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1

ARM - Field Campaign - Carbonaceous Aerosol and Radiative Effects Study  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) Campaign Links CARES Website Related Campaigns Carbonaceous Aerosol and Radiation Effects Study (CARES) - Surface Meteorological Sounding 2010.05.26, Zaveri, OSC Carbonaceous Aerosol and Radiation Effects Study (CARES) Photo-Acoustic Aerosol Light Absorption and Scattering 2010.05.26, Arnott, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES): SMPS & CCN counter deployment during CARES/Cal-NEx 2010.05.04, Wang, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES) Ground Based Instruments 2010.04.01, Cziczo, OSC Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Carbonaceous Aerosol and Radiative Effects Study (CARES)

2

CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan  

SciTech Connect

Carbonaceous aerosol components, which include black carbon (BC), urban primary organic aerosols (POA), biomass burning aerosols, and secondary organic aerosols (SOA) from both urban and biogenic precursors, have been previously shown to play a major role in the direct and indirect radiative forcing of climate. The primary objective of the CARES 2010 intensive field study is to investigate the evolution of carbonaceous aerosols of different types and their effects on optical and cloud formation properties.

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-05-27T23:59:59.000Z

3

Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies  

E-Print Network (OSTI)

This dissertation aims to study the broadband optical properties and radiative effects of dust aerosols and ice clouds. It covers three main topics: the uncertainty of dust optical properties and radiative effects from the dust particle shape...

Yi, Bingqi

2013-07-09T23:59:59.000Z

4

Effect of microwave radiation on Jayadhar cotton fibers: WAXS studies  

SciTech Connect

Thermal effect in the form of micro wave energy on Jayadhar cotton fiber has been investigated. Microstructural parameters have been estimated using wide angle x-ray scattering (WAXS) data and line profile analysis program developed by us. Physical properties like tensile strength are correlated with X-ray results. We observe that the microwave radiation do affect significantly many parameters and we have suggested a multivariate analysis of these parameters to arrive at a significant result.

Niranjana, A. R., E-mail: arnphysics@gmail.com; Mahesh, S. S., E-mail: arnphysics@gmail.com; Divakara, S., E-mail: arnphysics@gmail.com; Somashekar, R., E-mail: arnphysics@gmail.com [Department of Studies in Physics, University of Mysore, Mysore-570006 (India)

2014-04-24T23:59:59.000Z

5

Study of effects of radiation on silicone prostheses. [/sup 60/Co  

SciTech Connect

Radiation effects on silicone gel and dose distribution of radiation through mammary prostheses were studied. Silicone gel behaves like tissue. Half value thickness for silicone gel and water are almost the same. Linear absorption coefficient for silicone gel and water are comparable.

Shedbalkar, A.R.; Devata, A.; Padanilam, T.

1980-06-01T23:59:59.000Z

6

CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan  

SciTech Connect

The CARES field campaign is motivated by the scientific issues described in the CARES Science Plan. The primary objectives of this field campaign are to investigate the evolution and aging of carbonaceous aerosols and their climate-affecting properties in the urban plume of Sacramento, California, a mid-size, mid-latitude city that is located upwind of a biogenic volatile organic compound (VOC) emission region. Our basic observational strategy is to make comprehensive gas, aerosol, and meteorological measurements upwind, within, and downwind of the urban area with the DOE G-1 aircraft and at strategically located ground sites so as to study the evolution of urban aerosols as they age and mix with biogenic SOA precursors. The NASA B-200 aircraft, equipped with the High Spectral Resolution Lidar (HSRL), digital camera, and the Research Scanning Polarimeter (RSP), will be flown in coordination with the G-1 to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties, and to provide the vertical context for the G-1 and ground in situ measurements.

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-07-12T23:59:59.000Z

7

Carbonaceous Aerosols and Radiative Effects Study (CARES), g1-aircraft, sedlacek sp2  

DOE Data Explorer (OSTI)

The primary objective of the Carbonaceous Aerosol and Radiative Effects Study (CARES) in 2010 was to investigate the evolution of carbonaceous aerosols of different types and their optical and hygroscopic properties in central California, with a focus on the Sacramento urban plume.

Sedlacek, Art

8

Cataractogenic effects of proton radiation  

E-Print Network (OSTI)

of proton radiation damage. The purpose of this study was (1) to determine the relative cataractogenic effects of different proton en- ergies, (2) to determine the relative cataractogenic effects of different radiation doses and (3) to determine... Laboratory in 1945 and 1946. Ten victims were exposed to various doses of moderately fast neutrons and hard gamma rays. In the eight survivors, two radiation cataracts resulted (15). In 1948 it was reported that five nuclear physicists with a common...

Kyzar, James Ronald

2012-06-07T23:59:59.000Z

9

Rotationally resolved Fano effect of HI molecules: An experimental study using coherent vacuum-ultraviolet radiation  

Science Journals Connector (OSTI)

An experiment studying the influence of molecular rotation in HI on photoelectron-spin polarization is presented. The experiment is highly wavelength selective since a laser-based vacuum-ultraviolet-radiation source with a bandwidth of 0.5×10-4 nm is applied to produce circularly polarized light. Although in the Fano effect the kinetic energy of the photoelectrons is not analyzed, rotational structure is resolved via narrow-band excitation of autoionization resonances. The photoelectron-spin polarization is found to be strongly affected by the rotational substructure, leading to changes in both magnitude and sign for different rotational lines.

T. Huth-Fehre; A. Mank; M. Drescher; N. Böwering; U. Heinzmann

1990-01-22T23:59:59.000Z

10

A study of radiation damage effects on the magnetic structure of bulk Iron  

SciTech Connect

Defects, defect interactions, and defect dynamics in solids created by fast neutrons are known to have significant impact on the performance and lifetime of structural materials. A fundamental understanding of the radiation damage effects in solids is therefore of great importance in assisting the development of improved materials - materials with ultrahigh strength, toughness, and radiation resistance. In this presentation, we show our recent theoretical investigation on the magnetic structure evolution of bulk iron in the region of the radiation defects. We applied a linear scaling ab-initio method based on density functional theory with local spin density approximation, namely the locally self-consistent multiple scattering method (LSMS), to the study of magnetic moment distributions in a cascade at the damage peak and for a series of time steps as the interstitials and vacancies recombined. Atomic positions correspond to those in a low energy cascade in a 10|000 atom sample, in which the primary damage state and the evolution of all defects produced were simulated using molecular dynamics with empirical, embedded-atom inter-atomic potentials. We will discuss how a region of affected moments expands and then recedes in response to a cascade evolution.

Wang Yang [Pittsburgh Supercomputing Center, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Nicholson, D. M. C.; Stocks, G. M.; Rusanu, Aurelian; Eisenbach, Markus; Stoller, R. E. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2011-04-01T23:59:59.000Z

11

Radiation effects on humans  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation effects on humans Radiation effects on humans Name: Joe Kemna Location: N/A Country: N/A Date: N/A Question: I am trying to find information on radiation. I need the effects on humans, the damage it causes to the environment, and any extra information you might have on the subject. Thank you for your time. Replies: Your library should be a good place to start, but first you need to narrow your question a bit. "Radiation" means radio waves, heat, light (including the ultraviolet light that causes suntan and sunburn), and what's called "ionizing radiation." By far the major source of the first three is the Sun, while the last I believe comes principally from cosmic rays and various naturally radioactive elements like uranium and radon. The most significant manmade sources of exposure would --- I think --- be household wiring and appliances (radio), engines and heating devices (heat), lamps (light), and X-ray machines, flying at high altitude in airplanes, and living in well-insulated homes built over radon sources (ionizing radiation). Heat, light and ionizing radiation play vital roles in the ecology of the Earth. Radio, light (in particular "tanning" ultraviolet), and ionizing radiation have all been widely assumed at different times to be particularly good or particularly bad for human health. Some recent issues of public concern have been the effect of radio waves from electric transmission lines, the effect on skin cancer incidence from tanning and sunburns, the depletion of the ultraviolet-light-produced ozone in the upper atmosphere by chlorofluorocarbons (CFCs), "global warming" from the increased absorption of heat radiation from the surface by atmospheric carbon dioxide and methane, and the effect of a long exposure to low levels of ionizing radiation as for example the people of Eastern Europe are experiencing from the Chernobyl nuclear power plant accident.

12

Overview of the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES)  

SciTech Connect

Substantial uncertainties still exist in the scientific understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transformation of atmospheric aerosol and the resulting impact on climate change. The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program's Carbonaceous Aerosol and Radiative Effects Study (CARES) carried out in June 2010 in Central Valley, California, was a comprehensive effort designed to improve this understanding. The primary objective of the field study was to investigate the evolution of secondary organic and black carbon aerosols and their climate-related properties in the Sacramento urban plume as it was routinely transported into the forested Sierra Nevada foothills area. Urban aerosols and trace gases experienced significant physical and chemical transformations as they mixed with the reactive biogenic hydrocarbons emitted from the forest. Two heavily-instrumented ground sites - one within the Sacramento urban area and another about 40 km to the northeast in the foothills area - were set up to characterize the evolution of meteorological variables, trace gases, aerosol precursors, aerosol size, composition, and climate-related properties in freshly polluted and 'aged' urban air. On selected days, the DOE G-1 aircraft was deployed to make similar measurements upwind and across the evolving Sacramento plume in the morning and again in the afternoon. The NASA B-200 aircraft, carrying remote sensing instruments, was also deployed to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties within and around the plume. This overview provides: a) the scientific background and motivation for the study, b) the operational and logistical information pertinent to the execution of the study, c) an overview of key observations and initial results from the aircraft and ground-based sampling platforms, and d) a roadmap of planned data analyses and focused modeling efforts that will facilitate the integration of new knowledge into improved representations of key aerosol processes in climate models.

Zaveri, Rahul A.; Shaw, William J.; Cziczo, D. J.; Schmid, Beat; Ferrare, R.; Alexander, M. L.; Alexandrov, Mikhail; Alvarez, R. J.; Arnott, W. P.; Atkinson, D.; Baidar, Sunil; Banta, Robert M.; Barnard, James C.; Beranek, Josef; Berg, Larry K.; Brechtel, Fred J.; Brewer, W. A.; Cahill, John F.; Cairns, Brian; Cappa, Christopher D.; Chand, Duli; China, Swarup; Comstock, Jennifer M.; Dubey, Manvendra K.; Easter, Richard C.; Erickson, Matthew H.; Fast, Jerome D.; Floerchinger, Cody; Flowers, B. A.; Fortner, Edward; Gaffney, Jeffrey S.; Gilles, Mary K.; Gorkowski, K.; Gustafson, William I.; Gyawali, Madhu S.; Hair, John; Hardesty, Michael; Harworth, J. W.; Herndon, Scott C.; Hiranuma, Naruki; Hostetler, Chris A.; Hubbe, John M.; Jayne, J. T.; Jeong, H.; Jobson, Bertram T.; Kassianov, Evgueni I.; Kleinman, L. I.; Kluzek, Celine D.; Knighton, B.; Kolesar, K. R.; Kuang, Chongai; Kubatova, A.; Langford, A. O.; Laskin, Alexander; Laulainen, Nels S.; Marchbanks, R. D.; Mazzoleni, Claudio; Mei, F.; Moffet, Ryan C.; Nelson, Danny A.; Obland, Michael; Oetjen, Hilke; Onasch, Timothy B.; Ortega, Ivan; Ottaviani, M.; Pekour, Mikhail S.; Prather, Kimberly A.; Radney, J. G.; Rogers, Ray; Sandberg, S. P.; Sedlacek, Art; Senff, Christoph; Senum, Gunar; Setyan, Ari; Shilling, John E.; Shrivastava, ManishKumar B.; Song, Chen; Springston, S. R.; Subramanian, R.; Suski, Kaitlyn; Tomlinson, Jason M.; Volkamer, Rainer M.; Wallace, Hoyt A.; Wang, J.; Weickmann, A. M.; Worsnop, Douglas R.; Yu, Xiao-Ying; Zelenyuk, Alla; Zhang, Qi

2012-08-22T23:59:59.000Z

13

Chronic Low Dose Radiation Effects on Radiation Sensitivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Chronic Low Dose Radiation Effects on Radiation Sensitivity Chronic Low Dose Radiation Effects on Radiation Sensitivity and Chromosome Instability Induction in TK6 Cells Schwartz J.L. 1 , Jordan R. 1 , Slovic J. 1 , Moruzzi A. 1 , Kimmel R. 2 , and Liber, H.L. 3 1 University of Washington, Seattle, WA; 2 Fred Hutchinson Cancer Research Center, Seattle, WA; 3 Colorado State University, Fort Collins, Colorado There are a number of cell responses that can be detected after low dose radiation exposures including the adaptive response, low dose hypersensitivity, and induced genomic instability. The relationship between these different phenomena is unknown. In this study, we measured adaptive responses, low dose hypersensitivity, and induced genomic instability in a human B-lymphoblastoid cell model, TK6, where we could genetically modify radiation responses by either over-expression of BCL-2 or deletion of TP53. TK6

14

Transport and Mixing Patterns over Central California during the Carbonaceous Aerosol and Radiative Effects Study (CARES)  

SciTech Connect

We describe the synoptic and regional-scale meteorological conditions that affected the transport and mixing of trace gases and aerosols in the vicinity of Sacramento, California during June 2010 when the Carbonaceous Aerosol and Radiative Effects Study (CARES) was conducted. The meteorological measurements collected by various instruments deployed during the campaign and the performance of the chemistry version of the Weather Research and Forecasting model (WRF-Chem) are both discussed. WRF-Chem was run daily during the campaign to forecast the spatial and temporal variation of carbon monoxide emitted from 20 anthropogenic source regions in California to guide aircraft sampling. The model is shown to reproduce the overall circulations and boundary-layer characteristics in the region, although errors in the upslope wind speed and boundary-layer depth contribute to differences in the observed and simulated carbon monoxide. Thermally-driven upslope flows that transported pollutants from Sacramento over the foothills of the Sierra Nevada occurred every afternoon, except during three periods when the passage of mid-tropospheric troughs disrupted the regional-scales flow patterns. The meteorological conditions after the passage of the third trough were the most favorable for photochemistry and likely formation of secondary organic aerosols. Meteorological measurements and model forecasts indicate that the Sacramento pollutant plume was likely transported over a downwind site that collected trace gas and aerosol measurements during 23 periods; however, direct transport occurred during only eight of these periods. The model also showed that emissions from the San Francisco Bay area transported by intrusions of marine air contributed a large fraction of the carbon monoxide in the vicinity of Sacramento, suggesting that this source likely affects local chemistry. Contributions from other sources of pollutants, such as those in the Sacramento Valley and San Joaquin Valley, were relatively low. Aerosol layering in the free troposphere was observed during the morning by an airborne Lidar; WRF-Chem forecasts showed that mountain venting processes contributed to aged pollutants aloft in the valley atmosphere which then can be entrained into the growing boundary layer the subsequent day.

Fast, Jerome D.; Gustafson, William I.; Berg, Larry K.; Shaw, William J.; Pekour, Mikhail S.; Shrivastava, ManishKumar B.; Barnard, James C.; Ferrare, R.; Hostetler, Chris A.; Hair, John; Erickson, Matthew H.; Jobson, Tom; Flowers, Bradley; Dubey, Manvendra K.; Springston, Stephen R.; Pirce, Bradley R.; Dolislager, Leon; Pederson, J. R.; Zaveri, Rahul A.

2012-02-17T23:59:59.000Z

15

Transport and mixing patterns over Central California during the carbonaceous aerosol and radiative effects study (CARES)  

SciTech Connect

We describe the synoptic and regional-scale meteorological conditions that affected the transport and mixing of trace gases and aerosols in the vicinity of Sacramento, California during June 2010 when the Carbonaceous Aerosol and Radiative Effects Study (CARES) was conducted. The meteorological measurements collected by various instruments deployed during the campaign and the performance of the chemistry version of the Weather Research and Forecasting model (WRF-Chem) are both discussed. WRF-Chem was run daily during the campaign to forecast the spatial and temporal variation of carbon monoxide emitted from 20 anthropogenic source regions in California to guide aircraft sampling. The model is shown to reproduce the overall circulations and boundary-layer characteristics in the region, although errors in the upslope wind speed and boundary-layer depth contribute to differences in the observed and simulated carbon monoxide. Thermally-driven upslope flows that transported pollutants from Sacramento over the foothills of the Sierra Nevada occurred every afternoon, except during three periods when the passage of mid-tropospheric troughs disrupted the regional-scale flow patterns. The meteorological conditions after the passage of the third trough were the most favorable for photochemistry and likely formation of secondary organic aerosols. Meteorological measurements and model forecasts indicate that the Sacramento pollutant plume was likely transported over a downwind site that collected trace gas and aerosol measurements during 23 time periods; however, direct transport occurred during only eight of these periods. The model also showed that emissions from the San Francisco Bay area transported by intrusions of marine air contributed a large fraction of the carbon monoxide in the vicinity of Sacramento, suggesting that this source likely affects local chemistry. Contributions from other sources of pollutants, such as those in the Sacramento Valley and San Joaquin Valley, were relatively low. Aerosol layering in the free troposphere was observed during the morning by an airborne Lidar. WRF-Chem forecasts showed that mountain venting processes contributed to aged pollutants aloft in the valley atmosphere that are then entrained into the growing boundary layer the subsequent day.

Fast J. D.; Springston S.; Gustafson Jr., W. I.; Berg, L. K.; Shaw, W. J.; Pekour, M.; Shrivastava, M.; Barnard, J. C.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. A.; Erickson, M.; Jobson, B. T.; Flowers, B.; Dubey, M. K.; Pierce, R. B.; Dolislager, L.; Pederson, J.; Zaveri, R. A.

2012-02-17T23:59:59.000Z

16

Japan Program: Radiation Effects Research Foundation | Department...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The Life Span Study is the major RERF epidemiologic study that generates data on cancer incidence, cancer mortality, and non-cancer effects in relation to radiation dose. The...

17

Study of Interfacial Interactions Using Thing Film Surface Modification: Radiation and Oxidation Effects in Materials  

SciTech Connect

Interfaces play a key role in dictating the long-term stability of materials under the influence of radiation and high temperatures. For example, grain boundaries affect corrosion by way of providing kinetically favorable paths for elemental diffusion, but they can also act as sinks for defects and helium generated during irradiation. Likewise, the retention of high-temperature strength in nanostructured, oxide-dispersion strengthened steels depends strongly on the stoichiometric and physical stability of the (Y, Ti)-oxide particles/matrix interface under radiation and high temperatures. An understanding of these interfacial effects at a fundamental level is important for the development of materials for extreme environments of nuclear reactors. The goal of this project is to develop an understanding stability of interfaces by depositing thin films of materials on substrates followed by ion irradiation of the film-substrate system at elevated temperatures followed by post-irradiation oxidation treatments. Specifically, the research will be performed by depositing thin films of yttrium and titanium (~500 nm) on Fe-12%Cr binary alloy substrate. Y and Ti have been selected as thin-film materials because they form highly stable protective oxides layers. The Fe-12%Cr binary alloy has been selected because it is representative of ferritic steels that are widely used in nuclear systems. The absence of other alloying elements in this binary alloy would allow for a clearer examination of structures and compositions that evolve during high-temperature irradiations and oxidation treatments. The research is divided into four specific tasks: (1) sputter deposition of 500 nm thick films of Y and Ti on Fe-12%Cr alloy substrates, (2) ion irradiation of the film-substrate system with 2MeV protons to a dose of 2 dpa at temperatures of 300°C, 500°C, and 700°C, (3) oxidation of as-deposited and ion-irradiated samples in a controlled oxygen environment at 500°C and 700°C, (4) multi-scale computational modeling involving first- principle molecular dynamics (FPMD) and coarse-grained dissipative particle dynamics (DPD) approaches to develop theories underlying the evolution and stability of structures and phases. Samples from Tasks 1 to 3 (above) will be rigorously characterized and analyzed using scanning electron microscopy, Auger electron microscopy, x-ray diffraction, Rutherford back scatter spectroscopy, and transmission electron microscopy. Expected outcomes of the experimental work include a quantitative understanding film-substrate interface mixing, evolution of defects and other phases at the interface, interaction of interfaces with defects, and the ability of the Y and Ti films to mitigate irradiation-assisted oxidation. The aforementioned experimental work will be closely coupled with multi-scale molecular dynamics (MD) modeling to understand the reactions at the surface, the transport of oxidant through the thin film, and the stabilities of the deposited thin films under radiation and oxidation. Simulations of materials property changes under conditions of radiation and oxidation require multiple size domains and a different simulation scheme for each of these domains. This will be achieved by coupling the FPMD and coarse-grained kinetic Monte Carlo (KMC). This will enable the comparison of the results of each simulation approach with the experimental results.

Sridharan, Kumar; Zhang, Jinsuo

2014-01-09T23:59:59.000Z

18

Fast-neutron radiation effects in a silica-core optical fiber studied by a CCD-camera spectrometer  

Science Journals Connector (OSTI)

A simple CCD-camera spectrometer was deployed at the Los Alamos Spallation Radiation Effects Facility to characterize fast-neutron irradiation effects in several silica-based optical...

Griscom, D L; Gingerich, M E; Friebele, E J; Putnam, M; Unruh, W

1994-01-01T23:59:59.000Z

19

Radiation-Induced Bystander Effects and Relevance to Human Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation-Induced Bystander Effects and Relevance to Human Radiation Radiation-Induced Bystander Effects and Relevance to Human Radiation Exposures Review of phenomenon appears in Radiation Research Pamela Sykes and Benjamin Blyth One concern of radiobiologists is the effect radiation exposure might have on nearby unirradiated cells. For example, when only a small fraction of cells are directly hit by radiation energy, are the surrounding unirradiated cells also at an increased risk of cancer? The term "radiation-induced bystander effect" is used to describe radiation-induced biological changes that occur in unirradiated cells within an irradiated cell population. Radiation-induced bystander effects have become established in the vernacular and are considered as an authentic radiation response. However, there is still no consensus on a precise definition of the term, which

20

Clouds in the atmospheres of extrasolar planets. IV. On the scattering greenhouse effect of CO2 ice particles: Numerical radiative transfer studies  

E-Print Network (OSTI)

Owing to their wavelengths dependent absorption and scattering properties, clouds have a strong impact on the climate of planetary atmospheres. Especially, the potential greenhouse effect of CO2 ice clouds in the atmospheres of terrestrial extrasolar planets is of particular interest because it might influence the position and thus the extension of the outer boundary of the classic habitable zone around main sequence stars. We study the radiative effects of CO2 ice particles obtained by different numerical treatments to solve the radiative transfer equation. The comparison between the results of a high-order discrete ordinate method and simpler two-stream approaches reveals large deviations in terms of a potential scattering efficiency of the greenhouse effect. The two-stream methods overestimate the transmitted and reflected radiation, thereby yielding a higher scattering greenhouse effect. For the particular case of a cool M-type dwarf the CO2 ice particles show no strong effective scattering greenhouse eff...

Kitzmann, D; Rauer, H

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Genetic studies at the Atomic Bomb Casualty Commission–Radiation Effects Research Foundation: 1946–1997  

Science Journals Connector (OSTI)

...inevitable, and studies to anticipate worker’s health hazards were undertaken. At that...data obtained by W. L. Russell at Oak Ridge (21, 22), yielding one of the lower estimates...in the course of the experiment at Oak Ridge occurred in the offspring of both...

James V. Neel

1998-01-01T23:59:59.000Z

22

Effect of ionizing radiation on the primate pancreas: an endocrine and morphologic study  

SciTech Connect

In this study we evaluated the endocrine, biochemical, and haematological derangements as well as pancreatic and histological changes of the bonemarrow in the primate following external fractionated subtotal marrow irradiation without bonemarrow reconstitution. The irradiation was administered in preparation for pancreatic transplantation. Two groups of animals (ten in each group) received 800 rad (8 Gy) and 1000 rad (10 Gy) respectively over 4 to 5 weeks. A maximum of 200 rads (2 Gy) were administered weekly as photons from a 6 MV linear accelerator. During irradiation the animals remained normoglycaemic in the presence of transiently elevated liver enzymes and serum amylase values, which returned to normal on completion of the irradiation. Insulin release was significantly reduced in both groups during irradiation and was associated with minimally decreased K-values in the presence of mild glucose intolerance. Pancreatic light morphologic changes included structural changes of both exocrine and endocrine elements and included necrosis of the islet cells and acinar tissue. Islet histology demonstrated striking cytocavitary network changes of alpha and beta cells, including degranulation, vacuolization, mitochondrial destruction, and an increase in lysosomes. A hypoplastic bonemarrow ranging from moderate to severe was observed in all irradiated recipients. Near total fractionated body irradiation in the primate is therefore associated with elevated liver enzymes, pancytopenia, transient hyperamylasaemia, hypoinsulinaemia, a varying degree of pancreatitis, and bonemarrow hypoplasia.

Du Toit, D.F.; Heydenrych, J.J.; Smit, B.; Zuurmond, T.; Louw, G.; Laker, L.; Els, D.; Weideman, A.; Wolfe-Coote, S.; Du Toit, L.B.

1987-01-01T23:59:59.000Z

23

Synchrotron radiation studies of the  

Science Journals Connector (OSTI)

Two questions thought to have a significant effect on SiC-MOS device characteristics are treated. The existence of carbon clusters or carbon containing by-products and the existence of sub-oxides at the SiO2/SiC interface. Results of photoemission studies using synchrotron radiation of the interface of the Si-terminated surface of n-type SiC(0001) crystals are presented. The results show that no carbon clusters or carbon containing by-product can be detected at the interface of in situ or ex situ grown samples with an oxide layer thickness larger than  Å. The presence of sub-oxides at the SiO2/SiC interface was predicted in a theoretical calculation and has been revealed in Si 2p core level data by several groups. These results were not unanimous; significant differences in the number of sub-oxide and shifts were reported. A study also including the Si 1s core level and Si KLL Auger transitions was therefore made. These data show the presence of only one sub-oxide at the interface, assigned to Si1+ oxidation states. The SiO2 chemical shift is shown to exhibit a dependence on oxide thickness, similar to but smaller in magnitude than the thickness dependence earlier revealed for SiO2/Si.

L I Johansson; C Virojanadara

2004-01-01T23:59:59.000Z

24

RADIATION EFFECTS IN MATERIAL MICROSTRUCTURE.  

SciTech Connect

Next generation nuclear power systems, high-power particle accelerators and space technology will inevitably rely on higher performance materials that will be able to function in the extreme environments of high irradiation, high temperatures, corrosion and stress. The ability of any material to maintain its functionality under exposure to harsh conditions is directly linked to the material structure at the nano- and micro-scales. Understanding of the underlying processes is key to the success of such undertakings. This paper presents experimental results of the effects of radiation exposure on several unique alloys, composites and crystals through induced changes in the physio-mechanical macroscopic properties.

SIMOS,N.

2007-05-30T23:59:59.000Z

25

Radiation effects in the environment  

SciTech Connect

Although the Navajo possess substantial resource wealth-coal, gas, uranium, water-this potential wealth has been translated into limited permanent economic or political power. In fact, wealth or potential for wealth has often made the Navajo the victims of more powerful interests greedy for the assets under limited Navajo control. The primary focus for this education workshop on the radiation effects in the environment is to provide a forum where scientists from the nuclear science and technology community can share their knowledge toward the advancement and diffusion of nuclear science and technology issues for the Navajo public. The scientists will make an attempt to consider the following basic questions; what is science; what is mathematics; what is nuclear radiation? Seven papers are included in this report: Navajo view of radiation; Nuclear energy, national security and international stability; ABC`s of nuclear science; Nuclear medicine: 100 years in the making; Radon in the environment; Bicarbonate leaching of uranium; and Computational methods for subsurface flow and transport. The proceedings of this workshop will be used as a valuable reference materials in future workshops and K-14 classrooms in Navajo communities that need to improve basic understanding of nuclear science and technology issues. Results of the Begay-Stevens research has revealed the existence of strange and mysterious concepts in the Navajo Language of nature. With these research results Begay and Stevens prepared a lecture entitled The Physics of Laser Fusion in the Navajo language. This lecture has been delivered in numerous Navajo schools, and in universities and colleges in the US, Canada, and Alaska.

Begay, F.; Rosen, L.; Petersen, D.F.; Mason, C.; Travis, B. [Los Alamos National Lab., NM (United States); Yazzie, A. [Navajo Nation, Window Rock, AZ (United States). Dept. of History; Isaac, M.C.P.; Seaborg, G.T. [Lawrence Berkeley National Lab., CA (United States); Leavitt, C.P. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Physics and Astronomy

1999-04-01T23:59:59.000Z

26

Low Dose Radiation Research Program: Low Dose Radiation Effects in  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation Effects in Differentiating Human Lens Cells Radiation Effects in Differentiating Human Lens Cells E.A. Blakely1, M.P. McNamara1, P.Y. Chang1, K.A. Bjornstad1, D. Sudar1, and A.C. Thompson2 1Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California; 2Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, California. Introduction The human lens is one of the most radiosensitive organs of the body. Cataract, the opacification of the lens, is a late-appearing response to radiation damage. There are few data available on the late radiation effects of exposure in space flight to charged particle beams, the most prevalent of which are protons. Basic research in this area is needed to integrate the responses of both critical and other representative tissues

27

Radiative Effects of Cloud Inhomogeneity and  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiative Effects of Cloud Inhomogeneity and Geometric Association Over the Tropical Western Pacific Warm Pool X. Wu National Center for Atmospheric Research (a) Boulder, Colorado...

28

Ion Beams - Radiation Effects Facility / Cyclotron Institute...  

NLE Websites -- All DOE Office Websites (Extended Search)

Ion Beams Available Beams Beam Change Times Measurements Useful Graphs Various ion beams have been developed specifically for the Radiation Effects Facility. These beams...

29

Posters The Effects of Radiative Transfer  

NLE Websites -- All DOE Office Websites (Extended Search)

Posters The Effects of Radiative Transfer on Low-Level Cyclogenesis M. J. Leach and S. Raman Department of Marine, Earth and Atmospheric Sciences North Carolina State University Raleigh, North Carolina Introduction Many investigators have documented the role that thermodynamic forcing due to radiative flux divergence plays in the enhancement or generation of circulation. Most of these studies involve large-scale systems (e.g., Slingo et al. 1988), small-scale systems such as thunderstorms (Chen and Cotton 1988), and squall lines (Chin, submitted). The generation of circulation on large scales results from the creation of divergence in the upper troposphere and the maintenance of low-level potentially unstable air, and the maintenance of baroclinicity throughout

30

Experimental study of the effect of electromagnetic microwave radiation on parts made of high-energy polymer materials  

Science Journals Connector (OSTI)

Results of experimental measurements of Young’s modulus, burning rate, and specific heat of condensed high-energy polymer compositions (solid propellants) subjected to microwave radiation are reported. Experim...

L. L. Khimenko; A. P. Rybakov; N. A. Rybakov…

2014-07-01T23:59:59.000Z

31

Data Room - Facilities - Radiation Effects Facility / Cyclotron...  

NLE Websites -- All DOE Office Websites (Extended Search)

radiation effects beam - line. Cable passage to beam line. In addition to a 18 port bnc patch panel connecting the data room and beam line area, there are also a series of...

32

Radiation Effects in Fission and Fusion Reactors  

Science Journals Connector (OSTI)

Since the prediction of “Wigner disease” [1...] and the subsequent observation of anisotropic growth of the graphite used in the Chicago Pile, the effects of radiation on materials has been an important technolog...

G. Robert Odette; Brian D. Wirth

2005-01-01T23:59:59.000Z

33

Radiation Effects Research Foundation Links Past and Future ...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Radiation Effects Research Foundation Links Past and Future Radiation Effects Research Foundation Links Past and Future August 2009 This document provides historical information...

34

Effect of radiation on the response of dental pulp to operative and endodontic procedures: an experimental study  

SciTech Connect

Thirty-six 56-day-old male Sprague-Dawley albino rats served as two groups of experimental animals. Group 1 was irradiated with 400 rads delivered as total-body radiation from a cesium source. Group 2 served as the control group and was not irradiated. Three weeks later, the dental microscope was used to facilitate various dental procedures in both groups of animals (cavity preparation filled with zinc oxide-eugenol, pulp exposure capped with zinc oxide-eugenol, and pulp exposure left open). Two animals for each procedure from Groups 1 and 2 were killed at time intervals of 2, 4, and 8 weeks. The results showed that (1) radiation at this dose resulted in a depression of the normal response of the dental pulp to the trauma and infection induced by pulpal exposure, (2) there were no pathologic changes in the untreated molars of the irradiated animals, and (3) the use of the dental microscope greatly facilitated cavity preparation in the molars of rats.

Fawzi, M.I.; Shklar, G.; Krakow, A.A.

1985-04-01T23:59:59.000Z

35

Three-dimensional, two-species magnetohydrodynamic studies of the early time behaviors of the Combined Release and Radiation Effects Satellite G2 barium release  

SciTech Connect

We present a three-dimensional, two-species (Ba{sup +} and H{sup +}) MHD model to study the early time behaviors of a barium release at about 1 R{sub E} like Combined Release and Radiation Effects Satellite G2, with emphasis placed on the three-dimensional evolution of the barium cloud and its effects on the ambient plasma environment. We find that the perturbations caused by the cloud are the combined results of the initial injection, the radial expansion, and the diamagnetic effect and propagate as fast MHD waves in the magnetosphere. In return, the transverse expansion and the cross-B motion of barium ions are constrained by the magnetic force, which lead to a field-aligned striation of ions and the decoupling of these ions from the neutrals. Our simulation shows the formation and collapse of the diamagnetic cavity in the barium cloud. The estimated time scale for the cavity evolution might be much shorter if photoionization time scale and field aligned expansion of barium ions are considered. In addition, our two species MHD simulation also finds the snowplow effect resulting from the momentum coupling between barium ions and background H{sup +}, which creates density hole and bumps in the background H{sup +} when barium ions expanding along the magnetic field lines.

Xie, Lianghai, E-mail: xielh@nssc.ac.cn; Li, Lei; Wang, Jingdong; Zhang, Yiteng [Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190 (China)] [Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190 (China)

2014-04-15T23:59:59.000Z

36

Study of Ultraviolet Radiation and Genotoxic Effects of Natural Sunlight in Relation to Skin Cancer in Saudi Arabia  

Science Journals Connector (OSTI)

...supplied by the Solar Light Company, Philadelphia...UV meter measures energy between 290 and 320...sunlight varies with solar angle and atmospheric...1983. The effective energy of a sunburn unit...the International Solar Energy Society Congress...

Mohammed A. Hannan; Manik Paul; Magid H. Amer; and Farouk H. Al-Watban

1984-05-01T23:59:59.000Z

37

Effect of multiple scattering on Cerenkov radiation from energetic electrons  

SciTech Connect

Cerenkov radiation can be used as a diagnostic tool to study energetic electrons generated in ultra-intense laser matter interactions. However, electrons suffer scattering with nuclei as they move in a medium. In this article, we theoretically study the effect of multiple scattering on Cerenkov radiation, and obtain analytical formulas under some circumstances. The results show that when the speed of an energetic electron is not close to the light speed in the medium, Cerenkov radiation is just slightly decreased due to multiple scattering. In the case that the electron speed is very close to the light speed in the medium, the effect of multiple scattering becomes significant, and the radiation is dominated by bremsstrahlung.

Zheng Jian [CAS Key Laboratory of Basic Plasma Physics and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2013-01-15T23:59:59.000Z

38

Contrasting the direct radiative effect and direct radiative forcing of aerosols  

E-Print Network (OSTI)

The direct radiative effect (DRE) of aerosols, which is the instantaneous radiative impact of all atmospheric particles on the Earth's energy balance, is sometimes confused with the direct radiative forcing (DRF), which ...

Heald, Colette L.

39

Effects of radiation on materials: twelfth international symposium  

SciTech Connect

This publication provides information on irradiation creep of structural metals; microstructural development, neutron-induced swelling and charged particle irradiation. The theory of swelling is discussed along with mechanical properties, pressure vessel steels and irradiation facilities. The influence of helium on radiation-induced microstructural development, and radiation-induced changes in fracture toughness of iron-based austenitic and ferrite alloys are presented. The final section on other radiation studies covers the following: a modified method of helium introduction into alloys via the tritium trick, radiation damage aspects of a novel method for providing safe storage of Krypton-85 from fuel re-processing, and radiation effects on resins and zeolites forming part of the waste stream from the clean-up effort at the Three Mile Island Nuclear Plant.

Garner, F.A. (ed.); Perrin, J.S. (ed)

1984-06-01T23:59:59.000Z

40

Atmospheric Radiation Measurement (ARM) Data from Shouxian, China for the Study of Aerosol Indirect Effects in China  

DOE Data Explorer (OSTI)

In a complex ARM Mobile Facility (AMF) deployment, monitoring data was collected at four locations in China during 2008. The various sites are located in regions with different climate regimes and with high aerosol loadings of different optical, physical, and chemical properties. Measurements obtained at all the AMF sites during the 8-month deployment in China will help scientists to validate satellite-based findings, understand the mechanisms of the aerosol indirect effects in the region, and examine the roles of aerosols in affecting regional climate and atmospheric circulation, with a special focus on the impact of the East Asian monsoon system. As with other collections from the ARM Mobile Facility, the datasets are available from the ARM Archive. The ARM Archive physically resides at the Oak Ridge National Laboratory.

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Effects of Solar UV Radiation on Morphology and Photosynthesis of Filamentous Cyanobacterium Arthrospira platensis  

Science Journals Connector (OSTI)

...ECOLOGY Effects of Solar UV Radiation on Morphology and Photosynthesis...study the impact of solar UV radiation (UVR) (280 to 400 nm) on...Ink and Chemicals, Tokyo, Japan. 12 Dismukes, G. C., V...Effects of solar and ultraviolet radiation on motility, photomovement...

Hongyan Wu; Kunshan Gao; Virginia E. Villafañe; Teruo Watanabe; E. Walter Helbling

2005-09-01T23:59:59.000Z

42

Radiation effects on corrosion of zirconium alloys  

SciTech Connect

From the wide use of zirconium alloys as components in nuclear reactors, has come clear evidence that reactor radiation is a major corrosion parameter. The evidence emerges from comparisons of zirconium alloy corrosion behavior in different reactor types, for example, BWRs versus PWRs and in corresponding reactor loop chemistries; also, oxidation rates differ with location along components such as fuel rods and reactor pressure tubes. In most respects, oxidation effects on power reactor components are paralleled by oxidation behavior on specimens exposed to radiation in reactor loops.

Johnson, A.B. Jr.

1989-06-01T23:59:59.000Z

43

Memory effects in radiative jet energy loss  

E-Print Network (OSTI)

In heavy-ion collisions the created quark-gluon plasma forms a quickly evolving background, leading to a time dependent radiative behavior of high momentum partons traversing the medium. We use the Schwinger Keldysh formalism to describe the jet evolution as a non-equilibrium process including the Landau-Pomeranschuk-Migdal effect. Concentrating on photon emission, a comparison of our results to a quasistatic calculation shows good agreement, leading to the conclusion that the radiative behavior follows the changes in the medium almost instantaneously.

Frank Michler; Björn Schenke; Carsten Greiner

2009-05-18T23:59:59.000Z

44

Effects of Radiation on Adaptive Immunity: Contact Hypersensitivity Model  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation on Adaptive Immunity: Contact Hypersensitivity Model Radiation on Adaptive Immunity: Contact Hypersensitivity Model Gregory Nelson Loma Linda University Abstract It has long been appreciated that cells of the immune system are radiosensitive and use apoptosis as the primary mechanism of cell death following injury. The hypervariability of the immunoglobulin superfamily of genes expressed in lymphoid cells also led to the appreciation of the nonhomologous end joining mechanism of DNA repair. Clinically, whole body irradiation is used in treatment of some lymphomas and as an immunosuppressive agent for bone marrow transplants. Inflammation at sites of radiotherapy is a common side effect. Many studies with radiation have addressed the changes in cell populations following radiation exposure and have shown a reproducible pattern of relative sensitivities amongst

45

Effects of ionizing radiation on modern ion exchange materials  

SciTech Connect

We review published studies of the effects of ionizing radiation on ion exchange materials, emphasizing those published in recent years. A brief overview is followed by a more detailed examination of recent developments. Our review includes styrene/divinylbenzene copolymers with cation-exchange or anion-exchange functional groups, polyvinylpyridine anion exchangers, chelating resins, multifunctional resins, and inorganic exchangers. In general, strong-acid cation exchange resins are more resistant to radiation than are strong-base anion exchange resins, and polyvinylpyridine resins are more resistant than polystyrene resins. Cross-linkage, salt form, moisture content, and the surrounding medium all affect the radiation stability of a specific exchanger. Inorganic exchangers usually, but not always, exhibit high radiation resistance. Liquid ion exchangers, which have been used so extensively in nuclear processing applications, also are included.

Marsh, S.F.; Pillay, K.K.S.

1993-10-01T23:59:59.000Z

46

Studies about Space Radiation Promote New Fields in Radiation Biology  

Science Journals Connector (OSTI)

......the ISS will depend on economical conditions. OUR GOAL...Study in the effects of solar ultraviolet light (UV-B...billion years ago by solar ultraviolet light. At...layer. Therefore, the energy from solar UV was stronger than......

Takeo Ohnishi; Akihisa Takahashi; Ken Ohnishi

2002-12-01T23:59:59.000Z

47

Radiation Effects in the Space Telecommunications Environment  

SciTech Connect

Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space.

Fleetwood, Daniel M.; Winokur, Peter S.

1999-05-17T23:59:59.000Z

48

Study on great northern beans (Phaseolus vulgaris): effect of drum drying process on bean flour properties and effect on gamma radiation on bean starch properties  

SciTech Connect

Great Northern bean (Phaseolus vulgaris L.) drum dried flours at native pH of 6.54, pH 6 and 7 showed reduced activities of trypsin inhibitor, ..cap alpha..-amylase inhibitor, hemagglutinating titer, and nitrogen solubility. Electrophoretic analyses showed a slight modification of the native bean proteins, and the presence of at least four trypsin inhibitors. The study of the effect of 2.5-20 kGy irradiation doses on Great Northern beans showed essentially no modification of the electrophoretic mobility of the storage proteins or the trypsin inhibitors. Nitrogen solubility and hemagglutinating activity were essentially unchanged. With the 20 kGy dose, decrease in ..cap alpha..-amylase inhibitor activity, decrease reactive/available lysine content, and decrease cooking time of the irradiated beans after 11 months of storage were observed. Taste panel results indicated that the control and 20 kGy irradiated bean were significantly different at 5% level. At 20 kGy dose, the beans developed a partially water soluble brown color.

Rayas-Solis, P.

1988-01-01T23:59:59.000Z

49

Silver Clear Nylon Dressing is Effective in Preventing Radiation-Induced Dermatitis in Patients With Lower Gastrointestinal Cancer: Results From a Phase III Study  

SciTech Connect

Purpose: For patients with anal canal and advanced rectal cancer, chemoradiation therapy is a curative modality or an important adjunct to surgery. Nearly all patients treated with chemoradiation experience some degree of radiation-induced dermatitis (RID). Prevention and effective treatment of RID, therefore, is of considerable clinical relevance. The present phase III randomized trial compared the efficacy of silver clear nylon dressing (SCND) with that of standard skin care for these patients. Methods and Materials: A total of 42 rectal or anal canal cancer patients were randomized to either a SCND or standard skin care group. SCND was applied from Day 1 of radiation therapy (RT) until 2 weeks after treatment completion. In the control arm, sulfadiazine cream was applied at the time of skin dermatitis. Printed digital photographs taken 2 weeks prior to, on the last day, and two weeks after the treatment completion were scored by 10 blinded readers, who used the common toxicity scoring system for skin dermatitis. Results: The radiation dose ranged from 50.4 to 59.4 Gy, and there were no differences between the 2 groups. On the last day of RT, when the most severe RID occurs, the mean dermatitis score was 2.53 (standard deviation [SD], 1.17) for the standard and 1.67 (SD, 1.2; P=.01) for the SCND arm. At 2 weeks after RT, the difference was 0.39 points in favor of SCND (P=.39). There was considerable intraclass correlation among the 10 observers. Conclusions: Silver clear nylon dressing is effective in reducing RID in patients with lower gastrointestinal cancer treated with combined chemotherapy and radiation treatment.

Niazi, Tamim M. [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada)] [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Vuong, Te, E-mail: tvuong@jgh.mcgill.ca [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada)] [Segal Cancer Centre, Department of Radiation Oncology, Jewish General Hospital, McGill University (Canada); Azoulay, Laurant [Department of Epidemiology, Jewish General Hospital, McGill University (Canada)] [Department of Epidemiology, Jewish General Hospital, McGill University (Canada); Marijnen, Corrie [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands)] [Department of Clinical Oncology, Leiden University Medical Center, Amsterdam (Netherlands); Bujko, Kryzstof [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland)] [Department of Radiotherapy, The Maria Sklodowska-Curie Memorial Cancer Centre, Warsaw (Poland); Nasr, Elie [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon)] [Department of Radiation Oncology, Hotel-Dieu de France Hospital (Lebanon); Lambert, Christine; Duclos, Marie; Faria, Sergio; David, Marc [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada)] [Department of Radiation Oncology, Montreal-General-Hospital, McGill University, Montreal (Canada); Cummings, Bernard [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto (Canada)

2012-11-01T23:59:59.000Z

50

Technical Note: Estimating Aerosol Effects on Cloud Radiative Forcing  

SciTech Connect

Estimating anthropogenic aerosol effects on the planetary energy balance through the aerosol influence on clouds using the difference in cloud radiative forcing from simulations with and without anthropogenic emissions produces estimates that are positively biased. A more representative method is suggested using the difference in cloud radiative forcing calculated with aerosol radiative effects neglected. The method also yields an aerosol radiative forcing decomposition that includes a term quantifying the impact of changes in surface albedo. The method requires only two additional diagnostic calculations: the whole-sky and clear-sky top-of-atmosphere radiative flux with aerosol radiative effects neglected.

Ghan, Steven J.

2013-10-09T23:59:59.000Z

51

Effect of nuclear radiation on the elastic moduli of zircon  

Science Journals Connector (OSTI)

Zircon crystals that have been damaged by a naturally occurring radioactive contaminant referred to as metamict zircons have density values ranging from 4.70 to 3.90 g/cm3. The present work is a study of the effect of the damage on the single?crystal elastic moduli. A systematic and very marked decrease (i.e. up to 69%) of the elastic moduli with density have been observed. All the longitudinal and the shear elastic moduli decrease with radiation damage and approach two common saturation values of 1.5×1012 and 0.49×1012 dyn/cm2 respectively. Present observation of the elastic moduli of the radiation?damaged zircon crystals confirms Warren’s theoretical predictions concerning the effect of different pore geometries on the compressibility. Qualitative correlation of the elastic moduli with the structural changes arising from radiation damage in zircon crystals suggests that the marked decrease of the elastic moduli in the radiation?damaged zircons is caused by the nonspherical defect clusters microcracks and pores generated during radiation damage. Thermal annealing x?ray diffraction elastic moduli and density measurements on the zircon samples confirm the ’’three?stage’’ process proposed for the metamict transformation of zircons but the final product of metamictization does not seem to be a mixture of ZrO2 and SiO2 crystallites.

Hüsnü Özkan

1976-01-01T23:59:59.000Z

52

Radiation damage effects on detectors and eletronic devices in harsh radiation environment  

E-Print Network (OSTI)

Radiation damage effects represent one of the limits for technologies to be used in harsh radiation environments as space, radiotherapy treatment, high-energy phisics colliders. Different technologies have known tolerances to different radiation fields and should be taken into account to avoid unexpected failures which may lead to unrecoverable damages to scientific missions or patient health.

Fiore, S

2015-01-01T23:59:59.000Z

53

Solid low-level radioactive waste radiation stability studies  

E-Print Network (OSTI)

properties and condition; on the other, on the specific features of thermal and radiation influences on it (Spitsyn et al. 1983). For the average composition of the fission products going to wastes repositories, the mean energy of irradiation may vary from... to the container determines, in part, the life of the container. Cormsion studies of containers by solidified wastes has indicated no problem areas in limited measurements to date; however very long-term effects have not been evaluated. The useful life...

Williams, Arnold Andre?

1989-01-01T23:59:59.000Z

54

A Global Climatology of Outgoing Longwave Spectral Cloud Radiative Effect and Associated Effective Cloud Properties  

Science Journals Connector (OSTI)

Longwave (LW) spectral flux and cloud radiative effect (CRE) are important for understanding the earth’s radiation budget and cloud–radiation interaction. Here, the authors extend their previous algorithms to collocated Atmospheric Infrared ...

Xianglei Huang; Xiuhong Chen; Gerald L. Potter; Lazaros Oreopoulos; Jason N. S. Cole; Dongmin Lee; Norman G. Loeb

2014-10-01T23:59:59.000Z

55

Japan Program - Radiation Effects Research Foundation (RERF)  

NLE Websites -- All DOE Office Websites (Extended Search)

Safety Safety Home Sub Offices › Worker Safety & Health Policy › Worker Safety & Health Assistance › Illness & Injury Prevention Programs › International Health Studies › Office of Worker Screening and Compensation Support Mission & Functions › Health & Safety › Worker Safety & Health Policy › Worker Safety & Health Assistance › Illness & Injury Prevention Programs › International Health Studies › Worker Screening and Compensation Support Federal Line Management Oversight of DOE Nuclear Facilities Integrated Safety Management (ISM) A-Z Index Directory OSH Regulatory and Policy Response Line Health Resources Policy and Standards Worker Safety Beryllium Chemical Safety Biological Safety Radiation Safety Rules 10 CFR 707 10 CFR 835

56

Experimental and Computational Studies of Electric Thruster Plasma Radiation Emission  

E-Print Network (OSTI)

Experimental and Computational Studies of Electric Thruster Plasma Radiation Emission Murat Celik Thruster Plasma Radiation Emission by Murat C¸elik B.S., Aerospace Engineering and Physics, University;Experimental and Computational Studies of Electric Thruster Plasma Radiation Emission by Murat C¸elik Submitted

57

Radiation Effects on Metastable States of Superheated Water.  

E-Print Network (OSTI)

??Radiation Effects on Metastable States of Superheated Water covers theory, application, and experimentation into the behavior of water at temperatures above the boiling point. The… (more)

Alvord, Charles William

2008-01-01T23:59:59.000Z

58

Author Ziegler, Susan Benner, Ronald Title Effects of solar radiation ...  

Science Journals Connector (OSTI)

Author Ziegler, Susan Benner, Ronald Title Effects of solar radiation on dissolved ... M. Title Declining carrying capacity in the Bering Sea: Isotopic evidence from ...

59

Effect of radiation on transport in graphene  

Science Journals Connector (OSTI)

We study transport properties of graphene-based p-n junctions irradiated by electromagnetic field (EF). The resonant interaction of propagating quasiparticles with an external monochromatic radiation opens dynamical gaps in their spectrum, resulting in a strong modification of current-voltage characteristics of the junctions. The values of the gaps are proportional to the amplitude of EF. We find that the transmission of the quasiparticles in the junctions is determined by the tunneling through the gaps and can be fully suppressed when applying a sufficiently large radiation power. However, EF can not only suppress the current but also generate it. We demonstrate that if the height of the potential barrier exceeds a half of the photon energy, the directed current (photocurrent) flows through the junction without any dc bias voltage applied. Such a photocurrent arises as a result of inelastic quasiparticle tunneling assisted by one- or two-photon absorption. We calculate current-voltage characteristics of diverse graphene-based junctions and estimate their parameters necessary for the experimental observation of the photocurrent and transmission suppression.

S. V. Syzranov; M. V. Fistul; K. B. Efetov

2008-07-07T23:59:59.000Z

60

Effects of low levels of radiation on humans  

SciTech Connect

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

Auxier, J.A.

1981-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Third Radiation Effects Research Foundation Board of Councilors Meeting  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Third Radiation Effects Research Foundation Board of Councilors Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima July 22, 2013 - 4:54pm Addthis Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima The third Board of Councilors (BOC) meeting was held on June 18-19 at the Hiroshima Radiation Effects Research Foundation (RERF), a bi-national U.S.-Japan research organization. The BOC is the highest decision-making body at RERF, consisting of eight Councilors elected from the United States and Japan. A total of 23 participants, including 8 Councilors from the United States and Japan and officials from the U.S. and Japanese Governments, were present at the meeting. The Office of Health, Safety and

62

E-Print Network 3.0 - abscopal radiation effects Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

will introduce the theory of radiative transfer; the second part Summary: to greenhouse effect and solar radiation 6. Radiative heating and cooling a. The Chapman layer b....

63

Radiation Damage Effects in Candidate Titanates for Pu Disposition: Zirconolite  

SciTech Connect

This is the second of two papers on the results of radiation-induced damage accumulation in titanate ceramics that potentially could be used for weapons grade plutonium disposition. In the first paper we discussed the results from pyrochlore (betafite) based ceramics. In this paper, we discuss the effects of radiation-induced damage on the density and crystal structure of a nominally phase-pure zirconolite and two other zirconolite-bearing ceramics from the alpha decay of 238Pu. Macro (bulk) and micro (X-ray diffraction) swelling were found to be temperature independent, whereas the density determined with He gas pycnometry was temperature dependent. It took approximately 740 days (2.6?1018 ?/g) for the specimens to become X-ray amorphous—longer for the swelling to saturate. Unlike what we observed for the pyrochlore-based ceramics, we did not observe any phase changes associated with storage temperature and damage ingrowth. The forward dissolution rate at a pH value of 2 for material containing essentially all zirconolite is 1.7(4)?10-3 g/(m2?d). Very little pH dependence was observed for zirconolite specimens and, like we observed for the pyrochlore-bearing ceramics in this study, there was no dependence on the amount of radiation-induced damage. As with the pyrochlore, these materials did not become substantially friable with increasing radiation-induced damage. Even after the radiation-induced swelling saturated, the specimens remained physically intact with no evidence for microcracking. Thus, the material remains physically a viable material for the disposition of surplus weapons-grade Pu.

Strachan, Denis M.; Scheele, Randall D.; Buck, Edgar C.; Kozelisky, Anne E.; Sell, Rachel L.; Elovich, Robert J.; Buchmiller, William C.

2008-01-15T23:59:59.000Z

64

Errors and Uncertainties in Dose Reconstruction for Radiation Effects Research  

SciTech Connect

Dose reconstruction for studies of the health effects of ionizing radiation have been carried out for many decades. Major studies have included Japanese bomb survivors, atomic veterans, downwinders of the Nevada Test Site and Hanford, underground uranium miners, and populations of nuclear workers. For such studies to be credible, significant effort must be put into applying the best science to reconstructing unbiased absorbed doses to tissues and organs as a function of time. In many cases, more and more sophisticated dose reconstruction methods have been developed as studies progressed. For the example of the Japanese bomb survivors, the dose surrogate “distance from the hypocenter” was replaced by slant range, and then by TD65 doses, DS86 doses, and more recently DS02 doses. Over the years, it has become increasingly clear that an equal level of effort must be expended on the quantitative assessment of uncertainty in such doses, and to reducing and managing uncertainty. In this context, this paper reviews difficulties in terminology, explores the nature of Berkson and classical uncertainties in dose reconstruction through examples, and proposes a path forward for Joint Coordinating Committee for Radiation Effects Research (JCCRER) Project 2.4 that requires a reasonably small level of effort for DOSES-2008.

Strom, Daniel J.

2008-04-14T23:59:59.000Z

65

Advances in Radiation Mutagenesis through Studies on Drosophila  

DOE R&D Accomplishments (OSTI)

The approximately linear relation between radiation dose and induced lethals known for Drosophila spermatozoa, is now extended to spermatids. Data are included regarding oogonia. The linearity principle has been confined for minute structural changes in sperm as multi-hit events, on about the 1.5 power of the dose, long known for spermatozoa, is now extended to spermatids and late oocytes, for relatively short exposures. are found to allow union of broken chromosomes. Therefore, the frequencies are lower for more dispersed exposures of varies with lethals induced in late oocytes follow the same frequency pattern and there fore are multi-hit events. Yet han spermatozoan irradiation that two broken ends derived from nonreciprocal. The following is the order of decreasing radiation mutability of different stages found by ourselves and others: spermatids, spermatozoa in females, spermatozoa 0 to 1 day before ejaculation, earlier spermatozoa, late oocytes, gonia of either sex. Lethal frequencies for these stages range over approximately an order of magnitude, gross structural changes far more widely. Of potential usefulness is our extension of genesis by anoxia, known for spermatozoa in adult males, to those in pupal males and in females, to sperion is especially marked but the increase caused by substituting oxygen for air is less marked, perhaps because of enzymatic differences. In contrast, the induction of gross structural changes in oocytes, but not in spermatids, is markedly reduced by oxygen post-treatment; it is increased by dehydration. The efficacy of induction of structural changes by treatment of spermatozoa, whether with radiation or chemical mutagen, is correlated with the conditions of sperm utilization and egg production. Improving our perspective on radiation effects, some 800,000 offspring have been scored for spontaneous visible mutations of 13 specific loci. The average point-mutation rate was 0.5 to 1.0 per locus among 10/sup 5/ germ cells. Most mutation occurred in peri- fertilization stages. All loci studied mutated from one to nine times. Loci mutating oftener spontaneously also gave more radiation mutation, in other studies, Spectra of individual loci prove similar for spontaneous and induced mutation. Studies on back-mutation also showed similarity of spontaneous and radiation mutations. The doubling dose for back-mutations of forked induced in spermatozoa was several hundred roentgens, gonia at diverse loci. Recent analyses of human mutational load lead to mutation-rate estimated like those earlier based on extrapolations from Drosophila, thus supporting the significance for man of the present studies. (auth)

Muller, H. J.

1958-06-00T23:59:59.000Z

66

Experimental methodology for non-thermal effects of electromagnetic radiation on biologics  

E-Print Network (OSTI)

Appropriate equipment is needed for research on the effects of radio-frequency radiation from radio-frequency identification (RF-ID) systems on biological materials. In the present study, a complete test system comprising ...

Cox, Felicia C. A. I

2006-01-01T23:59:59.000Z

67

Radiation effects on polypropylene/polybutylene blends  

SciTech Connect

Polymer blends of polypropylene and polybutylene have been found to exhibit substantial maintenance of structural integrity after exposure to ionizing radiation. This radiation resistance has been found to be related to processing conditions and the resulting morphology of the blend. This article discusses (a) the processing conditions and the resulting mechanical properties after irradiation and (b) the role of morphology in this unexpected blend property.

Rolando, R.J. (3M Engineering Systems and Technology, St. Paul, MN (United States))

1993-06-01T23:59:59.000Z

68

Effects of gamma radiation on Serratia marcescens; a comparison of effects of two different exposure rates  

E-Print Network (OSTI)

'Donovan, Effect of gamma radiation on Serratia marcescens: Comparison of the radiosensi- tivity of pigmented and nonpigmented cells. Radiation Res, 48, 40-52 (1971). 18. Alison P. Casarett, Radiation ~Biolo . p. 159. Prentice-Hall, Inc. , Englewood Cliffs... EFFECTS OF GAMMA RADIATION ON SL'RNATIA MARCESCENS A COMPARISON OF EFFECTS OF TWO DIFFERENT EXPOSURE RATES A Thesis by CHRISTY ANNETTE MOORE Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirements...

Moore, Christy Annette

1972-01-01T23:59:59.000Z

69

Radiation effects in Si-Ge quantum size structure (Review)  

SciTech Connect

The article is dedicated to the review and analysis of the effects and processes occurring in Si-Ge quantum size semiconductor structures upon particle irradiation including ion implantation. Comparisons to bulk materials are drawn. The reasons of the enhanced radiation hardness of superlattices and quantum dots are elucidated. Some technological applications of the radiation treatment are reviewed.

Sobolev, N. A., E-mail: sobolev@ua.pt [Universidade de Aveiro, Departamento de Fisica and I3N (Portugal)

2013-02-15T23:59:59.000Z

70

Ionizing radiation effects on silicon test structures  

SciTech Connect

The effects of {sup 60}Co gamma irradiation on MOSCAPS and special junction diode detectors have been studied. The capacitors were used to ellicit the charge accumulation and anneal in two types of thermally grown oxides representative of those used in routine detector processing. Ion implanted, oxide passivated junction detectors having 0.25 and 1 cm{sup 2} areas and perimeter to area ratios of 1 (a square), 2 and 5 were designed and constructed to amplify the ionizing effects expected to largely affect junction edges through changes in fixed oxide charges. Detectors were exposed to over 4 Mrad and showed clear increases in leakage current in proportion to the junction edge length. Annealing schedules were determined to provide a continuous response to incremental irradiations and subsequent room temperature anneals of leakage current. Besides an increase in gate threshold, little effect on the C(V) response was found. PISCES simulation of the edge fields using different fixed oxide charge revealed regions of very high lateral fields near the junction edges for fixed charges in the 2 {times} 10{sup 12}/cm{sup 2} range expected from the capacitor studies which could be responsible for the observed leakage currents.

Kraner, H.W.; Beuttenmuller, R.; Chen, W.; Kierstead, J.A.; Li, Z.; Zhang, Y. [Brookhaven National Lab., Upton, NY (United States); Dou, L. [Wayne State Univ., Detroit, MI (United States); Fretwurst, E.; Lindstroem, G. [Univ. of Hamburg (Germany)

1993-12-01T23:59:59.000Z

71

Effects of Solar UV Radiation on Morphology and Photosynthesis of Filamentous Cyanobacterium Arthrospira platensis  

Science Journals Connector (OSTI)

...time of exposure to solar radiation (E and F). (A and...E and F) daily solar doses during the exposure period...Cyanobacteria growth & development radiation effects ultrastructure Dose-Response Relationship, Radiation Photosynthesis radiation...

Hongyan Wu; Kunshan Gao; Virginia E. Villafañe; Teruo Watanabe; E. Walter Helbling

2005-09-01T23:59:59.000Z

72

Radiation pressure on a moving body: beyond the Doppler effect  

Science Journals Connector (OSTI)

The dependence of macroscopic radiation pressure on the velocity of the object being pushed is commonly attributed to the Doppler effect. This need not be the case, and here we...

Horsley, S A R; Artoni, M; Rocca, G C La

2012-01-01T23:59:59.000Z

73

The effects of radiation on spermatogenesis in the albino rat as determined by semen analysis  

E-Print Network (OSTI)

rate all could be significant factors. Total body X-irradiation (470 r) in rats produced minimal alterations in the testes, namely depletion of spermatogonia (Gunn, et al. , 1960). 17 18 The effect of whole-body radiation on fertility of male rats...) Figure 22. Effect of Radiation on Weight Change (Chronic). no irradiation, demonstrated steady weekly increases through the investigation period. The average body weight of these animals at the initiation of this study was approximately 510 grams...

Lawson, Rommon Loy

1964-01-01T23:59:59.000Z

74

Effects of low-dose radiation on immune cell function using genetic and  

NLE Websites -- All DOE Office Websites (Extended Search)

low-dose radiation on immune cell function using genetic and low-dose radiation on immune cell function using genetic and metabolomics approaches Henghong Li Georgetown University Abstract The objectives of this study are to investigate acute and persistent effects of ionizing radiation and space radiation on immune cell subsets and function. The role(s) for p38 MAP kinase in such radiation responses is being investigated using a genetic approach where an engineered mouse line has had one wt p38α gene replaced with a dominantnegative mutant (p38α+/DN). T cells are one of the most radiosensitive cell types in vivo, and radiation is known to impact CD4 T cell function long term. T cells are normally activated by antigen, which triggers differentiation to specific subsets involving various cytokines. In addition, T cells have a

75

Incorporation of 3D Shortwave Radiative Effects within the Weather Research and Forecasting Model  

SciTech Connect

A principal goal of the Atmospheric Radiation Measurement (ARM) Program is to understand the 3D cloud-radiation problem from scales ranging from the local to the size of global climate model (GCM) grid squares. For climate models using typical cloud overlap schemes, 3D radiative effects are minimal for all but the most complicated cloud fields. However, with the introduction of ''superparameterization'' methods, where sub-grid cloud processes are accounted for by embedding high resolution 2D cloud system resolving models within a GCM grid cell, the impact of 3D radiative effects on the local scale becomes increasingly relevant (Randall et al. 2003). In a recent study, we examined this issue by comparing the heating rates produced from a 3D and 1D shortwave radiative transfer model for a variety of radar derived cloud fields (O'Hirok and Gautier 2005). As demonstrated in Figure 1, the heating rate differences for a large convective field can be significant where 3D effects produce areas o f intense local heating. This finding, however, does not address the more important question of whether 3D radiative effects can alter the dynamics and structure of a cloud field. To investigate that issue we have incorporated a 3D radiative transfer algorithm into the Weather Research and Forecasting (WRF) model. Here, we present very preliminary findings of a comparison between cloud fields generated from a high resolution non-hydrostatic mesoscale numerical weather model using 1D and 3D radiative transfer codes.

O'Hirok, W.; Ricchiazzi, P.; Gautier, C.

2005-03-18T23:59:59.000Z

76

Power line harmonic radiation: A systematic study using DEMETER spacecraft  

E-Print Network (OSTI)

Power line harmonic radiation: A systematic study using DEMETER spacecraft F. Nemec a,b,*, O of a systematic survey of Power line harmonic radiation (PLHR) observed by the DEMETER spacecraft. DEME- TER frequency spacing corresponds well to the power system frequency at anticipated source locations. Moreover

Santolik, Ondrej

77

Effects of Microwave Radiation on Oil Recovery  

Science Journals Connector (OSTI)

A variety of oil recovery methods have been developed and applied to mature and depleted reservoirs in order to improve the efficiency. Microwave radiation oil recovery method is a relatively new method and has been of great interest in the recent years. Crude oil is typically co?mingled with suspended solids and water. To increase oil recovery it is necessary to remove these components. The separation of oil from water and solids using gravitational settling methods is typically incomplete. Oil?in?water and oil?water?solid emulsions can be demulsified and separated into their individual layers by microwave radiation. The data also show that microwave separation is faster than gravity separation and can be faster than conventional heating at many conditions. After separation of emulsion into water and oil layers water can be discharged and oil is collected. High?frequency microwave recycling process can recover oil and gases from oil shale residual oil drill cuttings tar sands oil contaminated dredge/sediments tires and plastics with significantly greater yields and lower costs than are available utilizing existing known technologies. This process is environmentally friendly fuel?generating recycler to reduce waste cut emissions and save energy. This paper presents a critical review of Microwave radiation method for oil recovery.

2011-01-01T23:59:59.000Z

78

Doppler effect in the oscillator radiation process in the medium  

E-Print Network (OSTI)

The purpose of this paper is to investigate the radiation process of the charged particle passing through an external periodic field in a dispersive medium. In the optical range of spectrum we will consider two cases: first, the source has not eigenfrequency, and second, the source has eigenfrequency. In the first case, when the Cherenkov radiation occurs, the non-zero eigenfrequency produces a paradox for Doppler effect. It is shown that the absence of the eigenfrequency solves the paradox known in the literature. The question whether the process is normal (i.e. hard photons are being radiated under the small angles) or anomalous depends on the law of the medium dispersion. When the source has an eigenfrequency the Doppler effects can be either normal or anomalous. In the X-ray range of the oscillator radiation spectrum we have two photons radiated under the same angle- soft and hard. In this case the radiation obeys to so-called complicated Doppler effect, i.e. in the soft photon region we have anomalous Doppler effect and in the hard photon region we have normal Doppler effect.

Lekdar Gevorgian; Valeri Vardanyan

2011-02-25T23:59:59.000Z

79

RADIATION EFFECTS ON EPOXY/CARBON FIBER COMPOSITE  

SciTech Connect

The Department of Energy Savannah River Site vitrifies nuclear waste incident to defense programs through its Defense Waste Processing Facility (DWPF). The piping in the DWPF seal pot jumper configuration must withstand the stresses during an unlikely but potential deflagration event, and maintain its safety function for a 20-year service life. Carbon fiber-reinforced epoxy composites (CFR) were proposed for protection and reinforcement of piping during such an event. The proposed CFR materials have been ASME-approved (Section XI, Code Case N-589-1) for post-construction maintenance and is DOT-compliant per 49CFR 192 and 195. The proposed carbon fiber/epoxy composite reinforcement system was originally developed for pipeline rehabilitation and post-construction maintenance in petrochemical, refineries, DOT applications and other industries. The effects of ionizing radiation on polymers and organic materials have been studied for many years. The majority of available data are based on traditional exposures to gamma irradiation at high dose rates ({approx}10,000 Gy/hr) allowing high total dose within reasonable test periods and general comparison of different materials exposed at such conditions. However, studies in recent years have shown that degradation of many polymers are sensitive to dose rate, with more severe degradation often observed at similar or even lower total doses when exposed to lower dose rates. This behavior has been primarily attributed to diffusion-limited oxidation which is minimized during very high dose rate exposures. Most test standards for accelerated aging and nuclear qualification of components acknowledge these limitations. The results of testing to determine the radiation resistance and microstructural effects of gamma irradiation exposure on a bisphenol-A based epoxy matrix composite reinforced with carbon fibers are presented. This work provides a foundation for a more extensive evaluation of dose rate effects on advanced epoxy reinforced composites.

Hoffman, E; Eric Skidmore, E

2008-12-12T23:59:59.000Z

80

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Abstract Abstract Title: Effects of Low Doses of Radiation on DNA Repair (PNNL Project # 42699) Authors: Eric J. Ackerman, Ph.D. Institutions: Pacific Northwest National Laboratory Richland, WA We developed a functional assay to measure the effects of LDR on repair of many different lesions representative of those found in cells as consequences of normal oxidative metabolism, as well as those caused by radiation. Currently only 1/10th attomole =105 damaged molecules/cell and 3000 cells/measurement are required. We have found that even low doses (10 rad) exert measurable effects on DNA repair. Interestingly, the amount of DNA repair increases at 10-50 rads, plateaus, and then increases even further at higher doses well below doses where radiation-induced lethality

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Transgenerational Effects of Radiation and Chemicals in Mice and Humans  

Science Journals Connector (OSTI)

......transgenerational radiation car- cinogenesis. In other words...caused functional damage and defective gonad development.6,1214...studies on transgenerational car- cinogenesis were started from...leukemia in their offspring. Car- cinogenesis 19: 15531558......

Taisei Nomura

2006-01-01T23:59:59.000Z

82

Radiation effects on reactor pressure vessel supports  

SciTech Connect

The purpose of this report is to present the findings from the work done in accordance with the Task Action Plan developed to resolve the Nuclear Regulatory Commission (NRC) Generic Safety Issue No. 15, (GSI-15). GSI-15 was established to evaluate the potential for low-temperature, low-flux-level neutron irradiation to embrittle reactor pressure vessel (RPV) supports to the point of compromising plant safety. An evaluation of surveillance samples from the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory (ORNL) had suggested that some materials used for RPV supports in pressurized-water reactors could exhibit higher than expected embrittlement rates. However, further tests designed to evaluate the applicability of the HFIR data to reactor RPV supports under operating conditions led to the conclusion that RPV supports could be evaluated using traditional method. It was found that the unique HFIR radiation environment allowed the gamma radiation to contribute significantly to the embrittlement. The shielding provided by the thick steel RPV shell ensures that degradation of RPV supports from gamma irradiation is improbable or minimal. The findings reported herein were used, in part, as the basis for technical resolution of the issue.

Johnson, R.E. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Engineering Technology; Lipinski, R.E. [Idaho National Engineering Lab., Rockville, MD (United States)

1996-05-01T23:59:59.000Z

83

The Effect of Non-Lambertian Surface Reflectance on Aerosol Radiative Forcing  

SciTech Connect

Surface reflectance is an important factor in determining the strength of aerosol radiative forcing. Previous studies of radiative forcing assumed that the reflected surface radiance is isotropic and does not depend on incident illumination angle. This Lambertian reflection model is not a very good descriptor of reflectance from real land and ocean surfaces. In this study we present computational results for the seasonal average of short and long wave aerosol radiative forcing at the top of the atmosphere and at the surface. The effect of the Lambertian assumption is found through comparison with calculations using a more detailed bi-direction reflectance distribution function (BRDF).

Ricchiazzi, P.; O'Hirok, W.; Gautier, C.

2005-03-18T23:59:59.000Z

84

Low Dose Radiation Exposure: Exploring Bystander Effects In Vivo.  

NLE Websites -- All DOE Office Websites (Extended Search)

Exposure: Exploring Bystander Effects Exposure: Exploring Bystander Effects In Vivo. 1 Blyth, B.J., 1 Sykes, P.J. 1 Department of Haematology and Genetic Pathology, Flinders University and Medical Centre, Bedford Park, South Australia, 5042, The general population is daily exposed to chronic, low doses of ionizing radiation from both natural and artificial sources. The shape of the radiation dose-response curve at these low doses is currently linearly extrapolated from data obtained after high dose exposure due to the low sensitivity of traditional biological assays after near-background exposures. At odds with this Linear No-Threshold model, are the phenomena collectively referred to as the radiation-induced bystander effect. The bystander effect describes a collection of in vitro

85

Radiation Damange Effects in Candidate Titanates for Plutonium Disposition: Pyrochlore.  

SciTech Connect

Laboratory experiments were conducted to verify certain assumptions as to the swelling, chemical durability, and microcracking that might occur in a waste-form ceramic as 239Pu decays. To study to effects of 239Pu decay, 238Pu, a short-lived isotope, was incorporated into a pyrochlore-rich baseline titanate – one that is formulated for pyrochlore as the dominant phase. The self-irradiation with 238Pu provided information on damage to the crystal structures of the phases in the ceramic as well as changes in dimensions, densities, and chemical durability. Overall, the pyrochlore baseline material appears to be a viable material for the immobilization of weapons-ready Pu. The physical and chemical properties of this material are not adversely affected by the material becoming amorphous from radiation-induced damage.

Strachan, Denis M.; Scheele, Randall D.; Buck, Edgar C.; Kozelisky, Anne E.; Sell, Rachel L.; Elovich, Robert J.; Buchmiller, William C.

2005-10-15T23:59:59.000Z

86

Compensating effect of the coherent synchrotron radiation in bunch compressors  

Typical bunch compression for a high-gain free-electron laser (FEL) requires a large compression ratio. Frequently, this compression is distributed in multiple stages along the beam transport line. However, for a high-gain FEL driven by an energy recovery linac (ERL), compression must be accomplished in a single strong compressor located at the beam line’s end; otherwise the electron beam would be affected severely by coherent synchrotron radiation (CSR) in the ERL’s arcs. In such a scheme, the CSR originating from the strong compressors could greatly degrade the quality of the electron beam. In this paper, we present our design for a bunch compressor that will limit the effect of CSR on the e-beam’s quality. We discuss our findings from a study of such a compressor, and detail its potential for an FEL driven by a multipass ERL developed for the electron-Relativistic Heavy Ion Collider.

Jing, Yichao; Hao, Yue; Litvinenko, Vladimir N.

2013-06-01T23:59:59.000Z

87

RADIATION EFFECTS ON EPOXY CARBON FIBER COMPOSITE  

SciTech Connect

Carbon fiber-reinforced bisphenol-A epoxy matrix composite was evaluated for gamma radiation resistance. The composite was exposed to total gamma doses of 50, 100, and 200 Mrad. Irradiated and baseline samples were tested for tensile strength, hardness and evaluated using FTIR (Fourier transform infrared) spectroscopy and DSC (differential scanning calorimetry) for structural changes. Scanning electron microscopy was used to evaluate microstructural behavior. Mechanical testing of the composite bars revealed no apparent change in modulus, strain to failure, or fracture strength after exposures. However, testing of only the epoxy matrix revealed changes in hardness, thermal properties, and FTIR results with increasing gamma irradiation. The results suggest the epoxy within the composite can be affected by exposure to gamma irradiation.

Hoffman, E

2008-05-30T23:59:59.000Z

88

The Effects of Radiation on Development of Prostate Cancer and Prostatic  

NLE Websites -- All DOE Office Websites (Extended Search)

Effects of Radiation on Development of Prostate Cancer and Prostatic Effects of Radiation on Development of Prostate Cancer and Prostatic Hyperplasia in Canine Model Gayle Woloschak Northwestern University Abstract Purpose/Objective(s): There have been few studies analyzing radiation-induced prostate cancer in humans or animals. Our research attempts to fill this void by determining the effects of cobalt-60 gamma radiation on the incidence of prostate cancer and prostatic hyperplasia in a large cohort of beagle dogs. Material/Methods: The subjects for the experiment were beagle dogs, which were chosen due to physiologic and anatomic similarities to humans (Thompson, 1989). We retrospectively analyzed data from historic irradiation experiments conducted at Argonne National Laboratory on 347 beagles. The cobalt-60 cohort consisted of 268 dogs, which received whole

89

Radiation worker health study: Scoping phase: Final report  

SciTech Connect

The purpose of this project was to develop a scope of work for an epidemiologic study of the health of workers at nuclear utilities. We propose a study of cancer mortality among electric utility personnel assigned to nuclear generating stations. The primary goal of the study is to provide information to assist in maintaining a healthy work environment in electric utilities; such information would also help to resolve some uncertainties about the effects of low-level ionizing radiation by providing direct observation of human beings exposed at low doses and dose rates. Workers at each nuclear generating station would be identified from company records, their dose histories would be collected, and their vital status would be ascertained as well as cause of death, if deceased. This study would be historical in that past records would be used and prospective in that employees would continue to be followed in future years. Our estimates indicate that a study population composed of employees and contractors at all commercial nuclear generating stations would total approximately 2,000,000 person-years of observation and would be adequate to detect (or exclude) a 50 percent increase in leukemia with reasonable statistical power. 44 refs., 4 figs., 3 tabs.

Dreyer, N.A.; Wilkinson, G.S.; Loughlin, J.E.

1988-11-01T23:59:59.000Z

90

Environmental Radiation Effects: A Need to Question Old Paradigms  

SciTech Connect

A historical perspective is given of the current paradigm that does not explicitly protect the environment from radiation, but instead, relies on the concept that if dose limits are set to protect humans then the environment is automatically protected as well. We summarize recent international questioning of this paradigm and briefly present three different frameworks for protecting biota that are being considered by the U.S. DOE, the Canadian government and the International Commission on Radiological Protection. We emphasize that an enhanced collaboration is required between what has traditionally been separated disciplines of radiation biology and radiation ecology if we are going to properly address the current environmental radiation problems. We then summarize results generated from an EMSP grant that allowed us to develop a Low Dose Irradiation Facility that specifically addresses effects of low-level, chronic irradiation on multiple levels of biological organization.

Hinton, T.G.; Bedford, J.; Ulsh, B.; Whicker, F. Ward

2003-03-27T23:59:59.000Z

91

Geometric Doppler Effect: Spin-Split Dispersion of Thermal Radiation  

Science Journals Connector (OSTI)

A geometric Doppler effect manifested by a spin-split dispersion relation of thermal radiation is observed. A spin-dependent dispersion splitting was obtained in a structure consisting of a coupled thermal antenna array. The effect is due to a spin-orbit interaction resulting from the dynamics of the surface waves propagating along the structure whose local anisotropy axis is rotated in space. The observation of the spin-symmetry breaking in thermal radiation may be utilized for manipulation of spontaneous or stimulated emission.

Nir Dahan; Yuri Gorodetski; Kobi Frischwasser; Vladimir Kleiner; Erez Hasman

2010-09-21T23:59:59.000Z

92

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Doses of Radiation on DNA Repair Low Doses of Radiation on DNA Repair Eric Ackerman Pacific Northwest National Laboratory Why this Project? Even low doses (0.1 Gy) exert measurable effects on DNA repair. The first-known oxidative lesion repaired only by nucleotide excision repair found in normal cells is cyclo-dA. This lesion is found in normal cells and thought to be a byproduct of oxidative metabolism. When this lesion occurs, it stimulates repair. If repair is stimulated by low dose radiation, there are some implications for human health. For example, do some individuals exhibit a greater, lower, or no stimulation to certain DNA lesions? If there are population polymorphism that influence DNA repair, then it would be possible to use our assay for screening individuals for repair sensitivity.

93

A STATIONARY STATE APPROACH TO RADIATIONLESS TRANSITIONS: RADIATION BANDWIDTH EFFECT ON EXCITATION PROCESSES IN POLYATOMIC MOLECULES  

Science Journals Connector (OSTI)

...bandwidth of the incident radiation. The conditions of...sufficiently narrow radiation bandwidths, it is demonstrated...should be regarded as occuring to molecular stationary...RADIATIONLESS TRANSITIONS: RADIATION BANDWIDTH EFFECT ON...usual approach, are naturally taken into account...

William Rhodes; Bryan R. Henry; Michael Kasha

1969-01-01T23:59:59.000Z

94

Inactivation of aflatoxin B1 by using the synergistic effect of hydrogen peroxide and gamma radiation.  

Science Journals Connector (OSTI)

...peroxide. A 100-krad dose of gamma radiation was sufficient to inactivate...peroxide. A 100-krad dose of gamma radiation was sufficient to inactivate...inhibitors pharmacology radiation effects Animals Dose-Response Relationship...

U D Patel; P Govindarajan; P J Dave

1989-02-01T23:59:59.000Z

95

Center for Environmental Radiation Studies 1 Texas Tech University  

E-Print Network (OSTI)

and international nuclear safety. Critical Success Factors Critical measures of success shall include regarding nuclear research, nuclear safety, biological effects, and homeland security · Training of graduate students and post-doctorates in the areas of molecular genetic responses, radiation dosimetry

Chesser, Ronald Keith

96

Effect of surface treatments on radiation buildup in steam generators  

SciTech Connect

A study of the effect of surface preparation on the radiation buildup of steam generator materials of construction was conducted. The tests consisted of exposing treated manway seal plates to primary reactor coolant during the second through the fifth fuel cycle of the Chinon B1 pressurized water reactor. The pretreatments included: mechanical polishing, electropolishing (either on the as received surface or on a surface which had been previously mechanically polished), and passivation via the RCT (laboratory) process or the Framatome (in situ) process. Radioactivity buildup was determined at the end of each fuel cycle. A selected number of the seal plates were removed from the steam generators after each exposure cycle for destructive examinations. The electropolished surfaces exhibited a significantly lower radioactive buildup rate; an average factor of five less buildup compared to an as-received surface. Passivation of the electropolished surface, especially via the RCT process, reduced the buildup rate still further by a factor of two over the electropolished-only surface. Examination of the surfaces by profilometry, scanning electron microscopy, etc., after exposure indicated no detrimental effects on the surface characteristics attributable to the surface treatments. A program has now been instituted to electropolish the steam generator channel heads of all new reactors in France, as well as the steam generators intended for replacement in existing plants. 1 ref., 5 figs., 10 tabs.

Not Available

1991-11-01T23:59:59.000Z

97

Low Dose Radiation Research Program: Characterizing Bystander Effects  

NLE Websites -- All DOE Office Websites (Extended Search)

Irradiation. Irradiation. Authors: L.A. Braby and J.R. Ford. Institutions: Texas A&M University. Bystander effects, which are typically seen as in increase in the cellular concentration of specific repair related molecules or as cytogenetic changes which appear to be the consequence of DNA damage, may be a significant factor in the risk of long-term health effects of low doses of radiation. These effects clearly increase the effective size of the target for radiation response, from the diameter of a single cell or cell nucleus to something significantly larger, by bringing additional cells into the process. It is unclear whether this larger target will result in an increase or a decrease in the probability of inducing a change which would be detrimental to the health of the organism, but it clearly reduces the

98

Radiative Neutron Capture on Carbon-14 in Effective Field Theory  

E-Print Network (OSTI)

The cross section for radiative capture of neutron on carbon-14 is calculated using the model-independent formalism of halo effective field theory. The dominant contribution from E1 transition is considered, and the cross section is expressed in terms of elastic scattering parameters of the effective range expansion. Contributions from both resonant and non-resonant interaction are calculated. Significant interference between these leads to a capture contribution that deviates from simple Breit-Wigner resonance form.

Gautam Rupak; Lakma Fernando; Akshay Vaghani

2012-04-19T23:59:59.000Z

99

Radiative Neutron Capture on Carbon-14 in Effective Field Theory  

E-Print Network (OSTI)

The cross section for radiative capture of neutron on carbon-14 is calculated using the model-independent formalism of halo effective field theory. The dominant contribution from E1 transition is considered, and the cross section is expressed in terms of elastic scattering parameters of the effective range expansion. Contributions from both resonant and non-resonant interaction are calculated. Significant interference between these leads to a capture contribution that deviates from simple Breit-Wigner resonance form.

Rupak, Gautam; Vaghani, Akshay

2012-01-01T23:59:59.000Z

100

Radiation dose measurement in gastrointestinal studies  

Science Journals Connector (OSTI)

......Technology, PO Box 1908, Khartoum, Sudan 2 Medical Physics Department...has been limited up to now in Sudan. DRL for barium studies have...All the TLD chips had the same thermal history. The calibration cycle...quality control tests performed by Sudan Atomic Energy Commission. Investigation......

A. Sulieman; M. Elzaki; C. Kappas; K. Theodorou

2011-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Preliminary Studies on the Variational Assimilation of Cloud-Radiation Observations Using ARM Observations  

NLE Websites -- All DOE Office Websites (Extended Search)

Studies on the Variational Assimilation Studies on the Variational Assimilation of Cloud-Radiation Observations Using ARM Observations M. Janisková, J.-F. Mahfouf, and J.-J. Morcrette European Centre for Medium-Range Weather Forecasts Shinfield Park, Reading Berskshire, United Kingdom Abstract A linearized cloud scheme and a radiation scheme including cloud effects have been developed at European Centre for Medium-Range Weather Forecasts (ECMWF) to assimilate cloud properties in the framework of the four-dimensional variational (4D-Var) assimilation system. To investigate the potential of those schemes to modify the model temperature, humidity and cloud profiles and produce a better match to the observed radiation fluxes, one-dimensional variational (1D-Var) assimilation experiments have been carried out using data from the Atmospheric Radiation Measurement (ARM)

102

American Society for Radiation Oncology (ASTRO) 2012 Workforce Study: The Radiation Oncologists' and Residents' Perspectives  

SciTech Connect

Purpose: The American Society for Radiation Oncology (ASTRO) conducted the 2012 Radiation Oncology Workforce Survey to obtain an up-to-date picture of the workforce, assess its needs and concerns, and identify quality and safety improvement opportunities. The results pertaining to radiation oncologists (ROs) and residents (RORs) are presented here. Methods: The ASTRO Workforce Subcommittee, in collaboration with allied radiation oncology professional societies, conducted a survey study in early 2012. An online survey questionnaire was sent to all segments of the radiation oncology workforce. Respondents who were actively working were included in the analysis. This manuscript describes the data for ROs and RORs. Results: A total of 3618 ROs and 568 RORs were surveyed. The response rate for both groups was 29%, with 1047 RO and 165 ROR responses. Among ROs, the 2 most common racial groups were white (80%) and Asian (15%), and the male-to-female ratio was 2.85 (74% male). The median age of ROs was 51. ROs averaged 253.4 new patient consults in a year and 22.9 on-treatment patients. More than 86% of ROs reported being satisfied or very satisfied overall with their career. Close to half of ROs reported having burnout feelings. There was a trend toward more frequent burnout feelings with increasing numbers of new patient consults. ROs' top concerns were related to documentation, reimbursement, and patients' health insurance coverage. Ninety-five percent of ROs felt confident when implementing new technology. Fifty-one percent of ROs thought that the supply of ROs was balanced with demand, and 33% perceived an oversupply. Conclusions: This study provides a current snapshot of the 2012 radiation oncology physician workforce. There was a predominance of whites and men. Job satisfaction level was high. However a substantial fraction of ROs reported burnout feelings. Perceptions about supply and demand balance were mixed. ROs top concerns reflect areas of attention for the healthcare sector as a whole.

Pohar, Surjeet, E-mail: spohar@iuhealth.org [Indiana University Health East, Indianapolis, Indiana (United States); Fung, Claire Y. [Commonwealth Newburyport Cancer Center, Newburyport, Massachusetts (United States); Hopkins, Shane [William R. Bliss Cancer Center, Ames, Iowa (United States); Miller, Robert [Mayo Clinic, Rochester, Minnesota (United States); Azawi, Samar [VA Veteran Hospital/University of California Irvine, Newport Beach, California (United States); Arnone, Anna; Patton, Caroline [ASTRO, Fairfax, Virginia (United States); Olsen, Christine [Massachusetts General Hospital, Boston, Massachusetts (United States)

2013-12-01T23:59:59.000Z

103

Consideration of Dynamical Effects on Parameterization of Clooud radiative Properties  

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Consideration of Dynamical Effects on Consideration of Dynamical Effects on Parameterization of Cloud Radiative Properties P. H. Daum and Y. Liu Environmental Sciences Department Brookhaven National Laboratory Upton, New York Introduction Effective radius (r e ) (defined as the ratio of the third to the second moment of a droplet size distribution) is one of the key variables that are used for calculation of the radiative properties of liquid water clouds (Hansen and Travis 1974). The inclusion and parameterization of r e in climate models has proven to be critical for assessing global climate change (Slingo 1990, Dandin et al. 1997). It has been demonstrated empirically (Pontikis and Hicks 1992, Bower and Choularton 1992, Bower et al. 1994, Martin et al. 1994, Liu and Hallett 1997, Reid et al. 1998, Liu and Daum 2000a), as well theoretically (Liu and

104

Technical Sessions A Study of Longwave Radiation Codes for Climate Studies:  

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A Study of Longwave Radiation A Study of Longwave Radiation Codes for Climate Studies: Validation with ARM Observations and Tests in General Circulation Models R. G. Ellingson F. Baer Department of Meteorology University of Maryland College Park, MD 20742 Introduction the radiation sensitivity problem. We anticipate that the outcome of this approach will provide both a better longwave radiative forcing algorithm and a better understanding of how longwave radiative forcing influences the equilibrium climate of the atmosphere. Nature of Longwave Problems Longwave radiation quantities-radiances, fluxes and heating rates-are usually calculated in GCM models as the cloud amount weighted average of the values for clear and homogeneous cloud conditions. For example, the downward flux at the surface, F, may be written as

105

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland  

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non-targeted effects of low dose ionizing radiation on the mammary gland non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains that differ in susceptibility to tumorigenesis Joni D. Mott, Antoine M. Snijders, Alvin Lo, Dinah Levy-Groesser, Bahram Parvin, Andrew J. Wyrobek, Jian-Hua Mao, and Mina J. Bissell Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley CA 94720 Goal: Within the Lawrence Berkeley National Laboratory's SFA, Project 2, our studies focus on utilizing three dimensional (3D) cell culture models as surrogates for in vivo studies to determine how low doses of ionizing radiation influence mammary gland tissue architecture and how this may relate both to tumor progression and/or adaptive response.

106

Experimental studies of radiation damage of silicon detectors. Internal report  

SciTech Connect

New particle physics experiments are correlated with high luminosity and/or high energy. The new generation of colliding beam machines which will be constructed will make an extrapolation of a factor of 100 in the center of mass energy and of 1000 in luminosity beyond present accelerators. The scientific community hopes that very exciting physics results could be achieved this way, from the solution to the problem of electroweak symmetry breaking to the possible discovery of new, unpredicted phenomena. The particles which compose the radiation field are: electrons, pions, neutrons, protons and photons. It has become evident that the problem of the radiation resistance of detectors in this severe environment is a crucial one. This situation is complicated more by the fact that detectors must work all the run time of the machine, and better all the time of the experiment, without replacement (part or whole). So, studies related to the investigation of the radiation hardness of all detector parts, are developing. The studies are in part material and device characterization after irradiation, and in part technological developments, made in order to find harder, cheaper technologies, for larger surfaces. Semiconductor detectors have proven to be a good choice for vertex and calorimeter. Both fixed target machines and colliders had utilized in the past silicon junction detectors as the whole or part of the detection system. Precision beam hodoscopes and sophisticated trigger devices with silicon are equally used. The associated electronics in located near the detectors, and is subjected to the same radiation fields. Studies of material and device radiation hardness are developing in parallel. Here the authors present results on the radiation hardness of silicon, both as a bulk material and as detectors, to neutron irradiation at high fluences.

Angelescu, T.; Ghete, V.M.; Ghiordanescu, N.; Lazanu, I.; Mihul, A. [Univ. of Bucharest (Romania); Golutvin, I.; Lazanu, S.; Savin, I.; Vasilescu, A. [JINR, Dubna (Russian Federation); Biggeri, U.; Borchi, E.; Bruzzi, M. [Univ. of Florence (Italy)]|[INFN, Florence (Italy); Li, Z.; Kraner, H.W. [Brookhaven National Lab., Upton, NY (United States)

1994-02-01T23:59:59.000Z

107

A fourier spectrometer for studying the radiation from Josephson Junctions  

SciTech Connect

The paper describes a Fourier spectrometer designed to study the radiation generated by a Josephson junction in the millimeter and FIR bands with a resolution of {approx}2 GHz in the two-pass mode and {approx}1 GHz in the multipass mode. A feature is that one Josephson junctions operates as both generator and detector at the same time.

Verevkin, A.A.; Il`in, V.A.; Lipatov, A.P. [V.I. Lenin Moscow Pedagogical State Univ., Moscow (Russian Federation)

1995-06-01T23:59:59.000Z

108

Use of In Situ Observations to Characterize Cloud Microphysical and Radiative Properties: Application to Climate Studies  

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Use of In Situ Observations to Characterize Use of In Situ Observations to Characterize Cloud Microphysical and Radiative Properties: Application to Climate Studies G. M. McFarquhar and T. Nousiainen Department of Atmospheric Sciences University of Illinois Urbana, Illinois M. S. Timlin, S. F. Iacobellis, and R. C. J. Somerville Scripps Institution of Oceanography La Jolla, California Introduction Cloud radiative feedback is the most important effect determining climate response to human activity. Ice clouds reflect solar radiation and absorb thermal emission from the ground and the lower atmosphere and emit infrared radiation to space. The representation of these processes in models affects future climate predictions and there is much uncertainty in the representation of these processes. The size and

109

Radiation Damage Effects in Candidate Titanates for Pu Disposition: Pyrochlore  

SciTech Connect

Laboratory experiments on titanate ceramics were performed to verify whether certain assumptions are valid regarding the swelling, chemical durability, and microcracking that might occur as 239Pu decays. Titanate ceramics are the material of choice for the immobilization of surplus weapons-grade Pu. The short-lived isotope, 238Pu, was incorporated into the ceramic formulation to accelerate the effects of radiation induced damage. We report on the effects of this damage on the density (volumetric swelling <6%), crystal structure of pyrochlore-bearing specimens (amorphous after about 2?1018 ?/g), and dissolution (no change from fully the crystalline specimen). Even though the specimens became amorphous during the tests, there was no evidence for microcracking in the photomicrographs from the scanning electron microscope. Thus, although pyrochlore is susceptible to radiation-induced damage, the material remains chemically and physically viable as a material for immobilizing surplus weapons-grade Pu.

Strachan, Denis M.; Scheele, Randall D.; Buck, Edgar C.; Icenhower, Jonathan P.; Kozelisky, Anne E.; Sell, Rachel L.; Elovich, Robert J.; Buchmiller, William C.

2005-10-15T23:59:59.000Z

110

Radiation Damage Effects in Candidate Titanates for Pu Disposition: Zirconolite  

SciTech Connect

Specimens of titanate ceramics containing approximately 10 mass% 238Pu were tested to determine the long-term effects of radiation-induced damage from the ? decay of 239Pu that would have been disposed of in the nuclear-waste repository at Yucca Mountain. These tests provided information on the changes in bulk properties such as dimensions, densities, and chemical durability. Although these materials become amorphous at low doses, the specimens remained physically strong. Even after the radiation-induced swelling saturated, the specimens remained physically intact with no evidence for microcracking. Thus, in combination with results reported previously on similar materials, the material remains a physically viable material for the disposition of surplus weapons-grade Pu.

Strachan, Denis M.; Scheele, Randall D.; Buck, Edgar C.; Kozelisky, Anne E.; Sell, Rachel L.; Elovich, Robert J.; Buchmiller, William C.

2008-01-15T23:59:59.000Z

111

Radiation from a moving planar dipole layer: patch potentials vs dynamical Casimir effect  

E-Print Network (OSTI)

We study the classical electromagnetic radiation due to the presence of a dipole layer on a plane that performs a bounded motion along its normal direction, to the first non-trivial order in the amplitude of that motion. We show that the total emitted power may be written in terms of the dipole layer autocorrelation function. We then apply the general expression for the emitted power to cases where the dipole layer models the presence of patch potentials, comparing the magnitude of the emitted radiation with that coming from the quantum vacuum in the presence of a moving perfect conductor (dynamical Casimir effect).

Cesar D. Fosco; Francisco D. Mazzitelli

2014-03-08T23:59:59.000Z

112

Estimating Radiation Risk from Total Effective Dose Equivalent...  

National Nuclear Security Administration (NNSA)

and UNSCEAR 1988 in Radiation Risk Assessment - Lifetime Total Cancer Mortality Risk Estimates at Low Doses and Low Dose Rates for Low-LET Radiation, Committee on Interagency...

113

Radiation effects on a zeolite ion exchanger and a pollucite  

SciTech Connect

Cation exchange capacity and selective Cs and Sr ion sorption measurements were found to be too insensitive to detect radiation effects on irradiated Ionsiv-IE-95 zeolite. However, leaching the zeolite while under ..gamma..-irradiation caused a modest increase in the desorption of exchangeable ions. Gamma-irradiation and subsequent leaching of a natural pollucite also slightly enhanced the leachability of this material. The increased desorption of ions from the zeolite and the enhanced leachability of the pollucite are apparently caused by a decrease in pH due to the generation of acidic species during irradiation.

Komarneni, S.; Palau, G.L.; Pillay, K.K.S.

1983-01-01T23:59:59.000Z

114

A Study of Radiative Bottomonium Transitions using Converted Photons  

SciTech Connect

The authors use (111 {+-} 1) million {Upsilon}(3S) and (89 {+-} 1) million {Upsilon}(2S) events recorded by the BABAR detector at the PEP-II B-factory at SLAC to perform a study of radiative transitions betwen bottomonium states using photons that have been converted to e{sup +}e{sup -} pairs by the detector material. They observe {Upsilon}(3S) {yields} {gamma}{chi}{sub b0,2}(1P) decay, make precise measurements of the branching fractions for {chi}{sub b1,2}(1P, 2P) {yields} {gamma}{Upsilon}(1S) and {chi}{sub b1,2}(2P) {yields} {gamma}{Upsilon}(2S) decays, and search for radiative decay to the {eta}{sub b}(1S) and {eta}{sub b}(2S) states.

Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; /INFN, Bari /Bari U.; Milanes, D.A.; /INFN, Bari; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; /UC, Berkeley; Koch, H.; Schroeder, T.; /Ruhr U., Bochum; Asgeirsson, D.J.; Hearty, C.; /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Paris U., VI-VII /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

2011-08-15T23:59:59.000Z

115

Parallelization of Radiation Therapy Treatment Planning(RTTP) : A Case Study \\Lambda  

E-Print Network (OSTI)

Abstract Radiation therapy uses ionizing radiation to treat cancer­ ous tumors. This paper reports our, thereby concentrating radiation dose in the tumor. The maximum dose that can be delivered to the tumorParallelization of Radiation Therapy Treatment Planning(RTTP) : A Case Study \\Lambda V. Chaudhary

Xu, Cheng-Zhong

116

Multi-Dimensional Effects in Longwave Radiative Forcing of PBL Clouds  

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Multi-Dimensional Effects in Longwave Radiative Forcing of PBL Clouds D. B. Mechem and Y. L. Kogan Cooperative Institute for Mesoscale Meteorological Studies University of Oklahoma Norman, Oklahoma M. Ovtchinnikov Pacific Northwest National Laboratory Richland, Washington K. F. Evans University of Colorado Boulder, Colorado A. B. Davis Los Alamos National Laboratory Los Alamos, New Mexico R. F. Cahalan National Aeronautic and Space Administration Goddard Space Flight Center Greenbelt, Maryland E. E. Takara and R. G. Ellingson Florida State University Tallahassee, Florida 1. Introduction Numerical cloud models nearly universally employ one-dimensional (1D) treatments of radiative transfer (RT). Radiative transfer is typically implemented as a 2- or 4-stream approximation to the

117

Posters Treatment of Cloud Radiative Effects in General Circulation...  

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optical properties and 2) to study the effects of cloudradiation- climate interaction on climate simulations. This report summarizes project progress from March 1993 to March...

118

Radiation Effects in the Chernobyl and Kyshtym Aquatic Ecosystems  

Science Journals Connector (OSTI)

This paper evaluates studies on the effects of radioactive pollution on hydrobionts in natural conditions as published in the former USSR and the CIS.

G. G. Polikarpov; V. G. Tsytsugina

1996-01-01T23:59:59.000Z

119

Radiation damage effects in candidate titanates for Pu disposition: Zirconolite  

Science Journals Connector (OSTI)

Results from studies of radiation-induced damage from the alpha decay of 238Pu on the density and crystal structure of a nominally phase-pure zirconolite and two other zirconolite-bearing ceramics are discussed. Macro and micro swelling were found to be temperature independent, whereas the density determined with He gas pycnometry was temperature dependent. Approximately 2.6 × 1018 ?/g were needed to render the specimens X-ray amorphous– more to saturate the swelling. Unlike pyrochlore-based ceramics, we did not observe any phase changes associated with storage temperature and damage ingrowth. The forward dissolution rate at a pH value of 2 for material containing essentially all zirconolite is 1.7(4) × 10?3 g/(m2 d) with very little pH dependence and no dependence on the amount of radiation-induced damage. Even after the radiation-induced swelling saturated, the specimens remained physically intact with no evidence for microcracking. Thus, the material remains physically a viable material for the disposition of surplus weapons-grade Pu.

D.M. Strachan; R.D. Scheele; E.C. Buck; A.E. Kozelisky; R.L. Sell; R.J. Elovich; W.C. Buchmiller

2008-01-01T23:59:59.000Z

120

UNSCEAR Report 2000: Sources and Effects of Ionizing Radiation  

Science Journals Connector (OSTI)

Since its inception in 1955 the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has periodically undertaken a broad review of the sources and the effects of ionising radiation. This latest report is in two concurrently published separate volumes. Volumes I and II provide updated reviews of sources and effects of ionising radiation respectively. A considerable amount of new material supports the review of sources. The review of biological effects takes on board various contemporary issues raised by the `linear-no-threshold' controversy. Particular emphasis has been given to the evaluation of exposures and health consequences of the Chernobyl accident. As usual the report has an extended summary (17 pages) backed up by a number of technical annexes (A-J). The annexes have a wealth of basic data, extensive tables and voluminous reference lists. The two volumes are available separately from the United Nations and cost £60 per volume. They are also available from the Stationery Office, but only as a two volume set. If you are interested only in `sources' then you should be aware that the source-related aspects of the Chernobyl accident are largely covered in volume II on effects. Annex A of volume I provides a description of the methodologies used for the assessment of doses from natural, man-made environmental, medical and occupational radiation exposures, which are presented in subsequent annexes B, C, D and E respectively. The components of natural radiation (cosmic rays, terrestrial gamma rays, inhalation and ingestion) have been evaluated and added to provide an estimate of the global average exposure. Since there are wide distributions of exposures from each source, the consequent effective doses combine in various ways at each location, depending on the specific concentration of radionuclides in the environment and in the body, the latitude and altitude of the location, and many other factors. The total annual global per caput effective dose due to natural radiation sources is 2.4 mSv. A typical range of individual doses is considered to be 1-10 mSv. In any large population about 65% would be expected to have annual effective doses between 1 and 3 mSv, about 25% of the population would have annual effective doses less than 1 mSv and 10% would have annual effective doses greater than 3 mSv. The main man-made contribution to the environmental exposure of the world's population has come from the testing of nuclear weapons in the atmosphere that occurred mainly between 1945-1980. Since the previous UNSCEAR review of this topic in 1982 new information, previously classified, has become available on the numbers and yields of nuclear tests. An updated listing of atmospheric nuclear tests conducted at each of the test sites is included in this report. Although the total explosive yields of each test have been divulged, the fission and fusion yields are still mostly suppressed. Some general assumptions have been made to allow the evaluation of fission and fusion yields of each test in order to estimate the amounts of radionuclides produced in the explosions. The estimated total of fission yields of individual tests is in agreement with the global deposition of the main fission radionuclides 90Sr and 137Cs, as determined by worldwide monitoring networks. It has been calculated that the world average annual effective dose reached a peak of 150 ?Sv in 1963 and has since decreased to about 5 ?Sv in 2000, from residual radionuclides in the environment, mainly of 14C, 90Sr and 137Cs. The contribution to man-made exposures from the generation of electrical energy by nuclear power reactors has been estimated using a collective (100 year truncated) dose of 6 man-Sv per GW year. Assuming the present annual generation of 250 GW years continues, the truncated collective dose per year of practice is 1500 man-Sv to the world population, giving an estimated maximum per caput dose of less than 0.2 ?Sv per year. UNSCEAR has assessed the exposures from medical radiation procedures based on information obtaine

Monty Charles

2001-01-01T23:59:59.000Z

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121

Radiation Dose-Volume Effects in the Brain  

SciTech Connect

We have reviewed the published data regarding radiotherapy (RT)-induced brain injury. Radiation necrosis appears a median of 1-2 years after RT; however, cognitive decline develops over many years. The incidence and severity is dose and volume dependent and can also be increased by chemotherapy, age, diabetes, and spatial factors. For fractionated RT with a fraction size of <2.5 Gy, an incidence of radiation necrosis of 5% and 10% is predicted to occur at a biologically effective dose of 120 Gy (range, 100-140) and 150 Gy (range, 140-170), respectively. For twice-daily fractionation, a steep increase in toxicity appears to occur when the biologically effective dose is >80 Gy. For large fraction sizes (>=2.5 Gy), the incidence and severity of toxicity is unpredictable. For single fraction radiosurgery, a clear correlation has been demonstrated between the target size and the risk of adverse events. Substantial variation among different centers' reported outcomes have prevented us from making toxicity-risk predictions. Cognitive dysfunction in children is largely seen for whole brain doses of >=18 Gy. No substantial evidence has shown that RT induces irreversible cognitive decline in adults within 4 years of RT.

Lawrence, Yaacov Richard, E-mail: richard.lawrence@jefferson.ed [Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); El Naqa, Issam [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States); Hahn, Carol A. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC (United States); Merchant, Thomas E. [Department of Radiation Oncology, St. Jude Children's Research Hospital, Memphis, TN (United States); Dicker, Adam P. [Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA (United States)

2010-03-01T23:59:59.000Z

122

Epidemiological Studies of Leukemia in Persons Exposed to Ionizing Radiation  

Science Journals Connector (OSTI)

...exposed to ionizing radiation, the author...the higher dose range regardless...low dose range, it is emphasized...possibility of radiation hazards existing at low doses should not...exposed to ionizing radiation...exposed to ionizing radiation, the author...the higher dose range regardless...

L. H. Hempelmann

1960-01-01T23:59:59.000Z

123

Implications of Intercellular Signaling for Radiation Therapy: A Theoretical Dose-Planning Study  

SciTech Connect

Purpose: Recent in vitro results have shown significant contributions to cell killing from signaling effects at doses that are typically used in radiation therapy. This study investigates whether these in vitro observations can be reconciled with in vivo knowledge and how signaling may have an impact on future developments in radiation therapy. Methods and Materials: Prostate cancer treatment plans were generated for a series of 10 patients using 3-dimensional conformal therapy, intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy techniques. These plans were evaluated using mathematical models of survival following modulated radiation exposures that were developed from in vitro observations and incorporate the effects of intercellular signaling. The impact on dose–volume histograms and mean doses were evaluated by converting these survival levels into “signaling-adjusted doses” for comparison. Results: Inclusion of intercellular communication leads to significant differences between the signalling-adjusted and physical doses across a large volume. Organs in low-dose regions near target volumes see the largest increases, with mean signaling-adjusted bladder doses increasing from 23 to 33 Gy in IMRT plans. By contrast, in high-dose regions, there is a small decrease in signaling-adjusted dose due to reduced contributions from neighboring cells, with planning target volume mean doses falling from 74 to 71 Gy in IMRT. Overall, however, the dose distributions remain broadly similar, and comparisons between the treatment modalities are largely unchanged whether physical or signaling-adjusted dose is compared. Conclusions: Although incorporating cellular signaling significantly affects cell killing in low-dose regions and suggests a different interpretation for many phenomena, their effect in high-dose regions for typical planning techniques is comparatively small. This indicates that the significant signaling effects observed in vitro are not contradicted by comparison with clinical observations. Future investigations are needed to validate these effects in vivo and to quantify their ranges and potential impact on more advanced radiation therapy techniques.

McMahon, Stephen J., E-mail: stephen.mcmahon@qub.ac.uk [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); McGarry, Conor K. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Butterworth, Karl T. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); O'Sullivan, Joe M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Clinical Oncology, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Hounsell, Alan R. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom); Radiotherapy Physics, Northern Ireland Cancer Centre, Belfast Health and Social Care Trust, Belfast, Northern Ireland (United Kingdom); Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, Northern Ireland (United Kingdom)

2013-12-01T23:59:59.000Z

124

Radiation Effect on Microstructural Stability of RERTR Fuel  

SciTech Connect

Three depleted uranium alloys are successfully cast for the radiation stability studies of the fuel-cladding interaction product using proton irradiation. SEM analysis indicates the presence of the phases of interest: U(Si,Al)3, (U,Mo)(Si,Al)3 and a mixture of UMo2Al20, U6Mo4Al43, and UAl4. Irradiation with 2.6 MeV protons at 200ºC to the doses of 0.1, 1.0 and 3.0 dpa are carried out.

J. Gan; D. D. Keiser, Jr.; B. D. Miller; T. R. Allen; D. M. Wachs

2008-03-01T23:59:59.000Z

125

Effects of ionizing radiation on the response of certain photosensitive seeds to red light  

E-Print Network (OSTI)

and molecular oxygen. Studies of phosphate metabolism (Surrey and Gordon, 1962) and phosphorylation (Gordon and Surrey, 1961) indicate that energy transfer through phosphate esterification plays an important role and may be the key enzymatic reaction in red... spectrum promoting the germination of light-sensitive lettuce seed. Smithsonian Inst. Pubis. Misc. Collections 96: 1-8 ~ 11. Gordon, S. A. , and K. Surrey. 1961. Phosphorylation and red-spectrum photomorphogenesis. ~n Effects of ionizing radiations...

Richardson, Billy

2012-06-07T23:59:59.000Z

126

Effect of scattered radiation on sub-Doppler cooling  

Science Journals Connector (OSTI)

In this paper we discuss the effect of scattered radiation generated by a gas of cold atoms on the temperature of the gas. We show that by treating the reradiated field of the atoms as a fluctuating background field we can derive a master equation for a single atom where the effect of the surrounding medium is included in an effective relaxation operator. This relaxation operator is of second order in the interaction with the medium and in the binary-collision approximation can be written as the sum of two-body interactions with a correlation time equal to the natural lifetime of the atomic transition. The effect of the medium on the two most important sub-Doppler cooling mechanisms, Sisyphus and motion-induced orientation cooling, is investigated analytically in a one-dimensional model. In this we restrict ourselves to the limit of low saturation, weak background field and take the rate-equation limit for the collision operator. We find that both mechanisms are very sensitive to such a background field and that the temperature increases approximately as the number of atoms to the one-third power.

G. Hillenbrand; K. Burnett; C. J. Foot

1995-12-01T23:59:59.000Z

127

Evaluation of Three Somatic Genetic Biomarkers as Indicators of Low Dose Radiation Effects in Clean-up Workers of the Chernobyl Nuclear Reactor Accident  

Science Journals Connector (OSTI)

......Radiation Effects in Clean-up Workers of the Chernobyl Nuclear Reactor Accident I. M. Jones J. D. Tucker R. G. Langlois...radiation effects in clean-up workers of the Chernobyl nuclear reactor accident. | The goals of this study were to assess......

I. M. Jones; J. D. Tucker; R. G. Langlois; M. L. Mendelsohn; P. Pleshanov; D. O. Nelson

2001-09-01T23:59:59.000Z

128

Direct Effects of UV-B Radiation on the Freshwater Heterotrophic Nanoflagellate Paraphysomonas sp.  

Science Journals Connector (OSTI)

...PHYSIOLOGY Direct Effects of UV-B Radiation on the Freshwater Heterotrophic...to ambient levels of UV-B radiation can lead to death and/or...microbial ecology, vol. ISME 5. Japan Scientific Societies Press...exposed to solar ultraviolet radiation. Photochem. Photobiol. 69...

Amy L. Macaluso; David L. Mitchell; Robert W. Sanders

2009-05-08T23:59:59.000Z

129

Ionizing Radiation Effects on CMOS Imagers Manufactured in Deep Submicron Process  

E-Print Network (OSTI)

, ionizing radiation, total dose, dark current, STI, hardening by design, RHDB 1. INTRODUCTION IonizingIonizing Radiation Effects on CMOS Imagers Manufactured in Deep Submicron Process Vincent Goiffona a large dynamic range. This can significantly impact the radiation hardness of "in-pixel" devices which

Mailhes, Corinne

130

Radiation-induced bystander effect and adaptive response in mammalian cells  

E-Print Network (OSTI)

responses at low doses of radiation and have the potential to impact the shape of the dose the actual target and radiation dose effect and can contribute to our current understanding in radiation risk provide the best estimate of cancer risk over the dose range from 20 to 250 cGy. The cancer risk at doses

131

MEASUREMENT OF THE HIGH GAMMA RADIATION DOSE USING THE MEMS BASED DOSIMETER AND RADIOLISYS EFFECT  

E-Print Network (OSTI)

radiation dose. If we consider, that the average time of exploitation is estimated to be 40 years and veryMEASUREMENT OF THE HIGH GAMMA RADIATION DOSE USING THE MEMS BASED DOSIMETER AND RADIOLISYS EFFECT M of high and very high doses of ionizing radiation is crucial for the monitoring of the existing Nuclear

Boyer, Edmond

132

Biological effects in unirradiated human tissue induced by radiation damage up to 1 mm away  

E-Print Network (OSTI)

in extrapolating radiation risk estimates from epidemi- ologically accessible doses down to very low doses where) and for assessing the risk from a low-dose exposure to a carcinogen such as ionizing radiation, where only a smallBiological effects in unirradiated human tissue induced by radiation damage up to 1 mm away Oleg V

133

DUCRETE Shielding: A Cost Effective Alternative Radiation Shield  

NLE Websites -- All DOE Office Websites (Extended Search)

Summary Submitted to Spectrum 2000, Sept 24-28, 2000, Chattanooga, TN Summary Submitted to Spectrum 2000, Sept 24-28, 2000, Chattanooga, TN DUCRETE: A Cost Effective Radiation Shielding Material W. J. Quapp, Starmet CMI W. H. Miller, University of Missouri-Columbia James Taylor, Starmet CMI Colin Hundley, Starmet CMI Nancy Levoy, Starmet Corporation 1. INTRODUCTION A consequence of uranium enrichment in the US has been the accumulation of nearly 740,000 metric tons of depleted uranium hexafluoride (UF 6 ) tails. 1 While this material was once considered a feed stock for the United States Breeder Reactor Program, it is no longer needed. Alternative uses of depleted uranium are few. Some have been used for medical isotope transport casks, some for industrial radioactive source shields, some for military anti-tank

134

A parametric study of the source rate for outer radiation belt electrons using a Kalman filter  

E-Print Network (OSTI)

A parametric study of the source rate for outer radiation belt electrons using a Kalman filter Q), A parametric study of the source rate for outer radiation belt electrons using a Kalman filter, J. Geophys. Res increasingly popular to describe the outer radiation belt energetic electron environment. We use a Kalman

Li, Xinlin

135

Russian Health Studies Program - Relationship to Other Radiation...  

Office of Environmental Management (EM)

the Mayak workers had long-term exposures (10 to 30 years) to plutonium, gamma, and neutron radiation. This combination of radiation types over a working lifetime is more...

136

Second international conference on computer simulation of radiation effects in solids  

SciTech Connect

A total of 102 abstracts are included, arranged under the following headings: interatomic potentials and theoretical methods, displacement cascades and radiation effects in metals, radiation effects in semiconductors, sputtering and surface processes, cluster-solid interactions, highly charged ions and inelastic effects, and posters (A and B).

de la Rubia, T.D.; Gilmer, G.H. [comps.

1994-08-01T23:59:59.000Z

137

We can do better than effective dose for estimating or comparing low-dose radiation risks  

E-Print Network (OSTI)

We can do better than effective dose for estimating or comparing low-dose radiation risks D of exposure to different radiation fields. More commonly these days, it is used to estimate or compare radi. Keywords: Low dose risk estimation; Effective dose; Flawed definition; Effective risk 1. INTRODUCTION

Brenner, David Jonathan

138

Study on impulsive noise radiation from of gasoline direct injector  

Science Journals Connector (OSTI)

A gasoline direct injection (GDI) engine uses its own injectors for high pressure fuel supply to the combustion chamber. High frequency impact sound during the injection process is one of the main contributors to engine combustion noise. This impact noise is generated during opening and closing by an injector rod operated by a solenoid. For design of an injector with reduced noise generation it is necessary to analyze its sound radiation mechanism and propose consequent evaluation method. Spectral and modal characteristics of the injectors were measured through vibration induced by external hammer excitation. The injector modal characteristics were analyzed using a simple beam after analyzing its boundaries by complex transverse and rotational springs. To evaluate impulsive sounds more effectively Prony analysis of sounds was used for verifying influence of injector modal characteristics.

2014-01-01T23:59:59.000Z

139

Publication of New Atomic Bomb Radiation Dosimetry System  

Energy.gov (U.S. Department of Energy (DOE))

Atomic bomb dosimetry studies. The Radiation Effects Research Foundation Dosimetry System 2002 (DS02)

140

Proceedings of the ninth IEA workshop on radiation effects in ceramic insulators  

SciTech Connect

Several IEA workshops have been held over the past few years to discuss the growing number of experimental studies on the intriguing phenomenon of radiation induced electrical degradation (RIED). In the past year, several new RIED irradiation experiments have been performed which have a significant impact on the understanding of the RIED phenomenon. These experiments include a HFIR neutron irradiation experiment on 12 different grades of single- and poly-crystal alumina (450 C, {approximately}3 dpa, 200 V/mm) and several additional neutron, electron and light ion irradiation experiments. The primary objective of the IEA workshop was to review the available RIED studies on ceramic insulators. Some discussion of recent work in other areas such as loss tangent measurements, mechanical strength, etc. occurred on the final afternoon of the workshop. The IEA workshop was held in conjunction with a US-Japan JUPITER program experimenter`s workshop on dynamic radiation effects in ceramic insulators.

Zinkle, S.J.; Burn, G.L. [comps.; Hodgson, E.R.; Shikama, T.

1997-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

A Population-Based Study of the Fractionation of Postlumpectomy Breast Radiation Therapy  

SciTech Connect

Purpose: The optimal fractionation schedule of post lumpectomy radiation therapy remains controversial. The objective of this study was to describe the fractionation of post-lumpectomy radiation therapy (RT) in Ontario, before and after the seminal Ontario Clinical Oncology Group (OCOG) trial, which showed the equivalence of 16- and 25-fraction schedules. Methods and Materials: This was a retrospective cohort study conducted by linking electronic treatment records to a population-based cancer registry. The study population included all patients who underwent lumpectomy for invasive breast cancer in Ontario, Canada, between 1984 and 2008. Results: Over the study period, 41,747 breast cancer patients received post lumpectomy radiation therapy to the breast only. Both 16- and 25-fraction schedules were commonly used throughout the study period. In the early 1980s, shorter fractionation schedules were used in >80% of cases. Between 1985 and 1995, the proportion of patients treated with shorter fractionation decreased to 48%. After completion of the OCOG trial, shorter fractionation schemes were once again widely adopted across Ontario, and are currently used in about 71% of cases; however, large intercenter variations in fractionation persisted. Conclusions: The use of shorter schedules of post lumpectomy RT in Ontario increased after completion of the OCOG trial, but the trial had a less normative effect on practice than expected.

Ashworth, Allison [Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Ontario (Canada) [Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Ontario (Canada); Cancer Center of Southeastern Ontario, Kingston, Ontario (Canada); Kong, Weidong [Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Ontario (Canada)] [Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Ontario (Canada); Whelan, Timothy [Juravinski Cancer Center, Hamilton, Ontario (Canada)] [Juravinski Cancer Center, Hamilton, Ontario (Canada); Mackillop, William J., E-mail: william.mackillop@krcc.on.ca [Division of Cancer Care and Epidemiology, Queen's University Cancer Research Institute, Kingston, Ontario (Canada)

2013-05-01T23:59:59.000Z

142

Estimation of risk from medical radiation exposure based on effective and organ dose: how much difference is there?  

Science Journals Connector (OSTI)

......Russian Basic Sanitary Radiation Protection Standards...Basic Sanitary Rules for Radiation Safety of 2010(3). It is...CT)(4). Although radiation dose is the primary...effective dose; this software is addressed to radiologists......

V. K. Ivanov; V. V. Kashcheev; S. Yu. Chekin; A. N. Menyaylo; E. A. Pryakhin; A. F. Tsyb; F. A. Mettler

2013-07-01T23:59:59.000Z

143

Low Dose Radiation Research Program: Real-time Study of Signal Transduction  

NLE Websites -- All DOE Office Websites (Extended Search)

Real-time Study of Signal Transduction Pathways Involving in Real-time Study of Signal Transduction Pathways Involving in Bystander Effects Using Single Nanoparticle Optics and Single Living Cell Imaging Authors: Prakash D. Nallathamby, X. Nancy Xu, Mohan Natarajan Institutions: Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia and Department of Radiation Oncology, The University of Texas Health Science Center, San Antonio, Texas The mechanisms of bystander effects remain largely unknown. Bystander responses are thought to depend on activation of cellular communication processes. Recent studies have speculated that several crucial signal transduction pathways could play a major role in bystander effects. These crucial signal transduction pathways are controlled by a coordinated

144

Re-examining the health effects of radiation and its protection  

Science Journals Connector (OSTI)

The health effects of radiation from atomic explosions in Japan were completely different from those due to radiation from the Co-60 contaminated apartments in Taiwan. The sudden exposure to acute radiation in extremely high doses killed Japanese people, and harmed the survivors in lower doses as shown by increased cancer mortality, especially the leukemia based on the LNT model. The chronic radiation received by the residents unknowingly in the Co-60 contaminated apartments in Taiwan, even in higher doses, caused no excess cancer deaths; on the contrary their spontaneous cancer deaths were sharply reduced to only about 2.5% of that of the general population, and hereditary defects in their offspring were only 5%â??7% of those of the normal population. Therefore, the residents in the Co-60 contamination apartments had coincidently accomplished a human experiment of the health effects to human beings. The chronic radiation received from the Co-60 contaminated houses is quite similar to the radiation exposure to the workers and public in the peaceful use of nuclear energy and medical radiation. Acute radiation from a nuclear accident could harm a limited number of people, but the chronic radiation might benefit people, such as in the case of the Chernobyl accident. People should not be fearful of chronic exposure to low radiation and the traditional radiation protection policy and practices used in past 60 years should be revised based on the health effects observed in Taiwan.

Y.C. Luan; M.C. Shieh; S.T. Chen; H.T. Kung; K.L. Soong; Y.C. Yeh; T.S. Chou; W.C. Fang; S.L. Yao; C.J. Pong; S.H. Mong; J.T. Wu; J.M. Wu; H.J. Jen; W.L. Chen; W.P. Deng; M.F. Wu; M.L. Shen; C.P. Sun

2006-01-01T23:59:59.000Z

145

Biological equivalent dose studies for dose escalation in the stereotactic synchrotron radiation therapy clinical trials  

E-Print Network (OSTI)

at the European Synchrotron Radiation Facility ESRF . To estimate the possible risks, the doses receivedBiological equivalent dose studies for dose escalation in the stereotactic synchrotron radiation technique a radiation dose enhancement specific to the tumor is obtained. The tumor is loaded with a high

Boyer, Edmond

146

Direct radiative effect of aerosols emitted by transport from road, shipping and  

E-Print Network (OSTI)

Direct radiative effect of aerosols emitted by transport from road, shipping and aviation 1234567.0 License. Atmospheric Chemistry and Physics Direct radiative effect of aerosols emitted by transport: from road, shipping and aviation Y. Balkanski1, G. Myhre2,3, M. Gauss2,*, G. R�adel4, E. J. Highwood4, and K

Wirosoetisno, Djoko

147

Effects of Solar UV Radiation on Morphology and Photosynthesis of Filamentous Cyanobacterium Arthrospira platensis  

Science Journals Connector (OSTI)

...Hader. 1991. Effects of solar and ultraviolet radiation on...Garcia-Pichel, F. 1998. Solar ultraviolet and the evolutionary...estimation of their screening capacity. Appl. Environ. Microbiol...D. P. 2000. Effects of solar UV-B radiation on aquatic...

Hongyan Wu; Kunshan Gao; Virginia E. Villafañe; Teruo Watanabe; E. Walter Helbling

2005-09-01T23:59:59.000Z

148

Mutation Research 504 (2002) 91100 Bystander effects in radiation-induced genomic instability  

E-Print Network (OSTI)

Mutation Research 504 (2002) 91­100 Bystander effects in radiation-induced genomic instability recombination and other phenotypes associated with genomic instability. © 2002 Elsevier Science B.V. All rights reserved. Keywords: Bystander effects; Genomic instability; Ionizing radiation 1. Introduction Exposure

149

Low-temperature catalyst activator: mechanism of dense carbon nanotube forest growth studied using synchrotron radiation  

Science Journals Connector (OSTI)

The mechanism of dense vertically aligned carbon nanotube growth achieved by a recently developed thermal chemical vapor deposition method was studied using synchrotron radiation spectroscopic techniques.

Takashima, A.

2014-05-22T23:59:59.000Z

150

Effects of ultraviolet radiation on trophic interactions not detected?  

Science Journals Connector (OSTI)

ambient solar ultraviolet (UV) radiation on periphyton and grazers in a ... As a result of varying solar angles, both eleva- ..... Edmonton, Alberta, Canada T6G 2E9.

1999-03-11T23:59:59.000Z

151

Health effects of low-level radiation in shipyard workers. Final report: [Draft  

SciTech Connect

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

Matanoski, G.M.

1991-06-01T23:59:59.000Z

152

Pitch angle distribution analysis of radiation belt electrons based on Combined Release and Radiation Effects Satellite  

E-Print Network (OSTI)

Pitch angle distribution analysis of radiation belt electrons based on Combined Release of pitch angle distributions (PADs) of energetic electrons is performed. The distributions are classified a is the local pitch angle, a profile of the parameter n versus L-shell is produced for local times corresponding

Li, Xinlin

153

EPIDEMIOLOGICAL STUDIES ON RADIATION CARCINOGENESIS IN HUMAN POPULATIONS FOLLOWING ACUTE EXPOSURE: NUCLEAR EXPLOSIONS AND MEDICAL RADIATION  

E-Print Network (OSTI)

estimation of the carcinogenic of low-dose, low-LET radiationradiation uoses, close rates, and LET to enable risk tions occur estimation at doses,radiation-induced cancer necessarily be based primarily on human dose-incidence data. in man must However, risk estimation

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

154

Commemoration of the 60th Annniversary of The Atomic Bomb Casualty Commission/Radiation Effects Research Foundation  

Energy.gov (U.S. Department of Energy (DOE))

Commemoration of the 60th Annniversary of The Atomic Bomb Casualty Commission/Radiation Effects Research Foundation (ABCC/RERF)

155

Heat transfer through a water spray curtain under the effect of a strong radiative source  

E-Print Network (OSTI)

Heat transfer through a water spray curtain under the effect of a strong radiative source P. Boulet - mail Pascal.Boulet@lemta.uhp-nancy.fr Keywords : heat transfer, radiative transfer, vaporization, convection, water spray Abstract Heat transfer inside a participating medium, made of droplets flowing in gas

Paris-Sud XI, Université de

156

Accuracy of Humidity Measurement on Ships: Consideration of Solar Radiation Effects  

Science Journals Connector (OSTI)

The effect of heating due to solar radiation on measurements of humidity obtained from ships is examined. Variations in wet- and dry-bulb temperature measured on each side of a research ship are shown to correlate with solar radiation. However, ...

Elizabeth C. Kent; Peter K. Taylor

1996-12-01T23:59:59.000Z

157

The Effects of High Dose Rates of Ionizing Radiations on Solutions of Iron and Cerium Salts  

Science Journals Connector (OSTI)

...research-article The Effects of High Dose Rates of Ionizing Radiations on Solutions of Iron and Cerium...of 1.3 duration and over a range of dose rates from 0.5 to 20 000 rads/pulse. Radiation yields at constant dose rate...

1960-01-01T23:59:59.000Z

158

CASING EFFECTS ON THE RADIATION PERFORMANCE OF A CIRCULARLY POLARIZED PATCH ANTENNA  

E-Print Network (OSTI)

CASING EFFECTS ON THE RADIATION PERFORMANCE OF A CIRCULARLY POLARIZED PATCH ANTENNA K. Rambabu, H on the radiation characteristics of a miniaturized patch antenna for circular polarization. Different scenarios DESIGN Using a multiple resonance technique [4] for broadband performance, a circularly polarized patch

Bornemann, Jens

159

X-ray radiation effects in multilayer epitaxial graphene Jeremy Hicks1  

E-Print Network (OSTI)

1 X-ray radiation effects in multilayer epitaxial graphene Jeremy Hicks1 , Rajan Arora2 , Eleazar and after exposure to a total ionizing dose (TID) of 12 Mrad(SiO2) using a 10 keV X-ray source. While we are mostly unaffected by radiation exposure. Combined with X-ray photoelectron spectroscopy (XPS) data

160

Microsoft PowerPoint - htalk324_radiation_effects09aug051.ppt  

National Nuclear Security Administration (NNSA)

Electrical Effects of Ionizing Electrical Effects of Ionizing Radiation on Insulating Materials Harold P. Hjalmarson, Rudolph E. Magyar and Kenneth E. Kambour Sandia National Laboratories Albuquerque, NM 87185 AMS Conference August 24-28, 2009 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000. 2 Radiation Effects: Evolution from Atomistic to Continuum Phenomena Time-Dependent Density Functional Theory (TDDFT): Rudy Magyar Two-Temperature Molecular Dynamics (MD): Paul Crozier Radiation Effects in Oxides and Semiconductors (REOS): HPH 3 Outline * Overview * Radiation Effects - Electronic cooling (TDDFT & REOS) - Atomic Rearrangement (MD & REOS)

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Radiation Physics and Chemistry 71 (2004) 363368 A study of the alanine dosimeter irradiation temperature  

E-Print Network (OSTI)

. Puhla , Anna L. McBainb , Glenn W. Calvertb a Ionizing Radiation Division, Physics Laboratory, National. Since the temperature coefficient is known to be dose dependent [Radiat. Phys. Chem. 57 (2000) 1], a series of dose response studies were conducted over a dose range of 0.5­100 kGy. The study revealed

162

Are synchroton radiation studies (including EXAFS) breakthroughs in structurals studies of metalloproteins?  

Science Journals Connector (OSTI)

Electrons travelling around storage rings in vacuum at close to the speed of light are being exploited to an increasing extent by bioinorganic chemists. These electrons emit intense radiation ranging from the infrared through X-ray regions. The radiation is continuous in energy, pulsed, polarized, and of intensity not otherwise obtainable for comparable time periods. The availability of the synchrotron radiation has elicited an increasing variety of absorption and scattering techniques. The absorption edge, the X-ray Absorption Near Edge Structure (XANES) and the Extended X-ray Absorption Fine Structure (EXAFS) have each been exploited as have scattering techniques. This discussion brings together from four countries (and four synchrotron sources) some of the major proponents and users of synchrotron radiation. The round table will entail short (20–25 minutes) formal presentations by each of the 5 participants in which they will seek not only to expose their own work but also to put it in the context of the full impact of synchrotron radiation studies. Short question periods will follow each talk and a final period will be left for discussion among the panelists, further questions from the audience and summing up. To start the session, Cramer will introduce the synchrotron sources and radiation characteristics, discuss absorption applications to nitrogenase, hemoglobin and cytochrome oxidase and describe some of the future novel ways of exploiting the characteristics of the radiation. Stuhrmann will continue this line by describing the hierarchy of information one gets from absorption and scattering experiments and he will review applications of scattering to such systems as ferritin, hemoglobin and t-RNA. Teo will emphasize the detailed information obtainable from EXAFS and will discuss its application to Fe systems in nitrogenase and 3Fe?3S cluster systems. Bianconi will focus on the information attainable from XANES as compared to EXAFS and will discuss applications of XANES to hemoglobin and calmodulin structure. Finally, Garner will discuss some of the EXAFS analysis protocols and their limits and will analyze recent data from superoxide dismutase and metallothionein Between them our distinguished panelists should cover many of the established and emerging synchrotron techniques as well as their application to systems containing Fe, Cu, Zn, Mo, Ca, Mg, Cs, I and Tb. The panelists and convener are committed to pedagogical presentations, lacking in undefined jargon and abbreviations. We will endeavor to convey an appreciation for the powers and limits of the various techniques. If we do our job well, the answer to the question posed in the title of the Round Table should become obvious to the audience.

E.I. Stiefel

1983-01-01T23:59:59.000Z

163

Surface effects on the radiation response of nanoporous Au foams  

SciTech Connect

We report on an experimental and simulation campaign aimed at exploring the radiation response of nanoporous Au (np-Au) foams. We find different defect accumulation behavior by varying radiation dose-rate in ion-irradiated np-Au foams. Stacking fault tetrahedra are formed when np-Au foams are irradiated at high dose-rate, but they do not seem to be formed in np-Au at low dose-rate irradiation. A model is proposed to explain the dose-rate dependent defect accumulation based on these results.

Fu, E. G.; Caro, M.; Wang, Y. Q.; Baldwin, K.; Caro, A. [Materials Science in Radiation and Dynamics Extremes, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Zepeda-Ruiz, L. A. [Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94551 (United States); Bringa, E. [CONICET and Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza 5500 (Argentina); Nastasi, M. [Nebraska Center for Energy Sciences Research, University of Nebraska-Lincoln, Lincoln, Nebraska 68508 (United States)

2012-11-05T23:59:59.000Z

164

Radiation Dose-Volume Effects in the Heart  

SciTech Connect

The literature is reviewed to identify the main clinical and dose-volume predictors for acute and late radiation-induced heart disease. A clear quantitative dose and/or volume dependence for most cardiac toxicity has not yet been shown, primarily because of the scarcity of the data. Several clinical factors, such as age, comorbidities and doxorubicin use, appear to increase the risk of injury. The existing dose-volume data is presented, as well as suggestions for future investigations to better define radiation-induced cardiac injury.

Gagliardi, Giovanna, E-mail: giovanna.gagliardi@karolinska.s [Department of Medical Physics, Karolinska University Hospital and Karolinska Institute, Stockholm (Sweden); Constine, Louis S. [Department of Radiation Oncology, University of Rochester Cancer Center, Rochester, NY (United States); Moiseenko, Vitali [Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Correa, Candace; Pierce, Lori J. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Allen, Aaron M. [Department of Radiation Oncology, Dana- Farber Cancer Institute, Boston, MA (United States); Rabin Medical Center Petach Tikvah (Israel); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina, Chapel Hill, NC (United States)

2010-03-01T23:59:59.000Z

165

Clear Skies A Study of Longwave Radiation Codes for Climate Studies...  

NLE Websites -- All DOE Office Websites (Extended Search)

the outcome of this approach will provide both a better longwave radiative forcing algorithm and a better understanding of how longwave radiative forcing influences the...

166

Solar irradiance changes and photobiological effects at Earth's surface following astrophysical ionizing radiation events  

E-Print Network (OSTI)

Astrophysical ionizing radiation events have been recognized as a potential threat to life on Earth, primarily through depletion of stratospheric ozone and subsequent increase in surface-level solar ultraviolet radiation. Simulations of the atmospheric effects of a variety of events (such as supernovae, gamma-ray bursts, and solar proton events) have been previously published, along with estimates of biological damage at Earth's surface. In this work, we employed the TUV radiative transfer model to expand and improve calculations of surface-level irradiance and biological impacts following an ionizing radiation event. We considered changes in surface-level UVB, UVA, and photosynthetically active radiation (visible light) for clear-sky conditions and fixed aerosol parameter values. We also considered a wide range of biological effects on organisms ranging from humans to phytoplankton. We found that past work overestimated UVB irradiance, but that relative estimates for increase in exposure to DNA damaging radi...

Thomas, Brian C; Snyder, Brock R

2015-01-01T23:59:59.000Z

167

Third Radiation Effects Research Foundation Board of Councilors Meeting Held in Hiroshima  

Energy.gov (U.S. Department of Energy (DOE))

The third Board of Councilors (BOC) meeting was held on June 18-19 at the Hiroshima Radiation Effects Research Foundation (RERF), a bi-national U.S.-Japan research organization.

168

Genomic instability and bystander effects induced by high-LET radiation Eric J Hall*,1  

E-Print Network (OSTI)

Genomic instability and bystander effects induced by high-LET radiation Eric J Hall*,1 and Tom K. There is a progressive increase in genomic instability, determined either by gene amplification or allelic imbalance

169

Effect of surface treatments on radiation buildup in steam generators  

SciTech Connect

Test coupons of typical PWR materials of construction were prepared using a number of pretreatments to minimize radiation buildup. The coupons were then exposed to primary coolant at the Doel-2 PWR in Belgium. The exposure periods for the coupons ranged from one to three fuel cycles. After removal from the primary system, doserate and gamma spectroscopy measurements were made to determine the radioactivity levels on the coupons. Varying levels of success were achieved for the preconditioning techniques tested. Electropolishing alone provided some degree of resistance to radiation buildup on the treated surface and electropolishing plus passivation was shown to be even better. Radiation buildup resistance of the palladium-coated coupons was poor; radiation levels on these coupons were even higher than on the untreated reference coupons. The poor performance of the palladium-coated coupons was possibly due to the method used to apply the coating. In contrast to palladium coating, very encouraging results were achieved with chromium plating plus passivation. Preliminary results show that this technique can inhibit activity deposition by as much as a factor of ten. 4 refs., 64 figs., 26 tabs.

Asay, R.H. (Radiological and Chemical Technology, Inc., Santa Clara, CA (United States)); Pick, M.E. (Nuclear Electric plc, Berkeley (United Kingdom). Berkeley Nuclear Labs.); Roofthooft, R. (Laboratoire Belge de l'Industrie Electrique (LABORELEC), Linkebeek (Belgium)); van Melsen, C. (Energy Invest, Beersel (Belgium))

1991-11-01T23:59:59.000Z

170

Radioprotective Effects of Melatonin on Radiation-Induced Cataract  

Science Journals Connector (OSTI)

......of radiation bred at Atat rk University Medical School, Department of Pharma- cology...automatic tem- perature (22 1 C) and lighting controls (12 hr light / 12 hr dark...prolongation of survival at reasonable cost to cancer patients.24) But, cataract......

Ihsan Karslioglu; Mustafa Vecdi Ertekin; Seyithan Taysi; Ibrahim Koçer; Orhan Sezen; Akçahan Gepdiremen; Mehmet Koç; Nuri Bakan

2005-06-01T23:59:59.000Z

171

Effects of heat and radiation on mammalian cells  

Science Journals Connector (OSTI)

Although it is tempting to interpret the actions of heat on living cells as a way of oxidative stress, the well known naturally occuring antioxidant systems (reduced glutathione, superoxide dismutase, catalase and glutathione peroxidase) are not found to act as the main protective systems of the cell against hyperthermic cell killing. Evidence is presented that it is not the lipids of the membrane, but probably the membrane proteins which are critical primary molecular targets for hyperthermia. The readily peroxidizable polyunsaturated fatty acyl (PUFA) chains of phospholipids may be target molecules for radiation damage leading to interphase death but not leading to reproductive death. Repair of radiation-induced DNA lesions is probably the critical event in cell survival after radiation. This process is inhibited by hyperthermia. The synergism observed as a consequence of the interaction of heat and radiation may not always be explained by the rate of repair of DNA breaks. Especially in the case of fractioned heat treatments (inducing a state of thermotolerance) the situation seems more complicated. Heat-induced inactivation of DNA repair enzymes as well as heat-induced structural changes in chromatin (enhanced protein binding) may be processes that become critical. Thermotolerance does not always interfere with the process of heat radiosensitization.

A.W.T. Konings

1987-01-01T23:59:59.000Z

172

The Doppler Effect in the Molecular Scattering of Radiation  

Science Journals Connector (OSTI)

... the irregular alterations in the wave-length of the scattered radiation produced (in accordance with Doppler's principle) by the thermal movements of the molecules. There is one interesting feature ... ) by the thermal movements of the molecules. There is one interesting feature of the Doppler ...

C. V. RAMAN

1919-05-01T23:59:59.000Z

173

Effect of gamma radiation on selected functional and physical properties of liquid egg white  

E-Print Network (OSTI)

had larger air cells with thicker cell walls. The cakes were also tougher and had more resistance to compression. CHAPTER I II EFFECT OF GAMMA RADIATION ON SELECTED PHYSICAL PROPERTIES OF LIqUID EGG WHITE Intr oduct ion As indi. cated in Chapter... EFFECT OF GAMMA RADIATION ON SELECTED FUNCTIONAL AND PHYSICAL PROPERTIES OF LIQUID EGG WHITE A Thesis By Hershell Ray Ball, Jr. Approved as to style and content by) (Chairman of Committee) ead of Department) (Me mba (Member) ( ber) ~Ja...

Ball, Hershell Ray

1966-01-01T23:59:59.000Z

174

Effects of neutron radiation on power silicon diodes at low temperatures  

E-Print Network (OSTI)

. Watson (Member) Fre ertck R. Huson (Member) Ohannes Eknoyan (Member) . W. Howze (Head of Department) May 1991 ABSTRACT Effects of Neutron Radiation on Power Silicon Diodes at Low Temperatures. (May 1991) Kevin J. English, B. S. , University... OF SCIENCE May 1991 Major Subject: Electrical Engineering EFFECTS OF NEUTRON RADIATION ON POWER SILICON DIODES AT LOW TKvPERATURES A Thesis by KEVIN JOSEPH ENGLISH Approved as to style and content by: Mark H. Weichold (Chair of Committee) Karan L...

English, Kevin Joseph

2012-06-07T23:59:59.000Z

175

Radiation exposure assessment for portsmouth naval shipyard health studies  

Science Journals Connector (OSTI)

......of radiation worker cohorts employed...Hanford Site, Oak Ridge National Laboratory...Canada (AECL) workers from the Chalk...squares) between 1950 and 1996. DISCUSSION...for 13,468 workers with PNS exposure...assignments before and after adjustments......

R. D. Daniels; T. D. Taulbee; P. Chen

2004-09-01T23:59:59.000Z

176

"We will die and become science" : the production of invisibility and public knowledge about Chernobyl radiation effects in Belarus  

E-Print Network (OSTI)

estimation of late effects was based on the actual doses in the Soviet scientists argued that health effects caused by radiation

Kuchinskaya, Olga

2007-01-01T23:59:59.000Z

177

Radiation exposure and central nervous system cancers: A case-control study among workers at two nuclear facilities  

SciTech Connect

A nested case-control study was conducted among workers employed between 1943 and 1977 at two nuclear facilities to investigate the possible association of primary malignant neoplasms of the central nervous system (CNS) with occupational exposure to ionizing radiation from external and internal sources. Eighty-nine white male and female workers, who according to the information on death certificates dies of primary CNS cancers, were identified as cases. Four matched controls were selected for each case. External radiation exposure data were available from film badge readings for individual workers, whereas radiation dose to lung from internally deposited radionuclides, mainly uranium, was estimated from area and personnel monitoring data and was used in analyses in lieu of the dose to the brain. Matched sets were included in the analyses only if information was available for the case and at least one of the corresponding controls. Thus, the analyses of external radiation included 27 cases and 90 matched controls, and 47 cases and 120 matched controls were analyzed for the effects of radiation from internally deposited uranium. No association was observed between deaths fron CNS cancers and occupational exposure to ionizing radiation from external or internal sources. However, due to the small number of monitored subjects and low doses, a weak association could not be ruled out. 43 refs., 1 fig., 15 tabs.

Carpenter, A.V.; Flanders, W.D.; Frome, E.L.; Crawford-Brown, D.J.; Fry, S.A.

1987-03-01T23:59:59.000Z

178

Study on technology of electromagnetic radiation of sensitive index to forecast the coal and gas hazards  

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Hazard forecast of coal and gas outburst was an important step of comprehensive outburst-prevention measures. Aiming at the manifestation of disaster threatens such as the gas outburst to mine safety, this paper explained the forecasting principles of electromagnetic radiation to coal and gas outburst, by the electromagnetic radiation theory of coal rock damage; it studied the characteristics and rules of electromagnetic radiation during the deformation and fracture process of loaded coal rocks, and confirmed forecast sensitive indexes of electromagnetic radiation as well as its critical values by signals of electromagnetic radiation. By applying EMR monitoring technology in the field, outburst prediction and forecast tests to the characteristics of electromagnetic radiation during the driving process was taken, and figured out the hazard prediction values by using forecast methods of static and dynamic trend.

Yuliang Wu; Wen Li

2010-01-01T23:59:59.000Z

179

Microwave influence on the isolated heart function. 2: Combined effect of radiation and some drugs  

SciTech Connect

The combined effects of microwave radiation and some drugs were studied in an isolated frog auricle preparation. The experiments established that exposure to pulse-modulated 915 Mhz microwaves for up to 40 min had no effect on either the rate or the amplitude of spontaneous auricle twitches, unless the average absorbed power was high enough to produce preparation heating. Treatment of the preparation with saline containing (0.6--3.0) 10{sup {minus}5} M of propranolol or (0.5--1.5) 10{sup {minus}7} M of atropine altered neither its pacemaker nor its contractile functions; these drugs also had no effect when they were combined with nonthermal microwave irradiation. Caffeine (1 mM) strongly increased the average heart power, which was calculated as the product of twitch rate ad amplitude. The caffeine effect appeared to be significantly augmented (by about 15%, P<0.02) under exposure to burst-type pulsed microwaves (pulse width, 1.5 msec; pause, 2.5 msec; 8 pulses/burst, 16 bursts/s; average SAR, 8--10 W/kg). By itself, this modulation was not effective; the heating of the preparation and saline during exposure was approximately 0.1 C, which could not account for the detected changes. The experimental results demonstrate that caffeine treatment increases the microwave sensitivity of the frog auricle preparation and reveals primarily subthreshold, nonthermal microwave effect.

Pakhomov, A.G.; Dubovick, B.V.; Degtyariov, I.G.; Pronkevich, A.N. [Russian Academy of Medical Sciences, Obninsk (Russian Federation). Medical Radiology research Center

1995-09-01T23:59:59.000Z

180

Study of Emission TurbulenceRadiation Interaction in Hypersonic Boundary Layers  

E-Print Network (OSTI)

Study of Emission Turbulence­Radiation Interaction in Hypersonic Boundary Layers L. Duan and M. P of emission turbulence­radiation interaction in hypersonic turbulent boundary layers, representative interaction between turbulence and emission at the hypersonic environment under investigation. An explanation

Martín, Pino

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections  

NLE Websites -- All DOE Office Websites (Extended Search)

Estimating Three-Dimensional Cloudy Radiative Transfer Estimating Three-Dimensional Cloudy Radiative Transfer Effects from Time-Height Cross Sections C. Hannay and R. Pincus National Oceanic and Atmospheric Administration Climate Diagnostics Center Boulder, Colorado K. F. Evans Program in Atmospheric and Oceanic Sciences University of Colorado Boulder, Colorado Introduction Clouds in the atmosphere are finite in extent and variable in every direction and in time. Long data sets from ground-based profilers, such as lidars or cloud radars, could provide a very valuable set of observations to characterize this variability. We may ask how well such profiling instruments can represent the cloud structure as measured by the magnitude of the three-dimensional (3D) radiative transfer effect. The 3D radiative transfer effect is the difference between the domain average broadband solar surface

182

Cell type dependent radiation induced signaling and its effect on tissue regulation  

NLE Websites -- All DOE Office Websites (Extended Search)

Cell type dependent radiation induced signaling and its effect on tissue regulation Cell type dependent radiation induced signaling and its effect on tissue regulation Marianne B. Sowa, Claere von Neubeck, R. Joe Robinson, Paula M. Koehler, Norman J. Karin, Xihai Wang, Katrina M. Waters and Harish Shankaran Ionizing radiation exposure triggers a cell signaling program which includes proliferation, the DNA damage response, and tissue remodeling. The activated signaling pathways lead to the induction of both protective effects as well as adverse consequences. A fundamental question is whether signaling cascades initiated by low doses are fundamentally different than those initiated by high doses. To address this question we have applied a systems biology approach to examine the radiation induced temporal responses of an in vitro three dimensional (3D) human skin tissue model. Using microarray-

183

Effects of UV-B Radiation and Periodic Desiccation on the Morphogenesis of the Edible Terrestrial Cyanobacterium Nostoc flagelliforme  

Science Journals Connector (OSTI)

...Microbial Ecology Effects of UV-B Radiation and Periodic Desiccation on...flagelliforme under low UV-B radiation and periodic desiccation...Nikon Corporation, Tokyo, Japan). RESULTS Effects of UV-B...regardless of 0.1 W m2 UV-B radiation (Fig. 3a). Furthermore...

Yan-Na Feng; Zhong-Chun Zhang; Jun-Li Feng; Bao-Sheng Qiu

2012-08-03T23:59:59.000Z

184

Radiation therapy of pediatric brain tumors : comparison of long-term health effects and costs between proton therapy and IMRT  

E-Print Network (OSTI)

Radiation therapy is an important component of pediatric brain tumor treatment. However, radiation-induced damage can lead to adverse long-term health effects. Proton therapy has the ability to reduce the dose delivered ...

Vu, An T. (An Thien)

2011-01-01T23:59:59.000Z

185

Low Dose Radiation Program: Links - Agencies with Radiation Regulatory  

NLE Websites -- All DOE Office Websites (Extended Search)

Agencies with Radiation Regulatory Concerns and Involvement Agencies with Radiation Regulatory Concerns and Involvement Biological Effects of Low Level Exposures (BELLE) Canadian Nuclear Safety Commission Center for Risk Excellence Health Protection Agency The Health Risks of Extraterrestrial Environments International Commission on Radiation Units and Measurements, Inc. International Commission on Radiological Protection (ICRP) International Radiation Protection Association (IRPA) NASA Space Radiation Program National Academy of Sciences (NAS) Nuclear and Radiation Studies Board National Aeronautics and Space Administration (NASA) NASA OBRR Task Book Publication National Council on Radiation Protection (NCRP) National Institute of Environmental Health Sciences (NIEHS) National Toxicology Program (NTP) Occupational Safety and Health Administration (OSHA)

186

Direct Radiative Effect of Mineral Dust on the Development of African Easterly Waves in Late Summer, 2003-07  

SciTech Connect

Episodic events of both Saharan dust outbreaks and African easterly waves (AEWs) are observed to move westward over the eastern tropical Atlantic Ocean. The relationship between the warm, dry, and dusty Saharan air layer on the nearby storms has been the subject of considerable debate. In this study, the Weather Research and Forecasting model is used to investigate the radiative effect of dust on the development of AEWs during August and September, the months of maximumtropical cyclone activity, in years 2003–07. The simulations show that dust radiative forcing enhances the convective instability of the environment. As a result, mostAEWsintensify in the presence of a dust layer. The Lorenz energy cycle analysis reveals that the dust radiative forcing enhances the condensational heating, which elevates the zonal and eddy available potential energy. In turn, available potential energy is effectively converted to eddy kinetic energy, in which local convective overturning plays the primary role. The magnitude of the intensification effect depends on the initial environmental conditions, including moisture, baroclinity, and the depth of the boundary layer. The authors conclude that dust radiative forcing, albeit small, serves as a catalyst to promote local convection that facilitates AEW development.

Ma, Po-Lun; Zhang, Kai; Shi, Jainn Jong; Matsui, Toshihisa; Arking, Albert

2012-12-19T23:59:59.000Z

187

Nuclear bremsstrahlung and its radiation effects in fusion reactors  

Science Journals Connector (OSTI)

Nucleons, i.e. protons or neutrons, are emitted in many fusion processes of light nuclei. The fusion-generated nucleons can in turn fuse with or be captured by an un-reacted nuclear fuel, for example deuterium. The fusion reaction occurs at an average center of mass (COM) energy of 10?keV (thousand electron volts) or more in a typical fusion reactor. At such a relative low COM energy, the proton and deuteron are in a state where the relative angular momentum approaches zero, or an s-wave state. The single gamma radiation process is thus suppressed due to the conservation of parity. Instead, the gamma ray (typically of the order of a few MeV or more) released is likely to be accompanied by soft x-ray photons from a nuclear bremsstrahlung process, which generates continuous x-ray radiation peaked around a few hundred eV to a few keV. The average photon energy and spectrum properties of such a process is calculated with a semiclassical approach. This phenomenon may cause additional parasitic issues to a fusion reactor, while also opening up the possibility of new plasma diagnostics.

Nie Luo; Magdi Ragheb; George H Miley

2009-01-01T23:59:59.000Z

188

Experimental and theoretical study of red-shifted solitonic resonant radiation in photonic crystal fibers and generation of radiation seeded Raman solitons  

E-Print Network (OSTI)

The red shifted solitonic resonant radiation is a fascinating phase matching phenomenon that occurs when an optical pulse, launched in the normal dispersion regime of photonic crystal fiber, radiates across the zero dispersion wavelength. The formation of such phase-matched radiation is independent of the generation of any optical soliton and mainly governed by the leading edge of input pump which forms a shock front. The radiation is generated at the anomalous dispersion regime and found to be confined both in time and frequency domain. We experimentally investigate the formation of such radiations in photonic crystal fibers with detailed theoretical analysis. Our theoretical predictions corroborate well with experimental results. Further we extend our study for long length fiber and investigate the interplay between red-shifted solitonic resonant radiation and intrapulse Raman scattering (IPRS). It is observed that series of radiation-seeded Raman solitons are generated in anomalous dispersion regime.

Bose, Surajit; Chattopadhyay, Rik; Pal, Mrinmay; Bhadra, Shyamal K

2015-01-01T23:59:59.000Z

189

Low Dose Ionizing Radiation and HZE Particle Effects on Adult Hippocampal  

NLE Websites -- All DOE Office Websites (Extended Search)

and HZE Particle Effects on Adult Hippocampal and HZE Particle Effects on Adult Hippocampal Neurogenesis and mRNA Expression Kerry O'Banion University of Rochester School of Medicine & Dentistry Abstract Most of our knowledge about low dose radiation effects relates to DNA damage and chromosomal aberrations that result in cell death or alterations in genetic programs leading to malignancy. In addition To direct DNA damage, there is accumulating evidence that radiation induced alterations in the microenvironment can have significant effects on programs of cell replication and differentiation such as neurogenesis in adult mammalian brain. Adult neurogenesis in the hippocampus is postulated to play an important role in learning and memory and manipulations that alter neurogenesis, including inhibition following radiation exposure, have been

190

Direct and semi-direct radiative effects of anthropogenic aerosols in the Western United States: Seasonal  

E-Print Network (OSTI)

a regional climate model (RCM) in conjunction with the aerosol fields from a GEOS-Chem chemical- transport emissions and the seasonal low-level winds. The RCM-simulated anthropogenic aerosol radiative effects vary, respectively, following the seasonal AOD. In Arizona-New Mexico (AZNM), the effect of anthropogenic sulfates

Liou, K. N.

191

Net radiative effect of dust aerosols from satellite measurements over Sahara  

E-Print Network (OSTI)

's Radiant Energy System (CERES) to calculate the top-of-atmosphere SW and LW flux radiative effect due to oceans where the shortwave effect dominates. Citation: Yang, E.-S., P. Gupta, and S. A. Christopher (2009 of aerosols, space-borne sensors use information from the ultraviolet (UV) to the visible and thermal infrared

Christopher, Sundar A.

192

Radiative-Convective Equilibrium Revisited: the Greenhouse Effect of Clouds  

Science Journals Connector (OSTI)

A parameterized spectral radiative-convective equilibrium model is built and the heating rates and temperature profiles for various absorbers are calculated and compared with the results of a classical model. Then using an optical depth that is dependent on both the extinction coefficient and the cloud-water path the validity of the black-cloud assumption is tested. It is determined under what conditions one would need to know the liquid or ice water path of the cloud and when one can simply treat the cloud as a black object. A distribution of both ice and water clouds is inputted into the model and the global average surface temperature is obtained. The sensitivity of the surface temperature to a change in either the ice or liquid water path of the cloud is also evaluated.

R. Davies; C. Radley

2009-01-01T23:59:59.000Z

193

A Study of Longwave Radiation Codes for Climate Studies: Validation with ARM Observations and Tests in General Circulation Models  

SciTech Connect

One specific goal of the Atmospheric Radiation Measurements (ARM) program is to improve the treatment of radiative transfer in General Circulation Models (GCMs) under clear-sky, general overcast and broken cloud conditions. Our project was geared to contribute to this goal by attacking major problems associated with one of the dominant radiation components of the problem --longwave radiation. The primary long-term project objectives were to: (1) develop an optimum longwave radiation model for use in GCMs that has been calibrated with state-of-the-art observations for clear and cloudy conditions, and (2) determine how the longwave radiative forcing with an improved algorithm contributes relatively in a GCM when compared to shortwave radiative forcing, sensible heating, thermal advection and convection. The approach has been to build upon existing models in an iterative, predictive fashion. We focused on comparing calculations from a set of models with operationally observed data for clear, overcast and broken cloud conditions. The differences found through the comparisons and physical insights have been used to develop new models, most of which have been tested with new data. Our initial GCM studies used existing GCMs to study the climate model-radiation sensitivity problem. Although this portion of our initial plans was curtailed midway through the project, we anticipate that the eventual outcome of this approach will provide both a better longwave radiative forcing algorithm and from our better understanding of how longwave radiative forcing influences the model equilibrium climate, how improvements in climate prediction using this algorithm can be achieved.

Robert G. Ellingson

2004-09-28T23:59:59.000Z

194

Neutron and gamma radiation effects in proton exchanged optical waveguides  

Science Journals Connector (OSTI)

The effect of neutron and gamma ray irradiations on the optical properties of proton exchanged Z-cut lithium niobate optical planar waveguides were investigated. The damage thresholds...

Passaro, Vittorio; Armenise, Mario

2002-01-01T23:59:59.000Z

195

Review and evaluation of updated research on the health effects associated with low-dose ionising radiation  

Science Journals Connector (OSTI)

......studies of radiation workers, such as the Rocketdyne(149), Mayak(150, 151) and National...occupational studies is not known. Rocketdyne study-other studies of radiation workers...in the 15-country study include the Rocketdyne study(149). By itself, this study......

Lawrence T. Dauer; Antone L. Brooks; David G. Hoel; William F. Morgan; Daniel Stram; Phung Tran

2010-07-01T23:59:59.000Z

196

JLab, College of W&M researchers study radiation blockers...  

NLE Websites -- All DOE Office Websites (Extended Search)

is needed to protect small animals effectively from radioactive iodide in medical imaging procedures. The long-term animal nuclear imaging project is being conducted by a...

197

The Doppler Effect in the Molecular Scattering of Radiation  

Science Journals Connector (OSTI)

... be impossible. It is involved in this remark that each molecule will exert its full effect on the index of refraction, however irregular the distribution may be, provided it is ... molecules will obstruct each other; and, moreover, the thermal motions will not disturb this effect. The specially favoured directions, for disturbances passed on by the molecules, must be ...

JOSEPH LARMOR

1919-05-01T23:59:59.000Z

198

Effect of HZE radiation and diets rich in fiber and n-3 poly unsaturated fatty acids (n-3 PUFA) on colon cancer in rats  

E-Print Network (OSTI)

weeks earlier and at the end of the study had morbidity/mortality rate 14.2% higher (P=0.0005) than non-irradiated rats. There was no significant effect of HZE radiation on colon cancer incidence. The effects of dietary fibers and oils on health state...

Glagolenko, Anna Anatolievna

2006-08-16T23:59:59.000Z

199

Neutron degeneracy and plasma physics effects on radiative neutron captures in neutron star crust  

Science Journals Connector (OSTI)

We consider the astrophysical reaction rates for radiative neutron capture reactions (n,?) in the crust of a neutron star. The presence of degenerate neutrons at high densities (mainly in the inner crust) can drastically affect the reaction rates. Standard rates assuming a Maxwell-Boltzmann distribution for neutrons can underestimate the rates by several orders of magnitude. We derive simple analytical expressions for reaction rates at a variety of conditions with account for neutron degeneracy. We also discuss the plasma effects on the outgoing radiative transition channel in neutron radiative capture reactions and show that these effects can also increase the reaction rates by a few orders of magnitude. In addition, using detailed balance, we analyze the effects of neutron degeneracy and plasma physics on reverse (?,n) photodisintegration. We discuss the dependence of the reaction rates on temperature and neutron chemical potential and outline the efficiency of these reactions in the neutron star crust.

P. S. Shternin; M. Beard; M. Wiescher; D. G. Yakovlev

2012-07-24T23:59:59.000Z

200

Radiation Effects on Low-dimensional Carbon System  

E-Print Network (OSTI)

Ion irradiation has been known to be an effective tool for structure modification with micro/nano-scale precision. Recently, demonstrations have been made for nano-machining, such as the cutting and welding of carbon nanotubes. Understanding...

Wang, Jing

2013-08-05T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Human radiation studies: Remembering the early years. Oral history of biophysicist Cornelius A. Tobias, Ph.D., January 16, 1995  

SciTech Connect

Dr. Cornelius A. Tobias was interviewed by representatives of US DOE Office of Human Radiation Experiments (OHRE). He was chosen for this interview because of his extensive biophysics and medical physics research activities while he was employed by the University of California, Berkeley and San Francisco and at the Donner Laboratory. He discusses his involvement in wartime studies of effects of high altitude on aviators, carbon monoxide with radioactive tracers, blood studies with radioactive iron, human use committees, heavy-ion research with the Bevatron, boron isotope research, classified research involving human subjects, heavy-particle radiography, heavy- particle beams and medical research, and pituitary irradiation studies,.

NONE

1995-07-01T23:59:59.000Z

202

Literature Review of the Effects of Radiation and Temperature on the Aging of Concrete  

SciTech Connect

The open literature and accessible United States Department of Energy-sponsored reports were reviewed for the effects of radiation and temperature on concrete. No effects of radiation were found for exposures less than 1010 neutron/cm2 or 1010 Gy gamma for periods less than 50 years. Reductions in compressive and tensile strength and a marked increase in volume are reported for exposures greater than 1020 neutron/cm2 or 1010 rads of gamma. There are conflicting reports of damage for doses in the middle ranges.

D. L. Fillmore

2004-09-01T23:59:59.000Z

203

A Multicenter Phase II Study of Local Radiation Therapy for Stage IEA Mucosa-Associated Lymphoid Tissue Lymphomas: A Preliminary Report From the Japan Radiation Oncology Group (JAROG)  

Science Journals Connector (OSTI)

Purpose The aim of this study was to evaluate the efficacy and toxicity of moderate dose radiation therapy (RT) for mucosa-associated lymphoid tissue (MALT) lymphoma in a prospective multicenter phase II trial. Methods and Materials The subjects in this study were 37 patients with MALT lymphoma between April 2002 and November 2004. There were 16 male and 21 female patients, ranging in age from 24 to 82 years, with a median of 56 years. The primary tumor originated in the orbit in 24 patients, in the thyroid and salivary gland in 4 patients each, and 5 in the others. The median tumor dose was 30.6 Gy (range, 30.6–39.6 Gy), depending on the primary site and maximal tumor diameter. The median follow-up was 37.3 months. Results Complete remission (CR) or CR/unconfirmed was achieved in 34 patients (92%). The 3-year overall survival, progression-free survival, and local control probability were 100%, 91.9%, and 97.3%, respectively. Thirteen patients experienced Grade 1 acute toxicities including dermatitis, mucositis, and conjunctivitis. One patient developed Grade 2 taste loss. Regarding late toxicities, Grade 2 reactions including hypothyroidism, and radiation pneumonitis were observed in three patients, and Grade 3 cataract was seen in three patients. Conclusions This prospective phase II study demonstrated that moderate dose RT was highly effective in achieving local control with acceptable morbidity in 37 patients with MALT lymphoma.

Koichi Isobe; Yoshikazu Kagami; Keiko Higuchi; Takeshi Kodaira; Masatoshi Hasegawa; Naoto Shikama; Masanori Nakazawa; Ichiro Fukuda; Keiji Nihei; Kana Ito; Teruki Teshima; Yoshihiro Matsuno; Masahiko Oguchi

2007-01-01T23:59:59.000Z

204

Effect of solvents on the radiation-induced polymerization of ethyl and isopropyl vinyl ethers  

SciTech Connect

The effect of solvents on the radiation-induced cationic polymerization of ethyl and isopropyl vinyl ethers (EVE and IPVE, respectively) was investigated. EVE and IPVE polymerizations were carried out in bulk and in solution under superdry conditions in which polar impurities, especially water, have been reduced to negligible levels. This was accomplished by means of a sodium mirror technique using joint free baked out glass equipment and high vacuum. Plots of the monomer conversions and irradiation times were obtained for EVE and IPVE polymerizations in bulk and in benzene solution at constant monomer concentrations. The monomer concentration dependence of the polymerization rate was studied for EVE polymerization in bulk and in benzene, diethlyl ether, diglyme and methylene chloride, and for IPVE polymerization in bulk and in benzene. Solvent effect on the estimated propagating rate constants was examined for EVE and IPVE polymerization in bulk and in solution. The effect of temperature on the polymerization rate was also investigated for EVE polymerization in bulk ad in benzene, diethyl and diisopropyl ethers, methylene chloride and nitromethane, and for IPVE ploymerization in bulk and in benzene.

Hsieh, W.C.

1981-01-01T23:59:59.000Z

205

Effect of Solar Radiation on the Optical Properties and Molecular Composition of Laboratory Proxies of Atmospheric Brown Carbon  

E-Print Network (OSTI)

Effect of Solar Radiation on the Optical Properties and Molecular Composition of Laboratory Proxies A. Nizkorodov*, Department of Chemistry, University of California, Irvine, California 92697, United

Nizkorodov, Sergey

206

Low Dose Radiation Program: Radiation Biology and the Radiation Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Biology and the Radiation Research Program Biology and the Radiation Research Program The Department of Energy (DOE) and its predecessor organizations, Energy Research and Development Agency (ERDA) and Atomic Energy Commission (AEC), always have been concerned about the health effects of ionizing radiation. Extensive research has been conducted under their sponsorship at all levels of biological organization from molecules to man. Over the past 60 years, studies using every type of radiation source have included exposure to both external radiation sources and to internally deposited radioactive materials. These exposures used different dose patterns and distributions delivered over a wide range of experimental times. This extensive research provided the basis for the new Low Dose Radiation Research Program, linking

207

Effects of non-lethal doses of ionising radiation on the instrumental behaviour of rats  

Science Journals Connector (OSTI)

The dose-effect dependence of the instrumental behaviour of white rats after a single total ?-exposure (60Co) in the dosage range of 0.05 to 7.0 Gy was studied. Generalised results of seven years of our studies of post-radiation changes of operant behaviour in shuttle (active avoidance of shock â?? negative reinforcement) and in Skinner (drinking reward â?? positive reinforcement) boxes were evaluated weekly for a two-month period after exposure. The dose dependence, obtained using these two behavioural paradigms, displays a non-linear pattern. Three regions with different characteristic patterns of the observed effects were found: performance declines relative to control animals after exposure to doses up to 1.0 Gy; performance increases at doses in the range from 1.0 to 3.0 Gy; and again declines with dose increases up to 7.0 Gy. Possible underlying mechanisms, particularly the role of additional stress caused by animal testing, are discussed.

Eugene V. Tukalenko; Vyacheslav V. Varetsky; Olexander G. Rakochi; Inna R. Dmitrieva; Mikola U. Makarchuk

2007-01-01T23:59:59.000Z

208

ORIGINAL ARTICLE Effect of bismuth breast shielding on radiation  

E-Print Network (OSTI)

-effect transistors positioned in a customized anthropomorphic whole- body dosimetry verification phantom. Image noise. Funding: Supported by NIH Grants 1R01 HL109711-01 and 5KL2 RR024157, a Nuclear Cardiology Foundation American Society of Nuclear Cardiology. doi:10.1007/s12350-011-9473-x 100 #12;achievable (ALARA), while

Brenner, David Jonathan

209

LOW-LEVEL RADIATION HEALTH EFFECTS: PROGRAMS AND PANEL DISCUSSION  

E-Print Network (OSTI)

accident. The report of the Soviet Union to the International Atomic Energy Agency experts' meeting plutonium had been produced in reactors and separated for bomb production for -40 yr (Ref. 1. The reduction was presumably due to the reduced effects at low dose rate. THE DATA SETS In the former USSR

Shlyakhter, Ilya

210

How radiation and its effect were explained?: Scientific communication after the Fukushima Daiichi nuclear disaster  

Science Journals Connector (OSTI)

In this paper we examine eight popular books published immediately after the Fukushima Daiichi nuclear disaster. Our aim is to clarify the characteristics, problems in the scientific communication related to the health effects of radiation. The eight books are compared from the aspects of: 1) how units such as Bq, Gy and Sv are defined; 2) how the dose limits are explained; 3) how deterministic and stochastic effects of radiation are differentiated; 4) how LNT model is explained and evaluated; 5) how the fact that we evolved in the midst of natural background radiation is treated. The main finding of our survey is that although the authors of the examined texts start from the same 'scientific facts', in trying to make these facts easily understandable, they adopt different rhetorical strategies and eventually they end up delivering quite different and conflicting messages to the people.

Kazuhisa Todayama; Kaori Karasawa

2013-01-01T23:59:59.000Z

211

Quantitative evaluation of light scattering intensities of the crystalline lens for radiation related minimal change in interventional radiologists: a cross-sectional pilot study  

Science Journals Connector (OSTI)

......Medical Physics and Radiation Safety, Boston University...evaluate low-dose X-ray radiation effects on the eye by...hours and scattered radiation exposure during working...performed using commercial software (JMP 7.01J). Statistical......

Toshi Abe; Shigeru Furui; Hiroshi Sasaki; Yasuo Sakamoto; Shigeru Suzuki; Tatsuya Ishitake; Kinuyo Terasaki; Hiroshi Kohtake; Alexander M. Norbash; Richard H. Behrman; Naofumi Hayabuchi

2013-03-01T23:59:59.000Z

212

Re-examination of the Linear No Threshold (LNT) hypothesis, and a trial for the public to comprehend the reality of the low-dose effects of radiation  

Science Journals Connector (OSTI)

People have imprinted knowledge of the LNT hypothesis. Use of the terms LNT hypothesis, ALARA, or stochastic effect, etc. clouds the understanding of people about the real effects of very low doses of radiation. In this paper, the scientific basis of the LNT hypothesis is re-examined. A denial of the presence of a threshold means that individuals have no protection from even very small doses or dose rates of radiation in the body. As the human population is heterogeneous, a linear dose-response curve is obtained, as even whole majorities have a threshold. Current results from radiation epidemiological studies and experimental studies from cells and animals were reported by experts from USA, Canada and Japan at the Radition Effects Association (REA) symposium in March 2005 in Tokyo. The findings did not support the LNT hypothesis, but the importance of biological reactions and factors involving radiation-carcinogenesis. Even a few antinuclear audiences started to think about the presence of a body-defence mechanism against radiation. Necessary information on radiation-carcinogenesis is summarised in several figures for better comprehensions by the public.

Junko Matsubara

2006-01-01T23:59:59.000Z

213

Forbush decrease effects on radiation dose received on-board aeroplanes  

Science Journals Connector (OSTI)

......information provided by the US FAA to promote radiation safety for air carrier crew members. Radiat...Cosmic Radiation Humans Monte Carlo Method Radiation Dosage Radiation Monitoring methods Software Solar Activity...

P. Lantos

2005-12-01T23:59:59.000Z

214

AEROSOL DIRECT RADIATIVE EFFECTS OVER THE NORTHWEST ATLANTIC, NORTHWEST PACIFIC, AND NORTH INDIAN OCEANS  

E-Print Network (OSTI)

AEROSOL DIRECT RADIATIVE EFFECTS OVER THE NORTHWEST ATLANTIC, NORTHWEST PACIFIC, AND NORTH INDIAN, NORTHWEST PACIFIC, AND NORTH INDIAN OCEANS: ESTIMATES BASED ON IN-SITU CHEMICAL AND OPTICAL MEASUREMENTS, Y.24 , Tang, Y.25 , Weber, R. J.26 , and Wu, Y.27 1 NOAA/PMEL, 7600 Sand Point Way NE, Seattle, WA

215

Texture and porosity effects on the thermal radiative behavior of alumina ceramics.  

E-Print Network (OSTI)

1 Texture and porosity effects on the thermal radiative behavior of alumina ceramics. O. Rozenbaum1 for the comprehension of the ceramics thermal properties. Keywords: ceramics, texture, emissivity spectra, infrared (2009) 580-590" DOI : 10.1007/s10765-008-0510-1 #12;2 Abstract Thermal and optical properties

Paris-Sud XI, Université de

216

Comparison of low-energy radiation effects in polyethylene and cellulose Jussi Polvi, Kai Nordlund  

E-Print Network (OSTI)

Comparison of low-energy radiation effects in polyethylene and cellulose Jussi Polvi, Kai Nordlund, for a carbon atom in polyethylene chain, and for one of the carbon atoms in cellulose chain. Our analysis shows and on average slightly higher for the carbon atoms in the polyethylene chain than for the target carbon atom

Nordlund, Kai

217

Radiation effects on the surfaces of the Galilean satellites R. E. Johnson  

E-Print Network (OSTI)

20 Radiation effects on the surfaces of the Galilean satellites R. E. Johnson University and Johnson 1996). It can produce new species in the surface, it can produce and eject volatiles into the atmosphere, and it can be a source of the local plasma (Figure 20.1 and Johnson 1990, 1996, 1998

Johnson, Robert E.

218

Aerosol optical properties and their radiative effects in northern Zhanqing Li,1,2,3  

E-Print Network (OSTI)

and may also affect the hydrologic cycle. By scattering and absorbing solar radiative energy, aerosols regions. The East Asian Study of Tropospheric Aerosols: An International Regional Experiment (EAST-AIRE on climate over China. This study presents some preliminary results using continuous high-quality

Dickerson, Russell R.

219

THERMOHALINE INSTABILITIES INSIDE STARS: A SYNTHETIC STUDY INCLUDING EXTERNAL TURBULENCE AND RADIATIVE LEVITATION  

SciTech Connect

We have derived a new expression for the thermohaline mixing coefficient in stars, including the effects of radiative levitation and external turbulence, by solving Boussinesq equations in a nearly incompressible stratified fluid with a linear approximation. It is well known that radiative levitation of individual elements can lead to their accumulation in specific stellar layers. In some cases, it can induce important effects on the stellar structure. Here we confirm that this accumulation is moderated by thermohaline convection due to the resulting inverse {mu}-gradient. The new coefficient that we have derived shows that the effect of radiative accelerations on the thermohaline instability itself is small. This effect must however be checked in all computations. We also confirm that the presence of large horizontal turbulence can reduce or even suppress the thermohaline convection. These results are important as they concern all the cases of heavy element accumulation in stars. Computations of radiative diffusion must be revisited to include thermohaline convection and its consequences. It may be one of the basic reasons for the fact that the observed abundances are always smaller than those predicted by pure atomic diffusion. In any case, these processes have to compete with rotation-induced mixing, but this competition is more complex than previously thought due to their mutual interaction.

Vauclair, Sylvie; Theado, Sylvie, E-mail: sylvie.vauclair@irap.omp.eu [Universite de Toulouse, UPS-OMP and CNRS, Institut de Recherche en Astrophysique et Planetologie, 14 avenue Edouard Belin, F-31400 Toulouse (France)

2012-07-01T23:59:59.000Z

220

IAEACN69/EXP2/12 Highly Radiative Plasmas for Local Transport Studies and Power and Particle  

E-Print Network (OSTI)

tool for local transport studies, because the distribution of power loss between radiation. The response of the electron and ion temperatures to greatly increased radiative losses from the electrons alpha heating power must be dispersed. [1] Heat removal by radiation from controlled injection

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

IAEA-CN-69/EXP2/12 Highly Radiative Plasmas for Local Transport Studies and Power and Particle  

E-Print Network (OSTI)

for local transport studies, because the distribution of power loss between radiation and conduction plus. The response of the electron and ion temperatures to greatly increased radiative losses from the electrons alpha heating power must be dispersed.Ã?[1] Heat removal by radiation from controlled injection

222

Radiation exposure assessment for portsmouth naval shipyard health studies  

Science Journals Connector (OSTI)

......shipyards 226 0.49 Training 177 0.79 Industry...working near an operating submarine reactor...number of affected personnel and the low doses...worker safety and training programmes. Figure...individuals eligible for selection to nested case-control...P. Study of a selection of 10 historical......

R. D. Daniels; T. D. Taulbee; P. Chen

2004-09-01T23:59:59.000Z

223

NAS study on radiation takes the middle road  

Science Journals Connector (OSTI)

...giga-watt-year of nuclear generated electricity...These numbers make nuclear power seem attractive, but...the hazards posed by terrorism; that little is known...devel-oped a good fix on the risks ofa major nuclear plant leak. This study adopts...

E Marshall

1979-05-18T23:59:59.000Z

224

Radiation: Radiation Control (Indiana)  

Energy.gov (U.S. Department of Energy (DOE))

It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...

225

Radiation Damage Study in Natural Zircon Using Neutrons Irradiation  

SciTech Connect

Changes of atomic displacements in crystalline structure of natural zircon (ZrSiO{sub 4}) can be studied by using neutron irradiation on the surface of zircon and compared the data from XRD measurements before and after irradiation. The results of neutron irradiation on natural zircon using Pneumatic Transfer System (PTS) at PUSPATI TRIGA Research Reactor in the Malaysian Nuclear Agency are discussed in this work. The reactor produces maximum thermal power output of 1 MWatt and the neutron flux of up to 1x10{sup 13} ncm{sup -2}s{sup -1}. From serial decay processes of uranium and thorium radionuclides in zircon crystalline structure, the emission of alpha particles can produce damage in terms of atomic displacements in zircon. Hence, zircon has been extensively studied as a possible candidate for immobilization of fission products and actinides.

Lwin, Maung Tin Moe; Amin, Yusoff Mohd.; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Mohamed, Abdul Aziz [Materials Technology Group, Industrial Technology Division, Malaysian Nuclear Agency Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia); Karim, Julia Abdul [Reactor Physics Section, Nuclear Power Division, Malaysian Nuclear Agency Bangi, 43000 Kajang, Selangor Darul Ehsan (Malaysia)

2011-03-30T23:59:59.000Z

226

Experimental Studies on Coherent Synchrotron Radiation at an Emittance Exchange Beamline  

SciTech Connect

One of the goals of the Fermilab A0 photoinjector is to experimentally investigate the transverse to longitudinal emittance exchange (EEX) principle. Coherent synchrotron radiation in the emittance exchange line could limit the performance of the emittance exchanger at short bunch lengths. In this paper, we present experimental and simulation studies of the coherent synchrotron radiation (CSR) in the emittance exchange line at the A0 photoinjector. We report on time-resolved CSR studies using a skew-quadrupole technique. We also demonstrate the advantages of running the EEX with an energy chirped beam.

Thangaraj, J.C.T.; Thurman-Keup, R.; Ruan, J.; Johnson, A.S.; Lumpkin, A.H.; Santucci, J.; /Fermilab

2012-04-01T23:59:59.000Z

227

A Climatology of Surface Cloud Radiative Effects at the ARM Tropical Western Pacific Sites  

SciTech Connect

Cloud radiative effects on surface downwelling fluxes are investigated using long-term datasets from the three Atmospheric Radiation Measurement (ARM) sites in the Tropical Western Pacific (TWP) region. The Nauru and Darwin sites show significant variability in sky cover, downwelling radiative fluxes, and surface cloud radiative effect (CRE) due to El Niño and the Australian monsoon, respectively, while the Manus site shows little intra-seasonal or interannual variability. Cloud radar measurement of cloud base and top heights are used to define cloud types so that the effect of cloud type on the surface CRE can be examined. Clouds with low bases contribute 71-75% of the surface shortwave (SW) CRE and 66-74% of the surface longwave (LW) CRE at the three TWP sites, while clouds with mid-level bases contribute 8-9% of the SW CRE and 12-14% of the LW CRE, and clouds with high bases contribute 16-19% of the SW CRE and 15-21% of the LW CRE.

McFarlane, Sally A.; Long, Charles N.; Flaherty, Julia E.

2013-04-01T23:59:59.000Z

228

Revisiting a pre-inflationary radiation era and its effect on the CMB power spectrum  

E-Print Network (OSTI)

We revisit the scenario where inflation is preceded by a radiation era by considering that the inflaton too could have been in thermal equilibrium early in the radiation era. Hence we take into account not only the effect of a pre-inflationary era on the inflaton mode functions but also that of a frozen thermal distribution of inflaton quanta. We initially discuss in detail the issues relevant to our scenario of a pre-inflationary radiation dominated era and then obtain the scalar power spectrum for this scenario. We find that the power spectrum is free from infrared divergences. We then use the WMAP and Planck data to determine the constraints on the inflaton comoving `temperature' and on the duration of inflation. We find that the best fit value of the duration of inflation is less than 1 e-folding more than what is required to solve cosmological problems, while only an upper bound on the inflaton temperature can be obtained.

Das, Suratna; Prasad, Jayanti; Rangarajan, Raghavan

2014-01-01T23:59:59.000Z

229

Effect of electric field on heat transfer performance of automobile radiator at low frontal air velocity  

Science Journals Connector (OSTI)

The effect of electric field on the performance of automobile radiator is investigated in this work. In this experiment, a louvered fin and flat tube automobile radiator was mounted in a wind tunnel and there was heat exchange between a hot water stream circulating inside the tube and a cold air stream flowing through the external surface. The electric field was supplied on the airside of the heat exchanger and its supply voltage was adjusted from 0 kV to 12 kV. From the experiment, it was found that the unit with electric field pronounced better heat transfer rate, especially at low frontal velocity of air. The correlations for predicting the air-side heat transfer coefficient of the automobile radiator, with and without electric field, at low frontal air velocity were also developed and the predicted results agreed very well with the experimental data.

S. Vithayasai; T. Kiatsiriroat; A. Nuntaphan

2006-01-01T23:59:59.000Z

230

Biological effects of radiation from dental radiography. Council on Dental Materials, Instruments, and Equipment  

SciTech Connect

Clearly, there is ample evidence of adverse effects of radiation in sufficient doses. There is at present no proof of such effects from doses commonly employed in dental practice; however, it has not been possible to prove the absence of such effects. Most experts now agree that there may be a small, difficult to quantify risk of cancer or genetic mutation from diagnostic exposure in patients and in personnel exposed during work. Prudence dictates acceptance of this position until proof to the contrary is available. This report has presented recent attempts to quantify the risk to patients based on speculative calculations and extrapolations. Indices of population risks indicate that medical radiology is the largest source of human-made genetic and leukemogenic radiation burden to the American public. Dental radiology contributes a small-but not necessarily insignificant-portion. Of major concern is the increasing use of radiation for diagnostic purposes in both medicine and dentistry. Technological advances have reduced exposure per examination; presumably this trend will continue so that total exposure of populations to radiation in the healing arts will not increase. Recent analyses suggest that the cancer risk to a patient from a dental radiographic examination is of the order of one in a million; the genetic risk is substantially less, about one in a billion. The risks appear to be essentially equal for full-mouth intraoral and for panoramic examinations. These estimates are numerically quite small, but the effects are severe. Thus, these risks cannot be ignored. However, we currently accept risks of similar magnitude in our daily lives (Table 9)50,51 In addition, the risk of failure to make an accurate diagnosis may be greater than the risk from exposure to the radiation from a justified and properly conducted radiographic examination.

Gibbs, S.J.

1982-08-01T23:59:59.000Z

231

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation Deok-Jin Jang 1 , Mingquan Guo 1 , Julia S.F.Chu 2 , Kyle T. Kurpinski 2 , Bjorn Rydberg 1 , Song Li 2 , and Daojing Wang 1 1. Life Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720 2. Department of Bioengineering, University of California, Berkeley, CA 94720 We will present data obtained during the first year of our DOE/NASA Low Dose Radiation Research program. We utilized a comprehensive approach including transcriptomics, proteomics, phosphoproteomics, and biochemistry to characterize human mesenchymal stem cells (MSCs) in response to low dose ionizing radiation. We first determined the cell survival, proliferation, and osteogenic differentiation of

232

Appendix G. Radiation Appendix G. Radiation  

E-Print Network (OSTI)

-made sources. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation of radiation and its effects on the environment and biological systems. Radiation comes from natural and humanAppendix G. Radiation #12;#12;Appendix G. Radiation This appendix presents basic facts about

Pennycook, Steve

233

Three-dimensional CFD analysis for simulating the greenhouse effect in solar chimney power plants using a two-band radiation model  

Science Journals Connector (OSTI)

Abstract The greenhouse effect in the solar collector has a fundamental role to produce the upward buoyancy force in solar chimney power plant systems. This study underlines the importance of the greenhouse effect on the buoyancy-driven flow and heat transfer characteristics through the system. For this purpose, a three-dimensional unsteady model with the RNG k–? turbulence closure was developed, using computational fluid dynamics techniques. In this model, to solve the radiative transfer equation the discrete ordinates (DO) radiation model was implemented, using a two-band radiation model. To simulate radiation effects from the sun's rays, the solar ray tracing algorithm was coupled to the calculation via a source term in the energy equation. Simulations were carried out for a system with the geometry parameters of the Manzanares power plant. The effects of the solar insolation and pressure drop across the turbine on the flow and heat transfer of the system were considered. Based on the numerical results, temperature profile of the ground surface, thermal collector efficiency and power output were calculated and the results were validated by comparing with experimental data of this prototype power plant. Furthermore, enthalpy rise through the collector and energy loss from the chimney outlet between 1-band and two-band radiation model were compared. The analysis showed that simulating the greenhouse effect has an important role to accurately predict the characteristics of the flow and heat transfer in solar chimney power plant systems.

Ehsan Gholamalizadeh; Man-Hoe Kim

2014-01-01T23:59:59.000Z

234

Radiation effects on the electrical properties of hafnium oxide based MOS capacitors.  

SciTech Connect

Hafnium oxide-based MOS capacitors were investigated to determine electrical property response to radiation environments. In situ capacitance versus voltage measurements were analyzed to identify voltage shifting as a result of changes to trapped charge with increasing dose of gamma, neutron, and ion radiation. In situ measurements required investigation and optimization of capacitor fabrication to include dicing, cleaning, metalization, packaging, and wire bonding. A top metal contact of 200 angstroms of titanium followed by 2800 angstroms of gold allowed for repeatable wire bonding and proper electrical response. Gamma and ion irradiations of atomic layer deposited hafnium oxide on silicon devices both resulted in a midgap voltage shift of no more than 0.2 V toward less positive voltages. This shift indicates recombination of radiation induced positive charge with negative trapped charge in the bulk oxide. Silicon ion irradiation caused interface effects in addition to oxide trap effects that resulted in a flatband voltage shift of approximately 0.6 V also toward less positive voltages. Additionally, no bias dependent voltage shifts with gamma irradiation and strong oxide capacitance room temperature annealing after ion irradiation was observed. These characteristics, in addition to the small voltage shifts observed, demonstrate the radiation hardness of hafnium oxide and its applicability for use in space systems.

Petrosky, J. C. (Air Force Institute of Technology, Wright-Patterson Air Force Base, OH); McClory, J. W. (Air Force Institute of Technology, Wright-Patterson Air Force Base, OH); Bielejec, Edward Salvador; Foster, J. C. (Air Force Institute of Technology, Wright-Patterson Air Force Base, OH)

2010-10-01T23:59:59.000Z

235

Effects of oxygen concentration on radiative loss from normal-gravity and microgravity methane diffusion flames  

SciTech Connect

Laminar diffusion flames of methane, burning in quiescent oxidizing environments at atmospheric pressure, have been studied under both normal-gravity and microgravity conditions. Radiation from these flames is measured using a wide-view-angle, thermopile detector radiometer. The oxidizer was 18, 21, and 30 percent oxygen in nitrogen. 17 refs.

Bahadori, M.Y.; Edelman, R.B.; Stocker, D.P.; Sotos, R.G.; Vaughan, D.F. (Science Applications International Corp., Torrance, CA (United States) Rockwell International Corp., Rocketdyne Div., Canoga Park, CA (United States) NASA, Lewis Research Center, Cleveland, OH (United States))

1992-01-01T23:59:59.000Z

236

Ionizing Radiation as an Initiator: Effects of Proliferation and Promotion Time on Tumor Incidence in Mice  

Science Journals Connector (OSTI)

...portion of the dose-response curve these two doses reside, we cannot accu rately say that the...cell carcinomas did not appear to depend on dose. A wider range of doses of ionizing radiation needs to be studied. A representative basal...

Deborah Jaffe and G. Tim Bowden

1987-12-15T23:59:59.000Z

237

Dose reconstruction for the Urals population. Joint Coordinating Committee on Radiation Effects Research, Project 1.1 -- Final report  

SciTech Connect

This work is being carried out as a feasibility study to determine if a long-term course of work can be implemented to assess the long-term risks of radiation exposure delivered at low to moderate dose rates to the populations living in the vicinity of the Mayak Industrial Association (MIA). This work was authorized and conducted under the auspices of the US-Russian Joint Coordinating Committee on Radiation Effects Research (JCCRER) and its Executive Committee (EC). The MIA was the first Russian site for the production and separation of plutonium. This plant began operation in 1948, and during its early days there were technological failures that resulted in the release of large amounts of waste into the rather small Techa River. There were also gaseous releases of radioiodines and other radionuclides during the early days of operation. In addition, there was an accidental explosion in a waste storage tank in 1957 that resulted in a significant release. The Techa River Cohort has been studied for several years by scientists from the Urals Research Centre for Radiation Medicine and an increase in both leukemia and solid tumors has been noted.

Degteva, M.O. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation)] [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation); Drozhko, E. [Branch 1 of Moscow Biophysics Inst., Ozersk (Russian Federation)] [Branch 1 of Moscow Biophysics Inst., Ozersk (Russian Federation); Anspaugh, L.R. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); Napier, B.A. [Pacific Northwest National Lab., Richland, WA (United States)] [Pacific Northwest National Lab., Richland, WA (United States); Bouville, A.C. [National Cancer Inst., Bethesda, MD (United States)] [National Cancer Inst., Bethesda, MD (United States); Miller, C.W. [Centers for Disease Control and Prevention, Atlanta, GA (United States)] [Centers for Disease Control and Prevention, Atlanta, GA (United States)

1996-02-01T23:59:59.000Z

238

Theoretical study of gas heated in a porous material subjected to a concentrated solar radiation (*)  

E-Print Network (OSTI)

W solar furnace of Solar Energy Laboratory in Odeillo (France). Revue Phys. Appl. 15 (1980) 423-426 MARS423 Theoretical study of gas heated in a porous material subjected to a concentrated solar exposed to the solar radiation. These quantities may be expressed in any set consistent units. 1

Paris-Sud XI, Université de

239

Solar radiation management impacts on agriculture in China: A case study in the Geoengineering  

E-Print Network (OSTI)

Solar radiation management impacts on agriculture in China: A case study in the Geoengineering, Environment Canada, Toronto, Ontario, Canada, 3 School of Earth and Ocean Sciences, University of Victoria, Victoria, British Columbia, Canada, 4 State Key Laboratory of Earth Surface Processes and Resource Ecology

Robock, Alan

240

Low-energy x-ray dosimetry studies (7 to 17.5 keV) with synchroton radiation  

SciTech Connect

Unique properties of synchrotron radiation (SR), such as its high intensity, brightness, polarization, and broad spectral distribution (extending from x-ray to infra-red wavelengths) make it an attractive light source for numerous experiments. As SR facilities are rapidly being built all over the world, they introduce the need for low-energy x-ray dosemeters because of the potential radiation exposure to experimenters. However, they also provide a unique opportunity for low-energy x-ray dosimetry studies because of the availability of monochromatic x-ray beams. Results of such studies performed at the Stanford Synchrotron Radiation Laboratory are described. Lithium fluoride TLDs (TLD-100) of varying thicknesses (0.015 to 0.08 cm) were exposed free in air to monochromatic x-rays (7 to 17.5 keV). These exposures were monitored with ionization chambers. The response (nC/Gy) was found to increase with increasing TLD thickness and with increasing beam energy. A steeper increase in response with increasing energy was observed with the thicker TLDs. The responses at 7 and 17.5 keV were within a factor of 2.3 and 5.2 for the 0.015 and 0.08 cm-thick TLDs, respectively. The effects of narrow (beam size smaller than the dosemeter) and broad (beam size larger than the dosemeter) beams on the response of the TLDs are also reported.

Ipe, N.E.; Bellamy, H.; Flood, J.R. [and others

1995-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Experimental Study of Coherent Synchrotron Radiation in the Emittance Exchange Line at the A0-Photoinjector  

SciTech Connect

Next generation accelerators will require a high current, low emittance beam with a low energy spread. Such accelerators will employ advanced beam conditioning systems such as emittance exchangers to manipulate high brightness beams. One of the goals of the Fermilab A0 photoinjector is to investigate the transverse to longitudinal emittance exchange principle. Coherent synchrotron radiation could limit high current operation of the emittance exchanger. In this paper, we report on the preliminary experimental and simulation study of the coherent synchroton radiation (CSR) in the emittance exchange line at the A0 photoinjector.

Thangaraj, Jayakar C. T.; Thurman-Keup, R.; Johnson, A.; Lumpkin, A. H.; Edwards, H.; Ruan, J.; Santucci, J.; Sun, Y. E.; Church, M. [Fermi National Accelerator Labaratory, Batavia, IL, 60510 (United States); Piot, P. [Fermi National Accelerator Labaratory, Batavia, IL, 60510 (United States); Department of Physics, DeKalb, IL, 60115 (United States)

2010-11-04T23:59:59.000Z

242

Flavopiridol Potentiates the Cytotoxic Effects of Radiation in Radioresistant Tumor Cells in Which p53 is Mutated or Bcl-2 is Overexpressed  

SciTech Connect

Purpose: Loss of the cell-cycle regulatory protein p53 or overexpression of the antiapoptotic protein Bcl-2 is associated with resistance to radiation in several types of cancer cells. Flavopiridol, a synthetic flavone, inhibits the growth of malignant tumors cells in vitro and in vivo through multiple mechanisms. The purpose of the present study is to clarify whether flavopiridol enhances the cytotoxic effects of radiation in tumor cells that contain dysfunction p53 or that overexpress Bcl-2. Methods and Materials: A human glioma cell line (A172/mp53) stably transfected with a plasmid containing mutated p53 and a human cervical cancer cell line (HeLa/bcl-2) transfected with a bcl-2 expression plasmid were used. Cells were incubated with flavopiridol for 24 h after radiation, and then cell viability was determined by a colony formation assay. Foci of phosphorylated histone H2AX were also evaluated as a sensitive indicator of DNA double-strand breaks. Results: Compared with the parental wild-type cells, both transfected cell lines were more resistant to radiation. Post-treatment with flavopiridol increased the cytotoxic effects of radiation in both transfected cell lines, but not in their parental wild-type cell lines. Post-treatment with flavopiridol inhibited sublethal damage repair as well as the repair of DNA double-strand breaks in response to radiation. Conclusions: Flavopiridol enhanced the cytotoxic effect of radiation in radioresistant tumor cells that harbor p53 dysfunction or Bcl-2 overexpression. A combination treatment of flavopiridol with radiation has the potential to conquer the radioresistance of malignant tumors induced by the genetic alteration of p53 or bcl-2.

Hara, Takamitsu [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama (Japan); Omura-Minamisawa, Motoko [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama (Japan)], E-mail: momuram@med.yokohama-cu.ac.jp; Kang, Yun; Cheng, Chao; Inoue, Tomio [Department of Radiology, Yokohama City University Graduate School of Medicine, Yokohama (Japan)

2008-08-01T23:59:59.000Z

243

Computational study of atmospheric transfer radiation on an equatorial tropical desert (La Tatacoa, Colombia)  

E-Print Network (OSTI)

Radiative transfer models explain and predict interaction between solar radiation and the different elements present in the atmosphere, which are responsible for energy attenuation. In Colombia there have been neither measurements nor studies of atmospheric components such as gases and aerosols that can cause turbidity and pollution. Therefore satellite images cannot be corrected radiometrically in a proper way. When a suitable atmospheric correction is carried out, loss of information is avoided, which may be useful for discriminating image land cover. In this work a computational model was used to find radiative atmospheric attenuation (300 1000nm wavelength region) on an equatorial tropical desert (La Tatacoa, Colombia) in order to conduct an adequate atmospheric correction.

Delgado-Correal, Camilo; Castaño, Gabriel

2012-01-01T23:59:59.000Z

244

The effects of atomic oxygen on the thermal emittance of high temperature radiator surfaces  

SciTech Connect

Radiator surfaces on high temperature space power systems such as the SP-100 space nuclear power system must maintain a high emittance level in order to reject waste heat effectively. one of the primary materials under consideration for the radiators is carbon-carbon composite. Since carbon is susceptible to attack by atomic oxygen in the low Earth orbital environment, it is important to determine the durability of carbon composites in this environment as well as the effect atomic oxygen has on the thermal emittance of the surface if it is to be considered for use as a radiator. Results indicate that the thermal emittance of carbon-carbon composite (as low as 0.42) can be enhanced by exposure to a directed beam of atomic oxygen to levels above 0.85 at 800 K. This emittance enhancement is due to a change in the surface morphology as a result of oxidation. High aspect ratio cones are formed on the surface which allow more efficient trapping of incident radiation. Erosion of the surface due to oxidation is similar to that for carbon; so that at altitudes less than {approximately}600 km, thickness loss of the radiator could be significant (as much as 0.1 cm/year). A protective coating or oxidation barrier forming additive may be needed to prevent atomic oxygen attack after the initial high emittance surface is formed. Textured surfaces can be formed in ground based facilities or possibly in space if emittance is not sensitive to the orientation of the atomic oxygen arrival that forms the texture.

Rutledge, S.K. [Lewis Research Center, Cleveland, OH (United States); Hotes, D.L.; Paulsen, P.E. [Cleveland State Univ., OH (United States)

1994-09-01T23:59:59.000Z

245

Assessment of Fukushima-Derived Radiation Doses and Effects on Wildlife in Japan  

Science Journals Connector (OSTI)

Following releases from the nuclear accident at the Fukushima-Daiichi Nuclear Power Station (FDNPS), contention has arisen over the potential radiological impact on wildlife. ... This work was conducted under the auspices of the UNSCEAR, and a more comprehensive version of the assessment presented here is reported within the UN publication “Levels and effects of radiation exposure due to the nuclear accident after the 2011 Great East Japan earthquake and Tsunami”. ...

P. Strand; T. Aono; J. E. Brown; J. Garnier-Laplace; A. Hosseini; T. Sazykina; F. Steenhuisen; J. Vives i Batlle

2014-02-14T23:59:59.000Z

246

Synthetic Lorentz force in classical atomic gases via Doppler effect and radiation pressure  

E-Print Network (OSTI)

We theoretically predict a novel type of synthetic Lorentz force for classical (cold) atomic gases, which is based on the Doppler effect and radiation pressure. A fairly uniform and strong force can be constructed for gases in macroscopic volumes of several cubic millimeters and more. This opens the possibility to mimic classical charged gases in magnetic fields, such as those in a tokamak, in cold atom experiments.

Dub?ek, T; Juki?, D; Aumiler, D; Ban, T; Buljan, H

2014-01-01T23:59:59.000Z

247

Effect of sun radiation on the thermal behavior of distribution transformer  

Science Journals Connector (OSTI)

Performance and life of oil-immersed distribution transformers are strongly dependent on the oil temperature. Transformers, working in regions with high temperature and high solar radiation, usually suffer from excessive heat in summers which results in their early failures. In this paper, the effect of sun radiation on the transformer was investigated by using experimental and analytical methods. Transformer oil temperature was measured in two different modes, with and without sun shield. Effects of different parameters such as direct and indirect solar radiation on the thermal behavior of the transformer were mathematically modeled and the results were compared with experimental findings. Agreements between the experimental and numerical results show that the model can reasonably predict thermal behavior of the transformer. It was found that a sun shield has an important effect on the oil temperature reduction in summer which could be as high as 7 °C depending on the load ratio. The amount of temperature reduction by sun shield reduces as the load ratio of transformer increases. By installing a sun shield and reducing oil temperature, transformer life could be increased up to 24% in average.

Ebrahim Hajidavalloo; Mohamad Mohamadianfard

2010-01-01T23:59:59.000Z

248

Radiative effects of the smoke clouds from the Kuwait oil fires  

SciTech Connect

The radiative effects of the smoke from the Kuwait oil fires were assessed by measuring downwelling and upwelling solar flux, as well as spectral solar extinction beneath, above, and within the smoke plume. Seven radiation flight missions were undertaken between May 16 and June 2, 1991, to characterize the plume between the source region in Kuwait and approximately 200 km south, near Manama, Bahrain. The authors present results from one flight representative of conditions of the composite plume. On May 18, 1991, in a homogeneous, well-mixed region of smoke approximately 100 km downstream of the fires, visible optical depths as high as 2 were measured, at which time transmission to the surface was 8%, while 78% of the solar radiation was absorbed by the smoke. The calculated instantaneous heating rate inside the plume reached 24 K/d. While these effects are probably typical of those regions in the Persian Gulf area directly covered by the smoke, there is no evidence to suggest significant climatic effects in other regions. 13 refs., 3 figs., 1 tab.

Pilewskie, P.; Valero, F.P.J. [NASA/Ames Research Center, Moffett Field, CA (United States)

1992-09-20T23:59:59.000Z

249

Vibration and acoustic radiation from inhomogeneous structures: Effect of motion of forcing function  

Science Journals Connector (OSTI)

Homogeneous structures are known to radiate only for supersonic structural wavenumbers. The presence of inhomogeneities such as boundaries discrete stiffeners and variable stiffness has been shown to introduce additional modes that will radiate if the structural wavenumbers are supersonic. The radiation pattern for an infinite plate with evenly spaced stiffness gives rise to a stop?passband spectrum. The plate with a continuously varying stiffness also gives rise to similar conditions. All of the previous analyses have always considered stationary forcing functions. In this paper the analyses for the fixed forcing function will be reviewed and then they will be generalized to the case of the forcing function moving along the plate at speeds up to and greater than the wave speeds in the solid. The results presented will show that for certain values of the frequency rib spacings and forcing function velocity traveling wave modes may change direction decaying modes may become traveling modes and modes may change from subsonic to supersonic and vice versa depending upon the relative motion of the forcing function. The effect of the motion may thus enhance or reduce the acoustic radiation.

Mauro Pierucci

1988-01-01T23:59:59.000Z

250

Can the Infrared Radiation that Causes the Enhanced Greenhouse Effect Be Put to Better Use?  

Science Journals Connector (OSTI)

Increasing levels of certain greenhouse gases (GHGs) most importantly CO 2 in the earths atmosphere lead to climate change and global warming as a result of these gases interacting with thermal infrared (TIR) radiation from earth to space. Here the option of modifying this radiation is analyzed which would result in modified TIR radiation that would interact less with atmospheric CO 2 . This alleviates the enhanced greenhouse effect and at the same time would allow for energy recovery as heat and/or power. Power production is of course limited by thermodynamics Second Law. It is shown that various options exist for TIR radiation modification which may be used to generate temperature gradients or temperature differences between volumes of (gases containing) CO 2 of sufficient optical thickness. This may be further exploited for power generation: a first simple case shows power generation of ?1? W ? per ? m 2 surface at a Carnot efficiency of ?7% using the sky and ground level surroundings as heat reservoirs.

Ron Zevenhoven

2008-01-01T23:59:59.000Z

251

An Assessment of the Current US Radiation Oncology Workforce: Methodology and Global Results of the American Society for Radiation Oncology 2012 Workforce Study  

SciTech Connect

Purpose: To determine the characteristics, needs, and concerns of the current radiation oncology workforce, evaluate best practices and opportunities for improving quality and safety, and assess what we can predict about the future workforce. Methods and Materials: An online survey was distributed to 35,204 respondents from all segments of the radiation oncology workforce, including radiation oncologists, residents, medical dosimetrists, radiation therapists, medical physicists, nurse practitioners, nurses, physician assistants, and practice managers/administrators. The survey was disseminated by the American Society for Radiation Oncology (ASTRO) together with specialty societies representing other workforce segments. An overview of the methods and global results is presented in this paper. Results: A total of 6765 completed surveys were received, a response rate of 19%, and the final analysis included 5257 respondents. Three-quarters of the radiation oncologists, residents, and physicists who responded were male, in contrast to the other segments in which two-thirds or more were female. The majority of respondents (58%) indicated they were hospital-based, whereas 40% practiced in a free-standing/satellite clinic and 2% in another setting. Among the practices represented in the survey, 21.5% were academic, 25.2% were hospital, and 53.3% were private. A perceived oversupply of professionals relative to demand was reported by the physicist, dosimetrist, and radiation therapist segments. An undersupply was perceived by physician's assistants, nurse practitioners, and nurses. The supply of radiation oncologists and residents was considered balanced. Conclusions: This survey was unique as it attempted to comprehensively assess the radiation oncology workforce by directly surveying each segment. The results suggest there is potential to improve the diversity of the workforce and optimize the supply of the workforce segments. The survey also provides a benchmark for future studies, as many changes in the healthcare field exert pressure on the workforce.

Vichare, Anushree; Washington, Raynard; Patton, Caroline; Arnone, Anna [ASTRO, Fairfax, Virginia (United States); Olsen, Christine [Massachusetts General Hospital, Boston, Massachusetts, (United States); Fung, Claire Y. [Commonwealth Newburyport Cancer Center, Newburyport, Massachusetts (United States); Hopkins, Shane [William R. Bliss Cancer Center, Ames, Iowa (United States); Pohar, Surjeet, E-mail: spohar@netzero.net [Indiana University Health Cancer Center East, Indiana University, Indianapolis, Indiana (United States)

2013-12-01T23:59:59.000Z

252

Dynamic Effects on the Tropical Cloud Radiative Forcing and Radiation Budget JIAN YUAN, DENNIS L. HARTMANN, AND ROBERT WOOD  

E-Print Network (OSTI)

in the tropics, using the methodology suggested by Bony et al. Cloud and radiation budget quantities source of uncertainty in pre- dicting future climate (Cess et al. 2001b; Stephens 2005; Solomon et al

Wood, Robert

253

The similar effects of low-dose ionizing radiation and non-ionizing radiation from background environmental levels of exposure  

Science Journals Connector (OSTI)

The meltdown and release of radioactivity (ionizing radiation) from four damaged nuclear reactors at the Fukushima Nuclear Facility in Japan in March 2011 continues to contaminate air and ocean water even 1 year ...

Cindy Sage

2012-06-01T23:59:59.000Z

254

Studies on Induced Variation in the Rhizobia: II. Radiation Sensitivity and Induction of Antibiotic-resistance Markers  

Science Journals Connector (OSTI)

...0.I 0 1 2 DOSE (ergs/mm2...quantitative estimations, as in the...DISCUSSION Radiation dose-survival...an ionizing radiation, i.e...more accurate estimation of mutation...ergs/mm2XIO3 DOSE FIG. 3. Effect...

E. A. Schwinghamer; R. L. Dalmas

1961-09-01T23:59:59.000Z

255

Public meetings on radiation and its health effects caused by the Fukushima nuclear accident  

SciTech Connect

The Japan Atomic Energy Agency (JAEA) has held public meetings on radiation and its health effects mainly for parents of students in kindergartens, elementary schools, and junior high schools in Fukushima and Ibaraki prefectures after the Fukushima nuclear accident. These meetings are held based on our experience of practicing risk communication activities for a decade in JAEA with local residents. By analyzing questionnaires collected after the meetings, we confirmed that interactive communication is effective in increasing participants' understanding and in decreasing their anxiety. Most of the participants answered that they understood the contents and that it eased their mind. (authors)

Sugiyama, K.; Ayame, J.; Takashita, H.; Yamamoto, R. [Risk Communication Study Office Japan Atomic Energy Agency 4-33 Muramatsu, Tokai-mura, IBARAKI, 319-1194 (Japan)

2013-07-01T23:59:59.000Z

256

Reduced Kilovoltage in Computed Tomography–Guided Intervention in a Community Hospital: Effect on the Radiation Dose  

Science Journals Connector (OSTI)

AbstractPurpose The purpose of this study was to determine whether low-kilovoltage (80 or 100 kV) computed tomography (CT)-guided interventions performed in a community-based hospital are feasible and to compare radiation exposure incurred with conventional 120 kV potential. Materials and Methods Effective doses (ED) received by patients who underwent CT-guided intervention were analysed before and after a low-dose kilovoltage protocol was instituted in our department. We performed CT-guided procedures of 93 consecutive patients by using conventional 120-kV tube voltage (50 patients) and a low voltage of 80 or 100 kV for the remainder of this cohort. Automatic tube current modulation was enabled to obtain the best image quality. Procedure details were prospectively recorded and included examination site and type, slice width, tube voltage and current, dose length product, volume CT dose index, and size-specific dose estimate. Dose length product was converted to ED to account for radiosensitivity of specific organs. Statistical comparisons with test differences in the ED, volume CT dose index, size-specific dose estimate, and effective diameter (patient size) were made by using the Student t test. Results All but 6 of the procedures performed at 80 kV were successful, for a success rate of 86%. At lower voltages, the ED was significantly (P dose radiation technique by using 80 or 100 kV results in a high technical success rate for pelvic, chest, and abdomen CT-guided interventional procedures, although dramatically decreasing radiation exposure. There was no significant difference in effective diameter (patient size) between the conventional and the low-dose groups, which would suggest that dose reduction was indeed a result of kVp change and not patient size.

Saman Rezazadeh; Steven J. Co; Simon Bicknell

2014-01-01T23:59:59.000Z

257

Radiation Probabilities, Auger Effect and Energy Level Widths for Au(79)  

Science Journals Connector (OSTI)

The theory of energy level widths developed by Weisskopf and Wigner and by Wentzel is applied to the calculation of the energy level widths of Au(79). Radiation and Auger transition probabilities are determined separately with the aid of numerically integrated nonrelativistic eigenfunctions, the latter being calculated for electrons moving in the Fermi-Thomas field of Tl(81)++. Sources of error are considered, the major one being the nonrelativistic treatment. The band width due to the interaction of electrons in different atoms in the crystal lattice does not add materially to the level width of the OI and lower states. Except for the K state, the Auger contribution to the width exceeds that of the radiation transitions. Where the majority of the significant Auger effects have been calculated (LI,MI,NI) the total calculated width is found to be appreciably in excess of the observed width, but of the same order. The results confirm the view that the contributions of radiation transitions and Auger effects to the level widths of the initial and final states of the atom suffice to explain the magnitude of the widths of the x-ray lines emitted by the heavy elements.

E. G. Ramberg and F. K. Richtmyer

1937-06-01T23:59:59.000Z

258

Differences in Brainstem Fiber Tract Response to Radiation: A Longitudinal Diffusion Tensor Imaging Study  

SciTech Connect

Purpose: To determine whether radiation-induced changes in white matter tracts are uniform across the brainstem. Methods and Materials: We analyzed serial diffusion tensor imaging data, acquired before radiation therapy and over 48 to 72 months of follow-up, from 42 pediatric patients (age 6-20 years) with medulloblastoma. FSL software (FMRIB, Oxford, UK) was used to calculate fractional anisotropy (FA) and axial, radial, and mean diffusivities. For a consistent identification of volumes of interest (VOIs), the parametric maps of each patient were transformed to a standard brain space (MNI152), on which we identified VOIs including corticospinal tract (CST), medial lemniscus (ML), transverse pontine fiber (TPF), and middle cerebellar peduncle (MCP) at the level of pons. Temporal changes of DTI parameters in VOIs were compared using a linear mixed effect model. Results: Radiation-induced white matter injury was marked by a decline in FA after treatment. The decline was often accompanied by decreased axial diffusivity, increased radial diffusivity, or both. This implied axonal damage and demyelination. We observed that the magnitude of the changes was not always uniform across substructures of the brainstem. Specifically, the changes in DTI parameters for TPF were more pronounced than in other regions (P<.001 for FA) despite similarities in the distribution of dose. We did not find a significant difference among CST, ML, and MCP in these patients (P>.093 for all parameters). Conclusions: Changes in the structural integrity of white matter tracts, assessed by DTI, were not uniform across the brainstem after radiation therapy. These results support a role for tract-based assessment in radiation treatment planning and determination of brainstem tolerance.

Uh, Jinsoo, E-mail: jinsoo.uh@stjude.org [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Li, Yimei; Feng, Tianshu [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Gajjar, Amar [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Ogg, Robert J.; Hua, Chiaho [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)] [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee (United States)

2013-06-01T23:59:59.000Z

259

"Nuclear Lighthouse Effect"Studies Win BESSY Prize  

NLE Websites -- All DOE Office Websites (Extended Search)

9th, 2003 9th, 2003 "Nuclear Lighthouse Effect" Studies Win BESSY Prize A new technique for high-resolution x-ray scattering spectroscopy developed at the Advanced Photon Source has garnered an award for innovation in synchrotron radiation research. Ralf Röhlsberger, Professor of Physics at the Technische Universitaet Muenchen, is a recipient of the "Innovationspreis Synchrotronstrahlung 2002" ("Innovation Prize in Synchrotron Radiation 2002") prize awarded annually by the Friends of BESSY. The award, which honors "new developments in the field that provide access to and use of synchrotron radiation," was presented for Röhlsberger's "groundbreaking work in the nuclear resonant scattering of synchrotron radiation," the so-called "Nuclear Lighthouse Effect," a method

260

Record of the first meeting of the Joint Coordinating Committee for Radiation Effects Research  

SciTech Connect

This conference was held July 27--28, 1994 in Moscow. The main purpose of the meeting was to implement an agreement between the Russian Federation and the US to facilitate cooperative research on health and environmental effects of radiation. It was hoped that the exchange of information would provide a good basis for employing new scientific knowledge to implement practical measures to facilitate the rehabilitation of radioactively contaminated areas and to treat radiation illnesses. The Russian Federation suggested five main scientific areas for cooperative research. They will prepare proposals on 4--5 projects within the scope of the scientific areas discussed and forward them to the US delegation for consideration of the possibility to facilitate joint research.

NONE

1994-12-31T23:59:59.000Z

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261

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

SciTech Connect

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

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

2014-05-15T23:59:59.000Z

262

New data on the effect of solar radiation and ?-farnesene on development of apple superficial scald during storage  

Science Journals Connector (OSTI)

The previously unknown selective effect of solar radiation on the development of apple superficial scald is established. Superficial scald doesn’t occur on the sun-exposed side of certain green fruits after st...

S. A. Rodikov

2008-06-01T23:59:59.000Z

263

Influence of organs in the ICRP's remainder on effective dose equivalent computed for diagnostic radiation exposures  

SciTech Connect

The ICRP effective dose equivalent has been compared with a weighted dose equivalent, computed by treating the entire remainder instead of the sample of five remainder organs in the ICRP method as uniformly radiosensitive, for dose distributions from three common diagnostic exposures: chest, dental full-mouth and dental panoramic. Complete dose distributions were computed by a Monte Carlo model. In all three cases the effective dose equivalent was greater than the weighted dose equivalent. The difference was only 20% for the chest exam but was more than fivefold for both dental exposures. Dose distributions for the dental exposures were less homogeneous than for the chest examination. Selection of organs to be included in the remainder markedly affects the effective dose equivalent. In the case of highly inhomogeneous dose distributions, the effective dose equivalent probably significantly over-estimates radiation detriment.

Gibbs, S.J.

1989-04-01T23:59:59.000Z

264

A proposed measurement of the reverse Cherenkov radiation effect in a metamaterial-loaded circular waveguide  

SciTech Connect

The authors have recently proposed an experiment on verification of the Reverse Cherenkov Radiation (RCR) effect in a Left-Handed-Material-loaded waveguide. Applications of the RCR effect may range from novel higher-order-mode suppressors in microwave and millimeter-wave sources to improved particle detectors for satellite non-proliferation missions. The experimental configuration includes a circular waveguide filled with an artificial metamaterial with simultaneously negative permittivity and permeability, in which the electromagnetic wave with a frequency of 95 GHz will interact with an electron beam. They have demonstrated that for certain values of effective permittivity and permeability only the backward-propagating mode can be exited by the electron beam. At the conference they will present some newly developed metamaterial designs, which they plan to employ for producing the proper effective medium parameters for this experiment.

Shchegolkov, Dmitry [Los Alamos National Laboratory; Azad, Abul K [Los Alamos National Laboratory; O' Hara, John F [Los Alamos National Laboratory; Smirnova, Evgenya I [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

265

Patterns of Care Study of radiation therapy for uterine cervix cancer in Japan: The influence of age on the process  

Science Journals Connector (OSTI)

Background. To improve the quality of radiation oncology in Japan, a Patterns of Care Study (PCS) ... in the United States, was introduced to Japan. In this study, the process, including...

T. Teshima; Hiroshi Ikeda; Mitsuyuki Abe…

1999-02-01T23:59:59.000Z

266

Mechanistic studies using kinetic isotope effects  

E-Print Network (OSTI)

MECHANISTIC STUDIES USING KINETIC ISOTOPE EFFECTS A Thesis by BRIAN E. SCHULMFIER Submitted to the Office of Graduate Studies of Texas ARM University in partial fulfillment of the requtrements for the degree of MASTER OF SCIENCE December... 1999 Major Subject: Chemistry MECHANISTIC STUDIES USING KINETIC ISOTOPE EFFECTS A Thesis by BRIAN E. SCHULMEIER Submitted to Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved...

Schulmeier, Brian E.

2012-06-07T23:59:59.000Z

267

Synergistic Effect of Combination Topotecan and Chronomodulated Radiation Therapy on Xenografted Human Nasopharyngeal Carcinoma  

SciTech Connect

Purpose: To investigate the in vivo chronomodulated radiosensitizing effect of topotecan (TPT) on human nasopharyngeal carcinoma (NPC) and its possible mechanisms. Methods and Materials: Xenografted BALB/c (nu/nu) NPC mice were synchronized with an alternation of 12 hours of light from 0 to 12 hours after light onset (HALO) and 12 hours of darkness to establish a unified biological rhythm. Chronomodulated radiosensitization of TPT was investigated by analysis of tumor regrowth delay (TGD), pimonidazole hydrochloride, histone H2AX phosphorylation, (?-H2AX) topoisomerase I (Top I), cell cycle, and apoptosis after treatment with (1) TPT (10 mg/kg) alone; (2) radiation therapy alone (RT); and (3) TPT+RT at 3, 9, 15, and 21 HALO. The tumor-loaded mice without any treatment were used as controls. Results: The TPT+RT combination was more effective than TPT or RT as single agents. The TPT+RT combination at 15 HALO was best (TGD = 58.0 ± 3.6 days), and TPT+RT at 3 HALO was worst (TGD = 35.0 ± 1.5 days) among the 4 TPT+RT groups (P<.05). Immunohistochemistry analysis revealed a significantly increased histone H2AX phosphorylation expression and decreased pimonidazole hydrochloride expression in the TPT+RT group at the same time point. The results suggested that the level of tumor hypoxia and DNA damage varied in a time-dependent manner. The expression of Top I in the TPT+RT group was also significantly different from the control tumors at 15 HALO (P<.05). Cell apoptosis index was increased and the proportion of cells in S phase was decreased (P<.05) with the highest value in 15 HALO and the lowest in 3 HALO. Conclusions: This study suggested that TPT combined with chronoradiotherapy could enhance the radiosensitivity of xenografted NPC. The TPT+RT group at 15 HALO had the best therapeutic effect. The chronomodulated radiosensitization mechanisms of TPT might be related to circadian rhythm of tumor hypoxia, cell cycle redistribution, DNA damage, and expression of Top I.

Zhang, YanLing; Chen, Xin; Ren, PeiRong; Su, Zhou; Cao, HongYing; Zhou, Jie; Zou, XiaoYan; Fu, ShaoZhi; Lin, Sheng; Fan, Juan; Yang, Bo; Sun, XiaoYang [Department of Oncology, Affiliated Hospital of Luzhou Medical College, Luzhou (China); Zhou, Yan; Chen, Yue [Department of Medical Imaging, Luzhou Medical College, Luzhou (China); Yang, LingLin, E-mail: yanglinglin2003@tom.com [Department of Oncology, Affiliated Hospital of Luzhou Medical College, Luzhou (China); Wu, JingBo, E-mail: wjb6147@163.com [Department of Oncology, Affiliated Hospital of Luzhou Medical College, Luzhou (China)

2013-10-01T23:59:59.000Z

268

Treatment of metal surfaces with excimer laser radiation for radiative applications  

Science Journals Connector (OSTI)

In this study the effects of intense excimer laser irradiation (108–109 W cm?2) on some radiative properties of copper, aluminum, magnesium, tantalum,...

Kinsman, G; Duley, W W

1993-01-01T23:59:59.000Z

269

Radiation protection of staff in 111In radionuclide therapy—is the lead apron shielding effective?  

Science Journals Connector (OSTI)

......trained in basic radiation safety, including the...minimise their radiation dose. Within a...the LTM Windows software, Version 1.20...shield for the radiation. Calculations...done using MatLab software. The final voxel......

M. Lyra; P. Charalambatou; M. Sotiropoulos; S. Diamantopoulos

2011-09-01T23:59:59.000Z

270

RADIATION EXPOSURE DURING PAEDIATRIC CT IN SUDAN: CT DOSE, ORGAN AND EFFECTIVE DOSES  

Science Journals Connector (OSTI)

......research-article Paper RADIATION EXPOSURE DURING PAEDIATRIC...Energy Commission, Radiation Safety Institute, PO Box 3001...assess the magnitude of radiation exposure during paediatric...CT-Expo 2.1 dosimetry software. Doses were evaluated......

I. I. Suliman; H. M. Khamis; T. H. Ombada; K. Alzimami; M. Alkhorayef; A. Sulieman

2014-11-01T23:59:59.000Z

271

Longitudinal variation of tides in the MLT region: 2. Relative effects of solar radiative and latent heating  

E-Print Network (OSTI)

of solar radiative and latent heating Xiaoli Zhang,1 Jeffrey M. Forbes,1 and Maura E. Hagan2 Received 11 study examines the relative importance of radiative heating and latent heating in accounting (GSWM) and new tidal heating rates derived from International Satellite Cloud Climatology Project (ISCCP

Forbes, Jeffrey

272

Radiosurgery for Para-IAC Meningiomas: The Effect of Radiation Dose to the Cochlea on Hearing Outcome  

SciTech Connect

Purpose: This study was performed to assess the radiosurgical results of meningiomas extending into the internal acoustic canal (para-IAC meningiomas), with a particular focus on the effect of radiation dose to the cochlea on hearing outcome. Methods and Materials: A total of 50 patients who underwent radiosurgery for para-IAC meningiomas between 1998 and 2009, which were followed for 2 years, were enrolled. The mean age was 55.8 years (range, 15-75). The mean tumor volume was 6.1 cm{sup 3} (range, 1.0-19.0), the mean tumor length in the IAC was 6.9 mm (range, 1.3-13.3), and the mean prescribed marginal dose was 13.1 Gy (range, 10-15) at an isodose line of 50%. The mean follow-up duration was 46 months (range, 24-122). Results: Eight (16.0%) patients had nonserviceable hearing at the time of surgery. At the last follow-up, the tumor control rate was 94%; unchanged in 17 patients, decreased in 30 patients, and increased in 3 patients. Among 42 patients with serviceable hearing at the time of radiosurgery, it was preserved in 41 (97.6%) patients at the last follow-up. The maximal and mean radiation doses to the cochleae of these 41 patients were 5.8 Gy {+-} 0.3 (range, 3.1-11.5) and 4.3 Gy {+-} 0.2 (range, 2.2-7.5), respectively. The maximal dose to the cochlea of the patient who lost hearing after radiosurgery was 4.7 Gy. Conclusions: The radiation dose to the cochlea may have the minimal toxic effect on the hearing outcome in patients who undergo radiosurgery for para-IAC meningiomas.

Kim, Young-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dong Gyu, E-mail: gknife@plaza.snu.ac.kr [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Jung Ho [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Jeong-Hoon [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Chae-Yong [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of) [Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Paek, Sun Ha; Jung, Hee-Won [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of) [Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of); Department of Neurosurgery, Seoul National University College of Medicine, Seoul (Korea, Republic of)

2012-11-01T23:59:59.000Z

273

Study of CSR Effects in the Jefferson Laboratory FEL Driver  

SciTech Connect

In a recent experiment conducted on the Jefferson Laboratory IR FEL driver the effects of Coherent Synchrotron Radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR chicane. This experiment also provides a valuable opportunity to benchmark existing CSR models in a system that may not be fully represented by a 1-D CSR model. Here we present results from this experiment and compare to initial simulations of CSR in the magnetic compression chicane of the machine. Finally, we touch upon the possibility for CSR induced microbunching gain in the magnetic compression chicane, and show that parameters in the machine are such that it should be thoroughly damped.

Hall, C. C. [Colorado State U.; Biedron, S. [Colorado State U.; Burleson, Theodore A. [Colorado State U.; Milton, Stephen V. [Colorado State U.; Morin, Auralee L. [Colorado State U.; Benson, Stephen V. [JLAB; Douglas, David R. [JLAB; Evtushenko, Pavel E. [JLAB; Hannon, Fay E. [JLAB; Li, Rui [JLAB; Tennant, Christopher D. [JLAB; Zhang, Shukui [JLAB; Carlsten, Bruce E. [LANL; Lewellen, John W. [LANL

2013-08-01T23:59:59.000Z

274

Structural Stability of Human Fibroblast Growth Factor-1 Is Essential for Protective Effects Against Radiation-Induced Intestinal Damage  

SciTech Connect

Purpose: Human fibroblast growth factor-1 (FGF1) has radioprotective effects on the intestine, although its structural instability limits its potential for practical use. Several stable FGF1 mutants were created increasing stability in the order, wild-type FGF1, single mutants (Q40P, S47I, and H93G), Q40P/S47I, and Q40P/S47I/H93G. This study evaluated the contribution of the structural stability of FGF1 to its radioprotective effect. Methods and Materials: Each FGF1 mutant was administered intraperitoneally to BALB/c mice in the absence of heparin 24 h before or after total body irradiation (TBI) with {gamma}-rays at 8-12 Gy. Several radioprotective effects were examined in the jejunum. Results: Q40P/S47I/H93G could activate all subtypes of FGF receptors in vitro much more strongly than the wild-type without endogenous or exogenous heparin. Preirradiation treatment with Q40P/S47I/H93G significantly increased crypt survival more than wild-type FGF1 after TBI at 10 or 12 Gy, and postirradiation treatment with Q40P/S47I/H93G was effective in promoting crypt survival after TBI at 10, 11, or 12 Gy. In addition, crypt cell proliferation, crypt depth, and epithelial differentiation were significantly promoted by postirradiation treatment with Q40P/S47I/H93G. The level of stability of FGF1 mutants correlated with their mitogenic activities in vitro in the absence of heparin; however, preirradiation treatment with the mutants increased the crypt number to almost the same level as Q40P/S47I/H93G. When given 24 h after TBI at 10 Gy, all FGF1 mutants increased crypt survival more than wild-type FGF1, and Q40P/S47I/H93G had the strongest mitogenic effects in intestinal epithelial cells after radiation damage. Moreover, Q40P/S47I/H93G prolonged mouse survival after TBI because of the repair of intestinal damage. Conclusion: These findings suggest that the structural stability of FGF1 can contribute to the enhancement of protective effects against radiation-induced intestinal damage. Therefore, Q40P/S47I/H93G is pharmacologically one of the most promising candidates for clinical applications for radiation-induced gastrointestinal syndrome.

Nakayama, Fumiaki, E-mail: f_naka@nirs.go.jp [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)] [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Umeda, Sachiko [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)] [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Yasuda, Takeshi [Department of Radiation Emergency Medicine, Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan)] [Department of Radiation Emergency Medicine, Research Center for Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan); Asada, Masahiro; Motomura, Kaori; Suzuki, Masashi [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan)] [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan); Zakrzewska, Malgorzata [Faculty of Biotechnology, University of Wroclaw (Poland)] [Faculty of Biotechnology, University of Wroclaw (Poland); Imamura, Toru [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan)] [Signaling Molecules Research Laboratory, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki (Japan); Imai, Takashi [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)] [Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan)

2013-02-01T23:59:59.000Z

275

Generation of high-power tunable terahertz-radiation by nonrelativistic beam-echo harmonic effect  

SciTech Connect

A new type of terahertz radiation source based on the nonrelativistic electron beam-wave interaction is proposed. Here, the beam echo harmonic effect is applied to a traveling wave tube like device. The scheme is configured as a combination of a frequency multiplier and amplifier with, for instance, W-band (millimeter wave) input signals and terahertz output power. A one-dimensional model of this device shows that a 10th order harmonic-wave can be generated while other harmonic waves are suppressed. The device only requires a readily available input source (W-band), and the output frequency can be tuned continuously over a wide band.

Gong Huarong; Xu Jin; Wei Yanyu; Gong Yubin [National Key Laboratory of Science and Technology on Vacuum Electronics, School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054 (China); Travish, Gil [Department of Physics and Astronomy, University of California, Los Angeles, California 90095 (United States); Feng Jinjun [Vacuum Electronics National Laboratory, Vacuum Electronics research Institute, Beijing 100016 (China)

2013-01-15T23:59:59.000Z

276

Development and Validation of a Heart Atlas to Study Cardiac Exposure to Radiation Following Treatment for Breast Cancer  

SciTech Connect

Purpose: Cardiac toxicity is an important sequela of breast radiotherapy. However, the relationship between dose to cardiac structures and subsequent toxicity has not been well defined, partially due to variations in substructure delineation, which can lead to inconsistent dose reporting and the failure to detect potential correlations. Here we have developed a heart atlas and evaluated its effect on contour accuracy and concordance. Methods and Materials: A detailed cardiac computed tomography scan atlas was developed jointly by cardiology, cardiac radiology, and radiation oncology. Seven radiation oncologists were recruited to delineate the whole heart, left main and left anterior descending interventricular branches, and right coronary arteries on four cases before and after studying the atlas. Contour accuracy was assessed by percent overlap with gold standard atlas volumes. The concordance index was also calculated. Standard radiation fields were applied. Doses to observer-contoured cardiac structures were calculated and compared with gold standard contour doses. Pre- and post-atlas values were analyzed using a paired t test. Results: The cardiac atlas significantly improved contour accuracy and concordance. Percent overlap and concordance index of observer-contoured cardiac and gold standard volumes were 2.3-fold improved for all structures (p < 0.002). After application of the atlas, reported mean doses to the whole heart, left main artery, left anterior descending interventricular branch, and right coronary artery were within 0.1, 0.9, 2.6, and 0.6 Gy, respectively, of gold standard doses. Conclusions: This validated University of Michigan cardiac atlas may serve as a useful tool in future studies assessing cardiac toxicity and in clinical trials which include dose volume constraints to the heart.

Feng, Mary, E-mail: maryfeng@umich.ed [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Moran, Jean M. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Koelling, Todd [Department of Internal Medicine, Division of Cardiology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Chughtai, Aamer [Department of Radiology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Chan, June L.; Freedman, Laura; Hayman, James A.; Jagsi, Reshma; Jolly, Shruti; Larouere, Janice; Soriano, Julie; Marsh, Robin; Pierce, Lori J. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)

2011-01-01T23:59:59.000Z

277

Radiation environment simulations at the Tevatron, studies of the beam profile and measurement of the Bc meson mass  

SciTech Connect

The description of a computer simulation of the CDF detector at Fermilab and the adjacent accelerator parts is detailed, with MARS calculations of the radiation background in various elements of the model due to the collision of beams and machine-related losses. Three components of beam halo formation are simulated for the determination of the principal source of radiation background in CDF due to beam losses. The effect of a collimator as a protection for the detector is studied. The simulation results are compared with data taken by a CDF group. Studies of a 150 GeV Tevatron proton beam are performed to investigate the transverse diffusion growth and distribution. A technique of collimator scan is used to scrape the beam under various experimental conditions, and computer programs are written for the beam reconstruction. An average beam halo growth speed is given and the potential of beam tail reconstruction using the collimator scan is evaluated. A particle physics analysis is conducted in order to detect the B{sub c} {yields} J/{psi}{pi} decay signal with the CDF Run II detector in 360 pb{sup -1} of data. The cut variables and an optimization method to determine their values are presented along with a criterion for the detection threshold of the signal. The mass of the B{sub c} meson is measured with an evaluation of the significance of the signal.

Nicolas, Ludovic Y.; /Glasgow U.

2005-09-01T23:59:59.000Z

278

Alternatives of non-threshold and threshold concepts of cancerogenic and mutagenic effects of low LET radiation: the analysis of postulates and arguments  

Science Journals Connector (OSTI)

The comparative analysis of radiation-induced stochastic effects in organisms and cells is given under the aspect of the comparison of non-threshold vs. threshold concepts of radiation effect induction including their postulate basis analysis. Most representative data of basic research areas of radiation-induced stochastic effects are considered, including data on radiation epidemiology and experimental and theoretical radiobiology. The main conclusion of the elaborated analysis consists in the principal difference of dose response patterns for radiation-induced, stochastic effects in the low dose range compared with those in the high dose range. The principal inadequacy of extrapolations from high to low dose ranges is noted, as well as the better justification and the corresponding preference attributed to the threshold concept of low LET radiation effects. The new approach principle of the approximate radiation-induced stochastic effect, quasi-threshold evaluation, is presented.

Lev M. Rozhdestvensky

2006-01-01T23:59:59.000Z

279

The radiation crosslinking of poly(vinyl chloride) with trimethylolpropanetrimethacrylate. III. Effect of diundecyl phthalate: chemical kinetics of a three-component system  

SciTech Connect

The radiation chemistry of poly(vinyl chloride) (PVC) blended with trimethylolpropanetrimethacrylate (TMPTMA) and diundecyl phthalate (DUP) has been examined. This three-component mixture contains a base resin (PVC), a crosslinking sensitizer (TMPTMA), and a physical modifier (DUP). These are the basic components in any radiation-curable coating. The kinetics and mechanism of the crosslinking reactions were studied with reference to the dependence on radiation dose and blend composition. The polyfunctional TMPTMA underwent polymerization incorporating the PVC into a 3-dimensional network. DUP remained chemically inert during the irradiation, not being bound to the network. However, DUP by plasticizing the macromolecules and diluting the monomer, changed the kinetics extensively. DUP enhanced TMPTMA homopolymerization, TMPTMA grafting, and PVC crosslinking reaction rates. The effect of the competition between polymerization, grafting, and degradation reactions was examined in terms of enhanced mobility of the reacting species. The influence of these kinetics considerations in selecting a blend composition for a coating application was discussed.

Bowmer, T.N.; Vroom, W.I.; Hellman, M.Y.

1983-08-01T23:59:59.000Z

280

Two-Year and Lifetime Cost-Effectiveness of Intensity Modulated Radiation Therapy Versus 3-Dimensional Conformal Radiation Therapy for Head-and-Neck Cancer  

SciTech Connect

Purpose: To assess the cost-effectiveness of intensity modulated radiation therapy (IMRT) versus 3-dimensional conformal radiation therapy (3D-CRT) in the treatment of head-and neck-cancer (HNC). Methods and Materials: We used a Markov model to simulate radiation therapy-induced xerostomia and dysphagia in a hypothetical cohort of 65-year-old HNC patients. Model input parameters were derived from PARSPORT (CRUK/03/005) patient-level trial data and quality-of-life and Medicare cost data from published literature. We calculated average incremental cost-effectiveness ratios (ICERs) from the US health care perspective as cost per quality-adjusted life-year (QALY) gained and compared our ICERs with current cost-effectiveness standards whereby treatment comparators less than $50,000 per QALY gained are considered cost-effective. Results: In the first 2 years after initial treatment, IMRT is not cost-effective compared with 3D-CRT, given an average ICER of $101,100 per QALY gained. However, over 15 years (remaining lifetime on the basis of average life expectancy of a 65-year-old), IMRT is more cost-effective at $34,523 per QALY gained. Conclusion: Although HNC patients receiving IMRT will likely experience reduced xerostomia and dysphagia symptoms, the small quality-of-life benefit associated with IMRT is not cost-effective in the short term but may be cost-effective over a patient's lifetime, assuming benefits persist over time and patients are healthy and likely to live for a sustained period. Additional data quantifying the long-term benefits of IMRT, however, are needed.

Kohler, Racquel E. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Sheets, Nathan C. [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States); Wheeler, Stephanie B. [Department of Health Policy and Management, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina (United States); Nutting, Chris [Royal Marsden Hospital, London, United Kindom (United Kingdom); Hall, Emma [Clinical Trials and Statistics Unit, Division of Clinical Studies, Institute of Cancer Research, London (United Kingdom); Chera, Bhishamjit S., E-mail: bchera@med.unc.edu [Department of Radiation Oncology, University of North Carolina Hospitals, Chapel Hill, North Carolina (United States)

2013-11-15T23:59:59.000Z

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281

Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report  

SciTech Connect

The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.

Ogren, John A.; Sheridan, Patrick S.; Andrews, Elisabeth

2009-03-05T23:59:59.000Z

282

Theoretical study of radiative electron attachment to CN, C2H, and C4H radicals  

E-Print Network (OSTI)

A first-principle theoretical approach to study the process of radiative electron attachment is developed and applied to the negative molecular ions CN$^-$, C$_4$H$^-$, and C$_2$H$^-$. Among these anions, the first two have already been observed in the interstellar space. Cross sections and rate coefficients for formation of these ions by radiative electron attachment to the corresponding neutral radicals are calculated. For completeness of the theoretical approach, two pathways for the process have been considered: (i) A direct pathway, in which the electron in collision with the molecule spontaneously emits a photon and forms a negative ion in one of the lowest vibrational levels, and (ii) an indirect, or two-step pathway, in which the electron is initially captured through non-Born-Oppenheimer coupling into a vibrationally resonant excited state of the anion, which then stabilizes by radiative decay. We develop a general model to describe the second pathway and show that its contribution to the formation o...

Douguet, Nicolas; Raoult, Maurice; Dulieu, Olivier; Orel, Ann E; Kokoouline, Viatcheslav

2015-01-01T23:59:59.000Z

283

Developing a Methodology for Characterizing the Effects of Building Materials’ Natural Radiation Background on a Radiation Portal Monitoring System  

E-Print Network (OSTI)

the sponsors of this research, Oak Ridge National Laboratory (ORNL). vi NOMENCLATURE EW Energy Windowing FWHM Full-Width at Half Maximum HEU Highly Enriched Uranium HPGe High-Purity Germanium ISOCS In-Situ Object Counting System MCA Multichannel... Naturally Occurring Radioactive Material ? Diameter ORNL Oak Ridge National Laboratory PMT Photomultiplier Tube PNNL Pacific Northwest National Laboratory PVT Polyvinyl Toluene RDD Radiological Dispersal Device vii RPM Radiation Portal Monitor...

Fitzmaurice, Matthew Blake 1988-

2012-11-06T23:59:59.000Z

284

Parallelization of Radiation Therapy Treatment Planning(RTTP) : A Case Study  

E-Print Network (OSTI)

Radiation therapy uses ionizing radiation to treat cancer- ous tumors. This paper reports our experiences with the parallelization of a real-world 3-D radiation therapy treat- ment planning (RTTP) system on a wide range of plat at the tumor in a patient from different directions, thereby concentrating radiation dose in the tumor

Chaudhary, Vipin

285

Non-targeted effects of ionising radiation (NOTE) Â… a new European Integrated project, 2006-2010  

NLE Websites -- All DOE Office Websites (Extended Search)

targeted effects of ionising radiation (NOTE) - targeted effects of ionising radiation (NOTE) - a new European Integrated project, 2006-2010 Sisko Salomaa 1 , Eric G. Wright 2 , Guido Hildebrandt 3 , Munira Kadhim 4 , Mark P. Little 5 , Kevin M. Prise 6 , and Oleg V. Belyakov 1 1 Research and Environmental Surveillance, STUK - Radiation and Nuclear Safety Authority, Helsinki FI-00881, Finland 2 University of Dundee, Division of Pathology and Neuroscience, Molecular and Cellular Pathology Laboratories, Ninewells Hospital and Medical School, Dundee DD1 9SY, Scotland, UK 3 Department of Radiotherapy and Radiooncology, University of Leipzig, Leipzig 04103, Germany 4 MRC Radiation and Genome Stability Unit, Harwell, Didcot, Oxfordshire OX11 ORD, UK 5 Department of Epidemiology and Public Health, Imperial College Faculty of Medicine,

286

QED radiative effects in the processes of exclusive photon electroproduction from polarized protons with the next-to-leading accuracy  

SciTech Connect

Radiative effects in the electroproduction of photons in polarized ep-scattering are calculated with the next-to-leading (NLO) accuracy. The contributions of loops and two photon emission were presented in analytical form. The covariant approach of Bardin and Shumeiko was used to extract the infrared divergence. All contributions to the radiative correction were presented in the form of the correction to the leptonic tensor thus allowing for further applications in other experiments, e.g., deep inelastic scattering. The radiative corrections (RC) to the cross sections and polarization asymmetries were analyzed numerically for kinematical conditions of the current measurement at Jefferson Lab. Specific attention was paid on analyzing kinematical conditions for the process with large radiative effect when momenta of two photons in the final state are collinear to momenta of initial and final electrons, respectively.

Akushevich, Igor V. [Duke University, JLAB; Ilyichev, Alexander [Byelorussian State University; Shumeiko, Nikolai M [Byelorussian State University

2014-08-01T23:59:59.000Z

287

Low dose radiation effects of multipotent neural stem and progenitor cells  

NLE Websites -- All DOE Office Websites (Extended Search)

effects of multipotent neural stem and progenitor cells effects of multipotent neural stem and progenitor cells Charles L. Limoli, Department of Radiation Oncology, University of California, Irvine 92697-2695 Multipotent neural cells (both stem cells and their precursor cell progeny) retain their capacity to proliferate and differentiate throughout the mammalian lifespan. High numbers of these cells are located within the dentate subgranular zone (SGZ) of the hippocampus and the subventricular (SVZ) zone adjacent to the lateral ventricles, where they produce cells that can migrate away and differentiate into neurons (neurogenesis) and glia (gliogenesis). The realization that the brain contains such cells has sparked intense interest and speculation regarding their potential function. While significant data

288

Aerosol Radiative Effects and Single-Scattering Properties in the Tropical Western Pacific  

NLE Websites -- All DOE Office Websites (Extended Search)

Effects and Single-Scattering Properties Effects and Single-Scattering Properties in the Tropical Western Pacific A. M. Vogelmann and P. J. Flatau Center for Atmospheric Sciences Scripps Institution of Oceanography University of California San Diego, California M. A. Miller, M. J. Bartholomew, and R. M. Reynolds Brookhaven National Laboratory Upton, New York P. J. Flatau University Corporation for Atmospheric Research Naval Research Laboratory Monterey, California K. M. Markowicz Institute of Geophysics University of Warsaw Warsaw, Poland Introduction The Atmospheric Radiation Measurement (ARM) Tropical Western Pacific (TWP) sites are downwind from Southeast Asia where biomass burning occurs and can advect over the tropical warm pool. Previous research (Vogelmann 2001, 2002, 2003) indicates that aerosol forcing was particularly large

289

A Comparative Study on the Type IIA Photosensitivity of a B-Ge Optical Fiber Using Ultraviolet, Femtosecond Radiation  

Science Journals Connector (OSTI)

A comparative study on the Type IIA photosensitivity of a B/Ge-codoped optical fibre is performed using 5ps, 500fs and 120fs, 248nm laser radiation. Index modulation curves and...

Violakis, Georgios; Georgiou, Savas; Konstantaki, Maria; Pissadakis, Stavros

290

A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows  

E-Print Network (OSTI)

A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN GREENDYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1988 Major Subject: Aerospace Engineering A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN...

Greendyke, Robert Brian

2012-06-07T23:59:59.000Z

291

Intensity-Modulated Radiation Therapy in Oropharyngeal Carcinoma: Effect of Tumor Volume on Clinical Outcomes  

SciTech Connect

Purpose: To analyze the effect of primary gross tumor volume (pGTV) and nodal gross tumor volume (nGTV) on treatment outcomes in patients treated with definitive intensity-modulated radiation therapy (IMRT) for oropharyngeal cancer (OPC). Methods and Materials: Between September 1998 and April 2009, a total of 442 patients with squamous cell carcinoma of the oropharynx were treated with IMRT with curative intent at our center. Thirty patients treated postoperatively and 2 additional patients who started treatment more than 6 months after diagnosis were excluded. A total of 340 patients with restorable treatment plans were included in this present study. The majority of the patients underwent concurrent platinum-based chemotherapy. The pGTV and nGTV were calculated using the original clinical treatment plans. Cox proportional hazards models and log-rank tests were used to evaluate the correlation between tumor volumes and overall survival (OS), and competing risks analysis tools were used to evaluate the correlation between local failure (LF), regional failure (RF), distant metastatic failure (DMF) vs. tumor volumes with death as a competing risk. Results: Median follow-up among surviving patients was 34 months (range, 5-67). The 2-year cumulative incidence of LF, RF and DF in this cohort of patients was 6.1%, 5.2%, and 12.2%, respectively. The 2-year OS rate was 88.6%. Univariate analysis determined pGTV and T-stage correlated with LF (p < 0.0001 and p = 0.004, respectively), whereas nGTV was not associated with RF. On multivariate analysis, pGTV and N-stage were independent risk factors for overall survival (p = 0.0003 and p = 0.0073, respectively) and distant control (p = 0.0008 and p = 0.002, respectively). Conclusions: In this cohort of patients with OPC treated with IMRT, pGTV was found to be associated with overall survival, local failure, and distant metastatic failure.

Lok, Benjamin H. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); New York University School of Medicine, New York, NY (United States); Setton, Jeremy; Caria, Nicola; Romanyshyn, Jonathan; Wolden, Suzanne L.; Zelefsky, Michael J.; Park, Jeffery; Rowan, Nicholas [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Sherman, Eric J.; Fury, Matthew G. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Ho, Alan [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Pfister, David G. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Wong, Richard J.; Shah, Jatin P.; Kraus, Dennis H. [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Zhang, Zhigang [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Schupak, Karen D.; Gelblum, Daphna Y.; Rao, Shyam D. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Lee, Nancy Y., E-mail: Leen2@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

2012-04-01T23:59:59.000Z

292

Abstract #2302: NVP-BEZ235 a dual inhibitor of phosphatidylinositol 3-Kinase (PI3 Kinase) and mammalian target of rapamycin (mTOR) potently enhances the effects of ionizing radiation.  

Science Journals Connector (OSTI)

...ionizing radiation. Benjamin...effects of ionizing radiation in vitro...BEZ235 at doses of 50 nM...radiation dose range from 0-8...NVP-BEZ235 doses of 1microM...damage after radiation.-H2AX...effect of ionizing radiation in a range of epithelial...

Benjamin Solomon; Anthony Natoli; Jim Hagekyriakou; Carleen Cullinane; and Grant McArthur

2009-05-01T23:59:59.000Z

293

Insufficiency Fractures After Pelvic Radiation Therapy for Uterine Cervical Cancer: An Analysis of Subjects in a Prospective Multi-institutional Trial, and Cooperative Study of the Japan Radiation Oncology Group (JAROG) and Japanese Radiation Oncology Study Group (JROSG)  

SciTech Connect

Purpose: To investigate pelvic insufficiency fractures (IF) after definitive pelvic radiation therapy for early-stage uterine cervical cancer, by analyzing subjects of a prospective, multi-institutional study. Materials and Methods: Between September 2004 and July 2007, 59 eligible patients were analyzed. The median age was 73 years (range, 37-84 years). The International Federation of Gynecologic Oncology and Obstetrics stages were Ib1 in 35, IIa in 12, and IIb in 12 patients. Patients were treated with the constant method, which consisted of whole-pelvic external-beam radiation therapy of 50 Gy/25 fractions and high-dose-rate intracavitary brachytherapy of 24 Gy/4 fractions without chemotherapy. After radiation therapy the patients were evaluated by both pelvic CT and pelvic MRI at 3, 6, 12, 18, and 24 months. Diagnosis of IF was made when the patients had both CT and MRI findings, neither recurrent tumor lesions nor traumatic histories. The CT findings of IF were defined as fracture lines or sclerotic linear changes in the bones, and MRI findings of IF were defined as signal intensity changes in the bones, both on T1- and T2-weighted images. Results: The median follow-up was 24 months. The 2-year pelvic IF cumulative occurrence rate was 36.9% (21 patients). Using Common Terminology Criteria for Adverse Events version 3.0, grade 1, 2, and 3 IF were seen in 12 (21%), 6 (10%), and 3 patients (5%), respectively. Sixteen patients had multiple fractures, so IF were identified at 44 sites. The pelvic IF were frequently seen at the sacroileal joints (32 sites, 72%). Nine patients complained of pain. All patients' pains were palliated by rest or non-narcotic analgesic drugs. Higher age (>70 years) and low body weight (<50 kg) were thought to be risk factors for pelvic IF (P=.007 and P=.013, Cox hazard test). Conclusions: Cervical cancer patients with higher age and low body weight may be at some risk for the development of pelvic IF after pelvic radiation therapy.

Tokumaru, Sunao, E-mail: tokumaru@cc.saga-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Saga University, Saga (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Saga University, Saga (Japan); Toita, Takafumi [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa (Japan)] [Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Okinawa (Japan); Oguchi, Masahiko [Radiation Oncology Department, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo (Japan)] [Radiation Oncology Department, Cancer Institute Hospital, Japanese Foundation for Cancer Research, Tokyo (Japan); Ohno, Tatsuya [Gunma University Heavy Ion Medical Center, Maebashi (Japan)] [Gunma University Heavy Ion Medical Center, Maebashi (Japan); Kato, Shingo [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan)] [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan); Niibe, Yuzuru [Department of Radiology, School of Medicine, Kitasato University, Sagamihara (Japan)] [Department of Radiology, School of Medicine, Kitasato University, Sagamihara (Japan); Kazumoto, Tomoko [Department of Radiology, Saitama Cancer Center, Saitama (Japan)] [Department of Radiology, Saitama Cancer Center, Saitama (Japan); Kodaira, Takeshi [Department of Radiation Oncology, Aichi Cancer Center, Nagoya (Japan)] [Department of Radiation Oncology, Aichi Cancer Center, Nagoya (Japan); Kataoka, Masaaki [Department of Radiology, National Shikoku Cancer Center, Matsuyama (Japan)] [Department of Radiology, National Shikoku Cancer Center, Matsuyama (Japan); Shikama, Naoto [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan)] [Department of Radiation Oncology, Saitama Medical University, International Medical Center, Saitama (Japan); Kenjo, Masahiro [Department of Radiation Oncology, Graduate School of Medical Science, Hiroshima University, Hiroshima (Japan)] [Department of Radiation Oncology, Graduate School of Medical Science, Hiroshima University, Hiroshima (Japan); Yamauchi, Chikako [Department of Radiation Oncology, Shiga Medical Center for Adults, Moriyama (Japan)] [Department of Radiation Oncology, Shiga Medical Center for Adults, Moriyama (Japan); Suzuki, Osamu [Department of Radiation Oncology, Osaka Medical Center for Cancer, Osaka (Japan)] [Department of Radiation Oncology, Osaka Medical Center for Cancer, Osaka (Japan); Sakurai, Hideyuki [Proton Medical Research Center and Tsukuba University, Tuskuba (Japan)] [Proton Medical Research Center and Tsukuba University, Tuskuba (Japan); Teshima, Teruki [Department of Medical Physics and Engineering, Graduate School of Medicine, Osaka University, Suita (Japan)] [Department of Medical Physics and Engineering, Graduate School of Medicine, Osaka University, Suita (Japan); Kagami, Yoshikazu [Department of Radiology, Showa University School of Medicine, Tokyo (Japan)] [Department of Radiology, Showa University School of Medicine, Tokyo (Japan); Nakano, Takashi [Department of Radiation Oncology, Gunma University, Graduate School of Medicine, Maebashi (Japan)] [Department of Radiation Oncology, Gunma University, Graduate School of Medicine, Maebashi (Japan); Hiraoka, Masahiro [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, Graduate School of Medicine, Kyoto (Japan)] [Department of Radiation Oncology and Image-applied Therapy, Kyoto University, Graduate School of Medicine, Kyoto (Japan); and others

2012-10-01T23:59:59.000Z

294

Experimental study of acoustic radiation from a boundary layer transition region  

Science Journals Connector (OSTI)

Wall pressurefluctuations were measured on a rigid axisymmetric body in the CEPRA 19 low?noise anechoic wind tunnel using flush?mounted microphones placed from the laminar region to the fully turbulent boundary layer. Microphones placed in the laminar flow region are used to detect noise radiated from the transition region which occurs naturally without separation under a slightly positive pressure gradient. Cross?spectral analyses show upstream acoustic propagation in a very wide frequency band 4–30 kHz detected in the laminar region. A method of conditional analysis is then used to establish the sequence of events from the onset of near?harmonic instability wave packets to the generation about 10 ms later of turbulent spots leading to the acoustic emission. This intermittent acoustic radiation is detected in the nearfield for wind velocities ranging from 20–70 ms. Farfield detection was not achieved probably because of instrument limitations and propagation effects. [Work supported by DRET Direction des Recherches et Etudes Techniques.

J. C. Perraud; A. Julienne

1986-01-01T23:59:59.000Z

295

E-Print Network 3.0 - acute radiation effects Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

... 5 Summary: to years). Exposure to naturally occurring background radiation is an example of chronic exposure. Acute......

296

Zebrafish as a “Biosensor”? Effects of Ionizing Radiation and Amifostine on Embryonic Viability and Development  

Science Journals Connector (OSTI)

...Environmental Health and Radiation Safety at the University...LabSpectrum v2.0.1 software (Scanalytics...and exposed to radiation at 4 hpf. Immediately...minutes before radiation exposure. For...Molecular Imaging Software, version 4.0...

Geoffrey A. Geiger; Sharon E. Parker; Andrew P. Beothy; Jennifer A. Tucker; Mary C. Mullins; and Gary D. Kao

2006-08-15T23:59:59.000Z

297

Inhibitory effect of solar radiation on thymidine and leucine incorporation by freshwater and marine bacterioplankton.  

Science Journals Connector (OSTI)

...Within the solar UV radiation...extracellular organic carbon. Our...bacterial production before more...information on how solar radiation...Leu into the cell is obtained...extracellular organic carbon. Our...bacterial production before more...information on how solar radiation...Leu into the cell is obtained...

R Sommaruga; I Obernosterer; G J Herndl; R Psenner

1997-11-01T23:59:59.000Z

298

Radiative transfer effects on Doppler measurements as sources of surface effects in sunspot seismology  

E-Print Network (OSTI)

We show that the use of Doppler shifts of Zeeman sensitive spectral lines to observe wavesn in sunspots is subject to measurement specific phase shifts arising from, (i) altered height range of spectral line formation and the propagating character of p mode waves in penumbrae, and (ii) Zeeman broadening and splitting. We also show that these phase shifts depend on wave frequencies, strengths and line of sight inclination of magnetic field, and the polarization state used for Doppler measurements. We discuss how these phase shifts could contribute to local helioseismic measurements of 'surface effects' in sunspot seismology.

S. P. Rajaguru; K. Sankarasubramanian; R. Wachter; P. H. Scherrer

2006-11-29T23:59:59.000Z

299

Spreader-Bar Radiation Detection System Enhancements: A Modeling and Simulation Study  

SciTech Connect

This report provides the modeling and simulation results of the investigation of enhanced spreader bar radiation detection systems.

Ely, James H.; Ashbaker, Eric D.; Batdorf, Michael T.; Baciak, James E.; Hensley, Walter K.; Jarman, Kenneth D.; Robinson, Sean M.; Sandness, Gerald A.; Schweppe, John E.

2012-11-13T23:59:59.000Z

300

Figure 5. Net radiation of the study area on June 21, 2003 ESTIMATION OF HEAT FLUXES  

E-Print Network (OSTI)

of incoming solar radiation and long-wave radiation emitted from the atmosphere to land surface and from chimneys etc. In addition anthropogenic sensible heat contributes to increased surface temperature. However this influence is sufficiently small compared to the solar radiation under clear skies during

Hall, Sharon J.

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

A review of ground-based heavy-ion radiobiology relevant to space radiation risk assessment: Part II. Cardiovascular and immunological effects  

E-Print Network (OSTI)

al. , Late effects of the chernobyl radiation accident on TMortality among the chernobyl emergency workers: estimationcerebrovascular disease in chernobyl emergency workers,

Blakely, Eleanor A.

2008-01-01T23:59:59.000Z

302

Cognitive Function Before and After Intensity-Modulated Radiation Therapy in Patients With Nasopharyngeal Carcinoma: A Prospective Study  

SciTech Connect

Purpose: To evaluate the effects of radiation therapy (RT) on neurocognitive function in patients with nasopharyngeal carcinoma (NPC). Methods and Materials: Thirty patients with NPC treated with intensity-modulated RT were included. Dose-volume histograms of the temporal lobes were obtained in every patient. Neurocognitive tests were administered individually to each patient 1 day before initiation of RT and at least 12 months after completion of RT. Cognitive functioning status was evaluated as change in scores over time. Results: Among the total of 30 patients, 23 patients (76.7%) had significantly lower post-RT cognitive functioning scores compared with their pre-RT scores (p = 0.033). The cognitive functioning scores had significantly declined in the domains of short-term memory, language abilities, and list-generating fluency (p = 0.020, 0.023, and 0.001, respectively). Compared with patients with a mean dose to the temporal lobes of 36 Gy or less, patients with a mean dose of greater than 36 Gy had a significantly greater reduction in cognitive functioning scores (p = 0.017). Patients in whom V60 of the temporal lobes (i.e., the percentage of the temporal lobe volume that had received >60 Gy) was greater than 10% also had a greater reduction in cognitive functioning scores than those in whom V60 was 10% or less (p = 0.039). Conclusions: The results of our study indicated that RT could have deleterious effects on cognitive function in patients with NPC. Efforts should be made to reduce the radiation dose and irradiated volume of temporal lobes without compromising the coverage of target volume.

Hsiao, Kuan-Yin [Department of Radiation Oncology, E-Da Hospital, Kaohsiung, Taiwan (China); Department of Medical Imaging and Radiological Science, I-Shou University, Kaohsiung, Taiwan (China); Yeh, Shyh-An, E-mail: yehsa@hotmail.co [Department of Radiation Oncology, E-Da Hospital, Kaohsiung, Taiwan (China); Department of Medical Imaging and Radiological Science, I-Shou University, Kaohsiung, Taiwan (China); Chang, Chiung-Chih [Department of Neurology, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Kaohsiung, Taiwan (China)

2010-07-01T23:59:59.000Z

303

A Sensitivity Study on Modeling Black Carbon in Snow and its Radiative Forcing over the Arctic and Northern China  

SciTech Connect

Black carbon in snow (BCS) simulated in the Community Atmosphere Model (CAM5) is evaluated against measurements over Northern China and the Arctic, and its sensitivity to atmospheric deposition and two parameters that affect post-depositional enrichment is explored. The BCS concentration is overestimated (underestimated) by a factor of two in Northern China (Arctic) in the default model, but agreement with observations is good over both regions in the simulation with improvements in BC transport and deposition. Sensitivity studies indicate that uncertainty in the melt-water scavenging efficiency (MSE) parameter substantially affects BCS and its radiative forcing (by a factor of 2-7) in the Arctic through post-depositional enrichment. The MSE parameter has a relatively small effect on the magnitude of BCS seasonal cycle but can alter its phase in Northern China. The impact of the snow aging scaling factor (SAF) on BCS, partly through the post-depositional enrichment effect, shows more complex latitudinal and seasonal dependence. Similar to MSE, SAF affects more significantly the magnitude (phase) of BCS season cycle over the Arctic (Northern China). While uncertainty associated with the representation of BC transport and deposition processes in CAM5 is more important than that associated with the two snow model parameters in Northern China, the two uncertainties have comparable effect in the Arctic.

Qian, Yun; Wang, Hailong; Zhang, Rudong; Flanner, M. G.; Rasch, Philip J.

2014-06-02T23:59:59.000Z

304

A study on leakage radiation dose at ELV-4 electron accelerator bunker  

Science Journals Connector (OSTI)

Shielding is an important aspect in the safety of an accelerator and the most important aspects of a bunker shielding is the door. The bunker’s door should be designed properly to minimize the leakage radiation and shall not exceed the permitted limit of 2.5?Sv/hr. In determining the leakage radiation dose that passed through the door and gaps between the door and the wall 2-dimensional manual calculations are often used. This method is hard to perform because visual 2-dimensional is limited and is also very difficult in the real situation. Therefore estimation values are normally performed. In doing so the construction cost would be higher because of overestimate or underestimate which require costly modification to the bunker. Therefore in this study two methods are introduced to overcome the problem such as simulation using MCNPX Version 2.6.0 software and manual calculation using 3-dimensional model from Autodesk Inventor 2010 software. The values from the two methods were eventually compared to the real values from direct measurements using Ludlum Model 3 with Model 44-9 probe survey meter.

2014-01-01T23:59:59.000Z

305

Dose-Effect Relationship in Chemoradiotherapy for Locally Advanced Rectal Cancer: A Randomized Trial Comparing Two Radiation Doses  

SciTech Connect

Purpose: Locally advanced rectal cancer represents a major therapeutic challenge. Preoperative chemoradiation therapy is considered standard, but little is known about the dose-effect relationship. The present study represents a dose-escalation phase III trial comparing 2 doses of radiation. Methods and Materials: The inclusion criteria were resectable T3 and T4 tumors with a circumferential margin of {<=}5 mm on magnetic resonance imaging. The patients were randomized to receive 50.4 Gy in 28 fractions to the tumor and pelvic lymph nodes (arm A) or the same treatment supplemented with an endorectal boost given as high-dose-rate brachytherapy (10 Gy in 2 fractions; arm B). Concomitant chemotherapy, uftoral 300 mg/m{sup 2} and L-leucovorin 22.5 mg/d, was added to both arms on treatment days. The primary endpoint was complete pathologic remission. The secondary endpoints included tumor response and rate of complete resection (R0). Results: The study included 248 patients. No significant difference was found in toxicity or surgical complications between the 2 groups. Based on intention to treat, no significant difference was found in the complete pathologic remission rate between the 2 arms (18% and 18%). The rate of R0 resection was different in T3 tumors (90% and 99%; P=.03). The same applied to the rate of major response (tumor regression grade, 1+2), 29% and 44%, respectively (P=.04). Conclusions: This first randomized trial comparing 2 radiation doses indicated that the higher dose increased the rate of major response by 50% in T3 tumors. The endorectal boost is feasible, with no significant increase in toxicity or surgical complications.

Jakobsen, Anders, E-mail: anders.jakobsen@slb.regionsyddanmark.dk [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark) [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark); University of Southern Denmark, Odense (Denmark); Ploen, John [University of Southern Denmark, Odense (Denmark)] [University of Southern Denmark, Odense (Denmark); Vuong, Te [Department of Radiation Oncology, Jewish General Hospital, Montreal, Quebec (Canada)] [Department of Radiation Oncology, Jewish General Hospital, Montreal, Quebec (Canada); Appelt, Ane [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark) [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark); University of Southern Denmark, Odense (Denmark); Lindebjerg, Jan; Rafaelsen, Soren R. [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark)] [Danish Colorectal Cancer Group South, Vejle Hospital, Vejle (Denmark)

2012-11-15T23:59:59.000Z

306

Japanese Structure Survey of Radiation Oncology in 2007 Based on Institutional Stratification of Patterns of Care Study  

SciTech Connect

Purpose: To evaluate the ongoing structure of radiation oncology in Japan in terms of equipment, personnel, patient load, and geographic distribution to identify and improve any deficiencies. Methods and Materials: A questionnaire-based national structure survey was conducted from March to December 2008 by the Japanese Society of Therapeutic Radiology and Oncology (JASTRO). These data were analyzed in terms of the institutional stratification of the Patterns of Care Study. Results: The total numbers of new cancer patients and total cancer patients (new and repeat) treated with radiation in 2007 were estimated at 181,000 and 218,000, respectively. There were 807 linear accelerator, 15 telecobalt, 46 Gamma Knife, 45 {sup 60}Co remote-controlled after-loading, and 123 {sup 192}Ir remote-controlled after-loading systems in actual use. The linear accelerator systems used dual-energy function in 539 units (66.8%), three-dimensional conformal radiation therapy in 555 (68.8%), and intensity-modulated radiation therapy in 235 (29.1%). There were 477 JASTRO-certified radiation oncologists, 826.3 full-time equivalent (FTE) radiation oncologists, 68.4 FTE medical physicists, and 1,634 FTE radiation therapists. The number of interstitial radiotherapy (RT) administrations for prostate, stereotactic body radiotherapy, and intensity-modulated radiation therapy increased significantly. Patterns of Care Study stratification can clearly identify the maturity of structures based on their academic nature and caseload. Geographically, the more JASTRO-certified physicians there were in a given area, the more RT tended to be used for cancer patients. Conclusions: The Japanese structure has clearly improved during the past 17 years in terms of equipment and its use, although a shortage of personnel and variations in maturity disclosed by Patterns of Care Study stratification were still problematic in 2007.

Teshima, Teruki, E-mail: teshima@sahs.med.osaka-u.ac.j [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita (Japan); Numasaki, Hodaka [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita (Japan); Shibuya, Hitoshi [Department of Radiology, Tokyo Dental and Medical University, Tokyo (Japan); Nishio, Masamichi [Department of Radiology, National Hospital Organization Hokkaido Cancer Center, Sapporo (Japan); Ikeda, Hiroshi [Department of Radiation Oncology, Sakai Municipal Hospital, Sakai (Japan); Sekiguchi, Kenji [Department of Radiation Oncology, St. Luke's International Hospital, Tokyo (Japan); Kamikonya, Norihiko [Department of Radiology, Hyogo College of Medicine, Nishinomiya (Japan); Koizumi, Masahiko [Oncology Center, Osaka University Hospital, Suita (Japan); Tago, Masao [Department of Radiology, Toho University Omori Medical Center, Tokyo (Japan); Ando, Yutaka [Department of Medical Informatics, Heavy Ion Medical Center, National Institute of Radiological Sciences, Chiba (Japan); Tsukamoto, Nobuhito [Department of Radiation Oncology, Saitama Medical University International Medical Center, Saitama (Japan); Terahara, Atsuro [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Nakamura, Katsumasa [Department of Radiology, Kyushu University Hospital at Beppu, Oita (Japan); Mitsumori, Michihide [Department of Radiation Oncology and Image-applied Therapy, Graduate School of Medicine Kyoto University, Kyoto (Japan); Nishimura, Tetsuo [Division of Radiation Oncology, Shizuoka Cancer Center, Shizuoka (Japan); Hareyama, Masato [Department of Radiology, Sapporo Medical University, Hokkaido (Japan)

2010-12-01T23:59:59.000Z

307

Gravitational collapse of a macroscopic string by a Newtonian description including the effect of gravitational radiation  

E-Print Network (OSTI)

We make an attempt to dynamically study, in four space-time dimensions, the classical gravitational collapse of a macroscopic circular fundamental string, by a truncation of the Einstein equations that suppresses retarded features but keeps the main self-gravity peculiarities of the relativistic string dynamics, and allows the investigation of a possible infinite red-shift. The numerical solution of the string evolution in the self-induced metric shows an infinite red shift at a macroscopic size of the string, when the string reaches the velocity of light. We further include the back-reaction of the radiation of gravitons which induces energy dissipation: now the velocity of light is not reached, the infinite red-shift does not form and the string simply shrinks with damped oscillations.

Roberto Iengo

2007-02-12T23:59:59.000Z

308

Thermal reactions of disilane on Si(100) studied by synchrotron-radiation photoemission  

Science Journals Connector (OSTI)

H-terminated Si(100) surfaces were formed by saturation exposure of Si(100) to disilane at room temperature. Annealing these surfaces to progressively higher temperatures resulted in hydrogen desorption. This process, of basic importance to the growth of Si by atomic layer epitaxy using disilane, was studied by synchrotron-radiation photoemission. The Si 2p core-level line shape, the position of the Fermi level within the band gap, the work function, and the ionization potential were measured as a function of annealing temperature. These results revealed two steps in the thermal reaction preceding the recovery of the clean surface. The dihydride radicals on the surface are converted to monohydride radicals at 500–610 K, and the monohydride radicals decompose at 700–800 K.

D.-S. Lin; T. Miller; T.-C. Chiang; R. Tsu; J. E. Greene

1993-10-15T23:59:59.000Z

309

Thermal reactions of disilane on Si(100) studied by synchrotron-radiation photoemission  

SciTech Connect

H-terminated Si(100) surfaces were formed by saturation exposure of Si(100) to disilane at room temperature. Annealing these surfaces to progressively higher temperatures resulted in hydrogen desorption. This process, of basic importance to the growth of Si by atomic layer epitaxy using disilane, was studied by synchrotron-radiation photoemission. The Si 2[ital p] core-level line shape, the position of the Fermi level within the band gap, the work function, and the ionization potential were measured as a function of annealing temperature. These results revealed two steps in the thermal reaction preceding the recovery of the clean surface. The dihydride radicals on the surface are converted to monohydride radicals at 500--610 K, and the monohydride radicals decompose at 700--800 K.

Lin, D.; Miller, T.; Chiang, T. (Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States)); Tsu, R.; Greene, J.E. (Department of Materials Science and Engineering, Coordinated Science Laboratory, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, 1304 West Green Street, Urbana, Illinois 61801-3080 (United States))

1993-10-15T23:59:59.000Z

310

Performance studies of the ATLAS transition radiation tracker barrel using SR1 cosmics data  

E-Print Network (OSTI)

The ATLAS experiment at the Large Hadron Collider (LHC) is designed to measure Nature at the energy scale often associated with electroweak symmetry breaking. When it comes online in 2008, the LHC and ATLAS will work to discover, among other things, the Higgs boson and any other signatures for physics beyond the Standard Model. As part of the ATLAS Inner Detector, the Transition Radiation Tracker will be an important part of ATLAS’s ability to make precise measurements of particle properties. This paper summarizes work done to study and categorize the performance of the TRT, using a combination of cosmic ray test data from the SR1 facility and Monte Carlo. In general, it was found that the TRT is working well, with module-level eciencies around 90 % and module-level noise just above 2 %. Reasonably good agreement was observed with Monte Carlo, though there are some apparently pathological dierences between the two that deserve further attention.

Wall, R

311

Study of the Exclusive Initial-State-Radiation Production of the DDbar System  

E-Print Network (OSTI)

A search for charmonium and other new states is performed in a study of exclusive initial-state-radiation production of D Dbar events from electron-positron annihilations at a center-of-mass energy of 10.58 GeV. The data sample corresponds to an integrated luminosity of 384 fb-1 and was recorded by the BABAR experiment at the PEP-II storage ring. The D Dbar mass spectrum shows clear evidence of the psi(3770) plus other structures near 3.9, 4.1, and 4.4 GeV/c^2. No evidence for Y(4260) -> D Dbar is observed, leading to an upper limit of B(Y(4260) -> D Dbar)/B(Y(4260) -> J/psi pi+ pi-) < 1.0 at 90 % confidence level.

The BABAR Collaboration; B. Aubert

2007-11-14T23:59:59.000Z

312

Low Dose Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Ancient Salt Beds Ancient Salt Beds Repository Science Renewable Energy The WIPP Underground may be ideal to study effects of Very Low Dose Rates on Biological Systems Low Background Radiation Experiment We're all bathing in it. It's in the food we eat, the water we drink, the soil we tread and even the air we breathe. It's background radiation, it's everywhere and we can't get away from it. But what would happen if you somehow "pulled the plug" on natural background radiation? Would organisms suffer or thrive if they grew up without their constant exposure to background radiation? That's what a consortium of scientists conducting an experiment at the Waste Isolation Pilot Plant aim to find out. Despite being an underground repository for transuranic radioactive waste,

313

Influence of Ice Particle Surface Roughening on the Global Cloud Radiative Effect BINGQI YI,* PING YANG,* BRYAN A. BAUM,1  

E-Print Network (OSTI)

Influence of Ice Particle Surface Roughening on the Global Cloud Radiative Effect BINGQI YI,* PING are developed for se- verely roughened ice particles. The parameterizations are based on a general habit mixture and severely roughened ice particles. While the influence of particle roughening on the single

Baum, Bryan A.

314

ASA conference on radiation and health: Health effects of electric and magnetic fields: Statistical support for research strategies. Final report  

SciTech Connect

This report is a collection of papers documenting presentations made at the VIII ASA (American Statistical Association) Conference on Radiation and Health entitled Health Effects of Electric and Magnetic Fields: Statistical Support for Research Strategies. Individual papers are abstracted and indexed for the database.

Not Available

1990-05-01T23:59:59.000Z

315

Effect of surface tension on the acoustic radiation pressure-induced motion of the water-air interface  

E-Print Network (OSTI)

Effect of surface tension on the acoustic radiation pressure-induced motion of the water to be a function of the surface tension. The time of mound formation measurementsin cleanwaterat low.Our objectiveisto investigatetheeffectsof surface tension on mound formation. We usea boundaryintegralmethodto

Khuri-Yakub, Butrus T. "Pierre"

316

Effect of silver nanoparticle and glycyrrhizic acid (SN-GLY) complex on repair of whole body radiation-induced cellular DNA damage and genomic instability in mice  

Science Journals Connector (OSTI)

Silver nanoparticles (SN) were redispersed in aqueous solution of Pluronic F127 and complexed with the phytoceutical, glycyrrhizic acid (GLY) to obtain SN-GLY complex. The ability of the SN-GLY complex to offer protection against ionising radiation in post-irradiation scenarios was evaluated in ex vivo and in vivo models using Swiss albino mice. Treatment of mouse blood leucocytes with SN-GLY immediately after 4 Gy gamma radiation exposure, ex vivo, enhanced the rate of repair of cellular DNA damages as revealed by comet assay. Exposure of mice to 4 Gy whole body gamma radiation induced formation of strand breaks in cellular DNA and the unrepaired double strand breaks eventually caused the formation of micronuclei. The post-irradiation administration of SN-GLY resulted in a faster decrease in the comet parameters indicating enhanced cellular DNA repair process and reduction in micronucleus formation. Thus the studies showed effective radiation protection by SN-GLY in post-irradiation conditions.

Dhanya K. Chandrasekharan; Cherupally Krishnan Krishnan Nair

2010-01-01T23:59:59.000Z

317

A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect.  

SciTech Connect

The Gray Cancer Institute has pioneered the use of X ray focussing techniques to develop systems for micro irradiating individual cells and sub cellular targets in vitro. Cellular micro irradiation is now recognised as a highly versatile technique for understanding how ionising radiation interacts with living cells and tissues. The strength of the technique lies in its ability to deliver precise doses of radiation to selected individual cells (or sub cellular targets). The application of this technique in the field of radiation biology continues to be of great interest for investigating a number of phenomena currently of concern to the radiobiological community. One important phenomenon is the so called ‘bystander effect’ where it is observed that unirradiated cells can also respond to signals transmitted by irradiated neighbours. Clearly, the ability of a microbeam to irradiate just a single cell or selected cells within a population is well suited to studying this effect. Our prototype ‘tabletop’ X-ray microprobe was optimised for focusing 278 eV C-K X rays and has been used successfully for a number of years. However, we have sought to develop a new variable energy soft X-ray microprobe capable of delivering focused CK (0.28 keV), Al-K (1.48 keV) and notably, Ti-K (4.5 keV) X rays. Ti-K X rays are capable of penetrating several cell layers and are therefore much better suited to studies involving tissues and multi cellular layers. In our new design, X-rays are generated by the focussed electron bombardment of a material whose characteristic-K radiation is required. The source is mounted on a 1.5 x 1.0 metre optical table. Electrons are generated by a custom built gun, designed to operate up to 15 kV. The electrons are focused using a permanent neodymium iron boron magnet assembly. Focusing is achieved by adjusting the accelerating voltage and by fine tuning the target position via a vacuum position feedthrough. To analyze the electron beam properties, a custom built microscope is used to image the focussed beam on the target, through a vacuum window. The X-rays are focussed by a zone plate optical assembly mounted to the end of a hollow vertical tube that can be precisely positioned above the X ray source. The cell finding and positioning stage comprises an epi-fluorescence microscope and a feedback controlled 3 axis cell positioning stage, also mounted on the optical table. Independent vertical micro positioning of the microscope objective turret allows the focus of the microscope and the X ray focus to coincide in space (i.e. at the point where the cell should be positioned for exposure). The whole microscope stage assembly can be precisely raised or lowered, to cater for large differences in the focal length of the X ray zone plates. The facility is controlled by PC and the software provides full status and control of the source and makes use of a dual-screen for control and display during the automated cell finding and irradiation procedures.

Folkard, Melvyn; Vojnovic, Borivoj; Schettino, Giuseppe; Atkinson, Kirk; Prise, Kevin, M.; Michael, Barry, D.

2007-01-23T23:59:59.000Z

318

Effectiveness of a clinical intervention in improving pain control in outpatients with cancer treated by radiation therapy  

SciTech Connect

Purpose: To determine the effectiveness of a multicomponent clinical intervention to reduce pain in outpatients with cancer. Methods and Materials: Sixty-four patients were randomly assigned to receive either a clinical intervention including an information session, the use of a pain diary, and the possibility to contact a physician to adjust the pain medication, or the usual treatment of pain by the staff radiation oncologist. All patients reported their average and worst pain levels at baseline and 2 and 3 weeks after the start of the intervention. Results: The study groups were similar with respect to their baseline characteristics and pain levels at randomization. After 3 weeks, the average and worst pain experienced by patients randomized to the clinical intervention group was significantly inferior to the average pain experienced by patients in the control group (2.9/10 vs. 4.4/10 and 4.2/10 vs. 5.5/10, respectively). Results showed that the experimental group patients decreased their pain levels more than the control group patients did over time. Conclusion: An intervention including patient education, a pain diary, and defining a procedure for therapeutic adjustments can be effective to improve pain relief in outpatients with cancer.

Vallieres, Isabelle [Department of Radiation Oncology, Centre Hospitalier Universitaire de Quebec-Hotel-Dieu de Quebec, Quebec City (Canada)]. E-mail: isabelle.vallieres@mail.chuq.qc.ca; Aubin, Michele [Department of Family Medicine, Laval Hospital, Quebec City, Quebec (Canada); Blondeau, Lucie [Department of Radiation Oncology, Centre Hospitalier Universitaire de Quebec-Hotel-Dieu de Quebec, Quebec City (Canada); Simard, Serge [Research Centre of Laval Hospital, Laval University, Sainte-Foy, Quebec (Canada); Giguere, Anik [Palliative Care Research Team, Laval University, Quebec City, Quebec (Canada)

2006-09-01T23:59:59.000Z

319

Retrospective Cohort Study of Bronchial Doses and Radiation-Induced Atelectasis After Stereotactic Body Radiation Therapy of Lung Tumors Located Close to the Bronchial Tree  

SciTech Connect

Purpose: To evaluate the dose–response relationship between radiation-induced atelectasis after stereotactic body radiation therapy (SBRT) and bronchial dose. Methods and Materials: Seventy-four patients treated with SBRT for tumors close to main, lobar, or segmental bronchi were selected. The association between incidence of atelectasis and bronchial dose parameters (maximum point-dose and minimum dose to the high-dose bronchial volume [ranging from 0.1 cm{sup 3} up to 2.0 cm{sup 3}]) was statistically evaluated with survival analysis models. Results: Prescribed doses varied between 4 and 20 Gy per fraction in 2-5 fractions. Eighteen patients (24.3%) developed atelectasis considered to be radiation-induced. Statistical analysis showed a significant correlation between the incidence of radiation-induced atelectasis and minimum dose to the high-dose bronchial volumes, of which 0.1 cm{sup 3} (D{sub 0.1cm3}) was used for further analysis. The median value of D{sub 0.1cm3} (?/? = 3 Gy) was EQD{sub 2,LQ} = 147 Gy{sub 3} (range, 20-293 Gy{sub 3}). For patients who developed atelectasis the median value was EQD{sub 2,LQ} = 210 Gy{sub 3}, and for patients who did not develop atelectasis, EQD{sub 2,LQ} = 105 Gy{sub 3}. Median time from treatment to development of atelectasis was 8.0 months (range, 1.1-30.1 months). Conclusion: In this retrospective study a significant dose–response relationship between the incidence of atelectasis and the dose to the high-dose volume of the bronchi is shown.

Karlsson, Kristin, E-mail: kristin.karlsson@karolinska.se [Department of Medical Physics, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Nyman, Jan [Department of Oncology, Sahlgrenska University Hospital, Gothenburg (Sweden); Baumann, Pia; Wersäll, Peter [Department of Oncology, Radiumhemmet, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Drugge, Ninni [Department of Radiation Physics, Sahlgrenska University Hospital, Gothenburg (Sweden); Gagliardi, Giovanna [Department of Medical Physics, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Johansson, Karl-Axel [Department of Radiation Physics, Sahlgrenska University Hospital, Gothenburg (Sweden); Persson, Jan-Olov [Statistical Research Group, Mathematical Statistics, Stockholm University, Stockholm (Sweden); Rutkowska, Eva [Physics Department, Clatterbridge Cancer Centre, Wirral (United Kingdom); Tullgren, Owe [Department of Oncology, Radiumhemmet, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Lax, Ingmar [Department of Medical Physics, Karolinska University Hospital, Stockholm (Sweden); Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden)

2013-11-01T23:59:59.000Z

320

Reducing Radiation Damage  

SciTech Connect

This talk describes the use of a modified treatment sequence, i.e., radiation dose, geometry, dwell time, etc., to mitigate some of the deleterious effects of cancer radiotherapy by utilizing natural cell repair processes. If bad side effects can be reduced, a more aggressive therapy can be put into place. Cells contain many mechanisms that repair damage of various types. If the damage can not be repaired, cells will undergo apoptosis (cell death). Data will be reviewed that support the fact that a small dose of radiation will activate damage repair genes within a cell. Once the mechanisms are fully active, they will efficiently repair the severe damage from a much larger radiation dose. The data ranges from experiments on specific cell cultures using microarray (gene chip) techniques to experiments on complete organisms. The suggested effect and treatment is consistent with the assumption that all radiation is harmful, no matter how small the dose. Nevertheless, the harm can be reduced. These mechanisms need to be further studied and characterized. In particular, their time dependence needs to be understood before the proposed treatment can be optimized. Under certain situations it is also possible that the deleterious effects of chemotherapy can be mitigated and the damage to radiation workers can be reduced.

Blankenbecler, Richard

2006-06-05T23:59:59.000Z

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321

Proteasome Structures Affected by Ionizing Radiation  

Science Journals Connector (OSTI)

...Effect of ionizing radiation on 26S but...radiation doses, and immediately...the dose range 1 to 20 Gy...ionizing radiation induced a...38), ionizing radiation (39...over a wide range of radiation doses and further...

Milena Pervan; Keisuke S. Iwamoto; and William H. McBride

2005-07-01T23:59:59.000Z

322

Global Warming Potential and Global Warming Commitment Concepts in the Assessment of Climate Radiative Forcing Effects  

Science Journals Connector (OSTI)

The Global Warming Potential (GWP) and Radiative Forcing (RF ... CS) and Individual (IS) schemes. The Global Warming Commitment (GWC) is calculated by the...

Igor L. Karol; Victor A. Frolkis…

2000-01-01T23:59:59.000Z

323

Transitional regimes of natural convection in a differentially heated cubical cavity under the effects of wall and molecular gas radiation  

SciTech Connect

The transition to unsteadiness and the dynamics of weakly turbulent natural convection, coupled to wall or gas radiation in a differentially heated cubical cavity with adiabatic lateral walls, are studied numerically. The working fluid is air with small contents of water vapor and carbon dioxide whose infrared spectral radiative properties are modelled by the absorption distribution function model. A pseudo spectral Chebyshev collocation method is used to solve the flow field equations and is coupled to a direct ray tracing method for radiation transport. Flow structures are identified by means of either the proper orthogonal decomposition or the dynamic mode decomposition methods. We first retrieve the classical mechanism of transition to unsteadiness without radiation, characterized by counter-rotating streamwise-oriented vortices generated at the exit of the vertical boundary layers. Wall radiation through a transparent medium leads to a homogenization of lateral wall temperatures and the resulting transition mechanism is similar to that obtained with perfectly conducting lateral walls. The transition is due to an unstable stratification upstream the vertical boundary layers and is characterized by periodically oscillating transverse rolls of axis perpendicular to the main flow. When molecular gas radiation is accounted for, no periodic solution is found and the transition to unsteadiness displays complex structures with chimneys-like rolls whose axes are again parallel to the main flow. The origin of this instability is probably due to centrifugal forces, as suggested previously for the case without radiation. Above the transition to unsteadiness, at Ra = 3 × 10{sup 8}, it is shown that both wall and gas radiation significantly intensify turbulent fluctuations, decrease the thermal stratification in the core of the cavity, and increase the global circulation.

Soucasse, L.; Rivière, Ph.; Soufiani, A., E-mail: anouar.soufiani@ecp.fr [CNRS, UPR 288, Laboratoire EM2C, 92290 Châtenay-Malabry (France); École Centrale Paris, 92290 Châtenay-Malabry (France)] [France; Xin, S. [CNRS/INSA-Lyon, UMR 5008, CETHIL, 69621 Villeurbanne (France)] [CNRS/INSA-Lyon, UMR 5008, CETHIL, 69621 Villeurbanne (France); Le Quéré, P. [CNRS, UPR 3251, LIMSI, 91403 Orsay Cedex (France)] [CNRS, UPR 3251, LIMSI, 91403 Orsay Cedex (France)

2014-02-15T23:59:59.000Z

324

Contemporary X-ray electron-density studies using synchrotron radiation  

Science Journals Connector (OSTI)

The use of synchrotron radiation for experimental electron-density determination during the last decade is reviewed. Possible future directions of this field are examined.

J?rgensen, M.R.V.

2014-08-29T23:59:59.000Z

325

he Impact of Primary Marine Aerosol on Atmospheric Chemistry, Radiation and Climate: A CCSM Model Development Study  

SciTech Connect

This project examined the potential large-scale influence of marine aerosol cycling on atmospheric chemistry, physics and radiative transfer. Measurements indicate that the size-dependent generation of marine aerosols by wind waves at the ocean surface and the subsequent production and cycling of halogen-radicals are important but poorly constrained processes that influence climate regionally and globally. A reliable capacity to examine the role of marine aerosol in the global-scale atmospheric system requires that the important size-resolved chemical processes be treated explicitly. But the treatment of multiphase chemistry across the breadth of chemical scenarios encountered throughout the atmosphere is sensitive to the initial conditions and the precision of the solution method. This study examined this sensitivity, constrained it using high-resolution laboratory and field measurements, and deployed it in a coupled chemical-microphysical 3-D atmosphere model. First, laboratory measurements of fresh, unreacted marine aerosol were used to formulate a sea-state based marine aerosol source parameterization that captured the initial organic, inorganic, and physical conditions of the aerosol population. Second, a multiphase chemical mechanism, solved using the Max Planck Institute for Chemistryâ??s MECCA (Module Efficiently Calculating the Chemistry of the Atmosphere) system, was benchmarked across a broad set of observed chemical and physical conditions in the marine atmosphere. Using these results, the mechanism was systematically reduced to maximize computational speed. Finally, the mechanism was coupled to the 3-mode modal aerosol version of the NCAR Community Atmosphere Model (CAM v3.6.33). Decadal-scale simulations with CAM v.3.6.33, were run both with and without reactive-halogen chemistry and with and without explicit treatment of particulate organic carbon in the marine aerosol source function. Simulated results were interpreted (1) to evaluate influences of marine aerosol production on the microphysical properties of aerosol populations and clouds over the ocean and the corresponding direct and indirect effects on radiative transfer; (2) atmospheric burdens of reactive halogen species and their impacts on O3, NOx, OH, DMS, and particulate non-sea-salt SO42-; and (3) the global production and influences of marine-derived particulate organic carbon. The model reproduced major characteristics of the marine aerosol system and demonstrated the potential sensitivity of global, decadal-scale climate metrics to multiphase marine-derived components of Earthâ??s troposphere. Due to the combined computational burden of the coupled system, the currently available computational resources were the limiting factor preventing the adequate statistical analysis of the overall impact that multiphase chemistry might have on climate-scale radiative transfer and climate.

Keene, William C. [University of Virginia] [University of Virginia; Long, Michael S. [University of Virginia] [University of Virginia

2013-05-20T23:59:59.000Z

326

The effects of chronic and acute radiation upon the survival of C?H mice  

E-Print Network (OSTI)

-body irradiation. Corresponding values of 6. 3, 3. 6, 2. 5, and 5. 8 weeks per 100 R were observed following 300, 500, 650, and 800 R in the second study. The effect of age on the life span of CF female mice exposed to x-irradiation was reported by Boone (1959... in this investigation are in agreement with Grahn and Sacher. The only difference was that these authors used x-rays, but in this investigation we used gamma rays. Dunhig and Warren (1960) studied the effects of intermittent exposures on the life span of mice...

Jones, Ernest Joseph

1967-01-01T23:59:59.000Z

327

Atmospheric Radiation Measurement (ARM) Data from Black Forest Germany for the Convective and Orographically Induced Precipitation Study (COPS)  

DOE Data Explorer (OSTI)

The primary goal of the ARM Program is to improve the treatment of cloud and radiation physics in global climate models in order to improve the climate simulation capabilities of these models. ARM maintains four major, permanent sites for data collection and deploys the ARM Mobile Facility (AMF) to other sites as determined. In 2007 the AMF operated in the Black Forest region of Germany as part of the Convective and Orographically Induced Precipitation Study (COPS). Scientists studied rainfall resulting from atmospheric uplift (convection) in mountainous terrain, otherwise known as orographic precipitation. This was part of a six -year duration of the German Quantitative Precipitation Forecasting (QPF) Program. COPS was endorsed as a Research and Development Project by the World Weather Research Program. This program was established by the World Meteorological Organization to develop improved and cost-effective forecasting techniques, with an emphasis on high-impact weather. A large collection of data plots based on data streams from specific instruments used at Black Forest are available via a link from ARM's Black Forest site information page. Users will be requested to create a password, but the plots and the data files in the ARM Archive are free for viewing and downloading.

328

Evaluation of cloud fraction and its radiative effect simulated by IPCC AR4 global models against ARM surface observations  

SciTech Connect

Cloud Fraction (CF) is the dominant modulator of radiative fluxes. In this study, we evaluate CF simulations in the IPCC AR4 GCMs against ARM ground measurements, with a focus on the vertical structure, total amount of cloud and its effect on cloud shortwave transmissivity, for both inter-model deviation and model-measurement discrepancy. Our intercomparisons of three CF or sky-cover related dataset reveal that the relative differences are usually less than 10% (5%) for multi-year monthly (annual) mean values, while daily differences are quite significant. The results also show that the model-observation and the inter-model deviations have a similar magnitude for the total CF (TCF) and the normalized cloud effect, and they are twice as large as the surface downward solar radiation and cloud transmissivity. This implies that the other cloud properties, such as cloud optical depth and height, have a similar magnitude of disparity to TCF among the GCMs, and suggests that a better agreement among the GCMs in solar radiative fluxes could be the result of compensating errors in either cloud vertical structure, cloud optical depth or cloud fraction. Similar deviation pattern between inter-model and model-measurement suggests that the climate models tend to generate larger bias against observations for those variables with larger inter-model deviation. The simulated TCF from IPCC AR4 GCMs are very scattered through all seasons over three ARM sites: Southern Great Plains (SGP), Manus, Papua New Guinea and North Slope of Alaska (NSA). The GCMs perform better at SGP than at Manus and NSA in simulating the seasonal variation and probability distribution of TCF; however, the TCF in these models is remarkably underpredicted and cloud transmissivity is less susceptible to the change of TCF than the observed at SGP. Much larger inter-model deviation and model bias are found over NSA than the other sites in estimating the TCF, cloud transmissivity and cloud-radiation interaction, suggesting that the Arctic region continues to challenge cloud simulations in climate models. Most of the GCMs tend to underpredict CF and fail to capture the seasonal variation of CF at middle and low levels in the tropics. The high altitude CF is much larger in the GCMs than the observation and the inter-model variability of CF also reaches maximum at high levels in the tropics. Most of the GCMs tend to underpredict CF by 50-150% relative to the measurement average at low and middle levels over SGP. While the GCMs generally capture the maximum CF in the boundary layer and vertical variability, the inter-model deviation is largest near surface over the Arctic. The internal variability of CF simulated in ensemble runs with the same model is very minimal.

Qian, Yun; Long, Charles N.; Wang, Hailong; Comstock, Jennifer M.; McFarlane, Sally A.; Xie, Shaocheng

2012-02-17T23:59:59.000Z

329

Effect of electromagnetic radiation on an array of weakly interacting carbon nanotubes in the presence of nanosecond pulses  

SciTech Connect

For metallic 'zigzag'-type carbon nanotubes, the dependence of a nonlinear current on an ac electric field with an inclined-leading-edge width of {Delta}T = 3 Multiplication-Sign 10{sup -11} s and wavelength of {lambda} Almost-Equal-To 1 mm is studied. It is theoretically and numerically shown that the surface current is almost independent of the nanotube radius. In the case of semiconductor zigzag-type nanotubes, the radiation of a two-frequency CO{sub 2} laser with a constant amplitude is considered as an ac electric field. The dependence on the relaxation time in the Boltzmann kinetic equation is studied. The optimal conditions for terahertz-radiation generation are achieved when the relaxation time is 40 fs. It is numerically found that the amplified radiation amplitude behaves as beats.

Sadykov, N. R., E-mail: n.r.sadykov@rambler.ru; Scorkin, N. A.; Akhljustina, E. A. [Snezhinsk Physics and Technology Institute of the National Research Nuclear University 'MEPhI' (Russian Federation)] [Snezhinsk Physics and Technology Institute of the National Research Nuclear University 'MEPhI' (Russian Federation)

2013-09-15T23:59:59.000Z

330

The Relative Effects of Direct and Indirect Actions of Ionizing Radiations on Deoxyribonucleic Acid  

Science Journals Connector (OSTI)

...determined over a range of concentrations...means that over this range of concentration...independent of the dose rate and of the hardness of the radiations within the ranges used and identical...indirect actions of ionizing radiations on deoxyribonucleic...

1958-01-01T23:59:59.000Z

331

Standard Test Method for Measuring Dose for Use in Linear Accelerator Pulsed Radiation Effects Tests  

E-Print Network (OSTI)

1.1 This test method covers a calorimetric measurement of the total dose delivered in a single pulse of electrons from an electron linear accelerator or a flash X-ray machine (FXR, e-beam mode) used as an ionizing source in radiation-effects testing. The test method is designed for use with pulses of electrons in the energy range from 10 to 50 MeV and is only valid for cases in which both the calorimeter and the test specimen to be irradiated are“thin” compared to the range of these electrons in the materials of which they are constructed. 1.2 The procedure described can be used in those cases in which (1) the dose delivered in a single pulse is 5 Gy (matl) (500 rd (matl)) or greater, or (2) multiple pulses of a lower dose can be delivered in a short time compared to the thermal time constant of the calorimeter. Matl refers to the material of the calorimeter. The minimum dose per pulse that can be acceptably monitored depends on the variables of the particular test, including pulse rate, pulse uniformity...

American Society for Testing and Materials. Philadelphia

2011-01-01T23:59:59.000Z

332

Human radiation studies: Remembering the early years. Oral history of Merril Eisenbud, January 26, 1995  

SciTech Connect

Merril Eisenbud was interviewed on January 26, 1995 by representatives of the US DOE Office of Human Radiation Experiments. Following a brief biographical sketch, Mr. Eisenbud relates his remembrances as the AEC`s first industrial hygienist, the setting up of AEC`s Health and Safety Laboratory, monitoring radioactive fallout, and use or exposure of humans to radiation.

NONE

1995-05-01T23:59:59.000Z

333

Chromosome translocations and cosmic sources of ionizing radiation: The NIOSH-NCI airline pilot biomarker study  

Science Journals Connector (OSTI)

...and cosmic sources of ionizing radiation: The NIOSH-NCI airline...are exposed to cosmic ionizing radiation, an efficient inducer...bone marrow absorbed dose in cGy from personal...SD; 46.7 5.3, range 37-55 vs. 45.8...

Lee Yong; Alice Sigurdson; Elizabeth Ward; Martha Waters; Elizabeth Whelan; Martin Petersen; Elaine Ron; Marilyn Ramsey; Parveen Bhatti; and James Tucker

2007-05-01T23:59:59.000Z

334

HRTEM Study of Oxide Nanoparticles in K3-ODS Ferritic Steel Developed for Radiation Tolerance  

SciTech Connect

Crystal and interfacial structures of oxide nanoparticles and radiation damage in 16Cr-4.5Al-0.3Ti-2W-0.37 Y{sub 2}O{sub 3} ODS ferritic steel have been examined using high-resolution transmission electron microscopy (HRTEM) techniques. Oxide nanoparticles with a complex-oxide core and an amorphous shell were frequently observed. The crystal structure of complex-oxide core is identified to be mainly monoclinic Y{sub 4}Al{sub 2}O{sub 9} (YAM) oxide compound. Orientation relationships between the oxide and the matrix are found to be dependent on the particle size. Large particles (> 20 nm) tend to be incoherent and have a spherical shape, whereas small particles (< 10 nm) tend to be coherent or semi-coherent and have a faceted interface. The observations of partially amorphous nanoparticles and multiple crystalline domains formed within a nanoparticle lead us to propose a three-stage mechanism to rationalize the formation of oxide nanoparticles containing core/shell structures in as-fabricated ODS steels. Effects of nanoparticle size and density on cavity formation induced by (Fe{sup 8+} + He{sup +}) dual-beam irradiation are briefly addressed.

Hsiung, L; Fluss, M; Tumey, S; Kuntz, J; El-Dasher, B; Wall, M; Choi, W; Kimura, A; Willaime, F; Serruys, Y

2009-11-02T23:59:59.000Z

335

A study of low Q/sup 2/ radiative Bhabha scattering  

SciTech Connect

This thesis presents a study of electron-positron scattering, via nearly real photon exchange, where in the process one or more high energy photons are produced. The motivations behind the work are twofold. Firstly, the study is a sensitive test of the theory of electron-photon interactions, quantum electrodynamics. A deviation from the theory could indicate that the electron is a composite particle. Secondly, a thorough understanding of this process is necessary for experiments to be done in the near future at the Stanford Linear Collider and the LEP facility at CERN. Calculations for the process to third and fourth order in pertubation theory are described. Methods for simulating the process by a Monte Carlo event generator are given. Results from the calculations are compared to data from the Mark II experiment at the PEP storage ring. The ratio of measured to calculated cross sections are 0.993 /+-/ 0.017 /+-/ 0.015 and 0.99 /+-/ 0.16 /+-/ 0.08 for final states with one and two observed photons respectively, where the first errors are statistical and the second systematic. The excellent agreement verifies the calculations of the fourth order radiative correction. No evidence for electron substructure is observed.

Karlen, D.A.

1988-03-01T23:59:59.000Z

336

NONTHERMAL RADIATION FROM SUPERNOVA REMNANTS: EFFECTS OF MAGNETIC FIELD AMPLIFICATION AND PARTICLE ESCAPE  

SciTech Connect

We explore nonlinear effects of wave-particle interactions on the diffusive shock acceleration (DSA) process in Type Ia-like supernova remnant (SNR) blast waves by implementing phenomenological models for magnetic field amplification (MFA), Alfvénic drift, and particle escape in time-dependent numerical simulations of nonlinear DSA. For typical SNR parameters, the cosmic-ray (CR) protons can be accelerated to PeV energies only if the region of amplified field ahead of the shock is extensive enough to contain the diffusion lengths of the particles of interest. Even with the help of Alfvénic drift, it remains somewhat challenging to construct a nonlinear DSA model for SNRs in which of the order of 10% of the supernova explosion energy is converted into CR energy and the magnetic field is amplified by a factor of 10 or so in the shock precursor, while, at the same time, the energy spectrum of PeV protons is steeper than E {sup –2}. To explore the influence of these physical effects on observed SNR emission, we also compute the resulting radio-to-gamma-ray spectra. Nonthermal emission spectra, especially in X-ray and gamma-ray bands, depend on the time-dependent evolution of the CR injection process, MFA, and particle escape, as well as the shock dynamic evolution. This result comes from the fact that the high-energy end of the CR spectrum is composed of particles that are injected in the very early stages of the blast wave evolution. Thus, it is crucial to better understand the plasma wave-particle interactions associated with collisionless shocks in detailed modeling of nonthermal radiation from SNRs.

Kang, Hyesung [Department of Earth Sciences, Pusan National University, Pusan 609-735 (Korea, Republic of); Jones, T. W. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Edmon, Paul P., E-mail: kang@uju.es.pusan.ac.kr, E-mail: twj@msi.umn.edu, E-mail: pedmon@cfa.harvard.edu [Research Computing, Harvard University, Cambridge, MA 02138 (United States)

2013-11-01T23:59:59.000Z

337

Cancer and non-cancer effects in Japanese atomic bomb survivorsPresented as an invited paper at the 21st LH Gray Conference 'The Radiobiology—Radiation  

Science Journals Connector (OSTI)

The survivors of the atomic bombings in Hiroshima and Nagasaki are a general population of all ages and sexes and, because of the wide and well characterised range of doses received, have been used by many scientific committees (International Commission on Radiological Protection (ICRP), United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), Biological Effects of Ionizing Radiations (BEIR)) as the basis of population cancer risk estimates following radiation exposure. Leukaemia was the first cancer to be associated with atomic bomb radiation exposure, with preliminary indications of an excess among the survivors within the first five years after the bombings. An excess of solid cancers became apparent approximately ten years after radiation exposure. With increasing follow-up, excess risks of most cancer types have been observed, the major exceptions being chronic lymphocytic leukaemia, and pancreatic, prostate and uterine cancer. For most solid cancer sites a linear dose response is observed, although in the latest follow-up of the mortality data there is evidence (p = 0.10) for an upward curvature in the dose response for all solid cancers. The only cancer sites which exhibit (upward) curvature in the dose response are leukaemia, and non-melanoma skin and bone cancer. For leukaemia the dose response is very markedly upward curving, indeed largely describable as a pure quadratic dose response, particularly in the low dose (0–2 Sv) range. Even 55 years after the bombings over 40% of the Life Span Study cohort remain alive, so continued follow-up of this group is vital for completing our understanding of long-term radiation effects in people. In general, the relative risks per unit dose among the Japanese atomic bomb survivors are greater than those among comparable subsets in studies of medically exposed individuals. Cell sterilisation largely accounts for the discrepancy in relative risks between these two populations, although other factors may contribute, such as the generally higher underlying cancer risks in the medical series than in the Japanese atomic bomb survivors. Risks among occupationally exposed groups such as nuclear workforces and underground miners are generally consistent with those observed in the Japanese atomic bomb survivors. In general, consistent patterns of variation of risk with age at exposure are also seen in all studies—risks for all cancer types diminish with increasing age at exposure. There are also excess risks of various types of non-malignant disease in the Japanese atomic bomb survivors, in particular cardiovascular, respiratory and digestive diseases. Indeed, risks are elevated to much the same degree for a number of non-malignant disease endpoints, suggestive of bias. However, in contrast with the cancer data, there is much less consistency in the pattern of risk between the atomic bomb survivors and other exposed groups; for example, radiation-associated respiratory and digestive diseases have not been seen in these other groups. Although cardiovascular risks have been seen elsewhere, particularly in medically exposed groups, in contrast with the cancer data there is much less consistency in risk between studies: risks per unit dose in epidemiological studies vary over at least two orders of magnitude, possibly as a result of confounding factors. In the absence of a convincing mechanistic explanation of epidemiological evidence, at present a cause-and-effect interpretation of the reported statistical associations for cardiovascular disease is unreliable but cannot be excluded. Further epidemiological and biological evidence will allow a firmer conclusion to be drawn.

M P Little

2009-01-01T23:59:59.000Z

338

EFFECTS OF MAGNETIC FIELD AND FAR-ULTRAVIOLET RADIATION ON THE STRUCTURES OF BRIGHT-RIMMED CLOUDS  

SciTech Connect

The bright-rimmed cloud SFO 22 was observed with the 45 m telescope of Nobeyama Radio Observatory in the {sup 12}CO (J = 1-0), {sup 13}CO (J = 1-0), and C{sup 18}O (J = 1-0) lines, where well-developed head-tail structure and small line widths were found. Such features were predicted by radiation-driven implosion models, suggesting that SFO 22 may be in a quasi-stationary equilibrium state. We compare the observed properties with those from numerical models of a photoevaporating cloud, which include effects of magnetic pressure and heating due to strong far-ultraviolet (FUV) radiation from an exciting star. The magnetic pressure may play a more important role in the density structures of bright-rimmed clouds than the thermal pressure that is enhanced by the FUV radiation. The FUV radiation can heat the cloud surface to near 30 K; however, its effect is not enough to reproduce the observed density structure of SFO 22. An initial magnetic field of 5 {mu}G in our numerical models produces the best agreement with the observations, and its direction can affect the structures of bright-rimmed clouds.

Motoyama, Kazutaka [National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430 (Japan)] [National Institute of Informatics, 2-1-2 Hitotsubashi, Chiyoda-ku, Tokyo 101-8430 (Japan); Umemoto, Tomofumi [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 191-8588 (Japan)] [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 191-8588 (Japan); Shang, Hsien; Hasegawa, Tatsuhiko, E-mail: motoyama@nii.ac.jp [Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 106, Taiwan (China)] [Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 106, Taiwan (China)

2013-03-20T23:59:59.000Z

339

Cloud Effects on Radiative Heating Rate Profiles over Darwin using ARM and A-train Radar/Lidar Observations  

SciTech Connect

Observations of clouds from the ground-based U.S. Department of Energy Atmospheric Radiation Measurement program (ARM) and satellite-based A-train are used to compute cloud radiative forcing profiles over the ARM Darwin, Australia site. Cloud properties are obtained from both radar (the ARM Millimeter Cloud Radar (MMCR) and the CloudSat satellite in the A-train) and lidar (the ARM Micropulse lidar (MPL) and the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite in the A-train) observations. Cloud microphysical properties are taken from combined radar and lidar retrievals for ice clouds and radar only or lidar only retrievals for liquid clouds. Large, statistically significant differences of up to 1.43 K/day exist between the mean ARM and A-train net cloud radiative forcing profiles. The majority of the difference in cloud radiative forcing profiles is shown to be due to a large difference in the cloud fraction above 12 km. Above this altitude the A-train cloud fraction is significantly larger because more clouds are detected by CALIPSO than by the ground-based MPL. It is shown that the MPL is unable to observe as many high clouds as CALIPSO due to being more frequently attenuated and a poorer sensitivity even in otherwise clear-sky conditions. After accounting for cloud fraction differences and instrument sampling differences due to viewing platform we determined that differences in cloud radiative forcing due to the retrieved ice cloud properties is relatively small. This study demonstrates that A-train observations are better suited for the calculation cloud radiative forcing profiles. In addition, we find that it is necessary to supplement CloudSat with CALIPSO observations to obtain accurate cloud radiative forcing profiles since a large portion of clouds at Darwin are detected by CALIPSO only.

Thorsen, Tyler J.; Fu, Qiang; Comstock, Jennifer M.

2013-06-11T23:59:59.000Z

340

Nanoscale Engineering Of Radiation Tolerant Silicon Carbide....  

NLE Websites -- All DOE Office Websites (Extended Search)

Engineering Of Radiation Tolerant Silicon Carbide. Nanoscale Engineering Of Radiation Tolerant Silicon Carbide. Abstract: Radiation tolerance is determined by how effectively the...

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Radiation, Infection, and Macrophage Function IV. Effect of Radiation on the Proliferative Abilities of Mononuclear Phagocytes in Tuberculous Lesions of Rabbits  

Science Journals Connector (OSTI)

...likely interpretation would be that radiation reduced MN production in the bone...the auspices of the United States- Japan Cooperative Medical Science Program...of tuberculosis: VOL. 3, 1971 RADIATION, INFECTION, AND MACROPHAGE FUNCTION...

Saroj Chandrasekhar; Kiyoshi Shima; Arthur M. Dannenberg Jr.; Takeshi Kambara; Jacob I. Fabrikant; William G. Roessler

1971-02-01T23:59:59.000Z

342

Studies of Particulates and Structural Transformations in Glass Using Synchrotron Radiation. Final Technical Report  

SciTech Connect

The initial study on nanoparticles of magnetite was carried out in an epoxy matrix. The formation of agglomerates of Fe3O4 nanoparticles was studied by mu-XRF, magnetic, TEM and SEM techniques. Because of the elevated viscosity of epoxy resin and its effect on particle agglomeration, this study was extended using less viscous polyvinyl alcohol and some sol gels as a matrix. Unlike the results found in epoxy resin, spherical agglomerates were found in a PVA matrix even at Fe3O4 concentration of up to 50%.

Thorpe, Arthur

2001-04-13T23:59:59.000Z

343

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

SciTech Connect

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

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

2013-02-01T23:59:59.000Z

344

Mitigation Effect of an FGF-2 Peptide on Acute Gastrointestinal Syndrome After High-Dose Ionizing Radiation  

SciTech Connect

Purpose: Acute gastrointestinal syndrome (AGS) resulting from ionizing radiation causes death within 7 days. Currently, no satisfactory agent exists for mitigation of AGS. A peptide derived from the receptor binding domain of fibroblast growth factor 2 (FGF-P) was synthesized and its mitigation effect on AGS was examined. Methods and Materials: A subtotal body irradiation (sub-TBI) model was created to induce gastrointestinal (GI) death while avoiding bone marrow death. After 10.5 to 16 Gy sub-TBI, mice received an intramuscular injection of FGF-P (10 mg/kg/day) or saline (0.2 ml/day) for 5 days; survival (frequency and duration) was measured. Crypt cells and their proliferation were assessed by hematoxylin, eosin, and BrdU staining. In addition, GI hemoccult score, stool formation, and plasma levels of endotoxin, insulin, amylase, interleukin (IL)-6, keratinocyte-derived chemokine (KC) monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor (TNF)-alpha were evaluated. Results: Treatment with FGF-P rescued a significant fraction of four strains of mice (33-50%) exposed to a lethal dose of sub-TBI. Use of FGF-P improved crypt survival and repopulation and partially preserved or restored GI function. Furthermore, whereas sub-TBI increased plasma endotoxin levels and several pro-inflammation cytokines (IL-6, KC, MCP-1, and TNF-alpha), FGF-P reduced these adverse responses. Conclusions: The study data support pursuing FGF-P as a mitigator for AGS.

Zhang Lurong [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Sun Weimin; Wang Jianjun [Second Military Medical College, Shanghai (China); Zhang Mei; Yang Shanmin [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Tian Yeping [Second Military Medical College, Shanghai (China); Vidyasagar, Sadasivan [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Pena, Louis A. [Brookhaven National Laboratory, Medical Department, Upton, NY (United States); Zhang Kunzhong [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Cao Yongbing [Second Military Medical College, Shanghai (China); Yin Liangjie [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Wang Wei [Department of Surgery, Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian (China); Zhang Lei [Department of Laboratory Medicine, West China Hospital of Sichuan University, Chengdu, Sichuan (China); Schaefer, Katherine L.; Saubermann, Lawrence J. [Department of Medicine, University of Rochester Medical Center, Rochester, NY (United States); Swarts, Steven G.; Fenton, Bruce M.; Keng, Peter C. [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States); Okunieff, Paul, E-mail: Paul_Okunieff@URMC.Rochester.ed [Department of Radiation Oncology, University of Rochester Medical Center, Rochester, NY (United States)

2010-05-01T23:59:59.000Z

345

The effects of emitter-tied field plates on lateral PNP ionizing radiation response  

SciTech Connect

Radiation response comparisons of lateral PNP bipolar technologies reveal that device hardening may be achieved by extending the emitter contact over the active base. The emitter-tied field plate suppresses recombination of carriers with interface traps.

Barnaby, H.J.; Schrimpf, R.D.; Cirba, C.R. [Vanderbilt Univ., Nashville, TN (United States); Pease, R.L. [RLP Research, Inc., Albuquerque, NM (United States); Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States); Kosier, S.L. [VTC Inc., Bloomington, MN (United States)

1998-03-01T23:59:59.000Z

346

Radiation Exposure to Patient and Staff in Hepatic Chemoembolization: Risk Estimation of Cancer and Deterministic Effects  

Science Journals Connector (OSTI)

In order to calculate the organ doses, we used only the dosemeter values measured ... negligible compared to the direct and significantly longer radiation exposure to the liver region. When one wishes to keep the...

Nico Hidajat; Peter Wust; Roland Felix…

347

Stochastic modeling of the cell killing effect for low- and high-LET radiation  

E-Print Network (OSTI)

length distribution, with deterministic RMR models. For low LET radiation and at high dose rates the stochastic survival results agree well with the deterministic survival results. Also the stochastic model allows for non-linearity at low doses due...

Partouche, Julien

2005-02-17T23:59:59.000Z

348

The parametric doppler effect upon oblique radiation incidence in quartz glass  

Science Journals Connector (OSTI)

Frequency and reflection angle of probe radiation from a refractive-index inhomogeneity induced by an intense pumping pulse in quartz glass and moving with a relativistic velocity are calculated. Conditions un...

N. V. Vysotina; N. N. Rosanov; V. B. Shilov

2014-06-01T23:59:59.000Z

349

The Doppler Effect and Form of the Profile of Radiation Spectral Lines  

Science Journals Connector (OSTI)

The form of the profile for spectral lines of radiation is found using the relativistic distribution function (DF) of fluxons on velocities and exact relativistic Doppler formula for frequencies. It is shown t...

M. R. Djumaev

2001-01-01T23:59:59.000Z

350

Effects of coupled atomic states on the resonance scattering of radiation  

E-Print Network (OSTI)

The excitation and decay probabilities for resonance scattering of radiation from an atom with two coupled excited states in an external static field are calculated as a function of time and frequency. Various oscillatory ...

Srivastava, Rajendra P.; Fontana, Peter R.

1974-01-01T23:59:59.000Z

351

Phase II study of radiation therapy combined with weekly nedaplatin in locally advanced uterine cervical carcinoma: Kitasato Gynecologic Radiation Oncology Group (KGROG 0501) - an initial analysis  

Science Journals Connector (OSTI)

...of Medicine, Chiba, Japan, The University of...induced by ionizing radiation (IR) and can be repaired...of the character and radiation survival ratio of cancer...Hemagglutinating Virus of Japan envelope vector (HVJ-E...clonogenic assay to evaluate radiation sensitivity. Furthermore...

Yuzuru Niibe; Shimpei Tsunoda; Toshiko Jobo; Yukihiro Hamada; and Kazushige Hayakawa

2007-05-01T23:59:59.000Z

352

Dosimetric effects of weight loss or gain during volumetric modulated arc therapy and intensity-modulated radiation therapy for prostate cancer  

SciTech Connect

Weight loss or gain during the course of radiation therapy for prostate cancer can alter the planned dose to the target volumes and critical organs. Typically, source-to-surface distance (SSD) measurements are documented by therapists on a weekly basis to ensure that patients' exterior surface and isocenter-to-skin surface distances remain stable. The radiation oncology team then determines whether the patient has undergone a physical change sufficient to require a new treatment plan. The effect of weight change (SSD increase or decrease) on intensity-modulated radiation therapy (IMRT) or volumetric modulated arc therapy (VMAT) dosimetry is not well known, and it is unclear when rescanning or replanning is needed. The purpose of this study was to determine the effects of weight change (SSD increase or decrease) on IMRT or VMAT dose delivery in patients with prostate cancer and to determine the SSD change threshold for replanning. Whether IMRT or VMAT provides better dose stability under weight change conditions was also determined. We generated clinical IMRT and VMAT prostate and seminal vesicle treatment plans for varying SSDs for 10 randomly selected patients with prostate cancer. The differences due to SSD change were quantified by a specific dose change for a specified volume of interest. The target mean dose, decreased or increased by 2.9% per 1-cm SSD decrease or increase in IMRT and by 3.6% in VMAT. If the SSD deviation is more than 1 cm, the radiation oncology team should determine whether to continue treatment without modifications, to adjust monitor units, or to resimulate and replan.

Pair, Matthew L. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Du, Weiliang [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Rojas, Hector D.; Kanke, James E.; McGuire, Sean E.; Lee, Andrew K.; Kuban, Deborah A. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Kudchadker, Rajat J., E-mail: rkudchad@mdanderson.org [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2013-10-01T23:59:59.000Z

353

Shielded coherent synchrotron radiation and its possible effect in the next linear collider  

SciTech Connect

Shielded coherent synchrotron radiation is discussed in two cases: (1) a beam following a curved path in a plane midway between two parallel, perfectly conducting plates, and (2) a beam circulating in a toroidal chamber with resistive walls. Wake fields and the radiated energy are computed with parameters for the high-energy bunch compressor of the Next Linear Collider. 5 refs., 4 figs., 1 tab.

Warnock, R.L.

1991-05-01T23:59:59.000Z

354

DOE Order Self Study Modules - 10 CFR 835 Occupational Radiation Protection  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

10 CFR 835 10 CFR 835 OCCUPATIONAL RADIATION PROTECTION NATIONAL NUCLEAR SECURITY ADMINISTRATION LEARNING AND CAREER DEVELOPMENT DEPARTMENT Change No: 1 10 CFR 835 Level: Familiar Date:11/1/08 1 10/1/08 10 CFR 835 OCCUPATIONAL RADIATION PROTECTION FAMILIAR LEVEL ___________________________________________________________________________ OBJECTIVES Given the familiar level of this module and the resources, you will be able to perform the following: 1. State the scope of 10 CFR 835. 2. Define the following terms. annual limit on intake bioassay contamination area derived air concentration high contamination area radiation weighting factor 3. State the requirements of the general rule. 4. State the radiation protection program requirements. 5. State the requirements of the internal audit.

355

Solar Radiation and Pyranometry Studies for Solar Energy Applications: an Overview of IEA Task IX  

Science Journals Connector (OSTI)

With increased activity in the field of solar energy research and application, there is a need for accurate solar radiation and meteorological data to aid in resource assessment, solar system design evaluation, a...

D. C. McKay

1984-01-01T23:59:59.000Z

356

Study of cloud properties from single-scattering, radiative forcing, and retrieval perspectives  

E-Print Network (OSTI)

This dissertation reports on three different yet related topics in light scattering computation, radiative transfer simulation, and remote sensing implementation, regarding the cloud properties and the retrieval of cloud properties from satellite...

Lee, Yong-Keun

2009-06-02T23:59:59.000Z

357

Coupled forward-adjoint monte carlo simulations of radiative transport for the study of optical probe design in heterogeneous tissues  

E-Print Network (OSTI)

approximation to the radiative transport equation [3, 7, 15,form of the radiative transport equation (RTE) assumed to

Hayakawa, Carole K.; Spanier, Jerome; Venugopalan, Vasan

2007-01-01T23:59:59.000Z

358

Determination of erythema-effective solar radiation in Japan and Germany with a spore monolayer film optimized for the detection of UVB and UVA – results of a field campaign  

Science Journals Connector (OSTI)

...The available physical and biological broadband radiometers designed to determine erythema-effective radiation do not show any response or over/underestimate the biologically effective radiation to a high exte...

Y. Furusawa; L. E. Quintern; H. Holtschmidt…

1998-11-01T23:59:59.000Z

359

The myth of cell phone radiation  

E-Print Network (OSTI)

We discuss the purported link between cell phone radiation and cancer. We show that it is inconsistent with the photoelectric effect, and that epidemiological studies of any link have no scientific basis.

Natarajan, Vasant

2012-01-01T23:59:59.000Z

360

The myth of cell phone radiation  

E-Print Network (OSTI)

We discuss the purported link between cell-phone radiation and cancer. We show that it is inconsistent with the photoelectric effect, and that epidemiological studies of any link have no scientific basis.

Vasant Natarajan

2012-11-22T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Studies on Pentoxifylline and Tocopherol Combination for Radiation-Induced Heart Disease in Rats  

SciTech Connect

Purpose: To investigate whether the application of pentoxifylline (PTX) and tocopherol l (Vit. E) could modify the development of radiation-induced heart disease and downregulate the expression of transforming growth factor (TGF)-{beta}1mRNA in rats. Methods and Materials: A total of 120 Sprague-Dawley rats were separated into four groups: control group, irradiated group, experimental group 1, and experiment group 2. Supplementation was started 3 days before irradiation; in experimental group 1, injection of PTX (15 mg/kg/d) and Vit. E (5.5 mg/kg/d) continued till the 12th week postirradiation, whereas in experimental group 2 it was continued until the 24th week postirradiation. All rats were administrated a single dose of 20 Gy irradiation to the heart except the control group. Histopathologic evaluation was performed at various time points (Days 1, 2, 4, 8, and 12 and 24th week) up to 24 weeks after irradiation. Changes of levels of TGF-{beta}1 mRNA expression were also investigated at the same time points using competitive polymerase chain reaction. Results: Compared with the irradiated group, levels of TGF-{beta}1 mRNA of the rat hearts were relatively low in the two experimental groups on the 12th week postirradiation. In experimental group 1, there was a rebound expression of TGF-{beta}1 mRNA on the 24th week postirradiation, whereas that of the experimental group 2 remained low (p < 0.05). The proportions of collagen fibers of the two experimental groups were lower than that of irradiated group (p < 0.05). A rebound could be observed in the experimental group 1. Conclusion: PTX and Vit. E downregulated the expression of TGF-{beta}1 mRNA. The irradiated rat hearts showed a marked pathologic response to the drugs. The withdrawal of drugs in the 12th week postirradiation could cause rebound effects of the development of fibrosis.

Liu Hui [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Radiotherapy, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Xiong Mai [Department of Cardiac Surgery, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong (China); Xia Yunfei; Cui Nianji; Lu Rubiao [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Radiotherapy, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Deng Ling [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Pathology, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Lin Yuehao [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Clinical Laboratory, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China); Rong Tiehua [State Key Laboratory of Oncology in South China, Guangzhou, Guangdong (China); Department of Thoracic Surgery, Cancer Center, Sun Yat-sen University, Guangzhou, Guangdong (China)], E-mail: esophagus2003@yahoo.com.cn

2009-04-01T23:59:59.000Z

362

Electrochemical Studies of Packed Iron Powder Electrodes: Effects...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Packed Iron Powder Electrodes: Effects of Common Constituents of Natural Waters on Corrosion Electrochemical Studies of Packed Iron Powder Electrodes: Effects of Common...

363

Effects of radiation on NO kinetics in turbulent hydrogen/air diffusion flames  

SciTech Connect

The authors describe a coupled radiation and NO kinetics calculation of turbulent hydrogen/air diffusion flame properties. Transport equations for mass, momentum, mixture fraction, enthalpy (sensible + chemical) including gas band radiation, and NO mass fraction are solved. NO kinetics is described by a one step thermal production mechanism. The local temperature is obtained by solving the enthalpy equation taking radiation loss from H{sub 2}O into consideration. Radiation/turbulence and chemical kinetics/turbulence interactions are treated using a clipped Gaussian probability density function (PDF) for the mixture fraction, and a delta PDF for the enthalpy. The source terms in the enthalpy and mass fraction of NO equations are treated using assumed PDF integration over the mixture fraction space. The results of the simulation are compared with existing measurements of the Emission Indices of NO (EINO) in turbulent H{sub 2}/air diffusion flames. The major conclusion of the paper is that coupled turbulence/radiation interactions should be taken into account while computing the EINO.

Sivathanu, Y.R.; Gore, J.P.; Laurendeau, N.M.

1997-07-01T23:59:59.000Z

364

Japanese Structure Survey of Radiation Oncology in 2005 Based on Institutional Stratification of Patterns of Care Study  

SciTech Connect

Purpose: To evaluate the structure of radiation oncology in Japan in terms of equipment, personnel, patient load, and geographic distribution to identify and improve any deficiencies. Methods and Materials: A questionnaire-based national structure survey was conducted between March 2006 and February 2007 by the Japanese Society of Therapeutic Radiology and Oncology. These data were analyzed in terms of the institutional stratification of the Patterns of Care Study. Results: The total numbers of new cancer patients and total cancer patients (new and repeat) treated with radiotherapy in 2005 were estimated at approximately 162,000 and 198,000, respectively. In actual use were 765 linear accelerators, 11 telecobalt machines, 48 GammaKnife machines, 64 {sup 60}Co remote-controlled after-loading systems, and 119 {sup 192}Ir remote-controlled after-loading systems. The linear accelerator systems used dual-energy function in 498 systems (65%), three-dimensional conformal radiotherapy in 462 (60%), and intensity-modulated radiotherapy in 170 (22%). There were 426 Japanese Society of Therapeutic Radiology and Oncology-certified radiation oncologists, 774 full-time equivalent radiation oncologists, 117 medical physicists, and 1,635 radiation therapists. Geographically, a significant variation was found in the use of radiotherapy, from 0.9 to 2.1 patients/1,000 population. The annual patient load/FTE radiation oncologist was 247, exceeding the Blue Book guidelines level. Patterns of Care Study stratification can clearly discriminate the maturity of structures according to their academic nature and caseload. Conclusions: The Japanese structure has clearly improved during the past 15 years in terms of equipment and its use, although the shortage of manpower and variations in maturity disclosed by this Patterns of Care Study stratification remain problematic. These constitute the targets for nationwide improvement in quality assurance and quality control.

Teshima, Teruki [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Osaka (Japan)], E-mail: teshima@sahs.med.osaka-u.ac.jp; Numasaki, Hodaka [Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Osaka (Japan); Shibuya, Hitoshi [Department of Radiology, Tokyo Dental and Medical University, Tokyo (Japan); Nishio, Masamichi [Department of Radiology, National Hospital Organization Hokkaido Cancer Center, Sapporo, Hokkaido (Japan); Ikeda, Hiroshi [Division of Radiation Oncology, National Cancer Center, Tokyo (Japan); Ito, Hisao [Department of Radiology, Chiba University Graduate School of Medicine, Chiba (Japan); Sekiguchi, Kenji [Department of Radiation Oncology, St. Luke's International Hospital, Tokyo (Japan); Kamikonya, Norihiko [Department of Radiology, Hyogo College of Medicine, Nishinomiya, Hyogo (Japan); Koizumi, Masahiko [Department of Radiological Technology, Fujita Health University School of Health Sciences, Nagoya, Aichi (Japan); Tago, Masao [Department of Radiology, University of Tokyo Hospital, Tokyo (Japan); Nagata, Yasushi [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University Graduate School of Medicine, Kyoto (Japan); Masaki, Hidekazu [Department of Radiology, National Center for Child Health and Development, Tokyo (Japan); Nishimura, Tetsuo [Division of Radiation Oncology, Shizuoka Cancer Center, Shizuoka (Japan); Yamada, Shogo [Tohoku University Hospital Cancer Center, Sendai (Japan)

2008-09-01T23:59:59.000Z

365

Effects of plasma-deposited silicon nitride passivation on the radiation hardness of CMOS integrated circuits  

SciTech Connect

The use of plasma-deposited silicon nitride as a final passivation over metal-gate CMOS integrated circuits degrades the radiation hardness of these devices. The hardness degradation is manifested by increased radiation-induced threshold voltage shifts caused principally by the charging of new interface states and, to a lesser extent, by the trapping of holes created upon exposure to ionizing radiation. The threshold voltage shifts are a strong function of the deposition temperature, and show very little dependence on thickness for films deposited at 300/sup 0/C. There is some correlation between the threshold voltage shifts and the hydrogen content of the PECVD silicon nitride films used as the final passivation layer as a function of deposition temperature. The mechanism by which the hydrogen contained in these films may react with the Si/SiO/sub 2/ interface is not clear at this point.

Clement, J. J.

1980-01-01T23:59:59.000Z

366

Experimental and Modelling Study of the Effect of Diffusional...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Modelling Study of the Effect of Diffusional Limitations on the NH3 SCR Activity Experimental and Modelling Study of the Effect of Diffusional Limitations on the NH3 SCR Activity...

367

DOE Order Self Study Modules - DOE G 441.1-1C Radiation Protection Programs Guide  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

41.1-1C 41.1-1C RADIATION PROTECTION PROGRAMS GUIDE NATIONAL NUCLEAR SECURITY ADMINISTRATION LEARNING AND CAREER DEVELOPMENT DEPARTMENT Change No: 1 DOE G 441.1-1C Level: Familiar Date: 12/1/08 1 DOE G 441.1-1C, RADIATION PROTECTION PROGRAMS GUIDE FAMILIAR LEVEL _________________________________________________________________________ OBJECTIVES Given the familiar level of this module and the resources listed below, you will be able to 1. Match radiation protection-related terms to their definitions; 2. Discuss the elements that should be taken into consideration to determine the likelihood of an individual receiving a dose in excess of a regulatory monitoring threshold; 3. Give three examples of criteria that should trigger a formal as-low-as-is-

368

High-let radiation carcinogenesis  

SciTech Connect

Recent results for neutron radiation-induced tumors are presented to illustrate the complexities of the dose-response curves for high-LET radiation. It is suggested that in order to derive an appropriate model for dose-response curves for the induction of tumors by high-LET radiation it is necessary to take into account dose distribution, cell killing and the susceptibility of the tissue under study. Preliminary results for the induction of Harderian gland tumors in mice exposed to various heavy ion beams are presented. The results suggest that the effectiveness of the heavy ion beams increases with increasing LET. The slopes of the dose-response curves for the different high-LET radiations decrease between 20 and 40 rads and therefore comparisons of the relative effectiveness should be made from data obtained at doses below about 20 to 30 rads.

Fry, R.J.M.; Powers-Risius, P.; Alpen, E.L.; Ainsworth, E.J.; Ullrich, R.L.

1982-01-01T23:59:59.000Z

369

Appendix F: Radiation Appendix F: Radiation F-3  

E-Print Network (OSTI)

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix F: Radiation #12;#12;Appendix F: Radiation F-3 P P P E E E N NN HYDROGEN ATOM DEUTERIUM

Pennycook, Steve

370

Assessing the Effects of Radiation Damage on Ni-base Alloys for the Prometheus Space Reactor System  

SciTech Connect

Ni-base alloys were considered for the Prometheus space reactor pressure vessel with operational parameters of {approx}900 K for 15 years and fluences up to 160 x 10{sup 20} n/cm{sup 2} (E > 0.1 MeV). This paper reviews the effects of irradiation on the behavior of Ni-base alloys and shows that radiation-induced swelling and creep are minor considerations compared to significant embrittlement with neutron ,exposure. While the mechanism responsible for radiation-induced embrittlement is not fully understood, it is likely a combination of helium embrittlement and solute segregation that can be highly dependent on the alloy composition and exposure conditions. Transmutation calculations show that detrimental helium levels would be expected at the end of life for the inner safety rod vessel (thimble) and possibly the outer pressure vessel, primarily from high energy (E > 1 MeV) n,{alpha} reactions with {sup 58}Ni. Helium from {sup 10}B is significant only for the outer vessel due to the proximity of the outer vessel to the Be0 control elements. Recommendations for further assessments of the material behavior and methods to minimize the effects of radiation damage through alloy design are provided.

T. Angeliu

2006-01-19T23:59:59.000Z

371

Assessing the Effects of Radiation Damage on Ni-base Alloys for the Prometheus Space Reactor System  

SciTech Connect

Ni-base alloys were considered for the Prometheus space reactor pressure vessel with operational parameters of {approx}900 K for 15 years and fluences up to 160 x 10{sup 20} n/cm{sup 2} (E > 0.1 MeV). This paper reviews the effects of irradiation on the behavior of Ni-base alloys and shows that radiation-induced swelling and creep are minor considerations compared to significant embrittlement with neutron exposure. While the mechanism responsible for radiation-induced embrittlement is not fully understood, it is likely a combination of helium embrittlement and solute segregation that can be highly dependent on the alloy composition and exposure conditions. Transmutation calculations show that detrimental helium levels would be expected at the end of life for the inner safety rod vessel (thimble) and possibly the outer pressure vessel, primarily from high energy (E > 1 MeV) n,{alpha} reactions with {sup 58}Ni. Helium from {sup 10}B is significant only for the outer vessel due to the proximity of the outer vessel to the BeO control elements. Recommendations for further assessments of the material behavior and methods to minimize the effects of radiation damage through alloy design are provided.

T Angeliu; J Ward; J Witter

2006-04-04T23:59:59.000Z

372

Multisection gas counters for spectral studies of weak pulse x-radiation  

SciTech Connect

This paper describes two multisection gas counters for recording pulse x-radiation. The first design is a set of eight tandem cylindrical gas counters and the second design is a sixsection gas scintillation counter. These detectors measure the free path length of radiation in the gas filling them, form the measurement data using the maximum-liklihood method, and a computer satisfactorily reconstructs the x-ray spectra, when the total number of absorbed photons Np about 10/sup 2/ for one pulse with a duration of less than or equal to 1 usec.

Bogomolov, G.D.; Kravchenko, N.A.; Peskov, V.D.; Podolyak, E.R.

1986-02-01T23:59:59.000Z

373

Estimation of organs doses and radiation-induced secondary cancer risk from scattered photons for conventional radiation therapy of nasopharynx: a Monte Carlo study  

Science Journals Connector (OSTI)

We used Monte Carlo modeling to calculate the organs doses due to out-of field photons during radiation therapy of the nasopharynx.

Asghar Mesbahi; Farshad Seyednejad; Amir Gasemi-Jangjoo

2010-06-01T23:59:59.000Z

374

Effects of High Dietary Iron and Gamma Radiation on Oxidative Stress and Bone  

E-Print Network (OSTI)

. Male Sprague-Dawley rats (15-weeks old, n=32) were randomized to receive an adequate (45 mg Fe/kg diet) or high (650 mg Fe/kg diet) Fe diet for 4 weeks and either 3 Gy (8 fractions, 0.375 Gy each) of 137Cs radiation (?RAD) or sham exposure every other...

Yuen, Evelyn P

2013-04-19T23:59:59.000Z

375

The effects of diet and ionizing radiation on azoxymethane induced colon carcinogenesis  

E-Print Network (OSTI)

cancer, by suppressing apoptosis and upregulating proliferation in colonocytes. Diets contained a combination of fish oil or corn oil and either pectin or cellulose. We exposed 40 male Sprague-Dawley rats to 1 Gy ionizing radiation (1 GeV Fe) 10 d prior...

Mann, John Clifford

2006-10-30T23:59:59.000Z

376

Effects of combined radiofrequency radiation exposure on levels of reactive oxygen species in neuronal cells  

Science Journals Connector (OSTI)

......typical CDMA signal of 837 MHz and a WCDMA signal of 1950 MHz were applied to the RTL...incubator with a humidified atmosphere of 5% CO2. Analysis...exposure to UMTS 1950 MHz radiation and co-exposure...reaction of menadione with plasma thiols: enhancement......

Kyoung Ah Kang; Hyung Chul Lee; Je-Jung Lee; Mi-Na Hong; Myung-Jin Park; Yun-Sil Lee; Hyung-Do Choi; Nam Kim; Young-Gyu Ko; Jae-Seon Lee

2014-03-01T23:59:59.000Z

377

Radiation Dose Measurement by Electron Spin Resonance Studies of Tooth Enamel in Lime and Non-lime Consuming Individuals from the Silchar Region of Northeast India  

Science Journals Connector (OSTI)

......uranium in nuclear workers occupationally exposed to uranium in Rocketdyne, USA (19501994). Apart from the known toxic effects of...radiation exposure on cancer mortality in nuclear workers at Rocketdyne/Atomics Interna- tional. Environ Health Perspect. 108......

Deborshi Bhattacharjee; Alexander I. Ivannikov; Kassym Zhumadilov; Valeriy F. Stepanenko; Kenichi Tanaka; Satoru Endo; Megu Ohtaki; Shin Toyoda; Joyeeta Bhattacharyya; Masaharu Hoshi

2009-11-01T23:59:59.000Z

378

A Mechanism-Based Approach to Predict the Relative Biological Effectiveness of Protons and Carbon Ions in Radiation Therapy  

SciTech Connect

Purpose: The physical and potential biological advantages of proton and carbon ions have not been fully exploited in radiation therapy for the treatment of cancer. In this work, an approach to predict proton and carbon ion relative biological effectiveness (RBE) in a representative spread-out Bragg peak (SOBP) is derived using the repair-misrepair-fixation (RMF) model. Methods and Materials: Formulas linking dose-averaged linear-quadratic parameters to DSB induction and processing are derived from the RMF model. The Monte Carlo Damage Simulation (MCDS) software is used to quantify the effects of radiation quality on the induction of DNA double-strand breaks (DSB). Trends in parameters {alpha} and {beta} for clinically relevant proton and carbon ion kinetic energies are determined. Results: Proton and carbon ion RBE are shown to increase as particle energy, dose, and tissue {alpha}/{beta} ratios decrease. Entrance RBE is {approx}1.0 and {approx}1.3 for protons and carbon ions, respectively. For doses in the range of 0.5 to 10 Gy, proton RBE ranges from 1.02 (proximal edge) to 1.4 (distal edge). Over the same dose range, the RBE for carbon ions ranges from 1.5 on the proximal edge to 6.7 on the distal edge. Conclusions: The proposed approach is advantageous because the RBE for clinically relevant particle distributions is guided by well-established physical and biological (track structure) considerations. The use of an independently tested Monte Carlo model to predict the effects of radiation quality on DSB induction also minimizes the number of ad hoc biological parameters that must be determined to predict RBE. Large variations in predicted RBE across an SOBP may produce undesirable biological hot and cold spots. These results highlight the potential for the optimization of physical dose for a uniform biological effect.

Frese, Malte C. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Department of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); Yu, Victor K. [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Stewart, Robert D. [Department of Radiation Oncology, University of Washington, Seattle, Washington (United States); Carlson, David J., E-mail: david.j.carlson@yale.edu [Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States)

2012-05-01T23:59:59.000Z

379

The effect of different adaptation strengths on image quality and radiation dose using Siemens Care Dose 4D  

Science Journals Connector (OSTI)

......undertaking strategies for CT radiation dose optimisation...supported by the Swedish Radiation Safety Authority (SSI P 1579...4D new technique for radiation dose reduction. SOMATOM...Application Guide. Software Version syngo CT 2005A......

Marcus Söderberg; Mikael Gunnarsson

2010-01-01T23:59:59.000Z

380

Targeted and Nontargeted Effects of Low-Dose Ionizing Radiation on Delayed Genomic Instability in Human Cells  

Science Journals Connector (OSTI)

...humans receive some radiation exposure, mostly...risks associated with radiation exposure come from populations exposed to ionizing radiation, primarily from epidemiologic...However, those doses, in the range of 0.2 to 2.5...

Lei Huang; Perry M. Kim; Jac A. Nickoloff; and William F. Morgan

2007-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Effect of incremental doses of radiation on viability of the microbial population on synthetic operating room gowns.  

Science Journals Connector (OSTI)

...manufacturer and peri- 528 RADIATION DOSE AND MICROBIAL VIABILITY...used to calculate the radiation resistances because...SEM does allow an estimation of the number of cells...ENVIRON. MICROBIOL. RADIATION DOSE AND MICROBIAL VIABILITY...

J L Whitby; D G Storey

1982-03-01T23:59:59.000Z

382

Low Dose Radiation Research Program: William F. Morgan  

NLE Websites -- All DOE Office Websites (Extended Search)

William F. Morgan William F. Morgan Pacific Northwest National Laboratory PO Box 999 Richland, Washington About this Project Projects Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Dose Radiation Research Program A Mechanistic Study of the Radiation Quality Dependence of Bystander Effects in Human Cells. Genetic Factors Affecting Susceptibility to Low-Dose Radiation Mechanisms of Adaptive Responses and Genomic Instability Induced by Low Dose/ Low Dose Rate Radiation Technical Abstracts 2006 Workshop: Using a Low-LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Sowa, M.B., Goetz, W., Baulch, J., and Morgan, W.F. Genetic Factors Affecting Susceptibility to Low-Dose Radiation

383

Radiation Magnetohydrodynamic Simulations of Protostellar Collapse: Non-Ideal Magnetohydrodynamic Effects and Early Formation of Circumstellar Disks  

E-Print Network (OSTI)

The transport of angular momentum by magnetic fields is a crucial physical process in formation and evolution of stars and disks. Because the ionization degree in star forming clouds is extremely low, non-ideal magnetohydrodynamic (MHD) effects such as ambipolar diffusion and Ohmic dissipation work strongly during protostellar collapse. These effects have significant impacts in the early phase of star formation as they redistribute magnetic flux and suppress angular momentum transport by magnetic fields. We perform three-dimensional nested-grid radiation magnetohydrodynamic (RMHD) simulations including Ohmic dissipation and ambipolar diffusion. Without these effects, magnetic fields transport angular momentum so efficiently that no rotationally supported disk is formed even after the second collapse. Ohmic dissipation works only in a relatively high density region within the first core and suppresses angular momentum transport, enabling formation of a very small rotationally supported disk after the second co...

Tomida, Kengo; Machida, Masahiro N

2015-01-01T23:59:59.000Z

384

Study of the spatial coherence of high order harmonic radiation generated from pre-formed plasma plumes  

SciTech Connect

A study of the spatial coherence of the high order harmonic radiation generated by the interaction of 45 fs Ti:sapphire laser beam with carbon (graphite) plasma plume has been carried out using Young's double slit interferometry. It is observed that the spatial coherence varies with harmonic order, laser focal spot size in plasma plume, and peaks at an optimal spot size. It is also observed that the spatial coherence is higher when the laser pulse is focused before the plasma plume than when focused after the plume, and it decreases with increase in the harmonic order. The optimum laser parameters and the focusing conditions to achieve good spatial coherence with high harmonic conversion have been identified, which is desirable for practical applications of the harmonic radiation.

Kumar, M.; Singhal, H.; Chakera, J. A.; Naik, P. A.; Khan, R. A.; Gupta, P. D. [Laser Plasma Division, Raja Ramanna Centre for Advanced Technology, Indore 452 013, M.P. (India)

2013-07-21T23:59:59.000Z

385

Preliminary studies and tests of semiconductors for their use as nuclear radiation detectors  

E-Print Network (OSTI)

of the semiconductors which were used in the tests~ and from Hughes Ines of Culver City, California, who provided a set of diodes of a type that had been sucessfully used as a radiation detector. 1 1 See article by Salzberg and Siegal of Airborne Instru- ments... that each semiconductor junction has a different breakdown point and has a different thermal noise pulse versus temperature characteristic. Silicon diodes were selected for tests because of their low thermal noise char- acteristics. The experimenter...

Willis, Giles Whitehurst

2012-06-07T23:59:59.000Z

386

Numerical and simulation study of terahertz radiation generation by laser pulses propagating in the extraordinary mode in magnetized plasma  

SciTech Connect

A one-dimensional numerical model for studying terahertz radiation generation by intense laser pulses propagating, in the extraordinary mode, through magnetized plasma has been presented. The direction of the static external magnetic field is perpendicular to the polarization as well as propagation direction of the laser pulse. A transverse electromagnetic wave with frequency in the terahertz range is generated due to the presence of the magnetic field. Further, two-dimensional simulations using XOOPIC code show that the THz fields generated in plasma are transmitted into vacuum. The fields obtained via simulation study are found to be compatible with those obtained from the numerical model.

Jha, Pallavi; Kumar Verma, Nirmal [Department of Physics, University of Lucknow, Lucknow-226007 (India)

2014-06-15T23:59:59.000Z

387

L-Boronophenylalanine-Mediated Boron Neutron Capture Therapy for Malignant Glioma Progressing After External Beam Radiation Therapy: A Phase I Study  

SciTech Connect

Purpose: To investigate the safety of boronophenylalanine-mediated boron neutron capture therapy (BNCT) in the treatment of malignant gliomas that progress after surgery and conventional external beam radiation therapy. Methods and Materials: Adult patients who had histologically confirmed malignant glioma that had progressed after surgery and external beam radiotherapy were eligible for this Phase I study, provided that >6 months had elapsed from the last date of radiation therapy. The first 10 patients received a fixed dose, 290 mg/kg, of L-boronophenylalanine-fructose (L-BPA-F) as a 2-hour infusion before neutron irradiation, and the remaining patients were treated with escalating doses of L-BPA-F, either 350 mg/kg, 400 mg/kg, or 450 mg/kg, using 3 patients on each dose level. Adverse effects were assessed using National Cancer Institute Common Toxicity Criteria version 2.0. Results: Twenty-two patients entered the study. Twenty subjects had glioblastoma, and 2 patients had anaplastic astrocytoma, and the median cumulative dose of prior external beam radiotherapy was 59.4 Gy. The maximally tolerated L-BPA-F dose was reached at the 450 mg/kg level, where 4 of 6 patients treated had a grade 3 adverse event. Patients who were given >290 mg/kg of L-BPA-F received a higher estimated average planning target volume dose than those who received 290 mg/kg (median, 36 vs. 31 Gy [W, i.e., a weighted dose]; p = 0.018). The median survival time following BNCT was 7 months. Conclusions: BNCT administered with an L-BPA-F dose of up to 400 mg/kg as a 2-hour infusion is feasible in the treatment of malignant gliomas that recur after conventional radiation therapy.

Kankaanranta, Leena [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Seppaelae, Tiina; Koivunoro, Hanna [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Department of Physics, University of Helsinki, Helsinki (Finland); Boneca Corporation, Helsinki (Finland); Vaelimaeki, Petteri [Department of Physics, University of Helsinki, Helsinki (Finland); Boneca Corporation, Helsinki (Finland); Beule, Annette [HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Collan, Juhani [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Kortesniemi, Mika [HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Uusi-Simola, Jouni [Department of Physics, University of Helsinki, Helsinki (Finland); HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Kotiluoto, Petri; Auterinen, Iiro; Seren, Tom [VTT Technical Research Centre of Finland, Espoo (Finland); Paetau, Anders [Department of Pathology, Helsinki University Central Hospital, Helsinki (Finland); Saarilahti, Kauko [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland); Savolainen, Sauli [Department of Physics, University of Helsinki, Helsinki (Finland); HUS Medical Imaging Center, Helsinki University Central Hospital, Helsinki (Finland); Joensuu, Heikki, E-mail: heikki.joensuu@hus.f [Department of Oncology, Helsinki University Central Hospital, Helsinki (Finland)

2011-06-01T23:59:59.000Z

388

Observations of radiation in the space radiation environment and its effect on commercial off-the-shelf electronics in low-Earth orbit  

Science Journals Connector (OSTI)

...orbits, the space radiation environment is particularly hostile...applications of the space environment: new results and interdisciplinary...approach requires design engineers to have a good knowledge of the environment to which their systems...

2003-01-01T23:59:59.000Z

389

Radiation effects in moist-air systems and the influence of radiolytic product formation on nuclear waste glass corrosion  

SciTech Connect

Ionizing radiation may affect the performance of glass in an unsaturated repository site by interacting with air, water vapor, or liquid water to produce a variety of radiolytic products. Tests were conducted to examine the effects of radiolysis under high gas/liquid ratios. Results indicate that nitrate is the predominant radiolytic product produced following both gamma and alpha radiation exposure, with lesser amounts of nitrite and carboxylic acids. The formation of nitrogen acids during exposure to long-lived, alpha-particle-emitting transuranic elements indicates that these acids may play a role in influencing nuclear waste form reactions in a long-term unsaturated disposal scenario. Experiments were also conducted with samples that simulate the composition of Savannah River Plant nuclear waste glasses. Radiolytic product formation in batch tests (340 m{sup {minus}1}, 90 C) resulted in a small increase in the release rates of many glass components, such as alkali and alkaline earth elements, although silicon and uranium release rates were slightly reduced indicating an overall beneficial effect of radiation on waste form stability. The radiolytic acids increased the rate of ion exchange between the glass and the thin film of condensate, resulting in accelerated corrosion rates for the glass. The paragenetic sequence of alteration phases formed on both the irradiated and nonirradiated glass samples reacted in the vapor hydration tests matches closely with those developed during volcanic glass alteration in naturally occurring saline-alkaline lake systems. This correspondence suggests that the high temperatures used in these tests have not changed the underlying glass reaction mechanism relate to that which controls glass reactions under ambient surficial conditions.

Wronkiewicz, D.J.; Bates, J.K.; Buck, E.C.; Hoh, J.C.; Emery, J.W. [Argonne National Lab., IL (United States). Chemical Technology Div.; Wang, L.M. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Geology

1997-07-01T23:59:59.000Z

390

Radiation and Health Thormod Henriksen  

E-Print Network (OSTI)

of radioactivity from reactor accidents and fallout from nuclear explosions in the atmosphere. These subjects were interest is the effect of small radiation doses, given at a low dose rate. These studies are of importance for environmental problems as well as within cancer treatment. The group have close cooperations with professor

Johansen, Tom Henning

391

Assessment of Uncertainty in Cloud Radiative Effects and Heating Rates through Retrieval Algorithm Differences: Analysis using 3-years of ARM data at Darwin, Australia  

SciTech Connect

Ground-based radar and lidar observations obtained at the Department of Energy’s Atmospheric Radiation Measurement Program’s Tropical Western Pacific site located in Darwin, Australia are used to retrieve ice cloud properties in anvil and cirrus clouds. Cloud microphysical properties derived from four different retrieval algorithms (two radar-lidar and two radar only algorithms) are compared by examining mean profiles and probability density functions of effective radius (Re), ice water content (IWC), extinction, ice number concentration, ice crystal fall speed, and vertical air velocity. Retrieval algorithm uncertainty is quantified using radiative flux closure exercises. The effect of uncertainty in retrieved quantities on the cloud radiative effect and radiative heating rates are presented. Our analysis shows that IWC compares well among algorithms, but Re shows significant discrepancies, which is attributed primarily to assumptions of particle shape. Uncertainty in Re and IWC translates into sometimes-large differences in cloud radiative effect (CRE) though the majority of cases have a CRE difference of roughly 10 W m-2 on average. These differences, which we believe are primarily driven by the uncertainty in Re, can cause up to 2 K/day difference in the radiative heating rates between algorithms.

Comstock, Jennifer M.; Protat, Alain; McFarlane, Sally A.; Delanoe, Julien; Deng, Min

2013-05-22T23:59:59.000Z

392

Effect of gas radiation and property variation on the performance of thermal regenerators  

E-Print Network (OSTI)

with experiments by Larkin et al [18]. The interaction of conduction, convection 12 and radiation in a fully developed laminar flow was investi- gated by Viskanta [19] by solving a non linear integro- differential energy equation. In order to simplify...: Where (3 2) ae = &eA ( I &e I ) +~ Fe' 0 j 18 an = Dn+( I+nl) +I Fn' Oj p 4x4y 4t Here T' refers to the known value of temperature at a time t, while all other values are at unknown values at time t+4t. The mass flow rates F? F, F? and F...

Gadiraju, Srinivasa Varma

2012-06-07T23:59:59.000Z

393

The Effect of Radiative Cooling on the Sunyaev-Zel'dovich Cluster Counts and Angular Power Spectrum: Analytic Treatment  

E-Print Network (OSTI)

Recently, the entropy excess detected in the central cores of groups and clusters has been successfully interpreted as being due to radiative cooling of the hot intragroup/intracluster gas. In such a scenario, the entropy floors $S_{\\rm floor}$ in groups/clusters at any given redshift are completely determined by the conservation of energy. In combination with the equation of hydrostatic equilibrium and the universal density profile for dark matter, this allows us to derive the remaining gas distribution of groups and clusters after the cooled material is removed. Together with the Press-Schechter mass function we are able to evaluate effectively how radiative cooling can modify the predictions of SZ cluster counts and power spectrum. It appears that our analytic results are in good agreement with those found by hydrodynamical simulations. Namely, cooling leads to a moderate decrease of the predicted SZ cluster counts and power spectrum as compared with standard scenario. However, without taking into account energy feedback from star formation which may greatly suppress cooling efficiency, it is still premature to claim that this modification is significant for the cosmological applications of cluster SZ effect.

Yu-Ying Zhang; Xiang-Ping Wu

2002-10-01T23:59:59.000Z

394

Effective spacetime and Hawking radiation from moving domain wall in thin film of 3He-A  

E-Print Network (OSTI)

An event horizon for "relativistic" fermionic quasiparticles can be constructed in a thin film of superfluid 3He-A. The quasiparticles see an effective "gravitational" field which is induced by a topological soliton of the order parameter. Within the soliton the "speed of light" crosses zero and changes sign. When the soliton moves, two planar event horizons (black hole and white hole) appear, with a curvature singularity between them. Aside from the singularity, the effective spacetime is incomplete at future and past boundaries, but the quasiparticles cannot escape there because the nonrelativistic corrections become important as the blueshift grows, yielding "superluminal" trajectories. The question of Hawking radiation from the moving soliton is discussed but not resolved.

T. A. Jacobson; G. E. Volovik

1998-11-04T23:59:59.000Z

395

Gamma Radiation Effects on Physical, Optical, and Structural Properties of Binary As-S glasses  

SciTech Connect

Gamma radiation induces changes in physical, optical, and structural properties in chalcogenide glasses., Previous research has focused on As{sub 2}S{sub 3} and families of glasses containing Ge. For the first time, we present composition and dose dependent data on the As-S binary glass series. Binary As{sub x}S{sub 100-x} (x = 30, 33, 36, 40, and 42) glasses were irradiated with gamma radiation using a {sup 60}Co source at 2.8 Gy/s to accumulated doses of 1, 2, 3, and 4 MGy. The irradiated samples were characterized at each dose level for density, refractive index, x-ray diffraction, and Raman spectrum. These results are compared to those of as-made and 1 year aged samples. We report an initial increase in density followed by a decrease as a function of dose that contradicts the expected compositional dependence of molar volume of these glasses. This unusual behavior is explained based on microvoid formation and nanoscale phase-separation induced by the irradiation in these glasses. XRD, Raman, and EPR data provide supporting evidence, underscoring the importance of optimally- or overly-constrained structures for stability under aging or irradiation.

Sundaram, S. K.; McCloy, John S.; Riley, Brian J.; Murphy, Mark K.; Qiao, Hong (Amy) [Amy; Windisch, Charles F.; Walter, Eric D.; Crum, Jarrod V.; Golovchak, Roman; Shpotyuk, O.

2012-03-01T23:59:59.000Z

396

Simulated Stratospheric Ozone Depletion and Increased Ultraviolet Radiation: Effects on Photocarcinogenesis in Hairless Mice  

Science Journals Connector (OSTI)

...the "sunburn" portion of the solar UVR spectrum (solar flux under those conditions...200 J of erythemally effective energy per sq m, as weighted by a...the actual meter-effective energy (in terms of the efficacy spectrum...

P. Donald Forbes; Ronald E. Davies; Frederick Urbach; Daniel Berger; and Curtis Cole

1982-07-01T23:59:59.000Z

397

Atomic and Molecular Photoelectron and Auger Electron SpectroscopyStudies Using Synchrotron Radiation  

SciTech Connect

Electron spectroscopy, combined with synchrotron radiation, was used to measure the angular distributions of photoelectrons and Auger electrons from atoms and molecules as functions of photon energy. The branching ratios and partial cross sections were a 130 measured in certain cases. By comparison with theoretical calculations, the experimental results are interpreted in terms of the characteristic electronic structure and ionization dynamics of the atomic or molecular sample. The time structure of the synchrotron radiation source was used to record time-of-flight (TOF) spectra o f the ejected electrons. The ''a double-angle-TOF'' method for the measurement of photoelectron angular distributions is discussed. This technique offers the advantages of increased electron collect ion efficiency and the elimination of certain systematic errors. Several results were obtained for Xe using photon energies in the range hv {approx_equal} 60-190 eV, where excitation and ionization of the inner-subshell 4d electrons dominates. The 4d asymmetry parameter {beta} exhibits strong oscillations with energy, in agreement with several theoretical calculations. As predicted, the 5p asymmetry parameter was observed to deviate strongly from that calculated using the independent-electron model, due to intershell correlation with the 4d electrons.

Southworth, Stephen H.

1982-01-01T23:59:59.000Z

398

Solar radiation effects on evaporative losses of floating roof storage tanks  

Science Journals Connector (OSTI)

There are 40 storage tanks in the Khark Island for storing crude oil. Considering the hot summers of the island, light hydrocarbons vaporise and vented to the atmosphere. This process causes environmental pollution and also affects the quality of the crude oil besides the economic detriment. Therefore, crude oil evaporation loss associated with the storage tank is an important issue which should be carefully investigated to identify the potential means of its reduction. The aim of the present work is to determine the evaporative losses from external floating storage tanks and to study the absorptivity effects of their exterior surface paint on the losses due to the solar irradiation. The API standards along with the thermal analysis of the tank have been employed to evaluate the tank temperature variations and the evaporative losses of a typical tank based on the actual ambient conditions of the Khark Island. The results show that the paints with low absorptivity can reduce the evaporative losses significantly. Furthermore, experimental data has been provided to validate the calculated tank temperature variations, and reasonable agreements have been found. [Received: April 10, 2010; Accepted: May 31, 2010

Mahmood Farzaneh-Gord; Amin Nabati; Hamid Niazmand

2011-01-01T23:59:59.000Z

399

Effect of {gamma}-ray radiation on electrical properties of heat-treated Tb{sub x}Sn{sub 1-x}Se single crystals  

SciTech Connect

The effect of {gamma}-ray radiation on the electrical properties of heat-treated Tb{sub 0.01}Sn{sub 0.99}Se (sample 1) and Tb{sub 0.05}Sn{sub 0.95}Se (sample 2) samples is studied. It is found that, as a result of irradiation with {gamma}-ray 1.25-MeV photons, the charge-carrier concentration decreases in the temperature range T = 77-200 K by 17 and 6.3% for samples 1 and 2, respectively. It is assumed that, in the course of irradiation with {gamma}-ray photons, terbium impurity atoms are located between sites of the crystal lattice; in addition, Frenkel defects are formed.

Huseynov, J. I., E-mail: cih_58@mail.ru; Jafarov, T. A. [Azerbaijan State Pedagogical University (Azerbaijan)

2012-04-15T23:59:59.000Z

400

Molecular Pathways: Targeted ?-Particle Radiation Therapy  

Science Journals Connector (OSTI)

...and profibrotic cytokines. Radiation-induced malignancy can...1-5 Gy). Kyoji Furukawa (Radiation Effect Research Foundation, Hiroshima, Japan) reviewed the Japanese atomic...late effects of ionizing radiation exposure at low/moderate...

Kwamena E. Baidoo; Kwon Yong; and Martin W. Brechbiel

2013-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Human radiation studies: Remembering the early years: Oral history of physician James S. Robertson, M.D., Ph.D., conducted January 20, 1995  

SciTech Connect

This report is a transcript of in interview of Dr. James S. Robertson by representatives of the DOE Office of Human Radiation Experiments. Dr. Robertson was chosen for this interview because of his research at Brookhaven National Laboratory, especially on Boron Neutron Capture Therapy (BNCT); his work at the United States Naval Defense Laboratory; and his work at the Atomic Energy Commission. After a brief biographical sketch Dr. Robertson discusses research on human subjects at Berkeley, his contributions to the beginnings of Neutron Capture Therapy at Brookhaven, his participation with the Brookhaven Human Use Committee, his involvement in the study of the effects of Castle Bravo event on the Marshallese, and his work with the Naval Radiological Defense Laboratory.

NONE

1995-09-01T23:59:59.000Z

402

Human radiation studies: Remembering the early years. Oral history of Julie Langham Grilly, February 3, 1995  

SciTech Connect

Julie Langham Grilly was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE) being the widow of Dr. Wright Langham, an investigator of principal interest of the committee. Her extensive experience with research at LANL was also of interest to the committee. Following a brief biographical sketch, Ms. Grilly relates her early postwar experience and her knowledge of Wright Langham`s involvement in animal research at Los Alamos, radiolanthanum tests on monkeys, Eniwetok tissue examinations, research on tritium uptake in humans, plutonium injections, tritium injections, EDTA, and etc. In addition to illuminating her former husband as a researcher and as an individual, she also relates her remembrances of Louis Hempelman, Enrico Fermi, Oppenheimer, Edward Teller, and many others.

NONE

1995-09-01T23:59:59.000Z

403

Experimental setup for studying the effects of alpha particles on zebrafish embryos  

E-Print Network (OSTI)

doses corresponding to the abnormally developed embryos ranged from 0.41 to 2.3 mGy, which response to ionizing radiation have emerged. For example, Bladen et al. [3] studied the DNA damage response to ionizing radiation in these studi

Yu, K.N.

404

A novel approach in electron beam radiation therapy of lips carcinoma: A Monte Carlo study  

SciTech Connect

Purpose: Squamous cell carcinoma (SCC) is commonly treated by electron beam radiotherapy (EBRT) followed by a boost via brachytherapy. Considering the limitations associated with brachytherapy, in this study, a novel boosting technique in EBRT of lip carcinoma using an internal shield as an internal dose enhancer tool (IDET) was evaluated. An IDET is referred to a partially covered internal shield located behind the lip. It was intended to show that while the backscattered electrons are absorbed in the portion covered with a low atomic number material, they will enhance the target dose in the uncovered area. Methods: Monte-Carlo models of 6 and 8 MeV electron beams were developed using BEAMnrc code and were validated against experimental measurements. Using the developed models, dose distributions in a lip phantom were calculated and the effect of an IDET on target dose enhancement was evaluated. Typical lip thicknesses of 1.5 and 2.0 cm were considered. A 5 Multiplication-Sign 5 cm{sup 2} of lead covered by 0.5 cm of polystyrene was used as an internal shield, while a 4 Multiplication-Sign 4 cm{sup 2} uncovered area of the shield was used as the dose enhancer. Results: Using the IDET, the maximum dose enhancement as a percentage of dose at d{sub max} of the unshielded field was 157.6% and 136.1% for 6 and 8 MeV beams, respectively. The best outcome was achieved for lip thickness of 1.5 cm and target thickness of less than 0.8 cm. For lateral dose coverage of planning target volume, the 80% isodose curve at the lip-IDET interface showed a 1.2 cm expansion, compared to the unshielded field. Conclusions: This study showed that a boost concomitant EBRT of lip is possible by modifying an internal shield into an IDET. This boosting method is especially applicable to cases in which brachytherapy faces limitations, such as small thicknesses of lips and targets located at the buccal surface of the lip.

Shokrani, Parvaneh [Medical Physics and Medical Engineering Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan 81746-73461 (Iran, Islamic Republic of); Baradaran-Ghahfarokhi, Milad [Medical Physics and Medical Engineering Department, School of Medicine, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran and Medical Radiation Engineering Department, Faculty of Advanced Sciences and Technologies, Isfahan University, Isfahan 81746-73441 (Iran, Islamic Republic of); Zadeh, Maryam Khorami [Medical Physics Department, School of Medicine, Ahwaz Jundishapour University of Medical Sciences, Ahwaz 15794-61357 (Iran, Islamic Republic of)

2013-04-15T23:59:59.000Z

405

Assessing exposure to radiation  

SciTech Connect

Since the founding of Lawrence Livermore National Laboratory, we have been world leaders in evaluating the risks associated with radiation. Ultrasensitive tools allow us not only to measure radionuclides present in the body but also to reconstruct the radiation dose from past nuclear events and to project the levels of radiation that will still be present in the body for 50 years after the initial intake. A variety of laboratory procedures, including some developed here, give us detailed information on the effects of radiation at the cellular level. Even today, we are re-evaluating the neutron dose resulting from the bombing at Hiroshima. Our dose reconstruction and projection capabilities have also been applied to studies of Nagasaki, Chernobyl, the Mayak industrial complex in the former Soviet Union, the Nevada Test Site, Bikini Atoll, and other sites. We are evaluating the information being collected on individuals currently working with radioactive material at Livermore and elsewhere as well as previously collected data on workers that extends back to the Manhattan Project.

Walter, K.

1997-01-01T23:59:59.000Z

406

Acute Radiation Effects on Cardiac Function Detected by Strain Rate Imaging in Breast Cancer Patients  

SciTech Connect

Purpose: To investigate the occurrence of early radiation-induced changes in regional cardiac function using strain rate imaging (SRI) by tissue Doppler echocardiography. Methods and Materials: We included 20 left-sided and 10 right-sided breast cancer patients receiving radiotherapy (RT) to the breast or chest wall. Standard echocardiography and SRI were performed before RT (baseline), immediately after RT (post-RT), and at 2 months follow-up (FUP) after RT. Regional strain (S) and strain rate (SR) values were obtained from all 18 left ventricular (LV) segments. Data were compared to the regional radiation dose. Results: A reduction in S was observed post-RT and at FUP in left-sided patients (S{sub post-RT}: -17.6 {+-} 1.5%, and S{sub FUP}: -17.4 {+-} 2.3%, vs. S{sub baseline}: -19.5 {+-} 2.1%, p < 0.001) but not in right-sided patients. Within the left-sided patient group, S and SR were significantly reduced after RT in apical LV segments (S{sub post-RT}: -15.3 {+-} 2.5%, and S{sub FUP}: -14.3 {+-} 3.7%, vs. S{sub baseline}: -19.3 {+-} 3.0%, p < 0.01; and SR{sub post-RT}: -1.06 {+-} 0.15 s {sup -1}, and SR{sub FUP}: -1.16 {+-} 0.28 s {sup -1}, vs. SR{sub baseline}: -1.29 {+-} 0.27s {sup -1}, p = 0.01), but not in mid- or basal segments. Furthermore, we observed that segments exposed to more than 3 Gy showed a significant decrease in S after RT (S{sub post-RT}: -16.1 {+-} 1.6%, and S{sub FUP}: -15.8 {+-} 3.4%, vs. S{sub baseline}: -18.9 {+-} 2.6%, p < 0.001). This could not be observed in segments receiving less than 3 Gy. Conclusions: SRI shows a dose-related regional decrease in myocardial function after RT. It might be a useful tool in the evaluation of modern RT techniques, with respect to cardiac toxicity.

Erven, Katrien, E-mail: Katrien.erven@uzleuven.b [Department of Radiotherapy, University Hospital Gasthuisberg, Leuven (Belgium); Jurcut, Ruxandra [Department of Cardiology, Institute of Emergency for Cardiovascular Diseases, UMF Carol Davila, Bucharest (Romania); Weltens, Caroline [Department of Radiotherapy, University Hospital Gasthuisberg, Leuven (Belgium); Giusca, Sorin [Department of Cardiology, Institute of Emergency for Cardiovascular Diseases, UMF Carol Davila, Bucharest (Romania); Ector, Joris [Department of Cardiology, University Hospital Gasthuisberg, Leuven (Belgium); Wildiers, Hans [Department of Medical Oncology, University Hospital Gasthuisberg, Leuven (Belgium); Van den Bogaert, Walter [Department of Radiotherapy, University Hospital Gasthuisberg, Leuven (Belgium); Voigt, Jens-Uwe [Department of Cardiology, University Hospital Gasthuisberg, Leuven (Belgium)

2011-04-01T23:59:59.000Z

407

Dental and maxillofacial abnormalities in long-term survivors of childhood cancer: effects of treatment with chemotherapy and radiation to the head and neck  

SciTech Connect

Sixty-eight long-term survivors of childhood cancer were evaluated for dental and maxillofacial abnormalities. Forty-five patients had received maxillofacial radiation for lymphoma, leukemia, rhabdomyosarcoma, and miscellaneous tumors. Forty-three of the 45 patients and the remaining 23 who had not received maxillofacial radiation also received chemotherapy. Dental and maxillofacial abnormalities were detected in 37 of the 45 (82%) radiated patients. Dental abnormalities comprised foreshortening and blunting of roots, incomplete calcification, premature closure of apices, delayed or arrested tooth development, and caries. Maxillofacial abnormalities comprised trismus, abnormal occlusal relationships, and facial deformities. The abnormalities were more severe in those patients who received radiation at an earlier age and at higher dosages. Possible chemotherapeutic effects in five of 23 patients who received treatment for tumors located outside the head and neck region comprised acquired amelogenesis imperfecta, microdontia of bicuspid teeth, and a tendency toward thinning of roots with an enlarged pulp chamber. Dental and maxillofacial abnormalities should be recognized as a major consequence of maxillofacial radiation in long-term survivors of childhood cancer, and attempts to minimize or eliminate such sequelae should involve an effective interaction between radiation therapists, and medical and dental oncologists.

Jaffe, N.; Toth, B.B.; Hoar, R.E.; Ried, H.L.; Sullivan, M.P.; McNeese, M.D.

1984-06-01T23:59:59.000Z

408

Appendix G: Radiation HYDROGEN ATOM  

E-Print Network (OSTI)

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix G: Radiation #12;#12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

409

Appendix A: Radiation HYDROGEN ATOM  

E-Print Network (OSTI)

. People are exposed to naturally occurring radiation constantly. For example, cosmic radiation; radon effects on the environment and biological systems. Radiation comes from natural and human-made sourcesAppendix A: Radiation #12;P P P E E E N NN HYDROGEN ATOM DEUTERIUM ATOM TRITIUM ATOM HYDROGEN

Pennycook, Steve

410

Human Biodistribution and Radiation Dosimetry of the Tachykinin NK1 Antagonist Radioligand  

E-Print Network (OSTI)

with PET. The aims of this study were to estimate the radiation safety profile and relative risks of [18F wall, kidneys, and thyroid had the highest radiation-absorbed doses. Biexponential fitting of mean: Insofar as effective dose is an accurate measure of radiation risk, all 3 methods of analysis provided

Shen, Jun

411

Impact of Radiation Biology on Fundamental Insights in Biology  

DOE R&D Accomplishments (OSTI)

Research supported by OHER [Office of Health and Environmental Research] and its predecessors has as one of its major goals an understanding of the effects of radiation at low doses and dose rates on biological systems, so as to predict their effects on humans. It is not possible to measure such effects directly. They must be predicted from basic knowledge on how radiation affects cellular components such as DNA and membranes and how cells react to such changes. What is the probability of radiation producing human mutations and what are the probabilities of radiation producing cancer? The end results of such studies are radiation exposure standards for workers and for the general population. An extension of these goals is setting standards for exposure to chemicals involved in various energy technologies. This latter problem is much more difficult because chemical dosimetry is a primitive state compared to radiation dosimetry.

Setlow, Richard B.

1982-07-27T23:59:59.000Z

412

Preservation of food by ionizing radiation  

SciTech Connect

This study is presented in three volumes. Vol. I: Presents a concise description of the philosophy of radiation, protection for people working with irradiation processes, including problems associated with the design and operation of a large facility and solutions to problems encountered. Radiation dosimetry and radiolytic effects in foods are also presented. Vol. II: Effects of radiation on bacteria and viruses are discussed as well as the lethal effect on microorganisms and insects. Also presented are the effects of irradiated food on packaging materials. Vol. III: The effects of radurization on meats, poultry, fish, shellfish, fruits, vegetables, and spices. Also included are the effects of irradiation for the use of shelf-life extension.

Josephson, E.S.; Peterson, M.S.

1983-01-01T23:59:59.000Z

413

Alpha Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Basics of Radiation Basics of Radiation Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Basics of Radiation Characteristics of Alpha Radiation 1. Alpha radiation is not able to penetrate skin. 2. Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds. 3. A variety of instruments have been designed to measure alpha radiation. Special training in use of these instruments is essential for making accurate measurements. 4. A civil defense instrument (CD V-700) cannot detect the presence of radioactive materials that produce alpha radiation unless the radioactive materials also produce beta and/or gamma radiation.

414

Los Alamos provides HOPE for radiation belt storm probes  

NLE Websites -- All DOE Office Websites (Extended Search)

HOPE for radiation belt storm probes HOPE for radiation belt storm probes Los Alamos provides HOPE for radiation belt storm probes The HOPE analyzer is one of a suite of instruments that was successfully launched as part of the Radiation Belt Storm Probe mission. August 30, 2012 Artist's rendering showing two spacecraft representing the not-yet-designed Radiation Belt Storm Probes that will study the sun and its effects on Earth. PHOTO CREDIT: Johns Hopkins University Applied Physics Laboratory Artist's rendering showing two spacecraft representing the not-yet-designed Radiation Belt Storm Probes that will study the sun and its effects on Earth. PHOTO CREDIT: Johns Hopkins University Applied Physics Laboratory Contact James E. Rickman Communications Office (505) 665-9203 Email "Today we are boldly going where no spacecraft ever wants to go."

415

Radioactivity and Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radioactivity and Radiation Radioactivity and Radiation Uranium and Its Compounds line line What is Uranium? Chemical Forms of Uranium Properties of Uranium Compounds Radioactivity and Radiation Uranium Health Effects Radioactivity and Radiation Discussion of radioactivity and radiation, uranium and radioactivity, radiological health risks of uranium isotopes and decay products. Radioactivity Radioactivity is the term used to describe the natural process by which some atoms spontaneously disintegrate, emitting both particles and energy as they transform into different, more stable atoms. This process, also called radioactive decay, occurs because unstable isotopes tend to transform into a more stable state. Radioactivity is measured in terms of disintegrations, or decays, per unit time. Common units of radioactivity

416

Radiation therapy for esophageal cancer: results of the patterns of Care Study in Japan 1995–1997  

Science Journals Connector (OSTI)

To report the characteristics and treatment process of esophageal cancer patients treated with radiation therapy (RT) in Japan.

Masahiro Kenjo; Masahiko Oguchi; Kotaro Gomi; Takashi Yamashita; Takashi Uno…

2005-06-01T23:59:59.000Z

417

The effect of thymosin on the survival of CBA/J mice exposed to lethal and acute doses of ionizing radiation  

E-Print Network (OSTI)

THE EFFECT OF THYMOSIN ON THE SURVIVAL OF CBA/J MICE EXPOSED TO LETHAL AND ACUTE DOSES OF IONIZING RADIATION A Thesis ROGER LYNN HUCHTON Submitted to the Graduate College of Texas A&M Unrversrty in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 1978 Major Subject: Biophysrcs THE EFFECT OF THYMQSIN ON THE SURVIVAL OF CBA/J MICE EXPOSED TO LETHAL AND ACUTE DOSES OF IONIZING RADIATION A Thesis by ROGER LYNN HUCHTQN Approved as to style and content by...

Huchton, Roger Lynn

1978-01-01T23:59:59.000Z

418

Quantitative cone-beam CT imaging in radiation therapy using planning CT as a prior: First patient studies  

SciTech Connect

Purpose: Quantitative cone-beam CT (CBCT) imaging is on increasing demand for high-performance image guided radiation therapy (IGRT). However, the current CBCT has poor image qualities mainly due to scatter contamination. Its current clinical application is therefore limited to patient setup based on only bony structures. To improve CBCT imaging for quantitative use, we recently proposed a correction method using planning CT (pCT) as the prior knowledge. Promising phantom results have been obtained on a tabletop CBCT system, using a correction scheme with rigid registration and without iterations. More challenges arise in clinical implementations of our method, especially because patients have large organ deformation in different scans. In this paper, we propose an improved framework to extend our method from bench to bedside by including several new components. Methods: The basic principle of our correction algorithm is to estimate the primary signals of CBCT projections via forward projection on the pCT image, and then to obtain the low-frequency errors in CBCT raw projections by subtracting the estimated primary signals and low-pass filtering. We improve the algorithm by using deformable registration to minimize the geometry difference between the pCT and the CBCT images. Since the registration performance relies on the accuracy of the CBCT image, we design an optional iterative scheme to update the CBCT image used in the registration. Large correction errors result from the mismatched objects in the pCT and the CBCT scans. Another optional step of gas pocket and couch matching is added into the framework to reduce these effects. Results: The proposed method is evaluated on four prostate patients, of which two cases are presented in detail to investigate the method performance for a large variety of patient geometry in clinical practice. The first patient has small anatomical changes from the planning to the treatment room. Our algorithm works well even without the optional iterations and the gas pocket and couch matching. The image correction on the second patient is more challenging due to the effects of gas pockets and attenuating couch. The improved framework with all new components is used to fully evaluate the correction performance. The enhanced image quality has been evaluated using mean CT number and spatial nonuniformity (SNU) error as well as contrast improvement factor. If the pCT image is considered as the ground truth, on the four patients, the overall mean CT number error is reduced from over 300 HU to below 16 HU in the selected regions of interest (ROIs), and the SNU error is suppressed from over 18% to below 2%. The average soft-tissue contrast is improved by an average factor of 2.6. Conclusions: We further improve our pCT-based CBCT correction algorithm for clinical use. Superior correction performance has been demonstrated on four patient studies. By providing quantitative CBCT images, our approach significantly increases the accuracy of advanced CBCT-based clinical applications for IGRT.

Niu Tianye; Al-Basheer, Ahmad; Zhu Lei [Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Georgia Radiation Therapy Center, Department of Radiology, Georgia Health Sciences University, Augusta, Georgia 30912 (United States); Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

2012-04-15T23:59:59.000Z

419

Estimation of tumour dose enhancement due to gold nanoparticles during typical radiation treatments: a preliminary Monte Carlo study  

Science Journals Connector (OSTI)

A recent mice study demonstrated that gold nanoparticles could be safely administered and used to enhance the tumour dose during radiation therapy. The use of gold nanoparticles seems more promising than earlier methods because of the high atomic number of gold and because nanoparticles can more easily penetrate the tumour vasculature. However, to date, possible dose enhancement due to the use of gold nanoparticles has not been well quantified, especially for common radiation treatment situations. Therefore, the current preliminary study estimated this dose enhancement by Monte Carlo calculations for several phantom test cases representing radiation treatments with the following modalities: 140 kVp x-rays, 4 and 6 MV photon beams, and 192Ir gamma rays. The current study considered three levels of gold concentration within the tumour, two of which are based on the aforementioned mice study, and assumed either no gold or a single gold concentration level outside the tumour. The dose enhancement over the tumour volume considered for the 140 kVp x-ray case can be at least a factor of 2 at an achievable gold concentration of 7 mg Au/g tumour assuming no gold outside the tumour. The tumour dose enhancement for the cases involving the 4 and 6 MV photon beams based on the same assumption ranged from about 1% to 7%, depending on the amount of gold within the tumour and photon beam qualities. For the 192Ir cases, the dose enhancement within the tumour region ranged from 5% to 31%, depending on radial distance and gold concentration level within the tumour. For the 7 mg Au/g tumour cases, the loading of gold into surrounding normal tissue at 2 mg Au/g resulted in an increase in the normal tissue dose, up to 30%, negligible, and about 2% for the 140 kVp x-rays, 6 MV photon beam, and 192Ir gamma rays, respectively, while the magnitude of dose enhancement within the tumour was essentially unchanged.

Sang Hyun Cho

2005-01-01T23:59:59.000Z

420

The effect of ionizing radiation on dielectric properties of bovine achilles tendon collagen in the temperature range of thermal denaturation  

Science Journals Connector (OSTI)

The effect of ?-irradiation, with doses from 102?2×103 kGy, on the dielectric properties of solid-state collagen was studied. The temperature dependence of the constants ?? and ??' revealed a decrease in the dena...

F. Jaroszyk; E. Marzec

1994-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "radiative effects study" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

The effects of radiative transfer in maintaining the Indian summer monsoon  

SciTech Connect

Atmospheric radiative transfer is an important thermodynamic forcing for the Indian summer monsoon. The monsoon is a component of a larger scale circulation system the principal components of which are the Hadley cell and the Walker Circulation. The Hadley cell is a thermally direct circulation that transports heat toward the poles. In the northern hemispheric summer, the ascending branch of the Hadley cell moves northward, due to heating of the land masses. This ascending branch of the Hadley cell is referred to as the Intertropical Convergence Zone (ITCZ). The return branch of the Hadley cell is characterized by southwesterly surface winds. At the surface, the ITCZ is marked by convergence of southwesterly surface winds from the south and northeasterly surface winds from the north. As the ITCZ moves northward, the southern extent of the northerly surface winds also moves northward, and southerly surface winds from the south side of the ITCZ also move northward. The surface convergence at the ITCZ is a driving mechanism for the summer monsoon circulation. The northward drift of the Hadley cell in the northern summer ITCZ is the deep convection over the warm pool of water in the western tropical Pacific ocean, located at about 160E. The latent heating in the deep convection drives another direct circulation, known as the Walker Circulation. The upper branch of the Walker Circulation over south Asia is easterly winds created by the deep convection in the western tropical Pacific. Convective activity over the Indian peninsula interacts with the Walker Circulation, creating a jet structure over the western part of India and the eastern Arabian Sea. This structure is known as the Tropical Easterly Jet (TEJ). Secondary circulations associated with the Indian convection also help to maintain the baroclinicity, which is essential to the development of monsoon depression, the maintenance of the monsoon trough, and the circulation and hydrology of the region in general.

Leach, M.J.; Raman, S. [North Carolina State Univ., Raleigh, NC (United States)

1995-04-01T23:59:59.000Z

422

Twenty-channel bolometer array for studying impurity radiation and transport in the TCS field-reversed configuration  

SciTech Connect

A bolometer array diagnostic has been developed for the University of Washington Translation, Confinement, and Sustainment (TCS) field-reversed configuration (FRC) experiment in order to measure radially resolved total radiated power per unit length of the FRC. This will provide radiation energy loss information, useful in power balance and impurity studies. The 20-element photodiode bolometer will be mounted at the midplane of the TCS cylindrical vacuum chamber to view the rotating magnetic field (RMF) generated FRC plasma. Key features of this new bolometer array are (1) extensive electrical shielding against the RMF, (2) robust electrical isolation, (3) trans-impedance amplifiers using a microcoax interface at the array and a fiber optic interface to the screen room, and (4) a custom glass-on-metal socket for the 20-element photodiode chip to ensure high vacuum compatibility. The bolometer array can be retracted behind a gate valve using a stepper motor to protect it during vacuum chamber bakeout. The slit assembly housing is interchangeable to provide flexibility for the viewing sightlines.

Kostora, M. R.; Hsu, S. C.; Wurden, G. A. [Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2006-10-15T23:59:59.000Z

423

Study of anticipated impact on DOE programs from proposed reductions to the external occupational radiation exposure limit  

SciTech Connect

A study of the impact of reducing the occupational radiation exposure limit from 5 rem/yr to 2.5, 1.0 and 0.5 rem/yr, respectively produced the following conclusions: reduction of the occupational exposure limit would result in significant increase in total accumulated exposure to the current radiation worker population and could require an increase in the work force; important programs would have to be abandoned at a planned exposure limit of 0.5 rem/yr; some engineering technology is not sufficiently developed to design or operate at the 0.5 rem/yr limit; even a factor of 2 reduction (2.5 rem/yr) would significantly increase costs and would result in an increase in total exposure to the work force; in addition to a significant one-time initial capital cost resulting from a 0.5 rem/yr limit, there would be a significant increase in annual costs; the major emphasis in controlling occupational exposure should be on further reduction of total man-rem; and current standards are used only as a limit. For example, 97% of the employees receive less than 0.5 rem/yr.

None

1981-02-01T23:59:59.000Z

424

Limits to the Aerosol Indirect Radiative Effect Derived from Observations of Ship Tracks  

E-Print Network (OSTI)

reflectivities. #12;3 In recent years, simulations of the aerosol indirect effect in general circulation models in satellite imagery data. Images at 3.7 µm are used in a semi-automated procedure for identifying polluted concentrations of cloud condensation nuclei (CCN) and more cloud droplets. Because droplet formation is rapid

425

Limits to the Aerosol Indirect Radiative Effect Derived from Observations of Ship Tracks  

Science Journals Connector (OSTI)

One-kilometer Advanced Very High Resolution Radiometer (AVHRR) observations of the effects of ships on low-level clouds off the west coast of the United States are used to derive limits for the degree to which clouds might be altered by increases ...

James A. Coakley Jr.; Christopher D. Walsh

2002-02-01T23:59:59.000Z

426

Canonical rotation variables and non-Hamiltonian forces: solar radiation pressure effects on asteroid rotation  

Science Journals Connector (OSTI)

......the effects by absorbed solar photons on the rotation...drawn. At last, if the solar photons are not absorbed...induced by inelastic energy dissipation for subkilometre...specular reflection of solar photons on Eros' surface...Research Council of Norway, projects 153382 and 170870. REFERENCES......

E. Mysen

2006-11-01T23:59:59.000Z

427

Predicting solar radiation fluxes for solar energy system applications  

Science Journals Connector (OSTI)

The mean daily global solar radiation flux is influenced by astronomical, climatological, geographical, geometrical, meteorological, and physical parameters. This paper deals with the study of the effects of i...

M. H. Saffaripour; M. A. Mehrabian…

2013-07-01T23:59:59.000Z

428

Influence of compensator thickness, field size, and off-axis distance on the effective attenuation coefficient of a cerrobend compensator for intensity-modulated radiation therapy  

SciTech Connect

Intensity-modulated radiation therapy (IMRT) can be performed by using compensators. To make a compensator for an IMRT practice, it is required to calculate the effective attenuation coefficient (?{sub eff}) of its material, which is affected by various factors. We studied the effect of the variation of the most important factors on the calculation of the ?{sub eff} of the cerrobend compensator for 6-MV photon beams, including the field size, compensator thickness, and off-axis distance. Experimental measurements were carried out at 100 cm source-to-surface distance and 10 cm depth for the 6-MV photon beams of an Elekta linac using various field size, compensator thickness, and off-axis settings. The field sizes investigated ranged from 4 × 4 to 25 × 25 cm{sup 2} and the cerrobend compensator thicknesses from 0.5–6 cm. For a fixed compensator thickness, variation of the ?{sub eff} with the field size ranged from 3.7–6.8%, with the highest value attributed to the largest compensator thickness. At the reference field size of 10 × 10 cm{sup 2}, the ?{sub eff} varied by 16.5% when the compensator thickness was increased from 0.5–6 cm. However, the variation of the ?{sub eff} with the off-axis distance was only 0.99% at this field size, whereas for the largest field size, it was more significant. Our results indicated that the compensator thickness and field size have the most significant effect on the calculation of the compensator ?{sub eff} for the 6-MV photon beam. Therefore, it is recommended to consider these parameters when calculating the compensator thickness for an IMRT practice designed for these beams. The off-axis distance had a significant effect on the calculation of the ?{sub eff} only for the largest field size. Hence, it is recommended to consider the effect of this parameter only for field sizes larger than 25 × 25 cm{sup 2}.

Haghparast, Abbas [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Islamic Republic of Iran (Iran, Islamic Republic of); Eivazi, Mohammad Taghi [Department of Medical Physics, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Islamic Republic of Iran (Iran, Islamic Republic of)

2013-04-01T23:59:59.000Z

429

Dose-Rate Dependence of High-Dose Health Effects in Humans from Photon Radiation with Application to Radiological Terrorism  

SciTech Connect

In 1981, as part of a symposium entitled ''The Control of Exposure of the Public to Ionizing Radiation in the Event of Accident or Attack,'' Lushbaugh, H?bner, and Fry published a paper examining ''radiation tolerance'' of various human health endpoints as a function of dose rate. This paper may not have received the notice it warrants. The health endpoints examined by Lushbaugh et al. were the lethal dose that will kill 50% of people within 60 days of exposure without medical care (LD50/60); severe bone marrow damage in healthy men; severe bone marrow damage in leukemia patients; temporary sterility (azoospermia); reduced male fertility; and late effects such as cancer. Their analysis was grounded in extensive clinical experience and anchored to a few selected data points, and based on the 1968 dose-rate dependence theory of J.L. Bateman. The Lushbaugh et al. paper did not give predictive equations for the relationships, although they were implied in the text, and the relationships were presented in a non-intuitive way. This work derives the parameters needed in Bateman's equation for each health endpoint, tabulates the results, and plots them in a more conventional manner on logarithmic scales. The results give a quantitative indication of how the human organism can tolerate more radiation dose when it is delivered at lower dose rates. For example, the LD50/60 increases from about 3 grays (300 rads) when given at very high dose rates to over 10 grays (1,000 rads) when given at much lower dose rates over periods of several months. The latter figure is borne out by the case of an individual who survived for at least 19 years after receiving doses in the range of 9 to 17 grays (900-1700 rads) over 106 days. The Lushbaugh et al. work shows the importance of sheltering when confronted with long-term exposure to radiological contamination such as would be expected from a radiological dispersion event, reactor accident, or ground-level nuclear explosion.

Strom, Daniel J.

2005-01-14T23:59:59.000Z

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THE EARTH TIDE EFFECTS ON PETROLEUM RESERVOIRS Preliminary Study  

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THE EARTH TIDE EFFECTS ON PETROLEUM RESERVOIRS Preliminary Study A THESIS SUBMITTED ON THE STRESS-STRAIN THEORY AND THE EARTH TIDE MECHANISM 4 2.1 Stress-Strain Theory 4 2.2 General Information on Tides 14 3. THE EFFECTS OF EARTH TIDES ON OPEN WELL-AQUIFER SYSTEMS: STATE OF THE ART 22 3.1 Static

Stanford University

431

Decay channels of core-excited H2S studied by synchrotron-radiation-excited photoelectron spectroscopy  

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The 2p(3a1) to 6a1 and 3b2 photoexcitation resonance of H2S has been studied using synchrotron-radiation-excited photoelectron spectroscopy. The overall shape of the measured photoelectron spectrum of H2S is found to be in close resemblance with the normal Auger-electron spectrum of HCl. The spectrum is assumed to result mainly from the Auger decay in the excited HS molecule taking place after the molecular dissociation of the excited H2S molecule. The finding is compared with the results of multiconfiguration self-consistent-field calculations [A.N. de Brito and H. Agren, following paper, Phys. Rev. A 45, 7953 (1992)].

H. Aksela; S. Aksela; A. Naves de Brito; G. M. Bancroft; K. H. Tan

1992-06-01T23:59:59.000Z

432

Study on Conducted Interference and Radiated Interference of Buck-Boost Converter in Electric Automobile  

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Buck-boost converter is an important component of electric automobile, it is an important interference source in electric automobile, the study of the interference source is ... of buck-boost converter is simplif...

Jian Wang; Youqun Zhao; Liguo Zang; Wei Wang

2013-01-01T23:59:59.000Z

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Assessment of the Effect of Air Pollution Controls on Trends in Shortwave Radiation over the United States from 1995 through 2010 from Multiple Observation Networks  

SciTech Connect

Long term datasets of total (all-sky) and clear-sky downwelling shortwave (SW) radiation, cloud cover fraction (cloudiness) and aerosol optical depth (AOD) are analyzed together with aerosol concentration from several networks (e.g. SURFRAD, CASTNET, IMPROVE and ARM) in the United States (US). Seven states with varying climatology are selected to better understand the effect of aerosols and clouds on SW radiation. This analysis aims to test the hypothesis that the reductions in anthropogenic aerosol burden resulting from substantial reductions in emissions of sulfur dioxide and nitrogen oxides over the past 15 years across the US has caused an increase in surface SW radiation. We show that the total and clear-sky downwelling SW radiation from seven sites have increasing trends except Penn State which shows no tendency in clear-sky SW radiation. After investigating several confounding factors, the causes can be due to the geography of the site, aerosol distribution, heavy air traffic and increasing cloudiness. Moreover, we assess the relationship between total column AOD with surface aerosol concentration to test our hypothesis. In our findings, the trends of clear-sky SW radiation, AOD, and aerosol concentration from the sites in eastern US agree well with our hypothesis. However, the sites in western US demonstrate increasing AOD associated with mostly increasing trends in surface aerosol concentration. At these sites, the changes in aerosol burden and/or direct aerosol effects alone cannot explain the observed changes in SW radiation, but other factors need to be considered such as cloudiness, aerosol vertical profiles and elevated plumes.

Gan, Chuen-Meei; Pleim, Jonathan; Mathur, Rohit; Hogrefe, Christian; Long, Charles N.; Xing, Jia; Roselle, Shawn; Wei, Chao

2014-02-14T23:59:59.000Z

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Patterns of Radiotherapy Practice for Pancreatic Cancer in Japan: Results of the Japanese Radiation Oncology Study Group (JROSG) Survey  

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Purpose To determine the patterns of radiotherapy practice for pancreatic cancer in Japan. Methods and Materials A questionnaire-based national survey of radiotherapy for pancreatic cancer treated between 2000 and 2006 was conducted by the Japanese Radiation Oncology Study Group (JROSG). Detailed information on 870 patients from 34 radiation oncology institutions was accumulated. Results The median age of all patients was 64 years (range, 36–88), and 80.2% of the patients had good performance status. More than 85% of patients had clinical Stage T3-T4 disease, and 68.9% of patients had unresectable disease at diagnosis. Concerning radiotherapy (RT), 49.8% of patients were treated with radical external beam RT (EBRT) (median dose, 50.4 Gy), 44.4% of patients were treated with intraoperative RT (median dose, 25 Gy) with or without EBRT (median dose, 45 Gy), and 5.9% of patients were treated with postoperative radiotherapy (median dose, 50 Gy). The treatment field consisted of the primary tumor (bed) only in 55.6% of the patients. Computed tomography-based treatment planning and conformal RT was used in 93.1% and 83.1% of the patients treated with EBRT, respectively. Chemotherapy was used for 691 patients (79.4%; before RT for 66 patients; during RT for 531; and after RT for 364). Gemcitabine was the most frequently used drug, followed by 5-fluorouracil. Conclusion This study describes the general patterns of RT practice for pancreatic cancer in Japan. Most patients had advanced unresectable disease, and radical EBRT, as well as intraoperative RT with or without EBRT, was frequently used. Chemotherapy with gemcitabine was commonly used in conjunction with RT during the survey period.

Kazuhiko Ogawa; Yoshinori Ito; Katsuyuki Karasawa; Yoshihiro Ogawa; Hiroshi Onishi; Tomoko Kazumoto; Keiko Shibuya; Hitoshi Shibuya; Yoshishige Okuno; Shigeo Nishino; Etsuyo Ogo; Nobue Uchida; Kumiko Karasawa; Kenji Nemoto; Yasumasa Nishimura

2010-01-01T23:59:59.000Z

435

Patterns of Radiotherapy Practice for Pancreatic Cancer in Japan: Results of the Japanese Radiation Oncology Study Group (JROSG) Survey  

SciTech Connect

Purpose: To determine the patterns of radiotherapy practice for pancreatic cancer in Japan. Methods and Materials: A questionnaire-based national survey of radiotherapy for pancreatic cancer treated between 2000 and 2006 was conducted by the Japanese Radiation Oncology Study Group (JROSG). Detailed information on 870 patients from 34 radiation oncology institutions was accumulated. Results: The median age of all patients was 64 years (range, 36-88), and 80.2% of the patients had good performance status. More than 85% of patients had clinical Stage T3-T4 disease, and 68.9% of patients had unresectable disease at diagnosis. Concerning radiotherapy (RT), 49.8% of patients were treated with radical external beam RT (EBRT) (median dose, 50.4 Gy), 44.4% of patients were treated with intraoperative RT (median dose, 25 Gy) with or without EBRT (median dose, 45 Gy), and 5.9% of patients were treated with postoperative radiotherapy (median dose, 50 Gy). The treatment field consisted of the primary tumor (bed) only in 55.6% of the patients. Computed tomography-based treatment planning and conformal RT was used in 93.1% and 83.1% of the patients treated with EBRT, respectively. Chemotherapy was used for 691 patients (79.4%; before RT for 66 patients; during RT for 531; and after RT for 364). Gemcitabine was the most frequently used drug, followed by 5-fluorouracil. Conclusion: This study describes the general patterns of RT practice for pancreatic cancer in Japan. Most patients had advanced unresectable disease, and radical EBRT, as well as intraoperative RT with or without EBRT, was frequently used. Chemotherapy with gemcitabine was commonly used in conjunction with RT during the survey period.

Ogawa, Kazuhiko, E-mail: kogawa@med.u-ryukyu.ac.j [Department of Radiology, University of the Ryukyus, Okinawa (Japan); Ito, Yoshinori [Department of Radiation Oncology, National Cancer Center, Tokyo (Japan); Karasawa, Katsuyuki [Department of Radiation Oncology, Tokyo Metropolitan Komagome Hospital, Tokyo (Japan); Ogawa, Yoshihiro [Department of Radiation Oncology, Tohoku University, Sendai (Japan); Onishi, Hiroshi [Department of Radiology, Yamanashi University, Yamanashi (Japan); Kazumoto, Tomoko [Department of Radiation Oncology, Saitama Cancer Center, Saitama (Japan); Shibuya, Keiko [Department of Radiation Oncology and Image-Applied Therapy, Kyoto University, Kyoto (Japan); Shibuya, Hitoshi [Department of Radiology, Tokyo Medical and Dental University, Tokyo (Japan); Okuno, Yoshishige [Department of Radiation Oncology, Kobe City Medical Center General Hospital, Kobe (Japan); Nishino, Shigeo [Department of Radiation Oncology, Sapporo Kosei General Hospital, Sapporo (Japan); Ogo, Etsuyo [Department of Radiology, Kurume University, Kurume (Japan); Uchida, Nobue [Department of Radiation Oncology, Shimane Medical University, Shimane (Japan); Karasawa, Kumiko [Department of Radiation Oncology, Juntendo University, Tokyo (Japan); Nemoto, Kenji [Department of Radiation Oncology, Yamagata University, Yamagata (Japan); Nishimura, Yasumasa [Department of Radiation Oncology, Kinki University School of Medicine, Osaka (Japan)

2010-07-01T23:59:59.000Z

436

Low dose radiation combines with the Src oncoprotein to transform  

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radiation combines with the Src oncoprotein to transform radiation combines with the Src oncoprotein to transform pre-malignant human breast cells Paul Yaswen Lawrence Berkeley National Laboratory Abstract Goal: Determine whether low dose radiation exerts persistent epigenetic effects that promote malignancy. Background and Significance: Some persistent carcinogenic effects of radiation may not be traceable to specific DNA sequence alterations and may not be linearly related to dose. Through the biochemical initiation of positive feedback loops, ionization-induced events may have heritable non-linear effects on cellular behavior. Inflammatory responses involving the transcription factor NFκB may be subject to such effects. Increased NFκB activity has been strongly linked to carcinogenesis in a number of published in vitro and in vivo studies (reviewed in [1]). Since radiation

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Effect of Field Size and Length of Plantar Spur on Treatment Outcome in Radiation Therapy of Plantar Fasciitis: The Bigger the Better?  

SciTech Connect

Purpose: Radiation therapy is well established in the treatment of painful plantar fasciitis or heel spur. A retrospective analysis was conducted to investigate the effect of field definition on treatment outcome and to determine the impact of factors potentially involved. Methods and Materials: A review of treatment data of 250 patients (285 heels) with a mean follow-up time of 11 months showed that complete symptom remission occurred in 38%, partial remission in 32%, and no change in 19% (11% were lost to follow-up). Variables such as radiologic evidence of plantar spurs, their length, radiation dose, field size, age, sex, and onset of pain before administration of radiation therapy were investigated in univariate and multivariate regression analyses. Results: Treatment response depended upon age >53 years, length of heel spur ?6.5 mm (or no radiologic evidence of a heel spur), and onset of pain <12 months before radiation therapy. Patients with these clinical prerequisites stood a 93% chance of clinical response. Without these prerequisites, only 49% showed any impact. No influence of field size on treatment outcome became evident. Conclusion: Patients with short plantar heel spurs benefit from radiation therapy equally well as patients without any radiologic evidence. Moreover, smaller field sizes have the same positive effect as commonly used large field definitions covering the entire calcaneal bone. This leads to a recommendation of a considerable reduction of field size in future clinical practice.

Hermann, Robert Michael, E-mail: hermann@strahlentherapie-westerstede.com [Zentrum für Strahlentherapie und Radioonkologie, Bremen/Westerstede (Germany); Abteilung Strahlentherapie und Spezielle Onkologie, Medizinische Hochschule Hannover (Germany); Meyer, Andreas [Abteilung Strahlentherapie und Spezielle Onkologie, Medizinische Hochschule Hannover (Germany); Gemeinschaftspraxis für Strahlentherapie Hildesheim/Goslar (Germany); Becker, Alexandra [Zentrum für Strahlentherapie und Radioonkologie, Bremen/Westerstede (Germany); Schneider, Michael [Orthopaedic Centre for Musculoskeletal Research, University of Würzburg (Germany); Reible, Michael; Carl, Ulrich Martin [Zentrum für Strahlentherapie und Radioonkologie, Bremen/Westerstede (Germany); Christiansen, Hans [Abteilung Strahlentherapie und Spezielle Onkologie, Medizinische Hochschule Hannover (Germany); Nitsche, Mirko [Zentrum für Strahlentherapie und Radioonkologie, Bremen/Westerstede (Germany); Klinik für Strahlentherapie, Karl-Lennert-Krebscentrum, Universität Kiel (Germany)

2013-12-01T23:59:59.000Z

438

856 IEEE TRANSACTIONS ON SYSTEMS, MAN, AND CYBERNETICS--PART C: APPLICATIONS AND REVIEWS, VOL. 38, NO. 6, NOVEMBER 2008 Designing Effective Alarms for Radiation Detection  

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to the occurrence of nuisance alarms based on naturally occurring radioactive material and the low base rate of nu Naturally occurring radioactive material. p(false alarm) Probability of a false alarm. p(hit) Probability, NO. 6, NOVEMBER 2008 Designing Effective Alarms for Radiation Detection in Homeland Security

Parasuraman, Raja

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