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1

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

2

ASSESSMENT OF INDIVIDUAL VARIATION IN DNA DOUBLE-STRAND BREAK REPAIR CAPACITY IN HUMAN DIPLOID FIBROBLASTS  

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

ASSESSMENT OF INDIVIDUAL VARIATION IN DNA DOUBLE-STRAND ASSESSMENT OF INDIVIDUAL VARIATION IN DNA DOUBLE-STRAND BREAK REPAIR CAPACITY IN HUMAN DIPLOID FIBROBLASTS Paul F. Wilson, John M. Hinz, Peter B. Nham, Salustra S. Urbin, Cynthia B. Thomas, Irene M. Jones, and Larry H. Thompson Biosciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA The induction of bi-stranded clustered DNA damage (BCD), which includes direct DNA double-strand breaks (DSBs), is a hallmark of ionizing radiation (IR) exposure. Incorrectly repaired DSBs can cause chromosomal rearrangements and an increased risk of genomic instability and cancer. Because there is polymorphic variation in DNA repair genes and much of this variation is predicted to have a functional impact, healthy people likely vary in their capacity to repair DSBs and other BCD. This project

3

The Role of DNA double-strand break repair in cellular response to low  

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

DNA double-strand break repair in cellular response to low DNA double-strand break repair in cellular response to low dose radiation exposure. David J. Chen Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas TX 75390 It has been assumed that molecular pathways that involved in the biological response for low dose of radiation should be similar to those for high dose radiation in general. The low dose-rate effect and DNA double-strand break repair are inextricably linked in mammalian cells. It has been reported that mammalian mutant cells deficient in nonhomologous end join (NHEJ) pathway have little or no cellular recovery when expose to low-dose-rate radiation. Recently, it has also been reported that cells deficient in

4

A Key Step in Repairing DNA Double-Strand Breaks | Advanced Photon Source  

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

X-ray Rainbow X-ray Rainbow An Insulating Breakthrough 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 A Key Step in Repairing DNA Double-Strand Breaks JANUARY 10, 2007 Bookmark and Share The atomic structure of the protein 53BP1 identified by Mayo researchers. (Courtesy: Mayo Clinic) A team of Mayo Clinic researchers has uncovered a key step in the molecular pathway of repairing DNA double-strand breaks. The studies were carried out using the 19-ID beamline (SBC-CAT) at the Advanced Photon Source (APS, Argonne) and the X12-C beamline at the National Synchrotron Light Source (NSLS, Brookhaven National Laboratory). Both the APS and the NSLS are funded by the U.S. Department of Energy's Office of Basic Energy

5

Sulforaphane induces DNA double strand breaks predominantly repaired by homologous recombination pathway in human cancer cells  

Science Conference Proceedings (OSTI)

Cytotoxicity and DNA double strand breaks (DSBs) were studied in HeLa cells treated with sulforaphane (SFN), a well-known chemo-preventive agent. Cell survival was impaired by SFN in a concentration and treatment time-dependent manner. Both constant field gel electrophoresis (CFGE) and {gamma}-H2AX assay unambiguously indicated formation of DSBs by SFN, reflecting the cell survival data. These DSBs were predominantly processed by homologous recombination repair (HRR), judging from the SFN concentration-dependent manner of Rad51 foci formation. On the other hand, the phosphorylation of DNA-PKcs, a key non-homologous end joining (NHEJ) protein, was not observed by SFN treatment, suggesting that NHEJ may not be involved in DSBs induced by this chemical. G2/M arrest by SFN, a typical response for cells exposed to ionizing radiation was also observed. Our new data indicate the clear induction of DSBs by SFN and a useful anti-tumor aspect of SFN through the induction of DNA DSBs.

Sekine-Suzuki, Emiko [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Yu, Dong [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kubota, Nobuo [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Okayasu, Ryuichi [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Anzai, Kazunori [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Graduate School of Advanced Integration Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan)], E-mail: anzai@nirs.go.jp

2008-12-12T23:59:59.000Z

6

Accumulation of DNA Double-Strand Breaks in Normal Tissues After Fractionated Irradiation  

SciTech Connect

Purpose: There is increasing evidence that genetic factors regulating the recognition and/or repair of DNA double-strand breaks (DSBs) are responsible for differences in radiosensitivity among patients. Genetically defined DSB repair capacities are supposed to determine patients' individual susceptibility to develop adverse normal tissue reactions after radiotherapy. In a preclinical murine model, we analyzed the impact of different DSB repair capacities on the cumulative DNA damage in normal tissues during the course of fractionated irradiation. Material and Methods: Different strains of mice with defined genetic backgrounds (SCID{sup -/-} homozygous, ATM{sup -/-} homozygous, ATM{sup +/-}heterozygous, and ATM{sup +/+}wild-type mice) were subjected to single (2 Gy) or fractionated irradiation (5 x 2 Gy). By enumerating gammaH2AX foci, the formation and rejoining of DSBs were analyzed in organs representative of both early-responding (small intestine) and late-responding tissues (lung, kidney, and heart). Results: In repair-deficient SCID{sup -/-} and ATM{sup -/-}homozygous mice, large proportions of radiation-induced DSBs remained unrepaired after each fraction, leading to the pronounced accumulation of residual DNA damage after fractionated irradiation, similarly visible in early- and late-responding tissues. The slight DSB repair impairment of ATM{sup +/-}heterozygous mice was not detectable after single-dose irradiation but resulted in a significant increase in unrepaired DSBs during the fractionated irradiation scheme. Conclusions: Radiation-induced DSBs accumulate similarly in acute- and late-responding tissues during fractionated irradiation, whereas the whole extent of residual DNA damage depends decisively on the underlying genetically defined DSB repair capacity. Moreover, our data indicate that even minor impairments in DSB repair lead to exceeding DNA damage accumulation during fractionated irradiation and thus may have a significant impact on normal tissue responses in clinical radiotherapy.

Ruebe, Claudia E., E-mail: claudia.ruebe@uks.e [Department of Radiation Oncology, Saarland University, Homburg/Saar (Germany); Fricke, Andreas; Wendorf, Juliane; Stuetzel, Annika; Kuehne, Martin [Department of Radiation Oncology, Saarland University, Homburg/Saar (Germany); Ong, Mei Fang [Institute of Medical Biometrics, Epidemiology and Medical Informatics, Saarland University, Homburg/Saar (Germany); Lipp, Peter [Institute for Molecular Cell Biology, Saarland University, Homburg/Saar (Germany); Ruebe, Christian [Department of Radiation Oncology, Saarland University, Homburg/Saar (Germany)

2010-03-15T23:59:59.000Z

7

Induction and Rejoining of DNA Double Strand Breaks Assessed by H2AX Phosphorylation in Melanoma Cells Irradiated with Proton and Lithium Beams  

SciTech Connect

Purpose: The aim of this study was to evaluate the induction and rejoining of DNA double strand breaks (DSBs) in melanoma cells exposed to low and high linear energy transfer (LET) radiation. Methods and Materials: DSBs and survival were determined as a function of dose in melanoma cells (B16-F0) irradiated with monoenergetic proton and lithium beams and with a gamma source. Survival curves were obtained by clonogenic assay and fitted to the linear-quadratic model. DSBs were evaluated by the detection of phosphorylated histone H2AX ({gamma}H2AX) foci at 30 min and 6 h post-irradiation. Results: Survival curves showed the increasing effectiveness of radiation as a function of LET. {gamma}H2AX labeling showed an increase in the number of foci vs. dose for all the radiations evaluated. A decrease in the number of foci was found at 6 h post-irradiation for low LET radiation, revealing the repair capacity of DSBs. An increase in the size of {gamma}H2AX foci in cells irradiated with lithium beams was found, as compared with gamma and proton irradiations, which could be attributed to the clusters of DSBs induced by high LET radiation. Foci size increased at 6 h post-irradiation for lithium and proton irradiations in relation with persistent DSBs, showing a correlation with surviving fraction. Conclusions: Our results showed the response of B16-F0 cells to charged particle beams evaluated by the detection of {gamma}H2AX foci. We conclude that {gamma}H2AX foci size is an accurate parameter to correlate the rejoining of DSBs induced by different LET radiations and radiosensitivity.

Ibanez, Irene L. [Comision Nacional de Energia Atomica, San Martin (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Bracalente, Candelaria [Comision Nacional de Energia Atomica, San Martin (Argentina); Molinari, Beatriz L. [Comision Nacional de Energia Atomica, San Martin (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Palmieri, Monica A. [Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina); Policastro, Lucia [Comision Nacional de Energia Atomica, San Martin (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Kreiner, Andres J. [Comision Nacional de Energia Atomica, San Martin (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina); Burlon, Alejandro A. [Comision Nacional de Energia Atomica, San Martin (Argentina); Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina); Valda, Alejandro [Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina); Navalesi, Daniela [Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina); Davidson, Jorge; Davidson, Miguel [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Vazquez, Monica; Ozafran, Mabel [Comision Nacional de Energia Atomica, San Martin (Argentina); Duran, Hebe [Comision Nacional de Energia Atomica, San Martin (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin (Argentina)], E-mail: hduran@cnea.gov.ar

2009-07-15T23:59:59.000Z

8

Co-localisation of ?-H2AX and 53BP1 to sites of DNA double strand...  

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

-H2AX and 53BP1 to sites of DNA double strand breaks following low- and high-LET irradiation of mammalian cells Jennifer Anderson, Jane Harper, 1 Frank Cucinotta, 2 Janice...

9

Gene Expression Pathways Activated and Repair of DNA of Double Strand  

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

Pathways Activated and Repair of DNA of Double Strand Pathways Activated and Repair of DNA of Double Strand Breaks (DSBs) Following Low Dose Ionizing Radiation in Human Bronchial Epithelial Cells (HBECs) With and Without Defined Premalignant Oncogenic Changes John Minna University of Texas Southwestern Medical Center at Dallas Abstract We want to determine the effect of low dose ionizing radiation on the molecular progression of lung epithelial cells towards lung cancer. Our endpoints are focused on specific molecular and cellular changes known to be associated with lung cancer development and quantitating those changes as a function of low dose ionizing radiation. We use immortalized human bronchial epithelial cells (HBECs) developed from >40 individuals (including those from current, former, and never smokers, males, females,

10

DNA Double-Strand Break Analysis by {gamma}-H2AX Foci: A Useful Method for Determining the Overreactors to Radiation-Induced Acute Reactions Among Head-and-Neck Cancer Patients  

SciTech Connect

Purpose: Interindividual variability in normal tissue toxicity during radiation therapy is a limiting factor for successful treatment. Predicting the risk of developing acute reactions before initiation of radiation therapy may have the benefit of opting for altered radiation therapy regimens to achieve minimal adverse effects with improved tumor cure. Methods and Materials: DNA double-strand break (DSB) induction and its repair kinetics in lymphocytes of head-and-neck cancer patients undergoing chemoradiation therapy was analyzed by counting {gamma}-H2AX foci, neutral comet assay, and a modified version of neutral filter elution assay. Acute normal tissue reactions were assessed by Radiation Therapy Oncology Group criteria. Results: The correlation between residual DSBs and the severity of acute reactions demonstrated that residual {gamma}-H2AX foci in head-and-neck cancer patients increased with the severity of oral mucositis and skin reaction. Conclusions: Our results suggest that {gamma}-H2AX analysis may have predictive implications for identifying the overreactors to mucositis and skin reactions among head-and-neck cancer patients prior to initiation of radiation therapy.

Goutham, Hassan Venkatesh; Mumbrekar, Kamalesh Dattaram [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India)] [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India); Vadhiraja, Bejadi Manjunath [Manipal Hospital, Bangalore, Karnataka (India)] [Manipal Hospital, Bangalore, Karnataka (India); Fernandes, Donald Jerard; Sharan, Krishna [Department of Radiotherapy and Oncology, Shiridi Sai Baba Cancer Hospital and Research Centre, Kasturba Hospital, Manipal, Karnataka (India)] [Department of Radiotherapy and Oncology, Shiridi Sai Baba Cancer Hospital and Research Centre, Kasturba Hospital, Manipal, Karnataka (India); Kanive Parashiva, Guruprasad; Kapaettu, Satyamoorthy [Division of Biotechnology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India)] [Division of Biotechnology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India); Bola Sadashiva, Satish Rao, E-mail: satishraomlsc@gmail.com [Division of Radiobiology and Toxicology, Manipal Life Sciences Centre, Manipal University, Manipal, Karnataka (India)

2012-12-01T23:59:59.000Z

11

Mechanistic studies of bleomycin-mediated double-stranded DNA cleavage and structural studies of DNA containing normal and 4'-oxidized abasic sites  

E-Print Network (OSTI)

In order to examine the role of partial intercalation in double-stranded (ds) DNA cleavage mediated by a single bleomycin (BLM), a bulky group ([-cyclodextrin) was chemically attached to the polyamine tail of BLM A5 to ...

Chen, Jingyang, Ph. D. Massachusetts Institute of Technology

2006-01-01T23:59:59.000Z

12

ZIP4H (TEX11) Deficiency in the Mouse Impairs Meiotic Double Strand Break Repair and the Regulation of Crossing Over  

E-Print Network (OSTI)

We have recently shown that hypomorphic Mre11 complex mouse mutants exhibit defects in the repair of meiotic double strand breaks (DSBs). This is associated with perturbation of synaptonemal complex morphogenesis, repair and regulation of crossover formation. To further assess the Mre11 complex’s role in meiotic progression, we identified testis-specific NBS1interacting proteins via two-hybrid screening in yeast. In this screen, Zip4h (Tex11), a male germ cell specific X-linked gene was isolated. Based on sequence and predicted structural similarity to the S. cerevisiae and A. thaliana Zip4 orthologs, ZIP4H appears to be the mammalian ortholog. In S. cerevisiae and A. thaliana, Zip4 is a meiosis-specific protein that regulates the level of meiotic crossovers, thus influencing homologous chromosome segregation in these organisms. As is true for hypomorphic Nbs1 (Nbs1 DB/DB) mice, Zip4h 2/Y mutant mice were fertile. Analysis of spermatocytes revealed a delay in meiotic double strand break repair and decreased crossover formation as inferred from DMC1 and MLH1 staining patterns, respectively. Achiasmate chromosomes at the first meiotic division were also observed in Zip4h 2/Y mutants, consistent with the observed reduction in MLH1 focus formation. These results indicate that meiotic functions of Zip4 family members are conserved and support the view that the Mre11 complex and ZIP4H interact functionally during the execution of the

Carrie A. Adelman; John H. J. Petrini

2008-01-01T23:59:59.000Z

13

Dyes designed for high sensitivity detection of double-stranded DNA  

DOE Patents (OSTI)

Novel fluorescent dyes are provided, characterized by having a fluorophore joined to a cationic chain. The dyes are found to provide for high enhancement upon binding to nucleic acid and have strong binding affinities to the nucleic acid, as compared to the fluorophore without the polycationic chain. The dyes find use in detection of dsDNA in gel electrophoresis and solution at substantially higher sensitivities using substantially less dye.

Glazer, Alexander N. (Orinda, CA); Benson, Scott C. (Oakland, CA)

1998-01-01T23:59:59.000Z

14

Dyes designed for high sensitivity detection of double-stranded DNA  

DOE Patents (OSTI)

Novel fluorescent dyes are provided, characterized by having a fluorophore joined to a polycationic chain of at least two positive charges. The dyes are found to provide for high enhancement upon binding to nucleic acid and have strong binding affinities to the nucleic acid, as compared to the fluorophore without the polycationic chain. The dyes find use in detection of dsDNA in gel electrophoresis and solution at substantially higher sensitivities using substantially less dye.

Glazer, Alexander N. (Orinda, CA); Benson, Scott C. (Albany, CA)

1994-01-01T23:59:59.000Z

15

Dyes designed for high sensitivity detection of double-stranded DNA  

DOE Patents (OSTI)

Novel fluorescent dyes are provided, characterized by having a fluorophore joined to a cationic chain. The dyes are found to provide for high enhancement upon binding to nucleic acid and have strong binding affinities to the nucleic acid, as compared to the fluorophore without the polycationic chain. The dyes find use in detection of dsDNA in gel electrophoresis and solution at substantially higher sensitivities using substantially less dye.

Glazer, Alexander N. (Orinda, CA); Benson, Scott C. (Oakland, CA)

2000-01-01T23:59:59.000Z

16

Dyes designed for high sensitivity detection of double-stranded DNA  

DOE Patents (OSTI)

Novel fluorescent dyes are provided, characterized by having a fluorophore joined to a cationic chain. The dyes are found to provide for high enhancement upon binding to nucleic acid and have strong binding affinities to the nucleic acid, as compared to the fluorophore without the polycationic chain. The dyes find use in detection of dsDNA in gel electrophoresis and solution at substantially higher sensitivities using substantially less dye. 10 figs.

Glazer, A.N.; Benson, S.C.

1998-07-21T23:59:59.000Z

17

Homologous recombination contributes to the repair of DNA double-strand breaks induced by high-energy iron ions  

E-Print Network (OSTI)

tightly regulated for doxycycline-inducible shRNA expressioninduced by adding 1 µg/ml doxycycline to the growth mediumfor 16 h (without doxycycline) or 18 h (with doxycycline).

Zafar, Faria

2010-01-01T23:59:59.000Z

18

DNA purification by triplex-affinity capture and affinity capture electrophoresis  

DOE Patents (OSTI)

The invention provides a method for purifying or isolating double stranded DNA intact using triple helix formation. The method includes the steps of complexing an oligonucleotide and double stranded DNA to generate a triple helix and immobilization of the triple helix on a solid phase by means of a molecular recognition system such as avidin/biotin. The purified DNA is then recovered intact by treating the solid phase with a reagent that breaks the bonds between the oligonucleotide and the intact double stranded DNA while not affecting the Watson-Crick base pairs of the double helix. The present invention also provides a method for purifying or isolating double stranded DNA intact by complexing the double stranded DNA with a specific binding partner and recovering the complex during electrophoresis by immobilizing it on a solid phase trap imbedded in an electrophoretic gel. 6 figs.

Cantor, C.R.; Ito, Takashi; Smith, C.L.

1996-01-09T23:59:59.000Z

19

Suberoylanilide Hydroxyamic Acid Modification of Chromatin Architecture Affects DNA Break Formation and Repair  

Science Conference Proceedings (OSTI)

Purpose: Chromatin-modifying compounds that inhibit the activity of histone deacetylases have shown potency as radiosensitizers, but the action of these drugs at a molecular level is not clear. Here we investigated the effect of suberoylanilide hydroxyamic acid (SAHA) on DNA breaks and their repair and induction of rearrangements. Methods and Materials: The effect of SAHA on both clonogenic survival and repair was assessed using cell lines SCC-25, MCF7, and TK6. In order to study unique DNA double-strand breaks, anti-CD95 antibody was employed to introduce a DNA double-strand break at a known location within the 11q23 region. The effects of SAHA on DNA cleavage and rearrangements were analyzed by ligation-mediated PCR and inverse PCR, respectively. Results: SAHA acts as radiosensitizer at 1 {mu}M, with dose enhancement factors (DEFs) at 10% survival of: SCC-25 - 1.24 +- 0.05; MCF7 - 1.16 +- 0.09 and TK6 - 1.17 +- 0.05, and it reduced the capacity of SCC-25 cells to repair radiation induced lesions. Additionally, SAHA treatment diffused site-specific fragmentation over at least 1 kbp in TK6 cells. Chromosomal rearrangements produced in TK6 cells exposed to SAHA showed a reduction in microhomology at the breakpoint between 11q23 and partner chromosomes. Conclusions: SAHA shows efficacy as a radiosensitizer at clinically obtainable levels. In its presence, targeted DNA strand breaks occur over an expanded region, indicating increased chromatin access. The rejoining of such breaks is degraded by SAHA when measured as rearrangements at the molecular level and rejoining that contributes to cell survival.

Singh, Sheetal; Le Hongan; Shih, S.-J.; Ho, Bay [Department of Radiation Oncology, University of California at Davis, 4501 X St., Sacramento, California 95817 (United States); Vaughan, Andrew T., E-mail: andrew.vaughan@ucdmc.ucdavis.ed [Department of Radiation Oncology, University of California at Davis, 4501 X St., Sacramento, California 95817 (United States); Department of Veterans Affairs, Mather, California 95655 (United States)

2010-02-01T23:59:59.000Z

20

Single-nucleotide polymorphisms in base excision repair, nucleotide excision repair, and double strand break genes as markers for response to radiotherapy in patients with Stage I to II head-and-neck cancer  

SciTech Connect

Purpose: Polymorphisms in DNA repair genes can influence response to radiotherapy. We analyzed single-nucleotide polymorphisms (SNP) in nine DNA repair genes in 108 patients with head-and-neck cancer (HNSCC) who had received radiotherapy only. Methods and Materials: From May 1993 to December 2004, patients with Stage I and II histopathologically confirmed HNSCC underwent radiotherapy. DNA was obtained from paraffin-embedded tissue, and SNP analysis was performed using a real-time polymerase chain reaction allelic discrimination TaqMan assay with minor modifications. Results: Patients were 101 men (93.5%) and 7 (6.5%) women, with a median age of 64 years (range, 40 to 89 years). Of the patients, 76 (70.4%) patients were Stage I and 32 (29.6%) were Stage II. The XPF/ERCC1 SNP at codon 259 and XPG/ERCC5 at codon 46 emerged as significant predictors of progression (p 0.00005 and 0.049, respectively) and survival (p = 0.0089 and 0.0066, respectively). Similarly, when variant alleles of XPF/ERCC1, XPG/ERCC5 and XPA were examined in combination, a greater number of variant alleles was associated with shorter time to progression (p = 0.0003) and survival (p 0.0002). Conclusions: Genetic polymorphisms in XPF/ERCC1, XPG/ERCC5, and XPA may significantly influence response to radiotherapy; large studies are warranted to confirm their role in HNSCC.

Carles, Joan [Department of Medical Oncology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain)]. E-mail: jcarles@imas.imim.es; Monzo, Mariano [Department of Human Anatomy, Faculty of Medicine, University of Barcelona, Barcelona (Spain); Amat, Marta [Department of Otolaryngology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain); Jansa, Sonia [Department of Human Anatomy, Faculty of Medicine, University of Barcelona, Barcelona (Spain); Artells, Rosa [Department of Human Anatomy, Faculty of Medicine, University of Barcelona, Barcelona (Spain); Navarro, Alfons [Department of Human Anatomy, Faculty of Medicine, University of Barcelona, Barcelona (Spain); Foro, Palmira [Department of Radiation Oncology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain); Alameda, Francesc [Department of Pathology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain); Gayete, Angel [Department of Radiology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain); Gel, Bernat [Department of Human Anatomy, Faculty of Medicine, University of Barcelona, Barcelona (Spain); Miguel, Maribel [Department of Human Anatomy, Faculty of Medicine, University of Barcelona, Barcelona (Spain); Albanell, Joan [Department of Medical Oncology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain); Fabregat, Xavier [Department of Medical Oncology, Hospital del Mar, University Autonoma of Barcelona, Barcelona (Spain)

2006-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Solid phase sequencing of double-stranded nucleic acids  

DOE Patents (OSTI)

This invention relates to methods for detecting and sequencing of target double-stranded nucleic acid sequences, to nucleic acid probes and arrays of probes useful in these methods, and to kits and systems which contain these probes. Useful methods involve hybridizing the nucleic acids or nucleic acids which represent complementary or homologous sequences of the target to an array of nucleic acid probes. These probe comprise a single-stranded portion, an optional double-stranded portion and a variable sequence within the single-stranded portion. The molecular weights of the hybridized nucleic acids of the set can be determined by mass spectroscopy, and the sequence of the target determined from the molecular weights of the fragments. Nucleic acids whose sequences can be determined include nucleic acids in biological samples such as patient biopsies and environmental samples. Probes may be fixed to a solid support such as a hybridization chip to facilitate automated determination of molecular weights and identification of the target sequence.

Fu, Dong-Jing (Waltham, MA); Cantor, Charles R. (Boston, MA); Koster, Hubert (Concord, MA); Smith, Cassandra L. (Boston, MA)

2002-01-01T23:59:59.000Z

22

Live Cell Imaging and in situ analysis of cellular responses to DNA doublestrand  

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

Live Cell Imaging and in situ analysis of cellular responses to DNA double- Live Cell Imaging and in situ analysis of cellular responses to DNA double- strand breaks in mammalian cells. David J. Chen Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas TX 75390 The integrity of the human genome is constantly threatened by internal as well as external factors with the propensity to cause DNA damage. Of the various types of DNA damage that can occur within the mammalian cell nucleus, the DNA double strand break (DSB) is perhaps the most dangerous. Estimates put the number of endogenous DSBs anywhere between 10-100 per nucleus per day. A direct link between DSBs and cancer has been surmised by researchers based upon the fact that many cancer-predisposition

23

Velocity and processivity of helicase unwinding of double-stranded nucleic acids  

E-Print Network (OSTI)

Helicases are molecular motors which unwind double-stranded nucleic acids (dsNA) in cells. Many helicases move with directional bias on single-stranded (ss) nucleic acids, and couple their directional translocation to strand separation. A model of the coupling between translocation and unwinding uses an interaction potential to represent passive and active helicase mechanisms. A passive helicase must wait for thermal fluctuations to open dsNA base pairs before it can advance and inhibit NA closing. An active helicase directly destabilizes dsNA base pairs, accelerating the opening rate. Here we extend this model to include helicase unbinding from the nucleic-acid strand. The helicase processivity depends on the form of the interaction potential. A passive helicase has a mean attachment time which does not change between ss translocation and ds unwinding, while an active helicase in general shows a decrease in attachment time during unwinding relative to ss translocation. In addition, we describe how helicase u...

Betterton, M D; Julicher, Frank

2005-01-01T23:59:59.000Z

24

Intermediate States of Ribonuclease III in Complex with Double-Stranded RNA  

SciTech Connect

Bacterial ribonuclease III (RNase III) can affect RNA structure and gene expression in either of two ways: as a processing enzyme that cleaves double-stranded (ds) RNA, or as a binding protein that binds but does not cleave dsRNA. We previously proposed a model of the catalytic complex of RNase III with dsRNA based on three crystal structures, including the endonuclease domain of RNase III with and without bound metal ions and a dsRNA binding protein complexed with dsRNA. We also reported a noncatalytic assembly observed in the crystal structure of an RNase III mutant, which binds but does not cleave dsRNA, complexed with dsRNA. We hypothesize that the RNase III {center_dot} dsRNA complex can exist in two functional forms, a catalytic complex and a noncatalytic assembly, and that in between the two forms there may be intermediate states. Here, we present four crystal structures of RNase III complexed with dsRNA, representing possible intermediates.

Gan, Jianhua; Tropea, Joseph E.; Austin, Brian P.; Court, Donald L.; Waugh, David S.; Ji, Xinhua (NIH)

2010-07-19T23:59:59.000Z

25

Velocity and processivity of helicase unwinding of double-stranded nucleic acids  

E-Print Network (OSTI)

Helicases are molecular motors which unwind double-stranded nucleic acids (dsNA) in cells. Many helicases move with directional bias on single-stranded (ss) nucleic acids, and couple their directional translocation to strand separation. A model of the coupling between translocation and unwinding uses an interaction potential to represent passive and active helicase mechanisms. A passive helicase must wait for thermal fluctuations to open dsNA base pairs before it can advance and inhibit NA closing. An active helicase directly destabilizes dsNA base pairs, accelerating the opening rate. Here we extend this model to include helicase unbinding from the nucleic-acid strand. The helicase processivity depends on the form of the interaction potential. A passive helicase has a mean attachment time which does not change between ss translocation and ds unwinding, while an active helicase in general shows a decrease in attachment time during unwinding relative to ss translocation. In addition, we describe how helicase unwinding velocity and processivity vary if the base-pair binding free energy is changed.

M. D. Betterton; Frank Julicher

2005-09-15T23:59:59.000Z

26

Low Dose Radiation Research Program: Assessing Biological Function of DNA  

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

Assessing Biological Function of DNA Damage Response Genes Assessing Biological Function of DNA Damage Response Genes Larry H. Thompson Lawrence Livermore National Laboratory Why This Project To understand the relative importance of individual DNA repair and DNA-damage response pathways to the recovery of mammalian cells after exposure to low doses of ionizing radiation (IR). This understanding may lead to better ways of setting limits on human exposure to IR. In spite of the discovery of many mammalian DNA repair genes, our current knowledge of how many of these genes contribute to cellular recovery from IR exposure is quite limited. Project Goals Measure cellular responses at doses in the 5-100 cGy range, which generally cause changes too small to detect in normal, repair-proficient cells Focus on DNA double-strand breaks (DSBs) and DNA oxidative base

27

Persistent DNA damage foci, cellular senescence and low dose radiation  

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

Persistent DNA damage foci, cellular senescence and low dose radiation Persistent DNA damage foci, cellular senescence and low dose radiation Denise Munoz 1 , Albert Davalos 1 , Francis Rodier 1 , Misako Kawahara 1 , Judith Campisi 1,2 and Steven Yannone 1,3 1 Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 84-171, Berkeley CA 94720; 2 Buck Institute for Age Research, 8001 Redwood Boulevard, Novato CA 94945; 3 Corresponding author Ionizing radiation (IR) induced DNA double-strand breaks (DSBs) are cytologically detectable as large nuclear foci that contain phosphorylated histone H2AX (γH2AX), the adaptor protein 53BP1, and several other proteins that participate in the sensing and processing of DNA damage (DNA damage foci). In normal human cells, moderately high IR (0.5-1 Gy) doses cause the rapid appearance of these foci (acute DNA damage foci), which gradually disappear

28

Breaking  

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

2 Volume 9 Issue 3 2 Volume 9 Issue 3 Closer kin for reference . . . . . . . . . . . . . . . . . . . . . . . 2 Breaking down pulp . . . . . . . . . . . . . . . . . . . . . . . . . 3 Single-cell genomics at the DOE JGI . . . . . . . . . . . . 4 In the news . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7 also in this issue MASSIE SANTOS BALLON The Department of Energy focuses on a variety of alternative energy sources rather than putting all its eggs in one basket. At the recently concluded 7th annual Sequencing, Finishing, Analysis in the Future (SFAF) Meeting held June 5-7, 2012, a similar message came through as speakers discussed combining sequencing platforms and conducting hybrid assemblies to produce more useful data in the form of finished genome sequences. Since the first Sequencing in the Future Meeting held in Santa Fe, New Mexico seven years ago, the number of attendees has increased each year from a starting group of 70, reaching a

29

Mitigating security issues in the evolving DNA synthesis industry  

E-Print Network (OSTI)

DNA synthesis technologies are advancing at exponential rates, with production of ever longer, more complex, and less expensive sequences of double stranded DNA. This has fostered development of industrial scale design, ...

Turlington, Ralph Donald, III

2013-01-01T23:59:59.000Z

30

DNA repair is the target of novel antibiotics  

E-Print Network (OSTI)

Lloyd, (2006) Rep and PriA helicase activities prevent RecAR. G. Lloyd, (2004) RecG helicase promotes DNA double-strandM. A. Petit, (2005) UvrD helicase, unlike Rep helicase,

Gunderson, Carl Wayne

2007-01-01T23:59:59.000Z

31

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

32

Inhibition of Plasmodium falciparum proliferation in vitro by double-stranded RNA directed against malaria histone deacetylase  

SciTech Connect

Acetylation and deacetylation of histones play important roles in transcription regulation, cell cycle progression and development events. The steady state status of histone acetylation is controlled by a dynamic equilibrium between competing histone acetylase and deacetylase (HDAC). We have used long PfHDAC-1 double-stranded (ds)RNA to interfere with its cognate mRNA expression and determined the effect on malaria parasite growth and development. Chloroquine- and pyrimethamine-resistant Plasmodium falciparum K1 strain was exposed to 1-25 {mu}g of dsRNA/ml of culture for 48 h and growth was determined by [{sup 3}H]-hypoxanthine incorporation and microscopic examination. Parasite culture treated with 10 {mu}g/ml pfHDAC-1 dsRNA exhibited 47% growth inhibition when compared with either untreated control or culture treated with an unrelated dsRNA. PfHDAC-1 dsRNA specifically blocked maturation of trophozoite to schizont stages and decreased PfHDAC-1 transcript 44% in treated trophozoites. These results indicate the potential of HDAC-1 as a target for development of novel antimalarials.

Sriwilaijaroen, N. [Faculty of Medicine, Thammasat University (Rangsit Campus), Pathumthani 12120 (Thailand); Boonma, S. [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Attasart, P. [Institute of Molecular Biology and Genetics, Mahidol University, Salaya, Nakornpathom 73170 (Thailand); Pothikasikorn, J. [Department of Microbiology, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Panyim, S. [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Institute of Molecular Biology and Genetics, Mahidol University, Salaya, Nakornpathom 73170 (Thailand); Noonpakdee, W. [Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand)], E-mail: scwnp@mahidol.ac.th

2009-04-03T23:59:59.000Z

33

Hydrogen-bond breaking by O/sub 2/ and N/sub 2/. II. Melting curves of DNA  

DOE Green Energy (OSTI)

Evidence for hydrogen bond breaking (HBB) by O/sub 2/ and N/sub 2/ in the denaturation or melting of DNA is presented. It was found that air and oxygen significantly reduce the temperature of the DNA melting process. The possible relationship of this HBB ability of oxygen and nitrogen to phenomena observed in vivo are discussed. (ACR)

Mathers, T.L.; Schoeffler, G.; McGlynn, S.P.

1982-01-01T23:59:59.000Z

34

Cold atmospheric pressure plasma jets: Interaction with plasmid DNA and tailored electron heating using dual-frequency excitation  

SciTech Connect

Recent progress in plasma science and technology has enabled the development of a new generation of stable cold non-equilibrium plasmas operating at ambient atmospheric pressure. This opens horizons for new plasma technologies, in particular in the emerging field of plasma medicine. These non-equilibrium plasmas are very efficient sources for energy transport through reactive neutral particles (radicals and metastables), charged particles (ions and electrons), UV radiation, and electro-magnetic fields. The effect of a cold radio frequency-driven atmospheric pressure plasma jet on plasmid DNA has been investigated. The formation of double strand breaks correlates well with the atomic oxygen density. Taken with other measurements, this indicates that neutral components in the jet are effective in inducing double strand breaks. Plasma manipulation techniques for controlled energy delivery are highly desirable. Numerical simulations are employed for detailed investigations of the electron dynamics, which determines the generation of reactive species. New concepts based on nonlinear power dissipation promise superior strategies to control energy transport for tailored technological exploitations.

Niemi, K.; O'Neill, C.; Cox, L. J.; Waskoenig, J.; Hyland, W. B.; McMahon, S. J.; Reuter, S.; Currell, F. J.; Graham, W. G.; O'Connell, D.; Gans, T. [Centre for Plasma Physics, Queen's University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom)

2012-05-25T23:59:59.000Z

35

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

36

Low Dose Radiation Research Program: Quantification of Repair...  

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

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells David Schild Lawrence Berkeley National Laboratory Berkeley, California Why this...

37

ExpandplusCrystal Structures of Poly(ADP-ribose) Polymerase-1 (PARP-1) Zinc Fingers Bound to DNA  

Science Conference Proceedings (OSTI)

Poly(ADP-ribose) polymerase-1 (PARP-1) has two homologous zinc finger domains, Zn1 and Zn2, that bind to a variety of DNA structures to stimulate poly(ADP-ribose) synthesis activity and to mediate PARP-1 interaction with chromatin. The structural basis for interaction with DNA is unknown, which limits our understanding of PARP-1 regulation and involvement in DNA repair and transcription. Here, we have determined crystal structures for the individual Zn1 and Zn2 domains in complex with a DNA double strand break, providing the first views of PARP-1 zinc fingers bound to DNA. The Zn1-DNA and Zn2-DNA structures establish a novel, bipartite mode of sequence-independent DNA interaction that engages a continuous region of the phosphodiester backbone and the hydrophobic faces of exposed nucleotide bases. Biochemical and cell biological analysis indicate that the Zn1 and Zn2 domains perform distinct functions. The Zn2 domain exhibits high binding affinity to DNA compared with the Zn1 domain. However, the Zn1 domain is essential for DNA-dependent PARP-1 activity in vitro and in vivo, whereas the Zn2 domain is not strictly required. Structural differences between the Zn1-DNA and Zn2-DNA complexes, combined with mutational and structural analysis, indicate that a specialized region of the Zn1 domain is re-configured through the hydrophobic interaction with exposed nucleotide bases to initiate PARP-1 activation.

M Langelier; J Planck; S Roy; J Pascal

2011-12-31T23:59:59.000Z

38

On the possibility of electronic DNA nanobiochips  

E-Print Network (OSTI)

We have considered as a theoretical possibility for the development of a nanobiochip the operation principle of which is based on measuring conductance in single-stranded and double-stranded DNA. Calculations have demonstrated that in the majority of cases the conductance of double-stranded nucleotides considerably exceeds that of single-stranded ones. The results obtained are in agreement with recent experiments on measuring the oligonucleotide conductance. It has been shown that an electronic biochip containing 11 nucleotide pairs will recognize approximately 97% sequences. It has also been demonstrated that the percentage of identifiable sequences will grow with the sequence length.

Lakhno, V D; 10.1021/ct6003438

2013-01-01T23:59:59.000Z

39

DNA damage produced by exposure of supercoiled plasmid DNA to high- and low-LET ionizing radiation: Effects of hydroxyl radical quenchers. DNA breakage, neutrons, OH radicals  

SciTech Connect

A supercoiled plasmid of 7300 base pairs was isolated and exposed in an aqueous environment to {sup 60}Co {gamma} rays and JANUS 0.85 MeV fission-spectrum neutrons. Dose responses for the production of single-strand breaks (SSBs), double-strand breaks (DSBs) and alkali-labile sites (ALSs) were compared with computations made from the conversion of the supercoil to its relaxed and linear forms. The relative biological effectiveness (RBE) for production of SSBs and DSBs was similar to that previously measured in the cellular environment. The RBE for destruction of genetic transforming activity of M13 viral DNA followed that for DNA damage. This is in contrast to the situation for biological effects such as lethality, mutagenesis, and cellular transformation measured in mammalian cells, where the RBE values are reversed. The role of hydroxyl (OH) radical in DNA damage induction by neutrons was investigated by exposure of plasmid in the presence of known quenchers of this species. Of four quenchers tested, all were able to reduce the yields of both SSBs and DSBs. These findings are consistent with a model for SSB and DSB induction by high linear energy transfer that involves OH radical mediation.

Peak, J.G.; Ito, T.; Peak, M.J. [Argonne National Lab., IL (United States); Robb, F.T. [Univ. of Maryland, Baltimore, MD (United States). Center for Marine Biotechnology

1994-08-01T23:59:59.000Z

40

1999 Gordon Research Conference on Mammalian DNA Repair. Final Progress Report  

SciTech Connect

This Conference will examine DNA repair as the key component in genomic surveillance that is so crucial to the overall integrity and function of mammalian cells. Recent discoveries have catapulted the field of DNA repair into a pivotal position for fundamental investigations into oncology, aging, environmental health, and developmental biology. We hope to highlight the most promising and exciting avenues of research in robust discussions at this conference. This Mammalian DNA Repair Gordon Conference differs from the past conferences in this series, in which the programs were broader in scope, with respect to topics and biological systems covered. A conference sponsored by the Genetics Society in April 1998 emphasized recombinational mechanisms for double-strand break repair and the role of mismatch repair deficiency in colorectal cancer. These topics will therefore receive somewhat less emphasis in the upcoming Conference. In view of the recent mechanistic advances in mammalian DNA repair, an upcoming comprehensive DNA repair meeting next autumn at Hilton Head; and the limited enrollment for Gordon Conferences we have decided to focus session-by-session on particular areas of controversy and/or new developments specifically in mammalian systems. Thus, the principal presentations will draw upon results from other cellular systems only to the extent that they impact our understanding of mammalian DNA repair.

1999-02-12T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

DNA Duplication Revealed in New Beginnings | Department of Energy  

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

DNA Duplication Revealed in New Beginnings DNA Duplication Revealed in New Beginnings DNA Duplication Revealed in New Beginnings April 3, 2012 - 9:36am Addthis The DNA replication origin recognition complex (ORC) is a six-protein machine with a slightly twisted half-ring structure (yellow). ORC is proposed to wrap around and bend approximately 70 base pairs of double stranded DNA (red and blue). When a replication initiator Cdc6 (green) joins ORC, the partial ring is now complete and ready to load another protein onto the DNA. This last protein (not shown) is the enzyme that unwinds the double stranded DNA so each strand can be replicated. | Illustration courtesy of Brookhaven Lab. The DNA replication origin recognition complex (ORC) is a six-protein machine with a slightly twisted half-ring structure (yellow). ORC is

42

Derivatized versions of ligase enzymes for constructing DNA sequences  

DOE Patents (OSTI)

A method of making very long, double-stranded synthetic poly-nucleotides. A multiplicity of short oligonucleotides is provided. The short oligonucleotides are sequentially hybridized to each other. Enzymatic ligation of the oligonucleotides provides a contiguous piece of PCR-ready DNA of predetermined sequence.

Mariella, Jr., Raymond P. (Danville, CA); Christian, Allen T. (Tracy, CA); Tucker, James D. (Novi, MN); Dzenitis, John M. (Livermore, CA); Papavasiliou, Alexandros P. (Oakland, CA)

2006-08-15T23:59:59.000Z

43

Manipulating a single adsorbed DNA for a critical endpoint  

E-Print Network (OSTI)

We show the existence of a critical endpoint in the phase diagram of unzipping of an adsorbed double-stranded (ds) polymer like DNA. The competition of base pairing, adsorption and stretching by an external force leads to the critical end point. From exact results, the location of the critical end point is determined and its classical nature established.

Rajeev Kapri; Somendra M. Bhattacharjee

2008-03-24T23:59:59.000Z

44

Electrophoretic detection and separation of mutant DNA using replaceable polymer matrices  

DOE Patents (OSTI)

The disclosure relates to a method for resolving double-stranded DNA species differing by at least one base pair. Each of the species is characterized by an iso-melting domain with a unique melting temperature contiguous with a melting domain of higher thermal stability. 18 figs.

Karger, B.L.; Thilly, W.G.; Foret, F.; Khrapko, K.; Koehavong, P.; Cohen, A.S.; Giese, R.W.

1997-05-27T23:59:59.000Z

45

Unzipping DNA by force: thermodynamics and finite size behaviour  

E-Print Network (OSTI)

We discuss the thermodynamic behaviour near the force induced unzipping transition of a double stranded DNA in two different ensembles. The Y-fork is identified as the coexisting phases in the fixed distance ensemble. From finite size scaling of thermodynamic quantities like the extensibility, the length of the unzipped segment of a Y-fork, the phase diagram can be recovered. We suggest that such procedures could be used to obtain the thermodynamic phase diagram from experiments on finite length DNA.

Rajeev Kapri; Somendra M. Bhattacharjee

2005-11-22T23:59:59.000Z

46

The effects of bio-fluid on the internal motion of DNA  

E-Print Network (OSTI)

The internal motions of DNA immersed in bio-fluid are investigated. The interactions between the fragments of DNA and the surrounding bio-fluid are modeled using the gauge fluid lagrangian. In the model, the bio-fluid is coupled to the standard gauge invariant bosonic lagrangian describing the DNA. It is shown that at non-relativistic limit various equation of motions, from the well-known Sine-Gordon equation to the simultaneous nonlinear equations, can be constructed within a single framework. The effects of bio-fluid are investigated for two cases : single and double stranded DNA. It is argued that the small and large amplitudes of a single stranded DNA motion immersed in bio-fluid can be explained in a natural way within the model as a solitonic wave regardless with the fluid velocity. In contrary the double stranded DNA behaves as regular or damped harmonic oscillator and is highly depending on the fluid velocity.

Sulaiman, A; 10.1166/jctn.2011.1669

2011-01-01T23:59:59.000Z

47

Hepatitis C virus NS3/4A protein interacts with ATM, impairs DNA repair and enhances sensitivity to ionizing radiation  

Science Conference Proceedings (OSTI)

Hepatitis C virus (HCV) infection is frequently associated with the development of hepatocellular carcinomas and non-Hodgkin's B-cell lymphomas. Nonstructural protein 3 (NS3) of HCV possesses serine protease, nucleoside triphosphatase, and helicase activities, while NS4A functions as a cofactor for the NS3 serine protease. Here, we show that HCV NS3/4A interacts with the ATM (ataxia-telangiectasia mutated), a cellular protein essential for cellular response to irradiation. The expression of NS3/4A caused cytoplasmic translocation of either endogenous or exogenous ATM and delayed dephosphorylation of the phosphorylated ATM and {gamma}-H2AX following ionizing irradiation. As a result, the irradiation-induced {gamma}-H2AX foci persisted longer in the NS3/4A-expressing cells. Furthermore, these cells showed increased comet tail moment in single-cell electrophoresis assay, indicating increased double-strand DNA breaks. The cells harboring an HCV replicon also exhibited cytoplasmic localization of ATM and increased sensitivity to irradiation. These results demonstrate that NS3/4A impairs the efficiency of DNA repair by interacting with ATM and renders the cells more sensitive to DNA damage. This effect may contribute to HCV oncogenesis.

Lai, Chao-Kuen; Jeng, King-Song [Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan (China); Machida, Keigo [Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2001 Zonal Avenue, Los Angeles, CA 90033 (United States); Cheng, Yi-Sheng [Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan (China); Lai, Michael M.C. [Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan (China); Department of Molecular Microbiology and Immunology, University of Southern California, Keck School of Medicine, 2001 Zonal Avenue, Los Angeles, CA 90033 (United States)], E-mail: michlai@gate.sinica.edu.tw

2008-01-20T23:59:59.000Z

48

Histone H2AX participates the DNA damage-induced ATM activation through interaction with NBS1  

SciTech Connect

Phosphorylated histone H2AX ({gamma}-H2AX) functions in the recruitment of DNA damage response proteins to DNA double-strand breaks (DSBs) and facilitates DSB repair. ATM also co-localizes with {gamma}-H2AX at DSB sites following its auto-phosphorylation. However, it is unclear whether {gamma}-H2AX has a role in activation of ATM-dependent cell cycle checkpoints. Here, we show that ATM as well as NBS1 is recruited to damaged-chromatin in a {gamma}-H2AX-dependent manner. Foci formation of phosphorylated ATM and ATM-dependent phosphorylation is repressed in H2AX-knockdown cells. Furthermore, anti-{gamma}-H2AX antibody co-immunoprecipitates an ATM-like protein kinase activity in vitro and recombinant H2AX increases in vitro kinase activity of ATM from un-irradiated cells. Moreover, H2AX-deficient cells exhibited a defect in ATM-dependent cell cycle checkpoints. Taken together, {gamma}-H2AX has important role for effective DSB-dependent activation of ATM-related damage responses via NBS1.

Kobayashi, Junya [Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan)], E-mail: jkobayashi@house.rbc.kyoto-u.ac.jp; Tauchi, Hiroshi [Department of Environmental Sciences, Ibaraki University, Ibaraki 310-8512 (Japan); Chen, Benjamin; Bruma, Sandeep [Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas, Southwestern Medical Center at Dallas, Dallas, TX 75390-9187 (United States); Tashiro, Satoshi [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Matsuura, Shinya [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553 (Japan); Tanimoto, Keiji [Department of Oral and Maxillofacial Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Kasumi 1-2-3, Minami-ku, Hiroshima 734-8553 (Japan); Chen, David J. [Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas, Southwestern Medical Center at Dallas, Dallas, TX 75390-9187 (United States); Komatsu, Kenshi [Department of Genome Repair Dynamics, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan)], E-mail: komatsu@house.rbc.kyoto-u.ac.jp

2009-03-20T23:59:59.000Z

49

Identification of Rad52 complexes reveals a functional link between...  

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

Genetics and Microbiology, MSC08-4660, University of New Mexico School of Medicine, Albuquerque, NM 87131 Rad52 plays important roles in repairing DNA double-strand breaks in...

50

The impact of age, exposure and genetics on homologous recombination at the engineered repeat sequence in mice  

E-Print Network (OSTI)

Mitotic homologous recombination is a critical pathway for the repair of DNA double-strand breaks and broken replication forks. Although homologous recombination is generally error-free, recombination between misaligned ...

Wiktor-Brown, Dominika M

2007-01-01T23:59:59.000Z

51

Effects of garlic on cellular doubling time and DNA strand breaks caused by UV light and BPL, enhanced with catechol and TPA  

Science Conference Proceedings (OSTI)

3T3 cell cultures were exposed to UV light and Beta-Propiolactone. Neoplastic cell transformation (TF) was demonstrated after concurrent addition of catechol, or repeated addition of TPA. Addition of garlic to all fluences/concentrations of the carcinogen/cocarcinogen/promoter groups reduced the number of transformed foci/dish by at least 40%. Since the cell cycle is prolonged following exposure to carcinogens, it is likely the cell requires a longer time to repair this damage. The doubling time (DT) was extended from 12 to 36 hrs. when cells were exposed to BPL and from 12 o 28 hrs. when cells were exposed to 3.0J/M2/sec. If an anticarcinogenic compound is also added, it is reasonable to assume that the cell cycle may be further elongated. The cell cycle, denoted by DT was lengthened from 12 to 47 hrs and from 12 to 86 hrs for BPL and UVC, respectively. The extensions occurred in a dope dependent manner. The concentrations of the cocarcinogen and promoter remained constant throughout the experiment. When strand breaks were determined at the same dose sequences, by alkaline elution, more repair was seen with garlic where the lowest and middle doses of BPL were used and almost no decrease in % DNA eluted was seen with UVC exposed cells. With catechol, there was a two-fold decrease in % DNA eluted at the lowest and middle fluences. When TPA was added, all three fluences of UVC showed more than a threefold decrease in % DNA eluted. BPS with both TPA and catechol, again showed a reduction in strand breaks only low and middle doses. Both a direct-acting alkylating agent, BPL, and a physical carcinogen, UVC, were homogeneously affected, in terms of doubling time, but not when strand break repair was examined. A separate mechanism may be responsible for repair, and the mechanism associated with combinations of physical carcinogen enhancing agents combined with some non-carcinogens may be more profoundly affected by some natural products.

Baturay, N.Z.; Gayle, F.; Liu, S.; Kreidinger, C.

1995-11-01T23:59:59.000Z

52

Helicase on DNA: A Phase coexistence based mechanism  

E-Print Network (OSTI)

We propose a phase coexistence based mechanism for activity of helicases, ubiquitous enzymes that unwind double stranded DNA. The helicase-DNA complex constitutes a fixed-stretch ensemble that entails a coexistence of domains of zipped and unzipped phases of DNA, separated by a domain wall. The motor action of the helicase leads to a change in the position of the fixed constraint thereby shifting the domain wall on dsDNA. We associate this off-equilibrium domain wall motion with the unzipping activity of helicase. We show that this proposal gives a clear and consistent explanation of the main observed features of helicases.

Somendra M. Bhattacharjee; Flavio Seno

2002-05-13T23:59:59.000Z

53

The human actin-related protein hArp5: Nucleo-cytoplasmic shuttling and involvement in DNA repair  

Science Conference Proceedings (OSTI)

Certain actin-related proteins (Arps) of budding yeast are localized in the nucleus, and have essential roles as stoichiometric components of histone acetyltransferase (HAT) and chromatin remodeling complexes. On the other hand, identification of vertebrate nuclear Arps and their functional analyses are just beginning. We show that human Arp5 (hArp5) proteins are localized in the nucleus, and that arp5{delta} yeast cells are partially complemented by hArp5. Thus, hArp5 is a novel member of the nuclear Arps of vertebrates, which possess evolutionarily conserved functions from yeast to humans. We show here that hArp5 shuttles between the nucleus and the cytoplasm. Furthermore, after the induction of DNA double strand breaks (DSB), cell growth and the accumulation of phosphorylated histone H2AX ({gamma}-H2AX) are impaired by hArp5 depletion. Association of hArp5 with the hIno80 chromatin remodeling enzyme and decrease of chromatin-bound hIno80 by hArp5-depletion indicate that hArp5 may have a role in the recruitment of the hINO80 complex to chromatin. Overexpression of hArp5 and hIno80 enhanced {gamma}-H2AX accumulation. These observations suggest that hArp5 is involved in the process of DSB repair through the regulation of the chromatin remodelling machinery.

Kitayama, Kumiko; Kamo, Mariko [Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Tsutsumidori-Amamiyamachi 1-1, Aoba-ku, Sendai 981-8555 (Japan); Oma, Yukako [Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Tsutsumidori-Amamiyamachi 1-1, Aoba-ku, Sendai 981-8555 (Japan); Department of Molecular and Cellular Genetics, UMR7156 CNRS-ULP, University of Strasbourg, 67084 Strasbourg cedex (France); Matsuda, Ryo [Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Tsutsumidori-Amamiyamachi 1-1, Aoba-ku, Sendai 981-8555 (Japan); Uchida, Takafumi [Enzymology, Graduate School of Agricultural, Tohoku University, Tsutsumidori-Amamiyamachi 1-1, Aoba-ku, Sendai 981-8555 (Japan); Ikura, Tsuyoshi [Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryoumachi 2 2-1, Aoba-ku, Sendai 980-8575 (Japan); Tashiro, Satoshi [Department of Cellular Biology, Hiroshima University, Hiroshima 734-8553 (Japan); Ohyama, Takashi [Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480 (Japan); Winsor, Barbara [Department of Molecular and Cellular Genetics, UMR7156 CNRS-ULP, University of Strasbourg, 67084 Strasbourg cedex (France); Harata, Masahiko [Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Tsutsumidori-Amamiyamachi 1-1, Aoba-ku, Sendai 981-8555 (Japan)], E-mail: mharata@biochem.tohoku.ac.jp

2009-01-15T23:59:59.000Z

54

A model for DNA helicase mechanism based on a flashing ratchet  

E-Print Network (OSTI)

Helicases are molecular motors that consume energy supplied by chemical reactions to unwind double-stranded nucleic acids (like DNA and RNA) and to translocate along one of the single-strands. Motivated by the recent claims, based on experimental observations on the helicase NS3 of hepatitis C virus (HCV), that monomeric helicases are governed by a Brownian ratchet mechanism, here we develope a quantitative model. Our Brownian ratchet model, which is a somewhat new reformulation of the Betterton-J\\"ulicher theory of helicases, is generic two-state model and is applicable to all helicases which follow the Brownian ratchet mechanism. We illustrate the predictive power of the model by calculating some experimentally testable motor properties of a few monomeric helicases. Speficically, we predict the speed of unwinding of the double-stranded DNA and fluctuations around the average drift of the helicase. Our predictions are in excellent quantitative agreement with the corresponding experimental data.

Garai, Ashok; Chowdhury, Debashish

2007-01-01T23:59:59.000Z

55

Helicase activity on DNA as a propagating front  

E-Print Network (OSTI)

We develop a propagating front analysis, in terms of a local probability of zipping, for the helicase activity of opening up a double stranded DNA (dsDNA). In a fixed-distance ensemble (conjugate to the fixed-force ensemble) the front separates the zipped and unzipped phases of a dsDNA and a drive acts locally around the front. Bounds from variational analysis and numerical estimates for the speed of a helicase are obtained. Different types of helicase behaviours can be distinguished by the nature of the drive.

Somendra M. Bhattacharjee

2003-07-16T23:59:59.000Z

56

Rapid purification of circular DNA by triplex-mediated affinity capture  

DOE Patents (OSTI)

A single-step capture of a target supercoiled double-stranded DNA molecule is accomplished by forming a local triple-helix among two strands of the supercoiled circular DNA and an oligonucleotide probe. The oligonucleotide is bound to an immobilizing support which facilitates the immobilization and purification of target DNA molecules. Non-target DNA molecules and other contaminating cellular material are easily removed by washing. The triple-helical structure is destabilized by raising the pH, leaving purified target DNA in the supernatant and reusable affinity capture oligonucleotide secured to the immobilizing support.

Ji, Huamin (4817 Sheboygan Ave., Madison, WI 53705); Smith, Lloyd M. (1115 Amherst Dr., Madison, WI 53705)

1997-01-01T23:59:59.000Z

57

Rapid purification of circular DNA by triplex-mediated affinity capture  

DOE Patents (OSTI)

A single-step capture of a target supercoiled double-stranded DNA molecule is accomplished by forming a local triple-helix among two strands of the supercoiled circular DNA and an oligonucleotide probe. The oligonucleotide is bound to an immobilizing support which facilitates the immobilization and purification of target DNA molecules. Non-target DNA molecules and other contaminating cellular material are easily removed by washing. The triple-helical structure is destabilized by raising the pH, leaving purified target DNA in the supernatant and reusable affinity capture oligonucleotide secured to the immobilizing support. 3 figs.

Ji, H.; Smith, L.M.

1997-01-07T23:59:59.000Z

58

WHERE MULTIFUNCTIONAL DNA REPAIR PROTEINS MEET: MAPPING THE INTERACTION DOMAINS BETWEEN XPG AND WRN  

Science Conference Proceedings (OSTI)

The rapid recognition and repair of DNA damage is essential for the maintenance of genomic integrity and cellular survival. Multiple complex and interconnected DNA damage responses exist within cells to preserve the human genome, and these repair pathways are carried out by a specifi c interplay of protein-protein interactions. Thus a failure in the coordination of these processes, perhaps brought about by a breakdown in any one multifunctional repair protein, can lead to genomic instability, developmental and immunological abnormalities, cancer and premature aging. This study demonstrates a novel interaction between two such repair proteins, Xeroderma pigmentosum group G protein (XPG) and Werner syndrome helicase (WRN), that are both highly pleiotropic and associated with inherited genetic disorders when mutated. XPG is a structure-specifi c endonuclease required for the repair of UV-damaged DNA by nucleotide excision repair (NER), and mutations in XPG result in the diseases Xeroderma pigmentosum (XP) and Cockayne syndrome (CS). A loss of XPG incision activity results in XP, whereas a loss of non-enzymatic function(s) of XPG causes CS. WRN is a multifunctional protein involved in double-strand break repair (DSBR), and consists of 3’–5’ DNA-dependent helicase, 3’–5’ exonuclease, and single-strand DNA annealing activities. Nonfunctional WRN protein leads to Werner syndrome, a premature aging disorder with increased cancer incidence. Far Western analysis was used to map the interacting domains between XPG and WRN by denaturing gel electrophoresis, which separated purifi ed full length and recombinant XPG and WRN deletion constructs, based primarily upon the length of each polypeptide. Specifi c interacting domains were visualized when probed with the secondary protein of interest which was then detected by traditional Western analysis using the antibody of the secondary protein. The interaction between XPG and WRN was mapped to the C-terminal region of XPG as well as the C-terminal region of WRN. The physical interaction between XPG and WRN links NER, (made evident by the disease XP) with DSBR, which imparts additional knowledge of the overlapping nature of these two proteins and the previously distinct DNA repair pathways they are associated with. Since genomic integrity is constantly threatened by both endogenous and exogenous (internal and external) damage, understanding the roles of these proteins in coordinating DNA repair processes with replication will signifi cantly further understanding how defects instigate physiological consequences in response to various DNA damaging sources. This ultimately contributes to our understanding of cancer and premature aging.

Rangaraj, K.; Cooper, P.K.; Trego, K.S.

2009-01-01T23:59:59.000Z

59

The Boltzmann factor, DNA melting, and Brownian ratchets: Topics in an introductory physics sequence for biology and premedical students  

E-Print Network (OSTI)

Three, interrelated biologically-relevant examples of biased random walks are presented: (1) A model for DNA melting, modelled as DNA unzipping, which provides a way to illustrate the role of the Boltzmann factor in a venue well-known to biology and pre-medical students; (2) the activity of helicase motor proteins in unzipping double-stranded DNA, for example, at the replication fork, which is an example of a Brownian ratchet; (3) force generation by actin polymerization, which is another Brownian ratchet, and for which the force and actin-concentration dependence of the velocity of actin polymerization is determined.

Mochrie, S G J

2011-01-01T23:59:59.000Z

60

Low Dose Radiation Research Program: Quantification of Repair of  

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

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells Authors: David Schild,1 and Larry H. Thompson,2 Institutions: 1Life Sciences Division, Lawrence Berkeley National Laboratory; and 2BBR Program, Lawrence Livermore National Laboratory Double-strand breaks (DSBs) are the biochemical lesions of primary concern in radiation related health effects. Compelling evidence from rodent and chicken model systems indicates that homologous recombinational repair (HRR) plays an essential role for cell viability in the repair of spontaneous DSBs arising during DNA replication and an important role in the repair of IR-induced DSBs. IR-induced DSBs are also repaired by error-prone nonhomologous end joining (NHEJ). Using hTERT-immortalized

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


61

DNA  

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

directed directed assembly of nanoparticle linear structure for nanophotonics Baoquan Ding, aÍ’ Stefano Cabrini, bÍ’ Ronald N. Zuckermann, and Jeffrey Bokor Molecular Foundry, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, California 94720 Í‘Received 17 June 2008; accepted 22 December 2008; published 2 February 2009Í’ Assemblies of metal nanospheres have shown interesting properties for nanophotonics. Here the authors describe a method to use robust DNA multicrossover molecules to organize Au nanoparticles with different sizes to form well controlled linear chain structures with desired distance below 10 nm between the particles. Au particles with only one piece of DNA attached are purified individually. Three different sizes DNA-Au conjugates then hybridize with five other DNA strands to form the stiff triple crossover Í‘TXÍ’ motif. The linkage position

62

DNA Sequencing Using capillary Electrophoresis  

Science Conference Proceedings (OSTI)

The overall goal of this program was to develop capillary electrophoresis as the tool to be used to sequence for the first time the Human Genome. Our program was part of the Human Genome Project. In this work, we were highly successful and the replaceable polymer we developed, linear polyacrylamide, was used by the DOE sequencing lab in California to sequence a significant portion of the human genome using the MegaBase multiple capillary array electrophoresis instrument. In this final report, we summarize our efforts and success. We began our work by separating by capillary electrophoresis double strand oligonucleotides using cross-linked polyacrylamide gels in fused silica capillaries. This work showed the potential of the methodology. However, preparation of such cross-linked gel capillaries was difficult with poor reproducibility, and even more important, the columns were not very stable. We improved stability by using non-cross linked linear polyacrylamide. Here, the entangled linear chains could move when osmotic pressure (e.g. sample injection) was imposed on the polymer matrix. This relaxation of the polymer dissipated the stress in the column. Our next advance was to use significantly lower concentrations of the linear polyacrylamide that the polymer could be automatically blown out after each run and replaced with fresh linear polymer solution. In this way, a new column was available for each analytical run. Finally, while testing many linear polymers, we selected linear polyacrylamide as the best matrix as it was the most hydrophilic polymer available. Under our DOE program, we demonstrated initially the success of the linear polyacrylamide to separate double strand DNA. We note that the method is used even today to assay purity of double stranded DNA fragments. Our focus, of course, was on the separation of single stranded DNA for sequencing purposes. In one paper, we demonstrated the success of our approach in sequencing up to 500 bases. Other application papers of sequencing up to this level were also published in the mid 1990's. A major interest of the sequencing community has always been read length. The longer the sequence read per run the more efficient the process as well as the ability to read repeat sequences. We therefore devoted a great deal of time to studying the factors influencing read length in capillary electrophoresis, including polymer type and molecule weight, capillary column temperature, applied electric field, etc. In our initial optimization, we were able to demonstrate, for the first time, the sequencing of over 1000 bases with 90% accuracy. The run required 80 minutes for separation. Sequencing of 1000 bases per column was next demonstrated on a multiple capillary instrument. Our studies revealed that linear polyacrylamide produced the longest read lengths because the hydrophilic single strand DNA had minimal interaction with the very hydrophilic linear polyacrylamide. Any interaction of the DNA with the polymer would lead to broader peaks and lower read length. Another important parameter was the molecular weight of the linear chains. High molecular weight (> 1 MDA) was important to allow the long single strand DNA to reptate through the entangled polymer matrix. In an important paper, we showed an inverse emulsion method to prepare reproducibility linear polyacrylamide polymer with an average MWT of 9MDa. This approach was used in the polymer for sequencing the human genome. Another critical factor in the successful use of capillary electrophoresis for sequencing was the sample preparation method. In the Sanger sequencing reaction, high concentration of salts and dideoxynucleotide remained. Since the sample was introduced to the capillary column by electrokinetic injection, these salt ions would be favorably injected into the column over the sequencing fragments, thus reducing the signal for longer fragments and hence reading read length. In two papers, we examined the role of individual components from the sequencing reaction and then developed a protocol to reduce the deleterio

Dr. Barry Karger

2011-05-09T23:59:59.000Z

63

Mutations Altering the Interplay between GkDnaC Helicase and DNA Reveal an Insight into Helicase Unwinding  

E-Print Network (OSTI)

Replicative helicases are essential molecular machines that utilize energy derived from NTP hydrolysis to move along nucleic acids and to unwind double-stranded DNA (dsDNA). Our earlier crystal structure of the hexameric helicase from Geobacillus kaustophilus HTA426 (GkDnaC) in complex with single-stranded DNA (ssDNA) suggested several key residues responsible for DNA binding that likely play a role in DNA translocation during the unwinding process. Here, we demonstrated that the unwinding activities of mutants with substitutions at these key residues in GkDnaC are 2–4-fold higher than that of wildtype protein. We also observed the faster unwinding velocities in these mutants using single-molecule experiments. A partial loss in the interaction of helicase with ssDNA leads to an enhancement in helicase efficiency, while their ATPase activities remain unchanged. In strong contrast, adding accessory proteins (DnaG or DnaI) to GkDnaC helicase alters the ATPase, unwinding efficiency and the unwinding velocity of the helicase. It suggests that the unwinding velocity of helicase

Yu-hua Lo; Shih-wei Liu; Yuh-ju Sun; Hung-wen Lizz; Chwan-deng Hsiao

2011-01-01T23:59:59.000Z

64

Weakly Charged Cationic Nanoparticles Induce DNA Bending and Strand Separation  

SciTech Connect

The understanding of interactions between double stranded (ds) DNA and charged nanoparticles will have a broad bearing on many important applications from drug delivery [ 1 4 ] to DNAtemplated metallization. [ 5 , 6 ] Cationic nanoparticles (NPs) can bind to DNA, a negatively charged molecule, through a combination of electrostatic attraction, groove binding, and intercalation. Such binding events induce changes in the conformation of a DNA strand. In nature, DNA wraps around a cylindrical protein assembly (diameter and height of 6 nm) [ 7 ] with an 220 positive charge, [ 8 ] creating the complex known as chromatin. Wrapping and bending of DNA has also been achieved in the laboratory through the binding of highly charged species such as molecular assemblies, [ 9 , 10 ] cationic dendrimers, [ 11 , 12 ] and nanoparticles. [ 13 15 ] The charge of a nanoparticle plays a crucial role in its ability to induce DNA structural changes. If a nanoparticle has a highly positive surface charge density, the DNA is likely to wrap and bend upon binding to the nanoparticle [ 13 ] (as in the case of chromatin). On the other hand, if a nanoparticle is weakly charged it will not induce dsDNA compaction. [ 9 , 10 , 15 ] Consequently, there is a transition zone from extended to compact DNA conformations which depends on the chemical nature of the nanoparticle and occurs for polycations with charges between 5 and 10. [ 9 ] While the interactions between highly charged NPs and DNA have been extensively studied, the processes that occur within the transition zone are less explored.

Railsback, Justin [North Carolina State University; Singh, Abhishek [North Carolina State University; Pearce, Ryan [North Carolina State University; McKnight, Timothy E [ORNL; Collazo, Ramon [North Carolina State University; Sitar, Zlatko [ORNL; Yingling, Yaroslava [North Carolina State University; Melechko, Anatoli Vasilievich [ORNL

2012-01-01T23:59:59.000Z

65

Lorentz Breaking and Gravity  

E-Print Network (OSTI)

Gravitational theories with Lorentz violation must account for a number of possible features in order to be consistent theoretically and phenomenologically. A brief summary of these features is given here. They include evasion of a no-go theorem, connections between spontaneous Lorentz breaking and diffeomorphism breaking, the appearance of massless Nambu-Goldstone modes and massive Higgs modes, and the possibility of a Higgs mechanism in gravity.

R. Bluhm

2013-07-22T23:59:59.000Z

66

Binary electrokinetic separation of target DNA from background DNA primers.  

Science Conference Proceedings (OSTI)

This report contains the summary of LDRD project 91312, titled ''Binary Electrokinetic Separation of Target DNA from Background DNA Primers''. This work is the first product of a collaboration with Columbia University and the Northeast BioDefense Center of Excellence. In conjunction with Ian Lipkin's lab, we are developing a technique to reduce false positive events, due to the detection of unhybridized reporter molecules, in a sensitive and multiplexed detection scheme for nucleic acids developed by the Lipkin lab. This is the most significant problem in the operation of their capability. As they are developing the tools for rapidly detecting the entire panel of hemorrhagic fevers this technology will immediately serve an important national need. The goal of this work was to attempt to separate nucleic acid from a preprocessed sample. We demonstrated the preconcentration of kilobase-pair length double-stranded DNA targets, and observed little preconcentration of 60 base-pair length single-stranded DNA probes. These objectives were accomplished in microdevice formats that are compatible with larger detection systems for sample pre-processing. Combined with Columbia's expertise, this technology would enable a unique, fast, and potentially compact method for detecting/identifying genetically-modified organisms and multiplexed rapid nucleic acid identification. Another competing approach is the DARPA funded IRIS Pharmaceutical TIGER platform which requires many hours for operation, and an 800k$ piece of equipment that fills a room. The Columbia/SNL system could provide a result in 30 minutes, at the cost of a few thousand dollars for the platform, and would be the size of a shoebox or smaller.

James, Conrad D.; Derzon, Mark Steven

2005-10-01T23:59:59.000Z

67

Structural Analysis of Rtt106p Reveals a DNA Binding Role Required for Heterochromatin Silencing  

Science Conference Proceedings (OSTI)

Rtt106p is a Saccharomyces cerevisiae histone chaperone with roles in heterochromatin silencing and nucleosome assembly. The molecular mechanism by which Rtt106p engages in chromatin dynamics remains unclear. Here, we report the 2.5 {angstrom} crystal structure of the core domain of Rtt106p, which adopts an unusual 'double pleckstrin homology' domain architecture that represents a novel structural mode for histone chaperones. A histone H3-H4-binding region and a novel double-stranded DNA-binding region have been identified. Mutagenesis studies reveal that the histone and DNA binding activities of Rtt106p are involved in Sir protein-mediated heterochromatin formation. Our results uncover the structural basis of the diverse functions of Rtt106p and provide new insights into its cellular roles.

Liu, Y.; Huang, H; Zhou, B; Wang, S; Hu, Y; Li, X; Liu, J; Niu, L; Wu, J; et. al.

2010-01-01T23:59:59.000Z

68

Chapter 11 Forecasting breaks and forecasting during breaks  

E-Print Network (OSTI)

Success in accurately forecasting breaks requires that they are predictable from relevant information available at the forecast origin using an appropriate model form, which can be selected and estimated before the break. To clarify the roles of these six necessary conditions, we distinguish between the information set for ‘normal forces ’ and the one for ‘break drivers’, then outline sources of potential information. Relevant non-linear, dynamic models facing multiple breaks can have more candidate variables than observations, so we discuss automatic model selection. As a failure to accurately forecast breaks remains likely, we augment our strategy by modelling breaks during their progress, and consider robust forecasting devices.

Jennifer L. Castle; Nicholas W. P. Fawcett; David F. Hendry

2011-01-01T23:59:59.000Z

69

$R$-Parity Breaking Phenomenology  

E-Print Network (OSTI)

We review various features of the $R$-parity breaking phenomenology, with particular attention to the low energy observables, and to the patterns of the $R$-parity breaking interactions that arise in Grand Unified models.

Francesco Vissani

1996-02-26T23:59:59.000Z

70

Diffusive Transport by Breaking Waves  

Science Conference Proceedings (OSTI)

A simple conceptual model of the relationship between advective transport by breaking waves and diffusive transport is derived. line model postulates that the displacement of fluid parcels by a breaking wave is analogous to molecular diffusion (...

Kenneth P. Bowman

1995-07-01T23:59:59.000Z

71

Breaking Down the Barriers  

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

Breaking Down the Barriers Breaking Down the Barriers Engaging Agency Legal Resources to be Part of the Solution Daniel Gore US Coast Guard Energy Manager X ESPC ISC Kodiak ESPC/UESC Unit Contract Type Coast Guard Alternatively Financed Project Status Estimated Contract Value (Millions) Under Consideration Initial Proposal Delayed by lack of Contracting Officer or Champion Detailed Design Study Recently Awarded TRACEN Cape May ESPC X TRACEN Petaluma PPA X X ISC San Pedro UESC X X CG Academy ESPC X TRACEN Cape May UESC X Air Station Borenquin ESPC X X Sector New York (3 sites) ESPC X X CG Yard (BAMF) ESPC X E-City ESPC X West Coast - 9 Sites ESPC X Five Essentials for Alt. Financed Project * Site approval * Technical Champion * Contracting Officer * Financial Analyst * Legal Support

72

Energy Loss by Breaking waves  

Science Conference Proceedings (OSTI)

Observations of the frequency of wind wave breaking in deep water are combined with laboratory estimates of the rate of energy loss a from single breaking wave to infer the net rate of energy transfer to the mixed layer from breaking waves, as a ...

S. A. Thorpe

1993-11-01T23:59:59.000Z

73

Gravitational Waves from Supersymmetry Breaking  

E-Print Network (OSTI)

In theories of supersymmetry breaking, it is often the case that there is more than one metastable vacuum. First-order phase transitions among such metastable vacua may generate a stochastic background of gravitational waves, the observation of which would provide a direct window into the supersymmetry-breaking sector.

Craig, Nathaniel J

2009-01-01T23:59:59.000Z

74

Nanowire Micronetworks from Carbon-Black Nanoparticles | Advanced Photon  

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

A Key Step in Repairing DNA Double-Strand Breaks A Key Step in Repairing DNA Double-Strand Breaks An X-ray Rainbow An Insulating Breakthrough 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 Nanowire Micronetworks from Carbon-Black Nanoparticles JANUARY 11, 2007 Bookmark and Share Fig. 1. Diagram showing CB segregation to triple junctions during press sintering. Inset: USAXS image acquired from a press-sintered CB/PMMA sample with 1% CB mass fraction. Self-assembly is likely to play a decisive role in producing nanoscale elements for three dimensional (3D) electronic and nanoscale electro-mechanical systems. Until now, however, the difficult problem of fabricating a complex, interconnected 3D system of conductive nanoscale

75

Global methylation responses to low dose radiation exposure  

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

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

76

Low Dose Radiation Research Program Publications  

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

for medical exposures. Environmental and Molecular Mutagenesis 53(4): 247259 Lynn Hlatky ( 2012) Double-Strand Break Motions Shift Radiation Risk Notions?. PNAS...

77

R parity can spontaneously break  

E-Print Network (OSTI)

We refute the claims made by Chaichian and Smilga in a recent paper in Phys Rev Letters on the impossibility of spontaneous R Parity breaking. Apart from explaining their error we summarize the results of a more detailed work that demonstrates explicitly that R parity can break spontaneously at a scale anywhere in the range 10 GeV to 1 Tev in a simple extension of the minimal SUSY standard model proposed previously.

J C Romao; C A Santos; J W F Valle

1992-05-06T23:59:59.000Z

78

The T4 Phage SF1B Helicase Dda Is Structurally Optimized to Perform DNA Strand Separation  

Science Conference Proceedings (OSTI)

Helicases move on DNA via an ATP binding and hydrolysis mechanism coordinated by well-characterized helicase motifs. However, the translocation along single-stranded DNA (ssDNA) and the strand separation of double-stranded (dsDNA) may be loosely or tightly coupled. Dda is a phage T4 SF1B helicase with sequence homology to the Pif1 family of helicases that tightly couples translocation to strand separation. The crystal structure of the Dda-ssDNA binary complex reveals a domain referred to as the pin that was previously thought to remain static during strand separation. The pin contains a conserved phenylalanine that mediates a transient base-stacking interaction that is absolutely required for separation of dsDNA. The pin is secured at its tip by protein-protein interactions through an extended SH3 domain thereby creating a rigid strut. The conserved interface between the pin and the SH3 domain provides the mechanism for tight coupling of translocation to strand separation.

He, Xiaoping; Byrd, Alicia K.; Yun, Mi-Kyung; Pemble IV, Charles W.; Harrison, David; Yeruva, Laxmi; Dahl, Christopher; Kreuzer, Kenneth N.; Raney, Kevin D.; White, Stephen W. (Duke); (SJCH); (Arkansas)

2012-10-16T23:59:59.000Z

79

Line narrowing spectroscopic studies of DNA-carcinogen adducts and DNA-dye complexes  

Science Conference Proceedings (OSTI)

Laser-induced fluorescence line narrowing and non-line narrowing spectroscopic methods were applied to conformational studies of stable DNA adducts of the 7{beta}, 8{alpha}-dihydoxy-9{alpha}, l0{alpha}-epoxy-7,8,9, 10-tetrahydrobenzo[{alpha}]pyrene (anti-BPDE). Stereochemically distinct (+)-trans-, ({minus})-trans-, (+)-cis- and ({minus})-cis adducts of anti-BPDE bound to exocyclic amino group of the central guanine in an 11-mer oligonucleotide, exist in a mixture of conformations in frozen aqueous buffer matrices. The (+)-trans adduct adopts primarily an external conformation with a smaller fraction ( {approximately} 25 %) exists in a partially base-stacked conformation. Both cis adducts were found to be intercalated with significant {pi}-{pi} stacking interactions between the pyrenyl residues and the bases. Conformations of the trans-adduct of (+)-anti -BPDE in 11-mer oligonucleotides were studied as a function of flanking bases. In single stranded form the adduct at G{sub 2} or G{sub 3} (5 ft-flanking, base guanine) adopts a conformation with strong, interaction with the bases. In contrast, the adduct with a 5ft-flanking, thymine exists in a primarily helixexternal conformation. Similar differences were observed in the double stranded oligonucleotides. The nature of the 3ft-flanking base has little influence on the conformational equilibrium of the (+)-trans-anti BPDE-dG adduct. The formation and repair of BPDE-N{sup 2}-dG in DNA isolated from the skin of mice treated topically with benzo[{alpha}]pyrene (BP) was studied. Low-temperature fluorescence spectroscopy of the intact DNA identified the major adduct as (+)-trans-anti-BPDE-N-dG, and the minor adduct fraction consisted mainly of (+)-cis-anti-BPDE-N{sup 2}-dG.

Suh, Myungkoo

1995-12-06T23:59:59.000Z

80

NERSC's Hopper Breaks Petaflops Barrier  

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

NERSC's Hopper Breaks NERSC's Hopper Breaks Petaflops Barrier NERSC's Hopper Breaks Petaflops Barrier Ranks 5th in the World November 14, 2010 Media Contact: Jon Bashor, jbashor@lbl.gov, 510-486-5849 hopper1.jpg NERSC's Cray XE6-Hopper BERKELEY, Calif.-The Department of Energy's National Energy Research Scientific Computing Center (NERSC), already one of the world's leading centers for scientific productivity, is now home to the fifth most powerful supercomputer in the world and the second most powerful in the United States, according to the latest edition of the TOP500 list, the definitive ranking of the world's top computers NERSC's newest supercomputer, a 153,408 processor-core Cray XE6 system, posted a performance of 1.05 petaflops (quadrillions of calculations per second) running the Linpack benchmark. In keeping with NERSC's tradition of

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Chiral Symmetry Breaking in Graphene  

E-Print Network (OSTI)

The question of whether the Coulomb interaction is strong enough to break the sublattice symmetry of un-doped graphene is discussed. We formulate a strong coupling expansion where the ground state of the Coulomb Hamiltonian is found exactly and the kinetic hopping Hamiltonian is treated as a perturbation. We argue that many of the properties of the resulting system would be shared by graphene with a Hubbard model interaction. In particular, the best candidate sublattice symmetry breaking ground state is an antiferromagnetic Mott insulator. We discuss the results of some numerical simulations which indicate that the Coulomb interaction is indeed subcritical. We also point out the curious fact that, if the electron did not have spin degeneracy, the tendency to break chiral symmetry would be much greater and even relatively weak Coulomb interactions would likely gap the spectrum.

Gordon W. Semenoff

2011-08-15T23:59:59.000Z

82

Etoposide Metabolites Enhance DNA Topoisomerase II Cleavage near Leukemia-Associated MLL Translocation Breakpoints †  

E-Print Network (OSTI)

ABSTRACT: Chromosomal breakage resulting from stabilization of DNA topoisomerase II covalent complexes by epipodophyllotoxins may play a role in the genesis of leukemia-associated MLL gene translocations. We investigated whether etoposide catechol and quinone metabolites can damage the MLL breakpoint cluster region in a DNA topoisomerase II-dependent manner like the parent drug and the nature of the damage. Cleavage of two DNA substrates containing the normal homologues of five MLL intron 6 translocation breakpoints was examined in vitro upon incubation with human DNA topoisomerase IIR, ATP, and either etoposide, etoposide catechol, or etoposide quinone. Many of the same cleavage sites were induced by etoposide and by its metabolites, but several unique sites were induced by the metabolites. There was a preference for G(-1) among the unique sites, which differs from the parent drug. Cleavage at most sites was greater and more heat-stable in the presence of the metabolites compared to etoposide. The MLL translocation breakpoints contained within the substrates were near strong and/or stable cleavage sites. The metabolites induced more cleavage than etoposide at the same sites within a 40 bp double-stranded oligonucleotide containing two of the translocation breakpoints, confirming the results

Brian D. Lovett; Dirk Strumberg; Ian A. Blair; Shaokun Pang; O Donald; A. Burden; Maureen D. Megonigal; Timothy R. Rebbeck; Neil Osheroff; Yves G. Pommier; Carolyn A. Felix

2000-01-01T23:59:59.000Z

83

Rotations of the 2B Sub-domain of E. coli UvrD Helicase/Translocase Coupled to Nucleotide and DNA Binding  

Science Conference Proceedings (OSTI)

Escherichia coli UvrD is a superfamily 1 DNA helicase and single-stranded DNA (ssDNA) translocase that functions in DNA repair and plasmid replication and as an anti-recombinase by removing RecA protein from ssDNA. UvrD couples ATP binding and hydrolysis to unwind double-stranded DNA and translocate along ssDNA with 3'-to-5' directionality. Although a UvrD monomer is able to translocate along ssDNA rapidly and processively, DNA helicase activity in vitro requires a minimum of a UvrD dimer. Previous crystal structures of UvrD bound to a ssDNA/duplex DNA junction show that its 2B sub-domain exists in a 'closed' state and interacts with the duplex DNA. Here, we report a crystal structure of an apo form of UvrD in which the 2B sub-domain is in an 'open' state that differs by an {approx} 160{sup o} rotation of the 2B sub-domain. To study the rotational conformational states of the 2B sub-domain in various ligation states, we constructed a series of double-cysteine UvrD mutants and labeled them with fluorophores such that rotation of the 2B sub-domain results in changes in fluorescence resonance energy transfer. These studies show that the open and closed forms can interconvert in solution, with low salt favoring the closed conformation and high salt favoring the open conformation in the absence of DNA. Binding of UvrD to DNA and ATP binding and hydrolysis also affect the rotational conformational state of the 2B sub-domain, suggesting that 2B sub-domain rotation is coupled to the function of this nucleic acid motor enzyme.

Jia, Haifeng; Korolev, Sergey; Niedziela-Majka, Anita; Maluf, Nasib K.; Gauss, George H.; Myong, Sua; Ha, Taekjip; Waksman, Gabriel; Lohman, Timothy M. (UIUC); (St. Louis-MED); (WU-MED); (UCL)

2011-11-02T23:59:59.000Z

84

Observations of Breaking Surface Wave Statistics  

Science Conference Proceedings (OSTI)

Breaking surface waves were observed during the Surface Wave Process Program with a novel acoustical instrument that makes use of underwater ambient sound to track individual breaking events. The spatial and temporal statistics of braking waves ...

Li Ding; David M. Farmer

1994-06-01T23:59:59.000Z

85

Breaking of Wind-Generated Waves  

Science Conference Proceedings (OSTI)

Breaking of wind-generated waves was studies in a laboratory tank. The critical surface slope and global wave steepness for inception of breaking were evaluated. Besides the frequency of occurrence, two other characteristic quantities, height and ...

Delun Xu; Paul A. Hwang; Jin Wu

1986-12-01T23:59:59.000Z

86

Inhomogeneous chiral symmetry breaking phases  

Science Conference Proceedings (OSTI)

We investigate inhomogeneous chiral symmetry breaking phases in the phase diagram of the two-flavor Nambu-Jona-Lasinio model, concentrating on phases with one-dimensional modulations. It is found that the first-order transition line in the phase diagram of homogeneous phases gets completely covered by an inhomogeneous phase which is bordered by second-order transition lines. The inhomogeneous phase turns out to be remarkably stable when vector interactions are included.

Buballa, M., E-mail: michael.buballa@physik.tu-darmstadt.de; Carignano, S., E-mail: carignano@crunch.ikp.physik.tu-darmstadt.de [Technische Universitaet Darmstadt, Institut fuer Kernphysik (Germany); Nickel, D., E-mail: mdjn@u.washington.edu [University of Washington, Institute for Nuclear Theory (United States)

2012-06-15T23:59:59.000Z

87

Chaotic inflation and supersymmetry breaking  

E-Print Network (OSTI)

We investigate the recently proposed class of chaotic inflation models in supergravity with an arbitrary inflaton potential. These models are extended to include matter fields in the visible sector and we employ a mechanism of SUSY breaking based on a particular phenomenological version of the KKLT mechanism (the KL model). We describe specific features of reheating in this class of models and show how one can solve the cosmological moduli and gravitino problems in this context.

Kallosh, Renata; Olive, Keith A; Rube, Tomas

2011-01-01T23:59:59.000Z

88

Chaotic inflation and supersymmetry breaking  

E-Print Network (OSTI)

We investigate the recently proposed class of chaotic inflation models in supergravity with an arbitrary inflaton potential. These models are extended to include matter fields in the visible sector and we employ a mechanism of SUSY breaking based on a particular phenomenological version of the KKLT mechanism (the KL model). We describe specific features of reheating in this class of models and show how one can solve the cosmological moduli and gravitino problems in this context.

Renata Kallosh; Andrei Linde; Keith A. Olive; Tomas Rube

2011-06-29T23:59:59.000Z

89

DNA hybridization kinetics: zippering, internal displacement and sequence dependence  

E-Print Network (OSTI)

While the thermodynamics of DNA hybridization is well understood, much less is known about the kinetics of this classic system. Filling this gap in our understanding has new urgency because DNA nanotechnology often depends critically on binding rates. Here we use a coarse-grained model to explore the hybridization kinetics of DNA oligomers, finding that strand association proceeds through a complex set of intermediate states. Successful binding events start with the formation of a few metastable base-pairing interactions, followed by zippering of the remaining bonds. However, despite reasonably strong interstrand interactions, initial contacts frequently fail to lead to zippering because the typical configurations in which they form differ from typical states of similar enthalpy in the double-stranded equilibrium ensemble. Therefore, if the association process is analyzed on the base-pair (secondary structure) level, it shows non-Markovian behavior. Initial contacts must be stabilized by two or three base pairs before full zippering is likely, resulting in negative effective activation enthalpies. Non-Arrhenius behavior is observed as the number of base pairs in the effective transition state increases with temperature. In addition, we find that alternative pathways involving misbonds can increase association rates. For repetitive sequences, misaligned duplexes frequently rearrange to form fully paired duplexes by two distinct processes which we label `pseudoknot' and `inchworm' internal displacement. We show how the above processes can explain why experimentally observed association rates of GC-rich oligomers are higher than rates of AT-rich equivalents. More generally, we argue that association rates can be modulated by sequence choice.

Thomas E. Ouldridge; Petr Šulc; Flavio Romano; Jonathan P. K. Doye; Ard A. Louis

2013-03-14T23:59:59.000Z

90

Introduction to Electroweak Symmetry Breaking  

SciTech Connect

The Standard Model (SM) is the backbone of elementary particle physics-not only does it provide a consistent framework for studying the interactions of quark and leptons, but it also gives predictions which have been extensively tested experimentally. In these notes, I review the electroweak sector of the Standard Model, discuss the calculation of electroweak radiative corrections to observables, and summarize the status of SM Higgs boson searches. Despite the impressive experimental successes, however, the electroweak theory is not completely satisfactory and the mechanism of electroweak symmetry breaking is untested. I will discuss the logic behind the oft-repeated statement: 'There must be new physics at the TeV scale'. These lectures reflect my strongly held belief that upcoming results from the LHC will fundamentally change our understanding of electroweak symmetry breaking. In these lectures, I review the status of the electroweak sector of the Standard Model, with an emphasis on the importance of radiative corrections and searches for the Standard Model Higgs boson. A discussion of the special role of the TeV energy scale in electroweak physics is included.

Dawson,S.

2008-10-02T23:59:59.000Z

91

QCD, Symmetry Breaking and the Random Lattice  

E-Print Network (OSTI)

According to the Nielsen-Ninomiya No-Go theorem, the doubling of fermions on the lattice cannot be suppressed in a chiral theory. Whereas Wilson and staggered fermions suppress doublers with explicit breaking of chiral symmetry, the random lattice does so by spontaneous chiral symmetry breaking even in the free theory. I present results for meson masses, the chiral condensate and fermionic eigenvalues from simulations of quenched QCD on random lattices in four dimensions, focusing on chiral symmetry breaking. 1.

Saul D. Cohen A

2006-01-01T23:59:59.000Z

92

System Break-Out Session  

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

Alkaline Membrane Fuel Cell Alkaline Membrane Fuel Cell Workshop System Break-Out Session Anil Trehan (CommScope) Huyen Dinh (NREL) 5/8 - 5/9/11 Washington DC Current State-of-art Performance * MEA level - 200 mW/cm2 peak power at 0.5 V, 60-65C * System level - Air-cooled 2 kW (net) - Energy density is advantage over incumbent battery and Gensets for stationary application - Significant price advantage over PEM fuel cells * Refer to CellEra and Tokuyama presentations for more details Application - Alcohol fuel small power levels Application Description Power range Military Remote sensor < 10 W Soldier Power 20- 50 W Battery charger 300 W Commercial Consumer electronics < 100 W Recreation < 500 W Commercial Application - Hydrogen Description Power range Back-up 1 - 10 kW Material Handling 1 - 10 kW Transportation

93

Degeneracy Breaking of Hydrogen Atom  

E-Print Network (OSTI)

The three dimensional rotation group, SO(3), is a symmetry group of the normal hydrogen atom. Each reducible representation of this group can be associated with a degenerate energy level. If this atom is placed in an external magnetic field, the interaction between the orbital magnetic moment with this field will lead to a symmetry breaking where the symmetry group of the atom is a new group distinct from the SO(3) group. This phenomenon describes the normal Zeeman effect, where a degenerate energy level splits into several new energy levels. It is explicitly shown that each of the new energy levels can be associated with an irreducible representation of the new symmetry group.

Agung Trisetyarso; Pantur Silaban

2008-12-22T23:59:59.000Z

94

Microsoft PowerPoint - Powerpoint_WebRepair.ppt [Compatibility...  

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

strand break repair is usually error free. g p y * Double strand breaks can be either error free or error t i i hi h t prone, containing a high error rate. Mechanisms of Repair...

95

Vanadium catalysts break down biomass for fuels  

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

Vanadium catalysts break down biomass for fuels Vanadium catalysts break down biomass for fuels Vanadium catalysts break down biomass into useful components Breaking down biomass could help in converting biomass to fuels. March 26, 2012 Biomass Due to diminishing petroleum reserves, non-food biomass (lignocellulose) is an attractive alternative as a feedstock for the production of renewable chemicals and fuels. Get Expertise Researcher Susan Hanson Inorganic Isotope & Actinide Chem Email Researcher Ruilian Wu Bioenergy & Environmental Science Email Researcher Louis "Pete" Silks Bioenergy & Environmental Science Email Vanadium is an inexpensive, earth-abundant metal that is well suited for promoting oxidations in air. Vanadium catalysts break down biomass into useful components Due to diminishing petroleum reserves, non-food biomass (lignocellulose) is

96

A Newly Discovered DNA Repair Mechanism | Advanced Photon Source  

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

scanning for these lesions. When they encounter one, they break the base pair bond and flip the deformed base out of the DNA double helix. The enzyme contains a specially shaped...

97

Dirac Neutrino Masses from Generalized Supersymmetry Breaking  

SciTech Connect

We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the standard model with a generalized supersymmetry breaking sector. If the superpotential neutrino Yukawa terms are forbidden by the gauge symmetry [such as a U(1){sup '}], sub-eV scale effective Dirac mass terms can arise at tree level from hard supersymmetry breaking Yukawa couplings, or at one loop due to nonanalytic soft supersymmetry breaking trilinear scalar couplings. The radiative neutrino magnetic and electric dipole moments vanish at one-loop order.

Demir, Durmus A.; Everett, Lisa L.; Langacker, Paul [Department of Physics, Izmir Institute of Technology, IZTECH, TR35430 Izmir (Turkey); Deutsches Elektronen-Synchrotron, DESY, D-22603 Hamburg (Germany); Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); School of Natural Sciences, Institute for Advanced Study, Einstein Drive, Princeton, New Jersey 08540 (United States)

2008-03-07T23:59:59.000Z

98

Spontaneous chiral parity breaking by hydromagnetic buoyancy  

E-Print Network (OSTI)

Evidence for a parity-breaking nature of the magnetic buoyancy instability in a stably stratified gas is reported. In the absence of rotation, no helicity is produced, but the non-helical state is found to be unstable to small helical perturbations during the development of the instability. The parity-breaking nature of an instability in magnetohydrodynamics appears to be the first of its kind and is similar to chiral symmetry breaking in biochemistry. Applications to the production of mean fields in galaxy clusters are being discussed.

Chatterjee, Piyali; Brandenburg, Axel; Rheinhardt, Matthias

2010-01-01T23:59:59.000Z

99

Two Types of Wave Breaking in an Aquaplanet GCM  

Science Conference Proceedings (OSTI)

The characteristics of two distinct types of wave breaking in an aquaplanet general circulation model (GCM) are described. A systematic analysis of wave breaking is possible because when a baroclinic wave packet is present, the wave breaking ...

Sukyoung Lee; Steven Feldstein

1996-03-01T23:59:59.000Z

100

Appropriately handled prosodic breaks help PCFG parsing  

Science Conference Proceedings (OSTI)

This paper investigates using prosodic information in the form of ToBI break indexes for parsing spontaneous speech. We revisit two previously studied approaches, one that hurt parsing performance and one that achieved minor improvements, and propose ...

Zhongqiang Huang; Mary Harper

2010-06-01T23:59:59.000Z

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


101

Wave Breaking Dissipation Observed with “SWIFT” Drifters  

Science Conference Proceedings (OSTI)

Energy dissipation rates during ocean wave breaking are estimated from high-resolution profiles of turbulent velocities collected within 1 m of the surface. The velocity profiles are obtained from a pulse-coherent acoustic Doppler sonar on a wave-...

Jim Thomson

2012-12-01T23:59:59.000Z

102

Modulated Tool-Path (MTP) Chip Breaking System  

Relationship between chip length, oscillation rate, and R Af . Modulated Tool-Path (MTP) Chip Breaking System 16 Fig. 11. MTP chip breaking surface fi nish model.

103

Deputy Secretary Poneman Attends Ground Breaking at Tennessee...  

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

Home Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced Vehicle Battery Plant Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced Vehicle...

104

The Effect of Wave Breaking on the Wave Energy Spectrum  

Science Conference Proceedings (OSTI)

The effect of wave breaking on the wave energy spectral shape is examined. The Stokes wave-breaking criterion is first extended to random waves and a breaking wave model is established in which the elevation of breaking waves is expressed in ...

C. C. Tung; N. E. Huang

1987-08-01T23:59:59.000Z

105

Breaking Down Stovepipes | Department of Energy  

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

Breaking Down Stovepipes Breaking Down Stovepipes Breaking Down Stovepipes Coordination with other DOE-wide teams and groups An assigned liaison to DOE's NEPA [National Environmental Policy Act] Six Sigma Team Coordination with the Facilities and Infrastructure Steering Committee: Ten-Year Site Plan requirements, streamlining processes for transferring facilities, work for others Communication across sites, programs, and communities to share lessons learned Kansas City Office coordinating with Oak Ridge and the Office of Environmental Management on the Bannister Federal Complex disposal lessons learned Office of Science sharing lessons on private industry opportunities to expand research capabilities at Oak Ridge and Brookhaven National Lab and on the use of opportunities offered by local government

106

Symmetry Breaking in Linearly Coupled Dynamical Lattices  

E-Print Network (OSTI)

We examine one- and two-dimensional (1D and 2D) models of linearly coupled lattices of the discrete-nonlinear-Schr{\\"{o}}dinger type. Analyzing ground states of the systems with equal powers in the two components, we find a symmetry-breaking phenomenon beyond a critical value of the squared $l^2$-norm. Asymmetric states, with unequal powers in their components, emerge through a subcritical pitchfork bifurcation, which, for very weakly coupled lattices, changes into a supercritical one. We identify the stability of various solution branches. Dynamical manifestations of the symmetry breaking are studied by simulating the evolution of the unstable branches. The results present the first example of spontaneous symmetry breaking in 2D lattice solitons. This feature has no counterpart in the continuum limit, because of the collapse instability in the latter case.

Herring, G; Malomed, B A; Carretero-González, R; Frantzeskakis, D J

2007-01-01T23:59:59.000Z

107

DNA Record  

Science Conference Proceedings (OSTI)

... 4. Field 18.004: Source agency/SRC 5. Field 18.005: DNA Record Header Information (DRI) ... Field 18.005: DNA Record Header Information (DRI) ...

2010-08-03T23:59:59.000Z

108

A gravity term from spontaneous symmetry breaking  

E-Print Network (OSTI)

In this model, the gravity term in the Lagrangean comes from spontaneous symmetry breaking of an additional scalar quadruplet field $\\Upsilon$. The resulting gravitational field is approximate to one of the models of coframe gravity with parameters $\\rho_1 + 4 \\rho_2 = 0$, $\\rho_3 = 0$. This article includes an exact solution of coframe gravity with model parameters $\\rho_1 \

Mihai Moise

2014-01-02T23:59:59.000Z

109

Facts and Myths of Enigma: breaking stereotypes  

Science Conference Proceedings (OSTI)

In spite of a relatively large number of publications about breaking Enigma by the Allies before and during the World War II, this subject remains relatively unknown not only to the general public, but also to people professionally involved in cryptological ... Keywords: Enigma, cipher machine, codebreaking, cryptanalytical bombe, rotor

Kris Gaj; Arkadiusz Or?owski

2003-05-01T23:59:59.000Z

110

Function of the ATR N-terminal domain revealed by an ATM/ATR chimera  

SciTech Connect

The ATM and ATR kinases function at the apex of checkpoint signaling pathways. These kinases share significant sequence similarity, phosphorylate many of the same substrates, and have overlapping roles in initiating cell cycle checkpoints. However, they sense DNA damage through distinct mechanisms. ATR primarily senses single stranded DNA (ssDNA) through its interaction with ATRIP, and ATM senses double strand breaks through its interaction with Nbs1. We determined that the N-terminus of ATR contains a domain that binds ATRIP. Attaching this domain to ATM allowed the fusion protein (ATM*) to bind ATRIP and associate with RPA-coated ssDNA. ATM* also gained the ability to localize efficiently to stalled replication forks as well as double strand breaks. Despite having normal kinase activity when tested in vitro and being phosphorylated on S1981 in vivo, ATM* is defective in checkpoint signaling and does not complement cellular deficiencies in either ATM or ATR. These data indicate that the N-terminus of ATR is sufficient to bind ATRIP and to promote localization to sites of replication stress.

Chen Xinping [Department of Biochemistry, Vanderbilt University, 613 Light Hall, 23rd, Pierce Avenue, Nashville, TN 37232 (United States); Zhao Runxiang [Department of Biochemistry, Vanderbilt University, 613 Light Hall, 23rd, Pierce Avenue, Nashville, TN 37232 (United States); Glick, Gloria G. [Department of Biochemistry, Vanderbilt University, 613 Light Hall, 23rd, Pierce Avenue, Nashville, TN 37232 (United States); Cortez, David [Department of Biochemistry, Vanderbilt University, 613 Light Hall, 23rd, Pierce Avenue, Nashville, TN 37232 (United States)]. E-mail: david.cortez@vanderbilt.edu

2007-05-01T23:59:59.000Z

111

DNA Extraction  

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

DNA Extraction DNA Extraction Being able to extract deoxyribonucleic acid (DNA) is important for a number of reasons. By studying DNA, scientists can identify genetic disorders or diseases, and they can also possibly find cures for them by manipulating or experimenting with this DNA. At the Laboratory, researchers have studied DNA to detect biothreat agents in environmental and forensic samples. Scientists also are studying how human DNA may be destroyed by certain types of electromagnetic waves at certain frequencies. Classroom Activity: This activity is about the extraction of DNA from strawberries. Strawberries are a great fruit to use for this lesson because each student can work on his or her own. Strawberries are recommended because they yield more DNA than any other fruit. Strawberries are octoploid, which means that they have eight copies of each

112

Simulation of Wave Breaking in One-Dimensional Spectral Environment  

Science Conference Proceedings (OSTI)

Results of numerical investigations, based on full dynamic equations, are presented for wave breaking in a one-dimensional environment with a wave spectrum. The breaking is defined as a process of irreversible collapse of an individual wave in ...

Dmitry Chalikov; Alexander V. Babanin

2012-11-01T23:59:59.000Z

113

Wave–Turbulence Interactions in a Breaking Mountain Wave  

Science Conference Proceedings (OSTI)

The mean and turbulent structures in a breaking mountain wave are considered through an ensemble of high-resolution (essentially large-eddy simulation) wave-breaking calculations. Of particular interest are the turbulent heat and momentum fluxes ...

Craig C. Epifanio; Tingting Qian

2008-10-01T23:59:59.000Z

114

Wave Breaking and Ocean Surface Layer Thermal Response  

Science Conference Proceedings (OSTI)

The effect of breaking waves on ocean surface temperatures and surface boundary layer deepening is investigated. The modification of the Mellor–Yamada turbulence closure model by Craig and Banner and others to include surface wave breaking ...

George Mellor; Alan Blumberg

2004-03-01T23:59:59.000Z

115

Spectral Energy Dissipation due to Surface Wave Breaking  

Science Conference Proceedings (OSTI)

A semiempirical determination of the spectral dependence of the energy dissipation due to surface wave breaking is presented and then used to propose a model for the spectral dependence of the breaking strength parameter b, defined in the O. M. ...

Leonel Romero; W. Kendall Melville; Jessica M. Kleiss

2012-09-01T23:59:59.000Z

116

Breaking Probability for Dominant Waves on the Sea Surface  

Science Conference Proceedings (OSTI)

The breaking probability is investigated for the dominant surface waves observed in three geographically diverse natural bodies of water: Lake Washington, the Black Sea, and the Southern Ocean. The breaking probability is taken as the average ...

Michael L. Banner; Alexander V. Babanin; Ian R. Young

2000-12-01T23:59:59.000Z

117

Breaking the Fuel Cell Cost Barrier  

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

Breaking the Fuel Cell Cost Barrier Breaking the Fuel Cell Cost Barrier AMFC Workshop May 8 th , 2011, Arlington, VA Shimshon Gottesfeld, CTO The Fuel Cell Cost Challenge 2 CellEra's goal - achieve price parity with incumbents earlier on in market entry process ! Mainstream Polymer Electrolyte Fuel Cell ( PEM) Cost Barriers 3 Graphite / stainless steel hardware Acidic membrane Platinum based electrodes Cost barriers deeply embedded in core tech materials BOM-based cost barriers - 90% of stack cost Cost volatility - Platinum $500/Oz - $2,500/Oz The possibility of an OH - ion conducting membrane 4 Non-acidic membrane CellEra Took Advantage of this Opportunity A new type of membrane component with potential for strong fuel cell cost cuts was revealed in 2006, but was accompanied by general industry skepticism

118

Breaking the Code of Cell Communication  

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

Breaking the Code of Cell Communication Breaking the Code of Cell Communication A method that cells use to communicate and coordinate activities has been confirmed by researchers from Cornell University, Monsanto Co., and Argonne. This work could lead to new drugs for the fight against such diseases as cystic fibrosis and the bubonic plague, or to new technologies that perform useful environmental tasks such as filtering water. The structure of the key protein that enables quorum-sensing bacteria to communicate and spread infection. Above: The structure of the key protein that enables quorum-sensing bacteria to communicate and spread infection. Biologists have theorized that bacteria communicate by releasing and sensing chemical pheromones to detect their population densities, an activity called "quorum sensing." This theory was confirmed by

119

Textural break foundation wall construction modules  

SciTech Connect

Below-grade, textural-break foundation wall structures are provided for inhibiting diffusion and advection of liquids and gases into and out from a surrounding hydrogeologic environment. The foundation wall structure includes a foundation wall having an interior and exterior surface and a porous medium disposed around a portion of the exterior surface. The structure further includes a modular barrier disposed around a portion of the porous medium. The modular barrier is substantially removable from the hydrogeologic environment.

Phillips, Steven J. (Kennewick, WA)

1990-01-01T23:59:59.000Z

120

Depolarization remote sensing by orthogonality breaking  

E-Print Network (OSTI)

A new concept devoted to sensing the depolarization strength of materials from a single measurement is proposed and successfully validated on a variety of samples. It relies on the measurement of the orthogonality breaking between two orthogonal states of polarization after interaction with the material to be characterized. The two fields orthogonality being preserved after propagation in birefringent media, this concept is shown to be perfectly suited to depolarization remote sensing through fibers, opening the way to real time depolarization endoscopy.

Fade, Julien

2012-01-01T23:59:59.000Z

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


121

DNA Biometrics  

Science Conference Proceedings (OSTI)

... presentation at Advances in Forensic DNA Analysis workshop held at the American Academy of Forensic Sciences meeting (Seattle, WA), February ...

2013-03-15T23:59:59.000Z

122

Forensic DNA:  

Science Conference Proceedings (OSTI)

... January 17, 2008 Press Release From Mayor Bloomberg's STATE OF THE CITY ADDRESS Efforts towards Portable/Mobile DNA Devices ...

2008-09-29T23:59:59.000Z

123

Low Dose Radiation Research Program: Research Highlights - 2010  

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

DNA Double-Strand Break Repair Capacities Before and After Exposure to Low DNA Double-Strand Break Repair Capacities Before and After Exposure to Low Dose Radiation Immunochemical detection of DSB foci in the nuclei of human fibroblasts. (A) γ-H2AX phospho-serine 139 foci (chromatin marker of DSBs; green). (B) ataxia-telangiectasia mutated phospho-serine 1981 foci (ATM, DNA damage-responsive kinase; red). (C) Merge of images A and B. (White arrows mark large γ-H2AX foci and coincident γ-H2AX/pATM foci that were positively scored; yellow arrows mark small γ-H2AX foci that lack corresponding pATM foci that were not scored.) Enlarge Image Immunochemical detection of DSB foci in the nuclei of human fibroblasts. (A) γ-H2AX phospho-serine 139 foci (chromatin marker of DSBs; green). (B) ataxia-telangiectasia mutated phospho-serine 1981 foci (ATM,

124

Breaking Criterion and Characteristics for Solitary Waves on Slopes  

E-Print Network (OSTI)

Shoaling and breaking of solitary waves is computed on slopes 1:100 to 1:8 using an experimentally validated fully nonlinear wave model based on potential flow equations. Characteristics of waves are computed at and beyond the breaking point, and geometric self-similarities of breakers are discussed as a function of wave height and bottom slope. No wave breaks for slopes steeper than 12 . A breaking criterion is derived for milder slopes, based on values of a nondimensional slope parameter o . This criterion predicts both whether waves will break or not and which type of breaking will occur (spilling, plunging, or surging). Empirical expressions for the breaking index and for the depth and celerity at breaking are derived based on computations. All results agree well with laboratory experiments. The NSW equations fail to predict these results with sufficient accuracy at the breaking point. Pre-breaking shoaling rates follow a more complex path than previously realized. Post-breaking behaviors exhibit a rapid (non-dissipative) decay, also observed in experiments, associated with a transfer of potential energy into kinetic energy. Wave celerity decreases in this zone of rapid decay.

S. T. Grilli; I.A. Svendsen; Member Asce; Member Asce; R. Subramanya

1997-01-01T23:59:59.000Z

125

SUSY breaking from exotic U(1)  

SciTech Connect

We propose a mechanism that the soft supersymmetry breaking masses can be induced from the dynamical rearrangement of local U(1) symmetry in a five-dimensional model. The U(1) symmetry possesses several extraordinary features. The eigenstates of U(1) do not equal to those of boundary conditions. The U(1) charge of standard model particles does not equal to that of superpartners. A large U(1) charge hierarchy among superpartners and a standard model gauge singlet is necessary in order to obtain the masses of O(1)TeV.

Kawamura, Yoshiharu [Department of Physics, Shinshu University, Matsumoto 390-8621 (Japan)

2012-07-27T23:59:59.000Z

126

Patterns of Spontaneous Chiral Symmetry Breaking in Vectorlike Gauge Theories  

E-Print Network (OSTI)

It has been conjectured that spontaneous chiral symmetry breaking in strongly coupled vectorlike gauge theories falls into only three different classes, depending on the gauge group and the representations carried by the fermions. We test this proposal by studying SU(2), SU(3) and SU(4) lattice gauge theories with staggered fermions in different irreducible representations. Staggered fermions away from the continuum limit should, for all complex representations, still belong to the continuum class of spontaneous symmetry breaking. But for all real and pseudo-real representations we show that staggered fermions should belong to incorrect symmetry breaking classes away from the continuum, thus generalizing previous results. As an unambiguous signal for whether chiral symmetry breaks, and which breaking pattern it follows, we look at the smallest Dirac eigenvalue distributions. We find that the patterns of symmetry breaking are precisely those conjectured.

P. H. Damgaard; U. M. Heller; R. Niclasen; B. Svetitsky

2008-01-01T23:59:59.000Z

127

FEM analysis of in-flight ice break-up  

Science Conference Proceedings (OSTI)

Using a fracture mechanics framework, this paper presents a finite element method to simulate the break-up of ice accreted on the wings of aircraft. The fully automated ice break-up module is integrated in FENSAP-ICE [1,2], which is an in-flight ice ... Keywords: Finite element methods, Fracture mechanics, Ice break-up, Ice shedding, In-flight icing, Multi-physics phenomenon

Shiping Zhang; Oubai El Kerdi; Rooh A. Khurram; Wagdi G. Habashi

2012-09-01T23:59:59.000Z

128

Getting paid to break into things: Argonne's Roger Johnston on...  

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

break into "foolproof" systems. Speakers Roger Johnston Duration 4:06 Topic Security Cyber security Vulnerability assessment Video ID http:youtu.befrBBGJqkz9E Credit NBC...

129

Symmetry Breaking of H2 Dissociation by a Single Photon  

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

by breaking the molecular symmetry. A Molecular Paradox Symmetries in nature, such as the human body's bilateral symmetry and the snowflake's six-fold rotational symmetry, abound...

130

The Science of Surfing Waves and Surfing Breaks - A Review  

E-Print Network (OSTI)

affect breaking intensity. Offshore winds increase breakingbreaker intensity. Strong offshore winds make waves hard toThe perfect wind conditions for surfing are light offshore.

Scarfe, B. E.; Elwany, M. H.S.; Mead, S. T.; Black, K. P.

2003-01-01T23:59:59.000Z

131

Statistical estimation of water distribution system pipe break risk.  

E-Print Network (OSTI)

??The deterioration of pipes in urban water distribution systems is of concern to water utilities throughout the world. This deterioration generally leads to pipe breaks… (more)

Yamijala, Shridhar

2009-01-01T23:59:59.000Z

132

First Mira Runs Break New Ground with Turbulence Simulations...  

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

First Mira Runs Break New Ground with Turbulence Simulations July 16, 2013 Printer-friendly version Shortly after Mira, the ALCF's new 10-petaflops supercomputer, entered...

133

DOE Joint Genome Institute: Breaking Biomass Better, DOE JGI...  

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

12, 2010 Breaking Biomass Better: DOE JGI Sequences Wood Decaying Fungus to Advance Biofuels Prospects WALNUT CREEK, CA-One of the challenges in making cellulosic biofuels...

134

Safety Bulletin 2006-02, Natural Gas Line Breaks  

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

Natural Gas Line Breaks PURPOSE This Bulletin provides information on a safety concern that may impact operations at Department of Energy (DOE) facilities. Specifically, the...

135

A MASTER FORMULA FOR CHIRAL SYMMETRY BREAKING  

E-Print Network (OSTI)

We derive a master formula for chiral $SU(2)\\times SU(2)$ breaking, based on the Veltman-Bell equations and the Peierls-Dyson relation. Our approach does not rely on the use of the soft pion limit or an expansion around the chiral limit, and yields exact results for on-shell pions. Threshold theorems for $\\pi N\\rightarrow \\pi N$, $\\gamma N\\rightarrow \\pi N$, $\\pi N\\rightarrow\\pi\\pi N$, $\\gamma N\\rightarrow \\gamma\\pi N$, $\\gamma N\\rightarrow \\pi\\pi N$ and $\\pi N\\rightarrow \\pi\\gamma N$ are recovered, and corrections to them are given. The reactions $\\pi\\rightarrow e\

HIDENAGA YAMAGISHI; ISMAIL ZAHED

1995-03-22T23:59:59.000Z

136

Holst action and Dynamical Electroweak symmetry breaking  

E-Print Network (OSTI)

We consider Poincare gravity coupled in a nonminimal way to spinors. The gravitational action is considered that contains both Palatini and Holst terms. Due to torsion the effective four - fermion interactions appear that may lead to the left - right asymmetry and the condensation of fermions. When the mass parameter entering the mentioned terms of the gravitational action is at a Tev scale the given construction may provide the dynamical Electroweak symmetry breaking. This is achieved via an arrangement of all Standard Model fermions in the left - handed Dirac spinors while the right - handed spinors are reserved for the technifermions. Due to the gravitational action the technifermions are condensed and, therefore, cause the appearance of gauge boson masses.

M. A. Zubkov

2010-04-08T23:59:59.000Z

137

Dynamical Local Chirality and Chiral Symmetry Breaking  

E-Print Network (OSTI)

We present some of the reasoning and results substantiating the notion that spontaneous chiral symmetry breaking (SChSB) in QCD is encoded in local chiral properties of Dirac eigenmodes. Such association is possible when viewing chirality as a dynamical effect, measured with respect to the benchmark of statistically independent left-right components. Following this rationale leads to describing local chiral behavior by a taylor-made correlation, namely the recently introduced correlation coefficient of polarization C_A. In this language, correlated modes (C_A>0) show dynamical preference for local chirality while anti-correlated modes (C_Aenergy correlation (chirality) over anti-correlation (anti-chirality) of Dirac sea. The spectral range of local chirality, chiral polarization scale Lambda_ch, is a dynamically generated scale in the theory associated with SChSB. One implication of these findings is briefly dis...

Alexandru, Andrei

2013-01-01T23:59:59.000Z

138

Modified Gravity via Spontaneous Symmetry Breaking  

E-Print Network (OSTI)

We construct effective field theories in which gravity is modified via spontaneous breaking of local Lorentz invariance. This is a gravitational analogue of the Higgs mechanism. These theories possess additional graviton modes and modified dispersion relations. They are manifestly well-behaved in the UV and free of discontinuities of the van Dam-Veltman-Zakharov type, ensuring compatibility with standard tests of gravity. They may have important phenomenological effects on large distance scales, offering an alternative to dark energy. For the case in which the symmetry is broken by a vector field with the wrong sign mass term, we identify four massless graviton modes (all with positive-definite norm for a suitable choice of a parameter) and show the absence of the discontinuity.

B. M. Gripaios

2004-08-17T23:59:59.000Z

139

Transcriptional and Epigenetic Responses of Human Cells to Low Dose  

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

Transcriptional and Epigenetic Responses of Human Cells to Low Dose Transcriptional and Epigenetic Responses of Human Cells to Low Dose Ionizing Radiation Identified through High Throughput ChIP-Seq Analysis Carl Anderson Brookhaven National Laboratory Abstract The major consequence of human exposures to ionizing radiation (IR) is considered to be an increased incidence of cancer (Brenner et al., 2003). Exposure of cells to 1 Gy of IR produces approximately 40 double-stranded breaks, 1000 single-stranded breaks, and 1000 damaged bases per genome equivalent (Pandita and Richardson, 2009); however, most direct DNA damage is rapidly repaired. Exposure to IR also induces epigenetic changes including both increases and decreases in DNA methylation, and increasing evidence suggests that epigenetic changes can both initiate cancer and

140

Gas exploration beyond the shelf break: An oceanographic challenge  

Science Conference Proceedings (OSTI)

Norway's second largest gas field, Ormen Lange, is located 140km west off Kristiansund at an unprecedented depth when it comes to exploration. It will be the first Norwegian project beyond the shelf break. Exploration and development of the field is ... Keywords: Currents, Offshore oil industry, Shelf break, Shelf slope, Waves

Ø. Thiem; J. Berntsen; T. Eldevik; G. Alendal

2006-02-01T23:59:59.000Z

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


141

Programmable repression and activation of bacterial gene expression using an engineered CRISPR-Cas system  

E-Print Network (OSTI)

The ability to artificially control transcription is essential both to the study of gene function and to the construction of synthetic gene networks with desired properties. Cas9 is an RNA-guided double-stranded DNA nuclease ...

Zhang, Feng

142

Genes and structural proteins of the phage SYN5 of the marine cyanobacteria, Synechococcus  

E-Print Network (OSTI)

Bacteriophage have been proposed to be the most abundant organisms on the planet, at an estimated 10³¹ particles globally (Hendrix et al., 1999). The majority of bacteriophage isolates (96%) are double-stranded DNA tailed ...

Pope, Welkin Hazel

2005-01-01T23:59:59.000Z

143

Development and characterization of an in vitro culture system as a physiological model for chronic Hepatitis B infection  

E-Print Network (OSTI)

Human Hepatitis B virus (HBV) is the prototype member of the family Hepadnaviridae that consists of enveloped, partially double stranded DNA viruses that specifically target hepatocytes for viral replication. Although a ...

Sams, Alexandria V. (Alexandria Victoria)

2007-01-01T23:59:59.000Z

144

DNA Activity  

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

DNA Activity DNA Activity Name: Sara Location: N/A Country: N/A Date: N/A Question: Is DNA an anion or a cation? I thought since it was negatively charged it was an anion but mt teacher in class today said it was a cation because negatively charged molecules logically migrate to the positively charged plate of the cathode, ie molecules that migrate towards a cathode are cations. Where is the error in my logic or there error in my logic? Replies: DNA is negatively charged due to the phosphate ions present in the ribose-phosphate backbone. It moves towards the positive pole during electrophoresis. The definition kation/anion is confusing because: 1. a cation moves to the cathode 2. the cathode is negative, thus 3. a cation is positive DNA is an anion. The confusion is that a cathode is negative, but a cation is positively charged. For that reason these terms are not generally used in this context.

145

Breaking Ground in Miami-Dade | Department of Energy  

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

Breaking Ground in Miami-Dade Breaking Ground in Miami-Dade Breaking Ground in Miami-Dade October 15, 2010 - 4:28pm Addthis Existing Miami-Dade county water treatment facility. Existing Miami-Dade county water treatment facility. Andy Oare Andy Oare Former New Media Strategist, Office of Public Affairs Officials from Miami-Dade County and the U.S. Department of Energy were on hand Wednesday, October 13th to formally break ground on an innovative project that will help improve the energy efficiency of one of the county's major water treatment facilities. The project will upgrade and expand the existing power generation system at the water plant which generates electricity from digester gas produced at the plant. Landfill gas, which is produced from the Solid Waste Department's South Dade Landfill, will be collected and piped across a

146

Pantex breaks ground on renewable energy project | National Nuclear  

National Nuclear Security Administration (NNSA)

breaks ground on renewable energy project | National Nuclear breaks ground on renewable energy project | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > NNSA Blog > Pantex breaks ground on renewable energy project Pantex breaks ground on renewable energy project Posted By Office of Public Affairs Today was a rare windless day on the plains of the Texas Panhandle, but

147

Symmetry Breaking of H2 Dissociation by a Single Photon  

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

Symmetry Breaking of H2 Symmetry Breaking of H2 Dissociation by a Single Photon Symmetry Breaking of H2 Dissociation by a Single Photon Print Wednesday, 25 July 2007 00:00 A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of researchers from Germany, Spain, and the U.S. has now shown that this need not be the case. When there are multiple quantum paths for the process, interference between waves in the coherent superposition of electron states (which exists when the molecular fragments are still close together) skews the distribution by breaking the molecular symmetry.

148

Pantex breaks ground on renewable energy project | National Nuclear  

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

breaks ground on renewable energy project | National Nuclear breaks ground on renewable energy project | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > NNSA Blog > Pantex breaks ground on renewable energy project Pantex breaks ground on renewable energy project Posted By Office of Public Affairs Today was a rare windless day on the plains of the Texas Panhandle, but

149

Energy Dissipation of Unsteady Wave Breaking on Currents  

Science Conference Proceedings (OSTI)

Energy dissipation for unsteady deep-water breaking in wave groups on following and opposing currents, including partial wave-blocking conditions, was investigated by detailed laboratory measurements. A range of focusing wave conditions, ...

Aifeng Yao; Chin H. Wu

2004-10-01T23:59:59.000Z

150

Microsoft Word - They Bend Before They Break.doc  

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

of molecules known as aryl halides was studied, in which a halogen atom, such as chlorine or bromine, dissociates from a sizable planar ring structure, breaking its bond. The...

151

Vermont Yankee simulator qualification: large-break LOCA  

Science Conference Proceedings (OSTI)

Yankee Atomic Electric Company (YAEC) has developed simulator benchmark capabilities for the Seabrook, Maine Yankee, and Vermont Yankee Nuclear Power Station (VYNPS) simulators. The goal is to establish that each simulator has a satisfactory real-time response for different scenarios that will enhance operator training. Vermont Yankee purchased a full-scope plane simulator for the VYNPS, a four-unit boiling water reactor with a Mark-I containment. The following seven benchmark cases were selected by YAEC and VYNPC to supplement the Simulator Acceptance Test Program: (1) control rod swap; (2) partial reactor scram; (3) recirculation pump trip; (4) main steam isolation valve (MSIV) closure without scram, (5) main steamline break, (6) small-break loss-of-coolant accident (LOCA), and (7) large-break LOCA. Five simulator benchmark sessions have been completed. Each session identified simulator capabilities and limitations that needed correction. This paper discusses results from the latest large-break LOCA case.

Loomis, J.N.; Fernandez, R.T.

1987-01-01T23:59:59.000Z

152

Secondary Instabilities in Breaking Inertia–Gravity Waves  

Science Conference Proceedings (OSTI)

The three-dimensionalization of turbulence in the breaking of nearly vertically propagating inertia–gravity waves is investigated numerically using singular vector analysis applied to the Boussinesq equations linearized about three two-dimensional ...

Mark D. Fruman; Ulrich Achatz

2012-01-01T23:59:59.000Z

153

Observations of Wave Breaking Kinematics in Fetch-Limited Seas  

Science Conference Proceedings (OSTI)

Breaking waves play an important role in air–sea interaction, enhancing momentum flux from the atmosphere to the ocean, dissipating wave energy that is then available for turbulent mixing, injecting aerosols and sea spray into the atmosphere, and ...

Jessica M. Kleiss; W. Kendall Melville

2010-12-01T23:59:59.000Z

154

Moist Dynamics of Extended Monsoon Breaks over South Asia  

Science Conference Proceedings (OSTI)

In the present research to identify moist processes that initiate and maintain extended monsoon breaks over South Asia moisture and moist static energy (MSE) budgets are performed on the newly available European Centre for Medium-Range Weather ...

V. Prasanna; H. Annamalai

2012-06-01T23:59:59.000Z

155

Wave Breaking and Transition to Turbulence in Stratified Shear Flows  

Science Conference Proceedings (OSTI)

In a previous study the authors used a nonlinear, compressible, spectral collocation numerical model to examine the evolution of a breaking gravity wave in two and three dimensions. The present paper extends that effort to examine the ...

David C. Fritts; James F. Garten; Øyvind Andreassen

1996-04-01T23:59:59.000Z

156

Bubbles Produced by Breaking Waves in Fresh and Salt Waters  

Science Conference Proceedings (OSTI)

A greater volume of air is entrained by breaking waves to produce many more bubbles in salt, than in fresh, water. There are, however, little differences in their sizes. These results are consistent with reported observations of whitecaps over ...

Jin Wu

2000-07-01T23:59:59.000Z

157

Wave Breaking Dissipation in a Young Wind Sea  

Science Conference Proceedings (OSTI)

Coupled in situ and remote sensing measurements of young, strongly-forced, wind waves are applied to assess the role of breaking in an evolving wavefield. In situ measurements of turbulent energy dissipation from wave-following “SWIFT” drifters ...

Michael Schwendeman; Jim Thomson; Johannes R. Gemmrich

158

Holographic theories of electroweak symmetry breaking without a Higgs Boson  

E-Print Network (OSTI)

Breaking without a Higgs Boson Gustavo Burdman a and1] or theories where the Higgs boson arises as a compositeto build models of a composite Higgs boson [4] and dynamical

Burdman, Gustavo; Nomura, Yasunori

2003-01-01T23:59:59.000Z

159

Air Bubbles Produced by Breaking Wind Waves: A Laboratory Study  

Science Conference Proceedings (OSTI)

Air bubbles produced by breaking wind waves are measured in a laboratory tank to study bubble clouds produced in freshwater under various wind and wave conditions. Vertical entrainment of bubbles and their size compositions are found to be ...

Paul A. Hwang; Y-H. L. Hsu; Jin Wu

1990-01-01T23:59:59.000Z

160

Passive Acoustic Determination of Wave-Breaking Events and Their Severity across the Spectrum  

Science Conference Proceedings (OSTI)

A passive acoustic method of detecting breaking waves of different scales has been developed. The method also showed promise for measuring breaking severity.

Richard Manasseh; Alexander V. Babanin; Cameron Forbes; Kate Rickards; Irena Bobevski; Andrew Ooi

2006-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Novel effects in electroweak breaking from a hidden sector  

SciTech Connect

The Higgs boson offers a unique window to hidden sector fields S{sub i}, singlets under the standard model gauge group, via the renormalizable interactions |H|{sup 2}S{sub i}{sup 2}. We prove that such interactions can provide new patterns for electroweak breaking, including radiative breaking by dimensional transmutation consistent with CERN LEP bounds, and trigger the strong enough first-order phase transition required by electroweak baryogenesis.

Espinosa, Jose Ramon [IFT-UAM/CSIC, Cantoblanco, 28049 Madrid (Spain); Quiros, Mariano [ICREA/IFAE, UAB 08193-Bellaterra Barcelona (Spain)

2007-10-01T23:59:59.000Z

162

Novel Effects in Electroweak Breaking from a Hidden Sector  

E-Print Network (OSTI)

The Higgs boson offers a unique window to hidden sector fields S_i, singlets under the Standard Model gauge group, via the renormalizable interactions |H|^2 S_i^2. We prove that such interactions can provide new patterns for electroweak breaking, including radiative breaking by dimensional transmutation consistent with LEP bounds, and trigger the strong enough first order phase transition required by electroweak baryogenesis.

Jose Ramon Espinosa; Mariano Quiros

2007-01-18T23:59:59.000Z

163

Dark Matter Stabilization Symmetries from Spontaneous Symmetry Breaking  

E-Print Network (OSTI)

We present a class of models in which the dark matter stabilization symmetry is generated by spontaneous symmetry breaking. These models naturally correlate the dark and electroweak symmetry breaking scales. The result is a generic mechanism linking the annihilation cross section for thermally populated dark matter with the weak scale. The thermal relic abundance, sensitivity to major precision electroweak observables and additional LHC signatures are also presented.

Walker, Devin G E

2009-01-01T23:59:59.000Z

164

Dark Matter Stabilization Symmetries from Spontaneous Symmetry Breaking  

E-Print Network (OSTI)

We present a class of models in which the dark matter stabilization symmetry is generated by spontaneous symmetry breaking. These models naturally correlate the dark and electroweak symmetry breaking scales. The result is a generic mechanism linking the annihilation cross section for thermally populated dark matter with the weak scale. The thermal relic abundance, sensitivity to major precision electroweak observables and additional LHC signatures are also presented.

Devin G. E. Walker

2009-07-20T23:59:59.000Z

165

Reactivity studies of antitumor active dirhodium compounds with DNA oligonucleotides  

E-Print Network (OSTI)

The study of the mechanism of action of an antitumor active drug is essential for improving the efficacy and reducing the side effects of the drug as well as for developing better alternatives. In this vein, reactions of dirhodium compounds with DNA oligonucleotides were investigated by the techniques of mass spectrometry, HPLC, and NMR spectroscopic analytical methods. The relative reactivities of three dirhodium compounds, namely Rh2(O2CCH3)4, Rh2(O2CCF3)4, and [Rh2(O2CCH3)2(CH3CN)6](BF4)2, with DNA oligonucleotides were studied and compared to the clinically used anticancer drugs cisplatin and carboplatin using both MALDI and ESI mass spectrometric methods. The compound Rh2(O2CCF3)4 exhibits the highest reactivity among the dirhodium compounds, which is comparable to cisplatin, followed by [Rh2(O2CCH3)2(CH3CN)6](BF4)2, and finally Rh2(O2CCH3)4 which is the least reactive. Various dirhodium-oligonucleotide adducts were detected with both MALDI and ESI methods, which involve substitution of different numbers of the original ligands of the given dirhodium compound. ESI MS was found to be a sufficiently soft ionization method for detecting intact metal adducts, and CID MS-MS was useful for detecting weakly bound species such as axial adducts [M+Rh2(O2CCH3)4] and for comparing the relative bond strength between ligands in the metal adduct. A combination of anion exchange HPLC purification and enzymatic digestion studies of the adducts of Rh2(O2CCH3)4 with the 5'-CCTTCAACTCTC oligonucleotide revealed that Rh2(O2CCH3)4 binds to the center or to the ends of the oligonucleotide sequence by displacement of one or two acetate groups. Kinetic products of the type [M+Rh2(O2CCH3)3] obtained from the reaction of Rh2(O2CCH3)4 with 5'-CTCTCAACTTCC were separated by employing both reverse phase and anion exchange HPLC methods. The adduct that involves binding of the dirhodium unit to the exocyclic N4 atom of C5 and the N7 of A6 was found to be most stable whereas other adducts involving binding of C3 or C12 residues are clearly less stable. Reaction of cis-[Rh2(DAP)(O2CCH3)3(CH3OH)](O2CCH3) (DAP = 1,12- diazaperylene) with 5'-CTCTCAACTTCC produced a major adduct in which DAP group intercalates between 6A and 7A in the double stranded adduct with the rhodium atom that is not coordinated to the DAP group forming a covalent bond to the N7 atom of 6A which lends stability to the adduct.

Kang, Mijeong

2005-12-01T23:59:59.000Z

166

Localization of CHl1-related helicase genes to human chromosome regions 12p11 and 12p13: Similarity between parts of these genes and conserved human telomeric-associated DNA  

Science Conference Proceedings (OSTI)

The helicase enzymes are essential components of a number of multi-protein complexes, including those that regulate transcription, splicing, translation, and DNA repair. These enzymes assist in the unwinding of double-stranded DNA and RNA as an essential part of their function. The yeast Chl1 gene encodes a putative helicase that appears to be essential for normal chromosome transmission. Human cDNAs related to this yeast gene, hCHLR1 and hCHLR2, were recently isolated and shown to encode products that localize to the nucleus. Two corresponding genes have now been partially characterized and localized to human chromosome regions 12p11 and 12p13, indicating that this gene is contained with a duplicated region localized to 12p. In addition, a comparison of the hCHLR gene sequences with available databases indicates that a large portion of these genes, including exons encoding two functional domains of the carboxyl-terminal region of these proteins, has been duplicated as part of a larger human teleomeric repeat sequence found on many human chromosomes. Our results suggest that duplication of a relatively large region of chromosome 12p containing this putative helicase gene has resulted in the creation of numerous pseudogenes as part of a subtelomeric repeat. The presence of these helicase pseudogenes, as well as pseudogenes for other genes such as the interleukin-9 receptor, within many subtelomeric regions support the possibility that the spread of this region is subject to exchange between different chromosomes and may have implications for elucidation of the mechanism of intra- and interchromosomal duplication events. 21 refs., 4 figs.

Amann, J.; Kidd, V.J.; Lahti, J.M.; Valentine, M. [St. Jude Children`s Research Hospital, Memphis, TN (United States)

1996-03-01T23:59:59.000Z

167

NREL: News Feature - NREL Breaks Down Walls for Biofuels  

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

NREL Breaks Down Walls for Biofuels NREL Breaks Down Walls for Biofuels November 30, 2009 Researchers at the National Renewable Energy Laboratory (NREL) and ethanol producers are racing to come up with ways to make ethanol from cellulosic biomass that are cheaper and easier to produce than current methods. But they are hitting a wall. Cell walls in plants are making the production of cellulosic ethanol a challenge. So researchers are creating their own computer program to help model and break down the tiny fibers of cellulose - or fibrils - found in plant cells. Although ethanol is becoming more available to consumers, NREL is working closely with the U.S. Department of Energy (DOE) to meet a quickly approaching goal to produce competitively priced ethanol for $1.50 per gallon by 2012. Why the rush? DOE believes this is the price at which

168

SB Electronics Breaks Ground on New Factory | Department of Energy  

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

SB Electronics Breaks Ground on New Factory SB Electronics Breaks Ground on New Factory SB Electronics Breaks Ground on New Factory April 29, 2010 - 5:22pm Addthis U.S. Rep. Peter Welch (from left), Vermont Lt. Gov. Brian Dubie, SBE board member Win Hunter, SBE board chair Stan Fishkin, Assi U.S. Rep. Peter Welch (from left), Vermont Lt. Gov. Brian Dubie, SBE board member Win Hunter, SBE board chair Stan Fishkin, Assi Paul Lester Communications Specialist, Office of Energy Efficiency and Renewable Energy A Vermont company broke ground on a new factory that will produce cutting-edge technology for electric and hybrid cars and create more than 100 jobs. The event ushering in SB Electronics' power ring capacitor facility in Barre was attended by Vermont Gov. Jim Douglas and federal, state and local

169

Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced  

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

Attends Ground Breaking at Tennessee Attends Ground Breaking at Tennessee Advanced Vehicle Battery Plant Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced Vehicle Battery Plant May 26, 2010 - 12:00am Addthis Smyrna, TN - Today, U.S. Deputy Secretary of Energy Daniel Poneman participated in the groundbreaking ceremony for Nissan North America's advanced battery manufacturing facility in Smyrna, Tennessee. This past January the Department closed a $1.4 billion loan with Nissan North America to retool the Smyrna factory to build advanced electric automobiles and an advanced battery manufacturing facility. "I'm excited about the future we have begun to build here today -- a future where America's workers have good jobs, making clean cars that will reduce our dependence on oil and help us transition to a clean energy economy,"

170

Symmetry Breaking of H2 Dissociation by a Single Photon  

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

Symmetry Breaking of H2 Dissociation by a Single Photon Print Symmetry Breaking of H2 Dissociation by a Single Photon Print A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of researchers from Germany, Spain, and the U.S. has now shown that this need not be the case. When there are multiple quantum paths for the process, interference between waves in the coherent superposition of electron states (which exists when the molecular fragments are still close together) skews the distribution by breaking the molecular symmetry.

171

Symmetry Breaking of H2 Dissociation by a Single Photon  

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

Symmetry Breaking of H2 Dissociation by a Single Photon Print Symmetry Breaking of H2 Dissociation by a Single Photon Print A single hydrogen (or deuterium) molecule consists of only two protons (deuterons) and two electrons and is perfectly symmetric. Linearly polarized photons are similarly symmetric. So one might think that the angular distribution of photoelectrons resulting from photoionization of the molecule by the photon accompanied by dissociation into a hydrogen atom and a hydrogen ion would itself be symmetric. However, an international team of researchers from Germany, Spain, and the U.S. has now shown that this need not be the case. When there are multiple quantum paths for the process, interference between waves in the coherent superposition of electron states (which exists when the molecular fragments are still close together) skews the distribution by breaking the molecular symmetry.

172

Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced  

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

Poneman Attends Ground Breaking at Tennessee Poneman Attends Ground Breaking at Tennessee Advanced Vehicle Battery Plant Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced Vehicle Battery Plant May 26, 2010 - 12:00am Addthis Smyrna, TN - Today, U.S. Deputy Secretary of Energy Daniel Poneman participated in the groundbreaking ceremony for Nissan North America's advanced battery manufacturing facility in Smyrna, Tennessee. This past January the Department closed a $1.4 billion loan with Nissan North America to retool the Smyrna factory to build advanced electric automobiles and an advanced battery manufacturing facility. "I'm excited about the future we have begun to build here today -- a future where America's workers have good jobs, making clean cars that will reduce our dependence on oil and help us transition to a clean energy economy,"

173

Wind Power Reliability: Breaking Down a Barrier | Department of Energy  

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

Wind Power Reliability: Breaking Down a Barrier Wind Power Reliability: Breaking Down a Barrier Wind Power Reliability: Breaking Down a Barrier June 25, 2010 - 12:16pm Addthis EnerNex Corporation is developing documentation and validating generic wind turbine and plant models that test reliability. | File photo EnerNex Corporation is developing documentation and validating generic wind turbine and plant models that test reliability. | File photo Stephen Graff Former Writer & editor for Energy Empowers, EERE The steady increase of wind power on the grid presents new challenges for power system operators charged with making sure the grid stays up and running. "We need to ensure that we are going down a path that will lead to better reliability [with wind power]," said Bob Zavadil, an executive vice

174

Breaking a Pocket of Resistance in the Fight Against Cancer  

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

Breaking a Pocket of Resistance in Breaking a Pocket of Resistance in the Fight Against Cancer Breaking a Pocket of Resistance in the Fight Against Cancer Print Thursday, 12 December 2013 11:55 ras protein The new class of inhibitors interacts with a specific mutation (Glycine to Cysteine) associated with a number of types of lung cancer. Mutations in the protein K-RAS are a very common cause for certain types of human cancers and are generally associated with a poor response to standard therapies. RAS, an abbreviation of Rat Sarcoma, is a nucleotide binding protein that responds to chemical signals (nucleotides). When in the "on" state, RAS activates other proteins, resulting in a cascade of biochemical processes; in the "off" state, RAS remains inactive. Mutations in the RAS

175

Energy Department Training Breaks New Ground | Department of Energy  

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

Training Breaks New Ground Training Breaks New Ground Energy Department Training Breaks New Ground December 3, 2013 - 1:00pm Addthis The Federal Energy Management Program is now an authorized provider of continuing education units from the International Association for Continuing Education and Training. Watch the video above to learn more. Timothy Unruh FEMP Program Manager High quality education for federal government employees helps streamline operations, improve services, and ensure that taxpayer dollars are spent wisely. This is why I am pleased to announce the Energy Department's Federal Energy Management Program (FEMP) has earned the designation as an "Authorized Provider" of continuing education units (CEUs) by the prestigious International Association for Continuing Education and Training

176

Ground Breaking of Blythe Solar Power Project | Department of Energy  

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

Ground Breaking of Blythe Solar Power Project Ground Breaking of Blythe Solar Power Project Ground Breaking of Blythe Solar Power Project June 20, 2011 - 2:16pm Addthis Secretary Chu Secretary Chu Former Secretary of Energy What will the project do? Blythe Solar Power Project will generate 1,000 megawatts of solar power, enough to power more than 300,000 single-family homes a year. Back in April, I had the pleasure of announcing that the Department of Energy had extended our largest conditional loan guarantee for a solar project - $2.1 billion to support a concentrating solar thermal power plant near Blythe, California. Last Friday, the Blythe Solar Power Project broke ground, beginning construction of a project that upon completion will generate 1,000 megawatts of solar power, enough to power more than 300,000

177

Reddit AMA: Marius Stan, energy researcher and Breaking Bad actor |  

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

Reddit AMA: Marius Stan, energy researcher and Breaking Bad actor Reddit AMA: Marius Stan, energy researcher and Breaking Bad actor Reddit AMA: Marius Stan, energy researcher and Breaking Bad actor February 14, 2013 - 12:36pm Addthis Marius Stan, computational energy scientist from Argonne National Lab, submits his verification photo as part of an informal question and answer session with Internet users on the Ask Me Anything section of the social website Reddit. Marius Stan, computational energy scientist from Argonne National Lab, submits his verification photo as part of an informal question and answer session with Internet users on the Ask Me Anything section of the social website Reddit. Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs What is an Reddit AMA? AMA stands for "Ask me anything."

178

The prompt emission & peculiar break of GRB 060124  

E-Print Network (OSTI)

Our multi-wavelength analysis of GRB 060124 shows the unusual behaviour of the decaying lightcurve as well as supporting the recently proposed phenomenon of long-lasting central engine activity. The prompt X-ray emission displays uncommonly well resolved flaring behaviour, with spectral evolution - indicative of central engine activity - which allows us to estimate the energy injection time for each flare. The otherwise smooth X-ray & optical afterglows demonstrate achromatic breaks at about 1 day which differ significantly from the usual jet break in the blastwave model of afterglows.

P. A. Curran; D. A. Kann; P. Ferrero; E. Rol; R. A. M. J. Wijers

2006-10-03T23:59:59.000Z

179

Dynamical SUSY Breaking and the Beta-Deformation  

E-Print Network (OSTI)

We study supersymmetry breaking metastable vacua arising from beta deformed quiver gauge theories. The relation between the bounds on metastability and the deformation are discussed. Metastable supersymmetry breaking vacua are found in the IR of beta deformed cascading quivers with vector-like field content. Furthermore the limiting case of massive Nf=Nc SQCD appears in the IR of gauge theories with chiral-like field content. We comment on the field theory origin of the deformation and on possible applications in AdS/CFT.

Amariti, A

2010-01-01T23:59:59.000Z

180

Measurements of Temperature Fluctuations in Breaking Surface Waves  

Science Conference Proceedings (OSTI)

Measurements of temperature fluctuations and air entrainment within the upper 1 m of the surface caused by breaking surface waves have been acquired with a novel surface-following sensor array. Brief temperature fluctuations of order 20 mK–100 mK ...

David M. Farmer; Johannes R. Gemmrich

1996-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Small break LOCA analysis for Maanshan nuclear power plant  

SciTech Connect

Since 1990, Taiwan Power Company has conducted a LWR LOCA technology transfer program on RELAP5YA computer code from Yankee Atomic Electric Company (YAEC). One objective of this program is to acquire the RELAP5YA computer code from YAEC for Taipower in-house licensing analysis. The RELAP5YA is a computer program developed at YAEC for analysing the dynamic behaviour of thermal-hydraulic systems, and it can cover most of the postulated accidents and transients in light water reactor systems. In this paper, Taipower`s engineers have performed a small break loss of coolant accidents analysis for Maanshan nuclear power plant. Thais action is used to perform the licensing actions for increasing the operation margin on the steam generator tube plugging. The result is shown that the steam generator tube can be plugged slightly without a reduction in safety margins. This analysis covers a spectrum of break size for a small break LOCA. For a complete spectrum of the transient and accident analysis, the large break LOCA and the non-LOCA analysis were performed by the fuel vendor for the reload safety evaluation.

Jer-Cherng Kang; Shou-Chuan Chiang; Lang-Chen Wang [Taiwan Power Company, Taipei (China)

1994-12-31T23:59:59.000Z

182

The far-UV break in quasar energy distributions: dust?  

E-Print Network (OSTI)

A prominent continuum steepening is observed in quasar energy distributions near 1100A. We review possible interpretations for the origin of the so-called far-UV break, putting emphasis on those that favor the emergence of an upturn in the extreme-UV.

L. Binette; Y. Krongold; S. Haro-Corzo; A. Andersen

2006-11-01T23:59:59.000Z

183

Spectral Energy Balance of Breaking Waves within the Surf Zone  

Science Conference Proceedings (OSTI)

The spectral energy balance of ocean surface waves breaking on a natural beach is examined with field observations from a cross-shore array of pressure sensors deployed between the shoreline and the outer edge of the surf zone near Duck, North ...

T. H. C. Herbers; N. R. Russnogle; Steve Elgar

2000-11-01T23:59:59.000Z

184

The Link between Rossby Wave Breakings and Weather Regime Transitions  

Science Conference Proceedings (OSTI)

The link between Rossby wave breaking (RWB) and the four wintertime weather regimes over the North Atlantic domain is studied in this paper. Using the 40-yr ECMWF Re-Analysis (ERA-40) data, frequencies of occurrence of anticyclonic and cyclonic ...

Clio Michel; Gwendal Rivière

2011-08-01T23:59:59.000Z

185

Wave Breaking Dissipation in the Wave-Driven Ocean Circulation  

Science Conference Proceedings (OSTI)

If wave breaking modifies the Lagrangian fluid paths by inducing an uncertainty in the orbit itself and this uncertainty on wave motion time scales is observable as additive noise, it is shown that within the context of a wave–current interaction ...

Juan M. Restrepo

2007-07-01T23:59:59.000Z

186

Aeration Due to Breaking Waves. Part I: Bubble Populations  

Science Conference Proceedings (OSTI)

The population of bubbles produced by breaking waves in (10 m) winds of up to 12 m s?1 is analyzed using calibrated images from a vertical pencil-beam sonar system placed on the seabed near the Dutch coast. The structure in the images is ...

A. Graham; D. K. Woolf; A. J. Hall

2004-05-01T23:59:59.000Z

187

Near-Surface Turbulence in the Presence of Breaking Waves  

Science Conference Proceedings (OSTI)

Observations with a three-axis pulse-to-pulse coherent acoustic Doppler profiler and acoustic resonators reveal the turbulence and bubble field beneath breaking waves in the open ocean at wind speeds up to 14 m s?1. About 55%–80% of velocity ...

Johannes R. Gemmrich; David M. Farmer

2004-05-01T23:59:59.000Z

188

Gravity Wave Breaking in Two-Layer Hydrostatic Flow  

Science Conference Proceedings (OSTI)

To better understand mountain-induced gravity wave breaking and potential vorticity generation in the troposphere, a two-layer hydrostatic flow over a three-dimensional Witch-of-Agnesi type of mountain is investigated. It is suggested that a two-...

Qingfang Jiang; Ronald B. Smith

2003-05-01T23:59:59.000Z

189

Gas exploration and oceanography beyond the shelf break  

E-Print Network (OSTI)

Gas exploration and oceanography beyond the shelf break Ã?. Thiem1 , J. Berntsen1,2 , G. Alendal2 cause problems for installations needed for exploration of the gas field. Bergen Ocean Model (BOM) has for Computational Science, University of Bergen, Norway 3 Norsk Hydro, Oil & Energy, Research Center, Bergen, Norway

Thiem, Ã?yvind

190

Gas exploration beyond the shelf break: An oceanographic challenge  

E-Print Network (OSTI)

Gas exploration beyond the shelf break: An oceanographic challenge Ã?. Thiema, *, J. Berntsena,b , T industries point of view, this research has been of limited interest since the oil and gas fields have been, 5059 Bergen, Norway Available online 24 December 2004 Abstract Norway's second largest gas field, Ormen

Thiem, Ã?yvind

191

The DNA project - CECM  

E-Print Network (OSTI)

Software-package files: dna6.zip (for Maple 6), dna7.zip (for Maple 7). Contents: DNA routines, Release 1.04 ( last updated Nov/06/2001 ). Changes over ...

192

Breaks in the Asian Monsoon: The Influence of Southern Hemisphere Weather Systems  

Science Conference Proceedings (OSTI)

Atmospheric model results suggest that chaotic weather systems in the Southern Hemisphere midlatitudes can trigger “breaks” in the Indian monsoon rainfall. Indeed, the mechanism may be able to trigger a more general break of the entire Asian ...

Mark J. Rodwell

1997-11-01T23:59:59.000Z

193

Three dimensional effects in analysis of PWR steam line break accident  

E-Print Network (OSTI)

A steam line break accident is one of the possible severe abnormal transients in a pressurized water reactor. It is required to present an analysis of a steam line break accident in the Final Safety Analysis Report (FSAR) ...

Tsai, Chon-Kwo

194

Experimental Investigation of Wave Breaking Criteria Based on Wave Phase Speeds  

Science Conference Proceedings (OSTI)

Experiments were performed that test the kinematic breaking criterion, which states that the horizontal fluid particle velocity at the surface of a crest exceeds the local phase speed of the crest prior to breaking. Three different definitions of ...

Paul Stansell; Colin MacFarlane

2002-05-01T23:59:59.000Z

195

Bubbles Help Break Energy Storage Record for Lithium Air-Batteries  

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

Bubbles Help Break Energy Storage Record for Lithium Air-Batteries Bubbles Help Break Energy Storage Record for Lithium Air-Batteries Foam-base graphene keeps oxygen flowing in...

196

Spectral Distribution of Energy Dissipation of Wind-Generated Waves due to Dominant Wave Breaking  

Science Conference Proceedings (OSTI)

This paper considers an experimental attempt to estimate the spectral distribution of the dissipation due to breaking of dominant waves. A field wave record with an approximately 50% dominant-breaking rate was analyzed. Segments of the record, ...

Ian R. Young; Alexander V. Babanin

2006-03-01T23:59:59.000Z

197

Modulational Instabilities and Breaking Strength for Deep-Water Wave Groups  

Science Conference Proceedings (OSTI)

Progression of nonlinear wave groups to breaking was studied numerically and experimentally. Evolution of such wave group parameters as a function of distance to breaking and modulation depth—the height ratio of the highest and the lowest waves ...

Alina Galchenko; Alexander V. Babanin; Dmitry Chalikov; I. R. Young; Tai-Wen Hsu

2010-10-01T23:59:59.000Z

198

Experimental investigation of small-scale breaking waves : flow visualization across the air-water interface  

E-Print Network (OSTI)

The dynamics of breaking waves significantly affect air-sea fluxes of heat, momentum, mass and energy across the ocean interface. Breaking waves also contribute considerable loading to offshore and coastal structures, and ...

McDonald, Angus Kai

2005-01-01T23:59:59.000Z

199

DOE Joint Genome Institute: Breaking down cellulose without blasting  

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

4, 2011 4, 2011 Breaking down cellulose without blasting lignin: "Dry rot" genome offers lessons for biofuel pretreatment WALNUT CREEK, Calif.-Feared by realtors and homeowners alike, dry rot due to the fungus Serpula lacrymans causes millions of dollars worth of damage to homes and buildings around the world. This brown rot fungus' capacity to break down the cellulose in wood led to its selection for sequencing by the U.S. Department of Energy (DOE) Joint Genome Institute (JGI) in 2007, with the goal of identifying the enzymes involved in the degradation process and using the information to improve cellulosic biofuels production. Photo: A variant of Serpula lacrymans causes dry rot. (Dave Brown via Flickr/Creative Commons Attribution 2.0) As reported online July 14 in Science Express, an international team of

200

Are vortices in rotating superfluids breaking the Weak Equivalence Principle?  

E-Print Network (OSTI)

Due to the breaking of gauge symmetry in rotating superfluid Helium, the inertial mass of a vortex diverges with the vortex size. The vortex inertial mass is thus much higher than the classical inertial mass of the vortex core. An equal increase of the vortex gravitational mass is questioned. The possibility that the vortices in a rotating superfluid could break the weak equivalence principle in relation with a variable speed of light in the superfluid vacuum is debated. Experiments to test this possibility are investigated on the bases that superfluid Helium vortices would not fall, under the single influence of a uniform gravitational field, at the same rate as the rest of the superfluid Helium mass.

Clovis Jacinto de Matos

2009-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Acceleration of the cosmic expansion induced by symmetry breaking  

E-Print Network (OSTI)

It is proved that in order to obtain a model of the accelerated cosmic expansion the thing one only need to do is to add a perturbation term to the Einstein-Hilbert Lagrangian. This term leads to some symmetry breaking terms in the fields equation, which makes the cosmic expansion accelerating. A vacuum de Sitter solution is obtained. A new explanation of the acceleration of the cosmic expansion is presented. In this model the changing of the expansion from decelerating to accelerating is an intrinsic property of the universe without need of an exotic dark energy. The acceleration of the cosmic expansion is induced by the symmetry breaking perturbation of the gravitational energy. The cosmological constant problem, the coincidence problem and the problem of phantom divide line crossing are naturally solved. The results of the model are roughly consistent with the observations.

G. Y. Chee

2013-01-21T23:59:59.000Z

202

Clinical DNA Online  

Science Conference Proceedings (OSTI)

Welcome to the NIST Clinical DNA Information Resource. ... Future materials have progress updates. General Information. ...

2013-04-26T23:59:59.000Z

203

Quantitative DNA fiber mapping  

DOE Patents (OSTI)

The present invention relates generally to the DNA mapping and sequencing technologies. In particular, the present invention provides enhanced methods and compositions for the physical mapping and positional cloning of genomic DNA. The present invention also provides a useful analytical technique to directly map cloned DNA sequences onto individual stretched DNA molecules.

Gray, Joe W. (San Francisco, CA); Weier, Heinz-Ulrich G. (Oakland, CA)

1998-01-01T23:59:59.000Z

204

Modeling the Propagation, Breaking and Drift of Ocean Surface Wave  

E-Print Network (OSTI)

A new model other than the classical ones given by Airy, Stokes and Gerstner for the ocean surface wave is constructed. It leads to new understandings for the wave mechanisms: (1) A wave with bigger amplitude or smaller steepness travels faster; (2) The wave breaks when the front angle is bigger than 46.3 degree; (3) The magnitude of the wave drift should be smaller than that of the known Stokes drift.

Jin-Liang Wang

2013-04-03T23:59:59.000Z

205

Electroweak and supersymmetry breaking from the Higgs discovery  

E-Print Network (OSTI)

We will explore the consequences on the electroweak breaking condition, the mass of supersymmetric partners and the scale at which supersymmetry is broken, for arbitrary values of the supersymmetric parameters tan(beta) and the stop mixing X_t, which follow from the Higgs discovery with a mass m_H\\simeq 126 GeV at the LHC. Within the present uncertainty on the top quark mass we deduce that radiative breaking requires tan(beta) \\gtrsim 7 for maximal mixing X_t\\simeq \\sqrt{6}, and tan(beta) \\gtrsim 20 for small mixing X_t\\lesssim 1. The scale at which supersymmetry is broken \\mathcal M can be of order the unification or Planck scale only for large values of tan(beta) and negligible mixing X_t\\simeq 0. On the other hand for maximal mixing and large values of tan(beta) supersymmetry should break at scales as low as \\mathcal M\\simeq 10^5 GeV. The uncertainty in those predictions stemming from the uncertainty in the top quark mass, i.e. the top Yukawa coupling, is small (large) for large (small) values of tan(beta). In fact for tan(beta)=1 the uncertainty on the value of \\mathcal M is of several orders of magnitude.

Antonio Delgado; Mateo Garcia; Mariano Quiros

2013-12-11T23:59:59.000Z

206

Low Dose Radiation Research Program: Robert L. Ullrich  

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

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

207

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

208

Cells Forming Blood Vessels Send Their Copper to the Edge | Advanced Photon  

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

A Molecular Cause for One Form of Deafness A Molecular Cause for One Form of Deafness Water Theory is Watertight Nanowire Micronetworks from Carbon-Black Nanoparticles A Key Step in Repairing DNA Double-Strand Breaks An X-ray Rainbow 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 Cells Forming Blood Vessels Send Their Copper to the Edge FEBRUARY 20, 2007 Bookmark and Share Areas at the tips of HMVEC filopodia extensions were scanned by XFM at high resolution. The optical image is shown to the right and metal maps are shown to the left. False color images of P, Cu, and Zn are shown in the red, green and blue images respectively, and their overlay is shown to the lower right, demonstrating a transfer of cellular copper across the cell

209

A Molecular Cause for One Form of Deafness | Advanced Photon Source  

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

Water Theory is Watertight Water Theory is Watertight Nanowire Micronetworks from Carbon-Black Nanoparticles A Key Step in Repairing DNA Double-Strand Breaks An X-ray Rainbow An Insulating Breakthrough 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 A Molecular Cause for One Form of Deafness FEBRUARY 12, 2007 Bookmark and Share Gerard Wong, a professor of materials science and engineering, of physics, and of bioengineering at Illinois, and colleagues have found an underlying molecular cause for one form of deafness, while exploring the physics of hearing. (Photo by L. Brian Stauffer) Scientists exploring the physics of hearing have found an underlying molecular cause for one form of deafness, and a conceptual connection

210

Dynamics of Wave Breaking at a Coastal Sea Wall  

E-Print Network (OSTI)

Structural designs barely consider the dynamic scenario of a well-developed impinging wave hitting the structure. The usual area of focus is on static and stability factors (e.g. drag, inertia, resistive forces related to weight, buoyancy, sliding etc). Even the "Factor of Safety" which is regularly used in designs to account for unknown and/or unforeseen situations which might occur implies a degree of uncertainty about the dynamic scenario of breaking waves in the coastal environment. In the present study the hydrodynamics of a coastal structure-turbulent bore interaction was studied by examination (two-dimensional) of the singular case of a plunging breaking wave forming a well developed turbulent bore which impacted on a model sea wall structure. The turbulent bore impact event was found to display similar characteristics to the impact event of other wave shapes, in particular that of a plunging breaker. Examination of the impact event confirmed the conversion of nearly all horizontal velocity to vertical velocity during the "flip through" event. In accordance with theoretical expectations the location of maximum pressure was found to occur just below the still water level (SWL). Resulting pressure data in the present study consisted of two blunt spikes as opposed to the "church-roof" (high spike) shape seen in other results. The shape of the pressure data was attributed to the following: firstly, to the initial impact of the protruding jet of the breaking wave which causes the first maxima, secondly, to the sensor encountering the bulk of the entrapped air hence causing the drop in pressure between the blunt spikes and lastly, to the inherent hydrostatic pressure combined with the compression of the entrapped air bubbles, by the subsequent forward motion of the water within the wave, which causes the second maxima. The point of maximum pressure was found to always be within the second maxima. Observation of the turbulent bore-structure interaction showed that the consequential maximum pressure was a direct result of the compression of entrapped air by the weight of the water in the wave as it continued forward onto the structure combined with the inherent hydrostatic pressure of the wave. The project was conducted in an attempt to contribute to the vast knowledge of coastal structure-wave interactions and to add to the understanding of the physics and characteristics of breaking waves. Whilst numerous studies and experiments have been carried out on the phenomenon of breaking waves by previous researchers the current project highlights the advent of new equipment and technological advances in existing methods.

Antoine, Arthur L.

2009-12-01T23:59:59.000Z

211

Chiral symmetry breaking revisited: the gap equation with lattice ingredients  

Science Conference Proceedings (OSTI)

We study chiral symmetry breaking in QCD, using as ingredients in the quark gap equation recent lattice results for the gluon and ghost propagators. The Ansatz employed for the quark-gluon vertex is purely non-Abelian, introducing a crucial dependence on the ghost dressing function and the quark-ghost scattering amplitude. The numerical impact of these quantities is considerable: the need to invoke confinement explicitly is avoided, and the dynamical quark masses generated are of the order of 300 MeV. In addition, the pion decay constant and the quark condensate are computed, and are found to be in good agreement with phenomenology.

Aguilar, Arlene C. [Federal University of ABC, CCNH, Rua Santa Adelia 166, CEP 09210-170, Santo Andre (Brazil)

2011-05-23T23:59:59.000Z

212

Phenomenological issues in supersymmetry with nonholomorphic soft breaking  

SciTech Connect

We present a through discussion of motivations for and phenomenological issues in supersymmetric models with minimal matter content and nonholomorphic soft-breaking terms. Using the unification of the gauge couplings and assuming SUSY is broken with nonstandard soft terms, we provide semianalytic solutions of the RGEs for low and high choices of tan{beta} which can be used to study the phenomenology in detail. We also present a generic form of RGIs in mSUGRA framework which can be used to derive new relations in addition to those existing in the literature. Our results are mostly presented with respect to the conventional minimal supersymmetric model for ease of comparison.

Cakir, M.A.; Mutlu, S.; Solmaz, L. [Department of Physics, Izmir Institute of Technology, IZTECH, TR35430 (Turkey); Department of Physics, Balikesir University, Balikesir, TR10100 (Turkey)

2005-06-01T23:59:59.000Z

213

Constraint on the (GUT) symmetry breaking scale and topological defects  

Science Conference Proceedings (OSTI)

In F-term supergravity inflation models, scalar fields other than the inflaton generically receive a Hubble induced mass, which may restore gauge symmetries during inflation and phase transitions may occur during or after inflation as the Hubble parameter decreases. We study topological defect formation associated with such a phase transition in chaotic inflation in supergravity and obtain a severe constraint on the symmetry breaking scale which is related with the tensor-to-scalar ratio. This talk is based on the paper [1].

Kamada, Kohei; Nakayama, Kazunori; Yokoyama, Jun'ichi [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Department of Physics, Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan); Research Center for the Early Universe (RESCEU), Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan) and Kavli institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Kashiwa, Chiba, 277-8568 (Japan)

2012-07-27T23:59:59.000Z

214

How scientists use DNA  

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

How scientists use DNA Name: Peter and Edmund Age: NA Location: NA Country: NA Date: NA Question: Dear Scientists, We would like to know some ways that scientists use DNA. For...

215

DNA and Biometrics  

Science Conference Proceedings (OSTI)

... January 17, 2008 Press Release From Mayor Bloomberg's STATE OF THE CITY ADDRESS Efforts towards Portable/Mobile DNA Devices ...

2008-06-25T23:59:59.000Z

216

Intrinsic transverse momentum and dynamical chiral symmetry breaking  

Science Conference Proceedings (OSTI)

We study the effect of QCD vacuum structure on the intrinsic transverse momentum distribution of partons in the nucleon at a low scale. The dynamical breaking of chiral symmetry is caused by non-perturbative interactions at distances of the order rho ~ 0.2 - 0.3 fm, much smaller than the typical nucleon size R ~ 1 fm, resulting in a two-scale picture of nucleon structure. Using an effective dynamical model based on chiral constituent quark degrees of freedom and the 1/N_c expansion (chiral quark-soliton model), we calculate the transverse momentum distribution of quarks and antiquarks at a low scale. The distribution of valence quarks is localized at p_T ~ 1/R. The distribution of flavor-singlet unpolarized sea quarks exhibits a power-like tail extending up to the chiral-symmetry-breaking scale 1/{rho}. A similar tail is present in the flavor-nonsinglet polarized sea. These features are model-independent and represent the imprint of the QCD vacuum on the nucleon's partonic structure. At the level of the nucleon's light-cone wave function, we show that sea quarks partly exist in correlated pairs of transverse size {rho} << R, analogous to short-range NN correlations in nuclei. We discuss the implications of our findings for the transverse momentum distributions in hard scattering processes (semi-inclusive DIS, Drell-Yan pair production) and possible experimental tests of the non-perturbative parton correlations induced by QCD vacuum structure.

Christian Weiss, Peter Schweitzer, Mark Strikman

2013-01-01T23:59:59.000Z

217

Intermediate-break LOCA analyses for the AP600 design  

Science Conference Proceedings (OSTI)

A postulated double-ended guillotine break of a direct-vessel-injection line in an AP600 plant has been analyzed. This event is characterized as an intermediate break loss-of-coolant accident (IBLOCA). Most of the insights regarding the response of the AP600 safety systems to the postulated accident are derived from calculations performed with the TRAC-PFl/MOD2 code. However, complementary insights derived from a scaled experiment conducted in the ROSA facility, as well as insights based upon calculations by other codes, are also presented. The key processes occurring in an AP600 during a IBLOCA are primary coolant system depressurization, inventory depletion, inventory replacement via emergency core coolant injection, continuous core cooling, and long-term decay heat rejection to the atmosphere. Based upon the calculated and experimental results, the AP600 will not experience a core heat up and will reach a safe shutdown state using only safety-class equipment. Only the early part of the long-term cooling period initiated by In-containment Refueling Water Storage Tank injection was evaluated Thus, the observation that the core is continuously cooled should be verified for the latter phase of the long-term cooling period, the interval when sump injection and containment cooling processes are important.

Boyack, B.E.; Lime, J.F.

1995-07-01T23:59:59.000Z

218

CSNI specialist meeting on leak-before-break in nuclear reactor piping: proceedings  

SciTech Connect

On September 1 and 2, 1983, the CSNI subcommittee on primary system integrity held a special meeting in Monterey, California, on the subject of leak-before-break in nuclear reactor piping systems. The purpose of the meeting was to provide an international forum for the exchange of ideas, positions, and research results; to identify areas requiring additional research and development; and to determine the general attitude toward acceptance of the leak-before-break concept. The importance of the leak-before-break issue was evidenced by excellent attendance at the meeting and through active participation by the meeting attendees. Approximately 125 people representing fifteen different nations attended the meeting. The meeting was divided into four technical sessions addressing the following areas: Application of Piping Fracture Mechanics to Leak-Before Break, Leak Rate and Leak Detection, Leak-Before-Break Studies, Methods and Results, Current and Proposed Positions on Leak-Before-Break.

Not Available

1984-08-01T23:59:59.000Z

219

ON THE EVOLUTION OF THE SPECTRAL BREAK IN THE AFTERGLOW OF GAMMA-RAY BURSTS  

Science Conference Proceedings (OSTI)

The temporal evolution of the spectral break in the time-resolved spectral energy density of the broadband afterglow of gamma-ray bursts (GRBs) 091127 and 080319B was shown recently to be inconsistent with that expected for the cooling break in the standard fireball model of GRBs. Here we show that it is, however, in good agreement with the predicted temporal evolution of the smooth injection break/bend in the cannonball model of GRBs.

Dado, Shlomo; Dar, Arnon [Physics Department, Technion, Haifa 32000 (Israel)

2012-02-20T23:59:59.000Z

220

Comments on the leak-before-break concept for nuclear power plant piping systems  

SciTech Connect

The leak-before-break concept is based on the idea that, with a high degree of probability, failure of the pressure boundary of piping systems will be signaled by a detectable leak that will provide ample time to shutdown and repair that leak. The status of the leak-before-break concept is discussed in this report, including a review of industrial and nuclear power plant experience with respect to leak-before-break, fracture mechanics, and potential elimination of postulated pipe breaks in nuclear power plant piping design. 36 refs., 12 figs., 3 tabs.

Rodabaugh, E.C.

1985-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

The vascular flora of Breaks Interstate Park, Pike County, Kentucky, and Dickenson County, Virginia.  

E-Print Network (OSTI)

??The vascular flora of Breaks Interstate Park was documented during two growing seasons, 2008 and 2009; with supplemental collections made in 2010 and 2011. The… (more)

Clark, Julie Bennett

2012-01-01T23:59:59.000Z

222

LANL breaks ground on key sediment control project  

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

Sediment control project Sediment control project LANL breaks ground on key sediment control project Called "grade-control" structures, the approximately $2 million features are up to eight feet high and made of rocks packed tightly into wire enclosures. November 5, 2009 Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials. Los Alamos National Laboratory sits on top of a once-remote mesa in northern New Mexico with the Jemez mountains as a backdrop to research and innovation covering multi-disciplines from bioscience, sustainable energy sources, to plasma physics and new materials.

223

A Symmetry Breaking Model for X Chromosome Inactivation  

E-Print Network (OSTI)

In mammals, dosage compensation of X linked genes in female cells is achieved by inactivation of one of their two X chromosomes which is randomly chosen. The earliest steps in X-inactivation (XCI), namely the mechanism whereby cells count their X chromosomes and choose between two equivalent X, remain mysterious. Starting from the recent discovery of X chromosome colocalization at the onset of X-inactivation, we propose a Statistical Mechanics model of XCI, which is investigated by computer simulations and checked against experimental data. Our model describes how a `blocking factor' complex is self-assembled and why only one is formed out of many diffusible molecules, resulting in a spontaneous symmetry breaking (SB) in the binding to two identical chromosomes. These results are used to derive a scenario of biological implications describing all current experimental evidences, e.g., the importance of colocalization.

M. Nicodemi; A. Prisco

2008-01-17T23:59:59.000Z

224

When Size Matters: Yttrium Oxide Breaking Down Under Pressure | Advanced  

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

Breakthrough in Nanocrystals' Growth Breakthrough in Nanocrystals' Growth Next Step to Drought-Resistant Plants? A Boring Material "Stretched" Could Lead to an Electronics Revolution At the Crossroads of Chromosomes Unveiling the Structure of Adenovirus 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 When Size Matters: Yttrium Oxide Breaking Down Under Pressure NOVEMBER 2, 2010 Bookmark and Share Top: Pair distribution function (PDF) of 16 nm-sized Y2O3 at high pressures. Bottom: Lin Wang (left) and Wenge Yang (right) of the Carnegie Institution of Washington shown with the diamond anvil cell and x-ray instrumentation used to probe the PDF of the sample at high applied

225

Breaking Records in Neurological Microradiology | Advanced Photon Source  

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

Exposing Valence-Bond Model Inadequacies Exposing Valence-Bond Model Inadequacies Plants' Rapid Response System Revealed Rewriting the Organofluorine Playbook Computer-Designed Proteins to Disarm a Variety of Flu Viruses Driving Membrane Curvature 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 Breaking Records in Neurological Microradiology AUGUST 9, 2012 Bookmark and Share A dense neuron cluster including details of cells in deeper tissue layers. As neuroscientists probe ever deeper into the mysteries of the brain and nervous system, they need ever sharper vision. A group of researchers has developed some exciting new techniques for imaging neuronal and synaptic networks using the hard synchrotron x-rays

226

Universality and Symmetry Breaking in Conformally Reduced Quantum Gravity  

E-Print Network (OSTI)

The scaling properties of quantum gravity are discussed by employing a class of proper-time regulators in the functional flow equation for the conformal factor within the formalism of the background field method. Renormalization group trajectories obtained by projecting the flow on a flat topology are more stable than those obtained from a projection on a spherical topology. In the latter case the ultraviolet flow can be characterized by a Hopf bifurcation with an ultraviolet attractive limiting cycle. Although the possibility of determining the infrared flow for an extended theory space can be severely hampered due to the conformal factor instability, we present a robust numerical approach to study the flow structure around the non-gaussian fixed point as an inverse-problem strategy. In particular it is shown the possibility of having a spontaneous breaking of the diffeomorphism invariance can be realized with non-local functionals of the volume operator.

Bonanno, Alfio

2012-01-01T23:59:59.000Z

227

Breaking Up Breaking Up  

E-Print Network (OSTI)

Administration EPRI Electric Power Research Institute EV Electric Vehicle FERC Federal Energy Regulatory (FERC) Chairman Jon Wellinghoff has called demand response the "killer app" of the smart grid (FERC of households. A study prepared for FERC estimated that demand response programs, if fully deployed, could cut U

de Lijser, Peter

228

Loss of ATM Function Enhances Recombinant Adeno-Associated Virus Transduction and Integration through Pathways Similar to UV Irradiation  

E-Print Network (OSTI)

as double-stranded breaks occurs frequently on exposure to chemical carcinogens and radiation *Departments of Anatomy and Cell Biology and of Internal Medicine, Center for Gene Therapy, and Department and ionizing radiation ap- pears to be altered in AT patients, because the onset of p53 activation is delayed

Engelhardt, John F.

229

Patterning nanocrystals using DNA  

E-Print Network (OSTI)

nanocrystals. Angewandte Chemie-International Edition, [2]linked by DNA. Angewandte Chemie-International Edition, 39(with proteins. Angewandte Chemie-International Edition, 40(

Williams, Shara Carol

2003-01-01T23:59:59.000Z

230

Effects of Wave Breaking on the Near-Surface Profiles of Velocity and Turbulent Kinetic Energy  

Science Conference Proceedings (OSTI)

A theoretical model for the near-surface velocity profile in the presence of breaking waves is presented. Momentum is accumulated by growing waves and is released upon wave breaking. In effect, such a transition is a process involving a time-...

Arne Melsom; Øyvind SÆtra

2004-02-01T23:59:59.000Z

231

A particle-based method for large-scale breaking waves simulation  

Science Conference Proceedings (OSTI)

We address in this paper the problem of particle-based simulation of breaking waves. We present a new set of equations based on oceanographic research which allow us to deal with several types of breaking waves and multiple wave trains with full control ...

Emmanuelle Darles; Benoit Crespin; Djamchid Ghazanfarpour

2010-09-01T23:59:59.000Z

232

WaveTurbulence Interactions in a Breaking Mountain Wave CRAIG C. EPIFANIO AND TINGTING QIAN  

E-Print Network (OSTI)

-breaking calculations. Of particular interest are the turbulent heat and momentum fluxes in the breaking wave fluxes on grid spacing is considered by computing a series of ensembles with grid spacings ranging from L are mostly resolved, but with increasing grid spacing, the resolved-scale fluxes decline

233

Break-Even Cost for Residential Photovoltaics in the United States: Key Drivers and Sensitivities  

DOE Green Energy (OSTI)

Grid parity--or break-even cost--for photovoltaic (PV) technology is defined as the point where the cost of PV-generated electricity equals the cost of electricity purchased from the grid. Break-even cost is expressed in $/W of an installed system. Achieving break-even cost is a function of many variables. Consequently, break-even costs vary by location and time for a country, such as the United States, with a diverse set of resources, electricity prices, and other variables. In this report, we analyze PV break-even costs for U.S. residential customers. We evaluate some key drivers of grid parity both regionally and over time. We also examine the impact of moving from flat to time-of-use (TOU) rates, and we evaluate individual components of the break-even cost, including effect of rate structure and various incentives. Finally, we examine how PV markets might evolve on a regional basis considering the sensitivity of the break-even cost to four major drivers: technical performance, financing parameters, electricity prices and rates, and policies. We find that local incentives rather than ?technical? parameters are in general the key drivers of the break-even cost of PV. Additionally, this analysis provides insight about the potential viability of PV markets.

Denholm, P.; Margolis, R. M.; Ong, S.; Roberts, B.

2009-12-01T23:59:59.000Z

234

Photo of the Week: Record-Breaking Solar Cells | Department of Energy  

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

Record-Breaking Solar Cells Record-Breaking Solar Cells Photo of the Week: Record-Breaking Solar Cells December 7, 2012 - 2:27pm Addthis Solar Junction, in partnership with NREL, has developed solar cells that reach a record-breaking 44 percent efficiency -- meaning that more than 40 percent of the sunlight the solar cells are exposed to is converted into electrical energy. In this photo, an operator inspects a photolithography tool used to manufacture these solar cells. | Photo by Daniel Derkacs/SolarJunction. Solar Junction, in partnership with NREL, has developed solar cells that reach a record-breaking 44 percent efficiency -- meaning that more than 40 percent of the sunlight the solar cells are exposed to is converted into electrical energy. In this photo, an operator inspects a photolithography

235

Photo of the Week: Record-Breaking Solar Cells | Department of Energy  

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

Photo of the Week: Record-Breaking Solar Cells Photo of the Week: Record-Breaking Solar Cells Photo of the Week: Record-Breaking Solar Cells December 7, 2012 - 2:27pm Addthis Solar Junction, in partnership with NREL, has developed solar cells that reach a record-breaking 44 percent efficiency -- meaning that more than 40 percent of the sunlight the solar cells are exposed to is converted into electrical energy. In this photo, an operator inspects a photolithography tool used to manufacture these solar cells. | Photo by Daniel Derkacs/SolarJunction. Solar Junction, in partnership with NREL, has developed solar cells that reach a record-breaking 44 percent efficiency -- meaning that more than 40 percent of the sunlight the solar cells are exposed to is converted into electrical energy. In this photo, an operator inspects a photolithography

236

Controlling DNA Methylation  

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

Controlling DNA Methylation Though life on earth is composed of a diverse range of organisms, some with many different types of tissues and cells, all these are encoded by a molecule we call DNA. The information required to build a protein is stored in DNA within the cells. Not all the message in the DNA is used in each cell and not all the message is used all the time. During cell differentiation, the cells become dedicated for their specific function which involves selectively activating some genes and repressing others. Gene regulation is an important event in the developmental biology and the biology of various diseases, but a more complex process. Controlling DNA Methylation Though life on earth is composed of a diverse range of organisms, some with many different types of tissues and cells, all these are encoded by a molecule we call DNA. The information required to build a protein is stored in DNA within the cells. Not all the message in the DNA is used in each cell and not all the message is used all the time. During cell differentiation, the cells become dedicated for their specific function which involves selectively activating some genes and repressing others. Gene regulation is an important event in the developmental biology and the biology of various diseases, but a more complex process. In the bacteria there are distinct enzymes while one is capable of cleaving DNA, the other protects DNA by modification. The complementary function provided by the set of enzymes offers a defense mechanism against the phage infection and DNA invasion. The incoming DNA is cleaved sequence specifically by the class of enzymes called restriction endonuclease (REase). The host DNA is protected by the sequence specific action of matching set of enzymes called the DNA methyltransferase (MTase). The control of the relative activities of the REase and MTase is critical because a reduced ratio of MTase/REase activity would lead to cell death via autorestriction. However too high a ratio would fail to provide protection against invading viral DNA. In addition a separate group of proteins capable of controlling R-M proteins have been identified in various restriction-modification (R-M) systems which are called C proteins (Roberts et al., 2003).

237

DNA's Role with Proteins  

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

DNA's Role with Proteins DNA's Role with Proteins Name: Hans Location: N/A Country: N/A Date: N/A Question: Is it sure that the most important information of living cells is stored in the DNA? DNA seems to be nothing more than an inventory of useful proteins and a tool to create those proteins. Could it be that more important operational know how of how these proteins interact to build a living organism is actually located in the rest of the cell? So that the rest of the cell is the most important inheritance, whereas DNA merely takes care of the genetic variation? Replies: DNA is the entire library of protein information for an organism. All seven types of protein. It is true that in developmental stages of an organism that the presence and absences of certain proteins and other chemicals generated by proteins will influence what the DNA in a "particular" cell will express. Hence, you can start out with one cell and end up with a complex organism. You may have heard some of this information with the cloning activities that have been going on lately. All the inheritance comes from the DNA, but what parts of the DNA expression may be dictated by the cells special characteristics developed upon specializing. In that way the liver cells will only do "liver" things and the kidney cells will only do "kidney" things, BUT they use the same DNA information to operate, just a different portion of the same DNA that pertains to their particular "job". If you can convince a cell that it does not have a special job anymore, then you can develop the entire organism from this cell with the right signals; this is what cloning techniques have done!

238

TopBP1 associates with NBS1 and is involved in homologous recombination repair  

SciTech Connect

TopBP1 is involved in DNA replication and DNA damage checkpoint. Recent studies have demonstrated that TopBP1 is a direct positive effecter of ATR. However, it is not known how TopBP1 recognizes damaged DNA. Here, we show that TopBP1 formed nuclear foci after exposure to ionizing radiation, but such TopBP1 foci were abolished in Nijmegen breakage syndrome cells. We also show that TopBP1 physically associated with NBS1 in vivo. These results suggested that NBS1 might regulate TopBP1 recruitment to the sites of DNA damage. TopBP1-depleted cells showed hypersensitivity to Mitomycin C and ionizing radiation, an increased frequency of sister-chromatid exchange level, and a reduced frequency of DNA double-strand break induced homologous recombination repair. Together, these results suggested that TopBP1 might be a mediator of DNA damage signaling from NBS1 to ATR and promote homologous recombination repair.

Morishima, Ken-ichi [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan); Sakamoto, Shuichi; Kobayashi, Junya [Department of Genome Dynamics, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan); Izumi, Hideki; Suda, Tetsuji; Matsumoto, Yoshiyuki [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan); Tauchi, Hiroshi [Department of Environmental Sciences, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Ide, Hiroshi [Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8562 (Japan); Komatsu, Kenshi [Department of Genome Dynamics, Radiation Biology Center, Kyoto University, Kyoto 606-8501 (Japan); Matsuura, Shinya [Department of Radiation Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553 (Japan)], E-mail: shinya@hiroshima-u.ac.jp

2007-11-03T23:59:59.000Z

239

Star Formation and Chemical Evolution of Lyman-Break Galaxies  

E-Print Network (OSTI)

The number density and clustering properties of Lyman-break galaxies (LBGs)observed at redshift $z\\sim 3$ are best explained by assuming that they areassociated with the most massive haloes at $z\\sim 3$ predicted in hierarchicalmodels of structure formation. In this paper we study, under the sameassumption, how star formation and chemical enrichment may have proceeded inthe LBG population. A consistent model, in which the amount of cold gasavailable for star formation must be regulated, is suggested. It is found thatgas cooling in dark haloes provides a natural regulation process. In thismodel, the star formation rate in an LBG host halo is roughly constant overabout 1 Gyr. The predicted star formation rates and effective radii areconsistent with observations. The metallicity of the gas associated with an LBGis roughly equal to the chemical yield, or about the order of $1 Z_{\\odot}$ fora Salpeter IMF. The contribution to the total metals of LBGs is roughlyconsistent with that obtained from the observed cosmic...

Shu, C

2000-01-01T23:59:59.000Z

240

Star Formation and Chemical Evolution of Lyman-Break Galaxies  

E-Print Network (OSTI)

The number density and clustering properties of Lyman-break galaxies (LBGs) observed at redshift $z\\sim 3$ are best explained by assuming that they are associated with the most massive haloes at $z\\sim 3$ predicted in hierarchical models of structure formation. In this paper we study, under the same assumption, how star formation and chemical enrichment may have proceeded in the LBG population. A consistent model, in which the amount of cold gas available for star formation must be regulated, is suggested. It is found that gas cooling in dark haloes provides a natural regulation process. In this model, the star formation rate in an LBG host halo is roughly constant over about 1 Gyr. The predicted star formation rates and effective radii are consistent with observations. The metallicity of the gas associated with an LBG is roughly equal to the chemical yield, or about the order of $1 Z_{\\odot}$ for a Salpeter IMF. The contribution to the total metals of LBGs is roughly consistent with that obtained from the observed cosmic star formation history. The model predicts a marked radial metallicity gradient in a galaxy, with the gas in the outer region having much lower metallicity. As a result, the metallicities for the damped Lyman-alpha absorption systems expected from the LBG population are low. Since LBG halos are filled with hot gas in this model, their contributions to the soft X-ray background and to the UV ionization background are calculated and discussed.

Chenggang Shu

2000-02-21T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Superior refining performance beyond 2000 -- Breaking traditional paradigms  

SciTech Connect

Over the last 5 years, refining companies have not performed well financially, generating returns below the cost of capital. Environmental regulations have caused the industry to invest significant amounts of capital, and while new regulations will cause the shutdown of between 500 thousand and 1.2 million barrels per day of capacity, the industry structure will remain poor and financial returns for the average player will likely be volatile, cyclical, and below the cost of capital. Based on this industry outlook, refining companies seeking superior performance will have to break the traditional paradigms and adopt world-class practices used in other industries. Changes required to significantly improve financial returns will include shifts in business strategy to accommodate growth, and development of nontraditional services, as well as initiates to dramatically reshape cost structure and improve profitability. Making the changes to become a superior performer in the refining business will require a clear vision and strong leadership at multiple levels in the organization. The transformation will also require changes in company culture and incentive plans that encourage managers to act as owners. In addition, superior performers will push accountability for results to low levels in the organization. Given the herd mentality of the oil industry, superior performers must take decisive, preemptive action to generate a substantial, competitive advantage.

Tassel, B. van [McKinsey and Co., Inc., Houston, TX (United States)

1995-09-01T23:59:59.000Z

242

ULTRASONIC DETECTION OF SURFACE-BREAKING RAILHEAD DEFECTS  

Science Conference Proceedings (OSTI)

We recently presented measurements of defects on the railhead, using a novel pitch-catch ultrasonic system comprising of two electro-magnetic acoustic transducers (EMATs) generating and detecting Rayleigh waves. Current systems used on the UK rail network for detecting surface breaking defects are limited in speed (5 mm). The non-contact EMAT system has the potential to operate at higher line speed, improving network inspection coverage. The current system detects signals and performs an FFT in less than 1 ms, and changes in the detected signal amplitude and frequency content are used to characterise defects. A new set of simulated defects on sections of rail have been produced, including half-face slots machined normal to the railhead surface, clusters of angled slots, and pocket defects more typical of real defects. The smallest pocket defects are difficult to detect, with changes in signal amplitude and cut-off falling close to the noise level. However, at chosen higher frequencies a drop in FFT magnitude indicates the presence of a defect, and this indicator can be logically combined with amplitude and cut-off measurements to provide a more reliable result. Preparation for testing on a rotating rail rig at high speeds is ongoing.

Edwards, R. S.; Fan, Y.; Dixon, S. [University of Warwick, Department of Physics, Coventry CV4 7AL (United Kingdom); Papaelias, M.; Davis, C. L.; Roberts, C. [University of Birmingham, School of Engineering, Birmingham (United Kingdom)

2008-02-28T23:59:59.000Z

243

Treatment methods for breaking certain oil and water emulsions  

DOE Patents (OSTI)

Disclosed are treatment methods for breaking emulsions of petroleum oil and salt water, fatty oil and water, and those resulting from liquefication of organic material. The emulsions are broken by heating to a predetermined temperature at or above about 200.degree. C. and pressurizing to a predetermined pressure above the vapor pressure of water at the predetermined temperature to produce a heated and pressurized fluid. The heated and pressurized fluid is contained in a single vessel at the predetermined temperature and pressure for a predetermined period of time to effectively separate the emulsion into substantially distinct first and second phases, the first phase comprising primarily the petroleum oil, the second phase comprising primarily the water. The first and second phases are separately withdrawn from the vessel at a withdraw temperature between about 200.degree. C. and 374.degree. C. and a withdraw pressure above the vapor pressure of water at the withdraw temperature. Where solids are present in the certain emulsions, the above described treatment may also effectively separate the certain emulsion into a substantially distinct third phase comprising primarily the solids.

Sealock, Jr., L. John (W. Richland, WA); Baker, Eddie G. (Richland, WA); Elliott, Douglas C. (Richland, WA)

1992-01-01T23:59:59.000Z

244

Higgs boson mass bounds separate models of electroweak symmetry breaking  

SciTech Connect

Vacuum stability and metastability imply lower limits on the mass of the Higgs boson in the standard model (SM). In contrast, we present an improved calculation of the lightest Higgs boson mass in supersymmetric (SUSY) models, by summing to all orders in perturbation theory the leading and next-to-leading logarithms with a renormalization group equation technique, and by including finite two-loop QCD corrections. We believe our result to be the most accurate available in the literature. The mass calculation leads to an upper bound on the Higgs boson mass when the SUSY-breaking scale is sensibly restricted to {approx_lt}1 TeV. In particular, our improvements to the SUSY Higgs boson mass calculation lower the minimal SUSY standard model (MSSM) upper limit by about 10 GeV. We study the possibility that these SM and MSSM bounds do not overlap, in which case a single Higgs boson mass measurement will distinguish between the two models. (Abstract Truncated)

Diaz, M.A. [Physics Department, University of Southampton, Southampton, SO17 1BJ (United Kingdom); ter Veldhuis, T.A.; Weiler, T.J. [Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235 (United States)

1996-11-01T23:59:59.000Z

245

DNA | Open Energy Information  

Open Energy Info (EERE)

DNA DNA Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home NEPA Casual Use Determination of NEPA Adequacy Categorical Exclusion Environmental Assessment Environmental Impact Statements Print PDF NEPA-Related Analysis: Determination of NEPA Adequacy (DNA) General Document Collections (28) Documents Regulatory Roadmap NEPA-Related Analysis: Determination of NEPA Adequacy and Land Use Plan Conformance (DNA) placeholder. This query has been included to allow you to use the black arrows in the table header cells to sort the table data. Document # Serial Number Applicant Lead Agency District Office Field Office Development Phase(s) Techniques DOI-BLM-NM-L000-2012-0020-DNA Lightning Dock Geothermal Inc BLM BLM Las Cruces District Office BLM Geothermal/Exploration

246

Endogenous DNA Damage and Risk of Testicular Germ Cell Tumors  

SciTech Connect

Testicular germ cell tumors (TGCT) are comprised of two histologic groups, seminomas and nonseminomas. We postulated that the possible divergent pathogeneses of these histologies may be partially explained by variable endogenous DNA damage. To assess our hypothesis, we conducted a case-case analysis of seminomas and nonseminomas using the alkaline comet assay to quantify single-strand DNA breaks and alkali-labile sites. The Familial Testicular Cancer study and the U.S. Radiologic Technologists cohort provided 112 TGCT cases (51 seminomas & 61 nonseminomas). A lymphoblastoid cell line was cultured for each patient and the alkaline comet assay was used to determine four parameters: tail DNA, tail length, comet distributed moment (CDM) and Olive tail moment (OTM). Odds ratios (OR) and 95% confidence intervals (95%CI) were estimated using logistic regression. Values for tail length, tail DNA, CDM and OTM were modeled as categorical variables using the 50th and 75th percentiles of the seminoma group. Tail DNA was significantly associated with nonseminoma compared to seminoma (OR{sub 50th percentile} = 3.31, 95%CI: 1.00, 10.98; OR{sub 75th percentile} = 3.71, 95%CI: 1.04, 13.20; p for trend=0.039). OTM exhibited similar, albeit statistically non-significant, risk estimates (OR{sub 50th percentile} = 2.27, 95%CI: 0.75, 6.87; OR{sub 75th percentile} = 2.40, 95%CI: 0.75, 7.71; p for trend=0.12) whereas tail length and CDM showed no association. In conclusion, the results for tail DNA and OTM indicate that endogenous DNA damage levels are higher in patients who develop nonseminoma compared with seminoma. This may partly explain the more aggressive biology and younger age-of-onset of this histologic subgroup compared with the relatively less aggressive, later-onset seminoma.

Cook, M B; Sigurdson, A J; Jones, I M; Thomas, C B; Graubard, B I; Korde, L; Greene, M H; McGlynn, K A

2008-01-18T23:59:59.000Z

247

Impact of Breaking Wave Form Drag on Near-Surface Turbulence and Drag Coefficient over Young Seas at High Winds  

Science Conference Proceedings (OSTI)

The effects of breaking waves on near-surface wind turbulence and drag coefficient are investigated using large-eddy simulation. The impact of intermittent and transient wave breaking events (over a range of scales) is modeled as localized form ...

Nobuhiro Suzuki; Tetsu Hara; Peter P. Sullivan

2013-02-01T23:59:59.000Z

248

Design Considerations for Monopile Founded Offshore Wind Turbines Subject to Breaking Waves  

E-Print Network (OSTI)

The majority of offshore wind farms utilize monopile substructures. As these wind farms are typically located in water depths less than 30 meters, the effect of breaking waves on these structures is of great concern to design engineers. This research investigation examines many of the practical considerations and alternative ways of estimating breaking wave forces. A survey of existing European wind farms is used to establish a realistic range of basic design parameters. Based upon this information a parametric study was pursued and a series of realistic design scenarios were evaluated. Comparisons include the sensitivity to the wave force model as well as to analytical and numerical wave theories used to evaluate the wave kinematics. In addition, the effect of different kinematics stretching techniques for linear waves is addressed. Establishing whether the bathymetry will induce spilling or plunging wave breaking is critical. Spilling wave breaking can be addressed using existing wave and wave force theories; however for plunging wave breaking an additional impact force must be introduced. Dimensionless design curves are used to display pertinent trends across the full range of design cases considered. This research study provides insight into the evaluation of the maximum breaking wave forces and overturning moment for both spilling and plunging breaking waves as a function of bottom slope.

Owens, Garrett 1987-

2012-12-01T23:59:59.000Z

249

Particle-Hole Symmetry Breaking in the Pseudogap State of Bi2201  

Science Conference Proceedings (OSTI)

In conventional superconductors, a gap exists in the energy absorption spectrum only below the transition temperature (T{sub c}), corresponding to the energy price to pay for breaking a Cooper pair of electrons. In high-T{sub c} cuprate superconductors above T{sub c}, an energy gap called the pseudogap exists, and is controversially attributed either to pre-formed superconducting pairs, which would exhibit particle-hole symmetry, or to competing phases which would typically break it. Scanning tunnelling microscopy (STM) studies suggest that the pseudogap stems from lattice translational symmetry breaking and is associated with a different characteristic spectrum for adding or removing electrons (particle-hole asymmetry). However, no signature of either spatial or energy symmetry breaking of the pseudogap has previously been observed by angle-resolved photoemission spectroscopy (ARPES). Here we report ARPES data from Bi2201 which reveals both particle-hole symmetry breaking and dramatic spectral broadening indicative of spatial symmetry breaking without long range order, upon crossing through T* into the pseudogap state. This symmetry breaking is found in the dominant region of the momentum space for the pseudogap, around the so-called anti-node near the Brillouin zone boundary. Our finding supports the STM conclusion that the pseudogap state is a broken-symmetry state that is distinct from homogeneous superconductivity.

Hashimoto, M.; /SIMES, Stanford /Stanford U., Geballe Lab. /LBNL, ALS; He, R.-H.; /aff SIMES, Stanford /Stanford U., Geballe Lab.; Tanaka, K.; /aff SIMES, Stanford /Stanford U., Geballe Lab. /LBNL, ALS /Osaka U.; Testaud, J.P.; /SIMES, Stanford /Stanford U., Geballe Lab. /LBNL, ALS; Meevasana1, W.; Moore, R.G.; Lu, D.H.; /SIMES, Stanford /Stanford U., Geballe Lab.; Yao, H.; /SIMES, Stanford; Yoshida, Y.; Eisaki, H.; /AIST, Tsukuba; Devereaux, T.P.; /SIMES, Stanford /Stanford U., Geballe Lab.; Hussain, Z.; /LBNL, ALS; Shen, Z.-X.; /SIMES, Stanford /Stanford U., Geballe Lab.

2011-08-19T23:59:59.000Z

250

Quantitive DNA Fiber Mapping  

SciTech Connect

Several hybridization-based methods used to delineate single copy or repeated DNA sequences in larger genomic intervals take advantage of the increased resolution and sensitivity of free chromatin, i.e., chromatin released from interphase cell nuclei. Quantitative DNA fiber mapping (QDFM) differs from the majority of these methods in that it applies FISH to purified, clonal DNA molecules which have been bound with at least one end to a solid substrate. The DNA molecules are then stretched by the action of a receding meniscus at the water-air interface resulting in DNA molecules stretched homogeneously to about 2.3 kb/{micro}m. When non-isotopically, multicolor-labeled probes are hybridized to these stretched DNA fibers, their respective binding sites are visualized in the fluorescence microscope, their relative distance can be measured and converted into kilobase pairs (kb). The QDFM technique has found useful applications ranging from the detection and delineation of deletions or overlap between linked clones to the construction of high-resolution physical maps to studies of stalled DNA replication and transcription.

Lu, Chun-Mei; Wang, Mei; Greulich-Bode, Karin M.; Weier, Jingly F.; Weier, Heinz-Ulli G.

2008-01-28T23:59:59.000Z

251

Making and breaking of water in crude oil emulsions  

E-Print Network (OSTI)

An understanding of the processes involved in oil spills, and how they interact to alter the composition and behavior of the oil with respect to time is essential to determine an effective oil spill response. The review of past research has shown more focus on the laboratory methods and computerized modeling schemes to estimate the formation and breaking of emulsions after an oil spill. However, relatively less effort has gone into the study of emulsions corresponding to actual field conditions. This research aims to simulate an oil spill at sea by developing a new technique to make water in oil emulsions, without disturbing the marine wildlife. Further, this research also attempts to analyze the viscosities of water in oil emulsions and determine appropriate emulsion breakers for different crude oil emulsions. The overall test design for the study includes a test apparatus for spreading and evaporation, three different crude oils, a mixing chamber to form the emulsion, and emulsion breakers. Experiments in this research attempt to gain a better understanding of the processes that occur after oil spills at sea. In particular, the rate of evaporation of different crude oils and the formation of crude oil emulsions on the sea surface have been investigated. It was observed that different crude oils behave differently when subjected to the same weathering procedure. Results indicate that the behavior of the crude oil on the sea surface, subjected to spreading, evaporation, and emulsification, can be predicted by using the new technique developed in this research. This technique can also assist the development of effective recovery equipments and materials.

Mehta, Shweta D.

2005-12-01T23:59:59.000Z

252

Determining the angles of break of the mining subsidence basin by the neural network with genetic algorithm  

Science Conference Proceedings (OSTI)

The angle of break is a key factor that determines the mining damage extent of the surface in a mine, and it is also used to depict the characteristics of the mining subsidence basin. The geological and mining factors that influence the angle of break ... Keywords: angle of break, genetic algorithm, neural network, subsidence basin

Hua-bin Chai

2010-03-01T23:59:59.000Z

253

Break-up of Pt catalyst surfaces by high CO coverage  

E-Print Network (OSTI)

and atomic arrangement of catalyst surface under reactionof reactant molecules on the catalyst surfaces are the norm.Break-up of Pt catalyst surfaces by high CO coverage Feng

Tao, Feng

2010-01-01T23:59:59.000Z

254

Breaking of Progressive Internal Gravity Waves: Convective Instability and Shear Instability  

Science Conference Proceedings (OSTI)

The breaking of a monochromatic two-dimensional internal gravity wave is studied using a newly developed spectral/pseudospectral model. The model features vertical nonperiodic boundary conditions that ensure a realistic simulation of wave ...

Wei Liu; Francis P. Bretherton; Zhengyu Liu; Leslie Smith; Hao Lu; Christopher J. Rutland

2010-10-01T23:59:59.000Z

255

Breaking Up - And Making Up - Are Hard To Do | U.S. DOE Office of  

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

Breaking Up Breaking Up - And Making Up - Are Hard To Do News Featured Articles 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Presentations & Testimony News Archives Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 12.27.11 Breaking Up - And Making Up - Are Hard To Do But as Office of Science research shows, the results can be electric. Print Text Size: A A A Subscribe FeedbackShare Page It's said that breaking up is hard to do. That's undoubtedly true. And so is making up, as more than a few forlorn hearts have found. But when the lightning does strike, the electricity is lasting. What's true for the affairs of the heart also holds for the affairs of hydrogen, as researchers at the Office of Science's Argonne National

256

Breaks in presence in virtual environments: An analysis of blood flow velocity responses  

Science Conference Proceedings (OSTI)

One of the techniques used to monitor variations in presence during a virtual reality experience is the analysis of breaks in presence (BIPs). Previous studies have monitored peripheral physiological responses during BIPs in order to find a characteristic ...

Beatriz Rey; Vera Parkhutik; Mariano Alcañiz

2011-06-01T23:59:59.000Z

257

Introduction of Break-Out Session at the International PV Module Quality Assurance Forum (Presentation)  

DOE Green Energy (OSTI)

This presentation outlines review requirements for quality assurance (QA) rating systems, logical design of QA systems, and specific tasks for break-out session 1 of the 2011 International PV Module Quality Assurance Forum.

Kurtz, S.; Wohlgemuth, J.; Yamamichi, M.; Sample, T.

2011-07-01T23:59:59.000Z

258

Physics and learning based computational models for breaking bow waves based on new boundary immersion approaches  

E-Print Network (OSTI)

A ship moving on the free surface produces energetic breaking bow waves which generate spray and air entrainment. Present experimental, analytic, and numerical studies of this problem are costly, inaccurate and not robust. ...

Weymouth, Gabriel David

2008-01-01T23:59:59.000Z

259

Simulation of Inertia–Gravity Waves in a Poleward-Breaking Rossby Wave  

Science Conference Proceedings (OSTI)

Poleward-breaking Rossby waves often induce an upper-level jet streak over northern Europe. Dominant inertia–gravity wave packets are observed downstream of this jet. The physical processes of their generation and propagation, in such a ...

Christoph Zülicke; Dieter Peters

2006-12-01T23:59:59.000Z

260

Spectrally Resolved Energy Dissipation Rate and Momentum Flux of Breaking Waves  

Science Conference Proceedings (OSTI)

Video observations of the ocean surface taken from aboard the Research Platform FLIP reveal the distribution of the along-crest length and propagation velocity of breaking wave crests that generate visible whitecaps. The key quantity assessed is ...

Johannes R. Gemmrich; Michael L. Banner; Chris Garrett

2008-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

The Nature of the Far-UV Break in the Energy Distribution of Quasars  

E-Print Network (OSTI)

A prominent continuum steepening is observed in quasar energy distributions near 1100A. We review possible interpretations for the physical origin of this so-called far-UV break.

L. Binette; S. Haro-Corzo; Y. Krongold; A. C. Andersen

2007-06-13T23:59:59.000Z

262

Rossby Wave Breaking and Transport between the Tropics and Extratropics above the Subtropical Jet  

Science Conference Proceedings (OSTI)

Rossby wave breaking is an important mechanism for the two-way exchange of air between the tropical upper troposphere and lower stratosphere and the extratropical lower stratosphere. The authors present a 30-yr climatology (1981–2010) of ...

Cameron R. Homeyer; Kenneth P. Bowman

2013-02-01T23:59:59.000Z

263

Impact of Rossby wave breaking on U.S. west coast winter precipitation during ENSO events  

Science Conference Proceedings (OSTI)

This study demonstrates that water vapor transport and precipitation are largely modulated by the intensity of the subtropical jet, transient eddies, and the location of wave breaking events during the different phases of ENSO. Clear differences ...

Ju-Mee Ryoo; Yohai Kaspi; Darryn W. Waugh; George N. Kiladis; Duane E. Waliser; Eric J. Fetzer; Jinwon Kim

264

About Spontaneous Symmetry Breaking in the Field Theory with Fundamental Mass  

E-Print Network (OSTI)

The simple examples of spontaneous breaking of various symmetries for the scalar theory with fundamental mass have been considered. Higgs generalizations on "fundamental mass" were introduced into the theory on a basis of the five-dimensional de Sitter space.

Umida Khodjaeva

2006-02-28T23:59:59.000Z

265

TRAC large-break loss-of-coolant accident analysis for the AP600 design  

Science Conference Proceedings (OSTI)

This report discusses a TRAC model of the Westinghouse AP600 advanced reactor design which has been developed for analyzing large-break loss-of-coolant accident (LBLOCA) transients. A preliminary LBLOCA calculation of a 80% cold-leg break has been performed with TRAC-PF1/MOD2. The 80% break size was calculated by Westinghouse to be the most severe large-break size. The LBLOCA transient was calculated to 92 s. Peak clad temperatures (PCT) were well below the Appendix K limit of 1478 K (2200{degrees}F). Transient event times and PCT for the TRAC calculation were in reasonable agreement with those calculated by Westinghouse using their WCOBRA/TRAC code.

Lime, J.F.; Boyack, B.E.

1994-02-01T23:59:59.000Z

266

Breaking Surface Wave Effects on River Plume Dynamics during Upwelling-Favorable Winds  

Science Conference Proceedings (OSTI)

This study examines the dynamics of a buoyant river plume in upwelling favorable winds, concentrating on the time after separation from the coast. A set of idealized numerical simulations is used to examine the effects of breaking surface gravity ...

Gregory P. Gerbi; Robert J. Chant; John L. Wilkin

267

Statistics of Breaking Waves Observed as Whitecaps in the Open Sea  

Science Conference Proceedings (OSTI)

Conventional observations of waves carried out with a buoy in open sea conditions were supplemented with simultaneous visual observations of whitecaps to identify breaking events in the buoy records. A statistical wave-by-wave analysis of these ...

L. H. Holthuijsen; T. H. C. Herbers

1986-02-01T23:59:59.000Z

268

Observation of an Anticyclonic Eddy near the Continental Shelf Break South of New England  

Science Conference Proceedings (OSTI)

A small scale but energetic and highly nonlinear anticyclonic eddy was observed near the New England Shelf Break in July 1983. Satellite images show a tongue of shelf water 15 km wide flowing offshore then turning anticyclonically westward. ...

Robert W. Houghton; Donald B. Olson; Peter J. Celone

1986-01-01T23:59:59.000Z

269

A Seasonal Climatology of Rossby Wave Breaking in the 320–2000-K Layer  

Science Conference Proceedings (OSTI)

Differential advection in Rossby waves can lead to potential vorticity (PV; P) contours on isentropic surfaces folding over in latitude (Py < 0) in a process called Rossby wave breaking (RWB). Exploring the properties of RWB may shed light on ...

Matthew H. Hitchman; Amihan S. Huesmann

2007-06-01T23:59:59.000Z

270

A Spectral Parameterization of Mean-Flow Forcing due to Breaking Gravity Waves  

Science Conference Proceedings (OSTI)

A spectral parameterization of mean-flow forcing due to breaking gravity waves is described for application in the equations of motion in atmospheric models. The parameterization is based on linear theory and adheres closely to fundamental ...

M. J. Alexander; T. J. Dunkerton

1999-12-01T23:59:59.000Z

271

A Fourier-Based Method for the Distribution of Breaking Crests from Video Observations  

Science Conference Proceedings (OSTI)

A Fourier-based method is presented to process video observations of water waves and calculate the speed distribution of breaking crest lengths. The method has increased efficiency and robust statistics compared with conventional algorithms that ...

Jim Thomson; Andrew T. Jessup

2009-08-01T23:59:59.000Z

272

Breaking Surface Wave Effects on River Plume Dynamics during Upwelling-Favorable Winds  

Science Conference Proceedings (OSTI)

This study examines the dynamics of a buoyant river plume in upwelling-favorable winds, concentrating on the time after separation from the coast. A set of idealized numerical simulations is used to examine the effects of breaking surface gravity ...

Gregory P. Gerbi; Robert J. Chant; John L. Wilkin

2013-09-01T23:59:59.000Z

273

Supersymmetry Breaks Itself for Quarks and Leptons in the SUSY Standard Model  

E-Print Network (OSTI)

Models like the Supersymmetric Standard Model (SSM) possess simple, but well-hidden, `Outfields'. These Outfields are composite operators that violate superspace invariance, but in a special way. A new mechanism for SUSY breaking arises from the Outfields, for a special non-minimal version of the SSM, which will be called the CSSM. The CSSM has right neutrinos and a Higgs singlet, which we call J, in addition to the usual SSM. This breaking of SUSY cannot be avoided, because it arises from the local BRST cohomology of the theory, which is also the origin of the Outfields. It can also be seen that the Weak SU(2) group, and the well-known remarkable set of doublets and singlets for the Quarks, Leptons and Higgs, have a raison d'etre which relates to this mechanism. The SUSY breaking here depends on only one parameter, which is the VEV that breaks SU(2) X U(1) to U(1). SUSY itself is not spontaneously broken here, so the vacuum energy remains zero after SUSY breaking. The resulting predictions for SUSY breaking are very constrained by the model.

John A. Dixon

2010-12-21T23:59:59.000Z

274

DNA polymerase having modified nucleotide binding site for DNA sequencing  

DOE Patents (OSTI)

A modified gene encoding a modified DNA polymerase is disclosed. The modified polymerase incorporates dideoxynucleotides at least 20-fold better compared to the corresponding deoxynucleotides as compared with the corresponding naturally-occurring DNA polymerase. 6 figs.

Tabor, S.; Richardson, C.

1997-03-25T23:59:59.000Z

275

Searching for DNA Lesions: Structural Evidence for Lower- and Higher-Affinity DNA Binding Conformations of Human Alkyladenine DNA Glycosylase  

E-Print Network (OSTI)

To efficiently repair DNA, human alkyladenine DNA glycosylase (AAG) must search the million-fold excess of unmodified DNA bases to find a handful of DNA lesions. Such a search can be facilitated by the ability of glycosylases, ...

Drennan, Catherine L.

276

Generating DNA code word for DNA computing with realtime PCR  

Science Conference Proceedings (OSTI)

A number of DNA computing models to solve mathematical graph problem such as the Hamiltonian Path Problem (HPP), Traveling Salesman Problem (TSP), and the Shortest Path Problem (SPP) have been proposed and demonstrated. Normally, the DNA sequences used ... Keywords: DNA computing, TaqMan probes, real-time PCR

Muhammad Faiz Mohamed Saaid; Zuwairie Ibrahim; Nor Haniza Sarmin

2008-03-01T23:59:59.000Z

277

Natural DNA sequencing by synthesis  

E-Print Network (OSTI)

high throughput genome sequencing by natural DNA synthesis.E.E. , et al. , Genome sequencing by natural DNA synthesis.p. 1304-51. Human Genome Sequencing, C.I. , Finishing the

Roller, Eric E.

2011-01-01T23:59:59.000Z

278

DNA Profiling Standard Reference Materials  

Science Conference Proceedings (OSTI)

... agreement with the NIST Office of Law Enforcement Standards. ... Related Programs and Projects: SRM 2372 - Human DNA Quantitation Standard. ...

2013-03-15T23:59:59.000Z

279

DuPont Technology Breaks Away From Glass | Department of Energy  

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

DuPont Technology Breaks Away From Glass DuPont Technology Breaks Away From Glass DuPont Technology Breaks Away From Glass April 22, 2010 - 4:20pm Addthis Delaware-based DuPont is working to develop ultra-thin moisture protective films for photovoltaic panels - so thin they're about 1,000 times thinner than a human hair. DuPont is working on new photovoltaic technology that will let manufacturers of copper indium gallium selenide, or CIGS, solar cells and organic light emitting diodes, or OLED, displays protect products with thin layers of ceramic and polymer material instead of glass. These ultra-thin protective films could help prevent deterioration from moisture. Because of their potential to reduce the cost of producing solar energy, "thin-film PV modules are projected to be the fastest-growing segment of

280

Breaking Down Enzymes' Role in Biofuel Production | U.S. DOE Office of  

Office of Science (SC) Website

Breaking Down Enzymes' Role in Biofuel Production Breaking Down Enzymes' Role in Biofuel Production Biological and Environmental Research (BER) BER Home About Research Facilities Science Highlights Searchable Archive of BER Highlights External link Benefits of BER Funding Opportunities Biological & Environmental Research Advisory Committee (BERAC) News & Resources Contact Information Biological and Environmental Research U.S. Department of Energy SC-23/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3251 F: (301) 903-5051 E: sc.ber@science.doe.gov More Information » February 2013 Breaking Down Enzymes' Role in Biofuel Production Molecular structures provide insights into biomass deconstruction. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Record-breaking year for patents | Y-12 National Security Complex  

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

Record-breaking year for ... Record-breaking year for ... Record-breaking year for patents Posted: February 11, 2013 - 2:57pm | Y-12 Report | Volume 9, Issue 2 | 2013 Fiscal 2012 was a fruitful year for innovative research and development at the Y-12 National Security Complex. Site inventors were issued an unprecedented 11 patents. Technologies and processes from many of Y-12's latest patents, like those from previous years, can extend beyond the Nuclear Security Enterprise into diverse areas of private industry. One technology, the measurement system Extrans, determines how much water permeates a material. At Y-12 this measuring method can protect moisture-sensitive material from corroding. In the food or pharmaceutical industry, however, Extrans could test product packaging to ensure that no

282

Breaking a Cycle-Free Lifestyle for Earth Day | Department of Energy  

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

Breaking a Cycle-Free Lifestyle for Earth Day Breaking a Cycle-Free Lifestyle for Earth Day Breaking a Cycle-Free Lifestyle for Earth Day April 12, 2012 - 12:07pm Addthis Elizabeth Spencer Communicator, National Renewable Energy Laboratory Earth Day is just around the corner! And while it might not be a major day for most people, I still think it's kind of fun. I think every special day is an excuse to do something you normally wouldn't! (And, speaking of little somethings, the Energy Efficiency and Renewable Energy website is going to have a small page up to commemorate Earth Day this year. Look for that next week.) This Earth Day, I'm buying a new bicycle! Now, before I start, let me get this out of the way: Bikes and I have not historically gotten along. When I was a young girl, I was so thrilled to

283

Breaking a Cycle-Free Lifestyle for Earth Day | Department of Energy  

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

Breaking a Cycle-Free Lifestyle for Earth Day Breaking a Cycle-Free Lifestyle for Earth Day Breaking a Cycle-Free Lifestyle for Earth Day April 12, 2012 - 12:07pm Addthis Elizabeth Spencer Communicator, National Renewable Energy Laboratory Earth Day is just around the corner! And while it might not be a major day for most people, I still think it's kind of fun. I think every special day is an excuse to do something you normally wouldn't! (And, speaking of little somethings, the Energy Efficiency and Renewable Energy website is going to have a small page up to commemorate Earth Day this year. Look for that next week.) This Earth Day, I'm buying a new bicycle! Now, before I start, let me get this out of the way: Bikes and I have not historically gotten along. When I was a young girl, I was so thrilled to

284

DuPont Technology Breaks Away From Glass | Department of Energy  

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

DuPont Technology Breaks Away From Glass DuPont Technology Breaks Away From Glass DuPont Technology Breaks Away From Glass April 22, 2010 - 4:20pm Addthis Delaware-based DuPont is working to develop ultra-thin moisture protective films for photovoltaic panels - so thin they're about 1,000 times thinner than a human hair. DuPont is working on new photovoltaic technology that will let manufacturers of copper indium gallium selenide, or CIGS, solar cells and organic light emitting diodes, or OLED, displays protect products with thin layers of ceramic and polymer material instead of glass. These ultra-thin protective films could help prevent deterioration from moisture. Because of their potential to reduce the cost of producing solar energy, "thin-film PV modules are projected to be the fastest-growing segment of

285

Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Facility |  

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

Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Facility Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Facility August 13, 2013 - 10:54am Addthis News Media Contact (202) 586-4940 WASHINGTON - Building on President Obama's Climate Action Plan, which calls for steady, responsible steps to reduce carbon pollution, the Energy Department today broke ground on the nation's largest federally-owned wind project at the Pantex Plant in Amarillo, Texas. Once completed, this five-turbine 11.5 megawatt project will power more than 60 percent of the plant with clean, renewable wind energy and reduce carbon emissions by over 35,000 metric tons per year - equivalent to taking 7,200 cars off the road. The Pantex Plant is the primary site for the assembly, disassembly,

286

Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Facility |  

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

Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Facility Largest Federally-Owned Wind Farm Breaks Ground at U.S. Weapons Facility August 13, 2013 - 10:54am Addthis News Media Contact (202) 586-4940 WASHINGTON - Building on President Obama's Climate Action Plan, which calls for steady, responsible steps to reduce carbon pollution, the Energy Department today broke ground on the nation's largest federally-owned wind project at the Pantex Plant in Amarillo, Texas. Once completed, this five-turbine 11.5 megawatt project will power more than 60 percent of the plant with clean, renewable wind energy and reduce carbon emissions by over 35,000 metric tons per year - equivalent to taking 7,200 cars off the road. The Pantex Plant is the primary site for the assembly, disassembly,

287

Breaking Up (Hydrogen) No Longer As Hard To Do | Department of Energy  

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

Breaking Up (Hydrogen) No Longer As Hard To Do Breaking Up (Hydrogen) No Longer As Hard To Do Breaking Up (Hydrogen) No Longer As Hard To Do December 29, 2011 - 1:12pm Addthis Researchers at Argonne National Lab have recently developed a process to improve the efficiency of producing hydrogen to run cars such as this prototype, which was developed at the Oakridge National Lab. | Photo courtesy of Oak Ridge National Laboratory. Researchers at Argonne National Lab have recently developed a process to improve the efficiency of producing hydrogen to run cars such as this prototype, which was developed at the Oakridge National Lab. | Photo courtesy of Oak Ridge National Laboratory. Charles Rousseaux Charles Rousseaux Senior Writer, Office of Science What does this project do? Researchers have new insight into producing pure hydrogen -- a

288

Breaking Up (Hydrogen) No Longer As Hard To Do | Department of Energy  

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

Breaking Up (Hydrogen) No Longer As Hard To Do Breaking Up (Hydrogen) No Longer As Hard To Do Breaking Up (Hydrogen) No Longer As Hard To Do December 29, 2011 - 1:12pm Addthis Researchers at Argonne National Lab have recently developed a process to improve the efficiency of producing hydrogen to run cars such as this prototype, which was developed at the Oakridge National Lab. | Photo courtesy of Oak Ridge National Laboratory. Researchers at Argonne National Lab have recently developed a process to improve the efficiency of producing hydrogen to run cars such as this prototype, which was developed at the Oakridge National Lab. | Photo courtesy of Oak Ridge National Laboratory. Charles Rousseaux Charles Rousseaux Senior Writer, Office of Science What does this project do? Researchers have new insight into producing pure hydrogen -- a

289

Nucleotide cleaving agents and method  

DOE Patents (OSTI)

The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.

Que, Jr., Lawrence (Roseville, MN); Hanson, Richard S. (Falcon Heights, MN); Schnaith, Leah M. T. (Redwing, MN)

2000-01-01T23:59:59.000Z

290

In silico analysis of mycobacteriophage Che12 genome: Characterization of genes required to lysogenise Mycobacterium tuberculosis  

Science Conference Proceedings (OSTI)

Che12 is a temperate Chennai phage infecting Mycobacterium tuberculosis. The nucleotide sequence of the 52,047bp linear double stranded DNA genome has a GC content of 62.9% with 70 putative ORFs identified. Functions are assigned to 24 genes based on ... Keywords: Bioinformatics, Mycobacterium tuberculosis, Temperate mycobacteriophage

N. S. Gomathi; H. Sameer; Vanaja Kumar; S. Balaji; V.N. Azger Dustackeer; P. R. Narayanan

2007-04-01T23:59:59.000Z

291

Uncertainty in Electroweak Symmetry Breaking in Models With High Scale Supersymmetry Breaking and its Impact on Interpretations of Searches For Supersymmetric Particles  

E-Print Network (OSTI)

Some regions of parameter space of the minimal supersymmetric standard model (MSSM) with high scale supersymmetry breaking have extreme sensitivity of electroweak symmetry breaking (EWSB) to the top quark mass through renormalisation group evolution effects. This leads to uncertainties in the predictions which need to be taken into account in the interpretation of searches for supersymmetric particles in these regions. As an example, we provide estimates of the current uncertainties on the position in parameter space of the region which does not break electroweak symmetry in the constrained MSSM (CMSSM). The position of the boundary of EWSB can vary by up to 2 TeV in m_0 due to the uncertainties coming from the current measurement errors on the top quark mass and from higher order corrections. In this dangerous region, for fixed CMSSM parameters the neutralino lightest supersymmetric particle mass has an associated large uncertainty of order 100%. These uncertainties therefore have a profound effect on the interpretation of LHC supersymmetric particle searches in terms of the CMSSM. We also show how to ameliorate poor convergence of the iterative numerical algorithm that calculates the MSSM spectrum near the boundary of EWSB.

B. C. Allanach; M. A. Parker

2012-11-14T23:59:59.000Z

292

A molecular dynamics simulation of DNA damage induction by ionizing radiation  

E-Print Network (OSTI)

We present a multi-scale simulation of early stage of DNA damages by the indirect action of hydroxyl ($^\\bullet$OH) free radicals generated by electrons and protons. The computational method comprises of interfacing the Geant4-DNA Monte Carlo with the ReaxFF molecular dynamics software. A clustering method was employed to map the coordinates of $^\\bullet$OH-radicals extracted from the ionization track-structures onto nano-meter simulation voxels filled with DNA and water molecules. The molecular dynamics simulation provides the time evolution and chemical reactions in individual simulation voxels as well as the energy-landscape accounted for the DNA-$^\\bullet$OH chemical reaction that is essential for the first principle enumeration of hydrogen abstractions, chemical bond breaks, and DNA-lesions induced by collection of ions in clusters less than the critical dimension which is approximately 2-3 \\AA. We show that the formation of broken bonds leads to DNA base and backbone damages that collectively propagate ...

Abolfath, Ramin M; Chen, Zhe J; Nath, Ravinder

2013-01-01T23:59:59.000Z

293

Q, Break-even and the n{tau{sub E}} Diagram for Transient Fusion Plasmas  

SciTech Connect

Q, break-even and the Lawson diagram are well defined and understood for steady-state fusion plasma conditions. Since many fusion experiments are transient, it is necessary to clarify the definitions for instantaneous Q values and break-even so that the Lawson diagram can be interpreted for transient plasma conditions. This discussion shows that there are two mathematically correct methods to describe the Lawson diagram for a transient plasma: the Lawson/TFTR method and the JET/JT-60 method. These methods are discussed in detail in this paper.

Dale M. Meade

1998-04-01T23:59:59.000Z

294

Multicritical Symmetry Breaking and Naturalness of Slow Nambu-Goldstone Bosons  

E-Print Network (OSTI)

We investigate spontaneous global symmetry breaking in the absence of Lorentz invariance, and study technical Naturalness of Nambu-Goldstone (NG) modes whose dispersion relation exhibits a hierarchy of multicritical phenomena with Lifshitz scaling and dynamical exponents $z>1$. For example, we find NG modes with a technically natural quadratic dispersion relation which do not break time reversal symmetry and are associated with a single broken symmetry generator, not a pair. The mechanism is protected by an enhanced `polynomial shift' symmetry in the free-field limit.

Tom Griffin; Kevin T. Grosvenor; Petr Horava; Ziqi Yan

2013-08-27T23:59:59.000Z

295

From Decay to Complete Breaking: Pulling the Strings in SU(2) Yang-Mills Theory  

Science Conference Proceedings (OSTI)

We study (2Q+1) strings connecting two static charges Q in (2+1)D SU(2) Yang-Mills theory. While the fundamental (2) string between two charges Q=(1/2) is unbreakable, the adjoint (3) string connecting two charges Q=1 can break. When a (4) string is stretched beyond a critical length, it decays into a (2) string by gluon pair creation. When a (5) string is stretched, it first decays into a (3) string, which eventually breaks completely. The energy of the screened charges at the ends of a string is well described by a phenomenological constituent gluon model.

Pepe, M. [INFN, Istituto Nazionale di Fisica Nucleare, Sezione di Milano-Bicocca, Edificio U2, Piazza della Scienza 3, 20126 Milano (Italy); Wiese, U.-J. [Center for Research and Education in Fundamental Physics, Institute for Theoretical Physics, Bern University, Sidlerstrasse 5, 3012 Bern (Switzerland); Institute for Theoretical Physics, ETH Zuerich, Schafmattstrasse 32, CH-8093 Zuerich (Switzerland)

2009-05-15T23:59:59.000Z

296

Wave breaking phenomenon of lower-hybrid oscillations induced by a background inhomogeneous magnetic field  

Science Conference Proceedings (OSTI)

In a fluid description, we study space-time evolution of lower hybrid modes in a cold quasi-neutral homogeneous plasma in presence of a background inhomogeneous magnetic field. Within a linear analysis, a dispersion relation with inhomogeneous magnetic field shows 'phase mixing' of such oscillations. A manifestation of 'phase mixing' is shown in 'mode coupling.' By using Lagrangian variables, an exact solution is presented in parametric form of this nonlinear time dependent problem. It is demonstrated that initially excited lower hybrid modes always break via phase mixing phenomenon in presence of an inhomogeneous magnetic field. Breaking of such oscillations is revealed by the appearance of spikes in the plasma density profile.

Maity, Chandan; Chakrabarti, Nikhil [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Sengupta, Sudip [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2012-10-15T23:59:59.000Z

297

Evidence for layered symmetry breaking in SU(2) lattice gauge theory  

E-Print Network (OSTI)

Simulations of four-dimensional SU(2) lattice gauge theory are performed with partial axial gauge fixing trees spanning three of the four dimensions. The remaining SU(2) gauge symmetry, global in three directions and local in one, is found to break spontaneously at weak coupling, with the average fourth-dimension-pointing link in each perpendicular hyperplane as order parameter. The symmetry is restored at strong coupling. Symmetry breaking in each hyperplane appears to be independent, and occurs regardless of boundary conditions. The associated phase transition is likely coincident with the Polyakov loop transition.

Michael Grady

2004-09-29T23:59:59.000Z

298

The Messenger Sector of SUSY Flavour Models and Radiative Breaking of Flavour Universality  

E-Print Network (OSTI)

The flavour messenger sectors and their impact on the soft SUSY breaking terms are investigated in SUSY flavour models. In the case when the flavour scale M is below the SUSY breaking mediation scale M_S, the universality of soft terms, even if assumed at M_S, is radiatively broken. We estimate this effect in a broad class of models. In the CKM basis that effect gives flavour off-diagonal soft masses comparable to the tree-level estimate based on the flavour symmetry.

Calibbi, Lorenzo; Pokorski, Stefan; Ziegler, Robert

2012-01-01T23:59:59.000Z

299

Ultra-large distance modification of gravity from Lorentz symmetry breaking at the Planck scale  

E-Print Network (OSTI)

We present an extension of the Randall--Sundrum model in which, due to spontaneous Lorentz symmetry breaking, graviton mixes with bulk vector fields and becomes quasilocalized. The masses of KK modes comprising the four-dimensional graviton are naturally exponentially small. This allows to push the Lorentz breaking scale to as high as a few tenth of the Planck mass. The model does not contain ghosts or tachyons and does not exhibit the van Dam--Veltman--Zakharov discontinuity. The gravitational attraction between static point masses becomes gradually weaker with increasing of separation and gets replaced by repulsion (antigravity) at exponentially large distances.

D. S. Gorbunov; S. M. Sibiryakov

2005-06-08T23:59:59.000Z

300

Enhancement of the RAD51 Recombinase Activity by the Tumor Suppressor PALB2  

SciTech Connect

Homologous recombination mediated by the RAD51 recombinase helps eliminate chromosomal lesions, such as DNA double-stranded breaks induced by radiation or arising from injured DNA replication forks. The tumor suppressors BRCA2 and PALB2 act together to deliver RAD51 to chromosomal lesions to initiate repair. Here we document a new function of PALB2 in the enhancement of RAD51's ability to form the D-loop. We show that PALB2 binds DNA and physically interacts with RAD51. Importantly, while PALB2 alone stimulates D-loop formation, a cooperative effect is seen with RAD51AP1, an enhancer of RAD51. This stimulation stems from PALB2's ability to function with RAD51 and RAD51AP1 to assemble the synaptic complex. Our results help unveil a multi-faceted role of PALB2 in chromosome damage repair. Since PALB2 mutations can cause breast and other tumors or lead to Fanconi anemia, our findings are important for understanding the mechanism of tumor suppression in humans.

Dray, Eloise; Etchin, Julia; Wiese, Claudia; Saro, Dorina; Williams, Gareth J.; Hammel, Michal; Yu, Xiong; Galkin, Vitold E.; Liu, Dongqing; Tsai, Miaw-Sheue; Sy, Shirley M-H.; Egelman, Edward; Chen, Junjie; Sung, Patrick; Schild, D.

2010-08-24T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

DNA waves and water  

E-Print Network (OSTI)

Some bacterial and viral DNA sequences have been found to induce low frequency electromagnetic waves in high aqueous dilutions. This phenomenon appears to be triggered by the ambient electromagnetic background of very low frequency. We discuss this phenomenon in the framework of quantum field theory. A scheme able to account for the observations is proposed. The reported phenomenon could allow to develop highly sensitive detection systems for chronic bacterial and viral infections.

L. Montagnier; J. Aissa; E. Del Giudice; C. Lavallee; A. Tedeschi; G. Vitiello

2010-12-23T23:59:59.000Z

302

Radiation and viral DNA  

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

Radiation and viral DNA Radiation and viral DNA Name: Loretta L Lamb Age: N/A Location: N/A Country: N/A Date: N/A Question: Can viral DNA be changed through exposure to radiation? If so, what type of radiation will do this? Can these irradiated viruses cause changes in the genome of any human cells they may infect? Can these (or any) viruses actually cause cancer, or do they merely act as triggering devices for cancer? Replies: In theory, any nucleic acid (viral or otherwise) can be changed by exposure to many kinds of radiation. Depending on the type of virus, these may then change the human cells that they infect. Although there are many different things that are being implicated in causing cancers, it looks like a fairly common model involves the sequential "knockout" of several human genes. Viruses may be one cause of such gene changes, radiation and other environmental causes may also contribute. Some of these changes may be inherited through families, so it becomes more likely that the environmental factors may happen to "hit" the right places in cells to cause cancers in these families. If you ask something more specific, perhaps I can focus my response a bit more

303

Benchmarking european airports based on a profitability envelope: a break-even analysis  

Science Conference Proceedings (OSTI)

In this paper a simplified benchmarking methodology is presented. This new approach is based on the computation of a discrete envelope over distributed data points. Financial and operational data from 139 European airports in 10 countries was collected ... Keywords: airport benchmarking, break-even analysis, profit maximization

Branko Bubalo

2012-09-01T23:59:59.000Z

304

NHMFL Breaks the 100 Tesla Barrier Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network (OSTI)

NHMFL Breaks the 100 Tesla Barrier Gregory S. Boebinger, National High Magnetic Field Laboratory. 109no. 31 12404-12407 On March 22nd 2012, the NHMFL ­ Pulsed Field Facility broke the 100T tesla barrier, setting a world record of 100.75 tesla for a non-destructive magnet. By using advanced

Weston, Ken

305

Staying in the loop: structure and dynamics of Wikipedia's breaking news collaborations  

Science Conference Proceedings (OSTI)

Despite the fact that Wikipedia articles about current events are more popular and attract more contributions than typical articles, canonical studies of Wikipedia have only analyzed articles about pre-existing information. We expect the co-authoring ... Keywords: Wikipedia, breaking news, collaboration, high-tempo collaboration, multigraph, network analysis

Brian Keegan; Darren Gergle; Noshir Contractor

2012-08-01T23:59:59.000Z

306

The Monsoon over the Indian Ocean During Summer 1975. Part II: Break and Active Monsoons  

Science Conference Proceedings (OSTI)

In the second part of this paper we examine the active and break cycle of the monsoon during summer 1975. The time evolution of the flow over the Arabian Sea shocks that three main accelerations of the circulation occurred during the 1975 ...

Daniel Cadet

1983-01-01T23:59:59.000Z

307

On the Production of Aitken Nuclei from Breaking Waves and Their Role in the Atmosphere  

Science Conference Proceedings (OSTI)

A laboratory model of a breaking wave or whitecap was constructed, and the aerosol produced by it was investigated intensively. Submicron- and even Aitken-sized particles were produced: the presence of salt particles of mass <10?17 g(r<0.01 ?m) ...

Ramon J. Cipriano; Duncan C. Blanchard; Austin W. Hogan; G. Garland Lala

1983-02-01T23:59:59.000Z

308

Remote sensing of breaking wave phase speeds with application to non-linear depth inversions  

E-Print Network (OSTI)

Remote sensing of breaking wave phase speeds with application to non-linear depth inversions high-resolution remote sensing video and surface elevation records from fixed, in-situ wave gages. Wave phase speeds are extracted from the remote sensing data using a feature tracking technique, and local

Haller, Merrick

309

A Signal-processing Scheme for Passive Acoustical Mapping of Breaking Surface Waves  

Science Conference Proceedings (OSTI)

An acoustical system is described with emphasis on its signal-processing scheme. The system consists of a small broadband hydrophone array of span 8.5 m and 5-kHz bandwidth, which is able to track individual breaking surface waves by passive ...

Li Ding; David M. Farmer

1992-08-01T23:59:59.000Z

310

Calvert Cliffs 1 Reactor Vessel: Pressurized Thermal Shock Analysis for a Small Steam Line Break  

Science Conference Proceedings (OSTI)

Analysis of this Maryland reactor revealed a wide safety margin in its two-loop Combustion Engineering PWR pressure vessel for transients caused by small steam line breaks. The study employed a new method for analyzing pressurized thermal shock effects that combines several EPRI computer codes.

1984-11-01T23:59:59.000Z

311

Application of the Leak-Before-Break Approach to BWR Piping  

Science Conference Proceedings (OSTI)

By applying the leak-before-break approach in BWR safety evaluations, utilities can justify eliminating many pipe whip restraints and jet impingement shields. The report details a sample analysis of recirculation piping in a General Electric BWR and offers a procedure for ranking plant piping systems for analysis.

1987-01-07T23:59:59.000Z

312

On the perturbative generation of the higher-derivative Lorentz-breaking terms  

E-Print Network (OSTI)

In this paper, we describe the perturbative generation of the higher-derivative Lorentz-breaking terms for the gauge field, that is, the Myers-Pospelov term and the higher-derivative Carroll-Field-Jackiw term. These terms are explicitly calculated in the one-loop approximation and shown to be finite and ambiguous.

T. Mariz; J. R. Nascimento; A. Yu. Petrov

2011-11-01T23:59:59.000Z

313

Trends and breaks in per-capita carbon dioxide emissions, 1870-2028  

E-Print Network (OSTI)

We consider per-capita carbon dioxide emission trends in 16 early developed countries over the period 1870-2028. Using a multiple-break time series method we find more evidence for very early downturns in per-capita trends ...

Lanne, Markku

2003-01-01T23:59:59.000Z

314

Detection of Breaking Events in a Wind-Generated Wave Field  

Science Conference Proceedings (OSTI)

Measurements were made of the surface elevation of a fetch-limited wave field (fetch 7 km, wind speed about 6 m s?1). Good high-frequency response was attained by the use of a very thin, bare wire probe of diameter 0.13 mm. Breaking waves were ...

M. A. Weissman; S. S. Ataktürk; K. B. Katsaros

1984-10-01T23:59:59.000Z

315

Code Breaking with Quantum Computers 10 DCEMBRE 2013 15H30  

E-Print Network (OSTI)

CONFÃ?RENCE Code Breaking with Quantum Computers 10 DÃ?CEMBRE 2013 Ã? 15H30 auditorium COPL (salle POP, sprang up around this and other quantum principles, and quantum computers are its most prominent product to date. Quantum computers are not just billions of billions of times faster than your desk-top MAC

Laval, Université

316

Involvement of DNA polymerase beta in repairing oxidative damages induced by antitumor drug adriamycin  

SciTech Connect

Adriamycin (ADM) is a widely used antineoplastic drug. However, the increasing cellular resistance has become a serious limitation to ADM clinical application. The most important mechanism related to ADM-induced cell death is oxidative DNA damage mediated by reactive oxygen species (ROS). Base excision repair (BER) is a major pathway in the repair of DNA single strand break (SSB) and oxidized base. In this study, we firstly applied the murine embryo fibroblasts wild-type (pol {beta} +/+) and homozygous pol {beta} null cell (pol {beta} -/-) as a model to investigate ADM DNA-damaging effects and the molecular basis underlying these effects. Here, cellular sensitivity to ADM was examined using colorimetric assay and colony forming assay. ADM-induced cellular ROS level and the alteration of superoxide dismutase (SOD) activity were measured by commercial kits. Further, DNA strand break, chromosomal damage and gene mutation were assessed by comet assay, micronucleus test and hprt gene mutation assay, respectively. The results showed that pol {beta} -/- cells were more sensitive to ADM compared with pol {beta} +/+ cells and more severe SSB and chromosomal damage as well as higher hprt gene mutation frequency were observed in pol {beta} -/- cells. ROS level in pol {beta} -/- cells increased along with decreased activity of SOD. These results demonstrated that pol {beta} deficiency could enable ROS accumulation with SOD activity decrease, further elevate oxidative DNA damage, and subsequently result in SSB, chromosome cleavage as well as gene mutation, which may be partly responsible for the cytotoxicity of ADM and the hypersensitivity of pol {beta} -/- cells to ADM. These findings suggested that pol {beta} is vital for repairing oxidative damage induced by ADM.

Liu Shukun; Wu Mei [Department of Environmental Health, Sichuan University, West China School of Public Health, Chengdu (China); Zhang Zunzhen, E-mail: zhangzunzhen@163.co [Department of Environmental Health, Sichuan University, West China School of Public Health, Chengdu (China)

2010-08-01T23:59:59.000Z

317

LED Light Fixture Project FC1 Director's Conference Room: Life Cycle Cost and Break-even Analysis  

E-Print Network (OSTI)

LED Light Fixture Project ­ FC1 Director's Conference Room: Life Cycle Cost and Break-even Analysis. #12;LED Light Fixture Project ­ FC1 Director's Conference Room: Life Cycle Cost and Break,812 Maintenance Cost $620 $0 $97 $0 Life Cycle Cost $1,787 $1,693 $2,980 $2,980 #12;LED Light Fixture Project ­ FC

Hofmann, Hans A.

318

A Numerical Study of Breaking Kelvin-Helmholtz Billows using a Reynolds-Stress Turbulence Closure Model  

Science Conference Proceedings (OSTI)

A two-dimensional numerical study of breaking Kelvin-Helmholtz billows is presented. The turbulent breaking process is modeled using second-order closure methods to describe the small-wale turbulence, while the large-scale billow itself is ...

R. I. Sykes; W. S. Lewellen

1982-07-01T23:59:59.000Z

319

A Spar Buoy for High-Frequency Wave Measurements and Detection of Wave Breaking in the Open Ocean  

Science Conference Proceedings (OSTI)

Waves and wave breaking play a significant role in the air–sea exchanges of momentum, sea spray aerosols, and trace gases such as CO2, but few direct measurements of wave breaking have been obtained in the open ocean (far from the coast). This ...

Robin W. Pascal; Margaret J. Yelland; Meric A. Srokosz; Bengamin I. Moat; Edward M. Waugh; Daniel H. Comben; Alex G. Cansdale; Mark C. Hartman; David G. H. Coles; Ping Chang Hsueh; Timothy G. Leighton

2011-04-01T23:59:59.000Z

320

Properties of DnaB helicase in [lambda] DNA replication  

Science Conference Proceedings (OSTI)

A tailed nicked-circle DNA substrate was used to measure the rapid replication fork (RF) movement catalyzed by E. Coli DnaB helicase and DNA polymerase III holoenzyme (pol III HE) (DnaB-RFs) (30 DnaB hexamers/substrate). The DnaB RFs can efficiently utilize the DNA substrate (60% in 5 min at 30C), and the forks move at a rapid rate (550-780 bp/sec at 30C). The DnaB-RFs have an average maximal processivity of 40,000 nt, and addition of either SSB or primase increase the processivity (150,000 nt + SSB, 70,000-140,000 nt + primase). However, SSB and primase do not affect the rate of fork movement or the amount of substrate utilized in the assay. The [lambda] SS proteins are effective at transferring DnaB onto the DNA substrate (8 DnaB hexamers/substrate). The [lambda] SS proteins do not change the rate of RF movement or the amount of substrate utilized. However, the amount of synthesis measured in the assay is [approximately]2-fold higher in the presence of the [lambda] SS proteins. Therefore, the [lambda] SS proteins increase the processivity of DnaB at the RF (100,000 nt). The [lambda] SS proteins do not appear to play a role in elongation because the processivity of the RF in the presence of SSB and primase is equivalent to the processivity of the [lambda] SS-RFs. [lambda] P protein blocks DnaB helicase activity if added to the RF assay prior to initiation or during elongation. DnaB helicase is more resistant to P inhibition, if the helicase is allowed to bind to the substrate prior to addition of [lambda] P or if primase and rNTPs are included in the assay. These results suggest that the conformation of the RF complex (DNA or nucleoprotein structure) blocks the attack of P on DnaB helicase. The heat shock proteins may play an auxiliary role in mediating the effects of [lambda] P if the concentration of P protein in the cells are high.

Stephens, K.M.

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Automating DNA processing  

E-Print Network (OSTI)

Technology is currently available to identify the genetic codes responsible for physical traits and genetic diseases in both plants and animals. Regardless of whether the final goal is medical diagnosis or breeder selection, extensive time and resources must be spent in laboratory research to determine the genetic structure of the relevant organisms. DNA processing is riddled with time intensive laboratory techniques that must be improved or replaced if genotyping large numbers of samples is to be accomplished. This thesis identifies and explains modules in DNA processing and how they can be improved by automation. modules associated with genome mapping are the focus of most of the discussion. A functional biochemistry background is provided so that researchers in automation can be efficiently assimilated to future biochen-fistry/automation projects. The needs of biochemistry researchers at Texas A&M University are specifically addressed. Herein, DNA processing has been defined as a series of discrete sub-processes or process modules in order to aid scheduling of future automation projects. Target process modules (sub-processes with a high probability of automation success) have been identified. In addition, possible automation solutions have been proposed for each target module along with a characterization of fundamental design parameters. Concluding this text is a discussion of procedures in genome mapping that have not been sufficiently automated. The initial focus of this thesis is on short term solutions. However, attention is given to more conceptual solutions accompanied by the biochemistry background necessary to begin developing them. Though systems are proposed to improve the efficiency of many processes, no implementation has been attempted. Design specifications are based on observation of current laboratory techniques and the variance that is typically allowed in relevant process parameters in TAMU laboratories.

Wienen, Michael Jan

1994-01-01T23:59:59.000Z

322

DNA-based asymmetric catalysis.  

E-Print Network (OSTI)

??The goal of the research described in this thesis was to develop the general concept and methodology of DNA-based asymmetric catalysis, with the aim of… (more)

Boersma, Arnold Jacob

2009-01-01T23:59:59.000Z

323

Low energy electron induced damage to plasmid DNA pQE30  

SciTech Connect

Low energy electrons (LEEs) are produced in copious amounts by the primary radiation used in radiation therapy. The damage caused to the DNA by these secondary electrons in the energy range 5-22 eV has been studied to understand their possible role in radiation induced damage. Electrons are irradiated on dried films of plasmid DNA (pQE30) and analysed using agarose gel electrophoresis. Single strand breaks (SSBs) induced by LEE to supercoiled plasmid DNA show resonance structures at 7, 12, and 15 eV for low doses and 6, 10, and {approx}18 eV at saturation doses. The present measurements have an overall agreement with the literature that LEEs resonantly induce SSBs in DNA. Resonant peaks in the SSBs induced by LEEs at 7, 12, and 15 eV with the lowest employed dose in the current study are somewhat different from those reported earlier by two groups. The observed differences are perhaps related to the irradiation dose, conditions and the nature of DNA employed, which is further elaborated.

Kumar, S. V. K.; Pota, Tasneem; Peri, Dinakar; Dongre, Anushka D.; Rao, Basuthkar J. [Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India)

2012-07-28T23:59:59.000Z

324

Break-Even Cost for Residential Photovoltaics in the United States: Key Drivers and Sensitivities  

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

09 09 December 2009 Break-Even Cost for Residential Photovoltaics in the United States: Key Drivers and Sensitivities Paul Denholm, Robert M. Margolis, Sean Ong, and Billy Roberts National Renewable Energy Laboratory 1617 Cole Boulevard, Golden, Colorado 80401-3393 303-275-3000 * www.nrel.gov NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Operated by the Alliance for Sustainable Energy, LLC Contract No. DE-AC36-08-GO28308 Technical Report NREL/TP-6A2-46909 December 2009 Break-Even Cost for Residential Photovoltaics in the United States: Key Drivers and Sensitivities Paul Denholm, Robert M. Margolis, Sean Ong, and Billy Roberts Prepared under Task No. PVD9.1210 NOTICE This report was prepared as an account of work sponsored by an agency of the United States government.

325

Modulational instability, wave breaking and formation of large scale dipoles in the atmosphere  

E-Print Network (OSTI)

In the present Letter we use the Direct Numerical Simulation (DNS) of the Navier-Stokes equation for a two-phase flow (water and air) to study the dynamics of the modulational instability of free surface waves and its contribution to the interaction between ocean and atmosphere. If the steepness of the initial wave is large enough, we observe a wave breaking and the formation of large scale dipole structures in the air. Because of the multiple steepening and breaking of the waves under unstable wave packets, a train of dipoles is released and propagate in the atmosphere at a height comparable with the wave length. The amount of energy dissipated by the breaker in water and air is considered and, contrary to expectations, we observe that the energy dissipation in air is larger than the one in the water. Possible consequences on the wave modelling and on the exchange of aerosols and gases between air and water are discussed.

Iafrati, A; Onorato, M

2012-01-01T23:59:59.000Z

326

Modulational instability, wave breaking and formation of large scale dipoles in the atmosphere  

E-Print Network (OSTI)

In the present Letter we use the Direct Numerical Simulation (DNS) of the Navier-Stokes equation for a two-phase flow (water and air) to study the dynamics of the modulational instability of free surface waves and its contribution to the interaction between ocean and atmosphere. If the steepness of the initial wave is large enough, we observe a wave breaking and the formation of large scale dipole structures in the air. Because of the multiple steepening and breaking of the waves under unstable wave packets, a train of dipoles is released and propagate in the atmosphere at a height comparable with the wave length. The amount of energy dissipated by the breaker in water and air is considered and, contrary to expectations, we observe that the energy dissipation in air is larger than the one in the water. Possible consequences on the wave modelling and on the exchange of aerosols and gases between air and water are discussed.

A. Iafrati; A. Babanin; M. Onorato

2012-08-27T23:59:59.000Z

327

Chiral symmetry breaking patterns in the U_L(n)xU_R(n) meson model  

E-Print Network (OSTI)

Chiral symmetry breaking patterns are investigated in the U_L(n)xU_R(n) meson model. It is shown that new classes of minima of the effective potential belonging to the center of the Lie algebra exist for arbitrary flavor number n. The true ground state of the system is searched nonperturbatively and although multiple local minima of the effective potential may exist, it is argued that in regions of the parameter space applicable for the strong interaction, strictly a U_L(n)xU_R(n)->U_V(n) spontaneous symmetry breaking is possible. The reason behind this is the existence of a discrete subset of axial symmetries, which connects various U_V(n) symmetric vacua of the theory. The results are in agreement with the Vafa-Witten theorem of QCD, illustrating that it remains valid, even without gauge fields, for an effective model of the strong interaction.

G. Fejos

2012-12-14T23:59:59.000Z

328

Gauge coupling unification in heterotic string models with gauge mediated supersymmetry breaking  

Science Conference Proceedings (OSTI)

We calculate the weak scale minimal supersymmetric standard model spectrum starting from a heterotic string theory compactified on an anisotropic orbifold. Supersymmetry breaking is mediated by vectorlike exotics that arise naturally in heterotic string theories. The messengers that mediate supersymmetry breaking come in incomplete grand unified theory (GUT) multiplets and give rise to nonuniversal gaugino masses at the GUT scale. Models with nonuniversal gaugino masses at the GUT scale have the attractive feature of allowing for precision gauge coupling unification at the GUT scale with negligible contributions from threshold corrections near the unification scale. The unique features of this minimally supersymmetric standard model spectrum are light gluinos and also large mass differences between the lightest and the next-to-lightest neutralinos and charginos which could lead to interesting signatures at the colliders.

Anandakrishnan, Archana; Raby, Stuart [Department of Physics, Ohio State University, 191, W. Woodruff Ave, Columbus, Ohio 43210 (United States)

2011-04-01T23:59:59.000Z

329

Low-energy break in the spectrum of Galactic cosmic rays  

E-Print Network (OSTI)

Measurements of the low energy spectrum of Galactic Cosmic Rays (GCR) by detectors at or near the Earth are affected by Solar modulation. To overcome this difficulty, we consider nearby molecular clouds as GCR detectors outside the Solar system. Using gamma-ray observations of the clouds by the Fermi telescope we derive the spectrum of GCRs in the clouds from the observed gamma-ray emission spectrum. We find that the GCR spectrum has a low energy break with the spectral slope hardening by 1.1+/-0.3 at an energy of 9+/-3 GeV. Detection of a low-energy break enables a measurement of GCR energy density in the interstellar space 0.9+/-0.3 eV/cm3.

Neronov, A; Taylor, A M

2011-01-01T23:59:59.000Z

330

A Free Energy Landscape for Cage Breaking of Three Hard Disks  

E-Print Network (OSTI)

We investigate cage breaking in dense hard disk systems using a model of three Brownian disks confined within a circular corral. This system has a six-dimensional configuration space, but can be equivalently thought to explore a symmetric one-dimensional free energy landscape containing two energy minima separated by an energy barrier. The exact free energy landscape can be calculated as a function of system size. Results of simulations show the average time between cage breaking events follows an Arrhenius scaling when the energy barrier is large. We also discuss some of the consequences of using a one-dimensional representation to understand dynamics in a multi-dimensional space, such as diffusion acquiring spatial dependence and discontinuities in spatial derivatives of free energy.

Gary L. Hunter; Eric R. Weeks

2011-12-21T23:59:59.000Z

331

On the breaking and restoration of symmetries within the nuclear energy density functional formalism  

E-Print Network (OSTI)

We review the notion of symmetry breaking and restoration within the frame of nuclear energy density functional methods. We focus on key differences between wave-function- and energy-functional-based methods. In particular, we point to difficulties encountered within the energy functional framework and discuss new potential constraints on the underlying energy density functional that could make the restoration of broken symmetries better formulated within such a formalism. We refer to Ref.~\\cite{duguet10a} for details.

T. Duguet; J. Sadoudi

2010-10-19T23:59:59.000Z

332

Definitive Identification of the Transition between Small- to Large-Scale Clustering for Lyman Break Galaxies  

E-Print Network (OSTI)

We report angular correlation function (ACF) of Lyman Break Galaxies (LBGs) with unprecedented statistical quality on the basis of 16,920 LBGs at z=4 detected in the 1 deg^2 sky of the Subaru/XMM-Newton Deep Field. The ACF significantly departs from a power law, and shows an excess on small scale. Particularly, the ACF of LBGs with i'ACF and number density of LBGs can be explained by the cold dark matter model.

M Ouchi; T. Hamana; K. Shimasaku; T. Yamada; M. Akiyama; N. Kashikawa; M. Yoshida; K. Aoki; M. Iye; T. Saito; T. Sasaki; C. Simpson; M. Yoshida

2005-08-02T23:59:59.000Z

333

Numerical evidence of breaking of vortex lines in an ideal fluid  

E-Print Network (OSTI)

Emergence of singularity of vorticity at a single point, not related to any symmetry of the initial distribution, has been demonstrated numerically for the first time. Behavior of the maximum of vorticity near the point of collapse closely follows the dependence 1/(t0-t), where t0 is the time of collapse. This agrees with the interpretation of collapse in an ideal incompressible fluid as of the process of vortex lines breaking.

Kuznetsov, E A; Zheligovsky, V A

2001-01-01T23:59:59.000Z

334

Breaking Good  

Science Conference Proceedings (OSTI)

This article tells in images and chunky captions the story of a study into the durability of four component glass. The information from this study is of interest to vitrification experts and geochemists.

Pierce, Eric M.; Shaw, Wendy J.; Plata, Charity; Manke, Kristin L.

2011-01-01T23:59:59.000Z

335

Gauge-Invariant Formalism with a Dirac-mode Expansion for Confinement and Chiral Symmetry Breaking  

E-Print Network (OSTI)

Using the eigen-mode of the QCD Dirac operator $\\Slash D=\\gamma^\\mu D^\\mu$, we develop a manifestly gauge-covariant expansion and projection of the QCD operators such as the Wilson loop and the Polyakov loop. With this method, we perform a direct analysis of the correlation between confinement and chiral symmetry breaking in lattice QCD Monte Carlo calculation on $6^4$ at $\\beta$=5.6. Even after removing the low-lying Dirac modes, which are responsible to chiral symmetry breaking, we find that the Wilson loop obeys the area law, and the slope parameter corresponding to the string tension or the confinement force is almost unchanged. We find also that the Polyakov loop remains to be almost zero even without the low-lying Dirac modes, which indicates the $Z_3$-unbroken confinement phase. These results indicate that one-to-one correspondence does not hold for between confinement and chiral symmetry breaking in QCD.

Shinya Gongyo; Takumi Iritani; Hideo Suganuma

2012-02-19T23:59:59.000Z

336

Simulation of a main steam line break with steam generator tube rupture using trace  

Science Conference Proceedings (OSTI)

A simulation of the OECD/NEA ROSA-2 Project Test 5 was made with the thermal-hydraulic code TRACE5. Test 5 performed in the Large Scale Test Facility (LSTF) reproduced a Main Steam Line Break (MSLB) with a Steam Generator Tube Rupture (SGTR) in a Pressurized Water Reactor (PWR). The result of these simultaneous breaks is a depressurization in the secondary and primary system in loop B because both systems are connected through the SGTR. Good approximation was obtained between TRACE5 results and experimental data. TRACE5 reproduces qualitatively the phenomena that occur in this transient: primary pressure falls after the break, stagnation of the pressure after the opening of the relief valve of the intact steam generator, the pressure falls after the two openings of the PORV and the recovery of the liquid level in the pressurizer after each closure of the PORV. Furthermore, a sensitivity analysis has been performed to know the effect of varying the High Pressure Injection (HPI) flow rate in both loops on the system pressures evolution. (authors)

Gallardo, S.; Querol, A.; Verdu, G. [Departamento de Ingenieria Quimica Y Nuclear, Universitat Politecnica de Valencia, Camino de Vera s/n, 46022, Valencia (Spain)

2012-07-01T23:59:59.000Z

337

Casimir scaling and string breaking in G{sub 2} gluodynamics  

Science Conference Proceedings (OSTI)

We study the potential energy between static charges in G{sub 2} gluodynamics in three and four dimensions. Our work is based on an efficient local hybrid Monte Carlo algorithm and a multilevel Luescher-Weisz algorithm with exponential error reduction to accurately measure expectation values of Wilson and Polyakov loops. Both in three and four dimensions we show that at intermediate scales the string tensions for charges in various G{sub 2} representations scale with the second order Casimir. In three dimensions Casimir scaling is confirmed within 4% for charges in representations of dimensions 7, 14, 27, 64, 77, 77{sup '}, 182, and 189 and in four dimensions within 5% for charges in representations of dimensions 7, 14, 27, and 64. In three dimensions we detect string breaking for charges in the two fundamental representations. The scale for string breaking agrees very well with the mass of the created pair of glue lumps. Close to the string breaking distance Casimir scaling between adjoint and defining representation is violated by 2.5%. The analytical prediction for the continuum string tension is confirmed for the defining representation in three dimensions.

Wellegehausen, Bjoern H.; Wipf, Andreas; Wozar, Christian [Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universitaet Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

2011-01-01T23:59:59.000Z

338

A Parametric Study of a Large Break in Reactor Inlet Header of CANDU6 Reactors Using RELAP5 Code  

SciTech Connect

A large break loss of coolant accident in a CANDU can lead to degraded fuel cooling in a large number of fuel channels due to the apparition of a prolonged flow stagnation period in the downstream core pass. The paper presents a parametric study of a reactor inlet header break. The parametric survey includes: the size of the break, the choked flow model employed, the emergency core cooling (ECC) performance and the core nodalization. The study is performed with RELAP5/SCDAP mod 3.4 and the results are compared with the safety analysis results. (authors)

Prisecaru, Ilie; Dupleac, Daniel; Ghitescu, Petre [Power Plant Engineering Faculty, Politehnica Univ., 313 Splaiul Independentei, Bucharest (Romania); Biro, Lucian [National Commission for Nuclear Activities Control, 14 Libertatii Blvd., Bucharest (Romania)

2006-07-01T23:59:59.000Z

339

Numerical simulation of three-dimensional breaking waves on a gravel slope using a two-phase flow Navier-Stokes model  

Science Conference Proceedings (OSTI)

Wave breaking is mainly a three-dimensional flow problem characterized by wave energy dissipation due to turbulence. The understanding of the wave breaking mechanism on a beach is essential in studying coastal processes. The complexity of the wave-induced ... Keywords: CFD, Porous medium, Two phase, VOF, Wave breaking

P. Higuera; M. Del Jesus; J. L. Lara; I. J. Losada; Y. Guanche; G. Barajas

2013-07-01T23:59:59.000Z

340

Influence of Mean Water Depth and a Subsurface Sandbar on the Onset and Strength of Wave Breaking  

Science Conference Proceedings (OSTI)

Wave breaking in the open ocean and coastal zones remains an intriguing yet incompletely understood process, with a strong observed association with wave groups. Recent numerical study of the evolution of fully nonlinear, two-dimensional deep ...

Jin-Bao Song; Michael L. Banner

2004-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

TITAN code development for application to a PWR steam line break accident : final report 1983-1984  

E-Print Network (OSTI)

Modification of the TITAN computer code which enables it to be applied to a PWR steam line break accident has been accomplished. The code now has the capability of simulating an asymmetric inlet coolant temperature transient ...

Tsai, Chon-Kwo

1984-01-01T23:59:59.000Z

342

Introduction of Break-Out Session 2 of the 2011 International PV Module Quality Assurance Forum(Presentation)  

Science Conference Proceedings (OSTI)

This presentation outlines the goals and specific tasks of break-out session 2 of the 2011 International PV Module Quality Assurance Forum, along with a review of accelerated stress tests used for photovoltaics (PV).

Wohlgemuth, J.; Kurtz, S.; Sample, T.; Yamamichi, M.

2011-07-01T23:59:59.000Z

343

On Determining the Onset and Strength of Breaking for Deep Water Waves. Part I: Unforced Irrotational Wave Groups  

Science Conference Proceedings (OSTI)

Finding a robust threshold variable that determines the onset of breaking for deep water waves has been an elusive problem for many decades. Recent numerical studies of the unforced evolution of two-dimensional nonlinear wave trains have ...

Jin-Bao Song; Michael L. Banner

2002-09-01T23:59:59.000Z

344

Horizontal Scales of Variability over the Middle Atlantic Bight Shelf Break and Continental Rise from Finescale Observations  

Science Conference Proceedings (OSTI)

Observations with fine horizontal resolution are used to identify the horizontal scales of variability over the Middle Atlantic Bight (MAB) shelf break and continental rise. Spray gliders collected observations along two alongshelf transects over ...

Robert E. Todd; Glen G. Gawarkiewicz; W. Brechner Owens

2013-01-01T23:59:59.000Z

345

Sequence independent amplification of DNA  

DOE Patents (OSTI)

The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example, the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei. 25 figs.

Bohlander, S.K.

1998-03-24T23:59:59.000Z

346

Sequence independent amplification of DNA  

DOE Patents (OSTI)

The present invention is a rapid sequence-independent amplification procedure (SIA). Even minute amounts of DNA from various sources can be amplified independent of any sequence requirements of the DNA or any a priori knowledge of any sequence characteristics of the DNA to be amplified. This method allows, for example the sequence independent amplification of microdissected chromosomal material and the reliable construction of high quality fluorescent in situ hybridization (FISH) probes from YACs or from other sources. These probes can be used to localize YACs on metaphase chromosomes but also--with high efficiency--in interphase nuclei.

Bohlander, Stefan K. (Chicago, IL)

1998-01-01T23:59:59.000Z

347

Physical Interactions between Mcm10, DNA, and DNA Polymerase [alpha  

SciTech Connect

Mcm10 is an essential eukaryotic protein required for the initiation and elongation phases of chromosomal replication. Specifically, Mcm10 is required for the association of several replication proteins, including DNA polymerase {alpha} (pol {alpha}), with chromatin. We showed previously that the internal (ID) and C-terminal (CTD) domains of Mcm10 physically interact with both single-stranded (ss) DNA and the catalytic p180 subunit of pol {alpha}. However, the mechanism by which Mcm10 interacts with pol {alpha} on and off DNA is unclear. As a first step toward understanding the structural details for these critical intermolecular interactions, x-ray crystallography and NMR spectroscopy were used to map the binary interfaces between Mcm10-ID, ssDNA, and p180. The crystal structure of an Mcm10-ID {center_dot} ssDNA complex confirmed and extended our previous evidence that ssDNA binds within the oligonucleotide/oligosaccharide binding-fold cleft of Mcm10-ID. We show using NMR chemical shift perturbation and fluorescence spectroscopy that p180 also binds to the OB-fold and that ssDNA and p180 compete for binding to this motif. In addition, we map a minimal Mcm10 binding site on p180 to a small region within the p180 N-terminal domain (residues 286-310). These findings, together with data for DNA and p180 binding to an Mcm10 construct that contains both the ID and CTD, provide the first mechanistic insight into how Mcm10 might use a handoff mechanism to load and stabilize pol {alpha} within the replication fork.

Warren, Eric M.; Huang, Hao; Fanning, Ellen; Chazin, Walter J.; Eichman, Brandt F.; (Vanderbilt)

2009-10-21T23:59:59.000Z

348

Break-Even Cost for Residential Solar Water Heating in the United States: Key Drivers and Sensitivities  

SciTech Connect

This paper examines the break-even cost for residential rooftop solar water heating (SWH) technology, defined as the point where the cost of the energy saved with a SWH system equals the cost of a conventional heating fuel purchased from the grid (either electricity or natural gas). We examine the break-even cost for the largest 1,000 electric and natural gas utilities serving residential customers in the United States as of 2008. Currently, the break-even cost of SWH in the United States varies by more than a factor of five for both electricity and natural gas, despite a much smaller variation in the amount of energy saved by the systems (a factor of approximately one and a half). The break-even price for natural gas is lower than that for electricity due to a lower fuel cost. We also consider the relationship between SWH price and solar fraction and examine the key drivers behind break-even costs. Overall, the key drivers of the break-even cost of SWH are a combination of fuel price, local incentives, and technical factors including the solar resource location, system size, and hot water draw.

Cassard, H.; Denholm, P.; Ong, S.

2011-02-01T23:59:59.000Z

349

When DNA Needs to Stand Up and Be Counted  

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

When DNA Needs to Stand Up and Be Counted Print DNA microarrays are small metal, glass, or silicon chips covered with patterns of short single-stranded DNA (ssDNA). These "DNA...

350

Energy Blog | Department of Energy  

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

4, 2012 4, 2012 The National Renewable Energy Lab's (NREL) utility rate database is a great resource for developers entering the Apps for Energy competition. | Map courtesy of NREL. Developer Resources for Apps for Energy Are you interested in participating in the Apps for Energy competition? Be sure to check out this list of resources that can help developers create energy apps. April 3, 2012 The DNA replication origin recognition complex (ORC) is a six-protein machine with a slightly twisted half-ring structure (yellow). ORC is proposed to wrap around and bend approximately 70 base pairs of double stranded DNA (red and blue). When a replication initiator Cdc6 (green) joins ORC, the partial ring is now complete and ready to load another protein onto the DNA. This last protein (not shown) is the enzyme that unwinds the double stranded DNA so each strand can be replicated. | Illustration courtesy of Brookhaven Lab.

351

Energy Blog | Department of Energy  

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

April 4, 2012 April 4, 2012 The National Renewable Energy Lab's (NREL) utility rate database is a great resource for developers entering the Apps for Energy competition. | Map courtesy of NREL. Developer Resources for Apps for Energy Are you interested in participating in the Apps for Energy competition? Be sure to check out this list of resources that can help developers create energy apps. April 3, 2012 The DNA replication origin recognition complex (ORC) is a six-protein machine with a slightly twisted half-ring structure (yellow). ORC is proposed to wrap around and bend approximately 70 base pairs of double stranded DNA (red and blue). When a replication initiator Cdc6 (green) joins ORC, the partial ring is now complete and ready to load another protein onto the DNA. This last protein (not shown) is the enzyme that unwinds the double stranded DNA so each strand can be replicated. | Illustration courtesy of Brookhaven Lab.

352

A Solution to the Strong CP Problem with Gauge-Mediated Supersymmetry Breaking  

E-Print Network (OSTI)

We demonstrate that a certain class of low scale supersymmetric ``Nelson-Barr'' type models can solve the strong and supersymmetric CP problems while at the same time generating sufficient weak CP violation in the $K^{0}-\\bar{K}^{0}$ system. In order to prevent one-loop corrections to $\\bar{\\theta}$ which violate bounds coming from the neutron electric dipole moment (EDM), one needs a scheme for the soft supersymmetry breaking parameters which can naturally give sufficient squark degeneracies and proportionality of trilinear soft supersymmetry-breaking parameters to Yukawa couplings. We show that a gauge-mediated supersymmetry breaking sector can provide the needed degeneracy and proportionality, though that proves to be a problem for generic Nelson-Barr models. The workable model we consider here has the Nelson-Barr mass texture enforced by a gauge symmetry; one also expects a new U(1) gauge superfield with mass in the TeV range. The resulting model is predictive. We predict a measureable neutron EDM and the existence of extra vector-like quark superfields which can be discovered at the LHC. Because the $3\\times 3$ Cabbibo-Kobayashi-Maskawa matrix is approximately real, the model also predicts a flat unitarity triangle and the absence of substantial CP violation in the $B$ system at future $B$ factories. We discuss the general issues pertaining to the construction of such a workable model and how they lead to the successful strategy. A detailed renormalization group study is then used to establish the feasibility of the model considered.

Otto C. W. Kong; Brian D. Wright

1998-02-03T23:59:59.000Z

353

Double Ended Guillotine Break in a Prismatic Block VHTR Lower Plenum Air Ingress Scenario  

E-Print Network (OSTI)

The double ended guillotine break leading to density-driven air ingress has been identified as a low probability yet high consequence event for Very High Temperature Reactor (VHTR). The lower plenum of the VHTR contains the core support structure and is composed of graphite. During an air ingress event, oxidation of the graphite structure under high temperature conditions in an oxygen containing environment could degrade the integrity of the core support structure. Following this large break, air from the reactor containment will begin to enter the lower plenum via two mechanisms: diffusion or density driven stratified flow. The large difference in time scales between the mechanisms leads to the need to perform high fidelity experimental studies to investigate the dominant the air ingress mechanism. A scaled test facility has been designed and built that allows the acquisition of velocity measurements during stratification after a pipe break. A non-intrusive optical measurement technique provides full-field velocity measurements profiles of the two species Particle Image Velocimetry (PIV). The data allow a more developed understanding of the fundamental flow features, the development of improved models, and possible mitigation strategies in such a scenario.Two brine-water experiments were conducted with different break locations. Flow fronts were analyzed and findings concluded that the flow has a constant speed through the pipe after the initial lock exchange. The time in which the flow enters the lower plenum is an important factor because it provides the window of opportunity for mitigation strategies in an actual reactor scenario. For both cases the flow of the heavier density liquid (simulating air ingress from the reactor containment) from the pipe enters the reactor vessel in under 6 seconds. The diffusion velocity and heavy flow front of the stratified flow layer were compared for the SF6/He gas case. It is seen that the diffusion plays less of a role as the transport mechanism in comparison to the density-driven stratified flow since the velocity of the diffusion is two orders of magnitude smaller than the velocity of the stratified flow mechanism. This is the reason for the need for density-driven stratified flow investigations following a LOCA. These investigations provided high-quality data for CFD validation in order for these models to depict the basic phenomena occurring in an air ingress scenario.

Hartley, Jessica

2011-08-01T23:59:59.000Z

354

Studying the Breaking Mechanism of Polymer-Based In-Situ Gelled Acids using Solid Breaker  

E-Print Network (OSTI)

In situ gelled acids that are based on polymers have been used in the field for several years as an acid diversion agent. These acids should not cause permanent formation damage, and should clean-up rapidly and completely when the well is put back on production. However, recent lab studies indicated that a significant amount of gel was retained inside the core even when the recommended breaker concentration was used. This gel significantly reduced the core permeability. Therefore, the objective of this study is to examine the working mechanisms of the solid breaker and the factors that affect the breaking time. The flowback of the spent acid and the core damage induced by it will also be assessed in detail. Viscosity and rheological experimental studies were conducted using polymer-based in situ gelled acids that used Zr as a crosslinker agent. To form the gel, this acid was neutralized using Pink Desert limestone to pH 3.5-4.The rheological properties of the gel were measured under different breaking conditions for 2 hr using HPHT rotational and oscillatory rheometers. Temperature (150 to 250 degrees F), shear rate (0.1 to 1000 s^-1), and breaker concentrations (0 to 32 lb/Mgal) were the main parameters that were investigated in this study. Experimental results showed that there is no need to add more than 16-ppg breaker concentration at 150 degrees F, while 4-ppg breaker concentration is enough at temperatures higher than 200 degrees F. A full breaking of these acids was obtained when the values of elastic modulus (G') were equalized with the viscose modules (G"). An HPHT filter press was used to simulate the flowback of the spent acid. Viscosity measurements of filtered fluids were used to determine the degree of gel degradation. Carbonate cores that had a 2.5 in. diameter and 0.25 in.thickness were used. Temperature (75 to 250 degrees F) and breaker concentrations (0 to 16 lb/Mgal) were the main parameters that were investigated in this study. Experimental results showed that there was always a gel left inside the rock, and such caused permeability reduction. Time needed to flowback the solution decreased by 50% when the temperature was increased from 150 to 200 degrees F, while it decreased by only 30% when the breaker concentration was doubled. At 150 degrees F, 16-ppg breaker concentration was recommended for breaking the gel. At higher temperatures (>150 degrees F), 8-ppg breaker concentration was enough to help degrade the gel.

Tian, Zhida

2012-08-01T23:59:59.000Z

355

BREAKING OF AXIAL AND REFLECTION SYMMETRIES IN SPONTANEOUS FISSION OF FERMIUM ISOTOPES  

SciTech Connect

The nuclear fission phenomenon is a magnificent example of a quantal collective motion during which the nucleus evolves in a multidimensional space representing shapes with different geometries. The triaxial degrees of freedom are usually important around the inner fission barrier, and reduce the fission barrier height by several MeV. Beyond the inner barrier, reflection-asymmetric shapes corresponding to asymmetric elongated fragments come into play. We discuss the interplay between different symmetry breaking mechanisms in the case of even-even fermium isotopes using the Skyrme HFB formalism.

Staszczak, A. [Maria Curie-Sklodowska University; Nazarewicz, Witold [ORNL; Baran, Andrzej K [ORNL

2011-01-01T23:59:59.000Z

356

Charge independence, charge symmetry breaking in the S-wave nucleon-nucleon interaction, and renormalization  

SciTech Connect

We study the interplay between charge symmetry breaking and renormalization in the NN system for S-waves. We find a set of universality relations which disentangle explicitly the known long distance dynamics from low energy parameters and extend them to the Coulomb case. We analyze within such an approach the One-Boson-Exchange potential and the theoretical conditions which allow to relate the proton-neutron, proton-proton and neutron-neutron scattering observables without the introduction of extra new parameters and providing good phenomenological success.

Alvaro Calle Cordon,Manuel Pavon Valderrama,Enrique Ruiz Arriola

2012-02-01T23:59:59.000Z

357

Comparative tests of isospin-symmetry-breaking corrections to superallowed 0+-to-0+ nuclear beta decay  

E-Print Network (OSTI)

We present a test with which to evaluate the calculated isospin-symmetry-breaking corrections to superallowed 0+-to-0+ nuclear beta decay. The test is based on the corrected experimental Ft values being required to satisfy conservation of the vector current (CVC). When applied to six sets of published calculations, the test demonstrates quantitatively that only one set -- the one based on the shell model with Saxon-Woods radial wave functions -- provides satisfactory agreement with CVC. This test can easily be applied to any sets of calculated correction terms that are produced in future.

Towner, I S

2010-01-01T23:59:59.000Z

358

Cellular responses to environmental DNA damage  

Science Conference Proceedings (OSTI)

This volume contains the proceedings of the conference entitled Cellular Responses to Environmental DNA Damage held in Banff,Alberta December 1--6, 1991. The conference addresses various aspects of DNA repair in sessions titled DNA repair; Basic Mechanisms; Lesions; Systems; Inducible Responses; Mutagenesis; Human Population Response Heterogeneity; Intragenomic DNA Repair Heterogeneity; DNA Repair Gene Cloning; Aging; Human Genetic Disease; and Carcinogenesis. Individual papers are represented as abstracts of about one page in length.

Not Available

1994-08-01T23:59:59.000Z

359

A LYMAN BREAK GALAXY IN THE EPOCH OF REIONIZATION FROM HUBBLE SPACE TELESCOPE GRISM SPECTROSCOPY  

SciTech Connect

We present observations of a luminous galaxy at z = 6.573-the end of the reionization epoch-which has been spectroscopically confirmed twice. The first spectroscopic confirmation comes from slitless Hubble Space Telescope Advanced Camera for Surveys grism spectra from the PEARS survey (Probing Evolution And Reionization Spectroscopically), which show a dramatic continuum break in the spectrum at rest frame 1216 A. The second confirmation is done with Keck + DEIMOS. The continuum is not clearly detected with ground-based spectra, but high wavelength resolution enables the Ly{alpha} emission line profile to be determined. We compare the line profile to composite line profiles at z = 4.5. The Ly{alpha} line profile shows no signature of a damping wing attenuation, confirming that the intergalactic gas is ionized at z = 6.57. Spectra of Lyman breaks at yet higher redshifts will be possible using comparably deep observations with IR-sensitive grisms, even at redshifts where Ly{alpha} is too attenuated by the neutral intergalactic medium to be detectable using traditional spectroscopy from the ground.

Rhoads, James E.; Malhotra, Sangeeta; Cohen, Seth; Zheng Zhenya [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Dickinson, Mark [National Optical Astronomy Observatory, Tucson, AZ (United States); Pirzkal, Norbert; Grogin, Norman; Koekemoer, Anton; Peth, Michael A. [Space Telescope Science Institute, Baltimore, MD (United States); Spinrad, Hyron [University of California, Berkeley, CA (United States); Reddy, Naveen [University of California, Riverside, CA (United States); Hathi, Nimish [Observatories of the Carnegie Institution of Washington, Pasadena, CA (United States); Budavari, Tamas [Johns Hopkins University, Baltimore, MD (United States); Ferreras, Ignacio [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT (United Kingdom); Gardner, Jonathan P. [NASA Goddard Space Flight Center, Astrophysics Science Division, Observational Cosmology Laboratory, Code 665, Greenbelt, MD 20771 (United States); Gronwall, Caryl [Department of Astronomy and Astrophysics, and Institute for Gravitation and the Cosmos, The Pennsylvania State University, University Park, PA 16802 (United States); Haiman, Zoltan [Columbia University, New York, NY (United States); Kuemmel, Martin [Universitaets-Sternwarte Muenchen, Scheinerstr. 1, D-81679 Muenchen (Germany); Meurer, Gerhardt, E-mail: James.Rhoads@asu.edu [International Centre for Radio Astronomy Research, University of Western Australia, M468, 35 Stirling Highway, Crawley, WA 6009 (Australia); and others

2013-08-10T23:59:59.000Z

360

High-spin structures of 124-131Te: Competition of proton and neutron pair breakings  

E-Print Network (OSTI)

The 124-131Te nuclei have been produced as fission fragments in two fusion reactions induced by heavy-ions (12C + 238U at 90 MeV bombarding energy and 18O + 208Pb at 85 MeV) and studied with the Euroball array. Their high-spin level schemes have been extended to higher excitation energy from the triple gamma-ray coincidence data. The gamma-gamma angular correlations have been analyzed in order to assign spin and parity values to many observed states. Moreover the half-lives of isomeric states have been measured from the delayed coincidences between the fission-fragment detector SAPhIR and Euroball, as well as from the timing information of the Ge detectors. The behaviors of the yrast structures identified in the present work are first discussed in comparison with the general features known in the mass region, particularly the breakings of neutron pairs occupying the nuh11/2 orbit identified in the neighboring Sn nuclei. The experimental level schemes are then compared to shell-model calculations performed in this work. The analysis of the wave functions shows the effects of the proton-pair breaking along the yrast lines of the heavy Te isotopes.

A. Astier; M. -G. Porquet; Ts. Venkova; Ch. Theisen; G. Duchene; F. Azaiez; G. Barreau; D. Curien; I. Deloncle; O. Dorvaux; B. J. P. Gall; M. Houry; R. Lucas; N. Redon; M. Rousseau; O. Stezowski

2013-12-17T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

PT-symmetry breaking in complex nonlinear wave equations and their deformations  

E-Print Network (OSTI)

We investigate complex versions of the Korteweg-deVries equations and an Ito type nonlinear system with two coupled nonlinear fields. We systematically construct rational, trigonometric/hyperbolic, elliptic and soliton solutions for these models and focus in particular on physically feasible systems, that is those with real energies. The reality of the energy is usually attributed to different realisations of an antilinear symmetry, as for instance PT-symmetry. It is shown that the symmetry can be spontaneously broken in two alternative ways either by specific choices of the domain or by manipulating the parameters in the solutions of the model, thus leading to complex energies. Surprisingly the reality of the energies can be regained in some cases by a further breaking of the symmetry on the level of the Hamiltonian. In many examples some of the fixed points in the complex solution for the field undergo a Hopf bifurcation in the PT-symmetry breaking process. By employing several different variants of the symmetries we propose many classes of new invariant extensions of these models and study their properties. The reduction of some of these models yields complex quantum mechanical models previously studied.

Andrea Cavaglia; Andreas Fring; Bijan Bagchi

2011-03-09T23:59:59.000Z

362

Gauge invariant non-linear electrodynamics motivated by a spontaneous breaking of the Lorentz symmetry  

E-Print Network (OSTI)

We introduce a new version of non-linear electrodynamics which is produced by a spontaneous symmetry breaking of Lorentz invariance induced by the non-zero expectation value of the electromagnetic field strength. The symmetry breaking potential is argued to effectively arise from the integration of massive gauge bosons and fermions in an underlying fundamental theory. All possible choices of the vacuum lead only to the remaining invariant subgroups T(2) and HOM(2). We explore the plane wave solutions of the linearized sector of the model for an arbitrary vacuum. They present two types of dispersion relations. One corresponds to the case of the usual Maxwell electrodynamics with the standard polarization properties of the fields. The other dispersion relation involves anisotropies determined by the structure of the vacuum. The model is stable in the small Lorentz invariance violation approximation. We have embedded our model in the photon sector of the Standard Model Extension in order to set bounds for our parameters. The one-way anisotropic speed of light is calculated for a general vacuum and its isotropic component is strongly bounded by ${\\tilde \\delta c}/c alternative definition for the difference of the two-way speed of light in perpendicular directions $\\Delta c$, which is also strongly bounded by ${\\Delta c}/c energy of the model with the cosmological constant and propose a connection between the vacuum fields and the intergalactic magnetic fields.

Jorge Alfaro; Luis F. Urrutia

2009-12-16T23:59:59.000Z

363

PT-symmetry breaking in complex nonlinear wave equations and their deformations  

E-Print Network (OSTI)

We investigate complex versions of the Korteweg-deVries equations and an Ito type nonlinear system with two coupled nonlinear fields. We systematically construct rational, trigonometric/hyperbolic, elliptic and soliton solutions for these models and focus in particular on physically feasible systems, that is those with real energies. The reality of the energy is usually attributed to different realisations of an antilinear symmetry, as for instance PT-symmetry. It is shown that the symmetry can be spontaneously broken in two alternative ways either by specific choices of the domain or by manipulating the parameters in the solutions of the model, thus leading to complex energies. Surprisingly the reality of the energies can be regained in some cases by a further breaking of the symmetry on the level of the Hamiltonian. In many examples some of the fixed points in the complex solution for the field undergo a Hopf bifurcation in the PT-symmetry breaking process. By employing several different variants of the sym...

Cavaglia, Andrea; Bagchi, Bijan

2011-01-01T23:59:59.000Z

364

Vibration and Nonlinear Resonance in the Break-up of an Underwater Bubble  

E-Print Network (OSTI)

We use high-speed X-ray phase-contrast imaging, weakly nonlinear analysis and boundary integral simulations to characterize the final stage of underwater bubble break-up. The X-ray imaging study shows that an initial azimuthal perturbation to the shape of the bubble neck gives rise to oscillations that increasingly distort the cross-section shape. These oscillations terminate in a pinch-off where the bubble surface develops concave regions that contact similar to what occurs when two liquid drops coalesce. We also present a weakly nonlinear analysis that shows that this coalescence-like mode of pinch-off occurs when the initial shape oscillation interferes constructively with the higher harmonics it generates and thus reinforce each other's effects in bringing about bubble break-up. Finally we present numerical results that confirm the weakly nonlinear analysis scenario as well as provide insight into observed shape reversals. They demonstrate that when the oscillations interfere destructively, a qualitativel...

Lai, Lipeng; Fezzaa, Kamel; Zhang, Wendy W; Nagel, Sidney R

2013-01-01T23:59:59.000Z

365

Regulation of DNA damage tolerance : studies of the translesion synthesis DNA ploymerase eta in Saccharomyces cerevisiae  

E-Print Network (OSTI)

All organisms must control the effects of DNA damage to protect the integrity of their genomes. In addition to DNA repair, this requires DNA damage tolerance pathways, which allow the continuation of essential processes ...

Woodruff, Rachel Van Etten

2008-01-01T23:59:59.000Z

366

Characterization of nanoparticle-DNA conjugate and control of DNA conformation on particle surface  

E-Print Network (OSTI)

Nano-science has exploited the hybridization and de-hybridization phenomena of DNA which are one of its fundamental functions. In particular, conjugates of gold nanoparticles and DNA (Au NP-DNA) have been extensively ...

Park, Sunho, 1976-

2009-01-01T23:59:59.000Z

367

Garcinol, a Histone Acetyltransferase Inhibitor, Radiosensitizes Cancer Cells by Inhibiting Non-Homologous End Joining  

SciTech Connect

Purpose: Non-homologous end joining (NHEJ), a major pathway used to repair DNA double-strand breaks (DSBs) generated by ionizing radiation (IR), requires chromatin remodeling at DSB sites through the acetylation of histones by histone acetyltransferases (HATs). However, the effect of compounds with HAT inhibitory activities on the DNA damage response (DDR), including the NHEJ and cell cycle checkpoint, as well as on the radiosensitivity of cancer cells, remains largely unclear. Here, we investigated whether garcinol, a HAT inhibitor found in the rinds of Garcinia indica fruit (called mangosteens), has effects on DDR, and whether it can be used for radiosensitization. Methods and Materials: The following assays were used to examine the effect of garcinol on the inhibition of DSB repair, including the following: a conventional neutral comet assay; a cell-based assay recently developed by us, in which NHEJ repair of DSBs on chromosomal DNA was evaluated; the micrococcal nuclease sensitivity assay; and immunoblotting for autophosphorylation of DNA-dependent protein kinase catalytic subunit (DNA-PKcs). We assessed the effect of garcinol on the cell cycle checkpoint after IR treatment by analyzing the phosphorylation levels of checkpoint kinases CHK1 and CHK2 and histone H3, and by cell cycle profile analysis using flow cytometry. The radiosensitizing effect of garcinol was assessed by a clonogenic survival assay, whereas its effects on apoptosis and senescence were examined by annexin V and senescence-associated {beta}-galactosidase (SA-{beta}-Gal) staining, respectively. Results: We found that garcinol inhibits DSB repair, including NHEJ, without affecting cell cycle checkpoint. Garcinol radiosensitized A549 lung and HeLa cervical carcinoma cells with dose enhancement ratios (at 10% surviving fraction) of 1.6 and 1.5, respectively. Cellular senescence induced by IR was enhanced by garcinol. Conclusion: These results suggest that garcinol is a radiosensitizer that inhibits NHEJ and facilitates senescence without impairing activation of the cell cycle checkpoint.

Oike, Takahiro [Division of Multistep Carcinogenesis, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan) [Division of Multistep Carcinogenesis, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma (Japan); Ogiwara, Hideaki [Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)] [Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Torikai, Kohta [Gunma University Heavy Ion Medical Center, Maebashi, Gunma (Japan)] [Gunma University Heavy Ion Medical Center, Maebashi, Gunma (Japan); Nakano, Takashi [Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma (Japan)] [Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma (Japan); Yokota, Jun [Division of Multistep Carcinogenesis, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)] [Division of Multistep Carcinogenesis, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan); Kohno, Takashi, E-mail: tkkohno@ncc.go.jp [Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)] [Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)

2012-11-01T23:59:59.000Z

368

Inhibition of homologous recombination repair in irradiated tumor cells pretreated with Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin  

Science Conference Proceedings (OSTI)

In order to investigate the mechanism of radio-sensitization by an Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG), we studied repair of DNA double strand breaks (DSBs) in irradiated human cells pre-treated with 17-AAG. DSBs are thought to be the critical target for radiation-induced cell death. Two human tumor cell lines DU145 and SQ-5 which showed clear radio-sensitization by 17-AAG revealed a significant inhibition of DSB repair, while normal human cells which did not show radio-sensitization by the drug indicated no change in the DSB repair kinetics with 17-AAG. We further demonstrated that BRCA2 was a novel client protein for Hsp90, and 17-AAG caused the degradation of BRCA2 and in turn altered the behavior of Rad51, a critical protein for homologous recombination (HR) pathway of DSB repair. Our data demonstrate for the first time that 17-AAG inhibits the HR repair process and could provide a new therapeutic strategy to selectively result in higher tumor cell killing.

Noguchi, Miho [Graduate School of Science and Technology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Yu, Dong [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Hirayama, Ryoichi [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Ninomiya, Yasuharu [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Sekine, Emiko [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Kubota, Nobuo [Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2 Ami, Ami-machi, Inashiki-gun, Ibaraki 300-0394 (Japan); Ando, Koichi [Graduate School of Science and Technology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Okayasu, Ryuichi [Heavy-Ion Radiobiology Research Group, National Institute of Radiological Sciences, 4-9-1, Anagawa, Inage-ku, Chiba 263-8555 (Japan)]. E-mail: rokayasu@nirs.go.jp

2006-12-22T23:59:59.000Z

369

Transgenic plants are sensitive bioindicators of nuclear pollution caused by the Chernobyl accident  

SciTech Connect

To evaluate the genetic consequences of radioactive contamination originating from the Nuclear reactor accident of Chernobyl on indigenous populations of plants and animals, it is essential to determine the rates of accumulating genetic changes in chronically irradiated populations. An increase in germline mutation rates in humans living close to the Chernobyl Nuclear Power Plant site, and a two- to tenfold increase in germline mutations in barn swallows breeding in Chernobyl have been reported. Little is known, however, about the effects of chronic irradiation on plant genomes. Ionizing radiation causes double-strand breaks in DNA, which are repaired via illegitimate or homologous recombination. The authors make use of Arabidopsis thaliana plants carrying a {beta}-glucuronidase marker gene as a recombination substrate to monitor genetic alterations in plant populations, which are caused by nuclear pollution of the environment around Chernobyl. A significant increase in somatic intrachromosomal recombination frequencies was observed at nuclear pollution levels from 0.1--900 Ci/km{sup 2}, consistent with an increase in chromosomal aberrations. This bioindicator may serve as a convenient and ethically acceptable alternative to animal systems.

Kovalchuk, I.; Kovalchuk, O. [Ivano-Frankivsk State Medical Academy (Ukraine)]|[Friedrich Miescher Inst., Basel (Switzerland); Arkhipov, A. [Chernobyl Scientific and Technical Center of International Research (Ukraine); Hohn, B. [Friedrich Miescher Inst., Basel (Switzerland)

1998-11-01T23:59:59.000Z

370

A nanotube based electron microbeam cellular irradiator for radiobiology research  

Science Conference Proceedings (OSTI)

A prototype cellular irradiator utilizing a carbon nanotube (CNT) based field emission electron source has been developed for microscopic image-guided cellular region irradiation. The CNT cellular irradiation system has shown great potential to be a high temporal and spatial resolution research tool to enable researchers to gain a better understanding of the intricate cellular and intercellular microprocesses occurring following radiation deposition, which is essential to improving radiotherapy cancer treatment outcomes. In this paper, initial results of the system development are reported. The relationship between field emission current, the dose rate, and the dose distribution has been investigated. A beam size of 23 {mu}m has been achieved with variable dose rates of 1-100 Gy/s, and the system dosimetry has been measured using a radiochromic film. Cell irradiation has been demonstrated by the visualization of H2AX phosphorylation at DNA double-strand break sites following irradiation in a rat fibroblast cell monolayer. The prototype single beam cellular irradiator is a preliminary step to a multipixel cell irradiator that is under development.

Bordelon, David E. [Curriculum in Applied and Materials Sciences, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Zhang Jian; Graboski, Sarah; Cox, Adrienne; Schreiber, Eric; Chang, Sha [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Zhou, Otto Z. [Department of Physics and Astronomy, Curriculum in Applied and Materials Sciences, and Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)

2008-12-15T23:59:59.000Z

371

Preparation Of Dna-Containing Extract For Pcr Amplification  

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

Preparation Of Dna-Containing Extract For Pcr Amplification Preparation Of Dna-Containing Extract For Pcr Amplification The method may provide a DNA-containing extract sufficiently...

372

Break-Even Cost for Residential Solar Water Heating in the United States: Key Drivers and Sensitivities  

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

Break-even Cost for Residential Break-even Cost for Residential Solar Water Heating in the United States: Key Drivers and Sensitivities Hannah Cassard, Paul Denholm, and Sean Ong Technical Report NREL/TP-6A20-48986 February 2011 NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC. National Renewable Energy Laboratory 1617 Cole Boulevard Golden, Colorado 80401 303-275-3000 * www.nrel.gov Contract No. DE-AC36-08GO28308 Break-even Cost for Residential Solar Water Heating in the United States: Key Drivers and Sensitivities Hannah Cassard, Paul Denholm, and Sean Ong Prepared under Task No. SS10.2110 Technical Report

373

On the breaking of a plasma wave in a thermal plasma. I. The structure of the density singularity  

SciTech Connect

The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wave breaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical 'peakon' form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions. The after-wavebreak regime is then examined, and a semi-analytical model of the density evolution is constructed. Finally the results of two dimensional particle in cell simulations for different initial electron distribution functions are compared, and the role of thermal effects in enhancing particle injection is noted.

Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi [QuBS, Japan Atomic Energy Agency, 1-8-7 Umemidai, Kizugawa, Kyoto 619-0215 (Japan); Bulanov, Stepan S. [University of California, Berkeley, California 94720 (United States); Schroeder, Carl B.; Esarey, Eric [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Califano, Francesco; Pegoraro, Francesco [Physics Department, University of Pisa, Pisa 56127 (Italy)

2012-11-15T23:59:59.000Z

374

Cellulose solventbased biomass pretreatment breaks highly ordered hydrogen bonds in cellulose fibers of switchgrass  

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

Solvent-Based Solvent-Based Biomass Pretreatment Breaks Highly Ordered Hydrogen Bonds in Cellulose Fibers of Switchgrass Noppadon Sathitsuksanoh, 1,2 Zhiguang Zhu, 1 Sungsool Wi, 3 Y.-H. Percival Zhang 1,2,4 1 Biological Systems Engineering Department, Virginia Polytechnic Institute and State University (Virginia Tech), 210-A Seitz Hall, Blacksburg, Virginia 24061; telephone: 540-231-7414, fax: 540-231-3199; e-mail: ypzhang@vt.edu 2 Institute for Critical Technology and Applied Science (ICTAS), Virginia Polytechnic Institute and State University, Blacksburg, Virginia 3 Chemistry Department, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 4 DOE BioEnergy Science Center (BESC), Oak Ridge, Tennessee Received 25 June 2010; revision received 23 August 2010; accepted 4 October 2010 Published online 21 October 2010 in Wiley Online Library (wileyonlinelibrary.com).

375

Argonne Breaks Ground on $34.5M MX Research Facility  

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

Stephenson Appointed ALD for Photon Sciences Stephenson Appointed ALD for Photon Sciences APS, Other DOE Labs Help Develop New Cancer Fighting Drug Paper on Fast Pharmaceuticals by APS Authors Featured in New Journal Art Scene Investigation: Picasso goes Nanotech Linda Young of APS Elected Vice Chair of DAMOP APS News Archives: 2012 | 2011 | 2010 | 2009 2008 | 2007 | 2006 | 2005 2004 | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed Argonne Breaks Ground on $34.5M MX Research Facility SEPTEMBER 15, 2011 Bookmark and Share Artist's rendering of the Advanced Protein Crystallization Facility (left in drawing). The Advanced Photon Source experiment hall is at right. The U.S. Department of Energy's (DOE's) Argonne National Laboratory broke ground on August 30, 2011, for a $34.5 million Advanced Protein

376

Single-Valued Hamiltonian via Legendre-Fenchel Transformation and Spontaneous Breaking of Time Translation Symmetry  

E-Print Network (OSTI)

Under conventional Legendre transformation, systems with a non-convex Lagrangian will result in a multi-valued Hamiltonian as a function of conjugate momentum. This causes problems such as non-unitary time evolution of quantum state and non-determined motion of classical particles, and is physically unacceptable. In this work, we propose a new construction of single-valued Hamiltonian by applying Legendre-Fenchel transformation, which is a mathematically rigorous generalization of conventional Legendre transformation, valid for non-convex Lagrangian systems, but not yet widely known to the physics community. With the new single-valued Hamiltonian, we study spontaneous breaking of time translation symmetry and derive its vacuum state.

Huan-Hang Chi; Hong-Jian He

2013-10-14T23:59:59.000Z

377

Wave-function entropy and dynamical-symmetry breaking in the interacting boson model  

E-Print Network (OSTI)

The degree of chaos in the Interacting Boson Model (IBM-1) is compared with what we call the "dynamical-symmetry content" of the system. The latter is represented by the information entropy of the eigenfunctions with respect to bases associated with dynamical symmetries of the IBM-1, and expresses thus the localization of actual eigenfunctions in these symmetry bases. The wave-function entropy is shown to be a sensitive tool for monitoring the processes of a single dynamical-symmetry breaking or transitions between two and more symmetries. For the IBM-1 hamiltonians studied here, the known features related to chaos, namely the dependence of chaotic measures on the hamiltonian parameters (position in the Casten triangle) and on the angular momentum, turn out to be correlated with the behaviour of the wave-function entropy. PACs 21.60.Fw; 05.45.+b

Pavel Cejnar; Jan Jolie

1998-02-25T23:59:59.000Z

378

Constraining Anomaly Mediated Supersymmetry Breaking Framework via Ongoing Muon g-2 Experiment at Brookhaven  

E-Print Network (OSTI)

The ongoing high precision E821 Brookhaven National Laboratory experiment on muon g-2 is promising to probe a theory involving supersymmetry. We have studied the constraints on the minimal Anomaly Mediated Supersymmetry Breaking (AMSB) model using the current data of muon g-2 from Brookhaven. A scenario of seeing no deviation from the Standard Model is also considered, within a $2\\sigma$ limit of the combined error from the Standard Model result and the Brookhaven predicted uncertainty level. The resulting constraint is found to be complementary to what one obtains from $b \\to s+ \\gamma$ bounds within the AMSB scenario, since only a definite sign of $\\mu$ is effectively probed via $b \\to s+ \\gamma$. A few relevant generic features of the model are also described for disallowed regions of parameter space.

Utpal Chattopadhyay; Dilip Kumar Ghosh; Sourov Roy

2000-06-05T23:59:59.000Z

379

Non-universal, Non-anomalous U(1)' in a Model with Anomaly Mediated SUSY Breaking  

E-Print Network (OSTI)

We construct a Minimum Supersymmetry Standard Model expanded by a non-anomalous family (NAF) U(1)'_{NAF} gauge symmetry. All gauge anomalies are cancelled with no additional exotics other than the three right-handed neutrinos. The FI D-terms associated with the U(1)'_{NAF} symmetry lead to additional positive contributions to slepton squared masses. In a RG invariant way, this thus solves the tachyonic slepton mass problem in Anomaly Mediated Supersymmetry Breaking. In addition, the U(1)'_{NAF} symmetry naturally gives rise to the fermion mass hierarchy and mixing angles, and determines the mass spectrum of the sparticles. Our model also provides a counter example to the previous claim that the only U(1)' that can give rise to realistic fermion mass hierarchy and mixing pattern must be anomalous.

Mu-Chun Chen; Jinrui Huang

2010-11-29T23:59:59.000Z

380

Collider signatures of low scale supersymmetry breaking: A Snowmass 2013 White Paper  

E-Print Network (OSTI)

We consider the possibility that supersymmetry is broken at a low scale, within one order of magnitude above the TeV scale. In such a case, the degrees of freedom associated with the spontaneous breaking of supersymmetry, the goldstino fermion and its scalar superpartner (the sgoldstino), can have significant interactions with the Standard Model particles and their superpartners. We discuss some characteristic processes, involving the goldstino and the sgoldstino, and the collider signatures they give rise to. These signatures involve scalar resonances in the di-photon, di-jet, di-boson and di-tau channels, the possible relation between these resonances and deviations in the Higgs couplings as well as exotic Higgs decays in the monophoton+MET and the four photon channels.

Emilian Dudas; Christoffer Petersson; Riccardo Torre

2013-09-04T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

The Green function and SU(3) breaking in K_{l3} decays  

E-Print Network (OSTI)

Using the 1/N_C expansion scheme and truncating the hadronic spectrum to the lowest-lying resonances, we match a meromorphic approximation to the Green function onto QCD by imposing the correct large-momentum falloff, both off-shell and on the relevant hadron mass shells. In this way we determine a number of chiral low-energy constants of O(p^6), in particular the ones governing SU(3) breaking in the K_{l3} vector form factor at zero momentum transfer. The main result of our matching procedure is that the known loop contributions largely dominate the corrections of O(p^6) to f_{+}(0). We discuss the implications of our final value f_{+}^{K^0 \\pi^-}(0)=0.984 \\pm 0.012 for the extraction of V_{us} from K_{l3} decays.

V. Cirigliano; G. Ecker; M. Eidemuller; R. Kaiser; A. Pich; J. Portoles

2005-03-11T23:59:59.000Z

382

Spatio-temporal evolution and breaking of double layers: A description using Lagrangian hydrodynamics  

Science Conference Proceedings (OSTI)

The nonlinear development and collapse (breaking) of double layers in the long scale length limit is well described by equations for the cold ion fluid with quasineutrality. It is shown that electron dynamics is responsible for giving an 'equation of state' with negative ratio of specific heats to this fluid. Introducing a transformation for the density variable, the governing equation for the transformed quantity in terms of Lagrange variables turns out exactly to be a linear partial differential equation. This equation has been analyzed in various limits of interest. Nonlinear development of double layers with a sinusoidal initial disturbance and collapse of double layers with an initial perturbation in the form of a density void are analytically investigated.

Kaw, Predhiman; Sengupta, Sudip; Singh Verma, Prabal [Institute for Plasma Research, Bhat, Gandhinagar 382 428 (India)

2012-10-15T23:59:59.000Z

383

Connected Green function approach to ground state symmetry breaking in $?^4_{1+1}$-theory  

E-Print Network (OSTI)

Using the cluster expansions for n-point Green functions we derive a closed set of dynamical equations of motion for connected equal-time Green functions by neglecting all connected functions higher than $4^{th}$ order for the $\\lambda \\Phi^4$-theory in $1+1$ dimensions. We apply the equations to the investigation of spontaneous ground state symmetry breaking, i.e. to the evaluation of the effective potential at temperature $T=0$. Within our momentum space discretization we obtain a second order phase transition (in agreement with the Simon-Griffith theorem) and a critical coupling of $\\lambda_{crit}/4m^2=2.446$ as compared to a first order phase transition and $\\lambda_{crit}/4m^2=2.568$ from the Gaussian effective potential approach.

J. M. Haeuser; W. Cassing; A. Peter; M. H. Thoma

1994-08-23T23:59:59.000Z

384

Silencing and recombination in yeast ribosomal DNA  

E-Print Network (OSTI)

A bioinformatic and laboratory investigation into S. cerevisiae's system for the maintenance and homogenization of rDNA. Eliminating mutations and heterogeneity in rDNA repeats is necessary evolutionarily, but harmful to ...

O'Kelly, Michael J. T

2008-01-01T23:59:59.000Z

385

Low-cost, Rapid DNA Sequencing Technique  

Sequencing DNA is crucial for future breakthroughs in biological and biomedical research. Until now, ... The nucleic acid strand transport

386

Amplification of chromosomal DNA in situ  

DOE Patents (OSTI)

Amplification of chromosomal DNA in situ to increase the amount of DNA associated with a chromosome or chromosome region is described. The amplification of chromosomal DNA in situ provides for the synthesis of Fluorescence in situ Hybridization (FISH) painting probes from single dissected chromosome fragments, the production of cDNA libraries from low copy mRNAs and improved in Comparative Genomic Hybridization (CGH) procedures.

Christian, Allen T. (Tracy, CA); Coleman, Matthew A. (Livermore, CA); Tucker, James D. (Livermore, CA)

2002-01-01T23:59:59.000Z

387

Topics and Techniques in Forensic DNA Analysis  

Science Conference Proceedings (OSTI)

... Topics and Techniques for Forensic DNA Analysis NYC OCME Dept of Forensic Biology ... NIST Human Identity Project Leader (1999-present) ...

2012-04-17T23:59:59.000Z

388

Quantum Dot Fluorescence Lifetime Engineering with DNA ...  

Science Conference Proceedings (OSTI)

Quantum Dot Fluorescence Lifetime Engineering with DNA Origami ... such as metal nanoparticles and semiconductor quantum dots – is challenging ...

389

Data hiding methods based upon DNA sequences  

Science Conference Proceedings (OSTI)

In this paper, three data hiding methods are proposed, based upon properties of DNA sequences. It is highlighted that DNA sequences possess some interesting properties which can be utilized to hide data. These three methods are: the Insertion Method, ... Keywords: Complementary pair, DNA, Data hiding, Data recovery

H. J. Shiu; K. L. Ng; J. F. Fang; R. C. T. Lee; C. H. Huang

2010-06-01T23:59:59.000Z

390

Magnetic tweezers to study DNA motors  

E-Print Network (OSTI)

Magnetic tweezers to study DNA motors Maria Mañosas Ritort lab UB Barcelona Croquette-Bensimon lab ENS France #12;· Introduction to MT (magnetic tweezers) · Applications: 1. Tracking DNA motors: (i) Helicases (ii) Annealing motor 2. Studying a multiprotein system: DNA replication Outline #12;· Atomic force

Ritort, Felix

391

Probe and method for DNA detection  

SciTech Connect

A hybridization probe containing two linear strands of DNA lights up upon hybridization to a target DNA using silver nanoclusters that have been templated onto one of the DNA strands. Hybridization induces proximity between the nanoclusters on one strand and an overhang on the other strand, which results in enhanced fluorescence emission from the nanoclusters.

Yeh, Hsin-Chih; Werner, James Henry; Sharma, Jaswinder Kumar; Martinez, Jennifer Suzanne

2013-07-02T23:59:59.000Z

392

Proteomic profiling revealed the functional networks associated with mitotic catastrophe of HepG2 hepatoma cells induced by 6-bromine-5-hydroxy-4-methoxybenzaldehyde  

Science Conference Proceedings (OSTI)

Mitotic catastrophe, a form of cell death resulting from abnormal mitosis, is a cytotoxic death pathway as well as an appealing mechanistic strategy for the development of anti-cancer drugs. In this study, 6-bromine-5-hydroxy-4-methoxybenzaldehyde was demonstrated to induce DNA double-strand break, multipolar spindles, sustain mitotic arrest and generate multinucleated cells, all of which indicate mitotic catastrophe, in human hepatoma HepG2 cells. We used proteomic profiling to identify the differentially expressed proteins underlying mitotic catastrophe. A total of 137 differentially expressed proteins (76 upregulated and 61 downregulated proteins) were identified. Some of the changed proteins have previously been associated with mitotic catastrophe, such as DNA-PKcs, FoxM1, RCC1, cyclin E, PLK1-pT210, 14-3-3{sigma} and HSP70. Multiple isoforms of 14-3-3, heat-shock proteins and tubulin were upregulated. Analysis of functional significance revealed that the 14-3-3-mediated signaling network was the most significantly enriched for the differentially expressed proteins. The modulated proteins were found to be involved in macromolecule complex assembly, cell death, cell cycle, chromatin remodeling and DNA repair, tubulin and cytoskeletal organization. These findings revealed the overall molecular events and functional signaling networks associated with spindle disruption and mitotic catastrophe. - Graphical abstract: Display Omitted Research highlights: > 6-bromoisovanillin induced spindle disruption and sustained mitotic arrest, consequently resulted in mitotic catastrophe. > Proteomic profiling identified 137 differentially expressed proteins associated mitotic catastrophe. > The 14-3-3-mediated signaling network was the most significantly enriched for the altered proteins. > The macromolecule complex assembly, cell cycle, chromatin remodeling and DNA repair, tubulin organization were also shown involved in mitotic catastrophe.

Zhang Bo [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Huang Bo [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); School of Public Health, University of South China, Hengyang, Hunan 421001 (China); Guan Hua; Zhang Shimeng; Xu Qinzhi [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); He Xingpeng [School of Public Health, University of South China, Hengyang, Hunan 421001 (China); Liu Xiaodan; Wang Yu; Shang Zengfu [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Zhou Pingkun, E-mail: zhoupk@nic.bmi.ac.cn [Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); School of Public Health, University of South China, Hengyang, Hunan 421001 (China)

2011-05-01T23:59:59.000Z

393

The Landsat Scale Break in Stratocumulus as a Three-Dimensional Radiative Transfer Effect: Implications for Cloud Remote Sensing  

Science Conference Proceedings (OSTI)

Several studies have uncovered a break in the scaling properties of Landsat cloud scenes at nonabsorbing wavelengths. For scales greater than 200–400 m, the wavenumber spectrum is approximately power law in k?5/3, but from there down to the ...

Anthony Davis; Alexander Marshak; Robert Cahalan; Warren Wiscombe

1997-01-01T23:59:59.000Z

394

The Effect of Breaking Waves on a Coupled Model of Wind and Ocean Surface Waves. Part I: Mature Seas  

Science Conference Proceedings (OSTI)

This is the first of a two-part investigation of a coupled wind and wave model that includes the enhanced form drag of breaking waves. In Part I here the model is developed and applied to mature seas. Part II explores the solutions in a wide ...

Tobias Kukulka; Tetsu Hara

2008-10-01T23:59:59.000Z

395

TabletopAccelerator Breaks`Cold Fusion'Jinx ButWon'tYield Energy,Physicists Say  

E-Print Network (OSTI)

TabletopAccelerator Breaks`Cold Fusion'Jinx ButWon'tYield Energy,Physicists Say A crystal with a strange property is at the heart of a clever method for inducing nuclear fusion in a tabletop-sized device-rays for medical therapies. Although the field of room-temperature fusion is littered with scandals and dubious

396

A Model of the Air–Sea Momentum Flux and Breaking-Wave Distribution for Strongly Forced Wind Waves  

Science Conference Proceedings (OSTI)

Under high-wind conditions, breaking surface waves likely play an important role in the air–sea momentum flux. A coupled wind–wave model is developed based on the assumption that in the equilibrium range of surface wave spectra the wind stress is ...

Tobias Kukulka; Tetsu Hara; Stephen E. Belcher

2007-07-01T23:59:59.000Z

397

On the Semidiurnal Internal Tide at a Shelf-Break Region on the Australian North West Shelf  

Science Conference Proceedings (OSTI)

The properties of the semidiurnal internal tide, in the region of the shelf-break, at a location on the Australian North West Shelf are discussed. Information is derived from an analysis of thermistor chain and current meter data, collected over ...

Peter E. Holloway

1984-11-01T23:59:59.000Z

398

Water-hydroxyl phases on an open metal surface: breaking the ice rules Matthew Forster,a  

E-Print Network (OSTI)

Water-hydroxyl phases on an open metal surface: breaking the ice rules Matthew Forster,a Rasmita hexagonal c(2 Ã? 2) 2H2O:1OH network. None of these phases obey the conventional `ice rules', instead catalyzed redox reactions, yet establishing the phase diagram for water/hydroxyl adsorption on metal

Alavi, Ali

399

JET BREAKS IN SHORT GAMMA-RAY BURSTS. I. THE UNCOLLIMATED AFTERGLOW OF GRB 050724 Dirk Grupe,1  

E-Print Network (OSTI)

JET BREAKS IN SHORT GAMMA-RAY BURSTS. I. THE UNCOLLIMATED AFTERGLOW OF GRB 050724 Dirk Grupe,1 the results of the Chandra observations of the Swift-discovered short gamma-ray burst GRB 050724. Chandra corrected energy of GRB 050724 is at least 4 ; 1049 ergs. Subject headinggs: gamma rays: bursts -- X-rays

Zhang, Bing

400

Further study of an approach to the unification of gauge symmetries in theories with dynamical symmetry breaking  

Science Conference Proceedings (OSTI)

We extend to larger unification groups an earlier study exploring the possibility of unification of gauge symmetries in theories with dynamical symmetry breaking. Based on our results, we comment on the outlook for models that seek to achieve this type of unification.

Chen Ning; Shrock, Robert [C.N. Yang Institute for Theoretical Physics, Stony Brook University, Stony Brook, New York 11794 (United States)

2008-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

RELAP5/MOD3 assessment using the Semiscale 50% Feed Line Break test S-FS-11  

SciTech Connect

The RELAP5/MOD3 5m5 code was assessed using the 1/1705 volume scaled Semiscale 50% Feed Line Break (FLB) test S-FS-11. Test S-FS-11 was designed in three phases: (a) blowdown phase, (b) stabilization phase, and (c) refill phase. The first objective was to assess the code applicability to 50% FLB situation, the second was to evaluate the FSAR conservatisms regarding SG heat transfer degradation, steam line check valve failure, break flow state, and peak primary system pressure, and the third was to validate the EOP effectiveness. The code was able to simulate the major T/H parameters except for the two-phase break flow and the secondary convective heat transfer rate. The two-phase break flow had still deficiencies. The current boiling heat transfer rate was developed from the data for flow inside of a heated tube, not for flow around heated tubes in a tube bundle. Results indicated that the assumption of 100% heat transfer until the liquid inventory depletion was not conservative, the failed affected steam generator main steam line check valve assumption was not either conservative, the measured break flow experienced all types of flow conditions, the relative proximity to the 110% design pressure limit was conservative. The automatic actions during the blowdown phase were effective in mitigating the consequences. The stabilization operation performed by operator actions were effective to permit natural circulation cooldown and depressurization. The voided secondary refill operations also verified the effectiveness of the operations while recovering the inventory in a voided steam generator.

Lee, E.J.; Chung, B.D.; Kim, H.J. [Korea Inst. of Nuclear Safety, Taejon (Korea, Republic of)

1993-06-01T23:59:59.000Z

402

Microfluidic DNA sample preparation method and device  

DOE Patents (OSTI)

Manipulation of DNA molecules in solution has become an essential aspect of genetic analyses used for biomedical assays, the identification of hazardous bacterial agents, and in decoding the human genome. Currently, most of the steps involved in preparing a DNA sample for analysis are performed manually and are time, labor, and equipment intensive. These steps include extraction of the DNA from spores or cells, separation of the DNA from other particles and molecules in the solution (e.g. dust, smoke, cell/spore debris, and proteins), and separation of the DNA itself into strands of specific lengths. Dielectrophoresis (DEP), a phenomenon whereby polarizable particles move in response to a gradient in electric field, can be used to manipulate and separate DNA in an automated fashion, considerably reducing the time and expense involved in DNA analyses, as well as allowing for the miniaturization of DNA analysis instruments. These applications include direct transport of DNA, trapping of DNA to allow for its separation from other particles or molecules in the solution, and the separation of DNA into strands of varying lengths.

Krulevitch, Peter A. (Pleasanton, CA); Miles, Robin R. (Danville, CA); Wang, Xiao-Bo (San Diego, CA); Mariella, Raymond P. (Danville, CA); Gascoyne, Peter R. C. (Bellaire, TX); Balch, Joseph W. (Livermore, CA)

2002-01-01T23:59:59.000Z

403

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.

404

Fleet DNA Project (Fact Sheet)  

SciTech Connect

The Fleet DNA Project - designed by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in partnership with Oak Ridge National Laboratory - aims to accelerate the evolution of advanced vehicle development and support the strategic deployment of market-ready technologies that reduce costs, fuel consumption, and emissions. At the heart of the Fleet DNA Project is a clearinghouse of medium- and heavy-duty commercial fleet transportation data for optimizing the design of advanced vehicle technologies or for selecting a given technology to invest in. An easy-to-access online database will help vehicle manufacturers and fleets understand the broad operational range for many of today's commercial vehicle vocations.

Not Available

2012-10-01T23:59:59.000Z

405

Channel plate for DNA sequencing  

DOE Patents (OSTI)

This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface.

Douthart, Richard J. (Richland, WA); Crowell, Shannon L. (Eltopia, WA)

1998-01-01T23:59:59.000Z

406

Channel plate for DNA sequencing  

DOE Patents (OSTI)

This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface. 15 figs.

Douthart, R.J.; Crowell, S.L.

1998-01-13T23:59:59.000Z

407

Low-Energy Supersymmetry Breaking from String Flux Compactifications: Benchmark Scenarios  

E-Print Network (OSTI)

Soft supersymmetry breaking terms were recently derived for type IIB string flux compactifications with all moduli stabilised. Depending on the choice of the discrete input parameters of the compactification such as fluxes and ranks of hidden gauge groups, the string scale was found to have any value between the TeV and GUT scales. We study the phenomenological implications of these compactifications at low energy. Three realistic scenarios can be identified depending on whether the Standard Model lies on D3 or D7 branes and on the value of the string scale. For the MSSM on D7 branes and the string scale between 10^12 GeV and 10^17 GeV we find that the LSP is a neutralino, while for lower scales it is the stop. At the GUT scale the results of the fluxed MSSM are reproduced, but now with all moduli stabilised. For the MSSM on D3 branes we identify two realistic scenarios. The first one corresponds to an intermediate string scale version of split supersymmetry. The second is a stringy mSUGRA scenario. This requires tuning of the flux parameters to obtain the GUT scale. Phenomenological constraints from dark matter, (g-2)_mu and BR(b->s gamma) are considered for the three scenarios. We provide benchmark points with the MSSM spectrum, making the models suitable for a detailed phenomenological analysis.

Benjamin C. Allanach; Fernando Quevedo; Kerim Suruliz

2005-12-06T23:59:59.000Z

408

Double symmetry breaking of solitons in one-dimensional virtual photonic crystals  

SciTech Connect

We demonstrate that spatial solitons undergo two consecutive spontaneous symmetry breakings (SSBs), with the increase of the total power, in nonlinear photonic crystals (PhCs) built as arrays of alternating linear and nonlinear stripes, in the case when the maxima of the effective refractive index coincide with the minima of the self-focusing coefficient and vice versa (i.e., the corresponding linear and nonlinear periodic potentials are in competition). This setting may be induced, as a virtual PhC, by means of the electromagnetically induced-transparency (EIT) technique, in a uniform optical medium. It may also be realized as a Bose-Einstein condensate (BEC) subject to the action of the combined periodic optical potential and periodically modulated Feshbach resonance. The first SSB happens at the center of a linear stripe, pushing a broad low-power soliton into an adjacent nonlinear stripe and gradually suppressing side peaks in the soliton's shape. Then the soliton restores its symmetry, being pinned to the midpoint of the nonlinear stripe. The second SSB occurs at higher powers, pushing the narrow soliton off the center of the nonlinear channel, while the soliton keeps its internal symmetry. The results are obtained by means of numerical and analytical methods. They may be employed to control switching of light beams by means of the varying power.

Li Yongyao [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275 (China); Department of Applied Physics, South China Agricultural University, Guangzhou 510642 (China); Malomed, Boris A. [Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv IL-69978 (Israel); ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, E-08860 Castelldefels (Barcelona) (Spain); Feng Mingneng; Zhou Jianying [State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275 (China)

2011-05-15T23:59:59.000Z

409

Spontaneous breaking of conformal invariance, solitons and gravitational waves in theories of conformally invariant gravitation  

E-Print Network (OSTI)

We study conformal gravity as an alternative theory of gravitation. For conformal gravity to be phenomenologically viable requires that the conformal symmetry is not manifest at the energy scales of the other known physical forces. Hence we require a mechanism for the spontaneous breaking of conformal invariance. In this paper we study the possibility that conformal invariance is spontaneously broken due to interactions with conformally coupled matter fields. The vacuum of the theory admits conformally non-invariant solutions corresponding to maximally symmetric space-times and variants thereof. These are either de Sitter space-time or anti-de Sitter space-time in the full four space-time dimensions or in a lower dimensional sub-space. We consider in particular normalizable, linearized gravitational perturbations around the anti-de Sitter background. Exploiting the conformal flatness of this space-time, we show to second order, that these gravitational fluctuations, that are taken to be fourier decomposable, carry zero energy-momentum. This squares well with the theorem that asymptotically flat space-times conformal gravity contain zero energy and momentum \\cite{bhs}. We also show the possibility of domain wall solitons interpolating between the ground states of spontaneously broken conformal symmetry that we have found. These solitons necessarily require the vanishing of the scalar field, repudiating the recent suggestion \\cite{f} that the conformal symmetry could be quarantined to a sterile sector of the theory by choosing an appropriate field redefinition.

Jihene Bouchami; M. B. Paranjape

2007-10-29T23:59:59.000Z

410

Spontaneous onset of magnetic reconnection in toroidal plasma caused by breaking of 2D symmetry  

SciTech Connect

Magnetic reconnection is studied in the collisionless limit at the Versatile Toroidal Facility (VTF) at MIT. Two distinct magnetic configurations are applied in the experiments; an open magnetic cusp and a closed cusp. In the open cusp configurations, the field lines intersect the the vacuum vessel walls and here axisymmetric oscillatory reconnection is observed. Meanwhile, in the closed cusp configuration, where the field lines are confined inside the experiment, the coupling between global modes and a current sheet leads to powerful bursts of 3D spontaneous reconnection. These spontaneous events start at one toroidal location, and then propagate around the toroidal direction at the Alfven speed (calculated with the strength of the dominant guide field). The three dimensional measurements include the detailed time evolution of the plasma density, current density, the magnetic flux function, the electrostatic potential, and the reconnection rate. The vastly different plasma behavior in the two configurations can be described using a simple theoretical framework, linking together the interdependencies of the reconnection rate, the in-plane electrostatic potential, and the parallel electron currents. We find that it is the breaking of toroidal symmetry by the global mode that allows for a localized disruption of the x-line current and hereby facilitates the onset of spontaneous reconnection.

Egedal, Jan; Katz, Noam; Bonde, Jeff; Fox, Will; Le, Ari; Porkolab, Miklos; Vrublevskis, Arturs [Department of Physics/Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2011-11-15T23:59:59.000Z

411

Octahedral Symmetry with Geometrical Breaking: New Prediction for Neutrino Mixing Angle theta_{13} and CP Violation  

E-Print Network (OSTI)

We propose octahedral group O_h as the family symmetry of neutrino-lepton sector, with subgroups Z_2(mu-tau) x Z_2(solar) and Z_4^l as the residual symmetries of neutrinos and charged leptons, respectively. We find that O_h is a minimal group which contains the subgroups Z_2(mu-tau) x Z_2(solar) and Z_4^l for realizing the bimaximal mixings theta_{23} = theta_{12} = 45^o. We present geometric interpretations of O_h and its residual symmetries, and further construct a natural geometrical breaking of Z_4^l. Our theory makes truly simple new predictions of a relatively large reactor angle, theta_{13} = 45^o - theta_{12} = 7.9^o - 14.0^o (3 sigma), the maximal atmospheric angle theta_{23} = 45^o, and the maximal Dirac CP violation delta_D = +-90^o. These agree well with the current neutrino data, and will be further probed by the on-going and upcoming oscillation experiments.

He, Hong-Jian

2012-01-01T23:59:59.000Z

412

Octahedral Symmetry with Geometrical Breaking: New Prediction for Neutrino Mixing Angle theta_{13} and CP Violation  

E-Print Network (OSTI)

We propose octahedral group O_h as the family symmetry of neutrino-lepton sector. We find that O_h contains subgroups Z_2(mu-tau) x Z_2(solar) and Z_4^l for realizing the bimaximal (BM) mixings, theta_{23} = theta_{12} = 45^o and theta_{13}=0^o, where Z_2(mu-tau) x Z_2(solar) and Z_4^l serve as the residual symmetries of neutrinos and charged leptons, respectively. We present geometric interpretations of BM mixing in the octahedron, and construct natural geometrical breaking of Z_4^l, leading to nontrivial deviations from the BM mixings. Our theory makes truly simple predictions of a relatively large reactor angle, theta_{13} = 45^o - theta_{12} = 7.5^o - 13.7^o (3 sigma), the nearly maximal atmospheric angle and the approximate maximal Dirac CP violation. These agree well with the current neutrino data, and will be further probed by the on-going and upcoming oscillation experiments.

Hong-Jian He; Xun-Jie Xu

2012-03-13T23:59:59.000Z

413

PT-symmetric sinusoidal optical lattices at the symmetry-breaking threshold  

SciTech Connect

The PT-symmetric potential V{sub 0}[cos(2{pi}x/a)+i{lambda}sin(2{pi}x/a)] has a completely real spectrum for {lambda}{<=}1 and begins to develop complex eigenvalues for {lambda}>1. At the symmetry-breaking threshold {lambda}=1 some of the eigenvectors become degenerate, giving rise to a Jordan-block structure for each degenerate eigenvector. In general this is expected to result in a secular growth in the amplitude of the wave. However, it has been shown in a recent paper by Longhi, by numerical simulation and by the use of perturbation theory, that for a broad initial wave packet this growth is suppressed, and instead a saturation leading to a constant maximum amplitude is observed. We revisit this problem by explicitly constructing the Bloch wave functions and the associated Jordan functions and using the method of stationary states to find the dependence on the longitudinal distance z for a variety of different initial wave packets. This allows us to show in detail how the saturation of the linear growth arises from the close connection between the contributions of the Jordan functions and those of the neighboring Bloch waves.

Graefe, Eva-Maria [Mathematics Department, Imperial College, London SW7 2BZ (United Kingdom); Jones, H. F. [Physics Department, Imperial College, London SW7 2BZ (United Kingdom)

2011-07-15T23:59:59.000Z

414

Electroweak symmetry breaking studies at the pp colliders of the 1990's and beyond  

SciTech Connect

Within the conventional framework of a spontaneously broken gauge theory, general principles establish that the electroweak symmetry is broken by a new force that may be weak with associated new quanta below 1 TeV or strong with quanta above 1 TeV. The SSC parameters, ..sqrt..s = 40 TeV and L = 10/sup 33/ cm/sup /minus/2/s/sup /minus/1/, define a minimal facility with assured capability to observe the signals of symmetry breaking by a strong force above 1 TeV. Foreseeable luminosity upgrades would not be able to compensate a much lower collider energy for these physics signals. If the strong WW scattering signal were seen at the SSC in the 1990's it would provide a clear imperative for a collider with the physics reach of the ELOISATRON to begin detailed studies of the new force and quanta early in the next century. 35 refs., 7 figs., 4 tabs.

Chanowitz, M.S.

1989-03-08T23:59:59.000Z

415

Is Dark Matter Heavy Because of Electroweak Symmetry Breaking? Revisiting Heavy Neutrinos  

E-Print Network (OSTI)

A simple and well-motivated explanation for the origin of dark matter is that it consists of thermal relic particles that get their mass entirely through electroweak symmetry breaking. The simplest models implementing this possibility predict a dark matter candidate that consists of a mixture of two Dirac neutrinos with opposite isospin, and so has suppressed coupling to the Z. These models predict dark matter masses of m_{DM}~45 GeV or m_{DM}~90-95 GeV and WIMP-neutron spin-independent cross sections \\sigma_{WIMP-n}~10^{-6}-10^{-8} pb. Current direct dark matter searches are probing a portion of the parameter space of these models while future experiments sensitive to \\sigma_{WIMP-n}~10^{-8} pb will probe the remainder. An enhancement of the galactic halo gamma ray and positron flux coming from annihilations of these particles is also expected across the ~1-100 GeV range. The framework further suggests an environmental explanation of the hierarchy between the weak and Planck scales and of the small value of the cosmological constant relative to the weak scale.

Philip C. Schuster; Natalia Toro

2005-06-08T23:59:59.000Z

416

Proceedings of the seminar on leak before break in reactor piping and vessels  

SciTech Connect

The objective of the seminar was to present the current state of the art in Leak-Before-Break (LBB) methodology development, validation, and application in an international forum. With particular emphasis on industrial applications and regulatory policies, the seminar provided an opportunity to compare approaches, experiences, and codifications developed by different countries. The seminar was organized into four topic areas: status of LBB applications; technical issues in LBB methodology; complementary requirements (leak detection and inspection); LBB assessment and margins. As a result of this seminar, an improved understanding of LBB gained through sharing of different viewpoints from different countries, permits consideration of: simplified pipe support design and possible elimination of loss-of-coolant-accident (LOCA) mechanical consequences for specific cases; defense-in-depth type of applications without support modifications; support of safety cases for plants designed without the LOCA hypothesis. In support of these activities, better estimates of the limits to the LBB approach should follow, as well as an improvement in codifying methodologies. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.

Faidy, C. [ed.] [Electricite de France, Villeurbanne (France); Gilles, P. [ed.] [Framatome, Paris (France)

1997-04-01T23:59:59.000Z

417

ATM-Dependent Hyper-Radiosensitivity in Mammalian Cells Irradiated by Heavy Ions  

SciTech Connect

Purpose: Low-dose hyper-radiosensitivity (HRS) and the later appearing radioresistance (termed induced radioresistance [IRR]) was mainly studied in low linear energy transfer (LET) radiation with survival observation. The aim of this study was to find out whether equivalent hypersensitivity occurred in high LET radiation, and the roles of ataxia telangiectasia mutated (ATM) kinase. Methods and Materials: Survival and mutation were measured by clonogenic assay and HPRT mutation assay. ATM Ser1981 activation was detected by Western blotting and immunofluorescent staining. Pretreatment of specific ATM inhibitor (10 {mu}M KU55933) and activator (20 {mu}g/mL chloroquine) before carbon radiation were adopted to explore the involvement of ATM. The roles of ATM were also investigated in its G2/M checkpoint function with histone H3 phosphorylation analysis and flow cytometric assay, and DNA double strand break (DSB) repair function measured using {gamma}-H2AX foci assay. Results: HRS/IRR was observed with survival and mutation in normal human skin fibroblast cells by carbon ions, while impaired in cells with intrinsic ATM deficiency or normal cells modified with specific ATM activator or inhibitor before irradiation. The dose-response pattern of ATM kinase activation was concordant with the transition from HRS to IRR. The ATM-dependent 'early' G2 checkpoint arrest and DNA DSB repair efficiency could explain the difference between HRS and IRR. Conclusions: These data demonstrate that the HRS/IRR by carbon ion radiation is an ATM-dependent phenomenon in the cellular response to DNA damage.

Xue Lian [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou (China); Yu Dong [Tumor Endocrinology Project, National Cancer Center Research Institute, Chuo-ku, Tokyo (Japan)], E-mail: ydong@ncc.go.jp; Furusawa, Yoshiya [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba-shi (Japan); Cao Jianping [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou (China); Okayasu, Ryuichi [Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba-shi (Japan); Fan Saijun [School of Radiation Medicine and Public Health, Medical College of Soochow University, Suzhou (China)

2009-09-01T23:59:59.000Z

418

Enhancing the DNA Patent Database  

Science Conference Proceedings (OSTI)

Final Report on Award No. DE-FG0201ER63171 Principal Investigator: LeRoy B. Walters February 18, 2008 This project successfully completed its goal of surveying and reporting on the DNA patenting and licensing policies at 30 major U.S. academic institutions. The report of survey results was published in the January 2006 issue of Nature Biotechnology under the title “The Licensing of DNA Patents by US Academic Institutions: An Empirical Survey.” Lori Pressman was the lead author on this feature article. A PDF reprint of the article will be submitted to our Program Officer under separate cover. The project team has continued to update the DNA Patent Database on a weekly basis since the conclusion of the project. The database can be accessed at dnapatents.georgetown.edu. This database provides a valuable research tool for academic researchers, policymakers, and citizens. A report entitled Reaping the Benefits of Genomic and Proteomic Research: Intellectual Property Rights, Innovation, and Public Health was published in 2006 by the Committee on Intellectual Property Rights in Genomic and Protein Research and Innovation, Board on Science, Technology, and Economic Policy at the National Academies. The report was edited by Stephen A. Merrill and Anne-Marie Mazza. This report employed and then adapted the methodology developed by our research project and quoted our findings at several points. (The full report can be viewed online at the following URL: http://www.nap.edu/openbook.php?record_id=11487&page=R1). My colleagues and I are grateful for the research support of the ELSI program at the U.S. Department of Energy.

Walters, LeRoy B.

2008-02-18T23:59:59.000Z

419

Universal breaking point asymptotic for energy spectrum of Riemann waves in weakly nonlinear non-dispersive media  

E-Print Network (OSTI)

In this Letter we study the form of the energy spectrum of Riemann waves in weakly nonlinear non-dispersive media. For quadratic and cubic nonlinearity we demonstrate that the deformation of an Riemann wave over time yields an exponential energy spectrum which turns into power law asymptotic with the slope being approximately -8/3 at the last stage of evolution before breaking. We argue, that this is the universal asymptotic behaviour of Riemann waves in any nonlinear non-dispersive medium at the point of breaking. The results reported in this Letter can be used in various non-dispersive media, e.g. magneto-hydro dynamics, physical oceanography, nonlinear acoustics.

Kartashova, Elena

2013-01-01T23:59:59.000Z

420

DNA-guided nanoparticle assemblies  

DOE Patents (OSTI)

In some embodiments, DNA-capped nanoparticles are used to define a degree of crystalline order in assemblies thereof. In some embodiments, thermodynamically reversible and stable body-centered cubic (bcc) structures, with particles occupying <.about.10% of the unit cell, are formed. Designs and pathways amenable to the crystallization of particle assemblies are identified. In some embodiments, a plasmonic crystal is provided. In some aspects, a method for controlling the properties of particle assemblages is provided. In some embodiments a catalyst is formed from nanoparticles linked by nucleic acid sequences and forming an open crystal structure with catalytically active agents attached to the crystal on its surface or in interstices.

Gang, Oleg; Nykypanchuk, Dmytro; Maye, Mathew; van der Lelie, Daniel

2013-07-16T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Immunoglobulin motif DNA recognition and  

E-Print Network (OSTI)

binding domains of NF-kB, NFAT1, p53 and the STAT proteins. NMR spectroscopy of a 43.6 kD RD­b­DNA ternary for NF-kB3-4, the nuclear factor of acti- vated T-cells NFAT1 (refs 5,6), STAT1 (ref. 7) and STAT3b8 72 and Ser 73. In con- trast, the N-terminus of NF-kB3-4 and NFAT1 (refs 5, 6) loops around

Sali, Andrej

422

DNA Directed Assembly Probe for Detecting DNA-Protein Interaction in Microarray Format  

E-Print Network (OSTI)

Quantifying DNA-protein interaction using DNA microarrays are gaining increasing attention due to their ability to profile specificity of interactions in a high-throughput manner. This paper describes a new approach that ...

Ng, Jin Kiat

423

Experimental Study on Kinematics and Dynamics of Breaking Waves in Deep Water  

E-Print Network (OSTI)

A new measurement technique called fiber optic reflectometer (FOR) was developed to investigate multiphase flows. The principle and setup of the FOR technique were introduced and applied to various experiments. Based on the coherently mixed signal between the Fresnel reflection off the fiber-liquid interface and the scattered signal off the object, such as a gas bubble, and a solid particle, this single probe technique is capable of simultaneously measuring the velocity of the object with a high accuracy and the phase of the fluid. In addition, bubble diameter, velocity, and void fraction were measured directly. By means of a simple modification of the FOR technique, solute concentration and refractive index change were measured with a greatly improved accuracy. This modified technique was used for measuring of a NaCl concentration in deionized water to validate a new normalization technique. In the second part of this thesis, a plunging breaking wave in deep water has been studied. Using the wave focusing method, a strong plunging breaker was generated with accuracy in the deep water condition in a two-dimensional wave tank. It was possible to describe the breaking process in detail using a high speed camera with a frame rate of 500 or 1000 fps. Four kinds of experimental techniques were employed or developed to investigate the plunging breaker. Bubble image velocimetry (BIV) and particle image velocimetry (PIV) were used to measure the velocity fields. The velocity fields of the highly aerated region were obtained from the BIV measurements. In addition, the modified PIV technique is capable of measuring the velocities in the entire flow field including the aerated region. Mean and turbulent properties were obtained by the ensemble average. The mean velocity, mean vorticity, and mean kinetic energy were examined over the entire flow field. In addition, the Reynolds stresses and turbulent kinetic energy were calculated with high temporal and spatial resolutions. Free surface elevation was obtained from wave gauge measurements. BIV and PIV images were also used to obtain the free surface elevation and the boundary of the aerated region for more accurate results. The FOR technique was used to obtain the void ratio at each splash-up region. Compressibility of the plunging breaker was considered. Mass flux, momentum flux, kinetic energy, and Reynolds stresses at each FOR station were recalculated using the void ratio obtained from the FOR measurements. All terms at the first splash-up region were highly overestimated more than 100 percent unless the void ratio was applied to the calculation of fluxes and energies. Compared with the fully developed first splash-up region, the overestimation at the second and third splash-up was less significant. However, most terms were overestimated by 20~30 percent when the void ratio was not considered.

Lim, Ho Joon

2010-08-01T23:59:59.000Z

424

DNA sequencing using fluorescence background electroblotting membrane  

DOE Patents (OSTI)

A method for the multiplex sequencing on DNA is disclosed which comprises the electroblotting or specific base terminated DNA fragments, which have been resolved by gel electrophoresis, onto the surface of a neutral non-aromatic polymeric microporous membrane exhibiting low background fluorescence which has been surface modified to contain amino groups. Polypropylene membranes are preferably and the introduction of amino groups is accomplished by subjecting the membrane to radio or microwave frequency plasma discharge in the presence of an aminating agent, preferably ammonia. The membrane, containing physically adsorbed DNA fragments on its surface after the electroblotting, is then treated with crosslinking means such as UV radiation or a glutaraldehyde spray to chemically bind the DNA fragments to the membrane through said smino groups contained on the surface thereof. The DNA fragments chemically bound to the membrane are subjected to hybridization probing with a tagged probe specific to the sequence of the DNA fragments. The tagging may be by either fluorophores or radioisotopes. The tagged probes hybridized to said target DNA fragments are detected and read by laser induced fluorescence detection or autoradiograms. The use of aminated low fluorescent background membranes allows the use of fluorescent detection and reading even when the available amount of DNA to be sequenced is small. The DNA bound to the membrances may be reprobed numerous times.

Caldwell, Karin D. (Salt Lake City, UT); Chu, Tun-Jen (Salt Lake City, UT); Pitt, William G. (Orem, UT)

1992-01-01T23:59:59.000Z

425

DNA sequencing using fluorescence background electroblotting membrane  

DOE Patents (OSTI)

A method for the multiplex sequencing on DNA is disclosed which comprises the electroblotting or specific base terminated DNA fragments, which have been resolved by gel electrophoresis, onto the surface of a neutral non-aromatic polymeric microporous membrane exhibiting low background fluorescence which has been surface modified to contain amino groups. Polypropylene membranes are preferably and the introduction of amino groups is accomplished by subjecting the membrane to radio or microwave frequency plasma discharge in the presence of an aminating agent, preferably ammonia. The membrane, containing physically adsorbed DNA fragments on its surface after the electroblotting, is then treated with crosslinking means such as UV radiation or a glutaraldehyde spray to chemically bind the DNA fragments to the membrane through amino groups contained on the surface. The DNA fragments chemically bound to the membrane are subjected to hybridization probing with a tagged probe specific to the sequence of the DNA fragments. The tagging may be by either fluorophores or radioisotopes. The tagged probes hybridized to the target DNA fragments are detected and read by laser induced fluorescence detection or autoradiograms. The use of aminated low fluorescent background membranes allows the use of fluorescent detection and reading even when the available amount of DNA to be sequenced is small. The DNA bound to the membranes may be reprobed numerous times. No Drawings

Caldwell, K.D.; Chu, T.J.; Pitt, W.G.

1992-05-12T23:59:59.000Z

426

Precision Biochemistry Tracks DNA Damage in Fish  

Science Conference Proceedings (OSTI)

... Like coal-mine canaries, fish DNA can serve as a measure of the biological impact of water and sediment pollution—or pollution clean-up. ...

2012-10-17T23:59:59.000Z

427

Topics in Forensic DNA Analysis & Interpretation  

Science Conference Proceedings (OSTI)

... Experience • University of Virginia/FBI Laboratory (1992-1995) – Work ... Most forensic DNA laboratories follow PCR ... for the polymer) • If a lab is not ...

2011-03-24T23:59:59.000Z

428

Available Technologies: Highly Selective, Highly Efficient DNA ...  

... applications where extraction of minute amounts of DNA plays a critical role, such as in basic and applied molecular biology research, bioforensics, ...

429

Overview of DNA Programs at NIST  

Science Conference Proceedings (OSTI)

... during the PCR amplification process – This is highly affected by DNA quantity and quality ... PCR inhibitors present in the sample may reduce PCR ...

2013-04-10T23:59:59.000Z

430

Effect of $U_A(1)$ Breaking on Chiral Phase Structure and Pion Superfluidity at Finite Isospin Chemical Potential  

E-Print Network (OSTI)

We investigate the isospin chemical potential effect in the frame of SU(2) Nambu-Jona-Lasinio model. When the isospin chemical potential is less than the vacuum pion mass, the phase structure with two chiral phase transition lines does not happen due to $U_A(1)$ breaking of QCD. When the isospin chemical potential is larger than the vacuum pion mass, the ground state of the system is a Bose-Einstein condensate of charged pions.

Lianyi He; Meng Jin; Pengfei Zhuang

2005-03-24T23:59:59.000Z

431

Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network  

Science Conference Proceedings (OSTI)

We analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative borderline between superadditivities of bipartite and multipartite systems.

Grudka, Andrzej [Faculty of Physics, Adam Mickiewicz University, PL-61-614 Poznan (Poland); National Quantum Information Centre of Gdansk, PL-81-824 Sopot (Poland); Horodecki, Pawel [National Quantum Information Centre of Gdansk, PL-81-824 Sopot (Poland); Faculty of Applied Physics and Mathematics, Technical University of Gdansk, PL-80-952 Gdansk (Poland)

2010-06-15T23:59:59.000Z

432

Statistical recoupling: A new way to break the link between electric-utility sales and revenues  

SciTech Connect

In 1991, US electric utilities spent almost $1.8 billion on demand-side management (DSM) programs. These programs cut peak demands 5% and reduced electricity sales 1% that year. Utility projections suggest that these reductions will increase to 9% and 3%, respectively, by the year 2001. However, utility DSM efforts vary enormously across the country, concentrated in a few states along the east and west coasts and the upper midwest. To some extent, this concentration is a function of regulatory reforms that remove disincentives to utility shareholders for investments in DSM programs. A key component of these reforms is recovery of the net lost revenues caused by utility DSM programs. These lost revenues occur between rate cases when a utility encourages its customers to improve energy efficiency and cut demand. The reduction in sales means that the utility has less revenue to cover its fixed costs. This report describes a new method, statistical recoupling (SR), that addresses this net-lost-revenue problem. Like other decoupling approaches, SR breaks the link between electric-utility revenues and sales. Unlike other approaches, SR minimizes changes from traditional regulation. In particular, the risks of revenue swings associated with year-to-year changes in weather and the economy remain with the utility under SR. Statistical recoupling uses statistical models, based on historical data, that explain retail electricity sales as functions of the number of utility customers, winter and summer weather, the condition of the local economy, electricity price, and perhaps a few other key variables. These models, along with the actual values of the explanatory variables, are then used to estimate ``allowed`` electricity sales and revenues in future years.

Hirst, E.

1993-09-01T23:59:59.000Z

433

Sensitivity Studies for Main Steam Line Break Exercises 2 and 3 with RELAP5/PANBOX  

SciTech Connect

This paper presents and discusses results obtained with the nuclear plant safety analysis code system RELAP5/PANBOX (R/P/C) for the return-to-power scenario of exercises 2 and 3 of the Organization for Economic Cooperation and Development/Nuclear Energy Agency Main Steam Line Break (MSLB) Benchmark. Both the external and internal coupling options of R/P/C have been considered for exercise 3; i.e., the COBRA module of PANBOX was used to calculate the core thermal hydraulics in the external coupling option, whereas the core thermal hydraulics of RELAP5 was used in the internal coupling option. For the representation of thermal-hydraulic channels, a fine channel geometry based on the 177 fuel assemblies was selected for the external coupling option, and a coarse channel geometry based on 19 coarse channels has been investigated for the internal coupling option. The comparison of the results shows very good agreement of important core parameters between the considered coupling variants. Both exercises 2 and 3 have been investigated with respect to local safety parameters like fuel centerline temperatures and minimum departure from nucleate boiling ratios using the on-line hot subchannel analysis capability of R/P/C in the external coupling option. The results show that both quantities are far from the safety-related limits.The benchmark demonstrates, that R/P/C - as part of the integrated CASCADE-3D core analysis system of Framatome ANP GmbH - has proven to be a powerful tool for detailed analyses of an MSLB accident.

Boeer, Rainer; Knoll, Alfred [Framatome ANP GmbH (France)

2003-05-15T23:59:59.000Z

434

Charge-symmetry breaking forces and isospin mixing in 8Be  

E-Print Network (OSTI)

We report Green's function Monte Carlo calculations of isospin-mixing (IM) matrix elements for the 2+, 1+, and 3+ T=0,1 pairs of states at 16--19 MeV excitation in 8Be. The realistic Argonne v18 (AV18) two-nucleon and Illinois-7 three-nucleon potentials are used to generate the nuclear wave functions. Contributions from the full electromagnetic interaction and strong class III charge-symmetry-breaking (CSB) components of the AV18 potential are evaluated. We also examine two theoretically more complete CSB potentials based on rho-omega mixing, tuned to give the same neutron-neutron scattering length as AV18. The contribution of these different CSB potentials to the 3H-3He, 7Li-7Be, and 8Li-8B isovector energy differences is evaluated and reasonable agreement with experiment is obtained. Finally, for the 8Be IM calculation we add the small class IV CSB terms coming from one-photon, one-pion, and one-rho exchange, as well as rho-omega mixing. The expectation values of the three CSB models vary by up to 20% in the isovector energy differences, but only by 10% or less in the IM matrix element. The total matrix element gives 85--90% of the experimental IM value of -145 keV for the 2+ doublet, with about two thirds coming from the Coulomb interaction. We also report the IM matrix element to the first 2+ state at 3 MeV excitation, which is the final state for various tests of the Standard Model for beta-decay.

R. B. Wiringa; S. Pastore; Steven C. Pieper; Gerald A. Miller

2013-08-26T23:59:59.000Z

435

Correlations of whitecap coverage and gas transfer velocity with microwave brightness temperature for plunging and spilling breaking waves  

DOE Green Energy (OSTI)

Bubbles and bubble plumes generated by wind-induced breaking waves significantly enhance the gas exchange across the interface between the ocean and atmosphere under high-wind conditions. Whitcaps, or active spilling wave crests, are the sea-surface manifestation of the bubbles and bubble plumes in the subsurface mixed layer, and the fractional area of the sea surface covered by which has been proposed to correlate linearly with the air-sea gas transfer velocity. The presence of whitecaps substantially increases the microwave brightness temperature of the sea surface. It could be possible to estimate the whitecap coverage from the sea-surface microwave brightness temperature would also be very helpful in developing a remote-sensing model for predicting air-sea gas transfer velocities from microwave brightness temperatures. As a part of an air-water gas exchange experiment conducted in an outdoor surf pool, measurements were made that were designed to investigate the correlation between whitecap coverage and microwave brightness temperature. A mechanical wave maker was located at the deep end of the pool and the generated waves propagate and break towards the shallow end of the pool. Two wave patterns characteristic of plunging and spilling breaking waves at four wave heights from 0.3 m to 1.2 m were produced.

Wang, Qin; Monahan, E.C. [Connecticut Univ., Groton, CT (United States). Marine Sciences Inst.; Asher, W.E. [Battelle/Marine Sciences Lab., Sequim, WA (United States); Smith, P.M. [Naval Research Lab. Detachment, Stennis Space Center, MS (United States)

1995-07-01T23:59:59.000Z

436

Analysis of Kuosheng Large-Break Loss-of-Coolant Accident with MELCOR 1.8.4  

SciTech Connect

The MELCOR code, developed by Sandia National Laboratories, is capable of simulating the severe accident phenomena of light water reactor nuclear power plants (NPPs). A specific large-break loss-of-coolant accident (LOCA) for Kuosheng NPP is simulated with the use of the MELCOR 1.8.4 code. This accident is induced by a double-ended guillotine break of one of the recirculation pipes concurrent with complete failure of the emergency core cooling system. The MELCOR input deck for the Kuosheng NPP is established based on the design data of the Kuosheng NPP and the MELCOR users' guides. The initial steady-state conditions are generated with a developed self-initialization algorithm. The effect of the MELCOR 1.8.4-provided initialization process is demonstrated. The main severe accident phenomena and the corresponding fission product released fractions associated with the large-break LOCA sequences are simulated. The MELCOR 1.8.4 predicts a longer time interval between the core collapse and vessel failure and a higher source term. This MELCOR 1.8.4 input deck will be applied to the probabilistic risk assessment, the severe accident analysis, and the severe accident management study of the Kuosheng NPP in the near future.

Wang, T.-C.; Wang, S.-J.; Chien, C.-S

2000-09-15T23:59:59.000Z

437

RELAP5YA simulation of LOFT small-break experiments L3-6 and L5-1  

Science Conference Proceedings (OSTI)

The loss-of-fluid test (LOFT) small-break tests were simulated using the RELAP5YA computer code at Yankee Atomic Electric Company (YAEC) as part of the integral code assessment program. RELAP5YA was developed at YAEC from RELAP5/MOD1 to provide a method for licensing analysis for small-break loss-of-coolant accidents (SBLOCAs) in pressurized water reactors (PWRs). The LOFT facility is a 50-MW(thermal) volumetrically scaled PWR that has been designed to simulate the significant thermal-hydraulic events expected in a commercial PWR during postulated LOCAs. The tests selected for this assessment were LOFT tests L3-6/L8-1 and L5-1. The present RELAP5YA model of the LOFT facility consists of 99 volumes, 105 junctions, and 59 heat slabs and includes all the necessary components (e.g., pumps and valves) and control systems (e.g., trip logic and pressure regulating valves) to provide an accurate simulation of the test sequence. These comparisons of the calculated and measured data for the LOFT small-break tests indicate that RELAP5YA generally matched important safety-related phenomena, such as system depressurization, primary coolant mass inventory, and core heatup and quench. The benchmarking results are currently being employed at YAEC to direct RELAP5YA modeling improvements for PWR SBLOCA applications.

Schor, L.; Harvey, R.C.

1987-01-01T23:59:59.000Z

438

Method for in vitro recombination  

DOE Patents (OSTI)

The present invention relates to an in vitro method, using isolated protein reagents, for joining two double-stranded (ds) DNA molecules of interest, wherein the distal region of the first DNA molecule and the proximal region of the second DNA molecule share a region of sequence identity. The method allows the joining of a number of DNA fragments, in a predetermined order and orientation, without the use of restriction enzymes. It can be used, e.g., to join synthetically produced sub-fragments of a gene or genome of interest.

Gibson, Daniel Glenn; Smith, Hamilton O

2013-05-07T23:59:59.000Z

439

Property:NEPA DNA Worksheet | Open Energy Information  

Open Energy Info (EERE)

DNA Worksheet DNA Worksheet Jump to: navigation, search Property Name NEPA DNA Worksheet Property Type Page Description DNA Worksheet files for NEPA Docs. This is a property of type Page. It links to pages that use the form NEPA_Doc. Pages using the property "NEPA DNA Worksheet" Showing 19 pages using this property. D DOI-BLM-NV-C010-2011-0517-DNA + DOI-BLM-NV-C010-2011-0517-DNA.pdf + DOI-BLM-NV-C010-2012--044-DNA + DOI-BLM-NV-C010-2012-0044-DNA.pdf + DOI-BLM-NV-C010-2012-0005-DNA + DOI-BLM-NV-C010-2012-0005-DNA.pdf + DOI-BLM-NV-C010-2012-0016-DNA + DOI-BLM-NV-C010-2012-0016-DNA.pdf + DOI-BLM-NV-C010-2012-0019-DNA + DOI-BLM-NV-C010-2012-0019-DNA.pdf + DOI-BLM-NV-C010-2012-0020-DNA + DOI-BLM-NV-C010-2012-0020-DNA.pdf + DOI-BLM-NV-C010-2012-0028-DNA + DOI-BLM-NV-C010-2012-0028-DNA.pdf +

440

Recombinant DNA encoding a desulfurization biocatalyst  

DOE Patents (OSTI)

This invention relates to a recombinant DNA molecule containing a gene or genes which encode a biocatalyst capable of desulfurizing a fossil fuel which contains organic sulfur molecules. For example, the present invention encompasses a recombinant DNA molecule containing a gene or genes of a strain of Rhodococcus rhodochrous.

Rambosek, John (Seattle, WA); Piddington, Chris S. (Seattle, WA); Kovacevich, Brian R. (Seattle, WA); Young, Kevin D. (Grand Forks, ND); Denome, Sylvia A. (Thompson, ND)

1994-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Recombinant DNA encoding a desulfurization biocatalyst  

DOE Patents (OSTI)

This invention relates to a recombinant DNA molecule containing a gene or genes which encode a biocatalyst capable of desulfurizing a fossil fuel which contains organic sulfur molecules. For example, the present invention encompasses a recombinant DNA molecule containing a gene or genes of a strain of Rhodococcus rhodochrous. 13 figs.

Rambosek, J.; Piddington, C.S.; Kovacevich, B.R.; Young, K.D.; Denome, S.A.

1994-10-18T23:59:59.000Z

442

The Initiation of Bacterial DNA Replication  

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

The Initiation of Bacterial DNA The Initiation of Bacterial DNA Replication The Initiation of Bacterial DNA Replication Print Wednesday, 31 January 2007 00:00 For the first time, scientists have determined the structure of the initiator of bacterial DNA replication. It is already known that such replication is controlled by a protein known as DnaA, a member of the AAA+ superfamily of ATPases. What has now been discovered is that the core of the initiator is not the closed-ring structure expected for this system. Instead, DnaA forms an open right-handed helix. In addition, the architecture indicates that this AAA+ superhelix will wrap coils of the DNA around its exterior, causing the DNA double helix to deform as a first step in the separation and unwinding of its strands. Eukaryotic and archaeal initiators also have the structural elements that promote open-helix formation, indicating that a spiral, open-ring AAA+ assembly is a conserved element from a common evolutionary ancestor of Archaea, Bacteria, and Eukarya.

443

Crystal structure of the N-terminal region of human Ash2L shows a winged-helix motif involved in DNA binding  

Science Conference Proceedings (OSTI)

Ash2L is a core component of the MLL family histone methyltransferases and has an important role in regulating the methylation of histone H3 on lysine 4. Here, we report the crystal structure of the N-terminal domain of Ash2L and reveal a new function of Ash2L. The structure shows that Ash2L contains an atypical PHD finger that does not have histone tail-binding activity. Unexpectedly, the structure shows a previously unrecognized winged-helix motif that directly binds to DNA. The DNA-binding-deficient mutants of Ash2L reduced Ash2L localization to the HOX locus. Strikingly, a single mutation in Ash2L{sub WH} (K131A) breaks the chromatin domain boundary, suggesting that Ash2L also has a role in chromosome demarcation.

Chen, Yong; Wan, Bingbing; Wang, Kevin C.; Cao, Fang; Yang, Yuting; Protacio, Angeline; Dou, Yali; Chang, Howard Y.; Lei, Ming (Michigan-Med); (HHMI)

2011-09-06T23:59:59.000Z

444

Commercial Aircraft Corporation of China (Comac) attempts to break the Airbus-Boeing duopoly, will it succeed? : an industry analysis framework applied  

E-Print Network (OSTI)

Using an industry analysis framework, this thesis analyzes whether the recently established Commercial Aircraft Corporation of China (Comac) is likely to break the Boeing-Airbus duopoly in the industry of large commercial ...

Fuentes, Jose L., S.M. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

445

Breaking symmetries in ordered materials : spin polarized light transport in magnetized noncentrosymmetric 1D photonic crystals, and photonic gaps and fabrication of quasiperiodic structured materials from interference lithography  

E-Print Network (OSTI)

Effects of breaking various symmetries on optical properties in ordered materials have been studied. Photonic crystals lacking space-inversion and time-reversal symmetries were shown to display nonreciprocal dispersion ...

Bita, Ion

2006-01-01T23:59:59.000Z

446

Links between Rossby Wave Breaking and the North Atlantic Oscillation–Arctic Oscillation in Present-Day and Last Glacial Maximum Climate Simulations  

Science Conference Proceedings (OSTI)

Upper-tropospheric Rossby wave–breaking processes are examined in coupled ocean–atmosphere simulations of the Last Glacial Maximum (LGM) and of the modern era. LGM statistics of the Northern Hemisphere in winter, computed from the Paleoclimate ...

Gwendal Rivière; Alexandre Laîné; Guillaume Lapeyre; David Salas-Mélia; Masa Kageyama

2010-06-01T23:59:59.000Z

447

NGFAST: a simulation model for rapid assessment of impacts of natural gas pipeline breaks and flow reductions at U.S. state borders and import points  

Science Conference Proceedings (OSTI)

This paper describes NGfast, the new simulation and impact-analysis tool developed by Argonne National Laboratory for rapid, first-stage assessments of impacts of major pipeline breaks. The methodology, calculation logic, and main assumptions are discussed. ...

Edgar C. Portante; Brian A. Craig; Stephen M. Folga

2007-12-01T23:59:59.000Z

448

When DNA Needs to Stand Up and Be Counted  

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

When DNA Needs to Stand Up and Be Counted When DNA Needs to Stand Up and Be Counted Print Wednesday, 31 May 2006 00:00 DNA microarrays are small metal, glass, or silicon chips...

449

Allosteric Modulation of DNA by Small Molecules  

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

Allosteric Modulation of DNA by Small Allosteric Modulation of DNA by Small Molecules Signals originating at the cell surface are conveyed by a complex system of interconnected signaling pathways to the nucleus. They converge at transcription factors, which in turn regulate the transcription of sets of genes that result in the gene expression. Many human diseases are caused by dysregulated gene expression and the oversupply of transcription factors may be required for the growth and metastatic behavior of human cancers. Cell permeable small molecules that can be programmed to disrupt transcription factor-DNA interfaces could silence aberrant gene expression pathways. Pyrrole-imidazole polyamides are DNA minor groove binding small molecules that are programmable for a large repertoire of DNA motifs.

450

Storing data encoded DNA in living organisms  

DOE Patents (OSTI)

Current technologies allow the generation of artificial DNA molecules and/or the ability to alter the DNA sequences of existing DNA molecules. With a careful coding scheme and arrangement, it is possible to encode important information as an artificial DNA strand and store it in a living host safely and permanently. This inventive technology can be used to identify origins and protect R&D investments. It can also be used in environmental research to track generations of organisms and observe the ecological impact of pollutants. Today, there are microorganisms that can survive under extreme conditions. As well, it is advantageous to consider multicellular organisms as hosts for stored information. These living organisms can provide as memory housing and protection for stored data or information. The present invention provides well for data storage in a living organism wherein at least one DNA sequence is encoded to represent data and incorporated into a living organism.

Wong; Pak C. (Richland, WA), Wong; Kwong K. (Sugar Land, TX), Foote; Harlan P. (Richland, WA)

2006-06-06T23:59:59.000Z

451

Method for sequencing DNA base pairs  

DOE Patents (OSTI)

The base pairs of a DNA structure are sequenced with the use of a scanning tunneling microscope (STM). The DNA structure is scanned by the STM probe tip, and, as it is being scanned, the DNA structure is separately subjected to a sequence of infrared radiation from four different sources, each source being selected to preferentially excite one of the four different bases in the DNA structure. Each particular base being scanned is subjected to such sequence of infrared radiation from the four different sources as that particular base is being scanned. The DNA structure as a whole is separately imaged for each subjection thereof to radiation from one only of each source. 6 figures.

Sessler, A.M.; Dawson, J.

1993-12-14T23:59:59.000Z

452

Improved method for sequencing DNA base pairs  

DOE Patents (OSTI)

The base pairs of a DNA structure are sequenced with the use of a scanning tunneling microscope (STM). The DNA structure is scanned by the STM probe tip, and, as it is being scanned, the DNA structure is separately subjected to a sequence of infrared radiation from four different sources, each source being selected to preferentially excite one of the four different bases in the DNA structure. Each particular base being scanned is subjected to such sequence of infrared radiation from the four different sources as that particular base is being scanned. The DNA structure as a whole is separately imaged for each subjection thereof to radiation from one only of each source. 1 ref.

Sessler, A.M.; Dawson, J.

1990-12-31T23:59:59.000Z

453

Improved method for sequencing DNA base pairs  

DOE Patents (OSTI)

The base pairs of a DNA structure are sequenced with the use of a scanning tunneling microscope (STM). The DNA structure is scanned by the STM probe tip, and, as it is being scanned, the DNA structure is separately subjected to a sequence of infrared radiation from four different sources, each source being selected to preferentially excite one of the four different bases in the DNA structure. Each particular base being scanned is subjected to such sequence of infrared radiation from the four different sources as that particular base is being scanned. The DNA structure as a whole is separately imaged for each subjection thereof to radiation from one only of each source. 1 ref.

Sessler, A.M.; Dawson, J.

1990-01-01T23:59:59.000Z

454

Flow cytometric detection method for DNA samples  

Science Conference Proceedings (OSTI)

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM.TM. on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA.TM., on the 5' end.

Nasarabadi,Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Round Rock, TX)

2011-07-05T23:59:59.000Z

455

Flow cytometric detection method for DNA samples  

DOE Patents (OSTI)

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM, on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA, on the 5' end.

Nasarabadi, Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Livermore, CA)

2006-08-01T23:59:59.000Z

456

Flow cytometric detection method for DNA samples  

DOE Patents (OSTI)

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM.TM. on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA.TM., on the 5' end.

Nasarabadi,Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Round Rock, TX)

2011-07-05T23:59:59.000Z

457

Crystal Structure of the Chromodomain Helicase DNA-binding Protein 1 (Chd1) DNA-binding Domain in Complex with DNA  

Science Conference Proceedings (OSTI)

Chromatin remodelers are ATP-dependent machines that dynamically alter the chromatin packaging of eukaryotic genomes by assembling, sliding, and displacing nucleosomes. The Chd1 chromatin remodeler possesses a C-terminal DNA-binding domain that is required for efficient nucleosome sliding and believed to be essential for sensing the length of DNA flanking the nucleosome core. The structure of the Chd1 DNA-binding domain was recently shown to consist of a SANT and SLIDE domain, analogous to the DNA-binding domain of the ISWI family, yet the details of how Chd1 recognized DNA were not known. Here we present the crystal structure of the Saccharomyces cerevisiae Chd1 DNA-binding domain in complex with a DNA duplex. The bound DNA duplex is straight, consistent with the preference exhibited by the Chd1 DNA-binding domain for extranucleosomal DNA. Comparison of this structure with the recently solved ISW1a DNA-binding domain bound to DNA reveals that DNA lays across each protein at a distinct angle, yet contacts similar surfaces on the SANT and SLIDE domains. In contrast to the minor groove binding seen for Isw1 and predicted for Chd1, the SLIDE domain of the Chd1 DNA-binding domain contacts the DNA major groove. The majority of direct contacts with the phosphate backbone occur only on one DNA strand, suggesting that Chd1 may not strongly discriminate between major and minor grooves.

Sharma A.; Heroux A.; Jenkins K. R.; Bowman G. D.

2011-12-09T23:59:59.000Z

458

Electronic transport and localization in short and long DNA  

E-Print Network (OSTI)

The question of whether DNA conducts electric charges is intriguing to physicists and biologists alike. The suggestion that electron transfer/transport in DNA might be biologically important has triggered a series of experimental and theoretical investigations. Here, we review recent theoretical progress by concentrating on quantum-chemical, molecular dynamics-based approaches to short DNA strands and physics-motivated tight-binding transport studies of long or even complete DNA sequences. In both cases, we observe small, but significant differences between specific DNA sequences such as periodic repetitions and aperiodic sequences of AT bases, lambda-DNA, centromeric DNA, promoter sequences as well as random-ATGC DNA.

H. Wang; R. Marsh; J. P. Lewis; R. A. Roemer

2005-11-04T23:59:59.000Z

459

NREL: Fleet Test and Evaluation - Fleet DNA: Vehicle Drive Cycle...  

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

Fleet DNA Project graphic depicting a trail of data emerging from trucks. Fleet DNA helps vehicle manufacturers and fleet managers understand the broad operational range for many...

460

Low-cost, Rapid DNA Sequencing Technique - Energy Innovation Portal  

Description Sequencing DNA is crucial for future breakthroughs in biological and biomedical research. ... DNA sequencing for medical applications has been restricted ...

Note: This page contains sample records for the topic "dna double-strand breaks" 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

Computational Challenges in Simulating Large DNA over Long Times  

Science Conference Proceedings (OSTI)

Simulating DNA’s dynamics requires a sophisticated array of algorithms appropriate for DNA’s impressive spectrum of spatial and temporal levels. The authors describe computational challenges

Tamar Schlick; Daniel A. Beard; Jing Huang; Daniel A. Strahs; Xiaoliang Qian

2000-01-01T23:59:59.000Z

462

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

463

AZD5438, an Inhibitor of Cdk1, 2, and 9, Enhances the Radiosensitivity of Non-Small Cell Lung Carcinoma Cells  

SciTech Connect

Purpose: Radiation therapy (RT) is one of the primary modalities for treatment of non-small cell lung cancer (NSCLC). However, due to the intrinsic radiation resistance of these tumors, many patients experience RT failure, which leads to considerable tumor progression including regional lymph node and distant metastasis. This preclinical study evaluated the efficacy of a new-generation cyclin-dependent kinase (Cdk) inhibitor, AZD5438, as a radiosensitizer in several NSCLC models that are specifically resistant to conventional fractionated RT. Methods and Materials: The combined effect of ionizing radiation and AZD5438, a highly specific inhibitor of Cdk1, 2, and 9, was determined in vitro by surviving fraction, cell cycle distribution, apoptosis, DNA double-strand break (DSB) repair, and homologous recombination (HR) assays in 3 NSCLC cell lines (A549, H1299, and H460). For in vivo studies, human xenograft animal models in athymic nude mice were used. Results: Treatment of NSCLC cells with AZD5438 significantly augmented cellular radiosensitivity (dose enhancement ratio rangeing from 1.4 to 1.75). The degree of radiosensitization by AZD5438 was greater in radioresistant cell lines (A549 and H1299). Radiosensitivity was enhanced specifically through inhibition of Cdk1, prolonged G{sub 2}-M arrest, inhibition of HR, delayed DNA DSB repair, and increased apoptosis. Combined treatment with AZD5438 and irradiation also enhanced tumor growth delay, with an enhancement factor ranging from 1.2-1.7. Conclusions: This study supports the evaluation of newer generation Cdk inhibitors, such as AZD5438, as potent radiosensitizers in NSCLC models, especially in tumors that demonstrate variable intrinsic radiation responses.

Raghavan, Pavithra; Tumati, Vasu; Yu Lan [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)] [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Chan, Norman [Departments of Medical Biophysics and Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Ontario (Canada)] [Departments of Medical Biophysics and Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Ontario (Canada); Tomimatsu, Nozomi [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States)] [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Burma, Sandeep [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States) [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Simmons Comprehensive Cancer Center, Dallas, Texas (United States); Bristow, Robert G. [Departments of Medical Biophysics and Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Ontario (Canada)] [Departments of Medical Biophysics and Radiation Oncology, Princess Margaret Hospital, University Health Network, University of Toronto, Ontario (Canada); Saha, Debabrata, E-mail: debabrata.saha@utsouthwestern.edu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States) [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas (United States); Simmons Comprehensive Cancer Center, Dallas, Texas (United States)

2012-11-15T23:59:59.000Z

464

The Initiation of Bacterial DNA Replication  

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

The Initiation of Bacterial DNA Replication Print The Initiation of Bacterial DNA Replication Print For the first time, scientists have determined the structure of the initiator of bacterial DNA replication. It is already known that such replication is controlled by a protein known as DnaA, a member of the AAA+ superfamily of ATPases. What has now been discovered is that the core of the initiator is not the closed-ring structure expected for this system. Instead, DnaA forms an open right-handed helix. In addition, the architecture indicates that this AAA+ superhelix will wrap coils of the DNA around its exterior, causing the DNA double helix to deform as a first step in the separation and unwinding of its strands. Eukaryotic and archaeal initiators also have the structural elements that promote open-helix formation, indicating that a spiral, open-ring AAA+ assembly is a conserved element from a common evolutionary ancestor of Archaea, Bacteria, and Eukarya.

465

The Initiation of Bacterial DNA Replication  

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

The Initiation of Bacterial DNA Replication Print The Initiation of Bacterial DNA Replication Print For the first time, scientists have determined the structure of the initiator of bacterial DNA replication. It is already known that such replication is controlled by a protein known as DnaA, a member of the AAA+ superfamily of ATPases. What has now been discovered is that the core of the initiator is not the closed-ring structure expected for this system. Instead, DnaA forms an open right-handed helix. In addition, the architecture indicates that this AAA+ superhelix will wrap coils of the DNA around its exterior, causing the DNA double helix to deform as a first step in the separation and unwinding of its strands. Eukaryotic and archaeal initiators also have the structural elements that promote open-helix formation, indicating that a spiral, open-ring AAA+ assembly is a conserved element from a common evolutionary ancestor of Archaea, Bacteria, and Eukarya.