WorldWideScience

Sample records for greatly reducing radiation

  1. Southern Great Plains Atmospheric Radiation Measurement Site

    Data.gov (United States)

    Federal Laboratory Consortium — The Southern Great Plains Atmospheric Radiation Measurement Site (SGP-ARM) is the oldest and largest of DOE's Arm sites. It was established in 1992. It consists of...

  2. The great advances in radiation measurements

    International Nuclear Information System (INIS)

    Brodsky, A.

    2002-01-01

    The title of this banquet talk was selected to entertain conferees with recollections of major advances in dosimetry that have stimulated appetites for scientific progress. Recalling over fifty years of use of dosimetric instruments and concepts in the 1950-2000 era leads to an appreciation of many advances in solid state dosimetry, which others here know well and pursue vigorously. This author has been mainly a user, admirer, and interpreter of the fundamental methods of dose measurement. These advances have allowed ease of application in radiation protection and medical physics, for determining current routine and accidental exposures to workers, and for precise radiotherapeutic dose delivery. In more recent years, advances in identifying means of locating selective depositions of energy in various materials are providing ways of retrospectively assessing doses to tissue that were deposited many years ago. These methods also will allow development of quantitative theories of radiation damage once the lesions of interest are identified through further advances in molecular genetics. Yet, reflections on the past fifty years lead to increasing appreciation of the enormous achievements of our predecessors in the 1900-1950 period. Therefore, this presentation emphasises methods used by the author and some of his data interpretations during his 52-year career, with some examination of the earlier origin of some of these methods. (author)

  3. Attribute amnesia is greatly reduced with novel stimuli

    Directory of Open Access Journals (Sweden)

    Weijia Chen

    2017-11-01

    Full Text Available Attribute amnesia is the counterintuitive phenomenon where observers are unable to report a salient aspect of a stimulus (e.g., its colour or its identity immediately after the stimulus was presented, despite both attending to and processing the stimulus. Almost all previous attribute amnesia studies used highly familiar stimuli. Our study investigated whether attribute amnesia would also occur for unfamiliar stimuli. We conducted four experiments using stimuli that were highly familiar (colours or repeated animal images or that were unfamiliar to the observers (unique animal images. Our results revealed that attribute amnesia was present for both sets of familiar stimuli, colour (p < .001 and repeated animals (p = .001; but was greatly attenuated, and possibly eliminated, when the stimuli were unique animals (p = .02. Our data shows that attribute amnesia is greatly reduced for novel stimuli.

  4. Has the great recession and its aftermath reduced traffic fatalities?

    Science.gov (United States)

    Noland, Robert B; Zhou, Yuhan

    2017-01-01

    An analysis of state-level data from 1984 to 2014 provides evidence on the relationship between economic recessions and US traffic fatalities. While there are large reductions associated with decreases in household median income, other policy variables tend to have additional and in some cases, larger effects. An increase in the inequality of the income distribution, measured by the Gini index, has reduced traffic fatalities. Graduated licensing policies, cell phone laws, and motorcycle helmet requirements are all associated with reductions in fatalities. Other factors include a proxy for medical technology, and access to emergency medical services (based on the percent of vehicle miles traveled in rural areas); reductions in the latter accounted for a substantial reduction in fatalities and is likely another indicator of reduced economic activity. Changes in the road network, mainly increases in the percent of collector roads has increased fatalities. Population growth is associated with increased traffic fatalities and changes in age cohorts has a small negative effect. Overall, results suggest that there has been a beneficial impact on traffic fatalities from reduced economic activity, but various policies adopted by the states have also reduced traffic fatalities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. State of damage of radiation facilities in great Hanshin earthquake

    International Nuclear Information System (INIS)

    1995-01-01

    The southern Hyogo Prefecture earthquake of magnitude 7.2 occurred in the early morning of January 17, 1995. The outline of the earthquake and dead and injured, the damages of buildings, life lines, roads, railways and harbors, liquefaction phenomena, the state of occurrence of fires and so on are reported. The districts where the earthquakes of magnitude 5 or stronger occurred, and the radiation facilities in those districts are shown. The state of damage of radiation facilities in past earthquakes is summarized. From January 17 to 19 after the earthquake, Science and Technology Agency gave necessary instruction to and heard the state of damage from 79 permitted facilities in the areas of magnitude 7 or 6 by telephone, and received the report that there was not the fear of radiation damage in all facilities. Also the state of damage of radiation facilities was investigated at the actual places, and the questionnaires on the state of radiation facilities and the action at the time of the earthquake were performed. The state of radiation facilities accompanying the earthquake is reported. The matters to be reflected to the countermeasures to earthquakes anew for the protection of facilities, communication system, facility checkup system and the resumption of use are pointed out. (K.I.)

  6. Reducing occupational radiation exposures at LWRs

    International Nuclear Information System (INIS)

    Lattanzi, D.; Neri, C.; Papa, C.; Paribelli, S.

    1980-01-01

    The occupational radiation doses received by nuclear power plant personnel during a period of several years of operation are briefly reviewed. Comparisons are made between the data for BWRs and PWRs in order to identify the more ''critical'' reactor type, from a radiological poin; of view. Attention is also devoted to GCRs. Furthermore the areas which contribute most to personnel doses are considered and briefly reviewed. The main steps to be taken in order to reduce occupational radiation exposures at LWRs are discussed. (H.K.)

  7. Concern over radiation exposure and psychological distress among rescue workers following the Great East Japan Earthquake

    Directory of Open Access Journals (Sweden)

    Matsuoka Yutaka

    2012-05-01

    Full Text Available Abstract Background On March 11, 2011, the Great East Japan Earthquake and tsunami that followed caused severe damage along Japans northeastern coastline and to the Fukushima Daiichi nuclear power plant. To date, there are few reports specifically examining psychological distress in rescue workers in Japan. Moreover, it is unclear to what extent concern over radiation exposure has caused psychological distress to such workers deployed in the disaster area. Methods One month after the disaster, 424 of 1816 (24% disaster medical assistance team workers deployed to the disaster area were assessed. Concern over radiation exposure was evaluated by a single self-reported question. General psychological distress was assessed with the Kessler 6 scale (K6, depressive symptoms with the Center for Epidemiologic Studies Depression Scale (CES-D, fear and sense of helplessness with the Peritraumatic Distress Inventory (PDI, and posttraumatic stress symptoms with the Impact of Event Scale-Revised (IES-R. Results Radiation exposure was a concern for 39 (9.2% respondents. Concern over radiation exposure was significantly associated with higher scores on the K6, CES-D, PDI, and IES-R. After controlling for age, occupation, disaster operation experience, duration of time spent watching earthquake news, and past history of psychiatric illness, these associations remained significant in men, but did not remain significant in women for the CES-D and PDI scores. Conclusion The findings suggest that concern over radiation exposure was strongly associated with psychological distress. Reliable, accurate information on radiation exposure might reduce deployment-related distress in disaster rescue workers.

  8. New technologies to reduce pediatric radiation doses

    International Nuclear Information System (INIS)

    Bernhardt, Philipp; Lendl, Markus; Deinzer, Frank

    2006-01-01

    X-ray dose reduction in pediatrics is particularly important because babies and children are very sensitive to radiation exposure. We present new developments to further decrease pediatric patient dose. With the help of an advanced exposure control, a constant image quality can be maintained for all patient sizes, leading to dose savings for babies and children of up to 30%. Because objects of interest are quite small and the speed of motion is high in pediatric patients, short pulse widths down to 4 ms are important to reduce motion blurring artifacts. Further, a new noise-reduction algorithm is presented that detects and processes signal and noise in different frequency bands, generating smooth images without contrast loss. Finally, we introduce a super-resolution technique: two or more medical images, which are shifted against each other in a subpixel region, are combined to resolve structures smaller than the size of a single pixel. Advanced exposure control, short exposure times, noise reduction and super-resolution provide improved image quality, which can also be invested to save radiation exposure. All in all, the tools presented here offer a large potential to minimize the deterministic and stochastic risks of radiation exposure. (orig.)

  9. Great Tits (Parus major) reduce caterpillar damage in commercial apple orchards

    NARCIS (Netherlands)

    Mols, C.M.M.; Visser, M.E.

    2007-01-01

    Alternative ways to control caterpillar pests and reduce the use of pesticides in apple orchards are in the interest of the environment, farmers and the public. Great tits have already been shown to reduce damage under high caterpillar density when breeding in nest boxes in an experimental apple

  10. Environmental assessment for the Atmospheric Radiation Measurement (ARM) Program: Southern Great Plains Cloud and Radiation Testbed (CART) site

    International Nuclear Information System (INIS)

    Policastro, A.J.; Pfingston, J.M.; Maloney, D.M.; Wasmer, F.; Pentecost, E.D.

    1992-03-01

    The Atmospheric Radiation Measurement (ARM) Program is aimed at supplying improved predictive capability of climate change, particularly the prediction of cloud-climate feedback. The objective will be achieved by measuring the atmospheric radiation and physical and meteorological quantities that control solar radiation in the earth's atmosphere and using this information to test global climate and related models. The proposed action is to construct and operate a Cloud and Radiation Testbed (CART) research site in the southern Great Plains as part of the Department of Energy's Atmospheric Radiation Measurement Program whose objective is to develop an improved predictive capability of global climate change. The purpose of this CART research site in southern Kansas and northern Oklahoma would be to collect meteorological and other scientific information to better characterize the processes controlling radiation transfer on a global scale. Impacts which could result from this facility are described

  11. Environmental assessment for the Atmospheric Radiation Measurement (ARM) Program: Southern Great Plains Cloud and Radiation Testbed (CART) site

    Energy Technology Data Exchange (ETDEWEB)

    Policastro, A.J.; Pfingston, J.M.; Maloney, D.M.; Wasmer, F.; Pentecost, E.D.

    1992-03-01

    The Atmospheric Radiation Measurement (ARM) Program is aimed at supplying improved predictive capability of climate change, particularly the prediction of cloud-climate feedback. The objective will be achieved by measuring the atmospheric radiation and physical and meteorological quantities that control solar radiation in the earth`s atmosphere and using this information to test global climate and related models. The proposed action is to construct and operate a Cloud and Radiation Testbed (CART) research site in the southern Great Plains as part of the Department of Energy`s Atmospheric Radiation Measurement Program whose objective is to develop an improved predictive capability of global climate change. The purpose of this CART research site in southern Kansas and northern Oklahoma would be to collect meteorological and other scientific information to better characterize the processes controlling radiation transfer on a global scale. Impacts which could result from this facility are described.

  12. Radically Reducing Radiation Exposure during Routine Medical Imaging

    Science.gov (United States)

    Exposure to radiation from medical imaging in the United States has increased dramatically. NCI and several partner organizations sponsored a 2011 summit to promote efforts to reduce radiation exposure from medical imaging.

  13. Radiation-induced leiomyosarcoma of the great vessels presenting as superior vena cava syndrome

    International Nuclear Information System (INIS)

    Weiss, K.S.; Zidar, B.L.; Wang, S.

    1987-01-01

    A patient with a pleomorphic intravascular leiomyosarcoma of the great vessels of the neck and mediastinum presented clinically with a superior vena cava syndrome. A latent period of 29 years elapsed between receiving orthovoltage radiation to the neck and right side of chest to treat recurrent ganglioneuroblastoma, and the appearance of a leiomyosarcoma and subsequent recurrences. The patient underwent partial resection of the tumor, received adjunct chemotherapy, and was shown to be free of disease by clinical tests and by magnetic resonance imaging (MRI) 17 months after completion of chemotherapy. The criteria for the diagnosis of radiation-induced sarcomas are reviewed in relation to the present case. The critical role of magnetic resonance imaging in both the diagnosis and continued follow-up of the patient is described. This would appear to be the first reported case of radiation-induced intravascular leiomyosarcoma of the great vessels of the neck and mediastinum presenting as a superior vena cava syndrome

  14. Great tits (Parus major reduce caterpillar damage in commercial apple orchards.

    Directory of Open Access Journals (Sweden)

    Christel M M Mols

    Full Text Available Alternative ways to control caterpillar pests and reduce the use of pesticides in apple orchards are in the interest of the environment, farmers and the public. Great tits have already been shown to reduce damage under high caterpillar density when breeding in nest boxes in an experimental apple orchard. We tested whether this reduction also occurs under practical conditions of Integrated Pest Management (IPM, as well as Organic Farming (OF, by setting up an area with nest boxes while leaving a comparable area as a control within 12 commercial orchards. We showed that in IPM orchards, but not in OF orchards, in the areas with breeding great tits, apples had 50% of the caterpillar damage of the control areas. Offering nest boxes to attract insectivorous passerines in orchards can thus lead to more limited pesticide use, thereby adding to the natural biological diversity in an agricultural landscape, while also being economically profitable to the fruit growers.

  15. Great tits (Parus major) reduce caterpillar damage in commercial apple orchards.

    Science.gov (United States)

    Mols, Christel M M; Visser, Marcel E

    2007-02-07

    Alternative ways to control caterpillar pests and reduce the use of pesticides in apple orchards are in the interest of the environment, farmers and the public. Great tits have already been shown to reduce damage under high caterpillar density when breeding in nest boxes in an experimental apple orchard. We tested whether this reduction also occurs under practical conditions of Integrated Pest Management (IPM), as well as Organic Farming (OF), by setting up an area with nest boxes while leaving a comparable area as a control within 12 commercial orchards. We showed that in IPM orchards, but not in OF orchards, in the areas with breeding great tits, apples had 50% of the caterpillar damage of the control areas. Offering nest boxes to attract insectivorous passerines in orchards can thus lead to more limited pesticide use, thereby adding to the natural biological diversity in an agricultural landscape, while also being economically profitable to the fruit growers.

  16. A hydrogen-oxidizing, Fe(III)-reducing microorganism from the Great Bay estuary, New Hampshire

    Science.gov (United States)

    Caccavo, F.; Blakemore, R.P.; Lovley, D.R.

    1992-01-01

    A dissimilatory Fe(III)- and Mn(IV)-reducing bacterium was isolated from bottom sediments of the Great Bay estuary, New Hampshire. The isolate was a facultatively anaerobic gram-negative rod which did not appear to fit into any previously described genus. It was temporarily designated strain BrY. BrY grew anaerobically in a defined medium with hydrogen or lactate as the electron donor and Fe(III) as the electron acceptor. BrY required citrate, fumarate, or malate as a carbon source for growth on H2 and Fe(III). With Fe(III) as the sole electron acceptor, BrY metabolized hydrogen to a minimum threshold at least 60-fold lower than the threshold reported for pure cultures of sulfate reducers. This finding supports the hypothesis that when Fe(III) is available, Fe(III) reducers can outcompete sulfate reducers for electron donors. Lactate was incompletely oxidized to acetate and carbon dioxide with Fe(III) as the electron acceptor. Lactate oxidation was also coupled to the reduction of Mn(IV), U(VI), fumarate, thiosulfate, or trimethylamine n-oxide under anaerobic conditions. BrY provides a model for how enzymatic metal reduction by respiratory metal-reducing microorganisms has the potential to contribute to the mobilization of iron and trace metals and to the immobilization of uranium in sediments of Great Bay Estuary.

  17. Reducing radiation induced emesis in abdominal radiotherapy

    International Nuclear Information System (INIS)

    Griffin, K.

    1994-01-01

    In patients with seminoma testes, a comparison was made between radiation induced emesis suffered by patients receiving 'dogleg' radiotherapy with those suffered by patients who received para-aortic radiotherapy. The same comparisons were made between the effects suffered by those patients who received the anti-emetic, Ondansetron, and those suffered by patients who received conventional anti-emetics. (UK)

  18. Possible extrinsic controls on the Ordovician radiation: Stratigraphic evidence from the Great Basin, western USA

    Energy Technology Data Exchange (ETDEWEB)

    Droser, M.L. (Univ. of California, Riverside, CA (United States). Dept. of Earth Sciences); Fortey, R.A. (Natural History Museum, London (United Kingdom). Dept. of Palaeontology)

    1993-04-01

    The Ordovician radiation has been previously examined by looking at 1/analyses of patterns of diversification within small clades, 2/analyses of large databases to elucidate large-scale paleoecological patterns such as increased tiering and onshore-offshore shifts associated with this radiation. In order to resolve the relationships between these two scales of analysis there is critical need to examine in detail the paleoecology and possible biofacies shifts associated with the Ordovician radiation. The authors have examined the base of the Whiterock Series (Lower-Middle Ordovician) in the Great Basin as it represents one of the most complete records of the Ordovician radiation on the North American continent. Detailed field evidence suggests that the base of the Whiterock does not represent a simple faunal turnover but corresponds with the first occurrences in the region of groups that come to dominate the rest of the Paleozoic. Among the trilobites, this includes the lichides, calymenids, proetides, and phacopides. Similar patterns are found among the dominate Paleozoic bivalve, cephalopod, brachiopod and graptolite clades. Global correlation of this time interval suggests that this pattern of first broad geographic occurrences is not unique to North America. This boundary corresponds with a globally recognized sea level lowstand. In the Great Basin, significant facies shifts are present in shallow and deep water settings. While extrinsic controls are commonly reserved for extinctions, these data suggest that extrinsic factors may have been significant in the timing of the Paleozoic fauna rose to dominance.

  19. Great Lakes waters: radiation dose commitments, potential health effects, and cost-benefit considerations

    International Nuclear Information System (INIS)

    Ainsworth, E.J.

    1977-07-01

    In 1972, a Great Lakes Water Quality Agreement was signed by the United States and Canadian Governments. It was stipulated that the operation and effectiveness of the agreement were to be reviewed comprehensively in 1977. Aspects of the agreement concern nondegradation of Great Lakes waters and maintenance of levels of radioactivity or other potential pollutants at levels considered as low as practicable. A refined radioactivity objective of one millirem is proposed in the Water Quality Agreement. The implications of adoption of this objective are not known fully. The Division of Environmental Impact Studies was commissioned by ERDA's Division of Technology Overview to summarize the information available on the current levels of radioactivity in Great Lakes waters, compute radiation-dose commitment (integrated dose over 50 years after consumption of 2.2 liters of water of one year), and to comment on the feasibility and cost-benefit considerations associated with the refined one-millirem objective. Current levels of radioactivity in the waters of Lakes Michigan, Ontario, Erie, and Huron result in dose commitments in excess of 1 mrem for whole body and 6 mrem for bone. Future projections of isotope concentrations in Great lakes water indicate similar dose commitments for drinking water in the year 2050. Reduction of the levels of radioactivity in Great Lakes waters is not feasible, but cost-benefit considerations support removal of 226 Ra and 90 Sr through interceptive technology before water consumption. Adoption of the one-millirem objective is not propitious

  20. Research for Actively Reducing Infrared Radiation by Thermoelectric Refrigerator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hoon; Kim, Kyomin; Kim, Woochul [Yonsei Univ., Seoul (Korea, Republic of)

    2017-03-15

    We introduced a technology for reducing infrared radiation through the active cooling of hot surfaces by using a thermoelectric refrigerator. Certain surfaces were heated by aerodynamic heating, and the heat generation processes are proposed here. We calculated the temperatures and radiations from surfaces, while using thermoelectric refrigerators to cool the surfaces. The results showed that the contrast between the radiations of certain surfaces and the ambient environments can be removed using thermoelectric refrigerators.

  1. ECG movement artefacts can be greatly reduced with the aid of a movement absorbing device

    DEFF Research Database (Denmark)

    Harrison, Adrian Paul; Wandall, Kirsten; Thorball, Jørgen

    2007-01-01

    Accurate ECG signal analysis can be confounded by electric lead, and/or electrode movements varying in origin from, for example, hiccups, tremor or patient restlessness. ECG signals recorded using either a conventional electrode holder or with the aid of an electrode holder capable of absorbing...... movement artefacts, were measured on a healthy human subject. Results show a greatly improved stability of the ECG signal recorded using an electrode holder capable of absorbing movement artefacts during periods of lead disturbance, and highlight the movement artefacts that develop when the recording lead...... of a conventional ECG electrode holder is tugged or pulled during theperiod of monitoring. It is concluded that the new design of ECG electrode holder will not only enable clearer signal recordings for clinical assessment, but will reduce the ECG artefacts associated with the transportation of patients, and may...

  2. Great hammerhead sharks swim on their side to reduce transport costs.

    Science.gov (United States)

    Payne, Nicholas L; Iosilevskii, Gil; Barnett, Adam; Fischer, Chris; Graham, Rachel T; Gleiss, Adrian C; Watanabe, Yuuki Y

    2016-07-26

    Animals exhibit various physiological and behavioural strategies for minimizing travel costs. Fins of aquatic animals play key roles in efficient travel and, for sharks, the functions of dorsal and pectoral fins are considered well divided: the former assists propulsion and generates lateral hydrodynamic forces during turns and the latter generates vertical forces that offset sharks' negative buoyancy. Here we show that great hammerhead sharks drastically reconfigure the function of these structures, using an exaggerated dorsal fin to generate lift by swimming rolled on their side. Tagged wild sharks spend up to 90% of time swimming at roll angles between 50° and 75°, and hydrodynamic modelling shows that doing so reduces drag-and in turn, the cost of transport-by around 10% compared with traditional upright swimming. Employment of such a strongly selected feature for such a unique purpose raises interesting questions about evolutionary pathways to hydrodynamic adaptations, and our perception of form and function.

  3. Greatly reduced emission of greenhouse gases from the wood-processing industry

    International Nuclear Information System (INIS)

    2004-01-01

    The strong support for biomass energy in the Norwegian wood-processing industry during the last 10-15 years has contributed greatly to a considerable reduction of the emission of greenhouse gases. The potential for further reductions is primarily linked with the use of oil and involves only a few works. Oil can be replaced by other fuels, and process-technical improvements can reduce the emissions. According to prognoses, emissions will go on decreasing until 2007, when the total emission of greenhouse gases from the wood-processing industry will be about 13 per cent less than in 1998. Carbon dioxide (CO 2 ) amounts to 90 per cent of the total emission, the remaining parts being methane (CH 4 ) from landfills and dumps, and small amounts of N 2 O

  4. Distance factor on reducing scattered radiation risk during interventional fluoroscopy

    International Nuclear Information System (INIS)

    Husaini Salleh; Mohd Khalid Matori; Muhammad Jamal Mat Isa; Zainal Jamaluddin; Mohd Firdaus Abdul Rahman; Mohd Khairusalih Mohd Zin

    2012-01-01

    Interventional Radiology (IR) is subspecialty of diagnostic radiology where minimally invasive procedures are performed using an x-ray as a guidance. This procedure can deliver high radiation doses to patient and medical staff compared with other radiological method due to long screening time. The use of proper shielding, shorten the exposure time and keep the distance are the practices to reduce scattered radiation risks to staff involve in this procedure. This project is to study the distance factor on reducing the scattered radiation effect to the medical staff. It also may provide the useful information which can be use to establish the scattered radiation profile during the IR for the sake of radiation protection and safety to the medical staff involved. (author)

  5. Medical interventional procedures--reducing the radiation risks

    Energy Technology Data Exchange (ETDEWEB)

    Cousins, C. E-mail: claire.cousins@addenbrookes.nhs.uk; Sharp, C

    2004-06-01

    Over the last 40 years, the number of percutaneous interventional procedures using radiation has increased significantly, with many secondary care clinicians using fluoroscopically guided techniques. Many procedures can deliver high radiation doses to patients and staff, with the potential to cause immediate and delayed radiation effects. The challenge for interventionists is to maximize benefit, whilst minimizing radiation risk to patients and staff. Non-radiologist clinicians are often inadequately trained in radiation safety and radiobiology. However, clinical governance and legislation now requires a more rigorous approach to protecting patients and staff. Protection can be ensured, and risks can be controlled, by appropriate design, procurement and commissioning of equipment; quality assurance; and optimal operational technique, backed by audit. Interventionists need knowledge and skills to reduce the risks. Appropriate training should include awareness of the potential for radiation injury, equipment operational parameters, doses measurement and recording methods and dose reduction techniques. Clinical governance requires informed consent, appropriate patient counselling and follow-up.

  6. Medical interventional procedures--reducing the radiation risks

    International Nuclear Information System (INIS)

    Cousins, C.; Sharp, C.

    2004-01-01

    Over the last 40 years, the number of percutaneous interventional procedures using radiation has increased significantly, with many secondary care clinicians using fluoroscopically guided techniques. Many procedures can deliver high radiation doses to patients and staff, with the potential to cause immediate and delayed radiation effects. The challenge for interventionists is to maximize benefit, whilst minimizing radiation risk to patients and staff. Non-radiologist clinicians are often inadequately trained in radiation safety and radiobiology. However, clinical governance and legislation now requires a more rigorous approach to protecting patients and staff. Protection can be ensured, and risks can be controlled, by appropriate design, procurement and commissioning of equipment; quality assurance; and optimal operational technique, backed by audit. Interventionists need knowledge and skills to reduce the risks. Appropriate training should include awareness of the potential for radiation injury, equipment operational parameters, doses measurement and recording methods and dose reduction techniques. Clinical governance requires informed consent, appropriate patient counselling and follow-up

  7. Effect of radiation on activity of sulphate reducing bacteria

    International Nuclear Information System (INIS)

    Agaev, N.M.; Smorodin, A.E.; Gusejnov, M.M.

    1985-01-01

    The effect of γ-radiation on activity of sulphate reducing bacteria has been studied. Concentration of biogenic hydrogen, generated in the medium, is the main criterion, characterizing corrosion activity of the bacteria studied. The developed method of suppression of active development of sulfate reducing bacteria considerably reduces, and at lethal doses of γ-radiation eliminates altogether the bacteria activity and formation of the main corrosion agent-hydrogen sulphide-in the medium and that, in its turn, liquidates hydrogen sulphide corrosion

  8. A boundary-layer cloud study using Southern Great Plains Cloud and radiation testbed (CART) data

    Energy Technology Data Exchange (ETDEWEB)

    Albrecht, B.; Mace, G.; Dong, X.; Syrett, W. [Pennsylvania State Univ., University Park, PA (United States)] [and others

    1996-04-01

    Boundary layer clouds-stratus and fairweather cumulus - are closely coupled involves the radiative impact of the clouds on the surface energy budget and the strong dependence of cloud formation and maintenance on the turbulent fluxes of heat and moisture in the boundary layer. The continuous data collection at the Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) site provides a unique opportunity to study components of the coupling processes associated with boundary layer clouds and to provide descriptions of cloud and boundary layer structure that can be used to test parameterizations used in climate models. But before the CART data can be used for process studies and parameterization testing, it is necessary to evaluate and validate data and to develop techniques for effectively combining the data to provide meaningful descriptions of cloud and boundary layer characteristics. In this study we use measurements made during an intensive observing period we consider a case where low-level stratus were observed at the site for about 18 hours. This case is being used to examine the temporal evolution of cloud base, cloud top, cloud liquid water content, surface radiative fluxes, and boundary layer structure. A method for inferring cloud microphysics from these parameters is currently being evaluated.

  9. Reducing ionizing radiation doses during cardiac interventions in pregnant women.

    Science.gov (United States)

    Orchard, Elizabeth; Dix, Sarah; Wilson, Neil; Mackillop, Lucy; Ormerod, Oliver

    2012-09-01

    There is concern over ionizing radiation exposure in women who are pregnant or of child-bearing age. Due to the increasing prevalence of congenital and acquired heart disease, the number of women who require cardiac interventions during pregnancy has increased. We have developed protocols for cardiac interventions in pregnant women and women of child-bearing age, aimed at substantially reducing both fluoroscopy duration and radiation doses. Over five years, we performed cardiac interventions on 15 pregnant women, nine postpartum women and four as part of prepregnancy assessment. Fluoroscopy times were minimized by simultaneous use of intracardiac echocardiography, and by using very low frame rates (2/second) during fluoroscopy. The procedures most commonly undertaken were closure of atrial septal defect (ASD) or patent foramen ovale (PFO) in 16 women, coronary angiograms in seven, right and left heart catheters in three and two stent placements. The mean screening time for all patients was 2.38 minutes (range 0.48-13.7), the median radiation dose was 66 (8.9-1501) Gy/cm(2). The median radiation dose to uterus was 1.92 (0.59-5.47) μGy, and the patient estimated dose was 0.24 (0.095-0.80) mSv. Ionizing radiation can be used safely in the management of severe cardiac structural disease in pregnancy, with very low ionizing radiation dose to the mother and extremely low exposure to the fetus. With experience, ionizing radiation doses at our institution have been reduced.

  10. Effect of the Great Attractor on the cosmic microwave background radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bertschinger, E [Massachusetts Inst. of Tech., Cambridge, MA (USA). Dept. of Physics; Gorski, K M [Los Alamos National Lab., NM (USA); Dekel, A [Hebrew Univ., Jerusalem (Israel). Racah Inst. of Physics

    1990-06-07

    ANISOTROPY in the cosmic microwave background radiation (CMB) is expected as a result of fluctuations in gravitational potential caused by large-scale structure in the Universe. The background radiation is redshifted as it climbs out of gravitational wells. Here we present a map of the anisotropy in CMB temperature {Delta}T/T of our region of the Universe as viewed by a distant observer, predicted on the basis of the gravitational potential field. We calculate this field in the vicinity of the Local Group of galaxies from the observed peculiar (non-Hubble) velocities of galaxies, under the assumption that the peculiar motions are induced by gravity. If the cosmological density parameter {Omega} is 1, the gravitational potential field of the Great Attractor and surrounding regions produces a maximum Sachs-Wolfe anisotropy of {Delta}T/T=(1.7{plus minus}0.3) x 10{sup -5} on an angular scale of 1deg. Doppler and adiabatic contributions to this anisotropy are expected to be somewhat larger. If similar fluctuations in the gravitational potential are present elsewhere in the Universe, the anisotropy present when the CMB was last scattered should be visible from the Earth, and should be detectable in current experiments. A fundamental test of whether gravity is responsible for the generation of structure in the Universe can be made by looking for the imprint in the CMB of deep potential wells similar to those found in our neighbourhood, (author).

  11. Spatial variation of natural radiation and childhood leukaemia incidence in Great Britain

    International Nuclear Information System (INIS)

    Richardson, Sylvia; Monfort, Christine; Green, Martyn; Muirhead, Colin; Draper, Gerald

    1995-01-01

    This paper describes an analysis of the geographical variation of childhood leukaemia incidence in Great Britain over a 15 year period in relation to natural radiation (gamma and radon). Data at the level of the 459 district level local authorities in England, Wales and regional districts in Scotland are analysed in two complementary ways: first, by Poisson regressions with the inclusion of environmental covariates and a smooth spatial structure; secondly, by a hierarchical Bayesian model in which extra-Poisson variability is modelled explicitly in terms of spatial and non-spatial components. From this analysis, we deduce a strong indication that a main part of the variability is accounted for by a local neighbourhood 'clustering' structure. This structure is furthermore relatively stable over the 15 year period for the lymphocytic leukaemias which make up the majority of observed cases. We found no evidence of a positive association of childhood leukaemia incidence with outdoor or indoor gamma radiation levels. There is no consistent evidence of any association with radon levels. Indeed, in the Poisson regressions, a significant positive association was only observed for one 5-year period, a result which is not compatible with a stable environmental effect. Moreover, this positive association became clearly non-significant when over-dispersion relative to the Poisson distribution was taken into account. (author)

  12. The development of occupational, public and environmental radiation protection legislation in Great Britain

    International Nuclear Information System (INIS)

    Bines, W.P.; Chandler, S.D.

    2000-01-01

    In Great Britain, legislation to protect workers exposed to ionising radiation has developed separately from, but largely in parallel with, legislation to protect the public and the environment. Occupational radiation protection started from a narrow and industry specific base in 1947. Over the succeeding years, and partly in response to the obligations arising from the United Kingdom's accession to the European Community, this narrow base has broadened. As the nuclear power industry developed in Great Britain so did a separate and rigorous regulatory regime for nuclear installations, starting with the Nuclear Installations (Licensing and Insurance) Act 1959. The 1959 Act was amended by the Nuclear Installations Act 1965. From 1974, all occupational health and safety legislation began to be brought under the umbrella of a new legal framework, the Health and Safety at Work etc. Act, which for the first time adopted an across-the board approach to all work activities and goal-setting, rather than prescriptive, legislation. The purpose of the Act was to provide one comprehensive and integrated system of law concerning health and safety (including the self-employed) and also public safety, so far as it was affected by work activities. The Act also provided for consultation with all interested parties during the development of legislation. The first across the board occupational radiation protection legislation, covering all uses and users of ionising radiation (including, for the first time, exposure to natural radiation), arrived with the Ionising Radiations Regulations 1985 and supporting Approved Codes of Practice and non-statutory guidance. The need for some controls on the use of radioactive materials that went wider than simply the protection of workers was recognised in 1948, when the first Radioactive Substances Act was made. Although the 1948 Act was the first to mention radioactive waste specifically, it proved ineffective as a regulatory tool. The first

  13. Monitoring and forecasting of great radiation hazards for spacecraft and aircrafts by online cosmic ray data

    Science.gov (United States)

    Dorman, L. I.

    2005-11-01

    We show that an exact forecast of great radiation hazard in space, in the magnetosphere, in the atmosphere and on the ground can be made by using high-energy particles (few GeV/nucleon and higher) whose transportation from the Sun is characterized by a much bigger diffusion coefficient than for small and middle energy particles. Therefore, high energy particles come from the Sun much earlier (8-20 min after acceleration and escaping into solar wind) than the main part of smaller energy particles (more than 30-60 min later), causing radiation hazard for electronics and personal health, as well as spacecraft and aircrafts. We describe here principles of an automatic set of programs that begin with "FEP-Search", used to determine the beginning of a large FEP event. After a positive signal from "FEP-Search", the following programs start working: "FEP-Research/Spectrum", and then "FEP-Research/Time of Ejection", "FEP-Research /Source" and "FEP-Research/Diffusion", which online determine properties of FEP generation and propagation. On the basis of the obtained information, the next set of programs immediately start to work: "FEP-Forecasting/Spacecrafts", "FEP-Forecasting/Aircrafts", "FEP-Forecasting/Ground", which determine the expected differential and integral fluxes and total fluency for spacecraft on different orbits, aircrafts on different airlines, and on the ground, depending on altitude and cutoff rigidity. If the level of radiation hazard is expected to be dangerous for high level technology or/and personal health, the following programs will be used "FEP-Alert/Spacecrafts", "FEP-Alert/ Aircrafts", "FEP-Alert/Ground".

  14. Monitoring and forecasting of great radiation hazards for spacecraft and aircrafts by online cosmic ray data

    Directory of Open Access Journals (Sweden)

    L. I. Dorman

    2005-11-01

    Full Text Available We show that an exact forecast of great radiation hazard in space, in the magnetosphere, in the atmosphere and on the ground can be made by using high-energy particles (few GeV/nucleon and higher whose transportation from the Sun is characterized by a much bigger diffusion coefficient than for small and middle energy particles. Therefore, high energy particles come from the Sun much earlier (8-20 min after acceleration and escaping into solar wind than the main part of smaller energy particles (more than 30-60 min later, causing radiation hazard for electronics and personal health, as well as spacecraft and aircrafts. We describe here principles of an automatic set of programs that begin with "FEP-Search", used to determine the beginning of a large FEP event. After a positive signal from "FEP-Search", the following programs start working: "FEP-Research/Spectrum", and then "FEP-Research/Time of Ejection", "FEP-Research /Source" and "FEP-Research/Diffusion", which online determine properties of FEP generation and propagation. On the basis of the obtained information, the next set of programs immediately start to work: "FEP-Forecasting/Spacecrafts", "FEP-Forecasting/Aircrafts", "FEP-Forecasting/Ground", which determine the expected differential and integral fluxes and total fluency for spacecraft on different orbits, aircrafts on different airlines, and on the ground, depending on altitude and cutoff rigidity. If the level of radiation hazard is expected to be dangerous for high level technology or/and personal health, the following programs will be used "FEP-Alert/Spacecrafts", "FEP-Alert/ Aircrafts", "FEP-Alert/Ground".

  15. Numerical Study on Similarity of Plume’s Infrared Radiation from Reduced Scaling Solid Rocket

    Directory of Open Access Journals (Sweden)

    Xiaoying Zhang

    2015-01-01

    Full Text Available Similarity of plume radiation between reduced scaling solid rocket models and full scale ones in ground conditions has been taken for investigation. Flow and radiation of plume from solid rockets with scaling ratio from 0.1 to 1 have been computed. The radiative transfer equation (RTE is solved by the finite volume method (FVM in infrared band 2~6 μm. The spectral characteristics of plume gases have been calculated with the weighted-sum-of-gray-gas (WSGG model, and those of the Al2O3 particles have been solved by the Mie scattering model. Our research shows that, with the decreasing scaling ratio of the rocket engine, the radiation intensity of the plume decreases with 1.5~2.5 power of the scaling ratio. The infrared radiation of the plume gases shows a strong spectral dependency, while that of the Al2O3 particles shows grey property. Spectral radiation intensity of the high temperature core of the solid rocket plume increases greatly in the peak absorption spectrum of plume gases. Al2O3 particle is the major radiation composition in the rocket plume, whose scattering coefficient is much larger than its absorption coefficient. There is good similarity between spectral variations of plumes from different scaling solid rockets. The directional plume radiation rises with the increasing azimuth angle.

  16. Improvement of NSSS design to reduce occupational radiation exposure (ORE)

    International Nuclear Information System (INIS)

    Dubourg, M.

    1985-05-01

    As a result of its R and D activities, FRAMATOME has initiated concrete measures to help to reduce personnel radiation exposure. These measures include reduction in the sources and quantity of activable products, and in the duration of personnel exposure during maintenance

  17. Evaluating shielding effectiveness for reducing space radiation cancer risks

    International Nuclear Information System (INIS)

    Cucinotta, Francis A.; Kim, Myung-Hee Y.; Ren, Lei

    2006-01-01

    We discuss calculations of probability distribution functions (PDF) representing uncertainties in projecting fatal cancer risk from galactic cosmic rays (GCR) and solar particle events (SPE). The PDFs are used in significance tests for evaluating the effectiveness of potential radiation shielding approaches. Uncertainties in risk coefficients determined from epidemiology data, dose and dose-rate reduction factors, quality factors, and physics models of radiation environments are considered in models of cancer risk PDFs. Competing mortality risks and functional correlations in radiation quality factor uncertainties are included in the calculations. We show that the cancer risk uncertainty, defined as the ratio of the upper value of 95% confidence interval (CI) to the point estimate is about 4-fold for lunar and Mars mission risk projections. For short-stay lunar missions ( 180d) or Mars missions, GCR risks may exceed radiation risk limits that are based on acceptable levels of risk. For example, the upper 95% CI exceeding 10% fatal risk for males and females on a Mars mission. For reducing GCR cancer risks, shielding materials are marginally effective because of the penetrating nature of GCR and secondary radiation produced in tissue by relativistic particles. At the present time, polyethylene or carbon composite shielding cannot be shown to significantly reduce risk compared to aluminum shielding based on a significance test that accounts for radiobiology uncertainties in GCR risk projection

  18. Reducing radiation exposure in newborns with birth head trauma

    Directory of Open Access Journals (Sweden)

    Irina A. Kriukova

    2017-12-01

    Full Text Available Background. Birth head trauma causing intracranial injury is one of the most common causes of neonatal mortality and morbidity. In case of suspected cranial fractures and intracranial hematomas, diagnostic methods involving radiation, such as x-ray radiography and computed tomography, are recommended. Recently, an increasing number of studies have highlighted the risk of cancer complications associated with computed tomography in infants. Therefore, diagnostic methods that reduce radiation exposure in neonates are important. One such method is ultrasonography (US. Aim. We evaluated US as a non-ionizing radiation method for diagnosis of cranial bone fractures and epidural hematomas in newborns with cephalohematomas or other birth head traumas. Material and methods. The study group included 449 newborns with the most common variant of birth head trauma: cephalohematomas. All newborns underwent transcranial-transfontanelle US for detection of intracranial changes and cranial US for visualization of bone structure in the cephalohematoma region. Children with ultrasonic signs of cranial fractures and epidural hematomas were further examined at a children’s hospital by x-ray radiography and/or computed tomography. Results and discussion. We found that cranial US for diagnosis of cranial fractures and transcranial-transfontanelle US for diagnosis of epidural hematomas in newborns were highly effective. In newborns with parietal cephalohematomas (444 children, 17 (3.8% had US signs of linear fracture of the parietal bone, and 5 (1.1% had signs of ipsilateral epidural hematoma. Epidural hematomas were visualized only when US was performed through the temporal bone and not by using the transfontanelle approach. Sixteen cases of linear fractures and all epidural hematomas were confirmed by computed tomography. Conclusion. The use of US diagnostic methods reduced radiation exposure in newborns with birth head trauma. US methods (transcranial

  19. Initiatives to reduce the occupational radiation exposure of ABWR plants

    International Nuclear Information System (INIS)

    Hirasawa, Hajime; Urata, Hidehiro; Ueda, Taku; Yamamoto, Seiji; Yaita, Yumi

    2014-01-01

    Toshiba has carried out radiation exposure reduction by radiation level reduction, as reduction of reactor water activated corrosion products concentration, reduction of activated corrosion products deposition and radiation shielding, and exposure time reduction, as remote control and improvement of maintenance work procedures. Water chemistry has been mainly carried out reduction of reactor water activated corrosion products concentration and reduction of activated corrosion products deposition in radiation level reduction. The reduction measures of reactor water activated corrosion products concentration are mainly reduction of iron crud concentration and reduction of cobalt ion concentration. The activated corrosion products deposition are reduced by the means of water quality control and the surface treatment. Water quality control for reduction of activated corrosion products deposition moves to ultra low iron high nickel control from Ni/Fe ratio control. The surface treatments are adopted to the stainless steel piping and carbon steel piping. As a measure further to radiation exposure reduction for ABWR (Advanced Boiling Water Reactors), we report on the effect of generation amount reduction by the adoption of alternate material and the effect of deposition reduction by material change of piping and the adoption of advanced water quality control, etc. (author)

  20. Reducing waste generation and radiation exposure by analytical method modification

    International Nuclear Information System (INIS)

    Ekechukwu, A.A.

    1996-01-01

    The primary goal of an analytical support laboratory has traditionally been to provide accurate data in a timely and cost effective fashion. Added to this goal is now the need to provide the same high quality data while generating as little waste as possible. At the Savannah River Technology Center (SRTC), we have modified and reengineered several methods to decrease generated waste and hence reduce radiation exposure. These method changes involved improving detection limits (which decreased the amount of sample required for analysis), decreasing reaction and analysis time, decreasing the size of experimental set-ups, recycling spent solvent and reagents, and replacing some methods. These changes had the additional benefits of reducing employee radiation exposure and exposure to hazardous chemicals. In all cases, the precision, accuracy, and detection limits were equal to or better than the replaced method. Most of the changes required little or no expenditure of funds. This paper describes these changes and discusses some of their applications

  1. CAUSES: Attribution of Surface Radiation Biases in NWP and Climate Models near the U.S. Southern Great Plains

    Science.gov (United States)

    Van Weverberg, K.; Morcrette, C. J.; Petch, J.; Klein, S. A.; Ma, H.-Y.; Zhang, C.; Xie, S.; Tang, Q.; Gustafson, W. I.; Qian, Y.; Berg, L. K.; Liu, Y.; Huang, M.; Ahlgrimm, M.; Forbes, R.; Bazile, E.; Roehrig, R.; Cole, J.; Merryfield, W.; Lee, W.-S.; Cheruy, F.; Mellul, L.; Wang, Y.-C.; Johnson, K.; Thieman, M. M.

    2018-04-01

    Many Numerical Weather Prediction (NWP) and climate models exhibit too warm lower tropospheres near the midlatitude continents. The warm bias has been shown to coincide with important surface radiation biases that likely play a critical role in the inception or the growth of the warm bias. This paper presents an attribution study on the net radiation biases in nine model simulations, performed in the framework of the CAUSES project (Clouds Above the United States and Errors at the Surface). Contributions from deficiencies in the surface properties, clouds, water vapor, and aerosols are quantified, using an array of radiation measurement stations near the Atmospheric Radiation Measurement Southern Great Plains site. Furthermore, an in-depth analysis is shown to attribute the radiation errors to specific cloud regimes. The net surface shortwave radiation is overestimated in all models throughout most of the simulation period. Cloud errors are shown to contribute most to this overestimation, although nonnegligible contributions from the surface albedo exist in most models. Missing deep cloud events and/or simulating deep clouds with too weak cloud radiative effects dominate in the cloud-related radiation errors. Some models have compensating errors between excessive occurrence of deep cloud but largely underestimating their radiative effect, while other models miss deep cloud events altogether. Surprisingly, even the latter models tend to produce too much and too frequent afternoon surface precipitation. This suggests that rather than issues with the triggering of deep convection, cloud radiative deficiencies are related to too weak convective cloud detrainment and too large precipitation efficiencies.

  2. Strategies to reduce radiation dose in cardiac PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tung Hsin; Wu, Nien-Yun [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan (China); Wang, Shyh-Jen [Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan (China); Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Wu, Jay [Institute of Radiological science, Central Taiwan University of Science and Technology, Taichung, Taiwan (China); Mok, Greta S.P. [Department of Electrical and Electronics Engineering, Faculty of Science and Technology, University of Macau, Macau (China); Yang, Ching-Ching, E-mail: g39220003@yahoo.com.tw [Department of Radiological Technology, Tzu Chi College of Technology, 880, Sec.2, Chien-kuo Rd. Hualien 970, Taiwan (China); Huang, Tzung-Chi, E-mail: tzungchi.huang@mail.cmu.edu.tw [Department of Biomedical Imaging and Radiological Science, China Medical University, No.91 Hsueh-Shih Road, Taichung 40402, Taiwan (China)

    2011-08-21

    Background: Our aim was to investigate CT dose reduction strategies on a hybrid PET/CT scanner for cardiac applications. Materials: Image quality and dose estimation of different CT scanning protocols for CT coronary angiography (CTCA), and CT-based attenuation correction for PET imaging were investigated. Fifteen patients underwent CTCA, perfusion PET imaging at rest and under stress, and FDG PET for myocardial viability. These patients were divided into three groups based on the CTCA technique performed: retrospectively gated helical (RGH), ECG tube current modulation (ETCM), and prospective gated axial (PGA) acquisitions. All emission images were corrected for photon attenuation using CT images obtained by default setting and an ultra-low dose CT (ULDCT) scan. Results: Radiation dose in RGH technique was 22.2{+-}4.0 mSv. It was reduced to 10.95{+-}0.82 and 4.13{+-}0.31 mSv using ETCM and PGA techniques, respectively. Radiation dose in CT transmission scan was reduced by 96.5% (from 4.53{+-}0.5 to 0.16{+-}0.01 mSv) when applying ULDCT as compared to the default CT. No significant difference in terms of image quality was found among various protocols. Conclusion: The proposed CT scanning strategies, i.e. ETCM or PGA for CTCA and ULDCT for PET attenuation correction, could reduce radiation dose up to 47% without degrading imaging quality in an integrated cardiac PET/CT coronary artery examination.

  3. Zinc injection helps reduce radiation field buildup in BWRs

    International Nuclear Information System (INIS)

    Wood, C.

    1991-01-01

    The injection of zinc into the reactor water of BWRs (Boiling Water Reactors) was a technique developed by General Electric (GE) and the Electric Power Research Institute (EPRI) to control the buildup of radiation fields from cobalt-60 on out-of-core piping. The presence of 5-10ppb zinc in the reactor water reduces the growth of oxide films on stainless steel surfaces, thereby reducing the number of sites available for the incorporation of cobalt; zinc also competes with cobalt for the sites. In September 1990, EPRI organized a workshop at the request of several US utilities to provide a forum to discuss experiences with zinc injection. The meeting focused on six main issues: the effect of zinc on radiation fields in normal water chemistry; the radiation buildup in hydrogen water chemistry, with and without zinc; the effects of zinc-65; the corrosion of fuel cladding and structural materials; the performance of zinc injection and monitoring equipment; and planning for zinc injection. (author)

  4. A novel radiation protection drape reduces radiation exposure during fluoroscopy guided electrophysiology procedures.

    Science.gov (United States)

    Germano, Joseph J; Day, Gina; Gregorious, David; Natarajan, Venkataraman; Cohen, Todd

    2005-09-01

    The purpose of this study was to evaluate a novel disposable lead-free radiation protection drape for decreasing radiation scatter during electrophysiology procedures. In recent years, there has been an exponential increase in the number of electrophysiology (EP) procedures exposing patients, operators and laboratory staff to higher radiation doses. The RADPAD was positioned slightly lateral to the incision site for pectoral device implants and superior to the femoral vein during electrophysiology studies. Each patient served as their own control and dosimetric measurements were obtained at the examiner's elbow and hand. Radiation badge readings for the operator were obtained three months prior to RADPAD use and three months after introduction. Radiation dosimetry was obtained in twenty patients: 7 electrophysiology studies, 6 pacemakers, 5 catheter ablations, and 2 implantable cardioverter-defibrillators. Eleven women and nine men with a mean age of 63 +/- 4 years had an average fluoroscopy time of 2.5 +/- 0.42 minutes per case. Mean dosimetric measurements at the hand were reduced from 141.38 +/- 24.67 to 48.63 +/- 9.02 milliroentgen (mR) per hour using the protective drape (63% reduction; p < 0.0001). Measurements at the elbow were reduced from 78.78 +/- 7.95 mR per hour to 34.50 +/- 4.18 mR per hour using the drape (55% reduction; p < 0.0001). Badge readings for three months prior to drape introduction averaged 2.45 mR per procedure versus 1.54 mR per procedure for 3 months post-initiation (37% reduction). The use of a novel radiation protection surgical drape can significantly reduce scatter radiation exposure to staff and operators during a variety of EP procedures.

  5. The impact of reducing car weight on global emissions: the future fleet in Great Britain

    Science.gov (United States)

    Serrenho, André Cabrera; Norman, Jonathan B.; Allwood, Julian M.

    2017-05-01

    Current European policies define targets for future direct emissions of new car sales that foster a fast transition to electric drivetrain technologies. However, these targets do not consider the emissions produced in electricity generation and material production, and therefore fail to incentivise car manufacturers to consider the benefits of vehicle weight reduction. In this paper, we examine the potential benefits of limiting the average weight and altering the material composition of new cars in terms of global greenhouse gas emissions produced during the use phase, electricity generation and material production. We anticipate the emissions savings for the future car fleet in Great Britain until 2050 for various alternative futures, using a dynamic material flow analysis of ferrous metals and aluminium, and considering an evolving demand for car use. The results suggest that fostering vehicle weight reduction could produce greater cumulative emissions savings by 2050 than those obtained by incentivising a fast transition to electric drivetrains, unless there is an extreme decarbonization of the electricity grid. Savings promoted by weight reduction are immediate and do not depend on the pace of decarbonization of the electricity grid. Weight reduction may produce the greatest savings when mild steel in the car body is replaced with high-strength steel. This article is part of the themed issue 'Material demand reduction'.

  6. Direct coronary stenting in reducing radiation and radiocontrast consumption

    International Nuclear Information System (INIS)

    Caluk, Jasmin; Osmanovic, Enes; Barakovic, Fahir; Kusljugic, Zumreta; Terzic, Ibrahim; Caluk, Selma; Sofic, Amela

    2010-01-01

    Coronary stenting is the primary means of coronary revascularization. There are two basic techniques of stent implantation: stenting with balloon predilatation of stenosis and stenting without predilatation (direct stenting). Limiting the time that a fluoroscope is activated and by appropriately managing the intensity of the applied radiation, the operator limits radiation in the environment, and this saves the exposure to the patient and all personnel in the room. Nephrotoxicity is one of the most important properties of radiocontrast. The smaller amount of radiocontrast used also provides multiple positive effects, primarily regarding the periprocedural risk for the patients with the reduced renal function. The goal of the study was to compare fluoroscopy time, the amount of radiocontrast, and expenses of material used in direct stenting and in stenting with predilatation. In a prospective study, 70 patients with coronary disease were randomized to direct stenting, or stenting with predilatation. Fluoroscopy time and radiocontrast use were significantly reduced in the directly stented patients in comparison to the patients stented with balloon-predilatation. The study showed a significant reduction of expenses when using a direct stenting method in comparison to stenting with predilatation. If the operator predicts that the procedure can be performed using direct stenting, he is encouraged to do so. Direct stenting is recommended for all percutaneous coronary interventions when appropriate conditions have been met. If direct stenting has been unsuccessful, the procedure can be converted to predilatation

  7. Gallium ion implantation greatly reduces thermal conductivity and enhances electronic one of ZnO nanowires

    Directory of Open Access Journals (Sweden)

    Minggang Xia

    2014-05-01

    Full Text Available The electrical and thermal conductivities are measured for individual zinc oxide (ZnO nanowires with and without gallium ion (Ga+ implantation at room temperature. Our results show that Ga+ implantation enhances electrical conductivity by one order of magnitude from 1.01 × 103 Ω−1m−1 to 1.46 × 104 Ω−1m−1 and reduces its thermal conductivity by one order of magnitude from 12.7 Wm−1K−1 to 1.22 Wm−1K−1 for ZnO nanowires of 100 nm in diameter. The measured thermal conductivities are in good agreement with those in theoretical simulation. The increase of electrical conductivity origins in electron donor doping by Ga+ implantation and the decrease of thermal conductivity is due to the longitudinal and transverse acoustic phonons scattering by Ga+ point scattering. For pristine ZnO nanowires, the thermal conductivity decreases only two times when its diameter reduces from 100 nm to 46 nm. Therefore, Ga+-implantation may be a more effective method than diameter reduction in improving thermoelectric performance.

  8. Artificial Light at Night Reduces Daily Energy Expenditure in Breeding Great Tits (Parus major

    Directory of Open Access Journals (Sweden)

    Anouk A. M. H. Welbers

    2017-05-01

    Full Text Available The ecological impact of artificial light at night (ALAN is an increasingly recognized process that accompanies expanding urbanization. Yet, we have limited knowledge on the impact of ALAN on wild species, and on the potential to mitigate any negative effects by using different light sources and colors. In birds, effects of ALAN on activity levels are reported for several species and, hence, their daily energy expenditure (DEE may be affected. DEE is a potent mediator of life-history trade-offs and fitness and thus an important aspect to consider when examining the potential long-term ecological effects of ALAN. Previous work has suggested that birds exposed to ALAN show higher levels of provisioning and nocturnal activity, suggesting that white ALAN increases DEE. Other factors regulating DEE, such as provisioning behavior and food availability, might also respond to ALAN and thus indirectly affect DEE. We tested the hypothesis that ALAN increases DEE using an experimental setup where four previously unlit transects were illuminated with either white, green, or red LED light, or left dark as a control treatment. This setup was replicated in eight locations across the Netherlands. We measured DEE of our focal species, the great tit (Parus major, using a novel doubly labeled water technique that uses breath rather than blood samples. Contrary to our expectations, birds feeding their offspring under white and green ALAN showed lower DEE compared to birds in the control dark treatment. Differences in chick provisioning activity did not explain this result, as neither visit rates nor daily activity timing was affected by light treatment. However, food availability under white and green light was much higher compared to red light and the dark control. This difference strongly suggests that the lower DEE under white and green ALAN sites is a consequence of higher food availability in these treatments. This result shows that there can be positive

  9. Environmental radiation level, radiation anxiety, and psychological distress of non-evacuee residents in Fukushima five years after the Great East Japan Earthquake: Multilevel analyses

    Directory of Open Access Journals (Sweden)

    Maiko Fukasawa

    2017-12-01

    Full Text Available The present study aimed to clarify the associations among radiation exposure or psychological exposure to the Fukushima nuclear power plant accident (i.e., fear/anxiety immediately after the accident, current radiation anxiety, and psychological distress among non-evacuee community residents in Fukushima five years after the Great East Japan Earthquake, which occurred in March 2011. A questionnaire survey was administered to a random sample of non-evacuee community residents from 49 municipalities of Fukushima prefecture from February to April 2016, and data from 1684 respondents (34.4% were analyzed. Environmental radiation levels at the time of the accident were ascertained from survey meter data, while environmental radiation levels at the time of the survey were ascertained from monitoring post data. In the questionnaire, immediate fear/anxiety after the accident, current radiation anxiety, and psychological distress were measured using a single-item question, a 7-item scale, and K6, respectively. Multilevel linear or logistic regression models were applied to analyze the determinants of radiation anxiety and psychological distress. The findings showed that environmental radiation levels at the time of the survey were more strongly associated with radiation anxiety than radiation levels immediately after the accident. Disaster-related experiences, such as direct damage, disaster-related family stress, and fear/anxiety after the accident, and demographic characteristics (e.g., younger age, being married, low socioeconomic status were significantly associated with radiation anxiety. Environmental radiation levels at the time of the accident or survey were not significantly associated with psychological distress. Radiation anxiety largely mediated the association between fear/anxiety after the accident and psychological distress. In addition to environmental radiation levels, respondents’ radiation anxiety was affected by multiple factors

  10. Genetic Correlations Greatly Increase Mutational Robustness and Can Both Reduce and Enhance Evolvability.

    Directory of Open Access Journals (Sweden)

    Sam F Greenbury

    2016-03-01

    Full Text Available Mutational neighbourhoods in genotype-phenotype (GP maps are widely believed to be more likely to share characteristics than expected from random chance. Such genetic correlations should strongly influence evolutionary dynamics. We explore and quantify these intuitions by comparing three GP maps-a model for RNA secondary structure, the HP model for protein tertiary structure, and the Polyomino model for protein quaternary structure-to a simple random null model that maintains the number of genotypes mapping to each phenotype, but assigns genotypes randomly. The mutational neighbourhood of a genotype in these GP maps is much more likely to contain genotypes mapping to the same phenotype than in the random null model. Such neutral correlations can be quantified by the robustness to mutations, which can be many orders of magnitude larger than that of the null model, and crucially, above the critical threshold for the formation of large neutral networks of mutationally connected genotypes which enhance the capacity for the exploration of phenotypic novelty. Thus neutral correlations increase evolvability. We also study non-neutral correlations: Compared to the null model, i If a particular (non-neutral phenotype is found once in the 1-mutation neighbourhood of a genotype, then the chance of finding that phenotype multiple times in this neighbourhood is larger than expected; ii If two genotypes are connected by a single neutral mutation, then their respective non-neutral 1-mutation neighbourhoods are more likely to be similar; iii If a genotype maps to a folding or self-assembling phenotype, then its non-neutral neighbours are less likely to be a potentially deleterious non-folding or non-assembling phenotype. Non-neutral correlations of type i and ii reduce the rate at which new phenotypes can be found by neutral exploration, and so may diminish evolvability, while non-neutral correlations of type iii may instead facilitate evolutionary exploration

  11. Genetic Correlations Greatly Increase Mutational Robustness and Can Both Reduce and Enhance Evolvability

    Science.gov (United States)

    Greenbury, Sam F.; Schaper, Steffen; Ahnert, Sebastian E.; Louis, Ard A.

    2016-01-01

    Mutational neighbourhoods in genotype-phenotype (GP) maps are widely believed to be more likely to share characteristics than expected from random chance. Such genetic correlations should strongly influence evolutionary dynamics. We explore and quantify these intuitions by comparing three GP maps—a model for RNA secondary structure, the HP model for protein tertiary structure, and the Polyomino model for protein quaternary structure—to a simple random null model that maintains the number of genotypes mapping to each phenotype, but assigns genotypes randomly. The mutational neighbourhood of a genotype in these GP maps is much more likely to contain genotypes mapping to the same phenotype than in the random null model. Such neutral correlations can be quantified by the robustness to mutations, which can be many orders of magnitude larger than that of the null model, and crucially, above the critical threshold for the formation of large neutral networks of mutationally connected genotypes which enhance the capacity for the exploration of phenotypic novelty. Thus neutral correlations increase evolvability. We also study non-neutral correlations: Compared to the null model, i) If a particular (non-neutral) phenotype is found once in the 1-mutation neighbourhood of a genotype, then the chance of finding that phenotype multiple times in this neighbourhood is larger than expected; ii) If two genotypes are connected by a single neutral mutation, then their respective non-neutral 1-mutation neighbourhoods are more likely to be similar; iii) If a genotype maps to a folding or self-assembling phenotype, then its non-neutral neighbours are less likely to be a potentially deleterious non-folding or non-assembling phenotype. Non-neutral correlations of type i) and ii) reduce the rate at which new phenotypes can be found by neutral exploration, and so may diminish evolvability, while non-neutral correlations of type iii) may instead facilitate evolutionary exploration and so

  12. Rotating machinery surveillance system reduces plant downtime and radiation exposure

    International Nuclear Information System (INIS)

    Bohanick, J.S.; Robinson, J.C.; Allen, J.W.

    1988-01-01

    A rotating machinery surveillance system (RMSS) was permanently installed at Grand Gulf nuclear station (GGNS) as part of a program sponsored by the US Department of Energy whose goal was to reduce radiation exposure to power plant personnel resulting from the inspection, maintenance, and repair of rotating machinery. The RMSS was installed at GGNS in 1983 to continuously monitor 173 analog vibration signals from proximity probes mounted on 26 machine trains and ∼450 process data points via a computer data link. Vibration frequency spectra, i.e., the vibration amplitude versus frequency of vibration, and various characterizations of these spectra are the fundamental data collected by the RMSS for performing machinery diagnostics. The RMSS collects vibration frequency spectra on a daily basis for all the monitored rotating equipment and automatically stores the collected spectra for review by the vibration engineer. Vibration spectra automatically stored by the RMSS fall into categories that include the last normal, alarm, minimum and maximum, past three-day data set, baseline, current, and user-saved spectra. During first and second fuel-cycle operation at GGNS, several significant vibration problems were detected by the RMSS. Two of these are presented in this paper: recirculation pumps and turbine-generator bearing degradation. The total reduction in personnel radiation exposure at GGNS from 1985 to 1987 due to the presence of the RMSS was estimated to be in the range from 49 to 54 person-rem

  13. Reducing radiation exposure during oral I-131 therapy administration

    International Nuclear Information System (INIS)

    Trujillo, J.; Krinsky, S.; Wilson, B.; Teague, E.

    1982-01-01

    A new, closed-system method to reduce air-, direct-, and incidental-contamination during therapeutic administration of oral I-131 was experimentally evaluated on twelve patients. We studied a standard control population using the routine practice of drinking the solution through a straw and compared results with our new technique. Various measurements were performed throughout all phases of dose administration to assess the relative difference of the two approaches. Using the closed system method before and during iodine administration revealed between 100 and 1000 times less activity per millimeter of air sample; whereas, the direct radiation exposure values were higher for the control population. Both the experimental and control methods had similar levels of incidental contamination

  14. A comparison of radiometric fluxes influenced by parameterization cirrus clouds with observed fluxes at the Southern Great Plains (SGP) cloud and radiation testbed (CART) site

    Energy Technology Data Exchange (ETDEWEB)

    Mace, G.G.; Ackerman, T.P.; George, A.T. [Penn State Univ., University Park, PA (United States)

    1996-04-01

    The data from the Atmospheric Radiation Measurement (ARM) Program`s Southern Great plains Site (SCP) is a valuable resource. We have developed an operational data processing and analysis methodology that allows us to examine continuously the influence of clouds on the radiation field and to test new and existing cloud and radiation parameterizations.

  15. The great east Japan earthquake and radiation exposure problem in Fukushima

    International Nuclear Information System (INIS)

    Otani, Koji; Konno, Shinichi; Shishido, Hiroaki

    2012-01-01

    Described are actions taken by Fukushima Medical University (FMU) and its Department of Orthopedic Surgery (DOS) after the Quake Disaster (Mar. 11, 2011), and present state, at about 1 year later, of Fukushima Prefecture suffering from the Fukushima Daiichi Power Plant (FDPP) radiation problem. Firstly described are the roles played by FMU as a backup medical supporting facility and by DOS therein according to the following time frame. During several days after the Quake, 35 DMAT (Disaster Medical Assistant Team) consisting from 180 professionals gathered in FMU. The number of emergent outpatients within 3 days after the quake was 168, and 10 patients involving 4 with trauma underwent 11 operations by DOS. Within the next 1 week after, FMU tentatively received 175 patients transported from evacuation area localizing at 30 km distance from FDPP. At later than 2 weeks after, FMU re-started the routine medicare of outpatients in its all departments (Mar. 28), when high grade DMAT and local family medicare team started to visit refuges and isolated patients, respectively. Numbers of patients with the disaster-related trauma needed for hospitalization in 3 DOS related facilities having >1,000 beds in the Prefecture were 18-38, 10-25, 5-9 and 3-8, in the order of respective months from March to June. Second, FMU activities against radiation exposure started with visit of 4 possibly exposed residents on Mar. 12, with voluntary cooperation of many medical students. Medical training held in Sep. 2010 was quite useful for the rapid action of FMU to the Disaster, which made personnel recognize the importance of such education. Problems of external and internal exposure of low dose radiation are the future task, for which follow-up of health survey of 2,020 thousands Prefectural residents is to be continued for >30 years onward. At present, restoration of medicare seems difficult to recover to the level before the Disaster as exemplified by the decrease of hospital doctors

  16. Reducing operator radiation exposure during cardiac resynchronization therapy.

    Science.gov (United States)

    Brambilla, Marco; Occhetta, Eraldo; Ronconi, Martina; Plebani, Laura; Carriero, Alessandro; Marino, Paolo

    2010-12-01

    To quantify the reduction in equivalent dose at operator's hand that can be achieved by placement of a radiation-absorbing drape (RADPAD) during long-lasting cardiac resynchronization therapy (CRT) procedures. This is a prospective observational study that included 22 consecutive patients with drug-refractory heart failure who underwent implantation of a CRT device. The cases were randomly assigned to Group A (11 cases), performed without RADPAD, and to Group B (11 cases), performed using RADPAD. Dose equivalent at the examiner's hand was measured as H(p)(0.07) and as a time-adjusted H(p)(0.07) rate (mGy/min) with a direct reading dosimeter. The mean fluoroscopy time was 20.8 ± 7.7 min and the mean dose area product (DAP) was 118.6 ± 45.3 Gy cm(2). No significant differences were found between body mass index, fluoroscopy time, and DAP between patients examined with or without RADPAD. The correlation between the fluoroscopy time and the DAP was high (R(2) = 0.94, P RADPAD at the finger and hand were H(p)(0.07) = 1.27 ± 0.47 mGy per procedure and H(p)(0.07) rate = 0.057 ± 0.011 mGy/min, respectively. The dosage was reduced with the RADPAD to H(p)(0.07) = 0.48 ± 0.20 (P RADPAD. The use of the RADPAD in CRT devices implantation will make unlikely the necessity of limiting the yearly number of implants for high volume operators.

  17. Carnosine may reduce lung injury caused by radiation therapy.

    Science.gov (United States)

    Guney, Yildiz; Turkcu, Ummuhani Ozel; Hicsonmez, Ayse; Andrieu, Meltem Nalca; Guney, H Zafer; Bilgihan, Ayse; Kurtman, Cengiz

    2006-01-01

    Ionising radiation is known one of the most effective tools in the therapy of cancer but in many thoracic cancers, the total prescribed dose of radiation that can be safely administered to the target volume is limited by the risk of complications arising in the normal lung tissue. One of the major reasons for cellular injury after radiation is the formation of reactive oxygen species (ROS). Radiation pneumonitis is an acute phase side-effect which generally subsides after a few weeks and is followed by a chronic phase characterized by inflammation and fibrosis, that can develop months or years after irradiation. Carnosine is a dipeptide composed by the amino acids beta-histidine and l-alanine. The exact biological role of carnosine is not totally understood, but several studies have demonstrated that it possesses strong and specific antioxidant properties, protects against radiation damage,and promotes wound healing. The antioxidant mechanism of carnosine is attributed to its chelating effect against metal ions, superoxide dismutase (SOD)-like activity, ROS and free radicals scavenging ability . Either its antioxidant or anti-inflammatuar properties, we propose that carnosine ameliorates irradiation-induced lung injury. Thus, supplementing cancer patients to whom applied radiation therapy with carnosine, may provide an alleviation of the symptoms due to radiation-induced lung injury. This issue warrants further studies.

  18. A conservation paradox in the Great Basin—Altering sagebrush landscapes with fuel breaks to reduce habitat loss from wildfire

    Science.gov (United States)

    Shinneman, Douglas J.; Aldridge, Cameron L.; Coates, Peter S.; Germino, Matthew J.; Pilliod, David S.; Vaillant, Nicole M.

    2018-03-15

    Interactions between fire and nonnative, annual plant species (that is, “the grass/fire cycle”) represent one of the greatest threats to sagebrush (Artemisia spp.) ecosystems and associated wildlife, including the greater sage-grouse (Centrocercus urophasianus). In 2015, U.S. Department of the Interior called for a “science-based strategy to reduce the threat of large-scale rangeland fire to habitat for the greater sage-grouse and the sagebrush-steppe ecosystem.” An associated guidance document, the “Integrated Rangeland Fire Management Strategy Actionable Science Plan,” identified fuel breaks as high priority areas for scientific research. Fuel breaks are intended to reduce fire size and frequency, and potentially they can compartmentalize wildfire spatial distribution in a landscape. Fuel breaks are designed to reduce flame length, fireline intensity, and rates of fire spread in order to enhance firefighter access, improve response times, and provide safe and strategic anchor points for wildland fire-fighting activities. To accomplish these objectives, fuel breaks disrupt fuel continuity, reduce fuel accumulation, and (or) increase plants with high moisture content through the removal or modification of vegetation in strategically placed strips or blocks of land.Fuel breaks are being newly constructed, enhanced, or proposed across large areas of the Great Basin to reduce wildfire risk and to protect remaining sagebrush ecosystems (including greater sage-grouse habitat). These projects are likely to result in thousands of linear miles of fuel breaks that will have direct ecological effects across hundreds of thousands of acres through habitat loss and conversion. These projects may also affect millions of acres indirectly because of edge effects and habitat fragmentation created by networks of fuel breaks. Hence, land managers are often faced with a potentially paradoxical situation: the need to substantially alter sagebrush habitats with fuel breaks

  19. Enhanced rice production but greatly reduced carbon emission following biochar amendment in a metal-polluted rice paddy.

    Science.gov (United States)

    Zhang, Afeng; Bian, Rongjun; Li, Lianqing; Wang, Xudong; Zhao, Ying; Hussain, Qaiser; Pan, Genxing

    2015-12-01

    Soil amendment of biochar (BSA) had been shown effective for mitigating greenhouse gas (GHG) emission and alleviating metal stress to plants and microbes in soil. It has not yet been addressed if biochar exerts synergy effects on crop production, GHG emission, and microbial activity in metal-polluted soils. In a field experiment, biochar was amended at sequential rates at 0, 10, 20, and 40 t ha(-1), respectively, in a cadmium- and lead-contaminated rice paddy from the Tai lake Plain, China, before rice cropping in 2010. Fluxes of soil carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) were monitored using a static chamber method during the whole rice growing season (WRGS) of 2011. BSA significantly reduced soil CaCl2 extractable pool of Cd, and DTPA extractable pool of Cd and Pb. As compared to control, soil CO2 emission under BSA was observed to have no change at 10 t ha(-1) but decreased by 16-24% at 20 and 40 t ha(-1). In a similar trend, BSA at 20 and 40 t ha(-1) increased rice yield by 25-26% and thus enhanced ecosystem CO2 sequestration by 47-55% over the control. Seasonal total N2O emission was reduced by 7.1, 30.7, and 48.6% under BSA at 10, 20, and 40 t ha(-1), respectively. Overall, a net reduction in greenhouse gas balance (NGHGB) by 53.9-62.8% and in greenhouse gas intensity (GHGI) by 14.3-28.6% was observed following BSA at 20 and 40 t ha(-1). The present study suggested a great potential of biochar to enhancing grain yield while reducing carbon emission in metal-polluted rice paddies.

  20. Histomorphologic change of radiation pneumonitis in rat lungs: captopril reduces rat lung injury induced by irradiation

    International Nuclear Information System (INIS)

    Kim, Jin Hee

    1999-01-01

    To assess the histomorphologic changes in the rat lung injury induced by radiation, to determine whether captopril reduces the rat lung injury and to evaluate change in TNF-α and TGF β and rat lung damage by radiation and captopril. Right lungs in male Sprague-Dawley rats were divided irradiation alone (10, 20, 30 Gy) or radiation (same dose with radiation alone group) with captopril (500 mg/L). Radiation alone group were sacrificed at twelve hours and eleven weeks after radiation and radiation with captopril group (captopril group) were sacrificed at eleven weeks after radiation with captopril. We examined the light microscope and electron microscopic features in the groups. In radiation alone group, there were patch parenchymal collapse and consolidation at twelve hours after radiation. The increase of radiation dose shows more prominent the severity and broader the affected areas. Eleven weeks after radiation, the severity and areas of fibrosis had increased in proportion to radiation dose given in the radiation alone group. There was notable decrease of lung fibrosis in captopril group than in radiation alone group. The number of mast cells rapidly increased with increase of radiation dose in radiation alone group and the degree of increase of mast cell number and severity of collagen accumulation more decreased in captopril group than in radiation alone group. In radiation alone group expression of TNF-α and TGF-β] increased according to increase of radiation dose at twelve hours after radiation in both group. At eleven weeks after radiation, expression of TGF- P increased according to increase of radiation dose in radiation group but somewhat decreased in captopril group. In the captopril group the collagen deposition increased but less dense than those of radiation alone group. The severity of perivascular thickening, capillary change, the number and degranulation of mast cells more decreased in the captopril group than in the radiation alone group. It

  1. A strontium lattice clock with reduced blackbody radiation shift

    Energy Technology Data Exchange (ETDEWEB)

    Al-Masoudi, Ali Khalas Anfoos

    2016-09-30

    Optical clocks have been quickly moving to the forefront of the frequency standards field due to their high spectral resolution, and therefore the potential high stability and accuracy. The accuracy and stability of the optical clocks are nowadays two orders of magnitude better than microwave Cs clocks, which realize the SI second. Envisioned applications of highly accurate optical clocks are to perform tests of fundamental physics, for example, searching for temporal drifts of the fine structure constant α, violations of the Local Position Invariance (LPI), dark matter and dark energy, or to performance relativistic geodesy. In this work, the uncertainty of a strontium lattice clock, based on the {sup 1}S{sub 0}-{sup 3}P{sub 0} transition in {sup 87}Sr, due to the blackbody radiation (BBR) shift has been reduced to less than 1 x 10{sup -18} by more than one order of magnitude compared to the previous evaluation of the BBR shift uncertainty in this clock. The BBR shift has been reduced by interrogating the atoms in a cryogenic environment. The systematic uncertainty of the cryogenic lattice clock is evaluated to be 1.3 x 10{sup -17} which is dominated by the uncertainty of the AC Stark shift of the lattice laser and the uncertainty contribution of the BBR shift is negligible. Concerning the instability of the clock, the detection noise of the clock has been measured, and a model linking noise and clock instability has been developed. This noise model shows that, in our lattice clock, quantum projection noise is reached if more than 130 atoms are interrogated. By combining the noise model with the degradation due to the Dick effect reflecting the frequency noise of the interrogation laser, the instability of the clock is estimated to be 1.6 x 10{sup -16}/√(τ/s) in regular operation. During this work, several high-accuracy comparisons to other atomic clocks have been performed, including several absolute frequency measurements. The Sr clock transition frequency

  2. The great wall in the CfA survey: Its origin and imprint on the microwave background radiation

    International Nuclear Information System (INIS)

    Atrio-Barandela, F.; Kashlinsky, A.

    1990-01-01

    The Great Wall (GW) found in the latest CfA survey has clearly started out as an aspherical overdense region. We model its evolution after recombination and the imprint its time-dependent gravitational potential leaves on the microwave background radiation (MBR). We approximate GW as an oblate ellipsoid and show that it started at recombination with an almost spherical shape, but with an initial density contrast, δ i , much smaller than it had to be in the spherical model in order to reach the observed GW density contrast of q∝5. The resultant δ i is compatible with the r.m.s. value of δρ/ρ on the GW scale at recombination for models with the n -6 -5 depending on Ω and q. Therefore, MBR observations in that direction can further constrain Ω and the bias factor of the light distribution. (orig.)

  3. Does fast-neutron radiotherapy merely reduce the radiation dose

    International Nuclear Information System (INIS)

    Ando, Koichi

    1984-01-01

    We examined whether fast-neutron radiotherapy is superior to low-LET radiotherpy by comparing the relationship between cell survival and tumor control probabilities after exposure of tumor-bearing (species) to the two modalities. Analysis based on TCD 50 assay and lung colony assay indicated that single dose of fast neutron achieved animal cures at higher survival rates than other radiation modalities including single and fractionated γ-ray doses, fractionated doses of fast neutron, and the mixed-beam scheme with a sequence of N-γ-γ-γ-N. We conclude that fast-neutron radiotherapy cured animal tumors with lower cell killing rates other radiation modalities. (author)

  4. Preconcentration of a low-grade uranium ore yielding tailings of greatly reduced environmental concerns. Part V

    International Nuclear Information System (INIS)

    Raicevic, D.; Raicevic, M.

    1980-11-01

    The low-grade ore sample used for this investigation contained 0.057 percent uranium with uranothorite as the major uranium-bearing mineral and a small amount of brannerite, occurring in the quartz-sericite matrix of a conglomerate. The preconcentration procedures, consisting of pyrite flotation with or without flotation of radioactive minerals, followed by high intensity wet magnetic treatment of the sized flotation tailings, produced pyrite and radioactive concentrates of acceptable uranium grades ranging from 0.1 to 0.135 percent uranium. The combined concentrates comprised 37 to 49 percent of the ore by weight with the following combined recoveries: 95.6 to 97.9 percent of the uranium; 94.7 to 96.3 percent of the radium; 97.8 to 99.3 percent of the thorium over 98 percent of the pyrite. The preconcentration tailings produced comprised between 51 and 63 percent of the ore by weight and contained from: 0.0022 to 0.0037 percent U; 12 to 17 pCi/g Ra; 0.002 to 0.004 percent Th less than 0.03 percent S. Because these tailings are practically pyrite-free, they should not generate acidic conditions. Due to their low radium content, their radionuclide hazards are greatly reduced. These preconcentration tailings therefore, could be suitable for surface disposal, mine backfill, revegetation or other uses

  5. Reducing Human Radiation Risks on Deep Space Missions

    Science.gov (United States)

    2017-09-01

    101 Figure 49. Human Health, Life Support, and Habitation System...2013). These same studies reveal that for astronauts returning home, this may result in significant loss of lifespan and quality of life due to...warnings to the satellites in orbit at either planet , or to spacecraft in transit (Phys.org 2010). C. IMPROVEMENTS TO MEASUREMENTS OF SPACE RADIATION

  6. Relative efficacy for radiation reducing methods in scoliotic patients

    International Nuclear Information System (INIS)

    Aikenhead, J.; Triano, J.; Baker, J.

    1989-01-01

    Radiation dosages to sensitive organs in full spine radiography have in recent years been a concern of physicians as well as the general public. The spine is the prime target for exposure in scoliosis radiography, though the exposure usually necessitates irradiation of several radio-sensitive organs. In recent studies, various protection techniques have been used including various lead and aluminum filtration systems, altered patient positioning and varied tube-film distances. The purpose of this study was to evaluate the efficiency for radiation dosage reduction of three filtration systems used frequently in the chiropractic profession. The systems tested were the Nolan Multiple X-ray Filters, the Clear-Pb system and the Sportelli Wedge system. These systems were tested in seven configurations varying breast shielding, distance and patient positioning. All systems tested demonstrated significant radiation reductions to organs, especially breast tissue. The Clear-Pb system appeared to be the most effective for all organs except the breast, and the Sportelli Wedge system demonstrated the greatest reduction to breast tissue

  7. Vision 20/20: Increased image resolution versus reduced radiation exposure

    International Nuclear Information System (INIS)

    Ritman, Erik L.

    2008-01-01

    patterns resulting from moving grids which alter the refraction of x rays, that have passed through the body, in a predictable fashion, and (3) theoretically, by an image generated from the change in time-of-flight of x-ray photons passing through the body. Imaging phase shift or change in time-of-flight, rather than attenuation, of x-ray photons through tissues presents formidable technological problems for whole-body 3D imaging. However, if achievable in a routine clinical setting, these approaches have the potential for greatly expanding the use of x-ray imaging for screening. This overview examines the increased contrast resolution and reduced radiation exposure that might be achievable by the above-mentioned methods

  8. Efficacy of a radiation safety education initiative in reducing radiation exposure in the pediatric IR suite

    International Nuclear Information System (INIS)

    Sheyn, David D.; Racadio, John M.; Patel, Manish N.; Racadio, Judy M.; Johnson, Neil D.; Ying, Jun

    2008-01-01

    The use of ionizing radiation is essential for diagnostic and therapeutic imaging in the interventional radiology (IR) suite. As the complexity of procedures increases, radiation exposure risk increases. We believed that reinforcing staff education and awareness would help optimize radiation safety. To evaluate the effect of a radiation safety education initiative on IR staff radiation safety practices and patient radiation exposure. After each fluoroscopic procedure performed in the IR suite during a 4-month period, dose-area product (DAP), fluoroscopy time, and use of shielding equipment (leaded eyeglasses and hanging lead shield) by IR physicians were recorded. A lecture and article were then given to IR physicians and technologists that reviewed ALARA principles for optimizing radiation dose. During the following 4 months, those same parameters were recorded after each procedure. Before education 432 procedures were performed and after education 616 procedures were performed. Physician use of leaded eyeglasses and hanging shield increased significantly after education. DAP and fluoroscopy time decreased significantly for uncomplicated peripherally inserted central catheters (PICC) procedures and non-PICC procedures after education, but did not change for complicated PICC procedures. Staff radiation safety education can improve IR radiation safety practices and thus decrease exposure to radiation of both staff and patients. (orig.)

  9. One of the great conundrums of the 20th century science - ionizing radiation: Radiation processing and applications in the Czech Lands

    International Nuclear Information System (INIS)

    Janovsky, I.

    2007-01-01

    The article deals with the following topics: Milestones in the early history of radiation and radiation sources (1895-1954); Radiation effects - early observations and further development; Scope of radiation processing; Radiation processing in the Czech Lands (i.e. Bohemia + Moravia = the Czech part of Czechoslovakia or Austria-Hungary till 1918) (radiation sterilization of medical items; radiation processing of cable insulations; radiation preservation of objects of art and historical monuments; radiation modification of semiconductors; radiation synthesis of organic compounds; food irradiation; application of ionizing radiation in agriculture and gardening; radiation regeneration of water wells; radiation degradation of chlorinated biphenyls; radiation coloration of glass for decorative purposes; some other applications; and problems associated with practical radiation processing). An overview of 60 Co gamma irradiators and electron accelerators installed at Czech institutions is presented in the tabular form. (P.A.)

  10. Role of American Nuclear Insurers in reducing occupational radiation exposure

    International Nuclear Information System (INIS)

    Forbes, J.L.

    1980-01-01

    Since 1957 the nuclear insurance pools have provided liability and property insurance for the nation's nuclear power generating stations as mandated by the Price-Anderson Act. Although the insurance was originally structured to give financial protection to the insured in the event of a major accident, the potential for third-party claims arising from routine occupational exposure is becoming a more realistic pathway for a loss to the pools. In order to give maximum protection to the pools' assets, the Liability Engineering Department of American Nuclear Insurers (ANI) performs periodic inspections of the power plants. By concentrating on programs and management areas, ANI inspections complement regulatory inspections so that all major areas of common interest are reviewed. This paper presents the nature, results, and findings of those periodic inspections particularly in the general area of plant radiation protection

  11. Advances in Nuclear Power Plant Water Chemistry in Reducing Radiation Exposure

    International Nuclear Information System (INIS)

    Febrianto

    2005-01-01

    Water quality in light water reactor in Pressurized Water Reactor as well as in Boiling Water Reactor has being gradually improved since the beginning, to reduce corrosion risk and radiation exposure level. Corrosion problem which occurred to both type of reactors can reduce the plants availability, increase the operation and maintenance cost and increase the radiation exposure. Corrosion and radiation exposure risk in both reactor rare different. BWR type reactor has more experiences in corrosion problem because at the type of reactor lets water to boil in the core, while at PWR type reactor, water is kept not to boil. The BWR reactor has also higher radiation exposure rather than the PWR one. Many collaborative efforts of plants manufacturers and plant operator utilities have been done to reduce the radiation exposure level and corrosion risk. (author)

  12. Numerical study on similarity of plume infrared radiation between reduced-scale solid rocket motors

    Directory of Open Access Journals (Sweden)

    Zhang Xiaoying

    2016-08-01

    Full Text Available This study seeks to determine the similarities in plume radiation between reduced and full-scale solid rocket models in ground test conditions through investigation of flow and radiation for a series of scale ratios ranging from 0.1 to 1. The radiative transfer equation (RTE considering gas and particle radiation in a non-uniform plume has been adopted and solved by the finite volume method (FVM to compute the three dimensional, spectral and directional radiation of a plume in the infrared waveband 2–6 μm. Conditions at wavelengths 2.7 μm and 4.3 μm are discussed in detail, and ratios of plume radiation for reduced-scale through full-scale models are examined. This work shows that, with increasing scale ratio of a computed rocket motor, area of the high-temperature core increases as a 2 power function of the scale ratio, and the radiation intensity of the plume increases with 2–2.5 power of the scale ratio. The infrared radiation of plume gases shows a strong spectral dependency, while that of Al2O3 particles shows spectral continuity of gray media. Spectral radiation intensity of a computed solid rocket plume’s high temperature core increases significantly in peak radiation spectra of plume gases CO and CO2. Al2O3 particles are the major radiation component in a rocket plume. There is good similarity between contours of plume spectral radiance from different scale models of computed rockets, and there are two peak spectra of radiation intensity at wavebands 2.7–3.0 μm and 4.2–4.6 μm. Directed radiation intensity of the entire plume volume will rise with increasing elevation angle.

  13. Mometasone Furoate Cream Reduces Acute Radiation Dermatitis in Patients Receiving Breast Radiation Therapy: Results of a Randomized Trial

    International Nuclear Information System (INIS)

    Hindley, Andrew; Zain, Zakiyah; Wood, Lisa; Whitehead, Anne; Sanneh, Alison; Barber, David; Hornsby, Ruth

    2014-01-01

    Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MF than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected

  14. Mometasone Furoate Cream Reduces Acute Radiation Dermatitis in Patients Receiving Breast Radiation Therapy: Results of a Randomized Trial

    Energy Technology Data Exchange (ETDEWEB)

    Hindley, Andrew, E-mail: andrew.hindley@lthtr.nhs.uk [Rosemere Cancer Centre, Royal Preston Hospital, Preston (United Kingdom); Zain, Zakiyah [College of Arts and Sciences, Universiti Utara Malaysia, Kedah (Malaysia); Wood, Lisa [Department of Social Sciences, Lancaster Medical School, Lancaster (United Kingdom); Whitehead, Anne [Medical and Pharmaceutical Statistics Research Unit, Lancaster University, Lancaster (United Kingdom); Sanneh, Alison; Barber, David; Hornsby, Ruth [Rosemere Cancer Centre, Royal Preston Hospital, Preston (United Kingdom)

    2014-11-15

    Purpose: We wanted to confirm the benefit of mometasone furoate (MF) in preventing acute radiation reactions, as shown in a previous study (Boström et al, Radiother Oncol 2001;59:257-265). Methods and Materials: The study was a double-blind comparison of MF with D (Diprobase), administered daily from the start of radiation therapy for 5 weeks in patients receiving breast radiation therapy, 40 Gy in 2.67-Gy fractions daily over 3 weeks. The primary endpoint was mean modified Radiation Therapy Oncology Group (RTOG) score. Results: Mean RTOG scores were significantly less for MF than for D (P=.046). Maximum RTOG and mean erythema scores were significantly less for MF than for D (P=.018 and P=.012, respectively). The Dermatology Life Quality Index (DLQI) score was significantly less for MF than for D at weeks 4 and 5 when corrected for Hospital Anxiety and Depression (HAD) questionnaire scores. Conclusions: MF cream significantly reduces radiation dermatitis when applied to the breast during and after radiation therapy. For the first time, we have shown a significantly beneficial effect on quality of life using a validated instrument (DLQI), for a topical steroid cream. We believe that application of this cream should be the standard of care where radiation dermatitis is expected.

  15. Measures to reduce occupational radiation exposure in PET facilities from nurses' point of view

    International Nuclear Information System (INIS)

    Miyazawa, Keiko; Takahashi, Juri; Mochiduki, Yoshikazu

    2006-01-01

    In parallel with the increase in the number of institutions having PET facilities, the number of nurse working in these facilities has also increased, and the issue of occupational radiation exposure has assumed ever greater importance. In our clinic, since nurses have started to administer FDG intravenous injections, their annual radiation exposure has amounted to 4.8 - 7.1 mSv. To reduce their annual radiation exposure to less than 5 mSv, we identified sources of increased exposure and considered countermeasures based on this information. By implementing countermeasures such as improvements in daily working conditions and ways to avoid various troubles, it was possible to reduce the annual radiation exposure of all nurses to less than 5 mSv. Our experience demonstrates that to provide a working environment with a minimum of occupational radiation exposure, educational training and enhancement of knowledge and technical skills are vital. (author)

  16. Image noise reduction technology reduces radiation in a radial-first cardiac catheterization laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Gunja, Ateka; Pandey, Yagya [Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL (United States); Division of Cardiology, Department of Medicine, University of Illinois at Chicago, Chicago, IL (United States); Xie, Hui [Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL (United States); Faculty of Health Sciences, Simon Fraser University, Burnaby, BC (Canada); Wolska, Beata M. [Department of Physiology and Biophysics, Center for Cardiovascular Research, University of Illinois at Chicago, Chicago, IL (United States); Shroff, Adhir R.; Ardati, Amer K. [Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL (United States); Division of Cardiology, Department of Medicine, University of Illinois at Chicago, Chicago, IL (United States); Vidovich, Mladen I., E-mail: miv@uic.edu [Department of Veterans Affairs, Jesse Brown VA Medical Center, Chicago, IL (United States); Division of Cardiology, Department of Medicine, University of Illinois at Chicago, Chicago, IL (United States)

    2017-04-15

    Background: Transradial coronary angiography (TRA) has been associated with increased radiation doses. We hypothesized that contemporary image noise reduction technology would reduce radiation doses in the cardiac catheterization laboratory in a typical clinical setting. Methods and results: We performed a single-center, retrospective analysis of 400 consecutive patients who underwent diagnostic and interventional cardiac catheterizations in a predominantly TRA laboratory with traditional fluoroscopy (N = 200) and a new image noise reduction fluoroscopy system (N = 200). The primary endpoint was radiation dose (mGy cm{sup 2}). Secondary endpoints were contrast dose, fluoroscopy times, number of cineangiograms, and radiation dose by operator between the two study periods. Radiation was reduced by 44.7% between the old and new cardiac catheterization laboratory (75.8 mGy cm{sup 2} ± 74.0 vs. 41.9 mGy cm{sup 2} ± 40.7, p < 0.0001). Radiation was reduced for both diagnostic procedures (45.9%, p < 0.0001) and interventional procedures (37.7%, p < 0.0001). There was no statistically significant difference in radiation dose between individual operators (p = 0.84). In multivariate analysis, radiation dose remained significantly decreased with the use of the new system (p < 0.0001) and was associated with weight (p < 0.0001), previous coronary artery bypass grafting (p < 0.0007) and greater than 3 stents used (p < 0.0004). TRA was used in 90% of all cases in both periods. Compared with a transfemoral approach (TFA), TRA was not associated with higher radiation doses (p = 0.20). Conclusions: Image noise reduction technology significantly reduces radiation dose in a contemporary radial-first cardiac catheterization clinical practice. - Highlights: • Radial arterial access has been associated with higher doses compared to femoral access. • In a radial-first cardiac catheterization laboratory (90% radial) we examined radiation doses reduction with a contemporary image

  17. Image noise reduction technology reduces radiation in a radial-first cardiac catheterization laboratory

    International Nuclear Information System (INIS)

    Gunja, Ateka; Pandey, Yagya; Xie, Hui; Wolska, Beata M.; Shroff, Adhir R.; Ardati, Amer K.; Vidovich, Mladen I.

    2017-01-01

    Background: Transradial coronary angiography (TRA) has been associated with increased radiation doses. We hypothesized that contemporary image noise reduction technology would reduce radiation doses in the cardiac catheterization laboratory in a typical clinical setting. Methods and results: We performed a single-center, retrospective analysis of 400 consecutive patients who underwent diagnostic and interventional cardiac catheterizations in a predominantly TRA laboratory with traditional fluoroscopy (N = 200) and a new image noise reduction fluoroscopy system (N = 200). The primary endpoint was radiation dose (mGy cm"2). Secondary endpoints were contrast dose, fluoroscopy times, number of cineangiograms, and radiation dose by operator between the two study periods. Radiation was reduced by 44.7% between the old and new cardiac catheterization laboratory (75.8 mGy cm"2 ± 74.0 vs. 41.9 mGy cm"2 ± 40.7, p < 0.0001). Radiation was reduced for both diagnostic procedures (45.9%, p < 0.0001) and interventional procedures (37.7%, p < 0.0001). There was no statistically significant difference in radiation dose between individual operators (p = 0.84). In multivariate analysis, radiation dose remained significantly decreased with the use of the new system (p < 0.0001) and was associated with weight (p < 0.0001), previous coronary artery bypass grafting (p < 0.0007) and greater than 3 stents used (p < 0.0004). TRA was used in 90% of all cases in both periods. Compared with a transfemoral approach (TFA), TRA was not associated with higher radiation doses (p = 0.20). Conclusions: Image noise reduction technology significantly reduces radiation dose in a contemporary radial-first cardiac catheterization clinical practice. - Highlights: • Radial arterial access has been associated with higher doses compared to femoral access. • In a radial-first cardiac catheterization laboratory (90% radial) we examined radiation doses reduction with a contemporary image-noise compared to

  18. A Reduced-order NLTE Kinetic Model for Radiating Plasmas of Outer Envelopes of Stellar Atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Munafò, Alessandro [Aerospace Engineering Department, University of Illinois at Urbana-Champaign, 206A Talbot Lab., 104 S. Wright Street, Urbana, IL 61801 (United States); Mansour, Nagi N. [NASA Ames Research Center, Moffett Field, 94035 CA (United States); Panesi, Marco, E-mail: munafo@illinois.edu, E-mail: nagi.n.mansour@nasa.gov, E-mail: m.panesi@illinois.edu [Aerospace Engineering Department, University of Illinois at Urbana-Champaign, 306 Talbot Lab., 104 S. Wright Street, Urbana, IL 61801 (United States)

    2017-04-01

    The present work proposes a self-consistent reduced-order NLTE kinetic model for radiating plasmas found in the outer layers of stellar atmospheres. A detailed collisional-radiative kinetic mechanism is constructed by leveraging the most up-to-date set of ab initio and experimental data available in the literature. This constitutes the starting point for the derivation of a reduced-order model, obtained by lumping the bound energy states into groups. In order to determine the needed thermo-physical group properties, uniform and Maxwell–Boltzmann energy distributions are used to reconstruct the energy population of each group. Finally, the reduced set of governing equations for the material gas and the radiation field is obtained based on the moment method. Applications consider the steady flow across a shock wave in partially ionized hydrogen. The results clearly demonstrate that adopting a Maxwell–Boltzmann grouping allows, on the one hand, for a substantial reduction of the number of unknowns and, on the other, to maintain accuracy for both gas and radiation quantities. Also, it is observed that, when neglecting line radiation, the use of two groups already leads to a very accurate resolution of the photo-ionization precursor, internal relaxation, and radiative cooling regions. The inclusion of line radiation requires adopting just one additional group to account for optically thin losses in the α , β , and γ lines of the Balmer and Paschen series. This trend has been observed for a wide range of shock wave velocities.

  19. Ways of reducing radiation exposure in a future nuclear power economy

    International Nuclear Information System (INIS)

    Morgan, K.Z.

    1976-01-01

    The reasons for attempting to reduce radiation exposure in a future nuclear power economy are first discussed. This is followed by a detailed examination of ways for reducing exposures. The entire fuel cycle from uranium mining through fuel reprocessing is covered but special attention is devoted to reactors, fuel and waste shipping and fuel reprocessing

  20. Updated estimates of the proportion of childhood leukaemia incidence in Great Britain that may be caused by natural background ionising radiation

    International Nuclear Information System (INIS)

    Little, Mark P; Wakeford, Richard; Kendall, Gerald M

    2009-01-01

    The aetiology of childhood leukaemia remains generally unknown, although exposure to moderate and high levels of ionising radiation, such as was experienced during the atomic bombings of Japan or from radiotherapy, is an established cause. Risk models based primarily upon studies of the Japanese A-bomb survivors imply that low-level exposure to ionising radiation, including to ubiquitous natural background radiation, also raises the risk of childhood leukaemia. In a recent paper (Wakeford et al 2009 Leukaemia 23 770-6) we estimated the proportion of childhood leukaemia incidence in Great Britain attributable to natural background radiation to be about 20%. In this paper we employ the two sets of published leukaemia risk models used previously, but use recently published revised estimates of natural background radiation doses received by the red bone marrow of British children to update the previous results. Using the newer dosimetry we calculate that the best estimate of the proportion of cases of childhood leukaemia in Great Britain predicted to be attributable to this source of exposure is 15-20%, although the uncertainty associated with certain stages in the calculation (e.g. the nature of the transfer of risk between populations and the pertinent dose received from naturally occurring alpha-particle-emitting radionuclides) is significant. The slightly lower attributable proportions compared with those previously derived by Wakeford et al (Leukaemia 2009 23 770-6) are largely due to the lower doses (and in particular lower high LET doses) for the first year of life.

  1. Land-use change reduces habitat suitability for supporting managed honey bee colonies in the Northern Great Plains

    Science.gov (United States)

    Otto, Clint R.; Roth, Cali; Carlson, Benjamin; Smart, Matthew

    2016-01-01

    Human reliance on insect pollination services continues to increase even as pollinator populations exhibit global declines. Increased commodity crop prices and federal subsidies for biofuel crops, such as corn and soybeans, have contributed to rapid land-use change in the US Northern Great Plains (NGP), changes that may jeopardize habitat for honey bees in a part of the country that supports >40% of the US colony stock. We investigated changes in biofuel crop production and grassland land covers surrounding ∼18,000 registered commercial apiaries in North and South Dakota from 2006 to 2014. We then developed habitat selection models to identify remotely sensed land-cover and land-use features that influence apiary site selection by Dakota beekeepers. Our study demonstrates a continual increase in biofuel crops, totaling 1.2 Mha, around registered apiary locations in North and South Dakota. Such crops were avoided by commercial beekeepers when selecting apiary sites in this region. Furthermore, our analysis reveals how grasslands that beekeepers target when selecting commercial apiary locations are becoming less common in eastern North and South Dakota, changes that may have lasting impact on pollinator conservation efforts. Our study highlights how land-use change in the NGP is altering the landscape in ways that are seemingly less conducive to beekeeping. Our models can be used to guide future conservation efforts highlighted in the US national pollinator health strategy by identifying areas that support high densities of commercial apiaries and that have exhibited significant land-use changes.

  2. Assessing community values for reducing agricultural emissions to improve water quality and protect coral health in the Great Barrier Reef

    Science.gov (United States)

    Rolfe, John; Windle, Jill

    2011-12-01

    Policymakers wanting to increase protection of the Great Barrier Reef from pollutants generated by agriculture need to identify when measures to improve water quality generate benefits to society that outweigh the costs involved. The research reported in this paper makes a contribution in several ways. First, it uses the improved science understanding about the links between management changes and reef health to bring together the analysis of costs and benefits of marginal changes, helping to demonstrate the appropriate way of addressing policy questions relating to reef protection. Second, it uses the scientific relationships to frame a choice experiment to value the benefits of improved reef health, with the results of mixed logit (random parameter) models linking improvements explicitly to changes in "water quality units." Third, the research demonstrates how protection values are consistent across a broader population, with some limited evidence of distance effects. Fourth, the information on marginal costs and benefits that are reported provide policymakers with information to help improve management decisions. The results indicate that while there is potential for water quality improvements to generate net benefits, high cost water quality improvements are generally uneconomic. A major policy implication is that cost thresholds for key pollutants should be set to avoid more expensive water quality proposals being selected.

  3. The use of ultrasound and infrared radiation to reduce microbiological contamination of raw materials in the production of citric acid

    International Nuclear Information System (INIS)

    Sharova, N.Yu.; Kamen'kova, N.V.

    2012-01-01

    The microflora of the main raw materials for producing citric acid (beet molasses and grain) is capable of greatly reducing the yield of target metabolite or changing the focus of biosynthesis. Rye, oats and barley grain with humidity of 16% and its grinds (a particle size 1 mm) was treated ultrasound having a capacity of 1.5 kW, frequency 15 and 22 kHz. Infrared radiation treatment was carried out at t 120 to 180 degrees C for 2-30 min and the exposure power W/sq. cm. In molasses there were found spore-forming heat-resistant bacteria with Bacillus subtilis and B. mesentericus being predominated, gaseous, nitrite-forming, acid-forming bacteria, yeast of gen. Candida, Leuconostoc mesenteroides that consume sugar, nitric and mineral substances reducing the biosynthetic activity of Aspergillus niger producer. For molasses treated with ultrasound 1.5 kW and frequency 22 kHz, the total viable count reduces by the order compared to the control. Increasing the exposure time up to 30 min results in slightly reducing the achieved level. Under influence of ultrasound the contamination with bacteria and mold fungi of rye, oats and barley grain grinds reduces by 2-3 orders compared to the control and much more at frequency 22 kHz. The great increase in the parameter of the total viable count is achieved by IR-treatment of grain and grinds. The microflora practically entirely dies by increasing the temperature up to 160-180 degrees C even in case of 2 minute exposure. IR treatment providing t 120 degrees C for 2-6 min resulted in reducing the number of cells of microorganisms by 3-4 orders compared to the untreated control

  4. Possibilities to reduce the effect of ionizing radiation by interaction of two types of radiation into a matter: ionized and non-ionized radiation

    International Nuclear Information System (INIS)

    Tanvir

    2007-01-01

    Full text: At present it has been accepted that ionized radiation can cause biological effects on the human body and the only way of preventing this effect, is by shielding the source of radiation by absorbing materials. On the other hand, the technology of non-ionizing radiation is upgraded. The canalization of radiation through the wave-guide based structures and optical fiber is well established. This reminds us that passing through benzene non-ionized radiation give the 'Raman' effect, which can ensure the secondary generation of non-ionized radiation with the wave length of nanometer and so far. These types of non-ionized radiation can easily be correlated with the gamma radiation, which is ionized. We know that high-energized photon usually interacts with matter and reduces its energy to the matter and generate electro-magnetic waves into the molecules of the matter. It is also well known that through the wave-guide based structures and optical fiber; the path of energy distribution of photon is likely to be optical energetic modes. If two types of photon from two types of radiation (ionized and non-ionized) interact with matter and pass through the optical fiber, they can generate optical modes with various wavelengths and phase velocities. With 'Raman' effect we can generate secondary electromagnetic waves of nanometer; as well as optical modes into the optical fiber. These optical modes from two types of radiation with various phase velocities, having the similar wavelength, can decrease or accelerate some modes. On the view of signal distribution, we can assume that if two similar signals pass through the circuit with phase difference 180P 0 P, then the result posses no signal. We are also reminded that photon of γ - radiation can spread from 0 deg. to 180 deg. C, where the 'Compton' loss of radiation is minimum. In view of the electro-magnetic theory of Maxwell we can assume the energetic field of optical modes, which are generated into the optical

  5. Changes of reduced glutathion, glutathion reductase, and glutathione peroxidase after radiation in guinea pigs

    International Nuclear Information System (INIS)

    Erden, M.; Bor, N.M.

    1984-01-01

    In this series of experiments the protective action of reduced glutathion due to ionizing radiation has been studied. In the experimental group 18 guinea pigs were exposed to successive radiations of 150 rad 3 or 4 days apart. Total dose given amounted to 750 rad which is the LD50 for guinea pigs. Blood samples were taken 30 min after each exposure. The control series were sham radiated but otherwise treated identically. The cells of the removed blood samples were separated by centrifugation and were subjected to the reduced glutathion stability test. GSSGR, GPer, and LDH enzyme activities were also measured of which the latter served as a marked enzyme. It was found that LDH did not show any alteration after radiation. The reduced glutathion stability test showed a consistent but minor reduction (P greater than 0.05), in the experimental group. GSSGR enzyme activity on the other hand was reduced significantly (from 176.48 +/- 11.32 to 41.34 +/- 1.17 IU/ml of packed erythrocytes, P less than 0.001) in the same group. GPer activity showed a consistent but minor elevation during the early phase of the experimental group. It was later increased significantly beginning after 600 rad total radiation on the fourth session (P less than 0.050)

  6. Pretreatment of low dose radiation reduces radiation-induced apoptosis in mouse lymphoma (EL4) cells.

    Science.gov (United States)

    Kim, J H; Hyun, S J; Yoon, M Y; Ji, Y H; Cho, C K; Yoo, S Y

    1997-06-01

    Induction of an adaptive response to ionizing radiation in mouse lymphoma (EL4) cells was studied by using cell survival fraction and apoptotic nucleosomal DNA fragmentation as biological end points. Cells in early log phase were pre-exposed to low dose of gamma-rays (0.01 Gy) 4 or 20 hrs prior to high dose gamma-ray (4, 8 and 12 Gy for cell survival fraction analysis; 8 Gy for DNA fragmentation analysis) irradiation. Then cell survival fractions and the extent of DNA fragmentation were measured. Significant adaptive response, increase in cell survival fraction and decrease in the extent of DNA fragmentation were induced when low and high dose gamma-ray irradiation time interval was 4 hr. Addition of protein or RNA synthesis inhibitor, cycloheximide or 5,6-dichloro-1-beta-d-ribofuranosylbenzimidazole (DRFB), respectively during adaptation period, the period from low dose gamma-ray irradiation to high dose gamma-ray irradiation, was able to inhibit the induction of adaptive response, which is the reduction of the extent DNA fragmentation in irradiated EL4 cells. These data suggest that the induction of adaptive response to ionizing radiation in EL4 cells required both protein and RNA synthesis.

  7. Analytical study of the effects of the Low-Level Jet on moisture convergence and vertical motion fields at the Southern Great Plains Cloud and Radiation Testbed site

    Energy Technology Data Exchange (ETDEWEB)

    Bian, X.; Zhong, S.; Whiteman, C.D.; Stage, S.A. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-04-01

    The Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) is located in a region that is strongly affected by a prominent meteorological phenomenon--the Great Plains Low-Level Jet (LLJ). Observations have shown that the LLJ plays a vital role in spring and summertime cloud formation and precipitation over the Great Plains. An improved understanding of the LLJ characteristics and its impact on the environment is necessary for addressing the fundamental issue of development and testing of radiational transfer and cloud parameterization schemes for the general circulation models (GCMs) using data from the SGP CART site. A climatological analysis of the summertime LLJ over the SGP has been carried out using hourly observations from the National Oceanic and Atmospheric Administration (NOAA) Wind Profiler Demonstration Network and from the ARM June 1993 Intensive Observation Period (IOP). The hourly data provide an enhanced temporal and spatial resolution relative to earlier studies which used 6- and 12-hourly rawinsonde observations at fewer stations.

  8. A long-term study of aerosol–cloud interactions and their radiative effect at the Southern Great Plains using ground-based measurements

    Directory of Open Access Journals (Sweden)

    E. T. Sena

    2016-09-01

    Full Text Available Empirical estimates of the microphysical response of cloud droplet size distribution to aerosol perturbations are commonly used to constrain aerosol–cloud interactions in climate models. Instead of empirical microphysical estimates, here macroscopic variables are analyzed to address the influence of aerosol particles and meteorological descriptors on instantaneous cloud albedo and the radiative effect of shallow liquid water clouds. Long-term ground-based measurements from the Atmospheric Radiation Measurement (ARM program over the Southern Great Plains are used. A broad statistical analysis was performed on 14 years of coincident measurements of low clouds, aerosol, and meteorological properties. Two cases representing conflicting results regarding the relationship between the aerosol and the cloud radiative effect were selected and studied in greater detail. Microphysical estimates are shown to be very uncertain and to depend strongly on the methodology, retrieval technique and averaging scale. For this continental site, the results indicate that the influence of the aerosol on the shallow cloud radiative effect and albedo is weak and that macroscopic cloud properties and dynamics play a much larger role in determining the instantaneous cloud radiative effect compared to microphysical effects. On a daily basis, aerosol shows no correlation with cloud radiative properties (correlation = −0.01 ± 0.03, whereas the liquid water path shows a clear signal (correlation = 0.56 ± 0.02.

  9. Calorie restriction reduces the incidence of radiation-induced myeloid leukemia and spontaneous tumor

    International Nuclear Information System (INIS)

    Yoshida, Kazuko

    1999-01-01

    The host-defense mechanisms against cancers are known to be modulated by changing the environmental factor(s). The spontaneous incidence of myeloid leukemia is about 1% in C3H/He mice, and the incidence increases up to 23.3% when a single dose of radiation, 3 Gy X-ray, is exposed to a whole-body. Since calorie restriction was known to reduce the incidence of spontaneous tumors, a question as to whether such radiation induced-increase of myeloid leukemia would be also decreased by calorie restriction, was aimed to answer to elucidate possible mechanism of radiation-induced myeloid leukemia. By the calorie restriction, the incidence of myeloid leukemia was significantly decreased; it was reduced to 7.9% and 10.7% when restriction was started before (6 weeks old) and after (10 weeks old) irradiation, respectively. In addition, the latent period of the myeloid leukemia in the groups for calorie restriction was significantly extended at a greater extent as compared with the control diet groups. Number of hematopoietic stem cells, the possible target cells for radiation-induced leukemias, in the groups for the calorie restriction demonstrated a significant decrease, especially in the spleen, as compared with that in the control, when the evaluation was made at the time of radiation exposure. Then, we examined whether the decreased number of target cells at the time of exposure is caused by the reduction of radiation-induced myeloid leukemia with caloric restriction. The third restricted groups were fed 65 kcal diet (restricted diet) for the first 4 weeks i.e. from 6 weeks to 10 weeks old, then, the mice were fed with control diet after radiation. The incidence of myeloid leukemia in this group was slightly decreased but did not show statistically significance. Therefore, the caloric restriction seems to be more effective in the promotion stage than the initiation stage on radiation-induced leukemogenesis. It is well known that C3H/He mice develop hepatoma spontaneously

  10. Water Chemistry Control in Reducing Corrosion and Radiation Exposure at PWR Reactor

    International Nuclear Information System (INIS)

    Febrianto

    2006-01-01

    Water chemistry control plays an important role in relation to plant availability, reliability and occupational radiation exposures. Radiation exposures of nuclear plant workers are determined by the radiation rate dose and by the amount maintenance and repair work time Water chemistry has always been, from beginning of operation of power Pressurized Water Reactor, an important factor in determining the integrity of reactor components, fuel cladding integrity and minimize out of core radiation exposures. For primary system, the parameters to control the quality of water chemistry have been subject to change in time. Reactor water coolant pH need to be optimally controlled and be operated in range pH 6.9 to 7.4. At pH lower than 6.9, cause increasing the radiation exposure level and increasing coolant water pH higher than 7.4 will decrease radiation exposure level but increasing risk to fuel cladding and steam generator tube. Since beginning 90 decade, PWR water coolant pH tend to be operated at pH 7.4. This paper will discuss concerning water chemistry development in reducing corrosion and radiation exposure dose in PWR reactor. (author)

  11. Agricultural measures to reduce radiation doses to man caused by severe nuclear accidents

    International Nuclear Information System (INIS)

    Dorp, F. van; Eleveld, R.; Frissel, M.J.

    1981-01-01

    Agricultural land and products may become contaminated after a severe nuclear accident. If radiation doses to man caused by the ingestion of contaminated agricultural products from such areas will be unacceptably high, measures to reduce this radiation dose will have to be taken. Radiation doses to man can be estimated by using models which describe quantitatively the transfer of radionuclides through the biosphere. The following processes and pathways are described in this study: accidental releases into atmospheric environments and subsequent nearby deposition; contamination of crops by direct deposition and the subsequent short term pathway (e.g. grass-cow-milk-man); contamination of soil and the subsequent long term pathway (e.g. soil-crop-man, soil-grass-cattle-milk/meat-man). Depending on the degree of contamination and on the estimated radiation doses to man, various measures are advised. (Auth.)

  12. Development of a Simple Radioactive marker System to Reduce Positioning Errors in Radiation Treatment

    International Nuclear Information System (INIS)

    William H. Miller; Dr. Jatinder Palta

    2007-01-01

    The objective of this research is to implement an inexpensive, quick and simple monitor that provides an accurate indication of proper patient position during the treatment of cancer by external beam X-ray radiation and also checks for any significant changes in patient anatomy. It is believed that this system will significantly reduce the treatment margin, provide an additional, independent quality assurance check of positioning accuracy prior to all treatments and reduce the probability of misadministration of therapeutic dose

  13. Low Amount of Salinomycin Greatly Increases Akt Activation, but Reduces Activated p70S6K Levels

    Directory of Open Access Journals (Sweden)

    Sungpil Yoon

    2013-08-01

    Full Text Available The present study identified a novel salinomycin (Sal-sensitization mechanism in cancer cells. We analyzed the signal proteins Akt, Jnk, p38, Jak, and Erk1/2 in cancer cell lines that had arrested growth following low amounts of Sal treatment. We also tested the signal molecules PI3K, PDK1, GSK3β, p70S6K, mTOR, and PTEN to analyze the PI3K/Akt/mTOR pathway. The results showed that Sal sensitization positively correlates with large reductions in p70S6K activation. Interestingly, Akt was the only signal protein to be significantly activated by Sal treatment. The Akt activation appeared to require the PI3K pathway as its activation was abolished by the PI3K inhibitors LY294002 and wortmannin. The Akt activation by Sal was conserved in the other cell lines analyzed, which originated from other organs. Both Akt activation and C-PARP production were proportionally increased with increased doses of Sal. In addition, the increased levels of pAkt were not reduced over the time course of the experiment. Co-treatment with Akt inhibitors sensitized the Sal-treated cancer cells. The results thereby suggest that Akt activation is increased in cells that survive Sal treatment and resist the cytotoxic effect of Sal. Taken together; these results indicate that Akt activation may promote the resistance of cancer cells to Sal.

  14. Stem Cell Therapy to Reduce Radiation-Induced Normal Tissue Damage

    NARCIS (Netherlands)

    Coppes, Rob P.; van der Goot, Annemieke; Lombaert, Isabelle M. A.

    Normal tissue damage after radiotherapy is still a major problem in cancer treatment. Stem cell therapy may provide a means to reduce radiation-induced side effects and improve the quality of life of patients. This review discusses the current status in stem cell research with respect to their

  15. The principles of radiation protection

    International Nuclear Information System (INIS)

    2004-01-01

    The aim of radiation protection is to avoid or to reduce the risks linked to ionizing radiation. In order to reduce these risks, the radiation protection uses three great principles: justification, optimization and limitation of radiation doses. to apply these principles, the radiation protection has regulatory and technical means adapted to three different categories of people: public, patients and workers. The nuclear safety authority elaborates the regulation, and carries out monitoring of the reliable application of radiation protection system. (N.C.)

  16. External effective radiation dose to workers in the restricted area of the Fukushima Daiichi Nuclear Power Plant during the third year after the Great East Japan Earthquake

    International Nuclear Information System (INIS)

    Sakumi, Akira; Miyagawa, Ryu; Tamari, Yuki; Nawa, Kanabu; Sakura, Osamu; Nakagawa, Keiichi

    2016-01-01

    Since the Great East Japan Earthquake on 11 March 2011, Iitate Village has continued to be classified as a deliberate evacuation area, in which residents are estimated to receive an annual additional effective radiation dose of >20 mSv. Some companies still operate in Iitate Village, with a special permit from the Cabinet Office Team in Charge of Assisting the Lives of Disaster Victims. In this study, we measured the annual effective radiation dose to workers in Iitate Village from 15 January to 13 December 2013. The workers stayed in Iitate for 10 h and left the village for the remaining 14 h each working day. They worked for 5 days each week in Iitate Village, but stayed outside of the village for the remaining 2 days each week. We found that the effective radiation dose of 70% of the workers was <2 mSv, including natural radiation; the maximum dose was 3.6 mSv. We estimated the potential annual additional effective radiation dose if people returned full-time to Iitate. Our analysis supports the plan for people to return to their home village at the end of 2017

  17. Reducing radiation exposure in an electrophysiology lab with introduction of newer fluoroscopic technology

    Directory of Open Access Journals (Sweden)

    Munish Sharma

    2017-09-01

    Full Text Available The use of fluoroscopic devices exposes patients and operators to harmful effects of ionizing radiation in an electrophysiology (EP lab. We sought to know if the newer fluoroscopic technology (Allura Clarity installed in a hybrid EP helps to reduce prescribed radiation dose. We performed radiation dose analysis of 90 patients who underwent various procedures in the EP lab at a community teaching hospital after the introduction of newer fluoroscopic technology in June of 2016.Watchman device insertion, radiofrequency ablation procedures, permanent pacemaker (PPM/implantable cardioverter defibrillator (ICD placement and battery changes were included in the study to compare radiation exposure during different procedures performed commonly in an EP lab. In all cases of watchman device placement, radiofrequency ablation procedures, PPM/ICD placement and battery changes, there was a statistically significant difference (<0.05 in radiation dose exposure. Significant reduction in radiation exposure during various procedures performed in an EP lab was achieved with aid of newer fluoroscopic technology and better image detection technology.

  18. New radiation mitigators to reduce bone marrow death of mice by post-irradiation administration

    International Nuclear Information System (INIS)

    Anzai, Kazunori

    2009-01-01

    We have found recently that heat-treated mineral yeast preparations and water-soluble analogs of vitamin E are potent radiation mitigator to reduce bone marrow death of mice by post-irradiation administration. When administered immediately after whole-body X-irradiation (7.5 Gy), both Zn-yeast and γ-tocopherol dimethylglycine ester (TDMG) significantly increased the viability of mice from 0% (control) to more than 90% (treated). Zn-yeast did not inhibit the tumor-regulation by γ-rays but even sensitize the radiation effect in mice xenografts of HeLa cells. (author)

  19. Who was concerned about radiation, food safety, and natural disasters after the great East Japan earthquake and Fukushima catastrophe? A nationwide cross-sectional survey in 2012.

    Science.gov (United States)

    Sugimoto, Takashi; Shinozaki, Tomohiro; Naruse, Takashi; Miyamoto, Yuki

    2014-01-01

    Disaster-related concerns by sub-populations have not been clarified after the great East Japan earthquake and the Fukushima nuclear power plant incidents. This paper assesses who was concerned about radiation, food safety, and natural disasters among the general population in order to buffer such concerns effectively. The hypothesis that women, parents, and family caregivers were most concerned about radiation, food safety, and natural disaster was tested using a varying-intercept multivariable logistic regression with 5809 responses from a nationwide cross-sectional survey random-sampled in March 2012. Many people were at least occasionally concerned about radiation (53.5%), food safety (47.3%), and about natural disaster (69.5%). Women were more concerned than men about radiation (OR = 1.67; 95% CI = 1.35-2.06), food safety (1.70; 1.38-2.10), and natural disasters (1.74; 1.39-2.19). Parents and family care needs were not significant. Married couples were more concerned about radiation (1.53; 1.33-1.77), food safety (1.38; 1.20-1.59), and natural disasters (1.30; 1.12-1.52). Age, child-cohabitation, college-completion, retirement status, homemaker status, and the house-damage certificate of the last disaster were also associated with at least one concern. Participants from the Kanto region were more concerned about radiation (2.08; 1.58-2.74) and food safety (1.30; 1.07-1.59), which demonstrate similar positive associations to participants from Tohoku where a disaster relief act was invoked (3.36; 2.25-5.01 about radiation, 1.49; 1.08-2.06 about food safety). Sectioning the populations by gender and other demographics will clarify prospective targets for interventions, allow for a better understanding of post-disaster concerns, and help communicate relevant information effectively.

  20. The leaded apron revisited: does it reduce gonadal radiation dose in dental radiology

    Energy Technology Data Exchange (ETDEWEB)

    Wood, R.E.; Harris, A.M.; van der Merwe, E.J.; Nortje, C.J. (Ontario Cancer Institute, Princess Margaret Hospital, Toronto (Canada))

    1991-05-01

    A tissue-equivalent anthropomorphic human phantom was used with a lithium fluoride thermoluminescent dosimetry system to evaluate the radiation absorbed dose to the ovarian and testicular region during dental radiologic procedures. Measurements were made with and without personal lead shielding devices consisting of thyroid collar and apron of 0.25 mm lead thickness equivalence. The radiation absorbed dose with or without lead shielding did not differ significantly from control dosimeters in vertex occlusal and periapical views (p greater than 0.05). Personal lead shielding devices did reduce gonadal dose in the case of accidental exposure (p less than 0.05). A leaded apron of 0.25 mm lead thickness equivalent was permeable to radiation in direct exposure testing.

  1. The leaded apron revisited: does it reduce gonadal radiation dose in dental radiology

    International Nuclear Information System (INIS)

    Wood, R.E.; Harris, A.M.; van der Merwe, E.J.; Nortje, C.J.

    1991-01-01

    A tissue-equivalent anthropomorphic human phantom was used with a lithium fluoride thermoluminescent dosimetry system to evaluate the radiation absorbed dose to the ovarian and testicular region during dental radiologic procedures. Measurements were made with and without personal lead shielding devices consisting of thyroid collar and apron of 0.25 mm lead thickness equivalence. The radiation absorbed dose with or without lead shielding did not differ significantly from control dosimeters in vertex occlusal and periapical views (p greater than 0.05). Personal lead shielding devices did reduce gonadal dose in the case of accidental exposure (p less than 0.05). A leaded apron of 0.25 mm lead thickness equivalent was permeable to radiation in direct exposure testing

  2. Potentials of ionizing radiation in reducing hazards to man and environment

    Energy Technology Data Exchange (ETDEWEB)

    Mullie, W C; Van Laerhoven, M J.A.M.; Kroes, R

    1991-07-01

    The main goal of the title study was to compare a relevant number of conventional processes and technologies for a range of uses with the application of ionizing radiation technology. Special emphasis is given to the hazardous effects of contemporary processes and chemicals on man and environment and to the potential role of the radiation processing technology, gamma irradiation in particular, in reducing these hazards. Based on their quantities and on (eco)toxicological criteria, four fields of application were identified a priori as potentially of interest for radiation processing. These fields of application are food preservation, sterilization and sanitization of pharmaceuticals and cosmetics, waste water and drinking water disinfection, and disinfection of sewage sludge and infectious hospital waste. Other fields of application as mentioned above are discussed in a more general matter. 12 figs., 31 tabs., 4 apps., refs.

  3. Effect of ionizing radiation on reducing the several inhibitors in codling moth Cydia pomonella (L.) medium

    International Nuclear Information System (INIS)

    Mohamad, F. A.

    2008-01-01

    The medium for Codling moth, Cydia pomonella (L) was sterilized using ionizing radiation (0, 5, 15 and 25 KGy) or heat (cooking for 40 minutes.). inhibitors were also added either on the top of the diet or by mixing it with the diet. The results showed that all Codling moth larvae in the ionizing radiation sterilized diet died before reaching the 4th larval instar. Results of using both radiation and cooking for sterilizing the diet gave variable results; those treated with 15 KGy gave significantly more moths with higher weight and more fecundity. The results also showed that increasing the amount of microbial inhibitors in diet negatively affected the number of produced moth and their biological characteristics. Consequently irradiation could be a mean for reducing the amount of chemical inhibitors added to the diet. (author)

  4. Measures taken by the building authorities in order to reduce radiation risks in buildings

    International Nuclear Information System (INIS)

    Tell, Wilhelm

    1980-01-01

    The Swedish radon commission has recommended that the risk of radiation and radon emission from the ground be considered when planning for new settlements, building materials with high radioactivity not be allowed for new buildings, and existing buildings with high levels of radioactivity be traced and improved. Maps of gamma radiation from the ground are being worked out showing areas with levels higher than 30 μR/h. Within such areas buildings should be planned taking the ultimate limits for new buildings into account. Building permits are granted for construction of new structures or extensive renovations if it can be shown that radiation levels within the buildings will be within legal limits: 70 Bq/m 3 for new buildings and 200 Bq/m 3 for existing ones. The radon commission has suggested that buildings with a radon daughter concentration exceeding 400 Bq/m 3 should be found and levels reduced to 200 Bq/m 3

  5. Analysis of technologies and experiences for reducing occupational radiation dose and study for applying to regulations

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Joo Hyun; Park, Moon Soo; Lee, Un Jang; Song, Jae Hyuk; Kim, Byeong Soo; Kim, Chong Uk [Seoul National Univ., Seoul (Korea, Republic of)

    2003-01-15

    To reduce Occupational Radiation Dose (ORD) effectively and enhance the radiological safety, the comprehensive assessment of the experiences to reduce ORD should be made by regulatory body as well as utilities. Hence, the objective of this study is to assess the experiences for reducing ORD from the regulatory viewpoint. With the research objective, the followings are performed in this research; analysis of occupational dose trends at domestic and foreign NPPs, identification of the effective technologies for reducing ORD, examination of the effects of the technologies for reducing ORD, derivation of the regulatory means for implementing he research results. From this study, the regulatory means for effective reduction of ORD are derived. Hence, the results can be utilized as a basic materials for ALARA requirements.

  6. Aspects of the quality of data from the Southern Great Plains (SGP) cloud and radiation testbed (CART) site broadband radiation sensors

    Energy Technology Data Exchange (ETDEWEB)

    Splitt, M.E. [Univ. of Oklahoma, Norman, OK (United States); Wesely, M.L. [Argonne National Lab., IL (United States)

    1996-04-01

    A systmatic evaluation of the performance of broadband radiometers at the Radiation Testbed (CART) site is needed to estimate the uncertainties of the irradiance observations. Here, net radiation observed with the net radiometer in the enrgy balance Bowen ratio station at the Central facility is compared with the net radiation computed as the sum of component irradiances recorded by nearby pyranameters and pyrgeometers. In addition, data obtained from the central facility pyranometers, pyrgeometers, and pyrheliometers are examined for April 1994, when intensive operations periods were being carried out. The data used in this study are from central facility radiometers in a solar and infrared observation station, and EBBR station, the so-called `BSRN` set of upward pointing radiometers, and a set of radiometers pointed down at the 25-m level of a 60-m tower.

  7. Solar radiation for buildings application: comparing reduced data set for mediterranean sites

    International Nuclear Information System (INIS)

    La Gennusa, M.; Rizzo, G.; Scaccianoce, G.; Sorrentino, G.

    2006-01-01

    A growing diffusion of computer programs for the thermal simulation of buildings is occurring in the last year; they allow the description of the thermal behaviour of buildings during the year, in order to verify their energy efficiencies and to suggest eventual improvements, even at the design stage. These thermal simulation programs generally need a complete input data set and among these, information particularly referring to the climatic conditions of the site where the building will be built-up. As it is well known, a climatic issue, particularly important for the thermal energy balance, is the solar radiation. In this work we have updated a short reference year of the solar radiation, more precisely the Monthly Average Day (MAD) for a town of the Southern Italy (Palermo), which shows climatic features similar to other places in the Mediterranean basin. In addition, we have compared the climatic data of the MAD (for the global and diffuse solar radiations) obtained from hourly measures for seven years, with those obtained both from geo-astronomical parameters and from the monthly average of the daily global solar radiation, which is commonly adopted on purposes. The comparison does suggest a particular caution in the choice of the method used for generating reduced data sets of the solar radiation for these mediterranean.(Author)

  8. Investigations on image improvement in radiodiagnosis under special consideration of reducing scattered radiation

    International Nuclear Information System (INIS)

    Becker, R.

    1976-10-01

    In the study, image improvement is proposed for scintiscanning, X-ray and neutron diagnosis as well as computer axial tomography. In order to reduce the scattered radiation, mainly two-dimensional radiation transport calculations are carried out, and the imaging properties are studied by simulation on a large computer. It was found, among other things, that in contrast to X-ray techniques, in diagnosis with fast neutrons the image quality can hardly be improved by screens for scattered radiation. Here the problem of scattered radiation can only be solved by using scanners with narrow beams. The new method of neutron diagnosis resulting from this is especially suited for representing structures behind bones or for the localization of bone tumors invisible to X-rays, but not for representing fatty tissue. For large depths of irradiation, the scattered radiation with neutron sources below 1 MeV gets so intensive that diagnosis becomes impossible. When fast neutrons are used are used, the method is applicable for computer axial tomography because of the narrow beams. (ORU) [de

  9. Guide to reducing radiation exposure to as low as reasonably achievable (ALARA)

    Energy Technology Data Exchange (ETDEWEB)

    Kathren, R.L.

    1980-04-01

    This document is designed to provide DOE contractor personnel with general guidance regarding programs and techniques to reduce radiation exposures to as low as reasonably achievable (ALARA). Thus it is directed towards a broad audience, and should have special relevance and interest for operating management as well as radiation protection personnel. It is well recognized that each contractor has needs specific and critical to its radiation protection program. Hence no single set of specific and detailed criteria can be set down as a prescription for achieving the ALARA goal. Rather, general guidance in the form of broad principles is given in order to acquaint management with ALARA needs and concepts. The purpose is to encourage maximum management support of the technical personnel responsible for carrying out day-to-day radiation protection activities. Although primarily written for management, this document also contains technical guidance of potential value to those directly involved in radiation protection activities. Again it should be stressed that what is provided is guidance, and is therefore not mandatory.

  10. Reducing the Harmful Effects of Infrared Radiation on the Skin Using Bicosomes Incorporating β-Carotene.

    Science.gov (United States)

    Fernández, Estibalitz; Fajarí, Lluís; Rodríguez, Gelen; Cócera, Mercedes; Moner, Verónica; Barbosa-Barros, Lucyanna; Kamma-Lorger, Christina S; de la Maza, Alfonso; López, Olga

    2016-01-01

    In this work the effect of infrared (IR) radiation, at temperatures between 25 and 30°C, on the formation of free radicals (FRs) in the skin is studied. Additionally, the influence of IR radiation at high temperatures in the degradation of skin collagen is evaluated. In both experiments the protective effect against IR radiation of phospholipid nanostructures (bicosomes) incorporating β-carotene (Bcb) is also evaluated. The formation of FRs in skin under IR exposure was measured near physiological temperatures (25-30°C) using 5,5-dimethyl-1-pyrroline-N-oxide spin trap and electron paramagnetic resonance (EPR) spectroscopy. The study of the collagen structure was performed by small-angle X-ray scattering using synchrotron radiation. EPR results showed an increase in the hydroxyl radical in the irradiated skin compared to the native skin. The skin collagen was degraded by IR exposure at high temperatures of approximately 65°C. The treatment with Bcb reduced the formation of FRs and kept the structure of collagen. The formation of FRs by IR radiation does not depend on the increase of skin temperature. The decrease of FRs and the preservation of collagen fibers in the skin treated with Bcb indicate the potential of this lipid system to protect skin under IR exposure. © 2016 S. Karger AG, Basel.

  11. Guide to reducing radiation exposure to as low as reasonably achievable (ALARA)

    International Nuclear Information System (INIS)

    Kathren, R.L.

    1980-04-01

    This document is designed to provide DOE contractor personnel with general guidance regarding programs and techniques to reduce radiation exposures to as low as reasonably achievable (ALARA). Thus it is directed towards a broad audience, and should have special relevance and interest for operating management as well as radiation protection personnel. It is well recognized that each contractor has needs specific and critical to its radiation protection program. Hence no single set of specific and detailed criteria can be set down as a prescription for achieving the ALARA goal. Rather, general guidance in the form of broad principles is given in order to acquaint management with ALARA needs and concepts. The purpose is to encourage maximum management support of the technical personnel responsible for carrying out day-to-day radiation protection activities. Although primarily written for management, this document also contains technical guidance of potential value to those directly involved in radiation protection activities. Again it should be stressed that what is provided is guidance, and is therefore not mandatory

  12. Estimation of potential evapotranspiration from extraterrestrial radiation, air temperature and humidity to assess future climate change effects on the vegetation of the Northern Great Plains, USA

    Science.gov (United States)

    King, David A.; Bachelet, Dominique M.; Symstad, Amy J.; Ferschweiler, Ken; Hobbins, Michael

    2014-01-01

    The potential evapotranspiration (PET) that would occur with unlimited plant access to water is a central driver of simulated plant growth in many ecological models. PET is influenced by solar and longwave radiation, temperature, wind speed, and humidity, but it is often modeled as a function of temperature alone. This approach can cause biases in projections of future climate impacts in part because it confounds the effects of warming due to increased greenhouse gases with that which would be caused by increased radiation from the sun. We developed an algorithm for linking PET to extraterrestrial solar radiation (incoming top-of atmosphere solar radiation), as well as temperature and atmospheric water vapor pressure, and incorporated this algorithm into the dynamic global vegetation model MC1. We tested the new algorithm for the Northern Great Plains, USA, whose remaining grasslands are threatened by continuing woody encroachment. Both the new and the standard temperature-dependent MC1 algorithm adequately simulated current PET, as compared to the more rigorous PenPan model of Rotstayn et al. (2006). However, compared to the standard algorithm, the new algorithm projected a much more gradual increase in PET over the 21st century for three contrasting future climates. This difference led to lower simulated drought effects and hence greater woody encroachment with the new algorithm, illustrating the importance of more rigorous calculations of PET in ecological models dealing with climate change.

  13. Viscoelastic property tuning for reducing noise radiated by switched-reluctance machines

    Science.gov (United States)

    Millithaler, Pierre; Dupont, Jean-Baptiste; Ouisse, Morvan; Sadoulet-Reboul, Émeline; Bouhaddi, Noureddine

    2017-10-01

    Switched-reluctance motors (SRM) present major acoustic drawbacks that hinder their use for electric vehicles in spite of widely-acknowledged robustness and low manufacturing costs. Unlike other types of electric machines, a SRM stator is completely encapsulated/potted with a viscoelastic resin. By taking advantage of the high damping capacity that a viscoelastic material has in certain temperature and frequency ranges, this article proposes a tuning methodology for reducing the noise emitted by a SRM in operation. After introducing the aspects the tuning process will focus on, the article details a concrete application consisting in computing representative electromagnetic excitations and then the structural response of the stator including equivalent radiated power levels. An optimised viscoelastic material is determined, with which the peak radiated levels are reduced up to 10 dB in comparison to the initial state. This methodology is implementable for concrete industrial applications as it only relies on common commercial finite-element solvers.

  14. Approach to reducing the effect of bone—coal power station on radiation environment

    Institute of Scientific and Technical Information of China (English)

    NIShi-Ying; GUPei-Long; 等

    2002-01-01

    The effect of two bone-coal power stations(6MWe) on environment was investigated within the scope of the dose contribution caused by various radionucildes in different ways.It is found that the best measures to reduce the effect of bone-coal power station on radiation environment include to select a fine boiler system and a comprehensive utilization of the bone-coal cinder(BCC),soot and ash in the catchers.

  15. Approach to reducing the effect of bone-coal power station on radiation environment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The effect of two bone-coal power stations (6 MWe) on environment wasinvestigated within the scope of the dose contribution caused by various radionucildes in different ways. It is found that the best measures to reduce the effect of bone-coal power station on radiation environment include to select a fine boiler system and a comprehensive utilization of the bone-coal cinder (BCC), soot and ash in the catchers.

  16. New image-processing and noise-reduction software reduces radiation dose during complex endovascular procedures.

    Science.gov (United States)

    Kirkwood, Melissa L; Guild, Jeffrey B; Arbique, Gary M; Tsai, Shirling; Modrall, J Gregory; Anderson, Jon A; Rectenwald, John; Timaran, Carlos

    2016-11-01

    procedures with and without Clarity were not significantly different. For all cases, procedure radiation dose to the patient and the primary and assistant operators were significantly decreased in the Clarity group by 60% compared with the non-Clarity group. By procedure type, fluorography dose rates decreased from 44% for fenestrated endovascular repair and up to 70% with lower extremity interventions. Fluoroscopy dose rates also significantly decreased, from about 37% to 47%, depending on procedure type. The AlluraClarity system reduces the patient and primary operator's radiation dose by more than half during CEPs. This feature appears to be an effective tool in lowering the radiation dose while maintaining image quality. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  17. Interventions to prevent skin cancer by reducing exposure to ultraviolet radiation: a systematic review.

    Science.gov (United States)

    Saraiya, Mona; Glanz, Karen; Briss, Peter A; Nichols, Phyllis; White, Cornelia; Das, Debjani; Smith, S Jay; Tannor, Bernice; Hutchinson, Angela B; Wilson, Katherine M; Gandhi, Nisha; Lee, Nancy C; Rimer, Barbara; Coates, Ralph C; Kerner, Jon F; Hiatt, Robert A; Buffler, Patricia; Rochester, Phyllis

    2004-12-01

    The relationship between skin cancer and ultraviolet radiation is well established. Behaviors such as seeking shade, avoiding sun exposure during peak hours of radiation, wearing protective clothing, or some combination of these behaviors can provide protection. Sunscreen use alone is not considered an adequate protection against ultraviolet radiation. This report presents the results of systematic reviews of effectiveness, applicability, other harms or benefits, economic evaluations, and barriers to use of selected interventions to prevent skin cancer by reducing exposure to ultraviolet radiation. The Task Force on Community Preventive Services found that education and policy approaches to increasing sun-protective behaviors were effective when implemented in primary schools and in recreational or tourism settings, but found insufficient evidence to determine effectiveness when implemented in other settings, such as child care centers, secondary schools and colleges, and occupational settings. They also found insufficient evidence to determine the effectiveness of interventions oriented to healthcare settings and providers, media campaigns alone, interventions oriented to parents or caregivers of children, and community-wide multicomponent interventions. The report also provides suggestions for areas for future research.

  18. Radiation safety education reduces the incidence of adult fingers on neonatal chest radiographs

    International Nuclear Information System (INIS)

    Sahota, N; Burbridge, B E; Duncan, M D

    2014-01-01

    A previous audit revealed a high frequency of adult fingers visualised on neonatal intensive care unit (NICU) chest radiographs—representing an example of inappropriate occupational radiation exposure. Radiation safety education was provided to staff and we hypothesised that the education would reduce the frequency of adult fingers visualised on NICU chest radiographs. Two cross-sectional samples taken before and after the administration of the education were compared. We examined fingers visualised directly in the beam, fingers in the direct beam but eliminated by technologists editing the image, and fingers under the cones of the portable x-ray machine. There was a 46.2% reduction in fingers directly in the beam, 50.0% reduction in fingers directly in the beam but cropped out, and 68.4% reduction in fingers in the coned area. There was a 57.1% overall reduction in adult fingers visualised, which was statistically significant (Z value − 7.48, P < 0.0001). This study supports radiation safety education in minimising inappropriate occupational radiation exposure. (paper)

  19. Does Ad Hoc Coronary Intervention Reduce Radiation Exposure? – Analysis of 568 Patients

    Energy Technology Data Exchange (ETDEWEB)

    Truffa, Márcio A. M., E-mail: marciotruffa@yahoo.com.br; Alves, Gustavo M.P.; Bernardi, Fernando; Esteves Filho, Antonio; Ribeiro, Expedito; Galon, Micheli Z.; Spadaro, André; Kajita, Luiz J.; Arrieta, Raul; Lemos, Pedro A. [Instituto do Coração - Hospital das Clínicas - Faculdade de Medicina da Universidade de São Paulo (USP), São Paulo, SP (Brazil)

    2015-11-15

    Advantages and disadvantages of ad hoc percutaneous coronary intervention have been described. However little is known about the radiation exposure of that procedure as compared with the staged intervention. To compare the radiation dose of the ad hoc percutaneous coronary intervention with that of the staged procedure The dose-area product and total Kerma were measured, and the doses of the diagnostic and therapeutic procedures were added. In addition, total fluoroscopic time and number of acquisitions were evaluated. A total of 568 consecutive patients were treated with ad hoc percutaneous coronary intervention (n = 320) or staged percutaneous coronary intervention (n = 248). On admission, the ad hoc group had less hypertension (74.1% vs 81.9%; p = 0.035), dyslipidemia (57.8% vs. 67.7%; p = 0.02) and three-vessel disease (38.8% vs. 50.4%; p = 0.015). The ad hoc group was exposed to significantly lower radiation doses, even after baseline characteristic adjustment between both groups. The ad hoc group was exposed to a total dose-area product of 119.7 ± 70.7 Gycm{sup 2}, while the staged group, to 139.2 ± 75.3 Gycm{sup 2} (p < 0.001). Ad hoc percutaneous coronary intervention reduced radiation exposure as compared with diagnostic and therapeutic procedures performed at two separate times.

  20. CFD simulations and reduced order modeling of a refrigerator compartment including radiation effects

    International Nuclear Information System (INIS)

    Bayer, Ozgur; Oskay, Ruknettin; Paksoy, Akin; Aradag, Selin

    2013-01-01

    Highlights: ► Free convection in a refrigerator is simulated including radiation effects. ► Heat rates are affected drastically when radiation effects are considered. ► 95% of the flow energy can be represented by using one spatial POD mode. - Abstract: Considering the engineering problem of natural convection in domestic refrigerator applications, this study aims to simulate the fluid flow and temperature distribution in a single commercial refrigerator compartment by using the experimentally determined temperature values as the specified constant wall temperature boundary conditions. The free convection in refrigerator applications is evaluated as a three-dimensional (3D), turbulent, transient and coupled non-linear flow problem. Radiation heat transfer mode is also included in the analysis. According to the results, taking radiation effects into consideration does not change the temperature distribution inside the refrigerator significantly; however the heat rates are affected drastically. The flow inside the compartment is further analyzed with a reduced order modeling method called Proper Orthogonal Decomposition (POD) and the energy contents of several spatial and temporal modes that exist in the flow are examined. The results show that approximately 95% of all the flow energy can be represented by only using one spatial mode

  1. Does Ad Hoc Coronary Intervention Reduce Radiation Exposure? – Analysis of 568 Patients

    International Nuclear Information System (INIS)

    Truffa, Márcio A. M.; Alves, Gustavo M.P.; Bernardi, Fernando; Esteves Filho, Antonio; Ribeiro, Expedito; Galon, Micheli Z.; Spadaro, André; Kajita, Luiz J.; Arrieta, Raul; Lemos, Pedro A.

    2015-01-01

    Advantages and disadvantages of ad hoc percutaneous coronary intervention have been described. However little is known about the radiation exposure of that procedure as compared with the staged intervention. To compare the radiation dose of the ad hoc percutaneous coronary intervention with that of the staged procedure The dose-area product and total Kerma were measured, and the doses of the diagnostic and therapeutic procedures were added. In addition, total fluoroscopic time and number of acquisitions were evaluated. A total of 568 consecutive patients were treated with ad hoc percutaneous coronary intervention (n = 320) or staged percutaneous coronary intervention (n = 248). On admission, the ad hoc group had less hypertension (74.1% vs 81.9%; p = 0.035), dyslipidemia (57.8% vs. 67.7%; p = 0.02) and three-vessel disease (38.8% vs. 50.4%; p = 0.015). The ad hoc group was exposed to significantly lower radiation doses, even after baseline characteristic adjustment between both groups. The ad hoc group was exposed to a total dose-area product of 119.7 ± 70.7 Gycm 2 , while the staged group, to 139.2 ± 75.3 Gycm 2 (p < 0.001). Ad hoc percutaneous coronary intervention reduced radiation exposure as compared with diagnostic and therapeutic procedures performed at two separate times

  2. Assessment of the Potential to Reduce Emissions from Road Transportation, Notably NOx, Through the Use of Alternative Vehicles and Fuels in the Great Smoky Mountains Region; TOPICAL

    International Nuclear Information System (INIS)

    Sheffield, J.

    2001-01-01

    Air pollution is a serious problem in the region of the Great Smoky Mountains. The U.S. Environmental Protection Agency (EPA) may designate non-attainment areas by 2003 for ozone. Pollutants include nitrogen oxides (NOx), sulfur dioxide (SO(sub 2)), carbon monoxide (CO), volatile organic compounds (VOCs), lead, and particulate matter (PM), which are health hazards, damage the environment, and limit visibility. The main contributors to this pollution are industry, transportation, and utilities. Reductions from all contributors are needed to correct this problem. While improvements are projected in each sector over the next decades, the May 2000 Interim Report issued by the Southern Appalachian Mountains Initiative (SAMI) suggests that the percentage of NOx emissions from transportation may increase. The conclusions are: (1) It is essential to consider the entire fuel cycle in assessing the benefits, or disadvantages, of an alternative fuel option, i.e., feedstock and fuel production, in addition to vehicle operation; (2) Many improvements to the energy efficiency of a particular vehicle and engine combination will also reduce emissions by reducing fuel use, e.g., engine efficiency, reduced weight, drag and tire friction, and regenerative braking; (3) In reducing emissions it will be important to install the infrastructure to provide the improved fuels, support the maintenance of advanced vehicles, and provide emissions testing of both local vehicles and those from out of state; (4) Public transit systems using lower emission vehicles can play an important role in reducing emissions per passenger mile by carrying passengers more efficiently, particularly in congested areas. However, analysis is required for each situation; (5) Any reduction in emissions will be welcome, but the problems of air pollution in our region will not be solved by a few modest improvements. Substantial reductions in emissions of key pollutants are required both in East Tennessee and in

  3. The Effect of Reduced Water Availability in the Great Ruaha River on the Vulnerable Common Hippopotamus in the Ruaha National Park, Tanzania.

    Directory of Open Access Journals (Sweden)

    Claudia Stommel

    Full Text Available In semi-arid environments, 'permanent' rivers are essential sources of surface water for wildlife during 'dry' seasons when rainfall is limited or absent, particularly for species whose resilience to water scarcity is low. The hippopotamus (Hippopotamus amphibius requires submersion in water to aid thermoregulation and prevent skin damage by solar radiation; the largest threat to its viability are human alterations of aquatic habitats. In the Ruaha National Park (NP, Tanzania, the Great Ruaha River (GRR is the main source of surface water for wildlife during the dry season. Recent, large-scale water extraction from the GRR by people upstream of Ruaha NP is thought to be responsible for a profound decrease in dry season water-flow and the absence of surface water along large sections of the river inside the NP. We investigated the impact of decreased water flow on daytime hippo distribution using regular censuses at monitoring locations, transects and camera trap records along a 104km section of the GRR within the Ruaha NP during two dry seasons. The minimum number of hippos per monitoring location increased with the expanse of surface water as the dry seasons progressed, and was not affected by water quality. Hippo distribution significantly changed throughout the dry season, leading to the accumulation of large numbers in very few locations. If surface water loss from the GRR continues to increase in future years, this will have serious implications for the hippo population and other water dependent species in Ruaha NP.

  4. Radiation preservation with reduced nitrites of bacon and other cured meats - a review

    International Nuclear Information System (INIS)

    Singh, H.

    1987-01-01

    The main problem caused by nitrite as a preservative is the formation of carcinogenic nitrosamines in bacon and other cured meats. This has led to a search for alternatives to the use of nitrite. Irradiation with reduced level of nitrite is a promising alternative to the use of current levels of nitrite. Radurization (radiation pasteurization) of bacon containing 20 to to 40 mg/kg of nitrite in evacuated packages, irradiated and stored at 4 degrees C, gives a product with good organoleptic qualities and extended shelf life of > 80 days vs. < days 30 days for the conventionally treated bacon. Radappertization (radiation sterilization) of bacon containing 20 mg/kg of nitrite at a dose of about 30 kGy, irradiated at -20 degrees or lower in evacuated packages, results in a product that is shelf stable for months to years at room temperature (∼ 25 degrees C). It has organoleptic properties comparable to commercial bacon in terms of color, flavor, odor and texture. Irradiation also reduces the nitrite and preformed nitrosamines present in bacon. Lower levels of nitrosamines are formed on cooking irradiated bacon containing presently used commercial levels of nitrite (120-150 mg/kg) and the levels of nitrosamines become negligible with 20 mg/kg of nitrite. Various aspects of preservation of bacon and other cured meats are reviewed in this report with emphasis on radiation processing. 357 refs

  5. Reduced anthropogenic aerosol radiative forcing caused by biogenic new particle formation

    Science.gov (United States)

    Gordon, Hamish; Sengupta, Kamalika; Rap, Alexandru; Duplissy, Jonathan; Frege, Carla; Williamson, Christina; Heinritzi, Martin; Simon, Mario; Yan, Chao; Almeida, João; Tröstl, Jasmin; Nieminen, Tuomo; Ortega, Ismael K.; Wagner, Robert; Dunne, Eimear M.; Adamov, Alexey; Amorim, Antonio; Bernhammer, Anne-Kathrin; Bianchi, Federico; Breitenlechner, Martin; Brilke, Sophia; Chen, Xuemeng; Craven, Jill S.; Dias, Antonio; Ehrhart, Sebastian; Fischer, Lukas; Flagan, Richard C.; Franchin, Alessandro; Fuchs, Claudia; Guida, Roberto; Hakala, Jani; Hoyle, Christopher R.; Jokinen, Tuija; Junninen, Heikki; Kangasluoma, Juha; Kim, Jaeseok; Kirkby, Jasper; Krapf, Manuel; Kürten, Andreas; Laaksonen, Ari; Lehtipalo, Katrianne; Makhmutov, Vladimir; Mathot, Serge; Molteni, Ugo; Monks, Sarah A.; Onnela, Antti; Peräkylä, Otso; Piel, Felix; Petäjä, Tuukka; Praplan, Arnaud P.; Pringle, Kirsty J.; Richards, Nigel A. D.; Rissanen, Matti P.; Rondo, Linda; Sarnela, Nina; Schobesberger, Siegfried; Scott, Catherine E.; Seinfeld, John H.; Sharma, Sangeeta; Sipilä, Mikko; Steiner, Gerhard; Stozhkov, Yuri; Stratmann, Frank; Tomé, Antonio; Virtanen, Annele; Vogel, Alexander Lucas; Wagner, Andrea C.; Wagner, Paul E.; Weingartner, Ernest; Wimmer, Daniela; Winkler, Paul M.; Ye, Penglin; Zhang, Xuan; Hansel, Armin; Dommen, Josef; Donahue, Neil M.; Worsnop, Douglas R.; Baltensperger, Urs; Kulmala, Markku; Curtius, Joachim; Carslaw, Kenneth S.

    2016-10-01

    The magnitude of aerosol radiative forcing caused by anthropogenic emissions depends on the baseline state of the atmosphere under pristine preindustrial conditions. Measurements show that particle formation in atmospheric conditions can occur solely from biogenic vapors. Here, we evaluate the potential effect of this source of particles on preindustrial cloud condensation nuclei (CCN) concentrations and aerosol-cloud radiative forcing over the industrial period. Model simulations show that the pure biogenic particle formation mechanism has a much larger relative effect on CCN concentrations in the preindustrial atmosphere than in the present atmosphere because of the lower aerosol concentrations. Consequently, preindustrial cloud albedo is increased more than under present day conditions, and therefore the cooling forcing of anthropogenic aerosols is reduced. The mechanism increases CCN concentrations by 20-100% over a large fraction of the preindustrial lower atmosphere, and the magnitude of annual global mean radiative forcing caused by changes of cloud albedo since 1750 is reduced by 0.22 W m-2 (27%) to -0.60 W m-2. Model uncertainties, relatively slow formation rates, and limited available ambient measurements make it difficult to establish the significance of a mechanism that has its dominant effect under preindustrial conditions. Our simulations predict more particle formation in the Amazon than is observed. However, the first observation of pure organic nucleation has now been reported for the free troposphere. Given the potentially significant effect on anthropogenic forcing, effort should be made to better understand such naturally driven aerosol processes.

  6. Drinking beer reduces radiation-induced chromosome aberrations in human lymphocytes

    International Nuclear Information System (INIS)

    Monobe, Manami

    2002-01-01

    We here investigated and reported the effects of beer drinking on radiation-induced chromosome aberrations in blood lymphocytes. Human blood that was collected either before or after drinking a 700 ml beer was in vitro irradiated with 200 kVp X rays or 50 keV/μm carbon ions. The relation between the radiation dose and the aberration frequencies (fragments and dicentrics) was significantly (P<0.05) lower for lymphocytes collected 3 h after beer drinking than those before drinking. Fitting the dose response to a linear quadratic model showed that the alpha term of carbon ions was significantly (P<0.05) decreased by beer drinking. A decrease of dicentric formation was detected as early as 0.5 h after beer drinking, and lasted not shorter than 4.5 h. The mitotic index of lymphocytes was higher after beer drinking than before, indicating that a division delay would not be responsible for the low aberrations induced by beer drinking. An in vitro treatment of normal lymphocytes with 0.1 M ethanol, which corresponded to a concentration of 6-times higher than the maximum ethanol concentration in the blood after beer drinking, reduced the dicentric formation caused by X-ray irradiation, but not by carbon-ion irradiation. The beer-induced reduction of dicentric formation was not affected by serum. It is concluded that beer could contain non-ethanol elements that reduce the chromosome damage of lymphocytes induced by high-LET radiation. (author)

  7. Microdosimetric constraints on specific adaptation mechanisms to reduce DNA damage caused by ionising radiation

    International Nuclear Information System (INIS)

    Burkart, W.; Heusser, P.; Vijayalaxmi

    1990-01-01

    The protective effect of pre-exposure of lymphocytes to ionising radiation indicates the presence of 'adaptive repair' in mammalian cells. Microdosimetric considerations, however, raise some doubts on the advantage of such a cellular mechanism for specifically reducing the radiation damage caused by environmental exposures. Contrary to most chemicals which endanger the integrity of the mammalian genome, the local dose and dose rate from ionising radiation at the cellular level remain quite high, even at lowest exposures. A single electron or alpha particle passing through a cell nucleus already yields nuclear doses of up to about 3 mGy and 400 mGy, respectively. Macroscopic doses below these nuclear doses from a single event will only reduce the fraction of cell nuclei encountering the passage of a particle but not the dose or dose rate in the affected volume. At environmental doses in the range of 1 to 5 mGy per annum, the time between two consecutive hits in a specific cell nucleus is in the range of months to years. Very low concentrations of bleomycin, a drug with high affinity to DNA, also triggers an adaptive response. This points to a more general stress response mechanism which may benefit the cell even at environmental levels of radioactivity, e.g. by protecting the integrity of DNA from attacks by chemicals, by endogenous radicals, by acids from anoxia, etc. (author)

  8. Reduced anthropogenic aerosol radiative forcing caused by biogenic new particle formation.

    Science.gov (United States)

    Gordon, Hamish; Sengupta, Kamalika; Rap, Alexandru; Duplissy, Jonathan; Frege, Carla; Williamson, Christina; Heinritzi, Martin; Simon, Mario; Yan, Chao; Almeida, João; Tröstl, Jasmin; Nieminen, Tuomo; Ortega, Ismael K; Wagner, Robert; Dunne, Eimear M; Adamov, Alexey; Amorim, Antonio; Bernhammer, Anne-Kathrin; Bianchi, Federico; Breitenlechner, Martin; Brilke, Sophia; Chen, Xuemeng; Craven, Jill S; Dias, Antonio; Ehrhart, Sebastian; Fischer, Lukas; Flagan, Richard C; Franchin, Alessandro; Fuchs, Claudia; Guida, Roberto; Hakala, Jani; Hoyle, Christopher R; Jokinen, Tuija; Junninen, Heikki; Kangasluoma, Juha; Kim, Jaeseok; Kirkby, Jasper; Krapf, Manuel; Kürten, Andreas; Laaksonen, Ari; Lehtipalo, Katrianne; Makhmutov, Vladimir; Mathot, Serge; Molteni, Ugo; Monks, Sarah A; Onnela, Antti; Peräkylä, Otso; Piel, Felix; Petäjä, Tuukka; Praplan, Arnaud P; Pringle, Kirsty J; Richards, Nigel A D; Rissanen, Matti P; Rondo, Linda; Sarnela, Nina; Schobesberger, Siegfried; Scott, Catherine E; Seinfeld, John H; Sharma, Sangeeta; Sipilä, Mikko; Steiner, Gerhard; Stozhkov, Yuri; Stratmann, Frank; Tomé, Antonio; Virtanen, Annele; Vogel, Alexander Lucas; Wagner, Andrea C; Wagner, Paul E; Weingartner, Ernest; Wimmer, Daniela; Winkler, Paul M; Ye, Penglin; Zhang, Xuan; Hansel, Armin; Dommen, Josef; Donahue, Neil M; Worsnop, Douglas R; Baltensperger, Urs; Kulmala, Markku; Curtius, Joachim; Carslaw, Kenneth S

    2016-10-25

    The magnitude of aerosol radiative forcing caused by anthropogenic emissions depends on the baseline state of the atmosphere under pristine preindustrial conditions. Measurements show that particle formation in atmospheric conditions can occur solely from biogenic vapors. Here, we evaluate the potential effect of this source of particles on preindustrial cloud condensation nuclei (CCN) concentrations and aerosol-cloud radiative forcing over the industrial period. Model simulations show that the pure biogenic particle formation mechanism has a much larger relative effect on CCN concentrations in the preindustrial atmosphere than in the present atmosphere because of the lower aerosol concentrations. Consequently, preindustrial cloud albedo is increased more than under present day conditions, and therefore the cooling forcing of anthropogenic aerosols is reduced. The mechanism increases CCN concentrations by 20-100% over a large fraction of the preindustrial lower atmosphere, and the magnitude of annual global mean radiative forcing caused by changes of cloud albedo since 1750 is reduced by [Formula: see text] (27%) to [Formula: see text] Model uncertainties, relatively slow formation rates, and limited available ambient measurements make it difficult to establish the significance of a mechanism that has its dominant effect under preindustrial conditions. Our simulations predict more particle formation in the Amazon than is observed. However, the first observation of pure organic nucleation has now been reported for the free troposphere. Given the potentially significant effect on anthropogenic forcing, effort should be made to better understand such naturally driven aerosol processes.

  9. The Great Wall in the CfA survey - Its origin and imprint on the microwave background radiation

    Science.gov (United States)

    Atrio-Barandela, F.; Kashlinsky, A.

    1992-01-01

    The paper models the evolution of the Great Wall (GW) after recombination and the influence of its time-dependent gravitational potential on the MBR. It is shown that within the framework of the Zel'dovich approximation the (pre)GW region can be treated as an ellipsoid. The GW is approximated as an oblate ellipsoid that started at recombination with an almost spherical shape, but with initial density contrast, delta-i, much smaller than it had to be in the spherical model in order to reach the observed density contrast of beta-f of 5. The resultant delta-i is compatible with the rms value of delta-rho/rho on the GW scale at recombination for models with the n less than 0 power spectrum of the primordial density field. It is shown that the time-dependent potential of the GW will induce a detectable fluctuation in MBR. The possibility of similar structures located at higher redshifts producing measurable and perhaps dominant statistical MBR anisotropies by this effect is also discussed.

  10. Temporary reduction of radiation does not permanently reduce flavonoid glycosides and phenolic acids in red lettuce.

    Science.gov (United States)

    Becker, Christine; Kläring, Hans-Peter; Kroh, Lothar W; Krumbein, Angelika

    2013-11-01

    Applying transparent daytime screens in greenhouses in cool seasons reduces the amount of energy needed for heating, but also the solar radiation available for crops. This can reduce yield and product quality of leafy vegetables because of constrained photosynthesis and altered biosynthesis. To study this, we cultivated five-week old red leaf lettuce (Lactuca sativa L.) for four weeks in growth chambers under a photosynthetic photon flux density (PPFD) of 225 and 410 μmol m(-2) s(-1), respectively. Some plants were exchanged between radiation intensities after two weeks. We investigated the concentration of five flavonoid glycosides, three caffeic acid derivatives, reducing sugars as well as plant growth. Remarkably, no significant influence of radiation intensity on the concentration of phenolic acids or anthocyanin glycosides was observed. In contrast, quercetin and luteolin glycoside concentration was between 14 and 34% lower in plants growing under lower compared to higher PPFD. Already after two weeks of cultivation, plants grown under lower PPFD contained less quercetin and luteolin glycosides but they completely compensated if subsequently transferred to higher PPFD until harvest. Hence, marketable lettuce heads which experienced temporary shading followed by an unshaded phase did not contain lower concentrations of flavonoid glycosides or phenolic acids. Also, there was no reduction of head mass in this variant. Our results suggest that saving energy in early growth stages is feasible without losses in yield or health promoting phenolic substances. In addition, there was a close correlation between the concentration of reducing sugars and some flavonoid glycosides, indicating a close metabolic connection between their biosynthesis and the availability of carbohydrates. Copyright © 2013 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

  11. Who was concerned about radiation, food safety, and natural disasters after the great East Japan earthquake and Fukushima catastrophe? A nationwide cross-sectional survey in 2012.

    Directory of Open Access Journals (Sweden)

    Takashi Sugimoto

    Full Text Available BACKGROUND: Disaster-related concerns by sub-populations have not been clarified after the great East Japan earthquake and the Fukushima nuclear power plant incidents. This paper assesses who was concerned about radiation, food safety, and natural disasters among the general population in order to buffer such concerns effectively. METHODS: The hypothesis that women, parents, and family caregivers were most concerned about radiation, food safety, and natural disaster was tested using a varying-intercept multivariable logistic regression with 5809 responses from a nationwide cross-sectional survey random-sampled in March 2012. RESULTS: Many people were at least occasionally concerned about radiation (53.5%, food safety (47.3%, and about natural disaster (69.5%. Women were more concerned than men about radiation (OR = 1.67; 95% CI = 1.35-2.06, food safety (1.70; 1.38-2.10, and natural disasters (1.74; 1.39-2.19. Parents and family care needs were not significant. Married couples were more concerned about radiation (1.53; 1.33-1.77, food safety (1.38; 1.20-1.59, and natural disasters (1.30; 1.12-1.52. Age, child-cohabitation, college-completion, retirement status, homemaker status, and the house-damage certificate of the last disaster were also associated with at least one concern. Participants from the Kanto region were more concerned about radiation (2.08; 1.58-2.74 and food safety (1.30; 1.07-1.59, which demonstrate similar positive associations to participants from Tohoku where a disaster relief act was invoked (3.36; 2.25-5.01 about radiation, 1.49; 1.08-2.06 about food safety. CONCLUSIONS: Sectioning the populations by gender and other demographics will clarify prospective targets for interventions, allow for a better understanding of post-disaster concerns, and help communicate relevant information effectively.

  12. Ambient UV-B radiation reduces PSII performance and net photosynthesis in high Arctic Salix arctica

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Mikkelsen, Teis Nørgaard; Ro-Poulsen, Helge

    2011-01-01

    Ambient ultraviolet-B (UV-B) radiation potentially impacts the photosynthetic performance of high Arctic plants. We conducted an UV-B exclusion experiment in a dwarf shrub heath in NE Greenland (74°N), with open control, filter control, UV-B filtering and UV-AB filtering, all in combination......, nitrogen and UV-B absorbing compounds. Compared to a 60% reduced UV-B irradiance, the ambient solar UV-B reduced net photosynthesis in Salix arctica leaves fixed in the 45° position which exposed leaves to maximum natural irradiance. Also a reduced Calvin Cycle capacity was found, i.e. the maximum rate...... across position in the vegetation. These findings add to the evidence that the ambient solar UV-B currently is a significant stress factor for plants in high Arctic Greenland....

  13. Radiation effects on low cycle fatigue properties of reduced activation ferritic/martensitic steels

    International Nuclear Information System (INIS)

    Hirose, T.; Tanigawa, H.; Ando, M.; Kohyama, A.; Katoh, Y.; Narui, M.

    2002-01-01

    The reduced activation ferritic/martensitic steel, RAFs F82H IEA heat has been fatigue-tested at ambient temperature under diametral strain controlled conditions. In order to evaluate the effects of radiation damage and transmutation damage on fatigue characteristics, post-neutron irradiation and post-helium ion implantation fatigue tests were carried out. Fracture surfaces and fatigue crack initiation on the specimen surface were observed by SEM. Low-temperature irradiation caused an increase in stress amplitude and a reduction in fatigue lifetime corresponding to radiation hardening and loss of ductility. Neutron irradiated samples showed brittle fracture surface, and it was significant for large strain tests. On the other hand, helium implantation caused delay of cyclic softening. However, brittle crack initiation and propagation did not depend on the helium concentration profiles

  14. NPP physical protection and information security as necessary conditions for reducing nuclear and radiation accident risks

    International Nuclear Information System (INIS)

    Pogosov, O.Yu.; Derevyanko, O.V.

    2017-01-01

    The paper focuses on the fact that nuclear failures and incidents can lead to radioactive contamination of NPP premises. Nuclear and radiation hazard may be caused by malefactors in technological processes when applying computers or inadequate control in case of insufficient level of information security.The researchers performed analysis of factors for reducing risks of nuclear and radiation accidents at NPPs considering specific conditions related to information security of NPP physical protection systems. The paper considers connection of heterogeneous factors that may increase the risk of NPP accidents, possibilities and ways to improve adequate modelling of security of information with limited access directly related to the functioning of automated set of engineering and technical means for NPP physical protection. Within the overall Hutchinson formalization, it is proposed to include additional functional dependencies on indicators specific for NPPs into analysis algorithms.

  15. Moderate solar geoengineering greatly reduces the largest changes in climate whilst modestly increasing the changes in climate over a small fraction of the Earth

    Science.gov (United States)

    Irvine, P. J.; Keith, D.; He, J.; Vecchi, G.; Horowitz, L. W.

    2017-12-01

    Whilst solar geoengineering reduces global temperature it cannot perfectly offset the climate effects of elevated CO2 concentrations. Solar geoengineering has been shown to have a greater effect on the global hydrological cycle than CO2 and substantial differences in regional precipitation relative to a scenario without elevated CO2­ concentrations have been noted. In this study we evaluate a moderate scenario of solar geoengineering, one which offsets 50% of the forcing from elevated CO2 concentrations, using a 25 Km resolution global climate model and verify these results using the Geoengineering model Intercomparison project ensemble. We calculate the fraction of regions that would be better or worse off after solar geoengineering deployment, defining those which see greater absolute change as worse off and vice versa. We find that 51% of the land area would be statistically significantly better off for precipitation, 33% for Precipitation minus evaporation (P-E), and that less than 3% would be worse off for precipitation, and 1% for P-E. We find that the fraction of the land area experiencing the largest changes in climate, defined as the upper quartile of the CO2 minus control anomaly, is greatly reduced for precipitation, P-E and 5-day maximum precipitation, and eliminated for mean and max annual temperature. The regions which are made worse off in precipitation or P-E by solar geoengineering typically saw relatively little to no CO2 induced climate change and see relatively little to moderate change in the solar geoengineering scenario. There is little overlap between the regions made worse off in terms of precipitation and P-E. In fact, whilst precipitation is reduced in almost all regions made worse off by solar geoengineering, P-E is increased in the majority of regions made worse off. Overall, we find that for each variable considered solar geoengineering greatly reduces the fraction of the world experiencing relatively large change and that those

  16. Ghrelin may reduce radiation-induced mucositis and anorexia in head-neck cancer.

    Science.gov (United States)

    Guney, Yildiz; Ozel Turkcu, Ummuhani; Hicsonmez, Ayse; Nalca Andrieu, Meltem; Kurtman, Cengiz

    2007-01-01

    Body weight loss is common in cancer patients, and is often associated with poor prognosis, it greatly impairs quality of life (QOL). Radiation therapy (RT) is used in head and neck cancers (HNC) either as a primary treatment or as an adjuvant therapy to surgery. Patients with HNC are most susceptible to malnutrition especially due to anorexia, which is aggravated by RT. Multiple pro-inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-1beta (IL-1beta), interferon (IFN)-gamma and tumor necrosis factor-alpha(TNF-alpha), have been all associated with the development of both anorexia and oral mucositis. Radiation-induced mucositis occurs in almost all patients, who are treated for HNC, it could also cause weight loss. Ghrelin is a novel 28-amino acid peptide, which up-regulates body weight through appetite control, increase food intake, down-regulate energy expenditure and induces adiposity. Furthermore, ghrelin inhibits pro-inflammatory cytokines such as IL-1alpha, IL-1beta, TNF-alpha which may cause oral mucositis and aneroxia, which are the results of weight loss. Thus weight loss during RT is an early indicator of nutritional decline, we propose that recombinant ghrelin used prophylactically could be useful as an appetite stimulant; and preventive of mucositis because of its anti-inflammatory effect, it might help patients maintain weight over the course of curative RT of the HNC and can improve specific aspects of QOL. This issue warrants further studies.

  17. Nicotinamide Phosphoribosyltransferase Upregulation by Phenylephrine Reduces Radiation Injury in Submandibular Gland

    International Nuclear Information System (INIS)

    Xiang, Bin; Han, Lichi; Wang, Xinyue; Tang, Ling; Li, Kailiang; Li, Xiuxiu; Zhao, Xibo; Xia, Miaomiao; Zhou, Xixi; Zhang, Fuyin; Liu, Ke Jian

    2016-01-01

    Purpose: Radiation therapy for head and neck cancer commonly leads to radiation sialadenitis. Emerging evidence has indicated that phenylephrine pretreatment reduces radiosensitivity in the salivary gland; however, the underlying cytoprotective mechanism remains unclear. Nicotinamide phosphoribosyltransferase (NAMPT) is not only a key enzyme for the nicotinamide adenine dinucleotide salvage pathway, but also a cytokine participating in cell survival, metabolism, and longevity, with a broad effect on cellular functions in physiology and pathology. However, the regulatory events of NAMPT in response to the irradiated salivary gland are unknown. Methods and Materials: The cell viability of primary cultured submandibular gland cells was determined using the PrestoBlue assay. NAMPT expression was measured using reverse transcriptase polymerase chain reaction and Western blotting in vitro and in vivo. Silent information regulator 1 (SIRT1) and phosphorylated Akt protein levels were examined by Western blotting. The cellular locations of NAMPT and SIRT1 were detected by immunohistochemistry. NAMPT promoter activity was assessed using the luciferase reporter gene assay. Results: NAMPT was mainly distributed in the cytoplasm of granular convoluted tubule cells and ductal cells in normal submandibular glands. mRNA and protein expression of NAMPT was downregulated after radiation but upregulated with phenylephrine pretreatment both in vivo and in vitro. Moreover, the protein expression of phosphorylated Akt and SIRT1 was decreased in irradiated glands, and phenylephrine pretreatment restored the expression of both. SIRT1 was mainly located in the cell nucleus and cytoplasm in the normal submandibular gland. Phenylephrine dramatically enhanced the expression of SIRT1, which was significantly reduced by radiation. Furthermore, phenylephrine induced a marked increase of NAMPT promoter activity. Conclusions: These findings reveal the regulatory mechanisms of NAMPT expression

  18. Nicotinamide Phosphoribosyltransferase Upregulation by Phenylephrine Reduces Radiation Injury in Submandibular Gland

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Bin, E-mail: xiangbin72@163.com [Laboratory of Oral and Maxillofacial Disease, Second Hospital of Dalian Medical University, Dalian (China); Han, Lichi [Department of Oral Medicine and Medical Research Center of Medical College, Dalian University, Dalian (China); Wang, Xinyue [Laboratory of Oral and Maxillofacial Disease, Second Hospital of Dalian Medical University, Dalian (China); Tang, Ling [Life Sciences and Technology College, Dalian University, Dalian (China); Li, Kailiang [Department of Oral and Maxillofacial Surgery, Second Hospital of Dalian Medical University, Dalian (China); Li, Xiuxiu [Department of Oral Medicine and Medical Research Center of Medical College, Dalian University, Dalian (China); Zhao, Xibo [Department of Oral and Maxillofacial Surgery, Second Hospital of Dalian Medical University, Dalian (China); Xia, Miaomiao [Department of Oral Medicine and Medical Research Center of Medical College, Dalian University, Dalian (China); Zhou, Xixi [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico (United States); Zhang, Fuyin [Department of Oral and Maxillofacial Surgery, Second Hospital of Dalian Medical University, Dalian (China); Liu, Ke Jian, E-mail: kliu@salud.unm.edu [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico (United States)

    2016-11-01

    Purpose: Radiation therapy for head and neck cancer commonly leads to radiation sialadenitis. Emerging evidence has indicated that phenylephrine pretreatment reduces radiosensitivity in the salivary gland; however, the underlying cytoprotective mechanism remains unclear. Nicotinamide phosphoribosyltransferase (NAMPT) is not only a key enzyme for the nicotinamide adenine dinucleotide salvage pathway, but also a cytokine participating in cell survival, metabolism, and longevity, with a broad effect on cellular functions in physiology and pathology. However, the regulatory events of NAMPT in response to the irradiated salivary gland are unknown. Methods and Materials: The cell viability of primary cultured submandibular gland cells was determined using the PrestoBlue assay. NAMPT expression was measured using reverse transcriptase polymerase chain reaction and Western blotting in vitro and in vivo. Silent information regulator 1 (SIRT1) and phosphorylated Akt protein levels were examined by Western blotting. The cellular locations of NAMPT and SIRT1 were detected by immunohistochemistry. NAMPT promoter activity was assessed using the luciferase reporter gene assay. Results: NAMPT was mainly distributed in the cytoplasm of granular convoluted tubule cells and ductal cells in normal submandibular glands. mRNA and protein expression of NAMPT was downregulated after radiation but upregulated with phenylephrine pretreatment both in vivo and in vitro. Moreover, the protein expression of phosphorylated Akt and SIRT1 was decreased in irradiated glands, and phenylephrine pretreatment restored the expression of both. SIRT1 was mainly located in the cell nucleus and cytoplasm in the normal submandibular gland. Phenylephrine dramatically enhanced the expression of SIRT1, which was significantly reduced by radiation. Furthermore, phenylephrine induced a marked increase of NAMPT promoter activity. Conclusions: These findings reveal the regulatory mechanisms of NAMPT expression

  19. A new approach to reduce uncertainties in space radiation cancer risk predictions.

    Directory of Open Access Journals (Sweden)

    Francis A Cucinotta

    Full Text Available The prediction of space radiation induced cancer risk carries large uncertainties with two of the largest uncertainties being radiation quality and dose-rate effects. In risk models the ratio of the quality factor (QF to the dose and dose-rate reduction effectiveness factor (DDREF parameter is used to scale organ doses for cosmic ray proton and high charge and energy (HZE particles to a hazard rate for γ-rays derived from human epidemiology data. In previous work, particle track structure concepts were used to formulate a space radiation QF function that is dependent on particle charge number Z, and kinetic energy per atomic mass unit, E. QF uncertainties where represented by subjective probability distribution functions (PDF for the three QF parameters that described its maximum value and shape parameters for Z and E dependences. Here I report on an analysis of a maximum QF parameter and its uncertainty using mouse tumor induction data. Because experimental data for risks at low doses of γ-rays are highly uncertain which impacts estimates of maximum values of relative biological effectiveness (RBEmax, I developed an alternate QF model, denoted QFγAcute where QFs are defined relative to higher acute γ-ray doses (0.5 to 3 Gy. The alternate model reduces the dependence of risk projections on the DDREF, however a DDREF is still needed for risk estimates for high-energy protons and other primary or secondary sparsely ionizing space radiation components. Risk projections (upper confidence levels (CL for space missions show a reduction of about 40% (CL∼50% using the QFγAcute model compared the QFs based on RBEmax and about 25% (CL∼35% compared to previous estimates. In addition, I discuss how a possible qualitative difference leading to increased tumor lethality for HZE particles compared to low LET radiation and background tumors remains a large uncertainty in risk estimates.

  20. Reducing Radiation Dose in Coronary Angiography and Angioplasty Using Image Noise Reduction Technology.

    Science.gov (United States)

    Kastrati, Mirlind; Langenbrink, Lukas; Piatkowski, Michal; Michaelsen, Jochen; Reimann, Doris; Hoffmann, Rainer

    2016-08-01

    This study sought to quantitatively evaluate the reduction of radiation dose in coronary angiography and angioplasty with the use of image noise reduction technology in a routine clinical setting. Radiation dose data from consecutive 605 coronary procedures (397 consecutive coronary angiograms and 208 consecutive coronary interventions) performed from October 2014 to April 2015 on a coronary angiography system with noise reduction technology (Allura Clarity IQ) were collected. For comparison, radiation dose data from consecutive 695 coronary procedures (435 coronary angiograms and 260 coronary interventions) performed on a conventional coronary angiography system from October 2013 to April 2014 were evaluated. Patient radiation dosage was evaluated based on the cumulative dose area product. Operators and operator practice did not change between the 2 evaluated periods. Patient characteristics were collected to evaluate similarity of patient groups. Image quality was evaluated on a 5-grade scale in 30 patients of each group. There were no significant differences between the 2 evaluated groups in gender, age, weight, and fluoroscopy time (6.8 ± 6.1 vs 6.9 ± 6.3 minutes, not significant). The dose area product was reduced from 3195 ± 2359 to 983 ± 972 cGycm(2) (65%, p technology. Image quality was graded as similar between the evaluated systems (4.0 ± 0.7 vs 4.2 ± 0.6, not significant). In conclusion, a new x-ray technology with image noise reduction algorithm provides a substantial reduction in radiation exposure without the need to prolong the procedure or fluoroscopy time. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Solar Ultraviolet-B Radiation Increases Phenolic Content and Ferric Reducing Antioxidant Power in Avena sativa

    Directory of Open Access Journals (Sweden)

    Christopher T. Ruhland

    2007-06-01

    Full Text Available We examined the influence of solar ultraviolet-B radiation (UV-B; 280-320 nm on the maximum photochemical efficiency of photosystem II (Fv/Fm, bulk-soluble phenolic concentrations, ferric-reducing antioxidant power (FRAP and growth of Avena sativa. Treatments involved placing filters on frames over potted plants that reduced levels of biologically effective UV-B by either 71% (reduced UV-B or by 19% (near-ambient UV-B over the 52 day experiment (04 July - 25 August 2002. Plants growing under near-ambient UV-B had 38% less total biomass than those under reduced UV-B. The reduction in biomass was mainly the result of a 24% lower leaf elongation rate, resulting in shorter leaves and less total leaf area than plants under reduced UV-B. In addition, plants growing under near-ambient UV-B had up to 17% lower Fv/Fm values early in the experiment, and this effect declined with plant age. Concentrations of bulk-soluble phenolics and FRAP values were 17 and 24% higher under near-ambient UV-B than under reduced UV-B, respectively. There was a positive relationship between bulk-soluble phenolic concentrations and FRAP values. There were no UV-B effects on concentrations of carotenoids (carotenes + xanthophylls.

  2. Reducing Anesthesia and Health Care Cost Through Utilization of Child Life Specialists in Pediatric Radiation Oncology

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Michael T. [Department of Radiation Oncology, University of Miami Sylvester Comprehensive Cancer Center and Jackson Memorial Hospital, Miami, Florida (United States); Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, Florida (United States); Todd, Kimberly E.; Oakley, Heather; Bradley, Julie A.; Rotondo, Ronny L.; Morris, Christopher G.; Klein, Stuart; Mendenhall, Nancy P. [Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, Florida (United States); Indelicato, Daniel J., E-mail: dindelicato@floridaproton.org [Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, Florida (United States)

    2016-10-01

    Purpose: To analyze the effectiveness of a certified child life specialist (CCLS) in reducing the frequency of daily anesthesia at our institution, and to quantify the potential health care payer cost savings of CCLS utilization in the United States. Methods and Materials: From 2006 to 2014, 738 children (aged ≤21 years) were treated with radiation therapy at our institution. We retrospectively analyzed the frequency of daily anesthesia before and after hiring a CCLS in 2011 after excluding patients aged 0 to 2 and >12 years. In the analyzed cohort of 425 patients the median age was 7.6 years (range, 3-12.9 years). For the pre-CCLS period the overall median age was 7.5 years; for the post-CCLS period the median age was 7.7 years. An average 6-week course of pediatric anesthesia for radiation therapy costs $50,000 in charges to the payer. The average annual cost to employ one CCLS is approximately $50,000. Results: Before employing a CCLS, 69 of 121 children (57%) aged 3 to 12 years required daily anesthesia, including 33 of 53 children (62.3%) aged 5 to 8 years. After employing a CCLS, 124 of 304 children (40.8%) aged 3 to 12 years required daily anesthesia, including only 34 of 118 children (28.8%) aged 5 to 8 years (P<.0001). With a >16% absolute reduction in anesthesia use after employment of a CCLS, the health care payer cost savings was approaching $50,000 per 6 children aged 3 to 12 years treated annually with radiation therapy in our institution. This reduction resulted in a total of only 6 children aged 3 to 12 years required anesthesia to be treated per year at our center to achieve nearly break-even cost savings to the health care payer if the payer were to subsidize the employment expense of a CCLS. Overall, the CCLS intervention can provide an average annualized health care payer cost savings of “$[(anesthesia cost to payer during radiation therapy course/6) − (CCLS expense to payer/N)]” per child (N) treated with radiation

  3. Reducing Anesthesia and Health Care Cost Through Utilization of Child Life Specialists in Pediatric Radiation Oncology.

    Science.gov (United States)

    Scott, Michael T; Todd, Kimberly E; Oakley, Heather; Bradley, Julie A; Rotondo, Ronny L; Morris, Christopher G; Klein, Stuart; Mendenhall, Nancy P; Indelicato, Daniel J

    2016-10-01

    To analyze the effectiveness of a certified child life specialist (CCLS) in reducing the frequency of daily anesthesia at our institution, and to quantify the potential health care payer cost savings of CCLS utilization in the United States. From 2006 to 2014, 738 children (aged ≤21 years) were treated with radiation therapy at our institution. We retrospectively analyzed the frequency of daily anesthesia before and after hiring a CCLS in 2011 after excluding patients aged 0 to 2 and >12 years. In the analyzed cohort of 425 patients the median age was 7.6 years (range, 3-12.9 years). For the pre-CCLS period the overall median age was 7.5 years; for the post-CCLS period the median age was 7.7 years. An average 6-week course of pediatric anesthesia for radiation therapy costs $50,000 in charges to the payer. The average annual cost to employ one CCLS is approximately $50,000. Before employing a CCLS, 69 of 121 children (57%) aged 3 to 12 years required daily anesthesia, including 33 of 53 children (62.3%) aged 5 to 8 years. After employing a CCLS, 124 of 304 children (40.8%) aged 3 to 12 years required daily anesthesia, including only 34 of 118 children (28.8%) aged 5 to 8 years (P16% absolute reduction in anesthesia use after employment of a CCLS, the health care payer cost savings was approaching $50,000 per 6 children aged 3 to 12 years treated annually with radiation therapy in our institution. This reduction resulted in a total of only 6 children aged 3 to 12 years required anesthesia to be treated per year at our center to achieve nearly break-even cost savings to the health care payer if the payer were to subsidize the employment expense of a CCLS. Overall, the CCLS intervention can provide an average annualized health care payer cost savings of "$[(anesthesia cost to payer during radiation therapy course/6) - (CCLS expense to payer/N)]" per child (N) treated with radiation therapy, where N equals the number of children aged 3 to 12

  4. Reducing Anesthesia and Health Care Cost Through Utilization of Child Life Specialists in Pediatric Radiation Oncology

    International Nuclear Information System (INIS)

    Scott, Michael T.; Todd, Kimberly E.; Oakley, Heather; Bradley, Julie A.; Rotondo, Ronny L.; Morris, Christopher G.; Klein, Stuart; Mendenhall, Nancy P.; Indelicato, Daniel J.

    2016-01-01

    Purpose: To analyze the effectiveness of a certified child life specialist (CCLS) in reducing the frequency of daily anesthesia at our institution, and to quantify the potential health care payer cost savings of CCLS utilization in the United States. Methods and Materials: From 2006 to 2014, 738 children (aged ≤21 years) were treated with radiation therapy at our institution. We retrospectively analyzed the frequency of daily anesthesia before and after hiring a CCLS in 2011 after excluding patients aged 0 to 2 and >12 years. In the analyzed cohort of 425 patients the median age was 7.6 years (range, 3-12.9 years). For the pre-CCLS period the overall median age was 7.5 years; for the post-CCLS period the median age was 7.7 years. An average 6-week course of pediatric anesthesia for radiation therapy costs $50,000 in charges to the payer. The average annual cost to employ one CCLS is approximately $50,000. Results: Before employing a CCLS, 69 of 121 children (57%) aged 3 to 12 years required daily anesthesia, including 33 of 53 children (62.3%) aged 5 to 8 years. After employing a CCLS, 124 of 304 children (40.8%) aged 3 to 12 years required daily anesthesia, including only 34 of 118 children (28.8%) aged 5 to 8 years (P 16% absolute reduction in anesthesia use after employment of a CCLS, the health care payer cost savings was approaching $50,000 per 6 children aged 3 to 12 years treated annually with radiation therapy in our institution. This reduction resulted in a total of only 6 children aged 3 to 12 years required anesthesia to be treated per year at our center to achieve nearly break-even cost savings to the health care payer if the payer were to subsidize the employment expense of a CCLS. Overall, the CCLS intervention can provide an average annualized health care payer cost savings of “$[(anesthesia cost to payer during radiation therapy course/6) − (CCLS expense to payer/N)]” per child (N) treated with radiation therapy, where N

  5. [Effects of reduced solar radiation on winter wheat flag leaf net photosynthetic rate].

    Science.gov (United States)

    Zheng, You-Fei; Ni, Yan-Li; Mai, Bo-Ru; Wu, Rong-Jun; Feng, Yan; Sun, Jian; Li, Jian; Xu, Jing-Xin

    2011-06-01

    Taking winter wheat Triticum aestivum L. (cv. Yangmai 13) as test material, a field experiment was conducted in Nanjing City to study the effects of simulated reduced solar radiation on the diurnal variation of winter wheat flag leaf photosynthetic rate and the main affecting factors. Five treatments were installed, i. e., 15% (T15), 20% (T20) , 40% (T40), 60% (T60), and 100% (CK) of total incident solar radiation. Reduced solar irradiance increased the chlorophyll and lutein contents significantly, but decreased the net photosynthetic rate (Pn). Under different solar irradiance, the diurnal variation of Pn had greater difference, and the daily maximum Pn was in the order of CK > T60 > T40 > T 20 > T15. In CK, the Pn exhibited a double peak diurnal curve; while in the other four treatments, the Pn showed a single peak curve, and the peak was lagged behind that of CK. Correlation analysis showed that reduced solar irradiance was the main factor affecting the diurnal variation of Pn, but the physiological parameters also played important roles in determining the diurnal variation of Pn. In treatments T60 and T40, the photosynthesis active radiation (PAR), leaf temperature (T1) , stomatal conductance (Gs) , and transpiration rate (Tr) were significantly positively correlated with Pn, suggesting their positive effects on Pn. The intercellular CO2 concentration (Ci) and stomatal limitation (Ls) had significant negative correlations with Pn in treatments T60 and T40 but significant positive correlations with Pn in treatments T20 and T15, implying that the Ci and Ls had negative (or positive) effects on Pn when the solar irradiance was higher (or lower) than 40% of incident solar irradiance.

  6. Reducing radiation doses to the breast, thyroid and gonads during diagnostic radiography

    International Nuclear Information System (INIS)

    Weatherburn, G.C.

    1983-01-01

    The measurement of doses to the gonads during radiography of the pelvis is discussed. Phantom measurements to estimate doses to the ovaries in antero-posterior (AP) and postero-anterior (PA) projections of the pelvis showed that the dose is 15% of the skin entry dose in the AP projection and 9% in the PA projection. The air gap technique and its applications in reducing radiation doses to the gonads, breast and thyroid is described. A summary of dose reduction factors for these radiosensitive organs achieved by modified radiographic techniques in radiography of the chest, pelvis, spine and skull is given. (U.K.)

  7. French experience to reduce radiation field build-up and improve nuclear fuel performance

    International Nuclear Information System (INIS)

    Thomazet, J.; Beslu, P.; Noe, M.; Stora, J.P.

    1983-01-01

    Over these last years, considerable information has been obtained on primary coolant chemistry, activity build-up and nuclear fuel behavior. As of December 1982, twenty three 900 MWe type reactors were in operation in France and about 1.3 millions of rods had been loaded in power reactors among which six regions of 17x17 fuel assemblies had completed successfully their third cycle of irradiation with a lead assembly burn-up of 37,000 MWd/MtU. Visual examination shows that crud deposited on fuel clads is mostly thin or inexistent. This result is due to the appropriate B/Li coolant concentration control which is currently applied in French reactors since several years. Correlatively, radiation field build-up is minimized and excessive external corrosion has never been observed. Nevertheless for higher coolant temperature plants, where occurrence of nucleate boiling could increase crud deposition, and for load follow and high burn-up operation, an extensive programme is performed jointly by Commissariat a l'Energie Atomique (CEA), Electricite de France, FRAMATOME and FRAGEMA to reduce even more the radiation field. This programme, described in the paper, includes: loop tests; on site chemical and radiochemical surveys; radiation field measurements; on site fuel examination crud-scrapping, crud analysis and oxide thickness measurements; hot cells examination. Some key results are presented and discussed in this paper. (author)

  8. The indirect effect of radiation reduces the repair fidelity of NHEJ as verified in repair deficient CHO cell lines exposed to different radiation qualities and potassium bromate

    International Nuclear Information System (INIS)

    Bajinskis, Ainars; Olsson, Gunilla; Harms-Ringdahl, Mats

    2012-01-01

    The complexity of DNA lesions induced by ionizing radiation is mainly dependent on radiation quality, where the indirect action of radiation may contribute to different extent depending on the type of radiation under study. The effect of indirect action of radiation can be investigated by using agents that induce oxidative DNA damage or by applying free radical scavengers. The aim of this study was to investigate the role of the indirect effect of radiation for the repair fidelity of non-homologous end-joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER) when DNA damage of different complexity was induced by gamma radiation, alpha particles or from base damages (8-oxo-dG) induced by potassium bromate (KBrO 3 ). CHO cells lines deficient in XRCC3 (HRR) irs1SF, XRCC7 (NHEJ) V3-3 and XRCC1 (BER) EM9 were irradiated in the absence or presence of the free radical scavenger dimethyl sulfoxide (DMSO). The endpoints investigated included rate of cell proliferation by the DRAG assay, clonogenic cell survival and the level of primary DNA damage by the comet assay. The results revealed that the indirect effect of low-LET radiation significantly reduced the repair fidelity of both NHEJ and HRR pathways. For high-LET radiation the indirect effect of radiation also significantly reduced the repair fidelity for the repair deficient cell lines. The results suggest further that the repair fidelity of the error prone NHEJ repair pathway is more impaired by the indirect effect of high-LET radiation relative to the other repair pathways studied. The response to bromate observed for the two DSB repair deficient cell lines strongly support earlier studies that bromate induces complex DNA damages. The significantly reduced repair fidelity of irs1SF and V3-3 suggests that NHEJ as well as HRR are needed for the repair, and that complex DSBs are formed after bromate exposure.

  9. The indirect effect of radiation reduces the repair fidelity of NHEJ as verified in repair deficient CHO cell lines exposed to different radiation qualities and potassium bromate

    Energy Technology Data Exchange (ETDEWEB)

    Bajinskis, Ainars, E-mail: ainars.bajinskis@gmt.su.se [Centre for Radiation Protection Research, Department of Genetics, Microbiology and Toxicology, Stockholm University, S-10691 Stockholm (Sweden); Olsson, Gunilla; Harms-Ringdahl, Mats [Centre for Radiation Protection Research, Department of Genetics, Microbiology and Toxicology, Stockholm University, S-10691 Stockholm (Sweden)

    2012-03-01

    The complexity of DNA lesions induced by ionizing radiation is mainly dependent on radiation quality, where the indirect action of radiation may contribute to different extent depending on the type of radiation under study. The effect of indirect action of radiation can be investigated by using agents that induce oxidative DNA damage or by applying free radical scavengers. The aim of this study was to investigate the role of the indirect effect of radiation for the repair fidelity of non-homologous end-joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER) when DNA damage of different complexity was induced by gamma radiation, alpha particles or from base damages (8-oxo-dG) induced by potassium bromate (KBrO{sub 3}). CHO cells lines deficient in XRCC3 (HRR) irs1SF, XRCC7 (NHEJ) V3-3 and XRCC1 (BER) EM9 were irradiated in the absence or presence of the free radical scavenger dimethyl sulfoxide (DMSO). The endpoints investigated included rate of cell proliferation by the DRAG assay, clonogenic cell survival and the level of primary DNA damage by the comet assay. The results revealed that the indirect effect of low-LET radiation significantly reduced the repair fidelity of both NHEJ and HRR pathways. For high-LET radiation the indirect effect of radiation also significantly reduced the repair fidelity for the repair deficient cell lines. The results suggest further that the repair fidelity of the error prone NHEJ repair pathway is more impaired by the indirect effect of high-LET radiation relative to the other repair pathways studied. The response to bromate observed for the two DSB repair deficient cell lines strongly support earlier studies that bromate induces complex DNA damages. The significantly reduced repair fidelity of irs1SF and V3-3 suggests that NHEJ as well as HRR are needed for the repair, and that complex DSBs are formed after bromate exposure.

  10. History of measures taken to reduce radiation exposure at Hamaoka Nuclear Power Station

    International Nuclear Information System (INIS)

    Kondou, Masashi; Takagi, Nobuyuki; Yabushita, Kazuo; Dekijima, Makoto

    2009-01-01

    Hamaoka Nuclear Power Station currently has five reactors, Units 1 to 5. Units 1 and 2 halted commercial operation in January 2009 and are now being prepared for decommissioning. Units 3 to 5 are operating at the rated thermal output with the gross electrical output of 3504 MWe. Hamaoka Nuclear Power Station has been operating for about 30 years since Unit 1 started up in 1976. Various measures have been taken to control water chemistry: for controlling SCC in the core internals and structural materials, hydrogen injection and noble metal injection were implemented; and to reduce radiation exposure for workers, condensate filter demineralizers were added, hollow fiber filters and pleated filters were installed in the condensate cleanup system, and zinc injection was performed. This paper describes measures taken at Hamaoka to reduce exposure in terms of water chemistry and techniques to monitor ion impurities in the reactor water. (author)

  11. Disease Control After Reduced Volume Conformal and Intensity Modulated Radiation Therapy for Childhood Craniopharyngioma

    Energy Technology Data Exchange (ETDEWEB)

    Merchant, Thomas E., E-mail: thomas.merchant@stjude.org [St Jude Children' s Research Hospital, Radiological Sciences, Memphis, Tennessee (United States); Kun, Larry E.; Hua, Chia-Ho [St Jude Children' s Research Hospital, Radiological Sciences, Memphis, Tennessee (United States); Wu, Shengjie; Xiong, Xiaoping [St Jude Children' s Research Hospital, Biostatistics, Memphis, Tennessee (United States); Sanford, Robert A.; Boop, Frederick A. [Semmes Murphey Neurologic and Spine Institute, Neurosurgery, Memphis, Tennessee (United States)

    2013-03-15

    Purpose: To estimate the rate of disease control after conformal radiation therapy using reduced clinical target volume (CTV) margins and to determine factors that predict for tumor progression. Methods and Materials: Eighty-eight children (median age, 8.5 years; range, 3.2-17.6 years) received conformal or intensity modulated radiation therapy between 1998 and 2009. The study group included those prospectively treated from 1998 to 2003, using a 10-mm CTV, defined as the margin surrounding the solid and cystic tumor targeted to receive the prescription dose of 54 Gy. The CTV margin was subsequently reduced after 2003, yielding 2 groups of patients: those treated with a CTV margin greater than 5 mm (n=26) and those treated with a CTV margin less than or equal to 5 mm (n=62). Disease progression was estimated on the basis of additional variables including sex, race, extent of resection, tumor interventions, target volume margins, and frequency of weekly surveillance magnetic resonance (MR) imaging during radiation therapy. Median follow-up was 5 years. Results: There was no difference between progression-free survival rates based on CTV margins (>5 mm vs ≤5 mm) at 5 years (88.1% ± 6.3% vs 96.2% ± 4.4% [P=.6386]). There were no differences based on planning target volume (PTV) margins (or combined CTV plus PTV margins). The PTV was systematically reduced from 5 to 3 mm during the time period of the study. Factors predictive of superior progression-free survival included Caucasian race (P=.0175), no requirement for cerebrospinal fluid shunting (P=.0066), and number of surveillance imaging studies during treatment (P=.0216). Patients whose treatment protocol included a higher number of weekly surveillance MR imaging evaluations had a lower rate of tumor progression. Conclusions: These results suggest that targeted volume reductions for radiation therapy using smaller margins are feasible and safe but require careful monitoring. We are currently investigating

  12. Electron beam radiation of dried fruits and nuts to reduce yeast and mold bioburden.

    Science.gov (United States)

    Ic, Erhan; Kottapalli, Bala; Maxim, Joseph; Pillai, Suresh D

    2007-04-01

    Dried fruits and nuts make up a significant portion of the commodities traded globally, and the presence of yeasts and molds on dried fruits and nuts can be a public health risk because of the potential for exposure to toxigenic fungi. Since current postharvest treatment technologies are rather limited for dried fruits and nuts, electron beam (E-beam) radiation experiments were performed to determine the doses required to reduce the yeast and mold bioburden of raisins, walnuts, and dates. The indigenous yeast and mold bioburden on a select number of commodities sold at retail ranged from 10(2) to 10(3) CFU/g. E-beam inactivation kinetics based on the linear model suggest that the decimal reduction dose required to eliminate 90% of the microbial population (D10-value) of these indigenous fungal populations ranges from 1.09 to 1.59 kGy. Some samples, however, exhibited inactivation kinetics that were better modeled by a quadratic model. The results indicate that different commodities can contain molds and yeasts of varying resistance to ionizing radiation. It is thus essential for the dried fruit and nut industry to determine empirically the minimum E-beam dose that is capable of reducing or eliminating the bioburden of yeasts and molds in their specific commodities.

  13. Reduced radiation exposure to the mammary glands in thoracic computed tomography using organ-based tube-current modulation

    International Nuclear Information System (INIS)

    Munechika, Jiro; Ohgiya, Yoshimitsu; Gokan, Takehiko; Hashimoto, Toshi; Iwai, Tsugunori

    2013-01-01

    Organ-based tube-current modulation has been used to reduce radiation exposure to specific organs. However, there are no reports yet published on reducing radiation exposure in clinical cases. In this study, we assessed the reduction in radiation exposure to the mammary glands during thoracic computed tomography (CT) using X-CARE. In a phantom experiment, the use of X-CARE reduced radiation exposure at the midline of the precordial region by a maximum of 45.1%. In our corresponding clinical study, CT was performed using X-CARE in 15 patients, and without X-CARE in another 15. Compared to the non-X-CARE group, radiation exposure was reduced in the X-CARE group at the midline of the precordial region by 22.3% (P 0.05). X-CARE thus reduced radiation exposure at the midline of the precordial region and allowed us to obtain consistent CT values without increasing noise. However, this study revealed increases in radiation exposure at the lateral sides of the breasts. It is conceivable that patients' breasts were laterally displaced by gravity under the standard thoracic imaging conditions. Further studies that consider factors such as body size and adjustment of imaging conditions may be needed in the future. (author)

  14. Reduced H3K27me3 expression in radiation-associated angiosarcoma of the breast

    DEFF Research Database (Denmark)

    Mentzel, Thomas; Kiss, Katalin

    2018-01-01

    The diagnosis of radiation-associated angiosarcoma is challenging and there are overlapping clinicopathological features between radiation-associated benign, atypical and malignant vascular lesions. It has been shown convincingly, that the majority of radiation-associated angiosarcomas are charac...

  15. Genome, transcriptome and methylome sequencing of a primitively eusocial wasp reveal a greatly reduced DNA methylation system in a social insect.

    Science.gov (United States)

    Standage, Daniel S; Berens, Ali J; Glastad, Karl M; Severin, Andrew J; Brendel, Volker P; Toth, Amy L

    2016-04-01

    Comparative genomics of social insects has been intensely pursued in recent years with the goal of providing insights into the evolution of social behaviour and its underlying genomic and epigenomic basis. However, the comparative approach has been hampered by a paucity of data on some of the most informative social forms (e.g. incipiently and primitively social) and taxa (especially members of the wasp family Vespidae) for studying social evolution. Here, we provide a draft genome of the primitively eusocial model insect Polistes dominula, accompanied by analysis of caste-related transcriptome and methylome sequence data for adult queens and workers. Polistes dominula possesses a fairly typical hymenopteran genome, but shows very low genomewide GC content and some evidence of reduced genome size. We found numerous caste-related differences in gene expression, with evidence that both conserved and novel genes are related to caste differences. Most strikingly, these -omics data reveal a major reduction in one of the major epigenetic mechanisms that has been previously suggested to be important for caste differences in social insects: DNA methylation. Along with a conspicuous loss of a key gene associated with environmentally responsive DNA methylation (the de novo DNA methyltransferase Dnmt3), these wasps have greatly reduced genomewide methylation to almost zero. In addition to providing a valuable resource for comparative analysis of social insect evolution, our integrative -omics data for this important behavioural and evolutionary model system call into question the general importance of DNA methylation in caste differences and evolution in social insects. © 2016 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  16. Reducing Radiation Dose in Adult Head CT using Iterative Reconstruction - A Clinical Study in 177 Patients.

    Science.gov (United States)

    Kaul, D; Kahn, J; Huizing, L; Wiener, E; Grupp, U; Böning, G; Ghadjar, P; Renz, D M; Streitparth, F

    2016-02-01

    To assess how ASIR (adaptive statistical iterative reconstruction) contributes to dose reduction and affects image quality of non-contrast cranial computed tomography (cCT). Non-contrast emergency CT scans of the head acquired in 177 patients were evaluated. The scans were acquired and processed using four different protocols: Group A (control): 120 kV, FBP (filtered back projection) n = 71; group B1: 120 kV, scan and reconstruction performed with 20 % ASIR (blending of 20 % ASIR and 80 % FBP), n = 86; group B2: raw data from group B1 reconstructed using a blending of 40 % ASIR and 60 % FBP, n = 74; group C1: 120 kV, scan and reconstruction performed with 30 % ASIR, n = 20; group C2: raw data from group C1 reconstructed using a blending of 50 % ASIR and 50 % FBP, n = 20. The effective dose was calculated. Image quality was assessed quantitatively and qualitatively. Compared to group A, groups B1/2 and C1/2 showed a significantly reduced effective dose of 40.4 % and 73.3 % (p ASIR makes it possible to reduce radiation significantly while maintaining adequate image quality in non-contrast head CT, which may be particularly useful for younger patients in an emergency setting and in follow-up. ASIR may reduce radiation significantly while maintaining adequate image quality. cCT protocol with 20 % ASIR and 40 %ASIR/60 %FBP blending is adequate for everyday clinical use. cCT protocol with 30 % ASIR and 50 %ASIR/50 %FBP blending is adequate for follow-up imaging © Georg Thieme Verlag KG Stuttgart · New York.

  17. Can Angiotensin-Converting Enzyme Inhibitors Reduce the Incidence, Severity, and Duration of Radiation Proctitis?

    International Nuclear Information System (INIS)

    Alashkham, Abduelmenem; Paterson, Catherine; Rauchhaus, Petra; Nabi, Ghulam

    2016-01-01

    significantly less likely to have high-grade proctitis after radical radiation therapy with neoadjuvant or adjuvant hormone therapy (P<.001). The intake of ACEIs was significantly associated with a reduced risk of radiation-induced proctitis and also with acceleration of its resolution.

  18. Can Angiotensin-Converting Enzyme Inhibitors Reduce the Incidence, Severity, and Duration of Radiation Proctitis?

    Energy Technology Data Exchange (ETDEWEB)

    Alashkham, Abduelmenem, E-mail: alashkham@yahoo.com [Academic Section of Urology, Division of Cancer Research, School of Medicine, University of Dundee, Scotland (United Kingdom); Paterson, Catherine [Academic Section of Urology, Division of Cancer Research, School of Medicine, University of Dundee, Scotland (United Kingdom); Rauchhaus, Petra [Tayside Clinical Trials Unit, School of Medicine, University of Dundee, Scotland (United Kingdom); Nabi, Ghulam [Academic Section of Urology, Division of Cancer Research, School of Medicine, University of Dundee, Scotland (United Kingdom)

    2016-01-01

    significantly less likely to have high-grade proctitis after radical radiation therapy with neoadjuvant or adjuvant hormone therapy (P<.001). The intake of ACEIs was significantly associated with a reduced risk of radiation-induced proctitis and also with acceleration of its resolution.

  19. Great Apes

    Science.gov (United States)

    Sleeman, Jonathan M.; Cerveny, Shannon

    2014-01-01

    Anesthesia of great apes is often necessary to conduct diagnostic analysis, provide therapeutics, facilitate surgical procedures, and enable transport and translocation for conservation purposes. Due to the stress of remote delivery injection of anesthetic agents, recent studies have focused on oral delivery and/or transmucosal absorption of preanesthetic and anesthetic agents. Maintenance of the airway and provision of oxygen is an important aspect of anesthesia in great ape species. The provision of analgesia is an important aspect of the anesthesia protocol for any procedure involving painful stimuli. Opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) are often administered alone, or in combination to provide multi-modal analgesia. There is increasing conservation management of in situ great ape populations, which has resulted in the development of field anesthesia techniques for free-living great apes for the purposes of translocation, reintroduction into the wild, and clinical interventions.

  20. Low-dose biplanar radiography can be used in children and adolescents to accurately assess femoral and tibial torsion and greatly reduce irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Meyrignac, Olivier; Baunin, Christiane; Vial, Julie; Sans, Nicolas [CHU Toulouse Purpan, Department of Radiology, Toulouse Cedex 9 (France); Moreno, Ramiro [ALARA Expertise, Oberhausbergen (France); Accadbled, Franck; Gauzy, Jerome Sales de [Hopital des Enfants, Department of Orthopedics, Toulouse Cedex 9 (France); Sommet, Agnes [Universite Paul Sabatier, Department of Fundamental Pharmaco-Clinical Pharmacology, Toulouse (France)

    2015-06-01

    To evaluate in children the agreement between femoral and tibial torsion measurements obtained with low-dose biplanar radiography (LDBR) and CT, and to study dose reduction ratio between these two techniques both in vitro and in vivo. Thirty children with lower limb torsion abnormalities were included in a prospective study. Biplanar radiographs and CTs were performed for measurements of lower limb torsion on each patient. Values were compared using Bland-Altman plots. Interreader and intrareader agreements were evaluated by intraclass correlation coefficients. Comparative dosimetric study was performed using an ionization chamber in a tissue-equivalent phantom, and with thermoluminescent dosimeters in 5 patients. Average differences between CT and LDBR measurements were -0.1 ±1.1 for femoral torsion and -0.7 ±1.4 for tibial torsion. Interreader agreement for LDBR measurements was very good for both femoral torsion (FT) (0.81) and tibial torsion (TT) (0.87). Intrareader agreement was excellent for FT (0.97) and TT (0.89). The ratio between CT scan dose and LDBR dose was 22 in vitro (absorbed dose) and 32 in vivo (skin dose). Lower limb torsion measurements obtained with LDBR are comparable to CT measurements in children and adolescents, with a considerably reduced radiation dose. (orig.)

  1. Reduced recurrence of late hemorrhagic radiation cystitis by WF10 therapy in cervical cancer patients

    International Nuclear Information System (INIS)

    Veerasarn, Vutisiri; Khorprasert, Chonlakiet; Lorvidhaya, Vicharn; Sangruchi, Supatra; Tantivatana, Thanatip; Narkwong, Ladawan; Kongthanarat, Yongyut; Chitapanarux, Imjai; Tesavibul, Chanawat; Panichevaluk, Apichart; Puribhat, Sirisak; Sangkittipaiboon, Somphob; Sookpreedee, Lak; Lertsanguansinchai, Prasert; Phromratanapongse, Pramook; Rungpoka, Poonkiat; Trithratipvikul, Supamitr; Lojanapiwat, Bannakij; Ruangdilokrat, Sathit; Ngampanprasert, Pichai

    2004-01-01

    Background and purpose: To evaluate the efficacy and the safety of WF10 as adjunct to standard treatment in the management of late hemorrhagic radiation cystitis compared to standard treatment alone. Patients and methods: Cervical cancer patients with Grade 2 or 3 late hemorrhagic radiation cystitis, were randomized and treated with WF10 0.5 ml/kg body weight, diluted in physiological saline or 5% dextrose water 250 ml, intravenous infusions over 2 h on 5 consecutive days, every 3 weeks for 2 cycles plus standard treatment (WF10 group) or standard treatment alone (control group). Fifty patients in each group were evaluated by questioning; urinalysis and cystoscopy during a 1 year follow up. Results: At week 7, 37 patients (74%) in the WF10 group and 32 patients (64%) in the control group showed complete resolution in objective hematuria (P=0.28). Significantly lower use of antibiotics (P=0.002) and antispasmodics (P<0.001) was found in the WF10 group. Among the responders, 24 patients (77%) in the control group experienced recurrent objective hematuria, whereas in the WF10 group only 17 patients (47%) experienced a recurrence (P=0.01). Recurrence of objective hematuria occurred significantly faster in the control group as evidenced by Kaplan-Meier and log-rank statistics (P=0.004), suggesting a long-term effect of WF10. Cystoscopy, at the end of the treatment period and after the one year follow up showed overall improvement without significant difference between two groups. No severe toxicity was monitored. Conclusions: WF10 therapy is a safe, non-invasive and convenient method in the management of late hemorrhagic radiation cystitis. WF10 therapy, as adjunct to standard treatment, has significantly reduced recurrence of objective hematuria, compared to standard treatment alone, during a one year follow up

  2. Diagnostic accuracy at several reduced radiation dose levels for CT imaging in the diagnosis of appendicitis

    Science.gov (United States)

    Zhang, Di; Khatonabadi, Maryam; Kim, Hyun; Jude, Matilda; Zaragoza, Edward; Lee, Margaret; Patel, Maitraya; Poon, Cheryce; Douek, Michael; Andrews-Tang, Denise; Doepke, Laura; McNitt-Gray, Shawn; Cagnon, Chris; DeMarco, John; McNitt-Gray, Michael

    2012-03-01

    Purpose: While several studies have investigated the tradeoffs between radiation dose and image quality (noise) in CT imaging, the purpose of this study was to take this analysis a step further by investigating the tradeoffs between patient radiation dose (including organ dose) and diagnostic accuracy in diagnosis of appendicitis using CT. Methods: This study was IRB approved and utilized data from 20 patients who underwent clinical CT exams for indications of appendicitis. Medical record review established true diagnosis of appendicitis, with 10 positives and 10 negatives. A validated software tool used raw projection data from each scan to create simulated images at lower dose levels (70%, 50%, 30%, 20% of original). An observer study was performed with 6 radiologists reviewing each case at each dose level in random order over several sessions. Readers assessed image quality and provided confidence in their diagnosis of appendicitis, each on a 5 point scale. Liver doses at each case and each dose level were estimated using Monte Carlo simulation based methods. Results: Overall diagnostic accuracy varies across dose levels: 92%, 93%, 91%, 90% and 90% across the 100%, 70%, 50%, 30% and 20% dose levels respectively. And it is 93%, 95%, 88%, 90% and 90% across the 13.5-22mGy, 9.6-13.5mGy, 6.4-9.6mGy, 4-6.4mGy, and 2-4mGy liver dose ranges respectively. Only 4 out of 600 observations were rated "unacceptable" for image quality. Conclusion: The results from this pilot study indicate that the diagnostic accuracy does not change dramatically even at significantly reduced radiation dose.

  3. Bolus effect to reduce skin dose of the caontralateral breast during breast cancer radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Won, Young Jin [Dept. of Radiation Oncology, InJe University Ilsan Paik Hospital, Goyang (Korea, Republic of); Kim, Jong Won; Kim, Jung Hoon [Dept. of Radiology, Radiation Oncology, KonYang University Hospital, Daejeon (Korea, Republic of)

    2017-06-15

    The aim of this study was to evaluate the dose comparison using Radon phantom with 5 mm and 10 mm tissue equivalent materials, FIF, Wedge(15, 30 angle) and IMRT, to reduce the skin dose of the contralateral breast during breast cancer radiation therapy(Total dose: 50.4Gy). The dose was measured for each treatment plan by attaching to the 8 point of the contralateral breast of the treated region using a optical-stimulated luminance dosimeter(OSLD) as a comparative dose evaluation method. Of the OSLD used in the study, 10 were used with reproducibility within 3%. As a result, the average reduction rates of 5 mm and 10 mm in the FIF treatment plan were 37.23 cGy and 41.77 cGy, respectively, and the average reduction rates in the treatment plan using Wedge 15 degrees were 70.69 cGy and 87.57 cGy, respectively. The IMRT showed a reduction of 67.37 cGy and 83.17 cGy, respectively. The results of using bolus showed that as the thickness of the bolus increased in all treatments, the dose reduction increased. We concluded that mastectomy as well as general radiotherapy for breast cancer would be very effective for patients who are more likely to be exposed to scattered radiation due to a more demanding or complex treatment plan.

  4. REDUCING THE IMPACT OF RADIATION FACTORS IN AREAS WITH HIGH LEVEL OF RISK

    Directory of Open Access Journals (Sweden)

    D. A. Zaredinov

    2015-01-01

    Full Text Available The article is devoted to the modern problems of radioecology. The study reveals the problems of radioecological situation in some regions of the Republic of Uzbekistan. The main attention of the authors is paid to the ecologically hazardous objects in the uranium mining industry. The characteristics of wastes from uranium mining and stages of development of the mining industry are described. The historical background of the accumulation of the wastes in dumps, the ore-bearing rocks, and other off-balance ores is given. The practical experience and directions radio-ecological safety are generalized, achieving improvements of the environmental quality in areas with high risk. In conclusion, the authors recommend carrying out some measures to reduce an impact of the radiation factor on human health and to stabilize the radioecological situation at the studied regions.

  5. Optimising motivation and reducing burnout for radiation oncology trainees: A framework using self-determination theory.

    Science.gov (United States)

    Poulsen, Michael; Poulsen, Anne A

    2018-05-02

    Radiation oncology trainees in Australia and New Zealand have relatively high levels of emotional exhaustion and depersonalisation which are core components of burnout. The stresses of a demanding clinical load, studying for exams as well as family commitments are all contributing factors. Self-Deter mination Theory (SDT) provides a framework for optimising motivation which may be intrinsic or extrinsic. The three core components of SDT are competence, relatedness and autonomy. These factors should be addressed at a college level, Institutional and a personal level if the best outcomes are to be achieved. An environment that supports the individual's experience of competency, relatedness and autonomy will foster motivation and work engagement which in turn will improve performance, energy, resilience and creativity and reduce levels of burnout. © 2018 The Royal Australian and New Zealand College of Radiologists.

  6. Decontamination reduces radiation anxiety and improves subjective well-being after the Fukushima accident

    International Nuclear Information System (INIS)

    Murakami, Michio; Harada, Shigeki; Oki, Taikan

    2017-01-01

    Since the 2011 Fukushima accident, rebuilding society to protect against anxiety and improve feelings of well-being has grown in importance. A questionnaire was carried out among residents of Marumori Town, Igu County, Miyagi Prefecture, to evaluate the effects of radiation-related countermeasures implemented by the town to reduce residents' anxiety and improve their subjective well-being (response rate: 31%; valid responses: n = 174). Further, to propose effective countermeasures regarding town planning for the improvement in subjective well-being, we analyzed associations between residents' sense of attachment to the town and subjective well-being, and then identified primary factors behind their sense of attachment. Marumori Town, located about 50 km to the northwest of the Daiichi Nuclear Power Station, is a good site for evaluating the effects of countermeasures taken by the town itself to fight anxiety, because there have been limited surveys and professional medical support, and mitigation efforts were primarily initiated by the town. The results suggested that decontamination evaluations were associated with a reduction in anxiety after the accident, which contributed to an increase in residents' subjective well-being. On the other hand, the evaluation of items related to human interactions in the community and the natural environment was found as a primary factor of sense of attachment toward the town, which contributed to an increase of residents' subjective well-being. This is the first study to quantitatively measure the effects of radiation-related countermeasures on reducing anxiety and to propose an effective policy approach for improving subjective well-being. (author)

  7. Radiation therapy rather than prior surgery reduces extent of resection during endonasal endoscopic reoperation for craniopharyngioma.

    Science.gov (United States)

    Younus, Iyan; Forbes, Jonathan A; Ordóñez-Rubiano, Edgar G; Avendano-Pradel, Rafael; La Corte, Emanuele; Anand, Vijay K; Schwartz, Theodore H

    2018-07-01

    Radiation therapy is often advocated for residual or recurrent craniopharyngioma following surgical resection to prevent local recurrence. However, radiation therapy is not always effective and may render tumors more difficult to remove. If this is the case, patients may benefit more from reoperation if gross total resection can be achieved. Nevertheless, there is little data on the impact of radiation on reoperations for craniopharyngioma. In this study, we sought to analyze whether a history of previous radiation therapy (RT) affected extent of resection in patients with recurrent craniopharyngiomas subsequently treated with reoperation via endoscopic endonasal approach (EEA). The authors reviewed a prospectively acquired database of EEA reoperations of craniopharyngiomas over 13 years at Weill Cornell, NewYork-Presbyterian Hospital. All procedures were performed by the senior author. The operations were separated into two groups based on whether the patient had surgery alone (group A) or surgery and RT (group B) prior to recurrence. A total of 24 patients (16 male, 8 female) who underwent surgery for recurrent craniopharyngioma were identified. The average time to recurrence was 7.64 ± 4.34 months (range 3-16 months) for group A and 16.62 ± 12.1 months (range 6-45 months) for group B (p < 0.05). The average tumor size at recurrence was smaller in group A (1.85 ± 0.72 cm; range 0.5-3.2) than group B (2.59 ± 0.91 cm; range 1.5-4.6; p = 0.00017). Gross total resection (GTR) was achieved in 91% (10/11) of patients in group A and 54% (7/13) of patients in group B (p = 0.047). There was a near significant trend for higher average Karnofsky performance status (KPS) score at last follow-up for group A (83 ± 10.6) compared with group B (70 ± 16.3, p = 0.056). While RT for residual or recurrent craniopharyngioma may delay time to recurrence, ability to achieve GTR with additional surgery is reduced. In the case of

  8. Reduced recanalization rates of the great saphenous vein after endovenous laser treatment with increased energy dosing: definition of a threshold for the endovenous fluence equivalent.

    Science.gov (United States)

    Proebstle, Thomas Michael; Moehler, Thomas; Herdemann, Sylvia

    2006-10-01

    Recent reports indicated a correlation between the amount of energy released during endovenous laser treatment (ELT) of the great saphenous vein (GSV) and the success and durability of the procedure. Our objective was to analyze the influence of increased energy dosing on immediate occlusion and recanalization rates after ELT of the GSV. GSVs were treated with either 15 or 30 W of laser power by using a 940-nm diode laser with continuous fiber pullback and tumescent local anesthesia. Patients were followed up prospectively with duplex ultrasonography at day 1 and at 1, 3, 6, and 12 months. A total of 114 GSVs were treated with 15 W, and 149 GSVs were treated with 30 W. The average endovenous fluence equivalents were 12.8 +/- 5.1 J/cm2 and 35.1 +/- 15.6 J/cm2, respectively. GSV occlusion rates according to the method of Kaplan and Meier for the 15- and 30-W groups were 95.6% and 100%, respectively, at day 1, 90.4% and 100% at 3 months, and 82.7% and 97.0% at 12 months after ELT (log-rank; P = .001). An endovenous fluence equivalent exceeding 20 J/cm2 was associated with durable GSV occlusion after 12 months' follow-up, thus suggesting a schedule for dosing of laser energy with respect to the vein diameter. Higher dosing of laser energy shows a 100% immediate success rate and a significantly reduced recanalization rate during 12 months' follow-up.

  9. Direct aperture optimization as a means of reducing the complexity of intensity modulated radiation therapy plans

    International Nuclear Information System (INIS)

    Broderick, Maria; Leech, Michelle; Coffey, Mary

    2009-01-01

    Intensity Modulated Radiation Therapy (IMRT) is a means of delivering radiation therapy where the intensity of the beam is varied within the treatment field. This is done by dividing a large beam into many small beamlets. Dose constraints are assigned to both the target and sensitive structures and computerised inverse optimization is performed to find the individual weights of this large number of beamlets. The computer adjusts the intensities of these beamlets according to the required planning dose objectives. The optimized intensity patterns are then decomposed into a series of deliverable multi leaf collimator (MLC) shapes in the sequencing step. One of the main problems of IMRT, which becomes even more apparent as the complexity of the IMRT plan increases, is the dramatic increase in the number of Monitor Units (MU) required to deliver a fractionated treatment. The difficulty with this increase in MU is its association with increased treatment times and a greater leakage of radiation from the MLCs increasing the total body dose and the risk of secondary cancers in patients. Therefore one attempts to find ways of reducing these MU without compromising plan quality. The design of inverse planning systems where the beam is divided into small beamlets to produce the required intensity map automatically introduces complexity into IMRT treatment planning. Plan complexity is associated with many negative factors such as dosimetric uncertainty and delivery issues A large search space is required necessitating much computing power. However, the limitations of the delivery technology are not taken into consideration when designing the ideal intensity map therefore a further step termed the sequencing step is required to convert the ideal intensity map into a deliverable one. Many approaches have been taken to reduce the complexity. These include setting intensity limits, putting penalties on the cost function and using smoothing filters Direct Aperture optimization

  10. Direct aperture optimization as a means of reducing the complexity of intensity modulated radiation therapy plans

    Directory of Open Access Journals (Sweden)

    Coffey Mary

    2009-02-01

    Full Text Available Abstract Intensity Modulated Radiation Therapy (IMRT is a means of delivering radiation therapy where the intensity of the beam is varied within the treatment field. This is done by dividing a large beam into many small beamlets. Dose constraints are assigned to both the target and sensitive structures and computerised inverse optimization is performed to find the individual weights of this large number of beamlets. The computer adjusts the intensities of these beamlets according to the required planning dose objectives. The optimized intensity patterns are then decomposed into a series of deliverable multi leaf collimator (MLC shapes in the sequencing step. One of the main problems of IMRT, which becomes even more apparent as the complexity of the IMRT plan increases, is the dramatic increase in the number of Monitor Units (MU required to deliver a fractionated treatment. The difficulty with this increase in MU is its association with increased treatment times and a greater leakage of radiation from the MLCs increasing the total body dose and the risk of secondary cancers in patients. Therefore one attempts to find ways of reducing these MU without compromising plan quality. The design of inverse planning systems where the beam is divided into small beamlets to produce the required intensity map automatically introduces complexity into IMRT treatment planning. Plan complexity is associated with many negative factors such as dosimetric uncertainty and delivery issues A large search space is required necessitating much computing power. However, the limitations of the delivery technology are not taken into consideration when designing the ideal intensity map therefore a further step termed the sequencing step is required to convert the ideal intensity map into a deliverable one. Many approaches have been taken to reduce the complexity. These include setting intensity limits, putting penalties on the cost function and using smoothing filters Direct

  11. Direct aperture optimization as a means of reducing the complexity of intensity modulated radiation therapy plans

    Energy Technology Data Exchange (ETDEWEB)

    Broderick, Maria; Leech, Michelle; Coffey, Mary [Division of Radiation Therapy, School of Medicine, Trinity College Dublin, Dublin, Ireland (United Kingdom)

    2009-02-16

    Intensity Modulated Radiation Therapy (IMRT) is a means of delivering radiation therapy where the intensity of the beam is varied within the treatment field. This is done by dividing a large beam into many small beamlets. Dose constraints are assigned to both the target and sensitive structures and computerised inverse optimization is performed to find the individual weights of this large number of beamlets. The computer adjusts the intensities of these beamlets according to the required planning dose objectives. The optimized intensity patterns are then decomposed into a series of deliverable multi leaf collimator (MLC) shapes in the sequencing step. One of the main problems of IMRT, which becomes even more apparent as the complexity of the IMRT plan increases, is the dramatic increase in the number of Monitor Units (MU) required to deliver a fractionated treatment. The difficulty with this increase in MU is its association with increased treatment times and a greater leakage of radiation from the MLCs increasing the total body dose and the risk of secondary cancers in patients. Therefore one attempts to find ways of reducing these MU without compromising plan quality. The design of inverse planning systems where the beam is divided into small beamlets to produce the required intensity map automatically introduces complexity into IMRT treatment planning. Plan complexity is associated with many negative factors such as dosimetric uncertainty and delivery issues A large search space is required necessitating much computing power. However, the limitations of the delivery technology are not taken into consideration when designing the ideal intensity map therefore a further step termed the sequencing step is required to convert the ideal intensity map into a deliverable one. Many approaches have been taken to reduce the complexity. These include setting intensity limits, putting penalties on the cost function and using smoothing filters Direct Aperture optimization

  12. Effects of reduced natural background radiation on Drosophila melanogaster growth and development as revealed by the FLYINGLOW program.

    Science.gov (United States)

    Morciano, Patrizia; Iorio, Roberto; Iovino, Daniela; Cipressa, Francesca; Esposito, Giuseppe; Porrazzo, Antonella; Satta, Luigi; Alesse, Edoardo; Tabocchini, Maria Antonella; Cenci, Giovanni

    2018-01-01

    Natural background radiation of Earth and cosmic rays played a relevant role during the evolution of living organisms. However, how chronic low doses of radiation can affect biological processes is still unclear. Previous data have indicated that cells grown at the Gran Sasso Underground Laboratory (LNGS, L'Aquila) of National Institute of Nuclear Physics (INFN) of Italy, where the dose rate of cosmic rays and neutrons is significantly reduced with respect to the external environment, elicited an impaired response against endogenous damage as compared to cells grown outside LNGS. This suggests that environmental radiation contributes to the development of defense mechanisms at cellular level. To further understand how environmental radiation affects metabolism of living organisms, we have recently launched the FLYINGLOW program that aims at exploiting Drosophila melanogaster as a model for evaluating the effects of low doses/dose rates of radiation at the organismal level. Here, we will present a comparative data set on lifespan, motility and fertility from different Drosophila strains grown in parallel at LNGS and in a reference laboratory at the University of L'Aquila. Our data suggest the reduced radiation environment can influence Drosophila development and, depending on the genetic background, may affect viability for several generations even when flies are moved back to normal background radiation. As flies are considered a valuable model for human biology, our results might shed some light on understanding the effect of low dose radiation also in humans. © 2017 Wiley Periodicals, Inc.

  13. Breast Intensity-Modulated Radiation Therapy Reduces Time Spent With Acute Dermatitis for Women of All Breast Sizes During Radiation

    International Nuclear Information System (INIS)

    Freedman, Gary M.; Li Tianyu; Nicolaou, Nicos; Chen Yan; Ma, Charlie C.-M.; Anderson, Penny R.

    2009-01-01

    Purpose: To study the time spent with radiation-induced dermatitis during a course of radiation therapy for breast cancer in women treated with conventional or intensity-modulated radiation therapy (IMRT). Methods and Materials: The study population consisted of 804 consecutive women with early-stage breast cancer treated with breast-conserving surgery and radiation from 2001 to 2006. All patients were treated with whole-breast radiation followed by a boost to the tumor bed. Whole-breast radiation consisted of conventional wedged photon tangents (n = 405) earlier in the study period and mostly of photon IMRT (n = 399) in later years. All patients had acute dermatitis graded each week of treatment. Results: The breakdown of the cases of maximum acute dermatitis by grade was as follows: 3%, Grade 0; 34%, Grade 1; 61%, Grade 2; and 2%, Grade 3. The breakdown of cases of maximum toxicity by technique was as follows: 48%, Grade 0/1, and 52%, Grade 2/3, for IMRT; and 25%, Grade 0/1, and 75%, Grade 2/3, for conventional radiation therapy (p < 0.0001). The IMRT patients spent 82% of weeks during treatment with Grade 0/1 dermatitis and 18% with Grade 2/3 dermatitis, compared with 29% and 71% of patients, respectively, treated with conventional radiation (p < 0.0001). Furthermore, the time spent with Grade 2/3 toxicity was decreased in IMRT patients with small (p = 0.0015), medium (p < 0.0001), and large (p < 0.0001) breasts. Conclusions: Breast IMRT is associated with a significant decrease both in the time spent during treatment with Grade 2/3 dermatitis and in the maximum severity of dermatitis compared with that associated with conventional radiation, regardless of breast size.

  14. Great Expectations

    NARCIS (Netherlands)

    Dickens, Charles

    2005-01-01

    One of Dickens's most renowned and enjoyable novels, Great Expectations tells the story of Pip, an orphan boy who wishes to transcend his humble origins and finds himself unexpectedly given the opportunity to live a life of wealth and respectability. Over the course of the tale, in which Pip

  15. Reducing radiation doses to the breast, thyroid and gonads during diagnostic radiography

    International Nuclear Information System (INIS)

    Weatherburn, G.C.

    1983-01-01

    The skin entry and exit doses on patients undergoing routine radiographic examinations of areas in which the breast, thyroid and gonads are included in the primary beam were measured using thermoluminescent dosimeters. To obtain further information about patient doses, measurements were also made on a phantom at similar skin positions and at the positions of these organs. Comparisons of the doses to these radiosensitive organs were made for the antero-posterior and postero-anterior projections. In cases where it was found that the doses were reduced by the use of non-conventional relationship between the relative positions of the patient and the film, suggestions are made for the adaptations which would have to be made to X-ray equipment to enable these projections to be taken routinely. Other techniques, such as air gap techniques and thyroid shielding, whereby patient doses can be reduced during routine radiography are also examined. Finally the implications of these results for radiation protection of patients are considered. (author)

  16. Monitoring and forecasting of radiation hazard from great solar energetic particle events by using on-line one-min neutron monitor and satellite data

    International Nuclear Information System (INIS)

    Dorman, L. I.

    2007-01-01

    The method of automatically determining the start of great solar energetic particle (SEP) events are described on the basis of cosmic ray (CR) one-min observations by neutron monitors in real-time scale. It is shown that the probabilities of false alarms and missed triggers are negligible. After the start of SEP event, it is automatically determined by the method of coupling functions the SEP energy spectrum and flux for each minute of observations. By solving the inverse problem during few first minutes of SEP event, diffusion coefficient in the interplanetary space, source function on the Sun, and time of ejection of SEP into solar wind are determined. For extending obtained results into small energy range we use also available from Internet the satellite one-min CR data. This make possible to give forecast of space-time variation of SEP for more than 2 days and estimate expected radiation dose for satellite and aircraft. With each new minute of observations, the quality of forecast increased, and after ∼30 min became near 100%. (authors)

  17. The indirect effect of radiation reduces the repair fidelity of NHEJ as verified in repair deficient CHO cell lines exposed to different radiation qualities and potassium bromate.

    Science.gov (United States)

    Bajinskis, Ainars; Olsson, Gunilla; Harms-Ringdahl, Mats

    2012-03-01

    The complexity of DNA lesions induced by ionizing radiation is mainly dependent on radiation quality, where the indirect action of radiation may contribute to different extent depending on the type of radiation under study. The effect of indirect action of radiation can be investigated by using agents that induce oxidative DNA damage or by applying free radical scavengers. The aim of this study was to investigate the role of the indirect effect of radiation for the repair fidelity of non-homologous end-joining (NHEJ), homologous recombination repair (HRR) and base excision repair (BER) when DNA damage of different complexity was induced by gamma radiation, alpha particles or from base damages (8-oxo-dG) induced by potassium bromate (KBrO(3)). CHO cells lines deficient in XRCC3 (HRR) irs1SF, XRCC7 (NHEJ) V3-3 and XRCC1 (BER) EM9 were irradiated in the absence or presence of the free radical scavenger dimethyl sulfoxide (DMSO). The endpoints investigated included rate of cell proliferation by the DRAG assay, clonogenic cell survival and the level of primary DNA damage by the comet assay. The results revealed that the indirect effect of low-LET radiation significantly reduced the repair fidelity of both NHEJ and HRR pathways. For high-LET radiation the indirect effect of radiation also significantly reduced the repair fidelity for the repair deficient cell lines. The results suggest further that the repair fidelity of the error prone NHEJ repair pathway is more impaired by the indirect effect of high-LET radiation relative to the other repair pathways studied. The response to bromate observed for the two DSB repair deficient cell lines strongly support earlier studies that bromate induces complex DNA damages. The significantly reduced repair fidelity of irs1SF and V3-3 suggests that NHEJ as well as HRR are needed for the repair, and that complex DSBs are formed after bromate exposure. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Reducing radiation dose in adult head CT using iterative reconstruction. A clinical study in 177 patients

    Energy Technology Data Exchange (ETDEWEB)

    Kaul, D. [Charite School of Medicine and University Hospital, Berlin (Germany). Dept. of Radiology; Charite School of Medicine and University Hospital, Berlin (Germany). Dept. of Radiation Oncology; Kahn, J.; Huizing, L.; Wiener, E.; Grupp, U.; Boening, G.; Streitparth, F. [Charite School of Medicine and University Hospital, Berlin (Germany). Dept. of Radiology; Ghadjar, P. [Charite School of Medicine and University Hospital, Berlin (Germany). Dept. of Radiation Oncology; Renz, D.M. [Jena University Hospital (Germany). Dept. of Radiology

    2016-02-15

    To assess how ASIR (adaptive statistical iterative reconstruction) contributes to dose reduction and affects image quality of non-contrast cranial computed tomography (cCT). Non-contrast emergency CT scans of the head acquired in 177 patients were evaluated. The scans were acquired and processed using four different protocols: Group A (control): 120 kV, FBP (filtered back projection) n=71; group B1: 120 kV, scan and reconstruction performed with 20 % ASIR (blending of 20 % ASIR and 80 % FBP), n=86; group B2: raw data from group B1 reconstructed using a blending of 40 % ASIR and 60 % FBP, n=74; group C1: 120 kV, scan and reconstruction performed with 30 % ASIR, n=20; group C2: raw data from group C1 reconstructed using a blending of 50 % ASIR and 50 % FBP, n=20. The effective dose was calculated. Image quality was assessed quantitatively and qualitatively. Compared to group A, groups B1/2 and C1/2 showed a significantly reduced effective dose of 40.4 % and 73.3 % (p < 0.0001), respectively. Group B1 and group C1/2 also showed significantly reduced quantitative and qualitative image quality parameters. In group B2, quantitative measures were comparable to group A, and qualitative scores were lower compared to group A but higher compared to group B1. Diagnostic confidence grading showed groups B1/2 to be adequate for everyday clinical practice. Group C2 was considered acceptable for follow-up imaging of severe acute events such as bleeding or subacute stroke. Conclusion: Use of ASIR makes it possible to reduce radiation significantly while maintaining adequate image quality in non-contrast head CT, which may be particularly useful for younger patients in an emergency setting and in follow-up.

  19. Reducing radiation dose in adult head CT using iterative reconstruction. A clinical study in 177 patients

    International Nuclear Information System (INIS)

    Kaul, D.; Charite School of Medicine and University Hospital, Berlin; Kahn, J.; Huizing, L.; Wiener, E.; Grupp, U.; Boening, G.; Streitparth, F.; Ghadjar, P.; Renz, D.M.

    2016-01-01

    To assess how ASIR (adaptive statistical iterative reconstruction) contributes to dose reduction and affects image quality of non-contrast cranial computed tomography (cCT). Non-contrast emergency CT scans of the head acquired in 177 patients were evaluated. The scans were acquired and processed using four different protocols: Group A (control): 120 kV, FBP (filtered back projection) n=71; group B1: 120 kV, scan and reconstruction performed with 20 % ASIR (blending of 20 % ASIR and 80 % FBP), n=86; group B2: raw data from group B1 reconstructed using a blending of 40 % ASIR and 60 % FBP, n=74; group C1: 120 kV, scan and reconstruction performed with 30 % ASIR, n=20; group C2: raw data from group C1 reconstructed using a blending of 50 % ASIR and 50 % FBP, n=20. The effective dose was calculated. Image quality was assessed quantitatively and qualitatively. Compared to group A, groups B1/2 and C1/2 showed a significantly reduced effective dose of 40.4 % and 73.3 % (p < 0.0001), respectively. Group B1 and group C1/2 also showed significantly reduced quantitative and qualitative image quality parameters. In group B2, quantitative measures were comparable to group A, and qualitative scores were lower compared to group A but higher compared to group B1. Diagnostic confidence grading showed groups B1/2 to be adequate for everyday clinical practice. Group C2 was considered acceptable for follow-up imaging of severe acute events such as bleeding or subacute stroke. Conclusion: Use of ASIR makes it possible to reduce radiation significantly while maintaining adequate image quality in non-contrast head CT, which may be particularly useful for younger patients in an emergency setting and in follow-up.

  20. Proton Minibeam Radiation Therapy Reduces Side Effects in an In Vivo Mouse Ear Model

    Energy Technology Data Exchange (ETDEWEB)

    Girst, Stefanie, E-mail: stefanie.girst@unibw.de [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Greubel, Christoph; Reindl, Judith [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Siebenwirth, Christian [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Zlobinskaya, Olga [Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Walsh, Dietrich W.M. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Ilicic, Katarina [Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Aichler, Michaela; Walch, Axel [Research Unit Analytical Pathology, Helmholtz Zentrum München, German Research Center for Environmental Health, Oberschleißheim (Germany); and others

    2016-05-01

    Purpose: Proton minibeam radiation therapy is a novel approach to minimize normal tissue damage in the entrance channel by spatial fractionation while keeping tumor control through a homogeneous tumor dose using beam widening with an increasing track length. In the present study, the dose distributions for homogeneous broad beam and minibeam irradiation sessions were simulated. Also, in an animal study, acute normal tissue side effects of proton minibeam irradiation were compared with homogeneous irradiation in a tumor-free mouse ear model to account for the complex effects on the immune system and vasculature in an in vivo normal tissue model. Methods and Materials: At the ion microprobe SNAKE, 20-MeV protons were administered to the central part (7.2 × 7.2 mm{sup 2}) of the ear of BALB/c mice, using either a homogeneous field with a dose of 60 Gy or 16 minibeams with a nominal 6000 Gy (4 × 4 minibeams, size 0.18 × 0.18 mm{sup 2}, with a distance of 1.8 mm). The same average dose was used over the irradiated area. Results: No ear swelling or other skin reactions were observed at any point after minibeam irradiation. In contrast, significant ear swelling (up to fourfold), erythema, and desquamation developed in homogeneously irradiated ears 3 to 4 weeks after irradiation. Hair loss and the disappearance of sebaceous glands were only detected in the homogeneously irradiated fields. Conclusions: These results show that proton minibeam radiation therapy results in reduced adverse effects compared with conventional homogeneous broad-beam irradiation and, therefore, might have the potential to decrease the incidence of side effects resulting from clinical proton and/or heavy ion therapy.

  1. A custom-made mouthpiece incorporating tongue depressors and elevators to reduce radiation-induced tongue mucositis during carbon-ion radiation therapy for head and neck cancer.

    Science.gov (United States)

    Ikawa, Hiroaki; Koto, Masashi; Ebner, Daniel K; Takagi, Ryo; Hayashi, Kazuhiko; Tsuji, Hiroshi; Kamada, Tadashi

    We introduce a custom-made mouthpiece for carbon-ion radiation therapy for head and neck malignancy. The mouthpiece incorporates either a tongue depressor or elevator depending on tumor location. The risk of tongue mucositis may be reduced without compromising therapeutic efficacy through mouthpiece shaping. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Potent corticosteroid cream (mometasone furoate) significantly reduces acute radiation dermatitis: results from a double-blind, randomized study

    International Nuclear Information System (INIS)

    Bostroem, Aasa; Lindman, Henrik; Swartling, Carl; Berne, Berit; Bergh, Jonas

    2001-01-01

    Purpose: Radiation-induced dermatitis is a very common side effect of radiation therapy, and may necessitate interruption of the therapy. There is a substantial lack of evidence-based treatments for this condition. The aim of this study was to investigate the effect of mometasone furoate cream (MMF) on radiation dermatitis in a prospective, double-blind, randomized study. Material and methods: The study comprised 49 patients with node-negative breast cancer. They were operated on with sector resection and scheduled for postoperative radiotherapy using photons with identical radiation qualities and dosage to the breast parenchyma. The patients were randomized to receive either MMF or emollient cream. The cream was applied on the irradiated skin twice a week from the start of radiotherapy until the 12th fraction (24 Gy) and thereafter once daily until 3 weeks after completion of radiation. Both groups additionally received non-blinded emollient cream daily. The intensity of the acute radiation dermatitis was evaluated on a weekly basis regarding erythema and pigmentation, using a reflectance spectrophotometer together with visual scoring of the skin reactions. Results: MMF in combination with emollient cream treatment significantly decreased acute radiation dermatitis (P=0.0033) compared with emollient cream alone. There was no significant difference in pigmentation between the two groups. Conclusions: Adding MMF, a potent topical corticosteroid, to an emollient cream is statistically significantly more effective than emollient cream alone in reducing acute radiation dermatitis

  3. Reduced growth of soybean seedlings after exposure to weak microwave radiation from GSM 900 mobile phone and base station.

    Science.gov (United States)

    Halgamuge, Malka N; Yak, See Kye; Eberhardt, Jacob L

    2015-02-01

    The aim of this work was to study possible effects of environmental radiation pollution on plants. The association between cellular telephone (short duration, higher amplitude) and base station (long duration, very low amplitude) radiation exposure and the growth rate of soybean (Glycine max) seedlings was investigated. Soybean seedlings, pre-grown for 4 days, were exposed in a gigahertz transverse electromagnetic cell for 2 h to global system for mobile communication (GSM) mobile phone pulsed radiation or continuous wave (CW) radiation at 900 MHz with amplitudes of 5.7 and 41 V m(-1) , and outgrowth was studied one week after exposure. The exposure to higher amplitude (41 V m(-1)) GSM radiation resulted in diminished outgrowth of the epicotyl. The exposure to lower amplitude (5.7 V m(-1)) GSM radiation did not influence outgrowth of epicotyl, hypocotyls, or roots. The exposure to higher amplitude CW radiation resulted in reduced outgrowth of the roots whereas lower CW exposure resulted in a reduced outgrowth of the hypocotyl. Soybean seedlings were also exposed for 5 days to an extremely low level of radiation (GSM 900 MHz, 0.56 V m(-1)) and outgrowth was studied 2 days later. Growth of epicotyl and hypocotyl was found to be reduced, whereas the outgrowth of roots was stimulated. Our findings indicate that the observed effects were significantly dependent on field strength as well as amplitude modulation of the applied field. © 2015 Wiley Periodicals, Inc.

  4. Advanced methodologies of evaluating the radiation sources and ionising radiation shieldings for reducing the irradiation in nuclear field personnel

    International Nuclear Information System (INIS)

    Pantazi, D.; Mateescu, S.; Stanciu, M.

    2003-01-01

    One of the technical measures of protection against ionizing radiations is the radiation shielding. The process of implementing modern and efficient methods of evaluating the radiation shielding implies advanced calculation methods. That means using from simpler 1-D or 2-D computing codes such as MicroShield or QAD up to systems of codes such as SCALE (containing several independent modules) or the Monte Carlo multipurpose and many particles, MCNP, transport code. The main objective of this work is to present the Monte Carlo based evaluation of the dose rates from the CANDU type spent fuel all along the path of its handling up to intermediate storage. These values will be then compared with the values obtained from calculations with different computing programs. To obtain this objective two problems were approached: - establishing geometrical models according to the definition used by MCNP code so that the characteristics of CANDU type nuclear fuel are taking into account; - checking the validity of the proposed models by comparing the MCNP results with those obtained with other computing codes specific for shielding evaluation and radiation dose calculation

  5. Great Lakes

    Science.gov (United States)

    Edsall, Thomas A.; Mac, Michael J.; Opler, Paul A.; Puckett Haecker, Catherine E.; Doran, Peter D.

    1998-01-01

    The Great Lakes region, as defined here, includes the Great Lakes and their drainage basins in Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, and New York. The region also includes the portions of Minnesota, Wisconsin, and the 21 northernmost counties of Illinois that lie in the Mississippi River drainage basin, outside the floodplain of the river. The region spans about 9º of latitude and 20º of longitude and lies roughly halfway between the equator and the North Pole in a lowland corridor that extends from the Gulf of Mexico to the Arctic Ocean.The Great Lakes are the most prominent natural feature of the region (Fig. 1). They have a combined surface area of about 245,000 square kilometers and are among the largest, deepest lakes in the world. They are the largest single aggregation of fresh water on the planet (excluding the polar ice caps) and are the only glacial feature on Earth visible from the surface of the moon (The Nature Conservancy 1994a).The Great Lakes moderate the region’s climate, which presently ranges from subarctic in the north to humid continental warm in the south (Fig. 2), reflecting the movement of major weather masses from the north and south (U.S. Department of the Interior 1970; Eichenlaub 1979). The lakes act as heat sinks in summer and heat sources in winter and are major reservoirs that help humidify much of the region. They also create local precipitation belts in areas where air masses are pushed across the lakes by prevailing winds, pick up moisture from the lake surface, and then drop that moisture over land on the other side of the lake. The mean annual frost-free period—a general measure of the growing-season length for plants and some cold-blooded animals—varies from 60 days at higher elevations in the north to 160 days in lakeshore areas in the south. The climate influences the general distribution of wild plants and animals in the region and also influences the activities and distribution of the human

  6. Global warming likely reduces crop yield and water availability of the dryland cropping systems in the U.S. central Great Plains

    Science.gov (United States)

    We investigated impacts of GCM-projected climate change on dryland crop rotations of wheat-fallow and wheat-corn-fallow in the Central Great Plains (Akron in Colorado, USA) using the CERES 4.0 crop modules in RZWQM2. The climate change scenarios for CO2, temperature, and precipitation were produced ...

  7. Effects of growth reducer and nitrogen fertilization on morphological variables, SPAD index, interception of radiation and productivity of wheat

    Directory of Open Access Journals (Sweden)

    Elvis Felipe Elli

    2015-12-01

    Full Text Available ABSTRACT The objective of this study was to evaluate the effect of growth reducer and nitrogen fertilization on morphological variables, SPAD index, radiation interception, and grain yield of three cultivars of wheat. The experimental design was a randomized block in factorial scheme 3x5x2, with three cultivars (Mestre, Iguaçú and Itaipú, five nitrogen doses (0, 40, 80, 120, 160 Kg ha-1, and application or no application of a growth reducer, with three replications. The following characteristics were evaluated: plant height, SPAD index, leaf area index (LAI, Global Radiation Interception (GRI and grain yield. The Tukey test (p < 0.05 was used for the comparison between the means of cultivar and growth reducer factors, and for a regression analysis to evaluate N levels. Increasing the dose of nitrogen promotes an increase in LAI of plants of wheat crops differently among cultivars, which leads to a greater degree of global radiation interception. At doses higher or equal to 120 Kg ha-1 of nitrogen, there are significant differences in grain yield between treatments with and without the application of the growth reducer. The significant interaction between growth reducer and nitrogen dose, showed that applications of growth reducer increase the GRI at doses above and below 80 Kg ha-1 of nitrogen. Nitrogen rates of 138 and 109 Kg ha-1 are responsible for maximum grain yields of wheat, which is 4235 and 3787 Kg ha-1 with and without the use of growth reducer, respectively.

  8. Radiation

    International Nuclear Information System (INIS)

    2013-01-01

    The chapter one presents the composition of matter and atomic theory; matter structure; transitions; origin of radiation; radioactivity; nuclear radiation; interactions in decay processes; radiation produced by the interaction of radiation with matter

  9. Improving patient follow-up in interventional radiology and radiation-based acts. To reduce the risk of deterministic effects

    International Nuclear Information System (INIS)

    Etard, Cecile; Aubert, Bernard; Lafont, Marielle; Mougniot, Sandrine; Rousse, Carole; Bey, Eric; Cassagnes, Lucie; Guersen, Joel; Ducou Le Pointe, Hubert; Elhadad, Simon; Georges, Jean-Louis; Nonent, Michel; Paisant-Thouveny, Francine; Salvat, Cecile; Vidal, Vincent; Chauvet, Bruno; Riu, Jean-Luc; Voix, Fabien; Bar, Olivier; Le Du, Dominique; Maccia, Carlo; Lacombe, Pascal; Mertz, Luc; Valery, Charles

    2014-04-01

    After having presented an example of adverse reaction to interventional radiology (a case of a iatrogenic radiodermatitis), this report first presents the context which creates a risk situation. It describes risks related to the use of ionizing radiations, identifies risk factors and how to make procedures safer, and indicates actions aimed at reducing risks (in a preventive way, in recovery, by attenuation)

  10. Low salinity and high-level UV-B radiation reduce single-cell activity in antarctic sea ice bacteria.

    Science.gov (United States)

    Martin, Andrew; Hall, Julie; Ryan, Ken

    2009-12-01

    Experiments simulating the sea ice cycle were conducted by exposing microbes from Antarctic fast ice to saline and irradiance regimens associated with the freeze-thaw process. In contrast to hypersaline conditions (ice formation), the simulated release of bacteria into hyposaline seawater combined with rapid exposure to increased UV-B radiation significantly reduced metabolic activity.

  11. Effects of reducing the ambient UV-B radiation in the high Arctic on Salix arctica and Vaccinium uliginosum

    DEFF Research Database (Denmark)

    Albert, K.R.; Ro-Poulsen, H.; Mikkelsen, Teis Nørgaard

    2005-01-01

    , transmitting λ > 400 nm) were used to reduce UV-B radiation and UV-B+A respectively. A UV transparent film (Teflon, transmitting λ > 280 nm) and no film were used as controls. Field measurements showed that the plants under Teflon, Mylar and Lexan received app. 91%, 39% and 17% of the ambient UV-B irradiance...

  12. Beneficial effects of solar UV-B radiation on soybean yield mediated by reduced insect herbivory under field conditions.

    Science.gov (United States)

    Mazza, Carlos A; Giménez, Patricia I; Kantolic, Adriana G; Ballaré, Carlos L

    2013-03-01

    Ultraviolet-B radiation (UV-B: 280-315 nm) has damaging effects on cellular components and macromolecules. In plants, natural levels of UV-B can reduce leaf area expansion and growth, which can lead to reduced productivity and yield. UV-B can also have important effects on herbivorous insects. Owing to the successful implementation of the Montreal Protocol, current models predict that clear-sky levels of UV-B radiation will decline during this century in response to ozone recovery. However, because of climate change and changes in land use practices, future trends in UV doses are difficult to predict. In the experiments reported here, we used an exclusion approach to study the effects of solar UV-B radiation on soybean crops, which are extensively grown in many areas of the world that may be affected by future variations in UV-B radiation. In a first experiment, performed under normal management practices (which included chemical pest control), we found that natural levels of UV-B radiation reduced soybean yield. In a second experiment, where no pesticides were applied, we found that solar UV-B significantly reduced insect herbivory and, surprisingly, caused a concomitant increase in crop yield. Our data support the idea that UV-B effects on agroecosystems are the result of complex interactions involving multiple trophic levels. A better understanding of the mechanisms that mediate the anti-herbivore effect of UV-B radiation may be used to design crop varieties with improved adaptation to the cropping systems that are likely to prevail in the coming decades in response to agricultural intensification. Copyright © Physiologia Plantarum 2012.

  13. MO-G-18A-01: Radiation Dose Reducing Strategies in CT, Fluoroscopy and Radiography

    International Nuclear Information System (INIS)

    Mahesh, M; Gingold, E; Jones, A

    2014-01-01

    Advances in medical x-ray imaging have provided significant benefits to patient care. According to NCRP 160, there are more than 400 million x-ray procedures performed annually in the United States alone that contributes to nearly half of all the radiation exposure to the US population. Similar growth trends in medical x-ray imaging are observed worldwide. Apparent increase in number of medical x-ray imaging procedures, new protocols and the associated radiation dose and risk has drawn considerable attention. This has led to a number of technological innovations such as tube current modulation, iterative reconstruction algorithms, dose alerts, dose displays, flat panel digital detectors, high efficient digital detectors, storage phosphor radiography, variable filters, etc. that are enabling users to acquire medical x-ray images at a much lower radiation dose. Along with these, there are number of radiation dose optimization strategies that users can adapt to effectively lower radiation dose in medical x-ray procedures. The main objectives of this SAM course are to provide information and how to implement the various radiation dose optimization strategies in CT, Fluoroscopy and Radiography. Learning Objectives: To update impact of technological advances on dose optimization in medical imaging. To identify radiation optimization strategies in computed tomography. To describe strategies for configuring fluoroscopic equipment that yields optimal images at reasonable radiation dose. To assess ways to configure digital radiography systems and recommend ways to improve image quality at optimal dose

  14. Comparison of Techniques to Reduce Bremsstrahlung Background Radiation from Monoenergetic Photon Beams

    International Nuclear Information System (INIS)

    Johnson, M; McNabb, D

    2006-01-01

    An important applied technology is a tunable mono-energetic photon source [1]. These sources are made of relativistic electron accelerators coupled to low-energy lasers, which produce high-energy, mono-energetic-rays. One challenge associated with systems such as this is a continuum of bremsstrahlung background created when an electron beam passes through an aperture of some sort and the electron bunch or its halo impinges on the aperture pictured in figure 1. For instance, in the current T-REX [1] design for the interaction point between the laser- and electron-beam, the electron-beam passes through the center of a mirror used to reflect the laser. There is a potential with this design that bremsstrahlung radiation may be produced at the edges of the mirror openings and contaminate the mono-energetic photon beam. Certain applications [2] may be sensitive to this contamination. To reduce the bremsstrahlung contaminate a collimator (thickness ∼24in. (calculated from XCOM database [3]) to attenuate by a factor of 10 -3 the 112MeV photons expected in the T-REX demonstration [1]) is situated between the aperture and target. To maximize the brightness of the photon-beam, the collimator opening must be no less than the size of the photon-beam spot size expected to be about 1mm. This fixes the collimator opening. a priori the aperture size must be greater than the collimator opening and is a function distance between the aperture and collimator. In this paper we focus on two approaches to estimate the aperture size, given a collimator and a target whose sizes and distances from the aperture are given. In the next section we will discuss these approaches

  15. An evaluation of early countermeasures to reduce the risk of internal radiation exposure after the Fukushima nuclear incident in Japan.

    Science.gov (United States)

    Nomura, Shuhei; Tsubokura, Masaharu; Gilmour, Stuart; Hayano, Ryugo S; Watanabe, Yuni N; Kami, Masahiro; Kanazawa, Yukio; Oikawa, Tomoyoshi

    2016-05-01

    After a radiation-release incident, intake of radionuclides in the initial stage immediately following the incident may be the major contributor to total internal radiation exposure for individuals in affected areas. However, evaluation of early internal contamination risk is greatly lacking. This study assessed the relationship between initial stage evacuation/indoor sheltering and internal radiation contamination levels 4 months after the 2011 Fukushima nuclear incident in Japan and estimated potential pathways of the contamination. The study population comprised 525 participants in the internal radiation screening program at Minamisoma Municipal General Hospital, 23 km north of the Fukushima nuclear plant. The analysed dataset included the results of a screening performed in July 2011, 4 months after the incident, and of a questionnaire on early-incident response behaviours, such as sheltering indoors and evacuations, completed by participants. Association between such early countermeasures and internal contamination levels of cesium-134 were assessed using Tobit multiple regression analyses. Our study shows that individuals who evacuated to areas outside Fukushima Prefecture had similar contamination levels of cesium-134 to individuals who stayed in Fukushima (relative risk: 0.86; 95% confidence interval: 0.74-0.99). Time spent outdoors had no significant relationship with contamination levels. The effects of inhalation from radiological plumes released from the nuclear plant on total internal radiation contamination might be so low as to be undetectable by the whole-body counting unit used to examine participants. Given the apparent limited effectiveness of evacuation and indoor sheltering on internal contamination, the decision to implement such early responses to a radiation-release incident should be made by carefully balancing their potential benefits and health risks. © The Author 2015. Published by Oxford University Press. All rights reserved. For

  16. Cellular and molecular research to reduce uncertainties in estimates of health effects from low-level radiation

    Energy Technology Data Exchange (ETDEWEB)

    Elkind, M.M.; Bedford, J.; Benjamin, S.A.; Waldren, C.A. (Colorado State Univ., Fort Collins, CO (USA)); Gotchy, R.L. (Science Applications International Corp., McLean, VA (USA))

    1990-10-01

    A study was undertaken by five radiation scientists to examine the feasibility of reducing the uncertainties in the estimation of risk due to protracted low doses of ionizing radiation. In addressing the question of feasibility, a review was made by the study group: of the cellular, molecular, and mammalian radiation data that are available; of the way in which altered oncogene properties could be involved in the loss of growth control that culminates in tumorigenesis; and of the progress that had been made in the genetic characterizations of several human and animal neoplasms. On the basis of this analysis, the study group concluded that, at the present time, it is feasible to mount a program of radiation research directed at the mechanism(s) of radiation-induced cancer with special reference to risk of neoplasia due to protracted, low doses of sparsely ionizing radiation. To implement a program of research, a review was made of the methods, techniques, and instruments that would be needed. This review was followed by a survey of the laboratories and institutions where scientific personnel and facilities are known to be available. A research agenda of the principal and broad objectives of the program is also discussed. 489 refs., 21 figs., 14 tabs.

  17. Cellular and molecular research to reduce uncertainties in estimates of health effects from low-level radiation

    International Nuclear Information System (INIS)

    Elkind, M.M.; Bedford, J.; Benjamin, S.A.; Waldren, C.A.; Gotchy, R.L.

    1990-10-01

    A study was undertaken by five radiation scientists to examine the feasibility of reducing the uncertainties in the estimation of risk due to protracted low doses of ionizing radiation. In addressing the question of feasibility, a review was made by the study group: of the cellular, molecular, and mammalian radiation data that are available; of the way in which altered oncogene properties could be involved in the loss of growth control that culminates in tumorigenesis; and of the progress that had been made in the genetic characterizations of several human and animal neoplasms. On the basis of this analysis, the study group concluded that, at the present time, it is feasible to mount a program of radiation research directed at the mechanism(s) of radiation-induced cancer with special reference to risk of neoplasia due to protracted, low doses of sparsely ionizing radiation. To implement a program of research, a review was made of the methods, techniques, and instruments that would be needed. This review was followed by a survey of the laboratories and institutions where scientific personnel and facilities are known to be available. A research agenda of the principal and broad objectives of the program is also discussed. 489 refs., 21 figs., 14 tabs

  18. A programme to reduce down-time and site radiation dose through improvements in control rod design

    International Nuclear Information System (INIS)

    Izatt, J.A.; Scobie, J.

    1983-01-01

    In many nuclear facilities a high proportion of the total radiation dose to staff may be ascribed to very few routine operations. Often this critical operation will require significant shut-down time, both to perform the function itself and to allow sufficient decay time to reduce radiation levels to acceptable values. This situation arises on the UTR-300 reactor at S.U.R.R.C., where over the twenty years of operation it has been found necessary to carry out preventive, and on some occasions remedial, maintenance at least once per year on the in-core elements of the control rod assemblies. This had led inevitably to reduced availability of the reactor and to significant overall radiation doses to the few long-serving staff members who carry out this work. The source of the problem seems to lie in the basic design of the assemblies, which may have been adequate for the original 10 KW versions of this reactor, but has proven to be deficient in several respects at the present 300 KW operating level. In an attempt to reduce down-time and radiation dose to staff a radical re-design of the control assemblies was undertaken in-house, and a conversion programme has been underway over the last two years. Details of the design improvements are presented with a discussion of the operating experience to date. (author)

  19. The use of adaptive radiation therapy to reduce setup error: a prospective clinical study

    International Nuclear Information System (INIS)

    Yan Di; Wong, John; Vicini, Frank; Robertson, John; Horwitz, Eric; Brabbins, Donald; Cook, Carla; Gustafson, Gary; Stromberg, Jannifer; Martinez, Alvaro

    1996-01-01

    Purpose: Adaptive Radiation Therapy (ART) is a closed-loop feedback process where each patients treatment is adaptively optimized according to the individual variation information measured during the course of treatment. The process aims to maximize the benefits of treatment for the individual patient. A prospective study is currently being conducted to test the feasibility and effectiveness of ART for clinical use. The present study is limited to compensating the effects of systematic setup error. Methods and Materials: The study includes 20 patients treated on a linear accelerator equipped with a computer controlled multileaf collimator (MLC) and a electronic portal imaging device (EPID). Alpha cradles are used to immobilize those patients treated for disease in the thoracic and abdominal regions, and thermal plastic masks for the head and neck. Portal images are acquired daily. Setup error of each treatment field is quantified off-line every day. As determined from an earlier retrospective study of different clinical sites, the measured setup variation from the first 4 to 9 days, are used to estimate systematic setup error and the standard deviation of random setup error for each field. Setup adjustment is made if estimated systematic setup error of the treatment field was larger than or equal to 2 mm. Instead of the conventional approach of repositioning the patient, setup correction is implemented by reshaping MLC to compensate for the estimated systematic error. The entire process from analysis of portal images to the implementation of the modified MLC field is performed via computer network. Systematic and random setup errors of the treatment after adjustment are compared with those prior to adjustment. Finally, the frequency distributions of block overlap cumulated throughout the treatment course are evaluated. Results: Sixty-seven percent of all treatment fields were reshaped to compensate for the estimated systematic errors. At the time of this writing

  20. Radiation protection for nurses. Regulations and guidelines

    International Nuclear Information System (INIS)

    Jankowski, C.B.

    1992-01-01

    Rules and regulations of federal agencies and state radiation protection programs provide the bases for hospital policy regarding radiation safety for nurses. Nursing administrators should work with the radiation safety officer at their institutions to ensure that radiation exposures to staff nurses will be as low as reasonably achievable and that special consideration will be given to pregnant nurses. Nurses' fears about their exposure to radiation can be greatly reduced through education

  1. Efficacy of RADPAD® protection drape in reducing radiation exposure to the primary operator during Transcatheter Aortic Valve Implantation (TAVI).

    Science.gov (United States)

    Sharma, Divyesh; Ramsewak, Adesh; Manoharan, Ganesh; Spence, Mark S

    2016-02-01

    The efficacy of RADPAD® (a sterile, lead-free drape) has been demonstrated to reduce the scatter radiation to the primary operator during fluoroscopic procedures. However, the use of the RADPAD® during TAVI procedures has not been studied. Transcatheter aortic valve implantation (TAVI) is now an established treatment for patients with symptomatic severe aortic stenosis who are deemed inoperable or at high risk for conventional surgical aortic valve replacement (AVR). Consequently the radiation exposure to the patient and the interventional team from this procedure has become a matter of interest and importance. Methods to reduce radiation exposure to the interventional team during this procedure should be actively investigated. In this single center prospective study, we determined the radiation dose during this procedure and the efficacy of RADPAD® in reducing the radiation dose to the primary operator. Fifty consecutive patients due to undergo elective TAVI procedures were identified. Patients were randomly assigned to undergo the procedure with or without the use of a RADPAD® drape. There were 25 patients in each group and dosimetry was performed at the left eye level of the primary operator. The dosimeter was commenced at the start of the procedure, and the dose was recorded immediately after the end of the procedure. Fluoroscopy times and DAP were also recorded prospectively. Twenty-five patients underwent transfemoral TAVI using a RADPAD® and 25 with no-RADPAD®. The mean primary operator radiation dose was significantly lower in the RADPAD group at 14.8 mSv vs. 24.3 mSv in the no-RADPAD group (P=0.008). There was no significant difference in fluoroscopy times or dose-area products between the two patient groups. The dose to the primary operator relative to fluoroscopy time (RADPAD: slope=0.325; no RADPAD: slope=1.148; analysis of covariance F=7.47, P=0.009) and dose area product (RADPAD: slope=0.0007; no RADPAD: slope=0.002; analysis of covariance F=7

  2. Development and demonstration of techniques for reducing occupational radiation doses during refueling outages. Tasks 7A/7B. Advanced outage management and radiation exposure control

    International Nuclear Information System (INIS)

    1985-03-01

    Objectives of Tasks 7A and 7B were to develop and demonstrate computer based systems to assist plant management and staff in utilizing information more effectively to reduce occupational exposures received as a result of refueling outages, and to shorten the duration of the outage. The Advanced Outage Management (AOM) Tool (Task 7A) is an automated outage planning system specifically designed to meet the needs of nuclear plant outage management. The primary objective of the AOM tool is to provide a computerized system that can manipulate the information typically associated with outage planning and scheduling to furnish reports and schedules that more accurately project the future course of the outage. The Radiation Exposure Control (REC) Tool (Task 7B) is a computerized personnel radiation exposure accounting and management system designed to enable nuclear plant management to project and monitor total personnel radiation exposure on a real-time basis. The two systems were designed to operate on the same computer system and interface through a common database that enables information sharing between plant organizations not typically interfaced. This interfacing provides outage planners with a means of incorporating occupational radiation exposure as a factor for making decisions on the course of an outage

  3. Ionizing radiation-induced phosphorylation of RPA p34 is deficient in ataxia telangiectasia and reduced in aged normal fibroblasts

    International Nuclear Information System (INIS)

    Xinbo Cheng; Nge Cheong; Ya Wang; Iliakis, George

    1996-01-01

    Replication protein A (RPA, also called human single stranded DNA binding protein, hSSB) is a trimeric, multifunctional protein complex involved in DNA replication, DNA repair and recombination. Phosphorylation of RPA p34 subunit is observed after exposure of cells to radiation and other DNA damaging agents, which implicates the protein not only in repair but also in the regulation of replication on damaged DNA template. Here, we show that the phosphorylation observed in RPA p34 after exposure to ionizing radiation, X- or γ-rays, is reduced and occurs later in primary fibroblasts from patients suffering from ataxia telangiectasia (AT), as compared to normal fibroblasts. We also show that in primary normal human fibroblasts, radiation-induced phosphorylation of RPA p34 is 'age'-dependent and decreases significantly as cultures senesce. Radiation-induced phosphorylation of RPA p34 is nearly absent in non-cycling cells, while the expression of p21 cip1/waf1/sdi1 remains inducible. The results demonstrate a growth-stage and culture-age dependency in radiation-induced RPA p34 phosphorylation, and suggest the operation of a signal transduction pathway that is inactivated in senescing or quiescent fibroblasts and defective in AT cells

  4. Meeting Radiation Protection Requirements and Reducing Spacecraft Mass - A Multifunctional Materials Approach

    Science.gov (United States)

    Atwell, William; Koontz, Steve; Reddell, Brandon; Rojdev, Kristina; Franklin, Jennifer

    2010-01-01

    Both crew and radio-sensitive systems, especially electronics must be protected from the effects of the space radiation environment. One method of mitigating this radiation exposure is to use passive-shielding materials. In previous vehicle designs such as the International Space Station (ISS), materials such as aluminum and polyethylene have been used as parasitic shielding to protect crew and electronics from exposure, but these designs add mass and decrease the amount of usable volume inside the vehicle. Thus, it is of interest to understand whether structural materials can also be designed to provide the radiation shielding capability needed for crew and electronics, while still providing weight savings and increased useable volume when compared against previous vehicle shielding designs. In this paper, we present calculations and analysis using the HZETRN (deterministic) and FLUKA (Monte Carlo) codes to investigate the radiation mitigation properties of these structural shielding materials, which includes graded-Z and composite materials. This work is also a follow-on to an earlier paper, that compared computational results for three radiation transport codes, HZETRN, HETC, and FLUKA, using the Feb. 1956 solar particle event (SPE) spectrum. In the following analysis, we consider the October 1989 Ground Level Enhanced (GLE) SPE as the input source term based on the Band function fitting method. Using HZETRN and FLUKA, parametric absorbed doses at the center of a hemispherical structure on the lunar surface are calculated for various thicknesses of graded-Z layups and an all-aluminum structure. HZETRN and FLUKA calculations are compared and are in reasonable (18% to 27%) agreement. Both codes are in agreement with respect to the predicted shielding material performance trends. The results from both HZETRN and FLUKA are analyzed and the radiation protection properties and potential weight savings of various materials and materials lay-ups are compared.

  5. Increased UV-B radiation reduces N2-fixation in tropical leguminous crops

    International Nuclear Information System (INIS)

    Anupa Singh

    1997-01-01

    Net photosynthesis, leaf area, biomass, and number, size and activity of nodules were examined in three leguminous plants subjected under field conditions to supplemental UV-B radiation equivalent to a 15% ozone depletion at 25 degrees N latitude. Enhanced UV-B radiation adversely affected the net photosynthetic rate, growth characteristics and nodule activity in all three species. Maximum reduction in net photosynthesis occurred in Phaseolus mungo cv. Pant U-30, whereas the greatest reduction in nitrogenase activity occurred in Vigna radiata. (author)

  6. Does sucralfate reduce early side effects of pelvic radiation? A double-blind randomized trial.

    Science.gov (United States)

    Stellamans, Karin; Lievens, Yolande; Lambin, Philippe; Van den Weyngaert, Danielle; Van den Bogaert, Walter; Scalliet, Pierre; Hutsebaut, Liesbeth; Haustermans, Karin

    2002-11-01

    STUDY AND METHODS: A double-blind placebo-controlled study randomized 108 patients to investigate the effect of sucralfate on gastrointestinal side effects of pelvic radiation. Overall, pelvic radiation with the administered doses and fields and performed according to nowadays technical standards, was well tolerated. Comparison of the mean scores and the peak reactions for radiotherapy discomfort, diarrhoea and number of stools per day in the 80 evaluable patients showed no statistically significant difference between sucralfate and placebo. Based on these results, the use of sucralfate can not be recommended as standard practice.

  7. Does sucralfate reduce early side effects of pelvic radiation? A double-blind randomized trial

    International Nuclear Information System (INIS)

    Stellamans, Karin; Lievens, Yolande; Lambin, Philippe; Van den Weyngaert, Danielle; Van den Bogaert, Walter; Scalliet, Pierre; Hutsebaut, Liesbeth; Haustermans, Karin

    2002-01-01

    Study and methods: A double-blind placebo-controlled study randomized 108 patients to investigate the effect of sucralfate on gastrointestinal side effects of pelvic radiation. Results: Overall, pelvic radiation with the administered doses and fields and performed according to nowadays technical standards, was well tolerated. Comparison of the mean scores and the peak reactions for radiotherapy discomfort, diarrhoea and number of stools per day in the 80 evaluable patients showed no statistically significant difference between sucralfate and placebo. Conclusion: Based on these results, the use of sucralfate can not be recommended as standard practice

  8. A programme to reduce down-time and site radiation dose through improvements in control rod design

    International Nuclear Information System (INIS)

    Izatt, J.A.; Scobie, J.

    1985-01-01

    On the UTR-300 reactor at SURRC, it has been found necessary to carry out preventive or remedial maintenance at least once per year on the in-core elements of the control rod assemblies. This has led to reduced availability of the reactor and to significant overall radiation doses to the few long-serving staff members who carry out this work. In an attempt to reduce down-time and radiation dose to staff a radical re-design of the control assemblies was undertaken in-house, and a conversion programme has been underway over the last four years. Details of the design improvements are presented together with a discussion of the operating experience to date. (author)

  9. Maternal exposure to Great Lakes sport-caught fish and dichlorodiphenyl dichloroethylene, but not polychlorinated biphenyls, is associated with reduced birth weight

    International Nuclear Information System (INIS)

    Weisskopf, M.G.; Anderson, H.A.; Hanrahan, L.P.; Kanarek, M.S.; Falk, C.M.; Steenport, D.M.; Draheim, L.A.

    2005-01-01

    Fish consumption may be beneficial for a developing human fetus, but fish may also contain contaminants that could be detrimental. Great Lakes sport-caught fish (GLSCF) are contaminated with polychlorinated biphenyls (PCBs) and dichlorodiphenyl dichloroethylene (DDE), but the effects of these contaminants on birth outcome are not clear. To distinguish potential contaminant effects, we examined (1) whether the decrease over time in contaminant levels in GLSCF is paralleled by an increase in birth weight of children of GLSCF-consuming mothers and (2) the relation between maternal serum concentrations of these contaminants and birth weight. Mothers (n=511) were interviewed from 1993 to 1995, and maternal serum was collected from 1994 to 1995 (n=143). Potential confounders considered were child gender, maternal age at delivery, maternal prepregnancy body mass index, maternal cigarette and alcohol use during pregnancy, maternal education level, maternal parity, and maternal breastfeeding. Children born during 1970-1977, 1978-1984, and 1985-1993 to mothers who ate more than 116 meals of GLSCF before pregnancy were, on average, 164 g lighter, 46 g heavier, and 134 g heavier, respectively, than children of mothers who ate no GLSCF before pregnancy (P trend=0.05). GLSCF-consuming mothers had higher serum PCB and DDE concentrations, but only increased DDE was associated with lower birth weight. The data suggest that fetal DDE exposure (as indicated by maternal serum DDE concentration) may decrease birth weight and that decreased birth weight effects associated with GLSCF consumption have decreased over time

  10. Effect of radiation therapy on small-cell lung cancer is reduced by ubiquinone intake

    DEFF Research Database (Denmark)

    Lund, E L; Quistorff, B; Spang-Thomsen, M

    1998-01-01

    radiation dose of 5 Gy, using a 300 kV therapeutic unit. The macroscopic growth pre- and posttreatment was analyzed according to a transformed Gompertz algorithm using the software program GROWTH. Treatment with Q10 or soy oil alone had no effect on tumor growth compared with untreated controls. Groups...

  11. Effects of growth reducer and nitrogen fertilization on morphological variables, SPAD index, interception of radiation and productivity of wheat

    OpenAIRE

    Elvis Felipe Elli; Braulio Otomar Caron; Sandro Luis Petter Medeiros; Elder Eloy; Gean Charles Monteiro; Denise Schmidt

    2015-01-01

    ABSTRACT The objective of this study was to evaluate the effect of growth reducer and nitrogen fertilization on morphological variables, SPAD index, radiation interception, and grain yield of three cultivars of wheat. The experimental design was a randomized block in factorial scheme 3x5x2, with three cultivars (Mestre, Iguaçú and Itaipú), five nitrogen doses (0, 40, 80, 120, 160 Kg ha-1), and application or no application of a growth reducer, with three replications. The following characteri...

  12. Acute radiation syndrome (ARS – treatment of the reduced host defense

    Directory of Open Access Journals (Sweden)

    Heslet L

    2012-01-01

    Full Text Available Lars Heslet1, Christiane Bay2, Steen Nepper-Christensen31Serendex ApS, Gentofte; 2University of Copenhagen, Medical Faculty, Copenhagen; 3Department of Head and Neck Surgery, Otorhinolaryngology, Køge University Hospital, Køge, DenmarkBackground: The current radiation threat from the Fukushima power plant accident has prompted rethinking of the contingency plan for prophylaxis and treatment of the acute radiation syndrome (ARS. The well-documented effect of the growth factors (granulocyte colony-stimulating factor [G-CSF] and granulocyte-macrophage colony-stimulating factor [GM-CSF] in acute radiation injury has become standard treatment for ARS in the United States, based on the fact that growth factors increase number and functions of both macrophages and granulocytes.Methods: Review of the current literature.Results: The lungs have their own host defense system, based on alveolar macrophages. After radiation exposure to the lungs, resting macrophages can no longer be transformed, not even during systemic administration of growth factors because G-CSF/GM-CSF does not penetrate the alveoli. Under normal circumstances, locally-produced GM-CSF receptors transform resting macrophages into fully immunocompetent dendritic cells in the sealed-off pulmonary compartment. However, GM-CSF is not expressed in radiation injured tissue due to defervescence of the macrophages. In order to maintain the macrophage’s important role in host defense after radiation exposure, it is hypothesized that it is necessary to administer the drug exogenously in order to uphold the barrier against exogenous and endogenous infections and possibly prevent the potentially lethal systemic infection, which is the main cause of death in ARS.Recommendation: Preemptive treatment should be initiated after suspected exposure of a radiation dose of at least ~2 Gy by prompt dosing of 250–400 µg GM-CSF/m2 or 5 µg/kg G-CSF administered systemically and concomitant inhalation of

  13. New symbol launched to warn public about radiation dangers. Supplementary symbol aims to help reduce needless deaths and injuries

    International Nuclear Information System (INIS)

    2007-01-01

    Full text: With radiating waves, a skull and crossbones and a running person, a new ionizing radiation warning symbol is being introduced to supplement the traditional international symbol for radiation, the three cornered trefoil. The new symbol is being launched today by the IAEA and the International Organization for Standardization (ISO) to help reduce needless deaths and serious injuries from accidental exposure to large radioactive sources. It will serve as a supplementary warning to the trefoil, which has no intuitive meaning and little recognition beyond those educated in its significance. 'I believe the international recognition of the specific expertise of both organizations will ensure that the new standard will be accepted and applied by governments and industry to improve the safety of nuclear applications, protection of people and the environment', said Ms. Eliana Amaral, Director, Division of Radiation, Transport and Waste Safety, IAEA. The new symbol is aimed at alerting anyone, anywhere to the potential dangers of being close to a large source of ionizing radiation, the result of a five-year project conducted in 11 countries around the world. The symbol was tested with different population groups - mixed ages, varying educational backgrounds, male and female - to ensure that its message of 'danger- stay away' was crystal clear and understood by all. 'We can't teach the world about radiation,' said Carolyn Mac Kenzie, an IAEA radiation specialist who helped develop the symbol, 'but we can warn people about dangerous sources for the price of sticker.' The new symbol, developed by human factor experts, graphic artists, and radiation protection experts, was tested by the Gallup Institute on a total of 1 650 individuals in Brazil, Mexico, Morocco, Kenya, Saudi Arabia, China, India, Thailand, Poland, Ukraine and the United States. The symbol is intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury

  14. New symbol launched to warn public about radiation dangers. Supplementary symbol aims to help reduce needless deaths and injuries

    International Nuclear Information System (INIS)

    2007-01-01

    Full text: With radiating waves, a skull and crossbones and a running person, a new ionizing radiation warning symbol is being introduced to supplement the traditional international symbol for radiation, the three cornered trefoil. The new symbol is being launched today by the IAEA and the International Organization for Standardization (ISO) to help reduce needless deaths and serious injuries from accidental exposure to large radioactive sources. It will serve as a supplementary warning to the trefoil, which has no intuitive meaning and little recognition beyond those educated in its significance. 'I believe the international recognition of the specific expertise of both organizations will ensure that the new standard will be accepted and applied by governments and industry to improve the safety of nuclear applications, protection of people and the environment', said Ms. Eliana Amaral, Director, Division of Radiation, Transport and Waste Safety, IAEA. The new symbol is aimed at alerting anyone, anywhere to the potential dangers of being close to a large source of ionizing radiation, the result of a five-year project conducted in 11 countries around the world. The symbol was tested with different population groups - mixed ages, varying educational backgrounds, male and female - to ensure that its message of 'danger- stay away' was crystal clear and understood by all. 'We can't teach the world about radiation,' said Carolyn Mac Kenzie, an IAEA radiation specialist who helped develop the symbol, 'but we can warn people about dangerous sources for the price of sticker.' The new symbol, developed by human factor experts, graphic artists, and radiation protection experts, was tested by the Gallup Institute on a total of 1 650 individuals in Brazil, Mexico, Morocco, Kenya, Saudi Arabia, China, India, Thailand, Poland, Ukraine and the United States. The symbol is intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury

  15. New symbol launched to warn public about radiation dangers. Supplementary symbol aims to help reduce needless deaths and injuries

    International Nuclear Information System (INIS)

    2007-01-01

    Full text: With radiating waves, a skull and crossbones and a running person, a new ionizing radiation warning symbol is being introduced to supplement the traditional international symbol for radiation, the three cornered trefoil. The new symbol is being launched today by the IAEA and the International Organization for Standardization (ISO) to help reduce needless deaths and serious injuries from accidental exposure to large radioactive sources. It will serve as a supplementary warning to the trefoil, which has no intuitive meaning and little recognition beyond those educated in its significance. 'I believe the international recognition of the specific expertise of both organizations will ensure that the new standard will be accepted and applied by governments and industry to improve the safety of nuclear applications, protection of people and the environment', said Ms. Eliana Amaral, Director, Division of Radiation, Transport and Waste Safety, IAEA. The new symbol is aimed at alerting anyone, anywhere to the potential dangers of being close to a large source of ionizing radiation, the result of a five-year project conducted in 11 countries around the world. The symbol was tested with different population groups - mixed ages, varying educational backgrounds, male and female - to ensure that its message of 'danger- stay away' was crystal clear and understood by all. 'We can't teach the world about radiation,' said Carolyn Mac Kenzie, an IAEA radiation specialist who helped develop the symbol, 'but we can warn people about dangerous sources for the price of sticker.' The new symbol, developed by human factor experts, graphic artists, and radiation protection experts, was tested by the Gallup Institute on a total of 1 650 individuals in Brazil, Mexico, Morocco, Kenya, Saudi Arabia, China, India, Thailand, Poland, Ukraine and the United States. The symbol is intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury

  16. New symbol launched to warn public about radiation dangers. Supplementary symbol aims to help reduce needless deaths and injuries

    International Nuclear Information System (INIS)

    2007-01-01

    Full text: With radiating waves, a skull and crossbones and a running person, a new ionizing radiation warning symbol is being introduced to supplement the traditional international symbol for radiation, the three cornered trefoil. The new symbol is being launched today by the IAEA and the International Organization for Standardization (ISO) to help reduce needless deaths and serious injuries from accidental exposure to large radioactive sources. It will serve as a supplementary warning to the trefoil, which has no intuitive meaning and little recognition beyond those educated in its significance. 'I believe the international recognition of the specific expertise of both organizations will ensure that the new standard will be accepted and applied by governments and industry to improve the safety of nuclear applications, protection of people and the environment', said Ms. Eliana Amaral, Director, Division of Radiation, Transport and Waste Safety, IAEA. The new symbol is aimed at alerting anyone, anywhere to the potential dangers of being close to a large source of ionizing radiation, the result of a five-year project conducted in 11 countries around the world. The symbol was tested with different population groups - mixed ages, varying educational backgrounds, male and female - to ensure that its message of 'danger- stay away' was crystal clear and understood by all. 'We can't teach the world about radiation,' said Carolyn Mac Kenzie, an IAEA radiation specialist who helped develop the symbol, 'but we can warn people about dangerous sources for the price of sticker.' The new symbol, developed by human factor experts, graphic artists, and radiation protection experts, was tested by the Gallup Institute on a total of 1 650 individuals in Brazil, Mexico, Morocco, Kenya, Saudi Arabia, China, India, Thailand, Poland, Ukraine and the United States. The symbol is intended for IAEA Category 1, 2 and 3 sources defined as dangerous sources capable of death or serious injury

  17. Embedded top-coat for reducing the effect out of band radiation in EUV lithography

    Science.gov (United States)

    Du, Ke; Siauw, Meiliana; Valade, David; Jasieniak, Marek; Voelcker, Nico; Trefonas, Peter; Thackeray, Jim; Blakey, Idriss; Whittaker, Andrew

    2017-03-01

    Out of band (OOB) radiation from the EUV source has significant implications for the performance of EUVL photoresists. Here we introduce a surface-active polymer additive, capable of partitioning to the top of the resist film during casting and annealing, to protect the underlying photoresist from OOB radiation. Copolymers were prepared using reversible addition-fragmentation chain transfer (RAFT) polymerization, and rendered surface active by chain extension with a block of fluoro-monomer. Films were prepared from the EUV resist with added surface-active Embedded Barrier Layer (EBL), and characterized using measurements of contact angles and spectroscopic ellipsometry. Finally, the lithographic performance of the resist containing the EBL was evaluated using Electron Beam Lithography exposure

  18. Reducing radiation exposures at nuclear power plants using virtual job planning

    International Nuclear Information System (INIS)

    Verzilov, Y.; Husain, A.

    2014-01-01

    Advanced Dose Exposure Planning Tool (ADEPT) is an innovative solution for assisting nuclear station staff to effectively minimize worker dose during inspection and maintenance activities and to improve ALARA job planning. ADEPT combines visualization and simulation of the radioactive environment at a nuclear station to estimate worker dose. It allows users to walk through a virtual job plan and receive a live radiation dose estimate for the planned work. (author)

  19. Can radiation damage to protein crystals be reduced using small-molecule compounds?

    Energy Technology Data Exchange (ETDEWEB)

    Kmetko, Jan [Kenyon College, Gambier, OH 43022 (United States); Warkentin, Matthew; Englich, Ulrich; Thorne, Robert E., E-mail: ret6@cornell.edu [Cornell University, Ithaca, NY 14853 (United States); Kenyon College, Gambier, OH 43022 (United States)

    2011-10-01

    Free-radical scavengers that are known to be effective protectors of proteins in solution are found to increase global radiation damage to protein crystals. Protective mechanisms may become deleterious in the protein-dense environment of a crystal. Recent studies have defined a data-collection protocol and a metric that provide a robust measure of global radiation damage to protein crystals. Using this protocol and metric, 19 small-molecule compounds (introduced either by cocrystallization or soaking) were evaluated for their ability to protect lysozyme crystals from radiation damage. The compounds were selected based upon their ability to interact with radiolytic products (e.g. hydrated electrons, hydrogen, hydroxyl and perhydroxyl radicals) and/or their efficacy in protecting biological molecules from radiation damage in dilute aqueous solutions. At room temperature, 12 compounds had no effect and six had a sensitizing effect on global damage. Only one compound, sodium nitrate, appeared to extend crystal lifetimes, but not in all proteins and only by a factor of two or less. No compound provided protection at T = 100 K. Scavengers are ineffective in protecting protein crystals from global damage because a large fraction of primary X-ray-induced excitations are generated in and/or directly attack the protein and because the ratio of scavenger molecules to protein molecules is too small to provide appreciable competitive protection. The same reactivity that makes some scavengers effective radioprotectors in protein solutions may explain their sensitizing effect in the protein-dense environment of a crystal. A more productive focus for future efforts may be to identify and eliminate sensitizing compounds from crystallization solutions.

  20. Can radiation damage to protein crystals be reduced using small-molecule compounds?

    International Nuclear Information System (INIS)

    Kmetko, Jan; Warkentin, Matthew; Englich, Ulrich; Thorne, Robert E.

    2011-01-01

    Free-radical scavengers that are known to be effective protectors of proteins in solution are found to increase global radiation damage to protein crystals. Protective mechanisms may become deleterious in the protein-dense environment of a crystal. Recent studies have defined a data-collection protocol and a metric that provide a robust measure of global radiation damage to protein crystals. Using this protocol and metric, 19 small-molecule compounds (introduced either by cocrystallization or soaking) were evaluated for their ability to protect lysozyme crystals from radiation damage. The compounds were selected based upon their ability to interact with radiolytic products (e.g. hydrated electrons, hydrogen, hydroxyl and perhydroxyl radicals) and/or their efficacy in protecting biological molecules from radiation damage in dilute aqueous solutions. At room temperature, 12 compounds had no effect and six had a sensitizing effect on global damage. Only one compound, sodium nitrate, appeared to extend crystal lifetimes, but not in all proteins and only by a factor of two or less. No compound provided protection at T = 100 K. Scavengers are ineffective in protecting protein crystals from global damage because a large fraction of primary X-ray-induced excitations are generated in and/or directly attack the protein and because the ratio of scavenger molecules to protein molecules is too small to provide appreciable competitive protection. The same reactivity that makes some scavengers effective radioprotectors in protein solutions may explain their sensitizing effect in the protein-dense environment of a crystal. A more productive focus for future efforts may be to identify and eliminate sensitizing compounds from crystallization solutions

  1. A statewide teleradiology system reduces radiation exposure and charges in transferred trauma patients.

    Science.gov (United States)

    Watson, Justin J J; Moren, Alexis; Diggs, Brian; Houser, Ben; Eastes, Lynn; Brand, Dawn; Bilyeu, Pamela; Schreiber, Martin; Kiraly, Laszlo

    2016-05-01

    Trauma transfer patients routinely undergo repeat imaging because of inefficiencies within the radiology system. In 2009, the virtual private network (VPN) telemedicine system was adopted throughout Oregon allowing virtual image transfer between hospitals. The startup cost was a nominal $3,000 per hospital. A retrospective review from 2007 to 2012 included 400 randomly selected adult trauma transfer patients based on a power analysis (200 pre/200 post). The primary outcome evaluated was reduction in repeat computed tomography (CT) scans. Secondary outcomes included cost savings, emergency department (ED) length of stay (LOS), and spared radiation. All data were analyzed using Mann-Whitney U and chi-square tests. P less than .05 indicated significance. Spared radiation was calculated as a weighted average per body region, and savings was calculated using charges obtained from Oregon Health and Science University radiology current procedural terminology codes. Four-hundred patients were included. Injury Severity Score, age, ED and overall LOS, mortality, trauma type, and gender were not statistically different between groups. The percentage of patients with repeat CT scans decreased after VPN implementation: CT abdomen (13.2% vs 2.8%, P < .01) and cervical spine (34.4% vs 18.2%, P < .01). Post-VPN, the total charges saved in 2012 for trauma transfer patients was $333,500, whereas the average radiation dose spared per person was 1.8 mSV. Length of stay in the ED for patients with Injury Severity Score less than 15 transferring to the ICU was decreased (P < .05). Implementation of a statewide teleradiology network resulted in fewer total repeat CT scans, significant savings, decrease in radiation exposure, and decreased LOS in the ED for patients with less complex injuries. The potential for health care savings by widespread adoption of a VPN is significant. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Analytic Shielding Optimization to Reduce Crew Exposure to Ionizing Radiation Inside Space Vehicles

    Science.gov (United States)

    Gaza, Razvan; Cooper, Tim P.; Hanzo, Arthur; Hussein, Hesham; Jarvis, Kandy S.; Kimble, Ryan; Lee, Kerry T.; Patel, Chirag; Reddell, Brandon D.; Stoffle, Nicholas; hide

    2009-01-01

    A sustainable lunar architecture provides capabilities for leveraging out-of-service components for alternate uses. Discarded architecture elements may be used to provide ionizing radiation shielding to the crew habitat in case of a Solar Particle Event. The specific location relative to the vehicle where the additional shielding mass is placed, as corroborated with particularities of the vehicle design, has a large influence on protection gain. This effect is caused by the exponential- like decrease of radiation exposure with shielding mass thickness, which in turn determines that the most benefit from a given amount of shielding mass is obtained by placing it so that it preferentially augments protection in under-shielded areas of the vehicle exposed to the radiation environment. A novel analytic technique to derive an optimal shielding configuration was developed by Lockheed Martin during Design Analysis Cycle 3 (DAC-3) of the Orion Crew Exploration Vehicle (CEV). [1] Based on a detailed Computer Aided Design (CAD) model of the vehicle including a specific crew positioning scenario, a set of under-shielded vehicle regions can be identified as candidates for placement of additional shielding. Analytic tools are available to allow capturing an idealized supplemental shielding distribution in the CAD environment, which in turn is used as a reference for deriving a realistic shielding configuration from available vehicle components. While the analysis referenced in this communication applies particularly to the Orion vehicle, the general method can be applied to a large range of space exploration vehicles, including but not limited to lunar and Mars architecture components. In addition, the method can be immediately applied for optimization of radiation shielding provided to sensitive electronic components.

  3. Modeling of Solar Radiation Management: A Comparison of Simulations Using Reduced Solar Constant and Stratospheric Sulphate Aerosols

    Science.gov (United States)

    Bala, G.; Kalidindi, S.; Modak, A.; Caldeira, K.

    2014-12-01

    Several climate modelling studies in the past have used reduction in solar constant to simulate the climatic effects of Solar Radiation Management (SRM) geoengineering. This is most likely valid only for space-based mirrors/reflectors but not for SRM methods that rely on stratospheric aerosols. In this study, we use a climate model to evaluate the differences in climate response to SRM by uniform solar constant reduction and stratospheric aerosols. The experiments are designed such that global mean warming from a doubling of atmospheric CO2 concentration (2xCO2) is nearly cancelled in each case. In such a scenario, the residual climate effects are similar when important surface and tropospheric climate variables such as temperature and precipitation are considered. However, there are significant differences in stratospheric temperature response and diffuse and direct radiation reaching the surface. A difference of 1K in the global mean stratospheric (61-9.8 hPa) temperature is simulated between the two SRM methods, with warming in the aerosol scheme and a slight cooling for sunshades. While the global mean surface diffuse radiation increases by ~23% and direct radiation decreases by about 9% in the case of aerosol SRM method, both direct and diffuse radiation decrease by similar fractional amounts (~1.0%) when solar constant is reduced. When CO2 fertilization effects from elevated CO2 concentration levels are removed, the contribution from shaded leaves to gross primary productivity (GPP) increases by 1.8 % in aerosol SRM because of increased diffuse light. However, this increase is almost offset by a 15.2% decline in sunlit contribution due to reduced direct light. Overall both the SRM simulations show similar decrease in GPP (~ 8%) and NPP (~3%) relative to 2xCO2, indicating the negligible effect of the fractional changes in direct/diffuse radiation on the overall plant productivity. Based on our modelling study, we conclude that the climate states produced by a

  4. Timing of pilocarpine treatment during head and neck radiotherapy: concomitant administration reduces xerostomia better than post-radiation pilocarpine

    International Nuclear Information System (INIS)

    Zimmerman, Robert P.; Mark, Rufus J.; Juillard, Guy F.

    1996-01-01

    Purpose: To study whether oral pilocarpine administration during and three months after head and neck radiotherapy can prevent or reduce the expected post-radiation xerostomia. This regimen was compared to no treatment and to post-radiotherapy pilocarpine administration, which has previously been shown to reduce symptoms of xerostomia in several randomized trials. Methods: Xerostomia assessments were performed using a visual analog scale xerostomia questionnaire that measures oral dryness, oral comfort, difficulty with sleep, speech and eating. Higher scores indicate less xerostomia. All the patients had all major salivary glands in the initial field treated to ≥ 4,500 cGy. The concomitant pilocarpine group received 5 mg pilocarpine q.i.d. beginning on day one of radiotherapy and continuing for 3 months after completion of radiation. The control group had their baseline xerostomia measured prior to receiving pilocarpine. They subsequently took 5 mg pilocarpine t.i.d. for one month at which time they underwent a second xerostomia assessment. Xerostomia scores for each group were averaged and compared using the Student's t-test. Results: Seventeen patients who received pilocarpine during head and neck irradiation were compared to 12 post-radiotherapy patients who had not yet taken pilocarpine and the same patients after taking pilocarpine for one month. The mean intervals between completion of radiation and evaluation of xerostomia were 16 months for the control group and 17 months for the pilocarpine treated groups. The primary tumor sites treated as well as the total tumor doses were equivalent between the groups. Only one of the pilocarpine treated patients was still taking pilocarpine at the time of evaluation. Results are shown. For each component of xerostomia measured as well as the composite of all components, the group that had received pilocarpine during radiation had significantly less xerostomia than the no pilocarpine group (p<0.01 for each). Post

  5. Current-horn suppression for reduced coherent-synchrotron-radiation-induced emittance growth in strong bunch compression

    Directory of Open Access Journals (Sweden)

    T. K. Charles

    2017-03-01

    Full Text Available Control of coherent synchrotron radiation (CSR-induced emittance growth is essential in linear accelerators designed to deliver very high brightness electron beams. Extreme current values at the head and tail of the electron bunch, resulting from strong bunch compression, are responsible for large CSR production leading to significant transverse projected emittance growth. The Linac Coherent Light Source (LCLS truncates the head and tail current spikes which greatly improves free electron laser (FEL performance. Here we consider the underlying dynamics that lead to formation of current spikes (also referred to as current horns, which has been identified as caustics forming in electron trajectories. We present a method to analytically determine conditions required to avoid the caustic formation and therefore prevent the current spikes from forming. These required conditions can be easily met, without increasing the transverse slice emittance, through inclusion of an octupole magnet in the middle of a bunch compressor.

  6. A study on reducing radiation dose in dental radiography for children, 1

    International Nuclear Information System (INIS)

    Shikone, Mitsuru; Tsuchida, Atsushi; Tateno, Hidemi; Uchimura, Noboru; Higaki, Morio; Kanno, Masanori; Higashi, Tomomitsu

    1986-01-01

    X-ray examination is one of the effective diagnoses in dentistry. And it is difficult to conduct a precise dental examination without X-ray films, especially in pedodontics. However, radiography may be attended with many radiation injury, and we must perform the complete protection of patients when taking X-ray radiography for children, because their tissues are much more sensitive to radiation than those of adult. Children have some radiosensitive immature organs such as the thyroid gland, eyes (crystalline lens), gonad etc., accordingly, it is very important to protect them from exposure of X-rey. It has been suggested that the thyroid gland is the most sensitive to radiation among many organs. We, therefore, establish a protector for children's thyroid gland as soon as possible. In this study, the auther had designed X-ray protecting rubber sheet which had various lead contents, for finding an optimum condition of the protector. Additionally, the sheltering effects were compared among ready-made protectors. 1. It was satisfactory for complete sheltering of direct beam that the rubber sheet contained 0.375 mmPb, 0.5 mmPb, and 0.75 mmPb, at the tubevoltage of 65 kVp, 70 kVp and 80 kVp, respectively. 2. The radiolucency ratio of Hagoromo Apron containing 0.25 mmPb was 0 % at 65 kVp, and that of X-ray Shield containing 0.50 mmPb was 0 % at 65, 70 kVp and 80 kVp too. 3. Among the ready-made aprons, there was one which had less lead content than the indicated value. (author)

  7. Ambient UV-B radiation reduces PSII performance and net photosynthesis in high Arctic Salix arctica

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Mikkelsen, Teis Nørgaard; Ro-Poulsen, H.

    2011-01-01

    , nitrogen and UV-B absorbing compounds. Compared to a 60% reduced UV-B irradiance, the ambient solar UV-B reduced net photosynthesis in Salix arctica leaves fixed in the 45° position which exposed leaves to maximum natural irradiance. Also a reduced Calvin Cycle capacity was found, i.e. the maximum rate...... across position in the vegetation. These findings add to the evidence that the ambient solar UV-B currently is a significant stress factor for plants in high Arctic Greenland....

  8. Development of radiation immunology

    International Nuclear Information System (INIS)

    Xie Yi; Dang Bingrong; Bing Tao; Zhang Hong; Li Wenjian; Liu Bing

    2005-01-01

    Radiation immunology as a new subject has made a great progress in recent years, especially in the radiation hormesis. At the same time, the research of radiobiological effect on heavy ions has played an important role in the cancer therapy, especially on the radiation immunology of heavy ions in the outer space. In this review, the authors summarized the status and development of radiation-immunology, and try to find out some better ways which can increase efficient killing on tumours, but reduce the damages on normal tissues. (authors)

  9. Vibroacoustics of the piano soundboard: Reduced models, mobility synthesis, and acoustical radiation regime

    Science.gov (United States)

    Boutillon, Xavier; Ege, Kerem

    2013-09-01

    In string musical instruments, the sound is radiated by the soundboard, subject to the strings excitation. This vibration of this rather complex structure is described here with models which need only a small number of parameters. Predictions of the models are compared with the results of experiments that have been presented in Ege et al. [Vibroacoustics of the piano soundboard: (non)linearity and modal properties in the low- and mid-frequency ranges, Journal of Sound and Vibration 332 (5) (2013) 1288-1305]. The apparent modal density of the soundboard of an upright piano in playing condition, as seen from various points of the structure, exhibits two well-separated regimes, below and above a frequency flim that is determined by the wood characteristics and by the distance between ribs. Above flim, most modes appear to be localised, presumably due to the irregularity of the spacing and height of the ribs. The low-frequency regime is predicted by a model which consists of coupled sub-structures: the two ribbed areas split by the main bridge and, in most cases, one or two so-called cut-off corners. In order to assess the dynamical properties of each of the subplates (considered here as homogeneous plates), we propose a derivation of the (low-frequency) modal density of an orthotropic homogeneous plate which accounts for the boundary conditions on an arbitrary geometry. Above flim, the soundboard, as seen from a given excitation point, is modelled as a set of three structural wave-guides, namely the three inter-rib spacings surrounding the excitation point. Based on these low- and high-frequency models, computations of the point-mobility and of the apparent modal densities seen at several excitation points match published measurements. The dispersion curve of the wave-guide model displays an acoustical radiation scheme which differs significantly from that of a thin homogeneous plate. It appears that piano dimensioning is such that the subsonic regime of acoustical

  10. Cost-effectiveness considerations in reducing occupational radiation exposure in nuclear power plants

    International Nuclear Information System (INIS)

    Lochard, J.; Maccia, C.; Pages, P.

    1983-01-01

    This article outlines a method of applying the as-low-as-reasonably-achievable principle to occupational radiation exposures in nuclear power stations. A set of protective actions already taken at French pressurized-water reactors now in operation were selected, and their cost and effectiveness were assessed, allowing for the possible interdependence of protection and energy-production objectives. The usefulness of such quantitative evaluation is discussed with regard to the problem of using monetary values of the man-sievert in optimization procedures

  11. Evaluation of alternative planting strategies to reduce wheat stem sawfly (Hymenoptera: Cephidae) damage to spring wheat in the northern Great Plains.

    Science.gov (United States)

    Beres, B L; Cárcamo, H A; Bremer, E

    2009-12-01

    Wheat, Triticum aestivum L., producers are often reluctant to use solid-stemmed wheat cultivars resistant to wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), due to concerns regarding yield, efficacy or market opportunities. We evaluated the impact of several planting strategies on wheat yield and quality and wheat stem sawfly infestation at two locations over a three-year period. Experimental units consisted of large plots (50 by 200 m) located on commercial farms adjacent to wheat stem sawfly-infested fields. Compared with a monoculture of a hollow-stemmed cultivar ('AC Barrie'), planting a monoculture of a solid-stemmed cultivar ('AC Eatonia') increased yield by an average of 16% (0.4 mg ha(-1)) and increased the grade of wheat by one unit at the two most heavily infested site-years. Planting a 1:1 blend of AC Eatonia and AC Barrie increased yield by an average of 11%, whereas planting 20- or 40-m plot margins to AC Eatonia increased yield by an average of 8%. High wheat stem sawfly pressure limited the effectiveness of using resistant cultivars in field margins because plants were often infested beyond the plot margin, with uniform infestation down the length of the plots at the two most heavily infested site-years. The effectiveness of AC Eatonia to reduce wheat stem sawfly survivorship was modest in this study, probably due to weather-related factors influencing pith expression and to the high abundance of wheat stem sawfly. Greater benefits from planting field margins to resistant cultivars or planting a blend of resistant and susceptible cultivars might be achievable under lower wheat stem sawfly pressure.

  12. New scanning technique using Adaptive Statistical lterative Reconstruction (ASIR) significantly reduced the radiation dose of cardiac CT

    International Nuclear Information System (INIS)

    Tumur, Odgerel; Soon, Kean; Brown, Fraser; Mykytowycz, Marcus

    2013-01-01

    The aims of our study were to evaluate the effect of application of Adaptive Statistical Iterative Reconstruction (ASIR) algorithm on the radiation dose of coronary computed tomography angiography (CCTA) and its effects on image quality of CCTA and to evaluate the effects of various patient and CT scanning factors on the radiation dose of CCTA. This was a retrospective study that included 347 consecutive patients who underwent CCTA at a tertiary university teaching hospital between 1 July 2009 and 20 September 2011. Analysis was performed comparing patient demographics, scan characteristics, radiation dose and image quality in two groups of patients in whom conventional Filtered Back Projection (FBP) or ASIR was used for image reconstruction. There were 238 patients in the FBP group and 109 patients in the ASIR group. There was no difference between the groups in the use of prospective gating, scan length or tube voltage. In ASIR group, significantly lower tube current was used compared with FBP group, 550mA (450–600) vs. 650mA (500–711.25) (median (interquartile range)), respectively, P<0.001. There was 27% effective radiation dose reduction in the ASIR group compared with FBP group, 4.29mSv (2.84–6.02) vs. 5.84mSv (3.88–8.39) (median (interquartile range)), respectively, P<0.001. Although ASIR was associated with increased image noise compared with FBP (39.93±10.22 vs. 37.63±18.79 (mean ±standard deviation), respectively, P<001), it did not affect the signal intensity, signal-to-noise ratio, contrast-to-noise ratio or the diagnostic quality of CCTA. Application of ASIR reduces the radiation dose of CCTA without affecting the image quality.

  13. New scanning technique using Adaptive Statistical Iterative Reconstruction (ASIR) significantly reduced the radiation dose of cardiac CT.

    Science.gov (United States)

    Tumur, Odgerel; Soon, Kean; Brown, Fraser; Mykytowycz, Marcus

    2013-06-01

    The aims of our study were to evaluate the effect of application of Adaptive Statistical Iterative Reconstruction (ASIR) algorithm on the radiation dose of coronary computed tomography angiography (CCTA) and its effects on image quality of CCTA and to evaluate the effects of various patient and CT scanning factors on the radiation dose of CCTA. This was a retrospective study that included 347 consecutive patients who underwent CCTA at a tertiary university teaching hospital between 1 July 2009 and 20 September 2011. Analysis was performed comparing patient demographics, scan characteristics, radiation dose and image quality in two groups of patients in whom conventional Filtered Back Projection (FBP) or ASIR was used for image reconstruction. There were 238 patients in the FBP group and 109 patients in the ASIR group. There was no difference between the groups in the use of prospective gating, scan length or tube voltage. In ASIR group, significantly lower tube current was used compared with FBP group, 550 mA (450-600) vs. 650 mA (500-711.25) (median (interquartile range)), respectively, P ASIR group compared with FBP group, 4.29 mSv (2.84-6.02) vs. 5.84 mSv (3.88-8.39) (median (interquartile range)), respectively, P ASIR was associated with increased image noise compared with FBP (39.93 ± 10.22 vs. 37.63 ± 18.79 (mean ± standard deviation), respectively, P ASIR reduces the radiation dose of CCTA without affecting the image quality. © 2013 The Authors. Journal of Medical Imaging and Radiation Oncology © 2013 The Royal Australian and New Zealand College of Radiologists.

  14. Radiation brain dose to vascular surgeons during fluoroscopically guided interventions is not effectively reduced by wearing lead equivalent surgical caps.

    Science.gov (United States)

    Kirkwood, Melissa L; Arbique, Gary M; Guild, Jeffrey B; Zeng, Katie; Xi, Yin; Rectenwald, John; Anderson, Jon A; Timaran, Carlos

    2018-03-12

    Radiation to the interventionalist's brain during fluoroscopically guided interventions (FGIs) may increase the incidence of cerebral neoplasms. Lead equivalent surgical caps claim to reduce radiation brain doses by 50% to 95%. We sought to determine the efficacy of the RADPAD (Worldwide Innovations & Technologies, Lenexa, Kan) No Brainer surgical cap (0.06 mm lead equivalent at 90 kVp) in reducing radiation dose to the surgeon's and trainee's head during FGIs and to a phantom to determine relative brain dose reductions. Optically stimulated, luminescent nanoDot detectors (Landauer, Glenwood, Ill) inside and outside of the cap at the left temporal position were used to measure cap attenuation during FGIs. To check relative brain doses, nanoDot detectors were placed in 15 positions within an anthropomorphic head phantom (ATOM model 701; CIRS, Norfolk, Va). The phantom was positioned to represent a primary operator performing femoral access. Fluorography was performed on a plastic scatter phantom at 80 kVp for an exposure of 5 Gy reference air kerma with or without the hat. For each brain location, the percentage dose reduction with the hat was calculated. Means and standard errors were calculated using a pooled linear mixed model with repeated measurements. Anatomically similar locations were combined into five groups: upper brain, upper skull, midbrain, eyes, and left temporal position. This was a prospective, single-center study that included 29 endovascular aortic aneurysm procedures. The average procedure reference air kerma was 2.6 Gy. The hat attenuation at the temporal position for the attending physician and fellow was 60% ± 20% and 33% ± 36%, respectively. The equivalent phantom measurements demonstrated an attenuation of 71% ± 2.0% (P < .0001). In the interior phantom locations, attenuation was statistically significant for the skull (6% ± 1.4%) and upper brain (7.2% ± 1.0%; P < .0001) but not for the middle brain (1.4% ± 1.0%; P = .15

  15. Use of a molecular diagnostic test in AFB smear positive tuberculosis suspects greatly reduces time to detection of multidrug resistant tuberculosis.

    Directory of Open Access Journals (Sweden)

    Nestani Tukvadze

    Full Text Available The WHO has recommended the implementation of rapid diagnostic tests to detect and help combat M/XDR tuberculosis (TB. There are limited data on the performance and impact of these tests in field settings.The performance of the commercially available Genotype MTBDRplus molecular assay was compared to conventional methods including AFB smear, culture and drug susceptibility testing (DST using both an absolute concentration method on Löwenstein-Jensen media and broth-based method using the MGIT 960 system. Sputum specimens were obtained from TB suspects in the country of Georgia who received care through the National TB Program.Among 500 AFB smear-positive sputum specimens, 458 (91.6% had both a positive sputum culture for Mycobacterium tuberculosis and a valid MTBDRplus assay result. The MTBDRplus assay detected isoniazid (INH resistance directly from the sputum specimen in 159 (89.8% of 177 specimens and MDR-TB in 109 (95.6% of 114 specimens compared to conventional methods. There was high agreement between the MTBDRplus assay and conventional DST results in detecting MDR-TB (kappa = 0.95, p<0.01. The most prevalent INH resistance mutation was S315T (78% in the katG codon and the most common rifampicin resistance mutation was S531L (68% in the rpoB codon. Among 13 specimens from TB suspects with negative sputum cultures, 7 had a positive MTBDRplus assay (3 with MDR-TB. The time to detection of MDR-TB was significantly less using the MTBDRplus assay (4.2 days compared to the use of standard phenotypic tests (67.3 days with solid media and 21.6 days with broth-based media.Compared to conventional methods, the MTBDRplus assay had high accuracy and significantly reduced time to detection of MDR-TB in an area with high MDR-TB prevalence. The use of rapid molecular diagnostic tests for TB and drug resistance should increase the proportion of patients promptly placed on appropriate therapy.

  16. A study on reducing radiation dose in dental radiography for children, 2

    International Nuclear Information System (INIS)

    Shikone, Mitsuru; Tsuchida, Atsushi; Tateno, Hidemi; Uchimura, Noboru; Higaki, Morio; Kanno, Masanori; Higashi, Tomomitsu

    1987-01-01

    Although it is well understood that diagnostic dental radiographic examination is an indispensible procedure of the dental examination, it always carries the danger of radiation harm especially to the pedodontic patients who are more radiosensitive than the adult group. At the time of exposure, in specific, certain undeveloped tissues such as the thyroid (reverting postmitotic cells), the optic lens, and the reproductive cells (gonads) must be shielded from any unnecessary radiation. In this study, using the pedodontic intraoral radiographic examination method, four various cervical shields of four separate manufacturers were investigated. With the aid of the Thermo Luminescent Dosimeter (TLD), the specific exposure doses to the thyroid gland region were analyzed. At the same time, individual cervical shield's adaptation to the neck was examined. The results were as follows: (1) Even with the use of the cervical shield, maximum dose of 98.64 ± 11.13 mR (lower molar periapical radiography method), and minimum of 34.27 ± 6.69 mR (lower anterior periapical radiography method) were obtained at the thyroid gland region. (2) It was discovered that poor adaptation of the cervical shield to the neck and also poor adaptation of the long cones (position indicating devices, PID) occured upon patient opening his/her mouth. (author)

  17. Fluoroscopy without the grid: a method of reducing the radiation dose

    International Nuclear Information System (INIS)

    Drury, P.; Robinson, A.

    1980-01-01

    The anti-scatter grid has been removed from the fluoroscopic set during the course of over 80 contrast examinations performed routinely during the ordinary workload of a busy paediatric radiology department. This manoeuvre approximatley halves the radiation dose to the patient during both fluoroscopy and radiography. Experience suggests that the degree of loss of contrast consequent on the abandonment of the grid is diagnostically acceptable during many examinations performed on children (of all ages), when balanced against the lower radiation dose received. In addition, an assessment has been made of the contrast improvement factor of the grids in two fluoroscopic sets in common use, using tissue-equivalent phantoms of various thicknesses. Although the contrast was significantly improved by the use of the grid, to a degree dependent on various factors, the relevance of this improvement in clinical radiology depends on exactly what information is being sought. It is recommended that radiologists should use the grid with discretion when performing fluoroscopic examinations on children and that the apparatus for such examinations should have the capability for easy removal and reintroduction of the grid. (author)

  18. Method and apparatus for reducing radiation exposure through the use of infrared data transmission

    Science.gov (United States)

    Austin, Frank S.; Hance, Albert B.

    1989-01-01

    A method and apparatus is described for transmitting information, for exae, dosimetry data from a hazardous environment such as a radioactive area to a remote relatively safe location. A radiation detector senses the radiation and generates an electrical signal which is fed as a binary coded decimal signal to an infrared transmitter having a microprocessor. The microprocessor formats the detected information into digits of data and modulates a 40 kHz oscillator, the output of which is fed to and intensity modulates one or more infrared emitting diodes. The infrared signal from the diodes is transmitted to a portable hand-held infrared receiver remote from the hazardous environment. The receiver includes an infrared sensitive diode which decodes the data and generates an electrical signal which is coupled to a microcomputer. The microcomputer synchronizes itself to the transmitter, reads the digits of data as they are received, sums the digits and compares the sum with a checksum signal generated and transmitted from the transmitter. If a match of the checksum signals exists, the received data is displayed, otherwise it is described and the receiver conditions itself for the next transmission of data.

  19. Ascorbic acid reduced mutagenicity at the HPRT locus in CHO cells against thermal neutron radiation

    International Nuclear Information System (INIS)

    Kinashi, Yuko; Sakurai, Yoshinori; Masunaga, Shinichiro; Suzuki, Minoru; Nagata, Kenji; Ono, Koji

    2004-01-01

    We investigated the biological effects of the long-lived radicals induced following neutron irradiation. It has been reported that radiation-induced long-lived radicals were scavenged by post-irradiation treatment of ascorbic acid (Koyama, 1998). We studied the effects of ascorbic acid acting as a long-lived radical scavenger on cell killing and mutagenicity in Chinese hamster ovary cells against thermal neutrons produced at the Kyoto University Research reactor. Ascorbic acid was added to cells 30 min after neutron irradiation and removed 150 min after irradiation. The biological end point of cell survival was measured by colony formation assay. The mutagenicity was measured by the mutant frequency in the HPRT locus. The post-irradiation treatment of ascorbic acid did not alter the cell killing effect of neutron radiation. However, the mutagenicity was decreased, especially when the cells were irradiated with boron. Our results suggested that ascorbic acid scavenged long-lived radicals effectively and caused apparent protective effects against mutagenicity of boron neutron capture therapy

  20. Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children.

    Science.gov (United States)

    Kim, Hyun Gi; Lee, Ho-Joon; Lee, Seung-Koo; Kim, Hyun Ji; Kim, Myung-Joon

    2017-09-01

    To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols. A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V. Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P ASIR-V. Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality. • It is possible to reduce radiation dose and improve image quality with ASIR-V. • We improved noise and CNR and decreased radiation dose. • Sharpness improved with ASIR-V. • Total radiation dose was decreased by 12.8% to 34.0%.

  1. Reduced Toxicity With Intensity Modulated Radiation Therapy (IMRT) for Desmoplastic Small Round Cell Tumor (DSRCT): An Update on the Whole Abdominopelvic Radiation Therapy (WAP-RT) Experience

    Energy Technology Data Exchange (ETDEWEB)

    Desai, Neil B. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Stein, Nicholas F. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); LaQuaglia, Michael P. [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Alektiar, Kaled M. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Kushner, Brian H.; Modak, Shakeel; Magnan, Heather M. [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Goodman, Karyn [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2013-01-01

    Purpose: Desmoplastic small round cell tumor (DSRCT) is a rare malignancy typically involving the peritoneum in young men. Whole abdominopelvic radiation therapy (WAP-RT) using conventional 2-dimensional (2D) radiation therapy (RT) is used to address local recurrence but has been limited by toxicity. Our objectives were to assess the benefit of intensity modulated radiation therapy (IMRT) on toxicity and to update the largest series on radiation for DSRCT. Methods and Materials: The records of 31 patients with DSRCT treated with WAP-RT (22 with 2D-RT and 9 with IMRT) between 1992 and 2011 were retrospectively reviewed. All received multi-agent chemotherapy and maximal surgical debulking followed by 30 Gy of WAP-RT. A further focal boost of 12 to 24 Gy was used in 12 cases. Boost RT and autologous stem cell transplantation were nearly exclusive to patients treated with 2D-RT. Toxicities were assessed with the Common Terminology Criteria for Adverse Events. Dosimetric analysis compared IMRT and simulated 2D-RT dose distributions. Results: Of 31 patients, 30 completed WAP-RT, with a median follow-up after RT of 19 months. Acute toxicity was reduced with IMRT versus 2D-RT: P=.04 for gastrointestinal toxicity of grade 2 or higher (33% vs 77%); P=.02 for grade 4 hematologic toxicity (33% vs 86%); P=.01 for rates of granulocyte colony-stimulating factor; and P=.04 for rates of platelet transfusion. Post treatment red blood cell and platelet transfusion rates were also reduced (P=.01). IMRT improved target homogeneity ([D05-D95]/D05 of 21% vs 46%) and resulted in a 21% mean bone dose reduction. Small bowel obstruction was the most common late toxicity (23% overall). Updated 3-year overall survival and progression-free survival rates were 50% and 24%, respectively. Overall survival was associated with distant metastasis at diagnosis on multivariate analysis. Most failures remained intraperitoneal (88%). Conclusions: IMRT for consolidative WAP-RT in DSRCT improves

  2. Possibilities of reducing radiation doses in spinograms of adolescents by means of most intensifying screens and compensating screens

    Energy Technology Data Exchange (ETDEWEB)

    Pollaehne, W; Brandt, G A [Staedtisches Klinikum Berlin-Buch (German Democratic Republic)

    1980-01-01

    Most intensifying screens based on CaWO/sub 4/ and LaOBr/sub 2/ or combinations of them were used in radiography of both the thoracic and the lumbar parts of the spines of adolescents. The results obtained were compared with those achieved by means of screens usually used for spinograms. Radiation exposure was reduced, on an average by 30-40%, when most intensifying screens were used, the image quality being the same. The introduction of high-speed superscreens is pressingly recommended.

  3. Mangiferin Reduces Oxidative Stress-mediated Renal Injury in γ-radiated Mice

    International Nuclear Information System (INIS)

    El-Kabany, H.; Lotfi, S.A.

    2012-01-01

    Whole body exposure to ionizing radiation induces the formation of reactive oxygen species in different tissues provoking oxidative damage and tissue injury. Mangiferin (MGN), 1,3,6,7-tetra hydroxyxanthone-C 2 -β-D-glucoside, a naturally occurring polyphenol, present in Mangifera indica (M. indica) in large amounts in the leaves and edible mango fruits has been reported to possess antioxidant properties. The purpose of this study was to evaluate the role of MGN on radiation-induced oxidative stress and histological changes in the kidney of mice. MGN (20 mg/ kg body weight) was administrated to male albino mice via gavages during 15 successive days before whole body exposures to gamma rays (4 Gy). The animals were sacrificed 48 hours post irradiation. Biochemical analysis in the kidney of irradiated mice revealed an imbalance between oxidant and antioxidant species. A significant increase was recorded in the level of lipid peroxidation products; thiobarbituric acid reactive substances (TBARs) and lipid hydroperoxides (HDPx), in addition to a significant increase in the level of protein carbonyl content (PC) , marker of protein oxidation. The increase of oxidative markers was accompanied by a significant decrease in the contents of total sulphydryl (SH) group ,glutathione (GSH) content, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) activity. Moreover, irradiation induced a significant decrease in the activity of glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD). Histological observations in the kidney of irradiated mice revealed tubular necrosis, degeneration, dilatation, desquamation, thickening of basement membrane and luminal cast formation. MGN pre-treatment has significantly improved the oxidant /antioxidant status, which was associated with significant regeneration of the kidney tissue. Based on these results, it is concluded that the natural dietary antioxidant M GN m ight

  4. Adaptive statistical iterative reconstruction reduces patient radiation dose in neuroradiology CT studies

    Energy Technology Data Exchange (ETDEWEB)

    Komlosi, Peter; Zhang, Yanrong; Leiva-Salinas, Carlos; Ornan, David; Grady, Deborah [University of Virginia, Department of Radiology and Medical Imaging, Division of Neuroradiology, PO Box 800170, Charlottesville, VA (United States); Patrie, James T.; Xin, Wenjun [University of Virginia, Department of Public Health Sciences, Charlottesville, VA (United States); Wintermark, Max [University of Virginia, Department of Radiology and Medical Imaging, Division of Neuroradiology, PO Box 800170, Charlottesville, VA (United States); Centre Hospitalier Universitaire Vaudois, Department of Radiology, Lausanne (Switzerland)

    2014-03-15

    Adaptive statistical iterative reconstruction (ASIR) can decrease image noise, thereby generating CT images of comparable diagnostic quality with less radiation. The purpose of this study is to quantify the effect of systematic use of ASIR versus filtered back projection (FBP) for neuroradiology CT protocols on patients' radiation dose and image quality. We evaluated the effect of ASIR on six types of neuroradiologic CT studies: adult and pediatric unenhanced head CT, adult cervical spine CT, adult cervical and intracranial CT angiography, adult soft tissue neck CT with contrast, and adult lumbar spine CT. For each type of CT study, two groups of 100 consecutive studies were retrospectively reviewed: 100 studies performed with FBP and 100 studies performed with ASIR/FBP blending factor of 40 %/60 % with appropriate noise indices. The weighted volume CT dose index (CTDI{sub vol}), dose-length product (DLP) and noise were recorded. Each study was also reviewed for image quality by two reviewers. Continuous and categorical variables were compared by t test and free permutation test, respectively. For adult unenhanced brain CT, CT cervical myelography, cervical and intracranial CT angiography and lumbar spine CT both CTDI{sub vol} and DLP were lowered by up to 10.9 % (p < 0.001), 17.9 % (p = 0.005), 20.9 % (p < 0.001), and 21.7 % (p = 0.001), respectively, by using ASIR compared with FBP alone. Image quality and noise were similar for both FBP and ASIR. We recommend routine use of iterative reconstruction for neuroradiology CT examinations because this approach affords a significant dose reduction while preserving image quality. (orig.)

  5. Adaptive statistical iterative reconstruction reduces patient radiation dose in neuroradiology CT studies

    International Nuclear Information System (INIS)

    Komlosi, Peter; Zhang, Yanrong; Leiva-Salinas, Carlos; Ornan, David; Grady, Deborah; Patrie, James T.; Xin, Wenjun; Wintermark, Max

    2014-01-01

    Adaptive statistical iterative reconstruction (ASIR) can decrease image noise, thereby generating CT images of comparable diagnostic quality with less radiation. The purpose of this study is to quantify the effect of systematic use of ASIR versus filtered back projection (FBP) for neuroradiology CT protocols on patients' radiation dose and image quality. We evaluated the effect of ASIR on six types of neuroradiologic CT studies: adult and pediatric unenhanced head CT, adult cervical spine CT, adult cervical and intracranial CT angiography, adult soft tissue neck CT with contrast, and adult lumbar spine CT. For each type of CT study, two groups of 100 consecutive studies were retrospectively reviewed: 100 studies performed with FBP and 100 studies performed with ASIR/FBP blending factor of 40 %/60 % with appropriate noise indices. The weighted volume CT dose index (CTDI vol ), dose-length product (DLP) and noise were recorded. Each study was also reviewed for image quality by two reviewers. Continuous and categorical variables were compared by t test and free permutation test, respectively. For adult unenhanced brain CT, CT cervical myelography, cervical and intracranial CT angiography and lumbar spine CT both CTDI vol and DLP were lowered by up to 10.9 % (p < 0.001), 17.9 % (p = 0.005), 20.9 % (p < 0.001), and 21.7 % (p = 0.001), respectively, by using ASIR compared with FBP alone. Image quality and noise were similar for both FBP and ASIR. We recommend routine use of iterative reconstruction for neuroradiology CT examinations because this approach affords a significant dose reduction while preserving image quality. (orig.)

  6. Reducing radiation dose to the female breast during conventional and dedicated breast computed tomography

    Science.gov (United States)

    Rupcich, Franco John

    The purpose of this study was to quantify the effectiveness of techniques intended to reduce dose to the breast during CT coronary angiography (CTCA) scans with respect to task-based image quality, and to evaluate the effectiveness of optimal energy weighting in improving contrast-to-noise ratio (CNR), and thus the potential for reducing breast dose, during energy-resolved dedicated breast CT. A database quantifying organ dose for several radiosensitive organs irradiated during CTCA, including the breast, was generated using Monte Carlo simulations. This database facilitates estimation of organ-specific dose deposited during CTCA protocols using arbitrary x-ray spectra or tube-current modulation schemes without the need to run Monte Carlo simulations. The database was used to estimate breast dose for simulated CT images acquired for a reference protocol and five protocols intended to reduce breast dose. For each protocol, the performance of two tasks (detection of signals with unknown locations) was compared over a range of breast dose levels using a task-based, signal-detectability metric: the estimator of the area under the exponential free-response relative operating characteristic curve, AFE. For large-diameter/medium-contrast signals, when maintaining equivalent AFE, the 80 kV partial, 80 kV, 120 kV partial, and 120 kV tube-current modulated protocols reduced breast dose by 85%, 81%, 18%, and 6%, respectively, while the shielded protocol increased breast dose by 68%. Results for the small-diameter/high-contrast signal followed similar trends, but with smaller magnitude of the percent changes in dose. The 80 kV protocols demonstrated the greatest reduction to breast dose, however, the subsequent increase in noise may be clinically unacceptable. Tube output for these protocols can be adjusted to achieve more desirable noise levels with lesser dose reduction. The improvement in CNR of optimally projection-based and image-based weighted images relative to photon

  7. Long-term efficacy of a mini-course in radiation-reducing techniques in invasive cardiology

    Energy Technology Data Exchange (ETDEWEB)

    Kuon, E. [Klinik Fraenkische Schweiz, Ebermannstadt (Germany). Abt. fuer Kardiologie; Empen, K.; Hummel, A.; Doerr, M.; Reffelmann, T.; Felix, S.B. [Ernst-Moritz-Arndt-Universitaet, Greifswald (Germany). Abt. fuer Innere Medizin B; Weitmann, K.; Hoffmann, W. [Ernst-Moritz-Arndt-Universitaet, Greifswald (Germany). Inst. fuer Versorgungsmedizin; Staudt, A. [Helios Kliniken, Schwerin (Germany). Abt. fuer Kardiologie und Angiologie

    2013-08-15

    Purpose: To validate the long-term efficacy of a 90-min. educational mini-course in less-irradiating cardiac interventional techniques. Materials and Methods: Before, two months after, and two years after the mini-course (periods I, II, and III), we analyzed the following radiation dose parameters for ten coronary angiographies (CA), performed by each of 7 cardiologists: total dose-area product (DAP), radiographic and fluoroscopic DAP fractions, number of radiographic frames and runs, and fluoroscopy time. Results: The median patient DAP for periods I, II and III was 31.4, 15.8 and 8.5 Gy x cm{sup 2}, respectively. The long-term effect was related to shorter median fluoroscopy times (180, 172, and 120 s), shorter (57, 52, and 45) and fewer (12, 12, and 10) radiographic runs, consistent collimation and restriction to an adequate image quality. Both radiographic DAP/frame (28.7, 17.0, and 18.4 mGy x cm{sup 2}) and fluoroscopic DAP/second (45.7, 24.2, and 10.0 mGy x cm{sup 2}) decreased significantly. The multivariate linear regression analysis confirmed the increasing efficacy of the mini-course itself (-44.6 and -60.7 %), and revealed a decreasing influence of the interventionalist's experience (-8.6 % and -4.9 % per 1,000 CAs, lifelong performed until the mini-course). The number of CAs performed after the mini-course did not influence the long-term DAP results. Conclusion: The presented educational mini-course allows a significant, long-lasting, and apparently ongoing reduction of patient radiation exposure due to CA. A self-surveillant documentation of relevant radiation parameters is well suited to monitor and improve each operator's individual long-term radiation-reducing efforts. (orig.)

  8. Cancer-associated fibroblasts from human NSCLC survive ablative doses of radiation but their invasive capacity is reduced

    Directory of Open Access Journals (Sweden)

    Hellevik Turid

    2012-04-01

    Full Text Available Abstract Background Cancer-Associated Fibroblasts (CAFs are significant components of solid malignancies and play central roles in cancer sustainability, invasion and metastasis. In this study we have investigated the invasive capacity and matrix remodelling properties of human lung CAFs after exposure to ablative doses of ionizing radiation (AIR, equivalent to single fractions delivered by stereotactic ablative radiotherapy (SART for medically inoperable stage-I/II non-small-cell lung cancers. Methods CAFs were isolated from lung tumour specimens from 16 donors. Initially, intrinsic radiosensitivity was evaluated by checking viability and extent of DNA-damage response (DDR at different radiation doses. The migrative and invasive capacities of CAFs were thereafter determined after a sub-lethal single radiation dose of 18 Gy. To ascertain the mechanisms behind the altered invasive capacity of cells, expression of matrix metalloproteinases (MMPs and their endogenous inhibitors (TIMPs were measured in the conditioned media several days post-irradiation, along with expression of cell surface integrins and dynamics of focal contacts by vinculin-staining. Results Exposing CAFs to 1 × 18 Gy resulted in a potent induction of multiple nuclear DDR foci (> 9/cell with little resolution after 120 h, induced premature cellular senescence and inhibition of the proliferative, migrative and invasive capacity. AIR promoted MMP-3 and inhibited MMP-1 appearance to some extent, but did not affect expression of other major MMPs. Furthermore, surface expression of integrins α2, β1 and α5 was consistently enhanced, and a dramatic augmentation and redistribution of focal contacts was observed. Conclusions Our data indicate that ablative doses of radiation exert advantageous inhibitory effects on the proliferative, migratory and invasive capacity of lung CAFs. The reduced motility of irradiated CAFs might be a consequence of stabilized focal contacts via integrins.

  9. Long-term efficacy of a mini-course in radiation-reducing techniques in invasive cardiology

    International Nuclear Information System (INIS)

    Kuon, E.; Empen, K.; Hummel, A.; Doerr, M.; Reffelmann, T.; Felix, S.B.; Weitmann, K.; Hoffmann, W.; Staudt, A.

    2013-01-01

    Purpose: To validate the long-term efficacy of a 90-min. educational mini-course in less-irradiating cardiac interventional techniques. Materials and Methods: Before, two months after, and two years after the mini-course (periods I, II, and III), we analyzed the following radiation dose parameters for ten coronary angiographies (CA), performed by each of 7 cardiologists: total dose-area product (DAP), radiographic and fluoroscopic DAP fractions, number of radiographic frames and runs, and fluoroscopy time. Results: The median patient DAP for periods I, II and III was 31.4, 15.8 and 8.5 Gy x cm 2 , respectively. The long-term effect was related to shorter median fluoroscopy times (180, 172, and 120 s), shorter (57, 52, and 45) and fewer (12, 12, and 10) radiographic runs, consistent collimation and restriction to an adequate image quality. Both radiographic DAP/frame (28.7, 17.0, and 18.4 mGy x cm 2 ) and fluoroscopic DAP/second (45.7, 24.2, and 10.0 mGy x cm 2 ) decreased significantly. The multivariate linear regression analysis confirmed the increasing efficacy of the mini-course itself (-44.6 and -60.7 %), and revealed a decreasing influence of the interventionalist's experience (-8.6 % and -4.9 % per 1,000 CAs, lifelong performed until the mini-course). The number of CAs performed after the mini-course did not influence the long-term DAP results. Conclusion: The presented educational mini-course allows a significant, long-lasting, and apparently ongoing reduction of patient radiation exposure due to CA. A self-surveillant documentation of relevant radiation parameters is well suited to monitor and improve each operator's individual long-term radiation-reducing efforts. (orig.)

  10. A filter for reducing the angular dependence of LiF; Ti, Mg for beta radiation

    International Nuclear Information System (INIS)

    Akabani, G.; Poston, J.W. Sr.

    1990-01-01

    This paper reports on an improvement in the angular dependence of LiF:Ti,Mg (TAD-100) for beta radiation which was achieved by using a special filter design which produced a constant dosimeter response over a range of +70 degrees and -70 degrees. The filter material used was acetate. The filter design was tested with three different beta sources, Sr/Y-90, Tl-204 and Pm-147 with average energies of 0.8, 0.24 and 0.06 MeV, respectively. The average response at 180 degrees of the new filtered dosimeter differed by less than 5% when compared to the response at zero degrees. An average decrease in sensitivity of 53% for Sr-90, 70% for Tl-204 and 67% for Pm-147 was obtained due to filter use. All doses were calculated for a depth dose in tissue of 0.07 mm equivalent to 7 mg/cm 2 as is recommended in ICRP Publication 26. A comparison of the energy dependence for a bare TAD-100 at 0.0 mm and 0.07 mm depth in tissue was obtained

  11. [Effective Techniques to Reduce Radiation Exposure to Medical Staff during Assist of X-ray Computed Tomography Examination].

    Science.gov (United States)

    Miyajima, Ryuichi; Fujibuchi, Toshioh; Miyachi, Yusuke; Tateishi, Satoshi; Uno, Yoshinori; Amakawa, Kazutoshi; Ohura, Hiroki; Orita, Shinichi

    2018-01-01

    Medical staffs like radiological technologists, doctors, and nurses are at an increased risk of exposure to radiation while assisting the patient in a position or monitor contrast medium injection during computed tomography (CT). However, methods to protect medical staff from radiation exposure and protocols for using radiological protection equipment have not been standardized and differ among hospitals. In this study, the distribution of scattered X-rays in a CT room was measured by placing electronic personal dosimeters in locations where medical staff stands beside the CT scanner gantry while assisting the patient and the exposure dose was measured. Moreover, we evaluated non-uniform exposure and revealed effective techniques to reduce the exposure dose to medical staff during CT. The dose of the scattered X-rays was the lowest at the gantry and at the examination table during both head and abdominal CT. The dose was the highest at the trunk of the upper body of the operator corresponding to a height of 130 cm during head CT and at the head corresponding to a height of 150 cm during abdominal CT. The maximum dose to the crystalline lens was approximately 600 μSv during head CT. We found that the use of volumetric CT scanning and X-ray protective goggles, and face direction toward the gantry reduced the exposure dose, particularly to the crystalline lens, for which lower equivalent dose during CT scan has been recently recommended in the International Commission on Radiological Protection Publication 118.

  12. Reducing Radiation Doses in Female Breast and Lung during CT Examinations of Thorax: A new Technique in two Scanners

    Directory of Open Access Journals (Sweden)

    Mehnati P.

    2017-09-01

    Full Text Available Background: Chest CT is a commonly used examination for the diagnosis of lung diseases, but a breast within the scanned field is nearly never the organ of interest. Objective: The purpose of this study is to compare the female breast and lung doses using split and standard protocols in chest CT scanning. Materials and Methods: The sliced chest and breast female phantoms were used. CT exams were performed using a single-slice (SS- and a 16 multi-slice (MS- CT scanner at 100 kVp and 120 kVp. Two different protocols, including standard and split protocols, were selected for scanning. The breast and lung doses were measured using thermo-luminescence dosimeters which were inserted into different layers of the chest and breast phantoms. The differences in breast and lung radiation doses in two protocols were studied in two scanners, analyzed by SPSS software and compared by t-test. Results: Breast dose by split scanning technique reduced 11% and 31% in SS- and MS- CT. Also, the radiation dose of lung tissue in this method decreased 18% and 54% in SS- and MS- CT, respectively. Moreover, there was a significant difference (p< 0.0001 in the breast and lung radiation doses between standard and split scanning protocols. Conclusion: The application of a split scan technique instead of standard protocol has a considerable potential to reduce breast and lung doses in SS- and MS- CT scanners. If split scanning protocol is associated with an optimum kV and MSCT, the maximum dose decline will be provided.

  13. A 25-month database of stratus cloud properties generated from ground-based measurements at the Atmospheric Radiation Measurement Southern Great Plains Site

    International Nuclear Information System (INIS)

    Dong, Xiquan; Minnis, Patrick; Ackerman, Thomas P.; Clothiaux, Eugene E.; Mace, Gerald G.; Long, Charles N.; Liljegren, James C.

    2000-01-01

    A 25-month database of the macrophysical, microphysical, and radiative properties of isolated and overcast low-level stratus clouds has been generated using a newly developed parameterization and surface measurements from the Atmospheric Radiation Measurement central facility in Oklahoma. The database (5-min resolution) includes two parts: measurements and retrievals. The former consist of cloud base and top heights, layer-mean temperature, cloud liquid water path, and solar transmission ratio measured by a ground-based lidar/ceilometer and radar pair, radiosondes, a microwave radiometer, and a standard Eppley precision spectral pyranometer, respectively. The retrievals include the cloud-droplet effective radius and number concentration and broadband shortwave optical depth and cloud and top-of-atmosphere albedos. Stratus without any overlying mid or high-level clouds occurred most frequently during winter and least often during summer. Mean cloud-layer altitudes and geometric thicknesses were higher and greater, respectively, in summer than in winter. Both quantities are positively correlated with the cloud-layer mean temperature. Mean cloud-droplet effective radii range from 8.1 μm in winter to 9.7 μm during summer, while cloud-droplet number concentrations during winter are nearly twice those in summer. Since cloud liquid water paths are almost the same in both seasons, cloud optical depth is higher during the winter, leading to greater cloud albedos and lower cloud transmittances. (c) 2000 American Geophysical Union

  14. A study of a measure for reducing radiation dose in dental radiography for children

    International Nuclear Information System (INIS)

    Tateno, Hidemi

    1982-01-01

    For this investigation the author employed the stabilized TLD and measured the effect of doses on several organs (of children) using water and Mix-D phantom. Based upon this data, the author developed an exposure cone (of children) which was thought to be the best concrete method for reduction of absorbed doses for children who are most frequentry X-rayed and therefore most likely to reduced absorbed doses in a considerable amount. The major findings have been obtained concerning this cone compared with the standard cone as follows. 1. The full mouth 6-film examination showed the largest of the absorbed doses to be on skin, eyes and the thyroid gland. 2. For example, the dose on thyroid gland with a full mouth 6-film examination was 0.734R. 3. The dose on the gonad was less than 0.001R with every technique. 4. Using the developed exposure cone for children we have succeeded in reducing the amount of doses on these organs. In addition the image quality improved due to the reduction of scattered X-rays. 5. Using the developed exposure cone (for children) the risk of thyroid cancer can be reduced a level of 10 -6 to a level of 10 -7 as compared with the standard exposure cone. 6. Supposing that it is over the crystalline lens limits of dose-equivalent in a year at several times with full mouth 6-film examinations can be estimated which with standard cone was about three times, developed cone was about eighty-eight times in a year. (J.P.N.)

  15. A modified technique for craniospinal irradiation in children designed to reduce acute and late radiation toxicity

    International Nuclear Information System (INIS)

    Phillips, Claire; Sexton, Maree

    2004-01-01

    Craniospinal irradiation is an important technique for the treatment of a number of paediatric malignancies. The conventional technique uses photons for all fields and does not exploit the benefits of CT and computer planning systems. The present paper describes a modification of the conventional technique in which both photons and electrons are used for the spinal field (mixed-beam technique). Computed tomography images and a planning computer are used for the selection of field junctions, electron beam energy and dosimetry. The intention of the technique is to reduce radiotherapy toxicity. A discussion of the potential benefits is presented Copyright (2004) Blackwell Publishing Asia Pty Ltd

  16. The use of ionizing radiation to reduce food spoilage by microorganisms

    International Nuclear Information System (INIS)

    Mosquera, Monica; Gomezjurado, Silvia; Munoz, Ricardo

    1990-01-01

    The contamination of Aspergillus flavus is studied in yellow maize, Zea mays, Peanuts, Arachis hipoguea, L.; Casabe, Yuca. Manhot esculenta, D.C. The contents of aflotoxines B 1 , B 2 , G 1 and G 2 is analized in food stuffs of popular consumption. The samples with higher contamination of A. flavus were irradiated with 1-3 KGy, and combined processes with gamma irradiation were assayed with previous and separate treatments with ammonia and hipochlorite. Thus, it was possible to lower the contamination of this fungus from 10 3 u.f.c/g to 10. Separate edible mushrooms of species Boletus edulis, were radurized with gamma irradiation dose of 2 KGy. It was possible to reduce the contamination of 10 7 microorganism/gram, to the value 10 3 - 10 2 microorganism/gram. The microbial contamination of 18 species and aromatic herbs is also studied. The contaminating fungi of these food products as well as of the edible mushrooms, were identified as Penicillum, Geortrichum, Mucor, Galdosporium and yeasts of Canida sp. The optimal irradiation doses of same species and tea herbs, are determined. At the same time de d10 irradiation doses for pure stubs of main microorganisms are determined. To reduce the microbial contamination of many foodstuffs to maximun permisible values it is proposed thesi technology eitherwith only irradiation, or with combined treatments with irradiation

  17. The Great Recession was not so Great

    NARCIS (Netherlands)

    van Ours, J.C.

    2015-01-01

    The Great Recession is characterized by a GDP-decline that was unprecedented in the past decades. This paper discusses the implications of the Great Recession analyzing labor market data from 20 OECD countries. Comparing the Great Recession with the 1980s recession it is concluded that there is a

  18. Photoprotection, photosynthesis and growth of tropical tree seedlings under near-ambient and strongly reduced solar ultraviolet-B radiation.

    Science.gov (United States)

    Krause, G Heinrich; Jahns, Peter; Virgo, Aurelio; García, Milton; Aranda, Jorge; Wellmann, Eckard; Winter, Klaus

    2007-10-01

    Seedlings of two late-successional tropical rainforest tree species, Tetragastris panamensis (Engler) O. Kuntze and Calophyllum longifolium (Willd.), were field grown for 3-4 months at an open site near Panama City (9 degrees N), Panama, under plastic films that either transmitted or excluded most solar UV-B radiation. Experiments were designed to test whether leaves developing under bright sunlight with strongly reduced UV-B are capable of acclimating to near-ambient UV-B conditions. Leaves of T. panamensis that developed under near-ambient UV-B contained higher amounts of UV-absorbing substances than leaves of seedlings grown under reduced UV-B. Photosynthetic pigment composition, content of alpha-tocopherol, CO(2) assimilation, potential photosystem II (PSII) efficiency (evaluated by F(v)/F(m) ratios) and growth of T. panamensis and C. longifolium did not differ between seedlings developed under near-ambient and reduced solar UV-B. When seedlings were transferred from the reduced UV-B treatment to the near-ambient UV-B treatment, a pronounced inhibition of photosynthetic capacity was observed initially in both species. UV-B-mediated inhibition of photosynthetic capacity nearly fully recovered within 1 week of the transfer in C. longifolium, whereas in T. panamensis an about 35% reduced capacity of CO(2) uptake was maintained. A marked increase in UV-absorbing substances was observed in foliage of transferred T. panamensis seedlings. Both species exhibited enhanced mid-day photoinhibition of PSII immediately after being transferred from the reduced UV-B to the near-ambient UV-B treatment. This effect was fully reversible within 1d in T. panamensis and within a few days in C. longifolium. The data show that leaves of these tropical tree seedlings, when developing in full-spectrum sunlight, are effectively protected against high solar UV-B radiation. In contrast, leaves developing under conditions of low UV-B lacked sufficient UV protection. They experienced a

  19. The effectiveness of UV-C radiation for facility-wide environmental disinfection to reduce health care-acquired infections.

    Science.gov (United States)

    Napolitano, Nathanael A; Mahapatra, Tanmay; Tang, Weiming

    2015-12-01

    Health care-acquired infections (HAIs) constitute an increasing threat for patients worldwide. Potential contributors of HAIs include environmental surfaces in health care settings, where ultraviolet-C radiation (UV-C) is commonly used for disinfection. This UV-C intervention-based pilot study was conducted in a hospital setting to identify any change in the incidence of HAIs before and after UV-C intervention, and to determine the effectiveness of UV-C in reducing pathogens. In a hospital in Culver City, CA, during 2012-2013, bactericidal doses of UV-C radiation (254 nm) were delivered through a UV-C-based mobile environmental decontamination unit. The UV-C dosing technology and expertise of the specifically trained personnel were provided together as a dedicated service model by a contracted company. The incidence of HAIs before and after the intervention period were determined and compared. The dedicated service model dramatically reduced HAIs (incidence difference, 1.3/1000 patient-days, a 34.2% reduction). Reductions in the total number and incidence proportions (28.8%) of HAIs were observed after increasing and maintaining the coverage of UV-C treatments. The dedicated service model was found to be effective in decreasing the incidence of HAIs, which could reduce disease morbidity and mortality in hospitalized patients. This model provides a continuously monitored and frequently UV-C-treated patient environment. This approach to UV-C disinfection was associated with a decreased incidence of HAIs. Copyright © 2015 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  20. Does kombucha tea reduce the damage-induced by radiation exposure?

    International Nuclear Information System (INIS)

    Gharib, O.A.

    2007-01-01

    This work has been performed to investigate the protective effect and the antimicrobial activity that occur following oral administration of kombucha tea (kt) ferment in rats with a fractionated dose of 9 Gy. The protective effect of kt ferment was monitored by assessment of serum enzymes activities of creatin phosphokinase (CPK), lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (GGT) and concentrations of urea and creatinine as well as contents of reduced glutathione (GSH) and malonaldehyde (MDA) in heart, liver and kidney tissues. Besides evaluation of the antimicrobial activity was carried out by determination of the lactic acid bacterial (LAB) count as an example of the beneficial bacteria in the rat intestine and the Staphylococcus aureus bacteria (S. aureus) count as an example of the pathogenic bacteria for rats. The results obtained suggest that administration of this ferment tea could ameliorate biochemical and microbial disturbances in irradiated rats

  1. International efforts to reduce occupational radiation exposure at nuclear power plants

    International Nuclear Information System (INIS)

    Khan, T.A.; Baum, J.W.

    1986-01-01

    The efficacy of various national programs on dose reduction is examined with a view to evaluating the most significant factors that help in reducing occupational exposure. Among the most successful of the dose reduction programs at water reactors are those of France, Sweden, and Canada where average annual plant doses are significantly less than the dose at US plants. Important research is also going on in other countries such as the UK, West Germany, Switzerland, and Japan. Some programs are directed towards hardware solutions; others are oriented towards such approaches as better work planning and procedures. The general thrust and some of the specifics of these programs are examined and factors which may be applicable to US conditions are discussed

  2. Reduced hypothalamic blood flow after radiation treatment of nasopharyngeal cancer: SPECT studies in 34 patients

    International Nuclear Information System (INIS)

    Chieng, P.U.; Huang, T.S.; Chang, C.C.; Chong, P.N.; Tien, R.D.; Su, C.T.

    1991-01-01

    To determine the effect of cranial irradiation on hypothalamic blood flow, the authors performed 44 regional cerebral blood flow studies with 99mTc hexamethyl propyleneamine oxime (HMPAO) single-photon emission CT (SPECT) on four normal volunteers and 34 patients with pathologically proved nasopharyngeal cancer. Twenty-three men and 15 women, 30-65 years old, were divided into four study groups: group 1 served as a control and consisted of four normal volunteers and six patients studied prior to cranial irradiation; group 2 patients had cranial irradiation half a year before the SPECT study (n = 12, one from group 1); group 3 patients were irradiated 1 year before the study (n = 13, three from group 1 and two from group 2); and group 4 patients were irradiated at least 5 years before SPECT imaging (n = 9). Six patients were studied twice. Quantification of the 99mTc-HMPAO brain SPECT studies was done separately by three radiologists to obtain the hypothalamus/occipital (H/O) and hypothalamus/parasagittal (H/P) ratios. Endocrinologic studies were performed in all cases and the hypothalamus-thyrotroph-thyroid, hypothalamus-gonadotroph-testis (ovary), hypothalamus-lactotroph, hypothalamus-somatotroph, and hypothalamus-corticotroph-adrenal axes were evaluated separately. They determined that regional hypothalamic blood flow was reduced after cranial irradiation in patients with nasopharyngeal cancer. The H/O ratio of groups 3 and 4 did not differ from that of group 2 (one-half year after cranial irradiation). The H/O ratio was significantly reduced 6 months and 1 year after cranial irradiation; mean ± SD = 0.5801 ± 0.0829 (p less than .025), 0.5725 ± 0.0791 (p less than .01) versus 0.6477 ± 0.0458 before cranial irradiation, respectively

  3. The Great Plains low-level jet (LLJ) during the atmospheric radiation measurement (ARM) intensive observation period (IOP)-4 and simulations of land use pattern effect on the LLJ

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.; Raman, S. [North Carolina State Univ., Raleigh, NC (United States)

    1996-04-01

    The Great Plains low-level jet (LLJ) is an important element of the low-level atmospheric circulation. It transports water vapor from the Gulf of Mexico, which in turn affects the development of weather over the Great Plains of the central United States. The LLJ is generally recognized as a complex response of the atmospheric boundary layer to the diurnal cycle of thermal forcing. Early studies have attributed the Great Plains LLJ to the diurnal oscillations of frictional effect, buoyancy over sloping terrain, and the blocking effects of the Rocky Mountains. Recent investigations show that the speed of the LLJ is also affected by the soil type and soil moisture. Some studies also suggest that synoptic patterns may play an important role in the development of the LLJ. Land surface heterogeneties significantly affect mesoscale circulations by generating strong contrasts in surface thermal fluxes. Thus one would expect that the land use pattern should have effects on the LLJ`s development and structure. In this study, we try to determine the relative roles of the synoptic forcing, planetary boundary layers (PBL) processes, and the land use pattern in the formation of the LLJ using the observations from the Atmospheric Radiation Measurement (ARM) Intensive Operation Period (IOP)-4 and numerical sensitivity tests.

  4. Can α-tocopherol and β-carotene supplementation reduce adverse radiation effects on salivary glands?

    International Nuclear Information System (INIS)

    Funegaard, U.; Johansson, I.; Ericson, T.; Malmer, B.; Henriksson, R.

    1995-01-01

    In this study, we evaluated whether supplementation with antioxidant vitamins can reduce the adverse effects of irradiation on the salivary glands in the rat. Four groups of adult Sprague-Dawley rats were given a basic diet providing 0.6 mg α-tocopherol and no β-carotene per day. In two groups the basic diet was supplemented with 3.4 mg α-tocopherol and 6 mg β-carotene per day from 14 days before irradiation until 12 days after complete irradiation. One group of rats given basic diet and one group given supplemented diet were irradiated with 7 Gy daily for five consecutive days. Isoproterenol and pilocarpine-stimulated whole saliva was collected from all rats 2, 4 and 26 weeks after irradiation. Vitamin-supplemented irradiated rats had higher secretion rates on all three occasions compared with those of irradiated rats given basic diet. The changes in saliva composition seen in irradiated rats were less accentuated in vitamin-supplemented, irradiated rats. The proportions of acinar cells were significantly decreased both in parotid and submandibular glands 26 weeks after irradiation. Supplementation with α-tocopherol and β-carotene did not alter the morphology of the glands. (author)

  5. Reducing abdominal CT radiation dose with the adaptive statistical iterative reconstruction technique in children: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Vorona, Gregory A. [The Children' s Hospital of Pittsburgh of UPMC, Department of Radiology, Pittsburgh, PA (United States); Allegheny General Hospital, Department of Radiology, Pittsburgh, PA (United States); Ceschin, Rafael C.; Clayton, Barbara L.; Sutcavage, Tom; Tadros, Sameh S.; Panigrahy, Ashok [The Children' s Hospital of Pittsburgh of UPMC, Department of Radiology, Pittsburgh, PA (United States)

    2011-09-15

    The use of the adaptive statistical iterative reconstruction (ASIR) algorithm has been shown to reduce radiation doses in adults undergoing abdominal CT studies while preserving image quality. To our knowledge, no studies have been done to validate the use of ASIR in children. To retrospectively evaluate differences in radiation dose and image quality in pediatric CT abdominal studies utilizing 40% ASIR compared with filtered-back projection (FBP). Eleven patients (mean age 8.5 years, range 2-17 years) had separate 40% ASIR and FBP enhanced abdominal CT studies on different days between July 2009 and October 2010. The ASIR studies utilized a 38% mA reduction in addition to our pediatric protocol mAs. Study volume CT dose indexes (CTDI{sub vol}) and dose-length products (DLP) were recorded. A consistent representative image was obtained from each study. The images were independently evaluated by two radiologists in a blinded manner for diagnostic utility, image sharpness and image noise. The average CTDI{sub vol} and DLP for the 40% ASIR studies were 4.25 mGy and 185.04 mGy-cm, compared with 6.75 mGy and 275.79 mGy-cm for the FBP studies, representing 37% and 33% reductions in both, respectively. The radiologists' assessments of subjective image quality did not demonstrate any significant differences between the ASIR and FBP images. In our experience, the use of 40% ASIR with a 38% decrease in mA lowers the radiation dose for children undergoing enhanced abdominal examinations by an average of 33%, while maintaining diagnostically acceptable images. (orig.)

  6. Reducing abdominal CT radiation dose with the adaptive statistical iterative reconstruction technique in children: a feasibility study

    International Nuclear Information System (INIS)

    Vorona, Gregory A.; Ceschin, Rafael C.; Clayton, Barbara L.; Sutcavage, Tom; Tadros, Sameh S.; Panigrahy, Ashok

    2011-01-01

    The use of the adaptive statistical iterative reconstruction (ASIR) algorithm has been shown to reduce radiation doses in adults undergoing abdominal CT studies while preserving image quality. To our knowledge, no studies have been done to validate the use of ASIR in children. To retrospectively evaluate differences in radiation dose and image quality in pediatric CT abdominal studies utilizing 40% ASIR compared with filtered-back projection (FBP). Eleven patients (mean age 8.5 years, range 2-17 years) had separate 40% ASIR and FBP enhanced abdominal CT studies on different days between July 2009 and October 2010. The ASIR studies utilized a 38% mA reduction in addition to our pediatric protocol mAs. Study volume CT dose indexes (CTDI vol ) and dose-length products (DLP) were recorded. A consistent representative image was obtained from each study. The images were independently evaluated by two radiologists in a blinded manner for diagnostic utility, image sharpness and image noise. The average CTDI vol and DLP for the 40% ASIR studies were 4.25 mGy and 185.04 mGy-cm, compared with 6.75 mGy and 275.79 mGy-cm for the FBP studies, representing 37% and 33% reductions in both, respectively. The radiologists' assessments of subjective image quality did not demonstrate any significant differences between the ASIR and FBP images. In our experience, the use of 40% ASIR with a 38% decrease in mA lowers the radiation dose for children undergoing enhanced abdominal examinations by an average of 33%, while maintaining diagnostically acceptable images. (orig.)

  7. Protection of Nitrate-Reducing Fe(II)-Oxidizing Bacteria from UV Radiation by Biogenic Fe(III) Minerals

    Science.gov (United States)

    Gauger, Tina; Konhauser, Kurt; Kappler, Andreas

    2016-04-01

    Due to the lack of an ozone layer in the Archean, ultraviolet radiation (UVR) reached early Earth's surface almost unattenuated; as a consequence, a terrestrial biosphere in the form of biological soil crusts would have been highly susceptible to lethal doses of irradiation. However, a self-produced external screen in the form of nanoparticular Fe(III) minerals could have effectively protected those early microorganisms. In this study, we use viability studies by quantifying colony-forming units (CFUs), as well as Fe(II) oxidation and nitrate reduction rates, to show that encrustation in biogenic and abiogenic Fe(III) minerals can protect a common soil bacteria such as the nitrate-reducing Fe(II)-oxidizing microorganisms Acidovorax sp. strain BoFeN1 and strain 2AN from harmful UVC radiation. Analysis of DNA damage by quantifying cyclobutane pyrimidine dimers (CPD) confirmed the protecting effect by Fe(III) minerals. This study suggests that Fe(II)-oxidizing microorganisms, as would have grown in association with mafic and ultramafic soils/outcrops, would have been able to produce their own UV screen, enabling them to live in terrestrial habitats on early Earth.

  8. N-acetyl Cysteine Reduced Oxidative Damages in Guinea Pigs Exposed to Cigarette Smoke and / or Gamma Radiation

    International Nuclear Information System (INIS)

    Ibrahim, N.K.; Abd-EL Aziz, N.; El-Deghidy, E.A.

    2010-01-01

    The objective of this study was to evaluate the role of n-acetyl cysteine (NAC) supplementation on oxidative cigarette smoke induced-oxidative damage in irradiated guinea pigs. N-acetyl cysteine was injected (i.p) to guinea pigs at a dose of 150 mg/kg b. w/day pre-exposure to cigarette smoke for one hour daily for 30 successive days. Animals were submitted to fractionate whole body gamma radiation (2 Gy installment every two weeks up to 4 Gy total dose started on the 2nd week of the experiment). Animals were sacrificed during the first hours from the last treatment of cigarette smoke. The results obtained showed significant increase in malondialdehyde (MDA) content associated with decreased superoxide dismutase (SOD) activity and glutathione (GSH) concentration in cardiac and pulmonary tissues as compared with their equivalent in control animals. The activities of lactate dehydrogenase (LDH), creatine phosphokinase (CPK), aspartate transaminase (AST), concentration of nitric oxide (NO), total cholesterol, Triacylglycerol, LDL-cholesterol were significant increased in plasma associated with significant decreased HDL-cholesterol. The administration of NAC has significantly attenuated the cigarette smoke and/or irradiation-induced changes in all the studied parameters. It could be concluded that NAC reduced cigarette smoke and radiation hazards via neutralized their capability to generate excessive reactive oxygen species (ROS) and free radicals in the biological systems

  9. Radiations

    International Nuclear Information System (INIS)

    Pujol Mora, J.

    1999-01-01

    The exposition to ionizing radiations is a constant fact in the life of the human being and its utilization as diagnostic and therapeutic method is generalized. However, it is notorious how as years go on, the fear to the ionizing radiation seems to persist too, and this fact is not limited to the common individual, but to the technical personnel and professional personnel that labors with them same. (S. Grainger) [es

  10. Radiation

    International Nuclear Information System (INIS)

    Davidson, J.H.

    1986-01-01

    The basic facts about radiation are explained, along with some simple and natural ways of combating its ill-effects, based on ancient healing wisdom as well as the latest biochemical and technological research. Details are also given of the diet that saved thousands of lives in Nagasaki after the Atomic bomb attack. Special comment is made on the use of radiation for food processing. (U.K.)

  11. A Randomized Controlled Trial of Lorazepam to Reduce Liver Motion in Patients Receiving Upper Abdominal Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Derek S.; Voncken, Francine E.M.; Tse, Regina V. [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Sykes, Jenna [Department of Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto (Canada); Wong, Rebecca K.S.; Dinniwell, Rob E.; Kim, John; Ringash, Jolie; Brierley, James D.; Cummings, Bernard J.; Brade, Anthony [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada); Dawson, Laura A., E-mail: laura.dawson@rmp.uhn.on.ca [Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Toronto (Canada)

    2013-12-01

    Purpose: Reduction of respiratory motion is desirable to reduce the volume of normal tissues irradiated, to improve concordance of planned and delivered doses, and to improve image guided radiation therapy (IGRT). We hypothesized that pretreatment lorazepam would lead to a measurable reduction of liver motion. Methods and Materials: Thirty-three patients receiving upper abdominal IGRT were recruited to a double-blinded randomized controlled crossover trial. Patients were randomized to 1 of 2 study arms: arm 1 received lorazepam 2 mg by mouth on day 1, followed by placebo 4 to 8 days later; arm 2 received placebo on day 1, followed by lorazepam 4 to 8 days later. After tablet ingestion and daily radiation therapy, amplitude of liver motion was measured on both study days. The primary outcomes were reduction in craniocaudal (CC) liver motion using 4-dimensional kV cone beam computed tomography (CBCT) and the proportion of patients with liver motion ≤5 mm. Secondary endpoints included motion measured with cine magnetic resonance imaging and kV fluoroscopy. Results: Mean relative and absolute reduction in CC amplitude with lorazepam was 21% and 2.5 mm respectively (95% confidence interval [CI] 1.1-3.9, P=.001), as assessed with CBCT. Reduction in CC amplitude to ≤5 mm residual liver motion was seen in 13% (95% CI 1%-25%) of patients receiving lorazepam (vs 10% receiving placebo, P=NS); 65% (95% CI 48%-81%) had reduction in residual CC liver motion to ≤10 mm (vs 52% with placebo, P=NS). Patients with large respiratory movement and patients who took lorazepam ≥60 minutes before imaging had greater reductions in liver CC motion. Mean reductions in liver CC amplitude on magnetic resonance imaging and fluoroscopy were nonsignificant. Conclusions: Lorazepam reduces liver motion in the CC direction; however, average magnitude of reduction is small, and most patients have residual motion >5 mm.

  12. Radiolabeling optimization and reduced staff radiation exposure for high-dose 90Y-ibritumomab tiuxetan (HD-Zevalin)

    International Nuclear Information System (INIS)

    Papi, Stefano; Martano, Luigi; Garaboldi, Lucia; Rossi, Annalisa; Cremonesi, Marta; Grana, Chiara Maria; Paolucci, Daniele; Sansovini, Maddalena; Paganelli, Giovanni; Chinol, Marco

    2010-01-01

    Introduction: 90 Y-Zevalin labeling may cause severe finger radiation exposure, especially in high-dose protocols (HD-Zevalin), where up to 7.4 GBq could be injected. In this work, we optimized the labeling of HD-Zevalin with special regard to simplicity, speed, safety and radiation protection. Methods: Factors influencing labeling outcome (activity, specific activity, time, final volume, stability) were studied separately. The critical steps of a standard radiolabeling procedure were optimized to reduce finger exposure, developing an alternative labeling procedure and including a different 90 Y supplier. Finger doses were monitored by thermoluminescent dosimeters at each fingertip under anti-X gloves, considering both absolute values and values after normalization to 1.48 GBq. Results: Labeling of 90 Y-Zevalin was safe and reproducible up to 7.4 GBq with a simple and single-step procedure offering good stability for several hours. Radiolabeling specific activity was found critical, being kept at 740 MBq.mg -1 . Radiochemical purity values ≥98% were routinely achieved. The alternative procedure allowed a sensible reduction of finger dose, due to both the different 90 Y vial and the handling. Finger exposure was reduced from 6.6±4.3 to 3.1±0.8 mSv/1.48 GBq in the case of the original 90 Y vial and from 1.5±0.9 to 0.3±0.1 mSv/1.48 GBq using a shielded 90 Y vial. Conclusions: HD-Zevalin can be prepared in a safe and reproducible way, giving high radiochemical purity values, good stability and low finger exposure. This study may improve the safety of nuclear medicine professionals involved in the preparation of Zevalin.

  13. Radiation

    International Nuclear Information System (INIS)

    Winther, J.F.; Ulbak, K.; Dreyer, L.; Pukkala, E.; Oesterlind, A.

    1997-01-01

    Exposure to solar and ionizing radiation increases the risk for cancer in humans. Some 5% of solar radiation is within the ultraviolet spectrum and may cause both malignant melanoma and non-melanocytic skin cancer; the latter is regarded as a benign disease and is accordingly not included in our estimation of avoidable cancers. Under the assumption that the rate of occurrence of malignant melanoma of the buttocks of both men and women and of the scalp of women would apply to all parts of the body in people completely unexposed to solar radiation, it was estimated that approximately 95% of all malignant melanomas arising in the Nordic populations around the year 2000 will be due to exposure to natural ultraviolet radiation, equivalent to an annual number of about 4700 cases, with 2100 in men and 2600 in women, or some 4% of all cancers notified. Exposure to ionizing radiation in the Nordic countries occurs at an average effective dose per capita per year of about 3 mSv (Iceland, 1.1 mSv) from natural sources, and about 1 mSv from man-made sources. While the natural sources are primarily radon in indoor air, natural radionuclides in food, cosmic radiation and gamma radiation from soil and building materials, the man-made sources are dominated by the diagnostic and therapeutic use of ionizing radiation. On the basis of measured levels of radon in Nordic dwellings and associated risk estimates for lung cancer derived from well-conducted epidemiological studies, we estimated that about 180 cases of lung cancer (1% of all lung cancer cases) per year could be avoided in the Nordic countries around the year 2000 if indoor exposure to radon were eliminated, and that an additional 720 cases (6%) could be avoided annually if either radon or tobacco smoking were eliminated. Similarly, it was estimated that the exposure of the Nordic populations to natural sources of ionizing radiation other than radon and to medical sources will each give rise to an annual total of 2120

  14. A radiation protection training program designed to reduce occupational radiation dose to individuals using pneumatic-transfer systems at the Oregon State TRIGA reactor

    International Nuclear Information System (INIS)

    Johnson, A.G.; Anderson, T.V.; Pratt, D.; Dodd, B.; Carpenter, W.T.

    1984-01-01

    In order to keeping personnel doses as low as reasonably achievable, and also to help satisfy requirements of NRC regulations contained in 10 CFR 19, a training program was established to qualify all individuals prior to their use of the OSTR PT systems. Program objectives are directed mainly towards minimizing the spread of radioactive contamination and reducing the potential for unnecessary and inappropriate personnel radiation exposure; however, other operational and emergency procedures are also covered. The PT systems training program described in this report was established approximately 8 to 10 years ago but recently there was an increased interest to use it. Whether or not a PT system training program should be implemented at a specific TRIGA operation (assuming the facility is equipped with a PT system) will undoubtedly be influenced heavily by the nature and frequency of the PT system's use, by who uses the system, and by whether the system is one of the automatic loading and unloading types, or one of the more' commonly encountered manually operated systems. However, from our experience we feel that training commensurate with the type of PT system operation being conducted is a wise investment, and should be a requirement for all system operators

  15. Great Lakes Science Center

    Data.gov (United States)

    Federal Laboratory Consortium — Since 1927, Great Lakes Science Center (GLSC) research has provided critical information for the sound management of Great Lakes fish populations and other important...

  16. Radiation-induced G/sub 2/-arrest is reduced by inhibitors of poly(adenosine diphosphoribose) synthetase

    International Nuclear Information System (INIS)

    Rowley, R.

    1985-01-01

    Experiments are in progress to test whether poly(adenosine diphosphoribose) synthesis is required for the induction of G/sub 2/-arrest in growing mammalian cells following X-irradiation. A variety of poly(ADPR) synthetase inhibitors have been tested to determine: 1) whether addition of an inhibitor to X-irradiated CHO cells reduces G/sub 2/-arrest; 2) whether compounds structurally similar to poly-(ADPR) synthetase inhibitors but inactive against this enzyme affect radiation-induced G/sub 2/-arrest and 3) whether the concentration dependence for poly(ADPR) synthetase inhibition matches that for G/sub 2/-arrest reduction. G/sub 2/-arrest was measured in X-irradiated (1.5 Gy) CHO cells using the mitotic cell selection technique. Poly(ADPR) synthetase activity was measured in permeabilized cells by /sup 3/H-NAD incorporation. The synthetase inhibitors used were 3-aminobenzamide, benzamide, nicotinamide, 4-acetyl pyridine, caffeine and theophylline. The inactive compounds used were 3-aminobenzoic acid, benzoic acid, nicotinic acid, adenine, adenosine and 3'-deoxyadenosine. Inhibitors of poly(ADPR) synthetase reduced G/sub 2/-arrest while related compounds which produced no enzyme inhibition did not. The concentration dependencies for G/sub 2/-arrest reduction and enzyme inhibition were similar only for methyl xanthines. Further analysis awaits the determination of intracellular drug concentrations

  17. Myocardial hydroxyproline reduced by early administration of methylprednisolone or ibuprofen to rabbits with radiation-induced heart disease

    International Nuclear Information System (INIS)

    Reeves, W.C.; Cunningham, D.; Schwiter, E.J.; Abt, A.; Skarlatos, S.; Wood, M.A.; Whitesell, L.

    1982-01-01

    The ability of methylprednisolone (MP) and ibuprofen (IB) to reduce the severity of the late state of radiation-induced heart disease was assessed in 57 New Zealand white rabbits. Before and shortly after cardiac irradiation, 15 rabbits received i.v. MP, 30 mg/kg twice daily for 3 days, and 15 others received IB, 12.5 mg/kg twice daily for 2 days. No drug administered to 14 irradiated rabbits, and neither irradiation nor drugs were administered to 13 rabbits that served as controls. All 15 rabbits treated with MP and 13 of the 15 treated with IB lived for 100 days. Only seven of the untreated, irradiated rabbits lived that long. Longevity of each treated group of rabbits was better (p < 0.01 and 0.05) than that of the untreated, irradiated rabbits. Surviving rabbits were killed 100 days after irradiation. Pericarditis (p < 0.05) and pericardial effusion (p < 0.01) were less frequent in the treated, irradiated groups than in the untreated, irradiated rabbits. At least some rabbits in each irradiated group had microscopic evidence of myocardial fibrosis. The fibrosis was quantitated by determination of myocardial hydroxyproline concentrations (MHP). MHP concentration in the untreated, irradiated rabbits was greater than in those treated with MP (p < 0.05) or IB (p < 0.01) and in the untreated, unirradiated rabbits (p < 0.01). Early administrative of MP or IB retarded the development of myocardial fibrosis, pericarditis and pericardial effusin, and improved survival in this experimental model of radiation-induced heart disease

  18. Myocardial hydroxyproline reduced by early administration of methylprednisolone or ibuprofen to rabbits with radiation-induced heart disease

    International Nuclear Information System (INIS)

    Reeves, W.C.; Cunningham, D.; Schwiter, E.J.; Abt, A.; Skarlatos, S.; Wood, M.A.; Whitesell, L.

    1982-01-01

    The ability of methylprednisolone (MP) and ibuprofen (IB) to reduce the severity of the late state of radiation-induced heart disease was assessed in 57 New Zealand white rabbits. Before and shortly after cardiac irradiation, 15 rabbits received i.v. MP, 30 mg/kg twice daily for 3 days, and 15 others received IB, 12.5 mg/kg twice daily for 2 days. No drug was administered to 14 irradiated rabbits, and neither irradiation nor drugs were administered to 13 rabbits that served as controls, All 15 rabbits treated with MP and 13 of the 15 treated with IB lived for 100 days. Only seven of the untreated, irradiated rabbits lived that long. Longevity of each treated group of rabbits was better (p less than 0.01 and 0.05) than that of the untreated, irradiated rabbits. Surviving rabbits were killed 100 days after irradiation. Pericarditis (p less than 0.05) and pericardial effusion (p less than 0.01) were less frequent in the treated, irradiated groups than in the untreated, irradiated rabbits. At least some rabbits in each irradiated group had microscopic evidence of myocardial fibrosis. The fibrosis was quantitated by determination of myocardial hydroxyproline concentrations (MHP). MHP concentration in the untreated, irradiated rabbits was greater than in those treated with MP (p less than 0.05) or IB (p less than 0.01) and in the untreated, unirradiated rabbits (p less than 0.01). Early administration of MP or IB retarded the development of myocardial fibrosis, pericarditis and pericardial effusion, and improved survival in this experimental model of radiation-induced heart disease

  19. Development and demonstration of surveillance and diagnostics of rotating machinery for reducing radiation exposure to nuclear power plant personnel: Appendices: Final report

    International Nuclear Information System (INIS)

    Allen, J.W.; Bohanick, J.S.

    1988-01-01

    This program was designed to reduce radiation exposure to power plant personnel resulting from inspection, maintenance, and repair of rotating equipment. The new rotating machinery monitoring system for this program was installed at GGNS during August 1983. The following nine appendices are presented: signals monitored at GGNS; definition of characterized spectral values; instructions for alignment and balance programs; machine diagrams; FFT program; software module descriptions; sample radiation survey forms used for exposure study; radiation exposure compared to other plants; and a technical section instruction for the vibration monitoring program at GGNS

  20. Southern Great Plains Safety Orientation

    Energy Technology Data Exchange (ETDEWEB)

    Schatz, John

    2014-05-01

    Welcome to the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ARM) Southern Great Plains (SGP) site. This U.S. Department of Energy (DOE) site is managed by Argonne National Laboratory (ANL). It is very important that all visitors comply with all DOE and ANL safety requirements, as well as those of the Occupational Safety and Health Administration (OSHA), the National Fire Protection Association, and the U.S. Environmental Protection Agency, and with other requirements as applicable.

  1. Characteristics of a New X-Ray Imaging System for Interventional Procedures: Improved Image Quality and Reduced Radiation Dose.

    Science.gov (United States)

    Schernthaner, Ruediger E; Haroun, Reham R; Nguyen, Sonny; Duran, Rafael; Sohn, Jae Ho; Sahu, Sonia; Chapiro, Julius; Zhao, Yan; Radaelli, Alessandro; van der Bom, Imramsjah M; Mauti, Maria; Hong, Kelvin; Geschwind, Jean-François H; Lin, MingDe

    2018-03-01

    To compare image quality and radiation exposure between a new angiographic imaging system and the preceding generation system during uterine artery embolization (UAE). In this retrospective, IRB-approved two-arm study, 54 patients with symptomatic uterine fibroids were treated with UAE on two different angiographic imaging systems. The new system includes optimized acquisition parameters and real-time image processing algorithms. Air kerma (AK), dose area product (DAP) and acquisition time for digital fluoroscopy (DF) and digital subtraction angiography (DSA) were recorded. Body mass index was noted as well. DF image quality was assessed objectively by image noise measurements. DSA image quality was rated by two blinded, independent readers on a four-rank scale. Statistical differences were assessed with unpaired t tests and Wilcoxon rank-sum tests. There was no significant difference between the patients treated on the new (n = 36) and the old system (n = 18) regarding age (p = 0.10), BMI (p = 0.18), DF time (p = 0.35) and DSA time (p = 0.17). The new system significantly reduced the cumulative AK and DAP by 64 and 72%, respectively (median 0.58 Gy and 145.9 Gy*cm 2 vs. 1.62 Gy and 526.8 Gy*cm 2 , p < 0.01 for both). Specifically, DAP for DF and DSA decreased by 59% (75.3 vs. 181.9 Gy*cm 2 , p < 0.01) and 78% (67.6 vs. 312.2 Gy*cm 2 , p < 0.01), respectively. The new system achieved a significant decrease in DF image noise (p < 0.01) and a significantly better DSA image quality (p < 0.01). The new angiographic imaging system significantly improved image quality and reduced radiation exposure during UAE procedures.

  2. Isolation and characterization of human salivary gland cells for stem cell transplantation to reduce radiation-induced hyposalivation

    International Nuclear Information System (INIS)

    Feng Jielin; Zwaag, Marianne van der; Stokman, Monique A.; Os, Ronald van; Coppes, Robert P.

    2009-01-01

    Background: Recently, we showed that transplantation of 100-300 c-Kit + stem cells isolated from cultured salispheres ameliorates radiation-damage in murine salivary glands. The aim of this study is to optimize and translate these findings from mice to man. Methods: Mouse and human non-malignant parotid and submandibular salivary gland tissue was collected and enzymatically digested. The remaining cell suspension was cultured according to our salisphere culture method optimized for murine salispheres. Salisphere cells were tested using 3D matrix culturing for their in vitro stem cell characteristics such as the potential to differentiate into tissue specific cell types. Several potential mouse and human salivary gland stem cells were selected using FACS. Results: In human salivary gland, c-Kit + cells were only detected in excretory ducts as shown previously in mice. From both human parotid and submandibular gland cell suspensions salispheres could be grown, which when placed in 3D culture developed ductal structures and mucin-expressing acinar-like cells. Moreover, cells dispersed from primary salispheres were able to form secondary spheres in matrigel, a procedure that could be repeated for at least seven passages. Approximately 3000 c-Kit + cells could be isolated from primary human salispheres per biopsy. Conclusion: Human salivary glands contain a similar 'putative' stem cell population as rodents, expressing c-kit and capable of in vitro differentiation and self-renewal. In the future, these cells may have the potential to reduce radiotherapy-induced salivary gland dysfunction in patients.

  3. The effectiveness of various decontamination techniques for reducing external radiation doses to people living in an urban environment

    International Nuclear Information System (INIS)

    Brown, J.; Crick, M.J.; Hill, M.D.

    1988-01-01

    The NRPB has recently developed a dynamic model, EXPURT (EXPosure from Urban Radionuclide Transfer), that reflects the transfer processes that take place in the urban environment. Parameter values for the model have been derived from experiments performed in recent years in the United Kingdom and in Denmark. The model incorporates shielding properties of different types of buildings, and population habits to evaluate individual and population doses as a function of time after deposit. The original model has been extended to enable it to represent several techniques for decontaminating the various surfaces in the urban environment. These include hosing of impermeable surfaces, such as walls, roofs and paved areas, the removal or ploughing of soil/grass, and the replacement of building surfaces with new uncontaminated materials. The model has been used to examine the effectiveness of these various decontamination measures at reducing the external radiation doses to people living in urban areas. The importance of the time at which decontamination is performed is also discussed in this paper

  4. Prophylactic Treatment with Adlay Bran Extract Reduces the Risk of Severe Acute Radiation Dermatitis: A Prospective, Randomized, Double-Blind Study

    Directory of Open Access Journals (Sweden)

    Chih-Jen Huang

    2015-01-01

    Full Text Available Acute radiation dermatitis is a frequent adverse effect in patients with breast cancer undergoing radiotherapy, but there are only a small number of studies providing evidence-based interventions for this clinical condition. Adlay is a cereal crop that has been previously shown to have anti-inflammatory and antioxidant properties. In this study, we seek to evaluate the effectiveness of oral prophylactic treatment with adlay bran extract in reducing the risk of severe acute radiation dermatitis. A total of 110 patients with breast cancer undergoing radiotherapy were analyzed. Using a prospective, randomized, double-blind design, 73 patients received oral treatment with adlay bran extract and 37 patients received olive oil (placebo. Treatment was started at the beginning of radiation therapy and continued until the termination of radiation treatment. Our results showed that the occurrence of severe acute radiation dermatitis (RTOG grade 2 or higher was significantly lower in patients treated with oral adlay bran extract compared to placebo (45.2% versus 75.7%, adjusted odds ratio 0.24. No serious adverse effects from adlay bran treatment were noted. In conclusion, prophylactic oral treatment with adlay bran extract reduces the risk of severe acute radiation dermatitis and may have potential use in patients with breast cancer undergoing radiotherapy.

  5. A survey of techniques to reduce and manage external beam radiation-induced xerostomia in British oncology and radiotherapy departments

    International Nuclear Information System (INIS)

    Macknelly, Andrew; Day, Jane

    2009-01-01

    ? - A feasibility study for locally advanced head and neck cancer patients treated with intensity-modulated radiotherapy. Clinical Oncology 2006;18(6):497-504, Braam P, Terhaard C, Roesnink J, Cornelis P, Raaijmakers C. Intensity-modulated radiotherapy significantly reduces xerostomia compared with conventional radiotherapy. International Journal of Radiation Oncology, Biology and Physics 2006, Wendt TG, Abbasi-Senger N, Salz H, Pinquart I, Koscelny S, Przetak S, et al. 3D-conformal-intensity modulated radiotherapy with compensators for head and neck cancer: clinical results of normal tissue sparing. Radiation Oncology 2006;1:18. Available from: (http://www.ro-journal.com/content/1/1/18) [accessed on 21.11.06].]. This, in turn, offers increased normal tissue sparing than conventional radiotherapy [Ng M, Porceddu S, Milner A, Corry J, Hornby C, Hope G, et al. Parotid-sparing radiotherapy: does it really reduce xerostomia? Clinical Oncology 2005;17(8):610-7.]. The survey indicated that all three techniques, however, are still in use in oncology and radiotherapy departments, and several departments stated that financial considerations were hindering their move toward providing IMRT.

  6. Reducing radiation dose in 64-row spiral CT coronary angiography: study based on individualized scan dosage protocol

    International Nuclear Information System (INIS)

    Kang Deqiang; Zhao Jing; Peng Nan; Hua Haiqin; Li Chao; Guo Ying; Shen Yun

    2012-01-01

    Objective: To investigate the methods of reducing radiation dose in CT coronary angiography through optimizing individualized scan dosage protocol. Methods: Two hundred patients (group A) underwent coronary CTA examination which was performed with fixed 120 kV and variable mA according to their BMI. The mA was set as 150-300 mA (BMI < 18.5 kg/m2), 300-500 mA (18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 ), and 500-800 mA (BMI ≥ 25.0 kg/m 2 ). When all examinations were finished, a linear regression was employed to analyze the correlation between mA and BMI, body surface (Suf), image noise (SD) respectively. The results of the analysis were used to formulate a regression equation, which was further used to establish a table list for quick search on how much mA that individualized coronary CTA scan would need. Another 200 patients (group B) enrolled for the individualized scan were scanned under new protocol that previous study established. The tube voltage was 100 and 120 kV. The tube current was variable according to the data in the table list. One-way ANOVA and Kruskal-wallis H test were used for statistics. Results: Regression equation between mA and BMI, Suf, SD was: mA =17.984 × BMI + 169.149 × Suf-2.282 × SD-361.039. The SD (group A: 32.08 ± 5.80, group B: 28.60±4.47), dose index volume (CTDI vol ) [group A: (41.97 ± 11.37) mGy, group B: (33.18±10.07) mGy], effective dose(ED) [group A: (10.91 ±3.07) mSy, group B: (8.83 ±2.72)mSv] had significant differences between the two groups (F=43.45, 63.71, 49.07 respectively, P<0.01 for all). The SD and ED results obtained in group B were better than those in group A. Conclusion: Better performances were obtained when BMI combined Suf was used as a new individualized protocol than when BMI was used only, which means good image quality and lower radiation dosage in coronary CTA examination. (authors)

  7. Leaded eyeglasses substantially reduce radiation exposure of the surgeon's eyes during acquisition of typical fluoroscopic views of the hip and pelvis.

    Science.gov (United States)

    Burns, Sean; Thornton, Raymond; Dauer, Lawrence T; Quinn, Brian; Miodownik, Daniel; Hak, David J

    2013-07-17

    Despite recommendations to do so, few orthopaedists wear leaded glasses when performing operative fluoroscopy. Radiation exposure to the ocular lens causes cataracts, and regulatory limits for maximum annual occupational exposure to the eye continue to be revised downward. Using anthropomorphic patient and surgeon phantoms, radiation dose at the surgeon phantom's lens was measured with and without leaded glasses during fluoroscopic acquisition of sixteen common pelvic and hip views. The magnitude of lens dose reduction from leaded glasses was calculated by dividing the unprotected dose by the dose measured behind leaded glasses. On average, the use of leaded glasses reduced radiation to the surgeon phantom's eye by tenfold, a 90% reduction in dose. However, there was widespread variation in the amount of radiation that reached the phantom surgeon's eye among the various radiographic projections we studied. Without leaded glasses, the dose measured at the surgeon's lens varied more than 250-fold among these sixteen different views. In addition to protecting the surgeon's eye from the deleterious effects of radiation, the use of leaded glasses could permit an orthopaedist to perform fluoroscopic views on up to ten times more patients before reaching the annual dose limit of 20 mSv of radiation to the eye recommended by the International Commission on Radiological Protection. Personal safety and adherence to limits of occupational radiation exposure should compel orthopaedists to wear leaded glasses for fluoroscopic procedures if other protective barriers are not in use. Leaded glasses are a powerful tool for reducing the orthopaedic surgeon's lens exposure to radiation during acquisition of common intraoperative fluoroscopic views.

  8. Mechanism of Action for Anti-radiation Vaccine in Reducing the Biological Impact of High-dose Gamma Irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    2007-01-01

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then collected and circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naive animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. Initial analysis of the biochemical characteristics indicated that the SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which the mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  9. Mechanism of action for anti-radiation vaccine in reducing the biological impact of high-dose gamma irradiation

    Science.gov (United States)

    Maliev, Vladislav; Popov, Dmitri; Jones, Jeffrey A.; Casey, Rachael C.

    Ionizing radiation is a major health risk of long-term space travel, the biological consequences of which include genetic and oxidative damage. In this study, we propose an original mechanism by which high doses of ionizing radiation induce acute toxicity. We identified biological components that appear in the lymphatic vessels shortly after high-dose gamma irradiation. These radiation-induced toxins, which we have named specific radiation determinants (SRD), were generated in the irradiated tissues and then circulated throughout the body via the lymph circulation and bloodstream. Depending on the type of SRD elicited, different syndromes of acute radiation sickness (ARS) were expressed. The SRDs were developed into a vaccine used to confer active immunity against acute radiation toxicity in immunologically naïve animals. Animals that were pretreated with SRDs exhibited resistance to lethal doses of gamma radiation, as measured by increased survival times and survival rates. In comparison, untreated animals that were exposed to similar large doses of gamma radiation developed acute radiation sickness and died within days. This phenomenon was observed in a number of mammalian species. Initial analysis of the biochemical characteristics indicated that the SRDs were large molecular weight (200-250 kDa) molecules that were comprised of a mixture of protein, lipid, carbohydrate, and mineral. Further analysis is required to further identify the SRD molecules and the biological mechanism by which they mediate the toxicity associated with acute radiation sickness. By doing so, we may develop an effective specific immunoprophylaxis as a countermeasure against the acute effects of ionizing radiation.

  10. Radiation shielding concrete

    International Nuclear Information System (INIS)

    Kunishima, Shigeru.

    1990-01-01

    The radiation shielding concretes comprise water, cement, fine aggregates consisting of serpentines and blown mist slags, coarse aggregates consisting of serpentines and kneading materials. Since serpentines containing a relatively great amount of water of crystallization in rocks as coarse aggregates and fine aggregates, the hydrogen content in the radiation shielding concretes is increased and the neutron shielding effect is improved. In addition, since serpentines are added as the fine aggregates and blown mists slags of a great specific gravity are used, the specific gravity of the shielding concretes is increased to improve the γ-ray shielding effect. Further, by the use of the kneading material having a water reducing effect and fluidizing effect, and by the bearing effect of the spherical blown mist slags used as the fine aggregates, concrete fluidity can be increased. Accordingly, workability of the radiation shielding concretes can be improved. (T.M.)

  11. Benefits of adopting good radiation practices in reducing the whole body radiation dose to the nuclear medicine personnel during (18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging.

    Science.gov (United States)

    Verma, Shashwat; Kheruka, Subhash Chand; Maurya, Anil Kumar; Kumar, Narvesh; Gambhir, Sanjay; Kumari, Sarita

    2016-01-01

    Positron emission tomography has been established as an important imaging modality in the management of patients, especially in oncology. The higher gamma radiation energy of positron-emitting isotopes poses an additional radiation safety problem. Those working with this modality may likely to receive higher whole body doses than those working only in conventional nuclear medicine. The radiation exposure to the personnel occurs in dispensing the dose, administration of activity, patient positioning, and while removing the intravenous (i.v.) cannula. The estimation of radiation dose to Nuclear Medicine Physician (NMP) involved during administration of activity to the patient and technical staff assisting in these procedures in a positron emission tomography/computed tomography (PET/CT) facility was carried out. An i.v access was secured for the patient by putting the cannula and blood sugar was monitored. The activity was then dispensed and measured in the dose calibrator and administered to the patient by NMP. Personnel doses received by NMP and technical staff were measured using electronic pocket dosimeter. The radiation exposure levels at various working locations were assessed with the help of gamma survey meter. The radiation level at working distance while administering the radioactivity was found to be 106-170 μSv/h with a mean value of 126.5 ± 14.88 μSv/h which was reduced to 4.2-14.2 μSv/h with a mean value of 7.16 ± 2.29 μSv/h with introduction of L-bench for administration of radioactivity. This shows a mean exposure level reduction of 94.45 ± 1.03%. The radiation level at working distance, while removing the i.v. cannula postscanning was found to be 25-70 μSv/h with a mean value of 37.4 ± 13.16 μSv/h which was reduced to 1.0-5.0 μSv/h with a mean value of 2.77 ± 1.3 μSv/h with introduction of L-bench for removal of i.v cannula. This shows a mean exposure level reduction of 92.85 ± 1.78%. This study shows that good radiation practices are

  12. Prophylactic vesical instillations with 0.2% chondroitin sulfate may reduce symptoms of acute radiation cystitis in patients undergoing radiotherapy for gynecological malignancies

    NARCIS (Netherlands)

    Hazewinkel, M.H.; Stalpers, L.J.A.; Dijkgraaf, M.G.; Roovers, J.P.W.R.

    2011-01-01

    We studied the feasibility and efficacy of intravesical instillations with 40 ml chondroitin sulfate 0.2% solution to prevent or reduce acute radiation cystitis in women undergoing pelvic radiotherapy. In a comparative pilot study in 20 patients, half of the patients received instillations.

  13. Reducing radiation dose in liver enhanced CT scan by setting mAs according to plain scan noise

    International Nuclear Information System (INIS)

    Yang Shangwen; He Jian; Yang Xianfeng; Zhou Kefeng; Xin Xiaoyan; Hu Anning; Zhu Bin

    2013-01-01

    Objective: To investigate the feasibility of setting mAs in liver enhanced CT scan according to plain scan noise with fixed mA CT scanner, in order to reduce the radiation dose. Methods: One hundred continuous patients underwent liver enhanced CT scan (group A) prospectively. Two hundred and fifty mAs was used in plain and enhanced CT scans. Noises of plain and venous phase CT images were measured, and the image quality was evaluated. The equation between mAs of enhanced scan and noise of plain scan image was derived. Another 100 continuous patients underwent liver enhanced CT scan (group B). Enhanced scan mAs was calculated from noise on plain scan by using the equation above. Noises on venous phase images were measured and the image quality was measured. Based on body mass index (BMI), patients in groups A and B were divided into three subgroups respectively: BMI < 18.5 kg/m 2 , 18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 and BMI ≥ 25.0 kg/m 2 . Image quality score was compared with nonparametric rank sum test, CT dose index (CTDI) and effective dose (ED) were measured and compared between each subgroup with 2 independent samples t or t' test. Results: The equation between enhanced scan mAs (mAsX) and plain scan noise (SDp) was as follows: mAsX = mAs1 × [(0.989 × SDp + 1.06) /SDx] 2 , mAs1 = 250 mAs, SDx = 13. In patients with BMI < 18.5 kg/m 2 , ED of group A [(6.86 ± 0.38) mSv, n = 12] was significantly higher than group B [(2.66 ± 0.46) mSv, n = 10)] (t = 18.52, P < 0.01). In patients with 18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 , ED of group A [(7.08 ± 0.91) mSv, n = 66] was significantly higher than group B [(4.50 ± 1.41) mSv, n = 73] (t' = 10.57, P < 0.01). In patients with BMI ≥ 25.0 kg/m 2 , there was no significant difference between EDs of group A (7.54 ± 0.62 mSv, n = 22) and group B [(8.19 ± 3.16) mSv, n = 17] (t' = 0.89, P = 0.39). Image quality of 5 patients in group A and none in group B did not meet the diagnostic requirement

  14. Reducing plant radiation fields by source term reduction - tracking cobalt and antimony to their sources at Gentilly-2

    International Nuclear Information System (INIS)

    Gauthier, P.; Guzonas, D.A.

    2006-01-01

    Gentilly-2 NGS is experiencing high radiation fields in the fuelling machine vaults. These high fields make maintenance outages more expensive and their management more complicated. As part of the station refurbishment project, a task group was created to identify the cause of the high fields and make recommendations to prevent their reoccurrence in the second (post-refurbishment) operating cycle. To identify the root cause of the problem, the task group decided to analyse the primary heat transport system (PHTS), the fuel handling system and their inter-relation. Gentilly-2 has had to manage a unique (to CANDU) problem arising from antimony released from the main heat transport pump seals. Antimony deposits on in-core surfaces, becomes activated, and subsequently can be released, especially under oxidizing coolant conditions. It then becomes incorporated into the magnetite deposits on PHTS piping, including the steam generators and inlet feeders. Gentilly-2 has focused a great deal of effort on managing antimony over the last 15 years. As a result of these initiatives, radioantimony fields have been quite effectively managed since 1997, resulting in a decrease in their relative contribution to the total fields. The decrease in radioantimony fields highlighted the significant contribution of 60 Co cobalt activity; the high levels of both radioantimony and 60 Co differentiate Gentilly-2 from other CANDU 6 plants. Two types of 59 Co sources are present in the CANDU PHTS. High surface area materials such as steam generator tubes and feeder pipes contain trace concentrations of 59 Co as an impurity, which can be released by corrosion. Low surface area materials such as Stellites contain high concentrations of 59 Co that can be released as either corrosion or wear products. After assessing potential cobalt sources, the task group concluded that PHTS materials were not likely the origin of the high 60 Co fields. The major PHTS components identified as cobalt sources have

  15. Reducing the Cost of Proton Radiation Therapy: The Feasibility of a Streamlined Treatment Technique for Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Newhauser, Wayne D., E-mail: newhauser@lsu.edu [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA 70803 (United States); Department of Physics, Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA 70809 (United States); Zhang, Rui [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA 70803 (United States); Department of Physics, Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA 70809 (United States); Departments of Radiation Physics and Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030 (United States); The University of Texas Graduate School of Biomedical Sciences, Houston, TX 77030 (United States); Jones, Timothy G. [Departments of Radiation Physics and Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030 (United States); The University of Texas Graduate School of Biomedical Sciences, Houston, TX 77030 (United States); Department of Physics, Abilene Christian University, ACU Box 27963, Abilene, TX 79699 (United States); Giebeler, Annelise; Taddei, Phillip J. [Departments of Radiation Physics and Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030 (United States); The University of Texas Graduate School of Biomedical Sciences, Houston, TX 77030 (United States); Stewart, Robert D. [Department of Radiation Oncology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 356043, Seattle, WA 98195 (United States); Lee, Andrew [Departments of Radiation Physics and Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030 (United States); Vassiliev, Oleg [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, LA 70803 (United States); Department of Physics, Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, LA 70809 (United States)

    2015-04-24

    Proton radiation therapy is an effective modality for cancer treatments, but the cost of proton therapy is much higher compared to conventional radiotherapy and this presents a formidable barrier to most clinical practices that wish to offer proton therapy. Little attention in literature has been paid to the costs associated with collimators, range compensators and hypofractionation. The objective of this study was to evaluate the feasibility of cost-saving modifications to the present standard of care for proton treatments for prostate cancer. In particular, we quantified the dosimetric impact of a treatment technique in which custom fabricated collimators were replaced with a multileaf collimator (MLC) and the custom range compensators (RC) were eliminated. The dosimetric impacts of these modifications were assessed for 10 patients with a commercial treatment planning system (TPS) and confirmed with corresponding Monte Carlo simulations. We assessed the impact on lifetime risks of radiogenic second cancers using detailed dose reconstructions and predictive dose-risk models based on epidemiologic data. We also performed illustrative calculations, using an isoeffect model, to examine the potential for hypofractionation. Specifically, we bracketed plausible intervals of proton fraction size and total treatment dose that were equivalent to a conventional photon treatment of 79.2 Gy in 44 fractions. Our results revealed that eliminating the RC and using an MLC had negligible effect on predicted dose distributions and second cancer risks. Even modest hypofractionation strategies can yield substantial cost savings. Together, our results suggest that it is feasible to modify the standard of care to increase treatment efficiency, reduce treatment costs to patients and insurers, while preserving high treatment quality.

  16. Reducing the Cost of Proton Radiation Therapy: The Feasibility of a Streamlined Treatment Technique for Prostate Cancer

    International Nuclear Information System (INIS)

    Newhauser, Wayne D.; Zhang, Rui; Jones, Timothy G.; Giebeler, Annelise; Taddei, Phillip J.; Stewart, Robert D.; Lee, Andrew; Vassiliev, Oleg

    2015-01-01

    Proton radiation therapy is an effective modality for cancer treatments, but the cost of proton therapy is much higher compared to conventional radiotherapy and this presents a formidable barrier to most clinical practices that wish to offer proton therapy. Little attention in literature has been paid to the costs associated with collimators, range compensators and hypofractionation. The objective of this study was to evaluate the feasibility of cost-saving modifications to the present standard of care for proton treatments for prostate cancer. In particular, we quantified the dosimetric impact of a treatment technique in which custom fabricated collimators were replaced with a multileaf collimator (MLC) and the custom range compensators (RC) were eliminated. The dosimetric impacts of these modifications were assessed for 10 patients with a commercial treatment planning system (TPS) and confirmed with corresponding Monte Carlo simulations. We assessed the impact on lifetime risks of radiogenic second cancers using detailed dose reconstructions and predictive dose-risk models based on epidemiologic data. We also performed illustrative calculations, using an isoeffect model, to examine the potential for hypofractionation. Specifically, we bracketed plausible intervals of proton fraction size and total treatment dose that were equivalent to a conventional photon treatment of 79.2 Gy in 44 fractions. Our results revealed that eliminating the RC and using an MLC had negligible effect on predicted dose distributions and second cancer risks. Even modest hypofractionation strategies can yield substantial cost savings. Together, our results suggest that it is feasible to modify the standard of care to increase treatment efficiency, reduce treatment costs to patients and insurers, while preserving high treatment quality

  17. Reduced Order Modeling for Non-equilibrium Radiation Hydrodynamics of Base Flow and Wakes: Enabling Manned Missions to Mars

    Data.gov (United States)

    National Aeronautics and Space Administration — Understanding non-equilibrium chemical kinetics and its interaction with radiation and fluid mechanics in hypersonic flows remains one of the largest obstacles to...

  18. Adjustment for smoking reduces radiation risk: fifth analysis of mortality of nuclear industry workers in Japan, 1999-2010

    Energy Technology Data Exchange (ETDEWEB)

    Kudo, S.; Ishida, J.; Yoshimoto, K.; Mizuno, S.; Ohshima, S.; Kasagi, F., E-mail: s_kudo@rea.or.jp [Instituto of Radiation Epidemiology, Radiation Effects Association, 1-9-16 Kajicho, Chiyoda-ku, 101-0044 Tokyo (Japan)

    2015-10-15

    Full text: Many cohort studies among nuclear industry workers have been carried out to determine the possible health effects of low-level radiation. In those studies, confounding factors, for example, age was adjusted to exclude the effect of difference of mortality by age to estimate radiation risk. But there are few studies adjusting for smoking that is known as a strong factor which affects mortality. Radiation Effects Association (Rea) initiated a cohort study of nuclear industry workers mortality in 1990. To examine non-radiation factors confounding on the mortality risk among the radiation workers, Rea have performed life-style questionnaire surveys among the part of workers at 1997 and 2003 and found the correlation between radiation dose and smoking rate. Mortality follow-up were made on 75,442 male respondents for an average of 8.3 years during the observation period 1999-2010. Estimates of Excess Relative Risk percent (Err %) per 10 mSv were obtained by using the Poisson regression. The Err for all causes was statistically significant (1.05 (90 % CI 0.31 : 1.80)), but no longer significant after adjusting for smoking (0.45 (-0.24 : 1.13)). The Err for all cancers excluding leukemia was not significant (0.92 (-0.30 : 2.16)), but after adjusting for smoking, it decreased (0.36 (-0.79 : 1.50)). Thus smoking has a large effect to obscure a radiation risk, so adjustment for smoking is important to estimate radiation risk. (Author)

  19. Adjustment for smoking reduces radiation risk: fifth analysis of mortality of nuclear industry workers in Japan, 1999-2010

    International Nuclear Information System (INIS)

    Kudo, S.; Ishida, J.; Yoshimoto, K.; Mizuno, S.; Ohshima, S.; Kasagi, F.

    2015-10-01

    Full text: Many cohort studies among nuclear industry workers have been carried out to determine the possible health effects of low-level radiation. In those studies, confounding factors, for example, age was adjusted to exclude the effect of difference of mortality by age to estimate radiation risk. But there are few studies adjusting for smoking that is known as a strong factor which affects mortality. Radiation Effects Association (Rea) initiated a cohort study of nuclear industry workers mortality in 1990. To examine non-radiation factors confounding on the mortality risk among the radiation workers, Rea have performed life-style questionnaire surveys among the part of workers at 1997 and 2003 and found the correlation between radiation dose and smoking rate. Mortality follow-up were made on 75,442 male respondents for an average of 8.3 years during the observation period 1999-2010. Estimates of Excess Relative Risk percent (Err %) per 10 mSv were obtained by using the Poisson regression. The Err for all causes was statistically significant (1.05 (90 % CI 0.31 : 1.80)), but no longer significant after adjusting for smoking (0.45 (-0.24 : 1.13)). The Err for all cancers excluding leukemia was not significant (0.92 (-0.30 : 2.16)), but after adjusting for smoking, it decreased (0.36 (-0.79 : 1.50)). Thus smoking has a large effect to obscure a radiation risk, so adjustment for smoking is important to estimate radiation risk. (Author)

  20. Effectiveness of Bismuth Shield to Reduce Eye Lens Radiation Dose Using the Photoluminescence Dosimetry in Computed Tomography

    International Nuclear Information System (INIS)

    Jung, Mi Young; Kweon, Dae Cheol; Kwon, Soo Il

    2009-01-01

    The purpose of our study was to determine the eye radiation dose when performing routine multi-detector computed tomography (MDCT). We also evaluated dose reduction and the effect on image quality of using a bismuth eye shield when performing head MDCT. Examinations were performed with a 64MDCT scanner. To compare the shielded/unshielded lens dose, the examination was performed with and without bismuth shielding in anthropomorphic phantom. To determine the average lens radiation dose, we imaged an anthropomorphic phantom into which calibrated photoluminescence glass dosimeter (PLD) were placed to measure the dose to lens. The phantom was imaged using the same protocol. Radiation doses to the lens with and without the lens shielding were measured and compared using the Student t test. In the qualitative evaluation of the MDCT scans, all were considered to be of diagnostic quality. We did not see any differences in quality between the shielded and unshielded brain. The mean radiation doses to the eye with the shield and to those without the shield were 21.54 versus 10.46 mGy, respectively. The lens shield enabled a 51.3% decrease in radiation dose to the lens. Bismuth in-plane shielding for routine eye and head MDCT decreased radiation dose to the lens without qualitative changes in image quality. The other radiosensitive superficial organs specifically must be protected with shielding.

  1. Outcomes and Patterns of Failure for Grade 2 Meningioma Treated With Reduced-Margin Intensity Modulated Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Press, Robert H. [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Prabhu, Roshan S., E-mail: roshansprabhu@gmail.com [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Appin, Christina L.; Brat, Daniel J. [Department of Pathology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Shu, Hui-Kuo G. [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Hadjipanayis, Constantinos; Olson, Jeffrey J.; Oyesiku, Nelson M. [Department of Neurosurgery, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States); Curran, Walter J.; Crocker, Ian [Department of Radiation Oncology, Emory University, Atlanta, Georgia (United States); Winship Cancer Institute, Emory University, Atlanta, Georgia (United States)

    2014-04-01

    Purpose: The purpose of this study was to evaluate intracranial control and patterns of local recurrence (LR) for grade 2 meningiomas treated with intensity modulated radiation therapy (IMRT) with limited total margin expansions of ≤1 cm. Methods and Materials: We reviewed records of patients with a neuropathological diagnosis of grade 2 meningioma who underwent IMRT at our institution between 2002 and 2012. Actuarial rates were determined by the Kaplan-Meier method from the end of RT. LR was defined as in-field if ≥90% of the recurrence was within the prescription isodose, out-of-field (marginal) if ≥90% was outside of the prescription isodose, and both if neither criterion was met. Results: Between 2002 and 2012, a total of 54 consecutive patients underwent IMRT for grade 2 meningioma. Eight of these patients had total initial margins >1 cm and were excluded, leaving 46 patients for analysis. The median imaging follow-up period was 26.2 months (range, 7-107 months). The median dose for fractionated IMRT was 59.4 Gy (range, 49.2-61.2 Gy). Median clinical target volume (CTV), planning target volume (PTV), and total margin expansion were 0.5 cm, 0.3 cm, and 0.8 cm, respectively. LR occurred in 8 patients (17%), with 2-year and 3-year actuarial local control (LC) of 92% and 74%, respectively. Six of 8 patients (85%) had a known pattern of failure. Five patients (83%) had in-field LR; no patients had marginal LR; and 1 patient (17%) had both. Conclusions: The use of IMRT to treat grade 2 meningiomas with total initial margins (CTV + PTV) ≤1 cm did not appear to compromise outcomes or increase marginal failures compared with other modern retrospective series. Of the 46 patients who had margins ≤1 cm, none experienced marginal failure only. These results demonstrate efficacy and low risk of marginal failure after IMRT treatment of grade 2 meningiomas with reduced margins, warranting study within a prospective clinical trial.

  2. Great Lakes Literacy Principles

    Science.gov (United States)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  3. The Next Great Generation?

    Science.gov (United States)

    Brownstein, Andrew

    2000-01-01

    Discusses ideas from a new book, "Millennials Rising: The Next Great Generation," (by Neil Howe and William Strauss) suggesting that youth culture is on the cusp of a radical shift with the generation beginning with this year's college freshmen who are typically team oriented, optimistic, and poised for greatness on a global scale. Includes a…

  4. Technical Report on the Development of Novel Technology for Reducing the Toxicity of Mistletoe Lectin by using Radiation Fusion Technology

    International Nuclear Information System (INIS)

    Lee, Ju Woon; Kim, Jae Hun; Choi, Jong Il; Song, Beom Seok; Yoon, Yo Han; Jung, Pil Mun; Sung, Nak Yun

    2009-10-01

    The aim of this study was conducted to investigate the effect of irradiation on detoxification, structural change, and physiological change of Mistletoe lectin. Optimal irradiation dose was determined from the result of having maximum detoxification and remaining the immunological activity Irradiation technology could be effective method for detoxification of Mistletoe lectin containing the immunological activity. The results indicate the feasibility of novel technology for reduction of the toxicity of Mistletoe lectin by using radiation technology. Practical state though clinical test is needed to extend biomedicine field using radiation technology and improve of public health by the control of the disease that gradually increase every year

  5. Feasibility of radiation preservation of potatoes and onions in Pakistan

    International Nuclear Information System (INIS)

    Khan, Ismail; Muhammad, Amir.

    1975-01-01

    The storage problem of potatoes and onions in Pakistan has been explained. The feasibility of preserving these vegetables by radiation and the cost and economics of the technology is examined. It has been concluded that radiation with subsequent storage at 15 0 -20 0 C will not only reduce the spoilage losses considerably but also give great benefit to the producer

  6. The feasibility of 10 keV X-ray as radiation source in total dose response radiation test

    International Nuclear Information System (INIS)

    Li Ruoyu; Li Bin; Luo Hongwei; Shi Qian

    2005-01-01

    The standard radiation source utilized in traditional total dose response radiation test is 60 Co, which is environment-threatening. X-rays, as a new radiation source, has the advantages such as safety, precise control of dose rate, strong intensity, possibility of wafer-level test or even on-line test, which greatly reduce cost for package, test and transportation. This paper discussed the feasibility of X-rays replacing 60 Co as the radiation source, based on the radiation mechanism and the effects of radiation on gate oxide. (authors)

  7. Method and means of reducing erosion of components of plasma devices exposed to helium and hydrogen isotope radiation

    International Nuclear Information System (INIS)

    Kaminsky, M.S.; Das, S.K.; Rossing, T.D.

    1977-01-01

    Surfaces of components of plasma devices exposed to radiation by atoms or ions of helium or isotopes of hydrogen can be protected from damage due to blistering by shielding the surfaces with a structure formed by sintering a powder of aluminum or beryllium and its oxide or by coating the surfaces with such a sintered metal powder. 7 claims

  8. Reducing radiation dose without compromising image quality in preoperative perforator flap imaging with CTA using ASIR technology.

    Science.gov (United States)

    Niumsawatt, Vachara; Debrotwir, Andrew N; Rozen, Warren Matthew

    2014-01-01

    Computed tomographic angiography (CTA) has become a mainstay in preoperative perforator flap planning in the modern era of reconstructive surgery. However, the increased use of CTA does raise the concern of radiation exposure to patients. Several techniques have been developed to decrease radiation dosage without compromising image quality, with varying results. The most recent advance is in the improvement of image reconstruction using an adaptive statistical iterative reconstruction (ASIR) algorithm. We sought to evaluate the image quality of ASIR in preoperative deep inferior epigastric perforator (DIEP) flap surgery, through a direct comparison with conventional filtered back projection (FBP) images. A prospective review of 60 consecutive ASIR and 60 consecutive FBP CTA images using similar protocol (except for radiation dosage) was undertaken, analyzed by 2 independent reviewers. In both groups, we were able to accurately identify axial arteries and their perforators. Subjective analysis of image quality demonstrated no statistically significant difference between techniques. ASIR can thus be used for preoperative imaging with similar image quality to FBP, but with a 60% reduction in radiation delivery to patients.

  9. Implementation of a competency check-off in diagnostic fluoroscopy for radiology trainees: impact on reducing radiation for three common fluoroscopic exams in children

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Sweta [University of Missouri-Kansas City SOM, Department of Radiology, Kansas City, MO (United States); Desouches, Stephane L. [University of Missouri-Kansas City SOM, Department of Radiology, Kansas City, MO (United States); St. Luke' s Hospital, Department of Radiology, Kansas City, MO (United States); Lowe, Lisa H.; Kasraie, Nima; Reading, Brenton [University of Missouri-Kansas City SOM, Department of Radiology, Kansas City, MO (United States); Children' s Mercy Hospitals and Clinics, Department of Radiology, Kansas City, MO (United States)

    2014-07-24

    Fluoroscopy is an important tool for diagnosis in the pediatric population, but it carries the risk of radiation exposure. Because radiology resident education and experience in the use of fluoroscopy equipment in children vary, we implemented an intervention to standardize fluoroscopy training. The purpose of this study is to determine the impact of implementing a fluoroscopy competency check-off for radiology resident trainees aimed at decreasing radiation exposure in three common pediatric fluoroscopic studies. A fluoroscopy competency check-off form was developed for radiology resident trainees performing pediatric procedures. Techniques used to limit radiation exposure for common pediatric radiologic studies were reviewed as part of the check-off process. Pediatric radiologists supervised each trainee until they demonstrated competence to independently perform three specified procedures. Radiation dose was recorded for the three procedures, upper GI (UGI), voiding cystourethrogram (VCUG) and oropharyngeal (OPM) exams, over 6 months preceding and 6 months following implementation of the competency check-off. The mean cumulative dose for each procedure was compared before and after implementation of competency check-off using a Kruskal-Wallis test. During the 12-month study period doses from 909 fluoroscopic procedures were recorded. In the 6 months preceding competency check-off implementation, procedures were performed by 24 radiology resident trainees including 171 UGI, 176 VCUG and 171 OPM exams. In the 6 months following competency check-off, 23 trainees performed 114 UGI, 145 VCUG and 132 OPM exams. After competency check-off implementation, a statistically significant reduction in average radiation dose was found for all three studies (P < 0.001). Median cumulative doses (mGy) were decreased by 33%, 36% and 13% for UGIs, VCUGs and OPMs, respectively. Implementation of a competency check-off for radiology resident trainees can reduce average radiation

  10. Implementation of a competency check-off in diagnostic fluoroscopy for radiology trainees: impact on reducing radiation for three common fluoroscopic exams in children

    International Nuclear Information System (INIS)

    Shah, Sweta; Desouches, Stephane L.; Lowe, Lisa H.; Kasraie, Nima; Reading, Brenton

    2015-01-01

    Fluoroscopy is an important tool for diagnosis in the pediatric population, but it carries the risk of radiation exposure. Because radiology resident education and experience in the use of fluoroscopy equipment in children vary, we implemented an intervention to standardize fluoroscopy training. The purpose of this study is to determine the impact of implementing a fluoroscopy competency check-off for radiology resident trainees aimed at decreasing radiation exposure in three common pediatric fluoroscopic studies. A fluoroscopy competency check-off form was developed for radiology resident trainees performing pediatric procedures. Techniques used to limit radiation exposure for common pediatric radiologic studies were reviewed as part of the check-off process. Pediatric radiologists supervised each trainee until they demonstrated competence to independently perform three specified procedures. Radiation dose was recorded for the three procedures, upper GI (UGI), voiding cystourethrogram (VCUG) and oropharyngeal (OPM) exams, over 6 months preceding and 6 months following implementation of the competency check-off. The mean cumulative dose for each procedure was compared before and after implementation of competency check-off using a Kruskal-Wallis test. During the 12-month study period doses from 909 fluoroscopic procedures were recorded. In the 6 months preceding competency check-off implementation, procedures were performed by 24 radiology resident trainees including 171 UGI, 176 VCUG and 171 OPM exams. In the 6 months following competency check-off, 23 trainees performed 114 UGI, 145 VCUG and 132 OPM exams. After competency check-off implementation, a statistically significant reduction in average radiation dose was found for all three studies (P < 0.001). Median cumulative doses (mGy) were decreased by 33%, 36% and 13% for UGIs, VCUGs and OPMs, respectively. Implementation of a competency check-off for radiology resident trainees can reduce average radiation

  11. Efficacy of the RADPAD Protection Drape in Reducing Operators' Radiation Exposure in the Catheterization Laboratory: A Sham-Controlled Randomized Trial.

    Science.gov (United States)

    Vlastra, Wieneke; Delewi, Ronak; Sjauw, Krischan D; Beijk, Marcel A; Claessen, Bimmer E; Streekstra, Geert J; Bekker, Robbert J; van Hattum, Juliette C; Wykrzykowska, Joanna J; Vis, Marije M; Koch, Karel T; de Winter, Robbert J; Piek, Jan J; Henriques, José P S

    2017-11-01

    Interventional cardiologists are increasingly exposed to radiation-induced diseases like cataract and the stochastic risk of left-sided brain tumors. The RADPAD is a sterile, disposable, lead-free shield placed on the patient with the aim to minimize operator-received scatter radiation. The objective of the trial was to examine the RADPAD's efficacy in a real-world situation. In the current, double-blind, sham-controlled, all-comer trial, patients undergoing diagnostic catheterization or percutaneous coronary interventions were randomized in a 1:1:1 ratio to a radiation absorbing shield (RADPAD), standard treatment (NOPAD), or a sham shield (SHAMPAD). The sham shield allowed testing for shield-induced radiation behavior. The primary outcome was the difference in relative exposure of the primary operator between the RADPAD and NOPAD arms and was defined as the ratio between operator's exposure (E in µSv) and patient exposure (dose area product in mGy·cm 2 ), measured per procedure. A total of 766 consecutive coronary procedures were randomized to the use of RADPAD (N=255), NOPAD (N=255), or SHAMPAD (N=256). The use of RADPAD was associated with a 20% reduction in relative operator exposure compared with that of NOPAD ( P =0.01) and a 44% relative exposure reduction compared with the use of a SHAMPAD ( P RADPAD radiation shield reduced operator radiation exposure compared with procedures with NOPAD or SHAMPAD. This study supports the routine use of RADPAD in the catheterization laboratory. URL: https://www.clinicaltrials.gov. Unique identifier: NCT03139968. © 2017 American Heart Association, Inc.

  12. Great Indoors Awards 2007

    Index Scriptorium Estoniae

    2007-01-01

    Hollandis Maastrichtis jagati 17. XI esimest korda rahvusvahelist auhinda The Great Indoors Award. Aasta sisekujundusfirmaks valiti Masamichi Katayama asutatud Wonderwall. Auhinna said veel Zaha Hadid, Heatherwick Studio, Ryui Nakamura Architects ja Item Idem

  13. Great Lakes Bathymetry

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bathymetry of Lakes Michigan, Erie, Saint Clair, Ontario and Huron has been compiled as a component of a NOAA project to rescue Great Lakes lake floor geological and...

  14. Noise reduction technology reduces radiation dose in chronic total occlusions percutaneous coronary intervention: a propensity score-matched analysis.

    Science.gov (United States)

    Maccagni, Davide; Benincasa, Susanna; Bellini, Barbara; Candilio, Luciano; Poletti, Enrico; Carlino, Mauro; Colombo, Antonio; Azzalini, Lorenzo

    2018-03-23

    Chronic total occlusions (CTO) percutaneous coronary intervention (PCI) is associated with high radiation dose. Our study aim was to evaluate the impact of the implementation of a noise reduction technology (NRT) on patient radiation dose during CTO PCI. A total of 187 CTO PCIs performed between February 2016 and May 2017 were analyzed according to the angiographic systems utilized: Standard (n = 60) versus NRT (n = 127). Propensity score matching (PSM) was performed to control for differences in baseline characteristics. Primary endpoints were Cumulative Air Kerma at Interventional Reference Point (AK at IRP), which correlates with patient's tissue reactions; and Kerma Area Product (KAP), a surrogate measure of patient's risk of stochastic radiation effects. An Efficiency Index (defined as fluoroscopy time/AK at IRP) was calculated for each procedure. Image quality was evaluated using a 5-grade Likert-like scale. After PSM, n = 55 pairs were identified. Baseline and angiographic characteristics were well matched between groups. Compared to the Standard system, NRT was associated with lower AK at IRP [2.38 (1.80-3.66) vs. 3.24 (2.04-5.09) Gy, p = 0.035], a trend towards reduction for KAP [161 (93-244) vs. 203 (136-363) Gycm 2 , p = 0.069], and a better Efficiency Index [16.75 (12.73-26.27) vs. 13.58 (9.92-17.63) min/Gy, p = 0.003]. Image quality was similar between the two groups (4.39 ± 0.53 Standard vs. 4.34 ± 0.47 NRT, p = 0.571). In conclusion, compared with a Standard system, the use of NRT in CTO PCI is associated with lower patient radiation dose and similar image quality.

  15. Health physics manual of good practices for reducing radiation exposure to levels that are as low as reasonably achievable (ALARA)

    International Nuclear Information System (INIS)

    Herrington, W.N.; Higby, D.P.; Kathren, R.L.; Merwin, S.E.; Stoetzel, G.A.

    1988-06-01

    A primary objective of the US Department of Energy (DOE) health physics and radiation protection program has been to limit radiation exposures to those levels that are as low as reasonably achievable (ALARA). As a result, the ALARA concept developed into a program and a set of operational principles to ensure that the objective was consistently met. Implementation of these principles required that a guide be produced. The original ALARA guide was issued by DOE in 1980 to promote improved understanding of ALARA concepts within the DOE community and to assist those responsible for operational ALARA activities in attaining their goals. Since 1980, additional guidance has been published by national and international organizations to provide further definition and clarification to ALARA concepts. As basic ALARA experience increased, the value and role of the original guide prompted the DOE Office of Nuclear Safety (ONS) to support a current revision. The revised manual of good practices includes six sections: 1.0 Introduction, 2.0 Administration, 3.0 Optimization, 4.0 Setting and Evaluating ALARA Goals, 5.0 Radiological Design, and 6.0 Conduct of Operations. The manual is directed primarily to contractor and DOE staff who are responsible for conduct and overview of radiation protection and ALARA programs at DOE facilities. The intent is to provide sufficient guidance such that the manual, if followed, will ensure that radiation exposures are maintained as low as reasonably achievable and will establish the basis for a formally structured and auditable program. 118 refs., 16 figs., 3 tabs

  16. Intraarticular Sacroiliac Joint Injection Under Computed Tomography Fluoroscopic Guidance: A Technical Note to Reduce Procedural Time and Radiation Dose

    International Nuclear Information System (INIS)

    Paik, Nam Chull

    2016-01-01

    PurposeA technique for computed tomography fluoroscopy (CTF)-guided intraarticular (IA) sacroiliac joint (SIJ) injection was devised to limit procedural time and radiation dose.MethodsOur Institutional Review Board approved this retrospective analysis and waived the requirement for informed consent. Overall, 36 consecutive diagnostic or therapeutic IA SIJ injections (unilateral, 20; bilateral, 16) performed in 34 patients (female, 18; male, 16) with a mean age of 45.5 years (range 20–76 years) under CTF guidance were analyzed, assessing technical success (i.e., IA contrast spread), procedural time, and radiation dose.ResultsAll injections were successful from a technical perspective and were free of serious complications. Respective median procedural times and effective doses of SIJ injection were as follows: unilateral, 5.28 min (range 3.58–8.00 min) and 0.11 millisievert (mSv; range 0.07–0.24 mSv); and bilateral, 6.72 min (range 4.17–21.17 min) and 0.11 mSv (range 0.09–0.51 mSv).ConclusionsGiven the high rate of technical success achieved in limited time duration and with little radiation exposure, CTF-guided IA SIJ injection is a practical and low-risk procedure.

  17. Bacterial ice nuclei impact cloud lifetime and radiative properties and reduce atmospheric heat loss in the BRAMS simulation model

    International Nuclear Information System (INIS)

    Costa, Tassio S; Gonçalves, Fábio L T; Yamasoe, Marcia A; Martins, Jorge A; Morris, Cindy E

    2014-01-01

    This study examines the effect of the bacterial species Pseudomonas syringae acting as ice nuclei (IN) on cloud properties to understand its impact on local radiative budget and heating rates. These bacteria may become active IN at temperatures as warm as −2 °C. Numerical simulations were developed using the Brazilian Regional Atmospheric Model System (BRAMS). To investigate the isolated effect of bacterial IN, four scenarios were created considering only homogeneous and bacterial ice nucleation, with 1, 10 and 100 IN per cubic meter of cloud volume and one with no bacteria. Moreover, two other scenarios were generated: the BRAMS default parameterization and its combination with bacterial IN. The model reproduced a strong convective cell over São Paulo on 3 March 2003. Results showed that bacterial IN may change cloud evolution as well as its microphysical properties, which in turn influence cloud radiative properties. For example, the reflected shortwave irradiance over an averaged domain in a scenario considering bacterial IN added to the BRAMS default parameterization was 14% lower than if bacteria were not considered. Heating rates can also be impacted, especially due to differences in cloud lifetime. Results suggest that the omission of bacterial IN in numerical models, including global cloud models, could neglect relevant ice nucleation processes that potentially influence cloud radiative properties. (letter)

  18. Intraarticular Sacroiliac Joint Injection Under Computed Tomography Fluoroscopic Guidance: A Technical Note to Reduce Procedural Time and Radiation Dose

    Energy Technology Data Exchange (ETDEWEB)

    Paik, Nam Chull, E-mail: pncspine@gmail.com [Arumdaun Wooldul Spine Hospital, Department of Radiology (Korea, Republic of)

    2016-07-15

    PurposeA technique for computed tomography fluoroscopy (CTF)-guided intraarticular (IA) sacroiliac joint (SIJ) injection was devised to limit procedural time and radiation dose.MethodsOur Institutional Review Board approved this retrospective analysis and waived the requirement for informed consent. Overall, 36 consecutive diagnostic or therapeutic IA SIJ injections (unilateral, 20; bilateral, 16) performed in 34 patients (female, 18; male, 16) with a mean age of 45.5 years (range 20–76 years) under CTF guidance were analyzed, assessing technical success (i.e., IA contrast spread), procedural time, and radiation dose.ResultsAll injections were successful from a technical perspective and were free of serious complications. Respective median procedural times and effective doses of SIJ injection were as follows: unilateral, 5.28 min (range 3.58–8.00 min) and 0.11 millisievert (mSv; range 0.07–0.24 mSv); and bilateral, 6.72 min (range 4.17–21.17 min) and 0.11 mSv (range 0.09–0.51 mSv).ConclusionsGiven the high rate of technical success achieved in limited time duration and with little radiation exposure, CTF-guided IA SIJ injection is a practical and low-risk procedure.

  19. Impact of reduced-radiation dual-energy protocols using 320-detector row computed tomography for analyzing urinary calculus components: initial in vitro evaluation.

    Science.gov (United States)

    Cai, Xiangran; Zhou, Qingchun; Yu, Juan; Xian, Zhaohui; Feng, Youzhen; Yang, Wencai; Mo, Xukai

    2014-10-01

    To evaluate the impact of reduced-radiation dual-energy (DE) protocols using 320-detector row computed tomography on the differentiation of urinary calculus components. A total of 58 urinary calculi were placed into the same phantom and underwent DE scanning with 320-detector row computed tomography. Each calculus was scanned 4 times with the DE protocols using 135 kV and 80 kV tube voltage and different tube current combinations, including 100 mA and 570 mA (group A), 50 mA and 290 mA (group B), 30 mA and 170 mA (group C), and 10 mA and 60 mA (group D). The acquisition data of all 4 groups were then analyzed by stone DE analysis software, and the results were compared with x-ray diffraction analysis. Noise, contrast-to-noise ratio, and radiation dose were compared. Calculi were correctly identified in 56 of 58 stones (96.6%) using group A and B protocols. However, only 35 stones (60.3%) and 16 stones (27.6%) were correctly diagnosed using group C and D protocols, respectively. Mean noise increased significantly and mean contrast-to-noise ratio decreased significantly from groups A to D (P calculus component analysis while reducing patient radiation exposure to 1.81 mSv. Further reduction of tube currents may compromise diagnostic accuracy. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Development and demonstration of surveillance and diagnostics of rotating machinery for reducing radiation exposure to nuclear power plant personnel: Final report

    International Nuclear Information System (INIS)

    Allen, J.W.; Bohanick, J.S.

    1988-01-01

    This program was designed to reduce radiation exposure to power plant personnel resulting from inspection, maintenance, and repair of rotating equipment. The new rotating machinery monitoring system for this program was installed at GGNS during August 1983. This document provides a functional description of the hardware and software that comprise the system and discusses the application of the monitoring system to achieving overall program goals. The analyses of the monitored rotating machinery during the plant startup phase and after the plant's first fuel cycle are presented in addition to the radiation dose reduction which occurred as a direct and indirect result of the RMSS. The dose reduction program at GGNS is reviewed and recommendations made to incorporate this program with the RMSS. 28 refs., 64 figs., 43 tabs

  1. Ambient ultraviolet radiation in the Arctic reduces root biomass and alters microbial community composition but has no effects on microbial biomass

    DEFF Research Database (Denmark)

    Rinnan, R.; Keinänen, M.M.; Kasurinen, A.

    2005-01-01

    We assessed the effects of ambient solar ultraviolet (UV) radiation on below-ground parameters in an arctic heath in north-eastern Greenland. We hypothesized that the current UV fluxes would reduce root biomass and mycorrhizal colonization and that these changes would lead to lower soil microbial...... biomass and altered microbial community composition. These hypotheses were tested on cored soil samples from a UV reduction experiment with three filter treatments (Mylar, 60% UV-B reduction; Lexan, up to 90% UV-B reduction+UV-A reduction; UV transparent Teflon, filter control) and an open control...... treatment in two study sites after 3 years' manipulation. Reduction of both UV-A and UV-B radiation caused over 30% increase in the root biomass of Vaccinium uliginosum, which was the dominant plant species. UV reduction had contrasting effects on ericoid mycorrhizal colonization of V. uliginosum roots...

  2. Interactive effects of UV radiation and reduced precipitation on the seasonal leaf phenolic content/composition and the antioxidant activity of naturally growing Arbutus unedo plants.

    Science.gov (United States)

    Nenadis, Nikolaos; Llorens, Laura; Koufogianni, Agathi; Díaz, Laura; Font, Joan; Gonzalez, Josep Abel; Verdaguer, Dolors

    2015-12-01

    The effects of UV radiation and rainfall reduction on the seasonal leaf phenolic content/composition and antioxidant activity of the Mediterranean shrub Arbutus unedo were studied. Naturally growing plants of A. unedo were submitted to 97% UV-B reduction (UVA), 95% UV-A+UV-B reduction (UV0) or near-ambient UV levels (UVBA) under two precipitation regimes (natural rainfall or 10-30% rainfall reduction). Total phenol, flavonol and flavanol contents, levels of eight phenols and antioxidant activity [DPPH(●) radical scavenging and Cu (II) reducing capacity] were measured in sun-exposed leaves at the end of four consecutive seasons. Results showed a significant seasonal variation in the leaf content of phenols of A. unedo, with the lowest values found in spring and the highest in autumn and/or winter. Leaf ontogenetic development and/or a possible effect of low temperatures in autumn/winter may account for such findings. Regardless of the watering regime and the sampling date, plant exposure to UV-B radiation decreased the total flavanol content of leaves, while it increased the leaf content in quercitrin (the most abundant quercetin derivative identified). By contrast, UV-A radiation increased the leaf content of theogallin, a gallic acid derivative. Other phenolic compounds (two quercetin derivatives, one of them being avicularin, and one kaempferol derivative, juglanin), as well as the antioxidant activity of the leaves, showed different responses to UV radiation depending on the precipitation regime. Surprisingly, reduced rainfall significantly decreased the total amount of quantified quercetin derivatives as well as the DPPH scavenging activity in A. unedo leaves. To conclude, present findings indicate that leaves of A. unedo can be a good source of antioxidants throughout the year, but especially in autumn and winter. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Efficacy of Synbiotics to Reduce Acute Radiation Proctitis Symptoms and Improve Quality of Life: A Randomized, Double-Blind, Placebo-Controlled Pilot Trial

    International Nuclear Information System (INIS)

    Nascimento, Mariana; Aguilar-Nascimento, José Eduardo; Caporossi, Cervantes; Castro-Barcellos, Heloisa Michelon; Motta, Rodrigo Teixeira

    2014-01-01

    Purpose: To evaluate whether the daily intake of synbiotics interferes in radiation-induced acute proctitis symptoms and in quality of life in patients with prostate cancer. Methods and Materials: Twenty patients who underwent 3-dimensional conformal radiation therapy for prostate cancer were randomized to intake either a synbiotic powder containing Lactobacillus reuteri 10 8  colony-forming units and 4.3 g of soluble fiber (Nestlé) or placebo. The questionnaire EORTC QLQ-PRT23 was applied before the beginning of radiation therapy and in every week for the first 4 weeks of treatment. The sum of both the complete (proctitis symptoms plus quality of life) and partial (proctitis symptoms) scores of the EORTC QLQ-PRT23 (European Organization for Research and Treatment of Cancer Quality of Life Module for Proctitis–23 items) questionnaire were the main endpoints. Results: This pilot study showed that the complete questionnaire score (median [range]) was higher in the second (23 [21-30] vs 26.5 [22-34], P<.05) and third (23 [21-32] vs 27.5 [24-33], P<.01) weeks in the placebo group. Proctitis symptoms were highest scored in the placebo group in both the second (19.5 [16-25]) and third (19 [17-24]) weeks than in the synbiotic group (week 2: 16.5 [15-20], P<.05; week 3: 17 [15-23], P<.01). In both scores the placebo group had a significantly higher result (P<.01) than the synbiotic group (repeated-measures analysis of variance). Conclusions: Synbiotics reduce proctitis symptoms and improve quality of life in radiation-induced acute proctitis during radiation therapy for prostate cancer

  4. Efficacy of Synbiotics to Reduce Acute Radiation Proctitis Symptoms and Improve Quality of Life: A Randomized, Double-Blind, Placebo-Controlled Pilot Trial

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Mariana, E-mail: mari1980hemato@yahoo.com.br [Department of Medicine, University Center of Varzea Grande (UNIVAG), Varzea Grande, Mato Grosso (Brazil); Aguilar-Nascimento, José Eduardo [Department of Medicine, University Center of Varzea Grande (UNIVAG), Varzea Grande, Mato Grosso (Brazil); Caporossi, Cervantes; Castro-Barcellos, Heloisa Michelon; Motta, Rodrigo Teixeira [Department of Medicine, Federal University of Mato Grosso (UFMT), Cuiabá, Mato Grosso (Brazil)

    2014-10-01

    Purpose: To evaluate whether the daily intake of synbiotics interferes in radiation-induced acute proctitis symptoms and in quality of life in patients with prostate cancer. Methods and Materials: Twenty patients who underwent 3-dimensional conformal radiation therapy for prostate cancer were randomized to intake either a synbiotic powder containing Lactobacillus reuteri 10{sup 8} colony-forming units and 4.3 g of soluble fiber (Nestlé) or placebo. The questionnaire EORTC QLQ-PRT23 was applied before the beginning of radiation therapy and in every week for the first 4 weeks of treatment. The sum of both the complete (proctitis symptoms plus quality of life) and partial (proctitis symptoms) scores of the EORTC QLQ-PRT23 (European Organization for Research and Treatment of Cancer Quality of Life Module for Proctitis–23 items) questionnaire were the main endpoints. Results: This pilot study showed that the complete questionnaire score (median [range]) was higher in the second (23 [21-30] vs 26.5 [22-34], P<.05) and third (23 [21-32] vs 27.5 [24-33], P<.01) weeks in the placebo group. Proctitis symptoms were highest scored in the placebo group in both the second (19.5 [16-25]) and third (19 [17-24]) weeks than in the synbiotic group (week 2: 16.5 [15-20], P<.05; week 3: 17 [15-23], P<.01). In both scores the placebo group had a significantly higher result (P<.01) than the synbiotic group (repeated-measures analysis of variance). Conclusions: Synbiotics reduce proctitis symptoms and improve quality of life in radiation-induced acute proctitis during radiation therapy for prostate cancer.

  5. The GREAT3 challenge

    International Nuclear Information System (INIS)

    Miyatake, H; Mandelbaum, R; Rowe, B

    2014-01-01

    The GRavitational lEnsing Accuracy Testing 3 (GREAT3) challenge is an image analysis competition that aims to test algorithms to measure weak gravitational lensing from astronomical images. The challenge started in October 2013 and ends 30 April 2014. The challenge focuses on testing the impact on weak lensing measurements of realistically complex galaxy morphologies, realistic point spread function, and combination of multiple different exposures. It includes simulated ground- and space-based data. The details of the challenge are described in [1], and the challenge website and its leader board can be found at http://great3challenge.info and http://great3.projects.phys.ucl.ac.uk/leaderboard/, respectively

  6. Selective brain lesions reduce morphine- and radiation-induced locomotor hyperactivity of the C57BL/6J mouse

    International Nuclear Information System (INIS)

    Mickley, G.A.; Stevens, K.E.; White, G.A.; Gibbs, G.L.

    1984-01-01

    The apparent resemblance between the stereotypic locomotor hyperactivity observed after either an injection of morphine or irradiation of the C57BL/6J mouse has suggested the possibility of similar biochemical and neuroanatomical substrates of these behaviors. In this study the authors made selective brain lesions in an attempt to reverse the locomotor response observed after morphine (30 mg/kg) or radiation (1500 rads /sup 60/Co) treatments. Lesions impinging on both the dorso-medial caudate and lateral septal nuclei caused a significant decrease in morphine-induced and radiogenic locomotion. Lesions of the individual brain areas did not significantly alter the opiate locomotor response. This reduction in locomotion could not be attributed to a generalized post-surgical lethargy since other brain lesions of similar size did not significantly suppress these behaviors. These data suggest the possibility of some common central nervous system mechanisms which may support the stereotypic locomotor hyperactivity observed in the C57BL/6J mouse after either morphine or radiation treatment

  7. Reduced repair of potentially lethal radiation damage in glutathione synthetase-deficient human fibroblasts after X-irradiation

    International Nuclear Information System (INIS)

    Midander, J.; Revesz, L.; Deschavanne, P.J.; Debieu, D.; Malaise, E.P.

    1986-01-01

    Using a human fibroblast strain deficient in glutathione synthetase and a related proficient control strain, the role of glutathione (GSH) in repair of potentially lethal damage (PLD) has been investigated in determining survival by plating cells immediately or 24 h after irradiation. After oxic or hypoxic irradiation, both cell strains repair radiation-induced damage. However, under hypoxic conditions, the proficient cells repair PLD as well as under oxic conditions while the deficient cells repair less PLD after irradiation under hypoxic than under oxic conditions. Therefore, the oxygen enhancement ratio (o.e.r.) for proficient cells is similar whether the cells are plated immediately or 24 h later (2.0 and 2.13, respectively). In contrast, the o.e.r. for deficient cells is lower when the cells are plated 24 h after irradiation than when they are plated immediately thereafter (1.16 as compared to 1.55). The results indicate that GSH is involved in PLD repair and, in particular, in the repair of damage induced by radiation delivered under hypoxic conditions. (author)

  8. Nothing Great Is Easy

    OpenAIRE

    Stansbie, Lisa

    2014-01-01

    A solo exhibition of 13 pieces of art work.\\ud \\ud Nothing Great is Easy is an exhibition of sculpture, film, drawing and photography that proposes reconstructed narratives using the sport of swimming and in particular the collective interaction and identity of the channel swimmer. The work utilises the processes, rituals/rules, language and the apparatus of sport.\\ud \\ud “Nothing great is easy” are the words on the memorial to Captain Matthew Webb who was the first man to swim the English ch...

  9. Reducing the radiation dose to the eye lens region during CT brain examination: the potential beneficial effect of the combined use of bolus and a bismuth shield

    International Nuclear Information System (INIS)

    Lai, C.W.K.; Chan, T.P.; Cheung, H.Y.; Wong, T.H.

    2015-01-01

    Objective: Computed Tomography (CT) is the leading contributor to medical exposure to ionizing radiation. Although the use of CT brain scans for patients with head injuries and convulsions has shown a tremendous growth, it has raised substantial concerns in the general public because of the risk of radiation-induced cataracts: the current available strategies to reduce the radiation dose to the eye lens region are limited. Therefore, the present research project was initiated with the aim of evaluating the potential benefit of the combined use of bolus and a bismuth shield on reducing the radiation dose to the eye lens region during CT brain examination. Materials and methods: We conducted a series of phantom studies to measure the entrance surface dose (ESD) that is delivered to the eye lens region during CT brain examination under the effect of different scanning and shielding setups. Results: Our results indicated, during CT brain examination: (1) a drastic reduction of 92.5% in the ESD to the eye lens region was found when the CT gantry was tilted from 0 deg. (overall ESD = 30.7 mGy) to 30 deg. cranially (overall ESD = 2.4 mGy), and (2) when the CT gantry was positioned at 0 deg. (the common practice in the clinical setting), the setups with the application of a) a bismuth shield, b) a bismuth shield with a face shield (air gap), c) a bismuth shield with bolus, and d) a bismuth shield with bolus and an air gap can result in an acceptable level of image quality with a smaller overall ESD delivered to the eye lens region (overall ESD = 23.2 mGy, 24 mGy, 21 mGy and 19.9 mGy, respectively) than the setup without the bismuth shield applied (overall ESD = 30.7 mGy). Conclusion: When the primary beam scanning through the eye lens region is unavoidable during CT brain examination, the combined use of a bismuth shield with bolus and a face shield is an easy-to-use and inexpensive shielding setup to reduce the radiation dose delivered to the eye lens region while

  10. Do Angiotensin-Converting Enzyme Inhibitors Reduce the Risk of Symptomatic Radiation Pneumonitis in Patients With Non-Small Cell Lung Cancer After Definitive Radiation Therapy? Analysis of a Single-Institution Database

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongmei [Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, P.R. of China (China); Liao, Zhongxing, E-mail: zliao@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhuang, Yan; Xu, Ting; Nguyen, Quynh-Nhu; Levy, Lawrence B.; O' Reilly, Michael [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gold, Kathryn A. [Department of Thoracic Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gomez, Daniel R. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-12-01

    Purpose: Preclinical studies have suggested that angiotensin-converting enzyme inhibitors (ACEIs) can mitigate radiation-induced lung injury. We sought here to investigate possible associations between ACEI use and the risk of symptomatic radiation pneumonitis (RP) among patients undergoing radiation therapy (RT) for non–small cell lung cancer (NSCLC). Methods and Materials: We retrospectively identified patients who received definitive radiation therapy for stages I to III NSCLC between 2004 and 2010 at a single tertiary cancer center. Patients must have received a radiation dose of at least 60 Gy for a single primary lung tumor and have had imaging and dosimetric data available for analysis. RP was quantified according to Common Terminology Criteria for Adverse Events, version 3.0. A Cox proportional hazard model was used to assess potential associations between ACEI use and risk of symptomatic RP. Results: Of 413 patients analyzed, 65 were using ACEIs during RT. In univariate analysis, the rate of RP grade ≥2 seemed lower in ACEI users than in nonusers (34% vs 46%), but this apparent difference was not statistically significant (P=.06). In multivariate analysis of all patients, ACEI use was not associated with the risk of symptomatic RP (hazard ratio [HR] = 0.66; P=.07) after adjustment for sex, smoking status, mean lung dose (MLD), and concurrent carboplatin and paclitaxel chemotherapy. Subgroup analysis showed that ACEI use did have a protective effect from RP grade ≥2 among patients who received a low (≤20-Gy) MLD (P<.01) or were male (P=.04). Conclusions: A trend toward reduction in symptomatic RP among patients taking ACEIs during RT for NSCLC was not statistically significant on univariate or multivariate analyses, although certain subgroups may benefit from use (ie, male patients and those receiving low MLD). The evidence at this point is insufficient to establish whether the use of ACEIs does or does not reduce the risk of RP.

  11. The Great Mathematician Project

    Science.gov (United States)

    Goldberg, Sabrina R.

    2013-01-01

    The Great Mathematician Project (GMP) introduces both mathematically sophisticated and struggling students to the history of mathematics. The rationale for the GMP is twofold: first, mathematics is a uniquely people-centered discipline that is used to make sense of the world; and second, students often express curiosity about the history of…

  12. Chemical chaperones reduce ionizing radiation-induced endoplasmic reticulum stress and cell death in IEC-6 cells

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Sang; Lee, Hae-June; Lee, Yoon-Jin [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Jeong, Jae-Hoon [Division of Radiotherapy, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Kang, Seongman [Division of Life Sciences, Korea University, Seoul 136-701 (Korea, Republic of); Lim, Young-Bin, E-mail: yblim@kirams.re.kr [Division of Radiation Effects, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)

    2014-07-25

    Highlights: • UPR activation precedes caspase activation in irradiated IEC-6 cells. • Chemical ER stress inducers radiosensitize IEC-6 cells. • siRNAs that targeted ER stress responses ameliorate IR-induced cell death. • Chemical chaperons prevent cell death in irradiated IEC-6 cells. - Abstract: Radiotherapy, which is one of the most effective approaches to the treatment of various cancers, plays an important role in malignant cell eradication in the pelvic area and abdomen. However, it also generates some degree of intestinal injury. Apoptosis in the intestinal epithelium is the primary pathological factor that initiates radiation-induced intestinal injury, but the mechanism by which ionizing radiation (IR) induces apoptosis in the intestinal epithelium is not clearly understood. Recently, IR has been shown to induce endoplasmic reticulum (ER) stress, thereby activating the unfolded protein response (UPR) signaling pathway in intestinal epithelial cells. However, the consequences of the IR-induced activation of the UPR signaling pathway on radiosensitivity in intestinal epithelial cells remain to be determined. In this study, we investigated the role of ER stress responses in IR-induced intestinal epithelial cell death. We show that chemical ER stress inducers, such as tunicamycin or thapsigargin, enhanced IR-induced caspase 3 activation and DNA fragmentation in intestinal epithelial cells. Knockdown of Xbp1 or Atf6 with small interfering RNA inhibited IR-induced caspase 3 activation. Treatment with chemical chaperones prevented ER stress and subsequent apoptosis in IR-exposed intestinal epithelial cells. Our results suggest a pro-apoptotic role of ER stress in IR-exposed intestinal epithelial cells. Furthermore, inhibiting ER stress may be an effective strategy to prevent IR-induced intestinal injury.

  13. Reducing the uncertainty in background marine aerosol radiative properties using CAM5 model results and CALIPSO-retrievals

    Science.gov (United States)

    Meskhidze, N.; Gantt, B.; Dawson, K.; Johnson, M. S.; Gasso, S.

    2012-12-01

    Abundance of natural aerosols in the atmosphere strongly affects global aerosol optical depth (AOD) and influences clouds and the hydrological cycle through its ability to act as cloud condensation nuclei (CCN). Because the anthropogenic contribution to climate forcing represents the difference between the total forcing and that from natural aerosols, understanding background aerosols is necessary to evaluate the influences of anthropogenic aerosols on cloud reflectivity and persistence (so-called indirect radiative forcing). The effects of marine aerosols are explored using remotely sensed data obtained by Cloud-aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and the NCAR Community Atmosphere Model (CAM5.0), coupled with the PNNL Modal Aerosol Model. CALIPSO-provided high resolution vertical profile information about different aerosol subtypes (defined as clean continental, marine, desert dust, polluted continental, polluted dust, and biomass burning), particulate depolarization ratio (or particle non-sphericity), reported aerosol color ratio (the ratio of aerosol backscatter at the two wavelengths) and lidar ratios over different parts of the oceans are compared to model-simulations to help evaluate the contribution of biogenic aerosol to CCN budget in the marine boundary layer. Model-simulations show that over biologically productive ocean waters primary organic aerosols of marine origin can contribute up to a 20% increase in CCN (at a supersaturation of 0.2%) number concentrations. Corresponding changes associated with cloud properties (liquid water path and droplet number) can decrease global annual mean indirect radiative forcing of anthropogenic aerosol (less cooling) by ~0.1 Wm-2 (7%). This study suggests ignoring the complex chemical composition and size distribution of sea spray particles could result in considerable uncertainties in predicted anthropogenic aerosol indirect effect.

  14. What great managers do.

    Science.gov (United States)

    Buckingham, Marcus

    2005-03-01

    Much has been written about the qualities that make a great manager, but most of the literature overlooks a fundamental question: What does a great manager actually do? While there are countless management styles, one thing underpins the behavior of all great managers. Above all, an exceptional manager comes to know and value the particular quirks and abilities of her employees. She figures out how to capitalize on her staffers' strengths and tweaks her environment to meet her larger goals. Such a specialized approach may seem like a lot of work. But in fact, capitalizing on each person's uniqueness can save time. Rather than encourage employees to conform to strict job descriptions that may include tasks they don't enjoy and aren't good at, a manager who develops positions for his staff members based on their unique abilities will be rewarded with behaviors that are far more efficient and effective than they would be otherwise. This focus on individuals also makes employees more accountable. Because staffers are evaluated on their particular strengths and weaknesses, they are challenged to take responsibility for their abilities and to hone them. Capitalizing on a person's uniqueness also builds a stronger sense of team. By taking the time to understand what makes each employee tick, a great manager shows that he sees his people for who they are. This personal investment not only motivates individuals but also galvanizes the entire team. Finally, this approach shakes up existing hierarchies, which leads to more creative thinking. To take great managing from theory to practice, the author says, you must know three things about a person: her strengths, the triggers that activate those strengths, and how she learns. By asking the right questions, squeezing the right triggers, and becoming aware of your employees' learning styles, you will discover what motivates each person to excel.

  15. Combination of ray-tracing and the method of moments for electromagnetic radiation analysis using reduced meshes

    Science.gov (United States)

    Delgado, Carlos; Cátedra, Manuel Felipe

    2018-05-01

    This work presents a technique that allows a very noticeable relaxation of the computational requirements for full-wave electromagnetic simulations based on the Method of Moments. A ray-tracing analysis of the geometry is performed in order to extract the critical points with significant contributions. These points are then used to generate a reduced mesh, considering the regions of the geometry that surround each critical point and taking into account the electrical path followed from the source. The electromagnetic analysis of the reduced mesh produces very accurate results, requiring a fraction of the resources that the conventional analysis would utilize.

  16. An economic evaluation of the use of rare-earth screens to reduce the radiation dose from diagnostic x-ray procedures in Israel

    International Nuclear Information System (INIS)

    Ginzburg, G.M.; Schlesinger, T.; Ben-Shlomo, A.

    1996-01-01

    In contrasts, reducing the patient dose by using improved radiology equipment will often result in a constant reduction without further managerial effort for the lifetime of the equipment. Changing equipment is administratively far easier than altering long-established work practices. There are several methods available to achieve dose reduction in diagnostic radiology via this second category. For example, dose reductions of between 10% and 20% can be achieved independently by reducing attenuation between patient and image receptor to a minimum by means of carbon fiber components in couch tops, cassette fronts and anti-scatter grids [13-15]. Radiation dosage in film radiography can be reduced by approximately 50% by the use of rare- earth screens, which enable a faster film speed to be utilized (thus reducing exposure time) without significant loss in the diagnostic quality of the image. Rare-earth screens have been found in England to be the most cost-effective method of reducing dosage in film radiography, providing large dose reductions at considerably lower costs than carbon fiber components (authors)

  17. An economic evaluation of the use of rare-earth screens to reduce the radiation dose from diagnostic x-ray procedures in Israel

    Energy Technology Data Exchange (ETDEWEB)

    Ginzburg, G M [Ministry of Health, Tel Aviv (Israel); Schlesinger, T; Ben-Shlomo, A [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center

    1996-12-01

    In contrasts, reducing the patient dose by using improved radiology equipment will often result in a constant reduction without further managerial effort for the lifetime of the equipment. Changing equipment is administratively far easier than altering long-established work practices. There are several methods available to achieve dose reduction in diagnostic radiology via this second category. For example, dose reductions of between 10% and 20% can be achieved independently by reducing attenuation between patient and image receptor to a minimum by means of carbon fiber components in couch tops, cassette fronts and anti-scatter grids [13-15]. Radiation dosage in film radiography can be reduced by approximately 50% by the use of rare- earth screens, which enable a faster film speed to be utilized (thus reducing exposure time) without significant loss in the diagnostic quality of the image. Rare-earth screens have been found in England to be the most cost-effective method of reducing dosage in film radiography, providing large dose reductions at considerably lower costs than carbon fiber components (authors).

  18. Functional inhibition of Ubiquitin conjugating Enzyme (UBE2C) reduces proliferation and sensitizes cervical and breast cancer cells to radiation, doxorubicin, tamoxifen and letrozole

    International Nuclear Information System (INIS)

    Bose, Mayil Vahanan; Rawat, Akhilesh; Gopisetty, Gopal; Thangarajan, Rajkumar; Ganesharaja, Selvaluxmy

    2014-01-01

    Cervical cancer is the second most common cancer in women, worldwide. About 80% of cervical cancer cases occur in developing countries. Breast cancer has overtaken cervical cancer in most of the urban centers in India. In recent years, interest in the role of Ubiquitin conjugating Enzyme E2C (UBE2C) in cancer has shown a dramatic increase. Several studies have reported UBE2C as a potential oncogene and therapeutic target. The objective of the study was to elucidate radiation and chemo-sensitivity in response to functional inhibition of UBE2C in cervical and breast cancer cell lines. Taqman Real time PCR was performed to measure UBE2C levels in cervical and breast cancer cell lines. A dominant negative form of UBE2C (DN-UBE2C) was used to functionally inhibit wild type UBE2C. Cell proliferation and anchorage independent growth were measured by colorimetric assay and soft agar assay respectively. Radiation and chemo response of cell lines were assessed by colorimetric assay and clonogenic assay. Difference in sensitivity to radiation was observed among the cervical cancer cell lines studied. The growth rate of SiHa and HeLa transfected with DN- UBE2C was significantly reduced compared to vector control. Further, DN-UBE2C mediated radio-sensitivity was correlated with a significant decrease in resistance to radiation by SiHa and HeLa cells after transfection when compared to control cultures. Similarly, both the growth rate and the anchorage independent growth of MCF7 and MDAMB231 cells transfected with DN-UBE2C were significantly reduced compared to cells transfected with vector alone. MCF7 and MDAMB231 cells expressing DN-UBE2C were significantly more sensitive to different doses of radiation and doxorubicin compared to controls. In addition, DN-UBE2C transfected MCF7 cells were more sensitive to inhibition by tamoxifen and letrozole compared to vector controls. These results suggest that UBE2C can be used as a potential therapeutic target for cervical and breast

  19. Ultraviolet radiation, human health, and the urban forest

    Science.gov (United States)

    Gordon M. Heisler; Richard H. Grant

    2000-01-01

    Excess exposure to ultraviolet (UV) radiation from the sun, particularly the ultraviolet B (UVB) portion, has been linked with adverse effects on human health ranging from skin cancers to eye diseases such as cataracts. Trees may prevent even greater disease rates in humans by reducing UV exposure. Tree shade greatly reduces UV irradiance when both the sun and sky are...

  20. Great magnetic storms

    International Nuclear Information System (INIS)

    Tsurutani, B.T.; Yen Te Lee; Tang, F.; Gonzalez, W.D.

    1992-01-01

    The five largest magnetic storms that occurred between 1971 and 1986 are studied to determine their solar and interplanetary causes. All of the events are found to be associated with high speed solar wind streams led by collisionless shocks. The high speed streams are clearly related to identifiable solar flares. It is found that (1) it is the extreme values of the southward interplanetary magnetic fields rather than solar wind speeds that are the primary causes of great magnetic storms, (2) shocked and draped sheath fields preceding the driver gas (magnetic cloud) are at least as effective in causing the onset of great magnetic storms (3 of 5 events ) as the strong fields within the driver gas itself, and (3) precursor southward fields ahead of the high speed streams allow the shock compression mechanism (item 2) to be particularly geoeffective

  1. The great intimidators.

    Science.gov (United States)

    Kramer, Roderick M

    2006-02-01

    After Disney's Michael Eisner, Miramax's Harvey Weinstein, and Hewlett-Packard's Carly Fiorina fell from their heights of power, the business media quickly proclaimed thatthe reign of abrasive, intimidating leaders was over. However, it's premature to proclaim their extinction. Many great intimidators have done fine for a long time and continue to thrive. Their modus operandi runs counter to a lot of preconceptions about what it takes to be a good leader. They're rough, loud, and in your face. Their tactics include invading others' personal space, staging tantrums, keeping people guessing, and possessing an indisputable command of facts. But make no mistake--great intimidators are not your typical bullies. They're driven by vision, not by sheer ego or malice. Beneath their tough exteriors and sharp edges are some genuine, deep insights into human motivation and organizational behavior. Indeed, these leaders possess political intelligence, which can make the difference between paralysis and successful--if sometimes wrenching--organizational change. Like socially intelligent leaders, politically intelligent leaders are adept at sizing up others, but they notice different things. Those with social intelligence assess people's strengths and figure out how to leverage them; those with political intelligence exploit people's weaknesses and insecurities. Despite all the obvious drawbacks of working under them, great intimidators often attract the best and brightest. And their appeal goes beyond their ability to inspire high performance. Many accomplished professionals who gravitate toward these leaders want to cultivate a little "inner intimidator" of their own. In the author's research, quite a few individuals reported having positive relationships with intimidating leaders. In fact, some described these relationships as profoundly educational and even transformational. So before we throw out all the great intimidators, the author argues, we should stop to consider what

  2. Great Lakes Energy Institute

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, J. Iwan [Case Western Reserve Univ., Cleveland, OH (United States)

    2012-11-18

    The vision of the Great Lakes Energy Institute is to enable the transition to advanced, sustainable energy generation, storage, distribution and utilization through coordinated research, development, and education. The Institute will place emphasis on translating leading edge research into next generation energy technology. The Institute’s research thrusts focus on coordinated research in decentralized power generation devices (e.g. fuel cells, wind turbines, solar photovoltaic devices), management of electrical power transmission and distribution, energy storage, and energy efficiency.

  3. Synergistic effects of sodium hypochlorite and ultraviolet radiation in reducing the levels of selected foodborne pathogenic bacteria.

    Science.gov (United States)

    Ha, Ji-Hyoung; Ha, Sang-Do

    2011-05-01

    The purpose of this study was to determine whether combined treatment would produce synergistic effects to facilitate the sterilization of food products during production relative to single treatment. To assess this hypothesis, we investigated the bactericidal effects of ultraviolet (UV) irradiation and a commercial chemical disinfectant, sodium hypochlorite (NaClO), on Bacillus cereus F4810/72, Cronobacter sakazakii KCTC 2949, Staphylococcus aureus ATCC 35556, Escherichia coli ATCC 10536, and Salmonella Typhimurium novobiocin/nalidixic acid in vitro. Various concentrations of NaClO (20, 60, 100, and 200 ppm NaClO) were tested along with exposure to UV radiation at various doses (6, 96, 216, 360, and 504 mW s/cm(2)). The combined NaClO/UV treatments resulted in greater reductions in bacterial counts than either treatment alone. The synergy values against B. cereus, C. sakazakii, S. aureus, Salmonella Typhimurium, and E. coli were 0.25-1.17, 0.33-1.97, 0.42-1.72, 0.02-1.44, and 0.01-0.85 log(10) CFU/mL, respectively. The results of this study suggest that a significant synergistic benefit results from combined NaClO/UV processing against food-borne pathogenic bacteria in vitro.

  4. Ultraviolet Type B-Radiation-Induced Hyperplasia and Seborrheic Keratosis is Reduced by Application of Commercial Sunscreens

    Directory of Open Access Journals (Sweden)

    Azad K Saeed1*, Snur MA Hassan1 and Nali A Maaruf2

    2016-11-01

    Full Text Available Fifty-six mice were classified into four groups; Group A (control group, n=8, Group B (exposure group, n=16, Group C (n=16 treated with sunscreen 15 minutes before UVB irradiations and group D (n=16 sunscreen treated 60 minutes before UVB exposure. Mice were irradiated 30 minutes 5days/week (12 weeks, and group C-D treated five days/week (12 weeks. Skin samples were taken in the mid and end of the experiment. The result of this study revealed that, epidermal thickness in group A was 7.155µm. At the mid-period of the experiment, severe epidermal hyperplasia was observed in group B with epidermal thickness 118.712µm, while in group C and D mild to moderate epidermal hyperplasia were noted with decreasing epidermal thickness to 64.154 and 90.042µm respectively. At the end of the experiment in Group B epidermal thickness reached to 281.35µm with seborrheic keratosis development, whereas in group C and D totally inhibited the development of seborrheic keratosis and epidermal thickness decreased again into 42.347 and 55.915µm. In conclusion, chronic UVB radiation-led to epidermal hyperplasia and seborrheic keratosis, sunscreen prevented the development of seborrheic keratosis and decreased the UVB-induced epidermal hyperplasia.

  5. Influence of Gamma Radiation on the Treatment of Sulfate Reducing Bacteria in the Injection Water Used for the Enhanced Oil Recovery

    International Nuclear Information System (INIS)

    El-Shahawy, M.R.; Ramzi, M.; Farag, R.M.

    2014-01-01

    The counts of sulfate reducing bacteria (SRB) in the water samples collected from the well head (formation water) and outlet of petroleum treatment plant (Produced water) in a petroleum field in middle delta- Egypt were determined. The data showed a low count of (SRB) in the collected formation water sample and there was an obvious increase in the bacterial counts which appeared in the produced water, that may reveal that the presence of appropriate conditions for the growth of (SRB) in the closed system in treatment plant. Two scale inhibitors were tested through jar test, the scale inhibitor I had maximum efficiency at 20 ppm, two SRB biocides were screened for their bactericidal activities. It was found that the biocides A was slightly superior in respect to the antibacterial efficacy compared to B in presence of 20 ppm scale inhibitor. These biocides were test for the study of the combined treatment with gamma radiation to maximize the efficiency on sulfate reducing bacteria using the minimum effective dose of both radiation and biocides to eliminate the negative impacts of the chemicals used and the radiation applied. The results demonstrated that, the lethal doses of biocides were (300 ppm) of biocides A or (400 ppm) of biocides B at 1 kGy irradiation dose. The treated produced water was evaluated in respect of enhanced oil recovery, the data showed increase of the recovery capacity by the irradiation and chemical treatment. This technology could be used for the water that are injected into reservoirs, and suitable for oil field and pipeline operators, and presented a viable bacteria control method

  6. Can low-dose CT with iterative reconstruction reduce both the radiation dose and the amount of iodine contrast medium in a dynamic CT study of the liver?

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroto; Okada, Masahiro; Hyodo, Tomoko; Hidaka, Syojiro; Kagawa, Yuki; Matsuki, Mitsuru; Tsurusaki, Masakatsu; Murakami, Takamichi, E-mail: murakami@med.kindai.ac.jp

    2014-04-15

    Purpose: To investigate whether low-dose dynamic CT of the liver with iterative reconstruction can reduce both the radiation dose and the amount of contrast medium. Materials and methods: This study was approved by our institutional review board. 113 patients were randomly assigned to one of two groups. Group A/group B (fifty-eight/fifty-five patients) underwent liver dynamic CT at 120/100 kV, with 0/40% adaptive statistical iterative reconstruction (ASIR), with a contrast dose of 600/480 mg I/kg, respectively. Radiation exposure was estimated based on the manufacturer's phantom data. The enhancement value of the hepatic parenchyma, vessels and the tumor-to-liver contrast of hepatocellular carcinomas (HCCs) were compared between two groups. Two readers independently assessed the CT images of the hepatic parenchyma and HCCs. Results: The mean CT dose indices: 6.38/4.04 mGy, the dose-length products: 194.54/124.57 mGy cm, for group A/group B. The mean enhancement value of the hepatic parenchyma and the tumor-to-liver contrast of HCCs with diameters greater than 1 cm in the post-contrast all phases did not differ significantly between two groups (P > 0.05). The enhancement values of vessels in group B were significantly higher than that in group A in the delayed phases (P < 0.05). Two reader's confidence levels for the hepatic parenchyma in the delayed phases and HCCs did not differ significantly between the groups (P > 0.05). Conclusions: Low-dose dynamic CT with ASIR can reduce both the radiation dose and the amount of contrast medium without image quality degradation, compared to conventional dynamic CT without ASIR.

  7. Radiation effects and radioprotectors

    Energy Technology Data Exchange (ETDEWEB)

    Purohit, R.K., E-mail: dr_rajendra_purohit@yahoo.co.in [Radiation Biology Laboratory, Department of Zoology, Govt. Dungar College, Bikaner (India); Bugalia, Saroj [Department of Zoology, S.K. Kalyan College, Sikar (India); Dakshene, Monika [Department of Chemistry, Govt. College, Kota (India)

    2012-07-01

    Radiation exposure causes damage to biological systems and these damages are mediated by the generation of free radicals and reactive oxygen species targeting vital cellular components such as DNA and membranes. DNA repair systems and the endogenous cellular biochemical defense mechanisms against reactive oxygen species and antioxidants enzymes like reduced Glutathione (GSH), Superoxide dismutase, Glutathione peroxidase catalase etc. fail upon exposures to higher as well as chronic radiation doses leading to alterations in cell functions, cell death or mutations. Radioprotectors prevent these alterations and protect cells and tissues from the deleterious effects of radiations. Radioprotectors are of great importance due to their possible and potential application during planned radiation exposures such as radiotherapy, diagnostic scanning, clean up operations in nuclear accidents, space expeditions etc. and Unplanned radiations exposures such as accidents in nuclear industry, nuclear terrorism, natural background radiation etc. Many of the available synthetic radioprotectors are toxic to mammalian system at doses required to be effective as radioprotector. Increasing uses of ionizing radiation have drawn the attention of many radiobiologists towards their undesired side effects produced in various tissues and for modifying them to facilitate the beneficial uses of radiation. Modification of radiation response is obtained by means of chemical substances that can significantly decrease the magnitude of response when present in a biological system during irradiation. Radioprotectors are chemicals that modify a cell's response to radiation. Radioprotectors are drugs that protect normal (non cancerous) cells from the damage caused by radiation therapy. These agents promote the repair of normal cells that are exposed to radiation. Various chemicals, like Cysteamine, MPG , WR-2721 have been tested for the protection against harmful effects of radiation. These radio

  8. Radiation effects and radioprotectors

    International Nuclear Information System (INIS)

    Purohit, R.K.; Bugalia, Saroj; Dakshene, Monika

    2012-01-01

    Radiation exposure causes damage to biological systems and these damages are mediated by the generation of free radicals and reactive oxygen species targeting vital cellular components such as DNA and membranes. DNA repair systems and the endogenous cellular biochemical defense mechanisms against reactive oxygen species and antioxidants enzymes like reduced Glutathione (GSH), Superoxide dismutase, Glutathione peroxidase catalase etc. fail upon exposures to higher as well as chronic radiation doses leading to alterations in cell functions, cell death or mutations. Radioprotectors prevent these alterations and protect cells and tissues from the deleterious effects of radiations. Radioprotectors are of great importance due to their possible and potential application during planned radiation exposures such as radiotherapy, diagnostic scanning, clean up operations in nuclear accidents, space expeditions etc. and Unplanned radiations exposures such as accidents in nuclear industry, nuclear terrorism, natural background radiation etc. Many of the available synthetic radioprotectors are toxic to mammalian system at doses required to be effective as radioprotector. Increasing uses of ionizing radiation have drawn the attention of many radiobiologists towards their undesired side effects produced in various tissues and for modifying them to facilitate the beneficial uses of radiation. Modification of radiation response is obtained by means of chemical substances that can significantly decrease the magnitude of response when present in a biological system during irradiation. Radioprotectors are chemicals that modify a cell's response to radiation. Radioprotectors are drugs that protect normal (non cancerous) cells from the damage caused by radiation therapy. These agents promote the repair of normal cells that are exposed to radiation. Various chemicals, like Cysteamine, MPG , WR-2721 have been tested for the protection against harmful effects of radiation. These radio

  9. Cancer Trials Ireland (ICORG) 06-34: A multi-centre clinical trial using three-dimensional conformal radiation therapy to reduce the toxicity of palliative radiation for lung cancer.

    Science.gov (United States)

    McDermott, Ronan L; Armstrong, John G; Thirion, Pierre; Dunne, Mary; Finn, Marie; Small, Cormac; Byrne, Mary; O'Shea, Carmel; O'Sullivan, Lydia; Shannon, Aoife; Kelly, Emma; Hacking, Dayle J

    2018-05-01

    Cancer Trials Ireland (ICORG) 06-34: A multi-centre clinical trial using three-dimensional conformal radiation therapy to reduce the toxicity of palliative radiation for lung cancer. NCT01176487. Trials of radiation therapy for the palliation of intra-thoracic symptoms from locally advanced non-small cell lung cancer (NSCLC) have concentrated on optimising fractionation and dose schedules. In these trials, the rates of oesophagitis induced by this "palliative" therapy have been unacceptably high. In contrast, this non-randomised, single-arm trial was designed to assess if more technically advanced treatment techniques would result in equivalent symptom relief and reduce the side-effect of symptomatic oesophagitis. Thirty-five evaluable patients with symptomatic locally advanced or metastatic NSCLC were treated using a three-dimensional conformal technique (3-DCRT) and standardised dose regimens of 39 Gy in 13 fractions, 20 Gy in 5 fractions or 17 Gy in 2 fractions. Treatment plans sought to minimise oesophageal dose. Oesophagitis was recorded during treatment, at two weeks, one month and three months following radiation therapy and 3-6 monthly thereafter. Mean dose to the irradiated oesophagus was calculated for all treatment plans. Five patients (14%) had experienced grade 2 oesophagitis or dysphagia or both during treatment and 2 other patients had these side effects at the 2-week follow-up. At follow-up of one month after therapy, there was no grade two or higher oesophagitis or dysphagia reported. 22 patients were eligible for assessment of late toxicity. Five of these patients reported oesophagitis or dysphagia (one had grade 3 dysphagia, two had grade 2 oesophagitis, one of whom also had grade 2 dysphagia). Quality of Life (QoL) data at baseline and at 1-month follow up were available for 20 patients. At 1-month post radiation therapy, these patients had slightly less trouble taking a short walk, less shortness of breath, did not feel as weak, had

  10. Selective emission multilayer coatings for a molybdenum thermophotovoltaic radiator

    Science.gov (United States)

    Cockeram, Brian Vern

    2004-01-27

    Multilayer coating designs have been developed to provide selective emission for a molybdenum thermophotovoltaic (TPV) radiator surface. These coatings increase the surface emissivity of a molybdenum TPV radiator substrate in the wavelength range that matches the bandgap of the TPV cells to increase the power density of the TPV system. Radiator emission at wavelengths greater than the bandgap energy of the TPV cells is greatly reduced through the use of these coatings, which significantly increases the efficiency of the TPV system. The use of this coating greatly improves the performance of a TPV system, and the coating can be tailored to match the bandgap of any practical TPV system.

  11. Degradation of Transformer Oil (PCB Compounds by Microwave Radiation, Ethanol Solvent, Hydrogen Peroxide and Dioxide Titanium for Reducing Environmental Hazards

    Directory of Open Access Journals (Sweden)

    Reza Tajik

    2013-02-01

    Full Text Available Background: Poly chlorinated biphenyls (PCBs are a class of chlorinated organic chemicals that do not easily degrade in the environment. This study was conducted to determine the effect of microwave rays, hydrogen peroxide, dioxide titanium and ethanol solvent on the degradation of PCBs. Methods: A 900w domestic MW oven with a fixed frequency of 2450 MHZ was used to provide MW irradiation. Ray powers were used in 540, 720, and 900w. A hole was made on the top portion of the oven and a Pyrex vessel reactor (250ml volume was connected to condensing system with a Pyrex tube connector. The PCBs were analyzed by GC-ECD. Results: The degradation of total PCBs was 54.62%, 79.71%, and 95.76% in terms of their ratio to solvent with transformer oil at 1:1, 2:1, and 3:1, respectively. The degradation of total PCBs was 84.27%, 89.18%, and 96.1% when using 540, 720, and 900W microwave radiation, respectively. The degradation of total PCBs was 70.72%, 93.02%, 94.16, 95.23% and 96.1% when not using H2O2/ Tio2 and using 20% H2O2 and 0.05, 0.1, 0.15, and 0.2g Tio2, respectively. Conclusion: In the present study, the optimum conditions to decompose PCBs efficiently included 50 ml volume of ratio to solvent with transformer oil (3:1, sodium hydroxide solution (0.2N 1 cc, use of 20% hydrogen peroxide of total volume of samples, dioxide titanium (0.2g, and irradiation for 9 minutes. Under these optimum conditions, efficiency of PCBs decomposition increased.

  12. SU-E-T-21: A Novel Sampling Algorithm to Reduce Intensity-Modulated Radiation Therapy (IMRT) Optimization Time

    International Nuclear Information System (INIS)

    Tiwari, P; Xie, Y; Chen, Y; Deasy, J

    2014-01-01

    Purpose: The IMRT optimization problem requires substantial computer time to find optimal dose distributions because of the large number of variables and constraints. Voxel sampling reduces the number of constraints and accelerates the optimization process, but usually deteriorates the quality of the dose distributions to the organs. We propose a novel sampling algorithm that accelerates the IMRT optimization process without significantly deteriorating the quality of the dose distribution. Methods: We included all boundary voxels, as well as a sampled fraction of interior voxels of organs in the optimization. We selected a fraction of interior voxels using a clustering algorithm, that creates clusters of voxels that have similar influence matrix signatures. A few voxels are selected from each cluster based on the pre-set sampling rate. Results: We ran sampling and no-sampling IMRT plans for de-identified head and neck treatment plans. Testing with the different sampling rates, we found that including 10% of inner voxels produced the good dose distributions. For this optimal sampling rate, the algorithm accelerated IMRT optimization by a factor of 2–3 times with a negligible loss of accuracy that was, on average, 0.3% for common dosimetric planning criteria. Conclusion: We demonstrated that a sampling could be developed that reduces optimization time by more than a factor of 2, without significantly degrading the dose quality

  13. Radiation shielding cloth

    International Nuclear Information System (INIS)

    Ijiri, Yasuo; Fujinuma, Tadashi; Tamura, Shoji.

    1989-01-01

    Radiation shielding cloth having radiation shielding layers comprising a composition of inorganic powder of high specific gravity and rubber are excellentin flexibility and comfortable to put on. However, since they are heavy in the weight, operators are tired upon putting them for a long time. In view of the above, the radiation ray shielding layers are prepared by calendering sheets obtained by preliminary molding of the composition to set the variation of the thickness within a range of +15% to -0% of prescribed thickness. Since the composition of inorganic powder at high specific gravity and rubber used for radiation ray shielding comprises a great amount of inorganic powder at high specific gravity blended therein, it is generally poor in fabricability. Therefor, it is difficult to attain fine control for the sheet thickness by merely molding a composition block at once. Then, the composition is at first preliminarily molded into a sheet-like shape which is somewhat thickener than the final thickness and then finished by calendering, by which the thickness can be reduced in average as compared with conventional products while keeping the prescribed thickness and reducing the weight reduce by so much. (N.H.)

  14. Idiopathic great saphenous phlebosclerosis.

    Directory of Open Access Journals (Sweden)

    Ahmadreza Jodati

    2013-06-01

    Full Text Available Arterial sclerosis has been extensively described but reports on venous sclerosis are very sparse. Phlebosclerosis refers to the thickening and hardening of the venous wall. Despite its morphological similarities with arteriosclerosis and potential morbid consequences, phlebosclerosis has gained only little attention. We report a 72 year old male with paralysis and atrophy of the right leg due to childhood poliomyelitis who was referred for coronary artery bypass surgery. The great saphenous vein, harvested from the left leg, showed a hardened cord-like obliterated vein. Surprisingly, harvested veins from the atrophic limb were normal and successfully used for grafting.

  15. Great software debates

    CERN Document Server

    Davis, A

    2004-01-01

    The industry’s most outspoken and insightful critic explains how the software industry REALLY works. In Great Software Debates, Al Davis, shares what he has learned about the difference between the theory and the realities of business and encourages you to question and think about software engineering in ways that will help you succeed where others fail. In short, provocative essays, Davis fearlessly reveals the truth about process improvement, productivity, software quality, metrics, agile development, requirements documentation, modeling, software marketing and sales, empiricism, start-up financing, software research, requirements triage, software estimation, and entrepreneurship.

  16. Making Psychotherapy Great Again?

    Science.gov (United States)

    Plakun, Eric M

    2017-05-01

    Psychotherapy never stopped being as "great" as other treatments. This column explores the evidence base for both psychotherapy and medications, using depression as a specific example. The limitations are comparable for psychotherapy and medication, with much of the evidence based on small degrees of "statistically significant" rather than "clinically meaningful" change. Our field's biomedical emphasis leads to a false assumption that most patients present with single disorders, when comorbidity is the rule rather than the exception. This false assumption contributes to limitations in the evidence base and in our ability to treat patients optimally.

  17. One-step synthesis of Pt-reduced graphene oxide composites based on high-energy radiation technique

    International Nuclear Information System (INIS)

    Liu, Xuqiang; Jiang, Shubin; Huang, Wei; Song, Hongtao

    2014-01-01

    In this paper, we introduce a novel 60 Co-ray-irradiation-based one-step synthesis method of Pt-reduced graphene oxide composites (Pt-RGO) in acid aqueous solution. The compositional distribution of the particles in the samples was characterized by transmission electron microscopy. The structure and composition of the nanocomposite has been determined with a scanning electron microscope (SEM) equipped with an energy dispersion X-ray (EDS) analyzer. Surface enhanced Raman scattering (SERS) of graphene deposited by the Pt nanoparticles were investigated with the 514.5 nm excitation. It was found that small-sized and highly-dispersed Pt nanoparticles could easily grow on the RGO surface under acidic conditions. In addition, the obtained homogeneous dispersions exhibit long-term stability, which will facilitate the production of homogeneous composites. (orig.)

  18. Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Gi [Ajou University School of Medicine, Ajou University Medical Center, Department of Radiology, Yeongtong-gu, Suwon (Korea, Republic of); Lee, Ho-Joon; Lee, Seung-Koo; Kim, Myung-Joon [Severance Hospital, Yonsei University College of Medicine, Department of Radiology and Research Institute of Radiological Science, Seodaemun-gu, Seoul (Korea, Republic of); Kim, Hyun Ji [Ajou University School of Medicine, Office of Biostatistics, Department of Humanities and Social Medicine, Yeongtong-gu, Suwon (Korea, Republic of)

    2017-09-15

    To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols. A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for <3-year-old patients and applied 30% ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V. Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P < 0.001). Qualitative analysis showed higher gray-white matter differentiation and sharpness and preserved overall diagnostic quality in the images with ASIR-V. Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality. (orig.)

  19. Head CT: Image quality improvement with ASIR-V using a reduced radiation dose protocol for children

    International Nuclear Information System (INIS)

    Kim, Hyun Gi; Lee, Ho-Joon; Lee, Seung-Koo; Kim, Myung-Joon; Kim, Hyun Ji

    2017-01-01

    To investigate the quality of images reconstructed with adaptive statistical iterative reconstruction V (ASIR-V), using pediatric head CT protocols. A phantom was scanned at decreasing 20% mA intervals using our standard pediatric head CT protocols. Each study was then reconstructed at 10% ASIR-V intervals. After the phantom study, we reduced mA by 10% in the protocol for <3-year-old patients and applied 30% ASIR-V and by 30% in the protocol for 3- to 15-year-old patients and applied 40% ASIR-V. Increasing the percentage of ASIR-V resulted in lower noise and higher contrast-to-noise ratio (CNR) and preserved spatial resolution in the phantom study. Compared to a conventional-protocol, reduced-dose protocol with ASIR-V achieved 12.8% to 34.0% of dose reduction and showed images of lower noise (9.22 vs. 10.73, P = 0.043) and higher CNR in different levels (centrum semiovale, 2.14 vs. 1.52, P = 0.003; basal ganglia, 1.46 vs. 1.07, P = 0.001; and cerebellum, 2.18 vs. 1.33, P < 0.001). Qualitative analysis showed higher gray-white matter differentiation and sharpness and preserved overall diagnostic quality in the images with ASIR-V. Use of ASIR-V allowed a 12.8% to 34.0% dose reduction in each age group with potential to improve image quality. (orig.)

  20. Soluble TGF-β type II receptor gene therapy reduces TGF-β activity in irradiated lung tissue and protects lungs from radiation-induced injury

    International Nuclear Information System (INIS)

    Vujaskovic, Z.; Rabbani, Z.; Zhang, X.; Samulski, T.V.; Li, C.-Y.; Anscher, M.S.

    2003-01-01

    Full text: The objective was to determine whether administration of recombinant human adenoviral vector carrying soluble TGF-β1 type II receptor (TβR-II) gene reduces availability of active TGFβ1 and protects lung from radiation-induced injury. Female Fisher-344 rats were randomized into four groups to receive: 1) Control 2) Adenoviral green fluorescent protein vector (AdGFP) alone 3) Radiation (RT) + Adenoviral vector with TGF-β1 type II receptor gene (AdexTβR-II-Fc) 4) RT alone. Animals were irradiated to right hemithorax using a single dose of 30 Gy. The packaging and production of a recombinant adenovirus carrying the fused human TβR-II-IgG1 Fc gene was achieved by use of the AdEasy system. The treatment vector AdexTbR-II-Fc (1.5*1010 PFU) and control vector AdGFP (1*109 PFU) were injected i.v. 24 hrs after RT. Respiratory rate was measured as an index of pulmonary function weekly for 5 weeks post RT. Structural damage was scored histologically. Immunohistochemistry was performed to identify activated macrophages. ELISA was used to quantify active TGF-β1 in tissue homogenate. Western blot was used to determine TβR-II expression in plasma and lung tissue. Animals receiving treatment vector AdexTbR-II-Fc have elevated plasma levels of soluble TβR-II at 24 and 48 hours after injection. In the RT+AdexTbR-II-Fc group, there was a significant reduction in respiratory rate (p = 0.002) at four weeks after treatment compared to RT alone group. Histology revealed a significant reduction in lung structural damage in animals receiving gene therapy after RT vs RT alone (p=0.0013). There was also a decrease in the number of activated macrophage (p= 0.02) in RT+AdexTbR-II-Fc group vs RT alone. The tissue protein expression of active TGF-β1 was significantly reduced in rats receiving RT+AdexTbR-II-Fc treatment (p<0.05). This study shows the ability of adenovirus mediated soluble TβR-II gene therapy to reduce tissue levels of active TGF-β1 and ameliorate radiation

  1. Radiation injury

    International Nuclear Information System (INIS)

    Hubner, K.F.

    1988-01-01

    Radiation accidents and incidents continue to be of great interest and concern to the public. Issues such as the threat of nuclear war, the Chernobyl reactor accident, or reports of sporadic incidences of accidental radiation exposure keep this interest up and maintain a high level of fear among the public. In this climate of real concern and radiation phobia, physicians should not only be prepared to answer questions about acute or late effects of ionizing radiation, but also be able to participate in the initial assessment and management of individuals who have been exposed to ionizing radiation or contaminated with radioactive material. Some of the key facts about radiation injury and its medical treatment are discussed by the author

  2. Cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Capdevielle, J N

    1984-01-01

    First, the different instruments and techniques of cosmic particle detection are presented. Then the passage of the cosmic particles through the atmosphere is studied: electrons, photons, muons. The collective behavior of the different categories is also studied, the electromagnetic cascade is distinguished from the hadron cascade. Through the principal physical properties of the radiation and the medium, the ''mean'' aspects of the radiation are then successively dealt with out of the atmosphere, at different altitudes until the sea level, then at great depths. A chapter is devoted to cosmic radiation of more than 10,000 GeV, studied separately. Then solar radiation in universe is studied through their propagation in solar system and their origin. At last, the cosmic radiation effects are studied in environment (cosmic biophysics) and some applications of cosmic radiation are presented.

  3. Linear Energy Transfer Painting With Proton Therapy: A Means of Reducing Radiation Doses With Equivalent Clinical Effectiveness

    International Nuclear Information System (INIS)

    Fager, Marcus; Toma-Dasu, Iuliana; Kirk, Maura; Dolney, Derek; Diffenderfer, Eric S.; Vapiwala, Neha; Carabe, Alejandro

    2015-01-01

    Purpose: The purpose of this study was to propose a proton treatment planning method that trades physical dose (D) for dose-averaged linear energy transfer (LET d ) while keeping the radiobiologically weighted dose (D RBE ) to the target the same. Methods and Materials: The target is painted with LET d by using 2, 4, and 7 fields aimed at the proximal segment of the target (split target planning [STP]). As the LET d within the target increases with increasing number of fields, D decreases to maintain the D RBE the same as the conventional treatment planning method by using beams treating the full target (full target planning [FTP]). Results: The LET d increased 61% for 2-field STP (2STP) compared to FTP, 72% for 4STP, and 82% for 7STP inside the target. This increase in LET d led to a decrease of D with 5.3 ± 0.6 Gy for 2STP, 4.4 ± 0.7 Gy for 4STP, and 5.3 ± 1.1 Gy for 7STP, keeping the DRBE at 90% of the volume (DRBE, 90) constant to FTP. Conclusions: LET d painting offers a method to reduce prescribed dose at no cost to the biological effectiveness of the treatment

  4. Linear Energy Transfer Painting With Proton Therapy: A Means of Reducing Radiation Doses With Equivalent Clinical Effectiveness

    Energy Technology Data Exchange (ETDEWEB)

    Fager, Marcus, E-mail: Marcus.Fager@UPHS.UPenn.edu [Department of Radiation Oncology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Medical Radiation Physics, Stockholm University, Stockholm (Sweden); Toma-Dasu, Iuliana [Medical Radiation Physics, Stockholm University and Karolinska Institutet, Stockholm (Sweden); Kirk, Maura; Dolney, Derek; Diffenderfer, Eric S.; Vapiwala, Neha [Department of Radiation Oncology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Carabe, Alejandro, E-mail: Alejandro.Carabe-Fernandez@UPHS.UPenn.edu [Department of Radiation Oncology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania (United States)

    2015-04-01

    Purpose: The purpose of this study was to propose a proton treatment planning method that trades physical dose (D) for dose-averaged linear energy transfer (LET{sub d}) while keeping the radiobiologically weighted dose (D{sub RBE}) to the target the same. Methods and Materials: The target is painted with LET{sub d} by using 2, 4, and 7 fields aimed at the proximal segment of the target (split target planning [STP]). As the LET{sub d} within the target increases with increasing number of fields, D decreases to maintain the D{sub RBE} the same as the conventional treatment planning method by using beams treating the full target (full target planning [FTP]). Results: The LET{sub d} increased 61% for 2-field STP (2STP) compared to FTP, 72% for 4STP, and 82% for 7STP inside the target. This increase in LET{sub d} led to a decrease of D with 5.3 ± 0.6 Gy for 2STP, 4.4 ± 0.7 Gy for 4STP, and 5.3 ± 1.1 Gy for 7STP, keeping the DRBE at 90% of the volume (DRBE, 90) constant to FTP. Conclusions: LET{sub d} painting offers a method to reduce prescribed dose at no cost to the biological effectiveness of the treatment.

  5. The rate of repeating X-rays in the medical centers of Jenin District/Palestine and how to reduce patient exposure to radiation

    Science.gov (United States)

    Assi, Abed Al Nasser

    2018-03-01

    Reduction of the patient's received radiation dose to as low as reasonably achievable (ALARA) is based on recommendations of radiation protection organizations such as the International Commission on Radiological Protection (ICRP) and the National Radiological Protection Board (NRPB). The aim of this study was to explore the frequency and characteristics of rejected / repeated radiographic films in governmental and private centers in Jenin city. The radiological centers were chosen based on their high volume of radiographic studies. The evaluation was carried out over a period of four months. The collected data were compiled at the end of each week and entered into a computer for analysis at the end of study. Overall 5000 films (images) were performed in four months, The average repeat rate of radiographic images was 10% (500 films). Repetition rate was the same for both thoracic and abdominal images (42%). The main reason for repeating imaging was inadequate imaging quality (58.2%) and poor film processing (38%). Human error was the most likely reason necessitating the repetition of the radiographs (48 %). Infant and children groups comprised 85% of the patient population that required repetition of the radiographic studies. In conclusion, we have a higher repetition rate of imaging studies compared to the international standards (10% vs. 4-6%, respectively). This is especially noticeable in infants and children, and mainly attributed to human error in obtaining and processing images. This is an important issue that needs to be addressed on a national level due to the ill effects associated with excessive exposure to radiation especially in children, and to reduce cost of the care delivered.

  6. An automated electronic system for managing radiation treatment plan peer review reduces missed reviews at a large, high-volume academic center.

    Science.gov (United States)

    Gabriel, Peter E; Woodhouse, Kristina D; Lin, Alexander; Finlay, Jarod C; Young, Richard B; Volz, Edna; Hahn, Stephen M; Metz, James M; Maity, Amit

    Assuring quality in cancer care through peer review has become increasingly important in radiation oncology. In 2012, our department implemented an automated electronic system for managing radiation treatment plan peer review. The purpose of this study was to compare the overall impact of this electronic system to our previous manual, paper-based system. In an effort to improve management, an automated electronic system for case finding and documentation of review was developed and implemented. The rates of missed initial reviews, late reviews, and missed re-reviews were compared for the pre- versus postelectronic system cohorts using Pearson χ 2 test and relative risk. Major and minor changes or recommendations were documented and shared with the assigned clinical provider. The overall rate of missed reviews was 7.6% (38/500) before system implementation versus 0.4% (28/6985) under the electronic system (P automated system. Missed re-reviews occurred in 23.1% (3/13) of courses in the preelectronic system cohort and 6.6% (10/152) of courses in the postelectronic system cohort (P = .034). Late reviews were more frequent during high travel or major holiday periods. Major changes were recommended in 2.2% and 2.8% in the pre- versus postelectronic systems, respectively. Minor changes were recommended in 5.3% of all postelectronic cases. The implementation of an automated electronic system for managing peer review in a large, complex department was effective in significantly reducing the number of missed reviews and missed re-reviews when compared to our previous manual system. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  7. Valproic acid reduces hair loss and improves survival in patients receiving temozolomide-based radiation therapy for high-grade glioma.

    Science.gov (United States)

    Watanabe, Shinichi; Kuwabara, Yui; Suehiro, Satoshi; Yamashita, Daisuke; Tanaka, Mamoru; Tanaka, Akihiro; Ohue, Shiro; Araki, Hiroaki

    2017-03-01

    Valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, is also used to manage seizures in glioblastoma patients. HDAC inhibitors can protect normal cells and tissues from the deleterious effects of radiotherapy, and VPA is reported to improve the survival of glioblastoma patients receiving chemoradiation therapy. VPA also promotes hair growth, and thus has the potential to reduce the radiotherapy side effect of hair loss while improving the survival of patients with glioblastoma. The purpose of this study was to determine whether VPA use during radiotherapy for high-grade glioma is associated with decreased side effects of radiotherapy and an improvement in overall survival (OS) and progression-free survival (PFS). Medical records of 112 patients with high-grade glioma were retrospectively reviewed. We grouped patients by VPA use or non-use during radiotherapy, and evaluated hair loss, OS, and PFS. The radiation dose and fractionation at the onset of hair loss were 4 Gy and two fractions higher, respectively, in the VPA group compared with the VPA non-use group (P hair loss and improvement in survival. Hair loss prevention benefits patients suffering from the deleterious effects of radiation.

  8. Construction of radiation-reduced hybrids and their use in mapping of microclones from chromosome 10p11.2-q11.2

    International Nuclear Information System (INIS)

    Fujita, Shoichi; Shin, Eisei; Nakamura, Tsutomu; Kurahashi, Hiroki; Mori, Takesada; Takai, Shin-ichiro; Nishisho, Isamu; Kaneda, Yasufumi; Tanaka, Kiyoji.

    1993-01-01

    Radiation-reduced hybrids for mapping of DNA markers in the pericentromeric region of chromosome 10 were developed. A Chinese hamster/human somatic cell hybrid (762-8A) carrying chromosomes 10 and Y as the only human material were exposed to 40,000 rads of irradiation and then rescued by fusion with non-irradiated recipient Chinese hamster cells (GM459). Southern hybridization analyses revealed that 10 of 128 HAT-resistant clones contained human chromosomal fragments corresponding to at least one marker locus between FNRB (10p11.2) and RBP3 (10q11.2). These hybrids were then used to map microdissection clones previously isolated and roughly mapped to this chromosomal region by fluorescence in situ hybridization (FISH). Two of the six microclones studies could be mapped to the proximity of the D10S102 locus. These radiation hybrids are useful for the construction of refined genetic maps of the pericentromeric region of chromosome 10. (author) 50 refs

  9. Augmented Quadruple-Phase Contrast Media Administration and Triphasic Scan Protocol Increases Image Quality at Reduced Radiation Dose During Computed Tomography Urography.

    Science.gov (United States)

    Saade, Charbel; Mohamad, May; Kerek, Racha; Hamieh, Nadine; Alsheikh Deeb, Ibrahim; El-Achkar, Bassam; Tamim, Hani; Abdul Razzak, Farah; Haddad, Maurice; Abi-Ghanem, Alain S; El-Merhi, Fadi

    The aim of this article was to investigate the opacification of the renal vasculature and the urogenital system during computed tomography urography by using a quadruple-phase contrast media in a triphasic scan protocol. A total of 200 patients with possible urinary tract abnormalities were equally divided between 2 protocols. Protocol A used the conventional single bolus and quadruple-phase scan protocol (pre, arterial, venous, and delayed), retrospectively. Protocol B included a quadruple-phase contrast media injection with a triphasic scan protocol (pre, arterial and combined venous, and delayed), prospectively. Each protocol used 100 mL contrast and saline at a flow rate of 4.5 mL. Attenuation profiles and contrast-to-noise ratio of the renal arteries, veins, and urogenital tract were measured. Effective radiation dose calculation, data analysis by independent sample t test, receiver operating characteristic, and visual grading characteristic analyses were performed. In arterial circulation, only the inferior interlobular arteries in both protocols showed a statistical significance (P contrast-to-noise ratio than protocol A (protocol B: 22.68 ± 13.72; protocol A: 14.75 ± 5.76; P contrast media and triphasic scan protocol usage increases the image quality at a reduced radiation dose.

  10. Great Britain at CERN

    CERN Multimedia

    2006-01-01

    From 14 to 16 November 2006 Administration Building, Bldg. 60/61 - ground and 1st floor 09.30 - 17.30 Fifteen companies will present their latest technologies at the 'Great Britain at CERN' exhibition. British industry will exhibit products and technologies related to the field of particle physics. The main fields represented will be computing technologies, electrical engineering, electronics, mechanical engineering, vacuum & low temperature technologies and particle detectors. The exhibition is organised by BEAMA Exhibitions (the British Electrotechnical and Allied Manufacturers Association). Below you will find: a list of the exhibitors. A detailed programme will be available in due course: from your Departmental secretariat, from the Reception information desk, Building 33, at the exhibition itself. A detailed list of the companies is available at the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm LIST OF EXHIBITORS 3D Metrics Almat...

  11. Great Britain at CERN

    CERN Multimedia

    2006-01-01

    From 14 to 16 November 2006 Administration Building, Bldg. 60/61 - ground and 1st floor 09.30 - 17.30 Fifteen companies will present their latest technologies at the 'Great Britain at CERN' exhibition. British industry will exhibit products and technologies related to the field of particle physics. The main fields represented will be computing technologies, electrical engineering, electronics, mechanical engineering, vacuum & low temperature technologies and particle detectors. The exhibition is organised by BEAMA Exhibitions (the British Electrotechnical and Allied Manufacturers Association). Below you will find: a list of the exhibitors. A detailed programme will be available in due course: from your Departmental secretariat, from the Reception information desk, Building 33, at the exhibition itself. A detailed list of the companies is available at the following FI link: http://fi-dep.web.cern.ch/fi-dep/structure/memberstates/exhibitions_visits.htm LIST OF EXHIBITORS 3D Metrics Alma...

  12. Radiation transport in MEDUSA

    International Nuclear Information System (INIS)

    Rose, S.J.; Evans, R.G.

    1983-09-01

    The transport of energy by X-ray photons has been included in the lD Lagrangian hydrodynamics code, MEDUSA. Calculations of the implosion by 0.53 μm laser irradiation of plastic and glass microballoons of current interest at the Central Laser Facility show that radiation preheats the fill gas and alters the temperature and density profiles during the implosion. A lower maximum gas temperature is obtained and this results, for a DT gas fill, in a greatly reduced neutron yield. (author)

  13. Radiation and/or hyperthermia sensitivity of human melanoma cells grown for several days in media with reduced pH

    International Nuclear Information System (INIS)

    Zoelzer, F.; Streffer, C.

    1999-01-01

    MeWo cells were used throughout. Cells were incubated for 0, 3 or 6 days in media with pH 6.5, 6.7, 6.9, 7.1 or 7.3. The sensitivity against 250 kV X-rays and hyperthermia at 43 C were determined in the colony-forming assay. The intracellular pH was measured flow cytometrically using 5(and 6)-carboxyfluoroescein. Calibration curves were established with cells incubated in different buffers containing nigericin to equilibrate intra- and extracellular pH. Results: Cell growth was optimal with pH 7.3 and 7.1 in the medium, somewhat reduced at pH 6.9, and largely inhibited at pH 6.7 and 6.5. Radiation and/or hyperthermia sensitivities were noticeably increased after several days of incubation at reduced pH; the surviving fraction after 4 Gy and 1 h at 43 C either alone or in combination being a factor of 2 to 4 lower at pH 6.5 than at 7.3. These changes in sensitivity could not be correlated with changes in the intracellular pH. Cells seemed to be capable of regulating this parameter very well; the flow cytometric measurements revealed that the intracellular pH was 7.2±0.2 irrespective of the extracellular pH in the range considered here. Conclusions: In contrast to the almost generally accepted hypothesis that intracellular pH is decisive for the heat sensitivity, the human melanoma cells studied here became sensitive after a few days of incubation under acidic conditions without changes in the intracellular pH. Other factors seem to be influencing the cellular response to radiation and/or heat under chronically low pH. (orig./MG) [de

  14. Minibeam Therapy With Protons and Light Ions: Physical Feasibility and Potential to Reduce Radiation Side Effects and to Facilitate Hypofractionation

    Energy Technology Data Exchange (ETDEWEB)

    Dilmanian, F. Avraham, E-mail: avraham.dilmanian@stonybrook.edu [Departments of Radiation Oncology, Neurology, and Radiology, Stony Brook University Medical Center, Stony Brook, New York (United States); Eley, John G. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Krishnan, Sunil [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2015-06-01

    Purpose: Despite several advantages of proton therapy over megavoltage x-ray therapy, its lack of proximal tissue sparing is a concern. The method presented here adds proximal tissue sparing to protons and light ions by turning their uniform incident beams into arrays of parallel, small, or thin (0.3-mm) pencil or planar minibeams, which are known to spare tissues. As these minibeams penetrate the tissues, they gradually broaden and merge with each other to produce a solid beam. Methods and Materials: Broadening of 0.3-mm-diameter, 109-MeV proton pencil minibeams was measured using a stack of radiochromic films with plastic spacers. Monte Carlo simulations were used to evaluate the broadening in water of minibeams of protons and several light ions and the dose from neutron generated by collimator. Results: A central parameter was tissue depth, where the beam full width at half maximum (FWHM) reached 0.7 mm, beyond which tissue sparing decreases. This depth was 22 mm for 109-MeV protons in a film stack. It was also found by simulations in water to be 23.5 mm for 109 MeV proton pencil minibeams and 26 mm for 116 MeV proton planar minibeams. For light ions, all with 10 cm range in water, that depth increased with particle size; specifically it was 51 mm for Li-7 ions. The ∼2.7% photon equivalent neutron skin dose from the collimator was reduced 7-fold by introducing a gap between the collimator and the skin. Conclusions: Proton minibeams can be implemented at existing particle therapy centers. Because they spare the shallow tissues, they could augment the efficacy of proton therapy and light particle therapy, particularly in treating tumors that benefit from sparing of proximal tissues such as pediatric brain tumors. They should also allow hypofractionated treatment of all tumors by allowing the use of higher incident doses with less concern about proximal tissue damage.

  15. Reduced radiation dose for elective nodal irradiation in node-negative anal cancer: back to the roots

    Energy Technology Data Exchange (ETDEWEB)

    Henkenberens, Christoph; Meinecke, Daniela; Bremer, Michael; Christiansen, Hans [Medizinische Hochschule Hannover, Hannover Medical School, Department of Radiation Oncology, Klinik fuer Strahlentherapie und Spezielle Onkologie, Hannover (Germany); Michael, Stoll [End- und Dickdarmzentrum Hannover, Hannover (Germany)

    2015-11-15

    Chemoradiation (CRT) is the standard of care in patients with node-positive (cN+) and node-negative (cN0) anal cancer. Depending on the tumor size (T-stage), total doses of 50-60 Gray (Gy) in daily fractions of 1.8-2.0 Gy are usually applied to the tumor site. Inguinal and iliac lymph nodes usually receive a dose of ≥ 45 Gy. Since 2010, our policy has been to apply a reduced total dose of 39.6 Gy to uninvolved nodal regions. This paper provides preliminary results of the efficacy and safety of this protocol. Overall, 30 patients with histologically confirmed and node-negative anal cancer were treated in our department from 2009-2014 with definitive CRT. Histology all cases showed squamous cell carcinoma. A total dose of 39.6 Gy [single dose (SD) 1.8 Gy] was delivered to the iliac/inguinal lymph nodes. The area of the primary tumor received 50-59.4 Gy, depending on the T-stage. In parallel with the irradiation, 5-fluorouracil (5-FU) at a dose of 1000 mg/m{sup 2} was administered by continuous intravenous infusion over 24 h on days 1-4 and 29-32, and mitomycin C (MMC) at a dose of 10 mg/m{sup 2} (maximum absolute dose 14 mg) was administered on days 1 and 29. The distribution of the tumor stages was as follows: T1, n = 8; T2, n = 17; T3 n = 3. Overall survival (OS), local control (LC) of the lymph nodes, colostomy-free survival (CFS), and acute and chronic toxicities were assessed. The median follow-up was 27.3 months (range 2.7-57.4 months). Three patients (10.0 %) died, 2 of cardiopulmonary diseases and one of liver failure, yielding a 3-year OS of 90.0 %. Two patients (6.7 %) relapsed early and received salvage colostomies, yielding a 3-year CFS of 93.3 %. No lymph node relapses were observed, giving a lymph node LC of 100 %. According to the Common Terminology Criteria for Adverse Events Version 4.0 (CTCAE V. 4.0), there were no grade IV gastrointestinal or genitourinary acute toxicities. Seven patients showed acute grade III perineal skin toxicity. Acute grade

  16. Proton Arc Reduces Range Uncertainty Effects and Improves Conformality Compared With Photon Volumetric Modulated Arc Therapy in Stereotactic Body Radiation Therapy for Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Seco, Joao, E-mail: jseco@partners.org [Francis H. Burr Proton Therapy Center, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States); Gu, Guan; Marcelos, Tiago; Kooy, Hanne; Willers, Henning [Francis H. Burr Proton Therapy Center, Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts (United States)

    2013-09-01

    Purpose: To describe, in a setting of non-small cell lung cancer (NSCLC), the theoretical dosimetric advantages of proton arc stereotactic body radiation therapy (SBRT) in which the beam penumbra of a rotating beam is used to reduce the impact of range uncertainties. Methods and Materials: Thirteen patients with early-stage NSCLC treated with proton SBRT underwent repeat planning with photon volumetric modulated arc therapy (Photon-VMAT) and an in-house-developed arc planning approach for both proton passive scattering (Passive-Arc) and intensity modulated proton therapy (IMPT-Arc). An arc was mimicked with a series of beams placed at 10° increments. Tumor and organ at risk doses were compared in the context of high- and low-dose regions, represented by volumes receiving >50% and <50% of the prescription dose, respectively. Results: In the high-dose region, conformality index values are 2.56, 1.91, 1.31, and 1.74, and homogeneity index values are 1.29, 1.22, 1.52, and 1.18, respectively, for 3 proton passive scattered beams, Passive-Arc, IMPT-Arc, and Photon-VMAT. Therefore, proton arc leads to a 30% reduction in the 95% isodose line volume to 3-beam proton plan, sparing surrounding organs, such as lung and chest wall. For chest wall, V30 is reduced from 21 cm{sup 3} (3 proton beams) to 11.5 cm{sup 3}, 12.9 cm{sup 3}, and 8.63 cm{sup 3} (P=.005) for Passive-Arc, IMPT-Arc, and Photon-VMAT, respectively. In the low-dose region, the mean lung dose and V20 of the ipsilateral lung are 5.01 Gy(relative biological effectiveness [RBE]), 4.38 Gy(RBE), 4.91 Gy(RBE), and 5.99 Gy(RBE) and 9.5%, 7.5%, 9.0%, and 10.0%, respectively, for 3-beam, Passive-Arc, IMPT-Arc, and Photon-VMAT, respectively. Conclusions: Stereotactic body radiation therapy with proton arc and Photon-VMAT generate significantly more conformal high-dose volumes than standard proton SBRT, without loss of coverage of the tumor and with significant sparing of nearby organs, such as chest wall. In addition

  17. Change of the NADPH depending superoxide producing and ferri hemoglobin reducing activities of cytochrome b558 from spleen cells and erythrocytes membranes induced by the radiation of different character

    International Nuclear Information System (INIS)

    Melkonyan, L.G.; Simonyan, R.M.; Simonyan, M.A.; Sekoyan, E.S.

    2009-01-01

    After the X radiation, UVA radiation and ultrasound radiation of new isoforms of cytochrome cyt b 5 58 from rats erythrocyte membranes - EM (cyt b 5 58III) and from spleen cell membranes (SCM) in vitro, as well as after the radiation of EM ex vivo, the suppression of both NADPH depending O 2 - producing and ferrihemoglobin (ferriHb)-reducing activities of cyt b 5 58 from EM and SCM in homogeneous (in solution) and heterogeneous phases (in EM and SCM) at various scopes takes place. These changes are associated with the destabilization of EM and SCM, conditioned by the change of the aggregation degree of these hemoproteins in EM and SCM, hemoproteins as a result of the influence of the hydrogen peroxide formed during radiolysis and photolysis of the water medium. After He-Ne laser radiation of the cyt b 5 58 from EM and SCM in vitro an increase of the NADPH depending O 2 - producing and ferriHb-reducing activities of the cyt b 5 58 from EM and SCM in homogenous and heterogeneous phases (in membranes) takes place. It is supposed that the suppression (by X-, UVA- and US-radiation) and the stimulation (by He-Ne laser radiation) of the immune system activity and the oxygen homeostasis are associated with the corresponding decrease and increase of the NADPH depending O 2 - producing and ferriHb-reducings activity of the new isoforms of cyt b 5 58 from EM and SCM in homogeneous and heterogeneous phases

  18. Efficacy of a Radiation Absorbing Shield in Reducing Dose to the Interventionalist During Peripheral Endovascular Procedures: A Single Centre Pilot Study

    International Nuclear Information System (INIS)

    Power, S.; Mirza, M.; Thakorlal, A.; Ganai, B.; Gavagan, L. D.; Given, M. F.; Lee, M. J.

    2015-01-01

    PurposeThis prospective pilot study was undertaken to evaluate the feasibility and effectiveness of using a radiation absorbing shield to reduce operator dose from scatter during lower limb endovascular procedures.Materials and MethodsA commercially available bismuth shield system (RADPAD) was used. Sixty consecutive patients undergoing lower limb angioplasty were included. Thirty procedures were performed without the RADPAD (control group) and thirty with the RADPAD (study group). Two separate methods were used to measure dose to a single operator. Thermoluminescent dosimeter (TLD) badges were used to measure hand, eye, and unshielded body dose. A direct dosimeter with digital readout was also used to measure eye and unshielded body dose. To allow for variation between control and study groups, dose per unit time was calculated.ResultsTLD results demonstrated a significant reduction in median body dose per unit time for the study group compared with controls (p = 0.001), corresponding to a mean dose reduction rate of 65 %. Median eye and hand dose per unit time were also reduced in the study group compared with control group, however, this was not statistically significant (p = 0.081 for eye, p = 0.628 for hand). Direct dosimeter readings also showed statistically significant reduction in median unshielded body dose rate for the study group compared with controls (p = 0.037). Eye dose rate was reduced for the study group but this was not statistically significant (p = 0.142).ConclusionInitial results are encouraging. Use of the shield resulted in a statistically significant reduction in unshielded dose to the operator’s body. Measured dose to the eye and hand of operator were also reduced but did not reach statistical significance in this pilot study

  19. Efficacy of a Radiation Absorbing Shield in Reducing Dose to the Interventionalist During Peripheral Endovascular Procedures: A Single Centre Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    Power, S.; Mirza, M.; Thakorlal, A.; Ganai, B.; Gavagan, L. D.; Given, M. F.; Lee, M. J., E-mail: mlee@rcsi.ie [Beaumont Hospital, Imaging and Interventional Radiology Department (Ireland)

    2015-06-15

    PurposeThis prospective pilot study was undertaken to evaluate the feasibility and effectiveness of using a radiation absorbing shield to reduce operator dose from scatter during lower limb endovascular procedures.Materials and MethodsA commercially available bismuth shield system (RADPAD) was used. Sixty consecutive patients undergoing lower limb angioplasty were included. Thirty procedures were performed without the RADPAD (control group) and thirty with the RADPAD (study group). Two separate methods were used to measure dose to a single operator. Thermoluminescent dosimeter (TLD) badges were used to measure hand, eye, and unshielded body dose. A direct dosimeter with digital readout was also used to measure eye and unshielded body dose. To allow for variation between control and study groups, dose per unit time was calculated.ResultsTLD results demonstrated a significant reduction in median body dose per unit time for the study group compared with controls (p = 0.001), corresponding to a mean dose reduction rate of 65 %. Median eye and hand dose per unit time were also reduced in the study group compared with control group, however, this was not statistically significant (p = 0.081 for eye, p = 0.628 for hand). Direct dosimeter readings also showed statistically significant reduction in median unshielded body dose rate for the study group compared with controls (p = 0.037). Eye dose rate was reduced for the study group but this was not statistically significant (p = 0.142).ConclusionInitial results are encouraging. Use of the shield resulted in a statistically significant reduction in unshielded dose to the operator’s body. Measured dose to the eye and hand of operator were also reduced but did not reach statistical significance in this pilot study.

  20. Efficacy of a radiation absorbing shield in reducing dose to the interventionalist during peripheral endovascular procedures: a single centre pilot study.

    Science.gov (United States)

    Power, S; Mirza, M; Thakorlal, A; Ganai, B; Gavagan, L D; Given, M F; Lee, M J

    2015-06-01

    This prospective pilot study was undertaken to evaluate the feasibility and effectiveness of using a radiation absorbing shield to reduce operator dose from scatter during lower limb endovascular procedures. A commercially available bismuth shield system (RADPAD) was used. Sixty consecutive patients undergoing lower limb angioplasty were included. Thirty procedures were performed without the RADPAD (control group) and thirty with the RADPAD (study group). Two separate methods were used to measure dose to a single operator. Thermoluminescent dosimeter (TLD) badges were used to measure hand, eye, and unshielded body dose. A direct dosimeter with digital readout was also used to measure eye and unshielded body dose. To allow for variation between control and study groups, dose per unit time was calculated. TLD results demonstrated a significant reduction in median body dose per unit time for the study group compared with controls (p = 0.001), corresponding to a mean dose reduction rate of 65 %. Median eye and hand dose per unit time were also reduced in the study group compared with control group, however, this was not statistically significant (p = 0.081 for eye, p = 0.628 for hand). Direct dosimeter readings also showed statistically significant reduction in median unshielded body dose rate for the study group compared with controls (p = 0.037). Eye dose rate was reduced for the study group but this was not statistically significant (p = 0.142). Initial results are encouraging. Use of the shield resulted in a statistically significant reduction in unshielded dose to the operator's body. Measured dose to the eye and hand of operator were also reduced but did not reach statistical significance in this pilot study.

  1. Pacific salmonines in the Great Lakes Basin

    Science.gov (United States)

    Claramunt, Randall M.; Madenjian, Charles P.; Clapp, David; Taylor, William W.; Lynch, Abigail J.; Léonard, Nancy J.

    2012-01-01

    Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing

  2. A history of presatellite investigations of the earth's radiation budget

    Science.gov (United States)

    Hunt, G. E.; Kandel, R.; Mecherikunnel, A. T.

    1986-01-01

    The history of radiation budget studies from the early twentieth century to the advent of the space age is reviewed. By the beginning of the 1960's, accurate radiative models had been developed capable of estimating the global and zonally averaged components of the radiation budget, though great uncertainty in the derived parameters existed due to inaccuracy of the data describing the physical parameters used in the model, associated with clouds, the solar radiation, and the gaseous atmospheric absorbers. Over the century, the planetary albedo estimates had reduced from 89 to 30 percent.

  3. Review: The Great Gatsby

    Directory of Open Access Journals (Sweden)

    Antonia de Jesus Sales

    2016-08-01

    Full Text Available A presente resenha busca discutir a tradução de The Great Gatsby para o contexto brasileiro. Diversas traduções foram feitas, em diversas épocas e com repercussão positiva no contexto brasileiro. Para o presente estudo, foi observada a tradução de Vanessa Bárbara, de 2011. Nesse sentido, o aspecto biográficos do autor e a forma como se apresentam os personagens na obra são fatores de cotejamento na obra original e na tradução brasileira. Francis Scott Key Fitzgerald (1896 – 1940 é famoso por ter em suas obras traços biográficos, algo que certamente influencia o leitor que adentra a sua obra. Quanto à recepção de O Grande Gatsby no contexto brasileiro, há que se considerar que O Grande Gatsby teve diversas traduções no Brasil. Depois dessa tradução de Vanessa Bárbara, em 2011, outras três vieram em 2013, juntamente com o filme. Há que considerar os aspectos comerciais embutidos nessas traduções e que muito corroboram para o resultado final. Prova disso são as capas, que são sempre diferenciadas em cada edição lançada. O tradutor nem sempre pode opinar sobre questões como estas. A tradução, a meu ver, é uma obra de qualidade, visto que a tradutora buscou ser fiel, sem dificultar a interpretação da obra para o leitor.

  4. Review: The Great Gatsby

    Directory of Open Access Journals (Sweden)

    Antonia de Jesus Sales

    2016-05-01

    Full Text Available A presente resenha busca discutir a tradução de The Great Gatsby para o contexto brasileiro. Diversas traduções foram feitas, em diversas épocas e com repercussão positiva no contexto brasileiro. Para o presente estudo, foi observada a tradução de Vanessa Bárbara, de 2011. Nesse sentido, o aspecto biográficos do autor e a forma como se apresentam os personagens na obra são fatores de cotejamento na obra original e na tradução brasileira. Francis Scott Key Fitzgerald (1896 – 1940 é famoso por ter em suas obras traços biográficos, algo que certamente influencia o leitor que adentra a sua obra. Quanto à recepção de O Grande Gatsby no contexto brasileiro, há que se considerar que O Grande Gatsby teve diversas traduções no Brasil. Depois dessa tradução de Vanessa Bárbara, em 2011, outras três vieram em 2013, juntamente com o filme. Há que considerar os aspectos comerciais embutidos nessas traduções e que muito corroboram para o resultado final. Prova disso são as capas, que são sempre diferenciadas em cada edição lançada. O tradutor nem sempre pode opinar sobre questões como estas. A tradução, a meu ver, é uma obra de qualidade, visto que a tradutora buscou ser fiel, sem dificultar a interpretação da obra para o leitor.

  5. Prescreening based on the presence of CT-scan abnormalities and biomarkers (KL-6 and SP-D may reduce severe radiation pneumonitis after stereotactic radiotherapy

    Directory of Open Access Journals (Sweden)

    Wakui Reiko

    2010-05-01

    Full Text Available Abstract Purpose To determine the risk factors of severe radiation pneumonitis (RP after stereotactic body radiation therapy (SBRT for primary or secondary lung tumors. Materials and methods From January 2003 to March 2009, SBRT was performed on 117 patients (32 patients before 2005 and 85 patients after 2006 with lung tumors (primary = 74 patients and metastatic/recurrent = 43 patients in our institution. In the current study, the results on cases with severe RP (grades 4-5 were evaluated. Serum Krebs von den Lungen-6 (KL-6 and serum Surfactant protein-D (SP-D were used to predict the incidence of RP. A shadow of interstitial pneumonitis (IP on the CT image before performing SBRT was also used as an indicator for RP. Since 2006, patients have been prescreened for biological markers (KL-6 & SP-D as well as checking for an IP-shadow in CT. Results Grades 4-5 RP was observed in nine patients (7.7% after SBRT and seven of these cases (6.0% were grade 5 in our institution. A correlation was found between the incidence of RP and higher serum KL-6 & SP-D levels. IP-shadow in patient's CT was also found to correlate well with the severe RP. Severe RP was reduced from 18.8% before 2005 to 3.5% after 2006 (p = 0.042. There was no correlation between the dose volume histogram parameters and these severe RP patients. Conclusion Patients presenting with an IP shadow in the CT and a high value of the serum KL-6 & SP-D before SBRT treatment developed severe radiation pneumonitis at a high rate. The reduction of RP incidence in patients treated after 2006 may have been attributed to prescreening of the patients. Therefore, pre-screening before SBRT for an IP shadow in CT and serum KL-6 & SP-D is recommended in the management and treatment of patients with primary or secondary lung tumors.

  6. Great Lakes Environmental Database (GLENDA)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Great Lakes Environmental Database (GLENDA) houses environmental data on a wide variety of constituents in water, biota, sediment, and air in the Great Lakes area.

  7. 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.

  8. Radiation protection

    International Nuclear Information System (INIS)

    Jain, Aman; Sharma, Shivam; Parasher, Abhishek

    2014-01-01

    Radiation dose measurement, field of radiobiology, is considered to be critical factor for optimizing radiation protection to the health care practitioners, patients and the public. This lead to equipment that has dose - area product meters permanently installed. In many countries and even institution, the range of equipment is vast and with the opportunity for radiation protection and dose recording varies considerably. Practitioners must move with the changed demands of radiation protection but in many cases without assistance of modern advancements in technology Keeping the three basic safety measures Time, Dose and Shielding we can say 'Optimum dose is safe dose' instead of 'No dose is safe dose'. The purpose enclosed within the title 'Radiation Protection'. The use of radiation is expanding widely everyday around the world and crossing boundaries of medical imaging, diagnostic and. The way to get the ''As low as reasonably achievable' is only achievable by using methodology of radiation protection and to bring the concern of general public and practitioners over the hazards of un-necessary radiation dose. Three basic principles of radiation protection are time, distance and shielding. By minimizing the exposure time increasing the distance and including the shielding we can reduce the optimum range of dose. The ability of shielding material to attenuate radiation is generally given as half value layer. This is the thickness of the material which will reduce the amount of radiation by 50%. Lab coat and gloves must be worn when handling radioactive material or when working in a labeled radiation work area. Safety glasses or other appropriate splash shields should be used when handling radioactive material. 1. Reached to low dose level to occupational workers, public as per prescribed dose limit. 2. By mean of ALARA principle we achieved the protection from radiation besides us using the radiation for our benefit

  9. 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.

  10. Utility of the inspiratory phase in high-resolution computed tomography evaluations of pediatric patients with bronchiolitis obliterans after allogeneic bone marrow transplant: reducing patient radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Togni Filho, Paulo Henrique; Casagrande, Joao Luiz Marin; Lederman, Henrique Manoel, E-mail: paulotognifilho@gmail.com [Universidade Federal de Sao Paulo (EPM/UNIFESP), Sao Paulo, SP (Brazil). Escola Paulista de Medicina. Dept. of Diagnostico por Imagem; Universidade de Sao Paulo (InRad/HC/FMUSP), Sao Paulo, SP (Brazil). Hospital das Clinicas. Instituto de Radiologia

    2017-03-15

    Objective: To evaluate the utility of the inspiratory phase in high-resolution computed tomography (HRCT) of the chest for the diagnosis of post-bone marrow transplantation bronchiolitis obliterans. Materials and Methods: This was a retrospective, observational, cross-sectional study. We selected patients of either gender who underwent bone marrow transplantation and chest HRCT between March 1, 2002 and December 12, 2014. Ages ranged from 3 months to 20.7 years. We included all examinations in which the HRCT was performed appropriately. The examinations were read by two radiologists, one with extensive experience in pediatric radiology and another in the third year of residency, who determined the presence or absence of the following imaging features: air trapping, bronchiectasis, alveolar opacities, nodules, and atelectasis. Results: A total of 222 examinations were evaluated (mean, 5.4 ± 4.5 examinations per patient). The expiratory phase findings were comparable to those obtained in the inspiratory phase, except in one patient, in whom a small uncharacteristic nodule was identified only in the inspiratory phase. Air trapping was identified in a larger number of scans in the expiratory phase than in the inspiratory phase, as was atelectasis, although the difference was statistically significant only for air trapping. Conclusion: In children being evaluated for post-bone marrow transplantation bronchiolitis obliterans, the inspiratory phase can be excluded from the chest HRCT protocol, thus reducing by half the radiation exposure in this population. (author)

  11. Reducing radiation dose in the diagnosis of pulmonary embolism using adaptive statistical iterative reconstruction and lower tube potential in computed tomography

    International Nuclear Information System (INIS)

    Kaul, David; Grupp, Ulrich; Kahn, Johannes; Wiener, Edzard; Hamm, Bernd; Streitparth, Florian; Ghadjar, Pirus

    2014-01-01

    To assess the impact of ASIR (adaptive statistical iterative reconstruction) and lower tube potential on dose reduction and image quality in chest computed tomography angiographies (CTAs) of patients with pulmonary embolism. CT data from 44 patients with pulmonary embolism were acquired using different protocols - Group A: 120 kV, filtered back projection, n = 12; Group B: 120 kV, 40 % ASIR, n = 12; Group C: 100 kV, 40 % ASIR, n = 12 and Group D: 80 kV, 40 % ASIR, n = 8. Normalised effective dose was calculated; image quality was assessed quantitatively and qualitatively. Normalised effective dose in Group B was 33.8 % lower than in Group A (p = 0.014) and 54.4 % lower in Group C than in Group A (p < 0.001). Group A, B and C did not show significant differences in qualitative or quantitative analysis of image quality. Group D showed significantly higher noise levels in qualitative and quantitative analysis, significantly more artefacts and decreased overall diagnosability. Best results, considering dose reduction and image quality, were achieved in Group C. The combination of ASIR and lower tube potential is an option to reduce radiation without significant worsening of image quality in the diagnosis of pulmonary embolism. (orig.)

  12. Reducing radiation dose in the diagnosis of pulmonary embolism using adaptive statistical iterative reconstruction and lower tube potential in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kaul, David [Campus Virchow-Klinikum, Department of Radiation Oncology, Charite School of Medicine and University Hospital, Berlin (Germany); Charite School of Medicine and University Hospital, Department of Radiology, Berlin (Germany); Grupp, Ulrich; Kahn, Johannes; Wiener, Edzard; Hamm, Bernd; Streitparth, Florian [Charite School of Medicine and University Hospital, Department of Radiology, Berlin (Germany); Ghadjar, Pirus [Campus Virchow-Klinikum, Department of Radiation Oncology, Charite School of Medicine and University Hospital, Berlin (Germany)

    2014-11-15

    To assess the impact of ASIR (adaptive statistical iterative reconstruction) and lower tube potential on dose reduction and image quality in chest computed tomography angiographies (CTAs) of patients with pulmonary embolism. CT data from 44 patients with pulmonary embolism were acquired using different protocols - Group A: 120 kV, filtered back projection, n = 12; Group B: 120 kV, 40 % ASIR, n = 12; Group C: 100 kV, 40 % ASIR, n = 12 and Group D: 80 kV, 40 % ASIR, n = 8. Normalised effective dose was calculated; image quality was assessed quantitatively and qualitatively. Normalised effective dose in Group B was 33.8 % lower than in Group A (p = 0.014) and 54.4 % lower in Group C than in Group A (p < 0.001). Group A, B and C did not show significant differences in qualitative or quantitative analysis of image quality. Group D showed significantly higher noise levels in qualitative and quantitative analysis, significantly more artefacts and decreased overall diagnosability. Best results, considering dose reduction and image quality, were achieved in Group C. The combination of ASIR and lower tube potential is an option to reduce radiation without significant worsening of image quality in the diagnosis of pulmonary embolism. (orig.)

  13. Utility of the inspiratory phase in high-resolution computed tomography evaluations of pediatric patients with bronchiolitis obliterans after allogeneic bone marrow transplant: reducing patient radiation exposure

    International Nuclear Information System (INIS)

    Togni Filho, Paulo Henrique; Casagrande, Joao Luiz Marin; Lederman, Henrique Manoel; Universidade de Sao Paulo

    2017-01-01

    Objective: To evaluate the utility of the inspiratory phase in high-resolution computed tomography (HRCT) of the chest for the diagnosis of post-bone marrow transplantation bronchiolitis obliterans. Materials and Methods: This was a retrospective, observational, cross-sectional study. We selected patients of either gender who underwent bone marrow transplantation and chest HRCT between March 1, 2002 and December 12, 2014. Ages ranged from 3 months to 20.7 years. We included all examinations in which the HRCT was performed appropriately. The examinations were read by two radiologists, one with extensive experience in pediatric radiology and another in the third year of residency, who determined the presence or absence of the following imaging features: air trapping, bronchiectasis, alveolar opacities, nodules, and atelectasis. Results: A total of 222 examinations were evaluated (mean, 5.4 ± 4.5 examinations per patient). The expiratory phase findings were comparable to those obtained in the inspiratory phase, except in one patient, in whom a small uncharacteristic nodule was identified only in the inspiratory phase. Air trapping was identified in a larger number of scans in the expiratory phase than in the inspiratory phase, as was atelectasis, although the difference was statistically significant only for air trapping. Conclusion: In children being evaluated for post-bone marrow transplantation bronchiolitis obliterans, the inspiratory phase can be excluded from the chest HRCT protocol, thus reducing by half the radiation exposure in this population. (author)

  14. Lateral rectal shielding reduces late rectal morbidity after high dose three-dimensional conformal radiation therapy for clinically localized prostate cancer: further evidence for a dose effect

    Energy Technology Data Exchange (ETDEWEB)

    Lee, W Robert; Hanks, Gerald E; Hanlon, Alexandra; Schultheiss, Timothy E

    1995-07-01

    Purpose: Using conventional treatment methods for the treatment of clinically localized prostate cancer central axis doses must be limited to 65-70 Gy to prevent significant damage to nearby normal tissues. A fundamental hypothesis of three-dimensional conformal radiation therapy (3DCRT) is that, by defining the target organ(s) accurately in three dimensions, it is possible to deliver higher doses to the target without a significant increase in normal tissue complications. This study examines whether this hypothesis holds true and whether a simple modification of treatment technique can reduce the incidence of late rectal morbidity in patients with prostate cancer treated with 3DCRT to minimum planning target volume (PTV) doses of 71-75 Gy. Materials and Methods: 257 patients with clinically localized prostate cancer completed 3DCRT by December 31, 1993 and received a minimum PTV dose of 71-75 Gy. The median follow-up time was 22 months (range 4-67 months) and 98% of patients had followup of longer than 12 months. The calculated dose at the center of the prostate was <74 Gy in 19 patients, 74-76 Gy in 206 patients and >76 Gy in 32 patients. Late rectal morbidity was graded according to the LENT scoring system. Eighty-eight consecutive patients were treated with a rectal block added to the lateral fields. In these patients the posterior margin from the prostate to the block edge was reduced from the standard 15 mm to 7.5 mm for the final 10 Gy which reduced the dose to portions of the anterior rectal wall by approximately 4-5 Gy. Estimates of rates for rectal morbidity were determined by Kaplan-Meier actuarial analyses. Differences in morbidity percentages were evaluated by the Pearson chi square test. Results: Grade 2-3 rectal morbidity developed in 46 of 257 patients (18%) and in the majority of cases consisted of rectal bleeding. No patient has developed grade 4 or 5 rectal morbidity. The actuarial rate of grade 2-3 morbidity is 22% at 24 months and the median

  15. Great red spot dependence on solar activity

    International Nuclear Information System (INIS)

    Schatten, K.H.

    1979-01-01

    A new inquiry has been made into the question of whether Jupiter's Great Red Spot shows a solar activity dependence. From 1892 to 1947 a clear correlation was present. A dearth of sightings in the seventeenth century, along with the Maunder Minimum, further supports the relation. An anticorrelation, however, from l948 to l967 removed support for such an effect. The old observations have reexamined and recent observations have also been studied. The author reexamines this difficult question and suggests a possible physical mechanism for a Sun-Jovian weather relation. Prinn and Lewis' conversion reaction of Phosphine gas to triclinic red phosphorous crystals is a reaction dependent upon solar radiation. It may explain the dependence found, as well as the striking appearance of the Great Red Spot in the UV

  16. Navvus FFR to reduce CONTRAst, Cost and radiaTion (CONTRACT); insights from a single-centre clinical and economical evaluation with the RXi Rapid-Exchange FFR device

    NARCIS (Netherlands)

    Masdjedi, K.; Mieghem, N.M. van; Diletti, R.; Geuns, R.J.M. van; Jaegere, P. De; Regar, E.; Zijlstra, F.; Domburg, R.T. van; Daemen, J.

    2017-01-01

    OBJECTIVES: To assess whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention.

  17. Efficacy of the RADPAD Protection Drape in Reducing Operators' Radiation Exposure in the Catheterization Laboratory: A Sham-Controlled Randomized Trial

    NARCIS (Netherlands)

    Vlastra, Wieneke; Delewi, Ronak; Sjauw, Krischan D.; Beijk, Marcel A.; Claessen, Bimmer E.; Streekstra, Geert J.; Bekker, Robbert J.; van Hattum, Juliette C.; Wykrzykowska, Joanna J.; Vis, Marije M.; Koch, Karel T.; de Winter, Robbert J.; Piek, Jan J.; Henriques, José P. S.

    2017-01-01

    Background Interventional cardiologists are increasingly exposed to radiation-induced diseases like cataract and the stochastic risk of left-sided brain tumors. The RADPAD is a sterile, disposable, lead-free shield placed on the patient with the aim to minimize operator-received scatter radiation.

  18. The Great London Smog of 1952.

    Science.gov (United States)

    Polivka, Barbara J

    2018-04-01

    : The Great London Smog of December 1952 lasted five days and killed up to 12,000 people. The smog developed primarily because of extensive burning of high-sulfur coal. The health effects were both immediate and long lasting, with a recent study revealing an increased likelihood of childhood asthma development in those exposed to the Great Smog while in utero or during their first year of life. Subsequent pollution legislation-including the U.S. Clean Air Act and its amendments-have demonstrably reduced air pollution and positively impacted health outcomes. With poor air quality events like the Great Smog continuing to occur today, nurses need to be aware of the impact such environmental disasters can have on human health.

  19. ["Great jobs"-also in psychiatry?].

    Science.gov (United States)

    Spiessl, H; Hübner-Liebermann, B

    2003-09-01

    Against the background of a beginning shortage of psychiatrists, results from interviews with 112 employees of an automotive company with the topic "Great Job" are presented to discuss their relevance to psychiatry. The interviews were analysed by means of a qualitative content analysis. Most employees assigned importance to great pay, constructive collaboration with colleagues, and work appealing to personal interests. Further statements particularly relevant to psychiatry were: successful career, flexible working hours, manageable job, work-life balance, well-founded training, no bureaucracy within the company, and personal status in society. The well-known economic restrictions in health care and the still negative attitude towards psychiatry currently reduce the attraction of psychiatry as a profession. From the viewpoint of personnel management, the attractors of a great job revealed in this study are proposed as important clues for the recruitment of medical students for psychiatry and the development of psychiatric staff.

  20. Nonionizing radiation and health

    International Nuclear Information System (INIS)

    Suess, M.J.

    1985-01-01

    While a great deal of work has been done by international bodies to establish permissible levels for ionizing radiation, much less attention has been paid to the nonionizing forms of radiation and their possible health effects. Taking into account that equipment producing such radiation is now widely used both in the house and in industry, the paper presents the possible health effects of ultraviolet, visible, laser, infrared and microwave radiation, of electric and magnetic fields and of the ultrasound waves

  1. Intraoperative Radiation Therapy Reduces Local Recurrence Rates in Patients With Microscopically Involved Circumferential Resection Margins After Resection of Locally Advanced Rectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Alberda, Wijnand J.; Verhoef, Cornelis [Department of Surgery, Division of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Nuyttens, Joost J. [Department of Radiotherapy, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Meerten, Esther van [Department of Medical Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Rothbarth, Joost [Department of Surgery, Division of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands); Wilt, Johannes H.W. de [Department of Surgery, Division of Surgical Oncology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Burger, Jacobus W.A., E-mail: j.burger@erasmusmc.nl [Department of Surgery, Division of Surgical Oncology, Erasmus MC Cancer Institute, Rotterdam (Netherlands)

    2014-04-01

    Purpose: Intraoperative radiation therapy (IORT) is advocated by some for patients with locally advanced rectal cancer (LARC) who have involved or narrow circumferential resection margins (CRM) after rectal surgery. This study evaluates the potentially beneficial effect of IORT on local control. Methods and Materials: All surgically treated patients with LARC treated in a tertiary referral center between 1996 and 2012 were analyzed retrospectively. The outcome in patients treated with IORT with a clear but narrow CRM (≤2 mm) or a microscopically involved CRM was compared with the outcome in patients who were not treated with IORT. Results: A total of 409 patients underwent resection of LARC, and 95 patients (23%) had a CRM ≤ 2 mm. Four patients were excluded from further analysis because of a macroscopically involved resection margin. In 43 patients with clear but narrow CRMs, there was no difference in the cumulative 5-year local recurrence-free survival of patients treated with (n=21) or without (n=22) IORT (70% vs 79%, P=.63). In 48 patients with a microscopically involved CRM, there was a significant difference in the cumulative 5-year local recurrence-free survival in favor of the patients treated with IORT (n=31) compared with patients treated without IORT (n=17) (84 vs 41%, P=.01). Multivariable analysis confirmed that IORT was independently associated with a decreased local recurrence rate (hazard ratio 0.24, 95% confidence interval 0.07-0.86). There was no significant difference in complication rate of patients treated with or without IORT (65% vs 52%, P=.18) Conclusion: The current study suggests that IORT reduces local recurrence rates in patients with LARC with a microscopically involved CRM.

  2. What Caused the Great Depression?

    Science.gov (United States)

    Caldwell, Jean; O'Driscoll, Timothy G.

    2007-01-01

    Economists and historians have struggled for almost 80 years to account for the American Great Depression, which began in 1929 and lasted until the early years of World War II. In this article, the authors discuss three major schools of thought on the causes of the Great Depression and the long failure of the American economy to return to full…

  3. Radiation Synthesis of Nanoparticles

    International Nuclear Information System (INIS)

    Khairul Zaman Mohd Dahlan; Jamaliah Sharif; Nik Ghazali Nik Salleh; Dahlan Mohd; Kamaruddin Hashim

    2011-01-01

    Radiation processing of nano materials is one of the many applications of ionising radiation. It has the advantages of cold process, fast, homogeneous and clean processing without using chemicals, heat and no release of any volatile organic compounds. Hence, radiation processing can be categorised as a green process. The applications of ionising radiation for materials processing are well established and commercialized by way of crosslinking, grafting, curing and degradation. However, the materials use, condition of processing and the end products varies and radiation processing is continue to be developed for various applications in industry, agriculture, health care and environment. The new and emerging development of nano materials has also being incorporated in radiation processing whereby we can see the convergence of radiation and nano technology, to take advantages of the inherent properties of nano size particles. Nowadays many works are being carried out on radiation processing of nano materials. The incorporation of such nanoparticles in polymeric materials will render specific properties that find several advantages compare to conventional composites such as increase heat resistant, improve abrasion and scratch resistant and enhance mechanical properties. In recent years, polymer/clay nano composites has attracted the interest of industry because of its major improvements in physical and mechanical properties, heat stability, reduce flammability and provide enhanced barrier properties at low clay contents. In many applications, crosslinking of polymer matrix is necessary that can further improved the mechanical and physical properties of the composites. Similar research has been extended to electron beam crosslinking of electromagnetic nano composites which comprise of high volume fraction of inorganic fillers in elastomeric matrix. The effect of radiation on inorganic fillers is believed to has influence on the overall radiation crosslinking of the

  4. Cosmic Reason of Great Glaciation

    Science.gov (United States)

    Bagrov, Alexander; Murtazov, Andrey

    The origin of long-time and global glaciations in the past of our planet, which have been named «great», is still not clear. Both the advance of glaciers and their subsequent melting must be connected with some energy consuming processes. There is a powerful energy source permanently functioning throughout the Earth’s history - the solar radiation. The equality of the incoming shortwave solar energy and the transformed long-wave energy emitted by the Earth provides for the whole ecosphere’s sustainable evolution. Great glaciations might be caused by space body falls into the world oceans. If the body is large enough, it can stir waters down to the bottom. The world waters are part of the global heat transfer from the planet’s equator to its poles (nowadays, mostly to the North Pole). The mixing of the bottom and surface waters breaks the circulation of flows and they stop. The termination of heat transfer to the poles will result in an icecap at high latitudes which in its turn will decrease the total solar heat inflow to the planet and shift the pole ice boarder to the equator. This positive feedback may last long and result in long-time glaciations. The oceanic currents will remain only near the equator. The factor obstructing the global cooling is the greenhouse effect. Volcanic eruptions supply a lot of carbon dioxide into the atmosphere. When due to the increased albedo the planet receives less solar heat, plants bind less carbon oxide into biomass and more of it retains in the atmosphere. Therefore, the outflow of heat from the planet decreases and glaciations does not involve the whole planet. The balance established between the heat inflow and heat losses is unstable. Any imbalance acts as a positive feed-back factor. If the volcanic activity grows, the inflow of the carbon dioxide into the atmosphere will cause its heating-up (plants will fail to reproduce themselves quickly enough to utilize the carbonic acid). The temperature growth will lead to

  5. Altmetric: 165More detailArticle | OPENClimate change-induced increases in precipitation are reducing the potential for solar ultraviolet radiation to inactivate pathogens in surface waters

    Science.gov (United States)

    Climate change is accelerating the release of dissolved organic matter (DOM) to inland and coastal waters through increases in precipitation, thawing of permafrost, and changes in vegetation. Our modeling approach suggests that the selective absorption of ultraviolet radiation (U...

  6. Radiation detector

    International Nuclear Information System (INIS)

    Gillies, W.

    1980-01-01

    The radiation detector for measuring e.g. a neutron flux consists of a central emitter, an insulating shell arranged around it, and a tube-shaped collector enclosing both. The emitter itself is composed of a great number of stranded, spiral wires of small diameter giving a defined flexibility to the detector. For emitter material Pt, Rh, V, Co, Ce, Os or Ta may be used. (DG) [de

  7. 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.

  8. Simultaneous whole-body PET-MRI in pediatric oncology. More than just reducing radiation?; Simultane Ganzkoerper-PET-MRT in der paediatrischen Onkologie. Mehr als nur Strahlenersparnis

    Energy Technology Data Exchange (ETDEWEB)

    Gatidis, S.; Gueckel, B.; Schaefer, J.F. [Universitaet Tuebingen, Radiologische Klinik, Diagnostische und Interventionelle Radiologie, Tuebingen (Germany); Fougere, C. la [Universitaet Tuebingen, Radiologische Klinik, Nuklearmedizin, Tuebingen (Germany); Schmitt, J. [Universitaet Tuebingen, Abteilung fuer Praeklinische Bildgebung und Radiopharmazie, Werner Siemens Imaging Center, Tuebingen (Germany)

    2016-07-15

    Diagnostic imaging plays an essential role in pediatric oncology with regard to diagnosis, therapy-planning, and the follow-up of solid tumors. The current imaging standard in pediatric oncology includes a variety of radiological and nuclear medicine imaging modalities depending on the specific tumor entity. The introduction of combined simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) has opened up new diagnostic options in pediatric oncology. This novel modality combines the excellent anatomical accuracy of MRI with the metabolic information of PET. In initial clinical studies, the technical feasibility and possible diagnostic advantages of combined PET-MRI have been in comparison with alternative imaging techniques. It was shown that a reduction in radiation exposure of up to 70 % is achievable compared with PET-CT. Furthermore, it has been shown that the number of imaging studies necessary can be markedly reduced using combined PET-MRI. Owing to its limited availability, combined PET-MRI is currently not used as a routine procedure. However, this new modality has the potential to become the imaging reference standard in pediatric oncology in the future. This review article summarizes the central aspects of pediatric oncological PET-MRI based on existing literature. Typical pediatric oncological PET-MRI cases are also presented. (orig.) [German] Die bildgebende Diagnostik spielt in der paediatrischen Onkologie eine zentrale Rolle fuer die Diagnose, die Therapieplanung und die Nachsorge solider Tumoren. Der aktuell bildgebende Standard in der paediatrischen Onkologie sieht - abhaengig von der vorliegenden Tumorentitaet - eine Kombination mehrerer radiologischer und nuklearmedizinischer Verfahren vor. Die Einfuehrung der simultanen Positronenemissionstomographie(PET)-Magnetresonanztomographie (MRT) hat neuartige Moeglichkeiten der Diagnostik in der paediatrischen Onkologie eroeffnet. Dabei kombiniert dieses neue Verfahren die

  9. Great Lakes Environmental Research Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — NOAA-GLERL and its partners conduct innovative research on the dynamic environments and ecosystems of the Great Lakes and coastal regions to provide information for...

  10. What Caused the Great Recession?

    OpenAIRE

    Homburg, Stefan

    2014-01-01

    This paper examines five possible explanations for the Great Recession of 2008 and 2009, using data for the United States and the eurozone. Of these five hypotheses, four are not supported by the data, while the fifth appears reasonable.

  11. Arthroscopy of the great toe

    NARCIS (Netherlands)

    Frey, C.; van Dijk, C. N.

    1999-01-01

    The few available reports of arthroscopic treatment of the first MTP joint in the literature indicate favorable outcome. However, arthroscopy of the great toe is an advanced technique and should only be undertaken by experienced surgeons

  12. The Sixth Great Mass Extinction

    Science.gov (United States)

    Wagler, Ron

    2012-01-01

    Five past great mass extinctions have occurred during Earth's history. Humanity is currently in the midst of a sixth, human-induced great mass extinction of plant and animal life (e.g., Alroy 2008; Jackson 2008; Lewis 2006; McDaniel and Borton 2002; Rockstrom et al. 2009; Rohr et al. 2008; Steffen, Crutzen, and McNeill 2007; Thomas et al. 2004;…

  13. Doses of Coronary Study in 64 Channel Multi-Detector Computed Tomography : Reduced Radiation Dose According to Varity of Examnination Protocols

    International Nuclear Information System (INIS)

    Kim, Moon Chan

    2009-01-01

    To compare radiation dose for coronary CT angiography (CTA) obtained with 6 examination protocols such as a retrospectively ECG gated helical scan, a prospectively ECG gated sequential scan, low kVp technique, and cardiac dose modulation technique. Coronary CTA was performed by using 6 current clinical protocols to evaluate effective dose and organ dose in primary beam area with anthropomorphic female phantom and glass dosimetric system in 64 channel multi-detector CT. After acquiring topograms of frontal and lateral projection with 80 kVp and 10 mA, main coronary scan was done with 0.35 sec tube rotation time, 40 mm collimation (0.625 mm x 64 ea), small scan field of view (32 cm diameter), 105 mm scan length. Heart beat rate of phantom was maintained 60 bpm in ECG gating. In constant mAs technique 120 kVp, 600 mA was used, and 100 kVp for low kVp technique. In a retrospectively ECG gated helical CT technique 0.22 pitch was used, peak mA (600 mA) was adopted in range of 40-80% of R-R interval and 120 mA (80% reduction) in others with cardiac dose modulation. And 210 mAs was used without cardiac dose modulation. In a prospectively ECG gated sequential CT technique data were acquired at 75% R-R interval (middle diastolic phase in cardiac cycle), and 120 msec additional padding of the tube-on time was used. For effective dose calculation region specific conversion factor of dose length product in thorax was used, which was recommended by EUR 16262. The mean effective dose for conventional coronary CTA without cardiac dose modulation in a retrospectively ECG gated helical scan was 17.8 mSv, and mean organ dose of heart was 103.8 mGy. With low kVp and cardiac dose modulation the mean effective dose showed 54.5% reduction, and heart dose showed 52.3% reduction, compared with that of conventional coronary CTA. And at the sequential scan(SnapShot pulse mode) under prospective ECG gating the mean effective dose was 4.9 mSv, this represents an 72.5% reduction compared with

  14. Effect of gamma radiation on the growth of botryodiplodia theobromae and on rot development in banana fruits

    International Nuclear Information System (INIS)

    Mostafa, I.Y.; El-Ashmawi, A.M.; Fahim, M.M.; Kararah, M.A.

    1984-01-01

    Radiosensitivity of Botryodiplodia theobromae Pat. increased with the increase in doses of gamma radiation. Young cultures (7 days old) were less sensitive to radiation than old ones (48 days); lethal doses being 800 and 600 Krad respectively. Rot development was greatly reduced when inoculated banana fruits were exposed to 300 Krad. Disease development was checked for 10 days in inoculated fruits exposed to 400 Krad. The combined treatment of 200 p.p.m. T B Z and 100 or 200 Krad gamma radiation was more effective in reducing disease incidence than either treatments alone. No deleterious effects occurred in banana fruits that were irradiated with the low doses of gamma radiation

  15. Synchrotron radiation

    International Nuclear Information System (INIS)

    Knotek, M.L.

    1987-01-01

    Synchrotron radiation has had a revolutionary effect on a broad range of scientific studies, from physics, chemistry and metallurgy to biology, medicine and geoscience. The situation during the last decade has been one of very rapid growth, there is a great vitality to the field and a capability has been given to a very broad range of scientific disciplines which was undreamed of just a decade or so ago. Here we will discuss some of the properties of synchrotron radiation that makes it so interesting and something of the sources in existence today including the National Synchrotron Light Source (NSLS). The NSLS is one of the new facilities built specifically for synchrotron radiation research and the model that was developed there for involvement of the scientific community is a good one which provides some good lessons for these facilities and others

  16. Transposition of the great arteries

    Directory of Open Access Journals (Sweden)

    Castela Eduardo

    2008-10-01

    Full Text Available Abstract Transposition of the great arteries (TGA, also referred to as complete transposition, is a congenital cardiac malformation characterised by atrioventricular concordance and ventriculoarterial (VA discordance. The incidence is estimated at 1 in 3,500–5,000 live births, with a male-to-female ratio 1.5 to 3.2:1. In 50% of cases, the VA discordance is an isolated finding. In 10% of cases, TGA is associated with noncardiac malformations. The association with other cardiac malformations such as ventricular septal defect (VSD and left ventricular outflow tract obstruction is frequent and dictates timing and clinical presentation, which consists of cyanosis with or without congestive heart failure. The onset and severity depend on anatomical and functional variants that influence the degree of mixing between the two circulations. If no obstructive lesions are present and there is a large VSD, cyanosis may go undetected and only be perceived during episodes of crying or agitation. In these cases, signs of congestive heart failure prevail. The exact aetiology remains unknown. Some associated risk factors (gestational diabetes mellitus, maternal exposure to rodenticides and herbicides, maternal use of antiepileptic drugs have been postulated. Mutations in growth differentiation factor-1 gene, the thyroid hormone receptor-associated protein-2 gene and the gene encoding the cryptic protein have been shown implicated in discordant VA connections, but they explain only a small minority of TGA cases. The diagnosis is confirmed by echocardiography, which also provides the morphological details required for future surgical management. Prenatal diagnosis by foetal echocardiography is possible and desirable, as it may improve the early neonatal management and reduce morbidity and mortality. Differential diagnosis includes other causes of central neonatal cyanosis. Palliative treatment with prostaglandin E1 and balloon atrial septostomy are usually

  17. Hospital Capital Investment During the Great Recession.

    Science.gov (United States)

    Choi, Sung

    2017-01-01

    Hospital capital investment is important for acquiring and maintaining technology and equipment needed to provide health care. Reduction in capital investment by a hospital has negative implications for patient outcomes. Most hospitals rely on debt and internal cash flow to fund capital investment. The great recession may have made it difficult for hospitals to borrow, thus reducing their capital investment. I investigated the impact of the great recession on capital investment made by California hospitals. Modeling how hospital capital investment may have been liquidity constrained during the recession is a novel contribution to the literature. I estimated the model with California Office of Statewide Health Planning and Development data and system generalized method of moments. Findings suggest that not-for-profit and public hospitals were liquidity constrained during the recession. Comparing the changes in hospital capital investment between 2006 and 2009 showed that hospitals used cash flow to increase capital investment by $2.45 million, other things equal.

  18. Hospital Capital Investment During the Great Recession

    Science.gov (United States)

    Choi, Sung

    2017-01-01

    Hospital capital investment is important for acquiring and maintaining technology and equipment needed to provide health care. Reduction in capital investment by a hospital has negative implications for patient outcomes. Most hospitals rely on debt and internal cash flow to fund capital investment. The great recession may have made it difficult for hospitals to borrow, thus reducing their capital investment. I investigated the impact of the great recession on capital investment made by California hospitals. Modeling how hospital capital investment may have been liquidity constrained during the recession is a novel contribution to the literature. I estimated the model with California Office of Statewide Health Planning and Development data and system generalized method of moments. Findings suggest that not-for-profit and public hospitals were liquidity constrained during the recession. Comparing the changes in hospital capital investment between 2006 and 2009 showed that hospitals used cash flow to increase capital investment by $2.45 million, other things equal. PMID:28617202

  19. New sources of radiation

    International Nuclear Information System (INIS)

    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

  20. Effectiveness and limitations of parameter tuning in reducing biases of top-of-atmosphere radiation and clouds in MIROC version 5

    Science.gov (United States)

    Ogura, Tomoo; Shiogama, Hideo; Watanabe, Masahiro; Yoshimori, Masakazu; Yokohata, Tokuta; Annan, James D.; Hargreaves, Julia C.; Ushigami, Naoto; Hirota, Kazuya; Someya, Yu; Kamae, Youichi; Tatebe, Hiroaki; Kimoto, Masahide

    2017-12-01

    This study discusses how much of the biases in top-of-atmosphere (TOA) radiation and clouds can be removed by parameter tuning in the present-day simulation of a climate model in the Coupled Model Inter-comparison Project phase 5 (CMIP5) generation. We used output of a perturbed parameter ensemble (PPE) experiment conducted with an atmosphere-ocean general circulation model (AOGCM) without flux adjustment. The Model for Interdisciplinary Research on Climate version 5 (MIROC5) was used for the PPE experiment. Output of the PPE was compared with satellite observation data to evaluate the model biases and the parametric uncertainty of the biases with respect to TOA radiation and clouds. The results indicate that removing or changing the sign of the biases by parameter tuning alone is difficult. In particular, the cooling bias of the shortwave cloud radiative effect at low latitudes could not be removed, neither in the zonal mean nor at each latitude-longitude grid point. The bias was related to the overestimation of both cloud amount and cloud optical thickness, which could not be removed by the parameter tuning either. However, they could be alleviated by tuning parameters such as the maximum cumulus updraft velocity at the cloud base. On the other hand, the bias of the shortwave cloud radiative effect in the Arctic was sensitive to parameter tuning. It could be removed by tuning such parameters as albedo of ice and snow both in the zonal mean and at each grid point. The obtained results illustrate the benefit of PPE experiments which provide useful information regarding effectiveness and limitations of parameter tuning. Implementing a shallow convection parameterization is suggested as a potential measure to alleviate the biases in radiation and clouds.

  1. Effectiveness and limitations of parameter tuning in reducing biases of top-of-atmosphere radiation and clouds in MIROC version 5

    Directory of Open Access Journals (Sweden)

    T. Ogura

    2017-12-01

    Full Text Available This study discusses how much of the biases in top-of-atmosphere (TOA radiation and clouds can be removed by parameter tuning in the present-day simulation of a climate model in the Coupled Model Inter-comparison Project phase 5 (CMIP5 generation. We used output of a perturbed parameter ensemble (PPE experiment conducted with an atmosphere–ocean general circulation model (AOGCM without flux adjustment. The Model for Interdisciplinary Research on Climate version 5 (MIROC5 was used for the PPE experiment. Output of the PPE was compared with satellite observation data to evaluate the model biases and the parametric uncertainty of the biases with respect to TOA radiation and clouds. The results indicate that removing or changing the sign of the biases by parameter tuning alone is difficult. In particular, the cooling bias of the shortwave cloud radiative effect at low latitudes could not be removed, neither in the zonal mean nor at each latitude–longitude grid point. The bias was related to the overestimation of both cloud amount and cloud optical thickness, which could not be removed by the parameter tuning either. However, they could be alleviated by tuning parameters such as the maximum cumulus updraft velocity at the cloud base. On the other hand, the bias of the shortwave cloud radiative effect in the Arctic was sensitive to parameter tuning. It could be removed by tuning such parameters as albedo of ice and snow both in the zonal mean and at each grid point. The obtained results illustrate the benefit of PPE experiments which provide useful information regarding effectiveness and limitations of parameter tuning. Implementing a shallow convection parameterization is suggested as a potential measure to alleviate the biases in radiation and clouds.

  2. Famous puzzles of great mathematicians

    CERN Document Server

    Petković, Miodrag S

    2009-01-01

    This entertaining book presents a collection of 180 famous mathematical puzzles and intriguing elementary problems that great mathematicians have posed, discussed, and/or solved. The selected problems do not require advanced mathematics, making this book accessible to a variety of readers. Mathematical recreations offer a rich playground for both amateur and professional mathematicians. Believing that creative stimuli and aesthetic considerations are closely related, great mathematicians from ancient times to the present have always taken an interest in puzzles and diversions. The goal of this

  3. Navvus FFR to reduce CONTRAst, Cost and radiaTion (CONTRACT); insights from a single-centre clinical and economical evaluation with the RXi Rapid-Exchange FFR device.

    Science.gov (United States)

    Masdjedi, Kaneshka; Van Mieghem, Nicolas M; Diletti, Roberto; van Geuns, Robert-Jan; de Jaegere, Peter; Regar, Evelyn; Zijlstra, Felix; van Domburg, Ron T; Daemen, Joost

    2017-04-15

    To assess whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. FFR is the mainstay of functional hemodynamic assessment of coronary artery lesions. The RXi Navvus system (ACIST Medical Systems, Eden Prairie, MN) is a monorail microcatheter with FFR-measurement capability through optical pressure sensor technology. This is an investigator-initiated, prospective, single-center, observational cohort study. A total of 238 patients were enrolled, 97 patients with Navvus and 141 with conventional pressure-wire based FFR (PW-FFR). Final analyses were performed on the cohort in which only 1 device was used (82 Navvus procedures vs. 136 PW-FFR procedures). No significant differences were found in the total amount of contrast used (150±77 vs 147±79ml; p=0.81), radiation use (6200±4601 vs. 5076±4655 centiG∗cm 2 ; p=0.09) or costs (€1994,- vs. €1930,-; p=0.32) in the Navvus vs. PW-FFR groups respectively. No significant differences were found in the amount of contrast used, total procedural costs or radiation when the Navvus system was used as compared to conventional FFR wires. CONTRACT is an investigator-initiated, prospective, single-center, observational cohort study that evaluated whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. Use of the RXi Navvus system was associated with comparable procedural costs, amount of radiation and contrast used as compared to PW-FFR systems. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  4. Making a Great First Impression

    Science.gov (United States)

    Evenson, Renee

    2007-01-01

    Managers and business owners often base hiring decisions on first impressions. That is why it is so important to teach students to make a great first impression--before they go on that first job interview. Managers do not have unrealistic expectations, they just want to hire people who they believe can develop into valuable employees. A nice…

  5. Great Basin paleoenvironmental studies project

    International Nuclear Information System (INIS)

    1993-01-01

    Project goals, project tasks, progress on tasks, and problems encountered are described and discussed for each of the studies that make up the Great Basin Paleoenvironmental Studies Project for Yucca Mountain. These studies are: Paleobotany, Paleofauna, Geomorphology, and Transportation. Budget summaries are also given for each of the studies and for the overall project

  6. The Great Books and Economics.

    Science.gov (United States)

    Hartley, James E.

    2001-01-01

    Describes an introductory economics course in which all of the reading material is drawn from the Great Books of Western Civilization. Explains the rationale and mechanics of the course. Includes an annotated course syllabus that details how the reading material relates to the lecture material. (RLH)

  7. Great tit hatchling sex ratios

    NARCIS (Netherlands)

    Lessells, C.M.; Mateman, A.C.; Visser, J.

    1996-01-01

    The sex of Great Tit Parus major nestlings was determined using PCR RAPDs. Because this technique requires minute amounts of DNA, chicks could be sampled soon (0-2d) after hatching, before any nestling mortality occurred. The proportion of males among 752 chicks hatching in 102 broods (98.9% of

  8. The Great Gatsby. [Lesson Plan].

    Science.gov (United States)

    Zelasko, Ken

    Based on F. Scott Fitzgerald's novel "The Great Gatsby," this lesson plan presents activities designed to help students understand that adapting part of a novel into a dramatic reading makes students more intimate with the author's intentions and craft; and that a part of a novel may lend itself to various oral interpretations. The main activity…

  9. Great Basin wildlife disease concerns

    Science.gov (United States)

    Russ Mason

    2008-01-01

    In the Great Basin, wildlife diseases have always represented a significant challenge to wildlife managers, agricultural production, and human health and safety. One of the first priorities of the U.S. Department of Agriculture, Division of Fish and Wildlife Services was Congressionally directed action to eradicate vectors for zoonotic disease, particularly rabies, in...

  10. Topical application of β-radiation to reduce intimal hyperplasia after carotid artery balloon injury in rabbit A possible application for brachytherapy in vascular surgery

    International Nuclear Information System (INIS)

    Rosenthal, David; Stevens, Scott L.; Skillern, C.S.; Wellons, Eric D.; Robinson, Keith; Matsuura, John H.; Gannon, Brian J.

    2002-01-01

    Purpose: Endovascular brachytherapy for the prevention of intimal hyperplasia (IH) and restenosis after balloon/stent angioplasty has proven effective both in animal preparations and clinical trials. A variety of β-emitting isotopes and catheter-based devices have been developed for the delivery of low-dose radiation in clinical coronary and peripheral trials. No platform, however, has yet been developed for brachytherapy in concert with vascular surgical operations. The purpose of this study was to evaluate the vascular histopathologic response following balloon injury to rabbit carotid arteries with and without topically applied low-dose β-radiation. Methods: The β-emitting isotope strontium-90 (Sr-90) was conjugated onto the matrix of polypropylene (PLYP) mesh. Rabbit carotid arteries were balloon-injured with a no. 2 embolectomy catheter. Six carotid arteries were wrapped with nonradioactive PLYP mesh (controls) and Sr-90 (∼90 μCi) PLYP mesh in order to deliver low-dose radiation to the vessel wall from the external (adventitial) surface. Tissue was harvested at 6 weeks and processed for histologic examination. Results: There was consistent blockade of fibrocellular neointima formation with virtually no neointima present in all treated segments, compared to moderate neointima formation in controls. Medial thinning and smooth muscle cell (SMC) necrosis were also associated with topical brachytherapy. Conclusion: β-Radiation applied by an externally wrapped PLYP mesh labeled with Sr-90 markedly suppressed neointima formation in an animal vascular surgical injury model. Further studies, however, are necessary to determine a suitable isotope and dosage for clinical application

  11. Ionizing radiation from 60Co and electron accelerator in reducing the population of Salmonella sp. inoculated in chicken meatballs: evaluation of acceptance by consumer

    International Nuclear Information System (INIS)

    Saito, Juliana

    2003-01-01

    Salmonella sp. is one of the main microorganisms that causes outbreaks of food borne diseases associated to poultry, and among its derivatives, the chicken meatballs are getting the favorites of the consumer. In the attempt to improve microbiological food safety, a method that has been hardly studied is the irradiation. To study the viability of the use o ionizing radiation originated from 60 Co and electrons accelerator in the reduction of Salmonella sp., frozen chickens meatballs were inoculated with 10 4 CFU/g of Salmonella sp., with needle and syringe. Subsequently they were exposure to doses of 1.5, 2.0, 2.5 and 3.0 kGy and Salmonella sp. was enumerated. Chicken meatballs were exposed to doses 3.0, 4.0 and 5.0 kGy and submitted to sensory analysis. The gamma radiation from 60 CO was effective in the reduction of Salmonella sp. inoculated in chicken meatballs. The ionizing radiation originated from electron beam was not effective in the conditions applied in this research. The commercial chicken meatballs prepared with chicken meat, mixed up with soy protein, seasoning and anti-oxidants additives did not loose their sensorial quality when exposure to doses of 3.0, 4.0 and 5.0 kGy and, in a general way, the consumers showed to be disposed to buy the irradiation product (author)

  12. A miR-21 inhibitor enhances apoptosis and reduces G2-M accumulation induced by ionizing radiation in human glioblastoma U251 cells

    International Nuclear Information System (INIS)

    Li, Yi; Li, Qiang; Asai, Akio; Kawamoto, Keiji; Zhao Shiguang; Zhen Yunbo; Teng Lei

    2011-01-01

    MicroRNAs (miRNAs) are small noncoding RNAs that take part in diverse biological processes by suppressing target gene expression. Elevated expression of miR-21 has been reported in many types of human cancers. Radiotherapy is a standard adjuvant treatment for patients with glioblastoma. However, the resistance of glioblastoma cells to radiation limits the success of this treatment. In this study, we found that miR-21 expression was upregulated in response to ionizing radiation (IR) in U251 cells, which suggested that miR-21 could be involved in the response of U251 cells to radiation. We showed that a miR-21 inhibitor enhanced IR-induced glioblastoma cell growth arrest and increased the level of apoptosis, which was probably caused by abrogation of the G 2 -M arrest induced by IR. Further research demonstrated that the miR-21 inhibitor induced the upregulation of Cdc25A. Taken together, these findings suggest that miR-21 inhibitor can increase IR-induced growth arrest and apoptosis in U251 glioblastoma cells, at least in part by abrogating G 2 -M arrest, and that Cdc25A is a potential target of miR-21. (author)

  13. REC-2006-A Fractionated Extract of Podophyllum hexandrum Protects Cellular DNA from Radiation-Induced Damage by Reducing the Initial Damage and Enhancing Its Repair In Vivo.

    Science.gov (United States)

    Chaudhary, Pankaj; Shukla, Sandeep Kumar; Sharma, Rakesh Kumar

    2011-01-01

    Podophyllum hexandrum, a perennial herb commonly known as the Himalayan May Apple, is well known in Indian and Chinese traditional systems of medicine. P. hexandrum has been widely used for the treatment of venereal warts, skin infections, bacterial and viral infections, and different cancers of the brain, lung and bladder. This study aimed at elucidating the effect of REC-2006, a bioactive fractionated extract from the rhizome of P. hexandrum, on the kinetics of induction and repair of radiation-induced DNA damage in murine thymocytes in vivo. We evaluated its effect on non-specific radiation-induced DNA damage by the alkaline halo assay in terms of relative nuclear spreading factor (RNSF) and gene-specific radiation-induced DNA damage via semi-quantitative polymerase chain reaction. Whole body exposure of animals with gamma rays (10 Gy) caused a significant amount of DNA damage in thymocytes (RNSF values 17.7 ± 0.47, 12.96 ± 1.64 and 3.3 ± 0.014) and a reduction in the amplification of β-globin gene to 0, 28 and 43% at 0, 15 and 60 min, respectively. Administrating REC-2006 at a radioprotective concentration (15 mg kg(-1) body weight) 1 h before irradiation resulted in time-dependent reduction of DNA damage evident as a decrease in RNSF values 6.156 ± 0.576, 1.647 ± 0.534 and 0.496 ± 0.012, and an increase in β-globin gene amplification 36, 95 and 99%, at 0, 15 and 60 min, respectively. REC-2006 scavenged radiation-induced hydroxyl radicals in a dose-dependent manner stabilized DPPH free radicals and also inhibited superoxide anions. Various polyphenols and flavonoides present in REC-2006 might contribute to scavenging of radiation-induced free radicals, thereby preventing DNA damage and stimulating its repair.

  14. Natural and artificial radioactivity in Great Bratislava

    International Nuclear Information System (INIS)

    Lanc, J.

    1997-01-01

    The results of the aviation measurement of the gamma-radiation are presented in the form of the maps of iso-lines of the concentration of the natural radioactive elements (potassium, uranium, thorium) and artificial radionuclides (cesium-137, cesium-134). From the obtained dates the maps of dose rate of the gamma-radiation in the air are calculated, of the dose equivalent rate and the map of the fraction of the dose equivalent rate from the natural elements potassium, uranium, thorium. The natural radioactivity of the minerals in the Great Bratislava region, especially for the extreme low values of the contain of the thorium, does not amount the average values of the radioactivity of the Earth crust. The area activity of cesium-137 are in the range 2 - 10 kBq.m -2 and cesium-134 is 1 - 2.5 kBq.m -2 . From the point of view of the summary level of the external irradiation from the Earth surface the measured zone as relative even is evaluated, in the range 10-100 nSv.h -1 . The total average level of the dose rate of the external irradiation of man (inclusively from the cosmic radiation 40-50 nSv.h -1 ) in the conditions of Bratislava is 100 nSv.h -1 . The contribution of external component of the irradiation is 40-100 nSv.h -1 (0.1-0.3 mSv.y -1 ). The dose equivalent commitment of internal component from the cesium-137 is for the all age category of the population under the level negligible risk 0.01 mSv.y -1 [sk

  15. Disinfecting wounds with radiation

    International Nuclear Information System (INIS)

    Cuttler, J.M.

    2002-01-01

    Infection with clostridium bacteria, which live in the soil, is most often associated with war wounds, car accidents, complicated abortions, etc. The incidence is highest in areas with poor access to proper wound care. Such infections lead to gas gangrene, a deadly disease that spreads very quickly in the body and causes rapid death. Present-day treatment consists of administering antibiotics and surgical removal of dead, damaged and infected tissue. Amputation is usually necessary to control the spread of the infection, which can advance at the rate of six inches per hour. Before the 1940s, this disease was treated successfully with low doses (50 rad) of radiation (X-rays) in the area of infection. A review of 364 cases treated in this manner, from 1928 until 1940, indicated that patient mortality would be reduced from 50 percent (or higher) to ∼5 percent if patients were treated reasonably early and with the correct technique. X-ray therapy stopped the infection without the need for amputation to control its spread. Low-dose irradiation (LDI) therapy, given immediately, acted as a prophylaxis to prevent the onset of gas gangrene. This is but one example of the extensive use of radiation treatment of many types of infections, before the advent of antibiotics. Low doses are inadequate to kill invading bacteria directly, however, they will stimulate our defences to destroy the infection. The observed beneficial effects are consistent with the large amount of scientific evidence of radiation hormesis - the stimulation of an organism's own defences by low doses of radiation (to destroy invaders and heal wounds). In view of the ineffectiveness of antibiotics in many cases and the evolution of antibiotic-resistant strains of bacteria, physicians should start to use LDI therapies again. Many patients would benefit greatly. (author)

  16. Study on reducing radiation dose in dental radiography for children, 1. The seltering effects of lead content rubber sheet and ready-made apron

    Energy Technology Data Exchange (ETDEWEB)

    Shikone, Mitsuru; Tsuchida, Atsushi; Tateno, Hidemi; Uchimura, Noboru; Higaki, Morio; Kanno, Masanori; Higashi, Tomomitsu

    1986-12-01

    X-ray examination is one of the effective diagnoses in dentistry. And it is difficult to conduct a precise dental examination without X-ray films, especially in pedodontics. However, radiography may be attended with many radiation injury, and we must perform the complete protection of patients when taking X-ray radiography for children, because their tissues are much more sensitive to radiation than those of adult. Children have some radiosensitive immature organs such as the thyroid gland, eyes (crystalline lens), gonad etc., accordingly, it is very important to protect them from exposure of X-rey. It has been suggested that the thyroid gland is the most sensitive to radiation among many organs. We, therefore, establish a protector for children's thyroid gland as soon as possible. In this study, the auther had designed X-ray protecting rubber sheet which had various lead contents, for finding an optimum condition of the protector. Additionally, the sheltering effects were compared among ready-made protectors. 1. It was satisfactory for complete sheltering of direct beam that the rubber sheet contained 0.375 mmPb, 0.5 mmPb, and 0.75 mmPb, at the tubevoltage of 65 kVp, 70 kVp and 80 kVp, respectively. 2. The radiolucency ratio of Hagoromo Apron containing 0.25 mmPb was 0 % at 65 kVp, and that of X-ray Shield containing 0.50 mmPb was 0 % at 65, 70 kVp and 80 kVp too. 3. Among the ready-made aprons, there was one which had less lead content than the indicated value.

  17. Sudden Exposure to Solar UV-B Radiation Reduces Net CO2 Uptake and Photosystem I Efficiency in Shade-Acclimated Tropical Tree Seedlings1

    Science.gov (United States)

    Krause, G. Heinrich; Grube, Esther; Virgo, Aurelio; Winter, Klaus

    2003-01-01

    Tree seedlings developing in the understory of the tropical forest have to endure short periods of high-light stress when tree-fall gaps are formed, and direct solar radiation, including substantial UV light, reaches the leaves. In experiments simulating the opening of a tree-fall gap, the response of photosynthesis in leaves of shade-acclimated seedlings (Anacardium excelsum, Virola surinamensis, and Calophyllum longifolium) to exposure to direct sunlight (for 20–50 min) was investigated in Panama (9°N). To assess the effects of solar UV-B radiation (280–320 nm), the sunlight was filtered through plastic films that selectively absorbed UV-B or transmitted the complete spectrum. The results document a strong inhibition of CO2 assimilation by sun exposure. Light-limited and light-saturated rates of photosynthetic CO2 uptake by the leaves were affected, which apparently occurred independently of a simultaneous inhibition of potential photosystem (PS) II efficiency. The ambient UV-B light substantially contributed to these effects. The photochemical capacity of PSI, measured as absorbance change at 810 nm in saturating far-red light, was not significantly affected by sun exposure of the seedlings. However, a decrease in the efficiency of P700 photooxidation by far-red light was observed, which was strongly promoted by solar UV-B radiation. The decrease in PSI efficiency may result from enhanced charge recombination in the reaction center, which might represent an incipient inactivation of PSI, but contributes to thermal dissipation of excessive light energy and thereby to photoprotection. PMID:12586898

  18. The EOS 2D/3D X-ray imaging system: A cost-effectiveness analysis quantifying the health benefits from reduced radiation exposure

    International Nuclear Information System (INIS)

    Faria, Rita; McKenna, Claire; Wade, Ros; Yang, Huiqin; Woolacott, Nerys; Sculpher, Mark

    2013-01-01

    Objectives: To evaluate the cost-effectiveness of the EOS ® 2D/3D X-ray imaging system compared with standard X-ray for the diagnosis and monitoring of orthopaedic conditions. Materials and methods: A decision analytic model was developed to quantify the long-term costs and health outcomes, expressed as quality-adjusted life years (QALYs) from the UK health service perspective. Input parameters were obtained from medical literature, previously developed cancer models and expert advice. Threshold analysis was used to quantify the additional health benefits required, over and above those associated with radiation-induced cancers, for EOS ® to be considered cost-effective. Results: Standard X-ray is associated with a maximum health loss of 0.001 QALYs, approximately 0.4 of a day in full health, while the loss with EOS ® is a maximum of 0.00015 QALYs, or 0.05 of a day in full health. On a per patient basis, EOS ® is more expensive than standard X-ray by between £10.66 and £224.74 depending on the assumptions employed. The results suggest that EOS ® is not cost-effective for any indication. Health benefits over and above those obtained from lower radiation would need to double for EOS to be considered cost-effective. Conclusion: No evidence currently exists on whether there are health benefits associated with imaging improvements from the use of EOS ® . The health benefits from radiation dose reductions are very small. Unless EOS ® can generate additional health benefits as a consequence of the nature and quality of the image, comparative patient throughput with X-ray will be the major determinant of cost-effectiveness

  19. The EOS 2D/3D X-ray imaging system: A cost-effectiveness analysis quantifying the health benefits from reduced radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Rita, E-mail: rita.nevesdefaria@york.ac.uk [Centre for Health Economics, University of York, York (United Kingdom); McKenna, Claire [Centre for Health Economics, University of York, York (United Kingdom); Wade, Ros; Yang, Huiqin; Woolacott, Nerys [Centre for Reviews and Dissemination, University of York, York (United Kingdom); Sculpher, Mark [Centre for Health Economics, University of York, York (United Kingdom)

    2013-08-15

    Objectives: To evaluate the cost-effectiveness of the EOS{sup ®} 2D/3D X-ray imaging system compared with standard X-ray for the diagnosis and monitoring of orthopaedic conditions. Materials and methods: A decision analytic model was developed to quantify the long-term costs and health outcomes, expressed as quality-adjusted life years (QALYs) from the UK health service perspective. Input parameters were obtained from medical literature, previously developed cancer models and expert advice. Threshold analysis was used to quantify the additional health benefits required, over and above those associated with radiation-induced cancers, for EOS{sup ®} to be considered cost-effective. Results: Standard X-ray is associated with a maximum health loss of 0.001 QALYs, approximately 0.4 of a day in full health, while the loss with EOS{sup ®} is a maximum of 0.00015 QALYs, or 0.05 of a day in full health. On a per patient basis, EOS{sup ®} is more expensive than standard X-ray by between £10.66 and £224.74 depending on the assumptions employed. The results suggest that EOS{sup ®} is not cost-effective for any indication. Health benefits over and above those obtained from lower radiation would need to double for EOS to be considered cost-effective. Conclusion: No evidence currently exists on whether there are health benefits associated with imaging improvements from the use of EOS{sup ®}. The health benefits from radiation dose reductions are very small. Unless EOS{sup ®} can generate additional health benefits as a consequence of the nature and quality of the image, comparative patient throughput with X-ray will be the major determinant of cost-effectiveness.

  20. Radiation safety of soil moisture neutron probes

    International Nuclear Information System (INIS)

    Oresegun, M.O.

    2000-01-01

    The neutron probe measures sub-surface moisture in soil and other materials by means of high energy neutrons and a slow (thermal) neutron detector. Exposure to radiation, including neutrons, especially at high doses, can cause detrimental health effects. In order to achieve operational radiation safety, there must be compliance with protection and safety standards. The design and manufacture of commercially available neutron moisture gauges are such that risks to the health of the user have been greatly reduced. The major concern is radiation escape from the soil during measurement, especially under dry conditions and when the radius of influence is large. With appropriate work practices as well as good design and manufacture of gauges, recorded occupational doses have been well below recommended annual limits. It can be concluded that the use of neutron gauges poses not only acceptable health and safety risks but, in fact, the risks are negligible. Neutron gauges should not be classified as posing high potential health hazards. (author)

  1. Nuclear power and low level radiation hazards

    International Nuclear Information System (INIS)

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

    1979-03-01

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

  2. Failure and Redemption of Multifilter Rotating Shadowband Radiometer (MFRSR/Normal Incidence Multifilter Radiometer (NIMFR Cloud Screening: Contrasting Algorithm Performance at Atmospheric Radiation Measurement (ARM North Slope of Alaska (NSA and Southern Great Plains (SGP Sites

    Directory of Open Access Journals (Sweden)

    James Barnard

    2013-09-01

    Full Text Available Well-known cloud-screening algorithms, which are designed to remove cloud-contaminated aerosol optical depths (AOD from Multifilter Rotating Shadowband Radiometer (MFRSR and Normal Incidence Multifilter Radiometer (NIMFR measurements, have exhibited excellent performance at many middle-to-low latitude sites around world. However, they may occasionally fail under challenging observational conditions, such as when the sun is low (near the horizon and when optically thin clouds with small spatial inhomogeneity occur. Such conditions have been observed quite frequently at the high-latitude Atmospheric Radiation Measurement (ARM North Slope of Alaska (NSA sites. A slightly modified cloud-screening version of the standard algorithm is proposed here with a focus on the ARM-supported MFRSR and NIMFR data. The modified version uses approximately the same techniques as the standard algorithm, but it additionally examines the magnitude of the slant-path line of sight transmittance and eliminates points when the observed magnitude is below a specified threshold. Substantial improvement of the multi-year (1999–2012 aerosol product (AOD and its Angstrom exponent is shown for the NSA sites when the modified version is applied. Moreover, this version reproduces the AOD product at the ARM Southern Great Plains (SGP site, which was originally generated by the standard cloud-screening algorithms. The proposed minor modification is easy to implement and its application to existing and future cloud-screening algorithms can be particularly beneficial for challenging observational conditions.

  3. After the great nuclear debate

    Energy Technology Data Exchange (ETDEWEB)

    Hill, J [UKAEA Headquarters, London

    1981-01-01

    Problems of public perception of nuclear power (environmental damage, risks of large disasters, the effect of low level radiation, nuclear waste management) are considered and their correspondence to the problems as seen from inside the industry examined. The problems of public presentation by the industry of what it is trying to do and of explaining why it believes that what it is doing is responsible and in the long term interests of the society are discussed.

  4. Improved image quality with simultaneously reduced radiation exposure: Knowledge-based iterative model reconstruction algorithms for coronary CT angiography in a clinical setting.

    Science.gov (United States)

    André, Florian; Fortner, Philipp; Vembar, Mani; Mueller, Dirk; Stiller, Wolfram; Buss, Sebastian J; Kauczor, Hans-Ulrich; Katus, Hugo A; Korosoglou, Grigorios

    The aim of this study was to assess the potential for radiation dose reduction using knowledge-based iterative model reconstruction (K-IMR) algorithms in combination with ultra-low dose body mass index (BMI)-adapted protocols in coronary CT angiography (coronary CTA). Forty patients undergoing clinically indicated coronary CTA were randomly assigned to two groups with BMI-adapted (I: quality was significantly better in the ULD group using K-IMR CR 1 compared to FBP, iD 2 and iD 5 in the LD group, resulting in fewer non-diagnostic coronary segments (2.4% vs. 11.6%, 9.2% and 6.1%; p quality compared to LD protocols with FBP or hybrid iterative algorithms. Therefore, K-IMR allows for coronary CTA examinations with high diagnostic value and very low radiation exposure in clinical routine. Copyright © 2017 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  5. Radiation treatment of foodstuffs

    International Nuclear Information System (INIS)

    Luther, T.; Huebner, G.

    1990-10-01

    In addition to fundamental demands on radiation and safety engineering of irradiation facilities, the necessity arises to optimize irradiation conditions by using facilities to capacity and thus reducing irradiation costs. The following subjects are dealt with in detail: rehabilitation of a pilot plant for radiation treatment of onions; examination of radiation resistance of components and equipment parts of food irradiation facilities; chemical dosimetry; relative measurement of the intensity of radioactive sources; thermo- and chemiluminescence to prove irradiation of foodstuffs; radiation induced sprout inhibition of potatoes; laboratory tests of delayed maturation of tomatoes; radiation treatment of strawberries; radiation treatment of forage; radiation induced sprout inhibition of acid-treated onions; radiation treatment of starch and potatoe products; radiation treatment of cosmetics; the universal radiation source UNI 88/26 for gamma irradiation facilities; microbiological aspects of food irradiation, and introduction of chicken irradiation on an industrial scale. (BBR) [de

  6. Evaluation of general-purpose collimators against high-resolution collimators with resolution recovery with a view to reducing radiation dose in myocardial perfusion SPECT: A preliminary phantom study.

    Science.gov (United States)

    Armstrong, Ian S; Saint, Kimberley J; Tonge, Christine M; Arumugam, Parthiban

    2017-04-01

    There is a growing focus on reducing radiation dose to patients undergoing myocardial perfusion imaging. This preliminary phantom study aims to evaluate the use of general-purpose collimators with resolution recovery (RR) to allow a reduction in patient radiation dose. Images of a cardiac torso phantom with inferior and anterior wall defects were acquired on a GE Infinia and Siemens Symbia T6 using both high-resolution and general-purpose collimators. Imaging time, a surrogate for administered activity, was reduced between 35% and 40% with general-purpose collimators to match the counts acquired with high-resolution collimators. Images were reconstructed with RR with and without attenuation correction. Two pixel sizes were also investigated. Defect contrast was measured. Defect contrast on general-purpose images was superior or comparable to the high-resolution collimators on both systems despite the reduced imaging time. Infinia general-purpose images required a smaller pixel size to be used to maintain defect contrast, while Symbia T6 general-purpose images did not require a change in pixel size to that used for standard myocardial perfusion SPECT. This study suggests that general-purpose collimators with RR offer a potential for substantial dose reductions while providing similar or better image quality to images acquired using high-resolution collimators.

  7. Improved radiation protection for physicians performing cardiac catheterization

    International Nuclear Information System (INIS)

    Gertz, E.W.; Wisneski, J.A.; Gould, R.G.; Akin, J.R.

    1982-01-01

    Physicians and their assistants performing diagnostic angiography must be concerned with the radiation exposure they receive. The introduction of hemiaxial projections for imaging has increased diagnostic accuracy but has also greatly increased the physicians' exposure to scattered radiation. This increase is especially critical for the eyes and thyroid of the physician who routinely performs these procedures. To reduce such exposure a ceiling-suspended shield (60 x 45 cm), made of 6.4 mm glass with a 19.5 kg/m2 (4 lb/ft2) lead equivalency, was developed. During procedures the shield is interposed between the physician and the region of the patient acting as the source of scattered radiation. The degree of radiation protection to the operator was assessed by measuring the distribution of scattered radiation in the vicinity of the operator with and without the shield. The effectiveness of the shield was determined in the 30 degrees right anterior oblique (RAO), 5 degrees left anterior oblique (LAO), 35 degrees LAO, and 50 degrees LAO-15 degrees cranial angulations. At critical heights such as the level of the eyes and thyroid, scattered radiation levels were reduced by 85% or greater in all angulations. Without interfering with the physician's ability to observe the patient or manipulate the catheter, this shield can significantly reduce the physician's exposure to radiation

  8. The application of entropy weight TOPSIS method to optimal points in monitoring the Xinjiang radiation environment

    International Nuclear Information System (INIS)

    Feng Guangwen; Hu Youhua; Liu Qian

    2009-01-01

    In this paper, the application of the entropy weight TOPSIS method to optimal layout points in monitoring the Xinjiang radiation environment has been indroduced. With the help of SAS software, It has been found that the method is more ideal and feasible. The method can provide a reference for us to monitor radiation environment in the same regions further. As the method could bring great convenience and greatly reduce the inspecting work, it is very simple, flexible and effective for a comprehensive evaluation. (authors)

  9. Radiation myelopathy

    Energy Technology Data Exchange (ETDEWEB)

    Howell, D A [Derbyshire Royal Infirmary, Derby (UK)

    1979-10-01

    Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed.

  10. Radiation myelopathy

    International Nuclear Information System (INIS)

    Howell, D.A.

    1979-01-01

    Following high-dose radiotherapy treatment of tumours, there is a risk of destructive radiation myelopathy developing a few months later as a result of spinal cord irradiation. The emphasis of the present article is on the mechanism of the development of radiation myelopathy. It is suggested that, in the irradiated segments, the normal endothelial cells lining the penetrating arteries and capillaries are replaced by abnormal cells during the latent period. Radiation-induced mutations or chromosomal aberrations are contained in these cells, thus provoking an immunological response. During the attempted rejection of these cells, protein-rich plasma filtrate is leaked into the artery walls and nervous tissue, causing the destructive myelopathy. The signs of paralysis of spinal cord function may be caused either by infarcts or by oedema of the white matter. Since both diagnosis and treatment are difficult, it is necessary to concentrate on prevention by, whenever possible, reducing radiation doses to below tolerance limits during radiotherapy. As regards radiotherapy in children, it is currently believed that there is little or no difference in radiation tolerance between the child and the adult nervous system. Some early benign forms of radiation myelopathy are also briefly discussed. (UK)

  11. The work of Jules Horowitz. The great Cea actors

    International Nuclear Information System (INIS)

    Arnaudet, L.; Deloche, R.; Procope, L.

    1999-01-01

    Jules Horowitz contributed to the heart calculation of the first french reactor Zoe. He developed the first experimental reactors, invested himself in the reactors physics and helped with EDF to the realisation of the French electronuclear programme. His work is marked out the building of great research devices: The Laue-Langevin Institute (ILL), The European Source of Synchrotron radiation (ESRF), the great national heavy ions accelerator (GANIL) the superconductor tokamak TORE SUPRA) the Leon Brillouin Laboratory (LLB), the Frederic Joliot hospital service (SHFJ). (N.C.)

  12. Mortality of tyrophagus putrescentiae (Schrank) females exposed to a high ratio of gamma-irradiated males as an index of radiation impact on sexual vigor of males

    International Nuclear Information System (INIS)

    Ignatowicz, S.

    1990-01-01

    A 40 or 60 krad dose of gamma radiation reduce slightly sexual activity of the males but male activity is greatly reduced as the radiation dose increases from 60 to 120 krad. Females of the mold mite, Tyrophagus, putrescentiae (Schrank), molested by males present at a 3:1 or 5:1 ratio live shorter than females kept with one male. The SAG test can be applied to compare sexual activity of males treated with different dosage of gamma irradiation

  13. Radiation in buildings

    International Nuclear Information System (INIS)

    1981-01-01

    The report presents facts about radiation, its origin and risks. It is stated that the natural radiation is dependent on the bedrock. Various control methods and ways to reduce high radiation levels are described. The information is based upon present-day knowledge of the inconvenience about radon. (G.B.)

  14. Overexpression of extracellular superoxide dismutase reduces severity of radiation-induced lung toxicity through downregulation of the TGF-β signal transduction pathway

    International Nuclear Information System (INIS)

    Rabbani, Z.N.; Anscher, M.S.; Archer, E.; Chen, L.; Samulski, T.V.; Folz, R.J.; Dewhirst, M.W.; Vujaskovic, Z.

    2003-01-01

    The objective of this study is to determine whether overexpression of ECSOD, ameliorates acute radiation induced lung injury by inhibiting activation of TGF-β and down regulating phosphorylation of (p)Smad 3 signal transduction protein. Transgenic (TG) B6C3 mice that overexpress human EC-SOD (hEC-SOD) and wild-type (WT) littermates received single dose of 15 Gy to the whole thorax and sacrificed at 1day, 1wk, 2wk, 3wk, 6wk, 10 and 14 weeks. Different endpoints were assessed to look for lung damage. Starting at 3rd week after radiation, there was significant increase in breathing rates, right lung wet weights and lung tissue damage score of XRT-WT vs. XRT-TG (p<0.05). In BALF, total cell counts per ml were significantly increased in XRT-WT whereas XRT-TG animals did not show any significant increase except at 14 weeks after irradiation (p<0.05). Macrophages and lymphocytes were the predominant inflammatory cells in BALF of XRT-WT compared to XRT-TG (p<0.05). XRT-WT group had a significantly higher percentage of activated TGF-β1 than the XRT-TG (p=0.04) at 14 weeks. There was a mild immunoreactivity of pSmad3 in bronchial epithelium and type II pneumocytes of control animals. In XRT-WT pSmad3 immunostaining was moderate at 1 week and moderate to strong at 3, 6 and 10 weeks whereas in XRT-TG mice immmunostaining was mild to moderate. This study shows that, the overexpression of ECSOD in transgenic animals is radioprotective in acute phase of radiation induced lung injury. Fewer inflammatory cells in XRT-TG group confirms the deprivation of important source for free radicals and TGF-β cytokine. Significant reduction in TGF-β activation in ECSOD overexpressing animals, followed by downregulation of pSmad3 indicates important role of reactive oxygen species in activation of TGF-β signal transduction pathway

  15. Learning and the Great Moderation

    OpenAIRE

    Bullard, James B.; Singh, Aarti

    2009-01-01

    We study a stylized theory of the volatility reduction in the U.S. after 1984 - the Great Moderation - which attributes part of the stabilization to less volatile shocks and another part to more difficult inference on the part of Bayesian households attempting to learn the latent state of the economy. We use a standard equilibrium business cycle model with technology following an unobserved regime-switching process. After 1984, according to Kim and Nelson (1999a), the variance of U.S. macroec...

  16. Pricing regulations in Great Britain

    International Nuclear Information System (INIS)

    Cicoletti, G.

    1993-01-01

    This paper briefly describes the structure and functions of Great Britain's essential electric power regulatory authority institutionalized by the 1989 British Electricity Act, i.e., the Office of Electricity Regulation, OFFER, and the responsibilities and tasks of the head of OFFER -the Director General of Electricity Supply (DGES). In particular, with regard to the latter, the paper describes how the DGES works together with regional electricity commissions to ensure the respect, by the various utilities, of consumer price caps and compliance with overall quality of service standards, as well as, to oversee 'pooling' activities by producers and distributors

  17. Pricing regulations in Great Britain

    International Nuclear Information System (INIS)

    Cicoletti, G.

    1993-01-01

    This paper briefly describes the structure and functions of Great Britain's essential electric power regulatory authority institutionalized by the 1989 British Electricity Act, i.e., the Office of Electricity Regulation, OFFER, and the responsibilities and tasks of the head of OFFER - the Director General of Electricity Supply (DGES). In particular, with regard to the latter, the paper describes how the DGES works together with regional electricity commissions to ensure the respect, by the various utilities, of consumer price caps and compliance with overall quality of service standards, as well as, to oversee 'pooling' activities by producers and distributors

  18. What killed Alexander the Great?

    Science.gov (United States)

    Battersby, Cameron

    2007-01-01

    The cause of the death of the Macedonian King, Alexander the Great, at Babylon in 323 BC has excited interest and conjecture throughout the ages. The information available in the surviving ancient sources, none of which is contemporaneous, has been reviewed and compared with modern knowledge as set out in several well-known recent surgical texts. The ancient sources record epic drinking by the Macedonian nobility since at least the time of Phillip II, Alexander's father. Alexander's sudden illness and death is likely to have resulted from a surgical complication of acute alcoholic excess.

  19. Commanders of the Great Victory

    Directory of Open Access Journals (Sweden)

    Anatoly Dmitriyevich Borshchov

    2015-01-01

    Full Text Available The honorary title of «commander» as well as the «admiral» is granted to a military or naval figure on the basis of public recognition of his personal contribution to the success of actions. Generals are usually individuals with creative thinking, the ability to foresee the development of military events. Generals usually have such personality traits as a strong will and determination, rich combat experience, credibility and high organizational skills. In an article dedicated to the 70th anniversary of the Soviet victory in the Great War examines the experience of formation and practice of the most talent-ed Soviet military leaders.

  20. Radiation chemistry

    International Nuclear Information System (INIS)

    Rodgers, F.; Rodgers, M.A.

    1987-01-01

    The contents of this book include: Interaction of ionizing radiation with matter; Primary products in radiation chemistry; Theoretical aspects of radiation chemistry; Theories of the solvated electron; The radiation chemistry of gases; Radiation chemistry of colloidal aggregates; Radiation chemistry of the alkali halides; Radiation chemistry of polymers; Radiation chemistry of biopolymers; Radiation processing and sterilization; and Compound index

  1. Can use of adaptive statistical iterative reconstruction reduce radiation dose in unenhanced head CT? An analysis of qualitative and quantitative image quality

    International Nuclear Information System (INIS)

    Østerås, Bjørn Helge; Heggen, Kristin Livelten; Pedersen, Hans Kristian; Andersen, Hilde Kjernlie; Martinsen, Anne Catrine T

    2016-01-01

    Iterative reconstruction can reduce image noise and thereby facilitate dose reduction. To evaluate qualitative and quantitative image quality for full dose and dose reduced head computed tomography (CT) protocols reconstructed using filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR). Fourteen patients undergoing follow-up head CT were included. All patients underwent full dose (FD) exam and subsequent 15% dose reduced (DR) exam, reconstructed using FBP and 30% ASIR. Qualitative image quality was assessed using visual grading characteristics. Quantitative image quality was assessed using ROI measurements in cerebrospinal fluid (CSF), white matter, peripheral and central gray matter. Additionally, quantitative image quality was measured in Catphan and vendor’s water phantom. There was no significant difference in qualitative image quality between FD FBP and DR ASIR. Comparing same scan FBP versus ASIR, a noise reduction of 28.6% in CSF and between −3.7 and 3.5% in brain parenchyma was observed. Comparing FD FBP versus DR ASIR, a noise reduction of 25.7% in CSF, and −7.5 and 6.3% in brain parenchyma was observed. Image contrast increased in ASIR reconstructions. Contrast-to-noise ratio was improved in DR ASIR compared to FD FBP. In phantoms, noise reduction was in the range of 3 to 28% with image content. There was no significant difference in qualitative image quality between full dose FBP and dose reduced ASIR. CNR improved in DR ASIR compared to FD FBP mostly due to increased contrast, not reduced noise. Therefore, we recommend using caution if reducing dose and applying ASIR to maintain image quality

  2. The Effect of Solvent, Hydrogen Peroxide and Dioxide Titanium on Degradation of PCBs, Using Microwave Radiation in Order to Reduce Occupational Exposure

    Directory of Open Access Journals (Sweden)

    Tajik Reza

    2014-07-01

    Full Text Available Polychlorinated biphenyls (PCBs are one group of persistent organic pollutants (POPs that are of international concern because of global distribution, persistence, and toxicity. Removal of these compounds from the environment remains a very difficult challenge because the compounds are highly hydrophobic and have very low solubility in water. A 900 W domestic microwave oven, pyrex vessel reactor, pyrex tube connector and condensing system were used in this experiment. Radiation was discontinuous and ray powers were 540, 720 and 900 W. The PCBS were analyzed by GC-ECD. The application of microwave radiation and H2O2/TiO2 agents for the degradation of polychlorinated biphenyl contaminated oil was explored in this study. PCB – contaminated oil was treated in a pyrex reactor by microwave irradiation at 2450 MHz with the addition of H2O2/TiO2. A novel grain TiO2 (GT01 was used. The determination of PCB residues in oil by gas chromatography (GC revealed that rates of PCB decomposition were highly dependent on microwave power, exposure time, ratio to solvent with transformer oil in 3:1, the optimal amount of GT01 (0.2 g and 0.116 mol of H2O2 were used in the study. It was suggested that microwave irradiation with the assistance of H2O2/TiO2 might be a potential technology for the degradation of PCB – contaminated oil. The experiments show that MW irradiation, H2O2 oxidant and TiO2 catalyst lead to a degradation efficiency of PCBs only in the presence of ethanol. The results showed that the addition of ethanol significantly enhanced degradation efficiency of PCBs.

  3. Great apes prefer cooked food.

    Science.gov (United States)

    Wobber, Victoria; Hare, Brian; Wrangham, Richard

    2008-08-01

    The cooking hypothesis proposes that a diet of cooked food was responsible for diverse morphological and behavioral changes in human evolution. However, it does not predict whether a preference for cooked food evolved before or after the control of fire. This question is important because the greater the preference shown by a raw-food-eating hominid for the properties present in cooked food, the more easily cooking should have been adopted following the control of fire. Here we use great