National Library of Energy BETA

Sample records for double-strand break repair

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

    SciTech Connect (OSTI)

    Zafar, Faria; Seidler, Sara B.; Kronenberg, Amy; Schild, David; Wiese, Claudia

    2010-06-29

    To test the contribution of homologous recombinational repair (HRR) in repairing DNA damaged sites induced by high-energy iron ions, we used: (1) HRR-deficient rodent cells carrying a deletion in the RAD51D gene and (2) syngeneic human cells impaired for HRR by RAD51D or RAD51 knockdown using RNA interference. We show that in response to iron ions, HRR contributes to cell survival in rodent cells, and that HRR-deficiency abrogates RAD51 foci formation. Complementation of the HRR defect by human RAD51D rescues both enhanced cytotoxicity and RAD51 foci formation. For human cells irradiated with iron ions, cell survival is decreased, and, in p53 mutant cells, the levels of mutagenesis are increased when HRR is impaired. Human cells synchronized in S phase exhibit more pronounced resistance to iron ions as compared with cells in G1 phase, and this increase in radioresistance is diminished by RAD51 knockdown. These results implicate a role for RAD51-mediated DNA repair (i.e. HRR) in removing a fraction of clustered lesions induced by charged particle irradiation. Our results are the first to directly show the requirement for an intact HRR pathway in human cells in ensuring DNA repair and cell survival in response to high-energy high LET radiation.

  2. Zinc chromate induces chromosome instability and DNA double strand breaks in human lung cells

    SciTech Connect (OSTI)

    Xie Hong; Holmes, Amie L.; Young, Jamie L.; Qin Qin; Joyce, Kellie; Pelsue, Stephen C.; Peng Cheng; Wise, Sandra S.; Jeevarajan, Antony S.; Wallace, William T.; Hammond, Dianne; Wise, John Pierce E-mail: John.Wise@usm.maine.edu

    2009-02-01

    Hexavalent chromium Cr(VI) is a respiratory toxicant and carcinogen, with solubility playing an important role in its carcinogenic potential. Zinc chromate, a water insoluble or 'particulate' Cr(VI) compound, has been shown to be carcinogenic in epidemiology studies and to induce tumors in experimental animals, but its genotoxicity is poorly understood. Our study shows that zinc chromate induced concentration-dependent increases in cytotoxicity, chromosome damage and DNA double strand breaks in human lung cells. In response to zinc chromate-induced breaks, MRE11 expression was increased and ATM and ATR were phosphorylated, indicating that the DNA double strand break repair system was initiated in the cells. In addition, our data show that zinc chromate-induced double strand breaks were only observed in the G2/M phase population, with no significant amount of double strand breaks observed in G1 and S phase cells. These data will aid in understanding the mechanisms of zinc chromate toxicity and carcinogenesis.

  3. Defects in the kinetics of the repair of DNA double-strand breaks and inhibition of DNA synthesis in the ataxia telangiectasia AT5Bl-VA cell line: Comparison to a corrected hybrid, atxbc

    SciTech Connect (OSTI)

    Kysela, B.P.; Lohrer, H.; Arrand, J.E.

    1995-12-01

    The nature of the primary biochemical defect in the human radiosensitive and cancer-prone syndrome, ataxia telangiectasia (AT), has remained obscure despite many efforts to elucidate it. In this study, AT complementation group D cells and a nearly isogenic corrected AT-hamster hybrid derivative have been analyzed for induction and repair of initial double-strand breaks (DSBs) after exposure to ionizing radiation, using a sensitive field-inversion electrophoresis technique. Results suggesting that initial levels of damage are the same in these two cell types, but indicating differences in the fast component of DNA repair, have been compared and correlated with those resulting from a study of the radioresistant DNA synthesis defect and its correction in the same cell lines. These measurements show that the radioresistant phenotype of the substantially corrected AT-hamster hybrid correlates with its higher level of fast-component DSB repair and higher level of inhibition of DNA synthesis, but that the initial damage induction does not contribute to the phenotype. We propose that the AT gene product(s) is likely to act early in a signaling pathway which controls both DNA repair and progression of cells through the phases of the cell cycle in response to ionizing radiation. 36 refs., 3 figs., 2 tabs.

  4. Probability of double-strand breaks in genome-sized DNA by {gamma}-ray decreases markedly as the DNA concentration increases

    SciTech Connect (OSTI)

    Shimobayashi, Shunsuke F.; Iwaki, Takafumi; Mori, Toshiaki; Yoshikawa, Kenichi

    2013-05-07

    By use of the single-molecule observation, we count the number of DNA double-strand breaks caused by {gamma}-ray irradiation with genome-sized DNA molecules (166 kbp). We find that P{sub 1}, the number of double-strand breaks (DSBs) per base pair per unit Gy, is nearly inversely proportional to the DNA concentration above a certain threshold DNA concentration. The inverse relationship implies that the total number of DSBs remains essentially constant. We give a theoretical interpretation of our experimental results in terms of attack of reactive species upon DNA molecules, indicating the significance of the characteristics of genome-sized giant DNA as semiflexible polymers for the efficiency of DSBs.

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

    SciTech Connect (OSTI)

    Ibanez, Irene L.; Bracalente, Candelaria; Molinari, Beatriz L.; Palmieri, Monica A.; Policastro, Lucia; Kreiner, Andres J.; Burlon, Alejandro A.; Valda, Alejandro; Navalesi, Daniela; Davidson, Jorge; Davidson, Miguel; Vazquez, Monica; Ozafran, Mabel; Duran, Hebe

    2009-07-15

    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.

  6. Double stranded nucleic acid biochips

    DOE Patents [OSTI]

    Chernov, Boris; Golova, Julia

    2006-05-23

    This invention describes a new method of constructing double-stranded DNA (dsDNA) microarrays based on the use of pre-synthesized or natural DNA duplexes without a stem-loop structure. The complementary oligonucleotide chains are bonded together by a novel connector that includes a linker for immobilization on a matrix. A non-enzymatic method for synthesizing double-stranded nucleic acids with this novel connector enables the construction of inexpensive and robust dsDNA/dsRNA microarrays. DNA-DNA and DNA-protein interactions are investigated using the microarrays.

  7. Solid phase sequencing of double-stranded nucleic acids

    DOE Patents [OSTI]

    Fu, Dong-Jing; Cantor, Charles R.; Koster, Hubert; Smith, Cassandra L.

    2002-01-01

    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.

  8. Radiation-Induced Upregulation of Gene Expression From Adenoviral Vectors Mediated by DNA Damage Repair and Regulation

    SciTech Connect (OSTI)

    Nokisalmi, Petri; Rajecki, Maria; Pesonen, Sari; Escutenaire, Sophie; Soliymani, Rabah; Tenhunen, Mikko; Ahtiainen, Laura; Hemminki, Akseli

    2012-05-01

    Purpose: In the present study, we evaluated the combination of replication-deficient adenoviruses and radiotherapy in vitro. The purpose of the present study was to analyze the mechanism of radiation-mediated upregulation of adenoviral transgene expression. Methods and Materials: Adenoviral transgene expression (luciferase or green fluorescent protein) was studied with and without radiation in three cell lines: breast cancer M4A4-LM3, prostate cancer PC-3MM2, and lung cancer LNM35/enhanced green fluorescent protein. The effect of the radiation dose, modification of the viral capsid, and five different transgene promoters were studied. The cellular responses were studied using mass spectrometry and immunofluorescence analysis. Double strand break repair was modulated by inhibitors of heat shock protein 90, topoisomerase-I, and DNA protein kinase, and transgene expression was measured. Results: We found that a wide range of radiation doses increased adenoviral transgene expression regardless of the cell line, transgene, promoter, or viral capsid modification. Treatment with adenovirus, radiation, and double strand break repair inhibitors resulted in persistence of double strand breaks and subsequent increases in adenovirus transgene expression. Conclusions: Radiation-induced enhancement of adenoviral transgene expression is linked to DNA damage recognition and repair. Radiation induces a global cellular response that results in increased production of RNA and proteins, including adenoviral transgene products. This study provides a mechanistic rationale for combining radiation with adenoviral gene delivery.

  9. Binding of undamaged double stranded DNA to vaccinia virus uracil-DNA glycosylase

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

    Schormann, Norbert; Banerjee, Surajit; Ricciardi, Robert; Chattopadhyay, Debasish

    2015-06-02

    Background: Uracil-DNA glycosylases are evolutionarily conserved DNA repair enzymes. However, vaccinia virus uracil-DNA glycosylase (known as D4), also serves as an intrinsic and essential component of the processive DNA polymerase complex during DNA replication. In this complex D4 binds to a unique poxvirus specific protein A20 which tethers it to the DNA polymerase. At the replication fork the DNA scanning and repair function of D4 is coupled with DNA replication. So far, DNA-binding to D4 has not been structurally characterized. Results: This manuscript describes the first structure of a DNA-complex of a uracil-DNA glycosylase from the poxvirus family. This alsomore » represents the first structure of a uracil DNA glycosylase in complex with an undamaged DNA. In the asymmetric unit two D4 subunits bind simultaneously to complementary strands of the DNA double helix. Each D4 subunit interacts mainly with the central region of one strand. DNA binds to the opposite side of the A20-binding surface on D4. In comparison of the present structure with the structure of uracil-containing DNA-bound human uracil-DNA glycosylase suggests that for DNA binding and uracil removal D4 employs a unique set of residues and motifs that are highly conserved within the poxvirus family but different in other organisms. Conclusion: The first structure of D4 bound to a truly non-specific undamaged double-stranded DNA suggests that initial binding of DNA may involve multiple non-specific interactions between the protein and the phosphate backbone.« less

  10. Binding of undamaged double stranded DNA to vaccinia virus uracil-DNA glycosylase

    SciTech Connect (OSTI)

    Schormann, Norbert; Banerjee, Surajit; Ricciardi, Robert; Chattopadhyay, Debasish

    2015-06-02

    Background: Uracil-DNA glycosylases are evolutionarily conserved DNA repair enzymes. However, vaccinia virus uracil-DNA glycosylase (known as D4), also serves as an intrinsic and essential component of the processive DNA polymerase complex during DNA replication. In this complex D4 binds to a unique poxvirus specific protein A20 which tethers it to the DNA polymerase. At the replication fork the DNA scanning and repair function of D4 is coupled with DNA replication. So far, DNA-binding to D4 has not been structurally characterized. Results: This manuscript describes the first structure of a DNA-complex of a uracil-DNA glycosylase from the poxvirus family. This also represents the first structure of a uracil DNA glycosylase in complex with an undamaged DNA. In the asymmetric unit two D4 subunits bind simultaneously to complementary strands of the DNA double helix. Each D4 subunit interacts mainly with the central region of one strand. DNA binds to the opposite side of the A20-binding surface on D4. In comparison of the present structure with the structure of uracil-containing DNA-bound human uracil-DNA glycosylase suggests that for DNA binding and uracil removal D4 employs a unique set of residues and motifs that are highly conserved within the poxvirus family but different in other organisms. Conclusion: The first structure of D4 bound to a truly non-specific undamaged double-stranded DNA suggests that initial binding of DNA may involve multiple non-specific interactions between the protein and the phosphate backbone.

  11. Spin transport and spin polarization properties in double-stranded DNA

    SciTech Connect (OSTI)

    Simchi, Hamidreza; Esmaeilzadeh, Mahdi Mazidabadi, Hossein

    2013-11-21

    We study the spin-dependent electron transport through a double-stranded DNA (dsDNA) using the Bogoliubov-de Gennes equations and non-equilibrium Green's function method. We calculate the spin-dependent electron conductance and spin-polarization for different lengths, helix angles, twist angles of dsDNA, the environment-induced dephasing factors, and hopping integral. It is shown that the conductance decreases by increasing the length and dephasing factor. Also, we show that the spin-polarization depends on the helical symmetry and the length of DNA. It is shown that the double-stranded DNA can act as a perfect spin filter. Finally, we show that the sign of spin polarization can be inverted from +1 (−1) to −1 (+1) for some values of hopping integral.

  12. Screening Tool for Providers of Double-Stranded DNA - Energy Innovation

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

    Portal Startup America Startup America Industrial Technologies Industrial Technologies Energy Analysis Energy Analysis Biomass and Biofuels Biomass and Biofuels Find More Like This Return to Search Screening Tool for Providers of Double-Stranded DNA Oak Ridge National Laboratory Contact ORNL About This Technology Publications: PDF Document Publication 11-G00227_ID2510 (2).pdf (829 KB) Technology Marketing SummaryThe invention screens purchase orders submitted to DNA synthesis

  13. The effect of a magnetic field on the spin-selective transport in double-stranded DNA

    SciTech Connect (OSTI)

    Simchi, Hamidreza; Esmaeilzadeh, Mahdi Mazidabadi, Hossein

    2014-05-28

    Spin-polarization in double-stranded DNA is studied in the presence of a magnetic field applied along its helix axis using the non-equilibrium Green's function method. The spin-polarization could be tuned by changing the magnetic field. In some special cases, the double-stranded DNA behaved as a perfect spin-filter. Furthermore, the dependency of the spin-polarization on the spin-orbit strength and dephasing strength is studied.

  14. Proximity-induced superconductivity effect in a double-stranded DNA

    SciTech Connect (OSTI)

    Simchi, Hamidreza; Esmaeilzadeh, Mahdi Mazidabadi, Hossein

    2014-02-07

    We study the proximity-induced superconductivity effect in a double-stranded DNA by solving the Bogoliubov-de Gennes equations and taking into account the effect of thermal fluctuations of the twist angle between neighboring base pairs. We show that the electron conductance is spin-dependent and the conductance of spin up (down) increases (decreases) due to the spin-orbit coupling (SOC). It is found that, for T < 100 K, the band gap energy is temperature-independent and it decreases due to the SOC. In addition, by solving the Bogoliubov-de Gennes equations and local gap parameter equation self-consistently, we find the critical temperature at which transition to superconductivity can take place.

  15. Double-stranded DNA organization in bacteriophage heads: An alternative toroid-based model

    SciTech Connect (OSTI)

    Hud, N.V.

    1995-10-01

    Studies of the organization of double-stranded DNA within bacteriophage heads during the past four decades have produced a wealth of data. However, despite the presentation of numerous models, the true organization of DNA within phage heads remains unresolved. The observations of toroidal DNA structures in electron micrographs of phage lysates have long been cited as support for the organization of DNA in a spool-like fashion. This particular model, like all other models, has not been found to be consistent with all available data. Recently, the authors proposed that DNA within toroidal condensates produced in vitro is organized in a manner significantly different from that suggested by the spool model. This new toroid model has allowed the development of an alternative model for DNA organization within bacteriophage heads that is consistent with a wide range of biophysical data. Here the authors propose that bacteriophage DNA is packaged in a toroid that is folded into a highly compact structure.

  16. Double-stranded RNA transcribed from vector-based oligodeoxynucleotide acts as transcription factor decoy

    SciTech Connect (OSTI)

    Xiao, Xiao; Gang, Yi; Wang, Honghong; Wang, Jiayin; Zhao, Lina; Xu, Li; Liu, Zhiguo

    2015-02-06

    Highlights: • A shRNA vector based transcription factor decoy, VB-ODN, was designed. • VB-ODN for NF-κB inhibited cell viability in HEK293 cells. • VB-ODN inhibited expression of downstream genes of target transcription factors. • VB-ODN may enhance nuclear entry ratio for its feasibility of virus production. - Abstract: In this study, we designed a short hairpin RNA vector-based oligodeoxynucleotide (VB-ODN) carrying transcription factor (TF) consensus sequence which could function as a decoy to block TF activity. Specifically, VB-ODN for Nuclear factor-κB (NF-κB) could inhibit cell viability and decrease downstream gene expression in HEK293 cells without affecting expression of NF-κB itself. The specific binding between VB-ODN produced double-stranded RNA and NF-κB was evidenced by electrophoretic mobility shift assay. Moreover, similar VB-ODNs designed for three other TFs also inhibit their downstream gene expression but not that of themselves. Our study provides a new design of decoy for blocking TF activity.

  17. Activation of double-stranded RNA-dependent protein kinase inhibits proliferation of pancreatic ?-cells

    SciTech Connect (OSTI)

    Chen, Shan-Shan [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China) [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China); Jiang, Teng [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China)] [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China); Wang, Yi; Gu, Li-Ze [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China) [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China); Wu, Hui-Wen [Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing (China)] [Laboratory Center for Basic Medical Sciences, Nanjing Medical University, Nanjing (China); Tan, Lan [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China)] [Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Nanjing (China); Guo, Jun, E-mail: Guoj@njmu.edu.cn [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China) [Key Laboratory of Human Functional Genomics of Jiangsu Province, Nanjing Medical University, Nanjing (China); Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing (China)

    2014-01-17

    Highlights: PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in ?-cells. Activated PKR inhibited ?-cell proliferation by arresting cell cycle at G1 phase. Activated PKR fully abrogated the pro-proliferative effects of IGF-I on ?-cells. -- Abstract: Double-stranded RNA-dependent protein kinase (PKR) is revealed to participate in the development of insulin resistance in peripheral tissues in type 2 diabetes (T2DM). Meanwhile, PKR is also characterized as a critical regulator of cell proliferation. To date, no study has focused on the impact of PKR on the proliferation of pancreatic ?-cells. Here, we adopted insulinoma cell lines and mice islet ?-cells to investigate: (1) the effects of glucolipotoxicity and pro-inflammatory cytokines on PKR activation; (2) the effects of PKR on proliferation of pancreatic ?-cells and its underlying mechanisms; (3) the actions of PKR on pro-proliferative effects of IGF-I and its underlying pathway. Our results provided the first evidence that PKR can be activated by glucolipitoxicity and pro-inflammatory cytokines in pancreatic ?-cells, and activated PKR significantly inhibited cell proliferation by arresting cell cycle at G1 phase. Reductions in cyclin D1 and D2 as well as increases in p27 and p53 were associated with the anti-proliferative effects of PKR, and proteasome-dependent degradation took part in the reduction of cyclin D1 and D2. Besides, PKR activation abrogated the pro-proliferative effects of IGF-I by activating JNK and disrupting IRS1/PI3K/Akt signaling pathway. These findings indicate that the anti-proliferative actions of PKR on pancreatic ?-cells may contribute to the pathogenesis of T2DM.

  18. Inhibition of Hsp27 Radiosensitizes Head-and-Neck Cancer by Modulating Deoxyribonucleic Acid Repair

    SciTech Connect (OSTI)

    Guttmann, David M.; Hart, Lori; Du, Kevin; Seletsky, Andrew; Koumenis, Constantinos

    2013-09-01

    Purpose: To present a novel method of tumor radiosensitization through Hsp27 knockdown using locked nucleic acid (LNA) and to investigate the role of Hsp27 in DNA double strand break (DSB) repair. Methods and Materials: Clonogenic survival assays, immunoblotting, the proximity ligation assay, and ?H2AX foci analysis were conducted in SQ20B and FaDu human head-and-neck cancer cell lines treated with Hsp27 LNA and Hsp27 short hairpin RNA (shRNA). Additionally, nude mice with FaDu flank tumors were treated with fractionated radiation therapy after pretreatment with Hsp27 LNA and monitored for tumor growth. Results: Hsp27 LNA and Hsp27 shRNA radiosensitized head-and-neck cancer cell lines in an Hsp27-dependent manner. Ataxia-Telangectasia Mutated-mediated DNA repair signaling was impaired in irradiated cells with Hsp27 knockdown. ATM kinase inhibition abrogated the radiosensitizing effect of Hsp27. Furthermore, Hsp27 LNA and shRNA both attenuated DNA repair kinetics after radiation, and Hsp27 was found to colocalize with ATM in both untreated and irradiated cells. Last, combined radiation and Hsp27 LNA treatment in tumor xenografts in nude mice suppressed tumor growth compared with either treatment alone. Conclusions: These results support a radiosensitizing property of Hsp27 LNA in vitro and in vivo, implicate Hsp27 in double strand break repair, and suggest that Hsp27 LNA might eventually serve as an effective clinical agent in the radiotherapy of head-and-neck cancer.

  19. Phosphoramide mustard exposure induces DNA adduct formation and the DNA damage repair response in rat ovarian granulosa cells

    SciTech Connect (OSTI)

    Ganesan, Shanthi Keating, Aileen F.

    2015-02-01

    Phosphoramide mustard (PM), the ovotoxic metabolite of the anti-cancer agent cyclophosphamide (CPA), destroys rapidly dividing cells by forming NOR-G-OH, NOR-G and G-NOR-G adducts with DNA, potentially leading to DNA damage. A previous study demonstrated that PM induces ovarian DNA damage in rat ovaries. To investigate whether PM induces DNA adduct formation, DNA damage and induction of the DNA repair response, rat spontaneously immortalized granulosa cells (SIGCs) were treated with vehicle control (1% DMSO) or PM (3 or 6 μM) for 24 or 48 h. Cell viability was reduced (P < 0.05) after 48 h of exposure to 3 or 6 μM PM. The NOR-G-OH DNA adduct was detected after 24 h of 6 μM PM exposure, while the more cytotoxic G-NOR-G DNA adduct was formed after 48 h by exposure to both PM concentrations. Phosphorylated H2AX (γH2AX), a marker of DNA double stranded break occurrence, was also increased by PM exposure, coincident with DNA adduct formation. Additionally, induction of genes (Atm, Parp1, Prkdc, Xrcc6, and Brca1) and proteins (ATM, γH2AX, PARP-1, PRKDC, XRCC6, and BRCA1) involved in DNA repair were observed in both a time- and dose-dependent manner. These data support that PM induces DNA adduct formation in ovarian granulosa cells, induces DNA damage and elicits the ovarian DNA repair response. - Highlights: • PM forms ovarian DNA adducts. • DNA damage marker γH2AX increased by PM exposure. • PM induces ovarian DNA double strand break repair.

  20. Chemical repair of base lesions, AP-sites, and strand breaks on plasmid DNA in dilute aqueous solution by ascorbic acid

    SciTech Connect (OSTI)

    Hata, Kuniki; Advanced Science Research Center, Japan Atomic Energy Agency, 2-4 Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1195 ; Urushibara, Ayumi; Yamashita, Shinichi; Shikazono, Naoya; Yokoya, Akinari; Katsumura, Yosuke; Nuclear Professional School, School of Engineering, The University of Tokyo, 2-22 Shirakatashirane, Tokai-mura, Naka-gun, Ibaraki 319-1188

    2013-05-03

    Highlights: We report a novel mechanism of radiation protection of DNA by chemical activity of ascorbic acid. The chemical repair of DNA damage was revealed using biochemical assay and chemical kinetics analysis. We found that ascorbic acid significantly repairs precursors of nucleobase lesions and abasic sites. However, ascorbic acid seldom repairs precursors of DNA-strand breaks. -- Abstract: We quantified the damage yields produced in plasmid DNA by ?-irradiation in the presence of low concentrations (10100 ?M) of ascorbic acid, which is a major antioxidant in living systems, to clarify whether it chemically repairs radiation damage in DNA. The yield of DNA single strand breaks induced by irradiation was analyzed with agarose gel electrophoresis as conformational changes in closed circular plasmids. Base lesions and abasic sites were also observed as additional conformational changes by treating irradiated samples with glycosylase proteins. By comparing the suppression efficiencies to the induction of each DNA lesion, in addition to scavenging of the OH radicals derived from water radiolysis, it was found that ascorbic acid promotes the chemical repair of precursors of AP-sites and base lesions more effectively than those of single strand breaks. We estimated the efficiency of the chemical repair of each lesion using a kinetic model. Approximately 5060% of base lesions and AP-sites were repaired by 10 ?M ascorbic acid, although strand breaks were largely unrepaired by ascorbic acid at low concentrations. The methods in this study will provide a route to understanding the mechanistic aspects of antioxidant activity in living systems.

  1. Mutations Abrogating VP35 Interaction with Double-Stranded RNA Render Ebola Virus Avirulent in Guinea Pigs

    SciTech Connect (OSTI)

    Prins, Kathleen C.; Delpeut, Sebastien; Leung, Daisy W.; Reynard, Olivier; Volchkova, Valentina A.; Reid, St. Patrick; Ramanan, Parameshwaran; Cárdenas, Washington B.; Amarasinghe, Gaya K.; Volchkov, Viktor E.; Basler, Christopher F.

    2010-10-11

    Ebola virus (EBOV) protein VP35 is a double-stranded RNA (dsRNA) binding inhibitor of host interferon (IFN)-{alpha}/{beta} responses that also functions as a viral polymerase cofactor. Recent structural studies identified key features, including a central basic patch, required for VP35 dsRNA binding activity. To address the functional significance of these VP35 structural features for EBOV replication and pathogenesis, two point mutations, K319A/R322A, that abrogate VP35 dsRNA binding activity and severely impair its suppression of IFN-{alpha}/{beta} production were identified. Solution nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography reveal minimal structural perturbations in the K319A/R322A VP35 double mutant and suggest that loss of basic charge leads to altered function. Recombinant EBOVs encoding the mutant VP35 exhibit, relative to wild-type VP35 viruses, minimal growth attenuation in IFN-defective Vero cells but severe impairment in IFN-competent cells. In guinea pigs, the VP35 mutant virus revealed a complete loss of virulence. Strikingly, the VP35 mutant virus effectively immunized animals against subsequent wild-type EBOV challenge. These in vivo studies, using recombinant EBOV viruses, combined with the accompanying biochemical and structural analyses directly correlate VP35 dsRNA binding and IFN inhibition functions with viral pathogenesis. Moreover, these studies provide a framework for the development of antivirals targeting this critical EBOV virulence factor.

  2. Dimer monomer transition and dimer re-formation play important role for ATM cellular function during DNA repair

    SciTech Connect (OSTI)

    Du, Fengxia; Zhang, Minjie; Li, Xiaohua; Yang, Caiyun; Meng, Hao; Wang, Dong; Chang, Shuang; Xu, Ye; Price, Brendan; Sun, Yingli

    2014-10-03

    Highlights: • ATM phosphorylates the opposite strand of the dimer in response to DNA damage. • The PETPVFRLT box of ATM plays a key role in its dimer dissociation in DNA repair. • The dephosphorylation of ATM is critical for dimer re-formation after DNA repair. - Abstract: The ATM protein kinase, is a serine/threonine protein kinase that is recruited and activated by DNA double-strand breaks, mediates responses to ionizing radiation in mammalian cells. Here we show that ATM is held inactive in unirradiated cells as a dimer and phosphorylates the opposite strand of the dimer in response to DNA damage. Cellular irradiation induces rapid intermolecular autophosphorylation of serine 1981 that causes dimer dissociation and initiates cellular ATM kinase activity. ATM cannot phosphorylate the substrates when it could not undergo dimer monomer transition. After DNA repair, the active monomer will undergo dephosphorylation to form dimer again and dephosphorylation is critical for dimer re-formation. Our work reveals novel function of ATM dimer monomer transition and explains why ATM dimer monomer transition plays such important role for ATM cellular activity during DNA repair.

  3. Homologous recombination and non-homologous end-joining repair pathways in bovine embryos with different developmental competence

    SciTech Connect (OSTI)

    Henrique Barreta, Marcos; Laboratorio de Biotecnologia e Reproducao Animal-BioRep, Universidade Federal de Santa Maria, Santa Maria, RS ; Garziera Gasperin, Bernardo; Braga Rissi, Vitor; Cesaro, Matheus Pedrotti de; Ferreira, Rogerio; Oliveira, Joao Francisco de; Goncalves, Paulo Bayard Dias; Bordignon, Vilceu

    2012-10-01

    This study investigated the expression of genes controlling homologous recombination (HR), and non-homologous end-joining (NHEJ) DNA-repair pathways in bovine embryos of different developmental potential. It also evaluated whether bovine embryos can respond to DNA double-strand breaks (DSBs) induced with ultraviolet irradiation by regulating expression of genes involved in HR and NHEJ repair pathways. Embryos with high, intermediate or low developmental competence were selected based on the cleavage time after in vitro insemination and were removed from in vitro culture before (36 h), during (72 h) and after (96 h) the expected period of embryonic genome activation. All studied genes were expressed before, during and after the genome activation period regardless the developmental competence of the embryos. Higher mRNA expression of 53BP1 and RAD52 was found before genome activation in embryos with low developmental competence. Expression of 53BP1, RAD51 and KU70 was downregulated at 72 h and upregulated at 168 h post-insemination in response to DSBs induced by ultraviolet irradiation. In conclusion, important genes controlling HR and NHEJ DNA-repair pathways are expressed in bovine embryos, however genes participating in these pathways are only regulated after the period of embryo genome activation in response to ultraviolet-induced DSBs.

  4. Reduced repair capacity of a DNA clustered damage site comprised of 8-oxo-7,8-dihydro-2'-deoxyguanosine and 2-deoxyribonolactone results in an increased mutagenic potential of these lesions

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

    Cunniffe, Siobhan; O’Neill, Peter; Greenberg, Marc M.; Lomax, Martine E.

    2014-04-01

    A signature of ionizing radiation is the induction of DNA clustered damaged sites. Non-double strand break (DSB) clustered damage has been shown to compromise the base excision repair pathway, extending the lifetimes of the lesions within the cluster, compared to isolated lesions. This increases the likelihood the lesions persist to replication and thus increasing the mutagenic potential of the lesions within the cluster. Lesions formed by ionizing radiation include 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) and 2-deoxyribonolactone (dL). dL poses an additional challenge to the cell as it is not repaired by the short-patch base excision repair pathway. Here we show recalcitrant dL repairmore » is reflected in mutations observed when DNA containing it and a proximal 8-oxodGuo is replicated in Escherichia coli. 8-oxodGuo in close proximity to dL on the opposing DNA strand results in an enhanced frequency of mutation of the lesions within the cluster and a 20 base sequence flanking the clustered damage site in an E. coli based plasmid assay. In vitro repair of a dL lesion is reduced when compared to the repair of an abasic (AP) site and a tetrahydrofuran (THF), and this is due mainly to a reduction in the activity of polymerase β, leading to retarded FEN1 and ligase 1 activities. This study has given insights in to the biological effects of clusters containing dL.« less

  5. BREAKING BOND

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

    BREAKING BOND the Can chemistry help unbind us from fossil fuels? 1663 July 2016 21 When ... Their goal: to use chemistry to construct gasoline-like hydrocarbons from plant sugars. ...

  6. Pair breaking versus symmetry breaking: Origin of the Raman modes...

    Office of Scientific and Technical Information (OSTI)

    Pair breaking versus symmetry breaking: Origin of the Raman modes in superconducting cuprates Citation Details In-Document Search Title: Pair breaking versus symmetry breaking:...

  7. Turbine repair process, repaired coating, and repaired turbine component

    SciTech Connect (OSTI)

    Das, Rupak; Delvaux, John McConnell; Garcia-Crespo, Andres Jose

    2015-11-03

    A turbine repair process, a repaired coating, and a repaired turbine component are disclosed. The turbine repair process includes providing a turbine component having a higher-pressure region and a lower-pressure region, introducing particles into the higher-pressure region, and at least partially repairing an opening between the higher-pressure region and the lower-pressure region with at least one of the particles to form a repaired turbine component. The repaired coating includes a silicon material, a ceramic matrix composite material, and a repaired region having the silicon material deposited on and surrounded by the ceramic matrix composite material. The repaired turbine component a ceramic matrix composite layer and a repaired region having silicon material deposited on and surrounded by the ceramic matrix composite material.

  8. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Nancy Porter; Mike Sullivan; Chris Neary

    2003-05-01

    The two broad categories of deposited weld metal repair and fiber-reinforced composite repair technologies were reviewed for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Preliminary test programs were developed for both deposited weld metal repairs and for fiber-reinforced composite repair. To date, all of the experimental work pertaining to the evaluation of potential repair methods has focused on fiber-reinforced composite repairs. Hydrostatic testing was also conducted on four pipeline sections with simulated corrosion damage: two with composite liners and two without.

  9. Breaking the Bond

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

    Breaking the Bond 1663 Los Alamos science and technology magazine Latest Issue:July 2016 past issues All Issues » submit Breaking the Bond Can chemistry help unbind us from fossil fuels? July 21, 2016 info graphic gas pump Accelerating toward a more sustainable future: gas pumps may someday soon contain bio-gasoline made from plants. We are condensing millions of years of fossilization into a few chemical reactions. Fossil fuels are a finite resource. Unfortunately, the existing global

  10. Rapid road repair vehicle

    DOE Patents [OSTI]

    Mara, L.M.

    1998-05-05

    Disclosed is a rapid road repair vehicle capable of moving over a surface to be repaired at near normal posted traffic speeds to scan for and find at the high rate of speed, imperfections in the pavement surface, prepare the surface imperfection for repair by air pressure and vacuum cleaning, applying a correct amount of the correct patching material to effect the repair, smooth the resulting repaired surface, and catalog the location and quality of the repairs for maintenance records of the road surface. The rapid road repair vehicle can repair surface imperfections at lower cost, improved quality, at a higher rate of speed than was not heretofor possible, with significantly reduced exposure to safety and health hazards associated with this kind of road repair activities in the past. 2 figs.

  11. Rapid road repair vehicle

    DOE Patents [OSTI]

    Mara, Leo M.

    1998-01-01

    Disclosed is a rapid road repair vehicle capable of moving over a surface to be repaired at near normal posted traffic speeds to scan for and find an the high rate of speed, imperfections in the pavement surface, prepare the surface imperfection for repair by air pressure and vacuum cleaning, applying a correct amount of the correct patching material to effect the repair, smooth the resulting repaired surface, and catalog the location and quality of the repairs for maintenance records of the road surface. The rapid road repair vehicle can repair surface imperfections at lower cost, improved quality, at a higher rate of speed than was was heretofor possible, with significantly reduced exposure to safety and health hazards associated with this kind of road repair activities in the past.

  12. Service and Repair Work

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

    service and repair work Service and Repair Work Whenever on-site service or repair work needs to be done, a Procurement Work Sheet (PWS) must be completed, and possibly an IWS, authorized and released. PWS is required for service work even if there are no apparent hazards. PWS is required for work in Jupiter Laser Facility even if you have a PWS for service/repairs in another location. To complete a PWS for service work in Jupiter Laser Facility, please contact Sean Holte (2-3905, pager #05312).

  13. Repair of hydroprocessing reactors

    SciTech Connect (OSTI)

    Niccolls, E.H.; Imgram, A.G.; Bagdasarian, A.J.

    1995-12-01

    In this paper the authors very briefly review the types of damage observed and repairs performed in hydroprocessing reactors. The authors will summarize the fundamental damage mechanisms, and where in the reactors they have needed to make repairs over the years. The era from the 1960`s through about 1990 will be briefly discussed. They describe in more detail repairs undertaken in the 1990`s. Finally, they will note important technical issues their industry faces regarding repairs, and the long term reliable operation of these vessels.

  14. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Bill Bruce; Nancy Porter; George Ritter; Matt Boring; Mark Lozev; Ian Harris; Bill Mohr; Dennis Harwig; Robin Gordon; Chris Neary; Mike Sullivan

    2005-07-20

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without

  15. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-12-31

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without

  16. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-08-17

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Principal conclusions from a survey of natural gas transmission industry pipeline operators can be summarized in terms of the following performance requirements for internal repair: (1) Use of internal repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling when a new bore must be created to solve a leak or other problem. (3) Typical travel distances can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). All three groups require pig-based systems. A despooled umbilical system would suffice for the first two groups which represents 81% of survey respondents. The third group would require an onboard self-contained power unit for propulsion and welding/liner repair energy needs. (4) The most common size range for 80% to 90% of operators surveyed is 508 mm (20 in.) to 762 mm (30 in.), with 95% using 558.8 mm (22 in.) pipe. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners

  17. EUVL Mask Blank Repair

    SciTech Connect (OSTI)

    Barty, A; Mirkarimi, P; Stearns, D G; Sweeney, D; Chapman, H N; Clift, M; Hector, S; Yi, M

    2002-05-22

    EUV mask blanks are fabricated by depositing a reflective Mo/Si multilayer film onto super-polished substrates. Small defects in this thin film coating can significantly alter the reflected field and introduce defects in the printed image. Ideally one would want to produce defect-free mask blanks; however, this may be very difficult to achieve in practice. One practical way to increase the yield of mask blanks is to effectively repair multilayer defects, and to this effect they present two complementary defect repair strategies for use on multilayer-coated EUVL mask blanks. A defect is any area on the mask which causes unwanted variations in EUV dose in the aerial image obtained in a printing tool, and defect repair is correspondingly defined as any strategy that renders a defect unprintable during exposure. The term defect mitigation can be adopted to describe any strategy which renders a critical defect non-critical when printed, and in this regard a non-critical defect is one that does not adversely affect device function. Defects in the patterned absorber layer consist of regions where metal, typically chrome, is unintentionally added or removed from the pattern leading to errors in the reflected field. There currently exists a mature technology based on ion beam milling and ion beam assisted deposition for repairing defects in the absorber layer of transmission lithography masks, and it is reasonable to expect that this technology will be extended to the repair of absorber defects in EUVL masks. However, techniques designed for the repair of absorber layers can not be directly applied to the repair of defects in the mask blank, and in particular the multilayer film. In this paper they present for the first time a new technique for the repair of amplitude defects as well as recent results on the repair of phase defects.

  18. Rapid road repair vehicle

    DOE Patents [OSTI]

    Mara, Leo M.

    1999-01-01

    Disclosed are improvments to a rapid road repair vehicle comprising an improved cleaning device arrangement, two dispensing arrays for filling defects more rapidly and efficiently, an array of pre-heaters to heat the road way surface in order to help the repair material better bond to the repaired surface, a means for detecting, measuring, and computing the number, location and volume of each of the detected surface imperfection, and a computer means schema for controlling the operation of the plurality of vehicle subsystems. The improved vehicle is, therefore, better able to perform its intended function of filling surface imperfections while moving over those surfaces at near normal traffic speeds.

  19. INTERNAL REPAIR OF PIPELINES

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; Nancy Porter; Mike Sullivan; Chris Neary

    2004-04-12

    The two broad categories of deposited weld metal repair and fiber-reinforced composite liner repair technologies were reviewed for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Preliminary test programs were developed for both deposited weld metal repair and for fiber-reinforced composite liner repair. Evaluation trials have been conducted using a modified fiber-reinforced composite liner provided by RolaTube and pipe sections without liners. All pipe section specimens failed in areas of simulated damage. Pipe sections containing fiber-reinforced composite liners failed at pressures marginally greater than the pipe sections without liners. The next step is to evaluate a liner material with a modulus of elasticity approximately 95% of the modulus of elasticity for steel. Preliminary welding parameters were developed for deposited weld metal repair in preparation of the receipt of Pacific Gas & Electric's internal pipeline welding repair system (that was designed specifically for 559 mm (22 in.) diameter pipe) and the receipt of 559 mm (22 in.) pipe sections from Panhandle Eastern. The next steps are to transfer welding parameters to the PG&E system and to pressure test repaired pipe sections to failure. A survey of pipeline operators was conducted to better understand the needs and performance requirements of the natural gas transmission industry regarding internal repair. Completed surveys contained the following principal conclusions: (1) Use of internal weld repair is most attractive for river crossings, under other bodies of water, in difficult soil conditions, under highways, under congested intersections, and under railway crossings. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling (HDD) when a new bore must be created to

  20. Aircraft Propeller Hub Repair

    SciTech Connect (OSTI)

    Muth, Thomas R.; Peter, William H.

    2015-02-13

    The team performed a literature review, conducted residual stress measurements, performed failure analysis, and demonstrated a solid state additive manufacturing repair technique on samples removed from a scrapped propeller hub. The team evaluated multiple options for hub repair that included existing metal buildup technologies that the Federal Aviation Administration (FAA) has already embraced, such as cold spray, high velocity oxy-fuel deposition (HVOF), and plasma spray. In addition the team helped Piedmont Propulsion Systems, LLC (PPS) evaluate three potential solutions that could be deployed at different stages in the life cycle of aluminum alloy hubs, in addition to the conventional spray coating method for repair. For new hubs, a machining practice to prevent fretting with the steel drive shaft was recommended. For hubs that were refurbished with some material remaining above the minimal material condition (MMC), a silver interface applied by an electromagnetic pulse additive manufacturing method was recommended. For hubs that were at or below the MMC, a solid state additive manufacturing technique using ultrasonic welding (UW) of thin layers of 7075 aluminum to the hub interface was recommended. A cladding demonstration using the UW technique achieved mechanical bonding of the layers showing promise as a viable repair method.

  1. The influence of TRP53 in the dose response of radiation-induced apoptosis, DNA repair and genomic stability in murine haematopoietic cells

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

    Lemon, Jennifer A.; Taylor, Kristina; Verdecchia, Kyle; Phan, Nghi; Boreham, Douglas R.

    2014-01-01

    Apoptotic and DNA damage endpoints are frequently used as surrogate markers of cancer risk, and have been well-studied in the Trp53+/- mouse model. We report the effect of differing Trp53 gene status on the dose response of ionizing radiation exposures (0.01-2 Gy), with the unique perspective of determining if effects of gene status remain at extended time points. Here we report no difference in the dose response for radiation-induced DNA double-strand breaks in bone marrow and genomic instability (MN-RET levels) in peripheral blood, between wild-type (Trp53+/+) and heterozygous (Trp53+/-) mice. The dose response for Trp53+/+ mice showed higher initial levelsmore » of radiation-induced lymphocyte apoptosis relative to Trp53+/- between 0 and 1 Gy. Although this trend was observed up to 12 hours post-irradiation, both genotypes ultimately reached the same level of apoptosis at 14 hours, suggesting the importance of late-onset p53-independent apoptotic responses in this mouse model. Expected radiation-induced G1 cell cycle delay was observed in Trp53+/+ but not Trp53+/-. Although p53 has an important role in cancer risk, we have shown its influence on radiation dose response can be temporally variable. This research highlights the importance of caution when using haematopoietic endpoints as surrogates to extrapolate radiation-induced cancer risk estimation.« less

  2. DNB CP - Steamline Break Analysis

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

    5-000 DNB Challenge Problem Progress - Steamline Break Analysis Industry Council Meeting April 12, 2016 2 CASL-U-2016-1085-000 Outline * DNB CP to Meet Industry's Needs * PWR Steamline Break (SLB) Analysis Overview * Ongoing FY16 Activities on SLB Analysis 3 CASL-U-2016-1085-000 Departure from Nucleate Boiling (DNB) * DNB also referred to as Critical Heat Flux (CHF) - Local clad surface dryout causes dramatic reduction in heat transfer during transients - One of safety and regulatory acceptance

  3. Breaking the Biological Barriers to Cellulosic Ethanol, June...

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

    Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 Breaking the Biological Barriers to Cellulosic ...

  4. Give Young Scientists a Break

    SciTech Connect (OSTI)

    Wiley, H. S.

    2009-11-01

    There has been much concern about the impact of tight funding on the careers of young scientists. When only a small percentage of grants are approved, even the smallest problem or error with an application can push it out of the funding range. Unfortunately, the relative lack of grant writing skills by new investigators often has this effect. To avoid a situation where only experienced investigators with polished writing skills are funded, the National Institutes of Health has instituted a more generous ranking scale for new investigators. Not surprisingly, some senior investigators have protested, calling it reverse discrimination. I say that their anger is misplaced. New investigators do deserve a break.

  5. New Technologies for Repairing Aging Cables in Nuclear Power Plants

    SciTech Connect (OSTI)

    Simmons, Kevin L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westman, Matthew P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-09-11

    The goal of this project is to demonstrate a proof-of-concept for a technique to repair aging cables that have been subjected to degradation associated with long-term thermal and radiation exposure in nuclear power plants. The physical degradation of the aging cables manifests itself primarily as cracking and increased brittleness of the polymeric electrical insulation. Therefore, the proposed cable-repair concept comprises development of techniques to impart a softening agent within the deteriorated polymer insulation jacket so as to regain the ability of the insulation to stretch without failing and possibly to heal existing cracks in the insulation. Our approach is to use commercially available ethylene-propylene rubber (EPR) as the relevant test material, demonstrate the adsorption of chemical treatments in the EPR and quantify changes in resulting physical and mechanical properties. EPR cable samples have been thermally treated in air to produce specimens corresponding to the full range of cable age-performance points from new (>350% elongation at break) to end-of-life (<50% elongation at break). The current focus is on two chemical treatments selected as candidates for restoring age-related cable elasticity loss: a rubber plasticizer and a reactive silane molecule. EPR specimens of 200, 150, 100, and 50% elongation at break have been soaked in the candidate chemical treatments and the kinetics of chemical uptake, measured by change in mass of the samples, has been determined. Mechanical properties as a function of aging and chemical treatment have been measured including ultimate tensile strength, tensile modulus at 50% strain, elongation at break, and storage modulus. Dimensional changes with treatment and changes in glass transition temperature were also investigated. These ongoing experiments are expected to provide insight into the physical-chemical nature of the effect of thermal degradation on EPR rejuvenation limits and to advance novel methods for

  6. Total-derivative supersymmetry breaking

    SciTech Connect (OSTI)

    Haba, Naoyuki; Uekusa, Nobuhiro

    2010-05-15

    On an interval compactification in supersymmetric theory, boundary conditions for bulk fields must be treated carefully. If they are taken arbitrarily following the requirement that a theory is supersymmetric, the conditions could give redundant constraints on the theory. We construct a supersymmetric action integral on an interval by introducing brane interactions with which total-derivative terms under the supersymmetry transformation become zero due to a cancellation. The variational principle leads equations of motion and also boundary conditions for bulk fields, which determine boundary values of bulk fields. By estimating mass spectrum, spontaneous supersymmetry breaking in this simple setup can be realized in a new framework. This supersymmetry breaking does not induce a massless R axion, which is favorable for phenomenology. It is worth noting that fermions in hyper-multiplet, gauge bosons, and the fifth-dimensional component of gauge bosons can have zero-modes (while the other components are all massive as Kaluza-Klein modes), which fits the gauge-Higgs unification scenarios.

  7. Vanadium catalysts break down biomass for fuels

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

    break down biomass into useful components Due to diminishing petroleum reserves, non-food biomass (lignocellulose) is an attractive alternative as a feedstock for the...

  8. NREL: Technology Transfer - Popular Mechanics: Scientists Break...

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

    Popular Mechanics: Scientists Break This Virtual Power Grid to Save the Real One July 27, 2015 Popular Mechanics describes how NREL's Energy Systems Integration Facility (ESIF)...

  9. new chemistry to break down cell walls

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

    new chemistry to break down cell walls - Sandia Energy Energy Search Icon Sandia Home ... Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power ...

  10. Inspect and Repair Steam Traps

    SciTech Connect (OSTI)

    Not Available

    2006-01-01

    This revised ITP tip sheet on inspecting and repairing steam traps provide how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  11. Motor Repair Tech Brief | Department of Energy

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

    Repair Tech Brief Motor Repair Tech Brief This Tech Brief answers: Why do motors fail? When should you repair instead of replace? And how can reliability and efficiency be assured in a repair? Motor Repair Tech Brief (March 2000) (941.96 KB) More Documents & Publications Extend the Operating Life of Your Motor Service Center Evaluation Guide Premium Efficiency Motor Selection and Application Guide - A Handbook for Industry

  12. Method of preparing and applying single stranded DNA probes to double stranded target DNAs in situ

    DOE Patents [OSTI]

    Gray, Joe W.; Pinkel, Daniel

    1991-01-01

    A method is provided for producing single stranded non-self-complementary nucleic acid probes, and for treating target DNA for use therewith. Probe is constructed by treating DNA with a restriction enzyme and an exonuclease to form template/primers for a DNA polymerase. The digested strand is resynthesized in the presence of labeled nucleoside triphosphate precursor. Labeled single stranded fragments are separated from the resynthesized fragments to form the probe. Target DNA is treated with the same restriction enzyme used to construct the probe, and is treated with an exonuclease before application of the probe. The method significantly increases the efficiency and specificity of hybridization mixtures by increasing effective probe concentration by eliminating self-hybridization between both probe and target DNAs, and by reducing the amount of target DNA available for mismatched hybridizations.

  13. Method of preparing and applying single stranded DNA probes to double stranded target DNAs in situ

    DOE Patents [OSTI]

    Gray, J.W.; Pinkel, D.

    1991-07-02

    A method is provided for producing single stranded non-self-complementary nucleic acid probes, and for treating target DNA for use therewith. The probe is constructed by treating DNA with a restriction enzyme and an exonuclease to form template/primers for a DNA polymerase. The digested strand is resynthesized in the presence of labeled nucleoside triphosphate precursor. Labeled single stranded fragments are separated from the resynthesized fragments to form the probe. Target DNA is treated with the same restriction enzyme used to construct the probe, and is treated with an exonuclease before application of the probe. The method significantly increases the efficiency and specificity of hybridization mixtures by increasing effective probe concentration by eliminating self-hybridization between both probe and target DNAs, and by reducing the amount of target DNA available for mismatched hybridizations. No Drawings

  14. Dyes designed for high sensitivity detection of double-stranded DNA

    DOE Patents [OSTI]

    Glazer, Alexander N.; Benson, Scott C.

    1998-01-01

    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.

  15. Dyes designed for high sensitivity detection of double-stranded DNA

    DOE Patents [OSTI]

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

    1998-07-21

    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.

  16. Dyes designed for high sensitivity detection of double-stranded DNA

    DOE Patents [OSTI]

    Glazer, Alexander N.; Benson, Scott C.

    2000-01-01

    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.

  17. Dyes designed for high sensitivity detection of double-stranded DNA

    DOE Patents [OSTI]

    Glazer, Alexander N.; Benson, Scott C.

    1994-01-01

    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.

  18. The influence of TRP53 in the dose response of radiation-induced apoptosis, DNA repair and genomic stability in murine haematopoietic cells

    SciTech Connect (OSTI)

    Lemon, Jennifer A.; Taylor, Kristina; Verdecchia, Kyle; Phan, Nghi; Boreham, Douglas R.

    2014-01-01

    Apoptotic and DNA damage endpoints are frequently used as surrogate markers of cancer risk, and have been well-studied in the Trp53+/- mouse model. We report the effect of differing Trp53 gene status on the dose response of ionizing radiation exposures (0.01-2 Gy), with the unique perspective of determining if effects of gene status remain at extended time points. Here we report no difference in the dose response for radiation-induced DNA double-strand breaks in bone marrow and genomic instability (MN-RET levels) in peripheral blood, between wild-type (Trp53+/+) and heterozygous (Trp53+/-) mice. The dose response for Trp53+/+ mice showed higher initial levels of radiation-induced lymphocyte apoptosis relative to Trp53+/- between 0 and 1 Gy. Although this trend was observed up to 12 hours post-irradiation, both genotypes ultimately reached the same level of apoptosis at 14 hours, suggesting the importance of late-onset p53-independent apoptotic responses in this mouse model. Expected radiation-induced G1 cell cycle delay was observed in Trp53+/+ but not Trp53+/-. Although p53 has an important role in cancer risk, we have shown its influence on radiation dose response can be temporally variable. This research highlights the importance of caution when using haematopoietic endpoints as surrogates to extrapolate radiation-induced cancer risk estimation.

  19. Selected Bibliography on Electric Motor Repair | Department of...

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

    Selected Bibliography on Electric Motor Repair Selected Bibliography on Electric Motor Repair The following series of repair documents related to electric motors were produced by...

  20. A mutational signature in gastric cancer suggests therapeutic strategies

    SciTech Connect (OSTI)

    Alexandrov, Ludmil B.; Nik-Zainal, Serena; Siu, Hoi Cheong; Leung, Suet Yi; Stratton, Michael R.

    2015-10-29

    Targeting defects in the DNA repair machinery of neoplastic cells, for example, those due to inactivating BRCA1 and/or BRCA2 mutations, has been used for developing new therapies in certain types of breast, ovarian and pancreatic cancers. Recently, a mutational signature was associated with failure of double-strand DNA break repair by homologous recombination based on its high mutational burden in samples harbouring BRCA1 or BRCA2 mutations. In pancreatic cancer, all responders to platinum therapy exhibit this mutational signature including a sample that lacked any defects in BRCA1 or BRCA2. Here, we examine 10,250 cancer genomes across 36 types of cancer and demonstrate that, in addition to breast, ovarian and pancreatic cancers, gastric cancer is another cancer type that exhibits this mutational signature. Furthermore, our results suggest that 7–12% of gastric cancers have defective double-strand DNA break repair by homologous recombination and may benefit from either platinum therapy or PARP inhibitors.

  1. A mutational signature in gastric cancer suggests therapeutic strategies

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

    Alexandrov, Ludmil B.; Nik-Zainal, Serena; Siu, Hoi Cheong; Leung, Suet Yi; Stratton, Michael R.

    2015-10-29

    Targeting defects in the DNA repair machinery of neoplastic cells, for example, those due to inactivating BRCA1 and/or BRCA2 mutations, has been used for developing new therapies in certain types of breast, ovarian and pancreatic cancers. Recently, a mutational signature was associated with failure of double-strand DNA break repair by homologous recombination based on its high mutational burden in samples harbouring BRCA1 or BRCA2 mutations. In pancreatic cancer, all responders to platinum therapy exhibit this mutational signature including a sample that lacked any defects in BRCA1 or BRCA2. Here, we examine 10,250 cancer genomes across 36 types of cancer andmore » demonstrate that, in addition to breast, ovarian and pancreatic cancers, gastric cancer is another cancer type that exhibits this mutational signature. Furthermore, our results suggest that 7–12% of gastric cancers have defective double-strand DNA break repair by homologous recombination and may benefit from either platinum therapy or PARP inhibitors.« less

  2. A Fullerene that Breaks the Rules

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

    A Fullerene that Breaks the Rules A Fullerene that Breaks the Rules Print Tuesday, 28 April 2015 00:00 In the 30 years since the discovery of the classic fullerene "buckyball" of 60 carbon atoms, scientists have found many variations on the fullerene theme: carbon nanotubes (elongated buckyballs), endohedral fullerenes (buckyballs with molecules inside), and even carbon "peapods" (nanotubes with buckyballs inside). Within this great diversity, however, certain rules emerged.

  3. Bending-induced Symmetry Breaking of Lithiation in Germanium...

    Office of Scientific and Technical Information (OSTI)

    Bending-induced Symmetry Breaking of Lithiation in Germanium Nanowires Citation Details In-Document Search Title: Bending-induced Symmetry Breaking of Lithiation in Germanium ...

  4. Novel Thermal Break with Simplified Manufacturing for R7 Commercial...

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

    Thermal Break with Simplified Manufacturing for R7 Commercial Windows Novel Thermal Break with Simplified Manufacturing for R7 Commercial Windows Lead Performer: Alcoa - ...

  5. Break-out Discussion i: Modeling Consumer Behavior Residential...

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

    Break-out Discussion i: Modeling Consumer Behavior Residential Scale Break-out Discussion i: Modeling Consumer Behavior Residential Scale This presentaion summarizes the ...

  6. Chiral symmetry and chiral-symmetry breaking

    SciTech Connect (OSTI)

    Peskin, M.E.

    1982-12-01

    These lectures concern the dynamics of fermions in strong interaction with gauge fields. Systems of fermions coupled by gauge forces have a very rich structure of global symmetries, which are called chiral symmetries. These lectures will focus on the realization of chiral symmetries and the causes and consequences of thier spontaneous breaking. A brief introduction to the basic formalism and concepts of chiral symmetry breaking is given, then some explicit calculations of chiral symmetry breaking in gauge theories are given, treating first parity-invariant and then chiral models. These calculations are meant to be illustrative rather than accurate; they make use of unjustified mathematical approximations which serve to make the physics more clear. Some formal constraints on chiral symmetry breaking are discussed which illuminate and extend the results of our more explicit analysis. Finally, a brief review of the phenomenological theory of chiral symmetry breaking is presented, and some applications of this theory to problems in weak-interaction physics are discussed. (WHK)

  7. Workshop on electroweak symmetry breaking: proceedings

    SciTech Connect (OSTI)

    Hinchliffe, I.

    1984-10-01

    A theoretical workshop on electroweak symmetry breaking at the Superconducting Supercollider was held at Lawrence Berkeley Laboratory, June 4-22, 1984. The purpose of the workshop was to focus theoretical attention on the ways in which experimentation at the SSC could reveal manifestations of the phenomenon responsible for electroweak symmetry breaking. This issue represents, at present, the most compelling scientific argument for the need to explore the energy region to be made accessible by the SSC, and a major aim of the workshop was to involve a broad cross section of particle theorists in the ongoing process of sharpening the requirements for both accelerator and detector design that will ensure detection and identification of meaningful signals, whatever form the electroweak symmetry breaking phenomenon should actually take. Separate entries were prepared for the data base for the papers presented.

  8. Plasma induced DNA damage: Comparison with the effects of ionizing radiation

    SciTech Connect (OSTI)

    Lazovi?, S.; Maleti?, D.; Pua?, N.; Malovi?, G.; Petrovi?, Z. Lj.; Leskovac, A.; Filipovi?, J.; Joksi?, G.

    2014-09-22

    We use human primary fibroblasts for comparing plasma and gamma rays induced DNA damage. In both cases, DNA strand breaks occur, but of fundamentally different nature. Unlike gamma exposure, contact with plasma predominantly leads to single strand breaks and base-damages, while double strand breaks are mainly consequence of the cell repair mechanisms. Different cell signaling mechanisms are detected confirming this (ataxia telangiectasia mutated - ATM and ataxia telangiectasia and Rad3 related - ATR, respectively). The effective plasma doses can be tuned to match the typical therapeutic doses of 2?Gy. Tailoring the effective dose through plasma power and duration of the treatment enables safety precautions mainly by inducing apoptosis and consequently reduced frequency of micronuclei.

  9. Haier Repair Confusion Resolved | Department of Energy

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

    Haier Repair Confusion Resolved Haier Repair Confusion Resolved April 26, 2010 - 12:28pm Addthis On January 7, 2010, DOE entered into a Consent Decree with Haier America regarding a problem with four models of Haier freezers that resulted in those freezers not achieving their advertised energy efficiency. DOE recently became aware that some consumers eligible for repairs were incorrectly told that they were not eligible. Haier has resolved the problem, and consumers are encouraged to contact

  10. Distribution System Audits, Leak Detection, and Repair: Kirtland Air Force Base Leak Detection and Repair Program

    SciTech Connect (OSTI)

    2009-01-14

    Water Best Management Practice #3 Fact Seet: Outlines how a leak detection and repair program helped Kirtland Air Force Base perform distribution system audits, leak detection, and repair to conserve water site-wide.

  11. Cadmium sulfate and CdTe-quantum dots alter DNA repair in zebrafish (Danio rerio) liver cells

    SciTech Connect (OSTI)

    Tang, Song; Cai, Qingsong; Chibli, Hicham; Allagadda, Vinay; Nadeau, Jay L.; Mayer, Gregory D.

    2013-10-15

    Increasing use of quantum dots (QDs) makes it necessary to evaluate their toxicological impacts on aquatic organisms, since their contamination of surface water is inevitable. This study compares the genotoxic effects of ionic Cd versus CdTe nanocrystals in zebrafish hepatocytes. After 24 h of CdSO{sub 4} or CdTe QD exposure, zebrafish liver (ZFL) cells showed a decreased number of viable cells, an accumulation of Cd, an increased formation of reactive oxygen species (ROS), and an induction of DNA strand breaks. Measured levels of stress defense and DNA repair genes were elevated in both cases. However, removal of bulky DNA adducts by nucleotide excision repair (NER) was inhibited with CdSO{sub 4} but not with CdTe QDs. The adverse effects caused by acute exposure of CdTe QDs might be mediated through differing mechanisms than those resulting from ionic cadmium toxicity, and studying the effects of metallic components may be not enough to explain QD toxicities in aquatic organisms. - Highlights: Both CdSO{sub 4} and CdTe QDs lead to cell death and Cd accumulation. Both CdSO{sub 4} and CdTe QDs induce cellular ROS generation and DNA strand breaks. Both CdSO{sub 4} and CdTe QDs induce the expressions of stress defense and DNA repair genes. NER repair capacity was inhibited with CdSO{sub 4} but not with CdTe QDs.

  12. Electroweak Symmetry Breaking in Historical Perspective

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

    Quigg, Chris

    2015-10-01

    The discovery of the Higgs boson is a major milestone in our progress toward understanding the natural world. A particular aim of my review is to show how diverse ideas came together in the conception of electroweak symmetry breaking that led up to the discovery. Furthermore, I survey what we know now that we did not know before, what properties of the Higgs boson remain to be established, and what new questions we may now hope to address.

  13. Textural break foundation wall construction modules

    DOE Patents [OSTI]

    Phillips, Steven J.

    1990-01-01

    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.

  14. A Fullerene that Breaks the Rules

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

    A Fullerene that Breaks the Rules Print In the 30 years since the discovery of the classic fullerene "buckyball" of 60 carbon atoms, scientists have found many variations on the fullerene theme: carbon nanotubes (elongated buckyballs), endohedral fullerenes (buckyballs with molecules inside), and even carbon "peapods" (nanotubes with buckyballs inside). Within this great diversity, however, certain rules emerged. One such rule governed the number and placement of the

  15. A Fullerene that Breaks the Rules

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

    A Fullerene that Breaks the Rules Print In the 30 years since the discovery of the classic fullerene "buckyball" of 60 carbon atoms, scientists have found many variations on the fullerene theme: carbon nanotubes (elongated buckyballs), endohedral fullerenes (buckyballs with molecules inside), and even carbon "peapods" (nanotubes with buckyballs inside). Within this great diversity, however, certain rules emerged. One such rule governed the number and placement of the

  16. A Fullerene that Breaks the Rules

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

    A Fullerene that Breaks the Rules Print In the 30 years since the discovery of the classic fullerene "buckyball" of 60 carbon atoms, scientists have found many variations on the fullerene theme: carbon nanotubes (elongated buckyballs), endohedral fullerenes (buckyballs with molecules inside), and even carbon "peapods" (nanotubes with buckyballs inside). Within this great diversity, however, certain rules emerged. One such rule governed the number and placement of the

  17. A Fullerene that Breaks the Rules

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

    A Fullerene that Breaks the Rules Print In the 30 years since the discovery of the classic fullerene "buckyball" of 60 carbon atoms, scientists have found many variations on the fullerene theme: carbon nanotubes (elongated buckyballs), endohedral fullerenes (buckyballs with molecules inside), and even carbon "peapods" (nanotubes with buckyballs inside). Within this great diversity, however, certain rules emerged. One such rule governed the number and placement of the

  18. Cloud Properties Working Group Break Out Session

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

    Break Out Session ARM Science Team Meeting Louisville, KY 30 March 2009 The Chair's Objectives for CPWG *Maintain continuity of "base" instruments - We're building a climatology! *Advocate for sufficient programmatic support to make our measurements useful. *Better retrieval vetting framework - moving towards Cloud Properties Best Estimate *Build a stronger connection with the modeling community - Producing the products they want. CPWG Breakout Agenda 30 March 2009, 3-5 pm *3:00-3:15

  19. Breaking a Pocket of Resistance in the Fight Against Cancer

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

    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...

  20. Modulated Tool-Path (MTP) Chip Breaking System - Energy Innovation...

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

    PDF Document Publication R&D 100 award (Chip Breaking)(final).pdf (8,767 KB) Technology Marketing Summary The MTP chip breaking system is a cost-saving solution for machining ...

  1. 5-MW Dynamometer Ground Breaking | Department of Energy

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

    5-MW Dynamometer Ground Breaking 5-MW Dynamometer Ground Breaking December 19, 2011 - 3:04pm Addthis This is an excerpt from the Fourth Quarter 2011 edition of the Wind Program R&D ...

  2. Ground Breaking of Blythe Solar Power Project | Department of...

    Energy Savers [EERE]

    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 ...

  3. Search for: All records | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    ... laser-accelerated protons on human lung cancer cells.more In-vitro A549 cells are ... of DNA double-strand breaks in human cancer cells Yogo, A. ; Nishikino, M. ; Mori, M. ...

  4. Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 |

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

    Department of Energy Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 b2blowres63006.pdf (8.11 MB) More Documents & Publications Breaking the Biological Barriers to Cellulosic Ethanol, June 2006 Review of Recent Pilot Scale Cellulosic Ethanol Demonstration Biochemical Conversion: Using Hydrolysis, Fermentation, and Catalysis to Make Fuels

  5. DNA purification by triplex-affinity capture and affinity capture electrophoresis

    DOE Patents [OSTI]

    Cantor, Charles R.; Ito, Takashi; Smith, Cassandra L.

    1996-01-01

    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. DNA purification by triplex-affinity capture and affinity capture electrophoresis

    DOE Patents [OSTI]

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

    1996-01-09

    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.

  7. INTERNAL REPAIR OF PIPELINES REVIEW & EVALUATION OF INTERNAL PIPELINE REPAIR TRIALS REPORT

    SciTech Connect (OSTI)

    Robin Gordon; Bill Bruce; Ian Harris; Dennis Harwig; George Ritter; Bill Mohr; Matt Boring; Nancy Porter; Mike Sullivan; Chris Neary

    2004-09-01

    The two broad categories of fiber-reinforced composite liner repair and deposited weld metal repair technologies were reviewed and evaluated for potential application for internal repair of gas transmission pipelines. Both are used to some extent for other applications and could be further developed for internal, local, structural repair of gas transmission pipelines. Evaluation trials were conducted on pipe sections with simulated corrosion damage repaired with glass fiber-reinforced composite liners, carbon fiber-reinforced composite liners, and weld deposition. Additional un-repaired pipe sections were evaluated in the virgin condition and with simulated damage. Hydrostatic failure pressures for pipe sections repaired with glass fiber-reinforced composite liner were only marginally greater than that of pipe sections without liners, indicating that this type of liner is generally ineffective at restoring the pressure containing capabilities of pipelines. Failure pressure for pipe repaired with carbon fiber-reinforced composite liner was greater than that of the un-repaired pipe section with damage, indicating that this type of liner is effective at restoring the pressure containing capability of pipe. Pipe repaired with weld deposition failed at pressures lower than that of un-repaired pipe in both the virgin and damaged conditions, indicating that this repair technology is less effective at restoring the pressure containing capability of pipe than a carbon fiber-reinforced liner repair. Physical testing indicates that carbon fiber-reinforced liner repair is the most promising technology evaluated to-date. Development of a comprehensive test plan for this process is recommended for use in the next phase of this project.

  8. Solar Water Heating System Maintenance and Repair | Department...

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

    Water Heating System Maintenance and Repair Solar Water Heating System Maintenance and Repair Rooftop solar water heaters need regular maintenance to operate at peak efficiency. |...

  9. Leveraging Service Calls and Emergency Repairs for Energy Efficiency...

    Energy Savers [EERE]

    Service Calls and Emergency Repairs for Energy Efficiency Marketing Leveraging Service Calls and Emergency Repairs for Energy Efficiency Marketing Better Buildings Residential ...

  10. Solar Water Heating System Maintenance and Repair | Department...

    Energy Savers [EERE]

    Water Heating System Maintenance and Repair Solar Water Heating System Maintenance and Repair Rooftop solar water heaters need regular maintenance to operate at peak efficiency. | ...

  11. Breaking Barriers in Polymer Additive Manufacturing

    SciTech Connect (OSTI)

    Love, Lonnie J; Duty, Chad E; Post, Brian K; Lind, Randall F; Lloyd, Peter D; Kunc, Vlastimil; Peter, William H; Blue, Craig A

    2015-01-01

    Additive Manufacturing (AM) enables the creation of complex structures directly from a computer-aided design (CAD). There are limitations that prevent the technology from realizing its full potential. AM has been criticized for being slow and expensive with limited build size. Oak Ridge National Laboratory (ORNL) has developed a large scale AM system that improves upon each of these areas by more than an order of magnitude. The Big Area Additive Manufacturing (BAAM) system directly converts low cost pellets into a large, three-dimensional part at a rate exceeding 25 kg/h. By breaking these traditional barriers, it is possible for polymer AM to penetrate new manufacturing markets.

  12. Developments advance subsea pipelaying, inspection, repair

    SciTech Connect (OSTI)

    1997-09-15

    Recent advances in laying, inspecting, and repairing pipelines are helping to cut both costs and time. A new dredging system that employs jets to clear a subsea trench for pipelay received trials off Belgium last spring. Also, within the last year, projects in the Middle East and North Sea employed technologies that promise to make inspecting the surface of a subsea pipeline in difficult terrain easier, less time consuming, and therefore less costly. Plus, subsea repair of damaged pipelines may take less time with a new ``stabbable`` pipe connector. The paper describes jet dredging, inspection advance, support software, the North Sea site, and pipeline repair.

  13. Chip breaking system for automated machine tool

    DOE Patents [OSTI]

    Arehart, Theodore A.; Carey, Donald O.

    1987-01-01

    The invention is a rotary selectively directional valve assembly for use in an automated turret lathe for directing a stream of high pressure liquid machining coolant to the interface of a machine tool and workpiece for breaking up ribbon-shaped chips during the formation thereof so as to inhibit scratching or other marring of the machined surfaces by these ribbon-shaped chips. The valve assembly is provided by a manifold arrangement having a plurality of circumferentially spaced apart ports each coupled to a machine tool. The manifold is rotatable with the turret when the turret is positioned for alignment of a machine tool in a machining relationship with the workpiece. The manifold is connected to a non-rotational header having a single passageway therethrough which conveys the high pressure coolant to only the port in the manifold which is in registry with the tool disposed in a working relationship with the workpiece. To position the machine tools the turret is rotated and one of the tools is placed in a material-removing relationship of the workpiece. The passageway in the header and one of the ports in the manifold arrangement are then automatically aligned to supply the machining coolant to the machine tool workpiece interface for breaking up of the chips as well as cooling the tool and workpiece during the machining operation.

  14. A Guide to AC Motor Repair and Replacement

    SciTech Connect (OSTI)

    2004-03-01

    This booklet provides helpful information for making informed repair or replace decisions for electric motors.

  15. Electronic Fabrication & Repair | The Ames Laboratory

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

    Electronic Fabrication & Repair The Electronics group provides custom design and fabrication of electronic equipment.. We convert ideas into custom-finished equipment in our shop using ORCAD Schematic Capture and PCB Layout software in conjunction with our PCB machine to make prototype circuit boards in-house. Our technicians also aid in automating and controlling research project instrumentation using Texas Instruments LabView. We repair all kinds of scientific and laboratory electronic and

  16. Supersymmetry Breaking, Gauge Mediation, and the LHC

    SciTech Connect (OSTI)

    Shih, David

    2015-04-14

    Gauge mediated SUSY breaking (GMSB) is a promising class of supersymmetric models that automatically satisfies the precision constraints. Prior work of Meade, Seiberg and Shih in 2008 established the full, model-independent parameter space of GMSB, which they called "General Gauge Mediation" (GGM). During the first half of 2010-2015, Shih and his collaborators thoroughly explored the parameter space of GGM and established many well-motivated benchmark models for use by the experimentalists at the LHC. Through their work, the current constraints on GGM from LEP, the Tevatron and the LHC were fully elucidated, together with the possible collider signatures of GMSB at the LHC. This ensured that the full discovery potential for GGM could be completely realized at the LHC.

  17. Breaking Ground in Miami-Dade

    Broader source: Energy.gov [DOE]

    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 canal to the water plant where it will be mixed with digester gases.  By combining landfill and digester gases, the county will increase the amount of self-generated electricity, and reduce the county's consumption of electricity generated from fossil fuels.  

  18. Model Repair Specifications for Low Voltage Induction Motors | Department

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

    of Energy Repair Specifications for Low Voltage Induction Motors Model Repair Specifications for Low Voltage Induction Motors These Model Repair Specifications are intended to cover routine repair and rewind of low-voltage random-wound three-phase AC squirrel cage induction motors. Model Repair Specifications for Low Voltage Induction Motors (November 1999) (1.31 MB) More Documents & Publications DOE Navigant Master Presentation Improving Motor and Drive System Performance - A Sourcebook

  19. Energy and Technology Review: Unlocking the mysteries of DNA repair

    SciTech Connect (OSTI)

    Quirk, W.A.

    1993-04-01

    DNA, the genetic blueprint, has the remarkable property of encoding its own repair following diverse types of structural damage induced by external agents or normal metabolism. We are studying the interplay of DNA damaging agents, repair genes, and their protein products to decipher the complex biochemical pathways that mediate such repair. Our research focuses on repair processes that correct DNA damage produced by chemical mutagens and radiation, both ionizing and ultraviolet. The most important type of DNA repair in human cells is called excision repair. This multistep process removes damaged or inappropriate pieces of DNA -- often as a string of 29 nucleotides containing the damage -- and replaces them with intact ones. We have isolated, cloned, and mapped several human repair genes associated with the nucleotide excision repair pathway and involved in the repair of DNA damage after exposure to ultraviolet light or mutagens in cooked food. We have shown that a defect in one of these repair genes, ERCC2, is responsible for the repair deficiency in one of the groups of patients with the recessive genetic disorder xeroderma pigmentosum (XP group D). We are exploring ways to purify sufficient quantities (milligrams) of the protein products of these and other repair genes so that we can understand their functions. Our long-term goals are to link defective repair proteins to human DNA repair disorders that predispose to cancer, and to produce DNA-repair-deficient mice that can serve as models for the human disorders.

  20. Pantex breaks ground on renewable energy project | National Nuclear...

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

    breaks ground on renewable energy project | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

  1. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    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 but...

  2. Breaking of Symmetry in Graphene Growth on Metal Substrates ...

    Office of Scientific and Technical Information (OSTI)

    Breaking of Symmetry in Graphene Growth on Metal Substrates Not Available Temp HTML Storage 2: Artyukhov, Vasilii I.; Hao, Yufeng; Ruoff, Rodney S.; Yakobson, Boris I. Temp Plain ...

  3. LANL breaks ground on key sediment control project

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

    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...

  4. ESnet's Science DMZ Breaks Down Barriers, Speeds up Science

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

    ESnet's Science DMZ Breaks Down Barriers, Speeds up Science News & Publications ESnet News Media & Press Publications and Presentations Galleries ESnet Awards and Honors Contact Us...

  5. NREL: Solar Research - New Partnerships Help Utilities Break...

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

    New Partnerships Help Utilities Break Down Solar Barriers May 11, 2016 The Solar Technical Assistance Team (STAT) Network launched its first program of technical assistance to ...

  6. Flavor symmetry breaking and vacuum alignment on orbifolds (Journal...

    Office of Scientific and Technical Information (OSTI)

    widely studied for figuring out the masses and mixing angles of standard model fermions. ... MIXING; POTENTIALS; SCALAR FIELDS; STANDARD MODEL; SYMMETRY; SYMMETRY BREAKING; ...

  7. A Gravity Dual of Metastable Dynamical Supersymmetry Breaking...

    Office of Scientific and Technical Information (OSTI)

    Subject: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; DUALITY; EXPECTATION VALUE; RENORMALIZATION; SUPERGRAVITY; SUPERSYMMETRY; SYMMETRY BREAKING; SU GROUPS Theory-HEP,HEPTH...

  8. Breaking the Biological Barriers to Cellulosic Ethanol, June...

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

    ... including optical, X ray, elec- tron, and atomic force; and archives for molecular dynamic simulations of the molecular machinery that breaks down plant cell-wall components. ...

  9. BRCA1 Mutation: A Predictive Marker for Radiation Therapy?

    SciTech Connect (OSTI)

    Kan, Charlene; Zhang, Junran

    2015-10-01

    DNA repair, in particular, DNA double-strand break (DSB) repair, is essential for the survival of both normal and cancer cells. An elaborate repair mechanism has been developed in cells to efficiently repair the damaged DNA. The pathways predominately involved in DSB repair are homologous recombination and classic nonhomologous end-joining, although the alternative NHEJ pathway, a third DSB repair pathway, could also be important in certain contexts. The protein of BRCA1 encoded by the tumor suppressor gene BRCA1 regulates all DSB repair pathways. Given that DSBs represent the most biologically significant lesions induced by ionizing radiation and that impaired DSB repair leads to radiation sensitivity, it has been expected that cancer patients with BRCA1 mutations should benefit from radiation therapy. However, the clinical data have been conflicting and inconclusive. We provide an overview about the current status of the data regarding BRCA1 deficiency and radiation therapy sensitivity in both experimental models and clinical investigations. In addition, we discuss a strategy to potentiate the effects of radiation therapy by poly(ADP-ribose) polymerase inhibitors, the pharmacologic drugs being investigated as monotherapy for the treatment of patients with BRCA1/2 mutations.

  10. Modulated Tool Path Chip Breaking Operation | Y-12 National Security

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

    Complex Modulated Tool Path Chip ... Modulated Tool Path Chip Breaking Operation The mp4 video format is not supported by this browser. Download video Captions: On Time: 2:09 min. The developers of the MTP chip-breaking system, an R&D 100 award winning technology, share some of the system's benefits and uses

  11. The hidden X-ray breaks in afterglow light curves

    SciTech Connect (OSTI)

    Curran, P. A.; Wijers, R. A. M. J.; Horst, A. J. van der; Starling, R. L. C.

    2008-05-22

    Gamma-Ray Burst (GRB) afterglow observations in the Swift era have a perceived lack of achromatic jet breaks compared to the BeppoSAX, or pre-Swift era. Specifically, relatively few breaks, consistent with jet breaks, are observed in the X-ray light curves of these bursts. If these breaks are truly missing, it has serious consequences for the interpretation of GRB jet collimation and energy requirements, and the use of GRBs as standard candles.Here we address the issue of X-ray breaks which are possibly 'hidden' and hence the light curves are misinterpreted as being single power-laws. We show how a number of precedents, including GRB 990510 and GRB 060206, exist for such hidden breaks and how, even with the well sampled light curves of the Swift era, these breaks may be left misidentified. We do so by synthesising X-ray light curves and finding general trends via Monte Carlo analysis. Furthermore, in light of these simulations, we discuss how to best identify achromatic breaks in afterglow light curves via multi-wavelength analysis.

  12. Alkylation damage repair in mammalian genomes

    SciTech Connect (OSTI)

    Mitra, S.; Roy, R.; Kim, N.K. |; Tano, K. |; Ibeanu, G.C. |; Dunn, W.C.; Natarajan, A.T.; Hartenstein, B.; Kaina, B.

    1992-11-01

    The repair of O{sup 6} -alkylguanine in DNA involves only O{sup 6} -methyltransferase (MGMT) while the repair of N-alkylpurines requires multiple proteins including N-methylpurine-DNA glycosylase (MPG). While the biochemical properties human and mouse MGMTs are very similar, the mouse MPG removes 7-methylguanine more efficiently than the human protein. An increased level of MGMT, without a change in the level of MPG associated with gene amplification, was observed in a mouse cell line resistant to 2-chloroethyl-N-nitrosourea. In contrast, no correlation was observed between MPG level and resistance to methyl methanesulfonate in Chinese hamster ovary (CHO) cells. This result suggests a protein other than MPG limits the repair rate of N-alkylpurine in CHO cells.

  13. Alkylation damage repair in mammalian genomes

    SciTech Connect (OSTI)

    Mitra, S.; Roy, R.; Kim, N.K. . Sealy Center for Molecular Science Oak Ridge National Lab., TN ); Tano, K. Oak Ridge National Lab., TN ); Ibeanu, G.C. Oak Ridge National Lab., TN ); Dunn, W.C. (

    1992-01-01

    The repair of O{sup 6} -alkylguanine in DNA involves only O{sup 6} -methyltransferase (MGMT) while the repair of N-alkylpurines requires multiple proteins including N-methylpurine-DNA glycosylase (MPG). While the biochemical properties human and mouse MGMTs are very similar, the mouse MPG removes 7-methylguanine more efficiently than the human protein. An increased level of MGMT, without a change in the level of MPG associated with gene amplification, was observed in a mouse cell line resistant to 2-chloroethyl-N-nitrosourea. In contrast, no correlation was observed between MPG level and resistance to methyl methanesulfonate in Chinese hamster ovary (CHO) cells. This result suggests a protein other than MPG limits the repair rate of N-alkylpurine in CHO cells.

  14. Repairable chip bonding/interconnect process

    DOE Patents [OSTI]

    Bernhardt, A.F.; Contolini, R.J.; Malba, V.; Riddle, R.A.

    1997-08-05

    A repairable, chip-to-board interconnect process which addresses cost and testability issues in the multi-chip modules is disclosed. This process can be carried out using a chip-on-sacrificial-substrate technique, involving laser processing. This process avoids the curing/solvent evolution problems encountered in prior approaches, as well is resolving prior plating problems and the requirements for fillets. For repairable high speed chip-to-board connection, transmission lines can be formed on the sides of the chip from chip bond pads, ending in a gull wing at the bottom of the chip for subsequent solder. 10 figs.

  15. Repairable chip bonding/interconnect process

    DOE Patents [OSTI]

    Bernhardt, Anthony F.; Contolini, Robert J.; Malba, Vincent; Riddle, Robert A.

    1997-01-01

    A repairable, chip-to-board interconnect process which addresses cost and testability issues in the multi-chip modules. This process can be carried out using a chip-on-sacrificial-substrate technique, involving laser processing. This process avoids the curing/solvent evolution problems encountered in prior approaches, as well is resolving prior plating problems and the requirements for fillets. For repairable high speed chip-to-board connection, transmission lines can be formed on the sides of the chip from chip bond pads, ending in a gull wing at the bottom of the chip for subsequent solder.

  16. Protein Bridges DNA Base and Nucleotide Excision Repair Pathways

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

    ... It turns out that ATL bridges two DNA repair pathways (base repair and nucleotide excision ... By mapping conservation of amino acid sequences between their ATL and sequences in other ...

  17. Solar Water Heating System Maintenance and Repair | Department...

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

    Water Heating System Maintenance and Repair Solar Water Heating System Maintenance and Repair May 30, 2012 - 2:35pm Addthis Rooftop solar water heaters need regular maintenance to...

  18. Antibody specific for a DNA repair protein

    DOE Patents [OSTI]

    Petrini, John H.; Morgan, William Francis; Maser, Richard Scott; Carney, James Patrick

    2006-07-11

    An isolated and purified DNA molecule encoding a DNA repair protein, p95, is provided, as is isolated and purified p95. Also provided are methods of detecting p95 and DNA encoding p95. The invention further provides p95 knock-out mice.

  19. DNA encoding a DNA repair protein

    DOE Patents [OSTI]

    Petrini, John H.; Morgan, William Francis; Maser, Richard Scott; Carney, James Patrick

    2006-08-15

    An isolated and purified DNA molecule encoding a DNA repair protein, p95, is provided, as is isolated and purified p95. Also provided are methods of detecting p95 and DNA encoding p95. The invention further provides p95 knock-out mice.

  20. Selected Bibliography on Electric Motor Repair

    Office of Energy Efficiency and Renewable Energy (EERE)

    The following series of repair documents related to electric motors were produced by the U.S. Department of Energy's Advanced Manufacturing Office (formerly the Office of Industrial Technologies) with input from trade associations, consulting companies, manufacturers, non-profit operations, and others.

  1. Inspect and Repair Steam Traps | Department of Energy

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

    Inspect and Repair Steam Traps Inspect and Repair Steam Traps This tip sheet on inspecting and repairing steam traps provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies. STEAM TIP SHEET #1 Inspect and Repair Steam Traps (January 2012) (393.77 KB) More Documents & Publications Flash High-Pressure Condensate to Regenerate Low-Pressure Steam Steam Pressure Reduction: Opportunities and Issues Use Steam Jet Ejectors or Thermocompressors

  2. Component Repair Times Obtained from MSPI Data

    SciTech Connect (OSTI)

    Eide, Steven A.

    2015-05-01

    Information concerning times to repair or restore equipment to service given a failure is valuable to probabilistic risk assessments (PRAs). Examples of such uses in modern PRAs include estimation of the probability of failing to restore a failed component within a specified time period (typically tied to recovering a mitigating system before core damage occurs at nuclear power plants) and the determination of mission times for support system initiating event (SSIE) fault tree models. Information on equipment repair or restoration times applicable to PRA modeling is limited and dated for U.S. commercial nuclear power plants. However, the Mitigating Systems Performance Index (MSPI) program covering all U.S. commercial nuclear power plants provides up-to-date information on restoration times for a limited set of component types. This paper describes the MSPI program data available and analyzes the data to obtain median and mean component restoration times as well as non-restoration cumulative probability curves. The MSPI program provides guidance for monitoring both planned and unplanned outages of trains of selected mitigating systems deemed important to safety. For systems included within the MSPI program, plants monitor both train UA and component unreliability (UR) against baseline values. If the combined system UA and UR increases sufficiently above established baseline results (converted to an estimated change in core damage frequency or CDF), a “white” (or worse) indicator is generated for that system. That in turn results in increased oversight by the US Nuclear Regulatory Commission (NRC) and can impact a plant’s insurance rating. Therefore, there is pressure to return MSPI program components to service as soon as possible after a failure occurs. Three sets of unplanned outages might be used to determine the component repair durations desired in this article: all unplanned outages for the train type that includes the component of interest, only

  3. Emergency pipe line repair connects subsea pipe lines

    SciTech Connect (OSTI)

    Lerique, M.P.; Thiberge, P. ); Wright, N. )

    1990-11-01

    Emergency repair of any subsea line pipe must form a high-integrity, metal-to-metal seal. This paper presents a remote, diverless repair system that utilizes master flanges, a connector and a spool piece to repair line pipe in deep offshore waters.

  4. How Things Break (And Why Scientists Want to Know) | Argonne...

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

    This article was published in the spring 2016 issue of Argonne Now, the laboratory science magazine. Click for the rest of the issue. How Things Break (And Why Scientists Want to ...

  5. A Gravity Dual of Metastable Dynamical Supersymmetry Breaking...

    Office of Scientific and Technical Information (OSTI)

    US0801780 DOE Contract Number: AC02-76SF00515 Resource ... Language: English Subject: 72 PHYSICS OF ELEMENTARY ... BREAKING; SU GROUPS Theory-HEP,HEPTH Word Cloud More ...

  6. Symmetry-Breaking Orbital Anisotropy Observed for Detwinned Ba...

    Office of Scientific and Technical Information (OSTI)

    Symmetry-Breaking Orbital Anisotropy Observed for Detwinned Ba(Fe (1-X) Co (X) ) (2) As (2) Above the Spin Density Wave Transition Citation Details In-Document Search Title: ...

  7. Break-out Discussion i: Modeling Consumer Behavior Residential Scale |

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

    Department of Energy Break-out Discussion i: Modeling Consumer Behavior Residential Scale Break-out Discussion i: Modeling Consumer Behavior Residential Scale This presentaion summarizes the information discussed during the breakout session on modeling consumer behavior during the DOE Ad Lucem Workshop on Feb. 17, 2012. adlucem2012_behavior_breakout.pdf (589.64 KB) More Documents & Publications Ad Lucem: Modeling of Market Transformation Pathways Workshop Agenda Modeling Solar Energy

  8. Deputy Secretary Poneman Attends Ground Breaking at Tennessee Advanced

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

    Vehicle Battery Plant | Department of Energy 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

  9. Regional Test Centers Breaking Down Barriers to Solar Energy Deployment |

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

    Department of Energy Regional Test Centers Breaking Down Barriers to Solar Energy Deployment Regional Test Centers Breaking Down Barriers to Solar Energy Deployment September 3, 2014 - 6:16pm Addthis EERE Assistant Secretary Dr. David Danielson stands with Senator Bernie Sanders of Vermont at the state's new regional solar test center. | Photo credit Kevin Fitzmaurice, Energy Department. EERE Assistant Secretary Dr. David Danielson stands with Senator Bernie Sanders of Vermont at the state's

  10. Energy Department Training Breaks New Ground | Department of Energy

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

    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 Timothy Unruh FEMP Director High quality education for federal government employees helps streamline operations, improve services, and ensure that taxpayer dollars are

  11. EERE Success Story-Indiana Manufacturing Institute Breaks Ground at

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

    Purdue University in support of Composites Manufacturing Research | Department of Energy Indiana Manufacturing Institute Breaks Ground at Purdue University in support of Composites Manufacturing Research EERE Success Story-Indiana Manufacturing Institute Breaks Ground at Purdue University in support of Composites Manufacturing Research July 14, 2015 - 1:16pm Addthis Left: Gary Bertoline, Dean of Purdue Polytechnic Institute; Kelly Visconti, Technology Manager for the U.S. Department of

  12. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    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

  13. More than $3 million raised during record-breaking Employee Giving...

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

    Record-breaking employee giving campaign Community Connections: Your link to news and ... More than 3 million raised during record-breaking Employee Giving Campaign Contributions ...

  14. The Honorable Deborah L. Wince-Smith Discusses Breaking the Glass...

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

    The Honorable Deborah L. Wince-Smith Discusses Breaking the Glass Ceiling in Manufacturing The Honorable Deborah L. Wince-Smith Discusses Breaking the Glass Ceiling in ...

  15. Helium bubble distributions in reactor tank repair specimens. Part 1

    SciTech Connect (OSTI)

    Tosten, M.H.; Kestin, P.A.

    1992-03-01

    This report discusses the Reactor Tank Repair (RTR) program was initiated to develop an in-tank repair process capable of repairing stress corrosion cracks within the SRS reactor tank walls, in the event that such a repair is needed. Previous attempts to repair C-reactor tank with a gas tungsten arc (GTA) welding process were unsuccessful due to significant cracking that occurred in the heat-affected-zones adjacent to the repair welds. It was determined that this additional cracking was a result of helium embrittlement caused by the combined effects of helium (existing within the tank walls), the high heat input associated with the GTA process, and weld shrinkage stresses. Based on the results of earlier studies it was suggested that the effects of helium embrittlement could be minimized by using a low heat input GMA process. Metallographic analysis played an important role throughout the investigation of alternative welding methods for the repair of helium-containing materials.

  16. Helium bubble distributions in reactor tank repair specimens

    SciTech Connect (OSTI)

    Tosten, M.H.; Kestin, P.A.

    1992-03-01

    This report discusses the Reactor Tank Repair (RTR) program was initiated to develop an in-tank repair process capable of repairing stress corrosion cracks within the SRS reactor tank walls, in the event that such a repair is needed. Previous attempts to repair C-reactor tank with a gas tungsten arc (GTA) welding process were unsuccessful due to significant cracking that occurred in the heat-affected-zones adjacent to the repair welds. It was determined that this additional cracking was a result of helium embrittlement caused by the combined effects of helium (existing within the tank walls), the high heat input associated with the GTA process, and weld shrinkage stresses. Based on the results of earlier studies it was suggested that the effects of helium embrittlement could be minimized by using a low heat input GMA process. Metallographic analysis played an important role throughout the investigation of alternative welding methods for the repair of helium-containing materials.

  17. Effects of solar ultraviolet photons on mammalian cell DNA. [UVA (320-400 nm):a2

    SciTech Connect (OSTI)

    Peak, M.J.; Peak, J.G.

    1991-01-01

    This document presents information on the possible mechanisms of carcinogenesis caused by UVA (ultraviolet radiation in the 320--400 nm region). Most studies showing the carcinogenic effects of ultraviolet light have concentrated on UVB (280--320 nm). UVA had been considered harmless even though it penetrates biological tissues better than UVB. Recently, it has become apparent that UVA is also capable of causing damage to cellular DNA. This was unexpected because the DNA UV absorption spectrum indicates a negligible probability that photons of wavelengths longer than 320 nm will be directly absorbed. The most common defects induced in DNA by UVB are pyrimidine photoproducts, such as thymidine dimers. UVA photons produce defects resembling those caused by ionizing radiations: single- and double-strand breaks, and DNA-protein crosslinks. This paper also discusses the role of DNA repair mechanisms in UVA-induced defects and the molecular mechanisms of UVA damage induction. 38 refs. (MHB)

  18. Nonenzymatic Role for WRN in Preserving Nascent DNA Strands after Replication Stress

    SciTech Connect (OSTI)

    Su, Fengtao; Mukherjee, Shibani; Yang, Yanyong; Mori, Eiichiro; Bhattacharya, Souparno; Kobayashi, Junya; Yannone, Steven  M.; Chen, David  J.; Asaithamby, Aroumougame

    2014-11-20

    WRN, the protein defective in Werner syndrome (WS), is a multifunctional nuclease involved in DNA damage repair, replication, and genome stability maintenance. It was assumed that the nuclease activities of WRN were critical for these functions. Here, we report a nonenzymatic role for WRN in preserving nascent DNA strands following replication stress. We found that lack of WRN led to shortening of nascent DNA strands after replication stress. Furthermore, we discovered that the exonuclease activity of MRE11 was responsible for the shortening of newly replicated DNA in the absence of WRN. Mechanistically, the N-terminal FHA domain of NBS1 recruits WRN to replication-associated DNA double-stranded breaks to stabilize Rad51 and to limit the nuclease activity of its C-terminal binding partner MRE11. Thus, this previously unrecognized nonenzymatic function of WRN in the stabilization of nascent DNA strands sheds light on the molecular reason for the origin of genome instability in WS individuals.

  19. Strong Electroweak Symmetry Breaking and Spin-0 Resonances

    SciTech Connect (OSTI)

    Evans, Jared; Luty, Markus A.

    2009-09-04

    We argue that theories of the strong electroweak symmetry breaking sector necessarily contain new spin 0 states at the TeV scale in the tt and tb/bt channels, even if the third generation quarks are not composite at the TeV scale. These states couple sufficiently strongly to third generation quarks to have significant production at LHC via gg->phi{sup 0} or gb->tphi{sup -}. The existence of narrow resonances in QCD suggests that the strong electroweak breaking sector contains narrow resonances that decay to tt or tb/bt, with potentially significant branching fractions to 3 or more longitudinal W and Z bosons. These may give new 'smoking gun' signals of strong electroweak symmetry breaking.

  20. Application of break preclusion concept in German nuclear power plants

    SciTech Connect (OSTI)

    Roos, E.; Maier, V.; Nagel, G.

    1997-04-01

    The break preclusion concept is based on {open_quotes}KTA rules{close_quotes}, {open_quotes}RSK guidelines{close_quotes} and {open_quotes}Rahmenspeziflkation Basissicherheit{close_quotes}. These fundamental rules containing for example requirements on material, design, calculation, manufacturing and testing procedures are explained and the technical realisation is shown by means of examples. The proof of the quality of these piping systems can be executed by means of fracture mechanics calculations by showing that in every case the leakage monitoring system already detect cracks which are clearly smaller than the critical crack. Thus the leak before break behavior and the break preclusion concept is implicitly affirmed. In order to further diminish conservativities in the fracture mechanics procedures, specific research projects are executed which are explained in this contribution.

  1. SB Electronics Breaks Ground on New Factory | Department of Energy

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

    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 Paul Lester Digital Content Specialist, Office of Public Affairs A Vermont company broke ground on a new

  2. Jefferson Lab Breaks Ground On $310 Million Project | Jefferson Lab

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

    Breaks Ground On $310 Million Project Jefferson Lab Breaks Ground On $310 Million Project groundbreaking Newport News Mayor Joe Frank addresses the crowd at the groundbreaking ceremony for the Jefferson Lab 12 GeV Upgrade. Also on the stage are (front row, l-r) U.S. Rep. Rob Wittman of Virginia's 1st District; U.S. Rep. Bobby Scott of Virginia's 3rd District; Gene Henry, Associate Director of the DOE's Office of Science for Nuclear Physics; Jefferson Lab Director Hugh Montgomery; (back row, l-r)

  3. Margins in high temperature leak-before-break assessments

    SciTech Connect (OSTI)

    Budden, P.J.; Hooton, D.G.

    1997-04-01

    Developments in the defect assessment procedure R6 to include high-temperature mechanisms in Leak-before-Break arguments are described. In particular, the effect of creep on the time available to detect a leak and on the crack opening area, and hence leak rate, is discussed. The competing influence of these two effects is emphasized by an example. The application to Leak-before-Break of the time-dependent failure assessment diagram approach for high temperature defect assessment is then outlined. The approach is shown to be of use in assessing the erosion of margins by creep.

  4. Restore: Modeling Repair and Restoration Processes | Argonne National

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

    Laboratory Restore: Modeling Repair and Restoration Processes Restore: Modeling Repair and Restoration Processes Argonne's Restore software models complex sets of steps required to accomplish a goal, such as repairing a ruptured natural gas pipeline, when the time required to complete a step may be uncertain. For example, external conditions (i.e., the time of day, weather, and availability of crew) may affect one or more of the steps required to accomplish a goal. Therefore,

  5. Occupational Radiation Exposure During Endovascular Aortic Repair

    SciTech Connect (OSTI)

    Sailer, Anna M.; Schurink, Geert Willem H.; Bol, Martine E. Haan, Michiel W. de Zwam, Willem H. van Wildberger, Joachim E. Jeukens, Cécile R. L. P. N.

    2015-08-15

    PurposeThe aim of the study was to evaluate the radiation exposure to operating room personnel and to assess determinants for high personal doses during endovascular aortic repair.Materials and MethodsOccupational radiation exposure was prospectively evaluated during 22 infra-renal aortic repair procedures (EVAR), 11 thoracic aortic repair procedures (TEVAR), and 11 fenestrated or branched aortic repair procedures (FEVAR). Real-time over-lead dosimeters attached to the left breast pocket measured personal doses for the first operators (FO) and second operators (SO), radiology technicians (RT), scrub nurses (SN), anesthesiologists (AN), and non-sterile nurses (NSN). Besides protective apron and thyroid collar, no additional radiation shielding was used. Procedural dose area product (DAP), iodinated contrast volume, fluoroscopy time, patient’s body weight, and C-arm angulation were documented.ResultsAverage procedural FO dose was significantly higher during FEVAR (0.34 ± 0.28 mSv) compared to EVAR (0.11 ± 0.21 mSv) and TEVAR (0.06 ± 0.05 mSv; p = 0.003). Average personnel doses were 0.17 ± 0.21 mSv (FO), 0.042 ± 0.045 mSv (SO), 0.019 ± 0.042 mSv (RT), 0.017 ± 0.031 mSv (SN), 0.006 ± 0.007 mSv (AN), and 0.004 ± 0.009 mSv (NSN). SO and AN doses were strongly correlated with FO dose (p = 0.003 and p < 0.001). There was a significant correlation between FO dose and procedural DAP (R = 0.69, p < 0.001), iodinated contrast volume (R = 0.67, p < 0.001) and left-anterior C-arm projections >60° (p = 0.02), and a weak correlation with fluoroscopy time (R = 0.40, p = 0.049).ConclusionAverage FO dose was a factor four higher than SO dose. Predictors for high personal doses are procedural DAP, iodinated contrast volume, and left-anterior C-arm projections greater than 60°.

  6. Federal Facilities Maintenance, Repair Report Calls for Action

    SciTech Connect (OSTI)

    Bartlett, Rosemarie

    2012-10-01

    This article is an overview of a recent report by the Federal Facilities Council on "Predicting Outcomes from Investments in Maintenance and Repair of Federal Facilities."

  7. Leveraging Service Calls and Emergency Repairs for Energy Efficiency Marketing

    Broader source: Energy.gov [DOE]

    Better Buildings Residential Network Peer Exchange Call Series: Leveraging Service Calls and Emergency Repairs, Call Slides and Discussion Summary, November 13, 2014.

  8. Window Replacement, Rehabilitation, & Repair Guides- Building America Top Innovation

    Broader source: Energy.gov [DOE]

    Building America team Building Science Corporation guides contractors through several options for repairing or replacing old windows to improve air sealing and thermal performance.

  9. Advanced maintenance, inspection & repair technology for nuclear power plants

    SciTech Connect (OSTI)

    Hinton, B.M.

    1994-12-31

    Maintenance, inspection, and repair technology for nuclear power plants is outlined. The following topics are discussed: technology for reactor systems, reactor refueling bridge, fuel inspection system, fuel shuffling software, fuel reconstitution, CEA/RCCA/CRA inspection, vessel inspection capabilities, CRDM inspection and repair, reactor internals inspection and repair, stud tensioning system, stud/nut cleaning system, EDM machining technology, MI Cable systems, core exit T/C nozzle assemblies, technology for steam generators, genesis manipulator systems, ECT, UT penetrant inspections, steam generator repair and cleaning systems, technology for balance of plant, heat exchangers, piping and weld inspections, and turbogenerators.

  10. Towards breaking temperature equilibrium in multi-component Eulerian schemes

    SciTech Connect (OSTI)

    Grove, John W; Masser, Thomas

    2009-01-01

    We investigate the effects ofthermal equilibrium on hydrodynamic flows and describe models for breaking the assumption ofa single temperature for a mixture of components in a cell. A computational study comparing pressure-temperature equilibrium simulations of two dimensional implosions with explicit front tracking is described as well as implementation and J-D calculations for non-equilibrium temperature methods.

  11. How does a thermal binary crystal break under shear?

    SciTech Connect (OSTI)

    Horn, Tobias Löwen, Hartmut

    2014-12-14

    When exposed to strong shearing, the particles in a crystal will rearrange and ultimately, the crystal will break by forming large nonaffine defects. Even for the initial stage of this process, only little effort has been devoted to the understanding of the breaking process on the scale of the individual particle size for thermalized mixed crystals. Here, we explore the shear-induced breaking for an equimolar two-dimensional binary model crystal with a high interaction asymmetry between the two different species such that the initial crystal has an intersecting square sublattice of the two constituents. Using Brownian dynamics computer simulations, we show that the combination of shear and thermal fluctuations leads to a characteristic hierarchical breaking scenario where initially, the more strongly coupled particles are thermally distorted, paving the way for the weakly coupled particles to escape from their cage. This in turn leads to mobile defects which may finally merge, proliferating a cascade of defects, which triggers the final breakage of the crystal. This scenario is in marked contrast to the breakage of one-component crystals close to melting. Moreover, we explore the orientational dependence of the initial shear direction relative to the crystal orientation and compare this to the usual melting scenario without shear. Our results are verifiable in real-space experiments of superparamagnetic colloidal mixtures at a pending air-water interface in an external magnetic field where the shear can be induced by an external laser field.

  12. EECBG Success Story: Breaking Ground in Miami-Dade

    Broader source: Energy.gov [DOE]

    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. Learn more.

  13. Waste minimization in an autobody repair shop

    SciTech Connect (OSTI)

    Baria, D.N.; Dorland, D.; Bergeron, J.T.

    1994-12-31

    This work was done to document the waste minimization incorporated in a new autobody repair facility in Hermantown, Minnesota. Humes Collision Center incorporated new waste reduction techniques when it expanded its old facilities in 1992 and it was able to achieve the benefits of cost reduction and waste reduction. Humes Collision Center repairs an average of 500 cars annually and is a very small quantity generator (VSQG) of hazardous waste, as defined by the Minnesota Pollution Control Agency (MPCA). The hazardous waste consists of antifreeze, batteries, paint sludge, refrigerants, and used oil, while the nonhazardous waste consists of cardboard, glass, paint filters, plastic, sanding dust, scrap metal, and wastewater. The hazardous and nonhazardous waste output were decreased by 72%. In addition, there was a 63% reduction in the operating costs. The waste minimization includes antifreeze recovery and recycling, reduction in unused waste paint, reduction, recovery and recycle of waste lacquer thinner for cleaning spray guns and paint cups, elimination of used plastic car bags, recovery and recycle of refrigerant, reduction in waste sandpaper and elimination of sanding dust, and elimination of waste paint filters. The rate of return on the investment in waste minimization equipment is estimated from 37% per year for the distillation unit, 80% for vacuum sanding, 146% for computerized paint mixing, 211% for the refrigerant recycler, to 588% per year for the gun washer. The corresponding payback time varies from 3 years to 2 months.

  14. Gedanken Worlds without Higgs: QCD-Induced Electroweak Symmetry Breaking

    SciTech Connect (OSTI)

    Quigg, Chris; Shrock, Robert; /YITP, Stony Brook

    2009-01-01

    To illuminate how electroweak symmetry breaking shapes the physical world, we investigate toy models in which no Higgs fields or other constructs are introduced to induce spontaneous symmetry breaking. Two models incorporate the standard SU(3){sub c} {circle_times} SU(2){sub L} {circle_times} U(1){sub Y} gauge symmetry and fermion content similar to that of the standard model. The first class--like the standard electroweak theory--contains no bare mass terms, so the spontaneous breaking of chiral symmetry within quantum chromodynamics is the only source of electroweak symmetry breaking. The second class adds bare fermion masses sufficiently small that QCD remains the dominant source of electroweak symmetry breaking and the model can serve as a well-behaved low-energy effective field theory to energies somewhat above the hadronic scale. A third class of models is based on the left-right-symmetric SU(3){sub c} {circle_times} SU(2){sub L} {circle_times} SU(2){sub R} {circle_times} U(1)B?L gauge group. In a fourth class of models, built on SU(4){sub PS} {circle_times} SU(2){sub L} {circle_times} SU(2){sub R} gauge symmetry, lepton number is treated as a fourth color. Many interesting characteristics of the models stem from the fact that the effective strength of the weak interactions is much closer to that of the residual strong interactions than in the real world. The Higgs-free models not only provide informative contrasts to the real world, but also lead us to consider intriguing issues in the application of field theory to the real world.

  15. Deep patch technique for landslide repair. Final report

    SciTech Connect (OSTI)

    Helwany, B.M.

    1994-10-01

    The report describes the laboratory testing of the `USFS deep patch` technique and a CTI modification of this technique for repairing landslides with geosynthetic reinforcement. The technique involves replacing sections of roadway lost due to landslides on top of a geosynthetically-reinforced embankment. The CTI modification involves replacing the reinforced slope with a geosynthetically-reinforced retaining wall with a truncated base. Both techniques rely on the cantilevering ability of the reinforced mass to limit the load on the foundation with a high slide potential. The tests with road base showed that (1) both the USFS and CTI repair reduced effectively the adverse effects of local landsliding on the highway pavement by preventing crack propagation; (2) the USFS repair increased the stability of the repaired slope, which was in progressive failure, by reducing the stresses exerted on it; and (3) the CTI repair produced substantially greater stresses on its foundation due to the truncated base of the reinforced mass.

  16. Traveling solitons in Lorentz and CPT breaking systems

    SciTech Connect (OSTI)

    Souza Dutra, A. de; Correa, R. A. C.

    2011-05-15

    In this work we present a class of traveling solitons in Lorentz and CPT breaking systems. In the case of Lorentz violating scenarios, as far as we know, only static solitonic configurations were analyzed up to now in the literature. Here it is shown that it is possible to construct some traveling solitons which cannot be mapped into static configurations by means of Lorentz boosts due to explicit breaking. In fact, the traveling solutions cannot be reached from the static ones by using something similar to a Lorentz boost in those cases. Furthermore, in the model studied, a complete set of exact solutions is obtained. The solutions present a critical behavior controlled by the choice of an arbitrary integration constant.

  17. Single-Sector Supersymmetry Breaking, Chirality, and Unification

    SciTech Connect (OSTI)

    Behbahani, Siavosh R.; Craig, Nathaniel; Torroba, Gonzalo; /SLAC /Stanford U., Phys. Dept.

    2011-08-12

    Calculable single-sector models provide an elegant framework for generating the flavor textures via compositeness, breaking supersymmetry, and explaining the electroweak scale. Such models may be realized naturally in supersymmetric QCD with additional gauge singlets (SSQCD), though it remains challenging to construct models without a surfeit of light exotic states where the Standard Model index emerges naturally. We classify possible single-sector models based on Sp confining SSQCD according to their Standard Model index and number of composite messengers. This leads to simple, calculable models that spontaneously break supersymmetry, reproduce the fermion flavor hierarchy, and explain the Standard Model index dynamically with little or no additional matter. At low energies these theories realize a 'more minimal' soft spectrum with direct mediation and a gravitino LSP.

  18. Breaking discrete symmetries in the effective field theory of inflation

    SciTech Connect (OSTI)

    Cannone, Dario; Gong, Jinn-Ouk; Tasinato, Gianmassimo

    2015-08-03

    We study the phenomenon of discrete symmetry breaking during the inflationary epoch, using a model-independent approach based on the effective field theory of inflation. We work in a context where both time reparameterization symmetry and spatial diffeomorphism invariance can be broken during inflation. We determine the leading derivative operators in the quadratic action for fluctuations that break parity and time-reversal. Within suitable approximations, we study their consequences for the dynamics of linearized fluctuations. Both in the scalar and tensor sectors, we show that such operators can lead to new direction-dependent phases for the modes involved. They do not affect the power spectra, but can have consequences for higher correlation functions. Moreover, a small quadrupole contribution to the sound speed can be generated.

  19. Women in STEM careers: Breaking down barriers | Argonne National Laboratory

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

    This article was published in the spring 2016 issue of Argonne Now, the laboratory science magazine. Click for the rest of the issue. Women in STEM careers: Breaking down barriers By Diana Anderson * March 7, 2016 Tweet EmailPrint This article was originally published in the spring 2016 issue of Argonne Now, the laboratory's science magazine. Growing national attention is focused on increasing the number of women in Science, Technology, Engineering, and Mathematics (STEM) careers. Even as

  20. Break-out Discussion i: Modeling Consumer Behavior Residential Scale

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

    Break-out Discussion I: Modeling Consumer Behavior Residential Scale  Are we asking the right questions?  What is a question we could ask about modeling consumer behavior that might lead to deeper insights into how to spur innovation? Why Are We Here? 2 Opower: visual comparison 3 opower 4 EERE Home Energy Score 5 * Similar comparison model * Adds climate context * Simple, visual  Data: - How much - What type  Data: - What is actionable today? - What is bodacious, over-the-top

  1. Symmetry-breaking instability of quadratic soliton bound states

    SciTech Connect (OSTI)

    Delque, Michaeel; Fanjoux, Gil; Maillotte, Herve; Kockaert, Pascal; Sylvestre, Thibaut; Haelterman, Marc

    2011-01-15

    We study both numerically and experimentally two-dimensional soliton bound states in quadratic media and demonstrate their symmetry-breaking instability. The experiment is performed in a potassium titanyl phosphate crystal in a type-II configuration. The bound state is generated by the copropagation of the antisymmetric fundamental beam locked in phase with the symmetrical second harmonic one. Experimental results are in good agreement with numerical simulations of the nonlinear wave equations.

  2. LANL breaks ground on key sediment control project

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

    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

  3. New Partnerships Help Utilities Break Down Solar Barriers | Energy Systems

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

    Integration | NREL New Partnerships Help Utilities Break Down Solar Barriers May 11, 2016 The Solar Technical Assistance Team (STAT) Network launched its first program of technical assistance to electric utilities and announced three new efforts to provide direct support to utility partners. The activities range from providing interconnection training to conducting detailed techno-economic modeling to leveraging community solar finance tools. The National Renewable Energy Laboratory (NREL),

  4. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    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

  5. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    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

  6. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    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

  7. Symmetry Breaking of H2 Dissociation by a Single Photon

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

    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

  8. Sandia California breaks ground on new building | National Nuclear Security

    National Nuclear Security Administration (NNSA)

    Administration | (NNSA) breaks ground on new building Monday, August 3, 2015 - 11:11am A groundbreaking ceremony was recently held in Livermore, Calif., for a building that will enable consolidation of "front door" activities for Sandia National Laboratories California. NNSA Blog Building 926 will house the site's human resources department and will be home of the training center for students and new hires. The new 20,000 square foot facility, funded by institutional investments,

  9. U.S. Department of Energy Breaks Ground on State-of-the-Art Wind...

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

    Breaks Ground on State-of-the-Art Wind Turbine Test Facility U.S. Department of Energy Breaks Ground on State-of-the-Art Wind Turbine Test Facility October 1, 2012 - 12:08pm ...

  10. Soft supersymmetry breaking terms from D{sub 4}xZ{sub 2} lepton...

    Office of Scientific and Technical Information (OSTI)

    Soft supersymmetry breaking terms from Dsub 4xZsub 2 lepton flavor symmetry Citation Details In-Document Search Title: Soft supersymmetry breaking terms from Dsub 4xZsub 2 ...

  11. Fatigue response of repaired thick aluminum panels with bondline flaws

    SciTech Connect (OSTI)

    Conley, D.S.

    1999-03-01

    This research investigated the fatigue response of precracked 558 x 177.8 x 6.35 mm (22.0 x 7.0 x 0.25 in) 2024-T351 aluminum panels repaired with single-sided partially bonded, unidirectional, eighteen ply boron/epoxy reinforcements. Disbonds were introduced into the bondline of each repair during the adhesion process using teflon inserts. Five different disbond configurations, with varying disbond locations and sizes, were tested. Each repaired panel was subjected to constant amplitude cyclic fatigue loading with a maximum stress of 120MPa. Results from the different configurations were compared against one another and against repaired panels with no debonds to assess the effect of disbonds on repair life. Results from the experimentation showed that even in the case of very large disbonds (20% of total bond area), the bonded repairs significantly extended the lives of the cracked panels. Disbond configurations with disbonds located away from the crack in the aluminum panel, performed comparably to the repaired panel with no disbonds. Disbond configurations with disbonds covering the crack in the aluminum panel yielded slightly lower lives than those obtained from repaired panels with no disbonds. Cyclic fatigue loading caused no increase in size of the artificially induced disbonds. Cyclic disbond growth was observed in the immediate vicinity of the crack. Finite element analysis using the Three Layer Technique was performed to assess the ability of current modeling techniques in predicting the life of cracked thick aluminum panels repaired with composite patches. Results from the finite element analysis were shown to very closely match experimental data.

  12. Insulin-Like Growth Factor-Type 1 Receptor Inhibitor NVP-AEW541 Enhances Radiosensitivity of PTEN Wild-Type but Not PTEN-Deficient Human Prostate Cancer Cells

    SciTech Connect (OSTI)

    Isebaert, Sofie F.; Swinnen, Johannes V.; McBride, William H.; Haustermans, Karin M.

    2011-09-01

    Purpose: During the past decade, many clinical trials with both monoclonal antibodies and small molecules that target the insulin-like growth factor-type 1 receptor (IGF-1R) have been launched. Despite the important role of IGF-1R signaling in radioresistance, studies of such agents in combination with radiotherapy are lagging behind. Therefore, the aim of this study was to investigate the effect of the small molecule IGF-1R kinase inhibitor NVP-AEW541 on the intrinsic radioresistance of prostate cancer cells. Methods and Materials: The effect of NVP-AEW541 on cell proliferation, cell viability, IGF-1R signaling, radiosensitivity, cell cycle distribution, and double strand break repair was determined in three human prostate cancer cell lines (PC3, DU145, 22Rv1). Moreover, the importance of the PTEN pathway status was explored by means of transfection experiments with constitutively active Akt or inactive kinase-dead Akt. Results: NVP-AEW541 inhibited cell proliferation and decreased cell viability in a time-and dose-dependent manner in all three cell lines. Radiosensitization was observed in the PTEN wild-type cell lines DU145 and 22Rv1 but not in the PTEN-deficient PC3 cell line. NVP-AEW541-induced radiosensitization coincided with downregulation of phospho-Akt levels and high levels of residual double strand breaks. The importance of PTEN status in the radiosensitization effect was confirmed by transfection experiments with constitutively active Akt or inactive kinase-dead Akt. Conclusions: NVP-AEW541 enhances the effect of ionizing radiation in PTEN wild-type, but not in PTEN-deficient, prostate cancer cells. Proper patient selection based on the PTEN status of the tumor will be critical to the achievement of optimal results in clinical trials in which the combination of radiotherapy and this IGF-1R inhibitor is being explored.

  13. Modulation of DNA repair capacity and mRNA expression levels of XRCC1, hOGG1 and XPC genes in styrene-exposed workers

    SciTech Connect (OSTI)

    Hanova, Monika; Stetina, Rudolf; Vodickova, Ludmila; Vaclavikova, Radka; Hlavac, Pavel; Smerhovsky, Zdenek; Naccarati, Alessio; Polakova, Veronika; Soucek, Pavel; Kuricova, Miroslava; Manini, Paola; Kumar, Rajiv; Hemminki, Kari; Vodicka, Pavel

    2010-11-01

    Decreased levels of single-strand breaks in DNA (SSBs), reflecting DNA damage, have previously been observed with increased styrene exposure in contrast to a dose-dependent increase in the base-excision repair capacity. To clarify further the above aspects, we have investigated the associations between SSBs, micronuclei, DNA repair capacity and mRNA expression in XRCC1, hOGG1 and XPC genes on 71 styrene-exposed and 51 control individuals. Styrene concentrations at workplace and in blood characterized occupational exposure. The workers were divided into low (below 50 mg/m{sup 3}) and high (above 50 mg/m{sup 3}) styrene exposure groups. DNA damage and DNA repair capacity were analyzed in peripheral blood lymphocytes by Comet assay. The mRNA expression levels were determined by qPCR. A significant negative correlation was observed between SSBs and styrene concentration at workplace (R = - 0.38, p = 0.001); SSBs were also significantly higher in men (p = 0.001). The capacity to repair irradiation-induced DNA damage was the highest in the low exposure group (1.34 {+-} 1.00 SSB/10{sup 9} Da), followed by high exposure group (0.72 {+-} 0.81 SSB/10{sup 9} Da) and controls (0.65 {+-} 0.82 SSB/10{sup 9} Da). The mRNA expression levels of XRCC1, hOGG1 and XPC negatively correlated with styrene concentrations in blood and at workplace (p < 0.001) and positively with SSBs (p < 0.001). Micronuclei were not affected by styrene exposure, but were higher in older persons and in women (p < 0.001). In this study, we did not confirm previous findings on an increased DNA repair response to styrene-induced genotoxicity. However, negative correlations of SSBs and mRNA expression levels of XRCC1, hOGG1 and XPC with styrene exposure warrant further highly-targeted study.

  14. Battery, heal thyself: Inventing self-repairing batteries | Argonne...

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

    Battery, heal thyself: Inventing self-repairing batteries By Louise Lerner * January 11, 2012 Tweet EmailPrint Imagine dropping your phone on the hard concrete sidewalk-but when...

  15. Inspect and Repair Steam Traps - Steam Tip Sheet #1

    SciTech Connect (OSTI)

    2012-01-31

    This revised AMO tip sheet on inspecting and repairing steam traps provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

  16. Mechanism of DNA interstrand cross-link processing by repair...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: Mechanism of DNA interstrand cross-link processing by repair nuclease FAN1 Citation Details In-Document Search Title: Mechanism of ...

  17. To: Mansueti, Lawrence Subject: RE: Pepco Scheduled Line Repair...

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

    January 29, 2007 6:28 PM To: Mansueti, Lawrence Subject: RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Larry, Regarding the planned line outage, scheduled for Feb. 20 through Mar...

  18. Repairing Windows & Doors: How To's for the Handy Homeowner

    SciTech Connect (OSTI)

    2006-01-05

    This brochure contains tips for homeowners to repair windows and doors in their home that sustained hurricane damage. This publication is a part of the How To's for the Handy Homeowner Series.

  19. Repairing Walls & Floors: How To's for the Handy Homeowner

    SciTech Connect (OSTI)

    2006-01-09

    This brochure provides handy homeowners with tips on how to properly repair walls and floors in their homes that sustained damage during a hurricane. This publications is a part of the How To's for the Handy Homeowner Series.

  20. Intermediate hearth repair technique at Thyssen Stahl AG

    SciTech Connect (OSTI)

    Kowalski, W.; Bachhofen, H.J.; Ruether, P.; Ballewski, T.

    1996-12-31

    Nowadays various techniques for the fastest possible intermediate repair and/or emplacement of refractory materials above the tuyere level allow a significant extension of furnace campaign life. The latter are hence now exclusively determined by the service life of the hearth. The improvement of hearth monitoring and the estimation of residual brick strength of the refractory lining on the basis of temperature measurements in the hearth enable the location of individual zones of premature wear. These measurement methods, which were developed by Thyssen Stahl AG, aid the decision to undertake selective repair of the hearth. Three areas of repair are differentiated: taphole zone; hearth wall, localized; and hearth wall, extensive. This hearth repair method is described in this report using the example of hearth refurbishing blast furnace 8, Hamborn.

  1. Repairing Roofs and Ceilings: How To's for the Handy Homeowner

    SciTech Connect (OSTI)

    2006-01-01

    This brochure provides handy homeowners with tips on how to properly repair roofs and ceilings in their homes that sustained damage during a hurricane. This publications is a part of the How To's for the Handy Homeowner Series.

  2. Bearing repair services offer a cost-effective alternative to expensive replacement

    SciTech Connect (OSTI)

    2009-02-15

    The article, based on a presentation during MINExpo 2008, explains how advancement is bearing design, material, maintenance and repair methods have greatly improved the potential for and popularity of bearing repair as an effective way to extend bearing life. The Trinken Co. offers a variety of service options including repair, recertification, reconditioning and remanufacturing. Benefits of a quality repair program are outlined. 2 photos.

  3. Protein Bridges DNA Base and Nucleotide Excision Repair Pathways

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

    Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Wednesday, 28 October 2009 00:00 Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has

  4. Leak before break application in French PWR plants under operation

    SciTech Connect (OSTI)

    Faidy, C.

    1997-04-01

    Practical applications of the leak-before break concept are presently limited in French Pressurized Water Reactors (PWR) compared to Fast Breeder Reactors. Neithertheless, different fracture mechanic demonstrations have been done on different primary, auxiliary and secondary PWR piping systems based on similar requirements that the American NUREG 1061 specifications. The consequences of the success in different demonstrations are still in discussion to be included in the global safety assessment of the plants, such as the consequences on in-service inspections, leak detection systems, support optimization,.... A large research and development program, realized in different co-operative agreements, completes the general approach.

  5. Flavour symmetry breaking in the kaon parton distribution amplitude

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

    none,

    2014-11-01

    We compute the kaon's valence-quark (twist-two parton) distribution amplitude (PDA) by projecting its Poincar-covariant BetheSalpeter wave-function onto the light-front. At a scale ? = 2 GeV, the PDA is a broad, concave and asymmetric function, whose peak is shifted 1216% away from its position in QCD's conformal limit. These features are a clear expression of SU(3)-flavour-symmetry breaking. They show that the heavier quark in the kaon carries more of the bound-state's momentum than the lighter quark and also that emergent phenomena in QCD modulate the magnitude of flavour-symmetry breaking: it is markedly smaller than one might expect based on themoredifference between light-quark current masses. Our results add to a body of evidence which indicates that at any energy scale accessible with existing or foreseeable facilities, a reliable guide to the interpretation of experiment requires the use of such nonperturbatively broadened PDAs in leading-order, leading-twist formulae for hard exclusive processes instead of the asymptotic PDA associated with QCD's conformal limit. We illustrate this via the ratio of kaon and pion electromagnetic form factors: using our nonperturbative PDAs in the appropriate formulae, FK/F?=1.23 at spacelike-Q2=17 GeV2, which compares satisfactorily with the value of 0.92(5) inferred in e+e- annihilation at s=17 GeV2.less

  6. Intrinsic transverse momentum and dynamical chiral symmetry breaking

    SciTech Connect (OSTI)

    Christian Weiss, Peter Schweitzer, Mark Strikman

    2013-01-01

    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.

  7. DNA damage in cells exhibiting radiation-induced genomic instability

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

    Keszenman, Deborah J.; Kolodiuk, Lucia; Baulch, Janet E.

    2015-02-22

    Cells exhibiting radiation induced genomic instability exhibit varied spectra of genetic and chromosomal aberrations. Even so, oxidative stress remains a common theme in the initiation and/or perpetuation of this phenomenon. Isolated oxidatively modified bases, abasic sites, DNA single strand breaks and clustered DNA damage are induced in normal mammalian cultured cells and tissues due to endogenous reactive oxygen species generated during normal cellular metabolism in an aerobic environment. While sparse DNA damage may be easily repaired, clustered DNA damage may lead to persistent cytotoxic or mutagenic events that can lead to genomic instability. In this study, we tested the hypothesismore » that DNA damage signatures characterised by altered levels of endogenous, potentially mutagenic, types of DNA damage and chromosomal breakage are related to radiation-induced genomic instability and persistent oxidative stress phenotypes observed in the chromosomally unstable progeny of irradiated cells. The measurement of oxypurine, oxypyrimidine and abasic site endogenous DNA damage showed differences in non-double-strand breaks (DSB) clusters among the three of the four unstable clones evaluated as compared to genomically stable clones and the parental cell line. These three unstable clones also had increased levels of DSB clusters. The results of this study demonstrate that each unstable cell line has a unique spectrum of persistent damage and lead us to speculate that alterations in DNA damage signaling and repair may be related to the perpetuation of genomic instability.« less

  8. DNA damage in cells exhibiting radiation-induced genomic instability

    SciTech Connect (OSTI)

    Keszenman, Deborah J.; Kolodiuk, Lucia; Baulch, Janet E.

    2015-02-22

    Cells exhibiting radiation induced genomic instability exhibit varied spectra of genetic and chromosomal aberrations. Even so, oxidative stress remains a common theme in the initiation and/or perpetuation of this phenomenon. Isolated oxidatively modified bases, abasic sites, DNA single strand breaks and clustered DNA damage are induced in normal mammalian cultured cells and tissues due to endogenous reactive oxygen species generated during normal cellular metabolism in an aerobic environment. While sparse DNA damage may be easily repaired, clustered DNA damage may lead to persistent cytotoxic or mutagenic events that can lead to genomic instability. In this study, we tested the hypothesis that DNA damage signatures characterised by altered levels of endogenous, potentially mutagenic, types of DNA damage and chromosomal breakage are related to radiation-induced genomic instability and persistent oxidative stress phenotypes observed in the chromosomally unstable progeny of irradiated cells. The measurement of oxypurine, oxypyrimidine and abasic site endogenous DNA damage showed differences in non-double-strand breaks (DSB) clusters among the three of the four unstable clones evaluated as compared to genomically stable clones and the parental cell line. These three unstable clones also had increased levels of DSB clusters. The results of this study demonstrate that each unstable cell line has a unique spectrum of persistent damage and lead us to speculate that alterations in DNA damage signaling and repair may be related to the perpetuation of genomic instability.

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

    SciTech Connect (OSTI)

    Not Available

    1984-08-01

    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.

  10. Spontaneous supersymmetry breaking in two dimensional lattice super QCD

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

    Catterall, Simon; Veernala, Aarti

    2015-10-02

    We report on a non-perturbative study of two dimensional N=(2,2) super QCD. Our lattice formulation retains a single exact supersymmetry at non-zero lattice spacing, and contains Nf fermions in the fundamental representation of a U(Nc) gauge group. The lattice action we employ contains an additional Fayet-Iliopoulos term which is also invariant under the exact lattice supersymmetry. This work constitutes the first numerical study of this theory which serves as a toy model for understanding some of the issues that are expected to arise in four dimensional super QCD. As a result, we present evidence that the exact supersymmetry breaks spontaneouslymore » when Nf < Nc in agreement with theoretical expectations.« less

  11. Spontaneous supersymmetry breaking in two dimensional lattice super QCD

    SciTech Connect (OSTI)

    Catterall, Simon; Veernala, Aarti

    2015-10-02

    We report on a non-perturbative study of two dimensional N=(2,2) super QCD. Our lattice formulation retains a single exact supersymmetry at non-zero lattice spacing, and contains Nf fermions in the fundamental representation of a U(Nc) gauge group. The lattice action we employ contains an additional Fayet-Iliopoulos term which is also invariant under the exact lattice supersymmetry. This work constitutes the first numerical study of this theory which serves as a toy model for understanding some of the issues that are expected to arise in four dimensional super QCD. As a result, we present evidence that the exact supersymmetry breaks spontaneously when Nf < Nc in agreement with theoretical expectations.

  12. Radiosensitivity profiles from a panel of ovarian cancer cell lines exhibiting genetic alterations in p53 and disparate DNA-dependent protein kinase activities

    SciTech Connect (OSTI)

    Langland, Gregory T.; Yannone, Steven M.; Langland, Rachel A.; Nakao, Aki; Guan, Yinghui; Long, Sydney B.T.; Vonguyen, Lien; Chen, David J.; Gray, Joe W; Chen, Fanqing

    2009-09-07

    The variability of radiation responses in ovarian tumors and tumor-derived cell lines is poorly understood. Since both DNA repair capacity and p53 status can significantly alter radiation sensitivity, we evaluated these factors along with radiation sensitivity in a panel of sporadic human ovarian carcinoma cell lines. We observed a gradation of radiation sensitivity among these sixteen lines, with a five-fold difference in the LD50 between the most radiosensitive and the most radioresistant cells. The DNA-dependent protein kinase (DNA-PK) is essential for the repair of radiation induced DNA double-strand breaks in human somatic cells. Therefore, we measured gene copy number, expression levels, protein abundance, genomic copy and kinase activity for DNA-PK in all of our cell lines. While there were detectable differences in DNA-PK between the cell lines, there was no clear correlation with any of these differences and radiation sensitivity. In contrast, p53 function as determined by two independent methods, correlated well with radiation sensitivity, indicating p53 mutant ovarian cancer cells are typically radioresistant relative to p53 wild-type lines. These data suggest that the activity of regulatory molecules such as p53 may be better indicators of radiation sensitivity than DNA repair enzymes such as DNAPK in ovarian cancer.

  13. Española entrepreneur breaks ground; expansion will create 50 new jobs

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

    Española entrepreneur breaks ground; expansion will create 50 new jobs Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Española entrepreneur breaks ground; expansion will create 50 new jobs Governor Susana Martinez initiated new site on June 17 August 1, 2014 Breaking ground at PMI's new site. Española Mayor Alice Lucero, New Mexico Economic Development Dept. Cabinet Secretary Jon

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

    SciTech Connect (OSTI)

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

    2012-02-20

    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.

  15. Downregulation of SWI/SNF chromatin remodeling factor subunits modulates cisplatin cytotoxicity

    SciTech Connect (OSTI)

    Kothandapani, Anbarasi; Gopalakrishnan, Kathirvel; Kahali, Bhaskar; Reisman, David; Patrick, Steve M.

    2012-10-01

    Chromatin remodeling complex SWI/SNF plays important roles in many cellular processes including transcription, proliferation, differentiation and DNA repair. In this report, we investigated the role of SWI/SNF catalytic subunits Brg1 and Brm in the cellular response to cisplatin in lung cancer and head/neck cancer cells. Stable knockdown of Brg1 and Brm enhanced cellular sensitivity to cisplatin. Repair kinetics of cisplatin DNA adducts revealed that downregulation of Brg1 and Brm impeded the repair of both intrastrand adducts and interstrand crosslinks (ICLs). Cisplatin ICL-induced DNA double strand break repair was also decreased in Brg1 and Brm depleted cells. Altered checkpoint activation with enhanced apoptosis as well as impaired chromatin relaxation was observed in Brg1 and Brm deficient cells. Downregulation of Brg1 and Brm did not affect the recruitment of DNA damage recognition factor XPC to cisplatin DNA lesions, but affected ERCC1 recruitment, which is involved in the later stages of DNA repair. Based on these results, we propose that SWI/SNF chromatin remodeling complex modulates cisplatin cytotoxicity by facilitating efficient repair of the cisplatin DNA lesions. -- Highlights: Black-Right-Pointing-Pointer Stable knockdown of Brg1 and Brm enhances cellular sensitivity to cisplatin. Black-Right-Pointing-Pointer Downregulation of Brg1 and Brm impedes the repair of cisplatin intrastrand adducts and interstrand crosslinks. Black-Right-Pointing-Pointer Brg1 and Brm deficiency results in impaired chromatin relaxation, altered checkpoint activation as well as enhanced apoptosis. Black-Right-Pointing-Pointer Downregulation of Brg1 and Brm affects recruitment of ERCC1, but not XPC to cisplatin DNA lesions.

  16. Chemosensitivity of primary human fibroblasts with defective unhooking of DNA interstrand cross-links

    SciTech Connect (OSTI)

    Clingen, Peter H. . E-mail: p.clingen@ucl.ac.uk; Arlett, Colin F.; Hartley, John A.; Parris, Christopher N.

    2007-02-15

    Xeroderma pigmentosum (XP) is characterised by defects in nucleotide excision repair, ultraviolet (UV) radiation sensitivity and increased skin carcinoma. Compared to other complementation groups, XP-F patients show relatively mild cutaneous symptoms. DNA interstrand cross-linking agents are a highly cytotoxic class of DNA damage induced by common cancer chemotherapeutics such as cisplatin and nitrogen mustards. Although the XPF-ERCC1 structure-specific endonuclease is required for the repair of ICLs cellular sensitivity of primary human XP-F cells has not been established. In clonogenic survival assays, primary fibroblasts from XP-F patients were moderately sensitive to both UVC and HN2 compared to normal cells (2- to 3-fold and 3- to 5-fold, respectively). XP-A fibroblasts were considerably more sensitive to UVC (10- to 12-fold) but not sensitive to HN2. The sensitivity of XP-F fibroblasts to HN2 correlated with the defective incision or 'unhooking' step of ICL repair. Using the comet assay, XP-F cells exhibited only 20% residual unhooking activity over 24 h. Over the same time, normal and XP-A cells unhooked greater than 95% and 62% of ICLs, respectively. After HN2 treatment, ICL-associated DNA double-strand breaks (DSBs) are detected by pulse field gel electrophoresis in dividing cells. Induction and repair of DNA DSBs was normal in XP-F fibroblasts. These findings demonstrate that in primary human fibroblasts, XPF is required for the unhooking of ICLs and not for the induction or repair of ICL-associated DNA DSBs induced by HN2. In terms of cancer chemotherapy, people with mild DNA repair defects affecting ICL repair may be more prevalent in the general population than expected. Since cellular sensitivity of primary human fibroblasts usually reflects clinical sensitivity such patients with cancer would be at risk of increased toxicity.

  17. Break-Even Cost for Residential Solar Water Heating in the United...

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

    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...

  18. MicroRNAs form triplexes with double stranded DNA at sequence-specific binding sites; a eukaryotic mechanism via which microRNAs could directly alter gene expression

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

    Paugh, Steven W.; Coss, David R.; Bao, Ju; Laudermilk, Lucas T.; Grace, Christy R.; Ferreira, Antonio M.; Waddell, M. Brett; Ridout, Granger; Naeve, Deanna; Leuze, Michael Rex; et al

    2016-02-04

    MicroRNAs are important regulators of gene expression, acting primarily by binding to sequence-specific locations on already transcribed messenger RNAs (mRNA). Recent studies indicate that microRNAs may also play a role in up-regulating mRNA transcription levels, although a definitive mechanism has not been established. Double-helical DNA is capable of forming triple-helical structures through Hoogsteen and reverse Hoogsteen interactions in the major groove of the duplex, and we show physical evidence that microRNAs form triple-helical structures with duplex DNA, and identify microRNA sequences that favor triplex formation. We developed an algorithm (Trident) to search genome-wide for potential triplex-forming sites and show thatmore » several mammalian and non-mammalian genomes are enriched for strong microRNA triplex binding sites. We show that those genes containing sequences favoring microRNA triplex formation are markedly enriched (3.3 fold, p<2.2 x 10-16) for genes whose expression is positively correlated with expression of microRNAs targeting triplex binding sequences. As a result, this work has thus revealed a new mechanism by which microRNAs can interact with gene promoter regions to modify gene transcription.« less

  19. Ice plug employed on subsea pipeline bend during repair

    SciTech Connect (OSTI)

    1997-12-22

    The first controlled-temperature ice plug in the bend of an offshore gas trunkline has been carried out for Phillips Petroleum Co. Norway on its Norpipe A.S. platform in the German sector of the North Sea. The procedure was part of a subsea valve repair operation. The ice plug was successfully formed offshore and tested to a differential pressure of 1,450 psi. Repair of two valves required only 5 days during which time gas production was operating at close to 50--60% via the platform bypass, says the service company. The paper discusses the procedure.

  20. Isospin-breaking two-nucleon force with explicit {delta} excitations

    SciTech Connect (OSTI)

    Epelbaum, E.; Meissner, Ulf-G.; Krebs, H.

    2008-03-15

    We study the leading isospin-breaking contributions to the two-nucleon two-pion exchange potential due to explicit {delta} degrees of freedom in chiral effective field theory. In particular, we find important contributions due to the delta mass splittings to the charge symmetry breaking potential that act opposite to the effects induced by the nucleon mass splitting.

  1. Navy Breaks World Record With Futuristic Free-Electron Laser (FOX News.com)

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

    | Jefferson Lab Navy Breaks World Record With Futuristic Free-Electron Laser (FOX News.com) External Link: http://www.foxnews.com/scitech/2011/02/18/navy-breaks-world-record-futuristic-la... By jlab_admin on Sun, 2011-02-20

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

    SciTech Connect (OSTI)

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

    2009-12-01

    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.

  3. Methods to alter levels of a DNA repair protein

    DOE Patents [OSTI]

    Petrini, John H.; Morgan, William Francis; Maser, Richard Scott; Carney, James Patrick

    2006-10-17

    An isolated and purified DNA molecule encoding a DNA repair protein, p95, is provided, as is isolated and purified p95. Also provided are methods of detecting p95 and DNA encoding p95. The invention further provides p95 knock-out mice.

  4. Thermosetting Polymer-Matrix Composites for Strucutral Repair Applications

    SciTech Connect (OSTI)

    William Kirby Goertzen

    2007-12-01

    Several classes of thermosetting polymer matrix composites were evaluated for use in structural repair applications. Initial work involved the characterization and evaluation of woven carbon fiber/epoxy matrix composites for structural pipeline repair. Cyanate ester resins were evaluated as a replacement for epoxy in composites for high-temperature pipe repair applications, and as the basis for adhesives for resin infusion repair of high-temperature composite materials. Carbon fiber/cyanate ester matrix composites and fumed silica/cyanate ester nanocomposites were evaluated for their thermal, mechanical, viscoelastic, and rheological properties as they relate to their structure, chemistry, and processing characteristics. The bisphenol E cyanate ester under investigation possesses a high glass transition temperature, excellent mechanical properties, and unique ambient temperature processability. The incorporate of fumed silica served to enhance the mechanical and rheological properties of the polymer and reduce thermal expansion without sacrificing glass transition or drastically altering curing kinetics. Characterization of the composites included dynamic mechanical analysis, thermomechanical analysis, differential scanning calorimetry, thermogravimetric analysis, rheological and rheokinetic evaluation, and transmission electron microscopy.

  5. Sea quark transverse momentum distributions and dynamical chiral symmetry breaking

    SciTech Connect (OSTI)

    Schweitzer, Peter; Strikman, Mark; Weiss, Christian

    2014-01-01

    Recent theoretical studies have provided new insight into the intrinsic transverse momentum distributions of valence and sea quarks in the nucleon at a low scale. The valence quark transverse momentum distributions (q - qbar) are governed by the nucleon's inverse hadronic size R{sup -1} ~ 0.2 GeV and drop steeply at large p{sub T}. The sea quark distributions (qbar) are in large part generated by non-perturbative chiral-symmetry breaking interactions and extend up to the scale rho{sup -1} ~ 0.6 GeV. These findings have many implications for modeling the initial conditions of perturbative QCD evolution of TMD distributions (starting scale, shape of p{sub T}. distributions, coordinate-space correlation functions). The qualitative difference between valence and sea quark intrinsic p{sub T}. distributions could be observed experimentally, by comparing the transverse momentum distributions of selected hadrons in semi-inclusive deep-inelastic scattering, or those of dileptons produced in pp and pbar-p scattering.

  6. Can quantum coherent solar cells break detailed balance?

    SciTech Connect (OSTI)

    Kirk, Alexander P.

    2015-07-21

    Carefully engineered coherent quantum states have been proposed as a design attribute that is hypothesized to enable solar photovoltaic cells to break the detailed balance (or radiative) limit of power conversion efficiency by possibly causing radiative recombination to be suppressed. However, in full compliance with the principles of statistical mechanics and the laws of thermodynamics, specially prepared coherent quantum states do not allow a solar photovoltaic cell—a quantum threshold energy conversion device—to exceed the detailed balance limit of power conversion efficiency. At the condition given by steady-state open circuit operation with zero nonradiative recombination, the photon absorption rate (or carrier photogeneration rate) must balance the photon emission rate (or carrier radiative recombination rate) thus ensuring that detailed balance prevails. Quantum state transitions, entropy-generating hot carrier relaxation, and photon absorption and emission rate balancing are employed holistically and self-consistently along with calculations of current density, voltage, and power conversion efficiency to explain why detailed balance may not be violated in solar photovoltaic cells.

  7. Treatment methods for breaking certain oil and water emulsions

    DOE Patents [OSTI]

    Sealock, Jr., L. John; Baker, Eddie G.; Elliott, Douglas C.

    1992-01-01

    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.

  8. Development of quick repairing technique for ceramic burner in hot stove of blast furnace

    SciTech Connect (OSTI)

    Kondo, Atsushi; Doura, Kouji; Nakamura, Hirofumi

    1997-12-31

    Refractories of ceramic burner in hot stoves at Wakayama No. 4 blast furnace were damaged. There are only three hot stoves, so repairing must be done in a short. Therefore, a quick repairing technique for ceramic burners has been developed, and two ceramic burners were repaired in just 48 hours.

  9. Particle-Hole Symmetry Breaking in the Pseudogap State of Bi2201

    SciTech Connect (OSTI)

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

    2011-08-19

    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.

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

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

    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

  11. Dynamics of Peccei-Quinn breaking field after inflation and axion isocurvature perturbations

    SciTech Connect (OSTI)

    Harigaya, Keisuke; Ibe, Masahiro; Kawasaki, Masahiro; Yanagida, Tsutomu T.

    2015-11-04

    The Peccei-Quinn mechanism suffers from the problem of the isocurvature perturbations. The isocurvature perturbations are suppressed if the Peccei-Quinn breaking scale is large during inflation. The oscillation of the Peccei-Quinn breaking field after inflation, however, leads to the formation of domain walls due to the parametric resonance effect. In this paper, we discuss the evolution of the Peccei-Quinn breaking field after inflation in detail, and propose a model where the parametric resonance is ineffective and hence domain walls are not formed. We also discuss consistency of our model with supersymmetric theory.

  12. U.S. Department of Energy Breaks Ground on State-of-the-Art Wind Turbine

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

    Test Facility | Department of Energy Breaks Ground on State-of-the-Art Wind Turbine Test Facility U.S. Department of Energy Breaks Ground on State-of-the-Art Wind Turbine Test Facility October 1, 2012 - 12:08pm Addthis This is an excerpt from the Third Quarter 2012 edition of the Wind Program R&D Newsletter. The U.S. Department of Energy (DOE) joined with Texas Tech University (TTU) and Sandia National Laboratories (SNL) in July 2012 to break ground on a new state-of-the-art wind turbine

  13. Cycling with BRCA2 from DNA repair to mitosis

    SciTech Connect (OSTI)

    Lee, Hyunsook

    2014-11-15

    Genetic integrity in proliferating cells is guaranteed by the harmony of DNA replication, appropriate DNA repair, and segregation of the duplicated genome. Breast cancer susceptibility gene BRCA2 is a unique tumor suppressor that is involved in all three processes. Hence, it is critical in genome maintenance. The functions of BRCA2 in DNA repair and homology-directed recombination (HDR) have been reviewed numerous times. Here, I will briefly go through the functions of BRCA2 in HDR and focus on the emerging roles of BRCA2 in telomere homeostasis and mitosis, then discuss how BRCA2 exerts distinct functions in a cell-cycle specific manner in the maintenance of genomic integrity. - Highlights: • BRCA2 is a multifaceted tumor suppressor and is crucial in genetic integrity. • BRCA2 exerts distinct functions in cell cycle-specific manner. • Mitotic kinases regulate diverse functions of BRCA2 in mitosis and cytokinesis.

  14. Thermostatic/orifice trap reduces fuel, repair costs

    SciTech Connect (OSTI)

    Not Available

    1982-11-01

    This article is an evaluation of a steam trap that combines the continuous drain oriface with a thermostatically controlled trap oriface to efficiently remove condensate from virtually any steam system within its operating limits. This trap effectively reduces fuel and repair costs and has a capacity of 6000 il/hr, handles various pressures up to 600 psig, and operates against back pressures up to 90% of inlet pressure.

  15. Protein Bridges DNA Base and Nucleotide Excision Repair Pathways

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

    Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps

  16. Protein Bridges DNA Base and Nucleotide Excision Repair Pathways

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

    Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps

  17. Protein Bridges DNA Base and Nucleotide Excision Repair Pathways

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

    Protein Bridges DNA Base and Nucleotide Excision Repair Pathways Print Alkyltransferase proteins (AGT) protect cells from the biological effects of DNA damage caused by the addition of alkyl groups (alkylation). Alkyltransferase-like proteins (ATLs) can do the same, but they lack the reactive cysteine residue that allows the alkyltransferase function, and the mechanism for cell protection has remained unknown. To address this mystery, a British-American team lead by researchers at the Scripps

  18. San Carlos Apache Tribe Set to Break Ground on New Solar Project...

    Energy Savers [EERE]

    This spring, the San Carlos Apache Tribe is planning to break ground on a new tribally financed and owned 1.1-megawatt (MW) solar photovoltaic (PV) array. The PV system will ...

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

    SciTech Connect (OSTI)

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

    2011-07-01

    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.

  20. Dynamics of Peccei-Quinn breaking field after inflation and axion...

    Office of Scientific and Technical Information (OSTI)

    In this paper, we discuss the evolution of the Peccei-Quinn breaking field after inflation in detail, and propose a model where the parametric resonance is ineffective and hence ...

  1. Detection of a Spectral Break in the Extra Hard Component of...

    Office of Scientific and Technical Information (OSTI)

    the Extra Hard Component of GRB 090926A Citation Details In-Document Search Title: Detection of a Spectral Break in the Extra Hard Component of GRB 090926A You are accessing a ...

  2. Fermi-LAT Detection of a Break in the Gamma-Ray Spectrum of the...

    Office of Scientific and Technical Information (OSTI)

    in the Gamma-Ray Spectrum of the Supernova Remnant Cassiopeia A Citation Details In-Document Search Title: Fermi-LAT Detection of a Break in the Gamma-Ray Spectrum of the Supernova ...

  3. More than $3 million raised during record-breaking Employee Giving Campaign

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

    Record-breaking employee giving campaign Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit More than $3 million raised during record-breaking Employee Giving Campaign Contributions will benefit regional nonprofits December 1, 2014 Mobile medical and dental clinic owned by Tierra Amarillas' La Clinica del Pueblo de Rio Arriba. The purchase of the vehicle was made possible by donations

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

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

    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

  5. Novel Thermal Break with Simplified Manufacturing for R7 Commercial Windows

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

    | Department of Energy Thermal Break with Simplified Manufacturing for R7 Commercial Windows Novel Thermal Break with Simplified Manufacturing for R7 Commercial Windows Image courtesy of Alcoa and BTO Peer Review. Image courtesy of Alcoa and BTO Peer Review. Lead Performer: Alcoa - Pittsburgh, PA DOE Funding: $1,123,838 Cost Share: $280,960 Project Term: October 2014 - September 2016 Funding Opportunity: Building Energy Efficiency Frontiers and Incubator Technologies (BENEFIT) - 2014

  6. Metallic glass could make your next cell phone harder to break

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

    Metallic glass could make your next cell phone harder to break Alumni Link: Opportunities, News and Resources for Former Employees Latest Issue:September 2015 all issues All Issues » submit Metallic glass could make your next cell phone harder to break Lab researcher works to rearrange the atoms in metals June 20, 2014 New insights to changing the atomic structure of metals New insights to changing the atomic structure of metals Contact Linda Anderman Email Metal and glass objects are all

  7. Energy Department Announces $12 Million to Accelerate Record-Breaking Solar

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

    Cell Efficiency | Department of Energy 2 Million to Accelerate Record-Breaking Solar Cell Efficiency Energy Department Announces $12 Million to Accelerate Record-Breaking Solar Cell Efficiency January 25, 2013 - 3:41pm Addthis As part of the Energy Department's SunShot Initiative, the Department today announced $12 million to develop innovative, ultra-efficient solar devices that will close the gap with the theoretical efficiency limit, or the highest potential percentage of sunlight

  8. Breaking Ground and Driving Discovery | U.S. DOE Office of Science (SC)

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

    Breaking Ground and Driving Discovery News News Home Featured Articles 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 Science Headlines Science Highlights Presentations & Testimony News Archives Communications and Public Affairs Contact Information Office of Science U.S. Department of Energy 1000 Independence Ave., SW Washington, DC 20585 P: (202) 586-5430 12.16.11 Breaking Ground and Driving Discovery Director Brinkman welcomes the Illinois Accelerator Research Center. Print

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

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

    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

  10. Bubbles Help Break Energy Storage Record for Lithium Air-Batteries

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (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 batteries that holds promise for electric vehicles January 25, 2012 Linda Vu, lvu@lbl.gov, +1 510 495 2402 Using a new approach, the team built a graphene membrane for use in lithium-air batteries, which could, one day, replace conventional batteries in electric vehicles. Resembling coral, this porous graphene material

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

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

    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

  12. Helping STEM Education Take Root: Breaking Ground on a Field Station in

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

    Indian Country | Department of Energy Helping STEM Education Take Root: Breaking Ground on a Field Station in Indian Country Helping STEM Education Take Root: Breaking Ground on a Field Station in Indian Country November 7, 2012 - 10:50am Addthis (From Left) Stuart Harris, Confederated Tribes of the Umatilla Indian Reservation, Director of the Department of Science and Engineering, Dave Huizenga, Senior Advisor for the Office of Environmental Management, and Tracey LeBeau, Director of the

  13. Induction and Persistence of Large ?H2AX Foci by High Linear Energy Transfer Radiation in DNA-Dependent protein kinaseDeficient Cells

    SciTech Connect (OSTI)

    Bracalente, Candelaria; Ibaez, Irene L.; Molinari, Beatriz; Palmieri, Mnica; Kreiner, Andrs; Valda, Alejandro; and others

    2013-11-15

    Purpose: To evaluate the cell response to DNA double-strand breaks induced by low and high linear energy transfer (LET) radiations when the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), an essential protein of the nonhomologous end-joining repair pathway, lacks kinase activity. Methods and Materials: CHO10B2, a Chinese hamster ovary cell line, and its derived radiosensitive mutant cell line, irs-20, lacking DNA-PKcs activity, were evaluated after 0 to 3 Gy of ?-rays, plateau and Bragg peak protons, and lithium beams by clonogenic assay, and as a measurement of double-strand breaks, phosphorylated H2AX (?H2AX) foci number and size were quantified by immunocytofluorescence. Results: Irs-20 exhibited greater radiosensitivity and a higher amount of ?H2AX foci than CHO10B2 at 6 hours after irradiation for all types of radiations. Remarkably, CHO10B2 and irs-20 maintained their difference in radiosensitivity after high-LET radiation. Six hours after low-LET radiations, irs-20 did not reach basal levels of ?H2AX at high doses, whereas CHO10B2 recovered basal levels for all doses. After high-LET radiation, only CHO10B2 exhibited a reduction in ?H2AX foci, but it never reached basal levels. Persistent foci in irs-20 confirmed a repair deficiency. Interestingly, after 30 minutes of high-LET radiation both cell lines exhibited large foci (size >0.9 ?m{sup 2}) related to the damage nature, whereas at 6 hours irs-20 showed a higher amount of large foci than CHO10B2, with a 7-fold increase at 3 Gy, that could also be associated to radiosensitivity. Conclusions: We demonstrated, for the first time, an association between deficient DNA-PKcs activity and not only high levels of H2AX phosphorylation but also persistence and size increase of ?H2AX foci after high-LET irradiation.

  14. Blade reliability collaborative : collection of defect, damage and repair data.

    SciTech Connect (OSTI)

    Ashwill, Thomas D.; Ogilvie, Alistair B.; Paquette, Joshua A.

    2013-04-01

    The Blade Reliability Collaborative (BRC) was started by the Wind Energy Technologies Department of Sandia National Laboratories and DOE in 2010 with the goal of gaining insight into planned and unplanned O&M issues associated with wind turbine blades. A significant part of BRC is the Blade Defect, Damage and Repair Survey task, which will gather data from blade manufacturers, service companies, operators and prior studies to determine details about the largest sources of blade unreliability. This report summarizes the initial findings from this work.

  15. One "Cool Tool" That's Helping Repair Your DNA | Department of Energy

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

    "Cool Tool" That's Helping Repair Your DNA One "Cool Tool" That's Helping Repair Your DNA April 18, 2011 - 1:20pm Addthis Charles Rousseaux Charles Rousseaux Senior Communications Specialist (detailee) What are the key facts? Berkeley Lab's Advanced Light Source produces x-ray light that shines a billion times bright than the sun. Scientists discovered the motor that drives the actual repair of the DNA repair machine called MRN, which is tethered to the rest of the machine in

  16. adaptation of DNA repair Byrne, Rose T; Klingele, Audrey J; Cabot...

    Office of Scientific and Technical Information (OSTI)

    Evolution of extreme resistance to ionizing radiation via genetic adaptation of DNA repair Byrne, Rose T; Klingele, Audrey J; Cabot, Eric L; Schackwitz, Wendy S; Martin, Jeffrey A;...

  17. WPN 12-9: Weatherization Assistance Program Incidental Repair Measure Guidance

    Broader source: Energy.gov [DOE]

    To provide guidance on incidental repair measures (IRM) allowable under the U.S. Department of Energy Weatherization Assistance Program (WAP).

  18. Brain necrosis after fractionated radiation therapy: Is the halftime for repair longer than we thought?

    SciTech Connect (OSTI)

    Bender, Edward T.

    2012-11-15

    Purpose: To derive a radiobiological model that enables the estimation of brain necrosis and spinal cord myelopathy rates for a variety of fractionation schemes, and to compare repair effects between brain and spinal cord. Methods: Sigmoidal dose response relationships for brain radiation necrosis and spinal cord myelopathy are derived from clinical data using nonlinear regression. Three different repair models are considered and the repair halftimes are included as regression parameters. Results: For radiation necrosis, a repair halftime of 38.1 (range 6.9-76) h is found with monoexponential repair, while for spinal cord myelopathy, a repair halftime of 4.1 (range 0-8) h is found. The best-fit alpha beta ratio is 0.96 (range 0.24-1.73)Conclusions: A radiobiological model that includes repair corrections can describe the clinical data for a variety of fraction sizes, fractionation schedules, and total doses. Modeling suggests a relatively long repair halftime for brain necrosis. This study suggests that the repair halftime for late radiation effects in the brain may be longer than is currently thought. If confirmed in future studies, this may lead to a re-evaluation of radiation fractionation schedules for some CNS diseases, particularly for those diseases where fractionated stereotactic radiation therapy is used.

  19. Building America Top Innovations 2013 Profile – Window Replacement, Rehabilitation, & Repair Guide

    SciTech Connect (OSTI)

    none,

    2013-09-01

    In this Top Innovation profile, Building Science Corporation guides contractors through several options for repairing or replacing old windows to improve air sealing and thermal performance.

  20. Best Management Practice #3: Distribution System Audits, Leak Detection, and Repair

    Broader source: Energy.gov [DOE]

    A distribution system audit, or leak detection and repair program, may help federal facilities identify and reduce water losses and be better stewards of water as a resource.

  1. Symmetry breaking indication for supergravity inflation in light of the Planck 2015

    SciTech Connect (OSTI)

    Li, Tianjun; Li, Zhijin; Nanopoulos, Dimitri V.

    2015-09-01

    Supergravity (SUGRA) theories with exact global U(1) symmetry or shift symmetry in Kähler potential provide natural frameworks for inflation. However, quadratic inflation is disfavoured by the new results on primordial tensor fluctuations from the Planck Collaboration. To be consistent with the new Planck data, we point out that the explicit symmetry breaking is needed, and study these two SUGRA inflation in detail. For SUGRA inflation with global U(1) symmetry, the symmetry breaking term leads to a trigonometric modulation on inflaton potential. Coefficient of the U(1) symmetry breaking term is of order 10{sup −2}, which is sufficient large to improve the inflationary predictions while its higher order corrections are negligible. Such models predict sizeable tensor fluctuations and highly agree with the Planck results. In particular, the model with a linear U(1) symmetry breaking term predicts the tensor-to-scalar ratio around r∼0.01 and running spectral index α{sub s}∼−0.004, which comfortably fit with the Planck observations. For SUGRA inflation with breaking shift symmetry, the inflaton potential is modulated by an exponential factor. The modulated linear and quadratic models are consistent with the Planck observations. In both types of models the tensor-to-scalar ratio can be of order 10{sup −2}, which will be tested by the near future observations.

  2. The evolution of the break preclusion concept for nuclear power plants in Germany

    SciTech Connect (OSTI)

    Schulz, H.

    1997-04-01

    In the updating of the Guidelines for PWR`s of the {open_quotes}Reaktor-Sicherheitskommission{close_quotes} (RSK) in 1981 the requirements on the design have been changed with respect to the postulated leaks and breaks in the primary pressure boundary. The major change was a revision in the requirements for pipe whip protection. As a logical consequence of the {open_quotes}concept of basic safety{close_quotes} a guillotine type break or any other break type resulting in a large opening is not postulated any longer for the calculation of reaction and jet forces. As an upper limit for a leak an area of 0, 1 A (A = open cross section of the pipe) is postulated. This decision was based on a general assessment of the present PWR system design in Germany. Since then a number of piping systems have been requalified in the older nuclear power plants to comply with the break preclusion concept. Also a number of extensions of the concept have been developed to cover also leak-assumptions for branch pipes. Furthermore due considerations have been given to other aspects which could contribute to a leak development in the primary circuit, like vessel penetrations, manhole covers, flanges, etc. Now the break preclusion concept originally applied to the main piping has been developed into an integrated concept for the whole pressure boundary within the containment and will be applied also in the periodic safety review of present nuclear power plants.

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

    SciTech Connect (OSTI)

    Oike, Takahiro; Division of Genome Biology, National Cancer Center Research Institute, Chuo-ku, Tokyo; Department of Radiation Oncology, Gunma University Graduate School of Medicine, Maebashi, Gunma ; Ogiwara, Hideaki; Torikai, Kohta; Nakano, Takashi; Yokota, Jun; Kohno, Takashi

    2012-11-01

    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

  4. Soft A4→Z3 symmetry breaking and cobimaximal neutrino mixing

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

    Ma, Ernest

    2016-03-28

    In this study, I propose a model of radiative charged-lepton and neutrino masses with A4 symmetry. The soft breaking of A4 to Z3 lepton triality is accomplished by dimension-three terms. The breaking of Z3 by dimension-two terms allows cobimaximal neutrino mixing (θ13 ≠ 0, θ23 = π/4, δcp=π/2) to be realized with only very small finite calculable deviations from the residual Z3 lepton triality. This construction solves a long-standing technical problem inherent in renormalizable A4 models since their inception.

  5. Media Advisory Jefferson Lab Breaks Ground Sept. 1 for $73 Million

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

    Technology & Engineering Facility | Jefferson Lab Jefferson Lab Breaks Ground Sept. 1 for $73 Million Technology &amp; Engineering Facility Media Advisory Jefferson Lab Breaks Ground Sept. 1 for $73 Million Technology & Engineering Facility Date: Wednesday, Sept. 1, 2010 Time: 9 - 10 a.m. News media representatives are asked to arrive no later than 8:45 a.m. to allow time to get in place for the event. Place: Jefferson Lab, 12000 Jefferson Avenue, Newport News, VA 23606 Event:

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

    SciTech Connect (OSTI)

    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)

    2012-10-15

    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.

  7. The concepts of leak before break and absolute reliability of NPP equipment and piping

    SciTech Connect (OSTI)

    Getman, A.F.; Komarov, O.V.; Sokov, L.M.

    1997-04-01

    This paper describes the absolute reliability (AR) concept for ensuring safe operation of nuclear plant equipment and piping. The AR of a pipeline or component is defined as the level of reliability when the probability of an instantaneous double-ended break is near zero. AR analysis has been applied to Russian RBMK and VVER type reactors. It is proposed that analyses required for application of the leak before break concept should be included in AR implementation. The basic principles, methods, and approaches that provide the basis for implementing the AR concept are described.

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

    SciTech Connect (OSTI)

    Pepe, M.; Wiese, U.-J.

    2009-05-15

    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.

  9. The influence of pairing correlations on the isospin symmetry breaking corrections of superallowed Fermi beta decays

    SciTech Connect (OSTI)

    Cal Latin-Small-Letter-Dotless-I k, A. E.; Gerceklioglu, M.; Selam, C.

    2013-05-15

    Within the framework of quasi-particle random phase approximation, the isospin breaking correction of superallowed 0{sup +} {yields} 0{sup +} beta decay and unitarity of Cabibbo-Kobayashi-Maskawa mixing matrix have been investigated. The broken isotopic symmetry of nuclear part of Hamiltonian has been restored by Pyatov's method. The isospin symmetry breaking correction with pairing correlations has been compared with the previous results without pairing. The effect of pairing interactions has been examined for nine superallowed Fermi beta decays; their parent nuclei are {sup 26}Al, {sup 34}Cl, {sup 38}K, {sup 42}Sc, {sup 46}V, {sup 50}Mn, {sup 54}Co, {sup 62}Ga, {sup 74}Rb.

  10. Injection repair of carbon fiber/bismaleimide composite panels with bisphenol E cyanate ester resin

    SciTech Connect (OSTI)

    Thunga, Mahendra; Bauer, Amy; Obusek, Kristine; Meilunas, Ray; Akinc, Mufit; Kessler, Michael R

    2014-08-01

    Resin injection of bisphenol E cyanate ester, a low viscosity resin that cures into a high temperature thermoset polymer, is investigated as a reliable repair method to restore strength and stiffness in delaminated carbon fiber/bismaleimide composites used in aircraft panels. The influence of temperature on the viscosity of the uncured resin was measured to optimize the injection conditions for high resin infiltration into the delaminations. The repair efficiency of the resin was evaluated by varying the panel thickness and the method by which the delamination damage was created in the composite specimens. Ultrasonic scanning (C-scan), flash thermography images, and cross-section analysis of repaired panels revealed excellent resin infiltration into the damaged region. Evaluation of mechanical repair efficiency using both bending stiffness and in-plain compressive strength of the composite panels as the repair metrics showed values exceeding 100%.

  11. Composite vascular repair grafts via micro-imprinting and electrospinning

    SciTech Connect (OSTI)

    Liu, Yuanyuan Hu, Qingxi; Xiang, Ke Chen, Haiping Li, Yu

    2015-04-15

    Composite vascular grafts formed by micro-imprinting and electrospinning exhibited improved mechanical properties relative to those formed by electrospinning alone. The three-layered composite grafts mimic the three-layered structure of natural blood vessels. The middle layer is made by micro-imprinting poly-p-dioxanone (PPDO), while the inner and outer layers are electrospun mixtures of chitosan and polyvinyl alcohol. The graft morphology is characterized with scanning electron microscopy. For constant graft thicknesses, the PPDO increases the mechanical strength. Cells cultivated on the vascular grafts adhere and proliferate better because of the natural, biological chitosan in the inner and outer layers. Overall, the composite scaffolds could be good candidates for blood vessel repair.

  12. Method of tissue repair using a composite material

    DOE Patents [OSTI]

    Hutchens, Stacy A.; Woodward, Jonathan; Evans, Barbara R.; O'Neill, Hugh M.

    2016-03-01

    A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

  13. Method of tissue repair using a composite material

    DOE Patents [OSTI]

    Hutchens, Stacy A; Woodward, Jonathan; Evans, Barbara R; O'Neill, Hugh M

    2014-03-18

    A composite biocompatible hydrogel material includes a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa. A calcium comprising salt is disposed in at least some of the pores. The porous polymer matrix can comprise cellulose, including bacterial cellulose. The composite can be used as a bone graft material. A method of tissue repair within the body of animals includes the steps of providing a composite biocompatible hydrogel material including a porous polymer matrix, the polymer matrix including a plurality of pores and providing a Young's modulus of at least 10 GPa, and inserting the hydrogel material into cartilage or bone tissue of an animal, wherein the hydrogel material supports cell colonization in vitro for autologous cell seeding.

  14. Coherent States and Spontaneous Symmetry Breaking in Light Front Scalar Field Theory

    SciTech Connect (OSTI)

    Vary, J.P.; Chakrabarti, D.; Harindranath, A.; Lloyd, R.; Martinovic, L.; Spence, J.R.; /Iowa State U.

    2005-12-14

    Recently developed nuclear many-body techniques provide novel results when applied to constituent quark models and to light-front scalar field theory. We show how spontaneous symmetry breaking arises and is consistent with a coherent state ansatz in a variational treatment. The kink and the kink-antikink topological features are identified and the onset of symmetry restoration is demonstrated.

  15. Entropic information for travelling solitons in Lorentz and CPT breaking systems

    SciTech Connect (OSTI)

    Correa, R.A.C.; Rocha, Roldão da; Souza Dutra, A. de

    2015-08-15

    In this work we group four research topics apparently disconnected, namely solitons, Lorentz symmetry breaking, supersymmetry, and entropy. Following a recent work (Gleiser and Stamatopoulos, 2012), we show that it is possible to construct in the context of travelling wave solutions a configurational entropy measure in functional space, from the field configurations. Thus, we investigate the existence and properties of travelling solitons in Lorentz and CPT breaking scenarios for a class of models with two interacting scalar fields. Here, we obtain a complete set of exact solutions for the model studied which display both double and single-kink configurations. In fact, such models are very important in applications that include Bloch branes, Skyrmions, Yang–Mills, Q-balls, oscillons and various superstring-motivated theories. We find that the so-called Configurational Entropy (CE) for travelling solitons shows that the best value of parameter responsible to break the Lorentz symmetry is one where the energy density is distributed equally around the origin. In this way, the information-theoretical measure of travelling solitons in Lorentz symmetry violation scenarios opens a new window to probe situations where the parameters responsible for breaking the symmetries are arbitrary. In this case, the CE selects the best value of the parameter in the model.

  16. Long distance high power optical laser fiber break detection and continuity monitoring systems and methods

    DOE Patents [OSTI]

    Rinzler, Charles C.; Gray, William C.; Faircloth, Brian O.; Zediker, Mark S.

    2016-02-23

    A monitoring and detection system for use on high power laser systems, long distance high power laser systems and tools for performing high power laser operations. In particular, the monitoring and detection systems provide break detection and continuity protection for performing high power laser operations on, and in, remote and difficult to access locations.

  17. WHERE DOES FLUID-LIKE TURBULENCE BREAK DOWN IN THE SOLAR WIND?

    SciTech Connect (OSTI)

    Perri, S.; Carbone, V.; Veltri, P.

    2010-12-10

    Power spectra of the magnetic field in solar wind display a Kolmogorov law f {sup -5/3} at intermediate range of frequencies f, say within the inertial range. Two spectral breaks are also observed: one separating the inertial range from an f {sup -1} spectrum at lower frequencies, and another one between the inertial range and an f {sup -7/3} spectrum at higher frequencies. The breaking of fluid-like turbulence at high frequencies has been attributed to either the occurrence of kinetic Alfven wave fluctuations above the ion-cyclotron frequency or to whistler turbulence above the frequency corresponding to the proton gyroradius. Using solar wind data, we show that the observed high-frequency spectral break seems to be independent of the distance from the Sun, and then of both the ion-cyclotron frequency and the proton gyroradius. We suppose that the observed high-frequency break could be either caused by a combination of different physical processes or associated with a remnant signature of coronal turbulence.

  18. Development and validation of bonded composite doubler repairs for commercial aircraft.

    SciTech Connect (OSTI)

    Roach, Dennis Patrick; Rackow, Kirk A.

    2007-07-01

    A typical aircraft can experience over 2,000 fatigue cycles (cabin pressurizations) and even greater flight hours in a single year. An unavoidable by-product of aircraft use is that crack, impact, and corrosion flaws develop throughout the aircraft's skin and substructure elements. Economic barriers to the purchase of new aircraft have placed even greater demands on efficient and safe repair methods. The use of bonded composite doublers offers the airframe manufacturers and aircraft maintenance facilities a cost effective method to safely extend the lives of their aircraft. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is now possible to bond a single Boron-Epoxy composite doubler to the damaged structure. The FAA's Airworthiness Assurance Center at Sandia National Labs (AANC), Boeing, and Federal Express completed a pilot program to validate and introduce composite doubler repair technology to the U.S. commercial aircraft industry. This project focused on repair of DC-10 fuselage structure and its primary goal was to demonstrate routine use of this repair technology using niche applications that streamline the design-to-installation process. As composite doubler repairs gradually appear in the commercial aircraft arena, successful flight operation data is being accumulated. These commercial aircraft repairs are not only demonstrating the engineering and economic advantages of composite doubler technology but they are also establishing the ability of commercial maintenance depots to safely adopt this repair technique. This report presents the array of engineering activities that were completed in order to make this technology available for widespread commercial aircraft use. Focused laboratory testing was conducted to compliment the field data and to address specific issues regarding damage tolerance and flaw growth in composite doubler repairs. Fatigue and strength tests were performed on a simulated wing repair using a

  19. Effect of multiple repairs in girth welds of pipelines on the mechanical properties

    SciTech Connect (OSTI)

    Vega, O.E.; Hallen, J.M.; Villagomez, A.

    2008-10-15

    This work presents the results of multiple weld repairs in the same area in seamless API X-52 microalloyed steel pipe. Four conditions of shielded metal arc welding repairs and one as-welded specimen of the girth weld were characterized to determine changes in the microstructure, grain size in the heat affected zone, and to evaluate their effect on the mechanical properties of the weld joints. The mechanical properties by means of tension tests, Charpy-V impact resistance and Vickers hardness of the welds were analyzed. The results indicate that significant changes are not generated in the microstructural constituents of the heat affected zone. Grain growth in the heat affected zone at the specimen mid-thickness with the number of repairs was observed. Tensile strength of the weld joints meets the requirement of the API 1104 standard even after the fourth weld repair. Significant reduction in Charpy-V impact resistance with the number of weld repairs was found when the notch location was in the intersection of the fusion line with the specimen mid-thickness. A significant increase in the Vickers hardness of the heat affected zone occurred after the first repair and a gradual decrease in the Vickers hardness occurred as the number of repairs increases.

  20. CDK1 enhances mitochondrial bioenergetics for radiation-induced DNA repair

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

    Qin, Lili; Fan, Ming; Candas, Demet; Jiang, Guochun; Papadopoulos, Stelios; Tian, Lin; Woloschak, Gayle; Grdina, David J.; Li, Jian  Jian

    2015-12-06

    Nuclear DNA repair capacity is a critical determinant of cell fate under genotoxic stress conditions. DNA repair is a well-defined energy-consuming process. However, it is unclear how DNA repair is fueled and whether mitochondrial energy production contributes to nuclear DNA repair. Here, we report a dynamic enhancement of oxygen consumption and mitochondrial ATP generation in irradiated normal cells, paralleled with increased mitochondrial relocation of the cell-cycle kinase CDK1 and nuclear DNA repair. The basal and radiation-induced mitochondrial ATP generation is reduced significantly in cells harboring CDK1 phosphorylation-deficient mutant complex I subunits. Similarly, mitochondrial ATP generation and nuclear DNA repair aremore »also compromised severely in cells harboring mitochondrially targeted, kinase-deficient CDK1. These findings demonstrate a mechanism governing the communication between mitochondria and the nucleus by which CDK1 boosts mitochondrial bioenergetics to meet the increased cellular fuel demand for DNA repair and cell survival under genotoxic stress conditions.« less

  1. DNA repair of a single UV photoproduct in a designed nucleosome

    SciTech Connect (OSTI)

    Kosmoskil, Joseph V.; Ackerman, Eric J. ); Smerdon, Michael J.

    2001-08-28

    Eukaryotic DNA repair enzymes must interact with the architectural hierarchy of chromatin. The challenge of finding damaged DNA complexed with histone proteins in nucleosomes is complicated by the need to maintain local chromatin structures involved in regulating other DNA processing events. The heterogeneity of lesions induced by DNA-damaging agents has led us to design homogeneously damaged substrates to directly compare repair of naked DNA with that of nucleosomes. Here we report that nucleotide excision repair in Xenopus nuclear extracts can effectively repair a single UV radiation photoproduct located 5 bases from the dyad center of a positioned nucleosome, although the nucleosome is repaired at about half the rate at which the naked DNA fragment is. Extract repair within the nucleosome is > 50-fold more rapid than either enzymatic photoreversal or endonuclease cleavage of the lesion in vitro. Furthermore, nucleosome formation occurs (after repair) only on damaged naked DNA ( 165-bp fragments) during a 1-h incubation in these extracts, even in the presence of a large excess of undamaged DNA. This is an example of selective nucleosome assembly by Xenopus nuclear extracts on a short linear DNA fragment containing a DNA lesion.

  2. Fabrication Flaw Density and Distribution In Repairs to Reactor Pressure Vessel and Piping Welds

    SciTech Connect (OSTI)

    GJ Schuster, FA Simonen, SR Doctor

    2008-04-01

    The Pacific Northwest National Laboratory is developing a generalized fabrication flaw distribution for the population of nuclear reactor pressure vessels and for piping welds in U.S. operating reactors. The purpose of the generalized flaw distribution is to predict component-specific flaw densities. The estimates of fabrication flaws are intended for use in fracture mechanics structural integrity assessments. Structural integrity assessments, such as estimating the frequency of loss-of-coolant accidents, are performed by computer codes that require, as input, accurate estimates of flaw densities. Welds from four different reactor pressure vessels and a collection of archived pipes have been studied to develop empirical estimates of fabrication flaw densities. This report describes the fabrication flaw distribution and characterization in the repair weld metal of vessels and piping. This work indicates that large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the ends of the repair cavities. Parametric analysis using an exponential fit is performed on the data. The relevance of construction records is established for describing fabrication processes and product forms. An analysis of these records shows there was a significant change in repair frequency over the years when these components were fabricated. A description of repair flaw morphology is provided with a discussion of fracture mechanics significance. Fabrication flaws in repairs are characterized using optimized-access, high-sensitivity nondestructive ultrasonic testing. Flaw characterizations are then validated by other nondestructive evaluation techniques and complemented by destructive testing.

  3. the Adaptive Response, Genetic Haplo-Insufficiency and Genomic Instability

    SciTech Connect (OSTI)

    Geard, Charles R.

    2014-12-12

    The linear no-threshold (LNT) hypothesis is the driving force in the establishment of radiation protection standards. However, the scientific basis for linearity has been brought into question, particularly due to the concerns about induced radiation resistance as it pertains to oxidative stress. Specifically, we investigated the observation that tumor hypoxia is associated with malignant progression, increased metastases, chemo- and radioresistance and poor prognosis. Experiments were conducted with non-malignant 3T3/NIH cells and normal human lung fibroblasts (NHLF) that were subjected to ?-irradiation under the levels of oxygen resembling those in growing tumors, and related our data to the concentrations of dissolved oxygen (DO), which is a better indicator of the amounts of residual oxygen inside the cells cultured in the hypoxic or anoxic atmosphere. We found that at DO levels about 0.5 mg/L cells subjected to both short-term (17 hours) and prolonged (48-72 hours) hypoxia continued to proliferate, and that apoptotic events were decreased at the early hours of hypoxic treatment. We showed that the short-term hypoxia up-regulated p53-binding protein 1 (53BP1) and resulted in facilitated 53BP1 nuclear foci formation and disappearance, thus indicating the higher efficiency of DNA double strand breaks repair processes. The latter was confirmed by the lower micronuclei incidence in irradiated hypoxic cells.

  4. Nonenzymatic Role for WRN in Preserving Nascent DNA Strands after Replication Stress

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

    Su, Fengtao; Mukherjee, Shibani; Yang, Yanyong; Mori, Eiichiro; Bhattacharya, Souparno; Kobayashi, Junya; Yannone, Steven  M.; Chen, David  J.; Asaithamby, Aroumougame

    2014-11-20

    WRN, the protein defective in Werner syndrome (WS), is a multifunctional nuclease involved in DNA damage repair, replication, and genome stability maintenance. It was assumed that the nuclease activities of WRN were critical for these functions. Here, we report a nonenzymatic role for WRN in preserving nascent DNA strands following replication stress. We found that lack of WRN led to shortening of nascent DNA strands after replication stress. Furthermore, we discovered that the exonuclease activity of MRE11 was responsible for the shortening of newly replicated DNA in the absence of WRN. Mechanistically, the N-terminal FHA domain of NBS1 recruits WRNmore » to replication-associated DNA double-stranded breaks to stabilize Rad51 and to limit the nuclease activity of its C-terminal binding partner MRE11. Thus, this previously unrecognized nonenzymatic function of WRN in the stabilization of nascent DNA strands sheds light on the molecular reason for the origin of genome instability in WS individuals.« less

  5. Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec.

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

    1-20, 2006 | Department of Energy Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Docket No. EO-05-01. Regarding the planned line outage, scheduled for Feb. 20 through Mar. 6, I am requesting that the residents near the plant be moved for the duration of the outage to protect their health. Emailed Comments of Elizabeth Chimento RE: Pepco Scheduled Line Repair Dec.

  6. BREAKING BOND

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

    BOE Reserve Class No 2001 reserves 0.1 - 10 MBOE 10.1 - 100 MBOE 100.1 - 1,000 MBOE 1,000.1 - 10,000 MBOE 10,000.1 - 100,000 MBOE > 100,000 MBOE Basin Outline ID The mapped oil and gas field boundary outlines were created by the Reserves and Production Division, Office of Oil and Gas, Energy Information Administration pursuant to studies required by Section 604 of the Energy Policy and Conservation Act Amendments of 2000 (P.L. 106-469). The boundaries are not informed by subsurface structural

  7. In situ repair of a failed compression fitting

    DOE Patents [OSTI]

    Wolbert, R.R.; Jandrasits, W.G.

    1985-08-05

    A method and apparatus for the in situ repair of a failed compression fitting is provided. Initially, a portion of a guide tube is inserted coaxially in the bore of the compression fitting and locked therein. A close fit dethreading device is then coaxially mounted on the guide tube to cut the threads from the fitting. Thereafter, the dethreading device and guide tube are removed and a new fitting is inserted onto the dethreaded fitting with the body of the new fitting overlaying the dethreaded portion. Finally, the main body of the new fitting is welded to the main body of the old fitting whereby a new threaded portion of the replacement fitting is precisely coaxial with the old threaded portion. If needed, a bushing is located on the dethreaded portion which is sized to fit snugly between the dethreaded portion and the new fitting. Preferably, the dethreading device includes a cutting tool which is moved incrementally in a radial direction whereby the threads are cut from the threaded portion of the failed fitting in increments.

  8. In situ repair of a failed compression fitting

    DOE Patents [OSTI]

    Wolbert, Ronald R.; Jandrasits, Walter G.

    1986-01-01

    A method and apparatus for the in situ repair of a failed compression fitg is provided. Initially, a portion of a guide tube is inserted coaxially in the bore of the compression fitting and locked therein. A close fit dethreading device is then coaxially mounted on the guide tube to cut the threads from the fitting. Thereafter, the dethreading device and guide tube are removed and a new fitting is inserted onto the dethreaded fitting with the body of the new fitting overlaying the dethreaded portion. Finally, the main body of the new fitting is welded to the main body of the old fitting whereby a new threaded portion of the replacement fitting is precisely coaxial with the old threaded portion. If needed, a bushing is located on the dethreaded portion which is sized to fit snugly between the dethreaded portion and the new fitting. Preferably, the dethreading device includes a cutting tool which is moved incrementally in a radial direction whereby the threads are cut from the threaded portion of the failed fitting in increments.

  9. Tiny Terminators: New Micro-Robots Assemble, Repair Themselves and Are Surprisingly Strong

    Broader source: Energy.gov [DOE]

    Tiny robots that can assemble and repair themselves? Watch a video of Argonne National Laboratory's micro-robots that easily perform tasks that can challenge other robots, including moving objects that are larger than themselves.

  10. Inducible error-prone repair in B. subtilis. Final report, September 1, 1979-June 30, 1981

    SciTech Connect (OSTI)

    Yasbin, R. E.

    1981-06-01

    The research performed under this contract has been concentrated on the relationship between inducible DNA repair systems, mutagenesis and the competent state in the gram positive bacterium Bacillus subtilis. The following results have been obtained from this research: (1) competent Bacillus subtilis cells have been developed into a sensitive tester system for carcinogens; (2) competent B. subtilis cells have an efficient excision-repair system, however, this system will not function on bacteriophage DNA taken into the cell via the process of transfection; (3) DNA polymerase III is essential in the mechanism of the process of W-reactivation; (4) B. subtilis strains cured of their defective prophages have been isolated and are now being developed for gene cloning systems; (5) protoplasts of B. subtilis have been shown capable of acquiring DNA repair enzymes (i.e., enzyme therapy); and (6) a plasmid was characterized which enhanced inducible error-prone repair in a gram positive organism.

  11. Unmanned deepwater-line repair system passes full-scale trials

    SciTech Connect (OSTI)

    Venzi, S.; Vienna, A. )

    1993-09-06

    The first ever full-scale tests of an unmanned, deepwater-pipeline repair system were successfully conducted last year off the coast of Italy. The Italian gas-transmission company SNAM tested a submersible automatic system (SAS) sealine repair system at a depth of 600 m. The modular SAS allows sealines to be repaired by installation of the Nuovo Pignone mechanical connector. The system's trials simulated complete repair intervention on the 20-in. Trans mediterranean pipeline and provided unprecedented experience to SNAM and to the other involved in this project. The paper discusses the origin of the idea for the SAS, the design of the system, construction and testing, the first sea trials, final deep sea trials, and future developments.

  12. Community-Minded Interns at Savannah River Site Help Area Residents in Need with Home Repairs

    Broader source: Energy.gov [DOE]

    AIKEN, S.C. – More than two dozen college interns who worked at the Savannah River Site (SRS) this summer joined other volunteers and headed into area neighborhoods to help people in need with home repairs.

  13. Review of Maintenance and Repair Times for Components in Technological Facilities

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2012-11-01

    This report is a compilation of some unique component repair time data and it also presents citations of more extensive reports where lists of repair times can be found. This collection of information should support analysts who seek to quantify maintainability and availability of high technology and nuclear energy production systems. While there are newer sources of repair time information, most, if not all, of the newer sources are proprietary and cannot be shared. This report offers data that, while older, is openly accessible and can serve as reasonable estimates of repair times, at least for initial studies. Some times were found for maintenance times in radiation environments, and some guidance for multiplicative factors to use to account for work in contamination areas.

  14. Vacuum Bellows, Vacuum Piping, Cryogenic Break, and Copper Joint Failure Rate Estimates for ITER Design Use

    SciTech Connect (OSTI)

    L. C. Cadwallader

    2010-06-01

    The ITER international project design teams are working to produce an engineering design in preparation for construction of the International Thermonuclear Experimental Reactor (ITER) tokamak. During the course of this work, questions have arisen in regard to safety barriers and equipment reliability as important facets of system design. The vacuum system designers have asked several questions about the reliability of vacuum bellows and vacuum piping. The vessel design team has asked about the reliability of electrical breaks and copper-copper joints used in cryogenic piping. Research into operating experiences of similar equipment has been performed to determine representative failure rates for these components. The following chapters give the research results and the findings for vacuum system bellows, power plant stainless steel piping (amended to represent vacuum system piping), cryogenic system electrical insulating breaks, and copper joints.

  15. RADIAL DEPENDENCE OF THE FREQUENCY BREAK BETWEEN FLUID AND KINETIC SCALES IN THE SOLAR WIND FLUCTUATIONS

    SciTech Connect (OSTI)

    Bruno, R.; Trenchi, L.

    2014-06-01

    We investigate the radial dependence of the spectral break separating the inertial from the dissipation range in power density spectra of interplanetary magnetic field fluctuations, between 0.42 and 5.3 AU, during radial alignments between MESSENGER and WIND for the inner heliosphere and between WIND and ULYSSES for the outer heliosphere. We found that the spectral break moves to higher and higher frequencies as the heliocentric distance decreases. The radial dependence of the corresponding wavenumber is of the kind κ {sub b} ∼ R {sup –1.08}, in good agreement with that of the wavenumber derived from the linear resonance condition for proton cyclotron damping. These results support conclusions from previous studies which suggest that a cyclotron-resonant dissipation mechanism must participate in the spectral cascade together with other possible kinetic noncyclotron-resonant mechanisms.

  16. Breaking of relativistically intense longitudinal space charge waves: A description using Dawson sheet model

    SciTech Connect (OSTI)

    Sengupta, Sudip, E-mail: sudip@ipr.res.in [Institute for Plasma Research, Bhat , Gandhinagar - 382428 (India)

    2014-02-11

    Spatio-temporal evolution of relativistically intense longitudinal space charge waves in a cold homogeneous plasma is studied analytically as well as numerically, as an initial value problem, using Dawson sheet model. It is found that, except for very special initial conditions which generates the well known longitudinal Akhiezer-Polovin mode, for all other initial conditions, the waves break through a novel mechanism called phase mixing at an amplitude well below the Akhiezer-Polovin limit. An immediate consequence of this is, that Akhiezer-Polovin waves break when subjected to arbitrarily small longitudinal perturbations. We demonstrate this by performing extensive numerical simulations. This result may be of direct relevance to ultrashort, ultraintense laser/beam pulse-plasma interaction experiments where relativistically intense waves are routinely excited.

  17. The response of plasma density to breaking inertial gravity wave in the lower regions of ionosphere

    SciTech Connect (OSTI)

    Tang, Wenbo Mahalov, Alex

    2014-04-15

    We present a three-dimensional numerical study for the E and lower F region ionosphere coupled with the neutral atmosphere dynamics. This model is developed based on a previous ionospheric model that examines the transport patterns of plasma density given a prescribed neutral atmospheric flow. Inclusion of neutral dynamics in the model allows us to examine the charge-neutral interactions over the full evolution cycle of an inertial gravity wave when the background flow spins up from rest, saturates and eventually breaks. Using Lagrangian analyses, we show the mixing patterns of the ionospheric responses and the formation of ionospheric layers. The corresponding plasma density in this flow develops complex wave structures and small-scale patches during the gravity wave breaking event.

  18. Reconstitution of the cellular response to DNA damage in vitro using damage-activated extracts from mammalian cells

    SciTech Connect (OSTI)

    Roper, Katherine; Coverley, Dawn

    2012-03-10

    In proliferating mammalian cells, DNA damage is detected by sensors that elicit a cellular response which arrests the cell cycle and repairs the damage. As part of the DNA damage response, DNA replication is inhibited and, within seconds, histone H2AX is phosphorylated. Here we describe a cell-free system that reconstitutes the cellular response to DNA double strand breaks using damage-activated cell extracts and naieve nuclei. Using this system the effect of damage signalling on nuclei that do not contain DNA lesions can be studied, thereby uncoupling signalling and repair. Soluble extracts from G1/S phase cells that were treated with etoposide before isolation, or pre-incubated with nuclei from etoposide-treated cells during an in vitro activation reaction, restrain both initiation and elongation of DNA replication in naieve nuclei. At the same time, H2AX is phosphorylated in naieve nuclei in a manner that is dependent upon the phosphatidylinositol 3-kinase-like protein kinases. Notably, phosphorylated H2AX is not focal in naieve nuclei, but is evident throughout the nucleus suggesting that in the absence of DNA lesions the signal is not amplified such that discrete foci can be detected. This system offers a novel screening approach for inhibitors of DNA damage response kinases, which we demonstrate using the inhibitors wortmannin and LY294002. -- Highlights: Black-Right-Pointing-Pointer A cell free system that reconstitutes the response to DNA damage in the absence of DNA lesions. Black-Right-Pointing-Pointer Damage-activated extracts impose the cellular response to DNA damage on naieve nuclei. Black-Right-Pointing-Pointer PIKK-dependent response impacts positively and negatively on two separate fluorescent outputs. Black-Right-Pointing-Pointer Can be used to screen for inhibitors that impact on the response to damage but not on DNA repair. Black-Right-Pointing-Pointer LY294002 and wortmannin demonstrate the system's potential as a pathway focused screening

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

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

    Y-12 National Security Complex Largest Federally Owned ... Largest Federally Owned Wind Farm Breaks Ground at U.S. Weapons Facility Posted: August 13, 2013 - 12:01pm 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

  20. Cynthia Phillips, ground-breaking expert in plasma waves &amp; Princeton

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

    graduate school lecturer, dies after long illness | Princeton Plasma Physics Lab Cynthia Phillips, ground-breaking expert in plasma waves & Princeton graduate school lecturer, dies after long illness By Jeanne Jackson DeVoe September 4, 2015 Tweet Widget Google Plus One Share on Facebook Cynthia Philips (Photo by Elle Starkman ) Cynthia Philips Cynthia K. Phillips, a physicist at PPPL for 32 years and a former lecturer in Princeton's graduate program in plasma physics, died on Sept. 1

  1. Method to repair localized amplitude defects in a EUV lithography mask blank

    DOE Patents [OSTI]

    Stearns, Daniel G.; Sweeney, Donald W.; Mirkarimi, Paul B.; Chapman, Henry N.

    2005-11-22

    A method and apparatus are provided for the repair of an amplitude defect in a multilayer coating. A significant number of layers underneath the amplitude defect are undamaged. The repair technique restores the local reflectivity of the coating by physically removing the defect and leaving a wide, shallow crater that exposes the underlying intact layers. The particle, pit or scratch is first removed the remaining damaged region is etched away without disturbing the intact underlying layers.

  2. RESTORING A DAMAGED 16-YEAR -OLD INSULATING POLYMER CONCRETE DIKE OVERLAY: REPAIR MATERIALS AND TECHNOLOGIES.

    SciTech Connect (OSTI)

    SUGAMA,T.

    2007-01-01

    The objective of this program was to design and formulate organic polymer-based material systems suitable for repairing and restoring the overlay panels of insulating lightweight polymer concrete (ILPC) from the concrete floor and slope wall of a dike at KeySpan liquefied natural gas (LNG) facility in Greenpoint, Brooklyn, NY, just over sixteen years ago. It also included undertaking a small-scale field demonstration to ensure that the commercial repairing technologies were applicable to the designed and formulated materials.

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

    SciTech Connect (OSTI)

    Gallardo, S.; Querol, A.; Verdu, G.

    2012-07-01

    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)

  4. Dynamical instability induced by the zero mode under symmetry breaking external perturbation

    SciTech Connect (OSTI)

    Takahashi, J. Nakamura, Y. Yamanaka, Y.

    2014-08-15

    A complex eigenvalue in the Bogoliubov–de Gennes equations for a stationary Bose-Einstein condensate in the ultracold atomic system indicates the dynamical instability of the system. We also have the modes with zero eigenvalues for the condensate, called the zero modes, which originate from the spontaneous breakdown of symmetries. Although the zero modes are suppressed in many theoretical analyses, we take account of them in this paper and argue that a zero mode can change into one with a pure imaginary eigenvalue by applying a symmetry breaking external perturbation potential. This emergence of a pure imaginary mode adds a new type of scenario of dynamical instability to that characterized by the complex eigenvalue of the usual excitation modes. For illustration, we deal with two one-dimensional homogeneous Bose–Einstein condensate systems with a single dark soliton under a respective perturbation potential, breaking the invariance under translation, to derive pure imaginary modes. - Highlights: • Zero modes are important but ignored in many theories for the cold atomic system. • We discuss the zero mode under symmetry breaking potential in this system. • We consider the zero mode of translational invariance for a single dark soliton. • We show that it turns into an anomalous or pure imaginary mode.

  5. Selective breaking of bonds in water with intense, 2-cycle, infrared laser pulses

    SciTech Connect (OSTI)

    Mathur, D. Dharmadhikari, A. K.; Dota, K.; Dey, D.; Tiwari, A. K.; Dharmadhikari, J. A.; De, S.; Vasa, P.

    2015-12-28

    One of the holy grails of contemporary science has been to establish the possibility of preferentially breaking one of several bonds in a molecule. For instance, the two O–H bonds in water are equivalent: given sufficient energy, either one of them is equally likely to break. We report bond-selective molecular fragmentation upon application of intense, 2-cycle pulses of 800 nm laser light: we demonstrate up to three-fold enhancement for preferential bond breaking in isotopically substituted water (HOD). Our experimental observations are rationalized by means of ab initio computations of the potential energy surfaces of HOD, HOD{sup +}, and HOD{sup 2+} and explorations of the dissociation limits resulting from either O–H or O–D bond rupture. The observations we report present a formidable theoretical challenge that need to be taken up in order to gain insights into molecular dynamics, strong field physics, chemical physics, non-adiabatic processes, mass spectrometry, and time-dependent quantum chemistry.

  6. Laser engineered net shaping (LENS) for the repair and modification of NWC metal components.

    SciTech Connect (OSTI)

    Atwood, Clinton J.; Smugeresky, John E. (Sandia National Labs, Livermore,CA); Gill, David Dennis

    2006-11-01

    Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a layer additive manufacturing process that creates fully dense metal components using a laser, metal powder, and a computer solid model. This process has previously been utilized in research settings to create metal components and new material alloys. The ''Qualification of LENS for the Repair and Modification of Metal NWC Components'' project team has completed a Technology Investment project to investigate the use of LENS for repair of high rigor components. The team submitted components from four NWC sites for repair or modification using the LENS process. These components were then evaluated for their compatibility to high rigor weapons applications. The repairs included hole filling, replacement of weld lips, addition of step joints, and repair of surface flaws and gouges. The parts were evaluated for mechanical properties, corrosion resistance, weldability, and hydrogen compatibility. This document is a record of the LENS processing of each of these component types and includes process parameters, build strategies, and lessons learned. Through this project, the LENS process was shown to successfully repair or modify metal NWC components.

  7. Formation and Repair of Tobacco Carcinogen-Derived Bulky DNA Adducts

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

    Hang, Bo

    2010-01-01

    DNA adducts play a central role in chemical carcinogenesis. The analysis of formation and repair of smoking-related DNA adducts remains particularly challenging as both smokers and nonsmokers exposed to smoke are repetitively under attack from complex mixtures of carcinogens such as polycyclic aromatic hydrocarbons and N -nitrosamines. The bulky DNA adducts, which usually have complex structure, are particularly important because of their biological relevance. Several known cellular DNA repair pathways have been known to operate in human cells on specific types of bulky DNA adducts, for example, nucleotide excision repair, base excision repair, and direct reversal involving O 6more » -alkylguanine DNA alkyltransferase or AlkB homologs. Understanding the mechanisms of adduct formation and repair processes is critical for the assessment of cancer risk resulting from exposure to cigarette smoke, and ultimately for developing strategies of cancer prevention. This paper highlights the recent progress made in the areas concerning formation and repair of bulky DNA adducts in the context of tobacco carcinogen-associated genotoxic and carcinogenic effects.« less

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

    SciTech Connect (OSTI)

    Prisecaru, Ilie; Dupleac, Daniel; Ghitescu, Petre; Biro, Lucian

    2006-07-01

    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)

  9. Relocation and repair of the National Geotechnical Centrifuge. Final report

    SciTech Connect (OSTI)

    Cheney, J.A.

    1994-10-01

    In January of 1984, the large geotechnical centrifuge located at NASA Ames Research Center, was in the first stages of operational checkout when the main thrust bearing of the large D.C. drive motor failed. After many months of investigation and proposals for repair of the facility, it became evident that it would be far more advantageous to the engineering community to remove those components of the centrifuge that were undamaged to the Davis campus and replace the drive system completely. The large centrifuge had cost over 2 million dollars to build, and it would have been irresponsible to simply scrap it. Recognizing this fact, funds were solicited and received from various sources, and Beam Engineering Inc. was contracted to design and construct the centrifuge at its new location. The University of California contributed a quarter of a million dollars and Tyndall Air Force Base, through Los Alamos National Laboratory, contributed $140,000. There were funds also contributed by LANL, LLNL, US Navy and NSF. The first stage in the phased development of the newly located centrifuge is nearing completion, which prompts the writing of this report. By the time that this report reaches the reader the first runs of the centrifuge will have been completed. The present report describes the present capability of the centrifuge and the plans for upgrading as time goes on. Several pilot studies were carried out. The experiments involved (1) the effects of nearby explosions on buried thin walled containers and (2) the advection and dispersion of toxic waste water through soils.

  10. Further Evolution of Composite Doubler Aircraft Repairs Through a Focus on Niche Applications

    SciTech Connect (OSTI)

    ROACH,DENNIS P.

    2000-07-15

    The number of commercial airframes exceeding twenty years of service continues to grow. A typical aircraft can experience over 2,000 fatigue cycles (cabin pressurizations) and even greater flight hours in a single year. An unavoidable by-product of aircraft use is that crack and corrosion flaws develop throughout the aircraft's skin and substructure elements. Economic barriers to the purchase of new aircraft have created an aging aircraft fleet and placed even greater demands on efficient and safe repair methods. The use of bonded composite doublers offers the airframe manufacturers and aircraft maintenance facilities a cost effective method to safety extend the lives of their aircraft. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is now possible to bond a single Boron-Epoxy composite doubler to the damaged structure. The FAA's Airworthiness Assurance Center at Sandia National Labs (AANC) is conducting a program with Boeing and Federal Express to validate and introduce composite doubler repair technology to the US commercial aircraft industry. This project focuses on repair of DC-10 structure and builds on the foundation of the successful L-1011 door corner repair that was completed by the AANC, Lockheed-Martin, and Delta Air Lines. The L-1011 composite doubler repair was installed in 1997 and has not developed any flaws in over three years of service, As a follow-on effort, this DC-1O repair program investigated design, analysis, performance (durability, flaw containment, reliability), installation, and nondestructive inspection issues. Current activities are demonstrating regular use of composite doubler repairs on commercial aircraft. The primary goal of this program is to move the technology into niche applications and to streamline the design-to-installation process. Using the data accumulated to date, the team has designed, analyzed, and developed inspection techniques for an array of composite doubler repairs

  11. Development of bonded composite doublers for the repair of oil recovery equipment.

    SciTech Connect (OSTI)

    Roach, David W.; Rackow, Kirk A.

    2005-06-01

    An unavoidable by-product of a metallic structure's use is the appearance of crack and corrosion flaws. Economic barriers to the replacement of these structures have created an aging infrastructure and placed even greater demands on efficient and safe repair methods. In the past decade, an advanced composite repair technology has made great strides in commercial aviation use. Extensive testing and analysis, through joint programs between the Sandia Labs FAA Airworthiness Assurance Center and the aviation industry, have proven that composite materials can be used to repair damaged aluminum structure. Successful pilot programs have produced flight performance history to establish the durability of bonded composite patches as a permanent repair on commercial aircraft structures. With this foundation in place, this effort is adapting bonded composite repair technology to civil structures. The use of bonded composite doublers has the potential to correct the difficulties associated with current repair techniques and the ability to be applied where there are no rehabilitation options. It promises to be cost-effective with minimal disruption to the users of the structure. This report concludes a study into the application of composite patches on thick steel structures typically used in mining operations. Extreme fatigue, temperature, erosive, and corrosive environments induce an array of equipment damage. The current weld repair techniques for these structures provide a fatigue life that is inferior to that of the original plate. Subsequent cracking must be revisited on a regular basis. The use of composite doublers, which do not have brittle fracture problems such as those inherent in welds, can help extend the structure's fatigue life and reduce the equipment downtime. Two of the main issues for adapting aircraft composite repairs to civil applications are developing an installation technique for carbon steel and accommodating large repairs on extremely thick structures

  12. INTERNAL REPAIR OF GAS PIPLINES SURVEY OF OPERATOR EXPERIENCE AND INDUSTRY NEEDS REPORT

    SciTech Connect (OSTI)

    Ian D. Harris

    2003-09-01

    A repair method that can be applied from the inside of a gas transmission pipeline (i.e., a trenchless repair) is an attractive alternative to conventional repair methods since the need to excavate the pipeline is precluded. This is particularly true for pipelines in environmentally sensitive and highly populated areas. The objectives of the project are to evaluate, develop, demonstrate, and validate internal repair methods for pipelines; develop a functional specification for an internal pipeline repair system; and prepare a recommended practice for internal repair of pipelines. The purpose of this survey is to better understand the needs and performance requirements of the natural gas transmission industry regarding internal repair. A total of fifty-six surveys were sent to pipeline operators. A total of twenty completed surveys were returned, representing a 36% response rate, which is considered very good given the fact that tailored surveys are known in the marketing industry to seldom attract more than a 10% response rate. The twenty survey responses produced the following principal conclusions: (1) Use of internal weld repair is most attractive for river crossings, under other bodies of water (e.g., lakes and swamps) in difficult soil conditions, under highways, under congested intersections, and under railway crossings. All these areas tend to be very difficult and very costly if, and where, conventional excavated repairs may be currently used. (2) Internal pipe repair offers a strong potential advantage to the high cost of horizontal direct drilling (HDD) when a new bore must be created to solve a leak or other problem in a water/river crossing. (3) The typical travel distances required can be divided into three distinct groups: up to 305 m (1,000 ft.); between 305 m and 610 m (1,000 ft. and 2,000 ft.); and beyond 914 m (3,000 ft.). In concept, these groups require pig-based systems; despooled umbilical systems could be considered for the first two groups

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

    SciTech Connect (OSTI)

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

    2011-07-01

    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).

  14. Focus Series: The Greater Cincinnati Energy Alliance (GCEA) Equipment Lease Program Breaks Down Barriers for Cincinnati Contractors

    Broader source: Energy.gov [DOE]

    Focus Series: The Greater Cincinnati Energy Alliance (GCEA) Equipment Lease Program Breaks Down Barriers for Cincinnati Contractors, a publication of the U.S. Department of Energy's Better Buildings Neighborhood Program.

  15. DNA repair decline during mouse spermiogenesis results in the accumulation of heritable DNA damage

    SciTech Connect (OSTI)

    Marchetti, Francesco; Marchetti, Francesco; Wryobek, Andrew J

    2008-02-21

    The post-meiotic phase of mouse spermatogenesis (spermiogenesis) is very sensitive to the genomic effects of environmental mutagens because as male germ cells form mature sperm they progressively lose the ability to repair DNA damage. We hypothesized that repeated exposures to mutagens during this repair-deficient phase result in the accumulation of heritable genomic damage in mouse sperm that leads to chromosomal aberrations in zygotes after fertilization. We used a combination of single or fractionated exposures to diepoxybutane (DEB), a component of tobacco smoke, to investigate how differential DNA repair efficiencies during the three weeks of spermiogenesis affected the accumulation of DEB-induced heritable damage in early spermatids (21-15 days before fertilization, dbf), late spermatids (14-8 dbf) and sperm (7- 1 dbf). Analysis of chromosomalaberrations in zygotic metaphases using PAINT/DAPI showed that late spermatids and sperm are unable to repair DEB-induced DNA damage as demonstrated by significant increases (P<0.001) in the frequencies of zygotes with chromosomal aberrations. Comparisons between single and fractionated exposures suggested that the DNA repair-deficient window during late spermiogenesis may be less than two weeks in the mouse and that during this repair-deficient window there is accumulation of DNA damage in sperm. Finally, the dose-response study in sperm indicated a linear response for both single and repeated exposures. These findings show that the differential DNA repair capacity of post-meioitic male germ cells has a major impact on the risk of paternally transmitted heritable damage and suggest that chronic exposures that may occur in the weeks prior to fertilization because of occupational or lifestyle factors (i.e, smoking) can lead to an accumulation of genetic damage in sperm and result in heritable chromosomal aberrations of paternal origin.

  16. DNA Repair Decline During Mouse Spermiogenesis Results in the Accumulation of Heritable DNA Damage

    SciTech Connect (OSTI)

    Marchetti, Francesco; Marchetti, Francesco; Wyrobek, Andrew J.

    2007-12-01

    The post-meiotic phase of mouse spermatogenesis (spermiogenesis) is very sensitive to the genomic effects of environmental mutagens because as male germ cells form mature sperm they progressively lose the ability to repair DNA damage. We hypothesized that repeated exposures to mutagens during this repair-deficient phase result in the accumulation of heritable genomic damage in mouse sperm that leads to chromosomal aberrations in zygotes after fertilization. We used a combination of single or fractionated exposures to diepoxybutane (DEB), a component of tobacco smoke, to investigate how differential DNA repair efficiencies during the three weeks of spermiogenesis affected the accumulation of DEB-induced heritable damage in early spermatids (21-15 days before fertilization, dbf), late spermatids (14-8 dbf) and sperm (7-1 dbf). Analysis of chromosomal aberrations in zygotic metaphases using PAINT/DAPI showed that late spermatids and sperm are unable to repair DEB-induced DNA damage as demonstrated by significant increases (P<0.001) in the frequencies of zygotes with chromosomal aberrations. Comparisons between single and fractionated exposures suggested that the DNA repair-deficient window during late spermiogenesis may be less than two weeks in the mouse and that during this repair-deficient window there is accumulation of DNA damage in sperm. Finally, the dose-response study in sperm indicated a linear response for both single and repeated exposures. These findings show that the differential DNA repair capacity of post-meioitic male germ cells has a major impact on the risk of paternally transmitted heritable damage and suggest that chronic exposures that may occur in the weeks prior to fertilization because of occupational or lifestyle factors (i.e, smoking) can lead to an accumulation of genetic damage in sperm and result in heritable chromosomal aberrations of paternal origin.

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

    SciTech Connect (OSTI)

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

    2011-02-01

    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.

  18. RELAP5/MOD2 assessment, OECD-LOFT small break experiment LP-SB-03

    SciTech Connect (OSTI)

    Guntay, S. )

    1990-04-01

    An analysis of the experimental results and post-test calculations using RELAP5/MOD2 carried out for OECD-LOFT small break experiment LP-SB-3 are presented. Experiment LP-SB-3 was conducted on March 5, 1984 in Loss-of-Fluid Test (LOFT) facility located at the Idaho National Engineering Laboratory (INEL). The experiment simulated a small cold leg break, with concurrent loss of high pressure injection system, and cooldown and recovery by feed and bleed of the steam generator secondary side and accumulator injection, respectively. The analysis was under taken as a part of a program at EIR aimed at developing experience in using the latest generation of best estimate Loss of Coolant Accident (LOCA) analysis computer codes, and to improve understanding of Small Break LOCA transients and as well as a part of a program aimed at assessing the RELAP5/MOD2 code. The latest available version (Cycle 33 to 36.1) of the code was used. The particular test selected for the analysis included several phenomena potentially relevant to any PWR plant operation in Switzerland. This report documents a short post-test analysis of the experiment emphasizing the results of additional analysis performed during the course of this task. RELAP5/MOD2 input model and results of the post-test calculation are documented. Included in the report are the results of a sensitivity analysis which show the predicted thermal-hydraulic response to a different input model. 7 refs., 55 figs., 2 tabs.

  19. Sphericity and symmetry breaking in the formation of Frank–Kasper phases from one component materials

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

    Lee, Sangwoo; Leighton, Chris; Bates, Frank S.

    2014-11-05

    Frank–Kasper phases are tetrahedrally packed structures occurring in numerous materials, from elements to intermetallics to self-assembled soft materials. They exhibit complex manifolds of Wigner–Seitz cells with many-faceted polyhedra, forming an important bridge between the simple close-packed periodic and quasiperiodic crystals. The recent discovery of the Frank–Kasper σ-phase in diblock and tetrablock polymers stimulated the experiments reported here on a poly(isoprene-b-lactide) diblock copolymer melt. Thus, analysis of small-angle X-ray scattering and mechanical spectroscopy exposes an undiscovered competition between the tendency to form self-assembled particles with spherical symmetry, and the necessity to fill space at uniform density within the framework imposed bymore » the lattice. We thus deduce surprising analogies between the symmetry breaking at the body-centered cubic phase to σ-phase transition in diblock copolymers, mediated by exchange of mass, and the symmetry breaking in certain metals and alloys (such as the elements Mn and U), mediated by exchange of charge. Similar connections are made between the role of sphericity in real space for polymer systems, and the role of sphericity in reciprocal space for metallic systems such as intermetallic compounds and alloys. These findings establish new links between disparate materials classes, provide opportunities to improve the understanding of complex crystallization by building on synergies between hard and soft matter, and, perhaps most significantly, challenge the view that the symmetry breaking required to form reduced symmetry structures (possibly even quasiperiodic crystals) requires particles with multiple predetermined shapes and/or sizes.« less

  20. Sphericity and symmetry breaking in the formation of Frank–Kasper phases from one component materials

    SciTech Connect (OSTI)

    Lee, Sangwoo; Leighton, Chris; Bates, Frank S.

    2014-11-05

    Frank–Kasper phases are tetrahedrally packed structures occurring in numerous materials, from elements to intermetallics to self-assembled soft materials. They exhibit complex manifolds of Wigner–Seitz cells with many-faceted polyhedra, forming an important bridge between the simple close-packed periodic and quasiperiodic crystals. The recent discovery of the Frank–Kasper σ-phase in diblock and tetrablock polymers stimulated the experiments reported here on a poly(isoprene-b-lactide) diblock copolymer melt. Thus, analysis of small-angle X-ray scattering and mechanical spectroscopy exposes an undiscovered competition between the tendency to form self-assembled particles with spherical symmetry, and the necessity to fill space at uniform density within the framework imposed by the lattice. We thus deduce surprising analogies between the symmetry breaking at the body-centered cubic phase to σ-phase transition in diblock copolymers, mediated by exchange of mass, and the symmetry breaking in certain metals and alloys (such as the elements Mn and U), mediated by exchange of charge. Similar connections are made between the role of sphericity in real space for polymer systems, and the role of sphericity in reciprocal space for metallic systems such as intermetallic compounds and alloys. These findings establish new links between disparate materials classes, provide opportunities to improve the understanding of complex crystallization by building on synergies between hard and soft matter, and, perhaps most significantly, challenge the view that the symmetry breaking required to form reduced symmetry structures (possibly even quasiperiodic crystals) requires particles with multiple predetermined shapes and/or sizes.

  1. Patient Compliance with Surveillance Following Elective Endovascular Aneurysm Repair

    SciTech Connect (OSTI)

    Godfrey, Anthony D. Morbi, Abigail H. M. Nordon, Ian M.

    2015-10-15

    PurposeIntegral to maintaining good outcomes post-endovascular aneurysm repair (EVAR) is a robust surveillance protocol. A significant proportion of patients fail to comply with surveillance, exposing themselves to complications. We examine EVAR surveillance in Wessex (UK), exploring factors that may predict poor compliance.MethodsRetrospective analysis of 179 consecutive elective EVAR cases [2008–2013] was performed. 167 patients were male, with the age range of 50–95. Surveillance was conducted centrally (tertiary referral trauma centre) and at four spoke units. Surveillance compliance and predictors of non-compliance including age, gender, co-morbid status, residential location and socioeconomic status were analysed for univariate significance.ResultsFifty patients (27.9 %) were non-compliant with surveillance; 14 (8.1 %) had no imaging post-EVAR. At 1 year, 56.1 % (of 123 patients) were compliant. At years 2 and 3, 41.5 and 41.2 % (of 65 and 34 patients, respectively) were compliant. Four years post-EVAR, only one of eight attended surveillance (12.5 %). There were no statistically significant differences in age (p = 0.77), co-morbid status or gender (p = 0.64). Distance to central unit (p = 0.67) and surveillance site (p = 0.56) was non-significant. While there was a trend towards compliance in upper-middle-class socioeconomic groups (ABC1 vs. C1C2D), correlating with >50 % of non-compliant patients living within <10 mile radius of the central unit, overall predictive value was not significant (p = 0.82).ConclusionsCompliance with surveillance post-EVAR is poor. No independent predictor of non-compliance has been confirmed, but socioeconomic status appears to be relevant. There is a worrying drop-off in attendance beyond the first year. This study highlights a problem that needs to be addressed urgently, if we are to maintain good outcomes post-EVAR.

  2. Working report and instruction for repairing of three peaces of wings from a 30 kW Riisagermill

    SciTech Connect (OSTI)

    Ethelfeld, J.; Jensen, F.; Kjoller, J.; Lystrup, A.

    1980-01-01

    This report is made to give the owners of Riisager windmills an instruction to make service and repair of the fiber glass wings.

  3. Large Break LOCA Accident Management Strategies for Accidents With Large Containment Leaks

    SciTech Connect (OSTI)

    Sdouz, Gert

    2006-07-01

    The goal of this work is the investigation of the influence of different accident management strategies on the thermal-hydraulics in the containment during a Large Break Loss of Coolant Accident with a large containment leak from the beginning of the accident. The increasing relevance of terrorism suggests a closer look at this kind of severe accidents. Normally the course of severe accidents and their associated phenomena are investigated with the assumption of an intact containment from the beginning of the accident. This intact containment has the ability to retain a large part of the radioactive inventory. In these cases there is only a release via a very small leakage due to the un-tightness of the containment up to cavity bottom melt through. This paper represents the last part of a comprehensive study on the influence of accident management strategies on the source term of VVER-1000 reactors. Basically two different accident sequences were investigated: the 'Station Blackout'- sequence and the 'Large Break LOCA'. In a first step the source term calculations were performed assuming an intact containment from the beginning of the accident and no accident management action. In a further step the influence of different accident management strategies was studied. The last part of the project was a repetition of the calculations with the assumption of a damaged containment from the beginning of the accident. This paper concentrates on the last step in the case of a Large Break LOCA. To be able to compare the results with calculations performed years ago the calculations were performed using the Source Term Code Package (STCP), hydrogen explosions are not considered. In this study four different scenarios have been investigated. The main parameter was the switch on time of the spray systems. One of the results is the influence of different accident management strategies on the source term. In the comparison with the sequence with intact containment it was

  4. Non-destructive qualification tests for ITER cryogenic axial insulating breaks

    SciTech Connect (OSTI)

    Kosek, Jacek; Lopez, Roberto; Tommasini, Davide; Rodriguez-Mateos, Felix

    2014-01-29

    In the ITER superconducting magnets the dielectric separation between the CICC (Cable-In-Conduit Conductors) and the helium supply pipes is made through the so-called insulating breaks (IB). These devices shall provide the required dielectric insulation at a 30 kV level under different types of stresses and constraints: thermal, mechanical, dielectric and ionizing radiations. As part of the R and D program, the ITER Organization launched contracts with industrial companies aimed at the qualification of the manufacturing techniques. After reviewing the main functional aspects, this paper describes and discusses the protocol established for non-destructive qualification tests of the prototypes.

  5. Performance improvements of symmetry-breaking reflector structures in nonimaging devices

    DOE Patents [OSTI]

    Winston, Roland

    2004-01-13

    A structure and method for providing a broken symmetry reflector structure for a solar concentrator device. The component of the optical direction vector along the symmetry axis is conserved for all rays propagated through a translationally symmetric optical device. This quantity, referred to as the translational skew invariant, is conserved in rotationally symmetric optical systems. Performance limits for translationally symmetric nonimaging optical devices are derived from the distributions of the translational skew invariant for the optical source and for the target to which flux is to be transferred. A numerically optimized non-tracking solar concentrator utilizing symmetry-breaking reflector structures can overcome the performance limits associated with translational symmetry.

  6. SPACE code simulation of cold leg small break LOCA in the ATLAS integral test

    SciTech Connect (OSTI)

    Kim, B. J.; Kim, H. T.; Kim, J.; Kim, K. D.

    2012-07-01

    SPACE code is a system analysis code for pressurized water reactors. This code uses a two-fluid and three-field model. For a few years, intensive validations have been performed to secure the prediction accuracy of models and correlations for two-phase flow and heat transfer. Recently, the code version 1.0 was released. This study is to see how well SPACE code predicts thermal hydraulic phenomena of an integral effect test. The target experiment is a cold leg small break LOCA in the ATLAS facility, which has the same two-loop features as APR1400. Predicted parameters were compared with experimental observations. (authors)

  7. A probabilistic method for leak-before-break analysis of CANDU reactor pressure tubes

    SciTech Connect (OSTI)

    Puls, M.P.; Wilkins, B.J.S.; Rigby, G.L.

    1997-04-01

    A probabilistic code for the prediction of the cumulative probability of pressure tube ruptures in CANDU type reactors is described. Ruptures are assumed to result from the axial growth by delayed hydride cracking. The BLOOM code models the major phenomena that affect crack length and critical crack length during the reactor sequence of events following the first indications of leakage. BLOOM can be used to develop unit-specific estimates of the actual probability of pressure rupture in operating CANDU reactors and supplement the existing leak before break analysis.

  8. TACIS 91: Application of leak-before-break concept in VVER 440-230

    SciTech Connect (OSTI)

    Bartholome, G.; Faidy, C.; Franco, C.

    1997-04-01

    The applicability of the leak-before-break (LBB) concept for primary piping in the first generation of WWER type plants in Russia is investigated. The procedures for LBB behavior used in France and Germany are applied, and the evaluation is discussed within the framework of the European Technical Assistance for the Community of Independent States (TACIS) project. Emphasis is placed on experimental validation of national and international engineering practice for evaluating and optimizing existing installations. Design criteria of WWER plants are compared to western standard design.

  9. Technology Solutions Case Study: Capillary Break Beneath a Slab: Polyethylene Sheeting over Aggregate, Southwestern Pennsylvania

    SciTech Connect (OSTI)

    2014-07-01

    In this project, Building America team IBACOS worked with a builder of single- and multifamily homes in southwestern Pennsylvania (climate zone 5) to understand its methods of successfully using polyethylene sheeting over aggregate as a capillary break beneath the slab in new construction. This builder’s homes vary in terms of whether they have crawlspaces or basements. However, in both cases, the strategy protects the home from water intrusion via capillary action (e.g., water wicking into cracks and spaces in the slab), thereby helping to preserve the durability of the home.

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

    SciTech Connect (OSTI)

    Alvaro Calle Cordon,Manuel Pavon Valderrama,Enrique Ruiz Arriola

    2012-02-01

    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.

  11. HANFORD SITE LOW EXPOSURE PIPELINE REPAIR USING A NON-METALLIC COMPOSITE SYSTEM

    SciTech Connect (OSTI)

    HUTH RJ

    2009-11-12

    At the Department of Energy, Richland Operations (DOE-RL) Hanford site in eastern Washington, a 350 mm (14 inch) diameter high density polyethylene (HDPE) pump recirculation pipeline failed at a bonded joint adjacent to a radiologically and chemically contaminated groundwater storage basin. The responsible DOE-RL contractor, CH2MHill Plateau Remediation Company, applied a fiberglass reinforced plastic (composite) field repair system to the failed joint. The system was devised specifically for the HDPE pipe repair at the Hanford site, and had not been used on this type of plastic piping previously. This paper introduces the pipe failure scenario, describes the options considered for repair and discusses the ultimate resolution of the problem. The failed pipeline was successfully returned to service with minimal impact on waste water treatment plant operating capacity. Additionally, radiological and chemical exposures to facility personnel were maintained as low as reasonably achievable (ALARA). The repair is considered a success for the near term, and future monitoring will prove whether the repair can be considered for long term service and as a viable alternative for similar piping failures at the Hanford site.

  12. Fabrication Flaw Density and Distribution in the Repairs of Reactor Pressure Vessels

    SciTech Connect (OSTI)

    Schuster, George J.; Doctor, Steven R.; Simonen, Fredric A.

    2006-02-15

    The Pacific Northwest National Laboratory (PNNL) is developing a generalized flaw size and density distribution for the population of U.S. reactor pressure vessels (RPVs). The purpose of the generalized flaw distribution is to predict vessel specific flaw rates for use in probabilistic fracture mechanics calculations that estimate vessel failure probability. Considerable progress has been made on the construction of an engineering data base of fabrication flaws in U.S. nuclear RPVs. The fabrication processes and product forms used to construct U.S. RPVs are represented in the data base. A validation methodology has been developed for characterizing the flaws for size, shape, orientation, and composition. The relevance of construction records has been established for describing fabrication processes and product forms. The fabrication flaws were detected in material removed from cancelled nuclear power plants using high sensitivity nondestructive ultrasonic testing, and validated by other nondestructive evaluation (NDE) techniques, and complemented by destructive testing. This paper describes research that has generated data on welding flaws, which indicated that the largest flaws occur in weld repairs. Recent research results confirm that repair flaws are complex in composition and may include cracks on the repair ends. Section III of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code for nuclear power plant components requires radiographic examinations (RT) of welds and requires repairs for RT indications that exceed code acceptable sizes. PNNL has previously obtained the complete construction records for two RPVs. Analysis of these records show a significant change in repair frequency.

  13. A survey of repair practices for nuclear power plant containment metallic pressure boundaries

    SciTech Connect (OSTI)

    Oland, C.B.; Naus, D.J.

    1998-05-01

    The Nuclear Regulatory Commission has initiated a program at the Oak Ridge National Laboratory to provide assistance in their assessment of the effects of potential degradation on the structural integrity and leaktightness of metal containment vessels and steel liners of concrete containments in nuclear power plants. One of the program objectives is to identify repair practices for restoring metallic containment pressure boundary components that have been damaged or degraded in service. This report presents issues associated with inservice condition assessments and continued service evaluations and identifies the rules and requirements for the repair and replacement of nonconforming containment pressure boundary components by welding or metal removal. Discussion topics include base and welding materials, welding procedure and performance qualifications, inspection techniques, testing methods, acceptance criteria, and documentation requirements necessary for making acceptable repairs and replacements so that the plant can be returned to a safe operating condition.

  14. Automatic coke oven heating control system at Burns Harbor for normal and repair operation

    SciTech Connect (OSTI)

    Battle, E.T.; Chen, K.L.

    1997-12-31

    An automatic heating control system for coke oven batteries was developed in 1985 for the Burns Harbor No. 1 battery and reported in the 1989 Ironmaking Conference Proceedings. The original system was designed to maintain a target coke temperature at a given production level under normal operating conditions. Since 1989, enhancements have been made to this control system so that it can also control the battery heating when the battery is under repair. The new control system has improved heating control capability because it adjusts the heat input to the battery in response to anticipated changes in the production schedule. During a recent repair of this 82 oven battery, the pushing schedule changed from 102 ovens/day to 88 ovens/day, then back to 102 ovens/day, then to 107 ovens/day. During this repair, the control system was able to maintain the coke temperature average standard deviation at 44 F, with a maximum 75 F.

  15. Alternatives Analysis Amchitka Island Mud Pit Cap Repair, Amchitka, Alaska January 2016

    SciTech Connect (OSTI)

    Darr, Paul S.

    2016-01-01

    The U.S. Department of Energy (DOE) Office of Legacy Management (LM) manages the Nevada Offsites program, which includes a series of reclaimed drilling mud impoundments on Amchitka Island, Alaska (Figure 1). Navarro Research and Engineering, Inc. is the Legacy Management Support contractor (the Contractor) for LM. The Contractor has procured Tetra Tech, Inc. to provide engineering support to the Amchitka mud pit reclamation project. The mud pit caps were damaged during a 7.9-magnitude earthquake that occurred in 2014. The goals of the current project are to investigate conditions at the mud pit impoundments, identify feasible alternatives for repair of the cover systems and the contents, and estimate relative costs of repair alternatives. This report presents descriptions of the sites and past investigations, existing conditions, summaries of various repair/mitigation alternatives, and direct, unburdened, order-of-magnitude (-15% to +50%) associated costs.

  16. Evaluation of bisphenol E cyanate ester for the resin-injection repair of advanced composites

    SciTech Connect (OSTI)

    Wilber Yaote Lio

    2009-12-19

    This thesis is a compilation of a general introduction and literature review that ties together the subsequent chapters which consist of two journal articles that have yet to be submitted for publication. The overall topic relates to the evaluation and application of a new class of cyanate ester resin with unique properties that lend it applicable to use as a resin for injection repair of high glass transition temperature polymer matrix composites. The first article (Chapter 2) details the evaluation and optimization of adhesive properties of this cyanate ester and alumina nanocomposites under different conditions. The second article (Chapter 3) describes the development and evaluation of an injection repair system for repairing delaminations in polymer matrix composites.

  17. WIMP and SIMP dark matter from the spontaneous breaking of a global group

    SciTech Connect (OSTI)

    Bernal, Nicolás; Garcia-Cely, Camilo; Rosenfeld, Rogério

    2015-04-09

    We propose and study a scalar extension of the Standard Model which respects a ℤ{sub 3} symmetry remnant of the spontaneous breaking of a global U(1){sub DM} symmetry. Consequently, this model has a natural dark matter candidate and a Goldstone boson in the physical spectrum. In addition, the Higgs boson properties are changed with respect to the Standard Model due to the mixing with a new particle. We explore regions in the parameter space taking into account bounds from the measured Higgs properties, dark matter direct detection as well as measurements of the effective number of neutrino species before recombination. The dark matter relic density is determined by three classes of processes: the usual self-annihilation, semi-annihilation and purely dark matter 3→2 processes. The latter has been subject of recent interest leading to the so-called ‘Strongly Interacting Massive Particle’ (SIMP) scenario. We show under which conditions our model can lead to a concrete realization of such scenario and study the possibility that the dark matter self-interactions could address the small scale structure problems. In particular, we find that in order for the SIMP scenario to work, the dark matter mass must be in the range 7−115 MeV, with the global symmetry energy breaking scale in the TeV range.

  18. Leak before break evaluation for main steam piping system made of SA106 Gr.C

    SciTech Connect (OSTI)

    Yang, Kyoung Mo; Jee, Kye Kwang; Pyo, Chang Ryul; Ra, In Sik

    1997-04-01

    The basis of the leak before break (LBB) concept is to demonstrate that piping will leak significantly before a double ended guillotine break (DEGB) occurs. This is demonstrated by quantifying and evaluating the leak process and prescribing safe shutdown of the plant on the basis of the monitored leak rate. The application of LBB for power plant design has reduced plant cost while improving plant integrity. Several evaluations employing LBB analysis on system piping based on DEGB design have been completed. However, the application of LBB on main steam (MS) piping, which is LBB applicable piping, has not been performed due to several uncertainties associated with occurrence of steam hammer and dynamic strain aging (DSA). The objective of this paper is to demonstrate the applicability of the LBB design concept to main steam lines manufactured with SA106 Gr.C carbon steel. Based on the material properties, including fracture toughness and tensile properties obtained from the comprehensive material tests for base and weld metals, a parametric study was performed as described in this paper. The PICEP code was used to determine leak size crack (LSC) and the FLET code was used to perform the stability assessment of MS piping. The effects of material properties obtained from tests were evaluated to determine the LBB applicability for the MS piping. It can be shown from this parametric study that the MS piping has a high possibility of design using LBB analysis.

  19. Transition pathways in a many-body system: Application to hydrogen-bond breaking in water

    SciTech Connect (OSTI)

    Csajka, F.S.; Chandler, D.

    1998-07-01

    We apply a stochastic method introduced by Dellago {ital et al.} [J. Chem. Phys. {bold 108}, 1964 (1998)] to sample transition paths in high-dimensional systems. The method connects two endpoint regions (for example a reactant and a product region) by a set of space-time paths. This approach is an importance sampling for rare events that does not require prior knowledge of the location of dynamical bottlenecks. Transition paths are generated with a weight corresponding to a chain of Metropolis Monte Carlo steps. We derive Monte Carlo algorithms and apply the technique to the dynamics of hydrogen-bond breaking in liquid water. We obtain averages in a transition path ensemble for the structure and energy along the trajectory. While characterized by a rate constant, hydrogen-bond breaking in water occurs frequently enough to be studied by standard methods. The process therefore provides a useful test of path sampling methods. The comparison between path sampling and standard Monte Carlo demonstrate the feasibility of transition path sampling for a many-body system with a rough potential energy surface. {copyright} {ital 1998 American Institute of Physics.}

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

    SciTech Connect (OSTI)

    Rhoads, James E.; Malhotra, Sangeeta; Cohen, Seth; Zheng Zhenya; Stern, Daniel; Dickinson, Mark; Pirzkal, Norbert; Grogin, Norman; Koekemoer, Anton; Peth, Michael A.; Spinrad, Hyron; Reddy, Naveen; Hathi, Nimish; Budavari, Tamas; Ferreras, Ignacio; Gardner, Jonathan P.; Gronwall, Caryl; Haiman, Zoltan; Kuemmel, Martin; Meurer, Gerhardt; and others

    2013-08-10

    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.

  1. Remote reactor repair: GTA (gas tungsten Arc) weld cracking caused by entrapped helium

    SciTech Connect (OSTI)

    Kanne, W.R. Jr.

    1988-01-01

    A repair patch was welded to the wall of a nuclear reactor tank using remotely controlled thirty-foot long robot arms. Further repair was halted when gas tungsten arc (GTA) welds joining type 304L stainless steel patches to the 304 stainless steel wall developed toe cracks in the heat-affected zone (HAZ). The role of helium in cracking was investigated using material with entrapped helium from tritium decay. As a result of this investigation, and of an extensive array of diagnostic tests performed on reactor tank wall material, helium embrittlement was shown to be the cause of the toe cracks.

  2. Bosh repairs No. 3 blast furnace, Edgar Thomson Plant Mon Valley Works

    SciTech Connect (OSTI)

    Stoupis, M.G.

    1993-01-01

    The paper describes in detail the steps taken from quenching to dry out of the furnace to repair the bosh area of the No.3 blast furnace. Inspection of the area revealed that there was no brick anywhere in the bosh. Brick in the tuyere breast area had been peeled back to reveal the steel plate, and descaling revealed 14 pipes fully exposed. None were leaking, but one seemed badly deteriorated. Conventional repairs could not take place before the scheduled blow-in. Installation of coolers were instead tried.

  3. AZD5438, an Inhibitor of Cdk1, 2, and 9, Enhances the Radiosensitivity of Non-Small Cell Lung Carcinoma Cells

    SciTech Connect (OSTI)

    Raghavan, Pavithra; Tumati, Vasu; Yu Lan; Chan, Norman; Tomimatsu, Nozomi; Burma, Sandeep; Simmons Comprehensive Cancer Center, Dallas, Texas ; Bristow, Robert G.; Saha, Debabrata; Simmons Comprehensive Cancer Center, Dallas, Texas

    2012-11-15

    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.

  4. Nucleolar exit of RNF8 and BRCA1 in response to DNA damage

    SciTech Connect (OSTI)

    Guerra-Rebollo, Marta; Mateo, Francesca; Franke, Kristin; Huen, Michael S.Y.; Lopitz-Otsoa, Fernando; Rodriguez, Manuel S.; Plans, Vanessa; Thomson, Timothy M.

    2012-11-01

    The induction of DNA double-strand breaks (DSBs) elicits a plethora of responses that redirect many cellular functions to the vital task of repairing the injury, collectively known as the DNA damage response (DDR). We have found that, in the absence of DNA damage, the DSB repair factors RNF8 and BRCA1 are associated with the nucleolus. Shortly after exposure of cells to {gamma}-radiation, RNF8 and BRCA1 translocated from the nucleolus to damage foci, a traffic that was reverted several hours after the damage. RNF8 interacted through its FHA domain with the ribosomal protein RPSA, and knockdown of RPSA caused a depletion of nucleolar RNF8 and BRCA1, suggesting that the interaction of RNF8 with RPSA is critical for the nucleolar localization of these DDR factors. Knockdown of RPSA or RNF8 impaired bulk protein translation, as did {gamma}-irradiation, the latter being partially countered by overexpression of exogenous RNF8. Our results suggest that RNF8 and BRCA1 are anchored to the nucleolus through reversible interactions with RPSA and that, in addition to its known functions in DDR, RNF8 may play a role in protein synthesis, possibly linking the nucleolar exit of this factor to the attenuation of protein synthesis in response to DNA damage. -- Highlights: Black-Right-Pointing-Pointer RNF8 and BRCA1 are associated with the nucleolus of undamaged cells. Black-Right-Pointing-Pointer Upon {gamma}-radiation, RNF8 and BRCA1 are translocated from the nucleolus to damage foci. Black-Right-Pointing-Pointer The ribosomal protein RPSA anchors RNF8 to the nucleolus. Black-Right-Pointing-Pointer RNF8 may play previously unsuspected roles in protein synthesis.

  5. Persistence of gamma-H2AX and 53BP1 foci in proliferating and nonproliferating human mammary epithelial cells after exposure to gamma-rays or iron ions

    SciTech Connect (OSTI)

    Groesser, Torsten; Chang, Hang; Fontenay, Gerald; Chen, James; Costes, Sylvain V.; Barcellos-Hoff, Mary Helen; Parvin, Bahram; Rydberg, Bjorn

    2010-12-22

    To investigate {gamma}-H2AX (phosphorylated histone H2AX) and 53BP1 (tumour protein 53 binding protein No. 1) foci formation and removal in proliferating and non-proliferating human mammary epithelial cells (HMEC) after exposure to sparsely and densely ionizing radiation under different cell culture conditions. HMEC cells were grown either as monolayers (2D) or in extracellular matrix to allow the formation of acinar structures in vitro (3D). Foci numbers were quantified by image analysis at various time points after exposure. Our results reveal that in non-proliferating cells under 2D and 3D cell culture conditions, iron-ion induced {gamma}-H2AX foci were still present at 72 h after exposure, although 53BP1 foci returned to control levels at 48 h. In contrast in proliferating HMEC, both {gamma}-H2AX and 53BP1 foci decreased to control levels during the 24-48 h time interval after irradiation under 2D conditions. Foci numbers decreased faster after {gamma}-ray irradiation and returned to control levels by 12 h regardless of marker, cell proliferation status, and cell culture condition. Conclusions: The disappearance of radiation induced {gamma}-H2AX and 53BP1 foci in HMEC have different dynamics that depend on radiation quality and proliferation status. Notably, the general patterns do not depend on the cell culture condition (2D versus 3D). We speculate that the persistent {gamma}-H2AX foci in iron-ion irradiated non-proliferating cells could be due to limited availability of double strand break (DSB) repair pathways in G0/G1-phase, or that repair of complex DSB requires replication or chromatin remodeling.

  6. Hot repair of ceramic burner on hot blast stoves at USS/Kobe`s {number_sign}3 blast furnace

    SciTech Connect (OSTI)

    Bernarding, T.F.; Chemorov, M.; Shimono, S.; Phillips, G.R.

    1997-12-31

    During the 1992 reline of the No. 3 blast furnace, three new stoves were constructed. The design of the stoves, equipped with internal ceramic burners, was for providing a hot blast temperature of 2,000 F at a wind rate of 140,000 SCFM. After 3 years the performance had deteriorated so the burners were cleaned. When a second cleaning did not improve the performance of No. 3 blast furnace, it was decided to repair the refractory while still hot. The paper describes the hot repair procedures, taking a stove off for repairs, maintenance heat up during repairs, two stove operation, stove commissioning, repair of a ceramic burner, and wet gas prevention.

  7. The non-equilibrium response of a superconductor to pair-breaking radiation measured over a broad frequency band

    SciTech Connect (OSTI)

    Visser, P. J. de; Yates, S. J. C.; Guruswamy, T.; Goldie, D. J.; Withington, S.; Neto, A.; Llombart, N.; Baryshev, A. M.; Klapwijk, T. M.; Baselmans, J. J. A.

    2015-06-22

    We have measured the absorption of terahertz radiation in a BCS superconductor over a broad range of frequencies from 200 GHz to 1.1 THz, using a broadband antenna-lens system and a tantalum microwave resonator. From low frequencies, the response of the resonator rises rapidly to a maximum at the gap edge of the superconductor. From there on, the response drops to half the maximum response at twice the pair-breaking energy. At higher frequencies, the response rises again due to trapping of pair-breaking phonons in the superconductor. In practice, this is a measurement of the frequency dependence of the quasiparticle creation efficiency due to pair-breaking in a superconductor. The efficiency, calculated from the different non-equilibrium quasiparticle distribution functions at each frequency, is in agreement with the measurements.

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

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi; Bulanov, Stepan S.; Schroeder, Carl B.; Esarey, Eric; Califano, Francesco; Pegoraro, Francesco

    2012-11-15

    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.

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

    SciTech Connect (OSTI)

    Marchetti, Francesco; Wyrobek, Andrew J.

    2009-01-18

    Exposure to ionizing radiation and other environmental agents can affect the genomic integrity of germ cells and induce adverse health effects in the progeny. Efficient DNA repair during gametogenesis and the early embryonic cycles after fertilization is critical for preventing transmission of DNA damage to the progeny and relies on maternal factors stored in the egg before fertilization. The ability of the maternal repair machinery to repair DNA damage in both parental genomes in the fertilizing egg is especially crucial for the fertilizing male genome that has not experienced a DNA repair-competent cellular environment for several weeks prior to fertilization. During the DNA repair-deficient period of spermatogenesis, DNA lesions may accumulate in sperm and be carried into the egg where, if not properly repaired, could result in the formation of heritable chromosomal aberrations or mutations and associated birth defects. Studies with female mice deficient in specific DNA repair genes have shown that: (i) cell cycle checkpoints are activated in the fertilized egg by DNA damage carried by the sperm; and (ii) the maternal genotype plays a major role in determining the efficiency of repairing genomic lesions in the fertilizing sperm and directly affect the risk for abnormal reproductive outcomes. There is also growing evidence that implicates DNA damage carried by the fertilizing gamete as a mediator of postfertilization processes that contribute to genomic instability in subsequent generations. Transgenerational genomic instability most likely involves epigenetic mechanisms or error-prone DNA repair processes in the early embryo. Maternal and embryonic DNA repair processes during the early phases of mammalian embryonic development can have far reaching consequences for the genomic integrity and health of subsequent generations.

  10. Small-break loss-of-coolant accidents in the updated PIUS 600 advanced reactor design

    SciTech Connect (OSTI)

    Boyack, B.E.; Steiner, J.L.; Harmony, S.C.

    1995-09-01

    The PIUS advanced reactor is a 640-MWe pressurized water reactor developed by Asea Brown Boveri (ABB). A unique feature of the PIUS concept is the absence of mechanical control and shutdown rods. Reactivity is normally controlled by coolant boron concentration and the temperature of the moderator coolant. ABB submitted the PIUS design to the US Nuclear Regulatory Commission (NRC) for preapplication review, and Los Alamos supported the NRC`s review effort. Baseline analyses of small-break initiators at two locations were performed with the system neutronic and thermal-hydraulic analysis code TRAC-PF1/MOD2. In addition, sensitivity studies were performed to explore the robustness of the PIUS concept to severe off-normal conditions having a very low probability of occurrence.

  11. Isospin-symmetry-breaking effects in A∼70 nuclei within beyond-mean-field approach

    SciTech Connect (OSTI)

    Petrovici, A.; Andrei, O.

    2015-02-24

    Particular isospin-symmetry-breaking probes including Coulomb energy differences (CED), mirror energy differences (MED), and triplet energy differences (TED) manifest anomalies in the A∼70 isovector triplets of nuclei. The structure of proton-rich nuclei in the A∼70 mass region suggests shape coexistence and competition between pairing correlations in different channels. Recent results concerning the interplay between isospin-mixing and shape-coexistence effects on exotic phenomena in A∼70 nuclei obtained within the beyond-mean-field complex Excited Vampir variational model with symmetry projection before variation using a realistic effective interaction in a relatively large model space are presented. Excited Vampir predictions concerning the Gamow-Teller β decay to the odd-odd N=Z {sup 66}As and {sup 70}Br nuclei correlated with the pair structure analysis in the T=1 and T=0 channel of the involved wave functions are discussed.

  12. Spontaneous symmetry breaking in cosmos: the hybrid symmetron as a dark energy switching device

    SciTech Connect (OSTI)

    Bamba, K.; Nojiri, S.; Gannouji, R.; Kamijo, M.; Sami, M. E-mail: gannouji@rs.kagu.tus.ac.jp E-mail: nojiri@phys.nagoya-u.ac.jp

    2013-07-01

    We consider symmetron model in a generalized background with a hope to make it compatible with dark energy. We observe a ''no go'' theorem at least in case of a conformal coupling. Being convinced of symmetron incapability to be dark energy, we try to retain its role for spontaneous symmetry breaking and assign the role of dark energy either to standard quintessence or F(R) theory which are switched on by symmetron field in the symmetry broken phase. The scenario reduces to standard Einstein gravity in the high density region. After the phase transition generated by symmetron field, either the F(R) gravity or the standard quintessence are induced in the low density region. we demonstrate that local gravity constraints and other requirements are satisfied although the model could generate the late-time acceleration of Universe.

  13. Break-up of Pt catalyst surfaces by high CO coverage

    SciTech Connect (OSTI)

    Tao, Feng; Dag, Sefa; Wang, Lin-Wang; Liu, Zhi; Butcher, Derek; Bluhm, Henrik; Salmeron, Miquel; Somorjai, Gabor

    2009-09-16

    Stepped Platinum surfaces were found to undergo extensive and reversible restructuring when exposed to CO at pressures above 0.1 Torr. This radically new and previously unknown restructuring phenomenon, has important implications for Pt based catalytic reactions. Novel Scanning Tunneling Microscopy and Photoelectron Spectroscopy techniques operating under gaseous environments near ambient pressure and temperature revealed that as the CO surface coverage approaches 100percent, the originally flat terraces of stepped Pt crystals break up into nanometer size clusters. At room temperature the crystal surface reverts to its initial flat morphology after pumping away the gas phase CO. Density Functional Theory energy calculations provide a rationale for the observations whereby the creation of increased concentrations of low coordination Pt sites at the edges of the formed nanoclusters relieves the strong CO-CO repulsion in the highly compressed adsorbate film.

  14. Direct method gas-phase oxygen abundances of four Lyman break analogs

    SciTech Connect (OSTI)

    Brown, Jonathan S.; Croxall, Kevin V.; Pogge, Richard W.

    2014-09-10

    We measure the gas-phase oxygen abundances in four Lyman break analogs using auroral emission lines to derive direct abundances. The direct method oxygen abundances of these objects are generally consistent with the empirically derived strong-line method values, confirming that these objects are low oxygen abundance outliers from the mass-metallicity (MZ) relation defined by star forming Sloan Digital Sky Survey galaxies. We find slightly anomalous excitation conditions (Wolf-Rayet features) that could potentially bias the empirical estimates toward high values if caution is not exercised in the selection of the strong-line calibration. The high rate of star formation and low oxygen abundance of these objects is consistent with the predictions of the fundamental metallicity relation, in which the infall of relatively unenriched gas simultaneously triggers an episode of star formation and dilutes the interstellar medium of the host galaxy.

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

    SciTech Connect (OSTI)

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

    2012-10-15

    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.

  16. SPIN-PRECESSION: BREAKING THE BLACK HOLE-NEUTRON STAR DEGENERACY

    SciTech Connect (OSTI)

    Chatziioannou, Katerina; Cornish, Neil; Klein, Antoine; Yunes, Nicols

    2015-01-01

    Mergers of compact stellar remnants are prime targets for the LIGO/Virgo gravitational wave detectors. The gravitational wave signals from these merger events can be used to study the mass and spin distribution of stellar remnants, and provide information about black hole horizons and the material properties of neutron stars. However, it has been suggested that degeneracies in the way that the star's mass and spin are imprinted in the waveforms may make it impossible to distinguish between black holes and neutron stars. Here we show that the precession of the orbital plane due to spin-orbit coupling breaks the mass-spin degeneracy, and allows us to distinguish between standard neutron stars and alternative possibilities, such as black holes or exotic neutron stars with large masses and spins.

  17. Specialist meeting on leak before break in reactor piping and vessels

    SciTech Connect (OSTI)

    Bartholome, G.; Bazant, E.; Wellein, R.

    1997-04-01

    A series of research projects sponsored by the Federal Minister for Education, Science, Research and Technology, Bonn are summarized and compared to utility, manufacturer, and vendor tests. The purpose of the evaluation was to experimentally verify Leak-before-Break behavior, confirm the postulation of fracture preclusion for piping (straight pipe, bends and branches), and quantify the safety margin against massive failure. The results are applicable to safety assessment of ferritic and austenitic piping in primary and secondary nuclear power plant circuits. Moreover, because of the wide range of the test parameters, they are also important for the design and assessment of piping in other technical plant. The test results provide justification for ruling out catastrophic fractures, even on pipes of dimensions corresponding to those of a main coolant pipe of a pressurized water reactor plant on the basis of a mechanical deterministic safety analysis in correspondence with the Basis Safety Concept (Principle of Fracture Exclusion).

  18. Practical applications of the R6 leak-before-break procedure

    SciTech Connect (OSTI)

    Bouchard, P.J.

    1997-04-01

    A forthcoming revision to the R6 Leak-before-Break Assessment Procedure is briefly described. Practical application of the LbB concepts to safety-critical nuclear plant is illustrated by examples covering both low temperature and high temperature (>450{degrees}C) operating regimes. The examples highlight a number of issues which can make the development of a satisfactory LbB case problematic: for example, coping with highly loaded components, methodology assumptions and the definition of margins, the effect of crack closure owing to weld residual stresses, complex thermal stress fields or primary bending fields, the treatment of locally high stresses at crack intersections with free surfaces, the choice of local limit load solution when predicting ligament breakthrough, and the scope of calculations required to support even a simplified LbB case for high temperature steam pipe-work systems.

  19. Time-reversal symmetry breaking and the field theory of quantum chaos

    SciTech Connect (OSTI)

    Simons, B.D. [Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE (United Kingdom)] [Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE (United Kingdom); Agam, O. [NEC Research Institute, 4 Independence Way, Princeton, New Jersey 08540 (United States)] [NEC Research Institute, 4 Independence Way, Princeton, New Jersey 08540 (United States); Andreev, A.V. [Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)] [Institute for Theoretical Physics, University of California, Santa Barbara, California 93106 (United States)

    1997-04-01

    Recent studies have shown that the quantum statistical properties of systems which are chaotic in their classical limit can be expressed in terms of an effective field theory. Within this description, spectral properties are determined by low energy relaxation modes of the classical evolution operator. It is in the interaction of these modes that quantum interference effects are encoded. In this paper we review this general approach and discuss how the theory is modified to account for time-reversal symmetry breaking. To keep our discussion general, we will also briefly describe how the theory is modified by the presence of an additional discrete symmetry such as inversion. Throughout, parallels are drawn between quantum chaotic systems and the properties of weakly disordered conductors. {copyright} {ital 1997 American Institute of Physics.}

  20. Fuel-rod response during the large-break LOCA Test LOC-6. [PWR

    SciTech Connect (OSTI)

    Vinjamuri, K.; Cook, B.A.; Hobbins, R.R.

    1981-01-01

    The large break Loss of Coolant Accident (LOCA) Test LOC-6 was conducted in the Power Burst Facility (PBF) at the Idaho National Engineering Laboratory by EG and G Idaho, Inc. The objectives of the PBF LOCA tests are to obtain in-pile cladding ballooning data under blowdown and reflood conditions and assess how well out-of-pile ballooning data represent in-pile fuel rod behavior. The primary objective of the LOC-6 test was to determine the effects of internal rod pressures and prior irradiation on the deformation behavior of fuel rods that reached cladding temperatures high in the alpha phase of zircaloy. Test LOC-6 was conducted with four rods of PWR 15 x 15 design with the exception of fuel stack length (89 cm) and enrichment (12.5 W% /sup 235/U). Each rod was surrounded by an individual flow shroud.

  1. Multilayer sulfur-resistant composite metal membranes and methods of making and repairing the same

    DOE Patents [OSTI]

    Way, J. Douglas; Hatlevik, Oyvind

    2014-07-15

    The invention relates to thin, hydrogen-permeable, sulfur-resistant membranes formed from multi-layers of palladium or palladium-alloy coatings on porous, ceramic or metal supports, methods of making these membranes, methods of repairing layers of these membranes and devices that incorporate these membranes.

  2. The behavior of ANGRA 2 nuclear power plant core for a small break LOCA simulated with RELAP5 code

    SciTech Connect (OSTI)

    Sabundjian, Gaiane; Andrade, Delvonei A.; Belchior, Antonio Jr.; Silva Rocha, Marcelo da; Conti, Thadeu N.; Torres, Walmir M.; Macedo, Luiz A.; Umbehaun, Pedro E.; Mesquita, Roberto N.; Masotti, Paulo H. F.; Souza Lima, Ana Cecilia de

    2013-05-06

    This work discusses the behavior of Angra 2 nuclear power plant core, for a postulate Loss of Coolant Accident (LOCA) in the primary circuit for Small Break Loss Of Coolant Accident (SBLOCA). A pipe break of the hot leg Emergency Core Cooling System (ECCS) was simulated with RELAP 5 code. The considered rupture area is 380 cm{sup 2}, which represents 100% of the ECCS pipe flow area. Results showed that the cooling is enough to guarantee the integrity of the reactor core.

  3. NREL Scientists and Engineers Recognized for Top Innovations as Lab Celebrates Another Record-Breaking Year of Inventions

    Office of Energy Efficiency and Renewable Energy (EERE)

    During its annual Innovation and Technology Transfer Awards ceremony on May 3, the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) recognized researchers and staff for 169 new innovations, a record-breaking number of scientific and engineering inventions in fiscal year 2015 (FY15)

  4. On the non-existence of a sharp cooling break in gamma-ray burst afterglow spectra

    SciTech Connect (OSTI)

    Uhm, Z. Lucas; Zhang, Bing, E-mail: uhm@physics.unlv.edu, E-mail: zhang@physics.unlv.edu [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)

    2014-01-01

    Although the widely used analytical afterglow model of gamma-ray bursts (GRBs) predicts a sharp cooling break ? {sub c} in its afterglow spectrum, the GRB observations so far rarely show clear evidence for a cooling break in their spectra or a corresponding temporal break in their light curves. Employing a Lagrangian description of the blast wave, we conduct a sophisticated calculation of the afterglow emission. We precisely follow the cooling history of non-thermal electrons accelerated into each Lagrangian shell. We show that a detailed calculation of afterglow spectra does not in fact give rise to a sharp cooling break at ? {sub c}. Instead, it displays a very mild and smooth transition, which occurs gradually over a few orders of magnitude in energy or frequency. The main source of this slow transition is that different mini shells have different evolutionary histories of the comoving magnetic field strength B, so that deriving the current value of ? {sub c} of each mini shell requires an integration of its cooling rate over the time elapsed since its creation. We present the time evolution of optical and X-ray spectral indices to demonstrate the slow transition of spectral regimes and discuss the implications of our result in interpreting GRB afterglow data.

  5. EVIDENCE FOR ELEVATED X-RAY EMISSION IN LOCAL LYMAN BREAK GALAXY ANALOGS

    SciTech Connect (OSTI)

    Basu-Zych, Antara R.; Lehmer, Bret D.; Hornschemeier, Ann E.; Ptak, Andrew F.; Goncalves, Thiago S.; Fragos, Tassos; Heckman, Timothy M.; Overzier, Roderik A.; Schiminovich, David

    2013-09-10

    Our knowledge of how X-ray emission scales with star formation at the earliest times in the universe relies on studies of very distant Lyman break galaxies (LBGs). In this paper, we study the relationship between the 2-10 keV X-ray luminosity (L{sub X}), assumed to originate from X-ray binaries (XRBs), and star formation rate (SFR) in ultraviolet (UV) selected z < 0.1 Lyman break analogs (LBAs). We present Chandra observations for four new Galaxy Evolution Explorer selected LBAs. Including previously studied LBAs, Haro 11 and VV 114, we find that LBAs demonstrate L{sub X}/SFR ratios that are elevated by {approx}1.5{sigma} compared to local galaxies, similar to the ratios found for stacked LBGs in the early universe (z > 2). Unlike some of the composite LBAs studied previously, we show that these LBAs are unlikely to harbor active galactic nuclei, based on their optical and X-ray spectra and the spatial distribution of the X-rays in three spatially extended cases. Instead, we expect that high-mass X-ray binaries (HMXBs) dominate the X-ray emission in these galaxies, based on their high specific SFRs (sSFRs {identical_to} SFR/M{sub *} {>=} 10{sup -9} yr{sup -1}), which suggest the prevalence of young stellar populations. Since both UV-selected populations (LBGs and LBAs) have lower dust attenuations and metallicities compared to similar samples of more typical local galaxies, we investigate the effects of dust extinction and metallicity on the L{sub X}/SFR for the broader population of galaxies with high sSFRs (>10{sup -10} yr{sup -1}). The estimated dust extinctions (corresponding to column densities of N{sub H} < 10{sup 22} cm{sup -2}) are expected to have insignificant effects on observed L{sub X}/SFR ratio for the majority of galaxy samples. We find that the observed relationship between L{sub X}/SFR and metallicity appears consistent with theoretical expectations from XRB population synthesis models. Therefore, we conclude that lower metallicities, related to

  6. A lead-before-break strategy for primary heat transport piping of 500 MWe Indian PHWR

    SciTech Connect (OSTI)

    Chattopadhyay, J.; Dutta, B.K.; Kushwaha, H.S.

    1997-04-01

    Leak-Before-Break (LBB) is being used to design the primary heat transport piping system of 500 MWe Indian Pressurized Heavy Water Reactors (IPHWR). The work is categorized in three directions to demonstrate three levels of safety against sudden catastrophic break. Level 1 is inherent in the design procedure of piping system as per ASME Sec.III with a well defined factor of safety. Level 2 consists of fatigue crack growth study of a postulated part-through flaw at the inside surface of pipes. Level 3 is stability analysis of a postulated leakage size flaw under the maximum credible loading condition. Developmental work related to demonstration of level 2 and level 3 confidence is described in this paper. In a case study on fatigue crack growth on PHT straight pipes for level 2, negligible crack growth is predicted for the life of the reactor. For level 3 analysis, the R6 method has been adopted. A database to evaluate SIF of elbows with throughwall flaws under combined internal pressure and bending moment has been generated to provide one of the inputs for R6 method. The methodology of safety assessment of elbow using R6 method has been demonstrated for a typical pump discharge elbow. In this analysis, limit load of the cracked elbow has been determined by carrying out elasto-plastic finite element analysis. The limit load results compared well with those given by Miller. However, it requires further study to give a general form of limit load solution. On the experimental front, a set of small diameter pipe fracture experiments have been carried out at room temperature and 300{degrees}C. Two important observations of the experiments are - appreciable drop in maximum load at 300{degrees}C in case of SS pipes and out-of-plane crack growth in case of CS pipes. Experimental load deflection curves are finally compared with five J-estimation schemes predictions. A material database of PHT piping materials is also being generated for use in LBB analysis.

  7. Capillary Break Beneath a Slab: Polyethylene Sheeting over Aggregate, Southwestern Pennsylvania (Fact Sheet), Building America Case Study: Technology Solutions for New and Existing Homes, Building Technologies Office (BTO)

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

    Capillary Break Beneath a Slab: Polyethylene Sheeting Over Aggregate Southwestern Pennsylvania PROJECT INFORMATION Project Name: Capillary Break Beneath a Slab: Polyethylene Sheeting Over Aggregate Location: Southwestern PA Type: Residential Partners: Builder is confidential Building America Team: IBACOS, www.ibacos.com Building Component: Foundation, water management Application: New construction; single- and multifamily homes Year Tested: 2013 Applicable Climate Zone(s): All except dry

  8. Repair of localized defects in multilayer-coated reticle blanks for extreme ultraviolet lithography

    DOE Patents [OSTI]

    Stearns, Daniel G.; Sweeney, Donald W.; Mirkarimi, Paul B.

    2004-11-23

    A method is provided for repairing defects in a multilayer coating layered onto a reticle blank used in an extreme ultraviolet lithography (EUVL) system. Using high lateral spatial resolution, energy is deposited in the multilayer coating in the vicinity of the defect. This can be accomplished using a focused electron beam, focused ion beam or a focused electromagnetic radiation. The absorbed energy will cause a structural modification of the film, producing a localized change in the film thickness. The change in film thickness can be controlled with sub-nanometer accuracy by adjusting the energy dose. The lateral spatial resolution of the thickness modification is controlled by the localization of the energy deposition. The film thickness is adjusted locally to correct the perturbation of the reflected field. For example, when the structural modification is a localized film contraction, the repair of a defect consists of flattening a mound or spreading out the sides of a depression.

  9. Subterranean barriers, methods, and apparatuses for forming, inspecting, selectively heating, and repairing same

    DOE Patents [OSTI]

    Nickelson, Reva A.; Sloan, Paul A.; Richardson, John G.; Walsh, Stephanie; Kostelnik, Kevin M.

    2009-04-07

    A subterranean barrier and method for forming same are disclosed, the barrier including a plurality of casing strings wherein at least one casing string of the plurality of casing strings may be affixed to at least another adjacent casing string of the plurality of casing strings through at least one weld, at least one adhesive joint, or both. A method and system for nondestructively inspecting a subterranean barrier is disclosed. For instance, a radiographic signal may be emitted from within a casing string toward an adjacent casing string and the radiographic signal may be detected from within the adjacent casing string. A method of repairing a barrier including removing at least a portion of a casing string and welding a repair element within the casing string is disclosed. A method of selectively heating at least one casing string forming at least a portion of a subterranean barrier is disclosed.

  10. Endovascular Repair of a Ruptured Mycotic Aneurysm of the Common Iliac Artery

    SciTech Connect (OSTI)

    Mofidi, R. Bhat, R.; Nagy, J.; Griffiths, G. D.; Chakraverty, S.

    2007-09-15

    This report describes the case of a ruptured mycotic aneurysm of the left common iliac artery, successfully treated with endovascular stent-grafting. A 64-year-old woman underwent diagnostic coronary angiography complicated by an infected hematoma of the left groin. Seven days later, she developed methicillin-resistant Staphylococcus aureus septicemia and CT scan evidence of perivascular inflammation around the left common iliac artery. This was followed by rupture of a mycotic aneurysm of the left common iliac artery. The lesion was successfully treated with a stent-graft and prolonged antibiotic therapy, and the patient remains free of infection 10 months later. Accumulating evidence suggests that endovascular repair can be used safely for the repair of ruptured infected aneurysms.

  11. Multiphasic survival curves for cells of human tumor cell lines: Induced repair or hypersensitive subpopulation?

    SciTech Connect (OSTI)

    Lambin, P. ||; Fertil, B.; Malaise, E.P.; Joiner, M.C.

    1994-04-01

    Survival of the cells of three human tumor cell lines of differing radiosensitivity was measured after irradiation with single doses of X rays (0.05-5 Gy). At doses below 1 Gy, cells were more radiosensitive than predicted by back-extrapolating the high-dose response. This difference was more marked for cells of the radioresistant cell lines than the radiosensitive cell line so that the {open_quotes}true{close_quotes} initial slopes of the survival curves, at very low doses, were similar for the cells of the three cell lines. This phenomenon could reflect an induced radioresistance so that low doses of X rays are more effective per gray than higher doses, because only at higher doses is there sufficient damage to trigger repair systems or other radioprotective mechanisms which can then act during the time course for repair of DNA injury. 35 refs., 2 figs.

  12. Weld Repair of a Stamped Pressure Vessel in a Radiologically Controlled Zone

    SciTech Connect (OSTI)

    Cannell, Gary L.; Huth, Ralph J.; Hallum, Randall T.

    2013-08-26

    In September 2012 an ASME B&PVC Section VIII stamped pressure vessel located at the DOE Hanford Site Effluent Treatment Facility (ETF) developed a through-wall leak. The vessel, a steam/brine heat exchanger, operated in a radiologically controlled zone (by the CH2MHill PRC or CHPRC), had been in service for approximately 17 years. The heat exchanger is part of a single train evaporator process and its failure caused the entire system to be shut down, significantly impacting facility operations. This paper describes the activities associated with failure characterization, technical decision making/planning for repair by welding, logistical challenges associated with performing work in a radiologically controlled zone, performing the repair, and administrative considerations related to ASME code requirements.

  13. Next Generation of Renewable Electricity Policy: How Rapid Change is Breaking Down Conventional Policy Categories

    SciTech Connect (OSTI)

    Couture, T. D.; Jacobs, D.; Rickerson, W.; Healey, V.

    2015-02-01

    A number of policies have been used historically in order to stimulate the growth of the renewable electricity sector. This paper examines four of these policy instruments: competitive tendering, sometimes called renewable electricity auctions, feed-in tariffs, net metering and net billing, and tradable renewable energy certificates. In recent years, however, a number of changes to both market circumstances and to policy priorities have resulted in numerous policy innovations, including the emergence of policy hybrids. With no common language for these evolving policy mechanisms, policymakers have generally continued to use the same traditional policy labels, occasionally generating confusion as many of these new policies no longer look, or act, like their traditional predecessors. In reviewing these changes, this paper makes two separate but related claims: first, policy labels themselves are breaking down and evolving. As a result, policy comparisons that rely on the conventional labels may no longer be appropriate, or advisable. Second, as policymakers continue to adapt, we are in effect witnessing the emergence of the next generation of renewable electricity policies, a change that could have significant impacts on investment, as well as on market growth in both developed and developing countries.

  14. Measurement of break away yield stress of waxy crude oil and pipeline restart system design

    SciTech Connect (OSTI)

    Williams, T.M.; Hsu, J.J.C.; Patterson, H.L.

    1996-12-31

    Break Away Yield Stress (BAYS) has been measured on waxy crude oil from the South China Sea to help develop appropriate design specifications for the HZ production system. Design of subsea production systems for handling relatively high BAYS crude oils will be discussed. A BAYS measurement system for measuring the live and dead oils at various cooling rates and the effect of cooling rate on BAYS will also be discussed. The measured BAYS of the HZ crude at seabed temperature indicated that if production was interrupted and the crude in the pipeline cooled to seabed temperature, the restart pressure would exceed the pressure rating of the originally planned pipeline. For waxy crude with high yield stress at seawater temperature, the production system must be designed to allow the production to be restarted after unplanned shutdowns. BAYS of the oil can affect the economics of a crude production system. Accurate knowledge of the BAYS will allow optimum spacing of emergency clean out parts or other system modifications that may be considered for an optimum restart system design.

  15. Proceedings of the seminar on leak before break in reactor piping and vessels

    SciTech Connect (OSTI)

    Faidy, C.; Gilles, P.

    1997-04-01

    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.

  16. Inducing chaos by breaking axial symmetry in a black hole magnetosphere

    SciTech Connect (OSTI)

    Kopáček, O.; Karas, V.

    2014-06-01

    While the motion of particles near a rotating, electrically neutral (Kerr), and charged (Kerr-Newman) black hole is always strictly regular, a perturbation in the gravitational or the electromagnetic field generally leads to chaos. The transition from regular to chaotic dynamics is relatively gradual if the system preserves axial symmetry, whereas non-axisymmetry induces chaos more efficiently. Here we study the development of chaos in an oblique (electro-vacuum) magnetosphere of a magnetized black hole. Besides the strong gravity of the massive source represented by the Kerr metric, we consider the presence of a weak, ordered, large-scale magnetic field. An axially symmetric model consisting of a rotating black hole embedded in an aligned magnetic field is generalized by allowing an oblique direction of the field having a general inclination with respect to the rotation axis of the system. The inclination of the field acts as an additional perturbation to the motion of charged particles as it breaks the axial symmetry of the system and cancels the related integral of motion. The axial component of angular momentum is no longer conserved and the resulting system thus has three degrees of freedom. Our primary concern within this contribution is to find out how sensitive the system of bound particles is to the inclination of the field. We employ the method of the maximal Lyapunov exponent to distinguish between regular and chaotic orbits and to quantify their chaoticity. We find that even a small misalignment induces chaotic motion.

  17. LATE-TIME OBSERVATIONS OF GRB 080319B: JET BREAK, HOST GALAXY, AND ACCOMPANYING SUPERNOVA

    SciTech Connect (OSTI)

    Tanvir, N. R.; O'Brien, P. T.; Wiersema, K.; Starling, R. L. C.; Rol, E.; Levan, A. J.; Svensson, K.; Fruchter, A. S.; Granot, J.; Jakobsson, P.; Fynbo, J.; Hjorth, J.; Curran, P. A.; Burrows, D. N.; Genet, F.

    2010-12-10

    The Swift-discovered GRB 080319B was by far the most distant source ever observed at naked-eye brightness, reaching a peak apparent magnitude of 5.3 at a redshift of z = 0.937. We present our late-time optical (Hubble Space Telescope, Gemini, and Very Large Telescope) and X-ray (Chandra) observations, which confirm that an achromatic break occurred in the power-law afterglow light curve at {approx}11 days post-burst. This most likely indicates that the gamma-ray burst (GRB) outflow was collimated, which for a uniform jet would imply a total energy in the jet E{sub jet} {approx}> 10{sup 52} erg. Our observations also show a late-time excess of red light, which is well explained if the GRB was accompanied by a supernova (SN), similar to those seen in some other long-duration GRBs. The latest observations are dominated by light from the host and show that the GRB took place in a faint dwarf galaxy (r(AB) {approx} 27.0, rest frame M{sub B} {approx} -17.2). This galaxy is small even by the standards of other GRB hosts, which is suggestive of a low-metallicity environment. Intriguingly, the properties of this extreme event-a small host and bright SN-are entirely typical of the very low luminosity bursts such as GRB 980425 and GRB 060218.

  18. Symmetry breaking of solitons in two-component Gross-Pitaevskii equations

    SciTech Connect (OSTI)

    Sakaguchi, Hidetsugu; Malomed, Boris A.

    2011-03-15

    We revisit the problem of the spontaneous symmetry breaking (SSB) of solitons in two-component linearly coupled nonlinear systems, adding the nonlinear interaction between the components. With this feature, the system may be realized in new physical settings, in terms of optics and the Bose-Einstein condensate (BEC). SSB bifurcation points are found analytically, for both symmetric and antisymmetric solitons (the symmetry between the two components is meant here). Asymmetric solitons, generated by the bifurcations, are described by means of the variational approximation (VA) and numerical methods, demonstrating good accuracy of the variational results. In the space of the self-phase-modulation (SPM) parameter and soliton's norm, a border separating stable symmetric and asymmetric solitons is identified. The nonlinear coupling may change the character of the SSB bifurcation, from subcritical to supercritical. Collisions between moving asymmetric and symmetric solitons are investigated too. Antisymmetric solitons are destabilized by a supercritical bifurcation, which gives rise to self-confined modes featuring Josephson oscillations, instead of stationary states with broken antisymmetry. An additional instability against delocalized perturbations is also found for the antisymmetric solitons.

  19. PT-symmetric sinusoidal optical lattices at the symmetry-breaking threshold

    SciTech Connect (OSTI)

    Graefe, Eva-Maria [Mathematics Department, Imperial College, London SW7 2BZ (United Kingdom); Jones, H. F. [Physics Department, Imperial College, London SW7 2BZ (United Kingdom)

    2011-07-15

    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.

  20. Study of condensation heat transfer following a main steam line break inside containment

    SciTech Connect (OSTI)

    Cho, J.H.; Elia, F.A. Jr.; Lischer, D.J.

    1995-09-01

    An alternative model for calculating condensation heat transfer following a main stream line break (MSLB) accident is proposed. The proposed model predictions and the current regulatory model predictions are compared to the results of the Carolinas Virginia Tube Reactor (CVTR) test. The very conservative results predicted by the current regulatory model result from: (1) low estimate of the condensation heat transfer coefficient by the Uchida correlation and (2) neglecting the convective contribution to the overall heat transfer. Neglecting the convection overestimates the mass of steam being condensed and does not permit the calculation of additional convective heat transfer resulting from superheated conditions. In this study, the Uchida correlation is used, but correction factors for the effects of convection an superheat are derived. The proposed model uses heat and mass transfer analogy methods to estimate to convective fraction of the total heat transfer and bases the steam removal rate on the condensation heat transfer portion only. The results predicted by the proposed model are shown to be conservative and more accurate than those predicted by the current regulatory model when compared with the results of the CVTR test. Results for typical pressurized water reactors indicate that the proposed model provides a basis for lowering the equipment qualification temperature envelope, particularly at later times following the accident.

  1. Leak before break behaviour of austenitic and ferritic pipes containing circumferential defects

    SciTech Connect (OSTI)

    Stadtmueller, W.; Sturm, D.

    1997-04-01

    Several research projects carried out at MPA Stuttgart to investigate the Leak-before-Break (LBB) behavior of safety relevant pressure bearing components are summarized. Results presented relate to pipes containing circumferential defects subjected to internal pressure and external bending loading. An overview of the experimentally determined results for ferritic components is presented. For components containing postulated or actual defects, the dependence of the critical loading limit on the defect size is shown in the form of LBB curves. These are determined experimentally and/or by calculation for through-wall slits, and represent the boundary curve between leakage and massive fracture. For surface defects and a given bending moment and internal pressure, no fracture will occur if the length at leakage remains smaller than the critical defect length given by the LBB curve for through-wall defects. The predictive capability of engineering calculational methods are presented by way of example. The investigation programs currently underway, testing techniques, and initial results are outlined.

  2. Modulated Tool-Path Chip Breaking For Depleted Uranium Machining Operations

    SciTech Connect (OSTI)

    Barkman, W. E.; Babelay Jr., E. F.; Smith, K. S.; Assaid T. S.; McFarland, J. T.; Tursky, D. A.

    2010-04-15

    Turning operations involving depleted uranium frequently generate long, stringy chips that present a hazard to both the machinist and the machine tool. While a variety of chip-breaking techniques are available, they generally depend on a mechanism that increases the bending of the chip or the introduction of a one dimensional vibration that produces an interrupted cutting pattern. Unfortunately, neither of these approaches is particularly effective when making a 'light depth-of-cut' on a contoured workpiece. The historical solution to this problem has been for the machinist to use long-handled tweezers to 'pull the chip' and try to keep it submerged in the chip pan; however, this approach is not practical for all machining operations. This paper discusses a research project involving the Y-12 National Security Complex and the University of North Carolina at Charlotte in which unique, oscillatory part programs are used to continuously create an interrupted cut that generates pre-defined, user-selectable chip lengths.

  3. Climatology of wave breaking and mixing in the Northern Hemisphere summer stratosphere

    SciTech Connect (OSTI)

    Wagner, R.E.

    1999-07-02

    The cause of large zonal ozone variations observed by POAM II (Polar Ozone and Aerosol Measurement II) in the Northern Hemisphere (NH) summer stratosphere between 55N-65N and 20-30 km is investigated using the United Kingdom Meteorological Office stratospheric data set with time-mean anomalies removed. This study tests the hypothesis from Hoppel et al. 1999 that breaking of westward-propagating planetary waves in the region of maximum ozone variance (RMV) induces substantial meridional transport which is responsible for the observed ozone variance. EP-flux vectors show that wave activity propagates vertically from source regions in the lower midlatitude troposphere into the stratosphere and RMV during the NH summer. In the RMV, EP-flux divergence is clearly nonzero, which means the zonal-mean zonal flow is forced by waves in this region. Close examination of individual zonal wavenumber contributions to the climatological monthly-mean EP-flux divergence shows that wavenumbers 1-5 generally account for over 90% of the forcing of the zonal-mean flow in the RMV from June to August.

  4. Cell-autonomous progeroid changes in conditional mouse models for repair endonuclease XPG deficiency

    SciTech Connect (OSTI)

    Barnhoorn, Sander; Uittenboogaard, Lieneke M.; Jaarsma, Dick; Vermeij, Wilbert P.; Tresini, Maria; Weymaere, Michael; Menoni, Hervé; Brandt, Renata M. C.; de Waard, Monique C.; Botter, Sander M.; Sarker, Altaf H.; Jaspers, Nicolaas G. J.; van der Horst, Gijsbertus T. J.; Cooper, Priscilla K.; Hoeijmakers, Jan H. J.; van der Pluijm, Ingrid; Niedernhofer, Laura J.

    2014-10-09

    As part of the Nucleotide Excision Repair (NER) process, the endonuclease XPG is involved in repair of helix-distorting DNA lesions, but the protein has also been implicated in several other DNA repair systems, complicating genotype-phenotype relationship in XPG patients. Defects in XPG can cause either the cancer-prone condition xeroderma pigmentosum (XP) alone, or XP combined with the severe neurodevelopmental disorder Cockayne Syndrome (CS), or the infantile lethal cerebro-oculo-facio-skeletal (COFS) syndrome, characterized by dramatic growth failure, progressive neurodevelopmental abnormalities and greatly reduced life expectancy. Here, we present a novel (conditional) Xpg-/- mouse model which—in a C57BL6/FVB F1 hybrid genetic background—displays many progeroid features, including cessation of growth, loss of subcutaneous fat, kyphosis, osteoporosis, retinal photoreceptor loss, liver aging, extensive neurodegeneration, and a short lifespan of 4–5 months. We show that deletion of XPG specifically in the liver reproduces the progeroid features in the liver, yet abolishes the effect on growth or lifespan. In addition, specific XPG deletion in neurons and glia of the forebrain creates a progressive neurodegenerative phenotype that shows many characteristics of human XPG deficiency. Our findings therefore exclude that both the liver as well as the neurological phenotype are a secondary consequence of derailment in other cell types, organs or tissues (e.g. vascular abnormalities) and support a cell-autonomous origin caused by the DNA repair defect itself. In addition they allow the dissection of the complex aging process in tissue- and cell-type-specific components. Moreover, our data highlight the critical importance of genetic background in mouse aging studies, establish the Xpg-/- mouse as a valid model for the severe form of human XPG patients and segmental accelerated aging, and strengthen the link between DNA damage and aging.

  5. Cell-autonomous progeroid changes in conditional mouse models for repair endonuclease XPG deficiency

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

    Barnhoorn, Sander; Uittenboogaard, Lieneke M.; Jaarsma, Dick; Vermeij, Wilbert P.; Tresini, Maria; Weymaere, Michael; Menoni, Hervé; Brandt, Renata M. C.; de Waard, Monique C.; Botter, Sander M.; et al

    2014-10-09

    As part of the Nucleotide Excision Repair (NER) process, the endonuclease XPG is involved in repair of helix-distorting DNA lesions, but the protein has also been implicated in several other DNA repair systems, complicating genotype-phenotype relationship in XPG patients. Defects in XPG can cause either the cancer-prone condition xeroderma pigmentosum (XP) alone, or XP combined with the severe neurodevelopmental disorder Cockayne Syndrome (CS), or the infantile lethal cerebro-oculo-facio-skeletal (COFS) syndrome, characterized by dramatic growth failure, progressive neurodevelopmental abnormalities and greatly reduced life expectancy. Here, we present a novel (conditional) Xpg-/- mouse model which—in a C57BL6/FVB F1 hybrid genetic background—displays manymore » progeroid features, including cessation of growth, loss of subcutaneous fat, kyphosis, osteoporosis, retinal photoreceptor loss, liver aging, extensive neurodegeneration, and a short lifespan of 4–5 months. We show that deletion of XPG specifically in the liver reproduces the progeroid features in the liver, yet abolishes the effect on growth or lifespan. In addition, specific XPG deletion in neurons and glia of the forebrain creates a progressive neurodegenerative phenotype that shows many characteristics of human XPG deficiency. Our findings therefore exclude that both the liver as well as the neurological phenotype are a secondary consequence of derailment in other cell types, organs or tissues (e.g. vascular abnormalities) and support a cell-autonomous origin caused by the DNA repair defect itself. In addition they allow the dissection of the complex aging process in tissue- and cell-type-specific components. Moreover, our data highlight the critical importance of genetic background in mouse aging studies, establish the Xpg-/- mouse as a valid model for the severe form of human XPG patients and segmental accelerated aging, and strengthen the link between DNA damage and aging.« less

  6. Quality Improvement Guidelines for Imaging Detection and Treatment of Endoleaks following Endovascular Aneurysm Repair (EVAR)

    SciTech Connect (OSTI)

    Rand, T.; Uberoi, R.; Cil, B.; Munneke, G.; Tsetis, D.

    2013-02-15

    Major concerns after aortic aneurysm repair are caused by the presence of endoleaks, which are defined as persistent perigraft flow within the aortic aneurysm sac. Diagnosis of endoleaks can be performed with various imaging modalities, and indications for treatment are based on further subclassifications. Early detection and correct classification of endoleaks are crucial for planning patient management. The vast majority of endoleaks can be treated successfully by interventional means. Guidelines for Imaging Detection and Treatment of endoleaks are described in this article.

  7. Analysis and testing of the DIII-D ohmic heating coil lead repair clamp

    SciTech Connect (OSTI)

    Reis, E.E.; Anderson, P.M.; Chin, E.; Robinson, J.I.

    1997-11-01

    DIII-D has been operating for the last year with limited volt-second capabilities due to structural failure of a conductor lead to one of the ohmic heating (OH) solenoids. The conductor failure was due to poor epoxy impregnation of the overwrap of the lead pack, resulting in copper fatigue and a water leak. A number of structural analyses were performed to assist in determining the failure scenario and to evaluate various repair options. A fatigue stress analysis of the leads with a failed epoxy overwrap indicated crack initiation after 1,000 cycles at the maximum operating conditions. The failure occurred in a very inaccessible area which restricted design repair options to concepts which could be implemented remotely. Several design options were considered for repairing the lead so that it can sustain the loads for 7.5 Vs conditions at full toroidal field. A clamp, along with preloaded banding straps and shim bags, provides a system that guarantees that the stress at the crack location is always compressive and prevents further crack growth in the conductor. Due to the limited space available for the repair, it was necessary to design the clamp system to operate at the material yield stress. The primary components of the clamp system were verified by load tests prior to installation. The main body of the clamp contains a load cell and potentiometer for monitoring the load-deflection characteristics of the clamp and conductors during plasma operation. Strain gages provides redundant instrumentation. If required, the preload on the conductors can be increased remotely by a special wrench attached to the clamp assembly.

  8. Laser-activated nano-biomaterials for tissue repair and controlled drug release

    SciTech Connect (OSTI)

    Matteini, P; Ratto, F; Rossi, F; Pini, R

    2014-07-31

    We present recent achievements of minimally invasive welding of biological tissue and controlled drug release based on laser-activated nano-biomaterials. In particular, we consider new advancements in the biomedical application of near-IR absorbing gold nano-chromophores as an original solution for the photothermal repair of surgical incisions and as nanotriggers of controlled drug release from hybrid biopolymer scaffolds. (laser biophotonics)

  9. To: Mansueti, Lawrence Subject: RE: Pepco Scheduled Line Repair Dec. 1-20, 2006

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

    From: ecchimento@comcast.net [mailto:ecchimento@comcast.net] Sent: Monday, January 29, 2007 6:28 PM To: Mansueti, Lawrence Subject: RE: Pepco Scheduled Line Repair Dec. 1-20, 2006 Larry, Regarding the planned line outage, scheduled for Feb. 20 through Mar. 6, I am requesting that the residents near the plant be moved for the duration of the outage to protect their health. Would you include this comment also in the ongoing recorded discussion? Thank you. Elizabeth -----Original Message-----

  10. ASTRID sodium cooled fast reactor: Program for improving in service inspection and repair

    SciTech Connect (OSTI)

    Jadot, F.; De Dinechin, G.; Augem, J. M.; Sibilo, J.

    2011-07-01

    In the frame of the CEA, EDF, AREVA coordinated research program for the development of Generation IV sodium-cooled fast reactors (SFR), the ASTRID project was launched in 2010. For the future prototype, the improvement of in-service inspection and repair (ISI and R) capabilities was identified as a major issue. Following the pluri-annual SFR research program, the ISI and R main R and D axes remain: i) improvement of the primary system conceptual design, ii) development of measurement and inspection techniques (continuous monitoring instrumentation and periodic inspection tools), iii) accessibility and associated robotics, and iv) development and validation of repair processes. Associated ISI and R needs are being defined through an iterative method between designers and instrumentation specialists: adaptation of the Design to ISI and R requirements, fission chamber development, validation of the ultrasonic and chemical transducers, of ultrasonic non destructive simulation, of acoustic surveillance, of laser repair intervention processes, of connected robotic equipment. Moreover, CEA, as leader of the ASTRID Project, is willing to find new contributors, partners or suppliers, in order to get innovative, diversified, exhaustive and efficient solutions. (authors)

  11. Relationship of DNA repair processes to mutagenesis and carcinogenesis in mammalian cells. Progress report, August 1, 1977-October 31, 1980

    SciTech Connect (OSTI)

    Evans, H.H.

    1980-10-01

    The objective of this research is to determine the role of DNA repair in mutagenesis and carcinogenesis in mammalian cells. More specifically, mutant strains will be selected which are deficient in various DNA repair pathways. These strains will be studied with regard to (1) the nature of the defect in repair, and (2) the mutability and transformability of the defective cells by various agents as compared to the wild type parental cells. The results to date include progress in the following areas: (1) determination of optimum conditions for growth and maintenance of cells and for quantitative measurement of various cellular parameters; (2) investigation of the effect of holding mutagenized cells for various periods in a density inhibited state on survival and on mutation and transformation frequencies; (3) examination of the repair capabilities of BHK cells, as compared to repair-proficient and repair-deficient human cells and excision-deficient mouse cells, as measured by the reactivation of Herpes simplex virus (HSV) treated with radiation and ethylmethane sulfonate (EMS); (4) initiation of host cell reactivation viral sucide enrichment and screening of survivors of the enrichment for sensitivity to ionizing radiation; and (5) investigation of the toxicity, mutagenicity, and carcinogenicity of various metabolites of 4-nitroquinoline-1-oxide (4-NQO). (ERB)

  12. LENS repair and modification of metal NW components:materials and applications guide.

    SciTech Connect (OSTI)

    Smugeresky, John E. (Sandia National Laboratories, Livermore, CA); Gill, David Dennis; Oberhaus, Jason (BWXT Y-12); Adams, Thad; VanCamp, Chad

    2006-11-01

    Laser Engineered Net Shaping{trademark} (LENS{reg_sign}) is a unique, layer additive, metal manufacturing technique that offers the ability to create fully dense metal features and components directly from a computer solid model. LENS offers opportunities to repair and modify components by adding features to existing geometry, refilling holes, repairing weld lips, and many other potential applications. The material deposited has good mechanical properties with strengths typically slightly higher that wrought material due to grain refinement from a quickly cooling weld pool. The result is a material with properties similar to cold worked material, but without the loss in ductility traditionally seen with such treatments. Furthermore, 304L LENS material exhibits good corrosion resistance and hydrogen compatibility. This report gives a background of the LENS process including materials analysis addressing the requirements of a number of different applications. Suggestions are given to aid both the product engineer and the process engineer in the successful utilization of LENS for their applications. The results of testing on interface strength, machinability, weldability, corrosion resistance, geometric effects, heat treatment, and repair strategy testing are all included. Finally, the qualification of the LENS process is briefly discussed to give the user confidence in selecting LENS as the process of choice for high rigor applications. The testing showed LENS components to have capability in repair/modification applications requiring complex castings (W80-3 D-Bottle bracket), thin wall parts requiring metal to be rebuilt onto the part (W87 Firing Set Housing and Y-12 Test Rings), the filling of counterbores for use in reservoir reclamation welding (SRNL hydrogen compatibility study) and the repair of surface defects on pressure vessels (SRNL gas bottle repair). The material is machinable, as testing has shown that LENS deposited material machines similar to that of

  13. Statistical recoupling: A new way to break the link between electric-utility sales and revenues

    SciTech Connect (OSTI)

    Hirst, E.

    1993-09-01

    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.

  14. Heat generation above break-even from laser-induced fusion in ultra-dense deuterium

    SciTech Connect (OSTI)

    Holmlid, Leif

    2015-08-15

    Previous results from laser-induced processes in ultra-dense deuterium D(0) give conclusive evidence for ejection of neutral massive particles with energy >10 MeV u{sup −1}. Such particles can only be formed from nuclear processes like nuclear fusion at the low laser intensity used. Heat generation is of interest for future fusion energy applications and has now been measured by a small copper (Cu) cylinder surrounding the laser target. The temperature rise of the Cu cylinder is measured with an NTC resistor during around 5000 laser shots per measured point. No heating in the apparatus or the gas feed is normally used. The fusion process is suboptimal relative to previously published studies by a factor of around 10. The small neutral particles H{sub N}(0) of ultra-dense hydrogen (size of a few pm) escape with a substantial fraction of the energy. Heat loss to the D{sub 2} gas (at <1 mbar pressure) is measured and compensated for under various conditions. Heat release of a few W is observed, at up to 50% higher energy than the total laser input thus a gain of 1.5. This is uniquely high for the use of deuterium as fusion fuel. With a slightly different setup, a thermal gain of 2 is reached, thus clearly above break-even for all neutronicity values possible. Also including the large kinetic energy which is directly measured for MeV particles leaving through a small opening gives a gain of 2.3. Taking into account the lower efficiency now due to the suboptimal fusion process, previous studies indicate a gain of at least 20 during long periods.

  15. Additional requirements for leak-before-break application to primary coolant piping in Belgium

    SciTech Connect (OSTI)

    Roussel, G.

    1997-04-01

    Leak-Before-Break (LBB) technology has not been applied in the first design of the seven Pressurized Water Reactors the Belgian utility is currently operating. The design basis of these plants required to consider the dynamic effects associated with the ruptures to be postulated in the high energy piping. The application of the LBB technology to the existing plants has been recently approved by the Belgian Safety Authorities but with a limitation to the primary coolant loop. LBB analysis has been initiated for the Doel 3 and Tihange 2 plants to allow the withdrawal of some of the reactor coolant pump snubbers at both plants and not reinstall some of the restraints after steam generator replacement at Doel 3. LBB analysis was also found beneficial to demonstrate the acceptability of the primary components and piping to the new conditions resulting from power uprating and stretch-out operation. LBB analysis has been subsequently performed on the primary coolant loop of the Tihange I plant and is currently being performed for the Doel 4 plant. Application of the LBB to the primary coolant loop is based in Belgium on the U.S. Nuclear Regulatory Commission requirements. However the Belgian Safety Authorities required some additional analyses and put some restrictions on the benefits of the LBB analysis to maintain the global safety of the plant at a sufficient level. This paper develops the main steps of the safety evaluation performed by the Belgian Safety Authorities for accepting the application of the LBB technology to existing plants and summarizes the requirements asked for in addition to the U.S. Nuclear Regulatory Commission rules.

  16. Spontaneous breaking of scale invariance in a D = 3 U(N ) model with Chern-Simons gauge fields

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

    Bardeen, William A.; Moshe, Moshe

    2014-06-18

    We study spontaneous breaking of scale invariance in the large N limit of three dimensional U(N )κ Chern-Simons theories coupled to a scalar field in the fundamental representation. When a λ6 ( ؆ · Ø)3 self interaction term is added to the action we find a massive phase at a certain critical value for a combination of the λ(6) and ’t Hooft’s λ = N/κ couplings. This model attracted recent attention since at finite κ it contains a singlet sector which is conjectured to be dual to Vasiliev’s higher spin gravity on AdS4. Our paper concentrates on the massive phasemore » of the 3d boundary theory. We discuss the advantage of introducing masses in the boundary theory through spontaneous breaking of scale invariance.« less

  17. Impact of the control rod consumption on the reactivity control of a SFR break-even core

    SciTech Connect (OSTI)

    Blanchet, D.; Fontaine, B.

    2012-07-01

    Current design studies on Sodium Fast Reactor (SFR) differ from those performed in the past by the fact that design criteria are now those of the Generation IV reactors. In order to improve their safety, reactors with break-even cores are preferred because they minimize the needs in terms of reactivity control and limit the consequences of control rod withdrawal. Furthermore, as the reactivity control needs are low, break-even core enables the use of absorbing materials with reduced efficiency (natural boron, hafnium...). Nevertheless, the use of control rods with few absorbing materials may present the disadvantage of a non-negligible ({approx}10%) loss of efficiency due to their consumption under irradiation. This paper presents a methodology to calculate accurately and analyze this consumption. (authors)

  18. Spontaneous breaking of scale invariance in a D = 3 U(N ) model with Chern-Simons gauge fields

    SciTech Connect (OSTI)

    Bardeen, William A.; Moshe, Moshe

    2014-06-18

    We study spontaneous breaking of scale invariance in the large N limit of three dimensional U(N )κ Chern-Simons theories coupled to a scalar field in the fundamental representation. When a λ6 ( Ø· Ø)3 self interaction term is added to the action we find a massive phase at a certain critical value for a combination of the λ(6) and ’t Hooft’s λ = N/κ couplings. This model attracted recent attention since at finite κ it contains a singlet sector which is conjectured to be dual to Vasiliev’s higher spin gravity on AdS4. Our paper concentrates on the massive phase of the 3d boundary theory. We discuss the advantage of introducing masses in the boundary theory through spontaneous breaking of scale invariance.

  19. GAMMA-RAY BURST AFTERGLOW LIGHT CURVES FROM A LORENTZ-BOOSTED SIMULATION FRAME AND THE SHAPE OF THE JET BREAK

    SciTech Connect (OSTI)

    Van Eerten, Hendrik; MacFadyen, Andrew

    2013-04-20

    The early stages of decelerating gamma-ray burst (GRB) afterglow jets have been notoriously difficult to resolve numerically using two-dimensional hydrodynamical simulations even at very high resolution, due to the extreme thinness of the blast wave and high outflow Lorentz factors. However, these resolution issues can be avoided by performing the simulations in a boosted frame, which makes it possible to calculate afterglow light curves from numerically computed flows in sufficient detail to accurately quantify the shape of the jet break and the post-break steepening of the light curve. Here, we study afterglow jet breaks for jets with opening angles of 0.05, 0.1, and 0.2 radians decelerating in a surrounding medium of constant density, observed at various angles ranging from on-axis to the edge of the jet. A single set of scale-invariant functions describing the time evolution of afterglow synchrotron spectral break frequencies and peak flux, depending only on jet opening angle and observer angle, are all that is needed to reconstruct light curves for arbitrary explosion energy, circumburst density and synchrotron particle distribution power law slope p. These functions are presented in the paper. Their time evolutions change directly following the jet break, although an earlier reported temporary post-break steepening of the cooling break is found to have been resolution-induced. We compare synthetic light curves to fit functions using sharp power law breaks as well as smooth power law transitions. We confirm our earlier finding that the measured jet break time is very sensitive to the angle of the observer and can be postponed significantly. We find that the difference in temporal indices across the jet break is larger than theoretically anticipated and is about -(0.5 + 0.5p) below the cooling break and about -(0.25 + 0.5p) above the cooling break, both leading to post-break slopes of roughly about 0.25 - 1.3p, although different observer angles, jet opening

  20. The Impact of RELAP5 Pipe Break Flow Rates Associated With Reverse Flow Limiter Removal for Steam Generator Replacement

    SciTech Connect (OSTI)

    Dong Zheng; Jarvis, Julie M.; Vieira, Allen T.

    2006-07-01

    Pipe break flow rates are calculated for a main feedwater line break (FWLB) in the main steam valve vault (MSVV) for a PWR Steam Generator Replacement (SGR). A reverse flow limiter is installed in the original steam generator (OSG) feedwater nozzle to limit the blowdown flowrate in the event of a postulated FWLB. This feature is not incorporated in the replacement steam generator (RSG) design. The change in RSG nozzle design in conjunction with new operating conditions results in increased FWLB mass and energy releases which can impact environmental temperatures and pressures and flooding levels. In the United States, benchmarking for safety related analyses is necessary in consideration of 10CFR50.59 requirements. RELAP5/MOD3 is used to model the pipe break flowrates for a FWLB at different break locations. The benchmark FWLB blowdown releases are larger than the OSG design basis blowdown releases due to differences in RELAP5/MOD3 versions which are found to have different algorithms for subcooled choked flow. The SGR FWLB blowdown release rates are determined to have minimal impact on the compartment temperature and pressure response. However, the flooding levels and associated equipment qualification are potentially impacted. Modeling techniques used to minimize the impact of the SGR blowdown releases on MSVV flooding levels include modeling flashing effects, more realistic RSG temperature distribution, inventory depletion and Auxiliary Feedwater (AFW) flow initiation time, and considering loss of offsite power scenarios. A detailed flooding hazard evaluation is needed, which considers the actual main feedwater isolation times to ensure that environmentally qualified safety related components, required to mitigate the effects of a FWLB inside the MSVV, can perform their safety function prior to being submerged. (authors)

  1. The {open_quotes}leak-before-break{close_quotes} applicability in decision support system {open_quotes}strength{close_quotes}

    SciTech Connect (OSTI)

    Torop, V.M.; Orynyak, I.V.; Kutovoy, O.L.

    1997-04-01

    A software decision support system, STRENGTH, for application of leak before break analysis, is described. The background methodology and sample application are outlined. The program allows multioptional computation of loading parameters for different types of defects, and variable properties for metals and welded joints. Structural strength is assessed, and service life predictions are made. The program is used to analyze specific defects identified by nondestructive testing.

  2. Assessment of RELAP/MOD3 using BETHSY 6.2TC 6-inch cold leg side break comparative test

    SciTech Connect (OSTI)

    Chung, Young-Jong; Jeong, Jae-Jun; Chang, Won-Pyo; Kim, Dong-Su

    1996-10-01

    This report presents the results of the RELAP5/MOD3 Version 7j assessment on BETHSY 6.2TC. BETHSY 6.2TC test corresponding to a six inch cold leg break LOCA of the Pressurizer Water Reactor(PWR). The primary objective of the test was to provide reference data of two facilities of different scales (BETHSY and LSTF facility). On the other hand, the present calculation aims at analysis of RELAP5/N4OD3 capability on the small break LOCA simulation, The results of calculation have shown that the RELAP5/MOD3 reasonably predicts occurrences as well as trends of the major phenomena such as primary pressure, timing of loop seal clearing, liquid hold up, etc. However, some disagreements also have been found in the predictions of loop seal clearing, collapsed core water level after loop seal clearing, and accumulator injection behaviors. For better understanding of discrepancies in same predictions, several sensitivity calculations have been performed as well. These include the changes of two-phase discharge coefficient at the break junction and some corrections of the interphase drag term. As result, change of a single parameter has not improved the overall predictions and it has been found that the interphase drag model has still large uncertainties.

  3. Reciprocal Regulation of Hypoxia-Inducible Factor 2α and GLI1 Expression Associated With the Radioresistance of Renal Cell Carcinoma

    SciTech Connect (OSTI)

    Zhou, Jiancheng; Wu, Kaijie; Gao, Dexuan; Zhu, Guodong; Wu, Dapeng; Wang, Xinyang; Chen, Yule; Du, Yuefeng; Song, Wenbin; Ma, Zhenkun; Authement, Craig; Saha, Debabrata; Hsieh, Jer-Tsong; He, Dalin

    2014-11-15

    Purpose: Renal cell carcinoma (RCC) is often considered a radioresistant tumor, but the molecular mechanism underlying its radioresistance is poorly understood. This study explored the roles of hypoxia-inducible factor 2α (HIF2α) and sonic hedgehog (SHH)-GLI1 signaling in mediating the radioresistance of RCC cells and to unveil the interaction between these 2 signaling pathways. Methods and Materials: The activities of SHH-GLI1 signaling pathway under normoxia and hypoxia in RCC cells were examined by real-time polymerase chain reaction, Western blot, and luciferase reporter assay. The expression of HIF2α and GLI1 in RCC patients was examined by immunohistochemistry, and their correlation was analyzed. Furthermore, RCC cells were treated with HIF2α-specific shRNA (sh-HIF2α), GLI1 inhibitor GANT61, or a combination to determine the effect of ionizing radiation (IR) on RCC cells based on clonogenic assay and double-strand break repair assay. Results: RCC cells exhibited elevated SHH-GLI1 activities under hypoxia, which was mediated by HIF2α. Hypoxia induced GLI1 activation through SMO-independent pathways that could be ablated by PI3K inhibitor or MEK inhibitor. Remarkably, the SHH-GLI1 pathway also upregulated HIF2α expression in normoxia. Apparently, there was a positive correlation between HIF2α and GLI1 expression in RCC patients. The combination of sh-HIF2α and GLI1 inhibitor significantly sensitized RCC cells to IR. Conclusions: Cross-talk between the HIF2α and SHH-GLI1 pathways was demonstrated in RCC. Cotargeting these 2 pathways, significantly sensitizing RCC cells to IR, provides a novel strategy for RCC treatment.

  4. Mode of ATM-dependent suppression of chromosome translocation

    SciTech Connect (OSTI)

    Yamauchi, Motohiro; Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer We addressed how ATM suppresses frequency of chromosome translocation. Black-Right-Pointing-Pointer We found ATM/p53-dependent G1 checkpoint suppresses translocation frequency. Black-Right-Pointing-Pointer We found ATM and DNA-PKcs function in a common pathway to suppress translocation. -- Abstract: It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  5. Radium-223 in the Treatment of Osteoblastic Metastases: A Critical Clinical Review

    SciTech Connect (OSTI)

    Humm, John L.; Sartor, Oliver; Parker, Chris; Bruland, Oyvind S.; Macklis, Roger

    2015-04-01

    The element radium (Ra) was discovered by the Curies in 1898 and within a decade was in broad scientific testing for the management of several forms of cancer. The compound was known to give rise to a series of both high-energy particulate and penetrating γ-emissions. The latter found an important role in early 20th century brachytherapy applications, but the short-range α-particles seemed much less useful. Although highly cytotoxic when released within a few cell diameters of critical cell nuclei, the dense double-strand break damage was poorly repaired, and concerns regarding treatment-related toxicities and secondary malignancies halted clinical development. Moreover, the most common isotope of Ra has an exceptionally long half-life (>1600 years for {sup 226}Ra) that proved daunting when aiming for a systemic cancer therapy. Fortunately, other radium isotopes have more convenient half-lives while still producing cytotoxic α particles. Radium-223 dichloride has a half-life of 11.4 days, and this isotope was identified as an excellent candidate for radionuclide therapy of cancers metastatic to bone. The calcium-mimetic chemical properties of the radium allowed intravenous infusion with rapid uptake to sites of new bone formation. The highly efficient bone localization suggested a potential therapeutic role for osteoblastic bone metastases, and a series of phase 1, 2, and 3 clinical trials was undertaken to explore this possibility. This series of clinical explorations culminated in the ALSYMPCA trial, an international, placebo-controlled, phase 3 study that accrued 921 symptomatic men with bone-metastatic, castrate-resistant prostate cancer. Results of this trial demonstrated a prolongation of overall survival, and regulatory agencies around the world have now approved this product as a treatment for advanced prostate cancer.

  6. STEAM LINE BREAK AND STATION BLACKOUT TRANSIENTS FOR PROLIFERATION RESISTANT HEXAGONAL TIGHT LATTICE BWR.

    SciTech Connect (OSTI)

    ROHATGI,U.S.; JO,J.; CHUNG,B.D.; TAKAHASHI,H.

    2002-06-09

    pitch lattice core: the Station Blackout and the Main Steam Line Break events. The results of the analyses indicate that the HCBWR system will be safely brought to the shutdown condition for these transients.

  7. Steam Line Break and Station Blackout Transients for Proliferation Resistant Hexagonal Tight Lattice BWR

    SciTech Connect (OSTI)

    Upendra Rohatgi; Jae Jo; Bub Dong Chung; Hiroshi Takahashi [Brookhaven National Laboratory, Energy Sciences and Technology Department, Upton, New York 11973 (United States); Downar, T.J. [Purdue University, School of Nuclear Engineering, West Lafayette, IN 47906-1290 (United States)

    2002-07-01

    Safety analyses of a proliferation resistant, economically competitive, high conversion, boiling water reactor (HCBWR) fueled with fissile plutonium and fertile thorium oxide fuel elements, and with passive safety systems are presented here. The HCBWR developed here is characterized by a very tight lattice with a relatively small water volume fraction in the core which therefore operates with a fast reactor neutron spectrum, and a considerably improved neutron economy compared to the current generation of Light Water Reactors. A tight lattice BWR core has very narrow flow channels with a hydraulic diameter less than half of the regular BWR core. The tight lattice core presented a special challenge to core cooling, because of reduced water inventory and high friction in the core. The primary safety concern when reducing the moderator to fuel ratio and when using a tightly packed lattice arrangement is to maintain adequate cooling of the core during both normal operation and accident scenarios. In the preliminary HCBWR design, the core has been placed in a vessel with a large chimney section, and the vessel is connected with an Isolation Cooling System (ICS). The vessel is placed in a containment with a Gravity Driven Cooling System (GDCS) and a Passive Containment Cooling System (PCCS) in a configuration similar to General Electric's (GE) Simplified Boiling Water Reactor (SBWR). The safety systems are similar to the SBWR; the ICS and PCCS are scaled with power. An internal recirculation pump was placed in the downcomer to augment the buoyancy head provided by the chimney. The buoyancy provided by the chimney alone could not generate sufficient recirculation in the vessel since the tight lattice configuration resulted in much larger friction in the core than the SBWR. A modified RELAP5 Code was used to simulate and analyze two of the most limiting events for a tight pitch lattice core: the Station Blackout and the Main Steam Line Break events. The constitutive

  8. Development and validation of nondestructive inspection techniques for composite doubler repairs on commercial aircraft

    SciTech Connect (OSTI)

    Roach, D.; Walkington, P.

    1998-05-01

    Composite doublers, or repair patches, provide an innovative repair technique which can enhance the way aircraft are maintained. Instead of riveting multiple steel or aluminum plates to facilitate an aircraft repair, it is possible to bond a single boron-epoxy composite doubler to the damaged structure. In order for the use of composite doublers to achieve widespread use in the civil aviation industry, it is imperative that methods be developed which can quickly and reliably assess the integrity of the doubler. In this study, a specific composite application was chosen on an L-1011 aircraft in order to focus the tasks on application and operation issues. Primary among inspection requirements for these doublers is the identification of disbonds, between the composite laminate and aluminum parent material, and delaminations in the composite laminate. Surveillance of cracks or corrosion in the parent aluminum material beneath the doubler is also a concern. No single nondestructive inspection (NDI) method can inspect for every flaw type, therefore it is important to be aware of available NDI techniques and to properly address their capabilities and limitations. A series of NDI tests were conducted on laboratory test structures and on full-scale aircraft fuselage sections. Specific challenges, unique to bonded composite doubler applications, were highlighted. An array of conventional and advanced NDI techniques were evaluated. Flaw detection sensitivity studies were conducted on applicable eddy current, ultrasonic, X-ray and thermography based devices. The application of these NDI techniques to composite doublers and the results from test specimens, which were loaded to provide a changing flaw profile, are presented in this report. It was found that a team of these techniques can identify flaws in composite doubler installations well before they reach critical size.

  9. JAG Tearing Technique with Radiofrequency Guide Wire for Aortic Fenestration in Thoracic Endovascular Aneurysm Repair

    SciTech Connect (OSTI)

    Ricci, Carmelo; Ceccherini, Claudio Leonini, Sara; Cini, Marco; Vigni, Francesco; Neri, Eugenio; Tucci, Enrico; Benvenuti, Antonio; Tommasino, Giulio; Sassi, Carlo

    2012-02-15

    An innovative approach, the JAG tearing technique, was performed during thoracic endovascular aneurysm repair in a patient with previous surgical replacement of the ascending aorta with a residual uncomplicated type B aortic dissection who developed an aneurysm of the descending thoracic aorta with its lumen divided in two parts by an intimal flap. The proximal landing zone was suitable to place a thoracic stent graft. The distal landing zone was created by cutting the intimal flap in the distal third of the descending thoracic aorta with a radiofrequency guide wire and intravascular ultrasound catheter.

  10. Failures and repairs of headers and drums in fossil fired boilers

    SciTech Connect (OSTI)

    Thielsch, H.; Cone, F.

    1995-12-01

    This paper discusses failures which have occurred in a number of thick-walled pressure vessels including superheater and reheat outlet headers, and med and steam drums in fossil fired boilers. It provides details regarding the causes of failure, which range from original manufacturing defects to service-related deterioration such as creep and thermal fatigue. It also provides information regarding inspection techniques which are capable of detecting similar conditions before they have reached dangerous levels of deterioration. Finally, it provides details pertaining to techniques used to successfully repair these pressure vessels when they have failed.

  11. Exposure Evaluation for Benzene, Lead and Noise in Vehicle and Equipment Repair Shops

    SciTech Connect (OSTI)

    Sweeney, Lynn C.

    2013-04-01

    An exposure assessment was performed at the equipment and vehicle maintenance repair shops operating at the U. S. Department of Energy Hanford site, in Richland, Washington. The maintenance shops repair and maintain vehicles and equipment used in support of the Hanford cleanup mission. There are three general mechanic shops and one auto body repair shop. The mechanics work on heavy equipment used in construction, cranes, commercial motor vehicles, passenger-type vehicles in addition to air compressors, generators, and farm equipment. Services include part fabrication, installation of equipment, repair and maintenance work in the engine compartment, and tire and brake services. Work performed at the auto body shop includes painting and surface preparation which involves applying body filler and sanding. 8-hour time-weighted-average samples were collected for benzene and noise exposure and task-based samples were collected for lead dust work activities involving painted metal surfaces. Benzene samples were obtained using 3M™ 3520 sampling badges and were analyzed for additional volatile organic compounds. These compounds were selected based on material safety data sheet information for the aerosol products used by the mechanics for each day of sampling. The compounds included acetone, ethyl ether, toluene, xylene, VM&P naphtha, methyl ethyl ketone, and trichloroethylene. Laboratory data for benzene, VM&P naphtha, methyl ethyl ketone and trichloroethylene were all below the reporting detection limit. Airborne concentrations for acetone, ethyl ether, toluene and xylene were all less than 10% of their occupational exposure limit. The task-based samples obtained for lead dusts were submitted for a metal scan analysis to identify other metals that might be present. Laboratory results for lead dusts were all below the reporting detection limit and airborne concentration for the other metals observed in the samples were less than 10% of the occupational exposure limit

  12. Dofasco`s No. 4 blast furnace hearth breakout, repair and rescue

    SciTech Connect (OSTI)

    Donaldson, R.J.; Fischer, A.J.; Sharp, R.M.; Stothart, D.W.

    1995-12-01

    On May 5, 1994, after producing 9.5 million metric tons of iron, Dofasco`s No. 4 Blast Furnace experienced a hearth breakout 250 millimeters below the west taphole. The hot metal spill caused a fire resulting in severe damage and 33 days of lost production. During a 26-day period, electrical wiring, water drainage systems and both tapholes were repaired. Recovery from an unprepared furnace stop of this length, with the deadman depleted is difficult. To aid with the rescue Hoogovens-designed oxygen/fuel lances were commissioned. The furnace recovery began with a lance in each taphole and all tuyeres plugged. Six days after startup the furnace was casting into torpedo cars, and after nine days operation had returned to normal. This incident prompted Dofasco to expand the hearth monitoring system to detect and prevent similar occurrences. During the repair, 203 new thermocouples were installed in the hearth, concentrating on the tapholes and elephant foot areas. These thermocouples were installed at various depths and locations to allow heat flux calculations. This hearth monitoring system has already identified other problem areas and provided valuable information about hearth drainage patterns. This information has allowed them to develop control strategies to manage localized problem areas.

  13. An investigation of penetrant techniques for detection of machining-induced surface-breaking cracks on monolithic ceramics

    SciTech Connect (OSTI)

    Forster, G.A.; Ellingson, W.A.

    1996-02-01

    The purpose of this effort was to evaluate penetrant methods for their ability to detect surface-breaking cracks in monolithic ceramic materials with an emphasis on detection of cracks generated by machining. There are two basic penetrant types, visible and fluorescent. The visible penetrant method is usually augmented by powder developers and cracks detected can be seen in visible light. Cracks detected by fluorescent penetrant are visible only under ultraviolet light used with or without a developer. The developer is basically a powder that wicks up penetrant from a crack to make it more observable. Although fluorescent penetrants were recommended in the literature survey conducted early in this effort, visible penetrants and two non-standard techniques, a capillary gaseous diffusion method under development at the institute of Chemical Physics in Moscow, and the {open_quotes}statiflux{close_quotes} method which involves use of electrically charged particles, were also investigated. SiAlON ring specimens (1 in. diameter, 3/4 in. wide) which had been subjected to different thermal-shock cycles were used for these tests. The capillary gaseous diffusion method is based on ammonia; the detector is a specially impregnated paper much like litmus paper. As expected, visible dye penetrants offered no detection sensitivity for tight, surface-breaking cracks in ceramics. Although the non-standard statiflux method showed promise on high-crack-density specimens, it was ineffective on limited-crack-density specimens. The fluorescent penetrant method was superior for surface-breaking crack detection, but successful application of this procedure depends greatly on the skill of the user. Two presently available high-sensitivity fluorescent penetrants were then evaluated for detection of microcracks on Si{sub 3}N{sub 4} and SiC from different suppliers. Although 50X optical magnification may be sufficient for many applications, 200X magnification provides excellent delectability.

  14. Assessment of a large break loss of coolant accident scenario requiring operator action to initiate safety injection

    SciTech Connect (OSTI)

    Grendys, R.C.; Nissley, M.E.; Baker, D.C.

    1996-11-01

    As part of the licensing basis for a nuclear power plant, the acceptability of the Emergency Core Cooling Systems (ECCS) following a postulated Loss-of-Coolant Accident (LOCA) as described in the Code of Federal Regulations (CFR), Title 10, Chapter 1, Part 50.46, must be verified. The LOCA analysis is performed with an acceptable ECCS Evaluation Model and results must show compliance with the 10 CFR 50.46 acceptance criteria. Westinghouse Electric Corporation performs Large and Small Break LOCA and LOCA-related analyses to support the licensing basis of various nuclear power plants and also performs evaluations against the licensing basis analyses as required. Occasionally, the need arises for the holder of an operating license of a nuclear power plant to submit a Licensee Event Report (LER) to the US Nuclear Regulatory Commission (USNRC) for any event of the type described in the Code of Federal Regulations, Title 10, Chapter 1, Part 50.73. To support the LER, a Justification for Past Operation (JPO) may be performed to assess the safety consequences and implications of the event based on previous operating conditions. This paper describes the work performed for the Large Break LOCA to assess the impact of an event discovered by Florida Power and Light and reported in LER-94-005-02. For this event, it was determined that under certain circumstances, operator action would have been required to initiate safety injection (SI), thus challenging the acceptability of the ECCS. This event was specifically addressed for the Large Break LOCA by using an advanced thermal hydraulic analysis methodology with realistic input assumptions.

  15. Nonlinear delayed symmetry breaking in a solid excited by hard x-ray free electron laser pulses

    SciTech Connect (OSTI)

    Ferrer, A.; Johnson, J. A. Mariager, S. O.; Grbel, S.; Staub, U.; Huber, T.; Trant, M.; Johnson, S. L.; Zhu, D.; Chollet, M.; Robinson, J.; Lemke, H. T.; Ingold, G.; Beaud, P.; Milne, C.

    2015-04-13

    We have studied the ultrafast changes of electronic states in bulk ZnO upon intense hard x-ray excitation from a free electron laser. By monitoring the transient anisotropy induced in an optical probe beam, we observe a delayed breaking of the initial c-plane symmetry of the crystal that lasts for several picoseconds. Interaction with the intense x-ray pulses modifies the electronic state filling in a manner inconsistent with a simple increase in electronic temperature. These results may indicate a way to use intense ultrashort x-ray pulses to investigate high-energy carrier dynamics and to control certain properties of solid-state materials.

  16. Application of the leak-before-break concept to the primary circuit piping of the Leningrad NPP

    SciTech Connect (OSTI)

    Eperin, A.P.; Zakharzhevsky, Yu.O.; Arzhaev, A.I.

    1997-04-01

    A two-year Finnish-Russian cooperation program has been initiated in 1995 to demonstrate the applicability of the leak-before-break concept (LBB) to the primary circuit piping of the Leningrad NPP. The program includes J-R curve testing of authentic pipe materials at full operating temperature, screening and computational LBB analyses complying with the USNRC Standard Review Plan 3.6.3, and exchange of LBB-related information with emphasis on NDE. Domestic computer codes are mainly used, and all tests and analyses are independently carried out by each party. The results are believed to apply generally to RBMK type plants of the first generation.

  17. Three-body break-up in deuteron-deuteron scattering at 65 MeV/nucleon

    SciTech Connect (OSTI)

    Ramazani-Moghaddam-Arani, A.; Amir-Ahmadi, H. R.; Biegun, A.; Joulaeizadeh, L.; Kalantar-Nayestanaki, N.; Mardanpour, H.; Messchendorp, J. G.; Moeini, H.; Shende, S. V.; Bacher, A. D.; Bailey, C. D.; Stephenson, E. J.; Eslami-Kalantari, M.; Gasparic, I.; Kistryn, St.; Sworst, R.; Kozela, A.; Micherdzinska, A. M.; Stephan, E.

    2011-02-15

    In an experiment with a 65 MeV/nucleon polarized deuteron beam on a liquid-deuterium target at Kernfysisch Versneller Instituut, several multibody final states in deuteron-deuteron scattering were identified. For these measurements, a unique and advanced detection system, called the Big Instrument for Nuclear-polarization Analysis, was utilized. We demonstrate the feasibility of measuring vector and tensor polarization observables of the deuteron break-up reaction leading to a three-body final state. The polarization observables were determined with high precision in a nearly background-free experiment. The analysis procedure and some results are presented.

  18. Planning and care mark repair of 14-year old leak in Kuwait Oil Co. LPG tank 95

    SciTech Connect (OSTI)

    Shtayieh, S.

    1983-01-10

    This paper points out that the leak, which had been present for such a long time, completely saturated the perlite insulation with hydrocarbons, thus rendering the entire operation of inspection, repair, and maintenance of the inner tank a hazardous operation. It emphasizes the safety aspects, which were complicated by the saturated perlite as well as by the fact that the tank is situated in the middle of the LPG storage area with LPG tanks on either side. Tank design, making preparations, inspection, and repair are discussed. The fact that the leaking flanges were originally installed damaged, indicated the future need of tighter company quality control of all contractors work.

  19. Operational results of shaft repair by installing stave type cooler at Kimitsu Nos. 3 and 4 blast furnaces

    SciTech Connect (OSTI)

    Oda, Hiroshi; Amano, Shigeru; Sakamoto, Aiichiro; Anzai, Osamu; Nakagome, Michiru; Kuze, Toshisuke; Imuta, Akira

    1997-12-31

    Nos. 3 and 4 blast furnaces in Nippon Steel Corporation Kimitsu Works were both initially fitted with cooling plate systems. With the aging of each furnace, the damage to their respective inner-shaft profiles had become serious. Thus, in order to prevent operational change and prolong the furnace life, the inner-shaft profile of each furnace was repaired by replacing the former cooling plate system with the stave type cooler during the two-week-shutdowns. With this repair, stability of burden descent and gas flow near the wall part of the furnace have been achieved. Thus the prolongation of the furnace life is naturally expected.

  20. Building a market for small wind: The break-even turnkey cost of residential wind systems in the United States

    SciTech Connect (OSTI)

    Edwards, Jennifer L.; Wiser, Ryan; Bolinger, Mark; Forsyth, Trudy

    2004-03-01

    Although small wind turbine technology and economics have improved in recent years, the small wind market in the United States continues to be driven in large part by state incentives, such as cash rebates, favorable loan programs, and tax credits. This paper examines the state-by-state economic attractiveness of small residential wind systems. Economic attractiveness is evaluated primarily using the break-even turnkey cost (BTC) of a residential wind system as the figure of merit. The BTC is defined here as the aggregate installed cost of a small wind system that could be supported such that the system owner would break even (and receive a specified return on investment) over the life of the turbine, taking into account current available incentives, the wind resource, and the retail electricity rate offset by on-site generation. Based on the analysis presented in this paper, we conclude that: (1) the economics of residential, grid-connected small wind systems is highly variable by state and wind resource class, (2) significant cost reductions will be necessary to stimulate widespread market acceptance absent significant changes in the level of policy support, and (3) a number of policies could help stimulate the market, but state cash incentives currently have the most significant impact, and will be a critical element of continued growth in this market.

  1. Coal-water slurry sprays from an electronically controlled accumulator fuel injection system: Break-up distances and times

    SciTech Connect (OSTI)

    Caton, J.A.; Payne, S.E.; Terracina, D.P.; Kihm, K.D.

    1993-12-31

    Experiments have been completed to characterize coal-water slurry sprays from an electronically-controlled accumulator fuel injection system of a diesel engine. The sprays were injected into a pressurized chamber equipped with windows. High speed movies, fuel pressures and needle lifts were obtained as a function of time, orifice diameter, coal loading, gas density in the chamber, and accumulator fuel pressure. For the base conditions (50% (by man) coal loading, 0.4 mm diameter nozzle hole, coal-water slurry pressure of 82 MPa (12,000 psi), and a chamber density of 25 kg/m{sup 3}), the break-up time was 0.30 ms. An empirical correlation for spray tip penetration, break-up time and initial jet velocity was developed. For the conditions of this study, the spray tip penetration and initial jet velocity were 15% greater for coal-water slurry than for diesel fuel or water. Results of this study and the correlation are specific to the tested coal-water slurry and are not general for other coal-water slurry fuels.

  2. Experiment data report for LOFT large-break loss-of-coolant experiment L2-5. [PWR

    SciTech Connect (OSTI)

    Bayless, P.D.; Divine, J.M.

    1982-08-01

    Selected pertinent and uninterpreted data from the third nuclear large break loss-of-coolant experiment (Experiment L2-5) conducted in the Loss-of-Fluid Test (LOFT) facility are presented. The LOFT facility is a 50-MW(t) pressurized water reactor (PWR) system with instruments that measure and provide data on the system thermal-hydraulic and nuclear conditions. The operation of the LOFT system is typical of large (approx. 1000 MW(e)) commercial PWR operations. Experiment L2-5 simulated a double-ended offset shear of a cold leg in the primary coolant system. The primary coolant pumps were tripped within 1 s after the break initiation, simulating a loss of site power. Consistent with the loss of power, the starting of the high- and low-pressure injection systems was delayed. The peak fuel rod cladding temperature achieved was 1078 +- 13 K. The emergency core cooling system re-covered the core and quenched the cladding. No evidence of core damage was detected.

  3. Inhibition of B-NHEJ in Plateau-Phase Cells Is Not a Direct Consequence of Suppressed Growth Factor Signaling

    SciTech Connect (OSTI)

    Singh, Satyendra K.; Bednar, Theresa; Zhang Lihua; Wu, Wenqi; Mladenov, Emil; Iliakis, George

    2012-10-01

    Purpose: It has long been known that the proliferation status of a cell is a determinant of radiation response, and the available evidence implicates repair of DNA double-strand breaks (DSBs) in the underlying mechanism. Recent results have shown that a novel, highly error-prone pathway of nonhomologous end joining (NHEJ) operating as backup (B-NHEJ) processes DSBs in irradiated cells when the canonical, DNA-PK (DNA-dependent protein kinase)-dependent pathway of NHEJ (D-NHEJ) is compromised. Notably, B-NHEJ shows marked reduction in efficiency when D-NHEJ-deficient cells cease to grow and enter a plateau phase. This phenomenon is widespread and observed in cells of different species with defects in core components of D-NHEJ, with the notable exception of DNA-PKcs (DNA-dependent protein kinase, catalytic subunit). Using new, standardized serum-deprivation protocols, we re-examine the growth requirements of B-NHEJ and test the role of epidermal growth factor receptor (EGFR) signaling in its regulation. Methods and Materials: DSB repair was measured by pulsed-field gel electrophoresis in cells maintained under different conditions of growth. Results: Serum deprivation in D-NHEJ-deficient cells causes a rapid reduction in B-NHEJ similar to that measured in normally growing cells that enter the plateau phase of growth. Upon serum deprivation, reduction in B-NHEJ activity is evident at 4 h and reaches a plateau reflecting maximum inhibition at 12-16 h. The inhibition is reversible, and B-NHEJ quickly recovers to the levels of actively growing cells upon supply of serum to serum-deprived cells. Chemical inhibition of EGFR in proliferating cells inhibits only marginally B-NHEJ and addition of EGFR in serum-deprived cells increases only a marginally B-NHEJ. Conclusions: The results document a rapid and fully reversible adaptation of B-NHEJ to growth activity and point to factors beyond EGFR in its regulation. They show notable differences in the regulation of error

  4. Survival Fraction at 2 Gy and γH2AX Expression Kinetics in Peripheral Blood Lymphocytes From Cancer Patients: Relationship With Acute Radiation-Induced Toxicities

    SciTech Connect (OSTI)

    Pouliliou, Stamatia E.; Dimitriou, Thespis; Giatromanolaki, Alexandra; Papazoglou, Dimitrios; Pappa, Aglaia; Pistevou, Kyriaki

    2015-07-01

    Purpose: Predictive assays for acute radiation toxicities would be clinically relevant in radiation oncology. We prospectively examined the predictive role of the survival fraction at 2 Gy (SF2) and of γH2AX (double-strand break [DSB] DNA marker) expression kinetics in peripheral blood mononuclear cells (PBMCs) from cancer patients before radiation therapy. Methods and Materials: SF2 was measured with Trypan Blue assay in the PBMCs from 89 cancer patients undergoing radiation therapy at 4 hours (SF2{sub [4h]}) and 24 hours (SF2{sub [24h]}) after ex vivo irradiation. Using Western blot analysis and band densitometry, we further assessed the expression of γH2AX in PBMC DNA at 0 hours, 30 minutes, and 4 hours (33 patients) and 0 hour, 4 hours, and 24 hours (56 patients), following ex vivo irradiation with 2 Gy. Appropriate ratios were used to characterize each patient, and these were retrospectively correlated with early radiation therapy toxicity grade. Results: The SF2{sub (4h)} was inversely correlated with the toxicity grade (P=.006). The γH2AX-ratio{sub (30min)} (band density of irradiated/non-irradiated cells at 30 minutes) revealed, similarly, a significant inverse association (P=.0001). The DSB DNA repair rate from 30 minutes to 4 hours, calculated as the relative RγH2AX-ratio (γH2AX-ratio{sub (4h)}/γH2AX-ratio{sub (30min)}) showed a significant direct association with high toxicity grade (P=.01). Conclusions: Our results suggest that SF2 is a significant radiation sensitivity index for patients undergoing radiation therapy. γH2AX Western blot densitometry analysis provided 2 important markers of normal tissue radiation sensitivity. Low γH2AX expression at 30 minutes was linked with high toxicity grade, suggesting that poor γH2AX repair activity within a time frame of 30 minutes after irradiation predicts for poor radiation tolerance. On the other hand, rapid γH2AX content restoration at 4 hours after irradiation, compatible with

  5. Designer's guidebook for first wall/blanket/shield assembly, maintenance, and repair

    SciTech Connect (OSTI)

    Not Available

    1983-12-30

    This is the initial issue of the guidebook. Since a guidebook of this type must incorporate information concerning a wide range of subjects, much additional data will eventually be included. The guidebook will document, in summary and easily referenceable form, data, designs, design concepts, design guidelines and background information useful to the FWBS and to the Maintenance System designer. In providing guidelines for the AMR of the FWBS, the guidebook must, of necessity, include guidelines for all aspects of maintenance associated with the FWBS. These include most maintenance operations within the reactor room necessary to gain access, identify faults, and handle equipment related to FWBS maintenance. In addition, the guidelines include those required to define facility requirements for handling and repair of FWBS and related reactor components external to the reactor room. Particular emphasis is given to remote maintenance design and operations.

  6. Method and apparatus for in-system redundant array repair on integrated circuits

    DOE Patents [OSTI]

    Bright, Arthur A.; Crumley, Paul G.; Dombrowa, Marc B.; Douskey, Steven M.; Haring, Rudolf A.; Oakland, Steven F.; Ouellette, Michael R.; Strissel, Scott A.

    2008-07-08

    Disclosed is a method of repairing an integrated circuit of the type comprising of a multitude of memory arrays and a fuse box holding control data for controlling redundancy logic of the arrays. The method comprises the steps of providing the integrated circuit with a control data selector for passing the control data from the fuse box to the memory arrays; providing a source of alternate control data, external of the integrated circuit; and connecting the source of alternate control data to the control data selector. The method comprises the further step of, at a given time, passing the alternate control data from the source thereof, through the control data selector and to the memory arrays to control the redundancy logic of the memory arrays.

  7. Method and apparatus for in-system redundant array repair on integrated circuits

    DOE Patents [OSTI]

    Bright, Arthur A.; Crumley, Paul G.; Dombrowa, Marc B.; Douskey, Steven M.; Haring, Rudolf A.; Oakland, Steven F.; Ouellette, Michael R.; Strissel, Scott A.

    2008-07-29

    Disclosed is a method of repairing an integrated circuit of the type comprising of a multitude of memory arrays and a fuse box holding control data for controlling redundancy logic of the arrays. The method comprises the steps of providing the integrated circuit with a control data selector for passing the control data from the fuse box to the memory arrays; providing a source of alternate control data, external of the integrated circuit; and connecting the source of alternate control data to the control data selector. The method comprises the further step of, at a given time, passing the alternate control data from the source thereof, through the control data selector and to the memory arrays to control the redundancy logic of the memory arrays.

  8. Method and apparatus for in-system redundant array repair on integrated circuits

    DOE Patents [OSTI]

    Bright, Arthur A.; Crumley, Paul G.; Dombrowa, Marc B.; Douskey, Steven M.; Haring, Rudolf A.; Oakland, Steven F.; Ouellette, Michael R.; Strissel, Scott A.

    2007-12-18

    Disclosed is a method of repairing an integrated circuit of the type comprising of a multitude of memory arrays and a fuse box holding control data for controlling redundancy logic of the arrays. The method comprises the steps of providing the integrated circuit with a control data selector for passing the control data from the fuse box to the memory arrays; providing a source of alternate control data, external of the integrated circuit; and connecting the source of alternate control data to the control data selector. The method comprises the further step of, at a given time, passing the alternate control data from the source thereof, through the control data selector and to the memory arrays to control the redundancy logic of the memory arrays.

  9. Potential inspection, maintenance and repair techniques for the OTEC (Ocean Thermal Energy Conversion) systems

    SciTech Connect (OSTI)

    Not Available

    1983-02-01

    One of the major post-installation considerations of the OTEC platforms is the performance of underwater inspection, maintenance and repair (IMR) during their 30-year design life. In order to assist in the conceptual development of an IMR program, this study was undertaken using the two OTEC candidate configurations as a baseline. The objectives of the study were: (1) conduct an inventory of underwater Non-Destructive Examination (NDE) devices including a description of their performance capabilities, dimensional data, the areas of the various structures where they are most applicable, and a narrative description of the level of performance attained to date; (2) and to conduct an inventory of NDE device deployment vehicles which also includes a description of their performance capabilities, dimensional data, areas of the platform where they are most applicable as now designed and a relative comparison of these vehicles as to their ability to deploy the devices described in (1) above.

  10. Design structure for in-system redundant array repair in integrated circuits

    DOE Patents [OSTI]

    Bright, Arthur A.; Crumley, Paul G.; Dombrowa, Marc; Douskey, Steven M.; Haring, Rudolf A.; Oakland, Steven F.; Quellette, Michael R.; Strissel, Scott A.

    2008-11-25

    A design structure for repairing an integrated circuit during operation of the integrated circuit. The integrated circuit comprising of a multitude of memory arrays and a fuse box holding control data for controlling redundancy logic of the arrays. The design structure provides the integrated circuit with a control data selector for passing the control data from the fuse box to the memory arrays; providing a source of alternate control data, external of the integrated circuit; and connecting the source of alternate control data to the control data selector. The design structure further passes the alternate control data from the source thereof, through the control data selector and to the memory arrays to control the redundancy logic of the memory arrays.

  11. Meiotic interstrand DNA damage escapes paternal repair and causes chromosomal aberrations in the zygote by maternal misrepair

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

    Marchetti, Francesco; Bishop, Jack; Gingerich, John; Wyrobek, Andrew J.

    2015-01-08

    De novo point mutations and chromosomal structural aberrations (CSA) detected in offspring of unaffected parents show a preferential paternal origin with higher risk for older fathers. Studies in rodents suggest that heritable mutations transmitted from the father can arise from either paternal or maternal misrepair of damaged paternal DNA, and that the entire spermatogenic cycle can be at risk after mutagenic exposure. Understanding the susceptibility and mechanisms of transmission of paternal mutations is important in family planning after chemotherapy and donor selection for assisted reproduction. We report that treatment of male mice with melphalan (MLP), a bifunctional alkylating agent widelymore » used in chemotherapy, induces DNA lesions during male mouse meiosis that persist unrepaired as germ cells progress through DNA repair-competent phases of spermatogenic development. After fertilization, unrepaired sperm DNA lesions are mis-repaired into CSA by the egg's DNA repair machinery producing chromosomally abnormal offspring. In conclusion, these findings highlight the importance of both pre- and post-fertilization DNA repair in assuring the genomic integrity of the conceptus.« less

  12. Melatonin Protects Human Cells from Clustered DNA Damages, Killing and Acquisition of Soft Agar Growth Induced by X-rays or 970 MeV/n Fe ions

    SciTech Connect (OSTI)

    Das, B.; Sutherland, B.; Bennett, P. V.; Cutter, N. C.; Sutherland, J. C.

    2011-06-01

    We tested the ability of melatonin (N-acetyl-5 methoxytryptamine), a highly effective radical scavenger and human hormone, to protect DNA in solution and in human cells against induction of complex DNA clusters and biological damage induced by low or high linear energy transfer radiation (100 kVp X-rays, 970 MeV/nucleon Fe ions). Plasmid DNA in solution was treated with increasing concentrations of melatonin (0.0-3.5 mM) and were irradiated with X-rays. Human cells (28SC monocytes) were also irradiated with X-rays and Fe ions with and without 2 mM melatonin. Agarose plugs containing genomic DNA were subjected to Contour Clamped Homogeneous Electrophoretic Field (CHEF) followed by imaging and clustered DNA damages were measured by using Number Average length analysis. Transformation experiments on human primary fibroblast cells using soft agar colony assay were carried out which were irradiated with Fe ions with or without 2 mM melatonin. In plasmid DNA in solution, melatonin reduced the induction of single- and double-strand breaks. Pretreatment of human 28SC cells for 24 h before irradiation with 2 mM melatonin reduced the level of X-ray induced double-strand breaks by {approx}50%, of abasic clustered damages about 40%, and of Fe ion-induced double-strand breaks (41% reduction) and abasic clusters (34% reduction). It decreased transformation to soft agar growth of human primary cells by a factor of 10, but reduced killing by Fe ions only by 20-40%. Melatonin's effective reduction of radiation-induced critical DNA damages, cell killing, and striking decrease of transformation suggest that it is an excellent candidate as a countermeasure against radiation exposure, including radiation exposure to astronaut crews in space travel.

  13. Simulation of the OECD Main-Steam-Line-Break Benchmark Exercise 3 Using the Coupled RELAP5/PANTHER Codes

    SciTech Connect (OSTI)

    Schneidesch, Christophe R.; Zhang Jinzhao

    2004-04-15

    The RELAP5 best-estimate thermal-hydraulic system code has been coupled with the PANTHER three-dimensional neutron kinetics code via the TALINK dynamic data exchange control and processing tool. The coupled RELAP5/PANTHER code package has been qualified and will be used at Tractebel Engineering (TE) for analyzing asymmetric pressurized water reactor (PWR) accidents with strong core-system interactions. The Organization for Economic Cooperation and Development/U.S. Nuclear Regulatory Commission PWR main-steam-line-break benchmark problem was analyzed as part of the qualification efforts to demonstrate the capability of the coupled code package of simulating such transients. This paper reports the main results of TE's contribution to the benchmark Exercise 3.

  14. Analysis of a double-ended cold-leg break simulation: THTF Test 3. 05. 5B. [PWR

    SciTech Connect (OSTI)

    Craddick, W.G.; Pevey, R.E.

    1982-09-01

    On July 3, 1980, an experiment was performed in the Oak Ridge National Laboratory Thermal-Hydraulic Test Facility that simulated a double-ended cold-leg break pressurized-water reactor (PWR) accident. Analysis of the experiment revealed that nuclear fuel rods exposed to the same hydrodynamic environment as that which existed in the experiment would have departed from nucleate boiling both earlier and later than the fuel rod simulator (FRS), depending on the size of the gap between the nuclear fuel pellets and cladding and on the initial power of the nuclear fuel rod. Comparison of the results of the current experiment, which used an FRS bundle with geometry similar to 17 x 17 PWR fuel assemblies, to the results of earlier experiments, which used an FRS bundle with geometry similar to 15 x 15 PWR fuel assemblies, revealed no differences that can be attributed to the difference in geometries.

  15. Belgian experience in applying the {open_quotes}leak-before-break{close_quotes} concept to the primary loop piping

    SciTech Connect (OSTI)

    Gerard, R.; Malekian, C.; Meessen, O.

    1997-04-01

    The Leak Before Break (LBB) concept allows to eliminate from the design basis the double-ended guillotine break of the primary loop piping, provided it can be demonstrated by a fracture mechanics analysis that a through-wall flaw, of a size giving rise to a leakage still well detectable by the plant leak detection systems, remains stable even under accident conditions (including the Safe Shutdown Earthquake (SSE)). This concept was successfully applied to the primary loop piping of several Belgian Pressurized Water Reactor (PWR) units, operated by the Utility Electrabel. One of the main benefits is to permit justification of supports in the primary loop and justification of the integrity of the reactor pressure vessel and internals in case of a Loss Of Coolant Accident (LOCA) in stretch-out conditions. For two of the Belgian PWR units, the LBB approach also made it possible to reduce the number of large hydraulic snubbers installed on the primary coolant pumps. Last but not least, the LBB concept also facilitates the steam generator replacement operations, by eliminating the need for some pipe whip restraints located close to the steam generator. In addition to the U.S. regulatory requirements, the Belgian safety authorities impose additional requirements which are described in details in a separate paper. An novel aspect of the studies performed in Belgium is the way in which residual loads in the primary loop are taken into account. Such loads may result from displacements imposed to close the primary loop in a steam generator replacement operation, especially when it is performed using the {open_quote}two cuts{close_quotes} technique. The influence of such residual loads on the LBB margins is discussed in details and typical results are presented.

  16. Metal inhibition of human alkylpurine-DNA-N-glycosylase activityin base excision repair

    SciTech Connect (OSTI)

    Wang, Ping; Guliaev, Anton B.; Hang, Bo

    2006-02-28

    Cadmium (Cd{sup 2+}), nickel (Ni{sup 2+}) and cobalt (Co{sup 2+}) are human and/or animal carcinogens. Zinc (Zn{sup 2+}) is not categorized as a carcinogen, and rather an essential element to humans. Metals were recently shown to inhibit DNA repair proteins that use metals for their function and/or structure. Here we report that the divalent ions Cd{sup 2+}, Ni{sup 2+}, and Zn{sup 2+} can inhibit the activity of a recombinant human N-methylpurine-DNA glycosylase (MPG) toward a deoxyoligonucleotide with ethenoadenine (var epsilonA). MPG removes a variety of toxic/mutagenic alkylated bases and does not require metal for its catalytic activity or structural integrity. At concentrations starting from 50 to 1000 {micro}M, both Cd{sup 2+} and Zn{sup 2+} showed metal-dependent inhibition of the MPG catalytic activity. Ni{sup 2+} also inhibited MPG, but to a lesser extent. Such an effect can be reversed with EDTA addition. In contrast, Co{sup 2+} and Mg{sup 2+} did not inhibit the MPG activity in the same dose range. Experiments using HeLa cell-free extracts demonstrated similar patterns of inactivation of the var epsilonA excision activity by the same metals. Binding of MPG to the substrate was not significantly affected by Cd{sup 2+}, Zn{sup 2+}, and Ni{sup 2+} at concentrations that show strong inhibition of the catalytic function, suggesting that the reduced catalytic activity is not due to altered MPG binding affinity to the substrate. Molecular dynamics (MD) simulations with Zn{sup 2+} showed that the MPG active site has a potential binding site for Zn{sup 2+}, formed by several catalytically important and conserved residues. Metal binding to such a site is expected to interfere with the catalytic mechanism of this protein. These data suggest that inhibition of MPG activity may contribute to metal genotoxicity and depressed repair of alkylation damage by metals in vivo.

  17. Pressure effects on magnetic pair-breaking in Mn- and Eu-substituted BaFe{sub 2}As{sub 2}

    SciTech Connect (OSTI)

    Rosa, P. F. S.; Garitezi, T. M.; Adriano, C.; Urbano, R. R.; Pagliuso, P. G.; Grant, T.; Fisk, Z.; Fernandes, R. M.

    2014-05-07

    We report a combined study of hydrostatic pressure (P ? 25 kbar) and chemical substitution on the magnetic pair-breaking effect in Eu- and Mn-substituted BaFe{sub 2}As{sub 2} single crystals. At ambient pressure, both substitutions suppress the superconducting (SC) transition temperature (T{sub c}) of BaFe{sub 2x}Co{sub x}As{sub 2} samples slightly under the optimally doped region, indicating the presence of a pair-breaking effect. At low pressures, an increase of T{sub c} is observed for all studied compounds followed by an expected decrease at higher pressures. However, in the Eu dilute system, T{sub c} further increases at higher pressure along with a narrowing of the SC transition, suggesting that a pair-breaking mechanism reminiscent of the Eu Kondo single impurity regime is being suppressed by pressure. Furthermore, Electron Spin Resonance (ESR) measurements indicate the presence of Mn{sup 2+} and Eu{sup 2+} local moments and the microscopic parameters extracted from the ESR analysis reveal that the AbrikosovGor'kov expression for magnetic pair-breaking in a conventional sign-preserving superconducting state cannot describe the observed reduction of T{sub c}.

  18. The mystery of spectral breaks: Lyman continuum absorption by photon-photon pair production in the Fermi GeV spectra of bright blazars

    SciTech Connect (OSTI)

    Stern, Boris E. [Institute for Nuclear Research, Russian Academy of Sciences, Prospekt 60-letiya Oktyabrya 7a, Moscow 117312 (Russian Federation); Poutanen, Juri, E-mail: stern.boris@gmail.com, E-mail: juri.poutanen@utu.fi [Tuorla Observatory, University of Turku, Vislntie 20, FI-21500 Piikki (Finland)

    2014-10-10

    We re-analyze Fermi/LAT ?-ray spectra of bright blazars using the new Pass 7 version of the detector response files and detect breaks at ?5 GeV in the rest-frame spectra of 3C 454.3 and possibly also 4C +21.35, associated with the photon-photon pair production absorption by the He II Lyman continuum (LyC). We also detect significant breaks at ?20 GeV associated with hydrogen LyC in both the individual spectra and the stacked redshift-corrected spectrum of several bright blazars. The detected breaks in the stacked spectra univocally prove that they are associated with atomic ultraviolet emission features of the quasar broad-line region (BLR). The dominance of the absorption by the hydrogen Ly complex over He II, a small detected optical depth, and break energy consistent with head-on collisions with LyC photons imply that the ?-ray emission site is located within the BLR, but most of the BLR emission comes from a flat disk-like structure producing little opacity. Alternatively, the LyC emission region size might be larger than the BLR size measured from reverberation mapping, and/or the ?-ray emitting region is extended. These solutions would resolve the long-standing issue of how the multi-hundred GeV photons can escape from the emission zone without being absorbed by softer photons.

  19. Deterioration of Pracana Dam due to ASR. Main features and repair works

    SciTech Connect (OSTI)

    Matos, D.S.; Camelo, S.; Silva, H.S.; Pinho, J.S.

    1995-12-31

    Some of the Portuguese concrete dams show evidences of ASR. In majority the phenomena is still benign. However, in a few cases some significant deterioration of ASR type have malfunctions arose. In such cases deteriorations of ASR type have been detected while in the others the ASSR type prevail, depending on the type of aggregate. The paper reports the most important case of ASR in Portuguese concrete dams. Pracana dam is a buttress structures built in 1948-51, being the aggregates predominantly of quartzitic and metapellitic nature. Subsequently to the intense fracturing due to a quick concrete cooling during the first filling of the reservoir, high levels of expansion rates had been detected by means of monitoring system. After 8 years emptied reservoir, rehabilitation works took place in 1991-92 aiming at the concrete mass regeneration and the installation of an upstream face membrane, the improvement of spillway capacity and of the foundation performances. The behaviour of the dam as well as the performed tests (petrographic, mechanic, ultrasonic and expansibility ones) and repair works are described in the paper.

  20. Human HLTF mediates postreplication repair by its HIRAN domain-dependent replication fork remodelling

    SciTech Connect (OSTI)

    Achar, Yathish Jagadheesh; Balogh, David; Neculai, Dante; Juhasz, Szilvia; Morocz, Monika; Gali, Himabindu; Dhe-Paganon, Sirano; Venclovas, Česlovas; Haracska, Lajos

    2015-09-08

    Defects in the ability to respond properly to an unrepaired DNA lesion blocking replication promote genomic instability and cancer. Human HLTF, implicated in error-free replication of damaged DNA and tumour suppression, exhibits a HIRAN domain, a RING domain, and a SWI/SNF domain facilitating DNA-binding, PCNA-polyubiquitin-ligase, and dsDNA-translocase activities, respectively. Here, we investigate the mechanism of HLTF action with emphasis on its HIRAN domain. We found that in cells HLTF promotes the filling-in of gaps left opposite damaged DNA during replication, and this postreplication repair function depends on its HIRAN domain. Our biochemical assays show that HIRAN domain mutant HLTF proteins retain their ubiquitin ligase, ATPase and dsDNA translocase activities but are impaired in binding to a model replication fork. These data and our structural study indicate that the HIRAN domain recruits HLTF to a stalled replication fork, and it also provides the direction for the movement of the dsDNA translocase motor domain for fork reversal. We suggest functional similarities between the HIRAN, the OB, the HARP2, and other domains found in certain motor proteins, which may explain why only a subset of DNA translocases can carry out fork reversal.

  1. Evaluating indoor exposure modeling alternatives for LCA: A case study in the vehicle repair industry

    SciTech Connect (OSTI)

    Demou, Evangelia; Hellweg, Stefanie; Wilson, Michael P.; Hammond, S. Katharine; McKone, Thomas E.

    2009-05-01

    We evaluated three exposure models with data obtained from measurements among workers who use"aerosol" solvent products in the vehicle repair industry and with field experiments using these products to simulate the same exposure conditions. The three exposure models were the: 1) homogeneously-mixed-one-box model, 2) multi-zone model, and 3) eddy-diffusion model. Temporally differentiated real-time breathing zone volatile organic compound (VOC) concentration measurements, integrated far-field area samples, and simulated experiments were used in estimating parameters, such as emission rates, diffusivity, and near-field dimensions. We assessed differences in model input requirements and their efficacy for predictive modeling. The One-box model was not able to resemble the temporal profile of exposure concentrations, but it performed well concerning time-weighted exposure over extended time periods. However, this model required an adjustment for spatial concentration gradients. Multi-zone models and diffusion-models may solve this problem. However, we found that the reliable use of both these models requires extensive field data to appropriately define pivotal parameters such as diffusivity or near-field dimensions. We conclude that it is difficult to apply these models for predicting VOC exposures in the workplace. However, for comparative exposure scenarios in life-cycle assessment they may be useful.

  2. Sac Angiography and Glue Embolization in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysm

    SciTech Connect (OSTI)

    Koike, Yuya Nishimura, Jun-ichi Hase, Soichiro Yamasaki, Motoshige

    2015-04-15

    PurposeThe purpose of this study was to demonstrate a sac angiography technique and evaluate the feasibility of N-butyl cyanoacrylate (NBCA) embolization of the ruptured abdominal aortic aneurysm (AAA) sac in emergency endovascular aneurysm repair (EVAR) in hemodynamically unstable patients.MethodsA retrospective case series of three patients in whom sac angiography was performed during emergency EVAR for ruptured AAA was reviewed. After stent graft deployment, angiography within the sac of aneurysm (sac angiography) was performed by manually injecting 10 ml of contrast material through a catheter to identify the presence and site of active bleeding. In two patients, sac angiography revealed active extravasation of the contrast material, and NBCA embolization with a coaxial catheter system was performed to achieve prompt sealing.ResultsSac angiography was successful in all three patients. In the two patients who underwent NBCA embolization for aneurysm sac bleeding, follow-up computed tomography (CT) images demonstrated the accumulation of NBCA consistent with the bleeding site in preprocedural CT images.ConclusionsEVAR is associated with a potential risk of ongoing bleeding from type II or IV endoleaks into the disrupted aneurysm sac in patients with severe coagulopathy. Therefore, sac angiography and NBCA embolization during emergency EVAR may represent a possible technical improvement in the treatment of ruptured AAA in hemodynamically unstable patients.

  3. Human HLTF mediates postreplication repair by its HIRAN domain-dependent replication fork remodelling

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

    Achar, Yathish Jagadheesh; Balogh, David; Neculai, Dante; Juhasz, Szilvia; Morocz, Monika; Gali, Himabindu; Dhe-Paganon, Sirano; Venclovas, Česlovas; Haracska, Lajos

    2015-09-08

    Defects in the ability to respond properly to an unrepaired DNA lesion blocking replication promote genomic instability and cancer. Human HLTF, implicated in error-free replication of damaged DNA and tumour suppression, exhibits a HIRAN domain, a RING domain, and a SWI/SNF domain facilitating DNA-binding, PCNA-polyubiquitin-ligase, and dsDNA-translocase activities, respectively. Here, we investigate the mechanism of HLTF action with emphasis on its HIRAN domain. We found that in cells HLTF promotes the filling-in of gaps left opposite damaged DNA during replication, and this postreplication repair function depends on its HIRAN domain. Our biochemical assays show that HIRAN domain mutant HLTF proteinsmore » retain their ubiquitin ligase, ATPase and dsDNA translocase activities but are impaired in binding to a model replication fork. These data and our structural study indicate that the HIRAN domain recruits HLTF to a stalled replication fork, and it also provides the direction for the movement of the dsDNA translocase motor domain for fork reversal. We suggest functional similarities between the HIRAN, the OB, the HARP2, and other domains found in certain motor proteins, which may explain why only a subset of DNA translocases can carry out fork reversal.« less

  4. [Repair of a cable as it relates to the North Pacific Acoustic Laboratory

    SciTech Connect (OSTI)

    Spindel, R.C.; Worcester, P.F.

    1998-12-31

    The ultimate limits of long-range sonar are imposed by ocean variability and the ambient sound field. Scattering from internal waves limits the temporal and spatial coherence of the received signal. Low frequency noise is dominated by shipping and ultimately, by wave-breaking processes. The resulting granularity of the noise field can be exploited for detection and localization purposes. The ultimate objective is to understand the fundamental limits to signal processing imposed by these ocean processes, to enable advanced signal processing techniques, including matched field processing and other adaptive array processing methods, to capitalize on the three-dimensional character of the sound and noise fields. The objective of this research is to understand the basic physics of low frequency, broadband propagation and the effects of environmental variability on signal stability and coherence. In particular, it focuses on 3-D wave front coherence (horizontal, vertical, and temporal), on the details of signal energy redistribution through mode scattering, on signal and noise variability on ocean-basin scales, and on environmental processes such as internal waves that most affect long-range coherence.

  5. Repair of radiation-induced heat-labile sites is independent of DNA-PKcs, XRCC1 or PARP

    SciTech Connect (OSTI)

    Stenerlw, Bo; Karlsson, Karin H.; Radulescu, Irina; Rydberg, Bjorn; Stenerlow, Bo

    2008-04-29

    Ionizing radiation induces a variety of different DNA lesions: in addition to the most critical DNA damage, the DSB, numerous base alterations, SSBs and other modifications of the DNA double-helix are formed. When several non-DSB lesions are clustered within a short distance along DNA, or close to a DSB, they may interfere with the repair of DSBs and affect the measurement of DSB induction and repair. We have previously shown that a substantial fraction of DSBs measured by pulsed-field gel electrophoresis (PFGE) are in fact due to heat-labile sites (HLS) within clustered lesions, thus reflecting an artifact of preparation of genomic DNA at elevated temperature. To further characterize the influence of HLS on DSB induction and repair, four human cell lines (GM5758, GM7166, M059K, U-1810) with apparently normal DSB rejoining were tested for bi-phasic rejoining after gamma irradiation. When heat-released DSBs were excluded from the measurements the fraction of fast rejoining decreased to less than 50% of the total. However, neither the half-times of the fast (t{sub 1/2} = 7-8 min) or slow (t{sub 1/2} = 2.5 h) DSB rejoining were changed significantly. At t=0 the heat-released DSBs accounted for almost 40% of the DSBs, corresponding to 10 extra DSB/cell/Gy in the initial DSB yield. These heat-released DSBs were repaired within 60-90 min in all tested cells, including M059K cells treated with wortmannin or DNA-PKcs defect M059J cells. Furthermore, cells lacking XRCC1 or Poly(ADP-ribose) polymerase-1 (PARP-1) rejoined both total DSBs and heat-released DSBs similar to normal cells. In summary, the presence of heat-labile sites have a substantial impact on DSB induction yields and DSB rejoining rates measured by pulsed-field gel electrophoresis, and HLS repair is independent of DNA-PKcs, XRCC1 and PARP.

  6. Sensitivity to methylmercury toxicity is enhanced in oxoguanine glycosylase 1 knockout murine embryonic fibroblasts and is dependent on cellular proliferation capacity

    SciTech Connect (OSTI)

    Ondovcik, Stephanie L.; Tamblyn, Laura; McPherson, John Peter; Wells, Peter G.

    2013-07-01

    Methylmercury (MeHg) is a persistent environmental contaminant with potent neurotoxic action for which the underlying molecular mechanisms remain to be conclusively delineated. Our objectives herein were twofold: first, to corroborate our previous findings of an increased sensitivity of spontaneously-immortalized oxoguanine glycosylase 1-null (Ogg1{sup ?/?}) murine embryonic fibroblasts (MEFs) to MeHg through generation of Simian virus 40 (SV40) large T antigen-immortalized wild-type and Ogg1{sup ?/?} MEFs; and second, to determine whether MeHg toxicity is proliferation-dependent. As with the spontaneously-immortalized cells used previously, the SV40 large T antigen-immortalized cells exhibited similar tendencies to undergo MeHg-initiated cell cycle arrest, with increased sensitivity in the Ogg1{sup ?/?} MEFs as measured by clonogenic survival and DNA damage. Compared to exponentially growing cells, those seeded at a higher density exhibited compromised proliferation, which proved protective against MeHg-mediated cell cycle arrest and induction of DNA double strand breaks (DSBs), measured by phosphorylation of the core histone H2A variant (H2AX) on serine 139 (?H2AX), and by its functional confirmation by micronucleus assessment. This enhanced sensitivity of Ogg1{sup ?/?} MEFs to MeHg toxicity using discrete SV40 immortalization corroborates our previous studies, and suggests a novel role for OGG1 in minimizing MeHg-initiated DNA lesions that trigger replication-associated DSBs. Furthermore, proliferative capacity may determine MeHg toxicity in vivo and in utero. Accordingly, variations in cellular proliferative capacity and interindividual variability in repair activity may modulate the risk of toxicological consequences following MeHg exposure. - Highlights: SV40 large T antigen-immortalized Ogg1{sup ?/?} cells are more sensitive to MeHg. Sensitivity to MeHg is dependent on cellular proliferation capacity. OGG1 maintains genomic integrity following Me

  7. Identification of limiting case between DBA and SBDBA (CL break area sensitivity): A new model for the boron injection system

    SciTech Connect (OSTI)

    Gonzalez Gonzalez, R.; Petruzzi, A.; D'Auria, F.; Mazzantini, O.

    2012-07-01

    Atucha-2 is a Siemens-designed PHWR reactor under construction in the Republic of Argentina. Its geometrical complexity and (e.g., oblique Control Rods, Positive Void coefficient) required a developed and validated complex three dimensional (3D) neutron kinetics (NK) coupled thermal hydraulic (TH) model. Reactor shut-down is obtained by oblique CRs and, during accidental conditions, by an emergency shut-down system (JDJ) injecting a highly concentrated boron solution (boron clouds) in the moderator tank, the boron clouds reconstruction is obtained using a CFD (CFX) code calculation. A complete LBLOCA calculation implies the application of the RELAP5-3D{sup C} system code. Within the framework of the third Agreement 'NA-SA - Univ. of Pisa' a new RELAP5-3D control system for the boron injection system was developed and implemented in the validated coupled RELAP5-3D/NESTLE model of the Atucha 2 NPP. The aim of this activity is to find out the limiting case (maximum break area size) for the Peak Cladding Temperature for LOCAs under fixed boundary conditions. (authors)

  8. A fair compromise to break the climate impasse. A major economies forum approach to emissions reductions budgeting

    SciTech Connect (OSTI)

    Grasso, Marco; J. Roberts, Timmons

    2013-04-15

    Key messages of the study are: Given the stalemate in U.N. climate negotiations, the best arena to strike a workable deal is among the members the Major Economies Forum on Energy and Climate (MEF); The 13 MEF members—including the EU-27 (but not double-counting the four EU countries that are also individual members of the MEF)—account for 81.3 percent of all global emissions; This proposal devises a fair compromise to break the impasse to develop a science-based approach for fairly sharing the carbon budget in order to have a 75 percent chance of avoiding dangerous climate change; To increase the likelihood of a future climate agreement, carbon accounting must shift from production-based inventories to consumption-based ones; The shares of a carbon budget to stay below 2 deg C through 2050 are calculated by cumulative emissions since 1990, i.e. according to a short-horizon polluter pays principle, and national capability (income), and allocated to MEF members through emission rights. This proposed fair compromise addresses key concerns of major emitters; According to this accounting, no countries have negative carbon budgets, there is substantial time for greening major developing economies, and some developed countries need to institute very rapid reductions in emissions; and, To provide a 'green ladder' to developing countries and to ensure a fair global deal, it will be crucial to agree how to extend sufficient and predictable financial support and the rapid transfer of technology.

  9. Dynamical instability of white dwarfs and breaking of spherical symmetry under the presence of extreme magnetic fields

    SciTech Connect (OSTI)

    Coelho, J. G.; Cceres, D. L.; Rueda, J. A.; Ruffini, R. [Dipartimento di Fisica and ICRA, Sapienza Universit di Roma, P.le Aldo Moro 5, I-00185 Rome (Italy); Marinho, R. M.; Malheiro, M. [Departamento de Fsica, Instituto Tecnolgico de Aeronutica, ITA, So Jos dos Campos, 12228-900 SP (Brazil); Negreiros, R., E-mail: jaziel.coelho@icranet.org, E-mail: jorge.rueda@icra.it, E-mail: m.malheiro@ita.br [Instituto de Fsica, Universidade Federal Fluminense, UFF, Niteri, 24210-346 RJ (Brazil)

    2014-10-10

    Massive, highly magnetized white dwarfs with fields up to 10{sup 9} G have been observed and theoretically used for the description of a variety of astrophysical phenomena. Ultramagnetized white dwarfs with uniform interior fields up to 10{sup 18} G have been recently purported to obey a new maximum mass limit, M {sub max} ? 2.58 M {sub ?}, which largely overcomes the traditional Chandrasekhar value, M {sub Ch} ? 1.44 M {sub ?}. Such a larger limit would make these astrophysical objects viable candidates for the explanation of the superluminous population of Type Ia supernovae. We show that several macro and micro physical aspects such as gravitational, dynamical stability, breaking of spherical symmetry, general relativity, inverse ? decay, and pycnonuclear fusion reactions are of most relevance for the self-consistent description of the structure and assessment of stability of these objects. It is shown in this work that the first family of magnetized white dwarfs indeed satisfy all the criteria of stability, while the ultramagnetized white dwarfs are very unlikely to exist in nature since they violate minimal requests of stability. Therefore, the canonical Chandrasekhar mass limit of white dwarfs still has to be applied.

  10. TRAC-PF1/MOD1 independent assessment: Semiscale Mod-2A intermediate break test S-IB-3

    SciTech Connect (OSTI)

    Kmetyk, L N

    1986-02-01

    The TRAC-PF1/MOD1 independent assessment project at Sandia National Laboratories is part of an overall effort funded by the NRC to determine the ability of various system codes to predict the detailed thermal/hydraulic response of light water reactors during accident and off-normal conditions. The TRAC code is being assessed at SNLA against test data from various integral and separate effects test facilities. As part of this assessment matrix, an intermediate break test (S-IB-3), performed at the Semiscale Mod-2A facility, has been analyzed. Using an input model with a 3-D VESSEL component, the vessel and downcomer inventories during 3-IB-3 were generally well predicted, but the core heatup was underpredicted compared to data. An equivalent calculation with an all 1-D input model ran about twice as fast as our basecase analysis using a 3-D VESSEL in the input model, but the results of the two calculations diverged significantly for many parameters of interest, with the 3-D VESSEL model results in better agreement with data. 22 refs., 100 figs.

  11. Design, build, develop and test a fieldworthy spiral tool and packer for casing repair

    SciTech Connect (OSTI)

    Koster, C.

    1993-01-01

    A new method for sealing casing is under research and development by Nu-Bore Systems. The method involves internally lining a section of the wellbore with a multi-layer spiral wrapping of a high strength, corrosion resistant metal interleaved with a high bond strength, resilient epoxy. The high strength metal is preferably a copper based alloy hardened to a very high strength in order to resist the internal and external pressures of downhole environments. The epoxy adhesive formulation is one that forms a bond between the steel inner wall of the casing and copper alloy strip. The copper alloy strip spiral wraps are interleaved with epoxy, and the whole system provides a high level of outward directed spring force and, thus, resists both internal and externally directed forces. In this report, the cost savings to the nation's energy program was estimated to be in the range of hundreds of millions of dollars per year, and the method was judged technically feasible once certain well defined engineering obstacles are Overcome. The objective of this program is to develop a joint between packer segments that is easily assembled before lowering downhole and easily disassembled after the sealing job is done. In addition, this tool joint must expand uniformly as though it were a part of the rubber and must not fail under the relatively high pressure of the epoxy cure cycle. The overall goal of the work was to design, build, develop, and test a spiral tool and packer into a single universal tool that can repair casings with diameters varying from 4.5 to 7 inches.

  12. Identification of Intrinsic Order and Disorder in the DNA Repair Protein XPA

    SciTech Connect (OSTI)

    Iakoucheva, Lilia M.; Kimzey, Amy L.; Masselon, Christophe D.; Bruce, James E.; Garner, Ethan C.; Brown, Celeste J.; Dunker, A. K.; Smith, Richard D.; Ackerman, Eric J.

    2001-03-01

    The damage recognition protein XPA is required to recognize a wide variety of bulky lesions during nucleotide excision repair (NER). Independent NMR solution structures of a human XPA protein (hXPA) fragment comprising approximately one-third of the full-length protein, the minimal DNA-binding domain (MBD), revealed that ~30% of the molecule was structurally disordered. To better characterize structural features of XPA, we performed time-resolved trypsin proteolysis on active, full-length recombinant Xenopus XPA protein (xXPA). The resulting proteolytic fragments were analyzed by electrospray ionization interface coupled to a Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry, SDS-polyacrylamide gel electrophoresis (PAGE), and selected N-terminal sequence determinations. The mass spectrum of the full-length xXPA was consistent with the predicted sequence, 30922.02 vs. 30922.45 Da; respectively. Moreover, the mass spectrometric data allowed the assignment of multiple xXPA fragments not resolvable by SDS PAGE. Full-length xXPA exhibited aberrant mobility on SDS-PAGE with an apparent MW of ~40 kDa. To test predictions that a Glu-rich region (E70-E76) or other local regions of high charge were responsible for this ~40% aberrant SDS-PAGE mobility, the MW's of partial proteolytic fragments from ~5 to 25 kDa precisely determined by ESI-FTICR MS were correlated with their gel positions. Surprisingly, all tested partial tryptic fragments within this size-range exhibited 10-42% divergence between calculated MW and that estimated by SDS-PAGE, thus indicating the origin of anomalous migration of XPA is not localized. The computer program Predictor of Natural Disordered Regions (PONDR) correctly identified several regions of xXPA either sensitive or resistant to partial proteolysis, thereby indicating that disorder in XPA shares sequence features with other well-characterized intrinsically unstructured proteins.

  13. Large Diameter Limbs for Dilated Common Iliac Arteries in Endovascular Aneurysm Repair. Is It Safe?

    SciTech Connect (OSTI)

    Malagari, Katerina Brountzos, Elias; Gougoulakis, Alexandros; Papathanasiou, Matilda; Alexopoulou, Efthymia; Mastorakou, Renata; Kelekis, Dimitris

    2004-09-15

    In this prospective study we examined whether dilated common iliac arteries (CIAs) can provide a safe distal seal in endovascular aneurysm repair (EVAR) with the use of bifurcated stent grafts with large diameter limbs. Sixteen patients with 26 dilated CIAs with a diameter of {>=}6 mm who were offered EVAR using stent grafts with large diameter limbs were included in the study (Group A). Forty-two patients who also underwent EVAR without iliac dilatation, matched for age, sex and surgical risk were used for comparison (controls-Group B). In group A mean CIA diameter was 18.2 mm (16-28) and mean abdominal aortic aneurysm (AAA) diameter was 6.87 {+-} 1.05 cm; mean age was 77.2 {+-} 4.8 yrs (67-81). Mean follow-up was 33.6 months (2.8 yrs). CIA diameter changes and development of endoleaks were assessed by CT angiography (CTA). Overall iliac dilatation was present in 16/58 of our patients (27.6%). In 10 patients dilatation was bilateral (17.3%). Partial or complete flow to the internal iliac artery (IIA) territories was preserved in all patients post-EVAR. On follow-up, stable caliber of the dilated CIAs was observed in 21 patients (84%), enlargement of 1mm in 3 (16%), and failure of the distal attachment in 1 (6.2%). Compared to the control group there was no statistical significance in the incidence of complications. Dilated common iliac arteries provide a safe distal seal in patients who have undergone EVAR, thus obviating the need for additional endovascular procedures and sparing flow in the IIA vascular bed.

  14. Breaking Barriers Wildlife Refreshment

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

    Barriers Wildlife Refreshment Walker becomes first black battalion commander. NSTec Aviation Safety Officer, RSL team honored by DOE. NNSS helping wildlife with new watering holes. See pages 8. See page 4. NSTec and UNLV Bring Technology Community Together at PDV Workshop In June 2014, National Security Technologies (NSTec) and University Nevada, Las Vegas (UNLV) co- hosted a Photon Doppler Velocimetry (PDV) Workshop at the UNLV Science and Engineering Building (SEB). More than 125 attendees

  15. Spontaneous soliton symmetry breaking in two-dimensional coupled Bose-Einstein condensates supported by optical lattices

    SciTech Connect (OSTI)

    Gubeskys, Arthur; Malomed, Boris A.

    2007-10-15

    Models of two-dimensional (2D) traps, with double-well structure in the third direction, for Bose-Einstein condensates are introduced with attractive or repulsive interactions between atoms. The models are based on systems of linearly coupled 2D Gross-Pitaevskii equations, where the coupling accounts for tunneling between the wells. Each well carries an optical lattice (OL) (stable 2D solitons cannot exist without OLs). The linear coupling splits each finite band gap in the spectrum of the single-component model into two subgaps. The main subject of the work is spontaneous symmetry breaking (SSB) in two-component 2D solitons and localized vortices (SSB was not considered before in 2D settings). Using variational approximation (VA) and numerical methods, we demonstrate that, in a system with attraction or repulsion, SSB occurs in families of symmetric or antisymmetric solitons (or vortices), respectively. The corresponding bifurcation destabilizes the original solution branch and gives rise to a stable branch of asymmetric solitons or vortices. The VA provides for an accurate description of the emerging branch of asymmetric solitons. In the model with attraction, all stable branches eventually terminate due to the onset of collapse. Stable asymmetric solitons in higher finite band gaps and vortices with a multiple topological charge are found too. The models also give rise to first examples of embedded solitons and embedded vortices (the states located inside Bloch bands) in two dimensions. In the linearly coupled system with opposite signs of the nonlinearity in the two cores, two distinct types of stable solitons and vortices are found, dominated by either the self-attractive component or the self-repulsive one. In the system with a mismatch between the two OLs, a pseudobifurcation is found: when the mismatch attains its largest value ({pi}), the bifurcation does not happen, as branches of different solutions asymptotically approach each other, but fail to merge.

  16. DIFFUSE FAR-UV LINE EMISSION FROM THE LOW-REDSHIFT LYMAN BREAK GALAXY ANALOG KISSR242

    SciTech Connect (OSTI)

    France, Kevin; Nell, Nicholas; Green, James C. [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309 (United States); Leitherer, Claus, E-mail: kevin.france@colorado.ed [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)

    2010-10-10

    We present new ultraviolet (UV) observations of the luminous compact blue galaxy KISSR242, obtained with the Hubble Space Telescope-Cosmic Origins Spectrograph (HST-COS). We identify multiple resolved sub-arcsecond near-UV sources within the COS aperture. The far-UV spectroscopic data show strong outflow absorption lines, consistent with feedback processes related to an episode of massive star formation. O I, C II, and Si II-Si IV are observed with a mean outflow velocity (v {sub out}) = -60 km s{sup -1}. We also detect faint fine-structure emission lines of singly ionized silicon for the first time in a low-redshift starburst galaxy. These emissions have been seen previously in deep Lyman break galaxy surveys at z {approx} 3. The Si II* lines are at the galaxy rest velocity, and they exhibit a quantitatively different line profile from the absorption features. These lines have a width of {approx}75 km s{sup -1}, too broad for point-like emission sources such as the H II regions surrounding individual star clusters. The size of the Si II* emitting region is estimated to be {approx}250 pc. We discuss the possibility of this emission arising in overlapping super star cluster H II regions, but find this explanation to be unlikely in light of existing far-UV observations of local star-forming galaxies. We suggest that the observed Si II* emission originates in a diffuse warm halo populated by interstellar gas driven out by intense star formation and/or accreted during a recent interaction that may be fueling the present starburst episode in KISSR242.

  17. A LOW ESCAPE FRACTION OF IONIZING PHOTONS OF L > L* LYMAN BREAK GALAXIES AT z = 3.3

    SciTech Connect (OSTI)

    Boutsia, K.; Grazian, A.; Giallongo, E.; Fontana, A.; Pentericci, L.; Castellano, M.; Fiore, F.; Gallozzi, S.; Testa, V.; Paris, D.; Santini, P.; Zamorani, G.; Mignoli, M.; Vanzella, E.; Lilly, S. J.

    2011-07-20

    We present an upper limit for the relative escape fraction (f{sup rel}{sub esc}) of ionizing radiation at z {approx} 3.3 using a sample of 11 Lyman break galaxies (LBGs) with deep imaging in the U band obtained with the Large Binocular Camera, mounted on the prime focus of the Large Binocular Telescope. We selected 11 LBGs with secure redshifts in the range 3.27 < z < 3.35, from three independent fields. We stacked the images of our sources in the R and U bands, which correspond to an effective rest-frame wavelength of 1500 A and 900 A, respectively, obtaining a limit in the U band image of {>=}30.7 mag (AB) at 1{sigma}. We derive a 1{sigma} upper limit of f{sup rel}{sub esc} {approx} 5%, which is one of the lowest values found in the literature so far at z {approx} 3.3. Assuming that the upper limit for the escape fraction that we derived from our sample holds for all galaxies at this redshift, the hydrogen ionization rate that we obtain ({Gamma}{sub -12} < 0.3 s{sup -1}) is not enough to keep the intergalactic medium ionized and a substantial contribution to the UV background by faint active galactic nuclei is required. Since our sample is clearly still limited in size, larger z {approx} 3 LBG samples at similar or even greater depths are necessary to confirm these results on a more firm statistical basis.

  18. Evaluation of a main steam line break with induced, multiple tube ruptures: A comparison of NUREG 1477 (Draft) and transient methodologies Palo Verde Nuclear Generating Station

    SciTech Connect (OSTI)

    Parrish, K.R.

    1995-09-01

    This paper presents the approach taken to analyze the radiological consequences of a postulated main steam line break event, with one or more tube ruptures, for the Palo Verde Nuclear Generating Station. The analysis was required to support the restart of PVNGS Unit 2 following the steam generator tube rupture event on March 14, 1993 and to justify continued operation of Units 1 and 3. During the post-event evaluation, the NRC expressed concern that Unit 2 could have been operating with degraded tubes and that similar conditions could exist in Units 1 and 3. The NRC therefore directed that a safety assessment be performed to evaluate a worst case scenario in which a non-isolable main steam line break occurs inducing one or more tube failures in the faulted steam generator. This assessment was to use the generic approach described in NUREG 1477, Voltage-Based Interim Plugging Criteria for Steam Generator Tubes - Task Group Report. An analysis based on the NUREG approach was performed but produced unacceptable results for off-site and control room thyroid doses. The NUREG methodology, however, does not account for plant thermal-hydraulic transient effects, system performance, or operator actions which could be credited to mitigate dose consequences. To deal with these issues, a more detailed analysis methodology was developed using a modified version of the Combustion Engineering Plant Analysis Code, which examines the dose consequences for a main steam line break transient with induced tube failures for a spectrum equivalent to 1 to 4 double ended guillotine U-tube breaks. By incorporating transient plant system responses and operator actions, the analysis demonstrates that the off-site and control room does consequences for a MSLBGTR can be reduced to acceptable limits. This analysis, in combination with other corrective and recovery actions, provided sufficient justification for continued operation of PVNGS Units 1 and 3, and for the subsequent restart of Unit 2.

  19. Ba{sub 6}Ge{sub 25}: low-temperature Ge-Ge bond breaking during temperature-induced structure transformation

    SciTech Connect (OSTI)

    Carrillo-Cabrera, Wilder . E-mail: carrillo@cpfs.mpg.de; Borrmann, Horst; Paschen, Silke; Baenitz, Michael; Steglich, Frank; Grin, Yuri

    2005-03-15

    In order to find the optimal conditions for sample preparation of the binary germanide Ba{sub 6}Ge{sub 25}, the germanium-rich part of the Ba-Ge phase diagram was redetermined by means of metallography, X-ray powder diffraction and differential thermal analysis. The temperature behavior of cubic Ba{sub 6}Ge{sub 25} was investigated both on polycrystalline samples and single crystals. The temperature dependence of the lattice parameter exhibits two anomalies at about 180 and 230K, respectively, which are caused by a structure transformation in two steps with hysteresis. Powder (T=10-295K) and single-crystal (T=95-295K) X-ray diffraction studies confirm that the symmetry of Ba{sub 6}Ge{sub 25} (space group P4{sub 1}32) remains unchanged within the entire temperature range. A reconstructive behavior of the structural transformation is observed, involving Ge-Ge bond breaking and barium cation displacements. Some Ge4 type atoms ({approx}28%) are so significantly displaced during cooling that Ge4-Ge6 bonds break and new three-bonded (3b)Ge{sup -} species (electron acceptors) are formed. Consequently, the number of charge carriers is reduced, affecting the physical properties. The reversible bond breaking involved in this process is a typical characteristic of a solid-state chemical reac0010ti.

  20. Encapsulation of Protonated Diamines in a Water-Soluble Chiral, Supramolecular Assembly Allows for Measurement of Hydrogen-Bond Breaking Followed by Nitrogen Inversion/Rotation (NIR)

    SciTech Connect (OSTI)

    Meux, Susan C.; Pluth, Michael D.; Bergman, Robert G.; Raymond, Kenneth N.

    2007-09-19

    Amine nitrogen inversion, difficult to observe in aqueous solution, is followed in a chiral, supramolecular host molecule with purely-rotational T-symmetry that reduces the local symmetry of encapsulated monoprotonated diamines and enables the observation and quantification of {Delta}G{double_dagger} for the combined hydrogen-bond breaking and nitrogen inversion rotation (NIR) process. Free energies of activation for the combined hydrogen-bond breaking and NIR process inside of the chiral assembly were determined by the NMR coalescence method. Activation parameters for ejection of the protonated amines from the assembly confirm that the NIR process responsible for the coalescence behavior occurs inside of the assembly rather than by a guest ejection/NIR/re-encapsulation mechanism. For one of the diamines, N,N,N{prime},N{prime}-tetramethylethylenediamine (TMEDA), the relative energy barriers for the hydrogen-bond breaking and NIR process were calculated at the G3(MP2)//B3LYP/6-31++G(d,p) level of theory, and these agreed well with the experimental data.

  1. Environmental Assessment and Finding of No Significant Impact: Pond B Dam Repair Project at the Savannah River Site

    SciTech Connect (OSTI)

    N /A

    1999-09-27

    The Department of Energy (DOE) has prepared an environmental assessment (EA) (DOE/EA-1285) for the proposed repair of the Pond B dam at the Savannah River Site (SRS), located near Aiken, South Carolina. Based on the analyses in the EA, DOE has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 (NEPA). Therefore, the preparation of an environmental impact statement (EIS) is not required, and DOE is issuing this Finding of No Significant Impact (FONSI) and Floodplain Statement of Findings.

  2. New Technologies for Repairing Aging Cables in Nuclear Power Plants: M3LW-14OR0404015 Cable Rejuvenation Report

    SciTech Connect (OSTI)

    Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.; Roberts, John A.

    2014-09-08

    The goal of this project is to conceptually demonstrate techniques to repair cables that have degraded through subjection to long-term thermal and radiation exposure in nuclear power plants. In fiscal year 2014 (FY14) we focused on commercially available ethylene-propylene rubber (EPR) as the relevant test material, isolated a high surface area form of the EPR material to facilitate chemical treatment screening and charaterization, and measured chemical changes in the material due to aging and treatment using Fourier Transfrom Infrared (FTIR) spectroscopy.

  3. Evaluating the integrity of the reinforced concrete structure repaired by epoxy injection using simulated transfer function of impact-echo response

    SciTech Connect (OSTI)

    Cheng, Chia-Chi; Yu, Chih-peng; Wu, Jiunn-Hong; Hsu, Keng-Tsan; Ke, Ying-Tsu

    2014-02-18

    Cracks and honeycombs are often found inside reinforced concrete (RC) structure caused by excessive external force, or improper casting of concrete. The repairing method usually involves epoxy injection. The impact-echo method, which is a sensitive for detecting of the interior voids, may not be applicable to assess the integrity of the repaired member as both air and epoxy are less in acoustic impedances. In this study, the repaired RC structure was evaluated by the simulated transfer function of the IE displacement waveform where the R-wave displacement waveform is used as a base of a simulated force-time function. The effect of different thickness of the epoxy layer to the amplitude corresponding to the interface is studied by testing on specimen containing repaired naturally delaminated cracks with crack widths about 1 mm, 3 mm and 5 mm. The impact-echo responses were compared with the drilling cores at the test positions. The results showed the cracks were not fully filled with epoxy when the peak amplitude corresponding to the interface dropped less than 20%. The peak corresponding to the thicker epoxy layer tends to be larger in amplitude. A field study was also performed on a column damaged by earthquake before and after repairing.

  4. Steam Line Break and Station Blackout Transients for Proliferation-Resistant Hexagonal Tight Lattice Boiling Water Reactor

    SciTech Connect (OSTI)

    Rohatgi, Upendra S. [Brookhaven National Laboratory (United States); Jo, Jae H. [Brookhaven National Laboratory (United States); Chung, Bub Dong [Brookhaven National Laboratory (United States); Takahashi, Hiroshi [Brookhaven National Laboratory (United States); Downar, Thomas J. [Purdue University (United States)

    2004-01-15

    for a tight pitch lattice core: the station blackout and the main-steam-line-break events. The results of the analyses indicate that the HCBWR system will be safely brought to the shutdown condition for these transients.

  5. CHARGE-IMBALANCE RELAXATION IN THE PRESENCE OF A PAIR-BREAKING INTERACTION IN SUPERCONDUCTING AlEr FILMS

    SciTech Connect (OSTI)

    Lemberger, T.R.; Clarke, J.

    1980-07-01

    The charge-imbalance relaxation rate, 1/F*{sub T{sub Q*}}, has been measured in dirty superconducting AlEr films in which Er is a pair-breaking magnetic impurity that induces charge relaxation through elastic exchange scattering. Measurements were made in the range 0.1 {approx}< {Delta}(T)/k{sub B}T{sub c} {approx}< 1.4 for Er concentrations varying from 21 to 1660 at. ppm that produced estimated exchange scattering rates, {tau}{sub S}{sup -1}, from about 10{sup 9} sec{sup -1} to 5 x 10{sup 10} sec{sup -1}. Measured values of 1/F*{sub T{sub Q*}} were in good agreement with the Schmid-Schoen expression, 1/F*{sub T{sub Q*}}=({pi}{Delta}/4k{sub B}T{sub c}{tau}{sub E}) x (1+2{tau}{sub E}/{tau}{sub S}){sup 1/2}, for {Delta}/k{sub B}T{sub c} {approx}< 0.8, where {tau}{sub E}{sup -1} is the electron-phonon scattering rate estimated from the measured transition temperature. For larger values of {Delta}/k{sub B}T{sub c}, the relaxation rate increased less rapidly with {Delta}. The appropriate Boltzmann equation was solved on a computer to obtain values for 1/F*{sub T{sub Q*}} in the range 0.5 {approx}< T/T{sub c} {approx}< 0.999999. The computed values of 1/F*{sub T{sub Q*}} agreed with several analytic expressions valid for {Delta}/k{sub B}T{sub c} << 1, but not with the experimental data: The computed curves increased more rapidly than linearly with {Delta}/k{sub B}T{sub c} near T{sub c}, and the shape of the 1/F*{sub T{sub Q*}} vs {Delta}/k{sub B}T{sub c} curves was qualitatively different. This discrepancy suggests that either the generally accepted expression for exchange charge relaxation is incorrect, or that the Boltzmann equation is inappropriate for these calculations.

  6. PHYSICAL PROPERTIES, STAR FORMATION, AND ACTIVE GALACTIC NUCLEUS ACTIVITY IN BALMER BREAK GALAXIES AT 0 < z < 1

    SciTech Connect (OSTI)

    Diaz Tello, J.; Donzelli, C.; Padilla, N.; Fujishiro, N.; Yoshikawa, T.; Hanami, H.; Hatsukade, B.

    2013-07-01

    We present a spectroscopic study with the derivation of the physical properties of 37 Balmer break galaxies, which have the necessary lines to locate them in star-forming-active galactic nuclei (AGNs) diagnostic diagrams. These galaxies span a redshift range from 0.045 to 0.93 and are somewhat less massive than similar samples of previous works. The studied sample has multiwavelength photometric data coverage from the ultraviolet to mid-infrared (MIR) Spitzer bands. We investigate the connection between star formation and AGN activity via optical, mass-excitation (MEx), and MIR diagnostic diagrams. Through optical diagrams, 31 (84%) star-forming galaxies, two (5%) composite galaxies, and three (8%) AGNs were classified, whereas from the MEx diagram only one galaxy was classified as AGN. A total of 19 galaxies have photometry available in all the IRAC/Spitzer bands. Of these, three AGN candidates were not classified as AGN in the optical diagrams, suggesting they are dusty/obscured AGNs, or that nuclear star formation has diluted their contributions. By fitting the spectral energy distribution of the galaxies, we derived the stellar masses, dust reddening E(B - V), ages, and UV star formation rates (SFRs). Furthermore, the relationship between SFR surface density ({Sigma}{sub SFR}) and stellar mass surface density per time unit ({Sigma}{sub M{sub */{tau}}}) as a function of redshift was investigated using the [O II] {lambda}3727, 3729, H{alpha} {lambda}6563 luminosities, which revealed that both quantities are larger for higher redshift galaxies. We also studied the SFR and specific SFR (SSFR) versus stellar mass and color relations, with the more massive galaxies having higher SFR values but lower SSFR values than less massive galaxies. These results are consistent with previous ones showing that, at a given mass, high-redshift galaxies have on average larger SFR and SSFR values than low-redshift galaxies. Finally, bluer galaxies have larger SSFR values than redder

  7. FABRICATION AND REPAIR OF ION SOURCE COMPONENTS IN THE 80 keV NEUTRAL BEAM LINES FOR DIII-D

    SciTech Connect (OSTI)

    GRUNLOH,H.J; BUSATH,J.L; CALLIS,R.W; CHIU,H.K; DiMARTINO,M; HONG,R; KLASEN,R; MOELLER,C.P; ROBINSON,J.I; STRECKERT,H.H; TAO,R; TRESTER,P.W

    2003-10-01

    OAK-B135 After 8 years of operation, leaks began to develop in critical components of the ion sources of the 80 keV neutral beam lines in DIII-D. Operational adjustments were made that seemed to remedy the problems, but five years later leaks began occurring again, this time with greater frequency. Failures occurred in the stainless steel bellows and molybdenum rails of the grid rail modules as well as in the Langmuir probes. Failure analyses identified several root causes of the leaks and operational adjustments were again made to mitigate the problems, but the rash of failures depleted the program's supply of spare grid rail modules and probes and removed one of the ion sources from regular operation. Fifteen years after their original fabrication, the ion source components were no longer commercially available. In 2001, a program was initiated to fabricate new grid rail modules, including new molybdenum grid rails, bellows, and stainless steel grid rail holders, as well as new Langmuir probes. In parallel, components removed from service due to leaks were to be repaired with new rails and bellows and returned to service. An overview of the root causes of the service failures is offered, details of the repair processes are described, and a summary and evaluation of the fabrication procedures for the new molybdenum rails, grid modules, and Langmuir probes are given.

  8. Genome-Wide Identification and 3D Modeling of Proteins involved in DNA Damage Recognition and Repair (Final Report)

    SciTech Connect (OSTI)

    Ruben A. Abagyan, PhD

    2004-04-15

    OAK-B135 DNA Damage Recognition and Repair (DDR and R) proteins play a critical role in cellular responses to low-dose radiation and are associated with cancer. the authors have performed a systematic, genome-wide computational analysis of genomic data for human genes involved in the DDR and R process. The significant achievements of this project include: (1) Construction of the computational pipeline for searching DDR and R genes, building and validation of 3D models of proteins involved in DDR and R; (2) Functional and structural annotation of the 3D models and generation of comprehensive lists of suggested knock-out mutations; (3) Important improvement of macromolecular docking technology and its application to predict the DNA-Protein complex conformation; (4) Development of a new algorithm for improved analysis of high-density oligonucleotide arrays for gene expression profiling; (5) Construction and maintenance of the DNA Damage Recognition and Repair Database; and (6) Producing 14 research papers (10 published and 4 in preparation).

  9. Genome-Wide Identification and 3D Modeling of Proteins involved in DNA Damage Recognition and Repair (Final Report)

    SciTech Connect (OSTI)

    Abagyan, Ruben; An, Jianghong

    2005-08-12

    DNA Damage Recognition and Repair (DDR&R) proteins play a critical role in cellular responses to low-dose radiation and are associated with cancer. We have performed a systematic, genome-wide computational analysis of genomic data for human genes involved in the DDR&R process. The significant achievements of this project include: 1) Construction of the computational pipeline for searching DDR&R genes, building and validation of 3D models of proteins involved in DDR&R; 2) Functional and structural annotation of the 3D models and generation of comprehensive lists of suggested knock-out mutations; and the development of a method to predict the effects of mutations. Large scale testing of technology to identify novel small binding pockets in protein structures leading to new DDRR inhibitor strategies 3) Improvements of macromolecular docking technology (see the CAPRI 1-3 and 4-5 results) 4) Development of a new algorithm for improved analysis of high-density oligonucleotide arrays for gene expression profiling; 5) Construction and maintenance of the DNA Damage Recognition and Repair Database; 6) Producing 15 research papers (12 published and 3 in preparation).

  10. Polychlorinated biphenyl quinone induces oxidative DNA damage and repair responses: The activations of NHEJ, BER and NER via ATM-p53 signaling axis

    SciTech Connect (OSTI)

    Dong, Hui; Shi, Qiong; Song, Xiufang; Fu, Juanli; Hu, Lihua; Xu, Demei; Su, Chuanyang; Xia, Xiaomin; Song, Erqun; Song, Yang

    2015-07-01

    Our previous studies demonstrated that polychlorinated biphenyl (PCB) quinone induced oxidative DNA damage in HepG2 cells. To promote genomic integrity, DNA damage response (DDR) coordinates cell-cycle transitions, DNA repair and apoptosis. PCB quinone-induced cell cycle arrest and apoptosis have been documented, however, whether PCB quinone insult induce DNA repair signaling is still unknown. In this study, we identified the activation of DDR and corresponding signaling events in HepG2 cells upon the exposure to a synthetic PCB quinone, PCB29-pQ. Our data illustrated that PCB29-pQ induces the phosphorylation of p53, which was mediated by ataxia telangiectasia mutated (ATM) protein kinase. The observed phosphorylated histone H2AX (γ-H2AX) foci and the elevation of 8-hydroxy-2′-deoxyguanosine (8-OHdG) indicated that DDR was stimulated by PCB29-pQ treatment. Additionally, we found PCB29-pQ activates non-homologous end joining (NHEJ), base excision repair (BER) and nucleotide excision repair (NER) signalings. However, these repair pathways are not error-free processes and aberrant repair of DNA damage may cause the potential risk of carcinogenesis and mutagenesis. - Highlights: • Polychlorinated biphenyl quinone induces oxidative DNA damage in HepG2 cells. • The elevation of γ-H2AX and 8-OHdG indicates the activation of DNA damage response. • ATM-p53 signaling acts as the DNA damage sensor and effector. • Polychlorinated biphenyl quinone activates NHEJ, BER and NER signalings.

  11. Synthesis of DNA

    DOE Patents [OSTI]

    Mariella, Jr., Raymond P.

    2008-11-18

    A method of synthesizing a desired double-stranded DNA of a predetermined length and of a predetermined sequence. Preselected sequence segments that will complete the desired double-stranded DNA are determined. Preselected segment sequences of DNA that will be used to complete the desired double-stranded DNA are provided. The preselected segment sequences of DNA are assembled to produce the desired double-stranded DNA.

  12. SPES-2, AP600 intergral system test S01007 2 inch CL to core make-up tank pressure balance line break

    SciTech Connect (OSTI)

    Bacchiani, M.; Medich, C.; Rigamonti, M.

    1995-09-01

    The SPES-2 is a full height, full pressure experimental test facility reproducing the Westinghouse AP600 reactor with a scaling factor of 1/395. The experimental plant, designed and operated by SIET in Piacenza, consists of a full simulation of the AP600 primary core cooling system including all the passive and active safety systems. In 1992, Westinghouse, in cooperation with ENEL (Ente Nazionale per l` Energia Elettrica), ENEA (Enter per le numove Technlogie, l` Energia e l` Ambient), Siet (Societa Informazioni Esperienze Termoidraulich) and ANSALDO developed an experimental program to test the integrated behaviour of the AP600 passive safety systems. The SPES-2 test matrix, concluded in November 1994, has examined the AP600 passive safety system response for a range of small break LOCAs at different locations on the primary system and on the passive system lines; single steam generator tube ruptures with passive and active safety systems and a main steam line break transient to demonstrate the boration capability of passive safety systems for rapid cooldown. Each of the tests has provided detailed experimental results for verification of the capability of the analysis methods to predict the integrated passive safety system behaviour. Cold and hot shakedown tests have been performed on the facility to check the characteristics of the plant before starting the experimental campaign. The paper first presents a description of the SPES-2 test facility then the main results of S01007 test {open_quotes}2{close_quotes} Cold Leg (CL) to Core Make-up Tank (CMT) pressure balance line break{close_quotes} are reported and compared with predictions performed using RELAP5/mod3/80 obtained by ANSALDO through agreement with U.S.N.R.C. (U.S. Nuclear Regulatory Commission). The SPES-2 nodalization and all the calculations here presented were performed by ANSALDO and sponsored by ENEL as a part of pre-test predictions for SPES-2.

  13. Determination of the bias in LOFT fuel peak cladding temperature data from the blowdown phase of large-break LOCA experiments

    SciTech Connect (OSTI)

    Berta, V.T.; Hanson, R.G.; Johnsen, G.W.; Schultz, R.R.

    1993-05-01

    Data from the Loss-of-Fluid Test (LOFT) Program help quantify the margin of safety inherent in pressurized water reactors during postulated loss-of-coolant accidents (LOCAs). As early as 1979, questions arose concerning the accuracy of LOFT fuel rod cladding temperature data during several large-break LOCA experiments. This report analyzes how well externally-mounted fuel rod cladding thermocouples in LOFT accurately reflected actual cladding surface temperature during large-break LOCA experiments. In particular, the validity of the apparent core-wide fuel rod cladding quench exhibited during blowdown in LOFT Experiments L2-2 and L2-3 is studied. Also addressed is the question of whether the externally-mounted thermocouples might have influenced cladding temperature. The analysis makes use of data and information from several sources, including later, similar LOFT Experiments in which fuel centerline temperature measurements were made, experiments in other facilities, and results from a detailed FRAP-T6 model of the LOFT fuel rod. The analysis shows that there can be a significant difference (referred to as bias) between the surface-mounted thermocouple reading and the actual cladding temperature, and that the magnitude of this bias depends on the rate of heat transfer between the fuel rod cladding and coolant. The results of the analysis demonstrate clearly that a core-wide cladding quench did occur in Experiments L2-2 and L2-3. Further, it is shown that, in terms of peak cladding temperature recording during LOFT large-break LOCA experiments, the mean bias is 11.4 {plus_minus} 16.2K (20.5 {plus_minus} 29.2{degrees} F). The best-estimate value of peak cladding temperature for LOFT LP-02-6 is 1,104.8 K. The best-estimate peak cladding temperature for LOFT LP-LB-1 is 1284.0 K.

  14. Evaluation and Repair of Primary Water Stress Corrosion Cracking in Alloy 600/182 Control Rod Drive Mechanism Nozzles

    SciTech Connect (OSTI)

    Frye, Charles R.; Arey, Melvin L. Jr.; Robinson, Michael R.; Whitaker, David E.

    2002-07-01

    In February 2001, a routine visual inspection of the reactor vessel head of Oconee Nuclear Station Unit 3 identified boric acid crystals at nine of sixty-nine locations where control rod drive mechanism housings (CRDM nozzles) penetrate the head. The boric acid deposits resulted from primary coolant leaking from cracks in the nozzle attachment weld and from through-thickness cracks in the nozzle wall. A general overview of the inspection and repair process is presented and results of the metallurgical analysis are discussed in more detail. The analysis confirmed that primary water stress corrosion cracking (PWSCC) is the mechanism of failure of both the Alloy 182 weld filler material and the alloy 600 wrought base material. (authors)

  15. Repair of a Mirror Coating on a Large Optic for High Laser Damage Applications using Ion Milling and Over-Coating Methods.

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

    Field, Ella Suzanne; Bellum, John Curtis; Kletecka, Damon E.

    2016-06-01

    When an optical coating is damaged, deposited incorrectly, or is otherwise unsuitable, the conventional method to restore the optic often entails repolishing the optic surface, which can incur a large cost and long lead time. We propose three alternative options to repolishing, including (i) burying the unsuitable coating under another optical coating, (ii) using ion milling to etch the unsuitable coating completely from the optic surface, and then recoating the optic, and (iii) using ion milling to etch through a number of unsuitable layers, leaving the rest of the coating intact, and then recoating the layers that were etched. Repairsmore » were made on test optics with dielectric mirror coatings according to the above three options. The mirror coatings to be repaired were quarter wave stacks of HfO2 and SiO2 layers for high reflection at 1054 nm at 45° incidence in P-polarization. One of the coating layers was purposely deposited incorrectly as Hf metal instead of HfO2 to evaluate the ability of each repair method to restore the coating’s high laser-induced damage threshold (LIDT) of 64.0 J/cm2. Finally, the repaired coating with the highest resistance to laser-induced damage was achieved using repair method (ii) with an LIDT of 49.0 – 61.0 J/cm2.« less

  16. Mechanisms of radiation-induced gene responses

    SciTech Connect (OSTI)

    Woloschak, G.E.; Paunesku, T.

    1996-10-01

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

  17. Symmetry breaking and electrical frustration during tip-induced polarization switching in the non-polar cut of lithium niobate single crystals

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

    Ievlev, Anton; Alikin, Denis O.; Morozovska, A. N.; Varenyk, O. V.; Eliseev, E. A.; Kholkin, Andrei; Shur, Vladimir Ya.; Kalinin, Sergei V.

    2014-12-15

    Polarization switching in ferroelectric materials is governed by a delicate interplay between bulk polarization dynamics and screening processes at surfaces and domain walls. Here we explore the mechanism of tip-induced polarization switching in the non-polar cuts of uniaxial ferroelectrics. In this case, in-plane component of polarization vector switches, allowing for detailed observations of resultant domain morphologies. We observe surprising variability of resultant domain morphologies stemming from fundamental instability of formed charged domain wall and associated electric frustration. In particular, we demonstrate that controlling vertical tip position allows the polarity of the switching to be controlled. This represents very unusual formmore » of symmetry breaking where mechanical motion in vertical direction controls the lateral domain growth. The implication of these studies for ferroelectric devices and domain wall electronics are discussed.« less

  18. Multiloop integral system test (MIST): Test Group 32, SBLOCA (small-break loss-of-coolant accidents) with altered leak and HPI (high-pressure injection) configurations

    SciTech Connect (OSTI)

    Gloudemans, J.R. . Nuclear Power Div.)

    1989-07-01

    The multiloop integral system test (MIST) is part of a multiphase program started in 1983 to address small-break loss-of-coolant accidents (SBLOCAs) specific to Babcock Wilcox-designed plants. MIST is sponsored by the US Nuclear Regulatory Commission, and Babcock Wilcox Owners Group, the Electric Power Research Institute, and Babcock Wilcox. The unique features of the Babcock Wilcox design, specifically the hot leg U-bends and steam generators, prevented the use of existing integral system data or existing integral system facilities to address the thermal-hydraulic SBLOCA questions. MIST and two other supporting facilities were specifically designed and constructed for this program, and an existing facility -- the once-through integral system (OTIS) -- was also used. Data from MIST and the other facilities will be used to benchmark the adequacy of system codes, such as RELAP-5 and TRAC, for predicting abnormal plant transients. 6 refs., 143 figs., 12 tabs.

  19. Stable SUSY breaking model with O(10) eV gravitino from combined D-term gauge mediation and U(1)' mediation

    SciTech Connect (OSTI)

    Nakayama, Yu; Nakayama, Yu

    2007-12-17

    We show a calculable example of stable supersymmetry (SUSY) breaking modelswith O(10) eV gravitino mass based on the combination of D-term gauge mediationand U(1)' mediation. A potential problem of the negative mass squared for theSUSY standard model (SSM) sfermions in the D-term gauge mediation is solvedby the contribution from the U(1)' mediation. On the other hand, the splittingbetween the SSM gauginos and sfermions in the U(1)' mediation iscircumvented bythe contributions from the D-term gauge mediation. Since the U(1)' mediation doesnot introduce any new SUSY vacua, we achieve a completely stable model underthermal effects. Our model, therefore, has no cosmological difficulty.

  20. Search for Gauge Mediated SUSY Breaking in Diphoton Events in proton anti-proton Collisions at s**(1/2) = 1.96-TeV

    SciTech Connect (OSTI)

    Kim, Minsuk

    2004-12-01

    The authors present the results of a search for anomalous production of diphoton events with large missing transverse energy using the Collider Detector at Fermilab. In 202 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV they observe no candidate events, with an expected standard model background of 0.27 {+-} 0.07(stat) {+-} 0.10(syst) events. The results exclude a lightest chargino of mass less than 167 GeV/c{sup 2}, and lightest neutralino of 93 GeV/c{sup 2} at 95% confidence level in a gauge-mediated supersymmetry-breaking model with a light gravitino.

  1. Analysis of the PBF in-pile large-break LOCA test results with FRAP-T6/BALON-2. [PWR

    SciTech Connect (OSTI)

    Broughton, J.M.; Golden, D.W.; Hagrman, D.L.

    1982-01-01

    A series of four, large-break loss-of-coolant accident fuel behavior experiments have been performed in the Power Burst Facility (PBF) at the Idaho Engineering Laboratory. These experiments have been analyzed by using out-of-pile data to understand the phenomenology of zircaloy cladding ballooning and to construct a mechanistic computer code to describe cladding deformation and failure. The code was then used to quantify the influence of rod internal pressure, cladding heatup, and cladding circumferential temperature differences on ballooning and rupture for fresh and irradiated test rods in the PBF. The analysis indicates that the timing and magnitude of cladding circumferential temperature differences are the primary controlling parameters. Both the experimental and the analytical results support the hypothesis that previously irradiated rods exhibit greater cladding strain at failure than do fresh rods because of small local temperature differences within the cladding.

  2. TRAC-PF1/MOD1 analysis of a 200% cold-leg break in a US/Japanese PWR with four loops and 15 x 15 fuel

    SciTech Connect (OSTI)

    Spore, J.W.; Cappiello, M.W.

    1986-01-01

    This report presents the results of a TRAC-PF1/MOD1 calculation that simulated a 200% double-ended cold-leg-break loss-of-coolant accident in a generic US/Japanese pressurized water reactor. This is a best-estimate analysis using conservative boundary conditions and minimum safeguards. The calculation shows that the peak cladding temperature (PCT) occurs during blowdown and that the core reheat is minimal during reflood. The results also show that for an evaluation-model peak rod linear power of 15.85 kW/ft, a PCT of 1084 K is reached at 3.5 s into the blowdown transient, which is approx.394 K below the design basis limit of 1478 K. 10 figs.

  3. Symmetry breaking and electrical frustration during tip-induced polarization switching in the non-polar cut of lithium niobate single crystals

    SciTech Connect (OSTI)

    Ievlev, Anton; Alikin, Denis O; Morozovska, A. N.; Varenyk, O. V.; Eliseev, E. A.; Kholkin, Andrei; Shur, Vladimir Ya.; Kalinin, Sergei V

    2015-01-01

    Polarization switching in ferroelectric materials is governed by a delicate interplay between bulk polarization dynamics and screening processes at surfaces and domain walls. Here we explore the mechanism of tip-induced polarization switching in the non-polar cuts of uniaxial ferroelectrics. In this case, in-plane component of polarization vector switches, allowing for detailed observations of resultant domain morphologies. We observe surprising variability of resultant domain morphologies stemming from fundamental instability of formed charged domain wall and associated electric frustration. In particular, we demonstrate that controlling vertical tip position allows the polarity of the switching to be controlled. This represents very unusual form of symmetry breaking where mechanical motion in vertical direction controls the lateral domain growth. The implication of these studies for ferroelectric devices and domain wall electronics are discussed.

  4. Study to develop an inspection, maintenance, and repair plan for OTEC (Ocean Thermal Energy Conversion) modular experiment plants. Final report

    SciTech Connect (OSTI)

    Not Available

    1980-04-01

    The inspection, maintenance and repair (IM and R) of the Ocean Thermal Energy Conversion (OTEC) Modular Experiment Plant (Pilot Plant) have been studied in two phases: Task I and Task II. Task I phase developed IM and R identification forms, identified requirements for routine and post casualty IM and R, and categorized and outlined potential procedures to perform IM and R activities. The efforts of the Task II phase have been directed to meet the following objectives: to provide feedback to the OTEC marine systems designs to assure that such designs reflect appropriate consideration of IM and R methods and unit costs, resulting in designs with reduced life cycle costs; to include technical information concerning OTEC IM and R possibilities to NOAA/DOE; to outline a basis in which the anticipated IM and R contributions to life cycle costs can be developed for any specific OTEC plant design; to identify IM and R methods within the state-of-the-art in the offshore industry; to determine the application of potential IM and R procedures for the commercial operation of OTEC 10/40 Pilot Plant(s); and input into the US government formulation of statutory and regulatory IM and R requirements for OTEC plants.

  5. Benchmarking for electric utilities, tree trimming benchmarking, service line installation to single family residence, and distribution revenue meter testing and repair

    SciTech Connect (OSTI)

    Harder, J.

    1994-12-31

    An American Public Power Association (APPA) task force study on benchmarking for electric utilities is presented. Benchmark studies were made of three activities: (1) Tree trimming; (2) Service line installation to single family residence; (3) Distribution revenue meter testing and repair criteria. The results of the study areas are summarized for 15 utilities. The methodologies used for data collection and analysis are discussed. 28 figs., 9 tabs.

  6. Decreased cell survival and DNA repair capacity after UVC irradiation in association with down-regulation of GRP78/BiP in human RSa cells

    SciTech Connect (OSTI)

    Zhai Ling; Kita, Kazuko . E-mail: kita@faculty.chiba-u.jp; Wano, Chieko; Wu Yuping; Sugaya, Shigeru; Suzuki, Nobuo

    2005-05-01

    In contrast to extensive studies on the roles of molecular chaperones, such as heat shock proteins, there are only a few reports about the roles of GRP78/BiP, an endoplasmic reticulum (ER) stress-induced molecular chaperone, in mammalian cell responses to DNA-damaging stresses. To investigate whether GRP78/BiP is involved in resistance to a DNA-damaging agent, UVC (principally 254 nm in wavelength), we established human cells with down-regulation of GRP78/BiP by transfection of human RSa cells with antisense cDNA for GRP78/BiP. We found that the transfected cells showed higher sensitivity to UVC-induced cell death than control cells transfected with the vector alone. In the antisense-cDNA transfected cells, the removal capacities of the two major types of UVC-damaged DNA (thymine dimers and (6-4) photoproducts) in vivo and DNA synthesis activity of whole cell extracts to repair UVC-irradiated plasmids in vitro were remarkably decreased compared with those in the control cells. Furthermore, the antisense-cDNA transfected cells also showed slightly higher sensitivity to cisplatin-induced cell death than the control cells. Cisplatin-induced DNA damage is primarily repaired by nucleotide excision repair, like UVC-induced DNA damage. The present results suggest that GRP78/BiP plays a protective role against UVC-induced cell death possibly via nucleotide excision repair, at least in the human RSa cells tested.

  7. Better Buildings Residential Network Peer Exchange Call Series: Leveraging Service Calls and Emergency Repairs Call Slides and Discussion Summary, November 13, 2014

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

    Leveraging Service Calls and Emergency Repairs November 13, 2014 Call Slides and Discussion Summary Agenda  Call Logistics and Introductions  Go-around - please be prepared to state your name, organization, and interest in the topic  Residential Network and Peer Exchange Call Overview  Featured Speaker  Robert McCracken, Project Development Manager, Greater Cincinnati Energy Alliance - Residential Network Member  Discussion  What experience does your organization have with

  8. Construction of nerve guide conduits from cellulose/soy protein composite membranes combined with Schwann cells and pyrroloquinoline quinone for the repair of peripheral nerve defect

    SciTech Connect (OSTI)

    Luo, Lihua; Gan, Li; Liu, Yongming; Tian, Weiqun; Tong, Zan; Wang, Xiong; Huselstein, Celine; Chen, Yun

    2015-02-20

    Regeneration and functional reconstruction of peripheral nerve defects remained a significant clinical challenge. Nerve guide conduits, with seed cells or neurotrophic factors (NTFs), had been widely used to improve the repair and regeneration of injured peripheral nerve. Pyrroloquinoline quinone (PQQ) was an antioxidant that can stimulate nerve growth factors (NGFs) synthesis and accelerate the Schwann cells (SCs) proliferation and growth. In present study, three kinds of nerve guide conduits were constructed: one from cellulose/SPI hollow tube (CSC), another from CSC combined with SCs (CSSC), and the third one from CSSC combined with PQQ (CSSPC), respectively. And then they were applied to bridge and repair the sciatic nerve defect in rats, using autograft as control. Effects of different nerve guide conduits on the nerve regeneration were comparatively evaluated by general analysis, sciatic function index (SFI) and histological analysis (HE and TEM). Newly-formed regenerative nerve fibers were observed and running through the transparent nerve guide conduits 12 weeks after surgery. SFI results indicated that the reconstruction of motor function in CSSPC group was better than that in CSSC and CSC groups. HE images from the cross-sections and longitudinal-sections of the harvested regenerative nerve indicated that regenerative nerve fibers had been formed and accompanied with new blood vessels and matrix materials in the conduits. TEM images also showed that lots of fresh myelinated and non-myelinated nerve fibers had been formed. Parts of vacuolar, swollen and abnormal axons occurred in CSC and CSSC groups, while the vacuolization and swell of axons was the least serious in CSSPC group. These results indicated that CSSPC group had the most ability to repair and reconstruct the nerve structure and functions due to the comprehensive contributions from hollow CSC tube, SCs and PQQ. As a result, the CSSPC may have the potential for the applications as nerve guide

  9. Radiological consequences of ship collisions that might occur in U.S. Ports during the shipment of foreign research reactor spent nuclear fuel to the United States in break-bulk freighters

    SciTech Connect (OSTI)

    Sprung, J.L.; Bespalko, S.J.; Massey, C.D.; Yoshimura, R.; Johnson, J.D.; Reardon, P.C.; Ebert, M.W.; Gallagher D.W.

    1996-08-01

    Accident source terms, source term probabilities, consequences, and risks are developed for ship collisions that might occur in U.S. ports during the shipment of spent fuel from foreign research reactors to the United States in break-bulk freighters.

  10. Maximum Diameter Measurements of Aortic Aneurysms on Axial CT Images After Endovascular Aneurysm Repair: Sufficient for Follow-up?

    SciTech Connect (OSTI)

    Baumueller, Stephan Nguyen, Thi Dan Linh Goetti, Robert Paul; Lachat, Mario; Seifert, Burkhardt; Pfammatter, Thomas Frauenfelder, Thomas

    2011-12-15

    Purpose: To assess the accuracy of maximum diameter measurements of aortic aneurysms after endovascular aneurysm repair (EVAR) on axial computed tomographic (CT) images in comparison to maximum diameter measurements perpendicular to the intravascular centerline for follow-up by using three-dimensional (3D) volume measurements as the reference standard. Materials and Methods: Forty-nine consecutive patients (73 {+-} 7.5 years, range 51-88 years), who underwent EVAR of an infrarenal aortic aneurysm were retrospectively included. Two blinded readers twice independently measured the maximum aneurysm diameter on axial CT images performed at discharge, and at 1 and 2 years after intervention. The maximum diameter perpendicular to the centerline was automatically measured. Volumes of the aortic aneurysms were calculated by dedicated semiautomated 3D segmentation software (3surgery, 3mensio, the Netherlands). Changes in diameter of 0.5 cm and in volume of 10% were considered clinically significant. Intra- and interobserver agreements were calculated by intraclass correlations (ICC) in a random effects analysis of variance. The two unidimensional measurement methods were correlated to the reference standard. Results: Intra- and interobserver agreements for maximum aneurysm diameter measurements were excellent (ICC = 0.98 and ICC = 0.96, respectively). There was an excellent correlation between maximum aneurysm diameters measured on axial CT images and 3D volume measurements (r = 0.93, P < 0.001) as well as between maximum diameter measurements perpendicular to the centerline and 3D volume measurements (r = 0.93, P < 0.001). Conclusion: Measurements of maximum aneurysm diameters on axial CT images are an accurate, reliable, and robust method for follow-up after EVAR and can be used in daily routine.

  11. The DNA repair endonuclease XPG interacts directly and functionally with the WRN helicase defective in Werner syndrome

    SciTech Connect (OSTI)

    Trego, Kelly S.; Chernikova, Sophia B.; Davalos, Albert R.; Perry, J. Jefferson P.; Finger, L. David; Ng, Cliff; Tsai, Miaw-Sheue; Yannone, Steven M.; Tainer, John A.; Campisi, Judith; Cooper, Priscilla K.

    2011-04-20

    XPG is a structure-specific endonuclease required for nucleotide excision repair (NER). XPG incision defects result in the cancer-prone syndrome xeroderma pigmentosum, whereas truncating mutations of XPG cause the severe postnatal progeroid developmental disorder Cockayne syndrome. We show that XPG interacts directly with WRN protein, which is defective in the premature aging disorder Werner syndrome, and that the two proteins undergo similar sub-nuclear redistribution in S-phase and co-localize in nuclear foci. The co-localization was observed in mid- to late-S-phase, when WRN moves from nucleoli to nuclear foci that have been shown to contain protein markers of both stalled replication forks and telomeric proteins. We mapped the interaction between XPG and WRN to the C-terminal domains of each and show that interaction with the C-terminal domain of XPG strongly stimulates WRN helicase activity. WRN also possesses a competing DNA single-strand annealing activity that, combined with unwinding, has been shown to coordinate regression of model replication forks to form Holliday junction/chicken foot intermediate structures. We tested whether XPG stimulated WRN annealing activity and found that XPG itself has intrinsic strand annealing activity that requires the unstructured R- and C-terminal domains, but not the conserved catalytic core or endonuclease activity. Annealing by XPG is cooperative, rather than additive, with WRN annealing. Taken together, our results suggest a novel function for XPG in S-phase that is at least in part carried out coordinately with WRN, and which may contribute to the severity of the phenotypes that occur upon loss of XPG.

  12. Endovascular Aortic Aneurysm Repair with the Talent Stent-Graft: Outcomes in Patients with Large Iliac Arteries

    SciTech Connect (OSTI)

    England, Andrew; Butterfield, John S.; McCollum, Charles N.; Ashleigh, Raymond J.

    2008-07-15

    The purpose of this study is to report outcomes following endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) in patients with ectatic common iliac arteries (CIAs). Of 117 AAA patients treated by EVAR between 1998 and 2005, 87 (74%) had CIAs diameters <18 mm and 30 (26%) patients had one or more CIA diameters >18 but <25 mm. All patients were treated with Talent stent-grafts, 114 bifurcated and 3 AUI devices. Departmental databases and patient records were reviewed to assess outcomes. Technical success, iliac-related outcome, and iliac-related reintervention (IRSI) were analyzed. Patients with EVAR extending into the external iliac artery were excluded. Median (range) follow-up for the study group was 24 (1-84) months. Initial technical success was 98% for CIAs <18 mm and 100% for CIAs {>=}18 mm (p = 0.551). There were three distal type I endoleaks (two in the ectatic group) and six iliac limb occlusions (one in an ectatic patient); there were no statistically significant differences between groups (p = 0.4). There were nine IRSIs (three stent-graft extensions, six femorofemoral crossover grafts); three of these patients had one or both CIAs {>=}18 mm (p = 0.232). One-year freedom from IRSI was 92% {+-} 3% and 84% {+-} 9% for the <18-mm and {>=}18-mm CIA groups, respectively (p = 0.232). We conclude that the treatment of AAA by EVAR in patients with CIAs 18-24 mm appears to be safe and effective, however, it may be associated with more frequent reinterventions.

  13. STELLAR POPULATIONS OF LYMAN BREAK GALAXIES AT z {approx_equal} 1-3 IN THE HST/WFC3 EARLY RELEASE SCIENCE OBSERVATIONS

    SciTech Connect (OSTI)

    Hathi, N. P.; McCarthy, P. J.; Cohen, S. H.; Windhorst, R. A.; Rutkowski, M. J.; Ryan, R. E. Jr.; Koekemoer, A. M.; Bond, H. E.; Finkelstein, S. L.; Yan, H.; O'Connell, R. W.; Straughn, A. N.; Kimble, R. A.; Balick, B.; Calzetti, D.; Disney, M. J.; Dopita, M. A.; Frogel, Jay A.; Hall, D. N. B.; Holtzman, J. A.; and others

    2013-03-10

    We analyze the spectral energy distributions (SEDs) of Lyman break galaxies (LBGs) at z {approx_equal} 1-3 selected using the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) UVIS channel filters. These HST/WFC3 observations cover about 50 arcmin{sup 2} in the GOODS-South field as a part of the WFC3 Early Release Science program. These LBGs at z {approx_equal} 1-3 are selected using dropout selection criteria similar to high-redshift LBGs. The deep multi-band photometry in this field is used to identify best-fit SED models, from which we infer the following results: (1) the photometric redshift estimate of these dropout-selected LBGs is accurate to within few percent; (2) the UV spectral slope {beta} is redder than at high redshift (z > 3), where LBGs are less dusty; (3) on average, LBGs at z {approx_equal} 1-3 are massive, dustier, and more highly star forming, compared to LBGs at higher redshifts with similar luminosities (0.1L* {approx}< L {approx}< 2.5L*), though their median values are similar within 1{sigma} uncertainties. This could imply that identical dropout selection technique, at all redshifts, finds physically similar galaxies; and (4) the stellar masses of these LBGs are directly proportional to their UV luminosities with a logarithmic slope of {approx}0.46, and star formation rates are proportional to their stellar masses with a logarithmic slope of {approx}0.90. These relations hold true-within luminosities probed in this study-for LBGs from z {approx_equal} 1.5 to 5. The star-forming galaxies selected using other color-based techniques show similar correlations at z {approx_equal} 2, but to avoid any selection biases, and for direct comparison with LBGs at z > 3, a true Lyman break selection at z {approx_equal} 2 is essential. The future HST UV surveys, both wider and deeper, covering a large luminosity range are important to better understand LBG properties and their evolution.

  14. Cellular response to low dose radiation: Role of phosphatidylinositol-3 kinase like kinases

    SciTech Connect (OSTI)

    Balajee, A.S.; Meador, J.A.; Su, Y.

    2011-03-24

    It is increasingly realized that human exposure either to an acute low dose or multiple chronic low doses of low LET radiation has the potential to cause different types of cancer. Therefore, the central theme of research for DOE and NASA is focused on understanding the molecular mechanisms and pathways responsible for the cellular response to low dose radiation which would not only improve the accuracy of estimating health risks but also help in the development of predictive assays for low dose radiation risks associated with tissue degeneration and cancer. The working hypothesis for this proposal is that the cellular mechanisms in terms of DNA damage signaling, repair and cell cycle checkpoint regulation are different for low and high doses of low LET radiation and that the mode of action of phosphatidylinositol-3 kinase like kinases (PIKK: ATM, ATR and DNA-PK) determines the dose dependent cellular responses. The hypothesis will be tested at two levels: (I) Evaluation of the role of ATM, ATR and DNA-PK in cellular response to low and high doses of low LET radiation in simple in vitro human cell systems and (II) Determination of radiation responses in complex cell microenvironments such as human EpiDerm tissue constructs. Cellular responses to low and high doses of low LET radiation will be assessed from the view points of DNA damage signaling, DNA double strand break repair and cell cycle checkpoint regulation by analyzing the activities (i.e. post-translational modifications and kinetics of protein-protein interactions) of the key target proteins for PI-3 kinase like kinases both at the intra-cellular and molecular levels. The proteins chosen for this proposal are placed under three categories: (I) sensors/initiators include ATM ser1981, ATR, 53BP1, gamma-H2AX, MDC1, MRE11, Rad50 and Nbs1; (II) signal transducers include Chk1, Chk2, FANCD2 and SMC1; and (III) effectors include p53, CDC25A and CDC25C. The primary goal of this proposal is to elucidate the

  15. A DEEP SEARCH FOR MOLECULAR GAS IN TWO MASSIVE LYMAN BREAK GALAXIES AT z = 3 AND 4: VANISHING CO-EMISSION DUE TO LOW METALLICITY?

    SciTech Connect (OSTI)

    Tan, Q.; Gao, Y.; Daddi, E.; Sargent, M.; Béthermin, M.; Bournaud, F.; Elbaz, D.; Pannella, M.; Hodge, J.; Walter, F.; Carilli, C.; Owen, F.; Dannerbauer, H.; Dickinson, M.; Morrison, G.; Riechers, D.

    2013-10-20

    We present deep IRAM Plateau de Bure Interferometer observations, searching for CO-emission toward two massive, non-lensed Lyman break galaxies at z = 3.216 and 4.058. With one low significance CO detection (3.5σ) and one sensitive upper limit, we find that the CO lines are ∼>3-4 times weaker than expected based on the relation between IR and CO luminosities followed by similarly massive galaxies at z = 0-2.5. This is consistent with a scenario in which these galaxies have low metallicity, causing an increased CO-to-H{sub 2} conversion factor, i.e., weaker CO-emission for a given molecular (H{sub 2}) mass. The required metallicities at z > 3 are lower than predicted by the fundamental metallicity relation at these redshifts, consistent with independent evidence. Unless our galaxies are atypical in this respect, detecting molecular gas in normal galaxies at z > 3 may thus remain challenging even with ALMA.

  16. Multiloop integral system test (MIST): Test Group 31, SBLOCA (small-break loss-of-coolant accident) with varied boundary conditions

    SciTech Connect (OSTI)

    Gloudemans, J.R. . Nuclear Power Div.)

    1989-07-01

    The multiloop integral system test (MIST) is part of a multiphase program started in 1983 to address small-break loss-of-coolant accidents (SBLOCAs) specific to Babcock and Wilcox-designed plants. MIST is sponsored by the US Nuclear Regulatory Commission, the Babcock and Wilcox Owners Group, the Electric Power Research Institute, and Babcock and Wilcox. The unique features of the Babcock and Wilcox design, specifically the hot leg U-bends and steam generators, prevented the use of existing integral system data or existing integral system facilities to address the thermal-hydraulic SBLOCA questions. MIST and two other supporting facilities were specifically designed and constructed for this program, and an existing facility --- the once-through integral system (OTIS) --- was also used. Data from MIST and the other facilities will be used to benchmark the adequacy of system codes, such as RELAP-5 and TRAC, for predicting abnormal plant transients. The MIST program is reported in 11 volumes. The program is summarized in Volume 1; Volumes 2 through 8 describe groups of tests by test type; Volume 9 presents inter-group comparisons; Volume 10 provides comparisons between the calculations of RELAP5 MOD2 and MIST observations, and Volume 11 presents the later, Phase 4 tests. This is Volume 3 pertaining to Test Group 31, Boundary Conditions Variations. The specifications, conduct, observations, and results of these tests are described. 8 refs., 328 figs., 15 tabs.

  17. Light hadron spectra in the constituent quark model with the Kobayashi-Kondo-Maskawa-'t Hooft effective U {sub A} (1) symmetry breaking interaction

    SciTech Connect (OSTI)

    Dmitrasinovic, V. . E-mail: dmitrasin@yahoo.com; Toki, H.

    2006-02-15

    We make a critical comparison of several versions of instanton-induced interactions present in the literature, all based on ITEP group's extension to three colours and flavours of 't Hooft's effective lagrangian, with the predictions of the phenomenological Kobayashi-Kondo-Maskawa (KKM) chiral quark lagrangian. We analyze the effects of all versions of the effective U {sub A} (1) symmetry breaking interactions on light hadron spectra in the non-relativistic constituent quark model. We show that the KKMT force, when used as a residual hyperfine interaction reproduces the correct ordering of pseudoscalar and vector mesons even without explicitly taking chiral symmetry into account. Moreover, the nucleon spectra are also correctly reproduced, only the Roper resonance remains too high, albeit lower than usual, at 1660 MeV. The latter's lower than expected mass is not due to a small excitation energy, as in the Glozman-Riska (GR) model, but to a combination of colour, flavour, and spatial wave function properties that enhance the relevant matrix elements. The KKMT interaction explicitly depends on flavour and spin of the quarks, but unlike the GR flavour-spin one it has a firm footing in QCD. In the process we provide several technical advances, in particular we show the first explicit derivation of the three-body Fierz transformation and apply it to the KKM interaction. We also discuss the ambiguities associated with the colour degree of freedom.

  18. The breaks and the hidden components in the power-law spectra of synchrotron radiation of the self-consistent current structures

    SciTech Connect (OSTI)

    Kocharovsky, V. V.; Kocharovsky, VI. V.; Tarasov, S. V.; Martyanov, V. Ju.

    2015-08-15

    Widespread use of a broken-power-law description of the spectra of synchrotron emission of various plasma objects requires an analysis of origin and a proper interpretation of spectral components. We show that, for a self-consistent magnetic configuration in a collisionless plasma, these components may be angle-dependent according to an anisotropic particle momentum distribution and may have no counterparts in a particle energy distribution. That has never been studied analytically and is in contrast to a usual model of synchrotron radiation, assuming an external magnetic field and a particle ensemble with isotropic momentum distribution. We demonstrate that for the wide intervals of observation angle the power-law spectra and, in particular, the positions and number of spectral breaks may be essentially different for the cases of the self-consistent and not-self-consistent magnetic fields in current structures responsible for the synchrotron radiation of the ensembles of relativistic particles with the multi-power-law energy distributions.

  19. Application of analytical capability to predict rapid cladding cooling and quench during the blowdown phase of a large break loss-of-coolant accident. [PWR

    SciTech Connect (OSTI)

    Aksan, S.N.; Tolman, E.L.; Nelson, R.A.

    1983-01-01

    Large-break Experiments L2-2 and L2-3 conducted in the Loss-of-Fluid Test (LOFT) facility experienced core-wide rapid quenches early in the blowdown transients. To further investigate rapid cladding quenches, separate effects experiments using Semiscale solid-type electric heater rods were conducted in the LOFT Test Support Facility (LTSF) over a wide range of inlet coolant conditions. The analytical capability to predict the cladding temperature response from selected LTSF experiments estimated to bound the hydraulic conditions causing the LOFT early blowdown quenches was investigated using the RELAP4 computer code and was shown to be acceptable over the film boiling cooldown phase. This analytical capability was then used to investigate the behavior of nuclear fuel rods under the same hydraulic conditions. The calculations show that, under rapid cooling conditions, the behaviors of nuclear and electrical heater rods are significantly different because the nuclear rods are conduction limited, while the electrical rods are convection limited.

  20. Conserved structural chemistry for incision activity in structurally non-homologous apurinic/apyrimidinic endonuclease APE1 and endonuclease IV DNA repair enzymes.

    SciTech Connect (OSTI)

    Tsutakawa, Susan E.; Shin, David S.; Mol, Clifford D.; Izum, Tadahide; Arvai, Andrew S.; Mantha, Anil K.; Szczesny, Bartosz; Ivanov, Ivaylo N.; Hosfield, David J.; Maiti, Buddhadev; Pique, Mike E.; Frankel, Kenneth A.; Hitomi, Kenichi; Cunningham, Richard P.; Mitra, Sankar; Tainer, John A.

    2013-03-22

    Non-coding apurinic/apyrimidinic (AP) sites in DNA form spontaneously and as DNA base excision repair intermediates are the most common toxic and mutagenic in vivo DNA lesion. For repair, AP sites must be processed by 5' AP endonucleases in initial stages of base repair. Human APE1 and bacterial Nfo represent the two conserved 5' AP endonuclease families in the biosphere; they both recognize AP sites and incise the phosphodiester backbone 5' to the lesion, yet they lack similar structures and metal ion requirements. Here, we determined and analyzed crystal structures of a 2.4 ? resolution APE1-DNA product complex with Mg(2+) and a 0.92 Nfo with three metal ions. Structural and biochemical comparisons of these two evolutionarily distinct enzymes characterize key APE1 catalytic residues that are potentially functionally similar to Nfo active site components, as further tested and supported by computational analyses. We observe a magnesium-water cluster in the APE1 active site, with only Glu-96 forming the direct protein coordination to the Mg(2+). Despite differences in structure and metal requirements of APE1 and Nfo, comparison of their active site structures surprisingly reveals strong geometric conservation of the catalytic reaction, with APE1 catalytic side chains positioned analogously to Nfo metal positions, suggesting surprising functional equivalence between Nfo metal ions and APE1 residues. The finding that APE1 residues are positioned to substitute for Nfo metal ions is supported by the impact of mutations on activity. Collectively, the results illuminate the activities of residues, metal ions, and active site features for abasic site endonucleases.

  1. Motor Repair Tech Brief

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

    ... This will assist in optimizing lubrication for your own ... Today's motors are more efficient. The National Electric ... and devices for assessing motor efficiency in the field. ...

  2. Remote repair appliance

    DOE Patents [OSTI]

    Heumann, Frederick K.; Wilkinson, Jay C.; Wooding, David R.

    1997-01-01

    A remote appliance for supporting a tool for performing work at a worksite on a substantially circular bore of a workpiece and for providing video signals of the worksite to a remote monitor comprising: a baseplate having an inner face and an outer face; a plurality of rollers, wherein each roller is rotatably and adjustably attached to the inner face of the baseplate and positioned to roll against the bore of the workpiece when the baseplate is positioned against the mouth of the bore such that the appliance may be rotated about the bore in a plane substantially parallel to the baseplate; a tool holding means for supporting the tool, the tool holding means being adjustably attached to the outer face of the baseplate such that the working end of the tool is positioned on the inner face side of the baseplate; a camera for providing video signals of the worksite to the remote monitor; and a camera holding means for supporting the camera on the inner face side of the baseplate, the camera holding means being adjustably attached to the outer face of the baseplate. In a preferred embodiment, roller guards are provided to protect the rollers from debris and a bore guard is provided to protect the bore from wear by the rollers and damage from debris.

  3. Remote repair appliance

    DOE Patents [OSTI]

    Heumann, F.K.; Wilkinson, J.C.; Wooding, D.R.

    1997-12-16

    A remote appliance for supporting a tool for performing work at a work site on a substantially circular bore of a work piece and for providing video signals of the work site to a remote monitor comprises: a base plate having an inner face and an outer face; a plurality of rollers, wherein each roller is rotatably and adjustably attached to the inner face of the base plate and positioned to roll against the bore of the work piece when the base plate is positioned against the mouth of the bore such that the appliance may be rotated about the bore in a plane substantially parallel to the base plate; a tool holding means for supporting the tool, the tool holding means being adjustably attached to the outer face of the base plate such that the working end of the tool is positioned on the inner face side of the base plate; a camera for providing video signals of the work site to the remote monitor; and a camera holding means for supporting the camera on the inner face side of the base plate, the camera holding means being adjustably attached to the outer face of the base plate. In a preferred embodiment, roller guards are provided to protect the rollers from debris and a bore guard is provided to protect the bore from wear by the rollers and damage from debris. 5 figs.

  4. Investigations of DNA damage induction and repair resulting from cellular exposure to high dose-rate pulsed proton beams

    SciTech Connect (OSTI)

    Renis, M.; Malfa, G.; Tomasello, B.; Borghesi, M.; Schettino, G.; Favetta, M.; Romano, F.; Cirrone, G. A. P.; Manti, L.

    2013-07-26

    following irradiation in a dose-dependent manner. The analysis of repair capability showed that the cells irradiated with 1 and 2 Gy almost completely recovered from the damage, but not, however, 3 Gy treated cells in which DNA damage was not recovered. In addition, the results indicate the importance of the use of an appropriate control in radiobiological in vitro analysis.

  5. DNB CP - Steamline Break Analysis

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

    * Fuel design improvement (STAR-CCM+ CFD) - Higher fidelity of multi-phase M&S ... geometry and grid spacer designs for CFD modeling 5 CASL-U-2016-1085-000 CASL Focus ...

  6. Foinaven development - breaking the mould

    SciTech Connect (OSTI)

    Maclean, C.H.J.; Boyd, J.D.; Smith, P.J.

    1996-12-31

    Foinaven Phase 1, the first oil field development West of Shetland (UK), has produced a new standard in the time between discovery and first oil. This performance improvement stems from the clarity of hydrocarbon imaging available with new technology based on 3D seismic data. Oil in the Foinaven field (discovered in late 1992) lies within Palaeocene reservoir sands. Reservoir quality is excellent, although the sands are relatively thin, distributed over a large area and are overlain by a gas cap. Prior to appraisal drilling, 3D seismic data were acquired as part of an extensive 2000 sq. km. survey shot in the summer of 1993. The conventional 3D seismic data were inverted to produce an acoustic impedance (Al) dataset. Comparisons of Al-predicted vs. actual hydrocarbon pore thickness during appraisal drilling have shown a typical variance of less than +/- 10%. A horizontal appraisal well was spudded in mid-1994. Once the target reservoir was entered, directional information from MWD was used to steer the well along a desired path in real time to intersect specific targets. The hole was completed using a pre-packed production liner. An extended well test using a semi-submersible linked to a shuttle tanker was undertaken, and over 400,000 bbi of oil were produced. This extended test yielded significant long-term development information. This combination of technologies - seismic, drilling and extended well test - has proved invaluable in advancing the appraisal of Foinaven. Foinaven Phase I is being developed by Petrojarl IV, a ship shaped FPSO facility. Horizontal production wells will be used with subsea completion, and following processing the crude oil will be exported by shuttle tanker. Development drilling started in November 1994. First oil is programmed for early 1996 at a plateau rate around 85 mbd.

  7. Foinaven development - breaking the mould

    SciTech Connect (OSTI)

    Maclean, C.H.J.; Boyd, J.D.; Smith, P.J. )

    1996-01-01

    Foinaven Phase 1, the first oil field development West of Shetland (UK), has produced a new standard in the time between discovery and first oil. This performance improvement stems from the clarity of hydrocarbon imaging available with new technology based on 3D seismic data. Oil in the Foinaven field (discovered in late 1992) lies within Palaeocene reservoir sands. Reservoir quality is excellent, although the sands are relatively thin, distributed over a large area and are overlain by a gas cap. Prior to appraisal drilling, 3D seismic data were acquired as part of an extensive 2000 sq. km. survey shot in the summer of 1993. The conventional 3D seismic data were inverted to produce an acoustic impedance (Al) dataset. Comparisons of Al-predicted vs. actual hydrocarbon pore thickness during appraisal drilling have shown a typical variance of less than +/- 10%. A horizontal appraisal well was spudded in mid-1994. Once the target reservoir was entered, directional information from MWD was used to steer the well along a desired path in real time to intersect specific targets. The hole was completed using a pre-packed production liner. An extended well test using a semi-submersible linked to a shuttle tanker was undertaken, and over 400,000 bbi of oil were produced. This extended test yielded significant long-term development information. This combination of technologies - seismic, drilling and extended well test - has proved invaluable in advancing the appraisal of Foinaven. Foinaven Phase I is being developed by Petrojarl IV, a ship shaped FPSO facility. Horizontal production wells will be used with subsea completion, and following processing the crude oil will be exported by shuttle tanker. Development drilling started in November 1994. First oil is programmed for early 1996 at a plateau rate around 85 mbd.

  8. Supersymmetry Breaking Casimir Warp Drive

    SciTech Connect (OSTI)

    Obousy, Richard K.; Cleaver, Gerald

    2007-01-30

    This paper utilizes a recent model which relates the cosmological constant to the Casimir energy of the extra dimensions in brane-world theories. The objective of this paper is to demonstrate that, given some sufficiently advanced civilization with the ability to manipulate the radius of the extra dimension, a local adjustment of the cosmological constant could be created. This adjustment would facilitate an expansion/contraction of the spacetime around a spacecraft creating an exotic form of field-propulsion. This idea is analogous to the Alcubierre bubble, but differs entirely in the approach, utilizing the physics of higher dimensional quantum field theory, instead of general relativity.

  9. System Break-Out Session

    Office of Environmental Management (EM)

    Better batteries and electric drivetrains Lightweight materials, stronger than steel Better biofuels and other petroleum replacements More effi cient internal combustion engines n Home-grown fuels: Lowered the cost of non- food-based ethanol by more than $6/gallon since 2001-now projected to be cost-competitive with gasoline priced at $3.20/gallon when ramped up to a commercial scale[4]. n Fuel cells: Reduced the cost of manufacturing automotive fuel cells by more than 30% since 2008 and 80%

  10. The Carina project. VII. Toward the breaking of the age-metallicity degeneracy of red giant branch stars using the C {sub U,} {sub B,} {sub I} index

    SciTech Connect (OSTI)

    Monelli, M.; Milone, A. P.; Gallart, C.; Aparicio, A. [Instituto de Astrofsica de Canarias, Calle Via Lactea s/n, E-38205 La Laguna, Tenerife (Spain); Fabrizio, M.; Cassisi, S.; Buonanno, R. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico Collurania, Via M. Maggini, I-64100 Teramo (Italy); Bono, G. [Dipartimento di Fisica, Universit di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Rome (Italy); Stetson, P. B. [Dominion Astrophysical Observatory, NRC-Herzberg, 5071 West Saanich Road, Victoria, BC, V9E 2E7 (Canada); Walker, A. R. [Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, Casilla 603, La Serena (Chile); Nonino, M. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Trieste, Via G. B. Tiepolo 11, I-40131 Trieste (Italy); Dall'Ora, M. [INAFOsservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); Ferraro, I.; Iannicola, G.; Pulone, L. [Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Roma, Via Frascati 33, Monte Porzio Catone, I-00044 Rome (Italy); Thvenin, F., E-mail: monelli@iac.es [Universit de Nice Sophia-antipolis, CNRS, Observatoire de la Cte d'Azur, Laboratoire Lagrange, BP 4229, F-06304 Nice (France)

    2014-12-01

    We present an analysis of photometric and spectroscopic data of the Carina dSph galaxy, testing a new approach similar to that used to disentangle multiple populations in Galactic globular clusters (GCs). We show that a proper color combination is able to separate a significant fraction of the red giant branch (RGB) of the two main Carina populations (the old one, ?12 Gyr, and the intermediate-age one, 4-8 Gyr). In particular, the c {sub U,} {sub B,} {sub I} = (U B) (B I) pseudo-color allows us to follow the RGB of both populations along a relevant portion of the RGB. We find that the oldest stars have a more negative c {sub U,} {sub B,} {sub I} pseudo-color than intermediate-age ones. We correlate the pseudo-color of RGB stars with their chemical properties, finding a significant trend between the iron content and the c {sub U,} {sub B,} {sub I}. Stars belonging to the old population are systematically more metal-poor ([Fe/H] =2.32 0.08 dex) than the intermediate-age ones ([Fe/H] =1.82 0.03 dex). This gives solid evidence of the chemical evolution history of this galaxy, and we have a new diagnostic that can allow us to break the age-metallicity degeneracy of H-burning advanced evolutionary phases. We compared the distribution of stars in the c {sub U,} {sub B,} {sub I} plane with theoretical isochrones, finding that no satisfactory agreement can be reached with models developed in a theoretical framework based on standard heavy element distributions. Finally, we discuss possible systematic differences when compared with multiple populations in GCs.

  11. HerMES: LYMAN BREAK GALAXIES INDIVIDUALLY DETECTED AT 0.7 {<=} z {<=} 2.0 IN GOODS-N WITH HERSCHEL/SPIRE

    SciTech Connect (OSTI)

    Burgarella, D.; Heinis, S.; Buat, V.; Giovannoli, E.; Ilbert, O.; Magdis, G.; Hwang, H. S.; Blain, A.; Bock, J.; Cooray, A.; Brisbin, D.; Chanial, P.; Clements, D. L.; Franceschini, A.; Marchetti, L.; Glenn, J.; Gonzalez Solares, E. A. E-mail: sebastien.heinis@oamp.fr

    2011-06-10

    As part of the Herschel Multi-tiered Extragalactic Survey we have investigated the rest-frame far-infrared (FIR) properties of a sample of more than 4800 Lyman break galaxies (LBGs) in the Great Observatories Origins Deep Survey North field. Most LBGs are not detected individually, but we do detect a sub-sample of 12 objects at 0.7 < z < 1.6 and one object at z = 2.0. The ones detected by Herschel SPIRE have redder observed NUV - U and U - R colors than the others, while the undetected ones have colors consistent with average LBGs at z > 2.5. The UV-to-FIR spectral energy distributions of the objects detected in the rest-frame FIR are investigated using the code CIGALE to estimate physical parameters. We find that LBGs detected by SPIRE are high-mass, luminous infrared galaxies. It appears that LBGs are located in a triangle-shaped region in the A{sub FUV} versus log L{sub FUV} = 0 diagram limited by A{sub FUV} = 0 at the bottom and by a diagonal following the temporal evolution of the most massive galaxies from the bottom right to the top left of the diagram. This upper envelop can be used as upper limits for the UV dust attenuation as a function of L{sub FUV}. The limits of this region are well explained using a closed-box model, where the chemical evolution of galaxies produces metals, which in turn lead to higher dust attenuation when the galaxies age.

  12. Site directed recombination

    DOE Patents [OSTI]

    Jurka, Jerzy W.

    1997-01-01

    Enhanced homologous recombination is obtained by employing a consensus sequence which has been found to be associated with integration of repeat sequences, such as Alu and ID. The consensus sequence or sequence having a single transition mutation determines one site of a double break which allows for high efficiency of integration at the site. By introducing single or double stranded DNA having the consensus sequence flanking region joined to a sequence of interest, one can reproducibly direct integration of the sequence of interest at one or a limited number of sites. In this way, specific sites can be identified and homologous recombination achieved at the site by employing a second flanking sequence associated with a sequence proximal to the 3'-nick.

  13. Three-dimensional Invasion of Human Glioblastoma Cells Remains Unchanged by X-ray and Carbon Ion Irradiation In Vitro

    SciTech Connect (OSTI)

    Eke, Iris; Storch, Katja; Kaestner, Ina; Vehlow, Anne; Faethe, Christina; Mueller-Klieser, Wolfgang; Taucher-Scholz, Gisela; Temme, Achim; Schackert, Gabriele; Department of Radiation Oncology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Dresden

    2012-11-15

    Purpose: Cell invasion represents one of the major determinants that treatment has failed for patients suffering from glioblastoma. Contrary findings have been reported for cell migration upon exposure to ionizing radiation. Here, the migration and invasion capability of glioblastoma cells on and in collagen type I were evaluated upon irradiation with X-rays or carbon ions. Methods and Materials: Migration on and invasion in collagen type I were evaluated in four established human glioblastoma cell lines exposed to either X-rays or carbon ions. Furthermore, clonogenic radiation survival, proliferation (5-bromo-2-deoxyuridine positivity), DNA double-strand breaks ({gamma}H2AX/53BP1-positive foci), and expression of invasion-relevant proteins (eg, {beta}1 integrin, FAK, MMP2, and MMP9) were explored. Migration and invasion assays for primary glioblastoma cells also were carried out with X-ray irradiation. Results: Neither X-ray nor carbon ion irradiation affected glioblastoma cell migration and invasion, a finding similarly observed in primary glioblastoma cells. Intriguingly, irradiated cells migrated unhampered, despite DNA double-strand breaks and reduced proliferation. Clonogenic radiation survival was increased when cells had contact with extracellular matrix. Specific inhibition of the {beta}1 integrin or proliferation-associated signaling molecules revealed a critical function of JNK, PI3K, and p38 MAPK in glioblastoma cell invasion. Conclusions: These findings indicate that X-rays and carbon ion irradiation effectively reduce proliferation and clonogenic survival without modifying the migration and invasion ability of glioblastoma cells in a collagen type I environment. Addition of targeted agents against members of the MAPK and PI3K signaling axis to conventional chemoradiation therapy seems potentially useful to optimize glioblastoma therapy.

  14. Using the OECD/NRC Pressurized Water Reactor Main Steam Line Break Benchmark to Study Current Numerical and Computational Issues of Coupled Calculations

    SciTech Connect (OSTI)

    Ivanov, Kostadin N.; Todorova, Nadejda K.; Sartori, Enrico

    2003-05-15

    Incorporating full three-dimensional (3-D) models of the reactor core into system transient codes allows for a 'best-estimate' calculation of interactions between the core behavior and plant dynamics. Recent progress in computer technology has made the development of coupled thermal-hydraulic (T-H) and neutron kinetics code systems feasible. Considerable efforts have been made in various countries and organizations in this direction. Appropriate benchmarks need to be developed that will permit testing of two particular aspects. One is to verify the capability of the coupled codes to analyze complex transients with coupled core-plant interactions. The second is to test fully the neutronics/T-H coupling. One such benchmark is the Pressurized Water Reactor Main Steam Line Break (MSLB) Benchmark problem. It was sponsored by the Organization for Economic Cooperation and Development, U.S. Nuclear Regulatory Commission, and The Pennsylvania State University. The benchmark problem uses a 3-D neutronics core model that is based on real plant design and operational data for the Three Mile Island Unit 1 nuclear power plant. The purpose of this benchmark is threefold: to verify the capability of system codes for analyzing complex transients with coupled core-plant interactions; to test fully the 3-D neutronics/T-H coupling; and to evaluate discrepancies among the predictions of coupled codes in best-estimate transient simulations. The purposes of the benchmark are met through the application of three exercises: a point kinetics plant simulation (exercise 1), a coupled 3-D neutronics/core T-H evaluation of core response (exercise 2), and a best-estimate coupled core-plant transient model (exercise 3).In this paper we present the three exercises of the MSLB benchmark, and we summarize the findings of the participants with regard to the current numerical and computational issues of coupled calculations. In addition, this paper reviews in some detail the sensitivity studies on

  15. STELLAR POPULATIONS OF Ly{alpha} EMITTERS AT z = 4.86: A COMPARISON TO z {approx} 5 LYMAN BREAK GALAXIES

    SciTech Connect (OSTI)

    Yuma, Suraphong; Ohta, Kouji; Yabe, Kiyoto; Shimasaku, Kazuhiro; Yoshida, Makiko; Ouchi, Masami; Iwata, Ikuru; Sawicki, Marcin

    2010-09-10

    We present a study of a stellar population of Ly{alpha} emitters (LAEs) at z = 4.86 in the Great Observatories Origins Deep Survey North (GOODS-N) field and its flanking field. The LAEs are selected based on optical narrowband (NB711) and broadband (V, I{sub c} , and z') observations by the Suprime-Cam attached to the Subaru Telescope. With the publicly available Infrared Array Camera (IRAC) data in GOODS-N and further IRAC observations in the flanking fields, we select five LAEs that are not contaminated by neighboring objects in IRAC images and construct their observed spectral energy distributions (SEDs) with I{sub c} , z', IRAC 3.6 {mu}m, and 4.5 {mu}m band photometries. The SEDs cover the rest-frame UV-to-optical wavelengths. We derive the stellar masses, ages, color excesses, and star formation rates (SFRs) of the five LAEs using an SED fitting method. Assuming a constant star formation history, we find that the stellar masses range from 10{sup 8} to 10{sup 10} M {sub sun} with the median value of 2.5 x 10{sup 9} M{sub sun}. The derived ages range from very young (7.4 Myr) to 437 Myr, with a median age of 25 Myr. The color excess E(B - V) is between 0.1and0.4 mag. SFRs are 55-209 M{sub sun} yr{sup -1}. A comparison of the stellar populations is made between 3 LAEs and 88 Lyman break galaxies (LBGs) selected at the same redshift, in the same observed field, and down to the same limit of the rest-frame UV luminosity. These three LAEs are the brightest and reddest samples of all the LAE samples at z = 4.86. The LAEs are distributed at the relatively faint part of the UV-luminosity distribution of LBGs. Deriving the stellar properties of the LBGs by fitting their SEDs with the same model ensures that model difference does not affect the comparison. It is found that the stellar properties of the LAEs are located in the region where the properties of LBGs are distributed. On average, the LAEs show less dust extinction and lower SFRs than LBGs, while the stellar

  16. THE GREAT OBSERVATORIES ORIGINS DEEP SURVEY: CONSTRAINTS ON THE LYMAN CONTINUUM ESCAPE FRACTION DISTRIBUTION OF LYMAN-BREAK GALAXIES AT 3.4 < z < 4.5

    SciTech Connect (OSTI)

    Vanzella, E.; Nonino, M.; Fontanot, F.; Cristiani, S.; Tozzi, P.; Giavalisco, M.; Inoue, A. K.; Grazian, A.; Giallongo, E.; Boutsia, K.; Fontana, A.; Pentericci, L.; Dickinson, M.; Stern, D.; Ferguson, H.; Spinrad, H.; Rosati, P.

    2010-12-10

    We use ultra-deep ultraviolet VLT/VIMOS intermediate-band and VLT/FORS1 narrowband imaging in the GOODS Southern field to derive limits on the distribution of the escape fraction (f{sub esc}) of ionizing radiation for L {>=} L*{sub z=3} Lyman-break galaxies (LBGs) at redshift 3.4-4.5. Only one LBG, at redshift z = 3.795, is detected in its Lyman continuum (LyC; S/N {approx_equal} 5.5), the highest redshift galaxy currently known with a direct detection. Its ultraviolet morphology is quite compact (R{sub eff} = 0.8 kpc physical). Three out of seven active galactic nuclei are also detected in their LyC, including one at redshift z = 3.951 and z{sub 850} = 26.1. From stacked data (LBGs), we set an upper limit to the average f{sub esc} in the range 5%-20%, depending on how the data are selected (e.g., by magnitude and/or redshift). We undertake extensive Monte Carlo simulations that take into account intergalactic attenuation, stellar population synthesis models, dust extinction, and photometric noise in order to explore the moments of the distribution of the escaping radiation. Various distributions (exponential, log-normal, and Gaussian) are explored. We find that the median f{sub esc} is lower than {approx_equal}6% with an 84% percentile limit not larger than 20%. If this result remains valid for fainter LBGs down to current observational limits, then the LBG population might be not sufficient to account for the entire photoionization budget at the redshifts considered here, with the exact details dependent upon the assumed ionizing background and QSO contribution thereto. It is possible that f{sub esc} depends on the UV luminosity of the galaxies, with fainter galaxies having higher f{sub esc}, and estimates of f{sub esc} from a sample of faint LBGs from HUDF (i{sub 775} {<=}28.5) are in broad quantitative agreement with such a scenario.

  17. Pharmacogenetic Study in Rectal Cancer Patients Treated With Preoperative Chemoradiotherapy: Polymorphisms in Thymidylate Synthase, Epidermal Growth Factor Receptor, GSTP1, and DNA Repair Genes

    SciTech Connect (OSTI)

    Paez, David; Salazar, Juliana; Pare, Laia; Pertriz, Lourdes; Targarona, Eduardo; Rio, Elisabeth del; Barnadas, Agusti; Marcuello, Eugenio; Baiget, Montserrat

    2011-12-01

    Purpose: Several studies have been performed to evaluate the usefulness of neoadjuvant treatment using oxaliplatin and fluoropyrimidines for locally advanced rectal cancer. However, preoperative biomarkers of outcome are lacking. We studied the polymorphisms in thymidylate synthase, epidermal growth factor receptor, glutathione S-transferase pi 1 (GSTP1), and several DNA repair genes to evaluate their usefulness as pharmacogenetic markers in a cohort of 128 rectal cancer patients treated with preoperative chemoradiotherapy. Methods and Materials: Blood samples were obtained from 128 patients with Stage II-III rectal cancer. DNA was extracted from the peripheral blood nucleated cells, and the genotypes were analyzed by polymerase chain reaction amplification and automated sequencing techniques or using a 48.48 dynamic array on the BioMark system. The germline polymorphisms studied were thymidylate synthase, (VNTR/5 Prime UTR, 2R G>C single nucleotide polymorphism [SNP], 3R G>C SNP), epidermal growth factor receptor (Arg497Lys), GSTP1 (Ile105val), excision repair cross-complementing 1 (Asn118Asn, 8092C>A, 19716G>C), X-ray repair cross-complementing group 1 (XRCC1) (Arg194Trp, Arg280His, Arg399Gln), and xeroderma pigmentosum group D (Lys751Gln). The pathologic response, pathologic regression, progression-free survival, and overall survival were evaluated according to each genotype. Results: The Asterisk-Operator 3/ Asterisk-Operator 3 thymidylate synthase genotype was associated with a greater response rate (pathologic complete remission and microfoci residual tumor, 59% in Asterisk-Operator 3/ Asterisk-Operator 3 vs. 35% in Asterisk-Operator 2/ Asterisk-Operator 2 and Asterisk-Operator 2/ Asterisk-Operator 3; p = .013). For the thymidylate synthase genotype, the median progression-free survival was 103 months for the Asterisk-Operator 3/ Asterisk-Operator 3 patients and 84 months for the Asterisk-Operator 2/ Asterisk-Operator 2 and Asterisk-Operator 2/ Asterisk

  18. Low Dose Radiation-Induced Genome and Epigenome Instability Symposium and Epigenetic Mechanisms, DNA Repair, and Chromatin Symposium at the EMS 2008 Annual Meeting - October 2008

    SciTech Connect (OSTI)

    Morgan, William F.; Kovalchuk, Olga; Dolinoy, Dana C.; Dubrova, Yuri E.; Coleman, Matthew A.; Schär, Primo; Pogribny, Igor; Hendzel, Michael

    2010-02-19

    The Low Dose Radiation Symposium thoughtfully addressed ionizing radiation non-mutational but transmissable alterations in surviving cells. Deregulation of epigenetic processes has been strongly implicated in carcinogenesis, and there is increasing realization that a significant fraction of non-targeted and adaptive mechanisms in response to ionizing radiation are likely to be epigenetic in nature. Much remains to be learned about how chromatin and epigenetic regulators affect responses to low doses of radiation, and how low dose radiation impacts other epigenetic processes. The Epigenetic Mechanisms Symposium focused on on epigenetic mechanisms and their interplay with DNA repair and chromatin changes. Addressing the fact that the most well understood mediators of epigenetic regulation are histone modifications and DNA methylation. Low levels of radiation can lead to changes in the methylation status of certain gene promoters and the expression of DNA methyltransferases, However, epigenetic regulation can also involve changes in higher order chromosome structure.

  19. Oxidative DNA damage and repair in children exposed to low levels of arsenic in utero and during early childhood: Application of salivary and urinary biomarkers

    SciTech Connect (OSTI)

    Hinhumpatch, Pantip; Navasumrit, Panida; Chaisatra, Krittinee; Promvijit, Jeerawan; Mahidol, Chulabhorn; Ruchirawat, Mathuros

    2013-12-15

    The present study aimed to assess arsenic exposure and its effect on oxidative DNA damage and repair in young children exposed in utero and continued to live in arsenic-contaminated areas. To address the need for biological specimens that can be acquired with minimal discomfort to children, we used non-invasive urinary and salivary-based assays for assessing arsenic exposure and early biological effects that have potentially serious health implications. Levels of arsenic in nails showed the greatest magnitude of difference between exposed and control groups, followed by arsenic concentrations in saliva and urine. Arsenic levels in saliva showed significant positive correlations with other biomarkers of arsenic exposure, including arsenic accumulation in nails (r = 0.56, P < 0.001) and arsenic concentration in urine (r = 0.50, P < 0.05). Exposed children had a significant reduction in arsenic methylation capacity indicated by decreased primary methylation index and secondary methylation index in both urine and saliva samples. Levels of salivary 8-OHdG in exposed children were significantly higher (? 4-fold, P < 0.01), whereas levels of urinary 8-OHdG excretion and salivary hOGG1 expression were significantly lower in exposed children (? 3-fold, P < 0.05), suggesting a defect in hOGG1 that resulted in ineffective cleavage of 8-OHdG. Multiple regression analysis results showed that levels of inorganic arsenic (iAs) in saliva and urine had a significant positive association with salivary 8-OHdG and a significant negative association with salivary hOGG1 expression. - Highlights: The effects of arsenic exposure in utero and through early childhood were studied. Arsenic-exposed children had a reduction in arsenic methylation capacity. Exposed children had more DNA damage, observed as elevated salivary 8-OHdG. Lower salivary hOGG1 in exposed children indicated impairment of 8-OHdG repair. Salivary and urinary 8-OHdG levels were discordant.

  20. ICAP (International Code Assessment and Applications Program) assessment of RELAP5/MOD2, Cycle 36. 05 against LOFT (Loss of Fluid Test) Small Break Experiment L3-7

    SciTech Connect (OSTI)

    Lee, Euy-Joon; Chung, Bud-Dong; Kim, Hho-Jung . Korea Nuclear Safety Center)

    1990-04-01

    The LOFT small break (1 in-dia) experiment L3-7 has been analyzed using the reactor thermal hydraulic analysis code RELAP5/MOD2, Cycle 36.05. The base calculation (Case A) was completed and compared with the experimental data. Three types of sensitivity studies (Cases B, Cm, and D) were carried out to investigate the effects of (1) break discharge coefficient Cd, (2) pump two-phase difference multiplier and (3) High Pressure Injection System (HPIS) capacity on major thermal and hydraulic (T/H) parameters. A nodalization study (Case E) was conducted to assess the phenomena with a simplified nodalization. The results indicate that Cd of 0.9 and 0.1 fit to the single discharge flow rate of Test L3-7 best among the tried cases. The pump two-phase multiplier has little effects on the T/H parameters because of the low discharge flow rate and the early pump coast down in this smaller size SBLOCA. But HPIS capacity has a very strong influence on parameters such as pressure, flow and temperature. It is also shown that a simplified nodalization could accomodate the dominant T/H phenomena with the same degree of code accuracy and efficiency.