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Sample records for alkyltransferase agt repairs

  1. Recombinant human O6-alkylguanine-DNA alkyltransferase (AGT), Cys145-alkylated AGT and Cys145 --> Met145 mutant AGT: comparison by isoelectric focusing, CD and time-resolved fluorescence spectroscopy.

    PubMed Central

    Federwisch, M; Hassiepen, U; Bender, K; Dewor, M; Rajewsky, M F; Wollmer, A

    1997-01-01

    Isoelectric focusing, CD, steady-state and time-resolved fluorescence spectroscopy were used to compare the native recombinant human DNA-repair protein O6-alkylguanine-DNA alkyltransferase (AGT) with AGT derivatives methylated or benzylated on Cys145 or modified by site-directed mutagenesis at the active centre (Met145 mutant). The AGT protein is approximately spherical with highly constrained Trp residues, but is not stabilized by disulphide bridges. In contrast with native AGT, alkylated AGT precipitated at 25 degrees C but remained monomeric at 4 degrees C. As revealed by isoelectric focusing, pI changed from 8.2 (AGT) to 8. 4 (Cys145-methylated AGT) and 8.6 (Cys145-benzylated AGT). The alpha-helical content of the Met145 mutant was decreased by approx. 5% and Trp residues were partially liberated. Although non-covalent binding of O6-benzylguanine did not alter the secondary structure of AGT, its alpha-helical content was increased by approx. 2% on methylation and by approx. 4% on benzylation, altogether indicating a small conformational change in AGT on undergoing alkylation. No signal sequences have been found in AGT that mark it for polyubiquitination. Therefore the signal for AGT degradation remains to be discovered. PMID:9164873

  2. Repair of O6-methylguanine adducts in human telomeric G-quadruplex DNA by O6-alkylguanine-DNA alkyltransferase

    PubMed Central

    Hellman, Lance M.; Spear, Tyler J.; Koontz, Colton J.; Melikishvili, Manana; Fried, Michael G.

    2014-01-01

    O6-alkylguanine-DNA alkyltransferase (AGT) is a single-cycle DNA repair enzyme that removes pro-mutagenic O6-alkylguanine adducts from DNA. Its functions with short single-stranded and duplex substrates have been characterized, but its ability to act on other DNA structures remains poorly understood. Here, we examine the functions of this enzyme on O6-methylguanine (6mG) adducts in the four-stranded structure of the human telomeric G-quadruplex. On a folded 22-nt G-quadruplex substrate, binding saturated at 2 AGT:DNA, significantly less than the ∼5 AGT:DNA found with linear single-stranded DNAs of similar length, and less than the value found with the telomere sequence under conditions that inhibit quadruplex formation (4 AGT:DNA). Despite these differences, AGT repaired 6mG adducts located within folded G-quadruplexes, at rates that were comparable to those found for a duplex DNA substrate under analogous conditions. Repair was kinetically biphasic with the amplitudes of rapid and slow phases dependent on the position of the adduct within the G-quadruplex: in general, adducts located in the top or bottom tetrads of a quadruplex stack exhibited more rapid-phase repair than did adducts located in the inner tetrad. This distinction may reflect differences in the conformational dynamics of 6mG residues in G-quadruplex DNAs. PMID:25080506

  3. DNA binding, nucleotide flipping, and the helix-turn-helix motif in base repair by O6-alkylguanine-DNA alkyltransferase and its implications for cancer chemotherapy

    PubMed Central

    Tubbs, Julie L.; Pegg, Anthony E.; Tainer, John A.

    2007-01-01

    O6-alkylguanine-DNA alkyltransferase (AGT) is a crucial target both for the prevention of cancer and for chemotherapy, since it repairs mutagenic lesions in DNA, and it limits the effectiveness of alkylating chemotherapies. AGT catalyzes the unique, single-step, direct damage reversal repair of O6-alkylguanines by selectively transferring the O6-alkyl adduct to an internal cysteine residue. Recent crystal structures of human AGT alone and in complex with substrate DNA reveal a two-domain a/β fold and a bound zinc ion. AGT uses its helix-turn-helix motif to bind substrate DNA via the minor groove. The alkylated guanine is then flipped out from the base stack into the AGT active site for repair by covalent transfer of the alkyl adduct to Cys145. An asparagine hinge (Asn137) couples the helix-turn-helix DNA binding and active site motifs. An arginine finger (Arg128) stabilizes the extrahelical DNA conformation. With this newly improved structural understanding of AGT and its interactions with biologically relevant substrates, we can now begin to unravel the role it plays in preserving genetic integrity and discover how it promotes resistance to anticancer therapies. PMID:17485252

  4. Mutagenicity associated with O6-methylguanine-DNA damage and mechanism of nucleotide flipping by AGT during repair

    NASA Astrophysics Data System (ADS)

    Jena, N. R.; Bansal, Manju

    2011-08-01

    Methylated guanine damage at O6 position (i.e. O6MG) is dangerous due to its mutagenic and carcinogenic character that often gives rise to G:C-A:T mutation. However, the reason for this mutagenicity is not known precisely and has been a matter of controversy. Further, although it is known that O6-alkylguanine-DNA alkyltransferase (AGT) repairs O6MG paired with cytosine in DNA, the complete mechanism of target recognition and repair is not known completely. All these aspects of DNA damage and repair have been addressed here by employing high level density functional theory in gas phase and aqueous medium. It is found that the actual cause of O6MG mediated mutation may arise due to the fact that DNA polymerases incorporate thymine opposite to O6MG, misreading the resulting O6MG:T complex as an A:T base pair due to their analogous binding energies and structural alignments. It is further revealed that AGT mediated nucleotide flipping occurs in two successive steps. The intercalation of the finger residue Arg128 into the DNA double helix and its interaction with the O6MG:C base pair followed by rotation of the O6MG nucleotide are found to be crucial for the damage recognition and nucleotide flipping.

  5. Synthesis and characterization of an O(6)-2'-deoxyguanosine-alkyl-O(6)-2'-deoxyguanosine interstrand cross-link in a 5'-GNC motif and repair by human O(6)-alkylguanine-DNA alkyltransferase.

    PubMed

    McManus, Francis P; Fang, Qingming; Booth, Jason D M; Noronha, Anne M; Pegg, Anthony E; Wilds, Christopher J

    2010-10-07

    O(6)-2'-Deoxyguanosine-alkyl-O(6)-2'-deoxyguanosine interstrand DNA cross-links (ICLs) with a four and seven methylene linkage in a 5'-GNC- motif have been synthesized and their repair by human O6-alkylguanine-DNA alkyltransferase (hAGT) investigated. Duplexes containing 11 base-pairs with the ICLs in the center were assembled by automated DNA solid-phase synthesis using a cross-linked 2'-deoxyguanosine dimer phosphoramidite, prepared via a seven step synthesis which employed the Mitsunobu reaction to introduce the alkyl lesion at the O(6) atom of guanine. Introduction of the four and seven carbon ICLs resulted in no change in duplex stability based on UV thermal denaturation experiments compared to a non-cross-linked control. Circular dichroism spectra of these ICL duplexes exhibited features of a B-form duplex, similar to the control, suggesting that these lesions induce little overall change in structure. The efficiency of repair by hAGT was examined and it was shown that hAGT repairs both ICL containing duplexes, with the heptyl ICL repaired more efficiently relative to the butyl cross-link. These results were reproducible with various hAGT mutants including one that contains a novel V148L mutation. The ICL duplexes displayed similar binding affinities to a C145S hAGT mutant compared to the unmodified duplex with the seven carbon containing ICLs displaying slightly higher binding. Experiments with CHO cells to investigate the sensitivity of these cells to busulfan and hepsulfam demonstrate that hAGT reduces the cytotoxicity of hepsulfam suggesting that the O(6)-2'-deoxyguanosine-alkyl-O(6)-2'-deoxyguanosine interstrand DNA cross-link may account for at least part of the cytotoxicity of this agent.

  6. Insight into the cooperative DNA binding of the O⁶-alkylguanine DNA alkyltransferase.

    PubMed

    Tessmer, Ingrid; Fried, Michael G

    2014-08-01

    The O(6)-alkylguanine DNA alkyltransferase (AGT) is a highly conserved protein responsible for direct repair of alkylated guanine and to a lesser degree thymine bases. While specific DNA lesion-bound complexes in crystal structures consist of monomeric AGT, several solution studies have suggested that cooperative DNA binding plays a role in the physiological activities of AGT. Cooperative AGT-DNA complexes have been described by theoretical models, which can be tested by atomic force microscopy (AFM). Direct access to structural features of AGT-DNA complexes at the single molecule level by AFM imaging revealed non-specifically bound, cooperative complexes with limited cluster length. Implications of cooperative binding in AGT-DNA interactions are discussed.

  7. Effect of O6-Alkylguanine-DNA Alkyltransferase on Genotoxicity of Epihalohydrins

    PubMed Central

    Kalapila, Aley G.; Loktionova, Natalia A.; Pegg, Anthony E.

    2010-01-01

    The effect of O6-alkylguanine-DNA alkyltransferase (AGT) on the toxicity and mutagenicity of epihalohydrins was studied. AGT is a DNA repair protein that protects cells from agents that produce genotoxic O6-alkylguanine lesions by transferring the alkyl group to an internal cysteine residue (Cys145 in human AGT) in a single-step. This cysteine acceptor site is highly reactive and epihalohydrins reacted readily with AGT at this site with a halide order of reactivity of Br > Cl > F. AGT expression in bacterial cells caused a very large increase in the mutagenicity and cytotoxicity of epibromohydrin. The mutations were almost all G:C to A:T transitions. Epichlorohydrin also augmented AGT-mediated mutagenesis but to a lesser extent than epibromohydrin. In vitro experiments showed that AGT was covalently cross-linked to DNA in the presence of epibromohydrin and that this conjugation occurred predominantly at Cys145, and to a smaller extent at Cys150, a less reactive residue also located within the active site pocket. Two pathways yielding the AGT-DNA adduct were found to occur. The predominant mechanism results in an AGT-epihalohydrin intermediate, which, facilitated by the DNA binding properties of AGT, then reacts covalently with DNA. The second pathway involves an initial reactive DNA-epihalohydrin intermediate that subsequently reacts with AGT. Our results show that the paradoxical AGT-mediated increase in genotoxicity which has previously been shown to occur with dihaloalkanes, butadiene diepoxide and nitrogen mustards, also occurs with epihalohydrins and is likely to contribute to their toxicity and mutagenicity. PMID:19472322

  8. Specific labeling of O6-alkylguanine-DNA alkyltransferase by reaction with O6-(p-hydroxy[3H]methylbenzyl)guanine.

    PubMed

    Ciocco, G M; Moschel, R C; Chae, M Y; McLaughlin, P J; Zagon, I S; Pegg, A E

    1995-09-15

    O6-Alkylguanine-DNA alkyltransferase (AGT) is an important DNA repair protein that removes adducts from the O6 position of guanine by transferring them to a cysteine residue within its amino acid sequence. Mammalian AGTs are readily inactivated by incubation with O6-benzyl-guanine (BG), which is an alternative substrate for the protein. To examine this inactivation in more detail and to develop a procedure for the specific labeling of human AGT, we synthesized a BG derivative, O6-(p-hydroxy[3H]methylbenzyl_guanine ([3H]HMBG) and examined its interaction with AGT in HT29 cell extracts and in HT29 cells. Incubation of human AGT with [3H]HMBG led to the incorporation of radioactivity in the protein in a time- and temperature-dependent manner. This reaction was specific, since neither AGT that was first inactivated by reaction with BG nor proteins other than AGT were labeled. Digestion of the labeled AGT with trypsin showed that a single peptide contained the label. Sequencing of this peptide indicated that the label was bound to cysteine-145. These results demonstrate that AGT accepts HMBG as a substrate and becomes inactivated by transfer of a p-hydroxymethylbenzyl residue to the cysteine-145 acceptor site. When [3H]HMBG was added to cultures of HT29 cells which are Mer+ and express active AGT, radioactivity was incorporated in a macromolecule and could be detected by autoradiography. No such labeling occurred with BE or CHO cells, which are Mer- and lack AGT. Examination of the interaction of [3H]HMBG with mutant AGT proteins that differ greatly in their abilities to react with BG showed that there was a strong correlation between the reaction with BG and the labeling with [3H]HMBG. These results indicate that [3H]HMBG is a potentially useful reagent for the detection and localization of AGT activity and for the investigation of its mechanism of action.

  9. Measurement of O(6)-alkylguanine-DNA alkyltransferase activity in tumour cells using stable isotope dilution HPLC-ESI-MS/MS.

    PubMed

    Sun, Guohui; Zhao, Lijiao; Fan, Tengjiao; Ren, Ting; Zhong, Rugang

    2016-10-15

    The repair of DNA mediated by O(6)-alkylguanine-DNA alkyltransferase (AGT) provides protection against DNA damage from endogenous or exogenous alkylation of the O(6) position of guanine. However, this repair acts as a double-edged sword in cancer treatment, as it not only protects normal cells from chemotherapy-associated toxicities, but also results in cancer cell resistance to guanine O(6)-alkylating antitumour agents. Thus, AGT plays an important role in predicting the individual susceptibility to guanine O(6)-alkylating carcinogens and chemotherapies. Accordingly, it is necessary to establish a quantitative method for determining AGT activity with high accuracy, sensitivity and practicality. Here, we describe a novel nonradioactive method for measuring AGT activity using stable isotope dilution high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). This method is based on the irreversibility of the removal of the O(6)-alkyl group from guanine by AGT and on the high affinity of O(6)-benzylguanine (O(6)-BG) as an AGT substrate. HPLC-ESI-MS/MS was used to measure the AGT activities in cell protein extracts from eight tumour lines, demonstrating that AGT activity was quite variable among different cell lines, ranging from nondetectable to 1021 fmol/mg protein. The experiments performed in intact tumour cells yielded similar results but exhibited slightly higher activities than those observed in cell protein extracts. The accuracy of this method was confirmed by an examination of AGT expression levels using western blotting analysis. To our knowledge, this method is the first mass spectrometry-based AGT activity assay, and will likely provide assistance in the screening of cancer risk or the application of chemotherapies.

  10. Improved Fermentation Performance of a Lager Yeast after Repair of Its AGT1 Maltose and Maltotriose Transporter Genes▿ †

    PubMed Central

    Vidgren, Virve; Huuskonen, Anne; Virtanen, Hannele; Ruohonen, Laura; Londesborough, John

    2009-01-01

    The use of more concentrated, so-called high-gravity and very-high-gravity (VHG) brewer's worts for the manufacture of beer has economic and environmental advantages. However, many current strains of brewer's yeasts ferment VHG worts slowly and incompletely, leaving undesirably large amounts of maltose and especially maltotriose in the final beers. α-Glucosides are transported into Saccharomyces yeasts by several transporters, including Agt1, which is a good carrier of both maltose and maltotriose. The AGT1 genes of brewer's ale yeast strains encode functional transporters, but the AGT1 genes of the lager strains studied contain a premature stop codon and do not encode functional transporters. In the present work, one or more copies of the AGT1 gene of a lager strain were repaired with DNA sequence from an ale strain and put under the control of a constitutive promoter. Compared to the untransformed strain, the transformants with repaired AGT1 had higher maltose transport activity, especially after growth on glucose (which represses endogenous α-glucoside transporter genes) and higher ratios of maltotriose transport activity to maltose transport activity. They fermented VHG (24° Plato) wort faster and more completely, producing beers containing more ethanol and less residual maltose and maltotriose. The growth and sedimentation behaviors of the transformants were similar to those of the untransformed strain, as were the profiles of yeast-derived volatile aroma compounds in the beers. PMID:19181838

  11. Repair of O6-G-alkyl-O6-G interstrand cross-links by human O6-alkylguanine-DNA alkyltransferase†

    PubMed Central

    Fang, Qingming; Noronha, Anne M.; Murphy, Sebastian P.; Wilds, Christopher J.; Tubbs, Julie L.; Tainer, John A.; Chowdhury, Goutam; Guengerich, F. Peter; Pegg, Anthony E.

    2008-01-01

    O6-Alkylguanine-DNA alkyltransferase (AGT) plays an important role protecting cells from alkylating agents. This reduces carcinogenesis and mutagenesis initiated by such agents but AGT also provides a major resistance mechanism to some chemotherapeutic drugs. In order to improve understanding of the AGT-mediated repair reaction and to increase understanding of the spectrum of repairable damage, we have studied the ability of AGT to repair interstrand cross-link DNA damage where the two DNA strands are joined via the guanine-O6 in each strand. An oligodeoxyribonucleotide containing a heptane cross-link was repaired with initial formation of an AGT-oligo complex and further reaction of a second AGT molecule yielding a hAGT dimer and free oligo. However, an oligodeoxyribonucleotide with a butane cross-link was a very poor substrate for AGT-mediated repair and only the first reaction to form an AGT-oligo complex could be detected. Models of the reaction of these substrates in the AGT active site show that the DNA duplex is forced apart locally to repair the first guanine. This reaction is greatly hindered with the butane cross-link, which is mostly buried in the active site pocket and limited in conformational flexibility. This limitation also prevents the adoption of a conformation for the second reaction to repair the AGT-oligo complex. These results are consistent with the postulated mechanism of AGT repair that involves DNA binding and flipping of the substrate nucleotide and indicate that hAGT can repair some types of interstrand cross-link damages. PMID:18803403

  12. Expression of mammalian O6-alkylguanine-DNA alkyltransferase in a cell line sensitive to alkylating agents.

    PubMed

    Dolan, M E; Norbeck, L; Clyde, C; Hora, N K; Erickson, L C; Pegg, A E

    1989-09-01

    Chinese hamster ovary cells (CHO) were co-transfected with pSV2neo and sheared DNA from either a human cell line (HT29) expressing high levels of O6-alkylguanine-DNA alkyltransferase (AGT) or from a cell line (BE) deficient in this activity. Cells expressing the selectable marker were obtained by exposure to G418 and colonies resistant to alkylation damage isolated by growth in the presence of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU). The number of colonies of cells expressing AGT activity arising after transfection with DNA from BE cells was similar to the number arising from cells exposed to HT29 DNA. Although the amount of AGT repair protein expressed in the transfectant colonies from this experiment was relatively low, these results indicate that repair of alkylation damage can be restored in AGT-deficient cells by transfection of human DNA from both repair-deficient and proficient cells. A separate transfection of CHOMG cells [a mutant of CHO cells resistant to the drug, methylglyoxal bis(guanylhydrazone) (MGBG)] with HT29 DNA and pSV2neo followed by selection of G418 and 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) resulted in three colonies with high AGT levels. These transfectants had different growth rates and expressed levels of the AGT protein between 230 and 300 fmol/mg protein. The transfectants were as resistant to the cytotoxic effects of BCNU, Clomesone, methylnitrosourea (MNU) and 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) as HT29 cells which were much more resistant than the parental CHOMG cells. Pretreatment of transfectant cells with 0.4 mM O6-methylguanine for 24 h reduced AGT activity to 14% basal levels, which upon removal of the base increased to approximately 74% basal level within 8 h. The sensitivity to the cytotoxic effects of both the chloroethylating and methylating agents was enhanced by treatment with O6-methylguanine. In the same manner, the number of BCNU-induced DNA interstrand cross-links increased in transfectant

  13. Influence of the Expression Level of O6-Alkylguanine-DNA Alkyltransferase on the Formation of DNA Interstrand Crosslinks Induced by Chloroethylnitrosoureas in Cells: A Quantitation Using High-Performance Liquid Chromatography-Mass Spectrometry

    PubMed Central

    Sun, Guohui; Peng, Ruizeng; Zhao, Lijiao; Zhong, Rugang

    2015-01-01

    Chloroethylnitrosoureas (CENUs), which are bifunctional alkylating agents widely used in the clinical treatment of cancer, exert anticancer activity by inducing crosslink within a guanine-cytosine DNA base pair. However, the formation of dG-dC crosslinks can be prevented by O6-alkylguanine-DNA alkyltransferase (AGT), ultimately leading to drug resistance. Therefore, the level of AGT expression is related to the formation of dG-dC crosslinks and the sensitivity of cells to CENUs. In this work, we determined the CENU-induced dG-dC crosslink in mouse L1210 leukemia cells and in human glioblastoma cells (SF-763, SF-767 and SF-126) containing different levels of AGT using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry. The results indicate that nimustine (ACNU) induced more dG-dC crosslinks in L1210 leukemia cells than those induced by carmustine (BCNU), lomustine (CCNU) and fotemustine (FTMS). This result was consistent with a previously reported cohort study, which demonstrated that ACNU had a better survival gain than BCNU, CCNU and FTMS for patients with high-grade glioma. Moreover, we compared the crosslinking levels and the cytotoxicity in SF-763, SF-767 and SF-126 cells with different AGT expression levels after exposure to ACNU. The levels of dG-dC crosslink in SF-126 cells (low AGT expression) were significantly higher than those in SF-767 (medium AGT expression) and SF-763 (high AGT expression) cells at each time point. Correspondingly, the cytotoxicity of SF-126 was the highest followed by SF-767 and SF-763. The results obtained in this work provided unequivocal evidence for drug resistance to CENUs induced by AGT-mediated repair of DNA ICLs. We postulate that the level of dG-dC crosslink has the potential to be employed as a biomarker for estimating drug resistance and anticancer efficiencies of novel CENU chemotherapies. PMID:25799182

  14. Alkyltransferase-mediated Toxicity of 1,3-Butadiene Diepoxide

    PubMed Central

    Kalapila, Aley G.; Loktionova, Natalia A.; Pegg, Anthony E.

    2008-01-01

    Human O6-alkylguanine-DNA alkyltransferase (hAGT) expression increases mutations and cytotoxicity following exposure to 1,3-butadiene diepoxide (BDO) and hAGT-DNA cross-links are formed in the presence of BDO. We have used hAGT mutants to investigate the mechanism of cross-link formation and genotoxicity. Formation of a hAGT-DNA conjugate in vitro was observed with C145S and C145A mutant proteins but was considerably diminished with the C145A/C150S double mutant confirming that cross-linking primarily involves either of these two cysteine residues, which are located in the active site pocket of the protein. Cross-link formation by BDO occurred both via (a) an initial reaction of BDO with hAGT followed by attack of the reactive hAGT complex on DNA, and (b) the initial reaction of BDO with DNA followed by a reaction between hAGT and the DNA adduct. These results differ from those with 1,2-dibromoethane (DBE) where Cys145 is the only site of attachment and pathway (b) does not occur. The complex formed between hAGT at Cys145 and BDO was very unstable in aqueous solution. However, the BDO-hAGT complex at Cys150 exhibited stability for more than 1 h. The effect of hAGT and mutants on BDO-induced genotoxicity was studied in E. coli using the forward assay to rifampicin resistance. Both mutations and cell killing were greatly increased by wild type hAGT and there was a smaller but significant effect with the C145A mutant. The R128A mutant and R128A/C145A and C145A/C150S double mutants were ineffective supporting the hypothesis that the formation of hAGT-DNA cross-links is responsible for the enhanced genotoxicity detected in this biological system. In the absence of hAGT, there were equal proportions of G:C to A:T transitions, G:C to T:A transversions and A:T to T:A transversions. Wild type hAGT expression yielded significantly greater G:C to A:T and A:T to G:C transitions, whereas C145A mutant expression resulted in more transitions and transversions at A:T base

  15. DNA-protein crosslinks processed by nucleotide excision repair and homologous recombination with base and strand preference in E. coli model system.

    PubMed

    Fang, Qingming

    2013-01-01

    Bis-electrophiles including dibromoethane and epibromohydrin can react with O(6)-alkylguanine-DNA alkyltransferase (AGT) and form AGT-DNA crosslinks in vitro and in vivo. The presence of human AGT (hAGT) paradoxically increases the mutagenicity and cytotoxicity of bis-electrophiles in cells. Here we establish a bacterial system to study the repair mechanism and cellular responses to DNA-protein crosslinks (DPCs) in vivo. Results show that both nucleotide excision repair (NER) and homologous recombination (HR) pathways can process hAGT-DNA crosslinks with HR playing a dominant role. Mutation spectra show that HR has no strand preference but NER favors processing of the DPCs in the transcribed strand; UvrA, UvrB and Mfd can interfere with small size DPCs but only UvrA can interfere with large size DPCs in the transcribed strand processed by HR. Further, we found that DPCs at TA deoxynucleotide sites are very inefficiently processed by NER and the presence of NER can interfere with these DNA lesions processed by HR. These data indicate that NER and HR can process DPCs cooperatively and competitively and NER processes DPCs with base and strand preference. Therefore, the formation of hAGT-DNA crosslinks can be a plausible and specific system to study the repair mechanism and effects of DPCs precisely in vivo.

  16. O6-3-[131I]iodobenzylguanine: improved synthesis and further evaluation of a potential agent for imaging of alkylguanine-DNA alkyltransferase.

    PubMed

    Vaidyanathan, Ganesan; Affleck, Donna J; Norman, Joseph; Welsh, Phil; Liu, Wenge; Johnson, Stewart P; Friedman, Henry S; Zalutsky, Michael R

    2004-01-01

    O(6)-Benzylguanine derivatives with suitable radionuclides attached to the benzyl ring are potentially useful in the noninvasive imaging of the DNA repair protein, alkylguanine-DNA alkyltransferase (AGT). Previously, O(6)-3-[(131)I]iodobenzylguanine ([(131)I]IBG) was prepared using a two-step approach; we now report its synthesis in a single step by the radioiododestannylation of O(6)-3-(trimethylstannyl)benzylguanine in 85-95% radiochemical yield. The in vitro specific uptake of [(131)I]IBG in DAOY human medulloblastoma cells, in TE-671 human rhabdomyosarcoma cells and a CHO cell line transfected to express AGT was linear (r(2) = 0.9-1.0) as a function of cell density. After intravenous injection of [(131)I]IBG in athymic mice bearing TE-671 xenografts, tumor uptake was 1.38 +/- 0.34% ID/g at 0.5 h and declined at 2 and 4 h. Preadministration of O(6)-(3-iodobenzyl)guanine (IBG) at 0.5 h increased uptake not only in tumor but also in several normal tissues. Notable exceptions were thyroid (p < 0.05), lung (p <0.05) and stomach. After intratumoral injection of [(131)I]IBG in the same xenograft model, the uptake in tumors that were depleted of AGT by BG treatment (165.8 +/- 27.5% ID/g) was about 60% of that in control mice (272.4 +/- 48.2% ID/g; p < 0.05).

  17. TOPOLOGIES OF COMPLEXES CONTAINING O6-ALKYLGUANINE-DNA ALKYLTRANSFERASE AND DNA

    PubMed Central

    Adams, Claire A.; Melikishvili, Manana; Rodgers, David W.; Rasimas, Joseph J.; Pegg, Anthony E.; Fried, Michael G.

    2009-01-01

    SUMMARY The mutagenic and cytotoxic effects of many alkylating agents are reduced by O6-alkylguanine-DNA alkyltransferase (AGT). In humans this protein protects the integrity of the genome, but also contributes to the resistance of tumors to DNA-alkylating chemotherapeutic agents. Here we describe and test models for cooperative multi-protein complexes of AGT with single-stranded and duplex DNAs that are based on in vitro binding data and the crystal structure of a 1:1 AGT-DNA complex. These models predict that cooperative assemblies contain a 3-start helical array of proteins with dominant protein-protein interactions between the amino-terminal face of protein n and the carboxy-terminal face of protein n + 3, and they predict that binding duplex DNA does not require large changes in B-form DNA geometry. Experimental tests using protein crosslinking analyzed by mass spectrometry, electrophoretic and analytical ultracentrifugation binding assays and topological analyses with closed circular DNA show that the properties of multiprotein AGT-DNA complexes are consistent with these predictions. PMID:19358853

  18. Host determinants of DNA alkylation and DNA repair activity in human colorectal tissue: O(6)-methylguanine levels are associated with GSTT1 genotype and O(6)-alkylguanine-DNA alkyltransferase activity with CYP2D6 genotype.

    PubMed

    Povey, A C; Hall, C N; Badawi, A F; Cooper, D P; Guppy, M J; Jackson, P E; O'Connor, P J; Margison, G P

    2001-08-22

    There is increasing evidence that alkylating agent exposure may increase large bowel cancer risk and factors which either alter such exposure or its effects may modify risk. Hence, in a cross-sectional study of 78 patients with colorectal disease, we have examined whether (i) metabolic genotypes (GSTT1, GSTM1, CYP2D6, CYP2E1) are associated with O(6)-methyldeoxyguanosine (O(6)-MedG) levels, O(6)-alkylguanine-DNA alkyltransferase (ATase) activity or K-ras mutations, and (ii) there was an association between ATase activity and O(6)-MedG levels. Patients with colon tumours and who were homozygous GSTT1(*)2 genotype carriers were more likely than patients who expressed GSTT1 to have their DNA alkylated (83 versus 32%, P=0.03) and to have higher O(6)-MedG levels (0.178+/-0.374 versus 0.016+/-0.023 micromol O(6)-MedG/mol dG, P=0.04) in normal, but not tumour, DNA. No such association was observed between the GSTT1 genotype and the frequency of DNA alkylation or O(6)-MedG levels in patients with benign colon disease or rectal tumours. Patients with colon tumours or benign colon disease who were CYP2D6-poor metabolisers had higher ATase activity in normal tissue than patients who were CYP2D6 extensive metabolisers or CYP2D6 heterozygotes. Patients with the CYP2E1 Dra cd genotype were less likely to have a K-ras mutation: of 55 patients with the wild-type CYP2E1 genotype (dd), 23 had K-ras mutations, whereas none of the 7 individuals with cd genotype had a K-ras mutation (P=0.04). No other associations were observed between GSTT1, GSTM1, CYP2D6 and CYP2E1 Pst genotypes and adduct levels, ATase activity or mutational status. O(6)-MedG levels were not associated with ATase activity in either normal or tumour tissue. However, in 15 patients for whom both normal and tumour DNA contained detectable O(6)-MedG levels, there was a strong positive association between the normal DNA/tumour DNA adduct ratio and the normal tissue/tumour tissue ATase ratio (r(2)=0.66, P=0.001). These

  19. Structure-function relationships governing activity and stability of a DNA alkylation damage repair thermostable protein.

    PubMed

    Perugino, Giuseppe; Miggiano, Riccardo; Serpe, Mario; Vettone, Antonella; Valenti, Anna; Lahiri, Samarpita; Rossi, Franca; Rossi, Mosè; Rizzi, Menico; Ciaramella, Maria

    2015-10-15

    Alkylated DNA-protein alkyltransferases repair alkylated DNA bases, which are among the most common DNA lesions, and are evolutionary conserved, from prokaryotes to higher eukaryotes. The human ortholog, hAGT, is involved in resistance to alkylating chemotherapy drugs. We report here on the alkylated DNA-protein alkyltransferase, SsOGT, from an archaeal species living at high temperature, a condition that enhances the harmful effect of DNA alkylation. The exceptionally high stability of SsOGT gave us the unique opportunity to perform structural and biochemical analysis of a protein of this class in its post-reaction form. This analysis, along with those performed on SsOGT in its ligand-free and DNA-bound forms, provides insights in the structure-function relationships of the protein before, during and after DNA repair, suggesting a molecular basis for DNA recognition, catalytic activity and protein post-reaction fate, and giving hints on the mechanism of alkylation-induced inactivation of this class of proteins.

  20. AGT100 turbomachinery. [for automobiles

    NASA Technical Reports Server (NTRS)

    Tipton, D. L.; Mckain, T. F.

    1982-01-01

    High-performance turbomachinery components have been designed and tested for the AGT100 automotive engine. The required wide range of operation coupled with the small component size, compact packaging, and low cost of production provide significant aerodynamic challenges. Aerodynamic design and development testing of the centrifugal compressor and two radial turbines are described. The compressor achieved design flow, pressure ratio, and surge margin on the initial build. Variable inlet guide vanes have proven effective in modulating flow capacity and in improving part-speed efficiency. With optimum use of the variable inlet guide vanes, the initial efficiency goals have been demonstrated in the critical idle-to-70% gasifier speed range. The gasifier turbine exceeded initial performance goals and demonstrated good performance over a wide range. The radial power turbine achieved 'developed' efficiency goals on the first build.

  1. Depletion of mammalian O6-alkylguanine-DNA alkyltransferase activity by O6-benzylguanine provides a means to evaluate the role of this protein in protection against carcinogenic and therapeutic alkylating agents.

    PubMed Central

    Dolan, M E; Moschel, R C; Pegg, A E

    1990-01-01

    O6-Alkylguanine-DNA alkyltransferase was rapidly and irreversibly inactivated by exposure to O6-benzylguanine or the p-chlorobenzyl and p-methylbenzyl analogues. This inactivation was much more rapid than with O6-methylguanine: incubation with 2.5 microM O6-benzylguanine led to more than a 90% loss of activity within 10 min, whereas 0.2 mM O6-methylguanine for 60 min was required for the same reduction. O6-Benzylguanine was highly effective in depleting the alkyltransferase activity of cultured human colon tumor (HT29) cells. Complete loss of activity was produced within 15 min after addition of O6-benzylguanine to the culture medium and a maximal effect was obtained with 5 microM. In contrast, at least 100 microM O6-methylguanine for 4 hr was needed to get a maximal effect, and this reduced the alkyltransferase by only 80%. Pretreatment of HT29 cells with 10 microM O6-benzylguanine for 2 hr led to a dramatic increase in the cytotoxicity produced by the chemotherapeutic agents 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) or 2-chloroethyl(methysulfonyl)methanesulfonate (Clomesone). Administration of O6-benzylguanine to mice at a dose of 10 mg/kg reduced alkyltransferase levels by more than 95% in both liver and kidney. These results indicate that depletion of the alkyltransferase by O6-benzylguanine may be used to investigate the role of the DNA repair protein in carcinogenesis and mutagenesis and that this treatment may be valuable to increase the chemotherapeutic effectiveness of chloroethylating agents. PMID:2164681

  2. Advanced Gas Turbine (AGT) technology development project

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This report is the final in a series of Technical Summary Reports for the Advanced Gas Turbine (AGT) Technology Development Project, authorizrd under NASA Contract DEN3-167 and sponsored by the DOE. The project was administered by NASA-Lewis Research Center of Cleveland, Ohio. Plans and progress are summarized for the period October 1979 through June 1987. This program aims to provide the US automotive industry the high risk, long range technology necessary to produce gas turbine engines for automobiles that will reduce fuel consumption and reduce environmental impact. The intent is that this technology will reach the marketplace by the 1990s. The Garrett/Ford automotive AGT was designated AGT101. The AGT101 is a 74.5 kW (100 shp) engine, capable of speeds to 100,000 rpm, and operates at turbine inlet temperatures to 1370 C (2500 F) with a specific fuel consumption level of 0.18 kg/kW-hr (0.3 lbs/hp-hr) over most of the operating range. This final report summarizes the powertrain design, power section development and component/ceramic technology development.

  3. AGT 100 automotive gas turbine system development

    NASA Technical Reports Server (NTRS)

    Helms, H. E. G.

    1982-01-01

    General Motors is developing an automotive gas turbine system that can be an alternate powerplant for future automobiles. Work sponsored by DOE and administered by NASA Lewis Research Center is emphasizing small component aerodynamics and high-temperature structural ceramics. Reliability requirements of the AGT 100 turbine system include chemical and structural ceramic component stability in the gas turbine environment. The power train system, its configuration and schedule are presented, and its performance tested. The aerodynamic component development is reviewed with discussions on the compressor, turbine, regenerator, interturbine duct and scroll, and combustor. Ceramic component development is also reviewed, and production cost and required capital investment are taken into consideration.

  4. Advanced Gas Turbine (AGT) powertrain system development for automotive applications

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Topics covered include the AGT 101 engine test; compressor design modification; cold air turbine testing; Mod 1 alloy turbine rotor fabrication; combustion aspects; regenerator development; and thermal screening tests for ceramic materials. The foil gas bearings, rotor dynamics, and AGT controls and accessories are also considered.

  5. AGT and the Segal-Sugawara construction

    NASA Astrophysics Data System (ADS)

    Carlsson, Erik

    2017-01-01

    The conjectures of Alday et al. [Lett. Math. Phys. 91, 167-197 (2010)] and their generalizations have been mathematically formulated as the existence of an action of a W-algebra on the cohomology or K-theory of the instanton moduli space, together with a Whitaker vector [A. Braverman et al., e-print arXiv:1406.2381 (2014); D. Maulik and A. Okounkov, e-print arXiv:1211.1287 (2012), pp. 1-276; O. Schiffmann and E. Vasserot, Publ. Math. Inst. Hautes Etud. Sci. 118, 213-342 (2013)]. However, the original conjectures also predict intertwining properties with the natural higher rank version of the "Ext1 operator" which was previously studied by Okounkov and the author in Carlsson and Okounkov [Duke Math. J. 161, 1797-1815 (2012)], a result which is now sometimes referred to as AGT in rank one [A. Alba et al., Lett. Math. Phys. 98, 33-64 (2011); M. Pedrini et al., J. Geom. Phys. 103, 43-89 (2016)]. Physically, this corresponds to incorporating matter in the Nekrasov partition functions, an obviously important feature in the physical theory. It is therefore of interest to study how the Ext1 operator relates to the aforementioned structures on cohomology in higher rank, and if possible to find a formulation from which the AGT conjectures follow as a corollary. In this paper, we carry out something analogous using a modified Segal-Sugawara construction for the s l ˆ 2 C structure that appears in Nekrasov and Okounkov [Prog. Math. 244, 525-596 (2006)] for general rank. This immediately implies the AGT identities when the central charge is one, a case which is of particular interest for string theorists, and because of the natural appearance of the Seiberg-Witten curve in this setup, see, for instance, Dijkgraaf and Vafa [e-print arXiv:0909.2453 (2009).] as well as Iqbal et al. [J. High Energy Phys. 2009, 69].

  6. AGT101 automotive gas turbine system development

    NASA Technical Reports Server (NTRS)

    Rackley, R. A.; Kidwell, J. R.

    1982-01-01

    The AGT101 automotive gas turbine system consisting of a 74.6 kw regenerated single-shaft gas turbine engine, is presented. The development and testing of the system is reviewed, and results for aerothermodynamic components indicate that compressor and turbine performance levels are within one percent of projected levels. Ceramic turbine rotor development is encouraging with successful cold spin testing of simulated rotors to speeds over 12,043 rad/sec. Spin test results demonstrate that ceramic materials having the required strength levels can be fabricated by net shape techniques to the thick hub cross section, which verifies the feasibility of the single-stage radial rotor in single-shaft engines.

  7. The AGT 101 advanced automotive gas turbine

    NASA Technical Reports Server (NTRS)

    Rackley, R. A.; Kidwell, J. R.

    1982-01-01

    A development program is described whose goal is the accumulation of the technology base needed by the U.S. automotive industry for the production of automotive gas turbine powertrains. Such gas turbine designs must exhibit reduced fuel consumption, a multi-fuel capability, and low exhaust emissions. The AGT101 powertrain described is a 74.6 kW, regenerated single-shaft gas turbine, operating at a maximum inlet temperature of 1644 K and coupled to a split differential gearbox and automatic overdrive transmission. The engine's single stage centrifugal compressor and single stage radial inflow turbine are mounted on a common shaft, and will operate at a maximum rotor speed of 100,000 rpm. All high temperature components, including the turbine rotor, are ceramic.

  8. Advanced Gas Turbine (AGT) technology report

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Engine testing, ceramic component fabrication and evaluation, component performance rig testing, and producibility experiments at Pontiac comprised AGT 100 activities of this period, January to December 1984. Two experimental engines were available and allowed the evaluation of eight experimental assemblies. Operating time accumulated was 115 hr of burning and 156 hr total. Total cumulative engine operating time is now 225 hr. Build number 11 and 12 of engine S/N 1 totaled 28 burning hours and constituted a single assembly of the engine core--the compressor, both turbines, and the gearbox. Build number 11 of engine S/N 1 included a 1:07 hr continuous test at 100% gasifier speed (86,000 rpm). Build number 8 of engine S/N 2 was the first engine test with a ceramic turbine rotor. A mechanical loss test of an engine assembly revealed the actual losses to be near the original design allowance. Component development activity included rig testing of the compressor, combustor, and regenerator. Compressor testing was initiated on a rig modified to control the transfer of heat between flow path, lubricating oil, and structure. Results show successful thermal decoupling of the rig and lubricating/cooling oil. Rig evaluation of a reduced-friction compressor was initiated. Combustor testing covered qualification of ceramic parts for engine use, mapping of operating range limits, and evaluation of a relocated igniter plug. Several seal refinements were tested on the hot regenerator rig. An alternate regenerator disk, extruded MAS, was examined and found to be currently inadequate for the AGT 100 application. Also, a new technique for measuring leakage was explored on the regenerator rig. Ceramic component activity has focused on the development of state-of-the-art material strength characteristics in full-scale hardware. Injection-molded sintered alpha-SiC rotors were produced at Carborundum in an extensive process and tool optimization study.

  9. AGT (Advanced Gas Turbine) technology project

    NASA Technical Reports Server (NTRS)

    1988-01-01

    An overall summary documentation is provided for the Advanced Gas Turbine Technology Project conducted by the Allison Gas Turbine Division of General Motors. This advanced, high risk work was initiated in October 1979 under charter from the U.S. Congress to promote an engine for transportation that would provide an alternate to reciprocating spark ignition (SI) engines for the U.S. automotive industry and simultaneously establish the feasibility of advanced ceramic materials for hot section components to be used in an automotive gas turbine. As this program evolved, dictates of available funding, Government charter, and technical developments caused program emphases to focus on the development and demonstration of the ceramic turbine hot section and away from the development of engine and powertrain technologies and subsequent vehicular demonstrations. Program technical performance concluded in June 1987. The AGT 100 program successfully achieved project objectives with significant technology advances. Specific AGT 100 program achievements are: (1) Ceramic component feasibility for use in gas turbine engines has been demonstrated; (2) A new, 100 hp engine was designed, fabricated, and tested for 572 hour at operating temperatures to 2200 F, uncooled; (3) Statistical design methodology has been applied and correlated to experimental data acquired from over 5500 hour of rig and engine testing; (4) Ceramic component processing capability has progressed from a rudimentary level able to fabricate simple parts to a sophisticated level able to provide complex geometries such as rotors and scrolls; (5) Required improvements for monolithic and composite ceramic gas turbine components to meet automotive reliability, performance, and cost goals have been identified; (6) The combustor design demonstrated lower emissions than 1986 Federal Standards on methanol, JP-5, and diesel fuel. Thus, the potential for meeting emission standards and multifuel capability has been initiated

  10. Advanced Gas Turbine (AGT) Technology Development Project

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This report is the eleventh in the series of Technical Summary reports for the Advanced Gas Turbine (AGT) Technology Development Project, authorized under NASA Contract DEN3-167, and sponsored by the Department of Energy (DOE). This report was prepared by Garrett Turbine Engine Company, A Division of the Garrett Corporation, and includes information provided by Ford Motor Company, the Standard Oil Company, and AiResearch Casting Company. This report covers plans and progress for the period July 1, 1985 through June 30, 1986. Technical progress during the reported period was highlighted by the 85-hour endurance run of an all-ceramic engine operating in the 2000 to 2250 F temperature regime. Component development continued in the areas of the combustion/fuel injection system, regenerator and seals system, and ceramic turbine rotor attachment design. Component rig testing saw further refinements. Ceramic materials showed continued improvements in required properties for gas turbine applications; however, continued development is needed before performance and reliability goals can be set.

  11. Advanced Gas Turbine (AGT) Technology Project

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Engine testing, ceramic component fabrication and evaluation, component performance rig testing, and analytical studies comprised AGT 100 activities during the 1985 year. Ten experimental assemblies (builds) were evaluated using two engines. Accrued operating time was 120 hr of burning and 170 hr total, bringing cumulative total operating time to 395 hr, all devoid of major failures. Tests identified the generator seals as the primary working fluid leakage sources. Power transfer clutch operation was demonstrated. An alpha SiC gasifier rotor engine test resulted in blade tip failures. Recurring case vibration and shaft whip have limited gasifier shaft speeds to 84%. Ceramic components successfully engine tested now include the SiC scroll assembly, Si3N3 turbine rotor, combustor assembly, regenerator disk bulkhead, turbine vanes, piston rings, and couplings. A compressor shroud design change to reduce heat recirculation back to the inlet was executed. Ceramic components activity continues to focus on the development of state-of-the-art material strength characteristics in full-scale engine hardware. Fiber reinforced glass-ceramic composite turbine (inner) backplates were fabricated by Corning Glass Works. The BMAS/III material performed well in engine testing. Backplates of MAS material have not been engine tested.

  12. Advanced Gas Turbine (AGT) Technology Development Project, ceramic component developments

    NASA Technical Reports Server (NTRS)

    Teneyck, M. O.; Macbeth, J. W.; Sweeting, T. B.

    1987-01-01

    The ceramic component technology development activity conducted by Standard Oil Engineered Materials Company while performing as a principal subcontractor to the Garrett Auxiliary Power Division for the Advanced Gas Turbine (AGT) Technology Development Project (NASA Contract DEN3-167) is summarized. The report covers the period October 1979 through July 1987, and includes information concerning ceramic technology work categorized as common and unique. The former pertains to ceramic development applicable to two parallel AGT projects established by NASA contracts DEN3-168 (AGT100) and DEN3-167 (AGT101), whereas the unique work solely pertains to Garrett directed activity under the latter contract. The AGT101 Technology Development Project is sponsored by DOE and administered by NASA-Lewis. Standard Oil directed its efforts toward the development of ceramic materials in the silicon-carbide family. Various shape forming and fabrication methods, and nondestructive evaluation techniques were explored to produce the static structural components for the ceramic engine. This permitted engine testing to proceed without program slippage.

  13. Relationships among cell survival, O6-alkylguanine-DNA alkyltransferase activity, and reactivation of methylated adenovirus 5 and herpes simplex virus type 1 in human melanoma cell lines

    SciTech Connect

    Maynard, K.; Parsons, P.G.; Cerny, T.; Margison, G.P. )

    1989-09-01

    O6-Alkylguanine-DNA alkyltransferase (ATase) activity and host cell reactivation (HCR) of 5-(3-methyl-1-triazeno)imidazole-4-carboxamide (MTIC)-methylated viruses were compared in human melanoma cell lines that were sensitive or resistant to killing by the antitumor DNA-methylating agent MTIC. Enhanced HCR of adenovirus 5 (defined as the Mer+ phenotype) generally showed a semiquantitative correlation with the natural or induced resistance of the host cells to the toxic effects of MTIC and to the level of ATase activity. However, one MTIC-resistant cell line was found (MM170) which had a low level of ATase and intermediate HCR of adenovirus. The HCR of herpes simplex virus type 1 (HSV-1) was enhanced in the Mer+ cells that had natural resistance to MTIC compared with Mer- cells. On the other hand, HCR of HSV-1 in Mer+ cells with induced resistance to MTIC was similar to that in Mer- cells. Neither adenovirus 5 nor HSV-1 infection induced ATase activity in Mer- cells. This indicates that resistance to the toxic effects of methylating agents is not invariably associated with high levels of ATase activity in human melanoma cells. Furthermore, while induction of the Mer+ phenotype from Mer- cells was usually accompanied by the recovery of ATase activity, induced Mer+ cells had less proficient repair than natural Mer+ cells, as judged quantitatively by slightly lower cellular resistance and qualitatively by deficient HCR response for HSV-1. These results suggest that the Mer- and induced Mer+ cells lack an ATase-independent DNA repair mechanism. No differences in MTIC-induced DNA repair synthesis or strand breaks were found between the Mer-, natural Mer+, and induced Mer+ phenotypes. However, UV-induced DNA repair synthesis was higher in the natural Mer+ than in the Mer- or induced Mer+ cells, both of which had increased cellular sensitivity to the antimetabolites methotrexate and hydroxyurea.

  14. Ceramics for the AGT101 automotive gas turbine

    NASA Technical Reports Server (NTRS)

    Kreiner, D. M.; Wimmer, J. M.

    1981-01-01

    An advanced gas turbine powertrain for automotive application is being developed. Objectives of the program include a fuel consumption of 42.8 mpg on No. 2 diesel fuel in a 3000 pound car, same overall vehicle performance as obtained with a conventional spark ignition internal combustion engine, low emission, multiple fuel capacity, reliability, and competitive cost. The AGT101 powertrain consists of a power section, gearbox and transmission, and the design and analysis conducted thus far support the initial engine concept, as no significant design changes have been required. The ceramic rotor design approach and component materials are discussed, and it is projected that the AGT powertrain will be competitive with any other alternative powertrain in meeting the design objectives.

  15. Field testing advanced geothermal turbodrill (AGT). Phase 1 final report

    SciTech Connect

    Maurer, W.C.; Cohen, J.H.

    1999-06-01

    Maurer Engineering developed special high-temperature geothermal turbodrills for LANL in the 1970s to overcome motor temperature limitations. These turbodrills were used to drill the directional portions of LANL`s Hot Dry Rock Geothermal Wells at Fenton Hill, New Mexico. The Hot Dry Rock concept is to drill parallel inclined wells (35-degree inclination), hydraulically fracture between these wells, and then circulate cold water down one well and through the fractures and produce hot water out of the second well. At the time LANL drilled the Fenton Hill wells, the LANL turbodrill was the only motor in the world that would drill at the high temperatures encountered in these wells. It was difficult to operate the turbodrills continuously at low speed due to the low torque output of the LANL turbodrills. The turbodrills would stall frequently and could only be restarted by lifting the bit off bottom. This allowed the bit to rotate at very high speeds, and as a result, there was excessive wear in the bearings and on the gauge of insert roller bits due to these high rotary speeds. In 1998, Maurer Engineering developed an Advanced Geothermal Turbodrill (AGT) for the National Advanced Drilling and Excavation Technology (NADET) at MIT by adding a planetary speed reducer to the LANL turbodrill to increase its torque and reduce its rotary speed. Drilling tests were conducted with the AGT using 12 1/2-inch insert roller bits in Texas Pink Granite. The drilling tests were very successful, with the AGT drilling 94 ft/hr in Texas Pink Granite compared to 45 ft/hr with the LANL turbodrill and 42 ft/hr with a rotary drill. Field tests are currently being planned in Mexico and in geothermal wells in California to demonstrate the ability of the AGT to increase drilling rates and reduce drilling costs.

  16. DNA Repair by Reversal of DNA Damage

    PubMed Central

    Yi, Chengqi; He, Chuan

    2013-01-01

    Endogenous and exogenous factors constantly challenge cellular DNA, generating cytotoxic and/or mutagenic DNA adducts. As a result, organisms have evolved different mechanisms to defend against the deleterious effects of DNA damage. Among these diverse repair pathways, direct DNA-repair systems provide cells with simple yet efficient solutions to reverse covalent DNA adducts. In this review, we focus on recent advances in the field of direct DNA repair, namely, photolyase-, alkyltransferase-, and dioxygenase-mediated repair processes. We present specific examples to describe new findings of known enzymes and appealing discoveries of new proteins. At the end of this article, we also briefly discuss the influence of direct DNA repair on other fields of biology and its implication on the discovery of new biology. PMID:23284047

  17. Advanced Gas Turbine (AGT) powertrain system development for automotive applications

    NASA Technical Reports Server (NTRS)

    1982-01-01

    A gas turbine powertrain for automobiles with reduced fuel consumption and reduced environmental impact is investigated. The automotive gas turbine, when installed in an automobile (3000 pounds inertia weight), provides a CFDC fuel economy of 42.8 miles per gallon based on EPA test procedures and diesel No. 2 fuel. The AGT powered vehicle substantially gives the same overall vehicle driveability and performance as a comparable production vehicle powered by a conventional spark ignition powertrain system. The emissions are less than federal standards, and a variety of fuels can be used.

  18. Advanced Gas Turbine (AGT) Technology Development Project annual report

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This report is the tenth in a series of Technical Summary reports for the Advanced Gas Turbine (AGT) Technology Development Project, authorized under NASA Contract DEN3-167, and sponsored by the Department of Energy (DOE). This report was prepared by Garrett Turbine Engine Company, A Division of the Garrett Corporation, and includes information provided by Ford Motor Company, the Carborundum Company, and AiResearch Casting Company. The Project is administered by Mr. Thomas N. Strom, Project Manager, NASA-Lewis Research Center, Cleveland, Ohio. This report covers plans and progress for the period July 1, 1984 through June 30, 1985.

  19. AGT relations for abelian quiver gauge theories on ALE spaces

    NASA Astrophysics Data System (ADS)

    Pedrini, Mattia; Sala, Francesco; Szabo, Richard J.

    2016-05-01

    We construct level one dominant representations of the affine Kac-Moody algebra gl̂k on the equivariant cohomology groups of moduli spaces of rank one framed sheaves on the orbifold compactification of the minimal resolution Xk of the Ak-1 toric singularity C2 /Zk. We show that the direct sum of the fundamental classes of these moduli spaces is a Whittaker vector for gl̂k, which proves the AGT correspondence for pure N = 2 U(1) gauge theory on Xk. We consider Carlsson-Okounkov type Ext-bundles over products of the moduli spaces and use their Euler classes to define vertex operators. Under the decomposition gl̂k ≃ h ⊕sl̂k, these vertex operators decompose as products of bosonic exponentials associated to the Heisenberg algebra h and primary fields of sl̂k. We use these operators to prove the AGT correspondence for N = 2 superconformal abelian quiver gauge theories on Xk.

  20. Advanced Gas Turbine (AGT) powertrain system development for automotive applications

    NASA Technical Reports Server (NTRS)

    1981-01-01

    An automotive gas turbine powertrain system which, when installed in a 1985 production vehicle (3000 pounds inertia weight), is being developed with a CFDC fuel economy of 42.8 miles per gallon based on Environmental Protection Agency (EPA) test procedures and diesel No. 2 fuel. The AGT-powered vehicle shall give substantially the same overall vehicle driveability and performance as a comparable 1985 production vehicle powered by a conventional spark ignition powertrain system (baseline system). Gaseous emissions and particulate levels less than: NOx = 0.4 gm/mile, HC = 0.41 gm/mile, and CO = 3.4 gm/mile, and a total particulate of 0.2 gm/mile, using the same fuel as used for fuel economy measurements is expected, along with the ability to use a variety of alternate fuels.

  1. Advanced Gas Turbine (AGT) powertrain system development for automotive applications

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Progress in the development of a gas turbine engine to improve fuel economy, reduce gaseous emissions and particulate levels, and compatible with a variety of alternate fuels is reported. The powertrain is designated AGT101 and consists of a regenerated single shaft gas turbine engine, a split differential gearbox and a Ford Automatic Overdrive production transmission. The powertrain is controlled by an electronic digital microprocessor and associated actuators, instrumentation, and sensors. Standard automotive accessories are driven by engine power provided by an accessory pad on the gearbox. Component/subsystem development progress is reported in the following areas: compressor, turbine, combustion system, regenerator, gearbox/transmission, structures, ceramic components, foil gas bearing, bearings and seals, rotor dynamics, and controls and accessories.

  2. Generalized Rogers Ramanujan Identities Motivated by AGT Correspondence

    NASA Astrophysics Data System (ADS)

    Belavin, Alexander A.; Gepner, Doron R.

    2013-12-01

    AGT correspondence and its generalizations attracted a great deal of attention recently. In particular, it was suggested that U( r) instantons on describe the conformal blocks of the coset , where n is a parameter. It has been shown that the representations of algebra A( r, p) n for generic values n possesses the distinguished geometrical bases. It is interesting to consider the case when the parameter n is integer. We will concentrate on this case and describe Generalized Rogers Ramanujan (GRR) identities for these cosets, which expresses the characters as certain q series. We propose that such identities exist for the coset A( r, p) n for all positive integers n and all r and p. We treat here the case of n = 1 and r = 2, finding GRR identities for all the characters.

  3. A technology development summary for the AGT101 advanced gas turbine program

    NASA Technical Reports Server (NTRS)

    Boyd, Gary L.; Kidwell, James R.; Kreiner, Daniel M.

    1987-01-01

    A summary is presented of significant technology developments that have been made in the AGT101 advanced gas turbine program. The AGT101 design features are reviewed, and the power section testing and results are addressed in detail. The results of component testing and evaluation are described for the compressor, turbine, regenerator, and foil bearing. Ceramic component development is discussed, including that of the static seal, turbine shroud seal, regenerator shield planar seal, regenerator shield piston ring, stator rig, ceramic combustor, and turbine rotor. Important areas to be addressed by the Advanced Turbine Technology Applications Project now in the planning stage at DOE and NASA are briefly reviewed.

  4. Effects of microRNA-29a on retinopathy of prematurity by targeting AGT in a mouse model

    PubMed Central

    Chen, Xin-Ke; Ouyang, Li-Juan; Yin, Zheng-Qin; Xia, Yuan-You; Chen, Xiu-Rong; Shi, Hui; Xiong, Yan; Pi, Lian-Hong

    2017-01-01

    Background: This study aimed to explore the effects of microRNA-29a (miR-29a) on retinopathy of prematurity (ROP) by targeting angiotensinogen (AGT) expression in a mouse model. Methods: Ninety-six C57BL/6J mice were selected and divided into the normal control group (n = 12) and the oxygen-induced retinopathy (OIR) group (n = 84). All the mice in the OIR group were assigned to the following seven groups (12 mice in each group): the blank, miR-29a mimics, miR-29a inhibitors, empty plasmid, miR-29a mimics + si-AGT, miR-29a inhibitors + si-AGT and si-AGT groups. ADPase histochemical staining was conducted to detect the morphology of retinal neovascularization. H&E staining was performed to quantify retinal neovascularization. The qRT-PCR assay was applied to detect the expression levels of miR-29a and the AGT mRNA. Western blotting was used to detect the protein expressions of AGT, vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), angiotensin (ANG) and angiotensin II (AngII). Results: Compared with the normal control group, miR-29a expression decreased, while the AGT mRNA expression and the protein expression levels of AGT, VEGF, HGF, ANG and AngII increased, and retinal vascular density and neovascularization also increased in the OIR group. In the OIR group, compared with the blank, empty plasmid, miR-29a inhibitors and miR-29a inhibitors + si-AGT groups, miR-29a expression increased, while the AGT mRNA expression and protein expression levels of AGT, VEGF, HGF, ANG and AngII decreased, and retinal vascular density and neovascularization also decreased in the miR-29a mimics, miR-29a mimics + si-AGT and si-AGT groups. Conclusion: MiR-29a could inhibit retinal neovascularization to prevent the development and progression of ROP by down-regulating AGT. PMID:28337307

  5. Esophageal carcinogenesis in the rat: zinc deficiency, DNA methylation and alkyltransferase activity.

    PubMed

    Newberne, P M; Broitman, S; Schrager, T F

    1997-01-01

    Rats fed zinc-deficient diets and given an esophageal carcinogen, methylbenzylnitrosamine, develop tumors in greater incidence and with increased frequency compared to zinc-supplemented rats. This greater susceptibility is associated with a unique esophageal lesion, parakeratosis, with markedly increased epithelial necrosis and cell proliferation. Recent studies have shown that the increased susceptibility to tumorigenesis was further associated with a number of metabolic and biochemical alterations including increased binding of the carcinogen to DNA, shifts in O6-methylguanine (O6MeG)/7-methylguanine ratios and suggestions that the promutagen O6MeG lesion is not repaired effectively in the zinc-deficient esophagus; the latter was not reflected in the amount of O6-methyltransferase activity, however. The weight of evidence supports a presumption that zinc deficiency interferes with normal DNA repair mechanisms, the nature of which is not clear. An interesting additional finding was that zinc deficiency alone was associated with esophageal tumor induction, without carcinogen, which indicates that genetic material in the zinc-deficient esophageal epithelium is damaged sufficiently, without further chemical injury, to result in loss of control of cell proliferation. Manipulation of the time of exposure to zinc deficiency and carcinogen exposure defined the initiation period as most affected by the deficiency. Furthermore, reduced carcinogen exposure (and less toxicity), along with zinc deficiency, permits development of more tumors of the endophytic type, the form more relevant to human esophageal tumors. The groundwork, as described in this paper, has now been prepared to directly address the latter issue, endophytic tumors, and the putative relation of zinc deficiency to esophageal cancer in human populations.

  6. Three Agt1 transporters from brewer's yeasts exhibit different temperature dependencies for maltose transport over the range of brewery temperatures (0–20 °C).

    PubMed

    Vidgren, Virve; Viljanen, Kaarina; Mattinen, Laura; Rautio, Jari; Londesborough, John

    2014-06-01

    Zero-trans rates of maltose transport by brewer's yeasts exert strong control over fermentation rates and are strongly temperature-dependent over the temperature range (20–0 °C) of brewery fermentations. Three α-glucoside transporters, ScAgt1(A60) (a Saccharomyces cerevisiae version of Agt1 from an ale strain), ScAgt1-A548V (a variant of ScAgt1(A60) with a single amino acid change in a transmembrane domain), and SbAgt1 (a Saccharomyces (eu)bayanus version from a lager strain), were compared. When expressed in the same laboratory yeast, grown at 24 °C and assayed at 0, 10, and 20 °C, SbAgt1 had the lowest absolute maltose uptake activity at 20 °C but smallest temperature dependence, ScAgt1-A548V had the highest activity but greatest temperature dependence, and ScAgt1(A60) had intermediate properties. ScAgt1(A60) exhibited higher absolute rates and smaller temperature dependencies when expressed in laboratory rather than brewer's strains. Absolute rates closely reflected the amounts of GFP-tagged ScAgt1(A60) transporter in each host's plasma membrane. Growth at 15 °C instead of 24 °C decreased the absolute activities of strains expressing ScAgt1(A60) by two- to threefold. Evidently, the kinetic characteristics of at least ScAgt1(A60) depended on the nature of the host plasma membrane. However, no consistent correlation was observed between transport activities and fatty acid or ergosterol compositions.

  7. A polymorphism in AGT and AGTR1 gene is associated with lead-related high blood pressure.

    PubMed

    Kim, Hyung-Ki; Lee, Hwayoung; Kwon, Jun-Tack; Kim, Hak-Jae

    2015-12-01

    We investigated the association of polymorphisms in two renin-angiotensin system-related genes, expressed as angiotensinogen (AGT) and angiotensin II type 1 receptor (AGTR1), with blood lead levels and lead-related blood pressure in lead-exposed male workers in Korea. A cross-sectional study involving 808 lead-exposed male workers in Korea was conducted using a restriction fragment length polymorphism-based strategy to differentiate the various genotypes of polymorphisms in the AGT and AGTR1 genes. The association of clinical characteristics with genotypes as modifiers was estimated after adjustment for age, smoking status, drinking status, body mass index and job duration of each subject. Genotype and allele frequencies of the M235T polymorphism in AGT were associated with lead-related high blood pressure status. Moreover, blood lead levels were associated with allele frequencies of the AGT M235T polymorphism. These results suggested that the M/M genotype and M allele of AGT are risk factors for lead-related high blood pressure.

  8. Ionizing radiation induces O6-alkylguanine-DNA-alkyltransferase mRNA and activity in mouse tissues.

    PubMed

    Wilson, R E; Hoey, B; Margison, G P

    1993-04-01

    The effect of exposure to whole-body gamma-irradiation or fast electrons on O6-alkylguanine-DNA-alkyltransferase (ATase) activity and mRNA abundance has been examined in mice. In response to gamma-radiation, hepatic ATase activity was significantly raised in BDF1 mice 24 h post-irradiation, reaching a maximum of 2- to 3-fold at 36 h and beginning to decrease by 48-60 h. A small but consistently higher level of induction was achieved when mice were exposed using a low dose rate (0.015 Gy/min) compared to a high dose rate (0.5 Gy/min). ATase activity was also induced approximately 2-fold 48 h post-irradiation in brain, kidney, lung and spleen, with a greater induction again observed in response to the lower dose rate. In response to fast electrons from a linear accelerator hepatic ATase activity was also induced 2- to 3-fold 48 h post-irradiation in BDF1, BALB/c, C57Bl and DBA2 strains. Induction of ATase activity in livers of BDF1 mice was observed 48 h after a total single dose of 5 Gy gamma-radiation (2-fold), increasing to a slightly higher level at 15 Gy, but no induction was observed at doses of 2 Gy and below. Although a maximum 2- to 3-fold induction of ATase activity was observed, mRNA levels were induced 3- to 4-fold by 48 h after a dose of 15 Gy. Furthermore, significant increases in mRNA levels were detected at low doses (1-2 Gy) at which there was no apparent increase in ATase activity. This suggests that ionizing radiation increases ATase levels by a process involving transcriptional upregulation but that strong post-transcriptional and/or translational controls operate to limit induction of enzyme activity to 2- to 3-fold. This is the first report of an in vivo induction of ATase by ionizing radiation in a species other than the rat.

  9. Advanced Gas Turbine (AGT) powertrain system development for automotive applications report

    NASA Technical Reports Server (NTRS)

    1984-01-01

    This report describes progress and work performed during January through June 1984 to develop technology for an Advanced Gas Turbine (AGT) engine for automotive applications. Work performed during the first eight periods initiated design and analysis, ceramic development, component testing, and test bed evaluation. Project effort conducted under this contract is part of the DOE Gas Turbine Highway Vehicle System Program. This program is oriented at providing the United States automotive industry the high-risk long-range techology necessary to produce gas turbine engines for automobiles with reduced fuel consumption and reduced environmental impact. Technology resulting from this program is intended to reach the marketplace by the early 1990s.

  10. A novel thermostable protein-tag: optimization of the Sulfolobus solfataricus DNA- alkyl-transferase by protein engineering.

    PubMed

    Vettone, Antonella; Serpe, Mario; Hidalgo, Aurelio; Berenguer, José; del Monaco, Giovanni; Valenti, Anna; Rossi, Mosé; Ciaramella, Maria; Perugino, Giuseppe

    2016-01-01

    In the last decade, a powerful biotechnological tool for the in vivo and in vitro specific labeling of proteins (SNAP-tag™ technology) was proposed as a valid alternative to classical protein-tags (green fluorescent proteins, GFPs). This was made possible by the discovery of the irreversible reaction of the human alkylguanine-DNA-alkyl-transferase (hAGT) in the presence of benzyl-guanine derivatives. However, the mild reaction conditions and the general instability of the mesophilic SNAP-tag™ make this new approach not fully applicable to (hyper-)thermophilic and, in general, extremophilic organisms. Here, we introduce an engineered variant of the thermostable alkylguanine-DNA-alkyl-transferase from the Archaea Sulfolobus solfataricus (SsOGT-H5), which displays a catalytic efficiency comparable to the SNAP-tag™ protein, but showing high intrinsic stability typical of proteins from this organism. The successful heterologous expression obtained in a thermophilic model organism makes SsOGT-H5 a valid candidate as protein-tag for organisms living in extreme environments.

  11. Role of ACE and AGT gene polymorphisms in genetic susceptibility to diabetes mellitus type 2 in a Brazilian sample.

    PubMed

    Wollinger, L M; Dal Bosco, S M; Rempe, C; Almeida, S E M; Berlese, D B; Castoldi, R P; Arndt, M E; Contini, V; Genro, J P

    2015-12-29

    The aim of the current study was to investigate the association between the InDel polymorphism in the angiotensin I-converting enzyme gene (ACE) and the rs699 polymorphism in the angiotensinogen gene (AGT) and diabetes mellitus type 2 (DM2) in a sample population from Southern Brazil. A case-control study was conducted with 228 patients with DM2 and 183 controls without DM2. The ACE InDel polymorphism was genotyped by polymerase chain reaction (PCR) with specific primers, followed by electrophoresis on 1.5% agarose gel. The AGT rs699 polymorphism was genotyped using a real-time PCR assay. No significant association between the ACE InDel polymorphism and DM2 was detected (P = 0.97). However, regarding the AGT rs699 polymorphism, DM2 patients had a significantly higher frequency of the AG genotype and lower frequency of the GG genotype when compared to the controls (P = 0.03). Our results suggest that there is an association between the AGT rs699 polymorphism and DM2 in a Brazilian sample.

  12. ATTAP/AGT101 - Year 2 progress in ceramic technology development

    NASA Technical Reports Server (NTRS)

    Kidwell, J. R.; Lindberg, L. J.; Morey, R. E.

    1990-01-01

    The progress made by the Advanced Turbine Technology Applications Project (ATTAP) is summarized, with emphasis on the following areas: ceramic materials assessment and characterization, ceramic impact damage assessment, ceramic combustor evaluation, turbine inlet particle separator development, impact-tolerant turbine designs, and net-shape ceramic component fabrications. In the evolutionary ceramics development in the Automotive Gas Turbine (AGT101) and ATTAP programs initial designs were conceived to reduce stresses by using well-established criteria: bodies of revolution were preferred over nonaxisymmetric geometries, sharp corners were avoided, the contact area between components was kept as large as possible, and small parts were preferred over large when feasible. Projects discussed include: initial ceramic component fabrication by ceramic suppliers in 1990, engine test to 1371 C in 1991, 100-hr test bed engine durability test in 1991, and 300-hr test bed engine durability in 1992.

  13. Meningocele repair

    MedlinePlus

    ... Myelodysplasia repair; Spinal dysraphism repair; Meningomyelocele repair; Neural tube defect repair; Spina bifida repair ... If your child has hydrocephalus, a shunt (plastic tube) will be put in the child's brain to ...

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

    PubMed Central

    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 O6-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. PMID:21234336

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

    DOE PAGES

    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

  16. The AGT Gene M235T Polymorphism and Response of Power-Related Variables to Aerobic Training

    PubMed Central

    Aleksandra, Zarębska; Zbigniew, Jastrzębski; Waldemar, Moska; Agata, Leońska-Duniec; Mariusz, Kaczmarczyk; Marek, Sawczuk; Agnieszka, Maciejewska-Skrendo; Piotr, Żmijewski; Krzysztof, Ficek; Grzegorz, Trybek; Ewelina, Lulińska-Kuklik; Semenova, Ekaterina A.; Ahmetov, Ildus I.; Paweł, Cięszczyk

    2016-01-01

    The C allele of the M235T (rs699) polymorphism of the AGT gene correlates with higher levels of angiotensin II and has been associated with power and strength sport performance. The aim of the study was to investigate whether or not selected power-related variables and their response to a 12-week program of aerobic dance training are modulated by the AGT M235T genotype in healthy participants. Two hundred and one Polish Caucasian women aged 21 ± 1 years met the inclusion criteria and were included in the study. All women completed a 12-week program of low and high impact aerobics. Wingate peak power and total work capacity, 5 m, 10 m, and 30 m running times and jump height and jump power were determined before and after the training programme. All power-related variables improved significantly in response to aerobic dance training. We found a significant association between the M235T polymorphism and jump-based variables (squat jump (SJ) height, p = 0.005; SJ power, p = 0.015; countermovement jump height, p = 0.025; average of 10 countermovement jumps with arm swing (ACMJ) height, p = 0.001; ACMJ power, p = 0.035). Specifically, greater improvements were observed in the C allele carriers in comparison with TT homozygotes. In conclusion, aerobic dance, one of the most commonly practiced adult fitness activities in the world, provides sufficient training stimuli for augmenting the explosive strength necessary to increase vertical jump performance. The AGT gene M235T polymorphism seems to be not only a candidate gene variant for power/strength related phenotypes, but also a genetic marker for predicting response to training. Key points Aerobic dance provides sufficient training stimuli for the improvement of explosive power. The AGT gene M235T polymorphism is associated with individual variation in the change of power-related phenotypes in response to aerobic dance training. The C allele carriers of the AGT gene M235T polymorphism show greater improvements of jump

  17. Novel regulation of Skp1 by the Dictyostelium AgtA α-galactosyltransferase involves the Skp1-binding activity of its WD40 repeat domain.

    PubMed

    Schafer, Christopher M; Sheikh, M Osman; Zhang, Dongmei; West, Christopher M

    2014-03-28

    The role of Skp1 as an adaptor protein that links Cullin-1 to F-box proteins in E3 Skp1/Cullin-1/F-box protein (SCF) ubiquitin ligases is well characterized. In the social amoeba Dictyostelium and probably many other unicellular eukaryotes, Skp1 is modified by a pentasaccharide attached to a hydroxyproline near its C terminus. This modification is important for oxygen-sensing during Dictyostelium development and is mediated by a HIF-α type prolyl 4-hydroxylase and five sequentially acting cytoplasmic glycosyltransferase activities. Gene disruption studies show that AgtA, the enzyme responsible for addition of the final two galactose residues, in α-linkages to the Skp1 core trisaccharide, is unexpectedly critical for oxygen-dependent terminal development. AgtA possesses a WD40 repeat domain C-terminal to its single catalytic domain and, by use of domain deletions, binding studies, and enzyme assays, we find that the WD40 repeats confer a salt-sensitive second-site binding interaction with Skp1 that mediates novel catalytic activation in addition to simple substrate recognition. In addition, AgtA binds similarly well to precursor isoforms of Skp1 by a salt-sensitive mechanism that competes with binding to an F-box protein and recognition by early modification enzymes, and the effect of binding is diminished when AgtA modifies Skp1. Genetic studies show that loss of AgtA is more severe when an earlier glycosylation step is blocked, and overexpressed AgtA is deleterious if catalytically inactivated. Together, the findings suggest that AgtA mediates non-enzymatic control of unmodified and substrate precursor forms of Skp1 by a binding mechanism that is normally relieved by switch-like activation of its glycosylation function.

  18. Combinatorial Study of Ag-Te Thin Films and Their Application as Cation Supply Layer in CBRAM Cells.

    PubMed

    Devulder, Wouter; Opsomer, Karl; Meersschaut, Johan; Deduytsche, Davy; Jurczak, Malgorzata; Goux, Ludovic; Detavernier, Christophe

    2015-05-11

    In this work, we investigate binary Ag-Te thin films and their functionality as a cation supply layer in conductive bridge random access memory devices. A combinatorial sputter deposition technique is used to deposit a graded Ag(x)Te(1-x) (0 < x < 1) layer with varying composition as a function of the position on the substrate. The crystallinity, surface morphology, and material stability under thermal treatment as a function of the composition of the material are investigated. From this screening, a narrow composition range between 33 and 38 at% Te is selected which shows a good morphology and a high melting temperature. Functionality of a single Ag(2-δ)Te composition as cation supply layer in CBRAM with dedicated Al2O3 switching layer is then investigated by implementing it in 580 μm diameter dot Pt/Ag(2-δ)Te/Al2O3/Si cells. Switching properties are investigated and compared to cells with a pure Ag cation supply layer. An improved cycling behavior is observed when Te is added compared to pure Ag, which we relate to the ionic conducting properties of Ag2Te and the preferred formation of Ag-Te phases.

  19. AgtA, the Dicarboxylic Amino Acid Transporter of Aspergillus nidulans, Is Concertedly Down-Regulated by Exquisite Sensitivity to Nitrogen Metabolite Repression and Ammonium-Elicited Endocytosis▿ †

    PubMed Central

    Apostolaki, Angeliki; Erpapazoglou, Zoi; Harispe, Laura; Billini, Maria; Kafasla, Panagiota; Kizis, Dimosthenis; Peñalva, Miguel Angel; Scazzocchio, Claudio; Sophianopoulou, Vicky

    2009-01-01

    We identified agtA, a gene that encodes the specific dicarboxylic amino acid transporter of Aspergillus nidulans. The deletion of the gene resulted in loss of utilization of aspartate as a nitrogen source and of aspartate uptake, while not completely abolishing glutamate utilization. Kinetic constants showed that AgtA is a high-affinity dicarboxylic amino acid transporter and are in agreement with those determined for a cognate transporter activity identified previously. The gene is extremely sensitive to nitrogen metabolite repression, depends on AreA for its expression, and is seemingly independent from specific induction. We showed that the localization of AgtA in the plasma membrane necessitates the ShrA protein and that an active process elicited by ammonium results in internalization and targeting of AgtA to the vacuole, followed by degradation. Thus, nitrogen metabolite repression and ammonium-promoted vacuolar degradation act in concert to downregulate dicarboxylic amino acid transport activity. PMID:19168757

  20. Eardrum repair

    MedlinePlus

    ... Ossicular fixation - surgery Images Eardrum repair - series References Adams ME, El-Kashlan HK. Tympanoplasty and ossiculoplasty. In: ... commercial use must be authorized in writing by ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer ...

  1. Hydrocele repair

    MedlinePlus

    ... is excellent. However, another hydrocele may form over time, or if there was also a hernia present. Alternative Names Hydrocelectomy Images Hydrocele repair - series References Aiken JJ, Oldham KT. Inguinal hernias. In: ...

  2. Tissue repair

    PubMed Central

    2010-01-01

    As living beings that encounter every kind of traumatic event from paper cut to myocardial infarction, we must possess ways to heal damaged tissues. While some animals are able to regrow complete body parts following injury (such as the earthworm who grows a new head following bisection), humans are sadly incapable of such feats. Our means of recovery following tissue damage consists largely of repair rather than pure regeneration. Thousands of times in our lives, a meticulously scripted but unseen wound healing drama plays, with cells serving as actors, extracellular matrix as the setting and growth factors as the means of communication. This article briefly reviews the cells involved in tissue repair, their signaling and proliferation mechanisms and the function of the extracellular matrix, then presents the actors and script for the three acts of the tissue repair drama. PMID:21220961

  3. Advanced Gas Turbine (AGT)

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The development and progress of the Advanced Gas Turbine engine program is examined. An analysis of the role of ceramics in the design and major engine components is included. Projected fuel economy, emissions and performance standards, and versatility in fuel use are also discussed.

  4. Advanced GPS Technologies (AGT)

    DTIC Science & Technology

    2015-05-01

    AND ADDRESS(ES) Air Force Research Laboratory,Space Vehicles Directorate,3550 Aberdeen Avenue SE , Kirtland AFB,NM,87117 8. PERFORMING ORGANIZATION...Inform Partnership Council about AFRL technology investments to improve affordability and performance of the GPS Space Segment Summary • Working in...development Exploring/opening paths to the future! Distribution A 2 \\.J ••• • AFRL Investments Supporting GPS Space Segment • AFRL is investigating

  5. Motorcycle Repair.

    ERIC Educational Resources Information Center

    Hein, Jim; Bundy, Mike

    This motorcycle repair curriculum guide contains the following ten areas of study: brake systems, clutches, constant mesh transmissions, final drives, suspension, mechanical starting mechanisms, electrical systems, fuel systems, lubrication systems, and overhead camshafts. Each area consists of one or more units of instruction. Each instructional…

  6. Snowmobile Repair.

    ERIC Educational Resources Information Center

    Helbling, Wayne

    This guide is designed to provide and/or improve instruction for occupational training in the area of snowmobile repair, and includes eight areas. Each area consists of one or more units of instruction, with each instructional unit including some or all of the following basic components: Performance objectives, suggested activities for teacher and…

  7. Outboard Repair.

    ERIC Educational Resources Information Center

    Hardway, Jack

    This consortium-developed instructor's manual for small engine repair (with focus on outboard motors) consists of the following nine instructional units: electrical remote control assembly, mechanical remote control assembly, tilt assemblies, exhaust housing, propeller and trim tabs, cooling system, mechanical gearcase, electrical gearcase, and…

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

    DOEpatents

    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.

  9. Molecular characterization of an adaptive response to alkylating agents in the opportunistic pathogen Aspergillus fumigatus

    PubMed Central

    O’Hanlon, Karen A.; Margison, Geoffrey P.; Hatch, Amy; Fitzpatrick, David A.; Owens, Rebecca A.; Doyle, Sean; Jones, Gary W.

    2012-01-01

    An adaptive response to alkylating agents based upon the conformational change of a methylphosphotriester (MPT) DNA repair protein to a transcriptional activator has been demonstrated in a number of bacterial species, but this mechanism appears largely absent from eukaryotes. Here, we demonstrate that the human pathogen Aspergillus fumigatus elicits an adaptive response to sub-lethal doses of the mono-functional alkylating agent N-methyl-N′-nitro-N-nitrosoguanidine (MNNG). We have identified genes that encode MPT and O6-alkylguanine DNA alkyltransferase (AGT) DNA repair proteins; deletions of either of these genes abolish the adaptive response and sensitize the organism to MNNG. In vitro DNA repair assays confirm the ability of MPT and AGT to repair methylphosphotriester and O6-methylguanine lesions respectively. In eukaryotes, the MPT protein is confined to a select group of fungal species, some of which are major mammalian and plant pathogens. The evolutionary origin of the adaptive response is bacterial and rooted within the Firmicutes phylum. Inter-kingdom horizontal gene transfer between Firmicutes and Ascomycete ancestors introduced the adaptive response into the Fungal kingdom. Our data constitute the first detailed characterization of the molecular mechanism of the adaptive response in a lower eukaryote and has applications for development of novel fungal therapeutics targeting this DNA repair system. PMID:22669901

  10. Engineering the elongation factor Tu for efficient selenoprotein synthesis.

    PubMed

    Haruna, Ken-ichi; Alkazemi, Muhammad H; Liu, Yuchen; Söll, Dieter; Englert, Markus

    2014-09-01

    Selenocysteine (Sec) is naturally co-translationally incorporated into proteins by recoding the UGA opal codon with a specialized elongation factor (SelB in bacteria) and an RNA structural signal (SECIS element). We have recently developed a SECIS-free selenoprotein synthesis system that site-specifically--using the UAG amber codon--inserts Sec depending on the elongation factor Tu (EF-Tu). Here, we describe the engineering of EF-Tu for improved selenoprotein synthesis. A Sec-specific selection system was established by expression of human protein O(6)-alkylguanine-DNA alkyltransferase (hAGT), in which the active site cysteine codon has been replaced by the UAG amber codon. The formed hAGT selenoprotein repairs the DNA damage caused by the methylating agent N-methyl-N'-nitro-N-nitrosoguanidine, and thereby enables Escherichia coli to grow in the presence of this mutagen. An EF-Tu library was created in which codons specifying the amino acid binding pocket were randomized. Selection was carried out for enhanced Sec incorporation into hAGT; the resulting EF-Tu variants contained highly conserved amino acid changes within members of the library. The improved UTu-system with EF-Sel1 raises the efficiency of UAG-specific Sec incorporation to >90%, and also doubles the yield of selenoprotein production.

  11. Brain aneurysm repair

    MedlinePlus

    ... aneurysm repair; Dissecting aneurysm repair; Endovascular aneurysm repair - brain; Subarachnoid hemorrhage - aneurysm ... Your scalp, skull, and the coverings of the brain are opened. A metal clip is placed at ...

  12. Eye muscle repair - discharge

    MedlinePlus

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  13. INTERNAL REPAIR OF PIPELINES

    SciTech Connect

    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.

  14. Mismatch repair.

    PubMed

    Fishel, Richard

    2015-10-30

    Highly conserved MutS homologs (MSH) and MutL homologs (MLH/PMS) are the fundamental components of mismatch repair (MMR). After decades of debate, it appears clear that the MSH proteins initiate MMR by recognizing a mismatch and forming multiple extremely stable ATP-bound sliding clamps that diffuse without hydrolysis along the adjacent DNA. The function(s) of MLH/PMS proteins is less clear, although they too bind ATP and are targeted to MMR by MSH sliding clamps. Structural analysis combined with recent real-time single molecule and cellular imaging technologies are providing new and detailed insight into the thermal-driven motions that animate the complete MMR mechanism.

  15. Book Repair Manual.

    ERIC Educational Resources Information Center

    Milevski, Robert J.

    1995-01-01

    This book repair manual developed for the Illinois Cooperative Conservation Program includes book structure and book problems, book repair procedures for 4 specific problems, a description of adhesive bindings, a glossary, an annotated list of 11 additional readings, book repair supplies and suppliers, and specifications for book repair kits. (LRW)

  16. Analysis of Polymorphisms in Genes (AGT, MTHFR, GPIIIa, and GSTP1) Associated with Hypertension, Thrombophilia and Oxidative Stress in Mestizo and Amerindian Populations of México

    PubMed Central

    Juárez-Velázquez, Rocio; Canto, Patricia; Canto-Cetina, Thelma; Rangel-Villalobos, Hector; Rosas-Vargas, Haydee; Rodríguez, Maricela; Canizales-Quinteros, Samuel; Velázquez Wong, Ana Claudia; Ordoñez-Razo, Rosa María; Vilchis-Dorantes, Guadalupe; Coral-Vázquez, Ramón Mauricio

    2010-01-01

    Several polymorphisms related to hypertension, thrombophilia, and oxidative stress has been associated with the development of cardiovascular disease. We analyzed the frequency of M235T angiotensinogen (AGT), A222V 5,10 methylenete-trahydrofolate reductase (MTHFR), L33P glycoprotein IIIa (GPIIIa), and I105V glutathione S-transferase P1 (GSTP1) polymorphisms in 285 individuals belonging to Mexican-Mestizo and five Amerindian population from México, by real time PCR allelic discrimination. Allele and genotype frequencies were compared using χ2 tests. All populations followed the Hardy Weinberg equilibrium for assay markers with the exception of the Triki, whose were in Hardy Weinberg dysequilibrium for the glutathione S-transferase P1 polymorphism. Interestingly, according to all the analyzed single nucleotide polymorphisms (SNPs), the Triki population was the most differentiated and homogeneous group of the six populations analyzed. A comparison of our data with those previously published for some Caucasian, Asian and Black populations showed quite significant differences. These differences were remarkable with all the Mexican populations having a lower frequency of the 105V allele of the glutathione S-transferase P1 and reduced occurrence of the 222A allele of the 5,10 methylenetetrahydrofolate reductase. Our results show the genetic diversity among different Mexican populations and with other racial groups. PMID:20592457

  17. Rapid road repair vehicle

    DOEpatents

    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.

  18. Rapid road repair vehicle

    DOEpatents

    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.

  19. Inguinal hernia repair

    MedlinePlus

    ... This repair can be done with open or laparoscopic surgery. You and your surgeon can discuss which type ... the repair, the cuts are stitched closed. In laparoscopic surgery: The surgeon makes three to five small cuts ...

  20. Laparoscopic Inguinal Hernia Repair

    MedlinePlus

    ... Some hernia repairs are performed using a small telescope known as a laparoscope. If your surgeon has ... in the abdominal wall (muscle) using small incisions, telescopes and a patch (mesh). Laparoscopic repair offers a ...

  1. Collision Repair Campaign

    EPA Pesticide Factsheets

    The Collision Repair Campaign targets meaningful risk reduction in the Collision Repair source category to reduce air toxic emissions in their communities. The Campaign also helps shops to work towards early compliance with the Auto Body Rule.

  2. Retinal detachment repair

    MedlinePlus

    Scleral buckling; Vitrectomy; Pneumatic retinopexy; Laser retinopexy; Rhegmatogenous retinal detachment repair ... it meets the hole in the retina. Scleral buckling can be done using numbing medicine while you ...

  3. Exts and the AGT Relations

    NASA Astrophysics Data System (ADS)

    Neguţ, Andrei

    2016-09-01

    We prove the connection between the Nekrasov partition function of {N=2} super-symmetric U(2) gauge theory with adjoint matter and conformal blocks for the Virasoro algebra, as predicted by the Alday-Gaiotto-Tachikawa relations. Mathematically, this is achieved by relating the Carlsson-Okounkov Ext vector bundle on the moduli space of rank 2 sheaves with Liouville vertex operators. Our approach is geometric in nature, and uses a new method for intersection-theoretic computations of the Ext operator.

  4. AGT-102 automotive gas turbine

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Development of a gas turbine powertrain with a 30% fuel economy improvement over a comparable S1 reciprocating engine, operation within 0.41 HC, 3.4 CO, and 0.40 NOx grams per mile emissions levels, and ability to use a variety of alternate fuels is summarized. The powertrain concept consists of a single-shaft engine with a ceramic inner shell for containment of hot gasses and support of twin regenerators. It uses a fixed-geometry, lean, premixed, prevaporized combustor, and a ceramic radial turbine rotor supported by an air-lubricated journal bearing. The engine is coupled to the vehicle through a widerange continuously variable transmission, which utilizes gearing and a variable-ratio metal compression belt. A response assist flywheel is used to achieve acceptable levels of engine response. The package offers a 100 lb weight advantage in a Chrysler K Car front-wheel-drive installation. Initial layout studies, preliminary transient thermal analysis, ceramic inner housing structural analysis, and detailed performance analysis were carried out for the basic engine.

  5. Repairs of composite structures

    NASA Astrophysics Data System (ADS)

    Roh, Hee Seok

    Repair on damaged composite panels was conducted. To better understand adhesively bonded repair, the study investigates the effect of design parameters on the joint strength. The design parameters include bondline length, thickness of adherend and type of adhesive. Adhesives considered in this study were tested to measure their tensile material properties. Three types of adhesively bonded joints, single strap, double strap, and single lap joint were considered under changing bondline lengths, thickness of adherend and type of adhesive. Based on lessons learned from bonded joints, a one-sided patch repair method for composite structures was conducted. The composite patch was bonded to the damaged panel by either film adhesive FM-73M or paste adhesive EA-9394 and the residual strengths of the repaired specimens were compared under varying patch sizes. A new repair method using attachments has been suggested to enhance the residual strength. Results obtained through experiments were analyzed using finite element analysis to provide a better repair design and explain the experimental results. It was observed that the residual strength of the repaired specimen was affected by patch length. Method for rapid repairs of damaged composite structures was investigated. The damage was represented by a circular hole in a composite laminated plate. Pre-cured composite patches were bonded with a quick-curing commercial adhesive near (rather than over) the hole. Tensile tests were conducted on specimens repaired with various patch geometries. The test results showed that, among the methods investigated, the best repair method restored over 90% of the original strength of an undamaged panel. The interfacial stresses in the adhesive zone for different patches were calculated in order to understand the efficiencies of the designs of these patch repairs. It was found that the composite patch that yielded the best strength had the lowest interfacial peel stress between the patch and

  6. Snowmobile Repair. Teacher Edition.

    ERIC Educational Resources Information Center

    Hennessy, Stephen S.; Conrad, Rex

    This teacher's guide contains 14 units on snowmobile repair: (1) introduction to snowmobile repair; (2) skis, front suspension, and steering; (3) drive clutch; (4) drive belts; (5) driven clutch; (6) chain drives; (7) jackshafts and axles; (8) rear suspension; (9) tracks; (10) shock absorbers; (11) brakes; (12) engines; (13) ignition and…

  7. Chain Saw Repair.

    ERIC Educational Resources Information Center

    Taylor, Mark; Helbling, Wayne

    This curriculum is designed to supplement the Comprehensive Small Engine Repair guide by covering in detail all aspects of chain saw repair. The publication contains materials for both teacher and student and is written in terms of student performance using measurable objectives. The course includes six units. Each unit contains some or all of the…

  8. INTERNAL REPAIR OF PIPELINES

    SciTech Connect

    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

  9. INTERNAL REPAIR OF PIPELINES

    SciTech Connect

    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

  10. INTERNAL REPAIR OF PIPELINES

    SciTech Connect

    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

  11. Rapid road repair vehicle

    DOEpatents

    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.

  12. Brain aneurysm repair - discharge

    MedlinePlus

    ... gov/pubmed/22556195 . Szeder V, Tateshima S, Duckwiler GR. Intracranial aneurysms and subarachnoid hemorrhage. In: Daroff RB, Jankovic J, ... chap 67. Read More Aneurysm in the brain Brain aneurysm repair Brain surgery Recovering after stroke Seizures Smoking - ...

  13. Pectus excavatum repair

    MedlinePlus

    Gottlieb LJ, Reid RR, Lee JC. Pediatric chest and trunk defects. In: Neligan PC, ed. Plastic Surgery . 3rd ed. Philadelphia, PA: Elsevier; 2013:chap 41. Lumpkins KM, Colombani P, Abdullah F. Repair ...

  14. Diaphragmatic hernia repair - slideshow

    MedlinePlus

    ... presentations/100014.htm Diaphragmatic hernia repair - series—Normal anatomy To use the sharing ... Overview The chest cavity includes the heart and lungs. The abdominal cavity includes the liver, the stomach, ...

  15. Timpani Repair and Maintenance.

    ERIC Educational Resources Information Center

    Combs, F. Michael

    1980-01-01

    Rather than focusing on specific brands of timpani, these guidelines for repair cover mechanical problems of a general nature: pedals, dents, unclear tone, and squeaking. Preventive maintenance is discussed. (Author/SJL)

  16. INTERNAL REPAIR OF PIPELINES

    SciTech Connect

    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

  17. Hypospadias repair - discharge

    MedlinePlus

    ... Campbell-Walsh Urology . 10th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 130. Read More Hypospadias Hypospadias repair Kidney removal Review Date 1/21/2015 Updated by: Scott Miller, MD, Urologist in private practice in Atlanta, ...

  18. Meningocele repair - slideshow

    MedlinePlus

    ... ency/presentations/100128.htm Meningocele repair - series—Normal anatomy To use the sharing features on this page, ... Sinai Medical Center, Los Angeles and Department of Anatomy, University of California, San Francisco, CA. Review provided ...

  19. Achilles tendon repair

    MedlinePlus

    Achilles tendon rupture-surgery; Percutaneous Achilles tendon rupture repair ... To fix your torn Achilles tendon, the surgeon will: Make a cut down the back of your heel Make several small cuts rather than one large cut ...

  20. Bone fracture repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100077.htm Bone fracture repair - series—Indications To use the sharing features ... Go to slide 4 out of 4 Overview Fractures of the bones are classified in a number ...

  1. Femur fracture repair - discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000166.htm Femur fracture repair - discharge To use the sharing features on this page, please enable JavaScript. You had a fracture (break) in the femur in your leg. It ...

  2. Pectus excavatum repair - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100035.htm Pectus excavatum repair - series—Normal anatomy To use the sharing ... Go to slide 4 out of 4 Overview Pectus excavatum is a deformity of the front of the ...

  3. Eye muscle repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  4. Ventral hernia repair

    MedlinePlus

    ... Philadelphia. PA: Elsevier Saunders; 2014:539-545. Nagle AP, Soper NJ. Laparoscopic ventral hernia repair. In: Khatri ... Support Get email updates Subscribe to RSS Follow us Disclaimers Copyright Privacy Accessibility Quality Guidelines Viewers & Players ...

  5. Patent urachus repair

    MedlinePlus

    Patent urachal tube repair ... belly. Next, the surgeon will find the urachal tube and remove it. The bladder opening will be ... surgeon uses the tools to remove the urachal tube and close off the bladder and area where ...

  6. Imperforate anus repair - slideshow

    MedlinePlus

    ... presentations/100030.htm Imperforate anus repair - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  7. Rotator cuff repair - slideshow

    MedlinePlus

    ... presentations/100229.htm Rotator cuff repair - series—Normal anatomy To use the sharing features on this page, ... Bethesda, MD 20894 U.S. Department of Health and Human Services National Institutes of Health Page last updated: ...

  8. Carpal tunnel repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100078.htm Carpal tunnel repair - series—Normal anatomy To use the sharing ... in the wrist and the wrist bones (carpal tunnel). Review Date 5/9/2015 Updated by: C. ...

  9. Proximal Hamstring Repair Strength

    PubMed Central

    Harvey, Margaret Ann; Singh, Hardeep; Obopilwe, Elifho; Charette, Ryan; Miller, Suzanne

    2015-01-01

    Background: Proximal hamstring repair for complete ruptures has become a common treatment. There is no consensus in the literature about postoperative rehabilitation protocols following proximal hamstring repair. Some protocols describe bracing to prevent hip flexion or knee extension while others describe no immobilization. There are currently no biomechanical studies evaluating proximal hamstring repairs; nor are there any studies evaluating the effect of different hip flexion angles on these repairs. Hypothesis: As hip flexion increases from 0° to 90°, there will be a greater gap with cyclical loading. Study Design: Controlled laboratory study. Methods: Proximal hamstring insertions were detached from the ischial tuberosity in 24 cadavers and were repaired with 3 single-loaded suture anchors in the hamstring footprint with a Krakow suture technique. Cyclic loading from 10 to 125 N at 1 Hz was then performed for 0°, 45°, and 90° of hip flexion for 1500 cycles. Gap formation, stiffness, yield load, ultimate load, and energy to ultimate load were compared between groups using paired t tests. Results: Cyclic loading demonstrated the least amount of gap formation (P < .05) at 0° of hip flexion (2.39 mm) and most at 90° of hip flexion (4.19 mm). There was no significant difference in ultimate load between hip flexion angles (326, 309, and 338 N at 0°, 45°, and 90°, respectively). The most common mode of failure occurred with knot/suture failure (n = 17). Conclusion: Increasing hip flexion from 0° to 90° increases the displacement across proximal hamstring repairs. Postoperative bracing that limits hip flexion should be considered. Clinical Relevance: Repetitive motion involving hip flexion after a proximal hamstring repair may cause compromise of the repair. PMID:26665049

  10. Incisional hernia repair.

    PubMed

    Millikan, Keith W

    2003-10-01

    Incisional ventral hernias are a common problem encountered by surgeons, with over 100,000 repairs being performed annually in the United States. Although many predisposing factors for incisional ventral hernia are patient-related, some factors such as type of primary closure and materials used may reduce the overall incidence of incisional ventral hernia. With the advent of prosthetic meshes being used for incisional ventral hernia repair, the recurrence rate has dropped to approximately 10%. More recently, with the development of prosthetic mesh that is now safe to place intraperitoneally, the recurrence rate has dropped to under 5%. The current controversies that exist for incisional ventral hernia repair are which approach to use (open versus laparoscopic) and what type of fixation (partial- versus full-thickness abdominal muscular/fascial wall) is necessary to stabilize the position of the mesh while tissue ingrowth occurs. During the next decade the answers to these controversies should be available in the surgical literature.

  11. Rescheduling with iterative repair

    NASA Technical Reports Server (NTRS)

    Zweben, Monte; Davis, Eugene; Daun, Brian; Deale, Michael

    1992-01-01

    This paper presents a new approach to rescheduling called constraint-based iterative repair. This approach gives our system the ability to satisfy domain constraints, address optimization concerns, minimize perturbation to the original schedule, and produce modified schedules quickly. The system begins with an initial, flawed schedule and then iteratively repairs constraint violations until a conflict-free schedule is produced. In an empirical demonstration, we vary the importance of minimizing perturbation and report how fast the system is able to resolve conflicts in a given time bound. These experiments were performed within the domain of Space Shuttle ground processing.

  12. Rescheduling with iterative repair

    NASA Technical Reports Server (NTRS)

    Zweben, Monte; Davis, Eugene; Daun, Brian; Deale, Michael

    1992-01-01

    This paper presents a new approach to rescheduling called constraint-based iterative repair. This approach gives our system the ability to satisfy domain constraints, address optimization concerns, minimize perturbation to the original schedule, produce modified schedules, quickly, and exhibits 'anytime' behavior. The system begins with an initial, flawed schedule and then iteratively repairs constraint violations until a conflict-free schedule is produced. In an empirical demonstration, we vary the importance of minimizing perturbation and report how fast the system is able to resolve conflicts in a given time bound. We also show the anytime characteristics of the system. These experiments were performed within the domain of Space Shuttle ground processing.

  13. Investigations on the effect of O(6)-benzylguanine on the formation of dG-dC interstrand cross-links induced by chloroethylnitrosoureas in human glioma cells using stable isotope dilution high-performance liquid chromatography electrospray ionization tandem mass spectrometry.

    PubMed

    Sun, Guohui; Zhao, Lijiao; Fan, Tengjiao; Li, Sisi; Zhong, Rugang

    2014-07-21

    Chloroethylnitrosoureas (CENUs) are bifunctional alkylating agents widely used for the clinical treatment of cancer. They exert anticancer activity by inducing DNA interstrand cross-links (ICLs) within GC base pairs to form dG-dC cross-links. This lesion inhibits DNA double strand separation during replication and transcription and results in the apoptosis of cancer cells. However, O(6)-alkylguanine DNA alkyltransferase (AGT) repairs the DNA ICLs by removing the alkyl group at the O(6) position of either O(6)-(2-chloroethyl)deoxyguanosine (O(6)-ClEtdGuo) or N1,O(6)-ethanodeoxyguanosine (N1,O(6)-EtdGuo), which are intermediates in the formation of dG-dC cross-links. The action of AGT leads to drug resistance against CENUs. O(6)-Benzylguanine (O(6)-BG) was identified as an effective AGT inhibitor that enhances the antitumor effects of CENUs. In this study, the effect of O(6)-BG on the formation of dG-dC cross-links was investigated by treating human brain glioma SF767 cells with 1-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3-nitrosourea (ACNU). The levels of dG-dC cross-link were determined using stable isotope dilution high-performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS). The results indicated that ACNU induced higher levels of dG-dC cross-link in SF767 cells pretreated with O(6)-BG compared to cells without O(6)-BG pretreatment. The highest dG-dC cross-linking levels were generally observed at 12 h for all drug concentration groups, a result which was consistent with cytotoxicity assay. These results provided direct evidence for the enhancement of dG-dC cross-linking levels caused by the inhibition of AGT by O(6)-BG. These data indicate that dG-dC cross-links may be developed as a biomarker for evaluating the activity of novel O(6)-BG analogues as AGT inhibitors for combination therapy with CENUs.

  14. Electric motor model repair specifications

    SciTech Connect

    1995-08-01

    These model repair specifications list the minimum requirements for repair and overhaul of polyphase AC squireel cage induction motors. All power ranges, voltages, and speeds of squirrel cage motors are covered.

  15. Automotive Body Repair Competencies.

    ERIC Educational Resources Information Center

    D'Armond, Jack; And Others

    Designed to provide a model curriculum and guidelines, this manual presents tasks that were identified by employers, employees, and teachers as important in a postsecondary auto body repair curriculum. The tasks are divided into ten major component areas of instruction: metalworking and fiberglass, painting, frame and suspension, glass and trim,…

  16. Getting Ready To Repair.

    ERIC Educational Resources Information Center

    Stryker, Rick

    2002-01-01

    Successful camp repairs require careful planning. Prioritize projects by program needs first, then by cost. Determine the cause of deterioration and address it. Build goodwill with suppliers by knowing what you want and giving them ample time to prepare estimates. Include labor costs, even for staff labor. A cost-estimate table for a sample…

  17. Single cell wound repair

    PubMed Central

    Abreu-Blanco, Maria Teresa; Verboon, Jeffrey M

    2011-01-01

    Cell wounding is a common event in the life of many cell types, and the capacity of the cell to repair day-to-day wear-and-tear injuries, as well as traumatic ones, is fundamental for maintaining tissue integrity. Cell wounding is most frequent in tissues exposed to high levels of stress. Survival of such plasma membrane disruptions requires rapid resealing to prevent the loss of cytosolic components, to block Ca2+ influx and to avoid cell death. In addition to patching the torn membrane, plasma membrane and cortical cytoskeleton remodeling are required to restore cell function. Although a general understanding of the cell wound repair process is in place, the underlying mechanisms of each step of this response are not yet known. We have developed a model to study single cell wound repair using the early Drosophila embryo. Our system combines genetics and live imaging tools, allowing us to dissect in vivo the dynamics of the single cell wound response. We have shown that cell wound repair in Drosophila requires the coordinated activities of plasma membrane and cytoskeleton components. Furthermore, we identified an unexpected role for E-cadherin as a link between the contractile actomyosin ring and the newly formed plasma membrane plug. PMID:21922041

  18. Aircraft Propeller Hub Repair

    SciTech Connect

    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.

  19. Hydrocele repair - slideshow

    MedlinePlus

    ... anatomy URL of this page: //medlineplus.gov/ency/presentations/100163.htm Hydrocele repair - series—Normal anatomy To use the sharing features on this page, please enable JavaScript. Go to slide 1 out of 4 Go to slide 2 ...

  20. Eardrum repair - slideshow

    MedlinePlus

    ... anatomy URL of this page: //medlineplus.gov/ency/presentations/100015.htm Eardrum repair - series—Normal anatomy To use the sharing features on this page, please enable JavaScript. Go to slide 1 out of 4 Go to slide 2 ...

  1. Comprehensive Small Engine Repair.

    ERIC Educational Resources Information Center

    Hires, Bill; And Others

    This curriculum guide contains the basic information needed to repair all two- and four-stroke cycle engines. The curriculum covers four areas, each consisting of one or more units of instruction that include performance objectives, suggested activities for teacher and students, information sheets, assignment sheets, job sheets, visual aids,…

  2. Hiatal hernia repair - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100028.htm Hiatal hernia repair - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Hiatal Hernia A.D.A.M., Inc. is accredited by ...

  3. Basic Book Repair Methods.

    ERIC Educational Resources Information Center

    Schechter, Abraham A.

    This book addresses some common preservation techniques that invariably become necessary in library and archival collections of any size. The procedures are described in chronological sequence, and photographs show the techniques from the viewpoint of the person actually doing the work. The recommended repair methods can be accomplished using…

  4. Intestinal obstruction repair - slideshow

    MedlinePlus

    ... this page: //medlineplus.gov/ency/presentations/100116.htm Intestinal obstruction repair - series—Normal anatomy To use the sharing ... M. Editorial team. Related MedlinePlus Health Topics Adhesions Intestinal Obstruction A.D.A.M., Inc. is accredited by ...

  5. Lawn and Garden Equipment Repair.

    ERIC Educational Resources Information Center

    Hardway, Jack; And Others

    This publication is designed to supplement the Comprehensive Small Engine Rapair guide by covering in detail all aspects of lawn and garden equipment repair not included in general engine repair or the repair of other small engines. It consists of instructional materials for both teachers and students, written in terms of student performance using…

  6. Laparoscopic repair of femoral hernia

    PubMed Central

    Yang, Xue-Fei

    2016-01-01

    Laparoscopic repair of inguinal hernia is mini-invasive and has confirmed effects. Femoral hernia could be repaired through the laparoscopic procedures for inguinal hernia. These procedures have clear anatomic view in the operation and preoperatively undiagnosed femoral hernia could be confirmed and treated. Lower recurrence ratio was reported in laparoscopic procedures compared with open procedures for repair of femoral hernia. The technical details of laparoscopic repair of femoral hernia, especially the differences to laparoscopic repair of inguinal hernia are discussed in this article. PMID:27826574

  7. Minimally Invasive Spigelian Hernia Repair

    PubMed Central

    Baucom, Catherine; Nguyen, Quan D.; Hidalgo, Marco

    2009-01-01

    Introduction: Spigelian hernia is an uncommon ventral hernia characterized by a defect in the linea semilunaris. Repair of spigelian hernia has traditionally been accomplished via an open transverse incision and primary repair. The purpose of this article is to present 2 case reports of incarcerated spigelian hernia that were successfully repaired laparoscopically using Gortex mesh and to present a review of the literature regarding laparoscopic repair of spigelian hernias. Methods: Retrospective chart review and Medline literature search. Results: Two patients underwent laparoscopic mesh repair of incarcerated spigelian hernias. Both were started on a regular diet on postoperative day 1 and discharged on postoperative days 2 and 3. One patient developed a seroma that resolved without intervention. There was complete resolution of preoperative symptoms at the 12-month follow-up. Conclusion: Minimally invasive repair of spigelian hernias is an alternative to the traditional open surgical technique. Further studies are needed to directly compare the open and the laparoscopic repair. PMID:19660230

  8. Rapid Runway Repair Study.

    DTIC Science & Technology

    This report describes a series of tests to evaluate a system for rapidly repairing airfield pavement using polymer concrete (synthetic polymer plus...aggregate), thermally cured by microwave power. The technique, developed by the Syracuse University Research Corporation (SURC) for highway...maintenance, uses a truck-mounted 50-kilowatt microwave generator to irradiate areas patched with polymer concrete . Test results indicate that the polymer

  9. DNA excision repair at telomeres.

    PubMed

    Jia, Pingping; Her, Chengtao; Chai, Weihang

    2015-12-01

    DNA damage is caused by either endogenous cellular metabolic processes such as hydrolysis, oxidation, alkylation, and DNA base mismatches, or exogenous sources including ultraviolet (UV) light, ionizing radiation, and chemical agents. Damaged DNA that is not properly repaired can lead to genomic instability, driving tumorigenesis. To protect genomic stability, mammalian cells have evolved highly conserved DNA repair mechanisms to remove and repair DNA lesions. Telomeres are composed of long tandem TTAGGG repeats located at the ends of chromosomes. Maintenance of functional telomeres is critical for preventing genome instability. The telomeric sequence possesses unique features that predispose telomeres to a variety of DNA damage induced by environmental genotoxins. This review briefly describes the relevance of excision repair pathways in telomere maintenance, with the focus on base excision repair (BER), nucleotide excision repair (NER), and mismatch repair (MMR). By summarizing current knowledge on excision repair of telomere damage and outlining many unanswered questions, it is our hope to stimulate further interest in a better understanding of excision repair processes at telomeres and in how these processes contribute to telomere maintenance.

  10. DNA repair in cultured keratinocytes

    SciTech Connect

    Liu, S.C.; Parsons, S.; Hanawalt, P.C.

    1983-07-01

    Most of our understanding of DNA repair mechanisms in human cells has come from the study of these processes in cultured fibroblasts. The unique properties of keratinocytes and their pattern of terminal differentiation led us to a comparative examination of their DNA repair properties. The relative repair capabilities of the basal cells and the differentiated epidermal keratinocytes as well as possible correlations of DNA repair capacity with respect to age of the donor have been examined. In addition, since portions of human skin are chronically exposed to sunlight, the repair response to ultraviolet (UV) irradiation (254 nm) when the cells are conditioned by chronic low-level UV irradiation has been assessed. The comparative studies of DNA repair in keratinocytes from infant and aged donors have revealed no significant age-related differences for repair of UV-induced damage to DNA. Sublethal UV conditioning of cells from infant skin had no appreciable effect on either the repair or normal replication response to higher, challenge doses of UVL. However, such conditioning resulted in attenuated repair in keratinocytes from adult skin after UV doses above 25 J/m2. In addition, a surprising enhancement in replication was seen in conditioned cells from adult following challenge UV doses.

  11. Stimulating endogenous cardiac repair

    PubMed Central

    Finan, Amanda; Richard, Sylvain

    2015-01-01

    The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration, a combination of these approaches could ameliorate the overall repair process to incorporate the participation of multiple cellular players. PMID:26484341

  12. Industrial motor repair in the United States

    SciTech Connect

    Schueler, V.; Leistner, P.; Douglass, J.

    1994-09-01

    This report characterizes the motor repair industry in the United States; summarizes current motor repair and testing practice; and identifies barriers to energy motor repair practice and recommends strategies for overcoming those barriers.

  13. 40 CFR 63.1005 - Leak repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... emissions of purged material resulting from immediate repair would be greater than the fugitive emissions likely to result from delay of repair, and (ii) When repair procedures are effected, the purged...

  14. 40 CFR 63.1024 - Leak repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... purged material resulting from immediate repair would be greater than the fugitive emissions likely to result from delay of repair, and (ii) When repair procedures are effected, the purged material...

  15. Membrane Repair: Mechanisms and Pathophysiology

    PubMed Central

    Cooper, Sandra T.; McNeil, Paul L.

    2015-01-01

    Eukaryotic cells have been confronted throughout their evolution with potentially lethal plasma membrane injuries, including those caused by osmotic stress, by infection from bacterial toxins and parasites, and by mechanical and ischemic stress. The wounded cell can survive if a rapid repair response is mounted that restores boundary integrity. Calcium has been identified as the key trigger to activate an effective membrane repair response that utilizes exocytosis and endocytosis to repair a membrane tear, or remove a membrane pore. We here review what is known about the cellular and molecular mechanisms of membrane repair, with particular emphasis on the relevance of repair as it relates to disease pathologies. Collective evidence reveals membrane repair employs primitive yet robust molecular machinery, such as vesicle fusion and contractile rings, processes evolutionarily honed for simplicity and success. Yet to be fully understood is whether core membrane repair machinery exists in all cells, or whether evolutionary adaptation has resulted in multiple compensatory repair pathways that specialize in different tissues and cells within our body. PMID:26336031

  16. Instructional Guide for Autobody Repair.

    ERIC Educational Resources Information Center

    Virginia Polytechnic Inst. and State Univ., Blacksburg. Dept. of Education.

    The curriculum guide was developed to serve as a statewide model for Virginia auto body repair programs. The guide is designed to 1,080 hours of instruction in eleven blocks: orientation, introduction, welding and cutting, techniques of shaping metal, body filler and fiberglass repairs, body and frame, removing and replacing damaged parts, basic…

  17. Major Appliance Repair. Teacher Edition.

    ERIC Educational Resources Information Center

    Smreker, Eugene; Calvert, King

    This module is a comprehensive text on basic appliance repair, designed to prepare students for entry-level jobs in this growing field. Ensuring a firm grounding in electrical knowledge, the module contains 13 instructional units that cover the following topics: (1) major appliance repair orientation; (2) safety and first aid; (3) fundamentals of…

  18. Pipe inspection and repair system

    NASA Technical Reports Server (NTRS)

    Schempf, Hagen (Inventor); Mutschler, Edward (Inventor); Chemel, Brian (Inventor); Boehmke, Scott (Inventor); Crowley, William (Inventor)

    2004-01-01

    A multi-module pipe inspection and repair device. The device includes a base module, a camera module, a sensor module, an MFL module, a brush module, a patch set/test module, and a marker module. Each of the modules may be interconnected to construct one of an inspection device, a preparation device, a marking device, and a repair device.

  19. Small Crater Expedient Repair Test.

    DTIC Science & Technology

    1980-08-01

    Crater 4, the timed polymer-concrete repair, failed due to material quality. An estimated 20 of the 464 bags of SilikalO lacked the benzoyl ... peroxide catalyst required for polymerization. As a result of this omission, several areas of the repair failed to harden, causing the unpolymerized mateiial

  20. Rethinking transcription coupled DNA repair.

    PubMed

    Kamarthapu, Venu; Nudler, Evgeny

    2015-04-01

    Nucleotide excision repair (NER) is an evolutionarily conserved, multistep process that can detect a wide variety of DNA lesions. Transcription coupled repair (TCR) is a subpathway of NER that repairs the transcribed DNA strand faster than the rest of the genome. RNA polymerase (RNAP) stalled at DNA lesions mediates the recruitment of NER enzymes to the damage site. In this review we focus on a newly identified bacterial TCR pathway in which the NER enzyme UvrD, in conjunction with NusA, plays a major role in initiating the repair process. We discuss the tradeoff between the new and conventional models of TCR, how and when each pathway operates to repair DNA damage, and the necessity of pervasive transcription in maintaining genome integrity.

  1. Laparoscopic repair of recurrent hernias.

    PubMed

    Felix, E L; Michas, C A; McKnight, R L

    1995-02-01

    The purpose of this study was to evaluate the results of a laparoscopic approach to recurrent inguinal hernia repair which dissected the entire inguinal floor and repaired all potential areas of recurrence without producing tension. Both a transabdominal preperitoneal and a totally extraperitoneal laparoscopic approach were utilized. Ninety recurrent hernias were repaired in 81 patients. The patients had 26 indirect, 36 direct, and 26 pantaloon recurrent hernias of which eight had a femoral component. In all but one patient the primary operations were open anterior repairs. The median follow-up was 14 months, ranging from 1 to 28 months. Patients returned to normal activities in an average of 1 week. The only recurrence observed was in the one patient whose primary repair was laparoscopic. When the entire inguinal floor of the recurrent hernia was redissected and buttressed with mesh, early recurrence was eliminated and recovery was shortened.

  2. Wound repair in Pocillopora

    USGS Publications Warehouse

    Rodríguez-Villalobos, Jenny Carolina; Work, Thierry M.; Calderon-Aguileraa, Luis Eduardo

    2016-01-01

    Corals routinely lose tissue due to causes ranging from predation to disease. Tissue healing and regeneration are fundamental to the normal functioning of corals, yet we know little about this process. We described the microscopic morphology of wound repair in Pocillopora damicornis. Tissue was removed by airbrushing fragments from three healthy colonies, and these were monitored daily at the gross and microscopic level for 40 days. Grossly, corals healed by Day 30, but repigmentation was not evident at the end of the study (40 d). On histology, from Day 8 onwards, tissues at the lesion site were microscopically indistinguishable from adjacent normal tissues with evidence of zooxanthellae in gastrodermis. Inflammation was not evident. P. damicornis manifested a unique mode of regeneration involving projections of cell-covered mesoglea from the surface body wall that anastomosed to form gastrovascular canals.

  3. TPS Inspection and Repair

    NASA Technical Reports Server (NTRS)

    Parazynski, Scott

    2012-01-01

    Dr. Scott Parazynski provided a retrospective on the EVA tools and procedures efforts NASA went through in the aftermath of Columbia for the Shuttle Thermal Protection System (TPS) inspection and repair. He describes his role as the lead astronaut on this effort, and covered all of the Neutral Buoyancy Lab (NBL), KC 135 (reduced gravity aircraft), Precision Air Bearing Floor (PABF), vacuum chamber and 1 G testing that was done in order to develop the tools and techniques that were flown. Parazynski also discusses how the EVA community worked together to resolve a huge safety issue, and how his work in the spacesuit was critical to overcoming a design limitation of the Space Shuttle.

  4. Wound repair in Pocillopora.

    PubMed

    Rodríguez-Villalobos, Jenny Carolina; Work, Thierry Martin; Calderon-Aguilera, Luis Eduardo

    2016-09-01

    Corals routinely lose tissue due to causes ranging from predation to disease. Tissue healing and regeneration are fundamental to the normal functioning of corals, yet we know little about this process. We described the microscopic morphology of wound repair in Pocillopora damicornis. Tissue was removed by airbrushing fragments from three healthy colonies, and these were monitored daily at the gross and microscopic level for 40days. Grossly, corals healed by Day 30, but repigmentation was not evident at the end of the study (40d). On histology, from Day 8 onwards, tissues at the lesion site were microscopically indistinguishable from adjacent normal tissues with evidence of zooxanthellae in gastrodermis. Inflammation was not evident. P. damicornis manifested a unique mode of regeneration involving projections of cell-covered mesoglea from the surface body wall that anastomosed to form gastrovascular canals.

  5. How to repair an episiotomy.

    PubMed

    Steen, Mary; Cummins, Bernie

    2016-02-17

    Rationale and key points Skilful repair of an episiotomy is an important aspect of maternal health care. It is essential that midwives and doctors have the knowledge and skills to undertake this procedure in a safe and effective manner. ▶ An episiotomy should be repaired promptly to reduce blood loss and prevent infection. ▶ Repair of an episiotomy is undertaken in three stages: repair of the vaginal mucosa, repair of the muscle layer and repair of the skin layer. ▶ Adequate pain relief should be provided before suturing. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. Why a rectal examination is recommended before and following repair of an episiotomy. 2. What you would do to improve your suturing skills. 3. The factors that may prevent or delay an episiotomy from healing. Subscribers can upload their reflective accounts at rcni.com/portfolio .

  6. Bone repair and stem cells.

    PubMed

    Ono, Noriaki; Kronenberg, Henry M

    2016-10-01

    Bones are an important component of vertebrates; they grow explosively in early life and maintain their strength throughout life. Bones also possess amazing capabilities to repair-the bone is like new without a scar after complete repair. In recent years, a substantial progress has been made in our understanding on mammalian bone stem cells. Mouse genetic models are powerful tools to understand the cell lineage, giving us better insights into stem cells that regulate bone growth, maintenance and repair. Recent findings about these stem cells raise new questions that require further investigations.

  7. Repair Types, Procedures - Part 2

    DTIC Science & Technology

    2010-05-01

    acceptable only if at least one undamaged flange remains in the existing internal structure. Sandwich repairs using extrusions or formed parts are better...easily be affected by bridging the damage with two L-angle extrusions fastened together through undamaged portions of the existing rod to form a ‘splint...Cell Repairs Rubber fuel bladders with damage less than 3 inches/7.6 cm can be repaired in a manner similar to patching tire inner-tubes using Buna-N

  8. 46 CFR Sec. 19 - Ship Repair Summaries.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Ship Repair Summaries. Sec. 19 Section 19 Shipping... Sec. 19 Ship Repair Summaries. (a) Ship Repair Summaries shall be prepared on Form MA-159 by the... jurisdiction and submitted to the District Ship Repair and Maintenance office involved. The summaries must...

  9. 46 CFR Sec. 19 - Ship Repair Summaries.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Ship Repair Summaries. Sec. 19 Section 19 Shipping... Sec. 19 Ship Repair Summaries. (a) Ship Repair Summaries shall be prepared on Form MA-159 by the... jurisdiction and submitted to the District Ship Repair and Maintenance office involved. The summaries must...

  10. 46 CFR Sec. 19 - Ship Repair Summaries.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Ship Repair Summaries. Sec. 19 Section 19 Shipping... Sec. 19 Ship Repair Summaries. (a) Ship Repair Summaries shall be prepared on Form MA-159 by the... jurisdiction and submitted to the District Ship Repair and Maintenance office involved. The summaries must...

  11. 46 CFR Sec. 19 - Ship Repair Summaries.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Ship Repair Summaries. Sec. 19 Section 19 Shipping... Sec. 19 Ship Repair Summaries. (a) Ship Repair Summaries shall be prepared on Form MA-159 by the... jurisdiction and submitted to the District Ship Repair and Maintenance office involved. The summaries must...

  12. 46 CFR Sec. 19 - Ship Repair Summaries.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Ship Repair Summaries. Sec. 19 Section 19 Shipping... Sec. 19 Ship Repair Summaries. (a) Ship Repair Summaries shall be prepared on Form MA-159 by the... jurisdiction and submitted to the District Ship Repair and Maintenance office involved. The summaries must...

  13. Aortic aneurysm repair - endovascular- discharge

    MedlinePlus

    ... MRI scan Aortic aneurysm repair - endovascular Aortic angiography Hardening of ... Center-Shreveport, Shreveport, LA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla ...

  14. Biologic scaffold for CNS repair.

    PubMed

    Meng, Fanwei; Modo, Michel; Badylak, Stephen F

    2014-05-01

    Injury to the CNS typically results in significant morbidity and endogenous repair mechanisms are limited in their ability to restore fully functional CNS tissue. Biologic scaffolds composed of individual purified components have been shown to facilitate functional tissue reconstruction following CNS injury. Extracellular matrix scaffolds derived from mammalian tissues retain a number of bioactive molecules and their ability for CNS repair has recently been recognized. In addition, novel biomaterials for dural mater repairs are of clinical interest as the dura provides barrier function and maintains homeostasis to CNS. The present article describes the application of regenerative medicine principles to the CNS tissues and dural mater repair. While many approaches have been exploring the use of cells and/or therapeutic molecules, the strategies described herein focus upon the use of extracellular matrix scaffolds derived from mammalian tissues that are free of cells and exogenous factors.

  15. Mammalian DNA Repair. Final Report

    SciTech Connect

    2003-01-24

    The Gordon Research Conference (GRC) on Mammalian DNA Repair was held at Harbortown Resort, Ventura Beach, CA. Emphasis was placed on current unpublished research and discussion of the future target areas in this field.

  16. Nucleotide excision repair in humans.

    PubMed

    Spivak, Graciela

    2015-12-01

    The demonstration of DNA damage excision and repair replication by Setlow, Howard-Flanders, Hanawalt and their colleagues in the early 1960s, constituted the discovery of the ubiquitous pathway of nucleotide excision repair (NER). The serial steps in NER are similar in organisms from unicellular bacteria to complex mammals and plants, and involve recognition of lesions, adducts or structures that disrupt the DNA double helix, removal of a short oligonucleotide containing the offending lesion, synthesis of a repair patch copying the opposite undamaged strand, and ligation, to restore the DNA to its original form. The transcription-coupled repair (TCR) subpathway of NER, discovered nearly two decades later, is dedicated to the removal of lesions from the template DNA strands of actively transcribed genes. In this review I will outline the essential factors and complexes involved in NER in humans, and will comment on additional factors and metabolic processes that affect the efficiency of this important process.

  17. Nucleotide excision repair in humans

    PubMed Central

    Spivak, Graciela

    2015-01-01

    The demonstration of DNA damage excision and repair replication by Setlow, Howard-Flanders, Hanawalt and their colleagues in the early 1960s, constituted the discovery of the ubiquitous pathway of nucleotide excision repair (NER). The serial steps in NER are similar in organisms from unicellular bacteria to complex mammals and plants, and involve recognition of lesions, adducts or structures that disrupt the DNA double helix, removal of a short oligonucleotide containing the offending lesion, synthesis of a repair patch copying the opposite undamaged strand, and ligation, to restore the DNA to its original form. The transcription-coupled repair (TCR) subpathway of NER, discovered nearly two decades later, is dedicated to the removal of lesions from the template DNA strands of actively transcribed genes. In this review I will outline the essential factors and complexes involved in NER in humans, and will comment on additional factors and metabolic processes that affect the efficiency of this important process. PMID:26388429

  18. Precision Instrument and Equipment Repairers.

    ERIC Educational Resources Information Center

    Wyatt, Ian

    2001-01-01

    Explains the job of precision instrument and equipment repairers, who work on cameras, medical equipment, musical instruments, watches and clocks, and industrial measuring devices. Discusses duties, working conditions, employment and earnings, job outlook, and skills and training. (JOW)

  19. Early days of DNA repair: discovery of nucleotide excision repair and homology-dependent recombinational repair.

    PubMed

    Rupp, W Dean

    2013-12-13

    The discovery of nucleotide excision repair in 1964 showed that DNA could be repaired by a mechanism that removed the damaged section of a strand and replaced it accurately by using the remaining intact strand as the template. This result showed that DNA could be actively metabolized in a process that had no precedent. In 1968, experiments describing postreplication repair, a process dependent on homologous recombination, were reported. The authors of these papers were either at Yale University or had prior Yale connections. Here we recount some of the events leading to these discoveries and consider the impact on further research at Yale and elsewhere.

  20. Aircraft Metal Skin Repair and Honeycomb Structure Repair; Sheet Metal Work 3: 9857.02.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    The course helps students determine types of repairs, compute repair sizes, and complete the repair through surface protection. Course content includes goals, specific objectives, protection of metals, repairs to metal skin, and honeycomb structure repair. A bibliography and post-test are appended. A prerequisite for this course is mastery of the…

  1. Rehabilitation after Rotator Cuff Repair

    PubMed Central

    Nikolaidou, Ourania; Migkou, Stefania; Karampalis, Christos

    2017-01-01

    Background: Rotator cuff tears are a very common condition that is often incapacitating. Whether non-surgical or surgical, successful management of rotator cuff disease is dependent on appropriate rehabilitation. If conservative management is insufficient, surgical repair is often indicated. Postsurgical outcomes for patients having had rotator cuff repair can be quite good. A successful outcome is much dependent on surgical technique as it is on rehabilitation. Numerous rehabilitation protocols for the management of rotator cuff disease are based primarily on clinical experience and expert opinion. This article describes the different rehabilitation protocols that aim to protect the repair in the immediate postoperative period, minimize postoperative stiffness and muscle atrophy. Methods: A review of currently available literature on rehabilitation after arthroscopic rotator cuff tear repair was performed to illustrate the available evidence behind various postoperative treatment modalities. Results: There were no statistically significant differences between a conservative and an accelerated rehabilitation protocol . Early passive range of motion (ROM) following arthroscopic cuff repair is thought to decrease postoperative stiffness and improve functionality. However, early aggressive rehabilitation may compromise repair integrity. Conclusion: The currently available literature did not identify any significant differences in functional outcomes and relative risks of re-tears between delayed and early motion in patients undergoing arthroscopic rotator cuff repairs. A gentle rehabilitation protocol with limits in range of motion and exercise times after arthroscopic rotator cuff repair would be better for tendon healing without taking any substantial risks. A close communication between the surgeon, the patient and the physical therapy team is important and should continue throughout the whole recovery process.

  2. Shotcrete for Expedient Structural Repair

    DTIC Science & Technology

    1991-12-01

    AD-A260 788 ESL-TR-90-14 SHOTCRETE FOR EXPEDIENT STRUCTURAL REPAIR 4t ’Pit at MARK ANDERSON APPLIED RESEARCH ASSOCIATES, INC. P.O. BOX 40128...SUBTITrrLE S. FUNDING NUMBERS Shotcrete for Expedient Structural Repair 4. AUTHOR(S) F08635-88-C-0067 Anderson, Mark 7. PERFORMING ORGANIZATION NAME(S) AND...AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE Approved for public release. Distribution unlimited. 13. ABSTRACT (Maximum 200 words) Shotcrete , or

  3. Durability of Expedient Repair Materials

    DTIC Science & Technology

    1993-03-01

    by the Flofida Department of Transportation. I&. SUWIUET" TERMS 󈧓. NUMBER OF 1A1ES Expedient Repair Materials 21PAGE Shotcrete Air Force Base...produced by CTS Cemem Company. A dry process shotcrete standard, MicrosilR, and a State of Florida corrosion - resistant concrete system, referred to as...34 durability of the rapid repair materials tested by conventional methods for determining durability. E. CONCLUSIONS The blended Rapid-SetR shotcrete system

  4. Arthroscopic revision of Bankart repair.

    PubMed

    Neri, Brian R; Tuckman, David V; Bravman, Jonathan T; Yim, Duke; Sahajpal, Deenesh T; Rokito, Andrew S

    2007-01-01

    The success of revision surgery for failed Bankart repair is not well known. This purpose of this study was to report the success rates achieved using arthroscopic techniques to revise failed Bankart repairs. Twelve arthroscopic revision Bankart repairs were performed on patients with recurrent unidirectional shoulder instability after open or arthroscopic Bankart repair. Follow-up was available on 11 of the 12 patients at a mean of 34.4 months (range, 25-56 months). The surgical findings, possible modes of failure, shoulder scores (Rowe score, University of California Los Angeles [UCLA], Simple Shoulder Test), and clinical outcome were evaluated. Various modes of failure were recognized during revision arthroscopic Bankart repairs. Good-to-excellent results were obtained in 8 patients (73%) undergoing revision stabilization according to Rowe and UCLA scoring. A subluxation or dislocation event occurred in 3 (27%) of the 11 patients at a mean of 8.7 months (range, 6-12 months) postoperatively. Arthroscopic revision Bankart repairs are technically challenging procedures but can be used to achieve stable, pain-free, functional shoulders with return to prior sport. Owing to limited follow-up and the small number of patients in this study, we were unable to conclude any pattern of failure or selection criteria for this procedure.

  5. Parastomal hernia repair. An update.

    PubMed

    Wara, P

    2011-04-01

    Repair of parastomal hernia remains controversial. Open suture repair of the fascial defect or stoma resiting are both associated with high morbidity and unacceptably high recurrence rates and are no longer recommended for routine use. Mesh repair appears to provide the best results. Following the first anectodal reports there are accumulating evidence that laparoscopic mesh repair is feasible and has a promising potential in the management of parastomal hernia. Two laparoscopic techniques have emerged, the use of a mesh with a slit and a central keyhole and a mesh without a slit, the latter often termed as a modified Sugarbaker. Published series, however, are observational and often with a short length of follow-up. Most series suffer from small sample size and controlled trials are lacking. The limited data, therefore, make it difficult to draw conclusions. At present none of the methods of open or laparoscopic mesh repair has proved superior. In spite of this laparoscopic repair has gained increasing acceptance. A polypropylene based mesh with an anti-adhesive layer covering the visceral side seems to be applicable using the keyhole technique with a slit as well as the modified Sugarbaker technique. A PTFE mesh should preferably be used with the modified Sugarbaker technique. If a PTFE mesh is used with the keyhole technique parastomal hernia is likely to recur.

  6. Results of arthroscopic meniscal repair

    PubMed Central

    Orlowski, María Belén; Arroquy, Damián; Chahla, Jorge; Guiñazú, Jorge; Bisso, Martín Carboni; Vilaseca, Tomás

    2017-01-01

    Objectives: Currently the arthroscopic treatment of meniscal pathology has become one of the most common procedures in orthopedic practice and although in most cases meniscectomy is done, meniscal sutures are the treatment of choice when a reparable lesion is diagnosed, especially in young patients. It has been reported that the meniscal repair leads to a lower incidence of developing degenerative changes in the long-term when compared with meniscectomy and nonsurgical treatment of meniscal injuries. The aim of this study was to determine the success rate of meniscal repair achieved in our sports medicine practice. Methods: Between 2006 and 2015, 62 meniscal tears in 58 patients with a mean age of 31 years (range 15-58) were repaired. Mean follow-up was 52 months (range 6-120 months). In 16 patients (28%) was associated with arthroscopic ACL reconstruction. The repair techniques used included outside-in sutures, inside-out sutures, all-inside sutures and a combination of techniques. Failure of the repair was defined by the requirement for repeat knee arthroscopy and partial or subtotal meniscectomy. The indication of arthroscopic revision was based on the presence of mechanical symptoms, after the suture. Results: Failure of meniscus repair occurred in four patients (failure rate: 6.45%), one case was associated with ACL reconstruction (failure rate: 6.25%) and 3 had undergone isolated meniscal suture (failure rate: 8%). The average time for the reoperation was 15 months (4-24). We had no intraoperative complications. Conclusion: The reported failure rate of meniscal repair in stable knees varies between 12% and 43%, with reports that demonstrate a clinical success rate of 100%. In this study, we obtained a success rate of 93.5%. These results are slightly higher than those in the literature, which can be attributed to careful selection of patients and the fact that clinical success tends to be better than the assessed arthroscopically. In summary, we consider the

  7. Advanced Gas Turbine (AGT) Technology Project

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Technical work on the design and effort leading to the testing of a 74.5 kW (100 hp) automotive gas turbine engine is reviewed. Development of the engine compressor, gasifier turbine, power turbine, combustor, regenerator, and secondary system is discussed. Ceramic materials development and the application of such materials in the gas turbine engine components is described.

  8. Advanced Gas Turbine (AGT) powertrain system

    NASA Technical Reports Server (NTRS)

    Helms, H. E.; Kaufeld, J.; Kordes, R.

    1981-01-01

    A 74.5 kW(100 hp) advanced automotive gas turbine engine is described. A design iteration to improve the weight and production cost associated with the original concept is discussed. Major rig tests included 15 hours of compressor testing to 80% design speed and the results are presented. Approximately 150 hours of cold flow testing showed duct loss to be less than the design goal. Combustor test results are presented for initial checkout tests. Turbine design and rig fabrication is discussed. From a materials study of six methods to fabricate rotors, two have been selected for further effort. A discussion of all six methods is given.

  9. Advanced Gas Turbine (AGT) technology development

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A 74.5 kW (100 hp) automotive gas turbine was evaluated. The engine structure, bearings, oil system, and electronics were demonstrated and no shaft dynamics or other vibration problem were encountered. Areas identified during the five tests are the scroll retention features, and transient thermal deflection of turbine backplates. Modifications were designed. Seroll retention is addressed by modifying the seal arrangement in front of the gasifier turbine assembly, which will increase the pressure load on the scroll in the forward direction and thereby increase the retention forces. the backplate thermal deflection is addressed by geometric changes and thermal insulation to reduce heat input. Combustor rig proof testing of two ceramic combustor assemblies was completed. The combustor was modified to incorporate slots and reduce sharp edges, which should reduce thermal stresses. The development work focused on techniques to sinter these barrier materials onto the ceramic rotors with successes for both material systems. Silicon carbide structural parts, including engine configuration gasifier rotors (ECRs), preliminary gasifier scroll parts, and gasifier and power turbine vanes are fabricated.

  10. Algorithms for treating redundancy in repairable and non-repairable systems

    SciTech Connect

    Campbell, J.E.; Longsine, D.E.; Atkins, J.

    1993-10-01

    This report presents equations and computational algorithms for analyzing reliability of several forms of redundancy in repairable and non-repairable systems. For repairable systems, active, standby, and R of N redundancy with and without repair are treated. For non-repairable systems, active, standby, and R of N redundancy are addressed. These equations can be used to calculate mean time between failures, mean time to repair, and reliability for complex systems involving redundancy.

  11. The design of repairable advanced composite structures

    NASA Technical Reports Server (NTRS)

    Hart-Smith, L. J.

    1985-01-01

    This paper addresses the repair of advanced composite structures by mechanical fasteners or by adhesive bonding. It is shown that many of today's composite designs are unreasonably difficult to repair. Conversely, the knowledge to design repairable structures is already available, if only it is applied during the initial design stage. Bolted or riveted repairs require only the avoidance of extremely orthotropic composite fiber patterns; those near the quasi-isotropic layup are the most suitable. Mildly orthotropic fiber patterns are appropriate for structures in which there is a dominant load direction. Thick composite structures are shown to require bolted or riveted repairs while thin structures favor adhesively bonded permanent repairs, although provisions can be easily made for temporary mechanical repairs. The reasons why integrally stiffened cocured composite designs are usually impractical to repair are explained and alternative repairable design concepts are presented.

  12. 40 CFR 798.5500 - Differential growth inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... repair proficient and repair deficient bacteria: âBacterial DNA damage or repair tests.â 798.5500 Section... inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA damage or repair tests.” (a) Purpose. Bacterial DNA damage or repair tests measure DNA damage which is expressed as differential...

  13. 40 CFR 798.5500 - Differential growth inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... repair proficient and repair deficient bacteria: âBacterial DNA damage or repair tests.â 798.5500 Section... inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA damage or repair tests.” (a) Purpose. Bacterial DNA damage or repair tests measure DNA damage which is expressed as differential...

  14. 40 CFR 798.5500 - Differential growth inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... repair proficient and repair deficient bacteria: âBacterial DNA damage or repair tests.â 798.5500 Section... inhibition of repair proficient and repair deficient bacteria: “Bacterial DNA damage or repair tests.” (a) Purpose. Bacterial DNA damage or repair tests measure DNA damage which is expressed as differential...

  15. Essentials of skin laceration repair.

    PubMed

    Forsch, Randall T

    2008-10-15

    Skin laceration repair is an important skill in family medicine. Sutures, tissue adhesives, staples, and skin-closure tapes are options in the outpatient setting. Physicians should be familiar with various suturing techniques, including simple, running, and half-buried mattress (corner) sutures. Although suturing is the preferred method for laceration repair, tissue adhesives are similar in patient satisfaction, infection rates, and scarring risk in low skin-tension areas and may be more cost-effective. The tissue adhesive hair apposition technique also is effective in repairing scalp lacerations. The sting of local anesthesia injections can be lessened by using smaller gauge needles, administering the injection slowly, and warming or buffering the solution. Studies have shown that tap water is safe to use for irrigation, that white petrolatum ointment is as effective as antibiotic ointment in postprocedure care, and that wetting the wound as early as 12 hours after repair does not increase the risk of infection. Patient education and appropriate procedural coding are important after the repair.

  16. Bonded composite repair of composite structures

    NASA Astrophysics Data System (ADS)

    Mahler, Mary A.

    Repair and maintenance cost drives a large percentage of the lifetime cost of aircraft structures. Understanding repair issues can lead to a structure that significantly lowers the lifetime cost. Advanced composite materials, while offering the potential to increase aircraft capabilities with minimum weight, are more susceptible to repairable damage than conventional aircraft materials. Improved inspection and repair methods are required to ensure structural integrity and aircraft readiness in the existing operational environment. Many of today's innovative composite designs may result in aircraft structures that are unreasonably difficult to repair. As a first step, technical issues associated with bonded composite repair of composite structures were investigated. An extensive literature review identified many areas where real world composite repairs are being used successfully. An electronic database was developed summarizing the publications found during the literature review. The database includes publication, experimental test results and analytical results of advanced composite bonded repairs. The current analysis of repair does not account for the variations that exist in repair. To facilitate the analysis, a finite element interface was developed to provide analysts with a tool that would create complete finite element models of repaired structures efficiently and in a 3-dimensional view. The finite element models created by the developed interface were successfully correlated to test data for accuracy of the results. Parametric studies were performed using the interface to evaluate effects of repair variables. Thermal impact of repair on the repair panel is one area lacking attention in the repair literature. To understand the impact of heat and thermal gradients of the repair, an analytical investigation was performed to evaluate. the parameters affected by heat. For a solid laminate, the temperature at the adhesive bondline was investigated. The primary

  17. Nuclear Dynamics of Heterochromatin Repair.

    PubMed

    Amaral, Nuno; Ryu, Taehyun; Li, Xiao; Chiolo, Irene

    2017-02-01

    Repairing double-strand breaks (DSBs) is particularly challenging in pericentromeric heterochromatin, where the abundance of repeated sequences exacerbates the risk of ectopic recombination and chromosome rearrangements. Recent studies in Drosophila cells revealed that faithful homologous recombination (HR) repair of heterochromatic DSBs relies on the relocalization of DSBs to the nuclear periphery before Rad51 recruitment. We summarize here the exciting progress in understanding this pathway, including conserved responses in mammalian cells and surprising similarities with mechanisms in yeast that deal with DSBs in distinct sites that are difficult to repair, including other repeated sequences. We will also point out some of the most important open questions in the field and emerging evidence suggesting that deregulating these pathways might have dramatic consequences for human health.

  18. Techniques in Endovascular Aneurysm Repair

    PubMed Central

    Phade, Sachin V.; Garcia-Toca, Manuel; Kibbe, Melina R.

    2011-01-01

    Endovascular repair of infrarenal abdominal aortic aneurysms (EVARs) has revolutionized the treatment of aortic aneurysms, with over half of elective abdominal aortic aneurysm repairs performed endoluminally each year. Since the first endografts were placed two decades ago, many changes have been made in graft design, operative technique, and management of complications. This paper summarizes modern endovascular grafts, considerations in preoperative planning, and EVAR techniques. Specific areas that are addressed include endograft selection, arterial access, sheath delivery, aortic branch management, graft deployment, intravascular ultrasonography, pressure sensors, management of endoleaks and compressed limbs, and exit strategies. PMID:22121487

  19. Mountain Plains Learning Experience Guide: Automotive Repair. Course: Engine Repair.

    ERIC Educational Resources Information Center

    Schramm, C.; Osland, Walt

    One of twelve individualized courses included in an automotive repair curriculum, this course covers theory and construction, inspection diagnoses, and service and overhaul of automotive engines. The course is comprised of five units: (1) Fundamentals of Four-Cycle Engines, (2) Engine Construction, (3) Valve Train, (4) Lubricating Systems, and (5)…

  20. Final report [DNA Repair and Mutagenesis - 1999

    SciTech Connect

    Walker, Graham C.

    2001-05-30

    The meeting, titled ''DNA Repair and Mutagenesis: Mechanism, Control, and Biological Consequences'', was designed to bring together the various sub-disciplines that collectively comprise the field of DNA Repair and Mutagenesis. The keynote address was titled ''Mutability Doth Play Her Cruel Sports to Many Men's Decay: Variations on the Theme of Translesion Synthesis.'' Sessions were held on the following themes: Excision repair of DNA damage; Transcription and DNA excision repair; UmuC/DinB/Rev1/Rad30 superfamily of DNA polymerases; Cellular responses to DNA damage, checkpoints, and damage tolerance; Repair of mismatched bases, mutation; Genome-instability, and hypermutation; Repair of strand breaks; Replicational fidelity, and Late-breaking developments; Repair and mutation in challenging environments; and Defects in DNA repair: consequences for human disease and aging.

  1. Outreach Materials for the Collision Repair Campaign

    EPA Pesticide Factsheets

    The Collision Repair Campaign offers outreach materials to help collision repair shops reduce toxic air exposure. Materials include a DVD, poster, training video, and materials in Spanish (materiales del outreach en español).

  2. Laparoscopic repair of inguinal hernia in adults

    PubMed Central

    Yang, Xue-Fei

    2016-01-01

    Laparoscopic repair of inguinal hernia is mini-invasive and has confirmed effects. The procedures include intraperitoneal onlay mesh (IPOM) repair, transabdominal preperitoneal (TAPP) repair and total extraperitoneal (TEP) repair. These procedures have totally different anatomic point of view, process and technical key points from open operations. The technical details of these operations are discussed in this article, also the strategies of treatment for some special conditions. PMID:27867954

  3. Computer Equipment Repair Curriculum Guide.

    ERIC Educational Resources Information Center

    Reneau, Fred; And Others

    This guide is intended for use in a course to train students to repair computer equipment and perform related administrative and customer service tasks. Addressed in the individual units are the following topics (with selected subtopics in brackets): performing administrative functions (preparing service bills, maintaining accounts and labor…

  4. Microwave Oven Repair. Teacher Edition.

    ERIC Educational Resources Information Center

    Smreker, Eugene

    This competency-based curriculum guide for teachers addresses the skills a technician will need to service microwave ovens and to provide customer relations to help retain the customer's confidence in the product and trust in the service company that performs the repair. The guide begins with a task analysis, listing 20 cognitive tasks and 5…

  5. Anodization As A Repair Technique

    NASA Technical Reports Server (NTRS)

    Groff, Roy E.; Maloney, Robert D.; Reeser, Robert W.

    1988-01-01

    Thin, hard oxide layer added to aluminum part. Surfaces on aluminum part worn out of tolerance by no more than 0.004 in. often repaired by anodizing to build up aluminum oxide layers. Oxide layers very hard and grounded to desired final dimensions.

  6. How the Brain Repairs Stuttering

    ERIC Educational Resources Information Center

    Kell, Christian A.; Neumann, Katrin; von Kriegstein, Katharina; Posenenske, Claudia; von Gudenberg, Alexander W.; Euler, Harald; Giraud, Anne-Lise

    2009-01-01

    Stuttering is a neurodevelopmental disorder associated with left inferior frontal structural anomalies. While children often recover, stuttering may also spontaneously disappear much later after years of dysfluency. These rare cases of unassisted recovery in adulthood provide a model of optimal brain repair outside the classical windows of…

  7. Fix-It Careers: Jobs in Repair

    ERIC Educational Resources Information Center

    Torpey, Elka Maria

    2010-01-01

    From auto mechanic to HVAC technicians, many occupations require repair skills. For jobseekers with the right skills, there are many advantages to a repair career. Repair work provides millions of jobs throughout the United States. Wages are often higher than average. And in many occupations, the employment outlook is bright. Plus, most repair…

  8. Welding/brazing for Space Station repair

    NASA Technical Reports Server (NTRS)

    Dickinson, David W.; Babel, H. W.; Conaway, H. R.; Hooper, W. H.

    1990-01-01

    Viewgraphs on welding/brazing for space station repair are presented. Topics covered include: fabrication and repair candidates; debris penetration of module panel; welded repair patch; mechanical assembly of utility fluid line; space station utility systems; Soviet aerospace fabrication - an overview; and processes under consideration.

  9. Standardized Curriculum for Small Engine Repair.

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    This curriculum guide for small engine repair was developed by the state of Mississippi to standardize vocational education course titles and core contents. The objectives contained in this document are common to all small engine repair programs in the state. The guide contains objectives for small engine repair I and II courses. Units in course I…

  10. Standardized Curriculum for Automotive Body Repair.

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    Standardized curricula are provided for two courses for the secondary vocational education program in Mississippi: automotive body repair I and II. The nine units in automotive body repair I are as follows: introduction; related information; basic tool usage and safety; body and frame construction; basic sheet metal repair; preparing for…

  11. 30 CFR 57.14104 - Tire repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tire repairs. 57.14104 Section 57.14104 Mineral... Devices and Maintenance Requirements § 57.14104 Tire repairs. (a) Before a tire is removed from a vehicle for tire repair, the valve core shall be partially removed to allow for gradual deflation and...

  12. 30 CFR 56.14104 - Tire repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tire repairs. 56.14104 Section 56.14104 Mineral... Devices and Maintenance Requirements § 56.14104 Tire repairs. (a) Before a tire is removed from a vehicle for tire repair, the valve core shall be partially removed to allow for gradual deflation and...

  13. Standardized Curriculum for Shoe and Boot Repair.

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    This curriculum guide for shoe and boot repair was developed by the state of Mississippi to standardize vocational education course titles and core contents. The objectives contained in this document are common to all shoe and boot repair programs in the state. The guide contains objectives for shoe and boot repair I and II courses. Units in…

  14. Cleft palate repair and variations

    PubMed Central

    Agrawal, Karoon

    2009-01-01

    Cleft palate affects almost every function of the face except vision. Today a child born with cleft palate with or without cleft lip should not be considered as unfortunate, because surgical repair of cleft palate has reached a highly satisfactory level. However for an average cleft surgeon palatoplasty remains an enigma. The surgery differs from centre to centre and surgeon to surgeon. However there is general agreement that palatoplasty (soft palate at least) should be performed between 6-12 months of age. Basically there are three groups of palatoplasty techniques. One is for hard palate repair, second for soft palate repair and the third based on the surgical schedule. Hard palate repair techniques are Veau-Wardill-Kilner V-Y, von Langenbeck, two-flap, Aleveolar extension palatoplasty, vomer flap, raw area free palatoplasty etc. The soft palate techniques are intravelar veloplasty, double opposing Z-plasty, radical muscle dissection, primary pharyngeal flap etc. And the protocol based techniques are Schweckendiek's, Malek's, whole in one, modified schedule with palatoplasty before lip repair etc. One should also know the effect of each technique on maxillofacial growth and speech. The ideal technique of palatoplasty is the one which gives perfect speech without affecting the maxillofacial growth and hearing. The techniques are still evolving because we are yet to design an ideal one. It is always good to know all the techniques and variations so that one can choose whichever gives the best result in one's hands. A large number of techniques are available in literature, and also every surgeon incorporates his own modification to make it a variation. However there are some basic techniques, which are described in details which are used in various centres. Some of the important variations are also described. PMID:19884664

  15. Shuttle orbiter TPS flight repair kit development

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The design and application of a TPS repair kit is presented. The repair kit is designed for on orbit use by a crew member working in the manned maneuvering unit (MMU). The kit includes the necessary equipment and materials to accomplish the repair tasks which include the following: HRSI emittance coating repair, damaged tile repair, missing tile repair, and multiple tile repair. Two types of repair materials required to do the small area repair and the large area repair are described. The materials area cure in place, silicone base ablator for small damaged areas and precured ablator tile for repair of larger damaged areas is examined. The cure in place ablator is also used as an adhesive to bond the precured tiles in place. An applicator for the cure in place ablator, designed to contain a two-part silicon compound, mix the two components at correct ratio, and dispense the materials at rates compatible with mission timelines established for the EVA is described.

  16. Minimally disruptive schedule repair for MCM missions

    NASA Astrophysics Data System (ADS)

    Molineaux, Matthew; Auslander, Bryan; Moore, Philip G.; Gupta, Kalyan M.

    2015-05-01

    Mine countermeasures (MCM) missions entail planning and operations in very dynamic and uncertain operating environments, which pose considerable risk to personnel and equipment. Frequent schedule repairs are needed that consider the latest operating conditions to keep mission on target. Presently no decision support tools are available for the challenging task of MCM mission rescheduling. To address this capability gap, we have developed the CARPE system to assist operation planners. CARPE constantly monitors the operational environment for changes and recommends alternative repaired schedules in response. It includes a novel schedule repair algorithm called Case-Based Local Schedule Repair (CLOSR) that automatically repairs broken schedules while satisfying the requirement of minimal operational disruption. It uses a case-based approach to represent repair strategies and apply them to new situations. Evaluation of CLOSR on simulated MCM operations demonstrates the effectiveness of case-based strategy. Schedule repairs are generated rapidly, ensure the elimination of all mines, and achieve required levels of clearance.

  17. Automatic OPC repair flow: optimized implementation of the repair recipe

    NASA Astrophysics Data System (ADS)

    Bahnas, Mohamed; Al-Imam, Mohamed; Word, James

    2007-10-01

    Virtual manufacturing that is enabled by rapid, accurate, full-chip simulation is a main pillar in achieving successful mask tape-out in the cutting-edge low-k1 lithography. It facilitates detecting printing failures before a costly and time-consuming mask tape-out and wafer print occur. The OPC verification step role is critical at the early production phases of a new process development, since various layout patterns will be suspected that they might to fail or cause performance degradation, and in turn need to be accurately flagged to be fed back to the OPC Engineer for further learning and enhancing in the OPC recipe. At the advanced phases of the process development, there is much less probability of detecting failures but still the OPC Verification step act as the last-line-of-defense for the whole RET implemented work. In recent publication the optimum approach of responding to these detected failures was addressed, and a solution was proposed to repair these defects in an automated methodology and fully integrated and compatible with the main RET/OPC flow. In this paper the authors will present further work and optimizations of this Repair flow. An automated analysis methodology for root causes of the defects and classification of them to cover all possible causes will be discussed. This automated analysis approach will include all the learning experience of the previously highlighted causes and include any new discoveries. Next, according to the automated pre-classification of the defects, application of the appropriate approach of OPC repair (i.e. OPC knob) on each classified defect location can be easily selected, instead of applying all approaches on all locations. This will help in cutting down the runtime of the OPC repair processing and reduce the needed number of iterations to reach the status of zero defects. An output report for existing causes of defects and how the tool handled them will be generated. The report will with help further learning

  18. DNA repair capacity of zebrafish.

    PubMed

    Sussman, Raquel

    2007-08-14

    Damage to the genome is unavoidable in living creatures, because of sunlight exposure as well as environmental chemicals present in food and drinking water. There is a need to monitor and purify the drinking water; therefore, several methods of detection have been developed. A very promising model system for this purpose is the zebrafish (Danio rerio), which is endowed with special qualities for detecting external as well as internal abnormalities. Grossman and Wei's assay [Grossman L, Wei Q (1995) Clin Chem 12:1854-1863], which measures the expression level of a nonreplicating recombinant plasmid DNA containing a UV-damaged luciferase reporter gene, shows that zebrafish can repair chromosomal lesions to a much greater extent than the human population. This vertebrate model is still very promising after possible down-regulation of the DNA repair enzymes.

  19. Methods of repairing a substrate

    NASA Technical Reports Server (NTRS)

    Riedell, James A. (Inventor); Easler, Timothy E. (Inventor)

    2011-01-01

    A precursor of a ceramic adhesive suitable for use in a vacuum, thermal, and microgravity environment. The precursor of the ceramic adhesive includes a silicon-based, preceramic polymer and at least one ceramic powder selected from the group consisting of aluminum oxide, aluminum nitride, boron carbide, boron oxide, boron nitride, hafnium boride, hafnium carbide, hafnium oxide, lithium aluminate, molybdenum silicide, niobium carbide, niobium nitride, silicon boride, silicon carbide, silicon oxide, silicon nitride, tin oxide, tantalum boride, tantalum carbide, tantalum oxide, tantalum nitride, titanium boride, titanium carbide, titanium oxide, titanium nitride, yttrium oxide, zirconium boride, zirconium carbide, zirconium oxide, and zirconium silicate. Methods of forming the ceramic adhesive and of repairing a substrate in a vacuum and microgravity environment are also disclosed, as is a substrate repaired with the ceramic adhesive.

  20. Large Extremity Peripheral Nerve Repair

    DTIC Science & Technology

    2015-10-01

    regeneration using our approach with an acellular nerve allograft to be equivalent to standard autograft repair in rodent models. An ongoing large animal ...be clinically acceptable for use in the animal studies in Aim 2. The anatomy of HAM is shown pictorially in Figure 7. In vivo, the epithelial...product. Given that the large animal studies with large caliber nerves in Aim 3 will use AxoGuard we feel that the single layer SIS material is totally

  1. Large Extremity Peripheral Nerve Repair

    DTIC Science & Technology

    2015-10-01

    approach with an acellular nerve allograft to be equivalent to standard autograft repair in rodent models. An ongoing large animal validation study...the animal studies in Aim 2. The anatomy of HAM is shown pictorially in Figure 7. In vivo, the epithelial layer is in contact with the amniotic...AxoGuard and Oasis SIS products are manufactured by Cook Medical. AxoGuard is simply a multi-layered SIS product. Given that the large animal studies with

  2. Wnt Signaling and Injury Repair

    PubMed Central

    Whyte, Jemima L.; Smith, Andrew A.; Helms, Jill A.

    2012-01-01

    Wnt signaling is activated by wounding and participates in every subsequent stage of the healing process from the control of inflammation and programmed cell death, to the mobilization of stem cell reservoirs within the wound site. In this review we summarize recent data elucidating the roles that the Wnt pathway plays in the injury repair process. These data provide a foundation for potential Wnt-based therapeutic strategies aimed at stimulating tissue regeneration. PMID:22723493

  3. Which mesh for hernia repair?

    PubMed Central

    Brown, CN; Finch, JG

    2010-01-01

    INTRODUCTION The concept of using a mesh to repair hernias was introduced over 50 years ago. Mesh repair is now standard in most countries and widely accepted as superior to primary suture repair. As a result, there has been a rapid growth in the variety of meshes available and choosing the appropriate one can be difficult. This article outlines the general properties of meshes and factors to be considered when selecting one. MATERIALS AND METHODS We performed a search of the medical literature from 1950 to 1 May 2009, as indexed by Medline, using the PubMed search engine (). To capture all potentially relevant articles with the highest degree of sensitivity, the search terms were intentionally broad. We used the following terms: ‘mesh, pore size, strength, recurrence, complications, lightweight, properties’. We also hand-searched the bibliographies of relevant articles and product literature to identify additional pertinent reports. RESULTS AND CONCLUSIONS The most important properties of meshes were found to be the type of filament, tensile strength and porosity. These determine the weight of the mesh and its biocompatibility. The tensile strength required is much less than originally presumed and light-weight meshes are thought to be superior due to their increased flexibility and reduction in discomfort. Large pores are also associated with a reduced risk of infection and shrinkage. For meshes placed in the peritoneal cavity, consideration should also be given to the risk of adhesion formation. A variety of composite meshes have been promoted to address this, but none appears superior to the others. Finally, biomaterials such as acellular dermis have a place for use in infected fields but have yet to prove their worth in routine hernia repair. PMID:20501011

  4. Magnesium Repair by Cold Spray

    DTIC Science & Technology

    2008-05-01

    were conducted using microstructural analysis, hardness, bond strength, and corrosion testing. 15. SUBJECT TERMS Cold spray, magnesium, aluminum ... corrosion pitting are the primary causes for removing the components from service. In addition, any repair must be confined to nonstructural areas of...unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT The U.S. Army has experienced significant corrosion problems with magnesium alloys that are used to

  5. Structural Health Monitoring of Repairs

    DTIC Science & Technology

    2010-05-01

    monitoring, the monitoring system consists of several design elements with defined interfaces. The raw monitoring signals are generated by a sensor with...is directly connected or integrated in the structure or repair. In Figure 2.3-1, the design element 1 is showing a surface mounted sensor. The...aircraft bus system. The monitoring data from the bus system are transferred to the next design element (element 4), where an onboard processing

  6. Calcium signaling in membrane repair

    PubMed Central

    Cheng, Xiping; Zhang, Xiaoli; Yu, Lu; Xu, Haoxing

    2015-01-01

    Resealing allows cells to mend damaged membranes rapidly when plasma membrane (PM) disruptions occur. Models of PM repair mechanisms include the “lipid-patch”, “endocytic removal”, and “macro-vesicle shedding” models, all of which postulate a dependence on local increases in intracellular Ca2+ at injury sites. Multiple calcium sensors, including synaptotagmin (Syt) VII, dysferlin, and apoptosis-linked gene-2 (ALG-2), are involved in PM resealing, suggesting that Ca2+ may regulate multiple steps of the repair process. Although earlier studies focused exclusively on external Ca2+, recent studies suggest that Ca2+ release from intracellular stores may also be important for PM resealing. Hence, depending on injury size and the type of injury, multiple sources of Ca2+ may be recruited to trigger and orchestrate repair processes. In this review, we discuss the mechanisms by which the resealing process is promoted by vesicular Ca2+ channels and Ca2+ sensors that accumulate at damage sites. PMID:26519113

  7. Bond strength of repaired amalgam restorations.

    PubMed

    Rey, Rosalia; Mondragon, Eduardo; Shen, Chiayi

    2015-01-01

    This in vitro study investigated the interfacial flexural strength (FS) of amalgam repairs and the optimal combination of repair materials and mechanical retention required for a consistent and durable repair bond. Amalgam bricks were created, each with 1 end roughened to expose a fresh surface before repair. Four groups followed separate repair protocols: group 1, bonding agent with amalgam; group 2, bonding agent with composite resin; group 3, mechanical retention (slot) with amalgam; and group 4, slot with bonding agent and amalgam. Repaired specimens were stored in artificial saliva for 1, 10, 30, 120, or 360 days before being loaded to failure in a 3-point bending test. Statistical analysis showed significant changes in median FS over time in groups 2 and 4. The effect of the repair method on the FS values after each storage period was significant for most groups except the 30-day storage groups. Amalgam-amalgam repair with adequate condensation yielded the most consistent and durable bond. An amalgam bonding agent could be beneficial when firm condensation on the repair surface cannot be achieved or when tooth structure is involved. Composite resin can be a viable option for amalgam repair in an esthetically demanding region, but proper mechanical modification of the amalgam surface and selection of the proper bonding system are essential.

  8. An alternative eukaryotic DNA excision repair pathway.

    PubMed Central

    Freyer, G A; Davey, S; Ferrer, J V; Martin, A M; Beach, D; Doetsch, P W

    1995-01-01

    DNA lesions induced by UV light, cyclobutane pyrimidine dimers, and (6-4)pyrimidine pyrimidones are known to be repaired by the process of nucleotide excision repair (NER). However, in the fission yeast Schizosaccharomyces pombe, studies have demonstrated that at least two mechanisms for excising UV photo-products exist; NER and a second, previously unidentified process. Recently we reported that S. pombe contains a DNA endonuclease, SPDE, which recognizes and cleaves at a position immediately adjacent to cyclobutane pyrimidine dimers and (6-4)pyrimidine pyrimidones. Here we report that the UV-sensitive S. pombe rad12-502 mutant lacks SPDE activity. In addition, extracts prepared from the rad12-502 mutant are deficient in DNA excision repair, as demonstrated in an in vitro excision repair assay. DNA repair activity was restored to wild-type levels in extracts prepared from rad12-502 cells by the addition of partially purified SPDE to in vitro repair reaction mixtures. When the rad12-502 mutant was crossed with the NER rad13-A mutant, the resulting double mutant was much more sensitive to UV radiation than either single mutant, demonstrating that the rad12 gene product functions in a DNA repair pathway distinct from NER. These data directly link SPDE to this alternative excision repair process. We propose that the SPDE-dependent DNA repair pathway is the second DNA excision repair process present in S. pombe. PMID:7623848

  9. Laparoscopic Repair of Incidentally Found Spigelian Hernia

    PubMed Central

    Nickloes, Todd; Mancini, Greg; Solla, Julio A.

    2011-01-01

    Background and Objectives: A Spigelian hernia is a rare type of hernia that occurs through a defect in the anterior abdominal wall adjacent to the linea semilunaris. Estimation of its incidence has been reported as 0.12% of all abdominal wall hernias. Traditionally, the method of repair has been an open approach. Herein, we discuss a series of laparoscopic repairs. Methods: Case series and review of the literature. Cases: Three patients are presented. All were evaluated and taken to surgery initially for a different disease process, and all were incidentally found to have a spigelian hernia. These patients underwent laparoscopic repair of their hernias; 2 were repaired intraperitoneally and one was repaired totally extraperitoneally. Two patients initially underwent a mesh repair, while the third had an attempted primary repair. Conclusions: There is evidence that supports the use of laparoscopy for both diagnosis and repair of spigelian hernias. There are also reports of successful repairs both primarily and with mesh. In our experience with the preceding 3 patients, we found that laparoscopic repair of incidentally discovered spigelian hernias is a viable option, and we also found that implantation of mesh, when possible, resulted in satisfactory results and no recurrence. PMID:21902949

  10. Diver assisted pipeline repair manual. Volume 3

    SciTech Connect

    Not Available

    1992-12-01

    This manual is comprised of vendor supplied parts lists and information on various aspects of underwater pipeline repair. Topics include mechanical repair components, welded repair components, inspection vehicles-tools, pipeline handling systems, cleaning and coatings removal tools, bolt-stud tensioning tools, friction welding, NDT tools, handling tools, pipe anchoring components, pigging and plugging equipment, corrosion preventative coatings, trenching-burial equipment. Also listed are diving contractors, support vessel operators and a bibliography of technical publications.

  11. Spall Repair of Wet Concrete Surfaces

    DTIC Science & Technology

    1990-01-01

    ILE COPY REPAIR, EVALUATION, MAINTENANCE, AND REHABILITATION RESEARCH PROGRAM TECHNICAL REPORT REMR-CS-25 SPALL REPAIR OF WET CONCRETE SURFACES by J...of the number designating technical reports of research published under the Repair, Evaluation. Maintenance. and Rehabilitation (REMR) Research ...Program identify the problem area under which the report was prepared Problem Area Problem Area CS Concrete and Steel Structures EM Electrical and

  12. Thermal protection system repair kit program

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The feasibility and conceptual design aspects of repair materials and procedures for in orbit repair of the space shuttle orbiter TPS tiles are investigated. Material studies to investigate cure in place materials are described including catalyst and cure studies, ablation tests and evaluations, and support mixing and applicator design. The feasibility of the repair procedures, the storage of the TPS, dispensing, and cure problems are addressed.

  13. Integrated Electrical Wire Insulation Repair System

    NASA Technical Reports Server (NTRS)

    Williams, Martha; Jolley, Scott; Gibson, Tracy; Parks, Steven

    2013-01-01

    An integrated system tool will allow a technician to easily and quickly repair damaged high-performance electrical wire insulation in the field. Low-melt polyimides have been developed that can be processed into thin films that work well in the repair of damaged polyimide or fluoropolymer insulated electrical wiring. Such thin films can be used in wire insulation repairs by affixing a film of this low-melt polyimide to the damaged wire, and heating the film to effect melting, flow, and cure of the film. The resulting repair is robust, lightweight, and small in volume. The heating of this repair film is accomplished with the use of a common electrical soldering tool that has been modified with a special head or tip that can accommodate the size of wire being repaired. This repair method can furthermore be simplified for the repair technician by providing replaceable or disposable soldering tool heads that have repair film already "loaded" and ready for use. The soldering tool heating device can also be equipped with a battery power supply that will allow its use in areas where plug-in current is not available

  14. Plasma Membrane Repair in Health and Disease

    PubMed Central

    Demonbreun, Alexis R.; McNally, Elizabeth M.

    2016-01-01

    Since an intact membrane is required for normal cellular homeostasis, membrane repair is essential for cell survival. Human genetic studies, combined with the development of novel animal models and refinement of techniques to study cellular injury, have now uncovered series of repair proteins highly relevant for human health. Many of the deficient repair pathways manifest in skeletal muscle, where defective repair processes result in myopathies or other forms of muscle disease. Dysferlin is a membrane-associated protein implicated in sarcolemmal repair and also linked to other membrane functions including the maintenance of transverse tubules in muscle. MG53, annexins, and Eps15-homology domain (EHD)-containing proteins interact with dysferlin to form a membrane repair complex and similarly have roles in membrane trafficking in muscle. These molecular features of membrane repair are not unique to skeletal muscle, but rather skeletal muscle, due to its high demands, is more dependent on an efficient repair process. Phosphatidylserine and phosphatidylinositol 4, 5 bisphosphate, as well as Ca2+, are central regulators of membrane organization during repair. Given the importance of muscle health in disease and in aging, these pathways are targets to enhance muscle function and recovery from injury. PMID:26781830

  15. Current Trends in Laparoscopic Ventral Hernia Repair

    PubMed Central

    Patapis, Paul; Zavras, Nick; Tzanetis, Panagiotis; Machairas, Anastasios

    2015-01-01

    Background and Objectives: The purpose of this study was to analyze the surgical technique, postoperative complications, and possible recurrence after laparoscopic ventral hernia repair (LVHR) in comparison with open ventral hernia repair (OVHR), based on the international literature. Database: A Medline search of the current English literature was performed using the terms laparoscopic ventral hernia repair and incisional hernia repair. Conclusions: LVHR is a safe alternative to the open method, with the main advantages being minimal postoperative pain, shorter recovery, and decreased wound and mesh infections. Incidental enterotomy can be avoided by using a meticulous technique and sharp dissection to avoid thermal injury. PMID:26273186

  16. 33 CFR 127.405 - Repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... FACILITIES WATERFRONT FACILITIES HANDLING LIQUEFIED NATURAL GAS AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas Maintenance § 127.405 Repairs. The operator shall ensure that—...

  17. Repair and rehabilitation with polymer concrete

    SciTech Connect

    Kukacka, L.E.

    1988-09-01

    As a result of their fast setting characteristics and excellent mechanical and physical properties, polymer concretes (PC) are finding ever increasing useage for the repair of deteriorated portland cement concrete structures. Applications include the repair of highway pavements and bridge decks, airport runways, hydrotechnical structures, tunnels, and industrial flooring. The most commonly used resins and monomer systems for these applications are epoxies, polyesters and methylmethacrylate. Furfuryl alcohol has been used experimentally, and shows promise for use in making emergency repairs under adverse moisture or extreme temperature conditions. In the paper, repair procedures will be discussed and several case histories given. 6 refs.

  18. Transcriptomic Approaches to Neural Repair

    PubMed Central

    Antunes-Martins, Ana; Chandran, Vijayendran; Costigan, Michael; Lerch, Jessica K.; Willis, Dianna E.; Tuszynski, Mark H.

    2015-01-01

    Understanding why adult CNS neurons fail to regenerate their axons following injury remains a central challenge of neuroscience research. A more complete appreciation of the biological mechanisms shaping the injured nervous system is a crucial prerequisite for the development of robust therapies to promote neural repair. Historically, the identification of regeneration associated signaling pathways has been impeded by the limitations of available genetic and molecular tools. As we progress into an era in which the high-throughput interrogation of gene expression is commonplace and our knowledge base of interactome data is rapidly expanding, we can now begin to assemble a more comprehensive view of the complex biology governing axon regeneration. Here, we highlight current and ongoing work featuring transcriptomic approaches toward the discovery of novel molecular mechanisms that can be manipulated to promote neural repair. SIGNIFICANCE STATEMENT Transcriptional profiling is a powerful technique with broad applications in the field of neuroscience. Recent advances such as single-cell transcriptomics, CNS cell type-specific and developmental stage-specific expression libraries are rapidly enhancing the power of transcriptomics for neuroscience applications. However, extracting biologically meaningful information from large transcriptomic datasets remains a formidable challenge. This mini-symposium will highlight current work using transcriptomic approaches to identify regulatory networks in the injured nervous system. We will discuss analytical strategies for transcriptomics data, the significance of noncoding RNA networks, and the utility of multiomic data integration. Though the studies featured here specifically focus on neural repair, the approaches highlighted in this mini-symposium will be of broad interest and utility to neuroscientists working in diverse areas of the field. PMID:26468186

  19. 14 CFR 145.107 - Satellite repair stations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Satellite repair stations. 145.107 Section... Data § 145.107 Satellite repair stations. (a) A certificated repair station under the managerial control of another certificated repair station may operate as a satellite repair station with its...

  20. 24 CFR 206.47 - Property standards; repair work.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Property standards; repair work... Property standards; repair work. (a) Need for repairs. Properties must meet the applicable property... insured mortgage. (b) Assurance that repairs are made. The mortgage may be closed before the repair...

  1. Laparoscopic repair of parastomal hernia

    PubMed Central

    Yang, Xuefei; He, Kai; Hua, Rong; Shen, Qiwei

    2017-01-01

    Parastomal hernia is one of the most common long-term complications after abdominal ostomy. Surgical treatment for parastomal hernia is the only cure but a fairly difficult field because of the problems of infection, effects, complications and recurrence. Laparoscopic repair operations are good choices for Parastomal hernia because of their mini-invasive nature and confirmed effects. There are several major laparoscopic procedures for parastomal hernioplasty. The indications, technical details and complications of them will be introduced and discussed in this article. PMID:28251124

  2. 49 CFR 1242.42 - Administration, repair and maintenance, machinery repair, equipment damaged, dismantling retired...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... repair, equipment damaged, dismantling retired property, fringe benefits, other casualties and insurance, lease rentals, joint facility rents, other rents, depreciation, joint facility, repairs billed to others... PASSENGER SERVICE FOR RAILROADS 1 Operating Expenses-Equipment § 1242.42 Administration, repair...

  3. A history of the DNA repair and mutagenesis field: The discovery of base excision repair.

    PubMed

    Friedberg, Errol C

    2016-01-01

    This article reviews the early history of the discovery of an DNA repair pathway designated as base excision repair (BER), since in contrast to the enzyme-catalyzed removal of damaged bases from DNA as nucleotides [called nucleotide excision repair (NER)], BER involves the removal of damaged or inappropriate bases, such as the presence of uracil instead of thymine, from DNA as free bases.

  4. Regenerative endodontics: regeneration or repair?

    PubMed

    Simon, Stéphane R J; Tomson, Phillip L; Berdal, Ariane

    2014-04-01

    Recent advances in biotechnology and translational research have made it possible to provide treatment modalities that protect the vital pulp, allow manipulation of reactionary and reparative dentinogenesis, and, more recently, permit revascularization of an infected root canal space. These approaches are referred to as regenerative procedures. The method currently used to determine the origin of the tissue secreted during the repair/regeneration process is largely based on the identification of cellular markers (usually proteins) left by cells that were responsible for this tissue production. The presence of these proteins in conjunction with other indicators of cellular behavior (especially biomineralization) and analysis of the structure of the newly generated tissue allow conclusions to be made of how it was formed. Thus far, it has not been possible to truly establish the biological mechanism controlling tertiary dentinogenesis. This article considers current therapeutic techniques to treat the dentin-pulp complex and contextualize them in terms of reparative and regenerative processes. Although it may be considered a semantic argument rather than a biological one, the definitions of regeneration and repair are explored to clarify our position in this era of regenerative endodontics.

  5. Dynamics of DNA Mismatch Repair

    NASA Astrophysics Data System (ADS)

    Coats, Julie; Lin, Yuyen; Rasnik, Ivan

    2009-11-01

    DNA mismatch repair protects the genome from spontaneous mutations by recognizing errors, excising damage, and re-synthesizing DNA in a pathway that is highly conserved. Mismatch recognition is accomplished by the MutS family of proteins which are weak ATPases that bind specifically to damaged DNA, but the specific molecular mechanisms by which these proteins recognize damage and initiate excision are not known. Previous structural investigations have implied that protein-induced conformational changes are central to mismatch recognition. Because damage detection is a highly dynamic process in which conformational changes of the protein-DNA complexes occur on a time scale of a few seconds, it is difficult to obtain meaningful kinetic information with traditional ensemble techniques. In this work, we use single molecule fluorescence resonance energy transfer (smFRET) to study the conformational dynamics of fluorescently labeled DNA substrates in the presence of the mismatch repair protein MutS from E. coli and its human homolog MSH2/MSH6. Our studies allow us to obtain quantitative kinetic information about the rates of binding and dissociation and to determine the conformational states for each protein-DNA complex.

  6. Targeting Microtubules for Wound Repair

    PubMed Central

    Charafeddine, Rabab A.; Nosanchuk, Joshua D.; Sharp, David J.

    2016-01-01

    Significance: Fast and seamless healing is essential for both deep and chronic wounds to restore the skin and protect the body from harmful pathogens. Thus, finding new targets that can both expedite and enhance the repair process without altering the upstream signaling milieu and causing serious side effects can improve the way we treat wounds. Since cell migration is key during the different stages of wound healing, it presents an ideal process and intracellular structural machineries to target. Recent Advances and Critical Issues: The microtubule (MT) cytoskeleton is rising as an important structural and functional regulator of wound healing. MTs have been reported to play different roles in the migration of the various cell types involved in wound healing. Specific microtubule regulatory proteins (MRPs) can be targeted to alter a section or subtype of the MT cytoskeleton and boost or hinder cell motility. However, inhibiting intracellular components can be challenging in vivo, especially using unstable molecules, such as small interfering RNA. Nanoparticles can be used to protect these unstable molecules and topically deliver them to the wound. Utilizing this approach, we recently showed that fidgetin-like 2, an uncharacterized MRP, can be targeted to enhance cell migration and wound healing. Future Directions: To harness the full potential of the current MRP therapeutic targets, studies should test them with different delivery platforms, dosages, and skin models. Screening for new MT effectors that boost cell migration in vivo would also help find new targets for skin repair. PMID:27785378

  7. Evaluation of Vibratory Rollers for Bomb Damage Repair.

    DTIC Science & Technology

    1980-08-01

    Repair Base Course Bomb Damage Repair Crushed Stone Vibratory Rollers\\ Soil Compaction Unsurfaced Repairs 0. ABSTRACT (Continue on reveres aide if...3 Test Areas ....... ............. ............ 3 Vibratory Rollers............................... 3 Soils ...Roller Evaluation Tests ................. 16 Soil Preparation and Placement ................ 16 Compaction .................................... 16

  8. International congress on DNA damage and repair: Book of abstracts

    SciTech Connect

    Not Available

    1987-01-01

    This document contains the abstracts of 105 papers presented at the Congress. Topics covered include the Escherichia coli nucleotide excision repair system, DNA repair in malignant transformations, defective DNA repair, and gene regulation. (TEM)

  9. AUTOMOTIVE REPAIR SHOP, DETAIL OF MILLS COAL BOILER WITH SCREWFEED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, DETAIL OF MILLS COAL BOILER WITH SCREW-FEED COAL HOPPER ON RIGHT SIDE, WITH SCALE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  10. Lube rack of Automotive and Tractor Repair Shops with Warehousefield ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Lube rack of Automotive and Tractor Repair Shops with Warehouse-field Equipment Repair Shop Building's wall to the right, looking from the south - Kekaha Sugar Company, Automotive and Tractor Repair Shops, 8315 Kekaha Road, Kekaha, Kauai County, HI

  11. AUTOMOTIVE REPAIR SHOP, INTERIOR VIEW TO SOUTHEAST, DOORWAYS TO SHOP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, INTERIOR VIEW TO SOUTHEAST, DOORWAYS TO SHOP OFFICE AND SOUTH WING, WITH SCALE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  12. AUTOMOTIVE REPAIR SHOP, SLIDING DOOR LEADING TO BOILER ROOM ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, SLIDING DOOR LEADING TO BOILER ROOM ON SOUTH SIDE OF SOUTH WING. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  13. AUTOMOTIVE REPAIR SHOP, DETAIL OF BUILDING CORNER (MAIN WING) SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, DETAIL OF BUILDING CORNER (MAIN WING) SHOWING WOOD EAVE AND STUCCO RAKEBOARD ON GABLE END, WITH SCALE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  14. AUTOMOTIVE REPAIR SHOP, DETAIL OF FABRICATING PRESS IN EAST END ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, DETAIL OF FABRICATING PRESS IN EAST END OF MAIN WING, WITH SCALE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  15. AUTOMOTIVE REPAIR SHOP, DETAIL OF MILLS COAL BOILER WITH SCREWFEED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, DETAIL OF MILLS COAL BOILER WITH SCREW-FEED COAL HOPPER ON RIGHT SIDE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  16. AUTOMOTIVE REPAIR SHOP, DETAIL OF BUILDING CORNER (MAIN WING) SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, DETAIL OF BUILDING CORNER (MAIN WING) SHOWING WOOD EAVE AND STUCCO RAKEBOARD ON GABLE END. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  17. AUTOMOTIVE REPAIR SHOP, SLIDING DOOR LEADING TO BOILER ROOM ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, SLIDING DOOR LEADING TO BOILER ROOM ON SOUTH SIDE OF SOUTH WING, WITH SCALE. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  18. AUTOMOTIVE REPAIR SHOP, INTERIOR VIEW TO SOUTHEAST, DOORWAYS TO SHOP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    AUTOMOTIVE REPAIR SHOP, INTERIOR VIEW TO SOUTHEAST, DOORWAYS TO SHOP OFFICE AND SOUTH WING. - Cedar City Automotive Repair Shop, Automotive Repair Shop, 820 North Main Street, Cedar City, Iron County, UT

  19. 40 CFR 60.482-9 - Standards: Delay of repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... purged material resulting from immediate repair are greater than the fugitive emissions likely to result from delay of repair, and (2) When repair procedures are effected, the purged material is collected...

  20. 40 CFR 61.242-10 - Standards: Delay of repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... repair for valves will be allowed if: (1) The owner or operator demonstrates that emissions of purged... delay of repair, and (2) When repair procedures are effected, the purged material is collected...

  1. 5. EXTERIOR VIEW OF THE NORTH REPAIR BAY OF THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. EXTERIOR VIEW OF THE NORTH REPAIR BAY OF THE MOTOR REPAIR SHOP, BUILDING 104, LOOKING WEST. - Mill Valley Air Force Station, Motor Repair & Auto Hobby Shop, East Ridgecrest Boulevard, Mount Tamalpais, Mill Valley, Marin County, CA

  2. 40 CFR 65.105 - Leak repair.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pump that meets the requirements of § 65.107(e)(2) will be installed; or (C) A system that routes.... First attempt at repair for pumps includes, but is not limited to, tightening the packing gland nuts and... destroyed or recovered in a control device complying with § 65.115. (4) Delay of repair for pumps is...

  3. Robot Service and Repair. Teacher's Guide.

    ERIC Educational Resources Information Center

    Pittsburg State Univ., KS. Kansas Vocational Curriculum Dissemination Center.

    This document is a teacher's guide for teaching a course on robot service and repair. The guide is organized in four units covering the following topics: introduction to robots, power supply, robot control systems, and service and repair. Each unit contains several lesson plans on the unit topic. Lesson plans consist of objectives, tools and…

  4. Robot Service and Repair. Student Guide.

    ERIC Educational Resources Information Center

    Pittsburg State Univ., KS. Kansas Vocational Curriculum Dissemination Center.

    This document is a student guide for a course on robot service and repair. It is organized in four units covering the following topics: introduction to robots, power supply, robot control systems, and service and repair. Each unit contains several lesson plans on the unit topic. Lesson plans consist of lesson objectives, lists of teaching aids and…

  5. Human DNA repair and recombination genes

    SciTech Connect

    Thompson, L.H.; Weber, C.A.; Jones, N.J.

    1988-09-01

    Several genes involved in mammalian DNA repair pathways were identified by complementation analysis and chromosomal mapping based on hybrid cells. Eight complementation groups of rodent mutants defective in the repair of uv radiation damage are now identified. At least seven of these genes are probably essential for repair and at least six of them control the incision step. The many genes required for repair of DNA cross-linking damage show overlap with those involved in the repair of uv damage, but some of these genes appear to be unique for cross-link repair. Two genes residing on human chromosome 19 were cloned from genomic transformants using a cosmid vector, and near full-length cDNA clones of each gene were isolated and sequenced. Gene ERCC2 efficiently corrects the defect in CHO UV5, a nucleotide excision repair mutant. Gene XRCC1 normalizes repair of strand breaks and the excessive sister chromatid exchange in CHO mutant EM9. ERCC2 shows a remarkable /approximately/52% overall homology at both the amino acid and nucleotide levels with the yeast RAD3 gene. Evidence based on mutation induction frequencies suggests that ERCC2, like RAD3, might also be an essential gene for viability. 100 refs., 4 tabs.

  6. Flavonoids and DNA Repair in Prostate Cancer

    DTIC Science & Technology

    2005-12-01

    hours of naringenin treatment. The tea flavonoid EGC and apigenin from parsley did not show any DNA repair-stimulatory activity. 15. SUBJECT TERMS No...flavonoids to continue the investigations on the stimulatory effect on DNA repair: -naringenin from citrus -apigenin from parsley -epicatechin

  7. Thermal protection system flight repair kit

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A thermal protection system (TPS) flight repair kit required for use on a flight of the Space Transportation System is defined. A means of making TPS repairs in orbit by the crew via extravehicular activity is discussed. A cure in place ablator, a precured ablator (large area application), and packaging design (containers for mixing and dispensing) for the TPS are investigated.

  8. Railroad track repairs are complete at KSC

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Railroad track repairs have been completed at Kennedy Space Center. This section of track is located on KSC property, just north of the NASA Causeway in the KSC Industrial Area. The repairs were required following the minor derailment of two solid rocket booster segment cars on July 18.

  9. Self repairing composites for drone air vehicles

    NASA Astrophysics Data System (ADS)

    Dry, Carolyn

    2015-04-01

    The objective of this effort was to demonstrate the feasibility of impact-initiated delivery of repair chemicals through hollow fiber architectures embedded within graphite fiber reinforced polymer matrix composites, representative of advanced drone aircraft component material systems. Self-repairing structures through coupon and elements were demonstrated, and evaluated.

  10. 46 CFR 160.006-2 - Repairing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Repairing. 160.006-2 Section 160.006-2 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS.... No repairs, except in emergency, shall be made to an approved life preserver without advance...

  11. 30 CFR 56.6801 - Vehicle repair.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Vehicle repair. 56.6801 Section 56.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Vehicle repair. Vehicles containing explosive material and oxidizers shall not be taken into a...

  12. 30 CFR 56.6801 - Vehicle repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Vehicle repair. 56.6801 Section 56.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Vehicle repair. Vehicles containing explosive material and oxidizers shall not be taken into a...

  13. 30 CFR 56.6801 - Vehicle repair.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Vehicle repair. 56.6801 Section 56.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Vehicle repair. Vehicles containing explosive material and oxidizers shall not be taken into a...

  14. 30 CFR 56.6801 - Vehicle repair.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Vehicle repair. 56.6801 Section 56.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Vehicle repair. Vehicles containing explosive material and oxidizers shall not be taken into a...

  15. 30 CFR 57.6801 - Vehicle repair.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Vehicle repair. 57.6801 Section 57.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... and Underground § 57.6801 Vehicle repair. Vehicles containing explosive material and oxidizers...

  16. 30 CFR 57.6801 - Vehicle repair.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Vehicle repair. 57.6801 Section 57.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... and Underground § 57.6801 Vehicle repair. Vehicles containing explosive material and oxidizers...

  17. 30 CFR 57.6801 - Vehicle repair.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Vehicle repair. 57.6801 Section 57.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... and Underground § 57.6801 Vehicle repair. Vehicles containing explosive material and oxidizers...

  18. 30 CFR 57.6801 - Vehicle repair.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Vehicle repair. 57.6801 Section 57.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... and Underground § 57.6801 Vehicle repair. Vehicles containing explosive material and oxidizers...

  19. 30 CFR 57.6801 - Vehicle repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Vehicle repair. 57.6801 Section 57.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... and Underground § 57.6801 Vehicle repair. Vehicles containing explosive material and oxidizers...

  20. 30 CFR 56.6801 - Vehicle repair.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Vehicle repair. 56.6801 Section 56.6801 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Vehicle repair. Vehicles containing explosive material and oxidizers shall not be taken into a...

  1. Anatomy essentials for laparoscopic inguinal hernia repair

    PubMed Central

    Yang, Xue-Fei

    2016-01-01

    Laparoscopic inguinal hernia repair is performed more and more nowadays. The anatomy of these procedures is totally different from traditional open procedures because they are performed from different direction and in different space. The important anatomy essentials for laparoscopic inguinal hernia repair will be discussed in this article. PMID:27826575

  2. Evaluation of Rapid-Setting Concretes for Airfield Spall Repair

    DTIC Science & Technology

    1991-04-01

    repair concretes for Rapid Runway Repair (RRR). The three were a methyl methacrylate binder (Silikal RI7AF), a magnesium phosphate mortar mix (Set-45...Performance Reauirements Definition of small repair 5. The Rapid Runway Repair Program of the US Air Force (USAF) includes the activities that must be performed...scenario for wartime spall repair includes the expectation that a runway will be damaged by tens to hundreds of spalls at one time. The repair activity

  3. Repair Development for a Composite Cryotank

    NASA Technical Reports Server (NTRS)

    Cox, Sarah B.; Danley, Susan E.; Caraccio, Anne J.; Cheshire, Brian C.; Sampson, Jeffrey W.; Taylor, Brian J.

    2014-01-01

    The Composite Cryotank Technologies and Demonstration Project is working to advance the technologies for composite cryogenic propellant tanks at diameters suitable for future heavy lift vehicles and other in-space applications. The main goals of the project are to reduce weight and cost. One aspect of this project has focused on damage evaluation and repair development. Test panels have been impacted, repaired, and tested. Several repair methods were used to compare their effectiveness at restoring the integrity of the composite. Panels were evaluated by nondestructive evaluations at several points during the process to assess the damage and repair. The testing performed and the results and conclusions from the nondestructive evaluations and the destructive testing will be discussed. These results will lead to further development of inspection techniques and repair methods.

  4. Effect of acrylamide on hepatocellular DNA repair

    SciTech Connect

    Miller, M.J.; McQueen, C.A.

    1986-01-01

    Acrylamide has recently been reported to induce tumors in laboratory animals. The effect of acrylamide on unscheduled DNA synthesis using the hepatocyte primary culture (HPC)/DNA repair test was examined. Isolated hepatocytes were exposed to acrylamide and (3H)thymidine ( (3H)TdR) for 18 hr. Incorporation of (3H)TdR into DNA was determined by autoradiography. No DNA repair was observed at acrylamide concentrations up to 10(-2) M. These findings were confirmed using density gradients. Acrylamide concentrations exceeding 10(-2) M were cytotoxic to hepatocytes. Because both autoradiography and density gradients measure DNA repair as an endpoint, the ability of acrylamide to inhibit these repair processes was also determined. Acrylamide had no effect on the repair of UV-damaged DNA. These results show that acrylamide is not genotoxic in isolated hepatocytes.

  5. Laparoscopic herniorrhaphy. Transabdominal preperitoneal floor repair.

    PubMed

    Felix, E L; Michas, C A; McKnight, R L

    1994-02-01

    The purpose of this study was to evaluate the results of a laparoscopic transabdominal preperitoneal (TAPP) approach to inguinal hernia repair which dissected the entire inguinal floor and repaired the indirect, direct, and femoral areas in all patients without tension. In our series, 183 patients had 205 hernia repairs and were followed for more than 6 months. Of this group, 128 hernias were indirect, 55 direct, 22 pantaloon, 26 recurrent, and 22 bilateral. All 12 females and the first 11 males had a single-buttress repair with polypropylene mesh. The other 160 male patients had a double-buttress repair. With median follow-up of 12 months, ranging from 6 to 21 months, no recurrences were found. Patients returned to normal activity in an average of 1 week. Dissection and buttressing of the entire inguinal floor with mesh appeared to solve the problem of early recurrence first seen in laparoscopic herniorrhaphy.

  6. Mitral valve repair for ischemic mitral regurgitation.

    PubMed

    Mohebali, Jahan; Chen, Frederick Y

    2015-05-01

    Mitral valve repair for ischemic mitral valve regurgitation remains controversial. In moderate mitral regurgitation (MR), controversy exists whether revascularization alone will be adequate to restore native valve geometry or whether intervention on the valve (repair) should be performed concomitantly. When MR is severe, the need for valve intervention is not disputed. Rather, the controversy is whether repair versus replacement should be undertaken. In contrast to degenerative or myxomatous disease that directly affects leaflet integrity and morphology, ischemic FMR results from a distortion and dilation of native ventricular geometry that normally supports normal leaflet coaptation. To address this, the first and most crucial step in successful valve repair is placement of an undersized, complete remodeling annuloplasty ring to restore the annulus to its native geometry. The following article outlines the steps for repair of ischemic mitral regurgitation.

  7. Integrated structural repair of a producing FPSO

    SciTech Connect

    Johnson, P.R.; Smith, T.A.

    1997-07-01

    The state of the art in FPSO design is advancing rapidly. The long-term reliability of FPSO systems has improved as maintenance issues, have received greater emphasis in both new-builds and conversions. Despite this new emphasis, problems will still arise and repairs will still be required. Ultimately, the ability of any FPSO to stay on location and on production will depend on the scope of repairs which can be economically performed in-situ. In 1994 and 1995, Marathon Petroleum Indonesia Limited (MPIL) performed an in-situ repair on the FPSO Kakap Natuna. The scope and complexity of this work suggests there are few, if any, limits on in-situ structural repairs which can be successfully performed on a producing FPSO. The use of an integrated execution strategy for the repairs greatly reduced their cost.

  8. DNA Triplet Repeat Expansion and Mismatch Repair

    PubMed Central

    Iyer, Ravi R.; Pluciennik, Anna; Napierala, Marek; Wells, Robert D.

    2016-01-01

    DNA mismatch repair is a conserved antimutagenic pathway that maintains genomic stability through rectification of DNA replication errors and attenuation of chromosomal rearrangements. Paradoxically, mutagenic action of mismatch repair has been implicated as a cause of triplet repeat expansions that cause neurological diseases such as Huntington disease and myotonic dystrophy. This mutagenic process requires the mismatch recognition factor MutSβ and the MutLα (and/or possibly MutLγ) endonuclease, and is thought to be triggered by the transient formation of unusual DNA structures within the expanded triplet repeat element. This review summarizes the current knowledge of DNA mismatch repair involvement in triplet repeat expansion, which encompasses in vitro biochemical findings, cellular studies, and various in vivo transgenic animal model experiments. We present current mechanistic hypotheses regarding mismatch repair protein function in mediating triplet repeat expansions and discuss potential therapeutic approaches targeting the mismatch repair pathway. PMID:25580529

  9. Systems Maintenance Automated Repair Tasks (SMART)

    NASA Technical Reports Server (NTRS)

    Schuh, Joseph; Mitchell, Brent; Locklear, Louis; Belson, Martin A.; Al-Shihabi, Mary Jo Y.; King, Nadean; Norena, Elkin; Hardin, Derek

    2010-01-01

    SMART is a uniform automated discrepancy analysis and repair-authoring platform that improves technical accuracy and timely delivery of repair procedures for a given discrepancy (see figure a). SMART will minimize data errors, create uniform repair processes, and enhance the existing knowledge base of engineering repair processes. This innovation is the first tool developed that links the hardware specification requirements with the actual repair methods, sequences, and required equipment. SMART is flexibly designed to be useable by multiple engineering groups requiring decision analysis, and by any work authorization and disposition platform (see figure b). The organizational logic creates the link between specification requirements of the hardware, and specific procedures required to repair discrepancies. The first segment in the SMART process uses a decision analysis tree to define all the permutations between component/ subcomponent/discrepancy/repair on the hardware. The second segment uses a repair matrix to define what the steps and sequences are for any repair defined in the decision tree. This segment also allows for the selection of specific steps from multivariable steps. SMART will also be able to interface with outside databases and to store information from them to be inserted into the repair-procedure document. Some of the steps will be identified as optional, and would only be used based on the location and the current configuration of the hardware. The output from this analysis would be sent to a work authoring system in the form of a predefined sequence of steps containing required actions, tools, parts, materials, certifications, and specific requirements controlling quality, functional requirements, and limitations.

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

    SciTech Connect

    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.

  11. Postreplication repair in Saccharomyces cerevisiae

    SciTech Connect

    Resnick, M.A.; Boyce, J.; Cox, B.

    1981-04-01

    Postreplication events in logarithmically growing excision-defective mutants of Saccharomyces cerevisiae were examined after low doses of ultraviolet light. Pulse-labeled deoxyribonucleic acid had interruptions, and when the cells were chased, the interruptions were no longer detected. Since the loss of interruptions was not associated with an exchange of pyrimidine dimers at a detection level of 10 to 20% of the induced dimers, it was concluded that postreplication repair in excision-defective mutants does not involve molecular recombination. Pyrimidine dimers were assayed by utilizing the ultraviolet-endonuclease activity in extracts of Micrococcus luteus and newly developed alkaline sucrose gradient techniques, which yielded chromosomal-size deoxyribonucleic acid after treatment of irradiated cells.

  12. Signaling Pathways in Cartilage Repair

    PubMed Central

    Mariani, Erminia; Pulsatelli, Lia; Facchini, Andrea

    2014-01-01

    In adult healthy cartilage, chondrocytes are in a quiescent phase characterized by a fine balance between anabolic and catabolic activities. In ageing, degenerative joint diseases and traumatic injuries of cartilage, a loss of homeostatic conditions and an up-regulation of catabolic pathways occur. Since cartilage differentiation and maintenance of homeostasis are finely tuned by a complex network of signaling molecules and biophysical factors, shedding light on these mechanisms appears to be extremely relevant for both the identification of pathogenic key factors, as specific therapeutic targets, and the development of biological approaches for cartilage regeneration. This review will focus on the main signaling pathways that can activate cellular and molecular processes, regulating the functional behavior of cartilage in both physiological and pathological conditions. These networks may be relevant in the crosstalk among joint compartments and increased knowledge in this field may lead to the development of more effective strategies for inducing cartilage repair. PMID:24837833

  13. Shuttle Repair Tools Automate Vehicle Maintenance

    NASA Technical Reports Server (NTRS)

    2013-01-01

    Successfully building, flying, and maintaining the space shuttles was an immensely complex job that required a high level of detailed, precise engineering. After each shuttle landed, it entered a maintenance, repair, and overhaul (MRO) phase. Each system was thoroughly checked and tested, and worn or damaged parts replaced, before the shuttle was rolled out for its next mission. During the MRO period, workers needed to record exactly what needed replacing and why, as well as follow precise guidelines and procedures in making their repairs. That meant traceability, and with it lots of paperwork. In 2007, the number of reports generated during electrical system repairs was getting out of hand-placing among the top three systems in terms of paperwork volume. Repair specialists at Kennedy Space Center were unhappy spending so much time at a desk and so little time actually working on the shuttle. "Engineers weren't spending their time doing technical work," says Joseph Schuh, an electrical engineer at Kennedy. "Instead, they were busy with repetitive, time-consuming processes that, while important in their own right, provided a low return on time invested." The strain of such inefficiency was bad enough that slow electrical repairs jeopardized rollout on several occasions. Knowing there had to be a way to streamline operations, Kennedy asked Martin Belson, a project manager with 30 years experience as an aerospace contractor, to co-lead a team in developing software that would reduce the effort required to document shuttle repairs. The result was System Maintenance Automated Repair Tasks (SMART) software. SMART is a tool for aggregating and applying information on every aspect of repairs, from procedures and instructions to a vehicle s troubleshooting history. Drawing on that data, SMART largely automates the processes of generating repair instructions and post-repair paperwork. In the case of the space shuttle, this meant that SMART had 30 years worth of operations

  14. Diverless pipeline repair clamp: Phase 1

    SciTech Connect

    Miller, J.E.; Knott, B. )

    1991-12-01

    Offshore oil and gas developments are underway for water depths beyond which divers can function. The economic lifelines of these projects are the pipelines which will transport the products to shore. In preparation for the day when one of these pipelines will require repair because of a leak, the Pipeline Research Committee of the American Gas Association is funding research directed at developing diverless pipeline repair capabilities. Several types of damage are possible, ranging from latent weld defects on one end of the spectrum to damage resulting in parting of the pipe at the other end. This study is specifically directed toward laying the groundwork for development of a diverless pipeline repair clamp for use in repair of leaks resulting from minor pipe defects. The incentive for a clamp type repair is costs. When compared to replacing a section of pipe, either by welding or by mechanical means, the clamp type repair requires much less disturbance of the pipe, less time, fewer operations and less equipment. This report summarizes (1) capabilities of remotely operated vehicles (ROV's) and associated systems, (2) highlights areas for further research and development, (3) describes the required capabilities of the diverless repairclamp, (4) investigates some alternatives to the diverless clamp, (5) overviews the state of the art in leak repair clamps, and (6) critiques several possible generic clamp concepts.

  15. Dental materials for cleft palate repair.

    PubMed

    Sharif, Faiza; Ur Rehman, Ihtesham; Muhammad, Nawshad; MacNeil, Sheila

    2016-04-01

    Numerous bone and soft tissue grafting techniques are followed to repair cleft of lip and palate (CLP) defects. In addition to the gold standard surgical interventions involving the use of autogenous grafts, various allogenic and xenogenic graft materials are available for bone regeneration. In an attempt to discover minimally invasive and cost effective treatments for cleft repair, an exceptional growth in synthetic biomedical graft materials have occurred. This study gives an overview of the use of dental materials to repair cleft of lip and palate (CLP). The eligibility criteria for this review were case studies, clinical trials and retrospective studies on the use of various types of dental materials in surgical repair of cleft palate defects. Any data available on the surgical interventions to repair alveolar or palatal cleft, with natural or synthetic graft materials was included in this review. Those datasets with long term clinical follow-up results were referred to as particularly relevant. The results provide encouraging evidence in favor of dental and other related biomedical materials to fill the gaps in clefts of lip and palate. The review presents the various bones and soft tissue replacement strategies currently used, tested or explored for the repair of cleft defects. There was little available data on the use of synthetic materials in cleft repair which was a limitation of this study. In conclusion although clinical trials on the use of synthetic materials are currently underway the uses of autologous implants are the preferred treatment methods to date.

  16. 'Relax and Repair' to restrain aging.

    PubMed

    Krishnan, Vaidehi; Liu, Baohua; Zhou, Zhongjun

    2011-10-01

    The maintenance of genomic integrity requires the precise identification and repair of DNA damage. Since DNA is packaged and condensed into higher order chromatin, the events associated with DNA damage recognition and repair are orchestrated within the layers of chromatin. Very similar to transcription, during DNA repair, chromatin remodelling events and histone modifications act in concert to 'open' and relax chromatin structure so that repair proteins can gain access to DNA damage sites. One such histone mark critical for maintaining chromatin structure is acetylated lysine 16 of histone H4 (AcH4K16), a modification that can disrupt higher order chromatin organization and convert it into a more 'relaxed' configuration. We have recently shown that impaired H4K16 acetylation delays the accumulation of repair proteins to double strand break (DSB) sites which results in defective genome maintenance and accelerated aging in a laminopathy-based premature aging mouse model. These results support the idea that epigenetic factors may directly contribute to genomic instability and aging by regulating the efficiency of DSB repair. In this article, the interplay between epigenetic misregulation, defective DNA repair and aging is discussed.

  17. Magnetic Resonance Imaging of Cartilage Repair

    PubMed Central

    Trattnig, Siegfried; Winalski, Carl S.; Marlovits, Stephan; Jurvelin, Jukka S.; Welsch, Goetz H.; Potter, Hollis G.

    2011-01-01

    Articular cartilage lesions are a common pathology of the knee joint, and many patients may benefit from cartilage repair surgeries that offer the chance to avoid the development of osteoarthritis or delay its progression. Cartilage repair surgery, no matter the technique, requires a noninvasive, standardized, and high-quality longitudinal method to assess the structure of the repair tissue. This goal is best fulfilled by magnetic resonance imaging (MRI). The present article provides an overview of the current state of the art of MRI of cartilage repair. In the first 2 sections, preclinical and clinical MRI of cartilage repair tissue are described with a focus on morphological depiction of cartilage and the use of functional (biochemical) MR methodologies for the visualization of the ultrastructure of cartilage repair. In the third section, a short overview is provided on the regulatory issues of the United States Food and Drug Administration (FDA) and the European Medicines Agency (EMEA) regarding MR follow-up studies of patients after cartilage repair surgeries. PMID:26069565

  18. Biological Augmentation of Rotator Cuff Tendon Repair

    PubMed Central

    Kovacevic, David

    2008-01-01

    A histologically normal insertion site does not regenerate following rotator cuff tendon-to-bone repair, which is likely due to abnormal or insufficient gene expression and/or cell differentiation at the repair site. Techniques to manipulate the biologic events following tendon repair may improve healing. We used a sheep infraspinatus repair model to evaluate the effect of osteoinductive growth factors and BMP-12 on tendon-to-bone healing. Magnetic resonance imaging and histology showed increased formation of new bone and fibrocartilage at the healing tendon attachment site in the treated animals, and biomechanical testing showed improved load-to-failure. Other techniques with potential to augment repair site biology include use of platelets isolated from autologous blood to deliver growth factors to a tendon repair site. Modalities that improve local vascularity, such as pulsed ultrasound, have the potential to augment rotator cuff healing. Important information about the biology of tendon healing can also be gained from studies of substances that inhibit healing, such as nicotine and antiinflammatory medications. Future approaches may include the use of stem cells and transcription factors to induce formation of the native tendon-bone insertion site after rotator cuff repair surgery. PMID:18264850

  19. DNA excision repair in permeable human fibroblasts

    SciTech Connect

    Kaufmann, W.K.; Bodell, W.J.; Cleaver, J.E.

    1983-01-01

    U.v. irradiation of confluent human fibroblasts activated DNA repair, aspects of which were characterized in the cells after they were permeabilized. Incubation of intact cells for 20 min between irradiation and harvesting was necessary to obtain a maximum rate of reparative DNA synthesis. Cells harvested immediately after irradiation before repair was initiated displayed only a small stimulation of DNA synthesis, indicating that permeable cells have a reduced capacity to recognize pyrimidine dimers and activate repair. The distribution of sizes of DNA strands labeled during 10 min of reparative DNA synthesis resembled that of parental DNA. However, during a 60-min incubation of permeable cells at 37 degrees C, parental DNA and DNA labeled by reparative DNA synthesis were both cleaved to smaller sizes. Cleavage also occurred in unirradiated cells, indicating that endogenous nuclease was active during incubation. Repair patches synthesized in permeable cells displayed increased sensitivity to digestion by micrococcal nuclease. However, the change in sensitivity during a chase with unlabeled DNA precursors was small, suggesting that reassembly of nucleosome structure at sites of repair was impaired. To examine whether this deficiency was due to a preponderance of incomplete or unligated repair patches, 3H-labeled (repaired) DNA was purified, then digested with exonuclease III and nuclease S1 to probe for free 3' ends and single-stranded regions. About 85% of the (3H)DNA synthesized during a 10-min pulse resisted digestion, suggesting that a major fraction of the repair patches that were filled were also ligated. U.v. light-activated DNA synthesis in permeable cells, therefore, appears to represent the continuation of reparative gap-filling at sites of excision repair activated within intact cells. Gap-filling and ligation were comparatively efficient processes in permeable cells.

  20. Membrane fusion in muscle development and repair

    PubMed Central

    Demonbreun, Alexis R.; Biersmith, Bridget H.

    2015-01-01

    Mature skeletal muscle forms from the fusion of skeletal muscle precursor cells, myoblasts. Myoblasts fuse to other myoblasts to generate multinucleate myotubes during myogenesis, and myoblasts also fuse to other myotubes during muscle growth and repair. Proteins within myoblasts and myotubes regulate complex processes such as elongation, migration, cell adherence, cytoskeletal reorganization, membrane coalescence, and ultimately fusion. Recent studies have identified cell surface proteins, intracellular proteins, and extracellular signaling molecules required for the proper fusion of muscle. Many proteins that actively participate in myoblast fusion also coordinate membrane repair. Here we will review mammalian membrane fusion with specific attention to proteins that mediate myoblast fusion and muscle repair. PMID:26537430

  1. Colocutaneous Fistula after Open Inguinal Hernia Repair

    PubMed Central

    Kallis, Panayiotis; Koronakis, Nikolaos; Hadjicostas, Panayiotis

    2016-01-01

    The plug-and-patch technique is frequently used for the open repair of inguinal hernias; however, serious complications may arise on rare occasions. We present the case of a 69-year-old patient who presented with a colocutaneous fistula with the sigmoid colon 9 years after the repair of a left sliding inguinal hernia with the plug-and-patch technique. The patient underwent sigmoidectomy and excision of the fistulous track. He was discharged on postoperative day 5 and had an uneventful recovery. Although such complications are reported rarely, the surgeon must be aware of them when deciding upon the method of hernia repair. PMID:27738544

  2. Weld Repair of Thin Aluminum Sheet

    NASA Technical Reports Server (NTRS)

    Beuyukian, C. S.; Mitchell, M. J.

    1986-01-01

    Weld repairing of thin aluminum sheets now possible, using niobium shield and copper heat sinks. Refractory niobium shield protects aluminum adjacent to hole, while copper heat sinks help conduct heat away from repair site. Technique limits tungsten/inert-gas (TIG) welding bombardment zone to melt area, leaving surrounding areas around weld unaffected. Used successfully to repair aluminum cold plates on Space Shuttle, Commercial applications, especially in sealing fractures, dents, and holes in thin aluminum face sheets or clad brazing sheet in cold plates, heat exchangers, coolers, and Solar panels. While particularly suited to thin aluminum sheet, this process also used in thicker aluminum material to prevent surface damage near weld area.

  3. Method of repairing discontinuity in fiberglass structures

    NASA Technical Reports Server (NTRS)

    Gelb, L. L.; Helbert, W. B., Jr.; Enie, R. B.; Mulliken, R. F. (Inventor)

    1974-01-01

    Damaged fiberglass structures are repaired by substantially filling the irregular surfaced damaged area with a liquid, self-curing resin, preferably an epoxy resin mixed with chopped fiberglass, and then applying to the resin surface the first of several woven fiberglass swatches which has stitching in a zig-zag pattern parallel to each of its edges and a fringe of warp and fill glass fibers about the edges outward of the stitching. The method is especially applicable to repair of fiberglass rocket engine casings and is particularly advantageous since it restores the repaired fiberglass structure to substantially its original strength without any significant changes in the geometry or mass of the structure.

  4. Repair of Electronics for Long Duration Spaceflight

    NASA Technical Reports Server (NTRS)

    Pettegrew, Richard D.; Easton, John; Struk, Peter

    2007-01-01

    To reduce mission risk, long duration spaceflight and exploration activities will require greater degrees of self-sufficiency with regards to repair capability than have ever been employed before in space exploration. The current repair paradigm of replacing Orbital Replacement Units (ORUs) of malfunctioning avionics and electronic hardware will be impractical, since carrying all of the spares that could possibly be needed for a long duration mission would require upmass and volume at unprecedented and unacceptable levels. A strategy of component-level repair for electronics, however, could significantly reduce the mass and volume necessary for spares and enhance mission safety via a generic contingency capability. This approach is already used to varying degrees by the U.S. Navy, where vessels at sea experience some similar constraints such as the need for self sufficiency for moderately long time periods, and restrictions on volume of repair spares and infrastructure. The concept of conducting component-level repairs of electronics in spacecraft requires the development of design guidelines for future avionics (to enable repair), development of diagnostic techniques to allow an astronaut to pinpoint the faulty component aboard a vastly complex vehicle, and development of tools and methodologies for dealing with the physical processes of replacing the component. This physical process includes tasks such as conformal coating removal and replacement, component removal, replacement, and alignment--all in the difficulty of a reduced gravity environment. Further, the gravitational effects on the soldering process must be characterized and accounted for to ensure reliability of the newly repaired components. The Component-Level Electronics-Assembly Repair (CLEAR) project under the NASA Supportability program was established to develop and demonstrate the practicality of this repair approach. CLEAR involves collaborative efforts between NASA s Glenn Research Center

  5. Revisiting a runner cavitation repair job

    SciTech Connect

    Witman, J.K.

    1996-05-01

    This article reviews the efforts to repair turbine runner cavitation damage. The particular runner was originally repaired in 1990 with the application of a layer of beaded epoxy to areas of severe cavitation on the suction side of the blades on the upper runner. A year later, the runner was inspected, with no damage to the epoxy. In June of 1994, the runner was again inspected, and this and the most recent inspection shows that the epoxy coating is holding up well. The last inspection did show the beginnings on some erosion of the repair material. Based on this long-term series of inspections, maintenance recommendations are set forth.

  6. DNA Repair Pathways in Trypanosomatids: from DNA Repair to Drug Resistance

    PubMed Central

    Genois, Marie-Michelle; Paquet, Eric R.; Laffitte, Marie-Claude N.; Maity, Ranjan; Rodrigue, Amélie

    2014-01-01

    SUMMARY All living organisms are continuously faced with endogenous or exogenous stress conditions affecting genome stability. DNA repair pathways act as a defense mechanism, which is essential to maintain DNA integrity. There is much to learn about the regulation and functions of these mechanisms, not only in human cells but also equally in divergent organisms. In trypanosomatids, DNA repair pathways protect the genome against mutations but also act as an adaptive mechanism to promote drug resistance. In this review, we scrutinize the molecular mechanisms and DNA repair pathways which are conserved in trypanosomatids. The recent advances made by the genome consortiums reveal the complete genomic sequences of several pathogens. Therefore, using bioinformatics and genomic sequences, we analyze the conservation of DNA repair proteins and their key protein motifs in trypanosomatids. We thus present a comprehensive view of DNA repair processes in trypanosomatids at the crossroads of DNA repair and drug resistance. PMID:24600040

  7. Surgical Repair of Retrograde Type A Aortic Dissection after Thoracic Endovascular Aortic Repair

    PubMed Central

    Kim, Chang-Young; Kim, Yeon Soo; Ryoo, Ji Yoon

    2014-01-01

    It is expected that the stent graft will become an alternative method for treating aortic diseases or reducing the extent of surgery; therefore, thoracic endovascular aortic repair has widened its indications. However, it can have rare but serious complications such as paraplegia and retrograde type A aortic dissection. Here, we report a surgical repair of retrograde type A aortic dissection that was performed after thoracic endovascular aortic repair. PMID:24570865

  8. Small Engines Care, Operation, Maintenance and Repair. Volume II.

    ERIC Educational Resources Information Center

    Turner, J. Howard

    Developed by teacher educators and agricultural engineers, this teacher and student reference is for use in a course in small engine operation and maintenance. Content includes: (1) Principles of Good Workmanship, (2) Repairing Starters, (3) Maintaining and Repairing Ignition Systems, (4) Repairing Fuel Systems, (5) Repairing Governors, (6)…

  9. 46 CFR 59.15-1 - Furnace repairs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Furnace repairs. 59.15-1 Section 59.15-1 Shipping COAST... VESSELS AND APPURTENANCES Miscellaneous Boiler Repairs § 59.15-1 Furnace repairs. (a) Where corrugated or plain furnaces or flues are distorted by 11/2 inches or more, they shall be repaired by either of...

  10. 46 CFR 59.15-1 - Furnace repairs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Furnace repairs. 59.15-1 Section 59.15-1 Shipping COAST... VESSELS AND APPURTENANCES Miscellaneous Boiler Repairs § 59.15-1 Furnace repairs. (a) Where corrugated or plain furnaces or flues are distorted by 11/2 inches or more, they shall be repaired by either of...

  11. 46 CFR 59.15-1 - Furnace repairs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Furnace repairs. 59.15-1 Section 59.15-1 Shipping COAST... VESSELS AND APPURTENANCES Miscellaneous Boiler Repairs § 59.15-1 Furnace repairs. (a) Where corrugated or plain furnaces or flues are distorted by 11/2 inches or more, they shall be repaired by either of...

  12. 46 CFR 59.15-1 - Furnace repairs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Furnace repairs. 59.15-1 Section 59.15-1 Shipping COAST... VESSELS AND APPURTENANCES Miscellaneous Boiler Repairs § 59.15-1 Furnace repairs. (a) Where corrugated or plain furnaces or flues are distorted by 11/2 inches or more, they shall be repaired by either of...

  13. 46 CFR 59.15-1 - Furnace repairs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Furnace repairs. 59.15-1 Section 59.15-1 Shipping COAST... VESSELS AND APPURTENANCES Miscellaneous Boiler Repairs § 59.15-1 Furnace repairs. (a) Where corrugated or plain furnaces or flues are distorted by 11/2 inches or more, they shall be repaired by either of...

  14. 49 CFR 192.309 - Repair of steel pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Repair of steel pipe. 192.309 Section 192.309... Lines and Mains § 192.309 Repair of steel pipe. (a) Each imperfection or damage that impairs the serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding,...

  15. 49 CFR 192.309 - Repair of steel pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Repair of steel pipe. 192.309 Section 192.309... Lines and Mains § 192.309 Repair of steel pipe. (a) Each imperfection or damage that impairs the serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding,...

  16. 49 CFR 192.309 - Repair of steel pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Repair of steel pipe. 192.309 Section 192.309... Lines and Mains § 192.309 Repair of steel pipe. (a) Each imperfection or damage that impairs the serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding,...

  17. 49 CFR 192.309 - Repair of steel pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Repair of steel pipe. 192.309 Section 192.309... Lines and Mains § 192.309 Repair of steel pipe. (a) Each imperfection or damage that impairs the serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding,...

  18. 49 CFR 192.309 - Repair of steel pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Repair of steel pipe. 192.309 Section 192.309... Lines and Mains § 192.309 Repair of steel pipe. (a) Each imperfection or damage that impairs the serviceability of a length of steel pipe must be repaired or removed. If a repair is made by grinding,...

  19. 48 CFR 1371.118 - Changes-ship repair.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Changes-ship repair. 1371... SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause 1352.271-87, Changes—Ship Repair, in all solicitations...

  20. 48 CFR 1371.118 - Changes-ship repair.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Changes-ship repair. 1371... SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause 1352.271-87, Changes—Ship Repair, in all solicitations...

  1. 48 CFR 1371.118 - Changes-ship repair.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Changes-ship repair. 1371... SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause 1352.271-87, Changes—Ship Repair, in all solicitations...

  2. 48 CFR 1371.118 - Changes-ship repair.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Changes-ship repair. 1371... SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause 1352.271-87, Changes—Ship Repair, in all solicitations...

  3. 48 CFR 1371.118 - Changes-ship repair.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Changes-ship repair. 1371... SUPPLEMENTAL REGULATIONS ACQUISITIONS INVOLVING SHIP CONSTRUCTION AND SHIP REPAIR Provisions and Clauses 1371.118 Changes—ship repair. Insert clause 1352.271-87, Changes—Ship Repair, in all solicitations...

  4. 21 CFR 870.1350 - Catheter balloon repair kit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Catheter balloon repair kit. 870.1350 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1350 Catheter balloon repair kit. (a) Identification. A catheter balloon repair kit is a device used to repair or replace...

  5. 21 CFR 870.1350 - Catheter balloon repair kit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Catheter balloon repair kit. 870.1350 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1350 Catheter balloon repair kit. (a) Identification. A catheter balloon repair kit is a device used to repair or replace...

  6. 21 CFR 870.1350 - Catheter balloon repair kit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Catheter balloon repair kit. 870.1350 Section 870...) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Diagnostic Devices § 870.1350 Catheter balloon repair kit. (a) Identification. A catheter balloon repair kit is a device used to repair or replace...

  7. 48 CFR 252.247-7025 - Reflagging or repair work.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Reflagging or repair work... of Provisions And Clauses 252.247-7025 Reflagging or repair work. As prescribed in 247.574(d), use the following clause: Reflagging or Repair Work (JUN 2005) (a) Definition. Reflagging or repair...

  8. 49 CFR 396.3 - Inspection, repair, and maintenance.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Inspection, repair, and maintenance. 396.3 Section..., REPAIR, AND MAINTENANCE § 396.3 Inspection, repair, and maintenance. (a) General. Every motor carrier and... and maintenance operations to be performed; (3) A record of inspection, repairs, and...

  9. Anesthesia For In Utero Repair of Myelomeningocele

    PubMed Central

    Ferschl, Marla; Ball, Robert; Lee, Hanmin; Rollins, Mark D.

    2013-01-01

    Recently published results suggest that prenatal repair of fetal myelomeningocele is a potentially preferable alternative when compared to postnatal repair. In this article, the pathology of myelomeningocele, unique physiologic considerations, perioperative anesthetic management, and ethical considerations of open fetal surgery for prenatal myelomeningocele repair are discussed. Open fetal surgeries have many unique anesthetic issues such as inducing profound uterine relaxation, vigilance for maternal or fetal blood loss, fetal monitoring, and possible fetal resuscitation. Postoperative management, including the requirement for postoperative tocolysis and maternal analgesia are also reviewed. The success of intrauterine myelomeningocele repair relies on a well-coordinated multidisciplinary approach. Fetal surgery is an important topic for anesthesiologists to understand, as the number of fetal procedures is likely to increase as new fetal treatment centers are opened across the United States. PMID:23508219

  10. Highway Repair: A New Silicosis Threat

    PubMed Central

    Valiante, David J.; Schill, Donald P.; Rosenman, Kenneth D.; Socie, Edward

    2004-01-01

    Objectives. We describe an emerging public health concern regarding silicosis in the fast-growing highway repair industry. Methods. We examined highway construction trends, silicosis surveillance case data, and environmental exposure data to evaluate the risk of silicosis among highway repair workers. We reviewed silicosis case data from the construction industry in 3 states that have silicosis registries, and we conducted environmental monitoring for silica at highway repair work sites. Results. Our findings indicate that a large population of highway workers is at risk of developing silicosis from exposure to crystalline silica. Conclusions. Exposure control methods, medical screenings, protective health standards, and safety-related contract language are necessary for preventing future occupational disease problems among highway repair workers. PMID:15117715

  11. Integrated tools for teleoperated satellite repair

    NASA Technical Reports Server (NTRS)

    Das, H.; Fiorini, P.

    1993-01-01

    Tools and tool handling techniques designed for demonstrating the use of the Advanced Teleoperation System at JPL in satellite repair operations are described in this paper. Our model for the repair demonstration is the Main Electronics Box (MEB) replacement on the Solar Maximum Satellite Repair (SMSR) procedure developed by NASA and successfully performed by the crew of Space Shuttle STS-13 in 1984. A summary of the repair procedure consists of uncovering thermal protection blankets on the satellite, removing screws from the MEB panel, opening the panel and clamping it in place, then removing electrical connectors from their sockets, cutting cords that hold electrical cables to the MEB panel, replacing the panel, and finally reversing the previous procedures. Methods for handling tools used in our SMSR procedure, along with details of the tool designs are discussed in this paper.

  12. 40 CFR 63.1024 - Leak repair.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... detected. First attempt at repair for pumps includes, but is not limited to, tightening the packing gland... the bonnet bolts, and/or tightening the packing gland nuts, and/or injecting lubricant into...

  13. 40 CFR 65.105 - Leak repair.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... First attempt at repair for pumps includes, but is not limited to, tightening the packing gland nuts and... bonnet bolts, and/or tightening the packing gland nuts, and/or injecting lubricant into the...

  14. 40 CFR 63.1024 - Leak repair.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... detected. First attempt at repair for pumps includes, but is not limited to, tightening the packing gland... the bonnet bolts, and/or tightening the packing gland nuts, and/or injecting lubricant into...

  15. 40 CFR 63.1024 - Leak repair.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... detected. First attempt at repair for pumps includes, but is not limited to, tightening the packing gland... the bonnet bolts, and/or tightening the packing gland nuts, and/or injecting lubricant into...

  16. 40 CFR 65.105 - Leak repair.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    .... First attempt at repair for pumps includes, but is not limited to, tightening the packing gland nuts and... bonnet bolts, and/or tightening the packing gland nuts, and/or injecting lubricant into the...

  17. Abdominal aortic aneurysm repair - open - discharge

    MedlinePlus

    ... aortic aneurysm repair - open Aortic angiography Chest MRI Hardening of the ... Center-Shreveport, Shreveport, LA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla ...

  18. Bilateral inguinal hernias: simultaneous or sequential repair?

    PubMed Central

    Stott, M. A.; Sutton, R.; Royle, G. T.

    1988-01-01

    Two hundred and forty four patients underwent either simultaneous bilateral inguinal hernia repair (n = 122) or unilateral inguinal hernia (n = 122) repair at a general hospital between January 1971 and December 1981. The two groups of patients were matched for age and sex. Both groups had a similar overall incidence of post-operative complications and in both groups the duration of post-operative stay and duration of operating time were similar. Chest infections developed in 12 patients after bilateral repair and in 3 patients after unilateral repair (P less than 0.02). All patients were assessed prospectively from 4 to 15 years after operation, when no significant difference in the number of recurrent hernias was found. Our results suggest that simultaneous bilateral inguinal herniorrhaphy is economical in terms of both operating time and duration of hospital stay, and that this economy is not bought at a cost of increased short term morbidity or long-term recurrence rate. PMID:3200778

  19. A repair of a charging belt

    SciTech Connect

    Jones, N.L.

    1989-01-01

    Accelerator charging belts are expensive, and sometimes delicate items. A means of repair of the rubber coating has been found that, when applied properly, should give extended lifetime to these items at minimal cost. 3 refs.

  20. Light-Curing Adhesive Repair Tapes

    NASA Technical Reports Server (NTRS)

    Allred, Ronald; Haight, Andrea Hoyt

    2009-01-01

    Adhesive tapes, the adhesive resins of which can be cured (and thereby rigidized) by exposure to ultraviolet and/or visible light, are being developed as repair patch materials. The tapes, including their resin components, consist entirely of solid, low-outgassing, nonhazardous or minimally hazardous materials. They can be used in air or in vacuum and can be cured rapidly, even at temperatures as low as -20 C. Although these tapes were originally intended for use in repairing structures in outer space, they can also be used on Earth for quickly repairing a wide variety of structures. They can be expected to be especially useful in situations in which it is necessary to rigidize tapes after wrapping them around or pressing them onto the parts to be repaired.

  1. DNA repair genes in the Megavirales pangenome.

    PubMed

    Blanc-Mathieu, Romain; Ogata, Hiroyuki

    2016-06-01

    The order 'Megavirales' represents a group of eukaryotic viruses with a large genome encoding a few hundred up to two thousand five hundred genes. Several members of Megavirales possess genes involved in major DNA repair pathways. Some of these genes were likely inherited from an ancient virus world and some others were derived from the genomes of their hosts. Here we examine molecular phylogenies of key DNA repair enzymes in light of recent hypotheses on the origin of Megavirales, and propose that the last common ancestors of the individual families of the order Megavirales already possessed DNA repair functions to achieve and maintain a moderately large genome and that this repair capacity gradually increased, in a family-dependent manner, during their recent evolution.

  2. Cleft lip and palate repair - discharge

    MedlinePlus

    ... lip and palate Cleft lip and palate repair Review Date 5/9/2016 Updated by: David A. ... and reconstructive plastic surgery, Palm Beach Gardens, FL. Review provided by VeriMed Healthcare Network. Also reviewed by ...

  3. Double strand break (DSB) repair in heterochromatin and heterochromatin proteins in DSB repair.

    PubMed

    Lemaître, Charlène; Soutoglou, Evi

    2014-07-01

    Chromosomal translocations are a hallmark of cancer cells and they represent a major cause of tumorigenesis. To avoid chromosomal translocations, faithful repair of DNA double strand breaks (DSBs) has to be ensured in the context of high ordered chromatin structure. However, chromatin compaction is proposed to represent a barrier for DSB repair. Here we review the different mechanisms cells use to alleviate the heterochromatic barrier for DNA repair. At the same time, we discuss the activating role of heterochromatin-associated proteins in this process, therefore proposing that chromatin structure, more than being a simple barrier, is a key modulator of DNA repair.

  4. Posterior repair and sexual function

    PubMed Central

    Komesu, Yuko M.; Rogers, Rebecca G.; Kammerer-Doak, Dorothy N.; Barber, Matthew D.; Olsen, Ambre L.

    2011-01-01

    OBJECTIVE The purpose of this study was to determine the effect of posterior repair (PR) on sexual function in patients who have undergone incontinence and/or pelvic reconstructive surgery. STUDY DESIGN A cohort study of women who underwent incontinence and/or prolapse surgery was performed. Participants completed the pelvic organ prolapse urinary incontinence sexual questionnaire (PISQ) before and after the operation. PISQ scores were compared between women who underwent PR and women who did not. RESULTS Of 73 study participants, 30 women underwent PR; 43 women did not (no PR). Although there was no difference in dyspareunia between groups pre-op, dyspareunia prevalence post-op was significantly lower in the no PR group. Preoperative PISQ scores were similar between groups. After the operation, both groups significantly improved their PISQ scores, without a difference between groups. CONCLUSION Although the incidence of dyspareunia differed between PR and no PR groups, overall improvement in sexual function was reflected in improved total PISQ scores that occurred irrespective of PR performance. PMID:17618777

  5. Biomaterials for orbital fractures repair

    PubMed Central

    Totir, M; Ciuluvica, R; Dinu, I; Careba, I; Gradinaru, S

    2015-01-01

    The unique and complex anatomy of the orbit requires significant contouring of the implants to restore the proper anatomy. Fractures of the orbital region have an incidence of 10-25% from the total facial fractures and the most common age group was the third decade of life. The majority of cases required reconstruction of the orbital floor to support the globe position and restore the shape of the orbit. The reason for this was that the bony walls were comminuted and/ or bone fragments were missing. Therefore, the reconstruction of the missing bone was important rather than reducing the bone fragments. This could be accomplished by using various materials. There is hardly any anatomic region in the human body that is so controversial in terms of appropriate material used for fracture repair: non resorbable versus resorbable, autogenous/ allogeneic/ xenogenous versus alloplastic material, non-prebent versus preformed (anatomical) plates, standard versus custom-made plates, nonporous versus porous material, non-coated versus coated plates. Thus, the importance of the material used for reconstruction becomes more challenging for the ophthalmologist and the oral and maxillofacial surgeon. PMID:25914737

  6. Vesicocutaneous fistula after sliding hernia repair

    PubMed Central

    Mittal, Varun; Kapoor, Rakesh; Sureka, Sanjoy

    2016-01-01

    Sliding inguinal hernias are usually direct inguinal hernias containing various abdominal viscera. The incidence of bladder forming a part of an inguinal hernia, called as “scrotal cystocele,” is 1–4%. The risk of bladder injury is as high as 12% when repairing this type of hernia. This case report emphasizes this aspect in a 65-year-old man who presented with urinary leak through the scrotal wound following right inguinal hernia repair. PMID:26941501

  7. Repair of furocoumarin adducts in mammalian cells

    SciTech Connect

    Zolan, M.E.; Smith, C.A.; Hanawalt, P.C.

    1984-12-01

    DNA repair was studied in cultured mammalian cells treated with the furocoumarins 8-methoxypsoralen (8-MOP), aminomethyl trioxsalen, or angelicin and irradiated with near UV light. The amount of DNA cross-linked by 8-MOP in normal human cells decreased by about one-half in 24 hours after treatment; no decrease was observed in xeroderma pigmentosum cells, group A. At present, it is not known to what extent this decrease represents complete repair events at the sites of cross-links. Furocoumarin adducts elicited excision repair in normal human and monkey cells but not in xeroderma pigmentosum group A cells. This excision repair resembled in several aspects that elicited by pyrimidine dimers, formed in DNA by irradiation with 254-nm UV light; however, it appeared that for at least 8-MOP and aminomethyl trioxsalen, removal of adducts was not as efficient as was the removal of pyrimidine dimers. A comparison was also made of repair in the 172-base-pair repetitive alpha-DNA component of monkey cells to repair in the bulk of the genome. Although repair elicited by pyrimidine dimers in alpha-DNA was the same as in the bulk DNA, that following treatment of cells with either aminomethyl trioxsalen or angelicin and near UV was markedly deficient in alpha-DNA. This deficiency reflected the removal of fewer adducts from alpha-DNA after the same initial adduct frequencies. These results could mean that each furocoumarin may produce several structurally distinct adducts to DNA in cells and that the capacity of cellular repair systems to remove these various adducts may vary greatly.

  8. Fletcher Explains Methods to Repair Skylab I

    NASA Technical Reports Server (NTRS)

    1973-01-01

    On May 23, 1973, Dr. James Fletcher Administrator for NASA, appeared before the United States Senate Committee on Aeronautical and Space Sciences. Dr. Fletcher explained to the committee what methods would be attempted to repair the damaged Skylab I. He stated that if the planned repairs were successful, that it would be possible to accomplish most of the activities scheduled for the two subsequent Skylab missions, each lasting 56 days.

  9. DNA repair variants and breast cancer risk.

    PubMed

    Grundy, Anne; Richardson, Harriet; Schuetz, Johanna M; Burstyn, Igor; Spinelli, John J; Brooks-Wilson, Angela; Aronson, Kristan J

    2016-05-01

    A functional DNA repair system has been identified as important in the prevention of tumour development. Previous studies have hypothesized that common polymorphisms in DNA repair genes could play a role in breast cancer risk and also identified the potential for interactions between these polymorphisms and established breast cancer risk factors such as physical activity. Associations with breast cancer risk for 99 single nucleotide polymorphisms (SNPs) from genes in ten DNA repair pathways were examined in a case-control study including both Europeans (644 cases, 809 controls) and East Asians (299 cases, 160 controls). Odds ratios in both additive and dominant genetic models were calculated separately for participants of European and East Asian ancestry using multivariate logistic regression. The impact of multiple comparisons was assessed by correcting for the false discovery rate within each DNA repair pathway. Interactions between several breast cancer risk factors and DNA repair SNPs were also evaluated. One SNP (rs3213282) in the gene XRCC1 was associated with an increased risk of breast cancer in the dominant model of inheritance following adjustment for the false discovery rate (P < 0.05), although no associations were observed for other DNA repair SNPs. Interactions of six SNPs in multiple DNA repair pathways with physical activity were evident prior to correction for FDR, following which there was support for only one of the interaction terms (P < 0.05). No consistent associations between variants in DNA repair genes and breast cancer risk or their modification by breast cancer risk factors were observed.

  10. Role of Deubiquitinating Enzymes in DNA Repair

    PubMed Central

    2015-01-01

    Both proteolytic and nonproteolytic functions of ubiquitination are essential regulatory mechanisms for promoting DNA repair and the DNA damage response in mammalian cells. Deubiquitinating enzymes (DUBs) have emerged as key players in the maintenance of genome stability. In this minireview, we discuss the recent findings on human DUBs that participate in genome maintenance, with a focus on the role of DUBs in the modulation of DNA repair and DNA damage signaling. PMID:26644404

  11. Spinal Cord Repair with Engineered Nervous Tissue

    DTIC Science & Technology

    2011-10-01

    funded grant, we demonstrated proof-of-concept success of bridging a lateral hemisection of the rat spinal cord with engineered (“stretch-grown...AD_________________ Award Number: W81XWH-10-1-0941 TITLE: Spinal Cord Repair with Engineered...5a. CONTRACT NUMBER Spinal Cord Repair with Engineered Nervous Tissue 5b. GRANT NUMBER W81XWH-10-1-0941 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR

  12. Spinal Cord Repair with Engineered Nervous Tissue

    DTIC Science & Technology

    2012-10-01

    success of bridging a lateral hemisection in the rat spinal cord with engineered (“stretch-grown”) living nervous tissue constructs 2 . For the current...AD_________________ Award Number: W81XWH-10-1-0941 TITLE: Spinal Cord Repair with Engineered...SUBTITLE Spinal Cord Repair with Engineered Nervous Tissue 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-10-1-0941 5c. PROGRAM ELEMENT NUMBER 6

  13. Analysis of Commercial Unsaturated Polyester Repair Resins

    DTIC Science & Technology

    2009-07-01

    Ostwald-de Waele power-law model parameters for repair putties. .....................29  Table 13. Dynamic mechanical properties for Bondo resins... Waele power-law model was used to fit the experimental data (37, 38): n–1η= Kγ , (6) where K reflects the magnitude of the viscosity, with higher...The Ostwald-de Waele power-law model parameters for repair putties. Power Law Parameter BG BBF BAP BBR BFR EG EBF ERAGE

  14. [Late vaginal mesh exposure after prolapse repair].

    PubMed

    Chanelles, O; Poncelet, C

    2010-12-01

    Mesh exposure is the major complication of vaginal prolapse repair. Incidence rates are variable according to the series. Mesh exposure usually occurs during the year following the intervention. We report here the first case of a patient with a late exposure of an anterior vaginal mesh 4 years after a surgical cystocele repair. The mesh has been easily removed at the operative theatre by vaginal approach.

  15. Nuclear position dictates DNA repair pathway choice

    PubMed Central

    Lemaître, Charlène; Grabarz, Anastazja; Tsouroula, Katerina; Andronov, Leonid; Furst, Audrey; Pankotai, Tibor; Heyer, Vincent; Rogier, Mélanie; Attwood, Kathleen M.; Kessler, Pascal; Dellaire, Graham; Klaholz, Bruno; Reina-San-Martin, Bernardo; Soutoglou, Evi

    2014-01-01

    Faithful DNA repair is essential to avoid chromosomal rearrangements and promote genome integrity. Nuclear organization has emerged as a key parameter in the formation of chromosomal translocations, yet little is known as to whether DNA repair can efficiently occur throughout the nucleus and whether it is affected by the location of the lesion. Here, we induce DNA double-strand breaks (DSBs) at different nuclear compartments and follow their fate. We demonstrate that DSBs induced at the nuclear membrane (but not at nuclear pores or nuclear interior) fail to rapidly activate the DNA damage response (DDR) and repair by homologous recombination (HR). Real-time and superresolution imaging reveal that DNA DSBs within lamina-associated domains do not migrate to more permissive environments for HR, like the nuclear pores or the nuclear interior, but instead are repaired in situ by alternative end-joining. Our results are consistent with a model in which nuclear position dictates the choice of DNA repair pathway, thus revealing a new level of regulation in DSB repair controlled by spatial organization of DNA within the nucleus. PMID:25366693

  16. Techniques for aortic arch endovascular repair.

    PubMed

    Hongku, Kiattisak; Dias, Nuno; Sonesson, Bjorn; Resch, Timothy

    2016-06-01

    This article reviews endovascular strategies for aortic arch repair. Open repair remains the gold standard particularly for good risk patients. Endovascular treatment potentially offers a less invasive repair. Principles, technical considerations, devices and outcomes of each technique are discussed and summarized. Hybrid repair combines less invasive revascularization options, instead of arch replacement while extending stent-graft into the arch. Outcomes vary with regard to extent of repair and aortic arch pathologies treated. Results of arch chimney and other parallel graft techniques perhaps make it a less preferable choice for elective cases. However, they are very appealing options for urgent or bailout situations. Fenestrated stent-grafting is subjected to many technical challenges in aortic arch due to difficulties in stent-graft orientation and fenestration positioning. In situ fenestration techniques emerge to avoid these problems, but durability of stent-grafts after fenestration and ischemic consequences of temporary carotid arteries coverage raises some concern total arch repair using this technique. Arch branched graft is a new technology. Early outcomes did not meet the expectation; however the results have been improving after its learning curve period. Refining stent-graft technologies and implantation techniques positively impact outcomes of endovascular approaches.

  17. Repair of radiation damage in mammalian cells

    SciTech Connect

    Setlow, R.B.

    1981-01-01

    The responses, such as survival, mutation, and carcinogenesis, of mammalian cells and tissues to radiation are dependent not only on the magnitude of the damage to macromolecular structures - DNA, RNA, protein, and membranes - but on the rates of macromolecular syntheses of cells relative to the half-lives of the damages. Cells possess a number of mechanisms for repairing damage to DNA. If the repair systems are rapid and error free, cells can tolerate much larger doses than if repair is slow or error prone. It is important to understand the effects of radiation and the repair of radiation damage because there exist reasonable amounts of epidemiological data that permits the construction of dose-response curves for humans. The shapes of such curves or the magnitude of the response will depend on repair. Radiation damage is emphasized because: (a) radiation dosimetry, with all its uncertainties for populations, is excellent compared to chemical dosimetry; (b) a number of cancer-prone diseases are known in which there are defects in DNA repair and radiation results in more chromosomal damage in cells from such individuals than in cells from normal individuals; (c) in some cases, specific radiation products in DNA have been correlated with biological effects, and (d) many chemical effects seem to mimic radiation effects. A further reason for emphasizing damage to DNA is the wealth of experimental evidence indicating that damages to DNA can be initiating events in carcinogenesis.

  18. Laparoscopic repair of recurrent groin hernias.

    PubMed

    Felix, E L; Michas, C; McKnight, R L

    1994-06-01

    Between November 1991 and May 1993, 54 recurrent groin hernias were laparoscopically repaired in 50 patients. Forty-eight were men and two were women. Forty-six recurrent hernias were unilateral and four bilateral. Twenty-five were direct, 19 indirect, 10 pantaloon, and two had a femoral component. In only 10 patients was the contralateral side normal. In 27 patients, the other side had been previously repaired, and in 13 they had a new contralateral hernia. A transabdominal preperitoneal technique was used to dissect and repair the entire floor in all patients. A single sheet of polypropylene mesh was used in the repair of the women patients, and a double-buttress technique with the first sheet slitted for the cord was used for the men. Patients were examined every 3 months for the first year and at 6-month intervals thereafter. Follow-up ranged from 1 to 18 months with a mean of 8 months. No patient was lost to follow-up, and no recurrence was observed. Patients returned to normal activity in an average of 1 week. Seroma, which resolved spontaneously, was the most common complication. The overall short-term results suggested that a laparoscopic mesh buttressed repair of recurrent groin hernias is technically feasible and can eliminate early rerecurrence of the hernia so commonly seen after repair of recurrent hernias.

  19. Subsidence resistant repair of a block basement

    SciTech Connect

    Mahar, J.W.; Marino, G.G.; Murphy, E.; Farnetti, J.

    1998-12-31

    A one story house was damaged by mine subsidence movement. The house is located in a small subsidence sag and is experiencing differential settlement and compressive ground strains. Instead of waiting for the ground movements to eventually stop, The Illinois Mine Subsidence Insurance Fund developed a permanent repair scheme that was implemented at the same time damaging mine subsidence movement was affecting the structure. This repair provided a significant structural resistance against the anticipated residual mine subsidence movement and was aesthetically acceptable to the homeowners. The repair consisted of epoxying vertical and horizontal steel straps and then applying a cover coat of fiber-cement on the unreinforced concrete block basement walls. The repair scheme was relatively untried, but had been successfully researched. This paper provides information on the mine subsidence movement/damage, the design concepts of steel strap/fiber-cement repair, construction details, performance and costs. Other applications of the use of the steel strap repair method are also discussed for releveling of a building and/or correcting subsidence damage to structures located in the tension zone.

  20. Self-repair of cracks in brittle material systems

    NASA Astrophysics Data System (ADS)

    Dry, Carolyn M.

    2016-04-01

    One of the most effective uses for self repair is in material systems that crack because the cracks can allow the repair chemical to flow into the crack damage sites in all three dimensions. In order for the repair chemical to stay in the damage site and flow along to all the crack and repair there must be enough chemical to fill the entire crack. The repair chemical must be designed appropriately for the particular crack size and total volume of cracks. In each of the three examples of self repair in crackable brittle systems, the viscosity and chemical makeup and volume of the repair chemicals used is different for each system. Further the chemical delivery system has to be designed for each application also. Test results from self repair of three brittle systems are discussed. In "Self Repair of Concrete Bridges and Infrastructure" two chemicals were used due to different placements in bridges to repair different types of cracks- surface shrinkage and shear cracks, In "Airplane Wings and Fuselage, in Graphite" the composite has very different properties than the concrete bridges. In the graphite for airplane components the chemical also had to survive the high processing temperatures. In this composite the cracks were so definite and deep and thin that the repair chemical could flow easily and repair in all layers of the composite. In "Ceramic/Composite Demonstrating Self Repair" the self repair system not only repaired the broken ceramic but also rebounded the composite to the ceramic layer

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

    SciTech Connect

    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.

  2. The impact of heterochromatin on DSB repair.

    PubMed

    Goodarzi, Aaron A; Noon, Angela T; Jeggo, Penny A

    2009-06-01

    DNA NHEJ (non-homologous end-joining) is the major DNA DSB (double-strand break) repair pathway in mammalian cells. Although NHEJ-defective cell lines show marked DSB-repair defects, cells defective in ATM (ataxia telangiectasia mutated) repair most DSBs normally. Thus NHEJ functions independently of ATM signalling. However, approximately 15% of radiation-induced DSBs are repaired with slow kinetics and require ATM and the nuclease Artemis. DSBs persisting in the presence of an ATM inhibitor, ATMi, localize to heterochromatin, suggesting that ATM is required for repairing DSBs arising within or close to heterochromatin. Consistent with this, we show that siRNA (small interfering RNA) of key heterochromatic proteins, including KAP-1 [KRAB (Krüppel-associated box) domain-associated protein 1], HP1 (heterochromatin protein 1) and HDAC (histone deacetylase) 1/2, relieves the requirement for ATM for DSB repair. Furthermore, ATMi addition to cell lines with genetic alterations that have an impact on heterochromatin, including Suv39H1/2 (suppressor of variegation 3-9 homologue 1/2)-knockout, ICFa (immunodeficiency, centromeric region instability, facial anomalies syndrome type a) and Hutchinson-Guilford progeria cell lines, fails to have an impact on DSB repair. KAP-1 is a highly dose-dependent, transient and ATM-specific substrate, and mutation of the ATM phosphorylation site on KAP-1 influences DSB repair. Collectively, the findings show that ATM functions to overcome the barrier to DSB repair posed by heterochromatin. However, even in the presence of ATM, gamma-H2AX (phosphorylated histone H2AX) foci form on the periphery rather than within heterochromatic centres. Finally, we show that KAP-1's association with heterochromatin is diminished as cells progress through mitosis. We propose that KAP-1 is a critical heterochromatic factor that undergoes specific modifications to promote DSB repair and mitotic progression in a manner that allows localized and transient

  3. F-111 Adhesive Bonded Repairs Assessment Program - Progress Report 2: Analysis of FM300-2K Repairs

    DTIC Science & Technology

    2015-01-01

    on the measured repair strength (due to the potential effect of substrate curvature on test piston misalignment), repair location did not appear to...be a major factor influencing the measured repair strength. The previous report also found that the repair age, based on either total accumulated...time or total number of flight hours since application, did not appear to have an effect on the measured repair strength. However, UNCLASSIFIED DSTO

  4. General Mechanical Repair. Minor Automotive Maintenance, Small Engine [Repair, and] Welding: Student Manual.

    ERIC Educational Resources Information Center

    Hamlin, Larry

    This document is a student manual for a general mechanical repair course. Following a list of common essential elements of trade and industrial education, the manual is divided into three sections. The first section, on minor automotive maintenance, contains 13 units: automotive shop safety; engine principles; fuel system operation and repair;…

  5. Metrics for Industrial Electronics, Radio-TV Repair, Audio Equipment Repair.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students in industrial electronics, radio-tv repair, and audio equipment repair, this instructional package is one of eight for the manufacturing occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who…

  6. Proximal Contact Repair of Complex Amalgam Restorations.

    PubMed

    Zguri, M N; Casey, J A; Jessup, J P; Vandewalle, K S

    2017-01-12

    The carving of a complex amalgam restoration may occasionally result in light proximal contact with the adjacent tooth. The purpose of this study was to investigate the strength of complex amalgam restorations repaired with a proximal slot amalgam preparation. Extracted human third molars of similar coronal size were sectioned 1 mm apical to the height of the contour using a saw and were randomly distributed into 9 groups of 10 teeth each. One pin was placed at each line angle of the flattened dentinal tooth surface. A metal matrix band was placed and an admixed alloy was condensed and carved to create a full crown contour but with a flat occlusal surface. A proximal slot was prepared with or without a retention groove and repaired using a single-composition spherical amalgam 15 minutes, 24 hours, one week, or six months after the initial crown condensation. The specimens were stored for 24 hours in 37°C water before fracture at the marginal ridge using a round-ended blade in a universal testing machine. The control group was not repaired. The mean maximum force in newtons and standard deviation were determined per group. Data were analyzed with a 2-way analysis of variance as well as Tukey and Dunnett tests (α=0.05). Significant differences were found between groups based on type of slot preparation (p=0.017) but not on time (p=0.327), with no significant interaction (p=0.152). No significant difference in the strength of the marginal ridge was found between any repair group and the unrepaired control group (p>0.076). The proximal repair strength of a complex amalgam restoration was not significantly different from an unrepaired amalgam crown. Placing a retention groove in the proximal slot preparation resulted in significantly greater fracture strength than a slot with no retention grooves. Time of repair had no significant effect on the strength of the repair.

  7. DNA damage and repair in mutagenesis and carcinogenesis: implications of structure-activity relationships for cross-species extrapolation.

    PubMed

    Vogel, E W; Nivard, M J; Ballering, L A; Bartsch, H; Barbin, A; Nair, J; Comendador, M A; Sierra, L M; Aguirrezabalaga, I; Tosal, L; Ehrenberg, L; Fuchs, R P; Janel-Bintz, R; Maenhaut-Michel, G; Montesano, R; Hall, J; Kang, H; Miele, M; Thomale, J; Bender, K; Engelbergs, J; Rajewsky, M F

    1996-06-12

    Previous studies on structure-activity relationships (SARs) between types of DNA modifications and tumour incidence revealed linear positive relationships between the log TD50 estimates and s-values for a series of mostly monofunctional alkylating agents. The overall objective of this STEP project was to further elucidate the mechanistic principles underlying these correlations, because detailed knowledge on mechanisms underlying the formation of genotoxic damage is an absolute necessity for establishing guidance values for exposures to genotoxic agents. The analysis included: (1) the re-calculation and further extension of TD50 values in mmol/kg body weight for chemicals carcinogenic in rodents. This part further included the checking up data for Swain-Scott s-values and the use of the covalent binding index (CBI); (2) the elaboration of genetic toxicity including an analysis of induced mutation spectra in specific genes at the DNA level, i.e., the vermilion gene of Drosophila, a plasmid system (pX2 assay) and the HPRT gene in cultured mammalian cells (CHO-9); and (3) the measurement of specific DNA alkylation adducts in animal models (mouse, rat, hamster) and mammalian cells in culture. The analysis of mechanisms controlling the expression of mammalian DNA repair genes (alkyltransferases, glycosylases) as a function of the cell type, differentiation stage, and cellular microenvironment in mammalian cells. The 3 classes of genotoxic carcinogens selected for the project were: (1) chemicals forming monoalkyl adducts upon interaction with DNA; (2) genotoxins capable of forming DNA etheno-adducts; and (3) N-substituted aryl compounds forming covalent adducts at the C8 position of guanine in DNA. In general, clear SARs and AARs (activity-activity relationships) between physiochemical parameters (s-values, O6/N7-alkylguanine ratios, CBI), carcinogenic potency in rodents and several descriptors of genotoxic activity in germ cells (mouse, Drosophila) became apparent when

  8. A prospective study of bilateral inguinal hernia repair.

    PubMed Central

    Serpell, J. W.; Johnson, C. D.; Jarrett, P. E.

    1990-01-01

    A prospective study of outcome after inguinal hernia repair in patients undergoing simultaneous repair of bilateral hernias (n = 31), sequential repair of bilateral hernias (n = 5), and unilateral hernia repair (n = 75) is reported. There were no differences in wound complications, post-operative respiratory complications, or other adverse effects in the three groups. Operating time was similar in the unilateral and bilateral simultaneous repairs (median 55 min), but was longer (100 min) for the combination of two sequential repairs. Hospital stay was shortest for patients undergoing unilateral repair (2 days) but was less with bilateral simultaneous repair (4 days) than after two sequential repairs (total of 6 days). There were 12 (11%) wound complications of which five (5%) were infections. There was no difference in complication rate between unilateral and bilateral hernia repair. Postoperative recovery was assessed prospectively and was recorded at 1 month. There was no difference between unilateral and bilateral simultaneous repairs in the number of days before the patient was able to climb stairs easily, drive a car or return to work. The duration of the requirement for analgesia was similar in each group. We conclude that bilateral simultaneous hernia repair can be carried out with no greater morbidity than a unilateral repair, and the return to normal activity is as rapid. Bilateral hernias should be repaired simultaneously rather than sequentially. PMID:2221764

  9. Wellbore Seal Repair Using Nanocomposite Materials

    SciTech Connect

    Stormont, John

    2016-08-31

    Nanocomposite wellbore repair materials have been developed, tested, and modeled through an integrated program of laboratory testing and numerical modeling. Numerous polymer-cement nanocomposites were synthesized as candidate wellbore repair materials using various combinations of base polymers and nanoparticles. Based on tests of bond strength to steel and cement, ductility, stability, flowability, and penetrability in opening of 50 microns and less, we identified Novolac epoxy reinforced with multi-walled carbon nanotubes and/or alumina nanoparticles to be a superior wellbore seal material compared to conventional microfine cements. A system was developed for testing damaged and repaired wellbore specimens comprised of a cement sheath cast on a steel casing. The system allows independent application of confining pressures and casing pressures while gas flow is measured through the specimens along the wellbore axis. Repair with the nanocomposite epoxy base material was successful in dramatically reducing the flow through flaws of various sizes and types, and restoring the specimen comparable to an intact condition. In contrast, repair of damaged specimens with microfine cement was less effective, and the repair degraded with application of stress. Post-test observations confirm the complete penetration and sealing of flaws using the nanocomposite epoxy base material. A number of modeling efforts have supported the material development and testing efforts. We have modeled the steel-repair material interface behavior in detail during slant shear tests, which we used to characterize bond strength of candidate repair materials. A numerical model of the laboratory testing of damaged wellbore specimens was developed. This investigation found that microannulus permeability can satisfactorily be described by a joint model. Finally, a wellbore model has been developed that can be used to evaluate the response of the wellbore system (casing, cement, and microannulus

  10. Umbilical Hernia Repair: Analysis After 934 Procedures.

    PubMed

    Porrero, José L; Cano-Valderrama, Oscar; Marcos, Alberto; Bonachia, Oscar; Ramos, Beatriz; Alcaide, Benito; Villar, Sol; Sánchez-Cabezudo, Carlos; Quirós, Esther; Alonso, María T; Castillo, María J

    2015-09-01

    There is a lack of consensus about the surgical management of umbilical hernias. The aim of this study is to analyze the medium-term results of 934 umbilical hernia repairs. In this study, 934 patients with an umbilical hernia underwent surgery between 2004 and 2010, 599 (64.1%) of which were evaluated at least one year after the surgery. Complications, recurrence, and the reoperation rate were analyzed. Complications were observed in 5.7 per cent of the patients. With a mean follow-up time of 35.5 months, recurrence and reoperation rates were 3.8 per cent and 4.7 per cent, respectively. A higher percentage of female patients (60.9 % vs 29 %, P = 0.001) and a longer follow-up time (47.4 vs 35 months, P = 0.037) were observed in patients who developed a recurrence. No significant differences were observed between complications and the reoperation rate in patients who underwent Ventralex(®) preperitoneal mesh reinforcement and suture repair; however, a trend toward a higher recurrence rate was observed in patients with suture repair (6.5 % vs 3.2 %, P = 0.082). Suture repair had lower recurrence and reoperation rates in patients with umbilical hernias less than 1 cm. Suture repair is an appropriate procedure for small umbilical hernias; however, for larger umbilical hernias, mesh reinforcement should be considered.

  11. Successful repair of a 6 meter battery

    SciTech Connect

    Nay, K.; Gratson, M.; Wash, S.; Sundholm, J.L.; Hippe, W.; Ramani, R.V.

    1996-12-31

    Following a two-year construction period, LTV Steel Company commissioned a new six-meter coke oven battery and ancillary facilities in December 1981 at the S. Chicago Works. The battery is a 60-oven Didier grouped flue underjet design capable of firing coke oven gas and blast furnace gas. In late 1990, coke side refractory damage in the form of severe spalls and holes in the walls were observed. Numerous repair techniques--welding, guniting, panel patching, end flue repairs using zero expansion brick--were employed as interim measures until a comprehensive repair plan could be implemented. A repair plan (primarily for coke side flues) was developed which envisioned end flue repairs on six walls per year beginning in late 1991, early 1992 depending on refractory delivery. However, in late 1992 it became apparent that the coke side deterioration was occurring faster than expected and that extensive pusher side deterioration was also occurring. Because of these developments, another battery inspection was performed. On the basis of this inspection, it was determined that a major rehabilitation would be required to assure long-term, environmentally acceptable operation of the battery.

  12. DNA Repair and Personalized Breast Cancer Therapy

    PubMed Central

    Li, Shu-Xia; Sjolund, Ashley; Harris, Lyndsay; Sweasy, Joann B.

    2010-01-01

    Personalized cancer therapy is likely to be one of the next big advances in our search for a cure for cancer. To be able to treat people in an individualized manner, researchers need to know a great deal about their genetic constitution and the DNA repair status of their tumors. Specific knowledge is required regarding the polymorphisms individuals carry and how these polymorphisms influence responses to therapy. Researchers are actively engaged in biomarker discovery and validation for this purpose. In addition, the design of clinical trials must be reassessed to include new information on biomarkers and drug responses. In this review, we focus on personalized breast cancer therapy. The hypothesis we focus upon in this review is that there is connection between the DNA repair profile of individuals, their breast tumor subtypes, and their responses to cancer therapy. We first briefly review cellular DNA repair pathways that are likely to be impacted by breast cancer therapies. Next, we review the phenotypes of breast tumor subtypes with an emphasis on how a DNA repair deficiency might result in tumorigenesis itself and lead to the chemotherapeutic responses that are observed. Specific examples of breast tumor subtypes and their responses to cancer therapy are given, and we discuss possible DNA repair mechanisms that underlie the responses of tumors to various chemotherapeutic agents. Much is known about breast cancer subtypes and the way each of these subtypes responds to chemotherapy. In addition, we discuss novel design of clinical trials that incorporates rapidly emerging information on biomarkers. PMID:20872853

  13. Nucleotide excision repair in Escherichia coli.

    PubMed Central

    Van Houten, B

    1990-01-01

    One of the best-studied DNA repair pathways is nucleotide excision repair, a process consisting of DNA damage recognition, incision, excision, repair resynthesis, and DNA ligation. Escherichia coli has served as a model organism for the study of this process. Recently, many of the proteins that mediate E. coli nucleotide excision have been purified to homogeneity; this had led to a molecular description of this repair pathway. One of the key repair enzymes of this pathway is the UvrABC nuclease complex. The individual subunits of this enzyme cooperate in a complex series of partial reactions to bind to and incise the DNA near a damaged nucleotide. The UvrABC complex displays a remarkable substrate diversity. Defining the structural features of DNA lesions that provide the specificity for damage recognition by the UvrABC complex is of great importance, since it represents a unique form of protein-DNA interaction. Using a number of in vitro assays, researchers have been able to elucidate the action mechanism of the UvrABC nuclease complex. Current research is devoted to understanding how these complex events are mediated within the living cell. PMID:2181258

  14. Mechanical injury and repair of cells

    NASA Technical Reports Server (NTRS)

    Miyake, Katsuya; McNeil, Paul L.

    2003-01-01

    OBJECTIVE: To concisely review the field of cell plasma membrane disruption (torn cell surface) and repair. MAIN POINTS: Plasma membrane disruption is a common form of cell injury under physiologic conditions, after trauma, in certain muscular dystrophies, and during certain forms of clinical intervention. Rapid repair of a disruption is essential to cell survival and involves a complex and active cell response that includes membrane fusion and cytoskeletal activation. Tissues, such as cardiac and skeletal muscle, adapt to a disruption injury by hypertrophying. Cells adapt by increasing the efficiency of their resealing response. CONCLUSION: Plasma membrane disruption is an important cellular event in both health and disease. The disruption repair mechanism is now well understood at the cellular level, but much remains to be learned at the molecular level. Cell and tissue level adaptational responses to the disruption either prevent its further occurrence or facilitate future repairs. Therapeutically useful drugs might result if, using this accumulating knowledge, chemical agents can be developed that can enhance repair or adaptive responses.

  15. DNA repair responses in human skin cells

    SciTech Connect

    Hanawalt, P.C.; Liu, S.C.; Parsons, C.S.

    1981-07-01

    Sunlight and some environmental chemical agents produce lesions in the DNA of human skin cells that if unrepaired may interfere with normal functioning of these cells. The most serious outcome of such interactions may be malignancy. It is therefore important to develop an understanding of mechanisms by which the lesions may be repaired or tolerated without deleterious consequences. Our models for the molecular processing of damaged DNA have been derived largely from the study of bacterial systems. Some similarities but significant differences are revealed when human cell responses are tested against these models. It is also of importance to learn DNA repair responses of epidermal keratinocytes for comparison with the more extensive studies that have been carried out with dermal fibroblasts. Our experimental results thus far indicate similarities for the excision-repair of ultraviolet-induced pyrimidine dimers in human keratinocytes and fibroblasts. Both the monoadducts and the interstrand crosslinks produced in DNA by photoactivated 8-methoxypsoralen (PUVA) can be repaired in normal human fibroblasts but not in those from xeroderma pigmentosum patients. The monoadducts, like pyrimidine dimers, are probably the more mutagenic/carcinogenic lesions while the crosslinks are less easily repaired and probably result in more effective blocking of DNA function. It is suggested that a split-dose protocol that maximizes the production of crosslinks while minimizing the yield of monoadducts may be more effective and potentially less carcinogenic than the single ultraviolet exposure regimen in PUVA therapy for psoriasis.

  16. In utero repair of spina bifida.

    PubMed

    Moldenhauer, Julie S

    2014-08-01

    Open spina bifida or myelomeningocele (MMC) is the most common congenital malformation of the central nervous system compatible with long-term survival and is associated with significant lifelong disabilities. Postnatal care of MMC involves covering the exposed spinal cord, infection prevention, and ventricular shunting for hydrocephalus. The aim of postnatal MMC surgery is not to reverse or prevent the neurologic injury seen in MMC, but to palliate. The neurologic defects result from primary incomplete neurulation and secondary chronic in utero damage to the exposed neural elements through mechanical and chemical trauma-the two-hit hypothesis. With the ability to accurately diagnose spina bifida prenatally and the concept of the two-hit hypothesis, in utero repair to decrease exposure and alter the antenatal course of neurologic destruction was conceived. Through animal models and human pilot studies, the feasibility of fetal spina bifida repair was demonstrated. Subsequently, the prospective randomized multicenter Management of Myelomeningocele Study (MOMS trial) revealed a decreased need for shunting, reversal of hindbrain herniation, and preservation of neurologic function, making in utero repair an accepted care alternative for select women carrying a fetus with spina bifida. This article will highlight the background and rationale for in utero repair, and the progression to becoming an alternative standard of care. The future directions of fetal spina bifida repair will also be addressed.

  17. Repair of mismatched basepairs in mammalian DNA

    SciTech Connect

    Taylor, J.H.; Hare, J.T.

    1991-08-01

    We have concentrated on three specific areas of our research plan. Our greatest emphasis is on the role of single strand nicks in influencing template strand selection in mismatch repair. We have found, that the ability of a nick in one strand to influence which strand is repaired is not a simple function of distance from the mismatched site but rather that an hot spot where a nick is more likely to have an influence can exist. The second line was production of single-genotype heteroduplexes in order to examine independently the repair of T/G and A/C mispairs within the same sequence context as in our mixed mispair preparations. We have shown preparations of supercoiled heteroduplex can be prepared that were exclusively T/G or exclusively A/C at the mispair site. The third effort has been to understand the difference in repair bias of different cell lines or different transfection conditions as it may relate to different repair systems in the cell. We have identified some of the sources of variation, including cell cycle position. We hope to continue this work to more precisely identify the phase of the cell cycle.

  18. Transcription-coupled repair: an update.

    PubMed

    Spivak, Graciela

    2016-11-01

    Nucleotide excision repair (NER) is a versatile pathway that removes helix-distorting DNA lesions from the genomes of organisms across the evolutionary scale, from bacteria to humans. The serial steps in NER involve recognition of lesions, adducts or structures that disrupt the DNA double helix, removal of a short oligonucleotide containing the offending lesion, synthesis of a repair patch copying the opposite undamaged strand, and ligation, to restore the DNA to its original form. Transcription-coupled repair (TCR) is a subpathway of NER dedicated to the repair of lesions that, by virtue of their location on the transcribed strands of active genes, encumber elongation by RNA polymerases. In this review, I report on recent findings that contribute to the elucidation of TCR mechanisms in the bacterium Escherichia coli, the yeast Saccharomyces cerevisiae and human cells. I review general models for the biochemical pathways and how and when cells might choose to utilize TCR or other pathways for repair or bypass of transcription-blocking DNA alterations.

  19. Repair of DNA Double-Strand Breaks

    NASA Astrophysics Data System (ADS)

    Falk, Martin; Lukasova, Emilie; Kozubek, Stanislav

    The genetic information of cells continuously undergoes damage induced by intracellular processes including energy metabolism, DNA replication and transcription, and by environmental factors such as mutagenic chemicals and UV and ionizing radiation. This causes numerous DNA lesions, including double strand breaks (DSBs). Since cells cannot escape this damage or normally function with a damaged genome, several DNA repair mechanisms have evolved. Although most "single-stranded" DNA lesions are rapidly removed from DNA without permanent damage, DSBs completely break the DNA molecule, presenting a real challenge for repair mechanisms, with the highest risk among DNA lesions of incorrect repair. Hence, DSBs can have serious consequences for human health. Therefore, in this chapter, we will refer only to this type of DNA damage. In addition to the biochemical aspects of DSB repair, which have been extensively studied over a long period of time, the spatio-temporal organization of DSB induction and repair, the importance of which was recognized only recently, will be considered in terms of current knowledge and remaining questions.

  20. Combining rhinoplasty with septal perforation repair.

    PubMed

    Foda, Hossam M T; Magdy, Emad A

    2006-11-01

    A combined septal perforation repair and rhinoplasty was performed in 80 patients presenting with septal perforations (size 1 to 5 cm) and external nasal deformities. The external rhinoplasty approach was used for all cases and the perforation was repaired using bilateral intranasal mucosal advancement flaps with a connective tissue interposition graft in between. Complete closure of the perforation was achieved in 90% of perforations of size up to 3.5 cm and in only 70% of perforations that were larger than 3.5 cm. Cosmetically, 95% were very satisfied with their aesthetic result. The external rhinoplasty approach proved to be very helpful in the process of septal perforation repair especially in large and posteriorly located perforations and in cases where the caudal septal cartilage was previously resected. Our results show that septal perforation repair can be safely combined with rhinoplasty and that some of the routine rhinoplasty maneuvers, such as medial osteotomies and dorsal lowering, could even facilitate the process of septal perforation repair.

  1. Repair to the Huygens probe

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Jet Propulsion Laboratory (JPL) workers examine the Huygens probe after removal from the Cassini spacecraft in the Payload Hazardous Servicing Facility (PHSF) at KSC. The spacecraft was returned to the PHSF after damage to the thermal insulation was discovered inside Huygens from an abnormally high flow of conditioned air. The damage required technicians to inspect the inside of the probe, repair the insulation, and clean the instruments. After returning from the PHSF to Launch Pad 40 at Cape Canaveral Air Station, Cassini/Huygens launched successfully in October 1997, and reached Saturn in July of 2004. Scientific instruments carried aboard the Cassini orbiter will study Saturn's atmosphere, magnetic field, rings, and several moons, while the Huygens probe will separate and land on the surface of Titan, Saturn's largest moon. The Cassini-Huygens mission owes its name to the Dutch astronomer Christiaan Huygens and Italian astronomer Giovanni Domenico Cassini. Both had spectacular careers as observers of the heavens, which included important discoveries about Saturn and its satellites. Huygens (1629-1695) discovered Saturn's largest moon, Titan, in 1655 and in 1656 described the shape and phase changes of Saturn's rings. Cassini (1625-1712) was the first to observe four of Saturn's moons, Iapetus, Rhea, Tethys, and Dione, in the 1670s and 1680s. He also, in 1675, discovered the gap in Saturn's rings, now called the Cassini Division, and proposed that the rings were formed from many tiny particles. Cassini-Huygens is a joint mission of NASA, the European Space Agency (ESA), and the Italian Space Agency, Agenzia Spaziale Italiana (ASI). JPL is managing the Cassini project for NASA. The mission was proposed in November 1982 by a group of European and American scientists from the European Science Foundation and the National Academy of Sciences. The Solar System Exploration Committee of the NASA Advisory Council endorsed the idea in April 1983, and NASA and ESA began a

  2. Characterization of Homogeneous, Cooperative Protein-DNA Clusters by Sedimentation Equilibrium Analytical Ultracentrifugation and Atomic Force Microscopy.

    PubMed

    Tessmer, Ingrid; Fried, Michael G

    2015-01-01

    Strong, positively cooperative binding can lead to the clustering of proteins on DNA. Here, we describe one approach to the analysis of such clusters. Our example is based on recent studies of the interactions of O(6)-alkylguanine DNA alkyltransferase (AGT) with high-molecular-weight DNAs (Adams et al., 2009; Tessmer, Melikishvili, & Fried, 2012). Cooperative cluster size distributions are predicted using the simplest homogeneous binding and cooperativity (HBC) model, together with data obtained by sedimentation equilibrium analysis. These predictions are tested using atomic force microscopy imaging; for AGT, measured cluster sizes are found to be significantly smaller than those predicted by the HBC model. A mechanism that may account for cluster size limitation is briefly discussed.

  3. Fabrication Flaws in Reactor Pressure Vessel Repair Welds

    SciTech Connect

    Schuster, George J.; Doctor, Steven R.

    2007-12-01

    This paper describes the fabrication flaw distribution and characterization in the repair weld metal of reactor pressure vessels. This work indicates that the large flaws occur in these repairs. These results show that repair flaws are complex in composition and sometimes include cracks on the repair ends. Parametric analysis using an exponential fit is performed on the data. A description of repair flaw morphology is provided. Fabrication flaws in repairs are characterized using high sensitivity nondestructive ultrasonic testing, validation by other nondestructive evaluation (NDE) techniques, and complemented by destructive testing.

  4. Current options in inguinal hernia repair in adult patients

    PubMed Central

    Kulacoglu, H

    2011-01-01

    Inguinal hernia is a very common problem. Surgical repair is the current approach, whereas asymptomatic or minimally symptomatic hernias may be good candidate for watchful waiting. Prophylactic antibiotics can be used in centers with high rate of wound infection. Local anesthesia is a suitable and economic option for open repairs, and should be popularized in day-case setting. Numerous repair methods have been described to date. Mesh repairs are superior to "nonmesh" tissue-suture repairs. Lichtenstein repair and endoscopic/laparoscopic techniques have similar efficacy. Standard polypropylene mesh is still the choice, whereas use of partially absorbable lightweight meshes seems to have some advantages. PMID:22435019

  5. Alkylation damage repair in mammalian genomes

    SciTech Connect

    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.

  6. Alkylation damage repair in mammalian genomes

    SciTech Connect

    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.

  7. Chromatin Remodeling, DNA Damage Repair and Aging

    PubMed Central

    Liu, Baohua; Yip, Raymond KH; Zhou, Zhongjun

    2012-01-01

    Cells are constantly exposed to a variety of environmental and endogenous conditions causing DNA damage, which is detected and repaired by conserved DNA repair pathways to maintain genomic integrity. Chromatin remodeling is critical in this process, as the organization of eukaryotic DNA into compact chromatin presents a natural barrier to all DNA-related events. Studies on human premature aging syndromes together with normal aging have suggested that accumulated damages might lead to exhaustion of resources that are required for physiological functions and thus accelerate aging. In this manuscript, combining the present understandings and latest findings, we focus mainly on discussing the role of chromatin remodeling in the repair of DNA double-strand breaks (DSBs) and regulation of aging. PMID:23633913

  8. Induced pluripotent stem cells in cartilage repair

    PubMed Central

    Lietman, Steven A

    2016-01-01

    Articular cartilage repair techniques are challenging. Human embryonic stem cells and induced pluripotent stem cells (iPSCs) theoretically provide an unlimited number of specialized cells which could be used in articular cartilage repair. However thus far chondrocytes from iPSCs have been created primarily by viral transfection and with the use of cocultured feeder cells. In addition chondrocytes derived from iPSCs have usually been formed in condensed cell bodies (resembling embryoid bodies) that then require dissolution with consequent substantial loss of cell viability and phenotype. All of these current techniques used to derive chondrocytes from iPSCs are problematic but solutions to these problems are on the horizon. These solutions will make iPSCs a viable alternative for articular cartilage repair in the near future. PMID:27004161

  9. Engineered neural tissue for peripheral nerve repair.

    PubMed

    Georgiou, Melanie; Bunting, Stephen C J; Davies, Heather A; Loughlin, Alison J; Golding, Jonathan P; Phillips, James B

    2013-10-01

    A new combination of tissue engineering techniques provides a simple and effective method for building aligned cellular biomaterials. Self-alignment of Schwann cells within a tethered type-1 collagen matrix, followed by removal of interstitial fluid produces a stable tissue-like biomaterial that recreates the aligned cellular and extracellular matrix architecture associated with nerve grafts. Sheets of this engineered neural tissue supported and directed neuronal growth in a co-culture model, and initial in vivo tests showed that a device containing rods of rolled-up sheets could support neuronal growth during rat sciatic nerve repair (5 mm gap). Further testing of this device for repair of a critical-sized 15 mm gap showed that, at 8 weeks, engineered neural tissue had supported robust neuronal regeneration across the gap. This is, therefore, a useful new approach for generating anisotropic engineered tissues, and it can be used with Schwann cells to fabricate artificial neural tissue for peripheral nerve repair.

  10. A Review on Perforation Repair Materials

    PubMed Central

    Veeramachaneni, Chandrasekhar; Majeti, Chandrakanth; Tummala, Muralidhar; Khiyani, Laxmi

    2015-01-01

    Perforation is an artificial communication between the root canal system and supporting tissues of the teeth. Root perforation complicates the treatment and deprives the prognosis if not properly managed. A wide variety of materials to seal the perforations have been suggested in literature. There are many comparative studies showing the efficacy of one material over the other. Literature shows many reviews on diagnosis, treatment plan and factors affecting prognosis of perforation repair; but none of these articles elaborated upon various materials available to seal the perforation. The present article aims at describing all the materials used for perforation repair from the past till date; it also offers a literature review of all the articles published over last four decades referred to the treatment of perforation with various root repair materials. PMID:26501031

  11. Transactivation of repair genes by BRCA1.

    PubMed

    El-Deiry, Wafik S

    2002-01-01

    Recent studies have identified a link between the BRCA1 tumor suppressor and transcriptional regulation of a group of genes involved in nucleotide excision repair. There is some controversy regarding the precise mechanism of upregulation of XPE DDB2 or XPC by BRCA1, with some evidence suggesting that p53 is involved in their regulation. Some evidence suggests BRCA1 may stabilize p53 and direct regulation of DNA repair genes, although how BRCA1 stabilizes p53 remains unclear and whether BRCA1 can upregulate DNA repair genes in a p53-independent manner remains a possibility. A transcriptional component to the action of BRCA1 and involvement of XP genes brings up new and interesting questions about breast cancer development and therapy.

  12. Learning to improve iterative repair scheduling

    NASA Technical Reports Server (NTRS)

    Zweben, Monte; Davis, Eugene

    1992-01-01

    This paper presents a general learning method for dynamically selecting between repair heuristics in an iterative repair scheduling system. The system employs a version of explanation-based learning called Plausible Explanation-Based Learning (PEBL) that uses multiple examples to confirm conjectured explanations. The basic approach is to conjecture contradictions between a heuristic and statistics that measure the quality of the heuristic. When these contradictions are confirmed, a different heuristic is selected. To motivate the utility of this approach we present an empirical evaluation of the performance of a scheduling system with respect to two different repair strategies. We show that the scheduler that learns to choose between the heuristics outperforms the same scheduler with any one of two heuristics alone.

  13. DNA repair in ischemic acute kidney injury.

    PubMed

    Pressly, Jeffrey D; Park, Frank

    2017-04-01

    Ischemia-reperfusion injury (IRI) is a common cause of acute kidney injury leading to an induction of oxidative stress, cellular dysfunction, and loss of renal function. DNA damage, including oxidative base modifications and physical DNA strand breaks, is a consequence of renal IRI. Like many other organs in the body, a redundant and highly conserved set of endogenous repair pathways have evolved to selectively recognize the various types of cellular DNA damage and combat its negative effects on cell viability. Severe damage to the DNA, however, can trigger cell death and elimination of the injured tubular epithelial cells. In this minireview, we summarize the state of the current field of DNA damage and repair in the kidney and provide some expected and, in some cases, unexpected effects of IRI on DNA damage and repair in the kidney. These findings may be applicable to other forms of acute kidney injury and could provide new opportunities for renal research.

  14. Exosomes and cardiac repair after myocardial infarction.

    PubMed

    Sahoo, Susmita; Losordo, Douglas W

    2014-01-17

    Myocardial infarction is a leading cause of death among all cardiovascular diseases. The analysis of molecular mechanisms by which the ischemic myocardium initiates repair and remodeling indicates that secreted soluble factors are key players in communication to local and distant tissues, such as bone marrow. Recently, actively secreted membrane vesicles, including exosomes, are being recognized as new candidates with important roles in intercellular and tissue-level communication. In this review, we critically examine the emerging role of exosomes in local and distant microcommunication mechanisms after myocardial infarction. A comprehensive understanding of the role of exosomes in cardiac repair after myocardial infarction could bridge a major gap in knowledge of the repair mechanism after myocardial injury.

  15. The tether inspection and repair experiment (TIRE)

    NASA Technical Reports Server (NTRS)

    Wood, George M.; Loria, Alberto; Harrison, James K.

    1988-01-01

    The successful development and deployment of reusable tethers for space applications will require methods for detecting, locating, and repairing damage to the tether. This requirement becomes especially important whenever the safety of the STS or the Space Station may be diminished or when critical supplies or systems would be lost in the event of a tether failure. A joint NASA/PSN study endeavor has recently been initiated to evaluate and address the problems to be solved for such an undertaking. The objectives of the Tether Inspection and Repair Experiment (TIRE) are to develop instrumentation and repair technology for specific classes of tethers defined as standards, and to demonstrate the technologies in ground-based and in-flight testing on the STS.

  16. Variation in Base Excision Repair Capacity

    PubMed Central

    Wilson, David M.; Kim, Daemyung; Berquist, Brian R.; Sigurdson, Alice J.

    2010-01-01

    The major DNA repair pathway for coping with spontaneous forms of DNA damage, such as natural hydrolytic products or oxidative lesions, is base excision repair (BER). In particular, BER processes mutagenic and cytotoxic DNA lesions such as non-bulky base modifications, abasic sites, and a range of chemically distinct single-strand breaks. Defects in BER have been linked to cancer predisposition, neurodegenerative disorders, and immunodeficiency. Recent data indicate a large degree of sequence variability in DNA repair genes and several studies have associated BER gene polymorphisms with disease risk, including cancer of several sites. The intent of this review is to describe the range of BER capacity among individuals and the functional consequences of BER genetic variants. We also discuss studies that associate BER deficiency with disease risk and the current state of BER capacity measurement assays. PMID:21167187

  17. Macrophages in tissue repair, regeneration, and fibrosis

    PubMed Central

    Wynn, Thomas A.; Vannella, Kevin M.

    2016-01-01

    Inflammatory monocytes and resident tissue macrophages are key regulators of tissue repair, regeneration, and fibrosis. Following tissue injury, monocytes and macrophages undergo marked phenotypic and functional changes to play critical roles during the initiation, maintenance, and resolution phases of tissue repair. Disturbances in macrophage function can lead to aberrant repair, with uncontrolled inflammatory mediator and growth factor production, deficient generation of anti-inflammatory macrophages, or failed communication between macrophages and epithelial cells, endothelial cells, fibroblasts, and stem or tissue progenitor cells all contributing to a state of persistent injury, which may lead to the development of pathological fibrosis. In this review, we discuss the mechanisms that instruct macrophages to adopt pro-inflammatory, pro-wound healing, pro-fibrotic, anti-inflammatory, anti-fibrotic, pro-resolving, and tissue regenerating phenotypes following injury, and highlight how some of these mechanisms and macrophage activation states could be exploited therapeutically. PMID:26982353

  18. DNA Damage and Repair in Vascular Disease.

    PubMed

    Uryga, Anna; Gray, Kelly; Bennett, Martin

    2016-01-01

    DNA damage affecting both genomic and mitochondrial DNA is present in a variety of both inherited and acquired vascular diseases. Multiple cell types show persistent DNA damage and a range of lesions. In turn, DNA damage activates a variety of DNA repair mechanisms, many of which are activated in vascular disease. Such DNA repair mechanisms either stall the cell cycle to allow repair to occur or trigger apoptosis or cell senescence to prevent propagation of damaged DNA. Recent evidence has indicated that DNA damage occurs early, is progressive, and is sufficient to impair function of cells composing the vascular wall. The consequences of persistent genomic and mitochondrial DNA damage, including inflammation, cell senescence, and apoptosis, are present in vascular disease. DNA damage can thus directly cause vascular disease, opening up new possibilities for both prevention and treatment. We review the evidence for and the causes, types, and consequences of DNA damage in vascular disease.

  19. Animal Models for Cartilage Regeneration and Repair

    PubMed Central

    Szczodry, Michal; Bruno, Stephen

    2010-01-01

    Articular cartilage injury and degeneration are leading causes of disability. Animal studies are critically important to developing effective treatments for cartilage injuries. This review focuses on the use of animal models for the study of the repair and regeneration of focal cartilage defects. Animals commonly used in cartilage repair studies include murine, lapine, canine, caprine, porcine, and equine models. There are advantages and disadvantages to each model. Small animal rodent and lapine models are cost effective, easy to house, and useful for pilot and proof-of-concept studies. The availability of transgenic and knockout mice provide opportunities for mechanistic in vivo study. Athymic mice and rats are additionally useful for evaluating the cartilage repair potential of human cells and tissues. Their small joint size, thin cartilage, and greater potential for intrinsic healing than humans, however, limit the translational value of small animal models. Large animal models with thicker articular cartilage permit study of both partial thickness and full thickness chondral repair, as well as osteochondral repair. Joint size and cartilage thickness for canine, caprine, and mini-pig models remain significantly smaller than that of humans. The repair and regeneration of chondral and osteochondral defects of size and volume comparable to that of clinically significant human lesions can be reliably studied primarily in equine models. While larger animals may more closely approximate the human clinical situation, they carry greater logistical, financial, and ethical considerations. A multifactorial analysis of each animal model should be carried out when planning in vivo studies. Ultimately, the scientific goals of the study will be critical in determining the appropriate animal model. PMID:19831641

  20. Nerve Transfer in Delayed Obstetrical Palsy Repair

    PubMed Central

    Sénès, Filippo; Catena, Nunzio; Sénès, Jacopo

    2015-01-01

    Objective  When root avulsions are detected in children suffering from obstetrical brachial plexus palsy (OBPP), neurotization procedures of different nerve trunks are commonly applied in primary brachial plexus repair, to connect distally the nerves of the upper limbs using healthy nerve structures. This article aims to outline our experience of neurotization procedures in OBPP, which involves nerve transfers in the event of delayed repair, when a primary repair has not occurred or has failed. In addition, we propose the opportunity for late repair, focusing on extending the time limit for nerve surgery beyond that which is usually recommended. Although, according to different authors, the time limit is still unclear, it is generally estimated that nerve repair should take place within the first months of life. In fact, microsurgical repair of OBPP is the technique of choice for young children with the condition who would otherwise have an unfavorable outcome. However, in certain cases the recovery process is not clearly defined so not all the patients are direct candidates for primary nerve surgery. Methods  In the period spanning January 2005 through January 2011, among a group of 105 patients suffering from OBPP, ranging from 1 month to 7 years of age, the authors have identified a group of 32 partially recovered patients. All these patients underwent selective neurotization surgery, which was performed in a period ranging from 5 months to 6.6 years of age. Results  Late neurotization of muscular groups achieved considerable functional recovery in these patients, who presented with reduced motor function during early childhood. The said patients, with the exception of five, would initially have avoided surgery because they had not met the criteria for nerve surgery. Conclusion  We have concluded that the execution of late nerve surgical procedures can be effective in children affected by OBPP. PMID:27917233

  1. Global genome nucleotide excision repair is organized into domains that promote efficient DNA repair in chromatin

    PubMed Central

    Yu, Shirong; Evans, Katie; Bennett, Mark; Webster, Richard M.; Leadbitter, Matthew; Teng, Yumin; Waters, Raymond

    2016-01-01

    The rates at which lesions are removed by DNA repair can vary widely throughout the genome, with important implications for genomic stability. To study this, we measured the distribution of nucleotide excision repair (NER) rates for UV-induced lesions throughout the budding yeast genome. By plotting these repair rates in relation to genes and their associated flanking sequences, we reveal that, in normal cells, genomic repair rates display a distinctive pattern, suggesting that DNA repair is highly organized within the genome. Furthermore, by comparing genome-wide DNA repair rates in wild-type cells and cells defective in the global genome–NER (GG-NER) subpathway, we establish how this alters the distribution of NER rates throughout the genome. We also examined the genomic locations of GG-NER factor binding to chromatin before and after UV irradiation, revealing that GG-NER is organized and initiated from specific genomic locations. At these sites, chromatin occupancy of the histone acetyl-transferase Gcn5 is controlled by the GG-NER complex, which regulates histone H3 acetylation and chromatin structure, thereby promoting efficient DNA repair of UV-induced lesions. Chromatin remodeling during the GG-NER process is therefore organized into these genomic domains. Importantly, loss of Gcn5 significantly alters the genomic distribution of NER rates; this has implications for the effects of chromatin modifiers on the distribution of mutations that arise throughout the genome. PMID:27470111

  2. Nucleotide excision repair in Trypanosoma brucei: specialization of transcription-coupled repair due to multigenic transcription

    PubMed Central

    Machado, Carlos R; Vieira-da-Rocha, João P; Mendes, Isabela Cecilia; Rajão, Matheus A; Marcello, Lucio; Bitar, Mainá; Drummond, Marcela G; Grynberg, Priscila; Oliveira, Denise A A; Marques, Catarina; Van Houten, Ben; McCulloch, Richard

    2014-01-01

    Nucleotide excision repair (NER) is a highly conserved genome repair pathway acting on helix distorting DNA lesions. NER is divided into two subpathways: global genome NER (GG-NER), which is responsible for repair throughout genomes, and transcription-coupled NER (TC-NER), which acts on lesions that impede transcription. The extent of the Trypanosoma brucei genome that is transcribed is highly unusual, since most genes are organized in multigene transcription units, each transcribed from a single promoter. Given this transcription organization, we have addressed the importance of NER to T. brucei genome maintenance by performing RNAi against all predicted contributing factors. Our results indicate that TC-NER is the main pathway of NER repair, but only CSB, XPBz and XPG contribute. Moreover, we show that UV lesions are inefficiently repaired in T. brucei, perhaps due to preferential use of RNA polymerase translesion synthesis. RNAi of XPC and DDB was found to be lethal, and we show that these factors act in inter-strand cross-link repair. XPD and XPB appear only to act in transcription, not repair. This work indicates that the predominance of multigenic transcription in T. brucei has resulted in pronounced adaptation of NER relative to the host and may be an attractive drug target. PMID:24661334

  3. Epigenetic reduction of DNA repair in progression to gastrointestinal cancer

    PubMed Central

    Bernstein, Carol; Bernstein, Harris

    2015-01-01

    Deficiencies in DNA repair due to inherited germ-line mutations in DNA repair genes cause increased risk of gastrointestinal (GI) cancer. In sporadic GI cancers, mutations in DNA repair genes are relatively rare. However, epigenetic alterations that reduce expression of DNA repair genes are frequent in sporadic GI cancers. These epigenetic reductions are also found in field defects that give rise to cancers. Reduced DNA repair likely allows excessive DNA damages to accumulate in somatic cells. Then either inaccurate translesion synthesis past the un-repaired DNA damages or error-prone DNA repair can cause mutations. Erroneous DNA repair can also cause epigenetic alterations (i.e., epimutations, transmitted through multiple replication cycles). Some of these mutations and epimutations may cause progression to cancer. Thus, deficient or absent DNA repair is likely an important underlying cause of cancer. Whole genome sequencing of GI cancers show that between thousands to hundreds of thousands of mutations occur in these cancers. Epimutations that reduce DNA repair gene expression and occur early in progression to GI cancers are a likely source of this high genomic instability. Cancer cells deficient in DNA repair are more vulnerable than normal cells to inactivation by DNA damaging agents. Thus, some of the most clinically effective chemotherapeutic agents in cancer treatment are DNA damaging agents, and their effectiveness often depends on deficient DNA repair in cancer cells. Recently, at least 18 DNA repair proteins, each active in one of six DNA repair pathways, were found to be subject to epigenetic reduction of expression in GI cancers. Different DNA repair pathways repair different types of DNA damage. Evaluation of which DNA repair pathway(s) are deficient in particular types of GI cancer and/or particular patients may prove useful in guiding choice of therapeutic agents in cancer therapy. PMID:25987950

  4. Epigenetic reduction of DNA repair in progression to gastrointestinal cancer.

    PubMed

    Bernstein, Carol; Bernstein, Harris

    2015-05-15

    Deficiencies in DNA repair due to inherited germ-line mutations in DNA repair genes cause increased risk of gastrointestinal (GI) cancer. In sporadic GI cancers, mutations in DNA repair genes are relatively rare. However, epigenetic alterations that reduce expression of DNA repair genes are frequent in sporadic GI cancers. These epigenetic reductions are also found in field defects that give rise to cancers. Reduced DNA repair likely allows excessive DNA damages to accumulate in somatic cells. Then either inaccurate translesion synthesis past the un-repaired DNA damages or error-prone DNA repair can cause mutations. Erroneous DNA repair can also cause epigenetic alterations (i.e., epimutations, transmitted through multiple replication cycles). Some of these mutations and epimutations may cause progression to cancer. Thus, deficient or absent DNA repair is likely an important underlying cause of cancer. Whole genome sequencing of GI cancers show that between thousands to hundreds of thousands of mutations occur in these cancers. Epimutations that reduce DNA repair gene expression and occur early in progression to GI cancers are a likely source of this high genomic instability. Cancer cells deficient in DNA repair are more vulnerable than normal cells to inactivation by DNA damaging agents. Thus, some of the most clinically effective chemotherapeutic agents in cancer treatment are DNA damaging agents, and their effectiveness often depends on deficient DNA repair in cancer cells. Recently, at least 18 DNA repair proteins, each active in one of six DNA repair pathways, were found to be subject to epigenetic reduction of expression in GI cancers. Different DNA repair pathways repair different types of DNA damage. Evaluation of which DNA repair pathway(s) are deficient in particular types of GI cancer and/or particular patients may prove useful in guiding choice of therapeutic agents in cancer therapy.

  5. Acute flexor tendon repairs in zone II.

    PubMed

    Coats, Robert W; Echevarría-Oré, Julio C; Mass, Daniel P

    2005-05-01

    Flexor tendon repair in zone II is still a technically demanding procedure, but the outcomes have become more predictable and satisfying. Of keystone importance for obtaining the goals of normal strength and gliding of repaired flexor tendons are an atraumatic surgical technique, an appropriate suture material, a competent pulley system, and the use of early motion rehabilitation protocols. The overall goal of hand and finger function also implies timely addressing of neurovascular injuries. New devices such as the TenoFix (Ortheon Medical; Winter Park, Florida) have shown adequate strength in the laboratory but are bulky and untested for work of flexion. Insufficient clinical data and high cost may prevent widespread use.

  6. Method of repairing hidden leaks in tubes

    NASA Technical Reports Server (NTRS)

    Duesberg, J. D. (Inventor); Mills, R. C., Sr. (Inventor)

    1986-01-01

    A method of repairing a tubular assembly in which access to a defect in the tube is limited includes the steps of cutting an opening in the tube on the side opposite the defect so as to expose the defect from the inside of the tube. A tubular insert is inserted into the tube to cover the defect and is secured in place by means of brazing or welding. The remaining space between the opening and insert is closed by means of close-out patches which are welded or brazed to both the insert and the tube. The result is a permanent repair having great structural integrity.

  7. Aging processes, DNA damage, and repair.

    PubMed

    Gilchrest, B A; Bohr, V A

    1997-04-01

    The second triennial FASEB Summer Research Conference on "Clonal Senescence and Differentiation" (August 17-22, 1996) focused on the interrelationships between aging processes and DNA damage and repair. The attendees represented a cross section of senior and junior investigators working in fields ranging from classic cellular gerontology to yeast and nematode models of aging to basic mechanisms of DNA damage and repair. The meeting opened with a keynote address by Dr. Bruce Ames that emphasized the documented relationships between oxidative damage, cancer, and aging. This was followed by eight platform sessions, one poster discussion, one featured presentation, and an after-dinner address. The following sections highlight the key points discussed.

  8. The awakening of DNA repair at Yale.

    PubMed

    Hanawalt, Philip C

    2013-12-13

    As a graduate student with Professor Richard Setlow at Yale in the late 1950s, I studied the effects of ultraviolet and visible light on the syntheses of DNA, RNA, and protein in bacteria. I reflect upon my research in the Yale Biophysics Department, my subsequent postdoctoral experiences, and the eventual analyses in the laboratories of Setlow, Paul Howard-Flanders, and myself that constituted the discovery of the ubiquitous pathway of DNA excision repair in the early 1960s. I then offer a brief perspective on a few more recent developments in the burgeoning DNA repair field and their relationships to human disease.

  9. Prosthetic Mesh Repair for Incarcerated Inguinal Hernia

    PubMed Central

    Tatar, Cihad; Tüzün, İshak Sefa; Karşıdağ, Tamer; Kızılkaya, Mehmet Celal; Yılmaz, Erdem

    2016-01-01

    Background: Incarcerated inguinal hernia is a commonly encountered urgent surgical condition, and tension-free repair is a well-established method for the treatment of non-complicated cases. However, due to the risk of prosthetic material-related infections, the use of mesh in the repair of strangulated or incarcerated hernia has often been subject to debate. Recent studies have demonstrated that biomaterials represent suitable materials for performing urgent hernia repair. Certain studies recommend mesh repair only for cases where no bowel resection is required; other studies, however, recommend mesh repair for patients requiring bowel resection as well. Aim: The aim of this study was to compare the outcomes of different surgical techniques performed for strangulated hernia, and to evaluate the effect of mesh use on postoperative complications. Study Design: Retrospective cross-sectional study. Methods: This retrospective study was performed with 151 patients who had been admitted to our hospital’s emergency department to undergo surgery for a diagnosis of incarcerated inguinal hernia. The patients were divided into two groups based on the applied surgical technique. Group 1 consisted of 112 patients treated with mesh-based repair techniques, while Group 2 consisted of 39 patients treated with tissue repair techniques. Patients in Group 1 were further divided into two sub-groups: one consisting of patients undergoing bowel resection (Group 3), and the other consisting of patients not undergoing bowel resection (Group 4). Results: In Group 1, it was observed that eight (7.14%) of the patients had wound infections, while two (1.78%) had hematomas, four (3.57%) had seromas, and one (0.89%) had relapse. In Group 2, one (2.56%) of the patients had a wound infection, while three (7.69%) had hematomas, one (2.56%) had seroma, and none had relapses. There were no statistically significant differences between the two groups with respect to wound infection, seroma

  10. Generic and Automated Runtime Program Repair

    DTIC Science & Technology

    2012-09-01

    out using 15% of the memory and 5% of the disk space of pre-award work, and concrete examples of repairs using Nokia N900 smartphones are described...red. Experiments were run either on a machine with 2.2 GHz AMD Opteron processors and 120 GB of memory or on Nokia N900 smartphones, each of which...the memory usage when performing repairs for each combination of program and representation. Our Nokia smartphones have 256+768 MB of RAM plus swap. In

  11. Repairable chip bonding/interconnect process

    DOEpatents

    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.

  12. Repairable chip bonding/interconnect process

    DOEpatents

    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.

  13. Summary of Repair Techniques for Aluminum Bridging.

    DTIC Science & Technology

    1982-10-01

    OCT 82 CERL-TR-M-324 UNCLASSIFIED F/G 13/8 NL mEEEimuinuIEEBI-EEIIIIIE 111-2 11112.2~ 111L25 nu 111I. M RO f PIHULL]TIN 7[ ..k contrutio of Enginrs ...aluminum bridging. A literature search was conducted to identify the various aluminum repair processes available. The merits of each method as a field...Army C’onsfruclion EnPrincering Restarch A literature search was conducted to assess various L.a jratorv I(’I.RIl, 1I’P. welding and joining repair

  14. Laser weld repair of tantalum sheet

    SciTech Connect

    Oldani, J.J.; Westrich, C.N.

    1992-12-01

    Tantalum sheets which are used in radiographic film cassettes for high explosives studies were repaired using Nd:YAG laser welding. The tantalum sheets can receive various levels of indentations and/or scratches which can leave radiographic indications during use in subsequent studies. Laser welding using a Raytheon 400 watt Nd:YAG laser and a 0.010 inch diameter tantalum filler wire with argon cover gas was used to fill in these false indications. A successful weld repair is required to give no radiographic indications, neither high nor low density readings.

  15. The Awakening of DNA Repair at Yale

    PubMed Central

    Hanawalt, Philip C.

    2013-01-01

    As a graduate student with Professor Richard Setlow at Yale in the late 1950s, I studied the effects of ultraviolet and visible light on the syntheses of DNA, RNA, and protein in bacteria. I reflect upon my research in the Yale Biophysics Department, my subsequent postdoctoral experiences, and the eventual analyses in the laboratories of Setlow, Paul Howard-Flanders, and myself that constituted the discovery of the ubiquitous pathway of DNA excision repair in the early 1960s. I then offer a brief perspective on a few more recent developments in the burgeoning DNA repair field and their relationships to human disease. PMID:24348216

  16. Lightweight Material Patches Allow for Quick Repairs

    NASA Technical Reports Server (NTRS)

    2010-01-01

    Cornerstone Research Group Inc., of Dayton, Ohio, has been the recipient of 16 Small Business Innovation Research (SBIR) contracts with NASA with a variety of different focuses, including projects like creating inflatable structures for radio frequency antennas and, most recently, healable polymer matrix composites for future space vehicles. One of its earlier SBIR contracts, with Kennedy Space Center, led to the development of a new type of structural patch for a variety of consumer uses: Rubbn Repair, for automotive uses; and Rec Repair for the outdoors and adventure market. Both are flexible, heat-activated structural patches.

  17. Space Habitat, assembly and repair facility

    NASA Technical Reports Server (NTRS)

    Colangelo, Todd A.; Hoetger, Debora C.; Kuo, Addison C.; Lo, Michael C.; Marcus, Leland R.; Tran, Phillip P.; Tutt, Chris J.; Wassmuth, Chad M.; Wildgrube, Gregory M.

    1992-01-01

    Integrated Space Systems (ISS) has designed a Low Earth Orbit Assembly Facility for submission in the 1992 AIAA/LORAL Team Space Design Competition. This facility, the Space Habitat, Assembly, and Repair Center (SHARC), will be used to construct, assemble, and service space vehicles. SHARC's primary mission will be the construction of interplanetary vehicles, but it will also be able to perform repair and refueling operations of craft which are in an Earth orbit. This facility has been designed using only present and near-present technology. The emphasis is on minimizing cost.

  18. Surgical Repair of Huge Left Ventricular Pseudoaneurysm After Sutureless Repair of Free Wall Rupture.

    PubMed

    Díez-Villanueva, Pablo; Sarraj, Anas; Navarrete, Gonzalo; Salamanca, Jorge; Pozo, Eduardo; Reyes, Guillermo; Alfonso, Fernando

    2017-02-01

    Left ventricular pseudoaneurysm (LVPsA) is a rare complication after sutureless patch repair of left ventricular free wall rupture (LVFWR), with few cases reported in the literature so far. We present the case of a young patient who early developed a huge LVPsA and moderate mitral regurgitation after sutureless patch repair for LVFWR after undergoing a successful Dor procedure using the "triple empanada patch technique" to exclude the LVPsA, remodel the left ventricle, and address the moderate mitral regurgitation. Serial echocardiograms during follow-up are strongly recommended, even in patients with successful patch repair, to facilitate timely diagnosis and management.

  19. 49 CFR 192.245 - Repair or removal of defects.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... that is repaired must have the defect removed down to sound metal and the segment to be repaired must... minimum mechanical properties specified for the welding procedure used to make the original weld are...

  20. 1. Lowlevel birdseye view looking SW at the Savannah Repair ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Low-level birdseye view looking SW at the Savannah Repair Shops. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  1. Situation-dependent repair of DNA damage in yeast

    SciTech Connect

    von Borstel, R.C.; Hastings, P.J.

    1985-01-01

    The concept of channelling of lesions in DNA into defined repair systems has been used to explain many aspects of induced and spontaneous mutation. The channelling hypothesis states that lesions excluded from one repair process will be taken up by another repair process. This is a simplification. The three known modes of repair of damage induced by radiation are not equivalent modes of repair; they are, instead, different solutions to the problem of replacement of damaged molecules with new molecules which have the same informational content as those that were damaged. The mode of repair that is used is the result of the response to the situation in which the damage takes place. Thus, when the most likely mode of repair does not take place, then the situation changes with respect to the repair of the lesion; the lesion may enter the replication fork and be reparable by another route.

  2. Databases and Bioinformatics Tools for the Study of DNA Repair

    PubMed Central

    Milanowska, Kaja; Rother, Kristian; Bujnicki, Janusz M.

    2011-01-01

    DNA is continuously exposed to many different damaging agents such as environmental chemicals, UV light, ionizing radiation, and reactive cellular metabolites. DNA lesions can result in different phenotypical consequences ranging from a number of diseases, including cancer, to cellular malfunction, cell death, or aging. To counteract the deleterious effects of DNA damage, cells have developed various repair systems, including biochemical pathways responsible for the removal of single-strand lesions such as base excision repair (BER) and nucleotide excision repair (NER) or specialized polymerases temporarily taking over lesion-arrested DNA polymerases during the S phase in translesion synthesis (TLS). There are also other mechanisms of DNA repair such as homologous recombination repair (HRR), nonhomologous end-joining repair (NHEJ), or DNA damage response system (DDR). This paper reviews bioinformatics resources specialized in disseminating information about DNA repair pathways, proteins involved in repair mechanisms, damaging agents, and DNA lesions. PMID:22091405

  3. 49 CFR 192.245 - Repair or removal of defects.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Welding of Steel in Pipelines § 192... that is repaired must have the defect removed down to sound metal and the segment to be repaired...

  4. Composite Structures Repair Development at Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Cox, Sarah B.

    2015-01-01

    This presentation discusses the development and results of composite patch repair perfromed at Kennedy Space Center. This includes impact damage, patch repair methods, nondestructive evaluation, and edgewise compression testing.

  5. View of automotive repair and gas station, facing southwest from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of automotive repair and gas station, facing southwest from across Pope Street. Garage built for storage of employee automobiles in left background - Automotive Repair & Gas Station, Southwest corner of Pope Street & Olympic Avenue, Port Gamble, Kitsap County, WA

  6. View of south elevation of Automotive and Tractor Repair Shops ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of south elevation of Automotive and Tractor Repair Shops with the Warehouse Fabrication Shop and Stack in the background, looking from the southwest - Kekaha Sugar Company, Automotive and Tractor Repair Shops, 8315 Kekaha Road, Kekaha, Kauai County, HI

  7. 21 CFR 872.3570 - OTC denture repair kit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3570 OTC denture repair kit. (a) Identification. An OTC denture repair kit is a device consisting of a material, such as a resin monomer system...

  8. Nucleotide excision repair of DNA: The very early history.

    PubMed

    Friedberg, Errol C

    2011-07-15

    This article, taken largely from the book Correcting the Blueprint of Life: An Historical Account of the Discovery of DNA Repair Mechanisms, summarizes the very early history of the discovery of nucleotide excision repair.

  9. 24. Moody Bridge truss repair plans showing existing area of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Moody Bridge truss repair plans showing existing area of damage along with repair procedures for correcting damage and returning truss to structural integrity. - Moody Bridge, Spanning South Fork Eel River, Garberville, Humboldt County, CA

  10. Compressive strength of damaged and repaired composite plates

    NASA Technical Reports Server (NTRS)

    Finn, Scott R.; Springer, George S.

    1992-01-01

    Tests were performed assessing the effectiveness of repair in restoring the mechanical properties of damaged, solid composite plates made of Fiberite T300/976 graphite-epoxy. Some (75%) or all (100%) of the damaged zone was cut out, and the plate was repaired by plugging and patching the hole. The effectiveness of the repair was evaluated by measuring the compressive strengths of undamaged plates, damaged plates with no cutout, damaged plates with a cutout, and plates that had been repaired.

  11. Finite element analysis to model complex mitral valve repair.

    PubMed

    Labrosse, Michel; Mesana, Thierry; Baxter, Ian; Chan, Vincent

    2016-01-01

    Although finite element analysis has been used to model simple mitral repair, it has not been used to model complex repair. A virtual mitral valve model was successful in simulating normal and abnormal valve function. Models were then developed to simulate an edge-to-edge repair and repair employing quadrangular resection. Stress contour plots demonstrated increased stresses along the mitral annulus, corresponding to the annuloplasty. The role of finite element analysis in guiding clinical practice remains undetermined.

  12. Radio and Television Repairer Fundamentals. Student's Manual.

    ERIC Educational Resources Information Center

    Maul, Chuck

    This self-contained student manual on fundamentals of radio and television repair is designed to help trade and industrial students relate work experience on the job to information studied at school. Designed for individualized instruction under the supervision of a coordinator or instructor, the manual has 9 sections, each containing 2 to 10…

  13. Method for mask repair using defect compensation

    DOEpatents

    Sweeney, Donald W.; Ray-Chaudhuri, Avijit K.

    2001-01-01

    A method for repair of amplitude and/or phase defects in lithographic masks. The method involves modifying or altering a portion of the absorber pattern on the surface of the mask blank proximate to the mask defect to compensate for the local disturbance (amplitude or phase) of the optical field due to the defect.

  14. Repair Negotiation by English L2 Learners

    ERIC Educational Resources Information Center

    Choi, Yujeong

    2012-01-01

    It is widely accepted that L2 learners often face communication problems due to lack of competency in the target language and familiarity with its culture of origin. One way to resolve miscommunication problems is to seek clarification of the utterance; this process is called "repair negotiation" (Nakahama et al. 2001). Repair…

  15. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., “Flammable and Combustible Liquids Code”; American Petroleum Institute Publication 2200, “Repairing Crude Oil, Liquified Petroleum Gas, and Product Pipelines”; American Petroleum Institute Publication 1631, “Recommended... Association Standard 631, “Spill Prevention, Minimum 10 Year Life Extension of Existing Steel...

  16. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., “Flammable and Combustible Liquids Code”; American Petroleum Institute Publication 2200, “Repairing Crude Oil, Liquified Petroleum Gas, and Product Pipelines”; American Petroleum Institute Publication 1631, “Recommended... Association Standard 631, “Spill Prevention, Minimum 10 Year Life Extension of Existing Steel...

  17. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., “Flammable and Combustible Liquids Code”; American Petroleum Institute Publication 2200, “Repairing Crude Oil, Liquified Petroleum Gas, and Product Pipelines”; American Petroleum Institute Publication 1631, “Recommended... Association Standard 631, “Spill Prevention, Minimum 10 Year Life Extension of Existing Steel...

  18. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., “Flammable and Combustible Liquids Code”; American Petroleum Institute Publication 2200, “Repairing Crude Oil, Liquified Petroleum Gas, and Product Pipelines”; American Petroleum Institute Publication 1631, “Recommended... Association Standard 631, “Spill Prevention, Minimum 10 Year Life Extension of Existing Steel...

  19. 40 CFR 280.33 - Repairs allowed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., “Flammable and Combustible Liquids Code”; American Petroleum Institute Publication 2200, “Repairing Crude Oil, Liquified Petroleum Gas, and Product Pipelines”; American Petroleum Institute Publication 1631, “Recommended... Association Standard 631, “Spill Prevention, Minimum 10 Year Life Extension of Existing Steel...

  20. New Technology in Automotive Body Repair.

    ERIC Educational Resources Information Center

    Maze, Ronald W.

    1980-01-01

    The use of plastic and fiberglass materials in the manufacture of automobiles has caused a revolution in the field of collision work. Changes have occurred in tools, techniques, materials, and in the training for auto body repair. The skills necessary for employment in this field are now easier and faster to acquire. (CT)

  1. Amoco Trinidad selects wet welding repair option

    SciTech Connect

    Ibarra, S.J.; Reynolds, T.J.; Gabriel, V.; Haymaker, G.A.

    1996-12-01

    A recent underwater inspection of Amoco Trinidad Oil Company`s Samaan A Production platform revealed a separated horizontal brace at a water depth of 125 feet (38.1 m). A closer inspection showed that the 16 in (.4 m) diameter horizontal brace had completely separated from the Leg on the member side. A drilling program scheduled to commence from the Samaan A platform was to begin in about two months. A fast track analysis of the structure and a subsequent repair plan was immediately organized. A computer aided structural analysis was completed for the structure with the horizontal brace removed. Structural engineers decided that the brace must be reinstalled before being loaded with a drilling unit. A clamped brace repair assembly was not practical due to a multi member node at one of the legs. Wet welding was selected over dry hyperbaric welding as the best, safest, most cost effective and quickest option. A wet welding procedure and welder divers were qualified at depth according to AWS D3.6. A repair assembly was designed and fabricated. Personnel, wet welding equipment and the fabrication were shipped by air from New Iberia, LA to Galeota Point, Trinidad. This is the first time that wet welding techniques were employed for structural repairs directly to the leg of an offshore structure at any Amoco location.

  2. CERAMIC RESTORATION REPAIR: REPORT OF TWO CASES

    PubMed Central

    Raposo, Luís Henrique Araújo; Neiva, Natália Antunes; da Silva, Gisele Rodrigues; Carlo, Hugo Lemes; da Mota, Adérito Soares; do Prado, Célio Jesus; Soares, Carlos José

    2009-01-01

    The esthetic and functional rehabilitation of patients with multiple missing teeth can be performed with several techniques and materials. Ceramic restorations provide reliable masticatory function and good esthetics. However, fracture can occur in some cases due to their brittle behavior. In some cases, the replacement of an extensive prosthesis is a problem due to the high treatment cost. In this paper, two cases are presented, in which fractures occurred in extensive metal-ceramic fixed partial dentures, and their replacement was not possible. Ceramic repair was chosen and the sequences of treatment with and without presence of the ceramic fragment are also discussed. The cases illustrate that, in some situations, fractured metal-ceramic partial dentures can be successfully repaired when prosthetic replacement is not a choice. Prosthodontists must use alternatives that allow a reliable repair to extensive metal-ceramic fixed partial dentures. Surface preparation of the ceramic with hydrofluoric acid in conjunction with a silane coupling agent is essential for a predictable bonding of composite resin. The repair performed with composite resin is an esthetic and functional alternative when extensive fixed partial dentures cannot be replaced. PMID:19274401

  3. Cockayne syndrome: defective repair of transcription?

    PubMed Central

    van Gool, A J; van der Horst, G T; Citterio, E; Hoeijmakers, J H

    1997-01-01

    In the past years, it has become increasingly evident that basal metabolic processes within the cell are intimately linked and influenced by one another. One such link that recently has attracted much attention is the close interplay between nucleotide excision DNA repair and transcription. This is illustrated both by the preferential repair of the transcribed strand of active genes (a phenomenon known as transcription-coupled repair, TCR) as well as by the distinct dual involvement of proteins in both processes. The mechanism of TCR in eukaryotes is still largely unknown. It was first discovered in mammals by the pioneering studies of Hanawalt and colleagues, and subsequently identified in yeast and Escherichia coli. In the latter case, one protein, the transcription repair-coupling factor, was found to accomplish this function in vitro, and a plausible model for its activity was proposed. While the E. coli model still functions as a paradigm for TCR in eukaryotes, recent observations prompt us to believe that the situation in eukaryotes is much more complex, involving dual functionality of multiple proteins. PMID:9250659

  4. Day-case laparoscopic hernia repair.

    PubMed

    Evans, D S; Ghaneh, P; Khan, I M

    1996-10-01

    Some 114 patients (median age 52 years) underwent laparoscopic hernia repair as a day-case procedure. Twenty-one patients had bilateral and 11 recurrent hernias. Some 113 patients underwent transabdominal preperitoneal mesh repair but one required conversion to open operation. Mean operating time was 24 min for unilateral and 38 min for bilateral repair. In an operating session of 3.5 h, up to five patients (mean 4.4) underwent surgery and as many as seven hernias were repaired. More than 10 per cent of patients were found to have a previously undiagnosed hernia on the opposite side. A total of 111 patients were discharged home on the day of surgery. Major complications included one omental bleed and one small bowel obstruction. Seroma was the commonest minor complication and occurred in 7 per cent of patients. More than 35 per cent of patients needed no postoperative analgesia. To date there has been one recurrence (follow-up range 2-18 months).

  5. Auto Body Repair Curriculum. Instructor's Guide.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Instructional Materials Lab.

    This teacher's guide to the Missouri auto body repair curriculum contains seven modules of instruction. Within each module are instructional units including some or all of the following components: performance objectives, information sheets, handouts, transparency masters, assignment sheets, job sheets, a unit test, and answers to the unit test.…

  6. DNA Damage, DNA Repair, Aging, and Neurodegeneration.

    PubMed

    Maynard, Scott; Fang, Evandro Fei; Scheibye-Knudsen, Morten; Croteau, Deborah L; Bohr, Vilhelm A

    2015-09-18

    Aging in mammals is accompanied by a progressive atrophy of tissues and organs, and stochastic damage accumulation to the macromolecules DNA, RNA, proteins, and lipids. The sequence of the human genome represents our genetic blueprint, and accumulating evidence suggests that loss of genomic maintenance may causally contribute to aging. Distinct evidence for a role of imperfect DNA repair in aging is that several premature aging syndromes have underlying genetic DNA repair defects. Accumulation of DNA damage may be particularly prevalent in the central nervous system owing to the low DNA repair capacity in postmitotic brain tissue. It is generally believed that the cumulative effects of the deleterious changes that occur in aging, mostly after the reproductive phase, contribute to species-specific rates of aging. In addition to nuclear DNA damage contributions to aging, there is also abundant evidence for a causative link between mitochondrial DNA damage and the major phenotypes associated with aging. Understanding the mechanistic basis for the association of DNA damage and DNA repair with aging and age-related diseases, such as neurodegeneration, would give insight into contravening age-related diseases and promoting a healthy life span.

  7. Flavonoids and DNA Repair in Prostate Cancer

    DTIC Science & Technology

    2004-12-01

    responsible to fill the gap created by the excision of 8-OHdG. There is in vitro evidence that some flavonoids such as myricetin and baicalin will...myricetin. Methods Enzymol., 335, 308-316. 4. Chen,X., Nishida,H., and Konishi,T. (2003) Baicalin promoted the repair of DNA single strand breakage caused by

  8. 40 CFR 65.105 - Leak repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... assembly supplies have been depleted, and valve assembly supplies had been sufficiently stocked before the supplies were depleted. Delay of repair beyond the second process unit shutdown will not be allowed unless... may be included as part of the startup/shutdown/malfunction plan required by § 65.6 for the source...

  9. Repairing A Shaft Prone To Fatigue

    NASA Technical Reports Server (NTRS)

    Sharp, Roger A.; Larsen, David V.; Bates, Garold A.

    1991-01-01

    Shaft of hydraulic motor now outlives its bearings. Procedure for repairing John Deere Series 50 (or equivalent) hydraulic motor solves problem posed by common type of fatigue failure of shaft. Includes forming internally threaded hole in end of shaft, inserting double-threaded end stud, and adding washers and collars.

  10. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., if the bridge is a legally approved structure, be made as routine maintenance without approval of the... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES...

  11. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., if the bridge is a legally approved structure, be made as routine maintenance without a formal permit... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES...

  12. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., if the bridge is a legally approved structure, be made as routine maintenance without a formal permit... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES...

  13. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., if the bridge is a legally approved structure, be made as routine maintenance without a formal permit... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES...

  14. 33 CFR 115.40 - Bridge repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., if the bridge is a legally approved structure, be made as routine maintenance without approval of the... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bridge repairs. 115.40 Section 115.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES...

  15. Cyclic Linearization and Island Repair in Sluicing

    ERIC Educational Resources Information Center

    Qiu, Chunan

    2009-01-01

    Cyclic Linearization is adopted to account for the island repair of Sluicing in English. The extraction of wh-phrase out of certain islands undergoes non-successive-cyclic movement, which yields conflicting ordering statements. The derivation can be rescued by deleting all ordering statements in IP, including those conflicting ones. Two arguments…

  16. Auto Body Repair 103, 203, 303.

    ERIC Educational Resources Information Center

    Manitoba Dept. of Education, Winnipeg.

    As part of the high school vocational industrial program in Manitoba, this course has been designed to provide students with the foundation for a career in auto-body repair. The program introduces and provides opportunities for student skill development in the theories and techniques of tool and equipment operation, metallurgy and welding, damage…

  17. Computer Equipment Repair Test Item Bank.

    ERIC Educational Resources Information Center

    Reneau, Fred; And Others

    This guide contains 321 test items for use in teaching a course in repairing computer equipment. All test items were reviewed, revised, and validated by incumbent workers and subject matter instructors. Items are provided for assessing student achievement in the following skill areas (with selected skills mentioned in brackets): performing…

  18. Spinal Cord Repair with Engineered Nervous Tissue

    DTIC Science & Technology

    2014-04-01

    in order to minimize scarring and injected dissociated adult DRGs rostral to a dorsal column transection of the spinal cord. From the sensory... columns were dissected and post-fixed overnight in 4% paraformaldehyde, and then spinal cords were dissected from spinal columns and cryoprotected...AD______________ Award Number: W81XWH-10-1-0941 TITLE: Spinal Cord Repair with Engineered Nervous Tissue

  19. Weightbearing Versus Nonweightbearing After Meniscus Repair

    PubMed Central

    VanderHave, Kelly L.; Perkins, Crystal; Le, Michael

    2015-01-01

    Context: Optimal rehabilitation after meniscal repair remains controversial. Objective: To review the current literature on weightbearing status after meniscal repairs and to provide evidence-based recommendations for postoperative rehabilitation. Data Sources: MEDLINE (January 1, 1993 to July 1, 2014) and Embase (January 1, 1993 to July 1, 2014) were queried with use of the terms meniscus OR/AND repair AND rehabilitation. Study Selection: Included studies were those with levels of evidence 1 through 4, with minimum 2 years follow-up and in an English publication. Study Design: Systematic review. Level of Evidence: Level 4. Data Extraction: Demographics and clinical and radiographic outcomes of meniscus repair at a minimum of 2 years follow-up were extracted. Results: Successful clinical outcomes ranged from 70% to 94% with conservative rehabilitation. More recent studies using an accelerated rehabilitation protocol with full weightbearing and early range of motion reported 64% to 96% good results. Conclusion: Outcomes after both conservative (restricted weightbearing) protocols and accelerated rehabilitation (immediate weightbearing) yielded similar good to excellent results; however, lack of similar objective criteria and consistency among surgical techniques and existing studies makes direct comparison difficult. PMID:26502413

  20. 49 CFR 195.422 - Pipeline repairs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pipeline repairs. 195.422 Section 195.422 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS...

  1. 49 CFR 195.422 - Pipeline repairs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pipeline repairs. 195.422 Section 195.422 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS...

  2. 49 CFR 195.422 - Pipeline repairs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Pipeline repairs. 195.422 Section 195.422 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS...

  3. 49 CFR 195.422 - Pipeline repairs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pipeline repairs. 195.422 Section 195.422 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS...

  4. 49 CFR 195.422 - Pipeline repairs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pipeline repairs. 195.422 Section 195.422 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS...

  5. Consumer Electronic Repair. Florida Vocational Program Guide.

    ERIC Educational Resources Information Center

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    This program guide identifies primary concerns in the organization, operation, and evaluation of a consumer electronic (radio and television) repair program. It is designed for local school district and community college administrators, instructors, program advisory committees, and regional coordinating councils. The guide begins with the…

  6. Antibody specific for a DNA repair protein

    DOEpatents

    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.

  7. DNA encoding a DNA repair protein

    DOEpatents

    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.

  8. 49 CFR 193.2617 - Repairs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Repairs. 193.2617 Section 193.2617 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY LIQUEFIED NATURAL GAS...

  9. Repairing Hidden Cracks in Coolant Tubes

    NASA Technical Reports Server (NTRS)

    Mills, R. C., Sr.; Duesberg, J.

    1984-01-01

    Repair technique closes leaks in tubes or conduits where access limited to wall opposite crack. Technique applicable to any tubular assembly where tubes bundled together or bonded to supporting shell, such as in heat exchangers. Procedure provides structural support to area failed and uninterrupted flow without significantly altering heat-transfer profile.

  10. Laparoscopic repair of adult Bochdalek's hernia

    PubMed Central

    Husain, Musharraf; Hajini, Firdoos Farooq; Ganguly, Pavitra; Bukhari, Syed

    2013-01-01

    Bochdalek's hernia is a type of congenital diaphragmatic hernia occurring in approximately 1 in 2200–12 500 live births. It is considered to be extremely rare in adults and poses a diagnostic challenge. We present a case of a young man who was diagnosed as a case of congenital Bochdalek's hernia and underwent laparoscopic mesh repair. PMID:23761496

  11. Thoracoabdominal aortic aneurysm repair: current endovascular perspectives

    PubMed Central

    Orr, Nathan; Minion, David; Bobadilla, Joseph L

    2014-01-01

    Thoracoabdominal aneurysms account for roughly 3% of identified aneurysms annually in the United States. Advancements in endovascular techniques and devices have broadened their application to these complex surgical problems. This paper will focus on the current state of endovascular thoracoabdominal aneurysm repair, including specific considerations in patient selection, operative planning, and perioperative complications. Both total endovascular and hybrid options will be considered. PMID:25170271

  12. Automotive Body Repair. Performance Objectives. Intermediate Course.

    ERIC Educational Resources Information Center

    Lang, Thomas

    Several intermediate performance objectives and corresponding criterion measures are listed for each of 10 terminal objectives for an intermediate automotive body repair and refinishing course. The materials were developed for a two-semester (3 hours daily) course for specialized classrooms, shop, and practical experiences designed to enable the…

  13. Regulation of DNA repair by parkin

    SciTech Connect

    Kao, Shyan-Yuan

    2009-05-01

    Mutation of parkin is one of the most prevalent causes of autosomal recessive Parkinson's disease (PD). Parkin is an E3 ubiquitin ligase that acts on a variety of substrates, resulting in polyubiquitination and degradation by the proteasome or monoubiquitination and regulation of biological activity. However, the cellular functions of parkin that relate to its pathological involvement in PD are not well understood. Here we show that parkin is essential for optimal repair of DNA damage. Parkin-deficient cells exhibit reduced DNA excision repair that can be restored by transfection of wild-type parkin, but not by transfection of a pathological parkin mutant. Parkin also protects against DNA damage-induced cell death, an activity that is largely lost in the pathological mutant. Moreover, parkin interacts with the proliferating cell nuclear antigen (PCNA), a protein that coordinates DNA excision repair. These results suggest that parkin promotes DNA repair and protects against genotoxicity, and implicate DNA damage as a potential pathogenic mechanism in PD.

  14. Automotive Body Repair. Performance Objectives. Basic Course.

    ERIC Educational Resources Information Center

    Lang, Thomas

    Several intermediate performance objectives and corresponding criterion measures are listed for each of 15 terminal objectives for a basic automotive body repair and refinishing course. The materials were developed for a two-semester (2 hours daily) course for organized classroom and shop experiences designed to enable the student to develop…

  15. Autologous blood products in rotator cuff repair.

    PubMed

    Mei-Dan, Omer; Carmont, Michael R

    2012-01-01

    We review the management of rotator cuff tears, the mechanism of action of autologous blood products, principally platelet-rich plasma, and the current evidence for effective use of platelet-rich plasma, particularly in relation to the shoulder and chronic rotator cuff tears, for biological augmentation of rotator cuff repair.

  16. Actin crosslinkers: repairing the sense of touch.

    PubMed

    Sun, Sean X; Walcott, Sam

    2010-10-26

    Cells use actin bundles infused with myosin to exert contractile forces on the extracellular environment. This active tension is essential for cellular mechanosensation. Now, the role of actin crosslinkers in stabilizing and repairing the actin bundles is coming into clearer view.

  17. Glenn Refractory Adhesive for Bonding and Exterior Repair (GRABER) Developed for Repairing Shuttle Damage

    NASA Technical Reports Server (NTRS)

    Singh, Mrityunjay; Shpargel, Tarah P.

    2005-01-01

    Advanced in-space repair technologies for reinforced carbon/carbon composite (RCC) thermal protection system (TPS) structures are critically needed for the space shuttle Return To Flight (RTF) efforts. These technologies are also critical for the repair and refurbishment of thermal protection system structures of future Crew Exploration Vehicles of space exploration programs. The Glenn Refractory Adhesive for Bonding and Exterior Repair (GRABER) material developed at the NASA Glenn Research Center has demonstrated capabilities for repair of small cracks and damage in RCC leading-edge material. The concept consists of preparing an adhesive paste of desired ceramic in a polymer/phenolic resin matrix with appropriate additives, such as surfactants, and then applying the paste into the damaged or cracked area of the RCC composite components with caulking guns. The adhesive paste cures at 100 to 120 C and transforms into a high-temperature ceramic during simulated vehicle reentry testing conditions.

  18. Percutaneous mitral valve repair for mitral regurgitation.

    PubMed

    Block, Peter C

    2003-02-01

    Mitral regurgitation (MR) associated with, ischemic, and degenerative (prolapse) disease, contributes to left ventricular (LV) dysfunction due to remodeling, and LV dilation, resulting in worsening of MR. Mitral valve (MV) surgical repair has provided improvement in survival, LV function and symptoms, especially when performed early. Surgical repair is complex, due to diverse etiologies and has significant complications. The Society for Thoracic Surgery database shows that operative mortality for a 1st repair is 2% and for re-do repair is 4 times that. Cardiopulmonary bypass and cardiac arrest are required. The attendant morbidity prolongs hospitalization and recovery. Alfieri simplified mitral repair using an edge-to-edge technique which subsequently has been shown to be effective for multiple etiologies of MR. The MV leaflers are typically brought together by a central suture producing a double orifice MV without stenosis. Umana reported that MR decreased from grade 3.6 +/- 0.5 to 0.8 +/- 0.4 (P < 0.0001) and LV ejection fraction increased from 33 +/- 13% to 45 +/- 11% (P = 0.0156). In 121 patients, Maisano reported freedom from re-operation of 95 +/- 4.8% with up to 6 year follow-up. Oz developed a MV "grasper" that is directly placed via a left ventriculotomy and coapts both leaflets which are then fastened by a graduated spiral screw. An in-vitro model using explanted human valves showed significant reduction in MR and in canine studies, animals followed by serial echo had persistent MV coaptation. At 12 weeks the device was endothelialized. These promising results have paved the way for a percutaneous or minimally invasive-off pump mitral repair. Evalve has developed catheter-based technology, which, by apposing the edges of a regurgitant MV, results in edge-to-edge repair. Release of the device is done after echo and fluoroscopic evaluation under normal loading conditions. If the desired effect is not produced the device can be repositioned or retrieved

  19. Component Repair Times Obtained from MSPI Data

    SciTech Connect

    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

  20. Hard Talk About Hardware: The Care and Repair of Equipment.

    ERIC Educational Resources Information Center

    Farmer, Lesley S. J.

    1996-01-01

    Outlines minor repairs and maintenance that can be done to minimize problems and to lower service costs for computers. Highlights include: components of a repair tool kit; benefits of familiarity with equipment; preventative measures to cut down on repairs; installation of RAM, DIP, and SIMM chips; board configurations; installation of a drive;…

  1. 14 CFR 145.209 - Repair station manual contents.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Repair station manual contents. 145.209... manual contents. A certificated repair station's manual must include the following: (a) An organizational chart identifying— (1) Each management position with authority to act on behalf of the repair...

  2. 30 CFR 75.510 - Energized trolley wires; repair.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Energized trolley wires; repair. 75.510 Section 75.510 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Energized trolley wires; repair. Energized trolley wires may be repaired only by a person trained to...

  3. 30 CFR 75.510 - Energized trolley wires; repair.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Energized trolley wires; repair. 75.510 Section 75.510 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Energized trolley wires; repair. Energized trolley wires may be repaired only by a person trained to...

  4. 30 CFR 75.510 - Energized trolley wires; repair.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Energized trolley wires; repair. 75.510 Section 75.510 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Energized trolley wires; repair. Energized trolley wires may be repaired only by a person trained to...

  5. 30 CFR 75.510 - Energized trolley wires; repair.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Energized trolley wires; repair. 75.510 Section 75.510 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Energized trolley wires; repair. Energized trolley wires may be repaired only by a person trained to...

  6. 30 CFR 75.510 - Energized trolley wires; repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Energized trolley wires; repair. 75.510 Section 75.510 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY... Energized trolley wires; repair. Energized trolley wires may be repaired only by a person trained to...

  7. 46 CFR 110.01-3 - Repairs and alterations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Repairs and alterations. 110.01-3 Section 110.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Applicability § 110.01-3 Repairs and alterations. (a) Repairs and replacements in kind must comply with...

  8. 46 CFR 110.01-3 - Repairs and alterations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Repairs and alterations. 110.01-3 Section 110.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Applicability § 110.01-3 Repairs and alterations. (a) Repairs and replacements in kind must comply with...

  9. 75 FR 11734 - Damage Tolerance Data for Repairs and Alterations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... TRANSPORTATION Federal Aviation Administration 14 CFR Part 26 RIN 2120-AI32 Damage Tolerance Data for Repairs and... make damage tolerance data for repairs and alterations to fatigue critical airplane structure available... of design approvals to make available to operators damage tolerance (DT) data for repairs...

  10. 46 CFR 110.01-3 - Repairs and alterations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Repairs and alterations. 110.01-3 Section 110.01-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING GENERAL PROVISIONS Applicability § 110.01-3 Repairs and alterations. (a) Repairs and replacements in kind must comply with...

  11. 30 CFR 57.19109 - Shaft inspection and repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shaft inspection and repair. 57.19109 Section 57.19109 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Shafts § 57.19109 Shaft inspection and repair. Shaft inspection and repair work in vertical...

  12. 30 CFR 56.19109 - Shaft inspection and repair.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shaft inspection and repair. 56.19109 Section 56.19109 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Shafts § 56.19109 Shaft inspection and repair. Shaft inspection and repair work in vertical...

  13. 30 CFR 56.13019 - Pressure system repairs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Pressure system repairs. 56.13019 Section 56... Boilers § 56.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  14. 30 CFR 57.13019 - Pressure system repairs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Pressure system repairs. 57.13019 Section 57... and Boilers § 57.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  15. 30 CFR 56.13019 - Pressure system repairs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Pressure system repairs. 56.13019 Section 56... Boilers § 56.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  16. 30 CFR 57.13019 - Pressure system repairs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Pressure system repairs. 57.13019 Section 57... and Boilers § 57.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  17. 30 CFR 57.13019 - Pressure system repairs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Pressure system repairs. 57.13019 Section 57... and Boilers § 57.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  18. 30 CFR 56.13019 - Pressure system repairs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Pressure system repairs. 56.13019 Section 56... Boilers § 56.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  19. 30 CFR 57.13019 - Pressure system repairs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Pressure system repairs. 57.13019 Section 57... and Boilers § 57.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  20. 30 CFR 56.13019 - Pressure system repairs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Pressure system repairs. 56.13019 Section 56... Boilers § 56.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  1. 30 CFR 57.13019 - Pressure system repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Pressure system repairs. 57.13019 Section 57... and Boilers § 57.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  2. 30 CFR 56.13019 - Pressure system repairs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Pressure system repairs. 56.13019 Section 56... Boilers § 56.13019 Pressure system repairs. Repairs involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be attempted until the pressure has been bled off....

  3. 27 CFR 555.216 - Repair of magazines.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Repair of magazines. 555... EXPLOSIVES, DEPARTMENT OF JUSTICE EXPLOSIVES COMMERCE IN EXPLOSIVES Storage § 555.216 Repair of magazines. Before repairing the interior of magazines, all explosive materials are to be removed and the...

  4. Cost Effective Repair Techniques for Turbine Airfoils. Volume 2

    DTIC Science & Technology

    1979-04-01

    BLADES , *GUIDE VANES , *REPAIR, TURBOFAN ENGINES , DIFFUSION BONDING, COST EFFECTIVENESS Identifiers: (U) * Turbine vanes , TF-39 engines , Activated...REPAIR TECHNIQUES FOR TURBINE AIRFOILS J. A. WEIN W. R. YOUNG GENERAL ELECTRIC COMPANY AIRCRAFT ENGINE GROUP CINCINNATI, OHIO 45215 APRIL 1979...Author: GENERAL ELECTRIC CO CINCINNATI OH AIRCRAFT ENGINE BUSINESS GROUP Unclassified Title: (U) Cost Effective Repair Techniques for

  5. History and Nomenclature of Multistrand Repairs in Digital Flexor Tendons.

    PubMed

    Savage, Robert; Tang, Jin Bo

    2016-02-01

    Multistrand core suture repairs have become the mainstay of digital flexor tendon repair in recent decades. Here we briefly describe the history of the development of these multistrand repair methods and their correct nomenclature. A historical account, their evolution, the correct use of nomenclature, and some technical points are reviewed.

  6. 14 CFR 145.107 - Satellite repair stations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Satellite repair stations. 145.107 Section 145.107 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... Data § 145.107 Satellite repair stations. (a) A certificated repair station under the...

  7. 14 CFR 145.107 - Satellite repair stations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Satellite repair stations. 145.107 Section 145.107 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... Data § 145.107 Satellite repair stations. (a) A certificated repair station under the...

  8. 14 CFR 145.107 - Satellite repair stations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Satellite repair stations. 145.107 Section 145.107 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... Data § 145.107 Satellite repair stations. (a) A certificated repair station under the...

  9. 14 CFR 145.107 - Satellite repair stations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Satellite repair stations. 145.107 Section 145.107 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED... Data § 145.107 Satellite repair stations. (a) A certificated repair station under the...

  10. 49 CFR 192.311 - Repair of plastic pipe.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Repair of plastic pipe. 192.311 Section 192.311... Lines and Mains § 192.311 Repair of plastic pipe. Each imperfection or damage that would impair the serviceability of plastic pipe must be repaired or removed. [Amdt. 192-93, 68 FR 53900, Sept. 15, 2003]...

  11. 49 CFR 192.311 - Repair of plastic pipe.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Repair of plastic pipe. 192.311 Section 192.311... Lines and Mains § 192.311 Repair of plastic pipe. Each imperfection or damage that would impair the serviceability of plastic pipe must be repaired or removed....

  12. 49 CFR 192.311 - Repair of plastic pipe.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Repair of plastic pipe. 192.311 Section 192.311... Lines and Mains § 192.311 Repair of plastic pipe. Each imperfection or damage that would impair the serviceability of plastic pipe must be repaired or removed....

  13. 49 CFR 192.311 - Repair of plastic pipe.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Repair of plastic pipe. 192.311 Section 192.311... Lines and Mains § 192.311 Repair of plastic pipe. Each imperfection or damage that would impair the serviceability of plastic pipe must be repaired or removed....

  14. 49 CFR 192.311 - Repair of plastic pipe.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Repair of plastic pipe. 192.311 Section 192.311... Lines and Mains § 192.311 Repair of plastic pipe. Each imperfection or damage that would impair the serviceability of plastic pipe must be repaired or removed....

  15. 40 CFR 51.369 - Improving repair effectiveness.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and the State shall take steps to ensure the capability exists in the repair industry to repair... industry with information and assistance related to vehicle inspection diagnosis and repair. (1) The agency... vehicles for retest. Performance monitoring shall include statistics on the number of vehicles...

  16. 48 CFR 1352.271-87 - Changes-ship repair.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Changes-ship repair. 1352.271-87 Section 1352.271-87 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CLAUSES AND...—ship repair. As prescribed in 48 CFR 1371.118, insert the following clause: Changes—Ship Repair...

  17. 33 CFR 158.240 - Ship repair yards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Ship repair yards. 158.240... Facilities: Oily Mixtures § 158.240 Ship repair yards. The reception facility that services oceangoing ships using a ship repair yard must have a capacity for receiving— (a) An amount of ballast from bunker...

  18. 48 CFR 1352.271-87 - Changes-ship repair.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Changes-ship repair. 1352.271-87 Section 1352.271-87 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CLAUSES AND...—ship repair. As prescribed in 48 CFR 1371.118, insert the following clause: Changes—Ship Repair...

  19. 29 CFR 1926.30 - Shipbuilding and ship repairing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 8 2011-07-01 2011-07-01 false Shipbuilding and ship repairing. 1926.30 Section 1926.30... Provisions § 1926.30 Shipbuilding and ship repairing. (a) General. Shipbuilding, ship repairing, alterations, and maintenance performed on ships under Government contract, except naval ship construction, is...

  20. 48 CFR 1352.271-87 - Changes-ship repair.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Changes-ship repair. 1352.271-87 Section 1352.271-87 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CLAUSES AND...—ship repair. As prescribed in 48 CFR 1371.118, insert the following clause: Changes—Ship Repair...