WorldWideScience

Sample records for 50-year-old linear-no-threshold radiation

  1. Radiation hormesis and the linear-no-threshold assumption

    CERN Document Server

    Sanders, Charles L

    2009-01-01

    Current radiation protection standards are based upon the application of the linear no-threshold (LNT) assumption, which considers that even very low doses of ionizing radiation can cause cancer. The radiation hormesis hypothesis, by contrast, proposes that low-dose ionizing radiation is beneficial. In this book, the author examines all facets of radiation hormesis in detail, including the history of the concept and mechanisms, and presents comprehensive, up-to-date reviews for major cancer types. It is explained how low-dose radiation can in fact decrease all-cause and all-cancer mortality an

  2. Does Imaging Technology Cause Cancer? Debunking the Linear No-Threshold Model of Radiation Carcinogenesis.

    Science.gov (United States)

    Siegel, Jeffry A; Welsh, James S

    2016-04-01

    In the past several years, there has been a great deal of attention from the popular media focusing on the alleged carcinogenicity of low-dose radiation exposures received by patients undergoing medical imaging studies such as X-rays, computed tomography scans, and nuclear medicine scintigraphy. The media has based its reporting on the plethora of articles published in the scientific literature that claim that there is "no safe dose" of ionizing radiation, while essentially ignoring all the literature demonstrating the opposite point of view. But this reported "scientific" literature in turn bases its estimates of cancer induction on the linear no-threshold hypothesis of radiation carcinogenesis. The use of the linear no-threshold model has yielded hundreds of articles, all of which predict a definite carcinogenic effect of any dose of radiation, regardless of how small. Therefore, hospitals and professional societies have begun campaigns and policies aiming to reduce the use of certain medical imaging studies based on perceived risk:benefit ratio assumptions. However, as they are essentially all based on the linear no-threshold model of radiation carcinogenesis, the risk:benefit ratio models used to calculate the hazards of radiological imaging studies may be grossly inaccurate if the linear no-threshold hypothesis is wrong. Here, we review the myriad inadequacies of the linear no-threshold model and cast doubt on the various studies based on this overly simplistic model. © The Author(s) 2015.

  3. Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation?

    OpenAIRE

    Seong, Ki Moon; Seo, Songwon; Lee, Dalnim; Kim, Min-Jeong; Lee, Seung-Sook; Park, Sunhoo; Jin, Young Woo

    2016-01-01

    Inevitable human exposure to ionizing radiation from man-made sources has been increased with the proceeding of human civilization and consequently public concerns focus on the possible risk to human health. Moreover, Fukushima nuclear power plant accidents after the 2011 East-Japan earthquake and tsunami has brought the great fear and anxiety for the exposure of radiation at low levels, even much lower levels similar to natural background. Health effects of low dose radiation less than 100 m...

  4. Is the Linear No-Threshold Dose-Response Paradigm Still Necessary for the Assessment of Health Effects of Low Dose Radiation?

    Science.gov (United States)

    Seong, Ki Moon; Seo, Songwon; Lee, Dalnim; Kim, Min-Jeong; Lee, Seung-Sook; Park, Sunhoo; Jin, Young Woo

    2016-02-01

    Inevitable human exposure to ionizing radiation from man-made sources has been increased with the proceeding of human civilization and consequently public concerns focus on the possible risk to human health. Moreover, Fukushima nuclear power plant accidents after the 2011 East-Japan earthquake and tsunami has brought the great fear and anxiety for the exposure of radiation at low levels, even much lower levels similar to natural background. Health effects of low dose radiation less than 100 mSv have been debated whether they are beneficial or detrimental because sample sizes were not large enough to allow epidemiological detection of excess effects and there was lack of consistency among the available experimental data. We have reviewed an extensive literature on the low dose radiation effects in both radiation biology and epidemiology, and highlighted some of the controversies therein. This article could provide a reasonable view of utilizing radiation for human life and responding to the public questions about radiation risk. In addition, it suggests the necessity of integrated studies of radiobiology and epidemiology at the national level in order to collect more systematic and profound information about health effects of low dose radiation.

  5. The risk of low doses of ionising radiation and the linear no threshold relationship debate; La controverse sur les effets des faibles doses de rayonnements ionisants et la relation lineaire sans seuil

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M. [Centre Antoine Beclere, Faculte de Medecine, 75 - Paris (France); Masse, R. [11 rue du Haras, Residence Le Boqueteau, Acacias 2, 91 - Saint-Michel-sur-Orge (France); Vathaire, F. de [Institut Gustave Roussy, INSERM U 605., 94 - Villejuif (France); Averbeck, D. [Institut Curie, Section de Recherche, Lab. Raymond Latarjet, UMR2027 du CNRS, Centre Universitaire d' Orsay, 91 - Orsay (France); Aurengo, A. [Hopital Pitie-Salpetriere, Service Medecine Nucleaire, 75 - Paris (France)

    2007-04-15

    The ICRP and the B.E.I.R. VII reports recommend a linear no threshold (L.N.T.) relationship for the estimation of cancer excess risk induced by ionising radiations (IR), but the 2005 report of Medicine and Science French Academies concludes that it leads to overestimate of risk for low and very low doses. The bases of L.N.T. are challenged by recent biological and animal experimental studies which show that the defence against IR involves the cell microenvironment and the immunologic system. The defence mechanisms against low doses are different and comparatively more effective than for high doses. Cell death is predominant against low doses. DNA repairing is activated against high doses, in order to preserve tissue functions. These mechanisms provide for multicellular organisms an effective and low cost defence system. The differences between low and high doses defence mechanisms are obvious for alpha emitters which show several greys threshold effects. These differences result in an impairment of epidemiological studies which, for statistical power purpose, amalgamate high and low doses exposure data, since it would imply that cancer IR induction and defence mechanisms are similar in both cases. Low IR dose risk estimates should rely on specific epidemiological studies restricted to low dose exposures and taking precisely into account potential confounding factors. The preliminary synthesis of cohort studies for which low dose data (< 100 mSv) were available show no significant risk excess, neither for solid cancer nor for leukemias. (authors)

  6. Intervention reducing particle exposure in Homes of 50+ year olds

    DEFF Research Database (Denmark)

    Gunnarsen, Lars Bo; Spilak, Michal; Frederiksen, Marie

    2016-01-01

    An intervention reducing particle exposure was conducted in 27 apartments of 50+ year olds in Denmark. Two recirculating particle filtration units were installed in each apartment. They operated for two weeks in active filtration mode and for two weeks in sham mode in a randomized cross-over desi...

  7. The debate on the use of linear no threshold for assessing the effects of low doses

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M; Aurengo, A; Averbeck, D; Masse, R [Centre Antoine Beclere, 45 rue des Saints-Peres, 75006 Paris (France)

    2006-09-15

    From December 2004 to July 2005, three reports on the effects of low doses of ionising radiation were released: ICRP (2004), the joint report of the French Academies of Science and Medicine (Tubiana et al 2005), and a report from the American Academy of Sciences (BEIR VII 2005). These reports quote the same recent articles on the biological effects of low doses, yet their conclusions diverge. The French report concludes that recent biological data show that the efficacy of defense mechanisms is modulated by dose and dose rate and that linear no threshold (LNT) is no longer plausible. The ICRP and the BEIR VII reports recognise that there are biologic arguments against LNT but feel that there are not sufficient biological proofs against it to change risk assessment methodology and subsequent regulatory policy based on LNT. They point out the remaining uncertainties and the lack of mechanistic explanations of phenomena such as low dose hyperlethality or the adaptive response. In this context, a critical analysis of the available data is necessary. The epidemiological data and the experimental data challenge the validity of the LNT hypothesis for assessing the carcinogenic effect of low doses, but do not allow its exclusion. Therefore, the main criteria for selecting the most reliable dose-effect relationship from a scientific point of view should be based on biological data. Their analysis should help one to understand the current controversy. (opinion)

  8. The debate on the use of linear no threshold for assessing the effects of low doses.

    Science.gov (United States)

    Tubiana, M; Aurengo, A; Averbeck, D; Masse, R

    2006-09-01

    From December 2004 to July 2005, three reports on the effects of low doses of ionising radiation were released: ICRP (2004), the joint report of the French Academies of Science and Medicine (Tubiana et al 2005), and a report from the American Academy of Sciences (BEIR VII 2005). These reports quote the same recent articles on the biological effects of low doses, yet their conclusions diverge. The French report concludes that recent biological data show that the efficacy of defense mechanisms is modulated by dose and dose rate and that linear no threshold (LNT) is no longer plausible. The ICRP and the BEIR VII reports recognise that there are biologic arguments against LNT but feel that there are not sufficient biological proofs against it to change risk assessment methodology and subsequent regulatory policy based on LNT. They point out the remaining uncertainties and the lack of mechanistic explanations of phenomena such as low dose hyperlethality or the adaptive response. In this context, a critical analysis of the available data is necessary. The epidemiological data and the experimental data challenge the validity of the LNT hypothesis for assessing the carcinogenic effect of low doses, but do not allow its exclusion. Therefore, the main criteria for selecting the most reliable dose-effect relationship from a scientific point of view should be based on biological data. Their analysis should help one to understand the current controversy.

  9. [Assessment of fruit and vegetable intake among the 50-year-old population of Wroclaw].

    Science.gov (United States)

    Ilow, Rafał; Regulska-Ilow, Bozena; Misiewicz, Dominika; Rózańska, Dorota; Kowalisko, Alicja; Biernat, Jadwiga

    2011-01-01

    Intake of fruit and vegetable among 50-year-old population of Wroclaw and the impact of education level on the consumption of fruits and vegetables was assessed. The study group was 50-year-old, 1520 inhabitants of Wroclaw (879 women and 641 men), who participated in 2008 in the Cardiovascular Diseases Prevention Program organized by the Health Division of the Municipal Office in Wroclaw. To assess fruit and vegetable intake Food Frequency Questionnaire (FFQ) was used. The mean daily intake of vegetables and fruit was 289,4 g for women and 209,1 g for men. Women consumed significantly more vegetables, fruits, and the amounts of fruits and vegetables compared with men. The impact of educational level on fruit and vegetable consumption in the study group was found.

  10. [Characteristics of HIV infections among over 50-year-olds population in China].

    Science.gov (United States)

    Wang, L Y; Qin, Q Q; Ge, L; Ding, Z W; Cai, C; Guo, W; Cui, Y

    2016-02-01

    To analyze the characteristics on demographical, spatial distribution and transmission mode of HIV infections among 50-year-old population. Related information on demography, spatial distribution, high risk behavioral and history of HIV infections among 50-year-old population were collected and analyzed. Possible time of infection based on their first CD4 testing results right after the HIV diagnoses, was estimated. Since 2008, the number of new HIV/AIDS cases among the over-50-year-olds was reported increasing annually. The number of aged 50 and above in 2014 was 4.2 times than the number in 2008. 50-year-old or older population were infected mainly through heterosexual behavior (88.0%). Among these cases, 83.9% self-reported as having histories on extramarital sex intercourse and the number was increasing yearly. Among male cases who admitted as having heterosexual experience, 95.1% of them reported as having histories of extramarital sex intercourse while 53.4% of the female cases reported as having the same experiences. 46.6% of spouses of the females or with fixed partners were HIV positive. Through estimating the time of infection and the time interval between infection and diagnosis, we found that the proportion was 15.5%, from infection to diagnosis as 3 years among the 50 and older age groups, but the proportion of 8 years from infection to diagnosis was 43.6%. We estimated that 66.5% of the new HIV cases who were at age 50 and over, were infected when they were at that age span. The average time from infection and being tested was (6.8 ± 2.7) years. The increasing number of being diagnosed on HIV among the 50-year-olds population might be related to both high risk exposure and belated diagnoses among this population, calling for the necessity of deriving the sources of HIV infection and tailoring the HIV prevention strategies in this population.

  11. Ecological versus case-control studies for testing a linear-no threshold dose-response relationship.

    Science.gov (United States)

    Cohen, B L

    1990-09-01

    The two basic problems with ecological studies are (A) individuals studied are not necessarily the individuals who are at risk, and (B) they are very vulnerable to confounding factors. It is shown that where the study is designed to test a linear-no threshold dose-response theory, (A) does not apply. Where the ecological study deals with the average dose and response in a large number of US counties, the available data and computer capability for reducing effects of confounders are so powerful that (B) may be no more important for the ecological than for a case-control study. The migration problem is treated and found to be relatively unimportant.

  12. Prevalence of osteoporosis in women older than 50 years old in Bushehr port

    Directory of Open Access Journals (Sweden)

    Seyed Sajad Eghbali

    2009-02-01

    Full Text Available Background: Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone, leading to enhanced bone fragility. Prevalence of osteoporosis increases with age. The aim of this study was to estimate the prevalence of osteoporosis in women older than 50 years old in Bushehr port, irrespective of osteoporosis risk factors. Methods: A total of 406 women over 50 years old were selected from 13 cluster areas of Bushehr port using random sampling method. We used dual x-ray absorptimetry (DXA for measuring bone mineral density of femoral neck and lumbar areas. Demographic data, smoking, physical activity, daily intake of vitamin D and calcium, body mass index and waist to hip ratio were recorded for each women. Results: Mean BMDs of lumbar spine and femoral area were 0.944 (±0.844 g/cm2 and 0.842 (± 0.181 g/cm2, respectively. BMDs had a trend to decrease with increasing age (P<0.0001. The prevalence of osteopenia and osteoporosis in lumbar spine were 32.0% and 7.4%, respectively and the prevalence of osteopenia and osteoporosis in femur were 29.6% and 3.9%, respectively. No significant differences were observed between normal women and osteoporotic women in secondary osteoporosis risk factors. But osteoporotic women had more history of present or past smoking in comparison to normal women (P<0.05. Conclusion: Prevalence of osteopenia and osteoporosis in women older than 50 years old in Bushehr port is less than USA, Europe and Tehran populations.

  13. O’Brien’s Granuloma in a 50-year-old Chinese male

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    Huang Changzheng

    2015-07-01

    Full Text Available O’Brien’s actinic granuloma is clinically characterized by grouped red papules that may coalesce into annular plaques on sun damaged skin such as the head and neck, chest, and arms. There is no gender predilection, and patients tend to be middle-aged or older giving the association with significant actinic damage. We presented a 50-year-old male with multiple annular lesions on the neck of four years duration, associated with prolonged sun exposure. A biopsy confirmed the clinical suspicion of O’Brien’s granuloma and excluded other possibilities.

  14. Cardiomyopathy induced by pulmonary sequestration in a 50-year-old man.

    Science.gov (United States)

    Chatelain, Shaun; Comp, Robert A; Grace, R Randal; Sabbath, Adam M

    2015-02-01

    A 50-year-old black man presented at the emergency department with midsternal, nonradiating chest pressure and chronic dyspnea on exertion. Four years before the current admission, he had been diagnosed with nonischemic cardiomyopathy at another facility. After our complete evaluation, we suspected that his symptoms arose from left-to-left shunting in association with pulmonary sequestration, a congenital malformation. Our preliminary diagnosis of secondary dilated cardiomyopathy was confirmed by normalization of the patient's ventricular size and function after lobectomy. To our knowledge, this patient is the oldest on record to present with cardiomyopathy consequent to pulmonary sequestration. His case is highly unusual because of his age and the rapid resolution of his symptoms after lobectomy. We believe that pulmonary sequestration should be included in the differential diagnosis of dilated cardiomyopathy.

  15. Pure yolk sac tumor of testis in a 50 years old : A rare case report

    Directory of Open Access Journals (Sweden)

    Pradhan M Pagaro

    2016-01-01

    Full Text Available Yolk sac tumor (YST is most common in infants and children in age range of 3-8 years in pure form; however in adults, YST rarely occurs in pure form, but commonly occurs in association with other germ cell tumors as mixed forms. Less than 10 adult testicular pure YSTs have been reported in literature. We report a 50-year-old male with testicular neoplasm involving the left testis, with pain following trauma. Alpha-fetoprotein was markedly raised 5726 IU/ml, and on histopathology, characteristic features of YST with abundant Schiller–Duval bodies associated with reticular and microcystic pattern, and focal solid areas of nests and trabeculae of cuboidal cells, with prominent nucleoli and mitotic figures, were noted, and extensive histopathological search did not reveal presence of any other type of tumor.

  16. [Anxiety in a representative sample of the Spanish population over 50 years-old].

    Science.gov (United States)

    Carreira Capeáns, Cecilia; Facal, David

    Anxiety is common throughout the ageing process. The objective of this study is to estimate the prevalence of anxiety in a representative sample of the Spanish population over 50 years-old. The data of this study come from the Pilot Study developed within the Longitudinal Ageing Study in Spain (ELES), in which a representative sample of the non-institutionalised Spanish population was evaluated. An analysis was performed on the data of 1086 people who answered the question «I am now going to read a list with a series of diseases or health problems. I would like you to tell me if your doctor has diagnosed any of them». The tools used were a questionnaire consisting of 218 questions, along with standardised tests, such as the Spanish version of the Mini-Mental State Examination. Anxiety was reported to have been diagnosed at some time in 14.3% of the sample. The prevalence was higher in women than in men (77.8 vs. 22.2%), decreasing with age, and related to different chronic diseases. The results show that the prevalence of anxiety throughout the lifespan is noticeable in people over 50 years, and should be taken into account, especially in the female population and in those with chronic diseases. Copyright © 2017 SEGG. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Effects of Growth Hormone Administration on Muscle Strength in Men over 50 Years Old

    Directory of Open Access Journals (Sweden)

    A. B. W. Tavares

    2013-01-01

    Full Text Available Growth hormone (GH use has been speculated to improve physical capacity in subjects without GH deficiency (GHD through stimulation of collagen synthesis in the tendon and skeletal muscle, which leads to better exercise training and increased muscle strength. In this context, the use of GH in healthy elderly should be an option for increasing muscle strength. Our aim was to evaluate the effect of GH therapy on muscle strength in healthy men over 50 years old. Fourteen healthy men aged 50–70 years were evaluated at baseline for body composition and muscle strength (evaluated by leg press and bench press exercises, which focus primarily on quadriceps—lower body part and pectoralis major—upper body part—muscles, resp.. Subjects were randomised into 2 groups: GH therapy (7 subjects and placebo (7 subjects and reevaluated after 6 months of therapy. Thirteen subjects completed the study (6 subjects in the placebo group and 7 subjects in the GH group. Subjects of both groups were not different at baseline. After 6 months of therapy, muscle strength in the bench press responsive muscles did not increase in both groups and showed a statistically significant increase in the leg press responsive muscles in the GH group. Our study demonstrated an increase in muscle strength in the lower body part after GH therapy in healthy men. This finding must be considered and tested in frail older populations, whose physical incapacity is primarily caused by proximal muscle weakness. The trial was registered with NCT01853566.

  18. Hospitalization of people 50 years old or older living with HIV/AIDS.

    Science.gov (United States)

    Pio, Daiana Patrícia Marchetti; Reinato, Lilian Andreia Fleck; Lopes, Letícia Pimenta; Caliari, Juliano de Souza; Gir, Elucir

    2017-01-01

    Identify the rate and predictive factors of the hospitalization of people living with HIV/AIDS (PLHA), aged 50 years or older. A quantitative, cross-sectional study was conducted at two inpatient units specialized in infectious diseases in a teaching hospital. Data were gathered through individual interviews between August 2011 and February 2015. All ethical precepts were followed. Of the 532 admitted patients, 95 were PLHA 50 years old or older; 30.5% were admitted 3 to 4 times after being diagnosed with HIV/AIDS. Rate of hospitalization was 17.8%, and being 50 to 60 years old was a protective factor against hospitalization. Identificar a taxa e os fatores preditores para a hospitalização de pessoas vivendo com HIV/Aids (PVHA), com idade igual ou superior a 50 anos. Estudo quantitativo, transversal, realizado em duas unidades de internação especializadas em cuidados às doenças infecciosas, de um hospital universitário. A coleta de dados foi realizada por meio de entrevista individual, no período de agosto de 2011 a fevereiro de 2015. Todos os preceitos éticos foram contemplados. Das 532 internações, 95 eram de PVHA com idade igual ou superior a 50 anos; 56,8% receberam o diagnóstico de HIV/Aids antes de terem completado 50 anos de idade; 30,5% foram hospitalizadas de 3 a 4 vezes após o diagnóstico da infecção pelo HIV/Aids. A taxa de hospitalização foi de 17,8%, e a faixa etária de 50 a 60 anos foi fator de proteção para a hospitalização.

  19. Production of fuel chips in a 50-year old Norway spruce stand

    Energy Technology Data Exchange (ETDEWEB)

    Suadicani, K. [Danish Centre for Forest, Landscape and Planning, Hoersholm (Denmark)

    2003-07-01

    The terrain-chipping system is widely used for thinning young stands in Denmark. The system is also relevant in older stands, but problems have occurred when handling larger trees in an upright position. The possibilities of harvesting roundwood and fuel-chips simultaneously (integrated harvesting) have been demonstrated. The felling operation is critical because it determines the chipping productivity and the damage to the remaining trees. The aim of the study was to analyse and compare three whole-tree chipping systems and one integrated harvesting system in a 50-year old stand of Norway spruce. The whole-tree systems had different felling operations: (1) Motor-manual felling, (2) felling and bunching at the striproads (feller-buncher), (3) felling in a herringbone pattern (single-grip harvester). Felling in the integrated harvesting system (4) was also in a herringbone pattern using a single-grip harvester, but the felling included production of a sawlog from the butt-end when possible. All chipping was performed in the stand. It was found that chipping productivity was strongly dependent on ease of feeding the trees into the chipper. Motor-manual felling was cheaper than mechanical felling and bunching, but the bunching improved the chipping productivity so much that it made up for the extra felling costs. Integrated harvesting improved the income, but the net income was lower than for whole-tree chipping with motormanual felling or felling and bunching. It was concluded that easy feeding is essential for chipping productivity and system economy. An alternative could be to use a combined harvester/forwarder for integrated harvesting. (Author)

  20. Multiorgan involvements of cowden disease in 50-year-old woman: A case report and literature overview

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Jae; Jung, Won Sang; Ko, Jeong Min; Park, Hyun Jin [Dept. of Radiology, St. Vincent' s Hospital, The Catholic University of Korea College of Medicine, Suwon (Korea, Republic of)

    2013-09-15

    Cowden disease is the prototype of phosphate and, tensin homologue deleted on the chromosome 10 (PTEN) hamartoma tumor syndrome caused by germline mutations in the tumor suppressor PTEN, which is characterized by multiple developmentally disorganized benign growths, hamartomas, with an increased risk of both benign and malignant tumors. We present another case of Cowden disease in a 50-year-old woman. Besides the diagnostic criteria of Cowden disease, she had various manifestations in thyroid, lung, spleen, liver, pancreas, and muscle. As far as we know, it is the first case showing radiographic findings of hamartomatous lesions in thyroid, spleen, and pancreas, associated with Cowden disease.

  1. Exogenous ochronosis after prolonged use of topical hydroquinone (2% in a 50-year-old Indian female

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    Vijay Gandhi

    2012-01-01

    Full Text Available Ochronosis is a rare disease characterized by speckled and diffuse pigmentation symmetrically over the face, neck, and photo-exposed areas. It is characterized histologically by banana-shaped ochre-colored deposits in the dermis. It can present in exogenous or endogenous form. We report a case of exogenous ochronosis in a 50-year-old Indian woman after prolonged use of topical hydroquinone which is a rare complication with a commonly used drug which is available over the counter.

  2. Effect of adapted karate training on quality of life and body balance in 50-year-old men

    Science.gov (United States)

    Marie-Ludivine, Chateau-Degat; Papouin, Gérard; Saint-Val, Philippe; Lopez, Antonio

    2010-01-01

    Background Aging is associated with a decrease in physical skills, sometimes accompanied by a change in quality of life (QOL). Long-term martial arts practice has been proposed as an avenue to counter these deleterious effects. The general purpose of this pilot study was to identify the effects of an adapted karate training program on QOL, depression, and motor skills in 50-year-old men. Methods and design Fifteen 50-year-old men were enrolled in a one-year prospective experiment. Participants practiced adapted karate training for 90 minutes three times a week. Testing sessions, involving completion of the MOS 36-item Short Form Health Survey (SF36) and Beck Depression Inventory, as well as motor and effort evaluation, were done at baseline, and six and 12 months. Results Compared with baseline, participants had better Beck Depression Inventory scores after one year of karate training (P karate practice had favorable effects on mood, perception of physical health confirmed by better postural control, and improved performance on objective physical testing. Adapted karate training would be an interesting option for maintaining physical activity in aging. PMID:24198552

  3. Size of coarse woody debris 5 years after girdling and removal treatments in 50-year-old Loblolly PIne Plantations

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, M. Boyd [USDA Forest Service, Savannah River, New Ellenton, SC (United States)

    2004-01-01

    PP 108 -113 in: Connor, Kristina F., ed. 2004. Proceedings of the 12th biennial southern silvicultural research conference. Gen. Tech. Rep. SRS71. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station. 594 p. Abstract: In 1996, a study began at Savannah River Site to investigate large-scale replicated forest areas to control coarse woody debris for integrated biodiversity objectives. Research design was a randomized complete block with four treatments replicated in four blocks, resulting in 16 plots. The treatments applied to 50-year-old loblolly pine stands were (1) control, (2) girdling of 25 percent of trees to create catastrophic simulation, (3) annual removal of down woody debris > 10 cm in diameter, and (4) annual removal of both standing and down woody debris > 10 cm in diameter. The study tracks coarse woody debris recruitment and loading, rates of decomposition, and effects on the forest ecosystem.

  4. Effect of adapted karate training on quality of life and body balance in 50-year-old men

    Directory of Open Access Journals (Sweden)

    Marie-Ludivine Chateau-Degat

    2010-08-01

    Full Text Available Marie-Ludivine Chateau-Degat1, Gérard Papouin2, Philippe Saint-Val3, Antonio Lopez21Axe sante des populations et environmentale, CHUQ, Laval University, Quebec, Canada; 2Service de Cardiologie, Centre Hospitalier Territorial du Taone, 3Fédération Tahitienne de Karaté, Papeete, French PolynesiaBackground: Aging is associated with a decrease in physical skills, sometimes accompanied by a change in quality of life (QOL. Long-term martial arts practice has been proposed as an avenue to counter these deleterious effects. The general purpose of this pilot study was to identify the effects of an adapted karate training program on QOL, depression, and motor skills in 50-year-old men.Methods and design: Fifteen 50-year-old men were enrolled in a one-year prospective experiment. Participants practiced adapted karate training for 90 minutes three times a week. Testing sessions, involving completion of the MOS 36-item Short Form Health Survey (SF36 and Beck Depression Inventory, as well as motor and effort evaluation, were done at baseline, and six and 12 months.Results: Compared with baseline, participants had better Beck Depression Inventory scores after one year of karate training (P < 0.01 and better perception of their physical health (P < 0.01, but not on the mental dimension (P < 0.49. They also improved their reaction time scores for the nondominant hand and sway parameters in the eyes-closed position (P < 0.01.Conclusion: Regular long-term karate practice had favorable effects on mood, perception of physical health confirmed by better postural control, and improved performance on objective physical testing. Adapted karate training would be an interesting option for maintaining physical activity in aging.Keywords: karate, balance, training, sport, aging

  5. Live birth in a 50-year-old woman following in vitro fertilization-embryo transfer with autologous oocytes: a rare case report.

    Science.gov (United States)

    Rani, Geetha; Goswami, Sourendra; Chattopadhyay, Ratna; Ghosh, Sanghamitra; Chakravarty, Baidyanath; Ganesh, Ashalatha

    2015-02-01

    To report a live birth with in vitro fertilization (IVF) from a 50-year-old woman with homologous oocytes. Case report. Referral center. A 50-year-old woman. IVF with fresh embryo transfer (ET). Live birth after IVF. A 50-year-old woman conceived with her own oocytes by means of IVF. Three fresh embryos were transferred, resulting in a pregnancy and delivery by cesarean section at 35 weeks of a healthy male baby weighing 2,300 g. Extensive literature search suggests that this is the first case report of live birth in a 50-year-old woman after IVF-ET with her own oocytes. This is a very rare and unusual case that deviates from the norm and therefore warrants attention. In selected cases, assisted reproductive technology might be reasonable to try for a limited number of times with a woman's own oocytes. Copyright © 2015. Published by Elsevier Inc.

  6. Some risk factors for periodontal bone loss in 50-year-old individuals. A 10-year cohort study.

    Science.gov (United States)

    Paulander, Jörgen; Wennström, Jan L; Axelsson, Per; Lindhe, Jan

    2004-07-01

    The aim of this 10-year prospective study of 50-year-old individuals was to analyze the incidence of periodontal bone loss and potential risk factors for periodontal bone loss. The subject sample was generated from an epidemiological survey performed in 1988 of subjects living in the County of Värmland, Sweden. A randomized sample of 15% of the 50-year-old inhabitants in the county was drawn. At the 10-year follow-up in 1998, 320 (75%) of the 449 individuals examined at baseline were available for re-examination, out of which 4 had become edentulous. Full-mouth clinical and radiographic examinations and questionnaire surveys were performed in 1988 and 1998. Two hundred and ninety-five individuals (69%) had complete data for inclusion in the analysis of radiographic bone changes over 10 years. Non-parametric tests, correlations and stepwise multiple regression models were used for statistical analysis of the data. The mean alveolar bone level (ABL) in 1988 was 2.2 mm (0.05) and a further 0.4 mm (0.57) (p=0.000) was lost over the 10 years. Eight percent of the subject sample showed no loss, while 5% experienced a mean bone loss of >/=1 mm. Smoking was found to be the strongest individual risk predictor (RR=3.2; 95% CI 2.03-5.15). When including as smokers only those individuals who had continued with the habit during the entire 10-year follow-up period, the relative risk was slightly increased (3.6; 95% CI 2.32-5.57). Subjects who had quit smoking before the baseline examination did not demonstrate a significantly increased risk for disease progression (RR=1.3; 95% CI 0.57-2.96). Stepwise multiple regression analysis revealed that smoking, % approximal sites with probing pocket depth >/=4 mm, number of teeth and systemic disease were significant explanatory factors for 10-year ABL loss (R(2)=0.12). For never smokers, statistically significant predictors were number of teeth, mean ABL, % periodontally healthy approximal sites and educational level (R(2)=0.20). The

  7. Atomic and nano-scale characterization of a 50-year-old hydrated C3S paste

    KAUST Repository

    Geng, Guoqing

    2015-07-15

    This paper investigates the atomic and nano-scale structures of a 50-year-old hydrated alite paste. Imaged by TEM, the outer product C-S-H fibers are composed of particles that are 1.5-2 nm thick and several tens of nanometers long. 29Si NMR shows 47.9% Q1 and 52.1% Q2, with a mean SiO4 tetrahedron chain length (MCL) of 4.18, indicating a limited degree of polymerization after 50 years\\' hydration. A Scanning Transmission X-ray Microscopy (STXM) study was conducted on this late-age paste and a 1.5 year old hydrated C3S solution. Near Edge X-ray Absorption Fine Structure (NEXAFS) at Ca L3,2-edge indicates that Ca2 + in C-S-H is in an irregular symmetric coordination, which agrees more with the atomic structure of tobermorite than that of jennite. At Si K-edge, multi-scattering phenomenon is sensitive to the degree of polymerization, which has the potential to unveil the structure of the SiO44 - tetrahedron chain. © 2015 Elsevier Ltd. All rights reserved.

  8. Seasonal incidence of medically attended respiratory syncytial virus infection in a community cohort of adults ≥50 years old.

    Directory of Open Access Journals (Sweden)

    David L McClure

    Full Text Available BACKGROUND: Diagnostic testing for respiratory syncytial virus (RSV is not routinely performed in adults. We estimated medically attended RSV seasonal incidence in a community cohort of adults ≥50 years old during four influenza seasons (2006-07 through 2009-10. METHODS: Patients seeking care for acute respiratory illness (ARI were prospectively enrolled and tested for RSV by multiplex RT-PCR. Results from enrolled patients were used to estimate projected cases among non-enrolled patients with ARI. The seasonal incidence of medically attended RSV was the sum of actual and projected cases divided by the community cohort denominator. Since each enrollment period did not include the entire RSV season, incidence estimates were adjusted to account for the statewide proportion of RSV occurring outside the study enrollment period. RESULTS: There were 16,088 to 17,694 adults in the cohort each season and 164 RSV cases in all 4 seasons. The overall seasonal incidence of medically attended RSV was 154 episodes (95% CI, 132-180 per 10,000 persons; the incidence was highest in 2007-08 (179 and lowest in 2006-07 (110. Among persons 50-59, 60-69, and ≥70 years old, RSV incidence was 124 (95% CI, 99-156, 147 (95% CI, 110-196, and 199 (95% CI, 153-258, respectively. CONCLUSIONS: The incidence of medically attended RSV increased with age and was similar during four seasons.

  9. Patient perspectives on online health information and communication with doctors: a qualitative study of patients 50 years old and over.

    Science.gov (United States)

    Silver, Michelle Pannor

    2015-01-13

    As health care systems around the world shift toward models that emphasize self-care management, there is increasing pressure for patients to obtain health information online. It is critical that patients are able to identify potential problems with using the Internet to diagnose and treat a health issue and that they feel comfortable communicating with their doctor about the health information they acquire from the Internet. Our aim was to examine patient-identified (1) problems with using the Internet to identify and treat a health issue, (2) barriers to communication with a doctor about online health information seeking, and (3) facilitators of communication with a doctor about patient searches for health information on the Internet. For this qualitative exploratory study, semistructured interviews were conducted with a sample of 56 adults age 50 years old and over. General concerns regarding use of the Internet to diagnose and treat a health issue were examined separately for participants based on whether they had ever discussed health information obtained through the Internet with a doctor. Discussions about barriers to and facilitators of communication about patient searches for health information on the Internet with a doctor were analyzed using thematic analysis. Six higher-level general concerns emerged: (1) limitations in own ability, (2) credibility/limitations of online information, (3) anxiety, (4) time consumption, (5) conflict, and (6) non-physical harm. The most prevalent concern raised by participants who communicated with a doctor about their online health information seeking related to the credibility or limitations in online information. Participants who had never communicated with a doctor about their online health information seeking most commonly reported concerns about non-physical harm. Four barriers to communication emerged: (1) concerns about embarrassment, (2) concerns that the doctor doesn't want to hear about it, (3) belief that there

  10. General relativity 50 years old

    CERN Multimedia

    1966-01-01

    In May 1916, 'The Foundations of General Relativity Theory' by Albert Einstein was published in 'Annalen der Physik'. Fifty years later, this major contribution to scientific thought still has a rather isolated position with respect to the main-stream of scientific theory. (In contrast, the Special Theory of Relativity is one of the cornerstones of sub-nuclear physics.) To mark the anniversary of the publication of Einstein's paper a theoretician from CERN discusses the theory and its present status.

  11. Identification of aged bloodstains through mRNA profiling: Experiments results on selected markers of 30- and 50-year-old samples.

    Science.gov (United States)

    Zhao, Hemiao; Wang, Chong; Yao, Lan; Lin, Qingluan; Xu, XiuLan; Hu, Lan; Li, Wanshui

    2017-03-01

    Remarkable progress has been made in recent years on the research of body fluid identification through messenger RNA(mRNA) profiling. In order to examine the viability of mRNA profiling as a method to identify aged bloodstains, this study tested two groups of bloodstain samples, dated 30 years and 50 years back respectively, on seven blood specific markers, i.e. HBB, HBA, GYPA, CD93, ALAS2, SPTB (91bp and 247bp primers), and PBGD. Test results indicate that HBA and HBB are the most stable markers in aged bloodstains, returning positive results in over 80% of the 50-year-old samples and over 90% of the 30-year-old samples. This finding proves mRNA profiling an effective way of identifying aged bloodstains.

  12. Dairy Intake Enhances Body Weight and Composition Changes during Energy Restriction in 18–50-Year-Old Adults—A Meta-Analysis of Randomized Controlled Trials

    Directory of Open Access Journals (Sweden)

    Welma Stonehouse

    2016-07-01

    Full Text Available Background/Aims: A meta-analysis of randomized controlled trials (RCTs was performed to investigate the effects of dairy food or supplements during energy restriction on body weight and composition in 18–50-year-old. Methods: RCTs ≥ 4 weeks comparing the effect of dairy consumption (whole food or supplements with control diets lower in dairy during energy restriction on body weight, fat and lean mass were identified by searching MEDLINE, EMBASE, Pubmed, Cochrane Central and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP until March 2016. Reports were identified and critically appraised in duplicate. Data were pooled using random-effects meta-analysis. Chi2- and I2-statistics indicated heterogeneity. Dose effect was assessed using meta-regression analysis. GRADE guidelines were used to rate the quality (QR of the evidence considering risk of bias, inconsistency, indirectness, imprecision, publication bias and effect estimates. Results: 27 RCTs were reviewed. Participants consumed between 2 and 4 standard servings/day of dairy food or 20–84 g/day of whey protein compared to low dairy control diets, over a median of 16 weeks. A greater reduction in body weight (−1.16 kg [−1.66, −0.66 kg], p < 0.001, I2 = 11%, QR = high, n = 644 and body fat mass (−1.49 kg [−2.06, −0.92 kg], p < 0.001, I2 = 21%, n = 521, QR = high were found in studies largely including women (90% women. These effects were absent in studies that imposed resistance training (QR = low-moderate. Dairy intake resulted in smaller loss of lean mass (all trials pooled: 0.36 kg [0.01, 0.71 kg], p = 0.04, I2 = 64%, n = 651, QR = moderate. No between study dose-response effects were seen. Conclusions: Increased dairy intake as part of energy restricted diets resulted in greater loss in bodyweight and fat mass while attenuating lean mass loss in 18–50-year-old adults. Further research in males is needed to investigate sex effects.

  13. Vitamin C Status Correlates with Markers of Metabolic and Cognitive Health in 50-Year-Olds: Findings of the CHALICE Cohort Study

    Science.gov (United States)

    Pearson, John F.; Pullar, Juliet M.; Wilson, Renee; Spittlehouse, Janet K.; Vissers, Margreet C. M.; Skidmore, Paula M. L.; Willis, Jinny; Cameron, Vicky A.; Carr, Anitra C.

    2017-01-01

    A cohort of 50-year-olds from Canterbury, New Zealand (N = 404), representative of midlife adults, undertook comprehensive health and dietary assessments. Fasting plasma vitamin C concentrations (N = 369) and dietary vitamin C intake (N = 250) were determined. The mean plasma vitamin C concentration was 44.2 µmol/L (95% CI 42.4, 46.0); 62% of the cohort had inadequate plasma vitamin C concentrations (i.e., C (i.e., C concentrations indicating deficiency (i.e., C concentration than women, and a higher percentage of vitamin C inadequacy and deficiency. A higher prevalence of hypovitaminosis C and deficiency was observed in those of lower socio-economic status and in current smokers. Adults with higher vitamin C levels exhibited lower weight, BMI and waist circumference, and better measures of metabolic health, including HbA1c, insulin and triglycerides, all risk factors for type 2 diabetes. Lower levels of mild cognitive impairment were observed in those with the highest plasma vitamin C concentrations. Plasma vitamin C showed a stronger correlation with markers of metabolic health and cognitive impairment than dietary vitamin C. PMID:28771190

  14. Vitamin C Status Correlates with Markers of Metabolic and Cognitive Health in 50-Year-Olds: Findings of the CHALICE Cohort Study

    Directory of Open Access Journals (Sweden)

    John F. Pearson

    2017-08-01

    Full Text Available A cohort of 50-year-olds from Canterbury, New Zealand (N = 404, representative of midlife adults, undertook comprehensive health and dietary assessments. Fasting plasma vitamin C concentrations (N = 369 and dietary vitamin C intake (N = 250 were determined. The mean plasma vitamin C concentration was 44.2 µmol/L (95% CI 42.4, 46.0; 62% of the cohort had inadequate plasma vitamin C concentrations (i.e., <50 µmol/L, 13% of the cohort had hypovitaminosis C (i.e., <23 µmol/L, and 2.4% had plasma vitamin C concentrations indicating deficiency (i.e., <11 µmol/L. Men had a lower mean plasma vitamin C concentration than women, and a higher percentage of vitamin C inadequacy and deficiency. A higher prevalence of hypovitaminosis C and deficiency was observed in those of lower socio-economic status and in current smokers. Adults with higher vitamin C levels exhibited lower weight, BMI and waist circumference, and better measures of metabolic health, including HbA1c, insulin and triglycerides, all risk factors for type 2 diabetes. Lower levels of mild cognitive impairment were observed in those with the highest plasma vitamin C concentrations. Plasma vitamin C showed a stronger correlation with markers of metabolic health and cognitive impairment than dietary vitamin C.

  15. Non-contrast-enhanced whole-body magnetic resonance imaging in the general population: the incidence of abnormal findings in patients 50 years old and younger compared to older subjects.

    Directory of Open Access Journals (Sweden)

    Andrzej Cieszanowski

    Full Text Available PURPOSE: To assess and compare the incidence of abnormal findings detected during non-contrast-enhanced whole-body magnetic resonance imaging (WB-MRI in the general population in two age groups: (1 50 years old and younger; and (2 over 50 years old. MATERIALS AND METHODS: The analysis included 666 non-contrast-enhanced WB-MRIs performed on a 1.5-T scanner between December 2009 and June 2013 in a private hospital in 451 patients 50 years old and younger and 215 patients over 50 years old. The following images were obtained: T2-STIR (whole body-coronal plane, T2-STIR (whole spine-sagittal, T2-TSE with fat-saturation (neck and trunk-axial, T2-FLAIR (head-axial, 3D T1-GRE (thorax-coronal, axial, T2-TSE (abdomen-axial, chemical shift (abdomen-axial. Detected abnormalities were classified as: insignificant (type I, potentially significant, requiring medical attention (type II, significant, requiring treatment (type III. RESULTS: There were 3375 incidental findings depicted in 659 (98.9% subjects: 2997 type I lesions (88.8%, 363 type II lesions (10.8% and 15 type III lesions (0.4%, including malignant or possibly malignant lesions in seven subjects. The most differences in the prevalence of abnormalities on WB-MRI between patients 50 years old and younger and over 50 years old concerned: brain infarction (22.2%, 45.0% respectively, thyroid cysts/nodules (8.7%, 18.8%, pulmonary nodules (5.0%, 16.2%, significant degenerative disease of the spine (23.3%, 44.5%, extra-spinal degenerative disease (22.4%, 61.1%, hepatic steatosis (15.8%, 24.9%, liver cysts/hemangiomas (24%, 34.5%, renal cysts (16.9%, 40.6%, prostate enlargement (5.1% of males, 34.2% of males, uterine fibroids (16.3% of females, 37.9% of females. CONCLUSIONS: Incidental findings were detected in almost all of the subjects. WB-MRI demonstrated that the prevalence of the vast majority of abnormalities increases with age.

  16. Non-Contrast-Enhanced Whole-Body Magnetic Resonance Imaging in the General Population: The Incidence of Abnormal Findings in Patients 50 Years Old and Younger Compared to Older Subjects

    Science.gov (United States)

    Cieszanowski, Andrzej; Maj, Edyta; Kulisiewicz, Piotr; Grudzinski, Ireneusz P.; Jakoniuk-Glodala, Karolina; Chlipala-Nitek, Irena; Kaczynski, Bartosz; Rowinski, Olgierd

    2014-01-01

    Purpose To assess and compare the incidence of abnormal findings detected during non-contrast-enhanced whole-body magnetic resonance imaging (WB-MRI) in the general population in two age groups: (1) 50 years old and younger; and (2) over 50 years old. Materials and Methods The analysis included 666 non-contrast-enhanced WB-MRIs performed on a 1.5-T scanner between December 2009 and June 2013 in a private hospital in 451 patients 50 years old and younger and 215 patients over 50 years old. The following images were obtained: T2-STIR (whole body-coronal plane), T2-STIR (whole spine-sagittal), T2-TSE with fat-saturation (neck and trunk-axial), T2-FLAIR (head-axial), 3D T1-GRE (thorax-coronal, axial), T2-TSE (abdomen-axial), chemical shift (abdomen-axial). Detected abnormalities were classified as: insignificant (type I), potentially significant, requiring medical attention (type II), significant, requiring treatment (type III). Results There were 3375 incidental findings depicted in 659 (98.9%) subjects: 2997 type I lesions (88.8%), 363 type II lesions (10.8%) and 15 type III lesions (0.4%), including malignant or possibly malignant lesions in seven subjects. The most differences in the prevalence of abnormalities on WB-MRI between patients 50 years old and younger and over 50 years old concerned: brain infarction (22.2%, 45.0% respectively), thyroid cysts/nodules (8.7%, 18.8%), pulmonary nodules (5.0%, 16.2%), significant degenerative disease of the spine (23.3%, 44.5%), extra-spinal degenerative disease (22.4%, 61.1%), hepatic steatosis (15.8%, 24.9%), liver cysts/hemangiomas (24%, 34.5%), renal cysts (16.9%, 40.6%), prostate enlargement (5.1% of males, 34.2% of males), uterine fibroids (16.3% of females, 37.9% of females). Conclusions Incidental findings were detected in almost all of the subjects. WB-MRI demonstrated that the prevalence of the vast majority of abnormalities increases with age. PMID:25259581

  17. Variables of impact on quality of life of HIV-positive people over 50 years old / Variáveis de impacto na qualidade de vida de pessoas acima de 50 anos HIV+

    Directory of Open Access Journals (Sweden)

    Josevânia da Silva

    2010-01-01

    Full Text Available This study aimed to analyze the influence of biodemographic and clinical variables on quality of life of HIV-positive people over 50 years old. For that, 43 HIV-positive people over 50 took part in the study ( M=55; DP =4.6, being 63% male. The Scale of Quality of Life in Old Age (WHOQOL-OLD and a biodemographic questionnaire were used as instruments. It was verified the impact of biodemographic and clinical variables in the following factors: "Autonomy", "Past, Present and Future Activities", "Death and Dying" and "Intimacy". The QL presented itself as a dimension of human life which is inseparable from objective conditions such as work, leisure, and housing, among others. Moreover, it is related to subjective characteristics, specific to each individual, such as social support.

  18. Characteristics of HIV infections among over 50-year-olds population in China%我国50岁及以上艾滋病病毒感染者/艾滋病患者特征分析

    Institute of Scientific and Technical Information of China (English)

    王丽艳; 秦倩倩; 葛琳; 丁正伟; 蔡畅; 郭巍; 崔岩

    2016-01-01

    目的 分析中国50岁及以上艾滋病病毒感染者/艾滋病患者(HIV/AIDS)人口学、行为学和时空分布特征.方法 通过全国艾滋病综合防治信息系统收集并分析我国50岁及以上HIV/AIDS人口学、行为学和首次CD4+T淋巴细胞(CD4)检测信息,并根据CD4计数水平推算这些病例可能感染时间和感染年龄.结果 2008年以来,我国每年新发现的50岁及以上HIV/AIDS病例数逐年上升,2014年报告50岁及以上病例数是2008年的4.2倍,以异性性传播为主(占88.0%).其中,83.9%自述有非婚异性性接触史,该比例逐年上升.其中男性病例以非婚异性传播为主(占95.1%),女性病例经非婚异性传播和配偶间传播分别占53.4%和46.6%.根据首次CD4检测结果推测病例感染与发现时间间隔,估计近3年感染者比例为15.5%,从感染到被发现时间间隔在8年以上者比例为43.6%.新发现的年龄50岁及以上病例中,约有66.5%的病例可能是在50岁及以后感染,从感染到被检测发现的平均时间为(6.8±2.7)年.结论 50岁及以上HIV/AIDS病例数的增加是该年龄段高危行为暴露和既往感染晚期发现共同作用的结果,需以诊断病例为线索进一步开展溯源和专题调查,排查与控制影响该年龄段艾滋病流行的主要因素.%Objective To analyze the characteristics on demographical,spatial distribution and transmission mode of HIV infections among 50-year-old population.Methods Related information on demography,spatial distribution,high risk behavioral and history of HIV infections among 50-year-old population were collected and analyzed.Possible time of infection based on their first CD4 testing results right after the HIV diagnoses,was estimated.Results Since 2008,the number of new HIV/AIDS cases among the over-50-year-olds was reported increasing annually.The number of aged 50 and above in 2014 was 4.2 times than the number in 2008.50-year-old or older population were

  19. Variáveis de impacto na qualidade de vida de pessoas acima de 50 anos HIV+ Variables of impact on quality of life of HIV-positive people over 50 years old

    Directory of Open Access Journals (Sweden)

    Josevânia da Silva

    2010-04-01

    Full Text Available Este estudo objetivou analisar a influência de variáveis bio-demográficas e clínicas na qualidade de vida (QV de pessoas acima de 50 anos HIV+. Para tanto, contou-se com a participação de 43 pessoas HIV+ acima de 50 anos ( M=55; DP =4,6, sendo 63% do sexo masculino. Utilizou-se como instrumentos a Escala de Qualidade de Vida para a Velhice (WHOQOL-Old e um questionário bio-demográfico. Verificou-se o impacto de variáveis bio-demográficas e clínicas nos seguintes fatores: "Autonomia", "Atividades passadas, presentes e futuras", "Morte e Morrer" e "Intimidade". A QV apresentou-se como uma dimensão da vida humana indissociável de condições objetivas como trabalho, lazer, moradia, dentre outros. Além disso, esse construto está relacionado a características subjetivas, próprias de cada indivíduo, como o suporte social.This study aimed to analyze the influence of biodemographic and clinical variables on quality of life of HIV-positive people over 50 years old. For that, 43 HIV-positive people over 50 took part in the study ( M=55; DP =4.6, being 63% male. The Scale of Quality of Life in Old Age (WHOQOL-OLD and a biodemographic questionnaire were used as instruments. It was verified the impact of biodemographic and clinical variables in the following factors: "Autonomy", "Past, Present and Future Activities", "Death and Dying" and "Intimacy". The QL presented itself as a dimension of human life which is inseparable from objective conditions such as work, leisure, and housing, among others. Moreover, it is related to subjective characteristics, specific to each individual, such as social support.

  20. Achados de retossigmoidoscopias no rastreamento de câncer colorretal em pacientes assintomáticos acima de 50 anos Rectosigmoidoscopy for colorectal câncer screening in asymptomtic 50-year-old

    Directory of Open Access Journals (Sweden)

    Carolina Vannucci V. Nogueira Diogenes

    2007-12-01

    Full Text Available OBJETIVO: Analisar os achados do exame de retossigmoidoscopia no rastreamento de câncer colorretal em pacientes assintomáticos acima de 50 anos. MÉTODOS: Análise prospectiva de 208 pacientes assintomáticos acima de 50 anos e sem história familiar para câncer colorretal, que realizaram retossigmoidoscopia para rastreamento desta neoplasia durante o período de Janeiro de 2005 a Maio de 2006. Dos pacientes analisados, 64,5% eram mulheres e a média de idade era de 60,24 anos (50-91 anos. RESULTADOS: Observamos que 4,8% dos pacientes (n=10 apresentaram pólipos que variavam de 3 a 20mm de tamanho. Todos os pólipos foram retirados e enviados para estudo anatomopatológico. Destes, 3,36% (n=7 foram hiperplásicos e 1,50% (n=3 eram adenomas, sendo dois adenoma tubular com atipias leves e um adenoma com atipias moderadas. Dos dez doentes que tinham pólipos ao exame, nove foram submetidos a videocolonoscopia e um abandonou o acompanhamento. Destes nove, sete pacientes apresentaram ausência de pólipos ao exame colonoscópico, e um apresentou dois pólipos adenomatosos em cólon direito. CONCLUSÕES: A retossigmoidoscopia é um exame acessível na maioria dos serviços que permite identificar pólipos potencialmente neoplásicos em pacientes assintomáticos.ABSTRACT PURPOSE: Analyze the findings of rigid retossigmoidoscopy in asymptomatic patients above 50 years old. METHOD: Prospective analysis of 208 asymptomatic patients above 50 years and without familiar history of colorectal cancer which were submitted to rigid retossigmoidoscopy for colorectal cancer screening on a period of 14 months. RESULTS: 4.8% of the studied patients had polyps which size varied from 3mm to 20mm. All polyps were removed and submitted to pathological examination, where 3.36% (n=7 were hyperplastic polyps and 1.50%(n=3 were adenomas. The patients with polyps on sigmoidoscopic exam then were submitted to videocolonoscopic investigation; of these, seven patients had no

  1. HIV and people over 50 years old in Europe

    DEFF Research Database (Denmark)

    Lazarus, Jeff; Nielsen, K K

    2010-01-01

    The aim of the study was to report on HIV and older people in the European Region, including new data stratified by subregion and year.......The aim of the study was to report on HIV and older people in the European Region, including new data stratified by subregion and year....

  2. TRISOMY 18 in a 50-year-old female

    Directory of Open Access Journals (Sweden)

    Bhanumathi B

    2006-01-01

    Full Text Available She was brought to our Institute at the age of 31, with speech delay and mental handicap. She was assessed by the multidisciplinary team in the institute to determine the cause of her problems. Clinical evaluation revealed dysmorphic facial features, microbrachycephaly, camptodactyly, clinodactyly, abnormal dermatoglyphics and severe mental handicap. Cardiovascular system examination was normal. Chromosomal analysis revealed a trisomy of Chromosome 18. The phenotype of trisomy 18 and the rarity of prolonged survival in this case are discussed.

  3. [The World Health Organization is 50 years old].

    Science.gov (United States)

    1998-10-01

    In celebration of the World Health Organization's 50th anniversary, this article features WHO's contribution to the world by examining its current activities in the areas of health, human rights, and development. It briefly summarizes events leading to its establishment over the period from 1851 to 1948, which marks the year when WHO assumed its role as a specialized body of the United Nations. Quoting from various articles in WHO's Constitution, it illustrates the principles that prompt its actions and that have led nations to become aware of their potential goals, thus steering them toward a brighter future. A brief overview of the last 20 years ends with the introduction of WHO's new Director General, Dr. Gro Harlem Brundtland.

  4. 柳州市1999-2010年50岁以上人群艾滋病流行特点分析%Analysis on the epidemiological characteristics of the over 50 years old HIV/AIDS people in Liuzhou city from 1999 to 2010

    Institute of Scientific and Technical Information of China (English)

    白玉; 梁庆香; 黄宝杨

    2012-01-01

    Objective The study described in this paper was designed to have a better understanding of the epidemic characteristics of the over 50 years old HIV/AIDS people in Liuzhou city so as to provide scientific evidence for the government to establish the prevention and care measures. Method The data including the reports on over 50 years old HIV/AIDS cases in Liuzhou from 1999 to 2010, surveillance, and special surveys were collected and analyzed. Results The cumulative number of HIV/AIDS positive cases reported was 1 788, incuding 977 AIDS patients and 608 deaths. Of all, 1 367 cases were male,421 cases were female, the ratio of gender was 3.25:1,the average age was (61.61±8.01), 50.78% was peasants, and 73.43% was lower than junior high school level. The infection route was 75.84% heterosexual transmission. The trend through heterosexual transmission went up from 1999 to 2010, and the HIV prevalence had climbed to 96.94%. With the in crease in ART treatment the survival time for the 50 years old HIV/AIDS people was prolonged, but only 3.34% was longer than 3 years, still shorter than the average of the general population( 12.29%). This phenomenon might due to the fact that they were not promptly diagnosed when they were infected, thus caused the delay of treatment. Conclusions HIV/AIDS spread rapidly among the over 50 years old people, and the prevention and control of AIDS was very difficult. Therefore effective prevention and control measure should be implemented as soon as possible.%目的 分析柳州市1999-2010年50岁以上人群艾滋病流行特点,为今后制定艾滋病防治措施提供科学依据.方法 收集和分析柳州市1999-2010年50岁以上人群艾滋病疫情报告、综合监测和专项调查资料.结果 1999-2010年累计报告50岁以上人群HIV感染者/AIDS病人1 788人,其中AIDS 977人,死亡608人;男1 367例,女421例,男女性别比为3.25∶1;职业以农民为主,占50.78%;文化程度初中以下的占73.43%;传播

  5. Biological Bases for Radiation Adaptive Responses in the Lung

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Bobby R. [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Lin, Yong [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Wilder, Julie [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States); Belinsky, Steven [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States)

    2015-03-01

    Our main research objective was to determine the biological bases for low-dose, radiation-induced adaptive responses in the lung and use the knowledge gained to produce an improved risk model for radiation-induced lung cancer that accounts for activated natural protection, genetic influences, and the role of epigenetic regulation (epiregulation). Currently, low-dose radiation risk assessment is based on the linear-no-threshold hypothesis which now is known to be unsupported by a large volume of data.

  6. 重庆市50岁及以上城乡居民高血压患病特点及影响因素分析%Analysis on prevalence of hypertension and its associated factors among residents over 50 years old in Chongqing City

    Institute of Scientific and Technical Information of China (English)

    漆莉; 丁贤彬; 毛德强; 冯连贵; 吕晓燕; 焦艳; 张春华; 李洪

    2012-01-01

    Objective To understand the prevalence of hypertension and its associated factors among residents over 50 years old in Chongqing and provide the scientific evidence for non-communicable disease prevention and control. Methods 2 240 residents over 50 years old were sampled by multi-stage stratified random sampling. They were interviewed by face-to-face with questionnaire and physical examination. The influencing factors were identified by multivariate Logistic regression analysis model respectively. Results The prevalence was 50. 4% (the age-adjusted prevalence was 50. 1% ) , it was significantly different between rural and urban. The prevalence among west area of Chongqing was significantly higher than east area and main city of Chongqing, which were 61.4% , 48.1% and 44.5% respectively. The prevalence increased by age. The prevalence of female was higher than that of male, but there was only significant difference a-mong rural. Family history of hypertension was also a risk factor of hypertension. Multivariate Logistic regression analysis results showed that age, low intake of bean produce, family history of hypertension, lack of physical exercise and body mass index (BMI) were independent risk factors of urbanian; age, male, low-level education, high intake of pickle, family history of hypertension, smoking and BMI were independent risk factors of rural population. Conclusions The prevalence of hypertension over 50 years old was high. Age, family history of hypertension and BMI were same risk factors among urban and rural in Chongqing. Among urban, lack of physical exercise and low intake of bean produce were risk factors, while smoking, low-level education and intake of pickle were risk factors among rural. It is urgent to enhance health education , change unhealthy lifestyle and decrease risk factors of hypertension in Chongqing.%目的 了解重庆市50岁及以上城乡居民高血压患病特点及影响因素,为制定防治策略提供科学依据.方法

  7. Correlation analysis of prostate volume with body mass index, blood pressure, blood lipid and glucose in 30-50 year-old men%30~50岁男性前列腺体积与体重指数、血压、血脂及血糖的相关性分析

    Institute of Scientific and Technical Information of China (English)

    王义; 贺利军; 周哲; 赵文峰; 那彦群

    2011-01-01

    Objective:To study the correlation between prostate volume and body mass index, blood pressure, blood lipid and glucose in 30-50 year-old males. Methods: Prostate volume (PV) , body mass index (BMI), blood pressure(BP), blood glucose(BG), blood cholesterol (CHOL), triglyceride (TG), low density lipoprotein (LDL) and high density lipoprotein (HDL) were measured in 1 002 30 50 year-old males. The correlation of PV with BMI, BP, BG, CHOL, TG, LDL, and HDL were analyzed with SPSS 13.0 statistical software. Results: The subjects' average age was (43.66 ± 0.17) years, and their mean prostate volume ( 14.28 ± 0.02 ) mL. The statistical analyses regarding the age (P=0.000,r=0.62), BMI (P=0.013,r=0.57), BG (P=0.032, r=0.52), CHOL (P=0.040,r =0.51 ) , LDL (P =0.032, r= -0.50) , HDL (P =0.017 ,r= -0.48) were significantly associated with PV. Adjusted for age factors, PV still had a strong correlation with BMI and LDL, P values were 0.029, 0.001, r values were 0.53, -0.49. Conclusion: In the 30 - 50 year-old males, BMI and dyslipidemia could be risk factors in the way of the enlarement of prostate volume. Weight control and therapy of blood lipid abnormalities may delay the increase of prostate volume.%目的:了解30~50岁男性前列腺体积与体重指数、血压、血脂及血糖的相关性.方法:从石景山区社会保险中心登记信息中随机抽取1 010名30~50岁男性作为研究对象,行体格检查并计算体重指数(body mass index,BMI),经腹B超测定并计算前列腺体积(prostate volume,PV);空腹抽血检测血糖(blood glucose,BG)、血胆固醇(blood cholesterol,CHOL)、甘油三酯(triglyceride,TG)、低密度脂蛋白(low density lipoprotein,LDL)、高密度脂蛋白(high density lipoprotein,HDL)等,测量血压(blood pressure,BP),应用SPSS13.0统计软件对PV和BMI、BP、BG、CHOL、TG、LDL、HDL的相关性进行统计学分析.结果:符合标准并资料全面者1002人,前列腺体积与年龄、BMI、BG、CHOL、LDL、HDL等

  8. 西部四地50岁以上农村人口年龄相关性白内障手术状况调查%Screening of cataract surgery in four rural populations aged 50 years old and above in western China

    Institute of Scientific and Technical Information of China (English)

    鲍永珍; 曹晓光; 黎晓新; 陈捷; 胡建信; 朱彤

    2009-01-01

    目的 调查我国西部省份青海、云南、贵州和广西50岁及以上农村人口的白内障手术率、手术覆盖率和术后效果.方法 以自然村为抽样单位采用整群抽样方法 抽取年龄≥50岁的农业人口共5562人(青海平安1486人;云南楚雄1494人;贵州六盘水1238人;广西崇左1344人),进行系统的眼科检查和问卷调查.以较好视力眼低于0.1的白内障患者为纳入标准计算白内障手术覆盖率,同时计算白内障手术率(CSR)并分析术后效果.结果 青海平安的白内障手术覆盖率最高为54%,其他3个地区分别为41%、36%和39%;贵州和广西的男性白内障手术覆盖率明显高于女性,青海和云南的白内障手术覆盖率的性别差异无统计学意义.2000-2002年期间青海平安的CSR值最高为1551,其他3个地区的CSR值均在800以下.4个不同人群白内障手术眼的总体人工晶体植入率51.5%,术后视力低于0.1者为40.5%,术后并发症发生率28%.结论 我国西部地区50岁以上人群的白内障手术覆盖率和CSR值较低,同时,术后视力不良的情况较严重.提示在积极增加白内障手术数量的同时,应不断提高白内障手术质量.%Objective To estimate the cataract surgical coverage and cataract surgery rate and to assess the visual outcome of cataract surgery among individuals aged at or over 50 years old in four rural populations from four different areas of western China. Methods This crnss-sectional study, performed during the period 2003-2005, used the method of cluster sampling and recruited 5562 persons aged 50 years old or above through household census. Standardized ocular examinations including visual acuity test, intraocular pressure measurement, slit-lamp and fundus examination were performed. The main outcome criteria were cataract surgical coverage, cataract surgery rate, complication rate and visual outcome after cataract surgery. Results Of individuals whit bilateral presenting visual

  9. New method of techno-economic analysis of radiation impact for nuclear industry

    CERN Document Server

    Chudy, Michal; Müller, Marietta; Slabber, Johan F M

    2016-01-01

    Bearing in mind physical and social aspects, health issues connected with operation of nuclear facilities are under continuous control of national and international regulatory institutions. The main purpose of doing so is to reduce risk of ionizing radiation on human health. Under standard operation of any controlled nuclear facility, direct injuries connected by nonstochastic effects of ionizing radiation, such as Acute Radiation Syndrome (ARS) are theoretically possible only if health and safety measures are violated. On the other hand, the stochastic effect of radiation may cause tumors with increasing probability of received radioactive dose. Nuclear facilities such as nuclear power plants use certain formulas to calculate the cost of potential health damage caused by ionizing radiation. These formulas are derived according to Linear No-Threshold Relationship between the dose and cancer risk. However, this Linear No-Threshold relationship (LNT) is becoming debatable with new radiological research. Therefo...

  10. Experimental Study on the Effects of Yoga Excises on the Physical Function and Mental Health of 35~50 Year-old Women%瑜伽习练对35~50岁女性身体机能与心理健康水平影响的实验研究

    Institute of Scientific and Technical Information of China (English)

    张丽华; 徐新红; 徐细根

    2011-01-01

    探讨瑜伽习练对35~50岁女性身体机能与心理健康水平的影响,研究得出:1.瑜伽习练能显著地改善35~50岁女性的身体形态与机能;2.实验后实验组心理健康总分和各因子得分有了不同程度的下降,与对照组相比,躯体化、强迫症状、抑郁、焦虑和心理健康总分具有显著差异,说明瑜伽习练有效显著地提高35~50岁女性心理健康的水平(P〈0.01).3.时间具有主效应,习练周期的长短对35~50岁女性的心理健康存在显著性影响,对于瑜伽习练的女性来说,必须长期坚持,养成习惯,使瑜伽习练的健康效益长期发挥作用.%This paper discusses on the physical function and mental health effects of the 35~50 year-old female yoga practitioners.The results are: 1.Yoga excises can significantly improve women' body shape and function;2.For the experimental group,the total score and mental health scores had decreased to some degree.Compared with the control,compulsive symptoms,depression,anxiety and mental health scores were significantly different,indicating a significant improvement of physical function and mental health of Yoga practitioners(P0.01).3.Time is the main effect,excise cycle length on the psychological health of women 35~50 years of age had significant effects,for yoga practitioners of women,must be maintained over a long habit,so that the health benefits of yoga practitioners long-term role to play.

  11. Prevalencia de ceguera y limitación visual severa, en personas mayores de 50 años de Ciudad de La Habana Prevalence of blindness and severe visual shortage in over 50 years-old adults in the City of Havana province

    Directory of Open Access Journals (Sweden)

    Abel Cabrera Martínez

    2007-12-01

    Full Text Available Se realizó un estudio descriptivo de corte transversal, cuyo universo estuvo constituido por la población mayor de 50 años perteneciente a Ciudad de La Habana, en el período comprendido entre junio de 2004 a junio del 2005. Para la determinación del tamaño de la muestra se asumió como universo los 633 396 habitantes mayores de 50 años de Ciudad Habana, con una estimación de la prevalencia esperada de 4,0 %, un error aceptable del 3 % y un efecto de diseño de 70 %. Se efectuó un muestreo sistemático por conglomerados y se determinó como muestra 2 760 habitantes de Ciudad de La Habana, representada por 46 cluster de 60 individuos cada uno. Se definió como ceguera la agudeza visual con corrección, inferior a 20/400 y la deficiencia visual grave como la agudeza visual con corrección >20/400 y The universe of a cross-sectional descriptive study, which was carried out from June 2004 to June 2005, was made up of people aged over 50 years, who lived in the City of Havana. In order to determine the sample size, 633 396 over 50 years-old inhabitants were taken as the universe of study, with an expected prevalence estimation of 4.0 %, an allowable error of 3 % and a design effect of 70 %. On the basis of these data, systematic cluster sampling was made to determine a sample of 2 760 inhabitants from the City of Havana, represented by 46 clusters of 60 subjects each. Blindness was defined as corrected visual acuity lower than 20/400 and severe visual shortage as corrected visual acuity >20/400 and <20/200 in the best eye and with the best available correction. An inter-observer variation to reduce errors for this reason was also made. The study coverage was 98.4 % of the selected sample. The blindness prevalence by sex was 2.4 %. Prevalence of bilateral blind persons by age increases from 2.6 % at 50 years to 15,2 % at 80 years and over. The most important causes of bilateral blindness were cataract (50 %, glaucoma (26 % and diabetic

  12. 成都地区30~50岁环卫和白领女性妇科疾病发病状况调查%Investigation of Gynecological Disease for 30~50 Years Old Sanitation and White-collar Females in Chengdu

    Institute of Scientific and Technical Information of China (English)

    袁春梅; 王玲; 张红; 王巧蓉

    2014-01-01

    Objective To know the health status of women of sanitation workers and white-collars in Chengdu,and to ana-lyze the difference between two groups in order to providing the basis data for health education and preventing the Gynecological diseases.Methods The medical examination of gynecological diseases for sanitation women and white-collars women whose age is 30~50 lompere the incidence of the two groups.Results Top four gynecological diseases in the study are chronic cervicitis, uter-ine myoma, ascites and Annex anomaly.The morbidity of chronic cervicitis in sanitation women is significant higher than white-collars women.But,the morbidity of uterine myoma in white-collars women is significantly higher than in sanitation women.In sani-tation women and white-collars women, the morbidities of chronic cervicitis in 30~40 group are significantly higher than 40~50 group; however, the morbidities of uterine myoma, ascites in 40 ~ 50 group are significantly higher than 30 ~ 40 group.Conclusion For 30~40 year old women, chronic cervicitis is the prevention focus, but, uterine myoma is more important in 40~50 year old women.The health education should be given and health examination should be encouraged for women.These methods could raise health awareness of sanitation women, improve the sports consciousness of white-collar women, to prevent or reduce the morbidities of Gynecological diseases.%目的了解成都地区环卫和白领女性妇科疾病的患病状况及原因,为开展健康教育及妇科疾病的防治提供依据。方法对30~50岁的环卫和白领女性进行妇科疾病检测,比较两组的发病情况。结果成都30~50岁环卫和白领女性中妇科疾病前四位分别是慢性宫颈炎、子宫肌瘤、盆腔积液及附件异常。环卫女工慢性宫颈炎的发病率显著高于白领女性,而白领女性子宫肌瘤的发病率显著高于环卫女性,P<0.05;两组内30~40岁组慢性宫颈炎的发病率高于40~50岁组(P<0.05),而40

  13. Pessoas acima de 50 anos com aids: implicações para o dia-a-dia Personas con más de 50 años que tienen sida: implicaciones para el cotidiano People with more than 50 years old with aids: implications to everyday life

    Directory of Open Access Journals (Sweden)

    Soraia Romera Machiesqui

    2010-12-01

    vida.It is a qualitative research that aimed to describe the implications related to everyday life of people with more than 50 years old who acquired immunodeficiency syndrome. It was carried out at a training hospital in the southern Brazil. The data were generated by a dynamic technique using the creativity and sensibility dynamic Speaker Map, with five participants in the group. The data were submitted to a content thematic analysis. From ar tistic productions and reports, emerged the effects from diagnosis discovered; the comprehension that they have a normal life in spite of disease; the faith in God; the prejudice and discrimination; and the silence about the serologic condition. We concluded that the care actions must consider the biological, clinical, social and subjective dimensions in a co-responsibility way in the perspective to their autonomy to health care and to choices of their life.

  14. Vanguards of Paradigm Shift in Radiation Biology: Radiation-Induced Adaptive and Bystander Responses

    OpenAIRE

    MATSUMOTO, Hideki; Hamada, Nobuyuki; Takahashi, Akihisa; Kobayashi, Yasuhiko; Ohnishi, Takeo

    2007-01-01

    The risks of exposure to low dose ionizing radiation (below 100 mSv) are estimated by extrapolating from data obtained after exposure to high dose radiation, using a linear no-threshold model (LNT model). However, the validity of using this dose-response model is controversial because evidence accumulated over the past decade has indicated that living organisms, including humans, respond differently to low dose/low dose-rate radiation than they do to high dose/high dose-rate radiation. In oth...

  15. Changing Attitude Toward Radiation Carcinogenesis and Prospects for Novel Low-Dose Radiation Treatments.

    Science.gov (United States)

    Socol, Yehoshua; Welsh, James S

    2016-12-01

    All procedures involving ionizing radiation, whether diagnostic or therapeutic, are subject to strict regulation, and public concerns have been raised about even the low levels of radiation exposures involved in diagnostic imaging. During the last 2 decades, there are signs of more balanced attitude to ionizing radiation hazards, as opposed to the historical "radiophobia." The linear no-threshold hypothesis, based on the assumption that every radiation dose increment constitutes increased cancer risk for humans, is increasingly debated. In particular, the recent memorandum of the International Commission on Radiological Protection admits that the linear no-threshold hypothesis predictions at low doses (that International Commission on Radiological Protection itself has used and continues to use) are "speculative, unproven, undetectable, and 'phantom'." Moreover, numerous experimental, ecological, and epidemiological studies suggest that low doses of ionizing radiation may actually be beneficial to human health. Although these advances in scientific understanding have not yet yielded significant changes in radiation regulation and policy, we are hopeful such changes may happen in the relatively near future. This article reviews the present status of the low-dose radiation hazard debate and outlines potential opportunities in the field of low-dose radiation therapy. © The Author(s) 2015.

  16. The demoiselle of X-inactivation: 50 years old and as trendy and mesmerising as ever.

    Directory of Open Access Journals (Sweden)

    Céline Morey

    2011-07-01

    Full Text Available In humans, sexual dimorphism is associated with the presence of two X chromosomes in the female, whereas males possess only one X and a small and largely degenerate Y chromosome. How do men cope with having only a single X chromosome given that virtually all other chromosomal monosomies are lethal? Ironically, or even typically many might say, women and more generally female mammals contribute most to the job by shutting down one of their two X chromosomes at random. This phenomenon, called X-inactivation, was originally described some 50 years ago by Mary Lyon and has captivated an increasing number of scientists ever since. The fascination arose in part from the realisation that the inactive X corresponded to a dense heterochromatin mass called the "Barr body" whose number varied with the number of Xs within the nucleus and from the many intellectual questions that this raised: How does the cell count the X chromosomes in the nucleus and inactivate all Xs except one? What kind of molecular mechanisms are able to trigger such a profound, chromosome-wide metamorphosis? When is X-inactivation initiated? How is it transmitted to daughter cells and how is it reset during gametogenesis? This review retraces some of the crucial findings, which have led to our current understanding of a biological process that was initially considered as an exception completely distinct from conventional regulatory systems but is now viewed as a paradigm "par excellence" for epigenetic regulation.

  17. Cross-national differences in grip strength among 50+ year old Europeans

    DEFF Research Database (Denmark)

    Andersen-Ranberg, Karen; Petersen, Inge; Frederiksen, Henrik;

    2009-01-01

    , education, health and socioeconomic status. The relative excess was found to be 11% and the absolute difference 5.0 kg for 50- to 54-year-old men, increasing to 28% and 6.9 kg among 80+ year-old men. The corresponding figures for women were 16% and 4.3 kg, and 21% and 3.5 kg, respectively. Southern European...... with higher rates of functional decline and mortality, and thus may be used as a health indicator, it is of interest to examine whether the results on extremely old can be reproduced in a large-scale European survey. GS was measured in a cross-sectional population-based sample of 27,456 individuals aged 50...

  18. Illegal drugs laws: clearing a 50-year-old obstacle to research.

    Directory of Open Access Journals (Sweden)

    David Nutt

    2015-01-01

    Full Text Available The United Nations drug control conventions of 1960 and 1971 and later additions have inadvertently resulted in perhaps the greatest restrictions of medical and life sciences research. These conventions now need to be revised to allow neuroscience to progress unimpeded and to assist in the innovation of treatments for brain disorders. In the meantime, local changes, such as the United Kingdom moving cannabis from Schedule 1 to Schedule 2, should be implemented to allow medical research to develop appropriately.

  19. [Criterion and Construct Validity in Nursing Diagnosis "Sedentary Lifestyle" in People over 50 Years Old].

    Science.gov (United States)

    Guirao-Goris, Silamani J; Ferrer Ferrandis, Esperanza; Montejano Lozoya, Raimunda

    2016-02-18

    The aim of the study is to identify the construct and criterion validity of the nursing diagnosis label Sedentary Lifestyle. A cross-sectional study in a nursing consultation in primary health care was conducted. Participants were all people that was attended for one year over 50 who voluntarily wish to participate (n=85) in the study. Objective weekly physical activity was measured in METs with an Accelerometer, objective measure of performance was measured by gait speed EPESE Battery (both measures that were used as the gold standard), and physical activity questionnaires (RAPA), the COOP-WONCA physical fitness chart. Spearman correlation coefficients, mean comparison tests and analysis of sensitivity and specificity were used as statistical analysis. The diagnosis "Sedentary Lifestyle" showed a positive correlation between its manifestations and physical activity measured in METs (r=0.39) and EPESE gait speed (r=0.35). The diagnosis showed a sensitivity of 85.1% and a specificity of 65.2% and showed ability to discriminate active people from those that are not using METs as a measure of physical activity (t=-4.4). The diagnosis "Sedentary Lifestyle" shows criterion and construct validity.

  20. Aryabhatta Research Institute of Observational Sciences: reincarnation of a 50 year old State Observatory of Nainital

    Science.gov (United States)

    Sagar, Ram

    2006-03-01

    The fifty year old State Observatory, well known as U.P. State Observatory till the formation of Uttaranchal in November 2000, was reincarnated on March 22, 2004 as Aryabhatta Research Institute of Observational Sciences with acronym ARIES, an autonomous institute, under the Department of Science & Technology, Government of India. The growth of academic and technical activities and new mandate of the Institute are briefly described. In early 60's, the Institute was one of the 12 centres established by the Smithsonian Astrophysical Observatory, USA, all over the globe but the only centre in India for imaging artificial earth satellites. Commensurating with its observing capabilities, the Institute started a number of front-line research programmes during the last decade, e.g., optical follow up observations of GRB afterglows, radio and space borne astronomical resources, intra-night optical variability in active galactic nuclei as well as gravitational microlensing and milli-magnitude variations in the rapidly oscillating peculiar A type stars. As a part of atmospheric studies, characterisation of aerosol at an altitude of about 2 km is going on since 2002. ARIES has plans for establishing modern observing facilities equipped with latest backend instruments in the area of both astrophysics and atmospheric science. Formation of ARIES, therefore augurs well for the overall development of astrophysics and atmospheric science in India.

  1. Behavior, knowledge and perception of risks about sexually transmitted diseases in a group of people over 50 years old Comportamiento, conocimiento y percepción de riesgo sobre enfermedades sexualmente transmisibles en un grupo de personas con 50 o más años de edad Comportamento, conhecimento e percepção de risco sobre doenças sexualmente transmissíveis em um grupo de pessoas com 50 anos e mais de idade

    Directory of Open Access Journals (Sweden)

    Magali Olivi

    2008-08-01

    Full Text Available The goal was to analyze the behavior, knowledge and risk perception about sexually transmitted diseases / AIDS (STD/AIDS in people over 50 years old. 165 public servants at a State Secretary in Mato Grosso, Brazil were interviewed. The chi-square test and logistic regression tests were used for the analysis of risk perception and the behavior and knowledge variables about STD/AIDS. Most of the respondents were female (60.6%, 63.2 had a fixed partner, 72.4% had sexual relations in the past six months, and only 13.3% always wore condoms, with 21.5% being male and 8% female. Perception of risk was associated with non-use of condoms in their last sexual relation (pEl objetivo fue analizar aspectos de comportamiento, conocimiento y percepción de riesgo de las ETS/SIDA, en personas con 50 o más años de edad. Se entrevistaron 165 servidores de una Secretaría del estado de Mato Groso, Brasil. Se utilizó una prueba de Chi cuadrado y de regresión logística para analizar la percepción de riesgo y las variables de comportamiento y conocimiento sobre las ETS/SIDA. La mayoría de los entrevistados era del sexo femenino (60,6%; para el comportamiento un 63,2 % tenía pareja fija y un 72,4 % tuvo relación sexual en los últimos 6 meses; apenas el 13,3 % utiliza siempre preservativo, el 21,5 % de los hombres y el 8 % de las mujeres. Se demostró que existe una asociación entre la percepción de riesgo y el uso de preservativo en la última relación sexual (p Objetivou-se analisar o comportamento, conhecimento e percepção de risco às doenças sexualmente transmissíveis/AIDS (DST/AIDS em pessoas com 50 anos e mais de idade. Foram entrevistados 165 servidores de uma secretaria estadual de Mato Grosso, Brasil. Utilizou-se o teste de qui-quadrado e regressão logística para análise da percepção do risco e variáveis do comportamento e conhecimento sobre DST/AIDS. A maioria dos entrevistados é do sexo feminino (60,6%, 63,2% tem parceiro fixo e 72

  2. Donor-specific cell-based assays in studying sensitivity to low-dose radiation: a population-based perspective

    Directory of Open Access Journals (Sweden)

    Dora eIl'yasova

    2014-11-01

    Full Text Available Currently, a linear no-threshold model is used to estimate health risks associated with exposure to low-dose radiation, a prevalent exposure in the general population, because the direct estimation from epidemiological studies suffers from uncertainty. This model has been criticized based on unique biology of low-dose radiation. Whether the departure from linearity is toward increased or decreased risk is intensely debated. We present an approach based on individual radiosensitivity testing and discuss how individual radiosensitivity can be assessed with the goal to develop a quantifiable measure of cellular response that can be conducted via high-throughput population testing.

  3. Cancer Mortality Among People Living in Areas With Various Levels of Natural Background Radiation

    Directory of Open Access Journals (Sweden)

    Ludwik Dobrzyński

    2015-07-01

    Full Text Available There are many places on the earth, where natural background radiation exposures are elevated significantly above about 2.5 mSv/year. The studies of health effects on populations living in such places are crucially important for understanding the impact of low doses of ionizing radiation. This article critically reviews some recent representative literature that addresses the likelihood of radiation-induced cancer and early childhood death in regions with high natural background radiation. The comparative and Bayesian analysis of the published data shows that the linear no-threshold hypothesis does not likely explain the results of these recent studies, whereas they favor the model of threshold or hormesis. Neither cancers nor early childhood deaths positively correlate with dose rates in regions with elevated natural background radiation.

  4. Proposed Radiation Guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Davey, C. S.

    2004-07-01

    Current scientific evidence is that radiation at low levels is not harmful, but beneficial. This is borne out by both radiobiology and epidemiology. The ICRP 26 recommended limits of 50 mSv and 5 mSv per annum are comparable with the average natural background levels in Iran and Norway, respectively, and levels five times higher than that quoted for Iran are to be found in some populated parts of this world. The new limits proposed for ionising radiation are generated by comparison to existing recommended limits for essential minerals. There is a range of acceptable exposures to radiation, just as there is for minerals. The replacement for the ICRP 60 recommendations (20 mSv and 1 mSv for radiation workers and public respectively) should be higher limits of 200 mSv and 50 mSv. There should also be minimum recommended annual levels of 10 mSv, for both radiation workers and the public. The consequences of not proposing this change are continuing huge negative impacts to society. In cancer therapy, even the older guidelines caused unnecessary expense and delays. The cost to Canada is astronomical, when one considers the effect of the existing limits on the use of nuclear power, and the resulting use of hydrocarbons and the consequent increase in acid rain, etc. Of course, the same thing can be said of the entire world limited funds are diverted from areas where they would be better applied, and alternative solutions to societal needs are implemented, solutions which increase pollution and cause injury and death. It is time to reverse the current, expensive trend into misapplied ALARA, based on the paranoia about all things nuclear, which has developed since the linear no-threshold hypothesis was first proposed.propose the transition to a realistic and balanced approach to ionising radiation. (Author)

  5. Secondary osteoporosis due to radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Katsuyuki; Kihana, Toshimasa; Inoue, Yasuhiro; Takeda, Yasunari; Matsuura, Shumpei; Kataoka, Masaaki; Hamamoto, Ken (Ehime Univ., Shigenobu (Japan). School of Medicine)

    1991-09-01

    Bone mineral density (BMD) of the 3rd lumber vertebra (L3) and the 5th lumber vertebra (L5) were measured by quantitative computed tomography (QCT). BMD of L3 and L5 in 139 normal control cases decreased linearly with age (L3: Y= 317.32 - 3.283X, L5: Y= 314.35 - 2.9056X). Ratio of the BMD of L5 to L3 (L5/L3 ratio, %) was constant in the value of 106.03{+-}12.84% before 50 years old and increased linearly after 50 years old (Y= 21.624 + 1.7187X). In 30 radiated cases, BMD of the radiated L5 ws decreased after 20 Gy of radiation and reached 47.44{+-}18.74% of the preradiated value after 50 Gy of radiation. L5/L3 ratio was also decreased after 20 Gy of radiation and reached 48.34{+-}19.33% of pre-radiated value after 50 Gy radiation. BMD of L5 and L5/L3 ratio after 50 Gy of radiation were decreased linearly with age (L5: Y= 107.44 - 0.9686X, L5/L3 ratio: Y= 106.98 - 0.9472X). Quality of life (performance status: PS, lumbago score) after radiation correlated significantly with age, body weight, BMD of L3 before radiation, BMD of L5 after radiation. PS and lumbago score were increased significantly in cases of more than 75 years old, less than 50 kg, less than 100 mg/cm{sup 3} of BMD of L3 before radiation and less than 40 mg/cm{sup 3} of BMD of L5 after radiation. Quality of life after radiation was improved by treatment of alfacalcidol (PS: 3.0{+-}0.61 to 1.2{+-}0.47, lumbago score: 15.4{+-}4.08 to 4.2{+-}1.17). In conclusion, it should be said that pelvic radiation for gynecologic malignancy may disturb the bone metabolism and quality of life in the early phase after radiation, especially in the aged patients and that quality of life could be improved by treatment of alfacalcidol. (author).

  6. [BARRIERS ASSOCIATED WITH BREAST SELF-EXAMINATION AMONG WOMEN 18 TO 50 YEARS OLD: A CROSS SECTIONAL STUDY].

    Science.gov (United States)

    Martínez Torres, Javier; Pabón-Rozo, César Eduardo; Quintero-Contreras, Natalia; Soto Galván, Jordán; López-Mayorga, Rafael; Rojas-Tinico, Yeinly; Ramírez-Vélez, Robinson

    2015-10-01

    Introducción: el cáncer de mama es la neoplasia maligna más común entre las mujeres y se asocia con altos niveles de morbilidad y mortalidad en países en desarrollo. El autoexamen de mama es un método fundamental de diagnóstico precoz del cáncer mamario. El objetivo de este estudio fue determinar la prevalencia y evaluar las barreras asociadas a la realización del autoexamen de mama, en mujeres de 18 a 50 años. Métodos: estudio descriptivo, transversal, en 627 mujeres sanas entre los 18 y 50 años de edad, de Pamplona, Colombia. Las barreras para la práctica del autoexamen (edad, estado civil, religión, antecedentes familiares y asesoría profesional o medios de comunicación), se recogieron mediante encuesta estructurada. Se calcularon prevalencias de cada factor y se establecieron asociaciones mediante la construcción de modelos de regresión. Resultados: en el momento de la encuesta, cerca del 72 % de las mujeres acusaron no haberse practicado el autoexamen de mama en el último mes, y el 45 % en los últimos seis meses. Los modelos de regresión muestran que las mujeres pertenecientes al grupo etáreo de 30 a 39 años, las que no tuvieron asesoría por parte de un profesional de la salud y quienes no presentaron antecedentes familiar de cáncer de mama; se asociaron como barreras para el auto-examen de mama. Conclusión: la realización del autoexamen de mama en la población estudiada fue baja. Estos datos podrían utilizarse para ofrecer programas de intervención educativa acerca de la importancia del diagnóstico temprano del cáncer de mama.

  7. PREVALENCE AND RISK FACTORS OF PERIPHERAL ARTERIAL DISEASE IN DIABETIC PATIENTS OVER 50 YEARS OLD IN CHINA

    Institute of Scientific and Technical Information of China (English)

    Heng Guan; Zheng-yan Sheng; Hao-ming Tian; Da-long Zhu; De-min Yu; Wei-te Zhuang; Lu-lu Chen; Jian-ping Weng; Yong-jun Li; Zhang-rong Xu; Guang-wei Li; Xiao-hui Guo; Zhi-min Liu; Da-jin Zou; Hui-li Xing; Wei Liu

    2007-01-01

    Objective To investigate the prevalence of peripheral arterial disease (PAD) in China type 2 diabetic patients and to demonstrate the relationships between putative risk factors and PAD.Methods In total 1 397 type 2 diabetic patients aged 50 years and older were enrolled and determined ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) in 15 Class HI Grade A hospitals in 7 major cities of China.Results Mean patient age was 63. 7 ± 8. 2 years and mean duration of diabetes mellitus was 9. 39 ± 7. 4 years. Two hundreds and seventy-two (19. 47% ) patients were diagnosed as PAD by ABI< 0. 9, 122 (18. 37% ) in male and 150 (20. 46% ) in female. PAD patients had a significantly longer duration of diabetes mellitus, higher hemoglobin Ale, and a significantly lower mean body mass index than non-PAD ones. Aging, smoking, and systolic blood pressure were found to be positively related with the prevalence of PAD. In terms of lipid profiles, no variable was found to relate with PAD. Notably, baPWV showed as the same significant guiding index for PAD, almost matched with ABI.Conclusions PAD is a common complication in China type 2 diabetic patients. Therefore, PAD screening and treatment should be emphasized for diabetic patients with high risk factors.

  8. Neurodegenerative changes in the brainstem and olfactory bulb in people older than 50 years old: a descriptive study

    Directory of Open Access Journals (Sweden)

    Francine Hehn de Oliveira

    2015-07-01

    Full Text Available With the increase in life expectancy in Brazil, concerns have grown about the most prevalent diseases in elderly people. Among these diseases are neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. Protein deposits related to the development of these diseases can pre-date the symptomatic phases by years. The tau protein is particularly interesting: it might be found in the brainstem and olfactory bulb long before it reaches the limbic cortex, at which point symptoms occur. Of the 14 brains collected in this study, the tau protein was found in the brainstems of 10 (71.42% and in olfactory bulbs of 3 out 11. Of the 7 individuals who had a final diagnosis of Alzheimer’s disease (AD, 6 presented tau deposits in some region of the brainstem. Our data support the idea of the presence of tau protein in the brainstem and olfactory bulb in the earliest stages of AD.

  9. Unraveling 50-Year-Old Clues Linking Neurodegeneration and Cancer to Cycad Toxins: Are microRNAs Common Mediators?

    Science.gov (United States)

    Spencer, Peter; Fry, Rebecca C; Kisby, Glen E

    2012-01-01

    Recognition of overlapping molecular signaling activated by a chemical trigger of cancer and neurodegeneration is new, but the path to this discovery has been long and potholed. Six conferences (1962-1972) examined the puzzling neurotoxic and carcinogenic properties of a then-novel toxin [cycasin: methylazoxymethanol (MAM)-β-d-glucoside] in cycad plants used traditionally for food and medicine on Guam where a complex neurodegenerative disease plagued the indigenous population. Affected families showed combinations of amyotrophic lateral sclerosis (ALS), parkinsonism (P), and/or a dementia (D) akin to Alzheimer's disease (AD). Modernization saw declining disease rates on Guam and remarkable changes in clinical phenotype (ALS was replaced by P-D and then by D) and in two genetically distinct ALS-PDC-affected populations (Kii-Japan, West Papua-Indonesia) that used cycad seed medicinally. MAM forms DNA lesions - repaired by O(6)-methylguanine methyltransferase (MGMT) - that perturb mouse brain development and induce malignant tumors in peripheral organs. The brains of young adult MGMT-deficient mice given a single dose of MAM show DNA lesion-linked changes in cell-signaling pathways associated with miRNA-1, which is implicated in colon, liver, and prostate cancers, and in neurological disease, notably AD. MAM is metabolized to formaldehyde, a human carcinogen. Formaldehyde-responsive miRNAs predicted to modulate MAM-associated genes in the brains of MGMT-deficient mice include miR-17-5p and miR-18d, which regulate genes involved in tumor suppression, DNA repair, amyloid deposition, and neurotransmission. These findings marry cycad-associated ALS-PDC with colon, liver, and prostate cancer; they also add to evidence linking changes in microRNA status both to ALS, AD, and parkinsonism, and to cancer initiation and progression.

  10. Unraveling 50-year-old clues linking neurodegeneration and cancer to cycad toxins: are microRNAs a common mediator?

    Directory of Open Access Journals (Sweden)

    Peter eSpencer

    2012-09-01

    Full Text Available Recognition of overlapping molecular signaling activated by a chemical trigger of cancer and neurodegeneration is new, but the path to this discovery has been long and potholed. Six conferences (1962-1972 examined the puzzling neurotoxic and carcinogenic properties of a then-novel toxin [cycasin: methylazoxymethanol (MAM-β-D-glucoside] in cycad plants used traditionally for food and medicine on Guam where a complex neurodegenerative disease plagued the indigenous population. Affected families showed combinations of amyotrophic lateral sclerosis (ALS, parkinsonism (P and/or a dementia (D akin to Alzheimer’s disease (AD. Modernization saw declining disease rates on Guam and remarkable changes in clinical phenotype (ALS was replaced by P-D and then by D and in two genetically distinct ALS-PDC-affected populations (Kii-Japan, West Papua-Indonesia that used cycad seed medicinally. MAM forms DNA lesions -- repaired by O6-methylguanine methyltransferase (MGMT -- that perturb mouse brain development and induce malignant tumors in peripheral organs. The brains of young adult MGMT-deficient mice given a single dose of MAM show DNA lesion-linked changes in cell signaling pathways associated with miRNA-1, which is implicated in colon, liver and prostate cancers, and in neurological disease, notably AD. MAM is metabolized to formaldehyde, a human carcinogen. Formaldehyde-responsive miRNAs predicted to modulate MAM-associated genes in the brains of MGMT-deficient mice include miR-17-5p and miR-18d, which regulate genes involved in tumor suppression, DNA repair, amyloid deposition, and neurotransmission. These findings marry cycad-associated ALS-PDC with colon, liver and prostate cancer; they also add to evidence linking changes in microRNA status both to ALS, AD, and parkinsonism, and to cancer initiation and progression.

  11. Growth hormone responses to 3 different exercise bouts in 18- to 25- and 40- to 50-year-old men.

    Science.gov (United States)

    Gilbert, Kate L; Stokes, Keith A; Hall, George M; Thompson, Dylan

    2008-08-01

    Exercise is a potent stimulus for growth hormone (GH) release, although aging appears to attenuate this response. The aim of this study was to investigate GH responses to different exercise stimuli in young and early middle-aged men. Eight men aged 18-25 y and 8 men aged 40-50 y completed 3 trials, at least 7 days apart, in a random order: 30 s cycle-ergometer sprint (sprint), 30 min resistance exercise bout (resistance), 30 min cycle at 70% maximal oxygen consumption (endurance). Blood samples were taken pre-, during, and post-exercise, and area under the GH vs. time curve was calculated for a total of 120 min. Mean blood lactate concentrations and percentage heart rate maximum at which the participants were working were not different between groups in any of the trials. In both groups, blood lactate concentrations were significantly lower in the endurance trial than in the sprint and resistance trials. There were no significant differences in resting GH concentration between groups or trials. GH AUC was significantly greater in the young group than the early middle-aged group, in both sprint (531 (+/-347) vs. 81 (+/-54) microg.L-1 per 120 min, p = 0.003) and endurance trials (842 (+/-616) vs. 177 (+/-137) microg.L-1 per 120 min, p = 0.010). Endurance exercise elicits a greater GH response than sprint and resistance exercise; however, aging per se, factors associated with aging, or an inability to achieve a sufficient absolute exercise intensity results in a smaller GH response to an exercise stimulus in early middle-aged men.

  12. Knowledge, attitudes and behaviours related to dietary sodium among 35- to 50-year-old Ontario residents

    Science.gov (United States)

    Papadakis, Sophia; Pipe, Andrew L; Moroz, Isabella A; Reid, Robert D; Blanchard, Christopher M; Cote, Danielle F; Mark, Amy E

    2010-01-01

    BACKGROUND: Excessive consumption of dietary sodium is an important public health issue. Little is known about the knowledge, attitudes and behaviours related to sodium consumption among Canadians. OBJECTIVE: To examine knowledge, attitudes and behaviours related to sodium consumption among a sample of Canadians 35 to 50 years of age. METHODS: A random-digit-dial telephone survey was conducted among adults aged 35 to 50 years of age in two regions in Ontario. Logistic regression was used to examine the likelihood of having taken action in the past 30 days to reduce sodium consumption, and the likelihood that respondents were intending to reduce sodium in the next six months. RESULTS: A total of 3130 interviews were completed. The majority of respondents were aware of excessive sodium consumption as a health issue and reported that they were taking action to reduce their dietary sodium intake. A large proportion of respondents did not correctly identify many foods as being high in sodium and, consequently, may have incorrectly believed they were consuming healthy amounts of sodium. Respondents who believed sodium reduction was important were more likely to have taken action to reduce sodium within the previous 30 days. Respondents who self-identified as consuming too much sodium were less likely to have taken action. CONCLUSIONS: The findings of the present study suggest that in addition to policy changes designed to reduce the sodium content of foods, there is a need to address the low levels of knowledge surrounding sources of excessive sodium in popular Canadian foods, the importance of a reduced intake of sodium and the availability of lower-sodium alternatives. PMID:20485696

  13. Plenary panel 1: The scientific bases of radiation protection. Non-targeted effects of ionising radiation - Implications for radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Salomaa, S. [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2006-07-01

    The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects, genomic instability and adaptive response. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. New aspects include the role of cellular communication and tissue-level responses. A better understanding of non-targeted effects may have important consequences for health risk assessment and, consequently, on radiation protection. Non-targeted effects may contribute to the estimation of cancer risk from occupational, medical and environmental exposures. In particular, they may have implications for the applicability of the Linear-No-Threshold (L.N.T.) model in extrapolating radiation risk data into the low-dose region. This also means that the adequacy of the concept of dose to estimate risk is challenged by these findings. Moreover, these effects may provide new mechanistic explanations for the development of non-cancer diseases. Further research is required to determine if these effects, typically measured in cell cultures, are applicable in tissue level, whole animals, and ultimately in humans. (authors)

  14. Non-targeted effects of ionising radiation - Implications for radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Sisko Salomaa [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2006-07-01

    The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects, genomic instability and adaptive response. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. New aspects include the role of cellular communication and tissue-level responses. A better understanding of non-targeted effects may have important consequences for health risk assessment and, consequently, on radiation protection. Non-targeted effects may contribute to the estimation of cancer risk from occupational, medical and environmental exposures. In particular, they may have implications for the applicability of the Linear-No-Threshold (LNT) model in extrapolating radiation risk data into the low-dose region. This also means that the adequacy of the concept of dose to estimate risk is challenged by these findings. Moreover, these effects may provide new mechanistic explanations for the development of non-cancer diseases. Further research is required to determine if these effects, typically measured in cell cultures, are applicable in tissue level, whole animals, and ultimately in humans. (author)

  15. Low dose ionizing radiation induced acoustic neuroma: A putative link?

    Directory of Open Access Journals (Sweden)

    Sachin A Borkar

    2012-01-01

    Full Text Available Although exposure to high dose ionizing radiation (following therapeutic radiotherapy has been incriminated in the pathogenesis of many brain tumors, exposure to chronic low dose ionizing radiation has not yet been shown to be associated with tumorigenesis. The authors report a case of a 50-year-old atomic reactor scientist who received a cumulative dose of 78.9 mSv over a 10-year period and was detected to have an acoustic neuroma another 15 years later. Although there is no proof that exposure to ionizing radiation was the cause for the development of the acoustic neuroma, this case highlights the need for extended follow-up periods following exposure to low dose ionizing radiation.

  16. Ultraviolet radiation: questions of hazard, homeostasis, or hormesis?

    Energy Technology Data Exchange (ETDEWEB)

    Sliney, D. [USA Center for Health Promotion and Preventive Medicine, Gunpowder, MD (United States)

    2004-07-01

    The general approach taken when dealing with health issues arising from chronic human exposure to solar ultraviolet radiation appear to be quite different from that taken with the safety of human exposure to ionizing radiation. The public climate for accepting scientific risk assessments of human exposure appears to be markedly different for these two types of radiation exposures. Issues relating to setting exposure guidelines, such as dose response, with arguments over ''linear-no-threshold'' or ''hormesis,'' have engendered much debate and have severely challenged the development of a consensus on how to best control the health hazards from low-level ionizing radiation exposure. By contrast, these same questions are rarely raised in the public policy arena with regard to health policies for dealing with ultraviolet, non-ionizing radiation. Ultraviolet radiation exposure is a known carcinogen, but workers and the general public willingly expose themselves routinely to levels of ultraviolet radiation exceeding health exposure guidelines. Occupational health and safety advisors are constantly challenged on how to cope with exposure of the outdoor worker to the ultraviolet radiation in sunlight that can exceed health guidelines. A de facto consensus that permits workers to be exposed far above guidelines appears to exist because of the overwhelming public acceptance of the concept that ultraviolet radiation in sunlight has some benefit, despite the risk. A similar public perception generally does not exist for ionizing radiation, but are there similar risks? From a biophysical standpoint, the generally accepted target molecule is DNA and the single-hit theory would apply to both. Unlike ionizing radiation the target organs are limited to skin and eye. Furthermore, cancer of the eye in humans is virtually unknown; whereas, cancer of the skin is most common. It would be well to examine whether the potential for different outcomes

  17. The communication of the radiation risk from CT in relation to its clinical benefit in the era of personalized medicine. Pt. 1. The radiation risk from CT

    Energy Technology Data Exchange (ETDEWEB)

    Westra, Sjirk J. [Massachusetts General Hospital, Division of Pediatric Radiology, Boston, MA (United States)

    2014-10-15

    The theory of radiation carcinogenesis has been debated for decades. Most estimates of the radiation risks from CT have been based on extrapolations from the lifespan follow-up study of atomic bomb survivors and on follow-up studies after therapeutic radiation, using the linear no-threshold theory. Based on this, many population-based projections of induction of future cancers by CT have been published that should not be used to estimate the risk to an individual because of their large margin of error. This has changed recently with the publication of three large international cohort follow-up studies, which link observed cancers to CT scans received in childhood. A fourth ongoing multi-country study in Europe is expected to have enough statistical power to address the limitations of the prior studies. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report released in 2013 specifically addresses variability in response of the pediatric population exposed to ionizing radiation. Most authorities now conclude that there is enough evidence to link future cancers to the radiation exposure from a single CT scan in childhood but that cancer risk estimates for individuals must be based on the specifics of exposure, age at exposure and absorbed dose to certain tissues. Generalizations are not appropriate, and the communication of the CT risk to individuals should be conducted within the framework of personalized medicine. (orig.)

  18. Commentary: ethical issues of current health-protection policies on low-dose ionizing radiation.

    Science.gov (United States)

    Socol, Yehoshua; Dobrzyński, Ludwik; Doss, Mohan; Feinendegen, Ludwig E; Janiak, Marek K; Miller, Mark L; Sanders, Charles L; Scott, Bobby R; Ulsh, Brant; Vaiserman, Alexander

    2014-05-01

    The linear no-threshold (LNT) model of ionizing-radiation-induced cancer is based on the assumption that every radiation dose increment constitutes increased cancer risk for humans. The risk is hypothesized to increase linearly as the total dose increases. While this model is the basis for radiation safety regulations, its scientific validity has been questioned and debated for many decades. The recent memorandum of the International Commission on Radiological Protection admits that the LNT-model predictions at low doses are "speculative, unproven, undetectable and 'phantom'." Moreover, numerous experimental, ecological, and epidemiological studies show that low doses of sparsely-ionizing or sparsely-ionizing plus highly-ionizing radiation may be beneficial to human health (hormesis/adaptive response). The present LNT-model-based regulations impose excessive costs on the society. For example, the median-cost medical program is 5000 times more cost-efficient in saving lives than controlling radiation emissions. There are also lives lost: e.g., following Fukushima accident, more than 1000 disaster-related yet non-radiogenic premature deaths were officially registered among the population evacuated due to radiation concerns. Additional negative impacts of LNT-model-inspired radiophobia include: refusal of some patients to undergo potentially life-saving medical imaging; discouragement of the study of low-dose radiation therapies; motivation for radiological terrorism and promotion of nuclear proliferation.

  19. The Genetics Panel of the NAS BEAR I Committee (1956): epistolary evidence suggests self-interest may have prompted an exaggeration of radiation risks that led to the adoption of the LNT cancer risk assessment model.

    Science.gov (United States)

    Calabrese, Edward J

    2014-09-01

    This paper extends a series of historical papers which demonstrated that the linear-no-threshold (LNT) model for cancer risk assessment was founded on ideological-based scientific deceptions by key radiation genetics leaders. Based on an assessment of recently uncovered personal correspondence, it is shown that some members of the United States (US) National Academy of Sciences (NAS) Biological Effects of Atomic Radiation I (BEAR I) Genetics Panel were motivated by self-interest to exaggerate risks to promote their science and personal/professional agenda. Such activities have profound implications for public policy and may have had a significant impact on the adoption of the LNT model for cancer risk assessment.

  20. Health risks associated with low dose diagnostic or therapeutic radiation exposures

    Energy Technology Data Exchange (ETDEWEB)

    Boreham, D.R. [McMaster Univ., Dept. of Medical Physics and Applied Radiation Sciences, Hamilton, Ontario (Canada)

    2007-07-01

    The health risks to humans associated with exposure to low doses of ionizing radiation have been extrapolated from effects observed at high doses, dose rates, and mixed radiation qualities using a linear no threshold model. Based on this approach, it has been argued that human exposure to low doses of diagnostics X-rays and gamma-rays increase an individual's risk of developing cancer throughout their life-time. Also, repeated medical diagnostic procedures involving low dose exposures will have an additive effect and consequently further increase health risk. The specific aim of this seminar will be to address the relative risk associated with diagnostic X-rays from CT scans and gamma-rays from positron emission tomography (PET) scans. Objectives of the talk will include: 1) Defining low dose exposures at a cellular level and relate that to diagnostic or therapeutic exposures, 2) Describing modern tools in molecular cytogenetics to estimate radiation exposure and assess radiation risk, 3) Identifying the different cellular mechanisms that influence radiation risk at high and low dose exposures and relate that to individual radiation risk. (author)

  1. Evidence supporting radiation hormesis in atomic bomb survivor cancer mortality data.

    Science.gov (United States)

    Doss, Mohan

    2012-12-01

    A recent update on the atomic bomb survivor cancer mortality data has concluded that excess relative risk (ERR) for solid cancers increases linearly with dose and that zero dose is the best estimate for the threshold, apparently validating the present use of the linear no threshold (LNT) model for estimating the cancer risk from low dose radiation. A major flaw in the standard ERR formalism for estimating cancer risk from radiation (and other carcinogens) is that it ignores the potential for a large systematic bias in the measured baseline cancer mortality rate, which can have a major effect on the ERR values. Cancer rates are highly variable from year to year and between adjacent regions and so the likelihood of such a bias is high. Calculations show that a correction for such a bias can lower the ERRs in the atomic bomb survivor data to negative values for intermediate doses. This is consistent with the phenomenon of radiation hormesis, providing a rational explanation for the decreased risk of cancer observed at intermediate doses for which there is no explanation based on the LNT model. The recent atomic bomb survivor data provides additional evidence for radiation hormesis in humans.

  2. ATRIAL SEPTAL DEFECT IN A 50 YEARS OLD MALE PRESENTING AS OBLIQUE SEPTAL CANAL THAT APPEARED TO BE REGULATED BY FIVE LUMINAL BANDS

    Directory of Open Access Journals (Sweden)

    Ainory Peter Gesase

    2014-09-01

    Full Text Available To date seven different types of atrial septal defects (ASD have been described and they include septum primum, septum secundum, superior vena cava, inferior vena cava, coronary sinus and patent foramen ovale types of ASD. One feature in common among these ASD’s is that they all present with a hole that may allow communication between the left and right atria. The current observation reports what appears to be a new type of ASD that is characterized by the presence of an oblique septal canal that opens into the right and left atria. The right atrial opening was D-shaped and measured about 0.9 cm wide and the left atrial opening was crescent-shaped and measuring about 0.5 cm wide. In addition to this the left atrial opening was associated with five luminal bands; the last three bands lies on the roof of the oblique septal canal. The action of pulling the first luminal band resulted into closure of the left atrial opening an indication that the bands prevented blood coming from the lungs from entering into the right atrium. The presence of oblique septal canal and luminal bands has not been reported in relation to the ASD’s. Continued documentation of such anomalies remains clinically important particularly in African settings where unexplained illnesses are easily attributed to endemic diseases.

  3. Congenital hip dysplasia treated by total hip arthroplasty using cementless tapered stem in patients younger than 50 years old: results after 12-years follow-up.

    Science.gov (United States)

    Faldini, Cesare; Miscione, Maria Teresa; Chehrassan, Mohammadreza; Acri, Francesco; Pungetti, Camilla; d'Amato, Michele; Luciani, Deianira; Giannini, Sandro

    2011-12-01

    Congenital hip dysplasia may lead to severe acetabular and femoral abnormalities that can make total hip arthroplasty a challenging procedure. We assessed a series of patients affected by developmental hip dysplasia treated with total hip arthroplasty using cementless tapered stem and here we report the outcomes at long-term follow-up. Twenty-eight patients (24 women and 4 men) aged between 44 and 50 years (mean 47 years) were observed. Clinical evaluation was rated with the Harris Hip Score. Radiographic evaluation consisted in standard anteroposterior and axial view radiographs of the hip. According to Crowe's classification, 16 hips presented dysplasia grade 1, 14 grade 2, and 4 grade 3. All patients were treated with total hip arthroplasty using a cementless tapered stem (Wagner Cone Prosthesis). Six patients were operated bilaterally, with a totally of 34 hips operated. After surgery, the patients were clinically and radiographically checked at 3, 6, and 12 months and yearly thereafter until an average follow-up of 12 years (range 10-14 years). Average Harris Hip Score was 56 ± 9 (range 45-69) preoperatively, 90 ± 9 (range 81-100) 12 months after surgery, and 91 ± 8 (range 83-100) at last follow-up. Radiographic evaluation demonstrated excellent osteointegration of the implants. Signs of bone resorption were present in 6 hips, nevertheless no evidence of loosening was observed and none of the implants has been revised. Even in dysplasic femur, the tapered stem allowed adequate stability and orientation of the implant. We consider tapered stem a suitable option for total hip arthroplasty in developmental hip dysplasia, also in case of young patients, thanks to the favourable long-term results.

  4. Synchronous bilateral breast carcinoma in a 50-year-old man with 45,X/46,XY mosaic karyotype: report of a case.

    Science.gov (United States)

    Franceschini, Gianluca; D'Alba, Pierfrancesco; Costantini, Melania; Magistrelli, Andrea; Belli, Paolo; Mulè, Antonino; Coco, Claudio; Picciocchi, Aurelio

    2006-01-01

    We report a case of synchronous bilateral breast cancer in a patient with ambiguous external genitalia attributed to a 45,X/46,XY mosaicism. To our knowledge, this represents the first such case ever to be reported. Mammography, ultrasonography, computed tomography, and magnetic resonance imaging all showed bilateral suspicious breast masses with microcalcifications. There were no radiological findings of muscle invasion or axillary lymphadenopathy. The patient was successfully treated by bilateral radical modified mastectomy followed by external irradiation and adjuvant endocrine therapy. Histological examination revealed a bilateral ductal carcinoma in situ, with a cribriform and papillary pattern and microfoci of infiltrating ductal carcinoma. The hormonal profile revealed high levels of follicle-stimulating hormone and luteinizing hormone, and low levels of testosterone. Testicular sonography revealed small hypoechoic testicles with bilateral microlithiasis. This case shows that 45,X/46,XY men may have an increased risk of breast cancer and must be followed up carefully.

  5. Review on radiation protection in diagnostic radiology

    Directory of Open Access Journals (Sweden)

    Vahid Karami

    2016-10-01

    Full Text Available Discovery of x-ray and using of it for medical imaging have produced tremendous outcomes for diagnosis and treatment of diseases. More than 10 million diagnostic radiological procedures and 100,000 nuclear medicine exams are being performed daily around the world. According to the national commission on radiological protection and measurements (NCRP-report 160, medical x-ray is contribute to approximately 95% of all radiological examinations that is responsible for 74% of the collective dose to the US population. Despite of unique benefits of ionizing radiations, in the field of radiation protection, they are associated with potential risks such as cancer and genetically abnormalities. The cancer risk attributable to diagnostic radiology is estimated about 0.6% to 3%. It is estimated that the radiation dose from diagnostic x-ray procedures are annually responsible for 7,587 and 5,695 cases of radiation induced cancer in the population of Japan and US, respectively. Although the radiation dose associated with most radiological procedures are very low, but rapid increasing use of radiography procedures during two past decades have been concerned due to the cancer risk associated with ionizing radiations. On the base of linear no-threshold (LNT model of dose-response curve, any level of exposure is dangerous. Deoxyribonucleic acid (DNA is the main target of ionizing radiation. For radiological exposure with low dose, the stochastic effects such as genetic damages and leukemia are concerned. According to the recommendations of the radiation protection regulatory organizations, radiological procedure must be done with respect to social and economic factors in which exposure of patient and population kept as low as reasonable and achievable. Hence, prescription of a radiological test is acceptable only when its advantages are higher than its damages. Optimizing the different parameters such as: collimating the primary beam field to the area of

  6. Atomic Bomb Survivors Life-Span Study: Insufficient Statistical Power to Select Radiation Carcinogenesis Model.

    Science.gov (United States)

    Socol, Yehoshua; Dobrzyński, Ludwik

    2015-01-01

    The atomic bomb survivors life-span study (LSS) is often claimed to support the linear no-threshold hypothesis (LNTH) of radiation carcinogenesis. This paper shows that this claim is baseless. The LSS data are equally or better described by an s-shaped dependence on radiation exposure with a threshold of about 0.3 Sievert (Sv) and saturation level at about 1.5 Sv. A Monte-Carlo simulation of possible LSS outcomes demonstrates that, given the weak statistical power, LSS cannot provide support for LNTH. Even if the LNTH is used at low dose and dose rates, its estimation of excess cancer mortality should be communicated as 2.5% per Sv, i.e., an increase of cancer mortality from about 20% spontaneous mortality to about 22.5% per Sv, which is about half of the usually cited value. The impact of the "neutron discrepancy problem" - the apparent difference between the calculated and measured values of neutron flux in Hiroshima - was studied and found to be marginal. Major revision of the radiation risk assessment paradigm is required.

  7. The concept of ''risk'' and its implementation in radiation protection; Der Risikobegriff und seine Umsetzung im Strahlenschutz

    Energy Technology Data Exchange (ETDEWEB)

    Breckow, J. [Fachbereich Mathematik, Naturwissenschaften und Informatik (MNI), Fachhochschule Giessen-Friedberg (Germany)

    2005-07-01

    The principle of risk limitation is one of the main pillars of radiation protection. Based on the linear no threshold (LNT) hypothesis this principle works from the assumption that risks associated with radiation exposure cannot be entirely avoided, but only limited. The risk value to which such risks should be limited cannot be decided solely on the basis of natural science but is rather determined through the mechanisms of a complex societal process. It is not possible to measure or calculate radiation-induced risks directly, especially not risks incurred by individuals. It therefore appears sensible to apply the principle of risk limitation to measurable quantities which are related to the risk, even though they may not be identical with it. Put a little simply, as far as stochastic radiation effects are concerned this is the only legitimate reason for creating and defining quantities of dosage. Seen this way, in radiation protection the principle of risk limitation is implemented via the concept of (individual) dose limitation. The details of how this principle is implemented in radiation protection are more subtle than it might sometimes seem. The present paper takes a closer look at the individual steps involved.

  8. Differential Response and Priming Dose Effect on the Proteome of Human Fibroblast and Stem Cells Induced by Exposure to Low Doses of Ionizing Radiation.

    Science.gov (United States)

    Hauptmann, Monika; Haghdoost, Siamak; Gomolka, Maria; Sarioglu, Hakan; Ueffing, Marius; Dietz, Anne; Kulka, Ulrike; Unger, Kristian; Babini, Gabriele; Harms-Ringdahl, Mats; Ottolenghi, Andrea; Hornhardt, Sabine

    2016-03-01

    It has been suggested that a mechanistic understanding of the cellular responses to low dose and dose rate may be valuable in reducing some of the uncertainties involved in current risk estimates for cancer- and non-cancer-related radiation effects that are inherited in the linear no-threshold hypothesis. In this study, the effects of low-dose radiation on the proteome in both human fibroblasts and stem cells were investigated. Particular emphasis was placed on examining: 1. the dose-response relationships for the differential expression of proteins in the low-dose range (40-140 mGy) of low-linear energy transfer (LET) radiation; and 2. the effect on differential expression of proteins of a priming dose given prior to a challenge dose (adaptive response effects). These studies were performed on cultured human fibroblasts (VH10) and human adipose-derived stem cells (ADSC). The results from the VH10 cell experiments demonstrated that low-doses of low-LET radiation induced unique patterns of differentially expressed proteins for each dose investigated. In addition, a low priming radiation dose significantly changed the protein expression induced by the subsequent challenge exposure. In the ADSC the number of differentially expressed proteins was markedly less compared to VH10 cells, indicating that ADSC differ in their intrinsic response to low doses of radiation. The proteomic results are further discussed in terms of possible pathways influenced by low-dose irradiation.

  9. Low doses of radiation reduce risks in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Mitchel, R.E.J. [Atomic Energy of Canada Ltd., Chalk River, Ontario (Canada)

    2004-05-01

    The 'Linear No Threshold' hypothesis, used in all radiation protection practices, assumes that all doses, no matter how low, increase risk. The protective effects of adaptive responses to radiation, shown to exist in lower organisms and in human and other mammalian cells, are inconsistent with this hypothesis. An in vivo test of the hypothesis in mice showed that a 100-mGy dose of {gamma}-radiation protected the mice by increasing latency for acute myeloid leukemia initiated by a subsequent large dose. A similar result was observed in cancer prone mice, where a 10-mGy adapting exposure prior to a large acute dose increased latency for lymphomas without altering frequency. Increasing the adapting dose to 100-mGy eliminated the protective effect. In the cancer prone mice, a 10-mGy dose alone, without a subsequent high dose, increased latency for spontaneous osteosarcomas and lymphomas without altering frequency. Increasing the dose to 100-mGy decreased latency for spontaneous osteosarcomas but still increased latency for lymphomas, indicating that this higher dose was in a transition zone between reduced and increased risk, and that the transition dose from protective to detrimental effects is tumor type specific. In genetically normal fetal mice, prior low doses also protected against radiation induced teratogenic effects. In genetically normal adult male mice, high doses induce mutations in sperm stem cells, detectable as heritable mutations in the offspring of these mice. A prior 100 mGy dose protected the male mice from induction of these heritable mutations by the large dose. We conclude that adaptive responses are induced by low doses in normal or cancer prone mice, and that these responses can reduce the risk of cancer, teratogenesis and heritable mutations. At low doses in vivo, the relationship between dose and risk is not linear, and low doses can reduce risk. (author)

  10. From 'Image Gently' to image intelligently: a personalized perspective on diagnostic radiation risk

    Energy Technology Data Exchange (ETDEWEB)

    Guillerman, R.P. [Department of Pediatric Radiology, Texas Children' s Hospital, Baylor College of Medicine, Houston, TX (United States)

    2014-10-15

    The risk of ionizing radiation from diagnostic imaging has been a popular topic in the radiology literature and lay press. Communicating the magnitude of risk to patients and caregivers is problematic because of the uncertainty in estimates derived principally from epidemiological studies of large populations, and alternative approaches are needed to provide a scientific basis for personalized risk estimates. The underlying patient disease and life expectancy greatly influence risk projections. Research into the biological mechanisms of radiation-induced DNA damage and repair challenges the linear no-threshold dose-response assumption and reveals that individuals vary in sensitivity to radiation. Studies of decision-making psychology show that individuals are highly susceptible to irrational biases when judging risks. Truly informed medical decision-making that respects patient autonomy requires appropriate framing of radiation risks in perspective with other risks and with the benefits of imaging. To follow the principles of personalized medicine and treat patients according to their specific phenotypic and personality profiles, diagnostic imaging should optimally be tailored not only to patient size, body region and clinical indication, but also to underlying disease conditions, radio-sensitivity and risk perception and preferences that vary among individuals. (orig.)

  11. The evolution of and challenges for industrial radiation processing—2012

    Science.gov (United States)

    Berejka, A. J.; Cleland, M. R.; Walo, M.

    2014-01-01

    The evolution of industrial radiation processing is traced from Roentgen's discovery of X-radiation in 1895 by following the development of high current, electron beam accelerators (EB) throughout the twentieth century. Although Becquerel soon followed Roentgen with his discovery of what became to be known as radioactivity, electrical sources for ionizing radiation dominate industrial processing with there being more than ten times as many industrial installations using high current EB equipment than the facilities relying upon large concentrations of radioactive isotopes. In the 1950s, the discovery that ionizing radiation would enhance the value of what has become the world's largest volume commodity plastic, polyethylene (PE), opened the way for full scale commercial use of high current EB equipment. While the crosslinking of the PE insulation on wire became one of the first major industrial applications, other uses of EB processing soon followed. In the 1970s, low-energy, self-shielded EB equipment made the surface curing of inks, coatings and adhesives more industrially viable. In the early part of the twenty-first century, new market applications involving the low-energy EB surface decontamination of packaging materials emerged. This new area poses challenges for the metrology needed to control industrial processes, in that there is limited EB penetration into what have been used as dosimeters by industry. Major industrial use of radiation process is now over 50 years old. Because of the diversity of end-uses and the fact that the use of ionizing radiation in industry is a process technique, it is hard to quantify the value-added to numerous commercial products that benefit from this energy efficient process. It may be in excess of a trillion Euros in value-added to articles of commerce. In this milieu, there are some broad-based opportunities for research which are noted.

  12. Responses to low doses of ionizing radiation in biological systems.

    Science.gov (United States)

    Feinendegen, Ludwig E; Pollycove, Myron; Sondhaus, Charles A

    2004-07-01

    1 per day for protracted exposure. The balance between damage and protection favors protection at low cell doses and damage at high cell doses. Bystander effects from high-dosed cells to nonirradiated neighboring cells appear to include both damage and protection.Regarding oncogenesis, a model based on the aforementioned dual response pattern at low doses and dose rates is consistant with the nonlinear reponse data and contradicts the linear no-threshold dose-risk hypothesis for radiation-induced cancer. Indeed, a dose-cancer risk function should include both linear and nonlinear terms.

  13. One-year follow-up results of a randomized controlled clinical trial on internet-based cognitive behavioral therapy for subthreshold depres- sion in people over 50 years old.

    NARCIS (Netherlands)

    Spek, V.; Cuijpers, P.; Nyklicek, I.; Smits, N.; Riper, H.; Pop, V.

    2008-01-01

    Background Internet-based cognitive behaviour therapy (CBT) is a promising new approach for the treatment of depressive symptoms. The current study had two aims: (1) to determine whether, after 1 year, an internet-based CBT intervention was more effective than a waiting-list control group; and (2) t

  14. “My body's a 50 year-old but my brain is definitely an 85 year-old”: exploring the experiences of men ageing with HIV-associated neurocognitive challenges

    Directory of Open Access Journals (Sweden)

    Lisa Hopcroft

    2013-07-01

    Full Text Available Introduction: Research investigating HIV, neurocognition and ageing is well developed using neuropsychometric or other quantitative approaches; however, little is known about individuals’ subjective experiences. The purpose of this article is to explore the experiences of men aged 50 and older who self-identify as having HIV-associated neurocognitive challenges. In particular, this study uses the Episodic Disability Framework (EDF to explore participants’ perceptions regarding: 1 symptoms/impairments, difficulties with day-to-day activities, challenges with social inclusion and uncertainty; 2 ageing as related to their HIV-associated neurocognitive challenges, and 3 the episodic nature of their HIV-associated neurocognitive challenges. Methods: This qualitative, interpretive study involved in-depth, semi-structured interviews with 12 men aged 50 years and older who self-identified as having HIV-associated neurocognitive challenges. Participants were recruited from a neurobehavioural research unit (NBRU at a large hospital in Toronto, Canada. Data were analyzed thematically and with reference to the EDF. Results: Participants’ experiences reflected all concepts within the EDF to some extent. Difficulties with daily activities were diverse but were addressed using similar living strategies. Participants described challenges with work and social relationships resulting from neurocognitive challenges. Participants downplayed the significance of uncertainty in their lives, which they attributed to effective living strategies. Most men reported confusion regarding the link between their neurocognitive challenges and ageing. Others discussed ageing as an asset that helped with coping. Conclusions: This is the first study to use a disability framework to examine the subjective experiences of men ageing with HIV-associated neurocognitive challenges. Findings reframe the episodic disability experienced by these individuals as being predictably linked to certain triggers. As such, support for managing neurocognitive challenges could focus on triggers that exacerbate the condition in addition to the impairments themselves. The study also describes ageing as not only a source of problems but also as an asset among men growing older with HIV.

  15. Aged-Related Changes in Body Composition and Association between Body Composition with Bone Mass Density by Body Mass Index in Chinese Han Men over 50-year-old.

    Directory of Open Access Journals (Sweden)

    Ying Jiang

    Full Text Available Aging, body composition, and body mass index (BMI are important factors in bone mineral density (BMD. Although several studies have investigated the various parameters and factors that differentially influence BMD, the results have been inconsistent. Thus, the primary goal of the present study was to further characterize the relationships of aging, body composition parameters, and BMI with BMD in Chinese Han males older than 50 years.The present study was a retrospective analysis of the body composition, BMI, and BMD of 358 Chinese male outpatients between 50 and 89 years of age that were recruited from our hospital between 2009 and 2011. Qualified subjects were stratified according to age and BMI as follows: 50-59 (n = 35, 60-69 (n = 123, 70-79 (n = 93, and 80-89 (n = 107 years of age and low weight (BMI: < 20 kg/m2; n = 21, medium weight (20 ≤ BMI < 24 kg/m2; n = 118, overweight (24 ≤ BMI < 28 kg/m2; n = 178, and obese (BMI ≥ 28 kg/m2; n = 41. Dual-energy X-ray absorptiometry (DEXA was used to assess bone mineral content (BMC, lean mass (LM, fat mass (FM, fat-free mass (FFM, lumbar spine (L1-L4 BMD, femoral neck BMD, and total hip BMD. Additionally, the FM index (FMI; FM/height2, LM index (LMI; LM/height2, FFM index (FFMI; [BMC+LM]/height2, percentage of BMC (%BMC; BMC/[BMC+FM+LM] × 100%, percentage of FM (%FM; FM/[BMC+FM+LM] × 100%, and percentage of LM (%LM; LM/(BMC+FM+LM × 100% were calculated. Osteopenia or osteoporosis was identified using the criteria and T-score of the World Health Organization.Although there were no significant differences in BMI among the age groups, there was a significant decline in height and weight according to age (p < 0.0001 and p = 0.0002, respectively. The LMI and FFMI also declined with age (both p < 0.0001 whereas the FMI exhibited a significant increase that peaked in the 80-89-years group (p = 0.0145. Although the absolute values of BMC and LM declined with age (p = 0.0031 and p < 0.0001, respectively, there was no significant difference in FM. In terms of body composition, there were no significant differences in %BMC but there was an increase in %FM (p < 0.0001 and a decrease in %LM (p < 0.0001 with age. The femoral neck and total hip BMD significantly declined with age (p < 0.0001 and p = 0.0027, respectively but there were no differences in L1-L4. BMD increased at all sites (all p < 0.01 as BMI increased but there were declines in the detection rates of osteoporosis and osteopenia (both p < 0.001. A logistic regression revealed that when the medium weight group was given a BMI value of 1, a decline in BMI was an independent risk factor of osteoporosis or osteopenia, while an increase in BMI was a protective factor for BMD. At the same time, BMD in L1-L4 exhibited a significant positive association with FMI (p = 0.0003 and the femoral neck and total hip BMDs had significant positive associations with FFMI and LMI, respectively (both p < 0.0001.These data indicate that LMI and FFMI exhibited significant negative associations with aging in Chinese Han males older than 50 years, whereas FMI had a positive association. BMD in the femoral neck and total hip declined with age but an increased BMI was protective for BMD. LMI and FFMI were protective for BMD in the femoral neck and total hip.

  16. Evaluation the treatment outcomes of intracapsular femoral neck fractures with closed or open reduction and internal fixation by screw in 18-50-year-old patients in Isfahan from Nov 2010 to Nov 2011

    Directory of Open Access Journals (Sweden)

    Mohammad Javdan

    2013-01-01

    Conclusion: This study showed that femoral neck fracture is associated with several complications, especially if open reduction was necessary. So, the surgical method and necessary equipments such as radiolucent bed, C-ARM machine, and implant cannulated screw set should be considered.

  17. Validez y reproducibilidad de un cuestionario de frecuencia de consumo de calcio para mujeres entre 30 y 50 años: Validation and reproducibility of a calcium frequency of consumption questionnaire for 30 through 50 year-old women

    Directory of Open Access Journals (Sweden)

    Carlos Rojas

    2011-07-01

    Full Text Available Objetivos: Medir la validez y la reproducibilidad de un cuestionario de frecuencia de consumo de alimentos (FCA, para evaluar el consumo de calcio en mujeres. Diseño: Estudio de tipo longitudinal y prospectivo. Lugar: Hogares en la ciudad del Lima, del entorno familiar de los estudiantes de la EAP de Nutrición. Participantes: Mujeres de 30 a 50 años. Métodos: Se capacitó 78 mujeres voluntarias entre 30 y 50 años de edad para llevar un registro de alimentos (REG ingeridos durante 7 días, en dos períodos distintos, con cuatro meses de diferencia entre ambos. En el segundo periodo se les administró una encuesta de FCA con 24 alimentos y preparaciones presentadas en porciones habituales. Para medir la concordancia se calculó la rho de Spearman y el coeficiente kappa; también la sensibilidad y especificidad de la FCA; se elaboró un gráfico de Bland y Altman. Principales medidas de resultados: Miligramos de calcio consumidos, según REG y FCA. Resultados: Los promedios de consumo de calcio durante 14 días en los registros de 24 horas, según FCA1 y el FCA2, fueron 415 mg ± 130,4 mg, 564 mg ± 362,5 y 490 mg ± 338,3 mg, respectivamente. El coeficiente kappa fue 0,247, bajo pero significativo. El 98,7% y 76,9% de las mujeres tuvieron consumo deficiente según los 14 registros y según la FCA, respectivamente. La sensibilidad fue 77,9%, la especificidad 100% y el valor predictivo positivo 100%. Conclusiones: Los coeficientes de asociación encontrados fueron bajos. Sin embargo, debido a la alta incidencia de consumo deficiente de calcio el formato empleado tiene una buena capacidad de detectar a las personas con un consumo deficiente.

  18. 50岁以上精神分裂症患者的认知特征%Clinical analysis of cognitive function in schizophrenic patients with age being more than 50 years old

    Institute of Scientific and Technical Information of China (English)

    左小光; 杨甫德; 吉中孚

    2001-01-01

    Objective:To explore the characteristics and influence factors of cognitive impairment in schizophrenic patients (age≥50y). Method:Sixty schizophrenic patients and 40 normal controls were examined with Wisconsin card sorting test (WCST),Wechsler adult intelligence scale (WAIS-R),Wechsler memory scale (WMS),the language fluency test (LF),the finger tapping test (FTT),the brief psychiatric rating scale (BPRS) and the scale for the assessment of negative symptoms (SANS). Results:The cognitive functions in schizophrenia were reduced more significantly than that in controls.Age,illness duration,negative symptoms and subtype of diagnosis were associated with cognitive deficits in schizophrenia. Conclusion:The senile schizophrenic patients with long duration sever negative symptoms and non-paranoid type may have more obvious cognitive deficits.%目的:探讨50岁以上精神分裂症患者的认知损害特征及其影响因素。方法:对60例50岁以上精神分裂症患者和40例正常人进行了威斯康星卡片分类测验(WCST)、韦氏成人智力量表(WAIS-R)、韦氏记忆量表(WMS)、语言流利性测验(LF)、手指敲击测验(FTT)、简明精神病评定量表(BPRS)及阴性症状评定量表(SANS)等测查。结果:患者组的所有认知测查结果均较正常人显著减退,且年龄、病程,阴性症状及亚型对患者认知功能有显著影响。结论:年龄较大、病程较长、阴性症状较重及非偏执型的精神分裂症患者认知缺损严重。

  19. Aged-Related Changes in Body Composition and Association between Body Composition with Bone Mass Density by Body Mass Index in Chinese Han Men over 50-year-old

    Science.gov (United States)

    Jin, Mengmeng; Gu, Zhaoyan; Pei, Yu; Meng, Ping

    2015-01-01

    Objectives Aging, body composition, and body mass index (BMI) are important factors in bone mineral density (BMD). Although several studies have investigated the various parameters and factors that differentially influence BMD, the results have been inconsistent. Thus, the primary goal of the present study was to further characterize the relationships of aging, body composition parameters, and BMI with BMD in Chinese Han males older than 50 years. Methods The present study was a retrospective analysis of the body composition, BMI, and BMD of 358 Chinese male outpatients between 50 and 89 years of age that were recruited from our hospital between 2009 and 2011. Qualified subjects were stratified according to age and BMI as follows: 50–59 (n = 35), 60–69 (n = 123), 70–79 (n = 93), and 80–89 (n = 107) years of age and low weight (BMI: BMI BMI BMI ≥ 28 kg/m2; n = 41). Dual-energy X-ray absorptiometry (DEXA) was used to assess bone mineral content (BMC), lean mass (LM), fat mass (FM), fat-free mass (FFM), lumbar spine (L1-L4) BMD, femoral neck BMD, and total hip BMD. Additionally, the FM index (FMI; FM/height2), LM index (LMI; LM/height2), FFM index (FFMI; [BMC+LM]/height2), percentage of BMC (%BMC; BMC/[BMC+FM+LM] × 100%), percentage of FM (%FM; FM/[BMC+FM+LM] × 100%), and percentage of LM (%LM; LM/(BMC+FM+LM) × 100%) were calculated. Osteopenia or osteoporosis was identified using the criteria and T-score of the World Health Organization. Results Although there were no significant differences in BMI among the age groups, there was a significant decline in height and weight according to age (p body composition, there were no significant differences in %BMC but there was an increase in %FM (p BMI increased but there were declines in the detection rates of osteoporosis and osteopenia (both p BMI value of 1, a decline in BMI was an independent risk factor of osteoporosis or osteopenia, while an increase in BMI was a protective factor for BMD. At the same time, BMD in L1-L4 exhibited a significant positive association with FMI (p = 0.0003) and the femoral neck and total hip BMDs had significant positive associations with FFMI and LMI, respectively (both p BMI was protective for BMD. LMI and FFMI were protective for BMD in the femoral neck and total hip. PMID:26090818

  20. Radiation Protection

    Science.gov (United States)

    ... EPA United States Environmental Protection Agency Search Search Radiation Protection Share Facebook Twitter Google+ Pinterest Contact Us Radiation Protection Document Library View and download EPA radiation ...

  1. Radiation Therapy

    Science.gov (United States)

    ... the area is stitched shut. Another treatment, called proton-beam radiation therapy , focuses the radiation on the ... after radiation treatment ends. Sore mouth and tooth decay. If you received radiation therapy to the head ...

  2. Radiation sickness

    Science.gov (United States)

    ... radiation. There are two basic types of radiation: ionizing and nonionizing. Nonionizing radiation comes in the form of light, radio waves, microwaves and radar. This kind of radiation usually ...

  3. Radiation dosimetry.

    OpenAIRE

    Cameron, J

    1991-01-01

    This article summarizes the basic facts about the measurement of ionizing radiation, usually referred to as radiation dosimetry. The article defines the common radiation quantities and units; gives typical levels of natural radiation and medical exposures; and describes the most important biological effects of radiation and the methods used to measure radiation. Finally, a proposal is made for a new radiation risk unit to make radiation risks more understandable to nonspecialists.

  4. Cell protection by low doses of ionizing radiation challenges the concept of linearity

    Energy Technology Data Exchange (ETDEWEB)

    Feinendegen, L.E. [Brookhaven National Lab., Upton, NY (United States). Medical Dept.; Bond, V.P. [Washington State Univ., Richland, WA (United States). Research Faculty; Sondhaus, C.A. [Arizona Univ., Tucson, AZ (United States). Dept. of Radiology and Radiation Control Office; Altman, K.I.

    1999-07-01

    Ionizing radiation is known to potentially interfere with cellular functions at all levels. Cell death and late effects such as malignant tumors may result. These stem from permanent damage to cellular DNA, which may lead to maligant transformation of the affected cells. Most such studies have used relatively high values of an absorbed dose, D, above about 0.3 Gy. After acute exposures of humans to between 0.3 and 2 Gy, the risk of cancer in the exposed individuals seems proportional to tissue D. For the purpose of radiation protection, this proportionality is assumed to extend down to zero D. This assumption defines the linear-no-threshold, LNT, hypothesis. In addition to DNA damage, altered intracellular signaling results from acute exposure to cell doses below about 0.3 Gy, and involves radiation-induced reactive oxygen species, ROS. In consequence, different mechanisms of protection against DNA lesions may be induced and last from hours to weeks in different cell types. Damage to DNA is continuously and endogenously produced mainly by ROS generated in a normal oxidative metabolism. This DNA damage quantitatively exceeds by several orders of magnitude that caused by low-dose irradiation. Thus, the protective responses following acute low-dose irradiation may be presumed to mainly prevent and reduce endogenously caused DNA damage. Protective responses are physiological and ubiquitous, albeit differently expressed in various cell types and species. Only in few cases has the induction of such responses been studied that occur after acute low-dose irradiation. Their incidence has been described to be nonlinear, increasing initially with D, beginning to decrease with D when D exceeds about 0.1-0.2 Gy, and eventually disappearing at higher D. Accordingly, the model described here uses two dose-effect functions, one linear for causing and a nonlinear one for reducing DNA damage in the irradiated cells and tissues. The resulting net dose-risk function strongly suggests

  5. Evaluation of the detriment associated with exposure at low doses and low dose rates in the radiation protection system; Evaluation du detriment associe a l'exposition aux faibles doses et faibles debits de dose dans le systeme de radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Vaillant, Ludovic; Schneider, Thierry [CEPN, 28, rue de la Redoute, 92260 Fontenay-aux-Roses (France)

    2012-03-15

    Questions about quantifying the radiological risk associated with exposure to ionising radiation have been debated repeatedly for a variety of exposure situations, including, among others, medical irradiation, discharges from nuclear facilities, transportation of radioactive waste, and potential nuclear accidents. This paper aims to shed light on the link between exposure and risk, focusing on the items that constitute the detriment associated with this exposure. The management of the risk associated with it relies on a cautious hypothesis of a linear no-threshold relation between exposure and risk of death or detriment. The International Commission on Radiological Protection (ICRP) published General Recommendations in 1966 that recognised this relation, but did not publish a quantification of the risk until 1977. The Commission introduced the concept of effective dose as a risk indicator that makes it possible to determine dose limits according to the risk associated with them. In 1990, the Commission proposed a revision of the quantification and construction of detriment. New limits, based on risk quantification and, for the first time, risk tolerability, were proposed. The optimisation of radiation protection - keeping radiation exposure as low as reasonably achievable in light of the economic and social context - became the key principle of the radiation protection system. The use of detriment makes it possible to use economic tools to guide the decision process for this optimisation - by assessing the monetary value of human life. This concept, widely used in health economics during the 1980's, has been criticised by many and must be used cautiously. ICRP published the latest quantifications of detriment in 2007. Detriment is thus an indicator that assesses the risk of death associated with exposure to ionising radiation for an average individual. Its construction relies on simplifying assumptions that are needed to implement a robust and effective

  6. Radiation Therapy

    Science.gov (United States)

    Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

  7. Radiation dosimetry

    CERN Document Server

    Hine, Gerald J; Hine, Gerald J

    1956-01-01

    Radiation Dosimetry focuses on the advancements, processes, technologies, techniques, and principles involved in radiation dosimetry, including counters and calibration and standardization techniques. The selection first offers information on radiation units and the theory of ionization dosimetry and interaction of radiation with matter. Topics include quantities derivable from roentgens, determination of dose in roentgens, ionization dosimetry of high-energy photons and corpuscular radiations, and heavy charged particles. The text then examines the biological and medical effects of radiation,

  8. Radiation protection

    CERN Document Server

    CERN. Geneva

    2001-01-01

    This will be a simple explanation of the reasons why CERN has to be careful about radiation protections issues, a practical guide on how to recognize radiation dangers, the monitoring systems that make sure radiation levels are well tolerable norms, and a quick summary of what radiation levels mean in terms of personal risk.

  9. Radiation Therapy: Professions in Radiation Therapy

    Science.gov (United States)

    ... Resources Professions Site Index A-Z Professions in Radiation Therapy Radiation Oncologist Therapeutic Medical Physicist Radiation Therapist Dosimetrist Radiation Oncology Nurse Social Worker Dietitian Radiation Oncologist Radiation oncologists are physicians who oversee the ...

  10. Pelvic radiation - discharge

    Science.gov (United States)

    Radiation of the pelvis - discharge; Cancer treatment - pelvic radiation; Prostate cancer - pelvic radiation; Ovarian cancer - pelvic radiation; Cervical cancer - pelvic radiation; Uterine cancer - pelvic radiation; Rectal cancer - pelvic radiation

  11. Breast Cancer Profile in a Group of Patients Followed up at the Radiation Therapy Unit of the Yaounde General Hospital, Cameroon

    Directory of Open Access Journals (Sweden)

    J. D. Kemfang Ngowa

    2011-01-01

    Full Text Available Objective. To describe the profile of breast cancer in the patients attending the radiation therapy unit of Yaounde General Hospital. Method. From 1989 to 2009, we conducted a descriptive retrospective study based on the register and medical records of patients. Results. During the study period, 531 breast cancer patients were recorded of which 0.75% were male. Age range was 18 to 82 years, with a mean of 45.17 years. Out of these, 66.1% were less than 50 years old and 31.9% less than 40. Self detection was the discovery method in most cases (95.34% of patients. Mean delay before presentation at hospital was 10.35 months, and 54.94% had used traditional medicine before medical evaluation. Metastasis and locally advanced breast cancer at diagnosis were present in 08.13% and 62.78%, respectively. Mastectomy was used in 88.08% of patients. Conclusion. The study reinforces the position occupied by late presentation and advanced stage at diagnosis of breast cancer profile in developing countries.

  12. Atoms, Radiation, and Radiation Protection

    CERN Document Server

    Turner, James E

    2007-01-01

    Atoms, Radiation, and Radiation Protection offers professionals and advanced students a comprehensive coverage of the major concepts that underlie the origins and transport of ionizing radiation in matter. Understanding atomic structure and the physical mechanisms of radiation interactions is the foundation on which much of the current practice of radiological health protection is based. The work covers the detection and measurement of radiation and the statistical interpretation of the data. The procedures that are used to protect man and the environment from the potential harmful effects of

  13. Radiation Chemistry

    Science.gov (United States)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

  14. Radiation carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Fry, R.J.M.

    1976-01-01

    The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the comparative risks should be examined. In the case of radiation, total dose, fractionation, dose rate, dose distribution, and radiation quality should be considered in the estimation of risk. The biological factors that must be considered include incidence of tumors, latent period, degree of malignancy, and multiplicity of tumors. The risk of radiation induction of tumors is influenced by the genotype, sex, and age of the patient, the tissues that will be exposed, and previous therapy. With chemotherapy the number of cells at risk is usually markedly higher than with radiation therapy. Clearly the problem of the estimation of comparative risks is complex. This paper presents the current views on the comparative risks and the importance of the various factors that influence the estimation of risk.

  15. Radiation acoustics

    CERN Document Server

    Lyamshev, Leonid M

    2004-01-01

    Radiation acoustics is a developing field lying at the intersection of acoustics, high-energy physics, nuclear physics, and condensed matter physics. Radiation Acoustics is among the first books to address this promising field of study, and the first to collect all of the most significant results achieved since research in this area began in earnest in the 1970s.The book begins by reviewing the data on elementary particles, absorption of penetrating radiation in a substance, and the mechanisms of acoustic radiation excitation. The next seven chapters present a theoretical treatment of thermoradiation sound generation in condensed media under the action of modulated penetrating radiation and radiation pulses. The author explores particular features of the acoustic fields of moving thermoradiation sound sources, sound excitation by single high-energy particles, and the efficiency and optimal conditions of thermoradiation sound generation. Experimental results follow the theoretical discussions, and these clearl...

  16. Hawking radiation

    Science.gov (United States)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

  17. Radiation Hydrodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Castor, J I

    2003-10-16

    The discipline of radiation hydrodynamics is the branch of hydrodynamics in which the moving fluid absorbs and emits electromagnetic radiation, and in so doing modifies its dynamical behavior. That is, the net gain or loss of energy by parcels of the fluid material through absorption or emission of radiation are sufficient to change the pressure of the material, and therefore change its motion; alternatively, the net momentum exchange between radiation and matter may alter the motion of the matter directly. Ignoring the radiation contributions to energy and momentum will give a wrong prediction of the hydrodynamic motion when the correct description is radiation hydrodynamics. Of course, there are circumstances when a large quantity of radiation is present, yet can be ignored without causing the model to be in error. This happens when radiation from an exterior source streams through the problem, but the latter is so transparent that the energy and momentum coupling is negligible. Everything we say about radiation hydrodynamics applies equally well to neutrinos and photons (apart from the Einstein relations, specific to bosons), but in almost every area of astrophysics neutrino hydrodynamics is ignored, simply because the systems are exceedingly transparent to neutrinos, even though the energy flux in neutrinos may be substantial. Another place where we can do ''radiation hydrodynamics'' without using any sophisticated theory is deep within stars or other bodies, where the material is so opaque to the radiation that the mean free path of photons is entirely negligible compared with the size of the system, the distance over which any fluid quantity varies, and so on. In this case we can suppose that the radiation is in equilibrium with the matter locally, and its energy, pressure and momentum can be lumped in with those of the rest of the fluid. That is, it is no more necessary to distinguish photons from atoms, nuclei and electrons, than it is

  18. Radiation Exposure

    Science.gov (United States)

    ... on to any children you have after the exposure. A lot of radiation over a short period, ... skin burns and reduced organ function. If the exposure is large enough, it can cause premature aging ...

  19. Radiation damage

    CERN Document Server

    Heijne, Erik H M; CERN. Geneva

    1998-01-01

    a) Radiation damage in organic materials. This series of lectures will give an overview of radiation effects on materials and components frequently used in accelerator engineering and experiments. Basic degradation phenomena will be presented for organic materials with comprehensive damage threshold doses for commonly used rubbers, thermoplastics, thermosets and composite materials. Some indications will be given for glass, scintillators and optical fibres. b) Radiation effects in semiconductor materials and devices. The major part of the time will be devoted to treat radiation effects in semiconductor sensors and the associated electronics, in particular displacement damage, interface and single event phenomena. Evaluation methods and practical aspects will be shown. Strategies will be developed for the survival of the materials under the expected environmental conditions of the LHC machine and detectors. I will describe profound revolution in our understanding of black holes and their relation to quantum me...

  20. Radiation Transport

    Energy Technology Data Exchange (ETDEWEB)

    Urbatsch, Todd James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  1. Radiation Protection

    Energy Technology Data Exchange (ETDEWEB)

    Loos, M

    2001-04-01

    Major achievements of SCK-CEN's Radiation Protection Department in 2000 are described. The main areas for R and D of the department remain neutron dosimetry and neutron activation analysis, safeguards information handling and non-destructive assay techniques. Further activities include low-level radioactivity measurements in environmental and biological samples and radiation protection research. Finally, achievements in decision strategy research and social sciences in nuclear research are reported.

  2. Synchrotron radiation with radiation reaction

    Science.gov (United States)

    Nelson, Robert W.; Wasserman, Ira

    1991-04-01

    A rigorous discussion is presented of the classical motion of a relativistic electron in a magnetic field and the resulting electromagnetic radiation when radiation reaction is important. In particular, for an electron injected with initial energy gamma(0), a systematic perturbative solution to the Lorentz-Dirac equation of motion is developed for field strengths satisfying gamma(0) B much less than 6 x 10 to the 15th G. A particularly accurate solution to the electron orbital motion in this regime is found and it is demonstrated how lowest-order corrections can be calculated. It is shown that the total energy-loss rate corresponds to what would be found using the exact Larmor power formula without including radiation reaction. Provided that the particle energy and field strength satisfy the same contraint, it is explicitly demonstrated that the intuitive prescription for calculating the time-integrated radiation spectrum described above is correct.

  3. Abdominal radiation - discharge

    Science.gov (United States)

    Radiation - abdomen - discharge; Cancer - abdominal radiation; Lymphoma - abdominal radiation ... When you have radiation treatment for cancer, your body goes through changes. About 2 weeks after radiation treatment starts, you might notice changes ...

  4. Brain radiation - discharge

    Science.gov (United States)

    Radiation - brain - discharge; Cancer-brain radiation; Lymphoma - brain radiation; Leukemia - brain radiation ... Decadron) while you are getting radiation to the brain. It may make you hungrier, cause leg swelling ...

  5. Directional radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, Jonathan L.

    2017-09-12

    Directional radiation detectors and systems, methods, and computer-readable media for using directional radiation detectors to locate a radiation source are provided herein. A directional radiation detector includes a radiation sensor. A radiation attenuator partially surrounds the radiation sensor and defines an aperture through which incident radiation is received by the radiation sensor. The aperture is positioned such that when incident radiation is received directly through the aperture and by the radiation sensor, a source of the incident radiation is located within a solid angle defined by the aperture. The radiation sensor senses at least one of alpha particles, beta particles, gamma particles, or neutrons.

  6. Cherenkov radiation; La radiation Cerenkov

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    When the radioactivity has been discovered, it was observed by researchers that different materials as mineral salts or solutions were emitting a weak light when submitted to radioactivity beams. At the beginning it has been thought that it was fluorescent light. In 1934, Cherenkov, a russian physicist, worked on the luminescence of uranyl salts solutions caused by gamma radiation and observed a very weak light was emitted by pure liquid. After further studies, he concluded that this phenomena was different from fluorescence. Since then, it has been called Cherenkov effect. This blue light emission is produced when charged particles are going through a transparent medium with an upper velocity than light velocity. This can happen only in medium with large refractive index as water or glass. It also presents its different properties discovered afterwards. The different applications of the Cherenkov radiation are discussed as counting techniques for radiation detectors or comic ray detectors. (M.P.)

  7. Radiation Technology Against Bioterrorism

    Science.gov (United States)

    2004-10-25

    application of radiation processing: radiation crosslinking of polymers and radiation sterilization of health care products have developed into substantial...municipal waste water, • radiation inactivation of bioterrorism agents, • electron beam processing of flue gases, • radiation crosslinking , • radiation...Electron beam processing of flue gases 6. Radiation crosslinking 7. Radiation curing 3 Radiation Technology Against Bioterrorism L.G. Gazsó and G

  8. Space Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R.

    1968-01-01

    This booklet discusses three kinds of space radiation, cosmic rays, Van Allen Belts, and solar plasma. Cosmic rays are penetrating particles that we cannot see, hear or feel, which come from distant stars. Van Allen Belts, named after their discoverer are great belts of protons and electrons that the earth has captured in its magnetic trap. Solar plasma is a gaseous, electrically neutral mixture of positive and negative ions that the sun spews out from convulsed regions on its surface.

  9. Radiation protection

    CERN Multimedia

    Radioactive Shipping Service

    2005-01-01

    The section of the radiation protection group in charge of shipping radioactive material would like to remind users that all radioactive material leaving CERN must be checked for radioactivity and must be shipped according to the procedure given at http://cern.ch/service-rp-shipping Do not hesitate to contact us for any question or control. Radioactive Shipping Service: service-rp-shipping@cern.ch Tél. 73171

  10. Radiation protection

    CERN Document Server

    2005-01-01

    The section of the Radiation Protection Group in charge of shipping radioactive material would like to remind users that all radioactive material leaving CERN must be checked for radioactivity and must be shipped according to the procedure given at http://cern.ch/service-rp-shipping Do not hesitate to contact us for any question or control. Radioactive Shipping Service: service-rp-shipping@cern.ch Tel. 73171

  11. Radiation protection

    CERN Multimedia

    2005-01-01

    The section of the Radiation Protection Group in charge of shipping radioactive material would like to remind users that all radioactive material leaving CERN must be checked for radioactivity and must be shipped according to the procedure given at http://cern.ch/service-rp-shipping Do not hesitate to contact us for any question or control. Radioactive Shipping Service: service-rp-shipping@cern.ch Tél. 73171

  12. Radiatively Generated $\

    CERN Document Server

    Joshipura, A S; Joshipura, Anjan S.; Rindani, Saurabh D.

    2003-01-01

    We study the consequences of assuming that the mass scale $\\Delta_{odot}$ corresponding to the solar neutrino oscillations and mixing angle $U_{e3}$ corresponding to the electron neutrino oscillation at CHOOZ are radiatively generated through the standard electroweak gauge interactions. All the leptonic mass matrices having zero $\\Delta_{odot}$ and $U_{e3}$ at a high scale lead to a unique low energy value for the $\\Delta_{odot}$ which is determined by the (known) size of the radiative corrections, solar and the atmospheric mixing angle and the Majorana mass of the neutrino observed in neutrinoless double beta decay. This prediction leads to the following consequences: ($i$) The MSSM radiative corrections generate only the dark side of the solar neutrino solutions. ($ii$) The inverted mass hierarchy ($m,-m,0$) at the high scale fails in generating the LMA solution but it can lead to the LOW or vacuum solutions. ($iii$) The $\\Delta_{odot}$ generated in models with maximal solar mixing at a high scale is zero t...

  13. Radiation Engineering for Designers

    Science.gov (United States)

    Pellish, Jonathan A.

    2015-01-01

    This tutorial provides an overview of the natural space radiation environment, an introduction to radiation effect types, an overview of EEE parts selection, scrubbing, and radiation mitigation, and an introduction to radiation testing.

  14. Acute Radiation Syndrome

    Science.gov (United States)

    ... Matters Information on Specific Types of Emergencies Acute Radiation Syndrome (ARS): A Fact Sheet for the Public ... is called the radiation dose. People exposed to radiation will get ARS only if: The radiation dose ...

  15. Chest radiation - discharge

    Science.gov (United States)

    Radiation - chest - discharge; Cancer - chest radiation; Lymphoma - chest radiation ... When you have radiation treatment for cancer, your body goes through changes. About 2 weeks after your first treatment: It may be hard ...

  16. Risk Factors: Radiation

    Science.gov (United States)

    Radiation of certain wavelengths, called ionizing radiation, has enough energy to damage DNA and cause cancer. Ionizing radiation includes radon, x-rays, gamma rays, and other forms of high-energy radiation.

  17. Radiation Engineering for Designers

    Science.gov (United States)

    Pellish, Jonathan A.

    2015-01-01

    This tutorial provides an overview of the natural space radiation environment, an introduction to radiation effect types, an overview of EEE parts selection, scrubbing, and radiation mitigation, and an introduction to radiation testing.

  18. Dose assessment for the fetus considering scattered and secondary radiation from photon and proton therapy when treating a brain tumor of the mother

    Science.gov (United States)

    Geng, Changran; Moteabbed, Maryam; Seco, Joao; Gao, Yiming; Xu, X. George; Ramos-Méndez, José; Faddegon, Bruce; Paganetti, Harald

    2016-01-01

    The goal of this work was to determine the scattered photon dose and secondary neutron dose and resulting risk for the sensitive fetus from photon and proton radiotherapy when treating a brain tumor during pregnancy. Anthropomorphic pregnancy phantoms with three stages (3-, 6-, 9-month) based on ICRP reference parameters were implemented in Monte Carlo platform TOPAS, to evaluate the scattered dose and secondary neutron dose and dose equivalent. To evaluate the dose equivalent, dose averaged quality factors were considered for neutrons. This study compared three treatment modalities: passive scattering and pencil beam scanning proton therapy (PPT and PBS) and 6-MV 3D conformal photon therapy. The results show that, for 3D conformal photon therapy, the scattered photon dose equivalent to the fetal body increases from 0.011 to 0.030 mSv per treatment Gy with increasing stage of gestation. For PBS, the neutron dose equivalent to the fetal body was significantly lower, i.e. increasing from 1.5  ×  10-3 to 2.5  ×  10-3 mSv per treatment Gy with increasing stage of gestation. For PPT, the neutron dose equivalent of the fetus decreases from 0.17 to 0.13 mSv per treatment Gy with the growing fetus. The ratios of dose equivalents to the fetus for a 52.2 Gy(RBE) course of radiation therapy to a typical CT scan of the mother’s head ranged from 3.4-4.4 for PBS, 30-41 for 3D conformal photon therapy and 180-500 for PPT, respectively. The attained dose to a fetus from the three modalities is far lower than the thresholds of malformation, severe mental retardation and lethal death. The childhood cancer excessive absolute risk was estimated using a linear no-threshold dose-response relationship. The risk would be 1.0 (95% CI: 0.6, 1.6) and 0.1 (95% CI:  -0.01, 0.52) in 105 for the 9-month fetus for PBS with a prescribed dose of 52.2 Gy(RBE). The increased risks for PPT and photon therapy are about two and one orders of magnitude larger than that for PBS

  19. Evaluation of Fe and Zn/Cu ratio in serum of patients with sickle cell anemia by total reflection X-ray fluorescence using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Canellas, Catarine G.L.; Leitao, Roberta G.; Lopes, Ricardo T., E-mail: catarine@lin.ufrj.b, E-mail: ricardo@lin.ufrj.b [Universidade Federal do Rio de Janeiro (PEN/COPPE/UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-Graduacao de Engenharia. Programa de Engenharia Nuclear. Lab. de Instrumentaco Nuclear; Carvalho, Silvia M.F., E-mail: silvia@hemorio.rj.gov.b [State Institute of Hematology Arthur de Siqueira Cavalcanti (HEMORIO), Rio de Janeiro, RJ (Brazil); Bellido, Alfredo Victor B., E-mail: alfredo@ien.gov.b [Federal Fluminense University (UFF), Niteroi, RJ (Brazil). Chemistry Inst.; Anjos, Marcelino J., E-mail: marcelin@lin.ufrj.b [State University of Rio de Janeiro (UERJ), RJ (Brazil). Physics Inst.

    2011-07-01

    Sickle cell anemia (SCA) is a blood disorder that affects hemoglobin, the protein found in red blood cells that help carry oxygen throughout the body. In this work we have analyzed serum samples from patients with SCA by using total reflection X-ray fluorescence using synchrotron radiation (SRTXRF). The SRTXRF measurements were performed at the X-ray fluorescence beamline at Brazilian National Synchrotron Light Laboratory (LNLS), in Campinas, Sao Paulo using a polychromatic beam. We have studied forty-three patients aged 18-50 years old, suffering from SCA and Sixty healthy volunteers aged 18-60 years old. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Student's t-test was applied in order to check whether the two populations (CG x SCA) had the same mean values. It was observed that elemental concentration of P, Cl, K, Fe, Cu, Zn and Br differed significantly ({alpha} = 0.05) between groups of healthy subjects and SCA. The concentrations of K, Fe and Cu in the serum samples of patients with SCA were larger 15%, 120 % and 20 %, respectively, when compared with the CG. On the other hand, the concentrations of P (-20 %), Cl (-6 %), Zn (-25 %) and Br (-22 %) were smaller than the values determined for the control group. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples of patients with SCA group than the CG. So, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. (author)

  20. Radiation pneumonitis

    Energy Technology Data Exchange (ETDEWEB)

    Amla, T.R.; Chakravarti, R.N.; Lal, K.

    1975-07-01

    Adult healthy rhesus monkeys were exposed to a course of roentgen irradiation over the chest and back to produce pulmonary changes simulating human radiation pneumonitis. Macroscopic and morphologic changes included dense adhesions, pleural thickening and increased consistency of the lungs. Microscopically the early reaction was characterized by dilatation of pulmonary vessels, microhaemorrhages, collapse of alveoli, permeation of the interstitial tissue with a fibrinous fluid and cells. In the late stage the fibrinous interstitial matrix was replaced by hyaline eosinophilic mass, fragmentation and dissolution of the elastic tissue and thickening of the alveolar walls. The cell population in the interstitial tissue showed decline and at places radiolytic effect. There was peribronchial and perivascular fibrosis and hyalinization and pulmonary arteries revealed marked degree of arteriosclerosis. The present study opens a new field for experimental research on the development of pulmonary hypertension as a post-irradiation complication.

  1. Radiation Insulation

    Science.gov (United States)

    1995-01-01

    The Apollo and subsequent spacecraft have had highly effective radiation barriers; made of aluminized polymer film, they bar or let in heat to maintain consistent temperatures inside. Tech 2000, formerly Quantum International Corporation used the NASA technology in its insulating materials, Super "Q" Radiant Barrier, for home, industry and mobile applications. The insulation combines industrial aluminum foil overlaid around a core of another material, usually propylene or mylar. The outer layer reflects up to 97 percent of heat; the central layer creates a thermal break in the structure and thus allows low radiant energy emission. The Quantum Cool Wall, used in cars and trucks, takes up little space while providing superior insulation, thus reducing spoilage and costs. The panels can also dampen sound and engine, exhaust and solar heat.

  2. Breast radiation - discharge

    Science.gov (United States)

    Radiation - breast - discharge ... away around 4 to 6 weeks after the radiation treatment is over. You may notice changes in ... breast looks or feels (if you are getting radiation after a lumpectomy). These changes include: Soreness or ...

  3. Pregnancy and Radiation Exposure

    Science.gov (United States)

    ... RadiationAnswers.org Ask the Experts Pregnancy and Radiation Exposure Robert Brent, MD, PhD The following information pertains to reproductive risks of radiation exposures to women who are pregnant and have questions ...

  4. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Siegel, Robert

    2016-01-01

    Further expanding on the changes made to the fifth edition, Thermal Radiation Heat Transfer, 6th Edition continues to highlight the relevance of thermal radiative transfer and focus on concepts that develop the radiative transfer equation (RTE). The book explains the fundamentals of radiative transfer, introduces the energy and radiative transfer equations, covers a variety of approaches used to gauge radiative heat exchange between different surfaces and structures, and provides solution techniques for solving the RTE.

  5. 三峡库区18岁及以上居民高血压患病率及影响因素分析%Analysis on prevalence of hypertension and its associated factors among residents over 50 years old in Three Gorge Areas

    Institute of Scientific and Technical Information of China (English)

    漆莉; 丁贤彬; 毛德强; 冯连贵; 吕晓燕; 张春华; 焦艳; 李洪

    2011-01-01

    目的:了解三峡工程重庆库区(以下简称"三峡库区")18岁及以上居民的高血压患病率及影响因素,为库区开展慢性病防控工作提供建议.方法:利用多阶段随机抽样的方法抽取三峡库区18岁及以上居民2 700人,进行现场问卷调查和体格测量,对核心指标进行描述性统计分析,将*9字2检验选定的有统计学意义的指标纳入多因素Logistic回归,分析判定库区居民高血压的影响因素.结果:有效完成问卷调查和体格测量2 699人,其中高血压患者751人,粗患病率27.8%,年龄标化患病率24.0%.多因素回归分析发现年龄、职业、豆制品及水果食用频率、进食泡菜或咸菜习惯、体质指数是库区居民高血压的独立影响因素.结论:三峡库区居民高血压患病率高,防控形势严峻,应采取有针对性的措施加强该人群的高血压防控力度.%To understand the prevalence of hypertension and its associated factors among residents over 18 years old a- mong Three Gorge Areas in Chongqing so as to provide scientific evidence for non-communicable disease prevention and control. Methods:2 700 residents over 18 years old were sampled by multi-stage stratified random sampling. They were interviewed face-to- face with questionnaire and with physical examination. The influencing factors were identified by multi-variate logistic regression analysis model respectively. Results: A total of 2 699 residents were investigated, of them ,751 cases of hypertension were found. Its prevalence was 27.8%. The risk factors included age, occupation, eating frequency of bean products, fruit and pickle ;BMI were associated with hypertension significantly. Conclusion: The prevalence of hypertension is high among Three Gorge Areas in Chongqing. It is urgent to conduct targeted measures for the prevention and control of hypertension.

  6. 玉溪市某医院≥50岁及<50岁人群HIV/AIDS疫情对比分析%Analysis and Comparison of HIV/AIDS Population under and Above 50-year-old in Yuxi Prefecture

    Institute of Scientific and Technical Information of China (English)

    李世福; 郭春园; 李再友; 付金翠; 鲁建波; 刘小春; 陈良; 潘丽; 高良敏

    2016-01-01

    目的 了解玉溪市≥50岁人群艾滋病病毒感染者/艾滋病病人(HIV/AIDS)病例占总报告数比的上升原因,对其疫情做较全面分析.方法 通过问卷调查、HIV阳性检出率、新近感染状况、首次CD4+T淋巴细胞计数<200情况对本院≥50岁人群疫情进行综合分析.结果 问卷调查显示≥50岁人群艾滋病知识知晓较比较组低(P <0.001),且较少获得相关宣传,但其主要通过医院途径获取艾滋病检测且有更多机会获得检测(P <0.001);2010-2013年玉溪市人民医院90 778例住院及手术病人阳性检出率为0.59%,其中≥50岁组与比较组阳性检出率分别为0.41%和0.68%,近年≥50岁组检出率并未出现上升趋势(P=0.121)而比较组却出现上升趋势(P <0.001);2007-2013年35.80%新报告≥50岁人群感染者首次CD4+T淋巴细胞计数小于200,18.96%新报告比较组感染者首次CD4+T淋巴细胞计数小于200,差异有统计学意义(P=0.001).结论 玉溪市≥50岁人群艾滋病知晓率低,但是有更多机会通过医院获得艾滋病检测;阳性检出率较低且近年无上升趋势;新近感染比例及首次CD4+T淋巴细胞计数结果显示其可能多年前就已经感染而近年才通过扩大检测发现,需持续追踪调查≥50岁人群艾滋痛疫情.%Objective To understand why the proportion of people aged 50 or more among all new reports HIV/AIDS was rising and analyze the epidemic situation of the AIDS among the elderly in Yuxi Prefecture.Methods Analysed the epidemic situation through the questionnaire survey, positive rate, recent HIV-1 infection, primary CD4 + T cell counts less than 200.Results The questionnaire survey showed that the awareness rate of AIDS knowledge in people aged 50 or more was lower than control group (P < 0.001) and less access to HIV education, but the people aged 50 or more was access to HIV testing more easily through hospitals (P <0.001).The HIV/AIDS positive rate was 0.59% in the First People's Hospital of Yuxi from 2010 to 2013, among them the positive rate of the people aged 50 or more and the control group, 0.41% vs 0.68%.The positive rate of the people aged 50 did not show rising trend (P =0.121), but the control group seemed rising P < 0.001).Among the people aged 50 or more HIV/AIDS, 35.80% primary CD4 + T cell counts less than 200, among the control group HIV/AIDS, 18.96% primary CD4 + T cell counts less than 200, and there was a statistical significance (P =0.001).Conclusion Compared with control group, the awareness rate of AIDS knowledge in people aged 50 or older was low but they access to HIV testing more easily through hospitals.Positive rate was low and had no obvious rising trend in recent years.The result of CD4 + T cell counts and recent HIV-1 infection showed that the people aged 50 or older was likely to be infected years ago and was found through expanded HIV testing.It needs to further investigate the epidemic situation in people aged 50 or older continuously.

  7. Mulheres com idade igual ou superior a 50 anos: ações preventivas da infecção pelo HIV Mujeres com edad igual o superior a 50 años: acciones preventivas de la infección por el VIH The 50-year-old women or older: preventive actions to the HIV infection

    Directory of Open Access Journals (Sweden)

    Daniela Angelo de Lima Rodrigues

    2010-06-01

    Full Text Available Trata-se de pesquisa qualitativa que buscou verificar a adoção de ações preventivas da transmissão do HIV por mulheres com idade igual ou superior a 50 anos, moradoras em uma comunidade de baixa renda e atendidas pelo Programa Saúde da Família, no Município de São Paulo. Adotou-se como referencial teórico a Antropologia Médica e, para o tratamento dos dados, o Discurso do Sujeito Coletivo. Foram entrevistadas 13 mulheres e são apresentados três discursos: valorizando a prevenção; invisibilidade do HIV/aids; e rejeição à adesão ao preservativo. A análise mostrou que o grupo não se percebia em risco à infecção pela via sexual devido à confiança na fidelidade do parceiro. O eventual uso do preservativo foi atribuído somente à curiosidade. As ações preventivas adotadas carecem de embasamento científico. Os resultados alertam para a necessidade do planejamento e da implementação de intervenções culturalmente embasadas direcionadas ao segmento estudado.Se trata de una investigación cualitativa que buscó verificar la adopción de acciones preventivas de la transmisión del VIH por mujeres con edad igual o superior a 50 años, moradoras en una comunidad de baja renta y atendidas por el Programa Salud de la Familia, en el municipio de São Paulo, Brasil. Se adoptó como referencial teórico la Antropología Médica y, para el tratamiento de los datos, el Discurso del Sujeto Colectivo. Se entrevistaron 13 mujeres y son presentados tres discursos: valorar la prevención; invisibilidad del VIH/SIDA; rechazo a la adherencia al preservativo. El análisis apuntó que el grupo no percibió el riesgo a la infección por la vía sexual a causa de la confianza en la fidelidad del compañero. El eventual uso del preservativo fue atribuido solamente a la curiosidad. Las acciones preventivas adoptadas carecen de base científica. Los resultados alertan para la necesidad del planeamiento y de la implantación de intervenciones culturalmente basadas direccionada al seguimiento estudiado.The present study is a qualitative research which aimed to verify the adoption of preventive measures on the transmission of HIV in women aged 50 or over it, who live in poor communities and were followed by the Family Health Program in São Paulo, Brazil. Medical Anthropology has been adopted as a theoretical reference as well as the Discourse of the Collective Individual for data analysis. There have been 13 women interviewed and three discourses have been presented: prevention appreciation, invisibility of HIV/aids and the rejection of the use of condom. The analysis has shown that the group did not realize the risk of contamination through sexual intercourse due to trust in their partners' loyalty. The casual use of condoms was taken into consideration just out of curiosity. The preventive actions adopted need more scientific basis. The results point out the necessity of planning and implementation of interventions which are culturally based and directed to the studied segment.

  8. RELATIONSHIP BETWEEN ABILITY OF DAILY LIFE AND DEPRESSIVE SYMPTOMS AMONG PEOPLE OVER 50 YEARS OLD IN A COMMUNITY%某社区50岁以上人群日常生活能力与抑郁症状关系

    Institute of Scientific and Technical Information of China (English)

    陶兴永; 李迎春; 阮亮; 胡传来

    2006-01-01

    目的:了解社区50岁以上人群日常生活能力与抑郁症状的关系.方法:应用整群随机抽样的方法对合肥市某社区50岁以上人群日常生活活动能力及抑郁情况进行问卷调查,分析老年人日常生活能力与抑郁的关系.结果:ADL受损者有21人,受损率为6.9%;IADL受损者有59人,受损率为19.4%.分别以ADL、IADL受损与未受损进行组间比较,显示SDS得分及抑郁症状检出率均具差异有统计学意义.单因素logistic回归显示ADL、IADL、配偶、生活赡养等4项因素是社区50岁以上人群抑郁的主要危险因素,多因素回归显示仅IADL为抑郁的独立危险因素.结论:社区50岁以上人群日常生活能力受损明显,提高日常生活能力对防治老年人抑郁,改善老年人生存质量有重要意义.

  9. 瑜伽习练对35~50岁女性身体机能与心理健康水平影响的实验研究%35-50 year-old women practicing yoga on physical function and mental health

    Institute of Scientific and Technical Information of China (English)

    张丽华; 徐细根

    2010-01-01

    通过瑜伽习练对35-50岁女性身体机能与心理健康水平影响的研究,发现:1)瑜伽习练能显著地改善35-50岁女性的身体形态与机能.2)实验后实验组心理健康总分和各因子得分有了不同程度的下降,与时照组相比,躯体化、强迫症状、抑郁、焦虑和心理健康总分具有显著差异,说明瑜伽习练能显著提高35-50岁女性心理健康的水平.3)时间具有主效应,习练周期的长短对35-50岁女性的心理健康存在显著性影响,对于瑜伽习练的女性来说,必须长期坚持,养成习惯,使瑜伽习练的健康效益长期发挥作用.

  10. Radiation controlling reversible window

    Energy Technology Data Exchange (ETDEWEB)

    Gell, H.A. Jr.

    1980-01-01

    A coated glass glazing system is presented including a transparent glass substrate having one surface coated with a radiation absorptive film which is overcoated with a radiation reflective film by a technique which renders the radiation reflective film radiation absorptive at the surface contracting the radiating absorptive film. The coated glass system is used as glazing for storm windows which are adapted to be reversible so that the radiation reflective surface may be exposed to the outside of the dwelling during the warm seasons to prevent excessive solar radiation from entering a dwelling and reversed during cold seasons to absorb solar radiation and utilize it to aid in keeping the dwelling interior warm.

  11. Shielding for Critical Organs and Radiation Exposure Dose Distribution in Patients with High Energy Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Chu, Sung Sil; Suh, Chang Ok; Kim, Gwi Eon [Yonsei Univ., Seoul (Korea, Republic of)

    2002-03-15

    High energy photon beams from medical linear accelerators produce large scattered radiation by various components of the treatment head, collimator and walls or objects in the treatment room including the patient. These scattered radiation do not provide therapeutic dose and are considered a hazard from the radiation safety perspective. Scattered dose of therapeutic high energy radiation beams are contributed significant unwanted dose to the patient. ICRP take the position that a dose of 500mGy may cause abortion at any stage of pregnancy and that radiation detriment to the fetus includes risk of mental retardation with a possible threshold in the dose response relationship around 100 mGy for the gestational period. The ICRP principle of As Low As Reasonably Achievable (ALARA) was recommended for protection of occupation upon the linear no-threshold dose response hypothesis for cancer induction. We suggest this ALARA principle be applied to the fetus and testicle in therapeutic treatment. Radiation dose outside a photon treatment filed is mostly due to scattered photons . This scattered dose is a function of the distance from the beam edge, treatment geometry, primary photon energy, and depth in the patient. The need for effective shielding of the fetus and testicle is reinforced when young patients are treated with external beam radiation therapy and then shielding designed to reduce the scattered photon dose to normal organs have to considered. Irradiation was performed in phantom using high energy photon beams produced by a Varian 2100C/D medical linear accelerator (Varian Oncology Systems, Polo Alto, CA) located at the Yonsei Cancer Center. The composite phantom used was comprised of a commercially available anthropomorphic Rando phantom (Phantom Laboratory Inc., Salem, YN) and a rectangular solid polystyrene phantom of dimensions 30cm x 30cm x 20cm. The anthropomorphic Rando phantom represents an average man made from tissue equivalent materials that is

  12. Detection of Terahertz Radiation

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a system for detecting terahertz radiation, a camera device, and a method for detecting terahertz radiation.......The present invention relates to a system for detecting terahertz radiation, a camera device, and a method for detecting terahertz radiation....

  13. Gravitation radiation observations

    OpenAIRE

    Glass, E. N.

    2017-01-01

    The notion of gravitational radiation begins with electromagnetic radiation. In 1887 Heinrich Hertz, working in one room, generated and received electromagnetic radiation. Maxwell's equations describe the electromagnetic field. The quanta of electromagnetic radiation are spin 1 photons. They are fundamental to atomic physics and quantum electrodynamics.

  14. Micromechanical radiation dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Thundat, T.; Sharp, S.L.; Fisher, W.G.; Warmack, R.J.; Wachter, E.A. (Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6123 (United States))

    1995-03-20

    We demonstrate the use of microcantilevers coated with ultraviolet cross-linking polymers as optical radiation dosimeters. Upon exposure to radiation, a treated cantilever bends due to stress and its resonance frequency increases due to stiffening. These phenomena can be used to develop sensitive radiation dosimeters which respond to radiation affecting the mechanical properties of the selected coating.

  15. Wireless radiation sensor

    Science.gov (United States)

    Lamberti, Vincent E.; Howell, Jr, Layton N.; Mee, David K.; Kress, Reid L.

    2016-08-09

    Disclosed is a sensor for detecting radiation. The sensor includes a ferromagnetic metal and a radiation sensitive material coupled to the ferromagnetic metal. The radiation sensitive material is operable to change a tensile stress of the ferromagnetic metal upon exposure to radiation. The radiation is detected based on changes in the magnetic switching characteristics of the ferromagnetic metal caused by the changes in the tensile stress.

  16. Plutonium radiation surrogate

    Science.gov (United States)

    Frank, Michael I [Dublin, CA

    2010-02-02

    A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

  17. Radiation protection at synchrotron radiation facilities.

    Science.gov (United States)

    Liu, J C; Vylet, V

    2001-01-01

    A synchrotron radiation (SR) facility typically consists of an injector, a storage ring, and SR beamlines. The latter two features are unique to SR facilities, when compared to other types of accelerator facilities. The SR facilities have the characteristics of low injection beam power, but high stored beam power. The storage ring is generally above ground with people occupying the experimental floor around a normally thin concrete ring wall. This paper addresses the radiation issues, in particular the shielding design, associated with the storage ring and SR beamlines. Normal and abnormal beam losses for injection and stored beams, as well as typical storage ring operation, are described. Ring shielding design for photons and neutrons from beam losses in the ring is discussed. Radiation safety issues and shielding design for SR beamlines, considering gas bremsstrahlung and synchrotron radiation, are reviewed. Radiation source terms and the methodologies for shielding calculations are presented.

  18. ERLN Radiation Focus Area

    Science.gov (United States)

    As part of the Environmental Response Laboratory Network, the National Air and Radiation Environmental Laboratory (NAREL) here provides your laboratory with access to radiation-specific laboratory guidance documents and training courses.

  19. Radiation therapy -- skin care

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000735.htm Radiation therapy - skin care To use the sharing features ... this page, please enable JavaScript. When you have radiation treatment for cancer, you may have some changes ...

  20. Hendee's radiation therapy physics

    CERN Document Server

    Pawlicki, Todd; Starkschall, George

    2016-01-01

    The publication of this fourth edition, more than ten years on from the publication of Radiation Therapy Physics third edition, provides a comprehensive and valuable update to the educational offerings in this field. Led by a new team of highly esteemed authors, building on Dr Hendee’s tradition, Hendee’s Radiation Therapy Physics offers a succinctly written, fully modernised update. Radiation physics has undergone many changes in the past ten years: intensity-modulated radiation therapy (IMRT) has become a routine method of radiation treatment delivery, digital imaging has replaced film-screen imaging for localization and verification, image-guided radiation therapy (IGRT) is frequently used, in many centers proton therapy has become a viable mode of radiation therapy, new approaches have been introduced to radiation therapy quality assurance and safety that focus more on process analysis rather than specific performance testing, and the explosion in patient-and machine-related data has necessitated an ...

  1. Cell Radiation Experiment System

    Science.gov (United States)

    Morrison, Dennis R.

    2010-01-01

    The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

  2. Environmental Radiation Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Environmental Radiation Data (ERD) is an electronic and print journal compiled and distributed quarterly by the Office of Radiation and Indoor Air's National Air...

  3. Radiation processing in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    Economic scale of radiation application in the field of industry, agriculture and medicine in Japan in 1997 was investigated to compare its economic impacts with that of nuclear energy industry. Total production value of radiation application accounted for 54% of nuclear industry including nuclear energy industry and radiation applications in three fields above. Industrial radiation applications were further divided into five groups, namely nondestructive test, RI instruments, radiation facilities, radiation processing and ion beam processing. More than 70% of the total production value was brought about by ion beam processing for use with IC and semiconductors. Future economic prospect of radiation processing of polymers, for example cross-linking, EB curing, graft polymerization and degradation, is reviewed. Particular attention was paid to radiation vulcanization of natural rubber latex and also to degradation of natural polymers. (S. Ohno)

  4. Environmental Radiation Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Environmental Radiation Data (ERD) is an electronic and print journal compiled and distributed quarterly by the Office of Radiation and Indoor Air's National Air and...

  5. Radiation effects in semiconductors

    CERN Document Server

    2011-01-01

    There is a need to understand and combat potential radiation damage problems in semiconductor devices and circuits. Written by international experts, this book explains the effects of radiation on semiconductor devices, radiation detectors, and electronic devices and components. These contributors explore emerging applications, detector technologies, circuit design techniques, new materials, and innovative system approaches. The text focuses on how the technology is being used rather than the mathematical foundations behind it. It covers CMOS radiation-tolerant circuit implementations, CMOS pr

  6. Synchrotron radiation facilities

    CERN Multimedia

    1972-01-01

    Particularly in the past few years, interest in using the synchrotron radiation emanating from high energy, circular electron machines has grown considerably. In our February issue we included an article on the synchrotron radiation facility at Frascati. This month we are spreading the net wider — saying something about the properties of the radiation, listing the centres where synchrotron radiation facilities exist, adding a brief description of three of them and mentioning areas of physics in which the facilities are used.

  7. Heart and radiation

    Directory of Open Access Journals (Sweden)

    Lauro Martins Júnior

    2011-12-01

    Full Text Available ABSTRATC The heart exposition to ionizing radiation may produce lesions in cardiac structures, acute (in most of cases benign and reversible, or months and even years later. There is a direct relationship of severity of lesions with radiation doses. The clinical picture receives a new denomination: radiation induced cardiopathy. The more frequent use of radiation in diagnosis and therapeutics increases the importance of their knowledge and especially their prevention.

  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. Hybrid radiator cooling system

    Science.gov (United States)

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  10. (Mis)Understanding Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, Stephen Bruce [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-10

    This set of slides discusses radiation and fears concerning it at a non-technical level. Included are some misconceptions and practical consequences resulting from these. The concept of radiation hormesis is explained. The author concludes that a number of significant societal benefits are being foregone because of overly cautious concerns about low-level radiation.

  11. Ultraviolet radiation and immunosuppression.

    LENUS (Irish Health Repository)

    Murphy, G M

    2009-11-01

    Ultraviolet (UV) radiation is a complete carcinogen. The effects of UV radiation are mediated via direct damage to cellular DNA in the skin and suppression of image surveillance mechanisms. In the context of organ transplantation, addiction of drugs which suppress the immune system add greatly to the carcinogenicity of UV radiation. This review considers the mechanisms of such effects.

  12. Radiation bioengineering; Bioinzynieria radiacyjna

    Energy Technology Data Exchange (ETDEWEB)

    Rosiak, J.M. [Politechnika Lodzka, Lodz (Poland). Inst. Techniki Radiacynej

    1997-10-01

    Radiation processing for modification of different properties of materials being designed for medical use have been described. Especially the polymers as very often used for medical equipment production have been modified by radiation. The different medical applications of biomaterials based on radiation modified polymers have been presented. 13 refs.

  13. Biological implications of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bond, V.P.

    1977-01-01

    Some topics discussed are as follows: effects of diagnostic and therapeutic radiation on dividing cells, DNA, and blood cells; radiation sickness in relation to dose; early and late effects of radiation; effects of low dose irradiation; dose-effect curves; radioinduction of tumors in animals; and incidence of cancer in children following in utero exposure to diagnostic x rays. (HLW)

  14. Topics in radiation dosimetry radiation dosimetry

    CERN Document Server

    1972-01-01

    Radiation Dosimetry, Supplement 1: Topics in Radiation Dosimetry covers instruments and techniques in dealing with special dosimetry problems. The book discusses thermoluminescence dosimetry in archeological dating; dosimetric applications of track etching; vacuum chambers of radiation measurement. The text also describes wall-less detectors in microdosimetry; dosimetry of low-energy X-rays; and the theory and general applicability of the gamma-ray theory of track effects to various systems. Dose equivalent determinations in neutron fields by means of moderator techniques; as well as developm

  15. Monitoring of radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-01

    The guide specifies the requirements for the monitoring of radiation exposure in instances where radiation is used. In addition to workers, the guide covers students, apprentices and visitors. The guide shall also apply to exposure from natural radiation. However, the monitoring of radiation exposure in nuclear power plants is dealt with in YVL Guide 7.10 and 7.11. The guide defines the concepts relevant to the monitoring of radiation exposure and provides guidelines for determining the necessity of monitoring and subsequently arranging such in different operations. In addition, the guide specifies the criteria for the approval and regulatory control of the dosimetric service.

  16. Monitoring of radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-01

    The guide specifies the requirements for the monitoring of radiation exposure in instances where radiation is used. In addition to workers, the guide covers students, apprentices and visitors. The guide shall also apply to exposure from natural radiation. However, the monitoring of radiation exposure in nuclear power plants is dealt with in YVL Guide 7.10 and 7.11. The guide defines the concepts relevant to the monitoring of radiation exposure and provides guidelines for determining the necessity of monitoring and subsequently arranging such in different operations. In addition, the guide specifies the criteria for the approval and regulatory control of the dosimetric service.

  17. Radiation dose and cancer risk to out-of-field and partially in-field organs from radiotherapy for symptomatic vertebral hemangiomas

    Energy Technology Data Exchange (ETDEWEB)

    Mazonakis, Michalis, E-mail: mazonak@med.uoc.gr; Damilakis, John [Department of Medical Physics, Faculty of Medicine, University of Crete, P.O. Box 2208, Iraklion, Crete 71003 (Greece); Tzedakis, Antonis [Department of Medical Physics, University Hospital of Iraklion, Iraklion, Crete 71110 (Greece); Lyraraki, Efrossyni [Department of Radiotherapy and Oncology, University Hospital of Iraklion, Iraklion, Crete 71110 (Greece)

    2016-04-15

    Purpose: Vertebral hemangiomas (VHs) are the most common benign tumors of the spine that may cause bone resorption. Megavoltage irradiation is usually the treatment of choice for the management of symptomatic VHs. The current study was conducted to estimate the risk for carcinogenesis from radiotherapy of this benign disease on the basis of the calculated radiation doses to healthy organs. Methods: The Monte Carlo N-particle transport code was employed to simulate the irradiation with 6 MV x-rays of a VH presented in the cervical, upper thoracic, lower thoracic, and lumbar spine. The average radiation dose (D{sub av}) received by each critical organ located outside the primarily irradiated area was calculated. Three-dimensional treatment plans were also generated for the VHs occurring at the four different sites of the spinal cord based on patients’ computed tomography data. The organ equivalent dose (OED) to each radiosensitive structure, which was partly encompassed by the applied treatment fields, was calculated with the aid of differential dose–volume histograms. The D{sub av} and the OED values were combined with a linear-no-threshold model and a nonlinear mechanistic model, respectively, to estimate the organ-, age-, and gender-specific lifetime attributable risks (LARs) for cancer development. The estimated risks were compared with the respective nominal lifetime intrinsic risks (LIRs) for the unexposed population. Results: For a standard target dose of 34 Gy, the OED varied from 0.39–5.15 Gy by the organ of interest and the irradiation site. The D{sub av} range for the out-of-field organs was 4.9 × 10{sup −4} to 0.56 Gy. The LAR for the appearance of malignancies in the partially in-field organs after radiotherapy of male and female patients was (0.08%–1.8%) and (0.09%–1.9%), respectively. These risk values were 1.5–15.5 times lower when compared to the respective LIRs. The lifetime probability for out-of-field cancer induction in irradiated

  18. Biological improvement of radiation resistance

    Energy Technology Data Exchange (ETDEWEB)

    Chun, K. J.; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J

    2000-08-01

    To investigate the mechanisms of gene action related to the radiation resistance in microorganisms could be essentially helpful for the development of radiation protectants and hormeric effects of low dose radiation. This book described isolation of radiation-resistant microorganisms, induction of radiation-resistant and functionally improved mutants by gamma-ray radiation, cloning and analysis of the radiation resistance related genes and analysis of the expressed proteins of the radiation resistant related genes.

  19. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Mengüç, M Pinar

    2011-01-01

    Providing a comprehensive overview of the radiative behavior and properties of materials, the fifth edition of this classic textbook describes the physics of radiative heat transfer, development of relevant analysis methods, and associated mathematical and numerical techniques. Retaining the salient features and fundamental coverage that have made it popular, Thermal Radiation Heat Transfer, Fifth Edition has been carefully streamlined to omit superfluous material, yet enhanced to update information with extensive references. Includes four new chapters on Inverse Methods, Electromagnetic Theory, Scattering and Absorption by Particles, and Near-Field Radiative Transfer Keeping pace with significant developments, this book begins by addressing the radiative properties of blackbody and opaque materials, and how they are predicted using electromagnetic theory and obtained through measurements. It discusses radiative exchange in enclosures without any radiating medium between the surfaces-and where heat conduction...

  20. Radiation curing of epoxies

    Science.gov (United States)

    Dickson, Lawrence W.; Singh, Ajit

    The literature on radiation polymerization of epoxy compounds has been reviewed to assess the potential use of radiation for curing these industrially important monomers. Chemical curing of epoxies may proceed by either cationic or anionic mechanisms depending on the nature of the curing agent, but most epoxies polymerize by cationic mechanisms under the influence of high-energy radiation. Radiation-induced cationic polymerization of epoxy compounds is inhibited by trace quantities of water because of proton transfer from the chain-propagating epoxy cation to water. Several different methods with potential for obtaining high molecular weight polymers by curing epoxies with high-energy radiation have been studied. Polymeric products with epoxy-like properties have been produced by radiation curing of epoxy oligomers with terminal acrylate groups and mixtures of epoxies with vinyl monomers. Both of these types of resin have good potential for industrial-scale curing by radiation treatment.

  1. Acute radiation syndrome and chronic radiation syndrome.

    Science.gov (United States)

    Grammaticos, Philip; Giannoula, Evanthia; Fountos, George P

    2013-01-01

    Acute radiation syndrome (ARS) or sickness or poisoning or toxicity is induced after a whole body exposure of men to high doses of radiation between 1-12Gy. First symptoms are from the gastrointestinal system, which together with bone marrow are the most sensitive parts of our body. Chronic radiation syndrome (CRS) may be induced by smaller than 1Gy radiation doses or after a mild form of ARS. Prophylaxis and treatment suggestions are described. In cases of ARS, a large part of the exposed population after proper medical care may survive, while without medical care this part of the population will be lost. Prophylaxis may also save another part of the population.

  2. Radiation processing of polyethylene

    Science.gov (United States)

    Barlow, A.; Biggs, J. W.; Meeks, L. A.

    This paper covers two areas (a) the use of high energy radiation for the synthesis and improvement of polymer properties and (b) the formulation of radiation curable compounds for automotive/appliance wire applications and high voltage insulation. The first part discusses the use of gamma radiation for the bulk polymerization of ethylene and the properties of the polymer produced. The use of low dose radiation to increase polymer molecular weight and modify polydispersity is also described together with its projected operational cost. An update is provided of the cost savings that can be realized when using radiation crosslinked heavy duty film, which expands its applications, compared with noncrosslinked materials. The second section of the paper considers the advantages and disadvantages of radiation vs. peroxide curing of wire and cable compounds. The formulation of a radiation curable, automotive/appliance wire compound is discussed together with the interactions between the various ingredients; i.e., base resin, antioxidants, flame retardant filler, coupling agents, processing aids and radiation to achieve the desired product. In addition, the general property requirements of a radiation curable polyethylene for high voltage insulation are discussed; these include crosslinking efficiency, thermal stability, wet tree resistance and satisfactory dielectric properties. Preliminary data generated in the development of a 230KV radiation crosslinked polyethylene insulation are included.

  3. Radiation physics, biophysics, and radiation biology

    Energy Technology Data Exchange (ETDEWEB)

    Hall, E.J.; Zaider, M.

    1993-05-01

    Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

  4. Theory of edge radiation

    CERN Document Server

    Geloni, Gianluca; Saldin, Evgeni; Schneidmiller, Evgeni; Yurkov, Mikhail

    2008-01-01

    We formulate a complete theory of Edge Radiation based on a novel method relying on Fourier Optics techniques. Similar types of radiation like Transition Undulator Radiation are addressed in the framework of the same formalism. Special attention is payed in discussing the validity of approximations upon which the theory is built. Our study makes consistent use of both similarity techniques and comparisons with numerical results from simulation. We discuss both near and far zone. Physical understanding of many asymptotes is discussed. Based on the solution of the field equation with a tensor Green's function technique, we also discuss an analytical model to describe the presence of a vacuum chamber. In particular, explicit calculations for a circular vacuum chamber are reported. Finally, we consider the use of Edge Radiation as a tool for electron beam diagnostics. We discuss Coherent Edge Radiation, Extraction of Edge Radiation by a mirror, and other issues becoming important at high electron energy and long ...

  5. Radiation processes in astrophysics

    CERN Document Server

    Tucker, Wallace H

    1975-01-01

    The purpose of this book is twofold: to provide a brief, simple introduction to the theory of radiation and its application in astrophysics and to serve as a reference manual for researchers. The first part of the book consists of a discussion of the basic formulas and concepts that underlie the classical and quantum descriptions of radiation processes. The rest of the book is concerned with applications. The spirit of the discussion is to present simple derivations that will provide some insight into the basic physics involved and then to state the exact results in a form useful for applications. The reader is referred to the original literature and to reviews for rigorous derivations.The wide range of topics covered is illustrated by the following table of contents: Basic Formulas for Classical Radiation Processes; Basic Formulas for Quantum Radiation Processes; Cyclotron and Synchrotron Radiation; Electron Scattering; Bremsstrahlung and Collision Losses; Radiative Recombination; The Photoelectric Effect; a...

  6. Solar radiation models - review

    Directory of Open Access Journals (Sweden)

    M. Jamil Ahmad, G.N. Tiwari

    2010-05-01

    Full Text Available In the design and study of solar energy, information on solar radiation and its components at a given location is very essential. Solar radiation data are required by solar engineers, architects, agriculturists and hydrologists for many applications such as solar heating, cooking, drying and interior illumination of buildings. For this purpose, in the past, several empirical correlations have been developed in order to estimate the solar radiation around the world. The main objective of this study is to review the global solar radiation models available in the literature. There are several formulae which relate global radiation to other climatic parameters such as sunshine hours, relative humidity and maximum temperature. The most commonly used parameter for estimating global solar radiation is sunshine duration. Sunshine duration can be easily and reliably measured and data are widely available.

  7. RHOBOT: Radiation hardened robotics

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, P.C.; Posey, L.D. [Sandia National Labs., Albuquerque, NM (United States)

    1997-10-01

    A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program.

  8. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  9. Transgenerational Radiation Epigenetics

    Science.gov (United States)

    2014-11-01

    showed altered expression in normal lung from F3 mice. Thus, traces of the effects of a single dose of radiation during development persist into...radiation showed a loss of global cytosine methylation in DNA from thymus , implicating profound epigenetic dysregulation (Tawa et al., 1998; Pogribny...for the carcinogenic and transgenerational effects of radiation. It is also anticipated that these epigenetic signatures will be developed as

  10. Radiation | Smokefree.gov

    Science.gov (United States)

    About half of all cancer patients get radiation therapy. This treatment can damage healthy cells, which can cause uncomfortable side effects. Use this action deck to get information on common symptoms that affect people going through radiation and learn how to manage them. The side effects of radiation may depend on the part of your body being treated. If you don’t see the symptom cards that describe what you are going through, try building your own deck.

  11. Radiation hormesis in plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Sung; Song, Hi Sup; Lee, Young Keun; Lee, Byung Hun; Shin, In Chul; Lim, Young Taek

    2000-04-01

    This research was performed to investigate the effects of low dose {gamma}-ray radiation on the seed germination and the following physiological responses in vegetable crops. Special attention was focused on whether the resistance of vegetables against the unfavorable conditions of environment such as subsequent high doses of radiation or Phytophthora blight of pepper could be enhanced as an aspect of radiation hormesis. Analysis and characterization of antioxidant enzyme from plant culture cells and radiation tolerant of transformed plants from antioxidant (POD) were accomplished in the plant irradiated with different dose of {gamma}-ray. (author)

  12. Potential theory of radiation

    Science.gov (United States)

    Chiu, Huei-Huang

    1989-01-01

    A theoretical method is being developed by which the structure of a radiation field can be predicted by a radiation potential theory, similar to a classical potential theory. The introduction of a scalar potential is justified on the grounds that the spectral intensity vector is irrotational. The vector is also solenoidal in the limits of a radiation field in complete radiative equilibrium or in a vacuum. This method provides an exact, elliptic type equation that will upgrade the accuracy and the efficiency of the current CFD programs required for the prediction of radiation and flow fields. A number of interesting results emerge from the present study. First, a steady state radiation field exhibits an optically modulated inverse square law distribution character. Secondly, the unsteady radiation field is structured with two conjugate scalar potentials. Each is governed by a Klein-Gordon equation with a frictional force and a restoring force. This steady potential field structure and the propagation of radiation potentials are consistent with the well known results of classical electromagnetic theory. The extension of the radiation potential theory for spray combustion and hypersonic flow is also recommended.

  13. [Thyroid and radiation].

    Science.gov (United States)

    Yamashita, S; Namba, H; Nagataki, S

    1993-11-20

    The topic "Thyroid and Radiation" is both an old and a new area to be solved by human beings. The thyroid is an organ that is usually susceptible to exposure to ionizing radiation, both by virtue of its ability to concentrate radioiodine (internal radiation) and by routine medical examination: Chest X-ray, Dental X-ray, X-irradiation of cervical lymphnodes etc. (external radiation). Iodine-131 is widely used for the therapy of Graves' disease and thyroid cancers, of which the disadvantage is radiation-induced hypothyroidism but not complications of thyroid tumor. The thyroid gland is comparatively radioresistant, however, the data obtained from Hiroshima, Nagasaki and Marshall islands indicates a high incidence of external radiation-induced thyroid tumors as well as hypothyroidism. The different biological effects of internal and external radiation remains to be further clarified. Interestingly, recent reports demonstrate the increased number of thyroid cancer in children around Chernobyl in Belarus. In this review, we would like to introduce the effect of radiation on the thyroid gland at the molecular, cellular and tissue levels. Furthermore the clinical usefulness of iodine-131, including the safety-control for radiation exposure will be discussed.

  14. Radiation`96. Conference handbook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    The conference program includes eight invited lectures which cover a range of contemporary topics in radiation science and technology. In addition, thirty-two oral papers were presented, along with forty-five posters. The conference handbook contains one-page precis or extended abstracts of all presentations, and is a substantial compendium of current radiation research in Australia.

  15. ALICE HMPID Radiator Vessel

    CERN Multimedia

    2003-01-01

    View of the radiator vessels of the ALICE/HMPID mounted on the support frame. Each HMPID module is equipped with 3 indipendent radiator vessels made out of neoceram and fused silica (quartz) windows glued together. The spacers inside the vessel are needed to stand the hydrostatic pressure. http://alice-hmpid.web.cern.ch/alice-hmpid

  16. Radiation belts of jupiter.

    Science.gov (United States)

    Stansberry, K G; White, R S

    1973-12-07

    Predictions of Jupiter's electron and proton radiation belts are based mainly on decimeter observations of 1966 and 1968. Extensive calculations modeling radial diffusion of particles inward from the solar wind and electron synchrotron radiation are used to relate the predictions and observations.

  17. Theory of edge radiation

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, G.; Kocharyan, V.; Saldin, E.; Schneidmiller, E.; Yurkov, M.

    2008-08-15

    We formulate a complete theory of Edge Radiation based on a novel method relying on Fourier Optics techniques. Similar types of radiation like Transition UndulatorRadiation are addressed in the framework of the same formalism. Special attention is payed in discussing the validity of approximations upon which the theory is built. Our study makes consistent use of both similarity techniques and comparisons with numerical results from simulation. We discuss both near and far zone. Physical understanding of many asymptotes is discussed. Based on the solution of the field equation with a tensor Green's function technique, we also discuss an analytical model to describe the presence of a vacuum chamber. In particular, explicit calculations for a circular vacuum chamber are reported. Finally, we consider the use of Edge Radiation as a tool for electron beam diagnostics. We discuss Coherent Edge Radiation, Extraction of Edge Radiation by a mirror, and other issues becoming important at high electron energy and long radiation wavelength. Based on this work we also study the impact of Edge Radiation on XFEL setups and we discuss recent results. (orig.)

  18. Radiation Exposure and Pregnancy

    Science.gov (United States)

    ... radiation (absorbed dose) or to the potential biological effect in tissue exposed to radiation (equivalent dose). Sv or Sievert The International System of Units (SI) unit for dose equivalent equal to 1 joule/kilogram. The sievert has replaced the rem; one ...

  19. NASA's Space Radiation Laboratory

    Institute of Scientific and Technical Information of China (English)

    Shelley Canright; 陈功

    2004-01-01

    @@ Imagine a human spacecraft crew voyaging through space. A satellite sends a warning; energetic particles are being accelerated from the Sun's corona①,sending dangerous radiation toward the spacecraft, but the crewmembers aren't worried. Long before their journey, researchers on Earth conducted experiments to accurately measure the hazards of space radiation and developed new materials and countermeasures to protect them.

  20. Radiation Therapy for Cancer

    Science.gov (United States)

    ... basic unit of light and other forms of electromagnetic radiation . It can be thought of as a bundle ... 3D-CRT uses very sophisticated computer software and advanced treatment machines to deliver radiation to very precisely shaped target areas. Many other ...

  1. New sources of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Schimmerling, W.

    1979-09-01

    An attempt is made to select examples of radiation sources whose application may make new or unconventional demands on radiation protection and dosimetry. A substantial body of knowledge about high energy facilities exists and, partly for this reason, the great high energy accelerators are mentioned only briefly.

  2. Electronics for radiation detection

    CERN Document Server

    2011-01-01

    Addresses the developments in the design of semiconductor detectors and integrated circuits, in the context of medical imaging using ionizing radiation. This book explains how circuits for radiation are built, focusing on practical information about how they are being used, rather than mathematical details.

  3. Instrument for assaying radiation

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Jody Rustyn; Farfan, Eduardo B.

    2016-03-22

    An instrument for assaying radiation includes a flat panel detector having a first side opposed to a second side. A collimated aperture covers at least a portion of the first side of the flat panel detector. At least one of a display screen or a radiation shield may cover at least a portion of the second side of the flat panel detector.

  4. Semiconductor radiation detection systems

    CERN Document Server

    2010-01-01

    Covers research in semiconductor detector and integrated circuit design in the context of medical imaging using ionizing radiation. This book explores other applications of semiconductor radiation detection systems in security applications such as luggage scanning, dirty bomb detection and border control.

  5. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  6. [Radiation induced tumors].

    Science.gov (United States)

    Gutiérrez Bayard, L; Delgado López, L; Tirado Bejarano, C; Gómez Puerto, A; García Fernández, J L

    1998-04-01

    Radiations at cellular level produce different effects, depending on type of radiation and irradiated tissue. The radiation-induced cancers are associated to non-letals genetics mutations, and to classify like radiation induced tumors is necessary that appear in the treatment volume, a long latency period (years), histolo-different to the primary lesion, enough doses quantitatively and that exists a greater incidence in the irradiated populations. The genetics mutations affect at tumoral suppressors gen(Gen RB I, p53, BRCA I, BRCA 2) and repressors gen (hMSH 2, hMLH I,...), they could be longer and multifocals mutations, and produce lack of cellular control and a greater predisposition to develop tumors and a probable risk of increment of radiosensitivity. We present some of the more representatives studies about radiation-induced tumors.

  7. Fundamentals of Radiation Dosimetry

    Science.gov (United States)

    Bos, Adrie J. J.

    2011-05-01

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  8. Transition radiation by neutrinos

    Energy Technology Data Exchange (ETDEWEB)

    Ioannisian, A.N., E-mail: ara.ioannisyan@cern.ch [Yerevan Physics Institute, Alikhanian Br. 2, 375036 Yerevan (Armenia); CERN, Theory Division, CH-1211 Geneva 23 (Switzerland); Institute for Theoretical Physics and Modeling, 375036 Yerevan (Armenia); Ioannisian, D.A. [Yerevan Physics Institute, Alikhanian Br. 2, 375036 Yerevan (Armenia); Institute for Theoretical Physics and Modeling, 375036 Yerevan (Armenia); Physics Department, Yerevan State University, 1 Alex Manoogian (Armenia); Kazarian, N.A. [Institute for Theoretical Physics and Modeling, 375036 Yerevan (Armenia)

    2011-08-19

    We calculate the transition radiation process {nu}{yields}{nu}{gamma} at an interface of two media. The neutrinos are taken to be with only standard-model couplings. The medium fulfills the dual purpose of inducing an effective neutrino-photon vertex and of modifying the photon dispersion relation. The transition radiation occurs when at least one of those quantities have different values in different media. The neutrino mass is ignored due to its negligible contribution. We present a result for the probability of the transition radiation which is both accurate and analytic. For E{sub {nu}=}1 MeV neutrino crossing polyethylene-vacuum interface the transition radiation probability is about 10{sup -39} and the energy intensity is about 10{sup -34} eV. At the surface of the neutron stars the transition radiation probability may be {approx}10{sup -20}. Our result is by the three orders of magnitude larger than those of previous calculations.

  9. Transition radiation by neutrinos

    Science.gov (United States)

    Ioannisian, A. N.; Ioannisian, D. A.; Kazarian, N. A.

    2011-08-01

    We calculate the transition radiation process ν→νγ at an interface of two media. The neutrinos are taken to be with only standard-model couplings. The medium fulfills the dual purpose of inducing an effective neutrino-photon vertex and of modifying the photon dispersion relation. The transition radiation occurs when at least one of those quantities have different values in different media. The neutrino mass is ignored due to its negligible contribution. We present a result for the probability of the transition radiation which is both accurate and analytic. For Eν=1 MeV neutrino crossing polyethylene-vacuum interface the transition radiation probability is about 10 and the energy intensity is about 10 eV. At the surface of the neutron stars the transition radiation probability may be ˜10. Our result is by the three orders of magnitude larger than those of previous calculations.

  10. Electrodynamics of Radiating Charges

    Directory of Open Access Journals (Sweden)

    Øyvind Grøn

    2012-01-01

    Full Text Available The theory of electrodynamics of radiating charges is reviewed with special emphasis on the role of the Schott energy for the conservation of energy for a charge and its electromagnetic field. It is made clear that the existence of radiation from a charge is not invariant against a transformation between two reference frames that has an accelerated motion relative to each other. The questions whether the existence of radiation from a uniformly accelerated charge with vanishing radiation reaction force is in conflict with the principle of equivalence and whether a freely falling charge radiates are reviewed. It is shown that the resolution of an electromagnetic “perpetuum mobile paradox” associated with a charge moving geodetically along a circular path in the Schwarzschild spacetime requires the so-called tail terms in the equation of motion of a charged particle.

  11. Fading Hawking Radiation

    CERN Document Server

    Sakalli, I; Pasaoglu, H

    2012-01-01

    In this study, we explore a particular type Hawking radiation which ends with zero temperature and entropy. The appropriate black holes for this purpose are the linear dilaton black holes. In addition to the black hole choice, a recent formalism in which the Parikh-Wilczek's tunneling formalism amalgamated with quantum corrections to all orders in \\hbar is considered. The adjustment of the coefficients of the quantum corrections plays a crucial role on this particular Hawking radiation. The obtained tunneling rate indicates that the radiation is not pure thermal anymore, and hence correlations of outgoing quanta are capable of carrying away information encoded within them. Finally, we show in detail that when the linear dilaton black hole completely evaporates through such a particular radiation, entropy of the radiation becomes identical with the entropy of the black hole, which corresponds to "no information loss".

  12. Accelerator and radiation physics

    CERN Document Server

    Basu, Samita; Nandy, Maitreyee

    2013-01-01

    "Accelerator and radiation physics" encompasses radiation shielding design and strategies for hadron therapy accelerators, neutron facilities and laser based accelerators. A fascinating article describes detailed transport theory and its application to radiation transport. Detailed information on planning and design of a very high energy proton accelerator can be obtained from the article on radiological safety of J-PARC. Besides safety for proton accelerators, the book provides information on radiological safety issues for electron synchrotron and prevention and preparedness for radiological emergencies. Different methods for neutron dosimetry including LET based monitoring, time of flight spectrometry, track detectors are documented alongwith newly measured experimental data on radiation interaction with dyes, polymers, bones and other materials. Design of deuteron accelerator, shielding in beam line hutches in synchrotron and 14 MeV neutron generator, various radiation detection methods, their characteriza...

  13. Applications of ionizing radiations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    Developments in standard applications and brand new nuclear technologies, with high impact on the future of the agriculture, medicine, industry and the environmental preservation. The Radiation Technology Center (CTR) mission is to apply the radiation and radioisotope technologies in Industry, Health, Agriculture, and Environmental Protection, expanding the scientific knowledge, improving human power resources, transferring technology, generating products and offering services for the Brazilian society. The CTR main R and D activities are in consonance with the IPEN Director Plan (2011-2013) and the Applications of Ionizing Radiation Program, with four subprograms: Irradiation of Food and Agricultural Products; Radiation and Radioisotopes Applications in Industry and Environment; Radioactive Sources and Radiation Applications in Human Health; and Radioactive Facilities and Equipment for the Applications of Nuclear Techniques.

  14. Radiation Therapy for Lung Cancer

    Science.gov (United States)

    ... of the lung cancer and your overall health. Radiation Therapy Radiation is a high-energy X-ray that can ... surgery, chemotherapy or both depending upon the circumstances. Radiation therapy works within cancer cells by damaging their ...

  15. Radiation vulcanization of rubbers

    Energy Technology Data Exchange (ETDEWEB)

    Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2002-02-01

    An abstract of the radiation process of polymer materials and the polymer reaction by radiation is explained. Main radiation is 250 keV to 10 MeV of electron rays in the industry. Radiation cross-linked rubber has less the tensile strength than that by sulfur and organic peroxide crosslinking. The main origins of low tensile strength are caused by cut of backbone chain and ozone depend on radiation. Acceleration of crosslinking and short time of radiation are necessary to improve these defects. To accelerate crosslinking, we used crosslinking accelerators, for example, three poly-functional monomers (PFM). The maximum tensile strength of styrene-butadiene rubber (SBR) not added crosslinking accelerators showed 3 MPa at 110 kGy, but SBR added A-TMMT (tetramethylolmethane tetraacrylate) showed 5.5 MPa at 110 kGy. Radiation crosslinking of many kinds of rubber: isoprene (IR), SBR, CR, nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), butyl rubber (IIR), chlorinated butyl rubber (CIIR), EPM and TPE are explained. (S.Y.)

  16. Depression and ionizing radiation.

    Science.gov (United States)

    Loganovsky, K N; Vasilenko, Z L

    2013-01-01

    The objective of this at issue paper is the analysis of published data in correlation with the results of own research on the potential role of ionizing radiation in the genesis of depressive disorders. Depression is one of the most significant and long-term effect of the atomic bombings, nuclear testing and radiation emergences. The participants of the accident at the Chornobyl nuclear power plant increased prevalence of depression (18.0% and 13.1% in controls) and suicide rates. Depression is mainly observed in the structure of an organic mental disorder against cerebrovascular disease. The clinical pattern is dominated by asthenoadynamic and asthenoapathetic depression. Depressive disorders in radiation emergencies are multifactorial, that is the result of exposure to the complex psychogenic and radiological accident's factors, impact of traditional risk factors, somatic and neurological diseases, genetic predisposition, predisposition, etc. At the same time, exposure to ionizing radiation is a factor in the genesis of depression. This impact can be direct (to the Central Nervous System), and indirectly through the somatic and neurological abnormalities (multiorgan dysfunction) as well as by a variety of pathogenic mechanisms of ionizing radiation on the brain that have been discovered recently. It is strongly necessary analytical clinical and epidemiological studies with verification of depression and evidence-based establishment of the role of radiation and non-radiation risk factors. Loganovskyj K. N., Vasylenko Z. L., 2013.

  17. Beneficial uses of radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fox, M.R.

    1991-10-01

    An overall decline in technical literacy within the American public has come at a time when technological advances are accelerating in the United States and around the world. This had led to a large communication gulf between the general public and the technologists. Nowhere is this more evident then with the topic of radiation. Regrettably, too few people know about sources of radiation, the pervasiveness, amounts, and variabilities, and do not have a true understanding of the environment in which we live. Nor do many people know that radiation has been used in beneficial ways for decades around the world. While the general public does not know of the scientific applications to which radiation has been deployed, it nevertheless had benefited tremendously from these efforts. Thanks to the well know properties of radiation, scientific ingenuity has found many uses of radiation in chemical and agricultural research, biomedical research, in the diagnoses and treatment of hundreds of types of diseases, in industrial applications, food irradiation, and many others. This paper provides a sample of the types of uses to which radiation has been used to help advance the betterment of humankind.

  18. Biological Effects of Ionizing Radiation

    Science.gov (United States)

    Ingram, M.; Mason, W. B.; Whipple, G. H.; Howland, J. W.

    1952-04-07

    This report presents a review of present knowledge and concepts of the biological effects of ionizing radiations. Among the topics discussed are the physical and chemical effects of ionizing radiation on biological systems, morphological and physiological changes observed in biological systems subjected to ionizing radiations, physiological changes in the intact animal, latent changes following exposure of biological systems to ionizing radiations, factors influencing the biological response to ionizing radiation, relative effects of various ionizing radiations, and biological dosimetry.

  19. SYNCHROTRON RADIATION SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  20. Stimulated coherent transition radiation

    Energy Technology Data Exchange (ETDEWEB)

    Hung-chi Lihn

    1996-03-01

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed.

  1. The theory of heat radiation

    CERN Document Server

    Planck, Max

    2003-01-01

    Nobel laureate's classic exposition of the theory of radiant heat in terms of quantum action. Kirchoff's law, black radiation, Maxwell's radiation pressure, entropy, other topics. 1914 edition. Bibliography.

  2. Radiation Belt Dynamics

    Science.gov (United States)

    2015-12-27

    Wygant, J. R., et al., “The Electric Field and Waves Instruments on the Radiation Belt Storm Probes Mission,” Space Sci. Rev., 179, 2013, pp. 183–220, doi...A. N., Li, X., Kanekal, S. G., Hudson, M. K., and Kress, B. T., “Observations of the Inner Radiation Belt: CRAND and Trapped Solar Protons,” J...1215–1228, doi:10.1002/2014JA020777. [27] Selesnick, R. S., “ Measurement of Inner Radiation Belt Electrons with Kinetic Energy Above 1 MeV,” J

  3. Nuclear medicine radiation dosimetry

    CERN Document Server

    McParland, Brian J

    2010-01-01

    Complexities of the requirements for accurate radiation dosimetry evaluation in both diagnostic and therapeutic nuclear medicine (including PET) have grown over the past decade. This is due primarily to four factors: growing consideration of accurate patient-specific treatment planning for radionuclide therapy as a means of improving the therapeutic benefit, development of more realistic anthropomorphic phantoms and their use in estimating radiation transport and dosimetry in patients, design and use of advanced Monte Carlo algorithms in calculating the above-mentioned radiation transport and

  4. Radiation therapy physics

    CERN Document Server

    Hendee, William R; Hendee, Eric G

    2013-01-01

    The Third Edition of Radiation Therapy Physics addresses in concise fashion the fundamental diagnostic radiologic physics principles as well as their clinical implications. Along with coverage of the concepts and applications for the radiation treatment of cancer patients, the authors have included reviews of the most up-to-date instrumentation and critical historical links. The text includes coverage of imaging in therapy planning and surveillance, calibration protocols, and precision radiation therapy, as well as discussion of relevant regulation and compliance activities. It contains an upd

  5. Foundations of radiation hydrodynamics

    CERN Document Server

    Mihalas, Dimitri

    1999-01-01

    Radiation hydrodynamics is a broad subject that cuts across many disciplines in physics and astronomy: fluid dynamics, thermodynamics, statistical mechanics, kinetic theory, and radiative transfer, among others. The theory developed in this book by two specialists in the field can be applied to the study of such diverse astrophysical phenomena as stellar winds, supernova explosions, and the initial phases of cosmic expansion, as well as the physics of laser fusion and reentry vehicles. As such, it provides students with the basic tools for research on radiating flows.Largely self-contained,

  6. Radiation hormesis in plant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Sung; Song, Hi Sup; Lee, Young Keun; Cun, Ki Jung; Shin, In Chul; Lim, Young Taek

    1999-04-01

    This research was performed to investigate the effects of low dose {gamma}-ray radiation on the seed germination and the following physiological responses in vegetable crops. Special attention was focused on whether the resistance of vegetables against the unfavorable conditions of environment such as acid rain or soil types could be enhanced as an aspect of radiation hormesis. Analysis and characterization of antioxidant enzyme from plant culture cells and radiation tolerant of transformed plants from antioxidant enzyme (POD) were accomplished in the plant irradiated with difference dosage of {gamma}-ray.

  7. Ethics and radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Hansson, Sven Ove [Department of Philosophy and the History of Technology, Royal Institute of Technology (KTH), Teknikringen 78 B, 2tr, SE-100 44 Stockholm (Sweden)

    2007-06-01

    Some of the major problems in radiation protection are closely connected to issues that have a long, independent tradition in moral philosophy. This contribution focuses on two of these issues. One is the relationship between the protection of individuals and optimisation on the collective level, and the other is the relative valuation of future versus immediate damage. Some of the intellectual tools that have been developed by philosophers can be useful in radiation protection. On the other hand, philosophers have much to learn from radiation protectors, not least when it comes to finding pragmatic solutions to problems that may be intractable in principle.

  8. Synchrotron Radiation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Studies the effects of UV radiation and X rays on solids, and calibrates X-ray optics, detectors, and instruments.DESCRIPTION: Research focuses on applying...

  9. Intelligent Radiative Materials Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An opportunity to boost energy efficiency in homes and buildings exists through the design of functional radiative properties in glass and other building materials....

  10. Nanotechnology in radiation oncology.

    Science.gov (United States)

    Wang, Andrew Z; Tepper, Joel E

    2014-09-10

    Nanotechnology, the manipulation of matter on atomic and molecular scales, is a relatively new branch of science. It has already made a significant impact on clinical medicine, especially in oncology. Nanomaterial has several characteristics that are ideal for oncology applications, including preferential accumulation in tumors, low distribution in normal tissues, biodistribution, pharmacokinetics, and clearance, that differ from those of small molecules. Because these properties are also well suited for applications in radiation oncology, nanomaterials have been used in many different areas of radiation oncology for imaging and treatment planning, as well as for radiosensitization to improve the therapeutic ratio. In this article, we review the unique properties of nanomaterials that are favorable for oncology applications and examine the various applications of nanotechnology in radiation oncology. We also discuss the future directions of nanotechnology within the context of radiation oncology. © 2014 by American Society of Clinical Oncology.

  11. Physics for radiation protection

    CERN Document Server

    Martin, James E

    2013-01-01

    A much-needed working resource for health physicists and other radiation protection professionals, this volume presents clear, thorough, up-to-date explanations of the basic physics necessary to address real-world problems in radiation protection. Designed for readers with limited as well as basic science backgrounds, Physics for Radiation Protection emphasizes applied concepts and carefully illustrates all topics through examples as well as practice problems. Physics for Radiation Protection draws substantially on current resource data available for health physics use, providing decay schemes and emission energies for approximately 100 of the most common radionuclides encountered by practitioners. Excerpts of the Chart of the Nuclides, activation cross sections, fission yields, fission-product chains, photon attenuation coefficients, and nuclear masses are also provided.

  12. NASA Space Radiation Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory is a NASA funded facility, delivering heavy ion beams to a target area where scientists...

  13. Lecture on Thermal Radiation

    Science.gov (United States)

    Dennis, Brian R.

    2006-01-01

    This lecture will cover solar thermal radiation, particularly as it relates to the high energy solar processes that are the subject of this summer school. After a general review of thermal radiation from the Sun and a discussion of basic definitions, the various emission and absorption mechanisms will be described including black-body emission, bremsstrahlung, free-bound, and atomic line emissions of all kinds. The bulk of the time will be spent discussing the observational characteristics of thermal flare plasma and what can be learned about the flare energy release process from observations of the thermal radiation at all wavelengths. Information that has been learned about the morphology, temperature distribution, and composition of the flare plasma will be presented. The energetics of the thermal flare plasma will be discussed in relation to the nonthermal energy of the particles accelerated during the flare. This includes the total energy, the radiated and conductive cooling processes, and the total irradiated energy.

  14. Natural radiative cooling

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.

    1979-01-01

    Natural radiative cooling at night was measured based on the surface-radiation spectrum after the heat balance of the surface exposed to the sun had been reradiated. A concept equivalent to the sky temperature and a concept useful for obtaining the net heat flux are discussed. The highest possible equilibrium temperature of the selective surface can be lowered; however, how to apply this practically is not yet known. A simple radiator, completely enclosed by a transparent screen, can produce a significant and inexpensive cooling effect. The results of experiments carried out in an area such as Padua, Italy, where the climate is not suitable for cooling purposes can still be predicted theoretically. The possibility of using the collector for heat collection during the day and as a radiator at night is indicated.

  15. Radiation protection in medicine

    Energy Technology Data Exchange (ETDEWEB)

    Vano, E.; Holmberg, O.; Perez, M. R.; Ortiz, P.

    2016-08-01

    Diagnostic, interventional and therapeutic used of ionizing radiation are beneficial for hundreds of millions of people each year by improving health care and saving lives. In March 2001, the first International Conference on the Radiological Protection of Patients was held in Malaga, Spain, which led to an international action plan for the radiation protection of patients. Ten years after establishing the international action plan, the International Conference on Radiation Protection in Medicine: Setting the Scene for the Next Decade was held in Bonn, Germany, in December 2012. the main outcome of this conference was the so called Bonn Call for Action that identifies then priority actions to enhance radiation protection in medicine for the next decade. The IAEA and WHO are currently working in close cooperation to foster and support the implementation of these ten priority actions in Member States, but their implementation requires collaboration of national governments, international agencies, researchers, educators, institutions and professional associations. (Author)

  16. Radiation synovectomy revisited

    Energy Technology Data Exchange (ETDEWEB)

    Deutsch, E. (Mallinckrodt Medical, Inc., St. Louis, MO (United States)); Brodack, J.W. (Mallinckrodt Medical, Inc., St. Louis, MO (United States)); Deutsch, K.F. (Mallinckrodt Medical, Inc., St. Louis, MO (United States))

    1993-11-01

    Radiation synovectomy is a potential weapon in the therapeutic armamentarium of nuclear medicine. It is an attractive alternative to surgical or chemical synovectomy for the treatment of rheumatoid arthritis. In this article the clinical results obtained with radiation synovectomy from the 1950s through 1992 are summarized and reviewed. Even after taking into account the paucity of well-controlled trials and rigorous clinical follow-up, it is clear that radiation synovectomy is efficacious in controlling the symptoms of rheumatoid arthritis. However, the procedure is not widely used because of concerns about leakage of radioactivity from the treated joint, and the resulting high doses that can be delivated to nontarget organs. New approaches to the preparation of radiolabeled particles for use in radiation synovectomy promise to minimize this leakage and thus allows the full potential of this important radiotherapy to be realized. (orig.)

  17. Radioactivity, radionuclides, radiation

    CERN Document Server

    Magill, Joseph

    2005-01-01

    RADIOACTIVITY – RADIONUCLIDES – RADIATION is suitable for a general audience interested in topical environmental and human health radiological issues such as radiation exposure in aircraft, food sterilisation, nuclear medicine, radon gas, radiation dispersion devices ("dirty bombs")… It leads the interested reader through the three Rs of nuclear science, to the forefront of research and developments in the field. The book is also suitable for students and professionals in the related disciplines of nuclear and radiochemistry, health physics, environmental sciences, nuclear and astrophysics. Recent developments in the areas of exotic decay modes (bound beta decay of ‘bare’ or fully ionized nuclei), laser transmutation, nuclear forensics, radiation hormesis and the LNT hypothesis are covered. Atomic mass data for over 3000 nuclides from the most recent (2003) evaluation are included.

  18. Radiation incidents in dentistry

    Energy Technology Data Exchange (ETDEWEB)

    Lovelock, D.J. [Dental Hospital and School, Newcastle upon Tyne (United Kingdom). Dept. of Radiology

    1996-12-31

    Most dental practitioners act as their own radiographer and radiologist, unlike their medical colleagues. Virtually all dental surgeons have a dental X-ray machine for intraoral radiography available to them and 40% of dental practices have equipment for dental panoramic tomography. Because of the low energy of X-ray equipment used in dentistry, radiation incidents tend to be less serious than those associated with other aspects of patient care. Details of 47 known incidents are given. The advent of the 1985 and 1988 Ionising Radiation Regulations has made dental surgeons more aware of the hazards of radiation. These regulations, and general health and safety legislation, have led to a few dental surgeons facing legal action. Because of the publicity associated with these court cases, it is expected that there will be a decrease in radiation incidents arising from the practice of dentistry. (author).

  19. Blackbody Radiation Tables

    Science.gov (United States)

    at the indicated wavelength and temperature, Planck’s equation. This equation represents the monochromatic radiant intensity at a particular wavelength from a perfect radiator maintained at the indicated temperature.

  20. Radiation Therapy (For Parents)

    Science.gov (United States)

    ... with ink to highlight the treatment area. This "tattoo" should not be wiped off because it helps ... quickly to reduce exposure. previous continue Common Side Effects of Radiation If your child has cancer, you' ...

  1. Radiative heat transfer

    CERN Document Server

    Modest, Michael F

    2013-01-01

    The third edition of Radiative Heat Transfer describes the basic physics of radiation heat transfer. The book provides models, methodologies, and calculations essential in solving research problems in a variety of industries, including solar and nuclear energy, nanotechnology, biomedical, and environmental. Every chapter of Radiative Heat Transfer offers uncluttered nomenclature, numerous worked examples, and a large number of problems-many based on real world situations-making it ideal for classroom use as well as for self-study. The book's 24 chapters cover the four major areas in the field: surface properties; surface transport; properties of participating media; and transfer through participating media. Within each chapter, all analytical methods are developed in substantial detail, and a number of examples show how the developed relations may be applied to practical problems. It is an extensive solution manual for adopting instructors. Features: most complete text in the field of radiative heat transfer;...

  2. Radiation Protection Group

    CERN Multimedia

    2006-01-01

    The Radioactive Waste Section of the Radiation Protection Group wishes to inform you that the Radioactive Waste Treatment Centre will be closed on the afternoon of Tuesday 19 December 2006. Thank-you for your understanding.

  3. Radiation practices 1996

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.

    1997-05-01

    At the end of 1996, there were 1,762 valid safety licences in Finland for the use of radiation. In addition, there were 2,052 responsible parties for dental x-ray diagnostics. The registry of the Finnish Centre for Radiation and Nuclear Safety listed 13,360 radiation sources and 313 radionuclide laboratories. The import of radioactive substances amounted to 1.14 x 10{sup +16} Bq and export to 7.78 x 10{sup +13} Bq. A total of 4.02 x 10{sup +13} Bq of short-lived radionuclides were produced in Finland. There were 11,842 workers monitored for radiation exposure at 1,352 work sites. Of these employees, 27% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of individual dosimeter readings) was 7.96 manSv in 1996, with nuclear power plant workers accounting for 69% of this total. The annual dosimeter reading of ten medical doctors (radiologists, interventional radiologists and cardiologists) and eight nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of dosimeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 242 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations where unusually high exposure to radiation was an unavoidable part of the task. Report was made of 12 incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Five of these cases occurred in radiotherapy, three in use of a radiation source in industry, three in transport of radiation sources and one in use of solarium appliances. Radiation-contaminated material was found in 17 shipments of scrap. (orig.)

  4. Radiation therapy physics

    CERN Document Server

    1995-01-01

    The aim of this book is to provide a uniquely comprehensive source of information on the entire field of radiation therapy physics. The very significant advances in imaging, computational, and accelerator technologies receive full consideration, as do such topics as the dosimetry of radiolabeled antibodies and dose calculation models. The scope of the book and the expertise of the authors make it essential reading for interested physicians and physicists and for radiation dosimetrists.

  5. Radiative transfer dynamo effect

    Science.gov (United States)

    Munirov, Vadim R.; Fisch, Nathaniel J.

    2017-01-01

    Magnetic fields in rotating and radiating astrophysical plasma can be produced due to a radiative interaction between plasma layers moving relative to each other. The efficiency of current drive, and with it the associated dynamo effect, is considered in a number of limits. It is shown here, however, that predictions for these generated magnetic fields can be significantly higher when kinetic effects, previously neglected, are taken into account.

  6. Auditing radiation sterilization facilities

    Science.gov (United States)

    Beck, Jeffrey A.

    The diversity of radiation sterilization systems available today places renewed emphasis on the need for thorough Quality Assurance audits of these facilities. Evaluating compliance with Good Manufacturing Practices is an obvious requirement, but an effective audit must also evaluate installation and performance qualification programs (validation_, and process control and monitoring procedures in detail. The present paper describes general standards that radiation sterilization operations should meet in each of these key areas, and provides basic guidance for conducting QA audits of these facilities.

  7. Acute local radiation injuries

    Energy Technology Data Exchange (ETDEWEB)

    Gongora, R. (Institut Curie, 75 - Paris (France)); Jammet, H. (Commissariat a l' Energie Atomique, ISPN, 92 - Fontenay-aux-Roses (France))

    1983-01-01

    Local acute radiation injuries do not occur very often. Their origin is generally accidental. They show specific anatomo-clinical features. The clinical evolution and therapeutic behaviour are dependent on the dose level and topographical distribution. The dosimetric assessment requires physical methods and paraclinical investigations. From a study of 60 cases followed by the International Center of Radiopathology, the clinical symptomatology is described and the problems raised to the radiopathologist physician by local acute radiation injuries are stated.

  8. Radiation technology in Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Vo Van Thuan [Institute for Nuclear Science and Technique, VAEC, Hanoi (Viet Nam)

    2001-03-01

    Most of researches and developments in the field of radiation technology that have completed in a decade before 1995 were concentrated to sterilization and food irradiation. A series of medical devices and products were the main commodities for research and application trials. Also, many kind of food have attracted the scientists and technologists to investigate the application and commercialization of irradiated food. In addition, the radiation technology also was utilized for processing of non-food items including herbs, medicinal produces, and tobacco material. Since 1996 VAEC and INST has realized the important role of radiation processing on natural polymers. Hence, along with the commercialization of radiation technology, three research teams were established for the target. This report reviews the recent activities and achievements on radiation technology in the country emphasizing on the radiation processing of polysaccharides. A number of polysaccharides, which originated from bio-/agro-wastes such as seaweed, shrimp shells, lignocelluloses, was modified or degraded by irradiation to prepare hydrogel and bio-active material using for health-care and crop production. (author)

  9. Radiation analysis devices, radiation analysis methods, and articles of manufacture

    Science.gov (United States)

    Roybal, Lyle Gene

    2010-06-08

    Radiation analysis devices include circuitry configured to determine respective radiation count data for a plurality of sections of an area of interest and combine the radiation count data of individual of sections to determine whether a selected radioactive material is present in the area of interest. An amount of the radiation count data for an individual section is insufficient to determine whether the selected radioactive material is present in the individual section. An article of manufacture includes media comprising programming configured to cause processing circuitry to perform processing comprising determining one or more correction factors based on a calibration of a radiation analysis device, measuring radiation received by the radiation analysis device using the one or more correction factors, and presenting information relating to an amount of radiation measured by the radiation analysis device having one of a plurality of specified radiation energy levels of a range of interest.

  10. Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles

    Directory of Open Access Journals (Sweden)

    Dörr Harald

    2011-11-01

    Full Text Available Abstract Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

  11. Gravitational radiation resistance, radiation damping and field fluctuations

    Science.gov (United States)

    Schaefer, G.

    1981-03-01

    Application is made of two different generalized fluctuation-dissipation theorems and their derivations to the calculation of the gravitational quadrupole radiation resistance using the radiation-reaction force given by Misner, Thorne and Wheeler and the usual tidal force on one hand and the tidal force and the free gravitational radiation field on the other hand. The quantum-mechanical version (including thermal generalizations) of the well known classical quadrupole radiation damping formula is obtained as a function of the radiation resistance.

  12. Radiation practices 1997

    Energy Technology Data Exchange (ETDEWEB)

    Havukainen, R. [ed.

    1998-05-01

    At the end of 1997, there were 1,753 valid safety licenses in Finland for the use of radiation. In addition, there were 2,065 responsible parties for dental x-ray diagnostics. The registry of STUK - Radiation and Nuclear Safety Authority listed 13,839 radiation sources and 302 radionuclide laboratories. The import of radioactive substances amounted to 1.09 x 10{sup +16} Bq and export to 2.4 x 10{sup +13} Bq. Short-lived radionuclides produced in Finland amounted to 5.2 x 10{sup +13} Bq. There were 11,773 workers monitored for radiation exposure at 1,316 work sites. Of these employees, 24% received an annual dose exceeding the recording level. The total dose recorded in the dose registry (sum of the individual dosemeter readings) was 6.6 Sv in 1997, with nuclear power plant workers accounting for 62% of this total. The annual dosemeter reading of thirteen medical doctors (radiologists, interventional radiologists and cardiologists) and six nuclear power plant employees was equal to or in excess of 20 mSv. Effective doses, however, did not exceed the dose limit of 50 mSv established for one-year monitoring periods. The sum of the dosemeter readings (depth dose) on the lead-rubber apron of one interventional radiologist was 253 mSv. It was verified that the annual dose limit for the lens of the eye, 150 mSv, had been exceeded in this case. This high dose was caused by the fact that the radiologist had carried out multiple examinations in which unusually high exposure to radiation was an unavoidable part of the task. Reports were made of four incidents of anomalies in the use of radiation. None of these proved to have caused significant radiation exposure to the radiation source operators. Two of these cases occurred in the medical use of radiation, one in the use of radiation sources in industry, and one in the use of solarium appliances. (orig.)

  13. Radiation nephritis causing nephrotic syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Jennette, J.C.; Ordonez, N.G.

    1983-12-01

    Clinical symptoms of acute radiation nephritis with nephrotic syndrome developed in a fifty-six-year-old woman after abdominal radiation therapy for an astrocytoma of the spinal cord. The diagnosis of radiation nephritis was confirmed by renal biopsy. To our knowledge, this is the first documented case of radiation nephritis associated with nephrotic syndrome.

  14. Radiation Sensitization in Cancer Therapy.

    Science.gov (United States)

    Greenstock, Clive L.

    1981-01-01

    Discusses various aspects of radiation damage to biological material, including free radical mechanisms, radiation sensitization and protection, tumor hypoxia, mechanism of hypoxic cell radiosensitization, redox model for radiation modification, sensitizer probes of cellular radiation targets, pulse radiolysis studies of free radical kinetics,…

  15. Proposing a simple radiation scale for the public: Radiation index

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Gyu Seong; Kim, Jong Hyun [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of); Park, Tae Soon [Center for Ionizing Radiation, Korea Research Institute of Standards and Science (KRISS), Daejeon (Korea, Republic of); Cho, Kunwoo [Dept. of Natural Radiation Safety, Korea Institute of Nuclear Safety (KINS), Daejeon (Korea, Republic of)

    2017-04-15

    A new radiation scale is proposed. With empathy toward the vast majority of people who are not well versed in radiation and related matters, and thus suffering from misunderstanding that breeds unnecessary fear of radiation, the aim of proposing a new radiation scale, radiation index (RAIN), is to put the general public at ease with the concept of radiation. RAIN is defined in dimensionless numbers that relate any specific radiation dose to a properly defined reference level. As RAIN is expressed in plain numbers without an attached scientific unit, the public will feel comfortable with its friendly look, which in turn should help them understand radiation dose levels easily and allay their anxieties about radiation. The expanded awareness and proper understanding of radiation will empower the public to feel that they are not hopeless victims of radiation. The correspondence between RAIN and the specific accumulated dose is established. The equivalence will allow RAIN to serve as a common language of communication for the general public with which they can converse with radiation experts to discuss matters related to radiation safety, radiation diagnosis and therapy, nuclear accidents, and other related matters. Such fruitful dialogues will ultimately enhance public acceptance of radiation and associated technologies.

  16. Radiation in Particle Simulations

    Energy Technology Data Exchange (ETDEWEB)

    More, R; Graziani, F; Glosli, J; Surh, M

    2010-11-19

    Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of megabars to thousands of gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present four methods that attempt a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The first method applies the Lienard-Weichert solution of Maxwell's equations for a classical particle whose motion is assumed to be known. The second method expands the electromagnetic field in normal modes (planewaves in a box with periodic boundary-conditions) and solves the equation for wave amplitudes coupled to the particle motion. The third method is a hybrid molecular dynamics/Monte Carlo (MD/MC) method which calculates radiation emitted or absorbed by electron-ion pairs during close collisions. The fourth method is a generalization of the third method to include small clusters of particles emitting radiation during close encounters: one electron simultaneously hitting two ions, two electrons simultaneously hitting one ion, etc. This approach is inspired by the virial expansion method of equilibrium statistical mechanics. Using a combination of these methods we believe it is possible to do atomic-scale particle

  17. Non-Linearity of dose-effect relationship on the example of cytogenetic effects in plant cells at low level exposure to ionising radiation

    Energy Technology Data Exchange (ETDEWEB)

    Oudalova, Alla; Geras' kin, Stanislav; Dikarev, Vladimir; Dikareva, Nina; Chernonog, Elena [Russian Institute of Agricultural Radiology and Agroecology, RIARAE, 249032 Obninsk (Russian Federation); Copplestone, David [Environment Agency, Millbank Tower, 25th. Floor, 21/24 Millbank, London, SW1P 4XL (United Kingdom); Evseeva, Tatyana [Institute of Biology, Kommunisticheskaya st., 28 Syktyvkar 167610, Komi Republic (Russian Federation)

    2006-07-01

    Over several decades, modelling the effects of ionizing radiation on biological system has relied on the target principle [Timofeeff-Ressovsky et al., 1935], which assumes that cell damage or modification to genes appear as a direct consequence of the exposure of biological macromolecules to charged particles. Furthermore, it is assumed that there is no threshold for the induction of biological damage and that the effects observed are proportional to the energy absorbed. Following this principle, the average number of hits per target should increase linearly with dose, and the yield of mutations per unit of dose is assumed to be the same at both low and high doses (linearity of response). This principle has served as the scientific background for the linear no-threshold (LNT) concept that forms the basis for the radiological protection for the public and the environment [ICRP, 1990]. It follows from the LNT that there is an additional risk for human health from exposure to any radiation level, even below natural background. Since the mid 50's, however, the scientific basis for the LNT concept has been challenged as experimental data have shown that, at low doses, there was a non linear relationship in the dose response. Luchnik and Timofeeff-Ressovsky were the first who showed a non-linear response to a low dose exposure [Luchnik, 1957; Timofeeff-Ressovsky and Luchnik, 1960]. Since then, many data have been accumulated which contradict the LNT model at low doses and dose rates. However, the hit-effect paradigm has become such a strong and indissoluble fact that it has persisted even under the growing pressure of scientific evidence for phenomena at low dose exposure that can not be successfully accounted for by the LNT concept. In recent years, additional information on non-targeted effects of radiation has been accumulated following the first reports of an adaptive response in human lymphocytes [Olivieri et al., 1984] as well as bystander mutagenic effect of

  18. Ultraviolet radiation in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Taalas, P.; Koskela, T.; Damski, J.; Supperi, A. [Finnish Meteorological Inst., Helsinki (Finland). Section of Ozone and UV Research; Kyroe, E. [Finnish Meteorological Inst., Sodankylae (Finland). Sodankylae Observatory

    1996-12-31

    Solar ultraviolet radiation is damaging for living organisms due to its high energy pro each photon. The UV radiation is often separated into three regions according to the wavelength: UVC (200-280 nm), UVB (280-320 nm) and UVA (320-400 nm). The most hazardous part, UVC is absorbed completely in the upper atmosphere by molecular oxygen. UVB radiation is absorbed by atmospheric ozone partly, and it is reaching Earth`s surface, as UVA radiation. Besides atmospheric ozone, very important factors in determining the intensity of UVB radiation globally are the solar zenith angle and cloudiness. It may be calculated from global ozone changes that the clear-sky UVB doses may have enhanced by 10-15 % during spring and 5-10 % during summer at the latitudes of Finland, following the decrease of total ozone between 1979-90. The Finnish ozone and UV monitoring activities have become a part of international activities, especially the EU Environment and Climate Programme`s research projects. The main national level effort has been the Finnish Academy`s climatic change programme, SILMU 1990-95. This presentation summarises the scientific results reached during the SILMU project

  19. Radiation Shielding Materials

    Science.gov (United States)

    Adams, James H., Jr.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    NASA has relied on the materials to provide radiation shielding for astronauts since the first manned flights. Until very recently existing materials in the structure of manned spacecraft as well as the equipment and consumables onboard have been taken advantage of for radiation shielding. With the advent of the International Space Station and the prospect of extended missions to the Moon or Mars, it has been found that the materials, which were included in the spacecraft for other reasons, do not provide adequate shielding. For the first time materials are being added to manned missions solely to improve the radiation shielding. It is now recognized that dual use materials must be identified/developed. These materials must serve a purpose as part of the spacecraft or its cargo and at the same time be good shielding. This paper will review methods for evaluating the radiation shielding effectiveness of materials and describe the character of materials that have high radiation shielding effectiveness. Some candidate materials will also be discussed.

  20. Surprising radiation detectors

    CERN Document Server

    Fleischer, Robert

    2003-01-01

    Radiation doses received by the human body can be measured indirectly and retrospectively by counting the tracks left by particles in ordinary objects like pair of spectacles, glassware, compact disks...This method has been successfully applied to determine neutron radiation doses received 50 years ago on the Hiroshima site. Neutrons themselves do not leave tracks in bulk matter but glass contains atoms of uranium that may fission when hurt by a neutron, the recoil of the fission fragments generates a track that is detectable. The most difficult is to find adequate glass items and to evaluate the radiation shield they benefited at their initial place. The same method has been used to determine the radiation dose due to the pile-up of radon in houses. In that case the tracks left by alpha particles due to the radioactive decay of polonium-210 have been counted on the superficial layer of the window panes. Other materials like polycarbonate plastics have been used to determine the radiation dose due to heavy io...

  1. SKIN RADIATION IN PANORAMIC

    Directory of Open Access Journals (Sweden)

    Herry Irawan

    2015-06-01

    Full Text Available Dental panoramic radiograph in Indonesia has been widely used. Modern diagnostic imaging equipment with minimum radiation is still very limited. One of the conditions in nuclear safety law, UU 10/1997, is an optimization of all radiation sources with DRL through skin dose measurements. In Indonesia, the national DRL has not been established yet, and there were no reports on the study of panoramic skin dose in Indonesia. The aim of this preliminary study was to obtain a panoramic skin dose radiation as reference to establish DRL in Indonesia. Panoramic radiographs of sixteen female and fifteen male patients, aged 4 – 48 years, were taken using the standard conventional method, with TLD chips attached in location groups. The chips were then read with the detector and integrator of BATAN, in high and low temperature condition at the same time. It was revealed that behind the right and left ear were the regions with the highest radiation dose received, followed by the back of the neck, left jaw, right jaw, and chin. The result of this study has shown the importance of DRL in Indonesia since the use of modern diagnostic imaging equipement that limits radiation dose to the minimum level is still very limited.

  2. Radiation exposure analysis of female nuclear medicine radiation workers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Young [Dept. of Biomedical Engineering Graduate School, Chungbuk National University, Cheongju (Korea, Republic of); Park, Hoon Hee [Dept. of Radiological Technologist, Shingu College, Sungnam (Korea, Republic of)

    2016-06-15

    In this study, radiation workers who work in nuclear medicine department were analyzed to find the cause of differences of radiation exposure from General Characteristic, Knowledge, Recognition and Conduct, especially females working on nuclear medicine radiation, in order to pave the way for positive defense against radiation exposure. The subjects were 106 radiation workers who were divided into two groups of sixty-four males and forty-two females answered questions about their General Characteristic, Knowledge, Recognition, Conduct, and radiation exposure dose which was measured by TLD (Thermo Luminescence Dosimeter). The results of the analysis revealed that as the higher score of knowledge and conduct was shown, the radiation exposure decreased in female groups, and as the higher score of conduct was shown, the radiation exposure decreased in male groups. In the correlation analysis of female groups, the non-experienced in pregnancy showed decreasing amount of radiation exposure as the score of knowledge and conduct was higher and the experienced in pregnancy showed decreasing amount of radiation exposure as the score of recognition and conduct was higher. In the regression analysis on related factors of radiation exposure dose of nuclear medicine radiation workers, the gender caused the meaningful result and the amount of radiation exposure of female groups compared to male groups. In the regression analysis on related factors of radiation exposure dose of female groups, the factor of conduct showed a meaningful result and the amount of radiation exposure of the experienced in pregnancy was lower compared to the non-experienced. The conclusion of this study revealed that radiation exposure of female groups was lower than that of male groups. Therefore, male groups need to more actively defend themselves against radiation exposure. Among the female groups, the experienced in pregnancy who have an active defense tendency showed a lower radiation exposure. Thus

  3. Radiation techniques for acromegaly

    Directory of Open Access Journals (Sweden)

    Minniti Giuseppe

    2011-12-01

    Full Text Available Abstract Radiotherapy (RT remains an effective treatment in patients with acromegaly refractory to medical and/or surgical interventions, with durable tumor control and biochemical remission; however, there are still concerns about delayed biochemical effect and potential late toxicity of radiation treatment, especially high rates of hypopituitarism. Stereotactic radiotherapy has been developed as a more accurate technique of irradiation with more precise tumour localization and consequently a reduction in the volume of normal tissue, particularly the brain, irradiated to high radiation doses. Radiation can be delivered in a single fraction by stereotactic radiosurgery (SRS or as fractionated stereotactic radiotherapy (FSRT in which smaller doses are delivered over 5-6 weeks in 25-30 treatments. A review of the recent literature suggests that pituitary irradiation is an effective treatment for acromegaly. Stereotactic techniques for GH-secreting pituitary tumors are discussed with the aim to define the efficacy and potential adverse effects of each of these techniques.

  4. Physics: unknown radiation

    CERN Document Server

    Grenier, E; Liksonov, V I; Tsinoiev, V G

    2002-01-01

    This article reports experiments concerning the study of the electrical explosion of a titanium foil in water. During the electrical discharge a strong luminescence appears, the analysis of spectra shows the presence of new chemical elements and this presence is confirmed by the mass-spectrometry measurements performed on the precipitates found after the discharge. This experiment has been repeated about 200 times and the results are consistent an show an average titanium transmutation rate of 4%. Neither gamma nor neutron radiation have been detected but an unknown radiation, sensitive to magnetic fields, has been detected through tracks left on RF-ZMP fluo-graphical films covered with a 10 mu m-thick emulsion layer. The assumption of a radiation made up of magnetic monopoles is supported by the author. (A.C.)

  5. Radiation induced pesticidal microbes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Y. K.; Kim, J. S.; Kim, J. K.; Lee, S. J.; Lim, D. S

    2001-01-01

    To isolate pesticidal microbes against plant pathogenic fungi, 4 strains of bacteria(K1. K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 12 kinds of fungi. Specific proteins and the specific transcribed genes were found from the YS1 and its radiation-induced mutants. And knock-out mutants of antifungal activity were derived by transposon mutagenesis. From these knock-out mutants, the antifungal activity related genes and its modification by gamma-ray radiation are going to be studied. These results suggested that radiation could be an useful tool for the induction of functional mutants.

  6. Space radiation protection issues.

    Science.gov (United States)

    Kronenberg, Amy; Cucinotta, Francis A

    2012-11-01

    The complex charged particle environments in space pose considerable challenges with regard to potential health consequences that can impact mission design and crew selection. The lack of knowledge of the biological effects of different ions in isolation and in combination is a particular concern because the risk uncertainties are very high for both cancer and non-cancer late effects. Reducing the uncertainties is of high priority. Two principal components of space radiation each raise different concerns. Solar particle events (SPE) occur sporadically and are comprised primarily of low- to moderate-energy protons. Galactic cosmic radiation (GCR) is isotropic and relatively invariant in dose rate. GCR is also dominated by protons, but the energy range is wider than in SPE. In addition, the contribution of other light and heavy ions to the health risks from GCR must be addressed. This paper will introduce the principal issues under consideration for space radiation protection.

  7. Radiation induced oral mucositis

    Directory of Open Access Journals (Sweden)

    P S Satheesh Kumar

    2009-01-01

    Full Text Available Patients receiving radiotherapy or chemotherapy will receive some degree of oral mucositis The incidence of oral mucositis was especially high in patients: (i With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii who also received concomitant chemotherapy; (iii who received a total dose over 5,000 cGy; and (iv who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene

  8. Transition Radiation Detectors

    CERN Document Server

    Andronic, A

    2012-01-01

    We review the basic features of transition radiation and how they are used for the design of modern Transition Radiation Detectors (TRD). The discussion will include the various realizations of radiators as well as a discussion of the detection media and aspects of detector construction. With regard to particle identification we assess the different methods for efficient discrimination of different particles and outline the methods for the quantification of this property. Since a number of comprehensive reviews already exist, we predominantly focus on the detectors currently operated at the LHC. To a lesser extent we also cover some other TRDs, which are planned or are currently being operated in balloon or space-borne astro-particle physics experiments.

  9. Radiative accidental matter

    CERN Document Server

    Sierra, D Aristizabal; Wegman, D

    2016-01-01

    Accidental matter models are scenarios where the beyond-the-standard model physics preserves all the standard model accidental and approximate symmetries up to a cutoff scale related with lepton number violation. We study such scenarios assuming that the new physics plays an active role in neutrino mass generation, and show that this unavoidably leads to radiatively induced neutrino masses. We systematically classify all possible models and determine their viability by studying electroweak precision data, big bang nucleosynthesis and electroweak perturbativity, finding that the latter places the most stringent constraints on the mass spectra. These results allow the identification of minimal radiative accidental matter models for which perturbativity is lost at high scales. We calculate radiative charged-lepton flavor violating processes in these setups, and show that $\\mu\\to e \\gamma$ has a rate well within MEG sensitivity provided the lepton-number violating scale is at or below $10^6\\,$ GeV, a value (natur...

  10. Digital Radiation image

    Directory of Open Access Journals (Sweden)

    Abou-Bakr Ramadan

    2012-03-01

    Full Text Available This work introduces a new way for data visualization. Its name is Digital Application name' Image. Normal digital image is created by digital camera or digital scanner but digital application name image is created by measurements of monitoring data. This work uses the data which is measured by radiation monitoring station and classifies it using fuzzy logic rules to create digital radiation image. The main unique advantage of digital radiation image is that it expresses thousands of measurements in a very clear form through only one picture while the maximum number of measurements does not exceed 100 with other conventional visualization methods. This feature gives a facility to view one year of all recorded measurements in only one photo. This picture helps the user to observe the behavior of thousands of measurements in few minutes instead of spending few hours for reviewing hundreds of charts for the same measurements.

  11. Involved Node Radiation Therapy

    DEFF Research Database (Denmark)

    Maraldo, Maja V; Aznar, Marianne C; Vogelius, Ivan R

    2012-01-01

    PURPOSE: The involved node radiation therapy (INRT) strategy was introduced for patients with Hodgkin lymphoma (HL) to reduce the risk of late effects. With INRT, only the originally involved lymph nodes are irradiated. We present treatment outcome in a retrospective analysis using this strategy...... to 36 Gy). Patients attended regular follow-up visits until 5 years after therapy. RESULTS: The 4-year freedom from disease progression was 96.4% (95% confidence interval: 92.4%-100.4%), median follow-up of 50 months (range: 4-71 months). Three relapses occurred: 2 within the previous radiation field......, and 1 in a previously uninvolved region. The 4-year overall survival was 94% (95% confidence interval: 88.8%-99.1%), median follow-up of 58 months (range: 4-91 months). Early radiation therapy toxicity was limited to grade 1 (23.4%) and grade 2 (13.8%). During follow-up, 8 patients died, none from HL, 7...

  12. Case of radiation myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Hatano, Noriyoshi; Iwamoto, Toshihiko; Hagiwara, Akiyoshi; Sato, Yoshihito; Shimizu, Nobuya; Takagi, Yasushi

    1988-03-01

    A 72-year-old woman presented with right hemiparesthesia and left hemiparalysis. At the age of 63, the patient was treated with pre- and post-operative radiation with a total dose of 100 Gy for maxillary squamous cell carcinoma. Five years later, a dose of 50 Gy was delivered again to the head and neck because of the suspicion of recurrence. Magnetic resonance imaging showed flat and thinned cervical spine on the transverse section and markedly atrophied cervical spine at the C1 to C3 levels on the sagittal section. She was diangosed as having chronic progressive radiation myelopathy in view of a history of large doses of radiation to the head and neck. (Namekawa, K.).

  13. Radiation Protection Research: Radiobiology

    Energy Technology Data Exchange (ETDEWEB)

    Desaintes, C

    2000-07-01

    The main objectives of research in the field of radiobiology and epidemiology performed at the Belgian Nuclear Research Centre SCK-CEN are (1) to study cancer mortality in nuclear workers in Belgium; to document the feasibility of retrospective cohort studies in Belgium; (2) to participate in the IARC study; (3) to elucidate the molecular basis of the effects of ionising radiation in the mammalian embryo during the early phases of its development; (4) to assess the genetic risk of maternal exposure to ionizing radiation; (5) to elucidate the cellular mechanisms leading to brain damage after prenatal irradiation; (6) to advise authorities and to provide the general population with adequate information concerning the health risk arising from radiation exposure. Progress and major achievements in these topical areas in 1999 are reported.

  14. Audible radiation monitor

    Energy Technology Data Exchange (ETDEWEB)

    Odell, D.M.C.

    1992-12-31

    This invention consists of a method and apparatus for monitoring ionizing radiation comprising radiation detectors in electrical connection with an isotopic analyzer and a device for producing chords to which each isotope is mapped so that the device produces a unique chord for each isotope. Preferably the chords are pleasing to the ear, except for chords representing unexpected isotopes, and are louder or softer depending on the level of radioactivity produced by each isotope, and musical instrument voices may be simulated in producing the chords as an aid to distinguishing similar-sounding chords. Because of the representation by chords, information regarding the level and composition of the radiation in an area can be conveyed to workers in that area more effectively and yet without distracting them.

  15. Properties of undulator radiation

    Energy Technology Data Exchange (ETDEWEB)

    Veal, B.W.

    1985-11-01

    Properties of the radiation emitted by a plane sinusoidal undulator are calculated in the far field approximation. Software has been developed to calculate the spectral distribution and polarization of the radiated intensity I(E) at a point on (or integrated over) a cross sectional observation plane of the photon beam. Spatial distribution of monochromatic radiation and power density contours are also calculated. Spectral broadening caused by an electron beam of finite spatial distribution is considered. Dispersive properties of the photon beam, including the dependence on deflection parameter, are analyzed. It is shown that reasonably constant intensity distribution I(E) can be obtained by properly shaping the beam acceptance aperture. 5 refs., 11 figs.

  16. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  17. Radiation in Particle Simulations

    Energy Technology Data Exchange (ETDEWEB)

    More, R M; Graziani, F R; Glosli, J; Surh, M

    2009-06-15

    Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of Megabars to thousands of Gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present four methods that attempt a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The first method applies the Lienard-Weichert solution of Maxwell's equations for a classical particle whose motion is assumed to be known (section 3). The second method expands the electromagnetic field in normal modes (plane-waves in a box with periodic boundary-conditions) and solves the equation for wave amplitudes coupled to the particle motion (section 4). The third method is a hybrid MD/MC (molecular dynamics/Monte Carlo) method which calculates radiation emitted or absorbed by electron-ion pairs during close collisions (section 5). The fourth method is a generalization of the third method to include small clusters of particles emitting radiation during close encounters: one electron simultaneously hitting two ions, two electrons simultaneously hitting one ion, etc.(section 6). This approach is inspired by the Virial expansion method of equilibrium statistical mechanics.

  18. Radiative plateau inflation

    CERN Document Server

    Ballesteros, Guillermo

    2016-01-01

    We describe how monomial chaotic inflation becomes compatible with the latest CMB data thanks to radiative corrections producing a plateau. The interactions of the inflation with other fields, required for reheating, can flatten the potential and moderate the production of primordial gravitational waves, keeping these below the current upper bound. We show that the appearance of a plateau requires that the inflaton couples to fermions and to another scalar or a gauge group. We give concrete examples of minimal particle physics models leading to plateaus for quadratic and quartic chaotic inflation. We also provide a three-parameter model-independent description of radiatively corrected inflation that is amenable to CMB analyses.

  19. ATHENA radiation model

    Energy Technology Data Exchange (ETDEWEB)

    Shumway, R.W.

    1987-10-01

    The ATHENA computer program has many features that make it desirable to use as a space reactor evaluation tool. One of the missing features was a surface-to-surface thermal radiation model. A model was developed that allows any of the regular ATHENA heat slabs to radiate to any other heat slab. The view factors and surface emissivities must be specified by the user. To verify that the model was properly accounting for radiant energy transfer, two different types of test calculations were performed. Both calculations have excellent results. The updates have been used on both the INEL CDC-176 and the Livermore Cray. 7 refs., 2 figs., 6 tabs.

  20. Radiation Detectors and Art

    Science.gov (United States)

    Denker, Andrea

    The use of radiation detectors in the analysis of art objects represents a very special application in a true interdisciplinary field. Radiation detectors employed in this field detect, e.g., x-rays, γ-rays, β particles, and protons. Analyzed materials range from stones, metals, over porcelain to paintings. The available nondestructive and noninvasive analytical methods cover a broad range of techniques. Hence, for the sake of brevity, this chapter will concentrate on few techniques: Proton Induced X-ray Emission (PIXE) and Proton Induced γ-ray Emission (PIGE).

  1. Radiation Monitoring Equipment Dosimeter Experiment

    Science.gov (United States)

    Hardy, Kenneth A.; Golightly, Michael J.; Quam, William

    1992-01-01

    Spacecraft crews risk exposure to relatively high levels of ionizing radiation. This radiation may come from charged particles trapped in the Earth's magnetic fields, charged particles released by solar flare activity, galactic cosmic radiation, energetic photons and neutrons generated by interaction of these primary radiations with spacecraft and crew, and man-made sources (e.g., nuclear power generators). As missions are directed to higher radiation level orbits, viz., higher altitudes and inclinations, longer durations, and increased flight frequency, radiation exposure could well become a major factor for crew stay time and career lengths. To more accurately define the radiological exposure and risk to the crew, real-time radiation monitoring instrumentation, which is capable of identifying and measuring the various radiation components, must be flown. This presentation describes a radiation dosimeter instrument which was successfully flown on the Space Shuttle, the RME-3.

  2. Radiative Magnetic Reconnection in Astrophysics

    CERN Document Server

    Uzdensky, Dmitri A

    2015-01-01

    I review a new rapidly growing area of high-energy plasma astrophysics --- radiative magnetic reconnection, i.e., a reconnection regime where radiation reaction influences reconnection dynamics, energetics, and nonthermal particle acceleration. This influence be may be manifested via a number of astrophysically important radiative effects, such as radiation-reaction limits on particle acceleration, radiative cooling, radiative resistivity, braking of reconnection outflows by radiation drag, radiation pressure, viscosity, and even pair creation at highest energy densities. Self-consistent inclusion of these effects in magnetic reconnection theory and modeling calls for serious modifications to our overall theoretical approach to the problem. In addition, prompt reconnection-powered radiation often represents our only observational diagnostic tool for studying remote astrophysical systems; this underscores the importance of developing predictive modeling capabilities to connect the underlying physical condition...

  3. Effects of radiation; Effets des radiations

    Energy Technology Data Exchange (ETDEWEB)

    Masse, R. [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France)

    2006-07-01

    The medical consequences of a whole-body irradiation come from the destruction of cells and inflammatory reactions it provokes. The most sensitive organs are the tissues that actively split. The embryo is particularly sensitive, from 200 mSv for the effects on the brain development. The reproduction functions are reached for man from 2000 mSv, the ovary sensitivity is less, the oocytes do not split after the fetus life. For adult the bone marrow outrage leads to the disappearing of blood cells (4000 mSv). The doses from 6000 to 10000 mSv lead the failure of the digestive system and lung. for the upper doses every tissue is reached, particularly by the effects on cells of blood vessels. Important brain dysfunctions appear beyond 10000 mSv. As regards the delayed effects of overexposures the epidemiology brings to light sanitary consequences of the exposure of the population to the ionizing radiations and requires that all the possible factors associated for that purpose are considered. About hereditary effects, it appears that moderate acute radiation exposures of even a relatively large human population must have little impact, in spite of the rate of spontaneous congenital deformations is of the order of 6 %. For the induction of cancers, it is not observed excess for doses lower than 200 mSv for adults and 100 mSv for children (the populations studied are survival people of hiroshima and Nagasaki, patients treated by irradiation, uranium miners, children exposed to radioactive iodine after Chernobylsk accident). To simplify an expression of the risk has been fixed to 5% of induced cancer by Sv for population and 4% by Sv for workers, the different being explained by the demography and the sensitivity of the youngest age groups. As regards the low doses of radiations, a bundle of convergent epidemiological observations notices the absence of effects of the low doses rates. Biological mechanisms, notably of repair are approached, then certain accidents (Goiania

  4. Ionizing radiation injuries and illnesses.

    Science.gov (United States)

    Christensen, Doran M; Iddins, Carol J; Sugarman, Stephen L

    2014-02-01

    Although the spectrum of information related to diagnosis and management of radiation injuries and illnesses is vast and as radiation contamination incidents are rare, most emergency practitioners have had little to no practical experience with such cases. Exposures to ionizing radiation and internal contamination with radioactive materials can cause significant tissue damage and conditions. Emergency practitioners unaware of ionizing radiation as the cause of a condition may miss the diagnosis of radiation-induced injury or illness. This article reviews the pertinent terms, physics, radiobiology, and medical management of radiation injuries and illnesses that may confront the emergency practitioner. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Radiation Safety in Pediatric Orthopaedics.

    Science.gov (United States)

    Caird, Michelle S

    2015-01-01

    Patients, surgeons, and staff are exposed to ionizing radiation in pediatric orthopaedic surgery from diagnostic studies and imaging associated with procedures. Estimating radiation dose to pediatric patients is based on complex algorithms and dose to surgeons and staff is based on dosimeter monitoring. Surgeons can decrease radiation exposure to patients with careful and thoughtful ordering of diagnostic studies and by minimizing exposure intraoperatively. Surgeon and staff radiation exposure can be minimized with educational programs, proper shielding and positioning intraoperatively, and prudent use of intraoperative imaging. Overall, better awareness among pediatric orthopaedic surgeons of our role in radiation exposure can lead to improvements in radiation safety.

  6. Paradoxes of Thermal Radiation

    Science.gov (United States)

    Besson, U.

    2009-01-01

    This paper presents an analysis of the thermal behaviour of objects exposed to a solar-type flux of thermal radiation. It aims to clarify certain apparent inconsistencies between theory and observation, and to give a detailed exposition of some critical points that physics textbooks usually treat in an insufficient or incorrect way. In particular,…

  7. Evidence for extra radiation?

    DEFF Research Database (Denmark)

    Hamann, J.

    2012-01-01

    during the marginalisation process, and we demonstrate that the effect is related to the fact that cosmic microwave background (CMB) data constrain N_eff only indirectly via the redshift of matter-radiation equality. Once present CMB data are combined with external information about, e.g., the Hubble...

  8. Nanofocusing of electromagnetic radiation

    DEFF Research Database (Denmark)

    Gramotnev, D. K.; Bozhevolnyi, Sergey I.

    2014-01-01

    Nanofocusing of electromagnetic radiation, that is, reducing the cross sections of propagating optical modes far beyond the diffraction limit in dielectric media, can be achieved in tapered metal-dielectric waveguides that support surface plasmon-polariton modes. Although the main principles...

  9. Radiative Corrections and Z'

    CERN Document Server

    Erler, Jens

    2009-01-01

    Radiative corrections to parity violating deep inelastic electron scattering are reviewed including a discussion of the renormalization group evolution of the weak mixing angle. Recently obtained results on hypothetical Z' bosons - for which parity violating observables play an important role - are also presented.

  10. Thermostatic Radiator Valve Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, J.; Ansanelli, E.

    2015-01-01

    A large stock of multifamily buildings in the Northeast and Midwest are heated by steam distribution systems. Losses from these systems are typically high and a significant number of apartments are overheated much of the time. Thermostatically controlled radiator valves (TRVs) are one potential strategy to combat this problem, but have not been widely accepted by the residential retrofit market.

  11. Microwave Radiation Hazards

    Directory of Open Access Journals (Sweden)

    G. Subrahmanian

    1973-07-01

    Full Text Available Excessive exposure to microwave radiation could lead to biological damage. The criteria for maximum permissible exposure limits derived from experiments by several countries are discussed. Recommendations made for safety of operating personnel based on a recent protection survey are also presented.

  12. Radiation damping on cryoprobes.

    Science.gov (United States)

    Shishmarev, Dmitry; Otting, Gottfried

    2011-12-01

    Radiation damping on 600 and 800 MHz cryoprobes was investigated. The phase angle β between a vector 90° phase shifted to the precessing magnetization and the rf field induced in the coil was found to depend markedly on whether an FID was being acquired or not. The magnitude of the radiation damping field was sufficiently strong to restore 95% of the equilibrium water magnetization of a 90% H2O sample in a 5 mm sample tube within about 5 ms following a 165° pulse. This can be exploited in water flip-back versions of NOESY and TOCSY experiments of proteins, but care must be taken to limit the effect of the radiation damping field from the water on the Ha protons. Long water-selective pulses can be applied only following corrections. We developed a program for correcting pulse shapes if β is non-zero. The WATERGATE scheme is shown to be insensitive to imperfections introduced by radiation damping.

  13. Detection of gravitational radiation

    Energy Technology Data Exchange (ETDEWEB)

    Holten, J.W. van [ed.

    1994-12-31

    In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI).

  14. Modeling Radiation Fog

    Science.gov (United States)

    K R, Sreenivas; Mohammad, Rafiuddin

    2016-11-01

    Predicting the fog-onset, its growth and dissipation helps in managing airports and other modes of transport. After sunset, occurrence of fog requires moist air, low wind and clear-sky conditions. Under these circumstances radiative heat transfer plays a vital role in the NBL. Locally, initiation of fog happens when the air temperature falls below the dew-point. Thus, to predict the onset of fog at a given location, one has to compute evolution of vertical temperature profile. Earlier,our group has shown that the presence of aerosols and vertical variation in their number density determines the radiative-cooling and hence development of vertical temperature profile. Aerosols, through radiation in the window-band, provides an efficient path for air layers to lose heat to the cold, upper atmosphere. This process creates cooler air layer between warmer ground and upper air layers and resulting temperature profile facilitate the initiation of fog. Our results clearly indicates that accounting for the presence of aerosols and their radiative-transfer is important in modeling micro-meteorological process of fog formation and its evolution. DST, Govt. INDIA.

  15. VDT Emissions Radiate Debate.

    Science.gov (United States)

    Morgan, Bill

    1990-01-01

    Discusses the possible health effects of electromagnetic fields of radiation that are emitted from video display terminals (VDTs). Responses from vendors in the computer industry are related, steps to reduce possible risks are suggested, and additional sources of information on VDTs are listed. (LRW)

  16. Radiation monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    Aghina, Mauricio A.C.; Farias, Marcos S. de; Lacerda, Fabio de; Heimlich, Adino [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    Design of a portable low-power multichannel analyzer with wireless connectivity for remote radiation monitoring, powered from a solar panel with a internal battery to be operated in field. The multichannel analyzer is based on a single microcontroller which performs the digital functions and an analog signal processing board for implementing a Gaussian shaper preamplifier, a Gaussian stretcher, sample and hold, pile-up rejector and a 10 bit ADC. Now this design is to be used with a NaI(Ti) scintillator detector. This multichannel analyzer is designed to be a part of radiation monitoring network. All of them are connected, by radio in a radius of 10 kilometers, to a supervisor computer that collects data from the network of multichannel analyzers and numerically display the latest radiation measurements or graphically display measurements over time for all multichannel analyzers. Like: dose rate, spectra and operational status. Software also supports remotely configuring operating parameters (such as radiation alarm level) for each monitor independently. (author)

  17. Radiation Source Replacement Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  18. Thermodynamics of Radiation Modes

    Science.gov (United States)

    Pina, Eduardo; de la Selva, Sara Maria Teresa

    2010-01-01

    We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the…

  19. Paradoxes of Thermal Radiation

    Science.gov (United States)

    Besson, U.

    2009-01-01

    This paper presents an analysis of the thermal behaviour of objects exposed to a solar-type flux of thermal radiation. It aims to clarify certain apparent inconsistencies between theory and observation, and to give a detailed exposition of some critical points that physics textbooks usually treat in an insufficient or incorrect way. In particular,…

  20. Management of ionizing radiation injuries and illnesses, part 1: physics, radiation protection, and radiation instrumentation.

    Science.gov (United States)

    Christensen, Doran M; Jenkins, Mark S; Sugarman, Stephen L; Glassman, Erik S

    2014-03-01

    Ionizing radiation injuries and illnesses are exceedingly rare; therefore, most physicians have never managed such conditions. When confronted with a possible radiation injury or illness, most physicians must seek specialty consultation. Protection of responders, health care workers, and patients is an absolute priority for the delivery of medical care. Management of ionizing radiation injuries and illnesses, as well as radiation protection, requires a basic understanding of physics. Also, to provide a greater measure of safety when working with radioactive materials, instrumentation for detection and identification of radiation is needed. Because any health care professional could face a radiation emergency, it is imperative that all institutions have emergency response plans in place before an incident occurs. The present article is an introduction to basic physics, ionizing radiation, radiation protection, and radiation instrumentation, and it provides a basis for management of the consequences of a radiologic or nuclear incident.

  1. Integrative Radiation Biology

    Energy Technology Data Exchange (ETDEWEB)

    Barcellos-Hoff, Mary Helen [New York University School of Medicine, NY (United States)

    2015-02-27

    We plan to study tissue-level mechanisms important to human breast radiation carcinogenesis. We propose that the cell biology of irradiated tissues reveals a coordinated multicellular damage response program in which individual cell contributions are primarily directed towards suppression of carcinogenesis and reestablishment of homeostasis. We identified transforming growth factor β1 (TGFβ) as a pivotal signal. Notably, we have discovered that TGFβ suppresses genomic instability by controlling the intrinsic DNA damage response and centrosome integrity. However, TGFβ also mediates disruption of microenvironment interactions, which drive epithelial to mesenchymal transition in irradiated human mammary epithelial cells. This apparent paradox of positive and negative controls by TGFβ is the topic of the present proposal. First, we postulate that these phenotypes manifest differentially following fractionated or chronic exposures; second, that the interactions of multiple cell types in tissues modify the responses evident in this single cell type culture models. The goals are to: 1) study the effect of low dose rate and fractionated radiation exposure in combination with TGFβ on the irradiated phenotype and genomic instability of non-malignant human epithelial cells; and 2) determine whether stromal-epithelial interactions suppress the irradiated phenotype in cell culture and the humanized mammary mouse model. These data will be used to 3) develop a systems biology model that integrates radiation effects across multiple levels of tissue organization and time. Modeling multicellular radiation responses coordinated via extracellular signaling could have a significant impact on the extrapolation of human health risks from high dose to low dose/rate radiation exposure.

  2. Delayed radiation neuropathy

    Energy Technology Data Exchange (ETDEWEB)

    Nagashima, T.; Miyamoto, K.; Beppu, H.; Hirose, K.; Yamada, K. (Tokyo Metropolitan Neurological Hospital (Japan))

    1981-07-01

    A case of cervical plexus neuropathy was reported in association with chronic radio-dermatitis, myxedema with thyroid adenoma and epiglottic tumor. A 38-year-old man has noticed muscle weakness and wasting of the right shoulder girdle since age 33. A detailed history taking revealed a previous irradiation to the neck because of the cervical lymphadenopathy at age 10 (X-ray 3,000 rads), keroid skin change at age 19, obesity and edema since 26, and hoarseness at 34. Laryngoscopic examination revealed a tumor on the right vocal cord, diagnosed as benign papilloma by histological study. In addition, there were chronic radio-dermatitis around the neck, primary hypothyroidism with a benign functioning adenoma on the right lobe of the thyroid, the right phrenic nerve palsy and the right recurrent nerve palsy. All these lesions were considered to be the late sequellae of radiation to the neck in childhood. Other neurological signs were weakness and amyotrophy of the right shoulder girdle with patchy sensory loss, and areflexia of the right arm. Gross power was fairly well preserved in the right hand. EMG showed neurogenic changes in the tested muscles, suggesting a peripheral nerve lesion. Nerve conduction velocities were normal. No abnormal findings were revealed by myelography and spinal CT. The neurological findings of the patient were compatible with the diagnosis of middle cervical plexus palsy apparently due to late radiation effect. In the literature eight cases of post-radiation neuropathy with a long latency have been reported. The present case with the longest latency after the radiation should be included in the series of the reported cases of ''delayed radiation neuropathy.'' (author).

  3. Spacecraft Electrostatic Radiation Shielding

    Science.gov (United States)

    2008-01-01

    This project analyzed the feasibility of placing an electrostatic field around a spacecraft to provide a shield against radiation. The concept was originally proposed in the 1960s and tested on a spacecraft by the Soviet Union in the 1970s. Such tests and analyses showed that this concept is not only feasible but operational. The problem though is that most of this work was aimed at protection from 10- to 100-MeV radiation. We now appreciate that the real problem is 1- to 2-GeV radiation. So, the question is one of scaling, in both energy and size. Can electrostatic shielding be made to work at these high energy levels and can it protect an entire vehicle? After significant analysis and consideration, an electrostatic shield configuration was proposed. The selected architecture was a torus, charged to a high negative voltage, surrounding the vehicle, and a set of positively charged spheres. Van de Graaff generators were proposed as the mechanism to move charge from the vehicle to the torus to generate the fields necessary to protect the spacecraft. This design minimized complexity, residual charge, and structural forces and resolved several concerns raised during the internal critical review. But, it still is not clear if such a system is costeffective or feasible, even though several studies have indicated usefulness for radiation protection at energies lower than that of the galactic cosmic rays. Constructing such a system will require power supplies that can generate voltages 10 times that of the state of the art. Of more concern is the difficulty of maintaining the proper net charge on the entire structure and ensuring that its interaction with solar wind will not cause rapid discharge. Yet, if these concerns can be resolved, such a scheme may provide significant radiation shielding to future vehicles, without the excessive weight or complexity of other active shielding techniques.

  4. The importance of microdosimetry for radiation biology and radiation protection

    NARCIS (Netherlands)

    Barendsen, G.W.

    1967-01-01

    In this contribution several features will be discussed of relations between biological effects produced by ionizing radiations and the spatial distributions of energy deposition of these radiations. Effects produced by high-LET radiations are generally found to be less dependent on dose-rate, dose-

  5. The importance of microdosimetry for radiation biology and radiation protection

    NARCIS (Netherlands)

    Barendsen, G.W.

    1967-01-01

    In this contribution several features will be discussed of relations between biological effects produced by ionizing radiations and the spatial distributions of energy deposition of these radiations. Effects produced by high-LET radiations are generally found to be less dependent on dose-rate,

  6. Radiation physics for medical physicists

    CERN Document Server

    Podgorsak, Ervin B

    2016-01-01

    This textbook summarizes the basic knowledge of atomic, nuclear, and radiation physics that professionals working in medical physics and biomedical engineering need for efficient and safe use of ionizing radiation in medicine. Concentrating on the underlying principles of radiation physics, the textbook covers the prerequisite knowledge for medical physics courses on the graduate and post-graduate levels in radiotherapy physics, radiation dosimetry, imaging physics, and health physics, thus providing the link between elementary undergraduate physics and the intricacies of four medical physics specialties: diagnostic radiology physics, nuclear medicine physics, radiation oncology physics, and health physics. To recognize the importance of radiation dosimetry to medical physics three new chapters have been added to the 14 chapters of the previous edition. Chapter 15 provides a general introduction to radiation dosimetry. Chapter 16 deals with absolute radiation dosimetry systems that establish absorbed dose or ...

  7. Radiation Therapy: Additional Treatment Options

    Science.gov (United States)

    ... Cancer Upper GI Cancers Search x FIND A RADIATION ONCOLOGIST CLOSE SNIPEND TREATMENT TYPES SNIPSTART Home / Treatment ... novel targeted therapies can act as radiosensitizers. Systemic Radiation Therapy Certain cancers may be treated with radioactive ...

  8. American Society for Radiation Oncology

    Science.gov (United States)

    ... for other cancer types View videos on radiation oncology Please Select an Action Read a news release ... This online career board is the premier radiation oncology recruitment tool, offering employers and job seekers an ...

  9. Radiation Injury to the Brain

    Science.gov (United States)

    ... Tumors Brain Tumors Brain Disorders AVMs Radiosurgery Gamma Knife Linac Radiotherapy Overview Childhood Brain Tumors IMRT Radiation Therapy Radiation Injury Treatment Day Making a Decision Centers of Excellence Publications Definitions Q & ...

  10. Resonance Radiation and Excited Atoms

    Science.gov (United States)

    Mitchell, Allan C. G.; Zemansky, Mark W.

    2009-06-01

    1. Introduction; 2. Physical and chemical effects connected with resonance radiation; 3. Absorption lines and measurements of the lifetime of the resonance state; 4. Collision processes involving excited atoms; 5. The polarization of resonance radiation; Appendix; Index.

  11. Conical electromagnetic radiation flux concentrator

    Science.gov (United States)

    Miller, E. R.

    1972-01-01

    Concentrator provides method of concentrating a beam of electromagnetic radiation into a smaller beam, presenting a higher flux density. Smaller beam may be made larger by sending radiation through the device in the reverse direction.

  12. Radiation Alert Immediate Disclosure Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Invocon's Radiation Alert Immediate Disclosure (RAID) system is a miniature, low-power, real-time, active radiation badge. It is designed for monitoring personnel,...

  13. Radiation Therapy for Testicular Cancer

    Science.gov (United States)

    ... Testicular Cancer Treating Testicular Cancer Radiation Therapy for Testicular Cancer Radiation therapy uses a beam of high-energy ... Testicular Cancer, by Type and Stage More In Testicular Cancer About Testicular Cancer Causes, Risk Factors, and Prevention ...

  14. An introduction to radiation protection

    CERN Document Server

    Martin, Alan; Beach, Karen; Cole, Peter

    2012-01-01

    The sixth edition of this established text takes the reader through the general background to the subject, the technical principles underlying the control of radiation hazards, radiation detection and measurement and the biological effects of radiation. These are followed by a consideration of radiation protection issues in the nuclear industry, the non-nuclear sector and the medical field. Further specialised topics include risk assessment, waste management and decommissioning, radiological incidents and emergencies, relevant legislation and organizational issues.

  15. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2015-01-01

    This fourth edition reflects recent major developments that have occurred in radiation detector materials, systems, and applications. It continues to provide the most practical and up-to-date introduction to radiation detector technology, proper measurement techniques, and analysis of results for engineers and scientists using radiation sources. New chapters emphasize the expanded use of radiation detection systems in nuclear non-proliferation, homeland security, and nuclear medicine. The book also discusses the correct ways to perform measurements following current health physics procedures.

  16. Pregnancy and Radiation Protection

    Science.gov (United States)

    Gerogiannis, J.; Stefanoyiannis, A. P.

    2010-01-01

    Several modalities are currently utilized for diagnosis and therapy, by appropriate application of x-rays. In diagnostic radiology, interventional radiology, radiotherapy, interventional cardiology, nuclear medicine and other specialties radiation protection of a pregnant woman as a patient, as well as a member of the operating personnel, is of outmost importance. Based on radiation risk, the termination of pregnancy is not justified if foetal doses are below 100 mGy. For foetal doses between 100 and 500 mGy, a decision is reached on a case by case basis. In Diagnostic Radiology, when a pregnant patient takes an abdomen CT, then an estimation of the foetus' dose is necessary. However, it is extremely rare for the dose to be high enough to justify an abortion. Radiographs of the chest and extremities can be done at any period of pregnancy, provided that the equipment is functioning properly. Usually, the radiation risk is lower than the risk of not undergoing a radiological examination. Radiation exposure in uterus from diagnostic radiological examinations is unlikely to result in any deleterious effect on the child, but the possibility of a radiation-induced effect can not be entirely ruled out. The effects of exposure to radiation on the foetus depend on the time of exposure, the date of conception and the absorbed dose. Finally, a pregnant worker can continue working in an x-ray department, as long as there is reasonable assurance that the foetal dose can be kept below 1 mGy during the pregnancy. Nuclear Medicine diagnostic examinations using short-lived radionuclides can be used for pregnant patient. Irradiation of the foetus results from placental transfer and distribution of radiopharmaceuticals in the foetal tissues, as well as from external irradiation from radioactivity in the mother's organ and tissues. As a rule, a pregnant patient should not undergo therapy with radionuclide, unless it is crucial for her life. In Radiotherapy, the patient, treating

  17. Space Radiation Cancer Risks

    Science.gov (United States)

    Cucinotta, Francis A.

    2007-01-01

    Space radiation presents major challenges to astronauts on the International Space Station and for future missions to the Earth s moon or Mars. Methods used to project risks on Earth need to be modified because of the large uncertainties in projecting cancer risks from space radiation, and thus impact safety factors. We describe NASA s unique approach to radiation safety that applies uncertainty based criteria within the occupational health program for astronauts: The two terrestrial criteria of a point estimate of maximum acceptable level of risk and application of the principle of As Low As Reasonably Achievable (ALARA) are supplemented by a third requirement that protects against risk projection uncertainties using the upper 95% confidence level (CL) in the radiation cancer projection model. NASA s acceptable level of risk for ISS and their new lunar program have been set at the point-estimate of a 3-percent risk of exposure induced death (REID). Tissue-averaged organ dose-equivalents are combined with age at exposure and gender-dependent risk coefficients to project the cumulative occupational radiation risks incurred by astronauts. The 95% CL criteria in practice is a stronger criterion than ALARA, but not an absolute cut-off as is applied to a point projection of a 3% REID. We describe the most recent astronaut dose limits, and present a historical review of astronaut organ doses estimates from the Mercury through the current ISS program, and future projections for lunar and Mars missions. NASA s 95% CL criteria is linked to a vibrant ground based radiobiology program investigating the radiobiology of high-energy protons and heavy ions. The near-term goal of research is new knowledge leading to the reduction of uncertainties in projection models. Risk projections involve a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. The current model for projecting space radiation

  18. Historical review of radiation research

    Energy Technology Data Exchange (ETDEWEB)

    Lindell, B. [Swedish Radiation Protection Inst., Stockholm (Sweden)

    1997-09-01

    The presentation reviews the history of radiation research beginning with the first findings and attempts for modelling of harmful effects of radiation, followed by the contamination of the environment, use of radiation epidemiology and concluding with the question of cancer generation. (26 refs.).

  19. Infrared Radiation from Rough Surface

    CERN Document Server

    Ayryan, E A; Oganesyan, K B

    2016-01-01

    We consider generation of diffusive radiation by a charged particle passing through a random stack of plates in the infrared region. Diffusive radiation originates due to multiple scattering of pseudophotons on the plates. To enhance the radiation intensity one needs to make the scattering more effective. For this goal we suggest to use materials with negative dielectric constant .

  20. Prevention of pelvic radiation disease

    Institute of Scientific and Technical Information of China (English)

    Lorenzo; Fuccio; Leonardo; Frazzoni; Alessandra; Guido

    2015-01-01

    Pelvic cancers are among the most frequently diagnosed cancers worldwide. Treatment of patients requires a multidisciplinary approach that frequently includes radiotherapy. Gastrointestinal(GI) radiation-induced toxicity is a major complication and the transient or long-term problems, ranging from mild to very severe, arising in non-cancerous tissues resulting from radiation treatment to a tumor of pelvic origin, are actually called as pelvic radiation disease. The incidence of pelvic radiation disease changes according to the radiation technique, the length of follow up, the assessmentmethod, the type and stage of cancer and several other variables. Notably, even with the most recent radiation techniques, i.e., intensity-modulated radiotherapy, the incidence of radiation-induced GI side effects is overall reduced but still not negligible. In addition, radiation-induced GI side effects can develop even after several decades; therefore, the improvement of patient life expectancy will unavoidably increase the risk of developing radiation-induced complications. Once developed, the management of pelvic radiation disease may be challenging. Therefore, the prevention of radiation-induced toxicity represents a reasonable way to avoid a dramatic drop of the quality of life of these patients. In the current manuscript we provide an updated and practical review on the best available evidences in the field of the prevention of pelvic radiation disease.

  1. Material Effectiveness for Radiation Shielding

    Science.gov (United States)

    2003-01-01

    Materials with a smaller mean atomic mass, such as lithium (Li) hydride and polyethylene, make the best radiation shields for astronauts. The materials have a higher density of nuclei and are better able to block incoming radiation. Also, they tend to produce fewer and less dangerous secondary particles after impact with incoming radiation.

  2. Radiation leakage from electromagnetic oven

    Directory of Open Access Journals (Sweden)

    Abdurrahman Khalil

    2015-10-01

    Results & Discussions: The measurements have been done at some houses in Erbil city, according to the source of background radiation exist before measuring data. Our data compared with standard safe range of radiation data. Results showed that there is radiation leak form all type of electromagnetic oven and all at the order of safety compared with standard value.

  3. Assessment of internal radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae Young; Chang, S. Y.; Lee, J. I.; Kim, J. S.; Song, M. Y. [Korea Atomic Energy Research Institute, Taejon (Korea)

    1999-05-01

    This report describes the contents and results for implementation of internal radiation monitoring programme, measurement of uranium lung deposition by lung counter and assessment of committed effective dose for radiation workers of KNFC. The aim of radiation protection was achieved by implementing this activity. 9 refs., 8 tabs. (Author)

  4. Acute Cerebrovascular Radiation Syndrome: Radiation Neurotoxicity , mechanisms of CNS radiation injury, advanced countermeasures for Radiation Protection of Central Nervous System.

    Science.gov (United States)

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key words: Cerebrovascular Acute Radiation Syndrome (Cv ARS), Radiation Neurotoxins (RNT), Neurotransmitters, Radiation Countermeasures, Antiradiation Vaccine (ArV), Antiradiation Blocking Antibodies, Antiradiation Antidote. Psychoneuroimmunology, Neurotoxicity. ABSTRACT: To review the role of Radiation Neurotoxins in triggering, developing of radiation induced central nervous system injury. Radiation Neurotoxins - rapidly acting blood toxic lethal agent, which activated after irradiation and concentrated, circulated in interstitial fluid, lymph, blood with interactions with cell membranes, receptors and cell compartments. Radiation Neurotoxins - biological molecules with high enzymatic activity and/or specific lipids and activated or modified after irradiation. The Radiation Neurotoxins induce increased permeability of blood vessels, disruption of the blood-brain barrier, blood-cerebrospinal fluid (CSF) barrier and developing severe disorder of blood macro- and micro-circulation. Principles of Radiation Psychoneuro-immunology and Psychoneuro-allergology were applied for determination of pathological processes developed after irradiation or selective administration of Radiation Neurotoxins to radiation naïve mammals. Effects of radiation and exposure to radiation can develop severe irreversible abnormalities of Central Nervous System, brain structures and functions. Antiradiation Vaccine - most effective, advanced methods of protection, prevention, mitigation and treatment and was used for of Acute Radiation Syndromes and elaboration of new technology for immune-prophylaxis and immune-protection against ϒ, Heavy Ion, Neutron irradiation. Results of experiments suggested that blocking, antitoxic, antiradiation antibodies can significantly reduce toxicity of Radiation Toxins. New advanced technology include active immune-prophylaxis with Antiradiation Vaccine and Antiradiation therapy that included specific blocking antibodies to Radiation Neurotoxins

  5. Doses from radiation exposure

    CERN Document Server

    Menzel, H G

    2012-01-01

    Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

  6. Radiation induced microbial pesticide

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Yup; Lee, Young Keun; Kim, Jae Sung; Kim, Jin Kyu; Lee, Sang Jae

    2000-01-01

    To control plant pathogenic fungi, 4 strains of bacteria (K1, K3, K4, YS1) were isolated from mushroom compost and hot spring. K4, K1, K3, YS1 strain showed wide antifungal spectrum and high antifungal activities against 13 kinds of fungi. Mutants of K1 and YS1 strains were induced by gamma-ray radiation and showed promising antifungal activities. These wild type and mutants showed resistant against more than 27 kinds of commercial pesticides among 30 kinds of commercial pesticides test particularly, YS1-1006 mutant strain showed resistant against hydrogen oxide. And mutants had increased antifungal activity against Botryoshaeria dothidea. These results suggested that radiation could be an useful method for the induction of functional mutants. (author)

  7. Radiation effects in glasses

    Energy Technology Data Exchange (ETDEWEB)

    Ehrt, D.; Vogel, W. (Otto-Schott-Inst., Chemische Fakultaet, Friedrich-Schiller-Univ., Jena (Germany))

    1992-03-01

    Glass was produced by man about 4000 years ago. The scientific exploration of glass is very young and closely connected with Jena. Fraunhofer, Goethe, Dobereiner, Abbe, Zeiss and Schott are famous names on this field. Both crystals and glasses are solids. However, there are fundamental differences in their properties and behavior. Glass is a thermodynamically unstable state and has a defect structure compared to the crystal. Glass and its properties are subject to a variety of changes under the influence of high energy radiation. In general, effects extend from the reduction of specific ions to the collapse of the entire network. Ultraviolet and X-ray radiation effects on UV-transmitting glasses will be discussed. (orig.).

  8. Radiative Bulk Viscosity

    CERN Document Server

    Chen, X

    2001-01-01

    Viscous resistance to changes in the volume of a gas arises when different degrees of freedom have different relaxation times. Collisions tend to oppose the resulting departures from equilibrium and, in so doing, generate entropy. Even for a classical gas of hard spheres, when the mean free paths or mean flight times of constituent particles are long, we find a nonvanishing bulk viscosity. Here we apply a method recently used to uncover this result for a classical rarefied gas to radiative transfer theory and derive an expression for the radiative stress tensor for a gray medium with absorption and Thomson scattering. We determine the transport coefficients through the calculation of the comoving entropy generation. When scattering dominates absorption, the bulk viscosity becomes much larger than either the shear viscosity or the thermal conductivity.

  9. Radiation detector with spodumene

    Energy Technology Data Exchange (ETDEWEB)

    D' Amorim, Raquel Aline P.O.; Lima, Hestia Raissa B.R.; Souza, Susana O. [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Fisica; Sasaki, Jose M., E-mail: sasaki@fisica.ufc.b [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Fisica; Caldas, Linda V.E., E-mail: lcaldas@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    In this work, {beta}-spodumene potentiality as a radiation detector was evaluated by making use of thermoluminescence (TL) and thermally stimulated exoelectron emission (TSEE) techniques. The pellets were obtained from the {beta}-spodumene powder mixed with Teflon followed by a sintering process of thermal treatments of 300 deg/30 min and 400 deg/1.5 h. The samples were irradiated in standard gamma radiation beams with doses between 5 Gy and 10 kGy. The TL emission curve showed a prominent peak at 160 deg and in the case of TSEE a prominent peak at 145 Celsius approximately. Initial results show that the material is promising for high-dose dosimetry. (author)

  10. ATLAS Transition Radiation Tracker

    CERN Multimedia

    2006-01-01

    The ATLAS transition radiation tracker is made of 300'000 straw tubes, up to 144cm long. Filled with a gas mixture and threaded with a wire, each straw is a complete mini-detector in its own right. An electric field is applied between the wire and the outside wall of the straw. As particles pass through, they collide with atoms in the gas, knocking out electrons. The avalanche of electrons is detected as an electrical signal on the wire in the centre. The tracker plays two important roles. Firstly, it makes more position measurements, giving more dots for the computers to join up to recreate the particle tracks. Also, together with the ATLAS calorimeters, it distinguishes between different types of particles depending on whether they emit radiation as they make the transition from the surrounding foil into the straws.

  11. Radiation protection research

    Energy Technology Data Exchange (ETDEWEB)

    Vanmarcke, H

    2002-04-01

    The objectives of the research in the field of radiation protection research performed at the Belgian Nuclear Research Centre SCK-CEN are (1) to elaborate and to improve methods and guidelines for the evaluation of restoration options for radioactively contaminated sites; (2) to develop, test and improve biosphere models for the performance assessment of radioactive waste disposal in near-surface or geological repositories; (3) to asses the impact of releases from nuclear or industrial installations; (4) to increase capabilities in mapping and surveying sites possibly or likely contaminated with enhanced levels of natural radiation; (5) to identify non nuclear industries producing NORM waste, to make an inventory of occurring problems and to propose feasible solutions or actions when required; (6) to maintain the know-how of retrospective radon measurements in real conditions and to assess radon decay product exposure by combining these techniques. Main achievements in these areas for 2001 are summarised.

  12. Genesis Radiation Environment

    Science.gov (United States)

    Minow, Joseph I.; Altstatt, Richard L.; Skipworth, William C.

    2007-01-01

    The Genesis spacecraft launched on 8 August 2001 sampled solar wind environments at L1 from 2001 to 2004. After the Science Capsule door was opened, numerous foils and samples were exposed to the various solar wind environments during periods including slow solar wind from the streamer belts, fast solar wind flows from coronal holes, and coronal mass ejections. The Survey and Examination of Eroded Returned Surfaces (SEERS) program led by NASA's Space Environments and Effects program had initiated access for the space materials community to the remaining Science Capsule hardware after the science samples had been removed for evaluation of materials exposure to the space environment. This presentation will describe the process used to generate a reference radiation Genesis Radiation Environment developed for the SEERS program for use by the materials science community in their analyses of the Genesis hardware.

  13. Radiation characterization summary :

    Energy Technology Data Exchange (ETDEWEB)

    Parma, Edward J.,; Quirk, Thomas J.; Lippert, Lance L.; Griffin, Patrick J; Naranjo, Gerald E.; Luker, Spencer Michael

    2013-04-01

    This document presents the facility-recommended characterization of the neutron, prompt gamma-ray, and delayed gamma-ray radiation fields in the Annular Core Research Reactor (ACRR) for the 44-inch-long lead-boron bucket in the central cavity on the 32-inch pedestal at the core centerline. The designation for this environment is ACRR-LB44-CC-32-cl. The neutron, prompt gamma-ray, and delayed gamma-ray energy spectra are presented as well as radial and axial neutron and gamma-ray flux profiles within the experiment area of the bucket. Recommended constants are given to facilitate the conversion of various dosimetry readings into radiation metrics desired by experimenters. Representative pulse and steady-state operations are presented with conversion examples.

  14. Radiation damage tolerant nanomaterials

    Directory of Open Access Journals (Sweden)

    I.J. Beyerlein

    2013-11-01

    Full Text Available Designing a material from the atomic level to achieve a tailored response in extreme conditions is a grand challenge in materials research. Nanostructured metals and composites provide a path to this goal because they contain interfaces that attract, absorb and annihilate point and line defects. These interfaces recover and control defects produced in materials subjected to extremes of displacement damage, impurity implantation, stress and temperature. Controlling radiation-induced-defects via interfaces is shown to be the key factor in reducing the damage and imparting stability in certain nanomaterials under conditions where bulk materials exhibit void swelling and/or embrittlement. We review the recovery of radiation-induced point defects at free surfaces and grain boundaries and stabilization of helium bubbles at interphase boundaries and present an approach for processing bulk nanocomposites containing interfaces that are stable under irradiation.

  15. Radiative corrections to DIS

    CERN Document Server

    Krasny, Mieczyslaw Witold

    2008-01-01

    Early deep inelastic scattering (DIS) experiments at SLAC discovered partons, identified them as quarks and gluons, and restricted the set of the candidate theories for strong interactions to those exhibiting the asymptotic freedom property. The next generation DIS experiments at FNAL and CERN confirmed the predictions of QCD for the size of the scaling violation effects in the nucleon structure functions. The QCD fits to their data resulted in determining the momentum distributions of the point-like constituents of nucleons. Interpretation of data coming from all these experiments and, in the case of the SLAC experiments, even an elaboration of the running strategies, would not have been possible without a precise understanding of the electromagnetic radiative corrections. In this note I recollect the important milestones, achieved in the period preceding the HERA era, in the high precision calculations of the radiative corrections to DIS, and in the development of the methods of their experimental control. ...

  16. HANARO radiation emergency plan

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Tai

    1997-10-15

    The emergency plan of HANARO (High-flux advanced Neutron Application Reactor) is prepared based on the Korea Atomic Law, the Civil Defence Law, Disaster Protection Law and the emergency related regulation guides such as the NUREG series from USNRC to ensure adequate response capabilities to the emergency event which would cause a significant risk to the KAERI staffs and the public near to the site. Periodic training and exercise for the reactor operators and emergency staffs will reduce accident risks and the release of radioactivities to the environment. The plan describes the organization and staff's duties in the radiation emergency, classification on the radiation accidents, urgent actions of reactor operators in the early state, emergency response activities, maintenance of emergency equipment, training and exercise to improve response capabilities against emergency accidents. (author). 1 tab., 5 figs.

  17. [Heavy particle radiation therapy].

    Science.gov (United States)

    Lozares, S; Mañeru, F; Pellejero, S

    2009-01-01

    The characteristics of radiation formed by heavy particles make it a highly useful tool for therapeutic use. Protons, helium nuclei or carbon ions are being successfully employed in radiotherapy installations throughout the world. This article sets out the physical and technological foundations that make these radiation particles suitable for attacking white volume, as well as the different ways of administering treatment. Next, the main clinical applications are described, which show the therapeutic advantages in some of the pathologies most widely employed in proton and hadron therapy centres at present. Under continuous study, the clinical use of heavy particles appears to be an enormously promising path of advance in comparison with classical technologies, both in tumour coverage and in reducing dosages in surrounding tissue.

  18. Radiation Induced Genomic Instability

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, William F.

    2011-03-01

    Radiation induced genomic instability can be observed in the progeny of irradiated cells multiple generations after irradiation of parental cells. The phenotype is well established both in vivo (Morgan 2003) and in vitro (Morgan 2003), and may be critical in radiation carcinogenesis (Little 2000, Huang et al. 2003). Instability can be induced by both the deposition of energy in irradiated cells as well as by signals transmitted by irradiated (targeted) cells to non-irradiated (non-targeted) cells (Kadhim et al. 1992, Lorimore et al. 1998). Thus both targeted and non-targeted cells can pass on the legacy of radiation to their progeny. However the radiation induced events and cellular processes that respond to both targeted and non-targeted radiation effects that lead to the unstable phenotype remain elusive. The cell system we have used to study radiation induced genomic instability utilizes human hamster GM10115 cells. These cells have a single copy of human chromosome 4 in a background of hamster chromosomes. Instability is evaluated in the clonal progeny of irradiated cells and a clone is considered unstable if it contains three or more metaphase sub-populations involving unique rearrangements of the human chromosome (Marder and Morgan 1993). Many of these unstable clones have been maintained in culture for many years and have been extensively characterized. As initially described by Clutton et al., (Clutton et al. 1996) many of our unstable clones exhibit persistently elevated levels of reactive oxygen species (Limoli et al. 2003), which appear to be due dysfunctional mitochondria (Kim et al. 2006, Kim et al. 2006). Interestingly, but perhaps not surprisingly, our unstable clones do not demonstrate a “mutator phenotype” (Limoli et al. 1997), but they do continue to rearrange their genomes for many years. The limiting factor with this system is the target – the human chromosome. While some clones demonstrate amplification of this chromosome and thus lend

  19. ATLAS Transitional Radiation Tracker

    CERN Multimedia

    ATLAS Outreach

    2006-01-01

    This colorful 3D animation is an excerpt from the film "ATLAS-Episode II, The Particles Strike Back." Shot with a bug's eye view of the inside of the detector. The viewer is taken on a tour of the inner workings of the transitional radiation tracker within the ATLAS detector. Subjects covered include what the tracker is used to measure, its structure, what happens when particles pass through the tracker, how it distinguishes between different types of particles within it.

  20. Radiation Bystander Effects Mechanism

    Directory of Open Access Journals (Sweden)

    Shokohzaman Soleymanifard

    2009-06-01

    Full Text Available Introduction: Radiation Induced Bystander Effect (RIBE which cause radiation effects in non-irradiated cells, has challenged the principle according to which radiation traversal through the nucleus of a cell is necessary for producing biological responses. What is the mechanism of this phenomenon? To have a better understanding of this rather ambiguous concept substantial number of original and reviewed article were carefully examined. Results: Irradiated cells release molecules which can propagate in cell environment and/or transmit through gap junction intercellular communication. These molecules can reach to non-irradiated cells and transmit bystander signals. In many investigations, it has been confirmed that these molecules are growth factors, cytokines, nitric oxide and free radicals like reactive oxygen species (ROS. Transmission of by stander signal to neighboring cells persuades them to produce secondary growth factors which in their turn cause further cell injuries. Some investigators suggest, organelles other than nucleus (mitochondria and cell membrane are the origin of these signals.  There is another opinion which suggests double strand breaks (DSB are not directly generated in bystander cells, rather they are due to smaller damage like single strand breaks which accumulate and end up to DSB. Although bystander mechanisms have not been exactly known, it can be confirmed that multiple mechanisms and various pathways are responsible for this effect. Cell type, radiation type, experimental conditions and end points identify the dominant mechanism. Conclusion: Molecules and pathways which are responsible for RIBE, also cause systemic responses to other non-irradiation stresses. So RIBE is a kind of systemic stress or innate immune responses, which are performed by cell microenvironment. Irradiated cells and their signals are components of microenvironment for creating bystander effects.

  1. Infrared Radiation of Flames

    Science.gov (United States)

    1961-10-01

    March 1960. 4. S. Silverman, G. A. Hornbeck, and R. C. Herman , J. Chem. Phys. 16 155 (1947). The Infrared Emission and Absorption or-the Carbon Monoxide...by Infrared Radiation. 9. S. Silverman and R. C. Herman , J. Opt. Soc. Am. 32, 216 (1949). The Infrared Emission Spectra of the Oxy- Hydrogen and Oxy...Press, 1961). 35. W. J, Pearce, Conference on Extremely High Temperatures, Fischer and Mansur , eds. (John Wiley & Sons, New York, 1958), p. 123. 36. M. P

  2. Radiation in Yolo County

    Science.gov (United States)

    Dickie, H.; Colwell, K.

    2013-12-01

    In today's post-nuclear age, there are many man-made sources of radioactivity, in addition to the natural background we expect from cosmic and terrestrial origins. While all atoms possess unstable isotopes, there are few that are abundant enough, energetic enough, and have long enough half-lives to pose a signicant risk of ionizing radiation exposure. We hypothesize a decreasing relative radiation measurement (in detected counts per minute [CPM]) at nine locations that might pose occupational or environmental hazard: 1. A supermarket produce aisle (living tissue has high concentration of 40K) 2. A hospital (medical imaging uses X-rays and radioactive dyes) 3. The electronics section of a superstore (high voltage electronics have the potential to produce ionizing radiation) 4. An electrical transformer (similar reasons) 5. An antique store (some ceramics and glazes use radioisotopes that are now outlawed) 6. A gasoline pump (processing and terrestrial isotope contamination might leave a radioactive residue) 7. A fertilized eld (phosphate rock contains uranium and thorium, in addition to potassium) 8. A house (hopefully mild background, but potential radon contamination) 9. A school (should be radiologically neutral) We tested the hypothesis by measuring 100 minutes of counts on a self-assembled MightyOhmTM Geiger counter at each location. Our results show that contrary to the hypothesized ordering, the house was the most radiologically active. We present possible explanations for the observed radiation levels, as well as possible sources of measurement error, possible consequences of prolonged exposure to the measured levels, and suggestions for decreasing exposure and environmental impact.

  3. Uninformed Hawking Radiation

    CERN Document Server

    Sakalli, I

    2014-01-01

    We show in detail that the Parikh-Wilczek tunneling method (PWTM), which was designed for resolving the information loss problem in Hawking radiation (HR)fails whenever the radiation occurs from an isothermal process. The PWTM aims to produce a non-thermal HR which adumbrates the resolution of the problem of unitarity in quantum mechanics (QM), and consequently the entropy (or information) conservation problem. The effectiveness of the method has been satisfactorily tested on numerous black holes (BHs). However, it has been shown that the isothermal HR, which results from the emission of the uncharged particles of the linear dilaton BH (LDBH) described in the Einstein-Maxwell-Dilaton (EMD) theory, the PWTM has vulnerability in having non-thermal radiation. In particular, we consider Painlev\\'{e}-Gullstrand coordinates (PGCs) and isotropic coordinates (ICs) in order to prove the aformentioned failure in the PWTM. While carrying out calculations in the ICs, we also highlight the effect of the refractive index o...

  4. Fanconi anemia and radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Asako; Komatsu, Kenshi [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

    1999-09-01

    Aplastic Fanconi anemia (FA) accompanying malformation was firstly reported in 1927. This review concerns the recent findings on FA. FA belongs to the chromosomal instability syndrome and its detailed molecular mechanism is still unknown. The disease has been defined to be highly sensitive to radiation, however, which is quite an important problem since irradiation with a large dose of radiation is required before its radical treatment (bone marrow transplantation). FA cells are also mitomycin C-sensitive and FA patients are said to be the mosaic of the sensitive and normal cells. This enables to classify FA into 8 types of A-H groups, whose genotypes (FAA-FAH, FANCA-FANCH) are becoming clear. However, the intracellular function of the FANC-expressed protein, although known to form a big complex, is not elucidated yet. There is an abnormality in DNA processing such as re-linkage of the double strand-broken DNA in FA cells. FA causal gene FANCG is found identical to XRCC9 which is associated to high sensitivity to radiation. Analysis of FANC genes will provide useful findings on molecular mechanism of DNA-repair. (K.H.)

  5. Stereotactic body radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Simon S. [Univ. Hospitals Seidman Cancer Center, Cleveland, OH (United States). Dept. of Radiation Oncology; Case Western Reserve Univ., Cleveland, OH (United States). Case Comprehensive Cancer Center; Teh, Bin S. [The Methodist Hospital Cancer Center and Research Institute, Houston, TX (United States). Weill Cornell Medical College; Lu, Jiade J. [National Univ. of Singapore (Singapore). Dept. of Radiation Oncology; Schefter, Tracey E. (eds.) [Colorado Univ., Aurora, CO (United States). Dept. of Radiation Oncology

    2012-11-01

    Comprehensive an up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. Examines in detail retrospective studies and prospective clinical trials for various organ sites from around the world. Written by world-renowned experts in SBRT from North America, Asia and Europe. Stereotactic body radiation therapy (SBRT) has emerged as an innovative treatment for various primary and metastatic cancers, and the past five years have witnessed a quantum leap in its use. This book provides a comprehensive and up-to-date account of the physical/technological, biological, and clinical aspects of SBRT. It will serve as a detailed resource for this rapidly developing treatment modality. The organ sites covered include lung, liver, spine, pancreas, prostate, adrenal, head and neck, and female reproductive tract. Retrospective studies and prospective clinical trials on SBRT for various organ sites from around the world are examined, and toxicities and normal tissue constraints are discussed. This book features unique insights from world-renowned experts in SBRT from North America, Asia, and Europe. It will be necessary reading for radiation oncologists, radiation oncology residents and fellows, medical physicists, medical physics residents, medical oncologists, surgical oncologists, and cancer scientists.

  6. Uninformed Hawking radiation

    Science.gov (United States)

    Sakalli, I.; Ovgun, A.

    2015-04-01

    We show in detail that the Parikh-Wilczek tunneling method (PWTM), which was designed for resolving the information loss problem in Hawking radiation (HR) fails whenever the radiation occurs from an isothermal process. The PWTM aims to produce a non-thermal HR which adumbrates the resolution of the problem of unitarity in quantum mechanics (QM), and consequently the entropy (or information) conservation problem. The effectiveness of the method has been satisfactorily tested on numerous black holes (BHs). However, it has been shown that the isothermal HR, which results from the emission of the uncharged particles of the linear dilaton BH (LDBH) described in the Einstein-Maxwell-Dilaton (EMD) theory, the PWTM has vulnerability in having non-thermal radiation. In particular, we consider Painlevé-Gullstrand coordinates (PGCs) and isotropic coordinates (ICs) in order to prove the aforementioned failure in the PWTM. While carrying out calculations in the ICs, we also highlight the effect of the refractive index on the null geodesics.

  7. Relativistic Radiation Mediated Shocks

    CERN Document Server

    Budnik, Ran; Sagiv, Amir; Waxman, Eli

    2010-01-01

    The structure of relativistic radiation mediated shocks (RRMS) propagating into a cold electron-proton plasma is calculated and analyzed. A qualitative discussion of the physics of relativistic and non relativistic shocks, including order of magnitude estimates for the relevant temperature and length scales, is presented. Detailed numerical solutions are derived for shock Lorentz factors $\\Gamma_u$ in the range $6\\le\\Gamma_u\\le30$, using a novel iteration technique solving the hydrodynamics and radiation transport equations (the protons, electrons and positrons are argued to be coupled by collective plasma processes and are treated as a fluid). The shock transition (deceleration) region, where the Lorentz factor $ \\Gamma $ drops from $ \\Gamma_u $ to $ \\sim 1 $, is characterized by high plasma temperatures $ T\\sim \\Gamma m_ec^2 $ and highly anisotropic radiation, with characteristic shock-frame energy of upstream and downstream going photons of a few~$\\times\\, m_ec^2$ and $\\sim \\Gamma^2 m_ec^2$, respectively.P...

  8. Microbeam radiation therapy

    Science.gov (United States)

    Laissue, Jean A.; Lyubimova, Nadia; Wagner, Hans-Peter; Archer, David W.; Slatkin, Daniel N.; Di Michiel, Marco; Nemoz, Christian; Renier, Michel; Brauer, Elke; Spanne, Per O.; Gebbers, Jan-Olef; Dixon, Keith; Blattmann, Hans

    1999-10-01

    The central nervous system of vertebrates, even when immature, displays extraordinary resistance to damage by microscopically narrow, multiple, parallel, planar beams of x rays. Imminently lethal gliosarcomas in the brains of mature rats can be inhibited and ablated by such microbeams with little or no harm to mature brain tissues and neurological function. Potentially palliative, conventional wide-beam radiotherapy of malignant brain tumors in human infants under three years of age is so fraught with the danger of disrupting the functional maturation of immature brain tissues around the targeted tumor that it is implemented infrequently. Other kinds of therapy for such tumors are often inadequate. We suggest that microbeam radiation therapy (MRT) might help to alleviate the situation. Wiggler-generated synchrotron x-rays were first used for experimental microplanar beam (microbeam) radiation therapy (MRT) at Brookhaven National Laboratory's National Synchrotron Light Source in the early 1990s. We now describe the progress achieved in MRT research to date using immature and adult rats irradiated at the European Synchrotron Radiation Facility in Grenoble, France, and investigated thereafter at the Institute of Pathology of the University of Bern.

  9. Sun and Other Types of Radiation

    Science.gov (United States)

    ... What Causes Cancer? Sun and Other Types of Radiation Learn about the different types of radiation and ... other diseases. Learn more here. Other Types of Radiation Exposure Not all types of radiation have been ...

  10. Radiation Therapy for Soft Tissue Sarcomas

    Science.gov (United States)

    ... Stage Soft Tissue Sarcoma Treating Soft Tissue Sarcomas Radiation Therapy for Soft Tissue Sarcomas Radiation therapy uses ... spread. This is called palliative treatment . Types of radiation therapy External beam radiation therapy: For this treatment, ...

  11. Lunar radiation environment

    Science.gov (United States)

    Schwadron, Nathan; Spence, Harlan; Wilson, Jody

    One of the goals of the CRaTER investigation is to characterize the radiation environment near the Moon in order to enable exploration. The state-of-the-art understanding developed thus far during the LRO mission is documented in a special issue of the Spaceweather Journal entitled “Space Weather: Building the observational foundation to deduce biological effects of space radiation” (Schwadron et al., 2013a). This recently published CRaTER work probes deeper into the physics of the radiation environment at the Moon. It motivates and provides the scientific basis for new investigations in the next phase of the LRO mission. The effects of Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs) range from chemical modification of the regolith, the generation of a radiation albedo that is increasingly illuminating chemical properties of the regolith, causing charging of the regolith and hazards to human explorers and robotic missions. Low-lunar orbit provides a platform for measuring SEP anisotropy over timescales of 2 hours both parallel and perpendicular to the ecliptic plane, and so far we have observed more than 18 SEP events with time-variable anisotropies during the LRO mission. Albedo proton maps of the Moon from CRaTER indicate that the flux of lunar albedo protons is correlated with elemental abundances at the lunar surface. The yield of albedo protons from the maria is 1% higher than the yield from the highlands, and there are localized peaks with even higher contrast (that may be co-located with peaks in trace elemental abundances as measured by the Lunar Prospector Gamma Ray Spectrometer). The Moon’s radiation environment both charges and affects the chemistry in the Moon’s polar regions, particularly in PSRs. This makes these regions a prime target for new CRaTER observations, since CRaTER measures GCRs and SEPs that penetrate the regolith down to 10s of cm. Thus, we review emerging discoveries from LRO/CRaTER’s remarkable exploration of

  12. Utrecht Radiative Transfer Courses

    Science.gov (United States)

    Rutten, R. J.

    2003-01-01

    The Utrecht course ``The Generation and Transport of Radiation'' teaches basic radiative transfer to second-year students. It is a much-expanded version of the first chapter of Rybicki & Lightman's ``Radiative Processes in Astrophysics''. After this course, students understand why intensity is measured per steradian, have an Eddington-Barbier feel for optically thick line formation, and know that scattering upsets LTE. The text is a computer-aided translation by Ruth Peterson of my 1992 Dutch-language course. My aim is to rewrite this course in non-computer English and make it web-available at some time. In the meantime, copies of the Peterson translation are made yearly at Uppsala -- ask them, not me. Eventually it should become a textbook. The Utrecht course ``Radiative Transfer in Stellar Atmospheres'' is a 30-hour course for third-year students. It treats NLTE line formation in plane-parallel stellar atmospheres at a level intermediate between the books by Novotny and Boehm-Vitense, and Mihalas' ``Stellar Atmospheres''. After this course, students appreciate that epsilon is small, that radiation can heat or cool, and that computers have changed the field. This course is web-available since 1995 and is regularly improved -- but remains incomplete. Eventually it should become a textbook. The three Utrecht exercise sets ``Stellar Spectra A: Basic Line Formation'', ``Stellar Spectra B: LTE Line Formation'', and ``Stellar Spectra C: NLTE Line Formation'' are IDL-based computer exercises for first-year, second-year, and third-year students, respectively. They treat spectral classification, Saha-Boltzmann population statistics, the curve of growth, the FAL-C solar atmosphere model, the role of H-minus in the solar continuum, LTE formation of Fraunhofer lines, inversion tactics, the Feautrier method, classical lambda iteration, and ALI computation. The first two sets are web-available since 1998; the third will follow. Acknowledgement. Both courses owe much to previous

  13. Chapter 1: Direct Normal Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Myer, Daryl R.

    2016-04-15

    This chapter addresses the quantitative and qualitative aspects of the solar resource, the direct solar radiation. It discusses the total or integrated broadband direct beam extraterrestrial radiation (ETR). This total integrated irradiance is comprised of photons of electromagnetic radiation. The chapter also discusses the impact of the atmosphere and its effect upon the direct normal irradiance (DNI) beam radiation. The gases and particulates present in the atmosphere traversed by the direct beam reflect, absorb, and scatter differing spectral regions and proportions of the direct beam, and act as a variable filter. Knowledge of the available broadband DNI beam radiation resource data is essential in designing a concentrating photovoltaic (CPV) system. Spectral variations in the DNI beam radiation affect the performance of a CPV system depending on the solar cell technology used. The chapter describes propagation and scattering processes of circumsolar radiation (CSR), which includes the Mie scattering from large particles.

  14. New approaches to radiation protection

    Directory of Open Access Journals (Sweden)

    Eliot Michael Rosen

    2015-01-01

    Full Text Available Radioprotectors are compounds that protect against radiation injury when given prior to radiation exposure. Mitigators can protect against radiation injury when given after exposure but before symptoms appear. Radioprotectors and mitigators can potentially improve the outcomes of radiotherapy for cancer treatment by allowing higher doses of radiation and/or reduced damage to normal tissues. Such compounds can also potentially counteract the effects of accidental exposure to radiation or deliberate exposure (eg., nuclear reactor meltdown, dirty bomb, or nuclear bomb explosion; hence the are called radiation countermeasures. Here we will review the general principles of radiation injury and protection and describe selected examples of radioprotectors/mitigators ranging from small molecules to proteins to cell-based treatments. We will emphasize agents that are in more advanced stages of development.

  15. DOE 2012 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-10-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site.

  16. DOE 2011 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2012-12-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2011 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.

  17. Radiation shielding for diagnostic radiology.

    Science.gov (United States)

    Martin, Colin J

    2015-07-01

    Scattered radiation makes up the majority of the stray radiation field around an X-ray unit. The scatter is linked to the amount of radiation incident on the patient. It can be estimated from quantities used to assess patient dose such as the kerma-area product, and factors have been established linking this to levels of scattered radiation for radiography and fluoroscopy. In radiography shielding against primary radiation is also needed, but in other modalities this is negligible, as the beam is intercepted by the image receptor. In the same way scatter from CT can be quantified in terms of dose-length product, but because of higher radiation levels, exposure to tertiary scatter from ceilings needs to be considered. Transmission requirements are determined from comparisons between calculated radiation levels and agreed dose criteria, taking into account the occupancy of adjacent areas. Thicknesses of shielding material required can then be calculated from simple equations.

  18. Radiation control standards and procedures

    Energy Technology Data Exchange (ETDEWEB)

    1956-12-14

    This manual contains the Radiation Control Standards'' and Radiation Control Procedures'' at Hanford Operations which have been established to provide the necessary control radiation exposures within Irradiation Processing Department. Provision is also made for including, in the form of Bulletins'', other radiological information of general interest to IPD personnel. The purpose of the standards is to establish firm radiological limits within which the Irradiation Processing Department will operate, and to outline our radiation control program in sufficient detail to insure uniform and consistent application throughout all IPD facilities. Radiation Control Procedures are intended to prescribe the best method of accomplishing an objective within the limitations of the Radiation Control Standards. A procedure may be changed at any time provided the suggested changes is generally agreeable to management involved, and is consistent with department policies and the Radiation Control Standards.

  19. Non-LTE Radiation Transport in High Radiation Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Scott, H A

    2005-01-07

    A primary goal of numerical radiation transport is obtaining a self-consistent solution for both the radiation field and plasma properties. Obtaining such a solution requires consideration of the coupling between the radiation and the plasma. The different characteristics of this coupling for continuum and line radiation have resulted in two separate sub-disciplines of radiation transport with distinct emphases and computational techniques. LTE radiation transfer focuses on energy transport and exchange through broadband radiation, primarily affecting temperature and ionization balance. Non-LTE line transfer focuses on narrowband radiation and the response of individual level populations, primarily affecting spectral properties. Many high energy density applications, particularly those with high-Z materials, incorporate characteristics of both these regimes. Applications with large radiation fields including strong line components require a non-LTE broadband treatment of energy transport and exchange. We discuss these issues and present a radiation transport treatment which combines features of both types of approaches by explicitly incorporating the dependence of material properties on both temperature and radiation fields. The additional terms generated by the radiation dependence do not change the character of the system of equations and can easily be added to a numerical transport implementation. A numerical example from a Z-pinch application demonstrates that this method improves both the stability and convergence of the calculations. The information needed to characterize the material response to radiation is closely related to that used by the Linear Response Matrix (LRM) approach to near-LTE simulation, and we investigate the use of the LRM for these calculations.

  20. Engineering calculations in radiative heat transfer

    CERN Document Server

    Gray, W A; Hopkins, D W

    1974-01-01

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

  1. Radiation exposure to personnel involved in bone scans for horses with technetium 99m-diphosphonat; Strahlenexposition des Personals bei der Skelettszintigrafie mit Technetium-99m-Diphosphonat beim Pferd

    Energy Technology Data Exchange (ETDEWEB)

    Sommerfeld, Theresa Christine

    2016-07-01

    radiation experts the impact of the so called ''beam hardening effect'' under the lead shield appears in opposed discussions. Therefore each medical center handles the use of lead shields individually, a matter of fact which was also mirrored by the survey of this dissertation. With regards to lower radiation doses the ''Hypothesis of Hormesis'' is contradictory to the ICRP rules, which cover the ''Linear-No-Threshold-Model'' and the ''ALARA-Principle''. As of today none of the before mentioned principles are confirmed by scientific investigations. Hence, veterinarian personnel shall reduce the dose consumption by obeying the three main principles for radiation protection: ''Distance'', ''Shielding'' and ''Time of Exposure''.

  2. 08 Case report 356

    African Journals Online (AJOL)

    Marinda

    Mediastinitis after oesophagoscopy: A case report. ABSTRACT. A 50-year-old male presented with signs and symptoms of oesophageal perforation after a biopsy. Suggestive symptoms and signs were pain in the neck radiating to the back, a rise in temperature ... On the second postoperative day his blood pressure was still.

  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. Chronic radiation syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Akleyev, Alexander V. [Urals Research Centre for Radiation Medicine, Chelyabinsk (Russian Federation). Clinical Dept.

    2014-04-01

    Comprehensive analysis of chronic radiation syndrome, covering epidemiology, pathogenesis, pathoanatomy, diagnosis and treatment. Based on observations in a unique sample of exposed residents of the Techa riverside villages in the Urals. Casts new light on the condition. Of value for all practitioners and researchers with an interest in chronic radiation syndrome. This book covers all aspects of chronic radiation syndrome (CRS) based on observations in a unique sample of residents of the Techa riverside villages in the southern Urals who were exposed to radioactive contamination in the 1950s owing to releases of liquid radioactive wastes from Mayak Production Association, which produced plutonium for weapons. In total, 940 cases of CRS were diagnosed in this population and these patients were subjected to detailed analysis. The opening chapters address the definition and classification of CRS, epidemiology and pathogenesis, covering molecular and cellular mechanisms, radioadaptation, and the role of tissue reactions. The pathoanatomy of CRS during the development and recovery stages is discussed for all organ systems. Clinical manifestations of CRS at the different stages are then described in detail and the dynamics of hematopoietic changes are thoroughly examined. In the following chapters, principles of diagnosis (including assessment of the exposure doses to critical organs) and differential diagnosis from a wide range of other conditions are discussed and current and potential treatment options, described. The medical and social rehabilitation of persons with CRS is also covered. This book, which casts new light on the condition, will be of value for all practitioners and researchers with an interest in CRS.

  5. Radiative Equilibrium and Temperature Correction in Monte Carlo Radiation Transfer

    OpenAIRE

    Bjorkman, J. E.; Wood, Kenneth

    2001-01-01

    We describe a general radiative equilibrium and temperature correction procedure for use in Monte Carlo radiation transfer codes with sources of temperature-independent opacity, such as astrophysical dust. The technique utilizes the fact that Monte Carlo simulations track individual photon packets, so we may easily determine where their energy is absorbed. When a packet is absorbed, it heats a particular cell within the envelope, raising its temperature. To enforce radiative equilibrium, the ...

  6. ALICE Transition Radiation Detector

    CERN Multimedia

    Pachmayer, Y

    2013-01-01

    The Transition Radiation Detector (TRD) is the main electron detector in ALICE. In conduction with the TPC and the ITS, it provides the necessary electron identification capability to study: - Production of light and heavy vector mesons as well as the continuum in the di-electron channel, - Semi leptonic decays of hadrons with open charm and open beauty via the single-electron channel using the displaced vertex information provided by the ITS, - Correlated DD and BB pairs via coincidences of electrons in the central barrel and muons in the forward muon arm, - Jets with high Pτ tracks in one single TRD stack.

  7. The space radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, D.E.

    1997-04-30

    There are three primary sources of space radiation: galactic cosmic rays (GCR), trapped belt radiation, and solar particle events (SPE). All are composed of ions, the nuclei of atoms. Their energies range from a few MeV u{sup -1} to over a GeV u{sup -1}. These ions can fragment when they interact with spacecraft materials and produce energetic neutrons and ions of lower atomic mass. Absorbed dose rates inside a typical spacecraft (like the Space Shuttle) in a low inclination (28.5 degrees) orbit range between 0.05 and 2 mGy d{sup -1} depending on the altitude and flight inclination (angle of orbit with the equator). The quality factor of radiation in orbit depends on the relative contributions of trapped belt radiation and GCR, and the dose rate varies both with orbital altitude and inclination. The corresponding equivalent dose rate ranges between 0.1 and 4 mSv d{sup -1}. In high inclination orbits, like that of the Mir Space Station and as is planned for the International Space Station, blood-forming organ (BFO) equivalent dose rates as high as 1.5 mSv d{sup -1}. Thus, on a 1 y mission, a crew member could obtain a total dose of 0.55 Sv. Maximum equivalent dose rates measured in high altitude passes through the South Atlantic Anomaly (SAA) were 10 mSv h{sup -1}. For an interplanetary space mission (e.g., to Mars) annual doses from GCR alone range between 150 mSv y{sup -1} at solar maximum and 580 mSv y{sup -1} at solar minimum. Large SPE, like the October 1989 series, are more apt to occur in the years around solar maximum. In free space, such an event could contribute another 300 mSv, assuming that a warning system and safe haven can be effectively used with operational procedures to minimize crew exposures. Thus, the total dose for a 3 y mission to Mars could exceed 2 Sv.

  8. Chronic radiation myelitis.

    Science.gov (United States)

    Fitzgerald, R H; Marks, R D; Wallace, K M

    1982-08-01

    From March 1971 to September 1973, 200 patients with primary bronchogenic carcinoma received 4,000 rad (40 Gy) by means of split-course accelerated fractionation. Forty-five patients (22.5%) survived more than 11 months; and of these, 6 (13.3%) were found to have progressive myelitis. Recent reports indicate that rapid fractionation is preferred in some centers and may be undergoing a resurgence. The authors review their experience with this technique and the current understanding of the factors which affect the development of radiation myelitis.

  9. Cosmic Tachyon Background Radiation

    CERN Document Server

    Tomaschitz, R

    1999-01-01

    The equilibrium statistical mechanics of a background radiation of superluminal particles is investigated, based on a vectorial wave equation for tachyons of the Proca type. The partition function, the spectral energy density, and the various thermodynamic variables of an ideal Bose gas of tachyons in an open Robertson-Walker cosmology are derived. The negative mass square in the wave equation changes the frequency scaling in the Rayleigh-Jeans law, and there are also significant changes in the low temperature regime as compared to the microwave background, in particular in the caloric and thermal equations of state.

  10. Radiation damage in graphite

    CERN Document Server

    Simmons, John Harry Walrond

    1965-01-01

    Nuclear Energy, Volume 102: Radiation Damage in Graphite provides a general account of the effects of irradiation on graphite. This book presents valuable work on the structure of the defects produced in graphite crystals by irradiation. Organized into eight chapters, this volume begins with an overview of the description of the methods of manufacturing graphite and of its physical properties. This text then presents details of the method of setting up a scale of irradiation dose. Other chapters consider the effect of irradiation at a given temperature on a physical property of graphite. This

  11. Danfos: Thermostatic Radiator Valves

    DEFF Research Database (Denmark)

    Gregersen, Niels; Oliver, James; Hjorth, Poul G.

    2000-01-01

    This problem deals with modelling the flow through a typical Danfoss thermostatic radiator valve.Danfoss is able to employ Computational Fluid Dynamics (CFD) in calculations of the capacity of valves, but an experienced engineer can often by rules of thumb "guess" the capacity, with a precision...... similar to the one achieved by the expensive and time-consuming CFD calculations. So CFD is only used in case of entirely new designs or where a very detailed knowledge of the flow is required. Even though rules of thumb are useful for those, who have developed them, Danfoss needs an objective and general...... method that can be used to predict the performance of valves....

  12. Microstructured silicon radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Okandan, Murat; Derzon, Mark S.; Draper, Bruce L.

    2017-03-14

    A radiation detector comprises a silicon body in which are defined vertical pores filled with a converter material and situated within silicon depletion regions. One or more charge-collection electrodes are arranged to collect current generated when secondary particles enter the silicon body through walls of the pores. The pores are disposed in low-density clusters, have a majority pore thickness of 5 .mu.m or less, and have a majority aspect ratio, defined as the ratio of pore depth to pore thickness, of at least 10.

  13. Radiative Augmented Combustion.

    Science.gov (United States)

    1985-08-12

    86-0085 In 00I to RADIATIVE AUGMENTED COMBUSTION MOSHE LAVID M.L. ENERGIA , INC. P.O. BOX 1468 1 PRINCETON, NEW JERSEY 08542 AUGUST 1985 *.. plo...Combustion conducted at M.L. ENERGIA . It is funded by the Air Force Office of Scientific Research under Contract No. F49620-83-C-0133, with Dr. J.M...reported. It covers the second year of the contract, from July 15, 1984 through July 14, 1985. The work was performed at ENERGIA , Princeton, New Jersey

  14. Radiation protection considerations

    CERN Document Server

    Adorisio, C; Urscheler, C; Vincke, H

    2015-01-01

    This chapter summarizes the legal Radiation Protection (RP) framework to be considered in the design of HiLumi LHC. It details design limits and constraints, dose objectives and explains how the As Low As Reasonably Achievable (ALARA) approach is formalized at CERN. Furthermore, features of the FLUKA Monte Carlo code are summarized that are of relevance for RP studies. Results of FLUKA simulations for residual dose rates during Long Shutdown 1 (LS1) are compared to measurements demonstrating good agreement and providing proof for the accuracy of FLUKA predictions for future shutdowns. Finally, an outlook for the residual dose rate evolution until LS3 is given.

  15. Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture

    Energy Technology Data Exchange (ETDEWEB)

    Scott Wilde, Raymond Keegan

    2008-07-01

    The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

  16. METHODOLOGICAL NOTES: Radiation damping forces and radiation from charged particles

    Science.gov (United States)

    Klepikov, N. P.

    1985-06-01

    A review of the literature on the radiation reaction force on a charged particle shows that the expression given for this force obtained by Lorentz, Abraham, and Dirac is in physically reasonable agreement with the radiation of energy, momentum, and angular momentum, and is successfully used in investigating the motion of particles in a field. A selection of physical solutions by the methods presented herein guarantees that the conservation laws are satisfied. In the first approximation, which is the only one utilized in the majority of physical situations, radiation damping does not depend on assumptions concerning the structure of the charge of the particle. A theory is presented of the losses of energy, momentum and angular momentum by a system of charged particles in the course of their moving together taking into account the external field, the radiation damping forces, and the retarded Lienard-Wiechert forces. Formulas are given for the spectral and angular distribution of the radiation from a system of particles. The concept of a center of a system of events with relativistic particles is utilized in constructing a system of equations for finding the angular momenta of the electromagnetic waves radiated by particles of the system. The angular distribution and the total intensity of the radiation from a system of particles at an arbitrary instant of time is obtained. Using the example of the joint synchrotron radiation from two particles the consistency of all three approaches to the radiation from a system of particles is demonstrated.

  17. Radiation damage in biomolecular systems

    CERN Document Server

    Fuss, Martina Christina

    2012-01-01

    Since the discovery of X-rays and radioactivity, ionizing radiations have been widely applied in medicine both for diagnostic and therapeutic purposes. The risks associated with radiation exposure and handling led to the parallel development of the field of radiation protection. Pioneering experiments done by Sanche and co-workers in 2000 showed that low-energy secondary electrons, which are abundantly generated along radiation tracks, are primarily responsible for radiation damage through successive interactions with the molecular constituents of the medium. Apart from ionizing processes, which are usually related to radiation damage, below the ionization level low-energy electrons can induce molecular fragmentation via dissociative processes such as internal excitation and electron attachment. This prompted collaborative projects between different research groups from European countries together with other specialists from Canada,  the USA and Australia. This book summarizes the advances achieved by these...

  18. DOE 2008 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-10-01

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE. The DOE 2008 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. This report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  19. DOE 2009 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-09-01

    The U.S. Department of Energy (DOE) Office of Corporate Safety Analysis (HS-30) within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The DOE 2009 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  20. Sound radiation from finite surfaces

    DEFF Research Database (Denmark)

    Brunskog, Jonas

    2013-01-01

    A method to account for the effect of finite size in acoustic power radiation problem of planar surfaces using spatial windowing is developed. Cremer and Heckl presents a very useful formula for the power radiating from a structure using the spatially Fourier transformed velocity, which combined...... with spatially windowing of a plane waves can be used to take into account the finite size. In the present paper, this is developed by means of a radiation impedance for finite surfaces, that is used instead of the radiation impedance for infinite surfaces. In this way, the spatial windowing is included...... in the radiation formula directly, and no pre-windowing is needed. Examples are given for the radiation efficiency, and the results are compared with results found in the literature....

  1. The physics of radiation therapy

    CERN Document Server

    Khan, Faiz M

    2009-01-01

    Dr. Khan's classic textbook on radiation oncology physics is now in its thoroughly revised and updated Fourth Edition. It provides the entire radiation therapy team—radiation oncologists, medical physicists, dosimetrists, and radiation therapists—with a thorough understanding of the physics and practical clinical applications of advanced radiation therapy technologies, including 3D-CRT, stereotactic radiotherapy, HDR, IMRT, IGRT, and proton beam therapy. These technologies are discussed along with the physical concepts underlying treatment planning, treatment delivery, and dosimetry. This Fourth Edition includes brand-new chapters on image-guided radiation therapy (IGRT) and proton beam therapy. Other chapters have been revised to incorporate the most recent developments in the field. This edition also features more than 100 full-color illustrations throughout.

  2. Gravitational scattering of electromagnetic radiation

    Science.gov (United States)

    Brooker, J. T.; Janis, A. I.

    1980-01-01

    The scattering of electromagnetic radiation by linearized gravitational fields is studied to second order in a perturbation expansion. The incoming electromagnetic radiation can be of arbitrary multipole structure, and the gravitational fields are also taken to be advanced fields of arbitrary multipole structure. All electromagnetic multipole radiation is found to be scattered by gravitational monopole and time-varying dipole fields. No case has been found, however, in which any electromagnetic multipole radiation is scattered by gravitational fields of quadrupole or higher-order multipole structure. This lack of scattering is established for infinite classes of special cases, and is conjectured to hold in general. The results of the scattering analysis are applied to the case of electromagnetic radiation scattered by a moving mass. It is shown how the mass and velocity may be determined by a knowledge of the incident and scattered radiation.

  3. Quantum optical dipole radiation fields

    CERN Document Server

    Stokes, Adam

    2016-01-01

    We introduce quantum optical dipole radiation fields defined in terms of photon creation and annihilation operators. These fields are identified through their spatial dependence, as the components of the total fields that survive infinitely far from the dipole source. We use these radiation fields to perturbatively evaluate the electromagnetic radiated energy-flux of the excited dipole. Our results indicate that the standard interpretation of a bare atom surrounded by a localised virtual photon cloud, is difficult to sustain, because the radiated energy-flux surviving infinitely far from the source contains virtual contributions. It follows that there is a clear distinction to be made between a radiative photon defined in terms of the radiation fields, and a real photon, whose identification depends on whether or not a given process conserves the free energy. This free energy is represented by the difference between the total dipole-field Hamiltonian and its interaction component.

  4. DOE 2010 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2011-11-01

    The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE.* The DOE 2010 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with DOE Part 835 dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past 5 years.

  5. Future Synchrotron Radiation Sources

    CERN Document Server

    Winick, Herman

    2003-01-01

    Sources of synchrotron radiation (also called synchrotron light) and their associated research facilities have experienced a spectacular growth in number, performance, and breadth of application in the past two to three decades. In 1978 there were eleven electron storage rings used as light sources. Three of these were small rings, all below 500 mega-electron volts (MeV), dedicated to this purpose; the others, with energy up to 5 giga-electron volts (GeV), were used parasitically during the operation of the ring for high energy physics research. In addition, at that time synchrotron radiation from nine cyclic electron synchrotrons, with energy up to 5 GeV, was also used parasitically. At present no cyclic synchrotrons are used, while about 50 electron storage rings are in operation around the world as fully dedicated light sources for basic and applied research in a wide variety of fields. Among these fields are structural molecular biology, molecular environmental science, materials, analytic chemistry, micr...

  6. Radiation accident grips Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, L.

    1987-11-20

    On 13 September two young scavengers in Goiania, Brazil, removed a stainless steel cylinder from a cancer therapy machine in an abandoned clinic, touching off a radiation accident second only to Chernobyl in its severity. On 18 September they sold the cylinder, the size of a 1-gallon paint can, to a scrap dealer for $25. At the junk yard an employee dismantled the cylinder and pried open the platinum capsule inside to reveal a glowing blue salt-like substance - 1400 curies of cesium-137. Fascinated by the luminescent powder, several people took it home with them. Some children reportedly rubbed in on their bodies like carnival glitter - an eerie image of how wrong things can go when vigilance over radioactive materials lapses. In all, 244 people in Goiania, a city of 1 million in central Brazil, were contaminated. The eventual toll, in terms of cancer or genetic defects, cannot yet be estimated. Parts of the city are cordoned off as radiation teams continue washing down buildings and scooping up radioactive soil. The government is also grappling with the political fallout from the accident.

  7. Space radiation studies

    Science.gov (United States)

    1989-01-01

    Two Active Radiation Dosimeters (ARD's) flown on Spacelab 1, performed without fault and were returned to Space Science Laboratory, MSFC for recalibration. During the flight, performance was monitored at the Huntsville Operations Center (HOSC). Despite some problems with the Shuttle data system handling the verification flight instrumentation (VFI), it was established that the ARD's were operating normally. Postflight calibrations of both units determined that sensitivities were essentially unchanged from preflight values. Flight tapes were received for approx. 60 percent of the flight and it appears that this is the total available. The data was analyzed in collaboration with Space Science Laboratory, MSFC. Also, the Nuclear Radiation Monitor (NRM) was assembled and tested at MSFC. Support was rendered in the areas of materials control and parts were supplied for the supplementary heaters, dome gas-venting device and photomultiplier tube housing. Performance characteristics of some flight-space photomultipliers were measured. The NRM was flown on a balloon-borne test flight and subsequently performed without fault on Spacelab-2. This data was analyzed and published.

  8. Radiation sterilization of ketoprofen

    Energy Technology Data Exchange (ETDEWEB)

    Katusin-Razem, Branka [Ruder Boskovic Institute, P.O.B 180, Zagreb 10000 (Croatia)]. E-mail: brazem@irb.hr; Hamitouche, Katia [Centre de Recherche et Developpement Saidal, El Harrach (Algeria); Maltar-Strmecki, Nadica [Faculty of Veterinary Medicine, University of Zagreb, Zagreb 10000 (Croatia); Kos, Karmen [Belupo Pharmaceutical Works, Koprivnica 48000 (Croatia); Pucic, Irina [Ruder Boskovic Institute, P.O.B 180, Zagreb 10000 (Croatia); Britvic-Budicin, Smiljana [Ruder Boskovic Institute, P.O.B 180, Zagreb 10000 (Croatia); Razem, Dusan [Ruder Boskovic Institute, P.O.B 180, Zagreb 10000 (Croatia)

    2005-06-01

    Radiation sterilization of ketoprofen (KP) dry powder was investigated by selected physico-chemical methods. High-performance liquid chromatography, ultraviolet spectrophotometry, infrared spectrophotometry, differential scanning calorimetry, X-ray diffraction and electron spin resonance spectroscopy did not show any significant degradation at sterilization dose 25 kGy. To determine the nature, extent and direction of radiation-induced changes, KP was irradiated to extremely high doses, much higher than necessary to achieve sterility. The irradiated KP did not show any difference of XRD patterns up to 200 kGy; with DSC and IR some changes were detected only above 1000 and 2000 kGy, respectively; HPLC has shown about 5% destruction at 2000 kGy. Acetyl benzophenon (AcBph) was generated by irradiation with G(AcBph)=(1.6{+-}0.1)x10{sup -8} mol J{sup -1}. Ames test has shown no mutagenicity of KP irradiated with 3000 kGy or of the oily mixture of radiolytic products isolated from it. Solid KP has proven to be very stable on irradiation, and irradiation has been found to be a suitable method for its sterilization.

  9. Radiation sterilization of ketoprofen

    Science.gov (United States)

    Katušin-Ražem, Branka; Hamitouche, Katia; Maltar-Strmečki, Nadica; Kos, Karmen; Pucić, Irina; Britvić-Budicin, Smiljana; Ražem, Dušan

    2005-06-01

    Radiation sterilization of ketoprofen (KP) dry powder was investigated by selected physico-chemical methods. High-performance liquid chromatography, ultraviolet spectrophotometry, infrared spectrophotometry, differential scanning calorimetry, X-ray diffraction and electron spin resonance spectroscopy did not show any significant degradation at sterilization dose 25 kGy. To determine the nature, extent and direction of radiation-induced changes, KP was irradiated to extremely high doses, much higher than necessary to achieve sterility. The irradiated KP did not show any difference of XRD patterns up to 200 kGy; with DSC and IR some changes were detected only above 1000 and 2000 kGy, respectively; HPLC has shown about 5% destruction at 2000 kGy. Acetyl benzophenon (AcBph) was generated by irradiation with G(AcBph)=(1.6±0.1)×10 -8 mol J -1. Ames test has shown no mutagenicity of KP irradiated with 3000 kGy or of the oily mixure of radiolytic products isolated from it. Solid KP has proven to be very stable on irradiation, and irradiation has been found to be a suitable method for its sterilization.

  10. Ultraviolet radiation and cyanobacteria.

    Science.gov (United States)

    Rastogi, Rajesh Prasad; Sinha, Rajeshwar P; Moh, Sang Hyun; Lee, Taek Kyun; Kottuparambil, Sreejith; Kim, Youn-Jung; Rhee, Jae-Sung; Choi, Eun-Mi; Brown, Murray T; Häder, Donat-Peter; Han, Taejun

    2014-12-01

    Cyanobacteria are the dominant photosynthetic prokaryotes from an ecological, economical, or evolutionary perspective, and depend on solar energy to conduct their normal life processes. However, the marked increase in solar ultraviolet radiation (UVR) caused by the continuous depletion of the stratospheric ozone shield has fueled serious concerns about the ecological consequences for all living organisms, including cyanobacteria. UV-B radiation can damage cellular DNA and several physiological and biochemical processes in cyanobacterial cells, either directly, through its interaction with certain biomolecules that absorb in the UV range, or indirectly, with the oxidative stress exerted by reactive oxygen species. However, cyanobacteria have a long history of survival on Earth, and they predate the existence of the present ozone shield. To withstand the detrimental effects of solar UVR, these prokaryotes have evolved several lines of defense and various tolerance mechanisms, including avoidance, antioxidant production, DNA repair, protein resynthesis, programmed cell death, and the synthesis of UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin. This study critically reviews the current information on the effects of UVR on several physiological and biochemical processes of cyanobacteria and the various tolerance mechanisms they have developed. Genomic insights into the biosynthesis of MAAs and scytonemin and recent advances in our understanding of the roles of exopolysaccharides and heat shock proteins in photoprotection are also discussed.

  11. [Stereotactic radiation therapy].

    Science.gov (United States)

    Aristu, J J; Ciérvide, R; Guridi, J; Moreno, M; Arbea, L; Azcona, J D; Ramos, L I; Zubieta, J L

    2009-01-01

    Stereotactic radiotherapy is a form of external radiotherapy that employs a system of three dimensional coordinates independent of the patient for the precise localisation of the lesion. It also has the characteristic that the radiation beams are conformed and precise, and converge on the lesion, making it possible to administer very high doses of radiotherapy without increasing the radiation to healthy adjacent organs or structures. When the procedure is carried out in one treatment session it is termed radiosurgery, and when administered over several sessions it is termed stereotactic radiotherapy. Special systems of fixing or immobilising the patient (guides or stereotactic frames) are required together with radiotherapy devices capable of generating conformed beams (lineal accelerator, gammaknife, cyberknife, tomotherapy, cyclotrons). Modern stereotactic radiotherapy employs intra-tumoural radio-opaque frames or CAT image systems included in the irradiation device, which make possible a precise localisation of mobile lesions in each treatment session. Besides, technological advances make it possible to coordinate the lesion's movements in breathing with the radiotherapy unit (gating and tracking) for maximum tightening of margins and excluding a greater volume of healthy tissue. Radiosurgery is mainly indicated in benign or malign cerebral lesions less than 3-4 centimetres (arteriovenous malformations, neurinomas, meningiomas, cerebral metastases) and stereotactic radiotherapy is basically administered in tumours of extracraneal localisation that require high conforming and precision, such as inoperable early lung cancer and hepatic metastasis.

  12. Proportional counter radiation camera

    Science.gov (United States)

    Borkowski, C.J.; Kopp, M.K.

    1974-01-15

    A gas-filled proportional counter camera that images photon emitting sources is described. A two-dimensional, positionsensitive proportional multiwire counter is provided as the detector. The counter consists of a high- voltage anode screen sandwiched between orthogonally disposed planar arrays of multiple parallel strung, resistively coupled cathode wires. Two terminals from each of the cathode arrays are connected to separate timing circuitry to obtain separate X and Y coordinate signal values from pulse shape measurements to define the position of an event within the counter arrays which may be recorded by various means for data display. The counter is further provided with a linear drift field which effectively enlarges the active gas volume of the counter and constrains the recoil electrons produced from ionizing radiation entering the counter to drift perpendicularly toward the planar detection arrays. A collimator is interposed between a subject to be imaged and the counter to transmit only the radiation from the subject which has a perpendicular trajectory with respect to the planar cathode arrays of the detector. (Official Gazette)

  13. Imaging with terahertz radiation

    Science.gov (United States)

    Chan, Wai Lam; Deibel, Jason; Mittleman, Daniel M.

    2007-08-01

    Within the last several years, the field of terahertz science and technology has changed dramatically. Many new advances in the technology for generation, manipulation, and detection of terahertz radiation have revolutionized the field. Much of this interest has been inspired by the promise of valuable new applications for terahertz imaging and sensing. Among a long list of proposed uses, one finds compelling needs such as security screening and quality control, as well as whimsical notions such as counting the almonds in a bar of chocolate. This list has grown in parallel with the development of new technologies and new paradigms for imaging and sensing. Many of these proposed applications exploit the unique capabilities of terahertz radiation to penetrate common packaging materials and provide spectroscopic information about the materials within. Several of the techniques used for terahertz imaging have been borrowed from other, more well established fields such as x-ray computed tomography and synthetic aperture radar. Others have been developed exclusively for the terahertz field, and have no analogies in other portions of the spectrum. This review provides a comprehensive description of the various techniques which have been employed for terahertz image formation, as well as discussing numerous examples which illustrate the many exciting potential uses for these emerging technologies.

  14. The dosimetry of ionizing radiation

    CERN Document Server

    1990-01-01

    A continuation of the treatise The Dosimetry of Ionizing Radiation, Volume III builds upon the foundations of Volumes I and II and the tradition of the preceeding treatise Radiation Dosimetry. Volume III contains three comprehensive chapters on the applications of radiation dosimetry in particular research and medical settings, a chapter on unique and useful detectors, and two chapters on Monte Carlo techniques and their applications.

  15. Occupation: nurse; occupational hazard: radiation

    Energy Technology Data Exchange (ETDEWEB)

    Nickson, K.

    1984-03-01

    The work of the occupational health nurses at the Pickering Generating Station is described. A staff of two nurses teach first aid and safety, practice an emergency plan, and monitor personnel for minimum health standards for radiation workers. Special attention is paid to problems which might be aggravated by radiation, such as skin complaints, respiratory diseases, emotional stability, or phobias regarding heights, plastic suits, or radiation itself. Procedures used in treating contaminated personnel are outlined.

  16. DETERMINATION OF RADIATOR COOLING SURFACE

    Directory of Open Access Journals (Sweden)

    A. I. Yakubovich

    2009-01-01

    Full Text Available The paper proposes a methodology for calculation of a radiator cooling surface with due account of heat transfer non-uniformity on depth of its core. Calculation of radiator cooling surfaces of «Belarus-1221» and «Belarus-3022» tractors has been carried out in the paper. The paper also advances standard size series of radiators for powerful «Belarus» tractor type.

  17. On Divergence in Radiation Fields

    CERN Document Server

    Fricke, Joerg

    2016-01-01

    Three thought experiments demonstrate that under certain circumstances radiation fields have to be attenuated or amplified multiplicatively in order not to violate the conservation of energy. Modulation of radiation by means other than superposition is theoretically made possible by plugging additional terms into the source slots of the Maxwell equations. Modulated radiation would enable the well focused stimulation of neurons for diagnostic and therapeutic purposes.

  18. Radiation monitoring around accelerator facilities

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Shinichi [High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan)

    2000-07-01

    The present status of a network of radiation monitors (NORM) working at KEK is described in detail. NORM consists of there parts; stand-alone radiation monitors (SARM), local-monitoring stations (STATION) and a central data-handling system (CENTER). NORM has developed to a large-scaled monitoring system in which more than 250 SARMs are under operation for monitoring the radiation fields and radioactivities around accelerators in KEK. (author)

  19. Space Flight Ionizing Radiation Environments

    Science.gov (United States)

    Koontz, Steve

    2017-01-01

    The space-flight ionizing radiation (IR) environment is dominated by very high-kinetic energy-charged particles with relatively smaller contributions from X-rays and gamma rays. The Earth's surface IR environment is not dominated by the natural radioisotope decay processes. Dr. Steven Koontz's lecture will provide a solid foundation in the basic engineering physics of space radiation environments, beginning with the space radiation environment on the International Space Station and moving outward through the Van Allen belts to cislunar space. The benefits and limitations of radiation shielding materials will also be summarized.

  20. Radiation Therapy of Pituitary Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Park, Moon Baik; Hong, Seong Eong [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

    1989-12-15

    Radiation treatment results were analyzed in a retrospective analysis of 47 patients with pituitary adenoma treated with radiation alone or combined with surgery from 1974 through 1987 at the Department of Therapeutic Radiology of Kyung Hee University. The 5-year overall survival rates for all patients was 80.4%. Radiation therapy was effective for improving visual symptoms and headache, but could not normalize amenorrhea and galactorrhoea. There was no difference of survival rate between radiation alone and combination with surgery. Prognostic factors such as age, sex, disease type, visual field, headache and surgical treatment were statistically no significant in survival rates of these patients.

  1. Ethical problems in radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Shrader-Frechette, K.; Persson, Lars

    2001-05-01

    In this report the authors survey existing international radiation-protection recommendations and standards of the ICRP, the IAEA, and the ILO. After outlining previous work on the ethics of radiation protection, professional ethics, and the ethics of human radiation experiments, the authors review ethical thinking on seven key issues related to radiation protection and ethics. They formulate each of these seven issues in terms of alternative ethical stances: (1) equity versus efficiency, (2) health versus economics, (3) individual rights versus societal benefits, (4) due process versus necessary sacrifice, (5) uniform versus double standards, (6) stake holder consent versus management decisions, and (7) environmental stewardship versus anthropocentric standards.

  2. Radiation reaction in fusion plasmas.

    Science.gov (United States)

    Hazeltine, R D; Mahajan, S M

    2004-10-01

    The effects of a radiation reaction on thermal electrons in a magnetically confined plasma, with parameters typical of planned burning plasma experiments, are studied. A fully relativistic kinetic equation that includes the radiation reaction is derived. The associated rate of phase-space contraction is computed and the relative importance of the radiation reaction in phase space is estimated. A consideration of the moments of the radiation reaction force show that its effects are typically small in reactor-grade confined plasmas, but not necessarily insignificant.

  3. Cardiac imaging: does radiation matter?

    Science.gov (United States)

    Einstein, Andrew J.; Knuuti, Juhani

    2012-01-01

    The use of ionizing radiation in cardiovascular imaging has generated considerable discussion. Radiation should not be considered in isolation, but rather in the context of a careful examination of the benefits, risks, and costs of cardiovascular imaging. Such consideration requires an understanding of some fundamental aspects of the biology, physics, epidemiology, and terminology germane to radiation, as well as principles of radiological protection. This paper offers a concise, contemporary perspective on these areas by addressing pertinent questions relating to radiation and its application to cardiac imaging. PMID:21828062

  4. Radiation Shielding for Space Flight

    Science.gov (United States)

    Blattnig, Steve R.; Norbury, John W.; Norman, Ryan B.

    2003-01-01

    A safe and efficient exploration of space requires an understanding of space radiations so that human life and sensitive equipment can be protected. On the way to these sensitive sites, the radiation is modified in both quality and quantity. Many of these modifications are thought to be due to the production of pions and muons in the interactions between the radiation and intervening matter. A method to predict the effects of the presence of these particles on the transport of radiation through materials is presented.

  5. Diffusion effects in undulator radiation

    Directory of Open Access Journals (Sweden)

    Ilya Agapov

    2014-11-01

    Full Text Available Quantum diffusion effects in undulator radiation in semiclassical approximation are considered. Short-term effects on the electron beam motion are discussed and it is shown that approaches based on diffusion approximation with drift-diffusion coefficients derived from undulator or bending magnet radiation spectrum, and on Poisson statistics with radiation spectrum defined by the local beding field, all lead to similar results in terms of electron energy spread for cases of practical interest. An analytical estimate of the influence of quantum diffusion on the undulator radiation spectrum is derived.

  6. Nanocomposite for Radiation Shielding Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA's Advanced Extravehicular Activity (EVA) program requires the need for materials that can protect astronauts and spacecrafts from ionizing radiations such as...

  7. Doses from Medical Radiation Sources

    Science.gov (United States)

    ... Memoriam Sections All Sections (listing) Accelerator AIRRS Decommissioning Environmental/Radon Homeland Security Instrumentation Medical Health Physics Military Health Physics Nonionizing Radiation Power Reactor Affiliates ...

  8. Radiation protection in medical imaging and radiation oncology

    CERN Document Server

    Stoeva, Magdalena S

    2016-01-01

    Radiation Protection in Medical Imaging and Radiation Oncology focuses on the professional, operational, and regulatory aspects of radiation protection. Advances in radiation medicine have resulted in new modalities and procedures, some of which have significant potential to cause serious harm. Examples include radiologic procedures that require very long fluoroscopy times, radiolabeled monoclonal antibodies, and intravascular brachytherapy. This book summarizes evidence supporting changes in consensus recommendations, regulations, and health physics practices associated with these recent advances in radiology, nuclear medicine, and radiation oncology. It supports intelligent and practical methods for protection of personnel, the public, and patients. The book is based on current recommendations by the International Commission on Radiological Protection and is complemented by detailed practical sections and professional discussions by the world’s leading medical and health physics professionals. It also ...

  9. Radiation damping forces and radiation from charged particles

    Science.gov (United States)

    Klepikov, N. P.

    1985-06-01

    In the present evaluation of reported results on the radiation reaction force to which a charged particle is subject, the expression obtained for this force by Lorentz (1909), Abraham (1904), and Dirac (1938) is noted to be in physically reasonable agreement with the radiation of energy, momentum and angular momentum; it has, moreover, been successfully used in investigations of the motion of particles in a field. A theory is presented for the losses of energy, momentum, and angular momentum by a system of charged particles as they move together, taking the external field, the radiation damping forces, and the retarded Lienard-Wiechert forces into account. Formulas are given for the spectral and angular distribution of the radiation from a system of particles, and a system of equations is constructed for finding the angular momenta of EM waves radiated by particles of the system.

  10. Radiation practices. Annual report 2011

    Energy Technology Data Exchange (ETDEWEB)

    Rantanen, E. (ed.)

    2012-09-15

    1791 safety licences for the use of radiation were current at the end of 2011. 1702 responsible parties were engaged in notifiable licence-exempt dental X-ray activities. Use of radiation was controlled through regular inspections performed at places of use, test packages sent by post to dental X-ray facilities and maintenance of the Dose Register. Radiation safety guides were also published and research was conducted in support of regulatory control. The Radiation and Nuclear Safety Authority (STUK) conducted 575 inspections of licensed practices in 2011. 633 repair orders and recommendations were issued in the course of inspections. A total of nearly 11 700 workers were subject to individual monitoring in 2011 and about 143 000 dose entries were made in the Dose Register maintained by STUK. Regulatory control of natural radiation focused on radon at workplaces and exposure of aircrews to cosmic radiation. 166 workplaces including a total of 288 work areas were subject to radon monitoring during 2011. Just over 3600 cockpit and cabin crew members were monitored for exposure to cosmic radiation. STUK was involved in four ionizing radiation research projects, and also took part in an international expert group evaluation of STUK research activities. New alpha and beta sources were procured for metrological activities and a Co-60 irradiation device procured in 2010 was installed and taken into use. Calibration and testing services continued as in previous years. Regulatory control of the use of non-ionizing radiation in 2011 focused particularly on mobile phones, sunbeds and lasers. Orders were issued to 5 responsible parties to discontinue the use of tattoo removal lasers. 7 sunbed facilities were inspected and 10 on-site laser display inspections were performed. Five mobile phone types were tested in market surveillance of wireless communication devices. Non-ionizing radiation research activities were also subjected to the evaluation of STUK research activities

  11. Dark Radiative Inverse Seesaw

    CERN Document Server

    Ahriche, Amine; Nasri, Salah

    2016-01-01

    We present a minimal model that simultaneously accounts for neutrino masses and the origin of dark matter (DM) and where the electroweak phase transition is strong enough to allow for electroweak baryogenesis. The Standard Model is enlarged with a Majorana fermion, three generations of chiral fermion pairs, and a single complex scalar that plays a central role in DM production and phenomenology, neutrino masses, and the strength of the phase transition. All the new fields are singlets under the SM gauge group. Neutrino masses are generated via a new variant of radiative inverse seesaw where the required small mass term is generated via loops involving DM and no large hierarchy is assumed among the mass scales. The model offers all the advantage of low-scale neutrino mass models as well as a viable dark matter candidate that is testable with direct detection experiments.

  12. Antiangiogenic and Radiation Therapy

    Science.gov (United States)

    Ren, Ying; Fleischmann, Dominik; Foygel, Kira; Molvin, Lior; Lutz, Amelie M.; Koong, Albert C.; Jeffrey, R. Brooke; Tian, Lu; Willmann, Jürgen K.

    2015-01-01

    Objectives To assess early treatment effects on computed tomography (CT) perfusion parameters after antiangiogenic and radiation therapy in subcutaneously implanted, human colon cancer xenografts in mice and to correlate in vivo CT perfusion parameters with ex vivo assays of tumor vascularity and hypoxia. Materials and Methods Dynamic contrast-enhanced CT (perfusion CT, 129 mAs, 80 kV, 12 slices × 2.4 mm; 150 μL iodinated contrast agent injected at a rate of 1 mL/min intravenously) was performed in 100 subcutaneous human colon cancer xenografts on baseline day 0. Mice in group 1 (n = 32) received a single dose of the antiangiogenic agent bevacizumab (10 mg/kg body weight), mice in group 2 (n = 32) underwent a single radiation treatment (12 Gy), and mice in group 3 (n = 32) remained untreated. On days 1, 3, 5, and 7 after treatment, 8 mice from each group underwent a second CT perfusion scan, respectively, after which tumors were excised for ex vivo analysis. Four mice were killed after baseline scanning on day 0 for ex vivo analysis. Blood flow (BF), blood volume (BV), and flow extraction product were calculated using the left ventricle as an arterial input function. Correlation of in vivo CT perfusion parameters with ex vivo microvessel density and extent of tumor hypoxia were assessed by immunofluorescence. Reproducibility of CT perfusion parameter measurements was calculated in an additional 8 tumor-bearing mice scanned twice within 5 hours with the same CT perfusion imaging protocol. Results The intraclass correlation coefficients for BF, BV, and flow extraction product from repeated CT perfusion scans were 0.93 (95% confidence interval: 0.78, 0.97), 0.88 (0.66, 0.95), and 0.88 (0.56, 0.95), respectively. Changes in perfusion parameters and tumor volumes over time were different between treatments. After bevacizumab treatment, all 3 perfusion parameters significantly decreased from day 1 (P ≤ 0.006) and remained significantly decreased until day 7 (P ≤ 0

  13. Radiative light dark matter

    Science.gov (United States)

    Dedes, A.; Karamitros, D.; Pilaftsis, A.

    2017-06-01

    We present a Peccei-Quinn (PQ)-symmetric two-Higgs doublet model that naturally predicts a fermionic singlet dark matter in the mass range 10 keV-1 GeV. The origin of the smallness of the mass of this light singlet fermion arises predominantly at the one-loop level, upon soft or spontaneous breakdown of the PQ symmetry via a complex scalar field in a fashion similar to the so-called Dine-Fischler-Sredniki-Zhitnitsky axion model. The mass generation of this fermionic radiative light dark matter (RLDM) requires the existence of two heavy vectorlike SU(2) isodoublets, which are not charged under the PQ symmetry. We show how the RLDM can be produced via the freeze-in mechanism, thus accounting for the missing matter in the Universe. Finally, we briefly discuss possible theoretical and phenomenological implications of the RLDM model for the strong C P problem and the CERN Large Hadron Collider (LHC).

  14. Thermodynamics of radiation modes

    Energy Technology Data Exchange (ETDEWEB)

    Pina, Eduardo; De la Selva, Sara Maria Teresa [Departamento de Fisica, Universidad Autonoma Metropolitana - Iztapalapa, PO Box 55 534, Mexico, D F, 09340 (Mexico)], E-mail: pge@xanum.uam.mx, E-mail: tere@xanum.uam.mx

    2010-03-15

    We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the frequencies. One equation relating frequency and volume is used to define the thermodynamics of one mode, and to explain the mystery of the frequency-dependent quantities having a similar behaviour to the non-frequency-dependent quantities for some thermodynamic equations and different behaviour for others. Besides, this frequency-volume relation is used to count the number of modes in a band of frequency.

  15. Radiation induced femoral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Aranda, B.; Esnault, S.; Brunet, P. (Hopital de la Salpetriere, Paris (France))

    1982-01-01

    We report four cases of femoral palsy due to compressive fibrosis, after pelvic radiation therapy. Three patients had Hodgkin's disease, and one testicular seminoma. Prominent clinical features include major groin induration and underlying swelling. Unlike what is usually seen in tumoral relapse, little or no pain is associated with these neuropathies. The femoral post-radic palsy develops earlier and faster than brachial plexus palsy of same aetiology. In one case, progressive aggravation led to surgical neurolysis which resulted in dramatic and long lasting improvement. The principal preventive and therapeutic management methods are discussed: since compressive fibrosis is related to the use of isolated and massive electron beam therapy, various associations of cobalt and electron beam therapy are designed to best prevent the side effects of each of these methods. The early treatment of developing fibrosis by D. penicillamine is discussed.

  16. Thermostatic Radiator Valve Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, J. [Advanced Residential Integrated Energy Solutions Collaborative (ARIES), New York, NY (United States); Ansanelli, E. [Advanced Residential Integrated Energy Solutions Collaborative (ARIES), New York, NY (United States)

    2015-01-01

    A large stock of multifamily buildings in the Northeast and Midwest are heated by steam distribution systems. Losses from these systems are typically high and a significant number of apartments are overheated much of the time. Thermostatically controlled radiator valves (TRVs) are one potential strategy to combat this problem, but have not been widely accepted by the residential retrofit market. In this project, the ARIES team sought to better understand the current usage of TRVs by key market players in steam and hot water heating and to conduct limited experiments on the effectiveness of new and old TRVs as a means of controlling space temperatures and reducing heating fuel consumption. The project included a survey of industry professionals, a field experiment comparing old and new TRVs, and cost-benefit modeling analysis using BEopt™ (Building Energy Optimization software).

  17. Radiation imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Bobbitt, III, John T.; Immel, David M.; Folsom, Matthew D.; Plummer, Jean R.; Serrato, Michael G.

    2016-06-28

    A radiation imaging system includes a casing and a camera disposed inside the casing. A first field of view through the casing exposes the camera to light from outside of the casing. An image plate is disposed inside the casing, and a second field of view through the casing to the image plate exposes the image plate to high-energy particles produced by a radioisotope outside of the casing. An optical reflector that is substantially transparent to the high-energy particles produced by the radioisotope is disposed with respect to the camera and the image plate to reflect light to the camera and to allow the high-energy particles produced by the radioisotope to pass through the optical reflector to the image plate.

  18. Radiation imaging system

    Energy Technology Data Exchange (ETDEWEB)

    Immel, David M.; Bobbit, III, John T.; Plummer, Jean R.; Folsom, Matthew D.; Serrato, Michael G.

    2016-03-22

    A radiation imaging system includes a casing and a camera disposed inside the casing. A first field of view through the casing exposes the camera to light from outside of the casing. An image plate is disposed inside the casing, and a second field of view through the casing to the image plate exposes the image plate to high-energy particles produced by a radioisotope outside of the casing. An optical reflector that is substantially transparent to the high-energy particles produced by the radioisotope is disposed with respect to the camera and the image plate to reflect light to the camera and to allow the high-energy particles produced by the radioisotope to pass through the optical reflector to the image plate.

  19. The radiation of ULTEM

    Energy Technology Data Exchange (ETDEWEB)

    Sheila, D.; Hill, D.J.; Whitaker, A.K. [The University of Queensland, Brisbane, QLD (Australia). Department of Chemistry, Polymer Material and Radiation Group

    1998-12-31

    Polyimide polymers and membranes have interesting mechanical, thermal and electrical properties, and useful for industrial applications. They are also known for their exceptional thermo-oxidative and chemical resistance. High performance linear aromatic polymers with skeletons composed primarily of aromatic units are expected to be the materials used in high energy radiation fields, such as space and fusion reactor environments. In this study the ESR technique was employed to study the radiation resistivity of ULTEM. Gamma irradiations were carried out at 77 K and the ambient temperature. The neutral and anionic free radicals produced at 52 Mrad, and 77 K were further thermally annealed to just above glass transition temperature. The annealing resulted in two decay regions, namely 130-230 K and above 250 K, corresponding to the decay of anion radicals and neutral radicals respectively. The sample was further irradiated for 20 Mrads at 77 K. Photobleaching with visible light at 610 nm and 510 nm were carried out to detrap the anionic radicals. It was observed that up to 71% of the radicals were detrapped by photobleaching. Further annealing up to 490 K, following the photobleaching, showed complete decay of the radicals. {sup 1}H and {sup 13}C NMR of the polymers irradiated at 100, 250 and 500 Mrad clearly showed the evidence of cross linking at 250 Mrad. New peaks were identified for {sup 1}H NMR at {delta} 1.60 a 7.04. GPC results of the irradiated polymer at 52, 100, and 250 Mrad showed increase in molecular weight after initial decline

  20. Cherenkov radiation in moving medium

    OpenAIRE

    2010-01-01

    Cherenkov radiation in uniformly moving homogenous isotropic medium without dispersion is studied. Formula for the spectrum of Cherenkov radiation of fermion was derived for the case when the speed of the medium is less than the speed of light in this medium at rest. The properties of Cherenkov spectrum are investigated.

  1. Radiation carcinogenesis: radioprotectors and photosensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Fry, R.J.M.

    1982-01-01

    This paper outlines 1) some of the salient features of radiation carcinogenesis that are pertinent to the questions of how the carcinogenic effects might be influenced, 2) the effects of radioprotectors on ionizing radiation-induced cancer, and 3) the effect of photosensitizers on UVR-induced skin cancer.

  2. Chemical Protection Against Ionizing Radiation.

    Science.gov (United States)

    1984-08-01

    experimentally obtained. SPONSOR: Div of Cancer Treatment, NIH /A TOPICS: 2D PI/ORG: Moss, Alfred J; Veterans Administration Ned Ctr, Little Rock AR TITLE...Robert C; Dartmouth- Hitchcock Ned Ctr, Hanover NH TITLE: Radiation-chemical induction of mutagenesis. SUMMARY: Effects of sensitizers on radiation

  3. Air and radiation monitoring stations

    CERN Multimedia

    AUTHOR|(SzGeCERN)582709

    2015-01-01

    CERN has around 100 monitoring stations on and around its sites. New radiation measuring stations, capable of detecting even lower levels of radiation, were installed in 2014. Two members of HE-SEE group (Safety Engineering and Environment group) in front of one of the new monitoring stations.

  4. Radiation curing in the eighties

    Energy Technology Data Exchange (ETDEWEB)

    Vrancken, A. (UCB, Drogenbos (Belgium). Chemical Specialities Div.)

    1984-05-01

    The subject is discussed under the headings: introduction; what is radiation curing; history; radiation curable resins (with properties of products); ultraviolet and electron beam curing; photoinitiation and the ultraviolet light curing process; electron beam curing (initiation; electron beam accelerators); end uses (graphic arts; wood finishing; paper upgrading; adhesives; metal finishing; electronic chemical; floor coatings).

  5. Synchrotron radiation from massless charge

    Directory of Open Access Journals (Sweden)

    D.V. Gal'tsov

    2015-07-01

    Full Text Available Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some authors suggest that strictly massless charge does not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for ab initio massless particle of zero spin. Provided E2≫eH, the maximum in the spectrum is shown to be at ħω=E/3, and the average photon energy is 4E/9. The normalized spectrum is universal, depending neither on E nor on H. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Classical theory is reliable only as providing the low-frequency part of the true quantum radiation spectrum.

  6. Biological Research for Radiation Protection

    Energy Technology Data Exchange (ETDEWEB)

    Kim, In Gyu; Kim, Kug Chan; Jung, Il Lae; Choi, Yong Ho; Kim, Jin Sik; Moon, Myung Sook; Byun, Hee Sun; Phyo, Ki Heon; Kim, Sung Keun

    2005-04-15

    The work scope of 'Biological Research for the Radiation Protection' had contained the research about ornithine decarboxylase and its controlling proteins, thioredoxin, peroxiredoxin, S-adenosymethionine decarboxylase, and glutamate decarboxylase 67KD effect on the cell death triggered ionizing radiation and H{sub 2}O{sub 2}(toxic agents). In this study, to elucidate the role of these proteins in the ionizing radiation (or H{sub 2}O{sub 2})-induced apoptotic cell death, we utilized sensesed (or antisensed) cells, which overexpress (or down-regulate) RNAs associated with these proteins biosynthesis, and investigated the effects of these genes on the cytotoxicity caused by ionizing radiation and H{sub 2}O{sub 2}(or paraquat). We also investigated whether genisteine(or thiamine) may enhance the cytotoxic efficacy of tumor cells caused by ionizing radiation (may enhance the preventing effect radiation or paraquat-induced damage) because such compounds are able to potentiate the cell-killing or cell protecting effects. Based on the above result, we suggest that the express regulation of theses genes have potentially importance for sensitizing the efficiency of radiation therapy of cancer or for protecting the radiation-induced damage of normal cells.

  7. Cancer risks after radiation exposures

    Energy Technology Data Exchange (ETDEWEB)

    Voelz, G.L.

    1980-01-01

    A general overview of the effects of ionizing radiation on cancer induction is presented. The relationship between the degree of risk and absorbed dose is examined. Mortality from radiation-induced cancer in the US is estimated and percentages attributable to various sources are given. (ACR)

  8. Teaching about Natural Background Radiation

    Science.gov (United States)

    Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

    2013-01-01

    Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…

  9. Radiation Safety Aspects of Nanotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Hoover, Mark [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Myers, David; Cash, Leigh Jackson [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Guilmette, Raymond [Ray Guilmette & Associates, LLC, Perry, ME (United States); Kreyling, Wolfgang [Helmholtz-Zentrum Munchen, (Germany); Oberdorster, Gunter [Univ. of Rochester, NY (United States); Smith, Rachel [Public Health England, Oxfordshire (United Kingdom). Centre for Radiation, Chemical and Environmental Hazards

    2017-03-27

    This Report is intended primarily for operational health physicists, radiation safety officers, and internal dosimetrists who are responsible for establishing and implementing radiation safety programs involving radioactive nanomaterials. It should also provide useful information for workers, managers and regulators who are either working directly with or have other responsibilities related to work with radioactive nanomaterials.

  10. Radiation camera motion correction system

    Science.gov (United States)

    Hoffer, P.B.

    1973-12-18

    The device determines the ratio of the intensity of radiation received by a radiation camera from two separate portions of the object. A correction signal is developed to maintain this ratio at a substantially constant value and this correction signal is combined with the camera signal to correct for object motion. (Official Gazette)

  11. Workshops on radiation imaging detectors

    Energy Technology Data Exchange (ETDEWEB)

    Sochinskii, N.V.; Sun, G.C.; Kostamo, P.; Silenas, A.; Saynatjoki, A.; Grant, J.; Owens, A.; Kozorezov, A.G.; Noschis, E.; Van Eijk, C.; Nagarkar, V.; Sekiya, H.; Pribat, D.; Campbell, M.; Lundgren, J.; Arques, M.; Gabrielli, A.; Padmore, H.; Maiorino, M.; Volpert, M.; Lebrun, F.; Van der Putten, S.; Pickford, A.; Barnsley, R.; Anton, M.E.G.; Mitschke, M.; Gros d' Aillon, E.; Frojdh, C.; Norlin, B.; Marchal, J.; Quattrocchi, M.; Stohr, U.; Bethke, K.; Bronnimann, C.H.; Pouvesle, J.M.; Hoheisel, M.; Clemens, J.C.; Gallin-Martel, M.L.; Bergamaschi, A.; Redondo-Fernandez, I.; Gal, O.; Kwiatowski, K.; Montesi, M.C.; Smith, K

    2005-07-01

    This document gathers the transparencies that were presented at the international workshop on radiation imaging detectors. 9 sessions were organized: 1) materials for detectors and detector structure, 2) front end electronics, 3) interconnected technologies, 4) space, fusion applications, 5) the physics of detection, 6) industrial applications, 7) synchrotron radiation, 8) X-ray sources, and 9) medical and other applications.

  12. Nanocomposites for electromagnetic radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Petrunin, V. F., E-mail: VFPetrunin@mephi.ru [National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) (Russian Federation)

    2016-12-15

    Specific features that characterize nanoparticles and which are due to their small size and allow one to enhance the interaction between the electromagnetic radiation and nanostructured materials and to develop the effective protection of man and equipment against harmful uncontrolled radiation are reported. Examples of the development of nanocomposite radar absorbing materials that can be used for protection of man and equipment are presented.

  13. The program RADLST (Radiation Listing)

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, T.W.

    1988-02-29

    The program RADLST (Radiation Listing) is designed to calculate the nuclear and atomic radiations associated with the radioactive decay of nuclei. It uses as its primary input nuclear decay data in the Evaluated Nuclear Structure Data File (ENSDF) format. The code is written in FORTRAN 77 and, with a few exceptions, is consistent with the ANSI standard. 65 refs.

  14. Commentary on inhaled {sup 239}PuO{sub 2} in dogs - a prophylaxis against lung cancer?

    Energy Technology Data Exchange (ETDEWEB)

    Cuttler, J.M. [Cuttler and Assoc., Vaughan, Ontario (Canada); Feinendegen, L. [Brookhaven National Laboratories, Upton, New York (United States)

    2015-06-15

    Several studies on the effect of inhaled plutonium-dioxide particulates and the incidence of lung tumors in dogs reveal beneficial effects when the cumulative alpha-radiation dose is low. There is a threshold at an exposure level of about 100 cGy for excess tumor incidence and reduced lifespan. The observations conform to the expectations of the radiation hormesis dose-response model and contradict the predictions of the Linear No-Threshold (LNT) hypothesis. These studies suggest investigating the possibility of employing low-dose alpha-radiation, such as from {sup 239}PuO {sub 2} inhalation, as a prophylaxis against lung cancer. (author)

  15. Hawking Radiation in Dispersive Media

    CERN Document Server

    Robertson, Scott James

    2011-01-01

    Hawking radiation, despite its presence in theoretical physics for over thirty years, remains elusive and undetected. It also suffers, in its original context of gravitational black holes, from conceptual difficulties. Of particular note is the trans-Planckian problem, which is concerned with the apparent origin of the radiation in absurdly high frequencies. In order to gain better theoretical understanding and, it is hoped, experimental verification of Hawking radiation, much study is being devoted to systems which model the spacetime geometry of black holes, and which, by analogy, are also thought to emit Hawking radiation. These analogue systems typically exhibit dispersion, which regularizes the wave behaviour at the horizon but does not lend itself well to analytic treatment, thus rendering Hawking's prediction less secure. A general analytic method for dealing with Hawking radiation in dispersive systems has proved difficult to find. This thesis presents new numerical and analytic results for Hawking em...

  16. Measurement and detection of radiation

    CERN Document Server

    Tsoulfanidis, Nicholas

    2011-01-01

    This is an update of the standard textbook for the field of radiation measurement. It includes illustrative examples and new problems. The research and applications of nuclear instrumentation have grown substantially since publication of the previous editions. With the miniaturization of equipment, increased speed of electronic components, and more sophisticated software, radiation detection systems are now more productively used in many disciplines, including nuclear nonproliferation, homeland security, and nuclear medicine. Continuing in the tradition of its bestselling predecessors, "Measurement and Detection of Radiation, Third Edition" illustrates the fundamentals of nuclear interactions and radiation detection with a multitude of examples and problems. It offers a clearly written, accessible introduction to nuclear instrumentation concepts. The following are new to the third edition: a new chapter on the latest applications of radiation detection, covering nuclear medicine, dosimetry, health physics, no...

  17. Radiation physics for medical physicists

    CERN Document Server

    Podgorsak, Ervin B

    2006-01-01

    This book summarizes the radiation physics knowledge that professionals working in medical physics need to master for efficient and safe dealings with ionizing radiation. It contains eight chapters, each chapter covering a specific group of subjects related to radiation physics and is intended as a textbook for a course in radiation physics in medical-physics graduate programs. However, the book may also be of interest to the large number of professionals, not only medical physicists, who in their daily occupations deal with various aspects of medical physics and find a need to improve their understanding of radiation physics. The main target audience for this book is graduate students studying for M.Sc. and Ph.D. degrees in medical physics, who have to possess the necessary physics and mathematics background knowledge to be able to follow and master the complete textbook. Medical residents, technology students and biomedical engineering students may find certain sections too challenging or esoteric, yet they...

  18. Radiation feedback in dusty clouds

    Science.gov (United States)

    Ishiki, Shohei; Okamoto, Takashi

    2017-03-01

    We have investigated the impact of photoionization and radiation pressure on a dusty star-forming cloud using one-dimensional radiation hydrodynamic simulations, which include absorption and re-emission of photons by dust. We find that, in a cloud of mass 105 M⊙ and radius 17 pc, the effect of radiation pressure is negligible when star formation efficiency is 2 per cent. The importance of radiation pressure increases with increasing star formation efficiency or an increasing dust-to-gas mass ratio. The net effect of radiation feedback, however, becomes smaller with the increasing dust-to-gas mass ratio, since the absorption of ultraviolet photons by dust grains suppresses photoionization and hence photoheating.

  19. Status of radiation processing dosimetry

    DEFF Research Database (Denmark)

    Miller, A.

    1993-01-01

    Several milestones have marked the field of radiation processing dosimetry since IMRP 7. Among them are the IAEA symposium on High Dose Dosimetry for Radiation Processing and the international Workshops on Dosimetry for Radiation Processing organized by the ASTM. Several standards have been...... or are being published by the ASTM in this field, both on dosimetry procedures and on the proper use of specific dosimeter systems. Several individuals are involved in this international cooperation which contribute significantly to the broader understanding of the role of dosimetry in radiation processing....... The importance of dosimetry is emphasized in the standards on radiation sterilization which are currently drafted by the European standards organization CEN and by the international standards organization ISO. In both standards, dosimetry plays key roles in characterization of the facility, in qualification...

  20. Atomic spectroscopy and radiative processes

    CERN Document Server

    Landi Degl'Innocenti, Egidio

    2014-01-01

    This book describes the basic physical principles of atomic spectroscopy and the absorption and emission of radiation in astrophysical and laboratory plasmas. It summarizes the basics of electromagnetism and thermodynamics and then describes in detail the theory of atomic spectra for complex atoms, with emphasis on astrophysical applications. Both equilibrium and non-equilibrium phenomena in plasmas are considered. The interaction between radiation and matter is described, together with various types of radiation (e.g., cyclotron, synchrotron, bremsstrahlung, Compton). The basic theory of polarization is explained, as is the theory of radiative transfer for astrophysical applications. Atomic Spectroscopy and Radiative Processes bridges the gap between basic books on atomic spectroscopy and the very specialized publications for the advanced researcher: it will provide under- and postgraduates with a clear in-depth description of theoretical aspects, supported by practical examples of applications.

  1. Radiation Hardening of Silicon Detectors

    CERN Multimedia

    Leroy, C; Glaser, M

    2002-01-01

    %RD48 %title\\\\ \\\\Silicon detectors will be widely used in experiments at the CERN Large Hadron Collider where high radiation levels will cause significant bulk damage. In addition to increased leakage current and charge collection losses worsening the signal to noise, the induced radiation damage changes the effective doping concentration and represents the limiting factor to long term operation of silicon detectors. The objectives are to develop radiation hard silicon detectors that can operate beyond the limits of the present devices and that ensure guaranteed operation for the whole lifetime of the LHC experimental programme. Radiation induced defect modelling and experimental results show that the silicon radiation hardness depends on the atomic impurities present in the initial monocrystalline material.\\\\ \\\\ Float zone (FZ) silicon materials with addition of oxygen, carbon, nitrogen, germanium and tin were produced as well as epitaxial silicon materials with epilayers up to 200 $\\mu$m thickness. Their im...

  2. Essentials of radiation heat transfer

    CERN Document Server

    Balaji

    2014-01-01

    Essentials of Radiation Heat Transfer is a textbook presenting the essential, fundamental information required to gain an understanding of radiation heat transfer and equips the reader with enough knowledge to be able to tackle more challenging problems. All concepts are reinforced by carefully chosen and fully worked examples, and exercise problems are provided at the end of every chapter. In a significant departure from other books on this subject, this book completely dispenses with the network method to solve problems of radiation heat transfer in surfaces. It instead presents the powerful radiosity-irradiation method and shows how this technique can be used to solve problems of radiation in enclosures made of one to any number of surfaces. The network method is not easily scalable. Secondly, the book introduces atmospheric radiation, which is now being considered as a potentially important area, in which engineers can contribute to the technology of remote sensing and atmospheric sciences in general, b...

  3. Bistability in radiative heat exchange

    Science.gov (United States)

    Rudakov, V. I.; Ovcharov, V. V.; Prigara, V. P.

    2008-08-01

    The possibility of a bistable regime in systems with radiative heat exchange is theoretically demonstrated for the first time. The transfer characteristics of a radiation-closed stationary system have been calculated, in which the radiator is a blackbody and the absorber is made of a material with the absorptivity sharply increasing in a certain temperature interval. The radiator and absorber are separated by a vacuum gap. The heat exchange between the system and the environment is controlled by varying the flow rate of a heat-transfer agent cooling the absorber. The output parameter of a bistable system is the absorber temperature, while the input parameter can be either the radiator temperature or the heat-transfer agent flow rate. Depending on the choice of the input parameter, the transfer characteristic of the system is either represented by a usual S-like curve or has an inverted shape.

  4. Radiation physics for nuclear medicine

    CERN Document Server

    Hoeschen, Christoph

    2011-01-01

    The field of nuclear medicine is expanding rapidly, with the development of exciting new diagnostic methods and treatments. This growth is closely associated with significant advances in radiation physics. In this book, acknowledged experts explain the basic principles of radiation physics in relation to nuclear medicine and examine important novel approaches in the field. The first section is devoted to what might be termed the "building blocks" of nuclear medicine, including the mechanisms of interaction between radiation and matter and Monte Carlo codes. In subsequent sections, radiation sources for medical applications, radiopharmaceutical development and production, and radiation detectors are discussed in detail. New frontiers are then explored, including improved algorithms for image reconstruction, biokinetic models, and voxel phantoms for internal dosimetry. Both trainees and experienced practitioners and researchers will find this book to be an invaluable source of up-to-date information.

  5. Applying radiation health effects data to radiation protection policies

    Energy Technology Data Exchange (ETDEWEB)

    Muckerheide, James [Center for Nuclear Technology and Society at WPI, Worcester Polytechnic Institute, Worcester, MA (United States)

    2000-05-01

    Data from the peer-reviewed scientific literature establish a sound basis to define a low-dose, low-dose-rate, dose-response. These data include human health dose-response studies; immunologically 'whole' animal studies; and cellular and molecular biological studies of complete biological systems for the relevant immunological and physiological responses. Initiatives are required to constructively apply these data to both radiation research and radiation protection policies. First, current low level radiation health effects research must apply existing data to define research projects to integrate and confirm existing dose-response data, with specific emphasis on the biological bases that exist in definitive and reproducible cellular and biological dose-response. Second, dose-response assessment must identify and incorporate all existing substantial and confirmed data, including natural radiation sources, to establish the bases for radiation protection policy for interventions to protect public health and safety. A preliminary assessment of these data is applied to: 1) Specify research that can be constructively applied to describe radiation health effects dose-response. 2) Apply health effects dose-response to radiation and radioactivity applications policies to maximize radiation health effects interventions for occupational applications, medical applications, and other radiation and radioactive materials applications controls to cost-effectively assure public health and safety. An assessment of the proposed revisions to ICRP radiation protection policies is provided that associates the basis for administrative limits with the previous proposal of the US NRC for a 'Below Regulatory Concern' (BRC) policy. This proposal ignores the context of the fact that very low levels of radiation exposure are far within the variations of natural radiation exposures, and therefore can have no gross net consequences. The equivalent failure of the BRC proposal

  6. Optimization and radiation protection culture

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, In Young; Shin, Hyeong Ki; Lee, Chan Mi [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2013-04-15

    Safety culture or radiation protection culture is based in common on the term, 'culture'. Culture is defined as the learned, shared set of symbols and patterns of basic assumptions, which is invented, discovered, or developed by a given group as it learns to cope with its problem of external adaptation and internal integration. Safety culture generally refers to the attitude and behaviors affecting safety performance. The concept of 'Safety Culture' was introduced after the Chernobyl accident in 1986. For the accident, nuclear society reached the conclusion that the cause was the wrong management attitude of the NPP, that is, deficient 'Safety Culture'. Recently, 'Radiation Protection Culture' was introduced as the core concept of nuclear safety culture. There have been many efforts to establish definition and develop assessment tool for radiation protection culture in international level such as ICRP and IRPA as well as NRC. In the same context with the safety culture, radiation protection culture is defined as 'the core values and behaviors resulting from a collective commitment by leaders and individual's to emphasize safety over competing goals to ensure protection of people and the environment.' It is worthwhile to recognize that regulatory enforcement in establishing healthy radiation protection culture of operators should be minimized because culture is not in the domain of regulatory enforcement. However, as 'ALARA', the most important concept in radiation protection, may be successfully achieved only in well established radiation protection culture, the least regulatory intervention would be needed in promoting and nurturing radiation protection culture in licensee. In addition, the concept of radiation protection culture should be addressed in plant operational policy to achieve the goals of ALARA. The pre-condition of the successful radiation protection culture is a healthy organizational

  7. Radiation treatment and radiation reactions in dermatology. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Panizzon, Renato G. [Univ. Hospital CHUV, Lausanne (Switzerland). Dept. of Dermatology; Seegenschmiedt, M. Heinrich (ed.) [Strahlenzentrum Hamburg (Germany)

    2015-03-01

    Explains the use of radiation treatment in the full range of skin cancers and precancerous lesions. Covers physical and radiobiological principles, dose definitions, radiation reactions, and risk assessments. Revised and updated edition that includes new chapters and numerous additional figures. In this book, leading experts in the dermatological and oncological field describe the use of radiation therapy for the treatment of the full range of dermatological malignancies - including basal cell carcinoma, squamous cell carcinoma, cutaneous lymphomas, Kaposi's sarcoma, melanoma, and Merkel cell tumor - as well as those precancerous lesions and non-malignant dermatological disorders which are amenable to radiation therapy. In each case the specific indications for the use of radiotherapy and its application are clearly explained with the aid of numerous high-quality illustrations. In addition, the book provides a concise introduction to physical and radiobiological principles, selection of radiation factors, dose definitions, radiation reactions, and risk assessments. The new edition has been thoroughly revised and updated to reflect advances in practical knowledge and clinical practice. It will be an invaluable source of information on the management of skin tumors and related non-malignant disorders for both dermatologists, oncologists and radiation oncologists.

  8. Studies about space radiation promote new fields in radiation biology.

    Science.gov (United States)

    Ohnishi, Takeo; Takahashi, Akihisa; Ohnishi, Ken

    2002-12-01

    Astronauts are constantly exposed to space radiation of various types of energy with a low dose-rate during long-term stays in space. Therefore, it is important to determine correctly the biological effects of space radiation on human health. Studies about biological the effects at a low dose and a low dose-rate include various aspects of microbeams, bystander effects, radioadaptive responses and hormesis which are important fields in radiation biology. In addition, space radiations contain high linear energy transfer (LET) particles. In particular, neutrons may cause reverse effectiveness at a low dose-rate in comparison to ionizing radiation. We are also interested in p53-centered signal transduction pathways involved in the cell cycle, DNA repair and apoptosis induced by space radiations. We must also study whether the relative biological effectiveness (RBE) of space radiation is affected by microgravity which is another typical component in space. To confirm this, we must prepare centrifuge systems in an International Space Station (ISS). In addition, we must prepare many types of equipment for space experiments in an ISS, because we cannot use conventional equipment from our laboratories. Furthermore, the research for space radiation might give us valuable information about the birth and evolution of life on the Earth. We can also realize the importance of preventing the ozone layer from depletion by the use of exposure equipment to sunlight in an ISS. For these reasons, we desire to educate space researchers of the next generation based on the consideration of the preservation of the Earth from research about space radiation.

  9. Radiation by moving charges

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2017-04-15

    It is generally accepted that in order to describe the dynamics of relativistic particles in the laboratory (lab) frame it is sufficient to take into account the relativistic dependence of the particle momenta on the velocity. This solution of the dynamics problem in the lab frame makes no reference to Lorentz transformations. For this reason they are not discussed in particle tracking calculations in accelerator and plasma physics. It is generally believed that the electrodynamics problem can be treated within the same ''single inertial frame'' description without reference to Lorentz transformations. In particular, in order to evaluate radiation fields arising from charged particles in motion we need to know their velocities and positions as a function of the lab frame time t. The relativistic motion of a particle in the lab frame is described by Newton's second law ''corrected'' for the relativistic dependence of momentum on velocity. It is assumed in all standard derivations that one can perform identification of the trajectories in the source part of the usual Maxwell's equations with the trajectories vector x(t) measured (or calculated by using the corrected Newton's second law) in the lab frame. This way of coupling fields and particles is considered since more than a century as the relativistically correct procedure.We argue that this procedure needs to be changed, and we demonstrate the following, completely counterintuitive statement: the results of conventional theory of radiation by relativistically moving charges are not consistent with the principle of relativity. In order to find the trajectory of a particle in the lab frame consistent with the usual Maxwell's equations, one needs to solve the dynamic equation inmanifestly covariant form by using the coordinate-independent proper time τ to parameterize the particle world-line in space-time. We show that there is a difference between &apos

  10. The risks of radiation

    Science.gov (United States)

    Miettenen, Jorma K.

    1988-01-01

    The risks of radioactivity are a really complicated matter, yet they are much better known than are the risks relating to thousands of chemical poisons that occur in our environment. The greatest mistakes are probably made in the definition of safety margins. Except for the bombs dropped in Japan and one other case in the Marshall Islands, there has always—luckily—been a wide safety margin between fallout radiation and doses dangerous to health; the margin has actually been about 1000-fold. The Chernobyl dose of 0.5 mGy/year that we received is only 1/1000 of the acute dose of 0.5 Gy which would cause a slight and nonpermanent change in the blood picture. There is no such safety margin with respect to many air pollutants. The safety standards for sulfuric or nitric oxides, ozone and so on, have been set only just below the level that already causes a health hazard, and these standards are exceeded once in a while. Otherwise, traffic would have to be forbidden and many industrial plants, especially power stations using coal, would have to stop working whenever a low-temperature inversion occurred. Environmental radioactivity does not represent a likely health risk in Finland unless a nuclear war breaks out. Air pollutants, on the contrary, are a real and almost daily health risk that should be carefully considered when decisions about our energy production are being made. In spite of what happened at Chernobyl, global consumption of nuclear power will double by the year 2000, since there are about 140 nuclear power plants presently under construction. It is not likely that another catastrophe like Chernobyl will happen, yet nuclear plant accidents are of course possible, even if their likelihood is diminished by improving reactor safety and even if any eventual damage could be expected to be smaller. If a reactor is hooded by a containment structure, no significant release of radioactive materials should be possible even in case of an accident. However, we must

  11. Rapid Development of the Radiation Curing Sector

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Radiation curing is an advanced material surface treatment technology using ultraviolet (UV) radiation and electronic beams (EB). With the greater attention paid to environ mentel protection in recent years ,radiation curing has developed rapidly.

  12. Radiation feedback in dusty clouds

    CERN Document Server

    Ishiki, Shohei

    2016-01-01

    We have investigated the impact of photoionization and radiation pressure on a dusty star-forming cloud by one-dimensional radiation hydrodynamic simulations, which include absorption and re-emission of photons by dust. We find that even in a moderately dusty cloud with the infrared optical depth of 0.15, radiation pressure has strong impact on driving an outflow, while the effect of radiation pressure is negligible in a dustless cloud. The radiation pressure on dust creates an HII region whose density is much lower than that in a dustless cloud where an outflow is driven by thermal pressure of ionized gas. Due to the radiation pressure, a shocked shell expands with high velocity, > 100 km s^-1. Absorption of re-emitted photons by dust plays a significant role in driving an outflow when the infrared optical depth becomes unity and it increases the importance of radiation pressure. The column density of clouds decreases with very short timescale owing to the shell expansion. Because of the decline of the infra...

  13. Compton Sources of Electromagnetic Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey Krafft,Gerd Priebe

    2011-01-01

    When a relativistic electron beam interacts with a high-field laser beam, intense and highly collimated electromagnetic radiation will be generated through Compton scattering. Through relativistic upshifting and the relativistic Doppler effect, highly energetic polarized photons are radiated along the electron beam motion when the electrons interact with the laser light. For example, X-ray radiation can be obtained when optical lasers are scattered from electrons of tens-of-MeV beam energy. Because of the desirable properties of the radiation produced, many groups around the world have been designing, building, and utilizing Compton sources for a wide variety of purposes. In this review article, we discuss the generation and properties of the scattered radiation, the types of Compton source devices that have been constructed to date, and the prospects of radiation sources of this general type. Due to the possibilities of producing hard electromagnetic radiation in a device that is small compared to the alternative storage ring sources, it is foreseen that large numbers of such sources may be constructed in the future.

  14. Synchrotron radiation from massless charge

    CERN Document Server

    Gal'tsov, D V

    2015-01-01

    Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some general arguments suggest that strictly massless charge does not not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for {\\em ab initio} massless particle of zero spin. Provided $E^2\\gg eH$, the maximum in the spectrum is shown to be at $\\hbar \\omega=E/3$, and the average photon energy is $4E/9$. The normalized spectrum is universal, depending neither on $E$ nor on $H$. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Our results are consistent with the view (sup...

  15. DOE 2013 occupational radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-11-01

    The Office of Analysis within the U.S. Department of Energy (DOE) Office of Environment, Health, Safety and Security (EHSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2013 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past five-year period, the occupational radiation exposure information has been analyzed in terms of aggregate data, dose to individuals, and dose by site.

  16. Radiation-induced cardiovascular effects

    Science.gov (United States)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  17. IRPA initiative on radiation protection culture

    Science.gov (United States)

    Golnik, Natalia; Tulik, Piotr

    2011-01-01

    The concept of radiation protection culture, proposed by French Society for Radiation Protection (SFRP) and then launched by International Radiation Protection Association (IRPA) is presented. The paper is focused on the role of radiation culture in preventing unjustified fear associated with the use of radiation. Principles of RP culture and optimization of radiation protection, as well as the problems how RP culture can be learned and how to engage the stakeholders are considered.

  18. Topical Day on Biological Effects of Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Baatout, S.; Jacquet, P.

    1997-05-15

    The topical day has been focussed on the potential effects of ionizing radiation on human health. A general overview on molecular and biophysical aspects of radiation, its effects on cells and organisms, and the contribution of radiobiology to radiation protection and risk assessment is given. The genetic effects of radiation and its effects on the developing organism, the effects of radiation on the cell cycle and the mechanisms of radiation induced apoptosis were also discussed.

  19. Radiation Damage in Electronic Memory Devices

    OpenAIRE

    Irfan Fetahović; Milić Pejović; Miloš Vujisić

    2013-01-01

    This paper investigates the behavior of semiconductor memories exposed to radiation in order to establish their applicability in a radiation environment. The experimental procedure has been used to test radiation hardness of commercial semiconductor memories. Different types of memory chips have been exposed to indirect ionizing radiation by changing radiation dose intensity. The effect of direct ionizing radiation on semiconductor memory behavior has been analyzed by using Monte Carlo simula...

  20. Sacramento Regional Response Guide to Radiation Emergencies

    Science.gov (United States)

    2006-09-01

    heat, radio waves, and microwaves which are low level radiation energy which is referred to as non- ionizing radiation. High energy radiation is...Response Plan" (California Office of Emergency Services, Updated February 2001), 5. 41 • Department of Fish and Game-lead agency for petroleum spills...radiation-binding and radiation-ridding gels, foam products, films and emulsions . The goal of radiation decontamination is to be sensitive to the

  1. Obligatory Radiation Protection Course

    CERN Multimedia

    SC Unit

    2008-01-01

    Since February 2008, participation in the radiation protection course has been a prerequisite for obtaining a CERN personal dosimeter for all Staff Members and Users. All Staff and Users holding a personal dosimeter were informed by the Bulletin and by a personal e-mail sent in February 2008 that they were required to participate in the course before the annual exchange of their dosimeter. Many people had not done so by that time and the Dosimetry Service exceptionally classified them for 2 months as short-term visitors (VCT), a category of monitored personnel to whom the training requirement does not presently apply. As all personnel concerned have since had time to participate in an RP course, this "grace period" will no longer be granted as of 1 October 2008 and the RP course must be completed before the personal dosimeter is exchanged. For newcomers to CERN, and for those returning to CERN after an absence of more than 1 year, one registration as a VCT for two months ...

  2. Visualizing dipole radiation

    Science.gov (United States)

    Girwidz, Raimund V.

    2016-11-01

    The Hertzian dipole is fundamental to the understanding of dipole radiation. It provides basic insights into the genesis of electromagnetic waves and lays the groundwork for an understanding of half-wave antennae and other types. Equations for the electric and magnetic fields of such a dipole can be derived mathematically. However these are very abstract descriptions. Interpreting these equations and understanding travelling electromagnetic waves are highly limited in that sense. Visualizations can be a valuable supplement that vividly present properties of electromagnetic fields and their propagation. The computer simulation presented below provides additional instructive illustrations for university lectures on electrodynamics, broadening the experience well beyond what is possible with abstract equations. This paper refers to a multimedia program for PCs, tablets and smartphones, and introduces and discusses several animated illustrations. Special features of multiple representations and combined illustrations will be used to provide insight into spatial and temporal characteristics of field distributions—which also draw attention to the flow of energy. These visualizations offer additional information, including the relationships between different representations that promote deeper understanding. Finally, some aspects are also illustrated that often remain unclear in lectures.

  3. Smart Radiation Therapy Biomaterials.

    Science.gov (United States)

    Ngwa, Wilfred; Boateng, Francis; Kumar, Rajiv; Irvine, Darrell J; Formenti, Silvia; Ngoma, Twalib; Herskind, Carsten; Veldwijk, Marlon R; Hildenbrand, Georg Lars; Hausmann, Michael; Wenz, Frederik; Hesser, Juergen

    2017-03-01

    Radiation therapy (RT) is a crucial component of cancer care, used in the treatment of over 50% of cancer patients. Patients undergoing image guided RT or brachytherapy routinely have inert RT biomaterials implanted into their tumors. The single function of these RT biomaterials is to ensure geometric accuracy during treatment. Recent studies have proposed that the inert biomaterials could be upgraded to "smart" RT biomaterials, designed to do more than 1 function. Such smart biomaterials include next-generation fiducial markers, brachytherapy spacers, and balloon applicators, designed to respond to stimuli and perform additional desirable functions like controlled delivery of therapy-enhancing payloads directly into the tumor subvolume while minimizing normal tissue toxicities. More broadly, smart RT biomaterials may include functionalized nanoparticles that can be activated to boost RT efficacy. This work reviews the rationale for smart RT biomaterials, the state of the art in this emerging cross-disciplinary research area, challenges and opportunities for further research and development, and a purview of potential clinical applications. Applications covered include using smart RT biomaterials for boosting cancer therapy with minimal side effects, combining RT with immunotherapy or chemotherapy, reducing treatment time or health care costs, and other incipient applications. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Radiation hazard control report

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Taeko; Inagaki, Masayo; Morishima, Hiroshige; Araki, Yasusuke; Takiguchi, Chizuko; Hiraji, Chihiro; Nagai, Shoya [Kinki Univ., Higashi-Osaka, Osaka (Japan)

    2003-03-01

    The document of radiation hazard control from April 2001 to March 2002 in the research institute of atomic energy of Kinki University was reported and actual data were presented. 106 personnel were subjected to the control, the reactor maximal output was 1W with total output of 399,64 W center dot h for total 718.23 h and the institute underwent the inspection by Ministry of Education, Culture, Sports, Science and Technology for twice, which resulting in getting satisfactory evaluation. The control involved was for the personnel, laboratories and field. The first was done mainly with film badges and sometimes with pocket dosimeters, and revealed the exposure of 0.480 mSv at maximum. The laboratory dose equivalent was continuously measured with the ionization chamber area monitor and sometimes with the ionization chamber survey meters, GM tube survey meters and scintillation survey meters. The film badge and TLD were also used. In addition, concentrations of radioactivity were measured in the exhaust gas and water with the dust-monitor and overall-monitor, respectively, and surface densities by smear-method with 2 pi-gas flow and liquid scintillation counters. The field control was carried out by calculation of environmental gamma-ray dose equivalent rate based on monthly TLD dose data and by actual beta-ray measurement of environmental specimens collected at every 3 months. (J.P.N.)

  5. Radiation hazard control report

    Energy Technology Data Exchange (ETDEWEB)

    Koga, Taeko; Inagaki, Masayo; Morishima, Hiroshige; Araki, Yasusuke; Takiguchi, Chizuko; Matsubayashi, Hideki; Hiraji, Chihiro [Kinki Univ., Higashi-Osaka, Osaka (Japan)

    2002-01-01

    The document of radiation hazard control from April 2000 to March 2001 in the research institute of atomic energy of Kinki University was reported and actual data were presented. Seventy five personnel were subjected to the control, the reactor maximal output was 1W with total output of 463.74 W center dot h for total 777.34 h and the institute underwent the inspection by Science and Technology Agency for 3 times, which resulting in getting satisfactory evaluation. The control involved was for the personnel, laboratories and field. The first was done mainly with film badges and sometimes with pocket dosimeters, and revealed the exposure of 0.264 mSv at maximum. The laboratory dose equivalent was continuously measured with the ionization chamber area monitor and sometimes with the ionization chamber survey meters, GM tube survey meters and scintillation survey meters. The film badge and TLD were also used. In addition, concentrations of radioactivity were measured in the exhaust gas and water with the dust-monitor and overall-monitor, respectively, and surface densities by smear-method with the 2 pi-gas flow and liquid scintillation counters. The field control was carried out by calculation of environmental gamma-ray dose equivalent rate based on monthly TLD dose data and by actual beta-ray measurement of environmental specimens collected at every 3 months. (J.P.N.)

  6. Radiation treatment of molasses

    Science.gov (United States)

    Rodríguez, A. S.; Serrano G., J.; Lara R., O.; Reyes L., J.

    Molasses are a by-product of the sugar industry. Their annual production in México in around 1 million tons and are mainly used as a complement for animal feeding and for the production of alcohols. Their value is relatively low compared with another chemicals. When molasses are irradiated with gamma radiation or accelerated electrons, in presence of nitric acid and oxygen, it is obtained oxalic acid and several polymeric compounds. In both cases, the same products are obtained, but the yield is greater with electrons. It has been studied the effect of dose and dose rate in the yields. As example, when mixtures of molasses-nitric acid, with an initial concentration of 26% of total sugar reductors, are irradiated with 1.0 MeV electrons, in a continuous flow reactor, at 0.11 {Gy}/{sec} to a total dose of 30 KGy, the oxalic acid yield is around 44% of the total chemical reductors used. The separations of the radiolytic products was made by successive decantations and concentrations, and purified by recristallizations. From the analytical information, the minimal formula were calculated for the acid product and the polymeric compounds.

  7. Application of radiation in Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Naiyyum Choudhury; Najmul Alam Chowdhury; Feroza Akhtar [Bangladesh Atomic Energy Commission, Dhaka (Bangladesh)

    2001-03-01

    Radiation technology offers a very wide scope for utilisation and commercial exploitation in various field. All over the world, this technology is being favourably considered for different applications like radiation sterilisation of medical products, preservation of food by controlling the physiological processes for extending shelf-life and eradication of microbial and insect pests, radiation processing of polymeric materials and treatment of sewage sludge. Bangladesh Atomic Energy Commission has taken radiation processing programmes in a big way right from its inception. This paper describes the studies carried out by various research groups in Bangladesh Atomic Energy Commission mainly using Cobalt-60 gamma radiation. The investigation covers medical sterilisation, food preservation and development and modification of polymeric materials by gamma radiation. Both food preservation and radiation sterilisation of medical products are now being commercially carried out in the Gammatech facility as a joint venture company of BAEC and a private entrepreneur. Bangladesh is soon going to establish a full-fledged Tissue Bank to cater the needs of various tissue allografts for surgical replacement. Recently Government of Bangladesh has allocated US$ 1.00 million for strengthening of the Tissue Banking Laboratory. BAEC has made quite a good research contribution on vulcanization of natural rubber latex, wood plastic composites, surface coating curing, polymer modification etc. As a result of successful achievement of R and D activities in all these projects, a pilot plant project involving about US$ 4.00 million is under implementation at the Atomic energy Research Establishment campus of BAEC. In addition a project on 'National Polymer Centre' at a cost of US$ 2.00 million has already been approved. It is expected that work on radiation processing including commercialization will be accelerated with the implementation of these projects. The impact of radiation

  8. Radiosensitizers, radioprotectors, and radiation mitigators

    Directory of Open Access Journals (Sweden)

    Jayam Raviraj

    2014-01-01

    Full Text Available Radiotherapy is regarded as one of the most important therapeutic modality for the treatment of malignant lesions. This field is undergoing rapid advancements in the recent times. With the use of radiosensitizers and radioprotective agents, the course of radiotherapy has improved the sensitization of tumor cells and protection of normal cells, respectively. The aim of this paper was to critically review and analyze the available compounds used as radiosensitizers, radioprotectors, and radiation mitigators. For reviewing, the author used the electronic search for the keywords ′Radiosensitizers′, ′Radioprotectors′, ′Radiation mitigators′ on PubMed for inclusion of previously published articles and further search of reference papers on individual radiosensitizing and radioprotecting agents was done. Radiosensitizers are agents that sensitize the tumor cells to radiation. These compounds apparently promote fixation of the free radicals produced by radiation damage at the molecular level. The mechanism of action is similar to the oxygen effect, in which biochemical reactions in the damaged molecules prevent repair of the cellular radiation damage. Free radicals such as OH + are captured by the electron affinity of the radiosensitizers, rendering the molecules incapable of repair. Radioprotectors are compounds that are designed to reduce the damage in normal tissues caused by radiation. These compounds are often antioxidants and must be present before or at the time of radiation for effectiveness. Other agents, termed mitigators, may be used to minimize toxicity even after radiation has been delivered. This article tries to discuss the various aspects of radiosensitizers, radioprotectors, and radiation mitigators including the newer agents.

  9. Atmospheric radiation flight dose rates

    Science.gov (United States)

    Tobiska, W. K.

    2015-12-01

    Space weather's effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun's photons, particles, and fields. Of the domains that are affected by space weather, the coupling between the solar and galactic high-energy particles, the magnetosphere, and atmospheric regions can significantly affect humans and our technology as a result of radiation exposure. Space Environment Technologies (SET) has been conducting space weather observations of the atmospheric radiation environment at aviation altitudes that will eventually be transitioned into air traffic management operations. The Automated Radiation Measurements for Aerospace Safety (ARMAS) system and Upper-atmospheric Space and Earth Weather eXperiment (USEWX) both are providing dose rate measurements. Both activities are under the ARMAS goal of providing the "weather" of the radiation environment to improve aircraft crew and passenger safety. Over 5-dozen ARMAS and USEWX flights have successfully demonstrated the operation of a micro dosimeter on commercial aviation altitude aircraft that captures the real-time radiation environment resulting from Galactic Cosmic Rays and Solar Energetic Particles. The real-time radiation exposure is computed as an effective dose rate (body-averaged over the radiative-sensitive organs and tissues in units of microsieverts per hour); total ionizing dose is captured on the aircraft, downlinked in real-time, processed on the ground into effective dose rates, compared with NASA's Langley Research Center (LaRC) most recent Nowcast of Atmospheric Ionizing Radiation System (NAIRAS) global radiation climatology model runs, and then made available to end users via the web and smart phone apps. Flight altitudes now exceed 60,000 ft. and extend above commercial aviation altitudes into the stratosphere. In this presentation we describe recent ARMAS and USEWX results.

  10. Radiative effects in radiative shocks in shock tubes

    Science.gov (United States)

    Drake, R. P.; Doss, F. W.; McClarren, R. G.; Adams, M. L.; Amato, N.; Bingham, D.; Chou, C. C.; DiStefano, C.; Fidkowski, K.; Fryxell, B.; Gombosi, T. I.; Grosskopf, M. J.; Holloway, J. P.; van der Holst, B.; Huntington, C. M.; Karni, S.; Krauland, C. M.; Kuranz, C. C.; Larsen, E.; van Leer, B.; Mallick, B.; Marion, D.; Martin, W.; Morel, J. E.; Myra, E. S.; Nair, V.; Powell, K. G.; Rauchwerger, L.; Roe, P.; Rutter, E.; Sokolov, I. V.; Stout, Q.; Torralva, B. R.; Toth, G.; Thornton, K.; Visco, A. J.

    2011-09-01

    Using modern high-energy-density facilities it is straightforward to produce radiative shock waves in which the transfer of energy by radiation controls the hydrodynamic structure of the system. Some of these experiments use shock tubes. This paper discusses such experiments, with an emphasis on the simple physical relations that determine the primary features of such shocks and on the details and impact of radiative energy transfer in such systems. Notable aspects include the creation of high-density shocked layers, the flow of radiative energy toward regions of higher energy density, and the creation of secondary shocks by ablation of the tube walls ahead of the primary shock front. Simulations of one such experimental system are also shown.

  11. Radiation Chemistry and the Radiation Preservation of Food.

    Science.gov (United States)

    Taub, Irwin A.

    1981-01-01

    Describes common features in the radiation chemistry of food components, and illustrates how product yields are predicted. Presents data that pertain to the radiolysis of the nitrate ion, metmyoglobin, myosin, and tripalmitin. (CS)

  12. Radiation Chemistry and the Radiation Preservation of Food.

    Science.gov (United States)

    Taub, Irwin A.

    1981-01-01

    Describes common features in the radiation chemistry of food components, and illustrates how product yields are predicted. Presents data that pertain to the radiolysis of the nitrate ion, metmyoglobin, myosin, and tripalmitin. (CS)

  13. Sky Radiometers on Stand for Downwelling Radiation

    Data.gov (United States)

    Oak Ridge National Laboratory — The Sky Radiation (SKYRAD) collection of radiometers provides each Atmospheric Radiation and Cloud Station (ARCS) with continuous measurements of broadband shortwave...

  14. Novel Technology for Radiation Protection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Radiation exposure to living tissue generates free radicals through ionizing reaction such as photoelectric effect, Compton and Auger effects.  Radiation...

  15. Radiative transfer on discrete spaces

    CERN Document Server

    Preisendorfer, Rudolph W; Stark, M; Ulam, S

    1965-01-01

    Pure and Applied Mathematics, Volume 74: Radiative Transfer on Discrete Spaces presents the geometrical structure of natural light fields. This book describes in detail with mathematical precision the radiometric interactions of light-scattering media in terms of a few well established principles.Organized into four parts encompassing 15 chapters, this volume begins with an overview of the derivations of the practical formulas and the arrangement of formulas leading to numerical solution procedures of radiative transfer problems in plane-parallel media. This text then constructs radiative tran

  16. Solar and infrared radiation measurements

    CERN Document Server

    Vignola, Frank; Michalsky, Joseph

    2012-01-01

    The rather specialized field of solar and infrared radiation measurement has become more and more important in the face of growing demands by the renewable energy and climate change research communities for data that are more accurate and have increased temporal and spatial resolution. Updating decades of acquired knowledge in the field, Solar and Infrared Radiation Measurements details the strengths and weaknesses of instruments used to conduct such solar and infrared radiation measurements. Topics covered include: Radiometer design and performance Equipment calibration, installation, operati

  17. Synchrotron radiation and structural proteomics

    CERN Document Server

    Pechkova, Eugenia

    2011-01-01

    This book presents an overview of the current state of research in both synchrotron radiation and structural proteomics from different laboratories worldwide. The book presents recent research results in the most advanced methods of synchrotron radiation analysis, protein micro- and nano crystallography, X-ray scattering and X-ray optics, coherent X-Ray diffraction, and laser cutting and contactless sample manipulation are described in details. The book focuses on biological applications and highlights important aspects such as radiation damage and molecular modeling.

  18. The radiation chemistry of macromolecules

    CERN Document Server

    1973-01-01

    The Radiation Chemistry of Macromolecules, Volume II is a collection of papers that discusses radiation chemistry of specific systems. Part 1 deals with radiation chemistry of substituted vinyl polymers, particularly polypropylene (PP) as its structure is intermediate between polyethylene and polyisobutylene. This part also discusses polypropylene oxide (PPOx) for it can be prepared in the atactic, isotactic, and optically active forms. One paper focuses on the fundamental chemical processes and the changes in physical properties that give rise to many different applications of polystyrene. An

  19. Sommerfeld radiation condition at threshold

    DEFF Research Database (Denmark)

    Skibsted, Erik

    We prove Besov space bounds of the resolvent at low energies in any dimension for a class of potentials that are negative and obey a virial condition with these conditions imposed at infinity only. We do not require spherical symmetry. The class of potentials includes in dimension ≥ 3 the attract...... the attractive Coulomb potential. There are two boundary values of the resolvent at zero energy which we characterize by radiation conditions. These radiation conditions are zero energy versions of the well-known Sommerfeld radiation condition....

  20. Thermopile detector radiation hard readout

    Science.gov (United States)

    Gaalema, Stephen; Van Duyne, Stephen; Gates, James L.; Foote, Marc C.

    2010-08-01

    The NASA Jupiter Europa Orbiter (JEO) conceptual payload contains a thermal instrument with six different spectral bands ranging from 8μm to 100μm. The thermal instrument is based on multiple linear arrays of thermopile detectors that are intrinsically radiation hard; however, the thermopile CMOS readout needs to be hardened to tolerate the radiation sources of the JEO mission. Black Forest Engineering is developing a thermopile readout to tolerate the JEO mission radiation sources. The thermal instrument and ROIC process/design techniques are described to meet the JEO mission requirements.

  1. Ocular neuromyotonia after radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lessell, S.; Lessell, I.M.; Rizzo, J.F. III

    1986-12-15

    Ocular neuromyotonia is a paroxysmal monocular deviation that results from spasm of eye muscles secondary to spontaneous discharges from third, fourth, or sixth nerve axons. We observed this rare disorder in four patients who had been treated with radiation for tumors in the region of the sella turcica and cavernous sinus. Based on these cases and four others identified in the literature it would appear that radiation predisposes to a cranial neuropathy in which ocular neuromyotonia may be the major manifestation. Radiation appears to be the most common cause of ocular neuromyotonia.

  2. Radiation biology of medical imaging

    CERN Document Server

    Kelsey, Charles A; Sandoval, Daniel J; Chambers, Gregory D; Adolphi, Natalie L; Paffett, Kimberly S

    2014-01-01

    This book provides a thorough yet concise introduction to quantitative radiobiology and radiation physics, particularly the practical and medical application. Beginning with a discussion of the basic science of radiobiology, the book explains the fast processes that initiate damage in irradiated tissue and the kinetic patterns in which such damage is expressed at the cellular level. The final section is presented in a highly practical handbook style and offers application-based discussions in radiation oncology, fractionated radiotherapy, and protracted radiation among others. The text is also supplemented by a Web site.

  3. Review of solar radiation utilizability

    Science.gov (United States)

    Klein, S. A.; Beckman, W. A.

    1984-11-01

    A development history is presented for the concept and methodology of solar radiation 'utilizability', which is defined as the fraction of solar radiation that is incident on a surface exceeding a specified threshold or critical level. The concept, which was initially applied to flat plate solar collector thermal performance calculations, has more recently been applied to systems with concentrating collectors as well as to passive and photovoltaic systems. The utilizability function also contains information about operating times through its derivative with respect to critical level. Existing utilizability correlations provide a simple and elegant means of estimating the long term effect of solar radiation on any solar process.

  4. Radiation-induced Genomic Instability and Radiation Sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Varnum, Susan M.; Sowa, Marianne B.; Kim, Grace J.; Morgan, William F.

    2013-01-19

    The obvious relationships between reactive oxygen and nitrogen species, mitochondrial dysfunction, inflammatory type responses and reactive chemokines and cytokines suggests a general stress response induced by ionizing radiation most likely leads to the non-targeted effects described after radiation exposure. We argue that true bystander effects do not occur in the radiation therapy clinic. But there is no question that effects outside the target volume do occur. These “out of field effects” are considered very low dose effects in the context of therapy. So what are the implications of non-targeted effects on radiation sensitivity? The primary goal of therapy is to eradicate the tumor. Given the genetic diversity of the human population, lifestyle and environment factors it is likely some combination of these will influence patient outcome. Non-targeted effects may contribute to a greater or lesser extent. But consider the potential situation involving a partial body exposure due to a radiation accident or radiological terrorism. Non-targeted effects suggest that the tissue at risk for demonstrating possible detrimental effects of radiation exposure might be greater than the volume actually irradiated.

  5. Boundary conditions for NLTE polarized radiative transfer with incident radiation

    CERN Document Server

    Faurobert, Marianne; Atanackovic, Olga

    2013-01-01

    Polarized NLTE radiative transfer in the presence of scattering in spectral lines and/or in continua may be cast in a so-called reduced form for six reduced components of the radiation field. In this formalism the six components of the reduced source function are angle-independent quantities. It thus reduces drastically the storage requirement of numerical codes. This approach encounters a fundamental problem when the medium is illuminated by a polarized incident radiation, because there is a priori no way of relating the known (and measurable) Stokes parameters of the incident radiation to boundary conditions for the reduced equations. The origin of this problem is that there is no unique way of deriving the radiation reduced components from its Stokes parameters (only the inverse operation is clearly defined). The method proposed here aims at enabling to work with arbitrary incident radiation field (polarized or unpolarized). In previous works an ad-hoc treatment of the boundary conditions, applying to case...

  6. Radiation effects on structural materials

    Energy Technology Data Exchange (ETDEWEB)

    Ghoniem, N.M.

    1991-06-28

    This report discusses the following topics on the effect radiation has on thermonuclear reactor materials: Atomic Displacements; Microstructure Evolution; Materials Engineering, Mechanics, and Design; Research on Low-Activation Steels; and Research Motivated by Grant Support.

  7. The LISA Pathfinder Radiation Monitor

    Science.gov (United States)

    Wass, P. J.; Araújo, H.; Boatella, C.; Chmeissani, M.; Hajdas, W.; Lobo, A.; Puigdengoles, C.; Sumner, T.

    2006-11-01

    We present the concept, design and testing of the radiation monitor for LISA Pathfinder. Galactic cosmic rays (GCRs) and solar energetic particles (SEPs) will cause charging of the LISA Pathfinder test masses producing unwanted disturbances which could be significant during a large solar eruption. A radiation monitor on board LISA Pathfinder, using silicon PIN diodes as particle detectors, will measure the particle flux responsible for charging. It will also be able to record spectral information to identify solar energetic particle events. The design of the monitor was supported by Monte Carlo simulations which allow detailed predictions of the radiation monitor performance. We present these predictions as well as the results of high-energy proton tests carried out at the Paul Scherrer Institute, Switzerland. The tests show good agreement with our simulations and confirm the capability of the radiation monitor to perform well in the space environment, meeting all science requirements.

  8. Multiple-mode radiation detector

    Energy Technology Data Exchange (ETDEWEB)

    Claus, Liam D.; Derzon, Mark S.; Kay, Randolph R.; Bauer, Todd; Trotter, Douglas Chandler; Henry, Michael David

    2015-08-25

    An apparatus for detecting radiation is provided. In embodiments, at least one sensor medium is provided, of a kind that interacts with radiation to generate photons and/or charge carriers. The apparatus also includes at least one electrode arrangement configured to collect radiation-generated charge from a sensor medium that has been provided. The apparatus also includes at least one photodetector configured to produce an electrical output in response to photons generated by radiation in such a sensor medium, and an electronic circuit configured to produce an output that is jointly responsive to the collected charge and to the photodetector output. At least one such electrode arrangement, at least one such photodetector, and at least one such sensor medium are combined to form an integral unit.

  9. Nuclear Radiation and the Thyroid

    Science.gov (United States)

    American Thyroid Association ® www.thyroid.org Nuclear Radiation and the Thyroid What is the thyroid gland? The thyroid gland is a butterfly-shaped endocrine gland that is normally located in the ...

  10. Radiation Resources Outside of EPA

    Science.gov (United States)

    EPA does not license nuclear power plants or regulate the non-ionizing radiation from cell phones, smart meters or power lines. This page provides links to the state and federal agencies that regulate these matters.

  11. Quality Indicators in Radiation Oncology

    Energy Technology Data Exchange (ETDEWEB)

    Albert, Jeffrey M. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Das, Prajnan, E-mail: prajdas@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-03-15

    Oncologic specialty societies and multidisciplinary collaborative groups have dedicated considerable effort to developing evidence-based quality indicators (QIs) to facilitate quality improvement, accreditation, benchmarking, reimbursement, maintenance of certification, and regulatory reporting. In particular, the field of radiation oncology has a long history of organized quality assessment efforts and continues to work toward developing consensus quality standards in the face of continually evolving technologies and standards of care. This report provides a comprehensive review of the current state of quality assessment in radiation oncology. Specifically, this report highlights implications of the healthcare quality movement for radiation oncology and reviews existing efforts to define and measure quality in the field, with focus on dimensions of quality specific to radiation oncology within the “big picture” of oncologic quality assessment efforts.

  12. Electricity generation using electromagnetic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Halas, Nancy J.; Nordlander, Peter; Neumann, Oara

    2017-08-22

    In general, in one aspect, the invention relates to a system to create vapor for generating electric power. The system includes a vessel comprising a fluid and a complex and a turbine. The vessel of the system is configured to concentrate EM radiation received from an EM radiation source. The vessel of the system is further configured to apply the EM radiation to the complex, where the complex absorbs the EM radiation to generate heat. The vessel of the system is also configured to transform, using the heat generated by the complex, the fluid to vapor. The vessel of the system is further configured to sending the vapor to a turbine. The turbine of the system is configured to receive, from the vessel, the vapor used to generate the electric power.

  13. GEWEX Surface Radiation Budget (SRB)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NASA/GEWEX Surface Radiation Budget (SRB) Release-3.0 data sets contains global 3-hourly, daily, monthly/3-hourly, and monthly averages of surface and top-of...

  14. Severe small bowel radiation enteritis

    Energy Technology Data Exchange (ETDEWEB)

    Jaen, J.; Santos, J.A.; Carrion, J.R.; Garcia, P. (Hospital General Gregorio Maranon, Madrid (Spain))

    1989-01-01

    We have during recent years observed 8 patients with serious radiation injury to the small intestine. As the cases are quite illustrative, their symptomatology is briefly reported and the treatment and possible predisposing factors are analysed. (orig./MG).

  15. Radiation reaction in various dimensions

    CERN Document Server

    Galtsov, D V

    2002-01-01

    We discuss the radiation reaction problem for an electric charge moving in flat space-time of arbitrary dimensions. It is shown that four is the unique dimension where a local differential equation exists accounting for the radiation reaction and admitting a consistent mass-renormalization (the Dirac-Lorentz equation). In odd dimensions the Huygens principle does not hold; as a result, the radiation reaction force depends on the whole past history of a charge (radiative tail). We show that the divergence in the tail integral can be removed by the mass renormalization only in the 2+1 theory. In even dimensions higher than four, divergences can not be removed by a renormalization.

  16. Sarcoma risk after radiation exposure

    Directory of Open Access Journals (Sweden)

    Berrington de Gonzalez Amy

    2012-10-01

    Full Text Available Abstract Sarcomas were one of the first solid cancers to be linked to ionizing radiation exposure. We reviewed the current evidence on this relationship, focusing particularly on the studies that had individual estimates of radiation doses. There is clear evidence of an increased risk of both bone and soft tissue sarcomas after high-dose fractionated radiation exposure (10 + Gy in childhood, and the risk increases approximately linearly in dose, at least up to 40 Gy. There are few studies available of sarcoma after radiotherapy in adulthood for cancer, but data from cancer registries and studies of treatment for benign conditions confirm that the risk of sarcoma is also increased in this age-group after fractionated high-dose exposure. New findings from the long-term follow-up of the Japanese atomic bomb survivors suggest, for the first time, that sarcomas can be induced by acute lower-doses of radiation (

  17. Ethical issues in radiation protection

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Lars (ed.)

    2000-03-15

    Ethical theories are relevant to the current recommendations and standards for radiation protection. Radiation protection is not only a matter for science. It is also a problem of philosophy. In order for protection regulations to be respected, it must correspond to widely accepted ethical values among those who are affected by the regulations. The workshop covered the following issues: Problems in Present Protection Policy, ICRP Protection Policy - A Historical Perspective, Radiation Risk - What we know and what we believe, Present ICRP Recommendations, Ethical Values in the Context of ICRP Recommendations, Collective Responsibility for Invisible Harm, Environmental Protection - Ethical Issues, The Global Change of Values, and Procedural justice and Radiation Protection. Six workshop contributions and a workshop summary are presented in this report.

  18. Stackable Radiation Hardened FRAM Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Purpose of this effort was to offer a novel solution to the pressing need for radiation tolerant memory for the demanding satellite and space probe worldwide...

  19. Radiation Effects on Polymers - XI

    DEFF Research Database (Denmark)

    Ghanem, N. A.; El-Awady, N. I.; Singer, Klaus Albert Julius;

    1979-01-01

    With the aim of improving properties of cellulose acetate membranes for reverse osmosis desalination, grafting was performed using high energy electrons. In this paper, the grafting parameters (radiation dose and method, monomer concentration, solvents, chain transfer agent and redox system...

  20. Documentation requirements for radiation sterilization

    DEFF Research Database (Denmark)

    Miller, A.

    1995-01-01

    Several standards are recently approved or are under development by the standard organizations ISO and CEN in the field of radiation sterilization. Particularly in Europe these standards define new requirements on some issues and on other issues they emphasize the necessary documentation for appr......Several standards are recently approved or are under development by the standard organizations ISO and CEN in the field of radiation sterilization. Particularly in Europe these standards define new requirements on some issues and on other issues they emphasize the necessary documentation...... for approval of radiation sterilized products. The impact of these standards on the radiation sterilization is discussed, with special attention given to a few special issues, mainly traceability and uncertainty of measurement results....