beam radiation therapy, and what to expect if you're receiving treatment.

  15. Risk analysis of external radiation therapy

    International Nuclear Information System (INIS)

    Arvidsson, Marcus

    2011-09-01

    External radiation therapy is carried out via a complex treatment process in which many different groups of staff work together. Much of the work is dependent on and in collaboration with advanced technical equipment. The purpose of the research task has been to identify a process for external radiation therapy and to identify, test and analyze a suitable method for performing risk analysis of external radiation therapy

  16. Evaluation of the external radiation exposure dosimetry and calculation of maximum permissible concentration values for airborne materials containing 18F, 15O, 13N, 11C and 133Xe

    International Nuclear Information System (INIS)

    Piltingsrud, H.V.; Gels, G.L.

    1985-01-01

    To better understand the dose equivalent (D.E.) rates produced by airborne releases of gaseous positron-emitting radionuclides under various conditions of cloud size, a study of the external radiation exposure dosimetry of these radionuclides, as well as negatron, gamma and x-ray emitting 133Xe, was undertaken. This included a calculation of the contributions to D.E. as a function of cloud radii, at tissue depths of 0.07 mm (skin), 3 mm (lens of eye) and 10 mm (whole body) from both the particulate and photon radiations emitted by these radionuclides. Estimates of maximum permissible concentration (MPC) values were also calculated based on the calculated D.E. rates and current regulations for personnel radiation protection (CFR84). Three continuous air monitors, designed for use with 133Xe, were evaluated for applications in monitoring air concentrations of the selected positron emitters. The results indicate that for a given radionuclide and for a cloud greater than a certain radius, personnel radiation dosimeters must respond acceptably to only the photon radiations emitted by the radionuclide to provide acceptable personnel dosimetry. For clouds under that radius, personnel radiation dosimeters must also respond acceptably to the positron or negatron radiations to provide acceptable personnel dosimetry. It was found that two out of the three air concentration monitors may be useful for monitoring air concentrations of the selected positron emitters

  17. External radiation exposure after deposition of man-made radionuclides

    International Nuclear Information System (INIS)

    Jacob, P.

    1991-01-01

    The first step in assessing the external radiation exposure of the population is the determination of the gamma dose rate over meadows, which are used as reference points for various reasons. The second step is the description of external radiation exposures in urban and rural environments. The relation to the radiation exposure in a meadow is a function of the radionuclide distribution, i.e. the type of deposition. Finally, a simple method of calculating external radiation exposure is developed on the basis of recent findings. The method is compared with the method used in the UNSCEAR report for calculating radiation exposures after Chernobyl and with the method described in the AVV (General Administrative Regulation) of the Radiation Protection Ordinance. (orig./HP) [de

  18. Building Protection Against External Ionizing Fallout Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Homann, Steven G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-01

    A nuclear explosion has the potential to injure or kill tens to hundreds of thousands of people through exposure to fallout (external gamma) radiation. Existing buildings can protect their occupants (reducing external radiation exposures) by placing material and distance between fallout particles and indoor individuals. This protection is not well captured in current fallout risk assessment models and so the US Department of Defense is implementing the Regional Shelter Analysis methodology to improve the ability of the Hazard Prediction and Assessment Capability (HPAC) model to account for building protection. This report supports the HPAC improvement effort by identifying a set of building attributes (next page) that, when collectively specified, are sufficient to calculate reasonably accurate, i.e., within a factor of 2, fallout shelter quality estimates for many individual buildings. The set of building attributes were determined by first identifying the key physics controlling building protection from fallout radiation and then assessing which building attributes are relevant to the identified physics. This approach was evaluated by developing a screening model (PFscreen) based on the identified physics and comparing the screening model results against the set of existing independent experimental, theoretical, and modeled building protection estimates. In the interests of transparency, we have developed a benchmark dataset containing (a) most of the relevant primary experimental data published by prior generations of fallout protection scientists as well as (b) the screening model results.

  19. Calculating radiation exposure and dose

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    This paper discusses the methods and procedures used to calculate the radiation exposures and radiation doses to designated employees of the Olympic Dam Project. Each of the three major exposure pathways are examined. These are: gamma irradiation, radon daughter inhalation and radioactive dust inhalation. A further section presents ICRP methodology for combining individual pathway exposures to give a total dose figure. Computer programs used for calculations and data storage are also presented briefly

  20. Prenatal radiation exposure. Dose calculation

    International Nuclear Information System (INIS)

    Scharwaechter, C.; Schwartz, C.A.; Haage, P.; Roeser, A.

    2015-01-01

    The unborn child requires special protection. In this context, the indication for an X-ray examination is to be checked critically. If thereupon radiation of the lower abdomen including the uterus cannot be avoided, the examination should be postponed until the end of pregnancy or alternative examination techniques should be considered. Under certain circumstances, either accidental or in unavoidable cases after a thorough risk assessment, radiation exposure of the unborn may take place. In some of these cases an expert radiation hygiene consultation may be required. This consultation should comprise the expected risks for the unborn while not perturbing the mother or the involved medical staff. For the risk assessment in case of an in-utero X-ray exposition deterministic damages with a defined threshold dose are distinguished from stochastic damages without a definable threshold dose. The occurrence of deterministic damages depends on the dose and the developmental stage of the unborn at the time of radiation. To calculate the risks of an in-utero radiation exposure a three-stage concept is commonly applied. Depending on the amount of radiation, the radiation dose is either estimated, roughly calculated using standard tables or, in critical cases, accurately calculated based on the individual event. The complexity of the calculation thereby increases from stage to stage. An estimation based on stage one is easily feasible whereas calculations based on stages two and especially three are more complex and often necessitate execution by specialists. This article demonstrates in detail the risks for the unborn child pertaining to its developmental phase and explains the three-stage concept as an evaluation scheme. It should be noted, that all risk estimations are subject to considerable uncertainties.

  1. A Methodology Proposal to Calculate the Externalities of Liquid Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Galan, A.; Gonzalez, R.; Varela, M. [Ciemat. Madrid (Spain)

    1999-05-01

    The aim of the survey is to propose a methodology to calculate the externalities associated with the liquid bio fuels cycle. The report defines the externalities from a theoretical point of view and classifies them. The reasons to value the externalities are explained as well as the existing methods. Furthermore, an evaluation of specific environmental and non-environmental externalities is also presented. The report reviews the current situation of the transport sector, considering its environmental effects and impacts. The progress made by the ExternE and ExternE-transport projects related the externalities of transport sector is assessed. Finally, the report analyses the existence of different economic instruments to internalize the external effects of the transport sector as well as other aspects of this internalization. (Author) 58 refs.

  2. Calculations in external fields in quantum chromodynamics

    International Nuclear Information System (INIS)

    Novikov, V.A.; Shifman, M.A.; Vairshtejn, A.I.; Zakharov, V.I.

    1983-01-01

    The technique of calculation of operator expansion coefficients is reviewed. The main emphasis is put on gluon operators which appear in expansion of n-point functions induced by colourless quark currents. Two convenient schemes are discussed in detail: the abstract operator method and the method based on the Fock-Schwinger gauge for the vacuum gluon field. A large number of instructive examples important from the point of view of physical applications is considered

  3. Engineering calculations in radiative heat transfer

    CERN Document Server

    Gray, W A; Hopkins, D W

    1974-01-01

    Engineering Calculations in Radiative Heat Transfer is a six-chapter book that first explains the basic principles of thermal radiation and direct radiative transfer. Total exchange of radiation within an enclosure containing an absorbing or non-absorbing medium is then described. Subsequent chapters detail the radiative heat transfer applications and measurement of radiation and temperature.

  4. Thyroid abnormalities after therapeutic external radiation

    International Nuclear Information System (INIS)

    Hancock, Steven L.; McDougall, I. Ross; Constine, Louis S.

    1995-01-01

    The thyroid gland is the largest pure endocrine gland in the body and one of the organs most likely to produce clinically significant abnormalities after therapeutic external radiation. Radiation doses to the thyroid that exceed approximately 26 Gy frequently produce hypothyroidism, which may be clinically overt or subclinical, as manifested by increased serum thyrotropin and normal serum-free thyroxine concentrations. Pituitary or hypothalamic hypothyroidism may arise when the pituitary region receives doses exceeding 50 Gy with conventional, 1.8-2 Gy fractionation. Direct irradiation of the thyroid may increase the risk of Graves' disease or euthyroid Graves' opthalmopathy. Silent thyroiditis, cystic degeneration, benign adenoma, and thyroid cancer have been observed after therapeutically relevant doses of external radiation. Direct or incidental thyroid irradiation increases the risk for well-differentiated, papillary, and follicular thyroid cancer from 15- to 53-fold. Thyroid cancer risk is highest following radiation at a young age, decreases with increasing age at treatment, and increases with follow-up duration. The potentially prolonged latent period between radiation exposure and the development of thyroid dysfunction, thyroid nodularity, and thyroid cancer means that individuals who have received neck or pituitary irradiation require careful, periodic clinical and laboratory evaluation to avoid excess morbidity

  5. Thyroid abnormalities after therapeutic external radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hancock, S.L.; McDougall, I.R. [Stanford Univ. School of Medicine, Stanford, CA (United States); Constine, L.S. [Strong Memorial Hospital, Rochester, NY (United States)

    1995-03-30

    The thyroid gland is the largest pure endocrine gland in the body and one of the organs most likely to produce clinically significant abnormalities after therapeutic external radiation. Radiation doses to the thyroid that exceed approximately 26 Gy frequently produce hypothyroidism, which may be clinically overt or subclinical, as manifested by increased serum thyrotropin and normal serum-free thyroxine concentrations. Pituitary or hypothalamic hypothyroidism may arise when the pituitary region receives doses exceeding 50 Gy with conventional, 1.8-2 Gy fractionation. Direct irradiation of the thyroid may increase the risk of Graves` disease or euthyroid Graves` ophthalmopathy. Silent thyroiditis, cystic degeneration, benign adenoma, and thyroid cancer have been observed after therapeutically relevant doses of external radiation. Direct or incidental thyroid irradiation increases the risk for well-differentiated, papillary, and follicular thyroid cancer from 15- to 53-fold. Thyroid cancer risk is highest following radiation at a young age, decreases with increasing age at treatment, and increases with follow-up duration. The potentially prolonged latent period between radiation exposure and the development of thyroid dysfunction, thyroid nodularity, and thyroid cancer means that individuals who have received neck or pituitary irradiation require careful, periodic clinical and laboratory evaluation to avoid excess morbidity. 39 refs.

  6. Simulation and radiation treatment in external radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Singer, E [Mevaterapia Medical Center, Buenos Aires (Argentina)

    1996-08-01

    It is well known that in order to obtain a uniform dose in the treated volume as defined in ICRU 50, there should be a 10% maximum difference between maximum and minimum dose values in treatment planning. Clinical target volume (CTV) should be related to external areas of body sections where tumour is located. These areas are important because different radiation beams enter through them. Therefore, verification of the planning target volume (PTV) through the external areas is highly significant. In this work we point out the importance of controlling that PTV is irradiated as planned considering some error sources usually found in radiotherapy practice with equipment that has been intensively used for a long time. Moreover, I think this experience will be helpful for those centers around the world where radiation treatment is carried out with reconditioned units. (author).

  7. Simulation and radiation treatment in external radiotherapy

    International Nuclear Information System (INIS)

    Singer, E.

    1996-01-01

    It is well known that in order to obtain a uniform dose in the treated volume as defined in ICRU 50, there should be a 10% maximum difference between maximum and minimum dose values in treatment planning. Clinical target volume (CTV) should be related to external areas of body sections where tumour is located. These areas are important because different radiation beams enter through them. Therefore, verification of the planning target volume (PTV) through the external areas is highly significant. In this work we point out the importance of controlling that PTV is irradiated as planned considering some error sources usually found in radiotherapy practice with equipment that has been intensively used for a long time. Moreover, I think this experience will be helpful for those centers around the world where radiation treatment is carried out with reconditioned units. (author)

  8. Calculation of freight externality costs for South Africa

    Directory of Open Access Journals (Sweden)

    Stefaan Swarts

    2012-11-01

    Full Text Available The purpose of this study is to quantify the marginal external costs associated with freight transport in South Africa. Six cost elements are included as externality cost items, namely, costs related to accidents, emissions, roadway land availability, policing, noise and congestion. Inputs in the calculations were a gravity-oriented freight flow model, a road transport cost model, actual transport costs for other modes, a warehousing cost survey, an inventory delay calculation and various national sources of information such as accident statistics and government budgets. Estimation techniques resulted in advances for externality cost measurement in South Africa. The quantification of the cost elements will be used to update the South African Freight Demand Model. The results show that the cost of transportation would have been 20% more if external factors were taken into account. The marginal rates of externalities can be used to develop scenarios based on alternative choices for South Africa's freight transport infrastructure configuration.

  9. Study on external beam radiation therapy

    International Nuclear Information System (INIS)

    Kim, Mi Sook; Yoo, Seoung Yul; Yoo, Hyung Jun; Ji, Young Hoon; Lee, Dong Han; Lee, Dong Hoon; Choi, Mun Sik; Yoo, Dae Heon; Lee, Hyo Nam; Kim, Kyeoung Jung

    1999-04-01

    To develop the therapy technique which promote accuracy and convenience in external radiation therapy, to obtain the development of clinical treatment methods for the global competition. The contents of the R and D were 1. structure, process and outcome analysis in radiation therapy department. 2. Development of multimodality treatment in radiation therapy 3. Development of computation using networking techniques 4. Development of quality assurance (QA) system in radiation therapy 5. Development of radiotherapy tools 6. Development of intraoperative radiation therapy (IORT) tools. The results of the R and D were 1. completion of survey and analysis about Korea radiation therapy status 2. Performing QA analysis about ICR on cervix cancer 3. Trial of multicenter randomized study on lung cancers 4. Setting up inter-departmental LAN using MS NT server and Notes program 5. Development of ionization chamber and dose-rate meter for QA in linear accelerator 6. Development on optimized radiation distribution algorithm for multiple slice 7. Implementation on 3 dimensional volume surface algorithm and 8. Implementation on adaptor and cone for IORT

  10. Study on external beam radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mi Sook; Yoo, Seoung Yul; Yoo, Hyung Jun; Ji, Young Hoon; Lee, Dong Han; Lee, Dong Hoon; Choi, Mun Sik; Yoo, Dae Heon; Lee, Hyo Nam; Kim, Kyeoung Jung

    1999-04-01

    To develop the therapy technique which promote accuracy and convenience in external radiation therapy, to obtain the development of clinical treatment methods for the global competition. The contents of the R and D were 1. structure, process and outcome analysis in radiation therapy department. 2. Development of multimodality treatment in radiation therapy 3. Development of computation using networking techniques 4. Development of quality assurance (QA) system in radiation therapy 5. Development of radiotherapy tools 6. Development of intraoperative radiation therapy (IORT) tools. The results of the R and D were 1. completion of survey and analysis about Korea radiation therapy status 2. Performing QA analysis about ICR on cervix cancer 3. Trial of multicenter randomized study on lung cancers 4. Setting up inter-departmental LAN using MS NT server and Notes program 5. Development of ionization chamber and dose-rate meter for QA in linear accelerator 6. Development on optimized radiation distribution algorithm for multiple slice 7. Implementation on 3 dimensional volume surface algorithm and 8. Implementation on adaptor and cone for IORT.

  11. Quality control of the treatment planning systems dose calculations in external radiation therapy using the Penelope Monte Carlo code; Controle qualite des systemes de planification dosimetrique des traitements en radiotherapie externe au moyen du code Monte-Carlo Penelope

    Energy Technology Data Exchange (ETDEWEB)

    Blazy-Aubignac, L

    2007-09-15

    The treatment planning systems (T.P.S.) occupy a key position in the radiotherapy service: they realize the projected calculation of the dose distribution and the treatment duration. Traditionally, the quality control of the calculated distribution doses relies on their comparisons with dose distributions measured under the device of treatment. This thesis proposes to substitute these dosimetry measures to the profile of reference dosimetry calculations got by the Penelope Monte-Carlo code. The Monte-Carlo simulations give a broad choice of test configurations and allow to envisage a quality control of dosimetry aspects of T.P.S. without monopolizing the treatment devices. This quality control, based on the Monte-Carlo simulations has been tested on a clinical T.P.S. and has allowed to simplify the quality procedures of the T.P.S.. This quality control, in depth, more precise and simpler to implement could be generalized to every center of radiotherapy. (N.C.)

  12. The assessment of personal dose due to external radiation

    International Nuclear Information System (INIS)

    Boas, J.F.; Young, J.G.

    1990-01-01

    The fundamental basis of thermoluminescent dosimetry (TLD) is discussed and a number of considerations in the measurement of thermoluminescence described, with particular reference to CaSO 4 :Dy. The steps taken to convert a thermoluminescence measurement to an exposure and then an absorbed dose are outlined. The calculation of effective dose equivalents due to external exposure to γ-radiation in a number of situations commonly encountered in a uranium mine is discussed. Factors which may affect the accuracy of external dose assessments are described

  13. Influence of external source location in the reactivity calculation

    International Nuclear Information System (INIS)

    Silva, Adilson Costa da; Silva, Fernando Carvalho da; Martinez, Aquilino Senra

    2011-01-01

    We used the neutron diffusion equation with external neutron sources, in cartesian geometry and the two groups of energy, to verify the influence of external neutron source locations in the reactivity calculation. For this, a coarse mesh finite difference method was developed for the adjoint flux calculation and simplifies reactivity calculation in PWR type reactor, which uses the output of the nodal expansion method. The results were obtained for different locations on the two-dimensional plane, as well as for different types of fuel elements in the reactor core. (author)

  14. Influence of external source location in the reactivity calculation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adilson Costa da; Silva, Fernando Carvalho da; Martinez, Aquilino Senra, E-mail: asilva@con.ufrj.b, E-mail: fernando@con.ufrj.b, E-mail: Aquilino@lmp.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2011-07-01

    We used the neutron diffusion equation with external neutron sources, in cartesian geometry and the two groups of energy, to verify the influence of external neutron source locations in the reactivity calculation. For this, a coarse mesh finite difference method was developed for the adjoint flux calculation and simplifies reactivity calculation in PWR type reactor, which uses the output of the nodal expansion method. The results were obtained for different locations on the two-dimensional plane, as well as for different types of fuel elements in the reactor core. (author)

  15. Environmental external radiation at some Bulgarian localities

    International Nuclear Information System (INIS)

    Spurny, F.; Turek, K.; Gelev, M.

    2004-01-01

    Studies of the environmental radiation background are important from several points of view. First, they permit to estimate the exposure of humans to natural radiation background as a function of different geographical and geophysical parameters. Second, such studies can give also relevant information concerning the consequences of human activities on the presence of ionizing radiation and its sources in the environment. Our both institutions have started since 2000 year common studies in the field of environmental radiation background and its variation with the locality considered. First we have decided to compare the measuring methods used. They were compared on the territory of the Institute of Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences (INRNE BAS), particularly in the surroundings of IRT 2000 research reactor. Further, they were compared also at the monitoring station on the territory of INRNE BAS. Finally, the studies were enlarged to the Moussala Observatory of the Institute at Rila Mountains. Several measuring instruments were used to characterize external environmental radiation exposure: Environmental radiation dose rate meter NB 3201 developed in the Czech Republic with a plastic scintillator with small NaI-TL crystal used to compensate the energy dependence to low energy photons; MDU-Liulin semiconductor spectrometer with Si-diode as the sensitive element able to characterize the radiation with both low and high LET; Thermoluminescent detectors (TLD) CaSO 4 :Dy, powder of this TLD material was filled to an Al dose. Results obtained are presented, analysed and discussed. A good agreement of the results obtained was observed, also when compared to the results of other experimental groups. (authors)

  16. Restenosis Prevention Using Photon External Beam Radiation

    International Nuclear Information System (INIS)

    Goldstein, M.

    2002-01-01

    During transluminal coronary angioplasty, the balloon procedure is designed to crush the plaque and to support the weakened arterial wall by using the stent (an expandable metallic mesh). This procedure often tears the arterial wall as well. Some of the cells in the blood vessel respond to this injury by initiating repair which often leads to restenosis (reclosing) of the artery. In many cases restenosis occur despite the stent which become incorporated into the poliferative tissue that form around the lesion. But if the lesion is treated with radiation (8-30 Gy) the restenosis effect is inhibited. In this paper, the Adjoint Monte Carlo (AMC) method is used for external radiation treatment planning of the stent volume (the volume covered by the stent during a full cardiac cycle), while minimizing the damage to the organs at risk (OAR) and surrounding healthy tissue

  17. Subcriticality calculation in nuclear reactors with external neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adilson Costa da; Martinez, Aquilino Senra; Silva, Fernando Carvalho da [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE). Programa de Engenharia Nuclear]. E-mails: asilva@con.ufrj.br; aquilino@lmp.ufrj.br; fernando@con.ufrj.br

    2007-07-01

    The main objective of this paper consists on the development of a methodology to monitor subcriticality. We used the inverse point kinetic equation with 6 precursor groups and external neutron sources for the calculation of reactivity. The input data for the inverse point kinetic equation was adjusted, in order to use the neutron counting rates obtained from the subcritical multiplication (1/M) in a nuclear reactor. In this paper, we assumed that the external neutron sources strength is constant and we define it in terms of a known initial condition. The results obtained from inverse point kinetic equation with external neutron sources were compared with the results obtained with a benchmark calculation, and showed good accuracy (author)

  18. Subcriticality calculation in nuclear reactors with external neutron sources

    International Nuclear Information System (INIS)

    Silva, Adilson Costa da; Martinez, Aquilino Senra; Silva, Fernando Carvalho da

    2007-01-01

    The main objective of this paper consists on the development of a methodology to monitor subcriticality. We used the inverse point kinetic equation with 6 precursor groups and external neutron sources for the calculation of reactivity. The input data for the inverse point kinetic equation was adjusted, in order to use the neutron counting rates obtained from the subcritical multiplication (1/M) in a nuclear reactor. In this paper, we assumed that the external neutron sources strength is constant and we define it in terms of a known initial condition. The results obtained from inverse point kinetic equation with external neutron sources were compared with the results obtained with a benchmark calculation, and showed good accuracy (author)

  19. Quantization of fermions in external soliton fields and index calculation

    International Nuclear Information System (INIS)

    Grosse, H.

    1986-01-01

    We review recent results on the quantization of fermions in external fields, discuss equivalent and inequivalent representations of the canonical anticommutation relations, indicate how the requirement of implementability of gauge transformations leads to quantization conditions, determine the algebra of charges, identify the Schwinger term and remark finally how one may calculate a ground state charge. (Author)

  20. Report on emergency exposure to external radiation

    International Nuclear Information System (INIS)

    Pochin, E.E.; Rock Carling, Ernest; Court Brown, W.M.

    1960-01-01

    The Medical Research Council has continued a study of the effects on the health of persons in the neighbourhood of atomic energy installations should there be a release of radioactive material as a result of fires or other incidents. The Council's Committee on Protection against Ionizing Radiations has already reported (Medical Research Council, 1959) on the maximum permissible dietary contamination for iodine 131, strontium 89, strontium 90 and caesium. 137, since it was considered that for the members of the public normally resident in the area affected ingestion of contaminated food would generally be the limiting source of hazard after any such accident and that intake by inhalation, or radiation from the exterior, would become of importance only in rather special circumstances The present report deals with the problem of exposure from the exterior, namely, from external sources of beta and gamma radiation. This exposure might be derived from two sources, one of relatively short duration from the passage of a cloud of radioactive material, the other of longer duration from deposited material

  1. Report on emergency exposure to external radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pochin, E E; Rock Carling, Ernest; Court Brown, W M [Medical Research Council, Committee on Protection against Ionizing Radiations, London (United Kingdom); and others

    1960-12-01

    The Medical Research Council has continued a study of the effects on the health of persons in the neighbourhood of atomic energy installations should there be a release of radioactive material as a result of fires or other incidents. The Council's Committee on Protection against Ionizing Radiations has already reported (Medical Research Council, 1959) on the maximum permissible dietary contamination for iodine 131, strontium 89, strontium 90 and caesium. 137, since it was considered that for the members of the public normally resident in the area affected ingestion of contaminated food would generally be the limiting source of hazard after any such accident and that intake by inhalation, or radiation from the exterior, would become of importance only in rather special circumstances The present report deals with the problem of exposure from the exterior, namely, from external sources of beta and gamma radiation. This exposure might be derived from two sources, one of relatively short duration from the passage of a cloud of radioactive material, the other of longer duration from deposited material.

  2. SCROLL, a superconfiguration collisional radiative model with external radiation

    International Nuclear Information System (INIS)

    Bar-Shalom, A.; Oreg, J.; Klapisch, M.

    2000-01-01

    A collisional radiative model for calculating non-local thermodynamical-equilibrium (non-LTE) spectra of heavy atoms in hot plasmas has been developed. It takes into account the numerous excited an autoionizing states by using superconfigurations. These are split systematically until the populations converge. The influence of an impinging radiation field has recently been added to the model. The effect can be very important. (author)

  3. Monitoring of external background radiation level in Asa dam ...

    African Journals Online (AJOL)

    An external background ionizing radiation study has been carried out within the Asa Dam Industrial Layout of Ilorin in Kwara State. The study was carried out in 5 stations within the industrial area using two Digilert Nuclear Radiation Monitors. The study has revealed that the external background ionizing radiation is ...

  4. Calculating Risk: Radiation and Chernobyl.

    Science.gov (United States)

    Gale, Robert Peter

    1987-01-01

    Considers who is at risk in a disaster such as Chernobyl. Assesses the difficulty in translating information regarding radiation to the public and in determining the acceptability of technological risks. (NKA)

  5. Calculating concentration of inhaled radiolabeled particles from external gamma counting: External counting efficiency and attenuation coefficient of thorax

    International Nuclear Information System (INIS)

    Langenback, E.G.; Foster, W.M.; Bergofsky, E.H.

    1989-01-01

    We determined the overall external counting efficiency of radiolabeled particles deposited in the sheep lung. This efficiency permits the noninvasive calculation of the number of particles and microcuries from gamma-scintillation lung images of the live sheep. Additionally, we have calculated the attenuation of gamma radiation (120 keV) by the posterior chest wall and the gamma-scintillation camera collection efficiency of radiation emitted from the lung. Four methods were employed in our experiments: (1) by light microscopic counting of discrete carbonized polystyrene particles with a count median diameter (CMD) of 2.85 microns and tagged with cobalt-57, we delineated a linear relationship between the number of particles and the emitted counts per minute (cpm) detected by well scintillation counting; (2) from this conversion relationship we determined the number of particles inhaled and deposited in the lungs by scintillation counting fragments of dissected lung at autopsy; (3) we defined a linear association between the number of particles or microcuries contained in the lung and the emitted radiation as cpm detected by a gamma scintillation camera in the live sheep prior to autopsy; and (4) we compared the emitted radiation from the lungs of the live sheep to that of whole excised lungs in order to calculate the attenuation coefficient (ac) of the chest wall. The mean external counting efficiency was 4.00 X 10(4) particles/cpm (5.1 X 10(-3) microCi/cpm), the camera collection efficiency was 1 cpm/10(4) disintegrations per minute (dpm), and the ac had a mean of 0.178/cm. The external counting efficiency remained relatively constant over a range of particles and microcuries, permitting a more general use of this ratio to estimate number of particles or microcuries depositing after inhalation in a large mammalian lung if a similarly collimated gamma camera system is used

  6. Radiation protection calculations for diagnostic medical equipment

    International Nuclear Information System (INIS)

    Klueter, R.

    1992-01-01

    The standards DIN 6812 and DIN 6844 define the radiation protection requirements to be met by biomedical radiography equipment or systems for nuclear medicine. The paper explains the use of a specific computer program for radiation protection calculations. The program offers menu-controlled calculation, with free choice of the relevant nuclides. (DG) [de

  7. Characteristics of natural background external radiation and effective dose equivalent

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1989-01-01

    The two sources of natural radiation - cosmic rays and primordial radionuclides - are described. The factors affecting radiation doses received from natural radiation and the calculation of effective dose equivalent due to natural radiation are discussed. 10 figs., 3 tabs

  8. Calculation codes in radiation protection, radiation physics and dosimetry

    International Nuclear Information System (INIS)

    2003-01-01

    These scientific days had for objective to draw up the situation of calculation codes of radiation transport, of sources estimation, of radiation doses managements and to draw the future perspectives. (N.C.)

  9. Parallel processing of dose calculation for external photon beam therapy

    International Nuclear Information System (INIS)

    Kunieda, Etsuo; Ando, Yutaka; Tsukamoto, Nobuhiro; Ito, Hisao; Kubo, Atsushi

    1994-01-01

    We implemented external photon beam dose calculation programs into a parallel processor system consisting of Transputers, 32-bit processors especially suitable for multi-processor configuration. Two network conformations, binary-tree and pipeline, were evaluated for rectangular and irregular field dose calculation algorithms. Although computation speed increased in proportion to the number of CPU, substantial overhead caused by inter-processor communication occurred when a smaller computation load was delivered to each processor. On the other hand, for irregular field calculation, which requires more computation capability for each calculation point, the communication overhead was still less even when more than 50 processors were involved. Real-time responses could be expected for more complex algorithms by increasing the number of processors. (author)

  10. Calculation of the dose caused by internal radiation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    For the purposes of monitoring radiation exposure it is necessary to determine or to estimate the dose caused by both external and internal radiation. When comparing the value of exposure to the dose limits, account must be taken of the total dose incurred from different sources. This guide explains how to calculate the committed effective dose caused by internal radiation and gives the conversion factors required for the calculation. Application of the maximum values for radiation exposure is dealt with in ST guide 7.2, which also sets out the definitions of the quantities and concepts most commonly used in the monitoring of radiation exposure. The monitoring of exposure and recording of doses are dealt with in ST Guides 7.1 and 7.4.

  11. Radiation shielding calculation using MCNP

    International Nuclear Information System (INIS)

    Masukawa, Fumihiro

    2001-01-01

    To verify the Monte Carlo code MCNP4A as a tool to generate the reference data in the shielding designs and the safety evaluations, various shielding benchmark experiments were analyzed using this code. These experiments were categorized in three types of the shielding subjects; bulk shielding, streaming, and skyshine. For the variance reduction technique, which is indispensable to get meaningful results with the Monte Carlo shielding calculation, we mainly used the weight window, the energy dependent Russian roulette and spitting. As a whole, our analyses performed enough small statistical errors and showed good agreements with these experiments. (author)

  12. SUBDOSA: a computer program for calculating external doses from accidental atmospheric releases of radionuclides

    International Nuclear Information System (INIS)

    Strenge, D.L.; Watson, E.C.; Houston, J.R.

    1975-06-01

    A computer program, SUBDOSA, was developed for calculating external γ and β doses to individuals from the accidental release of radionuclides to the atmosphere. Characteristics of SUBDOSA are: doses from both γ and β radiation are calculated as a function of depth in tissue, summed and reported as skin, eye, gonadal, and total body dose; doses are calculated for releases within each of several release time intervals and nuclide inventories and atmospheric dispersion conditions are considered for each time interval; radioactive decay is considered during the release and/or transit using a chain decay scheme with branching to account for transitions to and from isomeric states; the dose from gamma radiation is calculated using a numerical integration technique to account for the finite size of the plume; and the program computes and lists the normalized air concentrations at ground level as a function of distance from the point of release. (auth)

  13. External and internal radiation therapy: Past and future directions

    Directory of Open Access Journals (Sweden)

    Sadeghi Mahdi

    2010-01-01

    Full Text Available Cancer is a leading cause of morbidity and mortality in the modern world. Treatment modalities comprise radiation therapy, surgery, chemotherapy and hormonal therapy. Radiation therapy can be performed by using external or internal radiation therapy. However, each method has its unique properties which undertakes special role in cancer treatment, this question is brought up that: For cancer treatment, whether external radiation therapy is more efficient or internal radiation therapy one? To answer this question, we need to consider principles and structure of individual methods. In this review, principles and application of each method are considered and finally these two methods are compared with each other.

  14. The treatment progress of radiation dermatitis from external exposure

    International Nuclear Information System (INIS)

    Pu Wangyang; Liu Yulong

    2009-01-01

    Radiation dermatitis is often seen and is often a complication of radiation therapy of tumors. It is characterized by poor healing, stubborn relapse, and carcinogenesis.. The treatment include drug, physical therapy and surgery. This article describes the treatment progress of radiation dermatitis from external exposure. (authors)

  15. Anesthesia for pediatric external beam radiation therapy

    International Nuclear Information System (INIS)

    Fortney, Jennifer T.; Halperin, Edward C.; Hertz, Caryn M.; Schulman, Scott R.

    1999-01-01

    Background: For very young patients, anesthesia is often required for radiotherapy. This results in multiple exposures to anesthetic agents over a short period of time. We report a consecutive series of children anesthetized for external beam radiation therapy (EBRT). Methods: Five hundred twelve children ≤ 16 years old received EBRT from January 1983 to February 1996. Patient demographics, diagnosis, anesthesia techniques, monitoring, airway management, complications, and outcome were recorded for the patients requiring anesthesia. Results: One hundred twenty-three of the 512 children (24%) required 141 courses of EBRT with anesthesia. Anesthetized patients ranged in age from 20 days to 11 years (mean 2.6 ± 1.8 ). The frequency of a child receiving EBRT and requiring anesthesia by age cohort was: ≤ 1 year (96%), 1-2 years (93%), 2-3 years (80%), 3-4 years (51%), 4-5 years (36%), 5-6 years (13%), 6-7 years (11%), and 7-16 years (0.7%). Diagnoses included: primary CNS tumor (28%), retinoblastoma (27%), neuroblastoma (20%), acute leukemia (9%), rhabdomyosarcoma (6%), and Wilms' tumor (4%). Sixty-three percent of the patients had been exposed to chemotherapy prior to EBRT. The mean number of anesthesia sessions per patient was 22 ± 16. Seventy-eight percent of the treatment courses were once daily and 22% were twice daily. Anesthesia techniques included: short-acting barbiturate induction + inhalation maintenance (21%), inhalation only (20%), ketamine (19%), propofol only (12%), propofol induction + inhalation maintenance (7%), ketamine induction + inhalation maintenance (6%), ketamine or short-acting barbiturate induction + inhalation maintenance (6%). Monitoring techniques included: EKG (95%), O 2 saturation (93%), fraction of inspired O 2 (57%), and end-tidal CO 2 (55%). Sixty-four percent of patients had central venous access. Eleven of the 74 children with a central line developed sepsis (15%): 6 of the 11 were anesthetized with propofol (55%), 4 with a

  16. Determination of dose factors for external gamma radiation in dwellings

    International Nuclear Information System (INIS)

    Maduar, M.F.; Hiromoto, G.

    2000-01-01

    A significant contribution to the global population exposure to ionizing radiation arises from natural sources, especially from radionuclides present in terrestrial crust. Human activities can eventually increase that exposure to significant levels, from the point of view of radiological protection. The presence of natural radionuclides in building materials may lead to an increment of both external and internal radiation exposure of the population. External exposure in dwellings arises from gamma-emitter radionuclides existing in the walls, floor and ceiling of their rooms. Mathematical models can be used to predict external dose rates inside the room, known the radionuclide concentration activities in dwelling constituents. This paper presents a methodology for theoretical evaluation of external gamma doses due to radionuclides present in the walls of an hypothetical standard room. The room is modeled as three pairs of rectangular sheets with finite thickness. Assessment of doses was performed through the application of photon transport model, taking in account self-absorption and radiation buildup. As the external dose due to a particular radionuclide is proportional to its activity concentration, results are presented as dose factors, defined as a ratio of absorbed dose (nGy.h -1 ) to the activity concentration (Bq.kg -1 ), for each radionuclide. The radionuclides were assumed to be uniformly distributed in the building materials. Calculations were performed for concrete walls and results are presented for 40 K, 226 Ra, and 232 Th, taking in account, for dose calculations, all gamma emitters from 226 Ra and 232 Th decay chains. Sensitivity of the model was estimated by varying four of its input parameters within a reasonable range of applicability, while leaving all other parameters at fixed selected values. The parameters studied and respective ranges of variation were: for thickness, 5 to 60 cm; for density, 0.5 to 4 g.cm -3 ; for the room length, 1.5 to 10 m

  17. IMPORTANCE OF DELIVERY CONDITIONS IN THE EXTERNAL PRICE CALCULATION

    Directory of Open Access Journals (Sweden)

    Violeta ISAI

    2005-01-01

    Full Text Available The delivery conditions of the merchandise at export, established by the rules INCOTERMS2000, influence the external price structure. There are some conditions in which the external priceincludes only the value of the merchandise and other conditions in which, besides the value of themerchandise, the price includes also the external transport and insurance. In the case of the exportson commercial credit, when it appears the notion of external interest, this one may be included in theprice or may be invoiced separately, thus defining gross external prices and net external prices.

  18. Scattering and radiative properties of semi-external versus external mixtures of different aerosol types

    International Nuclear Information System (INIS)

    Mishchenko, Michael I.; Liu Li; Travis, Larry D.; Lacis, Andrew A.

    2004-01-01

    The superposition T-matrix method is used to compute the scattering of unpolarized light by semi-external aerosol mixtures in the form of polydisperse, randomly oriented two-particle clusters with touching components. The results are compared with those for composition-equivalent external aerosol mixtures, in which the components are widely separated and scatter light in isolation from each other. It is concluded that aggregation is likely to have a relatively weak effect on scattering and radiative properties of two-component tropospheric aerosols and can be replaced by the much simpler external-mixture model in remote sensing studies and atmospheric radiation balance computations

  19. A Methodology for Calculating Radiation Signatures

    Energy Technology Data Exchange (ETDEWEB)

    Klasky, Marc Louis [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wilcox, Trevor [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bathke, Charles G. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); James, Michael R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-01

    A rigorous formalism is presented for calculating radiation signatures from both Special Nuclear Material (SNM) as well as radiological sources. The use of MCNP6 in conjunction with CINDER/ORIGEN is described to allow for the determination of both neutron and photon leakages from objects of interest. In addition, a description of the use of MCNP6 to properly model the background neutron and photon sources is also presented. Examinations of the physics issues encountered in the modeling are investigated so as to allow for guidance in the user discerning the relevant physics to incorporate into general radiation signature calculations. Furthermore, examples are provided to assist in delineating the pertinent physics that must be accounted for. Finally, examples of detector modeling utilizing MCNP are provided along with a discussion on the generation of Receiver Operating Curves, which are the suggested means by which to determine detectability radiation signatures emanating from objects.

  20. Radiation-damage calculations with NJOY

    International Nuclear Information System (INIS)

    MacFarlane, R.E.; Muir, D.W.; Mann, F.W.

    1983-01-01

    Atomic displacement, gas production, transmutation, and nuclear heating can all be calculated with the NJOY nuclear data processing system using evaluated data in ENDF/B format. Using NJOY helps assure consistency between damage cross sections and those used for transport, and NJOY provides convenient interface formats for linking data to application codes. Unique features of the damage calculation include a simple momentum balance treatment for radiative capture and a new model for (n, particle) reactions based on statistical model calculations. Sample results for iron and nickel are given and compared with the results of other methods

  1. Spontaneous Radiation Background Calculation for LCLS

    CERN Document Server

    Reiche, Sven

    2004-01-01

    The intensity of undulator radiation, not amplified by the FEL interaction, can be larger than the maximum FEL signal in the case of an X-ray FEL. In the commissioning of a SASE FEL it is essential to extract an amplified signal early to diagnose eventual misalignment of undulator modules or errors in the undulator field strength. We developed a numerical code to calculate the radiation pattern at any position behind a multi-segmented undulator with arbitrary spacing and field profiles. The output can be run through numerical spatial and frequency filters to model the radiation beam transport and diagnostic. In this presentation we estimate the expected background signal for the FEL diagnostic and at what point along the undulator the FEL signal can be separated from the background. We also discusses how much information on the undulator field and alignment can be obtained from the incoherent radiation signal itself.

  2. Adaptation of the present concept of dosimetric radiation protection quantities for external radiation to radiation protection practice

    International Nuclear Information System (INIS)

    Boehm, J.; Thompson, I. M. G.

    2004-01-01

    The present concept of dosimetric radiation protection quantities for external radiation is reviewed. For everyday application of the concept some adaptations are recommended. The check of the compliance with dose limits should be performed either by the comparison with values of the respective operational quantities directly or by the calculation of the protection quantity by means of the operational quantity, the appertaining conversion coefficient and additional information of the radiation field. Only four operational quantities are regarded to be sufficient for most applications in radiation protection practice. The term equivalent should be used in the connection dose equivalent only. Proposals are made for names of frequently used operational quantities which are denoted up to now by symbols only. (authors)

  3. Radiative decay of coupled states in an external dc field

    International Nuclear Information System (INIS)

    Pal'chikov, V.; Sokolov, Y.; Yakovlev, V.

    2001-01-01

    This paper examines two theoretical aspects of the interference of atomic states in hydrogen which comes from the application of an external electric field F to the 2s metastable state. The radiative corrections to the Bethe-Lamb formula and anisotropy contribution to the angular distribution, which arises from interference between electric-field-induced E1-radiation and forbidden M1-radiation, are analysed

  4. Radiative decay of coupled states in an external dc field

    Energy Technology Data Exchange (ETDEWEB)

    Pal' chikov, V. [National Research Inst. for Physical-Technical and Radiotechnical Measurements (VNIIFTRI), Mendeleevo, Moscow Region (Russian Federation); Sokolov, Y. [Kurchatov Inst., Russian Research Centre, Moscow (Russian Federation); Yakovlev, V. [Moscow Engineering Physics Inst., Moscow (Russian Federation)

    2001-07-01

    This paper examines two theoretical aspects of the interference of atomic states in hydrogen which comes from the application of an external electric field F to the 2s metastable state. The radiative corrections to the Bethe-Lamb formula and anisotropy contribution to the angular distribution, which arises from interference between electric-field-induced E1-radiation and forbidden M1-radiation, are analysed.

  5. PABLM: a computer program to calculate accumulated radiation doses from radionuclides in the environment

    International Nuclear Information System (INIS)

    Napier, B.A.; Kennedy, W.E. Jr.; Soldat, J.K.

    1980-03-01

    A computer program, PABLM, was written to facilitate the calculation of internal radiation doses to man from radionuclides in food products and external radiation doses from radionuclides in the environment. This report contains details of mathematical models used and calculational procedures required to run the computer program. Radiation doses from radionuclides in the environment may be calculated from deposition on the soil or plants during an atmospheric or liquid release, or from exposure to residual radionuclides in the environment after the releases have ended. Radioactive decay is considered during the release of radionuclides, after they are deposited on the plants or ground, and during holdup of food after harvest. The radiation dose models consider several exposure pathways. Doses may be calculated for either a maximum-exposed individual or for a population group. The doses calculated are accumulated doses from continuous chronic exposure. A first-year committed dose is calculated as well as an integrated dose for a selected number of years. The equations for calculating internal radiation doses are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and MPC's of each radionuclide. The radiation doses from external exposure to contaminated water and soil are calculated using the basic assumption that the contaminated medium is large enough to be considered an infinite volume or plane relative to the range of the emitted radiations. The equations for calculations of the radiation dose from external exposure to shoreline sediments include a correction for the finite width of the contaminated beach

  6. Online external beam radiation treatment simulator

    International Nuclear Information System (INIS)

    Hamza-Lup, Felix G.; Sopin, Ivan; Zeidan, Omar

    2008-01-01

    Radiation therapy is an effective and widely accepted form of treatment for many types of cancer that requires extensive computerized planning. Unfortunately, current treatment planning systems have limited or no visual aid that combines patient volumetric models extracted from patient-specific CT data with the treatment device geometry in a 3D interactive simulation. We illustrate the potential of 3D simulation in radiation therapy with a web-based interactive system that combines novel standards and technologies. We discuss related research efforts in this area and present in detail several components of the simulator. An objective assessment of the accuracy of the simulator and a usability study prove the potential of such a system for simulation and training. (orig.)

  7. External beam radiation therapy for prostate cancer

    International Nuclear Information System (INIS)

    Forman, Jeffrey D.

    1996-01-01

    Purpose/Objectives: The intent of this course is to review the issues involved in the management of non-metastatic adenocarcinoma of the prostate. -- The value of pre-treatment prognostic factors including stage, grade and PSA value will be presented, and their value in determining therapeutic strategies will be discussed. -- Controversies involving the simulation process and treatment design will be presented. The value of CT scanning, Beams-Eye View, 3-D planning, intravesicle, intraurethral and rectal contrast will be presented. The significance of prostate and patient movement and strategies for dealing with them will be presented. -- The management of low stage, low to intermediate grade prostate cancer will be discussed. The dose, volume and timing of irradiation will be discussed as will the role of neo-adjuvant hormonal therapy, neutron irradiation and brachytherapy. The current status of radical prostatectomy and cryotherapy will be summarized. Treatment of locally advanced, poorly differentiated prostate cancer will be presented including a discussion of neo-adjuvant and adjuvant hormones, dose-escalation and neutron irradiation. -- Strategies for post-radiation failures will be presented including data on cryotherapy, salvage prostatectomy and hormonal therapy (immediate, delayed and/or intermittent). New areas for investigation will be reviewed. -- The management of patients post prostatectomy will be reviewed. Data on adjuvant radiation and therapeutic radiation for biochemical or clinically relapsed patients will be presented. This course hopes to present a realistic and pragmatic overview for treating patients with non-metastatic prostatic cancer

  8. An improved algorithm for calculating cloud radiation

    International Nuclear Information System (INIS)

    Yuan Guibin; Sun Xiaogang; Dai Jingmin

    2005-01-01

    Clouds radiation characteristic is very important in cloud scene simulation, weather forecasting, pattern recognition, and other fields. In order to detect missiles against cloud backgrounds, to enhance the fidelity of simulation, it is critical to understand a cloud's thermal radiation model. Firstly, the definition of cloud layer infrared emittance is given. Secondly, the discrimination conditions of judging a pixel of focal plane on a satellite in daytime or night time are shown and equations are given. Radiance such as reflected solar radiance, solar scattering, diffuse solar radiance, solar and thermal sky shine, solar and thermal path radiance, cloud blackbody and background radiance are taken into account. Thirdly, the computing methods of background radiance for daytime and night time are given. Through simulations and comparison, this algorithm is proved to be an effective calculating algorithm for cloud radiation

  9. Effective dose equivalents from external radiation due to Chernobyl accident

    International Nuclear Information System (INIS)

    Erkin, V.G.; Debedev, O.V.; Balonov, M.I.; Parkhomenko, V.I.

    1992-01-01

    Summarized data on measurements of individual dose of external γ-sources in 1987-1990 of population of western areas of Bryansk region were presented. Type of distribution of effective dose equivalent, its significance for various professional and social groups of population depending on the type of the house was discussed. Dependences connecting surface soil activity in the populated locality with average dose of external radiation sources were presented. Tendency of dose variation in 1987-1990 was shown

  10. Radiation transport calculation methods in BNCT

    International Nuclear Information System (INIS)

    Koivunoro, H.; Seppaelae, T.; Savolainen, S.

    2000-01-01

    Boron neutron capture therapy (BNCT) is used as a radiotherapy for malignant brain tumours. Radiation dose distribution is necessary to determine individually for each patient. Radiation transport and dose distribution calculations in BNCT are more complicated than in conventional radiotherapy. Total dose in BNCT consists of several different dose components. The most important dose component for tumour control is therapeutic boron dose D B . The other dose components are gamma dose D g , incident fast neutron dose D f ast n and nitrogen dose D N . Total dose is a weighted sum of the dose components. Calculation of neutron and photon flux is a complex problem and requires numerical methods, i.e. deterministic or stochastic simulation methods. Deterministic methods are based on the numerical solution of Boltzmann transport equation. Such are discrete ordinates (SN) and spherical harmonics (PN) methods. The stochastic simulation method for calculation of radiation transport is known as Monte Carlo method. In the deterministic methods the spatial geometry is partitioned into mesh elements. In SN method angular integrals of the transport equation are replaced with weighted sums over a set of discrete angular directions. Flux is calculated iteratively for all these mesh elements and for each discrete direction. Discrete ordinates transport codes used in the dosimetric calculations are ANISN, DORT and TORT. In PN method a Legendre expansion for angular flux is used instead of discrete direction fluxes, land the angular dependency comes a property of vector function space itself. Thus, only spatial iterations are required for resulting equations. A novel radiation transport code based on PN method and tree-multigrid technique (TMG) has been developed at VTT (Technical Research Centre of Finland). Monte Carlo method solves the radiation transport by randomly selecting neutrons and photons from a prespecified boundary source and following the histories of selected particles

  11. External Beam Radiation in Differentiated Thyroid Carcinoma

    Directory of Open Access Journals (Sweden)

    Salem Billan

    2016-01-01

    Full Text Available The treatment of differentiated thyroid carcinoma (DTC is surgery followed in some cases by adjuvant treatment, mostly with radioactive iodine (RAI. External beam radiotherapy (EBRT is less common and not a well-established treatment modality in DTC. The risk of recurrence depends on three major prognostic factors: extra-thyroid extension, patient’s age, and tumor with reduced iodine uptake. Increased risk for recurrence is a major factor in the decision whether to treat the patient with EBRT. Data about the use of EBRT in DTC are limited to small retrospective studies. Most series have demonstrated an increase in loco-regional control. The risk/benefit from giving EBRT requires careful patient selection. Different scoring systems have been proposed by different investigators and centers. The authors encourage clinicians treating DTC to become familiarized with those scoring systems and to use them in the management of different cases. The irradiated volume should include areas of risk for microscopic disease. Determining those areas in each case can be difficult and requires detailed knowledge of the surgery and pathological results, and also understanding of the disease-spreading pattern. Treatment with EBRT in DTC can be beneficial, and data support the use of EBRT in high-risk patients. Randomized controlled trials are needed for better confirmation of the role of EBRT.

  12. External exposure due to natural radiation (KINKI)

    International Nuclear Information System (INIS)

    1978-01-01

    A field survey of exposure rates due to natural radiation has been conducted throughout the Kinki district of Japan during both September and October 1973. In each location, measurements of exposures at one to fifteen sites, one of where contained 5 stations at least, were made. A total of 143 sites were measured. Observations were made using a spherical ionization chamber and several scintillation surveymeters. The spherical plastic ionization chamber of which inner diameter and wall thickness are 200 mm and 3 mm (acrylate) respectively has adequate sensitivity for field survey. The chamber was used as a standard of apparatus, but it is difficult to use the apparatus in all locations only by the apparatus, so that a surveymeter with a NaI(Tl) 1''phi x 1'' scintillator was used for regular measurements. Two types of surveymeters, the one with a 2''phi x 2'' NaI(Tl) scintillator and the other with a 3''phi x 3'' NaI(Tl) scintillator, were used as auxiliary devices. Both the chamber and the surveymeter were used in 20 sites and their readings were compared for drawing a relationship between them. Practically the direct reading of the surveymeter were reduced into the corresponding value of the plastic chamber through the relationship of linear proportion. Systematic error at calibration ( 60 Co) and reading error (rodoh) of the plastic chamber were within +-6% (maximum over all error) and within +-3.5% (standard error for 6μ R/hr) respectively. Reading error of the surveymeter is about +-3% (standard error for 6μ R/hr). Measurements in open bare field were made at one meter above the ground and outdoor gamma-rays exposure rates (μ R/hr) were due to cosmic rays as well as terrestrial radiation, as it may be considered that the contribution of fallout due to artificial origin was very small. (J.P.N.)

  13. Radiative forcing calculations for CH3Cl

    International Nuclear Information System (INIS)

    Grossman, A.S.; Grant, K.E.; Wuebbles, D.J.

    1994-06-01

    Methyl chloride, CH 3 Cl, is the major natural source of chlorine to the stratosphere. The production of CH 3 Cl is dominated by biological sources from the oceans and biomass burning. Production has a seasonal cycle which couples with the short lifetime of tropospheric CH 3 Cl to produce nonuniform global mixing. As an absorber of infrared radiation, CH 3 Cl is of interest for its potential affect on the tropospheric energy balance as well as for its chemical interactions. In this study, we estimate the radiative forcing and global warming potential (GWP) of CH 3 Cl. Our calculations use an infrared radiative transfer model based on the correlated k-distribution algorithm for band absorption. Global and annual average vertical profiles of temperature and trace gas concentration were assumed. The effects of clouds are modeled using three layers of global and annual average cloud optical properties. A radiative forcing value of 0.0053 W/m 2 ppbv was obtained for CH 3 Cl and is approximately linear in the background abundance. This value is about 2 percent of the forcing of CFC-11 and about 300 times the forcing of CO 2 , on a per molecule basis. The radiative forcing calculation for CH 3 Cl is used to estimate the global warming potential (GWP) of CH 3 Cl. The results give GWPs for CH 3 Cl of the order of 25 at a time of 20 years(CO 2 = 1). This result indicates that CH 3 Cl has the potential to be a major greenhouse gas if significant human related emissions were introduced into the atmosphere

  14. Calculating externalities from damages in occupational health and safety

    Energy Technology Data Exchange (ETDEWEB)

    Burtraw, D; Shefftz, J

    1994-07-01

    This paper surveys the theoretical basis for the possibility that coal miner occupational health and safety damages are not adequately internalized into the production cost of mining coal and thereby impose an external cost on society.

  15. Calculating externalities from damages in occupational health and safety

    International Nuclear Information System (INIS)

    Burtraw, D.; Shefftz, J.

    1994-01-01

    This paper surveys the theoretical basis for the possibility that coal miner occupational health and safety damages are not adequately internalized into the production cost of mining coal and thereby impose an external cost on society

  16. Measurement of man's exposure to external radiation

    International Nuclear Information System (INIS)

    Becker, K.

    1975-01-01

    After outlining briefly the rationale for personnel radiation monitoring with integrating detectors, a review is presented of some developments which have taken place in personnel and environmental dosimetry during the past 3.5 years. The results of a pilot field experiment concerning the stability of film and thermoluminescent dosimeters (TLDs) in four Latin-American countries are summarized. It shows that film dosimeters should be used only with caution, and in locations with a moderate climate. A survey is being conducted on the current status and trends in personnel monitoring, involving detailed questioning of over 150 laboratories in about forty countries to obtain information on the type of service and detectors, evaluation and recordkeeping, additional applications, problem and development areas, intercomparisons, practical experiences with different systems, administrative and legal aspects, etc. According to the preliminary results, the trend is away from photographic film and towards mostly automatic TLD systems, not only in the industrialized countries but also in several of the larger and more advanced developing countries. The need for higher quality standards and frequent performance tests under realistic conditions is emphasized. Differences in the requirements for personnel and []stationary environmental dosimeters are outlined. As evidenced by the results of a recent international intercomparison of such dosimeters under laboratory and field conditions, involving 56 dosimeter sets from eleven countries, reasonably accurate results can be obtained with several TLD systems including LiF, CaSO 4 :Dy, and CaF 2 :Mn; however CaF 2 :Dy is less reliable than the others and film is not adequate at all. Transit doses were found to be erratic and frequently high. Limitations in the assessment of population doses from stationary detector readings are discussed. (auth)

  17. Agriculture-related radiation dose calculations

    International Nuclear Information System (INIS)

    Furr, J.M.; Mayberry, J.J.; Waite, D.A.

    1987-10-01

    Estimates of radiation dose to the public must be made at each stage in the identification and qualification process leading to siting a high-level nuclear waste repository. Specifically considering the ingestion pathway, this paper examines questions of reliability and adequacy of dose calculations in relation to five stages of data availability (geologic province, region, area, location, and mass balance) and three methods of calculation (population, population/food production, and food production driven). Calculations were done using the model PABLM with data for the Permian and Palo Duro Basins and the Deaf Smith County area. Extra effort expended in gathering agricultural data at succeeding environmental characterization levels does not appear justified, since dose estimates do not differ greatly; that effort would be better spent determining usage of food types that contribute most to the total dose; and that consumption rate and the air dispersion factor are critical to assessment of radiation dose via the ingestion pathway. 17 refs., 9 figs., 32 tabs

  18. Monte Carlo calculations of channeling radiation

    International Nuclear Information System (INIS)

    Bloom, S.D.; Berman, B.L.; Hamilton, D.C.; Alguard, M.J.; Barrett, J.H.; Datz, S.; Pantell, R.H.; Swent, R.H.

    1981-01-01

    Results of classical Monte Carlo calculations are presented for the radiation produced by ultra-relativistic positrons incident in a direction parallel to the (110) plane of Si in the energy range 30 to 100 MeV. The results all show the characteristic CR(channeling radiation) peak in the energy range 20 keV to 100 keV. Plots of the centroid energies, widths, and total yields of the CR peaks as a function of energy show the power law dependences of γ 1 5 , γ 1 7 , and γ 2 5 respectively. Except for the centroid energies and power-law dependence is only approximate. Agreement with experimental data is good for the centroid energies and only rough for the widths. Adequate experimental data for verifying the yield dependence on γ does not yet exist

  19. Calculating the Responses of Self-Powered Radiation Detectors.

    Science.gov (United States)

    Thornton, D. A.

    Available from UMI in association with The British Library. The aim of this research is to review and develop the theoretical understanding of the responses of Self -Powered Radiation Detectors (SPDs) in Pressurized Water Reactors (PWRs). Two very different models are considered. A simple analytic model of the responses of SPDs to neutrons and gamma radiation is presented. It is a development of the work of several previous authors and has been incorporated into a computer program (called GENSPD), the predictions of which have been compared with experimental and theoretical results reported in the literature. Generally, the comparisons show reasonable consistency; where there is poor agreement explanations have been sought and presented. Two major limitations of analytic models have been identified; neglect of current generation in insulators and over-simplified electron transport treatments. Both of these are developed in the current work. A second model based on the Explicit Representation of Radiation Sources and Transport (ERRST) is presented and evaluated for several SPDs in a PWR at beginning of life. The model incorporates simulation of the production and subsequent transport of neutrons, gamma rays and electrons, both internal and external to the detector. Neutron fluxes and fuel power ratings have been evaluated with core physics calculations. Neutron interaction rates in assembly and detector materials have been evaluated in lattice calculations employing deterministic transport and diffusion methods. The transport of the reactor gamma radiation has been calculated with Monte Carlo, adjusted diffusion and point-kernel methods. The electron flux associated with the reactor gamma field as well as the internal charge deposition effects of the transport of photons and electrons have been calculated with coupled Monte Carlo calculations of photon and electron transport. The predicted response of a SPD is evaluated as the sum of contributions from individual

  20. Radiation damage calculations for the LANSCE degrader

    International Nuclear Information System (INIS)

    Ferguson, P.D.; Sommer, W.F.; Dudziak, D.J.; Wechsler, M.S.; Barnett, M.H.; Corzine, R.K.

    1998-01-01

    The A-6 water degrader at the Los Alamos Neutron Science Center (LANSCE) linear proton accelerator has an outer shell of Inconel 718. The degrader was irradiated by 800-MeV protons during 1988--1993 to an exposure of 5.3 ampere-hours (A h). As described in Ref. 1, material from the Inconel is currently being cut into specimens for microhardness, three-point bending, ball punch, microscopy, and corrosion tests. This paper is devoted to calculations of radiation damage, particularly displacement and He production, sustained by the degrader Inconel

  1. tion using external beam radiation in gynaecological cancers

    African Journals Online (AJOL)

    Enrique

    The purpose of the modified technique is: (i) to accurately assess the lower extent of the disease and define the lower border of the external radiation field in both the anteropos- terior/ posteroanterior (AP/PA) and lateral fields; and (ii) to decrease the field size and reduce treatment-related side-effects. Methods and materials.

  2. Dosimetry of external radiation: Recent developments. Advanced training course

    International Nuclear Information System (INIS)

    Ambrosi, P.; Boehm, J.; Doerschel, B.

    1999-02-01

    Between February 24 and 26, 1999, the Fachverband fuer Strahlenschutz e.V. held an advanced training course in Tabarz/Thuringia on the subject 'Dosimetry of external radiation: Recent developments'. The following subject matters were dealt with: New concepts and measurands; Present national and international rules; Measurement of the body dose; Exposure conditions at workplaces; and Present state of dosimetric metrology. In correspondence with the subject, the course was organized by the working group 'Dosimetry of external radiation'. Target groups of the course were persons bearing responsibility in the radiation protection sector and interested persons with basic knowledge of this field. The present report comprises the written versions of lectures delivered at the meeting. (orig.) [de

  3. Calculation of dose-rate conversion factors for external exposure to photons and electrons

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1978-01-01

    Methods are presented for the calculation of dose-rate conversion factors for external exposure to photon and electron radiation from radioactive decay. A dose-rate conversion factor is defined as the dose-equivalent rate per unit radionuclide concentration. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each radiation type and exposure mode, dose-rate conversion factors are derived for tissue-equivalent material at the body surface of an exposed individual. In addition, photon dose-rate conversion factors are estimated for 22 body organs. The calculations are based on the assumption that the exposure medium is infinite in extent and that the radionuclide concentration is uniform. The dose-rate conversion factors for immersion in contaminated air and water then follow from the requirement that all of the energy emitted in the radioactive decay is absorbed in the infinite medium. Dose-rate conversion factors for ground-surface exposure are calculated at a reference location above a smooth, infinite plane using the point-kernel integration method and known specific absorbed fractions for photons and electrons in air

  4. Explanation of nurse standard of external exposure acute radiation sickness

    International Nuclear Information System (INIS)

    Lu Xiuling; Jiang Enhai; Sun Feifei; Zhang Bin; Wang Xiaoguang; Wang Guilin

    2012-01-01

    National occupational health standard-Nurse Standard of External Exposure Acute Radiation Sickness has been approved and issued by the Ministry of Health. Based on the extensive research of literature, collection of the previous nuclear and radiation accidents excessive exposed personnel data and specific situations in China, this standard was enacted according to the current national laws, regulations, and the opinions of peer experts. It is mainly used for care of patients with acute radiation sickness, and also has directive significance for care of patients with iatrogenic acute radiation sickness which due to the hematopoietic stem cell transplantation pretreatment. To correctly carry out this standard and to reasonably implement nursing measures for patients with acute radiation sickness, the contents of this standard were interpreted in this article. (authors)

  5. Levels of external natural radiation and doses to population in Heilongjiang province

    International Nuclear Information System (INIS)

    Liang Yicheng; He Yongjiang; Wang Lu

    1985-01-01

    The external natural radiation level in Heilongjiang Province was measured by using China-made FD-71 scintillation radiometers and RSS-111 high pressure ionization chambers. The doses of external radiation to population were also calculated. The population-weighted average value of the absorbed dose rate from terrestrial γ-radiation was 7.2 x 10 -8 Gy.h -1 for outdoors, and 10.8 x 10 -8 Gy.h -1 for indoors. The population-weighted average absorbed dose rate in air from cosmic rays was 3.3 x 10 -8 Gy.h -1 . The annual population-weighted average effective dose equivalent and the annual collective effective dose equivalent from the environmental γ-radiation were 620 μSv and 20.1 x 10 3 man.Sv, respectively. The corresponding figures from cosmic rays were 260 μSv and 8.7 x 10 3 man.Sv, respectively

  6. Radiation shielding calculations for the vista spacecraft

    International Nuclear Information System (INIS)

    Sahin, Suemer; Sahin, Haci Mehmet; Acir, Adem

    2005-01-01

    The VISTA spacecraft design concept has been proposed for manned or heavy cargo deep space missions beyond earth orbit with inertial fusion energy propulsion. Rocket propulsion is provided by fusion power deposited in the inertial confined fuel pellet debris and with the help of a magnetic nozzle. The calculations for the radiation shielding have been revised under the fact that the highest jet efficiency of the vehicle could be attained only if the propelling plasma would have a narrow temperature distribution. The shield mass could be reduced from 600 tons in the original design to 62 tons. Natural and enriched lithium were the principle shielding materials. The allowable nuclear heating in the superconducting magnet coils (up to 5 mW/cm 3 ) is taken as the crucial criterion for dimensioning the radiation shielding structure of the spacecraft. The space craft mass is 6000 tons. Total peak nuclear power density in the coils is calculated as ∼5.0 mW/cm 3 for a fusion power output of 17 500 MW. The peak neutron heating density is ∼2.0 mW/cm 3 , and the peak γ-ray heating density is ∼3.0 mW/cm 3 (on different points) using natural lithium in the shielding. However, the volume averaged heat generation in the coils is much lower, namely 0.21, 0.71 and 0.92 mW/cm 3 for the neutron, γ-ray and total nuclear heating, respectively. The coil heating will be slightly lower if highly enriched 6 Li (90%) is used instead of natural lithium. Peak values are then calculated as 2.05, 2.15 and 4.2 mW/cm 3 for the neutron, γ-ray and total nuclear heating, respectively. The corresponding volume averaged heat generation in the coils became 0.19, 0.58 and 0.77 mW/cm 3

  7. Radiation-induced external ear canal cholesteatoma-like disease

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, Akiko; Okuno, Hideji; Noguchi, Keisuke; Komatsuzaki, Atsushi [Tokyo Medical and Dental Univ. (Japan). School of Medicine

    1999-06-01

    Three cases of cholesteatoma-like disease in the ear canals after radiation therapy for head and neck tumor were reported. Effect of irradiation on bone and soft tissue including skin brings about pathological reaction to the external ear canal as well. Two types of disease resembling cholesteatomas have been recognized: keratosis obturans (KO) and external auditory canal cholesteatoma (EACC). KO appears to be derived from disease of canal skin involved with keratinization, creating a widning of the canal. EACC, on the other hand, seems to develop in the disease of bony canal where a localized absorption of its bone with invasion of squamous epithelium takes place. (author)

  8. Radiative forcing calculations for CH3Br

    International Nuclear Information System (INIS)

    Grossman, A.S.; Blass, W.E.; Wuebbles, D.J.

    1995-06-01

    Methyl Bromide, CH 3 Br, is the major organobromine species in the lower atmosphere and is a primary source of bromine in the stratosphere. It has a lifetime of 1.3 years. The IR methyl bromide spectra in the atmospheric window region, 7--13μ, was determined using a well tested Coriolis resonance and ell-doubling (and ell-resonance) computational system. A radiative forcing value of 0.00493 W/m 2 /ppbv was obtained for CH 3 Br and is approximately linear in the background abundance. This value is about 2 percent of the forcing of CFC-11 and about 278 times the forcing of C0 2 , on a per molecule basis. The radiative forcing calculation is used to estimate the global warming potential (GWP) of CH 3 Br. The results give GWPs for CH 3 Br of the order of 13 for an integration period of 20 years and 4 for an integration period of 100 years (assuming C0 2 = 1, following IPCC [1994]). While CH 3 Br has a GWP which is approximately 25 percent of the GWP of CH 4 , the current emission rates are too low to cause serious atmospheric greenhouse heating effects at this time

  9. Natural external radiation level and population dose in Hunan province

    International Nuclear Information System (INIS)

    1985-01-01

    A survey of the natural external radiation level in Hunan Province is reported. The measurements were performed with FD-71 scintillation radiometers. On the basis of measurements at about 1,600 locations, the contribution from cosmic radiation is found to be 3.0 x 10 -8 Gy.h -1 , and the average absorbed dose rates in air from terrestrial γ-radiation for outdoors, indoors and roads are determined to be 9.2, 13.1 and 9.0 x 10 -8 Gy.h -1 , respectively. The γ-radiation indoors is markedly higher than that outdoors by a factor of 1.42. The lowest γ-radiation level is found in the sedimentary plain around Donting Lake, while the highest absorbed dose rates in air from terrestrial radiation are observed in some areas with exposed granites. The indoor γ-radiation in brick houses is markedly higher than that in wooden houses. Tarred roads have evidently lower radiation level than sand-gravel roads or concrete roads. The annual effective dose equivalents to the population from cosmic and terrestrial sources are 0.256 and 0.756 mSv, respectively, with a total value of 1.012 mSv

  10. Dosimetry services for internal and external radiation sources

    International Nuclear Information System (INIS)

    1988-01-01

    The Canadian Atomic Energy Control Board (AECB) sets radiation dose limits for the operation of nuclear facilities and the possession of prescribed substances within Canada. To administer these regulations the AECB must be satisfied that the dosimetry services used by a licensee meet adequate standards. Licensees are required to use the Occupational Dosimetry Service operated by the Bureau of Radiation and Medical Devices, Department of National Health and Welfare (BRMD) to determine doses from external sources of radiation, except where a detailed rationale is given for using another service. No national dosimetry service exists for internal sources of radiation. Licensees who operate or use a dosimetry service other than the BRMD must provide the AECB with evidence of the competence of the staff and adequacy of the equipment, techniques and procedures; provide the AECB with evidence that a quality assurance program has been implemented; and send individual dose or exposure data to the National Dose Registry. (L.L.)

  11. Data for absorbed dose calculations for external sources and for emitters within the body

    International Nuclear Information System (INIS)

    Hep, J.; Valenta, V.

    1976-01-01

    Tables give data for the calculation of absorbed doses from radioactivity sources accumulated in individual body organs. The tables are arranged in such manner that the gamma energy (J) absorbed in 1 kg of target organ (19 organs and total body) are given for 18 source organs (16 different organs, total doby and surrounding air) resulting from 1 decay event, this for more than 250 radioisotopes evenly distributed in the source organ (1 J/kg=100 rad). Also given are the energies of alpha and beta radiations related to one decay. In tables having the surrounding air as the source it is assumed that the intensity of the external source is 1 decay per 1 m 3 of surrounding air which is constant in the entire half-space. The tables are only elaborated for radioisotopes with a half-life of more than 1 min. (B.S.)

  12. External radiation exposure control system in accelerator facilities

    International Nuclear Information System (INIS)

    Ogawa, Tatsuhiko; Iimoto, Takeshi; Kosako, Toshiso

    2011-01-01

    The external exposure control systems in KEK and CERN are discussed to find out good practices and unreasonableness of radiation control in accelerator facilities, which plays an important role in optimizing national and/or site specific radiological regulations, referring to relevant ICRP publications. Personal dose limits and radiation area classifications were analyzed and their reasonableness were explored. Good example of supervised areas, area classification based on realistic assumptions on working time etc are found. On the other hand, unreasonable systems, that are often attributed to the national regulation or ideas presented in the old publications are also found. (author)

  13. Influence of external action and structural factors on radiation blistering

    International Nuclear Information System (INIS)

    Kalin, B.A.; Chernov, I.I.; Fomina, E.P.; Korshunov, S.H.; Polsky, V.I.; Skorov, D.M.; Yakushin, V.L.

    1985-01-01

    A survey of experimental results is presented, pertaining to radiation blistering of a considerable number of materials (stainless steels, alloys with high nickel content, alloys of refractory metals) under helium ion irradiation with energies of 20-100 keV under conditions corresponding to the plasma-wall interaction: bombardment at various angles of incidence and cyclic irradiation in a wide spectrum of ion incidence angles; influence of external action, including thermocyclic; influence of preceding neutron and proton irradiation. It has been shown that external factors have a complex influence on blister parameters and erosion coefficients of materials. A study has been carried out on the influence of aluminium coatings, alloying additions, phase state of material and microstructure on the nature and degree of surface erosion. Complex influence of element and phase composition, as well as microstructural changes during heat treatment and welding on radiation erosion have been established. (orig.)

  14. PABLM: a computer program to calculate accumulated radiation doses from radionuclides in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.; Kennedy, W.E. Jr.; Soldat, J.K.

    1980-03-01

    A computer program, PABLM, was written to facilitate the calculation of internal radiation doses to man from radionuclides in food products and external radiation doses from radionuclides in the environment. This report contains details of mathematical models used and calculational procedures required to run the computer program. Radiation doses from radionuclides in the environment may be calculated from deposition on the soil or plants during an atmospheric or liquid release, or from exposure to residual radionuclides in the environment after the releases have ended. Radioactive decay is considered during the release of radionuclides, after they are deposited on the plants or ground, and during holdup of food after harvest. The radiation dose models consider several exposure pathways. Doses may be calculated for either a maximum-exposed individual or for a population group. The doses calculated are accumulated doses from continuous chronic exposure. A first-year committed dose is calculated as well as an integrated dose for a selected number of years. The equations for calculating internal radiation doses are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and MPC's of each radionuclide. The radiation doses from external exposure to contaminated water and soil are calculated using the basic assumption that the contaminated medium is large enough to be considered an infinite volume or plane relative to the range of the emitted radiations. The equations for calculations of the radiation dose from external exposure to shoreline sediments include a correction for the finite width of the contaminated beach.

  15. Neutronic calculations for a subcritical system with external source

    International Nuclear Information System (INIS)

    Cintas, A; Lopasso, E.M; Marquez Damian, J. I

    2006-01-01

    We present a neutronic study on an A D S, systems capable of transmute minor actinides and fission products in order to reduce their radiotoxicity and mean-life.We compare neutronic parameters obtained with Scale/Tort and M C N P modelling a sub-critical system with source from a N E A Benchmark.Due to lack of nuclear data at the temperature of the system, we perform calculations at available temperature of libraries (300 K); to compensate the reactivity insertion due to the temperature change we reduce the size of the fuel zone in order to get a sub-critical system that allow u s to evaluate neutronic parameters of the system with source.We have found that the numerical results (neutron spectrum, neutron flux distributions and other neutronic parameters) are in agreement with the M C N P and with those of the benchmark participants even though the geometric models used are not exactly the same. We conclude that with the real temperature cross sections, the calculation scheme developed (Scale/Tort and M C N P) will give reliable results in A D S evaluations [es

  16. Review of retrospective dosimetry techniques for external ionising radiation exposures

    International Nuclear Information System (INIS)

    Ainsbury, E. A.; Bakhanova, E.; Barquinero, J. F.; Brai, M.; Chumak, V.; Correcher, V.; Darroudi, F.; Fattibene, P.; Gruel, G.; Guclu, I.; Horn, S.; Jaworska, A.; Kulka, U.; Lindholm, C.; Lloyd, D.; Longo, A.; Marrale, M.; Monteiro Gil, O.; Oestreicher, U.; Pajic, J.; Rakic, B.; Romm, H.; Trompier, F.; Veronese, I.; Voisin, P.; Vral, A.; Whitehouse, C. A.; Wieser, A.; Woda, C.; Wojcik, A.; Rothkamm, K.

    2011-01-01

    The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements. (authors)

  17. Normal tissue tolerance to external beam radiation therapy: Esophagus

    International Nuclear Information System (INIS)

    Bera, G.; Pointreau, Y.; Denis, F.; Dupuis, O.; Orain, I.; Crehange, G.

    2010-01-01

    The esophagus is a musculo-membranous tube through which food passes from the pharynx to the stomach. Due to its anatomical location, it can be exposed to ionizing radiation in many external radiotherapy indications. Radiation-induced esophageal mucositis is clinically revealed by dysphagia and odynophagia, and usually begins 3 to 4 weeks after the start of radiation treatment. With the rise of multimodality treatments (e.g., concurrent chemoradiotherapy, dose escalation and accelerated fractionation schemes), esophageal toxicity has become a significant dose-limiting issue. Understanding the predictive factors of esophageal injury may improve the optimal delivery of treatment plans. It may help to minimize the risks, hence increasing the therapeutic ratio. Based on a large literature review, our study describes both early and late radiation-induced esophageal injuries and highlights some of the predictive factors for cervical and thoracic esophagus toxicity. These clinical and dosimetric parameters are numerous but none is consensual. The large number of dosimetric parameters strengthens the need of an overall analysis of the dose/volume histograms. The data provided is insufficient to recommend their routine use to prevent radiation-induced esophagitis. Defining guidelines for the tolerance of the esophagus to ionizing radiation remains essential for a safe and efficient treatment. (authors)

  18. Adenocarcinoma of the rectum treated by radical external radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Catton, Charles N; Brierley, James D; Cummings, Bernard J; Wong, C Shun; Keane, Thomas J; O' Sullivan, Brian; Goodman, Phyllis

    1995-01-15

    Purpose: To assess the long-term survival and response rates of patients with primary rectal cancer to radical radiation therapy. Methods and Materials: Between 1978 and 1987, 229 patients were treated at the Princess Margaret Hospital with radical external radiation therapy for adenocarcinoma of the rectum. Patients were treated with radiation either because they were considered to have unresectable tumors, were medically unfit, or refused surgery, or for a combination of these factors. Doses ranged from 40 Gy in 10 fractions by a split course over 6 weeks to 60 Gy in 30 fractions in 6 weeks. The most commonly prescribed treatment was 52 Gy target absorbed dose in 20 daily fractions over 4 weeks. Results: The overall 5-year actuarial survival rate was 27%; for patients with mobile tumors, it was 48%, partially fixed 27%, and fixed tumor 4%. Forty-eight of the 97 patients (50%) with mobile tumors, 11 of the 37 patients (30%) with partially fixed tumors, and 7 of the 77 patients (9%) with fixed tumors had clinically complete tumor regression following radiation. Of these, 18 of the mobile, 6 of the partially fixed, and 5 of the fixed tumors later relapsed locally. Fifty patients had salvage surgery after failing to achieve complete remission or for local relapse, with a 5-year actuarial survival rate of 42% from the time of surgery. Conclusion: Although radiation therapy can cure some patients with mobile or partially fixed rectal adenocarcinomas who refuse or are unsuitable for surgery, local control remains a problem; salvage surgery should be considered in patients who relapse or fail to go into complete remission and who are fit to undergo surgery. For patients with fixed rectal cancers, high-dose external-beam radiation should be part of a planned preoperative regimen or be palliative in intent.

  19. Calculation of external buildings of 1300 MW PWR

    International Nuclear Information System (INIS)

    Chataignier, Jacques

    1981-01-01

    The outer containment of reactor building is composed of a cylindrical reinforced unprestressed concrete shell. Two kinds of stress have been taken into account for dimensioning the steels and checking the concrete stresses; these are: - cases of so called ''normal'' stresses that the structure is supposed to withstand without there being any effect on its operational conditions and durability, - cases of so called ''increased'' stresses which if exceeded correspond to the ruin of the structure. The strains created in the structure by the different sorts of stresses were determined by computer with the help of calculation models by finite element method to which loads are applied, broken down, as the case may be, into Fourier series when they are not axisymmetrical [fr

  20. Radiation optic neuropathy after external beam radiation therapy for acromegaly: report of two cases

    International Nuclear Information System (INIS)

    Bergh, Alfons C.M. van den; Hoving, Marjanke A.; Links, Thera P.; Dullaart, Robin P.F.; Ranchor, Adelita V.; Weeme, Cees A. ter; Canrinus, Alof A.; Szabo, Ben G.; Pott, Jan-Willem R.

    2003-01-01

    For diagnosing radiation optic neuropathy (RON) ophthalmological and imaging data were evaluated from 63 acromegalic patients, irradiated between 1967 and 1998. Two patients developed RON: one patient in one optic nerve 10 years and another patient in both optic nerves 5 months after radiation therapy. RON is a rare complication after external beam radiation therapy for acromegaly, which can occur after a considerable latency period

  1. Years of life lost due to external radiation exposure

    International Nuclear Information System (INIS)

    Raicevic, J.J.; Merkle, J.M.; Ehrhardt, J.; Ninkovic, M.M.

    2002-01-01

    A new approach for calculation of the years of life lost per excess death (YLL) due to stochastic health effects is applied to external exposure pathways. The short-term external exposures are due to the passage of radioactive cloud (CL) and due to the skin and clothes contamination (SK). The long-term external exposure is the one from the radioactive material deposited on ground (GR). Three nuclides, 131 I , 137 Cs and 239 Pu with extremely wide range of the half-life are considered to examine its possible influence on the calculated YLL values. For each of these nuclides, the YLL is found as a decreasing function of the age at exposure and presented graphically in this paper. Another negative correlation is established between the fully averaged YLL and the duration of the nuclide's half-life has been found for protracted exposure (GR). On the other hand, the YLL for the short-term external exposures (CL and SK) practically does not depend on the nuclide's half-life. In addition, a weak YLL dependence of the dose was commented. (author)

  2. Years of life lost due to external radiation exposure

    Directory of Open Access Journals (Sweden)

    Raičević Jagoš J.

    2004-01-01

    Full Text Available In this paper a new approach for calculation of the years of life lost per excess death due to stochastic health effects is applied to external exposure pathways. The short-term external exposures are due to the passage of radioactive cloud and due to the skin and clothes contamination. The long-term external exposure is the one from the radioactive material deposited on the ground (groundshine. Three nuclides, 131I, 137Cs, and 239Pu, and with the extremely wide range of half-life are considered in order to examine their possible influence on the calculated values of years of life lost. For each of these nuclides, the number of years of life lost has been found as a decreasing function of the age at the expo sure and presented graphically in this paper. For protracted exposures, the fully averaged number of years of life lost is negative correlated with the nuclide’s half-life. On the other hand, the short-term external exposures do not depend on the nuclide’s half-life. In addition, a weak years of life lost dependence of the dose has been commented.

  3. New model for mines and transportation tunnels external dose calculation using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Allam, Kh. A.

    2017-01-01

    In this work, a new methodology is developed based on Monte Carlo simulation for tunnels and mines external dose calculation. Tunnels external dose evaluation model of a cylindrical shape of finite thickness with an entrance and with or without exit. A photon transportation model was applied for exposure dose calculations. A new software based on Monte Carlo solution was designed and programmed using Delphi programming language. The variation of external dose due to radioactive nuclei in a mine tunnel and the corresponding experimental data lies in the range 7.3 19.9%. The variation of specific external dose rate with position in, tunnel building material density and composition were studied. The given new model has more flexible for real external dose in any cylindrical tunnel structure calculations. (authors)

  4. 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.)

  5. Studies of workers exposed to low doses of external radiation

    International Nuclear Information System (INIS)

    Gilbert, E.S.

    1991-04-01

    Currently, several epidemiologic studies of workers who have been exposed occupationally to low levels of radiation are being conducted, and include studies of workers in the United States, Great Britain, and Canada involved in the production of both defense materials and nuclear power. This paper focuses on studies that evaluate the possible adverse effects resulting from external exposure to radiation. The radiation risk estimates that have been used to establish radiation protection standards for workers and others have been obtained mainly from studies of persons exposed at high doses and dose rates. However, questions remain with regard to the extrapolation process that has been necessary for estimating low-level radiation risks. Occupational studies provide a direct assessment of risk based on data on persons exposed at the actual levels of interest. If current risk estimates are correct, these studies have very little chance of detecting risk, but can still be used to provide useful upper limits on risks. The studies are also adequate to detect serious underestimation of risks. 36 refs., 3 figs., 3 tabs

  6. Fertility of women after exposure to internal and external radiation

    International Nuclear Information System (INIS)

    Polednak, A.P.

    1982-01-01

    Fertility was examined in 199 women exposed to internal and external radiation while employed in the radium watch-dial painting industry in Illinois between 1916 and 1929. In women with at least one live birth, mean log live-birth rate was significantly lower in the highest (estimated) ovarian-dose group (i.e., greater than or equal to 20 rem) than in the lowest group (<5 rem). In multiple regression analysis, intake dose (proportional to alpha-particle dose to ovaries) but not duration of employment (relevant to external gamma-ray dose to ovaries) was a statistically significant predictor of log live-birth rate. There was no evidence for an increase in fetal deaths with increasing ovarian dose level (rem). This suggests that the findings on live-birth rate may not involve post-implantation dominant lethal mutations, but pre-implantation losses could not be evaluated. Some possible explanations for these findings are discussed

  7. Fertility of women after exposure to internal and external radiation

    International Nuclear Information System (INIS)

    Polednak, A.P.

    1980-01-01

    Fertility was examined in 199 women exposed to internal and external radiation while employed in the radium watch-dial painting industry in Illinois between 1916 and 1929. In women with at least one live birth, mean log live-birth rate was significantly lower in the highest (estimated) ovarian-dose group (i.e., greater than or equal to 20 rem) than in th lowest group (<5 rem). In multiple regression analysis, intake dose (proportional to alpha-particle dose to ovaries) but not duration of employment (relevant to external gamma-ray dose to ovaries) was a statistically significant predictor of log live-birth rate. There was no evidence for an increase in fetal deaths with increasing ovarian dose level (rem). This suggests that the findings on live-birth rate may not involve post-implantation dominant lethal mutations, but preimplantation losses could not be evaluated. Some possible explanations for these findings are discussed

  8. Dose evaluation for external exposure in radiation accidents

    International Nuclear Information System (INIS)

    Maruyama, Takashi

    1989-01-01

    Abnormal exposures including emergency and accidental are categorized into external exposure and internal contamination, although both of these may be associated with external contamination. From a point of view of lifesaving in the abnormal exposures, it is primarily important to evaluate radiation dose of exposed persons as soon as possible. This report reviews the status of early dosimetry in the accidental exposures and discusses the optimum methodology of the early dose determination for external exposures in abnormal exposures. Personal monitors generally give an indication of dose to an exposed person only at a single part of the body. The data obtained from the personal monitors should be interpreted with care and in the light of information about the circumstances of exposure. In most cases, the records of environmental monitors or the survey with area monitors provide valuable information on the radiation fields. In the some cases, the reconstruction of the abnormal exposure is required for the dose evaluation by means of phantom experiments. In the case of neutron exposures, activation products in the body or its components or personnel possession can be useful for the early dosimetry. If the dose received by the whole body is evaluated as being very high, clinical observations and biological investigations may be more important guide to initial medical treatment than the early dosimetry. For the dose evaluation of general public, depending on the size of abnormal exposure, information that could be valuable in the assessment of abnormal exposures will come from the early dose estimates with environmental monitors and radiation survey meters. (author)

  9. Use of calculations in the hygienic evaluation and prediction of external γ-irradiation levels of population

    International Nuclear Information System (INIS)

    Karpov, V.I.

    1980-01-01

    The estimation method of the annual average equivalent dose of population external irradiation calculated per 1 person and collective dose using the data of gamma radiation in buildings and inhabited points is proposed. The modified ratio (from the report of UN Scientific Committee, 1977) for the determination of external irradiation dose per 1 person is given. Dynamics and value of population exposure are determined. Particular solutions with a number of corresponding approximating functions are proposed for concrete rural and urban conditions. It is shown that with the construction of stone buildings collective dose growth considerably passes ahead of the population growth. Dynamics of the population radiation dose is forecasted upto 2000 year. It is shown that the cumulative error does not exceed +-25%

  10. An intercomparison of Canadian external dosimetry processors for radiation protection

    International Nuclear Information System (INIS)

    1989-10-01

    The five Canadian external dosimetry processors have participated in a two-stage intercomparison. The first stage involved dosimeters to known radiation fields under controlled laboratory conditions. The second stage involved exposing dosimeters to radiation fields in power reactor working environments. The results for each stage indicated the dose reported by each processor relative to an independently determined dose and relative to the others. The results of the intercomparisons confirm the original supposition: namely that the average differences in reported dose among five processors are much less than the uncertainty limits recommended by the ICRP. This report provides a description of the experimental methods as well as a discussion of the results for each stage. The report also includes a set of recommendations

  11. External radiotherapy. Particle accelerator - Radiation protection: medical sheet ED 4246

    International Nuclear Information System (INIS)

    2007-06-01

    After having indicated the required authorizations for the use of external radiotherapy installations, this document presents the various aspects and measures related to radiation protection of workers when performing such treatments. It presents the concerned personnel, describes the operational process, indicates the associated hazards and the risk related to ionizing radiation, and describes how the risk is to be assessed and how exposure levels are to be determined (elements of risk assessment, delimitation of controlled and monitored areas, personnel classification, and choice of the dose monitoring method). It describes the various components of a risk management strategy (risk reduction, technical measures regarding the installation and the personnel, training and information, prevention and medical monitoring). It briefly presents how risk management is to be assessed, and mentions other related risks

  12. Calculation codes in radiation protection, radiation physics and dosimetry; Codes de calcul en radioprotection, radiophysique et dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    These scientific days had for objective to draw up the situation of calculation codes of radiation transport, of sources estimation, of radiation doses managements and to draw the future perspectives. (N.C.)

  13. Radiation damage calculations for compound materials

    International Nuclear Information System (INIS)

    Greenwood, L.R.

    1990-01-01

    This paper reports on the SPECOMP computer code, developed to calculate neutron-induced displacement damage cross sections for compound materials such as alloys, insulators, and ceramic tritium breeders for fusion reactors. These new calculations rely on recoil atom energy distributions previously computed with the DISCS computer code, the results of which are stored in SPECTER computer code master libraries. All reaction channels were considered in the DISCS calculations and the neutron cross sections were taken from ENDF/B-V. Compound damage calculations with SPECOMP thus do not need to perform any recoil atom calculations and consequently need no access to ENDF or other neutron data bases. The calculations proceed by determining secondary displacements for each combination of recoil atom and matrix atom using the Lindhard partition of the recoil energy to establish the damage energy

  14. Internal and external radiation exposures of Fukushima residents

    International Nuclear Information System (INIS)

    Hayano, Ryugo

    2014-01-01

    The soil at Fukushima prefecture and its outskirts was heavily contaminated with radioactive materials from the troubled Fukushima Daiichi nuclear power plant, and the residents suffered risk from internal and external radiation exposure. At first, the average dose of internal radiation exposure was estimated to be several mSv based upon the results of Chernobyl nuclear disaster. But the result of massive measurements using whole body counters shows that the average quantity of internal radioactive cesium is less than that at the Cold Water period. In the meantime, someone shows exposure dose much higher than the average. The distribution of these abnormal doses is called 'Long Tail'. One must pay attention to the long tail at the assessment of the internal radiation exposure by Fukushima nuclear disaster. The main origin of the long tail is related to frequency eating of special food. It is thus important to find persons situated in the long tail and give them guidance on the meals. (J.P.N.)

  15. Kinetic neoclassical calculations of impurity radiation profiles

    Directory of Open Access Journals (Sweden)

    D.P. Stotler

    2017-08-01

    Full Text Available Modifications of the drift-kinetic transport code XGC0 to include the transport, ionization, and recombination of individual charge states, as well as the associated radiation, are described. The code is first applied to a simulation of an NSTX H-mode discharge with carbon impurity to demonstrate the approach to coronal equilibrium. The effects of neoclassical phenomena on the radiated power profile are examined sequentially through the activation of individual physics modules in the code. Orbit squeezing and the neoclassical inward pinch result in increased radiation for temperatures above a few hundred eV and changes to the ratios of charge state emissions at a given electron temperature. Analogous simulations with a neon impurity yield qualitatively similar results.

  16. Radiative flux calculations at UV and visible wavelengths

    International Nuclear Information System (INIS)

    Grossman, A.S.; Grant, K.E.; Wuebbles, D.J.

    1993-10-01

    A radiative transfer model to calculate the short wavelength fluxes at altitudes between 0 and 80 km has been developed at LLNL. The wavelength range extends from 175--735 nm. This spectral range covers the UV-B wavelength region, 250--350 nm, with sufficient resolution to allow comparison of UV-B measurements with theoretical predictions. Validation studies for the model have been made for both UV-B ground radiation calculations and tropospheric solar radiative forcing calculations for various ozone distributions. These studies indicate that the model produces results which agree well with respect to existing UV calculations from other published models

  17. LDRD Final Review: Radiation Transport Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Goorley, John Timothy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Morgan, George Lake [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lestone, John Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-06-22

    Both high-fidelity & toy simulations are being used to understand measured signals and improve the Area 11 NDSE diagnostic. We continue to gain more and more confidence in the ability for MCNP to simulate neutron and photon transport from source to radiation detector.

  18. External radiotherapy in macular degeneration: Our technique, dosimetric calculation, and preliminary results

    International Nuclear Information System (INIS)

    Akmansu, M.; Dirican, Bahar; Oeztuerk, Berrin; Egehan, Ibrahim; Subasi, Mahmut; Or, Meral

    1998-01-01

    Purpose: This study was performed to determine the toxicity and efficacy of external-beam radiotherapy in patients with age-related subfoveal neovascularization. Methods and Materials: Between January 1996 and September 1996, 25 patients with a mean age of 70.5 (60-84) years were enrolled. All patients underwent fluorescein angiographic evaluation and documentation of their neovascular disease prior to irradiation. A total of 25 patients were treated with a total dose of 12 Gy in 6 fractions over 8 days. We used a lens-sparing technique and patients were treated with a single lateral 6-MV photon beam. To assess the risk of radiation carcinogenesis after treatment of age-related subfoveal neovascularization, we estimated the effective dose for a standard patient on the basis of tissue-weighting factors as defined by the International Commission on Radiological Protection (ICRP). The calculations were made with TLD on a male randophantom. The lens dose was found to be 0.217 Gy per fraction. Results: No significant acute morbidity was noted. Visual acuity was maintained or improved in 76% and 80% of treated patients at their 1- and 3-month follow-up examinations, respectively. On angiographic imaging, there was stabilization of subfoveal neovascular membranes in 23 patients (92%) at 3 months after irradiation. Conclusion: Our observations on these 25 patients in this study indicate that many patients will have improved or stable vision after radiotherapy treatment with low-dose irradiation

  19. Radiation damage calculations for compound materials

    International Nuclear Information System (INIS)

    Greenwood, L.R.

    1989-01-01

    Displacement damage calculations can be performed for 40 elements in the energy range up to 20 MeV with the SPECTER computer code. A recent addition to the code, called SPECOMP, can intermix atomic recoil energy distributions for any four elements to calculate the proper displacement damage for compound materials. The calculations take advantage of the atomic recoil data in the SPECTER libraries, which were determined by the DISCS computer code, using evaluated neutron cross section and angular distribution data in ENDF/B-V. Resultant damage cross sections for any compound can be added to the SPECTER libraries for the routine calculation of displacements in any given neutron field. Users do not require access to neutron cross section files. Results are presented for a variety of fusion materials and a new ceramic superconductor material. Future plans and nuclear data needs are discussed. 11 refs., 6 figs., 1 tab

  20. Fertility of women after exposure to internal and external radiation

    International Nuclear Information System (INIS)

    Polednak, A.P.

    1980-01-01

    Fertility was examined in 199 women exposed to internal and external radiation while employed in the radium watch-dial painting industry in Illinois between 1916 and 1929. In women with at least one live birth, mean log live-birth rate was significantly lower in the highest (estimated) ovarian-dose group than in the lowest group. In multiple regression analysis, intake dose but not duration of employment was a statistically significant predictor of log live-birth rate. There was no evidence for an increase in fetal deaths with increasing ovarian dose level (rem). This suggests that the findings on live-birth rate may not involve post-implantation dominant lethal mutations, but preimplantation losses could not be evaluated. Some possible explanations for these findings are discussed

  1. Modeling of external radiation from the transport of radionuclides across a canyon

    International Nuclear Information System (INIS)

    Bowen, B.M.; Olsen, W.A.; Van Etten, D.; Chen, I-li.

    1986-01-01

    The Los Alamos Meson Physics Facility (LAMPF) is an 800-million electron volt, l mA intensity linear proton accelerator used for studying subatomic particles at relativistic velocities. Routine operation of the accelerator results in the formation of short-lived air activation products, primarily in the beam stop section of LAMPF. This study presents the results of monitoring and modeling external radiation levels from LAMPF emissions at three locations during 1984. Measured radiation exposures are presented for all three locations during a 49-day period. Hourly radiation levels are calculated for all sites and compared with the prevalent wind patterns during the study period. Predicted daily levels are compared with measured values at all of the sites. Accuracy of the model is compared for day and night conditions. Annual model predictions are also compared with TLD measurements

  2. Time delays between core power production and external detector response from Monte Carlo calculations

    International Nuclear Information System (INIS)

    Valentine, T.E.; Mihalczo, J.T.

    1996-01-01

    One primary concern for design of safety systems for reactors is the time response of external detectors to changes in the core. This paper describes a way to estimate the time delay between the core power production and the external detector response using Monte Carlo calculations and suggests a technique to measure the time delay. The Monte Carlo code KENO-NR was used to determine the time delay between the core power production and the external detector response for a conceptual design of the Advanced Neutron Source (ANS) reactor. The Monte Carlo estimated time delay was determined to be about 10 ms for this conceptual design of the ANS reactor

  3. Generating AN Optimum Treatment Plan for External Beam Radiation Therapy.

    Science.gov (United States)

    Kabus, Irwin

    1990-01-01

    The application of linear programming to the generation of an optimum external beam radiation treatment plan is investigated. MPSX, an IBM linear programming software package was used. All data originated from the CAT scan of an actual patient who was treated for a pancreatic malignant tumor before this study began. An examination of several alternatives for representing the cross section of the patient showed that it was sufficient to use a set of strategically placed points in the vital organs and tumor and a grid of points spaced about one half inch apart for the healthy tissue. Optimum treatment plans were generated from objective functions representing various treatment philosophies. The optimum plans were based on allowing for 216 external radiation beams which accounted for wedges of any size. A beam reduction scheme then reduced the number of beams in the optimum plan to a number of beams small enough for implementation. Regardless of the objective function, the linear programming treatment plan preserved about 95% of the patient's right kidney vs. 59% for the plan the hospital actually administered to the patient. The clinician, on the case, found most of the linear programming treatment plans to be superior to the hospital plan. An investigation was made, using parametric linear programming, concerning any possible benefits derived from generating treatment plans based on objective functions made up of convex combinations of two objective functions, however, this proved to have only limited value. This study also found, through dual variable analysis, that there was no benefit gained from relaxing some of the constraints on the healthy regions of the anatomy. This conclusion was supported by the clinician. Finally several schemes were found that, under certain conditions, can further reduce the number of beams in the final linear programming treatment plan.

  4. External radiation levels in installations of nuclear technology center

    International Nuclear Information System (INIS)

    Maletta, Paulo Guilherme M.; Filipetto, Joao; Wakabayashi, Tetsuaki; Silva, Teogenes A. da

    2005-01-01

    The radiological protection is a basic activity of nuclear technology center so that can carry through its activities with security, having to be planned and executed with total effectiveness. One of the basic tools of the radiological protection is the adoption of monitoring programs, that have as objective generality to evaluate the radiological conditions of the workstation and to assure that these conditions are acceptable safe for the displayed individuals, either workers or members of the public, as established in the basic norms of radiological protection. The Centro de Desenvolvimento da Tecnologia Nuclear - CDTN, first institution in Brazil, created in 1952 to entirely dedicate the related works to the nuclear area, to own 39 building, of which they are kept the Triga Reactor, Irradiation Gamma Laboratory, Reject Laboratory, Calibration Dosemeters Laboratory and others. In such installations, radioactive materials are produced, handled, processed and stored, being necessary the levels of external radiation ambient monitoring. As part of the radioprotection plan, monitoring 63 points on strategically located in the external areas to the building of CDTN, using characterized and calibrated thermoluminescence dosemeters. This work describes the dose distribution of the points, the doses evaluation procedure and the 4 results carried through between 2001 and 2004. The data demonstrate the attendance to the level of security established in the basic norm, what it contributed for the operation licensing of to the IBAMA. (author)

  5. External radiation therapy in early stage prostate cancer

    International Nuclear Information System (INIS)

    Sandler, Howard M.

    1996-01-01

    Optimal therapy for adenocarcinoma of the prostate is controversial. Numerous options are available, however, comparison of results is difficult in view of the insufficiency of phase III randomized trials comparing alternative treatment strategies. These options include such strategies as no curative therapy (so-called watchful waiting), radiotherapy (external and/or internal), cryotherapy, or radical prostatectomy. Clearly, a broad spectrum of clinical approaches. When reported experiences involving radiation therapy and radical prostatectomy are compared, surgical patients tend to be younger, of earlier stage, of higher performance status, and have lower pre-therapy PSA. These prognostic factors influence the probability of disease control, and since patient selection can have a profound impact on results reporting, these issues need to be carefully controlled. A review of patients who are potentially candidates for surgery at the University of Michigan treated with conformal therapy external beam treatment, indicates that these relatively early patients are doing well. These issues will be elaborated upon further during the presentation

  6. Internal pigment cells respond to external UV radiation in frogs.

    Science.gov (United States)

    Franco-Belussi, Lilian; Nilsson Sköld, Helen; de Oliveira, Classius

    2016-05-01

    Fish and amphibians have pigment cells that generate colorful skins important for signaling, camouflage, thermoregulation and protection against ultraviolet radiation (UVR). However, many animals also have pigment cells inside their bodies, on their internal organs and membranes. In contrast to external pigmentation, internal pigmentation is remarkably little studied and its function is not well known. Here, we tested genotoxic effects of UVR and its effects on internal pigmentation in a neotropical frog, Physalaemus nattereri We found increases in body darkness and internal melanin pigmentation in testes and heart surfaces and in the mesenterium and lumbar region after just a few hours of UVR exposure. The melanin dispersion in melanomacrophages in the liver and melanocytes in testes increased after UV exposure. In addition, the amount of melanin inside melanomacrophages cells also increased. Although mast cells were quickly activated by UVR, only longer UVR exposure resulted in genotoxic effects inside frogs, by increasing the frequency of micronuclei in red blood cells. This is the first study to describe systemic responses of external UVR on internal melanin pigmentation, melanomacrophages and melanocytes in frogs and thus provides a functional explanation to the presence of internal pigmentation. © 2016. Published by The Company of Biologists Ltd.

  7. Statistics of Monte Carlo methods used in radiation transport calculation

    International Nuclear Information System (INIS)

    Datta, D.

    2009-01-01

    Radiation transport calculation can be carried out by using either deterministic or statistical methods. Radiation transport calculation based on statistical methods is basic theme of the Monte Carlo methods. The aim of this lecture is to describe the fundamental statistics required to build the foundations of Monte Carlo technique for radiation transport calculation. Lecture note is organized in the following way. Section (1) will describe the introduction of Basic Monte Carlo and its classification towards the respective field. Section (2) will describe the random sampling methods, a key component of Monte Carlo radiation transport calculation, Section (3) will provide the statistical uncertainty of Monte Carlo estimates, Section (4) will describe in brief the importance of variance reduction techniques while sampling particles such as photon, or neutron in the process of radiation transport

  8. External exposure from gamma radiation in uranium mines

    International Nuclear Information System (INIS)

    Thomson, J.E.

    1982-01-01

    Radiation doses received by workers in a high ore grade uranium mine are compared to those of other radiation workers and the need to be able to calculate the exposure rate from an ore body is indicated. The uranium-238 decay chain is presented and particular reference is made to the main gamma emitters and secular equilibrium of the members of the chain. Difficulties in dealing with a self attenuating volume source, in which scattering is important, are pointed out and traditional methods of solution are mentioned. It is shown that in the special case of an infinite ore body a simple solution may be obtained using the energy conservation principle. A straightforward method for calculating the exposure rate from an arbitrarily shaped ore body is given and corrections due to air attenuation, different soil types and possible lack of secular equilibrium are dealt with. The gamma ray spectrum from the ore is discussed with specific reference to the selection of suitable exposure monitors and the calculation of transmission through shields

  9. Calculation of dose conversion factors for doses in the fingernails to organ doses at external gamma irradiation in air

    International Nuclear Information System (INIS)

    Khailov, A.M.; Ivannikov, A.I.; Skvortsov, V.G.; Stepanenko, V.F.; Orlenko, S.P.; Flood, A.B.; Williams, B.B.; Swartz, H.M.

    2015-01-01

    Absorbed doses to fingernails and organs were calculated for a set of homogenous external gamma-ray irradiation geometries in air. The doses were obtained by stochastic modeling of the ionizing particle transport (Monte Carlo method) for a mathematical human phantom with arms and hands placed loosely along the sides of the body. The resulting dose conversion factors for absorbed doses in fingernails can be used to assess the dose distribution and magnitude in practical dose reconstruction problems. For purposes of estimating dose in a large population exposed to radiation in order to triage people for treatment of acute radiation syndrome, the calculated data for a range of energies having a width of from 0.05 to 3.5 MeV were used to convert absorbed doses in fingernails to corresponding doses in organs and the whole body as well as the effective dose. Doses were assessed based on assumed rates of radioactive fallout at different time periods following a nuclear explosion. - Highlights: • Elemental composition and density of nails were determined. • MIRD-type mathematical human phantom with arms and hands was created. • Organ doses and doses to nails were calculated for external photon exposure in air. • Effective dose and nail doses values are close for rotational and soil surface exposures.

  10. Ionizing radiation calculations and comparisons with LDEF data

    Science.gov (United States)

    Armstrong, T. W.; Colborn, B. L.; Watts, J. W., Jr.

    1992-01-01

    In conjunction with the analysis of LDEF ionizing radiation dosimetry data, a calculational program is in progress to aid in data interpretation and to assess the accuracy of current radiation models for future mission applications. To estimate the ionizing radiation environment at the LDEF dosimeter locations, scoping calculations for a simplified (one dimensional) LDEF mass model were made of the primary and secondary radiations produced as a function of shielding thickness due to trapped proton, galactic proton, and atmospheric (neutron and proton cosmic ray albedo) exposures. Preliminary comparisons of predictions with LDEF induced radioactivity and dose measurements were made to test a recently developed model of trapped proton anisotropy.

  11. Calculation of the external dose rate in the spent fuel pool for the case to use compact racks

    International Nuclear Information System (INIS)

    Passos, E.M. dos; Alves, A.S.M.

    1988-01-01

    The possible introduction of compact racks in the spent fuel pool of the Angra 1 Nuclear Power Plant largely inreases its storage capacity, but originates an increase of the gamma radiation sources. The precise evaluation of the effects of the adoption of this option on the external gamma dose rates and also on the thickness of the concrete shielding requires the utilization of sofisticated computer codes (QAD, ANISN), which allow the calculation of the gamma dose rates through thick shielding walls. This paper describes the utilized methodology for the calculation of the modified pool shieldings, showing the obtained results for the Angra 1 NPP case. The gamma dose rate was calculated with the point Kernel model, first analytically, and later through utilization of the tridimensional multigroup QAD computer code. (author) [pt

  12. External gamma radiation survey for oil wellheads in Saudi Arabia

    International Nuclear Information System (INIS)

    Nassar, Rafat M.; Mously, Khalid A.; Cowie, Michael I.

    2008-01-01

    Naturally occurring radioactive material (NORM) is known to be associated with oil and gas extraction. As part of a comprehensive NORM management strategy, Saudi Aramco needed to determine the extent of NORM contamination associated with their oil and gas operations. As part of that strategy, this study focused on external gamma survey of oil producing wellheads at various locations. The study aimed to: 1-) Identify wellheads with elevated gamma radiation dose rate; 2-) Specify the exact locations of the high dose rates on the wellheads; 3-) Identify the radioisotopes responsible for the high dose rates; and 4-) Propose worker protection requirements during maintenance. The majority (∼92%) of the surveyed wellheads showed no enhanced gamma dose-rate above background level. From the remaining ∼8%, only a few wellheads showed dose rates between 1,000-3,700 n Sv/h. The study revealed that NORM contamination tends to accumulate at turns of the pipes, around pipe diameter changes, the joints, the back of valves, and at the base of the wellhead. Also, for a given location, NORM build up on the interior of pipework varies over time and continues to migrate down stream until it reaches the Gas and Oil Separation Plants (GOSP). There NORM is expected to accumulate and reside in the form of sludge. Gamma spectroscopy analysis revealed that 226 Ra and its progeny are responsible for the high radiation dose rates detected. It was concluded that NORM will not pose significant radiation hazards to workers as long as the tubing and piping are not opened. (author)

  13. HADOC: a computer code for calculation of external and inhalation doses from acute radionuclide releases

    International Nuclear Information System (INIS)

    Strenge, D.L.; Peloquin, R.A.

    1981-04-01

    The computer code HADOC (Hanford Acute Dose Calculations) is described and instructions for its use are presented. The code calculates external dose from air submersion and inhalation doses following acute radionuclide releases. Atmospheric dispersion is calculated using the Hanford model with options to determine maximum conditions. Building wake effects and terrain variation may also be considered. Doses are calculated using dose conversion factor supplied in a data library. Doses are reported for one and fifty year dose commitment periods for the maximum individual and the regional population (within 50 miles). The fractional contribution to dose by radionuclide and exposure mode are also printed if requested

  14. Calculating the Effect of External Shading on the Solar Heat Gain Coefficient of Windows

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Christian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shukla, Yash [CEPT Univ., Ahmedabad (India); Rawal, Rajan [CEPT Univ., Ahmedabad (India)

    2017-08-09

    Current prescriptive building codes have limited ways to account for the effect of solar shading, such as overhangs and awnings, on window solar heat gains. We propose two new indicators, the adjusted Solar Heat Gain Coefficient (aSHGC) which accounts for external shading while calculating the SHGC of a window, and a weighted SHGC (SHGCw) which provides a seasonal SHGC weighted by solar intensity. We demonstrate a method to calculate these indices using existing tools combined with additional calculations. The method is demonstrated by calculating the effect of an awning on a clear double glazing in New Delhi.

  15. External radiation assessment in a wet phosphoric acid production plant

    Energy Technology Data Exchange (ETDEWEB)

    Bolivar, J.P.; Perez-Moreno, J.P. [Dept. Fisica Aplicada, Facultad de Ciencias Experimentales, Universidad de Huelva, 21012 Huelva (Spain); Mas, J.L. [Dept. Fisica Aplicada I, Escuela Universitaria Politecnica, Universidad de Sevilla, 41012 Sevilla (Spain)], E-mail: ppmasb@us.es; Martin, J.E.; San Miguel, E.G. [Dept. Fisica Aplicada, Facultad de Ciencias Experimentales, Universidad de Huelva, 21012 Huelva (Spain); Garcia-Tenorio, R. [Dept. Fisica Aplicada II, Escuela Tecnica Superior de Arquitectura, Universidad de Sevilla, 41012 Sevilla (Spain)

    2009-10-15

    226,228}Ra activity concentrations in the material fluxing during the process (the most important radionuclides from the dosimetric point of view) and the external dose rates. Furthermore, any general dependence of the origin of the rock (i.e., on their radioactive contents) on the external effective dose rate measured has not been observed. These latter findings could be a consequence of three effects: (1) a variable radiation shielding at the different points along the process, (2) a changing geometry of irradiation (from a rock pile up to a thin-layered pulp passing through a solid mass inside pipes and deposits), and (3) the existence of a 'memory effect', or background contamination in the installation equipment due to the presence of radionuclide-enriched scales and sludges in pipes and deposits.

  16. Methods for calculating radiation attenuation in shields

    Energy Technology Data Exchange (ETDEWEB)

    Butler, J; Bueneman, D; Etemad, A; Lafore, P; Moncassoli, A M; Penkuhn, H; Shindo, M; Stoces, B

    1964-10-01

    In recent years the development of high-speed digital computers of large capacity has revolutionized the field of reactor shield design. For compact special-purpose reactor shields, Monte-Carlo codes in two- and three dimensional geometries are now available for the proper treatment of both the neutron and gamma- ray problems. Furthermore, techniques are being developed for the theoretical optimization of minimum-weight shield configurations for this type of reactor system. In the design of land-based power reactors, on the other hand, there is a strong incentive to reduce the capital cost of the plant, and economic considerations are also relevant to reactors designed for merchant ship propulsion. In this context simple methods are needed which are economic in their data input and computing time requirements and which, at the same time, are sufficiently accurate for design work. In general the computing time required for Monte-Carlo calculations in complex geometry is excessive for routine design calculations and the capacity of the present codes is inadequate for the proper treatment of large reactor shield systems in three dimensions. In these circumstances a wide range of simpler techniques are currently being employed for design calculations. The methods of calculation for neutrons in reactor shields fall naturally into four categories: Multigroup diffusion theory; Multigroup diffusion with removal sources; Transport codes; and Monte Carlo methods. In spite of the numerous Monte- Carlo techniques which are available for penetration and back scattering, serious problems are still encountered in practice with the scattering of gamma rays from walls of buildings which contain critical facilities and also concrete-lined discharge shafts containing irradiated fuel elements. The considerable volume of data in the unclassified literature on the solution of problems of this type in civil defence work appears not to have been evaluated for reactor shield design. In

  17. Bivariational calculations for radiation transfer in an inhomogeneous participating media

    International Nuclear Information System (INIS)

    El Wakil, S.A.; Machali, H.M.; Haggag, M.H.; Attia, M.T.

    1986-07-01

    Equations for radiation transfer are obtained for dispersive media with space dependent albedo. Bivariational bound principle is used to calculate the reflection and transmission coefficients for such media. Numerical results are given and compared. (author)

  18. Probabilistic approach to external cloud dose calculations using onsite meteorological data

    International Nuclear Information System (INIS)

    Strenge, D.L.; Watson, E.C.; Bander, T.J.; Kennedy, W.E.

    1976-01-01

    A method is described for calculation of external total body and skin doses from accidental atmospheric releases of radionuclides based on hourly onsite meteorological data. The method involves calculation of dose values from a finite size cloud for each hourly observation for a given radionuclide inventory. These values are then used to determine the probability of occurrence of dose levels for specified release times ranging from one hour to 30 days

  19. The Study of External Radiation Dose for Radiation Worker at PRSG-BATAN Serpong

    International Nuclear Information System (INIS)

    Sunarningsih; Mashudi; A Lilik W; Yosep S

    2012-01-01

    The study of External radiation dose for radiation worker at PRSG-BATAN Serpong has been carried out. The sample is taken from the System Reactor division (BSR), Operation Reactor division, (BOR) Safety division UPN, UJM and head of PRSG by setting Thermoluminescence Dosemeter (TLD) on the chest, then is detected by a tool TLD reader model 6600. The aim of this study is to evaluate the occupational exposure dose that has been accepted by the radiation worker for the last five years. The result in average doses at BSR is 0,99 mSv, BOR is 3,27 mSv, at BK is 0,69 mSv and UPN + UJM + head of PRSG is 0,03 mSv. The result highest doses at BSR is 6,58 mSv, BOR is 28,94 mSv, BK is 4,24 mSv, and UPN UJM Head of PRSG is 0,52 mSv. Dose interval radiation worker at PRSG BATAN ttd - 28,98 mSv. To overall the external personal dose acceptant for radiation worker at PRSG BATAN one below maximum permissible dose acceptant that allowed by BAPETEN, that is 20 mSv in average every year during five years. (author)

  20. Comparison of the performance of net radiation calculation models

    DEFF Research Database (Denmark)

    Kjærsgaard, Jeppe Hvelplund; Cuenca, R.H.; Martinez-Cob, A.

    2009-01-01

    . The long-wave radiation models included a physically based model, an empirical model from the literature, and a new empirical model. Both empirical models used only solar radiation as required for meteorological input. The long-wave radiation models were used with model calibration coefficients from......Daily values of net radiation are used in many applications of crop-growth modeling and agricultural water management. Measurements of net radiation are not part of the routine measurement program at many weather stations and are commonly estimated based on other meteorological parameters. Daily...... values of net radiation were calculated using three net outgoing long-wave radiation models and compared to measured values. Four meteorological datasets representing two climate regimes, a sub-humid, high-latitude environment and a semi-arid mid-latitude environment, were used to test the models...

  1. Acute response of the thyroid to external radiation

    International Nuclear Information System (INIS)

    Holten, I.

    1983-01-01

    The study showed that the thyroid gland to a measurable degree is acutely influenced by external radiation. Animal experimental studies suggest that the functional reduction mainly is determined by cell loss in mitosis. The transitory fall in RAIU demonstrated in the present study is hardly explainable by cell death or changes in the TSH concentration alone. Part of the explanation could by vascular changes, which may reduce the iodine uptake, but a direct influence on the enzyme systems of the cells may play a role, too. The fall in TSH concentration in the patients irradiated to the neck apparently is not explainable by cell destruction alone either, and the fine-needle aspirates revealed no signs of any essential cell degeneration or destruction. Thus, it must be concluded that the cause of the early fall in TSH concentration is still unexplained. The changes during and immediately after radiotherpy in the thyroid hormone levels suggested a - possibly transient - damage to the thyroid. However, the follow-up study demonstrated that the thyroid function continued its slow decrease. The study tells little about the genesis of the functional changes. In all essentials, the findings are compatible with cell loss due to mitotic death being the main cause of the functional reduction. The fall in the radioiodine uptake and the transient dises in the TSH concentration can hardly be explained by cell loss alone, and the rise in the TSH concentration during the first four months of the study period, too, suggested the possibility of contributory mechanisms. (author)

  2. Exposures from external radiation and from inhalation of resuspended material

    International Nuclear Information System (INIS)

    Jacob, P.; Roth, P.; Golikov, V.; Balonov, M.; Erkin, V.; Likhtariov, I.; Garger, E.; Kashparov, V.

    1996-01-01

    In the modelling of external exposures due to cesium released during the reactor accident of Chernobyl, gamma dose rates in air over open undisturbed sites are considered to be different according to the unsoluble fraction in the deposit. This is taken into account by forming different classes according to the distance from the Chernobyl NPP. The effect of the different migration behavior in these distance classes on the gamma dose rate in air is found to increase with time. Predictions of gamma dose rates in air are based on measurements of the nuclear weapons tests fallout. Various population groups in the CIS countries are defined according to their place of residence (rural or urban), their occupation or age (indoor resp. outdoor workers, pensioners, school-children, or preschool-children), and their kind of residence (wooden, brick, or multi-storey house). Model results for various population groups are compared with the results of TLD-measurements of individual external exposures. For the calculation of inhalation doses, the new ICRP model for the respiratory tract was used. The dose assessments were conducted for measured size resolved activity distributions of resuspended material, obtained at different locations and for several kinds of agricultural operations. Inhalation doses vary considerably with respect to different kinds of work. Tractor drivers receive much higher doses than other agricultural workers, especially when the cabin window of the tractor is open. Effective doses due to the inhalation of resuspended plutonium are assessed to be a few μSv per initial deposit of one kBq/m 2 . Inhalation doses from 137 Cs are usually smaller by an order of magnitude than the doses from Pu, provided a high solubility is assumed for resuspended Cs

  3. Implementation of a system for external audits beam radiation therapy in terms of reference no

    International Nuclear Information System (INIS)

    Alonso Samper, Jose Luis; Dominguez, Lourdes; Alert Silva, Jose; Alfonso Laguardia, Rodolfo; Larrinaga Cortina, Eduardo; Garcia Yip, Fernando; Rodriguez Machado, Jorge; Morales Lopez, Jorge Luis; Silvestre Patallo, Ileana

    2009-01-01

    This paper presents our experience in implementing a external audit system for radiotherapy beam in no reference conditions with the use of CIRS and a summary of the measurements with him made.This paper presents our experience in implementing a external audit system for radiotherapy beam in no reference conditions with the use of CIRS and a summary of the measurements with him made. Centers were audited with external beam high-energy Co-60, 6 MV and 15 MV and were considered 4 treatment planning systems (TPS): AMEPLAN, Theraplan Plus, Precise Plan and MIRS to calculate doses prescribed in each test case. All measurements were acquired by the audit team using the anthropomorphic phantom CIRS, Semiflex chamber PTW 31010 and PTW electrometer STATES. The implementation and development of the external audits of beams radiotherapy in terms of 'no reference' has brought an improvement in both clinical aspects of treatment and the radiation safety and the quality control, has given us greater confidence and for this reason we believe has become essential. (Author)

  4. Measurement and assessment of doses from external radiations required for revised radiation protection regulations

    International Nuclear Information System (INIS)

    Tsujimura, Norio; Kojima, Noboru; Hayashi, Naomi

    2001-01-01

    Radiation protection regulations based on the 1990 recommendations of ICRP have been revised and will take effect from Apr., 2001. The major changes concerning on the measurement and assessment of doses from external radiations are as follows. (1) Personal dose equivalent and ambient dose equivalent stated in ICRP Publication 74 are introduced as quantities to be measured with personal dosimeters and survey instruments, respectively. (2) For multiple dosimetry for workers, the compartment weighting factors used for a realistic assessment of effective dose are markedly changed. In advance of the introduction of the new radiation protection regulations, the impacts on workplace and personal monitoring for external radiations by these revisions were investigated. The following results were obtained. (1) A new ambient dose equivalent to neutrons is higher with a factor of 1.2 than the old one for moderated fission neutron spectra. Therefore, neutron dose equivalent monitors for workplace monitoring at MOX fuel for facilities should be recalibrated for measurement of the new ambient dose equivalent. (2) Annual effective doses of workers were estimated by applying new calibration factors to readings of personal dosimeters, worn by workers. Differences between effective doses and effective dose equivalents are small for workers engaged in the fabrication process of MOX fuel. (author)

  5. Measurement and assessment of doses from external radiations required for revised radiation protection regulations

    Energy Technology Data Exchange (ETDEWEB)

    Tsujimura, Norio; Kojima, Noboru; Hayashi, Naomi [Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    2001-06-01

    Radiation protection regulations based on the 1990 recommendations of ICRP have been revised and will take effect from Apr., 2001. The major changes concerning on the measurement and assessment of doses from external radiations are as follows. (1) Personal dose equivalent and ambient dose equivalent stated in ICRP Publication 74 are introduced as quantities to be measured with personal dosimeters and survey instruments, respectively. (2) For multiple dosimetry for workers, the compartment weighting factors used for a realistic assessment of effective dose are markedly changed. In advance of the introduction of the new radiation protection regulations, the impacts on workplace and personal monitoring for external radiations by these revisions were investigated. The following results were obtained. (1) A new ambient dose equivalent to neutrons is higher with a factor of 1.2 than the old one for moderated fission neutron spectra. Therefore, neutron dose equivalent monitors for workplace monitoring at MOX fuel for facilities should be recalibrated for measurement of the new ambient dose equivalent. (2) Annual effective doses of workers were estimated by applying new calibration factors to readings of personal dosimeters, worn by workers. Differences between effective doses and effective dose equivalents are small for workers engaged in the fabrication process of MOX fuel. (author)

  6. DEEP code to calculate dose equivalents in human phantom for external photon exposure by Monte Carlo method

    International Nuclear Information System (INIS)

    Yamaguchi, Yasuhiro

    1991-01-01

    The present report describes a computer code DEEP which calculates the organ dose equivalents and the effective dose equivalent for external photon exposure by the Monte Carlo method. MORSE-CG, Monte Carlo radiation transport code, is incorporated into the DEEP code to simulate photon transport phenomena in and around a human body. The code treats an anthropomorphic phantom represented by mathematical formulae and user has a choice for the phantom sex: male, female and unisex. The phantom can wear personal dosimeters on it and user can specify their location and dimension. This document includes instruction and sample problem for the code as well as the general description of dose calculation, human phantom and computer code. (author)

  7. Dose reconstruction in radioactively contaminated areas based on radiation transport calculations and measurements

    International Nuclear Information System (INIS)

    Hiller, Mauritius Michael

    2015-01-01

    The external radiation exposure at the former village of Metlino, Russia, was reconstructed. The Techa river in Metlino was contaminated by water from the Majak plant. The village was evacuated in 1956 and a reservoir lake created. Absorbed doses in bricks were measured and a model of the present-day and the historic Metlino was created for Monte Carlo calculations. By combining both, the air kerma at shoreline could be reconstructed to evaluate the Techa River Dosimetry System.

  8. An Accurate Technique for Calculation of Radiation From Printed Reflectarrays

    DEFF Research Database (Denmark)

    Zhou, Min; Sorensen, Stig B.; Jorgensen, Erik

    2011-01-01

    The accuracy of various techniques for calculating the radiation from printed reflectarrays is examined, and an improved technique based on the equivalent currents approach is proposed. The equivalent currents are found from a continuous plane wave spectrum calculated by use of the spectral dyadic...... Green's function. This ensures a correct relation between the equivalent electric and magnetic currents and thus allows an accurate calculation of the radiation over the entire far-field sphere. A comparison to DTU-ESA Facility measurements of a reference offset reflectarray designed and manufactured...

  9. Assessment of occupational exposures to external radiation - IAEA recommendation 1995

    Energy Technology Data Exchange (ETDEWEB)

    Trousil, J; Plichta, J [CSOD, Praha (Czech Republic); Nikodemova, D [SOD, Bratislava (Slovakia)

    1996-12-31

    The IAEA recommendation contains the guidance on: (1) establishing monitoring programmes; (2) the interpretation of results; (3) records keeping; (4) quality assurance. The objectives for workplace monitoring including the recommended methods are also involved. The choice of personal dosemeter depends not only on the type of radiation but also on the method of interpretation what will be used: (1) photon dosemeters giving information only on the personal dose equivalent Hp(10) - mostly TL or RPL dosemeters are used; (2) photon dosemeter of discriminating type giving, in addition to Hp(10) and Hp(0.07), some indication of radiation type and effective energy and detection of electrons - data which must be known for E calculation -mostly film badge is used; (3) extremity dosemeters giving information on Hp(0.07) - mostly TL dosemeters are used; (4) neutron dosemeters giving information on Hp(10) -track-etch or albedo dosemeters are used. The monitoring service should have quality assurance testing which is an organization`s internal system of procedures and practices which assures the quality of its service. This process may be part of the approval performance testing which is a part of approved procedures carried out be the authoritative organization in regular intervals. The approved monitoring service should perform the dose records keeping which serve the protection of the workers and these data are the part of the Register of the Professional Exposures which is mostly organized by the authoritative body. (J.K.).

  10. Assessment of occupational exposures to external radiation - IAEA recommendation 1995

    International Nuclear Information System (INIS)

    Trousil, J.; Plichta, J.; Nikodemova, D.

    1995-01-01

    The IAEA recommendation contains the guidance on: (1) establishing monitoring programmes; (2) the interpretation of results; (3) records keeping; (4) quality assurance. The objectives for workplace monitoring including the recommended methods are also involved. The choice of personal dosemeter depends not only on the type of radiation but also on the method of interpretation what will be used: (1) photon dosemeters giving information only on the personal dose equivalent Hp(10) - mostly TL or RPL dosemeters are used; (2) photon dosemeter of discriminating type giving, in addition to Hp(10) and Hp(0.07), some indication of radiation type and effective energy and detection of electrons - data which must be known for E calculation -mostly film badge is used; (3) extremity dosemeters giving information on Hp(0.07) - mostly TL dosemeters are used; (4) neutron dosemeters giving information on Hp(10) -track-etch or albedo dosemeters are used. The monitoring service should have quality assurance testing which is an organization's internal system of procedures and practices which assures the quality of its service. This process may be part of the approval performance testing which is a part of approved procedures carried out be the authoritative organization in regular intervals. The approved monitoring service should perform the dose records keeping which serve the protection of the workers and these data are the part of the Register of the Professional Exposures which is mostly organized by the authoritative body. (J.K.)

  11. Prediction of prostate cancer in unscreened men: external validation of a risk calculator.

    Science.gov (United States)

    van Vugt, Heidi A; Roobol, Monique J; Kranse, Ries; Määttänen, Liisa; Finne, Patrik; Hugosson, Jonas; Bangma, Chris H; Schröder, Fritz H; Steyerberg, Ewout W

    2011-04-01

    Prediction models need external validation to assess their value beyond the setting where the model was derived from. To assess the external validity of the European Randomized study of Screening for Prostate Cancer (ERSPC) risk calculator (www.prostatecancer-riskcalculator.com) for the probability of having a positive prostate biopsy (P(posb)). The ERSPC risk calculator was based on data of the initial screening round of the ERSPC section Rotterdam and validated in 1825 and 531 men biopsied at the initial screening round in the Finnish and Swedish sections of the ERSPC respectively. P(posb) was calculated using serum prostate specific antigen (PSA), outcome of digital rectal examination (DRE), transrectal ultrasound and ultrasound assessed prostate volume. The external validity was assessed for the presence of cancer at biopsy by calibration (agreement between observed and predicted outcomes), discrimination (separation of those with and without cancer), and decision curves (for clinical usefulness). Prostate cancer was detected in 469 men (26%) of the Finnish cohort and in 124 men (23%) of the Swedish cohort. Systematic miscalibration was present in both cohorts (mean predicted probability 34% versus 26% observed, and 29% versus 23% observed, both pscreened men, but overestimated the risk of a positive biopsy. Further research is necessary to assess the performance and applicability of the ERSPC risk calculator when a clinical setting is considered rather than a screening setting. Copyright © 2010 Elsevier Ltd. All rights reserved.

  12. External dose-rate conversion factors for calculation of dose to the public

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    This report presents a tabulation of dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides in the environment. This report was prepared in conjunction with criteria for limiting dose equivalents to members of the public from operations of the US Department of Energy (DOE). The dose-rate conversion factors are provided for use by the DOE and its contractors in performing calculations of external dose equivalents to members of the public. The dose-rate conversion factors for external exposure to photons and electrons presented in this report are based on a methodology developed at Oak Ridge National Laboratory. However, some adjustments of the previously documented methodology have been made in obtaining the dose-rate conversion factors in this report. 42 refs., 1 fig., 4 tabs.

  13. Calculation of external-internal flow fields for mixed-compression inlets

    Science.gov (United States)

    Chyu, W. J.; Kawamura, T.; Bencze, D. P.

    1987-01-01

    Supersonic inlet flows with mixed external-internal compressions were computed using a combined implicit-explicit (Beam-Warming-Steger/MacCormack) method for solving the three-dimensional unsteady, compressible Navier-Stokes equations in conservation form. Numerical calculations were made of various flows related to such inlet operations as the shock-wave intersections, subsonic spillage around the cowl lip, and inlet started versus unstarted conditions. Some of the computed results were compared with wind tunnel data.

  14. Calculation of age-dependent effective doses for external exposure using the MCNP code

    International Nuclear Information System (INIS)

    Hung, Tran Van

    2013-01-01

    Age-dependent effective dose for external exposure to photons uniformly distributed in air were calculated. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using the Monte Carlo code MCNP. The calculations were performed for mono-energetic photon sources with source energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10, and 15 years-old and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. From the calculated results, it is shown that the effective doses depend on the body size; the effective doses in younger phantoms are higher than those in the older phantoms, especially below 100 keV. (orig.)

  15. Calculation of age-dependent effective doses for external exposure using the MCNP code

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Tran Van [Research and Development Center for Radiation Technology, ThuDuc, HoChiMinh City (VT)

    2013-07-15

    Age-dependent effective dose for external exposure to photons uniformly distributed in air were calculated. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using the Monte Carlo code MCNP. The calculations were performed for mono-energetic photon sources with source energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10, and 15 years-old and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. From the calculated results, it is shown that the effective doses depend on the body size; the effective doses in younger phantoms are higher than those in the older phantoms, especially below 100 keV. (orig.)

  16. Calculating the diffuse solar radiation in regions without solar radiation measurements

    International Nuclear Information System (INIS)

    Li, Huashan; Bu, Xianbiao; Long, Zhen; Zhao, Liang; Ma, Weibin

    2012-01-01

    Correlations for calculating diffuse solar radiation can be classified into models with global solar radiation (H-based method) and without it (Non-H method). The objective of the present study is to compare the performance of H-based and Non-H methods for calculating the diffuse solar radiation in regions without solar radiation measurements. The comparison is carried out at eight meteorological stations in China focusing on the monthly average daily diffuse solar radiation. Based on statistical error tests, the results show that the Non-H method that includes other readily available meteorological elements gives better estimates. Therefore, it can be concluded that the Non-H method is more appropriate than the H-based one for calculating the diffuse solar radiation in regions without solar radiation measurements. -- Highlights: ► Methods for calculating diffuse solar radiation in regions without solar radiation measurements are investigated. ► Diffuse solar radiation models can be classified into two groups according to global solar radiation. ► Two approaches are compared at the eight meteorological stations in China. ► The method without global solar radiation is recommended.

  17. Numerical calculation of radiation pattern of plasma channel antenna

    International Nuclear Information System (INIS)

    Xia Xinren; Yin Chengyou

    2010-01-01

    The idea of plasma channel antenna (PCA) for high power microwave weapon is presented in this paper. The radiation pattern of PCA is calculated. The directivity functions of general antenna are derived. The near electromagnetic model of PCA is created based on physical circumstances. The electromagnetic fields of PCA and surrounding air in cylindrical coordinate are given. The dispersion equation of PCA is deduced by applying the boundary conditions of electromagnetic fields. The surface wave vector of PCA is achieved. The variations of radiation characteristic with plasma density, antenna length and antenna radius are emphatically discussed. The controllability of PCA's radiation patterns is confirmed. (authors)

  18. Application of maximum values for radiation exposure and principles for the calculation of radiation doses

    International Nuclear Information System (INIS)

    2007-08-01

    The guide presents the definitions of equivalent dose and effective dose, the principles for calculating these doses, and instructions for applying their maximum values. The limits (Annual Limit on Intake and Derived Air Concentration) derived from dose limits are also presented for the purpose of monitoring exposure to internal radiation. The calculation of radiation doses caused to a patient from medical research and treatment involving exposure to ionizing radiation is beyond the scope of this ST Guide

  19. A method for including external feed in depletion calculations with CRAM and implementation into ORIGEN

    International Nuclear Information System (INIS)

    Isotalo, A.E.; Wieselquist, W.A.

    2015-01-01

    Highlights: • A method for handling external feed in depletion calculations with CRAM. • Source term can have polynomial or exponentially decaying time-dependence. • CRAM with source term and adjoint capability implemented to ORIGEN in SCALE. • The new solver is faster and more accurate than the original solver of ORIGEN. - Abstract: A method for including external feed with polynomial time dependence in depletion calculations with the Chebyshev Rational Approximation Method (CRAM) is presented and the implementation of CRAM to the ORIGEN module of the SCALE suite is described. In addition to being able to handle time-dependent feed rates, the new solver also adds the capability to perform adjoint calculations. Results obtained with the new CRAM solver and the original depletion solver of ORIGEN are compared to high precision reference calculations, which shows the new solver to be orders of magnitude more accurate. Furthermore, in most cases, the new solver is up to several times faster due to not requiring similar substepping as the original one

  20. A Route to Chaotic Behavior of Single Neuron Exposed to External Electromagnetic Radiation.

    Science.gov (United States)

    Feng, Peihua; Wu, Ying; Zhang, Jiazhong

    2017-01-01

    Non-linear behaviors of a single neuron described by Fitzhugh-Nagumo (FHN) neuron model, with external electromagnetic radiation considered, is investigated. It is discovered that with external electromagnetic radiation in form of a cosine function, the mode selection of membrane potential occurs among periodic, quasi-periodic, and chaotic motions as increasing the frequency of external transmembrane current, which is selected as a sinusoidal function. When the frequency is small or large enough, periodic, and quasi-periodic motions are captured alternatively. Otherwise, when frequency is in interval 0.778 electromagnetic radiation. The frequency apparently plays a more important role in determining the system behavior.

  1. Radiation effects on relativistic electrons in strong external fields

    International Nuclear Information System (INIS)

    Iqbal, Khalid

    2013-01-01

    The effects of radiation of high energy electron beams are a major issue in almost all types of charged particle accelerators. The objective of this thesis is both the analytical and numerical study of radiation effects. Due to its many applications the study of the self force has become a very active and productive field of research. The main part of this thesis is devoted to the study of radiation effects in laser-based plasma accelerators. Analytical models predict the existence of radiation effects. The investigation of radiation reaction show that in laser-based plasma accelerators, the self force effects lower the energy gain and emittance for moderate energies electron beams and increase the relative energy spread. However, for relatively high energy electron beams, the self radiation and retardation (radiation effects of one electron on the other electron of the system) effects increase the transverse emittance of the beam. The energy gain decreases to even lower value and relative energy spread increases to even higher value due to high radiation losses. The second part of this thesis investigates with radiation reaction in focused laser beams. Radiation effects are very weak even for high energy electrons. The radiation-free acceleration and the simple practical setup make direct acceleration in a focused laser beam very attractive. The results presented in this thesis can be helpful for the optimization of future electron acceleration experiments, in particular in the case of laser-plasma accelerators.

  2. Neoclassical parallel flow calculation in the presence of external parallel momentum sources in Heliotron J

    Energy Technology Data Exchange (ETDEWEB)

    Nishioka, K.; Nakamura, Y. [Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Nishimura, S. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Lee, H. Y. [Korea Advanced Institute of Science and Technology, Daejeon 305-701 (Korea, Republic of); Kobayashi, S.; Mizuuchi, T.; Nagasaki, K.; Okada, H.; Minami, T.; Kado, S.; Yamamoto, S.; Ohshima, S.; Konoshima, S.; Sano, F. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2016-03-15

    A moment approach to calculate neoclassical transport in non-axisymmetric torus plasmas composed of multiple ion species is extended to include the external parallel momentum sources due to unbalanced tangential neutral beam injections (NBIs). The momentum sources that are included in the parallel momentum balance are calculated from the collision operators of background particles with fast ions. This method is applied for the clarification of the physical mechanism of the neoclassical parallel ion flows and the multi-ion species effect on them in Heliotron J NBI plasmas. It is found that parallel ion flow can be determined by the balance between the parallel viscosity and the external momentum source in the region where the external source is much larger than the thermodynamic force driven source in the collisional plasmas. This is because the friction between C{sup 6+} and D{sup +} prevents a large difference between C{sup 6+} and D{sup +} flow velocities in such plasmas. The C{sup 6+} flow velocities, which are measured by the charge exchange recombination spectroscopy system, are numerically evaluated with this method. It is shown that the experimentally measured C{sup 6+} impurity flow velocities do not contradict clearly with the neoclassical estimations, and the dependence of parallel flow velocities on the magnetic field ripples is consistent in both results.

  3. A method to combine three dimensional dose distributions for external beam and brachytherapy radiation treatments for gynecological neoplasms

    International Nuclear Information System (INIS)

    Narayana, V.; Sahijdak, W.M.; Orton, C.G.

    1997-01-01

    Purpose: Radiation treatment of gynecological neoplasms, such as cervical carcinoma, usually combines external radiation therapy with one or more intracavitary brachytherapy applications. Although the dose from external beam radiation therapy and brachytherapy can be calculated and displayed in 3D individually, the dose distributions are not combined. At most, combined point doses are calculated for select points using various time-dose models. In this study, we present a methodology to combine external beam and brachytherapy treatments for gynecological neoplasms. Material and Methods: Three dimensional bio-effect treatment planning to obtain complication probability has been outlined. CT scans of the patient's pelvis with the gynecological applicator in place are used to outline normal tissue and tumor volumes. 3D external beam and brachytherapy treatment plans are developed separately and an external beam dose matrix and a brachytherapy dose matrix was calculated. The dose in each voxel was assumed to be homogeneous. The physical dose in each voxel of the dose matrix was then converted into extrapolated response dose (ERD) based on the linear quadratic model that accounts for the dose per fraction, number of fractions, dose rate, and complete or incomplete repair of sublethal damage (time between fractions). The net biological dose delivered was obtained by summing the ERD grids from external beam and brachytherapy since there was complete repair of sublethal damage between external beam and brachytherapy treatments. The normal tissue complication probability and tumor control probability were obtained using the biological dose matrix based on the critical element model. Results: The outlined method of combining external beam and brachytherapy treatments was implemented on gynecological treatments using an applicator for brachytherapy treatments. Conclusion: Implementation of the biological dose calculation that combine different modalities is extremely useful

  4. Nuclear energy - Radioprotection - Procedure for radiation protection monitoring in nuclear installations for external exposure to weakly penetrating radiation, especially to beta radiation

    International Nuclear Information System (INIS)

    2002-01-01

    This International Standard specifies a procedure for radiation protection monitoring in nuclear installations for external exposure to weakly penetrating radiation, especially to beta radiation and describes the procedure in radiation protection monitoring for external exposure to weakly penetrating radiation in nuclear installations. This radiation comprises β - radiation, β + radiation and conversion electron radiation as well as photon radiation with energies below 15 keV. This International Standard describes the procedure in radiation protection planning and monitoring as well as the measurement and analysis to be applied. It applies to regular nuclear power plant operation including maintenance, waste handling and decommissioning. The recommendations of this International Standard may also be transferred to other nuclear fields including reprocessing, if the area-specific issues are considered. This International Standard may also be applied to radiation protection at accelerator facilities and in nuclear medicine, biology and research facilities

  5. Problems in radiation shielding calculations with Monte Carlo methods

    International Nuclear Information System (INIS)

    Ueki, Kohtaro

    1985-01-01

    The Monte Carlo method is a very useful tool for solving a large class of radiation transport problem. In contrast with deterministic method, geometric complexity is a much less significant problem for Monte Carlo calculations. However, the accuracy of Monte Carlo calculations is of course, limited by statistical error of the quantities to be estimated. In this report, we point out some typical problems to solve a large shielding system including radiation streaming. The Monte Carlo coupling technique was developed to settle such a shielding problem accurately. However, the variance of the Monte Carlo results using the coupling technique of which detectors were located outside the radiation streaming, was still not enough. So as to bring on more accurate results for the detectors located outside the streaming and also for a multi-legged-duct streaming problem, a practicable way of ''Prism Scattering technique'' is proposed in the study. (author)

  6. An implantable radiation dosimeter for use in external beam radiation therapy

    International Nuclear Information System (INIS)

    Scarantino, Charles W.; Ruslander, David M.; Rini, Christopher J.; Mann, Gregory G.; Nagle, H. Troy; Black, Robert D.

    2004-01-01

    An implantable radiation dosimeter for use with external beam therapy has been developed and tested both in vitro and in canines. The device uses a MOSFET dosimeter and is polled telemetrically every day during the course of therapy. The device is designed for permanent implantation and also acts as a radiographic fiducial marker. Ten dogs (companion animals) that presented with spontaneous, malignant tumors were enrolled in the study and received an implant in the tumor CTV. Three dogs received an additional implant in collateral normal tissue. Radiation therapy plans were created for the animals and they were treated with roughly 300 cGy daily fractions until completion of the prescribed cumulative dose. The primary endpoints of the study were to record any adverse events due to sensor placement and to monitor any movement away from the point of placement. No adverse events were recorded. Unacceptable device migration was experienced in two subjects and a retention mechanism was developed to prevent movement in the future. Daily dose readings were successfully acquired in all subjects. A rigorous in vitro calibration methodology has been developed to ensure that the implanted devices maintain an accuracy of ±3.5% relative to an ionization chamber standard. The authors believe that an implantable radiation dosimeter is a practical and powerful tool that fosters individualized patient QA on a daily basis

  7. Pelvic control following external beam radiation for surgical Stage I endometrial adenocarcinoma

    International Nuclear Information System (INIS)

    Rush, Stephen; Gal, David; Potters, Louis; Bosworth, Jay; Lovecchio, John

    1995-01-01

    Purpose: To determine if postoperative external pelvic radiation (EBRT), without vaginal brachytherapy, is sufficient to prevent vaginal cuff and pelvic recurrences in patients with surgical Stage I endometrial adenocarcinoma (ACA). Methods and Materials: The records of 122 patients with surgical Stage I endometrial cancer were reviewed. There were 87 patients with ACA who received EBRT alone and are the subject of this study. Their radiation records were reviewed. All patients underwent exploration, total abdominal hysterectomy, and bilateral salpingo-oophorectomy (TAH BSO), and pelvic and paraaortic lymph node sampling. They were staged according to the FIGO 1988 surgical staging system recommendations. Postoperatively, pelvic EBRT was administered by megavoltage equipment using four fields, to a total dose of 45 to 50.4 Gy. Actuarial survival and disease free survival were calculated according to Kaplan-Meier Method. Results: Twenty-seven patients with Stage IA Grade 1 or 2 ACA with less than one-third myometrial invasion, who did not receive EBRT, and eight patients with histology other than adenocarcinoma (i.e., serous papillary, mucinous, etc.) were not included in the study. For the remaining 87 patients who are in the study group, the median follow-up was 52 months (range: 12-82 months). The 5-year overall survival for these 87 patients was 92%, with a disease-free survival of 83%. There were no tumor recurrences in the upper vagina or in the pelvis. Two patients developed small bowel obstruction (no surgery required), and one patient developed chronic enteritis. Conclusion: Adjuvant external pelvic radiation, without vaginal brachytherapy, prevents pelvic and vaginal cuff recurrences in surgical Stage I endometrial ACA

  8. Review of the radiation protection calculations for the encapsulation plant

    International Nuclear Information System (INIS)

    Ranta-aho, A.

    2008-09-01

    The radiation protection calculations of the encapsulation plant have been carried out with the MCNP5 Monte Carlo code. The focus of the study has been in the parts of the encapsulation plant where the spent fuel is handled after discharge from the transportation casks i.e. the fuel handling cell, the fuel drying station, the canister transfer corridor, the welding chamber, the weld inspection room, the canister buffer storage and the canister lift. The protection against radiation hazard has been mainly designed with thick concrete walls. Additionally, the entrances to the rooms with shielding requirements have been equipped with mazes. The present design excludes doors with shielding properties. The aim of this work was to verify and evaluate the necessary wall thicknesses and the functioning of the mazes in the current design. The calculations verified that for the most parts of the facility, the currently designed walls thicknesses provide adequate protection against radiation from the different spent fuel assembly configurations. Some corrective actions however seem necessary in order to stay clearly below desired radiation limits. For the most parts the functioning of the mazes was inadequate. In some of the cases a different design of the maze will be sufficient action but in some cases the radiation protection can only be secured by heavy doors for practical reasons. (orig.)

  9. Moessbauer radiation dynamical diffraction in crystals being subjected to the action of external variable fields

    International Nuclear Information System (INIS)

    Baryshevskii, V.G.; Skadorov, V.V.

    1986-01-01

    A dynamical theory is developed of the Moessbauer radiation diffraction by crystals being subjected to an variable external field action. Equations describing the dynamical diffraction by nonstationary crystals are obtained. It is shown that the resonant interaction between Moessbauer radiation and shift field induced in the crystal by a variable external field giving rise to an effective conversion of the incident wave into a wave with changed frequency. (author)

  10. Small--radiation-amplitude dynamical voltage model of an irradiated, externally unbiased Josephson tunnel junction

    International Nuclear Information System (INIS)

    McAdory, R.T. Jr.

    1988-01-01

    A theory is presented for the nonequilibrium voltage states of an irradiated Josephson junction shunted by an external resistor but with no external current or voltage biasing. This device, referred to as a free-running Josephson junction, is modeled in a small--radiation-amplitude, deterministic regime extending the previous work of Shenoy and Agarwal. The time-averaged induced voltage is treated as a dynamical variable, the external radiation is modeled as a current source, and the induced junction-radiation vector potential, with and without a mode structure, is treated to first order in the driving currents. A dynamical equation for the time-averaged induced voltage yields a (nonequilibrium) steady-state relation between the time-averaged induced voltage and the incident radiation amplitude valid for a wide range of voltages, including zero. Regions of bistability occur in the voltage--versus--incident-amplitude curves, some of which are dependent on the external resistor. The zero-voltage state breaks down, as the external radiation amplitude is increased, at a critical value of the incident-radiation amplitude inversely proportional to the external resistance

  11. Estimation of effective dose to public from external exposure to natural background radiation in saudi arabia

    International Nuclear Information System (INIS)

    Khalid, A. A.

    2003-01-01

    The effective dose values in sixteen cities in Saudi Arabia due to external exposure to natural radiation were evaluated. These doses are based on natural background components including external exposure to terrestrial radiation and cosmic rays. The importance of evaluating the effective dose to the public due to external exposure to natural background radiation lies in its epidemiological and dosimetric importance and in forming a basis for the assessment of the level of radioactive contamination or pollution in the environment in the future. The exposure to terrestrial radiation was measured using thermoluminescent dosimeters (TLD). The exposure from cosmic radiation was determined using empirical correlation. The values evaluated for the total annual effective dose in all cities were within the world average values. The highest total annual effective dose measured in Al-Khamis city was 802 μSv/y, as compared to 305 μSv/y in Dammam city, which was considered the lowest value

  12. Monitoring and assessment of individual doses of occupationally exposed workers due to external radiation

    International Nuclear Information System (INIS)

    Kitaw, S. T.

    2015-05-01

    Exposure to external radiation occurs in many occupations. Any exposure to ionizing radiation has the tendency to change the biochemical make-up of the human body which may result in biological health effects of ionizing radiation. This study reviews the monitoring and assessment of external radiation doses in industrial radiography using thermoluminescence and direct reading dosimeters. Poor handling procedures such as inadequate engineering control of equipment, safety culture, management, and inadequate assessment and monitoring of doses are the causes of most of the reported cases of exposure to external radiation in industrial radiography. Occupational exposure data in industrial radiography from UNSCEAR report 2008 was discussed and recommendations were made to regulatory authorities, operating organizations and radiographers. (au)

  13. Monte Carlo calculation of dose rate conversion factors for external exposure to photon emitters in soil

    CERN Document Server

    Clouvas, A; Antonopoulos-Domis, M; Silva, J

    2000-01-01

    The dose rate conversion factors D/sub CF/ (absorbed dose rate in air per unit activity per unit of soil mass, nGy h/sup -1/ per Bq kg/sup -1/) are calculated 1 m above ground for photon emitters of natural radionuclides uniformly distributed in the soil. Three Monte Carlo codes are used: 1) The MCNP code of Los Alamos; 2) The GEANT code of CERN; and 3) a Monte Carlo code developed in the Nuclear Technology Laboratory of the Aristotle University of Thessaloniki. The accuracy of the Monte Carlo results is tested by the comparison of the unscattered flux obtained by the three Monte Carlo codes with an independent straightforward calculation. All codes and particularly the MCNP calculate accurately the absorbed dose rate in air due to the unscattered radiation. For the total radiation (unscattered plus scattered) the D/sub CF/ values calculated from the three codes are in very good agreement between them. The comparison between these results and the results deduced previously by other authors indicates a good ag...

  14. External radiation in spinal cord compression in multiple myeloma

    International Nuclear Information System (INIS)

    Rao, G.H.; Ayyagiri, S.; Dutta, T.K.; Gupta, B.D.; Gulati, D.R.

    1978-01-01

    The place of radiotherapy in 14 cases of spinal cord compression in multiple myeloma is outlined. The modalities of treatment and the role of surgery and radiation as decompression methods are emphasised. Complete recovery is seen in 50 percent of the patients in this small group with judicious combination of surgical and/or radiation decompression. Chemotherapy as systematic treatment must be given in all the cases after decompression procedures. It is suggested that reactive oedema after irradiation is only speculative and radiation alone as primary treatment may be recommended in selected cases. (author)

  15. External radiation in spinal cord compression in multiple myeloma

    Energy Technology Data Exchange (ETDEWEB)

    Rao, G H; Ayyagiri, S; Dutta, T K; Gupta, B D; Gulati, D R [Post-Graduate Inst. of Medical Education and Research, Chandigarh (India). Dept. of Radiotherapy

    1978-02-01

    The place of radiotherapy in 14 cases of spinal cord compression in multiple myeloma is outlined. The modalities of treatment and the role of surgery and radiation as decompression methods are emphasised. Complete recovery is seen in 50 percent of the patients in this small group with judicious combination of surgical and/or radiation decompression. Chemotherapy as systematic treatment must be given in all the cases after decompression procedures. It is suggested that reactive oedema after irradiation is only speculative and radiation alone as primary treatment may be recommended in selected cases.

  16. Application of γ field theory based calculation method to the monitoring of mine nuclear radiation environment

    International Nuclear Information System (INIS)

    Du Yanjun; Liu Qingcheng; Liu Hongzhang; Qin Guoxiu

    2009-01-01

    In order to find the feasibility of calculating mine radiation dose based on γ field theory, this paper calculates the γ radiation dose of a mine by means of γ field theory based calculation method. The results show that the calculated radiation dose is of small error and can be used to monitor mine environment of nuclear radiation. (authors)

  17. Fluxon interaction with external rf radiation in Josephson junctions

    DEFF Research Database (Denmark)

    Kivshar, Yuri S.; Olsen, Ole H.; Samuelsen, Mogens Rugholm

    1993-01-01

    . It is shown that due to excitation of a standing linear wave by the driving force, the fluxon motion is strongly influenced by a periodic (averaged) potential similar to the Peierls-Nabarro potential in a discrete chain. This effective potential decreases in the direction of the boundary where the external rf...

  18. Study of the accuracy of radiation field calculations in media

    International Nuclear Information System (INIS)

    Bolyatko, V.V.; Vyrskij, M.Yu.; Ilyushkin, A.I.; Mashkovich, V.P.; Sakharov, V.K.; Stroganov, A.A.

    1981-01-01

    The sensitivity p of the radiation transport calculations to variations of input parameters Xsub(i) is theoretically analyzed, and the calculational errors induced by uncertainties of initial data are evaluated. Two calculational methods are considered: the direct substitution method using the ROZ-5 code and method using the linear perturbation theory. In order to calculate p(Xsub(i)) and bilinear convolutions of the conjugated transport equations the ZAKAT code has been developed. The calculations use the ZAKAT, ROZ-11 and APAMAKO-2F codes. As an example of practical use of the method proposed a shielding composition characteristic for fast reactors was analyzed. A plane monodirectional neutron beam of the BR-10 reactor falls onto a 5-layer stainless steel (1Kh18N10T)-carbon barrier. The sensitivily of the neutron dose absorbed in tissue to the cross sections of all the shielding constituents and to the source and detector representation functions has been calculated. A comparison of the calculations with experimental data proves the validity of the calculational method [ru

  19. Dose control for external radiation; Kawalan dos untuk sinaran luar

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-12-31

    The chapter briefly discussed the following subjects: time and distance limitation, shielding, effects of radiations i.e. alpha particles, beta particles, x-ray, gamma ray, neutron. half value layer, design of shields and operation of shielding.

  20. Normal tissue tolerance to external beam radiation therapy: Adult bone

    International Nuclear Information System (INIS)

    Sargos, P.; Mamou, N.; Dejean, C.; Henriques de Figueiredo, B.; Kantor, G.; Huchet, A.; Italiano, A.

    2010-01-01

    Radiation tolerance for bone tissue has been mostly evaluated with regard to bone fracture. Main circumstances are mandibula osteoradionecrosis, hip and costal fracture, and patent or radiologic fractures in the treated volume. After radiation therapy of bone metastasis, the analysis of related radiation fracture is difficult to individualize from a pathologic fracture. Frequency of clinical fracture is less than 5% in the large series or cohorts and is probably under-evaluated for the asymptomatic lesions. Women older than 50 years and with osteoporosis are probably the main population at risk. Dose-effect relations are difficult to qualify in older series. Recent models evaluating radiations toxicity on diaphysa suggest an important risk after 60 Gy, for high dose-fraction and for a large volume. (authors)

  1. Calculating external doses from contaminated soil with the computer model SOILD

    International Nuclear Information System (INIS)

    Chen, Y.; LePoire, D.; Yu, C.

    1991-01-01

    The SOILD computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The model's four major functional features address (a) dose versus source depth in soil, (b) shielding of clean cover soil, (c) area of contamination, and (d) nonuniform distribution of sources. The model can also adjust doses when there are variations in soil densities for both source and cover soils. It is supported by a data base of ∼500 radionuclides. A sample calculation was performed by SOILD to determine the effective dose equivalent for a uniform source distribution in soil. The soil density was assumed to be 1.6 g/cm 3 , and the source strength was assumed to be 1 pCi/cm 3 . The following radionuclides were studied: 60 C, 131 I, 137+D Cs, 238+D U, and 226+D Ra ('+D' denotes the parent nuclide and daughters)

  2. Radiation shielding calculation for the MOX fuel fabrication plant Melox

    International Nuclear Information System (INIS)

    Lee, Y.K.; Nimal, J.C.; Chiron, M.

    1994-01-01

    Radiation shielding calculation is an important engineering work in the design of the MOX fuel fabrication plant MELOX. Due to the recycle of plutonium and uranium from UO2 spent fuel reprocessing and the large capacity of production (120t HM/yr.), the shielding design requires more attention in this LWR fuel plant. In MELOX, besides several temporary storage facilities of massive fissile material, about one thousand radioactive sources with different geometries, forms, densities, quantities and Pu concentrations, are distributed through different workshops from the PuO 2 powder reception unit to the fuel assembly packing room. These sources, with or without close shield, stay temporarily in different locations, containers and glove boxes. In order to optimize the dimensions, the material and the cost of shield as well as to limit the calculation work in a reasonable engineer-hours, a calculation scheme for shielding design of MELOX is developed. This calculation scheme has been proved to be useful in consideration of the feedback from the evolutionary design and construction. The validated shielding calculations give a predictive but reliable radiation doses information. (authors). 2 figs., 10 refs

  3. Effects of scattering anisotropy approximation in multigroup radiation shielding calculations

    International Nuclear Information System (INIS)

    Altiparmakov, D.

    1983-01-01

    Expansion of the scattering cross sections into Legendre series is the usual way of solving neutron transport problems. Because of the large space gradients of the neutron flux, the effects of that approximation become especially remarkable in the radiation shielding calculations. In this paper, a method taking into account the scattering anisotropy is presented. From the point od view of the accuracy and computing rate, the optimal approximation of the scattering anisotropy is established for the basic protective materials on the basis of simple problem calculations. (author)

  4. The calculation of maximum permissible exposure levels for laser radiation

    International Nuclear Information System (INIS)

    Tozer, B.A.

    1979-01-01

    The maximum permissible exposure data of the revised standard BS 4803 are presented as a set of decision charts which ensure that the user automatically takes into account such details as pulse length and pulse pattern, limiting angular subtense, combinations of multiple wavelength and/or multiple pulse lengths, etc. The two decision charts given are for the calculation of radiation hazards to skin and eye respectively. (author)

  5. Detriment calculations resulting from occupational radiation exposures in Egypt

    International Nuclear Information System (INIS)

    Abdel-Ghani, A.H.

    2000-01-01

    The application of the nominal probability coefficient to evaluate the detriment after the annual occupational exposures of workers from radiation sources and radioactive material have been calculated for workers in medical practices, industrial applications, atomic energy activities and those involved in exploration and mining of radioactive ores and phosphates. The aim of detriment calculations is to provide a foresight for the future occurrence of stochastic effects among the exposed workers. The calculated detriment can be classified into three classes. The first includes workers in diagnostic radiology and atomic energy activities who received the higher doses and consequently represent the higher detriment. The second class comprises workers in radiotherapy and nuclear medicine whose detriment is for times lesser than that of the first class. The third one concerns workers in industrial applications and in exploration and mining of radioactive ores and phosphates, their detriments ten times lesser than that of the second class. The occupational radiation doses are endorsed by the united nation scientific committee on efects of atomic radiation (UNSCEAR) for the period january 1995 to december 1998

  6. The background of external γ radiation in the proportional counters in SAGE experiment

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachev, V.V.

    2003-01-01

    The influence of external γ radiation on the process of 71 Ge-decay counting in proportional counters in SAGE experiment of solar neutrino flux measurement is examined. One determines the systematic error of SAGE result, connected with radon decays inside the air volume surrounding the counters, and the background counting rate of proportional counters from γ radiation of passive and active shield [ru

  7. Examination of the component of the scattered radiation by external monitor chamber using the EGS4

    International Nuclear Information System (INIS)

    Shiota, Y.; Tabushi, K.; Kito, S.

    2005-01-01

    The output beams of the liner accelerator are radiated by an accelerated electron and a dose rate usually fluctuates. The variation affects the shape of a dose distribution in dosimetry. The external monitor chamber is often used for monitoring the variation. Generally the external monitor chamber is set above the water phantom. Therefore, if the irradiation field is small, the scattered radiation due to the external monitor chamber may affect a measurement dose. This work is to examine the component of the scattered radiation generated by external monitor chamber, and to investigate the effect on measurement dose using the EGS4 code and the Klein-Nishina formula. The shapes and the peak energies were corresponding to the spectra of EGS4 and the Klein-Nishina formula. Therefore the main interaction at the external monitor chamber is Compton scatter. The effect of the scattered radiation and the change of the dose distribution were few. However the dose decreased to about 1% under the position of the external monitor chamber. Therefore we should pay the attention to the distance between the external monitor chamber and the measurement chamber. (author)

  8. Mathematical models for calculating radiation dose to the fetus

    International Nuclear Information System (INIS)

    Watson, E.E.

    1992-01-01

    Estimates of radiation dose from radionuclides inside the body are calculated on the basis of energy deposition in mathematical models representing the organs and tissues of the human body. Complex models may be used with radiation transport codes to calculate the fraction of emitted energy that is absorbed in a target tissue even at a distance from the source. Other models may be simple geometric shapes for which absorbed fractions of energy have already been calculated. Models of Reference Man, the 15-year-old (Reference Woman), the 10-year-old, the five-year-old, the one-year-old, and the newborn have been developed and used for calculating specific absorbed fractions (absorbed fractions of energy per unit mass) for several different photon energies and many different source-target combinations. The Reference woman model is adequate for calculating energy deposition in the uterus during the first few weeks of pregnancy. During the course of pregnancy, the embryo/fetus increases rapidly in size and thus requires several models for calculating absorbed fractions. In addition, the increases in size and changes in shape of the uterus and fetus result in the repositioning of the maternal organs and in different geometric relationships among the organs and the fetus. This is especially true of the excretory organs such as the urinary bladder and the various sections of the gastrointestinal tract. Several models have been developed for calculating absorbed fractions of energy in the fetus, including models of the uterus and fetus for each month of pregnancy and complete models of the pregnant woman at the end of each trimester. In this paper, the available models and the appropriate use of each will be discussed. (Author) 19 refs., 7 figs

  9. Modelling of an industrial environment, part 2.: External dose calculation with relevant countermeasures

    International Nuclear Information System (INIS)

    Eged, K.; Kis, Z.; Alvarez-Farizo, B.; Gil, J.; Voigt, G.

    2002-01-01

    The calculation of the collective dose and averted collective dose after applying countermeasures in an industrial environment has been divided in two parts. In the first part (Kis et al. 2002) separate Monte Carlo simulations of photon transport resulted in the air kermas per photon per unit area due to the industrial surfaces contaminated by 1 37C s at specific points using the so-called local approach. In the local approach the air kerma rates due to specific intervention elements at the evaluation locations in the whole environment are determined (Gutierrez et al. 2000). In this way the collective and averted collective dose due to the radiation from a particular intervention element (e.g. the roof of a building) can be obtained. It can, therefore, provide a ranking of the specific intervention elements based on their contribution to collective dose as well. The deposition pattern and the long-term behaviour of deposited radionuclides vary widely in natural circumstances; therefore the number of the photons emitted from the various surfaces per unit area and time can differ significantly. This means the results of the Monte Carlo simulations have to be weighted according to the number of emitted photons so that the actual radiation field can be set up. For this purpose, a dose calculation code has been developed in the framework of the TEMAS project (Gutierrez et al. 2000) which allows to calculate collective doses for different environments. This code has been applied in the present work

  10. Research plan for external radiation protection research 1994/95

    International Nuclear Information System (INIS)

    1994-01-01

    A broad outline of the research financed by the Swedish Radiation Protection Institute but performed outside the Institute. The fiscal year 94/95 is the last year of a three year research plan, and has a budget of about 21 MSEK (close to 3 MUSD). 9.5 MSEK is spent on research connected to nuclear power, 4.1 MSEK on other radiation protection and 3.3 MSEK on participation in the research program of the European Union. Short descriptions of the different areas are given in the report

  11. Assessment of patient radiation protection in external radiotherapy departments after inspections performed by the ASN 2008

    International Nuclear Information System (INIS)

    Franchi, Vincent; Marchal, Carole

    2009-10-01

    This report proposes an assessment of patient radiation protection in external radiotherapy. It is based on inter-regional syntheses of inspections performed by the ASN in external radiotherapy departments during 2008. It addresses 6 main themes related to patient radiation protection: human and material resources, organisation of medical physics, training in patient radiation protection, mastering of equipment (maintenance, internal quality controls of medical devices), safety and care quality management (formalization of the patient care process and definition of responsibilities, patient identity control, treatment preparation, and treatment execution), and risk management (a priori risk analysis, declaration, recording and internal processing of dysfunctions, improvements of care quality and safety management system)

  12. External radiation survey and dose predictions for Rongelap, Utirik, Rongerik, Ailuk, and Wotje Atolls

    International Nuclear Information System (INIS)

    Greenhouse, N.A.; Miltenberger, R.P.

    1977-01-01

    External radiation measurements were made at several atolls in the northern Marshall Islands, which are known or suspected to have been the recipients of tropospheric fallout during the Pacific Testing Programs. Sufficient data were available to ascertain realistic dose predictions for the inhabitants of Rongelap and Utirik Atolls where the 30 year integral doses from external sources exclusive of background radiation were 0.65 and 0.06 rem respectively. These estimates are based on realistic life-style models based on observations of each atoll community. Ailuk and Wotje Atolls were found to be represenatives of regional background radiation levels

  13. Measurement and modeling of external radiation during 1985 from LAMPF [Los Alamos Meson Physics Facility] emissions

    International Nuclear Information System (INIS)

    Bowen, B.M.; Olsen, W.A.; Chen, Ili; Van Etten, D.M.

    1987-11-01

    An array of three portable, pressurized ionization chambers (PICs) continued to measure external radiation levels during 1985 caused by radionuclides emitted from the Los Alamos Meson Physics Facility (LAMPF). A Gaussian-type atmospheric dispersion model, using onsite meteorological and stack release data, was tested during this study. A more complex finite model, which takes into account the contribution of radiation at a receptor from different locations of the passing plume, was also tested. Monitoring results indicate that, as in 1984, a persistent wind up the Rio Grande Valley during the evening and early morning hours is largely responsible for causing the highest external radiation levels to occur to the northeast and north-northeast of LAMPF. However, because of increased turbulent mixing during the day, external radiation levels are generally much less during the day than at night. External radiation levels during 1985 show approximately a 75% reduction over 1984 levels. This resulted from a similar percentage reduction in LAMPF emissions caused by newly implemented emission controls. Comparison of predicted and measured daily external radiation levels indicates a high degree of correlation. The model also gives accurate estimates of measured concentrations over longer time periods. Comparison of predicted and measured hourly values indicates that the model generally tends to overpredict during the day and underpredict at night. 9 refs., 14 figs., 13 tabs

  14. Long-term effects of external radiation on the pituitary and thyroid glands

    International Nuclear Information System (INIS)

    Fuks, Z.; Glatstein, E.; Marsa, G.W.; Bagshaw, M.A.; Kaplan, H.S.

    1976-01-01

    Chronic damage following external irradiation of the normal pituitary and thyroid glands, delivered incidentally during radiotherapy of neoplasms of the head and neck may be more common than has been appreciated in the past. A case of a child who developed pituitary dwarfism 5 1 / 2 years after radiation therapy had been delivered for an embryonal rhabdomyosarcoma of the nasopharynx is described. A review of similar cases from the literature is presented. Likewise, external irradiation of the normal thyroid gland produces a spectrum of radiation-induced syndromes. Clinical damage to the pituitary and thyroid glands is usually manifested months to years after treatment and is preceded by a long subclinical phase. A careful exclusion of these glands from radiation treatment fields is recommended whenever possible. An early detection of endocrine function abnormalities in patients receiving radiation to these glands is desirable, since appropriate treatment may prevent the late deleterious effects of external irradiation of the pituitary and thyroid glands

  15. Methodology of external exposure calculation for reuse of conditional released materials from decommissioning - 59138

    International Nuclear Information System (INIS)

    Ondra, Frantisek; Vasko, Marek; Necas, Vladimir

    2012-01-01

    The article presents methodology of external exposure calculation for reuse of conditional released materials from decommissioning using VISIPLAN 3D ALARA planning tool. Production of rails has been used as an example application of proposed methodology within the CONRELMAT project. The article presents a methodology for determination of radiological, material, organizational and other conditions for conditionally released materials reuse to ensure that workers and public exposure does not breach the exposure limits during scenario's life cycle (preparation, construction and operation of scenario). The methodology comprises a proposal of following conditions in the view of workers and public exposure: - radionuclide limit concentration of conditionally released materials for specific scenarios and nuclide vectors, - specific deployment of conditionally released materials eventually shielding materials, workers and public during the scenario's life cycle, - organizational measures concerning time of workers or public stay in the vicinity on conditionally released materials for individual performed scenarios and nuclide vectors. The above mentioned steps of proposed methodology have been applied within the CONRELMAT project. Exposure evaluation of workers for rail production is introduced in the article as an example of this application. Exposure calculation using VISIPLAN 3D ALARA planning tool was done within several models. The most exposed profession for scenario was identified. On the basis of this result, an increase of radionuclide concentration in conditional released material was proposed more than two times to 681 Bq/kg without no additional safety or organizational measures being applied. After application of proposed safety and organizational measures (additional shielding, geometry changes and limitation of work duration) it is possible to increase concentration of radionuclide in conditional released material more than ten times to 3092 Bq/kg. Storage

  16. Estimated Internal and External Radiation Exposure of Caregivers of Patients With Pediatric Neuroblastoma Undergoing 131I Metaiodobenzylguanidine Therapy: A Prospective Pilot Study.

    Science.gov (United States)

    Han, Sangwon; Yoo, Seon Hee; Koh, Kyung-Nam; Lee, Jong Jin

    2017-04-01

    Current recommendations suggest that family members should participate in the care of children receiving in-hospital I metaiodobenzylguanidine (MIBG) therapy for neuroblastoma. The present study aimed to measure the external radiation exposure and estimate the internal radiation exposure of caregivers during the hospital stay for I MIBG therapy. Caregivers received radiation safety instructions and a potassium iodide solution for thyroid blockade before patient admission. External radiation exposure was determined using a personal pocket dosimeter. Serial 24-hour urine samples were collected from caregivers during the hospital stay. Estimated internal radiation exposure was calculated based on the urine activity. Twelve cases (mean age, 6.2 ± 3.5 years; range, 2-13 years) were enrolled. The mean administered activity was 233.3 ± 74.9 (range, 150.0-350.0) mCi. The mean external radiation dose was 5.8 ± 7.2 (range, 0.8-19.9) mSv. Caregivers of children older than 4 years had significantly less external radiation exposure than those of children younger than 4 years (1.9 ± 1.0 vs 16.4 ± 5.0 mSv; P = 0.012). The mean estimated internal radiation dose was 11.3 ± 10.2 (range, 1.0-29.8) μSv. Caregivers receive both external and internal radiation exposure while providing in-hospital care to children receiving I MIBG therapy for neuroblastoma. However, the internal radiation exposure was negligible compared with the external radiation exposure.

  17. Calculation of the quantities of radiation risk in Japanese population

    International Nuclear Information System (INIS)

    Nakamura, Yuji

    1993-01-01

    The purpose of this study was to reevaluate various kinds of indicators of radiation risks using additive projection and multiplicative projection models, as proposed by ICRP. Total death probability rate (1985) and probability rate of cancer death (1983 to 1987) were used as data base. The following indicators were calculated: total conditional death probability rate and conditional death probability rate; normalized death age probability density and unconditional death probability rate; attributable life-time probability of cancer death; and other risk indicators, including mean loss of life expectancy, reduction of life expectancy, mean annually committed probability of attributable cancer deaths, annual extra probability of cancer death, probability density of the age of death, maximum relative death probability rate (age at maximum relative rate), and probabilistic aging. In terms of calculations of these risk indicators for the comprehensive cancer death, there was no great difference between the Japanese population and ICRP. When calculating according to sites of cancer, calculations of indicators for cancer mortality (or cancer cure rate) in the Japanese population might bedifferent from ICRP's calculation. (N.K.) different from ICRP's calculations. (N.K.)

  18. Calculation of the line shapes of radiators immersed in plasma

    International Nuclear Information System (INIS)

    Hayrapetian, A.S.

    1987-01-01

    This work reports the results of theoretical calculations of line shapes of radiators immersed in plasma. The fluctuating electric field of the plasma perturbs the atomic structure of the immersed ions or atoms. The perturbed line shape is an important diagnostic tool for the temperature and density measurements of plasma. The line-shape calculation here is done by first deriving the line-shape expression, then it is shown that the problem is equivalent to calculating the temperature Green's function of the bound electron. The total Hamiltonian of the system includes the atomic, plasma, and atom-plasma parts. The temperature Green's function is calculated perturbatively by expanding in orders of atom-plasma interaction. By solving a Dyson equation, the dressed Green's functions of the bound electrons are obtained. At this point, the line shape is calculated by an analytic continuation from the complex frequency plane to real line. To derive the atomic electron Green's function, the momentum integral in the self-energy is approximated by a Riemann sum. With this approximation, the algebraic form of the line shape is obtained for an undetermined number of terms in the Riemann sum. Numerical calculation of line shape is done by using this result

  19. Dose conversion coefficients calculated using a series of adult Japanese voxel phantoms against external photon exposure

    International Nuclear Information System (INIS)

    Sato, Kaoru; Endo, Akira; Saito, Kimiaki

    2008-10-01

    This report presents a complete set of conversion coefficients of organ doses and effective doses calculated for external photon exposure using five Japanese adult voxel phantoms developed at the Japan Atomic Energy Agency (JAEA). At the JAEA, high-resolution Japanese voxel phantoms have been developed to clarify the variation of organ doses due to the anatomical characteristics of Japanese, and three male phantoms (JM, JM2 and Otoko) and two female phantoms (JF and Onago) have been constructed up to now. The conversion coefficients of organ doses and effective doses for the five voxel phantoms have been calculated for six kinds of idealized irradiation geometries from monoenergetic photons ranging from 0.01 to 10 MeV using EGS4, a Monte Carlo code for the simulation of coupled electron-photon transport. The dose conversion coefficients are given as absorbed dose and effective dose per unit air-kerma free-in-air, and are presented in tables and figures. The calculated dose conversion coefficients are compared with those of voxel phantoms based on the Caucasian and the recommended values in ICRP74 in order to discuss (1) variation of organ dose due to the body size and individual anatomy, such as position and shape of organs, and (2) effect of posture on organ doses. The present report provides valuable data to study the influence of the body characteristics of Japanese upon the organ doses and to discuss developing reference Japanese and Asian phantoms. (author)

  20. Utilization of MAX and FAX human phantoms for space radiation exposure calculations using HZETRN

    Science.gov (United States)

    Qualls, Garry; Slaba, Tony; Clowdsley, Martha; Blattnig, Steve; Walker, Steven; Simonsen, Lisa

    To estimate astronaut health risk due to space radiation, one must have the ability to calculate, for known radiation environments external to the body, particle spectra, LET spectra, dose, dose equivalent, or gray equivalent that are averaged over specific organs or tissue types. This may be accomplished using radiation transport software and computational human body tissue models. Historically, NASA scientists have used the HZETRN software to calculate radiation transport through both vehicle shielding materials and body tissue. The Computerized Anatomical Man (CAM) and the Computerized Anatomical Female (CAF) body models, combined with the CAMERA software, have been used for body tissue self-shielding calculations. The CAM and CAF, which were developed in 1973 and 1992, respectively, model the 50th percentile U.S. Air Force male and female and are constructed using individual quadric surfaces that combine to form thousands of solid regions that represent specific tissues and structures within the body. In order to transport an external radiation environment to a point within one of the body models using HZETRN, a directional distribution of the tissues surrounding that point is needed. The CAMERA software is used to "ray trace" the CAM and CAF models, providing the thickness of each tissue type traversed along each of a large number of rays originating at a dose point. More recently, R. Kramer of the Departmento de Energia Nuclear, Universidade Federal de Pernambuco in Brazil and his co-workers developed the Male Adult voXel (MAX) model and the Female Adult voXel (FAX). These voxel-based body models were developed using segmented Computed Tomography (CT) scans of adult cadavers, and the quantities and distributions of various body tissues have been adjusted to match those specified in the International Commission on Radiological Protection (ICRP) reference adult male and female. A new set of tools has been developed to facilitate space radiation exposure

  1. Cleanup techniques for Finnish urban environments and external doses from 137Cs - modelling and calculations

    International Nuclear Information System (INIS)

    Moring, M.; Markkula, M.L.

    1997-03-01

    The external doses under various radioactive deposition conditions are assessed and the efficiencies of some simple decontamination techniques (grass cutting, vacuum sweeping, hosing of paved surfaces and roofs, and felling trees) are compared in the study. The present model has been constructed for the Finnish conditions and housing areas, using 137 Cs transfer data from the Nordic and Central European studies and models. The compartment model concerns behaviour and decontamination of 137 Cs in the urban environment under summer conditions. Doses to man have been calculated for wet (light rain) and dry deposition in four typical Finnish building areas: single-family wooden houses, brick terraced-houses, blocks of flats and urban office buildings. (26 refs.)

  2. Present and future prospects of external radiation cancer treatment

    International Nuclear Information System (INIS)

    Valuckas, K. P.; Aleknavicius, E.; Grybauskas, M.

    2004-01-01

    Radiotherapy is the most applicable method in the treatment of cancer patients. Rapid advances in radiotherapy and imaging techniques allow improvement in definition of target margins, volumes, and organs at risk. Conformal radiotherapy using multileaf collimator was introduced towards the end of the 1980s. Further improvements in dose distribution were possible through intensity modulation radiation therapy based on the use of computer-controlled multileaf collimators for creating the desired dose variation inside a radiation field. The dose of definite radiotherapy is limited by dose tolerance of organs or tissues at risk near the target. In the last 50 years radiotherapy modalities achieved rapid developments, particularly in field of treatment planning and dose distribution. The main goal of that development is to apply definite radiotherapy dose to target and minimize normal tissue irradiation, leaving the patient free of treatment related morbidity. (author)

  3. Normal tissue tolerance to external beam radiation therapy: The stomach

    International Nuclear Information System (INIS)

    Oberdiac, P.; Mineur, L.

    2010-01-01

    In the following article, we will discuss general issues relating to acute and late gastric's radiation toxicities. The tolerance of the stomach to complete or partial organ irradiation is more un-appreciated than for most other organs. We consulted the Medline database via PubMed and used the key words gastric - radiotherapy - toxicity. Currently, 60 Gy or less is prescribed in gastric radiation therapy. Acute clinical toxicity symptoms are predominantly nausea and vomiting. Although there is a general agreement that the whole stomach tolerance is for doses of 40 to 45 Gy without unacceptable complication, it is well established that a stomach dose of 35 Gy increases the risk of ulcer complications. (authors)

  4. Normal tissue tolerance to external beam radiation therapy: Skin

    International Nuclear Information System (INIS)

    Ginot, A.; Doyen, J.; Hannoun-Levi, J.M.; Courdi, A.

    2010-01-01

    Acute skin toxicity is frequent during radiation therapy and can lead to temporary arrest of the treatment. Chronic toxicity can occur and conduct to cosmetic problems. Alopecia is the most frequent toxicity concerning hair and is most of the time reversible. Several factors linked to patients influence skin toxicity, such as under-nutrition, old age, obesity, smoking, skin diseases, autoimmune diseases, failure of DNA reparation. Skin, hair and nail toxicities depend also on radiation schedule. Acute toxicity is greater when dose per fraction increases. Chronic and acute toxicities are more often when total dose increases. Under 45 Gy, the risk of severe skin toxicity is low, and begins above 50 Gy. Skin toxicity depends also on the duration of radiotherapy and split course schedules are associated with less toxicities. Irradiation surface seems to influence skin toxicity but interaction is more complex. Reirradiation is often feasible in case of cancer recurrence but with a risk of grade 3-4 toxicity above all in head and neck cancer. The benefit/risk ratio has to be always precisely evaluated. Permanent alopecia is correlated with the follicle dose. Modern techniques of radiation therapy allow to spare skin. (authors)

  5. Calculation and Measurement of Low-Energy Radiative Moller Scattering

    Science.gov (United States)

    Epstein, Charles; DarkLight Collaboration

    2017-09-01

    A number of current nuclear physics experiments have come to rely on precise knowledge of electron-electron (Moller) and positron-electron (Bhabha) scattering. Some of these experiments, having lepton beams on targets containing atomic electrons, use these purely-QED processes as normalization. In other scenarios, with electron beams at low energy and very high intensity, Moller scattering and radiative Moller scattering have such enormous cross-sections that the backgrounds they produce must be understood. In this low-energy regime, the electron mass is also not negligible in the calculation of the cross section. This is important, for example, in the DarkLight experiment (100 MeV). As a result, we have developed a new event generator for the radiative Moller and Bhabha processes, with new calculations that keep all terms of the electron mass. The MIT High Voltage Research Laboratory provides us a unique opportunity to study this process experimentally and compare it with our work, at a low beam energy of 2.5 MeV where the effects of the electron mass are significant. We are preparing a dedicated apparatus consisting of a magnetic spectrometer in order to directly measure this process. An overview of the calculation and the status of the experiment will be presented.

  6. PSA bounces after neoadjuvant androgen deprivation and external beam radiation: Impact on definitions of failure

    International Nuclear Information System (INIS)

    Zietman, Anthony L.; Christodouleas, John P.; Shipley, William U.

    2005-01-01

    Purpose: To determine the characteristics of prostate specific antigen (PSA) bounces after external beam radiation therapy (EBRT) with neoadjuvant androgen deprivation and their impact on definitions of biochemical failure. Methods and Materials: Characteristics of bounce were calculated for all patients treated by EBRT with neoadjuvant androgen deprivation at our institution between 1992 and 1998 (preexclusion analysis). Calculations were repeated for the subgroup that satisfied additional inclusion/exclusion criteria (postexclusion analysis). The percentage of bounces scoring as false positives according to the ASTRO definition of biochemical failure was compared with those for three alternative definitions (Vancouver, Nadir-plus-two, and Nadir-plus-three) using McNemar's tests. Results: Thirty-nine percent (preexclusion cohort) and 56% (postexclusion cohort) of patients demonstrated a PSA bounce. Twenty percent (preexclusion analysis) and 25% (postexclusion analysis) of these bounces scored as biochemical failure according to the ASTRO definition. The Nadir-plus-three definition scored the smallest percentage of bounces as failure, but the difference between this definition and the ASTRO definition reached statistical significance in neither preexclusion nor postexclusion analyses (p ≥ 0.070). Conclusions: A substantial proportion of patients treated by EBRT with neoadjuvant deprivation experienced a PSA bounce. A large percentage of these bounces scored as biochemical failure according to the ASTRO definition. The Nadir-plus-three definition is less vulnerable to this bias

  7. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    2000-01-01

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

  8. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

  9. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    1999-01-01

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

  10. Evaluation of external radiation exposure of personnel involved in veterinary nuclear medicine

    International Nuclear Information System (INIS)

    Komatsubara, N.; Ito, N.; Natsuhori, M.; Sano, T.; Ishikawa, T.; Hatakeyama, S.; Futatsugawa, S.; Terasaki, K.; Hirayama, H.

    2005-01-01

    Veterinary nuclear medicine has been widely applied in the US and Europe, especially for dogs, cats, and horses. The needs of the nuclear medicine in veterinary practice are also growing in Japan. This study was performed in order to make a safety guideline for veterinary nuclear medicine in Japan. Two sorts of well often medically used radionuclide, 18 F and 99m Tc were chosen for evaluating the exposed doses of the veterinarian, the animal owner, and the general public. Air absorption doses around a physical phantom containing radioactive materials ( 18 F or 99m Tc) were measured by glass dosimeters. (Asahi Techno Glass Ltd.) It was verified that the measurement values were corresponding to the calculation values using EGS4. Then, canine pectoral and abdominal mathematical phantom was designed, external radiation exposure of the veterinarian, the animal owner and the public from the phantom containing radioactive materials were calculated by using EGS4. Calculated exposure doses were compared with the dose limit or the dose constraint. (20mSv/yr for the veterinarian: ICRP, 5mSv/yr for the animal owner: IAEA, and 1mSv/yr for the general public: ICRP 2 ). The future integration exposed doses of the animal owner and the public didn't exceed the dose constraint or the dose limit at the release after 24 hours of the radiopharmaceutical administering. In this study, all the calculation conditions were set up on the safety side. Therefore, it is thought that actual exposed doses lower considerably. The safety guideline for the veterinary nuclear medicine in Japan will be established by further application of this type of research. (author)

  11. Delayed effects of external radiation exposure: A brief history

    International Nuclear Information System (INIS)

    Miller, R.W.

    1995-01-01

    Within months of Roentgen's discovery of X rays, severe adverse effects were reported, but not well publicized. As a result, over the next two decades, fluoroscope operators suffered lethal skin carcinomas. Later, case reports appeared concerning leukemia in radiation workers, and infants born with severe mental retardation after their mothers had been given pelvic radiotherapy early in pregnancy. Fluoroscopy and radiotherapy for benign disorders continued to be used with abandon until authoritative reports were published on the adverse effects of ionizing radiation by the U.S. NAS-NRC and the UK MRC in 1956. Meanwhile, exposure to the atomic bombs in Japan had occurred and epidemics of delayed effects began to be recognized among the survivors: cataracts, leukemia and severe mental retardation among newborn infants after intra-uterine exposure. No statistically significant excess of germ-cell genetic effects was detected by six clinical measurements, the F 1 mortality, cytogenetic studies or biochemical genetic studies. Somatic cell effects were revealed by long-lasting chromosomal aberrations in peripheral lymphocytes, and somatic cell mutations were found at the glycophorin A locus in erythrocytes. Molecular biology is a likely focus of new studies based on the function of the gene for ataxia telangiectasia, a disorder in which children have severe, even lethal acute radiation reactions when given conventional doses of radiotherapy for lymphoma, to which they are prone. The tumor registries in Hiroshima and Nagasaki now provide incidence data that show the extent of increases in eight common cancers and no increase in eight others. The possibility of very late effects of A-bomb exposure is suggested by recent reports of increased frequencies of hyperparathyroidism, parathyroid cancers and certain causes of death other than cancer. 88 refs., 1 fig

  12. Dose factors to calculate the radiation exposure due to radioactive waste air from nuclear facilities

    International Nuclear Information System (INIS)

    Brenk, H.D.; Vogt, K.J.

    1977-01-01

    An evaluation of the environmental impact of nuclear plants according to paragraph 45 of the Radiation Protection Directive of the Federal Republic of Germany requires the calculation of dose conversion factors indicating the correlation between the contaminated medium and individual radiation exposure. The present study is to be conceived as a contribution to discussion on this subject. For the determination of radiation exposure caused by the waste air of nuclear plants, models are being specified for computing the dose conversion factors for the external exposure pathways of β-submersion, γ-submersion and γ-radiation from contaminated ground as well as the internal exposure pathways of inhalation and ingestion, which further elaborate and improve the models previously applied, especially as far as the ingestion pathway is concerned, which distinguishes between 6 major food categories. The computer models are applied to those radionuclides which are significan for nuclear emitters, in particular nuclear light-water power stations. The results obtained for the individual exposure pathways and affected organs are specified in the form of tables. For this purpose, calculations were first of all carried out for the so-called 'reference man'. The results can be transferred to population groups with different consumption habits (e.g. vegetarians) by the application of correction factors. The models are capable of being extended with a view to covering other age groups. (orig.) [de

  13. Occupational external radiation exposure in the GDR in 1976

    International Nuclear Information System (INIS)

    Rothe, W.

    1980-01-01

    In 1976 a total of 36,794 occupationally exposed persons were monitored by the National Board of Nuclear Safety and Radiation Protection, using film badges. The monthly over-exposures (more than 4 mGy) totalled 415. In 11 cases the monthly exposure exceeded 30 mGy and 6 annual exposure values were in the range of 50 to 120 mGy. An attempt has been made to assess the annual collective and annual per caput doses for the exposed population as a whole and some subgroups without completely summing up the individual exposure data. (author)

  14. Calculation of radiation dose rates from a spent nuclear fuel shipping cask

    International Nuclear Information System (INIS)

    Chen, S.Y.; Yuan, Y.C.

    1988-01-01

    Radiation doses from a spent nuclear fuel cask are usually from various phases of operations during handling, shipping, and storage of the casks. Assessment of such doses requires knowledge of external radiation dose rates at various locations surrounding a cask. Under current practices, dose rates from gamma photons are usually estimated by means of point- or line-source approaches incorporating the conventional buildup factors. Although such simplified approaches may at times be easy to use, their accuracy has not been verified. For example, those simplified methods have not taken into account influencing factors such as the geometry of the cask and the presence of the ground surface, and the effects of these factors on the calculated dose rates are largely unknown. Moreover, similar empirical equations for buildup factors currently do not exist for neutrons. The objective of this study is to use a more accurate approach in calculating radiation dose rates for both neutrons and gamma photons from a spent fuel cask. The calculation utilizes the more sophisticated transport method and takes into account the geometry of the cask and the presence of the ground surface. The results of a detailed study of dose rates in the near field (within 20 meters) are presented and, for easy application, the cask centerline dose rates are fitted into empirical equations at cask centerline distances up to 2000 meters from the surface of the cask

  15. A case of the hepatic hilar bile duct cancer with external radiation. Efficacy and severe side effect of external radiation therapy

    International Nuclear Information System (INIS)

    Andoh, Hideaki; Yasui, Ouki; Ise, Norihito

    2003-01-01

    Hepatic hilar bile duct cancer was difficult to cure by surgical treatment and its prognosis was very poor. We present the case of non-curative resection of hepatic hilar bile duct cancer, controlled with external radiation. 72 years-old-female, she complained jaundice and diagnosed hepatic hilar bile duct cancer with abdominal ultrasonography. Hepatic hilar resection was performed but curative resection could not be done, because cancer was diffusely spreaded to the hepatic and duodenal ends of the bile duct. After surgery, external radiation (1.8 Gy/day; total 50.4 Gy) was performed. Three months after operation, sometimes, cholangitis was occurred but we could not detect the intrahepatic bile duct dilatation and improved with antibiotics. After seven months, she was dead for sepsis, liver abscess and biliary cirrhosis. From autopsy findings, severe hepatic hilar fibrosis around the irradiation area, stenosis of the hepatico-jejunostomy and portal vein were existed but could not detect the remnant cancer cells. External radiation was sometimes effective, especially for this case. But we should consider the side effect of fibrosis and preventive treatments such as biliary stenting or early biliary drainage. (author)

  16. A case of the hepatic hilar bile duct cancer with external radiation. Efficacy and severe side effect of external radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Andoh, Hideaki; Yasui, Ouki; Ise, Norihito [Akita Univ. (Japan). School of Medicine

    2003-04-01

    Hepatic hilar bile duct cancer was difficult to cure by surgical treatment and its prognosis was very poor. We present the case of non-curative resection of hepatic hilar bile duct cancer, controlled with external radiation. 72 years-old-female, she complained jaundice and diagnosed hepatic hilar bile duct cancer with abdominal ultrasonography. Hepatic hilar resection was performed but curative resection could not be done, because cancer was diffusely spreaded to the hepatic and duodenal ends of the bile duct. After surgery, external radiation (1.8 Gy/day; total 50.4 Gy) was performed. Three months after operation, sometimes, cholangitis was occurred but we could not detect the intrahepatic bile duct dilatation and improved with antibiotics. After seven months, she was dead for sepsis, liver abscess and biliary cirrhosis. From autopsy findings, severe hepatic hilar fibrosis around the irradiation area, stenosis of the hepatico-jejunostomy and portal vein were existed but could not detect the remnant cancer cells. External radiation was sometimes effective, especially for this case. But we should consider the side effect of fibrosis and preventive treatments such as biliary stenting or early biliary drainage. (author)

  17. Outline of manual on measurement and assessment of doses from external radiation

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizawa, Michio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tsujimura, Norio

    2001-03-01

    The external exposure part in the manual for measurement and assessment of doses from external radiation is described since the part is changed in accordance with the revision of the Law Concerning Prevention from Radiation Hazard due to Radioisotopes, Etc. The manual contains general remarks, control of external exposure and its methods, person monitoring, site monitoring, correction of instruments and storage of records. The 2nd and 3rd chapters are described in details, because which are considerably changed together with appendices concerning the operational quantity for measuring external dose, conversion coefficients, and correlations of 3 mm, 1 cm and 70 {mu}m dose equivalents. Making manuals unique to the individual offices, etc. is recommended in compliance with the above manual.(K.H.)

  18. Birth defects in Norway by levels of external and food-based exposure to radiation from Chernobyl

    International Nuclear Information System (INIS)

    Lie, R.T.; Irgens, L.M.; Skjaerven, R.; Reitan, J.B.; Strand, P.; Strand, T.

    1992-01-01

    In Norway, external doses of radiation resulting from fallout from the Chernobyl nuclear accident were estimated from detailed measurements, including soil deposition patterns. Internal doses were estimated from measurements of radioactive cesium in meat and milk supplies. The doses were calculated as average monthly doses for each of 454 municipalities during 36 consecutive months after the accident in spring 1986. Prospectively collected data on all newborns listed in the Medical Birth Registry of Norway who were conceived in the period May 1983-April 1989 were used to assess possible dose-response relations between estimated external and food-based exposures and congenital malformations and some other conditions. A positive association was observed between total radiation dose (external plus food-based) and hydrocephaly, while a negative association was observed for Down's syndrome. However, an important conclusion of the study was that no associations were found for conditions previously reported to be associated with radiation, i.e., small head circumference, congenital cataracts, anencephaly, spina bifida, and low birth weight. Potential sources of bias, including exposure misclassification and incomplete ascertainment of cases, are discussed

  19. The internal radiation dose calculations based on Chinese mathematical phantom

    International Nuclear Information System (INIS)

    Wang Haiyan; Li Junli; Cheng Jianping; Fan Jiajin

    2006-01-01

    The internal radiation dose calculations built on Chinese facts become more and more important according to the development of nuclear medicine. the MIRD method developed and consummated by the society of Nuclear Medicine (America) is based on the European and American mathematical phantom and can't fit Chinese well. The transport of γ-ray in the Chinese mathematical phantom was simulated with Monte Carlo method in programs as MCNP4C. the specific absorbed fraction (Φ) of Chinese were calculated and the Chinese Φ database was created. The results were compared with the recommended values by ORNL. the method was proved correct by the coherence when the target organ was the same with the source organ. Else, the difference was due to the different phantom and the choice of different physical model. (authors)

  20. Recent Progress of the Synchrotron Radiation Calculation Code SPECTRA

    International Nuclear Information System (INIS)

    Tanaka, T.; Kitamura, H.

    2007-01-01

    SPECTRA is a computer software to calculate optical properties of synchrotron radiation (SR) emitted by electrons passing through magnetic devices such as bending magnets, wigglers and undulators. It has been used to design various devices in the SR beamline, such as high heat-load components in the front-end section and optical elements in the optics hutch. In addition, the electron beam quality can be estimated by comparison between the measured and calculated properties of SR. Since the first announcement, numerous improvements have been made to SPECTRA to achieve less computation time with higher numerical accuracy. In addition, a number of functions have been added to follow the user's demand. In this paper, recent progress of SPECTRA is presented and details of the new functions are explained together with several examples

  1. Rectal necrosis following external radiation therapy for carcinoma of the prostate: report of a case

    International Nuclear Information System (INIS)

    Quan, S.H.Q.; O'Kelly, P.J.

    1975-01-01

    Increasing attention is being paid to the use of radiation therapy in the management of primary carcinoma of the prostate. Since 1965, radical radiation therapy has been used at Memorial Hospital to treat primary carcinoma of the prostate. Small primary tumors are treated by implantation with radioactive iodine ( 125 I) seeds and larger tumors considered unsuitable for implantation are treated by external supervoltage beam therapy. Fifty patients had been treated by implantation and 30 by external beam therapy at the time of this report. None of the patients treated by implantation developed rectal symptoms. Proctitis developed in all patients treated by external radiation therapy and in half the patients chronic proctitis ensued, accompanied by the passage of mucus. The constant leaking of mucus through the anal sphincter produces irritation of the skin and intermittent attacks of pruritus ani, a discomfiting sequel. Apart from the proctitis, most patients tolerated treatment well, with one notable exception, in whom rectal necrosis developed. This case is described

  2. A Review of the New European Technical Recommendations for Monitoring Individuals Occupationally Exposed to External Radiation

    International Nuclear Information System (INIS)

    Dijk, J.W.E. van; Alves, J.G.; Ambrosi, P.; Bartlett, D.T.; Currivan, L.; Fantuzzi, E.; Kamenopoulou, V.

    2013-01-01

    This paper reviews the revised Technical Recommendations for Monitoring Individuals Occupationally Exposed to External Radiation as issued by the European Commission as Radiation Protection 160. These recommendations are aimed at all stakeholders in radiation protection dosimetry with an emphasis in the responsible technical staff of approved dosimetry services. This paper briefly touches each Chapter and ends with a more in depth section on the uncertainty evaluation of dose measurements. -- Highlights: ► Recommendations on all aspects of running an approved dosimetry service. ► Radiation protection framework. ► Metrology of personal dosimeters. ► QC and QA of individual monitoring

  3. Reproductive function of animals exposed to low-dose external γ-radiation

    International Nuclear Information System (INIS)

    Izhevskij, P.V.; Krupitskaya, L.I.; Startsev, N.V.

    1993-01-01

    Chronic external γ-radiation effects on the reproductive function were simulated in male rats at doses equivalent to the dose obtained by the persons who participated in the liquidation of the Chernobyl poer plant accident aftereffects and by the population. The incidence of the pre-and postimplantation deaths was found increased in the progeny of males exposed to chronic external γ-irradiation at total doses of 158 and 237 Gy, though no strict dose dependence was observed

  4. External radiation dose and cancer mortality among French nuclear workers. Considering potential confounding by internal radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, L.; Laurent, O.; Samson, E.; Caer-Lorho, S.; Laurier, D.; Leuraud, K. [Institute for Radiological Protection and Nuclear Safety, Fontenay aux Roses (France). Ionizing Radiation Epidemiology Lab.; Laroche, P. [AREVA, Paris (France); Le Guen, B. [EDF, Saint Denis (France)

    2016-11-15

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat a l'Energie Atomique), AREVA NC, or EDF (Electricite de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  5. External radiation dose and cancer mortality among French nuclear workers: considering potential confounding by internal radiation exposure.

    Science.gov (United States)

    Fournier, L; Laurent, O; Samson, E; Caër-Lorho, S; Laroche, P; Le Guen, B; Laurier, D; Leuraud, K

    2016-11-01

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat à l'Energie Atomique), AREVA NC, or EDF (Electricité de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  6. European Randomized Study of Screening for Prostate Cancer Risk Calculator: External Validation, Variability, and Clinical Significance.

    Science.gov (United States)

    Gómez-Gómez, Enrique; Carrasco-Valiente, Julia; Blanca-Pedregosa, Ana; Barco-Sánchez, Beatriz; Fernandez-Rueda, Jose Luis; Molina-Abril, Helena; Valero-Rosa, Jose; Font-Ugalde, Pilar; Requena-Tapia, Maria José

    2017-04-01

    To externally validate the European Randomized Study of Screening for Prostate Cancer (ERSPC) risk calculator (RC) and to evaluate its variability between 2 consecutive prostate-specific antigen (PSA) values. We prospectively catalogued 1021 consecutive patients before prostate biopsy for suspicion of prostate cancer (PCa). The risk of PCa and significant PCa (Gleason score ≥7) from 749 patients was calculated according to ERSPC-RC (digital rectal examination-based version 3 of 4) for 2 consecutive PSA tests per patient. The calculators' predictions were analyzed using calibration plots and the area under the receiver operating characteristic curve (area under the curve). Cohen kappa coefficient was used to compare the ability and variability. Of 749 patients, PCa was detected in 251 (33.5%) and significant PCa was detected in 133 (17.8%). Calibration plots showed an acceptable parallelism and similar discrimination ability for both PSA levels with an area under the curve of 0.69 for PCa and 0.74 for significant PCa. The ERSPC showed 226 (30.2%) unnecessary biopsies with the loss of 10 significant PCa. The variability of the RC was 16% for PCa and 20% for significant PCa, and a higher variability was associated with a reduced risk of significant PCa. We can conclude that the performance of the ERSPC-RC in the present cohort shows a high similitude between the 2 PSA levels; however, the RC variability value is associated with a decreased risk of significant PCa. The use of the ERSPC in our cohort detects a high number of unnecessary biopsies. Thus, the incorporation of ERSPC-RC could help the clinical decision to carry out a prostate biopsy. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Possible inducement of skin basaloma by external alpha radiation

    International Nuclear Information System (INIS)

    Sevcova, M.; Sevc, J.; Thomas, J.

    1975-01-01

    A comparison was made of the latest data on the thickness of the epidermis and the resulting estimate of dose rates to its basal layer with the results of several years of clinical observation in uranium miners exposed over a long term to alpha radiation from a 222 Rn daughter product deposit on the skin. It was found that the average dose equivalent in the basal layer of the epidermis from deposited 222 Rn daughter products was within the region of tens of rem/year even under good hygienic conditions in the uranium mine, and accumulated doses may after several years of exposure reach several thousands rems. In the narrow selection of workers where statistical comparison was possible it appeared that the frequency of observed skin carcinomas, mainly basal carcinomas of the face, neck and hands, is significantly higher in miners working in underground mines as against expected incidence. (B.S.)

  8. Normal tissue tolerance to external beam radiation therapy: Peripheral nerves

    International Nuclear Information System (INIS)

    Henriques de Figueiredo, B.; Dejean, C.; Sargos, P.; Kantor, G.; Huchet, A.; Mamou, N.; Loiseau, H.

    2010-01-01

    Plexopathies and peripheral neuropathies appear progressively and with several years delay after radiotherapy. These lesions are observed principally after three clinical situations: supraclavicular and axillar irradiations for breast cancer, pelvic irradiations for various pathologies and limb irradiations for soft tissue sarcomas. Peripheral nerves and plexus (brachial and lumbosacral) are described as serial structures and are supposed to receive less than a given maximum dose linked to the occurrence of late injury. Literature data, mostly ancient, define the maximum tolerable dose to a threshold of 60 Gy and highlight also a great influence of fractionation and high fraction doses. For peripheral nerves, most frequent late effects are pain with significant differences of occurrence between 50 and 60 Gy. At last, associated pathologies (diabetes, vascular pathology, neuropathy) and associated treatments have probably to be taken into account as additional factors, which may increase the risk of these late radiation complications. (authors)

  9. Radiation Resistance Test of Wireless Sensor Node and the Radiation Shielding Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Liqan; Sur, Bhaskar [Atomic Energy of Canada Limited, Ontario (Canada); Wang, Quan [University of Western Ontario, Ontario (Canada); Deng, Changjian [The University of Electronic Science and Technology, Chengdu (China); Chen, Dongyi; Jiang, Jin [Applied Physics Branch, Ontario (Korea, Republic of)

    2014-08-15

    A wireless sensor network (WSN) is being developed for nuclear power plants. Amongst others, ionizing radiation resistance is one essential requirement for WSN to be successful. This paper documents the work done in Chalk River Laboratories of Atomic Energy of Canada Limited (AECL) to test the resistance to neutron and gamma radiation of some WSN nodes. The recorded dose limit that the nodes can withstand before being damaged by the radiation is compared with the radiation environment inside a typical CANDU (CANada Deuterium Uranium) power plant reactor building. Shielding effects of polyethylene, cadmium and lead to neutron and gamma radiations are also analyzed using MCNP simulation. The shielding calculation can be a reference for the node case design when high dose rate or accidental condition (like Fukushima) is to be considered.

  10. The effective dose equivalent from external and internal radiation

    International Nuclear Information System (INIS)

    Mattsson, Soeren

    1989-01-01

    The various sources of low-level ionizing radiation are discussed and compared in terms of mean effective dose equivalent to man. For the most nonoccupationally exposed individuals, natural sources given the dominating contribution to the effective dose equivalent. The size of this contribution is strongly dependent on human activities. Natural sources contribution on average 2.4 mSV per year, of which half is due to irradiation of lungs and airways from short lived radon daughters present in indoor air. In Sweden this radon daughter contribution is considerably higher and contributes a mean of 3 mSv per year, thus giving a total contribution from natural radiation of about 4 mSV per year. In extreme cases, radon daughter contributions of several hundreds of mSv per year may be reached. Medical exposure, mainly diagnostic X-rays, contributes 0.4-1 mSv per year both in Sweden and as a world average. The testing of nuclear weapons in the atmosphere has given 1-2 mSv to each person in the world as a mean. The contribution from the routine operation of nuclear reactors is insignificant. The reactor accident in Chernobyl resulted in widely varying exposures of the European population. The average for Sweden is estimated to be 0.1 mSv during the first year and about 1 mSv during a 50-year period. For groups of Swedes who eat a considerable amount of game this contribution will be 10 times higher, and for the Lapps who breed reindeer in the most contaminated areas, typical values of 20-70 mSv and extreme values of about 1 Sv may be reached in 50 years. This means that the Chernobyl reactor accident for several years will be their dominating source of irradiation

  11. Calculation of radiation dose received in computed tomography examinations

    International Nuclear Information System (INIS)

    Abed Elseed, Eslam Mustafa

    2014-07-01

    Diagnostic computed tomography (CT) examinations play an important role in the health care of the population. These examination may involve significant irradiation of the patient and probably represent the largest man-made source of radiation exposure for the population. This study was performed to assess the effective dose (ED) received in brain CT examination ( base of skull and cerebrum) and to analyze effective dose distributions among radiological departments under study. The study was performed at Elnileen Medical Center, coverage one CT unit and a sample of 51 patients (25 cerebrum sample and 26 base of skull sample). The following parameters were recorded age, weight, height body mass index (BMI) derived from weight (kg) and height ( m) and exposure factor and CTDI voi , DLP value. The effective dose was measured for brain CT examination. The ED values were calculated from the obtained DLP values using AAPM report No 96 calculation methods. The results of ED values calculated showed that patient exposure were within the normal range of exposure. The mean ED values calculated were 0.35±0.15 for base of skull of brain CT examinations and 0.70±0.32 for cerebrum of brain CT examination, respectively. Further studies are recommended with more number of pa.(Author)

  12. Requirements for the approval of dosimetry services under the Ionising Radiations Regulations 1985: Pt. 1: External radiations

    International Nuclear Information System (INIS)

    1991-01-01

    Guidance for dosimetry services on the requirements for approval by the Health and Safety Executive (HSE) is provided in three parts. This part sets out the procedures and criteria that will be used by HSE in the assessment of dosimetry services seeking approval in relation to external radiations (including accidents). (author)

  13. Modeling Natural Space Ionizing Radiation Effects on External Materials

    Science.gov (United States)

    Alstatt, Richard L.; Edwards, David L.; Parker, Nelson C. (Technical Monitor)

    2000-01-01

    Predicting the effective life of materials for space applications has become increasingly critical with the drive to reduce mission cost. Programs have considered many solutions to reduce launch costs including novel, low mass materials and thin thermal blankets to reduce spacecraft mass. Determining the long-term survivability of these materials before launch is critical for mission success. This presentation will describe an analysis performed on the outer layer of the passive thermal control blanket of the Hubble Space Telescope. This layer had degraded for unknown reasons during the mission, however ionizing radiation (IR) induced embrittlement was suspected. A methodology was developed which allowed direct comparison between the energy deposition of the natural environment and that of the laboratory generated environment. Commercial codes were used to predict the natural space IR environment model energy deposition in the material from both natural and laboratory IR sources, and design the most efficient test. Results were optimized for total and local energy deposition with an iterative spreadsheet. This method has been used successfully for several laboratory tests at the Marshall Space Flight Center. The study showed that the natural space IR environment, by itself, did not cause the premature degradation observed in the thermal blanket.

  14. Basic requirements of dosemeter systems for individual monitoring of external radiation

    International Nuclear Information System (INIS)

    Boehm, J.; Ambrosi, P.

    1985-01-01

    A plea is made for detailed detector independent requirements for dosemeter systems for individual monitoring of external radiation. These requirements should have their origin in the fundamental aspects and concepts of radiation protection for workers, and should be something like a translation of the general principles of individual monitoring into a language easily understandable by producers and users. This work comprises a summary of the general objectives of individual monitoring and discussion of some relevant requirements for dosemeter systems. (orig.) [de

  15. Background of external γ radiation in the proportional counters of the SAGE experiment

    International Nuclear Information System (INIS)

    Gavrin, V.N.; Gorbachev, V.V.

    2003-01-01

    The effect of external γ radiation on the process of counting 71 Ge decays in the proportional counters of the SAGE experiment measuring the solar-neutrino flux is considered. The systematic uncertainty in the SAGE result due to radon decays inside the air volume surrounding the counters is estimated. The background counting rate in the proportional counters that is caused by γ radiation from the enclosing shield is also determined

  16. Measurements of external radiation in United States dwellings

    International Nuclear Information System (INIS)

    Miller, K.M.

    1992-01-01

    The results of a survey of terrestrial gamma radiation levels are reported for the United States. This database represents a total of 1074 measurements in and around 247 different dwellings in several different areas of the country. The absorbed dose rate in air outdoors was found to range between 14 and 118 nGy.h -1 and averaged 46.6. nGy.h -1 , while for indoors it ranged between 12 and 160 nGy.h -1 and averaged 37.6 nGy.h -1 . Apart from regional differences in the terrestrial gamma levels, variations of up to a factor of 2 can be seen in the same geographical area. Variations within a house are typically large, with basement living areas averaging 50% higher than second-floor areas. Houses of full brick construction had average indoor levels 50% higher than those for wood frame houses. The material used for interior wall construction was not found to strongly influence the indoor dose rates except for rooms containing brick, cinder block or stone. For wood frame houses, including those of brick veneer exteriors, a linear regression analysis indicates that the average indoor dose rate can be reasonably well predicted based on a constant, which relates to the building contribution, and a shielding factor for the outdoor dose rate. Using the data collected in this survey and the population weighted mean outdoor absorbed dose rate in air reported for the US, the corresponding mean indoor value is estimated to be 37 nGy.h -1 . This value is in the low end of the range reported for other countries and is about half the estimated worldwide average of 70 nGy.h -1 . (author)

  17. Calculation of the radiative properties of photosynthetic microorganisms

    International Nuclear Information System (INIS)

    Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

    2015-01-01

    A generic methodological chain for the predictive calculation of the light-scattering and absorption properties of photosynthetic microorganisms within the visible spectrum is presented here. This methodology has been developed in order to provide the radiative properties needed for the analysis of radiative transfer within photobioreactor processes, with a view to enable their optimization for large-scale sustainable production of chemicals for energy and chemistry. It gathers an electromagnetic model of light-particle interaction along with detailed and validated protocols for the determination of input parameters: morphological and structural characteristics of the studied microorganisms as well as their photosynthetic-pigment content. The microorganisms are described as homogeneous equivalent-particles whose shape and size distribution is characterized by image analysis. The imaginary part of their refractive index is obtained thanks to a new and quite extended database of the in vivo absorption spectra of photosynthetic pigments (that is made available to the reader). The real part of the refractive index is then calculated by using the singly subtractive Kramers–Krönig approximation, for which the anchor point is determined with the Bruggeman mixing rule, based on the volume fraction of the microorganism internal-structures and their refractive indices (extracted from a database). Afterwards, the radiative properties are estimated using the Schiff approximation for spheroidal or cylindrical particles, as a first step toward the description of the complexity and diversity of the shapes encountered within the microbial world. Finally, these predictive results are confronted to experimental normal-hemispherical transmittance spectra for validation. This entire procedure is implemented for Rhodospirillum rubrum, Arthrospira platensis and Chlamydomonas reinhardtii, each representative of the main three kinds of photosynthetic microorganisms, i.e. respectively

  18. Calculation of the radiative properties of photosynthetic microorganisms

    Science.gov (United States)

    Dauchet, Jérémi; Blanco, Stéphane; Cornet, Jean-François; Fournier, Richard

    2015-08-01

    A generic methodological chain for the predictive calculation of the light-scattering and absorption properties of photosynthetic microorganisms within the visible spectrum is presented here. This methodology has been developed in order to provide the radiative properties needed for the analysis of radiative transfer within photobioreactor processes, with a view to enable their optimization for large-scale sustainable production of chemicals for energy and chemistry. It gathers an electromagnetic model of light-particle interaction along with detailed and validated protocols for the determination of input parameters: morphological and structural characteristics of the studied microorganisms as well as their photosynthetic-pigment content. The microorganisms are described as homogeneous equivalent-particles whose shape and size distribution is characterized by image analysis. The imaginary part of their refractive index is obtained thanks to a new and quite extended database of the in vivo absorption spectra of photosynthetic pigments (that is made available to the reader). The real part of the refractive index is then calculated by using the singly subtractive Kramers-Krönig approximation, for which the anchor point is determined with the Bruggeman mixing rule, based on the volume fraction of the microorganism internal-structures and their refractive indices (extracted from a database). Afterwards, the radiative properties are estimated using the Schiff approximation for spheroidal or cylindrical particles, as a first step toward the description of the complexity and diversity of the shapes encountered within the microbial world. Finally, these predictive results are confronted to experimental normal-hemispherical transmittance spectra for validation. This entire procedure is implemented for Rhodospirillum rubrum, Arthrospira platensis and Chlamydomonas reinhardtii, each representative of the main three kinds of photosynthetic microorganisms, i.e. respectively

  19. A simple and fast physics-based analytical method to calculate therapeutic and stray doses from external beam, megavoltage x-ray therapy.

    Science.gov (United States)

    Jagetic, Lydia J; Newhauser, Wayne D

    2015-06-21

    State-of-the-art radiotherapy treatment planning systems provide reliable estimates of the therapeutic radiation but are known to underestimate or neglect the stray radiation exposures. Most commonly, stray radiation exposures are reconstructed using empirical formulas or lookup tables. The purpose of this study was to develop the basic physics of a model capable of calculating the total absorbed dose both inside and outside of the therapeutic radiation beam for external beam photon therapy. The model was developed using measurements of total absorbed dose in a water-box phantom from a 6 MV medical linear accelerator to calculate dose profiles in both the in-plane and cross-plane direction for a variety of square field sizes and depths in water. The water-box phantom facilitated development of the basic physical aspects of the model. RMS discrepancies between measured and calculated total absorbed dose values in water were less than 9.3% for all fields studied. Computation times for 10 million dose points within a homogeneous phantom were approximately 4 min. These results suggest that the basic physics of the model are sufficiently simple, fast, and accurate to serve as a foundation for a variety of clinical and research applications, some of which may require that the model be extended or simplified based on the needs of the user. A potentially important advantage of a physics-based approach is that the model is more readily adaptable to a wide variety of treatment units and treatment techniques than with empirical models.

  20. Solid cancer mortality associated with chronic external radiation exposure at the French atomic energy commission and nuclear fuel company.

    Science.gov (United States)

    Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

    2011-07-01

    Studies of nuclear workers make it possible to directly quantify the risks associated with ionizing radiation exposure at low doses and low dose rates. Studies of the CEA (Commissariat à l'Energie Atomique) and AREVA Nuclear Cycle (AREVA NC) cohort, currently the most informative such group in France, describe the long-term risk to nuclear workers associated with external exposure. Our aim is to assess the risk of mortality from solid cancers among CEA and AREVA NC nuclear workers and its association with external radiation exposure. Standardized mortality ratios (SMRs) were calculated and internal Poisson regressions were conducted, controlling for the main confounding factors [sex, attained age, calendar period, company and socioeconomic status (SES)]. During the period 1968-2004, there were 2,035 solid cancers among the 36,769 CEA-AREVA NC workers. Cumulative external radiation exposure was assessed for the period 1950-2004, and the mean cumulative dose was 12.1 mSv. Mortality rates for all causes and all solid cancers were both significantly lower in this cohort than in the general population. A significant excess of deaths from pleural cancer, not associated with cumulative external dose, was observed, probably due to past asbestos exposure. We observed a significant excess of melanoma, also unassociated with dose. Although cumulative external dose was not associated with mortality from all solid cancers, the central estimated excess relative risk (ERR) per Sv of 0.46 for solid cancer mortality was higher than the 0.26 calculated for male Hiroshima and Nagasaki A-bomb survivors 50 years or older and exposed at the age of 30 years or older. The modification of our results after stratification for SES demonstrates the importance of this characteristic in occupational studies, because it makes it possible to take class-based lifestyle differences into account, at least partly. These results show the great potential of a further joint international study of

  1. Acute care of radioactively contaminated or externally radiated personnel at nuclear power plants

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Practical advice is given concerning the treatment of persons injure at nuclear power plant accidents, in particular accidents resulting in contamination or external radiation of man. The folder is primarily directed to persons responsible for the local plannning and supervision of emergency care at the power plant. (L.E.)

  2. External evaluation of the Radiation Therapy Oncology Group brachial plexus contouring protocol: several issues identified

    International Nuclear Information System (INIS)

    Min, Myo; Carruthers, Scott; Zanchetta, Lydia; Roos, Daniel; Keating, Elly; Shakeshaft, John; Baxi, Siddhartha; Penniment, Michael; Wong, Karen

    2014-01-01

    The aims of the study were to evaluate interobserver variability in contouring the brachial plexus (BP) using the Radiation Therapy Oncology Group (RTOG)-approved protocol and to analyse BP dosimetries. Seven outliners independently contoured the BPs of 15 consecutive patients. Interobserver variability was reviewed qualitatively (visually by using planning axial computed-tomography images and anteroposterior digitally reconstructed radiographs) and quantitatively (by volumetric and statistical analyses). Dose–volume histograms of BPs were calculated and compared. We found significant interobserver variability among outliners in both qualitative and quantitative analyses. These were most pronounced for the T1 nerve roots on visual inspection and for the BP volume on statistical analysis. The BP volumes were smaller than those described in the RTOG atlas paper, with a mean volume of 20.8cc (range 11–40.7 cc) compared with 33±4cc (25.1–39.4cc). The average values of mean dose, maximum dose, V60Gy, V66Gy and V70Gy for patients treated with conventional radiotherapy and IMRT were 42.2Gy versus 44.8Gy, 64.5Gy versus 68.5Gy, 6.1% versus 7.6%, 2.9% versus 2.4% and 0.6% versus 0.3%, respectively. This is the first independent external evaluation of the published protocol. We have identified several issues, including significant interobserver variation. Although radiation oncologists should contour BPs to avoid dose dumping, especially when using IMRT, the RTOG atlas should be used with caution. Because BPs are largely radiologically occult on CT, we propose the term brachial-plexus regions (BPRs) to represent regions where BPs are likely to be present. Consequently, BPRs should in principle be contoured generously.

  3. External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

    Energy Technology Data Exchange (ETDEWEB)

    Abo-Elmagd, M [National Institute for Standard, Radiation Measurements Department, P.O. Box 136 Giza code no. 12211 (Egypt); Metwally, S M [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); Elmongy, S A [Atomic Energy Authority, Nuclear Safety, Cairo (Egypt); Salama, E [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); El-Fiki, S A [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt)

    2006-02-15

    Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43{mu}Sv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively.

  4. External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

    International Nuclear Information System (INIS)

    Abo-Elmagd, M.; Metwally, S.M.; Elmongy, S.A.; Salama, E.; El-Fiki, S.A.

    2006-01-01

    Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43μSv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively

  5. Internal radiation dose calculations with the INREM II computer code

    International Nuclear Information System (INIS)

    Dunning, D.E. Jr.; Killough, G.G.

    1978-01-01

    A computer code, INREM II, was developed to calculate the internal radiation dose equivalent to organs of man which results from the intake of a radionuclide by inhalation or ingestion. Deposition and removal of radioactivity from the respiratory tract is represented by the Internal Commission on Radiological Protection Task Group Lung Model. A four-segment catenary model of the gastrointestinal tract is used to estimate movement of radioactive material that is ingested, or swallowed after being cleared from the respiratory tract. Retention of radioactivity in other organs is specified by linear combinations of decaying exponential functions. The formation and decay of radioactive daughters is treated explicitly, with each radionuclide in the decay chain having its own uptake and retention parameters, as supplied by the user. The dose equivalent to a target organ is computed as the sum of contributions from each source organ in which radioactivity is assumed to be situated. This calculation utilizes a matrix of dosimetric S-factors (rem/μCi-day) supplied by the user for the particular choice of source and target organs. Output permits the evaluation of components of dose from cross-irradiations when penetrating radiations are present. INREM II has been utilized with current radioactive decay data and metabolic models to produce extensive tabulations of dose conversion factors for a reference adult for approximately 150 radionuclides of interest in environmental assessments of light-water-reactor fuel cycles. These dose conversion factors represent the 50-year dose commitment per microcurie intake of a given radionuclide for 22target organs including contributions from specified source organs and surplus activity in the rest of the body. These tabulations are particularly significant in their consistent use of contemporary models and data and in the detail of documentation

  6. External beam radiation for retinoblastoma: Results, patterns of failure, and a proposal for treatment guidelines

    International Nuclear Information System (INIS)

    Hernandez, J. Carlos; Brady, Luther W.; Shields, Jerry A.; Shields, Carol L.; Potter, Patrick de; Karlsson, Ulf L.; Markoe, Arnold M.; Amendola, Beatriz E.; Singh, Arun

    1996-01-01

    Purpose: To analyze treatment results and patterns of failure following external beam radiation for retinoblastoma and propose treatment guidelines according to specific clinical variables. Methods and Materials: We analyzed 27 patients (34 eyes) with retinoblastoma who received external beam radiation as initial treatment at Hahnemann University Hospital from October 1980 to December 1991 and have been followed for at least 1 year. Of the 34 eyes, 14 were Groups I-II (Reese-Ellsworth classification), 7 were Group III, and 13 were Groups IV-V. Doses ranged from 34.5-49.5 Gy (mean 44.3 Gy, median 45 Gy) in 1.5-2.0 Gy fractions generally delivered through anterior and lateral wedged pair fields. Results: At a mean follow up of 35.2 months (range 12-93 months), local tumor control was obtained in 44% (15 out of 34) of eyes with external beam radiation alone. Salvage therapy (plaque brachytherapy, cryotherapy, and/or photocoagulation) controlled an additional 10 eyes (29.5%), so that overall ocular survival has been 73.5%. Local tumor control with external beam radiotherapy alone was obtained in 78.5% (11 out of 14) of eyes in Groups I-II, but in only 20% (4 out of 20) of eyes in Groups III-V. A total of 67 existing tumors were identified prior to treatment in the 34 treated eyes and local control with external beam radiation alone was obtained in 87% (46 out of 53) of tumors measuring 15 mm or less and in 50% (7 out of 14) of tumors measuring more than 15 mm. When analyzing patterns of failure in the 19 eyes that relapsed, a total of 28 failure sites were identified and consisted of progression of vitreous seeds in seven instances (25% of failure sites) recurrences from previously existing tumors in 10 instances (36% of failure sites) and development of new tumors in previously uninvolved retina in 11 instances (39% of failure sites). Conclusions: 1) We find that external beam radiation to a dose of 45 Gy in fractions of 1.5 to 2.0 Gy provides adequate tumor control

  7. Doses from external and internal radiation in Norway during the first year after the Chernobyl accident

    International Nuclear Information System (INIS)

    Strand, P.; Kjoelaas, G.; Reitan, J.B.; Strand, T.; Berthelsen, T.; Selnaes, T.D.

    1990-01-01

    In this article the estimation of monthly doses from external radiation from internal radiation due to ingestion of contaminated food is reported. The monthly doses is estimated for each municipality in Norway for the first 13 months after the Chernobyl accident (from May 1986 to June 1987). The estimation which has been elaborated from an extensive data material, shows that the dose rates from external radiation due to the Chernobyl fallout were for the country as a whole three times higher in the first month after the accident (May 1986) compared with the twelfth month (April 1987). The doses received from intake of radiocesium through food were small in the first three months, but reached almost the double of the doses from the external radiation the 9th month. The reduction in the dose from external radiation was primarily due to the physical half life of radiocesium and washout. The increase in the doses from radiocesium through intake of food was due to the time required for radiocesium to enter the food chain and the biokinetics of radiocesium in humans. There is no significant correlation between the ground activity levels and the activity levels observed in the food which is consumed in the same area. The average internal dose in the first year after the Chernobyl accident was estimated to 0.110 ± 0.006 mSv and the external dose to 0.070 ± 0.007 mSv as an average for the whole country. 13 refs., 3 figs., 4 tabs

  8. Probe And Enhancement Of SBS Based Phonons In Infrared Fibers Using Waveguide Coupled External Radiation

    Science.gov (United States)

    Yu, Chung; Chong, Yat C.; Fong, Chee K.

    1989-06-01

    Interaction of GHz and MHz radiation with CO2 laser propagation in a silver halide fiber using sBs based phonon coupling is furthet investigated. The external signal serves to both probe and enhance laser generated sBs phonons in the fiber. Efficient coupling of microwave radiation into the fiber is accomplished by placing the fiber in a hollow metallic waveguide, designed and constructed to transmit the dominant mode in the 0.9-2.0 GHz band. MHz radiation is conveniently coupled into the fiber using the guided microwave radiation as carrier. Phonon emissions from the fiber under CO2 laser pumping are first established on a spectrum analyzer; low frequency generators ale then tuned to match these frequencies and their maximum interaction recorded. Such interactions are systematically studied by monitoring the amplitude and waveform of the reflected and transmitted laser pulse at various power levels and frequencies of the externally coupled radiation. A plot of reflected laser power versus incident laser power reveals a distinct sBs generated phonon threshold. Variouslaunch directions of the GHz and MHz radiation with respect to the direction of laser propagation are realized to verify theory governing sBs interactions. The MHz radiation and its associated phonons in the fiber are convenient tools for probing sBs related phenomenon in infrared fibers.

  9. Decreased sexual capacity after external radiation therapy for prostate cancer impairs quality of life

    International Nuclear Information System (INIS)

    Helgason, Asgeir R.; Fredrikson, Mats; Adolfsson, Jan; Steineck, Gunnar

    1995-01-01

    Purpose: The aim of this study was to assess to what extent patients treated with radiation therapy for prostate cancer experience change in sexual functioning and to what extent this effects quality of life. Methods and Materials: Information was provided by 53 men treated with radiation therapy for localized prostate cancer. Assessment was made with the ''Radiumhemmets Scale of Sexual Functioning,'' which measures sexual desire, erectile capacity, orgasm, and to what extent a decrease in any of these aspects of sexual functioning affects quality of life. Function before treatment was assessed retrospectively. Results: Sexual desire diminished among 77% after treatment. The erection stiffness decreased in 77%. Before external radiation therapy, 66% had an erection usually sufficient for intercourse. Half of the men lost this ability after treatment. Of those retaining orgasm after treatment, 47% reported a decreased orgasmic pleasure and 91% a reduced ejaculation volume. Of all men, 50% reported that quality of life had decreased much or very much due to a decline in the erectile capacity following external radiation therapy. Conclusion: The results of the present study indicate that external radiation therapy for prostate cancer is associated with a reduction in sexual desire, erectile capacity, and orgasm functions. In a majority of patients this reduces quality of life. Previously, we may have underestimated the importance an intact sexual function has for the quality of life in this patient category of elderly men

  10. SPACETRAN, Radiation Leakage from Cylinder with ANISN Flux Calculation

    International Nuclear Information System (INIS)

    Cramer, S.N.; Solomito, M.

    1974-01-01

    1 - Nature of physical problem solved: SPACETRAN is designed to calculate the energy-dependent total flux or some proportional quantity such as kerma, due to the radiation leakage from the surface of a right-circular cylinder at detector positions located at arbitrary distances from the surface. The assumptions are made that the radiation emerging from the finite cylinder has no spatial dependence and that a vacuum surrounds the cylinder. 2 - Method of solution: There are three versions of the program in the code package. SPACETRAN-I uses the surface angular fluxes calculated by the discrete ordinates SN code ANISN, as input. SPACETRAN-II assumes that the surface angular flux for all energies can be represented as a function (Cos(PHI))**N, where PHI is the angle between surface outward normal and radiation direction, and N is an integer specified by the user. For both versions the energy group structure and the number and location of detectors is arbitrary. The flux (or response function) for a given energy group at some detection point is computed by summing the contributions from each surface area element over the entire surface. The surface area elements are defined by input data. SPACETRAN-III uses surface angular fluxes from DOT-3. SPACETRAN-I handles contributions either from a cylinder 'end' or 'side', so the total contributions must be obtained by adding the results of separate end and side runs. ANISN angular fluxes are specified for discrete directions. In general, the direction between the detector and contributing area will not exactly coincide with one of these discrete directions. In this case, the ANISN angular flux for the 'closest' discrete direction is used to approximate the contribution to the detector. SPACETRAN-II handles contributions from both the side and end of a cylinder in a single run. Since the assumed angular distribution is specified by a continuous function, it is not necessary to perform the angle selection described above. For

  11. Measurement and modeling of external radiation during 1984 from LAMPF atmospheric emissions

    International Nuclear Information System (INIS)

    Bowen, B.M.; Olsen, W.A.; Van Etten, D.; Chen, I.

    1986-07-01

    An array of three portable, pressurized ionization chambers (PICs) measured short-term external radiation levels produced by air activation products from the Los Alamos Meson Physics Facility (LAMPF). The monitoring was at the closet offsite location, 700-900 m north and northeast of the source, and across a large, deep canyon. A Gaussian-type atmospheric dispersion model, using onsite meteorological and stack release data, was tested during their study. Monitoring results indicate that a persistent, local up-valley wind during the evening and early morning hours is largely responsible for causing the highest radiation levels to the northeast and north-northeast of LAMPF. Comparison of predicted and measured daily external radiation levels indicates a high degree of correlation. The model also gives accurate estimates of measured concentrations over longer periods of time

  12. Determination of the radiation dose to the body due to external radiation

    International Nuclear Information System (INIS)

    Drexler, G.; Eckerl, H.

    1985-01-01

    Section 63 of the Radiation Protection Ordinance defines the basic requirement, determination of radiation dose to the body. The determination of dose equivalents for the body is the basic step in practical monitoring of dose equivalents or dose limits with regard to individuals or population groups, both for constant or varying conditions of exposure. The main field of monitoring activities is the protection of persons occupationally exposed to ionizing radiation. Conversion factors between body doses and radiation quantities are explained. (DG) [de

  13. Measurement and evaluation of the external radiation level at reactor Kartini

    International Nuclear Information System (INIS)

    Atok Suhartanto; Suparno

    2013-01-01

    Measurement and evaluation of external radiation level at reactor Kartini in 2012 has been done. The purpose of this activity is to know the external radiation level as a result of the radioactive or radiation source usage, toward the operational of limit condition. The measurement is using survey meter Inspector 11086, factor of calibration 0.991 mR/h, at 9 locations is: Control room area, Thermal column facilities, Demineralizer, Beamport radiography facilities, bulk shielding Deck, Subcritical facilities, Reactor hall, Deck reactor and on the surface of reactor water tank . The highest room average measurement result in 9 working areas for 12 months continuously are at the reactor tank location is between 13.05±1.09 (xlO -2 mSv/hour) to 16.80±1.40 (x10 -2 mSv/hour), and the lowest measurement result in 1 location (control room) is 0.02±0.005 (x10 -2 mSv/hour) to 0.035±0.009 (x10 -2 mSv/hour). The Kartini reactor is involved in the control area which has potentially contaminated and has radiation exposure at the level of 6 mSv/year. Radiation Protection Officer that work in interval will received radiation exposure dosage of 8.4 mSv/year. This dosage is still below the Below Dosage Value which is recommended by, BAPETEN decree No, 4, 2013 about Protection and Radiation Safety in Nuclear Energy Application at 20 mSv/year. The result of the evaluation above shows that the external radiation which occurred in each area is still below the operational of limit condition that is written on the Kartini reactor safety analysis report, on document number: C7/05/B2/LAK/2010, revision 7. So that the workplace is safe for work monitored. (author)

  14. A calculation and measurement of the flow field in a steam condenser external to the tube nest

    International Nuclear Information System (INIS)

    Stastny, M.; Feistauer, M.

    1989-01-01

    The suggested physical and mathematical model is used to solve the flow of steam normal to the cooling tubes of condenser cross-sections in the region external to the nests. Numerical calculations are carried out by means of a multipurpose system of programmes for the finite element method and a programme for the boundary layer calculation. The results of the calculations are compared with measurements on the condenser of a 500MW steam turbine. The calculations of the flow field in a double pass condenser for the 1000MW saturated steam turbine are described. (author)

  15. External radiation in Dolon village due to local fallout from the first USSR atomic bomb test in 1949.

    Science.gov (United States)

    Imanaka, Tetsuji; Fukutani, Satoshi; Yamamoto, Masayoshi; Sakaguchi, Aya; Hoshi, Masaharu

    2006-02-01

    Dolon village, located about 60 km from the border of the Semipalatinsk Nuclear Test Site, is known to be heavily contaminated by local fallout from the first USSR atomic bomb test in 1949. External radiation in Dolon was evaluated based on recent 137Cs data in soil and calculation of temporal change in the fission product composition. After fitting a log-normal distribution to the soil data, a 137Cs deposition of 32 kBq m-2, which corresponds to the 90th-percentile of the distribution, was tentatively chosen as a value to evaluate the radiation situation in 1949. Our calculation indicated that more than 95% of the cumulative dose for 50 y had been delivered within 1 y after the deposition. The resulting cumulative dose for 1 y after the deposition, normalized to the initial contamination containing 1 kBq m-2 of 137Cs, was 15.6 mGy, assuming a fallout arrival time of 3 h and a medium level of fractionation. Finally, 0.50 Gy of absorbed dose in air was derived as our tentative estimate for 1-year cumulative external dose in Dolon due to local fallout from the first USSR test in 1949.

  16. Electromagnetic radiation damping of charges in external gravitational fields (weak field, slow motion approximation). [Harmonic coordinates, weak field slow-motion approximation, Green function

    Energy Technology Data Exchange (ETDEWEB)

    Rudolph, E [Max-Planck-Institut fuer Physik und Astrophysik, Muenchen (F.R. Germany)

    1975-01-01

    As a model for gravitational radiation damping of a planet the electromagnetic radiation damping of an extended charged body moving in an external gravitational field is calculated in harmonic coordinates using a weak field, slowing-motion approximation. Special attention is paid to the case where this gravitational field is a weak Schwarzschild field. Using Green's function methods for this purpose it is shown that in a slow-motion approximation there is a strange connection between the tail part and the sharp part: radiation reaction terms of the tail part can cancel corresponding terms of the sharp part. Due to this cancelling mechanism the lowest order electromagnetic radiation damping force in an external gravitational field in harmonic coordinates remains the flat space Abraham Lorentz force. It is demonstrated in this simplified model that a naive slow-motion approximation may easily lead to divergent higher order terms. It is shown that this difficulty does not arise up to the considered order.

  17. The calculation of collective radiation exposure arising from discharges of activity into an estuary or sea in the British Isles

    International Nuclear Information System (INIS)

    Maul, P.R.

    1982-04-01

    A model is described for the calculation of collective radiation exposure for releases of activity to an estuary or sea. The model is based on methods described by the CEC with the main exposure pathways being via the ingestion of seafood and external exposure on beaches. For tritium the most important pathway arises from the transfer of activity from the marine to the atmospheric environment. The model is best suited for calculations for fairly long-lived nuclides which do not become dispersed globally and for which the seafood ingestion pathway is dominant. Dose calculations for short-lived nuclides or nuclides where the external exposure pathway can be important will have greater uncertainty associated with them. A computer code CODAR is being developed which incorporates this model. (author)

  18. Generalized concept for the estimation of body dose for radiation workers exposed to external #betta#-rays

    International Nuclear Information System (INIS)

    Piesch, E.; Boehm, J.; Heinzelmann, M.

    1983-01-01

    In radiation protection monitoring the need exists for an estimation of body dose due to external #betta#-rays, for instance if the #betta#-dose rate at the working area is expected to be high according to the data of source activity or room contamination, the indicated dose values of a personal dosemeter exceed the operational limit for the organ or tissue depth of interest, or a person was exposed to a significant dose. On behalf of the Federal Ministry of the Interior, Federal Republic of Germany, a guideline is now under preparation which offers a standardized concept of the estimation of #betta#-doses in personnel monitoring. The calculation models discussed here will be used as a basis for any case of external #betta#-irradiation where, in connection with the German Radiation Protection Ordinance, the ICRP dose equivalent limits are reached or the dosemeter readings are not representative for an individual exposure. The generalized concept discussed in the paper relates to: the calculation of #betta#-dose on the basis of source activity or spectral particle fluence and takes into account the special cases of point sources, area sources and volume sources; the estimation of body dose on the basis of calculated data or measured results from area or personnel monitoring, taking into account the dose equivalent in different depths of tissue, in particular the dose equivalent to the skin, the lens of the eye and other organs; and finally the estimation of skin dose due to the contamination of the skin surface. Basic reference data are presented in order to estimate the dose equivalent of interest which varies significantly in the #betta#-radiation field as a function of the maximum #betta#-energy, distance to the source, size of the source, activity per area for surface contamination and activity per volume for air contamination

  19. Safety of {sup 90}Y Radioembolization in Patients Who Have Undergone Previous External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Marnix G.E.H. [Division of Interventional Radiology, Stanford University School of Medicine, Stanford, California (United States); Department of Radiology and Nuclear Medicine, University Medical Center Utrecht (Netherlands); Abdelmaksoud, Mohamed H.K. [Division of Interventional Radiology, Stanford University School of Medicine, Stanford, California (United States); Chang, Daniel T.; Eclov, Neville C.; Chung, Melody P.; Koong, Albert C. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Louie, John D. [Division of Interventional Radiology, Stanford University School of Medicine, Stanford, California (United States); Sze, Daniel Y., E-mail: dansze@stanford.edu [Division of Interventional Radiology, Stanford University School of Medicine, Stanford, California (United States)

    2013-10-01

    Purpose: Previous external beam radiation therapy (EBRT) is theoretically contraindicated for yttrium-90 ({sup 90}Y) radioembolization (RE) because the liver has a lifetime tolerance to radiation before becoming vulnerable to radiation-induced liver disease. We analyzed the safety of RE as salvage treatment in patients who had previously undergone EBRT. Methods and Materials: Between June 2004 and December 2010, a total of 31 patients who had previously undergone EBRT were treated with RE. Three-dimensional treatment planning with dose–volume histogram (DVH) analysis of the liver was used to calculate the EBRT liver dose. Liver-related toxicities including RE-induced liver disease (REILD) were reviewed and classified according to Common Terminology Criteria for Adverse Events version 4.02. Results: The mean EBRT and RE liver doses were 4.40 Gy (range, 0-23.13 Gy) and 57.9 Gy (range, 27.0-125.9 Gy), respectively. Patients who experienced hepatotoxicity (≥grade2; n=12) had higher EBRT mean liver doses (7.96 ± 8.55 Gy vs 1.62 ± 3.39 Gy; P=.037), the only independent predictor in multivariate analysis. DVH analysis showed that the fraction of liver exposed to ≥30 Gy (V30) was the strongest predictor of hepatotoxicity (10.14% ± 12.75% vs 0.84% ± 3.24%; P=.006). All patients with V30 >13% experienced hepatotoxicity. Fatal REILD (n=2) occurred at the 2 highest EBRT mean liver doses (20.9 Gy and 23.1 Gy) but also at the highest cumulative liver doses (91.8 Gy and 149 Gy). Conclusions: Prior exposure of the liver to EBRT may lead to increased liver toxicity after RE treatment, depending on fractional liver exposure and dose level. The V30 was the strongest predictor of toxicity. RE appears to be safe for the treatment of hepatic malignancies only in patients who have had limited hepatic exposure to prior EBRT.

  20. Radiation doses from radiation sources of neutrons and photons by different computer calculation

    International Nuclear Information System (INIS)

    Siciliano, F.; Lippolis, G.; Bruno, S.G.

    1995-12-01

    In the present paper the calculation technique aspects of dose rate from neutron and photon radiation sources are covered with reference both to the basic theoretical modeling of the MERCURE-4, XSDRNPM-S and MCNP-3A codes and from practical point of view performing safety analyses of irradiation risk of two transportation casks. The input data set of these calculations -regarding the CEN 10/200 HLW container and dry PWR spent fuel assemblies shipping cask- is frequently commented as for as connecting points of input data and understanding theoric background are concerned

  1. Effects of external radiation fields on line emission—application to star-forming regions

    Energy Technology Data Exchange (ETDEWEB)

    Chatzikos, Marios; Ferland, G. J. [University of Kentucky, Lexington, KY 40506 (United States); Williams, R. J. R. [AWE plc, Aldermaston, Reading RG7 4PR (United Kingdom); Porter, Ryan [Department of Physics and Astronomy and Center for Simulational Physics, University of Georgia, Athens, GA 30602-2451 (United States); Van Hoof, P. A. M., E-mail: mchatzikos@gmail.com [Royal Observatory of Belgium, Avenue Circulaire 3, B-1180 Uccle (Belgium)

    2013-12-20

    A variety of astronomical environments contain clouds irradiated by a combination of isotropic and beamed radiation fields. For example, molecular clouds may be irradiated by the isotropic cosmic microwave background, as well as by a nearby active galactic nucleus. These radiation fields excite atoms and molecules and produce emission in different ways. We revisit the escape probability theorem and derive a novel expression that accounts for the presence of external radiation fields. We show that when the field is isotropic the escape probability is reduced relative to that in the absence of external radiation. This is in agreement with previous results obtained under ad hoc assumptions or with the two-level system, but can be applied to complex many-level models of atoms or molecules. This treatment is in the development version of the spectral synthesis code CLOUDY. We examine the spectrum of a Spitzer cloud embedded in the local interstellar radiation field and show that about 60% of its emission lines are sensitive to background subtraction. We argue that this geometric approach could provide an additional tool toward understanding the complex radiation fields of starburst galaxies.

  2. External gamma radiation dose studies in the proposed uranium mining areas of Andhra Pradesh, India

    International Nuclear Information System (INIS)

    Reddy, P.; Reddy, K.; Reddy, C.; Reddy, K.

    2006-01-01

    Natural radiation sources contribute the largest component to the total effective dose received by the human population. Among these sources, natural background gamma radiation shares a noteworthy amount. The present study aims at the establishment of baseline environmental gamma radiation data in the environs of proposed uranium mining areas of Andhra Pradesh, India. To this end, a systematic study has been undertaken using Thermoluminescence (T.L.) dosimeters and G.M. (Geiger - Muller) tube based survey meter. These levels are estimated both indoors and outdoors in the study area covering about 23 villages surrounding the proposed mining sites. The estimated external gamma radiation levels (air kerma) varied from 0.605 to 4.39 mGy.y -1 . The mean indoor to outdoor radiation level ratio is found to be 1.1 ± 0.1. The estimated mean equivalent doses due to external background radiation in the villages of the study area range from 1.03 to 2.83 mSv.y -1 with a mean of 2.34 ± 0.39 mSv.y -1 . (authors)

  3. Application of maximum values for radiation exposure and principles for the calculation of radiation dose

    International Nuclear Information System (INIS)

    2000-01-01

    The guide sets out the mathematical definitions and principles involved in the calculation of the equivalent dose and the effective dose, and the instructions concerning the application of the maximum values of these quantities. further, for monitoring the dose caused by internal radiation, the guide defines the limits derived from annual dose limits (the Annual Limit on Intake and the Derived Air Concentration). Finally, the guide defines the operational quantities to be used in estimating the equivalent dose and the effective dose, and also sets out the definitions of some other quantities and concepts to be used in monitoring radiation exposure. The guide does not include the calculation of patient doses carried out for the purposes of quality assurance

  4. Application of maximum values for radiation exposure and principles for the calculation of radiation dose

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The guide sets out the mathematical definitions and principles involved in the calculation of the equivalent dose and the effective dose, and the instructions concerning the application of the maximum values of these quantities. further, for monitoring the dose caused by internal radiation, the guide defines the limits derived from annual dose limits (the Annual Limit on Intake and the Derived Air Concentration). Finally, the guide defines the operational quantities to be used in estimating the equivalent dose and the effective dose, and also sets out the definitions of some other quantities and concepts to be used in monitoring radiation exposure. The guide does not include the calculation of patient doses carried out for the purposes of quality assurance.

  5. External radiation doses from deposed fly ash with a content of 40K, 226Ra and 232Th

    International Nuclear Information System (INIS)

    Hedemann Jensen, P.

    1991-12-01

    Fly ash from coal fired power plants might be used as filling material below buildings used for habitation. The fly ash content of the radionuclides of potassium, thorium and radium can cause external exposure of the inhabitants to γ radiation emitted during the radioactive decay of those radionuclides. Methods for calculation of the γ dose rate in air at indoor and outdoor positions are described. The dependence of the air dose rate on the vertical and horizontal dimensions of the fly ash material and on the thickness of a covering layer of soil or sand is analysed. The effective annual dose to inhabitants are calculated for typical Danish housing conditions with the buildings placed on a layer of fly ash of infinite vertical and horizontal dimensions and covered by soil or sand of varying thickness. (au) 10 refs

  6. Flux and brightness calculations for various synchrotron radiation sources

    International Nuclear Information System (INIS)

    Weber, J.M.; Hulbert, S.L.

    1991-11-01

    Synchrotron radiation (SR) storage rings are powerful scientific and technological tools. The first generation of storage rings in the US., e.g., SURF (Washington, D.C.), Tantalus (Wisconsin), SSRL (Stanford), and CHESS (Cornell), revolutionized VUV, soft X-ray, and hard X-ray science. The second (present) generation of storage rings, e.g. the NSLS VUV and XRAY rings and Aladdin (Wisconsin), have sustained the revolution by providing higher stored currents and up to a factor of ten smaller electron beam sizes than the first generation sources. This has made possible a large number of experiments that could not performed using first generation sources. In addition, the NSLS XRAY ring design optimizes the performance of wigglers (high field periodic magnetic insertion devices). The third generation storage rings, e.g. ALS (Berkeley) and APS (Argonne), are being designed to optimize the performance of undulators (low field periodic magnetic insertion devices). These extremely high brightness sources will further revolutionize x-ray science by providing diffraction-limited x-ray beams. The output of undulators and wigglers is distinct from that of bending magnets in magnitude, spectral shape, and in spatial and angular size. Using published equations, we have developed computer programs to calculate the flux, central intensity, and brightness output bending magnets and selected wigglers and undulators of the NSLS VUV and XRAY rings, the Advanced Light Source (ALS), and the Advanced Photon Source (APS). Following is a summary of the equations used, the graphs and data produced, and the computer codes written. These codes, written in the C programming language, can be used to calculate the flux, central intensity, and brightness curves for bending magnets and insertion devices on any storage ring

  7. Evaluation of multimodality treatment for advanced pancreatic cancer. Special reference to intraoperative vs. external radiation therapy

    International Nuclear Information System (INIS)

    Wakasugi, Hideyuki; Funakoshi, Akihiro; Seo, Yousuke; Iguchi, Haruo; Wada, Susumu

    1999-01-01

    Intraoperative radiation therapy (IORT)+postoperative external beam radiation therapy (ERT) with chemotherapy and ERT alone with chemotherapy have been performed in our hospital for unresectable, especially locally advanced, pancreatic cancer. We compared the former method with the latter. Chemotherapy was performed together with radiation, using 5-FU, CDDP, and MMC. IORT+ERT was successful in only half of the treated patients, while ERT alone was successful in almost all of the patients. As a result, the doses of radiation were often shorter in patients treated by the former method compared to the latter method. Both methods, when completed for locally advanced pancreatic cancer (stage IVa), produced good effects on tumor markers, tumor size and pain. Furthermore, the latter method was better than the former in improving the survival time and quality of life (QOL). Therefore, ERT is a practical and useful method for patients with locally advanced pancreatic cancer. (author)

  8. An examination of human factors in external beam radiation therapy: Findings and implications

    International Nuclear Information System (INIS)

    Henriksen, K.; Kaye, R.D.; Jones, R.E. Jr.; Morisseau, D.S.; Persensky, J.J.

    1994-01-01

    To better understand the contributing factors to human error in external beam radiation therapy, the US Nuclear Regulatory Commission has undertaken a series of human factors evaluations. A team of human factors specialists, assisted by a panel of radiation oncologists, medical physicists, and radiation technologists, conducted visits to 24 radiation oncology departments at community hospitals, university centers, and free-standing clinics. A function and task analysis was initially performed to guide subsequent evaluations in the areas of human-system interfaces, procedures, training and qualifications, and organizational policies and practices. Representative findings and implications for improvement are discussed within the context of a dynamic model which holds that misadministration likely results from the unanticipated interaction of several necessary but singly insufficient conditions

  9. Volume-based geometric modeling for radiation transport calculations

    International Nuclear Information System (INIS)

    Li, Z.; Williamson, J.F.

    1992-01-01

    Accurate theoretical characterization of radiation fields is a valuable tool in the design of complex systems, such as linac heads and intracavitary applicators, and for generation of basic dose calculation data that is inaccessible to experimental measurement. Both Monte Carlo and deterministic solutions to such problems require a system for accurately modeling complex 3-D geometries that supports ray tracing, point and segment classification, and 2-D graphical representation. Previous combinatorial approaches to solid modeling, which involve describing complex structures as set-theoretic combinations of simple objects, are limited in their ease of use and place unrealistic constraints on the geometric relations between objects such as excluding common boundaries. A new approach to volume-based solid modeling has been developed which is based upon topologically consistent definitions of boundary, interior, and exterior of a region. From these definitions, FORTRAN union, intersection, and difference routines have been developed that allow involuted and deeply nested structures to be described as set-theoretic combinations of ellipsoids, elliptic cylinders, prisms, cones, and planes that accommodate shared boundaries. Line segments between adjacent intersections on a trajectory are assigned to the appropriate region by a novel sorting algorithm that generalizes upon Siddon's approach. Two 2-D graphic display tools are developed to help the debugging of a given geometric model. In this paper, the mathematical basis of our system is described, it is contrasted to other approaches, and examples are discussed

  10. Measurement and Calculation of Gamma Radiation from HWZPR Reactor

    International Nuclear Information System (INIS)

    Jalali, Majid

    2006-01-01

    HWZPR is a research reactor with natural uranium fuel, D 2 O moderator and graphite reflector with maximum power of 100 W. It is a suitable means for theoretical research and heavy water reactor experiments. Neutrons from the core participate in different nuclear reactions by interactions with fuel, moderator, graphite and the concrete around the reactor. The results of these interactions are the production of prompt gammas in the environment. Useful information is gained by the reactor gamma spectrum measurement from point of view of relative quantity and energy distribution of direct and scattered radiations. Reactor gamma ray spectrum has been gathered in different places around the reactor by HPGe detector. In analysis of these spectra, 1 H(n,γ) 2 H, 16 O(n,n'γ) 16 O, 2 H(n,γ) 3 H and 238 U(n,γ) 239 U reactions occurring in reactor moderator and fuel, are important. The measured spectrum has been primarily estimated by the MCNP code. There is agreement between the code and the experiments in some points. The scattered gamma rays from 27 Al (n,γ) 28 Al reaction in the reactor tank, are the most among the gammas scattered in the reactor environment. Also the dose calculations by MCNP code show that 72% of gamma dose belongs to the energy range 3-11 MeV from reactor gamma spectrum and the danger of exposure from the reactor high-energy photons is serious. (author)

  11. Benchmark experiment to verify radiation transport calculations for dosimetry in radiation therapy; Benchmark-Experiment zur Verifikation von Strahlungstransportrechnungen fuer die Dosimetrie in der Strahlentherapie

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Franziska [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany)

    2016-11-01

    Monte Carlo simulations are regarded as the most accurate method of solving complex problems in the field of dosimetry and radiation transport. In (external) radiation therapy they are increasingly used for the calculation of dose distributions during treatment planning. In comparison to other algorithms for the calculation of dose distributions, Monte Carlo methods have the capability of improving the accuracy of dose calculations - especially under complex circumstances (e.g. consideration of inhomogeneities). However, there is a lack of knowledge of how accurate the results of Monte Carlo calculations are on an absolute basis. A practical verification of the calculations can be performed by direct comparison with the results of a benchmark experiment. This work presents such a benchmark experiment and compares its results (with detailed consideration of measurement uncertainty) with the results of Monte Carlo calculations using the well-established Monte Carlo code EGSnrc. The experiment was designed to have parallels to external beam radiation therapy with respect to the type and energy of the radiation, the materials used and the kind of dose measurement. Because the properties of the beam have to be well known in order to compare the results of the experiment and the simulation on an absolute basis, the benchmark experiment was performed using the research electron accelerator of the Physikalisch-Technische Bundesanstalt (PTB), whose beam was accurately characterized in advance. The benchmark experiment and the corresponding Monte Carlo simulations were carried out for two different types of ionization chambers and the results were compared. Considering the uncertainty, which is about 0.7 % for the experimental values and about 1.0 % for the Monte Carlo simulation, the results of the simulation and the experiment coincide.

  12. Tips for deciphering and quick calculation of radiation spectra

    Science.gov (United States)

    Bondarenco, M. V.

    2018-04-01

    Radiation spectra from ultra-relativistic electrons in thin [Tll lf(ω)] and thick [Tgg lf(ω)] targets are discussed. The method of simplified averaging is described by examples of Landau-Pomeranchuk-Migdal effect and radiation at doughnut scattering. General infrared and ultraviolet asymptotic properties of radiation spectra are discussed.

  13. Accidents and incidents with external and/or internal radiation-exposure

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    An individual radiation exposure accident is an unexpected and unintended event which gives rise to an overexposure (external or internal). By overexposure one means all external or internal exposure which could lead to the exceeding of the regulatory norms. Going beyond these limits does not always produce pathological manifestations. The term radiological accident is, in practice, used only when there is an occurrence of some biological or clinical response, or when some therapeutic action is required. A radio-exposure accident can occur: within or from a nuclear power plant or from a center employing ionizing radiation. These are the most frequent; and during the transport of radioactive materials. These are exceptional events. The tanks and containers used in the transport of highly radioactive substances are exhaustively studied for their resistance to accidents, and the conditions of transport determined by very strict national and international regulations. The transport of substances of low radioactivity (labelled molecules, radiopharmaceuticals...) carries only minor risks

  14. SOILD: A computer model for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil

    International Nuclear Information System (INIS)

    Chen, S.Y.; LePoire, D.; Yu, C.; Schafetz, S.; Mehta, P.

    1991-01-01

    The SOLID computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The models four major functional features address (1) dose versus source depth in soil, (2) shielding of clean cover soil, (3) area of contamination, and (4) nonuniform distribution of sources. The model is also capable of adjusting doses when there are variations in soil densities for both source and cover soils. The model is supported by a data base of approximately 500 radionuclides. 4 refs

  15. Can multiparametric MRI replace Roach equations in staging prostate cancer before external beam radiation therapy?

    International Nuclear Information System (INIS)

    Girometti, Rossano; Signor, Marco Andrea; Pancot, Martina; Cereser, Lorenzo; Zuiani, Chiara

    2016-01-01

    Purpose: To investigate the agreement between Roach equations (RE) and multiparametric magnetic resonance imaging (mpMRI) in assessing the T-stage of prostate cancer (PCa). Materials and methods: Seventy-three patients with biopsy-proven PCa and previous RE assessment prospectively underwent mpMRI on a 3.0T magnet before external beam radiation therapy (EBRT). Using Cohen’s kappa statistic, we assessed the agreement between RE and mpMRI in defining the T-stage (≥T3 vs.T ≤ 2) and risk category according to the National comprehensive cancer network criteria (≤intermediate vs. ≥high). We also calculated sensitivity and specificity for ≥T3 stage in an additional group of thirty-seven patients with post-prostatectomy histological examination (mpMRI validation group). Results: The agreement between RE and mpMRI in assessing the T stage and risk category was moderate (k = 0.53 and 0.56, respectively). mpMRI changed the T stage and risk category in 21.9% (95%C.I. 13.4–33-4) and 20.5% (95%C.I. 12.3–31.9), respectively, prevalently downstaging PCa compared to RE. Sensitivity and specificity for ≥T3 stage in the mpMRI validation group were 81.8% (95%C.I. 65.1–91.9) and 88.5% (72.8–96.1). Conclusion: RE and mpMRI show moderate agreement only in assessing the T-stage of PCa, translating into an mpMRI-induced change in risk assessment in about one fifth of patients. As supported by high sensitivity/specificity for ≥T3 stage in the validation group, the discrepancy we found is in favour of mpMRI as a tool to stage PCa before ERBT.

  16. Can multiparametric MRI replace Roach equations in staging prostate cancer before external beam radiation therapy?

    Energy Technology Data Exchange (ETDEWEB)

    Girometti, Rossano, E-mail: rgirometti@sirm.org [Institute of Diagnostic Radiology, Department of Medical and Biological Sciences, University of Udine, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia − via Colugna, 50–33100, Udine (Italy); Signor, Marco Andrea, E-mail: marco.signor@asuiud.sanita.fvg.it [Department of Oncological Radiation Therapy, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia, Piazzale S. M. della Misericordia, 15–33100, Udine (Italy); Pancot, Martina, E-mail: martypancot@libero.it [Institute of Diagnostic Radiology, Department of Medical and Biological Sciences, University of Udine, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia − via Colugna, 50–33100, Udine (Italy); Cereser, Lorenzo, E-mail: lcereser@sirm.org [Institute of Diagnostic Radiology, Department of Medical and Biological Sciences, University of Udine, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia − via Colugna, 50–33100, Udine (Italy); Zuiani, Chiara, E-mail: chiara.zuiani@uniud.it [Institute of Diagnostic Radiology, Department of Medical and Biological Sciences, University of Udine, Azienda Ospedaliero-Universitaria Santa Maria della Misericordia − via Colugna, 50–33100, Udine (Italy)

    2016-12-15

    Purpose: To investigate the agreement between Roach equations (RE) and multiparametric magnetic resonance imaging (mpMRI) in assessing the T-stage of prostate cancer (PCa). Materials and methods: Seventy-three patients with biopsy-proven PCa and previous RE assessment prospectively underwent mpMRI on a 3.0T magnet before external beam radiation therapy (EBRT). Using Cohen’s kappa statistic, we assessed the agreement between RE and mpMRI in defining the T-stage (≥T3 vs.T ≤ 2) and risk category according to the National comprehensive cancer network criteria (≤intermediate vs. ≥high). We also calculated sensitivity and specificity for ≥T3 stage in an additional group of thirty-seven patients with post-prostatectomy histological examination (mpMRI validation group). Results: The agreement between RE and mpMRI in assessing the T stage and risk category was moderate (k = 0.53 and 0.56, respectively). mpMRI changed the T stage and risk category in 21.9% (95%C.I. 13.4–33-4) and 20.5% (95%C.I. 12.3–31.9), respectively, prevalently downstaging PCa compared to RE. Sensitivity and specificity for ≥T3 stage in the mpMRI validation group were 81.8% (95%C.I. 65.1–91.9) and 88.5% (72.8–96.1). Conclusion: RE and mpMRI show moderate agreement only in assessing the T-stage of PCa, translating into an mpMRI-induced change in risk assessment in about one fifth of patients. As supported by high sensitivity/specificity for ≥T3 stage in the validation group, the discrepancy we found is in favour of mpMRI as a tool to stage PCa before ERBT.

  17. T2-weighted endorectal magnetic resonance imaging of prostate cancer after external beam radiation therapy

    International Nuclear Information System (INIS)

    Westphalen, Antonio C.; Kurhanewicz, John; Cunha, Rui M.G.; Hsu, I-Chow; Kornak, John; Zhao, Shoujun; Coakley, Fergus V.

    2009-01-01

    Purpose: To retrospectively determine the accuracy of T2-weighted endorectal MR imaging in the detection of prostate cancer after external beam radiation therapy and to investigate the relationship between imaging accuracy and time since therapy. Materials and Methods: Institutional review board approval was obtained and the study was HIPPA compliant. We identified 59 patients who underwent 1.5 Tesla endorectal MR imaging of the prostate between 1999 and 2006 after definitive external beam radiation therapy for biopsy-proven prostate cancer. Two readers recorded the presence or absence of tumor on T2-weighted images. Logistic regression and Fisher's exact tests for 2x2 tables were used to determine the accuracy of imaging and investigate if accuracy differed between those imaged within 3 years of therapy (n = 25) and those imaged more than 3 years after therapy (n = 34). Transrectal biopsy was used as the standard of reference for the presence or absence of recurrent cancer. Results: Thirty-four of 59 patients (58%) had recurrent prostate cancer detected on biopsy. The overall accuracy of T2-weighted MR imaging in the detection cancer after external beam radiation therapy was 63% (37/59) for reader 1 and 71% for reader 2 (42/59). For both readers, logistic regression showed no difference in accuracy between those imaged within 3 years of therapy and those imaged more than 3 years after therapy (p = 0.86 for reader 1 and 0.44 for reader 2). Conclusion: T2-weighted endorectal MR imaging has low accuracy in the detection of prostate cancer after external beam radiation therapy, irrespective of the time since therapy. (author)

  18. Eurados trial performance test for personal dosemeters for external beta radiation

    DEFF Research Database (Denmark)

    Christensen, P.; Bordy, J.M.; Ambrosi, P.

    2001-01-01

    On the initiative of the European Dosimetry Group (EURADOS) action group 'Harmonisation and Dosimetric Quality Assurance in Individual Monitoring for External Radiation' a trial performance test for whole-body and extremity personal dosemeters broadly representative of those in use in the EU...... the results obtained from the exercise. In particular, based on the replies to a questionnaire issued to each participant, the results are analysed in relation to important design characteristics of the dosemeters taking part in the test....

  19. Dose-rate conversion factors for external exposure to photon and electron radiation from radionuclides occurring in routine releases from nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1980-01-01

    Dose-rate conversion factors for external exposure to photon and electron radiation are calculated for 240 radionuclides of potential importance in routine releases from nuclear fuel cycle facilities. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each exposure mode, dose-rate conversion factors for photons and electrons are calculated for tissue-equivalent material at the body surface of an exposed individual. Dose-rate conversion factors for photons only are calculated for 22 body organs. (author)

  20. Analysis of the mortality among Cogema workers monitored for external radiation exposure

    International Nuclear Information System (INIS)

    Metz-Flamant, C.; Hitz, M.; Samson, E.; Rogel, A.; Telle-Lamberton, M.; Tirmarche, M.; Caer, S.; Quesne, B.

    2006-01-01

    The present study follows 9287 Cogema workers exposed to low level of ionizing radiation from the beginning of employment to the end of 1994. This paper presents analyses of the mortality of Cogema workers monitored for external radiation exposure and the relation between their mortality and their cumulative external radiation dose. Workers were followed up for an average of 13 years. The percentage of subjects lost to follow up was less than 1%. during the follow-up period, 441 deaths occurred. The mean cumulative dose among the whole cohort was 19.4 mSv. As expected, the mortality of the cohort was lower than that of the French national population. The healthy worker effect is often observed in other nuclear workers studies. Part of the healthy worker effect is explained by a proportion of unemployed persons in general population, with a higher mortality rate. All causes S.M.R. increased with calendar period and duration of employment. this increase was not significant for all cancers S.M.R. by duration of employment. This could illustrate the decrease of the initial selection at employment with time. A significant increase in risk was observed for all cancers excluding leukemia mortality with increase of radiation dose in the 15-country study. Significant excess of leukemia by cumulative radiation exposure was observed in the 3-country study and was borderline significant in the 15-country study and in the UK National register for radiation workers study. A positive trend, not statistically significant, by level of external doses was observed in our study for all cancers and leukemia excluding chronic lymphatic leukemia mortality, but the analyses lack of statistical power. A significant trend was observed only for non-Hodgkin lymphoma death, but considering the large number of statistic tests computed, this result must be carefully interpreted. A borderline significant trend was observed for lung cancer death, a significant increase risk of lung cancer death

  1. Treatment of Head and Neck Paragangliomas With External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Dupin, Charles, E-mail: c.dupin@bordeaux.unicancer.fr [Department of Radiotherapy, Comprehensive Cancer Center, Institut Bergonié, Bordeaux (France); Lang, Philippe [Department of Radiotherapy, Pitié Salpétrière, Paris (France); Dessard-Diana, Bernadette [Department of Radiotherapy, Hopital Européen Georges Pompidou, Paris (France); Simon, Jean-Marc; Cuenca, Xavier; Mazeron, Jean-Jacques; Feuvret, Loïc [Department of Radiotherapy, Pitié Salpétrière, Paris (France)

    2014-06-01

    Purpose: To retrospectively assess the outcomes of radiation therapy in patients with head and neck paragangliomas. Methods and Materials: From 1990 to 2009, 66 patients with 81 head and neck paragangliomas were treated by conventional external beam radiation therapy in 25 fractions at a median dose of 45 Gy (range, 41.4-68 Gy). One case was malignant. The median gross target volume and planning target volume were 30 cm{sup 3} (range, 0.9-243 cm{sup 3}) and 116 cm{sup 3} (range, 24-731 cm{sup 3}), respectively. Median age was 57.4 years (range, 15-84 years). Eleven patients had multicentric lesions, and 8 had family histories of paraganglioma. Paragangliomas were located in the temporal bone, the carotid body, and the glomus vagal in 51, 18, and 10 patients, respectively. Forty-six patients had exclusive radiation therapy, and 20 had salvage radiation therapy. The median follow-up was 4.1 years (range, 0.1-21.2 years). Results: One patient had a recurrence of temporal bone paraganglioma 8 years after treatment. The actuarial local control rates were 100% at 5 years and 98.7% at 10 years. Patients with multifocal tumors and family histories were significantly younger (42 years vs 58 years [P=.002] and 37 years vs 58 years [P=.0003], respectively). The association between family predisposition and multifocality was significant (P<.001). Two patients had cause-specific death within the 6 months after irradiation. During radiation therapy, 9 patients required hospitalization for weight loss, nausea, mucositis, or ophthalmic zoster. Two late vascular complications occurred (middle cerebral artery and carotid stenosis), and 2 late radiation-related meningiomas appeared 15 and 18 years after treatment. Conclusion: Conventional external beam radiation therapy is an effective and safe treatment option that achieves excellent local control; it should be considered as a first-line treatment of choice for head and neck paragangliomas.

  2. Treatment of Head and Neck Paragangliomas With External Beam Radiation Therapy

    International Nuclear Information System (INIS)

    Dupin, Charles; Lang, Philippe; Dessard-Diana, Bernadette; Simon, Jean-Marc; Cuenca, Xavier; Mazeron, Jean-Jacques; Feuvret, Loïc

    2014-01-01

    Purpose: To retrospectively assess the outcomes of radiation therapy in patients with head and neck paragangliomas. Methods and Materials: From 1990 to 2009, 66 patients with 81 head and neck paragangliomas were treated by conventional external beam radiation therapy in 25 fractions at a median dose of 45 Gy (range, 41.4-68 Gy). One case was malignant. The median gross target volume and planning target volume were 30 cm 3 (range, 0.9-243 cm 3 ) and 116 cm 3 (range, 24-731 cm 3 ), respectively. Median age was 57.4 years (range, 15-84 years). Eleven patients had multicentric lesions, and 8 had family histories of paraganglioma. Paragangliomas were located in the temporal bone, the carotid body, and the glomus vagal in 51, 18, and 10 patients, respectively. Forty-six patients had exclusive radiation therapy, and 20 had salvage radiation therapy. The median follow-up was 4.1 years (range, 0.1-21.2 years). Results: One patient had a recurrence of temporal bone paraganglioma 8 years after treatment. The actuarial local control rates were 100% at 5 years and 98.7% at 10 years. Patients with multifocal tumors and family histories were significantly younger (42 years vs 58 years [P=.002] and 37 years vs 58 years [P=.0003], respectively). The association between family predisposition and multifocality was significant (P<.001). Two patients had cause-specific death within the 6 months after irradiation. During radiation therapy, 9 patients required hospitalization for weight loss, nausea, mucositis, or ophthalmic zoster. Two late vascular complications occurred (middle cerebral artery and carotid stenosis), and 2 late radiation-related meningiomas appeared 15 and 18 years after treatment. Conclusion: Conventional external beam radiation therapy is an effective and safe treatment option that achieves excellent local control; it should be considered as a first-line treatment of choice for head and neck paragangliomas

  3. Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning

    International Nuclear Information System (INIS)

    Paulson, Eric S.; Erickson, Beth; Schultz, Chris; Allen Li, X.

    2015-01-01

    Purpose: The use of magnetic resonance imaging (MRI) in radiation oncology is expanding rapidly, and more clinics are integrating MRI into their radiation therapy workflows. However, radiation therapy presents a new set of challenges and places additional constraints on MRI compared to diagnostic radiology that, if not properly addressed, can undermine the advantages MRI offers for radiation treatment planning (RTP). The authors introduce here strategies to manage several challenges of using MRI for virtual simulation in external beam RTP. Methods: A total of 810 clinical MRI simulation exams were performed using a dedicated MRI scanner for external beam RTP of brain, breast, cervix, head and neck, liver, pancreas, prostate, and sarcoma cancers. Patients were imaged in treatment position using MRI-optimal immobilization devices. Radiofrequency (RF) coil configurations and scan protocols were optimized based on RTP constraints. Off-resonance and gradient nonlinearity-induced geometric distortions were minimized or corrected prior to using images for RTP. A multidisciplinary MRI simulation guide, along with window width and level presets, was created to standardize use of MR images during RTP. A quality assurance program was implemented to maintain accuracy and repeatability of MRI simulation exams. Results: The combination of a large bore scanner, high field strength, and circumferentially wrapped, flexible phased array RF receive coils permitted acquisition of thin slice images with high contrast-to-noise ratio (CNR) and image intensity uniformity, while simultaneously accommodating patient setup and immobilization devices. Postprocessing corrections and alternative acquisition methods were required to reduce or correct off-resonance and gradient nonlinearity induced geometric distortions. Conclusions: The methodology described herein contains practical strategies the authors have implemented through lessons learned performing clinical MRI simulation exams. In

  4. Comprehensive MRI simulation methodology using a dedicated MRI scanner in radiation oncology for external beam radiation treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Paulson, Eric S., E-mail: epaulson@mcw.edu [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 and Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 (United States); Erickson, Beth; Schultz, Chris; Allen Li, X. [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226 (United States)

    2015-01-15

    Purpose: The use of magnetic resonance imaging (MRI) in radiation oncology is expanding rapidly, and more clinics are integrating MRI into their radiation therapy workflows. However, radiation therapy presents a new set of challenges and places additional constraints on MRI compared to diagnostic radiology that, if not properly addressed, can undermine the advantages MRI offers for radiation treatment planning (RTP). The authors introduce here strategies to manage several challenges of using MRI for virtual simulation in external beam RTP. Methods: A total of 810 clinical MRI simulation exams were performed using a dedicated MRI scanner for external beam RTP of brain, breast, cervix, head and neck, liver, pancreas, prostate, and sarcoma cancers. Patients were imaged in treatment position using MRI-optimal immobilization devices. Radiofrequency (RF) coil configurations and scan protocols were optimized based on RTP constraints. Off-resonance and gradient nonlinearity-induced geometric distortions were minimized or corrected prior to using images for RTP. A multidisciplinary MRI simulation guide, along with window width and level presets, was created to standardize use of MR images during RTP. A quality assurance program was implemented to maintain accuracy and repeatability of MRI simulation exams. Results: The combination of a large bore scanner, high field strength, and circumferentially wrapped, flexible phased array RF receive coils permitted acquisition of thin slice images with high contrast-to-noise ratio (CNR) and image intensity uniformity, while simultaneously accommodating patient setup and immobilization devices. Postprocessing corrections and alternative acquisition methods were required to reduce or correct off-resonance and gradient nonlinearity induced geometric distortions. Conclusions: The methodology described herein contains practical strategies the authors have implemented through lessons learned performing clinical MRI simulation exams. In

  5. Calculations of External Irradiation from Radioactive Plume in the Early Stage of Nuclear Accident

    Czech Academy of Sciences Publication Activity Database

    Pecha, Petr; Hofman, Radek

    Vol. 50, č. 1-4 (2012), s. 420-430 ISSN 1741-5101 R&D Projects: GA MV(CZ) VG20102013018 Institutional support: RVO:67985556 Keywords : radioactivity release * photon fluence * external irradiation * data assimilation Subject RIV: AQ - Safety, Health Protection, Human - Machine http://library.utia.cas.cz/separaty/2012/AS/pecha-0385225.pdf

  6. Radiation damage calculations for the APT materials test program

    International Nuclear Information System (INIS)

    Corzine, R.K.; Wechsler, M.S.; Dudziak, D.J.; Ferguson, P.D.; James, M.R.

    1999-01-01

    A materials irradiation was performed at the Los Alamos Neutron Science Center (LANSCE) in the fall of 1996 and spring of 1997 in support of the Accelerator Production of Tritium (APT) program. Testing of the irradiated materials is underway. In the proposed APT design, materials in the target and blanket are to be exposed to protons and neutrons over a wide range of energies. The irradiation and testing program was undertaken to enlarge the very limited direct knowledge presently available of the effects of medium-energy protons (∼1 GeV) on the properties of engineering materials. APT candidate materials were placed in or near the LANSCE accelerator 800-MeV, 1-mA proton beam and received roughly the same proton current density in the center of the beam as would be the case for the APT facility. As a result, the proton fluences achieved in the irradiation were expected to approach the APT prototypic full-power-year values. To predict accurately the performance of materials in APT, radiation damage parameters for the materials experiment must be determined. By modeling the experiment, calculations for atomic displacement, helium and hydrogen cross sections and for proton and neutron fluences were done for representative samples in the 17A, 18A, and 18C areas. The LAHET code system (LCS) was used to model the irradiation program, LAHET 2.82 within LCS transports protons > 1 MeV, and neutrons >20 MeV. A modified version of MCNP for use in LCS, HMCNP 4A, was employed to tally neutrons of energies <20 MeV

  7. Study of External Radiation Expose Dose on Hands of Nuclear Medicine Workers

    International Nuclear Information System (INIS)

    Park, Jun Chul; Pyo, Sung Jae

    2012-01-01

    The aims of this study are to assess external radiation exposed doses of body and hands of nuclear medicine workers who handle radiation sources, and to measure radiation exposed doses of the hands induced by a whole body bone scan with high frequency and handling a radioactive sources like 99m Tc-HDP and 18 F-FDG in the PET/CT examination. Skillful workers, who directly dispense and inject from radiation sources, were asked to wear a TLD on the chest and ring finger. Then, radiation exposed dose and duration exposed from daily radiation sources for each section were measured by using a pocket dosimeter for the accumulated external doses and the absorbed dose to the hands. In the survey of four medical institutions in Incheon Metropolitan City, only one of four institutions has a radiation dosimeter for local area like hands. Most of institutions uses radiation shielding devices for the purpose of protecting the body trunk, not local area. Even some institutions were revealed not to use such a shielding device. The exposed doses on the hands of nuclear medicine workers who directly handles radioactive sources were approximately twice as much as those on the body. The radiation exposure level for each section of the whole body bone scan with high frequency and that of the PET/CT examination showed that radiation doses were revealed in decreasing order of synthesis of radioactive medicine and installation to a dispensing container, dispensing, administering and transferring. Furthermore, there were statistically significant differences of radiation exposure doses of the hands before and after wearing a syringe shielder in administration of a radioactive sources. In this study, although it did not reach the permissible effective dose for nuclear medicine, the occupational workers were exposed by relatively higher dose level than the non-occupational workers. Therefore, the workers, who closely exposed to radioactive sources should be in compliance with safety

  8. Measurement of the natural radiation environment and its dependence on various parameters in Austria and assessment of the natural external and internal radiation dose of various population groups

    International Nuclear Information System (INIS)

    Pohl, E.

    1978-06-01

    The natural mean values of natural radionuclides in the air and external gamma radiation were determined from measurements carried out in various parts of Austria and the mean values were used as a basis for the determination of body and organ doses. Moreover frequency distributions of several specific organ doses within various population groups were investigated. Measurements of natural air activity were carried out indoors and outdoors as well as gamma radiation at the following sites - Salzburg Town, Badgastein, Gastein Valley and Mallnitz and several other places at a line crossing the Alps from South to North (Corinthia, Schwarzach, Forstau, Hallein, Kuchl, Grodig and Voggenberg - Bergheim) and in 15 different mines in the Counties of Salzburg and Upper Austria. The methods of calculation of the radiation burden due to inhalation is published in the Proceedings of the Symposium on Biological and Environmental Effects of Low Level Radiation, IAEA, Chicago 1976, Vol. II pages 305-315. It can be concluded from the work that great local differences of some components occur even within relatively small areas. The radioactivity in the air shows great temporal differences at one and the same site. In addition radiation doses had to be calculated separately for various organs and tissues due to the inhomogeneous distribution of doses within the body. Also the estimation had to be made for a variety of individuals depending on sex, age, weight and various physiological states of activity. The highest doses to tissues from inhalation of natural radioactivity are the basal cells of the sigmental epithelium and subsigmental bronchi 4th - 9th generation in the lung model of Weibel. 46% of the population investigated received more than 0.5 rem per year, 25% more than 1.5 rem per year and 1.3% more than 3 rem per year. The different air activities in the living and working rooms are due to differences in the building materials and in the construction of houses

  9. Life cycle assessment of renewables: present issues, future outlook and implications for the calculation of external costs

    International Nuclear Information System (INIS)

    Frankl, P.

    2002-01-01

    In principle, Life Cycle Assessment (LCA) is certainly appropriate for estimating external costs of renewables, since major environmental impacts of the latter are generated in phases of the life cycle other than use. In practice however, several issues still remain. They are related to the availability and quality of Life Cycle Inventory (LCI) data, to the frit technological development of renewable energy technologies (RET), to the existence of many different applications of the latter and to a strong dependency on local conditions. Moreover, a 'static' picture of present technologies is not enough for policy indications. Therefore some kind of dynamic LCA is needed. These LCA issues are reflected in the calculation of external costs. First, the paper discusses these issues on the examples of two main technologies, namely photovoltaic (PV) and wind. Second, it discusses the results of ExternE for these two specific technologies and gives an outlook for the future. Future needs for a better use of LCA as a support tool for the calcination of external costs are identified. Finally, a new research project funded by the European Commission focused on LCI of renewables is briefly introduced and presented. (author)

  10. Offsite radiation doses from Hanford Operations for the years 1983 through 1987: A comparison of results calculated by two methods

    International Nuclear Information System (INIS)

    Soldat, J.K.

    1989-10-01

    This report compares the results of the calculation of potential radiation doses to the public by two different environmental dosimetric systems for the years 1983 through 1987. Both systems project the environmental movement of radionuclides released with effluents from Hanford operations; their concentrations in air, water, and foods; the intake of radionuclides by ingestion and inhalation; and, finally, the potential radiation doses from radionuclides deposited in the body and from external sources. The first system, in use for the past decade at Hanford, calculates radiation doses in terms of 50-year cumulative dose equivalents to body organs and to the whole body, based on the methodology defined in ICRP Publication 2. This system uses a suite of three computer codes: PABLM, DACRIN, and KRONIC. In the new system, 50-year committed doses are calculated in accordance with the recommendations of the ICRP Publications 26 and 30, which were adopted by the US Department of Energy (DOE) in 1985. This new system calculates dose equivalent (DE) to individual organs and effective dose equivalent (EDE). The EDE is a risk-weighted DE that is designed to be an indicator of the potential health effects arising from the radiation dose. 16 refs., 1 fig., 38 tabs

  11. Mortality among workers exposed to external ionizing radiation at a nuclear facility in Ohio

    International Nuclear Information System (INIS)

    Wiggs, L.D.; Cox-DeVore, C.A.; Wilkinson, G.S.; Reyes, M.

    1991-01-01

    In a cohort mortality study of white men employed by the Mound Facility (1947 through 1979), observed deaths did not exceed those expected based on US death rates for the overall cohort or for the subcohort monitored for external ionizing radiation. Among the radiation-monitored subcohort, mortality for workers with cumulative radiation doses of at least 10 mSv was not significantly increased when compared with mortality for coworkers with cumulative doses of less than 10 mSv. A significant dose-response based on a Mantel-Haenszel test of trend was observed for all leukemias. However, when a death from chronic lymphatic leukemia, a type of leukemia generally not regarded as radiogenic, was removed from the analyses, the strength of the dose-response was reduced

  12. External review systems for radiation oncology facilities - clinical audit versus other review systems

    International Nuclear Information System (INIS)

    Bogusz-Czerniewicz, M.

    2009-01-01

    Background: Between 1996 and 1999 project team of ExPeRT, catalogued four external review systems of health care facilities in the European Union and countries associated with EU. Aim: The aim of this paper is a/ to identify and compare currently existing external review systems for radiation oncology facilities and b/ to distinguish main differences between clinical audit and other external evaluation models and c/ to identify where those models are currently used in European Union member states. Materials and Methods: Based on the literature review and the survey conducted between January and April 2007 among representatives of 67 national societies (for diagnostic radiology, radiotherapy and nuclear medicine) in European Union member states, the analysis of existing external review systems in radiation oncology was performed. Relevant information about purpose, scope and methodology of evaluation process for those systems were surveyed. Results: The response to the questionnaire was 72%. Only a few countries did not supply any reply in spite of repeated enquiries to several recipients. Six main categories of systems aiming at measuring the quality of service management and delivery were identified: professional peer review -based schemes, hospital accreditation, accreditation in terms of ISO standards, award seeking, certification by International Standards Organization, and clinical audit. Conclusions: Though the methodology and terminology of the five main external review systems differ, a constant movement towards collaboration and convergence of those models has been observed. Due to the social, political, and economical aspects of each European country, the different audit systems have been implemented either on voluntary or mandatory basis. (author)

  13. Proposal on the accelerator driven molten-salt reactor (ATW concept) benchmark calculations. (STAGE 1 - without an external neutron source)

    International Nuclear Information System (INIS)

    Svarny, J.; Mikolas, P.

    1999-01-01

    The first stage of ATW neutronic benchmark (without an external source), based on the simple modelling of two component concept is presented. The simple model of two component concept of the ATW (graphite + molten salt system) was found. The main purpose of this benchmark is not only to provide the basic characteristics of given ADS but also to test codes in calculations of the rate of transmutation waste and to evaluate basic kinetics parameters and reactivity effects. (author)

  14. Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy.

    Science.gov (United States)

    Eftekhari, Mohammad; Anbiaei, Robabeh; Zamani, Hanie; Fallahi, Babak; Beiki, Davood; Ameri, Ahmad; Emami-Ardekani, Alireza; Fard-Esfahani, Armaghan; Gholamrezanezhad, Ali; Seid Ratki, Kazem Razavi; Roknabadi, Alireza Momen

    2015-01-01

    Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right-sided cancer. To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring) were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT) to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions) over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol) was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed) and 36 patients with right-sided cancer (controls)] were enrolled. Dose-volume histogram (DVH) [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46). In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03) and anterolateral (17.1% versus 2.8%, P=0.049) walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS) of>3 was observed in twelve cases (34.3%), while in five of the controls (13.9%),(Odds ratio=1.3). There was no significant difference between the groups regarding left ventricular ejection fraction. The risk of radiation induced myocardial perfusion abnormality in patients treated with CRT on the

  15. Radiation-induced myocardial perfusion abnormalities in breast cancer patients following external beam radiation therapy

    Directory of Open Access Journals (Sweden)

    Mohammad Eftekhari

    2015-01-01

    Full Text Available Objective(s: Radiation therapy for breast cancer can induce myocardial capillary injury and increase cardiovascular morbidity and mortality. A prospective cohort was conducted to study the prevalence of myocardial perfusion abnormalities following radiation therapy of left-sided breast cancer patients as compared to those with right–sided cancer. Methods: To minimize potential confounding factors, only those patients with low 10-year risk of coronary artery disease (based on Framingham risk scoring were included. All patients were initially treated by modified radical mastectomy and then were managed by postoperative 3D Conformal Radiation Therapy (CRT to the surgical bed with an additional 1-cm margin, delivered by 46-50 Gy (in 2 Gy daily fractions over a 5-week course. The same dose-adjusted chemotherapy regimen (including anthracyclines, cyclophosphamide and taxol was given to all patients. Six months after radiation therapy, all patients underwent cardiac SPECT for the evaluation of myocardial perfusion. Results: A total of 71 patients with a mean age of 45.3±7.2 years [35 patients with leftsided breast cancer (exposed and 36 patients with right-sided cancer (controls] were enrolled. Dose-volume histogram (DVH [showing the percentage of the heart exposed to >50% of radiation] was significantly higher in patients with left-sided breast cancer. Visual interpretation detected perfusion abnormalities in 42.9% of cases and 16.7% of controls (P=0.02, Odds ratio=1.46. In semiquantitative segmental analysis, only apical (28.6% versus 8.3%, P=0.03 and anterolateral (17.1% versus 2.8%, P=0.049 walls showed significantly reduced myocardial perfusion in the exposed group. Summed Stress Score (SSS of>3 was observed in twelve cases (34.3%, while in five of the controls (13.9%,(Odds ratio=1.3. There was no significant difference between the groups regarding left ventricular ejection fraction. Conclusion: The risk of radiation induced myocardial

  16. New physical model calculates airline crews' radiation exposure

    Science.gov (United States)

    Schultz, Colin

    2013-12-01

    Airline pilots and crews, who spend hundreds of hours each year flying at high altitude, are exposed to increased doses of radiation from galactic cosmic rays and solar energy particles, enough that airline crew members are actually considered radiation workers by the International Commission on Radiological Protection.

  17. The use of externality estimates in the calculation of adders by state PUC regulators

    International Nuclear Information System (INIS)

    Burtraw, D.; Palmer, K.; Krupnick, A.

    1994-01-01

    The primary focus of the U. S.-EC study is the development and illustration of methodologies for the estimation of marginal damages and associated externalities that result from the addition of electricity generating capacity in a specific reference environment. This paper describes how this information can be used to guide resource planning by electric utilities and State public utility commissions (PUCs). First, we discuss the 'second-best' policy environment in which PUCs must operate. We then discuss the use of 'adders' which are a policy tool that many PUCs are currently considering. Then, we introduce and estimate a formal model to calibrate these adders, based on estimates of externalities in order to promote economic efficiency in resource planning and investment decisions

  18. The use of externality estimates in the calculation of adders by state PUC regulators

    Energy Technology Data Exchange (ETDEWEB)

    Burtraw, D; Palmer, K; Krupnick, A

    1994-07-01

    The primary focus of the U. S.-EC study is the development and illustration of methodologies for the estimation of marginal damages and associated externalities that result from the addition of electricity generating capacity in a specific reference environment. This paper describes how this information can be used to guide resource planning by electric utilities and State public utility commissions (PUCs). First, we discuss the 'second-best' policy environment in which PUCs must operate. We then discuss the use of 'adders' which are a policy tool that many PUCs are currently considering. Then, we introduce and estimate a formal model to calibrate these adders, based on estimates of externalities in order to promote economic efficiency in resource planning and investment decisions.

  19. Clinical Implications of TiGRT Algorithm for External Audit in Radiation Oncology

    OpenAIRE

    Daryoush Shahbazi-Gahrouei; Mohsen Saeb; Shahram Monadi; Iraj Jabbari

    2017-01-01

    Background: Performing audits play an important role in quality assurance program in radiation oncology. Among different algorithms, TiGRT is one of the common application software for dose calculation. This study aimed to clinical implications of TiGRT algorithm to measure dose and compared to calculated dose delivered to the patients for a variety of cases, with and without the presence of inhomogeneities and beam modifiers. Materials and Methods: Nonhomogeneous phantom as quality dose veri...

  20. Early radiation changes of normal dog brain following internal and external brain irradiation: A preliminary report

    International Nuclear Information System (INIS)

    Chin, H.; Maruyama, Y.; Markesbery, W.; Goldstein, S.; Wang, P.; Tibbs, P.; Young, B.; Feola, J.; Beach, L.

    1984-01-01

    To examine radiation-induced changes in the normal brain, internal or external radiation was given to normal dog brain. Seven medium-sized dogs were used in this study. Two dogs were controls and an ice-pick (plastic implant applicator) was placed in the right frontal lobe for about 5 hours but no irradiation. Two dogs underwent Cs-137 brain implantation for 4 and 5 hours, respectively using an ice-pick technique. Two dogs were given internal neutron irradiation using the same technique of intracerebral ice-pick brachytherapy. One dog received an external photon irradiation using 6-Mev Linear Accelerator. Postmortem microscopic examination was made to study the early cerebral changes to irradiation in three dogs: one control with no irradiation; one received intracerebral Cesium implantation; and one external photon irradiation. Vascular change was the most prominent microscopic finding. There were hemorrhage, endothelial proliferation and fibrinoid changes of small vessel wall. Most of the changes were localized in the white matter and the cortex remained intact. Details (CT, NMR and histological studies) are discussed

  1. Changes of medullary hemopoiesis produced by chronic exposure to tritium oxide and external γ-radiation

    International Nuclear Information System (INIS)

    Murzina, L.D.; Muksinova, K.N.

    1982-01-01

    A comparative study of a chronic effect of tritium oxide ( 3 HOH) and external γ-radiation by 137 Cs on medullary hemopoiesis was conducted in experiments on Wistar rats. 3 HOH was administered for 3mos., 37x10 4 Bk per lg per of body mass daily (the absorbed dose 10.8 Gy), external irradiation was given in correlated values of dose rates and integral doses. Bone marrow depopulation was 1.9 times as deeper in rats exposed to 3 HOH as compared to that in irradiated rats. This difference is caused by early and stable inhibition of erythropoiesis with the administration of the radionuclide. The integral index showing the injuring effect of tritium on erythropoiesis was 4 times as high as compared to that of external γ-irradiation by 137 Cs. The time course of value of the proliferative pool of bone marrow granulocytes with the exposure to 2 types of radiation was monotypic. Differences in maturing and functioning granulocytic pools were marked in early time of the experiment

  2. Relationships between the operator's radiation protection expert and the radiation protection expert belonging to an external company

    International Nuclear Information System (INIS)

    Gravelotte, D.

    2008-01-01

    The radiation protection expert (PCR in French for Personne Competente en Radioprotection) is a central actor in the organization of radioprotection. Such a person is required within radioprotection departments of basic nuclear installations as well in external companies intervening in these installations. After having recalled that relationship between these both experts is promoted by the legal framework, the author describes how this relationship is planned in the Paluel French nuclear power station. He indicates the type of data and information concerning the power station activities which are exchanged between them. He also presents the actions which have been defined to promote this relationship

  3. Calculation of the Coherent Synchrotron Radiation Impedance from a Wiggler

    International Nuclear Information System (INIS)

    Wu, Juhao

    2003-01-01

    Most studies of Coherent Synchrotron Radiation (CSR) have only considered the radiation from independent dipole magnets. However, in the damping rings of future linear colliders, a large fraction of the radiation power will be emitted in damping wigglers. In this paper, the longitudinal wakefield and impedance due to CSR in a wiggler are derived in the limit of a large wiggler parameter K. After an appropriate scaling, the results can be expressed in terms of universal functions, which are independent of K. Analytical asymptotic results are obtained for the wakefield in the limit of large and small distances, and for the impedance in the limit of small and high frequencies

  4. Calculations of radiation levels during reactor operations for safeguard inspections

    International Nuclear Information System (INIS)

    Sobhy, M.

    1996-01-01

    When an internal core spent fuel storage is used in the shield tank to accommodate a large number of spent fuel baskets, physical calculations are performed to determine the number of these spent fuel elements which can be accommodated and still maintain the gamma activity outside under the permissible limit. The corresponding reactor power level is determined. The radioactivity calculations are performed for this internal storage at different axial levels to avoid the criticality of the reactor core. Transport theory is used in calculations based on collision probability for multi group cell calculations. Diffusion theory is used in three dimensions in the core calculations. The nuclear fuel history is traced and radioactive decay is calculated, since reactor fission products are very sensitive to power level. The radioactivity is calculated with a developed formula based on fuel basket loading integrity. (author)

  5. Evaluation of Cost and Effectiveness of Decontamination Scenarios on External Radiation Exposure in Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Yasutaka, T.; Naito, W. [National Institute of Advanced Industrial Science and Technology (Japan)

    2014-07-01

    Despite the enormous cost associated with radiation decontamination, almost no quantitative assessment has been performed on the relationship between the potential reduction in long-term radiation exposure and the costs of the various decontamination strategies considered for the decontamination areas in Fukushima. In order to establish effective and pragmatic decontamination strategies for use in the radiation contaminated areas in Fukushima, a holistic approach for assessing decontamination strategies, their costs, and long-term external radiation doses is needed. The objective of the present study is to evaluate the cost and effectiveness of decontamination scenarios in the decontamination areas in Fukushima in regard to external radiation exposure. The choice of decontamination strategies in the decontamination areas should be based on a comprehensive analysis of multiple attributes such as radiological, economic, and socio-psychological attributes. The cost and effectiveness of the different decontamination strategies is not sole determinant of the decontamination strategies of the special decontamination area but is one of the most important attributes when making the policy decision. In the current study, we focus on radiological and economic attributes in determining decontamination strategies. A geographical information system (GIS) was used to relate the predicted external dose in the affected areas to the number of potential inhabitants and the land use in the areas. A comprehensive review of the costs of various decontamination methods was conducted as part of the analysis. The results indicate that aerial decontamination in the special decontamination areas in Fukushima would be effective for reducing the air dose rate to the target level in a short period of time in some but not all of the areas. In a standard scenario, the analysis of cost suggests that decontamination costs of decontamination in Fukushima was estimated to be up to approximately 5

  6. Review of personal monitoring techniques for the measurement of absorbed dose from external beta and low energy photon radiation

    DEFF Research Database (Denmark)

    Christensen, Poul

    1986-01-01

    The techniques available at present for personal monitoring of doses from external beta and low energy photon radiation are reviewed. The performance of currently used dosimetry systems is compared with that recommended internationally, and developments for improving the actual performance...

  7. Modeling for Dose Rate Calculation of the External Exposure to Gamma Emitters in Soil

    International Nuclear Information System (INIS)

    Allam, K. A.; El-Mongy, S. A.; El-Tahawy, M. S.; Mohsen, M. A.

    2004-01-01

    Based on the model proposed and developed in Ph.D thesis of the first author of this work, the dose rate conversion factors (absorbed dose rate in air per specific activity of soil in nGy.hr - 1 per Bq.kg - 1) are calculated 1 m above the ground for photon emitters of natural radionuclides uniformly distributed in the soil. This new and simple dose rate calculation software was used for calculation of the dose rate in air 1 m above the ground. Then the results were compared with those obtained by five different groups. Although the developed model is extremely simple, the obtained results of calculations, based on this model, show excellent agreement with those obtained by the above-mentioned models specially that one adopted by UNSCEAR. (authors)

  8. Calculation of radiation fields for Hanford tank riser modifications

    International Nuclear Information System (INIS)

    Schwarz, R.A.; Carter, L.L.; Hillesland, K.E.

    1994-10-01

    A visualization process has been created to animate the dose rates from radiation sources as the source and shielding configuration are modified. This process has been illustrated with the removal of a mixer pump from a Hanford Site waste tank

  9. Serum testosterone levels after external beam radiation for clinically localized prostate cancer

    International Nuclear Information System (INIS)

    Zagars, Gunar K.; Pollack, Alan

    1997-01-01

    Purpose: To determine whether serum total testosterone levels change after external beam radiation therapy for localized prostate cancer. Methods and Materials: Eighty-five men with clinically localized prostate cancer (T1-T3, N0/NX, M0) who underwent external beam radiation therapy without androgen ablation had pretreatment and 3-month posttreatment total serum testosterone levels determined by radioimmunoassay. Scattered doses to the testicles were measured with thermoluminescent dosimetry in 10 men. Results: Pretreatment serum testosterone levels ranged from 185 to 783 ng/dl, with a mean of 400 ng/dl and a median of 390 ng/dl. The coefficient of variation was 30%. Postradiation 3-month testosterone levels ranged from 163 ng/dl to 796 ng/dl, with mean and median values of 356 ng/dl and 327 ng/ml, respectively. The coefficient of variation was 34%. The 3-month value was significantly lower than the pretreatment value (Wilcoxon paired p = 0.0001). The mean absolute fall was 94 ng/dl and the mean percentage fall was 9%. Although the fall in testosterone level was statistically significant, the difference was very small quantitatively. In contrast, serum prostate-specific antigen levels fell dramatically by 3 months after radiation. Testicular scattered doses ranged from 1.84 to 2.42 Gy, with a mean of 2.07 Gy for a prostatic tumor dose of 68 Gy. Conclusions: Although significant, the fall in serum testosterone level after radiation for localized prostate cancer was small and likely of no pathophysiologic consequence. It is unlikely that scattered testicular radiation plays any significant role in the genesis of this change in testosterone level, which most likely occurs as a nonspecific stress response

  10. External radiation therapy of prostatic carcinoma and its relationship to hormonal therapy

    International Nuclear Information System (INIS)

    Takada, Chitose; Ito, Koushiro; Nishi, Junko; Yamamoto, Toshihiro; Hatanaka, Yoshimi; Baba, Yuji; Takahashi, Mutsumasa.

    1995-01-01

    From 1980 to 1990, a total of 54 patients with prostatic carcinoma were treated with external radiation therapy at the Kumamoto National Hospital. Ten patients were classified as Stage B, 22 as Stage C, and another 22 as Stage D according to the American Urological Association Clinical Staging System. The 5-year survival for all 54 patients was 30%. The 5-year disease-specific survival was 67% for Stage B, 47% for Stage C, and 26% for Stage D. The 5-year survival was 43% for patients in whom radiation therapy was initiated immediately after the first diagnosis or with less than one year of hormonal therapy, while it was 0% for patients in whom radiation therapy was initiated after more than one year of hormonal therapy (p=0.01). The cause of intercurrent death was acute myocardial infarction in four patients and acute cardiac failure in one. Four of these patients received hormonal therapy for more than one year. The incidence of radiation-induced proctitis was not severe. This study suggests that long-term hormonal therapy prior to radiation therapy worsens the prognosis of patients with prostatic carcinoma. (author)

  11. Thyroid Cancer after Childhood Exposure to External Radiation: An Updated Pooled Analysis of 12 Studies

    Science.gov (United States)

    Veiga, Lene H. S.; Holmberg, Erik; Anderson, Harald; Pottern, Linda; Sadetzki, Siegal; Adams, M. Jacob; Sakata, Ritsu; Schneider, Arthur B.; Inskip, Peter; Bhatti, Parveen; Johansson, Robert; Neta, Gila; Shore, Roy; de Vathaire, Florent; Damber, Lena; Kleinerman, Ruth; Hawkins, Michael M.; Tucker, Margaret; Lundell, Marie; Lubin, Jay H.

    2016-01-01

    Studies have causally linked external thyroid radiation exposure in childhood with thyroid cancer. In 1995, investigators conducted relative risk analyses of pooled data from seven epidemiologic studies. Doses were mostly 50 Gy. We pooled data from 12 studies of thyroid cancer patients who were exposed to radiation in childhood (ages <20 years), more than doubling the data, including 1,070 (927 exposed) thyroid cancers and 5.3 million (3.4 million exposed) person-years. Relative risks increased supralinearly through 2–4 Gy, leveled off between 10–30 Gy and declined thereafter, remaining significantly elevated above 50 Gy. There was a significant relative risk trend for doses <0.10 Gy (P < 0.01), with no departure from linearity (P = 0.36). We observed radiogenic effects for both papillary and nonpapillary tumors. Estimates of excess relative risk per Gy (ERR/Gy) were homogeneous by sex (P = 0.35) and number of radiation treatments (P = 0.84) and increased with decreasing age at the time of exposure. The ERR/Gy estimate was significant within ten years of radiation exposure, 2.76 (95% CI, 0.94–4.98), based on 42 exposed cases, and remained elevated 50 years and more after exposure. Finally, exposure to chemotherapy was significantly associated with thyroid cancer, with results supporting a nonsynergistic (additive) association with radiation. PMID:27128740

  12. Assessment of internal and external exposure to ionizing radiation in laboratories of nuclear medicine and radiotherapy

    International Nuclear Information System (INIS)

    Adamiak-Ziemba, J.; Doniec, J.; Kocznow, W.; Hawrynski, M.

    1985-01-01

    The investigations with determination of radioisotopes in urine led to detection of contamination with 99m Tc and radioactive iodine. The measurements and dosimetry of external radiation demonstrated that workers in laboratories of radioisotope diagnosis received a mean annual equivalent doses amounted less than 5% of the permissible dose for persons with occupational exposure. It was also established that external exposure was mainly responsible for this. The data about the levels of internal exposure in laboratories of nuclear medicine and radiotherapy demonstrated that introduction of a permanent central system of control of internal contamination of workers would be useless since the observation of the already accepted principles of radiological protection is sufficient for avoiding contamination. (author)

  13. PKI, Gamma Radiation Reactor Shielding Calculation by Point-Kernel Method

    International Nuclear Information System (INIS)

    Li Chunhuai; Zhang Liwu; Zhang Yuqin; Zhang Chuanxu; Niu Xihua

    1990-01-01

    1 - Description of program or function: This code calculates radiation shielding problem of gamma-ray in geometric space. 2 - Method of solution: PKI uses a point kernel integration technique, describes radiation shielding geometric space by using geometric space configuration method and coordinate conversion, and makes use of calculation result of reactor primary shielding and flow regularity in loop system for coolant

  14. Calculation of radiation losses in cylinder symmetric high pressure discharges by means of a digital computer

    International Nuclear Information System (INIS)

    Andriessen, F.J.; Boerman, W.; Holtz, I.F.E.M.

    1973-08-01

    Computer calculations have been made of radiative energy losses in a cylindrically symmetric high pressure discharge. The calculations show that the radiation losses which occur in discharges at pressures of a few atmospheres and central temperatures of about 20000degK when compared with the electrical energy supplied, are only of importance in the neighbourhood of the centre of discharge

  15. A solution algorithm for calculating photon radiation fields with the aid of the Monte Carlo method

    International Nuclear Information System (INIS)

    Zappe, D.

    1978-04-01

    The MCTEST program and its subroutines for the solution of the Boltzmann transport equation is presented. The program renders possible to calculate photon radiation fields of point or plane gamma sources. After changing two subroutines the calculation can also be carried out for the case of directed incidence of radiation on plane shields of iron or concrete. (author)

  16. BALTORO a general purpose code for coupling discrete ordinates and Monte-Carlo radiation transport calculations

    International Nuclear Information System (INIS)

    Zazula, J.M.

    1983-01-01

    The general purpose code BALTORO was written for coupling the three-dimensional Monte-Carlo /MC/ with the one-dimensional Discrete Ordinates /DO/ radiation transport calculations. The quantity of a radiation-induced /neutrons or gamma-rays/ nuclear effect or the score from a radiation-yielding nuclear effect can be analysed in this way. (author)

  17. Prostate biopsy after definitive treatment by interstitial iodine 125 implant or external beam radiation therapy

    International Nuclear Information System (INIS)

    Schellhammer, P.F.; el-Mahdi, A.M.; Higgins, E.M.; Schultheiss, T.E.; Ladaga, L.E.; Babb, T.J.

    1987-01-01

    The response to definitive radiation therapy of localized carcinoma of the prostate by iodine 125 implantation or external beam radiotherapy was monitored by examining specimens from biopsies performed after treatment. We analyzed 126 biopsy specimens obtained 18 months or more after treatment: 71 were obtained from 109 patients treated by iodine 125 and 55 from 197 patients treated by external beam radiotherapy. Thereafter, the disease status of these patients was examined at minimum 3-year intervals. No significant statistical difference was found between the negative specimen rates of the 2 treatment modalities: 46 of 71 (65 per cent) after iodine 125 implantation and 39 of 55 (71 per cent) after external beam radiotherapy were negative. To analyze the predictive value of biopsy results 103 patients whose prostatic examination results were normal at biopsy or who showed regression of tumor size and tumor induration after radiation were evaluated. The biopsy results from all patients were combined for analysis. Of 77 patients with negative biopsy specimens 16 (21 per cent) have had recurrent disease, compared to 17 of 26 (65 per cent) with positive biopsy specimens (p equals 0.00005). Of the 77 patients with negative biopsy specimens 7 (9 per cent) had local disease recurrence, compared to 12 of 26 (46 per cent) with a positive biopsy specimen (p equals 0.0001). The value of a positive specimen to predict failure remained significant with patients stratified by pre-treatment clinical stage and grade of the disease. Our results show that patients with positive specimens from the prostate who had been judged clinically by rectal examination to have responded to radiation therapy had a significantly increased incidence of local and distant failure compared to patients who had negative biopsy specimens

  18. Classical calculation of radiative lifetimes of atomic hydrogen in a homogeneous magnetic field

    International Nuclear Information System (INIS)

    Horbatsch, M.W.; Hessels, E.A.; Horbatsch, M.

    2005-01-01

    Radiative lifetimes of hydrogenic atoms in a homogeneous magnetic field of moderate strength are calculated on the basis of classical radiation. The modifications of the Keplerian orbits due to the magnetic field are incorporated by classical perturbation theory. The model is complemented by a classical radiative decay calculation using the radiated Larmor power. A recently derived highly accurate formula for the transition rate of a field-free hydrogenic state is averaged over the angular momentum oscillations caused by the magnetic field. The resulting radiative lifetimes for diamagnetic eigenstates classified by n,m and the diamagnetic energy shift C compare well with quantum results

  19. Randomized trial on external radiation therapy alone versus external radiation therapy followed by brachytherapy in early stage nasopharyngeal carcinoma with a long term result

    International Nuclear Information System (INIS)

    Gao Li; Yuan Zhiyong; Xu Guozhen; Li Suyan; Xiao Guangli; Cai Weiming

    2004-01-01

    Objective: To compare local control and toxicity in patients treated with external beam radiotherapy followed by intracavitary brachytherapy (BT) versus external beam radiotherapy alone (RT) for locally early stage nasopharyngeal carcinoma (NPC). Methods: From 1990 to 1997, 126 NPC patients staged T1 and T2 by 1992 Fuzhou Staging System (oropharynx, carotid sheath and soft tissue around cervical vertebral involvement excluded) were randomized into RT alone and RT followed BT groups. The two groups were comparable in age, gender, stage and pathology. The median follow-up was 112 months. T1 patients were randomized before the treatment into RT alone group of 66-70 Gy and RT plus BT with the dose of 56 Gy plus 10-16 Gy BT boost to the nasopharynx. For T2 patients, if MRI or CT showed no residual lesion in parapharyngeal space after 50 Gy, they were randomized into RT alone (median dose: 72 Gy) or RT of 66 Gy followed by 8-24 Gy BT boost (1-3 fractions over 1-3 weeks). Results: In RT group, 8 patients (13.1%) failed in primary site during the follow-up period, 7 (11%) in BT group. The 5-year local control rates was 86% for RT group and 88% for BT group (P=0.47). The 5-year overall survival rates were 83% and 84% (P=0.84), respectively. Ten patients (18%) in RT group (4 of grade I, 6 of grade II) and 7 patients (11%) in BT group (4 of grade I, 3 of grade II, P=0.31) developed radiation induced encephalopathy. The incidence of trismus was much lower in BT group than in RT group (26% versus 10%, P=0.02). No soft palate perforation or sphenoid necrosis were observed. Conclusion: Compared to conventional external beam radiotherapy, planned irradiation plus intracavitary brachytherapy not only can achieve similar local control and survival rates for locally early stage nasopharyngeal carcinoma, but also decrease irradiation dose and the trismus incidence. (authors)

  20. Cost and effectiveness of decontamination strategies in radiation contaminated areas in Fukushima in regard to external radiation dose.

    Science.gov (United States)

    Yasutaka, Tetsuo; Naito, Wataru; Nakanishi, Junko

    2013-01-01

    The objective of the present study is to evaluate the cost and effectiveness of decontamination strategies in the special decontamination areas in Fukushima in regard to external radiation dose. A geographical information system (GIS) was used to relate the predicted external dose in the affected areas to the number of potential inhabitants and the land use in the areas. A comprehensive review of the costs of various decontamination methods was conducted as part of the analysis. The results indicate that aerial decontamination in the special decontamination areas in Fukushima would be effective for reducing the air dose rate to the target level in a short period of time in some but not all of the areas. In a standard scenario, analysis of cost and effectiveness suggests that decontamination costs for agricultural areas account for approximately 80% of the total decontamination cost, of which approximately 60% is associated with storage. In addition, the costs of decontamination per person per unit area are estimated to vary greatly. Appropriate selection of decontamination methods may significantly decrease decontamination costs, allowing more meaningful decontamination in terms of the limited budget. Our analysis can help in examining the prioritization of decontamination areas from the viewpoints of cost and effectiveness in reducing the external dose. Decontamination strategies should be determined according to air dose rates and future land-use plans.

  1. Automated calculation of myocardial external efficiency from a single 11C-acetate PET/CT scan

    DEFF Research Database (Denmark)

    Harms, Hans; Tolbod, Lars Poulsen; Hansson, Nils Henrik

    of this study was to develop and validate an automated method of calculating MEE from a single dynamic 11C-acetate PETscan. Methods: 21 subjects underwent a dynamic 27 min 11C-acetate PETscan on a Siemens Biograph TruePoint 64 PET/CTscanner. Using cluster analysis, the LV-aortic time-activity curve (TACLV......). Conclusion: Myocardial efficiencycanbe derived directly andautomatically froma single dynamic 11C-acetate PET scan. This eliminates the need for a separate CMR scan and eliminates any potential errors due to different loading conditions between CMR and PETscans.......Background: Dynamic PETwith 11C-acetate can be used to assess myocardial oxygen use which in turn is usedto calculate myocardial external efficiency (MEE), anearly marker of heart failure. MEE is defined as the ratio of total work (TW) and total energy use (TE). Calculation of TW and TE requires...

  2. Biochemical and morphological changes in rat lung tissue under the influence of external ionizing radiation

    International Nuclear Information System (INIS)

    Uzlenkova, N.Je.; Mamotyuk, Je.M.; Gusakova, V.A.; Kononenko, O.K.

    2006-01-01

    Single external x-ray exposure at minimum and mean lethal doses was established to cause a long activation of biochemical processes in the connective tissue of the rat lungs. Morphological and ultrastructure changes in the tissue of the lungs at early terms after x-ray and gamma-radiation exposure were due to development of destructive and degenerative reactions. The long-term changes were characterized by growth of connective tissue and formation of areas of fibrous changes in the structure of the lungs

  3. Measurement protocols for performance testing of dosimetry services for external radiations

    International Nuclear Information System (INIS)

    1993-01-01

    In the Health and Safety Executive's ''Requirements for the Approval of Dosimetry Services under the Ionising Radiations Regulations 1985'', it is stipulated that dosimetry services seeking approval must show that they have successfully completed a performance test. The services must arrange for the tests to be carried out on application and thereafter every 18 months, by a laboratory which has received accreditation from the National Measurement Accreditation Service (NAMAS) for the whole performance testing activity. The performance tests must be carried out to published protocols and the purpose here is to provide protocols for external, whole body film and TLD dosimetry services, and for skin and extremity dosimetry services. (Author)

  4. Aberration analysis calculations for synchrotron radiation beamline design

    International Nuclear Information System (INIS)

    McKinney, W.R.; Howells, M.; Padmore, H.A.

    1997-09-01

    The application of ray deviation calculations based on aberration coefficients for a single optical surface for the design of beamline optical systems is reviewed. A systematic development is presented which allows insight into which aberration may be causing the rays to deviate from perfect focus. A new development allowing analytical calculation of line shape is presented

  5. Modification and validation of an analytical source model for external beam radiotherapy Monte Carlo dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, Scott E., E-mail: sedavids@utmb.edu [Radiation Oncology, The University of Texas Medical Branch, Galveston, Texas 77555 (United States); Cui, Jing [Radiation Oncology, University of Southern California, Los Angeles, California 90033 (United States); Kry, Stephen; Ibbott, Geoffrey S.; Followill, David S. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York 10065 (United States); Vicic, Milos [Department of Applied Physics, University of Belgrade, Belgrade 11000 (Serbia); White, R. Allen [Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2016-08-15

    Purpose: A dose calculation tool, which combines the accuracy of the dose planning method (DPM) Monte Carlo code and the versatility of a practical analytical multisource model, which was previously reported has been improved and validated for the Varian 6 and 10 MV linear accelerators (linacs). The calculation tool can be used to calculate doses in advanced clinical application studies. One shortcoming of current clinical trials that report dose from patient plans is the lack of a standardized dose calculation methodology. Because commercial treatment planning systems (TPSs) have their own dose calculation algorithms and the clinical trial participant who uses these systems is responsible for commissioning the beam model, variation exists in the reported calculated dose distributions. Today’s modern linac is manufactured to tight specifications so that variability within a linac model is quite low. The expectation is that a single dose calculation tool for a specific linac model can be used to accurately recalculate dose from patient plans that have been submitted to the clinical trial community from any institution. The calculation tool would provide for a more meaningful outcome analysis. Methods: The analytical source model was described by a primary point source, a secondary extra-focal source, and a contaminant electron source. Off-axis energy softening and fluence effects were also included. The additions of hyperbolic functions have been incorporated into the model to correct for the changes in output and in electron contamination with field size. A multileaf collimator (MLC) model is included to facilitate phantom and patient dose calculations. An offset to the MLC leaf positions was used to correct for the rudimentary assumed primary point source. Results: Dose calculations of the depth dose and profiles for field sizes 4 × 4 to 40 × 40 cm agree with measurement within 2% of the maximum dose or 2 mm distance to agreement (DTA) for 95% of the data

  6. CALCULATION OF THE COHERENT RADIATION IMPDENACE FROM A WIGGLER

    International Nuclear Information System (INIS)

    Wu, J

    2004-01-01

    Most studies of coherent synchrotron radiation (CSR) have considered only the radiation from independent dipole magnets. However, in the damping rings of future linear colliders and many high luminosity factories, a large fraction of the radiation power will be emitted in damping wigglers. In this paper, the longitudinal wakefield and impedance due to CSR in a wiggler are derived in the limit of a large wiggler parameter K. After an appropriate scaling, the results can be expressed in terms of universal functions, which are independent of K. Analytical asymptotic results are obtained for the wakefield in the limit of large and small distances, and for the impedance in the limit of small and high frequencies

  7. Calculated radiation doses from radionuclides brought to the surface if future drilling intercepts the WIPP repository and pressurized brine

    International Nuclear Information System (INIS)

    Channell, J.K.

    1982-01-01

    This report describes a scenario in which an exploratory borehole connects an underlying brine reservoir with the repository and results in saturation of the waste storage area. A subsequent borehole brings portions of this radionuclide contaminated brine to the surface. Radiation odses are calculated for time periods of 125, 400, and 1000 years after repository closing for the following: (1) external radiation doses for workers at the borehole location; (2) inhalation doses for workers at the borehole location; (3) external and inhalation doses for a resident located 360 meters downwind; (4) ingestion doses for the downwind resident from locally grown produce, milk, and meat; and (5) population doses from inhalation within a 50-mile radius. The probability of the various calculated doses occurring was estimated. Probability was included in the report because of a belief that probability considerations are useful in evaluating the acceptability of unlikely events and to encourage others to provide a more detailed evaluation using more sophisticated methodology. Since the probabilities presented in this report were calculated using a simple methodology, with some parameter values chosen arbitrarily, they should be considered as approximate examples, not accurate numbers. The reasonableness of the scenario and the significance of the results are also discussed

  8. Implementation and training methodology of subcritical reactors neutronic calculations triggered by external neutron source and applications

    International Nuclear Information System (INIS)

    Carluccio, Thiago

    2011-01-01

    This works had as goal to investigate calculational methodologies on subcritical source driven reactor, such as Accelerator Driven Subcritical Reactor (ADSR) and Fusion Driven Subcritical Reactor (FDSR). Intense R and D has been done about these subcritical concepts, mainly due to Minor Actinides (MA) and Long Lived Fission Products (LLFP) transmutation possibilities. In this work, particular emphasis has been given to: (1) complement and improve calculation methodology with neutronic transmutation and decay capabilities and implement it computationally, (2) utilization of this methodology in the Coordinated Research Project (CRP) of the International Atomic Energy Agency Analytical and Experimental Benchmark Analysis of ADS and in the Collaborative Work on Use of Low Enriched Uranium in ADS, especially in the reproduction of the experimental results of the Yalina Booster subcritical assembly and study of a subcritical core of IPEN / MB-01 reactor, (3) to compare different nuclear data libraries calculation of integral parameters, such as k eff and k src , and differential distributions, such as spectrum and flux, and nuclides inventories and (4) apply the develop methodology in a study that may help future choices about dedicated transmutation system. The following tools have been used in this work: MCNP (Monte Carlo N particle transport code), MCB (enhanced version of MCNP that allows burnup calculation) and NJOY to process nuclear data from evaluated nuclear data files. (author)

  9. A new programmable zone dosimeter for operational monitoring and measurement of external gamma radiation

    International Nuclear Information System (INIS)

    Toledo Acosta, Rene; Arteche Diaz, Raul; Mesa Perez, Guillermo; Fernandez Llanez, Sandra; Tamayo Garcia, Jose Antonio; Alonso Villanueva, Gilberto

    2010-01-01

    The detection and the measurement of the nuclear radiations have turn into an important item in the nuclear detectors application and specifically the Geiger Muller ones. Coming from theirs high detection sensibility, robust construction and relative simplicity of the associated circuit, the Geiger Tubes are still one of the most widely used detectors in all the application areas regarding physics and nuclear investigations A new design instrument is presented to be measures the ambient dose of external (gamma) radiation since 10 mSv/h. It consists of three elements: Geiger-Muller detector, the electronic board for the acquisition and control and the application software. The instrument communicates trough a USB interface to the Personal Computer only for adjust calibration parameters. The software was developed in the C programming language using PICC4, 08 compilers. (author)

  10. Vestibular apparatus disorders after external radiation therapy for head and neck cancers

    International Nuclear Information System (INIS)

    Gabriele, P.; Orecchia, R.; Sannazzari, G.L.; Magnano, M.; Albera, R.

    1992-01-01

    External irradiation of different head and neck cancers may involve parts of the ear. The vestibular function of 25 patients in which the inner ear was comprised in the irradiated volume was investigated by electronystagmography (ENG). Doses administered (3/5 with vertigo) showed vestibular abnormalities to ENG (44% of the total). Altered responses to specific test were as follows : 6 patients to the bithermal caloric stimulation, to pendular-sinusoidal 2, and the other 3 to both of them. Patients were evaluated 3 and 6 months after ending of the radiation therapy course. At the 1st evaluation, abnormalities to caloric test were noted in 3 patients (12%) and to sinusoidal rotary test in 1 patient (4%). At the second rates of abnormal response increased to 36 and 20% respectively. Vestibular disorders seemed to be scantely related to total radiation dose. Data of literature are discussed in order to identify possible implications on treatment planning. (author). 33 refs., 3 tabs

  11. Cytogenetic studies in women with menstrual disturbances, working in an environment of ionizing radiation (external irradiation)

    International Nuclear Information System (INIS)

    Marinova, G.; Dimcheva, M.; Kyncheva, V.

    1976-01-01

    Cytogenetic studies of peripheral blood lymphocytes involved a sample of 30 female radiation workers with menstrual disorders from a total of 400 subjects (female physicians, laboratory technicians, and attendant personnel) included in dispensary polyclinic supervision records for a five-year period. Clinical conditions were distributed as follows: 16 patients, with oligomenorrhea; 8, with irregular bleedings; 3, with hypermenorrhea; 2, with a history of obstetric pathology; and 1, with ovarian cyst. Length of occupational experience in a radiation environment (external exposure) varied from 2 to 25 years; patient age, from 21 to 45 years. Chromosome anomalies were found in 17 of the 30 subjects investigated. Types of chromosome abnormalities detected: aneuploidy, fragments and gaps, and in one case, dicentric aberrations. Amounts of chromosome damage induced were shown to be related to years at risk. (A.B.)

  12. The Atmospheric Radiation Measurement Program and interfaces with external data sources

    International Nuclear Information System (INIS)

    Stokes, G.M.; Cress, T.S.; Melton, R.B.

    1993-10-01

    The Atmospheric Radiation Measurement (ARM) Program is the Department of Energy's major field project in support of its global change research program. Its objective is to improve the performance of cloud and radiation models and parameterizations in general circulation models (GCMs) used for climate research. The data produced by ARM will be handled and maintained to satisfy the research needs of the program and to be accessible and usable by the general research and academic communities. In addition to data from field instrumentation, ARM Science Team needs include a substantial amount of data from outside the ARM Program (''external data''), which will be acquired and provided routinely through the ARM data system. With respect to data archival and sharing, the ARM Program reflects the objectives delineated by the US Global Change. The purpose of this presentation is to summarize the conceptual designs embodied in the ARM data system and the status of its implementation

  13. Calculations in the Wheeler-Feynman absorber theory of radiation

    International Nuclear Information System (INIS)

    Balaji, K.S.

    1986-01-01

    One dimensional computer aided calculations were done to find the self consistent solutions for various absorber configurations in the context of the Wheeler-Feynman absorber theory, wherein every accelerating charge is assumed to produce a time symmetric combination of advanced and retarded fields. These calculations picked out the so called outerface solution for incomplete absorbers and showed that advanced as well as retarded signals interact with matter in the same manner as in the full retarded theory. Based on these calculations, the Partridge experiment and the Schmidt-Newman experiment were ruled out as tests of the absorber theory. An experiment designed to produce and detect advanced effects is proposed, based on more one-dimensional calculations

  14. Lithium delays the radiation-induced apoptotic process in external granule cells of mouse cerebellum

    International Nuclear Information System (INIS)

    Inouye, Minoru; Yamamura, Hideki; Nakano, Atsuhiro.

    1995-01-01

    Proliferating cells of the external granular layer (EGL) in the developing cerebellum are highly sensitive to ionizing radiation. We examined the effect of lithium, an inhibitor of intracellular signaling, on the manifestation of radiation-induced apoptosis. Newborn mice were exposed to 0.5 Gy gamma-irradiation alone, or first were treated with lithium (10 μmol/g, SC) then given 0.5 Gy irradiation 2 hr later. The EGL was examined histologically for apoptosis at various times after treatment. Apoptotic cells increased rapidly, peaked (about 14%) 6 hr after irradiation, then decreased gradually to the control level by 24 hr. Prior treatment with lithium delayed the manifestation of apoptosis, the peak appearing at 12 hr. The disappearance of dead cells was delayed for about one day. The lithium concentration in the whole brain increased rapidly, being 30 μg/g at the time of irradiation and remaining at more than 40 μg/g for 40 hr. Lithium is reported to inhibit guanine-nucleotide binding to G proteins as well as phosphoinositide turnover. Of the variety of lesions induced by radiation, DNA double strand breaks are the most important source of cell lethality. The present findings, however, suggest that cyclic AMP-mediated and/or phosphoinositide-mediated signaling systems regulate radiation-induced apoptosis. (author)

  15. Lithium delays the radiation-induced apoptotic process in external granule cells of mouse cerebellum.

    Science.gov (United States)

    Inouye, M; Yamamura, H; Nakano, A

    1995-09-01

    Proliferating cells of the external granular layer (EGL) in the developing cerebellum are highly sensitive to ionizing radiation. We examined the effect of lithium, an inhibitor of intracellular signaling, on the manifestation of radiation-induced apoptosis. Newborn mice were exposed to 0.5 Gy gamma-irradiation alone, or first were treated with lithium (10 mumol/g, SC) then given 0.5 Gy irradiation 2 hr later. The EGL was examined histologically for apoptosis at various times after treatment. Apoptotic cells increased rapidly, peaked (about 14%) 6 hr after irradiation, then decreased gradually to the control level by 24 hr. Prior treatment with lithium delayed the manifestation of apoptosis, the peak appearing at 12 hr. The disappearance of dead cells was delayed for about one day. The lithium concentration in the whole brain increased rapidly, being 30 micrograms/g at the time of irradiation and remaining at more than 40 micrograms/g for 40 hr. Lithium is reported to inhibit guanine-nucleotide binding to G proteins as well as phosphoinositide turnover. Of the variety of lesions induced by radiation, DNA double strand breaks are the most important source of cell lethality. The present findings, however, suggest that cyclic AMP-mediated and/or phosphoinositidemediated signaling systems regulate radiation-induced apoptosis.

  16. Lithium delays the radiation-induced apoptotic process in external granule cells of mouse cerebellum

    Energy Technology Data Exchange (ETDEWEB)

    Inouye, Minoru; Yamamura, Hideki [Nagoya Univ. (Japan). Research Inst. of Environmental Medicine; Nakano, Atsuhiro

    1995-09-01

    Proliferating cells of the external granular layer (EGL) in the developing cerebellum are highly sensitive to ionizing radiation. We examined the effect of lithium, an inhibitor of intracellular signaling, on the manifestation of radiation-induced apoptosis. Newborn mice were exposed to 0.5 Gy gamma-irradiation alone, or first were treated with lithium (10 {mu}mol/g, SC) then given 0.5 Gy irradiation 2 hr later. The EGL was examined histologically for apoptosis at various times after treatment. Apoptotic cells increased rapidly, peaked (about 14%) 6 hr after irradiation, then decreased gradually to the control level by 24 hr. Prior treatment with lithium delayed the manifestation of apoptosis, the peak appearing at 12 hr. The disappearance of dead cells was delayed for about one day. The lithium concentration in the whole brain increased rapidly, being 30 {mu}g/g at the time of irradiation and remaining at more than 40 {mu}g/g for 40 hr. Lithium is reported to inhibit guanine-nucleotide binding to G proteins as well as phosphoinositide turnover. Of the variety of lesions induced by radiation, DNA double strand breaks are the most important source of cell lethality. The present findings, however, suggest that cyclic AMP-mediated and/or phosphoinositide-mediated signaling systems regulate radiation-induced apoptosis. (author).

  17. Summary of Building Protection Factor Studies for External Exposure to Ionizing Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kane, Jave [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nasstrom, John [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Homann, Steve [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pobanz, Brenda [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-02-17

    Radiation dose assessments are used to help inform decisions to minimize health risks in the event of an atmospheric release of radioactivity including, for example, from a Radiological Dispersal Device, an Improvised Nuclear Device detonation, or a Nuclear Power Plant accident. During these incidents, radiation dose assessments for both indoor and outdoor populations are needed to make informed decisions. These dose assessments inform emergency plans and decisions including, for example, identifying areas in which people should be sheltered and determining when controlled population evacuations should be made. US dose assessment methodologies allow consideration of the protection, and therefore dose reduction, that buildings provide their occupants. However, these methodologies require an understanding of the protection provided by various building types that is currently lacking. To help address this need, Lawrence Livermore National Laboratory, in cooperation with Sandia National Laboratories and the Nuclear Regulatory Commission, was tasked with (a) identifying prior building protection studies, (b) extracting results relevant to US building construction, and (c) summarizing building protection by building type. This report focuses primarily on the protection against radiation from outdoor fallout particles (external gamma radiation).

  18. Osteochondromas and growth retardation secondary to externally or internally administered radiation in childhood

    Energy Technology Data Exchange (ETDEWEB)

    Marcovici, Peter A. [UCSD Medical Center, Department of Radiology, San Diego, CA (United States); Berdon, Walter E. [Morgan Stanley Children' s Hospital of New York, Department of Radiology, New York, NY (United States); Liebling, Melissa S. [Hackensack University Medical Center, Department of Radiology, Hackensack, NJ (United States)

    2007-03-15

    For over five decades, osteochondromas (exostoses) and associated growth retardation have been known to be caused by radiation damage to the growing skeleton.Patients can be divided into three exposure groups. Group I received external beam radiation therapy primarily for the treatment of childhood cancers (typical dose 3,500 cGy), and 6-20% developed osteochondromas and growth retardation within the radiation portal. Group II consists of recently described patients who received total body irradiation in preparation for bone marrow transplant (typical dose: 800-1,200 cGy), and about 20% developed osteochondromas and growth retardation. Group III consists of 206 German children who in the 1940s and early 1950s received intravenous radioactive Peteosthor (Ra-224) to treat bone tuberculosis (estimated typical dose: 1,000-2,000 cGy), and 14% developed osteochondromas and growth retardation, among other benign and malignant sequelae. Combining these three exposure groups, osteochondromas and growth retardation develop in at least 6-20% of children who receive therapeutic radiation to their growing skeletons. (orig.)

  19. Summary of Building Protection Factor Studies for External Exposure to Ionizing Radiation

    International Nuclear Information System (INIS)

    Dillon, Michael B.; Kane, Jave; Nasstrom, John; Homann, Steve; Pobanz, Brenda

    2016-01-01

    Radiation dose assessments are used to help inform decisions to minimize health risks in the event of an atmospheric release of radioactivity including, for example, from a Radiological Dispersal Device, an Improvised Nuclear Device detonation, or a Nuclear Power Plant accident. During these incidents, radiation dose assessments for both indoor and outdoor populations are needed to make informed decisions. These dose assessments inform emergency plans and decisions including, for example, identifying areas in which people should be sheltered and determining when controlled population evacuations should be made. US dose assessment methodologies allow consideration of the protection, and therefore dose reduction, that buildings provide their occupants. However, these methodologies require an understanding of the protection provided by various building types that is currently lacking. To help address this need, Lawrence Livermore National Laboratory, in cooperation with Sandia National Laboratories and the Nuclear Regulatory Commission, was tasked with (a) identifying prior building protection studies, (b) extracting results relevant to US building construction, and (c) summarizing building protection by building type. This report focuses primarily on the protection against radiation from outdoor fallout particles (external gamma radiation).

  20. Comparison of dose calculation algorithms for treatment planning in external photon beam therapy for clinical situations

    DEFF Research Database (Denmark)

    Knöös, Tommy; Wieslander, Elinore; Cozzi, Luca

    2006-01-01

    to the fields. A Monte Carlo calculated algorithm input data set and a benchmark set for a virtual linear accelerator have been produced which have facilitated the analysis and interpretation of the results. The more sophisticated models in the type b group exhibit changes in both absorbed dose and its...... distribution which are congruent with the simulations performed by Monte Carlo-based virtual accelerator....

  1. Estimation of dose from exposure to external radiation in the environment

    International Nuclear Information System (INIS)

    Abe, Siro; Fujitaka, Kazunobu

    1978-01-01

    Meteorological factors which influence the external radiation were analysed. Attention was paid to the relationship between the concentration of the radioactive aerosol and the outdoor radiation level. Twelve kinds of data were obtained at Kumatori Site of Kyoto University. The mean diurnal variation and annual variation of each factors were obtained from the data of 25 months periods from August 1974 to August 1976. Outstanding was the result that the outdoor gamma radiation varied just slightly in spite of the large variation of the airborne activities and others. It implies that the individual effect due to the factor would compensate and cancel each other. Otherwise the major contribution on the variation might distribute at random with respect to time. Contrary to the apparent independence of the outdoor gamma radiation level of the airborne activity, however, the partial correlation coefficient between them was not negligibly small. Analysis of each time series of individual data has revealed that the rainfall has the largest influence on the variation of the outdoor gamma radiation level particularly in its initial period. Airborne activity was also revealed to have a strong connection with the atmospheric stability and the wind velocity though it depends on the rainfall just a little. The atmospheric stability could be expressed by the vertical gradient of the atmospheric temperature which is strongest at the ''inversion''. However problem remains as to the nature of the wind. Which of the atmospheric turbulence and the prevailing wind corresponds to the wind here will have to be analysed referring to the large scale weather charts. Regression analysis showed that the atmospheric temperature was the essential cause of the variation of the radiation level. (author)

  2. Radiation doses by radiation diagnostics at the border of a hospital. Calculation model for Nuclear Energy Law regulations

    International Nuclear Information System (INIS)

    Shapiro, B.; Thijssen, T.; De Jong, R.

    2000-01-01

    According to the Nuclear Energy Law in the Netherlands radiation doses at the border of a specific institute (e.g. hospitals) must be determined which can not simply be done by measurements. In this article a model calculation for radiation diagnostics is described

  3. First-principles calculation of transport property in nano-devices under an external magnetic field

    International Nuclear Information System (INIS)

    Chen Jingzhe; Zhang Jin; Han Rushan

    2008-01-01

    The mesoscopic quantum interference phenomenon (QIP) can be observed and behaves as the oscillation of conductance in nano-devices when the external magnetic field changes. Excluding the factor of impurities or defects, specific QIP is determined by the sample geometry. We have improved a first-principles method based on the matrix Green's function and the density functional theory to simulate the transport behaviour of such systems under a magnetic field. We have studied two kinds of QIP: universal conductance fluctuation (UCF) and Aharonov–Bohm effect (A–B effect). We find that the amplitude of UCF is much smaller than the previous theoretical prediction. We have discussed the origin of difference and concluded that due to the failure of ergodic hypothesis, the ensemble statistics is not applicable, and the conductance fluctuation is determined by the flux-dependent density of states (DOSs). We have also studied the relation between the UCF and the structure of sample. For a specific structure, an atomic circle, the A–B effect is observed and the origin of the oscillation is also discussed

  4. General Method for Calculating the Response and Noise Spectra of Active Fabry-Perot Semiconductor Waveguides With External Optical Injection

    DEFF Research Database (Denmark)

    Blaaberg, Søren; Mørk, Jesper

    2009-01-01

    We present a theoretical method for calculating small-signal modulation responses and noise spectra of active Fabry-Perot semiconductor waveguides with external light injection. Small-signal responses due to either a modulation of the pump current or due to an optical amplitude or phase modulatio...... amplifiers and an injection-locked laser. We also demonstrate the applicability of the method to analyze slow and fast light effects in semiconductor waveguides. Finite reflectivities of the facets are found to influence the phase changes of the injected microwave-modulated light....

  5. Verification by the FISH translocation assay of historic doses to Mayak workers from external gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sotnik, Natalia V.; Azizova, Tamara V. [Southern Urals Biophysics Institute (SUBI), Ozyorsk, Chelyabinsk Region (Russian Federation); Darroudi, Firouz [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands); College of North Atlantic, Department of Health Science, Centre for Human Safety and Environmental Research, Doha (Qatar); Ainsbury, Elizabeth A.; Moquet, Jayne E.; Lloyd, David C.; Hone, Pat A.; Edwards, Alan A. [Public Health England, Chilton, Oxfordshire (United Kingdom); Fomina, Janna [Leiden University Medical Center, Department of Toxicogenetics, Leiden (Netherlands)

    2015-11-15

    The aim of this study was to apply the fluorescence in situ hybridization (FISH) translocation assay in combination with chromosome painting of peripheral blood lymphocytes for retrospective biological dosimetry of Mayak nuclear power plant workers exposed chronically to external gamma radiation. These data were compared with physical dose estimates based on monitoring with badge dosimeters throughout each person's working life. Chromosome translocation yields for 94 workers of the Mayak production association were measured in three laboratories: Southern Urals Biophysics Institute, Leiden University Medical Center and the former Health Protection Agency of the UK (hereinafter Public Health England). The results of the study demonstrated that the FISH-based translocation assay in workers with prolonged (chronic) occupational gamma-ray exposure was a reliable biological dosimeter even many years after radiation exposure. Cytogenetic estimates of red bone marrow doses from external gamma rays were reasonably consistent with dose measurements based on film badge readings successfully validated in dosimetry system ''Doses-2005'' by FISH, within the bounds of the associated uncertainties. (orig.)

  6. Permissible dose from external sources of ionizing radiation. Recommendations of the National Committee on Radiation Protection. Handbook 59

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1954-09-24

    The Advisory Committee on X-ray and Radium Protection was formed in 1929 upon the recommendation of the International Commission on Radiological Protection, under the sponsorship of the National Bureau of Standards, and with the cooperation of the leading radiological organizations. The small committee functioned effectively until the advent of atomic energy, which introduced a large number of new and serious problems in the field of radiation protection. The present report deals primarily with the protection of persons occupationally exposed to ionizing radiation from external sources. An attempt has been made to cover most of the situations encountered in practice. However, it has not always been possible to make recommendations in quantitative terms. In such cases the recommendations are intended to serve as practical guides. The recommendations are based on presently available information and cannot be regarded as permanent. For this reason and on general grounds it is strongly recommended that exposure to radiation be kept at the lowest practicable level in all cases.

  7. Permissible dose from external sources of ionizing radiation. Recommendations of the National Committee on Radiation Protection. Handbook 59

    International Nuclear Information System (INIS)

    1954-01-01

    The Advisory Committee on X-ray and Radium Protection was formed in 1929 upon the recommendation of the International Commission on Radiological Protection, under the sponsorship of the National Bureau of Standards, and with the cooperation of the leading radiological organizations. The small committee functioned effectively until the advent of atomic energy, which introduced a large number of new and serious problems in the field of radiation protection. The present report deals primarily with the protection of persons occupationally exposed to ionizing radiation from external sources. An attempt has been made to cover most of the situations encountered in practice. However, it has not always been possible to make recommendations in quantitative terms. In such cases the recommendations are intended to serve as practical guides. The recommendations are based on presently available information and cannot be regarded as permanent. For this reason and on general grounds it is strongly recommended that exposure to radiation be kept at the lowest practicable level in all cases

  8. The patient radiation protection in external radiotherapy: specificity and methods; La radioprotection du patient en radiotherapie externe: specificites et methodes

    Energy Technology Data Exchange (ETDEWEB)

    Beauvais March, H. [Hopital Val de Grace, 75 - Paris (France)

    1999-07-01

    The daily use of high level radiation doses to fight against carcinomas has often led to consider radiation protection as a marginal problem, in this area. But the therapeutic advances, by increasing the life time and life quality have made the side effects unacceptable and revealed the appearance of radioinduced carcinomas. So, it is necessary to practice a patient radiation protection. The general principles of radiation protection are applicable to radiotherapy. (justification, optimization and dose limit, planning of the treatment, quality control of installations). (N.C.)

  9. TRUST. I. A 3D externally illuminated slab benchmark for dust radiative transfer

    Science.gov (United States)

    Gordon, K. D.; Baes, M.; Bianchi, S.; Camps, P.; Juvela, M.; Kuiper, R.; Lunttila, T.; Misselt, K. A.; Natale, G.; Robitaille, T.; Steinacker, J.

    2017-07-01

    Context. The radiative transport of photons through arbitrary three-dimensional (3D) structures of dust is a challenging problem due to the anisotropic scattering of dust grains and strong coupling between different spatial regions. The radiative transfer problem in 3D is solved using Monte Carlo or Ray Tracing techniques as no full analytic solution exists for the true 3D structures. Aims: We provide the first 3D dust radiative transfer benchmark composed of a slab of dust with uniform density externally illuminated by a star. This simple 3D benchmark is explicitly formulated to provide tests of the different components of the radiative transfer problem including dust absorption, scattering, and emission. Methods: The details of the external star, the slab itself, and the dust properties are provided. This benchmark includes models with a range of dust optical depths fully probing cases that are optically thin at all wavelengths to optically thick at most wavelengths. The dust properties adopted are characteristic of the diffuse Milky Way interstellar medium. This benchmark includes solutions for the full dust emission including single photon (stochastic) heating as well as two simplifying approximations: One where all grains are considered in equilibrium with the radiation field and one where the emission is from a single effective grain with size-distribution-averaged properties. A total of six Monte Carlo codes and one Ray Tracing code provide solutions to this benchmark. Results: The solution to this benchmark is given as global spectral energy distributions (SEDs) and images at select diagnostic wavelengths from the ultraviolet through the infrared. Comparison of the results revealed that the global SEDs are consistent on average to a few percent for all but the scattered stellar flux at very high optical depths. The image results are consistent within 10%, again except for the stellar scattered flux at very high optical depths. The lack of agreement between

  10. Development and verification of an excel program for calculation of monitor units for tangential breast irradiation with external photon beams

    International Nuclear Information System (INIS)

    Woldemariyam, M.G.

    2015-07-01

    The accuracy of MU calculation performed with Prowess Panther TPS (for Co-60) and Oncentra (for 6MV and 15MV x-rays) for tangential breast irradiation was evaluated with measurements made in an anthropomorphic phantom using calibrated Gafchromic EBT2 films. Excel programme which takes in to account external body surface irregularity of an intact breast or chest wall (hence absence of full scatter condition) using Clarkson’s sector summation technique was developed. A single surface contour of the patient obtained in a transverse plane containing the MU calculation point was required for effective implementation of the programme. The outputs of the Excel programme were validated with the respective outputs from the 3D treatment planning systems. The variations between the measured point doses and their calculated counterparts by the TPSs were within the range of -4.74% to 4.52% (mean of -1.33% and SD of 2.69) for the prowess panther TPS and -4.42% to 3.14% (mean of -1.47% and SD of -3.95) for the Oncentra TPS. The observed degree of deviation may be attributed to limitations of the dose calculation algorithm within the TPSs, set up inaccuracies of the phantom during irradiation and inherent uncertainties associated with radiochromic film dosimetry. The percentage deviations between MUs calculated with the two TPSs and the Excel program were within the range of -3.45% and 3.82% (mean of 0.83% and SD of 2.25). The observed percentage deviations are within the 4% action level recommended by TG-114. This indicates that the Excel program can be confidently employed for calculation of MUs for 2D planned tangential breast irradiations or to independently verify MUs calculated with another calculation methods. (au)

  11. Implication of new CEC recommendations for individual monitoring for external radiation doses to the skin and the extremities

    DEFF Research Database (Denmark)

    Christensen, P.; Julius, H.W.; Marshall, T.O.

    1991-01-01

    A drafting group consisting of the above authors has assisted the CEC in revising the CEC document Technical Recommendations for Monitoring the Exposure to Individuals to External Radiation, EUR 5287, published in 1975. The paper highlights sections of the revised version relating particularly...... to irradiation of the skin and the extremities and focusses on problems connected to exposure to weakly penetrating radiations. Concepts of individual monitoring for external radiation exposures to the skin of the whole body and to the extremities are discussed and guidance is given as regards dose quantities...

  12. Problems with regard to occupational exposure of external personnel (section 15 of the German Radiation Protection Ordinance)

    International Nuclear Information System (INIS)

    Roth, W.

    2002-01-01

    The annual radiation dose to the group of external personnel working in nuclear facilities accounts for more than 39% of the total annual collective dose of all occupationally exposed persons in Germany. This is a fact causing problems for plant operators employing external personnel as well as the sending companies, with respect to compliance with the radiation protection regulations. The amended German Radiation Protection Ordinance does not really make things easier in this respect, but in fact is expected to aggravate the situation in the course of increasing globalisation in the industrial sector. (orig./CB) [de

  13. Radiation effect calculation means of the Crisis Technical Center of the Nuclear Safety and Protection Institut

    International Nuclear Information System (INIS)

    Crabol, B.; Manesse, D.; Robeau, D.

    1989-07-01

    The available calculation tools of the Crisis Technical Center (CTC), for the analysis and evaluation of radiation effects from a nuclear accident, are presented. The CTC calculation unit depends on local means, and on the National Meteorology system, in order to collect the data needed for the atmospheric waste diffusion evaluation. For the radiation dose calculations, plotters and software allowing the analysis of all waste Kinetics and all the meteorological conditions are available. The work developed by CTC calculation unit enables an easy application of the calculation tools as well as the results obtention. Images from data bases are provided to complete the obtained results [fr

  14. Monte Carlo Calculation of the Radiation Field at Aircraft Altitudes

    Energy Technology Data Exchange (ETDEWEB)

    Roesler, Stefan

    2001-08-24

    Energy spectra of secondary cosmic rays are calculated for aircraft altitudes and a discrete set of solar modulation parameters and rigidity cutoff values covering all possible conditions. The calculations are based on the Monte Carlo code FLUKA and on the most recent information on the interstellar cosmic ray flux including a detailed model of solar modulation. Results are compared to a large variety of experimental data obtained on ground and aboard of aircrafts and balloons, such as neutron, proton, and muon spectra and yields of charged particles. Furthermore, particle fluence is converted into ambient dose equivalent and effective dose and the dependence of these quantities on height above sea level, solar modulation, and geographic location is studied. Finally, calculated dose equivalent is compared to results of comprehensive measurements performed aboard of aircrafts.

  15. Development and external multicenter validation of Chinese Prostate Cancer Consortium prostate cancer risk calculator for initial prostate biopsy.

    Science.gov (United States)

    Chen, Rui; Xie, Liping; Xue, Wei; Ye, Zhangqun; Ma, Lulin; Gao, Xu; Ren, Shancheng; Wang, Fubo; Zhao, Lin; Xu, Chuanliang; Sun, Yinghao

    2016-09-01

    Substantial differences exist in the relationship of prostate cancer (PCa) detection rate and prostate-specific antigen (PSA) level between Western and Asian populations. Classic Western risk calculators, European Randomized Study for Screening of Prostate Cancer Risk Calculator, and Prostate Cancer Prevention Trial Risk Calculator, were shown to be not applicable in Asian populations. We aimed to develop and validate a risk calculator for predicting the probability of PCa and high-grade PCa (defined as Gleason Score sum 7 or higher) at initial prostate biopsy in Chinese men. Urology outpatients who underwent initial prostate biopsy according to the inclusion criteria were included. The multivariate logistic regression-based Chinese Prostate Cancer Consortium Risk Calculator (CPCC-RC) was constructed with cases from 2 hospitals in Shanghai. Discriminative ability, calibration and decision curve analysis were externally validated in 3 CPCC member hospitals. Of the 1,835 patients involved, PCa was identified in 338/924 (36.6%) and 294/911 (32.3%) men in the development and validation cohort, respectively. Multivariate logistic regression analyses showed that 5 predictors (age, logPSA, logPV, free PSA ratio, and digital rectal examination) were associated with PCa (Model 1) or high-grade PCa (Model 2), respectively. The area under the curve of Model 1 and Model 2 was 0.801 (95% CI: 0.771-0.831) and 0.826 (95% CI: 0.796-0.857), respectively. Both models illustrated good calibration and substantial improvement in decision curve analyses than any single predictors at all threshold probabilities. Higher predicting accuracy, better calibration, and greater clinical benefit were achieved by CPCC-RC, compared with European Randomized Study for Screening of Prostate Cancer Risk Calculator and Prostate Cancer Prevention Trial Risk Calculator in predicting PCa. CPCC-RC performed well in discrimination and calibration and decision curve analysis in external validation compared

  16. Calculation of radiation dose rate arisen from radionuclide contained in building materials

    International Nuclear Information System (INIS)

    Lai Tien Thinh; Nguyen Hao Quang

    2008-01-01

    This paper presents some results that we used MCNP5 program to calculate radiation dose rate arisen from radionuclide in building materials. Since then, the limits of radionuclide content in building materials are discussed. The calculation results by MCNP are compared with those calculated by analytical method. (author)

  17. Protection against the ionizing radiations coming from external sources used in medicine: Part 1. Radiodiagnosis in medicine and dentistry

    International Nuclear Information System (INIS)

    1989-01-01

    This Venezuelan standard establishes the minimum requirements for the safety use of external sources of radiations in medical and dentistry radiodiagnosis. As a matter of fact, radiations produce noxious biological effects as: cancer, genetic damages, cataract and others. Those effects can be either avoided or limited, if we dose the exposure of radiation. The use of X-rays for diagnosis causes a massive exposure of population, that can be corrected by means of the application of rules settled down in this standard

  18. Calculated dependence of FePt damping on external field magnitude and direction

    Directory of Open Access Journals (Sweden)

    N. A. Natekar

    2017-05-01

    Full Text Available Near the Curie temperature (Tc, magnetic parameters including magnetization, anisotropy, and damping depend strongly on both temperature and length scale. This manifestation of renormalization theory is most readily seen in the case of magnetization where the magnitude of the atomic spin is largely unaffected by temperature, but the bulk magnetization vanishes at Tc. It has been previously argued that the Landau-Lifshitz-Gilbert damping parameter alpha exhibits a similar effect owing to its dependence on both atomic effects and magnon-magnon scattering, the latter having a strong length dependence. Here, we calculate, using an anisotropic exchange description of L10 FePt (Tc = 705 K, the damping (and other magnetic properties dependence on temperature for FePt at length scales around 1.0 nm as appropriate for high temperature micromagnetic simulation. While the damping reduces as the applied field along the easy direction increases, it tends to increase as the field direction is changed to in-plane. The renormalized parameters are also calculated for higher and lower Tc (770K and 630K by invoking the linear relationship between the exchange stiffness parameter and Curie temperature. This corresponds to doped and/or non-stoichiometric FePt and allows better understanding of the effects of varying anisotropy to exchange ratio.

  19. Workplace monitoring of mixed neutron-photon radiation fields and its contribution to external dosimetry

    International Nuclear Information System (INIS)

    Schuhmacher, H.

    2011-01-01

    Workplace monitoring is a common procedure for determining measures for routine radiation protection in a particular working environment. For mixed radiation fields consisting of neutrons and photons, it is of increased importance because it contributes to the improved accuracy of individual monitoring. An example is the determination of field-specific correction factors, which can be applied to the readings of personal dosemeters. This paper explains the general problems associated with individual dosimetry of neutron radiation, and describes the various options for workplace monitoring. These options cover a range from the elaborate field characterisation using transport calculations or spectrometers to the simpler approach using area monitors. Examples are given for workplaces in nuclear industry, at particle accelerators and at flight altitudes. (authors)

  20. Evaluation of dose equivalent rate distribution in JCO critical accident by radiation transport calculation

    CERN Document Server

    Sakamoto, Y

    2002-01-01

    In the prevention of nuclear disaster, there needs the information on the dose equivalent rate distribution inside and outside the site, and energy spectra. The three dimensional radiation transport calculation code is a useful tool for the site specific detailed analysis with the consideration of facility structures. It is important in the prediction of individual doses in the future countermeasure that the reliability of the evaluation methods of dose equivalent rate distribution and energy spectra by using of Monte Carlo radiation transport calculation code, and the factors which influence the dose equivalent rate distribution outside the site are confirmed. The reliability of radiation transport calculation code and the influence factors of dose equivalent rate distribution were examined through the analyses of critical accident at JCO's uranium processing plant occurred on September 30, 1999. The radiation transport calculations including the burn-up calculations were done by using of the structural info...

  1. The calculation of external gamma-ray doses from airborne and deposited radionuclides in the environmental code NECTAR

    International Nuclear Information System (INIS)

    Corbett, J.O.

    1982-02-01

    A computer program has been developed for the rapid evaluation of external gamma-ray doses from airborne and deposited radionuclide mixtures. Based on a gaussian dispersion model, the program calculates the dose at any position, including points high above ground level or upwind of the source. Meteorological frequency data for wind speed, direction, atmospheric stability and rainfall are fully taken into account. The calculational model assumes that the ground surface is perfectly flat and that gamma-ray paths are entirely in air; the possible errors caused by these and other assumptions are discussed, with suggested correction factors. The program applies various criteria to determine the best approximation or numerical integration method for each target point; execution times (on an IBM 370 machine) thus vary from less than 0.01s to about 0.3s per target point for a single weather category. The program has been incorporated in the environmental release program NECTAR. (author)

  2. Calculation of external exposure during transport and disposal of radioactive waste arisen from dismantling of steam generator

    International Nuclear Information System (INIS)

    Hornacek, M.; Necas, V.

    2014-01-01

    The dismantling of large components (reactor pressure vessel, reactor internals, steam generator) represents complex of processes involving preparation, dismantling, waste treatment and conditioning, transport and final disposal. To optimise all of these activities in accordance with the ALARA principle the prediction of the exposure of workers is an essential prerequisite. The paper deals with the calculation of external exposure of workers during transport and final disposal of heat exchange tubes of steam generator used in Slovak nuclear power plant V1 in Jaslovske Bohunice. The type of waste packages, the calculation models of truck and National Radioactive Waste Repository in Mochovce are presented. The detailed methodology of radioactive waste disposal is showed and the degree of influence of time decay (0, 5 and 10 years) on the radiological conditions during transport and disposal is studied. All of the results do not exceed the limits given in Slovak and international regulatory documents. (authors)

  3. External beam radiation therapy for squamous cell carcinoma of the soft palate

    International Nuclear Information System (INIS)

    Medini, Eitan; Medini, Allen; Gapany, Markus; Levitt, Seymour H.

    1997-01-01

    Purpose: External beam radiation therapy for carcinoma of the soft palate aims to achieve loco-regional control with normal speech, nasal function, swallowing mechanism, and minimal side effects such as nasal speech and regurgitation of food into the nasopharynx. In this report we present our results of radiotherapy in the treatment of 24 patients with squamous cell carcinoma of the soft palate. Methods and Materials: A total of 24 patients with squamous cell carcinoma of the soft palate were treated at the Veterans Administration Medical Center Minneapolis, MN, between February 1977 and May 1992. Of the 24 patients 2 had T1, 19 T2, 1 T3, and 2 had T4 lesions. Nineteen patients did not have clinical nodal disease, stage (N0), 1 had N1, 2 N2, and 2 N3 disease (Table 1). All the patients were treated by 4 MeV linear accelerator. A 1.75 Gy median dose was administered per fraction to a total of 70 Gy median dose. Bilateral opposed compensated shrinking fields technique was used. Results: The 3-year disease free survival rate after external beam radiation therapy was 100% (1 out of 1), 64.7% (11 out of 17), 100% (1 out of 1), and 0%, for patients with T1, T2, T3, and T4 disease, respectively. Salvage surgery for recurrent disease was successful in 57.1% (4 out of 7 patients). The ultimate 3-year disease free survival rate for the entire group, including surgical salvage, was 81% (17 out of 21). Conclusion: Radiation therapy alone in our institution resulted in tumor control and survival rates compare favorably to previously published reports in the literature. Surgery can be reserved as salvage procedure

  4. Environmental optimisation of natural gas fired engines - calculation of health externalities

    Energy Technology Data Exchange (ETDEWEB)

    Frohn, L.M.; Becker, T.; Christensen, Jesper; Hertel, O.; Silver, J.D.; Villadsen, H. (Aarhus Univ., National Environmental Research Institute, Dept. of Atmospheric Environment, Roskilde (Denmark)); Soees Hansen, M. (Aarhus Univ., National Environmental Research Institute, Dept. of Policy Analysis, Roskilde (Denmark)); Skou Andersen, M. (European Environment Agency, Copenhagen (Denmark))

    2010-07-01

    The measured emissions of WP1 of the project has been applied as input for model calculations with the EVA model system. The DEHM model which calculates the regional scale delta-concentrations has been further developed to handle the low signal to noise ratio of the delta-concentrations related to the small sources that the gas fired engines constitute. All combinations of engine settings and locations have been run as scenarios with the EVA system, however the results have been grouped into themes to investigate changes related to location as well as changes related to engine settings. New exposure-response relations have been implemented in the system related to the chemical components nitrogen dioxide, formaldehyde, ethene and propene. The choice of high-exposure location in the calculations has unfortunately turned out to be less optimal. The location at Store Valby has previously been applied in studies with the EVA system as a high-exposure site, however in previous applications, the emission sources have been large power plants with stack heights of around 150 meters. The height of the stack of the gas fired engines is only around 30 meters, and the consequence is that the emitted components reach the surface closer to the stack, thereby giving high exposure in an area located further to the southwest, where the population density is not as high as in central Copenhagen. In general the marginal health costs (in Euro pr kg) of carbon monoxide and formaldehyde emissions are very small. The emissions of formaldehyde are also small and the resulting costs for this component is therefore very small. The emission of carbon monoxide is much larger, however the small marginal cost makes the contribution to the total costs small, also for this component. The marginal health costs of nitrogen oxides and ethene emissions show little variation with engine scenario. However the general picture is that as the NO{sub x} emissions increase (either by increasing ignition

  5. The calculation of dose from external photon exposures using reference human phantoms and Monte Carlo methods. Pt. 7. Organ doses due to parallel and environmental exposure geometries

    Energy Technology Data Exchange (ETDEWEB)

    Zankl, M. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Drexler, G. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Petoussi-Henss, N. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Saito, K. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)

    1997-03-01

    This report presents a tabulation of organ and tissue equivalent dose as well as effective dose conversion coefficients, normalised to air kerma free in air, for occupational exposures and environmental exposures of the public to external photon radiation. For occupational exposures, whole-body irradiation with idealised geometries, i.e. broad parallel beams and fully isotropic radiation incidence, is considered. The directions of incidence for the parallel beams are anterior-posterior, posterior-anterior, left lateral, right lateral and a full 360 rotation around the body`s longitudinal axis. The influence of beam divergence on the body doses is also considered as well as the dependence of effective dose on the angle of radiation incidence. Regarding exposure of the public to environmental sources, three source geometries are considered: exposure from a radioactive cloud, from ground contamination and from the natural radionuclides distributed homogeneously in the ground. The precise angular and energy distributions of the gamma rays incident on the human body were taken into account. The organ dose conversion coefficients given in this catalogue were calculated using a Monte Carlo code simulating the photon transport in mathematical models of an adult male and an adult female, respectively. Conversion coefficients are given for the equivalent dose of 23 organs and tissues as well as for effective dose and the equivalent dose of the so-called `remainder`. The organ equivalent dose conversion coefficients are given separately for the adult male and female models and - as arithmetic mean of the conversion coefficients of both - for an average adult. Fitted data of the coefficients are presented in tables; the primary raw data as resulting from the Monte Carlo calculation are shown in figures together with the fitted data. (orig.)

  6. The calculation of dose from external photon exposures using reference human phantoms and Monte Carlo methods. Pt. 7. Organ doses due to parallel and environmental exposure geometries

    International Nuclear Information System (INIS)

    Zankl, M.

    1997-03-01

    This report presents a tabulation of organ and tissue equivalent dose as well as effective dose conversion coefficients, normalised to air kerma free in air, for occupational exposures and environmental exposures of the public to external photon radiation. For occupational exposures, whole-body irradiation with idealised geometries, i.e. broad parallel beams and fully isotropic radiation incidence, is considered. The directions of incidence for the parallel beams are anterior-posterior, posterior-anterior, left lateral, right lateral and a full 360 rotation around the body's longitudinal axis. The influence of beam divergence on the body doses is also considered as well as the dependence of effective dose on the angle of radiation incidence. Regarding exposure of the public to environmental sources, three source geometries are considered: exposure from a radioactive cloud, from ground contamination and from the natural radionuclides distributed homogeneously in the ground. The precise angular and energy distributions of the gamma rays incident on the human body were taken into account. The organ dose conversion coefficients given in this catalogue were calculated using a Monte Carlo code simulating the photon transport in mathematical models of an adult male and an adult female, respectively. Conversion coefficients are given for the equivalent dose of 23 organs and tissues as well as for effective dose and the equivalent dose of the so-called 'remainder'. The organ equivalent dose conversion coefficients are given separately for the adult male and female models and - as arithmetic mean of the conversion coefficients of both - for an average adult. Fitted data of the coefficients are presented in tables; the primary raw data as resulting from the Monte Carlo calculation are shown in figures together with the fitted data. (orig.)

  7. Radiation retinopathy after external-beam irradiation: Analysis of time-dose factors

    International Nuclear Information System (INIS)

    Parsons, J.T.; Bova, F.J.; Mendenhall, W.M.

    1994-01-01

    To investigate the risk of radiation-induced retinopathy according to total radiation dose and fraction size, based on both retorspective and prospectively collected data. Between October 1964 and May 1989, 68 retinae in 64 patients received fractionated external-beam irradiation during the treatment of primary extracranial head and neck tumors. All patients had a minimum of 3 years of ophthalmologic follow-up (range, 3 to 26 years; mean, 9 years; median, 8 years). Twenty-seven eyes in 26 patients developed radiation retinopathy resulting in visual acuity of 20/200 or worse. The mean and median times to the onset of symptoms attributable to retinal ischemia were 2.8 and 2.5 years, respectively. Fourteen of the injured eyes developed rubeosis iridis and/or neovascular glaucoma. Radiation retinopathy was not observed at doses below 45 Gy, but increased steadily in incidence at doses ≥45Gy. In the range of doses between 45 and 55 Gy, there was an increased risk of injury among patients who received doses per fraction of ≥1.9Gy (p - .09). There was also a trend toward increased risk of injury among patients who received chemotherapy (two of two vs. four of ten in the 45-51 Gy range; p - .23). The lowest dose associated with retinopathy was 45 Gy delivered to a diabetic patient by twice-a-day fractionation. The data did not suggest an increased risk of radiation retinopathy with increasing age. The current study suggests the importance of total dose as well as dose per fraction, and adds support to a small body of literature suggesting that patients with diabetes mellitus or who receive chemotherapy are at increased risk of injury. A sigmoid dose-response curve is constructed from our current data and data from the literature. 36 refs., 5 figs., 4 tabs

  8. External exposure rates from terrestrial radiation at Guarapari and Meaipe in Brazil

    International Nuclear Information System (INIS)

    Fujinami, N.; Koga, T.; Morishima, H.

    2000-01-01

    Recently epidemiological and cytogenetic studies on inhabitants living in high background radiation areas have been carried out in order to examine health effects of exposure to low dose radiation. Guarapari and Meaipe are towns built on the monazite sand region along the Atlantic coast in Brazil, which is one of the widely known high background radiation areas in the world. As an initial step toward studies on health effects of high background radiation on inhabitants living in Guarapari and Meaipe, we surveyed absorbed dose rates in air in these towns with a portable NaI(Tl) scintillation detector in September 1998. Sand and soil were also sampled there so as to determine the concentrations of Th-232 and Ra-226 in them. In Guarapari and Meaipe, dose rates in the streets ranged from 0.1 to 0.4 μ Gy/h except for a few places such as near the Areia Preta beach and Meaipe beach. Dose rates inside houses were lower than 0.2 μ Gy/h except that two houses attained a dose rate of 0.4 μ Gy/h. Our effective dose rate from external terrestrial irradiation (outdoors and indoors) was 0.17 μ Sv/h on the average, during the period of our three day stay in Guarapari and Meaipe. From comparison of our present values with those observed in the 1960s, which were cited in UNSCEAR reports, it is indicated that dose rate levels have decreased clearly in downtown, while the levels have scarcely changed in beaches and unpaved beach streets which have not been developed yet. This fact suggests that the natural radiation environment of Guarapari and Meaipe has varied with urbanization which brought paved streets, and changes in the structure and building materials of houses. A detailed survey is necessary in order to evaluate present absorbed dose rates in air in this area. (author)

  9. Evaluation of Delivery Costs for External Beam Radiation Therapy and Brachytherapy for Locally Advanced Cervical Cancer Using Time-Driven Activity-Based Costing.

    Science.gov (United States)

    Bauer-Nilsen, Kristine; Hill, Colin; Trifiletti, Daniel M; Libby, Bruce; Lash, Donna H; Lain, Melody; Christodoulou, Deborah; Hodge, Constance; Showalter, Timothy N

    2018-01-01

    To evaluate the delivery costs, using time-driven activity-based costing, and reimbursement for definitive radiation therapy for locally advanced cervical cancer. Process maps were created to represent each step of the radiation treatment process and included personnel, equipment, and consumable supplies used to deliver care. Personnel were interviewed to estimate time involved to deliver care. Salary data, equipment purchasing information, and facilities costs were also obtained. We defined the capacity cost rate (CCR) for each resource and then calculated the total cost of patient care according to CCR and time for each resource. Costs were compared with 2016 Medicare reimbursement and relative value units (RVUs). The total cost of radiation therapy for cervical cancer was $12,861.68, with personnel costs constituting 49.8%. Brachytherapy cost $8610.68 (66.9% of total) and consumed 423 minutes of attending radiation oncologist time (80.0% of total). External beam radiation therapy cost $4055.01 (31.5% of total). Personnel costs were higher for brachytherapy than for the sum of simulation and external beam radiation therapy delivery ($4798.73 vs $1404.72). A full radiation therapy course provides radiation oncologists 149.77 RVUs with intensity modulated radiation therapy or 135.90 RVUs with 3-dimensional conformal radiation therapy, with total reimbursement of $23,321.71 and $16,071.90, respectively. Attending time per RVU is approximately 4-fold higher for brachytherapy (5.68 minutes) than 3-dimensional conformal radiation therapy (1.63 minutes) or intensity modulated radiation therapy (1.32 minutes). Time-driven activity-based costing was used to calculate the total cost of definitive radiation therapy for cervical cancer, revealing that brachytherapy delivery and personnel resources constituted the majority of costs. However, current reimbursement policy does not reflect the increased attending physician effort and delivery costs of brachytherapy. We

  10. The calculation of dose from external photon exposures using reference human phantoms and Monte Carlo methods. Pt. 4

    International Nuclear Information System (INIS)

    Williams, G.; Zankl, M.; Drexler, G.

    1984-12-01

    This report considers the contribution from scattered radiation to the dose to organs and tissues which lie outside the useful therapy beams. The results presented are the product of Monte Carlo studies used to determine the tissue doses due to internal scattering of the useful beams only. General cases are calculated in which central target volumes in the trunk are treated with 10 x 14 cm 2 and 14 x 14 cm 2 fields from 200 kV, Co-60, 8 MV and 25 MV therapy equipment. Target volumes in the neck are considered to be treated with 5 x 5 cm 2 fields. Different treatment plans are calculated including rotational therapy. Also two specific cases are more fully analysed, namely for Ankylosing Spondylitis and central abdomen malignant disease in the region of the head of the pancreas. The calculated organ doses are presented in tables as a percentage of the target volume dose. (orig.)

  11. Radiation calculations using LAHET/MCNP/CINDER90

    International Nuclear Information System (INIS)

    Waters, L.

    1994-01-01

    The LAHET monte carlo code system has recently been expanded to include high energy hadronic interactions via the FLUKA code, while retaining the original Los Alamos versions of HETC and ISABEL at lower energies. Electrons and photons are transported with EGS4 or ITS, while the MCNP coupled neutron/photon monte carlo code provides analysis of neutrons with kinetic energies less than 20 MeV. An interface with the CINDER activation code is now in common use. Various other changes have been made to facilitate analysis of high energy accelerator radiation environments and experimental physics apparatus, such as those found at SSC and RHIC. Current code developments and applications are reviewed

  12. Calculation of radiation exposure in diagnostic radiology. Method and surveys

    International Nuclear Information System (INIS)

    Duvauferrier, R.; Ramee, A.; Ezzeldin, K.; Guibert, J.L.

    1984-01-01

    A computerized method for evaluating the radiation exposure of the main target organs during various diagnostic radiologic procedures is described. This technique was used for educational purposes: study of exposure variations according to the technical modalities of a given procedure, and study of exposure variations according to various technical protocols (IVU, EGD barium study, etc.). This method was also used for studying exposure of patients during hospitalization in the Rennes Regional Hospital Center (France) in 1982, according to departments (urology, neurology, etc.). This method and results of these three studies are discussed [fr

  13. Simplified models for radiational losses calculating a tokamak plasma

    International Nuclear Information System (INIS)

    Arutiunov, A.B.; Krasheninnikov, S.I.; Prokhorov, D.Yu.

    1990-01-01

    To determine the magnitudes and profiles of radiational losses in a Tokamak plasma, particularly for high plasma densities, when formation of MARFE or detached-plasma takes place, it is necessary to know impurity distribution over the ionization states. Equations describing time evolution of this distribution are rather cumbersome, besides that, transport coefficients as well as rate constants of the processes involving complex ions are known nowadays with high degree of uncertainty, thus it is believed necessary to develop simplified, half-analytical models describing time evolution of the impurities analysis of physical processes taking place in a Tokamak plasma on the base of the experimental data. (author) 6 refs., 2 figs

  14. Occupational exposure from external radiation used in medical practices in Pakistan by film badge dosimetry

    International Nuclear Information System (INIS)

    Jabeen, A.; Munir, M.; Khalil, A.; Masood, M.; Akhter, P.

    2010-01-01

    Occupational exposure data of workers due to external sources of radiation in various medical practices such as nuclear medicine (NM), radiotherapy and diagnostic radiology (DR) in Pakistan were collected and analysed. Whole-body doses of workers were measured by film badge dosimetry technique during 2003-2007. Annual average effective dose in NM, radio-therapy and DR varied in the range of 1.39-1.80, 1.05-1.45 and 1.22-1.71 mSv, respectively, during 2003-2007. These values are quite low and well below the annual limit of 20 mSv averaged over a period of 5 consecutive years. Nobody received the radiation dose >50 mSv in any single year over a period of 5 consecutive years; therefore, no overexposure case has been detected. Decreasing trend of annual average dose values in aforementioned categories of work during 2003-2007 indicates the improvement of radiation protection status in medical field in Pakistan. (authors)

  15. Environmental external gamma radiation isodose map of Kinta and Batang Padang Districts, Perak

    International Nuclear Information System (INIS)

    Ismail, B.; Monawarah, N.M.Y.; Hng, P.W.; Sharifah Mastura, S.A

    2005-01-01

    The background radiation levels of any area, including those related to having deposit of NORM is important to be mapped out before being developed in order to assess their for potential radiological risk. A study was carried out map the environmental external gammas radiation dose rates in Kinta and Batang Padang Districts, Perak. The interpolation method in GIS was used to produce an isodose map based on prediction made from 13 different geological structure soil type combinations. Actual field measurements were carried using Sodium Iodine detectors. A predicted isodose map was plotted based on 5 dose rate classes, ranging from 0.16-0.57 Sv hr -1 . The area dose rates was increased to 5.00 Sv hr -1 once the dose rates contributed artificially by among plants to the study area was considered. Results also showed that the geosoil combination of steep land and acid intrusive rock areas radiates the highest dose rate levels (90.31 %) and most of these areas are in areas covered by hilly mountain. (Author)

  16. A model for calculating hourly global solar radiation from satellite data in the tropics

    International Nuclear Information System (INIS)

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J.

    2009-01-01

    A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country.

  17. A model for calculating hourly global solar radiation from satellite data in the tropics

    Energy Technology Data Exchange (ETDEWEB)

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J. [Solar Energy Research Laboratory, Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom 73000 (Thailand)

    2009-09-15

    A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country. (author)

  18. Measurements and theoretical calculations of diffused radiation and atmosphere lucidity

    International Nuclear Information System (INIS)

    Pelece, I.; Iljins, U.; Ziemelis, I.

    2009-01-01

    Align with other environment friendly renewable energy sources solar energy is widely used in the world. Also in Latvia solar collectors are used. However, in Latvia because of its geographical and climatic conditions there are some specific features in comparison with traditional solar energy using countries. These features lead to the necessity to pay more attention to diffused irradiance. Another factor affecting the received irradiance of any surface is lucidity of atmosphere. This factor has not been studied in Latvia yet. This article deals with evaluation of diffused irradiance, and also of lucidity of atmosphere. The diffused irradiance can be measured directly or as a difference between the global irradiance and the beam one. The lucidity of atmosphere can be calculated from the measurements of both global and beam irradiance, if the height of the sun is known. Therefore, measurements of both global and beam irradiance have been carried out, and the diffused irradiance calculated as a difference between the global irradiance and the beam one. For measuring of the global irradiance the dome solarimeter has been used. For measuring of the direct irradiance tracking to sun pirheliometer has been used. The measurements were performed in Riga from October 2008 till March 2009. The measurements were executed automatically after every 5 minutes. The obtained results have been analyzed taking into account also the data on nebulosity from the State agency Latvian Environment, Geology and Meteorology Agency. Also efforts to calculate theoretically the diffused irradiance from the height of the sun and the data of the nebulosity have been done. These calculated values have been compared with the measured ones. Good accordance is obtained. (author)

  19. Sample size calculation to externally validate scoring systems based on logistic regression models.

    Directory of Open Access Journals (Sweden)

    Antonio Palazón-Bru

    Full Text Available A sample size containing at least 100 events and 100 non-events has been suggested to validate a predictive model, regardless of the model being validated and that certain factors can influence calibration of the predictive model (discrimination, parameterization and incidence. Scoring systems based on binary logistic regression models are a specific type of predictive model.The aim of this study was to develop an algorithm to determine the sample size for validating a scoring system based on a binary logistic regression model and to apply it to a case study.The algorithm was based on bootstrap samples in which the area under the ROC curve, the observed event probabilities through smooth curves, and a measure to determine the lack of calibration (estimated calibration index were calculated. To illustrate its use for interested researchers, the algorithm was applied to a scoring system, based on a binary logistic regression model, to determine mortality in intensive care units.In the case study provided, the algorithm obtained a sample size with 69 events, which is lower than the value suggested in the literature.An algorithm is provided for finding the appropriate sample size to validate scoring systems based on binary logistic regression models. This could be applied to determine the sample size in other similar cases.

  20. Comparative study of different methods used in assessment of population exposure to external environmental radiation

    International Nuclear Information System (INIS)

    Niewiadomski, T.

    1979-08-01

    Doses received by individuals and population from terrestial radiation sources were estimated using three approaches, 1) measurements of dose rates, 2) calculations on the basis of spectrometric analysis of the soil or local radiation field and 3) integrating dosimeters. The 1st approach was carried out by means of pressurised ionization chambers, scintillation counters or GM counters properly calibrated, and also by supplying individuals with dosimetric or radiometric instruments. The data for calculation assessment was based on measurements of dose rates both outdoors and indoors and often taken from spectrometric analysis of natural radionuclide. Several equations and calculation factors have been derived and computer programs developed for calculating the concentration of radionuclides in question and for estimating dose rates in π or 2π geometries. Integrating measurements were carried out using TL dosimeters. To assess the reliability of the methods, comparative measurements were carried out at statistically representative number of locations using a wide choice of techniques. The detailed methods used and the equipment are described in the research programme as well as the results of the measurements. The most reliable results are these obtained when measurements are carried out over a long period of time, e.g. one year

  1. Assessment of population external irradiation doses with consideration of Rospotrebnadzor bodies equipment for monitoring of photon radiation dose

    Directory of Open Access Journals (Sweden)

    I. P. Stamat

    2016-01-01

    Full Text Available This paper provides review of equipment and methodology for measurement of photon radiation dose; analysis of possible reasons for considerable deviation between the Russian Federation population annual effective external irradiation doses and the relevant average global value. Data on Rospotrebnadzor bodies dosimetry equipment used for measurement of gamma radiation dose are collected and systematized. Over 60 kinds of dosimeters are used for monitoring of population external irradiation doses. Most of dosimeters used in the country have gas-discharge detectors (Geiger-Mueller counters, minor biochemical annunciators, etc. which have higher total values of own background level and of space radiation response than the modern dosimeters with scintillation detectors. This feature of dosimeters is apparently one of most plausible reasons of a bit overstating assessment of population external irradiation doses. The options for specification of population external irradiation doses assessment are: correction of gamma radiation dose measurement results with consideration of dosimeters own background level and space radiation response, introduction of more up-to-date dosimeters with scintillation detectors, etc. The most promising direction of research in verification of population external irradiation doses assessment is account of dosimetry equipment.

  2. Assessment of effectiveness of geologic isolation systems. ARRRG and FOOD: computer programs for calculating radiation dose to man from radionuclides in the environment

    International Nuclear Information System (INIS)

    Napier, B.A.; Roswell, R.L.; Kennedy, W.E. Jr.; Strenge, D.L.

    1980-06-01

    The computer programs ARRRG and FOOD were written to facilitate the calculation of internal radiation doses to man from the radionuclides in the environment and external radiation doses from radionuclides in the environment. Using ARRRG, radiation doses to man may be calculated for radionuclides released to bodies of water from which people might obtain fish, other aquatic foods, or drinking water, and in which they might fish, swim or boat. With the FOOD program, radiation doses to man may be calculated from deposition on farm or garden soil and crops during either an atmospheric or water release of radionuclides. Deposition may be either directly from the air or from irrigation water. Fifteen crop or animal product pathways may be chosen. ARRAG and FOOD doses may be calculated for either a maximum-exposed individual or for a population group. Doses calculated are a one-year dose and a committed dose from one year of exposure. The exposure is usually considered as chronic; however, equations are included to calculate dose and dose commitment from acute (one-time) exposure. The equations for calculating internal dose and dose commitment are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and Maximum Permissible Concentration (MPC) of each radionuclide. The radiation doses from external exposure to contaminated farm fields or shorelines are calculated assuming an infinite flat plane source of radionuclides. A factor of two is included for surface roughness. A modifying factor to compensate for finite extent is included in the shoreline calculations

  3. Assessment of effectiveness of geologic isolation systems. ARRRG and FOOD: computer programs for calculating radiation dose to man from radionuclides in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.; Roswell, R.L.; Kennedy, W.E. Jr.; Strenge, D.L.

    1980-06-01

    The computer programs ARRRG and FOOD were written to facilitate the calculation of internal radiation doses to man from the radionuclides in the environment and external radiation doses from radionuclides in the environment. Using ARRRG, radiation doses to man may be calculated for radionuclides released to bodies of water from which people might obtain fish, other aquatic foods, or drinking water, and in which they might fish, swim or boat. With the FOOD program, radiation doses to man may be calculated from deposition on farm or garden soil and crops during either an atmospheric or water release of radionuclides. Deposition may be either directly from the air or from irrigation water. Fifteen crop or animal product pathways may be chosen. ARRAG and FOOD doses may be calculated for either a maximum-exposed individual or for a population group. Doses calculated are a one-year dose and a committed dose from one year of exposure. The exposure is usually considered as chronic; however, equations are included to calculate dose and dose commitment from acute (one-time) exposure. The equations for calculating internal dose and dose commitment are derived from those given by the International Commission on Radiological Protection (ICRP) for body burdens and Maximum Permissible Concentration (MPC) of each radionuclide. The radiation doses from external exposure to contaminated farm fields or shorelines are calculated assuming an infinite flat plane source of radionuclides. A factor of two is included for surface roughness. A modifying factor to compensate for finite extent is included in the shoreline calculations.

  4. Uncertainties in personal dosimetry for external radiation: A Monte Carlo approach

    International Nuclear Information System (INIS)

    Van Dijk, J. W. E.

    2006-01-01

    This paper explores the possibilities of numerical methods for uncertainty analysis of personal dosimetry systems. Using a numerical method based on Monte Carlo sampling the probability density function (PDF) of the dose measured using a personal dosemeter can be calculated using type-test measurements. From this PDF the combined standard uncertainty in the measurements with the dosemeter and the confidence interval can be calculated. The method calculates the output PDF directly from the PDFs of the inputs of the system such as the spectral distribution of the radiation and distributions of detector parameters like sensitivity and zero signal. The method can be used not only in its own right but also for validating other methods because it is not limited by restrictions that apply to using the Law of Propagation of Uncertainty and the Central Limit Theorem. The use of the method is demonstrated using the type-test data of the NRG-TLD. (authors)

  5. Time step size selection for radiation diffusion calculations

    International Nuclear Information System (INIS)

    Rider, W.J.; Knoll, D.A.

    1999-01-01

    The purpose of this note is to describe a time step control technique as applied to radiation diffusion. Standard practice only provides a heuristic criteria related to the relative change in the dependent variables. The authors propose an alternative based on relatively simple physical principles. This time step control applies to methods of solution that are unconditionally stable and converges nonlinearities within a time step in the governing equations. Commonly, nonlinearities in the governing equations are evaluated using existing (old time) data. The authors refer to this as the semi-implicit (SI) method. When a method converges nonlinearities within a time step, the entire governing equation including all nonlinearities is self-consistently evaluated using advance time data (with appropriate time centering for accuracy)

  6. Long-term follow-up observation of patients with chronic radiation sickness due to external irradiation treated with thymopeptide

    International Nuclear Information System (INIS)

    Gao Shenyong; Sun Wenji; Zhang Aizhen; Ye Anfang

    1998-01-01

    Objective: To provide the clinical data and prognosis judgement, the authors observed the results and progression of 11 cases of chronic radiation sickness due to external irradiation treated with thymopeptide. Methods: The clinical symptoms, hematopoiesis, T lymphocyte percentage and chromosome aberration rate were used as the judgement indexes for recovery from the chronic radiation sickness. Results: Thymopeptide treatment greatly improved the neurasthenic syndrome and increased the T lymphocyte percentage (P 0.05), and improvement of neurasthenic syndrome occurred 3.5 years after they left radiation work or diminished the exposure level. 5 to 8 years after, bone marrow hematopoiesis also restored to the normal level. However, the chromosome aberration rate restored to the normal level 10 years after. Conclusion: According to the judgement criteria, the chronic radiation sickness due to external radiation exposure can recover and thymopeptide is a helpful and simple means to treat it

  7. Deterministic calculations of radiation doses from brachytherapy seeds

    International Nuclear Information System (INIS)

    Reis, Sergio Carneiro dos; Vasconcelos, Vanderley de; Santos, Ana Maria Matildes dos

    2009-01-01

    Brachytherapy is used for treating certain types of cancer by inserting radioactive sources into tumours. CDTN/CNEN is developing brachytherapy seeds to be used mainly in prostate cancer treatment. Dose calculations play a very significant role in the characterization of the developed seeds. The current state-of-the-art of computation dosimetry relies on Monte Carlo methods using, for instance, MCNP codes. However, deterministic calculations have some advantages, as, for example, short computer time to find solutions. This paper presents a software developed to calculate doses in a two-dimensional space surrounding the seed, using a deterministic algorithm. The analysed seeds consist of capsules similar to IMC6711 (OncoSeed), that are commercially available. The exposure rates and absorbed doses are computed using the Sievert integral and the Meisberger third order polynomial, respectively. The software also allows the isodose visualization at the surface plan. The user can choose between four different radionuclides ( 192 Ir, 198 Au, 137 Cs and 60 Co). He also have to enter as input data: the exposure rate constant; the source activity; the active length of the source; the number of segments in which the source will be divided; the total source length; the source diameter; and the actual and effective source thickness. The computed results were benchmarked against results from literature and developed software will be used to support the characterization process of the source that is being developed at CDTN. The software was implemented using Borland Delphi in Windows environment and is an alternative to Monte Carlo based codes. (author)

  8. The calculation of dose from external photon exposures using reference human phantoms and Monte Carlo methods. Pt. 6

    International Nuclear Information System (INIS)

    Zankl, M.; Panzer, W.; Drexler, G.

    1991-11-01

    Computed tomography (CT) is a technique which offers a high diagnostic capability; however, the dose to the patient is high compared to conventional radiography. This report provides a catalogue of organ doses resulting from CT examinations. The organ doses were calculated for the type of CT scanners most commonly used in the FRG and for three different radiation qualities. For the dose calculations, the patients were represented by the adult mathematical phantoms Adam and Eva. The radiation transport in the body was simulated using a Monte Carlo method. The doses were calculated as conversion factors of mean organ doses per air kerma free in air on the axis of rotation. Mean organ dose conversion factors are given per organ and per single CT slice of 1 cm width. The mean dose to an organ resulting from a particular CT examination can be estimated by summing up the contribution to the organ dose from each relevant slice. In order to facilitate the selection of the appropriate slices, a table is given which relates the mathematical phantoms' coordinates to certain anatomical landmarks in the human body. (orig.)

  9. Increasing Use of Dose-Escalated External Beam Radiation Therapy for Men With Nonmetastatic Prostate Cancer

    International Nuclear Information System (INIS)

    Swisher-McClure, Samuel; Mitra, Nandita; Woo, Kaitlin; Smaldone, Marc; Uzzo, Robert; Bekelman, Justin E.

    2014-01-01

    Purpose: To examine recent practice patterns, using a large national cancer registry, to understand the extent to which dose-escalated external beam radiation therapy (EBRT) has been incorporated into routine clinical practice for men with prostate cancer. Methods and Materials: We conducted a retrospective observational cohort study using the National Cancer Data Base, a nationwide oncology outcomes database in the United States. We identified 98,755 men diagnosed with nonmetastatic prostate cancer between 2006 and 2011 who received definitive EBRT and classified patients into National Comprehensive Cancer Network (NCCN) risk groups. We defined dose-escalated EBRT as total prescribed dose of ≥75.6 Gy. Using multivariable logistic regression, we examined the association of patient, clinical, and demographic characteristics with the use of dose-escalated EBRT. Results: Overall, 81.6% of men received dose-escalated EBRT during the study period. The use of dose-escalated EBRT did not vary substantially by NCCN risk group. Use of dose-escalated EBRT increased from 70.7% of patients receiving treatment in 2006 to 89.8% of patients receiving treatment in 2011. On multivariable analysis, year of diagnosis and use of intensity modulated radiation therapy were significantly associated with receipt of dose-escalated EBRT. Conclusions: Our study results indicate that dose-escalated EBRT has been widely adopted by radiation oncologists treating prostate cancer in the United States. The proportion of patients receiving dose-escalated EBRT increased nearly 20% between 2006 and 2011. We observed high utilization rates of dose-escalated EBRT within all disease risk groups. Adoption of intensity modulated radiation therapy was strongly associated with use of dose-escalated treatment

  10. Advanced nuclear data for radiation-damage calculations

    International Nuclear Information System (INIS)

    MacFarlane, R.E.; Foster, D.G. Jr.

    1983-01-01

    Accurate calculations of atomic displacement damage in materials exposed to neutrons require detailed spectra for primary recoil nuclei. Such data are not available from direct experimental measurements. Moreover, they cannot always be computed accurately starting from evaluated nuclear data libraries such as ENDF/B-V that were developed primarily for neutron transport applications, because these libraries lack detailed energy-and-angle distributions for outgoing charged particles. Fortunately, a new generation of nuclear model codes is now available that can be used to fill in the missing spectra. One example is the preequilibrium statistical-model code GNASH. For heating and damage applications, a supplementary code called RECOIL has been developed. RECOIL uses detailed reaction data from GNASH, together with angular distributions based on Kalbach-Mann systematics to compute the energy and angle distributions of recoil nuclei. The energy-angle distributions for recoil nuclei and outgoing particles are written out in the new ENDF/B File 6 format. The result is a complete set of nuclear data that can be used to calculate displacement-energy production, heat production, gas production, transmutation, and activation. Sample results for iron are given and compared to the results of conventional damage models such as those used in NJOY

  11. Radiation dose to laterally transposed ovaries during external beam radiotherapy for cervical cancer

    International Nuclear Information System (INIS)

    Mazonakis, Michael; Damilakis, John; Varveris, Haris; Gourtsoyiannis, Nicholas

    2006-01-01

    The purpose of this study was to estimate the radiation dose to laterally transposed ovaries from external beam radiotherapy for cervical cancer. Dose measurements were performed in a modified humanoid phantom using a 6 MV photon beam. The dependence of the ovarian dose upon the field size, the distance from the primary irradiation field and the presence of wedges or gonadal shielding was determined. For a tumor dose of 45 Gy, ovarian dose was 0.88-8.51 Gy depending on the field size employed and the location of the transposed ovary in respect to the treatment field. Positioning of 7 cm thick shielding reduced the dose to ovary by less than 19%. The use of wedges increased the ovarian dose by a factor up to 1.5. Accurate radiographic localization of the ovaries allows the use of the presented dosimetric results to obtain a reasonable prediction of the ovarian dose

  12. Summary of recorded external radiation doses for Hanford workers 1944--1989

    International Nuclear Information System (INIS)

    Buschbom, R.L.; Gilbert, E.S.

    1993-10-01

    This report summarizes recorded external radiation doses for the years 1944 through 1989 received by operations workers who were included in the Hanford Mortality Study. This study population includes all operations workers who were initially employed at the Hanford site from 1944 through 1978. Descriptive summaries are provided for both annual and cumulative whole body penetrating doses. Although the main emphasis of the report is on recorded whole body penetrating dose, summary tables are included for the components of whole body penetrating dose, non-penetrating dose, and extremity dose. Summaries are provided for the entire study population and for subgroups of the population defined by sex, age, number of years since first monitoring, and socioeconomic groups

  13. Measurement and calculation of radiation fields of the Sandia irradiator for dried sewage solids

    International Nuclear Information System (INIS)

    Morris, M.E.

    1981-03-01

    The radiation field of the Sandia Irradiator for Dried Sewage Solids was measured. The results of the measurement are given in this report. In addition, theoretical calculations of the fields are given and then compared with the measured values. Elementary models of the radiation source geometry and irradiated product are found to be adequate and thus allow us to duplicate (through calculation) the important features of the measured fields

  14. Automation of POST Cases via External Optimizer and "Artificial p2" Calculation

    Science.gov (United States)

    Dees, Patrick D.; Zwack, Mathew R.

    2017-01-01

    optimizer functions like any other gradient-based optimizer. It has a specified variable to optimize whose value is represented as optval, a set of dependent constraints to meet with associated forms and tolerances whose value is represented as p2, and a set of independent variables known as the u-vector to modify in pursuit of optimality. Each of these quantities are calculated or manipulated at a certain phase within the trajectory. The optimizer is further constrained by the requirement that the input u-vector must result in a trajectory which proceeds through each of the prescribed events in the input file. For example, if the input u-vector causes the vehicle to crash before it can achieve the orbital parameters required for a parking orbit, then the run will fail without engaging the optimizer, and a p2 value of exactly zero is returned. This poses a problem, as this "non-connecting" region of the u-vector space is far larger than the "connecting" region which returns a non-zero value of p2 and can be worked on by the internal optimizer. Finding this connecting region and more specifically the global optimum within this region has traditionally required the use of an expert analyst.

  15. Hyperfractionated external radiation therapy in stage IIIB carcinoma of uterine cervix: a prospective pilot study

    International Nuclear Information System (INIS)

    Faria, Sergio L.; Ferrigno, Robson

    1997-01-01

    Purpose: Brazil has one of the highest incidence of carcinoma of the cervix in the world. Half of the patients have advanced stages at the diagnosis. Due to this large number of patients we decided to conduct a prospective pilot study to investigate the tolerance to and survival rate with hyperfractionated external radiotherapy only in patients with Stage IIIB carcinoma of the uterine cervix. Methods and Materials: Between January 1991 and December 1993, 23 patients underwent hyperfractionated external beam radiotherapy without brachytherapy. All cases were biopsy proven squamous cell carcinoma of cervix clinically Staged as IIIB (FIGO). Hyperfractionation (HFX) was given with 1.2 Gy doses, twice daily at 6-h interval, 5 days/week, to the whole pelvis up to 72 Gy within 30 working days. Complications were evaluated by an adaptation of the RTOG Radiation Morbidity Scoring Table graded as 1 = none/mild; 2 = moderate, and 3 = severe. Results: Follow-up ranged from 27 to 50 months (median 40 months) on the 9 to 23 living patients at the time of the analysis in December 1995. There was no severe acute toxicity, but moderate acute reaction was high: 74%. The commonest site of complication was the intestine where severe late toxicity occurred in 2 of 23 (9%). Overall survival rate at 27 months was 48% and at 40 months was 43%. Discussion: There is little information in literature about HFX in carcinoma of the cervix. This is the third published study about it and the one that gave the highest total dose with external HFX of 60 x 1.2 Gy = 72 Gy. Theoretically, through the linear quadratic formula this schedule of HFX would be equivalent to 30 x 2 Gy = 60 Gy of standard fractionation, both treatments given in 30 working days. HFX schedules must be tested to establish their safety. Present results suggest being possible to further increase the total dose in the pelvis with hyperfractionated irradiation

  16. External radiation exposure and radiotoxicity considerations in plutonium/uranium mixed-oxide fuel fabrication

    International Nuclear Information System (INIS)

    Williams, R.A.; Crosby, E.H.

    1974-01-01

    Nuclear-reactor-produced plutonium emits significant electromagnetic and neutron radiations. In addition, because of its high specific alpha activity and its tendency to deposit in the lung and the soft tissues of the bone, plutonium presents a significant radiotoxicity hazard. Shielding, containment, and dosimetry techniques practiced at the Nuclear Materials and Equipment Corporation (NUMEC) have resulted in exemplary annual safety report statistics relevant to non-remote-handling plutonium operations. Whereas a few employees exceeded the NUMEC external exposure action level, no employee exceeded the Regulatory maximum permissible external exposure. In addition, a few employees were observed to have a lung burden in excess of the minimum sensitivity of an in vivo counting system, and one employee was observed by in vivo counting to have a lung burden in excess of the maximum permissible for a brief period. No employee was observed to have a body burden as indicated by a positive quarterly urinalysis result. Further, there were no serious incidents at the facility requiring immediate Regulatory notification, and there were no moderate incidents at the facility requiring 24-h Regulatory notification. However, there were a few reportable incidents at the facility requiring 30-day Regulatory notification, and there were a few minor incidents at the facility requiring the preparation of a NUMEC Incident Report. Details of this safety record are presented along with the health physics techniques that have contributed to the results

  17. The value of external beam radiation in pathologic node positive prostate cancer: a multivariate analysis

    International Nuclear Information System (INIS)

    Morris, Astrid D.; Zietman, Anthony L.; Althausen, Alex F.; Heney, Niall M.; Kaufman, Donald S.; Shipley, William U.

    1997-01-01

    Purpose: The goal of this study was to evaluate the effect of local/regional treatment, particularly external beam radiation alone versus radical prostatectomy and radiation therapy in patients with pathologic node positive prostate cancer on survival. The effect of delayed vs. immediate endocrine therapy on patients treated with radiation alone was also examined. Methods: Medical records of all 116 patients who received their initial treatment at the Massachusetts General Hospital between 1980 and 1996 for adenocarcinoma of the prostate with pathologic confirmed nodal metastasis and no distant disease were reviewed. The mean follow up was 5.5 years. Disease specific survival, time to PSA failure on endocrine therapy, and time to first intervention were evaluated. PSA failure was defined as two consecutive post-nadir rises following the first use of endocrine therapy. Intervention was defined as any surgical or radiotherapeutic procedure required for relief of symptoms related to local/regional recurrence. Survival comparisons were made between any local/regional treatment vs. none, radiation therapy alone vs. prostatectomy with radiation therapy, and immediate vs. delayed endocrine therapy. The effect of the different treatment options on survival were compared using multivariate Cox proportional hazard models to simultaneously adjust for patient and tumor characteristics (tumor stage, Gleason grade, number of positive nodes) that might influence survival. Results: The combined patient population had a 5 year disease specific survival of 74% and a 10 year disease specific survival of 48%. The comparison groups for local/regional treatment had the following adjusted outcomes. In a subgroup analysis of patients with clinical T1-T2 and clinical T3-T4 disease, local/regional treatment continued to confer a disease specific survival advantage over no local regional treatment in both subgroups (p=0.05 and p=0.02, respectively). PSA failure on endocrine therapy was

  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. Use of a concise prescription for specifying absolute dose distribution in external beam radiation therapy

    International Nuclear Information System (INIS)

    Viggers, D.A.; Shalev, S.

    1989-01-01

    Radiation therapy dose distributions are usually calculated relative to some normalization point to which a prescribed dose in grays is to be delivered. Often the radiation therapist requests that the prescribed dose be delivered to some other point(s), such as the 90% isodose. Therefore the prescribed dose is not well defined. Furthermore, this procedure leaves the shape of the dose distribution unspecified. The authors have used a dose prescription specifying the volumes of target and nontarget tissue that must lie within dose limits stated in grays. These dose-volume limits determine the magnitude and shape of the dose distribution. The prescription is well defined while allowing the absolute dose at a chosen point to be adjusted so that the dose distribution satisfies the prescription

  20. Comparison and application study on cosmic radiation dose calculation received by air crew

    International Nuclear Information System (INIS)

    Zhou Qiang; Xu Cuihua; Ren Tianshan; Li Wenhong; Zhang Jing; Lu Xu

    2009-01-01

    Objective: To facilitate evaluation on Cosmic radiation dose received by flight crew by developing a convenient and effective measuring method. Methods: In comparison with several commonly used evaluating methods, this research employs CARI-6 software issued by FAA (Federal Aviation Administration) to measure Cosmic radiation dose for flight crew members exposed to. Results: Compared with other methods, CARI-6 is capable of providing reliable calculating results on radiation dose and applicable to all flight crew of different airlines. Conclusion: Cosmic radiation received by flight crew is on the list of occupational radiation. For a smooth running of Standards for controlling exposure to cosmic radiation of air crew, CARI software may be a widely applied tool in radiation close estimation of for flight crew. (authors)

  1. Radiation by the numbers: developing an on-line Canadian radiation dose calculator as a public engagement and education tool

    Energy Technology Data Exchange (ETDEWEB)

    Dalzell, M.T.J. [Sylvia Fedoruk Canadian Centre for Nuclear Innovation, Saskatoon, Saskatchewan (Canada)

    2016-06-15

    Concerns arising from misunderstandings about radiation are often cited as a main reason for public antipathy towards nuclear development and impede decision-making by governments and individuals. A lack of information about everyday sources of radiation exposure that is accessible, relatable and factual contributes to the problem. As part of its efforts to be a fact-based source of information on nuclear issues, the Sylvia Fedoruk Canadian Centre for Nuclear Innovation has developed an on-line Canadian Radiation Dose Calculator as a tool to provide context about common sources of radiation. This paper discusses the development of the calculator and describes how the Fedoruk Centre is using it and other tools to support public engagement on nuclear topics. (author)

  2. Modeling of beams in a treatment planning system for external radiation with the help of external tool

    International Nuclear Information System (INIS)

    Suero Rodrigo, M. A.; Marques Fraguela, E.

    2011-01-01

    In this paper we attempt a statistical analysis as directed Protocol Control Systems Quality Planning Radiation Therapy published by the Spanish Society of Medical Physics. Also performed an analysis with the parameter gamma (Low et al.), Which is represented on the graph, allowing an overview of the goodness of fit intuitively.

  3. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N. [National Radiation Protection Dept. Atomic Energy Organization (Iran, Islamic Republic of); Sohrabi, M. [Intenatinal atomic Energy Agency, Vienna (Austria)

    2006-07-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 {mu}R/h, and outdoor environments of different cities is 7.9-20.6 {mu}R/h, which their mean value are 14.33 and 12.62 {mu}R/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  4. Estimation of delivered doses to the fetus in a external radiation therapy treatment of megavoltage

    International Nuclear Information System (INIS)

    Ruggeri, Ricardo M.; Mairal, Liliana; Scarabino, Mara L.; Colombo, Soledad; Sardi, Mabel

    2013-01-01

    This work, stimulated by the entrance to our radiotherapy service several cases of central nervous system injury in pregnant patients, involves the estimation of doses to the fetus from the comparative analysis and verification of theoretical and experimental data. Um phantom was designed with the pregnant morphology about 28 weeks gestation, with inserts for waterproof ionization chamber in the head and abdominal area. From the scan of the anthropomorphic phantom were reproduced in 3D planner treatments comprised of pregnant patients, estimating the dose in the lesion and at different points in the abdominal area. With the phantom in the beam of radiation treatment conditions were measured with the camera dose at the same points of the abdomen mentioned and the isocenter of the injury. The dose was also measured on surface of the abdominal area with diode array to establish correlation with the measured dose ionization chamber calibrated with water. The work provided medical radiotherapists fundamental experimental data for elevated risk assessment framework for radiation protection of the fetus. It also set the reference calibration for in vivo dosimetry in the abdominal area in pregnant patients treated for external radiotherapy. The results obtained with the implemented dosimetry design will determine the procedures that will form the operating rules institution and thus how professionals working within it

  5. Estimate on external effective doses received by the Iranian population from environmental gamma radiation sources

    International Nuclear Information System (INIS)

    Roozitalab, J.; Reza deevband, M.; Rastkhah, N.; Sohrabi, M.

    2006-01-01

    Concentration of natural radioactive materials, especially available U 238, Ra 226, Th 232, and K 40 in construction materials and soil, as well as absorb dose from cosmic rays, is the most important source of the people for effective doses from the environment radiation. In order to evaluate external effective dose, it has been carried out more than 1000 measurements in 36 cities by sensitive dosimeters to environmental gamma radiation for indoor and outdoor conditions in residential areas; which its results show that range of gamma exposure for inside of buildings in Iran is 8.7-20.5 μR/h, and outdoor environments of different cities is 7.9-20.6 μR/h, which their mean value are 14.33 and 12.62 μR/h respectively. Meanwhile, it has been estimated that beam-absorbing ratio between indoor and outdoor in measured environments is 1.55, except contribution of cosmic rays. This studies show that average effective dose for each Iranian person from environmental gamma is 96.9 n Sv/h, and annually effective dose for every person is 0.848 mSv. (authors)

  6. External radiation monitoring in TAPS and RAPS environs (1980-81) using TLD

    International Nuclear Information System (INIS)

    Basu, A.S.; Nambi, K.S.V.; Sunta, C.M.

    1983-01-01

    Results of environmental external radiation monitoring using quarterly integrated TLD measurements are presented for environments of the Tarapur Atomic Power Station (TAPS) and the Rajasthan Atomic Power Station (RAPS) for the two year monitoring period (1980-81). The data fit into the unimodal log-normal distribution except for locations where gaseous radioactivity escaping from the plant makes a significant contribution. The average natural radiation background in TAPS and RAPS environment is estimated to be 59.6 +- 4.7 mR yr -1 and 65.1 +- 9.8 mR yr -1 respectively. Contribution from the plant superimposed over the natural level leads frequently to bi-normal distribution. The effect of stack-released gaseous radioactivity is seen in locations within 1.6 km of TAPS: for example Ghivoli village registered an excess of 9.3 mR yr -1 over the natural background. The quarterly background values indicate minor temporal and spatial variations which can be attributed to changes in natural as well as stack released radioactivity. (author)

  7. Monitor unit calculations for external photon and electron beams: Report of the AAPM Therapy Physics Committee Task Group No. 71

    Energy Technology Data Exchange (ETDEWEB)

    Gibbons, John P., E-mail: john.gibbons@marybird.com [Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, Louisiana 70809 (United States); Antolak, John A. [Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Followill, David S. [Department of Radiation Physics, UT M.D. Anderson Cancer Center, Houston, Texas 77030 (United States); Huq, M. Saiful [Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15232 (United States); Klein, Eric E. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Lam, Kwok L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States); Palta, Jatinder R. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Roback, Donald M. [Department of Radiation Oncology, Cancer Centers of North Carolina, Raleigh, North Carolina 27607 (United States); Reid, Mark [Department of Medical Physics, Fletcher-Allen Health Care, Burlington, Vermont 05401 (United States); Khan, Faiz M. [Department of Radiation Oncology, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-03-15

    A protocol is presented for the calculation of monitor units (MU) for photon and electron beams, delivered with and without beam modifiers, for constant source-surface distance (SSD) and source-axis distance (SAD) setups. This protocol was written by Task Group 71 of the Therapy Physics Committee of the American Association of Physicists in Medicine (AAPM) and has been formally approved by the AAPM for clinical use. The protocol defines the nomenclature for the dosimetric quantities used in these calculations, along with instructions for their determination and measurement. Calculations are made using the dose per MU under normalization conditions, D{sub 0}{sup ′}, that is determined for each user's photon and electron beams. For electron beams, the depth of normalization is taken to be the depth of maximum dose along the central axis for the same field incident on a water phantom at the same SSD, where D{sub 0}{sup ′} = 1 cGy/MU. For photon beams, this task group recommends that a normalization depth of 10 cm be selected, where an energy-dependent D{sub 0}{sup ′} ≤ 1 cGy/MU is required. This recommendation differs from the more common approach of a normalization depth of d{sub m}, with D{sub 0}{sup ′} = 1 cGy/MU, although both systems are acceptable within the current protocol. For photon beams, the formalism includes the use of blocked fields, physical or dynamic wedges, and (static) multileaf collimation. No formalism is provided for intensity modulated radiation therapy calculations, although some general considerations and a review of current calculation techniques are included. For electron beams, the formalism provides for calculations at the standard and extended SSDs using either an effective SSD or an air-gap correction factor. Example tables and problems are included to illustrate the basic concepts within the presented formalism.

  8. Radiation Re-solution Calculation in Uranium-Silicide Fuels

    International Nuclear Information System (INIS)

    Matthews, Christopher; Andersson, Anders David Ragnar; Unal, Cetin

    2017-01-01

    The release of fission gas from nuclear fuels is of primary concern for safe operation of nuclear power plants. Although the production of fission gas atoms can be easily calculated from the fission rate in the fuel and the average yield of fission gas, the actual diffusion, behavior, and ultimate escape of fission gas from nuclear fuel depends on many other variables. As fission gas diffuses through the fuel grain, it tends to collect into intra-granular bubbles, as portrayed in Figure 1.1. These bubbles continue to grow due to absorption of single gas atoms. Simultaneously, passing fission fragments can cause collisions in the bubble that result in gas atoms being knocked back into the grain. This so called ''re-solution'' event results in a transient equilibrium of single gas atoms within the grain. As single gas atoms progress through the grain, they will eventually collect along grain boundaries, creating inter-granular bubbles. As the inter-granular bubbles grow over time, they will interconnect with other grain-face bubbles until a pathway is created to the outside of the fuel surface, at which point the highly pressurized inter-granular bubbles will expel their contents into the fuel plenum. This last process is the primary cause of fission gas release. From the simple description above, it is clear there are several parameters that ultimately affect fission gas release, including the diffusivity of single gas atoms, the absorption and knockout rate of single gas atoms in intra-granular bubbles, and the growth and interlinkage of intergranular bubbles. Of these, the knockout, or re-solution rate has an particularly important role in determining the transient concentration of single gas atoms in the grain. The re-solution rate will be explored in the following sections with regards to uranium-silicide fuels in order to support future models of fission gas bubble behavior.

  9. Goal based mesh adaptivity for fixed source radiation transport calculations

    International Nuclear Information System (INIS)

    Baker, C.M.J.; Buchan, A.G.; Pain, C.C.; Tollit, B.S.; Goffin, M.A.; Merton, S.R.; Warner, P.

    2013-01-01

    Highlights: ► Derives an anisotropic goal based error measure for shielding problems. ► Reduces the error in the detector response by optimizing the finite element mesh. ► Anisotropic adaptivity captures material interfaces using fewer elements than AMR. ► A new residual based on the numerical scheme chosen forms the error measure. ► The error measure also combines the forward and adjoint metrics in a novel way. - Abstract: In this paper, the application of goal based error measures for anisotropic adaptivity applied to shielding problems in which a detector is present is explored. Goal based adaptivity is important when the response of a detector is required to ensure that dose limits are adhered to. To achieve this, a dual (adjoint) problem is solved which solves the neutron transport equation in terms of the response variables, in this case the detector response. The methods presented can be applied to general finite element solvers, however, the derivation of the residuals are dependent on the underlying finite element scheme which is also discussed in this paper. Once error metrics for the forward and adjoint solutions have been formed they are combined using a novel approach. The two metrics are combined by forming the minimum ellipsoid that covers both the error metrics rather than taking the maximum ellipsoid that is contained within the metrics. Another novel approach used within this paper is the construction of the residual. The residual, used to form the goal based error metrics, is calculated from the subgrid scale correction which is inherent in the underlying spatial discretisation employed

  10. Program system for calculating streaming neutron radiation field in reactor cavity

    International Nuclear Information System (INIS)

    He Zhongliang; Zhao Shu.

    1986-01-01

    The A23 neutron albedo data base based on Monte Carlo method well agrees with SAIL albedo data base. RSCAM program system, using Monte Carlo method with albedo approach, is used to calculate streaming neutron radiation field in reactor cavity and containment operating hall. The dose rate distributions calculated with RSCAM in square concrete duct well agree with experiments

  11. Calculation of the radiation force on a cylinder in a standing wave acoustic field

    Energy Technology Data Exchange (ETDEWEB)

    Haydock, David [Unilever R and D Colworth, Sharnbrook, Bedford MK44 1LQ (United Kingdom); Department of Physics, Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom)

    2005-04-15

    We present a new calculation of the radiation force on a cylinder in a standing wave acoustic field. We use the formula to calculate the force on a cylinder which is free to move in the field and one which is fixed in space.

  12. Calculation of the radiation force on a cylinder in a standing wave acoustic field

    International Nuclear Information System (INIS)

    Haydock, David

    2005-01-01

    We present a new calculation of the radiation force on a cylinder in a standing wave acoustic field. We use the formula to calculate the force on a cylinder which is free to move in the field and one which is fixed in space

  13. A comparison of two methods for estimating the technical costs of external beam radiation therapy

    International Nuclear Information System (INIS)

    Hayman, James A.; Lash, Kathy A.; Tao, May L.; Halman, Marc A.

    2000-01-01

    Purpose: To accurately assess the cost-effectiveness of treatment with external beam radiation, it is necessary to have accurate estimates of its cost. One of the most common methods for estimating technical costs has been to convert Medicare charges into costs using Medicare Cost-to-Charge Ratios (CCR). More recently, health care organizations have begun to invest in sophisticated cost-accounting systems (CAS) that are capable of providing procedure-specific cost estimates. The purpose of this study was to examine whether these competing approaches result in similar cost estimates for four typical courses of external beam radiation therapy (EBRT). Methods and Materials: Technical costs were estimated for the following treatment courses: 1) a palliative 'simple' course of 10 fractions using a single field without blocks; 2) a palliative 'complex' course of 10 fractions using two opposed fields with custom blocks; 3) a curative course of 30 fractions for breast cancer using tangent fields followed by an electron beam boost; and 4) a curative course of 35 fractions for prostate cancer using CT-planning and a 4-field technique. Costs were estimated using the CCR approach by multiplying the number of units of each procedure billed by its Medicare charge and CCR and then summing these costs. Procedure-specific cost estimates were obtained from a cost-accounting system, and overall costs were then estimated for the CAS approach by multiplying the number of units billed by the appropriate unit cost estimate and then summing these costs. All costs were estimated using data from 1997. The analysis was also repeated using data from another academic institution to estimate their costs using the CCR and CAS methods, as well as the appropriate relative value units (RVUs) and conversion factor from the 1997 Medicare Fee Schedule to estimate Medicare reimbursement for the four treatment courses. Results: The estimated technical costs for the CCR vs. CAS approaches for the four

  14. Improving efficiency and safety in external beam radiation therapy treatment delivery using a Kaizen approach.

    Science.gov (United States)

    Kapur, Ajay; Adair, Nilda; O'Brien, Mildred; Naparstek, Nikoleta; Cangelosi, Thomas; Zuvic, Petrina; Joseph, Sherin; Meier, Jason; Bloom, Beatrice; Potters, Louis

    Modern external beam radiation therapy treatment delivery processes potentially increase the number of tasks to be performed by therapists and thus opportunities for errors, yet the need to treat a large number of patients daily requires a balanced allocation of time per treatment slot. The goal of this work was to streamline the underlying workflow in such time-interval constrained processes to enhance both execution efficiency and active safety surveillance using a Kaizen approach. A Kaizen project was initiated by mapping the workflow within each treatment slot for 3 Varian TrueBeam linear accelerators. More than 90 steps were identified, and average execution times for each were measured. The time-consuming steps were stratified into a 2 × 2 matrix arranged by potential workflow improvement versus the level of corrective effort required. A work plan was created to launch initiatives with high potential for workflow improvement but modest effort to implement. Time spent on safety surveillance and average durations of treatment slots were used to assess corresponding workflow improvements. Three initiatives were implemented to mitigate unnecessary therapist motion, overprocessing of data, and wait time for data transfer defects, respectively. A fourth initiative was implemented to make the division of labor by treating therapists as well as peer review more explicit. The average duration of treatment slots reduced by 6.7% in the 9 months following implementation of the initiatives (P = .001). A reduction of 21% in duration of treatment slots was observed on 1 of the machines (P Kaizen approach has the potential to improve operational efficiency and safety with quick turnaround in radiation therapy practice by addressing non-value-adding steps characteristic of individual department workflows. Higher effort opportunities are identified to guide continual downstream quality improvements. Copyright © 2017 American Society for Radiation Oncology. Published by

  15. Cosmic radiation shielding properties of COLUMBUS and REMSIM multi-layer external shells

    Science.gov (United States)

    Durante, Marco; Manti, Lorenzo; Rusek, Adam; Belluco, Maurizio; Lobascio, Cesare

    The European module COLUMBUS has been recently installed on the International Space Station. Future plans for exploration involve the use of inflatable modules, such as the REMSIM concept proposed in a previous ESA funded study. We studied the radiation shielding properties of COLUMBUS and REMSIM external shell using 1 GeV/n Feor H-ions accelerated at the NASA Space Radiation Laboratory at the Brookhaven National Laboratory (Long Island, NY, USA). COLUMBUS has a 22 mm rigid multi-layer shell with Al, Nextel and Kevlar, as materials of the double bumper for meteoroids and debris protection, MLI for thermal reasons and again Al as pressure shell. Inside the module, astronauts are further protected by secondary structures, including racks, a number of electronic devices and payload equipment. This internal equipment has been simulated using Al and Kevlar, bringing the total thickness to about 15 g/cm2. REMSIM consists of a thermal multi-layer (MLI), four Nextel layers used to provide shock of the impacting micro-meteoroids, a ballistic restraint multi-layer of Kevlar used to absorb debris cloud's kinetic energy, a Kevlar structural restraint to support pressure loads incurred from inflating the module. To contain air inside the module, REMSIM adopts three layers of airtight material separated by two layers of Kevlar (air bladder). A final layer of Nomex provide protection against punctures and fire. In the flight configuration there are also spacer elements (foam) needed to guarantee correct spacing between consecutive bumper layers. These spacers were not included in the tests, making the total thickness about 1.1 cm. The internal equipment in REMSIM was not been defined, but due to its application for exploration missions it was decided to exploit water, valuable resource used for drinking, washing and technical usage, as a radiation shielding. In this test, we have included about 8 cm of water. Measured dose attenuation shows that the Columbus module reduces the

  16. Impact of cradle immobilization on setup reproducibility during external beam radiation therapy for lung cancer

    International Nuclear Information System (INIS)

    Bentel, Gunilla C.; Marks, Lawrence B.; Krishnamurthy, Rupa

    1997-01-01

    Purpose: To compare the setup accuracy during fractionated radiation therapy for two patient groups with lung cancer treated with and without an immobilization cradle. Methods: Three hundred ninety-seven port films from 30 patients immobilized in the Alpha Cradle TM1 were compared with 329 port films from 30 patients who were not immobilized with the cradle. All patients were treated with curative intent for nonmetastatic lung cancer. The frequency of physician-requested isocenter shifts were compared in the two groups using a two-tailed chi-square test. Initial port films taken on the first day of treatment, routine films taken usually weekly during radiation therapy, and requested films taken after a requested shift were considered separately. The immobilization device consisted of a custom-made foam cradle that extended from above the head to the knees. Patients were generally treated with their arms above their heads, and treatment setup marks in the immobilized patients were placed on both the patients' skin and the immobilization cradle. For the noncradle patients, setup marks were placed only on the patients' skin. Results: For the routine films, the frequency of physician-requested isocenter shifts was lower in immobilized patients than in the nonimmobilized group (p = 0.139). Most of this reduction was seen on oblique fields (p = 0.038). No benefits were seen among initial or requested films. The two groups were well balanced with regard to stage, age, field size, and total dose. Conclusions: The use of aggressive immobilization improves the setup reproducibility in patients receiving external beam radiation therapy for lung cancer, especially during treatment with oblique fields. This improvement in treatment accuracy might improve the therapeutic ratio

  17. The Eddington approximation calculation of radiation flux in the atmosphere–ocean system

    International Nuclear Information System (INIS)

    Shi, Chong; Nakajima, Teruyuki

    2015-01-01

    An analytical approximation method is presented to calculate the radiation flux in the atmosphere–ocean system using the Eddington approximation when the upwelling radiation from the ocean body is negligibly small. Numerical experiments were carried out to investigate the feasibility of the method in two cases: flat and rough ocean surfaces. The results show good consistency for the reflectivity at the top of atmosphere and transmissivity just above the ocean surface, in comparison with the exact values calculated by radiative transfer models in each case. Moreover, an obvious error might be introduced for the calculation of radiation flux at larger solar zenith angles when the roughness of the ocean surface is neglected. - Highlights: • The Eddington approximation method is extended to the atmosphere–ocean system. • The roughness of ocean surface cannot be neglected at lager solar zenith angles. • Unidirectional reflectivity for rough ocean surface is proposed

  18. The simple analytical method for scattered radiation calculation in contrast X-ray diagnostic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Markovic, S; Pavlovic, R [Inst. of Nuclear Science Vinca, Belgrade (Yugoslavia). Radiation and Environmental Protection Lab.; Boreli, F [Fac. of Electrical Engineering, Belgrade (Yugoslavia)

    1996-12-31

    In realization of radiation protection measures for medical staff present during diagnostic procedures, the necessary condition is knowledge of the space - energy distributions of the scattered radiation from the patient. In this paper, the simple calculation procedure for the scattered radiation field of the actual diagnostic energies is presented. Starting from the single Compton scattering model and using the justified transformations the final equations in elementary form are derived. For numerical calculations the computer code ANGIO was created. The calculated results were confirmed by detailed dosimetric measurements of the scattered field around patient (the water phantom) in SSDL in the Institute of nuclear sciences `Vinca`, Belgrade. These results are good base for assessment of irradiation. The main irradiation source for the physician and the other members of the medical team is the back scattered radiation from patient - albedo. (author). 3 figs., 3 refs.

  19. Development and External Validation of the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer: Comparison with Two Western Risk Calculators in an Asian Cohort.

    Science.gov (United States)

    Park, Jae Young; Yoon, Sungroh; Park, Man Sik; Choi, Hoon; Bae, Jae Hyun; Moon, Du Geon; Hong, Sung Kyu; Lee, Sang Eun; Park, Chanwang; Byun, Seok-Soo

    2017-01-01

    We developed the Korean Prostate Cancer Risk Calculator for High-Grade Prostate Cancer (KPCRC-HG) that predicts the probability of prostate cancer (PC) of Gleason score 7 or higher at the initial prostate biopsy in a Korean cohort (http://acl.snu.ac.kr/PCRC/RISC/). In addition, KPCRC-HG was validated and compared with internet-based Western risk calculators in a validation cohort. Using a logistic regression model, KPCRC-HG was developed based on the data from 602 previously unscreened Korean men who underwent initial prostate biopsies. Using 2,313 cases in a validation cohort, KPCRC-HG was compared with the European Randomized Study of Screening for PC Risk Calculator for high-grade cancer (ERSPCRC-HG) and the Prostate Cancer Prevention Trial Risk Calculator 2.0 for high-grade cancer (PCPTRC-HG). The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC) and calibration plots. PC was detected in 172 (28.6%) men, 120 (19.9%) of whom had PC of Gleason score 7 or higher. Independent predictors included prostate-specific antigen levels, digital rectal examination findings, transrectal ultrasound findings, and prostate volume. The AUC of the KPCRC-HG (0.84) was higher than that of the PCPTRC-HG (0.79, pexternal validation. Calibration plots also revealed better performance of KPCRC-HG and ERSPCRC-HG than that of PCPTRC-HG on external validation. At a cut-off of 5% for KPCRC-HG, 253 of the 2,313 men (11%) would not have been biopsied, and 14 of the 614 PC cases with Gleason score 7 or higher (2%) would not have been diagnosed. KPCRC-HG is the first web-based high-grade prostate cancer prediction model in Korea. It had higher predictive accuracy than PCPTRC-HG in a Korean population and showed similar performance with ERSPCRC-HG in a Korean population. This prediction model could help avoid unnecessary biopsy and reduce overdiagnosis and overtreatment in clinical settings.

  20. Deterministic and stochastic methods of calculation of polarization characteristics of radiation in natural environment

    Science.gov (United States)

    Strelkov, S. A.; Sushkevich, T. A.; Maksakova, S. V.

    2017-11-01

    We are talking about russian achievements of the world level in the theory of radiation transfer, taking into account its polarization in natural media and the current scientific potential developing in Russia, which adequately provides the methodological basis for theoretically-calculated research of radiation processes and radiation fields in natural media using supercomputers and mass parallelism. A new version of the matrix transfer operator is proposed for solving problems of polarized radiation transfer in heterogeneous media by the method of influence functions, when deterministic and stochastic methods can be combined.

  1. A grey diffusion acceleration method for time-dependent radiative transfer calculations: analysis and application

    International Nuclear Information System (INIS)

    Nowak, P.F.

    1993-01-01

    A grey diffusion acceleration method is presented and is shown by Fourier analysis and test calculations to be effective in accelerating radiative transfer calculations. The spectral radius is bounded by 0.9 for the continuous equations, but is significantly smaller for the discretized equations, especially in the optically thick regimes characteristic to radiation transport problems. The GDA method is more efficient than the multigroup DSA method because its slightly higher iteration count is more than offset by the much lower cost per iteration. A wide range of test calculations confirm the efficiency of GDA compared to multifrequency DSA. (orig.)

  2. Calculation analysis of the thickness of radiation shield for the RIA equipment IP10

    International Nuclear Information System (INIS)

    Benar Bukit; Kristiyanti; Hari Nurcahyadi

    2011-01-01

    Calculation Analysis has been performed on the thickness of radiation shield for the design of the Radioimmunoassay (RIA) IP10 counters using five detectors arranged in parallel. The calculation is intended to ensure that the radiation on each detector does not influence each other. The radiation shield is made of lead. The calculation of lead thickness was based on the principle of the lead plates absorptive power toward the gamma ray of a certain energy. which is the function of linear absorption coefficient and the material thickness. Assuming the use of Iodium-125(I-125) source with an activity 10 µCi, and expecting an absorptive power of 95%, calculations showed that the required lead thickness is equal to 0,013 cm. Since lead is soft and its availability in the market is limited, lead plate of 2 mm thickness are used instead, so that counting result for the detectors do not influence each other. (author)

  3. Measurement and calculation of radiation sources in the primary cooling system of JOYO

    International Nuclear Information System (INIS)

    Suzuki, S.; Iizawa, K.; Ohtani, N.; Kobayashi, T.; Horie, J.; Handa, H.

    1987-01-01

    Production and transfer of radiation sources in the primary cooling system are important consideration in the LMFBR plant from the viewpoint of radiation protection and shielding design. These items were evaluated with calculations and/or measurements in the Japanese experimental fast reactor JOYO. In this study, calculations were made with the DOT3.5 0 two-dimensional discrete ordinate transport code to determine the neutron flux and production rate distributions of radiation sources in the reactor vessel. Using the DOT results, the behavior in primary coolant sodium of the CP (radioactive corrosion products) which were released from the reactor structural material was also calculationally analyzed with the PSYCHE code developed by PNC. These analytical results were compared with the measured results to get the verification of analysis methods and to estimate the accuracy of calculations

  4. ALMA. Calculations of diffusion and radiation doses in connection with final storage of radioactive wastes

    International Nuclear Information System (INIS)

    Gelin, R.; Kjellbert, N.; Stenquist, C.

    1978-09-01

    Calculations of diffusion and radiation doses in connection with final storage of low-lavel and intermediate-level radioactive wastes. The results show that the doses obtained with realistic values of parameters used in the calculations are very low. However, substantially simplified assumption have been applied in the calculations. Thus more detailed models for the description of the diffusion process have to be developed. (E.R.)

  5. Natural radioactivity and external gamma radiation exposure at the coastal Red Sea in Egypt

    International Nuclear Information System (INIS)

    Harb, S.

    2008-01-01

    Radionuclides which present in different beach sands are sources of external exposure that contribute to the total radiation exposure of human. In this work, superficial samples of beach sand were collected from the Red Sea coastline (Ras Gharib, Hurghada, Safaga, Qusier and Marsa Alam areas) and at 20 km on Qena-Safaga road. The distribution of natural radionuclides in sand beach samples was studied by gamma spectrometry. The activity concentrations of primordial and artificial radionuclides in samples that are collected from the coastal environment of the Red Sea were 19.2 ± 3 Bq kg -1 for 210 Pb, 21.1 ± 1 Bq kg -1 for 226 Ra, 22.7 ± 2 Bq kg -1 for 238 U, 1.0 ± 0.1 Bq kg -1 for 235 U, 11.6 ± 1 Bq kg -1 for 228 Ra, 13.0 ± 1 Bq kg -1 for 228 Th, 12.4 ± 1 Bq kg -1 for 232 Th, 930 ± 32 Bq kg -1 for 40 K and 1.2 ± 0.3 Bq kg -1 for 137 Cs. The mean external gamma-dose rate was 62.5 ± 3.2 nSv h -1 , 54.4 ± 2.8 nGy h -1 Ra equivalent activity (Ra eq ) was 107 ± 5.8 Bq kg -1 , 0.86 ± 0.04 Bq kg -1 for representative level index (Iγ) and effective dose rate was 0.067 ± 0.003 mSv y -1 in beach sand red sea, in air due to naturally occurring radionuclides. (authors)

  6. Monte Carlo calculation of scattered radiation from applicators in low energy clinical electron beams

    International Nuclear Information System (INIS)

    Jabbari, N.; Hashemi-Malayeri, B.; Farajollahi, A. R.; Kazemnejad, A.

    2007-01-01

    In radiotherapy with electron beams, scattered radiation from an electron applicator influences the dose distribution in the patient. The contribution of this radiation to the patient dose is significant, even in modern accelerators. In most of radiotherapy treatment planning systems, this component is not explicitly included. In addition, the scattered radiation produced by applicators varies based on the applicator design as well as the field size and distance from the applicators. The aim of this study was to calculate the amount of scattered dose contribution from applicators. We also tried to provide an extensive set of calculated data that could be used as input or benchmark data for advanced treatment planning systems that use Monte Carlo algorithms for dose distribution calculations. Electron beams produced by a NEPTUN 10PC medical linac were modeled using the BEAMnrc system. Central axis depth dose curves of the electron beams were measured and calculated, with and without the applicators in place, for different field sizes and energies. The scattered radiation from the applicators was determined by subtracting the central axis depth dose curves obtained without the applicators from that with the applicator. The results of this study indicated that the scattered radiation from the electron applicators of the NEPTUN 10PC is significant and cannot be neglected in advanced treatment planning systems. Furthermore, our results showed that the scattered radiation depends on the field size and decreases almost linearly with depth. (author)

  7. Muscle invasive bladder cancer treated by transurethral resection, followed by external beam radiation and interstitial iridium-192

    NARCIS (Netherlands)

    A. Wijnmaalen (Arendjan); P.A. Helle (Peter); P.C.M. Koper (Peter); P.P. Jansen (Peter); P. Hanssens (Patrick); C.G.G. Boeken Kruger (Cornelis); W.L.J. van Putten (Wim)

    1997-01-01

    textabstractPurpose: To evaluate the results of transurethral resection (TUR), external beam radiotherapy (EBRT), and interstitial radiation (IRT) with iridium-192, using the afterloading technique in patients with muscle invasive bladder cancer. Methods and Materials: From May 1989 until September

  8. ACR Appropriateness Criteria for external beam radiation therapy treatment planning for clinically localized prostate cancer, part II of II

    Directory of Open Access Journals (Sweden)

    Nicholas G. Zaorsky, MD

    2017-07-01

    Conclusions: External beam radiation is a key component of the curative management of T1 and T2 prostate cancer. By combining the most recent medical literature, these Appropriateness Criteria can aid clinicians in determining the appropriate treatment delivery and personalized approaches for individual patients.

  9. Clinical Implications of TiGRT Algorithm for External Audit in Radiation Oncology.

    Science.gov (United States)

    Shahbazi-Gahrouei, Daryoush; Saeb, Mohsen; Monadi, Shahram; Jabbari, Iraj

    2017-01-01

    Performing audits play an important role in quality assurance program in radiation oncology. Among different algorithms, TiGRT is one of the common application software for dose calculation. This study aimed to clinical implications of TiGRT algorithm to measure dose and compared to calculated dose delivered to the patients for a variety of cases, with and without the presence of inhomogeneities and beam modifiers. Nonhomogeneous phantom as quality dose verification phantom, Farmer ionization chambers, and PC-electrometer (Sun Nuclear, USA) as a reference class electrometer was employed throughout the audit in linear accelerators 6 and 18 MV energies (Siemens ONCOR Impression Plus, Germany). Seven test cases were performed using semi CIRS phantom. In homogeneous regions and simple plans for both energies, there was a good agreement between measured and treatment planning system calculated dose. Their relative error was found to be between 0.8% and 3% which is acceptable for audit, but in nonhomogeneous organs, such as lung, a few errors were observed. In complex treatment plans, when wedge or shield in the way of energy is used, the error was in the accepted criteria. In complex beam plans, the difference between measured and calculated dose was found to be 2%-3%. All differences were obtained between 0.4% and 1%. A good consistency was observed for the same type of energy in the homogeneous and nonhomogeneous phantom for the three-dimensional conformal field with a wedge, shield, asymmetric using the TiGRT treatment planning software in studied center. The results revealed that the national status of TPS calculations and dose delivery for 3D conformal radiotherapy was globally within acceptable standards with no major causes for concern.

  10. Clinical Implications of TiGRT Algorithm for External Audit in Radiation Oncology

    Directory of Open Access Journals (Sweden)

    Daryoush Shahbazi-Gahrouei

    2017-01-01

    Full Text Available Background: Performing audits play an important role in quality assurance program in radiation oncology. Among different algorithms, TiGRT is one of the common application software for dose calculation. This study aimed to clinical implications of TiGRT algorithm to measure dose and compared to calculated dose delivered to the patients for a variety of cases, with and without the presence of inhomogeneities and beam modifiers. Materials and Methods: Nonhomogeneous phantom as quality dose verification phantom, Farmer ionization chambers, and PC-electrometer (Sun Nuclear, USA as a reference class electrometer was employed throughout the audit in linear accelerators 6 and 18 MV energies (Siemens ONCOR Impression Plus, Germany. Seven test cases were performed using semi CIRS phantom. Results: In homogeneous regions and simple plans for both energies, there was a good agreement between measured and treatment planning system calculated dose. Their relative error was found to be between 0.8% and 3% which is acceptable for audit, but in nonhomogeneous organs, such as lung, a few errors were observed. In complex treatment plans, when wedge or shield in the way of energy is used, the error was in the accepted criteria. In complex beam plans, the difference between measured and calculated dose was found to be 2%–3%. All differences were obtained between 0.4% and 1%. Conclusions: A good consistency was observed for the same type of energy in the homogeneous and nonhomogeneous phantom for the three-dimensional conformal field with a wedge, shield, asymmetric using the TiGRT treatment planning software in studied center. The results revealed that the national status of TPS calculations and dose delivery for 3D conformal radiotherapy was globally within acceptable standards with no major causes for concern.

  11. Survival rate of patients with differentiated thyroid cancer without early postoperative external radiation of the neck

    International Nuclear Information System (INIS)

    Saur, H.B.; Lerch, H.; Schober, O.

    1996-01-01

    Results of survival rates in differentiated thyroid carcinoma and comparison with a review of literature are given. Four hundred and sixty-four patients with differentiated cancer of the thyroid (354 female, 110 male, range: 6 to 84 years, median: 46.8 years; 275 patients with papillary and 190 with follicular cancer) were analyzed retrospectively. All patients were treated with ablative doses of radioiodine after thyroidectomy including compartment oriented lymphadenectomy in 27 patients. All patients passed an individual systematic follow-up according to risk: 'Low risk' pT≤3NxM0 vs. 'high risk' pT4 and/or M1. Early postoperative radiation was not included even in patients with local invasion (pT4). The corrected 5- and 10-year survival rates for papillary cancer are 0.91 and 0.91, for follicular cancer 0.94 resp. 0.78 (p=0.55), age (≤40 years 0.96 and 0.96, >40 years 0.90 and 0.80; p=0.008), gender (female 0.93 and 0.92, male 0.90 and 0.70; p=0.06) and invasion/distant metastases (pT4 and/or M1 0.83 and 0.71, other 0.97 and 0.97; p=0.0001). A systematic follow-up with an individually adapted standardized scheme is associated with high survival rates in patients with differentiated cancer of the thyroid. Early diagnosis of recurrences, locoregional lymph node and distant metastases with early surgical treatment including compartment oriented lymphadenectomy and radioiodine therapy yield high survival even without external radiation. (orig./MG) [de

  12. The relationship between technical parameters of external beam radiation therapy and complications for localized prostate cancer

    International Nuclear Information System (INIS)

    Kitamura, Kei; Shirato, Hiroki; Suzuki, Keishiro

    2000-01-01

    This study was performed to review retrospectively the clinical course of chronic rectal bleeding as a complication of external beam radiation therapy for localized prostate cancer and to analyze the relationship between technical parameters of radiation therapy and the complications. Seventy-one patients with stages A2, B and C were treated with local-field radiotherapy (total dose 52.5-66 Gy, daily dose 2.0-3.28 Gy, field area 30-81 cm 2 , number of fields 3-15 ports, planning simulations X-ray or CT-based) between 1989 and 1998 at three institutions. The protocols were consistent during this same period at these institutions. Multivariate analysis revealed pretreatment PSA and Gleason sum to be statistically significant predictors of 5 year prostatic specific antigen (PSA) relapse-free rates in a median follow-up period of 42 months (range 12-119 months). The significant risk factors for higher grading of acute morbidity were a biological equivalent dose, α/β=10 (BED 10 ) ≥65 Gy, dose per fraction ≥3.0 Gy, field area ≥42 cm 2 , fewer ports and X-ray planning simulation. However, no parameter was associated with higher grading of late morbidity. Eleven patients (15.4%) experienced a late GI complication: grade 1 (4.2%), grade 2 (9.8%), grade 3 (1.4%). The median time to occurrence of rectal bleeding was 12 months after radiotherapy and the mean duration of morbidity was 11 months. Higher total dose and dose per fraction, larger field area, fewer ports and X-ray simulation increased the grades of acute morbidity. A majority of chronic rectal bleedings were transient and responded to conservative treatment. (author)

  13. Radiation optic neuropathy after megavoltage external-beam irradiation: Analysis of time-dose factors

    International Nuclear Information System (INIS)

    Parsons, J.T.; Bova, F.J.; Million, R.R.

    1994-01-01

    To investigate the risk of radiation-induced optic neuropathy according to total radiotherapy dose and fraction size, based on both retrospective and prospectively collected data. Between October 1964 and May 1989, 215 optic nerves in 131 patients received fractionated external-beam irradiation during the treatment of primary extracranial head and neck tumors. All patients had a minimum of 3 years of ophthalmologic follow-up (range, 3 to 21 years). The clinical end point was visual acuity of 20/100 or worse as a result of optic nerve injury. Anterior ischemic optic neuropathy developed in five nerves (at mean and median times of 32 and 30 months, respectively, and a range of 2-4 years). Retrobulbar optic neuropathy developed in 12 nerves (at mean and median times of 47 and 28 months, respectively, and a range of 1-14 years). No injuries were observed in 106 optic nerves that received a total dose of <59 Gy. Among nerves that received doses of ≥ 60 Gy, the dose per fraction was more important than the total dose in producing optic neuropathy. The 15-year actuarial risk of optic compared with 47% when given in fraction sizes ≥1.9 Gy. The data also suggest an increased risk of optic nerve injury with increasing age. As there is no effective treatment of radiation-induced optic neuropathy, efforts should be directed at its prevention by minimizing the total dose, paying attention to the dose per fraction to the nerve, and using reduced field techniques where appropriate to limit the volume of tissues that receive high-dose irradiation. 32 refs., 5 figs., 5 tabs

  14. Targeted Intraoperative Radiotherapy for Breast Cancer in Patients in Whom External Beam Radiation Is Not Possible

    International Nuclear Information System (INIS)

    Keshtgar, Mohammed R.S.; Vaidya, Jayant S.; Tobias, Jeffrey S.; Wenz, Frederik; Joseph, David; Stacey, Chris; Metaxas, Marinos G.; Keller, Anke; Corica, Tammy; Williams, Norman R.; Baum, Michael

    2011-01-01

    Purpose: External beam radiation therapy (EBRT) following wide local excision of the primary tumor is the standard treatment in early breast cancer. In some circumstances this procedure is not possible or is contraindicated or difficult. The purpose of this study was to determine the safety and efficacy of targeted intraoperative radiotherapy (TARGIT) when EBRT is not feasible. Methods and Materials: We report our experience with TARGIT in three centers (Australia, Germany, and the United Kingdom) between 1999 and 2008. Patients at these centers received a single radiation dose of 20 Gy to the breast tissue in contact with the applicator (or 6 Gy at 1-cm distance), as they could not be given EBRT and were keen to avoid mastectomy. Results: Eighty patients were treated with TARGIT. Reasons for using TARGIT were 21 patients had previously received EBRT, and 31 patients had clinical reasons such as systemic lupus erythematosus, motor neuron disease, Parkinson's disease, ankylosing spondylitis, morbid obesity, and cardiovascular or severe respiratory disease. Three of these patients received percutaneous radiotherapy without surgery; 28 patients were included for compelling personal reasons, usually on compassionate grounds. After a median follow-up of 38 months, only two local recurrences were observed, an annual local recurrence rate of 0.75% (95% confidence interval, 0.09%-2.70%). Conclusions: While we await the results of the randomized trial (over 2,000 patients have already been recruited), TARGIT is an acceptable option but only in highly selected cases that cannot be recruited in the trial and in whom EBRT is not feasible/possible.

  15. Radioactivity in food and the environment: calculations of UK radiation doses using integrated methods

    International Nuclear Information System (INIS)

    Allott, Rob

    2003-01-01

    Dear Sir: I read with interest the paper by W C Camplin, G P Brownless, G D Round, K Winpenny and G J Hunt from the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) on 'Radioactivity in food and the environment: calculations of UK radiation doses using integrated methods' in the December 2002 issue of this journal (J. Radiol. Prot. 22 371-88). The Environment Agency has a keen interest in the development of a robust methodology for assessing total doses which have been received by members of the public from authorised discharges of radioactive substances to the environment. Total dose in this context means the dose received from all authorised discharges and all exposure pathways (e.g. inhalation, external irradiation from radionuclides in sediment/soil, direct radiation from operations on a nuclear site, consumption of food etc). I chair a 'total retrospective dose assessment' working group with representatives from the Scottish Environment Protection Agency (SEPA), Food Standards Agency (FSA), National Radiological Protection Board, CEFAS and BNFL which began discussing precisely this issue during 2002. This group is a sub-group of the National Dose Assessment Working Group which was set up in April 2002 (J. Radiol. Prot. 22 318-9). The Environment Agency, Food Standards Agency and the Nuclear Installations Inspectorate previously undertook joint research into the most appropriate methodology to use for total dose assessment (J J Hancox, S J Stansby and M C Thorne 2002 The Development of a Methodology to Assess Population Doses from Multiple Source and Exposure Pathways of Radioactivity (Environment Agency R and D Technical Report P3-070/TR). This work came to broadly the same conclusion as the work by CEFAS, that an individual dose method is probably the most appropriate method to use. This research and that undertaken by CEFAS will help the total retrospective dose assessment working group refine a set of principles and a methodology for the

  16. The system of personal monitoring and the evaluation of occupational exposure to external ionizing radiation in Cuba

    International Nuclear Information System (INIS)

    Molina, Daniel; Castro, Ailza; Martinez, Ernesto; Pernas, Rene

    2008-01-01

    Full text: Personal monitoring of workers is recommended or required by the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. In our country the personal monitoring of external exposure to ionizing radiation is carried out by External Dosimetry Laboratory (LDE) of the Center for Radiation Protection and Hygiene (CPHR). We have implemented an individual monitoring service based on thermoluminescence dosimetry system. The service includes whole body and extremity dosimeters. We have two systems; one is base on a manual Toledo TLD reader and the other on an automatic RADOS TLD system. This service is recognized by the National Regulatory Authority in the field of radiation protection and safety. We have implemented a quality assurance (QA) programme designed according to the recommendations of the ISO/IEC 17025 standards. The papers deals with the presentation of these QA programme which includes administrative data and information, technical checking of the equipment, acceptance tests of new dosimeters and equipment, issuing and processing of the dosimeters, dose evaluation, record keeping and reporting, traceability, handling of complaints, internal reviews and external audits. The papers also describe the results of occupational exposure for the different practices during 2006-2007 period. (author)

  17. Implication of new CEC recommendations for individual monitoring for external radiation doses to the skin and the extremities

    International Nuclear Information System (INIS)

    Christensen, P.; Julius, H.W.; Marshall, T.O.

    1991-01-01

    A drafting group consisting of the above authors has assisted the CEC in revising the CEC document Technical Recommendations for Monitoring the Exposure to Individuals to External Radiation, EUR 5287, published in 1975. The paper highlights sections of the revised version relating particularly to irradiation of the skin and the extremities and focusses on problems connected to exposure to weakly penetrating radiations. Concepts of individual monitoring for external radiation exposures to the skin of the whole body and to the extremities are discussed and guidance is given as regards dose quantities and dosemeter calibration procedures. A method of quantifying the overall accuracy of the dose measurements as a result of the various uncertainty components connected with the dosimetry system is suggested and requirements on the accuracy of the dose measurements complying with the ICRP requirements on overall accuracy for individual monitoring are specified. Moreover, implications of the accuracy requirements for the design and type testing of the dosemeter are discussed. (author)

  18. External radiation dose from patients received diagnostic doses of 201 T1-Chloride and 99 Tc-MIBI

    International Nuclear Information System (INIS)

    Dadashzadeh, S.; Sattari, A.; Nasiroghli, G.A.

    2002-01-01

    Patients receiving diagnostic doses of radiopharmaceuticals become a source of contamination and exposure for those who come in contact with them, such as nuclear medicine technologists, relatives and nurses. Therefore, the measurement of external radiation dose from these patients is necessary. In this study, the dose rates at distances of 10, 50 and 100 cm from 70 patients who received diagnostic amounts of 201 T1-Chloride and 99 Tc-MIBI was measures. The results showed that the maximum external radiation dose rates for 201 T1 and 99 Tc-MIBI were 18.4 and 75.0 μ Sv.h -1 , respectively, at 5 cm distance from the patients. The average radiation dose received by nuclear medicine technologists, considering their close contact during one working day was 12.5 ± 3.4μ Sv. The highest received dose was 22.7 μSv, which was well below the acceptable dose limit

  19. Comparison of radiation measurements and calculations of reactor surroundings for skyshine analysis

    Energy Technology Data Exchange (ETDEWEB)

    Tsubosaka, A.; Nomura, Y. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kawabe, T. [Japan Research Institute, Limited, Osaka (Japan); Zharkov, V.P.; Kartashev, I.A.; Netecha, M.E.; Orlov, Y.V. [Research and Development Institute of Power Engineering, Moscow (Russian Federation)

    2000-03-01

    ISTC Project 'Experimental Studies of Radiation Scattering in the Atmosphere' were conducted using the IVG-1M and RA reactors by RDIPE in collaboration with IAE NNC RK and JAERI during 1996-1998. The radial distributions of fast neutron flux, thermal neutron flux and gamma radiation dose rate were measured above these two reactors at three heights. Neutron spectra above these two reactors and thermal and fast neutron fluxes over the hollow pipe height in the IVG-1M reactor were also measured in order to determine the radiation characteristics for skyshine analysis. For verifying the computer codes the calculations of reactor surroundings were performed using MCNP and DORT/DOT-3.5. The comparisons between the measurements and the calculations show that MCNP and DORT/DOT-3.5 codes can be widely applied to the shielding problems by selecting properly the calculation conditions. (author)

  20. Risk of Fatal Cerebrovascular Accidents after External Beam Radiation Therapy for Early Stage Glottic Larynx Cancer

    Science.gov (United States)

    Swisher-McClure, Samuel; Mitra, Nandita; Lin, Alexander; Ahn, Peter; Wan, Fei; O’Malley, Bert; Weinstein, Gregory S.; Bekelman, Justin E.

    2013-01-01

    Background This study compared the risk of fatal cerebrovascular accidents (CVA) in patients with early stage glottic larynx cancer receiving surgery or external beam radiation therapy (EBRT). Methods and Materials Using a competing risks survival analysis, we compared the risk of death due to CVA among patients with early stage glottic larynx cancer receiving surgery or EBRT in the SEER database. Results The cumulative incidence of fatal CVA at 15 years was higher in patients receiving EBRT (2.8 %; 95% CI 2.3%–3.4%) compared to surgery (1.5 %; 95% CI 0.8 %–2.3%, p= 0.024). In multivariable competing risks regression models, EBRT remained associated with an increased risk of fatal CVA compared to surgery (adjusted HR 1.75; 95% CI 1.04–2.96, p= 0.037). Conclusion Treatment of early stage glottic larynx cancer with EBRT was associated with a small increase in the risk of late fatal CVA events relative to surgery. PMID:23595858

  1. The role of adjuvant external beam radiation therapy for papillary thyroid carcinoma invading the trachea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Suk; Choi, Jae Hyuck; Kim, Kwang Sik [Jeju National University Hospital, Jeju National University School of Medicine, Jeju (Korea, Republic of); and others

    2017-06-15

    To evaluate the effect of adjuvant external beam radiation therapy (EBRT) on local failure-free survival rate (LFFS) for papillary thyroid cancer (PTC) invading the trachea. Fifty-six patients with locally advanced PTC invading the trachea were treated with surgical resection. After surgery, 21 patients received adjuvant EBRT and radioactive iodine therapy (EBRT group) and 35 patients were treated with radioactive iodine therapy (control group). The age range was 26–87 years (median, 56 years). The median follow-up period was 43 months (range, 4 to 145 months). EBRT doses ranged from 50.4 to 66 Gy (median, 60 Gy). Esophagus invasion and gross residual disease was more frequent in the EBRT group. In the control group, local recurrence developed in 9 (9/35, 26%) and new distant metastasis in 2 (2/35, 6%) patients, occurring 4 to 68 months (median, 37 months) and 53 to 68 months (median, 60 months) after surgery, respectively. Two patients had simultaneous local recurrence and new distant metastasis. There was one local failure in the EBRT group at 18 months after surgery (1/21, 5%). The 5-year LFFS was 95% in the EBRT group and 63% in the control group (p = 0.103). In the EBRT group, one late grade 2 xerostomia was developed. Although, EBRT group had a higher incidence of esophagus invasion and gross residual disease, EBRT group showed a better 5-year LFFS. Adjuvant EBRT may have contributed to the better LFFS in these patients.

  2. Automatic analysis of image quality control for Image Guided Radiation Therapy (IGRT) devices in external radiotherapy

    International Nuclear Information System (INIS)

    Torfeh, Tarraf

    2009-01-01

    On-board imagers mounted on a radiotherapy treatment machine are very effective devices that improve the geometric accuracy of radiation delivery. However, a precise and regular quality control program is required in order to achieve this objective. Our purpose consisted of developing software tools dedicated to an automatic image quality control of IGRT devices used in external radiotherapy: 2D-MV mode for measuring patient position during the treatment using high energy images, 2D-kV mode (low energy images) and 3D Cone Beam Computed Tomography (CBCT) MV or kV mode, used for patient positioning before treatment. Automated analysis of the Winston and Lutz test was also proposed. This test is used for the evaluation of the mechanical aspects of treatment machines on which additional constraints are carried out due to the on-board imagers additional weights. Finally, a technique of generating digital phantoms in order to assess the performance of the proposed software tools is described. Software tools dedicated to an automatic quality control of IGRT devices allow reducing by a factor of 100 the time spent by the medical physics team to analyze the results of controls while improving their accuracy by using objective and reproducible analysis and offering traceability through generating automatic monitoring reports and statistical studies. (author) [fr

  3. Outlines of ICRP publication 74 and new dose conversion coefficients for external radiation

    International Nuclear Information System (INIS)

    Yamaguchi, Yasuhiro

    1998-01-01

    Combined task group of ICRP and ICRU reported the ICRP Publication 74 (1996) which is a summary report of their collection, analysis and evaluation of many data and dose conversion coefficients. Concerning the new coefficients, the author described this review as follows: History until Publication 74. Doses recommended at present: for protection quantity, the mean absorption dose of organ and tissue, equivalent dose and effective dose and for operational quantity, the ambient dose equivalent, directional dose equivalent and individual dose equivalent. Changes which can have an influence on the dose evaluation; introduction of radiation weighting factor (WR), changing of tissue weighting factor (WR), changing of the equation for Q-L relation and updating of physical data. New dose conversion coefficients; for photon, neutron and electron. Comparison of new and present coefficients; concerning the quality factor Q, particularly for neutron Q. New relations of protection and operational quantities; for field and individual monitoring. General conclusion of Publication 74. The Publication gives a certain direction for problems in evaluation of external exposure dose which have been discussed since the ICRP Fundamental Recommendation 1990 was issued. However, there still remain many problems especially in validity of the WR and of equation for Q-L relation. (K.H.)

  4. A novel coaxial Ku-band transit radiation oscillator without external guiding magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Junpu, E-mail: lingjunpu@163.com; Zhang, Jiande; He, Juntao; Jiang, Tao [College of Photoelectric Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2014-02-15

    A novel coaxial transit radiation oscillator without external guiding magnetic field is designed to generate high power microwave at Ku-band. By using a coaxial structure, the space-charge potential energy is suppressed significantly, that is good for enhancing efficient beam-wave interaction. In order to improve the transmission stability of the unmagnetized intense relativistic electron beam, a Pierce-like cathode is employed in the novel device. By contrast with conventional relativistic microwave generators, this kind of device has the advantages of high stability, non-guiding magnetic field, and high efficiency. Moreover, with the coaxial design, it is possible to improve the power-handing capacity by increasing the radial dimension of the Ku-band device. With a 550 keV and 7.5 kA electron beam, a 1.25 GW microwave pulse at 12.08 GHz has been obtained in the simulation. The power conversion efficiency is about 30%.

  5. Calculation of radiation and pair production probabilities at arbitrary incidence angles to crystal planes

    International Nuclear Information System (INIS)

    Tikhonirov, V.V.

    1993-01-01

    The results of calculations of the intensity and polarization of radiation from channeled and unchanneled e +- are presented. The Fourier transformation (FT) is used to calculate numerous matrix elements. The calculations for channeled e + showed fast approach of spectral intensity to its value calculated in the approximation of self-consistent field (ASCF) with growing photon energy. In the case of 150 GeV unchanneled e - in Ge at T=293 K the ASCF gives a significantly higher value as compared to the FT. 4 refs., 3 figs

  6. A method for calculating effective lifetime risk of radiation-induced cancer from screening mammography

    International Nuclear Information System (INIS)

    Ali, R.M.; England, A.; McEntee, M.F.; Hogg, P.

    2015-01-01

    Purpose: To propose a method for evaluating the effective lifetime risk of radiation-induced cancer from screening mammography and to present initial data for the UK National Breast Screening Programme. Material and methods: The imaging was undertaken using a Hologic Selenia full field digital mammographic unit. The proposed method utilises an ATOM phantom containing thermoluminescent dosimeters and a perspex-polyethylene breast phantom to measure organ doses during a standard four view screening mammogram. Effective dose was calculated and effective risk was modelled for a range of client ages. The total lifetime effective risk was then calculated for the UK national screening programme. Calculation of effective risk includes the radiation dose to examined and contralateral breasts in addition to other body organs; this is an advantage over the mean glandular dose. Results: The contralateral breast, thyroid, thymus, brain, lung, salivary glands, and bone marrow all receive more than 1 μGy radiation dose during screening mammography. A major difference exists for total effective lifetime risk of radiation-induced cancer between clients with average and high breast cancer risk. Differences are attributed to the commencement age of screening and time interval between screens. Conclusion: This study proposes a method to evaluate effective lifetime risk of radiation-induced cancer from screening mammography in order to compare different mammography screening programmes. - Highlights: • We proposed a method for the calculation of radiation-induced cancer from screening mammography. • We measured the radiation absorbed dose of different organs during screening mammography. • There are major differences between mammography screening programme categories with regard to radiation effective risk.

  7. Development of approximate shielding calculation method for high energy cosmic radiation on LEO satellites

    International Nuclear Information System (INIS)

    Sin, M. W.; Kim, M. H.

    2002-01-01

    To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values

  8. Development of approximate shielding calculation method for high energy cosmic radiation on LEO satellites

    Energy Technology Data Exchange (ETDEWEB)

    Sin, M. W.; Kim, M. H. [Kyunghee Univ., Yongin (Korea, Republic of)

    2002-10-01

    To calculate total dose effect on semi-conductor devices in satellite for a period of space mission effectively, two approximate calculation models for a comic radiation shielding were proposed. They are a sectoring method and a chord-length distribution method. When an approximate method was applied in this study, complex structure of satellite was described into multiple 1-dimensional slabs, structural materials were converted to reference material(aluminum), and the pre-calculated dose-depth conversion function was introduced to simplify the calculation process. Verification calculation was performed for orbit location and structure geometry of KITSAT-1 and compared with detailed 3-dimensional calculation results and experimental values. The calculation results from approximate method were estimated conservatively with acceptable error. However, results for satellite mission simulation were underestimated in total dose rate compared with experimental values.

  9. Contemporary Toxicity Profile of Breast Brachytherapy Versus External Beam Radiation After Lumpectomy for Breast Cancer

    International Nuclear Information System (INIS)

    Huo, Jinhai; Giordano, Sharon H.; Smith, Benjamin D.; Shaitelman, Simona F.; Smith, Grace L.

    2016-01-01

    Purpose: We compared toxicities after brachytherapy versus external beam radiation therapy (EBRT) in contemporary breast cancer patients. Methods and Materials: Using MarketScan healthcare claims, we identified 64,112 women treated from 2003 to 2012 with lumpectomy followed by radiation (brachytherapy vs EBRT). Brachytherapy was further classified by multichannel versus single-channel applicator approach. We identified the risks and predictors of 1-year infectious and noninfectious postoperative adverse events using logistic regression and temporal trends using Cochran-Armitage tests. We estimated the 5-year Kaplan-Meier cumulative incidence of radiation-associated adverse events. Results: A total of 4522 (7.1%) patients received brachytherapy (50.2% multichannel vs 48.7% single-channel applicator). The overall risk of infectious adverse events was higher after brachytherapy than after EBRT (odds ratio [OR] = 1.21; 95% confidence interval [CI] 1.09-1.34, P<.001). However, over time, the frequency of infectious adverse events after brachytherapy decreased, from 17.3% in 2003 to 11.6% in 2012, and was stable after EBRT at 9.7%. Beyond 2007, there were no longer excess infections with brachytherapy (P=.97). The overall risk of noninfectious adverse events was higher after brachytherapy than after EBRT (OR=2.27; 95% CI 2.09-2.47, P<.0001). Over time, the frequency of noninfectious adverse events detected increased: after multichannel brachytherapy, from 9.1% in 2004 to 18.9% in 2012 (Ptrend = .64); single-channel brachytherapy, from 12.8% to 29.8% (Ptrend<.001); and EBRT, from 6.1% to 10.3% (Ptrend<.0001). The risk was significantly higher with single-channel than with multichannel brachytherapy (hazard ratio = 1.32; 95% CI 1.03-1.69, P=.03). Of noninfectious adverse events, 70.9% were seroma. Seroma significantly increased breast pain risk (P<.0001). Patients with underlying diabetes, cardiovascular disease, and treatment with chemotherapy had increased

  10. Contemporary Toxicity Profile of Breast Brachytherapy Versus External Beam Radiation After Lumpectomy for Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Huo, Jinhai [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Giordano, Sharon H. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Benjamin D. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Shaitelman, Simona F. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Grace L., E-mail: glsmith@mdanderson.org [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2016-03-15

    Purpose: We compared toxicities after brachytherapy versus external beam radiation therapy (EBRT) in contemporary breast cancer patients. Methods and Materials: Using MarketScan healthcare claims, we identified 64,112 women treated from 2003 to 2012 with lumpectomy followed by radiation (brachytherapy vs EBRT). Brachytherapy was further classified by multichannel versus single-channel applicator approach. We identified the risks and predictors of 1-year infectious and noninfectious postoperative adverse events using logistic regression and temporal trends using Cochran-Armitage tests. We estimated the 5-year Kaplan-Meier cumulative incidence of radiation-associated adverse events. Results: A total of 4522 (7.1%) patients received brachytherapy (50.2% multichannel vs 48.7% single-channel applicator). The overall risk of infectious adverse events was higher after brachytherapy than after EBRT (odds ratio [OR] = 1.21; 95% confidence interval [CI] 1.09-1.34, P<.001). However, over time, the frequency of infectious adverse events after brachytherapy decreased, from 17.3% in 2003 to 11.6% in 2012, and was stable after EBRT at 9.7%. Beyond 2007, there were no longer excess infections with brachytherapy (P=.97). The overall risk of noninfectious adverse events was higher after brachytherapy than after EBRT (OR=2.27; 95% CI 2.09-2.47, P<.0001). Over time, the frequency of noninfectious adverse events detected increased: after multichannel brachytherapy, from 9.1% in 2004 to 18.9% in 2012 (Ptrend = .64); single-channel brachytherapy, from 12.8% to 29.8% (Ptrend<.001); and EBRT, from 6.1% to 10.3% (Ptrend<.0001). The risk was significantly higher with single-channel than with multichannel brachytherapy (hazard ratio = 1.32; 95% CI 1.03-1.69, P=.03). Of noninfectious adverse events, 70.9% were seroma. Seroma significantly increased breast pain risk (P<.0001). Patients with underlying diabetes, cardiovascular disease, and treatment with chemotherapy had increased

  11. On the contribution of external cost calculations to energy system governance: The case of a potential large-scale nuclear accident

    International Nuclear Information System (INIS)

    Laes, Erik; Meskens, Gaston; Sluijs, Jeroen P. van der

    2011-01-01

    The contribution of nuclear power to a sustainable energy future is a contested issue. This paper presents a critical review of an attempt to objectify this debate through the calculation of the external costs of a potential large-scale nuclear accident in the ExternE project. A careful dissection of the ExternE approach resulted in a list of 30 calculation steps and assumptions, from which the 6 most contentious ones were selected through a stakeholder internet survey. The policy robustness and relevance of these key assumptions were then assessed in a workshop using the concept of a 'pedigree of knowledge'. Overall, the workshop outcomes revealed the stakeholder and expert panel's scepticism about the assumptions made: generally these were considered not very plausible, subjected to disagreement, and to a large extent inspired by contextual factors. Such criticism indicates a limited validity and useability of the calculated nuclear accident externality as a trustworthy sustainability indicator. Furthermore, it is our contention that the ExternE project could benefit greatly - in terms of gaining public trust - from employing highly visible procedures of extended peer review such as the pedigree assessment applied to our specific case of the external costs of a potential large-scale nuclear accident. - Highlights: → Six most contentious assumptions were selected through a stakeholder internet survey. → Policy robustness of these assumptions was assessed in a pedigree assessment workshop. → Assumptions were considered implausible, controversial, and inspired by contextual factors. → This indicates a limited validity and useability as a trustworthy sustainability indicator.

  12. Light scattering by multiple spheres: comparison between Maxwell theory and radiative-transfer-theory calculations.

    Science.gov (United States)

    Voit, Florian; Schäfer, Jan; Kienle, Alwin

    2009-09-01

    We present a methodology to compare results of classical radiative transfer theory against exact solutions of Maxwell theory for a high number of spheres. We calculated light propagation in a cubic scattering region (20 x 20 x 20 microm(3)) consisting of different concentrations of polystyrene spheres in water (diameter 2 microm) by an analytical solution of Maxwell theory and by a numerical solution of radiative transfer theory. The relative deviation of differential as well as total scattering cross sections obtained by both approaches was evaluated for each sphere concentration. For the considered case, we found that deviations due to radiative transfer theory remain small, even for concentrations up to ca. 20 vol. %.

  13. Examinations on Applications of Manual Calculation Programs on Lung Cancer Radiation Therapy Using Analytical Anisotropic Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Min; Kim, Dae Sup; Hong, Dong Ki; Back, Geum Mun; Kwak, Jung Won [Dept. of Radiation Oncology, , Seoul (Korea, Republic of)

    2012-03-15

    There was a problem with using MU verification programs for the reasons that there were errors of MU when using MU verification programs based on Pencil Beam Convolution (PBC) Algorithm with radiation treatment plans around lung using Analytical Anisotropic Algorithm (AAA). On this study, we studied the methods that can verify the calculated treatment plans using AAA. Using Eclipse treatment planning system (Version 8.9, Varian, USA), for each 57 fields of 7 cases of Lung Stereotactic Body Radiation Therapy (SBRT), we have calculated using PBC and AAA with dose calculation algorithm. By developing MU of established plans, we compared and analyzed with MU of manual calculation programs. We have analyzed relationship between errors and 4 variables such as field size, lung path distance of radiation, Tumor path distance of radiation, effective depth that can affect on errors created from PBC algorithm and AAA using commonly used programs. Errors of PBC algorithm have showned 0.2{+-}1.0% and errors of AAA have showned 3.5{+-}2.8%. Moreover, as a result of analyzing 4 variables that can affect on errors, relationship in errors between lung path distance and MU, connection coefficient 0.648 (P=0.000) has been increased and we could calculate MU correction factor that is A.E=L.P 0.00903+0.02048 and as a result of replying for manual calculation program, errors of 3.5{+-}2.8% before the application has been decreased within 0.4{+-}2.0%. On this study, we have learned that errors from manual calculation program have been increased as lung path distance of radiation increases and we could verified MU of AAA with a simple method that is called MU correction factor.

  14. Examinations on Applications of Manual Calculation Programs on Lung Cancer Radiation Therapy Using Analytical Anisotropic Algorithm

    International Nuclear Information System (INIS)

    Kim, Jung Min; Kim, Dae Sup; Hong, Dong Ki; Back, Geum Mun; Kwak, Jung Won

    2012-01-01

    There was a problem with using MU verification programs for the reasons that there were errors of MU when using MU verification programs based on Pencil Beam Convolution (PBC) Algorithm with radiation treatment plans around lung using Analytical Anisotropic Algorithm (AAA). On this study, we studied the methods that can verify the calculated treatment plans using AAA. Using Eclipse treatment planning system (Version 8.9, Varian, USA), for each 57 fields of 7 cases of Lung Stereotactic Body Radiation Therapy (SBRT), we have calculated using PBC and AAA with dose calculation algorithm. By developing MU of established plans, we compared and analyzed with MU of manual calculation programs. We have analyzed relationship between errors and 4 variables such as field size, lung path distance of radiation, Tumor path distance of radiation, effective depth that can affect on errors created from PBC algorithm and AAA using commonly used programs. Errors of PBC algorithm have showned 0.2±1.0% and errors of AAA have showned 3.5±2.8%. Moreover, as a result of analyzing 4 variables that can affect on errors, relationship in errors between lung path distance and MU, connection coefficient 0.648 (P=0.000) has been increased and we could calculate MU correction factor that is A.E=L.P 0.00903+0.02048 and as a result of replying for manual calculation program, errors of 3.5±2.8% before the application has been decreased within 0.4±2.0%. On this study, we have learned that errors from manual calculation program have been increased as lung path distance of radiation increases and we could verified MU of AAA with a simple method that is called MU correction factor.

  15. Calculation of Smith-Purcell radiation from a volume strip grating

    International Nuclear Information System (INIS)

    Kube, G.

    2005-01-01

    Smith-Purcell radiation is generated by a charged particle beam passing close to the surface of a diffraction grating. Experimental investigations show a strong dependency of the emitted radiation intensity on the form of the grating profile. This influence is expressed by the radiation factor which is a measure of the grating efficiency, in close analogy to reflection coefficients of optical grating theories. The radiation factor depends on beam energy and observation geometry. Up to now calculations for radiation factors exist for lamellar, sinusoidal and echelette-type grating profiles. In this paper, calculations of Smith-Purcell radiation factors for volume strip gratings which are separated by vacuum gaps are presented. They are based on the modal expansion method and restricted to perfectly conducting grating surfaces and to electron trajectories perpendicular to the grating grooves. An infinite system of coupled linear algebraic equations for the scattered and the transmitted wave amplitudes is derived by imposing the continuity condition at the open end of the grooves, and by the boundary conditions at the remaining part of the interface. Numerical results are presented and discussed in view of using Smith-Purcell radiation for particle beam diagnostic purposes

  16. Observation and calculation of the solar radiation on the Tibetan Plateau

    International Nuclear Information System (INIS)

    Liu Jiandong; Liu Jingmiao; Linderholm, Hans W.; Chen Deliang; Yu Qiang; Wu Dingrong; Haginoya, Shigenori

    2012-01-01

    Highlights: ► Five years of continuous solar-radiation observations on the Tibetan Plateau were analyzed. ► Eight solar models were calibrated and validated in this highland region. ► A strategy for calculating solar radiation on the Tibetan Plateau was presented. - Abstract: Distribution of solar radiation is vital to locate the most suitable regions for harvesting solar energy, but solar radiation is only observed at few stations due to high costs and difficult maintenance. From 2001 to 2005, a set of pyranometer instruments were set up in Gaize, on the Tibetan Plateau, to test the hypothesis of high solar-radiation levels in this region, and find a suitable method for estimating the radiation. Over the 5-year observation period, the average daily radiation was 21 MJ m −2 day −1 with maximum daily values of 27 MJ m −2 day −1 occurring in June and minimum values of 14 MJ m −2 day −1 in December, which is much higher than those measured in other regions at similar latitudes. The observational data were used to validate a set of radiation models: five sunshine based and three temperature based. The results showed that of the five sunshine-based models, a newly developed “comprehensive” model performed the best, but that the “vapor revised Angstrom model” was recommended to use for its simplicity and easy operation. The temperature-based models performed worse than the sunshine-based ones, where the Wu model is to be preferred if a temperature-based model is the only option. Moreover, it was shown that when estimating the solar radiation based on time-dependent coefficients, consideration of the seasonal variation of the coefficients has little predictive value and is thus unnecessary. Based on the results of this study, a strategy for the calculation of solar radiation on the Tibetan Plateau was made for potential users.

  17. Calculation of radiation exposures from patients to whom radioactive materials have been administered

    International Nuclear Information System (INIS)

    McCormack, J.; Shearer, J.

    1998-01-01

    Spreadsheet templates have been developed by the authors to calculate radiation exposures to others from patients to whom radioactive materials have been administered (or, indeed, from any source of radiation exposure) to be readily calculated. The time during which contact should be avoided, along with the residual activity at resumption of contact is also calculated using an iterative technique. These spreadsheets allow a great deal of flexibility in the specification of clearance rates and close contact patterns for individual patients. Estimates of doses, restriction times and residual activities for 131 l thyrotoxic therapy, for various contact patterns and group of patients, were calculated. The spreadsheets are implemented using Microsoft EXCEL for both PC and Macintosh computers, and are readily available from the authors

  18. Incidence of primary hypothyroidism in patients exposed to therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland

    Directory of Open Access Journals (Sweden)

    B A Laway

    2012-01-01

    Full Text Available Introduction: Hypothyroidism is a known consequence of external-beam radiotherapy to the neck encompassing a part or whole of the thyroid gland. In this non-randomized prospective study, we have tried to evaluate the response of the thyroid gland to radiation by assessing thyroid function before irradiation and at regular intervals after irradiation. Aims and Objectives: The aim of this study were to assess in the cancer patients, who were exposed to the therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland: the incidence of primary hypothyroidism, the time required to become hypothyroid, any relation between the total dose for the development of hypothyroidism, and whether there are any patient or treatment-related factors that are predictive for the development of hypothyroidism, including the use of concurrent chemotherapy. Materials and Methods: This non-randomized, prospective study was conducted for a period of 2 years in which thyroid function was assessed in 59 patients (cases of head and neck cancer, breast cancer, lymphoma patients and other malignancies, who had received radiotherapy to the neck region. 59 euthyroid healthy patients (controls were also taken, who had not received the neck irradiation. These patients/controls were assessed periodically for 2 years. Results: The incidence of hypothyroidism after external beam radiation therapy (EBRT to neck where radiation portals include part or whole of the thyroid gland was 16.94%, seven cases had subclinical hypothyroidism (11.86% and three cases had clinical hypothyroidism (5.08%. Mean time for development of hypothyroidism was 4.5 months. There was no effect of age, gender, primary tumor site, radiation dose and chemotherapy, whether neoadjuvant or concurrent with the development of hypothyroidism. Conclusion: In summary, we found that thyroid dysfunction is a prevalent, yet easily treatable source of morbidity in patients

  19. Cost-effectiveness of radiotherapy during surgery compared with external radiation therapy in the treatment of women with breast cancer

    Directory of Open Access Journals (Sweden)

    Hedie Mosalanezhad

    2016-04-01

    Full Text Available Introduction: Intraoperative radiation therapy device (IORT is one of the several options for partial breast irradiation. IORT is sent to the tumor bed during surgery and can be replaced with conventional standard therapy (EBRT. The aim of this study was to evaluate the safety and effectiveness of IORT machine compared with EBRT and to determine the dominant option in terms of the cost-effectiveness. Method: This study was conducted in two phases; the first phase was a comprehensive review of the electronic databases search that was extracted after extraction and selection of the articles used in this article on effectiveness outcomes. Data collection form was completed by professionals and experts to estimate the cost of treatment, intraoperative radiotherapy and radiotherapy cost when using external radiation therapy process; direct costs were considered from the perspective of service provider and they were calculated in the second phase to determine the option of cost-effective ICER. Excel software was used for data analysis and sensitivity analysis was performed to determine the strength of the results of cost-effectiveness. Results:18 studies were selected but only 8 of them were shown to have acceptable quality. The consequences like “rate of cancer recurrence”, “seroma”, “necrosis”, “toxic”, “skin disorders and delayed wound healing” and “spread the pain” were among the consequences used in the selected articles. The total costs for each patient during a course of treatment for EBRT and IORT were estimated 1398 and $5337.5, respectively. During the analysis, cost-effectiveness of the consequences of cancer recurrence, seroma, necrosis and skin disorders and delayed wound healing ICER was calculated. And IORT was found to be the dominant supplier in all cases. Also, in terms of implications of toxicity and prevalence of pain, IORT had a lower cost and better effectiveness and consequently the result was more cost

  20. Thyroid cancer in the Marshallese: relative risk of short-lived internal emitters and external radiation exposure

    International Nuclear Information System (INIS)

    Lessard, E.T.; Brill, A.B.; Adams, W.H.

    1985-01-01

    In a study of the comparative effects of internal versus external irradiation of the thyroid in young people, we determined that the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times less thyroid cancer than did the same dose of radiation given externally. We determined this finding for a group of 85 Marshall Islands children, who were less than 10 years of age at the time of exposure and who were accidentially exposed to internal and external thyroid radiation at an average level of 1400 rad. The external risk coefficient ranged between 2.5 and 4.9 cancers per million person-rad-years at risk, and thus, from our computations, the internal risk coefficient for the Marshallese children was estimated to range between 1.0 and 1.4 cancers per million person-rad-years at risk. In contrast, for individual more than 10 years of age at the time of exposure, the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times more thyroid cancer than did the same dose of radiation given externally. The external risk coefficients for the older age groups were reported in the literature to be in the range of 1.0 to 3.3 cancers per million person-rad-years-at risk. We computed internal risk coefficients of 3.3 to 8.1 cancers per million person-rad-years at risk for adolescent and adult groups. This higher sensitivity to cancer induction in the exposed adolescents and adults, is different from that seen in other exposed groups. 14 refs., 8 tabs

  1. Thyroid cancer in the Marshallese: relative risk of short-lived internal emitters and external radiation exposure

    International Nuclear Information System (INIS)

    Lessard, E.T.; Brill, A.B.; Adams, W.H.

    1986-01-01

    In a study of the comparative effects of internal versus external irradiation of the thyroid in young people, we determined that the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times less thyroid cancer than did the same dose of radiation given externally. The authors determined this finding for a group of 85 Marshall Islands children, who were less than 10 years of age at the time of exposure and who were accidentally exposed to internal and external thyroid radiation at an average level of 1400 rad. The external risk coefficient ranged between 2.5 and 4.9 cancers per million person-rad-years at risk, and thus, from our computations, the internal risk coefficient for the Marshallese children was estimated to range between 1.0 and 1.4 cancers per million person-rad-years at risk. In contrast, for individuals more than 10 years of age at the time of exposure, the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times more thyroid cancer than did the same dose of radiation given externally. The external risk coefficients for the older age groups were reported in the above literature to be in the range of 1.0 to 3.3 cancers per million person-rad-years-at risk. The authors computed internal risk coefficients of 3.3 to 8.1 cancers per million person-rad-years at risk for adolescent and adult groups. This higher sensitivity to cancer induction in the exposed adolescents and adults, is different from that seen in other exposed groups. The small number of cancers in the exposed population and the influence of increased levels of TSH, nonuniform irradiation of the thyroid, and thyroid cell killing at high dose make it difficult to draw firm conclusions from these studies. 14 references, 8 tables

  2. Adaptive Radiation Therapy for Postprostatectomy Patients Using Real-Time Electromagnetic Target Motion Tracking During External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Mingyao [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States); Bharat, Shyam [Philips Research North America, Briarcliff Manor, New York (United States); Michalski, Jeff M.; Gay, Hiram A. [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States); Hou, Wei-Hsien [St Louis University School of Medicine, St Louis, Missouri (United States); Parikh, Parag J., E-mail: pparikh@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, Saint Louis, Missouri (United States)

    2013-03-15

    Purpose: Using real-time electromagnetic (EM) transponder tracking data recorded by the Calypso 4D Localization System, we report inter- and intrafractional target motion of the prostate bed, describe a strategy to evaluate treatment adequacy in postprostatectomy patients receiving intensity modulated radiation therapy (IMRT), and propose an adaptive workflow. Methods and Materials: Tracking data recorded by Calypso EM transponders was analyzed for postprostatectomy patients that underwent step-and-shoot IMRT. Rigid target motion parameters during beam delivery were calculated from recorded transponder positions in 16 patients with rigid transponder geometry. The delivered doses to the clinical target volume (CTV) were estimated from the planned dose matrix and the target motion for the first 3, 5, 10, and all fractions. Treatment adequacy was determined by comparing the delivered minimum dose (D{sub min}) with the planned D{sub min} to the CTV. Treatments were considered adequate if the delivered CTV D{sub min} is at least 95% of the planned CTV D{sub min}. Results: Translational target motion was minimal for all 16 patients (mean: 0.02 cm; range: −0.12 cm to 0.07 cm). Rotational motion was patient-specific, and maximum pitch, yaw, and roll were 12.2, 4.1, and 10.5°, respectively. We observed inadequate treatments in 5 patients. In these treatments, we observed greater target rotations along with large distances between the CTV centroid and transponder centroid. The treatment adequacy from the initial 10 fractions successfully predicted the overall adequacy in 4 of 5 inadequate treatments and 10 of 11 adequate treatments. Conclusion: Target rotational motion could cause underdosage to partial volume of the postprostatectomy targets. Our adaptive treatment strategy is applicable to post-prostatectomy patients receiving IMRT to evaluate and improve radiation therapy delivery.

  3. The correlation schemes in calculations of the rate constants of some radiation chemical reactions

    International Nuclear Information System (INIS)

    Zagorets, P.A.; Shostenko, A.G.; Kim, V.

    1983-01-01

    The various correlation relationships of the evaluation of the rate constants of radiation chemical reactions of addition, abstraction and isomerization were considered. It was shown that neglection of the influence of solvent can result in errors in calculations of rate constants equalling two orders in magnitude. Several examples of isokinetic relationship are given. The methods of calculation of transmission coefficient of reaction addition have been discussed. (author)

  4. Efficacy of external fractionated radiation therapy in the treatment of meningiomas: a 20-year experience

    International Nuclear Information System (INIS)

    Pourel, Nicolas; Auque, Jean; Bracard, Serge; Hoffstetter, Sylvette; Luporsi, Elisabeth; Vignaud, Jean-Michek; Bey, Pierre

    2001-01-01

    Background: This is a retrospective analysis of a series of meningiomas treated by radiotherapy. Materials and methods: From 1978 to 1997, 45 patients with intracranial meningiomas were referred for external fractionated radiotherapy at Centre Alexis Vautrin. All patients were given 50-70 Gy to the tumor bed (median: 56 Gy), 1.8-2 Gy per fraction. Results: Evaluation was performed in June 1999 using the Kaplan-Meyer actuarial method with a median follow-up of 30 months (range: 1-166), relapse-free survivals (RFSs) were 75% at 5 years and 67% at 8 years; overall survival (OS) was 74% at 5 and 8 years. For the 26 benign histologically documented lesions, RFSs were 95% at 5 years and 81% at 8 years; OS was 85% at 5 and 8 years. One major radiation-induced complication occurred in this series (decline of cognitive function). According to the indication of radiotherapy, we divided the series into four groups: postoperative irradiation after a first subtotal resection (11 patients), 5-year RFS was 90%; after first recurrence (±salvage surgery, 14 patients), 73%; after further recurrence (±salvage surgery, 11 patients), 67%; as exclusive treatment (nine patients), 80%. Atypical and malignant lesions (n=7) all relapsed before 24 months of follow-up, all patients but one died before 42 months. Age at the time of irradiation (≥60 vs. <60 years) and radiotherapy dose (≥60 vs. <60 Gy) did not influence local control or OS. Atypical and malignant lesions (WHO grades II and III) meningiomas had a worse outcome than benign lesions (WHO grade I, P<0.01). Conclusions: These results compare favorably with previously published data. External fractionated radiotherapy is well tolerated and effective. There is still a debate about the place of radiotherapy in the treatment of meningiomas: after subtotal resection, should radiotherapy be given postoperatively or at the time of progression? Should radiotherapy replace surgery when the risk of postoperative sequellae is high

  5. Evaluation of personal dose equivalent 'HP(d)' in a external individual monitoring system for X and gamma radiation

    International Nuclear Information System (INIS)

    Santoro, C.; Antonio Filho, J.; Santos, M.A.P.

    2007-01-01

    The good of individual monitoring for external radiation is the assessment of occupational exposure from X and γ radiations in order to assure that the radiological conditions of the workplace are acceptable, safe and satisfactory. The evaluation of radiations doses for workers must not exceed dose limits specified for workers, according to national regulatory agencies. Nowadays, there are two external monitoring systems in use, both based on ICRU definitions. In the conventional system, the workers doses are evaluated in terms of Hx. The personal dosimeter is worn over chest surface and it is calibrated in function of air kerma. In the new system, the workers doses are evaluated in terms of HP(d) and the personal dosimeter is calibrated in function of phantom doses. The aim of this paper is to adapt an external dosimetry laboratory (based on photographic dosimetry) to evaluate the personal dosimeters in terms of HP(d). In this way, a simple methodology, based on linear programming, was utilized. In this adaptation, calibration curves were obtained for radiation qualities (W and N series) described by International Organization for Standardization (ISO 4037-1, 1995). These calibration curves offer a better accuracy on dose determinations and energy below 140 keV, improving the quality of service rendered the society. (author)

  6. Survey and evaluation of the external research and development programme 1977-1983 of the Swedish Radiation Protection Institute

    International Nuclear Information System (INIS)

    Persson, Lars.

    1993-01-01

    A review of the external research programme of SSI is undertaken. The main research programme is in this report divided into five subprogrammes according to the main programmes of the Institute. This report covers research projects reported 1977-1983. An evaluation of the impact of the R and D programme is included in the report. The external R and D research programme of SSI has had an important impact on the radiation protection work in Sweden. The methods for evaluation of research programmes are also discussed in the report

  7. Calculation and interpretation of In-Situ measurements of initial radiations at Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Loewe, W.E.

    1983-01-01

    Cobalt activation calculations will be reviewed, and similar comparisons of sulfur activation interior to electrical insulators on power transmission lines will be discussed. The relationship between neutron tissue kermas one to two kilometers from hypocenter and the particular activations of cobalt and sulfur are reviewed. At present, measured and calculated quantities agree within associated uncertainties, which are substantial. Additional work to shrink these uncertainties will be discussed. Particular cobalt activation topics will include: the sensitivity to thermal neutrons outside the pillar; calculated values using actual Nagasaki concrete composition; and calculational advances to improve modelling of the actual configuration. Particular sulfur activation topics will include: absolute comparisons of measured and calculated ratios of dpm/gm of 32 P at all measured ranges, based on approximate experimental values for insulator attentuation and source radiations; the relationship between sulfur activation within a kilometer of hypocenter and kermas at two kilometers; and calculational advances to improve modelling of the actual configuration

  8. Radionuclide mobility in soils and its effect on the external radiation exposure

    International Nuclear Information System (INIS)

    Bunzl, K.; Hillmann, U.; Jacob, P.; Kretner, R.; Schimmack, W.; Tikhomirov, F.; Scheglov, A.; Arkhipov, N.P.; Arkhipov, A.N.; Alexakhin, R.M.; Kruglov, S.V.; Loschilov, N.; Ivanov, Y.; Levchuk, S.; Kashparov, V.; Oreshich, L.

    1996-01-01

    In order to predict the gamma-dose rate of 137 Cs for a period of about 100 years after the Chernobyl accident, the present vertical distribution of radiocesium in several meadow soils in the Chernobyl area and in Germany was determined and the corresponding residence half-times of this radionuclide in the various soil layers were evaluated with a compartment model. The resulting residence half-times were subsequently used to calculate the vertical distribution of 137 Cs in the soil as a function of time and finally to predict the external gamma-dose rates in air for these sites at various times. The results show that the time dependence of the relative gamma-dose rate in air D/D t=0 at both sites can be described by a two-term exponential equation. At a given time, the relative gamma-dose rate at the Chernobyl sites is always higher as compared to the German sites. This difference is the result of the slower vertical migration of 137 Cs at the Chernobyl sites

  9. Adjuvant external beam radiation therapy with concurrent chemotherapy in the management of gallbladder carcinoma

    International Nuclear Information System (INIS)

    Kresl, John J.; Schild, Steven E.; Henning, George T.; Gunderson, Leonard L.; Donohue, John; Pitot, Henry; Haddock, Michael G.; Nagorney, David

    2002-01-01

    Purpose: This study was performed to evaluate the outcome of patients with gallbladder cancer who received postoperative concurrent chemotherapy and radiation therapy. Methods and Materials: Curative resection followed by adjuvant combined modality therapy with external beam radiation therapy (EBRT) and chemotherapy was attempted in 21 consecutive gallbladder carcinoma (GBC) patients at the Mayo Clinic from 1985 through 1997. All patients received concurrent 5-fluorouracil during EBRT. EBRT fields encompassed the tumor bed and regional lymph nodes (median dose of 54 Gy in 1.8-2.0-Gy fractions). One patient received 15 Gy intraoperatively after EBRT. A retrospective analysis was performed for the end points of local control, distant failure, and overall survival. Results: After maximal resection, 12 patients had no residual disease on pathologic evaluation, 5 had microscopic residual disease, and 4 had gross residual disease. One patient had Stage I disease, and 20 had Stage III-IV disease. With median follow-up of 5 years (range: 2.6-11.5 years), 5-year survival for the entire cohort was 33%. The 5-year survival rate of patients with Stage I-III disease was 65% vs. 0% for those with Stage IV disease (p 54 Gy (microscopic residual, 3 patients; gross residual, 1 patient; negative but narrow margins, 2 patients) vs. 65% for the 15 who received a lower dose (3, gross residual; 2, microresidual; 10, negative margins). Conclusion: Patients with completely resected (negative margins) GBC followed by adjuvant EBRT plus 5-fluorouracil chemotherapy had a relatively favorable prognosis, with a 5-year survival rate of 64%. These results seem to be superior to historical surgical controls from the Mayo Clinic and other institutions, which report 5-year survival rates of approximately 33% with complete resection alone. Both tumor stage and extent of resection seemed to influence survival and local control. More aggressive measures using current cancer therapies and integration

  10. Gene expression analysis in rice plants after external radiation exposure in Iitate village

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, G.; Fukumoto, M. [Institute of Development, Aging and Cancer, Tohoku University (Japan); Imanaka, T. [Research Reactor Institute, Kyoto University (Japan); Shibato, J. [Department of Anatomy I, School of Medicine, Showa University (Japan); Kubo, A. [Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies (Japan); Kikuchi, S. [Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences (Japan); Rakwal, R. [Organization for Educational Initiatives, University of Tsukuba (Japan)

    2014-07-01

    Rice plants exposed to radiation respond to the stress by activating self-defense mechanisms. A well-established molecular approach to measure stress is by cataloging global gene expression profiles. Here, we examined the effect of radiation exposure in a cereal crop model plant - rice (Oryza sativa L.) cultivar Nipponbare - in the village of Iitate of Fukushima prefecture. Iitate village is a highly radio-contaminated site due to the Fukushima Daiichi nuclear power plant accident following the Great East Japan Earthquake. The experimental approach comprised of five steps. First, healthy rice seedlings were grown in the greenhouse facility at National Institute for Environmental Sciences. Post-germination at 30 deg. C similarly germinated seeds were placed in neat rows in seedling pots having commercial soil (JA Zen-Noh, Japan; http//www.zennoh.or.jp/) with recommended NPK (nitrogen, phosphorus, and potash) doses at a controlled (25 deg. C, 70% relative humidity and natural light condition) greenhouse. Second, the seedlings were transported from a controlled greenhouse in Tsukuba to Iitate Farm (ITF) and placed, with no direct contact with soil, in a low-level gamma field where the rate of Cs-137 was 700 kBq/m{sup 2}. Third, exposure periods were set at 6, 12, 24, 48, and 72 h after arrival at ITF, and rice leaves at the 3. position (from the base) from 6 to 10 seedlings were sampled in dry ice. As control, rice leaves were sampled at the start in Tsukuba and immediately at arrival upon ITF; to know the radiation levels during growth and transport of the rice to ITF, accumulated radiation dose was calculated using a MYDOSE mini electronic pocket dosimeter (model PDM-222-52, ALOKA, Japan). A sample set was also taken at 72 h from healthy rice seedlings in the greenhouse at Tsukuba. All samples were stored at -80 deg. C. Accumulated total dose for exposed rice seedlings at 72 h was 200 mSv. Fourth, gene expression analysis was initiated by grinding the leaves to a

  11. Intercomparison of radiative forcing calculations of stratospheric water vapour and contrails

    Energy Technology Data Exchange (ETDEWEB)

    Myhre, Gunnar [Dept. of Geosciences, Univ. of Oslo (Norway); Center for International Climate and Environmental Research-Oslo (CICERO), Oslo (Norway); Kvalevaag, Maria [Dept. of Geosciences, Univ. of Oslo (Norway); Raedel, Gaby; Cook, Jolene; Shine, Keith P. [Dept. of Meteorology, Univ. of Reading (United Kingdom); Clark, Hannah [CNRM/GAME Meteo France, Toulouse (France); Lab. d' Aerologie, Univ. de Toulouse (France); Karcher, Fernand [CNRM/GAME Meteo France, Toulouse (France); Markowicz, Krzysztof; Kardas, Aleksandra; Wolkenberg, Paulina [Inst. of Geophysics, Univ. of Warsaw (Poland); Balkanski, Yves [LSCE/IPSL, Lab. CEA-CNRS-UVSQ (France); Ponater, Michael [Deutsches Zentrum fuer Luft und Raumfahrt (DLR), Inst. fuer Physik der Atmosphaere, Oberpfaffenhofen (Germany); Forster, Piers; Rap, Alexandru [School of Earth and Environment, Univ. of Leeds (United Kingdom); Leon, Ruben Rodriguez de [Manchester Metropolitan Univ. (United Kingdom)

    2009-12-15

    Seven groups have participated in an intercomparison study of calculations of radiative forcing (RF) due to stratospheric water vapour (SWV) and contrails. a combination of detailed radiative transfer schemes and codes for global-scale calculations have been used, as well as a combination of idealized simulations and more realistic global-scale changes in stratospheric water vapour and contrails. Detailed line-by-line codes agree within about 15% for longwave (LW) and shortwave (SW) RF, except in one case where the difference is 30%. Since the LW and SW RF due to contrails and SWV changes are of opposite sign, the differences between the models seen in the individual LW and SW components can be either compensated or strengthened in the net RF. and thus in relative terms uncertainties are much larger for the net RF. Some of the models used for global-scale simulations of changes in SWV and contrails differ substantially in RF from the more detailed radiative transfer schemes. For the global-scale calculations we use a method of weighting the results to calculate a best estimate based on their performance compared to the more detailed radiative transfer schemes in the idealized simulations. (orig.)

  12. Calculation of radiation heat generation on a graphite reflector side of IAN-R1 Reactor

    International Nuclear Information System (INIS)

    Duque O, J.; Velez A, L.H.

    1987-01-01

    Calculation methods for radiation heat generation in nuclear reactor, based on the point kernel approach are revisited and applied to the graphite reflector of IAN-R1 reactor. A Fortran computer program was written for the determination of total heat generation in the reflector, taking 1155 point in it

  13. Model-Independent Calculation of Radiative Neutron Capture on Lithium-7

    NARCIS (Netherlands)

    Rupak, Gautam; Higa, Renato

    2011-01-01

    The radiative neutron capture on lithium-7 is calculated model independently using a low-energy halo effective field theory. The cross section is expressed in terms of scattering parameters directly related to the S-matrix elements. It depends on the poorly known p-wave effective range parameter

  14. Calculation of radiation loss of 1. 2 GeV-electrons in a thick silicon monocrystal

    Energy Technology Data Exchange (ETDEWEB)

    Keshtova, S.V.; Komarov, F.F.; Telegin, V.I.

    1988-10-01

    The angular distribution of radiation loss of different fractions of 1.2 GeV-electrons during axial channeling in a Si monocrystal of 1.6 mm thickness is discussed. The results of the numerical calculations are compared with the experimental data.

  15. Process of cross section generation for radiation shielding calculations, using the NJOY code

    International Nuclear Information System (INIS)

    Ono, S.; Corcuera, R.P.

    1986-10-01

    The process of multigroup cross sections generation for radiation shielding calculations, using the NJOY code, is explained. Photon production cross sections, processed by the GROUPR module, and photon interaction cross sections processed by the GAMINR are given. These data are compared with the data produced by the AMPX system and published data. (author) [pt

  16. The Effect of External Radiation Therapy in management of malignant obstructive Jaundice due to Porta Hepatis metastasis from Stomach Cancer

    International Nuclear Information System (INIS)

    Yang, Kwang Mo; Kim, Joon Hee; Kim, Chul Soo; Suh, Hyun Suk; Kim, Re Hwe

    1995-01-01

    Purpose : Since 1983, authors have conducted a study to evaluate the effect of external radiation therapy an to determine affected factors in management of the patients with malignant obstructive jaundice due to porta hepatis metastasis from stomach cancer. Materials and methods : Thirty two patients with malignant obstructive jaundice due to porta hepatis metastasis from gastric cancer were presented. We have analysed 23 patients who were treated with external radiation therapy of more than 3000 cGy. The radiation dose, disease extent at development of jaundice, total bilirubin levels before radiation therapy, differentiation of histology, combined treatment, intent of primary surgery, initial stage of gastric cancer were analyzed to determine affected factors in radiation therapy. External radiation therapy was delivered with a daily dose of 180-300 cGy. 5 times a week fractionation using 4 MeV linear accelerator. The radiation field included the porta hepatis with tumor mass by the abdominal ultrasonography or CT scan. In twenty three patients received more than 3000 cGy, total irradiation dose was ranged from 3000 cGy to 5480 cGy, median 3770 cGy. Among 23 patients, 13 patients were delivered more than equivalent dose of TDF 65(4140 cGy/23fx). Results : Among 23 patients, complete, partial and no response were observed in 13, 5, 5 patients, respectively. The median survival for all patients was 5 months. He significant prolongation of median survival was observed in complete responders(11 months) as compared to partial and no responders(5 months, 5 months, respectively). Out of 13 patients with complete response, 6 patients lived more than a year. Among 13 patients received more than 4140 cGy equivalent dose, complete, partial and no response were observed in 10, 2 and 1 patients, respectively. The median survival for all these patients was 9.5 months. The median survival for complete responders(10/13) was 11.5 months. Among 10 patients receiving less than 4140

  17. Hormonal therapy with external radiation therapy for metastatic spinal cord compression from newly diagnosed prostate cancer

    International Nuclear Information System (INIS)

    Kato, So; Hozumi, Takahiro; Yamakawa, Kiyofumi; Higashikawa, Akiro; Goto, Takahiro; Shinohara, Mitsuru; Kondo, Taiji

    2013-01-01

    Although hormonal therapy is effective for treatment of prostate cancer, its effect in the treatment of metastatic spinal cord compression (MSCC) has not been established. The objective of this study was to clarify the efficacy of conservative treatment of MSCC-induced paralysis resulting from prostate cancer for patients without a previous treatment history. We reviewed data from 38 patients with MSCC-induced paralysis from newly diagnosed prostate cancer who presented to our service between 1984 and 2010. Conservative treatment consisted of hormonal therapy with external radiation therapy (ERT). Patient demographic data, treatment details, involved spine MRI images, complications, and the course of neurologic recovery were investigated. Twenty-five patients were treated conservatively. Mean follow-up period was 36.8 months. Sixteen patients (two with Frankel B, 14 with Frankel C) were unable to walk at initial presentation. After initiating conservative treatment, 75% (12 of 16) of these patients regained the ability to walk within 1 month, 88% (14 in 16) did so within 3 months, and all non-ambulatory patients did so within 6 months. No one had morbid complications. Four patients who did not regain the ability to walk at 1 month were found to have progressed to paraplegia rapidly, and tended to have severe compression as visualized on MRI, with a delay in the start of treatment in comparison with those who did so within 1 month (21.0 vs. 7.8 days). Hormonal therapy associated with ERT is an important option for treatment of MSCC resulting from newly diagnosed prostate cancer. (author)

  18. Hormonal changes after localized prostate cancer treatment. Comparison between external beam radiation therapy and radical prostatectomy.

    Science.gov (United States)

    Planas, J; Celma, A; Placer, J; Maldonado, X; Trilla, E; Salvador, C; Lorente, D; Regis, L; Cuadras, M; Carles, J; Morote, J

    2016-11-01

    To determine the influence of radical prostatectomy (RP) and external beam radiation therapy (EBRT) on the hypothalamic pituitary axis of 120 men with clinically localized prostate cancer treated with RP or EBRT exclusively. 120 patients with localized prostate cancer were enrolled. Ninety two patients underwent RP and 28 patients EBRT exclusively. We measured serum levels of luteinizing hormone, follicle stimulating hormone (FSH), total testosterone (T), free testosterone, and estradiol at baseline and at 3 and 12 months after treatment completion. Patients undergoing RP were younger and presented a higher prostate volume (64.3 vs. 71.1 years, p<0.0001 and 55.1 vs. 36.5 g, p<0.0001; respectively). No differences regarding serum hormonal levels were found at baseline. Luteinizing hormone and FSH levels were significantly higher in those patients treated with EBRT at three months (luteinizing hormone 8,54 vs. 4,76 U/l, FSH 22,96 vs. 8,18 U/l, p<0,0001) while T and free testosterone levels were significantly lower (T 360,3 vs. 414,83ng/dl, p 0,039; free testosterone 5,94 vs. 7,5pg/ml, p 0,018). At 12 months FSH levels remained significantly higher in patients treated with EBRT compared to patients treated with RP (21,01 vs. 8,51 U/l, p<0,001) while T levels remained significantly lower (339,89 vs. 402,39ng/dl, p 0,03). Prostate cancer treatment influences the hypothalamic pituitary axis. This influence seems to be more important when patients with prostate cancer are treated with EBRT rather than RP. More studies are needed to elucidate the role that prostate may play as an endocrine organ. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Radiation safety assessment of cobalt 60 external beam radiotherapy using the risk-matrix method

    International Nuclear Information System (INIS)

    Dumenigo, C; Vilaragut, J.J.; Ferro, R.; Guillen, A.; Ramirez, M.L.; Ortiz Lopez, P.; Rodriguez, M.; McDonnell, J.D.; Papadopulos, S.; Pereira, P.P.; Goncalvez, M.; Morales, J.; Larrinaga, E.; Lopez Morones, R.; Sanchez, R.; Delgado, J.M.; Sanchez, C.; Somoano, F.

    2008-01-01

    External beam radiotherapy is the only practice in which humans are placed directly in a radiation beam with the intention to deliver a very high dose. This is why safety in radiotherapy is very critical, and is a matter of interest to both radiotherapy departments and regulatory bodies. Accidental exposures have occurred throughout the world, thus showing the need for systematic safety assessments, capable to identify preventive measures and to minimize consequences of accidental exposure. Risk-matrix is a systematic approach which combines the relevant event features to assess the overall risk of each particular event. Once an event sequence is identified, questions such as how frequent the event, how severe the potential consequences and how reliable the existing safety measures are answered in a risk-matrix table. The ultimate goal is to achieve that the overall risk for events with severe consequences should always be low o very low. In the present study, the risk-matrix method has been applied to an hypothetical radiotherapy department, which could be equivalent to an upper level hospital of the Ibero American region, in terms of safety checks and preventive measures. The application of the method has identified 76 event sequences and revealed that the hypothetical radiotherapy department is sufficiently protected (low risk) against them, including 23 event sequences with severe consequences. The method has revealed that the risk of these sequences could grow to high level if certain specific preventive measures were degraded with time. This study has identified these preventive measures, thus facilitating a rational allocation of resources in regular controls to detect any loss of reliability. The method has proven to have an important practical value and is affordable at hospital level. The elaborated risk-matrix can be easily adapted to local circumstances, in terms of existing controls and safety measures. This approach can help hospitals to identify

  20. Radiation skyshine calculation with MARS15 for the Mu2e Experiment at Fermilab

    International Nuclear Information System (INIS)

    Leveling, A.F.

    2015-01-01

    The Fermilab Antiproton source is to be re-purposed to provide an 8 kW proton beam to the Mu2e experiment by 1/3 integer, slow resonant extraction. Shielding provided by the existing facility must be supplemented with in-tunnel shielding to limit the radiation effective dose rate above the shield in the AP30 service building. In addition to the nominal radiation shield calculations, radiation skyshine calculations were required to ensure compliance with Fermilab Radiological Controls Manual. A complete model of the slow resonant extraction system including magnets, electrostatic septa, magnetic fields, tunnel enclosure with shield, and a nearby exit stairway are included in the model. The skyshine model extends above the beam enclosure surface to 10 km vertically and 5 km radially. (authors)

  1. Treatment planning systems for external whole brain radiation therapy: With and without MLC (multi leaf collimator) optimization

    Science.gov (United States)

    Budiyono, T.; Budi, W. S.; Hidayanto, E.

    2016-03-01

    Radiation therapy for brain malignancy is done by giving a dose of radiation to a whole volume of the brain (WBRT) followed by a booster at the primary tumor with more advanced techniques. Two external radiation fields given from the right and left side. Because the shape of the head, there will be an unavoidable hotspot radiation dose of greater than 107%. This study aims to optimize planning of radiation therapy using field in field multi-leaf collimator technique. A study of 15 WBRT samples with CT slices is done by adding some segments of radiation in each field of radiation and delivering appropriate dose weighting using a TPS precise plan Elekta R 2.15. Results showed that this optimization a more homogeneous radiation on CTV target volume, lower dose in healthy tissue, and reduced hotspots in CTV target volume. Comparison results of field in field multi segmented MLC technique with standard conventional technique for WBRT are: higher average minimum dose (77.25% ± 0:47%) vs (60% ± 3:35%); lower average maximum dose (110.27% ± 0.26%) vs (114.53% ± 1.56%); lower hotspot volume (5.71% vs 27.43%); and lower dose on eye lenses (right eye: 9.52% vs 18.20%); (left eye: 8.60% vs 16.53%).

  2. Treatment planning systems for external whole brain radiation therapy: With and without MLC (multi leaf collimator) optimization

    International Nuclear Information System (INIS)

    Budiyono, T; Budi, W S; Hidayanto, E

    2016-01-01

    Radiation therapy for brain malignancy is done by giving a dose of radiation to a whole volume of the brain (WBRT) followed by a booster at the primary tumor with more advanced techniques. Two external radiation fields given from the right and left side. Because the shape of the head, there will be an unavoidable hotspot radiation dose of greater than 107%. This study aims to optimize planning of radiation therapy using field in field multi-leaf collimator technique. A study of 15 WBRT samples with CT slices is done by adding some segments of radiation in each field of radiation and delivering appropriate dose weighting using a TPS precise plan Elekta R 2.15. Results showed that this optimization a more homogeneous radiation on CTV target volume, lower dose in healthy tissue, and reduced hotspots in CTV target volume. Comparison results of field in field multi segmented MLC technique with standard conventional technique for WBRT are: higher average minimum dose (77.25% ± 0:47%) vs (60% ± 3:35%); lower average maximum dose (110.27% ± 0.26%) vs (114.53% ± 1.56%); lower hotspot volume (5.71% vs 27.43%); and lower dose on eye lenses (right eye: 9.52% vs 18.20%); (left eye: 8.60% vs 16.53%). (paper)

  3. Numerical calculation of acoustic radiation from band-vibrating structures via FEM/FAQP method

    Directory of Open Access Journals (Sweden)

    GAO Honglin

    2017-08-01

    Full Text Available The Finite Element Method (FEM combined with the Frequency Averaged Quadratic Pressure method (FAQP are used to calculate the acoustic radiation of structures excited in the frequency band. The surface particle velocity of stiffened cylindrical shells under frequency band excitation is calculated using finite element software, the normal vibration velocity is converted from the surface particle velocity to calculate the average energy source (frequency averaged across intensity, frequency averaged across pressure and frequency averaged across velocity, and the FAQP method is used to calculate the average sound pressure level within the bandwidth. The average sound pressure levels are then compared with the bandwidth using finite element and boundary element software, and the results show that FEM combined with FAQP is more suitable for high frequencies and can be used to calculate the average sound pressure level in the 1/3 octave band with good stability, presenting an alternative to applying frequency-by-frequency calculation and the average frequency process. The FEM/FAQP method can be used as a prediction method for calculating acoustic radiation while taking the randomness of vibration at medium and high frequencies into consideration.

  4. Phase II Radiation therapy oncology group trial of weekly paclitaxel and conventional external beam radiation therapy for supratentorial glioblastoma multiforme

    International Nuclear Information System (INIS)

    Langer, Corey J.; Ruffer, James; Rhodes, Harker; Paulus, Rebecca; Murray, Kevin; Movsas, Benjamin; Curran, Walter

    2001-01-01

    Purpose: Fractionated external beam radiotherapy (EBRT) ± carmustine (BCNU) is the standard of care for patients with glioblastoma multiforme (GBM), but survival results remain poor. Preclinical studies indicate synergy between RT and paclitaxel (TAX) in astrocytoma cell lines. Phase I studies in GBM have demonstrated a maximum tolerated dose for TAX of 225 mg/m 2 /3 h/week x 6, during EBRT, with no exacerbation of typical RT-induced toxicities. The Radiation Therapy Oncology Group (RTOG) therefore mounted a Phase II study to determine the feasibility and efficacy of conventional EBRT and concurrent weekly TAX at its MTD. Patients and Methods: Sixty-two patients with histologic diagnosis of GBM were enrolled from 8/16/96 through 3/21/97 in a multi-institutional Phase II trial of EBRT and TAX 225 mg/m 2 /3 h (1-3 h before EBRT), administered the first treatment day of each RT week. Total EBRT dose was 60 Gy (200 cGy/fraction), 5 days per week. A smaller treatment field, to include gross disease plus a margin only, was used after 46 Gy. Results: Sixty-one patients (98%) were evaluable. Median age was 55 years (range, 28-78). Seventy-four percent were ≥50 years. Recursive partitioning analysis (RPA) Classes III, IV, V, VI included 10 (17%), 21 (34%), 25 (41%), and 5 (8%) patients, respectively. Gross total resection was performed in only 16%. There was no Grade 3 or 4 neutropenia or thrombocytopenia. Hypersensitivity reactions precluding further use of TAX occurred in 4 patients. There were 2 instances of late neurotoxicity (4% Grade 3 or 4). Ninety-one percent of patients received treatment per protocol. Seventy-seven percent completed prescribed treatment (6 weeks). Of 35 patients with measurable disease, CR/PR was observed in 23%, MR in 17%, and SD in 43%. Seventeen percent demonstrated progression at first follow-up. Median potential follow-up time is 20 months. Median survival is 9.7 months, with median survivals for RPA classes III, IV, V, and VI of 16.3, 10

  5. The use of the SRIM code for calculation of radiation damage induced by neutrons

    Science.gov (United States)

    Mohammadi, A.; Hamidi, S.; Asadabad, Mohsen Asadi

    2017-12-01

    Materials subjected to neutron irradiation will being evolve to structural changes by the displacement cascades initiated by nuclear reaction. This study discusses a methodology to compute primary knock-on atoms or PKAs information that lead to radiation damage. A program AMTRACK has been developed for assessing of the PKAs information. This software determines the specifications of recoil atoms (using PTRAC card of MCNPX code) and also the kinematics of interactions. The deterministic method was used for verification of the results of (MCNPX+AMTRACK). The SRIM (formely TRIM) code is capable to compute neutron radiation damage. The PKAs information was extracted by AMTRACK program, which can be used as an input of SRIM codes for systematic analysis of primary radiation damage. Then the Bushehr Nuclear Power Plant (BNPP) radiation damage on reactor pressure vessel is calculated.

  6. Intercomparison of radiotherapy treatment planning systems using calculated and measured dose distributions for external photon and electron beams

    International Nuclear Information System (INIS)

    Kosunen, A.; Jaervinen, H.; Vatnitskij, S.; Ermakov, I.; Chervjakov, A.; Kulmala, J.; Pitkaenen, M.; Vaeyrynen, T.; Vaeaenaenen, A.

    1991-02-01

    The requirement of 5 % overall accuracy for the target absorbed dose in radiotherapy implies that the accuracy of the relative dose calculation should be within only a few per cent. According to the recommendation by the International Commission on radiation units and measurements (ICRU), a computer-produced dose distribution can be considered to be accurate enough if it differs from the results of relative dose measurements by less than 2 %, or 2 mm in the position of isodose curves involving very steep dose gradients. In this study five treatment planning systems, currently used by the hospitals in Finland or in the USSR, were intercompared with respect to the above requirement. Five typical cases of irradiation were selected: regular fields, oblique incidence, irregular field, wedge field and inhomogeneity in a water equivalent phantom. Complete dose distributions were used for the intercomparison, and the beam data for each TPS was that pertaining to the beam where the comparative relative measurements were performed. The results indicate that the dose distributions produced by different TPS:s can differ from each other as well as from the measured dose distributions up to a level which is not acceptable in terms of the above requirement. Greatest differences seem to be related to the omission or undue consideration of the scatter components of the beam. A suitable quality assurance program for the systematic testing of the performance of the treatment planning systems could be based on a selection of tests as used in this study.(orig.)

  7. Unresectable Retiform Hemangioendothelioma Treated with External Beam Radiation Therapy and Chemotherapy: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Alina Z. Hirsh

    2010-01-01

    Full Text Available Retiform hemangioendothelioma (RH is an infrequently encountered vascular neoplasm of intermediate or borderline malignancy. Treatment of RH is controversial. We present a case of a 44-year-old Asian male presenting with an unresectable RH of the pelvis. The patient was treated with concurrent low-dose Cisplatin and External beam Radiation (4140cGy in 180cGy per fraction. This is the first report of a clinical complete response and a long-term local control of this rare tumor. This has significant clinical implication, since it gives the first evidence of treatment of this rare tumor using concurrent low-dose chemotherapy and radiation.

  8. Guidelines for calculating radiation doses to the public from a release of airborne radioactive material under hypothetical accident conditions in nuclear reactors

    International Nuclear Information System (INIS)

    1991-04-01

    This standard provides guidelines and a methodology for calculating effective doses and thyroid doses to people (either individually or collectively) in the path of airborne radioactive material released from a nuclear facility following a hypothetical accident. The radionuclides considered are those associated with substances having the greatest potential for becoming airborne in reactor accidents: tritium (HTO), noble gases and their daughters, radioiodines, and certain radioactive particulates (Cs, Ru, Sr, Te). The standard focuses on the calculation of radiation doses for external exposures from radioactive material in the cloud; internal exposures for inhalation of radioactive material in the cloud and skin penetration of tritium; and external exposures from radionuclides deposited on the ground. It uses as modified Gaussian plume model to evaluate the time-integrated concentration downwind. (52 refs., 12 tabs., 21 figs.)

  9. WE-D-210-04: Radiation-Induced Polymerization of Ultrasound Contrast Agents in View of Non-Invasive Dosimetry in External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Callens, M; Verboven, E; Van Den Abeele, K [Department of Physics, Wave Propagation and Signal Processing, KU Leuven KULAK, Kortrijk (Belgium); D’Agostino, E [DoseVue NV, Hasselt (Belgium); Pfeiffer, H [Department of Materials Engineering, KU Leuven, Leuven (Belgium); D’hooge, J [Department of Cardiovascular Sciences, Bio-Medical Science Group, KU Leuven, Leuven (Belgium)

    2015-06-15

    Purpose: Ultrasound contrast agents (UCA’s) based on gas-filled microbubbles encapsulated by an amphiphilic shell are well established as safe and effective echo-enhancers in diagnostic imaging. In view of an alternative application of UCA’s, we investigated the use of targeted microbubbles as radiation sensors for external beam radiation therapy. As radiation induces permanent changes in the microbubble’s physico-chemical properties, a robust measure of these changes can provide a direct or indirect estimate of the applied radiation dose. For instance, by analyzing the ultrasonic dispersion characteristics of microbubble distributions before and after radiation treatment, an estimate of the radiation dose at the location of the irradiated volume can be made. To increase the radiation sensitivity of microbubbles, polymerizable diacetylene molecules can be incorporated into the shell. This study focuses on characterizing the acoustic response and quantifying the chemical modifications as a function of radiation dose. Methods: Lipid/diacetylene microbubbles were irradiated with a 6 MV photon beam using dose levels in the range of 0–150 Gy. The acoustic response of the microbubbles was monitored by ultrasonic through-transmission measurements in the range of 500 kHz to 20 MHz, thereby providing the dispersion relations of the phase velocity, attenuation and nonlinear coefficient. In addition, the radiation-induced chemical modifications were quantified using UV-VIS spectroscopy. Results: UV-VIS spectroscopy measurements indicate that ionizing radiation induces the polymerization of diacetylenes incorporated in the microbubble shell. The polymer yield strongly depends on the shell composition and the radiation-dose. The acoustic response is inherently related to the visco-elastic properties of the shell and is strongly influenced by the shell composition and the physico-chemical changes in the environment. Conclusion: Diacetylene-containing microbubbles are

  10. Calculational results for radiation embrittlement of WWER pressure vessel at the Kozloduy NPP

    Energy Technology Data Exchange (ETDEWEB)

    Apostolov, T; Ilieva, K; Petrova, T [Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. za Yadrena Izsledvaniya i Yadrena Energetika

    1996-12-31

    Determination of radiation impact on metal state in the case of WWER-440/230 is made only by calculation methods since a special sample-witness (SW) incorporation had not been implemented. In WWER-1000 reactors such SW are foreseen but their spots are high above the active core. This is why in both reactors the appliance of a calculational procedure for radiation embrittlement determination is compulsory. The authors propose such a procedure accounting for the change in critical temperature of neutron brittleness by the neutron fluence. The neutron fluence and the shift of critical embrittlement temperature have been calculated for the maximum overloaded location and for the weld metal of the Kozloduy-5 and Kozloduy-6 reactors (WWER-1000). The shift of critical temperature in weld 4 of the Units 1-4 (WWER-440) is plotted versus work cycles and compared to experimental values. 4 figs., 5 tabs.

  11. Clinical significance of increased gelatinolytic activity in the rectal mucosa during external beam radiation therapy of prostate cancer

    International Nuclear Information System (INIS)

    Hovdenak, Nils; Wang Junru; Sung, C.-C.; Kelly, Thomas; Fajardo, Luis F.; Hauer-Jensen, Martin

    2002-01-01

    Purpose: Rectal toxicity (proctitis) is a dose-limiting factor in pelvic radiation therapy. Mucosal atrophy, i.e., net extracellular matrix degradation, is a prominent feature of radiation proctitis, but the underlying mechanisms are not known. We prospectively examined changes in matrix metalloproteinase (MMP)-2 and MMP-9 (gelatinase A and B) in the rectal mucosa during radiation therapy of prostate cancer, as well as the relationships of these changes with symptomatic, structural, and cellular evidence of radiation proctitis. Methods and Materials: Seventeen patients scheduled for external beam radiation therapy for prostate cancer were prospectively enrolled. Symptoms of gastrointestinal toxicity were recorded, and endoscopy with biopsy of the rectal mucosa was performed before radiation therapy, as well as 2 and 6 weeks into the treatment course. Radiation proctitis was assessed by endoscopic scoring, quantitative histology, and quantitative immunohistochemistry. MMP-2 and MMP-9 were localized immunohistochemically, and activities were determined by gelatin zymography. Results: Symptoms, endoscopic scores, histologic injury, and mucosal macrophages and neutrophils increased from baseline to 2 weeks. Symptoms increased further from 2 weeks to 6 weeks, whereas endoscopic and cellular evidence of proctitis did not. Compared to pretreatment values, there was increased total gelatinolytic activity of MMP-2 and MMP-9 at 2 weeks (p=0.02 and p=0.004, respectively) and 6 weeks (p=0.006 and p=0.001, respectively). Active MMP-2 was increased at both time points (p=0.0001 and p=0.002). Increased MMP-9 and MMP-2 at 6 weeks was associated with radiation-induced diarrhea (p=0.007 and p=0.02, respectively) and with mucosal neutrophil infiltration (rho=0.62). Conclusions: Pelvic radiation therapy causes increased MMP-2 and MMP-9 activity in the rectal mucosa. These changes correlate with radiation-induced diarrhea and granulocyte infiltration and may contribute to abnormal

  12. Migration of intraprostatic fiducial markers and its influence on the matching quality in external beam radiation therapy for prostate cancer

    International Nuclear Information System (INIS)

    Delouya, Guila; Carrier, Jean-Francois; Beliveau-Nadeau, Dominic; Donath, David; Taussky, Daniel

    2010-01-01

    Purpose: To assess the influence of fiducial marker (FM) migration on the matching quality in external beam radiation therapy (EBRT) for prostate cancer. Materials and methods: The position of FMs were identified using on-board kV imaging (OBI) and their 3-D position established using an in-house reconstruction algorithm for 31 patients with prostate adenocarcinoma. To carry out the match, the positions were overlaid on the digitally reconstructed radiographs (DRR) generated from the planning CT. The distance between each FM was calculated for seven treatments throughout the EBRT course. Four radiotherapy technologists were asked to independently perform and rate the match from OBI to DRR which was then correlated to the extent of FM migration. Results: All the matches were rated by at least three radiotherapy technologists as 'very easy' ('easy' subgroup) for 24 patients (77%), while the other seven patients had their match rated less than 'very easy' and considered the 'not easy' subgroup. The average daily FM migration was 0.93 ± 0.34 mm for the 'easy' subgroup vs. 1.82 ± 0.75 mm for the latter. An average migration >2 mm was seen in five/seven patients in the 'not easy' subgroup as compared to none in the 'easy' subgroup. There was a trend towards less FM migration and better matching if the planning CT was done later than the day of the FM implant (p = 0.093). Conclusions: FM migration >2 mm predicts for a more difficult matching process; PTV margins might have to be adjusted or the planning CT repeated.

  13. Calculation of radiation exposures from patients to whom radioactive materials have been administered

    Science.gov (United States)

    Cormack, John; Shearer, Jane

    1998-03-01

    Spreadsheet templates which calculate cumulative exposures to other persons from patients to whom radioactive materials have been administered have been developed by the authors. Calculations can be based on any specified single-, bi- or tri-exponential whole-body clearance rate and a diurnal (or any other periodic) contact pattern. The time (post-administration) during which close contact should be avoided in order to constrain the radiation exposure and exposure rates to selected limits is also calculated using an iterative technique (Newton's method), and the residual activity at the time when contact can resume is also calculated. These templates find particular application in the calculation of exposures to persons who are in contact with patients who have received for therapeutic purposes. The effect of changing dose limits, contact patterns and using individually derived clearance rates may be readily modelled.

  14. Measurement of secondary cosmic radiation and calculation of associated dose conversion coefficients for humans

    International Nuclear Information System (INIS)

    Simmer, Gregor

    2012-01-01

    Due to secondary cosmic radiation (SCR), pilots and flight attendants receive elevated effective doses at flight altitudes. For this reason, since 2003 aircrew members are considered as occupationally exposed, in Germany. This work deals with the calculation of dose conversion coefficients (DCC) for protons, neutrons, electrons, positrons, photons and myons, which are crucial for estimation of effective dose from SCR. For the first time, calculations were performed combining Geant4 - a Monte Carlo code developed at CERN - with the voxel phantoms for the reference female and male published in 2008 by ICRP and ICRU. Furthermore, measurements of neutron fluence spectra - which contribute the major part to the effective dose of SCR - were carried out at the Environmental Research Station Schneefernerhaus (UFS) located at 2650 m above sea level nearby the Zugspitze mountain, Germany. These measured neutron spectra, and additionally available calculated spectra, were then folded with the DCC calculated in this work, and effective dose rates for different heights were calculated.

  15. Calculation and mapping of direct and diffuse solar radiation in Costa Rica

    International Nuclear Information System (INIS)

    Wright, Jaime

    2008-01-01

    Knowledge of direct and diffuse solar radiation has been of vital importance in assessing the energy potential of Costa Rica. The work is focused on the calculation and plotting of contour maps of the direct and diffuse solar radiation, based in sixty-two radiometric stations scattered throughout the country. In tracing these contours have been used experimental and predicted values of direct and diffuse radiation. Additionally, direct and diffuse solar radiation is compared during the dry season and the rainy season in the six climatic regions of the country: Valle Central, North Pacific, Central Pacific, South Pacific, North Zone and Caribbean Region. Daily average levels of radiation observed directly have been from 6.1 and 10.1 MJ/m 2 , with higher values in the northern sections of the Pacific Slope, west of Valle Central and the tops of the highest mountains. The lowest values have coincided with the North Zone and Caribbean Region. The highest values of diffuse radiation have coincided with the North Zone and South Pacific. An increase in direct solar radiation by 40% is observed in the month of the dry season. (author) [es

  16. New ICRU quantities for the environmental and individual monitoring. Standardization of individual dosemeters by using external beams of photon radiation

    International Nuclear Information System (INIS)

    Brosed, A.; Delgado, A.; Granados, C. E.

    1987-01-01

    The quantities introduced by ICRU for the radiological monitoring are commented, specially those implied in individual protection against external photons. A procedure is proposed in order to standardize the individual dosemeters by using the kerma in air references of CIEMAT-JEN. The reference radiation beams are described in connection with ISO standards. Provisional values are selected for the appropriate conversion and correction factors. (Author) 23 refs