Sample records for dose radiation-induced adaptive

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

    SciTech Connect (OSTI)

    Jian Li

    2012-11-07T23:59:59.000Z

    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.

  2. EXTRAPOLATING RADIATION-INDUCED CANCER RISKS FROM LOW DOSES TO VERY LOW DOSES

    E-Print Network [OSTI]

    Brenner, David Jonathan

    risk; National Council on Radiation Protection and Measurements INTRODUCTION THERE IS considerablePaper EXTRAPOLATING RADIATION-INDUCED CANCER RISKS FROM LOW DOSES TO VERY LOW DOSES David J. Brenner* Abstract--There is strong evidence that ionizing radiation increases cancer risks at high doses

  3. Radiation-induced chromosomal aberrations at different dose-rates

    E-Print Network [OSTI]

    McDaniel, Jackson Dean

    1965-01-01T23:59:59.000Z

    and sincere gratitude to Dr. G. M. Krise, for his advice and generosity, and to Dr. S. 0. Brown, for his vigilance throughout the course of this investigaticn. To Dr. H. R. Crookshank, I would like to acknowledge my indebtedness for serving as a sember... testicular cells eight hours postirradiation in animals given a total-body dose of 300 r at various dose rates . ; . . . . . . . . . . . , . . . . . . . . . . 17 II. Percentage of cells with aberrations per total dividing cells in the rat testes eight...

  4. The prediction of radiation-induced liver dysfunction using a local dose and regional venous perfusion model

    SciTech Connect (OSTI)

    Cao Yue; Platt, Joel F.; Francis, Isaac R; Balter, James M.; Pan, Charlie; Normolle, Daniel; Ben-Josef, Edgar; Haken, Randall K. ten; Lawrence, Theodore S. [Departments of Radiation Oncology and Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States); Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-0010 (United States)

    2007-02-15T23:59:59.000Z

    We have shown that high dose conformal radiation combined with chemotherapy appears to prolong the survival of patients with unresectable intrahepatic cancers. The ability to safely deliver higher doses is primarily limited by the development of radiation-induced liver disease, characterized by venous occlusion. In this study, we investigated whether portal venous perfusion measured prior to the end of radiation therapy (RT) together with dose could predict liver venous perfusion dysfunction after treatment. Ten patients with unresectable intrahepatic cancer participated in an IRB-approved computer tomography (CT) perfusion study. Hepatic arterial and portal vein perfusion distributions were estimated by using dynamic contrast enhanced CT and the single compartmental model. Scans were obtained at four time points: prior to treatment, after 15 and 30 fractions of 1.5 Gy treatments, and one month following the completion of RT. Multivariant linear regression was used to determine covariances among the first three time point measurements plus dose for prediction of the post RT measurement. The reduction in the regional venous perfusion one month following RT was predicted by the local accumulated dose and the change in the regional venous perfusion after {approx}30 fractions (F=90.6,p<0.000 01). Each Gy produced an approximately 1.2% of reduction in the venous perfusion. This local dose and venous perfusion model has the potential to predict individual sensitivity to radiation. This is the first step toward developing a method to deliver higher and potentially more curative radiation doses to the patients who can safely receive these higher doses.

  5. A Systems Genetic Approach to Identify Low Dose Radiation-Induced Lymphoma Susceptibility/DOE2013FinalReport

    SciTech Connect (OSTI)

    Balmain, Allan [University of California, San Francisco; Song, Ihn Young [University of California, San Francisco

    2013-05-15T23:59:59.000Z

    The ultimate goal of this project is to identify the combinations of genetic variants that confer an individual's susceptibility to the effects of low dose (0.1 Gy) gamma-radiation, in particular with regard to tumor development. In contrast to the known effects of high dose radiation in cancer induction, the responses to low dose radiation (defined as 0.1 Gy or less) are much less well understood, and have been proposed to involve a protective anti-tumor effect in some in vivo scientific models. These conflicting results confound attempts to develop predictive models of the risk of exposure to low dose radiation, particularly when combined with the strong effects of inherited genetic variants on both radiation effects and cancer susceptibility. We have used a ??Systems Genetics approach in mice that combines genetic background analysis with responses to low and high dose radiation, in order to develop insights that will allow us to reconcile these disparate observations. Using this comprehensive approach we have analyzed normal tissue gene expression (in this case the skin and thymus), together with the changes that take place in this gene expression architecture a) in response to low or high- dose radiation and b) during tumor development. Additionally, we have demonstrated that using our expression analysis approach in our genetically heterogeneous/defined radiation-induced tumor mouse models can uniquely identify genes and pathways relevant to human T-ALL, and uncover interactions between common genetic variants of genes which may lead to tumor susceptibility.

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

    SciTech Connect (OSTI)

    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

    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.

  7. Time dependent annealing of radiation - induced leakage currents in MOS devices

    SciTech Connect (OSTI)

    Terrell, J.M. (Booz Allen and Hamilton, Inc. Bethesda, MD (US)); Olkham, T.R.; Lelis, A.J.; Benedetto, J.M. (Harry Diamond Labs., Adelphi, MD (US))

    1989-12-01T23:59:59.000Z

    Results are presented showing the radiation response of several unhardened commercial 1.25-{mu}m bulk CMOS processes using LOCOS isolation technology. In all cases studied radiation-induced failure is caused by effects in the field oxide, and the radiation-induced {delta}V{sub T} in the channel region is usually small at the failure dose. Time dependent leakage current data for the field oxides are presented and discussed.

  8. Adaptive Noise Reduction toward Low-dose Computed Tomography Hongbing Lu*ad

    E-Print Network [OSTI]

    Adaptive Noise Reduction toward Low-dose Computed Tomography Hongbing Lu*ad , Xiang Lia , Lihong phantom projections acquired by a GE spiral computed tomography (CT) scanner under 10 mAs tube current, computed tomography, adaptive filtering, edge- preserving smoothing, streak artifacts. 1. INTRODUCTION

  9. adaptive dose escalation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  10. Transient radiation-induced absorption in laser materials

    SciTech Connect (OSTI)

    Brannon, P.J.

    1994-12-31T23:59:59.000Z

    Transient radiation-induced absorption losses in laser materials have been measured using a pulsed nuclear reactor. Reactor pulse widths of 70 to 90 {mu}s and absorbed doses of 1 to 7.5 krad have been used. Transmission recovery times and peak absorption coefficients are given. Materials tested include LiNbO{sub 3}, GSGG, silica substrates, and filter glasses used in the laser cavity. The filter glasses are tested at discrete wavelengths in the range 440--750 nm. Lithium niobate , MgO doped LiNbO{sub 3}, GSGG, and the silica substrates are tested at 1061 nm.

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

    SciTech Connect (OSTI)

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

    2013-05-01T23:59:59.000Z

    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.

  12. Radiation-Induced Reduction of Ceria in Single and Polycrystalline...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Radiation-Induced Reduction of Ceria in Single and Polycrystalline Thin Films. Radiation-Induced Reduction of Ceria in Single and Polycrystalline Thin Films. Abstract: Ceria (CeO2)...

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

    SciTech Connect (OSTI)

    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

    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.

  14. Parotid Glands DoseEffect Relationships Based on Their Actually Delivered Doses: Implications for Adaptive Replanning in Radiation Therapy of Head-and-Neck Cancer

    SciTech Connect (OSTI)

    Hunter, Klaudia U. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Fernandes, Laura L. [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Vineberg, Karen A.; McShan, Daniel; Antonuk, Alan E. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cornwall, Craig [Department of Hospital Dentistry, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Mathew J. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Balter, James M. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Eisbruch, Avraham, E-mail: eisbruch@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-11-15T23:59:59.000Z

    Purpose: Doses actually delivered to the parotid glands during radiation therapy often exceed planned doses. We hypothesized that the delivered doses correlate better with parotid salivary output than the planned doses, used in all previous studies, and that determining these correlations will help make decisions regarding adaptive radiation therapy (ART) aimed at reducing the delivered doses. Methods and Materials: In this prospective study, oropharyngeal cancer patients treated definitively with chemoirradiation underwent daily cone-beam computed tomography (CBCT) with clinical setup alignment based on the C2 posterior edge. Parotid glands in the CBCTs were aligned by deformable registration to calculate cumulative delivered doses. Stimulated salivary flow rates were measured separately from each parotid gland pretherapy and periodically posttherapy. Results: Thirty-six parotid glands of 18 patients were analyzed. Average mean planned doses was 32 Gy, and differences from planned to delivered mean gland doses were ?4.9 to +8.4 Gy, median difference +2.2 Gy in glands in which delivered doses increased relative to planned. Both planned and delivered mean doses were significantly correlated with posttreatment salivary outputs at almost all posttherapy time points, without statistically significant differences in the correlations. Large dispersions (on average, SD 3.6 Gy) characterized the doseeffect relationships for both. The differences between the cumulative delivered doses and planned doses were evident at first fraction (r=.92, P<.0001) because of complex setup deviations (eg, rotations and neck articulations), uncorrected by the translational clinical alignments. Conclusions: After daily translational setup corrections, differences between planned and delivered doses in most glands were small relative to the SDs of the dosesaliva data, suggesting that ART is not likely to gain measurable salivary output improvement in most cases. These differences were observed at first treatment, indicating potential benefit for more complex setup corrections or adaptive interventions in the minority of patients with large deviations detected early by CBCT.

  15. aminoguanidine alleviates radiation-induced: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    sputtering. In this paper we study several aspects of debris and radiation-induced damage to candidate EUVL source collector optics materials. The first study concerns the use...

  16. Dosimetric Analysis of Radiation-induced Gastric Bleeding

    SciTech Connect (OSTI)

    Feng, Mary, E-mail: maryfeng@umich.edu [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Normolle, Daniel [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States)] [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Pan, Charlie C. [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada)] [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, Ontario (Canada); Amarnath, Sudha [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Ensminger, William D. [Department of Internal Medicine, Division of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Internal Medicine, Division of Hematology Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States); Lawrence, Theodore S.; Ten Haken, Randall K. [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan School of Medicine, Ann Arbor, Michigan (United States)

    2012-09-01T23:59:59.000Z

    Purpose: Radiation-induced gastric bleeding has been poorly understood. In this study, we described dosimetric predictors for gastric bleeding after fractionated radiation therapy. Methods and Materials: The records of 139 sequential patients treated with 3-dimensional conformal radiation therapy (3D-CRT) for intrahepatic malignancies were reviewed. Median follow-up was 7.4 months. The parameters of a Lyman normal tissue complication probability (NTCP) model for the occurrence of {>=}grade 3 gastric bleed, adjusted for cirrhosis, were fitted to the data. The principle of maximum likelihood was used to estimate parameters for NTCP models. Results: Sixteen of 116 evaluable patients (14%) developed gastric bleeds at a median time of 4.0 months (mean, 6.5 months; range, 2.1-28.3 months) following completion of RT. The median and mean maximum doses to the stomach were 61 and 63 Gy (range, 46-86 Gy), respectively, after biocorrection of each part of the 3D dose distributions to equivalent 2-Gy daily fractions. The Lyman NTCP model with parameters adjusted for cirrhosis predicted gastric bleed. Best-fit Lyman NTCP model parameters were n=0.10 and m=0.21 and with TD{sub 50} (normal) = 56 Gy and TD{sub 50} (cirrhosis) = 22 Gy. The low n value is consistent with the importance of maximum dose; a lower TD{sub 50} value for the cirrhosis patients points out their greater sensitivity. Conclusions: This study demonstrates that the Lyman NTCP model has utility for predicting gastric bleeding and that the presence of cirrhosis greatly increases this risk. These findings should facilitate the design of future clinical trials involving high-dose upper abdominal radiation.

  17. Radiation induced strand breakage analyzed by tunel technique

    E-Print Network [OSTI]

    Reynolds, Marissa Dawn

    2003-01-01T23:59:59.000Z

    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...

  18. Radiation induced by relativistic beams passing over a diffraction...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    August 2000 FEL 2000 1 Radiation Induced by Relativistic Beams Passing Over a Diffraction Grating J.H. Brownell, J. Walsh, J. Swartz, S. Trotz Dept. of Physics and Astronomy,...

  19. Radiation induced strand breakage analyzed by tunel technique

    E-Print Network [OSTI]

    Reynolds, Marissa Dawn

    2003-01-01T23:59:59.000Z

    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...

  20. Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy

    E-Print Network [OSTI]

    Andritschky, M; Mathewson, A G; Souchet, R; Strubin, Pierre M; Trickett, B A

    1990-01-01T23:59:59.000Z

    Differences in synchrotron radiation induced gas desorption from stainless steel and aluminium alloy

  1. Adaptation of the CVT algorithm for catheter optimization in high dose rate brachytherapy

    SciTech Connect (OSTI)

    Poulin, Eric; Fekete, Charles-Antoine Collins; Beaulieu, Luc [Dpartement de Physique, de Gnie Physique et dOptique et Centre de recherche sur le cancer de lUniversit Laval, Universit Laval, Qubec, Qubec G1V 0A6, Canada and Dpartement de Radio-Oncologie et Axe oncologie du Centre de Recherche du CHU de Qubec, CHU de Qubec, 11 Cte du Palais, Qubec, Qubec G1R 2J6 (Canada)] [Dpartement de Physique, de Gnie Physique et dOptique et Centre de recherche sur le cancer de lUniversit Laval, Universit Laval, Qubec, Qubec G1V 0A6, Canada and Dpartement de Radio-Oncologie et Axe oncologie du Centre de Recherche du CHU de Qubec, CHU de Qubec, 11 Cte du Palais, Qubec, Qubec G1R 2J6 (Canada); Ltourneau, Mlanie [Dpartement de Radio-Oncologie, CHU de Qubec, 11 Cte du Palais, Qubec, Qubec G1R 2J6 (Canada)] [Dpartement de Radio-Oncologie, CHU de Qubec, 11 Cte du Palais, Qubec, Qubec G1R 2J6 (Canada); Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (United Kingdom)] [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (United Kingdom); Pouliot, Jean [Department of Radiation Oncology, University of California San Francisco, Helen Diller Family Comprehensive Cancer Center, 1600 Divisadero Street, San Francisco, California 94143-1708 (United States)] [Department of Radiation Oncology, University of California San Francisco, Helen Diller Family Comprehensive Cancer Center, 1600 Divisadero Street, San Francisco, California 94143-1708 (United States)

    2013-11-15T23:59:59.000Z

    Purpose: An innovative, simple, and fast method to optimize the number and position of catheters is presented for prostate and breast high dose rate (HDR) brachytherapy, both for arbitrary templates or template-free implants (such as robotic templates).Methods: Eight clinical cases were chosen randomly from a bank of patients, previously treated in our clinic to test our method. The 2D Centroidal Voronoi Tessellations (CVT) algorithm was adapted to distribute catheters uniformly in space, within the maximum external contour of the planning target volume. The catheters optimization procedure includes the inverse planning simulated annealing algorithm (IPSA). Complete treatment plans can then be generated from the algorithm for different number of catheters. The best plan is chosen from different dosimetry criteria and will automatically provide the number of catheters and their positions. After the CVT algorithm parameters were optimized for speed and dosimetric results, it was validated against prostate clinical cases, using clinically relevant dose parameters. The robustness to implantation error was also evaluated. Finally, the efficiency of the method was tested in breast interstitial HDR brachytherapy cases.Results: The effect of the number and locations of the catheters on prostate cancer patients was studied. Treatment plans with a better or equivalent dose distributions could be obtained with fewer catheters. A better or equal prostate V100 was obtained down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of prostate V100 and D90. Implantation errors up to 3 mm were acceptable since no statistical difference was found when compared to 0 mm error (p > 0.05). No significant difference in dosimetric indices was observed for the different combination of parameters within the CVT algorithm. A linear relation was found between the number of random points and the optimization time of the CVT algorithm. Because the computation time decrease with the number of points and that no effects were observed on the dosimetric indices when varying the number of sampling points and the number of iterations, they were respectively fixed to 2500 and to 100. The computation time to obtain ten complete treatments plans ranging from 9 to 18 catheters, with the corresponding dosimetric indices, was 90 s. However, 93% of the computation time is used by a research version of IPSA. For the breast, on average, the Radiation Therapy Oncology Group recommendations would be satisfied down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of V100, dose homogeneity index, and D90.Conclusions: The authors have devised a simple, fast and efficient method to optimize the number and position of catheters in interstitial HDR brachytherapy. The method was shown to be robust for both prostate and breast HDR brachytherapy. More importantly, the computation time of the algorithm is acceptable for clinical use. Ultimately, this catheter optimization algorithm could be coupled with a 3D ultrasound system to allow real-time guidance and planning in HDR brachytherapy.

  2. Radiation-induced complications in prostate cancer patients treated with radiotherapy

    SciTech Connect (OSTI)

    Azuddin, A. Yusof [School of Applied Physics, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia and Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 53000 Kuala Lumpur (Malaysia); Rahman, I. Abdul; Mohamed, F. [School of Applied Physics, Faculty of Sciences and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Siah, N. J. [Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 53000 Kuala Lumpur (Malaysia); Saadc, M. [Department of Oncology, University Malaya Medical Center, 50603 Kuala Lumpur (Malaysia); Ismail, F. [Department of Oncology and Radiotherapy, Universiti Kebangsaan Malaysia Medical Centre, 56000 Cheras, Kuala Lumpur (Malaysia)

    2014-09-03T23:59:59.000Z

    The purpose of the study is to determine the relationship between radiation-induced complications with dosimetric and radiobiological parameters for prostate cancer patients that underwent the conformal radiotherapy treatment. 17 prostate cancer patients that have been treated with conformal radiotherapy were retrospectively analysed. The dosimetric data was retrieved in the form of dose-volume histogram (DVH) from Radiotherapy Treatment Planning System. The DVH was utilised to derived Normal Tissue Complication Probability (NTCP) in radiobiological data. Follow-up data from medical records were used to grade the occurrence of acute gastrointestinal (GI) and genitourinary (GU) complications using Radiation Therapy Oncology Group (RTOG) scoring system. The chi-square test was used to determine the relationship between radiation-induced complication with dosimetric and radiobiological parameters. 8 (47%) and 7 (41%) patients were having acute GI and GU complications respectively. The acute GI complication can be associated with V60{sub rectum}, rectal mean dose and NTCP{sub rectum} with p-value of 0.016, 0.038 and 0.049 respectively. There are no significant relationships of acute GU complication with dosimetric and radiobiological variables. Further study can be done by increase the sample size and follow up duration for deeper understanding of the factors that effecting the GU and GI complication in prostate cancer radiotherapy.

  3. Modeling radiation-induced mixing at interfaces between low solubility metals

    E-Print Network [OSTI]

    Zhang, Liang, Ph. D. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    This thesis studies radiation-induced mixing at interfaces between low solubility metals using molecular dynamics (MD) computer simulations. It provides original contributions on the fundamental mechanisms of radiation-induced ...

  4. Roles of Sensory Nerves in the Regulation of Radiation-Induced Structural and Functional Changes in the Heart

    SciTech Connect (OSTI)

    Sridharan, Vijayalakshmi; Tripathi, Preeti [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Sharma, Sunil [Department of Radiation Oncology, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Moros, Eduardo G. [Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida (United States); Zheng, Junying [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Hauer-Jensen, Martin [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States); Surgical Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas (United States); Boerma, Marjan, E-mail: mboerma@uams.edu [Department of Pharmaceutical Sciences, Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas (United States)

    2014-01-01T23:59:59.000Z

    Purpose: Radiation-induced heart disease (RIHD) is a chronic severe side effect of radiation therapy of intrathoracic and chest wall tumors. The heart contains a dense network of sensory neurons that not only are involved in monitoring of cardiac events such as ischemia and reperfusion but also play a role in cardiac tissue homeostasis, preconditioning, and repair. The purpose of this study was to examine the role of sensory nerves in RIHD. Methods and Materials: Male Sprague-Dawley rats were administered capsaicin to permanently ablate sensory nerves, 2 weeks before local image-guided heart x-ray irradiation with a single dose of 21 Gy. During the 6 months of follow-up, heart function was assessed with high-resolution echocardiography. At 6 months after irradiation, cardiac structural and molecular changes were examined with histology, immunohistochemistry, and Western blot analysis. Results: Capsaicin pretreatment blunted the effects of radiation on myocardial fibrosis and mast cell infiltration and activity. By contrast, capsaicin pretreatment caused a small but significant reduction in cardiac output 6 months after irradiation. Capsaicin did not alter the effects of radiation on cardiac macrophage number or indicators of autophagy and apoptosis. Conclusions: These results suggest that sensory nerves, although they play a predominantly protective role in radiation-induced cardiac function changes, may eventually enhance radiation-induced myocardial fibrosis and mast cell activity.

  5. Radiation-Induced Segregation and Phase Stability in Candidate Alloys for the Advanced Burner Reactor

    SciTech Connect (OSTI)

    Gary S. Was; Brian D. Wirth

    2011-05-29T23:59:59.000Z

    Major accomplishments of this project were the following: 1) Radiation induced depletion of Cr occurs in alloy D9, in agreement with that observed in austenitic alloys. 2) In F-M alloys, Cr enriches at PAG grain boundaries at low dose (<7 dpa) and at intermediate temperature (400C) and the magnitude of the enrichment decreases with temperature. 3) Cr enrichment decreases with dose, remaining enriched in alloy T91 up to 10 dpa, but changing to depletion above 3 dpa in HT9 and HCM12A. 4) Cr has a higher diffusivity than Fe by a vacancy mechanism and the corresponding atomic flux of Cr is larger than Fe in the opposite direction to the vacancy flux. 5) Cr concentration at grain boundaries decreases as a result of vacancy transport during electron or proton irradiation, consistent with Inverse Kirkendall models. 6) Inclusion of other point defect sinks into the KLMC simulation of vacancy-mediated diffusion only influences the results in the low temperature, recombination dominated regime, but does not change the conclusion that Cr depletes as a result of vacancy transport to the sink. 7) Cr segregation behavior is independent of Frenkel pair versus cascade production, as simulated for electron versus proton irradiation conditions, for the temperatures investigated. 8) The amount of Cr depletion at a simulated planar boundary with vacancy-mediated diffusion reaches an apparent saturation value by about 1 dpa, with the precise saturation concentration dependent on the ratio of Cr to Fe diffusivity. 9) Cr diffuses faster than Fe by an interstitial transport mechanism, and the corresponding atomic flux of Cr is much larger than Fe in the same direction as the interstitial flux. 10) Observed experimental and computational results show that the radiation induced segregation behavior of Cr is consistent with an Inverse Kirkendall mechanism.

  6. A self-adaptive case-based reasoning system for dose planning in prostate cancer radiotherapy

    SciTech Connect (OSTI)

    Mishra, Nishikant; Petrovic, Sanja; Sundar, Santhanam [Automated Scheduling, Optimisation and Planning Research Group, School of Computer Science, University of Nottingham, Nottingham NG8 1BB (United Kingdom); Department of Oncology, Nottingham University Hospitals NHS Trust, Nottingham NG5 1PB (United Kingdom)

    2011-12-15T23:59:59.000Z

    Purpose: Prostate cancer is the most common cancer in the male population. Radiotherapy is often used in the treatment for prostate cancer. In radiotherapy treatment, the oncologist makes a trade-off between the risk and benefit of the radiation, i.e., the task is to deliver a high dose to the prostate cancer cells and minimize side effects of the treatment. The aim of our research is to develop a software system that will assist the oncologist in planning new treatments. Methods: A nonlinear case-based reasoning system is developed to capture the expertise and experience of oncologists in treating previous patients. Importance (weights) of different clinical parameters in the dose planning is determined by the oncologist based on their past experience, and is highly subjective. The weights are usually fixed in the system. In this research, the weights are updated automatically each time after generating a treatment plan for a new patient using a group based simulated annealing approach. Results: The developed approach is analyzed on the real data set collected from the Nottingham University Hospitals NHS Trust, City Hospital Campus, UK. Extensive experiments show that the dose plan suggested by the proposed method is coherent with the dose plan prescribed by an experienced oncologist or even better. Conclusions: The developed case-based reasoning system enables the use of knowledge and experience gained by the oncologist in treating new patients. This system may play a vital role to assist the oncologist in making a better decision in less computational time; it utilizes the success rate of the previously treated patients and it can also be used in teaching and training processes.

  7. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

    Bu Wang; Yingtian Yu; Isabella Pignatelli; Gaurav N. Sant; Mathieu Bauchy

    2015-04-10T23:59:59.000Z

    Although quartz ($\\rm \\alpha$-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage have not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics (MD) simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si--O connectivity defects, e.g., small Si--O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on $E^{\\prime}$ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependence on the incident energy, of the amount of each type of the point defects formed, and quantify unambiguously the threshold displacement energies for both O and Si atoms. These results provide a comprehensive basis to assess the nature and extent of radiation damage in quartz.

  8. Radiative acceleration and transient, radiation-induced electric fields

    E-Print Network [OSTI]

    L. Zampieri; R. Turolla; L. Foschini; A. Treves

    2003-04-14T23:59:59.000Z

    The radiative acceleration of particles and the electrostatic potential fields that arise in low density plasmas hit by radiation produced by a transient, compact source are investigated. We calculate the dynamical evolution and asymptotic energy of the charged particles accelerated by the photons and the radiation-induced electric double layer in the full relativistic, Klein-Nishina regime. For fluxes in excess of $10^{27}$ ${\\rm erg} {\\rm cm}^{-2} {\\rm s}^{-1}$, the radiative force on a diluted plasma ($n\\la 10^{11}$ cm$^{-3}$) is so strong that electrons are accelerated rapidly to relativistic speeds while ions lag behind owing to their larger inertia. The ions are later effectively accelerated by the strong radiation-induced double layer electric field up to Lorentz factors $\\approx 100$, attainable in the case of negligible Compton drag. The asymptotic energies achieved by both ions and electrons are larger by a factor 2--4 with respect to what one could naively expect assuming that the electron-ion assembly is a rigidly coupled system. The regime we investigate may be relevant within the framework of giant flares from soft gamma-repeaters.

  9. Nature of Radiation-Induced Defects in Quartz

    E-Print Network [OSTI]

    Wang, Bu; Pignatelli, Isabella; Sant, Gaurav N; Bauchy, Mathieu

    2015-01-01T23:59:59.000Z

    Although quartz ($\\rm \\alpha$-form) is a mineral used in numerous applications wherein radiation exposure is an issue, the nature of the atomistic defects formed during radiation-induced damage have not been fully clarified. Especially, the extent of oxygen vacancy formation is still debated, which is an issue of primary importance as optical techniques based on charged oxygen vacancies have been utilized to assess the level of radiation damage in quartz. In this paper, molecular dynamics (MD) simulations are applied to study the effects of ballistic impacts on the atomic network of quartz. We show that the defects that are formed mainly consist of over-coordinated Si and O, as well as Si--O connectivity defects, e.g., small Si--O rings and edge-sharing Si tetrahedra. Oxygen vacancies, on the contrary, are found in relatively low abundance, suggesting that characterizations based on $E^{\\prime}$ centers do not adequately capture radiation-induced structural damage in quartz. Finally, we evaluate the dependenc...

  10. Neurodegeneration and adaptation in response to low-dose photon irradiation

    SciTech Connect (OSTI)

    Limoli, Charles L. [UCI

    2014-10-27T23:59:59.000Z

    Neural stem and precursor cells (i.e. multipotent neural cells) are concentrated in the neurogenic regions of the brain (hippocampal dentate gyrus, subventricular zones), and considerable evidence suggests that these cells are important in mediating the stress response of the CNS after damage from ionizing radiation. The capability of these cells to proliferate, migrate and differentiate (i.e. to undergo neurogenesis) suggests they can participate in the repair and maintenance of CNS functions by replacing brain cells damaged or depleted due to irradiation. Importantly, we have shown that multipotent neural cells are markedly sensitive to irradiation and oxidative stress, insults that compromise neurogenesis and hasten the onset and progression of degenerative processes that are likely to have an adverse impact on cognition. Our past and current work has demonstrated that relatively low doses of radiation cause a persistent (weeks-months) oxidative stress in multipotent neural cells that can elicit a range of degenerative sequelae in the CNS. Therefore, our project is focused on determining the extent that endogenous and redox sensitive multipotent neural cells represent important radioresponsive targets for low dose radiation effects. We hypothesize that the activation of redox sensitive signaling can trigger radioadaptive changes in these cells that can be either harmful or beneficial to overall cognitive health.

  11. Long-term Evaluation of Radiation-Induced Optic Neuropathy After Single-Fraction Stereotactic Radiosurgery

    SciTech Connect (OSTI)

    Leavitt, Jacqueline A., E-mail: leavitt.jacqueline@mayo.edu [Department of Ophthalmology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Stafford, Scott L. [Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Link, Michael J. [Department of Neurosurgery, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Pollock, Bruce E. [Department of Radiation Oncology, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Department of Neurosurgery, Mayo Clinic and Foundation, Rochester, Minnesota (United States)

    2013-11-01T23:59:59.000Z

    Purpose: To determine the long-term risk of radiation-induced optic neuropathy (RION) in patients having single-fraction stereotactic radiosurgery (SRS) for benign skull base tumors. Methods and Materials: Retrospective review of 222 patients having Gamma Knife radiosurgery for benign tumors adjacent to the anterior visual pathway (AVP) between 1991 and 1999. Excluded were patients with prior or concurrent external beam radiation therapy or SRS. One hundred twenty-nine patients (58%) had undergone previous surgery. Tumor types included confirmed World Health Organization grade 1 or presumed cavernous sinus meningioma (n=143), pituitary adenoma (n=72), and craniopharyngioma (n=7). The maximum dose to the AVP was ?8.0 Gy (n=126), 8.1-10.0 Gy (n=39), 10.1-12.0 Gy (n=47), and >12 Gy (n=10). Results: The mean clinical and imaging follow-up periods were 83 and 123 months, respectively. One patient (0.5%) who received a maximum radiation dose of 12.8 Gy to the AVP developed unilateral blindness 18 months after SRS. The chance of RION according to the maximum radiation dose received by the AVP was 0 (95% confidence interval [CI] 0-3.6%), 0 (95% CI 0-10.7%), 0 (95% CI 0-9.0%), and 10% (95% CI 0-43.0%) for patients receiving ?8 Gy, 8.1-10.0 Gy, 10.1-12.0 Gy, and >12 Gy, respectively. The overall risk of RION in patients receiving >8 Gy to the AVP was 1.0% (95% CI 0-6.2%). Conclusions: The risk of RION after single-fraction SRS in patients with benign skull base tumors who have no prior radiation exposure is very low if the maximum dose to the AVP is ?12 Gy. Physicians performing single-fraction SRS should remain cautious when treating lesions adjacent to the AVP, especially when the maximum dose exceeds 10 Gy.

  12. Spatiotemporal characterization of ionizing radiation induced DNA damage foci and their relation to chromatin organization

    E-Print Network [OSTI]

    Costes, Sylvain V

    2010-01-01T23:59:59.000Z

    to ionizing radiation are nuclear marks of permanentto ionizing radiation are nuclear marks of permanentvisible nuclear domains referred to as radiation-induced

  13. Radiation-induced solitary waves in hot plasmas of accretion disks

    E-Print Network [OSTI]

    Fedor V. Prigara

    2005-07-08T23:59:59.000Z

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

  14. attenuates ionizing radiation-induced: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Article Influence of XRCC1 Genetic Polymorphisms on Ionizing Radiation-Induced DNA Damage and Repair CiteSeer Summary: License, which permits unrestricted use, distribution,...

  15. ameliorates radiation-induced lung: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    sputtering. In this paper we study several aspects of debris and radiation-induced damage to candidate EUVL source collector optics materials. The first study concerns the use...

  16. alleviates radiation-induced small-bowel: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    sputtering. In this paper we study several aspects of debris and radiation-induced damage to candidate EUVL source collector optics materials. The first study concerns the use...

  17. Radiation-Induced Decomposition of U(VI) Phase to Nanocrystals of UO2

    SciTech Connect (OSTI)

    S. Utsunomiya; R.C. Ewing; L. Wang

    2005-06-13T23:59:59.000Z

    U{sup 6+}-phases are common alteration products, under oxidizing conditions, of uraninite and the UO{sub 2} in spent nuclear fuel. These U{sup 6+}-phases are subjected to a radiation field caused by the {alpha}-decay of U, or in the case of spent nuclear fuel, incorporated actinides, such as {sup 239}Pu and {sup 237}Np. In order to evaluate the effects of {alpha}-decay events on the stability of the U{sup 6+}-phases, we report, for the first time, the results of ion beam irradiations (1.0 MeV Kr{sup 2+}) of U{sup 6+}-phases. The heavy-particle irradiations are used to simulate the ballistic interactions of the recoil-nucleus of an {alpha}-decay event with the surrounding structure. The Kr{sup 2+}-irradiation decomposed the U{sup 6+}-phases to UO{sub 2} nanocrystals at doses as low as 0.006 displacements per atom (dpa). U{sup 6+}-phases accumulate substantial radiation doses ({approx}1.0 displacement per atom) within 100,000 years if the concentration of incorporated {sup 239}Pu is as high as 1 wt%. Similar nanocrystals of UO{sub 2} were observed in samples from the natural fission reactors at Oklo, Gabon. Multiple cycles of radiation-induced decomposition to UO{sub 2} followed by alteration to U{sup 6+}-phases provide a mechanism for the remobilization of incorporated radionuclides.

  18. Irradiated Esophageal Cells are Protected from Radiation-Induced Recombination by MnSOD Gene Therapy

    E-Print Network [OSTI]

    Engelward, Bevin

    Irradiated Esophageal Cells are Protected from Radiation-Induced Recombination by MnSOD Gene. Irradiated Esophageal Cells are Protected from Radiation- Induced Recombination by MnSOD Gene Therapy. Radiat,a Bevin Engelward,b Michael Epperlya and Joel S. Greenbergera,1 a Departments of Radiation Oncology

  19. Mechanism of radiation-induced bystander effect: Role of the cyclooxygenase-2 signaling pathway

    E-Print Network [OSTI]

    Brenner, David Jonathan

    impact on our thinking as well as immediate application in radiation protection. RadiationMechanism of radiation-induced bystander effect: Role of the cyclooxygenase-2 signaling pathway 25, 2005 (received for review June 30, 2005) The radiation-induced bystander effect is defined

  20. Effects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos in vivo

    E-Print Network [OSTI]

    Yu, K.N.

    -no-threshed (LNT) model widely accepted for radiation protection saying that biological effects caused by ionizingEffects of exogenous carbon monoxide on radiation-induced bystander effect in zebrafish embryos) on the radiation induced bystander effect (RIBE) in vivo between embryos of the zebrafish was studied. RIBE

  1. Mini-review Radiation-induced bystander effect: Early process and rapid assessment

    E-Print Network [OSTI]

    Yu, K.N.

    by the radiation protection agencies. How- ever, this dogma has been challenged by scientific findings since 1990sMini-review Radiation-induced bystander effect: Early process and rapid assessment Hongzhi Wang September 2013 Accepted 26 September 2013 Keywords: Radiation-induced bystander effect Rapid assessment

  2. A physical model of the photo- and radiation-induced degradation of ytterbium-doped silica optical fibres

    SciTech Connect (OSTI)

    Mady, Franck, E-mail: franck.mady@unice.fr; Duchez, Jean-Bernard, E-mail: franck.mady@unice.fr; Mebrouk, Yasmine, E-mail: franck.mady@unice.fr; Benabdesselam, Mourad, E-mail: franck.mady@unice.fr [University of Nice Sophia Antipolis, Laboratoire de Physique de la Matire Condense (LPMC), CNRS UMR 7336, Parc Valrose, 06108 Nice cedex 2 (France)

    2014-10-21T23:59:59.000Z

    We propose a model to describe the photo- or/and the radiation-induced darkening of ytterbium-doped silica optical fibers. This model accounts for the well-established experimental features of photo-darkening. Degradation behaviors predicted for fibers pumped in harsh environments are also fully confirmed by experimental data reported in the work by Duchez et al. (this proceeding), which gives a detailed characterization of the interplay between the effects of the pump and those of a superimposed ionizing irradiation (actual operation conditions in space-based applications for instance). In particular, dependences of the darkening build-up on the pump power, the total ionizing dose and the dose rate are all correctly reproduced. The presented model is a sufficient one, including the minimal physical ingredients required to reproduce experimental features. Refinements could be proposed to improve, e.g., quantitative kinetics.

  3. Amifostine, a radioprotectant agent, protects rat brain tissue lipids against ionizing radiation induced damage: An FTIR microspectroscopic imaging study

    SciTech Connect (OSTI)

    Cakmak G.; Miller L.; Zorlu, F.; Severcan, F.

    2012-03-03T23:59:59.000Z

    Amifostine is the only approved radioprotective agent by FDA for reducing the damaging effects of radiation on healthy tissues. In this study, the protective effect of amifostine against the damaging effects of ionizing radiation on the white matter (WM) and grey matter (GM) regions of the rat brain were investigated at molecular level. Sprague-Dawley rats, which were administered amifostine or not, were whole-body irradiated at a single dose of 800 cGy, decapitated after 24 h and the brain tissues of these rats were analyzed using Fourier transform infrared microspectroscopy (FTIRM). The results revealed that the total lipid content and CH{sub 2} groups of lipids decreased significantly and the carbonyl esters, olefinic=CH and CH{sub 3} groups of lipids increased significantly in the WM and GM after exposure to ionizing radiation, which could be interpreted as a result of lipid peroxidation. These changes were more prominent in the WM of the brain. The administration of amifostine before ionizing radiation inhibited the radiation-induced lipid peroxidation in the brain. In addition, this study indicated that FTIRM provides a novel approach for monitoring ionizing radiation induced-lipid peroxidation and obtaining different molecular ratio images can be used as biomarkers to detect lipid peroxidation in biological systems.

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

    SciTech Connect (OSTI)

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

    2008-11-10T23:59:59.000Z

    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.

  5. Comparison of radiation exposure and associated radiation-induced cancer risks from mammography and molecular imaging of the breast

    SciTech Connect (OSTI)

    O'Connor, Michael K.; Li Hua; Rhodes, Deborah J.; Hruska, Carrie B.; Clancy, Conor B.; Vetter, Richard J. [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Medicine, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Department of Medical Physics, St. James's Hospital, Dublin (Ireland); Radiation Safety, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2010-12-15T23:59:59.000Z

    Purpose: Recent studies have raised concerns about exposure to low-dose ionizing radiation from medical imaging procedures. Little has been published regarding the relative exposure and risks associated with breast imaging techniques such as breast specific gamma imaging (BSGI), molecular breast imaging (MBI), or positron emission mammography (PEM). The purpose of this article was to estimate and compare the risks of radiation-induced cancer from mammography and techniques such as PEM, BSGI, and MBI in a screening environment. Methods: The authors used a common scheme for all estimates of cancer incidence and mortality based on the excess absolute risk model from the BEIR VII report. The lifetime attributable risk model was used to estimate the lifetime risk of radiation-induced breast cancer incidence and mortality. All estimates of cancer incidence and mortality were based on a population of 100 000 females followed from birth to age 80 and adjusted for the fraction that survives to various ages between 0 and 80. Assuming annual screening from ages 40 to 80 and from ages 50 to 80, the cumulative cancer incidence and mortality attributed to digital mammography, screen-film mammography, MBI, BSGI, and PEM was calculated. The corresponding cancer incidence and mortality from natural background radiation was calculated as a useful reference. Assuming a 15%-32% reduction in mortality from screening, the benefit/risk ratio for the different imaging modalities was evaluated. Results: Using conventional doses of 925 MBq Tc-99m sestamibi for MBI and BSGI and 370 MBq F-18 FDG for PEM, the cumulative cancer incidence and mortality were found to be 15-30 times higher than digital mammography. The benefit/risk ratio for annual digital mammography was >50:1 for both the 40-80 and 50-80 screening groups, but dropped to 3:1 for the 40-49 age group. If the primary use of MBI, BSGI, and PEM is in women with dense breast tissue, then the administered doses need to be in the range 75-150 MBq for Tc-99m sestamibi and 35 MBq-70 MBq for F-18 FDG in order to obtain benefit/risk ratios comparable to those of mammography in these age groups. These dose ranges should be achievable with enhancements to current technology while maintaining a reasonable examination time. Conclusions: The results of the dose estimates in this study clearly indicate that if molecular imaging techniques are to be of value in screening for breast cancer, then the administered doses need to be substantially reduced to better match the effective doses of mammography.

  6. SU-E-J-229: Quantitative Assessment for Timely Adaptive Re-Planning Using Weekly Dose Monitoring for Head and Neck Cancer

    SciTech Connect (OSTI)

    Shang, Q; Liu, H; Greskovich, J; Koyfman, S; Xia, P [Cleveland Clinic, Cleveland, OH (United States); Li, Z [Cleveland Clinic, Cleveland, OH (United States); the 6th people's hospital of Shanghai Jiaotong University, Shanghai, Shanghai (China)

    2014-06-01T23:59:59.000Z

    Purpose: For patients with head and neck (HN) cancer, mid-course adaptive radiation therapy (ART) is a common practice in our institution to accommodate anatomic changes. The aim of the study is to evaluate whether dose re-calculation on weekly verification images can provide quantitative assessment for timely adaptive re-planning with daily image-guided intensity modulated radiotherapy (IMRT). Methods: We retrospectively selected sixty daily verification images acquired on CT-on-rail/CBCT from ten HN patients. These image sets were typically a week apart. Among these patients, six patients received a mid-course ART. Contours of the tumors and organ-at-risks (OARs) were manually delineated by a physician on each verification CT. After placing the treatment iso-center on the verification CTs according to the recorded clinical shifts, daily dose was re-calculated with the same beam configuration as the original plan. For the purpose of this study, electron densities for both verification CTs and planning CTs were set to 1.0 g/cm3. Results: Two patients had D99 of the CTV < 97% of the planned dose for more than three fractions due to remarkable tumor volume shrinkages. D-max of the spinal cord exceeded a tolerance of 45 Gy for four fractions in additional two patients. D-mean of the parotid increased within 25% of the planned value. D-max of the brainstem and D-mean of the oral cavity did not show significant variation. If the re-planning criteria included D99 of the CTV < 97% of the planned dose and D-max of the spinal cord > 45 Gy, two out ten patients required ART at week 2 and two patients required ART at week 3, respectively. Conclusion: Weekly dose monitoring with re-calculation on verification images can provide quantitative dose guidance for timely adaptive re-planning. Future work will include accumulative dose analysis for the decision of adaptive re-planning. The study is supported in part by Siemens Medical Solutions.

  7. Poor Baseline Pulmonary Function May Not Increase the Risk of Radiation-Induced Lung Toxicity

    SciTech Connect (OSTI)

    Wang, Jingbo [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States) [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States); Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China); Cao, Jianzhong [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China)] [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China); Yuan, Shuanghu [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States); Ji, Wei [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China)] [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China); Arenberg, Douglas [Department of Internal Medicine, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States)] [Department of Internal Medicine, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States); Dai, Jianrong [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China)] [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China); Stanton, Paul; Tatro, Daniel; Ten Haken, Randall K. [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States); Wang, Luhua, E-mail: wlhwq@yahoo.com [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China)] [Department of Radiation Oncology, Cancer Hospital, Chinese Academic Medical Sciences and Peking Union Medical College, Beijing (China); Kong, Feng-Ming, E-mail: fengkong@med.umich.edu [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan/Ann Arbor Veterans Health System, Ann Arbor, Michigan (United States)

    2013-03-01T23:59:59.000Z

    Purpose: Poor pulmonary function (PF) is often considered a contraindication to definitive radiation therapy for lung cancer. This study investigated whether baseline PF was associated with radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC) receiving conformal radiation therapy (CRT). Methods and Materials: NSCLC patients treated with CRT and tested for PF at baseline were eligible. Baseline predicted values of forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), and diffusion capacity of lung for carbon monoxide (DLCO) were analyzed. Additional factors included age, gender, smoking status, Karnofsky performance status, coexisting chronic obstructive pulmonary disease (COPD), tumor location, histology, concurrent chemotherapy, radiation dose, and mean lung dose (MLD) were evaluated for RILT. The primary endpoint was symptomatic RILT (SRILT), including grade ?2 radiation pneumonitis and fibrosis. Results: There was a total of 260 patients, and SRILT occurred in 58 (22.3%) of them. Mean FEV1 values for SRILT and non-SRILT patients were 71.7% and 65.9% (P=.077). Under univariate analysis, risk of SRILT increased with MLD (P=.008), the absence of COPD (P=.047), and FEV1 (P=.077). Age (65 split) and MLD were significantly associated with SRILT in multivariate analysis. The addition of FEV1 and age with the MLD-based model slightly improved the predictability of SRILT (area under curve from 0.63-0.70, P=.088). Conclusions: Poor baseline PF does not increase the risk of SRILT, and combining FEV1, age, and MLD may improve the predictive ability.

  8. affecting radiation-induced neurological: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    therapeutic effects of IR. Alternate p53 Su, Tin Tin 40 Debris and Radiation-Induced Damage Effects on EUV Nanolithography Source Collector Mirror Optics Performance CiteSeer...

  9. attenuates murine radiation-induced: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2-3. Rupert A. C. Croft; Gabriel Altay 2007-09-14 52 Debris and Radiation-Induced Damage Effects on EUV Nanolithography Source Collector Mirror Optics Performance CiteSeer...

  10. Radiation-induced esophageal injury: A spectrum from esophagitis to cancer

    SciTech Connect (OSTI)

    Vanagunas, A.; Jacob, P.; Olinger, E. (Northwestern Univ. Medical School, Chicago, IL (USA))

    1990-07-01T23:59:59.000Z

    Radiation esophagitis is a common but frequently unrecognized complication of therapeutic radiation to the neck, chest, or mediastinum. The spectrum of injury ranges from acute self-limited esophagitis to life-threatening esophageal perforation. Complications such as stricture or primary esophageal cancer may occur many years after irradiation, and their linkage to radiation may not be considered. Five cases of radiation-induced injury are described, and the spectrum of radiation-induced esophageal injury is reviewed.

  11. Evaluation of Reaction Rate Theory and Monte Carlo Methods for Application to Radiation-Induced Microstructural Characterization

    SciTech Connect (OSTI)

    Stoller, Roger E [ORNL; Golubov, Stanislav I [ORNL; Becquart, C. S. [Universite de Lille; Domain, C. [EDF R& D, Clamart, France

    2007-08-01T23:59:59.000Z

    The multiscale modeling scheme encompasses models from the atomistic to the continuum scale. Phenomena at the mesoscale are typically simulated using reaction rate theory, Monte Carlo, or phase field models. These mesoscale models are appropriate for application to problems that involve intermediate length scales, and timescales from those characteristic of diffusion to long-term microstructural evolution (~?s to years). Although the rate theory and Monte Carlo models can be used simulate the same phenomena, some of the details are handled quite differently in the two approaches. Models employing the rate theory have been extensively used to describe radiation-induced phenomena such as void swelling and irradiation creep. The primary approximations in such models are time- and spatial averaging of the radiation damage source term, and spatial averaging of the microstructure into an effective medium. Kinetic Monte Carlo models can account for these spatial and temporal correlations; their primary limitation is the computational burden which is related to the size of the simulation cell. A direct comparison of RT and object kinetic MC simulations has been made in the domain of point defect cluster dynamics modeling, which is relevant to the evolution (both nucleation and growth) of radiation-induced defect structures. The primary limitations of the OKMC model are related to computational issues. Even with modern computers, the maximum simulation cell size and the maximum dose (typically much less than 1 dpa) that can be simulated are limited. In contrast, even very detailed RT models can simulate microstructural evolution for doses up 100 dpa or greater in clock times that are relatively short. Within the context of the effective medium, essentially any defect density can be simulated. Overall, the agreement between the two methods is best for irradiation conditions which produce a high density of defects (lower temperature and higher displacement rate), and for materials that have a relatively high density of fixed sinks such as dislocations.

  12. Predictive Models for Regional Hepatic Function Based on 99mTc-IDA SPECT and Local Radiation Dose for Physiologic Adaptive Radiation Therapy

    SciTech Connect (OSTI)

    Wang, Hesheng, E-mail: hesheng@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Feng, Mary [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Frey, Kirk A. [Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Ten Haken, Randall K.; Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Cao, Yue [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Department of Radiology, University of Michigan, Ann Arbor, Michigan (United States); Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan (United States)

    2013-08-01T23:59:59.000Z

    Purpose: High-dose radiation therapy (RT) for intrahepatic cancer is limited by the development of liver injury. This study investigated whether regional hepatic function assessed before and during the course of RT using 99mTc-labeled iminodiacetic acid (IDA) single photon emission computed tomography (SPECT) could predict regional liver function reserve after RT. Methods and Materials: Fourteen patients treated with RT for intrahepatic cancers underwent dynamic 99mTc-IDA SPECT scans before RT, during, and 1 month after completion of RT. Indocyanine green (ICG) tests, a measure of overall liver function, were performed within 1 day of each scan. Three-dimensional volumetric hepatic extraction fraction (HEF) images of the liver were estimated by deconvolution analysis. After coregistration of the CT/SPECT and the treatment planning CT, HEF doseresponse functions during and after RT were generated. The volumetric mean of the HEFs in the whole liver was correlated with ICG clearance time. Three models, dose, priori, and adaptive models, were developed using multivariate linear regression to assess whether the regional HEFs measured before and during RT helped predict regional hepatic function after RT. Results: The mean of the volumetric liver HEFs was significantly correlated with ICG clearance half-life time (r=?0.80, P<.0001), for all time points. Linear correlations between local doses and regional HEFs 1 month after RT were significant in 12 patients. In the priori model, regional HEF after RT was predicted by the planned dose and regional HEF assessed before RT (R=0.71, P<.0001). In the adaptive model, regional HEF after RT was predicted by regional HEF reassessed during RT and the remaining planned local dose (R=0.83, P<.0001). Conclusions: 99mTc-IDA SPECT obtained during RT could be used to assess regional hepatic function and helped predict post-RT regional liver function reserve. This could support individualized adaptive radiation treatment strategies to maximize tumor control and minimize the risk of liver damage.

  13. RADIATION-INDUCED DECOMPOSITION OF U(VI) ALTERATION PHASES OF UO2

    SciTech Connect (OSTI)

    S. Utsunomiya; R.C. Ewing

    2005-09-08T23:59:59.000Z

    U{sup 6+}-phases are common alteration products of spent nuclear fuel under oxidizing conditions, and they may potentially incorporate actinides, such as long-lived {sup 239}Pu and {sup 237}Np, delaying their transport to the biosphere. In order to evaluate the ballistic effects of {alpha}-decay events on the stability of the U{sup 6+}-phases, we report, for the first time, the results of ion beam irradiations (1.0 MeV Kr{sup 2+}) for six different structures of U{sup 6+}-phases: uranophane, kasolite, boltwoodite, saleeite, carnotite, and liebigite. The target uranyl-minerals were characterized by powder X-ray diffraction and identification confirmed by SAED (selected area electron diffraction) in TEM (transmission electron microscopy). The TEM observation revealed no initial contamination of uraninite in these U{sup 6+} phases. All of the samples were irradiated with in situ TEM observation using 1.0 MeV Kr{sup 2+} in the IVEM (intermediate-voltage electron microscope) at the IVEM-Tandem Facility of Argonne National Laboratory. The ion flux was 6.3 x 10{sup 11} ions/cm{sup 2}/sec. The specimen temperatures during irradiation were 298 and 673 K, respectively. The Kr{sup 2+}-irradiation decomposed the U{sup 6+}-phases to nanocrystals of UO{sub 2} at doses as low as 0.006 dpa. The cumulative doses for the pure U{sup 6+}-phases, e.g., uranophane, at 0.1 and 1 million years (m.y.) are calculated to be 0.009 and 0.09 dpa using SRIM2003. However, with the incorporation of 1 wt.% {sup 239}Pu, the calculated doses reach 0.27 and {approx}1.00 dpa in ten thousand and one hundred thousand years, respectively. Under oxidizing conditions, multiple cycles of radiation-induced decomposition to UO{sub 2} followed by alteration to U{sup 6+}-phases should be further investigated to determine the fate of trace elements that may have been incorporated in the U{sup 6+}-phases.

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

    SciTech Connect (OSTI)

    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

    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.

  15. Treatment of Locally Advanced Vaginal Cancer With Radiochemotherapy and Magnetic Resonance Image-Guided Adaptive Brachytherapy: Dose-Volume Parameters and First Clinical Results

    SciTech Connect (OSTI)

    Dimopoulos, Johannes C.A. [Department of Radiation Oncology, Metropolitan Hospital, Athens (Greece); Schmid, Maximilian P., E-mail: maximilian.schmid@akhwien.at [Department of Radiotherapy, Medical University of Vienna, Vienna (Austria); Fidarova, Elena; Berger, Daniel; Kirisits, Christian; Poetter, Richard [Department of Radiotherapy, Medical University of Vienna, Vienna (Austria)

    2012-04-01T23:59:59.000Z

    Purpose: To investigate the clinical feasibility of magnetic resonance image-guided adaptive brachytherapy (IGABT) for patients with locally advanced vaginal cancer and to report treatment outcomes. Methods and Materials: Thirteen patients with vaginal cancer were treated with external beam radiotherapy (45-50.4 Gy) plus IGABT with or without chemotherapy. Distribution of International Federation of Gynecology and Obstetrics stages among patients were as follows: 4 patients had Stage II cancer, 5 patients had Stage III cancer, and 4 patients had Stage IV cancer. The concept of IGABT as developed for cervix cancer was transferred and adapted for vaginal cancer, with corresponding treatment planning and reporting. Doses were converted to the equivalent dose in 2 Gy, applying the linear quadratic model ({alpha}/{beta} = 10 Gy for tumor; {alpha}/{beta} = 3 for organs at risk). Endpoints studied were gross tumor volume (GTV), dose-volume parameters for high-risk clinical target volume (HRCTV), and organs at risk, local control (LC), adverse side effects, and survival. Results: The mean GTV ({+-} 1 standard deviation) at diagnosis was 45.3 ({+-}30) cm{sup 3}, and the mean GTV at brachytherapy was 10 ({+-}14) cm{sup 3}. The mean D90 for the HRCTV was 86 ({+-}13) Gy. The mean D2cc for bladder, urethra, rectum, and sigmoid colon were 80 ({+-}20) Gy, 76 ({+-}16) Gy, 70 ({+-}9) Gy, and 60 ({+-}9) Gy, respectively. After a median follow-up of 43 months (range, 19-87 months), one local recurrence and two distant metastases cases were observed. Actuarial LC and overall survival rates at 3 years were 92% and 85%. One patient with Stage IVA and 1 patient with Stage III disease experienced fistulas (one vesicovaginal, one rectovaginal), and 1 patient developed periurethral necrosis. Conclusions: The concept of IGABT, originally developed for treating cervix cancer, appears to be applicable to vaginal cancer treatment with only minor adaptations. Dose-volume parameters for HRCTV and organs at risk are in a comparable range. First clinical results indicate excellent LC. Further prospective multicenter studies are needed to establish this method and to confirm these results.

  16. Radiation-induced bystander effect and adaptive response in mammalian cells

    E-Print Network [OSTI]

    with cells whose nuclei have been traversed with a single alpha particle each. Pretreatment of cells-induced cancer has traditionally been estimated from cancer incidence among Japanese A-bomb survivors. These data in the absence of definitive data. Both the interna- tional commission on radiation protection (ICRP

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

    SciTech Connect (OSTI)

    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

    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.

  18. Abstract Due to reduction in device feature size and supply voltage, the sensitivity to radiation induced transient faults of

    E-Print Network [OSTI]

    Marculescu, Diana

    , the protection from radiation induced transient faults has become as important as other product characteristics to radiation induced transient faults of digital systems increases dramatically. In this paper, we present two targeting radiation hardening leading up to 80% SER reduction when applied to a subset of ISCAS'89

  19. Debris and Radiation-Induced Damage Effects on EUV Nanolithography Source Collector Mirror Optics Performance

    E-Print Network [OSTI]

    Harilal, S. S.

    Debris and Radiation-Induced Damage Effects on EUV Nanolithography Source Collector Mirror Optics, Argonne, Illinois ABSTRACT Exposure of collector mirrors facing the hot, dense pinch plasma in plasma region of the lamp are known to induce serious damage to nearby collector mirrors. Candidate collector

  20. Repression of ATR pathway by miR-185 enhances radiation-induced apoptosis and proliferation

    E-Print Network [OSTI]

    Cai, Long

    of miR-34a expression may be responsible for important protective mechanisms counteracting radiationOPEN Repression of ATR pathway by miR-185 enhances radiation-induced apoptosis and proliferation of a human microRNA (miRNA), hsa-miR-185, is downregulated in response to ionizing radiation. Elevation of mi

  1. Radiation-induced Genomic Instability and Radiation Sensitivity

    SciTech Connect (OSTI)

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

    2013-01-19T23:59:59.000Z

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

  2. 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 (OSTI)

    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

    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.

  3. The Role of Platelet Factor 4 in Radiation-Induced Thrombocytopenia

    SciTech Connect (OSTI)

    Lambert, Michele P., E-mail: lambertm@email.chop.edu [Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA (United States); Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA (United States); Xiao Liqing; Nguyen, Yvonne [Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA (United States); Kowalska, M. Anna [Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA (United States); Center for Medical Biology, Polish Academy of Science, Lodz (Poland); Poncz, Mortimer [Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA (United States); Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    2011-08-01T23:59:59.000Z

    Purpose: Factors affecting the severity of radiation-induced thrombocytopenia (RIT) are not well described. We address whether platelet factor 4 (PF4; a negative paracrine for megakaryopoiesis) affects platelet recovery postradiation. Methods and Materials: Using conditioned media from irradiated bone marrow (BM) cells from transgenic mice overexpressing human (h) PF4 (hPF4+), megakaryocyte colony formation was assessed in the presence of this conditioned media and PF4 blocking agents. In a model of radiation-induced thrombocytopenia, irradiated mice with varying PF4 expression levels were treated with anti-hPF4 and/or thrombopoietin (TPO), and platelet count recovery and survival were examined. Results: Conditioned media from irradiated BM from hPF4+ mice inhibited megakaryocyte colony formation, suggesting that PF4 is a negative paracrine released in RIT. Blocking with an anti-hPF4 antibody restored colony formation of BM grown in the presence of hPF4+ irradiated media, as did antibodies that block the megakaryocyte receptor for PF4, low-density lipoprotein receptor-related protein 1 (LRP1). Irradiated PF4 knockout mice had higher nadir platelet counts than irradiated hPF4+/knockout litter mates (651 vs. 328 x 106/mcL, p = 0.02) and recovered earlier (15 days vs. 22 days, respectively, p <0.02). When irradiated hPF4+ mice were treated with anti-hPF4 antibody and/or TPO, they showed less severe thrombocytopenia than untreated mice, with improved survival and time to platelet recovery, but no additive effect was seen. Conclusions: Our studies show that in RIT, damaged megakaryocytes release PF4 locally, inhibiting platelet recovery. Blocking PF4 enhances recovery while released PF4 from megakaryocytes limits TPO efficacy, potentially because of increased release of PF4 stimulated by TPO. The clinical value of blocking this negative paracrine pathway post-RIT remains to be determined.

  4. Analysis of Vision Loss Caused by Radiation-Induced Optic Neuropathy After Particle Therapy for Head-and-Neck and Skull-Base Tumors Adjacent to Optic Nerves

    SciTech Connect (OSTI)

    Demizu, Yusuke, E-mail: y_demizu@nifty.co [Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo (Japan); Murakami, Masao; Miyawaki, Daisuke; Niwa, Yasue [Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo (Japan); Akagi, Takashi [Department of Accelerator Managing, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo (Japan); Sasaki, Ryohei [Division of Radiology, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Terashima, Kazuki [Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo (Japan); Suga, Daisaku [Department of Radiation Technology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo (Japan); Kamae, Isao [Division of Medical Statistics, Kobe University Graduate School of Medicine, Kobe, Hyogo (Japan); Hishikawa, Yoshio [Department of Radiology, Hyogo Ion Beam Medical Center, Tatsuno, Hyogo (Japan)

    2009-12-01T23:59:59.000Z

    Purpose: To assess the incident rates of vision loss (VL; based on counting fingers or more severe) caused by radiation-induced optic neuropathy (RION) after particle therapy for tumors adjacent to optic nerves (ONs), and to evaluate factors that may contribute to VL. Methods and Materials: From August 2001 to August 2006, 104 patients with head-and-neck or skull-base tumors adjacent to ONs were treated with carbon ion or proton radiotherapy. Among them, 145 ONs of 75 patients were irradiated and followed for greater than 12 months. The incident rate of VL and the prognostic factors for occurrence of VL were evaluated. The late effects of carbon ion and proton beams were compared on the basis of a biologically effective dose at alpha/beta = 3 gray equivalent (GyE{sub 3}). Results: Eight patients (11%) experienced VL resulting from RION. The onset of VL ranged from 17 to 58 months. The median follow-up was 25 months. No significant difference was observed between the carbon ion and proton beam treatment groups. On univariate analysis, age (>60 years), diabetes mellitus, and maximum dose to the ON (>110 GyE{sub 3}) were significant, whereas on multivariate analysis only diabetes mellitus was found to be significant for VL. Conclusions: The time to the onset of VL was highly variable. There was no statistically significant difference between carbon ion and proton beam treatments over the follow-up period. Based on multivariate analysis, diabetes mellitus correlated with the occurrence of VL. A larger study with longer follow-up is warranted.

  5. Short CommunicationJ. Radiat. Res., 53, 475481 (2012) Triphasic Low-dose Response in Zebrafish Embryos Irradiated by

    E-Print Network [OSTI]

    Yu, K.N.

    2012-01-01T23:59:59.000Z

    the linear no-threshold (LNT) hypothesis for radiation protection considerations, which assumes that the riskShort CommunicationJ. Radiat. Res., 53, 475481 (2012) Triphasic Low-dose Response in Zebrafish, the experimental data were in line with induc- tion of radiation-induced bystander effect as well as rescue effect

  6. Clinical Outcomes of 174 Nasopharyngeal Carcinoma Patients With Radiation-Induced Temporal Lobe Necrosis

    SciTech Connect (OSTI)

    Lam, Tai-Chung, E-mail: lamtaichung@gmail.com [Department of Clinical Oncology, Tuen Mun Hospital (Hong Kong); Wong, Frank C.S. [Department of Clinical Oncology, Tuen Mun Hospital (Hong Kong); Leung, To-Wai [Department of Clinical Oncology, Queen Mary Hospital (Hong Kong); Ng, S.H. [Department of Medicine and Geriatrics, Tuen Mun Hospital (Hong Kong); Tung, Stewart Y. [Department of Clinical Oncology, Tuen Mun Hospital (Hong Kong)

    2012-01-01T23:59:59.000Z

    Purpose: To retrospectively study the clinical outcomes of nasopharyngeal carcinoma patients with radiation-induced temporal lobe necrosis (TLN) treated with steroids, surgery, or observation only. Methods and Patients: We performed a retrospective analysis of 174 consecutive patients diagnosed with TLN between 1990 and 2008. Before 1998, symptomatic patients were treated with oral steroids, while asymptomatic patients were treated conservatively. After 1998, most symptomatic and asymptomatic patients with a large volume of necrosis were treated by intravenously pulsed-steroid therapy with a standardized protocol. We examined factors affecting grade 4 complication-free survival and overall survival. Outcomes of the three treatment groups, those receiving conservative treatment, those receiving oral steroid, and those receiving intravenous pulse steroid, were compared. Results: The mean follow-up time was 115 months. Rates of grade 4 complication-free survival at 2 years and at 5 years after diagnosis of TLN were 72.2% and 54.1%, respectively. The 2-year and 5-year overall survival rates were 57.5% and 35.4%, respectively. Multivariate analysis revealed that being symptomatic at diagnosis (relative risk [RR], 4.5; p = 0.0001), re-irradiation of the nasopharynx (NP) (RR, 1.56; p = 0.008), salvage brachytherapy to the NP (RR, 1.75; p = 0.012), and a short latency period before the diagnosis of TLN (RR, 0.96, p < 0.0001) were independent prognosticators of poor grade 4 complication-free survival. Patients with all four factors had a 100% risk of developing grade 4 complications within 5 years; whereas if no factor was present, the risk was 12.5%. Intravenous pulse steroid therapy was associated with a higher clinical response rate compared with conventional steroid therapy (p < 0.0001); however, it did not affect complication-free survival in multivariate analysis. Conclusions: TLN patients with good prognosticators could be observed without active treatment. Although treatment with intravenously pulsed steroid was associated with better clinical response than conventional steroid delivery, it did not affect the complication-free survival rate of TLN patients.

  7. Radiation Leukemogenesis at Low Dose Rates

    SciTech Connect (OSTI)

    Weil, Michael; Ullrich, Robert

    2013-09-25T23:59:59.000Z

    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.

  8. Radiation-induced gain degradation in lateral PNP BJTs with lightly and heavily doped emitters

    SciTech Connect (OSTI)

    Wu, A. [Univ. of Arizona, Tucson, AZ (United States); Schrimpf, R.D. [Vanderbilt Univ., Nashville, TN (United States); Pease, R.L. [RLP Research, Inc., Albuquerque, NM (United States); Fleetwood, D.M. [Sandia National Labs., Albuquerque, NM (United States); Kosier, S.L. [VTC Inc., Bloomington, MN (United States)

    1997-06-01T23:59:59.000Z

    Ionizing radiation may cause failures in ICs due to gain degradation of individual devices. The base current of irradiated bipolar devices increases with total dose, while the collector current remains relatively constant. This results in a decrease in the current gain. Lateral PNP (LPNP) transistors typically exhibit more degradation than vertical PNP devices at the same total dose, and have been blamed as the cause of early IC failures at low dose rates. It is important to understand the differences in total-dose response between devices with heavily- and lightly-doped emitters in order to compare different technologies and evaluate the applicability of proposed low-dose-rate hardness-assurance methods. This paper addresses these differences by comparing two different LPNP devices from the same process: one with a heavily-doped emitter and one with a lightly-doped emitter. Experimental results demonstrate that the lightly-doped devices are more sensitive to ionizing radiation and simulations illustrate that increased recombination on the emitter side of the junction is responsible for the higher sensitivity.

  9. A prospective study on radiation-induced changes in hearing function

    SciTech Connect (OSTI)

    Herrmann, Franziska [Department of Oto-Rhino-Laryngology, University of Technology-Dresden, Dresden (Germany); Doerr, Wolfgang [Department of Radiotherapy and Radiation Oncology, University of Technology-Dresden, Dresden (Germany); Experimental Center, Medical Faculty Carl Gustav Carus, University of Technology-Dresden, Dresden (Germany); Mueller, Rainer [Department of Oto-Rhino-Laryngology, University of Technology-Dresden, Dresden (Germany); Herrmann, Thomas [Department of Radiotherapy and Radiation Oncology, University of Technology-Dresden, Dresden (Germany)]. E-mail: thomas.herrmann@mailbox.tu-dresden.de

    2006-08-01T23:59:59.000Z

    Purpose: To quantitate changes in hearing function after radiotherapy for head-and-neck tumors. Methods and Materials: At the Department of Radiotherapy and Radiation Oncology, 32 patients were irradiated for head-and-neck tumors. Three-dimensional treatment planning was applied. Total tumor doses were 30.0-77.6 Gy, local doses to the inner ear (n = 64) ranged from 1.7 to 64.3 Gy. Audiometry was performed before the onset of radiotherapy (RT), at a tumor dose of 40 Gy or at the end of palliative treatment, at the end of curative RT, and 2-6 months post-RT. Assays applied were frequency-specific threshold measurements for air and bone conduction, measurements according to Weber and Rinne, tympanometry and assessment of the stapedius reflex. Results: Age and prior disease significantly decreased, whereas previous or concurrent alcohol consumption significantly increased hearing ability. A significant reduction in hearing ability during RT was found for high frequencies (at 40 Gy) and low frequencies (at end of RT), which persisted after RT. No differences were observed for air or bone conduction. None of the other assays displayed time- or dose-dependent changes. Dose-effect analyses revealed an ED50 (dose at which a 50% incidence is expected) for significant changes in hearing thresholds (15 dB) in the range of 20-25 Gy, with large confidence limits. Conclusions: Radiation effects on hearing ability were confined to threshold audiogram values, which started during the treatment without reversibility during 6 months postradiotherapy.

  10. Hyperbaric Oxygen Treatment in Radiation-Induced Cystitis and Proctitis: A Prospective Cohort Study on Patient-Perceived Quality of Recovery

    SciTech Connect (OSTI)

    Oscarsson, Nicklas, E-mail: nicklas.oscarsson@vgregion.se [Department of Anaesthesiology and Intensive Care Medicine, Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg (Sweden); Arnell, Per [Department of Anaesthesiology and Intensive Care Medicine, Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg (Sweden); Lodding, Pr [Department of Urology, Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg (Sweden); Ricksten, Sven-Erik; Seeman-Lodding, Helne [Department of Anaesthesiology and Intensive Care Medicine, Sahlgrenska Academy, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg (Sweden)

    2013-11-15T23:59:59.000Z

    Purpose: In this prospective cohort study, the effects of hyperbaric oxygen treatment (HBOT) were evaluated concerning patient-perceived symptoms of late radiation-induced cystitis and proctitis secondary to radiation therapy for pelvic cancer. Methods and Materials: Thirty-nine patients, 35 men and 4 women with a mean age of 71 (range, 35-84) years were included after informed consent and institutional ethics approval. They had all been treated with radiation therapy for prostate (n=34), cervix (n=2), or rectal (n=3) cancer using external beam radiation at a dose of 25 to 75 Gy. Patients with hematuria requiring blood transfusion were excluded. The HBOT was delivered with 100% oxygen for 90 minutes at 2.0 to 2.4 atmospheres (ATA). Mean number of treatments was 36 (28-40). Symptoms were prospectively assessed using the Expanded Prostate Index Composite score before, during, and 6 to 12 months after HBOT. Results: The HBOT was successfully conducted, and symptoms were alleviated in 76% for patients with radiation cystitis, 89% for patients with radiation proctitis, and 88% of patients with combined cystitis and proctitis. Symptom reduction was demonstrated by an increased Expanded Prostate Index Composite score in the urinary domain from 50 16 to 66 20 after treatment (P<.001) and in the bowel domain from 48 18 to 68 18 after treatment (P<.001). For 31% of the patients with cystitis and 22% with proctitis, there were only trivial symptoms after HBOT. The improvement was sustained at follow-up in both domains 6 to 12 months after HBOT. No severe side effects were observed related to HBOT, and treatment compliance was high. Conclusions: HBOT can be an effective and safe treatment modality for late radiation therapy-induced soft tissue injuries in the pelvic region.

  11. Post Treatment With an FGF Chimeric Growth Factor Enhances Epithelial Cell Proliferation to Improve Recovery From Radiation-Induced Intestinal Damage

    SciTech Connect (OSTI)

    Nakayama, Fumiaki, E-mail: f_naka@nirs.go.j [Department of Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan); Hagiwara, Akiko; Umeda, Sachiko [Department of Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan); Asada, Masahiro; Goto, Megumi; Oki, Junko; Suzuki, Masashi; Imamura, Toru [Signaling Molecules Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan); Akashi, Makoto [Department of Radiation Emergency Medicine, National Institute of Radiological Sciences, Chiba (Japan)

    2010-11-01T23:59:59.000Z

    Purpose: A fibroblast growth factor (FGF) 1-FGF2 chimera (FGFC) was created previously and showed greater structural stability than FGF1. This chimera was capable of stimulating epithelial cell proliferation much more strongly than FGF1 or FGF2 even without heparin. Therefore FGFC was expected to have greater biologic activity in vivo. This study evaluated and compared the protective activity of FGFC and FGF1 against radiation-induced intestinal injuries. Methods and Materials: We administered FGFC and FGF1 intraperitoneally to BALB/c mice 24 h before or after total-body irradiation (TBI). The numbers of surviving crypts were determined 3.5 days after TBI with gamma rays at doses ranging from 8 to 12 Gy. Results: The effect of FGFC was equal to or slightly superior to FGF1 with heparin. However, FGFC was significantly more effective in promoting crypt survival than FGF1 (p < 0.01) when 10 {mu}g of each FGF was administered without heparin before irradiation. In addition, FGFC was significantly more effective at promoting crypt survival (p < 0.05) than FGF1 even when administered without heparin at 24 h after TBI at 10, 11, or 12 Gy. We found that FGFC post treatment significantly promoted 5-bromo-2'-deoxyuridine incorporation into crypts and increased crypt depth, resulting in more epithelial differentiation. However, the number of apoptotic cells in FGFC-treated mice decreased to almost the same level as that in FGF1-treated mice. Conclusions: These findings suggest that FGFC strongly enhanced radioprotection with the induction of epithelial proliferation without exogenous heparin after irradiation and is useful in clinical applications for both the prevention and post treatment of radiation injuries.

  12. 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 (OSTI)

    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

    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.

  13. Reduction in radiation-induced brain injury by use of pentobarbital or lidocaine protection

    SciTech Connect (OSTI)

    Oldfield, E.H.; Friedman, R.; Kinsella, T.; Moquin, R.; Olson, J.J.; Orr, K.; DeLuca, A.M. (National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD (USA))

    1990-05-01T23:59:59.000Z

    To determine if barbiturates would protect brain at high doses of radiation, survival rates in rats that received whole-brain x-irradiation during pentobarbital- or lidocaine-induced anesthesia were compared with those of control animals that received no medication and of animals anesthetized with ketamine. The animals were shielded so that respiratory and digestive tissues would not be damaged by the radiation. Survival rates in rats that received whole-brain irradiation as a single 7500-rad dose under pentobarbital- or lidocaine-induced anesthesia was increased from between from 0% and 20% to between 45% and 69% over the 40 days of observation compared with the other two groups (p less than 0.007). Ketamine anesthesia provided no protection. There were no notable differential effects upon non-neural tissues, suggesting that pentobarbital afforded protection through modulation of ambient neural activity during radiation exposure. Neural suppression during high-dose cranial irradiation protects brain from acute and early delayed radiation injury. Further development and application of this knowledge may reduce the incidence of radiation toxicity of the central nervous system (CNS) and may permit the safe use of otherwise unsafe doses of radiation in patients with CNS neoplasms.

  14. Radiation hardening and radiation-induced chromium depletion effects on intergranular stress corrosion cracking of austenitic stainless steels

    SciTech Connect (OSTI)

    Bruemmer, S.M.; Simonen, E.P.

    1993-03-01T23:59:59.000Z

    Available data on neutron-irradiated materials have been analyzed and correlations developed between fluence, yield strength, grain boundary chromium concentration and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in critical fluence (0.2 to 2.5 n/cm[sup 2]) for IGSCC are documented.In many cases, this variability is consistent with yield strength differences among irradiated materials. IGSCC correlated better to yield strength than to fluence for most heats suggesting a possible role of the radiation-induced hardening (and microstructure) on cracking. However, isolatedheats reveal a wide range of yield strengths from 450 to 800 MPa necessary to promote IGSCC which cannot be understood by strength effects alone. Grain boundary Cr depletion explain differences in IGSCC susceptibility for irradiated stainless steels. Cr contents versus SCC shows that all materials showing IG cracking have some grain boundary depletion ([ge]2%). Grain boundary Cr concentrations for cracking (below [approximately]16 wt %) are in good agreement with similar SCC tests on unirradiated 304 SS with controlled depletion profiles. Heats that prompt variability in the yield strength correlation, are accounted for bydifferences in their interfacial Cr contents. Certain stainless steels are more resistant to cracking even though they have significant radiation-induced Cr depletion. It is proposed that Cr depletion is required for IASCC, but observed susceptibility is modified by other microchemical and microstructural components.

  15. Radiation hardening and radiation-induced chromium depletion effects on intergranular stress corrosion cracking of austenitic stainless steels

    SciTech Connect (OSTI)

    Bruemmer, S.M.; Simonen, E.P.

    1993-03-01T23:59:59.000Z

    Available data on neutron-irradiated materials have been analyzed and correlations developed between fluence, yield strength, grain boundary chromium concentration and cracking susceptibility in high-temperature water environments. Large heat-to-heat differences in critical fluence (0.2 to 2.5 n/cm{sup 2}) for IGSCC are documented.In many cases, this variability is consistent with yield strength differences among irradiated materials. IGSCC correlated better to yield strength than to fluence for most heats suggesting a possible role of the radiation-induced hardening (and microstructure) on cracking. However, isolatedheats reveal a wide range of yield strengths from 450 to 800 MPa necessary to promote IGSCC which cannot be understood by strength effects alone. Grain boundary Cr depletion explain differences in IGSCC susceptibility for irradiated stainless steels. Cr contents versus SCC shows that all materials showing IG cracking have some grain boundary depletion ({ge}2%). Grain boundary Cr concentrations for cracking (below {approximately}16 wt %) are in good agreement with similar SCC tests on unirradiated 304 SS with controlled depletion profiles. Heats that prompt variability in the yield strength correlation, are accounted for bydifferences in their interfacial Cr contents. Certain stainless steels are more resistant to cracking even though they have significant radiation-induced Cr depletion. It is proposed that Cr depletion is required for IASCC, but observed susceptibility is modified by other microchemical and microstructural components.

  16. Long-Term Follow-Up of Dose-Adapted and Reduced-Field Radiotherapy With or Without Chemotherapy for Central Nervous System Germinoma

    SciTech Connect (OSTI)

    Jensen, Ashley W. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Issa Laack, Nadia N., E-mail: laack.nadia@mayo.ed [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Buckner, Jan C. [Department of Oncology, Mayo Clinic, Rochester, MN (United States); Schomberg, Paula J. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States); Wetmore, Cynthia J. [Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN (United States); Brown, Paul D. [Department of Radiation Oncology, Mayo Clinic, Rochester, MN (United States)

    2010-08-01T23:59:59.000Z

    Purpose: To update our institutional experience with neoadjuvant chemotherapy and minimized radiotherapy vs. radiation monotherapy for intracranial germinoma. Methods and Materials: We retrospectively reviewed records of 59 patients with diagnosis of primary intracranial germinoma between 1977 and 2007. Treatment was irradiation alone or neoadjuvant platinum-based chemotherapy and local irradiation (initial tumor plus margin) for patients with localized complete response and reduced-dose craniospinal irradiation for others. Results: For the chemoradiotherapy group (n = 28), median follow-up was 7 years. No patient died. The freedom from progression (FFP) rate was 88% at 5 years and 80% at 10 years. In 4 patients, disease recurred 1.1 to 6.8 years after diagnosis. All were young male patients who received 30.6 Gy to local fields after complete response to chemotherapy. The FFP rate was 88% for local irradiation vs. 100% for more extensive fields (p = .06). For the radiotherapy-alone group (n = 31), median follow-up was 15 years. Overall and disease-free survival rates were 93% and 93% at 5 years and 90% and 87% at 15 years. In 5 patients, disease recurred 1.1 to 4.9 years after diagnosis. Most patients in this group were young men 18 to 23 years of age with suprasellar primary disease treated with about 50 Gy to local fields. The FFP rate was 44% for local irradiation vs. 100% for more extensive fields (p < .01). Conclusions: The addition of neoadjuvant chemotherapy to local-field radiotherapy reduced central nervous system cancer recurrence when high-risk patients were excluded by thorough pretreatment staging. There was trend toward improved central nervous system tumor control when larger fields (whole brain, whole ventricle, or craniospinal axis) were used.

  17. Low Dose IR Creates an Oncogenic Microenvironment by Inducing Premature

    SciTech Connect (OSTI)

    Yuan, Zhi-Min [Harvard School of Public Health

    2013-04-28T23:59:59.000Z

    Introduction Much of the work addressing ionizing radiation-induced cellular response has been carried out mainly with the traditional cell culture technique involving only one cell type, how cellular response to IR is influenced by the tissue microenvironment remains elusive. By use of a three-dimensional (3D) co-culture system to model critical interactions of different cell types with their neighbors and with their environment, we recently showed that low-dose IR-induced extracellular signaling via the tissue environment affects profoundly cellular responses. This proposal aims at determining the response of mammary epithelial cells in a tissue-like setting.

  18. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy?

    SciTech Connect (OSTI)

    Janssens, K.; Adams, F. [Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry; Rivers, M.L.; Jones, K.W. [Brookhaven National Lab., Upton, NY (United States)

    1992-10-01T23:59:59.000Z

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ({mu}-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed.

  19. Synchrotron radiation induced x-ray micro analysis: A realistic alternative for electron- and ion beam microscopy

    SciTech Connect (OSTI)

    Janssens, K.; Adams, F. (Universitaire Instelling Antwerpen, Antwerp (Belgium). Dept. of Chemistry); Rivers, M.L.; Jones, K.W. (Brookhaven National Lab., Upton, NY (United States))

    1992-01-01T23:59:59.000Z

    Synchrotron Radiation induced X-ray micro Fluorescence analysis ([mu]-SRXRF) is compared with more conventional microanalytical techniques such as Secondary Ion Microscopy (SIMS) and Electron Probe X-ray Microanalysis (EPXMA) for two typical microanalytical applications. SRXRF and EPXMA are employed for the analysis of individual particles, showing the complementary character of both techniques. By means of element mapping of trace constituents in a heterogeneous feldspar, the strong and weak points of SRXRF in comparison to EPXMA and SIMS are illustrated. The most striking difference between SRXRF and the other two microanalytical methods is the ability of SRXRF to probe deep into the investigated Material, whereas SIMS and EPXMA only investigate the upper surface of the material. The possibilities of SRXRF at third generation synchrotron rings is also briefly discussed.

  20. The Relationship between Organ Dose and Patients Size in Multidetector Computed Tomography (MDCT) Scans Utilizing Tube Current Modulation (TCM)

    E-Print Network [OSTI]

    Khatonabadi, Maryam

    2013-01-01T23:59:59.000Z

    Dose Reduction With Chest Computed Tomography Using AdaptiveDose reduction in computed tomography by attenuation-baseddose from cardiac computed tomography before and after

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

    SciTech Connect (OSTI)

    Not Available

    1987-01-01T23:59:59.000Z

    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.

  2. Radiation-Induced Alterations in Mouse Brain Development Characterized by Magnetic Resonance Imaging

    SciTech Connect (OSTI)

    Gazdzinski, Lisa M.; Cormier, Kyle [Mouse Imaging Centre, Hospital for Sick Children, Toronto (Canada)] [Mouse Imaging Centre, Hospital for Sick Children, Toronto (Canada); Lu, Fred G. [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto (Canada)] [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto (Canada); Lerch, Jason P. [Mouse Imaging Centre, Hospital for Sick Children, Toronto (Canada) [Mouse Imaging Centre, Hospital for Sick Children, Toronto (Canada); Department of Medical Biophysics, University of Toronto, Toronto (Canada); Wong, C. Shun [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto (Canada) [Department of Radiation Oncology, Sunnybrook Health Sciences Centre, Toronto (Canada); Department of Medical Biophysics, University of Toronto, Toronto (Canada); Department of Radiation Oncology, University of Toronto, Toronto (Canada); Nieman, Brian J., E-mail: bjnieman@phenogenomics.ca [Mouse Imaging Centre, Hospital for Sick Children, Toronto (Canada); Department of Medical Biophysics, University of Toronto, Toronto (Canada)

    2012-12-01T23:59:59.000Z

    Purpose: The purpose of this study was to identify regions of altered development in the mouse brain after cranial irradiation using longitudinal magnetic resonance imaging (MRI). Methods and Materials: Female C57Bl/6 mice received a whole-brain radiation dose of 7 Gy at an infant-equivalent age of 2.5 weeks. MRI was performed before irradiation and at 3 time points following irradiation. Deformation-based morphometry was used to quantify volume and growth rate changes following irradiation. Results: Widespread developmental deficits were observed in both white and gray matter regions following irradiation. Most of the affected brain regions suffered an initial volume deficit followed by growth at a normal rate, remaining smaller in irradiated brains compared with controls at all time points examined. The one exception was the olfactory bulb, which in addition to an early volume deficit, grew at a slower rate thereafter, resulting in a progressive volume deficit relative to controls. Immunohistochemical assessment revealed demyelination in white matter and loss of neural progenitor cells in the subgranular zone of the dentate gyrus and subventricular zone. Conclusions: MRI can detect regional differences in neuroanatomy and brain growth after whole-brain irradiation in the developing mouse. Developmental deficits in neuroanatomy persist, or even progress, and may serve as useful markers of late effects in mouse models. The high-throughput evaluation of brain development enabled by these methods may allow testing of strategies to mitigate late effects after pediatric cranial irradiation.

  3. Dose-dependent misrejoining of radiation-induced DNA double-strand breaks in human fibroblasts: Experimental and theoretical study for high and low LET radiation

    E-Print Network [OSTI]

    Rydberg, Bjorn; Cooper, Brian; Cooper, Priscilla K.; Holley, William; Chatterjee, Aloke

    2004-01-01T23:59:59.000Z

    S. Kim, and R. M. Myers. Radiation hybrid mapping: a somaticformulation of dual radiation action. Radiat. Res. 75: 471-High-Linear Energy Transfer Radiation in Human Fibroblasts.

  4. Nuclear apoJ: A low dose radiation inducible regulator of cell death. Final report for period September 15, 1998 - September 14, 2001

    SciTech Connect (OSTI)

    Aronow, Bruce J.

    2002-04-19T23:59:59.000Z

    This project was based on preliminary data that was published by Dr. Boothman (Yang et al. 2000) which indicated a strong induction of apoJ gene expression, increased secretion of the protein, and accumulation of an apparently somewhat different form of the apoJ protein in the nucleus of MCF-7 breast carcinoma cells undergoing response to DNA damage. A clone expressing apoJ protein was isolated that was capable of interacting with Ku80, a component of the double strand break repair complex that is essential for the successful repair of rearranging immunoglobulin and T-cell receptor genes as evidenced by failure to produce mature B and T cells in the absence of Ku70. ApoJ clones isolated and characterized by Dr. Boothman bound strongly to a Ku-70 ''bait'' protein. Over-expression of these same clones in a cell line was capable of killing the cell. ApoJ is very strongly induced in many instances of programmed cell death and has been proposed repeatedly to play some sort of effector role in the process. Our principle hypothesis for this study was that the strong induction of the apoJ gene and the particular expression of a nuclear form of the protein was potentially a causal factor in the decision point made by the cell as it attempts to repair double-strand breakage based DNA damage. The hypothesis was that if sufficiently high damage occurred, it would be deleterious to maintain the cell's viability through continued DNA repair. One method to inhibit DNA repair might be by inhibiting proteins such as Ku-70 that are necessary for double-strand break repair. If apoJ does play a critical role in tipping the decision balance over to cell death, we reasoned that deficiency of apoJ would cause increased accumulation of cells with DNA damage and that this might decrease cell death in response to DNA damage and increase tumor occurrence rates. To test this hypothesis and its potential implications, we exposed wildtype and apoJ deficient animals that we constructed through gene targeting to increasing levels of ionizing radiation from a Cesium source. Data gathered under the support of this grant application initially indicated that apoJ deficient animals were more resistant to radiation, but as we accumulated more and more data points and covered a tighter exposure range, the genotype-based differences became insignificant. However, the possibility existed that because mortality based radiation-resistance could be attributable to mechanism for which nuclear apoJ was not rate determining, we maintained a very large of colony of apoJ knockout and wildtype animals in both the C57/B16 and Cv129 strain backgrounds that were exposed to sub-lethal levels of ionizing radiation to monitor for the occurrence of tumors. These animals were allowed to fully recover and age normally in either germ free or normal animal housing. Our results demonstrated no significant differences between wildtype and apoJ knockout animals over a period that extended up to 30 months for individual animals. We recorded similar weight gain, a relatively low mortality rate, and a similar mixture and rate of sarcoma and adenocarcinomas after surviving the initial ionizing radiation exposures. Thus we conclude that apoJ gene function, which was totally eliminated by our gene targeting, did not influence radiation sensitivity or serve as a tumor suppressor in response to DNA damage.

  5. Molecular analysis of radiation-induced albino (c)-locus mutations that cause death at preimplantation stages of development

    SciTech Connect (OSTI)

    Rinchik, E.M. (Oak Ridge National Lab., TN (United States)); Toenjes, R.R.; Paul, D. (Fraunhofer-Instituet fuer Toxikologie und Aerosolforschung, Hannover (Germany)); Potter, M.D. (Univ. of Tenn.-Oak Ridge Graduate School of Biomedical Sciences, Oak Ridge, TN (United States))

    1993-12-01T23:59:59.000Z

    Deletion mutations at the albino (c) locus have been useful for continuing the development of fine-structure physical and functional maps of the Fes-Hbb region of mouse chromosome 7. This report describes the molecular analysis of a number of radiation-induced c deletions that, when homozygous, cause death of the embryo during preimplantation stages. The distal extent of these deletions defines a locus, pid, (preimplantation development) genetically associated with this phenotype. The proximal breakpoints of eight of these deletions were mapped with respect to the Tyr (tyrosinase; albino) gene as well as to anonymous loci within the Fah-Tyr region that are defined by the Pmv-31 viral integration site and by chromosome-microdissection clones. Rearrangements corresponding to the proximal breakpoints of two of these deletions were detected by Southern blot analysis, and a size-altered restriction fragment carrying the breakpoint of one of them was cloned. A probe derived from this deletion fusion fragment defines a locus, D7Rn6, which maps within (or distal to) the pid region, and which discriminates among the distal extents of deletions eliciting the pid phenotype. Extension of physical maps from D7Rn6 should provide access both to the pid region and to loci mapping distal to pid that are defined by N-ethyl-N-nitrosourea-induced lethal mutations. 36 refs., 10 figs.

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

    SciTech Connect (OSTI)

    Scott, Bobby, R., Ph.D.

    2003-06-27T23:59:59.000Z

    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

  7. Radiation Dose-Volume Effects in the Stomach and Small Bowel

    SciTech Connect (OSTI)

    Kavanagh, Brian D., E-mail: Brian.Kavanagh@ucdenver.ed [Department of Radiation Oncology, University of Colorado-Denver School of Medicine, Aurora, CO (United States); Pan, Charlie C. [Department of Radiation Oncology, University of Michigan Medical School, Ann Arbor, MI (United States); Dawson, Laura A. [Department of Radiation Oncology, Princess Margaret Hospital, University of Toronto, Toronto, ON (Canada); Das, Shiva K. [Department of Radiation Oncology, Duke University Medical Center, Durham, NC (United States); Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Ten Haken, Randall K.; Miften, Moyed [Department of Radiation Oncology, University of Colorado-Denver School of Medicine, Aurora, CO (United States)

    2010-03-01T23:59:59.000Z

    Published data suggest that the risk of moderately severe (>=Grade 3) radiation-induced acute small-bowel toxicity can be predicted with a threshold model whereby for a given dose level, D, if the volume receiving that dose or greater (VD) exceeds a threshold quantity, the risk of toxicity escalates. Estimates of VD depend on the means of structure segmenting (e.g., V15 = 120 cc if individual bowel loops are outlined or V45 = 195 cc if entire peritoneal potential space of bowel is outlined). A similar predictive model of acute toxicity is not available for stomach. Late small-bowel/stomach toxicity is likely related to maximum dose and/or volume threshold parameters qualitatively similar to those related to acute toxicity risk. Concurrent chemotherapy has been associated with a higher risk of acute toxicity, and a history of abdominal surgery has been associated with a higher risk of late toxicity.

  8. Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivity

    SciTech Connect (OSTI)

    Kleiman, Norman Jay [Columbia University] [Columbia University

    2013-11-30T23:59:59.000Z

    The lens of the eye is one of the most radiosensitive tissues in the body. Ocular ionizing radiation exposure results in characteristic, dose related, progressive lens changes leading to cataract formation. While initial, early stages of lens opacification may not cause visual disability, the severity of such changes progressively increases with dose until vision is impaired and cataract extraction surgery may be required. Because of the transparency of the eye, radiation induced lens changes can easily be followed non-invasively over time. Thus, the lens provides a unique model system in which to study the effects of low dose ionizing radiation exposure in a complex, highly organized tissue. Despite this observation, considerable uncertainties remain surrounding the relationship between dose and risk of developing radiation cataract. For example, a growing number of human epidemiological findings suggest significant risk among various groups of occupationally and accidentally exposed individuals and confidence intervals that include zero dose. Nevertheless, questions remain concerning the relationship between lens opacities, visual disability, clinical cataract, threshold dose and/or the role of genetics in determining radiosensitivity. Experimentally, the response of the rodent eye to radiation is quite similar to that in humans and thus animal studies are well suited to examine the relationship between radiation exposure, genetic determinants of radiosensitivity and cataractogenesis. The current work has expanded our knowledge of the low-dose effects of X-irradiation or high-LET heavy ion exposure on timing and progression of radiation cataract and has provided new information on the genetic, molecular, biochemical and cell biological features which contribute to this pathology. Furthermore, findings have indicated that single and/or multiple haploinsufficiency for various genes involved in DNA repair and cell cycle checkpoint control, such as Atm, Brca1 or Rad9, influence cataract development and thus radiosensitivity. These observations have direct applicability to various human populations including accidentally exposed individuals, interventional medical workers, astronauts and nuclear plant workers.

  9. Non-Targeted Effects Induced by Ionizing Radiation: Mechanisms and Potential Impact on Radiation Induced Health Effects

    SciTech Connect (OSTI)

    Morgan, William F.; Sowa, Marianne B.

    2015-01-01T23:59:59.000Z

    Not-targeted effects represent a paradigm shift from the "DNA centric" view that ionizing radiation only elicits biological effects and subsequent health consequences as a result of an energy deposition event in the cell nucleus. While this is likely true at higher radiation doses (> 1Gy), at low doses (< 100mGy) non-targeted effects associated with radiation exposure might play a significant role. Here definitions of non-targeted effects are presented, the potential mechanisms for the communication of signals and signaling networks from irradiated cells/tissues are proposed, and the various effects of this intra- and intercellular signaling are described. We conclude with speculation on how these observations might lead to and impact long-term human health outcomes.

  10. SU-E-J-65: Evaluation of a Radiation-Induced Cell Proliferation Probability Formula Using Monte Carlo Simulation

    SciTech Connect (OSTI)

    Watanabe, Y; Dahlman, E [University of Minnesota, Minneapolis, MN (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To evaluate the analytic formula of the cell death probability after single fraction dose. Methods: Cancer cells endlessly divide, but radiation causes the cancer cells to die. Not all cells die right away after irradiation. Instead, they continue dividing for next few cell cycles before they stop dividing and die. At the end of every cell cycle, the cell decides if it undertakes the mitotic process with a certain probability, Pdiv, which is altered by the radiation. Previously, by using a simple analytic model of radiobiology experiments, we obtained a formula of Pdeath (= 1 ? Pdiv). A question is if the proposed probability can reproduce the well-known survival data of the LQ model. In this study, we evaluated the formula by doing a Monte Carlo simulation of the cell proliferation process. Starting with Ns seed cells, the cell proliferation process was simulated for N generations or until all cells die. We counted the number of living cells at the end. Assuming that the cell colony survived when more than Nc cells were still alive, the surviving fraction S was estimated. We compared the S vs. dose, or S-D curve, with the LQ model. Results: The results indicated that our formula does not reproduce the experimentally observed S-D curve without selecting appropriate ? and ?/?. With parameter optimization, there was a fair agreement between the MC result and the LQ curve of dose lower than 20Gy. However, the survival fraction of MC decreased much faster in comparison to the LQ data for doses higher than 20 Gy. Conclusion: This study showed that the previously derived probability of cell death per cell cycle is not sufficiently accurate to replicate common radiobiological experiments. The formula must be modified by considering its cell cycle dependence and some other unknown effects.

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

    SciTech Connect (OSTI)

    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

    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.

  12. Adaptation Plan

    E-Print Network [OSTI]

    Durnbaugh, A.

    2011-01-01T23:59:59.000Z

    ? Built Environment ? Natural Environment ? People FIVE STRATEGIES Copyright 2011, City of Chicago ADAPTATION ESL-KT-11-11-16 9 CCAP Adaptation Evolution 2007 2008 2009 2010 ? Understood the climate science: Assess climate impacts... E xi st in g Tr un k Existing on Rogers Rogers Ave CIP Stormwater management: Chicago?s comprehensive sewer model Climate impacts Example actions to prepare the built environment Copyright 2011, City of Chicago ESL-KT-11-11-16 13 CCAP...

  13. Low Dose Suppression of Neoplastic Transformation in Vitro

    SciTech Connect (OSTI)

    John Leslie Redpath

    2012-05-01T23:59:59.000Z

    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.

  14. SCIENTIFIC CORRESPONDENCE Radiation doses

    E-Print Network [OSTI]

    Shlyakhter, Ilya

    -- ation doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk

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

    SciTech Connect (OSTI)

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

    2007-01-23T23:59:59.000Z

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

  16. Neutron dose equivalent meter

    DOE Patents [OSTI]

    Olsher, Richard H. (Los Alamos, NM); Hsu, Hsiao-Hua (Los Alamos, NM); Casson, William H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM); Kleck, Jeffrey H. (Menlo Park, CA); Beverding, Anthony (Foster City, CA)

    1996-01-01T23:59:59.000Z

    A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

  17. Adaptation Plan

    E-Print Network [OSTI]

    Durnbaugh, A.

    2011-01-01T23:59:59.000Z

    /pest introduction. Buildings Fa?ade & structural damage. Higher peak electricity demand. Lake Michigan Decreased lake ice in winter & lower lake levels. Greater stress on water resources in times of need. Homes Increased cooling costs & energy... of Chicago ? 2011 ESL-KT-11-11-16 3 Chicago River Promote & incentivize green infrastructure to manage stormwater. Monitor threat of aquatic invasive species. RESILIENCY Adaptation will help reduce the impact of the changes that can be expected...

  18. Estimate of Radiation-Induced Steel Embrittlement in the BWR Core Shroud and Vessel Wall from Reactor-Grade MOX/UOX Fuel for the Nuclear Power Plant at Laguna Verde, Veracruz, Mexico

    SciTech Connect (OSTI)

    Vickers, Lisa R. [BWXT, U.S. Department of Energy, Pantex Plant, P.O. Box 30020, Hwy 60/FM 2373, Amarillo, TX 79120-0020 (United States)

    2002-07-01T23:59:59.000Z

    The government of Mexico has expressed interest to utilize the Laguna Verde boiling water reactor (BWR) nuclear power plant for the disposition of reprocessed spent uranium oxide (UOX) fuel in the form of reactor-grade mixed oxide (MOX) fuel. MOX fuel would replace spent UOX fuel as a fraction in the core from 18 - 30% depending on the fuel loading cycle. MOX fuel is expected to increase the neutron fluence, flux, fuel centerline temperature, reactor core pressure, and yield higher energy neutrons. There is concern that a core with a fraction of MOX fuel (i.e., increased {sup 239}Pu wt%) would increase the radiation-induced steel embrittlement within the core shroud and vessel wall as compared to only conventional, enriched UOX fuel in the core. The evaluation of radiation-induced steel embrittlement within the core shroud and vessel wall is a concern because of the potentially adverse affect to personnel and public safety, environment, and operating life of the reactor. The primary conclusion of this research was that the addition of the maximum fraction of 1/3 MOX fuel to the LV1 BWR core did significantly accelerate the radiation-induced steel embrittlement such that without mitigation of steel embrittlement by periodic thermal annealing or reduction in operating parameters such as, neutron fluence, core temperature and pressure, it posed a potentially adverse affect to the personnel and public safety, environment, and operating life of the reactor. (author)

  19. SNP in TXNRD2 Associated With Radiation-Induced Fibrosis: A Study of Genetic Variation in Reactive Oxygen Species Metabolism and Signaling

    SciTech Connect (OSTI)

    Edvardsen, Hege, E-mail: hege.edvardsen@rr-research.no [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway) [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway); K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway); Landmark-Hyvik, Hege [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway) [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway); K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway); Reinertsen, Kristin V. [National Resource Centre for Late Effects after Cancer Treatment, OUS Radiumhospitalet, Oslo (Norway)] [National Resource Centre for Late Effects after Cancer Treatment, OUS Radiumhospitalet, Oslo (Norway); Zhao, Xi [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway) [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway); K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway); Grenaker-Alns, Grethe Irene; Nebdal, Daniel [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway)] [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway); Syvnen, Ann-Christine [Department of Medical Sciences, Uppsala University, Uppsala (Sweden)] [Department of Medical Sciences, Uppsala University, Uppsala (Sweden); Rdningen, Olaug [Department of Medical Genetics, OUS Ullevaal, Oslo (Norway)] [Department of Medical Genetics, OUS Ullevaal, Oslo (Norway); Alsner, Jan; Overgaard, Jens [Department of Experimental Clinical Oncology, Ahus University Hospital (Norway)] [Department of Experimental Clinical Oncology, Ahus University Hospital (Norway); Borresen-Dale, Anne-Lise [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway) [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway); K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway); Foss, Sophie D. [K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway) [K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway); National Resource Centre for Late Effects after Cancer Treatment, OUS Radiumhospitalet, Oslo (Norway); Kristensen, Vessela N. [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway) [Department of Genetics, Institute for Cancer Research, OUS Radiumhospitalet, Oslo (Norway); K. G. Jebsen Breast cancer centre, Institute for Clinical Medicine, University of Oslo, Oslo (Norway); Department of Clinical Molecular Biology (EpiGen), Division of Medicine, Ahus University Hospital (Norway)

    2013-07-15T23:59:59.000Z

    Purpose: The aim of the study was to identify noninvasive markers of treatment-induced side effects. Reactive oxygen species (ROS) are generated after irradiation, and genetic variation in genes related to ROS metabolism might influence the level of radiation-induced adverse effects (AEs). Methods and Materials: 92 breast cancer (BC) survivors previously treated with hypofractionated radiation therapy were assessed for the AEs subcutaneous atrophy and fibrosis, costal fractures, lung fibrosis, pleural thickening, and telangiectasias (median follow-up time 17.1 years). Single-nucleotide polymorphisms (SNPs) in 203 genes were analyzed for association to AE grade. SNPs associated with subcutaneous fibrosis were validated in an independent BC survivor material (n=283). The influence of the studied genetic variation on messenger ribonucleic acid (mRNA) expression level of 18 genes previously associated with fibrosis was assessed in fibroblast cell lines from BC patients. Results: Subcutaneous fibrosis and atrophy had the highest correlation (r=0.76) of all assessed AEs. The nonsynonymous SNP rs1139793 in TXNRD2 was associated with grade of subcutaneous fibrosis, the reference T-allele being more prevalent in the group experiencing severe levels of fibrosis. This was confirmed in another sample cohort of 283 BC survivors, and rs1139793 was found significantly associated with mRNA expression level of TXNRD2 in blood. Genetic variation in 24 ROS-related genes, including EGFR, CENPE, APEX1, and GSTP1, was associated with mRNA expression of 14 genes previously linked to fibrosis (P?.005). Conclusion: Development of subcutaneous fibrosis can be associated with genetic variation in the mitochondrial enzyme TXNRD2, critically involved in removal of ROS, and maintenance of the intracellular redox balance.

  20. Evaluation of Radiation Dose Effects on Rat Bones Using Synchrotron Radiation Computed Microtomography

    SciTech Connect (OSTI)

    Nogueira, Liebert Parreiras; Braz, Delson [Nuclear Instrumentation Laboratory / COPPE / UFRJ, P.O. Box 68509, 21945-970, Rio de Janeiro (Brazil); Barroso, Regina Cely [Physics Institute / State University of Rio de Janeiro, 20550-900, Rio de Janeiro (Brazil); Almeida, Carlos Eduardo de; Andrade, Cherley Borba [Laboratory of Radiological Sciences / State University of Rio de Janeiro, Rio de Janeiro (Brazil); Tromba, Giuliana [Sincrotrone Trieste SCpA, Strada Statale S.S. 14 km 163.5, 34012 Basovizza, Trieste (Italy)

    2011-12-13T23:59:59.000Z

    In this work, we investigated the consequences of irradiation in the femora and ribs of rats submitted to radiation doses of 5 Gy. Three different sites in femur specimens (head, distal metaphysis and distal epiphysis) and one in ribs (ventral) were imaged using synchrotron radiation microcomputed tomography to assess trabecular bone microarchitecture. Histomorphometric quantification was calculated directly from the 3D microtomographic images using synchrotron radiation. The 3D microtomographic images were obtained at the SYRMEP (SYnchrotron Radiation for MEdical Physics) beamline at the Elettra Synchrotron Laboratory in Trieste, Italy. A better understanding of the biological interactions that occur after exposure to photon radiation is needed in order to optimize therapeutic regimens and facilitate development and strategies that decrease radiation-induced side effects in humans. Results showed significant differences between irradiated and non-irradiated specimens, mostly in head and distal metaphysis bone sites.

  1. Penile bulb dose and impotence after three-dimensional conformal radiotherapy for prostate cancer on RTOG 9406: Findings from a prospective, multi-institutional, phase I/II dose-escalation study

    SciTech Connect (OSTI)

    Roach, Mack [University of California San Francisco, San Francisco, CA (United States)]. E-mail: roach@radonc17.ucsf.edu; Winter, Kathryn [Radiation Therapy Oncology Group, Philadelphia, PA (United States); Michalski, Jeffrey M. [Washington University, St. Louis, MO (United States); Cox, James D. [3D Quality Assurance Center at Washington University St. Louis, MO (United States); Purdy, James A. [University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Bosch, Walter [University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Lin Xiao [University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Shipley, William S. [Massachusetts General Hospital, Boston MA (United States)

    2004-12-01T23:59:59.000Z

    Purpose: To assess the relationship between the dose to the bulb of the penis and the risk of impotence in men treated on Radiation Therapy Oncology Group (RTOG) 9406. Methods and materials: Men enrolled on a Phase I/II dose-escalation study, RTOG 9406, who were reported to be potent at entry and evaluable (n = 158) were selected for inclusion. Follow-up evaluations were scheduled every 3, 4, and 6 months for the first, second, and the third through fifth years, then annually. At each follow-up visit an assessment of potency status was made. Penile structures were defined by a single observer blinded to the potency status, using Web-based, on-line software. The dosimetry for penile structures was calculated at the Quality Assurance Center at Washington University and provided to RTOG Statistical Headquarters to determine whether there was a relationship between dose and impotence. Results: Patients whose median penile dose was {>=}52.5 Gy had a greater risk of impotence compared with those receiving <52.5 Gy (p = 0.039). In a multivariate analysis neither age, the dose to the prostate, nor the use of hormonal therapy correlated with the risk of impotence. Conclusions: Dose to the bulb of the penis seems to be associated with the risk of radiation-induced impotence.

  2. Radiation-induced lung injury

    SciTech Connect (OSTI)

    Rosiello, R.A.; Merrill, W.W. (Yale Univ. Medical Center, New Haven, CT (USA))

    1990-03-01T23:59:59.000Z

    The use of radiation therapy is limited by the occurrence of the potentially fatal clinical syndromes of radiation pneumonitis and fibrosis. Radiation pneumonitis usually becomes clinically apparent from 2 to 6 months after completion of radiation therapy. It is characterized by fever, cough, dyspnea, and alveolar infiltrates on chest roentgenogram and may be difficult to differentiate from infection or recurrent malignancy. The pathogenesis is uncertain, but appears to involve both direct lung tissue toxicity and an inflammatory response. The syndrome may resolve spontaneously or may progress to respiratory failure. Corticosteroids may be effective therapy if started early in the course of the disease. The time course for the development of radiation fibrosis is later than that for radiation pneumonitis. It is usually present by 1 year following irradiation, but may not become clinically apparent until 2 years after radiation therapy. It is characterized by the insidious onset of dyspnea on exertion. It most often is mild, but can progress to chronic respiratory failure. There is no known successful treatment for this condition. 51 references.

  3. Radiation-induced gene responses

    SciTech Connect (OSTI)

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

    1996-12-31T23:59:59.000Z

    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.

  4. Dose Reduction Techniques

    SciTech Connect (OSTI)

    WAGGONER, L.O.

    2000-05-16T23:59:59.000Z

    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.

  5. SU-E-J-190: Characterization of Radiation Induced CT Number Changes in Tumor and Normal Lung During Radiation Therapy for Lung Cancer

    SciTech Connect (OSTI)

    Yang, C; Liu, F; Tai, A; Gore, E; Johnstone, C; Li, X [Medical College of Wisconsin Milwaukee WI (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To measure CT number (CTN) changes in tumor and normal lung as a function of radiation therapy (RT) dose during the course of RT delivery for lung cancer using daily IGRT CT images and single respiration phase CT images. Methods: 4D CT acquired during planning simulation and daily 3D CT acquired during daily IGRT for 10 lung cancer cases randomly selected in terms of age, caner type and stage, were analyzed using an in-house developed software tool. All patients were treated in 2 Gy fractions to primary tumors and involved nodal regions. Regions enclosed by a series of isodose surfaces in normal lung were delineated. The obtained contours along with target contours (GTVs) were populated to each singlephase planning CT and daily CT. CTN in term of Hounsfield Unit (HU) of each voxel in these delineated regions were collectively analyzed using histogram, mean, mode and linear correlation. Results: Respiration induced normal lung CTN change, as analyzed from single-phase planning CTs, ranged from 9 to 23 (2) HU for the patients studied. Normal lung CTN change was as large as 50 (12) HU over the entire treatment course, was dose and patient dependent and was measurable with dose changes as low as 1.5 Gy. For patients with obvious tumor volume regression, CTN within the GTV drops monotonically as much as 10 (1) HU during the early fractions with a total dose of 20 Gy delivered. The GTV and CTN reductions are significantly correlated with correlation coefficient >0.95. Conclusion: Significant RT dose induced CTN changes in lung tissue and tumor region can be observed during even the early phase of RT delivery, and may potentially be used for early prediction of radiation response. Single respiration phase CT images have dramatically reduced statistical noise in ROIs, making daily dose response evaluation possible.

  6. Dose Uncertainties in IMPT for Oropharyngeal Cancer in the Presence of Anatomical, Range, and Setup Errors

    SciTech Connect (OSTI)

    Kraan, Aafke C., E-mail: aafke.kraan@pi.infn.it [Erasmus MC Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Water, Steven van de; Teguh, David N.; Al-Mamgani, Abrahim [Erasmus MC Daniel den Hoed Cancer Center, Rotterdam (Netherlands); Madden, Tom; Kooy, Hanne M. [Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts (United States); Heijmen, Ben J.M.; Hoogeman, Mischa S. [Erasmus MC Daniel den Hoed Cancer Center, Rotterdam (Netherlands)

    2013-12-01T23:59:59.000Z

    Purpose: Setup, range, and anatomical uncertainties influence the dose delivered with intensity modulated proton therapy (IMPT), but clinical quantification of these errors for oropharyngeal cancer is lacking. We quantified these factors and investigated treatment fidelity, that is, robustness, as influenced by adaptive planning and by applying more beam directions. Methods and Materials: We used an in-house treatment planning system with multicriteria optimization of pencil beam energies, directions, and weights to create treatment plans for 3-, 5-, and 7-beam directions for 10 oropharyngeal cancer patients. The dose prescription was a simultaneously integrated boost scheme, prescribing 66 Gy to primary tumor and positive neck levels (clinical target volume-66 Gy; CTV-66 Gy) and 54 Gy to elective neck levels (CTV-54 Gy). Doses were recalculated in 3700 simulations of setup, range, and anatomical uncertainties. Repeat computed tomography (CT) scans were used to evaluate an adaptive planning strategy using nonrigid registration for dose accumulation. Results: For the recalculated 3-beam plans including all treatment uncertainty sources, only 69% (CTV-66 Gy) and 88% (CTV-54 Gy) of the simulations had a dose received by 98% of the target volume (D98%) >95% of the prescription dose. Doses to organs at risk (OARs) showed considerable spread around planned values. Causes for major deviations were mixed. Adaptive planning based on repeat imaging positively affected dose delivery accuracy: in the presence of the other errors, percentages of treatments with D98% >95% increased to 96% (CTV-66 Gy) and 100% (CTV-54 Gy). Plans with more beam directions were not more robust. Conclusions: For oropharyngeal cancer patients, treatment uncertainties can result in significant differences between planned and delivered IMPT doses. Given the mixed causes for major deviations, we advise repeat diagnostic CT scans during treatment, recalculation of the dose, and if required, adaptive planning to improve adequate IMPT dose delivery.

  7. Mechanisms of Low Dose Radio-Suppression of Genomic Instability

    SciTech Connect (OSTI)

    Engelward, Bevin P

    2009-09-16T23:59:59.000Z

    The major goal of this project is to contribute toward the elucidation of the impact of long term low dose radiation on genomic stability. We have created and characterized novel technologies for delivering long term low dose radiation to animals, and we have studied genomic stability by applying cutting edge molecular analysis technologies. Remarkably, we have found that a dose rate that is 300X higher than background radiation does not lead to any detectable genomic damage, nor is there any significant change in gene expression for genes pertinent to the DNA damage response. These results point to the critical importance of dose rate, rather than just total dose, when evaluating public health risks and when creating regulatory guidelines. In addition to these studies, we have also further developed a mouse model for quantifying cells that have undergone a large scale DNA sequence rearrangement via homologous recombination, and we have applied these mice in studies of both low dose radiation and space radiation. In addition to more traditional approaches for assessing genomic stability, we have also explored radiation and possible beneficial effects (adaptive response), long term effects (persistent effects) and effects on communication among cells (bystander effects), both in vitro and in vivo. In terms of the adaptive response, we have not observed any significant induction of an adaptive response following long term low dose radiation in vivo, delivered at 300X background. In terms of persistent and bystander effects, we have revealed evidence of a bystander effect in vivo and with researchers at and demonstrated for the first time the molecular mechanism by which cells remember radiation exposure. Understanding the underlying molecular mechanisms by which radiation can induce genomic instability is fundamental to our ability to assess the biological impact of low dose radiation. Finally, in a parallel set of studies we have explored the effects of heavy iron particle radiation on large scale sequence rearrangements and we have discovered tissue specific differences in sensitivity to homologous recombination. DOE support has given rise to critical new knowledge about the biological impact of low dose rate radiation and about the underlying mechanisms that govern genomic stability in response to radiation exposure. This work has spurred interest in radiation among MIT scientists, and has fostered ongoing research projects that will continue to contribute toward our understanding of the biological effects of low dose radiation exposure.

  8. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1991-01-01T23:59:59.000Z

    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.

  9. Radiotherapy Adapted to Spatial and Temporal Variability in Tumor Hypoxia

    SciTech Connect (OSTI)

    Sovik, Aste [Department of Medical Physics, Norwegian Radium Hospital, Oslo (Norway); Department of Physics, University of Oslo, Oslo (Norway); Malinen, Eirik [Department of Medical Physics, Norwegian Radium Hospital, Oslo (Norway) and Department of Physics, University of Oslo, Oslo (Norway)]. E-mail: emalinen@fys.uio.no; Skogmo, Hege K. [Department of Companion Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo (Norway); Bentzen, Soren M. [Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin (United States); Bruland, Oyvind S. [Department of Oncology, Norwegian Radium Hospital, Oslo (Norway); Department of Clincal Medicine, University of Oslo, Oslo (Norway); Olsen, Dag Rune [Department of Physics, University of Oslo, Oslo (Norway); Department of Radiation Biology, Norwegian Radium Hospital, Oslo (Norway)

    2007-08-01T23:59:59.000Z

    Purpose: To explore the feasibility and clinical potential of adapting radiotherapy to temporal and spatial variations in tumor oxygenation. Methods and Materials: Repeated dynamic contrast enhanced magnetic resonance (DCEMR) images were taken of a canine sarcoma during the course of fractionated radiation therapy. The tumor contrast enhancement was assumed to represent the oxygen distribution. The IMRT plans were retrospectively adapted to the DCEMR images by employing tumor dose redistribution. Optimized nonuniform tumor dose distributions were calculated and compared with a uniform dose distribution delivering the same integral dose to the tumor. Clinical outcome was estimated from tumor control probability (TCP) and normal tissue complication probability (NTCP) modeling. Results: The biologically adapted treatment was found to give a substantial increase in TCP compared with conventional radiotherapy, even when only pretreatment images were used as basis for the treatment planning. The TCP was further increased by repeated replanning during the course of treatment, and replanning twice a week was found to give near optimal TCP. Random errors in patient positioning were found to give a small decrease in TCP, whereas systematic errors were found to reduce TCP substantially. NTCP for the adapted treatment was similar to or lower than for the conventional treatment, both for parallel and serial normal tissue structures. Conclusion: Biologically adapted radiotherapy is estimated to improve treatment outcome of tumors having spatial and temporal variations in radiosensitivity.

  10. Flavin-Induced Oligomerization in Escherichia coli Adaptive Response Protein AidB

    E-Print Network [OSTI]

    Drennan, Catherine L.

    The process known as adaptive response allows Escherichia coli to respond to small doses of DNA-methylating agents by upregulating the expression of four proteins. While the role of three of these proteins in mitigating ...

  11. Comparison of Different Forms of Creatine on Creatine Availability, Retention, and Training Adaptations

    E-Print Network [OSTI]

    Jagim, Andrew Ryan

    2013-03-25T23:59:59.000Z

    The purpose of this study was to determine if a buffered creatine monohydrate (KA) that has been purported to promote greater creatine retention and training adaptations with fewer side effects at lower doses is more ...

  12. Standardized radiological dose evaluations

    SciTech Connect (OSTI)

    Peterson, V.L.; Stahlnecker, E.

    1996-05-01T23:59:59.000Z

    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.

  13. Radiation-induced back-channel leakage in SiGe CMOS on silicon-on-sapphire (S0S) technology

    SciTech Connect (OSTI)

    Mathew, S.J.; Niu, G.; Clark, S.D.; Cressler, J.D.; Palmer, M.J.; Dubbelday, W.B.

    1999-12-01T23:59:59.000Z

    The authors report the first results of a high-energy gamma irradiation experiment on SiGe CMOS on silicon-on-sapphire (SOS) technology. In contrast to bulk Si CMOS, with increasing total dose the pFET's develop a significant off-state leakage, while the nFET's show a reduction in the leakage, which the authors attribute to negative charge trapping at the back Si-sapphire interface. Both the Si and SiGe pFET's showed the enhancement in leakage, suggesting that the leakage mechanism was not related to the SiGe channel. When the devices were cooled to liquid-nitrogen temperature, the leakage disappears completely, suggesting that the trapping mechanism is strongly temperature dependent.

  14. ORISE: Dose modeling and assessments

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (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...

  15. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1992-06-01T23:59:59.000Z

    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.

  16. New Insights into Fully-Depleted SOI Transistor Response During Total-Dose Irradiation

    SciTech Connect (OSTI)

    BURNS,J.A.; DODD,PAUL E.; KEAST,C.L.; SCHWANK,JAMES R.; SHANEYFELT,MARTY R.; WYATT,P.W.

    1999-09-14T23:59:59.000Z

    Previous work showed the possible existence of a total-dose latch effect in fully-depleted SOI transistors that could severely limit the radiation hardness of SOI devices. Other work showed that worst-case bias configuration during irradiation was the transmission gate bias configuration. In this work we further explore the effects of total-dose ionizing irradiation on fully-depleted SOI transistors. Closed-geometry and standard transistors fabricated in two fully-depleted processes were irradiated with 10-keV x rays. Our results show no evidence for a total-dose latch effect as proposed by others. Instead, in absence of parasitic trench sidewall leakage, our data suggests that the increase in radiation-induced leakage current is caused by positive charge trapping in the buried oxide inverting the back-channel interface. At moderate levels of trapped charge, the back-channel interface is slightly inverted causing a small leakage current to flow. This leakage current is amplified to considerably higher levels by impact ionization. Because the back-channel interface is in weak inversion, the top-gate bias can modulate the back-channel interface and turn the leakage current off at large, negative voltage levels. At high levels of trapped charge, the back-channel interface is fully inverted and the gate bias has little effect on leakage current. However, it is likely that this current also is amplified by impact ionization. For these transistors, the worst-case bias configuration was determined to be the ''ON'' bias configuration. These results have important implication on hardness assurance.

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

    SciTech Connect (OSTI)

    Eric Y. Chuang

    2006-08-31T23:59:59.000Z

    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.

  18. Online Adaptive Replanning Method for Prostate Radiotherapy

    SciTech Connect (OSTI)

    Ahunbay, Ergun E., E-mail: eahunbay@mcw.ed [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States); Peng Cheng; Holmes, Shannon; Godley, Andrew; Lawton, Colleen; Li, X. Allen [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI (United States)

    2010-08-01T23:59:59.000Z

    Purpose: To report the application of an adaptive replanning technique for prostate cancer radiotherapy (RT), consisting of two steps: (1) segment aperture morphing (SAM), and (2) segment weight optimization (SWO), to account for interfraction variations. Methods and Materials: The new 'SAM+SWO' scheme was retroactively applied to the daily CT images acquired for 10 prostate cancer patients on a linear accelerator and CT-on-Rails combination during the course of RT. Doses generated by the SAM+SWO scheme based on the daily CT images were compared with doses generated after patient repositioning using the current planning target volume (PTV) margin (5 mm, 3 mm toward rectum) and a reduced margin (2 mm), along with full reoptimization scans based on the daily CT images to evaluate dosimetry benefits. Results: For all cases studied, the online replanning method provided significantly better target coverage when compared with repositioning with reduced PTV (13% increase in minimum prostate dose) and improved organ sparing when compared with repositioning with regular PTV (13% decrease in the generalized equivalent uniform dose of rectum). The time required to complete the online replanning process was 6 {+-} 2 minutes. Conclusion: The proposed online replanning method can be used to account for interfraction variations for prostate RT with a practically acceptable time frame (5-10 min) and with significant dosimetric benefits. On the basis of this study, the developed online replanning scheme is being implemented in the clinic for prostate RT.

  19. Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens

    SciTech Connect (OSTI)

    Goldstein, Lee [Boston University] [Boston University

    2014-07-02T23:59:59.000Z

    This is the Final Progress Report for DOE-funded research project DE-PS02-08ER08-01 titled Non-Invasive Early Detection and Molecular Analysis of Low X-ray Dose Effects in the Lens. The project focuses on the effects of low-linear energy transfer (LET) radiation on the ocular lens. The lens is an exquisitely radiosensitive tissue with a highly-ordered molecular structure that is amenable to non-invasive optical study from the periphery. These merits point to the lens as an ideal target for laser-based molecular biodosimetry (MBD). Following exposure to different types of ionizing radiations, the lens demonstrates molecular changes (e.g., oxidation, racemization, crosslinkage, truncation, aggregation, etc.) that impact the structure and function of the long-lived proteins in the cytosol of lens fiber cells. The vast majority of proteins in the lens comprise the highly-ordered crystallins. These highly conserved lens proteins are amongst the most concentrated and stable in the body. Once synthesized, the crystallins are retained in the fiber cell cytoplasm for life. Taken together, these properties point to the lens as an ideal system for quantitative in vivo MBD assessment using quasi-elastic light scattering (QLS) analysis. In this project, we deploy a purpose-designed non-invasive infrared laser QLS instrument as a quantitative tool for longitudinal assessment of pre-cataractous molecular changes in the lenses of living mice exposed to low-dose low-LET radiation compared to non-irradiated sham controls. We hypothesize that radiation exposure will induce dose-dependent changes in the molecular structure of matrix proteins in the lens. Mechanistic assays to ascertain radiation-induced molecular changes in the lens focus on protein aggregation and gene/protein expression patterns. We anticipate that this study will contribute to our understanding of early molecular changes associated with radiation-induced tissue pathology. This study also affords potential for translational development of molecular biodosimetry instrumentation to assess human exposure to mixed radiation fields.

  20. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

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

    1992-07-01T23:59:59.000Z

    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.

  1. Biologically Effective Dose-Response Relationship for Breast Cancer Treated by Conservative Surgery and Postoperative Radiotherapy

    SciTech Connect (OSTI)

    Plataniotis, George A. [Department of Oncology, Aberdeen Royal Infirmary, Aberdeen (United Kingdom)], E-mail: george.plataniotis@nhs.net; Dale, Roger G. [Imperial College Healthcare NHS Trust, London (United Kingdom)

    2009-10-01T23:59:59.000Z

    Purpose: To find a biologically effective dose (BED) response for adjuvant breast radiotherapy (RT) for initial-stage breast cancer. Methods and Materials: Results of randomized trials of RT vs. non-RT were reviewed and the tumor control probability (TCP) after RT was calculated for each of them. Using the linear-quadratic formula and Poisson statistics of cell-kill, the average initial number of clonogens per tumor before RT and the average tumor cell radiosensitivity (alpha-value) were calculated. An {alpha}/{beta} ratio of 4 Gy was assumed for these calculations. Results: A linear regression equation linking BED to TCP was derived: -ln[-ln(TCP)] = -ln(No) + {alpha}{sup *} BED = -4.08 + 0.07 * BED, suggesting a rather low radiosensitivity of breast cancer cells (alpha = 0.07 Gy{sup -1}), which probably reflects population heterogeneity. From the linear relationship a sigmoid BED-response curve was constructed. Conclusion: For BED values higher than about 90 Gy{sub 4} the radiation-induced TCP is essentially maximizing at 90-100%. The relationship presented here could be an approximate guide in the design and reporting of clinical trials of adjuvant breast RT.

  2. 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 (OSTI)

    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

    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.

  3. Technical basis for dose reconstruction

    SciTech Connect (OSTI)

    Anspaugh, L.R.

    1996-01-31T23:59:59.000Z

    The purpose of this paper is to consider two general topics: technical considerations of why dose-reconstruction studies should or should not be performed and methods of dose reconstruction. The first topic is of general and growing interest as the number of dose-reconstruction studies increases, and one asks the question whether it is necessary to perform a dose reconstruction for virtually every site at which, for example, the Department of Energy (DOE) has operated a nuclear-related facility. And there is the broader question of how one might logically draw the line at performing or not performing dose-reconstruction (radiological and chemical) studies for virtually every industrial complex in the entire country. The second question is also of general interest. There is no single correct way to perform a dose-reconstruction study, and it is important not to follow blindly a single method to the point that cheaper, faster, more accurate, and more transparent methods might not be developed and applied.

  4. Weldon Spring historical dose estimate

    SciTech Connect (OSTI)

    Meshkov, N.; Benioff, P.; Wang, J.; Yuan, Y.

    1986-07-01T23:59:59.000Z

    This study was conducted to determine the estimated radiation doses that individuals in five nearby population groups and the general population in the surrounding area may have received as a consequence of activities at a uranium processing plant in Weldon Spring, Missouri. The study is retrospective and encompasses plant operations (1957-1966), cleanup (1967-1969), and maintenance (1969-1982). The dose estimates for members of the nearby population groups are as follows. Of the three periods considered, the largest doses to the general population in the surrounding area would have occurred during the plant operations period (1957-1966). Dose estimates for the cleanup (1967-1969) and maintenance (1969-1982) periods are negligible in comparison. Based on the monitoring data, if there was a person residing continually in a dwelling 1.2 km (0.75 mi) north of the plant, this person is estimated to have received an average of about 96 mrem/yr (ranging from 50 to 160 mrem/yr) above background during plant operations, whereas the dose to a nearby resident during later years is estimated to have been about 0.4 mrem/yr during cleanup and about 0.2 mrem/yr during the maintenance period. These values may be compared with the background dose in Missouri of 120 mrem/yr.

  5. a 50% reduction in Prlr gene dose, provides strong evidence for PRL being the mediator

    E-Print Network [OSTI]

    Kenig, Fabien

    a 50% reduction in Prlr gene dose, provides strong evidence for PRL being the mediator of pregnancy adaptation initiated early in pregnancy and mediated by PRL. Pregnancy is associated with several other transient alterations in mater- nal physiological functions, many of which can be affected by PRL and

  6. Defect Sink Characteristics of Specific Grain Boundary Types in 304 Stainless Steels Under High Dose Neutron Environments

    SciTech Connect (OSTI)

    Field, Kevin G [ORNL; Yang, Ying [ORNL; Busby, Jeremy T [ORNL

    2015-01-01T23:59:59.000Z

    Radiation induced segregation (RIS) is a well-studied phenomena which occurs in many structurally relevant nuclear materials including austenitic stainless steels. RIS occurs due to solute atoms preferentially coupling to mobile point defect fluxes that migrate and interact with defect sinks. Here, a 304 stainless steel was neutron irradiated up to 47.1 dpa at 320 C. Investigations into the RIS response at specific grain boundary types were utilized to determine the sink characteristics of different boundary types as a function of irradiation dose. A rate theory model built on the foundation of the modified inverse Kirkendall (MIK) model is proposed and benchmarked to the experimental results. This model, termed the GiMIK model, includes alterations in the boundary conditions based on grain boundary structure and includes expressions for interstitial binding. This investigation, through experiment and modeling, found specific grain boundary structures exhibit unique defect sink characteristics depending on their local structure. Such interactions were found to be consistent across all doses investigated and had larger global implications including precipitation of Ni-Si clusters near different grain boundary types.

  7. Biological doses with template distribution patterns

    SciTech Connect (OSTI)

    Harrop, R. (Simon Fraer Univ., Burnaby, British Columbia); Haymond, H.R.; Nisar, A.; Syed, A.N.M.; Feder, B.H.; Neblett, D.L.

    1981-02-01T23:59:59.000Z

    Consideration of radiation dose rate effects emphasizes advantages of the template method for lateral distribution of multiple sources in treatment of laterally infiltrating gynecologic cancer, when compared to a conventional technique with colpostats. Biological doses in time dose fractionation (TDF), ret and reu units are calculated for the two treatment methods. With the template method the lateral dose (point B) is raised without significantly increasing the doses to the rectum and bladder, that is, relatively, the calculated biological doses at point A and B are more nearly equivalent and the doses to the rectum and bladder are significantly lower than the dose to point B.

  8. Adaptive Street Lighting Controls

    Broader source: Energy.gov [DOE]

    This two-partDOE 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...

  9. Climate Change Adaptation Planning

    Office of Energy Efficiency and Renewable Energy (EERE)

    This course provides an introduction to planning for climate change impacts, with examples of tribes that have been going through the adaptation planning process. The course is intended for tribal...

  10. A Phase I Clinical and Pharmacology Study Using Amifostine as a Radioprotector in Dose-escalated Whole Liver Radiation Therapy

    SciTech Connect (OSTI)

    Feng, Mary, E-mail: maryfeng@umich.edu [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Smith, David E. [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States); Normolle, Daniel P. [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States)] [Department of Biostatistics, University of Pittsburgh, Pittsburgh, Pennsylvania (United States); Knol, James A. [Department of Surgery, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Surgery, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Pan, Charlie C.; Ben-Josef, Edgar [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Lu Zheng; Feng, Meihua R.; Chen Jun [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan (United States); Ensminger, William [Department of Internal Medicine, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Internal Medicine, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States); Lawrence, Theodore S. [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, School of Medicine, University of Michigan, Ann Arbor, Michigan (United States)

    2012-08-01T23:59:59.000Z

    Purpose: Diffuse intrahepatic tumors are difficult to control. Whole-liver radiotherapy has been limited by toxicity, most notably radiation-induced liver disease. Amifostine is a prodrug free-radical scavenger that selectively protects normal tissues and, in a preclinical model of intrahepatic cancer, systemic amifostine reduced normal liver radiation damage without compromising tumor effect. We hypothesized that amifostine would permit escalation of whole-liver radiation dose to potentially control microscopic disease. We also aimed to characterize the pharmacokinetics of amifostine and its active metabolite WR-1065 to optimize timing of radiotherapy. Methods and Materials: We conducted a radiation dose-escalation trial for patients with diffuse, intrahepatic cancer treated with whole-liver radiation and intravenous amifostine. Radiation dose was assigned using the time-to-event continual reassessment method. A companion pharmacokinetic study was performed. Results: Twenty-three patients were treated, with a maximum dose of 40 Gy. Using a logistical regression model, compared with our previously treated patients, amifostine increased liver tolerance by 3.3 {+-} 1.1 Gy (p = 0.007) (approximately 10%) with similar response rates. Peak concentrations of WR-1065 were 25 {mu}M with an elimination half-life of 1.5 h; these levels are consistent with radioprotective effects of amifostine in patients. Conclusion: These findings demonstrate for the first time that amifostine is a normal liver radioprotector. They further suggest that it may be useful to combine amifostine with fractionated or stereotactic body radiation therapy for patients with focal intrahepatic cancer.

  11. Discriminative Adaptive Training and Bayesian Inference for

    E-Print Network [OSTI]

    de Gispert, Adrià

    adaptation is a standard part of many speech recognition systems. This process requires some adaptation data

  12. Radiation dose delivered to the proximal penis as a predictor of the risk of erectile dysfunction after three-dimensional conformal radiotherapy for localized prostate cancer

    SciTech Connect (OSTI)

    Wernicke, A. Gabriella [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Valicenti, Richard [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States)]. E-mail: richard.valicenti@mail.tju.edu; DiEva, Kelly [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Houser, Christopher [Department of Radiation Oncology, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania (United States); Pequignot, Ed [Department of Medicine, Jefferson Medical College and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA (United States)

    2004-12-01T23:59:59.000Z

    Purpose/objective: In this study, we evaluated in a serial manner whether radiation dose to the bulb of the penis is predictive of erectile dysfunction, ejaculatory difficulty (EJ), and overall satisfaction with sex life (quality of life) by using serial validated self-administered questionnaires. Methods and materials: Twenty-nine potent men with AJCC Stage II prostate cancer treated with three-dimensional conformal radiation therapy alone to a median dose 72.0 Gy (range: 66.6-79.2 Gy) were evaluated by determining the doses received by the penile bulb. The penile bulb was delineated volumetrically, and the dose-volume histogram was obtained on each patient. Results: The median follow-up time was 35 months (range, 16-43 months). We found that for D{sub 30}, D{sub 45}, D{sub 60}, and D{sub 75} (doses to a percent volume of PB: 30%, 45%, 60%, and 75%), higher than the corresponding median dose (defined as high-dose group) correlated with an increased risk of impotence (erectile dysfunction firmness score = 0) (odds ratio [OR] = 7.5, p = 0.02; OR = 7.5, p = 0.02; OR = 8.6, p = 0.008; and OR = 6.9, p = 0.015, respectively). Similarly, for EJD D{sub 30}, D{sub 45}, D{sub 60}, and D{sub 75}, doses higher than the corresponding median ones correlated with worsening ejaculatory function score (EJ = 0 or 1) (OR = 8, p = 0.013; OR = 8, p 0.013; OR = 9.2, p = 0.015; and OR = 8, p = 0.026, respectively). For quality of life, low ({<=}median dose) dose groups of patients improve over time, whereas high-dose groups of patients worsen. Conclusions: This study supports the existence of a penile bulb dose-volume relationship underlying the development of radiation-induced erectile dysfunction. Our data may guide the use of inverse treatment planning to maximize the probability of maintaining sexual potency after radiation therapy.

  13. AGING FACILITY WORKER DOSE ASSESSMENT

    SciTech Connect (OSTI)

    R.L. Thacker

    2005-03-24T23:59:59.000Z

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Aging Facility performing operations to transfer aging casks to the aging pads for thermal and logistical management, stage empty aging casks, and retrieve aging casks from the aging pads for further processing in other site facilities. Doses received by workers due to aging cask surveillance and maintenance operations are also included. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation. There are no Category 1 event sequences associated with the Aging Facility (BSC 2004 [DIRS 167268], Section 7.2.1). The results of this calculation will be used to support the design of the Aging Facility and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in Environmental and Nuclear Engineering.

  14. Organizational Adaptation Kathleen M. Carley

    E-Print Network [OSTI]

    Sadeh, Norman M.

    Organizational Adaptation Kathleen M. Carley Dept. of Social and Decision Sciences Carnegie Mellon: Kathleen M. Carley, 1998, "Organizational Adaptation." Annals of Operations Research. 75: 25-47. #12;Organizational Adaptation A computational model of organizational adaptation in which change occurs at both

  15. Direct aperture optimization for online adaptive radiation therapy

    SciTech Connect (OSTI)

    Mestrovic, Ante; Milette, Marie-Pierre; Nichol, Alan; Clark, Brenda G.; Otto, Karl [Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada and Medical Physics, BC Cancer Agency-Vancouver Centre, Vancouver, British Columbia (Canada); Physics and Astronomy, University of British Columbia, Vancouver, British Columbia (Canada) and Medical Physics, BC Cancer Agency-Centre for the Southern Interior, Kelowna, British Columbia (Canada); Department of Radiation Oncology, BC Cancer Agency-Vancouver Centre, Vancouver, British Columbia (Canada); Medical Physics, Ottawa Hospital Regional Cancer Centre, Ottawa, Ontario (Canada); Medical Physics, BC Cancer Agency-Vancouver Centre, Vancouver, British Columbia (Canada)

    2007-05-15T23:59:59.000Z

    This paper is the first investigation of using direct aperture optimization (DAO) for online adaptive radiation therapy (ART). A geometrical model representing the anatomy of a typical prostate case was created. To simulate interfractional deformations, four different anatomical deformations were created by systematically deforming the original anatomy by various amounts (0.25, 0.50, 0.75, and 1.00 cm). We describe a series of techniques where the original treatment plan was adapted in order to correct for the deterioration of dose distribution quality caused by the anatomical deformations. We found that the average time needed to adapt the original plan to arrive at a clinically acceptable plan is roughly half of the time needed for a complete plan regeneration, for all four anatomical deformations. Furthermore, through modification of the DAO algorithm the optimization search space was reduced and the plan adaptation was significantly accelerated. For the first anatomical deformation (0.25 cm), the plan adaptation was six times more efficient than the complete plan regeneration. For the 0.50 and 0.75 cm deformations, the optimization efficiency was increased by a factor of roughly 3 compared to the complete plan regeneration. However, for the anatomical deformation of 1.00 cm, the reduction of the optimization search space during plan adaptation did not result in any efficiency improvement over the original (nonmodified) plan adaptation. The anatomical deformation of 1.00 cm demonstrates the limit of this approach. We propose an innovative approach to online ART in which the plan adaptation and radiation delivery are merged together and performed concurrently--adaptive radiation delivery (ARD). A fundamental advantage of ARD is the fact that radiation delivery can start almost immediately after image acquisition and evaluation. Most of the original plan adaptation is done during the radiation delivery, so the time spent adapting the original plan does not increase the overall time the patient has to spend on the treatment couch. As a consequence, the effective time allotted for plan adaptation is drastically reduced. For the 0.25, 0.5, and 0.75 cm anatomical deformations, the treatment time was increased by only 2, 4, and 6 s, respectively, as compared to no plan adaptation. For the anatomical deformation of 1.0 cm the time increase was substantially larger. The anatomical deformation of 1.0 cm represents an extreme case, which is rarely observed for the prostate, and again demonstrates the limit of this approach. ARD shows great potential for an online adaptive method with minimal extension of treatment time.

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

    SciTech Connect (OSTI)

    Simon Bouffler; Christophe Badie; Natalie Brown; Rosemary Finnon

    2010-07-28T23:59:59.000Z

    This report provides a full summary of the results obtained under grant DE-FG02-05ER63947, Radiation Leukaemogenesis at low doses. The studies employed an experimental model of radiation leukaemogenesis with the main aim of identifying key events that convert normal cells into leukaemic cells follwoing exposure to radiation. Important aspect of the work was to understand dose-response relationships and time course relationships for leakaemogenis events. The studies performed provided evidence for direct radiation-induced losses of the Sfpi1/PU.1 gene being critical for induction of the disease. No threshold below 0.1 Gy in the induction of the gene losses was observed. The critical cell type in which the myeloid lekaemias arise has been identified and point mutations in the Sfpi1/PU.1 gene are common in leukaemias. The consequences of the genetic losses and mutation have been examined and these provide evidence of a disruption of differentiation in leukaemic cells. Additional pathways to leukaemogenesis have been identified also. Overall the study provides quantitiative data suitable for testing approaches to modelling of leukaemia rosk at low doses.

  17. Adaptive Medical Information Delivery Combining User, Task and Situation Models

    E-Print Network [OSTI]

    ., in their model for adaptive hypermedia AHAM [2], distinguish contentadaptation from link adaptation

  18. Static jaw collimation settings to minimize radiation dose to normal brain tissue during stereotactic radiosurgery

    SciTech Connect (OSTI)

    Han, Eun Young, E-mail: eyhan@uams.edu [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Zhang Xin; Yan Yulong; Sharma, Sunil; Penagaricano, Jose [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States); Moros, Eduardo [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States); Corry, Peter [Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, AR (United States)

    2012-01-01T23:59:59.000Z

    At University of Arkansas for Medical Sciences (UAMS) intracranial stereotactic radiosurgery (SRS) is performed by using a linear accelerator with an add-on micromultileaf collimator (mMLC). In our clinical setting, static jaws are automatically adapted to the furthest edge of the mMLC-defined segments with 2-mm (X jaw) and 5-mm (Y jaw) margin and the same jaw values are applied for all beam angles in the treatment planning system. This additional field gap between the static jaws and the mMLC allows additional radiation dose to normal brain tissue. Because a radiosurgery procedure consists of a single high dose to the planning target volume (PTV), reduction of unnecessary dose to normal brain tissue near the PTV is important, particularly for pediatric patients whose brains are still developing or when a critical organ, such as the optic chiasm, is near the PTV. The purpose of this study was to minimize dose to normal brain tissue by allowing minimal static jaw margin around the mMLC-defined fields and different static jaw values for each beam angle or arc. Dose output factors were measured with various static jaw margins and the results were compared with calculated doses in the treatment planning system. Ten patient plans were randomly selected and recalculated with zero static jaw margins without changing other parameters. Changes of PTV coverage, mean dose to predefined normal brain tissue volume adjacent to PTV, and monitor units were compared. It was found that the dose output percentage difference varied from 4.9-1.3% for the maximum static jaw opening vs. static jaw with zero margins. The mean dose to normal brain tissue at risk adjacent to the PTV was reduced by an average of 1.9%, with negligible PTV coverage loss. This dose reduction strategy may be meaningful in terms of late effects of radiation, particularly in pediatric patients. This study generated clinical knowledge and tools to consistently minimize dose to normal brain tissue.

  19. Mitigation of radiation induced surface contamination

    DOE Patents [OSTI]

    Klebanoff, Leonard E. (Dublin, CA); Stulen, Richard H. (Livermore, CA)

    2003-01-01T23:59:59.000Z

    A process for mitigating or eliminating contamination and/or degradation of surfaces having common, adventitious atmospheric contaminants adsorbed thereon and exposed to radiation. A gas or a mixture of gases is introduced into the environment of a surface(s) to be protected. The choice of the gaseous species to be introduced (typically a hydrocarbon gas, water vapor, or oxygen or mixtures thereof) is dependent upon the contaminant as well as the ability of the gaseous species to bind to the surface to be protected. When the surface and associated bound species are exposed to radiation reactive species are formed that react with surface contaminants such as carbon or oxide films to form volatile products (e.g., CO, CO.sub.2) which desorb from the surface.

  20. Radiation Induced Nanocrystal Formation in Metallic Glasses

    E-Print Network [OSTI]

    Carter, Jesse

    2010-01-14T23:59:59.000Z

    simple system consisting of only two elements, several intermetallic compounds can exist, each with their own crystal structure (face-centered cubic, body-centered, etc), and the system gets much more complicated when the number of constituents... of Alloys and Compounds, Vol 431, Q.S. Zhang, W. Zhang, G.Q. Xie, K.S. Nakayama, H. Kimura and A. Inoue, Formation of bulk metallic glass in situ composites in Cu50Zr45Ti5 alloy, Pages 236-240, Copyright 2007, with permission from Elsevier. 16 Fig. 9...

  1. Radiation Induced Nanocrystal Formation in Metallic Glasses

    E-Print Network [OSTI]

    Carter, Jesse

    2010-01-14T23:59:59.000Z

    The irradiation of metallic glasses to induce nanocrystallization was studied in two metallic glass compositions, Cu50Zr45Ti5 and Zr55Cu30Al10Ni5. Atomic mobility was described using a model based on localized excess free volume due to displace...

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

    SciTech Connect (OSTI)

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

    1993-04-01T23:59:59.000Z

    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.

  3. Adaptation and adaptability : expectant design for resilience in coastal urbanity

    E-Print Network [OSTI]

    Ruskeep, Laura A. Delaney (Laura Ashley Delaney)

    2011-01-01T23:59:59.000Z

    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 ...

  4. Adaptive sequential controller

    DOE Patents [OSTI]

    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

    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.

  5. CONTRIBUTED Adaptive Stochastic Control

    E-Print Network [OSTI]

    Powell, Warren B.

    sources, many forms of energy storage, and microgrid management (see Fig. 1). Computationally, controlling of distributed generation and storage within the Smart Grid. KEYWORDS | Adaptive stochastic control (ASC.g., factory assembly lines, petrochemical plants, and nuclear power plants). Below we describe

  6. ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS

    E-Print Network [OSTI]

    ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS MOODY T. CHU Abstract. The wavefront aberrations induced by atmospheric turbulence can severely degrade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions

  7. ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS

    E-Print Network [OSTI]

    ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS MOODY T. CHU \\Lambda Abstract. The wavefront aberrations induced by atmospheric turbulence can severely degrade the performance of an optical imaging system. Adaptive optics refers to the process of removing unwanted wave front distortions

  8. RADIATION SENSITIVITY & PROCESSING OF DNA DAMAGE FOLLOWING LOW DOSES OF GAMMA-RAY ALPHA PARTICLES & HZE IRRADIATION OF NORMAL DSB REPAIR DEFICIENT CELLS

    SciTech Connect (OSTI)

    O'Neil, Peter

    2009-05-15T23:59:59.000Z

    Non-homologous end joining (NHEJ) predominates in the repair of DNA double strand breaks (DSB) over homologous recombination (HR). NHEJ occurs throughout the cell cycle whereas HR occurs in late S/G2 due to the requirement of a sister chromatid (Rothkamm et al, Mol Cell Biol 23 5706-15 [2003]). To date evidence obtained with DSB repair deficient cells using pulsed-field gel electrophoresis has revealed the major pathway throughout all phases of the cell cycle for processing high dose induced DSBs is NHEJ (Wang et al, Oncogene 20 2212-24 (2001); Pluth et al, Cancer Res. 61 2649-55 [2001]). These findings however were obtained at high doses when on average >> 20-30 DSBs are formed per cell. The contribution of the repair pathways (NHEJ and HR) induced in response to DNA damage during the various phases of the cell cycle may depend upon the dose (the level of initial DSBs) especially since low levels of DSBs are induced at low dose. To date, low dose studies using NHEJ and HR deficient mutants have not been carried out to address this important question with radiations of different quality. The work presented here leads us to suggest that HR plays a relatively minor role in the repair of radiation-induced prompt DSBs. SSBs lead to the induction of DSBs which are associated specifically with S-phase cells consistent with the idea that they are formed at stalled replication forks in which HR plays a major role in repair. That DNA-PKcs is in some way involved in the repair of the precursors to replication-induced DSB remains an open question. Persistent non-DSB oxidative damage also leads to an increase in RAD51 positive DSBs. Both simple and complex non-DSB DNA damage may therefore contribute to indirect DSBs induced by ionising radiation at replication forks.

  9. Tolerance doses for treatment planning

    SciTech Connect (OSTI)

    Lyman, J.T.

    1985-10-01T23:59:59.000Z

    Data for the tolerance of normal tissues or organs to (low-LET) radiation has been compiled from a number of sources which are referenced at the end of this document. This tolerance dose data are ostensibly for uniform irradiation of all or part of an organ, and are for either 5% (TD/sub 5/) or 50% (TD/sub 50/) complication probability. The ''size'' of the irradiated organ is variously stated in terms of the absolute volume or the fraction of the organ volume irradiated, or the area or the length of the treatment field. The accuracy of these data is questionable. Much of the data represents doses that one or several experienced therapists have estimated could be safely given rather than quantitative analyses of clinical observations. Because these data have been obtained from multiple sources with possible different criteria for the definition of a complication, there are sometimes different values for what is apparently the same endpoint. The data from some sources shows a tendancy to be quantized in 5 Gy increments. This reflects the size of possible round off errors. It is believed that all these data have been accumulated without the benefit of 3-D dose distributions and therefore the estimates of the size of the volume and/or the uniformity of the irradiation may be less accurate than is now possible. 19 refs., 4 figs.

  10. Adaptive Survey Design Andrew Sage

    E-Print Network [OSTI]

    Carriquiry, Alicia

    . Andrew Sage Iowa State University CSSM March 14, 2014 2 / 35 #12;Adaptive and Responsive Designs collection, although they may be revised during data collection. A responsive design is an adaptive design

  11. Climate Change, Adaptation, and Development

    E-Print Network [OSTI]

    Cole, Daniel H.

    2008-01-01T23:59:59.000Z

    Climate Change, Adaptation, and Development Daniel H. Cole*THE COSTS OF CLIMATE CHANGE . ADAPTATIONCONVENTION ON CLIMATE CHANGE . IV. A.

  12. Transforming Growth Factor ?-1 (TGF-?1) Is a Serum Biomarker of Radiation Induced Fibrosis in Patients Treated With Intracavitary Accelerated Partial Breast Irradiation: Preliminary Results of a Prospective Study

    SciTech Connect (OSTI)

    Boothe, Dustin L. [Weill Cornell Medical College of Cornell University, New York, New York (United States); Coplowitz, Shana [Department of Radiation Oncology, Stich Radiation Center, Weill Cornell Medical College of Cornell University, New York, New York (United States); Greenwood, Eleni [Weill Cornell Medical College of Cornell University, New York, New York (United States); Barney, Christian L. [Department of Radiation Oncology, Ohio State University, Columbus, Ohio (United States); Christos, Paul J. [Division of Biostatistics and Epidemiology, Department of Public Health, Weill Cornell Medical College of Cornell University, New York, New York (United States); Parashar, Bhupesh; Nori, Dattatreyudu; Chao, K. S. Clifford [Department of Radiation Oncology, Stich Radiation Center, Weill Cornell Medical College of Cornell University, New York, New York (United States); Wernicke, A. Gabriella, E-mail: gaw9008@med.cornell.edu [Department of Radiation Oncology, Stich Radiation Center, Weill Cornell Medical College of Cornell University, New York, New York (United States)

    2013-12-01T23:59:59.000Z

    Purpose: To examine a relationship between serum transforming growth factor ? -1 (TGF-?1) values and radiation-induced fibrosis (RIF). Methods and Materials: We conducted a prospective analysis of the development of RIF in 39 women with American Joint Committee on Cancer stage 0-I breast cancer treated with lumpectomy and accelerated partial breast irradiation via intracavitary brachytherapy (IBAPBI). An enzyme-linked immunoassay (Quantikine, R and D, Minneapolis, MN) was used to measure serum TGF-?1 before surgery, before IBAPBI, and during IBAPBI. Blood samples for TGF-?1 were also collected from 15 healthy, nontreated women (controls). The previously validated tissue compliance meter (TCM) was used to objectively assess RIF. Results: The median time to follow-up for 39 patients was 44 months (range, 5-59 months). RIF was graded by the TCM scale as 0, 1, 2, and 3 in 5 of 20 patients (25%), 6 of 20 patients (30%), 5 of 20 patients (25%), and 4 of 20 patients (20%), respectively. The mean serum TGF-?1 values were significantly higher in patients before surgery than in disease-free controls, as follows: all cancer patients (30,201 5889 pg/mL, P=.02); patients with any type of RIF (32,273 5016 pg/mL, P<.0001); and women with moderate to severe RIF (34,462 4713 pg/mL, P<0.0001). Patients with moderate to severe RIF had significantly elevated TGF-?1 levels when compared with those with none to mild RIF before surgery (P=.0014) during IBAPBI (P?0001), and the elevation persisted at 6 months (P?.001), 12 months (P?.001), 18 months (P?.001), and 24 months (P=.12). A receiver operating characteristic (ROC) curve of TGF-?1 values predicting moderate to severe RIF was generated with an area under the curve (AUC){sub ROC} of 0.867 (95% confidence interval 0.700-1.000). The TGF-?1 threshold cutoff was determined to be 31,000 pg/mL, with associated sensitivity and specificity of 77.8% and 90.0%, respectively. Conclusions: TGF-?1 levels correlate with the development of moderate to severe RIF. The pre-IBAPBI mean TGF-?1 levels can serve as an early biomarker for the development of moderate to severe RIF after IBAPBI.

  13. ON ADAPTIVE SAMPLING Philippe Flajolet

    E-Print Network [OSTI]

    Flajolet, Philippe

    . We analyze the storage/accuracy trade--off of an adaptive sampling algorithm due to Wegman that makes. Wegman [11] has proposed an interesting alternative solution to that problem based on Adaptive Sampling 4. 2 Wegman's Adaptive Sampling Method The problem discussed here is the following. We are given

  14. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1992-10-01T23:59:59.000Z

    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.

  15. Hanford Environmental Dose Reconstruction Project Monthly Report

    SciTech Connect (OSTI)

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

    1992-03-01T23:59:59.000Z

    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.

  16. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1992-04-01T23:59:59.000Z

    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.

  17. Multiple anatomy optimization of accumulated dose

    SciTech Connect (OSTI)

    Watkins, W. Tyler, E-mail: watkinswt@virginia.edu; Siebers, Jeffrey V. [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22908 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Moore, Joseph A. [Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University, Baltimore, Maryland 21231 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Gordon, James [Henry Ford Health System, Detroit, Michigan 48202 and Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States); Hugo, Geoffrey D. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: To investigate the potential advantages of multiple anatomy optimization (MAO) for lung cancer radiation therapy compared to the internal target volume (ITV) approach. Methods: MAO aims to optimize a single fluence to be delivered under free-breathing conditions such that the accumulated dose meets the plan objectives, where accumulated dose is defined as the sum of deformably mapped doses computed on each phase of a single four dimensional computed tomography (4DCT) dataset. Phantom and patient simulation studies were carried out to investigate potential advantages of MAO compared to ITV planning. Through simulated delivery of the ITV- and MAO-plans, target dose variations were also investigated. Results: By optimizing the accumulated dose, MAO shows the potential to ensure dose to the moving target meets plan objectives while simultaneously reducing dose to organs at risk (OARs) compared with ITV planning. While consistently superior to the ITV approach, MAO resulted in equivalent OAR dosimetry at planning objective dose levels to within 2% volume in 14/30 plans and to within 3% volume in 19/30 plans for each lung V20, esophagus V25, and heart V30. Despite large variations in per-fraction respiratory phase weights in simulated deliveries at high dose rates (e.g., treating 4/10 phases during single fraction beams) the cumulative clinical target volume (CTV) dose after 30 fractions and per-fraction dose were constant independent of planning technique. In one case considered, however, per-phase CTV dose varied from 74% to 117% of prescription implying the level of ITV-dose heterogeneity may not be appropriate with conventional, free-breathing delivery. Conclusions: MAO incorporates 4DCT information in an optimized dose distribution and can achieve a superior plan in terms of accumulated dose to the moving target and OAR sparing compared to ITV-plans. An appropriate level of dose heterogeneity in MAO plans must be further investigated.

  18. Adaptive control for accelerators

    DOE Patents [OSTI]

    Eaton, Lawrie E. (Los Alamos, NM); Jachim, Stephen P. (Los Alamos, NM); Natter, Eckard F. (Santa Fe, NM)

    1991-01-01T23:59:59.000Z

    An adaptive feedforward control loop is provided to stabilize accelerator beam loading of the radio frequency field in an accelerator cavity during successive pulses of the beam into the cavity. A digital signal processor enables an adaptive algorithm to generate a feedforward error correcting signal functionally determined by the feedback error obtained by a beam pulse loading the cavity after the previous correcting signal was applied to the cavity. Each cavity feedforward correcting signal is successively stored in the digital processor and modified by the feedback error resulting from its application to generate the next feedforward error correcting signal. A feedforward error correcting signal is generated by the digital processor in advance of the beam pulse to enable a composite correcting signal and the beam pulse to arrive concurrently at the cavity.

  19. ORISE: Dose modeling and assessments

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparencyDOE ProjectCrisis and Risk CommunicationOakDose modeling

  20. Dosimetric and Radiobiological Consequences of Computed TomographyGuided Adaptive Strategies for Intensity Modulated Radiation Therapy of the Prostate

    SciTech Connect (OSTI)

    Battista, Jerry J., E-mail: j2b@uwo.ca [Department of Medical Biophysics, Western University, London, ON (Canada); Department of Oncology, Western University, London, ON (Canada); London Regional Cancer Program, London Health Sciences Centre, London, ON (Canada); Johnson, Carol; Turnbull, David; Kempe, Jeff [London Regional Cancer Program, London Health Sciences Centre, London, ON (Canada); Bzdusek, Karl [Philips Healthcare (Radiation Oncology Systems), Fitchburg, Wisconsin (United States); Van Dyk, Jacob; Bauman, Glenn [Department of Medical Biophysics, Western University, London, ON (Canada); Department of Oncology, Western University, London, ON (Canada); London Regional Cancer Program, London Health Sciences Centre, London, ON (Canada)

    2013-12-01T23:59:59.000Z

    Purpose: To examine a range of scenarios for image-guided adaptive radiation therapy of prostate cancer, including different schedules for megavoltage CT imaging, patient repositioning, and dose replanning. Methods and Materials: We simulated multifraction dose distributions with deformable registration using 35 sets of megavoltage CT scans of 13 patients. We computed cumulative dosevolume histograms, from which tumor control probabilities and normal tissue complication probabilities (NTCPs) for rectum were calculated. Five-field intensity modulated radiation therapy (IMRT) with 18-MV x-rays was planned to achieve an isocentric dose of 76 Gy to the clinical target volume (CTV). The differences between D{sub 95}, tumor control probability, V{sub 70Gy}, and NTCP for rectum, for accumulated versus planned dose distributions, were compared for different target volume sizes, margins, and adaptive strategies. Results: The CTV D{sub 95} for IMRT treatment plans, averaged over 13 patients, was 75.2 Gy. Using the largest CTV margins (10/7 mm), the D{sub 95} values accumulated over 35 fractions were within 2% of the planned value, regardless of the adaptive strategy used. For tighter margins (5 mm), the average D{sub 95} values dropped to approximately 73.0 Gy even with frequent repositioning, and daily replanning was necessary to correct this deficit. When personalized margins were applied to an adaptive CTV derived from the first 6 treatment fractions using the STAPLE (Simultaneous Truth and Performance Level Estimation) algorithm, target coverage could be maintained using a single replan 1 week into therapy. For all approaches, normal tissue parameters (rectum V{sub 70Gy} and NTCP) remained within acceptable limits. Conclusions: The frequency of adaptive interventions depends on the size of the CTV combined with target margins used during IMRT optimization. The application of adaptive target margins (<5 mm) to an adaptive CTV determined 1 week into therapy minimizes the need for subsequent dose replanning.

  1. anthropometrically derived dosing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 102 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  2. additional dose assessment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 139 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  3. absorbed gamma dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  4. atoll dose assessment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 89 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  5. absorbed dose profiles: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  6. administer therapeutic dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 133 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  7. astronaut absorbed dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  8. absorbed dose kerma: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  9. assess lung dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Morgan 68 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  10. avaliacao da dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 31 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  11. absorbed dose estimates: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NTS tests 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  12. absorbed doses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  13. absorbed doses received: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  14. absorbed radiation dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    10 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  15. average absorbed doses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  16. assessing organ doses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 140 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  17. absorbed dose optimization: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  18. afterloading high dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    71 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  19. absorbed dose estimation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    NTS tests 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  20. absorbed glandular dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  1. absorbed dose metrology: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  2. absorbed dose onboard: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  3. affecting dose distributions: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 141 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  4. absorbed doses profiles: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  5. absorbed dose appears: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  6. absorbed dose computations: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  7. absorbed dose 3d: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  8. acenocoumarol dose based: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Jonathan 48 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  9. absorbed doses onboard: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  10. absorbed dose evaluation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Index 1 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  11. Multicriteria optimization of the spatial dose distribution

    SciTech Connect (OSTI)

    Schlaefer, Alexander [Medical Robotics Group, Universitt zu Lbeck, Lbeck 23562, Germany and Institute of Medical Technology, Hamburg University of Technology, Hamburg 21073 (Germany)] [Medical Robotics Group, Universitt zu Lbeck, Lbeck 23562, Germany and Institute of Medical Technology, Hamburg University of Technology, Hamburg 21073 (Germany); Viulet, Tiberiu [Medical Robotics Group, Universitt zu Lbeck, Lbeck 23562 (Germany)] [Medical Robotics Group, Universitt zu Lbeck, Lbeck 23562 (Germany); Muacevic, Alexander; Frweger, Christoph [European CyberKnife Center Munich, Munich 81377 (Germany)] [European CyberKnife Center Munich, Munich 81377 (Germany)

    2013-12-15T23:59:59.000Z

    Purpose: Treatment planning for radiation therapy involves trade-offs with respect to different clinical goals. Typically, the dose distribution is evaluated based on few statistics and dosevolume histograms. Particularly for stereotactic treatments, the spatial dose distribution represents further criteria, e.g., when considering the gradient between subregions of volumes of interest. The authors have studied how to consider the spatial dose distribution using a multicriteria optimization approach.Methods: The authors have extended a stepwise multicriteria optimization approach to include criteria with respect to the local dose distribution. Based on a three-dimensional visualization of the dose the authors use a software tool allowing interaction with the dose distribution to map objectives with respect to its shape to a constrained optimization problem. Similarly, conflicting criteria are highlighted and the planner decides if and where to relax the shape of the dose distribution.Results: To demonstrate the potential of spatial multicriteria optimization, the tool was applied to a prostate and meningioma case. For the prostate case, local sparing of the rectal wall and shaping of a boost volume are achieved through local relaxations and while maintaining the remaining dose distribution. For the meningioma, target coverage is improved by compromising low dose conformality toward noncritical structures. A comparison of dosevolume histograms illustrates the importance of spatial information for achieving the trade-offs.Conclusions: The results show that it is possible to consider the location of conflicting criteria during treatment planning. Particularly, it is possible to conserve already achieved goals with respect to the dose distribution, to visualize potential trade-offs, and to relax constraints locally. Hence, the proposed approach facilitates a systematic exploration of the optimal shape of the dose distribution.

  12. Adapting to Survive

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1 IntroductionActinide ChemistryActivitiesAdapting to

  13. Adaptive Energy Grid

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office511041cloth DocumentationProducts (VAP) VAP7-0973 1 IntroductionActinide ChemistryActivitiesAdapting

  14. Dynamically accumulated dose and 4D accumulated dose for moving tumors

    SciTech Connect (OSTI)

    Li Heng; Li Yupeng; Zhang Xiaodong; Li Xiaoqiang; Liu Wei; Gillin, Michael T.; Zhu, X. Ronald [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2012-12-15T23:59:59.000Z

    Purpose: The purpose of this work was to investigate the relationship between dynamically accumulated dose (dynamic dose) and 4D accumulated dose (4D dose) for irradiation of moving tumors, and to quantify the dose uncertainty induced by tumor motion. Methods: The authors established that regardless of treatment modality and delivery properties, the dynamic dose will converge to the 4D dose, instead of the 3D static dose, after multiple deliveries. The bounds of dynamic dose, or the maximum estimation error using 4D or static dose, were established for the 4D and static doses, respectively. Numerical simulations were performed (1) to prove the principle that for each phase, after multiple deliveries, the average number of deliveries for any given time converges to the total number of fractions (K) over the number of phases (N); (2) to investigate the dose difference between the 4D and dynamic doses as a function of the number of deliveries for deliveries of a 'pulsed beam'; and (3) to investigate the dose difference between 4D dose and dynamic doses as a function of delivery time for deliveries of a 'continuous beam.' A Poisson model was developed to estimate the mean dose error as a function of number of deliveries or delivered time for both pulsed beam and continuous beam. Results: The numerical simulations confirmed that the number of deliveries for each phase converges to K/N, assuming a random starting phase. Simulations for the pulsed beam and continuous beam also suggested that the dose error is a strong function of the number of deliveries and/or total deliver time and could be a function of the breathing cycle, depending on the mode of delivery. The Poisson model agrees well with the simulation. Conclusions: Dynamically accumulated dose will converge to the 4D accumulated dose after multiple deliveries, regardless of treatment modality. Bounds of the dynamic dose could be determined using quantities derived from 4D doses, and the mean dose difference between the dynamic dose and 4D dose as a function of number of deliveries and/or total deliver time was also established.

  15. Irradiation of the prostate and pelvic lymph nodes with an adaptive algorithm

    SciTech Connect (OSTI)

    Hwang, A. B.; Chen, J.; Nguyen, T. B.; Gottschalk, A. G.; Roach, M. R. III; Pouliot, J. [Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, San Francisco, California 94143 (United States); Prowess Inc., Concord, California 94520 (United States); Department of Radiation Oncology, University of California San Francisco, 1600 Divisadero Street, San Francisco, California 94143 (United States)

    2012-02-15T23:59:59.000Z

    Purpose: The simultaneous treatment of pelvic lymph nodes and the prostate in radiotherapy for prostate cancer is complicated by the independent motion of these two target volumes. In this work, the authors study a method to adapt intensity modulated radiation therapy (IMRT) treatment plans so as to compensate for this motion by adaptively morphing the multileaf collimator apertures and adjusting the segment weights. Methods: The study used CT images, tumor volumes, and normal tissue contours from patients treated in our institution. An IMRT treatment plan was then created using direct aperture optimization to deliver 45 Gy to the pelvic lymph nodes and 50 Gy to the prostate and seminal vesicles. The prostate target volume was then shifted in either the anterior-posterior direction or in the superior-inferior direction. The treatment plan was adapted by adjusting the aperture shapes with or without re-optimizing the segment weighting. The dose to the target volumes was then determined for the adapted plan. Results: Without compensation for prostate motion, 1 cm shifts of the prostate resulted in an average decrease of 14% in D-95%. If the isocenter is simply shifted to match the prostate motion, the prostate receives the correct dose but the pelvic lymph nodes are underdosed by 14% {+-} 6%. The use of adaptive morphing (with or without segment weight optimization) reduces the average change in D-95% to less than 5% for both the pelvic lymph nodes and the prostate. Conclusions: Adaptive morphing with and without segment weight optimization can be used to compensate for the independent motion of the prostate and lymph nodes when combined with daily imaging or other methods to track the prostate motion. This method allows the delivery of the correct dose to both the prostate and lymph nodes with only small changes to the dose delivered to the target volumes.

  16. BRIDGING NAVIGATION, SEARCH AND ADAPTATION. Adaptive Hypermedia Models Evolution

    E-Print Network [OSTI]

    De Bra, Paul

    Corpus, Dexter Model, AHAM, GAF. Abstract: Adaptive Hypermedia Systems (AHS) have long been concentrating The most referenced (but certainly not only) Adaptive Hypermedia (AH) model dates back to 1999. Since AHAM/Hypermedia modelling from Dexter Model through AHAM to the proposed GAF model, out- line advantages of each framework

  17. Internal dose following a major nuclear war

    SciTech Connect (OSTI)

    Peterson, K.R.; Shapiro, C.S. (Lawrence Livermore National Laboratory, Livermore, CA (Unites States))

    1992-01-01T23:59:59.000Z

    The PATHWAY model results were used, in conjunction with a hypothetical major nuclear attack on the U.S., to arrive at the ratio of internal to external dose for humans from early (48 h) fallout. Considered were the four nuclides (137Cs, 89Sr, 90Sr, 131I) that account for most of the reconstructed whole-body committed equivalent dose from internal radiation in people who lived downwind of the Nevada Test Site during atmospheric tests. Effects of climate perturbations (the 'nuclear winter' effect) on food crops were considered. These could increase internal dose estimates, depending on the severity of the climate perturbations. Internal and external doses to humans for 10 locations within the U.S. have been calculated, with varying local conditions and varying assumption about their shelters. The estimated 50-y internal dose commitment ranged from 0.0-0.17 Sv, the 48-h external dose from 0.15-4.6 Sv. The resultant ratios of internal to external committed dose received in the first months (until food transport was restored) varied from less than 0.01 to about 0.2. In all cases examined, the total dose from early fallout was found to be dominated by the external dose.

  18. Hanford Environmental Dose Reconstruction Project Monthly Report

    SciTech Connect (OSTI)

    Finch, S.M. (comp.)

    1990-01-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is being managed and conducted by the Pacific Northwest Laboratory (PNL) under the direction of an independent Technical Steering Panel (TSP). 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; and environmental pathways and dose estimates. 3 figs.

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

    SciTech Connect (OSTI)

    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

    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.

  20. Determination of radionuclides and pathways contributing to cumulative dose. Hanford Environmental Dose Reconstruction Project: Dose code recovery activities, Calculation 004

    SciTech Connect (OSTI)

    Napier, B.A.

    1992-12-01T23:59:59.000Z

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 004) examined the contributions of numerous radionuclides to cumulative dose via environmental exposures and accumulation in foods. Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows` milk from Feeding Regime 1, as described in calculation 002. This calculation specifically addresses cumulative radiation doses to infants and adults resulting from releases occurring over the period 1945 through 1972.

  1. I. INTRODUCTION Hierarchical Adaptive Kalman

    E-Print Network [OSTI]

    Ghosh, Joydeep

    I. INTRODUCTION Hierarchical Adaptive Kalman Filtering for Interplanetary Orbit Determination of Texas at Austin A modular and flexibleapproach to adaptive Kalman filtering has recently been introduced using the framework of a mixture-of-experts regulated by a gating network. Each expert is a Kalman

  2. Adaptation, Learning, and Optimization over

    E-Print Network [OSTI]

    California at Los Angeles, University of

    Adaptation, Learning, and Optimization over Networks Ali H. Sayed University of California at Los 2014 A. H. Sayed DOI: 10.1561/2200000051 Adaptation, Learning, and Optimization over Networks Ali H . . . . . . . . . . . . . . . . . . . . . . . . . 7 1.6 Notation and Symbols . . . . . . . . . . . . . . . . . . . . 8 2 Optimization by Single Agents

  3. Adaptive Optics in Star Formation

    E-Print Network [OSTI]

    Wolfgang Brandner

    2003-09-29T23:59:59.000Z

    Over the past ten years, the concept of adaptive optics has evolved from early experimental stages to a standard observing tool now available at almost all major optical and near-infrared telescope facilities. Adaptive optics will also be essential in exploiting the full potential of the large optical/infrared interferometers currently under construction. Both observations with high-angular resolution and at high contrast, and with a high point source sensitivity are facilitated by adaptive optics. Among the areas which benefit most from the use of adaptive optics are studies of the circumstellar environment (envelopes, disks, outflows), substellar companions and multiple systems, and dense young stellar populations. This contribution highlights some of the recent advances in star formation studies facilitated by adaptive optics, and gives a brief tutorial on optimized observing and data reduction strategies.

  4. An updated dose assessment for Rongelap Island

    SciTech Connect (OSTI)

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

    1994-07-01T23:59:59.000Z

    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).

  5. Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny

    E-Print Network [OSTI]

    Yu, K.N.

    Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny in the human Abstract To calculate the absorbed dose in the human lung due to inhaled radon progeny, ICRP focussed and secretory cells). The absorbed energy for alpha particles emitted by radon progeny in the human respiratory

  6. Adaptive excitation control in power systems

    E-Print Network [OSTI]

    Chiu, Pei-Chen

    2006-08-16T23:59:59.000Z

    This thesis presents an adaptive excitation controller of power systems. The control law is derived by using model reference adaptive control (MRAC) or adaptive pole placement control (APPC) and an equilibrium tracking mechanism is implemented...

  7. Dose reduction at nuclear power plants

    SciTech Connect (OSTI)

    Baum, J.W.; Dionne, B.J.

    1983-01-01T23:59:59.000Z

    The collective dose equivalent at nuclear power plants increased from 1250 rem in 1969 to nearly 54,000 rem in 1980. This rise is attributable primarily to an increase in nuclear generated power from 1289 MW-y to 29,155 MW-y; and secondly, to increased average plant age. However, considerable variation in exposure occurs from plant to plant depending on plant type, refueling, maintenance, etc. In order to understand the factors influencing these differences, an investigation was initiated to study dose-reduction techniques and effectiveness of as low as reasonably achievable (ALARA) planning at light water plants. Objectives are to: identify high-dose maintenance tasks and related dose-reduction techniques; investigate utilization of high-reliability, low-maintenance equipment; recommend improved radioactive waste handling equipment and procedures; examine incentives for dose reduction; and compile an ALARA handbook.

  8. Hanford Environmental Dose Reconstruction Project Monthly Report

    SciTech Connect (OSTI)

    Finch, S.M. (comp.)

    1990-05-01T23:59:59.000Z

    This monthly report summarizes the technical progress and project status for the Hanford Environmental Dose Reconstruction (HEDR) Project being conducted at Pacific Northwest Laboratory (PNL) under the direction of a Technical Steering Panel (TSP). The TSP is composed of experts in numerous technical fields related to this project and represents the interests of the public. The US Department of Energy (DOE) funds the project. The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation doses that populations could have received from nuclear operations at Hanford since 1944. The project is divided into the following technical tasks. These tasks address each of the primary steps in the path from radioactive releases to dose estimates source terms, environmental transport, environmental monitoring data, demographics, agriculture, and food habits, and environmental pathways and dose estimates.

  9. Dose calculations for severe LWR accident scenarios

    SciTech Connect (OSTI)

    Margulies, T.S.; Martin, J.A. Jr.

    1984-05-01T23:59:59.000Z

    This report presents a set of precalculated doses based on a set of postulated accident releases and intended for use in emergency planning and emergency response. Doses were calculated for the PWR (Pressurized Water Reactor) accident categories of the Reactor Safety Study (WASH-1400) using the CRAC (Calculations of Reactor Accident Consequences) code. Whole body and thyroid doses are presented for a selected set of weather cases. For each weather case these calculations were performed for various times and distances including three different dose pathways - cloud (plume) shine, ground shine and inhalation. During an emergency this information can be useful since it is immediately available for projecting offsite radiological doses based on reactor accident sequence information in the absence of plant measurements of emission rates (source terms). It can be used for emergency drill scenario development as well.

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

    SciTech Connect (OSTI)

    Dooling, J.; Accelerator Systems Division (APS)

    2010-11-01T23:59:59.000Z

    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

  11. A Dynamic Platform for Runtime Adaptation

    E-Print Network [OSTI]

    Pham, Hubert

    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 ...

  12. Climate Change, Adaptation, and Development

    E-Print Network [OSTI]

    Cole, Daniel H.

    2008-01-01T23:59:59.000Z

    adaptive efficiency in some LDC economies. At this point,capacity-building" in LDC parties. 22 Addition- ally, twoof the over-dependence of many LDC economies on sectors that

  13. COMMENTARY:Limits to adaptation

    SciTech Connect (OSTI)

    Preston, Benjamin L [ORNL

    2013-01-01T23:59:59.000Z

    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.

  14. Adaptive multiconfigurational wave functions

    SciTech Connect (OSTI)

    Evangelista, Francesco A., E-mail: francesco.evangelista@emory.edu [Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322 (United States)

    2014-03-28T23:59:59.000Z

    A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff ?. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than ?. The resulting ?-CI wave function is adaptive, being able to represent both single-reference and multireference electronic states. We also consider a more compact wave function parameterization (?+SD-CI), which is based on a small ?-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build ?-CI wave functions. The first is based on an approximate prescreening of the full configuration interaction space, while the second performs a breadth-first search coupled with pruning. The ?-CI and ?+SD-CI approaches are used to compute the dissociation curve of N{sub 2} and the potential energy curves for the first three singlet states of C{sub 2}. Special attention is paid to the issue of energy discontinuities caused by changes in the size of the ?-CI wave function along the potential energy curve. This problem is shown to be solvable by smoothing the matrix elements of the Hamiltonian. Our last example, involving the Cu{sub 2}O{sub 2}{sup 2+} core, illustrates an alternative use of the ?-CI method: as a tool to both estimate the multireference character of a wave function and to create a compact model space to be used in subsequent high-level multireference coupled cluster computations.

  15. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1992-07-01T23:59:59.000Z

    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.

  16. Matrix adaptation in discriminative vector quantization

    E-Print Network [OSTI]

    Zachmann, Gabriel

    . Gabriel Zachmann (Computer Graphics) #12;Matrix adaptation in discriminative vector quantization Petra

  17. absorbed dose calculation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 4 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  18. absorbed dose measurements: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2013-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  19. air dose absorbed: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2009-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  20. absorbed dose distribution: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  1. absorbed dose measurement: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2013-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  2. absorbed dose determination: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2012-06-07 5 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  3. absorbed dose effective: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 2 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  4. absorbed dose standard: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 4 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  5. absorbed doses distribution: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  6. absorbed dose distributions: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  7. absorbed dose rate: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 3 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  8. absorbed dose determinations: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2012-06-07 5 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  9. absorbed dose calculations: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2010-01-01 4 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

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

    SciTech Connect (OSTI)

    Not Available

    1988-07-01T23:59:59.000Z

    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.

  11. Total ionizing dose effects of domestic SiGe HBTs under different dose rate

    E-Print Network [OSTI]

    Mo-Han, Liu; Wu-Ying, Ma; Xin, Wang; Qi, Guo; Cheng-Fa, He; Ke, Jiang; Xiao-Long, Li; Ming-Zhu, Xiong

    2015-01-01T23:59:59.000Z

    The total ionizing radiation (TID) response of commercial NPN silicon germanium hetero-junction bipolar transistors (SiGe HBTs) produced domestic were investigated under the dose rate of 800mGy(Si)/s and 1.3mGy(Si)/s with Co-60 gamma irradiation source, respectively. The changes of the transistor parameter such as Gummel characteristics, excess base current before and after irradiation are investigated. The results of the experiments shows that for the KT1151, the radiation damage have slightly difference under the different dose rate after the prolonged annealing, shows an time dependent effect(TDE). But for the KT9041, the degradations of low dose rate irradiation are more higher than the high dose rate, demonstrate that there have potential enhanced low dose rate sensitive(ELDRS) effect exist on KT9041. The underlying physical mechanisms of the different dose rates response induced by the gamma ray are detailed discussed.

  12. Journal of X-Ray Science and Technology 11 (2003) 149159 149 A preliminary study on adaptive

    E-Print Network [OSTI]

    Virginia Tech

    2003-01-01T23:59:59.000Z

    be highly effective for dose reduction in Digital Subtraction Angiography (DSA) by minimizing the field on adaptive field-of-view tracking in peripheral digital subtraction angiography James R. Bennetta,b , Er-Wei Baic , John I. Hallorand and Ge Wanga,e aCT/Micro-CT Laboratory, Department of Radiology, University

  13. Comparison of radiological dose pathways for tank farm accidents

    SciTech Connect (OSTI)

    Van Keuren, J.C.

    1996-10-30T23:59:59.000Z

    This calculation note documents an evaluation of the doses from submersion and ground shine due to a release of tank farm radioactive materials, and a comparison of these doses to the doses from inhalation of the materials. The submersion and ground shine doses are insignificant compared to the inhalation doses. The doses from resuspension are also shown to be negligible for the tank farm analysis conditions.

  14. Population estimates for Phase 1: Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Beck, D.M.; Erickson, A.R.; Harkreader, S.A.

    1992-03-01T23:59:59.000Z

    This report summarizes the population estimates of Phase I of the Hanford Environmental Dose Reconstruction (HEDR) Project. These estimates were used to develop preliminary dose estimates.

  15. Low-dose radiation impacts skin sensitivity | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Low-dose radiation impacts skin sensitivity Low-dose radiation impacts skin sensitivity Released: April 06, 2015 Systems approach suggests alterations in stability of cells and...

  16. Adaptive Radiotherapy for Locally Advanced Non-Small-Cell Lung Cancer Does Not Underdose the Microscopic Disease and has the Potential to Increase Tumor Control

    SciTech Connect (OSTI)

    Guckenberger, Matthias, E-mail: guckenberger_m@klinik.uni-wuerzburg.de [Department of Radiation Oncology, University Hospital Wuerzburg, Wuerzburg (Germany); Academic Unit of Radiotherapy and Oncology, Institute of Cancer Research, Sutton, Surrey (United Kingdom); Lung Unit, The Royal Marsden NHS Foundation Trust, Sutton, Surrey (United Kingdom); Richter, Anne; Wilbert, Juergen; Flentje, Michael [Department of Radiation Oncology, University Hospital Wuerzburg, Wuerzburg (Germany); Partridge, Mike [Joint Department of Physics, Institute of Cancer Research, Sutton, Surrey (United Kingdom)

    2011-11-15T23:59:59.000Z

    Purpose: To evaluate doses to the microscopic disease (MD) in adaptive radiotherapy (ART) for locally advanced non-small-cell lung cancer (NSCLC) and to model tumor control probability (TCP). Methods and Materials: In a retrospective planning study, three-dimensional conformal treatment plans for 13 patients with locally advanced NSCLC were adapted to shape and volume changes of the gross tumor volume (GTV) once or twice during conventionally fractionated radiotherapy with total doses of 66 Gy; doses in the ART plans were escalated using an iso-mean lung dose (MLD) approach compared to non-adapted treatment. Dose distributions to the volumes of suspect MD were simulated for a scenario with synchronous shrinkage of the MD and GTV and for a scenario of a stationary MD despite GTV shrinkage; simulations were performed using deformable image registration. TCP calculations considering doses to the GTV and MD were performed using three different models. Results: Coverage of the MD at 50 Gy was not compromised by ART. Coverage at 60 Gy in the scenario of a stationary MD was significantly reduced from 92% {+-} 10% to 73% {+-} 19% using ART; however, the coverage was restored by iso-MLD dose escalation. Dose distributions in the MD were sufficient to achieve a TCP >80% on average in all simulation experiments, with the clonogenic cell density the major factor influencing TCP. The combined TCP for the GTV and MD was 19.9% averaged over all patients and TCP models in non-adaptive treatment with 66 Gy. Iso-MLD dose escalation achieved by ART increased the overall TCP by absolute 6% (adapting plan once) and by 8.7% (adapting plan twice) on average. Absolute TCP values were significantly different between the TCP models; however, all TCP models suggested very similar TCP increase by using ART. Conclusions: Adaptation of radiotherapy to the shrinking GTV did not compromise dose coverage of volumes of suspect microscopic disease and has the potential to increase TCP by >40% compared with radiotherapy planning without ART.

  17. Adaptive Liquid Crystal Windows

    SciTech Connect (OSTI)

    Taheri, Bahman; Bodnar, Volodymyr

    2011-12-31T23:59:59.000Z

    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.

  18. Hanford Environmental Dose Reconstruction Project. Monthly report

    SciTech Connect (OSTI)

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

    1991-09-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction Project is to estimate the radiation dose that individuals and populations could have received from nuclear operations at Hanford since 1944. The project is divided into five technical tasks. These tasks correspond to the path radionuclides followed, from release to impact on humans (i.e., dose estimates). The Source Terms Task develops estimates of radioactive emissions from Hanford facilities since 1944. The Environmental Transport Task reconstructs the movements of radioactive particles from the areas of release to populations. The Environmental Monitoring Data Task assemblies, evaluates and reports historical environmental monitoring data. The Demographics, Agriculture and Food Habits Task develops the data needed to identify the populations that could have been affected by the releases. The Environmental Pathways and Dose Estimates Task used the information derived from the other Tasks to estimate the radiation doses individuals could have received from Hanford radiation. This document lists the progress on this project as of September 1991. 3 figs., 2 tabs.

  19. DRY TRANSFER FACILITY WORKER DOSE ASSESSMENT

    SciTech Connect (OSTI)

    J.S. Tang

    2004-09-23T23:59:59.000Z

    The purpose of this calculation is to estimate radiation doses received by personnel working in the Dry Transfer Facility No.1 (DTF-1) performing operations to receive transportation casks, transfer wastes, prepare waste packages, and ship out loaded waste packages and empty casks. Doses received by workers due to maintenance operations are also included in this revision. The specific scope of work contained in this calculation covers both collective doses and individual worker group doses on an annual basis, and includes the contributions due to external and internal radiation from normal operation, excluding the remediation area of the building. The results of this calculation will be used to support the design of the DTF-1 and to provide occupational dose estimates for the License Application. The calculations contained in this document were developed by Environmental and Nuclear Engineering of the Design and Engineering Organization and are intended solely for the use of the Design and Engineering Organization in its work regarding facility operation. Yucca Mountain Project personnel from the Environmental and Nuclear Engineering should be consulted before use of the calculations for purposes other than those stated herein or use by individuals other than authorized personnel in the Environmental and Nuclear Engineering.

  20. Agriculture-related radiation dose calculations

    SciTech Connect (OSTI)

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

    1987-10-01T23:59:59.000Z

    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.

  1. Low dose tomographic fluoroscopy: 4D intervention guidance with running prior

    SciTech Connect (OSTI)

    Flach, Barbara; Kuntz, Jan; Brehm, Marcus; Kachelrie, Marc [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute of Medical Physics, FriedrichAlexanderUniversity (FAU) of ErlangenNrnberg, Henkestrae 91, 91052 Erlangen (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute of Medical Physics, FriedrichAlexanderUniversity (FAU) of ErlangenNrnberg, Henkestrae 91, 91052 Erlangen (Germany); Kueres, Rolf [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg (Germany); Bartling, Snke [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute for Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, TheodorKutzerUfer 13, 68167 Mannheim (Germany)] [Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute for Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, TheodorKutzerUfer 13, 68167 Mannheim (Germany)

    2013-10-15T23:59:59.000Z

    Purpose: Today's standard imaging technique in interventional radiology is the single- or biplane x-ray fluoroscopy which delivers 2D projection images as a function of time (2D+T). This state-of-the-art technology, however, suffers from its projective nature and is limited by the superposition of the patient's anatomy. Temporally resolved tomographic volumes (3D+T) would significantly improve the visualization of complex structures. A continuous tomographic data acquisition, if carried out with today's technology, would yield an excessive patient dose. Recently the authors proposed a method that enables tomographic fluoroscopy at the same dose level as projective fluoroscopy which means that if scanning time of an intervention guided by projective fluoroscopy is the same as that of an intervention guided by tomographic fluoroscopy, almost the same dose is administered to the patient. The purpose of this work is to extend authors' previous work and allow for patient motion during the intervention.Methods: The authors propose the running prior technique for adaptation of a prior image. This adaptation is realized by a combination of registration and projection replacement. In a first step the prior is deformed to the current position via affine and deformable registration. Then the information from outdated projections is replaced by newly acquired projections using forward and backprojection steps. The thus adapted volume is the running prior. The proposed method is validated by simulated as well as measured data. To investigate motion during intervention a moving head phantom was simulated. Real in vivo data of a pig are acquired by a prototype CT system consisting of a flat detector and a continuously rotating clinical gantry.Results: With the running prior technique it is possible to correct for motion without additional dose. For an application in intervention guidance both steps of the running prior technique, registration and replacement, are necessary. Reconstructed volumes based on the running prior show high image quality without introducing new artifacts and the interventional materials are displayed at the correct position.Conclusions: The running prior improves the robustness of low dose 3D+T intervention guidance toward intended or unintended patient motion.

  2. Adaptive Optics for Large Telescopes

    SciTech Connect (OSTI)

    Olivier, S

    2008-06-27T23:59:59.000Z

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments.

  3. Adaptive Sampling in Hierarchical Simulation

    SciTech Connect (OSTI)

    Knap, J; Barton, N R; Hornung, R D; Arsenlis, A; Becker, R; Jefferson, D R

    2007-07-09T23:59:59.000Z

    We propose an adaptive sampling methodology for hierarchical multi-scale simulation. The method utilizes a moving kriging interpolation to significantly reduce the number of evaluations of finer-scale response functions to provide essential constitutive information to a coarser-scale simulation model. The underlying interpolation scheme is unstructured and adaptive to handle the transient nature of a simulation. To handle the dynamic construction and searching of a potentially large set of finer-scale response data, we employ a dynamic metric tree database. We study the performance of our adaptive sampling methodology for a two-level multi-scale model involving a coarse-scale finite element simulation and a finer-scale crystal plasticity based constitutive law.

  4. Training Adaptive Decision-Making.

    SciTech Connect (OSTI)

    Abbott, Robert G.; Forsythe, James C.

    2014-10-01T23:59:59.000Z

    Adaptive Thinking has been defined here as the capacity to recognize when a course of action that may have previously been effective is no longer effective and there is need to adjust strategy. Research was undertaken with human test subjects to identify the factors that contribute to adaptive thinking. It was discovered that those most effective in settings that call for adaptive thinking tend to possess a superior capacity to quickly and effectively generate possible courses of action, as measured using the Category Generation test. Software developed for this research has been applied to develop capabilities enabling analysts to identify crucial factors that are predictive of outcomes in fore-on-force simulation exercises.

  5. Historical river flow rates for dose calculations

    SciTech Connect (OSTI)

    Carlton, W.H.

    1991-06-10T23:59:59.000Z

    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.

  6. adaptive control algorithm: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    24 25 Next Page Last Page Topic Index 1 ON AN ADAPTIVE CONTROL ALGORITHM FOR ADAPTIVE OPTICS APPLICATIONS Mathematics Websites Summary: ON AN ADAPTIVE CONTROL ALGORITHM FOR...

  7. Adaptive nonlocal means filtering based on local noise level for CT denoising

    SciTech Connect (OSTI)

    Li, Zhoubo; Trzasko, Joshua D.; Lake, David S.; Blezek, Daniel J.; Manduca, Armando, E-mail: manduca.armando@mayo.edu [Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota 55905 (United States)] [Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota 55905 (United States); Yu, Lifeng; Fletcher, Joel G.; McCollough, Cynthia H. [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)] [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)

    2014-01-15T23:59:59.000Z

    Purpose: To develop and evaluate an image-domain noise reduction method based on a modified nonlocal means (NLM) algorithm that is adaptive to local noise level of CT images and to implement this method in a time frame consistent with clinical workflow. Methods: A computationally efficient technique for local noise estimation directly from CT images was developed. A forward projection, based on a 2D fan-beam approximation, was used to generate the projection data, with a noise model incorporating the effects of the bowtie filter and automatic exposure control. The noise propagation from projection data to images was analytically derived. The analytical noise map was validated using repeated scans of a phantom. A 3D NLM denoising algorithm was modified to adapt its denoising strength locally based on this noise map. The performance of this adaptive NLM filter was evaluated in phantom studies in terms of in-plane and cross-plane high-contrast spatial resolution, noise power spectrum (NPS), subjective low-contrast spatial resolution using the American College of Radiology (ACR) accreditation phantom, and objective low-contrast spatial resolution using a channelized Hotelling model observer (CHO). Graphical processing units (GPU) implementation of this noise map calculation and the adaptive NLM filtering were developed to meet demands of clinical workflow. Adaptive NLM was piloted on lower dose scans in clinical practice. Results: The local noise level estimation matches the noise distribution determined from multiple repetitive scans of a phantom, demonstrated by small variations in the ratio map between the analytical noise map and the one calculated from repeated scans. The phantom studies demonstrated that the adaptive NLM filter can reduce noise substantially without degrading the high-contrast spatial resolution, as illustrated by modulation transfer function and slice sensitivity profile results. The NPS results show that adaptive NLM denoising preserves the shape and peak frequency of the noise power spectrum better than commercial smoothing kernels, and indicate that the spatial resolution at low contrast levels is not significantly degraded. Both the subjective evaluation using the ACR phantom and the objective evaluation on a low-contrast detection task using a CHO model observer demonstrate an improvement on low-contrast performance. The GPU implementation can process and transfer 300 slice images within 5 min. On patient data, the adaptive NLM algorithm provides more effective denoising of CT data throughout a volume than standard NLM, and may allow significant lowering of radiation dose. After a two week pilot study of lower dose CT urography and CT enterography exams, both GI and GU radiology groups elected to proceed with permanent implementation of adaptive NLM in their GI and GU CT practices. Conclusions: This work describes and validates a computationally efficient technique for noise map estimation directly from CT images, and an adaptive NLM filtering based on this noise map, on phantom and patient data. Both the noise map calculation and the adaptive NLM filtering can be performed in times that allow integration with clinical workflow. The adaptive NLM algorithm provides effective denoising of CT data throughout a volume, and may allow significant lowering of radiation dose.

  8. BC Agriculture Climate Change Adaptation

    E-Print Network [OSTI]

    Pedersen, Tom

    BC Agriculture Climate Change Adaptation Risk + Opportunity Assessment Provincial Report executive summary #12;published March 2012 by the British Columbia Agriculture & Food Climate Action Initiative www.BCAgClimateAction.ca project funding provided by Agriculture and Agri-food Canada BC Ministry of Agriculture BC Ministry

  9. BC Agriculture Climate Change Adaptation

    E-Print Network [OSTI]

    Pedersen, Tom

    BC Agriculture Climate Change Adaptation Risk + Opportunity Assessment Provincial Report #12;published March 2012 by the British Columbia Agriculture & Food Climate Action Initiative www.BCAgClimateAction.ca project funding provided by Agriculture and Agri-food Canada BC Ministry of Agriculture BC Ministry

  10. Adaptive Noisy Clustering Michael CHICHIGNOUD

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    with respect to the Lebesgue measure. Since we observe a corrupted sample, a direct approach as the popular k-means is not suitable in this case. In this paper, we propose a noisy k-means minimization, which is based on the k-means an adaptive upper bound for a new selection rule, called ERC (Empirical Risk Comparison). This selection rule

  11. Hierarchical Adaptive Dynamic Power Management

    E-Print Network [OSTI]

    Chen, Yuanzhu Peter

    Hierarchical Adaptive Dynamic Power Management Zhiyuan Ren, Member, IEEE, Bruce H. Krogh, Fellow, IEEE, and Radu Marculescu, Member, IEEE Abstract--Dynamic power management aims at extending battery management strategies can lead to poor performance or unnecessary power consumption when there are wide

  12. Adaptive wiener image restoration kernel

    DOE Patents [OSTI]

    Yuan, Ding (Henderson, NV)

    2007-06-05T23:59:59.000Z

    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.

  13. Adaptive protection algorithm and system

    DOE Patents [OSTI]

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

    2009-04-28T23:59:59.000Z

    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.

  14. NON-MONOTONIC DOSE DEPENDENCE OF THERMOLUMINESCENCE

    E-Print Network [OSTI]

    Chen, Reuven

    Scientific Inc., Pacifica, CA, USA The thermoluminescence (TL) intensity in different materials is usually material used for archaeological and geological TL dating. Ichikawa(6) found that in gammaNON-MONOTONIC DOSE DEPENDENCE OF THERMOLUMINESCENCE R. Chen1,? , D. Lo2 and J. L. Lawless3 1 School

  15. Adapting Your Home for More Accessible Living

    E-Print Network [OSTI]

    Harris, Janie

    2007-04-27T23:59:59.000Z

    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...

  16. IIR algorithms for adaptive line enhancement

    SciTech Connect (OSTI)

    David, R.A.; Stearns, S.D.; Elliott, G.R.; Etter, D.M.

    1983-01-01T23:59:59.000Z

    We introduce a simple IIR structure for the adaptive line enhancer. Two algorithms based on gradient-search techniques are presented for adapting the structure. Results from experiments which utilized real data as well as computer simulations are provided.

  17. Final Report What Will Adaptation Cost?

    E-Print Network [OSTI]

    ..................................................................................................................26 Task 3: Estimate Costs of Implementing Adaptation Strategies ....................................................................34 Task 2: Calculate the Capital and Maintenance CostsFinal Report What Will Adaptation Cost? An Economic Framework for Coastal Community Infrastructure

  18. CLIMATE VULNERABILITY AND ADAPTATION STUDY FOR

    E-Print Network [OSTI]

    CLIMATE VULNERABILITY AND ADAPTATION STUDY FOR CALIFORNIA Legal Analysis of Barriers's California Climate Change Center JULY 2012 CEC5002012019 Prepared for: California Energy Commission to that framework that would facilitate adaptation to climate change. Since such changes may be difficult

  19. Sequential optimization through adaptive design of experiments

    E-Print Network [OSTI]

    Wang, Hungjen, 1971-

    2007-01-01T23:59:59.000Z

    This thesis considers the problem of achieving better system performance through adaptive experiments. For the case of discrete design space, I propose an adaptive One-Factor-at-A-Time (OFAT) experimental design, study its ...

  20. Total dose and dose rate models for bipolar transistors in circuit simulation.

    SciTech Connect (OSTI)

    Campbell, Phillip Montgomery; Wix, Steven D.

    2013-05-01T23:59:59.000Z

    The objective of this work is to develop a model for total dose effects in bipolar junction transistors for use in circuit simulation. The components of the model are an electrical model of device performance that includes the effects of trapped charge on device behavior, and a model that calculates the trapped charge densities in a specific device structure as a function of radiation dose and dose rate. Simulations based on this model are found to agree well with measurements on a number of devices for which data are available.

  1. Article original Adaptation digestive du lapin

    E-Print Network [OSTI]

    Boyer, Edmond

    Article original Adaptation digestive du lapin la teneur en constituants paritaux du rgime ne diffre pas d'un rgime l'autre, du fait d'une rgulation de l'nergie digestible ingre. L le rgime B. lapin / digestion / fibre / adaptation / transit Summary Digestive adaptation

  2. Formally Analyzing Adaptive Flight Control Ashish Tiwari

    E-Print Network [OSTI]

    Tiwari, Ashish

    tiwari@csl.sri.com Abstract. We formally verify a direct model-reference adaptive control (MRAC) method adaptive flight control. The main source of our model is [8] and [1]. The high-level architectureFormally Analyzing Adaptive Flight Control Ashish Tiwari SRI International Menlo Park, CA 94025

  3. Climate Change Adaptation for Local Government

    E-Print Network [OSTI]

    Pedersen, Tom

    Climate Change Adaptation for Local Government A Resource Guide June 2011 Jenny Fraser, Adaptation to Climate Change Team, Simon Fraser University #12;Page 1 of 26 Climate Change Adaptation for Local: RESOURCES THAT SUPPORT CLIMATE CHANGE ASSESSMENT 3. Past and Future Climate Change and Its Impacts 4

  4. Anisotropic Grid Adaptation for Multiple Aerodynamic Outputs

    E-Print Network [OSTI]

    Peraire, Jaime

    Anisotropic Grid Adaptation for Multiple Aerodynamic Outputs David A. Venditti and David L Anisotropic gridadaptive strategies are presented for viscous flow simulations in which the accurate estimation and Hessian-based anisotropic grid adaptation. Airfoil test cases are presented to demonstrate

  5. Adaptive security systems -- Combining expert systems with adaptive technologies

    SciTech Connect (OSTI)

    Argo, P.; Loveland, R.; Anderson, K. [and others

    1997-09-01T23:59:59.000Z

    The Adaptive Multisensor Integrated Security System (AMISS) uses a variety of computational intelligence techniques to reason from raw sensor data through an array of processing layers to arrive at an assessment for alarm/alert conditions based on human behavior within a secure facility. In this paper, the authors give an overview of the system and briefly describe some of the major components of the system. This system is currently under development and testing in a realistic facility setting.

  6. Integer Programs for High Dose Rate Brachytherapy Needle and Dose Planning that Directly Optimize Clinical Objectives

    E-Print Network [OSTI]

    Siauw, Ko-Ay Timmy

    2012-01-01T23:59:59.000Z

    radiation received by the bulb of the penis correlates withof radiation dose to the bulb of the penis in men with andavoided puncturing the penile bulb; the average number of

  7. adaptive immune regulators: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ecosystem Adaptive Management Environmental Sciences and Ecology Websites Summary: ;2 Baltic Ecosystem Adaptive Management, BEAM, r ett tvrvetenskapligt...

  8. adapter protein tsad: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ecosystem Adaptive Management Environmental Sciences and Ecology Websites Summary: ;2 Baltic Ecosystem Adaptive Management, BEAM, r ett tvrvetenskapligt...

  9. adaptive numerical treatment: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ecosystem Adaptive Management Environmental Sciences and Ecology Websites Summary: ;2 Baltic Ecosystem Adaptive Management, BEAM, r ett tvrvetenskapligt...

  10. adaptive antitumor immunity: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ecosystem Adaptive Management Environmental Sciences and Ecology Websites Summary: ;2 Baltic Ecosystem Adaptive Management, BEAM, r ett tvrvetenskapligt...

  11. adaptation azole drug: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ecosystem Adaptive Management Environmental Sciences and Ecology Websites Summary: ;2 Baltic Ecosystem Adaptive Management, BEAM, r ett tvrvetenskapligt...

  12. Mechanics and Applications of Pressure Adaptive Honeycomb

    E-Print Network [OSTI]

    Vos, Roelof

    2009-07-31T23:59:59.000Z

    calculations. In addition, I would like to express my gratitude to the undergraduate students that have helped with the preparations of the experiments: Lauren Kerth, Will Pflug, Tom O?Brien, Thomas Statsny, and Ryan Barnhart. v TABLE OF CONTENTS... and Curvature Induced by Pressure adaptive Honeycomb 55 3.2.1 Pressure adaptive Wing Section 60 3.2.2 Pressure adaptive Gurney Flap 63 3.2.3 Pressure adaptive Solid State Flap 65 3.2.4 Pressure adaptive Engine Inlet 67 vi 3.3 Actuation Sources 71 4.1 Cellular...

  13. Adaptive Stabilization of Nonlinear Stochastic Systems

    SciTech Connect (OSTI)

    Florchinger, P. [URA CNRS No. 399, Departement de Mathematiques, UFR MIM, Universite de Metz, Ile du Saulcy, F 57045 Metz Cedex (France)

    1998-07-15T23:59:59.000Z

    The purpose of this paper is to study the problem of asymptotic stabilization in probability of nonlinear stochastic differential systems with unknown parameters. With this aim, we introduce the concept of an adaptive control Lyapunov function for stochastic systems and we use the stochastic version of Artstein's theorem to design an adaptive stabilizer. In this framework the problem of adaptive stabilization of a nonlinear stochastic system is reduced to the problem of asymptotic stabilization in probability of a modified system. The design of an adaptive control Lyapunov function is illustrated by the example of adaptively quadratically stabilizable in probability stochastic differential systems.

  14. Technical Note: Contrast solution density and cross section errors in inhomogeneity-corrected dose calculation for breast balloon brachytherapy

    SciTech Connect (OSTI)

    Kim, Leonard H.; Zhang Miao; Howell, Roger W.; Yue, Ning J.; Khan, Atif J. [Department of Radiation Oncology, University of Medicine and Dentistry of New Jersey: Robert Wood Johnson Medical School and Cancer Institute of New Jersey, New Brunswick, New Jersey 08903 (United States); Department of Radiology, University of Medicine and Dentistry of New Jersey: New Jersey Medical School, Newark, New Jersey 07103 (United States); Department of Radiation Oncology, University of Medicine and Dentistry of New Jersey: Robert Wood Johnson Medical School and Cancer Institute of New Jersey, New Brunswick, New Jersey 08903 (United States)

    2013-01-15T23:59:59.000Z

    Purpose: Recent recommendations by the American Association of Physicists in Medicine Task Group 186 emphasize the importance of understanding material properties and their effect on inhomogeneity-corrected dose calculation for brachytherapy. Radiographic contrast is normally injected into breast brachytherapy balloons. In this study, the authors independently estimate properties of contrast solution that were expected to be incorrectly specified in a commercial brachytherapy dose calculation algorithm. Methods: The mass density and atomic weight fractions of a clinical formulation of radiographic contrast solution were determined using manufacturers' data. The mass density was verified through measurement and compared with the density obtained by the treatment planning system's CT calibration. The atomic weight fractions were used to determine the photon interaction cross section of the contrast solution for a commercial high-dose-rate (HDR) brachytherapy source and compared with that of muscle. Results: The density of contrast solution was 10% less than that obtained from the CT calibration. The cross section of the contrast solution for the HDR source was 1.2% greater than that of muscle. Both errors could be addressed by overriding the density of the contrast solution in the treatment planning system. Conclusions: The authors estimate the error in mass density and cross section parameters used by a commercial brachytherapy dose calculation algorithm for radiographic contrast used in a clinical breast brachytherapy practice. This approach is adaptable to other clinics seeking to evaluate dose calculation errors and determine appropriate density override values if desired.

  15. Center for Adaptive Optics* Santa Cruz,CA

    E-Print Network [OSTI]

    Grether, Gregory

    Center for Adaptive Optics* Santa Cruz,CA The Center for Adaptive Optics (CfAO) will concentrate on astronomical and vision science applications of adaptive optics and will reach out to other adaptive optics communities to share technologies. It will develop new instruments optimized for adaptive optics. Adaptive

  16. Ensuring the Availability and Reliability of Urea Dosing For...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ensuring the Availability and Reliability of Urea Dosing For On-Road and Non-Road Ensuring the Availability and Reliability of Urea Dosing For On-Road and Non-Road 2003 DEER...

  17. arteries dose reduction: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    artery Price, Paul A. 8 a 50% reduction in Prlr gene dose, provides strong evidence for PRL being the mediator Geosciences Websites Summary: a 50% reduction in Prlr gene dose,...

  18. Adaptive motion mapping in pancreatic SBRT patients using Fourier transforms

    E-Print Network [OSTI]

    Jones, Bernard L; Miften, Moyed

    2015-01-01T23:59:59.000Z

    Recent studies suggest that 4DCT is unable to accurately measure respiratory-induced pancreatic tumor motion. In this work, we assessed the daily motion of pancreatic tumors treated with SBRT, and developed adaptive strategies to predict and account for this motion. The daily motion trajectory of pancreatic tumors during CBCT acquisition was calculated using a model which reconstructs the instantaneous 3D position in each 2D CBCT projection image. We developed a metric (termed "Spectral Coherence," SC) based on the Fourier frequency spectrum of motion in the SI direction, and analyzed the ability of SC to predict motion-based errors and classify patients according to motion characteristics. The amplitude of daily motion exceeded the predictions of pre-treatment 4DCT imaging by an average of 3.0 mm, 2.3 mm, and 3.5 mm in the AP, LR, and SI directions. SC was correlated with daily motion differences and tumor dose coverage. In a simulated adaptive protocol, target margins were adjusted based on SC, resulting in...

  19. Adapting Dry Cask Storage for Aging at a Geologic Repository

    SciTech Connect (OSTI)

    C. Sanders; D. Kimball

    2005-08-02T23:59:59.000Z

    A Spent Nuclear Fuel (SNF) Aging System is a crucial part of operations at the proposed Yucca Mountain repository in the United States. Incoming commercial SNF that does not meet thermal limits for emplacement will be aged on outdoor pads. U.S. Department of Energy SNF will also be managed using the Aging System. Proposed site-specific designs for the Aging System are closely based upon designs for existing dry cask storage (DCS) systems. This paper evaluates the applicability of existing DCS systems for use in the SNF Aging System at Yucca Mountain. The most important difference between existing DCS facilities and the Yucca Mountain facility is the required capacity. Existing DCS facilities typically have less than 50 casks. The current design for the aging pad at Yucca Mountain calls for a capacity of over 2,000 casks (20,000 MTHM) [1]. This unprecedented number of casks poses some unique problems. The response of DCS systems to off-normal and accident conditions needs to be re-evaluated for multiple storage casks. Dose calculations become more complicated, since doses from multiple or very long arrays of casks can dramatically increase the total boundary dose. For occupational doses, the geometry of the cask arrays and the order of loading casks must be carefully considered in order to meet ALARA goals during cask retrieval. Due to the large area of the aging pad, skyshine must also be included when calculating public and worker doses. The expected length of aging will also necessitate some design adjustments. Under 10 CFR 72.236, DCS systems are initially certified for a period of 20 years [2]. Although the Yucca Mountain facility is not intended to be a storage facility under 10 CFR 72, the operational life of the SNF Aging System is 50 years [1]. Any cask system selected for use in aging will have to be qualified to this design lifetime. These considerations are examined, and a summary is provided of the adaptations that must be made in order to use DCS technologies successfully at a geologic repository.

  20. Hanford Environmental Dose Reconstruction Project monthly report, February 1993

    SciTech Connect (OSTI)

    Cannon, S.D.; Finch, S.M. (comps.)

    1993-01-01T23:59:59.000Z

    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 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.

  1. Hanford Environmental Dose Reconstruction Project monthly report, February 1993

    SciTech Connect (OSTI)

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

    1993-03-01T23:59:59.000Z

    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 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.

  2. Hanford Environmental Dose Reconstruction Project. Monthly report, November 1991

    SciTech Connect (OSTI)

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

    1991-12-31T23:59:59.000Z

    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.

  3. Hanford Environmental Dose Reconstruction Project monthly report, May 1992

    SciTech Connect (OSTI)

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

    1992-08-01T23:59:59.000Z

    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 task 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.

  4. Hanford Environmental Dose Reconstruction Project monthly report, May 1992

    SciTech Connect (OSTI)

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

    1992-01-01T23:59:59.000Z

    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 task 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.

  5. Limitations of the TG-43 formalism for skin high-dose-rate brachytherapy dose calculations

    SciTech Connect (OSTI)

    Granero, Domingo, E-mail: dgranero@eresa.com [Department of Radiation Physics, ERESA, Hospital General Universitario, 46014 Valencia (Spain)] [Department of Radiation Physics, ERESA, Hospital General Universitario, 46014 Valencia (Spain); Perez-Calatayud, Jose [Radiotherapy Department, La Fe University and Polytechnic Hospital, Valencia 46026 (Spain)] [Radiotherapy Department, La Fe University and Polytechnic Hospital, Valencia 46026 (Spain); Vijande, Javier [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100, Spain and IFIC (UV-CSIC), Paterna 46980 (Spain)] [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100, Spain and IFIC (UV-CSIC), Paterna 46980 (Spain); Ballester, Facundo [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain)] [Department of Atomic, Molecular and Nuclear Physics, University of Valencia, Burjassot 46100 (Spain); Rivard, Mark J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)] [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2014-02-15T23:59:59.000Z

    Purpose: In skin high-dose-rate (HDR) brachytherapy, sources are located outside, in contact with, or implanted at some depth below the skin surface. Most treatment planning systems use the TG-43 formalism, which is based on single-source dose superposition within an infinite water medium without accounting for the true geometry in which conditions for scattered radiation are altered by the presence of air. The purpose of this study is to evaluate the dosimetric limitations of the TG-43 formalism in HDR skin brachytherapy and the potential clinical impact. Methods: Dose rate distributions of typical configurations used in skin brachytherapy were obtained: a 5 cm 5 cm superficial mould; a source inside a catheter located at the skin surface with and without backscatter bolus; and a typical interstitial implant consisting of an HDR source in a catheter located at a depth of 0.5 cm. Commercially available HDR{sup 60}Co and {sup 192}Ir sources and a hypothetical {sup 169}Yb source were considered. The Geant4 Monte Carlo radiation transport code was used to estimate dose rate distributions for the configurations considered. These results were then compared to those obtained with the TG-43 dose calculation formalism. In particular, the influence of adding bolus material over the implant was studied. Results: For a 5 cm 5 cm{sup 192}Ir superficial mould and 0.5 cm prescription depth, dose differences in comparison to the TG-43 method were about ?3%. When the source was positioned at the skin surface, dose differences were smaller than ?1% for {sup 60}Co and {sup 192}Ir, yet ?3% for {sup 169}Yb. For the interstitial implant, dose differences at the skin surface were ?7% for {sup 60}Co, ?0.6% for {sup 192}Ir, and ?2.5% for {sup 169}Yb. Conclusions: This study indicates the following: (i) for the superficial mould, no bolus is needed; (ii) when the source is in contact with the skin surface, no bolus is needed for either {sup 60}Co and {sup 192}Ir. For lower energy radionuclides like {sup 169}Yb, bolus may be needed; and (iii) for the interstitial case, at least a 0.1 cm bolus is advised for {sup 60}Co to avoid underdosing superficial target layers. For {sup 192}Ir and {sup 169}Yb, no bolus is needed. For those cases where no bolus is needed, its use might be detrimental as the lack of radiation scatter may be beneficial to the patient, although the 2% tolerance for dose calculation accuracy recommended in the AAPM TG-56 report is not fulfilled.

  6. Stereoscopic Interpretation of Low-Dose Breast Tomosynthesis Projection Images

    E-Print Network [OSTI]

    Bovik, Alan

    Stereoscopic Interpretation of Low-Dose Breast Tomosynthesis Projection Images Gautam S. Muralidhar of this study was to evaluate stereoscopic perception of low-dose breast tomosynthesis projection images . 3D perception . Low-dose projections Background In breast tomosynthesis imaging, 1530 x

  7. Real-time Molecular Study of Bystander Effects of Low dose Low LET radiation Using Living Cell Imaging and Nanoparticale Optics

    SciTech Connect (OSTI)

    Natarajan, Mohan [UT Health Science Center at San Antonio; Xu, Nancy R [Old Dominion University; Mohan, Sumathy [UT Health Science Center at San Antonio

    2013-06-03T23:59:59.000Z

    In this study two novel approaches are proposed to investigate precisely the low dose low LET radiation damage and its effect on bystander cells in real time. First, a flow shear model system, which would provide us a near in vivo situation where endothelial cells in the presence of extra cellular matrix experiencing continuous flow shear stress, will be used. Endothelial cells on matri-gel (simulated extra cellular matrix) will be subjected to physiological flow shear (that occurs in normal blood vessels). Second, a unique tool (Single nano particle/single live cell/single molecule microscopy and spectroscopy; Figure A) will be used to track the molecular trafficking by single live cell imaging. Single molecule chemical microscopy allows one to single out and study rare events that otherwise might be lost in assembled average measurement, and monitor many target single molecules simultaneously in real-time. Multi color single novel metal nanoparticle probes allow one to prepare multicolor probes (Figure B) to monitor many single components (events) simultaneously and perform multi-complex analysis in real-time. These nano-particles resist to photo bleaching and hence serve as probes for unlimited timeframe of analysis. Single live cell microscopy allows one to image many single cells simultaneously in real-time. With the combination of these unique tools, we will be able to study under near-physiological conditions the cellular and sub-cellular responses (even subtle changes at one molecule level) to low and very low doses of low LET radiation in real time (milli-second or nano-second) at sub-10 nanometer spatial resolution. This would allow us to precisely identify, at least in part, the molecular mediators that are responsible of radiation damage in the irradiated cells and the mediators that are responsible for initiating the signaling in the neighboring cells. Endothelial cells subjected to flow shear (2 dynes/cm2 or 16 dynes/cm2) and exposed to 0.1, 1 and 10 cGy on coverslips will be examined for (a) low LET radiation-induced alterations of cellular function and its physiological relevance in real time; and (b) radiation damage triggered bystander effect on the neighboring unirradiated cells. First, to determine the low LET radiation induced alteration of cellular function we will examine: (i) the real time transformation of single membrane transporters in single living cells; (ii) the pump efficiency of membrane efflux pump of live cells in real time at the molecular level; (iii) the kinetics of single-ligand receptor interaction on single live cell surface (Figure C); and (iv) alteration in chromosome replication in living cell. Second, to study the radiation triggered bystander responses, we will examine one of the key signaling pathway i.e. TNF- alpha/NF-kappa B mediated signaling. TNF-alpha specific nano particle sensors (green) will be developed to detect the releasing dynamics, transport mechanisms and ligand-receptor binding on live cell surface in real time. A second sensor (blue) will be developed to simultaneously monitor the track of NF-kB inside the cell. The proposed nano-particle optics approach would complement our DOE funded study on biochemical mechanisms of TNF-alpha- NF-kappa B-mediated bystander effect.

  8. Issues in adaptive mesh refinement

    SciTech Connect (OSTI)

    Dai, William Wenlong [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    In this paper, we present an approach for a patch-based adaptive mesh refinement (AMR) for multi-physics simulations. The approach consists of clustering, symmetry preserving, mesh continuity, flux correction, communications, and management of patches. Among the special features of this patch-based AMR are symmetry preserving, efficiency of refinement, special implementation offlux correction, and patch management in parallel computing environments. Here, higher efficiency of refinement means less unnecessarily refined cells for a given set of cells to be refined. To demonstrate the capability of the AMR framework, hydrodynamics simulations with many levels of refinement are shown in both two- and three-dimensions.

  9. Low-Dose Radiotherapy in Indolent Lymphoma

    SciTech Connect (OSTI)

    Rossier, Christine [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Schick, Ulrike; Miralbell, Raymond [Department of Radiation Oncology, University Hospital of Geneva (Switzerland); Mirimanoff, Rene O. [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland); Weber, Damien C. [Department of Radiation Oncology, University Hospital of Geneva (Switzerland); Ozsahin, Mahmut, E-mail: Esat-Mahmut.Ozsahin@chuv.ch [Department of Radiation Oncology, Centre Hospitalier Universitaire Vaudois, Lausanne (Switzerland)

    2011-11-01T23:59:59.000Z

    Purpose: To assess the response rate, duration of response, and overall survival after low-dose involved-field radiotherapy in patients with recurrent low-grade lymphoma or chronic lymphocytic leukemia (CLL). Methods and Materials: Forty-three (24 women, 19 men) consecutive patients with indolent lymphoma or CLL were treated with a total dose of 4 Gy (2 x 2 Gy) using 6- 18-MV photons. The median age was 73 years (range, 39-88). Radiotherapy was given either after (n = 32; 75%) or before (n = 11; 25%) chemotherapy. The median time from diagnosis was 48 months (range, 1-249). The median follow-up period was 20 months (range, 1-56). Results: The overall response rate was 90%. Twelve patients (28%) had a complete response, 15 (35%) had a partial response, 11 (26%) had stable disease, and 5 (11%) had progressive disease. The median overall survival for patients with a positive response (complete response/partial response/stable disease) was 41 months; for patients with progressive disease it was 6 months (p = 0.001). The median time to in-field progression was 21 months (range, 0-24), and the median time to out-field progression was 8 months (range, 0-40). The 3-year in-field control was 92% in patients with complete response (median was not reached). The median time to in-field progression was 9 months (range, 0.5-24) in patients with partial response and 6 months (range, 0.6-6) in those with stable disease (p < 0.05). Younger age, positive response to radiotherapy, and no previous chemotherapy were the best factors influencing the outcome. Conclusions: Low-dose involved-field radiotherapy is an effective treatment in the management of patients with recurrent low-grade lymphoma or CLL.

  10. Calculation of external dose from distributed source

    SciTech Connect (OSTI)

    Kocher, D.C.

    1986-01-01T23:59:59.000Z

    This paper discusses a relatively simple calculational method, called the point kernel method (Fo68), for estimating external dose from distributed sources that emit photon or electron radiations. The principles of the point kernel method are emphasized, rather than the presentation of extensive sets of calculations or tables of numerical results. A few calculations are presented for simple source geometries as illustrations of the method, and references and descriptions are provided for other caluclations in the literature. This paper also describes exposure situations for which the point kernel method is not appropriate and other, more complex, methods must be used, but these methods are not discussed in any detail.

  11. ORISE: Radiation Dose Estimates and Other Compendia

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC)Integrated CodesTransparencyDOENurse Triage LinesCytogeneticHowResponseDose Estimates

  12. INPUT CONSTRAINED ADAPTIVE TRACKING WITH APPLICATIONS TO

    E-Print Network [OSTI]

    Knobloch,Jrgen

    as models in several industries including continuous polymerization reactors, distillation columns tracking ac- curacy, quantified by > 0 set by the designer, is ensured. The adaptive control strategy does

  13. Training for Climate Adaptation in Conservation

    Broader source: Energy.gov [DOE]

    The Wildlife Conservation Society and the Northern Institute of Applied Climate Science are hosting this two-day training for climate adaptation.

  14. Protein Structure Suggests Role as Molecular Adapter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Protein Structure Suggests Role as Molecular Adapter Print To split and copy DNA during replication, all cellular organisms use a multicomponent molecular machine known as the...

  15. Optimization Online - An Adaptive Unified Differential Evolution ...

    E-Print Network [OSTI]

    Ji Qiang

    2015-02-19T23:59:59.000Z

    Feb 19, 2015 ... Abstract: In this paper, we propose a new adaptive unified differential evolution algorithm for single-objective global optimization. Instead of the...

  16. GLOBAL AND ADAPTIVE SCALING IN A SEPARABLE ...

    E-Print Network [OSTI]

    2007-10-19T23:59:59.000Z

    programs confirm that Adaptive Global Scaling subsumes former scaling ...... Then, the compact convex set B of symmetric matrices eigeinvalues of which.

  17. Mainstreaming Climate Change Adaptation into Development Planning...

    Open Energy Info (EERE)

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

  18. 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...

  19. Misonidazole with dexamethasone rescue: an escalating dose toxicity study

    SciTech Connect (OSTI)

    Tanasichuk, H.; Urtasun, R.C.; Fulton, D.S.; Raleigh, J.

    1984-09-01T23:59:59.000Z

    Neurotoxicity induced by misonidazole (MISO) and desmethylmisonidazole (DMM) has become the dose limiting factor in clinical work. In 1981, the authors reported a preliminary study suggestive that Dexamethasone (DEXA) does have a protective effect against peripheral neuropathies (PN) resulting from toxicity of misonidazole. The authors are presently investigating the use of DEXA, with escalating doses of MISO in an attempt to modify its neurotoxicity. To date, 16 patients have been registered to receive total doses of MISO given in 9 equally divided doses over 3 weeks. DEXA is given 3 days prior to the first dose and continues for the duration of therapy. All patients receive palliative radiation. No toxicity was seen at the total dose of 13.5 gm/M/sub 2/. One grade I PN occurred in the first four patients receiving 15.5 gm/M/sub 2/. Six additional patients were entered at this dose level and no further incidence of PN was observed.

  20. a-bisabolol induces dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    42 Absorbed dose in target cell nuclei and dose conversion coefficient of radon progeny Biology and Medicine Websites Summary: Absorbed dose in target cell nuclei and...

  1. adaptive-influence-matrix adaptive optics: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    adaptive-influence-matrix adaptive optics First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Adaptive...

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

    E-Print Network [OSTI]

    Brenner, David Jonathan

    of the radiation risks they are trying to control. ? 2012 ICRP. Published by Elsevier Ltd. All rights reserved Effective dose (ICRP, 1977) represents an attempt to provide a quantity which is proportional of the International Commission on Radiological Protection. 124 #12;and hereditary effects. Specifically, it is the sum

  3. Downhole tool adapted for telemetry

    DOE Patents [OSTI]

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

    2010-12-14T23:59:59.000Z

    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.

  4. An adaptive radiation model for the origin of new gene functions

    E-Print Network [OSTI]

    Francino, M. Pilar

    2005-01-01T23:59:59.000Z

    An adaptive radiation model for the origin of new genePreadaptation Adaptive radiation Competition among closefor a specific niche Adaptive radiation model Adaptive gene

  5. E-Print Network 3.0 - adaptive systems theory Sample Search Results

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    systems theory Page: << < 1 2 3 4 5 > >> 1 From Adaptive Hypermedia to the Adaptive Web Systems Summary: 1 From Adaptive Hypermedia to the Adaptive Web Systems Peter...

  6. ORIGINAL ARTICLE Mitigation needs adaptation: Tropical forestry

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ORIGINAL ARTICLE Mitigation needs adaptation: Tropical forestry and climate change Manuel R adapt to this change. This paper discusses how tropical forestry practices can contribute to maintaining Forestry Research, P.O. Box 6596 JKPWB, Jakarta 10065, Indonesia e-mail: m.guariguata@cgiar.org J. P

  7. OPTIMAL CONTROL WITH ADAPTIVE INTERNAL DYNAMICS MODELS

    E-Print Network [OSTI]

    Vijayakumar, Sethu

    . The optimal feedback control law for systems with non-linear dynamics and non-quadratic costs can be foundOPTIMAL CONTROL WITH ADAPTIVE INTERNAL DYNAMICS MODELS Djordje Mitrovic, Stefan Klanke, and Sethu, optimal control, adaptive control, robot simulation Abstract: Optimal feedback control has been proposed

  8. Adaptive Web Sites: Automatically Synthesizing Web Pages

    E-Print Network [OSTI]

    Etzioni, Oren

    Adaptive Web Sites: Automatically Synthesizing Web Pages Mike Perkowitz Oren Etzioni Department interfaces Abstract The creation of a complex web site is a thorny problem in user interface design. In IJCAI '97, we challenged the AI community to address this problem by creating adaptive web sites: sites

  9. General Adaptive Replacement Policies Yannis Smaragdakis

    E-Print Network [OSTI]

    Smaragdakis, Yannis

    General Adaptive Replacement Policies Yannis Smaragdakis College of Computing Georgia Institute of Technology yannis@cc.gatech.edu ABSTRACT We propose a general scheme for creating adaptive replace- ment any two existing replacement policies so that the resulting policy provably can never perform worse

  10. ADAPTIVE MULTIMEDIA TRANSMISSION OVER THE INTERNET

    E-Print Network [OSTI]

    Bouras, Christos

    Chapter 20 ADAPTIVE MULTIMEDIA TRANSMISSION OVER THE INTERNET CHRISTOS BOURAS and APOSTOLOS GKAMAS that are available to multimedia applications can be modified very quickly. Multimedia applications must have to multimedia applications, we can use techniques both at the network and application layers. Adaptive

  11. Adaptive Communication Agent for Group Communication activities

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    , limited energy resources), system execute adaptive mechanisms by monitoring the data flow. Also, the actor-wide collaborative environment, managing the adaptive communication is a challenging task. It implies the monitoring and executed without manual intervention. This research is applied to a Crisis Management System (CMS) within

  12. Enabling Informed Adaptation of Reformed Instructional Materials

    E-Print Network [OSTI]

    Elby, Andy

    Enabling Informed Adaptation of Reformed Instructional Materials Rachel E. Scherr and Andrew Elby 20742 USA Abstract. Instructors inevitably need to adapt even the best reform materials to suit instructors, and video clips of students working on the materials. Our materials thus facilitate their own

  13. Adaptive Filtering of Multilingual Document Streams

    E-Print Network [OSTI]

    Oard, Doug

    the volume of new documents that must be examined by the user to manageable levels. This paper presents three techniques for extending adaptive monolingual text ltering techniques to manage multilingual document streamsAdaptive Filtering of Multilingual Document Streams Douglas W. Oard College of Library

  14. DAMS: Distributed Adaptive Metaheuristic Selection Bilel Derbel

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    DAMS: Distributed Adaptive Metaheuristic Selection Bilel Derbel Universit Lille 1 LIFL CNRS Metaheuristic Selection (DAMS) frame- work. DAMS is dedicated to adaptive optimization in distributed environments. Given a set of metaheuristics, the goal of DAMS is to coordinate their local execution

  15. A fuzzy-tuned adaptive Kalman filter

    E-Print Network [OSTI]

    Painter, John H.; Young Hwan Lho

    1993-12-01T23:59:59.000Z

    In this paper, fuzzy processing is applied to the adaptive Kalman filter. The filter gain coefficients are adapted over a 50 dB range of unknown signal/noise dynamics, using fuzzy membership functions. Specific simulation results are shown for a...

  16. Outreach and Adaptive Strategies for Climate Change

    E-Print Network [OSTI]

    Outreach and Adaptive Strategies for Climate Change: The Role of NOAA Sea Grant Extension years and generations about how to adapt to a changing climate. Effective preparation for possible effects of climate change includes engagement of resource managers, planners, public works officials

  17. A fuzzy-tuned adaptive Kalman filter

    E-Print Network [OSTI]

    Painter, John H.; Young Hwan Lho

    1993-12-01T23:59:59.000Z

    In this paper, fuzzy processing is applied to the adaptive Kalman filter. The filter gain coefficients are adapted over a 50 dB range of unknown signal/noise dynamics, using fuzzy membership functions. Specific simulation results are shown for a...

  18. Occupational dose estimates for a monitored retrievable storage facility

    SciTech Connect (OSTI)

    Harty, R.; Stoetzel, G.A.

    1986-06-01T23:59:59.000Z

    Occupational doses were estimated for radiation workers at the monitored retrievable storage (MRS) facility. This study provides an estimate of the occupational dose based on the current MRS facility design, examines the extent that various design parameters and assumptions affect the dose estimates, and identifies the areas and activities where exposures can be reduced most effectively. Occupational doses were estimated for both the primary storage concept and the alternate storage concept. The dose estimates indicate the annual dose to all radiation workers will be below the 5 rem/yr federal dose equivalent limit. However, the estimated dose to most of the receiving and storage crew (the workers responsible for the receipt, storage, and surveillance of the spent fuel and its subsequent retrieval), to the crane maintenance technicians, and to the cold and remote maintenance technicians is above the design objective of 1 rem/yr. The highest annual dose is received by the riggers (4.7 rem) in the receiving and storage crew. An indication of the extent to which various design parameters and assumptions affect the dose estimates was obtained by changing various design-based assumptions such as work procedures, background dose rates in radiation zones, and the amount of fuel received and stored annually. The study indicated that a combination of remote operations, increased shielding, and additional personnel (for specific jobs) or changes in operating procedures will be necessary to reduce worker doses below 1.0 rem/yr. Operations that could be made at least partially remote include the removal and replacement of the tiedowns, impact limiters, and personnel barriers from the shipping casks and the removal or installation of the inner closure bolts. Reductions of the background dose rates in the receiving/shipping and the transfer/discharge areas may be accomplished with additional shielding.

  19. Shared Dosimetry Error in Epidemiological Dose-Response Analyses

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Stram, Daniel O.; Preston, Dale L.; Sokolnikov, Mikhail; Napier, Bruce; Kopecky, Kenneth J.; Boice, John; Beck, Harold; Till, John; Bouville, Andre; Zeeb, Hajo

    2015-03-23T23:59:59.000Z

    Radiation dose reconstruction systems for large-scale epidemiological studies are sophisticated both in providing estimates of dose and in representing dosimetry uncertainty. For example, a computer program was used by the Hanford Thyroid Disease Study to provide 100 realizations of possible dose to study participants. The variation in realizations reflected the range of possible dose for each cohort member consistent with the data on dose determinates in the cohort. Another example is the Mayak Worker Dosimetry System 2013 which estimates both external and internal exposures and provides multiple realizations of "possible" dose history to workers given dose determinants. This paper takesmoreup the problem of dealing with complex dosimetry systems that provide multiple realizations of dose in an epidemiologic analysis. In this paper we derive expected scores and the information matrix for a model used widely in radiation epidemiology, namely the linear excess relative risk (ERR) model that allows for a linear dose response (risk in relation to radiation) and distinguishes between modifiers of background rates and of the excess risk due to exposure. We show that treating the mean dose for each individual (calculated by averaging over the realizations) as if it was true dose (ignoring both shared and unshared dosimetry errors) gives asymptotically unbiased estimates (i.e. the score has expectation zero) and valid tests of the null hypothesis that the ERR slope ? is zero. Although the score is unbiased the information matrix (and hence the standard errors of the estimate of ?) is biased for ?60 when ignoring errors in dose estimates, and we show how to adjust the information matrix to remove this bias, using the multiple realizations of dose. The use of these methods in the context of several studies including, the MayakWorker Cohort, and the U.S. Atomic Veterans Study, is discussed.less

  20. Radiation induces turbulence in particle-laden fluids

    SciTech Connect (OSTI)

    Zamansky, Rmi [Centre for Turbulence Research, Stanford University, Stanford, California 94305-3035 (United States); Coletti, Filippo [Mechanical Engineering, Stanford University, California 94305-3035 (United States); Massot, Marc [Centre for Turbulence Research, Stanford University, Stanford, California 94305-3035 (United States); Ecole Centrale Paris, Laboratoire EM2C - UPR CNRS 288 et Fdration de Mathmatiques - FR CNRS 3487, Grande Voie des Vignes, 92295 Chatenay-Malabry Cedex (France); Mani, Ali [Centre for Turbulence Research, Stanford University, Stanford, California 94305-3035 (United States); Mechanical Engineering, Stanford University, California 94305-3035 (United States)

    2014-07-15T23:59:59.000Z

    When a transparent fluid laden with solid particles is subject to radiative heating, non-uniformities in particle distribution result in local fluid temperature fluctuations. Under the influence of gravity, buoyancy induces vortical fluid motion which can lead to strong preferential concentration, enhancing the local heating and more non-uniformities in particle distribution. By employing direct numerical simulations this study shows that the described feedback loop can create and sustain turbulence. The velocity and length scale of the resulting turbulence is not known a priori, and is set by balance between viscous forces and buoyancy effects. When the particle response time is comparable to a viscous time scale, introduced in our analysis, the system exhibits intense fluctuations of turbulent kinetic energy and strong preferential concentration of particles.

  1. Modeling progression in radiation-induced lung adenocarcinomas

    E-Print Network [OSTI]

    Fakir, Hatim; Hofmann, Werner; Sachs, Rainer K.

    2010-01-01T23:59:59.000Z

    carrying capacity. Indeed, Speer et al. (1984) showed thatdata for tumor growth (Speer et al. 1984). In our study,model. Math Biosci Speer JF, Petrosky VE, Retsky MW,

  2. Radiation-induced mechanical property changes in filled rubber

    SciTech Connect (OSTI)

    Maiti, A.; Weisgraber, T. H.; Gee, R. H.; Small, W.; Alviso, C. T.; Chinn, S. C.; Maxwell, R. S. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States)

    2011-06-15T23:59:59.000Z

    In a recent paper we exposed a filled elastomer to controlled radiation dosages and explored changes in its cross-link density and molecular weight distribution between network junctions [A. Maiti et al., Phys. Rev. E 83, 031802 (2011)]. Here we report mechanical response measurements when the material is exposed to radiation while being under finite nonzero strain. We observe interesting hysteretic behavior and material softening representative of the Mullins effect, and materials hardening due to radiation. The net magnitude of the elastic modulus depends upon the radiation dosage, strain level, and strain-cycling history of the material. Using the framework of Tobolsky's two-stage independent network theory we develop a model that can quantitatively interpret the observed elastic modulus and its radiation and strain dependence.

  3. accidental radiation-induced hematopoietic: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    solar and atmospheric neutrino oscillation, some of them can also induce neutrinoless double beta decay and mu- -- e+ conversion in nuclei large enough to be potentially...

  4. alleviates radiation-induced degeneration: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    solar and atmospheric neutrino oscillation, some of them can also induce neutrinoless double beta decay and mu- -- e+ conversion in nuclei large enough to be potentially...

  5. acute radiation-induced proctosigmoiditis: Topics by E-print...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    solar and atmospheric neutrino oscillation, some of them can also induce neutrinoless double beta decay and mu- -- e+ conversion in nuclei large enough to be potentially...

  6. abnormalities radiation-induced: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    solar and atmospheric neutrino oscillation, some of them can also induce neutrinoless double beta decay and mu- -- e+ conversion in nuclei large enough to be potentially...

  7. Validation of Dose Calculation Codes for Clearance

    SciTech Connect (OSTI)

    Menon, S.; Wirendal, B.; Bjerler, J.; Studsvik; Teunckens, L.

    2003-02-27T23:59:59.000Z

    Various international and national bodies such as the International Atomic Energy Agency, the European Commission, the US Nuclear Regulatory Commission have put forward proposals or guidance documents to regulate the ''clearance'' from regulatory control of very low level radioactive material, in order to allow its recycling as a material management practice. All these proposals are based on predicted scenarios for subsequent utilization of the released materials. The calculation models used in these scenarios tend to utilize conservative data regarding exposure times and dose uptake as well as other assumptions as a safeguard against uncertainties. None of these models has ever been validated by comparison with the actual real life practice of recycling. An international project was organized in order to validate some of the assumptions made in these calculation models, and, thereby, better assess the radiological consequences of recycling on a practical large scale.

  8. Geometric interpretation of the dose distribution comparison technique: Interpolation-free calculation

    E-Print Network [OSTI]

    Ju, Tao

    Geometric interpretation of the dose distribution comparison technique: Interpolation investigators to quantitatively compare multidimensional dose distributions. The tool requires the specification of dose and distance-to- agreement DTA criteria for acceptable variations between the dose distributions

  9. Probing young massive clusters with laser guide star adaptive optics

    E-Print Network [OSTI]

    McCrady, Nate

    2009-01-01T23:59:59.000Z

    laser guide star adaptive optics Nate McCrady Received: 10laser guide star adaptive optics (LGS/AO) on the 10 m Keckof 4 Mpc. Our adaptive optics work is motivated by three

  10. Technical Review of SRS Dose Reconstrruction Methods Used By CDC

    SciTech Connect (OSTI)

    Simpkins, Ali, A

    2005-07-20T23:59:59.000Z

    At the request of the Centers for Disease Control and Prevention (CDC), a subcontractor Advanced Technologies and Laboratories International, Inc.(ATL) issued a draft report estimating offsite dose as a result of Savannah River Site operations for the period 1954-1992 in support of Phase III of the SRS Dose Reconstruction Project. The doses reported by ATL differed than those previously estimated by Savannah River Site SRS dose modelers for a variety of reasons, but primarily because (1) ATL used different source terms, (2) ATL considered trespasser/poacher scenarios and (3) ATL did not consistently use site-specific parameters or correct usage parameters. The receptors with the highest dose from atmospheric and liquid pathways were within about a factor of four greater than dose values previously reported by SRS. A complete set of technical comments have also been included.

  11. Further evaluation of dose estimation using the FBX dosimeter

    E-Print Network [OSTI]

    Helfinstine, Suzanne Yvette

    1988-01-01T23:59:59.000Z

    offset and general discrep- ancy between the expected dose and the one measured by the FBX dosimeter. To determine the origin of these anomalies, the dosimeter was used in intimate mixtures with tritiated water, HTO, iodine crystals, and various dilute... iodine solutions. When mixed with HTO, the doses measured by the FBX solution were in better agree- ment with the doses predicted by MIRD techniques than the measurements with I. In 131 subsequent mixtures with stable iodine crystals, the dosimeter...

  12. Radiation dose rates from UF{sub 6} cylinders

    SciTech Connect (OSTI)

    Friend, P.J. [Urenco, Capenhurst (United Kingdom)

    1991-12-31T23:59:59.000Z

    This paper describes the results of many studies, both theoretical and experimental, which have been carried out by Urenco over the last 15 years into radiation dose rates from uranium hexafluoride (UF{sub 6}) cylinders. The contents of the cylinder, its history, and the geometry all affect the radiation dose rate. These factors are all examined in detail. Actual and predicted dose rates are compared with levels permitted by IAEA transport regulations.

  13. SU-E-J-245: Is Off-Line Adaptive Radiotherapy Sufficient for Head and Neck Cancer with IGRT?

    SciTech Connect (OSTI)

    Li, Z [the 6th People's Hospital of Shanghai Jiaotong University, Shanghai, Shanghai (China); Cleveland Clinic, Cleveland, OH (United States); Shang, Q; Liu, H; Greskovich, J; Koyfman, S; Xia, P [Cleveland Clinic, Cleveland, OH (United States)

    2014-06-01T23:59:59.000Z

    Purpose: Radiation doses delivered to patients with head and neck cancer (HN) may deviate from the planned doses because of variations in patient setup and anatomy. This study was to evaluate whether off-line Adaptive Radiotherapy (ART) is sufficient. Methods: Ten HN patients, who received IMRT under daily imaging guidance using CT-on-rail/KV-CBCT, were randomly selected for this study. For each patient, the daily treatment setup was corrected with translational only directions. Sixty weekly verification CTs were retrospectively analyzed. On these weekly verification CTs, the tumor volumes and OAR contours were manually delineated by a physician. With the treatment iso-center placed on the verification CTs, according to the recorded clinical shifts, the treatment beams from the original IMRT plans were then applied to these CTs to calculate the delivered doses. The electron density of the planning CTs and weekly CTs were overridden to 1 g/cm3. Results: Among 60 fractions, D99 of the CTVs in 4 fractions decreased more than 5% of the planned doses. The maximum dose of the spinal cord exceeded 10% of the planned values in 2 fractions. A close examination indicated that the dose discrepancy in these 6 fractions was due to patient rotations, especially shoulder rotations. After registering these 6 CTs with the planning CT allowing six degree of freedoms, the maximum rotations around 3 axes were > 1.5 for these fractions. With rotation setup errors removed, 4 out of 10 patients still required off-line ART to accommodate anatomical changes. Conclusion: A significant shoulder rotations were observed in 10% fractions, requiring patient re-setup. Off-line ART alone is not sufficient to correct for random variations of patient position, although ART is effective to adapt to patients' gradual anatomic changes. Re-setup or on-line ART may be considered for patients with large deviations detected early by daily IGRT images. The study is supported in part by Siemens Medical Solutions.

  14. Experimentally studied dynamic dose interplay does not meaningfully affect target dose in VMAT SBRT lung treatments

    SciTech Connect (OSTI)

    Stambaugh, Cassandra [Department of Physics, University of South Florida, Tampa, Florida 33612 (United States)] [Department of Physics, University of South Florida, Tampa, Florida 33612 (United States); Nelms, Benjamin E. [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States)] [Canis Lupus LLC, Merrimac, Wisconsin 53561 (United States); Dilling, Thomas; Stevens, Craig; Latifi, Kujtim; Zhang, Geoffrey; Moros, Eduardo; Feygelman, Vladimir [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)] [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida 33612 (United States)

    2013-09-15T23:59:59.000Z

    Purpose: The effects of respiratory motion on the tumor dose can be divided into the gradient and interplay effects. While the interplay effect is likely to average out over a large number of fractions, it may play a role in hypofractionated [stereotactic body radiation therapy (SBRT)] treatments. This subject has been extensively studied for intensity modulated radiation therapy but less so for volumetric modulated arc therapy (VMAT), particularly in application to hypofractionated regimens. Also, no experimental study has provided full four-dimensional (4D) dose reconstruction in this scenario. The authors demonstrate how a recently described motion perturbation method, with full 4D dose reconstruction, is applied to describe the gradient and interplay effects during VMAT lung SBRT treatments.Methods: VMAT dose delivered to a moving target in a patient can be reconstructed by applying perturbations to the treatment planning system-calculated static 3D dose. Ten SBRT patients treated with 6 MV VMAT beams in five fractions were selected. The target motion (motion kernel) was approximated by 3D rigid body translation, with the tumor centroids defined on the ten phases of the 4DCT. The motion was assumed to be periodic, with the period T being an average from the empirical 4DCT respiratory trace. The real observed tumor motion (total displacement ?8 mm) was evaluated first. Then, the motion range was artificially increased to 2 or 3 cm. Finally, T was increased to 60 s. While not realistic, making T comparable to the delivery time elucidates if the interplay effect can be observed. For a single fraction, the authors quantified the interplay effect as the maximum difference in the target dosimetric indices, most importantly the near-minimum dose (D{sub 99%}), between all possible starting phases. For the three- and five-fractions, statistical simulations were performed when substantial interplay was found.Results: For the motion amplitudes and periods obtained from the 4DCT, the interplay effect is negligible (<0.2%). It is also small (0.9% average, 2.2% maximum) when the target excursion increased to 23 cm. Only with large motion and increased period (60 s) was a significant interplay effect observed, with D{sub 99%} ranging from 16% low to 17% high. The interplay effect was statistically significantly lower for the three- and five-fraction statistical simulations. Overall, the gradient effect dominates the clinical situation.Conclusions: A novel method was used to reconstruct the volumetric dose to a moving tumor during lung SBRT VMAT deliveries. With the studied planning and treatment technique for realistic motion periods, regardless of the amplitude, the interplay has nearly no impact on the near-minimum dose. The interplay effect was observed, for study purposes only, with the period comparable to the VMAT delivery time.

  15. Guidance on Dose Rate Measurements for Use in Dose-to-Curie Conversions

    SciTech Connect (OSTI)

    Howell, R.S.

    2000-09-05T23:59:59.000Z

    The dose-to-curie (DTC) methodology used at SRS was developed in early 1994 by Health Physics Technology (HPT) for inclusion in the Site Waste Information Tracking System (WITS). DTC is used to estimate the nuclide activity in a waste container based on the measured dose rate from the container. The DTC method is a simple and easy to apply method that can provide a reasonable estimate of the container activity by nuclide when properly applied. In order to make the method practical, numerous assumptions had to be made and limitations placed on its use. Many of these assumptions and limitations can only be procedurally controlled and must be well understood by these individuals in order to assure proper application numerous the method. These limitations are addressed in this report.

  16. Progress in high-dose radiation dosimetry. Final report

    SciTech Connect (OSTI)

    Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.; Chadwick, K.H.

    1981-01-01T23:59:59.000Z

    The last decade has witnessed a deluge of new high-dose dosimetry techniques and expended applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Requirements for a stable and reliable transfer dose meters have led to further developments of several important high-dose systems: thermoluminescent materials, radiochromic dyes, ceric-cerous solutions analyzed by high-frequency oscillometry. A number of other prospective dosimeters are also treated in this review. In addition, an IAEA program of high-dose intercomparison and standardization for industrial radiation processing is described.

  17. Progress in high-dose radiation dosimetry. Final report

    SciTech Connect (OSTI)

    Ettinger, K.V.; Nam, J.W.; McLaughlin, W.L.; Chadwick, K.H.

    1981-01-01T23:59:59.000Z

    The last decade has witnessed a deluge of new high-dose dosimetry techniques and expended applications of methods developed earlier. Many of the principal systems are calibrated by means of calorimetry, although production of heat is not always the final radiation effect of interest. Requirements for a stable and reliable transfer dose meters have led to further developments of several important high-dose systems: thermoluminescent materials, radiochromic dyes, ceric-cerous solutions analyzed by high-frequency oscillometry. A number of other prospective dosimeters also treated in this review. In addition, an IAEA programme of high-dose intercomparison and standardization for industrial radiation processing is described.

  18. Metabolomic Response of Human Skin Tissue to Low Dose Ionizing...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    for IR exposure at low doses can help provide a scientific basis for establishing radiation protection standards. Little is known regarding the physiological responses to...

  19. Hanford Environmental Dose Reconstruction Project. Monthly report, June 1992

    SciTech Connect (OSTI)

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

    1992-06-01T23:59:59.000Z

    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.

  20. how many doses can you miss before resistance emerges?

    E-Print Network [OSTI]

    Title: Adherence to antiretroviral HIV drugs: how many doses can you miss before resistance emerges? Abstract. The emergence of drug resistance is one of the...

  1. ascending dose study: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Masahiko; Saito, Kimiaki 2015-01-01 72 Environmental Radioactivity 56 (2001) 327340 Radon progeny dose conversion coefficients for Biology and Medicine Websites Summary: Journal of...

  2. adaptive survival responses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    changing environment using sleep. We also quantified 15 Scaling adaptation: climate change response and Geosciences Websites Summary: , and the barriers to adaptation are...

  3. An adaptive mesh refinement technique for dynamics of solids

    E-Print Network [OSTI]

    Trivedi, Abhishek

    2007-01-01T23:59:59.000Z

    adaptations; right: cut-off grid with a solution contour.adaptations; right: cut-off grid with a solution contour.

  4. adaptive signal detection: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    8 INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING Int. J. Adapt. Control Signal Process. (in press) Engineering Websites Summary: predictive control 1....

  5. adaptive signal processing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING Int. J. Adapt. Control Signal Process. (in press) Engineering Websites Summary: predictive control 1....

  6. adaptive information processing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    52 INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING Int. J. Adapt. Control Signal Process. (in press) Engineering Websites Summary: predictive control 1....

  7. adapted damage control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    40 INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING Int. J. Adapt. Control Signal Process. (in press) Engineering Websites Summary: predictive control 1....

  8. adaptive control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    30 INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING Int. J. Adapt. Control Signal Process. (in press) Engineering Websites Summary: predictive control 1....

  9. adaptive predictive control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    applied to analyze the transient Antsaklis, Panos 44 ADAPTIVE ROBUST TRACKING CONTROL OF PRESSURE Engineering Websites Summary: 1---- 1 ADAPTIVE ROBUST TRACKING CONTROL OF...

  10. active adaptive management: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    begun to embrace the concept adaptive management as an alternative to traditional natural resource planning and management models. Adaptive management may provide BLM managers ......

  11. adaptive management department: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    begun to embrace the concept adaptive management as an alternative to traditional natural resource planning and management models. Adaptive management may provide BLM managers ......

  12. National Adaptation Forum Webinar Series: Out of Town, Not Out...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Adaptation Forum Webinar Series: Out of Town, Not Out of Trouble: Small Agriculture and Indigenous Communities National Adaptation Forum Webinar Series: Out of Town, Not Out of...

  13. Farming in a Changing Climate: Agricultural Adaptation in Canada

    E-Print Network [OSTI]

    Jain, Varinder

    2010-01-01T23:59:59.000Z

    Agricultural Adaptation in Canada Ellen Wall, Barry Smit,Agricultural Adaptation in Canada. Vancouver, BC: Universitythe agri-food sector in Canada, the insights provided are so

  14. Enabling High Efficiency Low Temperature Combustion by Adaptive...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low Temperature Combustion by Adaptive In-Situ Jet Cooling Enabling High Efficiency Low Temperature Combustion by Adaptive In-Situ Jet Cooling A new approach, called...

  15. adaptive interactive technologies: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Shock-induced combustion Fluid-structure interaction Implementation Parallel Adaptive Cartesian Upwind Mathematics Websites Summary: Finite volume methods Adaptive mesh refinement...

  16. adaptive responses genomic: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 Biochemical Adaptation 169 From: Integrative Physiology in the Proteomics and Post-Genomics Age Biology and Medicine Websites Summary: Biochemical Adaptation 169 169 From:...

  17. adaptive optimal control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    result. In this procedure it is essential Campi, Marco 3 Adaptive Control System Optimization for Vibration Control of Flexible Structures Engineering Websites Summary: Adaptive...

  18. adaptive particle swarm: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Last Page Topic Index 1 An Adaptive Learning Particle Swarm Optimizer for Function Optimization Computer Technologies and Information Sciences Websites Summary: An Adaptive...

  19. adaptive intrusion detection: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Last Page Topic Index 1 Adaptive Model Generation for Intrusion Detection Systems Computer Technologies and Information Sciences Websites Summary: Adaptive Model Generation for...

  20. Seismic Technology Adapted to Analyzing and Developing Geothermal...

    Broader source: Energy.gov (indexed) [DOE]

    Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Seismic Technology Adapted to Analyzing and Developing...

  1. Radiation Therapy Photon Beams Dose Conformation According to Dose Distribution Around Intracavitary-Applied Brachytherapy Sources

    SciTech Connect (OSTI)

    Jurkovic, Slaven [Department of Radiotherapy and Oncology, University Hospital, Rijeka (Croatia)], E-mail: slaven.jurkovic@ri.htnet.hr; Zauhar, Gordana [Department of Physics, School of Medicine, Rijeka (Croatia); Faj, Dario [Department of Radiotherapy and Oncology, University Hospital, Osijek (Croatia); Radojcic, Deni Smilovic; Svabic, Manda [Department of Radiotherapy and Oncology, University Hospital, Rijeka (Croatia)

    2010-04-01T23:59:59.000Z

    Intracavitary application of brachytherapy sources followed by external beam radiation is essential for the local treatment of carcinoma of the cervix. Due to very high doses to the central portion of the target volume delivered by brachytherapy sources, this part of the target volume must be shielded while being irradiated by photon beams. Several shielding techniques are available, from rectangular block and standard cervix wedge to more precise, customized step wedge filters. Because the calculation of a step wedge filter's shape was usually based on effective attenuation coefficient, an approach that accounts, in a more precise way, for the scattered radiation, is suggested. The method was verified under simulated clinical conditions using film dosimetry. Measured data for various compensators were compared to the numerically determined sum of the dose distribution around brachytherapy sources and one of compensated beam. Improvements in total dose distribution are demonstrated, using our method. Agreement between calculation and measurements were within 3%. Sensitivity of the method on sources displacement during treatment has also been investigated.

  2. Ground-water contribution to dose from past Hanford Operations. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Freshley, M.D.; Thorne, P.D.

    1992-08-01T23:59:59.000Z

    The Hanford Environmental Dose Reconstruction (HEDR) Project is being conducted to estimate radiation doses that populations and individuals could have received from Hanford Site operations from 1944 to the present. Four possible pathways by which radionuclides migrating in ground water on the Hanford Site could have reached the public have been identified: (1) through contaminated ground water migrating to the Columbia River; (2) through wells on or adjacent to the Hanford Site; (3) through wells next to the Columbia River downstream of Hanford that draw some or all of their water from the river (riparian wells); and (4) through atmospheric deposition resulting in contamination of a small watershed that, in turn, results in contamination of a shallow well or spring by transport in the ground water. These four pathways make up the ``ground-water pathway,`` which is the subject of this study. Assessment of the ground-water pathway was performed by (1) reviewing the existing extensive literature on ground water and ground-water monitoring at Hanford and (2) performing calculations to estimate radionuclide concentrations where no monitoring data were collected. Radiation doses that would result from exposure to these radionuclides were calculated.

  3. Implementing Adaptive Performance Management in Server Applications

    SciTech Connect (OSTI)

    Liu, Yan; Gorton, Ian

    2007-06-11T23:59:59.000Z

    Performance and scalability are critical quality attributes for server applications in Internet-facing business systems. These applications operate in dynamic environments with rapidly fluctuating user loads and resource levels, and unpredictable system faults. Adaptive (autonomic) systems research aims to augment such server applications with intelligent control logic that can detect and react to sudden environmental changes. However, developing this adaptive logic is complex in itself. In addition, executing the adaptive logic consumes processing resources, and hence may (paradoxically) adversely affect application performance. In this paper we describe an approach for developing high-performance adaptive server applications and the supporting technology. The Adaptive Server Framework (ASF) is built on standard middleware services, and can be used to augment legacy systems with adaptive behavior without needing to change the application business logic. Crucially, ASF provides built-in control loop components to optimize the overall application performance, which comprises both the business and adaptive logic. The control loop is based on performance models and allows systems designers to tune the performance levels simply by modifying high level declarative policies. We demonstrate the use of ASF in a case study.

  4. Determination of radionuclides and pathways contributing to dose in 1945. Hanford Environmental Dose Reconstruction Project: Dose code recovery activities, Calculation 003

    SciTech Connect (OSTI)

    Napier, B.A.

    1992-12-01T23:59:59.000Z

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 003) examined the contributions of numerous radionuclides to dose via environmental exposures and accumulation in foods. This study builds on the work initiated in the first scoping study of iodine in cow`s milk (calculation 001). Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows` milk from Feeding Regime 1, as described in Calculation 001.

  5. Dose assessments in relation to disposal at sea under the

    E-Print Network [OSTI]

    of radioactivity, and dredging activity, in coastal waters of the UK 2.1 Radioactivity in the environment 2 Standards 2.5 Dredging activity in the UK 2.6 Other licensed activity 3 Dose Assessment procedures 3, to derive assessment for dredging at Whitehaven in 2004. Table 8 Comparison of gamma dose rates (

  6. Hanford Site Annual Report Radiological Dose Calculation Upgrade Evaluation

    SciTech Connect (OSTI)

    Snyder, Sandra F.

    2010-02-28T23:59:59.000Z

    Operations at the Hanford Site, Richland, Washington, result in the release of radioactive materials to offsite residents. Site authorities are required to estimate the dose to the maximally exposed offsite resident. Due to the very low levels of exposure at the residence, computer models, rather than environmental samples, are used to estimate exposure, intake, and dose. A DOS-based model has been used in the past (GENII version 1.485). GENII v1.485 has been updated to a Windows-based software (GENII version 2.08). Use of the updated software will facilitate future dose evaluations, but must be demonstrated to provide results comparable to those of GENII v1.485. This report describes the GENII v1.485 and GENII v2.08 dose exposure, intake, and dose estimates for the maximally exposed offsite resident reported for calendar year 2008. The GENII v2.08 results reflect updates to implemented algorithms. No two environmental models produce the same results, as was again demonstrated in this report. The aggregated dose results from 2008 Hanford Site airborne and surface water exposure scenarios provide comparable dose results. Therefore, the GENII v2.08 software is recommended for future offsite resident dose evaluations.

  7. Total dose radiation response of plasma-damaged NMOS devices

    SciTech Connect (OSTI)

    Yue, J.; Lo, E.; Flanery, M. [Honeywell Solid-State Electronic Center, Plymouth, MN (United States)] [Honeywell Solid-State Electronic Center, Plymouth, MN (United States)

    1997-11-01T23:59:59.000Z

    Plasma-damaged NMOS devices were subjected to the X-ray total dose irradiation. Unlike the traditional hot-carrier or Fowler-Nordheim (F-N) stress where the hole trap generation is less pronounced, this study shows enhanced hole trap and interface trap generation on plasma-damaged devices after total dose irradiation.

  8. Measurements of Cavitation Dose, Echogenicity, and Temperature during Ultrasound Ablation

    E-Print Network [OSTI]

    Mast, T. Douglas

    Measurements of Cavitation Dose, Echogenicity, and Temperature during Ultrasound Ablation T traces from the array, time-domain signals received by a 1 MHz, unfocused passive cavitation detector signals received by the array. Cavitation dose was quantified from the spectra of signals measured

  9. Adaptive control for optimizing microalgae production

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Adaptive control for optimizing microalgae production Francis Mairet Rafael Mu for light-limited microalgae culture. This controller regulates the light absorption factor, defined productivity under day-night cycles. Keywords: Nonlinear controller, Microalgae, Optimization, Biomass

  10. Exponential convergence with adaptive Monte Carlo

    SciTech Connect (OSTI)

    Booth, T.E.

    1997-11-01T23:59:59.000Z

    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.

  11. Multi-model adaptive spatial hypertext

    E-Print Network [OSTI]

    Francisco-Revilla, Luis

    2005-02-17T23:59:59.000Z

    in response to multiple relevant factors. The framework is composed of four parts: a general system architecture, a definition of the fundamental concepts in spatial hypermedia, an ontological classification of the adaptation strategies, and the philosophy...

  12. Adaptive Importance Sampling via Stochastic Convex Programming

    E-Print Network [OSTI]

    Adaptive Importance Sampling via Stochastic Convex Programming Ernest K. Ryu1 and Stephen P. Boyd1 Abstract We show that the variance of the Monte Carlo estimator that is importance sam- pled from

  13. Scalable Adaptive Multilevel Solvers for Multiphysics Problems

    SciTech Connect (OSTI)

    Xu, Jinchao

    2014-12-01T23:59:59.000Z

    In this project, we investigated adaptive, parallel, and multilevel methods for numerical modeling of various real-world applications, including Magnetohydrodynamics (MHD), complex fluids, Electromagnetism, Navier-Stokes equations, and reservoir simulation. First, we have designed improved mathematical models and numerical discretizaitons for viscoelastic fluids and MHD. Second, we have derived new a posteriori error estimators and extended the applicability of adaptivity to various problems. Third, we have developed multilevel solvers for solving scalar partial differential equations (PDEs) as well as coupled systems of PDEs, especially on unstructured grids. Moreover, we have integrated the study between adaptive method and multilevel methods, and made significant efforts and advances in adaptive multilevel methods of the multi-physics problems.

  14. Adaptive Reliability Analysis of Excavation Problems

    E-Print Network [OSTI]

    Park, Jun Kyung

    2012-10-19T23:59:59.000Z

    . This analysis couples the adaptive design capabilities of the observational method with updated reliability indices, to be used in risk-based design decisions. A probabilistic framework is developed to predict three-dimensional deformation profiles due...

  15. Robust adaptive control of switched systems

    E-Print Network [OSTI]

    El-Rifai, Khalid, 1979-

    2007-01-01T23:59:59.000Z

    In this thesis, robust adaptive controllers are developed for classes of switched nonlinear systems. Switched systems are those governed by differential equations, which undergo vector field switching due to sudden changes ...

  16. Skeletal adaptation to reduced mechanical loading

    E-Print Network [OSTI]

    Eliman, Rachel

    2014-01-01T23:59:59.000Z

    Bone adapts its mass and architecture in response to its mechanical environment. Yet control of this process by mechanical cues is poorly understood, particularly for unloading. Defining the fundamental mechanoregulation ...

  17. Adaptive optic demonstrators for extremely large telescopes

    E-Print Network [OSTI]

    Campbell, Michael Aloysius

    2011-06-27T23:59:59.000Z

    The next generation of ground-based optical/infrared (IR) telescopes will have primary mirrors of up to 42 m. To take advantage of the large potential increase in angular resolution, adaptive optics will be essential to ...

  18. Adaptive sampling in autonomous marine sensor networks

    E-Print Network [OSTI]

    Eickstedt, Donald Patrick

    2006-01-01T23:59:59.000Z

    In this thesis, an innovative architecture for real-time adaptive and cooperative control of autonomous sensor platforms in a marine sensor network is described in the context of the autonomous oceanographic network scenario. ...

  19. Fast Adaptive Silhouette Area based Template Matching

    E-Print Network [OSTI]

    Zachmann, Gabriel

    Fast Adaptive Silhouette Area based Template Matching Daniel Mohr and Gabriel Zachmann If (Technical Informatics and Computer Systems) Prof. Dr. Gabriel Zachmann (Computer Graphics) Prof. Dr Template Matching Daniel Mohr and Gabriel Zachmann Clausthal University of Technology, Department

  20. A Logical Characterization of Adaptive Educational Hypermedia

    E-Print Network [OSTI]

    Henze, Nicola

    reference models for adaptive hypermedia, e.g. the AHAM Reference Model [4], or the Munich Reference Model [20]. Both, the AHAM and Munich Reference Model, extend the Dexter Hypertext Model [16], and pro- vide

  1. Convert! : the adaptive reuse of churches

    E-Print Network [OSTI]

    Kiley, Christopher John, 1972-

    2004-01-01T23:59:59.000Z

    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 ...

  2. Challenges of Adapting to a Changing Climate

    E-Print Network [OSTI]

    Hurd, Brian H.

    2008-01-01T23:59:59.000Z

    of Global Climate Change on Agriculture: An Interpretiveon U.S. Agriculture, in THE IMPACT OF CLIMATE CHANGE ON THEclimate change and the potential roles for adaptation are more severe for ecosystems than they are for managed systems like agriculture.

  3. Anisotropic Grid Adaptation for Multiple Aerodynamic Outputs

    E-Print Network [OSTI]

    Venditti, David A.

    Anisotropic gridadaptive strategies are presented for viscous flow simulations in which the accurate prediction of multiple aerodynamic outputs (such as the lift, drag, and moment coefficients) is required from a single ...

  4. Developmental Plasticity Links Local Adaptation and Evolutionary

    E-Print Network [OSTI]

    Badyaev, Alex

    Developmental Plasticity Links Local Adaptation and Evolutionary Diversification in Foraging, University of Arizona, Tucson, Arizona Developmental plasticity is thought to reconcile the constraining role morphology into adulthood, providing an opportunity to directly examine the links between plasticity of bone

  5. Determination of radionuclides and pathways contributing to cumulative dose

    SciTech Connect (OSTI)

    Napier, B.A.

    1992-12-01T23:59:59.000Z

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 004) examined the contributions of numerous radionuclides to cumulative dose via environmental exposures and accumulation in foods. Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows' milk from Feeding Regime 1, as described in calculation 002. This calculation specifically addresses cumulative radiation doses to infants and adults resulting from releases occurring over the period 1945 through 1972.

  6. Topographic Effects on Ambient Dose Equivalent Rates from Radiocesium Fallout

    E-Print Network [OSTI]

    Malins, Alex; Machida, Masahiko; Saito, Kimiaki

    2015-01-01T23:59:59.000Z

    Land topography can affect air radiation dose rates by locating radiation sources closer to, or further, from detector locations when compared to perfectly flat terrain. Hills and slopes can also shield against the propagation of gamma rays. To understand the possible magnitude of topographic effects on air dose rates, this study presents calculations for ambient dose equivalent rates at a range of heights above the ground for varying land topographies. The geometries considered were angled ground at the intersection of two planar surfaces, which is a model for slopes neighboring flat land, and a simple conical geometry, representing settings from hilltops to valley bottoms. In each case the radiation source was radioactive cesium fallout, and the slope angle was varied systematically to determine the effect of topography on the air dose rate. Under the assumption of homogeneous fallout across the land surface, and for these geometries and detector locations, the dose rates at high altitudes are more strongly...

  7. Adaptive gain improves reactor control

    SciTech Connect (OSTI)

    Whatley, M.J.; Pott, D.C.

    1984-05-01T23:59:59.000Z

    An interesting application of the modern control theory technique called adaptive control is presently in use on a process located at a plant in the Standard Oil Co. (Ind.) system. The results of this application are: first, the transformation of an uncontrollable process to a controllable one; and, second, a significant economic savings to the corporation. It also shows that a detailed analysis of the mechanical, chemical and control systems can provide both the basis for revising an existing control system and some of the reasons why that system is inadequate. The contrast between classical and modern control theories is seen in four major areas. In classical systems, the controller manipulates the error to calculate its output. The error is subjected to a limited number of analog computing functions such as multiplication by a constant and integration. Each controller has one specific strategy--to hold the measured variable at the setpoint. And each controller controls only one variable, independent of all others. In a modern system, the controller can manipulate many different variables in addition to the error to compute its output. Its computing power is unlimited in a practical sense. It can do all classical computations plus many others, including a table look-up. The controller can independently change its strategy as a function of time or the condition of the process. It can also control many variables at one time to accomplish a complex objective. The implementation of a modern control theory project requires a good understanding of the dynamic, as well as the steady-state character of the process. As you can see we are limited only by our understanding of the process, our imagination, and the economics of the situation.

  8. The Durham ELT adaptive optics simulation platform

    E-Print Network [OSTI]

    Alastair Basden; Timothy Butterley; Richard Myers; Richard Wilson

    2006-11-09T23:59:59.000Z

    Adaptive optics systems are essential on all large telescopes where image quality is important. These are complex systems with many design parameters requiring optimisation before good performance can be achieved. The simulation of adaptive optics systems is therefore necessary to categorise the expected performance. This paper describes an adaptive optics simulation platform, developed at Durham University, which can be used to simulate adaptive optics systems on the largest proposed future extremely large telescopes (ELTs) as well as current systems. This platform is modular, object oriented and has the benefit of hardware application acceleration which can be used to improve the simulation performance, essential for ensuring that the run time of a given simulation is acceptable. The simulation platform described here can be highly parallelised using parallelisation techniques suited for adaptive optics simulation, whilst still offering the user complete control while the simulation is running. Results from the simulation of a ground layer adaptive optics system are provided as an example to demonstrate the flexibility of this simulation platform.

  9. Phase 1 of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Not Available

    1991-08-01T23:59:59.000Z

    The work described in this report was prompted by the public's concern about potential effect from the radioactive materials released from the Hanford Site. The Hanford Environmental Dose Reconstruction (HEDR) Project was established to estimate radiation dose the public might have received from the Hanford Site since 1944, when facilities began operating. Phase 1 of the HEDR Project is a pilot'' or demonstration'' phase. The objectives of this initial phase were to determine whether enough historical information could be found or reconstructed to be used for dose estimation and develop and test conceptual and computational models for calculating credible dose estimates. Preliminary estimates of radiation doses were produced in Phase 1 because they are needed to achieve these objectives. The reader is cautioned that the dose estimates provided in this and other Phase 1 HEDR reports are preliminary. As the HEDR Project continues, the dose estimates will change for at least three reasons: more complete input information for models will be developed; the models themselves will be refined; and the size and shape of the geographic study area will change. This is one of three draft reports that summarize the first phase of the four-phased HEDR Project. This, the Summary Report, is directed to readers who want a general understanding of the Phase 1 work and preliminary dose estimates. The two other reports -- the Air Pathway Report and the Columbia River Pathway Report -- are for readers who understand the radiation dose assessment process and want to see more technical detail. Detailed descriptions of the dose reconstruction process are available in more than 20 supporting reports listed in Appendix A. 32 refs., 46 figs.

  10. Enrofloxacin and amikacin pharmacokinetics in Scimitar-horned oryx (Oryx dammah) following a single intravenous dose

    E-Print Network [OSTI]

    Gamble, Kathryn Christine

    1995-01-01T23:59:59.000Z

    metabolic standard, metabolic energy cost (NEC), is used to calculate a dose. MEC, ?. ?. = K(Weight' ") MEC. . ?, = K (Weight'-") Dose?. . . , = Total daily drug dose (mg) MECaoee = Dose?. . . , /NEC . . . , Dose. ?. ?. = MEC. ???X NEC, . . . (mg... and clinically used in the model. " Once a dose is established, NES can be further employed to suggest dose interval in a regimen. Calculation of MEC by weight basis is the specific minimum energy cost (SMEC) of both the model and the exotic. SMEC...

  11. IEEE INFOCOM 2001 1 Pricing Network Resources for Adaptive

    E-Print Network [OSTI]

    Wang, Xin

    , and provides a natural and equitable incentive for applications to adapt their service contract according

  12. Model Reference Adaptive Control Framework for Real Time Traffic

    E-Print Network [OSTI]

    Minnesota, University of

    Adaptive Control #12;12 Prescriptive Dynamic Traffic Assignment A Prediction Model and the Reference ModelModel Reference Adaptive Control Framework for Real Time Traffic Management Under Emergency Movement Volume Adaptive Controller Model Reference Adaptive Control (MRAC) Assumptions Super Zone Concept

  13. DCS1800/WCDMA ADAPTIVE VOLTAGE-CONTROLLED OSCILLATOR

    E-Print Network [OSTI]

    Serdijn, Wouter A.

    DCS1800/WCDMA ADAPTIVE VOLTAGE-CONTROLLED OSCILLATOR Aleksandar Tasi, Wouter A. Serdijn and John R, an adaptive 2G/3G voltage-controlled oscillator (VCO) is described in this paper. For the DCS1800 operation with this reasoning, an adaptive 2G/3G voltage- controlled oscillator, meant for a dual-standard adaptive front

  14. Adaptive Plasticity and Plasticity as an Adaptation: A Selective Review of Plasticity in Animal Morphology and Life History

    E-Print Network [OSTI]

    Gotthard, Karl

    Adaptive Plasticity and Plasticity as an Adaptation: A Selective Review of Plasticity in Animal wide-ranging. All key REVIEW references should be cited. A summary is required. Adaptive plasticity and plasticity as an adaptation: a selective review of plasticity in animal morphology and life history Karl

  15. Adaptive method with intercessory feedback control for an intelligent agent

    DOE Patents [OSTI]

    Goldsmith, Steven Y.

    2004-06-22T23:59:59.000Z

    An adaptive architecture method with feedback control for an intelligent agent provides for adaptively integrating reflexive and deliberative responses to a stimulus according to a goal. An adaptive architecture method with feedback control for multiple intelligent agents provides for coordinating and adaptively integrating reflexive and deliberative responses to a stimulus according to a goal. Re-programming of the adaptive architecture is through a nexus which coordinates reflexive and deliberator components.

  16. EcoAdapt Working Paper Series N1 Adaptation to climate change for local development

    E-Print Network [OSTI]

    Boyer, Edmond

    1 EcoAdapt Working Paper Series N°1 Adaptation to climate change for local development Análisis in terms of employment, water situation and land use, at a quantitative and qualitative level, in three and summer pastures, due to the geographic and climatic conditions. hal-01059368,version1-30Aug2014 #12

  17. A Rate-Adaptive Multimedia Multicasting Mechanism. . . 23 A Rate-Adaptive Multimedia Multicasting Mechanism in

    E-Print Network [OSTI]

    A Rate-Adaptive Multimedia Multicasting Mechanism. . . 23 A Rate-Adaptive Multimedia Multicasting and Multimedia Department ENST Bretagne, 2, rue de la Chataigneraie - CS 17607 35576 Cesson Sevigne Cedex rapidly. One of the major driving factors of WLANs is multimedia services such as VOD or HDTV delivered

  18. Adaptive and Non-Adaptive Distribution Functions for DSA Melanie Smith

    E-Print Network [OSTI]

    Mailler, Roger

    Adaptive and Non-Adaptive Distribution Functions for DSA Melanie Smith University of Tulsa 800 S. Tucker Drive Tulsa, OK 74104 melanie@utulsa.edu Sandip Sen University of Tulsa 800 S. Tucker Drive Tulsa, OK 74104 sandip-sen@utulsa.edu Roger Mailler University of Tulsa 800 S. Tucker Drive Tulsa, OK 74104

  19. Adapting to WisconsinAdapting to Wisconsin''ss Changing WatersChanging Waters

    E-Print Network [OSTI]

    Sheridan, Jennifer

    spells and droughts in some places, to colder cold spells and more violent storms, more intense flooding://wicci.wisc.edu #12;WICCI Identifying impacts and adaptation strategies Evaluate potential effects on industry, agriculture, tourism, and other human activities. Develop and recommend adaptation strategies. Mission: Assess

  20. Overview of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Shipler, D.B.; Napier, B.A.; Ikenberry, T.A.

    1992-04-01T23:59:59.000Z

    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that specific and representative individuals and populations may have received as a result of releases of radioactive materials from historical operations at the Hanford Site. These dose estimates would account for the uncertainties of information regarding facilities operations, environmental monitoring, demography, food consumption and lifestyles, and the variability of natural phenomena. Other objectives of the HEDR Project include: supporting the Hanford Thyroid Disease Study (HTDS), declassifying Hanford-generated information and making it available to the public, performing high-quality, credible science, and conducting the project in an open, public forum. The project is briefly described.

  1. Peak Dose Assessment for Proposed DOE-PPPO Authorized Limits

    SciTech Connect (OSTI)

    Maldonado, Delis [Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States). Independent Environmental Assessment and Verification Program

    2012-06-01T23:59:59.000Z

    The Oak Ridge Institute for Science and Education (ORISE), a U.S. Department of Energy (DOE) prime contractor, was contracted by the DOE Portsmouth/Paducah Project Office (DOE-PPPO) to conduct a peak dose assessment in support of the Authorized Limits Request for Solid Waste Disposal at Landfill C-746-U at the Paducah Gaseous Diffusion Plant (DOE-PPPO 2011a). The peak doses were calculated based on the DOE-PPPO Proposed Single Radionuclides Soil Guidelines and the DOE-PPPO Proposed Authorized Limits (AL) Volumetric Concentrations available in DOE-PPPO 2011a. This work is provided as an appendix to the Dose Modeling Evaluations and Technical Support Document for the Authorized Limits Request for the C-746-U Landfill at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky (ORISE 2012). The receptors evaluated in ORISE 2012 were selected by the DOE-PPPO for the additional peak dose evaluations. These receptors included a Landfill Worker, Trespasser, Resident Farmer (onsite), Resident Gardener, Recreational User, Outdoor Worker and an Offsite Resident Farmer. The RESRAD (Version 6.5) and RESRAD-OFFSITE (Version 2.5) computer codes were used for the peak dose assessments. Deterministic peak dose assessments were performed for all the receptors and a probabilistic dose assessment was performed only for the Offsite Resident Farmer at the request of the DOE-PPPO. In a deterministic analysis, a single input value results in a single output value. In other words, a deterministic analysis uses single parameter values for every variable in the code. By contrast, a probabilistic approach assigns parameter ranges to certain variables, and the code randomly selects the values for each variable from the parameter range each time it calculates the dose (NRC 2006). The receptor scenarios, computer codes and parameter input files were previously used in ORISE 2012. A few modifications were made to the parameter input files as appropriate for this effort. Some of these changes included increasing the time horizon beyond 1,050 years (yr), and using the radionuclide concentrations provided by the DOE-PPPO as inputs into the codes. The deterministic peak doses were evaluated within time horizons of 70 yr (for the Landfill Worker and Trespasser), 1,050 yr, 10,000 yr and 100,000 yr (for the Resident Farmer [onsite], Resident Gardener, Recreational User, Outdoor Worker and Offsite Resident Farmer) at the request of the DOE-PPPO. The time horizons of 10,000 yr and 100,000 yr were used at the request of the DOE-PPPO for informational purposes only. The probabilistic peak of the mean dose assessment was performed for the Offsite Resident Farmer using Technetium-99 (Tc-99) and a time horizon of 1,050 yr. The results of the deterministic analyses indicate that among all receptors and time horizons evaluated, the highest projected dose, 2,700 mrem/yr, occurred for the Resident Farmer (onsite) at 12,773 yr. The exposure pathways contributing to the peak dose are ingestion of plants, external gamma, and ingestion of milk, meat and soil. However, this receptor is considered an implausible receptor. The only receptors considered plausible are the Landfill Worker, Recreational User, Outdoor Worker and the Offsite Resident Farmer. The maximum projected dose among the plausible receptors is 220 mrem/yr for the Outdoor Worker and it occurs at 19,045 yr. The exposure pathways contributing to the dose for this receptor are external gamma and soil ingestion. The results of the probabilistic peak of the mean dose analysis for the Offsite Resident Farmer indicate that the average (arithmetic mean) of the peak of the mean doses for this receptor is 0.98 mrem/yr and it occurs at 1,050 yr. This dose corresponds to Tc-99 within the time horizon of 1,050 yr.

  2. Three-dimensional anisotropic adaptive filtering of projection data for noise reduction in cone beam CT

    SciTech Connect (OSTI)

    Maier, Andreas; Wigstroem, Lars; Hofmann, Hannes G.; Hornegger, Joachim; Zhu Lei; Strobel, Norbert; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Stanford University, Stanford, California 94305 (United States) and Center for Medical Image Science and Visualization, Linkoeping University, Linkoeping (Sweden); Pattern Recognition Laboratory, Department of Computer Science, Friedrich-Alexander University of Erlangen-Nuremberg, 91054, Erlangen (Germany); Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Siemens AG Healthcare, Forchheim 91301 (Germany); Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2011-11-15T23:59:59.000Z

    Purpose: The combination of quickly rotating C-arm gantry with digital flat panel has enabled the acquisition of three-dimensional data (3D) in the interventional suite. However, image quality is still somewhat limited since the hardware has not been optimized for CT imaging. Adaptive anisotropic filtering has the ability to improve image quality by reducing the noise level and therewith the radiation dose without introducing noticeable blurring. By applying the filtering prior to 3D reconstruction, noise-induced streak artifacts are reduced as compared to processing in the image domain. Methods: 3D anisotropic adaptive filtering was used to process an ensemble of 2D x-ray views acquired along a circular trajectory around an object. After arranging the input data into a 3D space (2D projections + angle), the orientation of structures was estimated using a set of differently oriented filters. The resulting tensor representation of local orientation was utilized to control the anisotropic filtering. Low-pass filtering is applied only along structures to maintain high spatial frequency components perpendicular to these. The evaluation of the proposed algorithm includes numerical simulations, phantom experiments, and in-vivo data which were acquired using an AXIOM Artis dTA C-arm system (Siemens AG, Healthcare Sector, Forchheim, Germany). Spatial resolution and noise levels were compared with and without adaptive filtering. A human observer study was carried out to evaluate low-contrast detectability. Results: The adaptive anisotropic filtering algorithm was found to significantly improve low-contrast detectability by reducing the noise level by half (reduction of the standard deviation in certain areas from 74 to 30 HU). Virtually no degradation of high contrast spatial resolution was observed in the modulation transfer function (MTF) analysis. Although the algorithm is computationally intensive, hardware acceleration using Nvidia's CUDA Interface provided an 8.9-fold speed-up of the processing (from 1336 to 150 s). Conclusions: Adaptive anisotropic filtering has the potential to substantially improve image quality and/or reduce the radiation dose required for obtaining 3D image data using cone beam CT.

  3. CY 1995 radiation dose reconciliation report and resulting CY 1996 dose estimate for the 324 nuclear facility

    SciTech Connect (OSTI)

    Landsman, S.D.; Thornhill, R.E.; Peterson, C.A.

    1996-04-01T23:59:59.000Z

    In this report, the dose estimate for CY 1995 is reconciled by month wih actual doses received. Results of the reconciliation were used to revise estimates of worker dose for CY 1996. Resulting dose estimate for the facility is also included. Support for two major programs (B-Cell Cleanout and Surveillance and Maintenance) accounts for most of the exposure received by workers in the faility. Most of the expousre received by workers comes from work in the Radiochemical Engineering Complex airlock. In spite of schedule and work scope changes during CY 1995, dose estimates were close to actual exposures received. A number of ALARA measures were taken throughout the year; exposure reduction due to those was 20.6 Man-Rem, a 28% reduction from the CY 1995 estimate. Baseline estimates for various tasks in the facility were used to compile the CY 1996 dose estimate of 45.4 Man-Rem; facility goal for CY 1996 is to reduce worker dose by 20%, to 36.3 Man-Rem.

  4. Electronic dose conversion technique using a NaI(Tl) detector for assessment of exposure dose rate from environmental radiation

    SciTech Connect (OSTI)

    Cho, G.; Kim, H.K. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of)] [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of); Woo, H.; Oh, G. [Korea Electric Power Research Inst., Taejon (Korea, Republic of)] [Korea Electric Power Research Inst., Taejon (Korea, Republic of); Ha, D.K. [Samchang Enterprise Co., Anyang (Korea, Republic of)] [Samchang Enterprise Co., Anyang (Korea, Republic of)

    1998-06-01T23:59:59.000Z

    An electronic dose conversion technique to assess the exposure dose rate due to environmental radiation especially from terrestrial sources was developed. For a 2 x 2 inch cylindrical NaI(Tl) scintillation detector, pulse-height spectra were obtained for gamma-rays of energy up to 3 MeV by Monte Carlo simulation. Based on the simulation results and the experimentally fitted energy resolution, dose conversion factors were calculated by a numerical decomposition method. These calculated dose conversion factors were, then, electronically implemented to a developed dose conversion unit (DCU) which is a microprocessor-controlled single channel analyzer (SCA) with variable discrimination levels. The simulated spectra were confirmed by measurement of several monoenergetic gamma spectra with a multichannel analyzer (MCA). The converted exposure dose rates from the implemented dose conversion algorithm in the DCU were also evaluated for a field test in the vicinity of the nuclear power plant at Kori as well as for several standard sources, and the results were in good agreement with separate measurement by a high pressure ionization chamber (HPIC) within a 6.4% deviation.

  5. Genetic Factors Affecting Susceptibility to Low Dose & Low Dose-Rate Radiation

    SciTech Connect (OSTI)

    Bedford, Joel

    2014-04-18T23:59:59.000Z

    Our laboratory has, among other things, developed and used the gamma H2AX focus assay and other chromosomal and cell killing assays to show that differences in this DNA double strand break (dsb) related response can be clearly and distinctly demonstrated for cells which are mildly hyper-radiosensitive such as those associated with A-T heterozygosity. We have found this level of mild hypersensitivity for cells from some 20 to 30 % of apparently normal individuals and from apparently normal parents of Retinoblastoma patients. We found significant differences in gene expression in somatic cells from unaffected parents of Rb patients as compared with normal controls, suggesting that these parents may harbor some as yet unidentified genetic abnormality. In other experiments we sought to determine the extent of differences in normal human cellular reaponses to radiation depending on their irradiation in 2D monolayer vs 3D organized acinar growth conditions. We exmined cell reproductive death, chromosomal aberration induction, and the levels of ?-H2AX foci in cells after single acute gamma-ray doses and immediately after 20 hours of irradiation at a dose rate of 0.0017 Gy/min. We found no significant differences in the dose-responses of these cells under the 2D or 3D growth conditions. While this does not mean such differences cannot occur in other situations, it does mean that they do not generally or necessarily occur. In another series of studies in collaboration with Dr Chuan Li, with supprt from this current grant. We reported a role for apoptotic cell death in promoting wound healing and tissue regeneration in mice. Apoptotic cells released growth signals that stimulated the proliferation of progenitor or stem cells. In yet another collaboration with Dr, B. Chen with funds from this grant, the relative radiosensitivity to cell killing as well as chromosomal instability of 13 DNA-PKcs site-directed mutant cell lines (defective at phosphorylation sites or kinase activity) were examined after exposure of synchronized G1 cells to 137Cs c rays. DNA-PKcs mutant cells defective in phosphorylation at multiple sites withinthe T2609 cluster or within the PI3K domain displayed extreme radiosensitivity. Cells defective at the S2056 cluster or T2609 single site alone were only mildly radiosensitive, but cells defective at even one site in both the S2056 and T2609 clusters were maximally radiosensitive. Thus a synergism between the capacity for phosphorylation at the S2056 and T2609 clusterswas found to be critical for induction of radiosensitivity.

  6. annual dose mass: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  7. additional thyroid dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  8. accelerators rooms doses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  9. anticipated radiological dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  10. assessing radiation dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  11. accumulated radiation dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  12. acetaminophen correct dosing: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  13. assessing total doses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  14. annual effective dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  15. approximate organ doses: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  16. antigen dose dependent: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  17. annual radiation dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  18. average glandular dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  19. adjust total dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  20. assessing skin dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  1. antagonist multiple dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  2. analytic imrt dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk and 4,600 at the plutonium sep- aration plant. If we allow for an average work...

  3. Determination of radionuclides and pathways contributing to dose in 1945

    SciTech Connect (OSTI)

    Napier, B.A.

    1992-12-01T23:59:59.000Z

    A series of scoping calculations has been undertaken to evaluate the absolute and relative contributions of different radionuclides and exposure pathways to doses that may have been received by individuals living in the vicinity of the Hanford Site. This scoping calculation (Calculation 003) examined the contributions of numerous radionuclides to dose via environmental exposures and accumulation in foods. This study builds on the work initiated in the first scoping study of iodine in cow's milk (calculation 001). Addressed in this calculation were the contributions to organ and effective dose of infants and adults from (1) air submersion and groundshine external dose, (2) inhalation, (3) ingestion of soil by humans, (4) ingestion of leafy vegetables, (5) ingestion of other vegetables and fruits, (6) ingestion of meat, (7) ingestion of eggs, and (8) ingestion of cows' milk from Feeding Regime 1, as described in Calculation 001.

  4. An external dose reconstruction involving a radiological dispersal device

    E-Print Network [OSTI]

    Hearnsberger, David Wayne

    2007-04-25T23:59:59.000Z

    phantom compared favorably to the derived organ absorbed doses measured by the Panasonic thermoluminescence dosimeters and with Monte Carlo â??Nâ?? Particle modeled results. Additionally, a Victoreen 450P pressurized ion chamber measured...

  5. Ectodysplasin signaling in cutaneous appendage development: Dose, duration and diversity

    E-Print Network [OSTI]

    Headon, Denis J.

    2009-01-01T23:59:59.000Z

    The development of several skin appendages is guided by prenatal Ectodysplasin signalling. Cui et al. (this issue, 2009) report on the dose and duration of Ectodysplasin signalling required for the maintenance and morphogenesis ...

  6. An internal dose monitoring program at an academic research institution

    E-Print Network [OSTI]

    Carsten, Keith Eric

    1997-01-01T23:59:59.000Z

    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...

  7. TECHNICAL ADVANCE Therapeutic Dose from a Pyroelectric Electron Accelerator

    E-Print Network [OSTI]

    Danon, Yaron

    interactions with the Faraday cup. Based on these measurements, the dose that this source could deliver cylindrical lithium tantalate crystals, with the cylinder's axis parallel to the axis of polarization. At any

  8. Low dose ionizing radiation detection using conjugated polymers

    SciTech Connect (OSTI)

    Silva, E.A.B.; Borin, J.F.; Nicolucci, P.; Graeff, C.F.O.; Netto, T. Ghilardi; Bianchi, R.F. [Departamento de Fisica e Matematica, FFCLRP, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, SP (Brazil); Centro de Cie circumflex ncias das Imagens e Fisica Medica, Hospital das Clinicas, FMRP, Universidade de Sao Paulo, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, SP (Brazil); Departamento de Engenharia de Sistemas Integraveis, Escola Politecnica da Universidade de Sao Paulo, Av. Prof. Luciano Gualberto, 158, Sao Paulo, SP (Brazil)

    2005-03-28T23:59:59.000Z

    In this work, the effect of gamma radiation on the optical properties of poly[2-methoxy-5-(2{sup '}-ethylhexyloxy)-p-phenylenevinylene] (MEH-PPV) is studied. The samples were irradiated at room temperature with different doses from 0 Gy to 152 Gy using a {sup 60}Co gamma ray source. For thin films, significant changes in the UV-visible spectra were only observed at high doses (>1 kGy). In solution, shifts in absorption peaks are observed at low doses (<10 Gy), linearly dependent on dose. The shifts are explained by conjugation reduction, and possible causes are discussed. Our results indicate that MEH-PPV solution can be used as a dosimeter adequate for medical applications.

  9. accumulated dose measurement: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of sup 2...

  10. adults measuring dose: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    This work describes a pilot study to calculate lung dose from the deposition of radon progeny, via estimates of cumulative exposure derived from in vivo measurements of sup 2...

  11. GROUND-WATER CONTRIBUTION TO DOSE FROM PAST HANFORD OPERATIONS

    SciTech Connect (OSTI)

    Freshley, M. D.; Thorne, P. D.

    1992-01-01T23:59:59.000Z

    The Hanford Environmental Dose Reconstruction (HEOR) Project is being conducted to estimate radiation doses that populations and individuals could have received from Hanford Site operations from 1944 to the present. Four possible pathways by which radionuclides originating in ground water on the Hanford Site could have reached the public have been identified: 1) through contaminated ground water migrating to the Columbia River; 2) through wells on or adjacent to the Hanford Site; 3) through wells that draw some or all of their water from the Columbia River (riparian wells); and 4) through atmospheric deposition resulting in the contamination of a small watershed that, in turn, results in contamination of a shallow well or spring. These four pathways make up the "ground-water pathway ," which is the subject of this study. The objective of the study was to assess the extent to which the groundwater pathway contributed to radiation doses that populations or individuals may have received from past operations at Hanford. The assessment presented in this report was performed by 1) reviewing the extensive ?literature on ground water and ground-water monitoring at Hanford and 2) performing simple calculations to estimate radionuclide concentrations in ground water and the Columbia River resulting from ground-water discharge. Radiation doses that would result from exposure to this ground water and surface water were calculated. The study conclusion is that the ground-water pathways did not contribute significantly to dose. Compared with background radiation in the TriCities {300 mrem/yr), estimated doses are small: 0.02 mrem/yr effective dose equivalent from discharge of contaminated ground water to the Columbia River; 1 mrem/yr effective dose equivalent from Hanford Site wells; 11 mrem/yr effective dose equivalent from riparian wells; and 1 mrem/yr effective dose equivalent from the watershed. Because the estimated doses are so small, the recommendation is that further work on the ground-water pathway be limited to tracking ongoing ground-water studies at the Hanford Site.

  12. Emergency Doses (ED) - Revision 3: A calculator code for environmental dose computations

    SciTech Connect (OSTI)

    Rittmann, P.D.

    1990-12-01T23:59:59.000Z

    The calculator program ED (Emergency Doses) was developed from several HP-41CV calculator programs documented in the report Seven Health Physics Calculator Programs for the HP-41CV, RHO-HS-ST-5P (Rittman 1984). The program was developed to enable estimates of offsite impacts more rapidly and reliably than was possible with the software available for emergency response at that time. The ED - Revision 3, documented in this report, revises the inhalation dose model to match that of ICRP 30, and adds the simple estimates for air concentration downwind from a chemical release. In addition, the method for calculating the Pasquill dispersion parameters was revised to match the GENII code within the limitations of a hand-held calculator (e.g., plume rise and building wake effects are not included). The summary report generator for printed output, which had been present in the code from the original version, was eliminated in Revision 3 to make room for the dispersion model, the chemical release portion, and the methods of looping back to an input menu until there is no further no change. This program runs on the Hewlett-Packard programmable calculators known as the HP-41CV and the HP-41CX. The documentation for ED - Revision 3 includes a guide for users, sample problems, detailed verification tests and results, model descriptions, code description (with program listing), and independent peer review. This software is intended to be used by individuals with some training in the use of air transport models. There are some user inputs that require intelligent application of the model to the actual conditions of the accident. The results calculated using ED - Revision 3 are only correct to the extent allowed by the mathematical models. 9 refs., 36 tabs.

  13. Load attenuating passively adaptive wind turbine blade

    DOE Patents [OSTI]

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

    2003-01-01T23:59:59.000Z

    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.

  14. Load attenuating passively adaptive wind turbine blade

    DOE Patents [OSTI]

    Veers, Paul S.; Lobitz, Donald W.

    2003-01-07T23:59:59.000Z

    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.

  15. Model Driven Mutation Applied to Adaptative Systems Testing

    E-Print Network [OSTI]

    Bartel, Alexandre; Munoz, Freddy; Klein, Jacques; Mouelhi, Tejeddine; Traon, Yves Le

    2012-01-01T23:59:59.000Z

    Dynamically Adaptive Systems modify their behav- ior and structure in response to changes in their surrounding environment and according to an adaptation logic. Critical sys- tems increasingly incorporate dynamic adaptation capabilities; examples include disaster relief and space exploration systems. In this paper, we focus on mutation testing of the adaptation logic. We propose a fault model for adaptation logics that classifies faults into environmental completeness and adaptation correct- ness. Since there are several adaptation logic languages relying on the same underlying concepts, the fault model is expressed independently from specific adaptation languages. Taking benefit from model-driven engineering technology, we express these common concepts in a metamodel and define the operational semantics of mutation operators at this level. Mutation is applied on model elements and model transformations are used to propagate these changes to a given adaptation policy in the chosen formalism. Preliminary resul...

  16. Automated Dose and Dopant Level Monitoring by SIMS

    SciTech Connect (OSTI)

    Maul, Hans; Loibl, Norbert; Ehrke, Ulrich [CAMECA GmbH Bruckmannring 40, 85764 Oberschleissheim (Germany); Merkulov, Alex; Peres, Paula; Schuhmacher, Michel [CAMECA SA 103 Blvd. St.-Denis, Courbevoie 92403 (France)

    2006-11-13T23:59:59.000Z

    Full wafer SIMS without breaking the 300mm wafer has the advantage of saving cost and speeding-up response time. A variety of performance examples for B, As and P implants in Si and for B levels in SiGe is shown for both Cameca tools, the quadrupole based SIMS 4600 and the magnet based IMS Wf. Dose mapping and dose monitoring with an RSD around 0.5% are demonstrated and the added value of dopant profiles is illustrated.

  17. Dose reduction improvements in storage basins of spent nuclear fuel

    SciTech Connect (OSTI)

    Huang, Fan-Hsiung F.

    1997-08-13T23:59:59.000Z

    Spent nuclear fuel in storage basins at the Hanford Site has corroded and contaminated basin water, which has leaked into the soil; the fuel also had deposited a layer of radioactive sludge on basin floors. The SNF is to be removed from the basins to protect the nearby Columbia River. Because the radiation level is high, measures have been taken to reduce the background dose rate to as low as reasonably achievable (ALARA) to prevent radiation doses from becoming the limiting factor for removal of the SW in the basins to long-term dry storage. All activities of the SNF Project require application of ALARA principles for the workers. On the basis of these principles dose reduction improvements have been made by first identifying radiological sources. Principal radiological sources in the basin are basin walls, basin water, recirculation piping and equipment. Dose reduction activities focus on cleaning and coating basin walls to permit raising the water level, hydrolasing piping, and placing lead plates. In addition, the transfer bay floor will be refinished to make decontamination easier and reduce worker exposures in the radiation field. The background dose rates in the basin will be estimated before each task commences and after it is completed; these dose reduction data will provide the basis for cost benefit analysis.

  18. Electrical activation and spin coherence of ultra low dose antimony implants in silicon

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    and spin coherence of ultra low dose antimony implants inClara, CA 95054 We implanted ultra low doses (0.2 to 210 11100 nm, corresponding to ultra low ion implantation doses of

  19. Adaptive protocols for mobile ad hoc networks

    E-Print Network [OSTI]

    Holland, Gavin Douglas

    2005-02-17T23:59:59.000Z

    . We investigate new link layer mechanisms that dynamically monitor and adapt to changes in link quality, including a protocol that uses common control messages to form a tight feedback control loop for adaptation of the link data rate to best match... of the presence of multirate links. We then investigate the performance of iv TCP, showing how communication outages caused by link failures and routing delays can be very detrimental to its performance. In response, we present a solution to this problem that uses...

  20. INTEGRATED CODES FOR ESTIMATING ENVIRONMENTAL ACCUMULATION ANd INDIVIDUAL DOSE FROM PAST HANFORD ATMOSPHERIC RELEASES Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Ikenberry, T. A.; Burnett, R. A.; Napier, B. A.; Reitz, N. A.; Shipler, D. B.

    1992-02-01T23:59:59.000Z

    Preliminary radiation doses were estimated and reported during Phase I of the Hanford Environmental Dose Reconstruction (HEDR) Project. As the project has progressed, additional information regarding the magnitude and timing of past radioactive releases has been developed, and the general scope of the required calculations has been enhanced. The overall HEDR computational model for computing doses attributable to atmospheric releases from Hanford Site operations is called HEDRIC (Hanford Environmental Dose Reconstruction Integrated Codes). It consists of four interrelated models: source term, atmospheric transport, environmental accumulation, and individual dose. The source term and atmospheric transport models are documented elsewhere. This report describes the initial implementation of the design specifications for the environmental accumulation model and computer code, called DESCARTES (Dynamic EStimates of Concentrations and Accumulated Radionuclides in Terrestrial Environments), and the individual dose model and computer code, called CIDER (Calculation of Individual Doses from Environmental Radionuclides). The computations required of these models and the design specifications for their codes were documented in Napier et al. (1992). Revisions to the original specifications and the basis for modeling decisions are explained. This report is not the final code documentation but gives the status of the model and code development to date. Final code documentation is scheduled to be completed in FY 1994 following additional code upgrades and refinements. The user's guide included in this report describes the operation of the environmental accumulation and individual dose codes and associated pre- and post-processor programs. A programmer's guide describes the logical structure of the programs and their input and output files.

  1. A Fully Automated Method for CT-on-Rails-Guided Online Adaptive Planning for Prostate Cancer Intensity Modulated Radiation Therapy

    SciTech Connect (OSTI)

    Li, Xiaoqiang; Quan, Enzhuo M.; Li, Yupeng [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Pan, Xiaoning [Department of Radiation Oncology, University of Texas Health Science Center at Tyler, Tyler, Texas (United States); Zhou, Yin [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Wang, Xiaochun [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Du, Weiliang [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kudchadker, Rajat J.; Johnson, Jennifer L. [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kuban, Deborah A.; Lee, Andrew K. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhang, Xiaodong, E-mail: xizhang@mdanderson.org [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2013-08-01T23:59:59.000Z

    Purpose: This study was designed to validate a fully automated adaptive planning (AAP) method which integrates automated recontouring and automated replanning to account for interfractional anatomical changes in prostate cancer patients receiving adaptive intensity modulated radiation therapy (IMRT) based on daily repeated computed tomography (CT)-on-rails images. Methods and Materials: Nine prostate cancer patients treated at our institution were randomly selected. For the AAP method, contours on each repeat CT image were automatically generated by mapping the contours from the simulation CT image using deformable image registration. An in-house automated planning tool incorporated into the Pinnacle treatment planning system was used to generate the original and the adapted IMRT plans. The cumulative dosevolume histograms (DVHs) of the target and critical structures were calculated based on the manual contours for all plans and compared with those of plans generated by the conventional method, that is, shifting the isocenters by aligning the images based on the center of the volume (COV) of prostate (prostate COV-aligned). Results: The target coverage from our AAP method for every patient was acceptable, while 1 of the 9 patients showed target underdosing from prostate COV-aligned plans. The normalized volume receiving at least 70 Gy (V{sub 70}), and the mean dose of the rectum and bladder were reduced by 8.9%, 6.4 Gy and 4.3%, 5.3 Gy, respectively, for the AAP method compared with the values obtained from prostate COV-aligned plans. Conclusions: The AAP method, which is fully automated, is effective for online replanning to compensate for target dose deficits and critical organ overdosing caused by interfractional anatomical changes in prostate cancer.

  2. Does administering iodine in radiological procedures increase patient doses?

    SciTech Connect (OSTI)

    He, Wenjun; Yao, Hai, E-mail: haiyao@clemson.edu [Clemson-MUSC Bioengineering Program, Department of Bioengineering, Clemson University, Charleston, South Carolina 29425 (United States); Huda, Walter; Mah, Eugene [Department of Radiology and Radiological Science, Medical University of South Carolina (MUSC), Charleston, South Carolina 29425 (United States)

    2014-11-01T23:59:59.000Z

    Purpose: The authors investigated the changes in the pattern of energy deposition in tissue equivalent phantoms following the introduction of iodinated contrast media. Methods: The phantom consisted of a small contrast sphere, filled with water or iodinated contrast, located at the center of a 28 cm diameter water sphere. Monte Carlo simulations were performed using MCNP5 codes, validated by simulating irradiations with analytical solutions. Monoenergetic x-rays ranging from 35 to 150 keV were used to simulate exposures to spheres containing contrast agent with iodine concentrations ranging from 1 to 100 mg/ml. Relative values of energy imparted to the contrast sphere, as well as to the whole phantom, were calculated. Changes in patterns of energy deposition around the contrast sphere were also investigated. Results: Small contrast spheres can increase local absorbed dose by a factor of 13, but the corresponding increase in total energy absorbed was negligible (<1%). The highest localized dose increases were found to occur at incident photon energies of about 60 keV. For a concentration of about 10 mg/ml, typical of clinical practice, localized absorbed doses were generally increased by about a factor of two. At this concentration of 10 mg/ml, the maximum increase in total energy deposition in the phantom was only 6%. These simulations demonstrated that increases in contrast sphere doses were offset by corresponding dose reductions at distal and posterior locations. Conclusions: Adding iodine can result in values of localized absorbed dose increasing by more than an order of magnitude, but the total energy deposition is generally very modest (i.e., <10%). Their data show that adding iodine primarily changes the pattern of energy deposition in the irradiated region, rather than increasing patient doses per se.

  3. Adaptive Training for Large Vocabulary Continuous

    E-Print Network [OSTI]

    Hain, Thomas

    Adaptive Training for Large Vocabulary Continuous Speech Recognition Kai Yu Hughes Hall College for the degree of Doctor of Philosophy #12;ii Summary In recent years, there has been a trend towards training is to train hidden Markov models (HMMs) on the whole data set as if all data comes from a single acoustic

  4. Semantic Web Technologies for the Adaptive Web

    E-Print Network [OSTI]

    Nejdl, Wolfgang

    23 Semantic Web Technologies for the Adaptive Web Peter Dolog1 and Wolfgang Nejdl2 1 Department.de Abstract. Ontologies and reasoning are the key terms brought into focus by the semantic web community. Formal representation of ontologies in a common data model on the web can be taken as a foundation

  5. Provenance Meets Adaptive Hypermedia Evgeny Knutov

    E-Print Network [OSTI]

    De Bra, Paul

    Provenance Meets Adaptive Hypermedia Evgeny Knutov Department of Computer Science Eindhoven University of Technology P.O. Box 513, 5600 MB Eindhoven, the Netherlands e.knutov@tue.nl Paul De Bra Department of Computer Science Eindhoven University of Technology P.O. Box 513, 5600 MB Eindhoven

  6. A Computational Model for Adaptive Emotion Regulation

    E-Print Network [OSTI]

    Treur, Jan

    A Computational Model for Adaptive Emotion Regulation Tibor Bosse, Matthijs Pontier, and Jan Treur} Abstract. Emotion regulation describes how a subject can use certain strategies to affect emotion response levels. Usually, models for emotion regulation as- sume mechanisms based on feedback loops that indicate

  7. Adaptive Scheduling Algorithms for Planet Searches

    E-Print Network [OSTI]

    Eric B. Ford

    2007-12-17T23:59:59.000Z

    High-precision radial velocity planet searches have surveyed over ~2000 nearby stars and detected over ~200 planets. While these same stars likely harbor many additional planets, they will become increasingly challenging to detect, as they tend to have relatively small masses and/or relatively long orbital periods. Therefore, observers are increasing the precision of their observations, continuing to monitor stars over decade timescales, and also preparing to survey thousands more stars. Given the considerable amounts of telescope time required for such observing programs, it is important use the available resources as efficiently as possible. Previous studies have found that a wide range of predetermined scheduling algorithms result in planet searches with similar sensitivities. We have developed adaptive scheduling algorithms which have a solid basis in Bayesian inference and information theory and also are computationally feasible for modern planet searches. We have performed Monte Carlo simulations of plausible planet searches to test the power of adaptive scheduling algorithms. Our simulations demonstrate that planet searches performed with adaptive scheduling algorithms can simultaneously detect more planets, detect less massive planets, and measure orbital parameters more accurately than comparable surveys using a non-adaptive scheduling algorithm. We expect that these techniques will be particularly valuable for the N2K radial velocity planet search for short-period planets as well as future astrometric planet searches with the Space Interferometry Mission which aim to detect terrestrial mass planets.

  8. A Middleware Framework for the Adaptive Home

    E-Print Network [OSTI]

    Dommel, Hans-Peter

    -friendly access to customized energy-aware home control, as well as the basic ambient intelligence to make a home adapt to user behavior and environmental constraints. Keywords. Network middleware for smart homes behavior. Newer developments in outfitting homes with powerful telematic intelligence [3, 4] catering

  9. Adaptive wavelet deconvolution for strongly mixing sequences

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Adaptive wavelet deconvolution for strongly mixing sequences Christophe Chesneau Abstract square error over Besov balls, we explore the performances of two wavelet estimators: a standard linear, Strongly mixing, Adap- tivity, Wavelets, Hard thresholding. AMS 2000 Subject Classifications: 62G07, 62G20

  10. IBM Software Data Sheet IBM adaptive threat

    E-Print Network [OSTI]

    IBM Software Data Sheet IBM adaptive threat protection Stay ahead of security threats with a state-of-the-art network protection engine Highlights Identify high-risk threats and zero-day attacks with protocol-based, behavioral anomaly detection Protect end users against the latest web-based threats, such as SQL injection

  11. Adaptive, full-spectrum solar energy system

    DOE Patents [OSTI]

    Muhs, Jeffrey D.; Earl, Dennis D.

    2003-08-05T23:59:59.000Z

    An adaptive full spectrum solar energy system having at least one hybrid solar concentrator, at least one hybrid luminaire, at least one hybrid photobioreactor, and a light distribution system operably connected to each hybrid solar concentrator, each hybrid luminaire, and each hybrid photobioreactor. A lighting control system operates each component.

  12. Adaptation in constant utility nonstationary environments

    E-Print Network [OSTI]

    Littman, Michael L.

    stationary environments are so pathological. Even if the environment, when viewed as a monolithic function, may of the results created by the organism over some given lifespan determines the organism's fitness. The nasty, the fitness produced by any single mapping will be at the chance level. The adaptive challenge is to produce

  13. Energy dissipation in an adaptive molecular circuit

    E-Print Network [OSTI]

    Shou-Wen Wang; Yueheng Lan; Lei-Han Tang

    2015-05-28T23:59:59.000Z

    The ability to monitor nutrient and other environmental conditions with high sensitivity is crucial for cell growth and survival. Sensory adaptation allows a cell to recover its sensitivity after a transient response to a shift in the strength of extracellular stimulus. The working principles of adaptation have been established previously based on rate equations which do not consider fluctuations in a thermal environment. Recently, G. Lan et al. (Nature Phys., 8:422-8, 2012) performed a detailed analysis of a stochastic model for the E. coli sensory network. They showed that accurate adaptation is possible only when the system operates in a nonequilibrium steady-state (NESS). They further proposed an energy-speed-accuracy (ESA) trade-off relation. We present here analytic results on the NESS of the model through a mapping to a one-dimensional birth-death process. An exact expression for the entropy production rate is also derived. Based on these results, we are able to discuss the ESA relation in a more general setting. Our study suggests that the adaptation error can be reduced exponentially as the methylation range increases. Finally, we show that a nonequilibrium phase transition exists in the infinite methylation range limit, despite the fact that the model contains only two discrete variables.

  14. CLIMATE CHANGE ADAPTATIONS FOR LOCAL WATER MANAGEMENT

    E-Print Network [OSTI]

    CLIMATE CHANGE ADAPTATIONS FOR LOCAL WATER MANAGEMENT IN THE SAN FRANCISCO BAY AREA A White Paper from the California Energy Commission's California Climate Change Center JULY 2012 CEC Climate change will affect both sea level and the temporal and spatial distribution of runoff

  15. An Infrastructure for Adaptive Dynamic Optimization

    E-Print Network [OSTI]

    Amarasinghe, Saman

    An Infrastructure for Adaptive Dynamic Optimization Derek Bruening, Timothy Garnett, and Saman,timothyg,saman}@lcs.mit.edu Abstract Dynamic optimization is emerging as a promising ap- proach to overcome many of the obstacles static optimizations, there are very few for developing dynamic optimizations. We present a framework

  16. Grid adaptation for multiscale plasma simulations

    E-Print Network [OSTI]

    Ito, Atsushi

    Grid adaptation for multiscale plasma simulations Gian Luca Delzanno Los Alamos National Laboratory In collaboration with L. Chacon and J.M. Finn #12;delzanno@lanl.gov Outline Introduction and motivation Grid tests New directions Conclusions #12;delzanno@lanl.gov Outline Introduction and motivation Grid

  17. Climate Change Basics: Science, Adaptation, & Mitigation

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

    Science Global atmospheric concentrations of carbon dioxide, methane and nitrous oxide have increased from ice cores spanning many thousands of years. The global increases in carbon dioxide concentrationClimate Change Basics: Science, Adaptation, & Mitigation with a Family Forest Perspective Baylor

  18. Adaptation, Speciation, and Convergence: A Hierarchical Analysis of Adaptive Radiation in Caribbean Anolis Lizards

    E-Print Network [OSTI]

    Losos, Jonathan B.; Glor, Richard E.; Kolbe, Jason J.; Nicholson, Kirsten

    2006-05-01T23:59:59.000Z

    Caribbean Anolis lizards are a classic case of adaptive radiation, repeated four times across islands of the Greater Antilles. On each island, very similar patterns of evolutionary divergence have occurred, resulting in the evolution of the same set...

  19. The Complexity of Adaptation to Climate Change. Exploring adaptation in Rio Grande, Ecuador

    E-Print Network [OSTI]

    Argudo, Cristina

    2014-11-27T23:59:59.000Z

    Climate change has become one of the most challenging problems in terms of development, having adverse effects in populations that are already vulnerable to other stressors. At present, the importance of adaptation to climate change has been widely...

  20. Funding for adaptation to climate change : the case of Surat

    E-Print Network [OSTI]

    Patel, Toral

    2014-01-01T23:59:59.000Z

    The need for cities to adapt to climate change is widely acknowledged, yet the question of adaptation finance remains uncertain. Unable to access global climate funds, cities must seek out alternative sources to support ...

  1. Learning from Monitoring & Evaluation a blueprint for an adaptive organisation

    E-Print Network [OSTI]

    Learning from Monitoring & Evaluation a blueprint for an adaptive organisation Learning from Monitoring & Evaluation a blueprint for an adaptive organisation Jake Morris and Anna Lawrence Social & Economic Research Group, Forest Research Aim and structure Learning is an essential characteristic

  2. Adaptive array antenna design for wireless communication systems

    E-Print Network [OSTI]

    Noordin, Nurul Hazlina

    2013-11-28T23:59:59.000Z

    Adaptive array antennas use has been limited to non-commercial applications due to their high cost and hardware complexity. The implementation cost of adaptive array antennas can be kept to a minimum by using cost effective ...

  3. Evaluation and Adaptation of 5-Cycle Fuel Economy Testing and...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Adaptation of 5-Cycle Fuel Economy Testing and Calculations for HEVs and PHEVs Evaluation and Adaptation of 5-Cycle Fuel Economy Testing and Calculations for HEVs and PHEVs 2012...

  4. adaptive process control: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 ADAPTIVE OPTICS CONTROL FOR LASER MATERIAL PROCESSING Mathematics Websites Summary: ADAPTIVE OPTICS...

  5. Geometric Structure of the Adaptive Controller of the Human Arm

    E-Print Network [OSTI]

    Shadmehr, Reza

    1993-07-01T23:59:59.000Z

    The objects with which the hand interacts with may significantly change the dynamics of the arm. How does the brain adapt control of arm movements to this new dynamic? We show that adaptation is via composition of a ...

  6. Adaptive Treatment Strategies Getting SMART About Developing Individualized

    E-Print Network [OSTI]

    Murphy, Susan A.

    Other names are dynamic treatment regimes, treatment algorithms, stepped care models, expert systems: prevent relapse to alcohol abuse · Critical treatment decisions: which treatment to provide first?; which1 Adaptive Treatment Strategies Getting SMART About Developing Individualized Sequences of Adaptive

  7. adaptive fourier analyzer: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    view or analyze the problem in n ways (n >2) Though we have defined these n- adaptive fuzzy models theorectically we are not in a position to get a n-adaptive fuzzy model for n...

  8. Accelerated Adaptive Markov Chain for Partition Function Computation

    E-Print Network [OSTI]

    Keinan, Alon

    Accelerated Adaptive Markov Chain for Partition Function Computation Stefano Ermon, Carla P. Gomes Ithaca NY 14853, U.S.A. Abstract We propose a novel Adaptive Markov Chain Monte Carlo algorithm

  9. Urban climate resilience : a global assessment of city adaptation plans

    E-Print Network [OSTI]

    Katich, Kristina Noel

    2009-01-01T23:59:59.000Z

    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 ...

  10. Climate Change Adaptation: A Collective Action Perspective on Federalism Considerations

    E-Print Network [OSTI]

    Glicksman, Robert L.; Levy, Richard E.

    2010-01-01T23:59:59.000Z

    adaptation to minimize the adverse effects of climate change. Climate change adaptation is designed to increase the resilience of natural and human ecosystems to the threats posed by a changing environment. Although an extensive literature concerning...

  11. Performance of Adaptive DualDropping ILUT Preconditioners in Semiconductor

    E-Print Network [OSTI]

    Zhang, Jun

    Performance of Adaptive DualDropping ILUT Preconditioners in Semiconductor Dopant Diffusion for iterative solution of sparse linear systems arising in semiconductor dopant diffusion modeling resolution, timestep in the adaptive ODE integrator and the problem physics. Key words: semiconductor TCAD

  12. Adaptive Robust Control of Robot Manipulators: Theory and Comparative Experiments

    E-Print Network [OSTI]

    Yao, Bin

    of the system such as gravitational load vary from a task to another, and, may not be precisely known in advance-based or direct adaptive control 21 , in which adaptation laws are used to adjust controller gains instead

  13. The Binding of Learning to Action in Motor Adaptation

    E-Print Network [OSTI]

    Gonzalez Castro, Luis Nicolas

    In motor tasks, errors between planned and actual movements generally result in adaptive changes which reduce the occurrence of similar errors in the future. It has commonly been assumed that the motor adaptation arising ...

  14. PRECEDENTS FOR AUTHORIZATION OF CONTENTS USING DOSE RATE MEASUREMENTS

    SciTech Connect (OSTI)

    Abramczyk, G.; Bellamy, S.; Nathan, S.; Loftin, B.

    2012-06-05T23:59:59.000Z

    For the transportation of Radioactive Material (RAM) packages, the requirements for the maximum allowed dose rate at the package surface and in its vicinity are given in Title 10 of the Code of Federal Regulations, Section 71.47. The regulations are based on the acceptable dose rates to which the public, workers, and the environment may be exposed. As such, the regulations specify dose rates, rather than quantity of radioactive isotopes and require monitoring to confirm the requirements are met. 10CFR71.47 requires that each package of radioactive materials offered for transportation must be designed and prepared for shipment so that under conditions normally incident to transportation the radiation level does not exceed 2 mSv/h (200 mrem/h) at any point on the external Surface of the package, and the transport index does not exceed 10. Before shipment, the dose rate of the package is determined by measurement, ensuring that it conforms to the regulatory limits, regardless of any analyses. This is the requirement for all certified packagings. This paper discusses the requirements for establishing the dose rates when shipping RAM packages and the precedents for meeting these requirements by measurement.

  15. Optimal adaptive control of cascading power grid failures

    E-Print Network [OSTI]

    Daniel Bienstock

    2010-12-17T23:59:59.000Z

    Dec 17, 2010 ... Abstract: We describe experiments with parallel algorithms for computing adaptive controls for attenuating power grid cascading failures.

  16. Genomic islands predict functional adaptation in marine actinobacteria

    E-Print Network [OSTI]

    Penn, Kevin

    2010-01-01T23:59:59.000Z

    Ecological adaptations among bacterial populations have been linked to genomic islands, strain-specific regions of DNA that house

  17. BIA Request for Proposals for Climate Adaptation Grants for Tribes

    Broader source: Energy.gov [DOE]

    Download the Bureau of Indian Affairs Request for Proposals for Climate Adaptation Grants for Tribes, due November 29.

  18. Communication adapter for use with a drilling component

    DOE Patents [OSTI]

    Hall, David R. (Provo, UT); Pixton, David S. (Lehi, UT); Hall; Jr.; H. Tracy (Provo, UT); Bradford, Kline (Orem, UT); Rawle, Michael (Springville, UT)

    2007-04-03T23:59:59.000Z

    A communication adapter is disclosed that provides for removable attachment to a drilling component when the drilling component is not actively drilling and for communication with an integrated transmission system in the drilling component. The communication adapter comprises a data transmission coupler that facilitates communication between the drilling component and the adapter, a mechanical coupler that facilitates removable attachment of the adapter to the drilling component, and a data interface.

  19. Automated Web Page Synthesis in Adaptive Web Systems

    E-Print Network [OSTI]

    Ghorbani, Ali

    Automated Web Page Synthesis in Adaptive Web Systems Hossein Sadat and Ali Ghorbani Intelligent, Canada {t15h7,ghorbani}@unb.ca Abstract. An adaptive Web system adapts the Web pages to its users, based of the system. In this paper, we formalize dynamic generation of Web pages and refer to it as Web page synthesis

  20. MEDIA RESOURCES ADAPTATION FOR LIMITED DEVICES TAYEB LEMLOUMA1

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    MEDIA RESOURCES ADAPTATION FOR LIMITED DEVICES TAYEB LEMLOUMA1 ; NABIL LAYADA1 1 WAM Project, INRIA.Lemlouma@inrialpes.fr; Nabil.Layaida@inrialpes.fr In this paper, we define a framework for media resources manipulation in an adaptive content delivery system. We discuss the media resources manipulation in an adaptation

  1. An Adaptive Kalman Filter for Removing Baseline Wandering in ECG

    E-Print Network [OSTI]

    Povinelli, Richard J.

    An Adaptive Kalman Filter for Removing Baseline Wandering in ECG Signals MA Mneimneh, EE Yaz, MT to baseline removal. This paper proposes an adaptive Kalman filter for the real time re- moval of baseline is used with an adaptive Kalman filter to estimate the state variables, including the baseline wandering

  2. Adaptive Power Controlled Routing for Underwater Sensor Networks

    E-Print Network [OSTI]

    Zhou, Shengli

    Adaptive Power Controlled Routing for Underwater Sensor Networks Manal Al-Bzoor, Yibo Zhu, Jun Liu of an in- terest packet sent by sink nodes. We use adaptive power control to send at high power level the sink nodes using shortest end to end paths. By using adaptive power control over concentric layered

  3. Semantic Multimedia Document Adaptation with Functional Annotations Sebastien Laborie

    E-Print Network [OSTI]

    Joseph Fourier Grenoble-I, Universit

    Semantic Multimedia Document Adaptation with Functional Annotations Sebastien Laborie IRIT Paul of presentation contexts for multimedia documents requires the adaptation of document specifica- tions. In an earlier work, we have proposed a seman- tic adaptation framework for multimedia documents. This framework

  4. Some Computational Problems Arising in Adaptive Optics Imaging Systems

    E-Print Network [OSTI]

    Plemmons, Robert J.

    Some Computational Problems Arising in Adaptive Optics Imaging Systems Robert J. Plemmons \\Lambda numerical linear algebra tech niques in adaptive optics imaging control computations. Realtime adaptive optics is a means for enhancing the resolution of ground based, optical telescopes beyond the limits

  5. Checking Sequence Construction Using Adaptive and Preset Distinguishing Sequences

    E-Print Network [OSTI]

    Jourdan, Guy-Vincent

    Checking Sequence Construction Using Adaptive and Preset Distinguishing Sequences Robert M. Hierons of a preset dis- tinguishing sequence for constructing checking sequences. It has been shown that an adaptive distinguishing sequence is sufficient for these methods. This result is significant because adaptive

  6. Grid adaptation for multiscale plasma simulations Gian Luca Delzanno

    E-Print Network [OSTI]

    Ito, Atsushi

    Grid adaptation for multiscale plasma simulations Gian Luca Delzanno Los Alamos National Laboratory tools need to be developed to bridge the gap between these disparate scales. Grid adaptation is one of such tools, useful to address multiple length scales, and we present a new powerful grid adaptation method

  7. Phenotypic plasticity facilitates recurrent rapid adaptation to introduced predators

    E-Print Network [OSTI]

    Pfrender, Michael

    Phenotypic plasticity facilitates recurrent rapid adaptation to introduced predators Alison G) A central role for phenotypic plasticity in adaptive evolution is often posited yet lacks empirical support of preexisting developmental pathways, producing rapid adaptive change. We examined the role of plasticity

  8. Adaptation Control in Adaptive Hypermedia Systems Hongjing Wu, Paul De Bra, Ad Aerts, GeertJan Houben

    E-Print Network [OSTI]

    De Bra, Paul

    model for the architecture of adaptive hypermedia applications: AHAM (for Adaptive Hypermedia Application Model) [DHW99], which is an extension of the Dexter hypermedia reference model [HS90, HS94]. AHAM

  9. Adaptation Control in Adaptive Hypermedia Systems Hongjing Wu, Paul De Bra, Ad Aerts, Geert-Jan Houben

    E-Print Network [OSTI]

    Houben, Geert-Jan

    model for the architecture of adaptive hypermedia applications: AHAM (for Adaptive Hypermedia Application Model) [DHW99], which is an extension of the Dexter hypermedia reference model [HS90, HS94]. AHAM

  10. Radiation Dose-Volume Effects and the Penile Bulb

    SciTech Connect (OSTI)

    Roach, Mack, E-mail: mroach@radonc.ucsf.ed [Department of Radiation Oncology, University of California-San Francisco, San Francisco, CA (United States); Nam, Jiho [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Gagliardi, Giovanna [Department of Medical Physics, Karolinska University Hospital and Karolinska Institutet, Stockholm (Sweden); El Naqa, Issam; Deasy, Joseph O. [Department of Radiation Oncology, School of Medicine, Washington University in St. Louis, St. Louis, MO (United States); Marks, Lawrence B. [Department of Radiation Oncology, University of North Carolina at Chapel Hill, Chapel Hill, NC (United States)

    2010-03-01T23:59:59.000Z

    The dose, volume, and clinical outcome data for penile bulb are reviewed for patients treated with external-beam radiotherapy. Most, but not all, studies find an association between impotence and dosimetric parameters (e.g., threshold doses) and clinical factors (e.g., age, comorbid diseases). According to the data available, it is prudent to keep the mean dose to 95% of the penile bulb volume to <50 Gy. It may also be prudent to limit the D70 and D90 to 70 Gy and 50 Gy, respectively, but coverage of the planning target volume should not be compromised. It is acknowledged that the penile bulb may not be the critical component of the erectile apparatus, but it seems to be a surrogate for yet to be determined structure(s) critical for erectile function for at least some techniques.

  11. Estimation of food consumption. Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Callaway, J.M. Jr.

    1992-04-01T23:59:59.000Z

    The research reported in this document was conducted as a part of the Hanford Environmental Dose Reconstruction (HEDR) Project. The objective of the HEDR Project is to estimate the radiation doses that people could have received from operations at the Hanford Site. Information required to estimate these doses includes estimates of the amounts of potentially contaminated foods that individuals in the region consumed during the study period. In that general framework, the objective of the Food Consumption Task was to develop a capability to provide information about the parameters of the distribution(s) of daily food consumption for representative groups in the population for selected years during the study period. This report describes the methods and data used to estimate food consumption and presents the results developed for Phase I of the HEDR Project.

  12. Prediction of the mortality dose-response relationship in man

    SciTech Connect (OSTI)

    Morris, M.D.; Jones, T.D.

    1987-01-01T23:59:59.000Z

    Based upon an extensive data base including 100 separate animal studies, an estimate of the mortality dose-response relationship due to continuous photon radiation is predicted for 70 kg man. The model used in this prediction exercise includes fixed terms accounting for effects of body weight and dose rate, and random terms accounting for inter- and intra-species variation and experimental error. Point predictions and 95% prediction intervals are given for the LD/sub 05/, LD/sub 10/, LD/sub 25/, LD/sub 50/, LD/sub 75/, LD/sub 90/, and LD/sub 95/, for dose rates ranging from 1 to 50 R/min. 6 refs., 5 tabs.

  13. HDRMC, an accelerated Monte Carlo dose calculator for high dose rate brachytherapy with CT-compatible applicators

    SciTech Connect (OSTI)

    Chibani, Omar, E-mail: omar.chibani@fccc.edu; C-M Ma, Charlie [Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)] [Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111 (United States)

    2014-05-15T23:59:59.000Z

    Purpose: To present a new accelerated Monte Carlo code for CT-based dose calculations in high dose rate (HDR) brachytherapy. The new code (HDRMC) accounts for both tissue and nontissue heterogeneities (applicator and contrast medium). Methods: HDRMC uses a fast ray-tracing technique and detailed physics algorithms to transport photons through a 3D mesh of voxels representing the patient anatomy with applicator and contrast medium included. A precalculated phase space file for the{sup 192}Ir source is used as source term. HDRM is calibrated to calculated absolute dose for real plans. A postprocessing technique is used to include the exact density and composition of nontissue heterogeneities in the 3D phantom. Dwell positions and angular orientations of the source are reconstructed using data from the treatment planning system (TPS). Structure contours are also imported from the TPS to recalculate dose-volume histograms. Results: HDRMC was first benchmarked against the MCNP5 code for a single source in homogenous water and for a loaded gynecologic applicator in water. The accuracy of the voxel-based applicator model used in HDRMC was also verified by comparing 3D dose distributions and dose-volume parameters obtained using 1-mm{sup 3} versus 2-mm{sup 3} phantom resolutions. HDRMC can calculate the 3D dose distribution for a typical HDR cervix case with 2-mm resolution in 5 min on a single CPU. Examples of heterogeneity effects for two clinical cases (cervix and esophagus) were demonstrated using HDRMC. The neglect of tissue heterogeneity for the esophageal case leads to the overestimate of CTV D90, CTV D100, and spinal cord maximum dose by 3.2%, 3.9%, and 3.6%, respectively. Conclusions: A fast Monte Carlo code for CT-based dose calculations which does not require a prebuilt applicator model is developed for those HDR brachytherapy treatments that use CT-compatible applicators. Tissue and nontissue heterogeneities should be taken into account in modern HDR brachytherapy planning.

  14. Phase 1 of the Hanford Environmental Dose Reconstruction Project

    SciTech Connect (OSTI)

    Not Available

    1990-07-20T23:59:59.000Z

    For more than 40 years, the US government made plutonium for nuclear weapons at the Hanford Site in southeastern Washington State. Radioactive materials were released to both the air and water from Hanford. People could have been exposed to these materials, called radionuclides. The Hanford Environmental Dose Reconstruction (HEDR) Project is a multi-year scientific study to estimate the radiation doses the public may have received as a results of these releases. The study began in 1988. During the first phase, scientists began to develop and test methods for reconstructing the radiation doses. To do this, scientists found or reconstructed information about the amount and type of radionuclides that were released from Hadford facilities, where they traveled in environment, and how they reached people. Information about the people who could have been exposed was also found or reconstructed. Scientists then developed a computer model that can estimate doses from radiation exposure received many years ago. All the information that had been gathered was fed into the computer model. Then scientists did a test run'' to see whether the model was working properly. As part of its test run,'' scientists asked the computer model to generate two types of preliminary results: amounts of radionuclides in the environment (air, soil, pasture grass, food, and milk) and preliminary doses people could have received from all the routes of radiation exposure, called exposure pathways. Preliminary dose estimates were made for categories of people who shared certain characteristics and for the Phase 1 population as a whole. 26 refs., 48 figs.

  15. Intensity Modulated Radiation Therapy With Dose Painting to Treat Rhabdomyosarcoma

    SciTech Connect (OSTI)

    Yang, Joanna C.; Dharmarajan, Kavita V. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wexler, Leonard H. [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Pediatrics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); La Quaglia, Michael P. [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Happersett, Laura [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2012-11-01T23:59:59.000Z

    Purpose: To examine local control and patterns of failure in rhabdomyosarcoma patients treated with intensity modulated radiation therapy (RT) with dose painting (DP-IMRT). Patients and Methods: A total of 41 patients underwent DP-IMRT with chemotherapy for definitive treatment. Nineteen also underwent surgery with or without intraoperative RT. Fifty-six percent had alveolar histologic features. The median interval from beginning chemotherapy to RT was 17 weeks (range, 4-25). Very young children who underwent second-look procedures with or without intraoperative RT received reduced doses of 24-36 Gy in 1.4-1.8-Gy fractions. Young adults received 50.4 Gy to the primary tumor and lower doses of 36 Gy in 1.8-Gy fractions to at-risk lymph node chains. Results: With 22 months of median follow-up, the actuarial local control rate was 90%. Patients aged {<=}7 years who received reduced overall and fractional doses had 100% local control, and young adults had 79% (P=.07) local control. Three local failures were identified in young adults whose primary target volumes had received 50.4 Gy in 1.8-Gy fractions. Conclusions: DP-IMRT with lower fractional and cumulative doses is feasible for very young children after second-look procedures with or without intraoperative RT. DP-IMRT is also feasible in adolescents and young adults with aggressive disease who would benefit from prophylactic RT to high-risk lymph node chains, although dose escalation might be warranted for improved local control. With limited follow-up, it appears that DP-IMRT produces local control rates comparable to those of sequential IMRT in patients with rhabdomyosarcoma.

  16. SU-E-J-153: MRI Based, Daily Adaptive Radiotherapy for Rectal Cancer: Contour Adaptation

    SciTech Connect (OSTI)

    Kleijnen, J; Burbach, M; Verbraeken, T; Weggers, R; Zoetelief, A; Reerink, O; Lagendijk, J; Raaymakers, B; Asselen, B [University Medical Center Utrecht, Utrecht (Netherlands)

    2014-06-01T23:59:59.000Z

    Purpose: A major hurdle in adaptive radiotherapy is the adaptation of the planning MRI's delineations to the daily anatomy. We therefore investigate the accuracy and time needed for online clinical target volume (CTV) adaptation by radiation therapists (RTT), to be used in MRI-guided adaptive treatments on a MRI-Linac (MRL). Methods: Sixteen patients, diagnosed with early stage rectal cancer, underwent a T2-weighted MRI prior to each fraction of short-course radiotherapy, resulting in 45 scans per patient. On these scans, the CTV was delineated according to guidelines by an experienced radiation oncologist (RO) and considered to be the gold standard. For each patient, the first MRI was considered as the planning MRI and matched on bony anatomy to the 34 daily MRIs. The planning MRI's CTV delineation was rigidly propagated to the daily MRI scans as a proposal for adaptation. Three RTTs in training started the adaptation of the CTV conform guidelines, after a two hour training lecture and a two patient (n=7) training set. To assess the inter-therapist variation, all three RTTs altered delineations of 3 patients (n=12). One RTT altered the CTV delineations (n=53) of the remaining 11 patients. Time needed for adaptation of the CTV to guidelines was registered.As a measure of agreement, the conformity index (CI) was determined between the RTTs' delineations as a group. Dice similarity coefficients were determined between delineations of the RTT and the RO. Results: We found good agreement between RTTs' and RO's delineations (average Dice=0.91, SD=0.03). Furthermore, the inter-observer agreement between the RTTs was high (average CI=0.94, SD=0.02). Adaptation time reduced from 10:33 min (SD= 3:46) to 2:56 min (SD=1:06) between the first and last ten delineations, respectively. Conclusion: Daily CTV adaptation by RTTs, seems a feasible and safe way to introduce daily, online MRI-based plan adaptation for a MRL.

  17. Dose estimates in a loss of lead shielding truck accident.

    SciTech Connect (OSTI)

    Dennis, Matthew L.; Osborn, Douglas M.; Weiner, Ruth F.; Heames, Terence John (Alion Science & Technology Albuquerque, NM)

    2009-08-01T23:59:59.000Z

    The radiological transportation risk & consequence program, RADTRAN, has recently added an updated loss of lead shielding (LOS) model to it most recent version, RADTRAN 6.0. The LOS model was used to determine dose estimates to first-responders during a spent nuclear fuel transportation accident. Results varied according to the following: type of accident scenario, percent of lead slump, distance to shipment, and time spent in the area. This document presents a method of creating dose estimates for first-responders using RADTRAN with potential accident scenarios. This may be of particular interest in the event of high speed accidents or fires involving cask punctures.

  18. Analysis Approach and Data Package for Mayak Public Doses

    SciTech Connect (OSTI)

    Eslinger, Paul W.; Napier, Bruce A.

    2013-09-18T23:59:59.000Z

    Historical activities at facilities producing nuclear materials for weapons released radioactivity into the air and water. Past studies in the United States have evaluated the release, atmospheric transport and environmental accumulation of 131I from the nuclear facilities at Hanford in Washington State and the resulting dose to members of the public (Farris et al. 1994). A multi-year dose reconstruction effort (Mokrov et al. 2004) is also being conducted to produce representative dose estimates for members of the public living near Mayak, Russia, from atmospheric releases of 131I at the facilities of the Mayak Production Association. The approach to calculating individual doses to members of the public from historical releases of airborne 131I has the following general steps: Construct estimates of releases 131I to the air from production facilities. Model the transport of 131I in the air and subsequent deposition on the ground and vegetation. Model the accumulation of 131I in soil, water and food products (environmental media). Calculate the dose for an individual by matching the appropriate lifestyle and consumption data for the individual to the concentrations of 131I in environmental media at their residence location. A number of computer codes were developed to facilitate the study of airborne 131I emissions at Hanford. Of particular interest is DESCARTES code that modeled accumulation of 131I in environmental media (Miley et al. 1994). In addition, the CIDER computer code estimated annual doses to individuals (Eslinger et al. 1994) using the equations and parameters specific to Hanford (Snyder et al. 1994). Several of the computer codes developed to model 131I releases from Hanford are general enough to be used for other facilities. Additional codes have been developed, including the new individual dose code CiderF (Eslinger and Napier 2013), and applied to historical releases of 131I from Mayak. This document provides a data package that identifies computer code runs and associated input and output files prepared for the purpose of calculating doses to members of the public from atmospheric releases of 131I at the Mayak Production Association for the time period 1948 through 1972.

  19. Analysis of highdose rate brachytherapy dose distribution resemblance in CyberKnife hypofractionated treatment plans of localized prostate cancer

    SciTech Connect (OSTI)

    Sudahar, H., E-mail: h.sudahar@gmail.com [Department of Radiotherapy, Apollo Speciality Hospital, Chennai (India); Kurup, P.G.G.; Murali, V.; Mahadev, P. [Department of Radiotherapy, Apollo Speciality Hospital, Chennai (India); Velmurugan, J. [Department of Medical Physics, Anna University, Chennai (India)

    2013-01-01T23:59:59.000Z

    The present study is to analyze the CyberKnife hypofractionated dose distribution of localized prostate cancer in terms of highdose rate (HDR) brachytherapy equivalent doses to assess the degree of HDR brachytherapy resemblance of CyberKnife dose distribution. Thirteen randomly selected localized prostate cancer cases treated using CyberKnife with a dose regimen of 36.25 Gy in 5 fractions were considered. HDR equivalent doses were calculated for 30 Gy in 3 fractions of HDR brachytherapy regimen. The D{sub 5%} of the target in the CyberKnife hypofractionation was 41.57 2.41 Gy. The corresponding HDR fractionation (3 fractions) equivalent dose was 32.81 1.86 Gy. The mean HDR fractionation equivalent dose, D{sub 98%}, was 27.93 0.84 Gy. The V{sub 100%} of the prostate target was 95.57% 3.47%. The V{sub 100%} of the bladder and the rectum were 717.16 and 79.6 mm{sup 3}, respectively. Analysis of the HDR equivalent dose of CyberKnife dose distribution indicates a comparable resemblance to HDR dose distribution in the peripheral target doses (D{sub 98%} to D{sub 80%}) reported in the literature. However, there is a substantial difference observed in the core high-dose regions especially in D{sub 10%} and D{sub 5%}. The dose fall-off within the OAR is also superior in reported HDR dose distribution than the HDR equivalent doses of CyberKnife.

  20. RUMINAL ADAPTATION TO INCREASING LEVELS OF CONCENTRATES

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    .0 % citrus pulp, 1.0 % lard, 7.0 % sugarbeet pulp, 3.3 % oat husk meal, 2.0 % coconut expeller and 2-chromatography. The rate of lactate fermentation was measured by incubation of 10 ml rumen fluid (taken at 14.00 h) with 1. If adaptation occurs one should expect an increase of lactate and a higher rate of L- lactate fermentation