WorldWideScience

Sample records for external radiation levels

  1. 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

  2. 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 ...

  3. 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)

  4. 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

  5. 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)

  6. 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

  7. 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

  8. 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.

  9. Natural radiation external exposures levels in Chilean Sub-Antarctic and country stations

    International Nuclear Information System (INIS)

    Stuardo, E.

    1988-01-01

    Since 1983 gamma exposures levels, at 1,5 m above the soil are being investigated using TLD detectors. A network of 12 stations have been established from ARICA (18 deg 20' S latitude) in Northern Chile to YELCHO (64 deg 52' S latitude) in Antartic territory. One year monitoring period was used at Antartic stations and a four months period in the country. The main subject of this study is to assess the average background radiation levels along the territory which is relevant to get a reference level and specially an estimate of the average natural radiation contribution to the population dose in Southern Chile

  10. Study on Public Exposure and External Radiation Level at Gamma Green House and around MINT Dengkil Complex Boarder

    International Nuclear Information System (INIS)

    Faizal Azrin Abdul Razalim; Ismail Sulaiman; Khairuddin Mohamad Kontol; Ahmad Bazlie Abdul Kadir; Noor Fadilla Ismail; Hassan Sham; Ahmad Zainuri Mohd Dzomir

    2014-01-01

    This paper will discussing on the measurement of external radiation and the dose level which is acceptable to the public around the Gamma Green House and the border between Malaysian Nuclear Agency and housing project developed by Mah Sing Group. This research is made to verify the level of safety, especially for civilians residing in this area and to ensure compliance with the limit that has been set by the authorities, AELB (BSS/2010). Measurement method used in this research by using survey meter, TLD and OSL. (author)

  11. External exposure level from natural radiation and population dose in Gansu province

    International Nuclear Information System (INIS)

    Guo Shanxiang; Li Fuzeng; Jiao Yufang

    1985-01-01

    The resultts of measurement of absorbed dose rate in air from natural gamma radiation in Gansu measured with FD-71 scintillation radiometers are reported in this paper. Sketch maps of distribution of absorbed dose rates from natural radiation in this province are also presented. The mean values of absorbed rates in air from terrestrial gamma radiation for outdoors and indoors are 0.7 mGy/a (range 0.32 to 1.11 mGy/a) and 1.02 mGy/a (range 0.73 to 1.4 mGy/a), respectively. The annual effective dose equivalent from terrestrial gamma radiation to population in this province is estimated to be 1,14 mSv

  12. 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

  13. 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

  14. 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

  15. 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

  16. Personnel Dosimetry for Radiation Accidents. Proceedings of a Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation

    International Nuclear Information System (INIS)

    1965-01-01

    Accidents involving the exposure of persons to high levels of radiation have been few in number and meticulous precautions are taken in an effort to maintain this good record. When, however, such an accident does occur, a timely estimate of the dose received can be of considerable help to the physician in deciding whether a particular person requires medical treatment, and in selecting the most appropriate treatment. Individual dosimetry provides the physical basis for relating the observed effects to those in other accident cases, to other human data, and to data from animal experiments, thus providing an important aid to rational treatment and to the accumulation of a meaningful body of knowledge on the subject. It is most important therefore that, where there is a possibility of receiving high-level exposure, methods of personnel dosimetry should be available that would provide the dosimetric information most useful to the physician. Provision of good personnel dosimetry for accidental high-level exposure is in many cases an essential part of emergency planning because the information provided may influence emergency and rescue operations, and can lead to improved accident preparedness. Accordingly, the International Atomic Energy Agency and the World Health Organization jointly organized the Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation for the discussion of such methods and for a critical review of the procedures adopted in some of the radiation accidents that have already occurred. The meeting was attended by 179 participants from 34 countries and from five other international organizations. The papers presented and the ensuing discussions are published in these Proceedings. It is hoped that the Proceedings will be of help to those concerned with the organization and development of wide-range personnel monitoring systems, and with the interpretation of the results provided

  17. 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.

  18. 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

  19. External doses from radioactive fallout. Dosimetry and levels

    International Nuclear Information System (INIS)

    Woehni, T.

    1995-01-01

    The design, manufacture and calibration of a TL-based dosemeter for measurement of low level external photon radiation are presented. The dosemeter is based on CaF 2 with 2 mm brass filter for energy compensation. It is able to resolve a 8% dose increase relative to natural background radiation. With this dosemeter external dose measurements were made in 6 villages in a heavily contaminated region in Russia (Chernobyl fallout), in order to assess external doses to the population. The results were analyzed in the light of additional existing information on radioactive deposition, social habits, decontamination measures and other influencing technical and physical factors. The observed dose values were lower than theoretical estimates of external doses based on published values for external dose levels relative to the level of contamination. 84 refs., 7 figs., 5 tabs

  20. External doses from radioactive fallout. Dosimetry and levels

    Energy Technology Data Exchange (ETDEWEB)

    Woehni, T

    1996-12-31

    The design, manufacture and calibration of a TL-based dosemeter for measurement of low level external photon radiation are presented. The dosemeter is based on CaF{sub 2} with 2 mm brass filter for energy compensation. It is able to resolve a 8% dose increase relative to natural background radiation. With this dosemeter external dose measurements were made in 6 villages in a heavily contaminated region in Russia (Chernobyl fallout), in order to assess external doses to the population. The results were analyzed in the light of additional existing information on radioactive deposition, social habits, decontamination measures and other influencing technical and physical factors. The observed dose values were lower than theoretical estimates of external doses based on published values for external dose levels relative to the level of contamination. 84 refs., 7 figs., 5 tabs.

  1. External doses from radioactive fallout. Dosimetry and levels

    Energy Technology Data Exchange (ETDEWEB)

    Woehni, T.

    1995-12-31

    The design, manufacture and calibration of a TL-based dosemeter for measurement of low level external photon radiation are presented. The dosemeter is based on CaF{sub 2} with 2 mm brass filter for energy compensation. It is able to resolve a 8% dose increase relative to natural background radiation. With this dosemeter external dose measurements were made in 6 villages in a heavily contaminated region in Russia (Chernobyl fallout), in order to assess external doses to the population. The results were analyzed in the light of additional existing information on radioactive deposition, social habits, decontamination measures and other influencing technical and physical factors. The observed dose values were lower than theoretical estimates of external doses based on published values for external dose levels relative to the level of contamination. 84 refs., 7 figs., 5 tabs.

  2. 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

  3. 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...

  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. 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

  9. 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.

  10. 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.

  11. 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)

  12. 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

  13. Low-level radiation

    International Nuclear Information System (INIS)

    Myers, D.K.

    1982-05-01

    It is known that the normal incidence of cancer in human populations is increased by exposure to moderately high doses of ionizing radiation. At background radiation levels or at radiation levels which are 100 times greater, the potential health risks are considered to be directly proportional to the total accumulated dose of radiation. Some of the uncertainties associated with this assumption and with the accepted risk estimates have been critically reviewed in this document. The general scientific consensus at present suggests that the accepted risk estimates may exaggerate the actual risk of low levels of sparsely ionizing radiations (beta-, gamma- or X-rays) somewhat but are unlikely to overestimate the actual risks of densely ionizing radiations (fast neutrons, alpha-particles). At the maximum permissible levels of exposure for radiation workers in nuclear power stations, the potential health hazards in terms of life expectancy would be comparable to those encountered in transportation and public utilities or in the construction industry. At the average radiation exposures received by these workers in practice, the potential health hazards are similar to those associated with safe categories of industries. Uranium mining remains a relativly hazardous occupation. In terms of absolute numbers, the genetic hazards, which are less well established, are thought to be smaller than the carcinogenic hazards of radiation when only the first generation is considered but to be of the same order of magnitude as the carcinogenic hazards when the total number of induced genetic disorders is summed over all generations

  14. 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

  15. 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.

  16. Radiation Level Changes at RAM Package Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Opperman, Erich [Washington Savannah River Company; Hawk, Mark B [ORNL; Kapoor, Ashok [U.S. Department of Energy, Office of Packaging and Transportation; Natali, Ronald [R. B. Natali Consulting, Inc.

    2010-01-01

    This paper will explore design considerations required to meet the regulations that limit radiation level variations at external surfaces of radioactive material (RAM) packages. The radiation level requirements at package surfaces (e.g. TS-R-1 paragraphs 531 and 646) invoke not only maximum radiation levels, but also strict limits on the allowable increase in the radiation level during transport. This paper will explore the regulatory requirements by quantifying the amount of near surface movement and/or payload shifting that results in a 20% increase in the radiation level at the package surface. Typical IP-2, IP-3, Type A and Type B packaging and source geometries will be illustrated. Variations in surface radiation levels are typically the result of changes in the geometry of the surface due to an impact, puncture or crush event, or shifting and settling of radioactive contents.

  17. 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

  18. 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

  19. 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

  20. 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.

  1. 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)

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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.

  9. Radiation levels in eastern Europe

    International Nuclear Information System (INIS)

    Webb, G.A.M.; Simmonds, J.R.; Wilkins, B.T.

    1986-01-01

    Immediately after news of the accident at Chernobyl became available on 28 April, the National Radiological Protection Board (NRPB) was asked by the UK Foreign and Commonwealth Office (FCO) for an appraisal of the radiation situation on the basis of which advice would be given to embassy staff, residents in affected countries and prospective travellers. The first Swedish measurements, external gamma dose rates and, later, concentrations of atmospheric and ground radioactivity, were used to estimate the quantity of radioactivity released by means of NRPB's accident consequence code (1), MARC. Our first predictions of 29 April indicated a substantial release of the order of 10 17 - 10 18 Bq, which was expected to lead to tens of early radiation-induced deaths in the area around the site. On the basis of NRPB's recommended Emergency Reference Levels (ERL's), it was thought that there would be a need for evacuation out to 20 to 30 km and for temporary food restrictions out to a few hundred kilometres from the site. FCO accordingly decided to evacuate students from Kiev and Minsk and to advise people not to travel to the western Soviet Union or to north-east Poland unless absolutely necessary

  10. 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.)

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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.

  16. 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.)

  17. 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

  18. 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

  19. 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)

  20. 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)

  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. 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)

  3. Ambient radioactivity levels and radiation doses. Annual report 2011

    International Nuclear Information System (INIS)

    Bernhard-Stroel, Claudia; Hachenburger, Claudia; Trugenberger-Schnabel, Angela; Peter, Josef

    2013-07-01

    The annual report 2011 on ambient radioactivity levels and radiation doses covers the following issues: Part A: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. Part B; Current data and their evaluation: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. The Appendix includes Explanations of terms, radiation doses and related units, external and internal radiation exposure, stochastic and deterministic radiation effects, genetic radiation effects, induction of malignant neoplasm, risk assessment, physical units and glossary, laws, ordinances, guidelines, recommendations and other regulations concerning radiation protection, list of selected radionuclides.

  4. 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

  5. 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)

  6. 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

  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. 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.)

  9. 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)

  10. 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)

  11. 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.)

  12. 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.

  13. 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.

  14. 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

  15. Low level radiation: biological effects

    International Nuclear Information System (INIS)

    Loken, M.K.

    1983-01-01

    It is imperative that physicians and scientists using radiations in health care delivery continue to assess the benefits derived, vs. potential risk, to patients and radiation workers being exposed to radiation in its various forms as part of our health delivery system. Insofar as possible we should assure our patients and ourselves that the benefits outweigh the potential hazards involved. Inferences as to the possible biological effects of low level radiation are generally based on extrapolations from those effects observed and measured following acute exposures to considerably higher doses of radiation. Thus, in order to shed light on the question of the possible biological effects of low level radiation, a wide variety of studies have been carried out using cells in culture and various species of plant and animal life. This manuscript makes reference to some of those studies with indications as to how and why the studies were done and the conclusions that might be drawn there from. In addition reference is made to the handling of this information by scientists, by environmentalists, and by the news media. Unfortunately, in many instances the public has been misled by what has been said and/or written. It is hoped that this presentation will provide an understandable and reasonable perspective on the various appropriate uses of radiation in our lives and how such uses do provide significant improvement in our health and in our quality of life

  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. 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.

  18. 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

  19. 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)

  20. 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.

  1. 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

  2. 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.)

  3. 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)

  4. 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

  5. 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)

  6. 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

  7. Effects of interaural level differences on the externalization of sound

    DEFF Research Database (Denmark)

    Catic, Jasmina; Santurette, Sébastien; Dau, Torsten

    2012-01-01

    Distant sound sources in our environment are perceived as externalized and are thus properly localized in both direction and distance. This is due to the acoustic filtering by the head, torso, and external ears, which provides frequency-dependent shaping of binaural cues such as interaural level...... differences (ILDs) and interaural time differences (ITDs). In rooms, the sound reaching the two ears is further modified by reverberant energy, which leads to increased fluctuations in short-term ILDs and ITDs. In the present study, the effect of ILD fluctuations on the externalization of sound......, for sounds that contain frequencies above about 1 kHz the ILD fluctuations were found to be an essential cue for externalization....

  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. 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.

  10. 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.)

  11. Chromosome Aberration on High Level Background Natural Radiation Areas

    International Nuclear Information System (INIS)

    Yanti-Lusiyanti; Zubaidah-Alatas

    2001-01-01

    When the body is irradiated, all cells can suffer cytogenetic damage that can be seen as structural damage of chromosome in the lymphocytes. People no matter where they live in world are exposed to background radiation from natural sources both internal and external such as cosmic radiation, terrestrial radiation, cosmogenic radiation radon and thoron. Level of area natural ionizing radiation is varies depending on the altitude, the soil or rock conditions, particular food chains and the building materials and construction features. Level of normal areas of background exposure is annual effective dose 2.4 mSv and the high level areas of background exposure 20 mSv. This paper discuses the frequency of aberration chromosome especially dysenteries in several countries having high level radiation background. It seems that frequency of chromosome aberrations increase, generally with the increase of age of the people and the accumulated dose received. (author)

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. Radiation Levels around the LHC

    CERN Document Server

    Mala, P; Calviani, M; Nordt, A

    2013-01-01

    This work discuss on the radiation levels measured around the LHC machine during the 2012 operational year. The doses and particle fluences are measured primarily by RadMon detectors – about 300 RadMons are installed around the accelerator – and by thermoluminescent detectors. In addition, BLMs, IG5/PMI ionisation chambers as well as FGCs can be used for corresponding cumulated dose evaluations. The probability of SEE depends directly on the high-energy hadron (HEH) fluence, so this is the main parameter that is calculated based on RadMons counts.

  17. 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

  18. 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.

  19. 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

  20. 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)

  1. 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

  2. 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)

  3. 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)

  4. 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

  5. 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.

  6. Split energy level radiation detection

    International Nuclear Information System (INIS)

    Barnes, G.T.

    1986-01-01

    This patent describes an energy discriminating radiation detector comprising: (a) a first element comprising a first material of a kind which is preferentially responsive to penetrative radiation of a first energy range; (b) a second element comprising a second material different in kind from the first material and of a kind which is preferentially responsive to penetrative radiation of second energy range extending higher than the first energy range. The element is positioned to receive radiation which has penetrated through a portion of the first element; and (c) a filter of penetrative radiation interposed between the first and second elements

  7. Two interacting spins in external fields. Four-level systems

    Energy Technology Data Exchange (ETDEWEB)

    Bagrov, V.G.; Baldiotti, M.C.; Gitman, D.M. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318-CEP, 05315-970 Sao Paulo, S.P. (Brazil); Levin, A.D. [Dexter Research Center (United States)

    2007-04-15

    In the present article, we consider the so-called two-spin equation that describes four-level quantum systems. Recently, these systems attract attention due to their relation to the problem of quantum computation. We study general properties of the two-spin equation and show that the problem for certain external backgrounds can be identified with the problem of one spin in an appropriate background. This allows one to generate a number of exact solutions for two-spin equations on the basis of already known exact solutions of the one-spin equation. Besides, we present some exact solutions for the two-spin equation with an external background different for each spin but having the same direction. We study the eigenvalue problem for a time-independent spin interaction and a time-independent external background. A possible analogue of the Rabi problem for the two-spin equation is defined. We present its exact solution and demonstrate the existence of magnetic resonances in two specific frequencies, one of them coinciding with the Rabi frequency, and the other depending on the rotating field magnitude. The resonance that corresponds to the second frequency is suppressed with respect to the first one. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  8. 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

  9. 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

  10. Silicon photonic dynamic optical channel leveler with external feedback loop.

    Science.gov (United States)

    Doylend, J K; Jessop, P E; Knights, A P

    2010-06-21

    We demonstrate a dynamic optical channel leveler composed of a variable optical attenuator (VOA) integrated monolithically with a defect-mediated photodiode in a silicon photonic waveguide device. An external feedback loop mimics an analog circuit such that the photodiode directly controls the VOA to provide blind channel leveling within +/-1 dB across a 7-10 dB dynamic range for wavelengths from 1530 nm to 1570 nm. The device consumes approximately 50 mW electrical power and occupies a 6 mm x 0.1 mm footprint per channel. Dynamic leveling is accomplished without tapping optical power from the output path to the photodiode and thus the loss penalty is minimized.

  11. 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)

  12. 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)

  13. Multiple external hazards compound level 3 PSA methods research of nuclear power plant

    Science.gov (United States)

    Wang, Handing; Liang, Xiaoyu; Zhang, Xiaoming; Yang, Jianfeng; Liu, Weidong; Lei, Dina

    2017-01-01

    2011 Fukushima nuclear power plant severe accident was caused by both earthquake and tsunami, which results in large amount of radioactive nuclides release. That accident has caused the radioactive contamination on the surrounding environment. Although this accident probability is extremely small, once such an accident happens that is likely to release a lot of radioactive materials into the environment, and cause radiation contamination. Therefore, studying accidents consequences is important and essential to improve nuclear power plant design and management. Level 3 PSA methods of nuclear power plant can be used to analyze radiological consequences, and quantify risk to the public health effects around nuclear power plants. Based on multiple external hazards compound level 3 PSA methods studies of nuclear power plant, and the description of the multiple external hazards compound level 3 PSA technology roadmap and important technical elements, as well as taking a coastal nuclear power plant as the reference site, we analyzed the impact of off-site consequences of nuclear power plant severe accidents caused by multiple external hazards. At last we discussed the impact of off-site consequences probabilistic risk studies and its applications under multiple external hazards compound conditions, and explained feasibility and reasonableness of emergency plans implementation.

  14. 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)

  15. Course of radiation protection: technical level

    International Nuclear Information System (INIS)

    2002-01-01

    The course handbook on radiation protection and nuclear safety, technical level prepared by scientists of the Nuclear Regulatory Authority (ARN) of the Argentina Republic, describes the subjects in 19 chapters and 2 annexes. These topics detailed in the text have the following aspects: radioactivity elements, interaction of the radiation and the matter, radio dosimetry, internal contamination dosimetry, principles of radiation detection, biological radiation effects, fundamentals of radiation protection, dose limits, optimization, occupational exposure, radiation shielding, radioactive waste management, criticality accidents, safe transport of radioactive materials, regulatory aspects

  16. 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

  17. 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.

  18. 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.

  19. 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

  20. Background radiation levels and standards for protection from ionizing radiations

    International Nuclear Information System (INIS)

    Farai, I.

    1999-01-01

    Apart from the amount of radiation which a worker may receive while he performs his work, he is also exposed to radiation because of the nature of his environment. In other words, all individuals are subject to some irradiation even though they may not work with radioactive substances. This source of radiation exposure is often referred to as background radiation. In most environments, it is low-level and can be grouped into two natural and man-made. Background radiation provides the basis on which allowable exposure limits for workers are drawn

  1. 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

  2. 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

  3. 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)

  4. Environmental gamma radiation levels around various DAE research centres

    International Nuclear Information System (INIS)

    Takale, R.A.; Swarnakar, M.; Shetty, P.G.; Sahu, S.K.; Pandit, G.G.

    2014-01-01

    This paper presents the gamma radiation levels of four research centres viz. Bhabha Atomic Research Centre (BARC), Trombay; Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam; Variable Energy Cyclotron Centre (VECC), Kolkata; Raja Ramanna Centre for Advanced Technology (RRCAT), Indore; and an industry Board of Radiation and Isotope Technology (BRIT), Vashi. BARC is India's premier nuclear research facility and is a multi-disciplinary research centre with extensive infrastructure for advanced research and development (R and D). IGCAR, Kalpakkam is engaged in scientific research and advanced engineering programme towards the development of Fast Breeder Reactor technology. VECC Kolkata is dedicated to carry out frontier R and D in the fields of Accelerator Science and Technology, Nuclear Science (Theoretical and Experimental), and Material Science etc. RRCAT, Indore has rapidly grown into a premier institute for R and D in lasers, accelerators and their applications. BRIT, Vashi unit is involved in production, development, and supply of radioisotope based products and provision of isotope applications, radiation processing, radio analytical services etc. With an objective to keep a watch on the prevailing environmental background gamma radiation level around all the DAE installations, routine monitoring programme are being carried out using the Thermo Luminescent Dosimeters (TLDs). TLDs provide the simple, inexpensive and precise measurement of small, integrated, external gamma radiation dose rate. The general practice of this programme is to observe the outdoor gamma radiation levels. This paper summarizes the methodology and gamma radiation levels of four research centres viz. BARC, IGCAR, VECC, RRCAT and an industry BRIT, Vashi

  5. Radiation exposure of airplane crews. Exposure levels

    International Nuclear Information System (INIS)

    Bergau, L.

    1995-01-01

    Even at normal height levels of modern jet airplanes, the flying crew is exposed to a radiation level which is higher by several factors than the terrestrial radiation. There are several ways in which this can be hazardous; the most important of these is the induction of malignant growths, i.e. tumours. (orig./MG) [de

  6. 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.

  7. 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

  8. 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)

  9. 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)

  10. 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.

  11. 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).

  12. 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

  13. 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)

  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. 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)

  17. 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.

  18. 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...

  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. 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)

  2. 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)

  3. Can low-level radiation cause cancer?

    International Nuclear Information System (INIS)

    Trosko, J.E.

    1995-01-01

    Health in a multicellular organism is maintained by homeostatic processes. Disruption of these homeostatic controls at the molecular, biochemical, cellular, and organ systems levels can be brought about by irreversible changes in the genetic material (mutagenesis), cell death (cytotoxicity), or reversible changes in the expression of genes at the transcriptional, translational, or posttranslational levels (epigenesis). While radiation is known to induce DNA damage/mutations, cell, death and epigenetic changes, in addition to cancers that are found in radiation-exposed animals, experimentally, and in humans, epidemiologically, the question is, At low-level exposure, what is the risk that cancers are open-quotes causedclose quotes by the radiation?

  4. 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.

  5. 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

  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. 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. Low-level radiation risks in people

    International Nuclear Information System (INIS)

    Goloman, M.; Filjushkin, V. lgor

    1993-01-01

    Using the limited human data plus the relationships derived from the laboratory, a leukemia risk model has been developed as well as a suggested model for other cancers in people exposed to low levels of radiation. Theoretical experimental and epidemiological evidence will be presented in an integrated stochastic model for projection of radiation-induced cancer risks

  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. 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

  13. About the principles of radiation level normalization

    International Nuclear Information System (INIS)

    Nosovskij, A.V.

    2000-01-01

    The paper highlights the impact being made by the radiation level normalization principles upon the social and economic indicators. The newly introduced radiation safety standards - 97 are taken as an example. It is emphasized that it is necessary to use a sound approach while defining radiation protection standards, taking into consideration economic and social factors existing in Ukraine at the moment. Based on the concept of the natural radiation background and available results of the epidemiological surveys, the dose limits are proposed for the radiation protection standards. The paper gives a description of the dose limitation system recommended by the International Committee for Radiation Protection. The paper highlights a negative impact of the line non threshold concept, lack of special knowledge in the medical service and mass media to make decisions to protect people who suffered from the Chernobyl accident

  14. High level natural radiation areas with special regard to Ramsar

    International Nuclear Information System (INIS)

    Sohrabi, M.

    1993-01-01

    The studies of high level natural radiation areas (HLNRAs) around the world are of great importance for determination of risks due to long-term low-level whole body exposures of public. Many areas of the world possess HLNRAs the number of which depends on the criteria defined. Detailed radiological studies have been carried out in some HLNRAs the results of which have been reported at least in three international conferences. Among the HLNRAs, Ramsar has so far the highest level of natural radiation in some areas where radiological studies have been of concern. A program was established for Ramsar and its HLNRAs to study indoor and outdoor gamma exposures and external and internal doses of the inhabitants, 226 Ra content of public water supplies and hot springs, of food stuffs, etc., 222 Rn levels measured in 473 rooms of near 350 houses, 16 schools and 89 rooms and many locations of old and new Ramsar Hotels in different seasons, cytogenetic effects on inhabitants of Talesh Mahalleh, the highest radiation area, compared to that of a control area and radiological parameters of a house with a high potential for internal and external exposures of the inhabitants. It was concluded that the epidemiological studies in a number of countries did not show any evidence of increased health detriment in HLNRAs compared to control groups. In this paper, the conclusions drawn from studies in some HLNRAs around the world in particular Ramsar are discussed. (author). 20 refs, 2 figs, 1 tab

  15. Level gauge using neutron radiation

    International Nuclear Information System (INIS)

    Mathew, P.J.

    1985-01-01

    Apparatus for determining the level of a solid or liquid material in a container comprises: a vertical guide within or alongside the container; a sensor positioned within the guide; means for moving the sensor along the guide; and means for monitoring the position of the sensor. The sensor comprises a source of fast neutrons, a detector for thermal neutrons, and a body of a neutron moderating material in close proximity to the detector. Thermal neutrons produced by fast neutron irradiation of the solid or liquid material, or thermal neutrons produced by irradiation of the neutron-moderating material by fast or epithermal neutrons reflected by the solid or liquid material, are detected when the sensor is positioned at or below the level of the material in the container

  16. Health effects of low level radiation exposure among radiation workers

    International Nuclear Information System (INIS)

    Murata, Motoi

    2003-01-01

    In Japan, a cohort study of radiation workers has been conducted since 1990. The cohort population consisted of about 176,000 workers (mostly males) who had been registered in the centralized radiation dose registry system and engaged in various radiation works at nuclear facilities. Statistical analyses were performed mainly on the 2,934 deaths, of which 1,191 were cancer cases, detected among 119,000 male subjects during the prospective follow-up. The standardized mortality ratio showed that for any cancers mortality was not different between this population and Japanese general population. By the trend test, though significantly increasing trend in accord with increasing doses was not observed for both cancer in all sites and leukemia, it was highly significant for esophagus cancer and external causes of deaths. Results of the questionnaire survey study of lifestyle of radiation workers suggested that increasing trend of these diseases was at least partly due to the influence of some confounding factors. As a result of reviewing published studies, including the present work, trend of mortality from cancer in all sites with increasing doses seems still unclear, whereas for leukemia it appears to stay flat under 100 mSv but rapidly rise up in the doses higher than this as if fitting to either a linear-quadratic or threshold models. (author)

  17. 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)

  18. 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)

  19. 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)

  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.

    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

  1. SGR-76 gamma radiation level indicator

    International Nuclear Information System (INIS)

    Chubinskij-Nadezhdin, I.V.

    1978-01-01

    The design of a gamma-radiation level indicator is described; the instrument is part of a mobile radiometric laboratory (MRL). The design of the instrument permits gamma-radiation dose rates recording at 0.2-200 R/hr, and signals on gamma-background levels. The instrument has two separate threshold levels of signalling actuation. The light signalling at the first level is precautionary, and the sound signalling at the second level indicates the necessity of taking a decision as to whether or not the MRL can remain in the gamma-radiation field. Halogenic counters operating in a current mode are used as detectors. The basic error in recording the dose rate amounts to +-25%. Overall dimensions of the instrument 150x280x100 mm; weight less than 2.5 kg

  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. 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

  4. 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

  5. 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

  6. 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

  7. 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)

  8. 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)

  9. 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)

  10. Time course of cerebellar catalase levels after neonatal ionizing radiations

    International Nuclear Information System (INIS)

    Di Meglio, A.; Caceres, L.; Zieher, L.M.; Guelman, L.R.

    2005-01-01

    Full text: Reactive oxygen species are physiologically generated as a consequence of aerobic respiration, but this generation is increased in response to external stimuli, including ionizing radiation. The central nervous system (CNS) is vulnerable to oxidative stress due to its high oxygen consumption rate, its high level of polyunsaturated fatty acids and low levels of antioxidant defences. An important compound of this defence system is the antioxidant enzyme catalase, an heme protein that removes hydrogen peroxide from the cell by catalyzing its conversion to water. The aim of the present work was to study if catalase is susceptible to oxidative stress generated by ionizing radiation on the cerebellum. Neonatal rats were irradiated with 5 Gy of X rays and the levels of catalase were measured at 15, 30 and 60 days of age. Results show that there is a decrease in the activity of catalase in irradiated cerebellum at 15 (% respect the control, 65.6 ± 14.8), 30 (51.35± 5.8%), and 60 days (9.3 ± 0.34%). Catalase activity at 15 and 30 days has shown to be positively correlated with the radiation-induced decrease in tissue's weight, while at 60 days there is an extra decrease. It would be suggested that, at long term, radiation exposure might induce, in addition to cerebellar atrophy, the oxidation of the radiosensitive heme group of the enzyme, leading to its inactivation. In conclusion, the antioxidant enzyme catalase has shown to be especially sensitive to ionizing radiation. (author)

  11. 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.)

  12. 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.).

  13. 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.)

  14. 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

  15. 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

  16. Radiobiologic effects at low radiation levels

    International Nuclear Information System (INIS)

    Casarett, G.W.

    1975-01-01

    Data are reviewed on the effects of low radiation doses on mammals. Data from the 1972 report on the Biological Effects of Ionizing Radiation issued by the Advisory Committee of the National Academy of Sciences and National Research Council are discussed. It was concluded that there are certain radiosensitive systems in which low doses of radiation may cause degenerative effects, including gametogenic epithelium, lens of the eye, and developing embryos. Despite extensive investigation of genetic effects, including chromosomal effects, neither the amount of change that will be caused by very low levels of irradiation nor the degree of associated detriment is known

  17. 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

  18. 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

  19. Human exposure to low level ionising radiation

    International Nuclear Information System (INIS)

    Paix, David

    1988-01-01

    This paper describes the low-level radiation sources and their effects on human populations, from a global perspective. 'Low-level' means exposures in the range of the natural background to which everybody is exposed. The quoted values are whole-world averages, but individual variations are mentioned in a few cases. (author). 22 refs

  20. 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

  1. 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.)

  2. 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)

  3. 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

  4. Radiation Dose Contribution To The Worker Health Level At Serpong Area

    International Nuclear Information System (INIS)

    Yuwono, Indro

    2000-01-01

    Analysis of internal and external radiation doses received for radiation and non-radiation workers of P2TBDU have been done. In the period of 1997/1998 and 1998/1999 there were no significant increasing level of radiation doses received that was 0.55 mSv and highest received radiation dose was 2.66% from dose limit value. Increasing of healthy difference on the same period was 5.76%. Increasing of healthy difference no cause by increasing of radiation dose received but maybe the food consumption design

  5. 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)

  6. 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.

  7. Health effects of low level radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hattori, Sadao [Central Research Inst. of Electric Power Industry, Tokyo (Japan)

    1998-12-31

    In 1982, Prof. Thomas Don Luckey of Missouri Univ. asserted `Radiation Hormesis` on the Journal of Health Physics and he published two books. CRIEPI initiated the research program on Radiation Hormesis following his assertion to confirm `is it true or not?` After nearly ten year research activities on data surveys and animal tests with many Universities, we are realizing scientific truth of bio-positive effects by low level radiation exposures. The interesting bio-positive effects we found could be categorized in following five groups. 1) Rejuvenation of cells such as increase of SOD and cell membrane permeability, 2) Moderation of psychological stress through response of key enzymes, 3) Suppression and therapy of adult-diseases such as diabetes and hypertension, 4) Suppression of cancer through enhancement of immune systems such as lymphocytes, 5) Suppression of cancer and ratio-adaptive response by activation of DNA repair and apoptosis. In the responses of many specialists to our initiation of radiation hormesis research program following T.D. Luckey`s claim about low level radiation, I have to pick up for the first, the great success of Prof. Sakamoto. Prof. Sakamoto had been already applying whole body low dose irradiation for ten years before our radiation hormesis research started on the therapy to suppress the cancer reappearing after treatment. He reported about his successful trial to real patients and showed an enhancement of immune system. (author)

  8. Health effects of low level radiation

    International Nuclear Information System (INIS)

    Hattori, Sadao

    1998-01-01

    In 1982, Prof. Thomas Don Luckey of Missouri Univ. asserted 'Radiation Hormesis' on the Journal of Health Physics and he published two books. CRIEPI initiated the research program on Radiation Hormesis following his assertion to confirm 'is it true or not?' After nearly ten year research activities on data surveys and animal tests with many Universities, we are realizing scientific truth of bio-positive effects by low level radiation exposures. The interesting bio-positive effects we found could be categorized in following five groups. 1) Rejuvenation of cells such as increase of SOD and cell membrane permeability, 2) Moderation of psychological stress through response of key enzymes, 3) Suppression and therapy of adult-diseases such as diabetes and hypertension, 4) Suppression of cancer through enhancement of immune systems such as lymphocytes, 5) Suppression of cancer and ratio-adaptive response by activation of DNA repair and apoptosis. In the responses of many specialists to our initiation of radiation hormesis research program following T.D. Luckey's claim about low level radiation, I have to pick up for the first, the great success of Prof. Sakamoto. Prof. Sakamoto had been already applying whole body low dose irradiation for ten years before our radiation hormesis research started on the therapy to suppress the cancer reappearing after treatment. He reported about his successful trial to real patients and showed an enhancement of immune system. (author)

  9. Alteration of the ground state by external magnetic fields. [External field, coupling constant ratio, static tree level approximation

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, B J; Shepard, H K [New Hampshire Univ., Durham (USA). Dept. of Physics

    1976-03-22

    By fully exploiting the mathematical and physical analogy to the Ginzburg-Landau theory of superconductivity, a complete discussion of the ground state behavior of the four-dimensional Abelian Higgs model in the static tree level approximation is presented. It is shown that a sufficiently strong external magnetic field can alter the ground state of the theory by restoring a spontaneously broken symmetry, or by creating a qualitatively different 'vortex' state. The energetically favored ground state is explicitly determined as a function of the external field and the ratio between coupling constants of the theory.

  10. 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

  11. 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

  12. 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)

  13. Background compensation for a radiation level monitor

    Science.gov (United States)

    Keefe, D.J.

    1975-12-01

    Background compensation in a device such as a hand and foot monitor is provided by digital means using a scaler. With no radiation level test initiated, a scaler is down-counted from zero according to the background measured. With a radiation level test initiated, the scaler is up-counted from the previous down-count position according to the radiation emitted from the monitored object and an alarm is generated if, with the scaler having crossed zero in the positive going direction, a particular number is exceeded in a specific time period after initiation of the test. If the test is initiated while the scale is down-counting, the background count from the previous down- count stored in a memory is used as the initial starting point for the up-count.

  14. Low-level radiation waste management system

    International Nuclear Information System (INIS)

    Kubofcik, K.W.

    1990-01-01

    This patent describes a low-level radiation waste container set for use in conjunction with an open-topped receptacle. It comprises: a receptacle liner having a closed end and an open end, the receptacle liner sized for deployment as an inserted liner in an open-topped receptacle for collecting low-level radiation waste material within the receptacle liner within the open-topped receptacle; a cover sized and shaped to fit over the open top of the open-topped receptacle and the receptacle liner therein with the cover is in a closed position. The cover having a depending skirt which, when the cover is in the closed position, extends downwardly to overlap the open-topped receptacle adjacent the open top thereof and a portion of the receptacle liner received therein; and the receptacle liner and cover being fabricated of flexible radiation shielding material

  15. 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.)

  16. Acceptance criteria for deposition of low-level and intermediate-level radiation levels radioactive wastes

    International Nuclear Information System (INIS)

    2002-09-01

    This norm establishes the criteria for acceptance low and intermediate radiation level for safe deposition in repositories, for assuring the protection of workers, population and environment against the hazardous effects of the ionizing radiations. The criteria of this norm applies to the low and intermediate radiation levels

  17. 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

  18. External evaluation in municipal level: The impacts of an experience

    Directory of Open Access Journals (Sweden)

    Luana Ferrarotto

    2015-11-01

    Full Text Available The external evaluation is a consolidated reality in our country. Besides the state and federal ones, there are some municipalities that develop their own evaluation programs. To contribute with the debate about the external evaluations, this article presents data from a research which aim was to identify the actions from the Educational Secretariat from a city in the State of São Paulo, Brazil, opposite to the results of PROMASE (Municipal Assessment of the Educational System and its impact in school’s units. It is still being analyzed the path taken by the program with the aim of explaining its conception of the teaching quality. This way, the qualitative research was chosen based on the interviews with the Educational Secretary, teachers and school’s managers. Accordingly with the Secretary, after PROMASE, actions since improvements in the buildings to curricular restructuring and continuing educational were made. Even without the rankings and performance payments, it is noticeable in schools the built of what is called “hidden” and “adjustment” rankings of the pedagogical and evaluative practices to the matrix and to the evaluative instrument of the program to improve the teaching quality and improve the index. For an evaluative system to bring contributions to the network, it is noticeable that the quality must be anchored to the social quality, which more than the index, establishes its own scale as a protagonist in the process of looking to itself, adverse to the blaming of the teachers for the standards tests results and that, consequently, favors the social, political, cultural and human formation of the students.

  19. 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

  20. 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

  1. 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

  2. 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

  3. Radiation levels in nuclear diagnostic examinations

    International Nuclear Information System (INIS)

    Vermeulen, A.M.T.I.

    1987-01-01

    To estimate the risks for a pregnant radiological worker, radiation level measurements are executed for common nuclear diagnostic techniques. These measurements are combined with the time which the radiologic worker is present during the performance of the diagnostic techniques. It is concluded that a radiologic worker is receiving less than 5 mSv during pregnancy. This is the case with in vivo determination in a department of nuclear medicine with common diagnostic techniques. Reduction of radiation doses during pregnancy is possible by reduction of heart function examinations, skeletal examinations and brain scans. 1 figure; 13 tabs

  4. 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.

  5. 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

  6. Ionizing radiation: levels and effects. Volume I. Levels

    International Nuclear Information System (INIS)

    1972-01-01

    This is the sixth substantive report of the United Nations Scientific Committee on the Effects of Atomic Radiation to the General Assembly. It reviews the levels of radiation received from all sources to which man is exposed and, among the effects of ionizing radiation, it considers the genetic effects, the effects on the immune response and the induction of malignancies in animals and man. These are not the only effects of ionizing radiation. The acute consequences of massive amounts of radiation that may be received accidentally or during nuclear warfare are not reviewed here (the short discussion of this subject in the 1962 report is still largely valid, at least as an introduction), nor are the effects on the nervous system and the induction of chromosome anomalies in somatic cells, which were both considered by the Committee in its 1969 report. Unlike previous reports of the Committee, the present report is submitted to the General Assembly without the technical annexes in which the evidence considered by the Committee is discussed in detail and in which the bases for the Committee's conclusions, which are stated in the report, are fully documented. However, the annexes are being made available at the same time as the report in a separate publication, issued in two volumes and the Committee wishes to draw the attention of the General Assembly to the fact that the separation of the report from the annexes is for convenience only and that major importance attaches to the scientific evidence given in the annexes.

  7. Low-level radiation: The cancer controversy

    International Nuclear Information System (INIS)

    Stewart, A.M.

    1990-01-01

    According to early studies it would be safe to assume there are no late effects of radiation apart from cancer, no lasting selective effects of the early deaths of A-bomb victims, and no cancer risk at low dose levels (below 20 rad). The nuclear establishment had good reason to believe that a potentially dangerous situation had been completely defused, and optimists were still free to regard daily exposure to background radiation as a benign influence. For several years the only indication to the contrary was the Oxford survey's finding on prenatal X-rays. But today we face the possibility that there are other late effects of radiation besides cancer; and the possibility that the selection effects of the two nuclear explosions are still reflected in death rates among survivors and are the reason why no cancer effects have been found at low dose levels. If these possibilities are confirmed, we may one day realize how fortunate it was that the Oxford survey findings put a brake on the enthusiasms of nuclear power advocates. Otherwise, we might never have pressed for direct studies of the effects of low doses of radiation. 7 refs

  8. 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)

  9. Current External Beam Radiation Therapy Quality Assurance Guidance: Does It Meet the Challenges of Emerging Image-Guided Technologies?

    International Nuclear Information System (INIS)

    Palta, Jatinder R.; Liu, Chihray; Li, Jonathan G.

    2008-01-01

    The traditional prescriptive quality assurance (QA) programs that attempt to ensure the safety and reliability of traditional external beam radiation therapy are limited in their applicability to such advanced radiation therapy techniques as three-dimensional conformal radiation therapy, intensity-modulated radiation therapy, inverse treatment planning, stereotactic radiosurgery/radiotherapy, and image-guided radiation therapy. The conventional QA paradigm, illustrated by the American Association of Physicists in Medicine Radiation Therapy Committee Task Group 40 (TG-40) report, consists of developing a consensus menu of tests and device performance specifications from a generic process model that is assumed to apply to all clinical applications of the device. The complexity, variation in practice patterns, and level of automation of high-technology radiotherapy renders this 'one-size-fits-all' prescriptive QA paradigm ineffective or cost prohibitive if the high-probability error pathways of all possible clinical applications of the device are to be covered. The current approaches to developing comprehensive prescriptive QA protocols can be prohibitively time consuming and cost ineffective and may sometimes fail to adequately safeguard patients. It therefore is important to evaluate more formal error mitigation and process analysis methods of industrial engineering to more optimally focus available QA resources on process components that have a significant likelihood of compromising patient safety or treatment outcomes

  10. 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)

  11. 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

  12. Quality assurance of external exposure measurement for national survey of environmental natural radioactive level

    International Nuclear Information System (INIS)

    Yue Qingyu

    1995-01-01

    This paper summarizes the quality assurance work of external exposure measurement for national survey of environmental natural radioactive level. It mainly introduces instrumentation used in external exposure measurement and its properties, the measurement results of three times of national in-site intercomparison, and in-site sample check results of measurement results from 29 provinces, cities and autonomous regions and Wuhan, Baotou cities

  13. Harsh Parenting and Child Externalizing Behavior: Skin Conductance Level Reactivity as a Moderator

    Science.gov (United States)

    Erath, Stephen A.; El-Sheikh, Mona; Cummings, E. Mark

    2009-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting and child externalizing behavior. Participants were 251 boys and girls (8-9 years). Mothers and fathers provided reports of harsh parenting and their children's externalizing behavior; children also provided reports of harsh parenting.…

  14. Skin Conductance Level Reactivity Moderates the Association between Harsh Parenting and Growth in Child Externalizing Behavior

    Science.gov (United States)

    Erath, Stephen A.; El-Sheikh, Mona; Hinnant, J. Benjamin; Cummings, E. Mark

    2011-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting at age 8 years and growth in child externalizing behavior from age 8 to age 10 (N = 251). Mothers and fathers provided reports of harsh parenting and their children's externalizing behavior; children also provided reports of harsh…

  15. Ionizing secondary radiation generated by analog radiological and digital coronary cine angiographic equipment. Influence of external protection devices

    International Nuclear Information System (INIS)

    Ramirez N, Alfredo; Farias Ch, Eric; Silva J, Ana Maria; Leyton L, Fernando; Oyarzun C, Carlos; Ugalde P, Hector; Dussaillant, Gaston; Cumsille G, Angel

    2000-01-01

    Exposure to ionizing radiation is a know hazard of radiological procedures. Aim: to compare the emission of secondary ionizing radiation from two coronary angiographic equipments, one with digital and the other with analog image generation. To evaluate the effectiveness of external radiological protection devices. Material and methods: environmental and fluoroscopy generated radiation in the cephalic region of the patient was measured during diagnostic coronary angiographies. Ionizing radiation generated in anterior left oblique protection (ALO) and anterior right oblique protection (ARO) were measured with and without leaded protections. In 19 patients (group 1), a digital equipment was used and in 21 (group 2), an analog equipment. Results: header radiation for group 1 and 2 was 1194±337 and 364±222 μGray/h respectively (p≤0.001). During fluoroscopy and with leaded protection generated radiation for groups 1 and 2 was 612±947 and 70±61μGray/h respectively (p≤0.001). For ALO projection, generated for groups 1 and 2 was 105±47 and 71±192 μGray/h respectively (p≤0.001). During filming the radiation for ALO projection for groups 1 and 2 was 7252±9569 and 1671±2038 μGray/h respectively (p=0.03). Out of the protection zone, registered radiation during fluoroscopy for groups 1 and 2 was 2800±1741 and 1318±954 μGray/h respectively (p≤0.001); during filming, the figures were 15500±5840 and 18961±10599 μGray/h respectively (NS). Conclusions: digital radiological equipment has a lower level of ionizing radiation emission than the analog equipment

  16. Radiation and man - evaluation of biological and environmental low level radiation effects

    International Nuclear Information System (INIS)

    Riklis, E.

    1977-01-01

    The harmful effects of acute radiation cannot be resolved by statistical means and require clearer knowledge of mechanisms of action and much wider collection of human experience before any definite sound stand can be taken. Much information has accumulated from animal experiments, and still the interpretations are not always clearcut, but for human experience it is only the occasional accident which can give a direct answer. Some of the phenomena attributed to low dose radiation are summarized. There are regions of radiation exposure about which we have only limited positive knowledge, an all low-dose risk estimates have been based on effects observed at relatively high doses. Much information has been gathered which does not support the severity of former basic principles, especially our knowledge of mechanisms of repair existing in most cells as natural defence against the damages caused by radiation as well as by many chemicals which act as mutagenic and carcinogenic agents. Understanding these mechanism, their scope of action and their availability to a damaged cell and organism will lead towards modification of the acceptable permissible exposures, in some cases towards severity, but in most cases towards leniency and higher values. For the evaluation of the effects of low level low dose-rate radiations, whether external, or from internal deposition of isotopes, only late somatic and genetic effects should be considered. (B.G.)

  17. 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

  18. Low-level radiation and cancer deaths

    International Nuclear Information System (INIS)

    Sanders, B.S.

    1978-01-01

    It is stated that although the proportion of cancer deaths among males is somewhat higher for Hanford employees with recorded occupational radiation exposure compared with males in the general population of the State of Washington, there is no indication that radiation is the cause of this difference. Statistics are given for mean doses received and for deaths from cancer and other causes for male employees. It is shown that for each year the mean dose level of those who died from cancer is not significantly different from the mean of those who died from other causes. The mean dose level for the majority of those who died in a specific year is lower than the mean for the survivors in the year of death, in the year preceding the year of death, or in the two years preceding the year of death. This is true whether the mean was for those dying from cancer or from other causes. These relationships are similar for female exposed employees and agree with other similar studies. The latest analysis on longevity of exposed male Hanford employees vs those nonexposed and the out-of-plant controls from date of hire to April 1974 are considered and show no firm indication of any lasting adverse health effects among employees attributable to occupational exposure to radiation within permissible limits. (U.K.)

  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. Mortality from internal and external radiation exposure in a cohort of male German uranium millers, 1946-2008

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, M.; Dufey, F.; Schnelzer, M.; Sogl, M.; Walsh, L. [Federal Office for Radiation Protection, Neuherberg (Germany). Dept. of Radiation Protection and Health; Laurier, D. [Institute for Radiological Protection and Nuclear Safety (IRSN), Paris (France); Nowak, D. [LMU Muenchen (Germany). Inst. for Occupational Medicine and Environmental Medicine; Marsh, J.W. [Public Health England, Chilton, Didcot (United Kingdom)

    2015-05-15

    To examine exposure-response relationships between ionizing radiation and several mortality outcomes in a subgroup of 4,054 men of the German uranium miner cohort study, who worked between 1946 and 1989 in milling facilities, but never underground or in open pit mines. Mortality follow-up was from 1946 to 2008, accumulating 158,383 person-years at risk. Cumulative exposure to radon progeny in working level months (WLM) (mean = 8, max = 127), long-lived radionuclides from uranium ore dust in kBqh/m{sup 3} (mean = 3.9, max = 132), external gamma radiation in mSv (mean = 26, max = 667) and silica dust was estimated by a comprehensive job-exposure matrix. Internal Poisson regression models were applied to estimate the linear excess relative risk (ERR) per unit of cumulative exposure. Overall, a total of 457, 717 and 111 deaths occurred from malignant cancer, cardiovascular diseases and non-malignant respiratory diseases, respectively. Uranium ore dust and silica dust were not associated with mortality from any of these disease groups. A statistically significant relationship between cumulative radon exposure and mortality from all cancers (ERR/100 WLM = 1.71; p = 0.02), primarily due to lung cancer (n = 159; ERR/100 WLM = 3.39; p = 0.05), was found. With respect to cumulative external gamma radiation, an excess of mortality of solid cancers (n = 434; ERR/Sv = 1.86; p = 0.06), primarily due to stomach cancer (n = 49, ERR/Sv = 10.0; p = 0.12), was present. The present findings show an excess mortality from lung cancer due to radon exposure and from solid cancers due to external gamma radiation in uranium millers that was not statistically significant. Exposure to uranium was not associated with any cause of death, but absorbed organ doses were estimated to be low.

  1. Mortality from internal and external radiation exposure in a cohort of male German uranium millers, 1946-2008

    International Nuclear Information System (INIS)

    Kreuzer, M.; Dufey, F.; Schnelzer, M.; Sogl, M.; Walsh, L.; Nowak, D.

    2015-01-01

    To examine exposure-response relationships between ionizing radiation and several mortality outcomes in a subgroup of 4,054 men of the German uranium miner cohort study, who worked between 1946 and 1989 in milling facilities, but never underground or in open pit mines. Mortality follow-up was from 1946 to 2008, accumulating 158,383 person-years at risk. Cumulative exposure to radon progeny in working level months (WLM) (mean = 8, max = 127), long-lived radionuclides from uranium ore dust in kBqh/m 3 (mean = 3.9, max = 132), external gamma radiation in mSv (mean = 26, max = 667) and silica dust was estimated by a comprehensive job-exposure matrix. Internal Poisson regression models were applied to estimate the linear excess relative risk (ERR) per unit of cumulative exposure. Overall, a total of 457, 717 and 111 deaths occurred from malignant cancer, cardiovascular diseases and non-malignant respiratory diseases, respectively. Uranium ore dust and silica dust were not associated with mortality from any of these disease groups. A statistically significant relationship between cumulative radon exposure and mortality from all cancers (ERR/100 WLM = 1.71; p = 0.02), primarily due to lung cancer (n = 159; ERR/100 WLM = 3.39; p = 0.05), was found. With respect to cumulative external gamma radiation, an excess of mortality of solid cancers (n = 434; ERR/Sv = 1.86; p = 0.06), primarily due to stomach cancer (n = 49, ERR/Sv = 10.0; p = 0.12), was present. The present findings show an excess mortality from lung cancer due to radon exposure and from solid cancers due to external gamma radiation in uranium millers that was not statistically significant. Exposure to uranium was not associated with any cause of death, but absorbed organ doses were estimated to be low.

  2. 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)

  3. 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....

  4. 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.

  5. 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

  6. 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.

  7. Mercure IV code application to the external dose computation from low and medium level wastes

    International Nuclear Information System (INIS)

    Tomassini, T.

    1985-01-01

    In the present work the external dose from low and medium level wastes is calculated using MERCURE IV code. The code utilizes MONTECARLO method for integrating multigroup line of sight attenuation Kernels

  8. Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

    International Nuclear Information System (INIS)

    Morishima, Hiroshige; Koga, Taeko; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

    2000-01-01

    As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. A good correlation was observed between the dose assessed indirectly and that measured directly and the

  9. Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

    Energy Technology Data Exchange (ETDEWEB)

    Morishima, Hiroshige; Koga, Taeko [Kinki Univ., Higashi-Osaka, Osaka (Japan). Atomic Energy Research Inst.; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

    2000-10-01

    As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. A good correlation was observed between the dose assessed indirectly and that measured directly and the

  10. 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

  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. Assessment of background gamma radiation levels around Tummalapalle uranium mining and processing facility, Andhra Pradesh

    International Nuclear Information System (INIS)

    Rana, B.K.; Dhumale, M.R.; Molla, Samim; Rao, K.B.; Jha, S.K.; Tripathi, R.M.; Sahu, S.K.

    2018-01-01

    Natural environmental radioactivity and the associated external exposure due to gamma radiation depend primarily on the geological and geographical conditions, and appear at different levels in the soil of each region in the world. The dose received by the population in a region comprises of (i) external gamma radiation dose due to cosmic rays and primordial radionuclides; (ii) inhalation dose due to radon, thoron and their progeny, and (iii) ingestion dose due to the intake of radionuclides through the consumption of food, milk, water, etc. In this study, background gamma radiation level around Tummalapalle uranium mining and processing site was estimated by using radiation survey meter and deploying environmental TLDs. The generated data can be served as baseline for this area for future comparison for prolonged operation of the plant, for the upcoming adjacent projects and during decommissioning phase of the mine, mill and tailings pond

  13. 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)

  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. Effects of external radiation in a co-culture model of endothelial cells and adipose-derived stem cells

    International Nuclear Information System (INIS)

    Haubner, Frank; Leyh, Michaela; Ohmann, Elisabeth; Pohl, Fabian; Prantl, Lukas; Gassner, Holger G

    2013-01-01

    The inflammatory response clinically observed after radiation has been described to correlate with elevated expression of cytokines and adhesion molecules by endothelial cells. Therapeutic compensation for this microvascular compromise could be an important approach in the treatment of irradiated wounds. Clinical reports describe the potential of adipose-derived stem cells to enhance wound healing, but the underlying cellular mechanisms remain largely unclear. Human dermal microvascular endothelial cells (HDMEC) and human adipose-derived stem cells (ASC) were cultured in a co-culture setting and irradiated with sequential doses of 2 to 12 Gy. Cell count was determined 48 h after radiation using a semi-automated cell counting system. Levels of interleukin-6 (IL-6), basic fibroblast growth factor (FGF), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were determined in the supernatants using enzyme-linked immunosorbent assay (ELISA). Irradiated HDMEC and ASC as well as non-irradiated co-cultures, HDMEC or ASC respectively were used as controls. Cell count was significantly reduced in irradiated co-cultures of HDMEC and ASC compared to non-irradiated controls. Levels of IL-6, FGF, ICAM-1 and VCAM-1 in the supernatants of the co-cultures were significantly less affected by external radiation in comparison to HDMEC. The increased expression of cytokines and adhesion molecules by HDMEC after external radiation is mitigated in the co-culture setting with ASC. These in vitro changes seem to support the clinical observation that ASC may have a stabilizing effect when injected into irradiated wounds

  17. 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

  18. 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

  19. 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

  20. The hazards of low-level radiation

    International Nuclear Information System (INIS)

    Blackith, R.

    1979-01-01

    Safety standards are questioned, particularly in relation to the risk of inducing cancer at low doses of radiation. Statements are made on the following topics: incidence of leukaemia among children around reactors, general aging effect due to radiation, leukaemia among radiation workers in a shipyard repairing nuclear submarines, official withdrawal of funds from research workers in the field of radiation hazards, discrepancies between different measurements of radiation near nuclear power plants. (U.K.)

  1. 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...

  2. 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)

  3. Dose measurement, its distribution and individual external dose assessments of inhabitants on high background radiation area in China

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Taeko; Morishima, Hiroshige [Kinki Univ., Atomic Energy Research Institute, Osaka (Japan); Tatsumi, Kusuo [Kinki Univ., Life Science Research Institute, Osaka (Japan); Nakai, Sayaka; Sugahara, Tsutomu [Health Research Foundation, Kyoto (Japan); Yuan Yongling [Labor Hygiene Institute of Hunan Prov. (China); Wei Luxin [Laboratory of Industorial Hygiene, Ministry of Health (China)

    2001-01-01

    As a part of the China-Japan cooperative research on the natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external to natural radiation in the high background radiation area (HBRA) of Yangjiang in Guangdong province and in the control area (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by the personal dosimeters, an indirect method was applied to estimate the exposed dose rates from the environmental radiation dose rates measured by survey meters and the occupancy factors of each hamlet. An individual radiation dose roughly correlates with the environmental radiation dose and the life style of the inhabitant. We have analyzed the environmental radiation doses in the hamlets and the variation of the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and the several hamlets of the different level doses in HBRA and Hampizai hamlet in CA. With these parameters, we made estimations of individual dose rates and compared them with those obtained from the direct measurement using dosimeters carried by selected individuals. The results obtained are as follows: (1) The environmental radiation dose rates are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiation. The indoor radiation dose rates were due to the exposure from the natural radioactive nuclides in the building materials and they were about twice higher than the outdoor radiation dose rates. This difference was not observed in CA. (2) The occupancy factor was affected by the age of individuals and the seasons of a year. Indoor occupancy factors were higher for infants and aged individuals than for other age groups. This lead to higher

  4. Dose measurement, its distribution and individual external dose assessments of inhabitants on high background radiation area in China

    International Nuclear Information System (INIS)

    Koga, Taeko; Morishima, Hiroshige; Tatsumi, Kusuo; Nakai, Sayaka; Sugahara, Tsutomu; Yuan Yongling; Wei Luxin

    2001-01-01

    As a part of the China-Japan cooperative research on the natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external to natural radiation in the high background radiation area (HBRA) of Yangjiang in Guangdong province and in the control area (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by the personal dosimeters, an indirect method was applied to estimate the exposed dose rates from the environmental radiation dose rates measured by survey meters and the occupancy factors of each hamlet. An individual radiation dose roughly correlates with the environmental radiation dose and the life style of the inhabitant. We have analyzed the environmental radiation doses in the hamlets and the variation of the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and the several hamlets of the different level doses in HBRA and Hampizai hamlet in CA. With these parameters, we made estimations of individual dose rates and compared them with those obtained from the direct measurement using dosimeters carried by selected individuals. The results obtained are as follows: 1) The environmental radiation dose rates are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiation. The indoor radiation dose rates were due to the exposure from the natural radioactive nuclides in the building materials and they were about twice higher than the outdoor radiation dose rates. This difference was not observed in CA. 2) The occupancy factor was affected by the age of individuals and the seasons of a year. Indoor occupancy factors were higher for infants and aged individuals than for other age groups. This lead to higher

  5. Skin Conductance Level Reactivity Moderates the Association Between Harsh Parenting and Growth in Child Externalizing Behavior

    OpenAIRE

    Erath, Stephen A.; El-Sheikh, Mona; Hinnant, J. Benjamin; Cummings, E. Mark

    2011-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting at age 8 years and growth in child externalizing behavior from age 8 to age 10 (N = 251). Mothers and fathers provided reports of harsh parenting and their children’s externalizing behavior; children also provided reports of harsh parenting. SCLR was assessed in response to a socioemotional stress task and a problem-solving challenge task. Latent growth modeling revealed that boys w...

  6. Harsh Parenting and Child Externalizing Behavior: Skin Conductance Level Reactivity as a Moderator

    OpenAIRE

    Erath, Stephen A.; El-Sheikh, Mona; Cummings, E. Mark

    2009-01-01

    Skin conductance level reactivity (SCLR) was examined as a moderator of the association between harsh parenting and child externalizing behavior. Participants were 251 boys and girls (8–9 years). Mothers and fathers provided reports of harsh parenting and their children’s externalizing behavior; children also provided reports of harsh parenting. SCLR was assessed in response to a socioemotional stress task and a problem-solving challenge task. Regression analyses revealed that the association...

  7. 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)

  8. Radiation levels in Ecuadorian Cattle Milk

    International Nuclear Information System (INIS)

    Reinoso, Teresa; Vasquez, Ramiro

    2008-01-01

    Full text: The radiation and natural radioactivity present in the ground from a radioactive decay of 238 U, 235 U and 232 Th, and of the radioisotope 40 K can be transferred to the nutritional chain of the human being. Milk is a food considered basic within population's diet. The Ecuadorian Highlands has the greater production of cattle milk in the country, this industry needs great extensions of graze and available superficial water, which the cows consumed for crude milk production, with the consequent product industrialization. In the present research, gamma radiation levels where monitoring in 12 crude milk representative samples of the zone. The measurements where carried out using an equipment of spectrometry gamma ray system, with a detector of Hiperpuro Germanium (GeHp), which has been used in the analysis of standard and samples spectrums, with a constant geometry of the sample holder. The spectrums of the milk analysis show the presence of the radioisotopes coming from uranium radioactive decay. The majority of the values of activity concentration are below the minimum detection activity, unlike the potassium that presents a detectable but a non quantitative spectrum. So far, with the results obtained it is possible to guarantee the milk consumption and its derivatives in the Andean Region of the country. Related research will allow us implementing the radiological monitoring of this and other foods in the country, in order to protected population health. (author)

  9. Beam size measurement at high radiation levels

    International Nuclear Information System (INIS)

    Decker, F.J.

    1991-05-01

    At the end of the Stanford Linear Accelerator the high energy electron and positron beams are quite small. Beam sizes below 100 μm (σ) as well as the transverse distribution, especially tails, have to be determined. Fluorescent screens observed by TV cameras provide a quick two-dimensional picture, which can be analyzed by digitization. For running the SLAC Linear Collider (SLC) with low backgrounds at the interaction point, collimators are installed at the end of the linac. This causes a high radiation level so that the nearby cameras die within two weeks and so-called ''radiation hard'' cameras within two months. Therefore an optical system has been built, which guides a 5 mm wide picture with a resolution of about 30 μm over a distance of 12 m to an accessible region. The overall resolution is limited by the screen thickness, optical diffraction and the line resolution of the camera. Vibration, chromatic effects or air fluctuations play a much less important role. The pictures are colored to get fast information about the beam current, size and tails. Beside the emittance, more information about the tail size and betatron phase is obtained by using four screens. This will help to develop tail compensation schemes to decrease the emittance growth in the linac at high currents. 4 refs., 2 figs

  10. External gamma radiation and mortality from cardiovascular diseases in the German WISMUT uranium miners cohort study, 1946-2008

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, M.; Dufey, F.; Sogl, M.; Schnelzer, M.; Walsh, L. [Federal Office for Radiation Protection, Department of Radiation Protection and Health, Neuherberg (Germany)

    2013-03-15

    It is currently unclear whether exposure of the heart and vascular system, at lifetime accumulated dose levels relevant to the general public (<500 mGy), is associated with an increased risk of cardiovascular disease. Therefore, data from the German WISMUT cohort of uranium miners were investigated for evidence of a relationship between external gamma radiation and death from cardiovascular diseases. The cohort comprises 58,982 former employees of the Wismut company. There were 9,039 recorded deaths from cardiovascular diseases during the follow-up period from 1946 to 2008. Exposures to external gamma radiation were estimated using a detailed job-exposure matrix. The exposures were based on expert ratings for the period 1946-1954 and measurements thereafter. The excess relative risk (ERR) per unit of cumulative gamma dose was obtained with internal Poisson regression using a linear ERR model with baseline stratification by age and calendar year. The mean cumulative gamma dose was 47 mSv for exposed miners (86 %), with a maximum of 909 mSv. No evidence for an increase in risk with increasing cumulative dose was found for mortality from all cardiovascular diseases (ERR/Sv = -0.13; 95 % confidence interval (CI): -0.38; 0.12) and ischemic heart diseases (n = 4,613; ERR/Sv = -0.03; 95 % CI: -0.38, 0.32). However, a statistically insignificant increase (n = 2,073; ERR/Sv = 0.44; 95 % CI: -0.16, 1.04) for mortality from cerebrovascular diseases was observed. Data on smoking, diabetes, and overweight are available for subgroups of the cohort, indicating no major correlation with cumulative gamma radiation. Confounding by these factors or other risk factors, however, cannot be excluded. In conclusion, the results provide weak evidence for an increased risk of death due to gamma radiation only for cerebrovascular diseases. (orig.)

  11. 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

  12. 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)

  13. Modelling population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Emilie [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Alonzo, Frederic, E-mail: frederic.alonzo@irsn.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Garcia-Sanchez, Laurent [Laboratoire de biogeochimie, biodisponibilite et transferts des radionucleides (L2BT) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Beaugelin-Seiller, Karine; Garnier-Laplace, Jacqueline [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France)

    2012-07-01

    We modelled population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions. We used Leslie matrices to combine life-history characteristics (duration of life stages, survival and fecundity rates) and dose rate-response curves for hatching, survival and reproduction fitted on effect data from the FREDERICA database. Changes in net reproductive rate R{sub 0} (offspring per individual) and asymptotic population growth rate {lambda} (dimensionless) were calculated over a range of dose rates in two marine polychaetes (Neanthes arenaceodentata and Ophryotrocha diadema) and a freshwater gastropod (Physa heterostropha). Sensitivities in R{sub 0} and {lambda} to changes in life-history traits were analysed in each species. Results showed that fecundity has the strongest influence on R{sub 0}. A delay in age at first reproduction is most critical for {lambda} independent of the species. Fast growing species were proportionally more sensitive to changes in individual endpoints than slow growing species. Reduction of 10% in population {lambda} were predicted at dose rates of 6918, 5012 and 74,131 {mu}Gy{center_dot}h{sup -1} in N. arenaceodentata, O. diadema and P. heterostropha respectively, resulting from a combination of strong effects on several individual endpoints in each species. These observations made 10%-reduction in {lambda} a poor criterion for population protection. The lowest significant changes in R{sub 0} and {lambda} were respectively predicted at a same dose rate of 1412 {mu}Gy h{sup -1} in N. arenaceodentata, at 760 and 716 {mu}Gy h{sup -1} in O. diadema and at 12,767 and 13,759 {mu}Gy h{sup -1} in P. heterostropha. These values resulted from a combination of slight but significant changes in several measured endpoints and were lower than effective dose rates calculated for the individual level in O. diadema and P. heterostropha. The relevance of the experimental dataset (external irradiation rather

  14. 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

  15. 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)

  16. Effects of Managers’ Work Motivation and Networking Activity on Their Reported Levels of External Red Tape

    NARCIS (Netherlands)

    Torenvlied, R.; Akkerman, A.

    2012-01-01

    This study brings together two perspectives on managers’ reported levels of red tape. The work motivation perspective explains how managers’ characteristics, such as work engagement (alienation) or commitment, affect their reported levels of red tape. The external control perspective explains how

  17. 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.

  18. 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)

  19. 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

  20. 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.)

  1. 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

  2. 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).

  3. 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.)

  4. 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).

  5. Federal guidelines for estimating external exposure of radiation workers in Russia

    International Nuclear Information System (INIS)

    Chizhov, K.; Kryuchkov, V.; Mark, N.K.; Szoeke, I.; Sneve, M.K.

    2017-01-01

    In this paper, an overview of Russian federal guidelines for optimizing work procedures in terms of radiation protection for planned field work is presented. The general provisions, procedures and methods for applying the principles of optimization are provided in accordance with the Radiation Safety Standards (NRB-99/2009) and Basic sanitary rules of radiation safety (OSPORB-99/2010). Jobs in environments with actual or potential radiation hazards shall be planned on the basis of the principle of optimization in order to prevent unexpected exposure of the personnel. Control and optimization of dose to workers is a continuous process, which is carried out at various stages of radiation-hazardous work under constant involvement of the personnel in the planning procedure. Implementation of the principle of optimization should include considerations for human and organizational aspects for ensuring high level safety. The planning and optimization process includes education and training of personnel, estimation of radiation doses for the upcoming work, preparations for unplanned situations, and implementation of practical safety measures within the targeted radiation-hazardous works. The optimization principle is most important in the planning phase where uncertainties in planned exposure must be considered. Variability of radiation risks related to different scenarios (choices) can be managed by modern simulation technology, and use of advanced tools (software) for simulating planned activities and conditions in digital models including the environment (premises of an industrial complex) with dynamic visualization of the radiation exposure conditions. Existing hardware and emerging information technologies allow practical application of such techniques. Application of advanced information technology can reduce uncertainties related to the radiation environment by turning invisible radiation into directly perceivable risk information. In addition, virtual reality

  6. 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.)

  7. 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.

  8. 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

  9. Terrestrial radiation level in selected asphalt plants in Port Harcourt ...

    African Journals Online (AJOL)

    Terrestrial radiation level in selected asphalt plants in Port Harcourt, Nigeria. ... An environmental radiation survey in asphalt processing plants in Rivers State was been carried out ... Therefore the results show significant radiological risk.

  10. 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...

  11. 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

  12. Radiation sources, radiation environment and risk level at Dubna

    International Nuclear Information System (INIS)

    Komochkov, M.M.

    1991-01-01

    The overall information about ionizing radiation sources, which form radiation environment and risk at Dubna, is introduced. Systematization of the measurement results is performed on the basis of the effective dose and losses of life expectancy. The contribution of different sources to total harm of Dubna inhabitants has been revealed. JINR sources carry in ∼ 4% from the total effective dose of natural and medicine radiation sources; the harm from them is much less than the harm from cigarette smoking. 18 refs.; 2 tabs

  13. Infant attachment disorganization and moderation pathways to level and change in externalizing behavior during preschool ages.

    Science.gov (United States)

    Wang, Feihong; Willoughby, Michael; Mills-Koonce, Roger; Cox, Martha J

    2016-12-01

    This research examined the child, parent, and family conditions under which attachment disorganization was related to both level and change in externalizing behavior during preschool among a community sample. Using the ordinary least squares regression, we found that attachment disorganization at 12 months significantly predicted children's externalizing behavior at 36 months and this prediction was not contingent on any other factors tested. For predicting changes in externalizing behavior from 36 to 60 months, we found a significant main effect of family cumulative risk and an interaction effect between attachment disorganization at 12 months and maternal sensitivity at 24 months. Specifically, high disorganization was related to a significant decrease in externalizing behavior from 36 to 60 months when maternal sensitivity at 24 months was high. Our main-effect findings replicated the significant effect of attachment disorganization and cumulative risk on externalizing behavior with preschool-aged children. Our interaction finding provided support for understanding the parenting conditions under which infant attachment disorganization may be related to change in externalizing behavior during preschool ages. Implications of the findings were discussed.

  14. 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

  15. Comparison between radioimmunotherapy and external beam radiation therapy for patients with hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Zhao-Chong [Department of Radiation Oncology, Zhongshan Hospital, Fudan University, 136 Yi Xue Yuan Road, Shanghai, 200032 (China); Tang, Zhao-You; Yang, Bing-Hui; Liu, Kang-Da; Wu, Zhi-Quan; Fan, Jia; Qin, Lun-Xiu; Sun, Hui-Chuan; Zhou, Jian [Liver Cancer Institute, Fudan University, Shanghai (China); Jiang, Guo-Liang [Department of Radiation Oncology, Cancer Hospital. Fudan University, Shanghai (China)

    2002-12-01

    It has previously been observed in animal studies that, at equivalent doses, radioimmunotherapy (RIT) is 2.5 times more effective than multiple fractions of external beam radiation therapy (EBRT) in inhibiting tumour growth. In this study, we compared the use of RIT and EBRT in patients with hepatocellular carcinoma (HCC), treated during the past 10 years. Of 67 patients without extrahepatic involvement, 32 were treated with hepatic artery ligation combined with RIT (the RIT group) while 35 were treated with a combination of hepatic arterial chemo-embolisation and EBRT (the EBRT group). The patients in the RIT group received {sup 131}I-Hepama-1 monoclonal antibody, which was infused through the hepatic artery catheter. The patients in the EBRT group received transcatheter arterial chemo-embolisation and limited-field EBRT using a linear accelerator. Parameters observed include tumour response, alpha-fetoprotein (AFP) level in serum, human anti-murine antibody (HAMA) assay, T lymphocyte subsets, survival rates, routine parameters, sequential resection rates and histopathological status of the resection specimens. The sequential resection rates were 53% (17/32) and 23% (8/35), and tumour response rates were 72% (23/32) and 86% (30/35) in the RIT and EBRT groups, respectively. The main side-effects in the RIT group were mild allergic reactions. The most common toxicity in the EBRT group was an increase in liver enzymes. The liver tissue in the target volume was injured by EBRT. The injured liver tissue revealed a low-attenuation area adjacent to the hepatic tumour within the target volume on follow-up computed tomography studies after EBRT. On pathological evaluation, the low-attenuation area revealed hyperaemia, distended hepatic sinusoids packed with erythrocytes and hepatic cell loss. The sequential resection specimens from both the RIT and the EBRT group showed residual cancer tissue located at the edge of the mass. The residual cancer cells presented as giant

  16. 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

  17. 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

  18. Radiation doses and possible radiation effects of low-level, chronic radiation in vegetation

    International Nuclear Information System (INIS)

    Rhoads, W.A.; Franks, L.A.

    1975-01-01

    Measurements were made of radiation doses in soil and vegetation in Pu-contaminated areas at the Nevada Test Site with the objective of investigating low-level, low-energy gamma radiation (with some beta radiation) effects at the cytological or morphological level in native shrubs. In this preliminary investigation, the exposure doses to shrubs at the approximate height of stem apical meristems were estimated from 35 to 140 R for a ten-year period. The gamma exposure dose estimated for the same period was 20.7 percent +- 6.4 percent of that recorded by the dosimeters used in several kinds of field instrument surveys. Hence, a survey instrument reading made at about 25 cm in the tops of shrubs should indicate about 1 / 5 the dosimeter-measured exposures. No cytology has yet been undertaken because of the drought since last winter. (auth)

  19. 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

  20. Low-level radiation: a high-level concern

    International Nuclear Information System (INIS)

    Holden, C.

    1979-01-01

    The role of DOE in radiation health effects research is discussed. The possibility of conflict of interest is presented. The Mancuso episode is cited as evidence. The roles of several agencies (EPA, NRC, and OSHA) in establishing safe limits of radiation exposure are discussed

  1. Background radiation levels and medical exposure levels in Australia

    International Nuclear Information System (INIS)

    Webb, D.V.; Solomon, S.B.; Thomson, J.E.M.

    1999-01-01

    The average effective background dose received by the Australian population has been reassessed to be ∼1.5 millisievert (mSv) per year. Over half of this exposure arises from exposure from terrestrial radiation and cosmic rays, the remainder from radionuclides within the body and from inhalation of radon progeny. This background is to be compared with medical radiation, primarily diagnostic, which could add half as much again to the population exposure. This paper reviews research programmes carried out by the Australian Radiation Laboratory to study radiation exposure from natural background and from medical use. While the latter exposure is accepted to have a social benefit, there is a need to ensure that doses are no more than necessary to provide effective diagnosis and optimal treatment. Copyright (1999) Australasian Radiation Protection Society Inc

  2. Infant Attachment Disorganization and Moderation Pathways to Level and Change in Externalizing Behavior during Preschool Ages

    Science.gov (United States)

    Wang, Feihong; Willoughby, Michael; Mills-Koonce, Roger; Cox, Martha J.

    2016-01-01

    This research examined the child, parent, and family conditions under which attachment disorganization was related to both level and change in externalizing behavior during preschool among a community sample. Using the ordinary least squares regression, we found that attachment disorganization at 12 months significantly predicted children's…

  3. 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)

  4. 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

  5. External hazards analysis approach to level 1 PSA of Mochovce NPP - Slovakia

    International Nuclear Information System (INIS)

    Stojka, Tibor

    2000-01-01

    Analyses of external events had been first time performed at the design stage of the Mochovce NPP showing sufficiently low contribution of external hazards to core damage frequency. But, based on IAEA document 'Safety problems of WWER-440/213 NPPs and the categorization' (IAEA-EBP-WWER-03, 1996), the need of new reassessment arose due to discrepancy of some origin recommendations in compare with present IAEA ones. Mochovce NPP Nuclear Safety Improvements Program elaborated at the same time included the IAEA recommendations and following improvements were proposed to perform in context of external events. 1. Seismic project and new locality seismic evaluation This safety improvement includes also some 'on site' technical improvements in seismic stability of structures and equipment. 2. Unit specific analyses of extreme meteorologic conditions. This safety improvement focuses on impact of feasible extreme conditions on NPP systems caused by rain, snow and hail storms, frost, winds, low and high temperatures. 3. Analyses of external hazards caused by humans. In this safety improvement were specified: feasible sources of explosions; analyses of hydrogen, gas and propane-calor gas depots; air crash risk. The results of these implemented safety improvements were considered in the PSA study. The External hazards analysis is also part of Level 1 PSA Mochovce NPP performed by PSA Department of VUJE Trnava Inc., Engineering, Design and Research Organization, Slovakia. Some partial analyses are performed in cooperation with following companies DS and S - SAIC, USA and Geophysical Institute Academy of Science, Slovakia Relko, Slovakia. Basic documents are: NUREG/CR-2300 'PRA Procedures Guide - A Guide to the Performance of Probabilistic Risk Assessments for Nuclear Power Plants' and IAEA SS No. 50-P-7 'Treatment of External Hazards in PSA for NPPs. The external hazards analysis consists of following parts: 1. Geography and plant locality; 2. Nearby industry; 3. Extreme

  6. Treatment of External Levels in Neutron Resonance Fitting: Application to the Nonfissile Nuclide 52Cr

    International Nuclear Information System (INIS)

    Froehner, Fritz H.; Bouland, Olivier

    2001-01-01

    Measured neutron resonance cross sections are usually analyzed and parametrized by fitting theoretical curves to high-resolution point data. Theoretically, the cross sections depend mainly on the 'internal' levels inside the fitted energy range but also on the 'external' levels outside. Although the external levels are mostly unknown, they must be accounted for. If they are simply omitted, the experimental data cannot be fitted satisfactorily. Especially with elastic scattering and total cross-section data, one gets troublesome edge effects and difficulties with the potential cross section between resonances. Various ad hoc approaches to these problems are still being used, involving replacement of the unknown levels by equidistant ('picket fence') or Monte Carlo-sampled resonance sequences, or replication of the internal level sequence; however, more convenient, better working, and theoretically sound techniques have been available for decades. These analytical techniques are reviewed. They describe the contribution of external levels to the R matrix concisely in terms of average resonance parameters (strength function, effective radius, etc.). A more recent, especially convenient approximation accounts for the edge effects by just one fictitious pair of very broad external resonances. Fitting the thermal region, including accurately known thermal cross sections, is often done by adjusting a number of bound levels by trial and error, although again a simple analytical recipe involving just one bound level has been available for a long time. For illustration, these analytical techniques are applied to the resolved resonance region of 52 Cr. The distinction between channel radii and effective radii, crucial in the present context, is emphasized

  7. Effects of Interaural Level and Time Differences on the Externalization of Sound

    DEFF Research Database (Denmark)

    Dau, Torsten; Catic, Jasmina; Santurette, Sébastien

    Distant sound sources in our environment are perceived as externalized and are thus properly localized in both direction and distance. This is due to the acoustic filtering by the head, torso, and external ears, which provides frequency dependent shaping of binaural cues, such as interaural level...... differences (ILDs) and interaural time differences (ITDs). Further, the binaural cues provided by reverberation in an enclosed space may also contribute to externalization. While these spatial cues are available in their natural form when listening to real-world sound sources, hearing-aid signal processing...... is consistent with the physical analysis that showed that a decreased distance to the sound source also reduced the fluctuations in ILDs....

  8. Assessment of dose level of ionizing radiation in army scrap

    International Nuclear Information System (INIS)

    Abdel Hamid, S. M.

    2010-12-01

    Radiation protection is the science of protecting people and the environment from the harmful effects of ionizing radiation, which includes both particle radiation and high energy radiation. Ionizing radiation is widely used in industry and medicine. Any human activity of nuclear technologies should be linked to the foundation of scientific methodology and baseline radiation culture to avoid risk of radiation and should be working with radioactive materials and expertise to understand, control practices in order to avoid risks that could cause harm to human and environment. The study was conducted in warehouses and building of Sudan air force Khartoum basic air force during September 2010. The goal of this study to estimate the radiation dose and measurement of radioactive contamination of aircraft scrap equipment and increase the culture of radiological safety as well as the concept of radiation protection. The results showed that there is no pollution observed in the contents of the aircraft and the spire part stores outside, levels of radiation dose for the all contents of the aircraft and spire part within the excitable level, except temperature sensors estimated radiation dose about 43 μSv/h outside of the shielding and 12 μSv/h inside the shielding that exceeded the internationally recommended dose level. One of the most important of the identification of eighteen (18) radiation sources used in temperature and fuel level sensors. These are separated from the scrap, collected and stored in safe place. (Author)

  9. Health aspects of low-level radiation

    International Nuclear Information System (INIS)

    Marko, A.M.

    1979-06-01

    A brief description of natural background radiation is given. To understand the relationship between doses and effects the magnitude and distribution over time are stressed. The derivation of radiation protection standards and corresponding risks are discussed. The risks to the occupational worker and to the public from nuclear power are placed in context of risks in other industries and from alternate energy sources, including conservation. (author)

  10. Sweating under pressure: skin conductance level reactivity moderates the association between peer victimization and externalizing behavior.

    Science.gov (United States)

    Gregson, Kim D; Tu, Kelly M; Erath, Stephen A

    2014-01-01

    This study examined whether the association between peer victimization and externalizing behavior may be illuminated by individual differences in skin conductance level reactivity (SCLR) in the context of peer stress. Participants included 123 fifth and sixth graders (Mean age = 12.03 years, 50% females; 42% ethnic minorities). SCLR was assessed in the context of an ecologically relevant, lab-based peer-evaluative stress experience in preadolescence. As hypothesized, self-reported peer victimization was linked with parent- and teacher-reported externalizing behavior, and SCLR consistently moderated these associations. Peer victimization was associated with parent- and teacher-reported externalizing behavior among preadolescents who exhibited lower SCLR, but not among preadolescents who exhibited higher SCLR. Results suggest that promoting engagement with peer stress experiences and enhancing inhibitory control are potential intervention targets that may reduce externalizing behavior in the context of peer victimization (or reduce peer victimization among preadolescents who exhibit externalizing behavior). © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.

  11. 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

  12. 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

  13. 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

  14. 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

  15. 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

  16. Influence of external radiation on non-LTE opacities of Xe

    Science.gov (United States)

    Klapisch, Marcel; Busquet, Michel

    2010-11-01

    In Laboratory Astrophysics, where astrophysics phenomena are scaled down to the laboratory, Xenon is commonly used. In most cases, astrophysical plasmas are not dense enough to warrant LTE. However, they are surrounded by radiation fields. Extensive detailed level computations of non-LTE Xe around Te = 100eV were performed with HULLAC [1], with different radiation temperatures and/or dilution factors. Generally, the effects are very important, even with small dilution factors. [4pt] [1] M. Klapisch and M. Busquet, High Ener. Dens. Phys.5, (2009) 105-9; Bull. Am. Phys. Soc.54, (2009) 210.

  17. Nuclear power and low level radiation hazards

    International Nuclear Information System (INIS)

    Myers, D.K.; Newcombe, H.B.

    1979-03-01

    Even in the future, nuclear power is expected to contribute less than 1/10th of the present total population exposure to man-made radiation. By the best estimates available, the current health risks of nuclear power generation appear to be much less than those associated with the major alternative sources of energy, with the exception of natural gas which is about equally safe. Uncertainties concerning the radiation risks from nuclear power, from medical x-rays and from the effects of reduced ventillation to conserve heat appear to be less than those associated with estimates of risks from the use of coal and various other sources of energy. This is in part because of the large amount of effort devoted to studies of radiation effects. The benefits in terms of current life expectancy associated with any of the conventional or unconventional methods of power production appear to greatly outweigh the associated current health hazards. (author)

  18. A knowledge and awareness level survey of radiation protection among the radiation workers in Henan Province

    International Nuclear Information System (INIS)

    Cheng, Xiao-jun; Tian, Chong-bin; Zhang, Qin-fu; Liu, Cheng; Ding, Li

    2008-01-01

    Full text: Objective: To reveal the knowledge and awareness level of radiation protection among radiation workers in Henan province and to explore the methods to improve it. Methods: A questionnaire survey was carried out among 208 radiation workers. Results: The correct rate of the answer to radiation protection knowledge from radiation workers in Henan province is 53.78%. Most of them (88.9%) realized that it is important to protect patients and their companions. They adhere to the principles of justification of medial exposure and optimization of radiation protection and follow the management system of radiation protection. However, a few workers didn't follow the principles strictly. Sometime, during the radio diagnosis and radiotherapy services, the patients and their companions were not well protected from the radiation, and some patients were given unnecessary X-ray examine. Even worse, some workers did not attach importance to the regulations of radiation protection and disobey them frequently. Again, some hospital leaders disregard the regulation of radiation protection and didn't follow the regulation of health surveillance and radiation protection monitoring properly. And those behaviors and attitude, in fact, influence some workers' attitude to radiation protection. Conclusion: The level of radiation protection knowledge and awareness among the radiation workers in Henan province needs to be improved. It is necessary to strengthen radiation protection knowledge by strengthening training, and to improve safety awareness among the radiation staff, and, more important, the hospital leaders as well. (author)

  19. 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.

  20. 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)

  1. 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

  2. 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)

  3. Prostate specific antigen levels during and after external beam radiotherapy for localized carcinoma of the prostate: Predictor of therapeutic efficancy

    International Nuclear Information System (INIS)

    Rodrigus, P.; Landeghem, A.A.J. van

    1992-01-01

    For 105 patients with locoregional carcinoma of the prostate, prostate specific antigen (PSA) levels were evaluated before, during and after external beam radiotherapy. The median follow-up is 17 months. In 51 patients (48.5%) initial PSA levels exceeded the maximum normal value of 20 ng/ml. Nine patients kept non-declining high levels just after radiotherapy. Only one of these is free of disease. Assuming PSA levels decrease exponentially during radiotherapy, a mean half-life of 62 days (median 54, SD 26 days) was calculated. Three out of five patients with a PSA half-life of more than 88 days relapsed as compared to a 8% (3/37) relapse rate in patients with a 'normal' half-life. Prolonged PSA half-life suggests residual disease. PSA levels are expected to further decrease after radiation. Six months after irradiation persistent high PSA levels were found in 14/51 (27.5%) patients. Only four of them had no evidence of manifest disease. Important negative prognostic factors for disease control in our series were non-declining high levels of PSA, a PSA serum half-life exceeding 88 days and persistence of elevated PSA values longer than six months after treatment. In our opinion, PSA is a valuable marker in the follow-up of prostate cancer patients during and after radiotherapy. (orig.) [de

  4. Radiation damage at the molecular level: Nanodosimetry

    International Nuclear Information System (INIS)

    Blanco, F.; Munoz, A.; Lagares, J. I.; Nunez, L.; Garcia, G.

    2013-01-01

    One of the main practical use of the model is its use as a tool of nanodosimetry which basically consists in characterizing the effect of radiation on nano volumes (comparable to the DNA of volumes) in terms of link breaks and molecular dissociations. (Author)

  5. 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

  6. 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

  7. 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

  8. Natural radiation level and doses to population in Anhui province

    International Nuclear Information System (INIS)

    1985-01-01

    The absorbed dose rates in air 1 m above the ground from natural radiation and terrestrial gamma radiation in Anhui Province were surveyed. One measurement was made in every area of 90 km 2 . The absorbed dose rates in air from terrestrial radiation range from 54 to 90 nGy.h -1 with an average of 70 nGy.h -1 . The ratios of indoors-to-outdoors and of roads-to-outdoors are 1.5 and 0.9 respectively. The annual effective dose equivalent from external radiation is 0.68-1.05 mSv. The population-weighted average values for mountain area, plain, hilly land, and the Changjiang River basin as well as the annual collective effective dose equivalent were calculated

  9. Evidence for beneficial low level radiation effects and radiation hormesis

    International Nuclear Information System (INIS)

    Feinendegen, L.E.

    2005-01-01

    Low doses in the mGy range cause a dual effect on cellular DNA. One effect concerns a relatively low probability of DNA damage per energy deposition event and it increases proportional with dose, with possible bystander effects operating. This damage at background radiation exposure is orders of magnitudes lower than that from endogenous sources, such as ROS. The other effect at comparable doses brings an easily obeservable adaptive protection against DNA damage from any, mainly endogenous sources, depending on cell type, species, and metabolism. Protective responses express adaptive responses to metabolic perturbations and also mimic oxygen stress responses. Adaptive protection operates in terms of DNA damage prevention and repair, and of immune stimulation. It develops with a delay of hours, may last for days to months, and increasingly disappears at doses beyond about 100 to 200 mGy. Radiation-induced apoptosis and terminal cell differentiation occurs also at higher doses and adds to protection by reducing genomic instability and the number of mutated cells in tissues. At low doses, damage reduction by adaptive protection against damage from endogenous sources predictably outweighs radiogenic damage induction. The analysis of the consequences of the particular low-dose scenario shows that the linear-no-threshold (LNT) hypothesis for cancer risk is scientifically unfounded and appears to be invalid in favor of a threshold or hormesis. This is consistent with data both from animal studies and human epidemiological observations on low-dose induced cancer. The LNT hypothesis should be abandoned and be replaced by a hypothesis that is scientifically justified. The appropriate model should include terms for both linear and non-linear response probabilities. Maintaining the LNT-hypothesis as basis for radiation protection causes unressonable fear and expenses. (author)

  10. Responses to the low-level-radiation controversy

    International Nuclear Information System (INIS)

    Bond, V.P.

    1981-01-01

    Some data sets dealing with the hazards of low-level radiation are discussed. It is concluded that none of these reports, individually or collectively, changes appreciably or even significantly the evaluations of possible low-level radiation effects that have been made by several authoritative national and international groups

  11. Physiological benefits from low levels of ionizing radiation

    International Nuclear Information System (INIS)

    Luckey, T.D.

    1982-01-01

    Extensive literature indicates that minute doses of ionizing radiation benefit animal growth and development, fecundity, health and longevity. Specific improvements appear in neurologic function, growth rate and survival of young, wound healing, immune competence, and resistance to infection, radiation morbidity, and tumor induction and growth. Decreased mortality from these debilitating factors results in increased average life span following exposure to minute doses of ionizing radiation. The above phenomena suggest the possibility that ionizing radiation may be essential for life. Limited data with protozoa suggest that reproduction rates decrease when they are maintained in subambient radiation environments. This may be interpreted to be a radiation deficiency. Evidence must now be obtained to determine whether or not ionizing radiation is essential for growth, development, nutrient utilization, fecundity, health and longevity of higher animals. Whether or not ionizing radiation is found to be essential for these physiologic functions, the evidence reviewed indicates that the optimal amount of this ubiquitous agent is imperceptibly above ambient levels. (author)

  12. Cosmic radiation doses at flight level altitudes of airliners

    International Nuclear Information System (INIS)

    Viragh, E.; Petr, I.

    1985-01-01

    Changes are discussed in flux density of cosmic radiation particles with time as are the origin of cosmic radiation, the level of cosmic radiation near the Earth's surface, and the determination of cosmic radiation doses in airliners. Doses and dose rates are given measured on different flight routes. In spite of the fact that the flight duration at an altitude of about 10 km makes for about 80% of the total flight time, the overall radiation burden of the crews at 1000 flight hours a year is roughly double that of the rest of the population. (J.C.)

  13. Operational quantities for use in external radiation protection measurements. An investigation of concepts and principles

    International Nuclear Information System (INIS)

    1983-01-01

    Under the terms of the Euratom Treaty the Commission of the European Communities is required to draw up basic standards for the health protection of the general public and workers against the dangers arising from ionizing radiation. The basic standards lay down reference values for particular quantities; these values are required to be measured, and appropriate steps taken to ensure that they are not exceeded. To ensure that the basic standards are applied uniformly in the Member States, it is necessary to harmonize not only national laws but also measurement and recording techniques. As a practical contribution towards this objective, the Commission has since 1964 been conducting intercomparison programmes on operational radiation protection dosimetry. Effective monitoring against the dangers of ionizing radiation cannot be guaranteed unless the measuring instruments meet the necessary requirements, the quantities measured are those for which limit values have been laid down, and the instruments can be calibrated unequivocally. The differences between the concepts of quantity and unit of measurement in radiation protection were often unclear. In the light of developments at international level, the introduction of the international system of units of measurements (SI units) and the contents of ICRP Publication No 26, the services of the European Community responsible for radiation protection decided to review the whole question of quantities. The introduction of the 'index' quantities (absorbed dose index and dose equivalent index) was greeted with initial enthusiasm, but it soon became clear, on closer critical examination, that these too had major shortcomings. The Commission, in collaboration with experts from the Member States of the European Community, has therefore set out in this publication the various considerations and points of view concerning the use of these quantities in practical dosimetry. It is hoped that this publication will be of use to all

  14. Ambient radiation levels in a microPET/CT research laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Sarmento, D.M.; Rodrigues, D.L.; Sanches, M.P.; Carneiro, J.C.G.G., E-mail: janetegc@ipen.br [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    This study focuses on initial radiological evaluation and the exposure situation related to the worker task in a micro-positron emission tomography/computed tomography laboratory (microPET/CT). Selected and calibrated thermoluminescent dosimeters, TLD, of CaSO{sub 4}:Dy were used to measure room radiation levels. The detectors were placed in several selected points inside the microPET/CT laboratory and adjacent rooms. In addition, the occupationally exposed workers were monthly evaluated for external and internal exposures. In none of the selected points the dose values exceeded the radiation dose limit established for supervised area, as well as the values obtained in individual monitoring. (author)

  15. Ambient radiation levels in a microPET/CT research laboratory

    International Nuclear Information System (INIS)

    Sarmento, D.M.; Rodrigues, D.L.; Sanches, M.P.; Carneiro, J.C.G.G.

    2015-01-01

    This study focuses on initial radiological evaluation and the exposure situation related to the worker task in a micro-positron emission tomography/computed tomography laboratory (microPET/CT). Selected and calibrated thermoluminescent dosimeters, TLD, of CaSO 4 :Dy were used to measure room radiation levels. The detectors were placed in several selected points inside the microPET/CT laboratory and adjacent rooms. In addition, the occupationally exposed workers were monthly evaluated for external and internal exposures. In none of the selected points the dose values exceeded the radiation dose limit established for supervised area, as well as the values obtained in individual monitoring. (author)

  16. Measurements of individual doses from external radiation in the Brjansk region of the Russian republic of the USSR

    International Nuclear Information System (INIS)

    Wallstroem, E.; Woehni, T.

    1991-01-01

    Individual doses from external photon radiation to various occupational groups in three different villages in the Brjansk region of the Russian republic of the USSR have been measured by individual TL-dosemeters. A total of 86 persons were monitored for a period of 10 days in September 1990, from which 83 dosemeters were returned. The villages had different levels of deposition, but they all belonged to the ''strictly controlled zone'', i.e. deposition levels 555 to 1480 kBq/m 2 (15 to 40 Ci/km 2 ). The results show individual effective dose equivalents during one month in the range 80 to 1000 μSv. Schoolchildren received the lowest doses, and different groups of fields workers the highest. Estimated mean annual effective dose equivalents ranged from 2.0 mSv to 4.6 mSv for the different occupational groups and types of dwellings. Monthly mean effective dose equivalents relative to the reported mean deposition of Cs-137 ranged from 110 (in-door workers in stone houses) to 290 μSv per MBq/m 2 (out-door workers in wooden houses). The reported results are lower than theorectical estimates based on the reported level on contamination. The ratio of the mean effective dose equivalent for persons living in wooden and stone houses ranged from 1.4 to 2.6 for the various villages and occupational groups. 21 refs., 5 figs., 9 tabs

  17. Health effects of low level radiation

    International Nuclear Information System (INIS)

    Chevillard, S.; Ugolin, N.; Lebeau, J.; Ory, K.

    2006-01-01

    Nuclear energy production is necessarily associated with the handling and storage of radioactive elements, which are liable to have deleterious effects on human health, and on environment. These deleterious effects are varied, but they greatly depend on the dose, which has been received, and the exposure type. Therefore, only intense and massive exposures are liable to be clinically detected. They can entail immediate consequences, even lead to the person's death. Thanks to safety measures, which have been implemented to an international scale, this occurs very rarely. Excluding extensive accidental cases, medical irradiation for therapeutic use and conflicts, workers and population in general are exposed to low doses and low dose-rates. Low dose exposures, resulting from either a contamination or an external irradiation are more frequent. In fact, we could say that the whole humanity is concerned by natural exposure, which varies depending on regions, as well as by medical exposure, which varies depending on the medicalisation status of the country. (author)

  18. 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

  19. 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.

  20. Examining the Dynamic Structure of Daily Internalizing and Externalizing Behavior at Multiple Levels of Analysis

    Directory of Open Access Journals (Sweden)

    Aidan G.C. Wright

    2015-12-01

    Full Text Available Psychiatric diagnostic covariation suggests that the underlying structure of psychopathology is not one of circumscribed disorders. Quantitative modeling of individual differences in diagnostic patterns has uncovered several broad domains of mental disorder liability, of which the Internalizing and Externalizing spectra have garnered the greatest support. These dimensions have generally been estimated from lifetime or past-year comorbidity patters, which are distal from the covariation of symptoms and maladaptive behavior that ebb and flow in daily life. In this study, structural models are applied to daily diary data (Median = 94 days of maladaptive behaviors collected from a sample (N = 101 of individuals diagnosed with personality disorders. Using multilevel and unified structural equation modeling, between-person, within-person, and person-specific structures were estimated from 16 behaviors that are encompassed by the Internalizing and Externalizing spectra. At the between-person level (i.e., individual differences in average endorsement across days we found support for a two-factor Internalizing-Externalizing model, which exhibits significant associations with corresponding diagnostic spectra. At the within-person level (i.e., dynamic covariation among daily behavior pooled across individuals we found support for a more differentiated, four-factor, Negative Affect-Detachment-Hostility-Impulsivity structure. Finally, we demonstrate that the person-specific structures of associations between these four domains are highly idiosyncratic.

  1. Examining the Dynamic Structure of Daily Internalizing and Externalizing Behavior at Multiple Levels of Analysis

    Science.gov (United States)

    Wright, Aidan G. C.; Beltz, Adriene M.; Gates, Kathleen M.; Molenaar, Peter C. M.; Simms, Leonard J.

    2015-01-01

    Psychiatric diagnostic covariation suggests that the underlying structure of psychopathology is not one of circumscribed disorders. Quantitative modeling of individual differences in diagnostic patterns has uncovered several broad domains of mental disorder liability, of which the Internalizing and Externalizing spectra have garnered the greatest support. These dimensions have generally been estimated from lifetime or past-year comorbidity patters, which are distal from the covariation of symptoms and maladaptive behavior that ebb and flow in daily life. In this study, structural models are applied to daily diary data (Median = 94 days) of maladaptive behaviors collected from a sample (N = 101) of individuals diagnosed with personality disorders (PDs). Using multilevel and unified structural equation modeling, between-person, within-person, and person-specific structures were estimated from 16 behaviors that are encompassed by the Internalizing and Externalizing spectra. At the between-person level (i.e., individual differences in average endorsement across days) we found support for a two-factor Internalizing–Externalizing model, which exhibits significant associations with corresponding diagnostic spectra. At the within-person level (i.e., dynamic covariation among daily behavior pooled across individuals) we found support for a more differentiated, four-factor, Negative Affect-Detachment-Hostility-Disinhibition structure. Finally, we demonstrate that the person-specific structures of associations between these four domains are highly idiosyncratic. PMID:26732546

  2. Health effects of low-level radiations

    International Nuclear Information System (INIS)

    Tubiana, M.

    1982-01-01

    Epidemiological surveys have attempted to assess the carcinogenic risk induced by exposure to low doses of ionizing radiation. Such studies are difficult to carry out because the incidence of radiation induced cancers is of only a few per cent, even following relativity large doses, and because there is no way to distinguish radiation induced cancer from the background of natural human cancers; moreover these surveys are exposed to many biases due to relatively small sizes of the populations studied and the difficulties of finding an appropriate control group, of estimating the absorbed doses and of collecting the data. A few national or international expert committees have analysed the available data and evaluated the carcinogenic effects. Their estimations of the risk, are similar and allow one to quantify the carcinogenic risk for doses above 100 rads. The risks of lower doses must be determined by extrapolation from human data at high doses. This extrapolation requires the knowledge of the dose-effect relationship. A linear extrapolation is most common and probably leads to a conservative estimate of the risk. A linear-quadratic function is probably more realistic and in better accordance with most scientific data. However the validity of its use for the estimation of carcinogenic risk is still debated. In experimental animals, the influence of dose-rate is important and some data suggest that this is the same for the carcinogenic effect in human beings. The genetic effects are probably less important than was feared a few years ago. The most important recent observation is the absence of any significant genetic effect in the progeny of the survivors of the A. bombs in Hiroshima and Nagasaki. This allows a conservative estimate of the maximum genetic risk for human beings [fr

  3. The effect of interaural-level-difference fluctuations on the externalization of sound

    DEFF Research Database (Denmark)

    Catic, Jasmina; Santurette, Sébastien; Buchholz, Jörg M.

    2013-01-01

    Real-world sound sources are usually perceived as externalized and thus properly localized in both direction and distance. This is largely due to (1) the acoustic filtering by the head, torso, and pinna, resulting in modifications of the signal spectrum and thereby a frequency-dependent shaping...... of interaural cues and (2) interaural cues provided by the reverberation inside an enclosed space. This study first investigated the effect of room reverberation on the spectro-temporal behavior of interaural level differences (ILDs) by analyzing dummy-head recordings of speech played at different distances...... in a standard listening room. Next, the effect of ILD fluctuations on the degree of externalization was investigated in a psychoacoustic experiment performed in the same listening room. Individual binaural impulse responses were used to simulate a distant sound source delivered via headphones. The ILDs were...

  4. Intermediate bands versus levels in non-radiative recombination

    International Nuclear Information System (INIS)

    Luque, Antonio; Marti, Antonio; Antolin, Elisa; Tablero, Cesar

    2006-01-01

    There is a practical interest in developing semiconductors with levels situated within their band gap while preventing the non-radiative recombination that these levels promote. In this paper, the physical causes of this non-radiative recombination are analyzed and the increase in the density of the impurities responsible for the mid-gap levels to the point of forming bands is suggested as the means of suppressing the recombination. Simple models supporting this recommendation and helping in its quantification are presented

  5. 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

  6. 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)

  7. 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

  8. 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.

  9. 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.

  10. Health effects of low-level radiation in shipyard workers

    International Nuclear Information System (INIS)

    Matanoski, G.M.

    1991-06-01

    The Nuclear Shipyard Workers Study (NSWS) was designed to determine whether there is an excess risk of leukemia or other cancers associated with exposure to low levels of gamma radiation. The study compares the mortality experience of shipyard workers who qualified to work in radiation areas to the mortality of similar workers who hold the same types of jobs but who are not authorized to work in radiation areas. The population consists of workers from six government and two private shipyards

  11. Experience of water chemistry and radiation levels in Swedish BWRs

    International Nuclear Information System (INIS)

    Ivars, R.; Elkert, J.

    1981-01-01

    From the BWR operational experience in Sweden it has been found that the occupational radiation exposures have been comparatively low in an international comparison. One main reason for the favourable conditions is the good water chemistry performance. This paper deals at first with the design considerations of water chemistry and materials selection. Next, the experience of water chemistry and radiation levels are provided. Finally, some methods to further reduce the radiation sources are discussed. (author)

  12. 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)

  13. An overview of radiation protection at national level in Greece

    International Nuclear Information System (INIS)

    Dimitriou, P.A.

    1997-01-01

    The Greek radiation protection Regulations were revised extensively and harmonized with the relevant Euratom Directives in 1991, covering almost all applications of ionizing radiation. According to the low in force, Greek Atomic Energy Commission (GAEC) is the regulatory and competent authority on radiation protection matters. Among others is responsible: for evaluating the environmental radiation, for introducing emergency plans to responsible Ministries to cope with radiation accidents or increased radioactivity levels, for issuing safety regulation concerning the operation employing ionizing radiation, performing inceptions to all installations or laboratories where radioisotopes or radiation producing machines are employed including all medical applications and issuing the certificate of compliance with the radiation protection regulations. GAEC is the governmental licensing authority for import, export, possession, use, transport and disposal of radioactive materials including fissile materials, and is also responsible for providing training and education to scientists and technical personnel on radiation protection and operates a two years postgraduate course in Medical radiation Physics in collaboration with three Greek Universities, leading to an M Sc degree.The achievements, initiatives and perceptivities of GAEC in the fields of its responsibility are discussed. Statistical data concerning the application of ionising radiation in Greece during the last five years are also presented (author)

  14. 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)

  15. 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

  16. Environmental levels of microwave radiation around a satellite earth station

    International Nuclear Information System (INIS)

    Joyner, K.H.; Bangay, M.J.

    1986-01-01

    This paper discusses the background to claims of possible adverse health effects arising from exposure to environmental levels of microwave radiation around satellite earth stations. Results of a recent survey of the environmental levels of microwave radiation around two 32 metre diameter satellite communications antennas owned and operated by the Overseas Telecommunications Commission (OTC) of Australia are presented. From the measurements obtained in this survey it can be concluded that the environmental levels of microwave radiation around the OTC and similar satellite facilities do not pose a health risk to persons in the vicinity

  17. Radiation levels on empty cylinders containing heel material

    Energy Technology Data Exchange (ETDEWEB)

    Shockley, C.W. [Martin Marietta Energy Systems, Inc., Paducah, KY (United States)

    1991-12-31

    Empty UF{sub 6} cylinders containing heel material were found to emit radiation levels in excess of 200 mr/hr, the maximum amount stated in ORO-651. The radiation levels were as high as 335 mr/hr for thick wall (48X and 48Y) cylinders and 1050 mr/hr for thin wall (48G and 48H) cylinders. The high readings were found only on the bottom of the cylinders. These radiation levels exceeded the maximum levels established in DOT 49 CFR, Part 173.441 for shipment of cylinders. Holding periods of four weeks for thick-wall cylinders and ten weeks for thin-wall cylinders were established to allow the radiation levels to decay prior to shipment.

  18. 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

  19. 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

  20. 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.

  1. 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

  2. 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.)

  3. 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%.

  4. Genetic effects of low level radiation

    International Nuclear Information System (INIS)

    Sumner, D.

    1988-01-01

    The author outlines the evidence for genetic effects. The incidence of congenital abnormalities, stillbirths and child deaths has been examined in 70,000 pregnancies in Hiroshima and Nagasaki and compared with pregnancies in an unirradiated control group. No difference was detected in incidence of congenital abnormalities of stillbirths, but there was a small insignificant increase in child deaths when both parents were exposed. The number of children born with chromosome aberrations was slightly higher, but insignificant in the exposed group compared with controls. However, surveys of congenital malformations in children of radiologists and in children of Hanford workers suggest a genetic effect of radiation. Absolute and relative methods of calculating risks and the ICRP risk factor is also briefly discussed. (U.K.)

  5. Radiation levels in the SSC interaction regions

    Energy Technology Data Exchange (ETDEWEB)

    Groom, D.E. [ed.

    1988-06-10

    The radiation environment in a typical SSC detector has been evaluated using the best available particle production models coupled with Monte Carlo simulations of hadronic and electromagnetic cascades. The problems studied include direct charged particle dose, dose inside a calorimeter from the cascades produced by incident photons and hadrons, the flux of neutrons and photons backscattered from the calorimeter into a central cavity, and neutron flux in the calorimeter. The luminosity lifetime at the SSC is dominated by collision losses in the interaction regions, where the luminosity is equivalent to losing an entire full-energy proton beam into the apparatus every six days. The result of an average p-p collision can be described quite simply. The mean charged multiplicity is about 110, and the particles are distributed nearly uniformly in pseudorapidity ({eta}) over all the angles of interest. The transverse momentum distribution is independent of angle, and for our purposes may be written as p{perpendicular}exp(-p{perpendicular}/{beta}). The mean value of p{perpendicular} may be as high as 0.6 GeV/c. Most of the radiation is produced by the very abundant low-p{perpendicular} particles. The dose or neutron fluence produced by individual particles in this energy region are simulated over a wide variety of conditions, and several measurements serve to confirm the simulation results. In general, the response (a dose, fluence, the number of backscattered neutrons, etc.) for an incident particle of momentum p can be parameterized in the form Np{sup {alpha}}, where 0.5 < {alpha}< 1.0. The authors believe most of their results to be accurate to within a factor of two or three, sufficiently precise to serve as the basis for detailed designs.

  6. High level radiation dosimetry in biomedical research

    International Nuclear Information System (INIS)

    Inada, Tetsuo

    1979-01-01

    The physical and biological dosimetries relating to cancer therapy with radiation were taken up at the first place in the late intercomparison on high LET radiation therapy in Japan-US cancer research cooperative study. The biological dosimetry, the large dose in biomedical research, the high dose rate in biomedical research and the practical dosimeters for pulsed neutrons or protons are outlined with the main development history and the characteristics which were obtained in the relating experiments. The clinical neutron facilities in the US and Japan involved in the intercomparison are presented. Concerning the experimental results of dosimeters, the relation between the R.B.E. compared with Chiba (Cyclotron in National Institute of Radiological Sciences) and the energy of deuterons or protons used for neutron production, the survival curves of three cultured cell lines derived from human cancers, after the irradiation of 250 keV X-ray, cyclotron neutrons of about 13 MeV and Van de Graaff neutrons of about 2 MeV, the hatchability of dry Artemia eggs at the several depths in an absorber stack irradiated by 60 MeV proton beam of 40, 120 and 200 krad, the peak skin reaction of mouse legs observed at various sets of average and instantaneous dose rates, and the peak skin reaction versus three instantaneous dose rates at fixed average dose rate of 7,300 rad/min are shown. These actual data were evaluated numerically and in relation to the physical meaning from the viewpoint of the fundamental aspect of cancer therapy, comparing the Japanese measured values to the US data. The discussion record on the high dose rate effect of low LET particles on biological substances and others is added. (Nakai, Y.)

  7. Effects of low levels of radiation on humans

    International Nuclear Information System (INIS)

    Auxier, J.A.

    1981-01-01

    The state of knowledge on effects of low-level ionizing radiations on humans is reviewed. Several problems relating to dose thresholds or lack of thresholds for several types of cancer and high LET radiations and the effects of fractionation and dose protection are discussed

  8. Level of Radiofrequency (RF) Radiations from GSM Base Stations ...

    African Journals Online (AJOL)

    Levels of radiofrequency radiations around two global systems for mobile communication (GSM) base stations located in the vicinity of a residential quarter and workplace complex were measured. The effects of the radiofrequency radiations on albino mice placed in exposure cages and located around the base stations ...

  9. Radiation levels from computer monitor screens within Benue State ...

    African Journals Online (AJOL)

    Investigation of possible presence of soft X-ray levels from Computer Screens at distances of 0.5m and 1.0m was carried out within Benue State University, Makurdi, using ten different monitor models. Radiation measurement was carried out using a portable digital radiation meter, INSPECTOR 06250 (SE international Inc.

  10. 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

  11. 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

  12. A geographically resolved method to estimate levelized power plant costs with environmental externalities

    International Nuclear Information System (INIS)

    Rhodes, Joshua D.; King, Carey; Gulen, Gürcan; Olmstead, Sheila M.; Dyer, James S.; Hebner, Robert E.; Beach, Fred C.; Edgar, Thomas F.; Webber, Michael E.

    2017-01-01

    In this analysis we developed and applied a geographically-resolved method to calculate the Levelized Cost of Electricity (LCOE) of new power plants on a county-by-county basis while including estimates of some environmental externalities. We calculated the LCOE for each county of the contiguous United States for 12 power plant technologies. The minimum LCOE option for each county varies based on local conditions, capital and fuel costs, environmental externalities, and resource availability. We considered ten scenarios that vary input assumptions. We present the results in a map format to facilitate comparisons by fuel, technology, and location. For our reference analysis, which includes a cost of $62/tCO_2 for CO_2 emissions natural gas combined cycle, wind, and nuclear are most often the lowest-LCOE option. While the average cost increases when internalizing the environmental externalities (carbon and air pollutants) is small for some technologies, the local cost differences are as high as $0.62/kWh for coal (under our reference analysis). These results display format, and online tools could serve as an educational tool for stakeholders when considering which technologies might or might not be a good fit for a given locality subject to system integration considerations. - Highlights: • We propose a method to add externalities to LCOE. • We present the least cost technology for every county in the US. • The cheapest technology depends on many characteristics of that locale. • We present online tools for users to change our assumptions. • Our tools are useful in discussing the impact of policy on the cost of electricity.

  13. Development of the national register of radiation workers: subsystem for individual monitoring of external exposure

    International Nuclear Information System (INIS)

    Yu Haitao; Niu Haowei; Sun Quanfu; Fu Yinghua; Fan Yaohua; Yue Baorong

    2010-01-01

    Objective: To develop a national registry and reporting system of individual monitoring for workers occupationally exposed to ionizing radiation. Methods: In accordance with the relevant law, regulations, standards and the current health supervision practice for radiation workers in China, to ensure more effective collection of information on individual monitoring from all levels of service providers across the country and an easy query and analysis of the collected information for both service providers and administrative institutions, the register consisted of an offline-system and a web-based information system. The off-line system consisted of 8 tables, which could easily make annual and period monitoring reports, and upload individual monitoring data in compressed and encrypted format. Web-based system consisted of 6 modules, could easily make S customized tabulations of monitoring data and show 2 trend figures. SSLVPN secure remote access was used in the system. Arranged by the Ministry of Health, training courses provided to all individual monitoring service providers and provincial administrative institutions. Results: A new and individual-based national register and reporting system of individual monitoring for workers occupationally exposed to ionizing radiation was successfully developed, and would be officially run soon. Conclusions: The establishment and running of the register would be great improvement on the national radiological health reports and produce a far-reaching impact on the individual monitoring in China. (authors)

  14. Quality assurance in personal dosimetry of external radiation: present situation and future needs

    International Nuclear Information System (INIS)

    Ma, N.

    2006-01-01

    Whole body personal dosimetry is well established for the individual monitoring of radiation workers. High quality radiation dosimetry is essential for workers who rely upon personal dosemeters to record the amount of radiation to which they are exposed. The mandate has been given to the Personal Dosimetry, (secondary standard dosimetry laboratories) S.S.D.L., (Malaysian institute for nuclear energy research) M.I.N.T. to assure the individual monitoring for radiation workers in Malaysia. In 2005, the S.S.D.L;-M.I.N.T. supply, process and read out of personal dosemeters of nearly 13,000 dosimeters monthly, whereby. 12,000 are films and 1,000 are T.L.D.s. The objective of individual monitoring is not limited to the measurement of doses delivered to individuals, but it should demonstrate that limits of exposure have not been exceeded and that working conditions have not unexpectedly deteriorated. Dosimetry measurements are an important component of radiation protection programs and must be of high quality. The exposure of workers to radiation must be controlled and monitored in order to comply with regulatory requirements. S.S.D.L.-M.I.N.T; demonstrates that its performance is at an acceptable level by implementing overall system performance, as evidenced by the ISO 9001 certification of the Personal Dosimetry Service in 2002 and ISO/I.E.C. 17025 accreditation to the calibration laboratory in 2004. The certification and accreditation processes achieved the goal by formalizing the recognition of satisfactory performance, and providing evidence of this performance. Overall performances are assessed, personnel operating the system will be trained and are well qualified and all actions will be documented. The paper describes the overview of the Q.M.S. carried out at the S.S. D.L.-M.I.N.T.. During the implementation of Q.M.S. a few areas has been identified for future consideration. These include performance specification and type testing of dosemeters, which provide a

  15. Aspects of two-level systems under external time-dependent fields

    Energy Technology Data Exchange (ETDEWEB)

    Bagrov, V.G.; Wreszinski, W.F. [Tomsk State University and Tomsk Institute of High Current Electronics (Russian Federation); Barata, J.C.A.; Gitman D.M. [Universidade de Sao Paulo, Instituto de Fisica (Brazil)]. E-mails: jbarata@fma.if.usp.br; gitman@fma.if.usp.br

    2001-12-14

    The dynamics of two-level systems in time-dependent backgrounds is under consideration. We present some new exact solutions in special backgrounds decaying in time. On the other hand, following ideas of Feynman et al, we discuss in detail the possibility of reducing the quantum dynamics to a classical Hamiltonian system. This, in particular, opens the possibility of directly applying powerful methods of classical mechanics (e.g. KAM methods) to study the quantum system. Following such an approach, we draw conclusions of relevance for 'quantum chaos' when the external background is periodic or quasi-periodic in time. (author)

  16. 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

  17. Examining a link between SPEs and ground level radiation

    Science.gov (United States)

    Overholt, Andrew

    2015-01-01

    Researchers have previously found a correlation between solar proton events (SPEs) and congenital malformations (CMs). A similar correlation has also been found between long term solar variability and CMs. We examine the ionizing radiation dose from these events as well as the largest events on record to determine whether these events are capable of producing these effects. We show that the total ionizing radiation dose (consisting of neutrons and muons) at ground level is insufficient for production of the observed increases in CM rate under the current paradigm regarding ionizing radiation from muons and neutrons. Current research on the subject shows that our assumptions regarding muonic ionizing radiation may be underestimating their biologic effect. We recommend further experimentation regarding the radiation dose due to muons, as this may prove to be a more substantial contribution to our radiation environment than previously assumed.

  18. Measurement of Background Gamma Radiation Levels at Two ...

    African Journals Online (AJOL)

    MICHAEL

    ABSTRACT: An in-situ measurement of the background radiation level was carried out at the vicinity of three ... Soil contains small quantities of radioactive elements along with their progeny. .... assessment for soil samples from Kestanbol.

  19. Effects of high vs low-level radiation exposure

    International Nuclear Information System (INIS)

    Bond, V.P.

    1983-01-01

    In order to appreciate adequately the various possible effects of radiation, particularly from high-level vs low-level radiation exposure (HLRE, vs LLRE), it is necessary to understand the substantial differences between (a) exposure as used in exposure-incidence curves, which are always initially linear and without threshold, and (b) dose as used in dose-response curves, which always have a threshold, above which the function is curvilinear with increasing slope. The differences are discussed first in terms of generally familiar nonradiation situations involving dose vs exposure, and then specifically in terms of exposure to radiation, vs a dose of radiation. Examples are given of relevant biomedical findings illustrating that, while dose can be used with HLRE, it is inappropriate and misleading the LLRE where exposure is the conceptually correct measure of the amount of radiation involved

  20. Risks of low-level radiation - the evidence of epidemiology

    International Nuclear Information System (INIS)

    Gloag, D.

    1980-01-01

    The difficulties involved in estimating risks from very low levels of radiation and the use of dose-response models for cancer incidence are discussed with reference to the third BEIR Committee report on the Effects on Populations of Exposure to low levels of Ionizing Radiation (1980). Cancer risk estimates derived from different epidemiological studies are reviewed. They include atom bomb survivors, medically irradiated groups and occupational groups. (36 references). (author)

  1. 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

  2. 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)

  3. 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

  4. 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

  5. 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

  6. 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

  7. Labor migration, externalities and ethics: theorizing the meso-level determinants of HIV vulnerability.

    Science.gov (United States)

    Hirsch, Jennifer S

    2014-01-01

    This paper discusses labor migration as an example of how focusing on the meso-level highlights the social processes through which structural factors produce HIV risk. Situating that argument in relation to existing work on economic organization and HIV risk as well as research on labor migration and HIV vulnerabilities, the paper demonstrates how analyzing the processes through which labor migration creates vulnerability can shift attention away from the proximate behavioral determinants of HIV risk and toward the community and policy levels. Further, it presents the concepts of externalities and the ethics of consumption, which underline how both producers and consumers benefit from low-waged migrant labor, and thus are responsible for the externalization of HIV risk characteristic of supply chains that rely on migrant labor. These concepts point to strategies through which researchers and advocates could press the public and private sectors to improve the conditions in which migrants live and work, with implications for HIV as well as other health outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Evaluation of radiation protection educational level of professional exposed workers

    International Nuclear Information System (INIS)

    Marinkovic, O.; Krstev, S.; Jovanovic, S.

    2006-01-01

    Full text: Serbia and Montenegro legislation concerning with radiation protection was upgrading after publication ICRP- 60 and B.S.S., No.115. Present Law on the Protection against Ionizing Radiation is in force from 1996. Among quite new issues in radiation protection regulations there was article relate to obligatory refresher training. Due to adverse political and economic situation through many years radiation protection regulations were not fulfill completely. The aim of this investigation was to get real view to education level of professional exposed workers. In Serbia and Montenegro the most of ionizing radiation sources are in medical use and the most exposed workers are radiographers and radiologists. The test was passed by 200 radiographers and 50 radiologists. Main groups of questions were: Radiation protection and safety; difference between safety and security; legislation: law and regulations; incidents, accidents and operational failures: recording, learning. Usually, knowledge from school pales. New quantities (as ambient and personal dose equivalent) are mostly unknown. It is easier to understand the real difference between safety and security than to understand linguistic differences. Discussing regulations workers are more interesting in syndicate regulations than radiation protection ones. Operational failures and incidents are hidden. Better to say: nobody dare to speak about them. The results imposed conclusion that regulatory body has to pay more attention to upraise safety culture and radiation protection education level of professional exposed workers. (authors)

  9. Low-level radiation effects: a fact book

    International Nuclear Information System (INIS)

    Brill, A.B.; Adelstein, S.J.; Saenger, E.L.; Webster, E.W.

    1982-01-01

    Low Level Raidation Effects: A Fact Book, prepared by the Society of Nuclear Medicine Subcommittee on the Risks of Low-Level Ionizing Radiation, attempts to examine the health effects of small doses of radiation. For immediate questions, this work provides a well-organized brief summary of recent radiologic data from refereed scientific literature and from the publications of advisory groups such as the National Council of Radiation Protection and Measurement (NCRP), the International Commission on Radiological Protection (ICRP), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and the National Academy of Sciences (NAS). Since it consists almost entirely of tables and graphs from the above-mentioned sources along with summary paragraphs, the Fact Book is very useful in the preparation of lectures. The book is divided into seven sections. Chapter One, Glossary, Units and Conversion Factors, is useful because nearly all data given in the rest of the book is in conventional units and should be converted to SI units for future technical audiences. Chapter 2, Radiobiology, covers the fundamental principles of the field. Chapter 3, Radiation Doses, can be used to help an audience appreciate the relative magnitudes of radiation exposures they may read about or encounter. Chapter 4, Late Somatic Effects of Low Doses of Ionizing Radiation, gives data concerning cancer induction and embryonic effects, and Chapter 5 provides data on genetic effects Chapter 6, Risks, Statistical Facts and Public Perception can be used to compare the risks of radiation exposure with more commonly encountered risks

  10. Regulatory control of low level radiation exposure in Tanzania

    International Nuclear Information System (INIS)

    Nyanda, A.M.; Muhogora, W.E.

    1997-01-01

    In Tanzania, the radiation protection law was issued in 1983. Under this law, the National Radiation Commission is responsible for safe uses of ionizing radiation. The regulatory control of the resulting doses from the uses of radiation sources in medicine, industry, research and teaching is presented. The system of control reflects the existing interactions between the National Radiation Commission and users through the established radiation protection infrastructure. From the national dose registry data, it is found that the highest annual individual doses over 10 years ago, came from less than 5% of total monitored workers and were in the range 10 - 15 mSv y -1 . The experienced radiation levels in uncontrolled areas of potential workplaces is less than 1 μSv h -1 . The possibility for associating such low dose levels to the effectiveness of the existing regulatory dose control framework is discussed. Despite of this achievement, the need to improve further the radiation protection and safety programs is found necessary. (author)

  11. 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)

  12. 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.

  13. 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)

  14. 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.

  15. The Radiation Levels for Household Goods Made in Korea

    International Nuclear Information System (INIS)

    Kim, Hee Reyoung; Park, Doo Won; Lee, Wan No; Choi, Sang Do; Chung, Kun Ho; Kang, Mun Ja; Choi, Geun Sik; Lee, Chang Woo

    2008-01-01

    The environmental radiation based on a natural and artificial radiation always exists in the environment. The natural radiation includes cosmic ray coming into the atmosphere from outer space, radiation emitted from the earth's crust or soil, radiation by the radon in the air and its progenies. These natural radiation comes from various buildings like a house and an apartment, agricultural and stock breeding products like rice and milk, and a body, etc. The artificial radiation emanates from a nuclear power plant, a radioisotope facility, a radioactive waste disposal site, a medical or research facility treating a radioactive material, a radiation generation device for an industry, TV, a microwave oven, appliances like a fluorescent clock, an airport security table, etc. Among the various kinds of radioactive nuclides that existed in the earth's crust at the time of the earth's formation about 4,000 million years ago, all the short half life nuclides decayed and the long half life nuclides remain amid the nuclides of a half life with more than 100 million years and their progenies now. In fact, the natural radiation level is determined by the nuclides of the Thorium series which have K-40 (half life 1.25 billion years), Th-232 (half life 14.5 billion years) as a parent nuclide, the nuclides of the uranium series which have U-238 (half life 4.5 billon years) as a parent nuclide, and the cosmic ray like photon and muon. These nuclides are distributed in the soil, sea water, construction material and body with different concentrations. Different radiation dose rates are presented in different regions due to the different concentrations of the radioactive minerals included at the materials. Actually, Brazil and India reveal a relatively high natural radiation level

  16. 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%).

  17. 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)

  18. 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

  19. 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.

  20. Quantifying the spatial and temporal variation in dose from external exposure to radiation: a new tool for use on free-ranging wildlife

    International Nuclear Information System (INIS)

    Hinton, Thomas G.; Byrne, Michael E.; Webster, Sarah; Beasley, James C.

    2015-01-01

    Inadequate dosimetry is often the fundamental problem in much of the controversial research dealing with radiation effects on free-ranging wildlife. Such research is difficult because of the need to measure dose from several potential pathways of exposure (i.e., internal contamination, external irradiation, and inhalation). Difficulties in quantifying external exposures can contribute significantly to the uncertainties of dose-effect relationships. Quantifying an animal's external exposure due to spatial–temporal use of habitats that can vary by orders of magnitude in radiation levels is particularly challenging. Historically, wildlife dosimetry studies have largely ignored or been unable to accurately quantify variability in external dose because of technological limitations. The difficulties of quantifying the temporal–spatial aspects of external irradiation prompted us to develop a new dosimetry instrument for field research. We merged two existing technologies [Global Positioning Systems (GPS) and electronic dosimeters] to accommodate the restrictive conditions of having a combined unit small enough to be unobtrusively worn on the neck of a free-ranging animal, and sufficiently robust to withstand harsh environmental conditions. The GPS–dosimeter quantifies the spatial and temporal variation in external dose as wildlife traverse radioactively contaminated habitats and sends, via satellites, an animal's location and short term integrated dose to the researcher at a user-defined interval. Herein we describe: (1) the GPS–dosimeters; (2) tests to compare their uniformity of response to external irradiation under laboratory conditions; (3) field tests of their durability when worn on wildlife under natural conditions; and (4) a field application of the new technology at a radioactively contaminated site. Use of coupled GPS–dosimetry will allow, for the first time, researchers to better understand the relationship of animals to their contaminated

  1. System-Level Model for OFDM WiMAX Transceiver in Radiation Environment

    International Nuclear Information System (INIS)

    Abdel Alim, O.; Elboghdadly, N.; Ashour, M.M.; Elaskary, A.M.

    2008-01-01

    WiMAX (Worldwide Inter operability for Microwave Access), an evolving standard for point-to-multipoint wireless networking, works for the l ast mile c onnections for replacing optical fiber technology network but with no need for adding more infra structure within crowded areas. Optical fiber technology is seriously considered for communication and monitoring applications in space and around nuclear reactors. Space and nuclear environments are characterized, in particular, by the presence of ionizing radiation fields. Therefore the influence of radiation on such networks needs to be investigated. This paper has the objective of building a System level model for a WiMAX OFDM (Orthogonal Frequency Division Multiplexing) based transceiver. Modeling irradiation noise as an external effect added to the Additive White Gaussian noise (AWGN). Then analyze, discuss the results based on qualitatively performance evaluation using BER calculations for radiation environment

  2. The Utility of PET/CT in the Planning of External Radiation Therapy for Prostate Cancer.

    Science.gov (United States)

    Calais, Jeremie; Cao, Minsong; Nickols, Nicholas G

    2018-04-01

    Radiotherapy and radical prostatectomy are the definitive treatment options for patients with localized prostate cancer. A rising level of prostate-specific antigen after radical prostatectomy indicates prostate cancer recurrence, and these patients may still be cured with salvage radiotherapy. To maximize chance for cure, the irradiated volumes should completely encompass the extent of disease. Therefore, accurate estimation of the location of disease is critical for radiotherapy planning in both the definitive and the salvage settings. Current first-line imaging for prostate cancer has limited sensitivity for detection of disease both at initial staging and at biochemical recurrence. Integration of PET into routine evaluation of prostate cancer patients may improve both staging accuracy and radiotherapy planning. 18 F-FDG PET/CT is now routinely used in radiation planning for several cancer types. However, 18 F-FDG PET/CT has low sensitivity for prostate cancer. Additional PET probes evaluated in prostate cancer include 18 F-sodium fluoride, 11 C-acetate, 11 C- or 18 F-choline, 18 F-fluciclovine, and 68 Ga- or 18 F-labeled ligands that bind prostate-specific membrane antigen (PSMA). PSMA ligands appear to be the most sensitive and specific but have not yet received Food and Drug Administration New Drug Application approval for use in the United States. Retrospective and prospective investigations suggest a potential major impact of PET/CT on prostate radiation treatment planning. Prospective trials randomizing patients to routine radiotherapy planning versus PET/CT-aided planning may show meaningful clinical outcomes. Prospective clinical trials evaluating the addition of 18 F-fluciclovine PET/CT for planning of salvage radiotherapy with clinical endpoints are under way. Prospective trials evaluating the clinical impact of PSMA PET/CT on prostate radiation planning are indicated. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

  3. 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

  4. 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

  5. Multiple organizational identification levels and the impact of perceived external prestige and communication climate

    NARCIS (Netherlands)

    Bartels, J.; Pruyn, A.T.H.; Jong, de M.D.T.; Joustra, I.

    2007-01-01

    Earlier studies have shown that perceived external prestige and communication climate influence organizational identification. In this paper we present the results of a study of the influence of communication climate and perceived external prestige on organizational identification at various

  6. Low-level radioactive waste disposal: radiation protection laws

    International Nuclear Information System (INIS)

    Chapuis, A.M.; Guetat, P.; Garbay, H.

    1991-01-01

    The politics of radioactive waste management is a part of waste management and activity levels are one of the components of potential waste pollutions in order to assume man and environment safety. French regulations about personnel and public' radiation protection defines clearly the conditions of radioactive waste processing, storage, transport and disposal. But below some activity levels definite by radiation protection laws, any administrative procedures or processes can be applied for lack of legal regulations. So regulations context is not actually ready to allow a rational low-level radioactive waste management. 15 refs.; 4 tabs.; 3 figs

  7. Environmental policy. Ambient radioactivity levels and radiation doses in 1998

    International Nuclear Information System (INIS)

    1999-11-01

    The report contains information on the natural (background) radiation exposure (chapter II), the natural radiation exposure as influenced by anthropogenic effects (chapter III), the anthropogenic radiation exposure (chapter IV), and the radiation doses to the environment and the population emanating from the Chernobyl fallout (chapter V). The natural radiation exposure is specified referring to the contributions from cosmic and terrestrial background radiation and intake of natural radioactive substances. Changes of the natural environment resulting from anthropogenic effects (technology applications) inducing an increase in concentration of natural radioactive substances accordingly increase the anthropogenic radiation exposure. Indoor air radon concentration in buildings for instance is one typical example of anthropogenic increase of concentration of natural radioactivity, primarily caused by the mining industry or by various materials processing activities, which may cause an increase in the average radiation dose to the population. Measurements so far show that indoor air concentration of radon exceeds a level of 200 Bq/m 3 in less than 2% of the residential buildings; the EUropean Commission therefore recommends to use this concentration value as a maximum value for new residential buildings. Higher concentrations are primarily measured in areas with relevant geological conditions and abundance of radon, or eg. in mining areas. (orig./CB) [de

  8. Tolerance doses of cutaneous and mucosal tissues in ring-necked parakeets (Psittacula krameri) for external beam megavoltage radiation.

    Science.gov (United States)

    Barron, Heather W; Roberts, Royce E; Latimer, Kenneth S; Hernandez-Divers, Stephen; Northrup, Nicole C

    2009-03-01

    Currently used dosages for external-beam megavoltage radiation therapy in birds have been extrapolated from mammalian patients and often appear to provide inadequate doses of radiation for effective tumor control. To determine the tolerance doses of cutaneous and mucosal tissues of normal birds in order to provide more effective radiation treatment for tumors that have been shown to be radiation responsive in other species, ingluvial mucosa and the skin over the ingluvies of 9 ring-necked parakeets (Psittacula krameri) were irradiated in 4-Gy fractions to a total dose of either 48, 60, or 72 Gy using an isocentric cobalt-60 teletherapy unit. Minimal radiation-induced epidermal changes were present in the high-dose group histologically. Neither dose-related acute nor chronic radiation effects could be detected in any group grossly in cutaneous or mucosal tissue over a 9-month period. Radiation doses of 72 Gy in 4-Gy fractions were well tolerated in the small number of ring-necked parakeets in this initial tolerance dose study.

  9. Analysis of radiation level on dinosaur fossil in Zigong

    International Nuclear Information System (INIS)

    Yang Changshu; Liang Shuzhi; Fan Zhengnian.

    1995-01-01

    Study on radiation level of dinosaur fossil and environment in conservation zone in Zigong, Sichuan has been done. The results showed that the γ radiation dose and radioactivity strength of 232 Th and 40 K in dinosaur fossil, soil and rock in the conservation zone were within the limits of radioactive background value in Zigong. Radioactivity strength of 238 U, 226 Ra in dinosaur fossil were 26.6 and 29.2 times higher than the rock of same layer respectively

  10. Reduction of the pool-top radiation level in HANARO

    International Nuclear Information System (INIS)

    Lee, Choong-Sung; Park, Sang-Jun; Kim, Heonil; Park, Yong-Chul; Choi, Young-San

    1999-01-01

    HANARO is an open-tank-in-pool type reactor. Pool water is the only shielding to minimize the pool top radiation level. During the power ascension test of HANARO, the measured pool top radiation level was higher than the design value because some of the activation products in the coolant reached the pool surface. In order to suppress this rising coolant, the hot water layer system (HWL) was designed and installed to maintain l.2 meter-deep hot water layer whose temperature is 5degC higher than that of the underneath pool surface. After the installation of the HWL system, however, the radiation level of the pool-top did not satisfy the design value. The operation modes of the hot water layer system and the other systems in the reactor pool, which had an effect on the formation of the hot water layer, were changed to reduce pool-top radiation level. After the above efforts, the temperature and the radioactivity distribution in the pool was measured to confirm whether this system blocked the rising coolant. The radiation level at the pool-top was significantly reduced below one tenth of that before installing the HWL and satisfied the design value. It was also confirmed by calculation that this hot water layer system would significantly reduce the release of fission gases to the reactor hall and the environment during the hypothetical accident as well. (author)

  11. Acceptable level of radiation risk and its perception

    Energy Technology Data Exchange (ETDEWEB)

    Kusama, Tomoko; Shinozaki, Motoshi; Yoshizawa, Yasuo

    1987-03-01

    The acceptable level of radiation risk for public members, that is 10/sup -5//y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10/sup -5//y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10/sup -5//y as acceptable risk level in Japan. The perception to risk level of 10/sup -5//y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one.

  12. Acceptable level of radiation risk and its perception

    International Nuclear Information System (INIS)

    Kusama, Tomoko; Shinozaki, Motoshi; Yoshizawa, Yasuo

    1987-01-01

    The acceptable level of radiation risk for public members, that is 10 -5 /y, was proposed by ICRP and other international organizations. We studied to survey basic procedures of deriving this value and to derive an acceptable risk value in Japan by using similar procedures. The basic procedures to derive 10 -5 /y were found as follows; (1) 0.1 percent of annual mortality from all diseases, (2) 0.1 percent of life time risk, (3) one percent of mortality from all causes in each age cohort and (4) corresponding value to 1 mSv annual radiation exposure. From these bases we derived the value of 10 -5 /y as acceptable risk level in Japan. The perception to risk level of 10 -5 /y in conventional life was investigated by means of questionnaires for 1,095 college students living in Tokyo. The risks considered in this study were natural background radiation, coffee, skiing, X-ray diagnosis, spontaneous cancer, passive smoking and air pollution. The most acceptable risk was the risk related with natural background radiation. And the risk of natural background radiation was more easily accepted by the students who had knowledges on natural background radiation. On the other hand, the risk from air pollution or passive smoking was the most adverse one. (author)

  13. Evaluating natural radiation level by existing airborne radioactive data

    International Nuclear Information System (INIS)

    Mingkao, Hu; Changqing, Han; Jiangqi, Fang; Zhengxin, Shen

    2002-01-01

    Airborne Survey and Remote Sensing Center of Nuclear Industry, founded in the middle of 1950s, is a unique unit specialized in uranium exploration by airborne radioactive survey in China. Large numbers of airborne data of radioactivity and abundant experience have been accumulated for more than 40 years. All-round detailed investigation of environmental radiation levels in our country will not be completed in the near future. Thus, at present it is considered to evaluate natural radiation levels using the existing radioactive data. This paper introduces the results of analysis and study comparing airborne radioactive data for radiation environmental evaluation obtained from survey area in Gansu, China, in the 2001 with the measurement results by ground gamma ray radiation dose-rate instrument for environment. The air-earth inter-comparison error does not exceed 30% at radiation fields with a definite area, and the air-earth inter-comparison error does not exceed 60% at outcrop of granite. In 6km long profile that has various circumstances, such as desert, Gobi, farmland and residential area, minimum of air absorbed dose rate is 47nGy/h at an altitude of 1 meter above the soil plane, maximum is 68nGy/h. The inter-comparison errors are usually less than 20%, and maximum is 25.38%. This shows that it is feasible to obtain natural radiation levels rapidly if we could use the existing radioactive data adequately and make some correction, such as geology factor

  14. A retrospective analysis of 140 dogs with oral melanoma treated with external beam radiation.

    Science.gov (United States)

    Proulx, David R; Ruslander, David M; Dodge, Richard K; Hauck, Marlene L; Williams, Laurel E; Horn, Birgitte; Price, G Sylvester; Thrall, Donald E

    2003-01-01

    Despite the early notion that canine oral malignant melanoma is radioresistant, recent data suggest that external beam radiotherapy is effective in local tumor control. However, optimal fractionation schedules have not been established. The high rate of regional and distant metastasis is another problem that has hindered long-term control. The role of chemotherapy in the management of canine oral melanoma has also not been determined. In this study, data from 140 dogs irradiated at North Carolina State University were evaluated with the following objectives: (1) to compare the efficacy of three radiation therapy protocols (36 Gy, 9 Gy x 4 fractions; 30 Gy, 10 Gy x 3 fractions; or >45 Gy, 2-4 Gy x 12-19 fractions) for the treatment of dogs with oral malignant melanoma, (2) to identify any host or tumor factors influencing prognosis, and (3) to determine the impact of systemic chemotherapy on treatment outcome. Information regarding response to therapy, disease progression, and survival were determined from the medical records or from information obtained by telephone or mail survey. Relationships between host, tumor, and treatment variables and outcome measures (response, time to first event, and survival) were evaluated using Fisher's exact test (response) and the Cox regression model (time to first event and survival). The median time to first event for the 140 dogs was 5.0 months (95% C.I., 4-6 months) and the median survival was 7.0 months (95% C.I., 6-9 months). In the univariate analysis, the following variables were associated with increased time to first event and survival: (1) rostral tumor sublocation; (2) lack of bone lysis observed on skull imaging, and (3) microscopic tumor burden. In a multivariate analysis of 111 dogs with complete data for these variables, tumor sublocation, bone lysis, and tumor volume were identified as joint predictors of time to first event (p oral malignant melanoma; however, the optimal fractionation scheme has yet to be

  15. Human thyroid cancer induction by ionizing radiation: summary of studies based on external irradiation and radioactive iodines

    International Nuclear Information System (INIS)

    Shore, R.E.

    1996-01-01

    To provide a context for the Chernobyl thyroid cancer experience, a summary of the findings from other studies is given. The data on external radiation and thyroid cancer come primarily from studies of children irradiated for a variety of benign medical conditions and the Japanese atomic bomb cohort. Unfortunately, only small amounts of data are currently available on thyroid cancer following radioactive iodine exposure in childhood. In order to predict the risk of thyroid cancer in the Chernobyl experience, a number of radiation-related factors need to be considered: the magnitude of radiation risk from available studies; shape of the dose-response curve; variations in risk by gender, time since irradiation, and age at irradiation; the effects of dose fractionation or dose protraction. Other considerations pertaining to the frequency of thyroid cancer and its outcome are thyroid-tumor surveillance effects and background iodine intake. The data to date suggest that 131 I produces less thyroid cancer than a comparable dose of external radiation, but the Chernobyl experience will provide extensive new information on this issue. Principles are discussed as to how to maximize the scientific validity and informativeness of Chernobyl thyroid studies

  16. Normal tissue tolerance to external beam radiation therapy: Thyroid; Dose de tolerance des tissus sains: la thyroide

    Energy Technology Data Exchange (ETDEWEB)

    Berges, O.; Giraud, P. [Service d' oncologie-radiotherapie, hopital europeen Georges-Pompidou, universite Paris Descartes, 75 - Paris (France); Belkacemi, Y. [Service d' oncologie-radiotherapie, CHU Henri-Mondor, universite Paris 12, 94 - Creteil (France)

    2010-07-15

    The thyroid is the most developed endocrine gland of the body. Due to its anatomical location, it may be exposed to ionizing radiation in external radiotherapy involving head and neck. This review aims to describe the thyroid radiation disorders, probably under-reported in the literature, their risk factors and follow-up procedures. The functional changes after external beam radiation consists mainly of late effects occurring beyond 6 months, and are represented by the clinical and subclinical hypothyroidism. Its incidence is approximately 20 to 30% and it can occur after more than 25 years after radiation exposure. Hyperthyroidism and auto-immune manifestations have been described in a lesser proportion. The morphological changes consist of benign lesions, primarily adenomas, and malignant lesions, the most feared and which incidence is 0.35%. The onset of hypothyroidism depends of the total dose delivered to the gland, and the irradiated. Modern techniques of conformal radiotherapy with modulated intensity could improve the preservation of the thyroid, at the expense of the increase in low doses and the theoretical risk of secondary cancers. (authors)

  17. Guidelines on the medical therapy of persons accidentally overexposed to ionizing radiations. External contamination

    International Nuclear Information System (INIS)

    Perez, M.R.; Di Trano, J.L.; Gisone, P.

    1998-01-01

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

  18. Does exposure to very high levels of natural radiation induce hematological alterations in humans?

    International Nuclear Information System (INIS)

    Ghiassi-Nejad, M.

    2003-01-01

    Full text: It has long been known that total body exposure to moderate doses decrease the number of circulating erythrocytes, platelets, granulocytes, and lymphocytes. However, data on hematopoietic effects of exposure to very low doses of ionizing radiation in humans are scarce. Recently it has been reported that hematological parameters have significant positive associations with the radiation dose received by residents lived near a nuclear power plant. Ramsar, a city in northern Iran, has some inhabited areas with the highest levels of natural radiation studied so far. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy y -1 and the highest recorded external gamma dose rates are about 130 mGy y -1 . In this study, hematological parameters such as counts of leukocytes, lymphocytes, monocytes, granulocytes, red blood cells, hemoglobin, hematocrit, MCV, MCH, MCHC, RDW, PLT, and MPV were measured in the inhabitants. The results of this study indicated that there was no any statistically significant alteration in hematological parameters of the inhabitants of very high background radiation areas of Ramsar compared to those of a neighboring control area

  19. [Level of microwave radiation from mobile phone base stations built in residential districts].

    Science.gov (United States)

    Hu, Ji; Lu, Yiyang; Zhang, Huacheng; Xie, Hebing; Yang, Xinwen

    2009-11-01

    To investigate the condition of microwave radiation pollution from mobile phone base station built in populated area. Random selected 18 residential districts where had base station and 10 residential districts where had no base stations. A TES-92 electromagnetic radiation monitor were used to measure the intensity of microwave radiation in external and internal living environment. The intensities of microwave radiation in the exposure residential districts were more higher than those of the control residential districts (p station, it would gradually weaken with the increase of the distance. The level of microwave radiation in antenna main lobe region is not certainly more higher than the side lobe direction, and the side lobe direction also is not more lower. At the same district, where there were two base stations, the electromagnetic field nestification would take place in someplace. The intensities of microwave radiation outside the exposure windows in the resident room not only changed with distance but also with the height of the floor. The intensities of microwave radiation inside the aluminum alloys security net were more lower than those of outside the aluminum alloys security net (p 0.05). Although all the measure dates on the ground around the base station could be below the primary standard in "environment electromagnetic wave hygienic standard" (GB9175-88), there were still a minorities of windows which exposed to the base station were higher, and the outside or inside of a few window was even higher beyond the primary safe level defined standard. The aluminum alloys security net can partly shield the microwave radiation from the mobile phone base station.

  20. Evaluation of magnetic fluid hyperthermia (MFH) combined with external radiation in an orthotopic rat model of prostate cancer

    International Nuclear Information System (INIS)

    Johannsen, M.; Thiesen, B.; Taymoorian, K.; Gneveckow, U.; Waldoefner, N.; Koch, M.; Scholz, R.; Lein, M.; Jung, K.; Loening, S.A.; Jordan, A.

    2005-01-01

    Full text: Magnetic fluid hyperthermia (MFH) is a new concept of cancer treatment based on AC magnetic field-induced excitation of biocompatible superparamagnetic nanoparticles. Preliminary studies of MFH using nanoscaled aminosilan-coated magnetites have demonstrated the feasibility of minimally invasive MFH in the Dunning tumor model. Here we evaluated the effect of two sequential MFH treatments, combined with external radiation, in an orthotopic Dunning R3327-MatLyLu prostate cancer model. MFH led to a significant growth inhibition in this orthotopic model of the aggressive MatLyLu tumor variant. Furthermore, combined MFH and radiation with 20 Gy equally effective in inhibiting tumor growth as radiation with 60 Gy, suggesting a significant synergistic effect. Intratumoral deposition of magnetic fluids was found to be stable, allowing for serial MFH treatments without repeated injection. The optimal treatment schedules of this combination regarding temperatures, sequencing and fractionation need to be defined in further experimental studies. (author)

  1. Morfologic anomalies in the spermatozoid heads caused by isolated and combined effects of external ionizing radiation and chemical factor

    International Nuclear Information System (INIS)

    Shopova, V.; Nechev, Khr.; Sylovski, P.

    1985-01-01

    The test for recording morphologic anomalies in the spermatozoid heads and the genotoxic effect of isolated and combined treatment with the preparation chloracetophone and external ionizing radiation was applied on of mice line C 57 Bl. Evaluation of the morphologic anomalies in the spermatozoa rested upon two staining method, one of which helped to distinguish the acrosome. It was demonstrated that chloracetophone given in a single high dose (1/2 and 1/4 LD 50 ) was genotoxic. Ionizing radiation induced the expected positive effect. After combined application of 5x1/5 LD 50 chloracetophone and 1 and 4 Gy irradiation dose, it was the effect of radiation that was recorded. Only in the group in which both noxious agents were combined in effective doses (1/2 LD 50 chloracetophone and 1 Gy) there was a tendency toward additive effect

  2. Assessment of health-cost externalities of air pollution at the national level using the EVA model system

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, J.; Silver, J.D.; Frohn, L.M. (and others)

    2011-07-15

    Air pollution has significant negative impacts on human health and well-being, which entail substantial economic consequences. We have developed an integrated model system, EVA (External Valuation of Air pollution; Frohn et al., 2005; Andersen et al., 2007; Brandt et al., 2010), to assess health-related economic externalities of air pollution resulting from specific emission sources or sectors. The EVA system was initially developed to assess externalities from power production, but in this study it is extended to evaluate costs at the national level from all major emission sectors. In this study, we estimate the impacts and total externality costs from the main emission sectors in Denmark, representing the 10 major SNAP codes. Furthermore, we assess the impacts and externality costs of all emissions simultaneously from the whole of Europe as well as from international ship traffic in general, since this sector seems to be very important but is currently unregulated. (Author)

  3. Measurement uncertainty in broadband radiofrequency radiation level measurements

    Directory of Open Access Journals (Sweden)

    Vulević Branislav D.

    2014-01-01

    Full Text Available For the evaluation of measurement uncertainty in the measurement of broadband radio frequency radiation, in this paper we propose a new approach based on the experience of the authors of the paper with measurements of radiofrequency electric field levels conducted in residential areas of Belgrade and over 35 municipalities in Serbia. The main objective of the paper is to present practical solutions in the evaluation of broadband measurement uncertainty for the in-situ RF radiation levels. [Projekat Ministarstva nauke Republike Srbije, br. III43009

  4. Case-control study of congenital malformations and occupational exposure to low-level ionizing radiation

    International Nuclear Information System (INIS)

    Sever, L.E.; Gilbert, E.S.; Hessol, N.A.; McIntyre, J.M.

    1988-01-01

    In a case-control study, the authors investigated the association of parental occupational exposure to low-level external whole-body penetrating ionizing radiation and risk of congenital malformations in their offspring. Cases and controls were ascertained from births in two counties in southeastern Washington State, where the Hanford Site has been a major employer. A unique feature of this study was the linking of quantitative individual measurement of external whole-body penetrating ionizing radiation exposure of employees at the Hanford Site, using personal dosimeters, and the disease outcome, congenital malformations. The study population included 672 malformation cases and 977 matched controls from births occurring from 1957 through 1980. Twelve specific malformation types were analyzed for evidence of association with employment of the parents at Hanford and with occupational exposure to ionizing radiation. Two defects, congenital dislocation of the hip and tracheoesophageal fistula, showed statistically significant associations with employment of the parents at Hanford, but not with parental radiation exposure. Neural tube defects showed a significant association with parental preconception exposure, on the basis of a small number of cases. Eleven other defects, including Down syndrome, for which an association with radiation was considered most likely, showed no evidence of such an association. When all malformations were analyzed as a group, there was no evidence of an association with employment of the parents at Hanford, but the relation of parental exposure to radiation before conception was in the positive direction (one-tailed p value between 0.05 and 0.10). Given the number of statistical tests conducted, some or all of the observed positive correlations are likely to represent false positive findings. 30 references

  5. Early effect of external beam radiation therapy on the anal sphincter: A study using anal manometry and transrectal ultrasound

    International Nuclear Information System (INIS)

    Birnbaum, E.H.; Dreznik, Z.; Myerson, R.J.; Lacey, D.L.; Fry, R.D.; Kodner, I.J.; Fleshman, J.W.

    1992-01-01

    The early of pelvic irradiation on the anal sphincter has not been previously investigated. This study prospectively evaluated the acute effect of preoperative radiation on anal function. Twenty patients with rectal carcinoma received 4,500 cGy of preoperative external beam radiation. The field of radiation included the sphincter in 10 patients and was delivered above the anorectal ring in 10 patients. Anal manometry and transrectal ultrasound were performed before and four weeks after radiotherapy. No significant difference in mean maximal squeeze or resting pressure was found after radiation therapy. An increase in mean minimal sensory threshold was significant. Histologic examination revealed minimal radiation changes at the distal margin in 8 of 10 patients who underwent low anterior resection and in 1 of 3 patients who underwent abdominoperineal resection. The authors conclude that preoperative radiation therapy has minimal immediate effect on the anal sphincter and is not a major contributing factor to postoperative incontinence in patients after sphincter-saving operations for rectal cancer

  6. ASAMPSA-E guidance for level 2 PSA Volume 2. Implementing external Events modelling in Level 2 PSA

    International Nuclear Information System (INIS)

    Cazzoli, E.; Vitazkova, J.; Loeffler, H.; Burgazzi, L.

    2016-01-01

    The objective of the present document is to provide guidance on the implementation of external events into an 'extended' L2 PSA. It has to be noted that L2 PSA addresses issues beginning with fuel degradation and ending with the release of radionuclides into the environment. Therefore, the present document may touch upon, but does not evaluate explicitly issues that involve events or phenomena which occur before the fuel begins to degrade. Following the accident at Fukushima Dai-ichi, the nuclear safety community has realized that much attention should be given to the areas of operator interventions and accidents that may develop at the same time in more than one unit if they are initiated by one or more common external events. For this reason and to fulfill the PSA end-users' wish list (as reflected by an ASAMPSA-E survey), the attention is mostly focused on interface between L1 and L2 PSA, fragility analysis, human response analysis and some consideration is given to L2 PSA modeling of severe accidents for multiple unit sites, even though it is premature to provide extensive guidance in this area. The following recommendations, mentioned in various sections within this document, are summarized here: 1. Vulnerability/fragility analyses should be performed with respect to all external hazards and all structures, systems and components potentially affected that could be relevant to L2 PSA, 2. Importance should be given to the assessment of human performance following extreme external events; for extreme circumstances with high stress level, low confidence is justified for SAM human interventions and for such conditions, human interventions could be analyzed as sensitivity cases only in L2 PSA, 3. Results presentation should include assessment of total risk measures compared with risk targets able to assess all contributions to the risk and to judge properly the safety, 4. Total risk measures shall be associated to appropriate information on all

  7. Radiation hormesis: an outcome of exposure to low level ionizing radiation

    International Nuclear Information System (INIS)

    Kant, Krishan

    2012-01-01

    Ionizing radiation is a benign environmental agent at background levels. Human population is always exposed to ionizing radiation from natural sources. Important sources are cosmic rays which come from outer space and from the surface of the sun, terrestrial radionuclides which occur in the earths crust in various geological formations in soils, rocks, building materials, plants, water, food, air and in the human body itself. With the increasing use of radiation in health facilities, scientific research, industry and agriculture, the study of impact of low-level ionizing radiation on environment and possible health effects on future generations has been a cause of concern in recent years. As regards the effects, it is established fact that high doses of ionizing radiation are harmful to health, there exists, however, a substantial controversy regarding the effects of low doses of ionizing radiation (LLIR). In the present paper, brief review of the available literature, data and reports on stimulation by low-dose irradiation and recent data supporting radiation hormesis. A linear quadratic model has been given illustrating the validity of radiation hormesis, besides the comparison of the dose rates arising from natural and manmade sources to the Indian population. This overview summarizes various reports

  8. 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%

  9. 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

  10. Short-term Androgen-Deprivation Therapy Improves Prostate Cancer-Specific Mortality in Intermediate-Risk Prostate Cancer Patients Undergoing Dose-Escalated External Beam Radiation Therapy

    International Nuclear Information System (INIS)

    Zumsteg, Zachary S.; Spratt, Daniel E.; Pei, Xin; Yamada, Yoshiya; Kalikstein, Abraham; Kuk, Deborah; Zhang, Zhigang; Zelefsky, Michael J.

    2013-01-01

    Purpose: We investigated the benefit of short-term androgen-deprivation therapy (ADT) in patients with intermediate-risk prostate cancer (PC) receiving dose-escalated external beam radiation therapy. Methods and Materials: The present retrospective study comprised 710 intermediate-risk PC patients receiving external beam radiation therapy with doses of ≥81 Gy at a single institution from 1992 to 2005, including 357 patients receiving neoadjuvant and concurrent ADT. Prostate-specific antigen recurrence-free survival (PSA-RFS) and distant metastasis (DM) were compared using the Kaplan-Meier method and Cox proportional hazards models. PC-specific mortality (PCSM) was assessed using competing-risks analysis. Results: The median follow-up was 7.9 years. Despite being more likely to have higher PSA levels, Gleason score 4 + 3 = 7, multiple National Comprehensive Cancer Network intermediate-risk factors, and older age (P≤.001 for all comparisons), patients receiving ADT had improved PSA-RFS (hazard ratio [HR], 0.598; 95% confidence interval [CI], 0.435-0.841; P=.003), DM (HR, 0.424; 95% CI, 0.219-0.819; P=.011), and PCSM (HR, 0.380; 95% CI, 0.157-0.921; P=.032) on univariate analysis. Using multivariate analysis, ADT was an even stronger predictor of improved PSA-RFS (adjusted HR [AHR], 0.516; 95% CI, 0.360-0.739; P<.001), DM (AHR, 0.347; 95% CI, 0.176-0.685; P=.002), and PCSM (AHR, 0.297; 95% CI, 0.128-0.685; P=.004). Gleason score 4 + 3 = 7 and ≥50% positive biopsy cores were other independent predictors of PCSM. Conclusions: Short-term ADT improves PSA-RFS, DM, and PCSM in patients with intermediate-risk PC undergoing dose-escalated external beam radiation therapy

  11. Prognostic Utility of Cell Cycle Progression Score in Men With Prostate Cancer After Primary External Beam Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Freedland, Stephen J., E-mail: steve.freedland@duke.edu [Department of Surgery, Durham VA Medical Center, Durham, North Carolina (United States); Department of Surgery (Urology), Duke University School of Medicine, Durham, North Carolina (United States); Department of Pathology, Duke University School of Medicine, Durham, North Carolina (United States); Gerber, Leah [Department of Surgery, Durham VA Medical Center, Durham, North Carolina (United States); Department of Surgery (Urology), Duke University School of Medicine, Durham, North Carolina (United States); Department of Pathology, Duke University School of Medicine, Durham, North Carolina (United States); Reid, Julia; Welbourn, William; Tikishvili, Eliso; Park, Jimmy; Younus, Adib; Gutin, Alexander; Sangale, Zaina; Lanchbury, Jerry S. [Myriad Genetics, Inc, Salt Lake City, Utah (United States); Salama, Joseph K. [Department of Radiation Oncology, Durham VA Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University School of Medicine, Durham, North Carolina (United States); Stone, Steven [Myriad Genetics, Inc, Salt Lake City, Utah (United States)

    2013-08-01

    Purpose: To evaluate the prognostic utility of the cell cycle progression (CCP) score, a RNA signature based on the average expression level of 31 CCP genes, for predicting biochemical recurrence (BCR) in men with prostate cancer treated with external beam radiation therapy (EBRT) as their primary curative therapy. Methods and Materials: The CCP score was derived retrospectively from diagnostic biopsy specimens of men diagnosed with prostate cancer from 1991 to 2006 (n=141). All patients were treated with definitive EBRT; approximately half of the cohort was African American. Outcome was time from EBRT to BCR using the Phoenix definition. Median follow-up for patients without BCR was 4.8 years. Association with outcome was evaluated by Cox proportional hazards survival analysis and likelihood ratio tests. Results: Of 141 patients, 19 (13%) had BCR. The median CCP score for patient samples was 0.12. In univariable analysis, CCP score significantly predicted BCR (P=.0017). The hazard ratio for BCR was 2.55 for 1-unit increase in CCP score (equivalent to a doubling of gene expression). In a multivariable analysis that included Gleason score, prostate-specific antigen, percent positive cores, and androgen deprivation therapy, the hazard ratio for CCP changed only marginally and remained significant (P=.034), indicating that CCP provides prognostic information that is not provided by standard clinical parameters. With 10-year censoring, the CCP score was associated with prostate cancer-specific mortality (P=.013). There was no evidence for interaction between CCP and any clinical variable, including ethnicity. Conclusions: Among men treated with EBRT, the CCP score significantly predicted outcome and provided greater prognostic information than was available with clinical parameters. If validated in a larger cohort, CCP score could identify high-risk men undergoing EBRT who may need more aggressive therapy.

  12. Prostate-specific antigen bounce after high-dose rate brachytherapy with external beam radiation therapy for prostate cancer patients

    International Nuclear Information System (INIS)

    Sakamoto, Naotaka; Kakinoki, Hiroaki; Tsutsui, Akio; Yoshikawa, Masahiro; Iguchi, Atsushi; Matsunobu, Toru; Uehara, Satoru

    2008-01-01

    Prostate-specific antigen (PSA) bounce after high-dose rate (HDR) brachytherapy with external beam radiation therapy (EBRT) for prostate cancer patients was evaluated. Sixty-one patients treated with HDR-brachytherapy followed by EBRT had a minimum follow-up of 12 months (median, 24 months) in our institute. A PSA bounce was defined as a rise of at least 0.1 ng/ml greater than a previous PSA level, with a subsequent decline equal to, or less than, the initial nadir. A PSA bounce was noted in 16 (26.2%) of 61 patients (one patient had a PSA bounce twice). Median time to develop a PSA bounce was 18 months, but 23.5% developed a PSA bounce after 24 months. Median duration of PSA bounce was 6 months and 11.8% had increased PSA within a period of 12 months. Median bounce height was 0.2 ng/ml (range, 0.1 to 3.39 ng/ml). A bounce height of gerater than 2 ng/ml was seen in 11.8%. Clinical characteristics (age, prostate volume, neoadjuvant endocrine therapy, risk classification, stage, pretreatment PSA, Gleason score) do not predict whether or not there will be a PSA bounce. In patients treated with HDR-brachytherapy followed by EBRT, the incidence and characteristics of PSA bounce were similar to those in patients treated with low-dose rate brachytherapy. Physicians should be aware of the possibility of PSA bounce following HDR-brachytherapy with EBRT. (author)

  13. Prognostic Utility of Cell Cycle Progression Score in Men With Prostate Cancer After Primary External Beam Radiation Therapy

    International Nuclear Information System (INIS)

    Freedland, Stephen J.; Gerber, Leah; Reid, Julia; Welbourn, William; Tikishvili, Eliso; Park, Jimmy; Younus, Adib; Gutin, Alexander; Sangale, Zaina; Lanchbury, Jerry S.; Salama, Joseph K.; Stone, Steven

    2013-01-01

    Purpose: To evaluate the prognostic utility of the cell cycle progression (CCP) score, a RNA signature based on the average expression level of 31 CCP genes, for predicting biochemical recurrence (BCR) in men with prostate cancer treated with external beam radiation therapy (EBRT) as their primary curative therapy. Methods and Materials: The CCP score was derived retrospectively from diagnostic biopsy specimens of men diagnosed with prostate cancer from 1991 to 2006 (n=141). All patients were treated with definitive EBRT; approximately half of the cohort was African American. Outcome was time from EBRT to BCR using the Phoenix definition. Median follow-up for patients without BCR was 4.8 years. Association with outcome was evaluated by Cox proportional hazards survival analysis and likelihood ratio tests. Results: Of 141 patients, 19 (13%) had BCR. The median CCP score for patient samples was 0.12. In univariable analysis, CCP score significantly predicted BCR (P=.0017). The hazard ratio for BCR was 2.55 for 1-unit increase in CCP score (equivalent to a doubling of gene expression). In a multivariable analysis that included Gleason score, prostate-specific antigen, percent positive cores, and androgen deprivation therapy, the hazard ratio for CCP changed only marginally and remained significant (P=.034), indicating that CCP provides prognostic information that is not provided by standard clinical parameters. With 10-year censoring, the CCP score was associated with prostate cancer-specific mortality (P=.013). There was no evidence for interaction between CCP and any clinical variable, including ethnicity. Conclusions: Among men treated with EBRT, the CCP score significantly predicted outcome and provided greater prognostic information than was available with clinical parameters. If validated in a larger cohort, CCP score could identify high-risk men undergoing EBRT who may need more aggressive therapy

  14. Normal tissue tolerance to external beam radiation therapy: Larynx and pharynx

    International Nuclear Information System (INIS)

    Debelleix, C.; Pointreau, Y.; Calais, G.; Pointreau, Y.; Lafond, C.; Denis, F.; Bourhis, J.H.

    2010-01-01

    For head and neck cancers, the radiation dose usually needed to sterilize a macroscopic tumour is at least 70 Gy in conventional fractionation. In the larynx, this dose level enables optimal tumour control while exposing the patient to a limited risk of severe complications. For oropharynx and nasopharynx tumors, it is sometimes possible to limit the dose received by the larynx according to the extent of the primary lesion. Thus, if the tumour constraints permit, the maximum dose to the larynx must be less than 63 to 66 Gy. To reduce the risk of laryngeal edema, it is recommended if possible to limit the mean non-involved larynx dose to 40 to 45 Gy. In the pharynx, literature's data suggested to minimize the volume of the pharyngeal constrictor muscles receiving a dose greater than or equal to 60 Gy. Limiting the volume receiving a dose greater than or equal to 50 Gy reduces the risk of dysphagia. These dose constraints should be tailored to each patient taking into account the extent of the initial primary lesion, the possible addition of chemotherapy or a modified fractionation radiotherapy. (authors)

  15. Dependence of radiation electric conductivity on intensity of external electric field in polymeric dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Sichkar, V P; Tyutnev, A P; Vaisberg, S E [Nauchno-Issledovatel' skij Fiziko-Khimicheskij Inst., Moscow (USSR)

    1975-10-01

    The radiational conductivity (Gsub(p)) at different electric field potentials (E) for a number of low- and high-density polymers was investigated. In a number of cases temperature variations were introduced. Measurements were carried out also under conditions of a single impulse of high-power radiation dose. A relationship was obtained between Gsub(p) and E.

  16. Leaflet manual of external beam radiation therapy for hepatocellular carcinoma: a review of the indications, evidences, and clinical trials

    Directory of Open Access Journals (Sweden)

    Rim CH

    2018-05-01

    Full Text Available Chai Hong Rim, Won Sup Yoon Department of Radiation Oncology, Ansan Hospital, Korea University Medical College, Ansan, Republic of Korea Abstract: The use of external beam radiation therapy (EBRT in the treatment of hepatocellular carcinoma (HCC, which was rarely performed due to liver toxicity with a previous technique, has increased. Palliation of portal vein thrombosis, supplementation for insufficient transarterial chemoembolization, and provision of new curative opportunities using stereotactic body radiotherapy are the potential indications for use of EBRT. The mechanism of EBRT treatment, with its radiobiological and physical perspectives, differs from those of conventional medical treatment or surgery. Therefore, understanding the effects of EBRT may be unfamiliar to physicians other than radiation oncologists, especially in the field of HCC, where EBRT has recently begun to be applied. The first objective of this review was to concisely explain the indications for use of EBRT for HCC for all physicians treating HCC. Therefore, this review focuses on the therapeutic outcomes rather than the detailed biological and physical background. We also reviewed recent clinical trials that may extend the indications for use of EBRT. Finally, we reviewed the current clinical practice guidelines for the treatment of HCC and discuss the current recommendations and future perspectives. Keywords: hepatocellular carcinoma, liver neoplasm, external beam radiotherapy, stereotactic body radiotherapy, clinical trials, sorafenib, guidelines

  17. Abscess of the iliopsoas muscle associated external fistula of the rectum caused by radiation proctitis. A case report

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Shigeru; Imazu, Hiroki; Matubara, Toshiki; Sakurai, Yoichi; Ochiai, Masahiro; Funabiki, Takahiko [Fujita Health Univ., Toyoake, Aichi (Japan). School of Medicine

    1999-12-01

    This paper deals with a case of abscess of the iliopsoas muscle, an intractable external fistula of the rectum caused by radiation proctitis in a 68-year-old man. There were previous histories of undergoing an A-C bypass operation for coronary stricture 10 years before; and undergoing aportial resection of the bladder with radiation therapy for urinary bladder cancer, followed by colostomy for hemorrhage and stricture of the rectum for radiation proctitis 2 years before admission. In April, 1997 when he had been treated at outpatient clinic, exhumation of pusfrom the sacurred that was diagnosed external fistula of the rectum on a fistulography and he was continuously treated on an ambulant basis. On November 17, 1997, the patient had a temperature 38.7deg C, the white blood cell count increased to 35 x 10{sup 4} /ml, inflammation reaction increased, and unconsciousness appeared. An emergency CT revealed retention of fluid in the retroperitoneum covering from the fistulation through the iliopsoas muscle to pelvis. An abscess of the iliopsoas muscle was diagnosed. It was determined that any operations under general anesthesia were impossible due to poor general condition, and an emergency incision drainage was performed under local anesthesia. Thereafter, the patient developed MRSA septicemia which demanded redrainage and strict general management, but he was successfully freed from the management. Although the intractable fistula in persistently present, he was discharged after a resection of sequestrum and is followed on an ambulant basis. (author)

  18. Reciprocal Relationships between Teacher Ratings of Internalizing and Externalizing Behaviors in Adolescents with Different Levels of Cognitive Abilities.

    Science.gov (United States)

    Morin, Alexandre J S; Arens, A Katrin; Maïano, Christophe; Ciarrochi, Joseph; Tracey, Danielle; Parker, Philip D; Craven, Rhonda G

    2017-04-01

    Are internalizing and externalizing behavior problems interrelated via mutually reinforcing relationships (with each behavior leading to increases over time in levels of the other behavior) or mutually suppressing relationships (with each behavior leading to decreases over time in levels of the other behavior)? Past research on the directionality of these relationships has led to ambiguous results, particularly in adolescence. Furthermore, the extent to which prior results will generalize to adolescents with low levels of cognitive abilities remains unknown. This second limit is particularly important, given that these adolescents are known to present higher levels of externalizing and internalizing behaviors than their peers with average-to-high levels of cognitive abilities, and that the mechanisms involved in the reciprocal relationships between these two types of behaviors may differ across both populations. This study examines the directionality of the longitudinal relationships between externalizing and internalizing behavior problems as rated by teachers across three measurement waves (corresponding to Grades 8-10) in matched samples of 138 adolescents (34.78 % girls) with low levels of cognitive abilities and 556 adolescents (44.88 % girls) with average-to-high levels of cognitive abilities. The results showed that the measurement structure was fully equivalent across time periods and groups of adolescents, revealing high levels of developmental stability in both types of problems, and moderately high levels of cross-sectional associations. Levels of both internalizing and externalizing behaviors were higher among adolescents with low levels of cognitive abilities relative to those with average-to-high levels of cognitive abilities. Finally, the predictive analyses revealed negative reciprocal longitudinal relationships (i.e., mutually suppressing relationships) between externalizing and internalizing problems, a result that was replicated within

  19. 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.

  20. Multiple organizational identification levels and the impact of perceived external prestige and communication climate

    NARCIS (Netherlands)

    Bartels, J.; Pruyn, Adriaan T.H.; de Jong, Menno D.T.; Joustra, Inge

    2007-01-01

    sEarlier studies have shown that perceived external prestige and communication climate influence organizational identification. In this paper we present the results of a study of the influence of communication climate and perceived external prestige on organizational identification at various

  1. Biological monitors for low levels of ionising radiation

    International Nuclear Information System (INIS)

    Mohankumar, M.N.; Jeevanram, R.K.

    1995-01-01

    The biological effects of high doses of ionising radiation are well understood and the methods of measurement of these doses well established. However the effects due to extremely low doses remain by and large uncertain. This is because of the fact that at such low doses no gross symptoms are seen. In fact, at these levels the occurrence of double strand breaks leading to the formation of chromosomal aberrations like dicentrics is rare and chances of mutation due to base damage are negligible. Hence neither chromosomal aberration studies nor mutational assays are useful for detecting doses of the order of a few milligray. Results of exhaustive work done by various laboratories indicate that below 20 mGy the chromosomal aberration technique based on scoring of dicentrics cannot distinguish between a linear or a threshold model. However indirect methods like unscheduled DNA synthesis (UDS) and sister chromatid exchanges (SCEs) appear to be promising for the detection of radiation exposures due to low levels of radiation. This report reviews the available literature on the biological effects of low levels of ionising radiation and highlights the merits and demerits of the various methods employed in the measurement of UDS and SCE. The phenomenon of radio-adaptive response (RAR) and its relation to DNA repair is also discussed. (author)

  2. Biological monitors for low levels of ionising radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mohankumar, M N; Jeevanram, R K [Safety Research and Health Physics Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    1996-12-31

    The biological effects of high doses of ionising radiation are well understood and the methods of measurement of these doses well established. However the effects due to extremely low doses remain by and large uncertain. This is because of the fact that at such low doses no gross symptoms are seen. In fact, at these levels the occurrence of double strand breaks leading to the formation of chromosomal aberrations like dicentrics is rare and chances of mutation due to base damage are negligible. Hence neither chromosomal aberration studies nor mutational assays are useful for detecting doses of the order of a few milligray. Results of exhaustive work done by various laboratories indicate that below 20 mGy the chromosomal aberration technique based on scoring of dicentrics cannot distinguish between a linear or a threshold model. However indirect methods like unscheduled DNA synthesis (UDS) and sister chromatid exchanges (SCEs) appear to be promising for the detection of radiation exposures due to low levels of radiation. This report reviews the available literature on the biological effects of low levels of ionising radiation and highlights the merits and demerits of the various methods employed in the measurement of UDS and SCE. The phenomenon of radio-adaptive response (RAR) and its relation to DNA repair is also discussed. (author). 98 refs., 11 figs., 4 tabs.

  3. Evaluation of Differences in Response of DOD Portable Instruments and Solid-State Detectors used by MEXT for Measurement of External Radiations with Attention to the Cosmic Radiation Component

    Science.gov (United States)

    2014-03-01

    Defense Threat Reduction Agency 8725 John J. Kingman Road, MS-6201 Fort Belvoir, VA 22060-6201...Attention to the Cosmic Radiation Component DISTRIBUTION A. Approved for public release: distribution is unlimited March 2014...Portable Instruments and Solid-State Detectors used by MEXT for Measurement of External Radiations with Attention to the Cosmic Radiation Component 5a

  4. Normal tissue tolerance to external beam radiation therapy: Brain and hypophysis

    International Nuclear Information System (INIS)

    Haberer, S.; Assouline, A.; Mazeron, J.J.

    2010-01-01

    Anticancer treatments-induced central nervous system neurotoxicity has become a major problem in recent years. Real advances in therapeutic results for cancer treatments have improved patients survival. Nowadays, central nervous system radiation therapy is widely prescribed, both for palliative and curative treatments in the management of malignant or benign tumors. Recent data on tolerance of normal central nervous system to radiation therapy are reviewed here, early and delayed radiation-induced effects are described and dose recommendations are suggested for clinical practice. (authors)

  5. [Mediator processes in the brain structures in the late periods after external and combined exposure to ionizing radiation].

    Science.gov (United States)

    Taĭts, M Iu; Dudina, T V; Kandybo, T S; Elkina, A I

    1990-01-01

    In experiments with mature Wistar male rats it was shown that X-radiation of 12.9 mCi/kg and the combined effect of X-rays and 131I of 6.5 mCi/kg changed the rate of mediator processes in the structures responsible for the hypothalamic function regulation. At remote times (6 months) following irradiation differences were observed in the discoordination of mediator interrelations associated with the peculiarities of the indirect effect of external and combined irradiation implemented via endocrine mechanism system.

  6. Coupling External Radiation Transport Code Results to the GADRAS Detector Response Function

    International Nuclear Information System (INIS)

    Mitchell, Dean J.; Thoreson, Gregory G.; Horne, Steven M.

    2014-01-01

    Simulating gamma spectra is useful for analyzing special nuclear materials. Gamma spectra are influenced not only by the source and the detector, but also by the external, and potentially complex, scattering environment. The scattering environment can make accurate representations of gamma spectra difficult to obtain. By coupling the Monte Carlo Nuclear Particle (MCNP) code with the Gamma Detector Response and Analysis Software (GADRAS) detector response function, gamma spectrum simulations can be computed with a high degree of fidelity even in the presence of a complex scattering environment. Traditionally, GADRAS represents the external scattering environment with empirically derived scattering parameters. By modeling the external scattering environment in MCNP and using the results as input for the GADRAS detector response function, gamma spectra can be obtained with a high degree of fidelity. This method was verified with experimental data obtained in an environment with a significant amount of scattering material. The experiment used both gamma-emitting sources and moderated and bare neutron-emitting sources. The sources were modeled using GADRAS and MCNP in the presence of the external scattering environment, producing accurate representations of the experimental data.

  7. Radiation transport in high-level waste form

    International Nuclear Information System (INIS)

    Arakali, V.S.; Barnes, S.M.

    1992-01-01

    The waste form selected for vitrifying high-level nuclear waste stored in underground tanks at West Valley, NY is borosilicate glass. The maximum radiation level at the surface of a canister filled with the high-level waste form is prescribed by repository design criteria for handling and disposition of the vitrified waste. This paper presents an evaluation of the radiation transport characteristics for the vitreous waste form expected to be produced at West Valley and the resulting neutron and gamma dose rates. The maximum gamma and neutron dose rates are estimated to be less than 7500 R/h and 10 mRem/h respectively at the surface of a West Valley canister filled with borosilicate waste glass

  8. Assessing risks from occupational exposure to low-level radiation

    International Nuclear Information System (INIS)

    Gilbert, E.S.

    1989-06-01

    Currently, several epidemiological studies of workers who have been exposed occupationally to radiation are being conducted. These include workers in the United States, Great Britain, and Canada, involved in the production of both defense materials and nuclear power. A major reason for conducting these studies is to evaluate possible adverse health effects that may have resulted because of the radiation exposure received. The general subject of health effects resulting from low levels of radiation, including these worker studies, has attracted the attention of various news media, and has been the subject of considerable controversy. These studies provide a good illustration of certain other aspects of the statistician's role; namely, communication and adequate subject matter knowledge. A competent technical job is not sufficient if these other aspects are not fulfilled

  9. Vessel used in radiation counting to determine radioactivity levels

    International Nuclear Information System (INIS)

    Charlton, J.C.; Glover, J.S.; Shephard, B.P.

    1977-01-01

    This invention concerns the vessels used in radiation counting to determine radioactivity levels. These vessels prove to be particularly useful in analyses of the kind where a radioactive element or compound is separated into two phases and the radioactivity of one phase is determined. Such a vessel used in the counting of radiation includes an organic plastic substance tube appreciably cylindrical in shape whose upper end is open whilst the lower end is closed and integral with it, and an anti-radiation shield in metal or in metal reinforced plastic located at the lower end of the tube and extending along the wall of the tube up to a given height. The vessel contains a reaction area of 1 to 10 ml for holding fluid reagents [fr

  10. Estimation of doses to patients with chronic radiation sickness from external occupational exposure

    International Nuclear Information System (INIS)

    Jia Delin; Dai Guangfu

    1991-01-01

    The doses to patients with chronic radiation sickness who had engaged in diagnostic radiology have been estimated according to the radiation work load, type and capacity of X-ray equipment, protection conditions, data of nationwide survey on doses to X-ray workers in China, or the data of dose monitoring in working places. Based on the activities of radium sources, time taken up in performing radium therapy, distance to radium sources and radiation work load, the doses to patients who had engaged in radium therapy have been estimated. The results of estimated average doses for 29 cases of chronic radiation sickness are given. Their average red marrow dose, trunk dose and effective dose equivalent are 1.3 Gy, 1.2 Gy and 1.6 Sv, respectively

  11. Investigation of environmental natural penetrating radiation level in Hubei Province

    International Nuclear Information System (INIS)

    Zhang Sihui; Zhang Jiaxian

    1992-01-01

    The methods and results of the investigation on natural penetrating radiation level in Hubei Province are presented, 290 measuring points of 25 x 25 km-grid were set uniformly up all over the province, with 385 densely measuring points of different types added. The results show that: (1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 60.8, 58.5 and 60.9 nGy ·h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 55.3 nGy·h -1 ; (3) The population-weighted and point-weighed average value of natural γ radiation dose rate inside buildings is 94.5 and 93.2 x 10 nGy·h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 27.8 and 26.3 nGy·h -1 , and outside buildings is 31.8 and 30.4 nGy·h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside building is 121.0 and 120.7 nGy·h -1 , outside buildings is 92.8 and 88.9 nGy·h -1 , respectively; (6) The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.24, 0.52 and 0.76 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 1.2, 2.5 and 3.7 x 10 4 man·Sv, respectively

  12. Investigation of environmental natural penetrating radiation level in Heilongjiang Province

    International Nuclear Information System (INIS)

    Liu Yuncheng; Wu Chengxiang; Zhang Juling; Zhao Defeng

    1994-01-01

    The methods and results of the investigation on natural penetrating radiation level in Heilongjiang Province are presented. 221 25 km x 25 km-grid measuring points were set uniformly up all over the province, with 555 densely measuring points of different types added. The results show that: (1)The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 53.5, 58.5 and 54.2 nGy·h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 58.4 nGy·h -1 ; (3) The population-weighted and point-weighted average value of natural γ radiation dose rate inside buildings is 85.2 and 78.9 nGy·h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 28.6 and 28.1 nGy·h -1 , and outside buildings is 32.4 and 32.2 nGy·h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 109.7 and 112.8 nGy·h -1 , outside buildings is 84.8 and 91.0 nGy·h -1 , respectively; (6) The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.26, 0.48 and 0.73 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 0.8 x 10 4 , 1.6 x 10 4 and 2.4 x 10 4 man·Sv, respectively

  13. Investigation of environmental natural penetrating radiation level in Jiangsu province

    International Nuclear Information System (INIS)

    Liu Ming; Wang Chengbao.

    1993-01-01

    The methods and results of in investigation on natural penetrating radiation level in Jiangsu Province are presented. 182 25 km x 25 km-grid measuring points were set up uniformly all over the province, with 236 densely measuring points of different types added. The results show that: (1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 50.3, 50.6 and 50.4 nGy · h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 47.1 nGy · h -1 ; (3) The population-weighted and point-weighted average value of natural γ radiation dose rate inside buildings is 89.7 and 89.2 nGy · h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 26.0 and 25.8 nGy · h -1 , and outside buildings is 29.2 and 29.1 nGy · h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 115.1 and 115.5 nGy · h -1 , outside buildings is 79.5 and 79.7 nGy · h -1 , respectively; (6) The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.23, 0.48 and 0.71 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 3.0, 1.5 and 4.5 x 10 4 man · Sv, respectively

  14. Investigation of environmental natural penetrating radiation level in Shaanxi Province

    International Nuclear Information System (INIS)

    Zhang Chunfang; Li Jiyin

    1994-01-01

    The methods and results of the investigation on natural penetrating radiation level in Shaanxi Province are presented. 359 25 km x 25 km-grid measuring points were set uniformly up all over the province, with 433 densely measuring points of different types added. The results show that: (1) The area-weighted, population-weighted and point-weighted average value of natural γ radiation dose rate for field is 62.0, 63.0 and 61.0 nGy·h -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 63.0 nGy · h -1 ; (3)The population-weighted and point-weighted average value of natural γ radiation dose rate inside buildings is 100.0 and 98.0 nGy·h -1 , respectively; (4)The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 32.0 and 31.0 nGy·h -1 , and outside buildings is 37.0 and 36.0 nGy·h -1 , respectively; (5)The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 130.0 and 131.0 nGy·h -1 , outside buildings is 130.0 and 130.0 nGy·h -1 , respectively; (6)The annual effective dose equivalent from cosmic ray, natural γ radiation and natural penetrating radiation is 0.55, 0.28 and 0.83 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 1.63, 0.83 and 2.46 x 10 4 man·Sv, respectively

  15. Investigation of environmental natural penetrating radiation level in Anhui province

    International Nuclear Information System (INIS)

    Zhu Jingqiu; Chen Shuping; Jiang Shan; Zhu Xingsheng; Huang Jiangbin; Wu Chuanyong; Wang Weining

    1992-01-01

    The methods and results of the investigation on natural penetrating radiation level in Anhui Province in 1987 are presented. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate for field is 5.67, 5.62 and 5.55 x 10 -8 Gy· -1 , respectively; (2) The point-weighted average value of natural γ radiation dose rate for road is 5.38 x 10 -8 Gy·h -1 ; (3) The point-weighted and population-weighted average value of natural γ radiation dose rate inside buildings is 9.59 and 9.36 x 10 -8 Gy·h -1 , respectively; (4) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 2.64 and 2.62 x 10 -8 ·h -1 , and outside buildings is 2.95 and 2.94 x 10 -8 ·h -1 , respectively; (5) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 12.23 and 11.99 x 10 -8 Gy·h -1 , outside buildings is 8.62 and 8.49 x 10 -8 ·h -1 , respectively; (6) The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.51, 0.24, and 0.75 mSv, respectively; and correspondingly, the annual collective effective dose equivalent is 2.5, 1.2 and 3.7 x 10 4 man·Sv, respectively

  16. Infrastructure of radiation oncology in France: A large survey of evolution of external beam radiotherapy practice

    International Nuclear Information System (INIS)

    Ruggieri-Pignon, Sophie; Pignon, Thierry; Marty, Michel; Rodde-Dunet, Marie-Helene; Destembert, Brigitte; Fritsch, Beatrice

    2005-01-01

    Purpose: To study the structural characteristics of radiation oncology facilities for France and to examine how technological evolutions had to be taken into account in terms of accessibility and costs. This study was initiated by the three health care financing administrations that cover health care costs for the French population. The needs of the population in terms of the geographic distribution of the facilities were also investigated. The endpoint was to make proposals to enable an evolution of the practice of radiotherapy (RT) in France. Methods and materials: A survey designed by a multidisciplinary committee was distributed in all RT facilities to collect data on treatment machines, other equipment, personnel, new patients, and new treatments. Medical advisors ensured site visits in each facility. The data were validated at the regional level and aggregated at the national level for analysis. Results: A total of 357 machines had been installed in 179 facilities: 270 linear accelerators and 87 cobalt units. The distribution of facilities and megavoltage units per million inhabitants over the country was good, although some disparities existed between areas. It appeared that most megavoltage units had not benefited from technological innovation, because 25% of the cobalt units and 57% of the linear accelerators were between 6 and 15 years old. Computed tomography access for treatment preparation was not sufficient, and complete data management systems were scarce (15% of facilities). Seven centers had no treatment planning system. Electronic portal imaging devices were available in 44.7% of RT centers and in vivo dosimetry in 35%. A lack of physicians and medical physicists was observed; consequently, the workload exceeded the normal standard recommended by the French White Book. Discrepancies were found between the number of patients treated per machine per year in each area (range, 244.5-604). Most treatments were delivered in smaller facilities (61

  17. Energy levels and radiative rates for transitions in Ti VI

    International Nuclear Information System (INIS)

    Aggarwal, K M; Keenan, F P; Msezane, A Z

    2013-01-01

    We report on calculations of energy levels, radiative rates, oscillator strengths and line strengths for transitions among the lowest 253 levels of the (1s 2 2s 2 2p 6 ) 3s 2 3p 5 , 3s3p 6 , 3s 2 3p 4 3d, 3s3p 5 3d, 3s 2 3p 3 3d 2 , 3s 2 3p 4 4s, 3s 2 3p 4 4p and 3s 2 3p 4 4d configurations of Ti VI. The general-purpose relativistic atomic structure package and flexible atomic code are adopted for the calculations. Radiative rates, oscillator strengths and line strengths are reported for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2) and magnetic quadrupole (M2) transitions among the 253 levels, although calculations have been performed for a much larger number of levels. Comparisons are made with existing available results and the accuracy of the data is assessed. Additionally, lifetimes for all 253 levels are listed, although comparisons with other theoretical results are limited to only 88 levels. Our energy levels are estimated to be accurate to better than 1% (within 0.03 Ryd), whereas results for other parameters are probably accurate to better than 20%. A reassessment of the energy level data on the National Institute of Standards and Technology website for Ti VI is suggested. (paper)

  18. Low level radiation: how low can you get?

    International Nuclear Information System (INIS)

    Townsley, M.

    1990-01-01

    Information stored on the world's largest data bank concerning the health of nuclear industry workers is to be handed over to researchers at Birmingham University by the US Department of Energy. The data bank contains detailed information on 300,000 nuclear employees, going back to the 1940s. Such a large sample size will allow the results of a previous study conducted on workers in the US nuclear industry to be verified. That study was concluded in 1978 and showed that the risk estimates set by the International Commission on Radiological Protection (ICRP) were between 10 and 30 times too low. The current ICRP estimate allows workers up to 50mSv of exposure to low level radiation per year. Risk estimates have been derived from data relating to the atomic bombings of Hiroshima and Nagasaki. However in those cases the radiation doses were relatively high but over a short period. In the nuclear industry the doses are lower but are long term and this may account for the apparent anomalies such as the incidence of leukaemia amongst children whose fathers have worked in the nuclear industry compared with that for the children whose fathers received radiation doses from the atomic bombings. It is expected the study will show that low-level radiation is more damaging than has previously been thought. (author)

  19. Somatic and genetic effects of low-level radiation

    International Nuclear Information System (INIS)

    Upton, A.C.

    1974-01-01

    Although the biological effects of ionizing radiation are probably better known than those of any other physical or chemical agent in the environment, our information about such effects has come from observations at doses and dose rates which are orders of magnitude higher than natural background environmental radiation levels. Whether, therefore biological effects occur in response to such low levels can be estimated only by extrapolation, based on assumptions about the dose-effect relationship and the mechanisms of the effects in question. Present knowledge suggests the possibility that several types of biological effects may result from low-level irradiation. The induction of heritable genetic changes in germ cells and carcinogenic changes in somatic cells are considered to be the most important from the standpoint of their potential threat to health. On the basis of existing data, it is possible to make only tentative upper limit estimates of the risks of these effects at low doses. The estimates imply that the frequency of such effects attributable to exposure at natural background radiation levels would constitute only a small fraction of their natural incidence. 148 references

  20. Early observed transient prostate-specific antigen elevations on a pilot study of external beam radiation therapy and fractionated MRI guided High Dose Rate brachytherapy boost

    International Nuclear Information System (INIS)

    Singh, Anurag K; Godette, Denise J; Stall, Bronwyn R; Coleman, C Norman; Camphausen, Kevin; Ménard, Cynthia; Guion, Peter; Susil, Robert C; Citrin, Deborah E; Ning, Holly; Miller, Robert W; Ullman, Karen; Smith, Sharon; Crouse, Nancy Sears

    2006-01-01

    To report early observation of transient PSA elevations on this pilot study of external beam radiation therapy and magnetic resonance imaging (MRI) guided high dose rate (HDR) brachytherapy boost. Eleven patients with intermediate-risk and high-risk localized prostate cancer received MRI guided HDR brachytherapy (10.5 Gy each fraction) before and after a course of external beam radiotherapy (46 Gy). Two patients continued on hormones during follow-up and were censored for this analysis. Four patients discontinued hormone therapy after RT. Five patients did not receive hormones. PSA bounce is defined as a rise in PSA values with a subsequent fall below the nadir value or to below 20% of the maximum PSA level. Six previously published definitions of biochemical failure to distinguish true failure from were tested: definition 1, rise >0.2 ng/mL; definition 2, rise >0.4 ng/mL; definition 3, rise >35% of previous value; definition 4, ASTRO defined guidelines, definition 5 nadir + 2 ng/ml, and definition 6, nadir + 3 ng/ml. Median follow-up was 24 months (range 18–36 mo). During follow-up, the incidence of transient PSA elevation was: 55% for definition 1, 44% for definition 2, 55% for definition 3, 33% for definition 4, 11% for definition 5, and 11% for definition 6. We observed a substantial incidence of transient elevations in PSA following combined external beam radiation and HDR brachytherapy for prostate cancer. Such elevations seem to be self-limited and should not trigger initiation of salvage therapies. No definition of failure was completely predictive

  1. Tradescantia in studies of genetic effects of low level radiation

    International Nuclear Information System (INIS)

    Yamashita, Atsushi

    1976-01-01

    Tradescantia in studies on genetic effects of low level radiation is briefly introduced. Radiosensitivity, method of screening stamen hair mutation, materials in current uses, spontaneous mutation rate, and modifying factors are refered. For stamen hair mutation b values in exponential model were lower in irradiation with low dose rate at high environmental temperature. The dose response curves under these modifying conditions, when extrapolated to low dose range, well fit to the line which was obtained by Sparrow's experiment of low level irradiation. In chronic irradiation, the frequency of stamen hair mutation reaches to the constant value after 17 days from the start of irradiation, and is as much as 4 times higher than the peak value in one day irradiation at the same exposure rate. The spontaneous mutation rate of KU-7 varied with temperature. The increase with 1 0 C increment of mean temperature was -0.04%. Uses of Tradescantia in monitoring the environmental radiation is discussed. (auth.)

  2. Comparative measurements of external radiation exposure using mobile phones, dental ceramic, household salt and conventional personal dosemeters

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Bulánek, Boris; Judas, Libor

    2015-01-01

    Because retrospective dosimetry utilises commonly occurring materials and objects, it is particularly useful in cases of large-scale radiation accidents or malevolent acts with radioactive materials where casualties are inflicted on the general public and first emergency responders. The aim of this study was to investigate whether retrospective dosemeters can provide dose estimates with comparable accuracy like conventional personal dosemeters. Using an external source of radiation 137 Cs and an anthropomorphic phantom, we simulated serious irradiation of a human body in anterior-posterior and rotational geometries. Retrospective luminescence dosimetry objects, such as mobile phones, dental ceramic and household salt, and conventional personal dosemeters (thermoluminescent and electronic) were fixed to the anthropomorphic phantom. The doses obtained were compared with specific reference values. In most cases, relative deviations between the measured doses and the reference values did not exceed 20%. As the retrospective and conventional dosemeters show no significant differences in laboratory conditions, the retrospective luminescence dosimetry objects represent a very promising tool if handled properly. - Highlights: • A serious external exposure of human body was simulated. • Doses were measured using both retrospective and conventional dosemeters. • Utilised retrospective dosimetry materials were alumina resistors from mobile phones, household salt and dental ceramic. • Doses obtained were compared with reference values. • Both retrospective and conventional dosemeters gave similar results

  3. Evaluation of the occupational exposure to external sources of ionizing radiation in Cuba in the period 2001-2005

    International Nuclear Information System (INIS)

    Molina P, D.; Martinez H, E.; Castro S, A.

    2006-01-01

    The single radiological surveillance of the occupational exposure to external radiation sources in Cuba it is carried out by the Radiation Protection and Hygiene Center (CPHR). The data corresponding to the external exposure are presented. The service it covers to all the occupationally exposed workers (TOEs) of the country that work fundamentally the radiodiagnostic practices, nuclear medicine, radiotherapy and research. The purpose of this work is to carry out an analysis of the occupational exposures of the TOE of the country starting of the results registered by the service of single radiological surveillance in the period 2001 to 2005, keeping in mind the indicators used by the UNSCEAR. The annual average effective dose (E) for each practice is shown. The obtained results showed that the values of annual average effective dose (E) its are bigger for the radiodiagnostic practices, radiotherapy and nuclear medicine. In a general way, all the E values are inferior to 2.00 mSv. The number of TOEs that overcame the 20 mSv established as annual dose limit, it went inferior to 1% of the controlled total universe. (Author)

  4. Studies on occupational exposure to external radiation at Fukuoka University Hospital

    International Nuclear Information System (INIS)

    Miyauchi, Teiichi; Oshima, Yoshio; Ono, Yo

    1982-01-01

    This is a report of the yearly changes of exposure received by workers in radiological occupations at Fukuoka University Hospital from August 1973 to December 1980. The total number of the workers during this period involving diagnostic radiology, radiotherapy and the other related fields included 153 physicians, 27 technicians, 29 nurses and 16 assistants. Out of 225 workers, only two angiographers and two involved in intracavitary radiation therapy received more than 500 mrem of the annual exposure dose. The highest dose was 610 mrem. The exposure doses have gradually decreased each year. The exposure of the workers has remarkably decreased to almost negligible since a remote afterloading system was installed for intracavitary radiation therapy. In no worker was any somatic effect of radiation detected in the periodical physical examinations, even in the number of lymphocytes in the peripheral blood. (author)

  5. 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)

  6. Studies on occupational exposure to external radiation at Fukuoka University Hospital

    Energy Technology Data Exchange (ETDEWEB)

    Miyauchi, Teiichi; Oshima, Yoshio; Ono, Yo [Fukuoka Univ. (Japan)

    1982-09-01

    This is a report of the yearly changes of exposure received by workers in radiological occupations at Fukuoka University Hospital from August 1973 to December 1980. The total number of the workers during this period involving diagnostic radiology, radiotherapy and the other related fields included 153 physicians, 27 technicians, 29 nurses and 16 assistants. Out of 225 workers, only two angiographers and two involved in intracavitary radiation therapy received more than 500 mrem of the annual exposure dose. The highest dose was 610 mrem. The exposure doses have gradually decreased each year. The exposure of the workers has remarkably decreased to almost negligible since a remote afterloading system was installed for intracavitary radiation therapy. In no worker was any somatic effect of radiation detected in the periodical physical examinations, even in the number of lymphocytes in the peripheral blood.

  7. Investigation of environmental natural penetrating radiation level in inner mongolia

    International Nuclear Information System (INIS)

    Li Wenyuan; Du Xuelin; Zhang Baozhong; Fu Su; Chen Jun; Zhang Wenhai

    1990-01-01

    The scheme, quality assurance measure, and results for environmental natural penetrating radiation level investigation in Inner Mongolia Autonomous Region was reported. Over the whole Region area of more than 1.18 million km 2 , 1018 net grid measuring points were selected with grid spacing of 25 x 25 km. The range of natural environmental terrestrial γ-radiation air absorbed dose rate over fields was (0.96-18.62) x 10 -8 Gy·h -1 , the range of γ-radiatoin dose rate over road was (1.07-26.08) x 10 -8 Gy·h -1 , the mean was 5.92 x 10 -8 Gy·h -1 ; the range of γ-radiation dose rate in buildings was (3.82-18.94) x 10 -8 Gy·h -1 ; the range of outdoor air absorbed dose rate caused by ionization compnents of cosmic rays was (3.12-5.55) x 10 -8 Gy·h -1 , while indoor range was (2.60-4.66) x 10 -8 Gy·h -1 ; the range of outdoor natural penetrating radiation dose rate was (8.31-11.26) x 10 -8 Gy·h -1 , indoor range was (11.20-14.67) x 10 -8 Gy·h -1 ; annual average individual effective dose equivalent and annual collective effective dose equivalent caused by natural penetrating radiatoin were 0.84 mSv and 1.61 x 10 4 man·Sv respectively. The georgaphical distribution of terrestrial γ-radiation dose rate within all region was reprted, the increase of environmental terrestial γ-radiation caused by human activity was also pointed. This ought to be paid enough attention to

  8. Muscle invasive bladder cancer treated by transurethral resection, followed by external beam radiation and interstitial iridium-192

    International Nuclear Information System (INIS)

    Wijnmaalen, Arendjan; Helle, Peter A.; Koper, Peter C.M.; Jansen, Peter P.; Hanssens, Patrick E.J.; Boeken Kruger, Cornelis G.G.; Putten, Wim L.J. van

    1996-01-01

    Purpose: In our center interstitial radiation has played an important role in the treatment of bladder cancer patients for over 40 years. Radium needles, that were initially used, were replaced by caesium needles in 1983, whereas the afterloading iridium wire technique was adopted in 1989. Patients with solitary tumors (T1, T2 and T3) with a surface diameter of < 5 cm are considered for interstitial radiation. In this study we report on the results of the afterloading iridium wire technique in patients with muscle invasive bladder cancer. Materials and Methods: From May 1989 to September 1993 interstitial radiation using iridium wires was part of the treatment in 46 patients with muscle invasive bladder cancer (37 T2, 9 T3). The mean age was 67 years. After transurethral resection of all visible tumor (if possible), in most cases 40 Gy (20 x 2.0 Gy, midplane dose) external beam radiation was delivered to the true pelvis, followed by 30 Gy interstitial radiation using iridium-192 wires covering the tumor area in the bladder. Results: After a median follow-up of 26 months, bladder relapses occurred in 7 patients. In 5 of them the tumor relapsed in the initial area, in 1 patient elsewhere in the bladder and in 1 patient tumor recurred in and outside the initial site. Recurrence was superficial (T1) in 4 patients. A relapse in the urethra was found once. Metastases developed in 13 patients, in 8 without bladder relapse. During the observation period 17 patients died, 13 due to bladder cancer. The actuarial bladder relapse-free survival at 4 years was 74% and 82% for T2 and T3 tumors, respectively. The actuarial distant metastases-free survival was 65% for both categories. No serious toxicity was recorded. Conclusion: In a selected group of patients with muscle invasive bladder cancer transurethral resection in combination with external beam and interstitial radiation provides an excellent opportunity to preserve the bladder with a high chance of success. Development of

  9. External Validation and Optimization of International Consensus Clinical Target Volumes for Adjuvant Radiation Therapy in Bladder Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Abhinav V. [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States); Christodouleas, John P. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Wu, Tianming [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States); Smith, Norman D.; Steinberg, Gary D. [Section of Urology, Department of Surgery, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States); Liauw, Stanley L., E-mail: sliauw@radonc.uchicago.edu [Department of Radiation and Cellular Oncology, University of Chicago Pritzker School of Medicine, Chicago, Illinois (United States)

    2017-03-15

    Purpose: International consensus (IC) clinical target volumes (CTVs) have been proposed to standardize radiation field design in the treatment of patients at high risk of locoregional failure (LRF) after radical cystectomy. The purpose of this study was to externally validate the IC CTVs in a cohort of postsurgical patients followed up for LRF and identify revisions that might improve the IC CTVs' performance. Methods and Materials: Among 334 patients with pT3 to pT4 bladder cancer treated with radical cystectomy, LRF developed in 58 (17%), of whom 52 had computed tomography scans available for review. Images with LRF were exported into a treatment planning system, and IC CTVs were contoured and evaluated for adequacy of coverage of each LRF with respect to both the patient and each of 6 pelvic subsites: common iliac (CI) region, obturator region (OR), external and internal iliac region, presacral region, cystectomy bed, or other pelvic site. Revisions to the IC contours were proposed based on the findings. Results: Of the 52 patients with documented LRF, 13 (25%) had LRFs that were outside of the IC CTV involving 17 pelvic subsites: 5 near the CI CTV, 5 near the OR CTV, 1 near the external and internal iliac region, and 6 near the cystectomy bed. The 5 CI failures were located superior to the CTV, and the 5 OR failures were located medial to the CTV. Increasing the superior boundary of the CI to a vessel-based definition of the aortic bifurcation, as well as increasing the medial extension of the OR by an additional 9 mm, decreased the number of patients with LRF outside of the IC CTV to 7 (13%). Conclusions: Modified IC CTVs inclusive of a slight adjustment superiorly for the CI region and medially for the OR may reduce the risk of pelvic failure in patients treated with adjuvant radiation therapy.

  10. Radiological protection. Technical recommendations for monitoring the exposure of individuals to external radiation

    International Nuclear Information System (INIS)

    1975-01-01

    Advice is given on the assessment of personal doses received by each worker. The objectives of individual monitoring programs and the requirements which personal dosemeters should satisfy are given. The paper is mainly concerned with assessment of doses due to photon and electron radiations

  11. Indoor External Radiation Risk in Densely Populated Regions of Southern Nigeria

    Science.gov (United States)

    Ife-Adediran, Oluwatobi O.; Uwadiae, Iyobosa B.

    2018-05-01

    It is known that certain types of building materials contain significant concentrations of natural radionuclides; consequently, exposure to indoor background radiation is from the combined radioactivity from the soil as well as building materials; indoor exposures therefore have higher radiation hazard potentials than outdoor exposures in this regard and hence, need to be monitored. In this paper, an evaluation of background ionizing radiation from different buildings in Lagos and Ibadan, Southwestern Nigeria was carried out to determine the exposure rate of the general public to indoor ionizing radiation. 630 in situ measurements from the different buildings were taken using a Geiger Muller counter (model GQ-320 Plus). The indoor dose rates (i.e., 50-120 nGy/h) were within the world average values while the Annual Effective Dose for most of the buildings were above the world average AED for indoor gamma exposure from building materials. The mean AED for Lagos and Ibadan due to indoor exposures were 0.37 and 0.39 mSv/y with Excess Lifetime Cancer Risk of 0.99E-3 and 1.05E-3, respectively.

  12. Investigation of environmental natural penetrating radiation level in Beijing

    International Nuclear Information System (INIS)

    Wu Zengxin; Zhang Wenying; Zheng Rukuan; Wei Shujun; Ding Huiqiu

    1992-01-01

    The authors report the methods and results of investigation of environmental natural penetrating radiation level in Beijing. There were 83 measurement points selected, which were located at the vertexes of 1 x 1 km square meshes and uniformly distributed over the urban district. 173 net grid measuring points selected with grid spacing of 10 x 10 km and uniformly distributed over the suburban district. Another 131 more densely distributed points were added over some special areas. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate over field is 56.2, 56.4 and 50.1 nGy · h -1 respectively. The γ radiation dose rate is higher in west and north area than in southeast area. (2) The point-weighted average value of natural γ radiation dose rate over roads was 49.3 nGy · h -1 . (3) The point weighted and population-weighted average value of natural γ radiation dose inside buildings was 83.5 and 77.1 nGy · h -1 respectively. (4) The weighted average of air absorbed dose rate from the ionizing components of cosmic rays (except for neutron) over point number and population was respectively 29.0 and 27.5 nGy · h -1 indoors, and 32.3 and 30.8 nGy · h -1 outdoors. (5) The point and population-weighted means of natural penetrating radiation dose rate (the contribution from neutron is not included) are 112.8 and 104.5 nGy · h -1 indoors, respectively; 88.7 and 81.3 nGy · h -1 outdoors, respectively. (6) The annual effective dose equivalent per capital people natural γ radiation, cosmic ray and natural penetrating radiation was 0.43, 0.25 and 0.68 mSv respectively, and the annual collective effective dose equivalent was 4.0, 2.3 and 6.3 x 10 3 man · Sv, respectively

  13. Legal aspects of radiation protection at the international level

    International Nuclear Information System (INIS)

    Papazian, J.

    1981-01-01

    A review is made of the respective activities of the various international organizations concerned with radiation protection at the legal level. These organizations are either non-governmental (I.C.R.P., I.C.R.U.) or governmental in which case they can act at the world (U.N., I.A.E.A., I.L.O., W.H.O.) or regional level (N.E.A., EURATOM, COMECOM). The legal impact of the recommendations or directives they issue is specified [fr

  14. Genetic damage from low-level and natural background radiation

    International Nuclear Information System (INIS)

    Oftedal, P.

    1988-01-01

    Relevant predictions that have been made of possible low level biological effects on man are reviewed, and the estimate of genetic damage is discussed. It is concluded that in spite of a number of attempts, no clear-cut case of effects in human populations of radiation at natural levels has been demonstrated. The stability of genetic material is dynamic, with damage, repair and selection running as continuous processes. Genetic materials are well protected and are conservative in the extreme, not least because evolution by genetic adaptation is an expensive process: Substitution of one allele A 1 by another A 2 means the death of the whole A 1 population

  15. Statistical Modeling of the Eye for Multimodal Treatment Planning for External Beam Radiation Therapy of Intraocular Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Rueegsegger, Michael B. [ARTORG Center for Biomedical Engineering Research, University of Bern (Switzerland); Bach Cuadra, Meritxell [Department of Radiology, University Hospital Center (CHUV) and University of Lausanne (UNIL), Signal Processing Laboratory - LTS5, Ecole Polytechnique Federale de Lausanne (Switzerland); Pica, Alessia [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland); Amstutz, Christoph A. [Department of Ophthalmology, University Hospital Zurich (Switzerland); Rudolph, Tobias [ARTORG Center for Biomedical Engineering Research, University of Bern (Switzerland); Aebersold, Daniel [Department of Radiation Oncology, Inselspital, Bern University Hospital, and University of Bern (Switzerland); Kowal, Jens H., E-mail: jens.kowal@artorg.unibe.ch [ARTORG Center for Biomedical Engineering Research, University of Bern (Switzerland)

    2012-11-15

    Purpose: Ocular anatomy and radiation-associated toxicities provide unique challenges for external beam radiation therapy. For treatment planning, precise modeling of organs at risk and tumor volume are crucial. Development of a precise eye model and automatic adaptation of this model to patients' anatomy remain problematic because of organ shape variability. This work introduces the application of a 3-dimensional (3D) statistical shape model as a novel method for precise eye modeling for external beam radiation therapy of intraocular tumors. Methods and Materials: Manual and automatic segmentations were compared for 17 patients, based on head computed tomography (CT) volume scans. A 3D statistical shape model of the cornea, lens, and sclera as well as of the optic disc position was developed. Furthermore, an active shape model was built to enable automatic fitting of the eye model to CT slice stacks. Cross-validation was performed based on leave-one-out tests for all training shapes by measuring dice coefficients and mean segmentation errors between automatic segmentation and manual segmentation by an expert. Results: Cross-validation revealed a dice similarity of 95% {+-} 2% for the sclera and cornea and 91% {+-} 2% for the lens. Overall, mean segmentation error was found to be 0.3 {+-} 0.1 mm. Average segmentation time was 14 {+-} 2 s on a standard personal computer. Conclusions: Our results show that the solution presented outperforms state-of-the-art methods in terms of accuracy, reliability, and robustness. Moreover, the eye model shape as well as its variability is learned from a training set rather than by making shape assumptions (eg, as with the spherical or elliptical model). Therefore, the model appears to be capable of modeling nonspherically and nonelliptically shaped eyes.

  16. 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

  17. Treatment of bulky stage IB and IIB cervical cancers with outpatient neutron brachytherapy, external pelvic radiation and extrafascial hysterectomy

    International Nuclear Information System (INIS)

    Van Nagell, J.R.; Maruyama, Y.; Yoneda, J.; Donaldson, E.S.; Hanson, M.B.; Gallion, H.H.; Powell, D.E.; Kryscio, R.J.

    1986-01-01

    From January, 1977, to December, 1982, twenty-nine patients with bulky (>4 cms diameter) Stage IB or IIB cervical cancer were treated at the University of Kentucky Medical Center by a combination of out-patient neutron brachytherapy (Cf-252) and external pelvic radiation followed by extrafascial hysterectomy. Residual tumor was present in the hysterectomy specimens of 25 per cent. Complications during and following radiation therapy and surgery were minimal and included vaginal stenosis, proctitis, and hemorrhagic cystitis. The mean duration of hospitalization for surgery in these patients was 6.6 days (range 5-15 days) and postoperative morbidity was low. No patient required blood transfusion. Four patients developed urinary tract infections and two had superficial wound separations. Following treatment, patients were seen at monthly intervals for one year, every three months for two years, and every six months thereafter. No patient has been lost to follow-up. Two patients (7 per cent) developed tumor recurrence and have died of disease (1 of distant metastases; 1 local). The remaining 27 patients (93 per cent) are alive and well with no evidence of disease 24-89 months (mean 48 months) after therapy. No radiogenic fistulae or bowel obstruction were observed. These preliminary results suggest that the combination of outpatient neutron brachytherapy, external pelvic radiation, and extrafascial hysterectomy for patients with Stage IB and IIB cervical cancer is well tolerated. Complications associated with this treatment regimen have been minimal, and the recurrence rate is low. The duration of intracavitary neutron brachytherapy was short, and outpatient therapy was well received by patients

  18. Statistical modeling of the eye for multimodal treatment planning for external beam radiation therapy of intraocular tumors.

    Science.gov (United States)

    Rüegsegger, Michael B; Bach Cuadra, Meritxell; Pica, Alessia; Amstutz, Christoph A; Rudolph, Tobias; Aebersold, Daniel; Kowal, Jens H

    2012-11-15

    Ocular anatomy and radiation-associated toxicities provide unique challenges for external beam radiation therapy. For treatment planning, precise modeling of organs at risk and tumor volume are crucial. Development of a precise eye model and automatic adaptation of this model to patients' anatomy remain problematic because of organ shape variability. This work introduces the application of a 3-dimensional (3D) statistical shape model as a novel method for precise eye modeling for external beam radiation therapy of intraocular tumors. Manual and automatic segmentations were compared for 17 patients, based on head computed tomography (CT) volume scans. A 3D statistical shape model of the cornea, lens, and sclera as well as of the optic disc position was developed. Furthermore, an active shape model was built to enable automatic fitting of the eye model to CT slice stacks. Cross-validation was performed based on leave-one-out tests for all training shapes by measuring dice coefficients and mean segmentation errors between automatic segmentation and manual segmentation by an expert. Cross-validation revealed a dice similarity of 95%±2% for the sclera and cornea and 91%±2% for the lens. Overall, mean segmentation error was found to be 0.3±0.1 mm. Average segmentation time was 14±2 s on a standard personal computer. Our results show that the solution presented outperforms state-of-the-art methods in terms of accuracy, reliability, and robustness. Moreover, the eye model shape as well as its variability is learned from a training set rather than by making shape assumptions (eg, as with the spherical or elliptical model). Therefore, the model appears to be capable of modeling nonspherically and nonelliptically shaped eyes. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. American Brachytherapy Society Task Group Report: Combination of brachytherapy and external beam radiation for high-risk prostate cancer.

    Science.gov (United States)

    Spratt, Daniel E; Soni, Payal D; McLaughlin, Patrick W; Merrick, Gregory S; Stock, Richard G; Blasko, John C; Zelefsky, Michael J

    To review outcomes for high-risk prostate cancer treated with combined modality radiation therapy (CMRT) utilizing external beam radiation therapy (EBRT) with a brachytherapy boost. The available literature for high-risk prostate cancer treated with combined modality radiation therapy was reviewed and summarized. At this time, the literature suggests that the majority of high-risk cancers are curable with multimodal treatment. Several large retrospective studies and three prospective randomized trials comparing CMRT to dose-escalated EBRT have demonstrated superior biochemical control with CMRT. Longer followup of the randomized trials will be required to determine if this will translate to a benefit in metastasis-free survival, disease-specific survival, and overall survival. Although greater toxicity has been associated with CMRT compared to EBRT, recent studies suggest that technological advances that allow better definition and sparing of critical adjacent structures as well as increasing experience with brachytherapy have improved implant quality and the toxicity profile of brachytherapy. The role of androgen deprivation therapy is well established in the external beam literature for high-risk disease, but there is controversy regarding the applicability of these data in the setting of dose escalation. At this time, there is not sufficient evidence for the omission of androgen deprivation therapy with dose escalation in this population. Comparisons with surgery remain limited by differences in patient selection, but the evidence would suggest better disease control with CMRT compared to surgery alone. Due to a series of technological advances, modern combination series have demonstrated unparalleled rates of disease control in the high-risk population. Given the evidence from recent randomized trials, combination therapy may become the standard of care for high-risk cancers. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All

  20. Ultrasonically guided 125iodine seed implantation with external radiation in management of localized prostatic carcinoma

    DEFF Research Database (Denmark)

    Iversen, P; Bak, M; Juul, N

    1989-01-01

    Thirty-three patients with localized prostatic carcinoma (16 poorly differentiated) were treated with transperineal 125Iodine seed implantation (160 Gy) guided by transrectal ultrasonography and subsequent external beam irradiation (47.4 Gy). The observation time was six to sixty-eight months...... with a median follow-up of thirty-five months. Median change in prostatic volume was a reduction of 35 percent. Re-biopsy or transurethral resection of the prostate was performed in 25 patients after one to two years, revealing still malignant histology in 12 (48%). Development of distant metastases occurred...

  1. The evaluation of radiation level and dose of workers in Guangzhou metro line 1

    International Nuclear Information System (INIS)

    Zhang Lin; Hu Canyun; Meng Xiaolian; He Zhan

    2006-01-01

    Objective: To find out the level of radiation and effective dose of workers in Guangzhou Metro line 1. Methods: In metro stations, external Gamma-ray exposure rates were obtained by FD-71A radiance measurer, 222 Rn and 220 Rn concentrations were obtained by using Rn-Tn solid state nuclear track detectors developed by The National Institute for Radiological Protection and Nuclear Safety, Chinese Centre for Disease Control. The annual Effective dose from Gamma, 222 Rn and 220 Rn were calculated. Results: The external Gamma-ray exposure average rate is 17.74 x 10 -8 Gy/h. The average concentration of 222 Rn is 59.8 Bq/m 3 . The average concentration of 220 Rn is 32.1 Bq/m 3 . The total annual effective dose from Gamma, 222 Rn and 220 Rn is 2.878 mSv/a. Conclusion: In the stations of Guangzhou in metro line 1, no more effective radiation dose to the workers has measured. (authors)

  2. Influence of ionizing radiation on gastrointestinal peptide levels

    Energy Technology Data Exchange (ETDEWEB)

    Wysocki, J.; Esposito, V.; Linard, C. [CEA Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire

    1997-03-01

    Exposure of the gut to ionising radiation may induce gastrointestinal damage and dysfunction. Early effects such as nausea, vomiting and diarrhea, anorexia may be observed within the first 24 h after irradiation. Such symptoms are seen even with doses as low as 1 Gy. later effects and the onset of the gastrointestinal syndrome are seen at higher doses (10 Gy) and include gastric emptying inhibition, intestinal hemorrhages, disturbances in water and electrolytes balance and septicemia. The severity of which depends on the nature, dose and dose rate received. The mechanism underlying these changes was unclear; it has long been known that exposure to ionising radiation affects intestinal morphology usually because of inhibition of mitotic activity at the level of the crypt enterocyst. The various physiological functions of the gastrointestinal tract are controlled by a wide variety of agents as neurotransmitters, neuropeptides. Radiation induces alterations in hormonal release and response. The present study carried out in the rat focuses on Gastrin Releasing Peptide (GRP), a gastrointestinal neuropeptide present in the central nervous system and in the gut endocrine cells were released into blood. The GRP controls food intake, pancreatic enzyme secretions, gastric emptying, intestinal motility and cellular proliferation. The aim was to investigate the effects of gamma and neutron/gamma on plasma and gastrointestinal tissue levels of GRP

  3. Environments with elevated radiation levels from natural radioactive substances

    International Nuclear Information System (INIS)

    Sohrabi, M.

    2000-01-01

    Some areas in the world have elevated levels of radioactive substances in the environment forming elevated radiation areas (ERAs) where public potential annual effective doses can exceed even the dose limit of radiation workers. Such radioactive substances are either terrestrial natural radioactivity added naturally in the soil or natural and/or man-made radioactivity from human activities added into the environment. If radioactivity is added naturally, elevated natural radiation areas (ENRAs) are formed. Based on the classification criteria introduced by the author, such regions are divided into static and dynamic areas. They are also classified in accordance with their level of potential effective dose to the public. Some main ENRAs are classified. Highlights are presented of the results of activity studies carried out in selected areas. The concepts discussed can also be applied to areas formed by human activities. The author suggests some guidelines for future studies, regulatory control and decision making, bearing in mind the need for harmonization of policies for regulatory control and remedial actions at sites to protect the public from environmental chronic exposures. (author)

  4. Investigation of environmental natural penetrating radiation level in Hebei province

    International Nuclear Information System (INIS)

    Zheng Deliang; Wang Shuming; Yang Huanfeng

    1990-01-01

    The methods and results of the investigation on natural penetrating radiation level in Hebei Province from 1985 to 1987 are presented. 285 25 x 25 km-netted measuring points were set unformly up all over the porvince, with 204 densely measuring points of different types added. The results show that: (1) The point-weighted, area-weighted and population-weighted average value of natural γ radiation dose rate for field is 5.59, 5.51 and 5.31 x 10 -8 Gy·h -1 , respectively; (2) The point-weighted and population-weighted average value of the dose rate inside buildings from cosmic ray is 3.05 and 2.80 x 10 -8 Gy·h -1 , and outside buildings is 3.38 and 3.11 x 10 -8 Gy·h -1 , respectively; (3) The point-weighted and population-weighted average value of natural penetrating radiation dose rate inside buildings is 12.44 and 11.97 x 10 -8 Gy·h -1 , outside buildings is 8.97 and 8.42 x 10 -8 Gy·h -1 , respectively; (4) The annual effective dose equivalent from natural γ radiation, cosmic ray and natural penetrating radiation is 0.50, 0.25, and 0.75 mSv, respectively; and correspondingly, the annual collective effectiv dose equivalent is 2.7, 1.3 and 4.0 x 10 4 man·Sv, respectively

  5. 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)

  6. Application of estimating effective dose from external radiation using two dosimeters during maintenance periods at KNPPS

    International Nuclear Information System (INIS)

    Kim, Hee Geun; Kong, Tae Young

    2008-01-01

    The application of a two-dosimeter and its algorithm and a test of its use in an inhomogeneous high radiation field are described. The goal was to develop an improved method for estimating the effective dose during maintenance periods at Korean nuclear power plants (NPPs). The use of the method in domestic and international NPPs including USA, Canada and Japan was also investigated. The algorithms used by the Canadian Ontario Power Generation (OPG) and American ANSI HPS N13.41, Lakshmanan, NCRP, EPRI and Texas A and M University were extensively analyzed as two-dosimeter algorithms. The possibility of their application to NPPs was evaluated using data for each algorithm from two-dosimeter results for an inhomogeneous high radiation field during maintenance periods at Korean NPPs. (author)

  7. Characteristics of silicon diodes as patient dosemeters in external radiation therapy

    International Nuclear Information System (INIS)

    Nilsson, B.; Sorcini, B.

    1988-01-01

    Silicon diodes connected to an integrating instrument that are used to measure the entrance dose on patients undergoing radiation therapy have been investigated with special emphasis on practical clinical aspects. The variation of the diode response for different photon qualities with different field sizes and different irradiation situations including oblique fields, wedges, blocking filters giving different electron contamination have been measured. The diode response for the different situations met in clinical practice when using various electron energies have also been examined. The results from measurements for patients treated with high energy are presented. The study has shown that if the mean value of all measured entrance doses with the diode on a patient differ more than ±3% from the presented absorbed dose for 60 Co gamma radiation, a correction of the given dose should be made. The corresponding figure for high energy X-rays is ±5%. 23 refs.; 6 figs.; 5 tabs

  8. 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

  9. Low-level multicounter {beta}/{gamma} systems with external guards in surface and shallow underground laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Theodorsson, P [Iceland Univ. (Iceland). Science Inst.

    1997-03-01

    When weak samples are measured it is important that they can be given ample counting time in order to obtain satisfactory accuracy and that the background count rate can be checked well. This calls for a high counting capacity, which multidetectors can bring us. I will discuss development possibilities of low-level {beta}/{gamma} multidetector systems with an external anticosmic shield that will in many cases be operated in underground laboratories. These simple and low-cost system can frequently help us in increasing the number of detectors. Three concepts are combined in these systems: (1) multidetectors, (2) an external anticosmic (or guard) detector arrangement and (3) overburden shielding. (orig.)

  10. Low-level multicounter β/γ systems with external guards in surface and shallow underground laboratories

    International Nuclear Information System (INIS)

    Theodorsson, P.

    1997-01-01

    When weak samples are measured it is important that they can be given ample counting time in order to obtain satisfactory accuracy and that the background count rate can be checked well. This calls for a high counting capacity, which multidetectors can bring us. I will discuss development possibilities of low-level β/γ multidetector systems with an external anticosmic shield that will in many cases be operated in underground laboratories. These simple and low-cost system can frequently help us in increasing the number of detectors. Three concepts are combined in these systems: (1) multidetectors, (2) an external anticosmic (or guard) detector arrangement and (3) overburden shielding. (orig.)

  11. Social economical and psychological considerations in conveying potential radiation risks from high level natural background radiation to the residents of Ramsar, Iran

    International Nuclear Information System (INIS)

    Mortazavi, S. M. J.; Ghiassi-nejad, M.

    2003-01-01

    X-rays and radioactivity were discovered more than 100 years ago but the need for protection against very low doses of ionizing radiation and especially different levels of natural radiation is still among the most controversial matters in radiobiology and radiation protection. According to formal reports, some areas in Ramsar, a city in northern Iran, are the inhabited areas with the highest levels of natural radiation studied so far. A population of about 2000 is exposed to average annual radiation levels of 10.2 mGy y''-1 and the highest recorded external gamma dose rates are about 130 mGy y''-1. We have previously shown that in high background radiation areas (HBRAs), cultured human lymphocytes of the inhabitants whose cumulative radiation doses were as much as 170 times more than those of a control area when subjected to 1.5 Gy challenge dose,were significantly more radioresistant compared to the residents of the control area (Mortazavi et al. 2002a,b, Mortazavi and Karam 2002, Ghiassi-Najed et al. 2002). The people who live in these areas are usually unaware of the high levels of natural radiation in their environment. Studies performed on the residents of these areas have indicated that the effective dose of the inhabitants, in some cases, is much higher than the dose limits for occupational irradiation. Considering recent policies of ICRP regarding suggesting dose limits for exposure to natural sources of ionizing including radon, it seems that the inhabitants should become familiar with the possible risks of the exposure to high levels of ionizing radiation. They should also realize that studies performed over the past years have indicated no detrimental effect. On the other hand, according to ICRP suggestions and considering the experiences in other countries, especially evacuation of the residents of contaminated areas after Chernobyl accident, setting any radiation protection regulation for the inhabitants without considering social, economic and

  12. 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...

  13. External Beam Radiotherapy of Recurrent Glioma: Radiation Tolerance of the Human Brain

    Energy Technology Data Exchange (ETDEWEB)

    Sminia, Peter, E-mail: p.sminia@vumc.nl [Department of Radiation Oncology, Radiobiology Section, VU University Medical Center, De Boelelaan 1117, P.O. Box 7057, Amsterdam (Netherlands); Mayer, Ramona [EBG MedAustron GmbH., Viktor Kaplan-Strasse 2, A-2700, Wiener Neustadt (Austria)

    2012-04-05

    Malignant gliomas relapse in close proximity to the resection site, which is the postoperatively irradiated volume. Studies on re-irradiation of glioma were examined regarding radiation-induced late adverse effects (i.e., brain tissue necrosis), to obtain information on the tolerance dose and treatment volume of normal human brain tissue. The studies were analyzed using the linear-quadratic model to express the re-irradiation tolerance in cumulative equivalent total doses when applied in 2 Gy fractions (EQD2{sub cumulative}). Analysis shows that the EQD2{sub cumulative} increases from conventional re-irradiation series to fractionated stereotactic radiotherapy (FSRT) to LINAC-based stereotactic radiosurgery (SRS). The mean time interval between primary radiotherapy and the re-irradiation course was shortened from 30 months for conventional re-irradiation to 17 and 10 months for FSRT and SRS, respectively. Following conventional re-irradiation, radiation-induced normal brain tissue necrosis occurred beyond an EQD2{sub cumulative} around 100 Gy. With increasing conformality of therapy, the smaller the treatment volume is, the higher the radiation dose that can be tolerated. Despite the dose escalation, no increase in late normal tissue toxicity was reported. On basis of our analysis, the use of particle therapy in the treatment of recurrent gliomas, because of the optimized physical dose distribution in the tumour and surrounding healthy brain tissue, should be considered for future clinical trials.

  14. External Beam Radiotherapy of Recurrent Glioma: Radiation Tolerance of the Human Brain

    Directory of Open Access Journals (Sweden)

    Peter Sminia

    2012-04-01

    Full Text Available Malignant gliomas relapse in close proximity to the resection site, which is the postoperatively irradiated volume. Studies on re-irradiation of glioma were examined regarding radiation-induced late adverse effects (i.e., brain tissue necrosis, to obtain information on the tolerance dose and treatment volume of normal human brain tissue. The studies were analyzed using the linear-quadratic model to express the re-irradiation tolerance in cumulative equivalent total doses when applied in 2 Gy fractions (EQD2cumulative. Analysis shows that the EQD2cumulative increases from conventional re-irradiation series to fractionated stereotactic radiotherapy (FSRT to LINAC-based stereotactic radiosurgery (SRS. The mean time interval between primary radiotherapy and the re-irradiation course was shortened from 30 months for conventional re-irradiation to 17 and 10 months for FSRT and SRS, respectively. Following conventional re-irradiation, radiation-induced normal brain tissue necrosis occurred beyond an EQD2cumulative around 100 Gy. With increasing conformality of therapy, the smaller the treatment volume is, the higher the radiation dose that can be tolerated. Despite the dose escalation, no increase in late normal tissue toxicity was reported. On basis of our analysis, the use of particle therapy in the treatment of recurrent gliomas, because of the optimized physical dose distribution in the tumour and surrounding healthy brain tissue, should be considered for future clinical trials.

  15. Dose response curves for effects of low-level radiation

    International Nuclear Information System (INIS)

    Myers, D.K.

    1980-01-01

    The linear dose-response model used by international committees to assess the genetic and carcinogenic hazards of low-level radiation appears to be the most reasonable interpretation of the available scientific data that are relevant to this topic. There are, of course, reasons to believe that this model may overestimate radiation hazards in certain instances, a fact acknowledged in recent reports of these committees. The linear model is now also being utilized to estimate the potential carcinogenic hazards of other agents such as asbestos and polycyclic aromatic hydrocarbons. This model implies that there is no safe dose for any of these agents and that potential health hazards will increase in direct proportion to total accumulated dose. The practical implication is the recommendation that all exposures should be kept 'as low as reasonably achievable, economic and social factors being taken into account'. (auth)

  16. Evaluation of the radiation levels in different surgical procedures

    International Nuclear Information System (INIS)

    Silva Santos, M.C.P. da; Almeida, A. de; Belluci, A.D.; Ghilardi Neto, T.

    1989-01-01

    The exposure of a medical team to radiation during surgical procedures evidently depends on the duration and difficulties of the particular procedure. We have made a dosimetric study of the average equivalent doses received by the surgical teams during 10 different surgical procedures over a period of one month. Our results demonstrate that the levels of ionizing radiation that the members of the teams receive typically do not surpass the limits stipulated for the following surgical procedures: nefrolithotomy, percutaneous ureterolithomy, ureteroscoy connected with removal of stones in the inferior third of the ureter, osteosynthesis of the tibial plateau together with a articular toalet and minireconstruction of the knee. For compound surgical procedures, for example, osteosynthesis of a femur fracture together with biopsy of an exposed femur or percutaneous nefrolithotomy (complex cases), the dose limits have been surpassed owing to the additional fluoroscopy needed in those p rocedures. (author) [pt

  17. Phantom study of radiation doses outside the target volume brachytherapy versus external radiotherapy of early breast cancer

    International Nuclear Information System (INIS)

    Johansson, Bengt; Persson, Essie; Westman, Gunnar; Persliden, Jan

    2003-01-01

    Background and purpose: Brachytherapy is sometimes suggested as an adjuvant treatment after surgery of some tumours. When introducing this, it would be useful to have an estimate of the dose distribution to different body sites, both near and distant to target, comparing conventional external irradiation to brachytherapy. The aim of the present study was to determine radiation doses with both methods at different body sites, near and distant to target, in an experimental situation on an operated left sided breast cancer on a female Alderson phantom. Methods: Five external beam treatments with isocentric tangential fields were given by a linear accelerator. A specified dose of 1.0 Gy was given to the whole left sided breast volume. Five interstitial brachytherapy treatments were given to the upper, lateral quadrant of the left breast by a two plane, 10 needles implant. A dose of 1.0 Gy specified according to the Paris system was administered by a pulsed dose rate afterloading machine. Absorbed dose in different fixed dose points were measured by thermoluminescence dosimeters. Results: Both methods yielded an absorbed dose of the same size to the bone marrow and internal organs distant to target, 1.0-1.4% of the prescribed dose. There was a trend of lower doses to the lower half of the trunk and higher doses to the upper half of the trunk, respectively, by brachytherapy. A 90% reduction of absorbed dose with brachytherapy compared to external irradiation was found in the near-target region within 5 cm from target boundary where parts of the left lung and the heart are situated. If an adjuvant dose of 50 Gy is given with the external radiotherapy and brachytherapy, the absorbed dose in a part of the myocardium could be reduced from 31.8 to 2.1 Gy. Conclusions: Near target, brachytherapy yielded a considerably lower absorbed dose which is of special importance when considering radiation effects on the myocard and lungs. We could not demonstrate any difference of

  18. The Perceived Impact of External Evaluation: The System, Organisation and Individual Levels-Estonian Case

    Science.gov (United States)

    Seema, Riin; Udam, Maiki; Mattisen, Heli; Lauri, Liia

    2017-01-01

    The purpose of this article is to provide an overview of how the employees of higher education institutions perceive the impact of external evaluations. The study was conducted using the concurrent mixed method and involved 361 employees from Estonian universities and professional higher education institutions. The results indicated that…

  19. Teaching with External Representations: The Case of a Common Energy-Level Diagram in Chemistry

    Science.gov (United States)

    Orgill, MaryKay; Crippen, Kent

    2010-01-01

    Diagrams and figures play a central role in science and science education. Research has indicated that, when presented and used properly in a classroom setting, these external representations can contribute to students' understanding of scientific concepts; however, it is apparent that students do not always use, understand, interpret, or value…

  20. Energy levels, lifetimes and radiative data of W LV

    Science.gov (United States)

    Ding, Xiao-bin; Sun, Rui; Koike, Fumihiro; Murakami, Izumi; Kato, Daiji; Sakaue, Hiroyuki A.; Nakamura, Nobuyuki; Dong, Chen-zhong

    2018-01-01

    Calculations of energy levels, radiative data and lifetimes are reported for tungsten Ca-like ion (W LV) by using multi-configuration Dirac-Fock (MCDF) method. The GRASP2K package is adopted to carry out a large-scale systematic computation with a restricted active space treatment; the Breit interaction and QED effects are included in subsequent relativistic configuration interaction calculations. The energies and lifetimes of the lowest 119 levels are listed; the main leading configuration of the levels is of the ground state configuration [Ne]3s23p63d2 and the first excited configuration [Ne]3s23p53d3. The wavelengths, radiative rates and oscillator strengths for relatively strong E1, E2, M1, and M2 transitions are listed. Comparisons with earlier experimental and theoretical values are made. The average relative deviations of energy levels from the NIST results and E1 transition wavelengths from the EBIT experimental results have turned to be only 0.20% and 0.13%, respectively. The other present results are in reasonable agreement with available data. These agreements confirm the reliability and accuracy of the current results. The present datasets may help us with the investigation of the electron-electron correlation effects in complex multi-electron highly charged heavy ions and of the diagnosis of tungsten impurity plasmas in fusion science.

  1. 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.

  2. Temperature rise, sea level rise and increased radiative forcing - an application of cointegration methods

    Science.gov (United States)

    Schmith, Torben; Thejll, Peter; Johansen, Søren

    2016-04-01

    We analyse the statistical relationship between changes in global temperature, global steric sea level and radiative forcing in order to reveal causal relationships. There are in this, however, potential pitfalls due to the trending nature of the time series. We therefore apply a statistical method called cointegration analysis, originating from the field of econometrics, which is able to correctly handle the analysis of series with trends and other long-range dependencies. Further, we find a relationship between steric sea level and temperature and find that temperature causally depends on the steric sea level, which can be understood as a consequence of the large heat capacity of the ocean. This result is obtained both when analyzing observed data and data from a CMIP5 historical model run. Finally, we find that in the data from the historical run, the steric sea level, in turn, is driven by the external forcing. Finally, we demonstrate that combining these two results can lead to a novel estimate of radiative forcing back in time based on observations.

  3. Ambient radioactivity levels and radiation doses. Annual report 2009

    International Nuclear Information System (INIS)

    Bernhard-Stroel, Claudia; Hachenburger, Claudia; Trugenberger-Schnabel, Angela; Peter, Josef

    2010-12-01

    The annual report on environmental radioactivity and radiation exposure 2009 consists of two parts. Part A: General information: natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposures from medical applications, the handlin