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Note: This page contains sample records for the topic "radiation-induced genomic instability" from the National Library of EnergyBeta (NLEBeta).
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1

Hydrogen peroxide significantly contributes to radiation-induced genomic instability  

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

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

2

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

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

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

3

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

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

4

The Role of Telomere Dysfunction in Driving Genomic Instability  

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

Telomere Dysfunction in Driving Genomic Instability Telomere Dysfunction in Driving Genomic Instability Susan M. Bailey, Eli S. Williams and Robert L. Ullrich The mechanistic role of radiation-induced genomic instability in radiation carcinogenesis is an attractive hypothesis that remains to be rigorously tested. There are few in vivo studies on which to base judgments, but work in our laboratory with mouse models of radiogenic mammary neoplasia provided the first indications that certain inductive forms of genetically predisposed genomic instability may contribute to tumor development. The central goal of this research project is to more firmly establish the mechanistic basis of this radiation-associated genomic instability and, from this, to assess whether such induced instability might play a major role in tumorigenesis at low doses of low LET radiation. In the case of

5

Development of stable lines of transgenic zebrafish (Danio rerio) to investigate genomic instability  

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stable lines of transgenic zebrafish (Danio rerio) to stable lines of transgenic zebrafish (Danio rerio) to investigate genomic instability Lahcen Jaafar 1 , Wendy W. Kuhne 2 , Xiayang Xie 3 , Xuan Zheng 1,4 , Jeffrey S. Mumm 3 , and William S. Dynan 1 1 Institute of Molecular Medicine and Genetics, Georgia Health Sciences University, Georgia 30912, USA, 2 Savannah River National Laboratory, Aiken SC 29808, 3 Department of Cellular Biology and Anatomy, Georgia Health Sciences University, Georgia 30912, USA, 4 Genetic Diagnosis Center, Zhongnan Hospital of Wuhan University, Wuhan, China The goal of our project is to investigate low-dose radiation induced-genomic instability. We describe the development of a whole-vertebrate model bearing a reporter transgene that is designed to indicate the presence of genome instability by somatic homologous

6

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

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

lesions in the progeny of exposed cells for several cell generations following irradiation. It has been hypothesized that genomic instability is a key event in the...

7

Low Dose Radiation Research Program: Genomic Instability and...  

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Genomic Instability and Low Dose Low Dose Rate Radiation. Authors: Lei Huang, Suzanne Grim, William F. Morgan Institutions: University of Maryland. Humans will always receive...

8

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

SciTech Connect

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

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

2006-01-06T23:59:59.000Z

9

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

E-Print Network (OSTI)

, A. Levy, L. Cernjavski, Clastogenic factors in the plasma of Chernobyl accident recovery workers personnel of the Chernobyl reactor, J. Cancer Res. Clin. Oncol. 120 (1994) 558­561. [17] I. Emerit, M, Clastogenic factors in the plasma of children exposed at Chernobyl, Mutat. Res. 373 (1997) 47­54. [18] F

10

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

SciTech Connect

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

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

1996-12-01T23:59:59.000Z

11

Links between persistent DNA damage, genome instability, and aging  

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

Links between persistent DNA damage, genome instability, and aging Links between persistent DNA damage, genome instability, and aging William Dynan Medical College of Georgia Abstract There is considerable overlap between cellular and molecular changes that occur in response to low doses of ionizing radiation and those that occur during aging. Both processes are characterized by accumulation of persistent DNA damage ("wear and tear" on the genome), accumulation of protein and lipid oxidation products, loss of regenerative capacity at the cellular and tissue level, and increased incidence of cancer. These observations support a hypothesis that exposure to low-dose ionizing radiation accelerates normal, aging-related tissue changes. We have investigated this hypothesis using a genetically tractable model organism, the Japanese medaka fish. The medaka is a whole-animal vertebrate

12

Low Dose Radiation Research Program: Induction of Genomic Instability in  

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

Induction of Genomic Instability in vivo by Low Doses of 137Cs y Induction of Genomic Instability in vivo by Low Doses of 137Cs y rays, Authors: K. Rithidech1, E.B. Whorton2, M. Tungjai1, E. Ar-Bab1, S.R. Simon1, M. Tawde3 and C.W. Anderson3. Institutions: 1Pathology Department, Stony Brook University, NY 11794-8691, USA, 2University of Texas Medical Branch at Galveston, TX 77550-1047,3Biology Department, Brookhaven National Laboratory, Upton, NY 11973-5000. Information on potential health hazards of radiation at doses below or equal to the level traditionally requiring human radiation protection (less than or equal to 10 cGy) is currently lacking. It is therefore important to characterize early and subsequent in vivo biological response induced by low doses of ionizing radiation because such data should provide information that can help determine whether radiation at this dose level

13

Radiation-induced angiosarcoma  

E-Print Network (OSTI)

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

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

2013-01-01T23:59:59.000Z

14

KUB5/HERA: a dual acting protein that suppresses genomic instability and promotes DNA repair after low dose IR exposure  

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

KUB5/HERA: a dual acting protein that suppresses genomic instability and KUB5/HERA: a dual acting protein that suppresses genomic instability and promotes DNA repair after low dose IR exposure Julio C. Morales 1 , Amy Rommel 1 , Konstantin Leskov 2 , Walter M. Hittelman 3 , David A. Boothman 1# 1 Simmons Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA. 2 Department of Radiation Oncology, Case Western Reserve University, Cleveland, OH 44106, USA. 3 Department of Experimental Therapeutics, M.D. Anderson Cancer Center, Houston, TX 77030, USA. # To whom correspondence should be addressed. E-mail: David.Boothman@utsouthwestern.edu Eukaryotic cells can respond to DNA double strand breaks created by low doses of IR by activating homologous recombination (HR) or non-homologous end- joining (NHEJ) pathways to repair DNA. A yeast two-hybrid screen using Ku70 as

15

Low Dose Radiation Research Program: Interaction of Genome and Cellular  

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

16

No evidence for in vivo induction of genomic instability in bone marrow cells collected from mice exposed to low-dose 137Cs γ rays:  

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

Rithidech et al, 2006 1 Rithidech et al, 2006 1 No evidence for in vivo induction of genomic instability in bone marrow cells collected from mice exposed to low-dose 137 Cs γ rays: Kanokporn Noy Rithidech 1 , Chatchanok Loetchutinat 1 , Louise Honikel 1 , and Elbert B. Whorton 2 1 Pathology Department, Stony Brook University, Stony Brook, NY 11794-8691 2 Molecular Epidemiology Research Program, University of Texas Medical Branch at Galveston, TX 77555-1153 Assessment of potential health risks associated with exposure to low-dose radiation (at doses below or equal to 0.1 Gy) is still a challenging public health issue. It is therefore important to improve our understanding of potential induction of genomic instability in vivo by this low-dose range because it has been widely suggested that elevation of genomic instability also elevates cancer

17

Radiation-Induced Effects on Microstructure  

Science Conference Proceedings (OSTI)

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

Zinkle, Steven J [ORNL

2012-01-01T23:59:59.000Z

18

Radiation induced corrosion of steel; Strlningsinducerad korrosion av stl.  

E-Print Network (OSTI)

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

Nilsson, Oskar

2011-01-01T23:59:59.000Z

19

Radiation-Induced Bystander Effects and Relevance to Human Radiation  

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

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

20

Delayed Radiation-Induced Vasculitic Leukoencephalopathy  

SciTech Connect

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

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

2012-05-01T23:59:59.000Z

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


21

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

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

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

22

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

SciTech Connect

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

Barry D. Michael; Kathryn Held; Kevin Prise

2002-12-19T23:59:59.000Z

23

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

SciTech Connect

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

Kathy Held; Kevin Prise; Barry Michael; Melvyn Folkard

2002-12-14T23:59:59.000Z

24

Low Dose Radiation Research Program: Frequencies of Radiation-Induced  

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

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

25

Low dose ionizing radiation induces tumor growth promoting factors in  

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

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

26

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

SciTech Connect

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

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

2013-05-01T23:59:59.000Z

27

Measurements of prompt radiation induced conductivity of Kapton.  

SciTech Connect

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

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

2010-10-01T23:59:59.000Z

28

Radiation-induced solitary waves in hot plasmas of accretion disks  

E-Print Network (OSTI)

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

Fedor V. Prigara

2005-07-08T23:59:59.000Z

29

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

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

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

30

Emission of radiation induced by pervading Alfven waves  

SciTech Connect

It is shown that under certain conditions, propagating Alfven waves can energize electrons so that consequently a new cyclotron maser instability is born. The necessary condition is that the plasma frequency is lower than electron gyrofrequency. This condition implies high Alfven speed, which can pitch-angle scatter electrons effectively and therefore the electrons are able to acquire free energy which are needed for the instability.

Zhao, G. Q. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wu, C. S. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China); Institute of Space Science, National Central University, Zhongli, Taiwan (China)

2013-03-15T23:59:59.000Z

31

Radiation-induced leukemia: Comparative studies in mouse and man  

SciTech Connect

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

Haas, M.

1991-01-01T23:59:59.000Z

32

Radiation induced strand breakage analyzed by tunel technique  

E-Print Network (OSTI)

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

Reynolds, Marissa Dawn

2003-01-01T23:59:59.000Z

33

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

Science Conference Proceedings (OSTI)

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

Brannon, P.J.

1993-11-01T23:59:59.000Z

34

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

Science Conference Proceedings (OSTI)

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

Cheryl G. Burrell, Ph.D.

2012-05-14T23:59:59.000Z

35

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

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

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

36

Thermal instability of an expanding dusty plasma with equilibrium cooling  

E-Print Network (OSTI)

We present an analysis of radiation induced instabilities in an expanding plasma with considerable presence of dust particles and equilibrium cooling. We have shown that the equilibrium expansion and cooling destabilize the radiation condensation modes and the presence of dust particles enhances this effect. We have examined our results in the context of ionized, dusty-plasma environments such as those found in planetary nebulae (PNe). We show that due to the non-static equilibrium and finite equilibrium cooling, small-scale localized structures formed out of thermal instability, become transient, which agrees with the observational results. The dust-charge fluctuation is found to heavily suppress these instabilities, though in view of non-availability of convincing experimental data, a definitive conclusion could not be made.

Bora, Madhurjya P

2007-01-01T23:59:59.000Z

37

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

Science Conference Proceedings (OSTI)

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

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

2013-02-01T23:59:59.000Z

38

Radiation-Induced Epigenetic Alterations after Low and High LET Irradiations  

SciTech Connect

Epigenetics, including DNA methylation and microRNA (miRNA) expression, could be the missing link in understanding the delayed, non-targeted effects of radiation including radiationinduced genomic instability (RIGI). This study tests the hypothesis that irradiation induces epigenetic aberrations, which could eventually lead to RIGI, and that the epigenetic aberrations induced by low linear energy transfer (LET) irradiation are different than those induced by high LET irradiations. GM10115 cells were irradiated with low LET x-rays and high LET iron (Fe) ions and evaluated for DNA damage, cell survival and chromosomal instability. The cells were also evaluated for specific locus methylation of nuclear factor-kappa B (NF?B), tumor suppressor in lung cancer 1 (TSLC1) and cadherin 1 (CDH1) gene promoter regions, long interspersed nuclear element 1 (LINE-1) and Alu repeat element methylation, CpG and non-CpG global methylation and miRNA expression levels. Irradiated cells showed increased micronucleus induction and cell killing immediately following exposure, but were chromosomally stable at delayed times post-irradiation. At this same delayed time, alterations in repeat element and global DNA methylation and miRNA expression were observed. Analyses of DNA methylation predominantly showed hypomethylation, however hypermethylation was also observed. MiRNA shown to be altered in expression level after x-ray irradiation are involved in chromatin remodeling and DNA methylation. Different and higher incidence of epigenetic changes were observed after exposure to low LET x-rays than high LET Fe ions even though Fe ions elicited more chromosomal damage and cell killing. This study also shows that the irradiated cells acquire epigenetic changes even though they are chromosomally stable suggesting that epigenetic aberrations may arise in the cell without initiating RIGI.

Aypar, Umut; Morgan, William F.; Baulch, Janet E.

2011-02-01T23:59:59.000Z

39

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

Science Conference Proceedings (OSTI)

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

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

2012-11-01T23:59:59.000Z

40

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

SciTech Connect

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

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

2013-10-01T23:59:59.000Z

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


41

On Moist Instability  

Science Conference Proceedings (OSTI)

An argument is made that the concepts of conditional instability and conditional symmetric instability need to be revisited. Confusion in the profession has led to two extant definitions of conditional instability that are superficially similar ...

Steven C. Sherwood

2000-12-01T23:59:59.000Z

42

Modulating radiation induced TGFβ and ATM signaling in the DNA damage  

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

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

43

LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES  

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

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

44

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

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

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

45

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

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

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

46

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

SciTech Connect

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

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

1987-01-01T23:59:59.000Z

47

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

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

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

48

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

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

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

49

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

E-Print Network (OSTI)

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

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

2011-04-12T23:59:59.000Z

50

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

Science Conference Proceedings (OSTI)

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

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

2005-05-01T23:59:59.000Z

51

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

SciTech Connect

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

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

1986-01-01T23:59:59.000Z

52

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

Science Conference Proceedings (OSTI)

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

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

2012-01-01T23:59:59.000Z

53

MHD Instabilities in Tokamaks  

Science Conference Proceedings (OSTI)

Equilibrium and Instabilities / Proceedings of the Ninth Carolus Magnus Summer School on Plasma and Fusion Energy Physics

H. J. de Blank

54

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

SciTech Connect

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

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

1988-01-01T23:59:59.000Z

55

Transient radiation-induced absorption in materials for the DOI laser  

Science Conference Proceedings (OSTI)

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

Brannon, P.J.

1995-01-01T23:59:59.000Z

56

DNA repair efficiency in germ cells and early mouse embryos and consequences for radiation-induced transgenerational genomic damage  

E-Print Network (OSTI)

mutation rate in the post-chernobyl families from ukraine.mutation rate after the Chernobyl accident. Nature 380, 683-fallout following the Chernobyl accident (Dubrova et al. ,

Marchetti, Francesco

2009-01-01T23:59:59.000Z

57

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

E-Print Network (OSTI)

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

Lennox, A J

2002-01-01T23:59:59.000Z

58

Nonlocal magnetorotational instability  

Science Conference Proceedings (OSTI)

An analytical theory of the nonlocal magnetorotational instability (MRI) is developed for the simplest astrophysical plasma model. It is assumed that the rotation frequency profile has a steplike character, so that there are two regions in which it has constant different values, separated by a narrow transition layer. The surface wave approach is employed to investigate the MRI in this configuration. It is shown that the main regularities of the nonlocal MRI are similar to those of the local instability and that driving the nonaxisymmetric MRI is less effective than the axisymmetric one, also for the case of the nonlocal instability. The existence of nonlocal instabilities in nonmagnetized plasma is predicted.

Mikhailovskii, A. B.; Erokhin, N. N. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); Lominadze, J. G. [Kharadze Abastumani National Astrophysical Observatory, 2a, Kazbegi Ave., Tbilisi 0160 (Georgia); Galvao, R. M. O. [Institute of Physics, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo (Brazil); Brazilian Center for Research in Physics, Rua Xavier Sigaud 150, Rio de Janeiro, BR-22290180 (Brazil); Churikov, A. P. [Syzran Branch of Samara Technical University, 45, Sovetskaya Str., Syzran, Samara Region 446001 (Russian Federation); Kharshiladze, O. A. [Nodia Institute of Geophysics, 1, Aleksidze Str., Tbilisi 0193 (Georgia); Amador, C. H. S. [Brazilian Center for Research in Physics, Rua Xavier Sigaud 150, Rio de Janeiro, BR-22290180 (Brazil)

2008-05-15T23:59:59.000Z

59

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

Science Conference Proceedings (OSTI)

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

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

2012-06-15T23:59:59.000Z

60

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

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

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

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61

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

Science Conference Proceedings (OSTI)

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

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

2010-11-01T23:59:59.000Z

62

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

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

63

The Intricacies of Instabilities  

Science Conference Proceedings (OSTI)

In response to Sherwoods comments and in an attempt to restore proper usage of terminology associated with moist instability, the early history of moist instability is reviewed. This review shows that many of Sherwoods concerns about the ...

David M. Schultz; Philip N. Schumacher; Charles A. Doswell III

2000-12-01T23:59:59.000Z

64

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

DOE Green Energy (OSTI)

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

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

1991-01-01T23:59:59.000Z

65

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

Science Conference Proceedings (OSTI)

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

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

1980-01-01T23:59:59.000Z

66

Topographic Instability: Tests  

Science Conference Proceedings (OSTI)

Theories of topographic instability predict growth of perturbations of mean flow and wave modes due to their interaction with mountains under favorable conditions. Mountain torques form an important part of this interaction. It has been suggested ...

Joseph Egger; Klaus-Peter Hoinka

2008-02-01T23:59:59.000Z

67

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

Science Conference Proceedings (OSTI)

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

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

2009-02-01T23:59:59.000Z

68

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

SciTech Connect

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

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

1982-12-01T23:59:59.000Z

69

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

Science Conference Proceedings (OSTI)

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

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

1995-02-01T23:59:59.000Z

70

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

SciTech Connect

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

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

1993-06-01T23:59:59.000Z

71

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

SciTech Connect

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

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

2009-04-01T23:59:59.000Z

72

ATM Polymorphisms Are Associated With Risk of Radiation-Induced Pneumonitis  

SciTech Connect

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

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

2010-08-01T23:59:59.000Z

73

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

Science Conference Proceedings (OSTI)

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

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

2010-08-01T23:59:59.000Z

74

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

SciTech Connect

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

Kato, H.

1987-01-01T23:59:59.000Z

75

Molluscan Evolutionary Genomics  

E-Print Network (OSTI)

59179 Molluscan Evolutionary Genomics W. Brian Simison andBoore Molluscan Evolutionary Genomics W. Brian Simison andL. Boore Evolutionary Genomics Department, DOE Joint Genome

Simison, W. Brian

2010-01-01T23:59:59.000Z

76

Secondary Instabilities in Langmuir Circulations  

Science Conference Proceedings (OSTI)

Finite-amplitude Langmuir circulation in the form of rolls parallel to the wind direction is shown to be subject to three-dimensional instability under certain circumstances. Density stratification is not required for instability to manifest. The ...

Amit Tandon; Sidney Leibovich

1995-06-01T23:59:59.000Z

77

Dissipation Induced Instabilities  

E-Print Network (OSTI)

The main goal of this paper is to prove that if the energy-momentum (or energy-Casimir) method predicts formal instability of a relative equilibrium in a Hamiltonian system with symmetry, then with the addition of dissipation, the relative equilibrium becomes spectrally and hence linearly and nonlinearly unstable. The energy-momentum method assumes that one is in the context of a mechanical system with a given symmetry group. Our result assumes that the dissipation chosen does not destroy the conservation law associated with the given symmetry group---thus, we consider internal dissipation. This also includes the special case of systems with no symmetry and ordinary equilibria. The theorem is proved by combining the techniques of Chetaev, who proved instability theorems using a special Chetaev-Lyapunov function, with those of Hahn, which enable one to strengthen the Chetaev results from Lyapunov instability to spectral instability. The main achievement is to strengthen Chetaev's methods to the context of the block diagonalization version of the energy momentum method given by Lewis, Marsden, Posbergh, and Simo. However, we also give the eigenvalue movement formulae of Krein, MacKay and others both in general and adapted to the context of the normal form of the linearized equations given by the block diagonal form, as provided by the energy-momentum method. A number of specific examples, such as the rigid body with internal rotors, are provided to illustrate the results.

Anthony Bloch; P. S. Krishnaprasad; Jerrold E. Marsden; Tudor S. Ratiu

1993-04-14T23:59:59.000Z

78

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

SciTech Connect

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

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

2005-04-01T23:59:59.000Z

79

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

SciTech Connect

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

Wang, Daojing; Jang, Deok-Jin

2009-08-21T23:59:59.000Z

80

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

SciTech Connect

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

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

2008-11-10T23:59:59.000Z

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


81

Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in  

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

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

82

Gas turbine combustion instability  

DOE Green Energy (OSTI)

Combustion oscillations are a common problem in development of LPM (lean premix) combustors. Unlike earlier, diffusion style combustors, LPM combustors are especially susceptible to oscillations because acoustic losses are smaller and operation near lean blowoff produces a greater combustion response to disturbances in reactant supply, mixing, etc. In ongoing tests at METC, five instability mechanisms have been identified in subscale and commercial scale nozzle tests. Changes to fuel nozzle geometry showed that it is possible to stabilize combustion by altering the timing of the feedback between acoustic waves and the variation in heat release.

Richards, G.A.; Lee, G.T.

1996-09-01T23:59:59.000Z

83

Molluscan Evolutionary Genomics  

E-Print Network (OSTI)

Todays high-throughput genome sequencing centers lack thecomplete nuclear genome sequencing, with several mollusksparticipation. The cost of genome sequencing is still very

Simison, W. Brian

2010-01-01T23:59:59.000Z

84

JGI Fungal Genomics Program  

E-Print Network (OSTI)

View Supports functional genomics, user data deposition andJGI Fungal Genomics Program Igor V. Grigoriev 1 DOE Jointof California. JGI Fungal Genomics Program Contact: Igor

Grigoriev, Igor V.

2011-01-01T23:59:59.000Z

85

JGI Fungal Genomics Program  

E-Print Network (OSTI)

JGI Fungal Genomics Program Igor V. Grigoriev 1 Lawrenceof California. JGI Fungal Genomics Program Contact: IgorJGI). Its key project, the Genomics Encyclopedia of Fungi,

Grigoriev, Igor V.

2012-01-01T23:59:59.000Z

86

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

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

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

87

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

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

genetic backgrounds (BALBcJ and C57BL6J mice) collected at different times post-irradiation (i.e. 1 hr, 4 hrs, 1 month and 6 months). A total of five mice per dose per strain...

88

Low Dose Radiation Research Program: Delayed Genomic Instability...  

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

Lymphoblasts Exposed to 137Cs y-rays Radiation Authors: Jeffrey L. Schwartzb, Robert Jordan,b, Marek Lenarczyk,a and Howard L. Libera Institutions: a Department of Environmental...

89

Breast tumor copy number aberration phenotypes and genomic instability  

E-Print Network (OSTI)

Ziegler 2 , Koei Chin 2,6 , Sandy Devries 2,6 , Heidi Feilerkchin@cc.ucsf.edu; Sandy Devries - devries@cc.ucsf.edu;

2006-01-01T23:59:59.000Z

90

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

SciTech Connect

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

Haas, M.

1991-12-31T23:59:59.000Z

91

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

SciTech Connect

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

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

2010-07-15T23:59:59.000Z

92

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

Science Conference Proceedings (OSTI)

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

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

1995-07-15T23:59:59.000Z

93

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

Science Conference Proceedings (OSTI)

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

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

2012-11-15T23:59:59.000Z

94

Charney's Problem for Baroclinic Instability Applied to Barotropic Instability  

Science Conference Proceedings (OSTI)

It is suggested that barotropically unstable easterly jets may be approximated by broken line profiles. It is then possible to use solutions to the Charney problem for baroclinic instability in order to solve the barotropic problem. Results are ...

R. S. Lindzen; A. J. Rosenthal; B. Farrell

1983-04-01T23:59:59.000Z

95

Baroclinic Instability with Cumulus Heating  

Science Conference Proceedings (OSTI)

We have investigated baroclinic instability with cumulus heating using a vertically discrete, linearized, quasi-geostrophic model on a ?-plane. Two formulations of cumulus heating were used. The first formulation (?-model) rests on the assumption ...

Shrinivas Moorthi; Akio Arakawa

1985-10-01T23:59:59.000Z

96

Mixed Layer Instabilities and Restratification  

Science Conference Proceedings (OSTI)

The restratification of the oceanic surface mixed layer that results from lateral gradients in the surface density field is studied. The lateral gradients are shown to be unstable to ageostrophic baroclinic instabilities and slump from the ...

Giulio Boccaletti; Raffaele Ferrari; Baylor Fox-Kemper

2007-09-01T23:59:59.000Z

97

Resistive instabilities in a tokamak  

SciTech Connect

Application of resistive instability theory shows that toroidal effects can stabilize the tearing mode in devices like the Princeton Large Torus. Contraction of the current channel is destabilizing. Finite fluid compressibility is crucial to this phenomenon. (auth)

Glasser, A.H.; Greene, J.M.; Johnson, J.L.

1975-10-01T23:59:59.000Z

98

Using Partial Genomic Fosmid Libraries for Sequencing Complete Organellar Genomes  

E-Print Network (OSTI)

than total nuclear genome sequencing, making broaderavailable organellar genome sequencing methods, especiallyenables plastid genome sequencing from both parasitic and

McNeal, Joel R.; Leebens-Mack, James H.; Arumuganathan, K.; Kuehl, Jennifer V.; Boore, Jeffrey L.; dePamphilis, Claude W.

2005-01-01T23:59:59.000Z

99

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

DOE Green Energy (OSTI)

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

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

1980-01-01T23:59:59.000Z

100

The Nature of Symmetric Instability and Its Similarity to Convective and Inertial Instability  

Science Conference Proceedings (OSTI)

It is shown that there exists a local similarity among SI (symmetric instability), BI (buoyancy or convective instability), and II (inertial instability) even for fully nonlinear viscous motion. The most unstable slope angles for SI are analyzed ...

Qin Xui; J. H. E. Clark

1985-12-01T23:59:59.000Z

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101

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

Science Conference Proceedings (OSTI)

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

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

2013-02-01T23:59:59.000Z

102

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

Science Conference Proceedings (OSTI)

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

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

1989-07-01T23:59:59.000Z

103

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

SciTech Connect

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

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

2009-12-01T23:59:59.000Z

104

Stellar explosions, instabilities, and turbulence  

Science Conference Proceedings (OSTI)

It has become very clear that the evolution of structure during supernovae is centrally dependent on the pre-existing structure in the star. Modeling of the pre-existing structure has advanced significantly, leading to improved understanding and to a physically based assessment of the structure that will be present when a star explodes. It remains an open question whether low-mode asymmetries in the explosion process can produce the observed effects or whether the explosion mechanism somehow produces jets of material. In any event, the workhorse processes that produce structure in an exploding star are blast-wave driven instabilities. Laboratory experiments have explored these blast-wave-driven instabilities and specifically their dependence on initial conditions. Theoretical work has shown that the relative importance of Richtmyer-Meshkov and Rayleigh-Taylor instabilities varies with the initial conditions and does so in ways that can make sense of a range of astrophysical observations.

Drake, R. P.; Kuranz, C. C. [University of Michigan, 2455 Hayward St., Ann Arbor, Michigan 48109 (United States); Miles, A. R. [Lawrence Livermore National Laboratory, 7500 East Ave., Livermore, California 94550 (United States); Muthsam, H. J. [Faculty of Mathematics, University of Vienna, Nordbergstr. 15, A-1090 Vienna (Austria); Plewa, T. [School of Computational Science, Florida State University, DSL 443, Tallahassee, Florida 32306 (United States)

2009-04-15T23:59:59.000Z

105

Genomics and Systems Biology  

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

Genomics and Systems Biology LANL leads the world in computational finishing of microbial genomes Read caption + In 2013, Los Alamos scientist Richard Sayre and his team...

106

Does Ekman Friction Suppress Baroclinic Instability?  

Science Conference Proceedings (OSTI)

The effect of Ekman friction on baroclinic instability is reexamined in order to address questions raised by Farrell concerning the existence of normal mode instability in the atmosphere. As the degree of meridional confinement is central to the ...

Shian-Jiann Lin; Raymond T. Pierrehumbert

1988-10-01T23:59:59.000Z

107

Vortex driven flame dynamics and combustion instability  

E-Print Network (OSTI)

Combustion instability in premixed combustors mostly arises due to the coupling between heat release rate dynamics and system acoustics. It is crucial to understand the instability mechanisms to design reliable, high ...

Altay, Hurrem Murat

2005-01-01T23:59:59.000Z

108

INSTABILITY OF CERTAIN ELECTROHYDRODYNAMIC SYSTEMS  

SciTech Connect

The production of ion drag pressure under dynamic conditions, i.e., with the carrier medium in motion, is theoretically investigated. It is shown thai for constant applied voltage the pressure increases with increasing velocity of the carrier fluid. This can lead to instability of the system which is theoretically discussed and experimentally demonstrated. (auth)

Stuetzer, O.M.

1959-11-01T23:59:59.000Z

109

Ion temperature gradient instability and anomalous transport  

SciTech Connect

This report discusses experiments in ion temperature gradient instability and anomalous transport in the CLM steady state device. (LSP).

Sen, A.K.

1991-08-01T23:59:59.000Z

110

Microwave instabilities in Booster and AGS  

SciTech Connect

Microwave instabilities is evaluated for the Booster and AGS for the preparation of the relativistic heavy ion collider. We found that the Booster may require feedback system for the transverse instability at the high intensity proton operation. The coherent instability is not important for the nominal RhIC operational intensity.

Lee, S.Y.; Zhao, X.F.

1987-03-13T23:59:59.000Z

111

Dynamical instability of collapsing radiating fluid  

SciTech Connect

We take the collapsing radiative fluid to investigate the dynamical instability with cylindrical symmetry. We match the interior and exterior cylindrical geometries. Dynamical instability is explored at radiative and non-radiative perturbations. We conclude that the dynamical instability of the collapsing cylinder depends on the critical value {gamma} < 1 for both radiative and nonradiative perturbations.

Sharif, M., E-mail: msharif.math@pu.edu.pk; Azam, M., E-mail: azammath@gmail.com [University of the Punjab, Department of Mathematics (Pakistan)

2013-06-15T23:59:59.000Z

112

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

SciTech Connect

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

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

2012-11-01T23:59:59.000Z

113

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

Science Conference Proceedings (OSTI)

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

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

2013-02-01T23:59:59.000Z

114

JGI Fungal Genomics Program  

SciTech Connect

Genomes of energy and environment fungi are in focus of the Fungal Genomic Program at the US Department of Energy Joint Genome Institute (JGI). Its key project, the Genomics Encyclopedia of Fungi, targets fungi related to plant health (symbionts, pathogens, and biocontrol agents) and biorefinery processes (cellulose degradation, sugar fermentation, industrial hosts), and explores fungal diversity by means of genome sequencing and analysis. Over 50 fungal genomes have been sequenced by JGI to date and released through MycoCosm (www.jgi.doe.gov/fungi), a fungal web-portal, which integrates sequence and functional data with genome analysis tools for user community. Sequence analysis supported by functional genomics leads to developing parts list for complex systems ranging from ecosystems of biofuel crops to biorefineries. Recent examples of such 'parts' suggested by comparative genomics and functional analysis in these areas are presented here

Grigoriev, Igor V.

2011-03-14T23:59:59.000Z

115

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

Science Conference Proceedings (OSTI)

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

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

1995-07-15T23:59:59.000Z

116

Climate Instability and Public Health  

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

Climate Instability and Public Health Climate Instability and Public Health Speaker(s): Paul Epstein Date: August 7, 2003 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Evan Mills Climate restricts the range of infectious diseases, while weather affects the timing and intensity of outbreaks. The ranges of several key diseases or their vectors are changing, along with shifts in plant communities and the retreat of alpine glaciers. In addition, extreme weather events associated with warming create conditions conducive to "clusters" of disease outbreaks. The rapid spread of West Nile virus in the Americas is related, paradoxically, to drought and its impact on wildlife (230 species of animals, 138 species of birds) could alter the ratios of predator birds to their prey (including rodents) and thus have implications for human

117

Combustion instability modeling and analysis  

DOE Green Energy (OSTI)

It is well known that the two key elements for achieving low emissions and high performance in a gas turbine combustor are to simultaneously establish (1) a lean combustion zone for maintaining low NO{sub x} emissions and (2) rapid mixing for good ignition and flame stability. However, these requirements, when coupled with the short combustor lengths used to limit the residence time for NO formation typical of advanced gas turbine combustors, can lead to problems regarding unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions, as well as the occurrence of combustion instabilities. The concurrent development of suitable analytical and numerical models that are validated with experimental studies is important for achieving this objective. A major benefit of the present research will be to provide for the first time an experimentally verified model of emissions and performance of gas turbine combustors. The present study represents a coordinated effort between industry, government and academia to investigate gas turbine combustion dynamics. Specific study areas include development of advanced diagnostics, definition of controlling phenomena, advancement of analytical and numerical modeling capabilities, and assessment of the current status of our ability to apply these tools to practical gas turbine combustors. The present work involves four tasks which address, respectively, (1) the development of a fiber-optic probe for fuel-air ratio measurements, (2) the study of combustion instability using laser-based diagnostics in a high pressure, high temperature flow reactor, (3) the development of analytical and numerical modeling capabilities for describing combustion instability which will be validated against experimental data, and (4) the preparation of a literature survey and establishment of a data base on practical experience with combustion instability.

Santoro, R.J.; Yang, V.; Santavicca, D.A. [Pennsylvania State Univ., University Park, PA (United States); Sheppard, E.J. [Tuskeggee Univ., Tuskegee, AL (United States). Dept. of Aerospace Engineering

1995-12-31T23:59:59.000Z

118

Dynamics of instabilities and intermittency  

SciTech Connect

We study the behavior of a finite classical system in the instability region. The equation of state of such a system resembles that of nuclear matter. Through a study of mass distributions, scaled factorial moments, and anomalous fractal dimensions, we provide evidence of the presence of critical behavior of our system. Such behavior can be understood by use of the droplet model of the liquid-gas phase transition.

Latora, V.; Belkacem, M.; Bonasera, A. (Istituto Nazionale di Fisica Nucleare-Laboratorio Nazionale del Sud, Viale Andrea Doria (ang. Via. S. Sofia), 95129 Catania (Italy))

1994-09-26T23:59:59.000Z

119

CGAL: computing genome assembly likelihoods  

E-Print Network (OSTI)

SM, Lei M, Li J, et al: Genome sequencing in microfabricatedDe novo bacterial genome sequencing: millions of very shortGenome assembly, evaluation, likelihood, sequencing.

Rahman, Atif; Pachter, Lior

2013-01-01T23:59:59.000Z

120

Genomics and the human genome project: implications for psychiatry  

E-Print Network (OSTI)

and psychosis: a convergent functional genomics approach.Physiology & Genomics, 4, 8391. O LIPHANT , A. , B ARKER ,2004), 16(4), 294300 Genomics and the Human Genome Project:

Kelsoe, J R

2004-01-01T23:59:59.000Z

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


121

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

Science Conference Proceedings (OSTI)

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

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

2011-04-01T23:59:59.000Z

122

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

SciTech Connect

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

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

2012-07-19T23:59:59.000Z

123

Comparative genomic workflow  

E-Print Network (OSTI)

his article describes a workflow for identifying conserved patterns in noncoding regions of vertebrate genomes, with an intention of investigating possible functions of the conserved regions. The annotations of genomes are ...

Rajapakse, Jagath

124

Genome in a Bottle Consortium  

Science Conference Proceedings (OSTI)

Genome in a Bottle Consortium. Summary: NIST has organized the "Genome in a Bottle Consortium" to develop the reference ...

2013-03-15T23:59:59.000Z

125

Coherent instabilities in random lasers  

SciTech Connect

A numerical study is presented of random lasers as a function of the pumping rate above the threshold for lasing. Depending on the leakiness of the system resonances, which is typically larger in random lasers compared to conventional lasers, we observe that the stationary lasing regime becomes unstable above a second threshold. Coherent instabilities are observed as self pulsation at a single frequency of the output intensity, population inversion, as well as the atomic polarization. We find these Rabi oscillations have the same frequency everywhere in the random laser despite the fact that the field intensity strongly depends on the spatial location.

Andreasen, Jonathan; Sebbah, Patrick; Vanneste, Christian [Laboratoire de Physique de la Matiere Condensee, CNRS UMR 6622, Universite de Nice-Sophia Antipolis, Parc Valrose, F-06108, Nice Cedex 02 (France)

2011-08-15T23:59:59.000Z

126

Hydromagnetic Instability in plane Couette Flow  

E-Print Network (OSTI)

We study the stability of a compressible magnetic plane Couette flow and show that compressibility profoundly alters the stability properties if the magnetic field has a component perpendicular to the direction of flow. The necessary condition of a newly found instability can be satisfied in a wide variety of flows in laboratory and astrophysical conditions. The instability can operate even in a very strong magnetic field which entirely suppresses other MHD instabilities. The growth time of this instability can be rather short and reach $\\sim 10$ shear timescales.

Bonanno, Alfio

2007-01-01T23:59:59.000Z

127

Higgs instability in gapless superfluidity/superconductivity  

E-Print Network (OSTI)

In this letter we explore the Higgs instability in the gapless superfluid/superconducting phase. This is in addition to the (chromo)magnetic instability that is related to the fluctuations of the Nambu-Goldstone bosonic fields. While the latter may induce a single-plane-wave LOFF state, the Higgs instability favors spatial inhomogeneity and cannot be removed without a long range force. In the case of the g2SC state the Higgs instability can only be partially removed by the electric Coulomb energy. But this does not exclude the possibility that it can be completely removed in other exotic states such as the gCFL state.

Ioannis Giannakis; Defu Hou; Mei Huang; Hai-cang Ren

2006-06-16T23:59:59.000Z

128

Diffusion instability in a thermonuclear burn  

SciTech Connect

Time-dependent, one-dimesional equations are solved to demonstrate the possibility of a superheating-diffusion instability in a steady-state fusion reactor.

Vasil' ev, N.N.; Lukash, V.E.; Nedospasov, A.V.

1979-04-01T23:59:59.000Z

129

Negative Bias Temperature Instability in CMOS Devices  

Science Conference Proceedings (OSTI)

This paper reviews the experimental and modeling efforts to understand the mechanism of Negative Bias Temperature Instability (NBTI) in p-MOSFETs, which is becoming a serious reliability concern for analog and digital CMOS circuits. Conditions for interface ... Keywords: MOSFET, NBTI, Reaction-Diffusion model, bulk traps, hydrogen diffusion, interface traps, parameter instability

S. Mahapatra; M. A. Alam; P. Bharath Kumar; T. R. Dalei; D. Varghese; D. Saha

2005-06-01T23:59:59.000Z

130

Modulation instability in RF MEMS devices  

Science Conference Proceedings (OSTI)

Modulation instability generated by mechanical frequencies in RF MEMS switches is predicted and its potential contribution to the RF signal degradation is discussed. In particular, evaluations have been performed for double clamped configurations in ... Keywords: Modulation instability, Nonlinear Schrodinger equation, Power handling, RF MEMS

Romolo Marcelli; Giancarlo Bartolucci; Giorgio Angelis; Andrea Lucibello; Emanuela Proietti

2012-04-01T23:59:59.000Z

131

Magnetic instabilities in accelerating plasma surfaces  

SciTech Connect

The existence of an interchange instability strictly associated with electron inertia is demonstrated. This is characterized by a growth rate significantly larger than the usual ion-inertial Rayleigh-Taylor rate and by self-generated magnetic fields localized around the accelerating plasma surface. This novel instability may be partially responsible for the observed magnetic fields in ablatively accelerated laser plasmas.

Amendt, P.; Rahman, H.U.; Strauss, M.

1984-09-24T23:59:59.000Z

132

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

SciTech Connect

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

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

2012-10-01T23:59:59.000Z

133

Nonlinear Dynamics of Single Bunch Instability  

SciTech Connect

A nonlinear equation is derived that governs the evolution of the amplitude of unstable oscillations with account of quantum diffusion effects due to the synchrotron radiation. Numerical solutions to this equation predict a variety of possible scenarios of nonlinear evolution of the instability some of which are in good qualitative agreement with experimental observations. Microwave single bunch instability in circular accelerators has been observed in many machines. The instability usually arises when the number of particles in the bunch exceeds some critical value, Nc, which varies depending on the parameters of the accelerating regime. Recent observations on the SLC damping rings at SLAC with a new low-impedance vacuum chamber revealed new interesting features of the instability. In some cases, after initial exponential growth, the instability eventually saturated at a level that remained constant through the accumulation cycle. In other regimes, relaxation-type oscillations were measured in nonlinear phase of the instability. In many cases, the instability was characterized by a frequency close to the second harmonic of the synchrotron oscillations. Several attempts have been made to address the nonlinear stage of the instability based on either computer simulations or some specific assumptions regarding the structure of the unstable mode. An attempt of a more general consideration of the problem is carried out in this paper. We adopt an approach recently developed in plasma physics for analysis of nonlinear behavior of weakly unstable modes in dynamic systems. Assuming that the growth rate of the instability is much smaller than its frequency, we find a time dependent solution to Vlasov equation and derive an equation for the complex amplitude of the oscillations valid in the nonlinear regime. Numerical solutions to this equation predict a variety of possible scenarios of nonlinear evolution of the instability some of which are in good qualitative agreement with experimental observations.

Stupakov, G.V.; /SLAC; Breizman, B.N.; Pekker, M.S.; /Texas U.

2011-09-09T23:59:59.000Z

134

Taylor Instability of Incompressible Liquids  

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

\ UNCLASSIFIED ' ;c ,. ' UNCLASSIFIED AECU-29'79 Subject Category: PHYSICS UNITED STATES ATOMIC ENERGY COMMISSION TAYLOR INSTABILITY OF INCOMPRESSIBLE LIQUIDS BY Enrico Fermi John von Neumann , _ November 1955 [ TIS Issuance D.a&?] Los Alamos Scientific Labqratqry Los Alamos, New Mexico Technical Information Service, Ooic Ridge, Tennessee DISCLAIMER Portions of this document may be illegible in electronic image products. Images are produced from the best available document. original I , The date for Part 1 is September 4, 1951. The date for Part 2 is August 19, 1953. Work performed under Contract PTo. W-7405-Eng-36. The Atomic Energy Commission makes no representation or warranty as to the accuracy or usefulness of the lnformatlon or statements contained

135

An integrative approach for genomic island prediction in Prokaryotic genomes  

Science Conference Proceedings (OSTI)

A genomic island (GI) is a segment of genomic sequence that is horizontally transferred from other genomes. The detection of genomic islands is extremely important to the medical research. Most of current computational approaches that use sequence composition ... Keywords: gene information, genomic islands, intergenic distance, sequence composition

Han Wang; John Fazekas; Matthew Booth; Qi Liu; Dongsheng Che

2011-05-01T23:59:59.000Z

136

BMC Genomics BioMed Central  

E-Print Network (OSTI)

Software Genome Annotation Transfer Utility (GATU): rapid annotation of viral genomes using a closely related reference genome

Vasily Tcherepanov; Angelika Ehlers; Chris Upton

2006-01-01T23:59:59.000Z

137

Genomics and Systems Biology  

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

Genomics and Systems Biology Genomics and Systems Biology Genomics and Systems Biology Los Alamos scientists perform research in functional genomics and structural genomics, and applications for such work cover diverse fields such as energy, agriculture, and environmental cleanup. Get Expertise Babetta Marrone Biofuels Program Manager Email Cheryl Kuske DOE BER Biological System Science Division Program Manager Email Chris Detter Emerging Threats Program Manager: Email Rebecca McDonald Bioscience Communications Email "We were asked to build a rocket ship," said developer Joel Berendzen, "but instead we built a 10,000 mph motorcycle." - Sequedex team LANL leads the world in computational finishing of microbial genomes Protein research Read caption + In 2013, Los Alamos scientist Richard Sayre and his team genetically

138

Linear Gain for the Microbunching Instability in an RF Compressor  

E-Print Network (OSTI)

Instability in an RF Compressor M. Venturini Lawrencefor investigating this instability in rf compressors. We useapplied to magnetic compressors [2, 3] and derive some

Venturini, M.

2010-01-01T23:59:59.000Z

139

Genome Sequence Databases (Overview): Sequencing and Assembly  

E-Print Network (OSTI)

complete microbial genome sequencing (you get what you payet al. (2005). Genome sequencing in open microfabricatedof problem solving in genome sequencing. Genome Research 8,

Lapidus, Alla L.

2009-01-01T23:59:59.000Z

140

Genome Analysis and Systems Modeling Group  

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

(Microbial Genomes) Pipeline, Comprehensive Genome Analysis Pipeline Genome Channel, Java applet for the comprehensive sequence-based view of genomes. Grail, a tool for the...

Note: This page contains sample records for the topic "radiation-induced genomic instability" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


141

JGI - Undergraduate Research in Functional Genomics  

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

Education Microbial Genome Analysis Microbial Functional Genomics Undergraduate Research in Microbial Functional Genomics Genomics not only can answer questions about known genes,...

142

Genome Science/Technologies  

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

Science & Innovation » Science & Innovation » Science & Engineering Capabilities » Bioscience: Bioenergy, Biosecurity, and Health » Environmental Microbiology » Genome Genome Science/Technologies Los Alamos using cutting-edge sequencing, finishing, and analysis, impact valuable genomic data. Get Expertise Cheryl Kuske DOE BER Biological System Science Division Program Manager Email Srinivas Iyer Bioscience Group Leader Email Momchilo Vuyisich Bioenergy and Biomedical Sciences Email Rebecca McDonald Bioscience Communications Email State-of-the art technology and extensive genomics expertise Protein research Read caption + Los Alamos National Laboratory graduate student, Patricia Langan, changes the properties of a green fluorescent protein in order to create new fluorescent protein variants.

143

Genome Science/Technologies  

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

Momchilo Vuyisich Bioenergy and Biomedical Sciences Email Rebecca McDonald Bioscience Communications Email State-of-the art technology and extensive genomics expertise Protein...

144

JGI - Genomic Technologies  

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

opportunities for technological access to our user services (including single cell genomics and DNA synthesis). Our Department serves at the interface between the Project...

145

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

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

146

Oscillatory instability in a driven granular gas  

E-Print Network (OSTI)

We discovered an oscillatory instability in a system of inelastically colliding hard spheres, driven by two opposite "thermal" walls at zero gravity. The instability, predicted by a linear stability analysis of the equations of granular hydrodynamics, occurs when the inelasticity of particle collisions exceeds a critical value. Molecular dynamic simulations support the theory and show a stripe-shaped cluster moving back and forth in the middle of the box away from the driving walls. The oscillations are irregular but have a single dominating frequency that is close to the frequency at the instability onset, predicted from hydrodynamics.

Evgeniy Khain; Baruch Meerson

2003-11-13T23:59:59.000Z

147

Centrifugally driven electrostatic instability in extragalactic jets  

SciTech Connect

The stability problem of the rotation-induced electrostatic wave in extragalactic jets is presented. Solving a set of equations describing dynamics of a relativistic plasma flow of active galactic nuclei (AGN) jets, an expression of the instability rate has been derived and analyzed for typical values of AGNs. The growth rate was studied versus the wavelength and the inclination angle and it has been found that the instability process is very efficient with respect to the accretion disk evolution, indicating high efficiency of the instability.

Osmanov, Z. [Georgian National Astrophysical Observatory, Kazbegi ave. 2a, Tbilisi 0160 (Georgia)

2008-03-15T23:59:59.000Z

148

Genomic analysis of mouse tumorigenesis  

E-Print Network (OSTI)

The availability of the human and mouse genome sequences has spurred a growing interest in analyzing mouse models of human cancer using genomic techniques. Comparative genomic studies on mouse and human tumors can be ...

Tam, Mandy Chi-Mun

2006-01-01T23:59:59.000Z

149

Enhancer Identification through Comparative Genomics  

E-Print Network (OSTI)

through Comparative Genomics Axel Visel, James Bristow andWalnut Creek, CA 94598 USA. Genomics Division, MS 84-171,Len A. Pennacchio, Genomics Division, One Cyclotron Road, MS

Visel, Axel; Bristow, James; Pennacchio, Len A.

2006-01-01T23:59:59.000Z

150

Communicating Genomics:GTL  

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

Annual Annual DOE Joint Genome Institute User Meeting Sponsored By U.S. Department of Energy Office of Science March 29-April 1, 2006 Embassy Suites Hotel and DOE Joint Genome Institute Walnut Creek, California iii Contents Agenda .................................................................................................................. iv Speaker Presentations . .........................................................................................1 Abtracts in order of presentation according to agenda (p. iv) Poster Presentations ..............................................................................................9 Posters alphabetical by first author. *Presenting author. Attendees...............................................................................................................75

151

Spectrogram analysis of genomes  

Science Conference Proceedings (OSTI)

We perform frequency-domain analysis in the genomes of various organisms using tricolor spectrograms, identifying several types of distinct visual patterns characterizing specific DNA regions. We relate patterns and their frequency characteristics to ... Keywords: DNA spectrograms, frequency-domain analysis, genome analysis

David Sussillo; Anshul Kundaje; Dimitris Anastassiou

2004-01-01T23:59:59.000Z

152

Legume Crop Genomics  

Science Conference Proceedings (OSTI)

This book will present this technical theme in a manner that should help many readers answer the question, "What is genomics?" And finally, this book should help readers formulate an opinion on the question, "Why is genomic research needed?" Legume Crop Ge

153

Genome Properties Database  

DOE Data Explorer (OSTI)

The Genome Properties system consists of a suite of "Properties" which are carefully defined attributes of prokaryotic organisms whose status can be described by numerical values or controlled vocabulary terms for individual completely sequenced genomes. Evaluation of these properties may take place via manual curation or by computer algorithms (numerical calculations or rules-based assignment of controlled vocabulary terms). The Genome Properties system has been designed to capture the widest possible range of attributes and currently encompasses taxonomic terms, genometric calculations, metabolic pathways, systems of interacting macromolecular components and quantitative and descriptive experimental observations (phenotypes) from the literature. Wherever possible, Genome Properties are linked to traceable lines of evidence and links are provided to data for any genes which are part of this evidence. The primary source of evidence linking genes to properties is homology modelling using Hidden Markov Models (HMMs) from the TIGRFAMs and Pfam databases. (Taken from the Genome Properties Home Page)(Specialized Interface)

Haft, Daniel H.; Selengut, Jeremy D.; Brinkac, Lauren M.; Zafar, Nikhat; White, Owen

154

Capillary instability on a hydrophilic stripe  

E-Print Network (OSTI)

A recent experiment showed that cylindrical segments of water filling a hydrophilic stripe on an otherwise hydrophobic surface display a capillary instability when their volume is increased beyond the critical volume at ...

Speth, Raymond L.

155

Potential Vorticity Dynamics of Tropical Instability Vortices  

Science Conference Proceedings (OSTI)

Tropical instability vortices (TIVs) in the equatorial Pacific exhibit energetic horizontal and vertical circulation characterized by regions of high Rossby number and low Richardson number. Their strong anticyclonic vorticity and vertical shear ...

Ryan M. Holmes; Leif N. Thomas; LuAnne Thompson; David Darr

156

Instabilities in particle-laden flows  

E-Print Network (OSTI)

Particles are present in many industrial processes and in nature. Dry granular flows and suspensions have been well studied and present a broad range of problems in terms of rheology and instabilities. In both cases, new ...

Dupuy, Benjamin, 1981-

2004-01-01T23:59:59.000Z

157

Growth Rates of a Topographic Instability  

Science Conference Proceedings (OSTI)

We consider a linear model of a topographically induced shear instability, described by Pedlosky (1980). The perturbation technique used by Pedlosky, to establish the existence of unstable normal modes, is extended to demonstrate that more than ...

Stephen P. Meacham

1983-09-01T23:59:59.000Z

158

Instability Waves in the Equatorial Atlantic Ocean  

Science Conference Proceedings (OSTI)

Evidence is presented for the generation of planetary waves by barotropic instability within the cyclonic shear region of the Atlantic Ocean's South Equatorial Current (SEC). Immediately following the springtime intensification of the southeast ...

Robert H. Weisberg; Thomas J. Weingartner

1988-11-01T23:59:59.000Z

159

Experimental Study of Wellbore Instability in Clays  

E-Print Network (OSTI)

This paper presents the results of an extensive program of laboratory model wellbore tests that have been performed to study wellbore instability in saturated clays. The tests were conducted on resedimented Boston blue ...

Abdulhadi, Naeem O.

160

Barotropic Instability and Rossby Wave Radiation  

Science Conference Proceedings (OSTI)

A detailed study of linear barotropic instability confirms that the concept of critical level overreflection is fundamental to the understanding of the entire family of unstable modes in this problem. This is in agreement with the general ...

I. Halevy; W. R. Peltier

1985-09-01T23:59:59.000Z

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


161

Linear Baroclinic Instability in the Martian Atmosphere  

Science Conference Proceedings (OSTI)

The linear baroclinic instability of zonal-mean flows like those in the wintertime Martian atmosphere under both relatively nondusty and highly dusty conditions is examined using a spherical quasi-geostrophic model. The basic states are idealized,...

Jeffrey R. Barnes

1984-05-01T23:59:59.000Z

162

Temperature Advection by Tropical Instability Waves  

Science Conference Proceedings (OSTI)

A numerical model of the tropical Pacific Ocean is used to investigate the processes that cause the horizontal temperature advection of tropical instability waves (TIWs). It is found that their temperature advection cannot be explained by the ...

Markus Jochum; Raghu Murtugudde

2006-04-01T23:59:59.000Z

163

Analyzing genomic data: understanding the genome  

Science Conference Proceedings (OSTI)

The effort that led to the sequencing of the human genome ushered life sciences into a new era. One of the largest international scientific endeavors of the time delivered the genetic makeup of our species to the research community. Further international ... Keywords: Algorithmic Development, Biological Data Mining, Data Mining Software Tools

Xos M. Fernndez-Surez

2012-03-01T23:59:59.000Z

164

Jeans instability in a quantum dusty magnetoplasma  

SciTech Connect

Jeans instability in a homogeneous cold quantum dusty plasma in the presence of the ambient magnetic field and the quantum effect arising through the Bohm potential has been examined using the quantum magnetohydrodynamic model. It is found that the Jeans instability is significantly reduced by the presence of the dust-lower-hybrid wave and the ion quantum effect. The minimum wavenumber for Jeans stability depends clearly on ion quantum effect and the dust-lower-hybrid frequency also.

Salimullah, M. [Department of Physics, GC University, Lahore-54000 (Pakistan); Salam Chair in Physics, GC University, Lahore-54000 (Pakistan); Jamil, M.; Shah, H. A. [Department of Physics, GC University, Lahore-54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, GC University, Lahore-54000 (Pakistan)

2009-01-15T23:59:59.000Z

165

Stripe Instabilities of Geometries with Hyperscaling Violation  

E-Print Network (OSTI)

We study the dynamical stripe instabilities on the geometries with hyperscaling violation in the IR, which asymptotically approach AdS_4 in the UV. The instabilities break the translational invariance spontaneously and are induced by the axion term ~ a F \\wedge F in the bulk action. We first study the perturbation equations in the probe limit, and find that there is a strong correlation between the stripe instabilities caused by the axion term and parameters of the theories which determine the IR hyperscaling violation. Contrary to the IR AdS_2 case, the effect of the axion term for the stripe instabilities can be enhanced/suppressed at low temperature depending on the parameters. For a certain one-parameter family of the hyperscaling violation, we find the onset of the stripe instability analytically in the axion coupling tuned model. For more generic parameter range of hyperscaling violation, we study the instability onset by searching for the zero mode numerically on the full geometries. We also argue that quite analogous results hold, after taking into account the graviton fluctuation, i.e., beyond the probe limit.

Norihiro Iizuka; Kengo Maeda

2013-01-24T23:59:59.000Z

166

Energy Gradient Theory of Hydrodynamic Instability  

E-Print Network (OSTI)

A new universal theory for flow instability and turbulent transition is proposed in this study. Flow instability and turbulence transition have been challenging subjects for fluid dynamics for a century. The critical condition of turbulent transition from theory and experiments differs largely from each other for Poiseuille flows. In this paper, a new mechanism of flow instability and turbulence transition is presented for parallel shear flows and the energy gradient theory of hydrodynamic instability is proposed. It is stated that the total energy gradient in the transverse direction and that in the streamwise direction of the main flow dominate the disturbance amplification or decay. A new dimensionless parameter K for characterizing flow instability is proposed for wall bounded shear flows, which is expressed as the ratio of the energy gradients in the two directions. It is thought that flow instability should first occur at the position of Kmax which may be the most dangerous position. This speculation is confirmed by Nishioka et al's experimental data. Comparison with experimental data for plane Poiseuille flow and pipe Poiseuille flow indicates that the proposed idea is really valid. It is found that the turbulence transition takes place at a critical value of Kmax of about 385 for both plane Poiseuille flow and pipe Poiseuille flow, below which no turbulence will occur regardless the disturbance. More studies show that the theory is also valid for plane Couette flows and Taylor-Couette flows between concentric rotating cylinders.

Hua-Shu Dou

2005-01-28T23:59:59.000Z

167

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

SciTech Connect

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

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

1994-02-01T23:59:59.000Z

168

Mechanisms underlying cellular responses of cells from haemopoeitic tissue  

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

underlying cellular responses of cells from haemopoeitic tissue underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation Munira Kadhim Oxford Brookes University Abstract Radiation-induced responses at the cellular and whole body levels are influenced by genetic predisposition, with implications for environmental and potentially, diagnostic exposures. Currently, the extent to which genetic background play a role in the mechanisms and signalling pathways involved in radiation-induced delayed Genomic Instability (GI) is not fully understood. In previous studies, our results have shown that the CBA/H and C57BL/6 mouse strains, have differing sensitivities in the induction of radiation-induced genomic instability (RIGI) in terms of chromosomal instability, following exposure to high dose-high LET and high dose-low LET

169

Elliptic and magneto-elliptic instabilities of disk vortices  

E-Print Network (OSTI)

Vortices are the fundamental units of turbulent flow. Understanding their stability properties therefore provides fundamental insights on the nature of turbulence itself. In this contribution I briefly review the phenomenological aspects of the instability of elliptic streamlines, in the hydro (elliptic instability) and hydromagnetic (magneto-elliptic instability) regimes. Vortex survival in disks is a balance between vortex destruction by these mechanisms, and vortex production by others, namely, the Rossby wave instability and the baroclinic instability.

Lyra, Wlad

2013-01-01T23:59:59.000Z

170

Numerical prediction of interfacial instabilities: Sharp interface method (SIM)  

Science Conference Proceedings (OSTI)

We introduce a sharp interface method (SIM) for the direct numerical simulation of unstable fluid-fluid interfaces. The method is based on the level set approach and the structured adaptive mesh refinement technology, endowed with a corridor of irregular, ... Keywords: Gas-liquid interfaces, Instability-seeding in numerical simulations, Interfacial flows, Interfacial instability, Rayleigh-Taylor instability, Sharp-interface treatment, Viscous Kelvin-Helmholtz instability, Yih instability

R. R. Nourgaliev; M. -S. Liou; T. G. Theofanous

2008-04-01T23:59:59.000Z

171

Eukaryotic Genomics Data from the DOE Joint Genome Institute (JGI)  

DOE Data Explorer (OSTI)

From the JGI webportal users can choose Eukaryotic genomes from a photo list, access the JGI FTP directories to download data files, use the Tree of Life navigation tool, or choose a genome and go directly to a website specific to that one genome. The individual sites include direct access to download sequence files, BLAST, search, view and navigate the genomic annotations.

172

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

Science Conference Proceedings (OSTI)

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

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

2014-01-01T23:59:59.000Z

173

Structural Genomics | Biosciences Division  

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

Chart Site Index Inside BIO BIO Safety About Argonne Midwest Center for Structural Genomics Andrzej Joachimiak Director Bldg: 202. Room: Q 118 E-mail: andrzejj@anl.gov Phone:...

174

Comparative genomics of the core and accessory genomes of 48 Sinorhizobium strains comprising five genospecies  

E-Print Network (OSTI)

annotation and comparative genomics. Database (Oxford) 2009,et al. : Comparative genomics of the core and accessoryComparative genomics of the core and accessory genomes of 48

2013-01-01T23:59:59.000Z

175

Capillary instability on a hydrophilic stripe  

E-Print Network (OSTI)

A recent experiment showed that cylindrical segments of water filling a hydrophilic stripe on an otherwise hydrophobic surface display a capillary instability when their volume is increased beyond the critical volume at which their apparent contact angle on the surface reaches ninety degrees (Gau et al., Science, 283, 1999). Surprisingly, the fluid segments did not break up into droplets -- as would be expected for a classical Rayleigh-Plateau instability -- but instead displayed a long-wavelength instability where all excess fluid gathered in a single bulge along each stripe. We consider here the dynamics of the flow instability associated with this setup. We perform a linear stability analysis of the capillary flow problem in the inviscid limit. We first confirm previous work showing that that all cylindrical segments are linearly unstable if (and only if) their apparent contact angle is larger than ninety degrees. We then demonstrate that the most unstable wavenumber for the surface perturbation decreases to zero as the apparent contact angle of the fluid on the surface approaches ninety degrees, allowing us to re-interpret the creation of bulges in the experiment as a zero-wavenumber capillary instability. A variation of the stability calculation is also considered for the case of a hydrophilic stripe located on a wedge-like geometry.

Raymond L. Speth; Eric Lauga

2009-04-30T23:59:59.000Z

176

An hydrodynamic shear instability in stratified disks  

E-Print Network (OSTI)

We discuss the possibility that astrophysical accretion disks are dynamically unstable to non-axisymmetric disturbances with characteristic scales much smaller than the vertical scale height. The instability is studied using three methods: one based on the energy integral, which allows the determination of a sufficient condition of stability, one using a WKB approach, which allows the determination of the necessary and sufficient condition for instability and a last one by numerical solution. This linear instability occurs in any inviscid stably stratified differential rotating fluid for rigid, stress-free or periodic boundary conditions, provided the angular velocity $\\Omega$ decreases outwards with radius $r$. At not too small stratification, its growth rate is a fraction of $\\Omega$. The influence of viscous dissipation and thermal diffusivity on the instability is studied numerically, with emphasis on the case when $d \\ln \\Omega / d \\ln r =-3/2$ (Keplerian case). Strong stratification and large diffusivity are found to have a stabilizing effect. The corresponding critical stratification and Reynolds number for the onset of the instability in a typical disk are derived. We propose that the spontaneous generation of these linear modes is the source of turbulence in disks, especially in weakly ionized disks.

B. Dubrulle; L. Mari; Ch. Normand; D. Richard; F. Hersant; J. -P. Zahn

2004-10-08T23:59:59.000Z

177

Frequency Instability Problems in North American Interconnections  

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

Frequency Instability Problems in Frequency Instability Problems in North American Interconnections May 1, 2011 DOE/NETL-2011/1473 Frequency Instability Problems in North American Interconnections Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

178

Studies of eRHIC coherent instabilities  

Science Conference Proceedings (OSTI)

In the presence of an effective coherent electron cooling, the rms ion bunch length in eRHIC will be kept at 8.3 cm for 250 GeV protons, which is much shorter than the current RHIC 45 cm rms bunch length. Together with the increased bunch intensity and total bunch number, coherent instabilities could be a potential limitation for achieving desired machine performance. In this study, we use the tracking code TRANFT to find thresholds and growth rates for single bunch and coupled bunch instabilities with linear chromaticity and amplitude dependent tune shift taken into account. Based on the simulation results, requirements of machine parameters such as rf voltage, linear chromaticity, and tune dependence of betatron amplitude are specified to suppress these instabilities.

Wang G.; Blaskiewicz, M.

2012-05-20T23:59:59.000Z

179

Ergoregion instability of ultracompact astrophysical objects  

Science Conference Proceedings (OSTI)

Most of the properties of black holes can be mimicked by horizonless compact objects such as gravastars and boson stars. We show that these ultracompact objects develop a strong ergoregion instability when rapidly spinning. Instability time scales can be of the order of 0.1 seconds to 1 week for objects with mass M=1-10{sup 6}M{sub {center_dot}} and angular momentum J>0.4M{sup 2}. This provides a strong indication that ultracompact objects with large rotation are black holes. Explosive events due to ergoregion instability have a well-defined gravitational-wave signature. These events could be detected by next-generation gravitational-wave detectors such as Advanced LIGO or LISA.

Cardoso, Vitor; Pani, Paolo; Cadoni, Mariano; Cavaglia, Marco [Department of Physics and Astronomy, University of Mississippi, University, MI 38677-1848 (United States); Dipartimento di Fisica, Universita di Cagliari, Cittadella Universitaria 09042 Monserrato (Italy) and Department of Physics and Astronomy, University of Mississippi, University, MI 38677-1848 (United States); Dipartimento di Fisica, Universita di Cagliari, and INFN sezione di Cagliari, Cittadella Universitaria 09042 Monserrato (Italy); Department of Physics and Astronomy, University of Mississippi, University, MI 38677-1848 (United States)

2008-06-15T23:59:59.000Z

180

Current-driven instability of magnetic jets  

E-Print Network (OSTI)

MHD instabilities can be responsible for the complex morphology of astrophysical jets. We consider the stability properties of jets containing both the azimuthal and axial field of subthermal strength. The presence of the magnetic field with complex topology in jets is suggested by theoretical models and it is consistent with recent observations. Stability is discussed by means of a linear analysis of the ideal MHD equations.We argue that, in the presence of azimuthal and axial magnetic fields, the jet is always unstable to non-axisymmetric perturbations. Stabilization does not occur even if the strengths of these field components are comparable. If the axial field is weaker than the azimuthal one, instability occurs for perturbations with any azimuthal wave number $m$, and the growth rate reach a saturation value for small values of $m$. If the axial field is stronger than the toroidal one, the instability shows off for perturbations with relatively large $m$.

Bonanno, Alfio

2010-01-01T23:59:59.000Z

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


181

Numerical simulations on electrostatic hydrogen cyclotron instabilities  

DOE Green Energy (OSTI)

Both one- and two-dimensional particle simulation models have been used to study the nonlinear behavior of the electrostatic hydrogen cyclotron instabilities driven by the electron current along magnetic field. It is found that the instability saturates as a result of electron velocity space diffusion along magnetic field. The cyclotron waves remain highly coherent in the nonlinear stage. When the electron drift speed is comparable to thermal speed, substantial ion heating as well as particle cross-field diffusion comparable to Bohm diffusion has been observed. Comparisons of the simulation results with the theoretical predictions and the observations in both laboratory and space plasmas are discussed.

Okuda, H.; Cheng, C.Z.; Lee, W.W.

1981-02-01T23:59:59.000Z

182

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

Science Conference Proceedings (OSTI)

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

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

2012-09-01T23:59:59.000Z

183

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

SciTech Connect

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

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

2012-11-01T23:59:59.000Z

184

DNA damage induced clusterin expression - A sensitive measure of genomic  

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

damage induced clusterin expression - A sensitive measure of genomic damage induced clusterin expression - A sensitive measure of genomic instability David Boothman University of Texas Southwestern Medical Center at Dallas Abstract Secretory clusterin (sCLU) is a glycoprotein secreted from cells following exposure to genotoxic stress, and sCLU expression is elevated in many different disease states. sCLU is a pro-survival protein that acts as a molecular chaperone to remove cell debris caused by trauma to cells and tissues in vivo. sCLU expression is extremely sensitive to oxidative stress and DNA damage and can be induced by low dose ionizing radiation (LDIR), as low as 2 cGy. We previously demonstrated that sCLU was induced after LDIR by activation of the Insulin-like Growth Factor 1 Receptor (IGF-1R), and downstream stimulation of Src/MAPK/Erk-1/2 to promote binding of the Egr-1

185

Evolutionary Genomics of Life in (and from) the Sea  

E-Print Network (OSTI)

web Genomes Online NIH Genome Sequencing Input NIH GenomesAbstract High throughput genome sequencing centers that werefunding sources of genome sequencing in the United States,

Boore, Jeffrey L.

2009-01-01T23:59:59.000Z

186

Genomics, Gene Expression and Other Studies in Soybean Rust  

E-Print Network (OSTI)

Joint Genome Institute Genomics, Gene Expression and otherRust Martha Luca Posada-Buitrago Ph.D Genomics DivisionEvolutionary Genomics DOE- Joint Genome Institute Lawrence

Posada-Buitrago, Martha Lucia

2005-01-01T23:59:59.000Z

187

Fueling the Future with Fungal Genomics  

E-Print Network (OSTI)

et al. 2008. Fungal genome sequencing and bioenergy. FungalCullen D, et al. 2008. Genome sequencing and analysis of theand lessons learned from genome sequencing. Methods Enzymol.

Grigoriev, Igor V.

2011-01-01T23:59:59.000Z

188

DOE Joint Genome Institute 2008 Progress Report  

E-Print Network (OSTI)

Martinez, D. , et al. Genome sequencing and analysis of thegroup, the HudsonAlpha Genome Sequencing Center, will expandnext-genera- tion genome sequencing and add capabilities to

Gilbert, David

2009-01-01T23:59:59.000Z

189

Requirements and standards for organelle genome databases  

E-Print Network (OSTI)

to the complete genome sequencing of many other organisms (guide the transition from human genome sequencing to being a04334; and Phakopsora genome sequencing direct funding).

Boore, Jeffrey L.

2006-01-01T23:59:59.000Z

190

DOE JGI Microbial Genomics & Metagenomics Workshops  

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

DOE Joint Genome Institute Microbial Genomics & Metagenomics Workshops Walnut Creek, California The U.S. Department of Energy Joint Genome Institute (DOE JGI) will be offering...

191

VISTA - computational tools for comparative genomics  

E-Print Network (OSTI)

tools for comparative genomics Kelly A. Frazer 1 , LiorBerkeley, CA, 94720 Genomics Division, Lawrence Berkeleymultiple comparative genomics tools and provides users with

Frazer, Kelly A.; Pachter, Lior; Poliakov, Alexander; Rubin, Edward M.; Dubchak, Inna

2004-01-01T23:59:59.000Z

192

Fueling the Future with Fungal Genomics  

E-Print Network (OSTI)

JW. 2010. China's fungal genomics initiative: a whitepaper.and Saccharomycotina. BMC Genomics. 8, 325. Bailly J,Harnessing ectomycorrhizal genomics for ecological insights.

Grigoriev, Igor V.

2011-01-01T23:59:59.000Z

193

JGI - Structural Genomics Program  

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

Structural Genomics Program Structural Genomics Program The structural characterization of proteins of unknown function can be described as structural genomics, an approach in which structure determination by X-ray crystallography supplies key functional information. This is exemplified by studies of the carboxysome. The structures of the first carboxysome shell proteins (Kerfeld et al., Science 2005) confirmed earlier hypotheses that they are indeed the basic building blocks of the carboxysome shell; the quaternary structure and the higher order assemblies of the proteins in the crystals provided insight into how they assemble into shell facets. Likewise, our structure of the carboxysome component CsoS3 revealed that it was a member of the beta-carbonic family, despite having no detectable sequence homology at the level of primary structure

194

Radiation-induced gene responses  

SciTech Connect

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

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

1996-12-31T23:59:59.000Z

195

Saturation Point Representation of Cloud-Top Entrainment Instability  

Science Conference Proceedings (OSTI)

Cloud-top entrainment instability was investigated using a mixing line analysis. Mixing time scales are closely related to the actual size of the parcel, so that local instabilities are largely dependent on the scales of mixing near the cloud ...

Reinout Boers

1991-11-01T23:59:59.000Z

196

The Use and Misuse of Conditional Symmetric Instability  

Science Conference Proceedings (OSTI)

A commonly employed explanation for single- and multiple-banded clouds and precipitation in the extratropics is slantwise convection due to the release of moist symmetric instability (MSI), of which one type is conditional symmetric instability (...

David M. Schultz; Philip N. Schumacher

1999-12-01T23:59:59.000Z

197

Lagrangian Study of Tropical Instability Vortices in the Atlantic  

Science Conference Proceedings (OSTI)

Tropical instability waves and tropical instability vortices (TIVs) exert major controls on ocean dynamics, thermodynamics, and biology on intraseasonal to seasonal time scales. To understand the fundamental mechanisms at play, a Lagrangian ...

Pierre Dutrieux; Christophe E. Menkes; Jerome Vialard; Pierre Flament; Bruno Blanke

2008-02-01T23:59:59.000Z

198

Hydromagnetic Instability in Differentially Rotating Flows  

E-Print Network (OSTI)

We study the stability of a compressible differentially rotating flows in the presence of the magnetic field, and we show that the compressibility profoundly alters the previous results for a magnetized incompressible flow. The necessary condition of newly found instability can be easily satisfied in various flows in laboratory and astrophysical conditions and reads $B_{s} B_{\\phi} \\Omega' \

Bonanno, A

2006-01-01T23:59:59.000Z

199

Transverse instability in high intensity proton rings  

SciTech Connect

In recent years, many applications are being considered for low energy high intensity proton synchrotrons. Most high intensity proton rings are at low energy below transition. Several aspects of the beam dynamics of this kind of rings are different from the electron or high energy rings. The transverse microwave instabilities will be discussed in this article.

Zhang, S.Y.; Weng, W.T.

1997-07-01T23:59:59.000Z

200

An Instability of Mature Cold Fronts  

Science Conference Proceedings (OSTI)

An instability of a cold front possessing a low-level warm-band precursor is examined within an f-plane, quasi- and semigeostrophic framework. The basic frontal state is taken to be two-dimensional and of uniform potential vorticity. Theoretical ...

Christoph Schr; Huw C. Davies

1990-04-01T23:59:59.000Z

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


201

Free Rossby Wave Instability at Finite Amplitude  

Science Conference Proceedings (OSTI)

The finite-amplitude evolution of the instability of a nonparallel basic-state flow and the basic state are studied. The basic state consists of a free Rossby wave in an inviscid, barotropic beta-plane model. The method of multiple time scales is ...

Richard C. Deininger

1982-03-01T23:59:59.000Z

202

Nonlinear MHD instabilities in elongated cylinders  

SciTech Connect

The nonlinear evolution of fixed-boundary instabilities was studied using a 3-D ideal-MHD computer simulation. The effect of elongation and peaked profile is studied. It is found that the dominant process is convection around essentially fixed velocity vortex cells. (auth)

Bateman, G.; Hicks, H.R.; Wooten, J.W.

1975-01-01T23:59:59.000Z

203

Microbial Genomics Data from the DOE Joint Genome Institute (JGI)  

DOE Data Explorer (OSTI)

As of March 2008, The Joint Genome Institute has released 296 Prokaryotic microbial sites, with 216 in finished status.

204

Genomic Advances to Improve Biomass for Biofuels (Genomics and Bioenergy)  

DOE Green Energy (OSTI)

Lawrence Berkeley National Lab bioscientist Daniel Rokhsar discusses genomic advances to improve biomass for biofuels. He presented his talk Feb. 11, 2008 in Berkeley, California as part of Berkeley Lab's community lecture series. Rokhsar works with the U.S. Department of Energy's Joint Genome Institute and Berkeley Lab's Genomics Division.

Rokhsar, Daniel

2008-02-11T23:59:59.000Z

205

Nonlinear fan instability of electromagnetic waves  

Science Conference Proceedings (OSTI)

This paper studies the linear and nonlinear stages of the fan instability, considering electromagnetic waves of the whistler frequency range interacting resonantly with energetic electron fluxes in magnetized plasmas. The main attention is paid to determine the wave-particle interaction processes that can lead to the excitation of intense electromagnetic waves by nonequilibrium particle distributions involving suprathermal tails, and to explain under what conditions and through what mechanisms they can occur, develop, and saturate. This paper presents and discusses two main processes: (i) the linear fan instability and (ii) the nonlinear process of dynamical resonance merging, which can significantly amplify the energy carried by linearly destabilized waves after they saturate due to particle trapping. This study consists of (i) determining analytically and numerically, for parameters typical of space and laboratory plasmas, the linear growth rates of whistlers excited by suprathermal particle fluxes through the fan instability, as well as the corresponding thresholds and the physical conditions at which the instability can appear, (ii) building a theoretical self-consistent 3D model and a related numerical code for describing the nonlinear evolution of the wave-particle system, and (iii) performing numerical simulations to reveal and characterize the nonlinear amplification process at work, its conditions of development, and its consequences, notably in terms of electromagnetic wave radiation. The simulations show that when the waves have reached sufficient energy levels owing to the linear fan instability, they saturate by trapping particles and due to the complex dynamics of these particles in the electromagnetic fields, the resonant velocities' domains of the waves overlap and merge, meanwhile a strong increase of the wave energy occurs.

Krafft, C. [Laboratoire de Physique des Plasmas, Ecole Polytechnique, 91128 Palaiseau Cedex (France) and University Paris Sud, 91405 Orsay Cedex (France); Volokitin, A. [Space Research Institute (IKI), 117997, 84/32 Profsoyuznaya Str., Moscow (Russian Federation)

2010-10-15T23:59:59.000Z

206

Chemical and mechanical spinodals a unique liquid-gas instability  

E-Print Network (OSTI)

We demonstrate that the instabilities of asymmetric nuclear matter at sub-saturation densities do not present two types of instabilities as usually discussed but a unique one. The associated order parameter is everywhere dominated by the isoscalar density and so the transition is of liquid-gas type even in the so-called chemical instability region.

Philippe Chomaz; Jerome Margueron

2003-03-11T23:59:59.000Z

207

Weibel instabilities in a completely degenerate electron Fermi gas  

SciTech Connect

Weibel instability in a degenerate Fermi plasma is studied. A new type of quantum Weibel instabilities is disclosed. In particular, a novel oscillatory Weibel instability is found and its growth rate is obtained. A transverse zero sound in a quantum degenerate electron gas, which has no counterpart in the classical consideration, is revealed.

Tsintsadze, Levan N. [Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)

2009-09-15T23:59:59.000Z

208

Mammalian comparative genomics and epigenomics  

E-Print Network (OSTI)

The human genome sequence can be thought of as an instruction manual for our species, written and rewritten over more than a billion of years of evolution. Taking a complete inventory of our genome, dissecting its genes ...

Mikkelsen, Tarjei Sigurd, 1978-

2009-01-01T23:59:59.000Z

209

Life Sciences & Genomics Division Diversity  

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

Sciences & Genomics Diversity imagemap Workforce Diversity Action Plans title Diversity Committee Employment Opportunities Community Outreach Activities htmlempopps.html Read...

210

Communicating Genomics:GTL  

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

DOE Joint Genome Institute User Meeting Sponsored By U.S. Department of Energy Office of Science March 24-26, 2010 Walnut Creek Marriott Walnut Creek, California iii Contents Speaker Presentations ......................................................................................... 1 Poster Presentations........................................................................................... 11 Attendees............................................................................................................. 67 Author Index ...................................................................................................... 75 iv Posters alphabetical by first author. *Presenting author 1 Speaker Presentations Abstracts alphabetical by speaker

211

Genome in a Bottle Consortium Workshop  

Science Conference Proceedings (OSTI)

Genome in a Bottle Consortium Workshop. Purpose: NIST ... well. Related Project(s): Genome in a Bottle Consortium. Details: ...

2013-08-13T23:59:59.000Z

212

DOE Joint Genome Institute: Establishing Standard Definitions for Genome  

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

October 8, 2009 October 8, 2009 Establishing Standard Definitions for Genome Sequences Download a podcast of this release! WALNUT CREEK, CA-In 1996, researchers from major genome sequencing centers around the world convened on the island of Bermuda and defined a finished genome as a gapless sequence with a nucleotide error rate of one or less in 10,000 bases. This effectively set the quality target for the human genome effort and was quickly applied to other genome projects. If a genome sequence didn't meet this stringent criterion, it was simply considered a "draft." More than a decade later, researchers are finding that with the advent of the latest sequencing technologies the terms "draft" and "finished" are no longer sufficient to describe the varying levels of genome sequence

213

LANL | Physics | Hydrodynamic Material Instabilities at extremes  

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

Understanding hydrodynamic material instabilities at extremes Understanding hydrodynamic material instabilities at extremes The National Nuclear Security Administration science-based stockpile stewardship program funds research that will improve critical physics-based dynamic materials models. Los Alamos National Laboratory and Lawrence Livermore National Laboratory, as nuclear weapon design laboratories, are mandated to predict the reliability and durability of the nuclear weapons stockpile. This is done using state-of-the-art supercomputers and computer codes. It is also important to have state-of-the-art physics models in these codes. Los Alamos has theory experts in dynamic materials, thus creating powerful working groups when combined with experimental experts in Physics Division and elsewhere. Key to the science-based stockpile stewardship program is making

214

Patterns and instability of grannular flow  

Science Conference Proceedings (OSTI)

Dense granular flows are often observed to become unstable and form inhomogeneous structures in nature or industry. Although recently significant advances have been made in understanding simple flows, instabilities are often not understood in detail. We present experimental and numerical results that show the formation of longitudinal stripes. These arise from instability of the uniform flowing state of granular media on a rough inclined plane. The form of the stripes depends critically on the mean density of the flow with a robust form of stripes at high density that consists of fast sliding plug-like regions (stripes) on top of highly agitated boiling material -- a configuration reminiscent of the Leidenfrost effect when a droplet of liquid lifted by its vapor is hovering above a hot surface.

Ecke, Robert E [Los Alamos National Laboratory; Borzsonyi, Tamas [NON LANL; Mcelwaine, Jim N [U. CAMBRIDGE

2009-01-01T23:59:59.000Z

215

Solar Dynamo and Toroidal Field Instabilities  

E-Print Network (OSTI)

The possibility of non-axisimmetric (kink) instabilities of a toroidal field seated in the tachocline is much discussed in the literature. In this work, the basic properties of kink and quasi-interchange instabilities, produced by mixed toroidal and poloidal configuration, will be briefly reviewed. In particular it will be shown that the unstable modes are strongly localized near the Equator and not near the Poles as often claimed in the literature. Based on the results of recent numerical simulations, it is argued that a non-zero helicity can already be produced at a non-linear level. A mean-field solar dynamo is then constructed with a positive $\\alpha$-effect in the overshoot layer localized near the Equator and a meridional circulation with a deep return flow. Finally, the possibility that the solar cycle is driven by a $\\alpha\\Omega$ dynamo generated by the negative subsurface shear in the supergranulation layer will also be discussed.

Bonanno, Alfio

2012-01-01T23:59:59.000Z

216

JGI - Intro to Genomics 1  

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

An Introduction to Genomics: The Human Genome and Beyond An Introduction to Genomics: The Human Genome and Beyond 1 | 2 | 3 | 4 | Next>> What is genomics? THE HUMAN BODY consists of trillions of cells. Almost all contain an entire genome--the complete set of inherited genetic information encoded in our DNA. When humans reproduce, the parents' sperm and egg DNA combine to contribute a genome's worth of genetic information to the fertilized embryo. That same information is in each of the cells that eventually make up an organism. cell, DNA helix, and protein structure Some segments of DNA, called genes or "coding" DNA, contain the chemical recipe that determines particular traits; genetics is the study of the inheritance and function of these genes. Scientists now estimate that humans have about 30,000 genes, located along threadlike, tightly coiled

217

Enhancing the Electrooptic Effect Using Modulation Instability  

E-Print Network (OSTI)

As electronic operating frequencies increase toward the terahertz regime, new electrooptic modulators capable of low-voltage high-frequency operation must be developed to provide the necessary optical interconnects. This letter presents a new concept that exploits modulation instability to enhance the intrinsically weak electrooptic effect, \\chi^(2). Simulations demonstrate more than 50 times enhancement of electrooptic effect at millimeter wave frequencies leading to a substantial reduction in the required modulation voltage.

DeVore, Peter T S; Jalali, Bahram

2013-01-01T23:59:59.000Z

218

Nonabelian plasma instabilities in Bjorken expansion  

E-Print Network (OSTI)

Plasma instabilities are parametrically the dominant nonequilibrium dynamics of a weakly coupled quark-gluon plasma. In recent years the time evolution of the corresponding collective colour fields has been studied in stationary anisotropic situations. Here I report on recent numerical results on the time evolution of the most unstable modes in a longitudinally expanding plasma as they grow from small rapidity fluctuations to amplitudes where non-Abelian self-interactions become important.

Anton Rebhan

2008-10-15T23:59:59.000Z

219

Gravitational Instability in Radiation Pressure Dominated Backgrounds  

E-Print Network (OSTI)

I consider the physics of gravitational instabilities in the presence of dynamically important radiation pressure and gray radiative diffusion, governed by a constant opacity, kappa. For any non-zero radiation diffusion rate on an optically-thick scale, the medium is unstable unless the classical gas-only isothermal Jeans criterion is satisfied. When diffusion is "slow," although the dynamical Jeans instability is stabilized by radiation pressure on scales smaller than the adiabatic Jeans length, on these same spatial scales the medium is unstable to a diffusive mode. In this regime, neglecting gas pressure, the characteristic timescale for growth is independent of spatial scale and given by (3 kappa c_s^2)/(4 pi G c), where c_s is the adiabatic sound speed. This timescale is that required for a fluid parcel to radiate away its thermal energy content at the Eddington limit, the Kelvin-Helmholz timescale for a radiation pressure supported self-gravitating object. In the limit of "rapid" diffusion, radiation does nothing to suppress the Jeans instability and the medium is dynamically unstable unless the gas-only Jeans criterion is satisfied. I connect with treatments of Silk damping in the early universe. I discuss several applications, including photons diffusing in regions of extreme star formation (starburst galaxies & pc-scale AGN disks), and the diffusion of cosmic rays in normal galaxies and galaxy clusters. The former (particularly, starbursts) are "rapidly" diffusing and thus cannot be supported against dynamical instability in the linear regime by radiation pressure alone. The latter are more nearly "slowly" diffusing. I speculate that the turbulence in starbursts may be driven by the dynamical coupling between the radiation field and the self-gravitating gas, perhaps mediated by magnetic fields. (Abridged)

Todd A. Thompson

2008-04-21T23:59:59.000Z

220

Forecasting Random Walks Under Drift Instability  

E-Print Network (OSTI)

Forecasting Random Walks Under Drift Instability? M. Hashem Pesaran University of Cambridge, CIMF, and USC Andreas Pick University of Cambridge, CIMF March 11, 2008 Abstract This paper considers forecast averaging when the same model is used... but estimation is carried out over different estimation windows. It develops theoretical results for random walks when their drift and/or volatility are subject to one or more structural breaks. It is shown that compared to using forecasts based on a single...

Pesaran, M Hashem; Pick, Andreas

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


221

Low Dose Radiation Research Program: Howard L. Liber  

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

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

222

Digital instability of a confined elastic meniscus  

E-Print Network (OSTI)

Thin soft elastic layers serving as joints between relatively rigid bodies may function as sealants, thermal, electrical, or mechanical insulators, bearings, or adhesives. When such a joint is stressed, even though perfect adhesion is maintained, the exposed free meniscus in the thin elastic layer becomes unstable, leading to the formation of spatially periodic digits of air that invade the elastic layer, reminiscent of viscous fingering in a thin fluid layer. How- ever, the elastic instability is reversible and rate-independent, dis- appearing when the joint is unstressed. We use theory, experiments, and numerical simulations to show that the transition to the digital state is sudden (first-order), the wavelength and amplitude of the fingers are proportional to the thickness of the elastic layer, and the required separation to trigger the instability is inversely proportional to the in-plane dimension of the layer. Our study reveals the energetic origin of this instability and has implications for the strength of polymeric adhesives; it also suggests a method for patterning thin films reversibly with any arrangement of localized fingers in a digital elastic memory, which we confirm experimentally.

John S. Biggins; Baudouin Saintyves; Zhiyan Wei; Elisabeth Bouchaud; L. Mahadevan

2013-08-13T23:59:59.000Z

223

Thermalization and the chromo-Weibel instability  

E-Print Network (OSTI)

Despite the apparent success of ideal hydrodynamics in describing the elliptic flow data which have been produced at Brookhaven National Lab's Relativistic Heavy Ion Collider, one lingering question remains: is the use of ideal hydrodynamics at times t < 1 fm/c justified? In order to justify its use a method for rapidly producing isotropic thermal matter at RHIC energies is required. One of the chief obstacles to early isotropization/thermalization is the rapid longitudinal expansion of the matter during the earliest times after the initial nuclear impact. As a result of this expansion the parton distribution functions become locally anisotropic in momentum space. In contrast to locally isotropic plasmas anisotropic plasmas have a spectrum of soft unstable modes which are characterized by exponential growth of transverse chromo-magnetic/-electric fields at short times. This instability is the QCD analogue of the Weibel instability of QED. Parametrically the chromo-Weibel instability provides the fastest method for generation of soft background fields and dominates the short-time dynamics of the system.

Michael Strickland

2007-01-29T23:59:59.000Z

224

Genomics Division Home  

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

PIs PIs Mark Biggin Jim Bristow Jan-Fang Cheng Inna Dubchak Suzanna Lewis Chris Mungall Len Pennacchio Eddy Rubin Axel Visel Divisional Information Support Staff Seminars Diversity Directory Contact Us The characterization and analysis of genome sequences from such diverse organisms as humans to the most primitive soil microbe represent a watershed opportunity for biology. The Genomics Division is taking advantage of this wealth of new information. While it is well known that DNA encodes the basic blue print of life, it is not known how best to interpret most of this information. To address this question, laboratories within the division are developing computational, biochemical, genetic, and imaging methods to decipher the complex sequence motifs that control RNA transcription, DNA replication, and chromosome structure. The Division is

225

Genetic analysis of the role of RNaseH2 in preventing genome instability  

E-Print Network (OSTI)

Evidence suggesting that Pif1 helicase functions in DNAreplication with the Dna2 helicase/nuclease and DNABoeke, J.D. (2003). DNA helicase gene interaction network

Soltero, Stephanie Ruth

2009-01-01T23:59:59.000Z

226

Overexpressed of RAD51 suppresses recombination defects: a possible mechanism to reverse genomic instability  

E-Print Network (OSTI)

Sasaki, M.S. , Sonoda, E. , Fukushima, T. , Morrison, C. ,M.S. , Tachiiri, S. , Fukushima, T. , Sonoda, E. , Schild,

Schild, David

2010-01-01T23:59:59.000Z

227

Rac1b and reactive oxygen species mediate MMP-3-induced EMT and genomic instability  

E-Print Network (OSTI)

. A. et al. Cell transformation by the superoxide-generating oxidase Mox1. Nature 401, 79­-82 (1999

Nelson, Celeste M.

228

The US Department of Energy Joint Genome Institute Microbial Genome Program  

E-Print Network (OSTI)

Institute A typical genome sequencing project AssemblyInstitute A typical genome sequencing project AssemblyJGI Microbial Sequencing US DOE Joint Genome Institute JGI

Lapidus, Alla

2005-01-01T23:59:59.000Z

229

A physical map of the papaya genome with integrated genetic map and genome sequence  

E-Print Network (OSTI)

As a part of the genome sequencing project, we constructed ational papaya whole genome sequencing may be carried out inframework to guide the genome sequencing of related species.

2009-01-01T23:59:59.000Z

230

Comparative genomic analysis of fungal genomes reveals intron-rich ancestors  

E-Print Network (OSTI)

remain debated. Genome sequencing and comparative analysisInternational Human Genome Sequencing Consortium: Finishingreinhardtii genome structure using large-scale sequencing of

Stajich, Jason E; Dietrich, Fred S; Roy, Scott W

2007-01-01T23:59:59.000Z

231

Mitochondrial genome sequences and comparative genomics of Phytophthora ramorum and P. sojae  

E-Print Network (OSTI)

sequences and comparative genomics of Phytophthora ramorumAnnotation and comparative genomics - Annotation of codingtools for comparative genomics. Nuc Acids Res July 1:32:

Martin, Frank N.; Douda, Bensasson; Tyler, Brett M.; Boore, Jeffrey L.

2007-01-01T23:59:59.000Z

232

Coral Reef Genomics: Developing tools for functional genomics of coral symbiosis  

E-Print Network (OSTI)

Coral Reef Genomics: Developing toolsfor functional genomics of coral symbiosis Jodi SCHWARZ 1 ,symbiosis functional genomics cDNA microarray ABSTRACT

Schwarz, Jodi; Brokstein, Peter; Manohar, Chitra; Coffroth, Mary Alice; Szmant, Alina; Medina, Monica

2008-01-01T23:59:59.000Z

233

Microsoft PowerPoint - Powerpoint_Genomicinstability.ppt [Compatibility Mode]  

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

Instability Instability y Delayed Genetic Effects What is Genomic Instability? What is Genomic Instability? * Often, after being damaged by radiation, cells are able to repair DNA damage and reproduce normally normally. * However, sometimes damage may carry over for several generations before the unobserved damage g g causes the cell to lose control of its genome. * At this point, cells may be unable to reproduce f ll Th b i ll successfully. They may become genetically unstable, or become cancerous. Radiation-induced Genetic Damage Old Paradigm After a cell is mutated by radiation, all of its prodigy are mutated Mutation is a rare event that cannot be altered. Genomic Instability New Paradigm After a cell is exposed to radiation, biological changes are produced that, after many cell divisions, result in loss of genetic

234

DOE Joint Genome Institute: Brown Tide Culprit Sequenced: Genome...  

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

Culprit Sequenced: Genome of the First of Algal Bloom Species WALNUT CREEK, Calif.- Algae play key roles in the global carbon cycle, helping sequester significant amounts of...

235

Investigation of tearing instability phenomena in ASTM A106 steel  

SciTech Connect

An experimental investigation was performed to evaluate tearing instability theory by varying the applied tearing modulus, T/sub applied/, so that fracture instability would be initiated at various levels of stable crack extension. This is an extension of past investigations of tearing instability theory in that crack extension was monitored continuously using the dc potential drop technique, enabling the applied and material tearing moduli to be calculated at the point of instability. The results of this investigation indicate that, in most cases, fracture instability occurred when the difference between the applied and material tearing moduli was on the order of 10%. Variations in the load versus displacement records of the specimens near maximum load due to local instabilities and friction in the load train precluded measurement of a smooth applied tearing modulus curve.

Link, R.E.; Hays, R.A.

1986-05-01T23:59:59.000Z

236

Computational methods and analyses in comparative genomics and epigenomics  

E-Print Network (OSTI)

promise of comparative genomics in mammals. Science, 286,homology relationships. Genomics, Dehal, P. and Boore, J.to plant comparative genomics. Genome Research, 13(5), 999

Peng, Qian

2012-01-01T23:59:59.000Z

237

Salt Stress in Desulfovibrio vulgaris Hildenborough: An integrated genomics approach  

E-Print Network (OSTI)

2002. Integrating cancer genomics and proteomics in theWeb site for comparative genomics. Genome Res 15:1015-22.Hildenborough: An integrated genomics approach. Aindrila

Mukhopadhyay, Aindrila

2010-01-01T23:59:59.000Z

238

Single Cell Whole Genome Amplification  

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

Single Cell Whole Genome Amplification Single Cell Whole Genome Amplification of Uncultivated Organisms Mircea Podar , Martin Keller , and Philip Hugenholtz (* ü ) Abstract Whole genome amplification of single cells is emerging as a powerful technique for accessing the genomes of individual members of microbial communi- ties without the complication of identifying the source of sequence data posed by shotgun sequencing of environmental samples (metagenomics). This method holds particular promise for the molecular unveiling of uncultivated organisms that com- prise the bulk of the microbial diversity and functionality on our planet. 1 Introduction Over the last two decades, it has become increasingly apparent that microbial diversity

239

ORNL Genome Analysis Pipeline - Eukaryotic  

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

Grail (Microbial Gene Prediction System Internet Link) GrailEXP Genome Analysis Pipeline DomainParser PROSPECT (PROtein Structure Prediction and Evaluation Computer...

240

genome109280 634..641  

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

(http: www.phytozome.net), Selaginella moellendorffii (http:www. phytozome.net), Sorghum bicolor (http:genome.jgi-psf.org Sorbi1), Vitis vinifera (http:...

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


241

Compressibility and local instabilities of differentially rotating magnetized gas  

E-Print Network (OSTI)

We study the stability of compressible cylindrical differentially rotating flow in the presence of the magnetic field, and show that compressibility alters qualitatively the stability properties of flows. Apart from the well-known magnetorotational instability that can occur even in incompressible flow, there exist a new instability caused by compressibility. The necessary condition of the newly found instability can easily be satisfied in various flows in laboratory and astrophysical conditions and reads $B_{s} B_{\\phi} \\Omega' \

Bonanno, A; Bonanno, Alfio; Urpin, Vadim

2007-01-01T23:59:59.000Z

242

Population genomics: Whole-genome analysis of polymorphism and divergence in Drosophila simulans  

E-Print Network (OSTI)

PLoS BIOLOGY Population Genomics: Whole-Genome Analysis ofwww.plosbiology.org Population Genomics of D. simulans Table11 | e310 Population Genomics of D. simulans Table S15. GO

2007-01-01T23:59:59.000Z

243

Instabilities in the Nuclear Energy Density Functional  

E-Print Network (OSTI)

In the field of Energy Density Functionals (EDF) used in nuclear structure and dynamics, one of the unsolved issues is the stability of the functional. Numerical issues aside, some EDFs are unstable with respect to particular perturbations of the nuclear ground-state density. The aim of this contribution is to raise questions about the origin and nature of these instabilities, the techniques used to diagnose and prevent them, and the domain of density functions in which one should expect a nuclear EDF to be stable.

M. Kortelainen; T. Lesinski

2010-02-05T23:59:59.000Z

244

Plasma planar filament instability and Alfven waves  

E-Print Network (OSTI)

Inhomogeneous plasmas filaments instabilities are investigated by using the techniques of classical differential geometry of curves where Frenet torsion and curvature describe completely the motion of curves. In our case the Frenet frame changes in time and also depends upon the other coordinates taking into account the inhomogeneity of the plasma. The exponential perturbation method so commonly used to describe cosmological perturbatons is applied to magnetohydrodynamic (MHD) plasma equations to find longitudinal modes describing Alfven waves propagation modes describing plasma waves in the medium. Stability is investigated in the imaginary axis of the spectra of complex frequencies ${\\omega}$ or $Im(\\omega)\

Garcia de Andrade

2007-03-05T23:59:59.000Z

245

Combustion Instability and Blowout Characteristics of Fuel Flexible...  

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

and Blowout Combustion Instability and Blowout Characteristics of Fuel Flexible Gas Turbine Characteristics of Fuel Flexible Gas Turbine Combustors Combustors Georgia...

246

Ion-Hose Instability in Long Pulse Induction Accelerators  

E-Print Network (OSTI)

The ion-hose (or fast-ion) instability sets limits on the allowable vacuum in a long-pulse, high current accelerator. Beam-induced ionization of the background gas leads to the formation of an ion channel which couples to the transverse motion of the beam. The instability is studied analytically and numerically for several ion frequency distributions. The effects of beam envelope oscillations on the growth of the instability will be discussed. The saturated non-linear growth of the instability is derived analytically and numerically for two different ion frequency distributions. 1

George J. Caporaso; Jim F. Mccarrick

2000-01-01T23:59:59.000Z

247

Oil-whirl instability in an automotive turbocharger.  

E-Print Network (OSTI)

??This thesis is concerned with a theoretical investigation into the nonlinear dynamic behaviour of a turbocharger. Specifically the instabilities due to oil-whirl are examined. These (more)

Kamesh, P.

2011-01-01T23:59:59.000Z

248

Interstellar Turbulent Magnetic Field Generation by Plasma Instabilities  

E-Print Network (OSTI)

The maximum magnetic field strength generated by Weibel-type plasma instabilities is estimated for typical conditions in the interstellar medium. The relevant kinetic dispersion relations are evaluated by conducting a parameter study both for Maxwellian and for suprathermal particle distributions showing that micro Gauss magnetic fields can be generated. It is shown that, depending on the streaming velocity and the plasma temperatures, either the longitudinal or a transverse instability will be dominant. In the presence of an ambient magnetic field, the filamentation instability is typically suppressed while the two-stream and the classic Weibel instability are retained.

Tautz, R C

2013-01-01T23:59:59.000Z

249

QCD plasma instability and thermalisation at heavy ion collisions  

E-Print Network (OSTI)

Under suitable non-equilibrium conditions QCD plasma can develop plasma instabilities, where some modes of the plasma grow exponentially. It has been argued that these instabilities can play a significant role in the thermalisation of the plasma in heavy-ion collision experiments. We study the instability in SU(2) plasmas using the hard thermal loop effective lattice theory, which is suitable for studying real-time evolution of long wavelength modes in the plasma. We observe that under suitable conditions the plasma can indeed develop an instability which can grow to a very large magnitude, necessary for the rapid thermalisation in heavy-ion collisions.

Dietrich Bodeker; Kari Rummukainen

2007-11-13T23:59:59.000Z

250

Summary of workshop session F on electron-cloud instabilities  

E-Print Network (OSTI)

like those in the PSR and SNS, the instability mechanismcloud effects in the SNS. With a uniform beam density, itrecently removed from the SNS baseline. 5. SIMULATIONS OF

Zimmermann, Frank; Wolski, Andrzej

2004-01-01T23:59:59.000Z

251

Transverse instability of the antiproton beam in the Recycler Ring  

SciTech Connect

The brightness of the antiproton beam in Fermilab's 8 GeV Recycler ring is limited by a transverse instability. This instability has occurred during the extraction process to the Tevatron for large stacks of antiprotons even with dampers in operation. This paper describes observed features of the instability, introduces the threshold phase density to characterize the beam stability, and finds the results to be in agreement with a resistive wall instability model. Effective exclusion of the longitudinal tails from Landau damping by decreasing the depth of the RF potential well is observed to lower the threshold density by up to a factor of two.

Prost, L.R.; Bhat, C.M.; Burov, A.; Crisp, J.; Eddy, N.; Hu, M.; Shemyakin, A.; /Fermilab

2011-03-01T23:59:59.000Z

252

Human Genome Program Image Gallery (from genomics.energy.gov)  

DOE Data Explorer (OSTI)

This collection contains approximately 240 images from the genome programs of DOE's Office of Science. The images are divided into galleries related to biofuels research, systems biology, and basic genomics. Each image has a title, a basic citation, and a credit or source. Most of the images are original graphics created by the Genome Management Information System (GMIS). GMIS images are recognizable by their credit line. Permission to use these graphics is not needed, but please credit the U.S. Department of Energy Genome Programs and provide the website http://genomics.energy.gov. Other images were provided by third parties and not created by the U.S. Department of Energy. Users must contact the person listed in the credit line before using those images. The high-resolution images can be downloaded.

253

Fermi Liquid Instabilities in the Spin Channel  

SciTech Connect

We study the Fermi surface instabilities of the Pomeranchuk type in the spin triplet channel with high orbital partial waves (F{sub l}{sup a} (l > 0)). The ordered phases are classified into two classes, dubbed the {alpha} and {beta}-phases by analogy to the superfluid {sup 3}He-A and B-phases. The Fermi surfaces in the {alpha}-phases exhibit spontaneous anisotropic distortions, while those in the {beta}-phases remain circular or spherical with topologically non-trivial spin configurations in momentum space. In the {alpha}-phase, the Goldstone modes in the density channel exhibit anisotropic overdamping. The Goldstone modes in the spin channel have nearly isotropic underdamped dispersion relation at small propagating wavevectors. Due to the coupling to the Goldstone modes, the spin wave spectrum develops resonance peaks in both the {alpha} and {beta}-phases, which can be detected in inelastic neutron scattering experiments. In the p-wave channel {beta}-phase, a chiral ground state inhomogeneity is spontaneously generated due to a Lifshitz-like instability in the originally nonchiral systems. Possible experiments to detect these phases are discussed.

Wu, Congjun; /Santa Barbara, KITP; Sun, Kai; Fradkin, Eduardo; /Illinois U., Urbana; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

2010-03-16T23:59:59.000Z

254

Beam Dynamics and Instabilities in ELIC Design  

Science Conference Proceedings (OSTI)

In this paper, we report the first study of beam related instabilities in lepton ring of the proposed electron-ion collider beyond the 12 GeV upgrade of CEBAF at Jefferson lab. The design parameters are consistent with PEP-II. Present studies reveal that coupled bunch and two stream instabilities are important issues and we need feedback system. The Medium Energy Electron Ion Collider (MEIC) at Jefferson Lab has been envisioned as future high energy particle accelerator beyond the 12 GeV upgrade of CEBAF. The MEIC will consist of the existing polarized electron source complex with 12 GeV upgrade and a new ion complex with polarized and unpolarized light to medium ions. The conceptual layout is shown in Fig. 1 and the basic parameters in comparison with the similar machines are discussed in Table 1. The maximum permissible collision frequency at 1.5 GHz is dictated by the existing electron machine, allowing the relatively small charge per bunch and large crossing angle resulting in the increased beam stability and high luminosity. In this paper, we present the preliminary study of collective effects for e-ring.

S. Ahmed,B. Yunn,G. Krafft

2011-09-01T23:59:59.000Z

255

Investigation of global Alfven instabilities in TFTR  

Science Conference Proceedings (OSTI)

Toroidal Alfven Eigenmodes (TAE) were excited by the energetic neutral beam ions tangentially injected into TFTR plasmas at low magnetic field such that the injection velocities were comparable to the Alfven speed. The modes were identified by measurements from Mirnov coils and beam emission spectroscopy (BES). TAE modes appear in bursts whose repetition rate increases with beam power. The neutron emission rate exhibits sawtooth-like behavior and the crashes always coincide with TAE bursts. This indicates ejection of fast ions from the plasma until these modes are stabilized. The dynamics of growth and stabilization was investigated at various plasma current and magnetic field. The results indicate that the instability can effectively clamp the number of energetic ions in the plasma. The observed instability threshold is discussed in the light of recent theories. In addition to these TAE modes, intermittent oscillations at three times the fundamental TAE frequency were observed by Mirnov coils, but no corresponding signal was found in BES. It appears that these high frequency oscillations do not have direct effect on the plasma neutron source strength.

Wong, K.L.; Paul, S.F.; Fredrickson, E.D.; Nazikian, R.; Park, H.K.; Bell, M.; Bretz, N.L.; Budny, R.; Cheng, C.Z.; Cohen, S.; Hammett, G.W.; Jobes, F.C.; Johnson, L.; Meade, D.M.; Medley, S.S.; Mueller, D.; Nagayama, Y.; Owens, D.K.; Synakowski, E.J. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Durst, R.; Fonck, R.J. [Wisconsin Univ., Madison, WI (United States); Roberts, D.R. [Texas Univ., Austin, TX (United States); Sabbagh, S. [Columbia Univ., New York, NY (United States)

1992-01-01T23:59:59.000Z

256

Genome Majority Vote (GMV), Version 0.x  

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

Genome Majority Vote (GMV), Version 0.x Genome Majority Vote (GMV), Version 0.x The pipeline runs PRODIGAL gene predictions on all genomes, runs pan-reciprocal BLAST, and...

257

The evolution of genome size in ants  

E-Print Network (OSTI)

for future whole-genome sequencing projects. Page 1 of 9 (genotyping to whole-genome sequencing [1-3]. The genomeconsideration for whole-genome sequencing programs, our

Tsutsui, Neil D; Suarez, Andrew V; Spagna, Joseph C; Johnston, J Spencer

2008-01-01T23:59:59.000Z

258

One Bacterial Cell, One Complete Genome  

E-Print Network (OSTI)

Bader JS, et al. (2005) Genome sequencing in microfabricatedDR (2006) Whole-genome re-sequencing. Curr Opin Genet DevSingle cell MDA and genome sequencing The yellow portion of

Woyke, Tanja

2010-01-01T23:59:59.000Z

259

Rearrangement Phylogeny of Genomes in Contig Form  

Science Conference Proceedings (OSTI)

There has been a trend in increasing phylogenetic coverage for genome sequencing while decreasing the sequencing coverage for each genome. With lower coverage, there is an increasing number of genomes being published in contig form. Rearrangement algorithms, ...

Adriana Muoz; David Sankoff

2009-04-01T23:59:59.000Z

260

Tissue sampling and standards for vertebrate genomics  

E-Print Network (OSTI)

and standards for vertebrate genomics. GigaScience 2012 1:8.transition to conservation genomics. TIG 2010, 26:177187.Siemens DH: Ecological genomicschanging perspectives on

2012-01-01T23:59:59.000Z

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


261

PLATCOM: a platform for computational comparative genomics  

E-Print Network (OSTI)

The exponential accumulation of genomic sequence data demands systematic analysis of genetic information and requires use of various computational approaches to handle such huge sets of genomic data. Comparative genomics,

Kwangmin Choi; Jeong-hyeon Choi; Amit Saple; Zhiping Wang; Jason Lee; Sun Kim

2005-01-01T23:59:59.000Z

262

Genome Halving by Block Interchange  

E-Print Network (OSTI)

We address the problem of finding the minimal number of block interchanges (exchange of two intervals) required to transform a duplicated linear genome into a tandem duplicated linear genome. We provide a formula for the distance as well as a polynomial time algorithm for the sorting problem.

Thomas, Antoine; Varr, Jean-Stphane

2011-01-01T23:59:59.000Z

263

Human Genome Research: Decoding DNA  

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

Human Genome Research: Decoding DNA Human Genome Research: Decoding DNA Resources with Additional Information Charles DeLisi As head of DOE's Office of Health and Environmental Research, Charles DeLisi played a pivotal role in proposing and initiating the Human Genome Program in 1986. The U.S. Department of Energy (DOE) has historically been active in supporting human genome research. On September 10, 2003, Secretary of Energy Spencer Abraham presented the Secretary's Gold Award to Aristides Patrinos and Francis Collins for their leadership of the government's Human Genome Project. At DOE's Office of Science, Dr. Patrinos is the Associate Director for Biological and Environmental Research. He has been a researcher at the department's Oak Ridge National Laboratory and Brookhaven National Laboratory.

264

Draft Genome Sequence  

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

Draft Draft Genome Sequence of Serratia sp. Strain ATCC 39006, a Model Bacterium for Analysis of the Biosynthesis and Regulation of Prodigiosin, a Carbapenem, and Gas Vesicles Peter C. Fineran, a Marina C. Iglesias Cans, a Joshua P. Ramsay, b Nabil M. Wilf, b Desiree Cossyleon, a Matthew B. McNeil, a Neil R. Williamson, b Rita E. Monson, b S. Anette Becher, c Jo-Ann L. Stanton, d Kim Brügger, e Steven D. Brown, f George P. C. Salmond b Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand a ; Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom b ; AgResearch Ltd., Invermay Agricultural Centre, Mosgiel, New Zealand c ; Department of Anatomy, University of Otago, Dunedin, New Zealand d ; EASIH, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom e ; Biosciences Division, Oak Ridge National Laboratory, Oak Ridge,

265

Yeast Ancestral Genome Reconstructions - CECM - Simon Fraser ...  

E-Print Network (OSTI)

on eukaryotic nuclear genomes are based on parsimony (some statistical methods have been used on mitochondrial or bacterial genomes, see Darling et al.

266

BMC Genomics BioMed Central  

E-Print Network (OSTI)

Research article What can you do with 0.1 genome coverage? A case study based on a genome survey of the scuttle fly Megaselia scalaris (Phoridae)

David A Rasmussen; Mohamed Af Noor

2009-01-01T23:59:59.000Z

267

JGI - Distinguished Postdoctoral Fellow in Genomics  

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

Distinguished Postdoctoral Fellow in Genomics The Department of Energy Joint Genome Institute (DOE JGI) in Walnut Creek, CA is soliciting Postdoctoral Fellows working in the...

268

Turbulence-Induced Instabilities in EP and QGP  

E-Print Network (OSTI)

Polarization properties of turbulent stochastically inhomogeneous ultrarelativistic QED plasma are studied. It is shown that the sign of nonlinear turbulent Landau damping corresponds to an instability of the spacelike modes and, for sufficiently large turbulent fields, to an actual instability of a system.

Martin Kirakosyan; Andrei Leonidov; Berndt Muller

2012-12-28T23:59:59.000Z

269

Computation of azimuthal combustion instabilities in an helicopter combustion chamber  

E-Print Network (OSTI)

Computation of azimuthal combustion instabilities in an helicopter combustion chamber C. Sensiau to compute azimuthal combustion instabilities is presented. It requires a thermoacoustic model using a n - formulation for the coupling between acoutics and combustion. The parameters n and are computed from a LES

Nicoud, Franck

270

Overview of nonlinear theory of kinetically driven instabilities  

Science Conference Proceedings (OSTI)

An overview is presented of the theory for the nonlinear behavior of instabilities driven by the resonant wave particle interaction. The approach should be applicable to a wide variety of kinetic systems in magnetic fusion devices and accelerators. Here the authors emphasize application to Alfven were driven instability, and the principles of the theory are used to interpret experimental data.

Berk, H.L.; Breizman, B.N.

1998-09-01T23:59:59.000Z

271

TAE SATURATION OF ALPHA PARTICLE DRIVEN INSTABILITY IN TFTR  

E-Print Network (OSTI)

TAE SATURATION OF ALPHA PARTICLE DRIVEN INSTABILITY IN TFTR N. N. Gorelenkovy, Y. Chen, R. B. White. In this paper we apply a recently developed nonlinear theory of kinetic instabilities [5] to calculate calculation had been added to allow an accurate numerical integration of Eq.(14) over the phase space

272

Solitary Alfven wave envelopes and the modulational instability  

SciTech Connect

The derivative nonlinear Schroedinger equation describes the modulational instability of circularly polarized dispersive Alfven wave envelopes. It also may be used to determine the properties of finite amplitude localized stationary wave envelopes. Such envelope solitons exist only in conditions of modulational stability. This leaves open the question of whether, and if so, how, the modulational instability produces envelope solitons. 12 refs.

Kennel, C.F.

1987-06-01T23:59:59.000Z

273

CLIMATE INSTABILITY ON TIDALLY LOCKED EXOPLANETS  

Science Conference Proceedings (OSTI)

Feedbacks that can destabilize the climates of synchronously rotating rocky planets may arise on planets with strong day-night surface temperature contrasts. Earth-like habitable planets maintain stable surface liquid water over geologic time. This requires equilibrium between the temperature-dependent rate of greenhouse-gas consumption by weathering, and greenhouse-gas resupply by other processes. Detected small-radius exoplanets, and anticipated M-dwarf habitable-zone rocky planets, are expected to be in synchronous rotation (tidally locked). In this paper, we investigate two hypothetical feedbacks that can destabilize climate on planets in synchronous rotation. (1) If small changes in pressure alter the temperature distribution across a planet's surface such that the weathering rate goes up when the pressure goes down, a runaway positive feedback occurs involving increasing weathering rate near the substellar point, decreasing pressure, and increasing substellar surface temperature. We call this feedback enhanced substellar weathering instability (ESWI). (2) When decreases in pressure increase the fraction of surface area above the melting point (through reduced advective cooling of the substellar point), and the corresponding increase in volume of liquid causes net dissolution of the atmosphere, a further decrease in pressure will occur. This substellar dissolution feedback can also cause a runaway climate shift. We use an idealized energy balance model to map out the conditions under which these instabilities may occur. In this simplified model, the weathering runaway can shrink the habitable zone and cause geologically rapid 10{sup 3}-fold atmospheric pressure shifts within the habitable zone. Mars may have undergone a weathering runaway in the past. Substellar dissolution is usually a negative feedback or weak positive feedback on changes in atmospheric pressure. It can only cause runaway changes for small, deep oceans and highly soluble atmospheric gases. Both instabilities are suppressed if the atmosphere has a high radiative efficiency. Our results are most relevant for atmospheres that are thin, have low greenhouse-gas radiative efficiency, and have a principal greenhouse gas that is also the main constituent of the atmosphere. ESWI also requires land near the substellar point, and tectonic resurfacing (volcanism, mountain-building) is needed for large jumps in pressure. These results identify a new pathway by which habitable-zone planets can undergo rapid climate shifts and become uninhabitable.

Kite, Edwin S.; Manga, Michael [Department of Earth and Planetary Science, University of California at Berkeley, CA 94720 (United States); Gaidos, Eric, E-mail: edwin.kite@gmail.com [Department of Geology and Geophysics, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

2011-12-10T23:59:59.000Z

274

Observation of Beam ION Instability in Spear3  

SciTech Connect

Weak vertical coupled bunch instability with oscillation amplitude at {mu}m level has been observed in SPEAR3. The instability becomes stronger when there is a vacuum pressure rise by partially turning off vacuum pumps and it becomes weaker when the vertical beam emittance is increased by turning off the skew quadrupole magnets. These confirmed that the instability was driven by ions in the vacuum. The threshold of the beam ion instability when running with a single bunch train is just under 200 mA. This paper presents the comprehensive observations of the beam ion instability in SPEAR3. The effects of vacuum pressure, beam current, beam filling pattern, chromaticity, beam emittance and bunch-by-bunch feedback are investigated in great detail. In an electron accelerator, ions generated from the residual gas molecules can be trapped by the beam. Then these trapped ions interact resonantly with the beam and cause beam instability and emittance blow-up. Most existing light sources use a long single bunch train filling pattern, followed by a long gap to avoid multi-turn ion trapping. However, such a gap does not preclude ions from accumulating during one passage of the single bunch train beam, and those ions can still cause a Fast Ion Instability (FII) as predicted by Raubenheimer and Zimmermann. FII has been observed in ALS, and PLS by artificially increasing the vacuum pressure by injecting helium gas into the vacuum chamber or by turning off the ion pumps in order to observe the beam ion instability. In some existing rings, for instance B factory, the beam ion instability was observed at the beginning of the machine operation after a long period of shutdown and then it automatically disappeared when the vacuum was better. However, when the beam emittance becomes smaller, the FII can occur at nominal conditions as observed in PLS, SOLEIL and SSRF. This paper reports the observations of beam ion instabilities in SPEAR3 under different condition during a period of one year, which includes single bunch train instability (FII) and multi-bunch train instability. Note that the instability may be not the same even with the same beam due to the change of the vacuum with time. SPEAR3 has a circumference of 234 m with a harmonic number of 372. SPEAR3 runs with six bunch train filling pattern in order to suppress the possible beam ion instability. Table 1 lists the main parameters of SPEAR3. The vacuum of SPEAR3 ranges from 0.1 to 0.5 nTorr, which varies from section to section.

Teytelman, D.; /Dimtel, Redwood City; Cai, Y.; Corbett, W.J.; Raubenheimer, T.O.; Safranek, J.A.; Schmerge, J.F.; Sebek, J.J.; Wang, L.; /SLAC

2011-12-14T23:59:59.000Z

275

Angle Instability Detection in Power Systems with High Wind Penetration  

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

Angle Instability Detection in Power Angle Instability Detection in Power Systems with High Wind Penetration Using PMUs YC Zhang National Renewable Energy Laboratory Yingchen.zhang@nrel.gov 27/28 June 2013 Washington, DC DOE/OE Transmission Reliability Program Angle Instability Detection in Power Systems with High Wind Penetration Using Synchrophasor Measurements  Project Objective * Utilize synchrophasor measurements to estimate the equivalent inertia of a power source such as synchronous generators or wind turbine generators * Develop angle instability detection method for a system with high wind penetration using the synchrophasor measurements 2 3 Background Submitted to IEEE Journal of Emerging and Selected Topics in Power Electronics * In case of angular instability, some machines will have

276

Plasma heating from alpha particle micro-instabilities  

Science Conference Proceedings (OSTI)

Potential use of thermonuclear (i.e., fusion product) driven kinetic instabilities to heat the background plasma has long been recognized. Considerable research on velocity space micro-instabilities exists. Most work to date has focused upon the basic physics criteria for and characteristics of particular micro-instabilities. Kinetic instabilities resulting in spatial transport of fusion products have also received some attention, but the effects on reactor concepts and performance remain uncertain. We have developed an engineering model which scopes the effect of a velocity space relaxation of fast alphas on a quasi-linear time scale. This model includes the additional heating to background plasma ions under the assumptions of: ion damping of the plasma wave; heating to background plasma results predominantly from fusion products; and periodic hiccups of the instability.

Miley, G.H.; Sutton, W.R.; Choi, C.K.

1981-01-01T23:59:59.000Z

277

Transverse instability analysis for the IPNS Upgrade  

SciTech Connect

The proposed 1-MW spallation neutron source upgrade calls for a 2-GeV rapidly-cycling synchrotron (RCS) with an intensity of 1.04{times}10{sup 14} protons per pulse. The potential exists for the excitation of collective, intensity-dependent transverse instabilities. These can normally be controlled by introducing a betatron tune shift or spread, where care is exercised to avoid single-particle resonance effects. Adjusting the chromaticity using sextupoles to vary the head-to-tail phase shift is compared to introducing Landau damping by octupoles. An option for a feedback system is also examined. The momentum spread used for the transverse analysis was obtained from the requirements for longitudinal stability.

Harkay, K.; Cho, Y.

1995-07-01T23:59:59.000Z

278

MIX and Instability Growth from Oblique Shock  

SciTech Connect

We have studied the formation and evolution of shock-induced mix resulting from interface features in a divergent cylindrical geometry. In this research a cylindrical core of high-explosive was detonated to create an oblique shock wave and accelerate the interface. The interfaces studied were between the high-explosive/aluminum, aluminum/plastic, and finally plastic/air. Pre-emplaced surface features added to the aluminum were used to modify this interface. Time sequence radiographic imaging quantified the resulting instability formation from the growth phase to over 60 {micro}s post-detonation. Thus allowing the study of the onset of mix and evolution to turbulence. The plastic used here was porous polyethylene. Radiographic image data are compared with numerical simulations of the experiments.

Molitoris, J D; Batteux, J D; Garza, R G; Tringe, J W; Souers, P C; Forbes, J W

2011-07-22T23:59:59.000Z

279

Chromosomal instability determines taxane sensitivity - supplementary materials  

E-Print Network (OSTI)

n D ise as e? fre e S urv ivin g CIN_survival_genes=Expression CIN_survival_genes=Suppression HR = 0.44 (0.20 ? 0.97) logrank P = 0.037 5 Reference [1] Carter SL, Eklund AC, Kohane IS, Harris LN, Szallasi Z. A signature of chromosomal instability... GU 57 25 III ductal sinister 0/2 JD07 aGS 63 30 II ductal sinister 0/0 JD08 dGS 86 10 ND lobular sinister 0/0 JD09 dGS 61 ND II ductal sinister 0/0 JD10_33 aGU 85 45 III comedo dexter 0/3 JD11 aGS 88 20 III ductal sinister 0/0 JD12 aGU 55 40 III ductal...

Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang; Howell, Michael; Ried, Thomas; Habermann, Jens K; Auer, Gert; Brenton, James D; Szallasi, Zoltan; Downward, Julian

2009-04-24T23:59:59.000Z

280

Violent Crime, Residential Instability and Mobility: Does the Relationship Differ in Minority Neighborhoods?  

E-Print Network (OSTI)

7 ORIGINAL PAPER Violent Crime, Residential Instability andrelationship between violent crime and residential stabilitythe instabilityviolent crime relationship. To test the

Boggess, Lyndsay N.; Hipp, John R.

2010-01-01T23:59:59.000Z

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


281

DOE Joint Genome Institute: Spikemoss Genome Offers New Paths...  

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

5, 2011 Spikemoss Genome Offers New Paths for Biofuels Research--Bridges Plant Development Gap WALNUT CREEK, Calif.- It's not quite Christmas, but the DNA sequence of a small plant...

282

Origins and consequences of radiation…induced centrosome aberrations  

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

Origins and consequences of radiation-induced centrosome aberrations Origins and consequences of radiation-induced centrosome aberrations Sangeetha Vijayakumar, Nisarg Shah, Ignacio Fernandez-Garcia, Mary Helen Barcellos-Hoff Department of Radiation Oncology, New York University School of Medicine, NY, NY. Centrosome aberrations are frequently observed in pre-neoplastic breast lesions and are known to drive chromosomal instability (Lingle et al., 2002). Previous studies from our lab have shown that human mammary epithelial cells exposed to low doses of radiation exhibit centrosome aberrations (CAs) in a dose dependent manner from 10-200 cGy (Maxwell et al., 2008). These data demonstrated that radiation-induced CAs actually precede and generate genomic instability and that TGFβ is a key mediator

283

Human genome. 1993 Program report  

SciTech Connect

The purpose of this report is to update the Human Genome 1991-92 Program Report and provide new information on the DOE genome program to researchers, program managers, other government agencies, and the interested public. This FY 1993 supplement includes abstracts of 60 new or renewed projects and listings of 112 continuing and 28 completed projects. These two reports, taken together, present the most complete published view of the DOE Human Genome Program through FY 1993. Research is progressing rapidly toward 15-year goals of mapping and sequencing the DNA of each of the 24 different human chromosomes.

Not Available

1994-03-01T23:59:59.000Z

284

Information entropy based methods for genome comparison  

Science Conference Proceedings (OSTI)

A plethora of biologically useful information lies obscured in the genomes of organisms. Encoded within the genome of an organism is the information about its evolutionary history. Evolutionary signals are scattered throughout the genome. Bioinformatics ... Keywords: clustering, genome comparison, segmentation, sequence alignment, shannon entropy

Mehul Jani; Rajeev K. Azad

2013-05-01T23:59:59.000Z

285

DOE Joint Genome Institute 2008 Progress Report  

E-Print Network (OSTI)

biofuel production. Diatom Genome Helps Explain Their Success in Capturing Carbon Diatoms, mighty microscopic algae,

Gilbert, David

2009-01-01T23:59:59.000Z

286

Genomic Aspects of Research Involving Polyploid Plants  

Science Conference Proceedings (OSTI)

Almost all extant plant species have spontaneously doubled their genomes at least once in their evolutionary histories, resulting in polyploidy which provided a rich genomic resource for evolutionary processes. Moreover, superior polyploid clones have been created during the process of crop domestication. Polyploid plants generated by evolutionary processes and/or crop domestication have been the intentional or serendipitous focus of research dealing with the dynamics and consequences of genome evolution. One of the new trends in genomics research is to create synthetic polyploid plants which provide materials for studying the initial genomic changes/responses immediately after polyploid formation. Polyploid plants are also used in functional genomics research to study gene expression in a complex genomic background. In this review, we summarize the recent progress in genomics research involving ancient, young, and synthetic polyploid plants, with a focus on genome size evolution, genomics diversity, genomic rearrangement, genetic and epigenetic changes in duplicated genes, gene discovery, and comparative genomics. Implications on plant sciences including evolution, functional genomics, and plant breeding are presented. It is anticipated that polyploids will be a regular subject of genomics research in the foreseeable future as the rapid advances in DNA sequencing technology create unprecedented opportunities for discovering and monitoring genomic and transcriptomic changes in polyploid plants. The fast accumulation of knowledge on polyploid formation, maintenance, and divergence at whole-genome and subgenome levels will not only help plant biologists understand how plants have evolved and diversified, but also assist plant breeders in designing new strategies for crop improvement.

Yang, Xiaohan [ORNL; Ye, Chuyu [ORNL; Tschaplinski, Timothy J [ORNL; Wullschleger, Stan D [ORNL; Tuskan, Gerald A [ORNL

2011-01-01T23:59:59.000Z

287

JGI - 2009 Genome Sequencing Targets  

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

July 2, 2008 July 2, 2008 Pine Tree, Boat-Boring Bivalve "Bugs", Duck Weed, Oil-Producing Microalgae, Stinkbird Gut, 40 Others Top DOE Joint Genome Institute 2009 Genome Sequencing Targets WALNUT CREEK, CA-In the continuing effort to tap the vast, unexplored reaches of the earth's microbial and plant domains for bioenergy and environmental applications, the DOE Joint Genome Institute (DOE JGI) has announced its latest portfolio of DNA sequencing projects that it will undertake in the coming year. The 44 projects, culled from nearly 150 proposals received through the Community Sequencing Program (CSP), represent over 60 billion nucleotides of data to be generated through this biodiversity sampling campaign-roughly the equivalent of 20 human genomes. "The scientific and technological advances enabled by the information

288

Synthetic Genomics: Options for Governance  

E-Print Network (OSTI)

Gene and genome synthesis, that is, constructing long stretches of DNA from constituent chemicals, provides scientists with new and unparalleled capabilities both for understanding biology and for using it for beneficial ...

Garfinkel, Michele

2007-10-17T23:59:59.000Z

289

Annotation-based genome-wide SNP discovery in the large and complex Aegilops tauschii genome using next-generation sequencing without a reference genome sequence  

E-Print Network (OSTI)

and physical maps, genome sequencing, marker-assistedof scaffolds during genome sequencing. To use RJs in SNPallows for deep genome coverage sequencing, a prerequisite

2011-01-01T23:59:59.000Z

290

Prediction of core saturation instability at an HVDC converter  

SciTech Connect

Core saturation instability has occurred on several HVDC schemes resulting from interactions between second harmonic and dc quantities (voltages and currents) on the ac side of the converter and fundamental frequency quantities on the dc side of the converter. The instability can be reinforced by unbalanced saturation of the converter transformers. The paper presents an analytical method which can be used to quickly screen ac and dc system operating conditions to predict where core saturation instability is likely to occur. Analytical results have been confirmed using the digital transients simulation program PSCAD/EMTDC.

Burton, R.S. [Teshmont Consultants, Inc., Winnipeg, Manitoba (Canada); Fuchshuber, C.F. [Alberta Power Ltd., Edmonton, Alberta (Canada); Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada); Gole, A.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)

1996-10-01T23:59:59.000Z

291

Dust-induced instability in a rotating plasma  

SciTech Connect

The effect of immobile dust on stability of a magnetized rotating plasma is analyzed. In the presence of dust, a term containing an electric field appears in the one-fluid equation of plasma motion. This electric field leads to an instability of the magnetized rotating plasma called the dust-induced rotational instability (DRI). The DRI is related to the charge imbalance between plasma ions and electrons introduced by the presence of charged dust. In contrast to the well-known magnetorotational instability requiring the decreasing radial profile of the plasma rotation frequency, the DRI can appear for an increasing rotation frequency profile.

Mikhailovskii, A. B.; Vladimirov, S. V.; Lominadze, J. G.; Tsypin, V. S.; Churikov, A. P.; Erokhin, N. N.; Galvao, R. M. O. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); School of Physics, University of Sydney, Sydney, N.S.W. 2006 (Australia); Kharadze Abastumani National Astrophysical Observatory, 2a, Kazbegi Ave., Tbilisi 0160 (Georgia); Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil); Syzran Branch of Samara Technical University, 45, Sovetskaya Str., Syzran, Samara Region 446001 (Russian Federation); Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); Physics Institute, University of Sao Paulo, Cidade Universitaria, 05508-900, Sao Paulo, Brazil and Brazilian Center for Physics Research, Rua Xavier Sigaud, 150, 22290-180, Rio de Janeiro (Brazil)

2008-01-15T23:59:59.000Z

292

Estimation of collective instabilities in RHIC  

Science Conference Proceedings (OSTI)

The authors have estimated the broadband impedance in RHIC to be {vert_bar}Z/n{vert_bar} < 1.2 {Omega} for frequencies above 100 MHz. The Z/n threshold is set for Au{sup +79} ions at transition with an estimated 10% growth in emittance for Z/n = 1.5 {Omega}. They summarize the sources of broad and narrow band impedances in RHIC and investigate the multibunch instability limits throughout the machine cycle. The largest contribution to the broadband impedance comes from the abort and injection kickers. Since RHIC is designed to accelerate fully stripped ions from H{sup +} up to Au{sup +79} they give results for both protons and gold ions; other ions should give results somewhere between these two extremes. All ion species are expected to be stable during storage. At lower energies damping systems and chromaticity corrections will limit any growth to acceptable levels during the short time it takes to inject and accelerate the beams.

MacKay, W.W.; Blaskiewicz, M.; Deng, D.; Mane, V.; Peggs, S.; Ratti, A.; Rose, J.; Shea, T.J.; Wei, J.

1995-05-01T23:59:59.000Z

293

Thermal instability in the collisionally cooled gas  

E-Print Network (OSTI)

We have presented the non-equilibrium (time-dependent) cooling rate and ionization state calculations for a gas behind shock waves with $v \\sim 50-150$ km s$^{-1}$ ($T_s \\sim 0.5 - 6\\times 10^5$ K). Such shock waves do not lead to the radiative precursor formation, i.e. the thermal evolution of a gas behind the shock waves are controlled by collisions only. We have found that the cooling rate in a gas behind the shock waves with $v \\sim 50-120$ km s$^{-1}$ ($T_s \\sim 0.5 - 3\\times 10^5$ K) differs considerably from the cooling rate for a gas cooled from $T = 10^8$ K. It is well-known that a gas cooled from $T = 10^8$ K is thermally unstable for isobaric and isochoric perturbations at $T \\simgt 2\\times 10^4$ K. We have studied the thermal instability in a collisionally controlled gas for shock waves with $v \\sim 50-150$ km s$^{-1}$. We have found that the temperature range, where the postshock gas is thermally unstable, is significantly modified and depends on both gas metallicity and ionic composition of a ga...

Vasiliev, Evgenii O

2011-01-01T23:59:59.000Z

294

Electrostatic 'bounce' instability in a magnetotail configuration  

SciTech Connect

To understand the possible destabilization of two-dimensional current sheets, a kinetic model is proposed to describe the resonant interaction between electrostatic modes and trapped particles that bounce within the sheet. This work follows the initial investigation by Tur et al.[Phys. Plasmas 17, 102905 (2010)] that is revised and extended. Using a quasi-parabolic equilibrium state, the linearized gyro-kinetic Vlasov equation is solved for electrostatic fluctuations with period of the order of the electron bounce period. Using an appropriated Fourier expansion of the particle motion along the magnetic field, the complete time integration of the non-local perturbed distribution functions is performed. The dispersion relation for electrostatic modes is then obtained through the quasineutrality condition. It is found that strongly unstable electrostatic modes may develop provided that the current sheet is moderately stretched and, more important, that the proportion of passing particle remains small (less than typically 10%). This strong but finely tuned instability may offer opportunities to explain features of magnetospheric substorms.

Fruit, G.; Louarn, P.; Tur, A. [Institut de Recherche en Astrophysique et Planetologie (IRAP), Toulouse Universite de Toulouse, CNRS UMR5277, Toulouse (France)

2013-02-15T23:59:59.000Z

295

Moist Absolute Instability: The Sixth Static Stability State  

Science Conference Proceedings (OSTI)

It is argued that a sixth static stability state, moist absolute instability, can be created and maintained over mesoscale areas of the atmosphere. Examination of over 130 000 soundings and a numerical simulation of an observed event are employed ...

George H. Bryan; Michael J. Fritsch

2000-06-01T23:59:59.000Z

296

Linear Baroclinic instability with the Geostrophic Momentum Approximation  

Science Conference Proceedings (OSTI)

The linear Eady model of baroclinic instability with the geostrophic momentum (GM) approximation is solved analytically in physical space and shown to be identical to linear three-dimensional semigeostrophic theory. Both the growth rates and the ...

Peter R. Bannon

1989-02-01T23:59:59.000Z

297

Radiative signatures of the relativistic Kelvin-Helmholtz instability  

Science Conference Proceedings (OSTI)

We present a particle-in-cell simulation of the relativistic Kelvin-Helmholtz Instability (KHI) that for the first time delivers angularly resolved radiation spectra of the particle dynamics during the formation of the KHI. This enables studying the ...

M. Bussmann, H. Burau, T. E. Cowan, A. Debus, A. Huebl, G. Juckeland, T. Kluge, W. E. Nagel, R. Pausch, F. Schmitt, U. Schramm, J. Schuchart, R. Widera

2013-11-01T23:59:59.000Z

298

Investigation of thermal filamentation instability over Gakona, Alaska  

E-Print Network (OSTI)

The thermal filamentation instability has been invoked to explain the formation of parallel plate waveguides in mid-latitude ionospheric plasmas during Arecibo, Puerto Rico heating experiments in 1997. The geometry of the ...

Cohen, Joel (Joel A.), S.B. Massachusetts Institute of Technology

2007-01-01T23:59:59.000Z

299

Liquid-gas instability and superfluidity in nuclear matter  

E-Print Network (OSTI)

We study effects of the medium polarization on superfluidity in symmetric nuclear matter in a relativistic formalism. An effect of the liquid-gas instability is emphasized. We examine two types of decomposition of the nucleon propagator; the standard Feynman-density and the particle-hole-antiparticle ones. In both cases, the medium polarization effect is determined by a characteristic cancellation among the \\sigma, the longitudinal \\omega, and the \\sigma-\\omega mixed polarizations. The instability leads to increase of pairing gap. Around the saturation density that is free from the instability the medium polarization enhances pairing gap in the former case whereas reduces in the latter. At the lowest density that is also free from the instability the gap increases in both cases.

Masayuki Matsuzaki

2006-03-23T23:59:59.000Z

300

BaroclinicBarotropic Instabilities of the Gulf Stream Extension  

Science Conference Proceedings (OSTI)

In this paper, the baroclinic-barotropic instability of the Gulf Stream is studied numerically. The quasigeo-strophic potential vorticity equation is linearized around the mean flow, which is modeled using data from field measurements in the Gulf ...

A. A. Dimas; G. S. Triantafyllou

1995-05-01T23:59:59.000Z

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


301

The Slope of Moist Symmetric Instability with Water Loading  

Science Conference Proceedings (OSTI)

Idealized numerical experiments, supported by analytic considerations, are performed to determine the preferred direction of symmetric instability when water loading is considered. It is concluded that the most unstable direction is tangent to a ...

Maurizio Fantini; Piero Malguzzi

2008-09-01T23:59:59.000Z

302

Rotational suppression of the Tayler instability in stellar radiation zones  

E-Print Network (OSTI)

The study of the magnetic field in stellar radiation zones is an important topic in modern astrophysics because the magnetic field can play an important role in several transport phenomena such as mixing and angular momentum transport. We consider the influence of rotation on stability of a predominantly toroidal magnetic field in the radiation zone. We find that the effect of rotation on the stability depends on the magnetic configuration of the basic state. If the toroidal field increases sufficiently rapidly with the spherical radius, the instability cannot be suppressed entirely even by a very fast rotation although the strength of the instability can be significantly reduced. On the other hand, if the field increases slowly enough with the radius or decreases, the instability has a threshold and can be completely suppressed in rapidly rotating stars. We find that in the regions where the instability is entirely suppressed a particular type of magnetohydrodynamic waves may exist which are marginally stabl...

Bonanno, Alfio

2013-01-01T23:59:59.000Z

303

Quark-Gluon Plasma Thermalization and Plasma Instabilities  

E-Print Network (OSTI)

In this talk, I review the important role played by plasma instabilities in the thermalization of quark-gluon plasmas at very high energy. [Conference talk presented at Strong and Electroweak Mattter 2004, Helsinki, Finland, June 16--19.

Peter Arnold

2004-08-31T23:59:59.000Z

304

Kink instability suppression with stochastic cooling pickup and kicker  

Science Conference Proceedings (OSTI)

The kink instability is one of the major beam dynamics issues of the linac-ring based electron ion collider. This head-tail type instability arises from the oscillation of the electron beam inside the opposing ion beam. It must be suppressed to achieve the desired luminosity. There are various ways to suppress the instability, such as tuning the chromaticity in the ion ring or by a dedicated feedback system of the electron beam position at IP, etc. However, each method has its own limitation. In this paper, we will discuss an alternative opportunity of suppressing the kink instability of the proposed eRHIC at BNL using the existing pickup-kicker system of the stochastic cooling system in RHIC.

Hao Y.; Blaskiewicz, M.; Litvinenko, V.N.; Ptitsyn, V.

2012-05-20T23:59:59.000Z

305

Numerical Simulation of Atmospheric Response to Pacific Tropical Instability Waves  

Science Conference Proceedings (OSTI)

Tropical instability waves (TIWs) are 1000-km-long waves that appear along the sea surface temperature (SST) front of the equatorial cold tongue in the eastern Pacific. The study investigates the atmospheric planetary boundary layer (PBL) ...

R. Justin Small; Shang-Ping Xie; Yuqing Wang

2003-11-01T23:59:59.000Z

306

Nonseparable Baroclinic Instability. Part II: Primitive-Equations Dynamics  

Science Conference Proceedings (OSTI)

The problem of the origin of midlatitude cyclonic disturbances having characteristic spatial scales of 1000 km or less has remained outstanding for most of this century. Although the theory of baroclinic instability of Charney and Eady has often ...

G. W. Kent Moore; W. R. Peltier

1990-05-01T23:59:59.000Z

307

Negative-mass Instability in Nonlinear Plasma Waves  

SciTech Connect

The negative-mass instability (NMI), previously found in ion traps, appears as a distinct regime of the sideband instability in nonlinear plasma waves with trapped particles. As the bounce frequency of these particles decreases with the bounce action, bunching can occur if the action distribution is inverted in trapping islands. In contrast to existing theories that also infer instabilities from the anharmonicity of bounce oscillations, spatial periodicity of the islands turns out to be unimportant, and the particle distribution can be unstable even if it is at at the resonance. An analytical model is proposed which describes both single traps and periodic nonlinear waves and concisely generalizes the conventional description of the sideband instability in plasma waves. The theoretical results are supported by particle-in-cell simulations carried out for a regime accentuating the NMI effect.

I.Y. Dodin, P.F. Schmit, J. Rocks and N.J. Fisch

2013-01-30T23:59:59.000Z

308

A Numerical Study of Two-Dimensional Moist Baroclinic Instability  

Science Conference Proceedings (OSTI)

A study of baroclinic instability in the presence of moisture is performed with a primitive equation nonhydrostatic two-dimensional numerical model. A new assumption regarding the meridional structure of the perturbation mixing ratio is discussed ...

Maurizio Fantini

1993-05-01T23:59:59.000Z

309

Long-Term Observations of Tropical Instability Waves  

Science Conference Proceedings (OSTI)

Reynolds sea surface temperature (SST) data showing tropical instability waves (TIWs) in the tropical Pacific are analyzed along with current measurements from the Tropical AtmosphereOcean (TAO) buoy array and wind speeds from the European ...

Robert F. Contreras

2002-09-01T23:59:59.000Z

310

Filamentation instability of lower hybrid waves in a plasma  

SciTech Connect

It is shown that a strong lower hybrid wave is modulationally unstable to perturbations propagating along its own wave vector. The instability relies critically on the finite thermal corrections to the lower hybrid dispersion relation. (auth)

Kaw, P. K.

1976-02-01T23:59:59.000Z

311

A New Frontal Instability: Theory and ERICA Observations  

Science Conference Proceedings (OSTI)

A short-wave instability theory is applied to secondary waves on a narrow cold-front rainband observed during the Experiment on Rapidly Intensifying Cyclones over the Atlantic (ERICA). The basic mean state is approximated by the parabolic, ...

Nathan Paldor; Ching-Hwang Liu; Michael Ghil; Roger M. Wakimoto

1994-11-01T23:59:59.000Z

312

Mesoscale Circulation Growth under Conditions of Weak Inertial Instability  

Science Conference Proceedings (OSTI)

The hypothesis that inertial instability plays a role in the upscale development of mesoscale convective systems (MCSs) is explored by sampling environments that supported the growth of MCSs in the Preliminary Regional Experiment for STORM (...

David O. Blanchard; William R. Cotton; John M. Brown

1998-01-01T23:59:59.000Z

313

Local and Global Baroclinic Instability of Zonally Varying Flow  

Science Conference Proceedings (OSTI)

The baroclinic instability characteristics of zonally inhomogeneous basic states are examined with the intent of clarifying the factors governing the regional distribution of cyclogenesis. The vertical shear of the basic state wind is allowed to ...

R. T. Pierrehumbert

1984-07-01T23:59:59.000Z

314

Magnetorotational instability in plasmas with mobile dust grains  

SciTech Connect

The magnetorotational instability of dusty plasmas is investigated using the multi-fluid model and the general dispersion relation is derived based on local approximation. The dust grains are found to play an important role in the dispersion relation in the low-frequency mode and exhibit destabilizing effects on the plasma. Both the instability criterion and growth rate are affected significantly by the dust and when the dust is heavy enough to be unperturbed, the reduced dispersion relations are obtained. The instability criteria show that the dust grains have stabilizing effects on the instability when the rotation frequency decreases outwards and conversely lead to destabilizing effects when the rotation frequency increases outwards. The results are relevant to accession and protoplanetary disks.

Ren Haijun [CAS Key Laboratory of Basic Plasma Physics, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Cao Jintao [Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Li Ding [CAS Key Laboratory of Basic Plasma Physics, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2013-03-15T23:59:59.000Z

315

Suppression of Baroclinic Instability in Horizontally Sheared Flows  

Science Conference Proceedings (OSTI)

Baroclinic instability in the presence of a meridionally sheared barotropic component to the basic flow is studied using a two-level model. The inclusion of a linear shear results in merldionally confined normal modes with growth rates much ...

I. N. James

1987-12-01T23:59:59.000Z

316

Slow Instabilities in Tropical Ocean BasinGlobal Atmosphere Models  

Science Conference Proceedings (OSTI)

The effect of ocean boundaries on instability in coupled ocean-natmosphere models is determined. Eigenvalues and eigenvectors are calculated for coupled systems featuring an ocean basin bounded zonally by a flat continent. The atmosphere is ...

Anthony C. Hirst

1988-03-01T23:59:59.000Z

317

Finescale Instabilities of the Double-Diffusive Shear Flow  

Science Conference Proceedings (OSTI)

This study examines dynamics of finescale instabilities in thermohalineshear flows. It is shown that the presence of the background diapycnal temperature and salinity fluxes due to double diffusion has a destabilizing effect on the basic ...

Timour Radko; Melvin E. Stern

2011-03-01T23:59:59.000Z

318

Instability Analysis of Terrain-Induced Canopy Flows  

Science Conference Proceedings (OSTI)

Tall vegetation and complex terrain create difficult conditions for measuring and modeling net ecosystematmosphere exchanges of carbon, water vapor, and pollutants. The instability of canopy flow regimes over complex terrain is critical for ...

Chuixiang Yi

2009-07-01T23:59:59.000Z

319

Divergent Barotropic Instability of the Tropical Asymmetric Easterly Jet  

Science Conference Proceedings (OSTI)

The divergent barotropic instability of a zonally averaged, observed, tropical, upper tropospheric, monsoon easterly jet is investigated by numerical integration of a linear spectral model. The Rossby radius of deformation for the upper ...

S. K. Mishra; D. Subrahmanyam; M. K. Tandon

1981-10-01T23:59:59.000Z

320

Recalculated Radiating Instabilities Using the Correct Matching and Boundary Conditions  

Science Conference Proceedings (OSTI)

Yun et al. (hereafter YPM) have reported results of a study on the radiating instabilities of nonzonal shear flows as a possible source of the energetic internal temperature fluctuations observed in the regions away from the axis of the Kuroshio ...

Jae-Yul Yun; James M. Price; Lorenz Magaard

2000-09-01T23:59:59.000Z

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


321

Parametric Subharmonic Instability of the Internal Tide at 29N  

Science Conference Proceedings (OSTI)

Observational evidence is presented for transfer of energy from the internal tide to near-inertial motions near 29N in the Pacific Ocean. The transfer is accomplished via parametric subharmonic instability (PSI), which involves interaction ...

J. A. MacKinnon; M. H. Alford; Oliver Sun; Rob Pinkel; Zhongxiang Zhao; Jody Klymak

2013-01-01T23:59:59.000Z

322

Implications of structural genomics target selection strategies: Pfam5000, whole genome, and random approaches  

E-Print Network (OSTI)

SK, Bonanno JB. Structural genomics. Methods Biochem AnalMizuguchi K. Structural genomics: an overview. Prog BiophysSE. A tour of structural genomics. Nat Rev Genet 2001;2(10):

Chandonia, John-Marc; Brenner, Steven E.

2004-01-01T23:59:59.000Z

323

Material instability hazards in mine-processing operations  

SciTech Connect

Many accidents occur in the mining industry as a result of the instability of material during handling and processing operation. Accidents due to dump point instability at stockpiles, and at spoil or waste piles, for example, occur with alarming frequency. Miners must be trained to be better aware of these hazards. Information on safe working procedures at stockpiles and surge piles is provided. Mine operators must review their training and operating procedures regularly to ensure that hazardous conditions are avoided.

Fredland, J.W.; Wu, K.K.; Kirkwood, D.W.

1993-10-01T23:59:59.000Z

324

Microtearing Instabilities and Electron Transport in the NSTX Spherical Tokamak  

SciTech Connect

We report a successful quantitative account of the experimentally determined electron thermal conductivity ?e in a beam-heated H mode plasma by the magnetic fluctuations from microtearing instabilities. The calculated ?e based on existing nonlinear theory agrees with the result from transport analysis of the experimental data. Without using any adjustable parameter, the good agreement spans the entire region where there is a steep electron temperature gradient to drive the instability.

K.L. Wong, S. Kaye, D.R. Mikkelsen, J.A. Krommes, K. Hill, R. Bell, and B. LeBlanc

2007-10-01T23:59:59.000Z

325

DOE Joint Genome Institute: Unraveling the Threads: Simplest cotton genome  

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

December 19, 2012 December 19, 2012 Unraveling the Threads: Simplest cotton genome offers clues for fiber improvements From the stockings decorating mantles to the new outfits in display windows calling to shoppers, cotton is woven into the fabric of the holiday season. For bioenergy researchers, however, fiber composition matters more than color and texture as each cotton strand is composed of more than two dozen coils of cellulose, a target biomass for next-generation biofuels. In the December 20, 2012 edition of Nature, an international consortium of researchers from 31 institutions including a team from the U.S. Department of Energy Joint Genome Institute (DOE JGI) present a high-quality draft assembly of the simplest cotton (Gossypium raimondii) genome. Additionally,

326

DOE Joint Genome Institute Completes Soybean Genome- Data Released to  

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

Press Release: December 8, 2008 Press Release: December 8, 2008 DOE Joint Genome Institute Completes Soybean Genome- Data Released to Advance Biofuel, Food, & Feed Research WALNUT CREEK, CA- The U.S. Department of Energy Joint Genome Institute (DOE JGI) has released a complete draft assembly of the soybean (Glycine max) genetic code, making it widely available to the research community to advance new breeding strategies for one of the world's most valuable plant commodities. Soybean not only accounts for 70 percent of the world's edible protein, but also is an emerging feedstock for biodiesel production. Soybean is second only to corn as an agricultural commodity and is the leading U.S. agricultural export. DOE JGI's interest in sequencing the soybean centers on its use for biodiesel, a renewable, alternative fuel with the highest energy content of

327

DOE Joint Genome Institute: Soybean Genome Analysis Reveals Pathways for  

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

January 13, 2010 January 13, 2010 Soybean Genome Analysis Reveals Pathways for Improving Biodiesel, Disease Resistance, and Reducing Waste Runoff WALNUT CREEK, CA-Soybean, one of the most important global sources of protein and oil, is now the first legume species with a published complete draft genome sequence. The sequence and its analysis appear in the January 14 edition of the journal Nature. The research team comprised 18 institutions, including the U.S. Department of Energy Joint Genome Institute (DOE JGI), the U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), Purdue University and the University of North Carolina at Charlotte. The DOE, National Science Foundation, USDA and United Soybean Board supported the research. helix made of soybeans

328

DOE Joint Genome Institute: New Genomic Model Defines Microbes by  

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

September 8, 2009 September 8, 2009 New Genomic Model Defines Microbes by Diet-Provides Tool for Tracking Environmental Change WALNUT CREEK, CA-In line with the U.S. Department of Energy (DOE) interest in characterizing the biotic factors involved in global carbon cycling, the DOE Joint Genome Institute (JGI) characterizes a diverse array of plants, microorganisms, and the communities in which they reside to inform options for reducing and stabilizing atmospheric greenhouse gases. Through a novel genomic approach detailed in the September 7 online edition and on the cover September 14 of the journal Proceedings of the National Academy of Sciences, an international team of scientists led by the University of New South Wales and the DOE JGI demonstrates how the microbial diversity of the oceans can be analyzed without necessarily

329

Stratorotational instability in MHD Taylor-Couette flows  

E-Print Network (OSTI)

The stability of dissipative Taylor-Couette flows with an axial stable density stratification and a prescribed azimuthal magnetic field is considered. Global nonaxisymmetric solutions of the linearized MHD equations with toroidal magnetic field, axial density stratification and differential rotation are found for both insulating and conducting cylinder walls. Flat rotation laws such as the quasi-Kepler law are unstable against the nonaxisymmetric stratorotational instability (SRI). The influence of a current-free toroidal magnetic field depends on the magnetic Prandtl number Pm: SRI is supported by Pm > 1 and it is suppressed by Pm \\lsim 1. For too flat rotation laws a smooth transition exists to the instability which the toroidal magnetic field produces in combination with the differential rotation. This nonaxisymmetric azimuthal magnetorotational instability (AMRI) has been computed under the presence of an axial density gradient. If the magnetic field between the cylinders is not current-free then also the Tayler instability occurs and the transition from the hydrodynamic SRI to the magnetic Tayler instability proves to be rather complex. Most spectacular is the `ballooning' of the stability domain by the density stratification: already a rather small rotation stabilizes magnetic fields against the Tayler instability. An azimuthal component of the resulting electromotive force only exists for density-stratified flows. The related alpha-effect for magnetic SRI of Kepler rotation appears to be positive for negative d\\rho/dz <0.

G. Ruediger; D. A. Shalybkov

2008-08-05T23:59:59.000Z

330

Human Genome Education Program  

Science Conference Proceedings (OSTI)

The funds from the DOE Human Genome Program, for the project period 2/1/96 through 1/31/98, have provided major support for the curriculum development and field testing efforts for two high school level instructional units: Unit 1, ''Exploring Genetic Conditions: Genes, Culture and Choices''; and Unit 2, ''DNA Snapshots: Peaking at Your DNA''. In the original proposal, they requested DOE support for the partial salary and benefits of a Field Test Coordinator position to: (1) complete the field testing and revision of two high school curriculum units, and (2) initiate the education of teachers using these units. During the project period of this two-year DOE grant, a part-time Field-Test Coordinator was hired (Ms. Geraldine Horsma) and significant progress has been made in both of the original proposal objectives. Field testing for Unit 1 has occurred in over 12 schools (local and non-local sites with diverse student populations). Field testing for Unit 2 has occurred in over 15 schools (local and non-local sites) and will continue in 12-15 schools during the 96-97 school year. For both curricula, field-test sites and site teachers were selected for their interest in genetics education and in hands-on science education. Many of the site teachers had no previous experience with HGEP or the unit under development. Both of these first-year biology curriculum units, which contain genetics, biotechnology, societal, ethical and cultural issues related to HGP, are being implemented in many local and non-local schools (SF Bay Area, Southern California, Nebraska, Hawaii, and Texas) and in programs for teachers. These units will reach over 10,000 students in the SF Bay Area and continues to receive support from local corporate and private philanthropic organizations. Although HGEP unit development is nearing completion for both units, data is still being gathered and analyzed on unit effectiveness and student learning. The final field testing result from this analysis will contribute to the final revisions of each unit during the second-year of this grant.

Richard Myers; Lane Conn

2000-05-01T23:59:59.000Z

331

Genomics.energy.gov--genome programs of the U.S. Department of...  

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

in environmental-waste cleanup, energy production, carbon cycling, and biotechnology. Genomics Image Gallery Visit this site for free downloadable, high-resolution, genomics...

332

Joint Genome Institute Progress Report 2002-2005  

E-Print Network (OSTI)

S, et al. Comparative genome sequencing of DrosophilaInternational Human Genome Sequencing Consortium. FinishingWhile NIH-funded genome sequencing activities largely

Gilbert, David

2005-01-01T23:59:59.000Z

333

Contribution of mobile genetic elements to Desulfovibrio vulgaris genome plasticity  

E-Print Network (OSTI)

management of the genome sequencing. References Altschul,species revealed the core genome, sequencing of 12 isolatesrevealed by ongoing genome sequencing projects. Although

Walker, C.B.

2010-01-01T23:59:59.000Z

334

Genomics, Gene Expression and Other Studies in Soybean Rust  

E-Print Network (OSTI)

by Christine Stone GENOME SEQUENCING PROJECT PhakopsoraUS DOE Joint Genome Institute DNA sequencing process LibraryUS DOE Joint Genome Institute DNA sequencing process Rolling

Posada-Buitrago, Martha Lucia

2005-01-01T23:59:59.000Z

335

Genome Project Standards in a New Era of Sequencing  

E-Print Network (OSTI)

for clone- based human genome sequencing, this finishing20850,USA HumanGenomeSequencingCenter,BaylorCollegeUSA HudsonAlphaGenomeSequencingCenter,HudsonAlpha

Hostetler, J.

2010-01-01T23:59:59.000Z

336

Complete genome sequence of Desulfomicrobium baculatum type strain (XT)  

E-Print Network (OSTI)

is deposited in Genome sequencing and annotation Genomeof Life, GEBA Table 2. Genome sequencing project informationand DNA isolation Genome sequencing and assembly tions to

Copeland, Alex

2010-01-01T23:59:59.000Z

337

Genomic Sequencing of Single Microbial Cells from Environmental Samples  

E-Print Network (OSTI)

as function of the genome sequencing effort. AdditionalYJ, Chen Z, et al. : Genome sequencing in microfabricatedof whole genome amplification and sequencing. Mechanical

Ishoey, Thomas

2010-01-01T23:59:59.000Z

338

Genomic analysis of high pressure adaptation in deep sea bacteria  

E-Print Network (OSTI)

This makes the genome sequencing project of Carnobacteriumpiezophile to undergo genome sequencing. Investigation intoMarine Microbial Genome Sequencing project. The initial

Stratton, Taylor Kristen

2008-01-01T23:59:59.000Z

339

Complete genome sequence of Acidimicrobium ferrooxidans type strain (ICPT)  

E-Print Network (OSTI)

with type strain genome sequencing projects registered inResearch, Braunschweig) Genome sequencing and annotationthe complete Table 2. Genome sequencing project information

Clum, Alicia

2010-01-01T23:59:59.000Z

340

Incorporating Genomics and Bioinformatics across the Life Sciences Curriculum  

E-Print Network (OSTI)

Page Incorporating Genomics and Bioinformatics across the2007) Discovering Genomics, Proteomics, and Bioinformatics,2003) Public access for teaching genomics, proteomics, and

Ditty, Jayna L.

2012-01-01T23:59:59.000Z

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


341

Genomes containing Duplicates are Hard to compare ... - CECM  

E-Print Network (OSTI)

and other genomic markers are common in genomes, due to several evolutionary . mechanisms, like gene duplication or whole genomes duplications [San01].

342

Dissection of Plant Defense Mechanisms Using Chemical and Molecular Genomics  

E-Print Network (OSTI)

of auxins by a chemical genomics approach." Journal ofadvances in chemical genomics." Current Medicinal Chemistrymolecular and chemical genomics." Phytopathology 97(7): S58-

Rodriguez-Salus, Melinda Sue

2012-01-01T23:59:59.000Z

343

Validation in Genomics: CpG Island Methylation Revisited  

E-Print Network (OSTI)

analysis. In: Functional Genomics: Methods and Protocols, M.Segal: Validation in Genomics: CpG Island Methylationpackage and applications to genomics. Bioinformatics and

Segal, Mark R

2006-01-01T23:59:59.000Z

344

Comparative genomics and evolution of eukaryotic phospholipid biosynthesis  

E-Print Network (OSTI)

S. Banfi and B. Franco, Genomics 55 (1999) 68-77. F. Simmer,Comparative genomics and evolution of eukaryoticwork utilizes comparative genomics and phylogenetics for

Lykidis, Athanasios

2006-01-01T23:59:59.000Z

345

Comparative genomics reveals diversity among xanthomonads infecting tomato and pepper  

E-Print Network (OSTI)

Potnis et al. : Comparative genomics reveals diversity amongtomato and pepper. BMC Genomics Submit your next manuscriptpv. syringae Potnis et al. BMC Genomics 2011, 12:146 http://

2011-01-01T23:59:59.000Z

346

Genomics of emerging infectious disease: A PLoS collection.  

E-Print Network (OSTI)

Origins and evolutionary genomics of the 2009 swine-originan Infectious Diseases Genomics Project predict and preventRavel J (2009) The role of genomics in the identification,

Eisen, Jonathan A; MacCallum, Catriona J

2009-01-01T23:59:59.000Z

347

TOPSAN: a collaborative annotation environment for structural genomics.  

E-Print Network (OSTI)

environment for structural genomics Dana Weekes 1 , S Srihigh-throughput structural genomics centers, despite theirbeing determined by structural genomics centers and high-

Weekes, Dana; Krishna, S; Bakolitsa, Constantina; Wilson, Ian A; Godzik, Adam; Wooley, John

2010-01-01T23:59:59.000Z

348

Application of Statistical Methods to Integrative Analysis of Genomic Data  

E-Print Network (OSTI)

in functional genomics . . . . . . . . . . . . . . . . . 1.3throughput technologies in genomics and proteomics promotesElizabeth A. Winzeler. Genomics, gene expression and DNA

Kim, Kyung Pil

2013-01-01T23:59:59.000Z

349

D.: Genome halving with an outgroup  

E-Print Network (OSTI)

Abstract: Some genomes are known to have incurred a genome doubling (tetraploidization) event in their evo lutionary history, and this is reflected today in patterns of duplicated segments scattered throughout their chromosomes. These duplications may be used as data to halve the genome, i.e. to reconstruct the an cestral genome at the moment of tetraploidization, but the solution is often highly non- unique. To resolve this problem, we adapt the genome halving algorithm of El-Mabrouk and Sankoff to take account of an external reference genome. We apply this to reconstruct the tetraploid ancestor of maize, using either rice or sorghum as the reference.

Chunfang Zheng; Qian Zhu; David Sankoff

2006-01-01T23:59:59.000Z

350

The Genomes On Line Database (GOLD) in 2007: status of genomic and metagenomic projects and their associated metadata  

E-Print Network (OSTI)

constantly monitoring genome sequencing projects worldwideas part of the Whole Genome Sequencing (WGS) project.large scale microbial genome sequencing programs have been

Liolios, Konstantinos

2008-01-01T23:59:59.000Z

351

The Genomes On Line Database (GOLD) in 2009: status of genomic and metagenomic projects and their associated metadata  

E-Print Network (OSTI)

large-scale microbial genome sequencing initiatives, e.g. ,in the history of genome sequencing projects: the completedfor publication of genome sequencing projects require the

Liolios, Konstantinos

2010-01-01T23:59:59.000Z

352

Materials Genome: CALPHAD, ESPEI, and Beyond  

Science Conference Proceedings (OSTI)

Materials Genomics Past & Future: From CALPHAD to Flight Modelling the Properties of Multi-Component Commercial Alloys Molecular Dynamics...

353

Robust classifying of prokaryotic genomes  

Science Conference Proceedings (OSTI)

In this paper, we propose a method to classify prokaryotic genomes using the agglomerative information bottleneck method for unsupervised clustering. Although the method we present here is closely related to a group of methods based on detecting the ... Keywords: Agglomerative clustering, COGs, Gene length, IB, Information bottleneck method, Jackknifing, NJ, Phylogenomics, UPGMA

Katerina Korenblat; Zeev Volkovich; Alexander Bolshoy

2012-10-01T23:59:59.000Z

354

Nuclear Organization and Genome Function  

E-Print Network (OSTI)

Nuclear Organization and Genome Function Kevin Van Bortle and Victor G. Corces Department-range interactions and have proposed roles in nuclear organization. In this review, we explore recent findings for the roles of insulators in nuclear organization. 163 Annu.Rev.CellDev.Biol.2012.28:163-187.Downloadedfromwww

Corces, Victor G.

355

Genomes and evolution Editorial overview  

E-Print Network (OSTI)

. co/i is true for the elephant", asserted Jacques Monod [l] during the heroic age of molecular biology-effective strategy to develop genome sequencing infrastructure as well as to provide grist for biologists' mills and illustrates the utility of studying things in pairs. These two species are highly divergent evolutionarily

Boguski, Mark S.

356

Investigation of Microwave Instability on Electron Storage Ring TLS  

Science Conference Proceedings (OSTI)

With the planned installation of a superconducting rf system, the new operation mode of TLS, the electron storage ring at NSRRC, is expected to double the beam intensity. Several accelerator physics topics need to be examined. Beam instability of single-bunch longitudinal microwave instability is one of these topics. We consider two approaches to measure the effective broad band impedance. We compare these measurement results with each other and to old data [Ref.1]. We calculate the threshold current of microwave instability with a mode-mixing analysis code written by Dr. K. Oide of KEK [Ref.2]. We also develop a multi-particle tracking code to simulate the instability. The results of simulation and measurement are compared and discussed. We conclude that doubling of beam current from 200 mA (1.5 mA/bunch) to 400 mA (3 mA/bunch) will not trigger the microwave instability even without a Landau cavity to lengthen the bunch. The benefit of Landau cavity is mainly for beam life time.

Wang, M.-H.; /NSRRC, Taiwan; Chao, A.; /SLAC

2005-05-17T23:59:59.000Z

357

Superradiant instabilities of rotating black holes in the time domain  

E-Print Network (OSTI)

Bosonic fields on rotating black hole spacetimes are subject to amplification by superradiance, which induces exponentially-growing instabilities (the `black hole bomb') in two scenarios: if the black hole is enclosed by a mirror, or if the bosonic field has rest mass. Here we present a time-domain study of the scalar field on Kerr spacetime which probes ultra-long timescales up to $t \\lesssim 5 \\times 10^6 M$, to reveal the growth of the instability. We describe an highly-efficient method for evolving the field, based on a spectral decomposition into a coupled set of 1+1D equations, and an absorbing boundary condition inspired by the `perfectly-matched layers' paradigm. First, we examine the mirror case to study how the instability timescale and mode structure depend on mirror radius. Next, we examine the massive-field, whose rich spectrum (revealed through Fourier analysis) generates `beating' effects which disguise the instability. We show that the instability is clearly revealed by tracking the stress-energy of the field in the exterior spacetime. We calculate the growth rate for a range of mass couplings, by applying a frequency-filer to isolate individual modal contributions to the time-domain signal. Our results are in accord with previous frequency-domain studies which put the maximum growth rate at $\\tau^{-1} \\approx 1.72 \\times 10^{-7} (GM/c^3)^{-1}$ for the massive scalar field on Kerr spacetime.

Sam R. Dolan

2012-12-06T23:59:59.000Z

358

April 20, 2012 NIST Genomes in a Bottle Workshop ...  

Science Conference Proceedings (OSTI)

... discussed the Archon Genomics XPrize work characterizing genomes and validating pipelines, Ryan Poplin discussed Broad's pipeline to analyze ...

2012-10-04T23:59:59.000Z

359

'Catch and Suppress' Control of Instabilities in High Performance  

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

'Catch and Suppress' Control of Instabilities in High Performance 'Catch and Suppress' Control of Instabilities in High Performance Fusion Plasmas Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) News & Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301) 903-8584 E: sc.fes@science.doe.gov More Information » October 2012 'Catch and Suppress' Control of Instabilities in High Performance Fusion Plasmas Real time steering of microwave beams is used to suppress deleterious modes on DIII-D. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Image courtesy of General Atomics

360

Neutrino signature of supernova hydrodynamical instabilities in three dimensions  

E-Print Network (OSTI)

The first full-scale three-dimensional (3D) core-collapse supernova (SN) simulations with sophisticated neutrino transport show pronounced effects of the standing accretion shock instability (SASI) for two high-mass progenitors (20 and 27 M_sun). In a low-mass progenitor (11.2 M_sun), large-scale convection is the dominant nonradial hydrodynamic instability in the postshock accretion layer. The SASI-associated modulation of the neutrino signal (80 Hz in our two examples) will be clearly detectable in IceCube or the future Hyper-Kamiokande detector, depending on progenitor properties, distance, and observer location relative to the main SASI sloshing direction. The neutrino signal from the next galactic SN can therefore diagnose the nature of the hydrodynamic instability.

Irene Tamborra; Florian Hanke; Bernhard Mueller; Hans-Thomas Janka; Georg Raffelt

2013-07-30T23:59:59.000Z

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


361

Non-axisymmetric instability of axisymmetric magnetic fields  

E-Print Network (OSTI)

The MHD instabilities can generate complex field topologies even if the initial field configuration is a very simple one. We consider the stability properties of magnetic configurations containing a toroidal and an axial field. In this paper, we concentrate mainly on the behavior of non-axisymmetric perturbations in axisymmetric magnetic configurations. The stability is treated by a linear analysis of ideal MHD equations.In the presence of an axial field, it is shown that the instability can occur for a wide range of the azimuthal wavenumber $m$, and its growth rate increases with increasing $m$. At given $m$, the growth rate is at its maximum for perturbations with the axial wave-vector that makes the Alfv\\'en frequency approximately vanishing. We argue that the instability of magnetic configurations in the ideal MHD can typically be dominated by perturbations with very short azimuthal and axial wavelengths.

Bonanno, Alfio

2008-01-01T23:59:59.000Z

362

Magnetic instabilities in collisionless astrophysical rotating plasma with anisotropic pressure  

Science Conference Proceedings (OSTI)

A technique is developed for analytical study of instabilities in collisionless astrophysical rotating plasma with anisotropic pressure that may lead to magnetic turbulence. Description is based on a pair of equations for perturbations of the radial magnetic field and the sum of magnetic field and perpendicular plasma pressures. From these equations, a canonical second-order differential equation for the perturbed radial magnetic field is derived and, subsequently, the dispersion relation for local perturbations. The paper predicts two varieties of hybrid instabilities due to the effects of differential plasma rotation and pressure anisotropy: The rotational-firehose and rotational-mirror ones. When the gravitation force is weak compared with the perpendicular pressure gradient, a new family of instabilities (the pressure-gradient-driven) is revealed.

Mikhailovskii, A. B.; Pustovitov, V. D.; Erokhin, N. N. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); Lominadze, J. G. [Kharadze Abastumani National Astrophysical Observatory, 2a, Kazbegi Ave., Tbilisi 0160 (Georgia); Nodia Institute of Geophysics, 1, Aleksidze Str., Tbilisi 0193 (Georgia); Smolyakov, A. I. [Institute of Nuclear Fusion, Russian Research Centre Kurchatov Institute, 1, Kurchatov Sq., Moscow 123182 (Russian Federation); University of Saskatchewan, 116 Science Place, Saskatoon S7N 5E2 (Canada); Churikov, A. P. [Syzran Branch of Samara Technical University, 45, Sovetskaya Str., Syzran, Samara Region 446001 (Russian Federation)

2008-06-15T23:59:59.000Z

363

DOE Joint Genome Institute: Genome of Simplest Animal Reveals Ancient  

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

21, 2008 21, 2008 Genome of Simplest Animal Reveals Ancient Lineage, Confounding Array of Complex Capabilities WALNUT CREEK, CA-As Aesop said, appearances are deceiving-even in life's tiniest critters. From first detection in the 1880s, clinging to the sides of an aquarium, to its recent characterization by the U.S. Department of Energy Joint Genome Institute (DOE JGI), a simple and primitive animal, Trichoplax adhaerens, appears to harbor a far more complex suite of capabilities than meets the eye. The findings, reported in the August 21 online edition of the journal Nature, establish a group of organisms as a branching point of animal evolution and identify sets of genes, or a "parts list," employed by organisms that have evolved along particular branches.

364

Status of Plasma Electron Hose Instability Studies in FACET  

SciTech Connect

In the FACET plasma-wakefield acceleration experiment a dense 23 GeV electron beam will interact with lithium and cesium plasmas, leading to plasma ion-channel formation. The interaction between the electron beam and the plasma sheath-electrons may lead to a fast growing electron hose instability. By using optics dispersion knobs to induce a controlled z-x tilt along the beam entering the plasma, we investigate the transverse behavior of the beam in the plasma as function of the tilt. We seek to quantify limits on the instability in order to further explore potential limitations on future plasma wakefield accelerators due to the electron hose instability. The FACET plasma-wakefield experiment at SLAC will study beam driven plasma wakefield acceleration. A dense 23 GeV electron beam will interact with lithium or cesium plasma, leading to plasma ion-channel formation. The interaction between the electron beam and the plasma sheath-electrons drives the electron hose instability, as first studied by Whittum. While Ref. [2] indicates the possibility of a large instability growth rate for typical beam and plasma parameters, other studies including have shown that several physical effects may mitigate the hosing growth rate substantially. So far there has been no quantitative benchmarking of experimentally observed hosing in previous experiments. At FACET we aim to perform such benchmarking by for example inducing a controlled z-x tilt along the beamentering the plasma, and observing the transverse behavior of the beam in the plasma as function. The long-term objective of these studies is to quantify potential limitations on future plasma wakefield accelerators due to the electron hose instability.

Adli, Erik; /U. Oslo; England, Robert Joel; Frederico, Joel; Hogan, Mark; Li, Selina Zhao; Litos, Michael Dennis; Nosochkov, Yuri; /SLAC; An, Weiming; Mori, Warren; /UCLA

2011-12-13T23:59:59.000Z

365

Whole genome sequencing and comparative genomic analyses of two Vibrio cholerae O139 Bengal-specific Podoviruses to other N4-like phages reveal extensive genetic diversity  

E-Print Network (OSTI)

Chen YJ, Chen Z, et al: Genome sequencing in microfabricatedas: Fouts et al. : Whole genome sequencing and comparativeOpen Access Whole genome sequencing and comparative genomic

2013-01-01T23:59:59.000Z

366

The ecoresponsive genome of Daphnia pulex  

Science Conference Proceedings (OSTI)

This document provides supporting material related to the sequencing of the ecoresponsive genome of Daphnia pulex. This material includes information on materials and methods and supporting text, as well as supplemental figures, tables, and references. The coverage of materials and methods addresses genome sequence, assembly, and mapping to chromosomes, gene inventory, attributes of a compact genome, the origin and preservation of Daphnia pulex genes, implications of Daphnia's genome structure, evolutionary diversification of duplicated genes, functional significance of expanded gene families, and ecoresponsive genes. Supporting text covers chromosome studies, gene homology among Daphnia genomes, micro-RNA and transposable elements and the 46 Daphnia pulex opsins. 36 figures, 50 tables, 183 references.

Colbourne, John K.; Pfrender, Michael E.; Gilbert, Donald; Thomas, W. Kelley; Tucker, Abraham; Oakley, Todd H.; Tokishita, Shinichi; Aerts, Andrea; Arnold, Georg J.; Basu, Malay Kumar; Bauer, Darren J.; Caceres, Carla E.; Carmel, Liran; Casola, Claudio; Choi, Jeong-Hyeon; Detter, John C.; Dong, Qunfeng; Dusheyko, Serge; Eads, Brian D.; Frohlich, Thomas; Geiler-Samerotte, Kerry A.; Gerlach, Daniel; Hatcher, Phil; Jogdeo, Sanjuro; Krijgsveld, Jeroen; Kriventseva, Evgenia V; Kltz, Dietmar; Laforsch, Christian; Lindquist, Erika; Lopez, Jacqueline; Manak, Robert; Muller, Jean; Pangilinan, Jasmyn; Patwardhan, Rupali P.; Pitluck, Samuel; Pritham, Ellen J.; Rechtsteiner, Andreas; Rho, Mina; Rogozin, Igor B.; Sakarya, Onur; Salamov, Asaf; Schaack, Sarah; Shapiro, Harris; Shiga, Yasuhiro; Skalitzky, Courtney; Smith, Zachary; Souvorov, Alexander; Sung, Way; Tang, Zuojian; Tsuchiya, Dai; Tu, Hank; Vos, Harmjan; Wang, Mei; Wolf, Yuri I.; Yamagata, Hideo; Yamada, Takuji; Ye, Yuzhen; Shaw, Joseph R.; Andrews, Justen; Crease, Teresa J.; Tang, Haixu; Lucas, Susan M.; Robertson, Hugh M.; Bork, Peer; Koonin, Eugene V.; Zdobnov, Evgeny M.; Grigoriev, Igor V.; Lynch, Michael; Boore, Jeffrey L.

2011-02-04T23:59:59.000Z

367

Gauge theories on hyperbolic spaces and dual wormhole instabilities  

Science Conference Proceedings (OSTI)

We study supergravity duals of strongly coupled four-dimensional gauge theories formulated on compact quotients of hyperbolic spaces. The resulting background geometries are represented by Euclidean wormholes, which complicate establishing the precise gauge theory/string theory correspondence dictionary. These backgrounds suffer from the nonperturbative instabilities arising from the D3D3-bar pair-production in the background four-form potential. We discuss conditions for suppressing this Schwingerlike instability. We find that Euclidean wormholes arising in this construction develop a naked singularity before they can be stabilized.

Buchel, Alex [Department of Applied Mathematics, University of Western Ontario, London, Ontario N6A 5B7 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9 (Canada)

2004-09-15T23:59:59.000Z

368

Production and identification of the ion-temperature-gradient instability  

SciTech Connect

In order to produce and study the ion-temperature-gradient instability, the Columbia Linear Machine has been modified to yield a peaked ion temperature and flattish density profiles. Under these conditions the parameter {eta}{sub {ital i}} (={ital d} ln{ital T}{sub {ital i}}/{ital d} ln{ital N}) exceeded the critical value and a strong instability has been observed. Further identification has been based on observation of the azimuthal and axial wavelengths, and the real frequency, appropriate for the mode.

Sen, A.K.; Chen, J.; Mauel, M. (Plasma Research Laboratory, Columbia University, New York, New York 10027 (US))

1991-01-28T23:59:59.000Z

369

Nuclear-Coupled Flow Instabilities and Their Effects on Dryout  

SciTech Connect

Nuclear-coupled flow/power oscillations in boiling water reactors (BWRs) are investigated experimentally and analytically. A detailed literature survey is performed to identify and classify instabilities in two-phase flow systems. The classification and the identification of the leading physical mechanisms of the two-phase flow instabilities are important to propose appropriate analytical models and scaling criteria for simulation. For the purpose of scaling and the analysis of the nonlinear aspects of the coupled flow/power oscillations, an extensive analytical modeling strategy is developed and used to derive both frequency and time domain analysis tools.

M. Ishii; X. Sunn; S. Kuran

2004-09-27T23:59:59.000Z

370

Sequencing Intractable DNA to Close Microbial Genomes  

Science Conference Proceedings (OSTI)

Advancement in high throughput DNA sequencing technologies has supported a rapid proliferation of microbial genome sequencing projects, providing the genetic blueprint for for in-depth studies. Oftentimes, difficult to sequence regions in microbial genomes are ruled intractable resulting in a growing number of genomes with sequence gaps deposited in databases. A procedure was developed to sequence such difficult regions in the non-contiguous finished Desulfovibrio desulfuricans ND132 genome (6 intractable gaps) and the Desulfovibrio africanus genome (1 intractable gap). The polynucleotides surrounding each gap formed GC rich secondary structures making the regions refractory to amplification and sequencing. Strand-displacing DNA polymerases used in concert with a novel ramped PCR extension cycle supported amplification and closure of all gap regions in both genomes. These developed procedures support accurate gene annotation, and provide a step-wise method that reduces the effort required for genome finishing.

Hurt, Jr., Richard Ashley [ORNL; Brown, Steven D [ORNL; Podar, Mircea [ORNL; Palumbo, Anthony Vito [ORNL; Elias, Dwayne A [ORNL

2012-01-01T23:59:59.000Z

371

Insights from Human/Mouse genome comparisons  

SciTech Connect

Large-scale public genomic sequencing efforts have provided a wealth of vertebrate sequence data poised to provide insights into mammalian biology. These include deep genomic sequence coverage of human, mouse, rat, zebrafish, and two pufferfish (Fugu rubripes and Tetraodon nigroviridis) (Aparicio et al. 2002; Lander et al. 2001; Venter et al. 2001; Waterston et al. 2002). In addition, a high-priority has been placed on determining the genomic sequence of chimpanzee, dog, cow, frog, and chicken (Boguski 2002). While only recently available, whole genome sequence data have provided the unique opportunity to globally compare complete genome contents. Furthermore, the shared evolutionary ancestry of vertebrate species has allowed the development of comparative genomic approaches to identify ancient conserved sequences with functionality. Accordingly, this review focuses on the initial comparison of available mammalian genomes and describes various insights derived from such analysis.

Pennacchio, Len A.

2003-03-30T23:59:59.000Z

372

Scales, Growth Rates, and Spectral Fluxes of Baroclinic Instability in the Ocean  

Science Conference Proceedings (OSTI)

An observational, modeling, and theoretical study of the scales, growth rates, and spectral fluxes of baroclinic instability in the ocean is presented, permitting a discussion of the relation between the local instability scale; the first ...

Ross Tulloch; John Marshall; Chris Hill; K. Shafer Smith

2011-06-01T23:59:59.000Z

373

A Simple Approximate Result for the Maximum Growth Rate of Baroclinic Instabilities  

Science Conference Proceedings (OSTI)

The Charney problem for baroclinic instability involves the quasi-geostrophic instability of a zonal flow on a ? plane where the zonal flow is characterized by a constant vertical shear. The atmosphere is non-Boussinesq and continuous. The ...

R. S. Lindzen; Brian Farrell

1980-07-01T23:59:59.000Z

374

Thermal Instability of Olivine-type LiMnPO4 Cathodes  

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

Thermal Instability of Olivine-type LiMnPO4 Cathodes Title Thermal Instability of Olivine-type LiMnPO4 Cathodes Publication Type Journal Article Year of Publication 2010 Authors...

375

Barotropic Rossby Waves Radiating from Tropical Instability Waves in the Pacific Ocean  

Science Conference Proceedings (OSTI)

Tropical instability waves are triggered by instabilities of the equatorial current systems, and their sea level signal, with peak amplitude near 5N, is one of the most prominent features of the dynamic topography of the tropics. Cross-spectral ...

J. Thomas Farrar

2011-06-01T23:59:59.000Z

376

Instabilities of bosonic spin currents in optical lattices  

SciTech Connect

We analyze the dynamical and energetic instabilities of spin currents in a system of two-component bosons in an optical lattice, with a particular focus on the Neel state. We consider both the weakly interacting superfluid and the strongly interacting Mott insulating limits as well as the regime near the superfluid-insulator transition and establish the criteria for the onset of these instabilities. We use Bogoliubov theory to treat the weakly interacting superfluid regime. Near the Mott transition, we calculate the stability phase diagram within a variational Gutzwiller wave-function approach. In the deep Mott limit we discuss the emergence of the Heisenberg model and calculate the stability diagram within this model. Though the Bogoliubov theory and the Heisenberg model (appropriate for the deep superfluid and the deep Mott-insulating phase, respectively) predict no dynamical instabilities, we find, interestingly, that between these two limiting cases there is a regime of dynamical instability. This result is relevant for the ongoing experimental efforts to realize a stable Neel-ordered state in multicomponent ultracold bosons.

Hui, Hoi-Yin; Barnett, Ryan; Sensarma, Rajdeep; Das Sarma, S. [Condensed Matter Theory Center and Joint Quantum Institute, Department of Physics, University of Maryland, College Park, Maryland 20742 (United States)

2011-10-15T23:59:59.000Z

377

Capillary instability in models for three-phase flow  

Science Conference Proceedings (OSTI)

Standard models for immiscible three-phase flow in porous media exhibit unusual behavior associated with loss of strict hyperbolicity. Anomalies were at one time thought to be confined to the region of nonhyperbolicity, where the purely convective form ... Keywords: capillary pressure instability, flow in porous media, nonunique Riemann solution

A. V. Azevedo; D. Marchesin; B. Plohr; K. Zumbrun

2002-09-01T23:59:59.000Z

378

Formation of Jets by Baroclinic Instability on Gas Planet Atmospheres  

Science Conference Proceedings (OSTI)

In this paper it is proposed that baroclinic instability of even a weak shear may play an important role in the generation and stability of the strong zonal jets observed in the atmospheres of the giant planets. The atmosphere is modeled as a two-...

Yohai Kaspi; Glenn R. Flierl

2007-09-01T23:59:59.000Z

379

Electrical charging during the sharkskin instability of a metallocene melt  

E-Print Network (OSTI)

Flow instabilities are widely studied because of their economical and theoretical interest, however few results have been published about the polymer electrification during the extrusion. Nevertheless the generation of the electrical charges is characteristic of the interaction between the polymer melt and the die walls. In our study, the capillary extrusion of a metallocene polyethylene (mPE) through a tungsten carbide die is characterized through accurate electrical measurements thanks a Faraday pail. No significant charges are observed since the extrudate surface remains smooth. However, as soon as the sharkskin distortion appears, measurable charges are collected (around 5 10-8 C/m2). Higher level of charges are measured during the spurt or the gross-melt fracture (g.m.f) defects. This work is focused on the electrical charging during the sharkskin instability. The variation of the electrical charges versus the apparent wall shear stress is investigated for different die geometries. This curve exhibits a linear increase, followed by a sudden growth just before the onset of the spurt instability. This abrupt charging corresponds also to the end of the sharkskin instability. It is also well-known that wall slip appears just at the same time, with smaller velocity values than during spurt flow. Our results indicate that electrification could be a signature of the wall slip. We show also that the electrification curves can be shifted according to the time-temperature superposition principle, leading to the conclusion that molecular features of the polymer are also involved in this process.

S. Tonon; A. Lavernhe-Gerbier; F. Flores; A. Allal; C. Guerret-Picourt

2007-07-18T23:59:59.000Z

380

Phantom dark energy with tachyonic instability: metric perturbations  

E-Print Network (OSTI)

We study the behavior of metric perturbations in a recently proposed model of phantom dark energy with tachyonic instability at long wavelengths. We find that metric perturbations exponentially grow in time, starting from very small values determined by vacuum fluctuations, and may become sizeable at late times. This property may be of interest for phenomenology.

S. Sergienko; V. Rubakov

2008-03-21T23:59:59.000Z

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


381

Spatially resolved instability measurements with a heavy ion beam probe  

SciTech Connect

A heavy ion beam probe was used to make simultaneous measurements of the amplitude and phase of both density and space potential fluctuations in an energetic arc plasma. Detailed comparison with theoretical predictions identifies a 70 KHz coherent oscillation as a Kelvin-Helmholtz instability localized to a region of strong fluid shear. (auth)

Jennings, W. C.; Hickok, R. L.; Glowienka, J. C.

1975-01-01T23:59:59.000Z

382

Ion-beam-driven resonant ion cyclotron instability  

SciTech Connect

The resonant ion-beam-driven electrostatic ion cyclotron instability is identified. Measured dispersion relation and onset vs. beam energy and density agree with numerical calculations based on a theory which includes beam acoustic terms. After amplitude saturation, velocity space diffusion of the beam ions is observed. (auth)

Hendel, H.W.; Yamada, M.; Seiler, S.W.; Ikezi, H.

1975-11-01T23:59:59.000Z

383

Thermal instability of thermonuclear plasma in a mirror field  

SciTech Connect

In this paper, the thermal stability of a thermonuclear plasma in a mirror reactor is obtained by a simple model. The effect of the loss of thermonuclear alpha particles due to collisional pitch-angel scattering into loss cones is included in this analysis. The effect of the collisional loss is significant, and it has a stabilizing effect on the thermal instability.

Mizuno, N. (Nihon Univ., Tokyo (Japan). Coll. of Science and Engineering)

1990-11-01T23:59:59.000Z

384

Parabolic resonances and instabilities Vered Rom-Kedara)  

E-Print Network (OSTI)

Parabolic resonances and instabilities Vered Rom-Kedara) Department of Applied Mathematics 1996; accepted for publication 30 August 1996 A parabolic resonance is formed when an integrable two-degrees-of-freedom d.o.f. Hamiltonian system possessing a circle of parabolic fixed points is perturbed. It is proved

385

Instability and morphology of polymer solutions coating a fiber  

E-Print Network (OSTI)

We report an experimental study on the dynamics of a thin film of polymer solution coating a vertical fiber. The liquid film has first a constant thickness and then undergoes the Rayleigh-Plateau instability which leads to the formation of sequences of drops, separated by a thin film, moving down at a constant velocity. Different polymer solutions are used, i.e. xanthan solutions and polyacrylamide (PAAm) solutions. These solutions both exhibit shear-rate dependence of the viscosity, but for PAAm solutions, there are strong normal stresses in addition of the shear-thinning effect. We characterize experimentally and separately the effects of these two non-Newtonian properties on the flow on the fiber. Thus, in the flat film observed before the emergence of the drops, only shear-thinning effect plays a role and tends to thin the film compared to the Newtonian case. The effect of the non-Newtonian rheology on the Rayleigh-Plateau instability is then investigated through the measurements of the growth rate and the wavelength of the instability. Results are in good agreement with linear stability analysis for a shear-thinning fluid. The effect of normal stress can be taken into account by considering an effective surface tension which tends to decrease the growth rate of the instability. Finally, the dependence of the morphology of the drops with the normal stress is investigated and a simplified model including the normal stress within the lubrication approximation provides good quantitative results on the shape of the drops.

Franois Boulogne; Ludovic Pauchard; Frdrique Giorgiutti-Dauphin

2012-05-17T23:59:59.000Z

386

Comparing new models of transverse instability with simulations  

SciTech Connect

Recently, Balbekov and Burov have produced an ordinary integro-differential equation that approximates the Vlasov equation for beams with wakefields and large space charge tune shift. The present work compares this model with simulations. In particular, the claim that certain types of transverse wakes cannot lead to mode coupling instabilities is explored.

Blaskiewicz M.

2012-05-20T23:59:59.000Z

387

Dynamical instabilities in density-dependent hadronic relativistic models  

Science Conference Proceedings (OSTI)

Unstable modes in asymmetric nuclear matter (ANM) at subsaturation densities are studied in the framework of relativistic mean-field density-dependent hadron models. The size of the instabilities that drive the system are calculated and a comparison with results obtained within the nonlinear Walecka model is presented. The distillation and antidistillation effects are discussed.

Santos, A. M.; Brito, L.; Providencia, C. [Centro de Fisica Teorica, Department of Physics, University of Coimbra, P-3004-516 Coimbra (Portugal)

2008-04-15T23:59:59.000Z

388

Modulational instability and solitons in nonlocal media with competing nonlinearities  

Science Conference Proceedings (OSTI)

We investigate analytically and numerically propagation and spatial localization of light in nonlocal media with competing nonlinearities. In particular, we discuss conditions for the modulational instability of plane waves and formation of spatial solitons. We show that the competing focusing and defocusing nonlinearities enable coexistence of dark or bright spatial solitons in the same medium by varying the intensity of the beam.

Esbensen, B. K.; Bache, M.; Bang, O. [DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby (Denmark); Wlotzka, A. [Department of Physics, Institut fuer Theoretische Festkoerperphysik, University of Karlsruhe, D-76128 Karlsruhe (Germany); Krolikowski, W. [Laser Physics Centre, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

2011-11-15T23:59:59.000Z

389

Laser-seeded modulation instability within LHC proton beams  

SciTech Connect

A new method for seeding the modulation instability (MI) within an SPS-LHC proton beam using a laser pulse is presented. Using simulations, we show that a laser pulse placed ahead of a proton beam excites axially symmetric selfmodulation modes within the proton beam and leads to peak accelerating fields that are comparable to previously proposed seeding methods.

Siemon, Carl; Khudik, Vladimir; Yi, S. Austin; Pukhov, Alexander; Shvets, Gennady [University of Texas at Austin, Austin, Texas 78712 (United States); Max-Planck-Institut fuer Physik, 80805 Muenchen (Germany); University of Texas at Austin, Austin, Texas 78712 (United States)

2012-12-21T23:59:59.000Z

390

Filamentation instability of current-driven dust ion-acoustic waves in a collisional dusty plasma  

Science Conference Proceedings (OSTI)

A theoretical investigation has been made of the dust ion-acoustic filamentation instability in an unmagnetized current-driven dusty plasma by using the Lorentz transformation formulas. The effect of collision between the charged particles with neutrals and their thermal motion on this instability is considered. Developing the filamentation instability of the current-driven dust ion-acoustic wave allows us to determine the period and the establishment time of the filamentation structure and threshold for instability development.

Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran 19839-63113 (Iran, Islamic Republic of); Haghtalab, T.; Khorashadizadeh, S. M. [Physics Department, Birjand University, Birjand 97179-63384 (Iran, Islamic Republic of)

2011-11-15T23:59:59.000Z

391

Genome Improvement at JGI-HAGSC  

Science Conference Proceedings (OSTI)

Since the completion of the sequencing of the human genome, the JGI has rapidly expanded its scientific goals in several DOE mission-relevant areas. At the JGI-HAGSC, we have kept pace with this rapid expansion of projects with our focus on assessing, assembling, improving and finishing eukaryotic whole genome shotgun (WGS) projects for which the shotgun sequence is generated at the Production Genomic Facility (JGI-PGF). We follow this by combining the draft WGS with genomic resources generated at JGI-HAGSC or in collaborator laboratories (including BAC end sequences, genetic maps and FLcDNA sequences) to produce an improved draft sequence. For eukaryotic genomes important to the DOE mission, we then add further information from directed experiments to produce reference genomic sequences that are publicly available for any scientific researcher. Also, we have continued our program for producing BAC-based finished sequence, both for adding information to JGI genome projects and for small BAC-based sequencing projects proposed through any of the JGI sequencing programs. We have now built our computational expertise in WGS assembly and analysis and have moved eukaryotic genome assembly from the JGI-PGF to JGI-HAGSC. We have concentrated our assembly development work on large plant genomes and complex fungal and algal genomes.

Grimwood, Jane: Schmutz, Jeremy, J.: Myers, Richard, M.

2012-03-03T23:59:59.000Z

392

Causes of Combustion Instabilities with Passive and Active Methods of Control for practical application to Gas Turbine Engines.  

E-Print Network (OSTI)

??Combustion at high pressure in applications such as rocket engines and gas turbine engines commonly experience destructive combustion instabilities. These instabilities results from interactions between (more)

Cornwell, Michael

2011-01-01T23:59:59.000Z

393

BUOYANCY INSTABILITIES IN A WEAKLY COLLISIONAL INTRACLUSTER MEDIUM  

SciTech Connect

The intracluster medium (ICM) of galaxy clusters is a weakly collisional plasma in which the transport of heat and momentum occurs primarily along magnetic-field lines. Anisotropic heat conduction allows convective instabilities to be driven by temperature gradients of either sign: the magnetothermal instability (MTI) in the outskirts of clusters and the heat-flux buoyancy-driven instability (HBI) in their cooling cores. We employ the Athena magnetohydrodynamic code to investigate the nonlinear evolution of these instabilities, self-consistently including the effects of anisotropic viscosity (i.e., Braginskii pressure anisotropy), anisotropic conduction, and radiative cooling. We find that, in all but the innermost regions of cool-core clusters, anisotropic viscosity significantly impairs the ability of the HBI to reorient magnetic-field lines orthogonal to the temperature gradient. Thus, while radio-mode feedback appears necessary in the central few Multiplication-Sign 10 kpc, heat conduction may be capable of offsetting radiative losses throughout most of a cool core over a significant fraction of the Hubble time. Magnetically aligned cold filaments are then able to form by local thermal instability. Viscous dissipation during cold filament formation produces accompanying hot filaments, which can be searched for in deep Chandra observations of cool-core clusters. In the case of MTI, anisotropic viscosity leads to a nonlinear state with a folded magnetic field structure in which field-line curvature and field strength are anti-correlated. These results demonstrate that, if the HBI and MTI are relevant for shaping the properties of the ICM, one must self-consistently include anisotropic viscosity in order to obtain even qualitatively correct results.

Kunz, Matthew W.; Stone, James M. [Department of Astrophysical Sciences, Princeton University, Peyton Hall, 4 Ivy Lane, Princeton, NJ 08544 (United States); Bogdanovic, Tamara; Reynolds, Christopher S., E-mail: kunz@astro.princeton.edu, E-mail: jstone@astro.princeton.edu, E-mail: tamarab@astro.umd.edu, E-mail: chris@astro.umd.edu [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States)

2012-08-01T23:59:59.000Z

394

Anomalous diffusion and ion heating in the presence of electrostatic hydrogen cyclotron instabilities  

DOE Green Energy (OSTI)

One- and two-dimensional simulations have been carried out to study electrostatic ion cyclotron instabilities for a hydrogen plasma in a strong magnetic field. It is found that strong ion heating and anomalous cross-field diffusion comparable to Bohm diffusion take place associated with the instability. Implications of the instability to the recent observations in fusion devices and space plasmas are discussed.

Okuda, H.; Cheng, C.Z.; Lee, W.W.

1980-11-01T23:59:59.000Z

395

Radio-frequency emission from an explosive instability in an electron beam  

SciTech Connect

The explosive instability which occurs when an electron beam moves through a helical resonator is studied. This instability can be exploited to generate rf oscillations at high efficiency (20% in these experiments). The spectral width is narrower than the characteristic width for linear instabilities.

Buts, V.A.; Izmailov, A.N.

1978-07-01T23:59:59.000Z

396

COMPARATIVE ASSESSMENT OF RADIATION-INDUCED GENE  

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

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

397

Radiation Induced Redox Reactions 1. Anions  

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

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

398

Radiation Induced Fragmentation of Diamide Extraction Agents...  

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

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

399

Mechanisms of radiation-induced gene responses  

Science Conference Proceedings (OSTI)

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

Woloschak, G.E.; Paunesku, T.

1996-10-01T23:59:59.000Z

400

Radiation-induced leiomyosarcoma of the oropharynx  

E-Print Network (OSTI)

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

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

2006-01-01T23:59:59.000Z

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


401

Radiation Induced Redox Reactions 2. Imidazolium Cations  

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

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

402

Radiation-induced disruption of skeletal remodeling  

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

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

403

History of the DOE Human Genome Program  

Office of Scientific and Technical Information (OSTI)

History of the DOE Human Genome Program History of the DOE Human Genome Program The following history is taken from the U.S. Department of Energy 1991-91 Human Genome Program Report (June 1992). This is an archived item. A brief history of the U.S. Department of Energy (DOE) Human Genome Program will be useful in a discussion of the objectives of the DOE program as well as those of the collaborative U.S. Human Genome Project. The Office of Health and Environmental Research (OHER) of DOE and its predecessor agencies--the Atomic Energy Commission and the Energy Research and Development Administration--have long sponsored research into genetics, both in microbial systems and in mammals, including basic studies on genome structure, replication, damage, and repair and the consequences of genetic

404

Keynote Presentation: Genome Beat (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)  

Science Conference Proceedings (OSTI)

Carl Zimmer, a reporter for the New York Times, speaks on "The Genome Beat," the opening keynote presentation at the JGI User 7th Annual Genomics of Energy & Environment Meeting on March 22, 2012 in Walnut Creek, Calif

Zimmer, Carl [New York Times

2012-03-20T23:59:59.000Z

405

DOE Joint Genome Institute: JGI & NERSC Partner for GenomicHigh...  

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

April 12, 2010 JGI & NERSC Partner for Genomic High-performance Computing WALNUT CREEK, CA-The Department of Energy Joint Genome Institute (JGI) and the National Energy Research...

406

In depth comparison of an individual's DNA and its lymphoblastoid cell line using whole genome sequencing  

E-Print Network (OSTI)

Yeung G, et al: Human genome sequencing using unchained basecell line using whole genome sequencing. BMC Genomics 2012cell line using whole genome sequencing Dorothee Nickles 1 ,

2012-01-01T23:59:59.000Z

407

Complete genome sequence of Sanguibacter keddieii type strain (ST-74T)  

E-Print Network (OSTI)

60%. Strains with a genome sequencing project registered inacknowledgements. Genome sequencing Genome project historyin Table 2. Table 2. Genome sequencing project information

Ivanova, Natalia

2010-01-01T23:59:59.000Z

408

The Pinus taeda genome is characterized by diverse and highly diverged repetitive sequences  

E-Print Network (OSTI)

deep transcriptome or genome sequencing, as well as experi-Three sets of whole genome shotgun sequencing were performedthroughput Whole Genome Shotgun Sequencing genomic DNA at a

2010-01-01T23:59:59.000Z

409

Complete genome sequence of Denitrovibrio acetiphilus type strain (N2460T)  

E-Print Network (OSTI)

of the complete genome sequencing and annotation. Figure 160%. Strains with a genome sequencing project registered inexamined to date. Genome sequencing and annotation Genome

Kiss, Hajnalka

2010-01-01T23:59:59.000Z

410

Complete genome sequence of Beutenbergia cavernae type strain (HKI 0122T)  

E-Print Network (OSTI)

of the complete genome sequencing and annotation. In60%. Strains with a genome-sequencing project regis- tered8] and the complete Genome sequencing and annotation Genome

Land, Miriam

2010-01-01T23:59:59.000Z

411

Plethodontid salamander mitochondrial genomics: A parsimony evaluation of character conflict and implications for historical biogeography  

E-Print Network (OSTI)

Mitochondrial DNA; Genomics; Biogeography; Appalachia. 1.salamander mitochondrial genomics: A parsimony evaluation of1,2 Department of Evolutionary Genomics, DOE Joint Genome

Macey, J. Robert

2005-01-01T23:59:59.000Z

412

Fueling the Future with Fungal Genomics  

E-Print Network (OSTI)

genome sequencing and bioenergy. Fungal Biology Reviews. 22:of fungal pathogens of bioenergy crops with sequenced hostand improve them to make bioenergy production efficient on

Grigoriev, Igor V.

2011-01-01T23:59:59.000Z

413

Today, DOE's Joint Genome Institute (a  

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

characterizing the basic principles and relationships underlying living systems. Social Impact: Armed with the DNA sequence of the human genome, scientists will be able to...

414

ORNL Genome Analysis Pipeline - Yeast (Saccharomyces cerevisiae...  

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

Grail (Microbial Gene Prediction System Internet Link) GrailEXP Genome Analysis Pipeline DomainParser PROSPECT (PROtein Structure Prediction and Evaluation Computer Toolkit)...

415

NIST and The Materials Genome Initiative  

Science Conference Proceedings (OSTI)

... the Materials Genome Ini(a(ve formed (NIST, DOE, DOD, NSF, NASA, NIH, USGS, NNSA, DARPA, NSA, OMB) 6/12: MGI White House Kickoff Event ...

2013-07-02T23:59:59.000Z

416

When is Reproducibility an Ethical Issue? Genomics ...  

Science Conference Proceedings (OSTI)

... Genomics, personalized medicine, and human error. ... Dr. Baggerly will present several case studies where simple errors may have put patients at risk ...

2013-03-20T23:59:59.000Z

417

Synthetic Genomics Inc | Open Energy Information  

Open Energy Info (EERE)

search Name Synthetic Genomics Inc. Place La Jolla, California Sector Hydro, Hydrogen, Renewable Energy Product California-based company planning to create new types of...

418

DOE Joint Genome Institute 2008 Progress Report  

E-Print Network (OSTI)

proteins for biofuel production. Trends in Mi- crobiology,could help improve biofuel production. Diatom Genome Helpsa key target. Current biofuel production meth- ods, such as

Gilbert, David

2009-01-01T23:59:59.000Z

419

ICME Successes: From Genome to Flight  

Science Conference Proceedings (OSTI)

Past success defines a clear path forward for major enhancement of materials genomics technology. Proceedings Inclusion? Definite: A combination print-CD...

420

Genomics Division: How to Contact Us  

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

How to Contact Us Please contact: Mary Miller, Senior Administrator Genomics Division Lawrence Berkeley National Laboratory 1 Cyclotron Road, Mailstop 84-171 Berkeley, CA 94720...

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


421

CI Announces Globus Genomics | Argonne National Laboratory  

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

CI Announces Globus Genomics April 9, 2013 Tweet EmailPrint The ArgonneUniversity of Chicago Computation Institute has announced a new sequencing analysis service called Globus...

422

DOE Joint Genome Institute 2008 Progress Report  

E-Print Network (OSTI)

Paterson, A. , et al. The Sorghum bicolor genome and thethe 730-million nucleotide Sorghum bicolor sequence, and thesoybean, eucalyp- tus, sorghum, foxtail millet, cassava,

Gilbert, David

2009-01-01T23:59:59.000Z

423

DOE JGI Releases Soybean Genome Assembly  

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

SoyMap team, comprising principal investigator Scott Jackson, Gary Stacey and Henry Nguyen, Jeff Doyle of Cornell University, William Beavis of the National Center for Genome...

424

Living with genome instability: the adaptation of phytoplasmas to diverse environments of their insect and plant hosts  

E-Print Network (OSTI)

Protein Loads a Single DnaB Helicase at a DnaA Box Hairpin.1996. The Interaction between Helicase and Primase Sets theprimase (dnaG), DNA helicase (dnaB), thymidylate kinase (

2006-01-01T23:59:59.000Z

425

Tangential neutral-beam-driven instabilities in the Princeton beta experiment  

Science Conference Proceedings (OSTI)

During tangential neutral beam injection into the PBX tokamak, bursts of two types of instabilities are observed. One instability occurs in the frequency range 120-210 kHz and the other oscillates predominately near the frequency of bulk plasma rotation (20-30 kHz). Both instabilities correlate with drops in neutron emission and burst in charge-exchange neutral flux, indicating that beam ions are removed from the center of the plasma by the instabilities. The central losses are comparable to the losses induced by the fishbone instability during perpendicular injection.

Heidbrink, W.W.; Bol, K.; Buchenauer, D.; Fonck, R.; Gammel, G.; Ida, K.; Kaita, R.; Kaye, S.; Kugel, H.; LeBlanc, B.

1986-07-01T23:59:59.000Z

426

Visualizing Magneto-Rotational Instability and Turbulent Angular Momentum  

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

Turbulent Angular Momentum Transport Turbulent Angular Momentum Transport Magneto-Rotational Instability and Turbulent Angular Momentum Transport hydroentropyvisit0400.s.x2005.png In space, gases and other matter often form swirling disks around attracting central objects such as newly formed stars. The presence of magnetic fields can cause the disks to become unstable and develop turbulence, causing the disk material to fall onto the central object. This project will carry out large-scale simulations to test theories on how turbulence can develop in such a scenario. These simulations may provide insights into magnetically caused instabilities being studied on a smaller scale in laboratory experiments. In this image volume rendering has been used to visualize the time evolution of hydrodynamic entropy. The color

427

Teasing Out the Nature of Structural Instabilities in Ceramic Compounds |  

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

Doubling Estimates of Light Elements in the Earth's Core Doubling Estimates of Light Elements in the Earth's Core A New Material for Warm-White LEDs Probing Ultrafast Solvation Dynamics with High Repetition-Rate Laser/X-ray Methodologies Ultrafast X-Ray Spectroscopy as a Probe of Nonequilibrium Dynamics in Ruthenium Complexes The Electronic Origin of Photoinduced Strain Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Teasing Out the Nature of Structural Instabilities in Ceramic Compounds MARCH 12, 2013 Bookmark and Share The simple perovskite structure of EuTiO3 illustrated above shows the essential competing structural instabilities. At the center of the figure is the oxygen cage rotation, and to the right is the central titanium

428

Spatially Modulated Instabilities for Scaling Solutions at Finite Charge Density  

E-Print Network (OSTI)

We consider finite charge density geometries which interpolate between AdS2 x R2 in the infrared and AdS4 in the ultraviolet, while traversing an intermediate regime of anisotropic Lifshitz scaling and hyperscaling violation. We work with Einstein-Maxwell-dilaton models and only turn on a background electric field. The spatially modulated instabilities of the near-horizon AdS2 part of the geometry are used to argue that the scaling solutions themselves should be thought of as being unstable -- in the deep infrared -- to spatially modulated phases. We identify instability windows for the scaling exponents, which are refined further by requiring the solutions to satisfy the null energy condition. This analysis reinforces the idea that, for large classes of models, spatially modulated phases describe the ground state of hyperscaling violating scaling geometries.

Sera Cremonini

2013-10-11T23:59:59.000Z

429

Electron Beam Instability in Left-Handed Media  

E-Print Network (OSTI)

We predict that two electron beams can develop an instability when passing through a slab of left-handed media (LHM). This instability, which is inherent only for LHM, originates from the backward Cherenkov radiation and results in a self-modulation of the beams and radiation of electromagnetic waves. These waves leave the sample via the rear surface of the slab (the beam injection plane) and form two shifted bright circles centered at the beams. A simulated spectrum of radiation has well-separated lines on top of a broad continuous spectrum, which indicates dynamical chaos in the system. The radiation intensity and its spectrum can be controlled either by the beams' current or by the distance between the two beams.

Yury P. Bliokh; Sergey Savel'ev; Franco Nori

2008-04-08T23:59:59.000Z

430

STAR HOPPERS: PLANET INSTABILITY AND CAPTURE IN EVOLVING BINARY SYSTEMS  

SciTech Connect

Many planets are observed in stellar binary systems, and their frequency may be comparable to that of planetary systems around single stars. Binary stellar evolution in such systems influences the dynamical evolution of the resident planets. Here, we study the evolution of a single planet orbiting one star in an evolving binary system. We find that stellar evolution can trigger dynamical instabilities that drive planets into chaotic orbits. This instability leads to planet-star collisions, exchange of the planet between the binary stars ('star hoppers'), and ejection of the planet from the system. The means by which planets can be recaptured is similar to the pull-down capture mechanism for irregular solar system satellites. Because planets often suffer close encounters with the primary on the asymptotic giant branch, captures during a collision with the stellar envelope are also possible for more massive planets. Such capture could populate the habitable zone around white dwarfs.

Kratter, Kaitlin M.; Perets, Hagai B. [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

2012-07-01T23:59:59.000Z

431

Rayleigh-Taylor Instability at Ionization Fronts: Perturbation Analysis  

E-Print Network (OSTI)

The linear growth rate of the Rayleigh-Taylor instability (RTI) at ionization fronts is investigated via perturbation analysis in the limit of incompressible fluids. In agreement with previous numerical studies is found that absorption of ionizing radiation inside the HII region due to hydrogen recombinations suppresses the growth of instabilities. In the limit of a large density contrast at the ionization front the RTI growth rate has the simple analytical solution n=-nur+(nur^2+gk)^(1/2), where nur is the hydrogen recombination rate inside the HII region, k is the perturbation's wavenumber and g is the effective acceleration in the frame of reference of the front. Therefore, the growth of surface perturbations with wavelengths lambda >> lambda_{cr} = 2\\pi g/nur^2 is suppressed by a factor (lambda_{cr}/4lambda)^(1/2) with respect to the non-radiative incompressible RTI. Implications on stellar and black hole feedback are briefly discussed.

Ricotti, Massimo

2013-01-01T23:59:59.000Z

432

Transposable Elements and Genetic Instabilities in Crop Plants  

DOE R&D Accomplishments (OSTI)

Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.

Burr, B.; Burr, F.

1981-04-10T23:59:59.000Z

433

Dynamical instabilities of warm npe matter: {delta} meson effects  

Science Conference Proceedings (OSTI)

The effects of {delta} mesons on the dynamical instabilities of cold and warm nuclear and stellar matter at subsaturation densities are studied in the framework of relativistic mean-field hadron models (NL3, NL{rho}, and NL{rho}{delta}) with the inclusion of the electromagnetic field. The distillation effect and the spinodals for all the models considered are discussed. The crust-core transition density and pressure are obtained as a function of temperature for {beta}-equilibrium matter with and without neutrino trapping. An estimation of the size of the clusters formed in the nonhomogeneous phase and the corresponding growth rates are made. It is shown that cluster sizes increase with temperature. The effects of the {delta} meson on the instability region are larger for low temperatures, very asymmetric matter, and densities close to the spinodal surface. It increases the distillation effect above {approx}0.4{rho}{sub 0} and has the opposite effect below that density.

Pais, Helena; Santos, Alexandre; Providencia, Constanca [Centro de Fisica Computacional, Department of Physics, University of Coimbra, 3004-516 Coimbra (Portugal)

2009-10-15T23:59:59.000Z

434

Chapter 27 -- Breast Cancer Genomics, Section VI, Pathology and Biological Markers of Invasive Breast Cancer  

SciTech Connect

Breast cancer is predominantly a disease of the genome with cancers arising and progressing through accumulation of aberrations that alter the genome - by changing DNA sequence, copy number, and structure in ways that that contribute to diverse aspects of cancer pathophysiology. Classic examples of genomic events that contribute to breast cancer pathophysiology include inherited mutations in BRCA1, BRCA2, TP53, and CHK2 that contribute to the initiation of breast cancer, amplification of ERBB2 (formerly HER2) and mutations of elements of the PI3-kinase pathway that activate aspects of epidermal growth factor receptor (EGFR) signaling and deletion of CDKN2A/B that contributes to cell cycle deregulation and genome instability. It is now apparent that accumulation of these aberrations is a time-dependent process that accelerates with age. Although American women living to an age of 85 have a 1 in 8 chance of developing breast cancer, the incidence of cancer in women younger than 30 years is uncommon. This is consistent with a multistep cancer progression model whereby mutation and selection drive the tumor's development, analogous to traditional Darwinian evolution. In the case of cancer, the driving events are changes in sequence, copy number, and structure of DNA and alterations in chromatin structure or other epigenetic marks. Our understanding of the genetic, genomic, and epigenomic events that influence the development and progression of breast cancer is increasing at a remarkable rate through application of powerful analysis tools that enable genome-wide analysis of DNA sequence and structure, copy number, allelic loss, and epigenomic modification. Application of these techniques to elucidation of the nature and timing of these events is enriching our understanding of mechanisms that increase breast cancer susceptibility, enable tumor initiation and progression to metastatic disease, and determine therapeutic response or resistance. These studies also reveal the molecular differences between cancer and normal that may be exploited to therapeutic benefit or that provide targets for molecular assays that may enable early cancer detection, and predict individual disease progression or response to treatment. This chapter reviews current and future directions in genome analysis and summarizes studies that provide insights into breast cancer pathophysiology or that suggest strategies to improve breast cancer management.

Spellman, Paul T.; Heiser, Laura; Gray, Joe W.

2009-06-18T23:59:59.000Z

435

Gradient instabilities of electromagnetic waves in Hall thruster plasma  

SciTech Connect

This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.

Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

2013-04-15T23:59:59.000Z

436

Quantum Suppression of the Rayleigh Instability in Nanowires  

E-Print Network (OSTI)

A linear stability analysis of metallic nanowires is performed in the free-electron model using quantum chaos techniques. It is found that the classical instability of a long wire under surface tension can be completely suppressed by electronic shell effects, leading to stable cylindrical configurations whose electrical conductance is a magic number 1, 3, 5, 6,... times the quantum of conductance. Our results are quantitatively consistent with recent experiments with alkali metal nanowires.

F. Kassubek; C. A. Stafford; Hermann Grabert; Raymond E. Goldstein

2000-06-14T23:59:59.000Z

437

Surface instability of binary compounds caused by sputter yield amplification  

Science Conference Proceedings (OSTI)

It is demonstrated that the flat surface of a binary material that is subjected to normal-incidence ion bombardment can be unstable even if the curvature dependence of the sputter yields is negligibly small. This unforeseen instability is brought about by sputter yield amplification, and it results in the formation of a disordered array of nanodots with the lighter of the two atomic species concentrated at the peaks of the dots.

Mark Bradley, R. [Department of Physics, Colorado State University, Fort Collins, Colorado 80523 (United States)

2012-06-01T23:59:59.000Z

438

Anomalous transport and stabilization of collisionless drift-wave instabilities  

SciTech Connect

Extensive numerical simulations have been carried out to study the enhanced transport processes associated with the collisionless drift wave instabilities. The results indicate that the shear is effective in reducing the anomalous particle diffusion as predicted by theory; however, it is less so for the accompanied electron heat transfer. The quasilinear decay of the density profile is found to be the dominant mechanism for the nonlinear saturation. (auth)

Lee, W.W.; Okuda, H.

1975-12-01T23:59:59.000Z

439

Kink instabilities and the gas-embedded Z-pinch  

SciTech Connect

A comparison of a previous gas-embedded Z-pinch experiment (by E. Smars) is made using a nonlinear theory of kink instability (by W. Manheimer, et al.). Good agreement is found for some experimental cases while for others the theory predicts too fast a growth of the kink. To account for this discrepancy the evolution of topologically different secondary currents is postulated. (auth)

Hartman, C.W.

1975-04-30T23:59:59.000Z

440

DOE Joint Genome Institute: Peach Genome Offers Insights into Breeding  

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

March 24, 2013 March 24, 2013 Peach Genome Offers Insights into Breeding Strategies for Biofuels Crops Rapidly growing trees like poplars and willows are candidate "biofuel crops" from which it is expected that cellulosic ethanol and higher energy content fuels can be efficiently extracted. Domesticating these crops requires a deep understanding of the physiology and genetics of trees, and scientists are turning to long-domesticated fruit trees for hints. The relationship between a peach and a poplar may not be obvious at first glance, but to botanists both trees are part of the rosid superfamily, which includes not only fruit crops like apples, strawberries, cherries, and almonds, but many other plants as well, including rose that gives the superfamily its name.

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


441

Phase Structure and Instability Problem in Color Superconductivity  

E-Print Network (OSTI)

We address the phase structure of color superconducting quark matter at high quark density. Under the electric and color neutrality conditions there appear various phases as a result of the Fermi surface mismatch among different quark flavors induced by finite strange quark mass; the color-flavor locked (CFL) phase where quarks are all energy gapped, the u-quark superconducting (uSC) phase where u-quarks are paired with either d- or s-quarks, the d-quark superconducting (dSC) phase that is the d-quark analogue of the uSC phase, the two-flavor superconducting (2SC) phase where u- and d-quarks are paired, and the unpaired quark matter (UQM) that is normal quark matter without pairing. Besides these possibilities, when the Fermi surface mismatch is large enough to surpass the gap energy, the gapless superconducting phases are expected. We focus our discussion on the chromomagnetic instability problem related to the gapless CFL (gCFL) onset and explore the instability regions on the phase diagram as a function of the temperature and the quark chemical potential. We sketch how to reach stable physical states inside the instability regions.

Kenji Fukushima

2005-10-22T23:59:59.000Z

442

On the interface instability during rapid evaporation in microgravity  

Science Conference Proceedings (OSTI)

The rapid evaporation of a superheated liquid (vapor explosion) under microgravity conditions is studied by direct numerical simulation. The time-dependent Navier-Stokes and energy equations coupled to the interface dynamics are solved using a two-dimensional finite-difference/front-tracking method. Large interface deformations, topology change, latent heat, surface tension and unequal material properties between the liquid and vapor phases are included in the simulations. A comparison of numerical results to the exact solution of a one-dimensional test problem shows excellent agreement. For the two-dimensional rapid evaporation problem, the vapor volume growth rate and unstable interface dynamics are studied for increasing levels of initial liquid superheat. As the superheat is increased the liquid-vapor interface experiences increasingly unstable energetic growth. These results indicate that heat transfer plays a very important role in the instability mechanism leading to vapor explosions. It is suggested that the Mullins-Sekerka instability could play a role in the instability initiation mechanism.

Juric, D. [Los Alamos National Lab., NM (United States). Theoretical Div.

1997-05-01T23:59:59.000Z

443

Nonlinear Theory of the Ablative Rayleigh-Taylor Instability  

SciTech Connect

Here, a model for the nonlinear Rayleigh-Talyor instability (RTI) of a steady ablation front based on a sharp boundary approximation is presented. The model includes the effect of mass ablation and represents a basic tool for investigating many aspects of the nonlinear ablative RTI relevant to inertial confinement fusion. The single mode analysis shows the development of a nonlinear exponential instability for wave numbers close to the linear cutoff. Such a nonlinear instability grows at a rate faster than the linear growth rate and leads to saturation amplitudes significantly larger than the classical value 0.1 lambda. We also found that linearly stable perturbations with wave numbers larger than the linear cutoff become unstable when their initial amplitudes exceed a threshold vlaue. The shedding of long wavelength modes via mode coupling is much greater than predicted by the classical RTI theory. The effects of ablation on the evolution of a front of bubbles is also investigated and the front acceleration is computed.

Sanz, J.; Betti, R.; Ramis, R.; Ramirez, J.

2004-12-03T23:59:59.000Z

444

Secular Instability and Planetesimal Formation in the Dust Layer  

E-Print Network (OSTI)

Late in the gaseous phase of a protostellar disk, centimeter-sized bodies probably settle into a thin ``dust layer'' at the midplane. A velocity difference between the dust layer and the gas gives rise to turbulence, which prevents further settling and direct gravitational instability of the layer. The associated drag on the surface of the layer causes orbital decay in a few thousand years---as opposed to a few hundred years for an isolated meter-sized body. Within this widely-accepted theoretical framework, we show that the turbulent drag causes radial instabilities even if the selfgravity of the layer is negligible. We formulate axisymmetric, height-integrated dynamical equations for the layer that incorporate turbulent diffusion of mass and momentum in radius and height, vertical settling, selfgravity, and resistance to compression due to gas entrained within the dust layer. In steady-state, the equations describe the inward radial drift of a uniform dust layer. In perturbation, overdense rings form on an orbital timescale with widths comparable to the dust-layer thickness. Selfgravity is almost irrelevant to the linear growth rate but will eventually fragment and collapse the rings into planetesimals larger than a kilometer. We estimate that the drag instability is most efficient at 1 AU when most of the ``dust'' mass lies in the size range 0.1-10 meters.

J. Goodman; B. Pindor

1999-12-28T23:59:59.000Z

445

ComBo : a visualization tool for comparative genomic data  

E-Print Network (OSTI)

Propelled by advances in sequencing technology, the advent of the genomic era brings the challenge of managing and interpreting massive amount of genomic data. A number of single-genome browsers have been developed for ...

Yu, Tamara H. (Tamara Hui)

2004-01-01T23:59:59.000Z

446

Evolutionary Genomics of Life in (and from) the Sea  

E-Print Network (OSTI)

291: 1304-1351. Table 1. Genomics information on the webLBNL-59356 Evolutionary Genomics of Life in (and from) thean engine for comparative genomics. The six largest centers

Boore, Jeffrey L.

2009-01-01T23:59:59.000Z

447

Structural Genomics of Minimal Organisms: Pipeline and Results  

E-Print Network (OSTI)

of recombinant proteins. J. Struct. Funct. Genomics 5:69-74.proteins. J. Struct. Funct. Genomics 5:69-74. Oganesyan,Structural Genomics of Minimal Organisms: Pipeline and

Kim, Sung-Hou

2008-01-01T23:59:59.000Z

448

The Impact of Structural Genomics: Expectations and Outcomes  

E-Print Network (OSTI)

Choi et al. , J Struct Funct Genomics 4, 31-4 (2003). H. M.Center for Structural Genomics, sequence families of unknownMCSG) Northeast Structural Genomics Consortium, Novel folds

Chandonia, John-Marc; Brenner, Steven E.

2005-01-01T23:59:59.000Z

449

Comparative genomics reveals evidence of marine adaptation in Salinispora species.  

E-Print Network (OSTI)

Orcutt B, et al: Ecological genomics of marine roseobacters.1037-1042. Penn and Jensen BMC Genomics 2012, 13:86 http://and Jensen: Comparative genomics reveals evidence of marine

Penn, Kevin; Jensen, Paul R

2012-01-01T23:59:59.000Z

450

Target Selection and Deselection at the Berkeley Structural Genomics Center  

E-Print Network (OSTI)

gene-set concept. Annu Rev Genomics Hum Genet 2000;1:99-116.SE. A tour of structural genomics. Nat Rev Genet 2001;2(10):M, Wang LK. Structural genomics: a pipeline for providing

Chandonia, John-Marc; Kim, Sung-Hou; Brenner, Steven E.

2005-01-01T23:59:59.000Z

451

Phytozome: A Comparative Platform for Green Plant Genomics  

E-Print Network (OSTI)

a growing plant comparative genomics resource. Nucleic AcidsL.A. (2011) The Sol Genomics Network (solgenomics.net):for comparative plant genomics. Nucleic Acids Res, 36, D959-

Goodstein, David M.

2012-01-01T23:59:59.000Z

452

UV Decontamination of MDA Reagents for Single Cell Genomics  

E-Print Network (OSTI)

Reagents for Single Cell Genomics Janey Lee 1* , Damon TigheReagents for Single Cell Genomics Janey Lee 1 , Damon TigheAbstract Single cell genomics, the amplification and

Lee, Janey

2011-01-01T23:59:59.000Z

453

Uses of antimicrobial genes from microbial genome  

DOE Patents (OSTI)

We describe a method for mining microbial genomes to discover antimicrobial genes and proteins having broad spectrum of activity. Also described are antimicrobial genes and their expression products from various microbial genomes that were found using this method. The products of such genes can be used as antimicrobial agents or as tools for molecular biology.

Sorek, Rotem; Rubin, Edward M.

2013-08-20T23:59:59.000Z

454

Whole Genome Duplications, Multi-Break Rearrangements, and Genome Halving Theorem  

E-Print Network (OSTI)

The Genome Halving Problem, motivated by the whole genome duplication events in molecular evolution, was solved by El-Mabrouk and Sankoff. The El-Mabrouk Sankoff algorithm is rather complex inspiring a quest for a simpler solution. An alternative approach to Genome Halving Problem based on the notion of the contracted breakpoint graph was recently proposed in [2]. This new technique reveals that while the El-MabroukSankoff result is correct in most cases, it does not hold in the case of unichromosomal genomes. This raises a problem of correcting El-MabroukSankoff analysis and devising an algorithm that deals adequately with all genomes. In this paper we efficiently classify all genomes into two classes and show that while the El-MabroukSankoff theorem holds for the first class, it is incorrect for the second class. The crux of our analysis is a new combinatorial invariant defined on duplicated permutations. Using this invariant we were able to come up with a full proof of the Genome Halving theorem and a polynomial algorithm for Genome Halving Problem (for unichromosomal genomes). We also give the first short proof of the original El-MabroukSankoff result for multichromosomal genomes. Finally, we discuss a generalization of Genome Halving Problem for a more general set of rearrangement operations (including transpositions) and propose an efficient algorithm for solving this problem. 1

Max A. Alekseyev; Pavel A. Pevzner

2007-01-01T23:59:59.000Z

455

Data Management for High-Throughput Genomics  

E-Print Network (OSTI)

Today's sequencing technology allows sequencing an individual genome within a few weeks for a fraction of the costs of the original Human Genome project. Genomics labs are faced with dozens of TB of data per week that have to be automatically processed and made available to scientists for further analysis. This paper explores the potential and the limitations of using relational database systems as the data processing platform for high-throughput genomics. In particular, we are interested in the storage management for high-throughput sequence data and in leveraging SQL and user-defined functions for data analysis inside a database system. We give an overview of a database design for high-throughput genomics, how we used a SQL Server database in some unconventional ways to prototype this scenario, and we will discuss some initial findings about the scalability and performance of such a more database-centric approach.

Roehm, Uwe

2009-01-01T23:59:59.000Z

456

The Arabidopsis lyrata genome sequence and the basis of rapid genome size change  

Science Conference Proceedings (OSTI)

In our manuscript, we present a high-quality genome sequence of the Arabidopsis thaliana relative, Arabidopsis lyrata, produced by dideoxy sequencing. We have performed the usual types of genome analysis (gene annotation, dN/dS studies etc. etc.), but this is relegated to the Supporting Information. Instead, we focus on what was a major motivation for sequencing this genome, namely to understand how A. thaliana lost half its genome in a few million years and lived to tell the tale. The rather surprising conclusion is that there is not a single genomic feature that accounts for the reduced genome, but that every aspect centromeres, intergenic regions, transposable elements, gene family number is affected through hundreds of thousands of cuts. This strongly suggests that overall genome size in itself is what has been under selection, a suggestion that is strongly supported by our demonstration (using population genetics data from A. thaliana) that new deletions seem to be driven to fixation.

Hu, Tina T.; Pattyn, Pedro; Bakker, Erica G.; Cao, Jun; Cheng, Jan-Fang; Clark, Richard M.; Fahlgren, Noah; Fawcett, Jeffrey A.; Grimwood, Jane; Gundlach, Heidrun; Haberer, Georg; Hollister, Jesse D.; Ossowski, Stephan; Ottilar, Robert P.; Salamov, Asaf A.; Schneeberger, Korbinian; Spannagl, Manuel; Wang, Xi; Yang, Liang; Nasrallah, Mikhail E.; Bergelson, Joy; Carrington, James C.; Gaut, Brandon S.; Schmutz, Jeremy; Mayer, Klaus F. X.; Van de Peer, Yves; Grigoriev, Igor V.; Nordborg, Magnus; Weigel, Detlef; Guo, Ya-Long

2011-04-29T23:59:59.000Z

457

Plant Genomics Vol 3.pmd  

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

Populus Populus Genome Initiative Stephen DiFazio Department of Biology, West Virginia University, Morgantown, West Virginia 26508-6057 USA Email: spdifazio@mail.wvu.edu 8 1 INTRODUCTION 1.1 Background on Populus Biology The genus Populus consists of about 29 species organized into six major sections that occur primarily in the Northern Hemisphere (Eckenwalder 1996). Species from the different sections of the genus have diverse ecological characteristics. Two of the most economically important sections (Aigeiros and Tacamahaca) contain species collectively known as cottonwoods. These occur mostly in riparian zones and are characterized by primarily ruderal life history, dominating early successional stages and thriving on flood-mediated disturbance (Braatne et al. 1996; Karrenberg et al. 2002). The other major section of the genus (section Populus,

458

Application of High Performance Computing to the DOE Joint Genomic...  

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

Application of High Performance Computing to the DOE Joint Genomic Institute's Data Challenges January 25-26, 2010 DOE Joint Genome Institute, Walnut Creek, CA USA -by invitation...

459

DOE Joint Genome Institute: JGI's Susannah Tringe Receives Prestigious...  

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

Energy (DOE) Office of Science Early Career Research Program has awarded a grant to DOE Joint Genome Institute scientist Susannah Green Tringe to conduct genomic studies of...

460

Rooted in Wonder: Joint Genome Institute Study Reveals Amazing...  

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

Rooted in Wonder: Joint Genome Institute Study Reveals Amazing World Underfoot Rooted in Wonder: Joint Genome Institute Study Reveals Amazing World Underfoot August 13, 2012 -...

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


461

JGI - Sequencing for the DOE Genomics: GTL Program  

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

Educational Resources MyJGI: Information for Collaborators Sequencing for the DOE Genomics: GTL Program For status information, see the Genome Projects section. For more...

462

The Microbial Genomics and Metagenomics (MGM) five-day  

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

Microbial Genomics and Metagenomics (MGM) five-day workshop (www.jgi.doe.gov meetingsmgm) provides strong and solid training in microbial genomic and metagenomic analysis and...

463

Genome resequencing in Populus: Revealing large-scale genome variation and implications on specialized-trait genomics  

Science Conference Proceedings (OSTI)

To date, Populus ranks among a few plant species with a complete genome sequence and other highly developed genomic resources. With the first genome sequence among all tree species, Populus has been adopted as a suitable model organism for genomic studies in trees. However, far from being just a model species, Populus is a key renewable economic resource that plays a significant role in providing raw materials for the biofuel and pulp and paper industries. Therefore, aside from leading frontiers of basic tree molecular biology and ecological research, Populus leads frontiers in addressing global economic challenges related to fuel and fiber production. The latter fact suggests that research aimed at improving quality and quantity of Populus as a raw material will likely drive the pursuit of more targeted and deeper research in order to unlock the economic potential tied in molecular biology processes that drive this tree species. Advances in genome sequence-driven technologies, such as resequencing individual genotypes, which in turn facilitates large scale SNP discovery and identification of large scale polymorphisms are key determinants of future success in these initiatives. In this treatise we discuss implications of genome sequence-enable technologies on Populus genomic and genetic studies of complex and specialized-traits.

Muchero, Wellington [ORNL; Labbe, Jessy L [ORNL; Priya, Ranjan [University of Tennessee, Knoxville (UTK); DiFazio, Steven P [West Virginia University, Morgantown; Tuskan, Gerald A [ORNL

2013-01-01T23:59:59.000Z

464

FORMING PLANETESIMALS BY GRAVITATIONAL INSTABILITY. I. THE ROLE OF THE RICHARDSON NUMBER IN TRIGGERING THE KELVIN-HELMHOLTZ INSTABILITY  

SciTech Connect

Gravitational instability (GI) of a dust-rich layer at the midplane of a gaseous circumstellar disk is one proposed mechanism to form planetesimals, the building blocks of rocky planets and gas giant cores. Self-gravity competes against the Kelvin-Helmholtz instability (KHI): gradients in dust content drive a vertical shear which risks overturning the dusty subdisk and forestalling GI. To understand the conditions under which the disk can resist the KHI, we perform three-dimensional simulations of stratified subdisks in the limit that dust particles are small and aerodynamically well coupled to gas, thereby screening out the streaming instability and isolating the KHI. Each subdisk is assumed to have a vertical density profile given by a spatially constant Richardson number Ri. We vary Ri and the midplane dust-to-gas ratio {mu}{sub 0} and find that the critical Richardson number dividing KH-unstable from KH-stable flows is not unique; rather, Ri{sub crit} grows nearly linearly with {mu}{sub 0} for {mu}{sub 0} = 0.3-10. Plausibly, a linear dependence arises for {mu}{sub 0} << 1 because in this regime the radial Kepler shear replaces vertical buoyancy as the dominant stabilizing influence. Why this dependence should persist at {mu}{sub 0} > 1 is a new puzzle. The bulk (height-integrated) metallicity is uniquely determined by Ri and {mu}{sub 0}. Only for disks of bulk solar metallicity is Ri{sub crit} {approx} 0.2, which is close to the classical value. Our empirical stability boundary is such that a dusty sublayer can gravitationally fragment and presumably spawn planetesimals if embedded within a solar metallicity gas disk {approx}4x more massive than the minimum-mass solar nebula; or a minimum-mass disk having {approx}3x solar metallicity; or some intermediate combination of these two possibilities. Gravitational instability seems possible without resorting to the streaming instability or to turbulent concentration of particles.

Lee, Aaron T.; Chiang, Eugene [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Asay-Davis, Xylar [Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Barranco, Joseph, E-mail: a.t.lee@berkeley.ed [Department of Physics and Astronomy, San Francisco State University, San Francisco, CA 94132 (United States)

2010-08-01T23:59:59.000Z

465

Low Dose Radiation Research Program: Research Highlights - Collateral  

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

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

466

Kelvin-Helmholtz instability in a strongly coupled dusty plasma medium  

Science Conference Proceedings (OSTI)

The Kelvin-Helmholtz (KH) instability in the context of strongly coupled dusty plasma medium has been investigated. In particular, the role of transverse shear and the compressional acoustic modes in both the linear and nonlinear regimes of the KH instability has been studied. It is observed that in addition to the conventional nonlocal KH instability, there exists a local instability in the strong coupling case. The interplay of the KH mode with this local instability shows up in the simulations as an interesting phenomenon of recurrence in the nonlinear regime. Thus, a cyclic KH instability process is observed to occur. These cyclic events are associated with bursts of activity in terms of transverse and compressional wave generation in the medium.

Tiwari, Sanat Kumar; Das, Amita; Patel, Bhavesh G. [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Angom, Dilip [Physical Research Laboratory, Ahmedabad 380 009 (India); Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India); Physical Research Laboratory, Ahmedabad 380 009 (India)

2012-07-15T23:59:59.000Z

467

CEMM is studying a variety of instabilities in tokamaks  

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

Extended) MHD Case Study Extended) MHD Case Study Large Scale Computing and Storage Requirements for Fusion Energy Sciences FES/ASCR/NERSC Workshop August 3-4, 2010 Stephen C. Jardin Princeton Plasma Physics Laboratory In consultation with J. Breslau, J. Chen, N. Ferraro, G. Fu, S. Kruger, D. Schnack, C. Sovinec, H. Strauss, L. Sugiyama outline * Types of calculations performed * Equations solved * Which codes are used * General properties of Implicit MHD codes * Scaling studies * Kinetic closures * Future trends * Summary MHD codes are used for studying a variety of instabilities in tokamaks: Understanding these is very high priority for ITER "sawtooth oscillations" Disruptions caused by short wave-length modes interacting

468

Theoretical and Experimental Studies of Magneto-Rayleigh-Taylor Instabilities  

SciTech Connect

Magneto-Rayleigh-Taylor instability (MRT) is important to magnetized target fusion, wire-array z-pinches, and equation-of-state studies using flyer plates or isentropic compression. It is also important to the study of the crab nebula. The investigators performed MRT experiments on thin foils, driven by the mega-ampere linear transformer driver (LTD) facility completed in their laboratory. This is the first 1-MA LTD in the USA. Initial experiments on the seeding of MRT were performed. Also completed was an analytic study of MRT for a finite plasma slab with arbitrary magnetic fields tangential to the interfaces. The effects of magnetic shear and feedthrough were analyzed.

Lau, Yue Ying [University of Michigan] [University of Michigan; Gilgenbach, Ronald [University of Michigan] [University of Michigan

2013-07-07T23:59:59.000Z

469

Striped instability of a holographic Fermi-like liquid  

E-Print Network (OSTI)

We consider a holographic description of a system of strongly-coupled fermions in 2+1 dimensions based on a D7-brane probe in the background of D3-branes. The black hole embedding represents a Fermi-like liquid. We study the excitations of the Fermi liquid system. Above a critical density which depends on the temperature, the system becomes unstable towards an inhomogeneous modulated phase which is similar to a charge density and spin wave state. The essence of this instability can be effectively described by a Maxwell-axion theory with a background electric field. We also consider the fate of zero sound at non-zero temperature.

Oren Bergman; Niko Jokela; Gilad Lifschytz; Matthew Lippert

2011-06-20T23:59:59.000Z

470

NUMERICAL STUDY OF THE VISHNIAC INSTABILITY IN SUPERNOVA REMNANTS  

Science Conference Proceedings (OSTI)

The Vishniac instability is thought to explain the complex structure of radiative supernova remnants in their Pressure-Driven Thin Shell (PDTS) phase after a blast wave (BW) has propagated from a central explosion. In this paper, the propagation of the BW and the evolution of the PDTS stage are studied numerically with the two-dimensional (2D) code HYDRO-MUSCL for a finite-thickness shell expanding in the interstellar medium (ISM). Special attention is paid to the adiabatic index, {gamma}, and three distinct values are taken for the cavity ({gamma}{sub 1}), the shell ({gamma}{sub 2}), and the ISM ({gamma}{sub 3}) with the condition {gamma}{sub 2} < {gamma}{sub 1}, {gamma}{sub 3}. This low value of {gamma}{sub 2} accounts for the high density in the shell achieved by a strong radiative cooling. Once the spherical background flow is obtained, the evolution of a 2D-axisymmetric perturbation is computed from the linear to the nonlinear regime. The overstable mechanism, previously demonstrated theoretically by E. T. Vishniac in 1983, is recovered numerically in the linear stage and is expected to produce and enhance anisotropies and clumps on the shock front, leading to the disruption of the shell in the nonlinear phase. The period of the increasing oscillations and the growth rate of the instability are derived from several points of view (the position of the perturbed shock front, mass fluxes along the shell, and density maps), and the most unstable mode differing from the value given by Vishniac is computed. In addition, the influence of several parameters (the Mach number, amplitude and wavelength of the perturbation, and adiabatic index) is examined and for wavelengths that are large enough compared to the shell thickness, the same conclusion arises: in the late stage of the evolution of the radiative supernova remnant, the instability is dampened and the angular initial deformation of the shock front is smoothed while the mass density becomes uniform with the angle. As a result, our model shows that the supernova remnant returns to a stable evolution and the Vishniac instability does not lead to the fragmentation of the shock as predicted by the theory.

Michaut, C.; Cavet, C.; Bouquet, S. E.; Roy, F.; Nguyen, H. C., E-mail: claire.michaut@obspm.fr [LUTH, Observatoire de Paris, CNRS, Universite Paris-Diderot, F-92190 Meudon (France)

2012-11-10T23:59:59.000Z

471

Nonstationary Rayleigh-Taylor instability in supernova ejecta  

SciTech Connect

This paper studies the effect of a nonstationary shell acceleration on the development of the Rayleigh-Taylor instability (RTI) in supernovae remnants (SNRs). Two groups of solutions describing acceleration and deceleration phase of the SNR shell are obtained. Using a special transformation (co-moving coordinate frame), an exact dispersion relation for nonstationary RTI is derived. It is shown that compressible and incompressible branches are separated for the spherically symmetric flow and only the former is unstable. The exact analytic solution is compared to a simpler WKB-like analysis and a good agreement is shown, which proves that this analysis can be useful and easily extended to further applications.

Ribeyre, X.; Hallo, L.; Tikhonchuk, V. T.; Bouquet, S.; Sanz, J. [Centre Lasers Intenses et Applications, Universite Bordeaux 1-CNRS-CEA, 33405 Talence Cedex (France); Commissariat a l'Energie Atomique, DIF/Departement de Physique Theorique et Appliquee, 91680, Bruyeres le Chatel (France); E.T.S.I., Aeronauticos, Universidad Politecnica de Madrid, Madrid 28040 (Spain)

2007-11-15T23:59:59.000Z

472

Analysis of beam loss induced abort kicker instability  

SciTech Connect

Through more than a decade of operation, we have noticed the phenomena of beam loss induced kicker instability in the RHIC beam abort systems. In this study, we analyze the short term beam loss before abort kicker pre-fire events and operation conditions before capacitor failures. Beam loss has caused capacitor failures and elevated radiation level concentrated at failed end of capacitor has been observed. We are interested in beam loss induced radiation and heat dissipation in large oil filled capacitors and beam triggered thyratron conduction. We hope the analysis result would lead to better protection of the abort systems and improved stability of the RHIC operation.

Zhang W.; Sandberg, J.; Ahrens, L.; Fischer, W.; Hahn, H.; Mi, J.; Pai, C.; Tan, Y.

2012-05-20T23:59:59.000Z

473

Non-modal analysis of the diocotron instability: Plane geometry  

Science Conference Proceedings (OSTI)

The comprehensive investigation of the temporal evolution of the diocotron instability of the plane electron strip on the linear stage of its development is performed. By using the method of Kelvin of the shearing modes, the role of the initial perturbations of the electron density is elucidated, which is connected with the problem of the continuous spectrum. The linear non-modal evolution process detected by the solution of the initial value problem, leads toward convergence to the phase-locking configuration of the mutually growing normal modes.

Mikhailenko, V. V. [Research Institute of Computer, Information and Communication, Pusan National University, Busan 609735 (Korea, Republic of); June Lee, Hae [Department of Electrical Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Mikhailenko, V. S. [V.N. Karazin Kharkov National University, 61108 Kharkov (Ukraine)

2012-08-15T23:59:59.000Z

474

Viscoelastic Suppression of Gravity-Driven Counterflow Instability  

E-Print Network (OSTI)

Attempts to achieve ``top kill'' of actively flowing oil wells by insertion of dense drilling ``muds'', i.e., slurries of dense minerals, from above will fail if the Kelvin-Helmholtz instability in the gravity-driven counterflow produces turbulence that breaks up the denser fluid into small droplets. Here we estimate the droplet size to be sub-mm for fast flows and suggest the addition of a shear-thickening polymer to suppress turbulence. Laboratory experiments show a progression from droplet formation to complete turbulence suppression at the relevant high velocities, illustrating rich new physics accessible by using a shear-thickening liquid in gravity driven counter-streaming flows.

Beiersdorfer, P; Layne, D; Magee, E W

2010-01-01T23:59:59.000Z

475

Violent Crime, Residential Instability and Mobility: Does the Relationship Differ in Minority Neighborhoods?  

E-Print Network (OSTI)

PAPER Violent Crime, Residential Instability and Mobility:violent crime and residential stability in neighborhoods. Wea traditional index of residential stability and a novel

Boggess, Lyndsay N.; Hipp, John R.

2010-01-01T23:59:59.000Z

476

A small trip in the untranquil world of genomes  

Science Conference Proceedings (OSTI)

Genomes are dynamic molecules that are constantly undergoing mutations and rearrangements. The latter are large scale changes in a genome organisation that participate in the evolutionary and speciation process, but may also be involved in inherited ... Keywords: Breakpoint region, Conserved segment, Genome dynamics, Rearrangement, Synteny block, Whole genome alignment

Claire Lemaitre; Marie-France Sagot

2008-05-01T23:59:59.000Z

477

Genome Engineering with TAL Effector Nucleases  

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

Genome Engineering with TAL Effector Nucleases Print Genome Engineering with TAL Effector Nucleases Print Genome engineering (GE), an emerging discipline in which a DNA sequence is altered at a single position, has a wide variety of potential uses, such as the correction of gene sequences in patients suffering from genetic diseases, the modification or insertion of genes in plants, and the generation of unique cell lines for treatment of diseases such as cancer. GE requires the development of molecular tools that can search out and bind to one unique site within a complex genome while avoiding 'off-target' interactions across the remaining billions of DNA bases present in a cell's nucleus. Using ALS Beamline 5.0.2, researchers have solved the structure of one such tool called a TAL protein, learning its mechanism of action for DNA recognition and binding.

478

Genome Engineering with TAL Effector Nucleases  

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

Genome Engineering with TAL Effector Nucleases Print Genome Engineering with TAL Effector Nucleases Print Genome engineering (GE), an emerging discipline in which a DNA sequence is altered at a single position, has a wide variety of potential uses, such as the correction of gene sequences in patients suffering from genetic diseases, the modification or insertion of genes in plants, and the generation of unique cell lines for treatment of diseases such as cancer. GE requires the development of molecular tools that can search out and bind to one unique site within a complex genome while avoiding 'off-target' interactions across the remaining billions of DNA bases present in a cell's nucleus. Using ALS Beamline 5.0.2, researchers have solved the structure of one such tool called a TAL protein, learning its mechanism of action for DNA recognition and binding.

479

Joint Genome Institute (JGI) Projects at NERSC  

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

Joint Genome Institute Joint Genome Institute (JGI) Joint Genome Institute (JGI) nicole-illumina-flowcell.jpg Key Challenges: Ensuring that there is a robust computational infrastructure for managing, storing and gleaning scientific insights from the torrent of data that constantly flows from the advanced sequencing platforms at the Department of Energy Joint Genome Institute (JGI). JGI sequencing capacity exceeds 40 billion DNA base pairs per year and is growing at a rate that exceeds computer hardware improvements, with exponential increases in computation and storage needed. JGI will generate about 1 petabyte of data in their first year as a NERSC partner; this is expected to double each year. Why it Matters: JGI is the primary production sequencing facility for the DOE. By revealing the genetic blueprint and fundamental principles that

480

Genome Engineering with TAL Effector Nucleases  

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

Genome Engineering with TAL Effector Nucleases Print Genome Engineering with TAL Effector Nucleases Print Genome engineering (GE), an emerging discipline in which a DNA sequence is altered at a single position, has a wide variety of potential uses, such as the correction of gene sequences in patients suffering from genetic diseases, the modification or insertion of genes in plants, and the generation of unique cell lines for treatment of diseases such as cancer. GE requires the development of molecular tools that can search out and bind to one unique site within a complex genome while avoiding 'off-target' interactions across the remaining billions of DNA bases present in a cell's nucleus. Using ALS Beamline 5.0.2, researchers have solved the structure of one such tool called a TAL protein, learning its mechanism of action for DNA recognition and binding.

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