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1

Regulation Of Nf=kb And Mnsod In Low Dose Radiation Induced Adaptive Protection Of Mouse And Human Skin Cells  

Science Conference Proceedings (OSTI)

A sampling of publications resulting from this grant is provided. One is on the subject of NF-κB-Mediated HER2 Overexpression in Radiation-Adaptive Resistance. Another is on NF-κB-mediated adaptive resistance to ionizing radiation.

Jian Li

2012-11-07T23:59:59.000Z

2

Low Dose Radiation-Induced Epigenetic Alterations Found in Agouti...  

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Low Dose Radiation-Induced Epigenetic Alterations Found in Agouti Mouse Model Autumn Bernal Autumn Bernal Randy Jirtle Randy Jirtle In a paper published in The FASEB Journal, Low...

3

Low dose ionizing radiation induces tumor growth promoting factors in  

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ionizing radiation induces tumor growth promoting factors in ionizing radiation induces tumor growth promoting factors in stress-induced premature senescent fibroblasts David Boothman University of Texas Southwestern Medical Center at Dallas Abstract Recent evidence suggest that the causes of cancer development are not limited to mutations within cancer cells, but also involve in alterations of cancer microenvironment. Senescent cells are irreversibly growth arrested, but remain metabolically active. Senescent cells, especially senescent fibroblasts in the stroma may provide a beneficial environment for tumor growth through secretion of certain factors. Accumulation of senescent cells in the stroma of patients repeatedly exposed to low doses of IR or low dose rates of IR, could be an important factor, causing alteration of the microenvironment that ultimately benefits tumor

4

Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Non-Protein Thiols and Vitamin E.  

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Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Non-Protein Thiols and Vitamin E. J.S. Murley 1 , Y. Kataoka 1 , W.F. Morgan 2 , and D.J. Grdina 1 . The University of Chicago, Chicago, IL 1 , The University of Maryland Medical School, Baltimore, MD 2 Induced or delayed radioprotection is a novel phenomenon that shares many similarities with the low dose radiation-induced radiobiological phenomenon referred to as the adaptive response. Induced or delayed radioprotection is defined as an enhancement in the radiation resistance of cells at long times following their exposure to non-protein thiols (NPT) such as WR1065, the free thiol form of amifostine. This effect is the result of the induction of a cascade of intracellular

5

Low Dose Radiation Research Program: Low Dose Ionizing Radiation-Induced  

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Low Dose Ionizing Radiation-Induced Effects in Irradiated and Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Authors: B.E. Lehnert, R. Cary, D. Gadbois, and G. Gupta. Institutions: Bioscience Division, Los Alamos National Laboratory. The scientific literature presents a confusing picture concerning health risks due to low dose ionizing radiation (LDIR), e.g., <1-10 cGy. Some effects of LDIR such as enhanced rates of cell proliferation and the induction of radioadaptation may be benign under some circumstances. Other evidence suggests LDIR can be hazardous and that a threshold for potentially detrimental responses, e.g., increases in intracellular reactive oxygen species (ROS), increases in sister chromatid exchanges (SCE), alterations in gene or protein expression profiles, and increased

6

Low Dose Radiation Research Program: Frequencies of Radiation-Induced  

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Frequencies of Radiation-Induced Chromosome Interchanges and Frequencies of Radiation-Induced Chromosome Interchanges and Randomness of Chromosome Territory Locations Relative to One Another. Authors: RK Sachs,§ MN Cornforth,‡ KM Greulich-Bode,* L Hlatky, and DJ Brenner|| Institutions: §Department of Mathematics, University of California, ‡University of Texas Medical Branch, *Department of Skin Carcinogenesis, German Cancer Research Center DFCI, Harvard Medical School, ||Center for Radiological Research, Columbia University. Leukemogenesis, and perhaps carcinogenesis in general, often involves specific chromosome translocations. Radiation-induced chromosome translocation frequencies are strongly influenced by how close participating chromosomes are to one another in an interphase cell nucleus. We sought to determine whether chromosomes in human peripheral blood

7

Analysis of low dose radiation induced epigenetic modifications...  

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levels ofbiological organization when organisms are exposed to low doses (<0.1Gy) of irradiation.Recent work in determining the exact effects of low dose radiation have shown that...

8

LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES  

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LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES Daila S. Gridley 1,2 , Asma Rizvi 2 , Xian Luo 1 , Adeola Y. Makinde 2 , Steve Rightnar 1 , Jian Tian 1 , Melba L. Andres 1 , James M. Slater 1 , and Michael J. Pecaut 1,2 Departments of 1 Radiation Medicine and 2 Biochemistry & Microbiology Loma Linda University and Medical Center, Loma Linda, CA 92354 USA Health risks due to protracted low dose irradiation remain unclear. This project investigates T helper (Th) lymphocyte function and the cellular milieu in which they reside under conditions of low dose, low- linear energy transfer (LET) radiation exposure. The Th cells are important because they secrete cytokines essential for generating optimal immune defenses against tumor, virus-infected, and other

9

Low Dose Radiation Research Program: Radiation-Induced Nuclear Factor kB  

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Radiation-Induced Nuclear Factor kB mediates survival advantage by Radiation-Induced Nuclear Factor kB mediates survival advantage by Telomerase Activation. Authors: Natarajan M.,1 Mohan S.,2 Pandeswara, S.L.,1 and Herman T.S.1 Institutions: Departments of 1Radiation Oncology and 2Pathology, The University of Texas Health Science Center, San Antonio, Texas Activation of NF-kB in response to low doses of ionizing radiation was first shown in our laboratory. Although studies have shown that NF-kB plays an important role in anti-apoptotic function, little has been done to understand the molecular link between the activation of NF-kB and cellular outcome such as enhanced cell survival after low dose low-linear transfer (LET) radiation. Because upregulation of telomerase activity is associated with longevity and allows cells to escape from senescence, we hypothesize

10

Estimation of radiation-induced cancer from three-dimensional dose distributions: Concept of organ equivalent dose  

SciTech Connect

Purpose: Estimates of secondary cancer risk after radiotherapy are becoming more important for comparative treatment planning. Modern treatment planning systems provide accurate three-dimensional dose distributions for each individual patient. These data open up new possibilities for more precise estimates of secondary cancer incidence rates in the irradiated organs. We report a new method to estimate organ-specific radiation-induced cancer incidence rates. The concept of an organ equivalent dose (OED) for radiation-induced cancer assumes that any two dose distributions in an organ are equivalent if they cause the same radiation-induced cancer incidence. Methods and Materials: The two operational parameters of the OED concept are the organ-specific cancer incidence rate at low doses, which is taken from the data of the atomic bomb survivors, and cell sterilization at higher doses. The effect of cell sterilization in various organs was estimated by analyzing the secondary cancer incidence data of patients with Hodgkin's disease who were treated with radiotherapy in between 1962 and 1993. The radiotherapy plans used at the time the patients had been treated were reconstructed on a fully segmented whole body CT scan. The dose distributions were calculated in individual organs for which cancer incidence data were available. The model parameter that described cell sterilization was obtained by analyzing the dose and cancer incidence rates for the individual organs. Results: We found organ-specific cell radiosensitivities that varied from 0.017 for the mouth and pharynx up to 1.592 for the bladder. Using the two model parameters (organ-specific cancer incidence rate and the parameter characterizing cell sterilization), the OED concept can be applied to any three-dimensional dose distribution to analyze cancer incidence. Conclusion: We believe that the concept of OED presented in this investigation represents a first step in assessing the potential risk of secondary cancer induction after the clinical application of radiotherapy.

Schneider, Uwe [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland)]. E-mail: uwe.schneider@psi.ch; Zwahlen, Daniel [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland); Ross, Dieter [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland); Kaser-Hotz, Barbara [Division of Diagnostic Imaging and Radio-Oncology, Vetsuisse Faculty, University of Zuerich, Zurich (Switzerland)

2005-04-01T23:59:59.000Z

11

The Circadian Rhythm, A Continuous Transcription-Translation Feedback Loop, Contributes to Low-Dose Radiation-Induced Radioadaptive Response  

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The Circadian Rhythm, A Continuous Transcription-Translation Feedback Loop, Contributes to Low-Dose Radiation-Induced Radioadaptive Response Aris Alexandrou and Jian Jian Li Department of Radiation Oncology, the University of California Davis, Sacramento, California, 95817 The initiation of the circadian rhythm field occurred when the Takahashi group defined a mutation in the mouse gene "Clock" and cloned the circadian locomotor output cycles kaput (Clock) in the mid- 1990's (1-3). Currently more than a dozen clock genes have been identified (3-4). Disruptions in the circadian rhythm via changes in environmental conditions, such as, diet, temperature, and night/day hours lead to the pathogenesis of a multitude of diseases, such as, cancer, diabetes mellitus,

12

Dose Constraints to Prevent Radiation-Induced Brachial Plexopathy in Patients Treated for Lung Cancer  

Science Conference Proceedings (OSTI)

Purpose: As the recommended radiation dose for non-small-cell lung cancer (NSCLC) increases, meeting dose constraints for critical structures like the brachial plexus becomes increasingly challenging, particularly for tumors in the superior sulcus. In this retrospective analysis, we compared dose-volume histogram information with the incidence of plexopathy to establish the maximum dose tolerated by the brachial plexus. Methods and Materials: We identified 90 patients with NSCLC treated with definitive chemoradiation from March 2007 through September 2010, who had received >55 Gy to the brachial plexus. We used a multiatlas segmentation method combined with deformable image registration to delineate the brachial plexus on the original planning CT scans and scored plexopathy according to Common Terminology Criteria for Adverse Events version 4.03. Results: Median radiation dose to the brachial plexus was 70 Gy (range, 56-87.5 Gy; 1.5-2.5 Gy/fraction). At a median follow-up time of 14.0 months, 14 patients (16%) had brachial plexopathy (8 patients [9%] had Grade 1, and 6 patients [7%] had Grade {>=}2); median time to symptom onset was 6.5 months (range, 1.4-37.4 months). On multivariate analysis, receipt of a median brachial plexus dose of >69 Gy (odds ratio [OR] 10.091; 95% confidence interval [CI], 1.512-67.331; p = 0.005), a maximum dose of >75 Gy to 2 cm{sup 3} of the brachial plexus (OR, 4.909; 95% CI, 0.966-24.952; p = 0.038), and the presence of plexopathy before irradiation (OR, 4.722; 95% CI, 1.267-17.606; p = 0.021) were independent predictors of brachial plexopathy. Conclusions: For lung cancers near the apical region, brachial plexopathy is a major concern for high-dose radiation therapy. We developed a computer-assisted image segmentation method that allows us to rapidly and consistently contour the brachial plexus and establish the dose limits to minimize the risk of brachial plexopathy. Our results could be used as a guideline in future prospective trials with high-dose radiation therapy for unresectable lung cancer.

Amini, Arya [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); University of California Irvine School of Medicine, Irvine, California (United States); Yang Jinzhong; Williamson, Ryan [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); McBurney, Michelle L. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Erasmus, Jeremy [Department of Diagnostic Imaging, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Allen, Pamela K.; Karhade, Mandar; Komaki, Ritsuko; Liao, Zhongxing; Gomez, Daniel; Cox, James [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Dong, Lei [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Welsh, James, E-mail: jwelsh@mdanderson.org [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States)

2012-03-01T23:59:59.000Z

13

Mechanisms of Low Dose Radiation-induced T helper Cell Function  

SciTech Connect

Exposure to radiation above levels normally encountered on Earth can occur during wartime, accidents such as those at Three Mile Island and Chernobyl, and detonation of dirty bombs by terrorists. Relatively high levels of radiation exposure can also occur in certain occupations (low-level waste sites, nuclear power plants, nuclear medicine facilities, airline industry, and space agencies). Depression or dysfunction of the highly radiosensitive cells of the immune system can lead to serious consequences, including increased risk for infections, cancer, hypersensitivity reactions, poor wound healing, and other pathologies. The focus of this research was on the T helper (Th) subset of lymphocytes that secrete cytokines (proteins), and thus control many actions and interactions of other cell types that make up what is collectively known as the immune system. The Department of Energy (DOE) Low Dose Radiation Program is concerned with mechanisms altered by exposure to high energy photons (x- and gamma-rays), protons and electrons. This study compared, for the first time, the low-dose effects of two of these radiation forms, photons and protons, on the response of Th cells, as well as other cell types with which they communicate. The research provided insights regarding gene expression patterns and capacity to secrete potent immunostimulatory and immunosuppressive cytokines, some of which are implicated in pathophysiological processes. Furthermore, the photon versus proton comparison was important not only to healthy individuals who may be exposed, but also to patients undergoing radiotherapy, since many medical centers in the United States, as well as worldwide, are now building proton accelerators. The overall hypothesis of this study was that whole-body exposure to low-dose photons (gamma-rays) will alter CD4+ Th cell function. We further proposed that exposure to low-dose proton radiation will induce a different pattern of gene and functional changes compared to photons. Over the course of this research, tissues other than spleens were archived and with funding obtained from other sources, including the Department of Radiation Medicine at the Loma Linda University Medical Center, some additional assays were performed. Furthermore, groups of additional mice were included that were pre-exposed to low-dose photons before irradiating with acute photons, protons, and simulated solar particle event (SPE) protons. Hence, the original support together with the additional funding for our research led to generation of much valuable information that was originally not anticipated. Some of the data has already resulted in published articles, manuscripts in review, and a number of presentations at scientific conferences and workshops. Difficulties in reliable and reproducible quantification of secreted cytokines using multi-plex technology delayed completion of this study for a period of time. However, final analyses of the remaining data are currently being performed and should result in additional publications and presentations in the near future. Some of the most notable conclusions, thus far, are briefly summarized below: - Distribution of leukocytes were dependent upon cell type, radiation quality, body compartment analyzed, and time after exposure. Low-dose protons tended to have less effect on numbers of major leukocyte populations and T cell subsets compared to low-dose photons. - The patterns of gene and cytokine expression in CD4+ T cells after protracted low-dose irradiation were significantly modified and highly dependent upon the total dose and time after exposure. - Patterns of gene and cytokine expression differed substantially among groups exposed to low-dose photons versus low-dose protons; differences were also noted among groups exposed to much higher doses of photons, protons, and simulated SPE protons. - Some measurements indicated that exposure to low-dose photon radiation, especially 0.01 Gy, significantly normalized at least some adverse effects of simulated SPE protons, thereby suggesting that this l

Gridley, Daila S.

2008-10-31T23:59:59.000Z

14

Radiation-Induced Rib Fractures After Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors and Dose-Volume Relationship  

SciTech Connect

Purpose: The purpose of this study was to clarify the incidence, the clinical risk factors, and the dose-volume relationship of radiation-induced rib fracture (RIRF) after hypofractionated stereotactic body radiation therapy (SBRT). Methods and Materials: One hundred sixteen patients treated with SBRT for primary or metastatic lung cancer at our institution, with at least 6 months of follow-up and no previous overlapping radiation exposure, were included in this study. To determine the clinical risk factors associated with RIRF, correlations between the incidence of RIRF and the variables, including age, sex, diagnosis, gross tumor volume diameter, rib-tumor distance, and use of steroid administration, were analyzed. Dose-volume histogram analysis was also conducted. Regarding the maximum dose, V10, V20, V30, and V40 of the rib, and the incidences of RIRF were compared between the two groups divided by the cutoff value determined by the receiver operating characteristic curves. Results: One hundred sixteen patients and 374 ribs met the inclusion criteria. Among the 116 patients, 28 patients (46 ribs) experienced RIRF. The estimated incidence of rib fracture was 37.7% at 3 years. Limited distance from the rib to the tumor (<2.0 cm) was the only significant risk factor for RIRF (p = 0.0001). Among the dosimetric parameters used for receiver operating characteristic analysis, the maximum dose showed the highest area under the curve. The 3-year estimated risk of RIRF and the determined cutoff value were 45.8% vs. 1.4% (maximum dose, {>=}42.4 Gy or less), 51.6% vs. 2.0% (V40, {>=}0.29 cm{sup 3} or less), 45.8% vs. 2.2% (V30, {>=}1.35 cm{sup 3} or less), 42.0% vs. 8.5% (V20, {>=}3.62 cm{sup 3} or less), or 25.9% vs. 10.5% (V10, {>=}5.03 cm{sup 3} or less). Conclusions: The incidence of RIRF after hypofractionated SBRT is relatively high. The maximum dose and high-dose volume are strongly correlated with RIRF.

Asai, Kaori [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Shioyama, Yoshiyuki, E-mail: shioyama@radiol.med.kyushu-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Nonoshita, Takeshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yoshitake, Tadamasa [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Ohnishi, Kayoko [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan)] [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan); Terashima, Kotaro; Matsumoto, Keiji [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Hirata, Hideki [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)

2012-11-01T23:59:59.000Z

15

Radiation-induced angiosarcoma  

E-Print Network (OSTI)

1a Figure 1b Figure 1. Radiation-induced angiosarcoma in afollowing completion of radiation therapy. Figure 2a Figurecell histiocytosis after radiation for breast carcinoma: can

Anzalone, C Lane; Cohen, Philip R; Diwan, Abdul H; Prieto, Victor G

2013-01-01T23:59:59.000Z

16

Molecular Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation  

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Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation Colette A. Sacksteder § , DJ Black ‡ , Heather Smallwood § , David G. Camp II † , and Thomas C. Squier § § Cell Biology and Biochemistry; † Biological Sciences Division Pacific Northwest National Laboratory, Richland WA 99352 ‡ School of Biological Sciences, University of Missouri, Kansas City MO 64110 The goal of this research is to identify the molecular mechanisms by which cells adapt to low dose radiation exposure. Previously we have shown a radiation dependent increase of Calmodulin (CaM) in RAW 264.7 macrophages (RAW). Therefore we hypothesize that CaM and associated signaling complexes are sensors of low-dose radiation, resulting in alterations in energy metabolism and gene expression. The ultimate experimental goal

17

Mechanism underlying mTOR-associated Protection in Low Dose Radiation...  

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low-dose radiation-induced adaptive resistance. Oncogene 27: 6738-6748. 2. Gwinn DM, Shackelford DB, Egan DF, Mihaylova MM, Mery A, Vasquez DS, Turk BE, and Shaw RJ. (2008). AMPK...

18

Profiling of MnSOD Interaction Proteins in Low-Dose Radiation...  

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Proteins in Low-Dose Radiation Induced Adaptive Response Angela Eldridge 1 , Ming Fan 1 , Demet Candas 1 , Brett Chromy, and Jian Jian Li 1 1 Department of Radiation...

19

Low Dose Radiation Research Program: Adaptive Response of Mouse Skin  

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Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Ionizing Radiation: Induction of NF-κB, MnSOD, 14-3-3ζ and Cyclin B1 Authors: Jian Jian Li, Kazi M. Ahmed, Ming Fan, Shaozhong Dong, Douglas R. Spitz, and Cheng-Rong Yu Institutions: Division of Molecular Radiobiology, Purdue University School of Health Sciences, West Lafayette, Indiana; Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, Iowa; Molecular Immunology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, Bethesda, Maryland Gene expression profiles demonstrate that a group of key stress-responsive genes are associated with radiation exposure and may contribute to cellular

20

Quantification of Contralateral Breast Dose and Risk Estimate of Radiation-Induced Contralateral Breast Cancer Among Young Women Using Tangential Fields and Different Modes of Breathing  

SciTech Connect

Purpose: Whole breast irradiation with deep-inspiration breath-hold (DIBH) technique among left-sided breast cancer patients significantly reduces cardiac irradiation; however, a potential disadvantage is increased incidental irradiation of the contralateral breast. Methods and Materials: Contralateral breast dose (CBD) was calculated by comparing 400 treatment plans of 200 left-sided breast cancer patients whose tangential fields had been planned on gated and nongated CT data sets. Various anatomic and field parameters were analyzed for their impact on CBD. For a subgroup of patients (aged {<=}45 years) second cancer risk in the contralateral breast (CB) was modeled by applying the linear quadratic model, compound models, and compound models considering dose-volume information (DVH). Results: The mean CBD was significantly higher in DIBH with 0.69 Gy compared with 0.65 Gy in normal breathing (P=.01). The greatest impact on CBD was due to a shift of the inner field margin toward the CB in DIBH (mean 0.4 cm; range, 0-2), followed by field size in magnitude. Calculation with different risk models for CBC revealed values of excess relative risk/Gy ranging from 0.48-0.65 vs 0.46-0.61 for DIBH vs normal breathing, respectively. Conclusion: Contralateral breast dose, although within a low dose range, was mildly but significantly increased in 200 treatment plans generated under gated conditions, predominately due to a shift in the medial field margin. Risk modeling for CBC among women aged {<=}45 years also pointed to a higher risk when comparing DIBH with normal breathing. This risk, however, was substantially lower in the model considering DVH information. We think that clinical decisions should not be affected by this small increase in CBD with DIBH because DIBH is effective in reducing the dose to the heart in all patients.

Zurl, Brigitte, E-mail: brigitte.zurl@klinikum-graz.at [Department of Therapeutic Radiology and Oncology, Medical University of Graz (Austria)] [Department of Therapeutic Radiology and Oncology, Medical University of Graz (Austria); Stranzl, Heidi; Winkler, Peter; Kapp, Karin Sigrid [Department of Therapeutic Radiology and Oncology, Medical University of Graz (Austria)] [Department of Therapeutic Radiology and Oncology, Medical University of Graz (Austria)

2013-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Low Dose Radiation Research Program: Regulation of NF-kB and MnSOD in Low  

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

NF-kB and MnSOD in Low Dose Radiation-Induced Adaptive NF-kB and MnSOD in Low Dose Radiation-Induced Adaptive Responses in Mouse and Human Skin Cells Jian Jian Li School of Health Sciences, Purdue University West Lafayette, Indiana Why this Project? To determine if low dose ionizing radiation-induced adaptive responses in skin cells are mediated by activation of signaling networks. Project Goals To evaluate the signaling networks involving transcription factor NF-kB and the mitochondrial antioxidant protein MnSOD. To determine if NF-kB is activated by low dose radiation in vivo. To determine if NF-kB activation is critical in the pathways that produce adaptive responses. Experimental Approach Cells transfected with NF-kB luciferase responder genes will be used to define a dose-response relationship for activation of the NF-kB gene. NF-kB

22

Low Dose Responses in Human Cells and Molecular Mechanisms of Adaptation  

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Responses in Human Cells and Molecular Mechanisms of Adaptation Responses in Human Cells and Molecular Mechanisms of Adaptation Joe Gray Priscilla Cooper Lawrence Berkeley National Laboratory Abstract The radiation Adaptive Response (adaptation, or AR) is a well documented, although evidently highly variable, protective phenomenon in which exposures to low-dose or low-dose-rate ionizing radiation result in reduced deleterious effects of subsequent higher exposures. Protection has been reported against a variety of biologically important endpoints, but its variability as a function of cell and tissue type and its genetic control are not well understood. The adaptive response is predicted to result in a non-linear dose response for cancer risk in the low dose range. However, the molecular mechanism(s) remain unknown, and such information is

23

Genetic, cell-type, and tissue variation in low-dose and adaptive...  

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goals are to understand the low-dose and adaptive response mechanisms of the mammary gland in order to build a mechanistic model for predicting an individuals risk for...

24

Genetic, cell-type, and tissue variation in low-dose and adaptive...  

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goals are to understand the low-dose and adaptive response mechanisms of the mammary gland in order to build a mechanistic model for predicting an individual's risk for breast...

25

Adaptive Responses to Low Dose/Low Dose-Rate γ-Rays in Normal Human Fibroblasts:  

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Responses to Low Dose/Low Dose-Rate γ-Rays in Normal Human Fibroblasts: Responses to Low Dose/Low Dose-Rate γ-Rays in Normal Human Fibroblasts: The Role of Oxidative Metabolism Edouard I. Azzam 1 , Sonia M. de Toledo 1 , Badri N. Pandey 1 , Perumal Venkatachalam 1 , Manuela Buoannano 1 , Zhi Yang 1 , Ling Li 3 , Donna M. Gordon 2 , Roger W. Howell 1 , Debkumar Pain 2 and Douglas R. Spitz 3 1 Department of Radiology, 2 Department of Pharmacology and Physiology, UMDNJ-New Jersey Medical School, Newark, NJ 3 Free Radical and Radiation Biology Program, University of Iowa, Iowa City, IA To investigate low dose/low dose-rate effects of low linear energy transfer ionizing radiation, we used γ-irradiated cells adapted to grow in three-dimensional architecture that mimics cell growth in vivo. We determined cellular, molecular and biochemical changes in these

26

Measurements of prompt radiation induced conductivity of Kapton.  

SciTech Connect

We performed measurements of the prompt radiation induced conductivity in thin samples of Kapton (polyimide) at the Little Mountain Medusa LINAC facility in Ogden, UT. Three mil samples were irradiated with a 0.5 {mu}s pulse of 20 MeV electrons, yielding dose rates of 1E9 to 1E10 rad/s. We applied variable potentials up to 2 kV across the samples and measured the prompt conduction current. Analysis rendered prompt conductivity coefficients between 6E-17 and 2E-16 mhos/m per rad/s, depending on the dose rate and the pulse width.

Preston, Eric F. (ITT Corporation, Colorado Springs, CO); Zarick, Thomas Andrew; Sheridan, Timothy J.; Hartman, E. Frederick; Stringer, Thomas Arthur (ITT Corporation, Colorado Springs, CO)

2010-10-01T23:59:59.000Z

27

Low Dose Radiation Research Program: Genetic Control of Repair and Adaptive  

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Repair and Adaptive Responses to Low-level DNA Damage Repair and Adaptive Responses to Low-level DNA Damage James E. Haber Brandeis University Why This Project In order to fully understand mechanisms resulting in effects of low dose, whole system rather than cells must be examined. Although not identical to mammalian systems, simple systems usually have many similarities and give direction for further study of more complex systems. We use the budding yeast, Saccharomyces cerevisiae, as a model system because it is easy to manipulate and its genome is simple and well characterized. Project Goals Examine mechanisms and effects of low dose radiation response for: Genetic recombination mechanisms that lead to genomic instability Genetic factors that affect individual susceptibility to low-dose radiation The adaptive response

28

Delayed Radiation-Induced Vasculitic Leukoencephalopathy  

SciTech Connect

Purpose: Recently, single-fraction, high-dosed focused radiation therapy such as that administered by Gamma Knife radiosurgery has been used increasingly for the treatment of metastatic brain cancer. Radiation therapy to the brain can cause delayed leukoencephalopathy, which carries its own significant morbidity and mortality. While radiosurgery-induced leukoencephalopathy is known to be clinically different from that following fractionated radiation, pathological differences are not well characterized. In this study, we aimed to integrate novel radiographic and histopathologic observations to gain a conceptual understanding of radiosurgery-induced leukoencephalopathy. Methods and Materials: We examined resected tissues of 10 patients treated at Yale New Haven Hospital between January 1, 2009, and June 30, 2010, for brain metastases that had been previously treated with Gamma Knife radiosurgery, who subsequently required surgical management of a symptomatic regrowing lesion. None of the patients showed pathological evidence of tumor recurrence. Clinical and magnetic resonance imaging data for each of the 10 patients were then studied retrospectively. Results: We provide evidence to show that radiosurgery-induced leukoencephalopathy may present as an advancing process that extends beyond the original high-dose radiation field. Neuropathologic examination of the resected tissue revealed traditionally known leukoencephalopathic changes including demyelination, coagulation necrosis, and vascular sclerosis. Unexpectedly, small and medium-sized vessels revealed transmural T-cell infiltration indicative of active vasculitis. Conclusions: We propose that the presence of a vasculitic component in association with radiation-induced leukoencephalopathy may facilitate the progressive nature of the condition. It may also explain the resemblance of delayed leukoencephalopathy with recurring tumor on virtually all imaging modalities used for posttreatment follow-up.

Rauch, Philipp J. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Faculty of Medicine, University of Heidelberg, Heidelberg (Germany); Park, Henry S. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Knisely, Jonathan P.S. [Department of Radiation Medicine, North Shore University Hospital, Manhasset, New York (United States); Chiang, Veronica L. [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States); Vortmeyer, Alexander O., E-mail: alexander.vortmeyer@yale.edu [Departments of Pathology and Neurosurgery, Yale University School of Medicine, New Haven, Connecticut (United States)

2012-05-01T23:59:59.000Z

29

Measurements of prompt radiation induced conductivity in Teflon (PTFE).  

SciTech Connect

We performed measurements of the prompt radiation induced conductivity (RIC) in thin samples of Teflon (PTFE) at the Little Mountain Medusa LINAC facility in Ogden, UT. Three mil (76.2 microns) samples were irradiated with a 0.5 %CE%BCs pulse of 20 MeV electrons, yielding dose rates of 1E9 to 1E11 rad/s. We applied variable potentials up to 2 kV across the samples and measured the prompt conduction current. Details of the experimental apparatus and analysis are reported in this report on prompt RIC in Teflon.

Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.; Preston, E. [ITT Exelis Mission Systems, Colorado Springs, CO

2013-05-01T23:59:59.000Z

30

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-

31

Low-Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer  

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Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Bobby R. Scott, Ph.D. and Jennifer D. Di Palma Lovelace Respiratory Research Institute, 2425 Ridgecrest Drive SE Albuquerque, NM 87108 USA Life on earth evolved in a low-level ionizing radiation environment comprised of terrestrial radiation and cosmic rays. Today we all reside in an ionizing radiation environment comprised of both natural background radiation and radiation from human activities (e.g., Chernobyl accident). An evolutionary benefit of the interaction of low-level, low linear-energy-transfer (LET) ionizing radiation with mammalian life forms on earth is adapted protection. Adapted protection involves low-dose/dose-rate, low-LET radiation induced high-fidelity DNA repair in cooperation with normal apoptosis (presumed p53

32

A Prospective Cohort Study on Radiation-induced Hypothyroidism: Development of an NTCP Model  

Science Conference Proceedings (OSTI)

Purpose: To establish a multivariate normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism. Methods and Materials: The thyroid-stimulating hormone (TSH) level of 105 patients treated with (chemo-) radiation therapy for head-and-neck cancer was prospectively measured during a median follow-up of 2.5 years. Hypothyroidism was defined as elevated serum TSH with decreased or normal free thyroxin (T4). A multivariate logistic regression model with bootstrapping was used to determine the most important prognostic variables for radiation-induced hypothyroidism. Results: Thirty-five patients (33%) developed primary hypothyroidism within 2 years after radiation therapy. An NTCP model based on 2 variables, including the mean thyroid gland dose and the thyroid gland volume, was most predictive for radiation-induced hypothyroidism. NTCP values increased with higher mean thyroid gland dose (odds ratio [OR]: 1.064/Gy) and decreased with higher thyroid gland volume (OR: 0.826/cm{sup 3}). Model performance was good with an area under the curve (AUC) of 0.85. Conclusions: This is the first prospective study resulting in an NTCP model for radiation-induced hypothyroidism. The probability of hypothyroidism rises with increasing dose to the thyroid gland, whereas it reduces with increasing thyroid gland volume.

Boomsma, Marjolein J.; Bijl, Hendrik P.; Christianen, Miranda E.M.C.; Beetz, Ivo; Chouvalova, Olga; Steenbakkers, Roel J.H.M. [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Laan, Bernard F.A.M. van der [Department of Otorhinolaryngology/Head and Neck Surgery, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Wolffenbuttel, Bruce H.R. [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Endocrinology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Oosting, Sjoukje F. [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Medical Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Schilstra, Cornelis [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)] [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A., E-mail: j.a.langendijk@umcg.nl [Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen (Netherlands)

2012-11-01T23:59:59.000Z

33

Organ sample generator for expected treatment dose construction and adaptive inverse planning optimization  

Science Conference Proceedings (OSTI)

Purpose: To create an organ sample generator (OSG) for expected treatment dose construction and adaptive inverse planning optimization. The OSG generates random samples of organs of interest from a distribution obeying the patient specific organ variation probability density function (PDF) during the course of adaptive radiotherapy. Methods: Principle component analysis (PCA) and a time-varying least-squares regression (LSR) method were used on patient specific geometric variations of organs of interest manifested on multiple daily volumetric images obtained during the treatment course. The construction of the OSG includes the determination of eigenvectors of the organ variation using PCA, and the determination of the corresponding coefficients using time-varying LSR. The coefficients can be either random variables or random functions of the elapsed treatment days depending on the characteristics of organ variation as a stationary or a nonstationary random process. The LSR method with time-varying weighting parameters was applied to the precollected daily volumetric images to determine the function form of the coefficients. Eleven h and n cancer patients with 30 daily cone beam CT images each were included in the evaluation of the OSG. The evaluation was performed using a total of 18 organs of interest, including 15 organs at risk and 3 targets. Results: Geometric variations of organs of interest during h and n cancer radiotherapy can be represented using the first 3 {approx} 4 eigenvectors. These eigenvectors were variable during treatment, and need to be updated using new daily images obtained during the treatment course. The OSG generates random samples of organs of interest from the estimated organ variation PDF of the individual. The accuracy of the estimated PDF can be improved recursively using extra daily image feedback during the treatment course. The average deviations in the estimation of the mean and standard deviation of the organ variation PDF for h and n cancer radiotherapy were less than 2 and 1 mm, respectively, for most organs after the second week of treatment. After the first three weeks of treatment, the mean discrepancy of the dose estimation accuracy was within 1% for most of organs, the corresponding standard deviation was within 2.5% for parotids, the brain stem and the cochleae, and within 1% for other organs. Conclusions: A patient specific OSG is feasible and can be used to generate random samples of organs of interest for the expected treatment dose construction and adaptive inverse planning. The accuracy of the OSG can be improved continuously and recursively during the adaptive treatment course using daily volumetric image feedback.

Nie Xiaobo; Liang Jian; Yan Di [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan 48073 (United States)

2012-12-15T23:59:59.000Z

34

Radiation induced strand breakage analyzed by tunel technique  

E-Print Network (OSTI)

The objective of this research is to fully characterize the effectiveness and limits of using the terminal deoxynucleotidyl transferase mediated biotin-dUTP nick end labeling (TUNEL) technique for analysis of radiation induced strand breakage. If the TUNEL technique is found valuable, it could be applied to develop a biodosimetry protocol, primarily useful for individuals exposed in radiological accidents. Several techniques currently in use include fluorescent in-situ hybridization, the comet assay and the dicentric assay, yet each has drawbacks such as limited sensitivity or considerable preparation time. Recently, the TUNEL assay has been used in studies by Harvey and Ford (1997) to investigate chromatid breaks due to restriction enzymes. This research uses similar protocols to examine breaks due to radiation. Chinese hamster ovary (CHO) cells were cultured and exposed to X rays, receiving a dose ranging from 0 to 2 Gy. Slides were created using a standard metaphase chromosome preparation technique, followed by the TUNEL reaction to highlight chromosome breaks. The results were used to build a dose response curve. Although the expected increase in TUNEL positives per metaphase cell with increased x-ray dose was seen, large errors were associated with the results rendering TUNEL assay less than ideal for biodosimetry purposes. Additionally, TUNEL is not very effective at high doses because each TUNEL positive becomes indistinguishable from neighboring positives due to the high number of positives on each chromosome.

Reynolds, Marissa Dawn

2003-01-01T23:59:59.000Z

35

Characterization of adaptive statistical iterative reconstruction algorithm for dose reduction in CT: A pediatric oncology perspective  

Science Conference Proceedings (OSTI)

Purpose: This study demonstrates a means of implementing an adaptive statistical iterative reconstruction (ASiR Trade-Mark-Sign ) technique for dose reduction in computed tomography (CT) while maintaining similar noise levels in the reconstructed image. The effects of image quality and noise texture were assessed at all implementation levels of ASiR Trade-Mark-Sign . Empirically derived dose reduction limits were established for ASiR Trade-Mark-Sign for imaging of the trunk for a pediatric oncology population ranging from 1 yr old through adolescence/adulthood. Methods: Image quality was assessed using metrics established by the American College of Radiology (ACR) CT accreditation program. Each image quality metric was tested using the ACR CT phantom with 0%-100% ASiR Trade-Mark-Sign blended with filtered back projection (FBP) reconstructed images. Additionally, the noise power spectrum (NPS) was calculated for three common reconstruction filters of the trunk. The empirically derived limitations on ASiR Trade-Mark-Sign implementation for dose reduction were assessed using (1, 5, 10) yr old and adolescent/adult anthropomorphic phantoms. To assess dose reduction limits, the phantoms were scanned in increments of increased noise index (decrementing mA using automatic tube current modulation) balanced with ASiR Trade-Mark-Sign reconstruction to maintain noise equivalence of the 0% ASiR Trade-Mark-Sign image. Results: The ASiR Trade-Mark-Sign algorithm did not produce any unfavorable effects on image quality as assessed by ACR criteria. Conversely, low-contrast resolution was found to improve due to the reduction of noise in the reconstructed images. NPS calculations demonstrated that images with lower frequency noise had lower noise variance and coarser graininess at progressively higher percentages of ASiR Trade-Mark-Sign reconstruction; and in spite of the similar magnitudes of noise, the image reconstructed with 50% or more ASiR Trade-Mark-Sign presented a more smoothed appearance than the pre-ASiR Trade-Mark-Sign 100% FBP image. Finally, relative to non-ASiR Trade-Mark-Sign images with 100% of standard dose across the pediatric phantom age spectrum, similar noise levels were obtained in the images at a dose reduction of 48% with 40% ASIR Trade-Mark-Sign and a dose reduction of 82% with 100% ASIR Trade-Mark-Sign . Conclusions: The authors' work was conducted to identify the dose reduction limits of ASiR Trade-Mark-Sign for a pediatric oncology population using automatic tube current modulation. Improvements in noise levels from ASiR Trade-Mark-Sign reconstruction were adapted to provide lower radiation exposure (i.e., lower mA) instead of improved image quality. We have demonstrated for the image quality standards required at our institution, a maximum dose reduction of 82% can be achieved using 100% ASiR Trade-Mark-Sign ; however, to negate changes in the appearance of reconstructed images using ASiR Trade-Mark-Sign with a medium to low frequency noise preserving reconstruction filter (i.e., standard), 40% ASiR Trade-Mark-Sign was implemented in our clinic for 42%-48% dose reduction at all pediatric ages without a visually perceptible change in image quality or image noise.

Brady, S. L.; Yee, B. S.; Kaufman, R. A. [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, Tennessee 38105 (United States)

2012-09-15T23:59:59.000Z

36

'Slow-Blooming Phases' in High Dose  

Science Conference Proceedings (OSTI)

Ab Initio Study of Radiation-Induced Amorphization Mechanisms in SiC and ZrC ... and Irradiation Hardening of Zircaloy during Low Dose Neutron Irradiation at...

37

Radiation-Induced Effects on Microstructure  

Science Conference Proceedings (OSTI)

Irradiation of materials with particles that are sufficiently energetic to create atomic displacements can induce significant microstructural alteration, ranging from crystalline-to-amorphous phase transitions to the generation of large concentrations of point defect or solute aggregates in crystalline lattices. These microstructural changes typically cause significant changes in the physical and mechanical properties of the irradiated material. A variety of advanced microstructural characterization tools are available to examine the microstructural changes induced by particle irradiation, including electron microscopy, atom probe field ion microscopy, X-ray scattering and spectrometry, Rutherford backscattering spectrometry, nuclear reaction analysis, and neutron scattering and spectrometry. Numerous reviews, which summarize the microstructural changes in materials associated with electron and heavy ion or neutron irradiation, have been published. These reviews have focused on pure metals as well as model alloys, steels, and ceramic materials. In this chapter, the commonly observed defect cluster morphologies produced by particle irradiation are summarized and an overview is presented on some of the key physical parameters that have a major influence on microstructural evolution of irradiated materials. The relationship between microstructural changes and evolution of physical and mechanical properties is then summarized, with particular emphasis on eight key radiation-induced property degradation phenomena. Typical examples of irradiated microstructures of metals and ceramic materials are presented. Radiation-induced changes in the microstructure of organic materials such as polymers are not discussed in this overview.

Zinkle, Steven J [ORNL

2012-01-01T23:59:59.000Z

38

MECHANISTIC STUDY OF LOW DOSE RADIATION INDUCED PROTEOLYTIC CASCADES  

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

Cells organize into tissue-like structures which recapitulate the intact human mammary gland morphology (Figure 1) enabling molecular level study of how normal tissues respond...

39

Low Dose Radiation Research Program: Ionizing Radiation-induced...  

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

p53-directed, DNA damage response pathway. The p53 protein, activated indirectly by the ATM protein kinase, transactivates target genes and thus induces cell cycle progression...

40

Radiation induced corrosion of steel; Strlningsinducerad korrosion av stl.  

E-Print Network (OSTI)

??The aim of this thesis was to investigate the influence of aqueous radiation induced oxidants on stainless steel. This was done by exposing the steel (more)

Nilsson, Oskar

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" from the National Library of EnergyBeta (NLEBeta).
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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

Modulating radiation induced TGFβ and ATM signaling in the DNA damage  

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Modulating radiation induced TGFβ and ATM signaling in the DNA damage Modulating radiation induced TGFβ and ATM signaling in the DNA damage response Jennifer A. Anderson Gray Institute for Radiation Oncology and Biology Abstract Both the ATM and TGFβ signal transduction pathways are essential for cellular and tissue control responses to ionizing radiation and aberrant modifications to these pathways are extensive in cancer. We hypothesize that the ATM and TGFβ signaling pathways are fully induced at high doses of acute low-LET radiation, whereas only partially induced at low doses. Numerous studies have linked the p38 MAPK signaling pathway with the ATM DNA damage response, and others have shown that TGFβ stimulation results in the phosphorylation of p38 MAPK. Our aim is to perturb potential crosstalk between ATM, TGFβ and p38 MAPK at the DNA damage level and

42

Low Dose Radiation Program: Workshop VI Abstracts  

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Workshop VI Principal Investigator and Abstracts Workshop VI Principal Investigator and Abstracts Anderson, Carl Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Averbeck, Dietrich Cellular Responses at Low Doses of Ionizing Radiation. Azzam, Edouard Adaptive Responses to Low Dose/Low Dose-Rate ?-Rays in Normal Human Fibroblasts: The Role of Oxidative Metabolism. Bailey, Susan The Role of Telomere Dysfunction in Driving Genomic Instability. Balajee, Adayabalam Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System. Barcellos-Hoff, Mary Helen Imaging Bioinformatics for Mapping Multidimensional Responses. Barcellos-Hoff, Mary Helen Biological Response to Radiation Mediated through the Microenvironment and

43

Low Dose Radiation Research Program: Universities  

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Universities Universities | Duke University | Loma Linda University | Northwestern University | University of Chicago | University of California Davis | Northwestern University University of Chicago University of California Davis Effects of Low Dose Irradiation on NF-κB Signaling Networks and Mitochondria Principal Investigator: Dr. Gayle Woloschak DOE Low Dose Research Program Projects Low dose-low dose rate irradiation leads to long term changes in numbers of mitochondria and mitochondrial genomes - Principal Investigator: Gayle Woloschak, Professor, Department of Radiation Oncology, Northwestern University, Chicago, IL, USA NF-κB-mediated pro-survival network in low dose radiation-induced adaptive protection - Principal Investigator: Jian Jian Li, Professor, Department of Radiation Oncology, University of California Davis, Davis,

44

Radiation-Induced Bystander Effects and Relevance to Human Radiation  

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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

45

Low Dose Radiation Research Program: Radiation Response in Normal...  

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

genes. Using rigorous computational methods, we characterized the dose-dependent, radiation-induced gene expression of HSF-42, a primary cell culture. Our preliminary results...

46

Role of the area postrema in radiation-induced taste aversion learning and emesis in cats  

SciTech Connect

The role of the area postrema in radiation-induced emesis and taste aversion learning and the relationship between these behaviors were studied in cats. The potential involvement of neural factors which might be independent of the area postrema was minimized by using low levels of ionizing radiation (100 rads at a dose rate of 40 rads/min) to elicit a taste aversion, and by using body-only exposures (4500 and 6000 rads at 450 rads/min) to produce emesis. Lesions of the area postrema disrupted both taste aversion learning and emesis following irradiation. These results, which indicate that the area postrema is involved in the mediation of both radiation-induced emesis and taste aversion learning in cats under these experimental conditions, are interpreted as being consistent with the hypotheses that similar mechanisms mediate both responses to exposure to ionizing radiation, and that the taste aversion learning paradigm can therefore serve as a model system for studying radiation-induced emesis.

Rabin, B.M.; Hunt, W.A.; Chedester, A.L.; Lee, J.

1986-01-01T23:59:59.000Z

47

Gamma knife radiosurgery of radiation-induced intracranial tumors: Local control, outcomes, and complications  

Science Conference Proceedings (OSTI)

Purpose: To determine local control (LC) and complication rates for patients who underwent radiosurgery for radiation-induced intracranial tumors. Methods and Materials: Review of a prospectively maintained database (2,714 patients) identified 16 patients (20 tumors) with radiation-induced tumors treated with radiosurgery between 1990 and 2004. Tumor types included typical meningioma (n = 17), atypical meningioma (n = 2), and schwannoma (n 1). Median patient age at radiosurgery was 47.5 years (range, 27-70 years). The median tumor margin dose was 16 Gy (range, 12-20 Gy). Median follow-up was 40.2 months (range, 10.8-146.2 months). Time-to-event outcomes were calculated with Kaplan-Meier estimates. Results: Three-year and 5-year LC rates were 100%. Three-year and 5-year overall survival rates were 92% and 80%, respectively. Cause-specific survival rates at 3 and 5 years were 100%. Three patients died: 1 had in-field progression 65.1 months after radiosurgery and later died of the tumor, 1 died of progression of a preexisting brain malignancy, and 1 died of an unrelated cause. One patient had increased seizure activity that correlated with development of edema seen on neuroimaging. Conclusions: LC, survival, and complication rates in our series are comparable to those in previous reports of radiosurgery for intracranial meningiomas. Also, LC rates with radiosurgery are at least comparable to those of surgical series for radiation-induced meningiomas. Radiosurgery is a safe and effective treatment option for radiation-induced intracranial tumors, most of which are typical meningiomas.

Jensen, Ashley W. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Pollock, Bruce E. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Department of Neurologic Surgery, Mayo Clinic, Rochester, MN (United States); Stafford, Scott L. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Link, Michael J. [Department of Neurologic Surgery, Mayo Clinic, Rochester, MN (United States); Garces, Yolanda I. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Foote, Robert L. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Gorman, Deborah A. [Department of Neurologic Surgery, Mayo Clinic, Rochester, MN (United States); Schomberg, Paula J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

2005-05-01T23:59:59.000Z

48

A Critical Examination of the Adaptive Response for Cytogenetic Damagein Human Cells, and Insights into the Adaptive Response Mechanism  

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

Critical Examination of the Adaptive Response for Cytogenetic Damage Critical Examination of the Adaptive Response for Cytogenetic Damage in Human Cells, and Insights into the Adaptive Response Mechanism Björn E. Rydberg, Torsten Groesser, Antoine Snijders, Kelly Trego, Ju Han, Do Yup Lee, Bahram Parvin, Trent Northen, Andrew J. Wyrobek, and Priscilla K. Cooper Berkeley Lab SFA P.I.: Gary Karpen Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 Goal: Task 1 of the Berkeley Lab SFA is designed to identify adaptive response (AR) mechanisms that may affect risk of developing radiation-induced cancer and to assess the linearity with dose of processes that influence mammary gland carcinogenesis. We use both in vitro and in vivo experimental systems in a parallelogram strategy. Our human cell culture

49

Low Dose Radiation Research Program: Chaun-Yuan Li  

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Chaun-Yuan Li Chaun-Yuan Li Radiation Biology Research, Duke University Medical Center Funded Projects Molecular Characterization of the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing, abstract, description. Technical Abstracts 2006 Workshop: The Roles of Superoxide Dismutage (SOD) in Low Dose Radiation Induced Adaptive Response Yang, Z., Chuang, E., Batinic-Haberle, I., and Li, C.-Y. 2005 Workshop: Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Li, C.-Y., Guo, Z., Yang, Z., and Chuang, E. 2003 Workshop: Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Li, C.-Y. and Chuang, E. Publications Li, F., Sonveaux, P., Rabbani, Z.N., Liu, S., Yan, B., Huang, Q.,

50

A Critical Examination of the Adaptive Response for Cytogenetic Damage in  

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

Critical Examination of the Adaptive Response for Cytogenetic Damage in Critical Examination of the Adaptive Response for Cytogenetic Damage in Human Cells, and Insights into the Adaptive Response Mechanism Björn E. Rydberg Lawrence Berkeley National Laboratory Abstract Goal: Task 1 of the Berkeley Lab SFA is designed to identify adaptive response (AR) mechanisms that may affect risk of developing radiation-induced cancer and to assess the linearity with dose of processes that influence mammary gland carcinogenesis. We use both in vitro and in vivo experimental systems in a parallelogram strategy. Our human cell culture model will elucidate the molecular mechanisms of the AR and investigate the relationships in target vs. non-target cells between a range of cancer-relevant endpoints potentially affected by adaptation such

51

Low Dose Radiation Research Program: Cytogenetic tests of Radiobiologi...  

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relevant low-dose range (less than 0.1 Gy). Relate chromosome damage to radiation-induced cancer. Research Approach By studying molecular mechanisms relevant to low doses and low...

52

Analysis of time-dependent radiation-induced conductivity in dielectrics and effect on cable SGEMP  

SciTech Connect

Analytic and numerical solutions are presented for a simple time-dependent solid-state band model of radiation-induced conductivity in polyethelene and Teflon. The analytic solution is found to provide insight to physical processes dominant in various intervals of time throughout the radiation pulse. The numerical solution provides a representation for the dose-dependent proportionality factor F(..gamma..), proposed by van Lint et al, used to calculate prompt conductivity from sigma/rho/ = F(..gamma..)..gamma... At high doses, F(..gamma..) is an order of magnitude smaller than at low doses. This decrease of F(..gamma..) is due to bimolecular recombination, an effect apparently not previously reported experimentally. The reduction in F(..gamma..) at high doses is shown to enhance the short circuit current for a cable SGEMP model of residual gaps by a factor of three. In addition, the dose-dependent behavior of F(..gamma..) can significantly alter the shape and time of occurrence of the peak of the waveform of this short circuit current compared to corresponding results for a dose-independent factor.

Shaeffer, D.L.; Siegel, J.M.

1982-12-01T23:59:59.000Z

53

Radiation-induced surface degradation of GaAs and high electron mobility transistor structures  

Science Conference Proceedings (OSTI)

Transistor heterostructures with high-carrier-mobility have been studied. It is shown that, as the {gamma}-irradiation dose {Phi} increases, their degradation occurs in the following sequence. (i) At {Phi} 0.2-eV decrease in the diffusion energy of intrinsic defects and, probably, atmospheric oxygen. (ii) At {Phi} > 10{sup 7} rad, highly structurally disordered regions larger than 1 {mu}m are formed near microscopic defects or dislocations. (iii) At {Phi} > 10{sup 8} rad, there occurs degradation of the internal AlGaAs/InGaAs/GaAs interfaces and the working channel. An effective method for studying the degradation processes in heterostructures is to employ a set of structural diagnostic methods to analyze processes of radiation-induced and aging degradation, in combination with theoretical simulation of the occurring processes.

Bobyl, A. V.; Konnikov, S. G.; Ustinov, V. M.; Baidakova, M. V.; Maleev, N. A.; Sakseev, D. A. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation); Konakova, R. V., E-mail: konakova@isp.kiev.ua; Milenin, V. V.; Prokopenko, I. V. [National Academy of Sciences of Ukraine, Lashkaryov Institute of Semiconductor Physics (Ukraine)

2012-06-15T23:59:59.000Z

54

Radiation-Induced Cancers From Modern Radiotherapy Techniques: Intensity-Modulated Radiotherapy Versus Proton Therapy  

Science Conference Proceedings (OSTI)

Purpose: To assess and compare secondary cancer risk resulting from intensity-modulated radiotherapy (IMRT) and proton therapy in patients with prostate and head-and-neck cancer. Methods and Materials: Intensity-modulated radiotherapy and proton therapy in the scattering mode were planned for 5 prostate caner patients and 5 head-and-neck cancer patients. The secondary doses during irradiation were measured using ion chamber and CR-39 detectors for IMRT and proton therapy, respectively. Organ-specific radiation-induced cancer risk was estimated by applying organ equivalent dose to dose distributions. Results: The average secondary doses of proton therapy for prostate cancer patients, measured 20-60cm from the isocenter, ranged from 0.4 mSv/Gy to 0.1 mSv/Gy. The average secondary doses of IMRT for prostate patients, however, ranged between 3 mSv/Gy and 1 mSv/Gy, approximately one order of magnitude higher than for proton therapy. Although the average secondary doses of IMRT were higher than those of proton therapy for head-and-neck cancers, these differences were not significant. Organ equivalent dose calculations showed that, for prostate cancer patients, the risk of secondary cancers in out-of-field organs, such as the stomach, lungs, and thyroid, was at least 5 times higher for IMRT than for proton therapy, whereas the difference was lower for head-and-neck cancer patients. Conclusions: Comparisons of organ-specific organ equivalent dose showed that the estimated secondary cancer risk using scattering mode in proton therapy is either significantly lower than the cases in IMRT treatment or, at least, does not exceed the risk induced by conventional IMRT treatment.

Yoon, Myonggeun, E-mail: mxy131@ncc.re.k [Proton Therapy Center, National Cancer Center, Goyang (Korea, Republic of); Ahn, Sung Hwan; Kim, Jinsung; Shin, Dong Ho; Park, Sung Yong; Lee, Se Byeong; Shin, Kyung Hwan; Cho, Kwan Ho [Proton Therapy Center, National Cancer Center, Goyang (Korea, Republic of)

2010-08-01T23:59:59.000Z

55

Radiation-induced solitary waves in hot plasmas of accretion disks  

E-Print Network (OSTI)

It is shown that the existence of radiation-induced solitary waves in hot plasmas of accretion disks depends on the radial temperature profile.

Fedor V. Prigara

2005-07-08T23:59:59.000Z

56

Role of ATM kinase in ionizing radiation induced DNA damage response...  

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

ATM kinase in ionizing radiation induced DNA damage response in human neural stemprogenitor cells and differentiated cell types Adayabalam Balajee Columbia University Medical...

57

Quantitative Ultrasonic Evaluation of Radiation-Induced Late Tissue Toxicity: Pilot Study of Breast Cancer Radiotherapy  

Science Conference Proceedings (OSTI)

Purpose: To investigate the use of advanced ultrasonic imaging to quantitatively evaluate normal-tissue toxicity in breast-cancer radiation treatment. Methods and Materials: Eighteen breast cancer patients who received radiation treatment were enrolled in an institutional review board-approved clinical study. Radiotherapy involved a radiation dose of 50.0 to 50.4 Gy delivered to the entire breast, followed by an electron boost of 10.0 to 16.0 Gy delivered to the tumor bed. Patients underwent scanning with ultrasound during follow-up, which ranged from 6 to 94 months (median, 22 months) postradiotherapy. Conventional ultrasound images and radio-frequency (RF) echo signals were acquired from treated and untreated breasts. Three ultrasound parameters, namely, skin thickness, Pearson coefficient, and spectral midband fit, were computed from RF signals to measure radiation-induced changes in dermis, hypodermis, and subcutaneous tissue, respectively. Ultrasound parameter values of the treated breast were compared with those of the untreated breast. Ultrasound findings were compared with clinical assessment using Radiation Therapy Oncology Group (RTOG) late-toxicity scores. Results: Significant changes were observed in ultrasonic parameter values of the treated vs. untreated breasts. Average skin thickness increased by 27.3%, from 2.05 {+-} 0.22mm to 2.61 {+-} 0.52mm; Pearson coefficient decreased by 31.7%, from 0.41 {+-} 0.07 to 0.28 {+-} 0.05; and midband fit increased by 94.6%, from -0.92 {+-} 7.35 dB to 0.87 {+-} 6.70 dB. Ultrasound evaluations were consistent with RTOG scores. Conclusions: Quantitative ultrasound provides a noninvasive, objective means of assessing radiation-induced changes to the skin and subcutaneous tissue. This imaging tool will become increasingly valuable as we continue to improve radiation therapy technique.

Liu Tian, E-mail: tliu34@emory.ed [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Zhou Jun [Department of Radiation Oncology, Columbia University Medical Center, New York, NY (United States); Yoshida, Emi J. [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Woodhouse, Shermian A. [Department of Radiation Oncology, Columbia University Medical Center, New York, NY (United States); Schiff, Peter B. [Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA (United States); Wang, Tony J.C. [Department of Radiation Oncology, Columbia University Medical Center, New York, NY (United States); Lu Zhengfeng; Pile-Spellman, Eliza [Department of Radiology, Columbia University Medical Center, New York, NY (United States); Zhang Pengpeng [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Kutcher, Gerald J. [Department of History, Binghamton University, Binghamton, NY (United States)

2010-11-01T23:59:59.000Z

58

Hydrogen peroxide significantly contributes to radiation-induced genomic instability  

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

peroxide significantly contributes to radiation- peroxide significantly contributes to radiation- induced genomic instability Disha Dayal 1 , Sean M. Martin 1 , Sujatha Venkataraman 1 , Charles L. Limoli 2 , Douglas R Spitz 1 . 1 Free Radical and Radiation Biology Program, The University of Iowa, Iowa City, IA- 52246, 2 Department of Radiation Oncology, The University of California, Irvine, CA-92697 Chronic metabolic oxidative stress is associated with genomic instability following exposure to ionizing radiation (IR). Mitochondria have long been known to be a major source of reactive oxygen species (ROS) capable of causing oxidative stress. We hypothesized that radiation damages mitochondria, leading to oxidative stress and eventually genomic instability. This hypothesis is based on preliminary studies in parental

59

Radiation-induced leukemia: Comparative studies in mouse and man  

SciTech Connect

We now have a clear understanding of the mechanism by which radiation-induced (T-cell) leukemia occurs. In irradiated mice (radiation-induced thymic leukemia) and in man (acute lymphoblastic T-cell leukemia, T-ALL) the mechanism of leukemogenesis is surprisingly similar. Expressed in the most elementary terms, T-cell leukemia occurs when T-cell differentiation is inhibited by a mutation, and pre-T cells attempt but fail to differentiate in the thymus. Instead of leaving the thymus for the periphery as functional T-cells they continue to proliferate in the thymus. The proliferating pre- (pro-) T-cells constitute the (early) acute T-cell leukemia (A-TCL). This model for the mechanism of T-cell leukemogenesis accounts for all the properties of both murine and human A-TCL. Important support for the model has recently come from work by Ilan Kirsch and others, who have shown that mutations/deletions in the genes SCL (TAL), SIL, and LCK constitute primary events in the development of T-ALL, by inhibiting differentiation of thymic pre- (pro-) T-cells. This mechanism of T-cell leukemogenesis brings several specific questions into focus: How do early A-TCL cells progress to become potently tumorigenic and poorly treatable Is it feasible to genetically suppress early and/or progressed A-TCL cells What is the mechanism by which the differentiation-inhibited (leukemic) pre-T cells proliferate During the first grant year we have worked on aspects of all three questions.

Haas, M.

1991-01-01T23:59:59.000Z

60

High Dose Heavy Ion Irradiation of Austenitic Stainless Steels ...  

Science Conference Proceedings (OSTI)

Ab Initio Study of Radiation-Induced Amorphization Mechanisms in SiC and ZrC ... of Zircaloy during Low Dose Neutron Irradiation at Nominally 375-440C.

Note: This page contains sample records for the topic "dose radiation-induced adaptive" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


61

Low Dose Radiation Research Program: Are Animals Heterozygous...  

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

lymphocytes from animals of known genotypes. Radiation-induced foci occur in a time and dose dependent manner in the nuclei of normal cells, NBS cells on the other hand, do not...

62

Radiation-Induced Salivary Gland Dysfunction Results From p53-Dependent Apoptosis  

Science Conference Proceedings (OSTI)

Purpose: Radiotherapy for head-and-neck cancer causes adverse secondary side effects in the salivary glands and results in diminished quality of life for the patient. A previous in vivo study in parotid salivary glands demonstrated that targeted head-and-neck irradiation resulted in marked increases in phosphorylated p53 (serine{sup 18}) and apoptosis, which was suppressed in transgenic mice expressing a constitutively active mutant of Akt1 (myr-Akt1). Methods and Materials: Transgenic and knockout mouse models were exposed to irradiation, and p53-mediated transcription, apoptosis, and salivary gland dysfunction were analyzed. Results: The proapoptotic p53 target genes PUMA and Bax were induced in parotid salivary glands of mice at early time points after therapeutic radiation. This dose-dependent induction requires expression of p53 because no radiation-induced expression of PUMA and Bax was observed in p53-/- mice. Radiation also induced apoptosis in the parotid gland in a dose-dependent manner, which was p53 dependent. Furthermore, expression of p53 was required for the acute and chronic loss of salivary function after irradiation. In contrast, apoptosis was not induced in p53-/- mice, and their salivary function was preserved after radiation exposure. Conclusions: Apoptosis in the salivary glands after therapeutic head-and-neck irradiation is mediated by p53 and corresponds to salivary gland dysfunction in vivo.

Avila, Jennifer L. [Department of Physiological Sciences, University of Arizona, Tucson, AZ (United States); Grundmann, Oliver; Burd, Randy [Department of Nutritional Sciences, University of Arizona, Tucson, AZ (United States); Limesand, Kirsten H. [Department of Physiological Sciences, University of Arizona, Tucson, AZ (United States); Department of Nutritional Sciences, University of Arizona, Tucson, AZ (United States)], E-mail: limesank@u.arizona.edu

2009-02-01T23:59:59.000Z

63

Roles of TNFα Signaling and NFκB in Thiol- and Low Dose  

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

Roles of TNFα Signaling and NFκB in Thiol- and Low Dose Radiation-Induced Roles of TNFα Signaling and NFκB in Thiol- and Low Dose Radiation-Induced Adaptive Responses Jeffrey S. Murley The University of Chicago Abstract To better investigate the roles of tumor necrosis factor alpha (TNFα) signaling processes and nuclear transcription factor κB (NFκB) activation on the induction of manganese superoxide dismutase (SOD2) mediated adaptive responses, we employed a two by two experimental matrix that includes the use of both wild type C57BL/6 and C57BL/6 tumor necrosis factor receptor 1 and 2 (TNFR1-R2-) knockout mice, and ras/c-myc transfected wild type and TNFR1-R2- knockout mouse embryo fibroblasts (MEF). MEF were immortalized in order to facilitate their use in our mouse models to test the role of normal or TNFR1-R2- stromal cells and tissues on their responses to thiol

64

Low Dose Radiation Research Program: Jian Jian Li  

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

Jian Jian Li Jian Jian Li School of Health Sciences, Purdue University Newly Funded Projects Regulation of NF-kB and Mn SOD in Low Dose Radiation-Induced Adaptive Responses in Mouse and Human Skin Cells, abstract, description. Technical Abstracts 2006 Workshops: NF-kB Mediated Signaling Network in Low Dose X-Ray Induced Adaptive Protection on Mouse and Human Skin Epithelial Cells Ahmed, K.M., Fan, M., Spitz, and Li, J.J. 2005 Workshops: Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Ionizing Radiation: Induction of NF-κB, MnSOD, 14-3-3ζ and Cyclin B1. Li, J.J., Ahmed, K.M., Fan, M., Dong, S., Spitz, D.R., and Yu, C.-R. 2003 Workshops: Gene Expression Profiles of Human Skin Keratinocytes Exposed to Acute and Chronic Ionizing Radiation Li, J.J., Ozeki, M., Wang, T., Tamae, D., Nelson, D., Wyrobek, A., and

65

Acemannan-containing wound dressing gel reduces radiation-induced skin reactions in C3H mice  

Science Conference Proceedings (OSTI)

To determine (a) whether a wound dressing gel that contains acemannan extracted from aloe leaves affects the severity of radiation-induced acute skin reactions in C3H mice; (b) if so, whether other commercially available gels such as a personal lubricating jelly and a healing ointment have similar effects; and (c) when the wound dressing gel should be applied for maximum effect. Male C3H mice received graded single doses of gamma radiation ranging from 30 to 47.5 Gy to the right leg. In most experiments, the gel was applied daily beginning immediately after irradiation. Dose-response curves were obtained by plotting the percentage of mice that reached or exceeded a given peak skin reaction as a function of dose. Curves were fitted by logit analysis and ED{sub 50} values, and 95% confidence limits were obtained. The average peak skin reactions of the wound dressing gel-treated mice were lower than those of the untreated mice at all radiation doses tested. The ED{sub 50} values for skin reactions of 2.0-2.75 were approximately 7 Gy higher in the wound dressing gel-treated mice. The average peak skin reactions and the ED{sub 50} values for mice treated with personal lubricating jelly or healing ointment were similar to irradiated control values. Reduction in the percentage of mice with skin reactions of 2.5 or more was greatest in the groups that received wound dressing gel for at least 2 weeks beginning immediately after irradiation. There was no effect if gel was applied only before irradiation or beginning 1 week after irradiation. Wound dressing gel, but not personal lubricating jelly or healing ointment, reduces acute radiation-induced skin reactions in C3H mice if applied daily for at least 2 weeks beginning immediately after irradiation. 31 refs., 4 figs., 1 tab.

Roberts, D.B.; Travis, E.L. [Univ. of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

1995-07-15T23:59:59.000Z

66

Transient radiation-induced absorption in the materials for a GSGG laser  

Science Conference Proceedings (OSTI)

Materials used in the optical elements of a 1,061 m GSGG (gadolinium scandium gallium garnet) laser have been tested for transient radiation-induced absorption. The transient radiation-induced absorption in KK1, Schott S7005 and S7010, and M382 glasses have been determined for discrete wavelengths in the range 440--750 nm. Also, the transient radiation-induced absorption in {open_quotes}pure{close_quotes} and MgO doped LiNbO{sub 3} has been measured at 1,061 nm. Mathematical expressions composed of exponentials are fitted to the data.

Brannon, P.J.

1993-11-01T23:59:59.000Z

67

Quantification of radiation induced crosslinking in a commercial, toughened silicone rubber, TR-55, by 1H MQ-NMR  

SciTech Connect

Radiation induced degradation in a commercial, filled silicone composite has been studied by SPME/GC-MS, DMA, DSC, swelling, and Multiple Quantum NMR. Analysis of volatile and semivolatile species indicates degradation via decomposition of the peroxide curing catalyst and radiation induced backbiting reactions. DMA, swelling, and spin-echo NMR analysis indicate a increase in crosslink density of near 100% upon exposure to a cumulative dose of 250 kGray. Analysis of the sol-fraction via Charlseby-Pinner analysis indicates a ratio of chain scission to crosslinking yields of 0.38, consistent with the dominance of the crosslinking observed by DMA, swelling and spin-echo NMR and the chain scissioning reactions observed by MS analysis. Multiple Quantum NMR has revealed a bimodal distribution of residual dipolar couplings near 1 krad/sec and 5 krad/sec in an approximately 90:10 ratio, consistent with bulk network chains and chains associated with the filler surface. Upon exposure to radiation, the mean {Omega}{sub d} for both domains and the width of both domains both increased. The MQ NMR analysis provided increase insight into the effects of ionizing radiation on the network structure of silicone polymers.

Maxwell, R; Chinn, S; Alviso, C; Harvey, C A; Giuliani, J; Wilson, T; Cohenour, R

2008-11-10T23:59:59.000Z

68

Radiation-induced lung injury using a pig model: Evaluation by high-resolution computed tomography  

Science Conference Proceedings (OSTI)

To assess the early phase of radiation-induced lung injury using high-resolution computed tomography (CT) under experimental conditions and to perform precise CT-pathologic correlation. Five Yorkshire pigs received a single dose of 12.5 Gy to the right lower lung. Computed tomographic images were obtained at 2-week intervals. The animals were killed after follow-up periods of 4-16 weeks. The lungs were removed, inflated, fixed, dried, and sliced corresponding to the CT sections. Computed tomography, specimen radiography, and histologic findings were correlated. Various CT findings were observed during the first 16 weeks, including ground-glass opacity, discrete consolidation, patchy consolidation, thickened interlobular septum, and bronchovascular bundle. Ground-glass opacity was associated with thickened alveolar wall and scattered tiny fibrotic foci. Thickened interlobular septum and bronchovascular bundle were the results of fibrosis adjacent to these structures. Discrete consolidation correlated with intraalveolar edema with hemorrhage and infiltration of inflammatory cells. High-resolution CT correlated well with pathology of the lung due to radiation injury as verified by precise radiologic-pathologic correlation. 28 refs., 4 figs., 1 tab.

Takahashi, Masashi; Balazs, G.; Moskowitz, G.W.; Palestro, C.J.; Eacobacci, T.; Khan, A.; Herman, P.G. [Albert Einstein College of Medicine, New Hyde Park, NY (United States)

1995-02-01T23:59:59.000Z

69

Low Dose Radiation Research Program: Bruce E. Lehnert  

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

E. Lehnert E. Lehnert Los Alamos National Laboratory Past Project Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated Cells: Pathways Analysis in Support of Risk Assessment. Technical Abstracts 2002 Workshop: Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Lehnert, B.E., Cary, R., Gadbois, D. and Gupta G. 2001 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. 1999 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. Publications Lehnert, B.E., Radiation bystander effects. U.S.Department of Energy Research News (March 6 issue) Goldberg, Z. and Lehnert, B.E. (2002). Radiation-induced effects in

70

Effect of low-dose, low-LET γ-radiation and BaP injection on pulmonary  

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low-dose, low-LET γ-radiation and BaP injection on pulmonary low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice K. Gott Lovelace Respiratory Research Institute Abstract Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response (Nowosielska et al., 2006), presumably via epigenetic pathways (Scott et al., 2009) and has been implicated as suppressing both alpha-radiation-induced and smoking-related lung cancer (Scott et al. 2009). One of the hypothesized adaptive-response mechanisms by which LDR does so is by activating immune cell function in the lung, which would then increase their anti-cancer surveillance function (Liu, 2007; Bogdandi et al., 2010). One measure of activated immune cell function is their expression of markers on their cell surface that are

71

Low Dose Radiation Research Program: Molecular Mechanisms of  

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Molecular Mechanisms of Radiation-Induced Genomic Instability in Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells. Authors: Howard L. Liber1 and Jeffrey L. Schwartz2. Institutions: 1Colorado State University and 2University of Washington. Knowledge of the signal and target through which radiation induces genomic instability, which we propose to investigate herein, will allow us to model effects at low doses. Such knowledge will aid in understanding variations in the induction of this genomic instability, both among cells and among individuals. This information could also lead to more sensitive measures of instability that could yield accurate measures of instability induction at low doses. We have developed an in-vitro cell model, in which radiation-induced chromosome instability develops in a two-stage process.

72

{sub p}53-Dependent Adaptive Responses in Human Cells Exposed to Space Radiations  

Science Conference Proceedings (OSTI)

Purpose: It has been reported that priming irradiation or conditioning irradiation with a low dose of X-rays in the range of 0.02-0.1 Gy induces a p53-dependent adaptive response in mammalian cells. The aim of the present study was to clarify the effect of space radiations on the adaptive response. Methods and Materials: Two human lymphoblastoid cell lines were used; one cell line bears a wild-type p53 (wtp53) gene, and another cell line bears a mutated p53 (mp53) gene. The cells were frozen during transportation on the space shuttle and while in orbit in the International Space Station freezer for 133 days between November 15, 2008 and March 29, 2009. After the frozen samples were returned to Earth, the cells were cultured for 6 h and then exposed to a challenging X-ray-irradiation (2 Gy). Cellular sensitivity, apoptosis, and chromosome aberrations were scored using dye-exclusion assays, Hoechst33342 staining assays, and chromosomal banding techniques, respectively. Results: In cells exposed to space radiations, adaptive responses such as the induction of radioresistance and the depression of radiation-induced apoptosis and chromosome aberrations were observed in wtp53 cells but not in mp53 cells. Conclusion: These results have confirmed the hypothesis that p53-dependent adaptive responses are apparently induced by space radiations within a specific range of low doses. The cells exhibited this effect owing to space radiations exposure, even though the doses in space were very low.

Takahashi, Akihisa [Department of Biology, School of Medicine, Nara Medical University, Nara (Japan); Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Ibaraki (Japan); Su Xiaoming [Department of Biology, School of Medicine, Nara Medical University, Nara (Japan); Suzuki, Hiromi [Japan Space Forum, Tokyo (Japan); Space Environmental Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Omori, Katsunori [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Ibaraki (Japan); Seki, Masaya; Hashizume, Toko [Space Environmental Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Advanced Engineering Services Company, Limited, Ibaraki (Japan); Shimazu, Toru [Japan Space Forum, Tokyo (Japan); Ishioka, Noriaki [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Ibaraki (Japan); Space Environmental Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima (Japan); Iwasaki, Toshiyasu [Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of the Electric Power Industry of Japan, Tokyo (Japan); Ohnishi, Takeo, E-mail: tohnishi@naramed-u.ac.j [Department of Radiation Oncology, School of Medicine, Nara Medical University, Nara (Japan); Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Ibaraki (Japan)

2010-11-15T23:59:59.000Z

73

Low Dose Radiation Research Program: Wide Expression of LLIR and the  

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

Wide Expression of LLIR and the Biological Consequences Wide Expression of LLIR and the Biological Consequences David J. Chen Lawrence Berkeley National Laboratory Why This Project It is known that changes in gene expression alter biological effects. It is necessary to identify the specific genes that demonstrate altered expression after exposure to low doses of ionizing radiation and to determine pathways involved in DNA damage recognition, signaling, and repair that are associated with radiation-induced adaptive and bystander effects. Project Goals Identification of genes whose transcription is regulated in response to low levels of ionizing radiation Identification of the genes and communication pathways that control these responses to low dose radiation Identification of the cellular and molecular targets that influence

74

Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in  

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Induced DNA Damage Signaling and Repair Responses in Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System Yanrong Su, Jarah Meador and Adayabalam S. Balajee Center for Radiological Research, College of Physicians and Surgeons, Columbia University, 630 West, 168th Street, New York, NY 10032. Exposure to ionizing radiation (IR) inflicts a wide variety of lesions in the genomic DNA. Among them, DNA double strand break (DSB) is considered to be the critical lesion for most of the deleterious radiation effects including carcinogenesis. Much of our knowledge on induction and repair kinetics of DSB has come from studies in two dimensional cell culture systems. However, the damage signaling and repair responses to DSB in tissue microenvironment are largely unknown. Knowledge of tissue responses to

75

NFkB-mediated Prosurvival Network in Low Dose Radiation-induced...  

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

approaches to improve normal tissue protection in caner radiation therapy. We found that ATM, a DNA damage sensor, is induced by LDR and responsible for activation of transcription...

76

Acute Radiation-Induced Nocturia in Prostate Cancer Patients Is Associated With Pretreatment Symptoms, Radical Prostatectomy, and Genetic Markers in the TGF{beta}1 Gene  

Science Conference Proceedings (OSTI)

Purpose: After radiation therapy for prostate cancer, approximately 50% of the patients experience acute genitourinary symptoms, mostly nocturia. This may be highly bothersome with a major impact on the patient's quality of life. In the past, nocturia is seldom reported as a single, physiologically distinct endpoint, and little is known about its etiology. It is assumed that in addition to dose-volume parameters and patient- and therapy-related factors, a genetic component contributes to the development of radiation-induced damage. In this study, we investigated the association among dosimetric, clinical, and TGF{beta}1 polymorphisms and the development of acute radiation-induced nocturia in prostate cancer patients. Methods and Materials: Data were available for 322 prostate cancer patients treated with primary or postoperative intensity modulated radiation therapy (IMRT). Five genetic markers in the TGF{beta}1 gene (-800 G>A, -509 C>T, codon 10 T>C, codon 25 G>C, g.10780 T>G), and a high number of clinical and dosimetric parameters were considered. Toxicity was scored using an symptom scale developed in-house. Results: Radical prostatectomy (PT and codon 10 T>C are identified as factors involved in the development of acute radiation-induced nocturia. These findings may contribute to the research on prediction of late nocturia after IMRT for prostate cancer.

De Langhe, Sofie, E-mail: Sofie.DeLanghe@UGent.be [Department of Basic Medical Sciences, Ghent University, Gent (Belgium); De Ruyck, Kim [Department of Basic Medical Sciences, Ghent University, Gent (Belgium)] [Department of Basic Medical Sciences, Ghent University, Gent (Belgium); Ost, Piet; Fonteyne, Valerie [Department of Radiation Oncology, Ghent University Hospital, Gent (Belgium)] [Department of Radiation Oncology, Ghent University Hospital, Gent (Belgium); Werbrouck, Joke [Department of Basic Medical Sciences, Ghent University, Gent (Belgium)] [Department of Basic Medical Sciences, Ghent University, Gent (Belgium); De Meerleer, Gert; De Neve, Wilfried [Department of Radiation Oncology, Ghent University Hospital, Gent (Belgium)] [Department of Radiation Oncology, Ghent University Hospital, Gent (Belgium); Thierens, Hubert [Department of Basic Medical Sciences, Ghent University, Gent (Belgium)] [Department of Basic Medical Sciences, Ghent University, Gent (Belgium)

2013-02-01T23:59:59.000Z

77

Radiation-Induced Damage to Microstructure of Parotid Gland: Evaluation Using High-Resolution Magnetic Resonance Imaging  

SciTech Connect

Purpose: To elucidate the radiation-induced damage to the microstructure of the parotid gland using high-resolution magnetic resonance imaging. Methods and Materials: High-resolution magnetic resonance imaging of the parotid gland was performed before radiotherapy (RT) and during the RT period or {<=}3 weeks after RT completion for 12 head-and-neck cancer patients using a 1.5-T scanner with a microscopy coil. The maximal cross-sectional area of the gland was evaluated, and changes in the internal architecture of the gland were assessed both visually and quantitatively. Results: Magnetic resonance images were obtained at a median parotid gland dose of 36 Gy (range, 11-64). According to the quantitative analysis, the maximal cross-sectional area of the gland was reduced, the width of the main duct was narrowed, and the intensity ratio of the main duct lumen to background was significantly decreased after RT (p <.0001). According to the visual assessment, the width of the main duct tended to narrow and the contrast of the duct lumen tended to be decreased, but no significant differences were noted. The visibility of the duct branches was unclear in 10 patients (p = .039), and the septum became dense in 11 patients (p = .006) after RT. Conclusion: High-resolution magnetic resonance imaging is a noninvasive method of evaluating radiation-induced changes to the internal architecture of the parotid gland. Morphologic changes in the irradiated parotid gland were demonstrated during the RT course even when a relatively small dose was delivered to the gland.

Kan, Tomoko, E-mail: tkan@grape.med.tottori-u.ac.j [Department of Radiology, Tottori University Faculty of Medicine, Yonago, Tottori (Japan); Kodani, Kazuhiko; Michimoto, Koichi; Fujii, Shinya; Ogawa, Toshihide [Department of Radiology, Tottori University Faculty of Medicine, Yonago, Tottori (Japan)

2010-07-15T23:59:59.000Z

78

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

79

Radiation-induced cancer and its modifying factor among A-bomb survivors  

SciTech Connect

The Atomic Bomb Casualty Commission (ABCC) and its successor, the Radiation Effects Research Foundation, have conducted a long-term follow-up study of a cohort of 120,000 atomic bomb (A-bomb) survivors and non-exposed controls since 1950. The most recent findings regarding cancer mortality and incidence in this cohort can be briefly summarized as follows: 1) An increase in leukemia mortality among A-bomb survivors peaked 5-6 years after the bombing and has decreased with time thereafter. In addition to leukemia, the incidence of cancer of the lung, breast, esophagus, stomach, colon, thyroid, ovary, urinary tract, and multiple myeloma increases with dose. At present, there is no indication of an increase in cancer of the rectum or uterus among A-bomb survivors. In general, radiation-induced solid cancers begin to appear after the age at which they are normally prone to develop, and have continued to increase with time in proportion to the natural increase in mortality of the control group. 2) There are factors which modify the effects of radiation, such as age at the time of bombing (ATB) and sex. Sensitivity to radiation, in terms of cancer induction, is higher for persons who were young ATB in general, than for those who were older ATB. 3) There was no increase in childhood cancer among those exposed while in utero, but there is a recent indication of an increase in cancer incidence among these persons as they age. 4) There seems to be no interaction in a multiplicative way between radiation and smoking and lung cancer induction.

Kato, H.

1987-01-01T23:59:59.000Z

80

Dose-dependent transitions in Nrf2-mediated adaptive response and related stress responses to hypochlorous acid in mouse macrophages  

Science Conference Proceedings (OSTI)

Hypochlorous acid (HOCl) is potentially an important source of cellular oxidative stress. Human HOCl exposure can occur from chlorine gas inhalation or from endogenous sources of HOCl, such as respiratory burst by phagocytes. Transcription factor Nrf2 is a key regulator of cellular redox status and serves as a primary source of defense against oxidative stress. We recently demonstrated that HOCl activates Nrf2-mediated antioxidant response in cultured mouse macrophages in a biphasic manner. In an effort to determine whether Nrf2 pathways overlap with other stress pathways, gene expression profiling was performed in RAW 264.7 macrophages exposed to HOCl using whole genome mouse microarrays. Benchmark dose (BMD) analysis on gene expression data revealed that Nrf2-mediated antioxidant response and protein ubiquitination were the most sensitive biological pathways that were activated in response to low concentrations of HOCl (< 0.35 mM). Genes involved in chromatin architecture maintenance and DNA-dependent transcription were also sensitive to very low doses. Moderate concentrations of HOCl (0.35 to 1.4 mM) caused maximal activation of the Nrf2 pathway and innate immune response genes, such as IL-1{beta}, IL-6, IL-10 and chemokines. At even higher concentrations of HOCl (2.8 to 3.5 mM) there was a loss of Nrf2-target gene expression with increased expression of numerous heat shock and histone cluster genes, AP-1-family genes, cFos and Fra1 and DNA damage-inducible Gadd45 genes. These findings confirm an Nrf2-centric mechanism of action of HOCl in mouse macrophages and provide evidence of interactions between Nrf2, inflammatory, and other stress pathways.

Woods, Courtney G. [Division of Computational Biology, Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); ExxonMobil Biomedical Sciences Incorporated, Annandale, NJ 08801 (United States); Fu Jingqi; Xue Peng; Hou Yongyong [Division of Translational Biology, Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China); Pluta, Linda J.; Yang Longlong; Zhang Qiang; Thomas, Russell S.; Andersen, Melvin E. [Division of Computational Biology, Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Pi Jingbo [Division of Translational Biology, Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States)], E-mail: jpi@thehamner.org

2009-07-01T23:59:59.000Z

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81

Radiation Leukaemongenesis at Low Doses  

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

Leukaemongenesis at Low Doses Leukaemongenesis at Low Doses Simon Bouffler Health Protection Agency Abstract Myeloid leukaemias feature prominently among the cancers associated with human exposures to ionising radiation. The CBA mouse model of radiation-induced acute myeloid leukaemia (AML) has been used extensively for both quantitative and mechanistic studies. Loss of genetic material from chromosome 2 (chr2) is known to be associated with most radiation-induced AMLs. AML develops in CBA mice exposed to X- or γ-radiation, after a mean latency period of 18 months, with a maximal incidence of approximately 25% at 3Gy. A strong candidate AML-suppressor gene located within the commonly deleted region of chr2 has been identified, Sƒpil/PU.1. This gene suffers hemizygous loss and specific

82

Reproductive Status at First Diagnosis Influences Risk of Radiation-Induced Second Primary Contralateral Breast Cancer in the WECARE Study  

Science Conference Proceedings (OSTI)

Purpose: Our study examined whether reproductive and hormonal factors before, at the time of, or after radiation treatment for a first primary breast cancer modify the risk of radiation-induced second primary breast cancer. Methods and Materials: The Women's Environmental, Cancer and Radiation Epidemiology (WECARE) Study is a multicenter, population-based study of 708 women (cases) with asynchronous contralateral breast cancer (CBC) and 1399 women (controls) with unilateral breast cancer. Radiotherapy (RT) records, coupled with anthropomorphic phantom simulations, were used to estimate quadrant-specific radiation dose to the contralateral breast for each patient. Rate ratios (RR) and 95% confidence intervals (CI) were computed to assess the relationship between reproductive factors and risk of CBC. Results: Women who were nulliparous at diagnosis and exposed to {>=}1 Gy to the contralateral breast had a greater risk for CBC than did matched unexposed nulliparous women (RR = 2.2; 95% CI, 1.2-4.0). No increased risk was seen in RT-exposed parous women (RR = 1.1; 95% CI, 0.8-1.4). Women treated with RT who later became pregnant (8 cases and 9 controls) had a greater risk for CBC (RR = 6.0; 95% CI, 1.3-28.4) than unexposed women (4 cases and 7 controls) who also became pregnant. The association of radiation with risk of CBC did not vary by number of pregnancies, history of breastfeeding, or menopausal status at the time of first breast cancer diagnosis. Conclusion: Nulliparous women treated with RT were at an increased risk for CBC. Although based on small numbers, women who become pregnant after first diagnosis also seem to be at an increased risk for radiation-induced CBC.

Brooks, Jennifer D., E-mail: brooksj@mskcc.org [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Boice, John D. [International Epidemiology Institute, Rockville, MD and Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN (United States)] [International Epidemiology Institute, Rockville, MD and Department of Medicine, Vanderbilt Epidemiology Center, Vanderbilt-Ingram Cancer Center, Vanderbilt School of Medicine, Nashville, TN (United States); Stovall, Marilyn [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Reiner, Anne S. [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Bernstein, Leslie [Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute and City of Hope Comprehensive Cancer Center, Duarte, CA (United States)] [Division of Cancer Etiology, Department of Population Sciences, Beckman Research Institute and City of Hope Comprehensive Cancer Center, Duarte, CA (United States); John, Esther M. [Cancer Prevention Institute of California, Fremont, CA, and Stanford University School of Medicine and Stanford Cancer Institute, Stanford, CA (United States)] [Cancer Prevention Institute of California, Fremont, CA, and Stanford University School of Medicine and Stanford Cancer Institute, Stanford, CA (United States); Lynch, Charles F. [Department of Epidemiology, University of Iowa, Iowa City, IA (United States)] [Department of Epidemiology, University of Iowa, Iowa City, IA (United States); Mellemkjaer, Lene [Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen (Denmark)] [Institute of Cancer Epidemiology, Danish Cancer Society, Copenhagen (Denmark); Knight, Julia A. [Dalla Lana School of Public Health, University of Toronto and Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario (Canada)] [Dalla Lana School of Public Health, University of Toronto and Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario (Canada); Thomas, Duncan C.; Haile, Robert W. [Department of Preventive Medicine, University of Southern California, Los Angeles, CA (United States)] [Department of Preventive Medicine, University of Southern California, Los Angeles, CA (United States); Smith, Susan A. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Capanu, Marinela; Bernstein, Jonine L. [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Shore, Roy E. [Department of Environmental Medicine, New York University, New York, NY (United States) [Department of Environmental Medicine, New York University, New York, NY (United States); Radiation Effects Research Foundation, Hiroshima (Japan)

2012-11-15T23:59:59.000Z

83

Effect of low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice  

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

low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice K. Gott, V. Gonzales, M. Makvandi, N. Kikendall, A. Monier, E. Maloy, C. Rietz, B. Scott and J. Wilder. Lovelace Respiratory Research Institute, Albuquerque, NM Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response (Nowosielska et al., 2006), presumably via epigenetic pathways (Scott et al., 2009) and has been implicated as suppressing both alpha-radiation-induced and smoking-related lung cancer (Scott et al. 2009). One of the hypothesized adaptive-response mechanisms by which LDR does so is by activating immune cell function in the lung, which would then increase their anti-cancer surveillance

84

Dislocation vs. production bias revisited with account of radiation-induced emission bias I. Void swelling under electron and light ion irradiation  

SciTech Connect

Early experimental data on void swelling in electron-irradiated materials disagree with the dislocation bias models based on the dislocation-point defect elastic interactions. Later this became one of the reasons that prompted the development of models based on production bias (PBM) as the main driver for swelling, which assumed that the dislocation bias was much lower than that predicted by theory. However, the PBM in its present form fails to account for important and common observations: the indefinite void growth often observed under cascade irradiation and the swelling saturation observed under high dose irradiation and in void lattices. In this paper we show that these contradictions can be naturally resolved in the framework of the rate theory modified with account of the radiation-induced vacancy emission from extended defects, such as voids, dislocations and grain boundaries. The modified rate theory agrees well with the experimental data, which proves that original dislocation bias should be used in rate theory models in different irradiation. The modified theory predictions include (but not limited to) the radiation-induced annealing of voids, swelling saturation under high dose irradiation, generally, and in void lattices, in particular.

Dubinko, Volodymyr; Hu, Shenyang Y.; Li, Yulan; Henager, Charles H.; Kurtz, Richard J.

2012-07-19T23:59:59.000Z

85

Detecting Radiation-Induced Injury Using Rapid 3D Variogram Analysis of CT Images of Rat Lungs  

SciTech Connect

A new heterogeneity analysis approach to discern radiation-induced lung damage was tested on CT images of irradiated rats. The method, combining octree decomposition with variogram analysis, demonstrated a significant correlation with radiation exposure levels, whereas conventional measurements and pulmonary function tests did not. The results suggest the new approach may be highly sensitive for assessing even subtle radiation-induced changes

Jacob, Rick E.; Murphy, Mark K.; Creim, Jeffrey A.; Carson, James P.

2013-10-01T23:59:59.000Z

86

Radiation-induced changes in the cuticular hydrocarbons of the granary weevil and their relationship to desiccation and adult mortality  

Science Conference Proceedings (OSTI)

Radiation from the nuclear waste products, such as Cesium-137, offers a scope and could be used for large scale disinfestation of grain. It is known that 0.15 to 0.20 kGy dose of gamma radiation is sufficient to kill insects in grain and grain products. However, the mode of action (in terms of lethal effects) is not understood. The purpose of this project, therefore, is to study the ways in which gamma radiation causes death in the granary weevil. Sitophilus granarius (L.) is a major and cosmopolitan pest of stored grain all over the world. Radiation damage, in particular the specific effects on the physiology of the insects exposed to radiation has been elucidated. In stored grain insects, conservation of water is a critical factor for their survival. Epicuticular hydrocarbons play an important role in water proofing. The laboratory rearing of the granary weevil was standardized so that large numbers of weevils of known ages could be produced for experimentation. Stock cultures were maintained at 27 {plus minus} 2{degree}C and 65 {plus minus} 5% R.H. Tests with various age groups (adults) and different doses of gamma radiation indicate that lethal effects are both age and dose related. Younger weevils, in general, survive for a longer period after irradiation compared to older weevils. Complete mortality results within about two weeks after exposure to gamma radiation at dose of 0.15 kGy or above. Data on wet and dry weights of the weevils kept at different (low, medium and higher) levels of humidity after irradiation indicate that gamma radiation induces greater water loss leading to desiccation and early death. Low humidity environment (17% R.H.) greatly accelerates lethal effects.

Sriharan, S. (Selma Univ., AL (USA). Div. of Natural and Applied Sciences)

1989-07-01T23:59:59.000Z

87

Normal Tissue Complication Probability Modeling of Radiation-Induced Hypothyroidism After Head-and-Neck Radiation Therapy  

Science Conference Proceedings (OSTI)

Purpose: To determine the dose-response relationship of the thyroid for radiation-induced hypothyroidism in head-and-neck radiation therapy, according to 6 normal tissue complication probability models, and to find the best-fit parameters of the models. Methods and Materials: Sixty-five patients treated with primary or postoperative radiation therapy for various cancers in the head-and-neck region were prospectively evaluated. Patient serum samples (tri-iodothyronine, thyroxine, thyroid-stimulating hormone [TSH], free tri-iodothyronine, and free thyroxine) were measured before and at regular time intervals until 1 year after the completion of radiation therapy. Dose-volume histograms (DVHs) of the patients' thyroid gland were derived from their computed tomography (CT)-based treatment planning data. Hypothyroidism was defined as increased TSH (subclinical hypothyroidism) or increased TSH in combination with decreased free thyroxine and thyroxine (clinical hypothyroidism). Thyroid DVHs were converted to 2 Gy/fraction equivalent doses using the linear-quadratic formula with {alpha}/{beta} = 3 Gy. The evaluated models included the following: Lyman with the DVH reduced to the equivalent uniform dose (EUD), known as LEUD; Logit-EUD; mean dose; relative seriality; individual critical volume; and population critical volume models. The parameters of the models were obtained by fitting the patients' data using a maximum likelihood analysis method. The goodness of fit of the models was determined by the 2-sample Kolmogorov-Smirnov test. Ranking of the models was made according to Akaike's information criterion. Results: Twenty-nine patients (44.6%) experienced hypothyroidism. None of the models was rejected according to the evaluation of the goodness of fit. The mean dose model was ranked as the best model on the basis of its Akaike's information criterion value. The D{sub 50} estimated from the models was approximately 44 Gy. Conclusions: The implemented normal tissue complication probability models showed a parallel architecture for the thyroid. The mean dose model can be used as the best model to describe the dose-response relationship for hypothyroidism complication.

Bakhshandeh, Mohsen [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hashemi, Bijan, E-mail: bhashemi@modares.ac.ir [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Mahdavi, Seied Rabi Mehdi [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)] [Department of Medical Physics, Faculty of Medical Sciences, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nikoofar, Alireza; Vasheghani, Maryam [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)] [Department of Radiation Oncology, Hafte-Tir Hospital, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Kazemnejad, Anoshirvan [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)] [Department of Biostatistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

2013-02-01T23:59:59.000Z

88

Radiation-Induced Demagnetization of Nd-Fe-B Permanent Magnets  

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

LS-290 LS-290 Radiation-Induced Demagnetization of Nd-Fe-B Permanent Magnets J. Alderman and P.K. Job APS Operations Division Advanced Photon Source Argonne National Laboratory R.C. Martin, C.M. Simmons, and G.D. Owen Californium User Facility for Neutron Science Chemical Technology Division Oak Ridge National Laboratory J. Puhl Ionizing Radiation Division National Institute of Standards and Technology November 2000 work sponsored by U.S. DEPARTMENT OF ENERGY Office of Energy Research 1 Radiation-Induced Demagnetization of Nd-Fe-B Permanent Magnets J. Alderman and P.K. Job APS Operations Division Advanced Photon Source Argonne National Laboratory R.C. Martin, C.M. Simmons, and G. D. Owen Californium User Facility for Neutron Science

89

Quantitative, non-invasive imaging of radiation-induced DNA double strand breaks in vivo  

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

Quantitative, non-invasive imaging of radiation-induced DNA double strand breaks in vivo Quantitative, non-invasive imaging of radiation-induced DNA double strand breaks in vivo Wenrong Li 1, , Fang Li 1 , Qian Huang 1 , Jingping Shen 1 , Frank Wolf 1 , Yujun He 1 , Xinjian Liu 1 , Y. Angela Hu 1 , Joel. S. Bedford 5 , and Chuan-Yuan Li 1,2,* Departments of 1 Radiation Oncology, 2 Pharmacology, University of Colorado School of Medicine, Aurora, Colorado, USA; 3 Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA DNA double strand breaks are a major form of DNA damage and a key mechanism through which radiotherapy and some chemotherapeutic agents kill cancer cells. Despite its importance, measuring DNA double strand breaks is still a tedious task that is normally carried out by gel electrophoresis or immunofluorescence staining. Here we report a novel approach to image and

90

Radiation-induced transient attenuation of optical fibers at 800 and 1300 nm  

SciTech Connect

Radiation-induced absorption in optical fibers has been a subject of considerable interest throughout the world. As availability and applications of fibers have evolved from ''first window'' systems operating near 850 nm to ''second window'' systems near 1300 nm, interest in wavelength dependence of radiation effects in optical fibers has similarly evolved. The present work summarizes second-window, radiation-induced transient absorption measurements in optical fibers for times shorter than 5 ..mu..s. Comparisons to first window data for these fibers are also presented. Only high purity silica fibers with low-OH concentrations were used in the present study to avoid the large OH absorption band in this region. This paper also collects first window data on several high-OH optical fibers.

Looney, L.D.; Lyons, P.B.

1987-01-01T23:59:59.000Z

91

Relation between measurable and principal characteristics of radiation-induced shape-change of graphite  

E-Print Network (OSTI)

On the basis of studies of radiation-induced shape-change of reactor graphite GR-280, through the series of measurements of samples with different orientation of cutting with respect to the direction of extrusion, a conclusion is made about the existence of polycrystal substructural elements - domains. Domains, like graphite as a whole, possess the property of transverse isotropy, but have different amplitudes of shape-change and random orientations of the axes of axial symmetry. The model of graphite, constructed on the basis of the concept of domains allowed to explain from a unified point of view most of existing experimental data. It is shown that the presence of the disoriented domain structure leads to the development of radiation-induced stresses and to the dependence of the shape-change on the size of graphite samples. We derive the relation between the shape-change of finite size samples and the actual shape-change of macro-graphite.

M. V. Arjakov; A. V. Subbotin; S. V. Panyukov; O. V. Ivanov; A. S. Pokrovskii; D. V. Kharkov

2011-04-12T23:59:59.000Z

92

Association of P53 and ATM Polymorphisms With Risk of Radiation-Induced Pneumonitis in Lung Cancer Patients Treated With Radiotherapy  

Science Conference Proceedings (OSTI)

Purpose: Radiation-induced pneumonitis (RP) is the most common dose-limiting complication in lung cancer patients treated with radiotherapy. Accumulating evidence indicates that P53 and the ataxia telangiectasia-mutated protein (ATM)-dependent signaling response cascade play a crucial role in radiation-induced diseases. Consistent with this, our previous study showed that a functional genetic ATM polymorphism was associated with increased RP risk. Methods and Materials: To evaluate the role of genetic P53 polymorphism in RP, we analyzed the P53 Arg72Pro polymorphism in a cohort including 253 lung cancer patients receiving thoracic irradiation. Results: We found that the P53 72Arg/Arg genotype was associated with increased RP risk compared with the 72Pro/Pro genotype. Furthermore, the P53 Arg72Pro and ATM -111G>A polymorphisms display an additive combination effect in intensifying the risk of developing RP. The cross-validation test showed that 63.2% of RP cases can be identified by P53 and ATM genotypes. Conclusions: These results indicate that genetic polymorphisms in the ATM-P53 pathway influence susceptibility to RP and genotyping P53 and ATM polymorphisms might help to identify patients susceptible to developing RP when receiving radiotherapy.

Yang Ming [Departments of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Key Laboratory for Carcinogenesis and Cancer Prevention, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhang Li [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Bi Nan; Ji Wei [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Tan Wen [Departments of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Key Laboratory for Carcinogenesis and Cancer Prevention, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhao Lujun [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Yu Dianke; Wu Chen [Departments of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Key Laboratory for Carcinogenesis and Cancer Prevention, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Wang Luhua [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

2011-04-01T23:59:59.000Z

93

Introduction of bifunctional group onto MWNT by radiation-induced graft polymerization and its use as biosensor-supporting materials  

Science Conference Proceedings (OSTI)

A biosensor comprising tyrosinase immobilized on bifunctionalized multiwalled carbon nanotube (MWNT) supports was prepared for the detection of phenolic compounds in drinks such as red wine and juices. The MWNT supports were prepared by radiation-induced ...

Yu-Jin Lee; Da-Jung Chung; Sang-Hyub Oh; Seong-Ho Choi

2012-01-01T23:59:59.000Z

94

Low Dose Radiation Research Program: Slide Shows  

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

Dose Health Effects of Radiation Health Effects of Radiation Adaptive Response to Low Dose Radiation PDF Background Radiation PDF Bystander Effects PDF Dirty Bombs PDF DNA Damage...

95

Low Dose Radiation Research Program: Genetic Factors Affecting  

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

Affecting Susceptibility to Low-Dose Radiation Affecting Susceptibility to Low-Dose Radiation William F. Morgan Pacific Northwest National Laboratory Why This Project The short-term effects of high doses of ionizing radiation on cellular responses are relatively well understood. Less clear are the long-term consequences of exposure to low dose/low dose-rate radiation and the effects of radiation exposure on the progeny of surviving cells. If a cell survives radiation, it is generally thought to have repaired all the radiation-induced insults and be capable of a "normal healthy life". At a certain frequency, however, we have found that some cells surviving radiation grow normally, but will rearrange their genetic material during time in culture. We call this radiation-induced genomic instability. Many

96

Stress-related phenomena in transient radiation-induced absorption in optical fibers  

SciTech Connect

The optical properties of materials can be modified by exposure to radiation and research to investigate these radiation-induced phenomena has intensified over the last several decades. The advent of optical fiber technology and the many applications of optical fiber for information transmission have sharply increased the interest in these investigations. Optical fibers present a long optical transmission path and that path may traverse different adverse environments, including radiation areas. The long tranmission path provides increased potential for interactions between the optical information signal and the optical medium. 10 refs., 10 figs.

Looney, L.D.; Lyons, P.B.; Kelly, R.E.

1988-01-01T23:59:59.000Z

97

Transient radiation-induced absorption in materials for the DOI laser  

Science Conference Proceedings (OSTI)

This is the final report on a series of experiments concerned with transient radiation-induced absorption in materials for a Cr,Nd:GSGG laser. Both the Sandia National Laboratories SPR III pulsed reactor and the Hermes III pulsed X-ray machine are used as radiation sources. The time dependence and the magnitude of the induced absorption in filter glasses and in doped and undoped LiNbO{sub 3} Q-switch materials have been measured. Gain has been observed in Cr,Nd:GSGG, the laser medium, when it is irradiated by X-rays.

Brannon, P.J.

1995-01-01T23:59:59.000Z

98

Effects of Adenovirus-Mediated Delivery of the Human Hepatocyte Growth Factor Gene in Experimental Radiation-Induced Heart Disease  

SciTech Connect

Purpose: Irradiation to the heart may lead to late cardiovascular complications. The purpose of this study was to investigate whether adenovirus-mediated delivery of the human hepatocyte growth factor gene could reduce post-irradiation damage of the rat heart and improve heart function. Methods and Materials: Twenty rats received single-dose irradiation of 20 Gy gamma ray locally to the heart and were randomized into two groups. Two weeks after irradiation, these two groups of rats received Ad-HGF or mock adenovirus vector intramyocardial injection, respectively. Another 10 rats served as sham-irradiated controls. At post-irradiation Day 120, myocardial perfusion was tested by myocardial contrast echocardiography with contrast agent injected intravenously. At post-irradiation Day 180, cardiac function was assessed using the Langendorff technique with an isolated working heart model, after which heart samples were collected for histological evaluation. Results: Myocardial blood flow was significantly improved in HGF-treated animals as measured by myocardial contrast echocardiography at post-irradiation Day 120 . At post-irradiation Day 180, cardiac function was significantly improved in the HGF group compared with mock vector group, as measured by left ventricular peak systolic pressure (58.80 +- 9.01 vs. 41.94 +- 6.65 mm Hg, p < 0.05), the maximum dP/dt (5634 +- 1303 vs. 1667 +- 304 mm Hg/s, p < 0.01), and the minimum dP/dt (3477 +- 1084 vs. 1566 +- 499 mm Hg/s, p < 0.05). Picrosirius red staining analysis also revealed a significant reduction of fibrosis in the HGF group. Conclusion: Based on the study findings, hepatocyte growth factor gene transfer can attenuate radiation-induced cardiac injury and can preserve cardiac function.

Hu Shunying; Chen Yundai [Department of Cardiology, Chinese PLA General Hospital, Beijing (China); Li Libing [Department of Cardiovascular Surgery, Chinese PLA General Hospital, Beijing (China); Chen Jinlong; Wu Bin [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing (China); Zhou, Xiao; Zhi Guang [Department of Cardiology, Chinese PLA General Hospital, Beijing (China); Li Qingfang; Wang Rongliang; Duan Haifeng; Guo Zikuan; Yang Yuefeng; Xiao Fengjun [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing (China); Wang Hua, E-mail: wanghua@nic.bmi.ac.c [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing (China); Wang Lisheng [Department of Experimental Hematology, Beijing Institute of Radiation Medicine, Beijing (China)

2009-12-01T23:59:59.000Z

99

Pilot Study Of Impedance-controlled Microcurrent Therapy For Managing Radiation-induced Fibrosis In Head-and-neck Cancer Patients  

E-Print Network (OSTI)

Pilot Study Of Impedance-controlled Microcurrent Therapy For Managing Radiation-induced Fibrosis In Head-and-neck Cancer Patients

Lennox, A J

2002-01-01T23:59:59.000Z

100

Quantitative effect of combined chemotherapy and fractionated radiotherapy on the incidence of radiation-induced lung damage: A prospective clinical study  

SciTech Connect

The objective of this work was to assess the incidence of radiological changes compatible with radiation-induced lung damage as determined by computed tomography (CT), and subsequently calculate the dose effect factors (DEF) for specified chemotherapeutic regimens. Radiation treatments were administered once daily, 5 days-per-week. Six clinical protocols were evaluated: ABVD (adriamycin, bleomycin, vincristine, and DTIC) followed by 35 Gy in 20 fractions; MOPP (nitrogen mustard, vincristine, procarbazine, and prednisone) followed by 35 Gy in 20; MOPP/ABVD followed by 35 Gy in 20; CAV (cyclophosphamide, adriamycin, and vincristine) followed by 25 Gy in 10; and 5-FU (5-fluorouracil) concurrent with either 50-52 Gy in 20-21 or 30-36 Gy in 10-15 fractions. CT examinations were taken before and at predetermined intervals following radiotherapy. CT evidence for the development of radiation-induced damage was defined as an increase in lung density within the irradiated volume. The radiation dose to lung was calculated using a CT-based algorithm to account for tissue inhomogeneities. Different fractionation schedules were converted using two isoeffect models, the estimated single dose (ED) and the normalized total dose (NTD). The actuarial incidence of radiological pneumonitis was 71% for the ABVD, 49% for MOPP, 52% for MOPP/ABVD, 67% for CAV, 73% for 5-FU radical, and 58% for 5-FU palliative protocols. Depending on the isoeffect model selected and the method of analysis, the DEF was 1.11-1.14 for the ABVD, 0.96-0.97 for the MOPP, 0.96-1.02 for the MOPP/ABVD, 1.03-1.10 for the CAV, 0.74-0.79 for the 5-FU radical, and 0.94 for the 5-FU palliative protocols. DEF were measured by comparing the incidence of CT-observed lung damage in patients receiving chemotherapy and radiotherapy to those receiving radiotherapy alone. The addition of ABVD or CAV appeared to reduce the tolerance of lung to radiation. 40 refs., 3 figs., 3 tabs.

Mah, K.; Van Dyk, J.; Braban, L.E.; Hao, Y.; Keane, T.J. (Univ. of Toronto, Ontario (Canada)); Poon, P.Y. (Univ. of British Columbia (Canada))

1994-02-01T23:59:59.000Z

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101

Combining Physical and Biologic Parameters to Predict Radiation-Induced Lung Toxicity in Patients With Non-Small-Cell Lung Cancer Treated With Definitive Radiation Therapy  

SciTech Connect

Purpose: To investigate the plasma dynamics of 5 proinflammatory/fibrogenic cytokines, including interleukin-1beta (IL-1{beta}), IL-6, IL-8, tumor necrosis factor alpha (TNF-{alpha}), and transforming growth factor beta1 (TGF-{beta}1) to ascertain their value in predicting radiation-induced lung toxicity (RILT), both individually and in combination with physical dosimetric parameters. Methods and Materials: Treatments of patients receiving definitive conventionally fractionated radiation therapy (RT) on clinical trial for inoperable stages I-III lung cancer were prospectively evaluated. Circulating cytokine levels were measured prior to and at weeks 2 and 4 during RT. The primary endpoint was symptomatic RILT, defined as grade 2 and higher radiation pneumonitis or symptomatic pulmonary fibrosis. Minimum follow-up was 18 months. Results: Of 58 eligible patients, 10 (17.2%) patients developed RILT. Lower pretreatment IL-8 levels were significantly correlated with development of RILT, while radiation-induced elevations of TGF-ss1 were weakly correlated with RILT. Significant correlations were not found for any of the remaining 3 cytokines or for any clinical or dosimetric parameters. Using receiver operator characteristic curves for predictive risk assessment modeling, we found both individual cytokines and dosimetric parameters were poor independent predictors of RILT. However, combining IL-8, TGF-ss1, and mean lung dose into a single model yielded an improved predictive ability (P<.001) compared to either variable alone. Conclusions: Combining inflammatory cytokines with physical dosimetric factors may provide a more accurate model for RILT prediction. Future study with a larger number of cases and events is needed to validate such findings.

Stenmark, Matthew H. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Cai Xuwei [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States) [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Radiation Oncology, Shanghai Cancer Hospital, Fudan University, Shanghai (China); Shedden, Kerby [Department of Biostatistics, University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Biostatistics, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Hayman, James A. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Yuan Shuanghu [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States) [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Radiation Oncology, Shangdong Cancer Hospital, Jinan (China); Ritter, Timothy [Veterans Affairs Medical Center, Ann Arbor, Michigan (United States)] [Veterans Affairs Medical Center, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Kong Fengming, E-mail: fengkong@med.umich.edu [Department of Radiation Oncology, University of Michigan Medical Center, Ann Arbor, Michigan (United States); Veterans Affairs Medical Center, Ann Arbor, Michigan (United States)

2012-10-01T23:59:59.000Z

102

Radiation Induced Chromatid-type Aberrations after Irradiation of Late-S/G2  

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

Induced Chromatid-type Aberrations after Irradiation of Late-S/G2 Induced Chromatid-type Aberrations after Irradiation of Late-S/G2 Cells: Roles of Homologous Recombination and Non-Homologous End Joining Joel Bedford Colorado State University Abstract There has been considerable discussion, with some data reported, addressing the question of the relative contributions of non-homologous end joining (NHEJ) and homologous recombinational repair (HRR) on the repair or rejoining of radiation-induced DNA double strand breaks, especially in relation to their operation during the cell cycle. Reports have included studies on chromosomal aberration induction in G1/G0 cells defective in NHEJ or A-T cells, for example, but relatively little on S/G2 cells and especially on mutants defective in HRR. The broad biological importance of

103

Consequences of low dose irradiation in the CNS  

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Consequences of low dose irradiation in the CNS Consequences of low dose irradiation in the CNS Bertrand Tseng University of California Abstract Radiation-induced oxidative stress can impact the physiologic function of multipotent neural stem and precursor cells by activating redox-sensitive signaling cascades that can alter radiosensitivity, mitochondrial function, and cell fate. Many of these signaling pathways depend on the nature, magnitude and duration of the specific reactive species involved, features that dictate in large part whether radiation-induced changes are harmful or beneficial to the organism. We have shown that acute low dose irradiation (2-20 cGy) can elicit significant increases in reactive oxygen (ROS) and nitrogen (RNS) species over several days to weeks. These redox changes can

104

Radiation-induced attenuation of high-OH optical fibers after hydrogen treatment in the presence of ionizing radiation  

DOE Green Energy (OSTI)

High purity, high-OH, optical fibers were irradiated in a hydrogen atmosphere to explore hydrogen binding into defects created by the ionizing radiation. Significant improvements in subsequent measurements of radiation-induced attenuation were observed. 18 refs., 4 figs., 2 tabs.

Lyons, P.B; Looney, L.D.

1991-01-01T23:59:59.000Z

105

Contribution of endogenous and exogenous damage to the total radiation-induced damage in the bacterial spore  

Science Conference Proceedings (OSTI)

Radical scavengers such as polyethylene glycol 4000 and bovine albumin have been used to define the contribution of exogenous and endogenous damage to the total radiation-induced damage in aqueous buffered suspensions of Bacillus pumilus spores. The results indicate that this damage in the bacterial spore is predominantly endogenous.

Jacobs, G.P.; Samuni, A.; Czapski, G.

1980-01-01T23:59:59.000Z

106

Epidermal growth factor receptor expression in radiation-induced dog lung tumors by immunocytochemical localization  

SciTech Connect

In studies to determine the role of growth factors in radiation-induced lung cancer, epidermal growth factor (EGFR) expression was examined by immunocytochemistry in 51 lung tumors from beagle dogs exposed to inhaled plutonium; 21 of 51 (41%) tumors were positive for EGFR. The traction of tumors positive for EGFR and the histological type of EGFR-positive tumors in the plutonium-exposed dogs were not different from spontaneous dog lung tumors, In which 36% were positive for EGFR. EGFR involvement in Pu-induced lung tumors appeared to be similar to that in spontaneous lung tumors. However, EGFR-positive staining was observed in only 1 of 16 tumors at the three lowest Pu exposure levels, compared to 20 of 35 tumors staining positive at the two highest Pu exposure levels. The results in dogs were in good agreement with the expression of EGFR reported in human non-small cell carcinoma of the lung, suggesting that Pu-induced lung tumors in the dog may be a suitable animal model to investigate the role of EGFR expression in lung carcinogenesis. In humans, EGFR expression in lung tumors has been primarily related to histological tumor types. In individual dogs with multiple primary lung tumors, the tumors were either all EGFR positive or EGFR negative, suggesting that EGFR expression may be related to the response of the individual dog as well as to the histological type of tumor.

Leung, F.L.; Park, J.F.; Dagle, G.E.

1993-06-01T23:59:59.000Z

107

ATM Polymorphisms Are Associated With Risk of Radiation-Induced Pneumonitis  

SciTech Connect

Purpose: Since the ataxia telangiectasia mutated (ATM) protein plays crucial roles in repair of double-stranded DNA breaks, control of cell cycle checkpoints, and radiosensitivity, we hypothesized that variations in this gene might be associated with radiation-induced pneumonitis (RP). Methods and Materials: A total of 253 lung cancer patients receiving thoracic irradiation between 2004 and 2006 were included in this study. Common Terminology Criteria for Adverse Events version 3.0 was used to grade RP. Five haplotype-tagging single nucleotide polymorphisms (SNPs) in the ATM gene were genotyped using DNA from blood lymphocytes. Hazard ratios (HRs) and 95% confidence intervals (CIs) of RP for genotypes were computed by the Cox model, adjusted for clinical factors. The function of the ATM SNP associated with RP was examined by biochemical assays. Results: During the median 22-month follow-up, 44 (17.4%) patients developed grade {>=} 2 RP. In multivariate Cox regression models adjusted for other clinical predictors, we found two ATM variants were independently associated with increased RP risk. They were an 111G > A) polymorphism (HR, 2.49; 95% CI, 1.07-5.80) and an ATM 126713G > A polymorphism (HR, 2.47; 95% CI, 1.16-5.28). Furthermore, genotype-dependent differences in ATM expression were demonstrated both in cell lines (p < 0.001) and in individual lung tissue samples (p = 0.003), which supported the results of the association study. Conclusions: Genetic polymorphisms of ATM are significantly associated with RP risk. These variants might exert their effect through regulation of ATM expression and serve as independent biomarkers for prediction of RP in patients treated with thoracic radiotherapy.

Zhang Li [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Yang Ming [Department of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Bi Nan [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Fang Mingjing; Sun Tong [Department of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Ji Wei [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Tan Wen [Department of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Zhao Lujun [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Yu Dianke [Department of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Lin Dongxin, E-mail: dlin@public.bta.net.c [Department of Etiology and Carcinogenesis, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China); Wang Luhua, E-mail: wlhwq@yahoo.co [Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing (China)

2010-08-01T23:59:59.000Z

108

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

109

Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells  

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

Low Dose Radiation Research Program: Low Dose Response of Respiratory Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells in Intact Tissues and Reconstituted Tissue Constructs Authors: John Ford, Amy Maslowski, Alex Redd and Les Braby Institutions: Texas A&M University, College Station, TX We are developing a model of respiratory tissue using a perfusion culture system. We are using this system to quantify the effects of normal tissue architecture, and the interaction of epithelial cells with other cell types, on radiation-induced bystander effects. Tracheal tissue taken from young adult Fischer 344 rats is imbedded in a growth factor enriched agarose matrix. The chamber is designed to allow growth medium to periodically wash the epithelial surface of the tracheal lumen while maintaining the air-interface that is necessary for the normal

110

Global methylation responses to low dose radiation exposure  

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

methylation responses to low dose radiation exposure methylation responses to low dose radiation exposure Pamela J Sykes, Michelle R Newman, Benjamin J Blyth and Rebecca J Ormsby Haematology and Genetic Pathology, Flinders University and Medical Centre, Flinders Centre for Cancer Prevention and Control, Bedford Park, Adelaide, South Australia 5042 Australia. (pam.sykes@flinders.edu.au). Our goal is to study the mechanisms involved in biological responses to low doses of radiation in vivo in the dose range that is relevant to population and occupational exposures. At high radiation doses, DNA double-strand breaks are considered the critical lesion underlying the initiation of radiation-induced carcinogenesis. However, at the very low radiation doses relevant for the general public, the induction of DNA double-strand breaks

111

Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation-Induced Senescence of Human Mesenchymal Stem Cells  

SciTech Connect

Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastoma (Rb) protein, p53, p21{sup waf1/Cip1}, and p16{sup INK4A}), and senescence-associated secretory phenotypes (SASPs) (IL-8, IL-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole (TBB) and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT)), and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2{alpha} and CK2{alpha}{prime} induced hMSC senescence. However, only knockdown of CK2{alpha} resulted in morphological phenotypes resembling those of radiation-induced senescence. These results suggest that CK2{alpha} and CK2{alpha}{prime} play differential roles in hMSC senescence progression, and their relative expression might represent a novel regulatory mechanism for CK2 activity.

Wang, Daojing; Jang, Deok-Jin

2009-08-21T23:59:59.000Z

112

Low Dose Radiation Research Program: Research Highlights - Collateral  

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

Collateral Damage Collateral Damage Using targeted irradiation to understand radiation-induced effects in bystander cells chromosomal A typical example of chromosomal instability induction measured by chromosome-type aberrations in primary human lymphocytes at delay time post-irradiation of a fraction of the cell population. Similar types of aberrations were observed in whole irradiated population but were not observed in untreated cells. Munira Kadhim Background: It has long been understood that radiation exposure can influence cellular changes. Studies indicate that even very low doses of high linear energy transfer (LET) alpha-particle irradiation, such as that from environmental radon, can affect cells. Radiation-induced genomic instability can be observed in the progeny of irradiated cells and as a

113

Low Dose Radiation Research Program: Induction of Genomic Instability...  

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

Brook Why This Project Genomic instability is an important step in radiation-induced cancer. We will investigate one potential repair mechanism involved in radiation-induced...

114

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

115

Apoptosis as a Mechanism for Low Dose Radiation-and Amifostine-Mediated  

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

Apoptosis as a Mechanism for Low Dose Radiation- and Amifostine-Mediated Apoptosis as a Mechanism for Low Dose Radiation- and Amifostine-Mediated Chromosomal Inversion Responses Pam Sykes Flinders University and Medical Centre Abstract Low dose radiation and the chemical radioprotector amifostine have both been shown to protect cells from the immediate and delayed effects of radiation exposure. They display a number of distinct similarities including their ability to protect cells against radiation-induced DNA damage, radiation-induced cell death and metastases formation. Amifostine, which protects cells from the toxic effects of ionizing radiation, has a broad range of activities including free radical scavenging, polyamine-like DNA binding, and induction of hypoxia and redox-regulated genes. Amifostine’s ability to protect cells is often

116

Radioadaptation in Neural Stem Cells Exposed to Low Dose Irradiation  

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Radioadaptation in Neural Stem Cells Exposed to Low Dose Irradiation Radioadaptation in Neural Stem Cells Exposed to Low Dose Irradiation Charles Limoli University of California, Irvine Abstract In the CNS, irradiation of multipotent neural stem and precursor cells has been shown to cause a persistent oxidative stress that impacts radiosensitivity, mitochondrial function, and cell fate. The nature, magnitude and duration of reactive species dictates whether these radiation-induced changes are harmful or beneficial to a variety of in vitro and in vivo endpoints of viability and function. We have shown that acute low dose irradiation (2-10 cGy) can elicit significant increases in reactive oxygen (ROS) and nitrogen (RNS) species over several days post-exposure. These changes can be attenuated when the dose is protracted over several weeks using a 57Co flood source having a surface dose rate of

117

Radiation Leukemogenesis at Low Dose Rates  

SciTech Connect

The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an ?inverse dose rate effect? for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

Weil, Michael; Ullrich, Robert

2013-09-25T23:59:59.000Z

118

Radiation-induced leukemia: Comparative studies in mouse and man. Annual performance report, June 1, 1991--October 31, 1991  

SciTech Connect

We now have a clear understanding of the mechanism by which radiation-induced (T-cell) leukemia occurs. In irradiated mice (radiation-induced thymic leukemia) and in man (acute lymphoblastic T-cell leukemia, T-ALL) the mechanism of leukemogenesis is surprisingly similar. Expressed in the most elementary terms, T-cell leukemia occurs when T-cell differentiation is inhibited by a mutation, and pre-T cells attempt but fail to differentiate in the thymus. Instead of leaving the thymus for the periphery as functional T-cells they continue to proliferate in the thymus. The proliferating pre- (pro-) T-cells constitute the (early) acute T-cell leukemia (A-TCL). This model for the mechanism of T-cell leukemogenesis accounts for all the properties of both murine and human A-TCL. Important support for the model has recently come from work by Ilan Kirsch and others, who have shown that mutations/deletions in the genes SCL (TAL), SIL, and LCK constitute primary events in the development of T-ALL, by inhibiting differentiation of thymic pre- (pro-) T-cells. This mechanism of T-cell leukemogenesis brings several specific questions into focus: How do early A-TCL cells progress to become potently tumorigenic and poorly treatable? Is it feasible to genetically suppress early and/or progressed A-TCL cells? What is the mechanism by which the differentiation-inhibited (leukemic) pre-T cells proliferate? During the first grant year we have worked on aspects of all three questions.

Haas, M.

1991-12-31T23:59:59.000Z

119

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

120

DOE contractors' workshop: Cellular and molecular aspects of radiation induced DNA damage and repair  

SciTech Connect

For four decades the US Department of Energy and its predecessors have been the lead federal agency in supporting radiation biology research. Over the years emphasis in this program has gradually shifted from dose-effect studies on animals to research on the effects of radiations of various qualities on cells and molecules. Mechanistic studies on the action of radiation at the subcellular level are few in number and there is a need for more research in this area if we are to gain a better understanding of how radiation affects living cells. The intent of this workshop was to bring together DOE contractors and grantees who are investigating the effects of radiation at the cellular and molecular levels. The aims were to foster the exchange of information on research projects and experimental results, promote collaborative research efforts, and obtain an overview of research currently supported by the Health Effects Research Division of the Office of Health and Environmental Research. The latter is needed by the Office for program planning purposes. This report on the workshop which took place in Albuquerque, New Mexico on March 10-11, 1987, includes an overview with future research recommendations, extended abstracts of the plenary presentations, shorter abstracts of each poster presentation, a workshop agenda and the names and addresses of the attendees.

Not Available

1987-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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.


121

Information bias and lifetime mortality risks of radiation-induced cancer: Low LET radiation  

Science Conference Proceedings (OSTI)

Additive and multiplicative models of relative risk were used to measure the effect of cancer misclassification and DS86 random errors on lifetime risk projections in the Life Span Study (LSS) of Hiroshima and Nagasaki atomic bomb survivors. The true number of cancer deaths in each stratum of the cancer mortality cross-classification was estimated using sufficient statistics from the EM algorithm. Average survivor doses in the strata were corrected for DS86 random error ({sigma}=0.45) by use of reduction factors. Poisson regression was used to model the corrected and uncorrected mortality rates with risks in RERF Report 11 (Part 2) and the BEIR-V Report. Bias due to DS86 random error typically ranged from {minus}15% to {minus}30% for both sexes, and all sites and models. The total bias, including diagnostic misclassification, of excess risk of nonleukemia for exposure to 1 Sv from age 18 to 65 under the non-constant relative project model was {minus}37.1% for males and {minus}23.3% for females. Total excess risks of leukemia under the relative projection model were biased {minus}27.1% for males and {minus}43.4% for females. Thus, nonleukemia risks for 1 Sv from ages 18 to 65 (DRREF=2) increased from 1.91%/Sv to 2.68%/Sv among males and from 3.23%/Sv to 4.92%/Sv among females. Leukemia excess risk increased from 0.87%/Sv to 1.10/Sv among males and from 0.73%/Sv to 1.04/Sv among females. Bias was dependent on the gender, site, correction method, exposure profile and projection model considered. Future studies that use LSS data for US nuclear workers may be downwardly biased if lifetime risk projections are not adjusted for random and systematic errors.

Peterson, L.E.; Schull, W.J.; Davis, B.R. [Texas Univ., Houston, TX (United States). Health Science Center; Buffler, P.A. [California Univ., Berkeley, CA (United States). School of Public Health

1994-04-01T23:59:59.000Z

122

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

Science Conference Proceedings (OSTI)

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

123

Does oxygen enhance the radiation-induced inactivation of penicillinase. Progress report, December 1, 1979-November 30, 1980  

DOE Green Energy (OSTI)

The radiation-induced inactivation of penicillinase in dilute aqueous solutions buffered with phosphate was studied, by examining enzyme radiosensitivity in the presence of various gases (He, O/sub 2/, H/sub 2/, N/sub 2/O, N/sub 2/O + O/sub 2/). The introduction of either N/sub 2/O or O/sub 2/ was found to reduce the radiodamage. On the other hand H/sub 2/ or N/sub 2/O + O/sub 2/ gas-mixture enhanced the radiosensitivity. In the presence of formate and oxygen, no enzyme inactivation was detected. The results indicated that the specific damaging efficiency of H atoms is almost four-fold higher than that of OH radical; therefore in phosphate buffer, where more than half of the free radicals are H atoms, it is the H radicals that are responsible for the majority of the damage. The superoxide radicals appeared to be completely inactive and did not contribute toward enzyme inactivation. Oxygen was shown to affect the radiosensitivity in two ways. On one side, it protected by converting e/sup -//sub aq/ and H radicals into harmless O/sub 2//sup -/ radicals. On the other side it increased the inactivation by enhancing the damage brought about by OH radicals (OER = 2.8). In the present case the oxygen effect of protection exceeded that of sensitization, thus giving rise to a moderate overall protection effect.

Samuni, A.; Kalkstein, A.; Czapski, G.

1980-01-01T23:59:59.000Z

124

Microsoft PowerPoint - Powerpoint_Adaptive.ppt [Compatibility Mode]  

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

Response Response to Low Dose Radiation Adaptive Response Adaptive Response When large radiation When large radiation exposure is preceded by a ll " i kl " d h small "tickle" dose, the effect of the large dose is effect of the large dose is sometimes diminished The first time you go to the beach in the summer you don't usually spend 8 hours in summer, you don t usually spend 8 hours in the sun. You begin by being out an hour or d dd ddi i l i h i ki two and add additional time as their skin adapts to the sunny condition and develops protective mechanisms.... Adaptive Response Adaptive Response In some cases, cells also show an "adaptive response" to radiation, although researchers p , g are still trying to understand how the protective mechanisms work. Small doses p

125

Low Dose Radiation Research Program: Molecular Characterization of the  

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

Molecular Characterization of the Roles of SOD Genes in Mammalian Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li, Zhanjun Guo, Zhonghui Yang, and Eric Chuang Institutions: Dept of Radiation Oncology, Duke University Medical Center, Durham, NC Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland Background The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

126

Low Dose Radiation Research Program: 2003 Molecular Characterization of the  

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

Characterization of the Roles of SOD Genes in Mammalian Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li,1 Eric Chuang2 Institutions: 1Dept of Radiation Oncology, Duke University Medical Center, Durham, NC, 2Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore, internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

127

Low Dose Radiation Research Program: Genetic Factors Affecting  

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

Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Radiation. Authors: William F. Morgan, Pat Concannon & John H.J. Petrini The goal of this program is to test the hypothesis that mice heterozygous for the NBS1 gene are genetically susceptible to low doses of ionizing radiation. Patients with Nijmegen Breakage Syndrome (NBS) are radiation sensitive, because of defects in cellular responses to radiation induced genetic damage. It is unclear whether humans heterozygous for the mutations associated with NBS are radiation sensitive and results from cell culture experiments give conflicting results. In collaboration with John Petrini at the Memorial Sloan Kettering Cancer Center in New York City we developed a mouse model of this disorder and are directly testing the hypothesis

128

Mechanisms underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation  

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

underlying cellular responses of cells from haemopoeitic underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation Munira Kadhim 1 , Sarah Irons 1 , Deborah Bowler 1 , Virginia Serra 1 , Stefania Militi 2 , Kim Chapman 1 1 Genomic Instability Research Group, School of Life Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford, Oxfordshire, OX3 0BP, UK 2 Mammalian Genetics Unit, Medical Research Council Harwell, Harwell Science and Innovation Campus, Oxfordshire, OX11 0RD, UK Radiation-induced responses at the cellular and whole body levels are influenced by genetic predisposition, with implications for environmental and potentially, diagnostic exposures. Currently, the extent to which genetic background play a role in the mechanisms and signalling pathways involved in radiation-induced

129

Adaptive sampler  

DOE Patents (OSTI)

An adaptive data compression device for compressing data having variable frequency content, including a plurality of digital filters for analyzing the content of the data over a plurality of frequency regions, a memory, and a control logic circuit for generating a variable rate memory clock corresponding to the analyzed frequency content of the data in the frequency region and for clocking the data into the memory in response to the variable rate memory clock.

Watson, Bobby L. (Idaho Falls, ID); Aeby, Ian (Fremont, CA)

1982-01-01T23:59:59.000Z

130

Adaptive sampler  

DOE Patents (OSTI)

An adaptive data compression device for compressing data is described. The device has a frequency content, including a plurality of digital filters for analyzing the content of the data over a plurality of frequency regions, a memory, and a control logic circuit for generating a variable rate memory clock corresponding to the analyzed frequency content of the data in the frequency region and for clocking the data into the memory in response to the variable rate memory clock.

Watson, B.L.; Aeby, I.

1980-08-26T23:59:59.000Z

131

Low Dose Radiation Research Program: Janet E. Baulch  

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

Janet E. Baulch Janet E. Baulch University of California, Davis Currently Funded Projects Impact of Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation Technical Abstracts 2003 Workshop: DNA damage in acutely irradiated F2 mice with a history of paternal F0 germline irradiation Baulch, J.E. and Raabe, O G. 2002 Workshop Impact of Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation, Baulch, J.E., Ph.D. and Raabe, O.G., Ph.D. Publications Kovalchuk, O. and Baulch, J.E. (2008). Epigenetic changes and nontargeted radiation effects - Is there a link? Environmental and Molecular Mutagenesis 49(1):16-25 Laiakis, E.C., Baulch, J.E., and Morgan, W.F. (2008). Interleukin 8 exhibits a pro-mitogenic and pro-survival role in radiation induced

132

Low Dose Radiation Research Program: Molecular Characterization of Survival  

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

Survival Advantage, Bystander Effect, and Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Mohan Natarajan University of Texas Health Science Center Why this Project? To understand the molecular link between the activation of NF-kB and cellular outcomes such as better cell survival after low-LET radiation and to determine whether low dose radiation-induced NF-kB signaling can mediate telomerase activation and thus confer enhanced cell survival of normal aortic endothelial cells. Project Goals To determine whether low-linear energy transfer (LET) radiation can cause a positive feedback signal initiated by the activation of the NF-kB. To examine one of the mechanisms involving TNF-a as a signaling mediator, which could mediate the bystander effect through the generation

133

The Effects of Low Dose Irradiation on Inflammatory Response Proteins in a 3D Reconstituted Human Skin Tissue Model  

Science Conference Proceedings (OSTI)

Skin responses to moderate and high doses of ionizing radiation include the induction of DNA repair, apoptosis, and stress response pathways. Additionally, numerous studies indicate that radiation exposure leads to inflammatory responses in skin cells and tissue. However, the inflammatory response of skin tissue to low dose radiation (<10 cGy) is poorly understood. In order to address this, we have utilized a reconstituted human skin tissue model (MatTek EpiDerm FT) and assessed changes in 23 cytokines twenty-four and forty eight hours following treatment of skin with either 3 or 10 cGy low-dose of radiation. Three cytokines, IFN-?, IL-2, MIP-1?, were significantly altered in response to low dose radiation. In contrast, seven cytokines were significantly altered in response to a high radiation dose of 200 cGy (IL-2, IL-10, IL-13, IFN-?, MIP-1?, TNF ?, and VEGF) or the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (G-CSF, GM-CSF, IL-1?, IL-8, MIP-1?, MIP-1?, RANTES). Additionally, radiation induced inflammation appears to have a distinct cytokine response relative to the non-radiation induced stressor, TPA. Overall, these results indicate that there are subtle changes in the inflammatory protein levels following exposure to low dose radiation and this response is a sub-set of what is seen following a high dose in a human skin tissue model.

Varnum, Susan M.; Springer, David L.; Chaffee, Mary E.; Lien, Katie A.; Webb-Robertson, Bobbie-Jo M.; Waters, Katrina M.; Sacksteder, Colette A.

2012-12-01T23:59:59.000Z

134

Radiation-induced changes in glomerular and tubular cell kinetics and morphology following irradiation of a single kidney in the pig  

Science Conference Proceedings (OSTI)

Radiation-induced changes in glomerular and tubular cell kinetics and morphology following irradiation of a single pig kidney were assessed. Irradiation of the right kidney alone resulted in a significant increase in renal cell labeling index (LI) in both the irradiated and the contralateral unirradiated kidney within 2 weeks of irradiation; peak values of 1.57 {plus_minus} 0.32% and 1.04 {plus_minus} 0.13%, respectively, were seen 4 weeks PI, significantly greater (p tab.

Robbins, M.E.C.; Bonsib, S.M.; Ikeda, A. [Univ. of Iowa, Iowa City, IA (United States)] [and others

1995-07-15T23:59:59.000Z

135

Study Shows Roles of Receptor, Thiol on Adaptive Response  

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

Study Shows Roles of Receptor, Thiol on Adaptive Response Study Shows Roles of Receptor, Thiol on Adaptive Response Jeffrey Murley Jeffrey Murley, Ph.D. David Grdina, Ph.D. Low Dose program-supported scientists at The University of Chicago have gained more insight into adaptive protective responses indicating the role of oxidative stress, the role of reactive oxygen species (ROS), and the induction of SOD2 (manganese Superoxide Dismutase) activity. These changes are central to the production of adaptive protective responses. Why Study Adaptive Response? Exposing cells to low doses of ionizing radiation has been reported to elevate resistance to genomic damage when the same cells are subsequently exposed to a much higher dose of radiation. This phenomenon, called adaptive response, is characterized by an increase

136

Internal Dose Estimates from  

E-Print Network (OSTI)

Appendix F Internal Dose Estimates from NTS Fallout F-1 #12;Radiation Dose to the Population...........................................................................................40 Comparison to dose estimates from global fallout

137

Isotoxic Dose Escalation in the Treatment of Lung Cancer by Means of Heterogeneous Dose Distributions in the Presence of Respiratory Motion  

Science Conference Proceedings (OSTI)

Purpose: To test, in the presence of intrafractional respiration movement, a margin recipe valid for a homogeneous and conformal dose distribution and to test whether the use of smaller margins combined with heterogeneous dose distributions allows an isotoxic dose escalation when respiratory motion is considered. Methods and Materials: Twenty-three Stage II-III non-small-cell lung cancer patients underwent four-dimensional computed tomography scanning. The gross tumor volume and clinical target volume (CTV) were outlined in the mid-ventilation phase. The CTV-to-planning target volume (PTV) margin was calculated by use of a standard margin recipe and the patient-specific respiration pattern. Standard three-dimensional treatment plans were generated and recalculated on the remaining respiration phases. The planning was repeated for a CTV-to-PTV margin decreased by 2.5 and 5 mm relative to the initial margin in all directions. Time-averaged dose-volume histograms (four-dimensional dose-volume histograms) were calculated to evaluate the CTV-to-PTV margin. Finally, the dose was escalated in the plans with decreased PTV such that the mean lung dose (predictor of radiation-induced pneumonitis) was equal to mean lung dose in the plan by use of the initially calculated margin. Results: A reduction of the standard margin by 2.5 mm compared with the recipe resulted in too low of a minimum dose for some patients. A combination of dose escalation and use of heterogeneous dose distribution was able to increase the minimum dose to the target by approximately 10% and 20% for a CTV-to-PTV margin reduction of 2.5 mm and 5.0 mm, respectively. Conclusion: The margin recipe is valid for intrafractional respiration-induced tumor motions. It is possible to increase the dose to the target without increased mean lung dose with an inhomogeneous dose distribution.

Baker, Mariwan; Nielsen, Morten [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Hansen, Olfred [Department of Oncology, Odense University Hospital, Odense (Denmark); Jahn, Jonas Westberg [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Korreman, Stine [Department of Radiation Oncology, Copenhagen University Hospital, Copenhagen (Denmark); Brink, Carsten, E-mail: carsten.brink@ouh.regionsyddanmark.dk [Laboratory of Radiation Physics, Odense University Hospital, Odense (Denmark); Institute of Clinical Research, University of Southern Denmark, Odense (Denmark)

2011-11-01T23:59:59.000Z

138

Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures  

SciTech Connect

OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase ones risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based on applications of NEOTRANS2, indicate that nonlinear threshold-type, dose-response relationships for excess stochastic effects (problematic nonlethal mutations, neoplastic transformation) should be expected after exposure to low linear energy transfer (LET) gamma rays or gamma rays in combination with high-LET alpha radiation. Similar thresholds are expected for low-dose-rate low-LET beta irradiation. We attribute the thresholds to low-dose, low-LET radiation induced protection against spontaneous mutations and neoplastic transformations. The protection is presumed mainly to involve selective elimination of problematic cells via apoptosis. Low-dose, low-LET radiation is presumed to trigger wide-area cell signaling, which in turn leads to problematic bystander cells (e.g., mutants, neoplastically transformed cells) selectively undergoing apoptosis. Thus, this protective bystander effect leads to selective elimination of problematic cells (a tissue cleansing process in vivo). However, this protective bystander effects is a different process from low-dose stimulation of the immune system. Low-dose, low-LET radiation stimulation of the immune system may explain why thresholds for inducing excess cancer appear much larger (possibly more than 100-fold larger) than thresholds for inducing excess mutations and neoplastic transformations, when the dose rate is low. For ionizing radiation, the current risk assessment paradigm is such that the relative risk (RR) is always 1, no matter how small the dose. Our research results indicate that for low-dose or low-dose-rate, low-LET irradiation, RR < 1 may be more the rule than the exception. Directly tied to the current RR paradigm are the billion-dollar cleanup costs for radionuclide-contaminated DOE sites. Our research results suggest that continued use of the current RR paradigm for which RR 1 could cause more harm than benefit to society (e.g., by spreading unwarranted fear about phantom excess risks associated with low-dose low-LET radiation). Such phantom risks also may arise from risk assessments conducted for com

Scott, Bobby, R., Ph.D.

2003-06-27T23:59:59.000Z

139

Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures  

Science Conference Proceedings (OSTI)

OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase ones risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based on applications of NEOTRANS2, indicate that nonlinear threshold-type, dose-response relationships for excess stochastic effects (problematic nonlethal mutations, neoplastic transformation) should be expected after exposure to low linear energy transfer (LET) gamma rays or gamma rays in combination with high-LET alpha radiation. Similar thresholds are expected for low-dose-rate low-LET beta irradiation. We attribute the thresholds to low-dose, low-LET radiation induced protection against spontaneous mutations and neoplastic transformations. The protection is presumed mainly to involve selective elimination of problematic cells via apoptosis. Low-dose, low-LET radiation is presumed to trigger wide-area cell signaling, which in turn leads to problematic bystander cells (e.g., mutants, neoplastically transformed cells) selectively undergoing apoptosis. Thus, this protective bystander effect leads to selective elimination of problematic cells (a tissue cleansing process in vivo). However, this protective bystander effects is a different process from low-dose stimulation of the immune system. Low-dose, low-LET radiation stimulation of the immune system may explain why thresholds for inducing excess cancer appear much larger (possibly more than 100-fold larger) than thresholds for inducing excess mutations and neoplastic transformations, when the dose rate is low. For ionizing radiation, the current risk assessment paradigm is such that the relative risk (RR) is always 1, no matter how small the dose. Our research results indicate that for low-dose or low-dose-rate, low-LET irradiation, RR fear about phantom excess risks associated with low-dose low-LET radiation). Such phantom risks also may arise from risk assessments conducted for com

Scott, Bobby, R., Ph.D.

2003-06-27T23:59:59.000Z

140

Low Dose Radiation Research Program: Cooperation Between Homologous  

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

Cooperation Between Homologous Recombination and the Fanconi Anemia Cooperation Between Homologous Recombination and the Fanconi Anemia Cancer Suppressor Proteins in Minimizing Spontaneous and Radiation-Induced Chromosomal Instability Authors: Larry H. Thompson, John M. Hinz, Robert S. Tebbs, and N. Alice Yamada Institutions: Biosciences Directorate, Lawrence Livermore National Laboratory, Livermore, California Purpose and experimental approach. This study addresses the genetic basis of spontaneous mutagenesis as a means of understanding the DNA damage-response pathways that maintain chromosome stability. It is our view that knowledge of these processes is fundamental to understanding how low dose ionizing radiation (IR) produces chromosomal rearrangements that lead to carcinogenesis. Endogenous oxidative DNA damage is presumed to be a

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141

Low Dose Radiation Research Program: Robert L. Ullrich  

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

Robert L. Ullrich Robert L. Ullrich Colorado State University Currently Funded Projects Radiation Leukemogenesis at Low Dose Rates (NSCOR) Genetic Mechanisms of Induced Chromosomal Instability and their Relationships with Radiation Tumorigenesis Technical Abstracts 2006 Workshop: The Role of Telomere Dysfunction in Driving Genomic Instability Bailey, S.M., Williams, E.S., and Ullrich, R.L. 2005 Workshop: Dsyfunctional Mammalian Telomeres in DNA-PKcs Deficient Backgrounds Bailey, S.M., Williams, E., Hagelstrom, T., and Ullrich, R.L. 2003 Workshop: Dysfunctional Mammalian Telomeres Join to Double-Strand Breaks Bailey, S.M., Goodwin, E.H., Williams, E., and Ullrich, R.L. 2002 Workshop: Dysfunctional Telomeres, Radiation-Induced Instability and Tumorigenesis Bailey, S.M., Goodwin, E.H., Cornforth, M.N., and Ullrich, R.L.

142

Low Dose Radiation Research Program: Use of Computational Modeling to  

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

Use of Computational Modeling to Evaluate Hypotheses about the Use of Computational Modeling to Evaluate Hypotheses about the Molecular and Cellular Mechanisms of Bystander Effects Authors: Yuchao “Maggie” Zhao and Rory Conolly Institutions: CIIT Centers for Health Research, 6 Davis Drive, Research Triangle Park, North Carolina A detailed understanding of the biological mechanisms of radiation-induced damage at the molecular and cellular levels is needed for accurate assessment of the shape of the dose-response curve for radiationinduced health effects in the intact organism. Computational models can contribute to the improved understanding of mechanisms through integration of data and quantitative evaluation of hypotheses. We propose to develop a novel computational model of bystander effects elicited by oxidative stress and a

143

Low Dose Radiation Research Program: Rainer K. Sachs  

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

Rainer K. Sachs Rainer K. Sachs University of California, Berkeley Funded Projects BIO-BASED RISK MODELING 03-20: Modeling the Interrelations Among Radiation-Induced Bystander Effects, Genomic Instability and Cancer Cytogenetic Tests of Radiobiological Models Relating Epidemiologically Measurable Risks to Low-Dose Risks Technical Abstracts 2006 Workshop The Bystander Effect in Normal Human 3-D Tissue: Experiments, Models, and Implications Brenner, D., Ponnaiya, B., Shuryak, I., Sachs, R., and Geard, D. Radiation Carcinogenesis Risk as Influenced by Intercellular Interaction Hahnfeldt, P., Hlatky, L., and Sachs, R.K. 2005 Workshop: Modelling Intercellular Interactions During Radiation Carcinogenesis Sachs, R.K., Chan, M., Hlatky, L., and Hahnfeldt, P. 2003 Workshop: Chromosome Spatial Clustering Uncovered Through Radiogenic Aberrations

144

Suppression of Tumorigenesis by Adaptive Response in Mice  

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

of the adaptive response in mind, we have investigated the effects of low-dose-rate irradiation on the process of tumorigenesis at a whole body level in mice. Thymic lymphomas...

145

Low Dose Radiation Research Program: James D. Tucker  

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

Role of the Adaptive Response in determining health risks from in vivo exposures to low dose of ionizing radiation Tucker, J. Publications Christian, A.T., Patte, M.S., Attix,...

146

Monte-Carlo Simulations of Radiation-Induced Activation in a Fast-Neutron and Gamma- Based Cargo Inspection System  

E-Print Network (OSTI)

An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron and gamma radiation inside the cargo, as well as the dose delivered by these isotopes to people in contact with the cargo during and following the interrogation procedure. Using MCNPX and CINDER90 we have calculated the activation levels for several typical inspection scenarios. One example is the activation of various metal samples embedded in a cotton-filled container. To validate the simulation results, a benchmark experiment was performed, in which metal samples were activated by fast-neutrons in a water-filled glass jar. The induced activity was determined by analyzing the gamma spectra. Based on the calculated radioactive inventory in the container, the dose levels due to the induced gamma radiation were calculated at several distances from the container and in relevant time windows after the irradiation, in order to evaluate the radiation exposure of the cargo handling staff, air crew and passengers during flight. The possibility of remanent long-lived radioactive inventory after cargo is delivered to the client is also of concern and was evaluated.

B. Bromberger; D. Bar; M. Brandis; V. Dangendorf; M. B. Goldberg; F. Kaufmann; I. Mor; R. Nolte; M. Schmiedel; K. Tittelmeier; D. Vartsky; H. Wershofen

2012-01-04T23:59:59.000Z

147

Radiation-induced instability of MnS precipitates and its possible consequences on irradiation-induced stress corrosion cracking of austenitic stainless steels  

SciTech Connect

Irradiation-assisted stress corrosion cracking (IASCC) is a significant materials issue for the light water reactor (LWR) industry and may also pose a problem for fusion power reactors that will use water as coolant. A new metallurgical process is proposed that involves the radiation-induced release into solution of minor impurity elements not usually thought to participate in IASCC. MnS-type precipitates, which contain most of the sulfur in stainless steels, are thought to be unstable under irradiation. First, Mn transmutes strongly to Fe in thermalized neutron spectra. Second, cascade-induced disordering and the inverse Kirkendall effect operating at the incoherent interfaces of MnS precipitates are thought to act as a pump to export Mn from the precipitate into the alloy matrix. Both of these processes will most likely allow sulfur, which is known to exert a deleterious influence on intergranular cracking, to re-enter the matrix. To test this hypothesis, compositions of MnS-type precipitates contained in several unirradiated and irradiated heats of Type 304, 316, and 348 stainless steels (SSs) were analyzed by Auger electron spectroscopy. Evidence is presented that shows a progressive compositional modification of MnS precipitates as exposure to neutrons increases in boiling water reactors. As the fluence increases, the Mn level in MnS decreases, whereas the Fe level increases. The S level also decreases relative to the combined level of Mn and Fe. MnS precipitates were also found to be a reservoir of other deleterious impurities such as F and O which could be also released due to radiation-induced instability of the precipitates.

Chung, H.M.; Sanecki, J.E. [Argonne National Lab., IL (United States); Garner, F.A. [Pacific Northwest National Lab., Richland, WA (United States)

1996-12-01T23:59:59.000Z

148

Induction of DNA Damage by Low Dose PET scans  

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

Induction of DNA Damage by Low Dose PET scans Induction of DNA Damage by Low Dose PET scans Douglas Boreham McMaster University Abstract This research is focused on assessing the radiation risk associated with positron emission tomography (PET) scans. It has been suggested that low dose medical imaging, such as PET scans, carry an added biological risk because they expose the patient to ionizing radiation. PET scanning is an increasingly used nuclear medicine procedure that requires the administration of isotope 18F-fluorodeoxyglucose (18F-FDG, E=250 keV β and 511 keV γ) and results in an effective dose to the patient ranging from 7-22 mSv. The radiation induced DNA damage associated with a PET scan was studied in 7-9 week old female wild type Trp53 +/+ mice. Mice were given a PET scan with 18F-FDG and the biological response was assessed in bone marrow using

149

Low Dose Radiation Research Program: Mary Helen Barcellos-Hoff - 2003  

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DOE Low Dose Radiation Program Workshop IV DOE Low Dose Radiation Program Workshop IV Abstract Title: TGF-β Protects Human Mammary Epithelial Cells from Radiation-Induced Centrosome Amplification Authors: Mary Helen Barcellos-Hoff, Bahram Parvin, Anna C. Erickson and Rishi Gupta Institutions: Department of Cell and Molecular Biology, Life Sciences Division, Ernest Orlando Lawrence, Berkeley National Laboratory, Berkeley, California In recent studies we have shown that ionizing radiation (IR), a known carcinogen of human and murine mammary gland, compromises human mammary epithelial cell (HMEC) polarity and multicellular organization in a manner characteristic of neoplastic progression through a heritable, non-mutational mechanism (1). Thus, when all cells are irradiated with a significant dose (2 Gy), the daughters of irradiated cells lose their

150

In Vivo Effects of Low Dose γ-Rays on Mitochondrial Function  

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In Vivo Effects of Low Dose γ-Rays on Mitochondrial Function In Vivo Effects of Low Dose γ-Rays on Mitochondrial Function Edouard Azzam New Jersey Medical School Cancer Center Abstract Mitochondria consume about 90% of the body’s oxygen and are the richest source of reactive oxygen species (ROS). They play an integral part in signaling events that occur in response to oxidizing agents, including ionizing radiation. To gain insight into radiation-induced effects on mitochondria, we investigated the in vivo effects of low dose γ-rays on mitochondrial protein import, aconitase activity and modulation of antioxidants in tissues of whole body-irradiated mice. Mitochondrial protein import is a fundamental mechanism of mitochondrial biogenesis, and the TCA cycle in the mitochondrial matrix is a central pathway of oxidative

151

Low Dose Radiation Research Program: A Variable Energy Soft X-ray  

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

Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect Melvyn Folkard Gray Cancer Institute Why This Project The aim of this project is to determine the effects of low radiation doses using a machine that makes it possible to radiate one cell at a time. Our soft X-ray microprobe can irradiate individual cells, or locations within cells with defined doses and with sub-micron precision. We can use low doses approaching that of a single electron track, which is of relevance to environmental level exposures. Much of our work is concentrating on irradiating specified individual cells within cell populations to identify "bystander responses" where non-radiated cells respond to signals from nearby radiated cells. Higher energy x-rays are being generated to extend

152

Cyclin D1 and CDK4 translocate into mitochondria and interact...  

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

with MnSOD in low dose radiation- induced adaptive radioprotection Cuihong Jin 1 , Ming Fan 1 , Rui Liu 1 , Danupon Nantajit 1 , Demet Candas 1 , Andrew T.M. Vaughan 1 , Jeffrey...

153

Monte-Carlo Simulations of Radiation-Induced Activation in a Fast-Neutron and Gamma- Based Cargo Inspection System  

E-Print Network (OSTI)

An air cargo inspection system combining two nuclear reaction based techniques, namely Fast-Neutron Resonance Radiography and Dual-Discrete-Energy Gamma Radiography is currently being developed. This system is expected to allow detection of standard and improvised explosives as well as special nuclear materials. An important aspect for the applicability of nuclear techniques in an airport inspection facility is the inventory and lifetimes of radioactive isotopes produced by the neutron and gamma radiation inside the cargo, as well as the dose delivered by these isotopes to people in contact with the cargo during and following the interrogation procedure. Using MCNPX and CINDER90 we have calculated the activation levels for several typical inspection scenarios. One example is the activation of various metal samples embedded in a cotton-filled container. To validate the simulation results, a benchmark experiment was performed, in which metal samples were activated by fast-neutrons in a water-filled glass jar. T...

Bromberger, B; Brandis, M; Dangendorf, V; Goldberg, M B; Kaufmann, F; Mor, I; Nolte, R; Schmiedel, M; Tittelmeier, K; Vartsky, D; Wershofen, H

2012-01-01T23:59:59.000Z

154

Thyroid V30 Predicts Radiation-Induced Hypothyroidism in Patients Treated With Sequential Chemo-Radiotherapy for Hodgkin's Lymphoma  

Science Conference Proceedings (OSTI)

Purpose: Hypothyroidism (HT) is a frequent late side effect of Hodgkin's lymphoma (HL) therapy. The purpose of this study is to determine dose-volume constraints that correlate with functional impairment of the thyroid gland in HL patients treated with three-dimensional radiotherapy. Methods and Materials: A total of 61 consecutive patients undergoing antiblastic chemotherapy and involved field radiation treatment (median dose, 32 Gy; range, 30-36 Gy) for HL were retrospectively considered. Their median age was 28 years (range, 14-70 years). Blood levels of thyroid-stimulating hormone (TSH), free triiodo-thyronine (FT3), free thyroxine (FT4), and thyroglobulin antibody (ATG) were recorded basally and at different times after the end of therapy. For the thyroid gland, normal tissue complication probability (NTCP), dosimetric parameters, and the percentage of thyroid volume exceeding 10, 20, and 30 Gy (V10, V20, and V30) were calculated in all patients. To evaluate clinical and dosimetric factors possibly associated with HT, univariate and multivariate logistic regression analyses were performed. Results: Eight of 61 (13.1%) patients had HT before treatment and were excluded from further evaluation. At a median follow-up of 32 months (range, 6-99 months), 41.5% (22/53) of patients developed HT after treatment. Univariate analyses showed that all dosimetric factors were associated with HT (p 62.5%, the risk was 70.8% (p < 0.0001). A Cox regression curve stratified by two levels of V30 value was created (odds ratio, 12.6). Conclusions: The thyroid V30 predicts the risk of developing HT after sequential chemo-radiotherapy and defines a useful constraint to consider for more accurate HL treatment planning.

Cella, Laura [Institute of Biostructures and Bioimages, National Council of Research (CNR), Naples (Italy); Department of Diagnostic Imaging and Radiation Oncology, Federico II University School of Medicine, Naples (Italy); Conson, Manuel; Caterino, Michele; De Rosa, Nicola [Department of Diagnostic Imaging and Radiation Oncology, Federico II University School of Medicine, Naples (Italy); Liuzzi, Raffaele [Institute of Biostructures and Bioimages, National Council of Research (CNR), Naples (Italy); Department of Diagnostic Imaging and Radiation Oncology, Federico II University School of Medicine, Naples (Italy); Picardi, Marco; Grimaldi, Francesco [Department of Biochemistry and Medical Biotechnology, Federico II University School of Medicine, Naples (Italy); Solla, Raffaele [Institute of Biostructures and Bioimages, National Council of Research (CNR), Naples (Italy); Department of Diagnostic Imaging and Radiation Oncology, Federico II University School of Medicine, Naples (Italy); Farella, Antonio; Salvatore, Marco [Department of Diagnostic Imaging and Radiation Oncology, Federico II University School of Medicine, Naples (Italy); Pacelli, Roberto, E-mail: roberto.pacelli@cnr.it [Institute of Biostructures and Bioimages, National Council of Research (CNR), Naples (Italy); Department of Diagnostic Imaging and Radiation Oncology, Federico II University School of Medicine, Naples (Italy)

2012-04-01T23:59:59.000Z

155

Low Dose Radiation Research Program: Melvyn Folkard  

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

Melvyn Folkard Melvyn Folkard Gray Cancer Institute About this Project Currently Funded Projects A Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect Technical Abstracts 2005 Workshop: A Variable-Energy Soft X-Ray Microprobe to Investiage Mechanisms of the Radiation-Induced Bystander Effect Folkard, M., Vojnovic, B., Schettiono, G., Atkinson, K., Prise, K.M., Michael, B.D. 2003 Workshop: A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation -Induced Bystander Effect. Folkard, M., Vojnovic, B., Schettino, G., Atkinson, K., Prise, K.M., Michael, B.D. 2002 Workshop: A Variable-Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect. Folkard, M., Vojnovic, B., Schettino,

156

Low Dose Radiation Research Program: Research Institutions  

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

Institutions Institutions Lovelace Respiratory Research Institute Biological Bases for Radiation Adaptive Responses in the Lung-Lovelace Respiratory Research Institute, Albuquerque, NM USA Contact: Dr. Bobby R. Scott Program Objective Our research focuses on elucidating the biological bases for radiation adaptive responses in the lung and for suppressing lung cancer, and to use the knowledge gained to produce an improved systems-biology-based, risk model for lung cancer induction by low-dose, low linear-energy-transfer (LET) radiation. Research was initiated in October 2009. This research should help foster a new era of low-dose radiation risk/benefit assessment. It will have important implications for possible use of low-dose diagnostic radiation (e.g., X-rays) in cancer therapy. It

157

Experimental Adaptive Bayesian Tomography  

E-Print Network (OSTI)

We report an experimental realization of an adaptive quantum state tomography protocol. Our method takes advantage of a Bayesian approach to statistical inference and is naturally tailored for adaptive strategies. For pure states we observe close to 1/N scaling of infidelity with overall number of registered events, while best non-adaptive protocols allow for $1/\\sqrt{N}$ scaling only. Experiments are performed for polarization qubits, but the approach is readily adapted to any dimension.

Konstantin Kravtsov; Stanislav Straupe; Igor Radchenko; Neil Houlsby; Sergey Kulik

2013-03-07T23:59:59.000Z

158

Low Dose Radiation Research Program: The Adaptive Response in...  

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

Dolling,1 Ron E Mitchel,2 and Douglas R Boreham1 Institutions: 1McMaster University, Canada,2 Atomic Energy of Canada Limited, Canada The Trp53 gene is clearly associated with...

159

Normal Tissue Injury Responses in Mammary Glands After Low Doses...  

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we take advantage of the variation in sensitivity to radiation induced mammary gland cancer in three genetically defined inbred strains of mice (BALBc: sensitive; C57BL6...

160

Low Dose Radiation Research Program: James E. Morris  

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Northwest National Laboratories Past Funded Project Sensitivity to radiation-induced cancer in hemachromatosis. Publications Stevens, R.G., Morris, J.E., and Anderson, L.E....

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161

The Contribution of Tissue Level Organization to Genomic Stability Following Low Dose/Low Dose Rate Gamma and Proton Irradiation  

Science Conference Proceedings (OSTI)

The formation of functional tissue units is necessary in maintaining homeostasis within living systems, with individual cells contributing to these functional units through their three-dimensional organization with integrin and adhesion proteins to form a complex extra-cellular matrix (ECM). This is of particular importance in those tissues susceptible to radiation-induced tumor formation, such as epithelial glands. The assembly of epithelial cells of the thyroid is critical to their normal receipt of, and response to, incoming signals. Traditional tissue culture and live animals present significant challenges to radiation exposure and continuous sampling, however, the production of bioreactor-engineered tissues aims to bridge this gap by improve capabilities in continuous sampling from the same functional tissue, thereby increasing the ability to extrapolate changes induced by radiation to animals and humans in vivo. Our study proposes that the level of tissue organization will affect the induction and persistence of low dose radiation-induced genomic instability. Rat thyroid cells, grown in vitro as 3D tissue analogs in bioreactors and as 2D flask grown cultures were exposed to acute low dose (1, 5, 10 and 200 cGy) gamma rays. To assess immediate (6 hours) and delayed (up to 30 days) responses post-irradiation, various biological endpoints were studied including cytogenetic analyses, apoptosis analysis and cell viability/cytotoxicity analyses. Data assessing caspase 3/7 activity levels show that, this activity varies with time post radiation and that, overall, 3D cultures display more genomic instability (as shown by the lower levels of apoptosis over time) when compared to the 2D cultures. Variation in cell viability levels were only observed at the intermediate and late time points post radiation. Extensive analysis of chromosomal aberrations will give further insight on the whether the level of tissue organization influences genomic instability patterns after low dose radiation exposure. Cells viability/cytotoxicity analysis data are currently being analyzed to determine how these endpoints are affected under our experimental conditions. The results from this study will be translatable to risk assessment for assigning limits to radiation workers, pre-dosing for more effective radiotherapy and the consequences of long duration space flight. The data from this study has been presented a various scientific meetings/workshops and a manuscript, containing the findings, is currently being prepared for publication. Due to unforeseen challenges in collecting the data and standardizing experimental procedures, the second and third aims have not been completed. However, attempts will be made, based on the availability of funds, to continue this project so that these aims can be satisfied.

Cheryl G. Burrell, Ph.D.

2012-05-14T23:59:59.000Z

162

Relationship Between Grain Boundary Structure and Radiation Induced Segregation in a Neutron Irradiated 9 wt. % Cr Model Ferritic/Martensitic Steel  

Science Conference Proceedings (OSTI)

Ferritic/Martensitic (F/M) steels with high Cr content posses the high temperature strength and low swelling rates required for advanced nuclear reactor designs. Radiation induced segregation (RIS) occurs in F/M steels due to solute atoms preferentially coupling to point defect fluxes to defect sinks, such as grain boundaries (GBs). The RIS response of F/M steels and austenitic steels has been shown to be dependent on the local structure of GBs but has only been demonstrated in ion irradiated specimens. A 9 wt. % Cr model alloy steel was irradiated to 3 dpa using neutrons at the Advanced Test Reactor (ATR) to determine the effect of neutron radiation environment on the RIS-GB structure dependence. This investigation found the relationship between GB structure and RIS is also active for F/M steels irradiated using neutrons. The data generated from the neutron irradiation is also compared to RIS data generated using proton irradiations on the same heat of model alloy.

Field, Kevin G [ORNL] [ORNL; Miller, Brandon [Idaho National Laboratory (INL)] [Idaho National Laboratory (INL); Chichester, Heather J.M. [Idaho National Laboratory (INL)] [Idaho National Laboratory (INL); Sridharan, K. [University of Wisconsin, Madison] [University of Wisconsin, Madison; Allen, Todd R. [University of Wisconsin, Madison] [University of Wisconsin, Madison

2014-01-01T23:59:59.000Z

163

Induction of nuclear factor kB after low-dose ionizing radiation involves a reactive oxygen intermediate signaling pathway  

Science Conference Proceedings (OSTI)

Reactive oxygen intermediates (ROIs) have been found to be the messengers in the activation of the kB transcription regulator in mitogen- or cytokine-stimulated cells, operating in conjunction with or independently of various other mechanisms; these include Ca{sup ++}-dependent and PKC-dependent cytoplasmic signaling pathways. We have recently reported that low-dose ionizing radiation induces NF-kB in human lymphoblastoid 244B cells. Since ionizing radiation generates free radicals in cells, we have investigated whether the ROIs generated by ionizing radiation induce NF-kB activity, and also whether they do so by a similar mechanism as in cells treated with PMA or H{sub 2}O{sub 2}. The results not only confirm a previous observation from our laboratory that low-dose ionizing radiation (0.1-2.0 Gy) activates kB transcription factor transiently with a maximal induction at 0.5 Gy exposure, but also demonstrate mechanistically that the activation of NF-kB by low-dose ionizing radiation can be inhibited considerably by the antioxidant N-acetyl-L-cysteine, indicating that at least the major part of the activation process is mediated by ROIs. These findings support the idea that ROIs can regulate the kB elements which in turn can serve as response elements for oxidant stress. 37 refs., 4 figs., 1 tab.

Mohan, N.; Meltz, M.L. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

1994-10-01T23:59:59.000Z

164

Low Dose Radiation Research Program: A Variable Energy Soft X-ray  

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

Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kevin M Prise and Barry D Michael. Institutions: Gray Cancer Institute. We are currently engaged on two projects in the Low-dose Program: "Low dose studies with focused X-rays in cell and tissue models: mechanisms of bystander and genomic instability responses" (DE-FG07-99ER62877) and "Mechanistic modeling of bystander effects: An integrated theoretical and experimental approach" (DE-FG02-02ER63305). Central to both of these studies is a unique micro irradiation facility that uses ultrasoft X-rays focused to a sub micron beam for individual cell and sub cellular targeting. This facility allows us to selectively irradiate individual

165

Low Dose Radiation Research Program: Role of TNF-α as a Potential  

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

Role of TNF-α as a Potential Signaling Mediator of Role of TNF-α as a Potential Signaling Mediator of Radiation-Induced Bystander Effect in Human Vascular Cells. Authors: Mohan Natarajan, Sumathy Mohan, Catherine Gibbons, Yan Bo and Munira A. Kadhim Institutions: Departments of Radiation Oncology and Pathology, University of Texas Health Science Center, San Antonio, Texas; Environmental Toxicology Graduate Program, University of California, Riverside; Radiation and Genomic Stability Unit, Medical research Council, Oxford, United Kingdom Identifying reliable and sensitive signaling pathways that are implicated in adverse health effects after exposure to low doses of ionizing radiation would allow us to understand the scientific basis of low dose-induced signaling pathways and their downstream phenotypic expression. This

166

Low Dose Radiation Stimulates Antioxidant Capacity in the Brain and Lessens  

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Stimulates Antioxidant Capacity in the Brain and Lessens Stimulates Antioxidant Capacity in the Brain and Lessens Behavioral Symptoms in a 6-OHDA-Induced Rat Model of Parkinson's Disease Mohan Doss Fox Chase Cancer Center Abstract Background: Progressive degeneration of dopaminergic neurons in the substantia nigra (SN) pars compacta results in motor deficits in Parkinson’s disease (PD) patients. Oxidative damage to the nigral dopaminergic neurons has been implicated in the pathogenesis of Parkinson’s disease. Our hypothesis is that low dose radiation induces the production of antioxidants in the brain, which could provide protection to the dopaminergic neurons, potentially leading to prevention or stabilization of PD. The purpose of the study is (1) to determine the effect of low dose radiation on the total antioxidant capacity in SN in

167

Adaptive Discrete Cosine Transform  

Science Conference Proceedings (OSTI)

The theory and performance of the adaptive discrete cosine transform filter is examined. The discrete cosine transform filter is a realization of an FIR filter as the cascade of an all-zero FIR filter with a bank of IIR digital resonators. Each bank ... Keywords: FIR filter, IIR digital resonators, LMS algorithm, adaptive discrete cosine transform filter, adaptive filters, all-zero FIR filter, filter coefficient, frequency, magnitude, phase, transfer function, update method

S. J. Bukowinski; L. Gerhardt; M. Fargues; G. Coutu

1995-10-01T23:59:59.000Z

168

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

169

Adaptive Video Retrieval  

E-Print Network (OSTI)

Hopfgartner,F. Villa,R. Urban,J. Jose,J.M. Proceedings of the First International Workshop on Adaptive Information Retrieval pp 28-29

Hopfgartner, F.

170

IN-SITU PROBING OF RADIATION-INDUCED PROCESSING OF ORGANICS IN ASTROPHYSICAL ICE ANALOGS-NOVEL LASER DESORPTION LASER IONIZATION TIME-OF-FLIGHT MASS SPECTROSCOPIC STUDIES  

Science Conference Proceedings (OSTI)

Understanding the evolution of organic molecules in ice grains in the interstellar medium (ISM) under cosmic rays, stellar radiation, and local electrons and ions is critical to our understanding of the connection between ISM and solar systems. Our study is aimed at reaching this goal of looking directly into radiation-induced processing in these ice grains. We developed a two-color laser-desorption laser-ionization time-of-flight mass spectroscopic method (2C-MALDI-TOF), similar to matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) mass spectroscopy. Results presented here with polycyclic aromatic hydrocarbon (PAH) probe molecules embedded in water-ice at 5 K show for the first time that hydrogenation and oxygenation are the primary chemical reactions that occur in astrophysical ice analogs when subjected to Ly{alpha} radiation. We found that hydrogenation can occur over several unsaturated bonds and the product distribution corresponds to their stabilities. Multiple hydrogenation efficiency is found to be higher at higher temperatures (100 K) compared to 5 K-close to the interstellar ice temperatures. Hydroxylation is shown to have similar efficiencies at 5 K or 100 K, indicating that addition of O atoms or OH radicals to pre-ionized PAHs is a barrierless process. These studies-the first glimpses into interstellar ice chemistry through analog studies-show that once accreted onto ice grains PAHs lose their PAH spectroscopic signatures through radiation chemistry, which could be one of the reason for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks.

Gudipati, Murthy S.; Yang Rui, E-mail: gudipati@jpl.nasa.gov, E-mail: ryang73@ustc.edu [University of Maryland (United States)

2012-09-01T23:59:59.000Z

171

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

172

Cell Type-dependent Gene Transcription Profile in Three Dimensional Human Skin Tissue Model Exposed to Low Doses of Ionizing Radiation: Implications for Medical Exposures  

SciTech Connect

The concern over possible health risks from exposures to low doses of ionizing radiation has been driven largely by the increase in medical exposures, the routine implementation of X-ray backscatter devices for airport security screening, and, most recently, the nuclear incident in Japan. Due to a paucity of direct epidemiological data at very low doses, cancer risk must be estimated from high dose exposure scenarios. However, there is increasing evidence that low and high dose exposures result in different signaling events and may have different mechanisms of cancer induction. We have examined the radiation induced temporal response of an in vitro three dimensional (3D) human skin tissue model using microarray-based transcriptional profiling. Our data shows that exposure to 100 mGy of X-rays is sufficient to affect gene transcription. Cell type specific analysis showed significant changes in gene expression with the levels of > 1400 genes altered in the dermis and > 400 genes regulated in the epidermis. The two cell types rarely exhibited overlapping responses at the mRNA level. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) measurements validated the microarray data in both regulation direction and value. Key pathways identified relate to cell cycle regulation, immune responses, hypoxia, reactive oxygen signaling, and DNA damage repair. We discuss in particular the role of proliferation and emphasizing how the disregulation of cellular signaling in normal tissue may impact progression towards radiation induced secondary diseases.

Freiin von Neubeck, Claere H.; Shankaran, Harish; Karin, Norman J.; Kauer, Paula M.; Chrisler, William B.; Wang, Xihai; Robinson, Robert J.; Waters, Katrina M.; Tilton, Susan C.; Sowa, Marianne B.

2012-04-17T23:59:59.000Z

173

Low Dose Suppression of Neoplastic Transformation in Vitro  

SciTech Connect

This grant was to study the low dose suppression of neoplastic transformation in vitro and the shape of the dose-response curve at low doses and dose-rates of ionizing radiation. Previous findings had indicated a suppression of transformation at dose <10cGy of low-LET radiation when delivered at high dose-rate. The present study indicates that such suppression extends out to doses in excess of 100cGy when the dose (from I-125 photons) is delivered at dose-rates as low as 0.2 mGy/min and out to in excess of {approx}25cGy the highest dose studied at the very low dose-rate of 0.5 mGy/day. We also examined dose-rate effects for high energy protons (which are a low-LET radiation) and suppression was evident below {approx}10cGy for high dose-rate delivery and at least out to 50cGy for low dose-rate (20cGy/h) delivery. Finally, we also examined the effect of low doses of 1 GeV/n iron ions (a high-LET radiation) delivered at high dose-rate on transformation at low doses and found a suppression below {approx}10cGy that could be attributable to an adaptive response in bystander cells induced by the associated low-LET delta rays. These results have implications for cancer risk assessment at low doses.

John Leslie Redpath

2012-05-01T23:59:59.000Z

174

Low-dose computed tomography image restoration using previous normal-dose scan  

Science Conference Proceedings (OSTI)

Purpose: In current computed tomography (CT) examinations, the associated x-ray radiation dose is of a significant concern to patients and operators. A simple and cost-effective means to perform the examinations is to lower the milliampere-seconds (mAs) or kVp parameter (or delivering less x-ray energy to the body) as low as reasonably achievable in data acquisition. However, lowering the mAs parameter will unavoidably increase data noise and the noise would propagate into the CT image if no adequate noise control is applied during image reconstruction. Since a normal-dose high diagnostic CT image scanned previously may be available in some clinical applications, such as CT perfusion imaging and CT angiography (CTA), this paper presents an innovative way to utilize the normal-dose scan as a priori information to induce signal restoration of the current low-dose CT image series. Methods: Unlike conventional local operations on neighboring image voxels, nonlocal means (NLM) algorithm utilizes the redundancy of information across the whole image. This paper adapts the NLM to utilize the redundancy of information in the previous normal-dose scan and further exploits ways to optimize the nonlocal weights for low-dose image restoration in the NLM framework. The resulting algorithm is called the previous normal-dose scan induced nonlocal means (ndiNLM). Because of the optimized nature of nonlocal weights calculation, the ndiNLM algorithm does not depend heavily on image registration between the current low-dose and the previous normal-dose CT scans. Furthermore, the smoothing parameter involved in the ndiNLM algorithm can be adaptively estimated based on the image noise relationship between the current low-dose and the previous normal-dose scanning protocols. Results: Qualitative and quantitative evaluations were carried out on a physical phantom as well as clinical abdominal and brain perfusion CT scans in terms of accuracy and resolution properties. The gain by the use of the previous normal-dose scan via the presented ndiNLM algorithm is noticeable as compared to a similar approach without using the previous normal-dose scan. Conclusions: For low-dose CT image restoration, the presented ndiNLM method is robust in preserving the spatial resolution and identifying the low-contrast structure. The authors can draw the conclusion that the presented ndiNLM algorithm may be useful for some clinical applications such as in perfusion imaging, radiotherapy, tumor surveillance, etc.

Ma, Jianhua; Huang, Jing; Feng, Qianjin; Zhang, Hua; Lu, Hongbing; Liang, Zhengrong; Chen, Wufan [Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515, China and Department of Radiology, State University of New York, Stony Brook, New York 11794 (United States); Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515 (China); Department of Biomedical Engineering, Fourth Military Medical University, Xi'An, Shanxi 710032 (China); Department of Radiology, State University of New York, Stony Brook, New York 11794 (United States); Department of Biomedical Engineering, Southern Medical University, Guangzhou, Guangdong 510515 (China)

2011-10-15T23:59:59.000Z

175

Radiation-induced gene responses  

SciTech Connect

In the process of identifying genes that are differentially regulated in cells exposed to ultraviolet radiation (UV), we identified a transcript that was repressed following the exposure of cells to a combination of UV and salicylate, a known inhibitor of NF-kappaB. Sequencing this band determined that it has identify to lactate dehydrogenase, and Northern blots confirmed the initial expression pattern. Analysis of the sequence of the LDH 5` region established the presence of NF-kappaB, Sp1, and two Ap-2 elements; two partial AP- 1; one partial RE, and two halves of E-UV elements were also found. Electromobility shift assays were then performed for the AP-1, NF- kappaB, and E-UV elements. These experiments revealed that binding to NF-kappaB was induced by UV but repressed with salicylic acid; UV did not affect AP-1 binding, but salicylic acid inhibited it alone or following UV exposure; and E-UV binding was repressed by UV, and salicylic acid had little effect. Since the binding of no single element correlated with the expression pattern of LDH, it is likely that multiple elements govern UV/salicylate-mediated expression.

Woloschak, G.E.; Paunesku, T.; Shearin-Jones, P.; Oryhon, J.

1996-12-31T23:59:59.000Z

176

Relationship of five anthropometric measurements at age 18 to radiation dose among atomic bomb survivors exposed in utero  

SciTech Connect

Five body measurements-standing height, body weight, sitting height, chest circumference and intercristal diameter-of 18-year-old atomic bomb survivors exposed in utero in Hiroshima and Nagasaki were analyzed in relation to DS86 uterine dose. Age in utero was divided into four periods: 0-7, 8-15, 16-25 and [>=]26 weeks. This categorization is based upon the study of radiation-induced brain damage. The linear regression analyses for these five variables showed significant decreases with increasing dose. The regression coefficients were -2.65 cm/Gy for standing height, -2.46 kg/Gy for body weight, -0.92 cm/Gy for sitting height, -1.37 cm/Gy for chest circumference and -0.32 cm/Gy for intercristal diameter. The multivariate test statistic for the overall dose effect on five body measurements was significant, but the interaction between dose and gestational period was not significant. Principal-component analysis was applied to the five variables. For the first-component scores, the dose effect was significant, but the interaction between dose and gestational period was not significant. For the second-component scores, the dose effect was significant specifically at 0.7 weeks. The radiation dose effect on the second principal component found at 0-7 weeks of gestation suggests that malformation occur in this period. 17 refs., 2 figs., 4 tabs.

Nakashima, Eiji (Radiation Effects Research Foundation, Minami-ku (Japan))

1994-04-01T23:59:59.000Z

177

Mitochondrial-Derived Oxidants and Cellular Responses to Low Dose/Low LET Ionizing Radiation  

SciTech Connect

Exposure to ionizing radiation results in the immediate formation of free radicals and other reactive oxygen species (ROS). It has been assumed that the subsequent injury processes leading to genomic instability and carcinogenesis following radiation, derive from the initial oxidative damage caused by these free radicals and ROS. It is now becoming increasingly obvious that metabolic oxidation/reduction (redox) reactions can be altered by irradiation leading to persistent increases in steady-state levels of intracellular free radicals and ROS that contribute to the long term biological effects of radiation exposure by causing chronic oxidative stress. The objective during the last period of support (DE-FG02-05ER64050; 5/15/05-12/31/09) was to determine the involvement of mitochondrial genetic defects in metabolic oxidative stress and the biological effects of low dose/low LET radiation. Aim 1 was to determine if cells with mutations in succinate dehydrogenase (SDH) subunits C and D (SDHC and SDHD in mitochondrial complex II) demonstrated increases in steady-state levels of reactive oxygen species (ROS; O2- and H2O2) as well as demonstrating increased sensitivity to low dose/low LET radiation (10 cGy) in cultured mammalian cells. Aim #2 was to determine if mitochondrially-derived ROS contributed to increased sensitivity to low dose/low LET radiation in mammalian cells containing mutations in SDH subunits. Aim #3 was to determine if a causal relationship existed between increases in mitochondrial ROS production, alterations in electron transport chain proteins, and genomic instability in the progeny of irradiated cells. Evidence gathered in the 2005-2009 period of support demonstrated that mutations in genes coding for mitochondrial electron transport chain proteins (ETC); either Succinate Dehydrogenase (SDH) subunit C (SDHC) or subunit D (SDHD); caused increased ROS production, increased genomic instability, and increased sensitivity to low dose/low LET radiation that could be mitigated by over expression of the H2O2 metabolizing enzyme, catalase, and/or the mitochondrial form of superoxide dismutase (MnSOD). Furthermore, using radiation-induced genomically unstable cells, it was shown that steady-state levels of H2O2 were significantly elevated for many cell generations following exposure, catalase suppressed the radiation-induced mutator phenotype when added long after radiation exposure, unstable clones showed evidence of mitochondrial dysfunction some of which was characterized by improper assembly of SDH subunits (particularly subunit B), and chemical inhibitors of SDH activity could decrease steady-state levels of H2O2 as well as mutation frequency. These results support the hypotheses that 1) SDH mutations could contribute to transformation by inducing genomic instability and a mutator phenotype via increasing steady-state levels of ROS; 2) metabolic sources of O2- and H2O2 play a significant role in low dose radiation induced injury and genomic instability; and 3) increased mutation rates in irradiated mammal cells can be suppressed by scavengers of H2O2 (particularly catalase) long after radiation exposure. Overall the results obtained during this period of support provide clear evidence in support of the hypothesis that abnormal oxidative metabolism in mitochondria that result in increases in steady-sate levels of H2O2 and other ROS are capable of significantly contributing to radiation-induced mutator phenotypes in mammalian cells.

Spitz, Douglas R.

2009-11-09T23:59:59.000Z

178

Plastic packaging and burn-in effects on ionizing dose response in CMOS microcircuits  

Science Conference Proceedings (OSTI)

Results are reported from an investigation of the effects of packaging and burn-in on the post-irradiation performance of National Semiconductor 54AC02 Quad 2-input NOR gates. The test population was drawn from a single wafer fabricated in the National process qualified under Mil-Prf-38535 to an ionizing radiation hardness of 100 krads(Si). The test sample was divided between plastic and ceramic packages. Additionally, half of the plastic samples and half of the two ceramic samples received a 168 hour/125 C burn-in. Two irradiation schemes were used. The first followed Mil-Std-883 Method 1019.4 (dose rate = 50 rads(Si)/s). The second used a low dose rate (0.1 rads(Si)/s). AC, DC, transfer function and functional behavior were monitored throughout the tests. Significant differences among the package types and burn-in variations were noted with the plastic, burned-in components demonstrating enhanced degradation. They show the worst post-irradiation parameter values as well as very broad post-irradiation parameter distributions. Degradation is highly dependent upon dose rate and anneal conditions. Two different radiation induced leakage paths have been identified, and their characteristics have been correlated to variations in high dose rate and low dose rate circuit performance. Caution is recommended for system developers to ensure that radiation hardness characterization is performed for the same package/burn-in configuration to be used in the system.

Clark, S.D.; Bings, J.P. [Naval Surface Warfare Center, Crane, IN (United States). Crane Div.; Maher, M.C.; Williams, M.K.; Alexander, D.R.; Pease, R.L.

1995-12-01T23:59:59.000Z

179

Leak test adapter for containers  

DOE Patents (OSTI)

An adapter is provided for facilitating the charging of containers and leak testing penetration areas. The adapter comprises an adapter body and stem which are secured to the container`s penetration areas. The container is then pressurized with a tracer gas. Manipulating the adapter stem installs a penetration plug allowing the adapter to be removed and the penetration to be leak tested with a mass spectrometer. Additionally, a method is provided for using the adapter. The present invention relates generally to leak test adapters, and more particularly to leak test adapters used with containers such as radioactive material shipping containers.

Hallett, B.H.; Hartley, M.S.

1995-12-31T23:59:59.000Z

180

Optical Military Systems Adaptive  

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

turbulence in ground-based telescopes or to improve the spatial mode and power of lasers. More recently, Sandia has led the innovation of using adaptive elements, such as...

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

High-Dose Dosimetry  

Science Conference Proceedings (OSTI)

... web page below. Service descriptions and price schedule for NIST high-dose services are found in this link. The intention ...

2013-03-01T23:59:59.000Z

182

Study of radiation effects on the cell structure and evaluation of the dose delivered by x-ray and {alpha}-particles microscopy  

SciTech Connect

Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to study radiation effects on cells. Experiments were performed on freeze-dried cells at the nano-imaging station ID22NI of the European synchrotron radiation facility. Quantitative phase contrast imaging provides maps of the projected mass and is used to evaluate the structural changes due to irradiation during X-ray fluorescence experiments. Complementary to phase contrast imaging, scanning transmission ion microscopy is performed and doses of all the experiments are compared. We demonstrate the sensitivity of the proposed approach to study radiation-induced damage at the sub-cellular level.

Kosior, Ewelina; Cloetens, Peter [European Synchrotron Radiation Facility, F-38000 Grenoble (France); Deves, Guillaume; Ortega, Richard [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Bohic, Sylvain [European Synchrotron Radiation Facility, 38000 Grenoble (France); INSERM U-836 (Team 6: Synchrotron Radiation and Medical Research), Grenoble Institut of Neuroscience, F-38000 Grenoble (France)

2012-12-24T23:59:59.000Z

183

Automated size-specific CT dose monitoring program: Assessing variability in CT dose  

SciTech Connect

Purpose: The potential health risks associated with low levels of ionizing radiation have created a movement in the radiology community to optimize computed tomography (CT) imaging protocols to use the lowest radiation dose possible without compromising the diagnostic usefulness of the images. Despite efforts to use appropriate and consistent radiation doses, studies suggest that a great deal of variability in radiation dose exists both within and between institutions for CT imaging. In this context, the authors have developed an automated size-specific radiation dose monitoring program for CT and used this program to assess variability in size-adjusted effective dose from CT imaging. Methods: The authors radiation dose monitoring program operates on an independent health insurance portability and accountability act compliant dosimetry server. Digital imaging and communication in medicine routing software is used to isolate dose report screen captures and scout images for all incoming CT studies. Effective dose conversion factors (k-factors) are determined based on the protocol and optical character recognition is used to extract the CT dose index and dose-length product. The patient's thickness is obtained by applying an adaptive thresholding algorithm to the scout images and is used to calculate the size-adjusted effective dose (ED{sub adj}). The radiation dose monitoring program was used to collect data on 6351 CT studies from three scanner models (GE Lightspeed Pro 16, GE Lightspeed VCT, and GE Definition CT750 HD) and two institutions over a one-month period and to analyze the variability in ED{sub adj} between scanner models and across institutions. Results: No significant difference was found between computer measurements of patient thickness and observer measurements (p= 0.17), and the average difference between the two methods was less than 4%. Applying the size correction resulted in ED{sub adj} that differed by up to 44% from effective dose estimates that were not adjusted by patient size. Additionally, considerable differences were noted in ED{sub adj} distributions between scanners, with scanners employing iterative reconstruction exhibiting significantly lower ED{sub adj} (range: 9%-64%). Finally, a significant difference (up to 59%) in ED{sub adj} distributions was observed between institutions, indicating the potential for dose reduction. Conclusions: The authors developed a robust automated size-specific radiation dose monitoring program for CT. Using this program, significant differences in ED{sub adj} were observed between scanner models and across institutions. This new dose monitoring program offers a unique tool for improving quality assurance and standardization both within and across institutions.

Christianson, Olav; Li Xiang; Frush, Donald; Samei, Ehsan [Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 and Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States) and Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Department of Physics, Duke University, Durham, North Carolina 27710 (United States); and Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708 (United States)

2012-11-15T23:59:59.000Z

184

The Climate Adaptation Frontier  

Science Conference Proceedings (OSTI)

Climate adaptation has emerged as a mainstream risk management strategy for assisting in maintaining socio-ecological systems within the boundaries of a safe operating space. Yet, there are limits to the ability of systems to adapt. Here, we introduce the concept of an adaptation frontier , which is defined as a socio-ecological system s transitional adaptive operating space between safe and unsafe domains. A number of driving forces are responsible for determining the sustainability of systems on the frontier. These include path dependence, adaptation/development deficits, values conflicts and discounting of future loss and damage. The cumulative implications of these driving forces are highly uncertain. Nevertheless, the fact that a broad range of systems already persist at the edge of their frontiers suggests a high likelihood that some limits will eventually be exceeded. The resulting system transformation is likely to manifest as anticipatory modification of management objectives or loss and damage. These outcomes vary significantly with respect to their ethical implications. Successful navigation of the adaptation frontier will necessitate new paradigms of risk governance to elicit knowledge that encourages reflexive reevaluation of societal values that enable or constrain sustainability.

Preston, Benjamin L [ORNL

2013-01-01T23:59:59.000Z

185

SCIENTIFIC CORRESPONDENCE Radiation doses  

E-Print Network (OSTI)

-- ation doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk-dose groups. Unfortunately, they did not report the number in the workforce. Pending release of the full data' Forschungsergebmsse All (1972). 2.Hunter J. R.. Unesco Reports m Marine Soence 28, (1984). 3. Hassan. E. M. & Hassan

Shlyakhter, Ilya

186

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

187

Low Dose Radiation Research Program: A Variable-Energy Soft X-Ray  

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

A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kirk Atkinson, Kevin M Prise, Barry D Michael Institutions: Gray Cancer Institute, PO BO Box100, Mount Vernon Hospital, Northwood, HA6 2JR, UK The Gray Cancer Institute (GCI) has pioneered the use of X-ray focussing techniques to develop systems for micro-irradiating individual cells and sub-cellular targets. Our prototype X-ray microprobe was developed alongside our existing charged-particle microbeam to address problems specific to low LET radiations, or where very precise targeting accuracy and dose delivery are required. This facility was optimised for focusing 278 eV CK X-rays; however there are a number of reasons for extending the

188

Verification of Adaptive Systems  

SciTech Connect

Adaptive systems are critical for future space and other unmanned and intelligent systems. Verification of these systems is also critical for their use in systems with potential harm to human life or with large financial investments. Due to their nondeterministic nature and extremely large state space, current methods for verification of software systems are not adequate to provide a high level of assurance for them. The combination of stabilization science, high performance computing simulations, compositional verification and traditional verification techniques, plus operational monitors, provides a complete approach to verification and deployment of adaptive systems that has not been used before. This paper gives an overview of this approach.

Pullum, Laura L [ORNL; Cui, Xiaohui [New York Institute of Technology (NYIT); Vassev, Emil [Lero The Irish Software Engineering Research Centre; Hinchey, Mike [Lero The Irish Software Engineering Research Centre; Rouff, Christopher [Lockheed Martin Corporation; Buskens, Richard [Lockheed Martin Corporation

2012-01-01T23:59:59.000Z

189

Adaptive sequential controller  

Science Conference Proceedings (OSTI)

An adaptive sequential controller for controlling a circuit breaker or other switching device to substantially eliminate transients on a distribution line caused by closing and opening the circuit breaker. The device adaptively compensates for changes in the response time of the circuit breaker due to aging and environmental effects. A potential transformer provides a reference signal corresponding to the zero crossing of the voltage waveform, and a phase shift comparator circuit compares the reference signal to the time at which any transient was produced when the circuit breaker closed, producing a signal indicative of the adaptive adjustment that should be made. Similarly, in controlling the opening of the circuit breaker, a current transformer provides a reference signal that is compared against the time at which any transient is detected when the circuit breaker last opened. An adaptive adjustment circuit produces a compensation time that is appropriately modified to account for changes in the circuit breaker response, including the effect of ambient conditions and aging. When next opened or closed, the circuit breaker is activated at an appropriately compensated time, so that it closes when the voltage crosses zero and opens when the current crosses zero, minimizing any transients on the distribution line. Phase angle can be used to control the opening of the circuit breaker relative to the reference signal provided by the potential transformer. 15 figs.

El-Sharkawi, M.A.; Xing, J.; Butler, N.G.; Rodriguez, A.

1994-11-01T23:59:59.000Z

190

Plants remember drought, adapt  

Science Conference Proceedings (OSTI)

Research carried out at the University of Nebraska-Lincoln (UNL; USA) shows that plants subjected to a previous period of drought learn to deal with the stress owing to their memories of the experience. Plants remember drought, adapt Inform Magazine

191

Adaptive sequential controller  

DOE Patents (OSTI)

An adaptive sequential controller (50/50') for controlling a circuit breaker (52) or other switching device to substantially eliminate transients on a distribution line caused by closing and opening the circuit breaker. The device adaptively compensates for changes in the response time of the circuit breaker due to aging and environmental effects. A potential transformer (70) provides a reference signal corresponding to the zero crossing of the voltage waveform, and a phase shift comparator circuit (96) compares the reference signal to the time at which any transient was produced when the circuit breaker closed, producing a signal indicative of the adaptive adjustment that should be made. Similarly, in controlling the opening of the circuit breaker, a current transformer (88) provides a reference signal that is compared against the time at which any transient is detected when the circuit breaker last opened. An adaptive adjustment circuit (102) produces a compensation time that is appropriately modified to account for changes in the circuit breaker response, including the effect of ambient conditions and aging. When next opened or closed, the circuit breaker is activated at an appropriately compensated time, so that it closes when the voltage crosses zero and opens when the current crosses zero, minimizing any transients on the distribution line. Phase angle can be used to control the opening of the circuit breaker relative to the reference signal provided by the potential transformer.

El-Sharkawi, Mohamed A. (Renton, WA); Xing, Jian (Seattle, WA); Butler, Nicholas G. (Newberg, OR); Rodriguez, Alonso (Pasadena, CA)

1994-01-01T23:59:59.000Z

192

IMPRINTED GENES & TRANSPOSITIONS: EPIGENOMIC TARGETS FOR LOW DOSE RADIATION EFFECTS  

Science Conference Proceedings (OSTI)

The overall hypothesis of this grant application is that low dose ionizing radiation (LDIR) elicits adaptive responses in part by causing heritable DNA methylation changes in the epigenome. This novel postulate was tested by determining if the level of DNA methylation at the Agouti viable yellow (A{sup vy}) metastable locus is altered, in a dose-dependent manner, by low dose radiation exposure (radiation hormesis, bringing into question the assumption that every dose of radiation is harmful. Our findings not only have significant implications concerning the mechanism of hormesis, but they also emphasize the potential importance of this phenomenon in determining human risk at low radiation doses. Since the epigenetic regulation of genes varies markedly between species, the effect of LDIR on other epigenetically labile genes (e.g. imprinted genes) in animals and humans needs to be defined.

Randy Jirtle

2012-10-11T23:59:59.000Z

193

New Computational Methods for Characterizing Systems Biology of Low Dose  

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

New Computational Methods for Characterizing Systems Biology of Low Dose New Computational Methods for Characterizing Systems Biology of Low Dose and Adaptive Response Bahram Parvin Lawrence Berkeley National Laboratory Abstract We present preliminary results on a new computational method for systems biology of adaptive response and low dose effect from transcript and phenotypic data. The underlying concept is that a small subset of genes is triggered for each treatment condition or a phenotypic index. The concept of a small subset of genes translates to the sparsity constraint, which is applied computationally. The main advantage of this technique over traditional statistical methods is (i) direct application of sparsity, (ii) incorporating multi-class and multidimensional phenotypic profiles in one framework, and (iii) hypothesizing interaction networks simultaneously. Our

194

Adaptation and adaptability : expectant design for resilience in coastal urbanity  

E-Print Network (OSTI)

What is the nature of and possibility for urban resiliency through adaptation? Adaptation implies responsiveness to phenomena that are disruptive to a system's functioning; it is a willful evolution in response to changed ...

Ruskeep, Laura A. Delaney (Laura Ashley Delaney)

2011-01-01T23:59:59.000Z

195

Systematic measurements of whole-body dose distributions for various treatment machines and delivery techniques in radiation therapy  

Science Conference Proceedings (OSTI)

Purpose: Contemporary radiotherapy treatment techniques, such as intensity-modulated radiation therapy and volumetric modulated arc therapy, could increase the radiation-induced malignancies because of the increased beam-on time, i.e., number of monitor units needed to deliver the same dose to the target and the larger volume irradiated with low doses. In this study, whole-body dose distributions from typical radiotherapy patient plans using different treatment techniques and therapy machines were measured using the same measurement setup and irradiation intention. Methods: Individually calibrated thermoluminescent dosimeters were used to measure absorbed dose in an anthropomorphic phantom at 184 locations. The dose distributions from 6 MV beams were compared in terms of treatment technique (3D-conformal, intensity-modulated radiation therapy, volumetric modulated arc therapy, helical TomoTherapy, stereotactic radiotherapy, hard wedges, and flattening filter-free radiotherapy) and therapy machine (Elekta, Siemens and Varian linear accelerators, Accuray CyberKnife and TomoTherapy). Results: Close to the target, the doses from intensity-modulated treatments (including flattening filter-free) were below the dose from a static treatment plan, whereas the CyberKnife showed a larger dose by a factor of two. Far away from the treatment field, the dose from intensity-modulated treatments showed an increase in dose from stray radiation of about 50% compared to the 3D-conformal treatment. For the flattening filter-free photon beams, the dose from stray radiation far away from the target was slightly lower than the dose from a static treatment. The CyberKnife irradiation and the treatment using hard wedges increased the dose from stray radiation by nearly a factor of three compared to the 3D-conformal treatment. Conclusions: This study showed that the dose outside of the treated volume is influenced by several sources. Therefore, when comparing different treatment techniques, the dose ratios vary with distance to the isocenter. The effective dose outside the treated volume of intensity-modulated treatments with or without flattening filter was 10%-30% larger when compared to 3D-conformal radiotherapy. This dose increase is much lower than the monitor unit scaled effective dose from a static treatment.

Haelg, Roger A.; Besserer, Juergen; Schneider, Uwe [Institute for Radiotherapy, Radiotherapie Hirslanden AG, Aarau 5000 (Switzerland); Vetsuisse Faculty, University of Zurich, Zurich 8057 (Switzerland) and Institute for Radiotherapy, Radiotherapie Hirslanden AG, Aarau 5000 (Switzerland)

2012-12-15T23:59:59.000Z

196

Internal Dose Assessment (IDA) Spreadsheet  

Science Conference Proceedings (OSTI)

The purpose of the Internal Dose Assessment (IDA) Spreadsheet is to calculate internal occupational dose following the methodology described in the EPRI Alpha Monitoring Guidelines.

2007-04-12T23:59:59.000Z

197

Adaptive Constraints for Feature Tracking  

Science Conference Proceedings (OSTI)

In this paper extensions to an existing tracking algorithm are described. These extensions implement adaptive tracking constraints in the form of regional upper-bound displacements and an adaptive track smoothness constraint. Together, these ...

K. I. Hodges

1999-06-01T23:59:59.000Z

198

Dose Reduction Techniques  

SciTech Connect

As radiation safety specialists, one of the things we are required to do is evaluate tools, equipment, materials and work practices and decide whether the use of these products or work practices will reduce radiation dose or risk to the environment. There is a tendency for many workers that work with radioactive material to accomplish radiological work the same way they have always done it rather than look for new technology or change their work practices. New technology is being developed all the time that can make radiological work easier and result in less radiation dose to the worker or reduce the possibility that contamination will be spread to the environment. As we discuss the various tools and techniques that reduce radiation dose, keep in mind that the radiological controls should be reasonable. We can not always get the dose to zero, so we must try to accomplish the work efficiently and cost-effectively. There are times we may have to accept there is only so much you can do. The goal is to do the smart things that protect the worker but do not hinder him while the task is being accomplished. In addition, we should not demand that large amounts of money be spent for equipment that has marginal value in order to save a few millirem. We have broken the handout into sections that should simplify the presentation. Time, distance, shielding, and source reduction are methods used to reduce dose and are covered in Part I on work execution. We then look at operational considerations, radiological design parameters, and discuss the characteristics of personnel who deal with ALARA. This handout should give you an overview of what it takes to have an effective dose reduction program.

WAGGONER, L.O.

2000-05-16T23:59:59.000Z

199

Neutron scattered dose equivalent to a fetus from proton radiotherapy of the mother  

Science Conference Proceedings (OSTI)

Scattered neutron dose equivalent to a representative point for a fetus is evaluated in an anthropomorphic phantom of the mother undergoing proton radiotherapy. The effect on scattered neutron dose equivalent to the fetus of changing the incident proton beam energy, aperture size, beam location, and air gap between the beam delivery snout and skin was studied for both a small field snout and a large field snout. Measurements of the fetus scattered neutron dose equivalent were made by placing a neutron bubble detector 10 cm below the umbilicus of an anthropomorphic Rando[reg] phantom enhanced by a wax bolus to simulate a second trimester pregnancy. The neutron dose equivalent in milliSieverts (mSv) per proton treatment Gray increased with incident proton energy and decreased with aperture size, distance of the fetus representative point from the field edge, and increasing air gap. Neutron dose equivalent to the fetus varied from 0.025 to 0.450 mSv per proton Gray for the small field snout and from 0.097 to 0.871 mSv per proton Gray for the large field snout. There is likely to be no excess risk to the fetus of severe mental retardation for a typical proton treatment of 80 Gray to the mother since the scattered neutron dose to the fetus of 69.7 mSv is well below the lower confidence limit for the threshold of 300 mGy observed for the occurrence of severe mental retardation in prenatally exposed Japanese atomic bomb survivors. However, based on the linear no threshold hypothesis, and this same typical treatment for the mother, the excess risk to the fetus of radiation induced cancer death in the first 10 years of life is 17.4 per 10 000 children.

Mesoloras, Geraldine; Sandison, George A.; Stewart, Robert D.; Farr, Jonathan B.; Hsi, Wen C. [School of Health Sciences, Purdue University, West Lafayette, Indiana 47906 (United States); Midwest Proton Radiotherapy Institute (MPRI), Bloomington, Indiana 47408 (United States)

2006-07-15T23:59:59.000Z

200

Raman spectroscopy of tumour cells exposed to clinically relevant doses of ionizing radiation.  

E-Print Network (OSTI)

??Improvements to radiation therapy treatment outcomes rely, in part, on consideration of patient specific radiosensitivity. Therefore an assay which quantifies radiation-induced biochemical changes, and subsequently (more)

Harder, Samantha

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

External Dose Estimates from  

E-Print Network (OSTI)

Appendix E External Dose Estimates from NTS Fallout E-1 #12;External Radiation Exposure as the dependence on fallout time of arrival. The most exposed individuals were outdoor workers; the least exposed was about a factor of 20 less than that from "global fallout" from high- yield weapons tests carried out

202

External Dose Estimates from  

E-Print Network (OSTI)

Appendix G External Dose Estimates from Global Fallout G-1 #12;External Radiation Exposure from the fallout from all of these tests was about 0.7 mSv, about equivalent to 2-3 years of external radiation exposure from natural background. In contrast to the fallout from tests at the Nevada Test site

203

When is a dose not a dose  

Science Conference Proceedings (OSTI)

Although an enormous amount of progress has been made in the fields of radiation protection and risk assessment, a number of significant problems remain. The one problem which transcends all the rest, and which has been subject to considerable misunderstanding, involves what has come to be known as the 'linear non-threshold hypothesis', or 'linear hypothesis'. Particularly troublesome has been the interpretation that any amount of radiation can cause an increase in the excess incidence of cancer. The linear hypothesis has dominated radiation protection philosophy for more than three decades, with enormous financial, societal and political impacts and has engendered an almost morbid fear of low-level exposure to ionizing radiation in large segments of the population. This document presents a different interpretation of the linear hypothesis. The basis for this view lies in the evolution of dose-response functions, particularly with respect to their use initially in the context of early acute effects, and then for the late effects, carcinogenesis and mutagenesis. 11 refs., 4 figs. (MHB)

Bond, V.P.

1991-01-01T23:59:59.000Z

204

Radiation leukaemogenesis at low doses DE-FG02-05 ER 63947 Final Technical Report 15 May 2005 ???????????????¢???????????????????????????????? 14 May 2010  

Science Conference Proceedings (OSTI)

This report provides a complete summary of the work undertaken and results obtained under US Department of Energy grant DF-FG02-05 ER 63947, Radiation leukaemogenesis at low doses. There is ample epidemiological evidence indicating that ionizing radiation is carcinogenic in the higher dose range. This evidence, however, weakens and carries increasing uncertainties at doses below 100-200 mSv. At these low dose levels the form of the dose-response curve for radiation-induced cancer cannot be determined reliably or directly from studies of human populations. Therefore animal, cellular and other experimental systems must be employed to provide supporting evidence on which to base judgements of risk at low doses. Currently in radiological protection a linear non-threshold (LNT) extrapolation of risk estimates derived from human epidemiological studies is used to estimate risks in the dose range of interest for protection purposes. Myeloid leukaemias feature prominently among the cancers associated with human exposures to ionising radiation (eg UNSCEAR 2006; IARC 2000). Good animal models of radiation-induced acute myeloid leukaemia (AML) are available including strains such as CBA, RFM and SJL (eg Major and Mole 1978; Ullrich et al 1976; Resnitzky et al 1985). Early mechanistic studies using cytogenetic methods in these mouse models established that the majority of radiation-induced AMLs carried substantial interstitial deletions in one copy of chromosome (chr) 2 (eg Hayata et al 1983; Trakhtenbrot et al 1988; Breckon et al 1991; Rithidech et al 1993; Bouffler et al 1996). Chr2 aberrations are known to occur in bone marrow cells as early as 24 hours after in vivo irradiation (Bouffler et al 1997). Subsequent molecular mapping studies defined a distinct region of chr2 that is commonly lost in AMLs (Clark et al 1996; Silver et al 1999). Further, more detailed, analysis identified point mutations at a specific region of the Sfpi1/PU.1 haemopoietic transcription factor gene which lies in the commonly deleted region of chr2 (Cook et al 2004; Suraweera et al 2005). These lines of evidence strongly implicate the Sfpi1/PU.1 gene as a tumour suppressor gene, dysregulation of which leads to myeloid leukaemia. The main focus of this project was to utilize the CBA mouse model of radiation leukaemogenesis to explore mechanisms of low dose and low dose-rate leukaemogenesis. A series of mechanistic investigations were undertaken, the central aim of which was to identify the events that convert normal cells into myeloid leukaemia cells and explore the dose-response relationships for these. Much of the work centred on the Sfpi1/PU.1 gene and its role in leukaemogenesis. Specific studies considered the dose-response and time-course relationships for loss of the gene, the functional consequences of Sfpi1/PU.1 loss and mutation on transcriptional programmes and developing an in vivo reporter gene system for radiation-induced alterations to PU.1 expression. Additional work sought further genetic changes associated with radiation-induced AMLs and a better characterization of the cell of origin or 'target cell' for radiation-induced AML. All the information gathered is of potential use in developing biologically realistic mathematical models for low dose cancer risk projection.

Simon Bouffler

2010-07-28T23:59:59.000Z

205

An internal dose monitoring program at an academic research institution  

E-Print Network (OSTI)

This thesis describes the development of an internal dose monitoring program for radioactive material based on the recommendations of the International Commission on Radiological Protection (ICRP) in Publication 26, "Recommendations of the International Commission on Radiological Protection" and the regulatory requirements contained in Title 10, Part 20 of the Code of Federal Regulations, "Standards for Protection Against Radiation". The elements of an internal dose monitoring program were reviewed as a prelude to evaluating the internal dose monitoring program at Texas A&M University. A revised internal dose monitoring program was proposed. Identification of individuals required to participate in the internal dose monitoring program was based on methodology adapted from NUREG 1400, "Air Sampling in the Workplace". A review of radioactive material use for 1996 and the bioassay records from 1980 through 1996 was used to determine radionuclide use levels to identify participants eligible for routine and confirmatory bioassays and to develop a schedule for monitoring personnel who are eligible for bioassays. Methods to calculate intake and assess dose using bioassay data were chosen. Action levels were established as percentages of the applicable regulatory dose limits. Bioassay report forms were developed and the requirements for recording results and reporting the dose assessment to regulatory agencies were established.

Carsten, Keith Eric

1997-01-01T23:59:59.000Z

206

Low Dose Radiation Response Curves, Networks and Pathways in Human Lymphoblastoid Cells Exposed from 1 to 10 cGy of Acute Gamma Radiation  

E-Print Network (OSTI)

R.B. Mikkelsen, Ionizing radiation-induced, mitochondria-W.K. Rorrer, P.B. Chen, Radiation-induced proliferation ofresponse genes to ionizing radiation in human lymphoblastoid

Wyrobek, A. J.

2011-01-01T23:59:59.000Z

207

Adaptive control for energy conservation  

DOE Green Energy (OSTI)

The objective of this project is to investigate the use of adaptive control concepts in buildings with solar-assisted heating, ventilating, and air-conditioning (HVAC) systems to maintain occupant comfort conditions while minimizing auxiliary energy use. Accomplishing this objective requires an energy management system capable of making sound tradeoffs. Optimal control theory is used along with a system identification technique to provide an adaptable stratgy. The resulting overall approach is known as adaptive optimal control (AOC).

Farris, D.R.

1980-03-01T23:59:59.000Z

208

Adaptive capacity and its assessment  

SciTech Connect

This paper reviews the concept of adaptive capacity and various approaches to assessing it, particularly with respect to climate variability and change. I find that adaptive capacity is a relatively under-researched topic within the sustainability science and global change communities, particularly since it is uniquely positioned to improve linkages between vulnerability and resilience research. I identify opportunities for advancing the measurement and characterization of adaptive capacity by combining insights from both vulnerability and resilience frameworks, and I suggest several assessment approaches for possible future development that draw from both frameworks and focus on analyzing the governance, institutions, and management that have helped foster adaptive capacity in light of recent climatic events.

Engle, Nathan L.

2011-04-20T23:59:59.000Z

209

Profile-Based Adaption . . .  

E-Print Network (OSTI)

Cache decay is a set of leakage-reduction mechanisms that put cache lines that have not been accessed for a specific duration into a low-leakage standby mode. This duration is called the decay interval, and its optimal value varies across applications. This paper provides an extended discussion of the results previously presented in our journal paper [13]. It describes an adaptation technique that analytically finds the optimal decay interval through profiling, and shows that the most important variables required for finding the optimal decay interval can be estimated with a reasonable degree of accuracy using profiling. This work explicitly trades off the leakage power saved in putting both the live and dead lines into standby mode, against its performance and energy costs. It achieves energy savings close to what can be obtained with an omniscient choice of per-benchmark optimal decay interval.

Karthik Sankaranarayanan; Kevin Skadron

2004-01-01T23:59:59.000Z

210

Biological Basis for Radiation Adaptive Responses that Protect Against  

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

Basis for Radiation Adaptive Responses that Protect Against Basis for Radiation Adaptive Responses that Protect Against Bronchial Epithelial Cell Transformation Wenshu Chen Lovelace Respiratory Research Institute Abstract The major hypothesis in this project is that low-dose, low linear-energy-transfer (LET) radiation stimulates an adaptive response that protects cells from neoplastic transformation involving modulation of paracrine factors (e.g., cytokines), cell survival/death signaling pathways, and reprogramming of the epigenome. To test this hypothesis, a validated, sensitive in vitro transformation model and a media transfer method were used to study the mechanisms of low-LET gamma radiation activated natural protection (ANP) against chemical carcinogen-induced bronchial cell transformation. Immortalized human bronchial epithelial cell

211

Adaptive neuro fuzzy controller for adaptive compliant robotic gripper  

Science Conference Proceedings (OSTI)

The requirement for new flexible adaptive grippers is the ability to detect and recognize objects in their environments. It is known that robotic manipulators are highly nonlinear systems, and an accurate mathematical model is difficult to obtain, thus ... Keywords: ANFIS controller, Adaptive compliant gripper, Embedded sensors, Fuzzy logic, Object recognizing

Dalibor Petkovi?; Mirna Issa; Nenad D. Pavlovi?; Lena Zentner; Arko OjbaI?

2012-12-01T23:59:59.000Z

212

Evidence of radiation-induced reduction of height and body weight from repeated measurements of adults exposed in childhood to the atomic bombs  

Science Conference Proceedings (OSTI)

Reduction of growth from exposure to atomic bomb radiation has been examined using individuals under 10 years old at the time of the bombing (ATB) and a growth curve analysis based on measurements of height and weight made in the course of the 4th-7th cycles of the Adult Health Study examinations (1964-1972). As expected, the largest difference in growth to emerge is between males and females. However, a highly significant reduction of growth associated with dose (DS86) was observed among those survivors for whom four repeated measurements of height and weight were available. Longitudinal analysis of a more extended data set (n = 821), using expected values based on simple linear regression models fitted to the three available sets of measurements of height and weight on the 254 individuals with a missing measurement, also indicates a significant radiation-related growth reduction. The possible contribution of such factors as poor nutrition and disruption of normal family life in the years immediately after the war is difficult to evaluate, but the effects of socioeconomic factors on the analysis of these data are discussed. 33 refs., 5 figs., 3 tabs.

Otake, Masanori; Funamoto, Sachiyo [Radiation Effects Research Foundation, Hiroshima (Japan); Fujikoshi, Yasunori [Hiroshima Univ. (Japan); Schull, W.J. [Univ. of Texas Health Science Center, Houston, TX (United States)

1994-10-01T23:59:59.000Z

213

Voxel-Based Dose Reconstruction for Total Body Irradiation With Helical TomoTherapy  

SciTech Connect

Purpose: We have developed a megavoltage CT (MVCT)-based dose reconstruction strategy for total body irradiation (TBI) with helical TomoTherapy (HT) using a deformable registration model to account for the patient's interfraction changes. The proposed technique serves as an efficient tool for delivered dose verification and, potentially, plan adaptation. Methods and Materials: Four patients with acute myelogenous leukemia treated with TBI using HT were selected for this study. The prescription was 12 Gy, 2 Gy/fraction, twice per day, given at least 6 h apart. The original plan achieved coverage of 80% of the clinical target volume (CTV) by the 12 Gy isodose surface. MVCTs were acquired prior to each treatment. Regions of interest were contoured on each MVCT. The dose for each fraction was calculated based on the MVCT using the HT planned adaptive station. B-spline deformable registration was conducted to establish voxel-to-voxel correspondence between the MVCT and the planning CT. The resultant deformation vector was employed to map the reconstructed dose from each fraction to the same point as the plan dose, and a voxel-to-voxel summed dose from all six fractions was obtained. The reconstructed dose distribution and its dosimetric parameters were compared with those of the original treatment plan. Results: While changes in CTV contours occurred in all patients, the reconstructed dose distribution showed that the dose-volume histogram for CTV coverage was close (<1.5%) to that of the original plan. For sensitive structures, the differences between the reconstructed and the planned doses were less than 3.0%. Conclusion: Voxel-based dose reconstruction strategy that takes into account interfraction anatomical changes using MVCTs is a powerful tool for treatment verification of the delivered doses. This proposed technique can also be applied to adaptive TBI therapy using HT.

Chao Ming, E-mail: mchao@uams.edu [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7199 (United States); Penagaricano, Jose; Yan Yulong; Moros, Eduardo G.; Corry, Peter; Ratanatharathorn, Vaneerat [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7199 (United States)

2012-04-01T23:59:59.000Z

214

Operational dose rate visualization techniques  

SciTech Connect

The analysis of the gamma ray dose rate in the vicinity of a radiation source can be greatly aided by the use of recent state-of-the-art visualization techniques. The method involves calculating dose rates at thousands of locations within a complex geometry system. This information is then processed to create contour plots of the dose rate. Additionally, when these contour plots are created, animations can be created that dynamically display the dose rate as the shields or sources are moved.

Schwarz, R.A.; Morford, R.J.; Carter, L.L.; Jones, G.B.; Greenborg, J.

1994-01-01T23:59:59.000Z

215

Hanford Environmental Dose Reconstruction Project  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): Source terms; environmental transport environmental monitoring data; demographics, agriculture, food habits; environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. (comps.)

1991-01-01T23:59:59.000Z

216

Adaptive navigation for autonomous robots  

Science Conference Proceedings (OSTI)

In many robotic exploration missions, robots have to learn specific policies that allow them to: (i) select high level goals (e.g., identify specific destinations), (ii) navigate (reach those destinations), (iii) and adapt to their environment (e.g., ... Keywords: Learning, evolution, Learning, neural networks, Learning, single agent, Robotics, adaptation

Matt Knudson; Kagan Tumer

2011-06-01T23:59:59.000Z

217

Tightfit: adaptive parallelization with foresight  

Science Conference Proceedings (OSTI)

Irregular applications often exhibit data-dependent parallelism: Different inputs, and sometimes also different execution phases, enable different levels of parallelism. These changes in available parallelism have motivated work on adaptive concurrency ... Keywords: STM, adaptive software parallelization, data-dependent parallelism, irregular applications, offline learning

Omer Tripp; Noam Rinetzky

2013-08-01T23:59:59.000Z

218

Adaptive kernel principal component analysis  

Science Conference Proceedings (OSTI)

An adaptive kernel principal component analysis (AKPCA) method, which has the flexibility to accurately track the kernel principal components (KPC), is presented. The contribution of this paper may be divided into two parts. First, KPC are recursively ... Keywords: Adaptive method, Kernel principal component, Kernel principal component analysis, Non-stationary data, Recursive algorithm

Mingtao Ding; Zheng Tian; Haixia Xu

2010-05-01T23:59:59.000Z

219

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,

220

Standardized radiological dose evaluations  

SciTech Connect

Following the end of the Cold War, the mission of Rocky Flats Environmental Technology Site changed from production of nuclear weapons to cleanup. Authorization baseis documents for the facilities, primarily the Final Safety Analysis Reports, are being replaced with new ones in which accident scenarios are sorted into coarse bins of consequence and frequency, similar to the approach of DOE-STD-3011-94. Because this binning does not require high precision, a standardized approach for radiological dose evaluations is taken for all the facilities at the site. This is done through a standard calculation ``template`` for use by all safety analysts preparing the new documents. This report describes this template and its use.

Peterson, V.L.; Stahlnecker, E.

1996-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Low Dose Radiation Program: Links - Low Dose Research in Japan...  

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

Low Dose Research in Japan-Institutes and Facilities Atomic Bomb Disease Institute, Nagasaki University Institute for Environmental Sciences (IES) National Institute of...

222

Low Dose Radiation Research Program: Low Dose Radiation Research...  

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

Low Dose Radiation Research: Outreach and Resources Authors: Antone L. Brooks and Lezlie A. Couch Institution: Washington State University Tri-Cities, Richland, Washington The...

223

Adaptive Markets and the New World Order  

E-Print Network (OSTI)

In the adaptive markets hypothesis (AMH) intelligent but fallible investors learn from and adapt to changing economic environments. This implies that markets are not always efficient but are usually competitive and adaptive, ...

Lo, Andrew W.

224

African Adaptation Programme | Open Energy Information  

Open Energy Info (EERE)

Adaptation Programme Adaptation Programme Jump to: navigation, search Logo: African Adaptations Programme Name African Adaptations Programme Agency/Company /Organization United Nations Development Programme, Government of Japan Topics Adaptation, Finance, Implementation, Policies/deployment programs Website http://www.undp-adaptation.org References AAP[1] Overview "UNDP, with funding from the Government of Japan, recently launched a new programme that uses an innovative approach to climate change adaptation in Africa. Under this programme, UNDP will assist 21 African countries in implementing integrated and comprehensive adaptation actions and resilience plans. The projects will ensure that national development processes incorporate climate change risks and opportunities to secure development gains under a

225

A Dynamic Platform for Runtime Adaptation  

E-Print Network (OSTI)

We present a middleware platform for assembling pervasive applications that demand fault-tolerance and adaptivity in distributed, dynamic environments. Unlike typical adaptive middleware approaches, in which sophisticated ...

Pham, Hubert

226

Adaptive Materials Inc | Open Energy Information  

Open Energy Info (EERE)

Zip MI 48108 Product Adaptive Materials Inc (AMI) is a developer of portable fuel cell technology. References Adaptive Materials Inc1 LinkedIn Connections CrunchBase...

227

Mainstreaming Climate Change Adaptation into Development Planning...  

Open Energy Info (EERE)

Mainstreaming Climate Change Adaptation into Development Planning: A Guide for Practitioners Jump to: navigation, search Tool Summary Name: Mainstreaming Climate Change Adaptation...

228

Optimal adaptive control with ?LQG.  

E-Print Network (OSTI)

??This thesis introduces ?LQG, the hyper extension of the Linear Quadratic Gaussian Regulator, for solving general purpose (locally optimal) nonlinear adaptive control on multiple-input multiple-output (more)

Wendt, Luke

2013-01-01T23:59:59.000Z

229

COMMENTARY:Limits to adaptation  

SciTech Connect

An actor-centered, risk-based approach to defining limits to social adaptation provides a useful analytic framing for identifying and anticipating these limits and informing debates over society s responses to climate change.

Preston, Benjamin L [ORNL

2013-01-01T23:59:59.000Z

230

Dose Ranges Chart - May 2010  

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

Charged particle event (Solar flare) dose on moon, no shielding Total Body Irradiation (TBI) Therapy Cancer Epidemiology 3 2 6 1 5 4 Natural background, USA average ...

231

ORISE: Dose modeling and assessments  

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

or state regulatory compliance requirements are being met during the decontamination and decommissioning of nuclear facilities. Dose modeling is an important step in the...

232

Hanford Environmental Dose Reconstruction Project  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Battelle Pacific Northwest Laboratories under contract with the Centers for Disease Control. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): source terms; environmental transport; environmental monitoring data; demography, food consumption, and agriculture; environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. (comps.)

1992-06-01T23:59:59.000Z

233

Adaptive and reverse adaptive responses for chromosomal inversions...  

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

a response which can protect from inversion induction within four hours of high dose irradiation. 0 1 2 3 4 5 6 0 0.01 1 1000 1000+0.01 1000+1 Dose (mGy) M e a n in v e r s io n fr...

234

Adaptive control for energy conservation  

DOE Green Energy (OSTI)

The use of adaptive control techniques is investigated in heating, ventilating, and air cnditioning (HVAC) systems in solar heated and cooled buildings to minimize the consumption of auxiliary energy. Optimal control theory is used in conjunction with the adaptive control techniques to accomplish the minimization of auxiliary energy. The resulting technique is referred to as adaptive optimal control (AOC). This study has been made by computer simulation and is centered on the National Security and Resources Study Center (NSRSC), a large solar heated and cooled building at the Los Alamos Scientific Laboratory (LASL). Simplified models of the building and HVAC system have been developed for both the heating and cooling modes. The control strategies actually used in the NSRSC were simulated in the models and an adaptive optimal controller was developed and also simulated. Simulation runs were made with both the conventional controller and the adaptive controller and performance results of the two simulations were compared. In the first results (obtained using a partial derivative system identification method), the adaptive optimal controller model demonstrated a savings in auxiliary energy of 28.8% for the heating simulation and 18.3% for the cooling simulation when compared to the conventional controller simulation models.

Farris, D.R.

1978-01-01T23:59:59.000Z

235

Low Dose Radiation Program: 2010 Low Dose Radiation Research Program  

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

Low Dose Radiation Research Program Investigators' Workshop Low Dose Radiation Research Program Investigators' Workshop »» Event Slide Show More than 150 people attended this year's workshop, held April 12-14 at the Renaissance M Street Hotel in Washington, D.C. In addition to 34 plenary talks and more than 70 poster presentations made by the program investigators, participants heard guest speakers from the National Cancer Institute and from sister low-dose programs in Europe and Japan. Remarks from DOE Dr. Anna Palmisano, Associate Director, Office of Science, Director for Biological and Environmental Research (BER), welcomed the meeting participants, thanked Low Dose Radiation Research Program Manager Dr. Noelle Metting for her leadership, and acknowledged the importance of the Low Dose Program to DOE because of its unique focus and important role. She

236

WeADAPT | Open Energy Information  

Open Energy Info (EERE)

WeADAPT WeADAPT Jump to: navigation, search Name WeADAPT Agency/Company /Organization weADAPT Sector Energy, Land, Water, Climate Resource Type Training materials, Lessons learned/best practices Website http://www.weadapt.org/ References weADAPT[1] "weADAPT.org is an online 'open space' on climate adaptation issues (including the synergies between adaptation and mitigation) which allows practitioners, researchers and policy makers to access credible, high quality information and to share experiences and lessons learnt with the weADAPT community. It is designed to facilitate learning, exchange, collaboration and knowledge integration to build a professional community of practice on adaptation issues while developing policy-relevant tools and guidance for adaptation planning and decision-making.

237

AfricaAdapt | Open Energy Information  

Open Energy Info (EERE)

AfricaAdapt AfricaAdapt Jump to: navigation, search Logo: Africa Adapt Name Africa Adapt Agency/Company /Organization AfricaAdapt Resource Type Training materials, Lessons learned/best practices Website http://www.africa-adapt.net/AA UN Region Eastern Africa, Middle Africa, Northern Africa, Southern Africa, Western Africa References AfricaAdapt[1] Abstract AfricaAdapt is an independent bilingual network (French/English) focused exclusively on Africa. The Network's aim is to facilitate the flow of climate change adaptation knowledge for sustainable livelihoods between researchers, policy makers, civil society organisations and communities who are vulnerable to climate variability and change across the continent. Africa Adapt Screenshot "AfricaAdapt is an independent bilingual network (French/English) focused

238

Molecular dissection of the roles of the SOD genes in mammalian response to low dose irradiation  

SciTech Connect

It has been long recognized that a significant fraction of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying enzymes may be even more prominent in the case of low-dose, low-LET irradiation, as the majority of genetic damage may be caused by secondary oxidative species. In this study we have attempted to decipher the roles of the superoxide dismutase (SOD) genes, which are responsible for detoxifying the superoxide anions. We used adenovirus vectors to deliver RNA interference (RNAi or siRNA) technology to down-regulate the expression levels of the SOD genes. We have also over-expressed the SOD genes by use of recombinant adenovirus vectors. Cells infected with the vectors were then subjected to low dose ?-irradiation. Total RNA were extracted from the exposed cells and the expression of 9000 genes were profiled by use of cDNA microarrays. The result showed that low dose radiation had clear effects on gene expression in HCT116 cells. Both over-expression and down-regulation of the SOD1 gene can change the expression profiles of sub-groups of genes. Close to 200 of the 9000 genes examined showed over two-fold difference in expression under various conditions. Genes with changed expression pattern belong to many categories that include: early growth response, DNA-repair, ion transport, apoptosis, and cytokine response.

Eric Y. Chuang

2006-08-31T23:59:59.000Z

239

Adaptive Liquid Crystal Windows  

SciTech Connect

Energy consumption by private and commercial sectors in the U.S. has steadily grown over the last decade. The uncertainty in future availability of imported oil, on which the energy consumption relies strongly, resulted in a dramatic increase in the cost of energy. About 20% of this consumption are used to heat and cool houses and commercial buildings. To reduce dependence on the foreign oil and cut down emission of greenhouse gases, it is necessary to eliminate losses and reduce total energy consumption by buildings. To achieve this goal it is necessary to redefine the role of the conventional windows. At a minimum, windows should stop being a source for energy loss. Ideally, windows should become a source of energy, providing net gain to reduce energy used to heat and cool homes. It is possible to have a net energy gain from a window if its light transmission can be dynamically altered, ideally electronically without the need of operator assistance, providing optimal control of the solar gain that varies with season and climate in the U.S. In addition, the window must not require power from the building for operation. Resolution of this problem is a societal challenge and of national interest and will have a broad global impact. For this purpose, the year-round, allclimate window solution to provide an electronically variable solar heat gain coefficient (SHGC) with a wide dynamic range is needed. AlphaMicron, Inc. (AMI) developed and manufactured 1ft 1ft prototype panels for the worlds first auto-adjusting Adaptive Liquid Crystal Windows (ALCWs) that can operate from sunlight without the need for external power source and demonstrate an electronically adjustable SHGC. This novel windows are based on AlphaMicrons patented e-Tint technology, a guesthost liquid crystal system implemented on flexible, optically clear plastic films. This technology is suitable both for OEM and aftermarket (retro-fitting) lamination to new and existing windows. Low level of power consumption by ALCWs allows for on-board power electronics for automatic matching of transmission through windows to varying climate conditions without drawing the power from the power grid. ALCWs are capable of transmitting more sunlight in winters to assist in heating and less sunlight in summers to minimize overheating. As such, they can change the window from being a source of energy loss to a source of energy gain. In addition, the scalable AMIs roll-to-roll process, proved by making 1ft 1ftALCW prototype panels, allows for cost-effective production of large-scale window panels along with capability to change easily their color and shape. In addition to architectural glazing in houses and commercial buildings, ALCWs can be used in other applications where control of sunlight is needed, such as green houses, used by commercial produce growers and botanical gardens, cars, aircrafts, etc.

Taheri, Bahman; Bodnar, Volodymyr

2011-12-31T23:59:59.000Z

240

Adaptive vibration control using synchronous demodulation with ...  

Adaptive vibration control using synchronous demodulation with machine tool controller motor commutation United States Patent

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Checking Properties of Adaptive Workflow Nets  

Science Conference Proceedings (OSTI)

In this paper we consider adaptive workflow nets, a class of nested nets that allows more comfort and expressive power for modeling adaptability and exception handling in workflow nets. We define two important behavioural properties of adaptive workflow ... Keywords: adaptive workflow, circumspectness, soundness, verification

Kees van Hee; Olivia Oanea; Alexander Serebrenik; Natalia Sidorova; Marc Voorhoeve; Irina A. Lomazova

2008-02-01T23:59:59.000Z

242

Low Dose Radiation Research Program: Low-Dose Dose-Response of  

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

Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Dose Rate g-Radiation. Authors: Louise Enns,1 Michael Weinfeld,1 Albert Murtha,1 and Kenneth Bogen2 Institutions: 1Cross Cancer Institute and 2Lawrence Livermore National Laboratory. Clinical and environmental exposure to ionizing radiation rarely exceeds 200 cGy. To examine cell proliferation at early times (up to 5 days) post-irradiation, we are utilizing an assay in which single cells encapsulated within ~30- to 70-µm-diameter agarose gel microdrops (GMDs) are exposed and cultured for 4 days at 37°C, then analyzed by flow cytometry (FC). Clonogenic proliferation is measured as the fraction of occupied GMDs containing multicellular microcolonies after 4 days in culture. This assay was applied to human A549 lung cells exposed to gamma

243

Adaptive hybrid impedance control of robot manipulators: a comparative study  

Science Conference Proceedings (OSTI)

Keywords: direct adaptive control, hybrid impedance control, passivity-based adaptive control, robotics

Lus F. Baptista; Jos M. G. S da Costa

1997-01-01T23:59:59.000Z

244

Radiation dose estimates for radiopharmaceuticals  

SciTech Connect

Tables of radiation dose estimates based on the Cristy-Eckerman adult male phantom are provided for a number of radiopharmaceuticals commonly used in nuclear medicine. Radiation dose estimates are listed for all major source organs, and several other organs of interest. The dose estimates were calculated using the MIRD Technique as implemented in the MIRDOSE3 computer code, developed by the Oak Ridge Institute for Science and Education, Radiation Internal Dose Information Center. In this code, residence times for source organs are used with decay data from the MIRD Radionuclide Data and Decay Schemes to produce estimates of radiation dose to organs of standardized phantoms representing individuals of different ages. The adult male phantom of the Cristy-Eckerman phantom series is different from the MIRD 5, or Reference Man phantom in several aspects, the most important of which is the difference in the masses and absorbed fractions for the active (red) marrow. The absorbed fractions for flow energy photons striking the marrow are also different. Other minor differences exist, but are not likely to significantly affect dose estimates calculated with the two phantoms. Assumptions which support each of the dose estimates appears at the bottom of the table of estimates for a given radiopharmaceutical. In most cases, the model kinetics or organ residence times are explicitly given. The results presented here can easily be extended to include other radiopharmaceuticals or phantoms.

Stabin, M.G.; Stubbs, J.B.; Toohey, R.E. [Oak Ridge Inst. of Science and Education, TN (United States). Radiation Internal Dose Information Center

1996-04-01T23:59:59.000Z

245

Radiation Induced Redox Reactions 1. Anions  

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

Chemerisov, and James F. Wishart J. Phys. Chem. B 115, 3872-3888 (2011). Find paper at ACS Publications Abstract: Room temperature ionic liquids (ILs) find increasing use for...

246

Radiation Induced Fragmentation of Diamide Extraction Agents...  

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

Dale Rimmer, and James F. Wishart J. Phys. Chem. B 116, 2234-2243 (2012). Find paper at ACS Publications or use ACS Articles on Request Abstract: N,N,N',N'-Tetraalkyldiglycolamid...

247

COMPARATIVE ASSESSMENT OF RADIATION-INDUCED GENE  

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

with 0, 50 or 200 cGy gamma-rays and the cells harvested for RNA 48 hours post irradiation. The RNA was hybridized to RAE 230A Affymetrix microarrays and differences in gene...

248

Radiation-induced disruption of skeletal remodeling  

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

of radiation may be exacerbated by other skeletal challenges, such as those posed by aging and physical inactivity. Our central hypothesis is that radiation modulates subsequent...

249

Radiation-induced leiomyosarcoma of the oropharynx  

E-Print Network (OSTI)

2006 Pfeiffer et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License

Jens Pfeiffer; Carsten Christof Boedeker; Gerd Jrgen Ridder; Wolfgang Maier; Gian Kayser

2006-01-01T23:59:59.000Z

250

Mechanisms of radiation-induced gene responses  

Science Conference Proceedings (OSTI)

In the process of identifying genes differentially expressed in cells exposed ultraviolet radiation, we have identified a transcript having a 26-bp region that is highly conserved in a variety of species including Bacillus circulans, yeast, pumpkin, Drosophila, mouse, and man. When the 5` region (flanking region or UTR) of a gene, the sequence is predominantly in +/+ orientation with respect to the coding DNA strand; while in the coding region and the 3` region (UTR), the sequence is most frequently in the +/-orientation with respect to the coding DNA strand. In two genes, the element is split into two parts; however, in most cases, it is found only once but with a minimum of 11 consecutive nucleotides precisely depicting the original sequence. The element is found in a large number of different genes with diverse functions (from human ras p21 to B. circulans chitonase). Gel shift assays demonstrated the presence of a protein in HeLa cell extracts that binds to the sense and antisense single-stranded consensus oligomers, as well as to the double- stranded oligonucleotide. When double-stranded oligomer was used, the size shift demonstrated as additional protein-oligomer complex larger than the one bound to either sense or antisense single-stranded consensus oligomers alone. It is speculated either that this element binds to protein(s) important in maintaining DNA is a single-stranded orientation for transcription or, alternatively that this element is important in the transcription-coupled DNA repair process.

Woloschak, G.E.; Paunesku, T.

1996-10-01T23:59:59.000Z

251

Radiation Induced Redox Reactions 2. Imidazolium Cations  

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

we analyzed stable radiolytic products using 1H and 13C nuclear magnetic resonance (NMR) and tandem electrospray ionization mass spectrometry (ESMS). Our EPR studies reveal...

252

Hanford Environmental Dose Reconstruction Project  

Science Conference Proceedings (OSTI)

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed.

McMakin, A.H.; Cannon, S.D.; Finch, S.M. (comps.)

1992-07-01T23:59:59.000Z

253

Radiation Leukaemogenesis at Low Doses  

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

myeloid leukaemia development at high and low doses. References 1. Cook WD, McCaw BJ, Herring C, John DL, Foote SJ, Nutt SL and Adams JM (2004). PU.1 is a suppressor of myeloid...

254

Adaptation Space: Surviving Non-Maskable Failures  

E-Print Network (OSTI)

Some failures cannot be masked by redundancies, because an unanticipated situation occurred, because fault-tolerance measures were not adequate, or because there was a security breach (which is not amenable to replication). Applications that wish to continue to offer some service despite nonmaskable failure must adapt to the loss of resources. When numerous combinations of non-maskable failure modes are considered, the set of possible adaptations becomes complex. This paper presents adaptation spaces, a formalism for navigating among combinations of adaptations. An adaptation space describes a collection of possible adaptations of a software component or system, and provides a uniform way of viewing a group of alternative software adaptations. Adaptation spaces describe the different means for monitoring the conditions that different adaptations depend on, and the particular configurations through which an adaptive application navigate. Our goal is to use adaptation spaces to provide survivable services to applications despite non-maskable failures such as malicious attacks. We present the basic concepts concerning adaptation spaces, with examples. We then present a formal model for reasoning about and selecting alternative adaptations, allowing developers of survivable application to automate their systems adaptive behavior. 1

Crispin Cowan; Lois Delcambre; Anne-francoise Le Meur; Ling Liu; David Maier; Dylan Mcnamee; Michael Miller; Calton Pu; Perry Wagle; Jonathan Walpole

1998-01-01T23:59:59.000Z

255

Adaptive protection algorithm and system  

Science Conference Proceedings (OSTI)

An adaptive protection algorithm and system for protecting electrical distribution systems traces the flow of power through a distribution system, assigns a value (or rank) to each circuit breaker in the system and then determines the appropriate trip set points based on the assigned rank.

Hedrick, Paul (Pittsburgh, PA); Toms, Helen L. (Irwin, PA); Miller, Roger M. (Mars, PA)

2009-04-28T23:59:59.000Z

256

Adaptive wiener image restoration kernel  

DOE Patents (OSTI)

A method and device for restoration of electro-optical image data using an adaptive Wiener filter begins with constructing imaging system Optical Transfer Function, and the Fourier Transformations of the noise and the image. A spatial representation of the imaged object is restored by spatial convolution of the image using a Wiener restoration kernel.

Yuan, Ding (Henderson, NV)

2007-06-05T23:59:59.000Z

257

The low dose damage response pathways in the mouse mammary glands depends  

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

low dose damage response pathways in the mouse mammary glands depends low dose damage response pathways in the mouse mammary glands depends on genotype, tissue compartment, exposure regimen, and sampling times Joe Gray & Andrew Wyrobek Lawrence Berkeley National Laboratory Abstract The objectives of this research are to characterize the early and persistent low-dose and adaptive response (AR) damage surveillance networks in mammary glands of radiation sensitive and resistant strains of mice to identify the molecular signatures/mechanisms associated with nonlinear modifications of risk for mammary gland cancer. Our approach uses low-dose exposure regimens that have been reported to induce mammary gland cancer in sensitive strains to determine whether low-dose induced pathways are differentially expressed in epithelial or stromal cells and to determine

258

Experimental determination of the radial dose distribution in high gradient regions around {sup 192}Ir wires: Comparison of electron paramagnetic resonance imaging, films, and Monte Carlo simulations  

SciTech Connect

Purpose: The experimental determination of doses at proximal distances from radioactive sources is difficult because of the steepness of the dose gradient. The goal of this study was to determine the relative radial dose distribution for a low dose rate {sup 192}Ir wire source using electron paramagnetic resonance imaging (EPRI) and to compare the results to those obtained using Gafchromic EBT film dosimetry and Monte Carlo (MC) simulations. Methods: Lithium formate and ammonium formate were chosen as the EPR dosimetric materials and were used to form cylindrical phantoms. The dose distribution of the stable radiation-induced free radicals in the lithium formate and ammonium formate phantoms was assessed by EPRI. EBT films were also inserted inside in ammonium formate phantoms for comparison. MC simulation was performed using the MCNP4C2 software code. Results: The radical signal in irradiated ammonium formate is contained in a single narrow EPR line, with an EPR peak-to-peak linewidth narrower than that of lithium formate ({approx}0.64 and 1.4 mT, respectively). The spatial resolution of EPR images was enhanced by a factor of 2.3 using ammonium formate compared to lithium formate because its linewidth is about 0.75 mT narrower than that of lithium formate. The EPRI results were consistent to within 1% with those of Gafchromic EBT films and MC simulations at distances from 1.0 to 2.9 mm. The radial dose values obtained by EPRI were about 4% lower at distances from 2.9 to 4.0 mm than those determined by MC simulation and EBT film dosimetry. Conclusions: Ammonium formate is a suitable material under certain conditions for use in brachytherapy dosimetry using EPRI. In this study, the authors demonstrated that the EPRI technique allows the estimation of the relative radial dose distribution at short distances for a {sup 192}Ir wire source.

Kolbun, N.; Leveque, Ph.; Abboud, F.; Bol, A.; Vynckier, S.; Gallez, B. [Biomedical Magnetic Resonance Unit, Louvain Drug Research Institute, Universite catholique de Louvain, Avenue Mounier 73.40, B-1200 Brussels (Belgium); Molecular Imaging and Experimental Radiotherapy Unit, Institute of Experimental and Clinical Research, Universite catholique de Louvain, Avenue Hippocrate 55, B-1200 Brussels (Belgium); Biomedical Magnetic Resonance Unit, Louvain Drug Research Institute, Universite catholique de Louvain, Avenue Mounier 73.40, B-1200 Brussels (Belgium)

2010-10-15T23:59:59.000Z

259

Induction of Genomic Instability In Vivo by Low Doses of 137Cs gamma rays  

SciTech Connect

The overall goal of this project is to determine if low doses (below or equal to the level traditionally requiring human radiation protection, i.e. less than or equal to 10 cGy) of low LET radiation can induce genomic instability. The magnitude of genomic instability was measured as delayed chromosome instability in bone marrow cells of exposed mice with different levels of endogenous DNA-dependent protein kinase catalytic subunit (DNA-PKcs) activity, i.e. high (C57BL/6J mice), intermediate (BALB/cJ mice), and extremely low (Scid mice). In addition, at early time points (1 and 4 hrs) following irradiation, levels of activation of nuclear factor-kappa B (NF-{kappa}B), a transcription factor known to be involved in regulating the expression of genes responsible for cell protection following stimuli, were measured in these cells. Bone marrow cells were collected at different times following irradiation, i.e. 1 hr, 4 hrs, 1 month, and 6 months. A total of five mice per dose per strain were sacrificed at each time point for sample collection. As a result, a total of 80 mice from each strain were used. The frequency and the type of metaphase chromosome aberrations in bone marrow cells collected from exposed mice at different times following irradiation were used as markers for radiation-induced genomic instability. A three-color fluorescence in situ hybridization (FISH) protocol for mouse chromosomes 1, 2, and 3 was used for the analysis of delayed stable chromosomal aberrations in metaphase cells. All other visible chromatid-type aberrations and gross structural abnormalities involving non-painted chromosomes were also evaluated on the same metaphase cells used for scoring the stable chromosomal aberrations of painted chromosomes. Levels of nuclear factor-kappa B (NF-{kappa}B) activation were also determined in cells at 1 and 4 hrs following irradiation (indicative of early responses).

Rithidech, Kanokporn; Simon, Sanford, R.; Whorton, Elbert, B.

2006-01-06T23:59:59.000Z

260

Low Dose Studies with Focused X-Rays in cell and Tissue Models: Mechanisms of Bystander and Genomic Instability Responses  

SciTech Connect

The management of the risks of exposure of people to ionizing radiation is important in relation to its uses in industry and medicine, also to natural and man-made radiation in the environment. The vase majority of exposures are at a very low level of radiation dose. The risks are of inducing cancer in the exposed individuals and a smaller risk of inducing genetic damage that can be indicate that they are low. As a result, the risks are impossible to detect in population studies with any accuracy above the normal levels of cancer and genetic defects unless the dose levels are high. In practice, this means that our knowledge depends very largely on the information gained from the follow-up of the survivors of the atomic bombs dropped on Japanese cities. The risks calculated from these high-dose short-duration exposures then have to be projected down to the low-dose long-term exposures that apply generally. Recent research using cells in culture has revealed that the relationship between high- and low-dose biological damage may be much more complex than had previously been thought. The aims of this and other projects in the DOE's Low-Dose Program are to gain an understanding of the biological actions of low-dose radiation, ultimately to provide information that will lead to more accurate quantification of low-dose risk. Our project is based on the concept that the processes by which radiation induces cancer start where the individual tracks of radiation impact on cells and tissues. At the dose levels of most low-dose exposures, these events are rare and any individual cells only ''sees'' radiation tracks at intervals averaging from weeks to years apart. This contrasts with the atomic bomb exposures where, on average, each cell was hit by hundreds of tracks instantaneously. We have therefore developed microbeam techniques that enable us to target cells in culture with any numbers of tracks, from one upwards. This approach enables us to study the biological ha sis of the relationship between high- and low-dose exposures. The targeting approach also allows us to study very clearly a newly recognized effect of radiation, the ''bystander effect'', which appears to dominate some low-dose responses and therefore may have a significant role in low-dose risk mechanisms. Our project also addresses the concept that the background of naturally occurring oxidative damage that takes place continually in cells due to byproducts of metabolism may play a role in low-dose radiation risk. This project therefore also examines how cells are damaged by treatments that modify the levels of oxidative damage, either alone or in combination with low-dose irradiation. In this project, we have used human and rodent cell lines and each set of experiments has been carried out on a single cell type. However, low-dose research has to extend into tissues because signaling between cells of different types is likely to influence the responses. Our studies have therefore also included microbeam experiments using a model tissue system that consists of an explant of a small piece of pig ureter grown in culture. The structure of this tissue is similar to that of epithelium and therefore it relates to the tissues in which carcinoma arises. Our studies have been able to measure bystander-induced changes in the cells growing out from the tissue fragment after it has been targeted with a few radiation tracks to mimic a low-dose exposure.

Kathy Held; Kevin Prise; Barry Michael; Melvyn Folkard

2002-12-14T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" from the National Library of EnergyBeta (NLEBeta).
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261

Accumulated Dose in Liver Stereotactic Body Radiotherapy: Positioning, Breathing, and Deformation Effects  

Science Conference Proceedings (OSTI)

Purpose: To investigate the accumulated dose deviations to tumors and normal tissues in liver stereotactic body radiotherapy (SBRT) and investigate their geometric causes. Methods and Materials: Thirty previously treated liver cancer patients were retrospectively evaluated. Stereotactic body radiotherapy was planned on the static exhale CT for 27-60 Gy in 6 fractions, and patients were treated in free-breathing with daily cone-beam CT guidance. Biomechanical model-based deformable image registration accumulated dose over both the planning four-dimensional (4D) CT (predicted breathing dose) and also over each fraction's respiratory-correlated cone-beam CT (accumulated treatment dose). The contribution of different geometric errors to changes between the accumulated and predicted breathing dose were quantified. Results: Twenty-one patients (70%) had accumulated dose deviations relative to the planned static prescription dose >5%, ranging from -15% to 5% in tumors and -42% to 8% in normal tissues. Sixteen patients (53%) still had deviations relative to the 4D CT-predicted dose, which were similar in magnitude. Thirty-two tissues in these 16 patients had deviations >5% relative to the 4D CT-predicted dose, and residual setup errors (n = 17) were most often the largest cause of the deviations, followed by deformations (n = 8) and breathing variations (n = 7). Conclusion: The majority of patients had accumulated dose deviations >5% relative to the static plan. Significant deviations relative to the predicted breathing dose still occurred in more than half the patients, commonly owing to residual setup errors. Accumulated SBRT dose may be warranted to pursue further dose escalation, adaptive SBRT, and aid in correlation with clinical outcomes.

Velec, Michael, E-mail: michael.velec@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, ON (Canada); Institute of Medical Science, University of Toronto, Toronto, ON (Canada); Moseley, Joanne L. [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, ON (Canada); Craig, Tim [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, ON (Canada); Department of Radiation Oncology, University of Toronto, Toronto, ON (Canada); Dawson, Laura A.; Brock, Kristy K. [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, ON (Canada); Department of Radiation Oncology, University of Toronto, Toronto, ON (Canada); Institute of Medical Science, University of Toronto, Toronto, ON (Canada)

2012-07-15T23:59:59.000Z

262

Low Dose Radiation Research Program: Aloke Chatterjee  

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

Chatterjee, A. and Holley, W.R. 1999 Workshop: Biological Effects of Low-Dose and Low-Dose-Rate Radiation Exposures: An Integrated Theoretical and Experimental Approach....

263

Hardware implementation of wireless bit rate adaptation  

E-Print Network (OSTI)

This thesis presents a hardware implementation of the SoftRate bit-rate adaptation protocol. SoftRate is a new bit-rate adaptation protocol, which uses per-bit confidence hints generated by the convolutional decoder to ...

Gross, Samuel A

2010-01-01T23:59:59.000Z

264

An extensible monitoring and adaptation framework  

Science Conference Proceedings (OSTI)

Several techniques have been defined for the monitoring and adaptation of applications. However, such techniques usually work in isolation and cannot be easily integrated to tackle complex monitoring and adaptation scenarios. Furthermore, applications ...

Razvan Popescu; Athanasios Staikopoulos; Siobhn Clarke

2009-11-01T23:59:59.000Z

265

Adaptive control of Unmanned Aerial Systems  

E-Print Network (OSTI)

Adaptive control is considered to be one of the key enabling technologies for future high-performance, safety-critical systems such as air-breathing hypersonic vehicles. Adaptive flight control systems offer improved ...

Dydek, Zachary Thompson

2010-01-01T23:59:59.000Z

266

Boundedness of adaptive nets is decidable  

Science Conference Proceedings (OSTI)

Boundedness is a relevant property for adaptive systems: creation, composition and destruction of components at runtime introduce different infiniteness dimensions. In this paper we show the decidability of the boundedness for adaptive nets, a subclass ... Keywords: Adaptive nets, Boundedness, Decidability, Theory of computation

Olivia Oanea

2011-08-01T23:59:59.000Z

267

Adaptive Techniques for Homebased Software DSMs #  

E-Print Network (OSTI)

Adaptive Techniques for Home­based Software DSMs # Lauro Whately 1 , Raquel Pinto 1 , Muralidharan and evaluates Home­based Adaptive Protocol (HAP), a software distributed shared­memory system. HAP performs two with the adaptive system. Keywords---Software Distributed Shared Memory, Home­basedLazy Release Consistency, Home­based

Bianchini, Ricardo

268

A platform for developing adaptable multicore applications  

Science Conference Proceedings (OSTI)

Computer systems are resource constrained. Application adaptation is a useful way to optimize system resource usage while satisfying the application performance constraints. Previous application adaptation efforts, however, were ad-hoc, time-consuming, ... Keywords: application adaptation, frequency scaling, multicore, parallelization, run-time systems

Dan Fay; Li Shang; Dirk Grunwald

2009-10-01T23:59:59.000Z

269

Presented by Adaptive Hybrid Mesh Refinement for  

E-Print Network (OSTI)

meters. · Orography plays an important role in determining the strength and location of the atmospheric on orographic field data Hybrid adapted geodesic mesh based on orographic field data Structured adapted spherical mesh based on orographic field data #12;7 Khamayseh_ITAPS_SC07 h-Adaptive hybrid mesh generation

270

Enhancing adaptability of distributed groupware applications  

Science Conference Proceedings (OSTI)

Distributed Groupware applications must be designed to cope with an increasingly diverse set of operational conditions. The available network bandwidth and latency, the network connectivity, the number of users, the type of devices, the system load, ... Keywords: adaptability, adaptive, adaptive layer, context awareness, groupware, mobile devices

Tebalo Tsoaeli; Judith Bishop

2005-07-01T23:59:59.000Z

271

Adapted Physical Education Handbook Acknowledgements  

E-Print Network (OSTI)

It would be very difficult to individually acknowledge all the contributors to this handbook. As I visited colleges around the state, I was always welcomed with open arms by the adapted physical education faculty and staff. Their willingness to take time from their very busy schedules to show me their adapted physical education programs, to fill-out and return a six-page survey, and to attend the regional workshops was most appreciated. This handbook would not have been possible without their contributions and daily efforts to improve programs and services for students with disabilities. I would like to acknowledge Scott Hamilton, Statewide DSP&S Coordinator for the California Community Colleges, for his thoughtful support and guidance throughout this project. I would also like to express my thanks to Noel Roberts, Statewide DSP&S Analyst, for her timely administrative assistance in making the handbook possible. I would especially like to acknowledge the professionalism and dedication of the Adapted Physical Education Handbook Project Task Group. The handbook would never have achieved the same impact and magnitude without the knowledge, experience, and expertise that Kathy Bell, Mark Clements, Jon James, Chuck Keller, Mark Lipe, Mary Martin, and Lee Miller Parks brought to this

Jim Haynes

2002-01-01T23:59:59.000Z

272

Low Dose Studies with Focused X-rays in Cell and Tissue Models: Mechanisms of Bystander and Genomic Instability Responses  

SciTech Connect

The management of the risks of exposure of people to ionizing radiation is important in relation to its uses in industry and medicine, also to natural and man-made radiation in the environment. The vase majority of exposures are at a very low level of radiation dose. The risks are of inducing cancer in the exposed individuals and a smaller risk of inducing genetic damage that can be transmitted to children conceived after exposure. Studies of these risks in exposed population studies with any accuracy above the normal levels of cancer and genetic defects unless the dose levels are high. In practice, this means that our knowledge depends very largely on the information gained from the follow-up of the survivors of the atomic bombs dropped on Japanese cities. The risks calculated from these high-dose short-duration exposures then have to be projected down to the low-dose long-term exposures that apply generally. Recent research using cells in culture has revealed that the relations hi between high- and low-dose biological damage may be much more complex than had previously been thought. The aims of this and other projects in the DOE's Low-Dose Program are to gain an understanding of the biological actions of low-dose radiation, ultimately to provide information that will lead to more accurate quantification of low-dose risk. Our project is based on the concept that the processes by which radiation induces cancer start where the individual tracks of radiation impact on cells and tissues. At the dose levels of most low-dose exposures, these events are rare and any individual cells only ''sees'' radiation tracks at intervals averaging from weeks to years apart. This contracts with the atomic bomb exposures where, on average, each cell was hit by hundreds of tracks instantaneously. We have therefore developed microbeam techniques that enable us to target cells in culture with any number of tracks, from one upwards. This approach enables us to study the biological basis of the relationship between high- and low-dose exposures. The targeting approach also allows us to study very clearly a newly recognized effect of radiation, the ''bystander effect'', which appears to dominate some low-dose responses and therefore may have a significant role in low-dose risk mechanisms. Our project also addresses the concept that the background of naturally occurring oxidative damage that takes place continually in cells due to byproducts of metabolism may play a role in treatments that modify the levels of oxidative damage, either alone or in combination with low-dose irradiation. In this project, we have used human and rodent cell lines and each set of experiments has been carried out on a single cell type. However, low-dose research has to extend into tissues because signaling between cells of different types is likely to influence the responses. Our studies have therefore also included microbeam experiments using a model tissue system that consists of an explant of a small piece of pig ureter grown in culture. The structure of this tissue is similar to that of epithelium and there it relates to the tissues in which carcinoma arises. Our studies have been able to measure bystander-induced changes in the cells growing out from the tissue fragment after it has been targeted with a few radiation tracks to mimic a low-dose exposure.

Barry D. Michael; Kathryn Held; Kevin Prise

2002-12-19T23:59:59.000Z

273

Mechanisms of Low-Dose and Adaptive Responses in Radiation Sensitive...  

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

of mice. We have demonstrated that neighboring component cell types within the mammary gland can differ markedly in their molecular responses depending on the genetic background...

274

Adaptive planning using megavoltage fan-beam CT for radiation therapy with testicular shielding  

Science Conference Proceedings (OSTI)

This study highlights the use of adaptive planning to accommodate testicular shielding in helical tomotherapy for malignancies of the proximal thigh. Two cases of young men with large soft tissue sarcomas of the proximal thigh are presented. After multidisciplinary evaluation, preoperative radiation therapy was recommended. Both patients were referred for sperm banking and lead shields were used to minimize testicular dose during radiation therapy. To minimize imaging artifacts, kilovoltage CT (kVCT) treatment planning was conducted without shielding. Generous hypothetical contours were generated on each 'planning scan' to estimate the location of the lead shield and generate a directionally blocked helical tomotherapy plan. To ensure the accuracy of each plan, megavoltage fan-beam CT (MVCT) scans were obtained at the first treatment and adaptive planning was performed to account for lead shield placement. Two important regions of interest in these cases were femurs and femoral heads. During adaptive planning for the first patient, it was observed that the virtual lead shield contour on kVCT planning images was significantly larger than the actual lead shield used for treatment. However, for the second patient, it was noted that the size of the virtual lead shield contoured on the kVCT image was significantly smaller than the actual shield size. Thus, new adaptive plans based on MVCT images were generated and used for treatment. The planning target volume was underdosed up to 2% and had higher maximum doses without adaptive planning. In conclusion, the treatment of the upper thigh, particularly in young men, presents several clinical challenges, including preservation of gonadal function. In such circumstances, adaptive planning using MVCT can ensure accurate dose delivery even in the presence of high-density testicular shields.

Yadav, Poonam [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); School of Advance Sciences, Vellore Institue of Technology University, Vellore, Tamil Nadu (India); Kozak, Kevin [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Tolakanahalli, Ranjini [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Ramasubramanian, V. [School of Advance Sciences, Vellore Institue of Technology University, Vellore, Tamil Nadu (India); Paliwal, Bhudatt R. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin, Riverview Cancer Centre, Wisconsin Rapids, WI (United States); Welsh, James S. [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); Department of Medical Physics, University of Wisconsin, Madison, Madison, WI (United States); Rong, Yi, E-mail: rong@humonc.wisc.edu [Department of Human Oncology, University of Wisconsin, Madison, Madison, WI (United States); University of Wisconsin, Riverview Cancer Centre, Wisconsin Rapids, WI (United States)

2012-07-01T23:59:59.000Z

275

Low Dose Radiation Research Program: Identification of Mouse Genetic  

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

Mouse Genetic Susceptibility to Radiation Carcinogenesis Mouse Genetic Susceptibility to Radiation Carcinogenesis Allan Balmain University of California, San Francisco San Francisco, CA. (Jointly funded by NASA and DOE) Why this Project? To identify pathways that control genetic susceptibility to radiation-induced DNA damage and tumor development using novel developments in genomics together with mouse genetics. Project Goals To identify genetic loci that trigger rapid tumor development of mice after radiation. To characterize new genes at these loci that act as tumor suppressor genes or oncogenes. Experimental Approach New candidate-radiation susceptibility genes will be identified using a unique haplotyping approach. Using DNA from radiation-induced lymphoma, changes in the gene copy number can be detected using BAC microarrays. The

276

Low Dose Radiation Research Program: Howard L. Liber  

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

Howard L. Liber Howard L. Liber Department of Environmental and Radiological Health Sciences Colorado State University Currently Funded Projects Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells Technical Abstracts 2003 Workshop: Delayed genomic instability in human lymphoblasts exposed to 137Cs y-rays radiation Schwartz, J.L., Jordan, R., Lenarczyk, M. and Liber, H.L. 2002 Workshop: Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells. Liber, H.L. and Schwartz, J.L. Publications Zhang, Y., Zhou, J., Held, K.D., Redmond, R.W., Prise, K.M., and Liber, H.L. (2008). Deficiencies of double-strand break repair factors and effects on mutagenesis in directly [gamma]-irradiated and medium-mediated bystander human lymphoblastoid cells. Radiation Research 169(2):197-206.

277

Low Dose Radiation Research Program: Interaction between Tissue and  

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

between Tissue and Cellular Stress Responses: Effect of between Tissue and Cellular Stress Responses: Effect of TGF-ß Depletion on Radiation-Induced p53 Response M.H. Barcellos-Hoff, S.A. Ravani, R.L. Henshall, K.B. Ewan, R.L. Warters,* B. Parvin Lawrence Berkeley National Laboratory *University of Utah One of the most widely studied cellular responses to radiation is the activation of the transcription factor, p53, whose abundance and action dictates individual cellular fate decisions regarding proliferation, differentiation and death. A cell's response to damage needs to be rapid. Thus, it is not surprising that the activation of the p53 stress response primarily involves post-translational changes in the p53 protein. Whereas intracellular radiation-induced mediators of p53 stability have been the subject of intense study, little is known about the extracellular factors

278

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells Howard L. Liber Department of Environmental and Radiological Health Sciences Colorado State University Why This Project This research will be to investigate the condition known as genomic instability. This can be defined as a state in which genetic alterations, including chromosome aberrations and gene mutations, occur at rates that are much higher than normal. In fact, genomic instability is what allows a normal cell to accumulate the multiple genetic alterations that are required to convert it into a cancer cell. The chromosomes of human cells have structures at their ends called telomeres. Telomeres normally function to prevent chromosomes from fusing together end-to-end. An important

279

Adaptive Comfort Model: Simulations & Future Directions  

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

Adaptive Comfort Model: Simulations & Future Directions Adaptive Comfort Model: Simulations & Future Directions Speaker(s): Richard de Dear Date: February 4, 2011 - 12:00pm Location: 90-4133 Seminar Host/Point of Contact: Philip Haves The last 20 years of thermal comfort have witnessed a shift away from the "static" approach (exemplified by the PMV/PPD model) towards the adaptive approach (exemplified by the adaptive models in ASHRAE's Standard 55 (2004, 2010) and the European Union's counterpart standard, EN15251 (2007). - the basis and derivation of the adaptive comfort model - adaptive comfort standards (ASHRAE 55 and EN15251) - new developments and directions (reporting back from the January 2011 ASHRAE Meeting of SSPC-55 in Las Vegas) - environmental variables other than dry bulb, in the adaptive model

280

Low Dose Radiation Research Program: Glossary  

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

Glossary Glossary A B C D E F G H I J K L M N O P Q R S T U V W X Y Z We welcome updates to the glossary. Please send them to Low Dose. A α=β Ratio: A measure of the curvature of the cell survival curve and a measure of the sensitivity of a tissue or tumor to dose fractionation. The dose at which the linear and quadratic components of cell killing are equal. Abscopal Effect: The radiation response in tissue at a distance from the irradiated site invoked by local irradiation. Absorbed Dose Rate: Absorbed dose divided by the time it takes to deliver that dose. High dose rates are usually more damaging to humans and animals than low-dose rates. This is because repair of damage is more efficient when the dose rate is low. Absorbed Dose: The amount of energy deposited in any substance by ionizing

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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.


281

Uncertainty and Sensitivity Analyses Plan. Draft for Peer Review: Hanford Environmental Dose Reconstruction Project  

Science Conference Proceedings (OSTI)

Hanford Environmental Dose Reconstruction (HEDR) Project staff are developing mathematical models to be used to estimate the radiation dose that individuals may have received as a result of emissions since 1944 from the US Department of Energy`s (DOE) Hanford Site near Richland, Washington. An uncertainty and sensitivity analyses plan is essential to understand and interpret the predictions from these mathematical models. This is especially true in the case of the HEDR models where the values of many parameters are unknown. This plan gives a thorough documentation of the uncertainty and hierarchical sensitivity analysis methods recommended for use on all HEDR mathematical models. The documentation includes both technical definitions and examples. In addition, an extensive demonstration of the uncertainty and sensitivity analysis process is provided using actual results from the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC). This demonstration shows how the approaches used in the recommended plan can be adapted for all dose predictions in the HEDR Project.

Simpson, J.C.; Ramsdell, J.V. Jr.

1993-04-01T23:59:59.000Z

282

Uganda-National Adaptation Programme of Action | Open Energy...  

Open Energy Info (EERE)

Adaptation Programme of Action AgencyCompany Organization United Nations Environment Programme, Global Environment Facility, Environmental Alert Topics Adaptation,...

283

Tanzania-National Adaptation Programme of Action | Open Energy...  

Open Energy Info (EERE)

Adaptation Programme of Action AgencyCompany Organization United Nations Environment Programme, Global Environment Facility Topics Adaptation, Background analysis...

284

Radiation dose from cigarette tobacco  

SciTech Connect

The radioactivity in tobacco leaves collected from 15 different regions of Greece before cigarette production was studied in order to estimate the effective dose from cigarette tobacco due to the naturally occurring primordial radionuclides, such as {sup 226}Ra and {sup 210}Pb of the uranium series and {sup 228}Ra of the thorium series and/or man-made produced radionuclides, such as {sup 137}Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the annual effective dose due to inhalation for adults (smokers) for {sup 226}Ra varied from 42.5 to 178.6 {mu}Sv y{sup -1} (average 79.7 {mu}Sv y{sup -1}), while for {sup 228}Ra from 19.3 to 116.0 {mu}Sv y{sup -1} (average 67.1 {mu}Sv y{sup -1}) and for {sup 210}Pb from 47.0 to 134.9 {mu}Sv y{sup -1} (average 104.7 {mu}Sv y{sup -1}), that is the same order of magnitude for each radionuclide. The sum of the effective dose of the three natural radionuclides varied from 151.9 to 401.3 {mu}Sv y{sup -1} (average 251.5 {mu}Sv y{sup -1}). The annual effective dose from {sup 137}Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv y{sup -1} (average 199.3 nSv y{sup -1})

Papastefanou, C. [Aristotle University of Thessaloniki, Atomic and Nuclear Physics Laboratory, Thessaloniki 54124 (Greece)

2008-08-07T23:59:59.000Z

285

NIST: Comparison of Co60 Absorbed Dose for High-Dose ...  

Science Conference Proceedings (OSTI)

... at the dose levels used in radiation processing were ... 1 to 2 parts in 10 2 . The dose-rate effect ... doses for the laboratories that used low-rate gamma ...

2013-03-13T23:59:59.000Z

286

Optimization Online - An adaptive accelerated proximal gradient ...  

E-Print Network (OSTI)

Apr 5, 2013 ... In case the strong convexity parameter is unknown, we also develop an adaptive scheme that can automatically estimate it on the fly, at the cost...

287

Assessing Climate Change Impacts, Vulnerability and Adaptation...  

Open Energy Info (EERE)

The Case of Pantabangan-Carranglan Watershed Jump to: navigation, search Name Assessing Climate Change Impacts, Vulnerability and Adaptation: The Case of Pantabangan-Carranglan...

288

Adaptive computations on conforming quadtree meshes  

E-Print Network (OSTI)

adaptive re?nement for B-spline ?nite element, Int. J.enrichment [6,7] as well as B-splines [8]. These methods

Tabarraei, A; Sukumar, N

2005-01-01T23:59:59.000Z

289

Low Dose Radiation Research Program: Douglas Boreham  

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

Douglas Boreham McMaster University Past Funded Projects The Adaptive Response i p53 Cancer-prone Mice: Loss of Heterozygosity and Chromosome Instability Technical Abstracts 2003...

290

Tailor Made: Adapting Psychotherapeutic Interventions  

E-Print Network (OSTI)

With increased diversity and globalization, there is increased emphasis on awareness of cultural influences on functioning and in fostering cultural competence. This is particularly important in the context of intervention planning and acceptability. The standard approach is through didactic coursework; however the extent to which the content of the courses is universal and includes relevance for intervention is unknown. The purpose of this content analysis was to determine whether or not cultural competence is addressed in psychotherapeutic intervention coursework. Direct intervention syllabi from APA accredited school psychology doctoral programs were analyzed. Findings suggest that cultural competence is minimally addressed in intervention courses. Similarly, the mechanisms for culturally adapting interventions are rarely addressed. Findings further suggest that when addressing cultural competence intervention courses focus on applying knowledge to the delivery of services. Understanding the content of current curricula may provide trainers with information to aid in designing their curriculum so that pre service school psychologists may matriculate with a broader basic therapy skill set.

Henry-Smith, Latanya Sherone

2013-08-01T23:59:59.000Z

291

Downhole tool adapted for telemetry  

DOE Patents (OSTI)

A cycleable downhole tool such as a Jar, a hydraulic hammer, and a shock absorber adapted for telemetry. This invention applies to other tools where the active components of the tool are displaced when the tool is rotationally or translationally cycled. The invention consists of inductive or contact transmission rings that are connected by an extensible conductor. The extensible conductor permits the transmission of the signal before, after, and during the cycling of the tool. The signal may be continuous or intermittent during cycling. The invention also applies to downhole tools that do not cycle, but in operation are under such stress that an extensible conductor is beneficial. The extensible conductor may also consist of an extensible portion and a fixed portion. The extensible conductor also features clamps that maintain the conductor under stresses greater than that seen by the tool, and seals that are capable of protecting against downhole pressure and contamination.

Hall, David R. (Provo, UT); Fox, Joe (Provo, UT)

2010-12-14T23:59:59.000Z

292

A Power and Resolution Adaptive  

E-Print Network (OSTI)

A new power and resolution adaptive flash ADC, named PRA-ADC, is proposed. The PRA-ADC enables exponential power reduction with linear resolution reduction. Unused parallel voltage comparators are switched to standby mode. The voltage comparators consume only the leakage power during the standby mode. The PRA-ADC, capable of operating at 5-bit, 6-bit, 7-bit, and 8-bit precision, dissipates 69 mW at 5-bit and 435 mW at 8-bit. The PRA-ADC was designed and simulated with 0.18 m CMOS technology. The PRA-ADC design is applicable to RF portable communication devices, allowing tighter management of power and e#ciency.

Flash Analog-To-Digital Converter; Jincheol Yoo; Daegyu Lee; Kyusun Choi; Jongsoo Kim

2002-01-01T23:59:59.000Z

293

Biological Basis for Radiation Adaptive Responses that Protect Against Bronchial Epithelial Cell Transformation  

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

Basis for Radiation Adaptive Responses that Protect Against Bronchial Basis for Radiation Adaptive Responses that Protect Against Bronchial Epithelial Cell Transformation Wenshu Chen, Xiuling Xu, Lang Bai, Mabel T. Padilla, Carmen Tellez, Katherine M. Gott, Shuguang Leng, Julie A. Wilder, Steven A. Belinsky, Bobby R. Scott and Yong Lin, Lovelace Respiratory Research Institute, 2425 Ridgecrest Drive SE, Albuquerque, NM 87108 The major hypothesis in this project is that low-dose, low linear-energy-transfer (LET) radiation stimulates an adaptive response that protects cells from neoplastic transformation involving modulation of paracrine factors (e.g., cytokines), cell survival/death signaling pathways, and reprogramming of the epigenome. To test this hypothesis, a validated, sensitive in vitro transformation model and a media transfer

294

Actual Dose Variation of Parotid Glands and Spinal Cord for Nasopharyngeal Cancer Patients During Radiotherapy  

Science Conference Proceedings (OSTI)

Purpose: For intensity-modulated radiotherapy of nasopharyngeal cancer, accurate dose delivery is crucial to the success of treatment. This study aimed to evaluate the significance of daily image-guided patient setup corrections and to quantify the parotid gland volume and dose variations for nasopharyngeal cancer patients using helical tomotherapy megavoltage computed tomography (CT). Methods and Materials: Five nasopharyngeal cancer patients who underwent helical tomotherapy were selected retrospectively. Each patient had received 70 Gy in 35 fractions. Daily megavoltage CT scans were registered with the planning CT images to correct the patient setup errors. Contours of the spinal cord and parotid glands were drawn on the megavoltage CT images at fixed treatment intervals. The actual doses delivered to the critical structures were calculated using the helical tomotherapy Planned Adaptive application. Results: The maximal dose to the spinal cord showed a significant increase and greater variation without daily setup corrections. The significant decrease in the parotid gland volume led to a greater median dose in the later phase of treatment. The average parotid gland volume had decreased from 20.5 to 13.2 cm{sup 3} by the end of treatment. On average, the median dose to the parotid glands was 83 cGy and 145 cGy for the first and the last treatment fractions, respectively. Conclusions: Daily image-guided setup corrections can eliminate significant dose variations to critical structures. Constant monitoring of patient anatomic changes and selective replanning should be used during radiotherapy to avoid critical structure complications.

Han Chunhui [Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA (United States)], E-mail: chan@coh.org; Chen Yijen; Liu An; Schultheiss, Timothy E.; Wong, Jeffrey Y.C. [Division of Radiation Oncology, City of Hope National Medical Center, Duarte, CA (United States)

2008-03-15T23:59:59.000Z

295

Low Dose Radiation Research Program: Image Gallery  

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

Image Gallery Image Gallery These are images, photographs, and charts presented or developed for Low Dose Radiation Research Investigators’ Meetings. They may be used for presentations or reports. To save, right click on the picture, then choose "Save picture as." U.S. annual per-capita effective radiation dose from various sources for 1980. various sources 1980 Enlarge Image. U.S. annual per-capita effective radiation dose from various sources for 2006. various sources 2006 Enlarge Image. U.S. annual per-capita effective radiation dose from man-made sources in the United States for 2006. man-made 2006 Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience (Rem) Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience

296

Transcending the Adaptation/Mitigation Climate Change Science Policy Debate: Unmasking Assumptions about Adaptation and Resilience  

Science Conference Proceedings (OSTI)

The two principal policy approaches to global climate change include mitigation and adaption. In recent years, the interest in adaptation and resilience has increased significantly in part because anthropogenic climate change appears unavoidable ...

Tori L. Jennings

2011-10-01T23:59:59.000Z

297

Hanford Environmental Dose Reconstruction Project. Monthly report  

Science Conference Proceedings (OSTI)

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The independent Technical Steering Panel (TSP) provides technical direction. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates):Source Terms, Environmental Transport, Environmental Monitoring Data, Demography, Food Consumption, and Agriculture, and Environmental Pathways and Dose Estimates.

Cannon, S.D.; Finch, S.M. [comps.

1992-10-01T23:59:59.000Z

298

Hanford Environmental Dose Reconstruction Project. Monthly report  

SciTech Connect

The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates.

Finch, S.M.; McMakin, A.H. [comps.

1992-04-01T23:59:59.000Z

299

Low Dose Ionizing Radiation Modulates Immune Function New Project Overview  

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

Modulates Immune Function New Project Overview Modulates Immune Function New Project Overview Gregory Nelson Loma Linda University Abstract The immune system provides the first line of defense for exposures to environmental hazards. Protective immunity mechanisms using innate or adaptive responses are employed to mitigate acute challenges or amplify the readiness of the system to respond to future challenges. Some stimuli lead to amplified inflammatory reactions such as delayed hypersensitivity which is required for immunity to parasites and can also lead to adverse consequences such as contact dermatitis. Radiation exposure has the potential to aggravate hypersensitivity reactions as well as to suppress protective immunity. Ionizing radiation at high doses has long been recognized as highly effective in destroying cells of the immune system,

300

Low Dose Radiation Research Program: Computational Modeling of Biochemical  

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

Computational Modeling of Biochemical Pathways Linking Ionizing Computational Modeling of Biochemical Pathways Linking Ionizing Radiation to Cell Cycle Arrest, Apoptosis, and Tumor Incidence Authors: Yuchao Maggie Zhao and Rory Conolly Institutions: Center for Computational Systems Biology CIIT Centers for Health Research Long-Range Goal: To develop an integrated, computational framework for the prediction of low-dose-response to ionizing radiation (IR) in people. Methodology: To provide a flexible framework to evaluate mechanisms of cellular adaptive responses after exposure to IR, three progressively more complicated descriptions of biochemical pathways linking DNA damage with cell-cycle checkpoint control and apoptosis were developed. These descriptions focus on p53-dependent checkpoint arrest and apoptosis, p73-dependent apoptosis, and Chk2-dependent checkpoint arrest,

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Adaptive mesh generation for curved domains  

Science Conference Proceedings (OSTI)

This paper considers the technologies needed to support the creation of adaptively constructed meshes for general curved three-dimensional domains and outlines one set of solutions for providing them. A brief review of an effective way to integrate mesh ... Keywords: adaptive meshes, anisotropic meshes, curved meshes

Mark S. Shephard; Joseph E. Flaherty; Kenneth E. Jansen; Xiangrong Li; Xiaojuan Luo; Nicolas Chevaugeon; Jean-Franois Remacle; Mark W. Beall; Robert M. O'Bara

2005-02-01T23:59:59.000Z

302

Adapting Your Home for More Accessible Living  

E-Print Network (OSTI)

It is important for people to live comfortably and independently in their homes. Homes can be adapted to aid people with various disabilities. This publication explains how to make such adaptations for people with vision loss, hearing loss, problems with touch and hand dexterity, loss of strength and range of motion, cognitive difficulties, mobility impairments, and problems with balance and coordination.

Harris, Janie

2007-04-27T23:59:59.000Z

303

Adaptive learning for event modeling and characterization  

Science Conference Proceedings (OSTI)

Adaptive learning of specific patterns or events of interest has been an area of significant research for various applications in the last two decades. In developing diagnostic evaluation and safety monitoring applications of a propulsion system, it ... Keywords: Adaptive learning, Event modeling, Fuzzy k-means clustering, Hierarchical clustering

Shuangshuang Dai; Atam P. Dhawan

2007-05-01T23:59:59.000Z

304

Adaptive workflow nets for grid computing  

Science Conference Proceedings (OSTI)

Existing grid applications commonly use workflows for the orchestration of grid services. Existing workflow models however suffer from the lack of adaptivity. In this paper we define Adaptive Grid Workflow nets (AGWF nets) appropriate for modeling grid ... Keywords: coordination, grid computing, modeling, petri nets, verification, workflows

Carmen Bratosin; Kees van Hee; Natalia Sidorova

2007-09-01T23:59:59.000Z

305

Applying Adaptive Evolutionary Algorithms to Hard Problems  

E-Print Network (OSTI)

Applying Adaptive Evolutionary Algorithms to Hard Problems J.I. van Hemert1 jvhemert into two distinct parts. The main theme is adaptive evolutionary algorithms. The rst part covers. The second part mainly consists of the development of a library. Its use is aimed at evolutionary algorithms

Emmerich, Michael

306

DRM protected dynamic adaptive HTTP streaming  

Science Conference Proceedings (OSTI)

Dynamic adaptive HTTP streaming (DASH) is a new concept for video streaming using consecutive downloads of short video segments. 3GPP has developed the basic DASH standard which is further extended by the Open IPTV Forum (OIPF) and MPEG. In all versions ... Keywords: adaptive http streaming, content protection, digital rights management, encryption

Frank Hartung; Sinan Kesici; Daniel Catrein

2011-02-01T23:59:59.000Z

307

Optimal Adaptive Waveform Selection for Target Tracking  

E-Print Network (OSTI)

Optimal Adaptive Waveform Selection for Target Tracking Barbara La Scala Mohammad Rezaeian Bill algorithms. This paper describes an optimal adaptive waveform selection algorithm for target tracking. An adap- tive scheduling algorithm that selects the waveforms to be used in future epochs based on current

Rezaeian, Mohammad-Jafar

308

Adaptive sampling for Bayesian variable selection  

E-Print Network (OSTI)

Adaptive sampling for Bayesian variable selection DAVID J. NOTT Department of Statistics for variable selection and for dealing with model un- certainty have become increasingly popular in recent consider adaptive Markov chain Monte Carlo schemes for Bayesian variable selection in Gaussian linear

Blennerhassett, Peter

309

Adaptive Fuzzy PID Control for Boiler Deaerator  

Science Conference Proceedings (OSTI)

The boiler deaerator temperature control system is a non-linear, time-varying, delay control process. It can not achieve satisfying effect using traditional control algorithm to control deaerator water temperature, the paper proposes an adaptive fuzzy ... Keywords: Deaerator, Adaptive, Fuzzy control, PID control

Lei Jinli

2012-08-01T23:59:59.000Z

310

Assessing systems adaptability to a product family  

Science Conference Proceedings (OSTI)

In many cases, product families are established on top of a successful pilot product. While this approach provides an option to measure many concrete attributes like performance and memory footprint, adequateness and adaptability of the architecture ... Keywords: adaptability, assessment, product line architecture, software product lines

Mika Korhonen; Tommi Mikkonen

2004-07-01T23:59:59.000Z

311

Dose rate visualization of radioisotope thermoelectric generators  

DOE Green Energy (OSTI)

Advanced visualization techniques can be used to investigate gamma ray and neutron dose rates around complex dose rate intensive operations. A method has been developed where thousands of dose points are calculated using the MCNP(Monte Carlo N-Particle) computer code and then displayed to create color contour plots of the dose rate for complex geometries. Once these contour plots are created, they are sequenced together creating an animation to dynamically show how the dose rate changes with changes in the geometry or source over time.

Schwarz, R.A.; Kessler, S.F.; Tomaszewski, T.A.

1995-09-01T23:59:59.000Z

312

Petascale Adaptive Computational Fluid Dynamics | Argonne Leadership  

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

Petascale Adaptive Computational Fluid Dynamics Petascale Adaptive Computational Fluid Dynamics PI Name: Kenneth Jansen PI Email: jansen@rpi.edu Institution: Rensselaer Polytechnic Institute The specific aim of this request for resources is to examine scalability and robustness of our code on BG/P. We have confirmed that, during the flow solve phase, our CFD flow solver does exhibit perfect strong scaling to the full 32k cores on our local machine (CCNI-BG/L at RPI) but this will be our first access to BG/P. We are also eager to study the performance of the adaptive phase of our code. Some aspects have scaled well on BG/L (e.g., refinement has produced adaptive meshes that take a 17 million element mesh and perform local adaptivity on 16k cores to match a requested size field to produce a mesh exceeding 1 billion elements) but other aspects (e.g.,

313

Feedback based adaptive compensation of control system sensor uncertainties  

Science Conference Proceedings (OSTI)

In this paper, the problem of adaptively compensating sensor uncertainties is addressed in a feedback based framework. In this study, sensor characteristics are modeled as parametrizable uncertain functions and a compensator is constructed to adaptively ... Keywords: Adaptive control, Adaptive systems, Sensor and data fusion, Tracking and adaptation

Shanshan Li; Gang Tao

2009-02-01T23:59:59.000Z

314

Low dose radiation and cancer in A-bomb survivors: latency and non-linear dose-response in the 195090 mortality cohort  

E-Print Network (OSTI)

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Analyses of Japanese A-bomb survivors ' cancer mortality risks are used to establish recommended annual dose limits, currently set at 1 mSv (public) and 20 mSv (occupational). Do radiation doses below 20 mSv have significant impact on cancer mortality in Japanese A-bomb survivors, and is the dose-response linear? Methods: I analyse stomach, liver, lung, colon, uterus, and all-solid cancer mortality in the 0 20 mSv colon dose subcohort of the 195090 (grouped) mortality cohort, by Poisson regression using a time-lagged colon dose to detect latency, while controlling for gender, attained age, and age-atexposure. I compare linear and non-linear models, including one adapted from the cellular bystander effect for ? particles. Results: With a lagged linear model, Excess Relative Risk (ERR) for the liver and all-solid cancers is significantly positive and several orders of magnitude above extrapolations from the Life Span Study Report 12 analysis of the full cohort. Non-linear models are strongly superior to the linear model for the stomach (latency 11.89 years), liver (36.90), lung (13.60) and all-solid (43.86) in fitting

Greg Dropkin; Greg Dropkin

2007-01-01T23:59:59.000Z

315

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

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

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.

316

Dose-to-Man Program progress report, FY 1973  

SciTech Connect

The Dose-to-Man Program at the Savannah River Plant (SRP) was conceived in FY-1972 and operations began in FY-1973. The major objectives of the program are to develop (or adapt), test, and apply comprehensive mathematical models to calculate the radiation dose-to-man from one or more point sources released to the atmosphere or surface waters. These models will be applied to SRP operations; however, the methods are expected to be generally applicable over a large portion of the southeastern United States. A discussion is included of a new meteorological data acquisition program now in operation using a 1200-ft TVtower located near the plant site and seven 200-ft towers to be located onsite in FY-1974. Previously collected meteorological data from the TV-tower were analyzed to show spatial and temporal variation in eddy diffusivity, mesoscale kinetic energy spectra, and dispersion climatology based upon wind-sequencing information. A discussion of a framework for calculation of doseto-man, and a comparison of the Brookhaven National Laboratory (BNL) and Pasquill methods for determining dispersion coefficients are also included. A currert sulfur dioxide survey is discussed which will help verify the calculation techniques for predicting dispersion from heated plumes. (auth)

Crawford, T.V.

1974-01-01T23:59:59.000Z

317

NIST Ionizing Radiation Division 1999 - Current Directions  

Science Conference Proceedings (OSTI)

... effect relationships for radiation-induced stochastic ... validate the EPR dose assessment methods ... Calibration of Low-Energy Photon Brachytherapy ...

318

A Model of Adaptation in Collaborative Multi-Agent Systems  

Science Conference Proceedings (OSTI)

Adaptation is an essential requirement for autonomous agent systems functioning in uncertain dynamic environments. Adaptation allows agents to change their behavior in order to improve the overall sys tem performance. We describe a general mechanism ... Keywords: adaptation, mathematical models, robotics

Kristina Lerman

2004-09-01T23:59:59.000Z

319

Adaptive simulation of gas turbine performance  

SciTech Connect

A method is presented allowing the simulation of gas turbine performance with the possibility of adapting to engine particularities. Measurements along the gas path are used, in order to adapt a given performance model by appropriate modification of the component maps. The proposed method can provide accurate simulation for engines of the same type, differing due to manufacturing or assembly tolerances. It doesn't require accurate component maps, as they are derived during the adaptation process. It also can be used for health monitoring purposes, introducing thus a novel approach for component condition assessment. The effectiveness of the proposed method is demonstrated by application to an industrial gas turbine.

Stamatis, A.; Mathioudakis, K.; Papailiou, K.D. (Ethnikon Metsovion Polytechneion, Athens (Greece))

1990-04-01T23:59:59.000Z

320

Simulation of dose reduction in tomosynthesis  

Science Conference Proceedings (OSTI)

Purpose: Methods for simulating dose reduction are valuable tools in the work of optimizing radiographic examinations. Using such methods, clinical images can be simulated to have been collected at other, lower, dose levels without the need of additional patient exposure. A recent technology introduced to healthcare that needs optimization is tomosynthesis, where a number of low-dose projection images collected at different angles is used to reconstruct section images of an imaged object. The aim of the present work was to develop a method of simulating dose reduction for digital radiographic systems, suitable for tomosynthesis. Methods: The developed method uses information about the noise power spectrum (NPS) at the original dose level and the simulated dose level to create a noise image that is added to the original image to produce an image that has the same noise properties as an image actually collected at the simulated dose level. As the detective quantum efficiency (DQE) of digital detectors operating at the low dose levels used for tomosynthesis may show a strong dependency on the dose level, it is important that a method for simulating dose reduction for tomosynthesis takes this dependency into account. By applying an experimentally determined relationship between pixel mean and pixel variance, variations in both dose and DQE in relevant dose ranges are taken into account. Results: The developed method was tested on a chest tomosynthesis system and was shown to produce NPS of simulated dose-reduced projection images that agreed well with the NPS of images actually collected at the simulated dose level. The simulated dose reduction method was also applied to tomosynthesis examinations of an anthropomorphic chest phantom, and the obtained noise in the reconstructed section images was very similar to that of an examination actually performed at the simulated dose level. Conclusions: In conclusion, the present article describes a method for simulating dose reduction suitable for tomosynthesis. However, the method applies equally well to any digital radiographic system, although the benefits of correcting for DQE variations may be smaller.

Svalkvist, Angelica; Baath, Magnus [Department of Radiation Physics, University of Gothenburg, SE-413 45 Gothenburg (Sweden) and Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, SE-413 45 Gothenburg (Sweden)

2010-01-15T23:59:59.000Z

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321

Low Dose Radiation Research Program: Interaction of Genome and Cellular  

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

of Genome and Cellular Micronenvioronment of Genome and Cellular Micronenvioronment Mina Bissell Life Sciences Division Lawrence Berkeley National Laboratory Why this Project While normal stoma can delay or prevent tumorigenesis, abnormal stromal components can promote tumor growth. Acquired or inherited mutations that alter stromal cell function can release the context-suppressed malignant cells. Literature spanning more than a century has shown that inflammation associated with tissue wounding can produce tunors. Radiation produces changes in reactive oxygen that are similar to inflammation and may represent a mechanism for radiation-induced damage. Project Goals To determine the underlying role of stromal alterations in controling genomic instability accompanying epithelial-mesenchyumal transformation.

322

Adaptive/Nonadaptive Proton Radiation Planning and Outcomes in a Phase II Trial for Locally Advanced Non-small Cell Lung Cancer  

SciTech Connect

Purpose: To analyze dosimetric variables and outcomes after adaptive replanning of radiation therapy during concurrent high-dose protons and chemotherapy for locally advanced non-small cell lung cancer (NSCLC). Methods and Materials: Nine of 44 patients with stage III NSCLC in a prospective phase II trial of concurrent paclitaxel/carboplatin with proton radiation [74 Gy(RBE) in 37 fractions] had modifications to their original treatment plans after re-evaluation revealed changes that would compromise coverage of the target volume or violate dose constraints; plans for the other 35 patients were not changed. We compared patients with adaptive plans with those with nonadaptive plans in terms of dosimetry and outcomes. Results: At a median follow-up of 21.2 months (median overall survival, 29.6 months), no differences were found in local, regional, or distant failure or overall survival between groups. Adaptive planning was used more often for large tumors that shrank to a greater extent (median, 107.1 cm{sup 3} adaptive and 86.4 cm{sup 3} nonadaptive; median changes in volume, 25.3% adaptive and 1.2% nonadaptive; P<.01). The median number of fractions delivered using adaptive planning was 13 (range, 4-22). Adaptive planning generally improved sparing of the esophagus (median absolute decrease in V{sub 70}, 1.8%; range, 0%-22.9%) and spinal cord (median absolute change in maximum dose, 3.7 Gy; range, 0-13.8 Gy). Without adaptive replanning, target coverage would have been compromised in 2 cases (57% and 82% coverage without adaptation vs 100% for both with adaptation); neither patient experienced local failure. Radiation-related grade 3 toxicity rates were similar between groups. Conclusions: Adaptive planning can reduce normal tissue doses and prevent target misses, particularly for patients with large tumors that shrink substantially during therapy. Adaptive plans seem to have acceptable toxicity and achieve similar local, regional, and distant control and overall survival, even in patients with larger tumors, vs nonadaptive plans.

Koay, Eugene J.; Lege, David [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mohan, Radhe [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Komaki, Ritsuko; Cox, James D. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Chang, Joe Y., E-mail: jychang@mdanderson.org [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

2012-12-01T23:59:59.000Z

323

Dose estimates of alternative plutonium pyrochemical processes.  

Science Conference Proceedings (OSTI)

We have coupled our dose calculation tool Pandemonium with a discrete-event, object-oriented, process-modeling system ProMosO to analyze a set of alternatives for plutonium purification operations. The results follow expected trends and indicate, from a dose perspective, that an experimental flowsheet may warrant further research to see if it can be scaled to industrial levels. Flowsheets that include fluoride processes resulted in the largest doses.

Kornreich, D. E. (Drew E.); Jackson, J. W. (Joseph W.); Boerigter, S. T. (Stephen T.); Averill, W. A. (William A.); Fasel, J. H. (Joseph H.)

2002-01-01T23:59:59.000Z

324

The Cost to Developing Countries of Adapting to Climate Change...  

Open Energy Info (EERE)

The Cost to Developing Countries of Adapting to Climate Change Jump to: navigation, search Tool Summary Name: The Cost to Developing Countries of Adapting to Climate Change Agency...

325

India-Vulnerability Assessment and Enhancing Adaptive Capacities...  

Open Energy Info (EERE)

Vulnerability Assessment and Enhancing Adaptive Capacities to Climate Change Jump to: navigation, search Name India-Vulnerability Assessment and Enhancing Adaptive Capacities to...

326

Climate Change Adaptation: Weighing Strategies for Heat-Related...  

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

Climate Change Adaptation: Weighing Strategies for Heat-Related Health Challenges Print E-mail Climate Change Adaptation: Weighing Strategies for Heat-Related Health Challenges...

327

Ethiopia-Climate Change National Adaptation Programme of Action...  

Open Energy Info (EERE)

Adaptation Programme of Action Jump to: navigation, search Name Ethiopia-Climate Change National Adaptation Programme of Action AgencyCompany Organization United Nations...

328

Rwanda-National Adaptation Programs of Action to Climate Change...  

Open Energy Info (EERE)

Rwanda-National Adaptation Programs of Action to Climate Change Jump to: navigation, search Name Rwanda-National Adaptation Programs of Action to Climate Change AgencyCompany...

329

Burundi-National Adaptation Plan of Action to Climate Change...  

Open Energy Info (EERE)

Burundi-National Adaptation Plan of Action to Climate Change Jump to: navigation, search Name Burundi-National Adaptation Plan of Action to Climate Change AgencyCompany...

330

Using Technology to Bring Climate Change Adaptation Research...  

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

Using Technology to Bring Climate Change Adaptation Research to the Great Lakes Print E-mail Using Technology to Bring Climate Change Adaptation Research to the Great Lakes...

331

Adaptation to Climate Variability and Change: A Guidance Manual...  

Open Energy Info (EERE)

Adaptation to Climate Variability and Change: A Guidance Manual for Development Planning Jump to: navigation, search Tool Summary Name: Adaptation to Climate Variability and...

332

Practical Method of Adaptive Radiotherapy for Prostate Cancer Using Real-Time Electromagnetic Tracking  

SciTech Connect

Purpose: We have created an automated process using real-time tracking data to evaluate the adequacy of planning target volume (PTV) margins in prostate cancer, allowing a process of adaptive radiotherapy with minimal physician workload. We present an analysis of PTV adequacy and a proposed adaptive process. Methods and Materials: Tracking data were analyzed for 15 patients who underwent step-and-shoot multi-leaf collimation (SMLC) intensity-modulated radiation therapy (IMRT) with uniform 5-mm PTV margins for prostate cancer using the Calypso Registered-Sign Localization System. Additional plans were generated with 0- and 3-mm margins. A custom software application using the planned dose distribution and structure location from computed tomography (CT) simulation was developed to evaluate the dosimetric impact to the target due to motion. The dose delivered to the prostate was calculated for the initial three, five, and 10 fractions, and for the entire treatment. Treatment was accepted as adequate if the minimum delivered prostate dose (D{sub min}) was at least 98% of the planned D{sub min}. Results: For 0-, 3-, and 5-mm PTV margins, adequate treatment was obtained in 3 of 15, 12 of 15, and 15 of 15 patients, and the delivered D{sub min} ranged from 78% to 99%, 96% to 100%, and 99% to 100% of the planned D{sub min}. Changes in D{sub min} did not correlate with magnitude of prostate motion. Treatment adequacy during the first 10 fractions predicted sufficient dose delivery for the entire treatment for all patients and margins. Conclusions: Our adaptive process successfully used real-time tracking data to predict the need for PTV modifications, without the added burden of physician contouring and image analysis. Our methods are applicable to other uses of real-time tracking, including hypofractionated treatment.

Olsen, Jeffrey R.; Noel, Camille E.; Baker, Kenneth; Santanam, Lakshmi; Michalski, Jeff M. [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States); Parikh, Parag J., E-mail: pparikh@radonc.wustl.edu [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO (United States)

2012-04-01T23:59:59.000Z

333

Cross-layer wireless bit rate adaptation  

E-Print Network (OSTI)

This paper presents SoftRate, a wireless bit rate adaptation protocol that is responsive to rapidly varying channel conditions. Unlike previous work that uses either frame receptions or signal-to-noise ratio (SNR) estimates ...

Vutukuru, Mythili

2009-01-01T23:59:59.000Z

334

Cross-Layer Wireless Bit Rate Adaptation  

E-Print Network (OSTI)

This paper presents SoftRate, a wireless bit rate adaptation protocol that is responsive to rapidly varying channel conditions. Unlike previous work that uses either frame receptions or signal-to-noise ratio (SNR) estimates ...

Vutukuru, Mythili

335

EVALUATING CONSERVATION EFFECTIVENESS AND ADAPTATION IN  

E-Print Network (OSTI)

EVALUATING CONSERVATION EFFECTIVENESS AND ADAPTATION IN DYNAMIC LANDSCAPES ADENA R. RISSMAN* I INTRODUCTION Despite the widespread use of conservation easements, their conservation outcomes are relatively unknown.1 Evaluating conservation easement effectiveness requires interdisciplinary research that reaches

Rissman, Adena

336

Robust adaptive subspace extraction for DOA tracking  

Science Conference Proceedings (OSTI)

This paper addresses the problem of extracting a time-varying signal subspace from noisy signal measurements for direction-of-arrival (DOA) estimation and tracking. A robust adaptive method for extracting the signal subspace is developed based on robust ...

Dekun Yang; S. J. Flockton

1996-05-01T23:59:59.000Z

337

Adaptive file transfers for diverse environments  

Science Conference Proceedings (OSTI)

This paper presents dsync, a file transfer system that can dynamically adapt to a wide variety of environments. While many transfer systems work well in their specialized ontext, their performance comes at the cost of generality, and they perform poorly ...

Himabindu Pucha; Michael Kaminsky; David G. Andersen; Michael A. Kozuch

2008-06-01T23:59:59.000Z

338

Information Resources: Adaptive Street Lighting Controls  

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

Adaptive Street Lighting Controls Adaptive Street Lighting Controls This two-part DOE Municipal Solid-State Street Lighting Consortium webinar focused on LED street lighting equipped with adaptive control components. In Part I, presenters Amy Olay of the City of San Jose, CA, and Kelly Cunningham of the California Lighting Technology Center at UC Davis discussed their experiences as early adopters of these smart street lighting systems. In Part II, presenters Laura Stuchinsky of the City of San Jose, CA, and Michael Poplawski of Pacific Northwest National Laboratory explored the MSSLC's recently released Model Specification for Adaptive Control and Remote Monitoring of LED Roadway Luminaires. Part I: Experiences and Benefits June 11, 2013 View the presentation slides Part II: Reviewing the MSSLC's Model Specification

339

Exponential convergence with adaptive Monte Carlo  

Science Conference Proceedings (OSTI)

For over a decade, it has been known that exponential convergence on discrete transport problems was possible using adaptive Monte Carlo techniques. Now, exponential convergence has been empirically demonstrated on a spatially continuous problem.

Booth, T.E.

1997-11-01T23:59:59.000Z

340

Usability engineering for the adaptive web  

Science Conference Proceedings (OSTI)

This chapter discusses a usability engineering approach for the design and the evaluation of adaptive web-based systems, focusing on practical issues. A list of methods will be presented, considering a user-centered approach. After having introduced ...

Cristina Gena; Stephan Weibelzahl

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Adaptive control of a generic hypersonic vehicle  

E-Print Network (OSTI)

This thesis presents a an adaptive augmented, gain-scheduled baseline LQR-PI controller applied to the Road Runner six-degree-of-freedom generic hypersonic vehicle model. Uncertainty in control effectiveness, longitudinal ...

Wiese, Daniel Philip

2013-01-01T23:59:59.000Z

342

High Performance Adaptive Distributed Scheduling Algorithm  

Science Conference Proceedings (OSTI)

Exascale computing requires complex runtime systems that need to consider affinity, load balancing and low time and message complexity for scheduling massive scale parallel computations. Simultaneous consideration of these objectives makes online distributed ... Keywords: Distributed Scheduling, Adaptive Scheduling, Performance Analysis

Ankur Narang, Abhinav Srivastava, R. K. Shyamasundar

2013-05-01T23:59:59.000Z

343

Adaptive power management in energy harvesting systems  

Science Conference Proceedings (OSTI)

Recently, there has been a substantial interest in the design of systems that receive their energy from regenerative sources such as solar cells. In contrast to approaches that attempt to minimize the power consumption we are concerned with adapting ...

Clemens Moser; Lothar Thiele; Davide Brunelli; Luca Benini

2007-04-01T23:59:59.000Z

344

Providing Dynamic Instructional Adaptation in Programming Learning  

Science Conference Proceedings (OSTI)

This paper describes an approach to create an Intelligent Tutoring System that provides dynamic personalization and learning activities sequencing adaptation by combining eLearning standards and Artificial Intelligent techniques. The work takes advantage ...

Francisco Jurado; Olga C. Santos; Miguel A. Redondo; Jess G. Boticario; Manuel Ortega

2008-09-01T23:59:59.000Z

345

Convert! : the adaptive reuse of churches  

E-Print Network (OSTI)

This thesis examines the phenomenon of vacated churches and analyzes the major issues underlying their adaptive reuse in order to help promulgate an awareness of the range of successful strategies and solutions that are ...

Kiley, Christopher John, 1972-

2004-01-01T23:59:59.000Z

346

Model 467-1 Adapter Hardware Manual  

E-Print Network (OSTI)

-1 Adapter vi Important Notes: Make sure you follow proper ESD handling procedures (refer to EIA-625, ESD ............................................................................. 15 1.10 Interrupt And Error Handling....................................................... 16 1 Jumpers.........................................................32 3.4.6 Remote RAM Jumpers

Berns, Hans-Gerd

347

Adaptive learning of semantic locations and routes  

Science Conference Proceedings (OSTI)

Adaptation of devices and applications based on contextual information has a great potential to enhance usability and mitigate the increasing complexity of mobile devices. An important topic in context-aware computing is to learn semantic locations and ...

Keshu Zhang; Haifeng Li; Kari Torkkola; Mike Gardner

2007-09-01T23:59:59.000Z

348

Adaptive learning of semantic locations and routes  

Science Conference Proceedings (OSTI)

Adaptation of devices and applications based on contextual information has a great potential to enhance usability and mitigate the increasing complexity of mobile devices. An important topic in context-aware computing is to learn semantic locations and ...

Keshu Zhang; Haifeng Li; Kari Torkkola; Mike Gardner

2007-10-01T23:59:59.000Z

349

Dynamic Grid Adaptation Using the MPDATA Scheme  

Science Conference Proceedings (OSTI)

A dynamic grid adaptation (DGA) scheme is developed using various combinations of the multidimensional positive definite advection transport algorithm (MPDATA) to show the applicability of DGA with the MPDATA scheme to solve advection problems. A ...

John P. Iselin; Joseph M. Prusa; William J. Gutowski

2002-04-01T23:59:59.000Z

350

Statistical Design for Adaptive Weather Observations  

Science Conference Proceedings (OSTI)

Suppose that one has the freedom to adapt the observational network by choosing the times and locations of observations. Which choices would yield the best analysis of the atmospheric state or the best subsequent forecast? Here, this problem of ...

L. Mark Berliner; Zhan-Qian Lu; Chris Snyder

1999-08-01T23:59:59.000Z

351

Low Dose Radiation Research Program: Transgenerational Effects...  

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

Transgenerational Effects of Chronic Low-Dose Irradiation in a Medaka Fish Model System Colorado State University Why this Project? There are major gaps in our knowledge about...

352

Low Dose Radiation Research Program: Research Highlights  

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

energy, are the surrounding unirradiated cells also at an increased risk of cancer? Latest Research, Response to Fukushima, Integrating Low Dose into Policy-All Featured at...

353

ORISE: Radiation Dose Estimates and Other Compendia  

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

article addresses methods that can be used to rapidly estimate internal and external radiation dose magnitudes that can be used to help guide early medical management. Included...

354

Low Dose Radiation Program: Selected Websites  

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

The views expressed in these links do not necessarily reflect the view of the Low Dose Radiation Research Program. Scientific Links Agencies with Radiation Regulatory...

355

Low Dose Radiation Research Program: Katherine Vallis  

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

Margaret Hospital Newly Funded Project The Characterization of Genetic Responses to Low Dose Radiation Using a Genome-Wide Insertional Mutagensis Approach Technical Abstracts 2005...

356

Low Dose Radiation Research Program: Mohan Natarajan  

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

of Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Funded Project Real-Time Molecular Study of Bystander Effect Using...

357

Low Dose Radiation Research Program: Multidimensional Analysis...  

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

Multidimensional Analysis of Human Epithelial Cell Response to Low Dose Radiation Mary Helen Barcellos-Hoff Lawrence Berkeley National Laboratory Berkeley, CA. (Jointly funded by...

358

Adaptive Urban Dispersion Integrated Model  

DOE Green Energy (OSTI)

Numerical simulations represent a unique predictive tool for understanding the three-dimensional flow fields and associated concentration distributions from contaminant releases in complex urban settings (Britter and Hanna 2003). Utilization of the most accurate urban models, based on fully three-dimensional computational fluid dynamics (CFD) that solve the Navier-Stokes equations with incorporated turbulence models, presents many challenges. We address two in this work; first, a fast but accurate way to incorporate the complex urban terrain, buildings, and other structures to enforce proper boundary conditions in the flow solution; second, ways to achieve a level of computational efficiency that allows the models to be run in an automated fashion such that they may be used for emergency response and event reconstruction applications. We have developed a new integrated urban dispersion modeling capability based on FEM3MP (Gresho and Chan 1998, Chan and Stevens 2000), a CFD model from Lawrence Livermore National Lab. The integrated capability incorporates fast embedded boundary mesh generation for geometrically complex problems and full three-dimensional Cartesian adaptive mesh refinement (AMR). Parallel AMR and embedded boundary gridding support are provided through the SAMRAI library (Wissink et al. 2001, Hornung and Kohn 2002). Embedded boundary mesh generation has been demonstrated to be an automatic, fast, and efficient approach for problem setup. It has been used for a variety of geometrically complex applications, including urban applications (Pullen et al. 2005). The key technology we introduce in this work is the application of AMR, which allows the application of high-resolution modeling to certain important features, such as individual buildings and high-resolution terrain (including important vegetative and land-use features). It also allows the urban scale model to be readily interfaced with coarser resolution meso or regional scale models. This talk will discuss details of the approach and present results for some example calculations performed in Manhattan in support of the DHS Urban Dispersion Program (UDP) using some of the tools developed as part of this new capability.

Wissink, A; Chand, K; Kosovic, B; Chan, S; Berger, M; Chow, F K

2005-11-03T23:59:59.000Z

359

Adaptive nonparametric regression on spin fiber bundles  

Science Conference Proceedings (OSTI)

The construction of adaptive nonparametric procedures by means of wavelet thresholding techniques is now a classical topic in modern mathematical statistics. In this paper, we extend this framework to the analysis of nonparametric regression on sections ... Keywords: 42B35, 42C10, 42C40, 46E35, 62G08, 62G20, Adaptive nonparametric regression, Mixed spin needlets, Spin Besov spaces, Spin fiber bundles, Thresholding

Claudio Durastanti; Daryl Geller; Domenico Marinucci

2012-02-01T23:59:59.000Z

360

X-band EPR imaging as a tool for gradient dose reconstruction in irradiated bones  

SciTech Connect

Purpose: Various tools are currently available for dose reconstruction in individuals after accidental exposure to ionizing radiation. Among the available biological analyses, Monte Carlo simulations, and biophysical methods, such as electron paramagnetic resonance (EPR), the latter has proved its usefulness for retrospective dosimetry. Although EPR spectroscopy is probably the most sensitive technique, it does not provide spatial dosimetric data. This information is, however, highly desirable when steep dose gradient irradiations are involved. The purpose of this work was to explore the possibilities of EPR imaging (EPRI) for spatial dose reconstruction in irradiated biological material. Methods: X-band EPRI was used to reconstruct ex vivo the relative dose distribution in human bone samples and hydroxyapatite phantoms after irradiation with brachytherapy seeds or x rays. Three situations were investigated: Homogeneous, stepwise gradient, and continuous gradient irradiation. Results: EPRI gave a faithful relative spin density distribution in bone samples and in hydroxyapatite phantoms. Measured dose ratios were in close agreement with the actual delivered dose ratios. EPRI was able to distinguish the dose gradients induced by two different sources ({sup 125}I and {sup 192}Ir). However, the measured spatial resolution of the system was 1.9 mm and this appeared to be a limiting factor. The method could be improved by using new signal postprocessing strategies. Conclusions: This study demonstrates that EPRI can be used to assess the regional relative dose distribution in irradiated bone samples. The method is currently applicable to ex vivo measurements of small size samples with low variation in tissue density but is likely to be adapted for in vivo application using L-band EPRI.

Leveque, Philippe; Godechal, Quentin; Bol, Anne; Trompier, Francois; Gallez, Bernard [Biomedical Magnetic Resonance Unit, Universite catholique de Louvain, B-1200 Brussels (Belgium); Molecular Imaging and Experimental Radiotherapy Unit, Universite catholique de Louvain, B-1200 Brussels (Belgium); Institut de Surete Nucleaire et de Radioprotection, F-92262 Fontenay-aux-Roses (France); Biomedical Magnetic Resonance Unit, Universite catholique de Louvain, B-1200 Brussels (Belgium)

2009-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Forecasting the Dose and Dose Rate from a Solar Particle Event Using Localized Weighted Regression  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

T. F. Nichols; L. W. Townsend; J. W. Hines

362

An updated dose assessment for Rongelap Island  

Science Conference Proceedings (OSTI)

We have updated the radiological dose assessment for Rongelap Island at Rongelap Atoll using data generated from field trips to the atoll during 1986 through 1993. The data base used for this dose assessment is ten fold greater than that available for the 1982 assessment. Details of each data base are presented along with details about the methods used to calculate the dose from each exposure pathway. The doses are calculated for a resettlement date of January 1, 1995. The maximum annual effective dose is 0.26 mSv y{sup {minus}1} (26 mrem y{sup {minus}1}). The estimated 30-, 50-, and 70-y integral effective doses are 0.0059 Sv (0.59 rem), 0.0082 Sv (0.82 rem), and 0.0097 Sv (0.97 rem), respectively. More than 95% of these estimated doses are due to 137-Cesium ({sup 137}Cs). About 1.5% of the estimated dose is contributed by 90-Strontium ({sup 90}Sr), and about the same amount each by 239+240-Plutonium ({sup 239+240}PU), and 241-Americium ({sup 241}Am).

Robison, W.L.; Conrado, C.L.; Bogen, K.T.

1994-07-01T23:59:59.000Z

363

Low Dose Radiation Research Program: About  

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

About About Background. Extensive research on the health effects of radiation using standard epidemiological and toxicological approaches has been done for decades to characterize responses of populations and individuals to high radiation doses, and to set exposure standards to protect both the public and the workforce. These standards were set using models that extrapolated from the cancers observed following exposure to high doses of radiation to predicted, but not measurable, changes in cancer frequency at low radiation doses. The use of models was necessary because of our inability to detect changes in cancer incidence following low doses of radiation. Historically, the predominant approach has been the Linear-no-Threshold model (see Wikipedia entry) and collective dose concept that assumes each unit of radiation, no

364

Low Dose Radiation Research Program: National Laboratories  

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

National Laboratories National Laboratories The Low Dose Radiation Program funding encompasses several Scientific Focus Areas (SFAs). The SFAs fund merit-reviewed research at DOE national laboratories. This management approach was created in 2008 by the Office of Biological and Environmental Research (BER) within the U.S. Department of Energy's (DOE's) Office of Science. PNNL's Low Dose Radiation Research Program Scientific Focus Area Linear and Nonlinear Tissue-Signaling Mechanisms in Response to Low Dose and Low Dose-Rate Radiation This program is funded as a U.S. Department of Energy Scientific Focus Area (SFA), and is an integrated cooperative program to understand low dose radiation effects in a complex model system. Coordinating Multidisciplinary Expertise The SFAs are designed to take advantage of the multidisciplinary,

365

Dose calculations using MARS for Bremsstrahlung beam stops and collimators in APS beamline stations.  

Science Conference Proceedings (OSTI)

The Monte Carlo radiation transport code MARS is used to model the generation of gas bremsstrahlung (GB) radiation from 7-GeV electrons which scatter from residual gas atoms in undulator straight sections within the Advanced Photon Source (APS) storage ring. Additionally, MARS is employed to model the interactions of the GB radiation with components along the x-ray beamlines and then determine the expected radiation dose-rates that result. In this manner, MARS can be used to assess the adequacy of existing shielding or the specifications for new shielding when required. The GB radiation generated in the 'thin-target' of an ID straight section will consist only of photons in a 1/E-distribution up to the full energy of the stored electron beam. Using this analytical model, the predicted GB power for a typical APS 15.38-m insertion device (ID) straight section is 4.59 x 10{sup -7} W/nTorr/mA, assuming a background gas composed of air (Z{sub eff} = 7.31) at room temperature (293K). The total GB power provides a useful benchmark for comparisons between analytical and numerical approaches. We find good agreement between MARS and analytical estimates for total GB power. The extended straight section 'target' creates a radial profile of GB, which is highly peaked centered on the electron beam. The GB distribution reflects the size of the electron beam that creates the radiation. Optimizing the performance of MARS in terms of CPU time per incident trajectory requires the use of a relatively short, high-density gas target (air); in this report, the target density is {rho}L = 2.89 x 10{sup -2} g/cm{sup 2} over a length of 24 cm. MARS results are compared with the contact dose levels reported in TB-20, which used EGS4 for radiation transport simulations. Maximum dose-rates in 1 cc of tissue phantom form the initial basis for comparison. MARS and EGS4 results are approximately the same for maximum 1-cc dose-rates and attenuation in the photon-dominated regions; for thicker targets, however, the dose-rate no longer depends only on photon attenuation, as photoneutrons (PNs) begin to dominate. The GB radiation-induced photoneutron measurements from four different metals (Fe, Cu, W, and Pb) are compared with MARS predictions. The simulated dose-rates for beamline 6-ID are approximately 3-5 times larger than the measured values, whereas those for beamline 11-ID are much closer. Given the uncertainty in local values of pressure and Z, the degree of agreement between MARS and the PN measurements is good. MARS simulations of GB-induced radiation in and around the FOE show the importance of using actual pressure and gas composition (Z{sub eff}) to obtain accurate PN dose. For a beam current of 300 mA, extrapolating pressure data measured in previously published studies predicts an average background gas pressure of 27 nTorr. An average atomic number of Z{sub eff} = 4.0 is obtained from the same studies. In addition, models of copper masks presently in use at the APS are included. Simulations show that inclusion of exit masks make significant differences in both the radiation spatial distribution within the FOE, as well as the peak intensity. Two studies have been conducted with MARS to assess shielding requirements. First, dose levels in contact with the outside wall of the FOE are examined when GB radiation strikes Pb or W beam stops of varying transverse size within the FOE. Four separate phantom regions are utilized to measure the dose, two at beam elevation and two at the horizontal beam position. The first two phantoms are used for scoring FOE dose along the outside and back walls, horizontally; the second two collect dose on the roof and vertically on the back wall. In all cases, the beam stop depth is maintained at 30 cm. Inclusion of front end (FE) exit masks typically cause a 1-2 order-of-magnitude increase in the dose-rates relative to the case with no masks. Masks place secondary bremsstrahlung sources inside the FOE, and therefore they must be shielded appropriately. The MARS model does not fully account for all shielding present

Dooling, J.; Accelerator Systems Division (APS)

2010-11-01T23:59:59.000Z

366

The effect of measurement error on the dose-response curve  

Science Conference Proceedings (OSTI)

In epidemiological studies for an environmental risk assessment, doses are often observed with errors. However, they have received little attention in data analysis. This paper studies the effect of measurement errors on the observed dose-response curve. Under the assumptions of the monotone likelihood ratio on errors and a monotone increasing dose-response curve, it is verified that the slope of the observed dose-response curve is likely to be gentler than the true one. The observed variance of responses are not so homogeneous as to be expected under models without errors. The estimation of parameters in a hockey-stick type dose-response curve with a threshold is considered on line of the maximum likelihood method for a functional relationship model. Numerical examples adaptable to the data in a 1986 study of the effect of air pollution that was conducted in Japan are also presented. The proposed model is proved to be suitable to the data in the example cited in this paper.

Yoshimura, I. (Nagoya Univ. (Japan))

1990-07-01T23:59:59.000Z

367

Brief An adaptive PID learning control of robot manipulators  

Science Conference Proceedings (OSTI)

An adaptive PID learning controller which consists of an adaptive PID feedback control scheme and a feedforward input learning scheme is proposed for learning of periodic robot motion. In the learning controller, the adaptive PID feedback controller ... Keywords: Adaptive PID learning, Learning rules, Robot motion control

Tae-Yong Kuc; Woong-Gie Han

2000-05-01T23:59:59.000Z

368

UNDP-Adaptation Learning Mechanism | Open Energy Information  

Open Energy Info (EERE)

Adaptation Learning Mechanism Adaptation Learning Mechanism Jump to: navigation, search Logo: UNDP-Adaptation Learning Mechanism Name UNDP-Adaptation Learning Mechanism Agency/Company /Organization United Nations Development Programme Sector Climate, Energy, Land, Water Topics Adaptation Resource Type Lessons learned/best practices, Training materials Website http://www.adaptationlearning. Program Start 2007 References Adaptation Learning Mechanism[1] Abstract Seeking to provide stakeholders with a common platform for sharing and learning, the ALM bridges knowledge gaps by bringing relevant knowledge and stakeholders together to exchange information, experiences, and expertise. Additionally, the ALM complements the wide range of adaptation knowledge networks and initiatives already underway.

369

An architecture for adaptive intrusion-tolerant applications: Experiences with Auto-adaptive and Reconfigurable Systems  

Science Conference Proceedings (OSTI)

Applications that are part of a mission-critical information system need to maintain a usable level of key services through ongoing cyber-attacks. In addition to the well-publicized denial of service (DoS) attacks, these networked and distributed applications ... Keywords: Byzantine fault tolerance, adaptive defense, adaptive middleware, intrusion tolerance, redundancy, survivability architecture

Partha Pal; Paul Rubel; Michael Atighetchi; Franklin Webber; William H. Sanders; Mouna Seri; HariGovind Ramasamy; James Lyons; Tod Courtney; Adnan Agbaria; Michel Cukier; Jeanna Gossett; Idit Keidar

2006-09-01T23:59:59.000Z

370

Evaluation of a personalized digital library based on cognitive styles: Adaptivity vs. adaptability  

Science Conference Proceedings (OSTI)

Personalization can be addressed by adaptability and adaptivity, which have different advantages and disadvantages. This study investigates how digital library (DL) users react to these two techniques. More specifically, we develop a personalized DL ... Keywords: Cognitive styles, Digital libraries, Individual differences, Personalization

Enrique Frias-Martinez; Sherry Y. Chen; Xiaohui Liu

2009-02-01T23:59:59.000Z

371

Adaptation of user views to business requirements: towards adaptive views models  

Science Conference Proceedings (OSTI)

This article describes an approach to model user views in service-oriented groupware systems in order to support the adaptation of views in collaborative projects environments. The issue is to adapt the visualization to the users' business requirements ... Keywords: AEC (architecture engineering construction), CSCW, information visualization, model driven engineering, user view, user view model

Conrad Boton; Sylvain Kubicki; Gilles Halin

2010-09-01T23:59:59.000Z

372

Solid-State Lighting: Adaptive Street Lighting Controls  

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

Adaptive Street Lighting Adaptive Street Lighting Controls to someone by E-mail Share Solid-State Lighting: Adaptive Street Lighting Controls on Facebook Tweet about Solid-State Lighting: Adaptive Street Lighting Controls on Twitter Bookmark Solid-State Lighting: Adaptive Street Lighting Controls on Google Bookmark Solid-State Lighting: Adaptive Street Lighting Controls on Delicious Rank Solid-State Lighting: Adaptive Street Lighting Controls on Digg Find More places to share Solid-State Lighting: Adaptive Street Lighting Controls on AddThis.com... Conferences & Meetings Presentations Publications Webcasts Videos Tools Adaptive Street Lighting Controls This two-part DOE Municipal Solid-State Street Lighting Consortium webinar focused on LED street lighting equipped with adaptive control components.

373

Petascale, Adaptive CFD | Argonne Leadership Computing Facility  

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

Petascale, Adaptive CFD Petascale, Adaptive CFD Petascale, Adaptive CFD PI Name: Kenneth Jansen PI Email: jansenke@colorado.edu Institution: U. Colorado-Boulder Allocation Program: ESP Allocation Hours at ALCF: 150 Million Year: 2010 to 2013 Research Domain: Engineering The aerodynamic simulations proposed will involve modeling of active flow control based on synthetic jet actuation that has been shown experimentally to produce large-scale flow changes (e.g., re-attachment of separated flow or virtual aerodynamic shaping of lifting surfaces) from micro-scale input (e.g., a 0.1 W piezoelectric disk resonating in a cavity alternately pushes/pulls out/in the fluid through a small slit to create small-scale vortical structures that interact with, and thereby dramatically alter, the cross flow). This is a process that has yet to be understood fundamentally.

374

AdaptiveARC | Open Energy Information  

Open Energy Info (EERE)

AdaptiveARC AdaptiveARC Jump to: navigation, search Name AdaptiveARC Address 7683 Sitio Manana Place Carlsbad, California Zip 92009 Sector Biomass Product Waste-to-clean-energy startup is developing an arc-plasma reactor Website http://www.adaptivearc.com/ Coordinates 33.07959°, -117.22539° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":33.07959,"lon":-117.22539,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

375

Load attenuating passively adaptive wind turbine blade  

DOE Patents (OSTI)

A method and apparatus for improving wind turbine performance by alleviating loads and controlling the rotor. The invention employs the use of a passively adaptive blade that senses the wind velocity or rotational speed, and accordingly modifies its aerodynamic configuration. The invention exploits the load mitigation prospects of a blade that twists toward feather as it bends. The invention includes passively adaptive wind turbine rotors or blades with currently preferred power control features. The apparatus is a composite fiber horizontal axis wind-turbine blade, in which a substantial majority of fibers in the blade skin are inclined at angles of between 15 and 30 degrees to the axis of the blade, to produces passive adaptive aeroelastic tailoring (bend-twist coupling) to alleviate loading without unduly jeopardizing performance.

Veers, Paul S. (Albuquerque, NM); Lobitz, Donald W. (Albuquerque, NM)

2003-01-01T23:59:59.000Z

376

Fast adaptive elliptical filtering using box splines  

E-Print Network (OSTI)

We demonstrate that it is possible to filter an image with an elliptic window of varying size, elongation and orientation with a fixed computational cost per pixel. Our method involves the application of a suitable global pre-integrator followed by a pointwise-adaptive localization mesh. We present the basic theory for the 1D case using a B-spline formalism and then appropriately extend it to 2D using radially-uniform box splines. The size and ellipticity of these radially-uniform box splines is adaptively controlled. Moreover, they converge to Gaussians as the order increases. Finally, we present a fast and practical directional filtering algorithm that has the capability of adapting to the local image features.

Chaudhury, Kunal Narayan; Unser, Michael

2009-01-01T23:59:59.000Z

377

Radiological Dose Calculations for Fusion Facilities  

Science Conference Proceedings (OSTI)

This report summarizes the results and rationale for radiological dose calculations for the maximally exposed individual during fusion accident conditions. Early doses per unit activity (Sieverts per TeraBecquerel) are given for 535 magnetic fusion isotopes of interest for several release scenarios. These data can be used for accident assessment calculations to determine if the accident consequences exceed Nuclear Regulatory Commission and Department of Energy evaluation guides. A generalized yearly dose estimate for routine releases, based on 1 Terabecquerel unit releases per radionuclide, has also been performed using averaged site parameters and assumed populations. These routine release data are useful for assessing designs against US Environmental Protection Agency yearly release limits.

Michael L. Abbott; Lee C. Cadwallader; David A. Petti

2003-04-01T23:59:59.000Z

378

Four-dimensional dose distributions of step-and-shoot IMRT delivered with real-time tumor tracking for patients with irregular breathing: Constant dose rate vs dose rate regulation  

SciTech Connect

Purpose: Dose-rate-regulated tracking (DRRT) is a tumor tracking strategy that programs the MLC to track the tumor under regular breathing and adapts to breathing irregularities during delivery using dose rate regulation. Constant-dose-rate tracking (CDRT) is a strategy that dynamically repositions the beam to account for intrafractional 3D target motion according to real-time information of target location obtained from an independent position monitoring system. The purpose of this study is to illustrate the differences in the effectiveness and delivery accuracy between these two tracking methods in the presence of breathing irregularities. Methods: Step-and-shoot IMRT plans optimized at a reference phase were extended to remaining phases to generate 10-phased 4D-IMRT plans using segment aperture morphing (SAM) algorithm, where both tumor displacement and deformation were considered. A SAM-based 4D plan has been demonstrated to provide better plan quality than plans not considering target deformation. However, delivering such a plan requires preprogramming of the MLC aperture sequence. Deliveries of the 4D plans using DRRT and CDRT tracking approaches were simulated assuming the breathing period is either shorter or longer than the planning day, for 4 IMRT cases: two lung and two pancreatic cases with maximum GTV centroid motion greater than 1 cm were selected. In DRRT, dose rate was regulated to speed up or slow down delivery as needed such that each planned segment is delivered at the planned breathing phase. In CDRT, MLC is separately controlled to follow the tumor motion, but dose rate was kept constant. In addition to breathing period change, effect of breathing amplitude variation on target and critical tissue dose distribution is also evaluated. Results: Delivery of preprogrammed 4D plans by the CDRT method resulted in an average of 5% increase in target dose and noticeable increase in organs at risk (OAR) dose when patient breathing is either 10% faster or slower than the planning day. In contrast, DRRT method showed less than 1% reduction in target dose and no noticeable change in OAR dose under the same breathing period irregularities. When {+-}20% variation of target motion amplitude was present as breathing irregularity, the two delivery methods show compatible plan quality if the dose distribution of CDRT delivery is renormalized. Conclusions: Delivery of 4D-IMRT treatment plans, stemmed from 3D step-and-shoot IMRT and preprogrammed using SAM algorithm, is simulated for two dynamic MLC-based real-time tumor tracking strategies: with and without dose-rate regulation. Comparison of cumulative dose distribution indicates that the preprogrammed 4D plan is more accurately and efficiently conformed using the DRRT strategy, as it compensates the interplay between patient breathing irregularity and tracking delivery without compromising the segment-weight modulation.

Yang Xiaocheng; Han-Oh, Sarah; Gui Minzhi; Niu Ying; Yu, Cedric X.; Yi Byongyong [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States); Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21231 (United States); Medical Physics Division, Saint Agnes Cancer Center, Baltimore, Maryland 21229 (United States); Department of Physics, George Washington University, Washington, DC 20052 (United States); Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, Maryland 21201 (United States)

2012-09-15T23:59:59.000Z

379

A SINGLE-PARAMETER ADAPTIVE COMB FILTER  

E-Print Network (OSTI)

The study is concerned with a single-parameter adaptive comb filter (ACF), a multi-notch filter with periodically located nulls. The filter is suggested to retrieve a waveform modeled by superposition of harmonics, in particular, periodic non-sinusoidal signal. Using trigonometric constraints between the signal fundamental frequency and over tones results in a non-linear estimation problem. In the present study, the parameter adjustment relies on the extended Kalman filter scheme. Particularly, the 2, 3 and 4 notch ACF are derived and tested under different conditions. Given a multi-tone scenario, the ACF significantly outperforms common adaptive multi-notch filter.

Single-Parameter Adaptive Comb; Naum G. Chernoguz

2001-01-01T23:59:59.000Z

380

Hanford Environmental Dose Reconstruction Project monthly report  

Science Conference Proceedings (OSTI)

The objective of the Hanford Environmental Dose Reconstruction MDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in envirorunental pathways. epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering. radiation dosimetry. and cultural anthropology. Included are appointed members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source Terms; Environmental Transport; Environmental Monitoring Data Demography, Food Consumption, and Agriculture; and Environmental Pathways and Dose Estimates.

McMakin, A.H., Cannon, S.D.; Finch, S.M. [comps.

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Hanford Environmental Dose Reconstruction Project. Monthly report  

Science Conference Proceedings (OSTI)

The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at Hanford since 1944. The TSP consists of experts in environmental pathways, epidemiology, surface-water transport, ground-water transport, statistics, demography, agriculture, meteorology, nuclear engineering, radiation dosimetry, and cultural anthropology. Included are appointed technical members representing the states of Oregon, Washington, and Idaho, a representative of Native American tribes, and an individual representing the public. The project is divided into the following technical tasks. These tasks correspond to the path radionuclides followed from release to impact on humans (dose estimates): Source terms, environmental transport, environmental monitoring data, demography, food consumption, and agriculture, and environmental pathways and dose estimates. Progress is discussed.

McMakin, A.H.; Cannon, S.D.; Finch, S.M. [comps.

1992-07-01T23:59:59.000Z

382

Low Dose Radiation Research Program: Michael Weil  

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

Dubrova, Y., Weil, M., and Brenner, D. H2AX Foci after Low Dose-Rate Irradiation Reveal a Defect in DNA DSB Processing in Cells from Unaffected Parents of...

383

Low Dose Radiation Research Program: Mina Bissell  

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

Abstracts 2006 Workshop: 3D Tissue Models for the Study of the Effects of Low-Dose Irradiation Nelson, C.M., Fata, J E., Kenny, P.A., and Bissell, M.J. Publications Kumari, I.,...

384

Low Dose Radiation Research Program: David Nelson  

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

L.E., Nelson, D., Sorensen, K., Tucker, J.D., and Wyrobek, A.J. (2005). Low-dose irradiation alters the transcript profiles of human lymphoblasoid cells, including genes...

385

Low Dose Radiation Research Program: Thomas Weber  

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

2005 Workshop: A Paracrine Signal Mediates The Cell Transformation Response To Low Dose Gamma Radiation in JB6 Cells. Weber, T.J., Siegel, R.W., Markillie, L.M., Chrisler,...

386

Low Dose Radiation Research Program: Molecular Characterization...  

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

the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing Radiation Chaun-Yuan Li Duke University Medical Center Durham, NC Why this Project? To evaluate the roles...

387

Low Dose Radiation Research Program: Micronutrient Deficiency...  

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

DNA damage is appreciable and increases with age,3;4 Our aim is to compare low dose radiation with micronutrient deficiency, and endogenous damage by a variety of measures...

388

A National Strategy for Adaptation to Climate Change | Open Energy  

Open Energy Info (EERE)

A National Strategy for Adaptation to Climate Change A National Strategy for Adaptation to Climate Change Jump to: navigation, search Tool Summary Name: A National Strategy for Adaptation to Climate Change Agency/Company /Organization: Coalition for Rainforest Nations Topics: Adaptation, Pathways analysis Resource Type: Guide/manual Website: www.rainforestcoalition.org/eng/ References: A National Strategy for Adaptation to Climate Change[1] Logo: A National Strategy for Adaptation to Climate Change Click here to view document A National Strategy for Adaptation to Climate Change References ↑ "A National Strategy for Adaptation to Climate Change" Retrieved from "http://en.openei.org/w/index.php?title=A_National_Strategy_for_Adaptation_to_Climate_Change&oldid=382940" Category: Tools

389

Adaptable methodology for automation application development  

Science Conference Proceedings (OSTI)

An adaptable methodology for automation application development (AMAAD) is introduced. This development methodology is based on the key concept that design automation (DA) applications are a subset of higher level knowledge-based engineering (KBE) applications, ... Keywords: CommonKADS, Design automation, Knowledge-based engineering, MOKA, Productivity enhancement

Christian van der Velden; Cees Bil; Xinghuo Xu

2012-04-01T23:59:59.000Z

390

Adaptive Battery Charge Scheduling with Bursty Workloads  

E-Print Network (OSTI)

1 Adaptive Battery Charge Scheduling with Bursty Workloads Dylan Lexie , Shan Lin, and Jie Wu.wu@temple.edu Abstract--Battery-powered wireless sensor devices need to be charged to provide the desired functionality after deployment. Task or even device failures can occur if the voltage of the battery is low

Wu, Jie

391

EMMA: an adaptive display for virtual therapy  

Science Conference Proceedings (OSTI)

Environments used up to now for therapeutic applications are invariable ones. Their contents can not be changed neither by the therapist nor by the patient. However, this is a technical issue that can be solved with current technology. In this paper, ... Keywords: adaptive display, virtual reality, virtual therapy

Mariano Alcaiz; Cristina Botella; Beatriz Rey; Rosa Baos; Jose A. Lozano; Nuria Lasso de la Vega; Diana Castilla; Javier Montesa; Antonio Hospitaler

2007-07-01T23:59:59.000Z

392

Modling and implementing adaptative pedagogical hyper documents  

Science Conference Proceedings (OSTI)

Today, a large number of interactive systems are developed thanks to hypermedia documents particularly in the education field. Due to the lack of experience feedback, it is always necessary to carry out reflections on the architecture of these systems ... Keywords: HCI, XML, adaptative hypermedia, e-learning

Sofiane Benadi; Patrick Prvot; Jean-Yves Ramel

2003-11-01T23:59:59.000Z

393

Efficient adaptive meshing of parametric models  

Science Conference Proceedings (OSTI)

Parametric modeling is becoming the representation of choice for most modern solid modelers. However, when generating the finite-element mesh of the model for simulation and analysis, most meshing tools ignore the parametric information and use only ... Keywords: adaptivity, mesh generation, parametric models

Alla Sheffer; Alper ngr

2001-05-01T23:59:59.000Z

394

A framework for adaptive execution in grids  

Science Conference Proceedings (OSTI)

Grids offer a dramatic increase in the number of available processing and storing resources that can be delivered to applications. However, efficient job submission and management continue being far from accessible to ordinary scientists and engineers ... Keywords: Globus, adaptive execution, grid technology, job migration

Eduardo Huedo; Ruben S. Montero; Ignacio M. Llorente

2004-06-01T23:59:59.000Z

395

Adaptive context reasoning in pervasive systems  

Science Conference Proceedings (OSTI)

It is hard to believe that the internet is now in its adolescent stage. Our information age is replete with communication capable, intelligent, sensor equipped devices. Social networks, web services, and global information repositories make a wealth ... Keywords: context, context inference, context middleware adaptation, context quality, context reasoning, information quality, quality aggregation, quality propagation

Bridget Beamon; Mohan Kumar

2010-11-01T23:59:59.000Z

396

Robust adaptive beamforming via target tracking  

Science Conference Proceedings (OSTI)

The proposed robust beamformer adaptively self-corrects and tracks desired-source location errors or variations regardless of the eigenstructure of the input correlation matrix, of the array shape and nature of the noise. It only requires an order of ...

S. Gazor; S. Affes; Y. Grenier

1996-06-01T23:59:59.000Z

397

STAPL: standard template adaptive parallel library  

Science Conference Proceedings (OSTI)

The Standard Template Adaptive Parallel Library (stapl) is a high-productivity parallel programming framework that extends C++ and stl with unified support for shared and distributed memory parallelism. stapl provides distributed data structures (pContainers) ... Keywords: high productivity parallel programming, library, parallel data structures

Antal Buss; Harshvardhan; Ioannis Papadopoulos; Olga Pearce; Timmie Smith; Gabriel Tanase; Nathan Thomas; Xiabing Xu; Mauro Bianco; Nancy M. Amato; Lawrence Rauchwerger

2010-05-01T23:59:59.000Z

398

Compact upwind schemes on adaptive octrees  

Science Conference Proceedings (OSTI)

Compact high-order upwind schemes using reconstruction from cell-averages are derived for application with the compressible three-dimensional Navier-Stokes equations. An adaptive-octree mesh, combined with the Adams-Bashforth-Moulton family of predictor-corrector ... Keywords: Finite-volume, High-order, Navier-Stokes, Predictor-corrector

Scott M. Murman

2010-02-01T23:59:59.000Z

399

Origin of Mutations Under Selection: The Adaptive  

E-Print Network (OSTI)

Origin of Mutations Under Selection: The Adaptive Mutation Controversy John R. Roth,1 Elisabeth 2006 by Annual Reviews. All rights reserved 0066-4227/06/1013-0477$20.00 Key Words natural selection Growth under selection causes new genotypes to predominate in a population. It is difficult to determine

California at Davis, University of

400

Dynamic repartitioning of adaptively refined meshes  

Science Conference Proceedings (OSTI)

One ingredient which is viewed as vital to the successful conduct of many large-scale numerical simulations is the ability to dynamically repartition the underlying adaptive finite element mesh among the processors so that the computations are balanced ... Keywords: multilevel diffusion, multilevel graph repartitioning, scratch-remap, wavefront diffusion

Kirk Schloegel; George Karypis; Vipin Kumar

1998-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose radiation-induced adaptive" 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

Query weighting for ranking model adaptation  

Science Conference Proceedings (OSTI)

We propose to directly measure the importance of queries in the source domain to the target domain where no rank labels of documents are available, which is referred to as query weighting. Query weighting is a key step in ranking model adaptation. As ...

Peng Cai; Wei Gao; Aoying Zhou; Kam-Fai Wong

2011-06-01T23:59:59.000Z

402

Passive solar energy: climate-adaptive architecture  

DOE Green Energy (OSTI)

Passive solar, climate adaptive architecture uses the following concepts: conservation, sun angles, glass, and thermal mass (passive heating and cooling). Specific measures of these concepts are briefly discussed. Passive solar water heating systems discussed are breadbox and thermosyphon water heaters. (MCW)

Baccei, B.

1981-09-01T23:59:59.000Z

403

An ATM Adaptation Layer for Reliable Transfers  

Science Conference Proceedings (OSTI)

There has been much attention given to ATM Adaptation Layers (AAL) over the ten-year history of ATM standardization. Yet none of the existing standards include a retransmission protocol to ensure reliability of the transfers. In this paper we propose ...

Gunnar Karlsson

1996-09-01T23:59:59.000Z

404

Hybrid algorithms for adaptive array systems  

Science Conference Proceedings (OSTI)

In recent years, mobile communications have caused an explosive growth to the number of wireless users. This growth has triggered an enormous demand not only for capacity but also for better coverage and quality of services with priority on interference ... Keywords: adaptive arrays, beamforming, least mean squares algorithm, mobile communications, sample matrix inversion algorithm, smart antennas

D. Papadimitriou; I. O. Vardiambasis

2005-03-01T23:59:59.000Z

405

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

SciTech Connect

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

Not Available

1988-07-01T23:59:59.000Z

406

A Dynamically Adapting Weather and Dispersion Model: The Operational Multiscale Environment Model with Grid Adaptivity (OMEGA)  

Science Conference Proceedings (OSTI)

The Operational Multiscale Environment Model with Grid Adaptivity (OMEGA) and its embedded Atmospheric Dispersion Model is a new atmospheric simulation system for real-time hazard prediction, conceived out of a need to advance the state of the ...

David P. Bacon; Nashat N. Ahmad; Zafer Boybeyi; Thomas J. Dunn; Mary S. Hall; Pius C. S. Lee; R. Ananthakrishna Sarma; Mark D. Turner; Kenneth T. Waight III; Steve H. Young; John W. Zack

2000-07-01T23:59:59.000Z

407

Low Dose Radiation Research Program: Kenneth T. Bogen  

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

T. Bogen Lawrence Livermore National Laboratory Technical Abstracts 2002 Workshop: Low-dose dose-response of proliferating human cells exposed to low dose rate g-radiation. Enns,...

408

Agriculture-related radiation dose calculations  

SciTech Connect

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

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

1987-10-01T23:59:59.000Z

409

Low Dose Radiation Research Program: The Progeny of Irradiated Mammary  

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

Progeny of Irradiated Mammary Epithelial Cells Exhibit a Phenotype Progeny of Irradiated Mammary Epithelial Cells Exhibit a Phenotype Characteristic of Malignancy Mary H. Barcellos-Hoff, R.L. Henshall-Powell, M.J. Bissell, and B. Parvin Lawrence Berkeley National Laboratory, Life Sciences Division We have proposed that the ability of radiation to induce altered microenvironments affects the frequency and features of neoplastic progression. Thus, we have sought to characterize the irradiated microenvironment and determine how these events contribute to mammary carcinogenesis. By using imaging bioinformatics to analyze mouse and human models of breast cancer we have now examined cell adhesion molecules (CAMs) critical for tissue-specific organization and function. We found that 1) radiation-induced microenvironments can contribute to neoplastic potential

410

Low Dose Radiation Research Program: David J. Chen  

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

2003 Workshop: Gene Expression Profile of Normal Human Fibroblast After Ionizing Irradiation, a comparison study between low dose and high dose. Chen, D.J. 2002 Workshop:...

411

Development of a Low Dose Rate Irradiation Facility for Long...  

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

Low Dose Rate Irradiation Facility for Long Term Animal Exposures at Colorado State University Michael Weil Colorado State University Abstract A low dose rate irradiation facility...

412

Latest Research, Response to Fukushima, Integrating Low Dose...  

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

Latest Research, Response to Fukushima, Integrating Low Dose into Policy-All Featured at Annual Investigators' Workshop The 10th DOE Low Dose Radiation Research Program...

413

Low Dose Radiation Research Program: Depletion of the Vertebrate...  

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

Laboratory, Berkeley, California To better understand the responses to low dose ionizing radiation, we proposed in Aim 1 of our Low Dose grant to use dominant-negative...

414

RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS  

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

RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS RADIOPHARMACEUTICALS Latest Revision Date: 43096 Radiation Internal Dose Information Center Oak Ridge Institute for...

415

Low Dose Radiation Research Program Website ?? Highlighting...  

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

Website Highlighting Low Dose Research Bill Morgan Pacific Northwest National Laboratory Abstract The Low Dose Radiation Research Programs website is found at http:...

416

Low Dose Radiation Research Program: Genomic Instability and...  

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

Genomic Instability and Low Dose Low Dose Rate Radiation. Authors: Lei Huang, Suzanne Grim, William F. Morgan Institutions: University of Maryland. Humans will always receive...

417

Low Dose Radiation Program: Links - General Radiation Information  

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

General Radiation Information Answers to Questions about Radiation Dose Ranges Charts - tables showing radiation dose ranges from radio diagnostics to cancer radiotherapy....

418

Low Dose Radiation Research Program Website ? Highlighting Low...  

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

Research Program Website - Highlighting Low Dose Research Bill Morgan, Principal Investigator; Julie Wiley, Website Content Manager; Christine Novak, Webmaster The Low Dose...

419

Low Dose Investigator one of Canada's Top 40  

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

Low Dose Investigator one of Canada's Top 40 Olga Kovalchuk Congratulations to Low Dose Radiation Research Program investigator Olga Kovalchuk on being named one of "Canada's Top...

420

Hands-on Energy Adaptation Toolkit (HEAT) | Open Energy Information  

Open Energy Info (EERE)

Hands-on Energy Adaptation Toolkit (HEAT) Hands-on Energy Adaptation Toolkit (HEAT) Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Hands-on Energy Adaptation Toolkit (HEAT) Agency/Company /Organization: Energy Sector Management Assistance Program of the World Bank Sector: Energy Focus Area: Renewable Energy Topics: Adaptation, Implementation, Pathways analysis Resource Type: Guide/manual Website: esmap.org/esmap/node/312 Hands-on Energy Adaptation Toolkit (HEAT) Screenshot References: HEAT[1] Background "HEAT- A Hands-on Energy Adaptation Toolkit is designed to lead you through as assessment of climate vulnerabilities and adaptation options in the energy sector of your country. HEAT can help you raise awareness among key stakeholders and initiate dialogue on energy sector adaptation.

Note: This page contains sample records for the topic "dose radiation-induced adaptive" from the National Library of EnergyBeta (NLEBeta).
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421

Idealized Adaptive Observation Strategies for Improving Numerical Weather Prediction  

Science Conference Proceedings (OSTI)

Adaptive sampling uses information about individual atmospheric situations to identify regions where additional observations are likely to improve weather forecasts of interest. The observation network could be adapted for a wide range of ...

Rebecca E. Morss; Kerry A. Emanuel; Chris Snyder

2001-01-01T23:59:59.000Z

422

Clustering using adaptive self-organizing maps (ASOM) and applications  

Science Conference Proceedings (OSTI)

This paper presents an innovative, adaptive variant of Kohonen's self-organizing maps called ASOM, which is an unsupervised clustering method that adaptively decides on the best architecture for the self-organizing map. Like the traditional SOMs, ...

Yong Wang; Chengyong Yang; Kalai Mathee; Giri Narasimhan

2005-05-01T23:59:59.000Z

423

Urban climate resilience : a global assessment of city adaptation plans  

E-Print Network (OSTI)

As policy makers accept climate change as an irrefutable threat, adaptation planning has emerged as a necessary action for countries, states, and municipalities. This thesis explores adaptive responses to climate change ...

Katich, Kristina Noel

2009-01-01T23:59:59.000Z

424

Modelling sequential text with an adaptive topic model  

Science Conference Proceedings (OSTI)

Topic models are increasingly being used for text analysis tasks, often times replacing earlier semantic techniques such as latent semantic analysis. In this paper, we develop a novel adaptive topic model with the ability to adapt topics from both the ...

Lan Du; Wray Buntine; Huidong Jin

2012-07-01T23:59:59.000Z

425

A Comparison of Adaptive Observing Guidance for Atlantic Tropical Cyclones  

Science Conference Proceedings (OSTI)

Airborne adaptive observations have been collected for more than two decades in the neighborhood of tropical cyclones, to attempt to improve short-range forecasts of cyclone track. However, only simple subjective strategies for adaptive ...

S. J. Majumdar; S. D. Aberson; C. H. Bishop; R. Buizza; M. S. Peng; C. A. Reynolds

2006-09-01T23:59:59.000Z

426

Architectures for Adaptive Low-Power Embedded Multimedia Systems.  

E-Print Network (OSTI)

??This Ph.D. thesis describes novel hardware/software architectures for adaptive low-power embedded multimedia systems. Novel techniques for run-time adaptive energy management are proposed, such that both (more)

Shafique, Muhammad

2011-01-01T23:59:59.000Z

427

ADAPT: abstraction hierarchies to better simulate teamwork under dynamics  

Science Conference Proceedings (OSTI)

In this paper we present a lightweight teamwork implementation by using abstraction hierarchies. The basis of this implementation is ADAPT, which supports Autonomous Dynamic Agent Planning for Teamwork. ADAPT's novelty ...

Meirav Hadad; Avi Rosenfeld

2011-05-01T23:59:59.000Z

428

An Adaptive Multigrid Barotropic Tropical Cyclone Track Model  

Science Conference Proceedings (OSTI)

This paper describes the application of adaptive multigrid techniques to the problem of tropical cyclone track prediction. Based on the nondivergent barotropic vorticity equation, the model uses an adaptive multigrid method to refine the mesh ...

Scott R. Fulton

2001-01-01T23:59:59.000Z

429

Historical river flow rates for dose calculations  

Science Conference Proceedings (OSTI)

Annual average river flow rates are required input to the LADTAP Computer Code for calculating offsite doses from liquid releases of radioactive materials to the Savannah River. The source of information on annual river flow rates used in dose calculations varies, depending on whether calculations are for retrospective releases or prospective releases. Examples of these types of releases are: Retrospective - releases from routine operations (annual environmental reports) and short term release incidents that have occurred. Prospective - releases that might be expected in the future from routine or abnormal operation of existing or new facilities (EIS`s, EID`S, SAR`S, etc.). This memorandum provides historical flow rates at the downstream gauging station at Highway 301 for use in retrospective dose calculations and derives flow rate data for the Beaufort-Jasper and Port Wentworth water treatment plants.

Carlton, W.H.

1991-06-10T23:59:59.000Z

430

Radiotherapy Dose Fractionation under Parameter Uncertainty  

SciTech Connect

In radiotherapy, radiation is directed to damage a tumor while avoiding surrounding healthy tissue. Tradeoffs ensue because dose cannot be exactly shaped to the tumor. It is particularly important to ensure that sensitive biological structures near the tumor are not damaged more than a certain amount. Biological tissue is known to have a nonlinear response to incident radiation. The linear quadratic dose response model, which requires the specification of two clinically and experimentally observed response coefficients, is commonly used to model this effect. This model yields an optimization problem giving two different types of optimal dose sequences (fractionation schedules). Which fractionation schedule is preferred depends on the response coefficients. These coefficients are uncertainly known and may differ from patient to patient. Because of this not only the expected outcomes but also the uncertainty around these outcomes are important, and it might not be prudent to select the strategy with the best expected outcome.

Davison, Matt [Department of Applied Mathematics, University of Western Ontario, London, Ontario (Canada); Department of Statistical and Actuarial Science, University of Western Ontario, London, Ontario (Canada); Ivey School of Business, University of Western Ontario, London, Ontario (Canada); Kim, Daero [Department of Applied Mathematics, University of Western Ontario, London, Ontario (Canada); Keller, Harald [Department Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada)

2011-11-30T23:59:59.000Z

431

Lossless compression using the adaptive discrete cosine transform  

Science Conference Proceedings (OSTI)

This paper describes a technique using the adaptive discrete cosine transform for lossless waveform data compression. The technique is a variation on a two-stage lossless method that was developed by one of the authors. The earlier work employed an adaptive ... Keywords: ADPCM scheme, adaptive differential pulse code modulation-type, adaptive discrete cosine transform, data compression, encoding, integer residual sequence, lossless successive difference operation, lossless waveform data compression, storage, transmission, two-stage lossless method

L. Gerhardt; M. Fargues; G. Coutu

1995-10-01T23:59:59.000Z

432

Microstructure Stability of Multi-Materials Systems with Adaptive ...  

Science Conference Proceedings (OSTI)

Materials Genomics Past & Future: From CALPHAD to Flight Microstructure Stability of Multi-Materials Systems with Adaptive Microstructures Modeling of...

433

Multi-AUV control and adaptive sampling  

E-Print Network (OSTI)

Abstract Multi-AUV operations have much to offer a variety of underwater applications. With sensors to measure the environment and coordination that is appropriate to critical spatial and temporal scales, the group can perform important tasks such as adaptive ocean sampling. We describe a methodology for cooperative control of multiple vehicles based on virtual bodies and artificial potentials (VBAP). This methodology allows for adaptable formation control and can be used for missions such as gradient climbing and feature tracking in an uncertain environment. We discuss our implementation on a fleet of autonomous underwater gliders and present results from sea trials in Monterey Bay in August 2003. These at-sea demonstrations were performed as part of the Autonomous Ocean Sampling Network (AOSN) II project.

Monterey Bay; Edward Fiorelli; Naomi Ehrich Leonard; Pradeep Bhatta; Derek Paley; Ralf Bachmayer

2004-01-01T23:59:59.000Z

434

Adaptive iterative multiscale finite volume method  

Science Conference Proceedings (OSTI)

The multiscale finite volume (MSFV) method is a computationally efficient numerical method for the solution of elliptic and parabolic problems with heterogeneous coefficients. It has been shown for a wide range of test cases that the MSFV results are ... Keywords: Adaptive multiscale method, Elliptic problem, Infrequently localization improvement, Iterative multiscale finite-volume method, Iterative multiscale method, Multiphase flow, Multiscale finite-volume method, Multiscale method, Porous media

Hadi Hajibeygi; Patrick Jenny

2011-02-01T23:59:59.000Z

435

Robust adaptive control of HVDC systems  

SciTech Connect

The transient performance of an HVDC power system is highly dependent on the parameters of the current/voltage regulators of the converter controls. In order to better accommodate changes in system structure or dc operating conditions, this paper introduces a new adaptive control strategy. The advantages of automatic tuning for continuous fine tuning are combined with predetermined gain scheduling in order to achieve robustness for large disturbances. Examples are provided for a digitally simulated back-to-back dc system.

Reeve, J.; Sultan, M. (Univ. of Waterloo, Ontario (Canada))

1994-07-01T23:59:59.000Z

436

User-Centered Adaptive Information Retrieval  

E-Print Network (OSTI)

Information retrieval systems are critical for overcoming information overload. A major deficiency of existing retrieval systems is that they generally lack user modeling and are not adaptive to individual users; information about the actual user and search context is largely ignored. For example, a tourist and a programmer may use the same word "java" to search for different information, but the current retrieval systems would return the same results. In the proposed

Xuehua Shen

2006-01-01T23:59:59.000Z

437

Documentation of the Irvine Integrated Corridor Freeway Ramp Metering and Arterial Adaptive Control Field Operational Test  

E-Print Network (OSTI)

Integrated Ramp Metering/Adaptive Signal Control FieldIntegrated Ramp Metering/Adaptive Signal Control FieldTest Plan," Integrated Ramp Metering/Adaptive Signal Control

McNally, M. G.; Moore, II, James E.; MacCarley, C. Arthur

2001-01-01T23:59:59.000Z

438

Asynchronous ARM processor employing an adaptive pipeline architecture  

Science Conference Proceedings (OSTI)

This paper presented an asynchronous ARM processor employing adaptive pipeline and enhanced control schemes. This adaptive pipeline employed stage-skipping and stage-combining. The stage-skipping removed the redundant stage operations, bubbles. The stage-combining ... Keywords: adaptive pipeline, asynchronous design, processor

Je-Hoon Lee; Seung-Sook Lee; Kyoung-Rok Cho

2007-03-01T23:59:59.000Z

439

Adaptare: Supporting automatic and dependable adaptation in dynamic environments  

Science Conference Proceedings (OSTI)

Distributed protocols executing in uncertain environments, like the Internet or ambient computing systems, should dynamically adapt to environment changes in order to preserve Quality of Service (QoS). In earlier work, it was shown that QoS adaptation ... Keywords: Adaptation, dependability, probabilistic analysis, quality of service

Mnica Dixit; Antnio Casimiro; Paolo Lollini; Andrea Bondavalli; Paulo Verissimo

2012-07-01T23:59:59.000Z

440

Moving target defense (MTD) in an adaptive execution environment  

Science Conference Proceedings (OSTI)

This paper describes how adaptation support facilitated by an execution environment can be used to implement moving target defenses (MTD). Reactive and proactive use of adaptation, although beneficial for cyber defense, comes with additional cost, and ... Keywords: cost, moving target defense, proactive and reactive adaptation

A. Paulos; P. Pal; R. Schantz; B. Benyo

2013-01-01T23:59:59.000Z