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1

Cellular responses to environmental DNA damage  

SciTech Connect (OSTI)

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

Not Available

1994-08-01T23:59:59.000Z

2

Cellular responses against DNA damaged by platinum anticancer drugs  

E-Print Network [OSTI]

The anticancer activity of platinum-based drugs such as cisplatin, carboplatin, and oxaliplatin is mediated by their ability to attack DNA such that generated adducts trigger numerous cellular responses. A better understanding ...

Jung, Yongwon, 1977-

2005-01-01T23:59:59.000Z

3

Integration of the phosphorylation-dependent signaling in the DNA damage response network : implications for cancer  

E-Print Network [OSTI]

The cellular response to DNA damage is an evolutionarily conserved process mediated by Ser/Thr kinases that results in the formation of multiple protein-protein complexes designed to control the cell cycle. The assembly ...

Manke, Isaac Andrew

2005-01-01T23:59:59.000Z

4

Conserved and Unconventional Responses to DNA Damage in Tetrahymena  

E-Print Network [OSTI]

in the transition G1/S phase to promote the loading of DNA polymerases. Additionally CDK prevent any further activation of pre-RC. CDK also induce phosphorylation of Sld2, Sld3 and Mcm5 that promotes the initiation of DNA synthesis. Diagram modified from Sclafani... and Holzen (2007). Cdc45 Sld2-3 S-CDK Initiation G1 phase G1/S transition S phase 21 21 mechanism to restrict pre-RC formation to only once per cell cycle (Lutzmann et al., 2006). Cdc6 in budding yeast stimulates the Abf1 binding activity...

Sandoval Oporto, Pamela

2012-07-16T23:59:59.000Z

5

A study of inter-individual differences in the DNA damage response  

E-Print Network [OSTI]

Agents that damage our DNA are omnipresent in our environment and inside our cells themselves. Left unrepaired, DNA damage can lead to premature aging, neurodegeneration and cancer. Humans have thus evolved intricate and ...

Sefta, Meriem

2012-01-01T23:59:59.000Z

6

DNA damage response to different surface chemistry of silver nanoparticles in mammalian cells  

SciTech Connect (OSTI)

Silver nanoparticles (Ag NPs) have recently received much attention for their possible applications in biotechnology and life sciences. Ag NPs are of interest to defense and engineering programs for new material applications as well as for commercial purposes as an antimicrobial. However, little is known about the genotoxicity of Ag NPs following exposure to mammalian cells. This study was undertaken to examine the DNA damage response to polysaccharide surface functionalized (coated) and non-functionalized (uncoated) Ag NPs in two types of mammalian cells; mouse embryonic stem (mES) cells and mouse embryonic fibroblasts (MEF). Both types of Ag NPs up-regulated the cell cycle checkpoint protein p53 and DNA damage repair proteins Rad51 and phosphorylated-H2AX expression. Furthermore both of them induced cell death as measured by the annexin V protein expression and MTT assay. Our observations also suggested that the different surface chemistry of Ag NPs induce different DNA damage response: coated Ag NPs exhibited more severe damage than uncoated Ag NPs. The results suggest that polysaccharide coated particles are more individually distributed while agglomeration of the uncoated particles limits the surface area availability and access to membrane bound organelles.

Ahamed, Maqusood; Karns, Michael; Goodson, Michael; Rowe, John [Department of Biology, Centre for Tissue Regeneration and Engineering, University of Dayton, Dayton-45469, OH (United States); Hussain, Saber M.; Schlager, John J. [Applied Biotechnology Branch, Human Effectiveness Directorate Air Force Research Laboratory/HEPB, Wright-Patterson Air Force Base-45433, OH (United States); Hong Yiling [Department of Biology, Centre for Tissue Regeneration and Engineering, University of Dayton, Dayton-45469, OH (United States)], E-mail: Yiling.Hong@notes.udayton.edu

2008-12-15T23:59:59.000Z

7

The role of mismatch repair and recombination in cellular responses to the DNA damaging anticancer drug Cisplatin  

E-Print Network [OSTI]

Cisplatin (cis-diamminedichloroplatinum(ll)) is a successful DNA-damaging anticancer drug used in the treatment of testicular, ovarian and other tumors. In the past decade, several mutually non-exclusive hypotheses have ...

Zdraveski, Zoran Z. (Zoran Zare), 1969-

2002-01-01T23:59:59.000Z

8

Chk2 regulates transcription-independent p53-mediated apoptosis in response to DNA damage  

SciTech Connect (OSTI)

The tumor suppressor protein p53 plays a central role in the induction of apoptosis in response to genotoxic stress. The protein kinase Chk2 is an important regulator of p53 function in mammalian cells exposed to ionizing radiation (IR). Cells derived from Chk2-deficient mice are resistant to the induction of apoptosis by IR, and this resistance has been thought to be a result of the defective transcriptional activation of p53 target genes. It was recently shown, however, that p53 itself and histone H1.2 translocate to mitochondria and thereby induces apoptosis in a transcription-independent manner in response to IR. We have now examined whether Chk2 also regulates the transcription-independent induction of apoptosis by p53 and histone H1.2. The reduced ability of IR to induce p53 stabilization in Chk2-deficient thymocytes was associated with a marked impairment of p53 and histone H1 translocation to mitochondria. These results suggest that Chk2 regulates the transcription-independent mechanism of p53-mediated apoptosis by inducing stabilization of p53 in response to IR.

Chen Chen [Department of Geriatric Research, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8522 (Japan); Shimizu, Shigeomi [Department of Post-Genomics Diseases, Osaka University Medical School, Suita, Osaka 565-0871 (Japan); Tsujimoto, Yoshihide [Department of Post-Genomics Diseases, Osaka University Medical School, Suita, Osaka 565-0871 (Japan); Motoyama, Noboru [Department of Geriatric Research, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, Obu, Aichi 474-8522 (Japan)]. E-mail: motoyama@nils.go.jp

2005-07-29T23:59:59.000Z

9

A DNA Damage-Induced, SOS-Independent Checkpoint Regulates Cell Division in Caulobacter crescentus  

E-Print Network [OSTI]

Cells must coordinate DNA replication with cell division, especially during episodes of DNA damage. The paradigm for cell division control following DNA damage in bacteria involves the SOS response where cleavage of the ...

Modell, Joshua W.

10

Systems Biology Model of Interactions Between Tissue Growth Factors and DNA Damage Pathways: Low Dose Response and Cross-Talk in TGFbeta and ATM Signaling  

SciTech Connect (OSTI)

The etiology of radiation carcinogenesis has been described in terms of aberrant changes that span several levels of biological organization. Growth factors regulate many important cellular and tissue functions including apoptosis, differentiation and proliferation. A variety of genetic and epigenetic changes of growth factors have been shown to contribute to cancer initiation and progression. It is known that cellular and tissue damage to ionizing radiation is in part initiated by the production of reactive oxygen species, which can activate cytokine signaling, and the DNA damage response pathways, most notably the ATM signaling pathway. Recently the transforming growth factor ? (TGF?) pathway has been shown to regulate or directly interact with the ATM pathway in the response to radiation. The relevance of this interaction with the ATM pathway is not known although p53 becomes phosphorylated and DNA damage responses are involved. However, growth factor interactions with DNA damage responses have not been elucidated particularly at low doses and further characterization of their relationship to cancer processes is warranted. Our goal will be to use a systems biology approach to mathematically and experimentally describe the low dose responses and cross-talk between the ATM and TGF? pathways initiated by low and high LET radiation. We will characterize ATM and TGF? signaling in epithelial and fibroblast cells using 2D models and ultimately extending to 3D organotypic cell culture models to begin to elucidate possible differences that may occur for different cell types and/or inter-cellular communication. We will investigate the roles of the Smad and Activating transcription factor 2 (ATF2) proteins as the potential major contributors to cross- talk between the TGF? and ATM pathways, and links to cell cycle control and/or the DNA damage response, and potential differences in their responses at low and high doses. We have developed various experimental approaches to apply to these problems using confocal microscopy and flow cytometry to detail changes at low dose/dose-rate in order to understand individual cell responses, and will establish our mathematical models based on the experimental findings resulting from changes in DNA repair, apoptosis and proliferation.

O'Neill, Peter [University of Oxford; Anderson, Jennifer [University of Oxford

2014-10-02T23:59:59.000Z

11

Micropatterned cell arrays for detecting DNA damage  

E-Print Network [OSTI]

Numerous agents are capable of interacting with DNA and damaging it. Permanent changes in the DNA structure can be both mutagenic and cytotoxic; therefore, methods to measure the susceptibility of cells to mutations are ...

Mittal, Sukant

2008-01-01T23:59:59.000Z

12

A DNA damage checkpoint in Caulobacter crescentus inhibits cell division through a direct interaction with FtsW  

E-Print Network [OSTI]

Following DNA damage, cells typically delay cell cycle progression and inhibit cell division until their chromosomes have been repaired. The bacterial checkpoint systems responsible for these DNA damage responses are ...

Modell, Joshua Wexler

13

The biological and metabolic fates of endogenous DNA damage products  

E-Print Network [OSTI]

DNA and other biomolecules are subjected to damaging chemical reactions during normal physiological processes and in states of pathophysiology caused by endogenous and exogenous mechanisms. In DNA, this damage affects ...

Chan, Wan Simon

14

Single cell trapping and DNA damage analysis using microwell arrays  

E-Print Network [OSTI]

With a direct link to cancer, aging, and heritable diseases as well as a critical role in cancer treatment, the importance of DNA damage is well-established. The intense interest in DNA damage in applications ranging from ...

Wood, David

15

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

E-Print Network [OSTI]

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

Woodruff, Rachel Van Etten

2008-01-01T23:59:59.000Z

16

The dynamic interplay between DNA damage and metabolism : the metabolic fate and transport of DNA lesions and novel DNA damage derived from intermediary metabolism  

E-Print Network [OSTI]

The work presented in this thesis explores two novel and complementary facets of endogenous DNA damage: the development of biomarkers of inflammation based on metabolites of DNA damage products and the formation of DNA ...

Jumpathong, Watthanachai

2014-01-01T23:59:59.000Z

17

Spatially localized generation of nucleotide sequence-specific DNA damage  

E-Print Network [OSTI]

Spatially localized generation of nucleotide sequence-specific DNA damage Dennis H. Oh* , Brett A- neously manipulated at the nucleotide level and in three dimen- sions. This approach for targeting

Boxer, Steven G.

18

Linking Cell Cycle Reentry and DNA Damage in Neurodegeneration  

E-Print Network [OSTI]

Aberrant cell cycle activity and DNA damage have been observed in neurons in association with various neurodegenerative conditions. While there is strong evidence for a causative role for these events in neurotoxicity, it ...

Kim, Dohoon

19

Nanofoams Response to Radiation Damage  

SciTech Connect (OSTI)

Conclusions of this presentation are: (1) np-Au foams were successfully synthesized by de-alloying process; (2) np-Au foams remain porous structure after Ne ion irradiation to 1 dpa; (3) SFTs were observed in irradiated np-Au foams with highest and intermediate flux, while no SFTs were observed with lowest flux; (4) SFTs were observed in irradiated np-Au foams at RT, whereas no SFTs were observed at LNT irradiation; (5) The diffusivity of vacancies in Au at RT is high enough so that the vacancies have enough time to agglomerate and thus collapse. As a result, SFTs were formed; (6) The high flux created much more damage/time, vacancies don't have enough time to diffuse or recombine. As a result, SFTs were formed.

Fu, Engang [Los Alamos National Laboratory; Serrano De Caro, Magdalena [Los Alamos National Laboratory; Wang, Yongqiang [Los Alamos National Laboratory; Nastasi, Michael [Nebraska Center for Energy Sciences Research, University of Nebraska-Lincoln, NE 68508; Zepeda-Ruiz, Luis [PLS, Lawrence Livermore National Laboratory, Livermore, CA 94551; Bringa, Eduardo M. [CONICET and Inst. Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza, 5500 Argentina; Baldwin, Jon K. [Los Alamos National Laboratory; Caro, Jose A. [Los Alamos National Laboratory

2012-07-30T23:59:59.000Z

20

Identification and characterization of tac5, a telomerase activation mutant, characterization of DNA damage responses and assessment of interactions between telomere-related proteins in Arabidopsis thaliana  

E-Print Network [OSTI]

in the genetically tractable Arabidopsis model may provide insight into the cellular response to dysfunctional telomeres. As explained in chapter IV, the yeast two-hybrid screen was utilized to confirm the interactions of ATR with AtPOT2 and Ku80 and to identify...

Jasti, Madhuri

2009-05-15T23:59:59.000Z

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


21

Inhibition of HAS2 induction enhances the radiosensitivity of cancer cells via persistent DNA damage  

SciTech Connect (OSTI)

Highlights: •HAS2 may be a promising target for the radiosensitization of human cancer. •HAS2 is elevated (up to ?10-fold) in irradiated radioresistant and -sensitive cancer cells. •HAS2 knockdown sensitizes cancer cells to radiation. •HAS2 knockdown potentiates irradiation-induced DNA damage and apoptotic death. •Thus, the irradiation-induced up-regulation of HAS2 contributes to the radioresistance of cancer cells. -- Abstract: Hyaluronan synthase 2 (HAS2), a synthetic enzyme for hyaluronan, regulates various aspects of cancer progression, including migration, invasion and angiogenesis. However, the possible association of HAS2 with the response of cancer cells to anticancer radiotherapy, has not yet been elucidated. Here, we show that HAS2 knockdown potentiates irradiation-induced DNA damage and apoptosis in cancer cells. Upon exposure to radiation, all of the tested human cancer cell lines exhibited marked (up to 10-fold) up-regulation of HAS2 within 24 h. Inhibition of HAS2 induction significantly reduced the survival of irradiated radioresistant and -sensitive cells. Interestingly, HAS2 depletion rendered the cells to sustain irradiation-induced DNA damage, thereby leading to an increase of apoptotic death. These findings indicate that HAS2 knockdown sensitizes cancer cells to radiation via persistent DNA damage, further suggesting that the irradiation-induced up-regulation of HAS2 contributes to the radioresistance of cancer cells. Thus, HAS2 could potentially be targeted for therapeutic interventions aimed at radiosensitizing cancer cells.

Shen, Yan Nan; Shin, Hyun-Jin; Joo, Hyun-Yoo; Park, Eun-Ran; Kim, Su-Hyeon; Hwang, Sang-Gu [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)] [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Park, Sang Jun; Kim, Chun-Ho [Laboratory of Tissue Engineering, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)] [Laboratory of Tissue Engineering, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Lee, Kee-Ho, E-mail: khlee@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)] [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of)

2014-01-17T23:59:59.000Z

22

A novel role for the transcriptional modulator NusA in DNA repair/damage tolerance pathways in Escherichia coli  

E-Print Network [OSTI]

All organisms must contend with the consequences of DNA damage, induced by a variety of both endogenous and exogenous sources. Mechanisms of DNA repair and DNA damage tolerance are crucial for cellular survival after DNA ...

Cohen, Susan E., Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

23

The bromodomain protein Brd4 insulates chromatin from DNA damage signalling  

E-Print Network [OSTI]

DNA damage activates a signalling network that blocks cell-cycle progression, recruits DNA repair factors and/or triggers senescence or programmed cell death. Alterations in chromatin structure are implicated in the ...

Floyd, Scott R.

24

Regulatory pathways controlling cell division after DNA damage in Caulobacter crescentus  

E-Print Network [OSTI]

All cells must coordinate DNA replication with cell division in order to faithfully propagate whole chromosomes to daughter cells. During episodes of DNA damage, cells often delay division until the lesions have been ...

Modell, Joshua Wexler

2013-01-01T23:59:59.000Z

25

GENETIC AND MOLECULAR ANALYSIS OF DNA DAMAGE REPAIR AND TOLERANCE PATHWAYS.  

SciTech Connect (OSTI)

Radiation can damage cellular components, including DNA. Organisms have developed a panoply of means of dealing with DNA damage. Some repair paths have rather narrow substrate specificity (e.g. photolyases), which act on specific pyrimidine photoproducts in a specific type (e.g., DNA) and conformation (double-stranded B conformation) of nucleic acid. Others, for example, nucleotide excision repair, deal with larger classes of damages, in this case bulky adducts in DNA. A detailed discussion of DNA repair mechanisms is beyond the scope of this article, but one can be found in the excellent book of Friedberg et al. [1] for further detail. However, some DNA damages and paths for repair of those damages important for photobiology will be outlined below as a basis for the specific examples of genetic and molecular analysis that will be presented below.

SUTHERLAND, B.M.

2001-07-26T23:59:59.000Z

26

Structural damage detection using frequency response functions  

E-Print Network [OSTI]

.........................90 5.1.2 Case 3: 1 st - 3 rd Story Braces Are Damaged .................................................92 5.1.2.1 All Four Modes Are Used for Damage Detection..........................95 5.1.2.2 The Last Two Modes... for Trial #2 with Hillclimbing #739 .......................................................................................................... 92 Figure 5.8 FRF for the 1 st Floor – 1 st - 3 rd Story Braces Are Broken SIMO – 12 DOF Symmetric...

Dincal, Selcuk

2006-04-12T23:59:59.000Z

27

Detection and quantitation of single nucleotide polymorphisms, DNA sequence variations, DNA mutations, DNA damage and DNA mismatches  

SciTech Connect (OSTI)

DNA mutation binding proteins alone and as chimeric proteins with nucleases are used with solid supports to detect DNA sequence variations, DNA mutations and single nucleotide polymorphisms. The solid supports may be flow cytometry beads, DNA chips, glass slides or DNA dips sticks. DNA molecules are coupled to solid supports to form DNA-support complexes. Labeled DNA is used with unlabeled DNA mutation binding proteins such at TthMutS to detect DNA sequence variations, DNA mutations and single nucleotide length polymorphisms by binding which gives an increase in signal. Unlabeled DNA is utilized with labeled chimeras to detect DNA sequence variations, DNA mutations and single nucleotide length polymorphisms by nuclease activity of the chimera which gives a decrease in signal.

McCutchen-Maloney, Sandra L. (Pleasanton, CA)

2002-01-01T23:59:59.000Z

28

Potential effects of environmental contaminants on P450 aromatase activity and DNA damage in swallows  

E-Print Network [OSTI]

Potential effects of environmental contaminants on P450 aromatase activity and DNA damage, to evaluate the potential effects of environmental contaminants on P450 aromatase activity in brain and gonads and DNA damage in blood cells. The tritiated water-release aromatase assay was used to measure aromatase

Mora, Miguel A.

29

Insulin signaling, dietary restriction and DNA damage : multiple roles for smk-1 in the mediation of C. elegans life span  

E-Print Network [OSTI]

role of oxidative damage and environmental stresses. Natureand environmental insults drive the accumulation of DNA damageenvironmental state. While age- related decay still occurs (due to oxidative damage and

Wolff, Suzanne Christine

2008-01-01T23:59:59.000Z

30

Chemical biology of mutagenesis and DNA repair: cellular responses to DNA alkylation  

E-Print Network [OSTI]

The reaction of DNA-damaging agents with the genome results in a plethora of lesions, commonly referred to as adducts. Adducts may cause DNA to mutate, they may represent the chemical precursors of lethal events and they ...

Shrivastav, Nidhi

31

CometChip: A High-throughput 96-Well Platform for Measuring DNA Damage in Microarrayed Human Cells  

E-Print Network [OSTI]

DNA damaging agents can promote aging, disease and cancer and they are ubiquitous in the environment and produced within human cells as normal cellular metabolites. Ironically, at high doses DNA damaging agents are also ...

Ge, Jing

32

CONSULTATION RESPONSE The Forensic Use of DNA and the National DNA Database  

E-Print Network [OSTI]

CONSULTATION RESPONSE The Forensic Use of DNA and the National DNA Database Wellcome Trust response on the important topic of the forensic use of DNA and the National DNA Database (NDNAD). Given the Trust Assembly; "Forensic DNA Databasing: A European perspective" - a biomedical ethics grant to Professor Robin

Rambaut, Andrew

33

Paraoxonase-1 genetic polymorphisms and susceptibility to DNA damage in workers occupationally exposed to organophosphate pesticides  

SciTech Connect (OSTI)

Human paraoxonase 1 (PON1) is a lipoprotein-associated enzyme involved in the detoxification of organophosphate pesticides (OPs) by hydrolyzing the bioactive oxons. Polymorphisms of the PON1 gene are responsible for variation in the expression and catalytic activity of PON1 enzyme. In the present study, we have determined (a) the prevalence of two common PON1 polymorphisms, (b) the activity of PON1 and acetylcholinesterase enzymes, and (c) the influence of PON1 genotypes and phenotypes variation on DNA damage in workers exposed to OPs. We examined 230 subjects including 115 workers exposed to OPs and an equal number of normal healthy controls. The results revealed that PON1 activity toward paraoxon (179.19 {+-} 39.36 vs. 241.52 {+-} 42.32 nmol/min/ml in controls) and phenylacetate (112.74 {+-} 17.37 vs. 134.28 {+-} 25.49 {mu}mol/min/ml in controls) was significantly lower in workers than in control subjects (p < 0.001). No significant difference was observed in the distribution of genotypes and allelic frequencies of PON1{sub 192}QR (Gln/Arg) and PON1{sub 55}LM (Leu/Met) in workers and control subjects (p > 0.05). The PON1 activity toward paraoxonase was found to be significantly higher in the R/R (Arg/Arg) genotypes than Q/R (Gln/Arg) and lowest in Q/Q (Gln/Gln) genotypes in both workers and control subjects (p < 0.001). For PON1{sub 55}LM (Leu/Met), PON1 activity toward paraoxonase was observed to be higher in individuals with L/L (Leu/Leu) genotypes and lowest in individuals with M/M (Met/Met) genotypes in both groups (p < 0.001). No influence of PON1 genotypes and phenotypes was seen on the activity of acetylcholinesterase and arylesterase. The DNA damage was observed to be significantly higher in workers than in control subjects (p < 0.05). Further, the individuals who showed least paraoxonase activity i.e., those with (Q/Q [Gln/Gln] and M/M [Met/Met]) genotypes showed significantly higher DNA damage compared to other isoforms in workers exposed to OPs (p < 0.05). The results indicate that the individuals with PON1 Q/Q and M/M genotypes are more susceptible toward genotoxicity. In conclusion, the study suggests wide variation in enzyme activities and DNA damage due to polymorphisms in PON1 gene, which might have an important role in the identification of individual risk factors in workers occupationally exposed to OPs.

Singh, Satyender [Division of Biochemistry and Biotechnology, National Centre for Disease Control, 22, Sham Nath Marg, Delhi-110054 (India); Kumar, Vivek [Environmental Biochemistry and Molecular Biology laboratory, Department of Biochemistry, University College of Medical Sciences and GTB Hospital, University of Delhi, Dilshad Garden, Delhi-110095 (India); Thakur, Sachin [Division of Biochemistry and Biotechnology, National Centre for Disease Control, 22, Sham Nath Marg, Delhi-110054 (India); Presently at, Department of Biochemistry, University of Texas Health Science Center at San Antonio (UTHSCSA), 7703 Floyd Curl Drive, San Antonio, TX 78229-3900 (United States); Banerjee, Basu Dev [Environmental Biochemistry and Molecular Biology laboratory, Department of Biochemistry, University College of Medical Sciences and GTB Hospital, University of Delhi, Dilshad Garden, Delhi-110095 (India); Rautela, Rajender Singh; Grover, Shyam Sunder; Rawat, Devendra Singh [Division of Biochemistry and Biotechnology, National Centre for Disease Control, 22, Sham Nath Marg, Delhi-110054 (India); Pasha, Syed Tazeen [National Programme for Prevention and Control of Fluorosis, DGHS, Ministry of Health and Family Welfare, Government of India, Nirman Bhavan, New Delhi 110011 (India); Jain, Sudhir Kumar [Centre for Epidemiology and Parasitic Diseases, National Centre for Disease Control, 22, Sham Nath Marg, Delhi-110054 (India); Ichhpujani, Rattan Lal [Division of Biochemistry and Biotechnology, National Centre for Disease Control, 22, Sham Nath Marg, Delhi-110054 (India); National Programme for Prevention and Control of Fluorosis, DGHS, Ministry of Health and Family Welfare, Government of India, Nirman Bhavan, New Delhi 110011 (India); Rai, Arvind, E-mail: arvindrai.nicd@gmail.com [Division of Biochemistry and Biotechnology, National Centre for Disease Control, 22, Sham Nath Marg, Delhi-110054 (India)

2011-04-15T23:59:59.000Z

34

To be submitted to Continuum Mechanics and Thermodynamics From the onset of damage to rupture: construction of responses with damage  

E-Print Network [OSTI]

To be submitted to Continuum Mechanics and Thermodynamics From the onset of damage to rupture: construction of responses with damage localization for a general class of gradient damage models Kim Pham solutions for the traction problem of an elastic damaging bar. This bar has a softening behavior which obeys

Boyer, Edmond

35

The role of ClpXP-mediated proteolysis in resculpting the proteome after DNA damage  

E-Print Network [OSTI]

When faced with environmental assaults, E. coli can take extreme measures to survive. For example, starving bacteria consume their own proteins, and bacteria with severe DNA damage introduce mutations into their genomes. ...

Neher, Saskia B. (Saskia Byerly)

2005-01-01T23:59:59.000Z

36

Mechanistic investigation of an anticancer agent that damages DNA and interacts with the androgen receptor  

E-Print Network [OSTI]

The 11[beta] molecule comprises a ligand for the androgen receptor (AR), which is crucial to progression and survival of many prostate cancers, tethered to a DNA-damaging aniline mustard. The compound was designed to exhibit ...

Proffitt, Kyle David

2009-01-01T23:59:59.000Z

37

Mechanistic investigation of anticancer agents that damage DNA and interact with the estrogen receptor  

E-Print Network [OSTI]

One of the primary goals of cancer chemotherapy is the design of antitumor agents that achieve selective targeting of tumor cells while minimizing toxicity to normal tissues. We have synthesized a series of DNA damaging ...

Gopal, Sreeja

2009-01-01T23:59:59.000Z

38

assessing dna damage: Topics by E-print Network  

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

damage may not only reduce the number of amplifiable template molecules, but may also lead to the generation of erroneous sequence information. A qualitative and quantitative...

39

affects dna damage: Topics by E-print Network  

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

damage may not only reduce the number of amplifiable template molecules, but may also lead to the generation of erroneous sequence information. A qualitative and quantitative...

40

Cytogenetic status and oxidative DNA-damage induced by atorvastatin in human peripheral blood lymphocytes: Standard and Fpg-modified comet assay  

SciTech Connect (OSTI)

To investigate the genotoxic potential of atorvastatin on human lymphocytes in vitro standard comet assay was used in the evaluation of basal DNA damage and to investigate possible oxidative DNA damage produced by reactive oxygen species (ROS) Fpg-modified version of comet assay was also conducted. In addition to these techniques the new criteria for scoring micronucleus test were applied for more complete detection of baseline damage in binuclear lymphocytes exposed to atorvastatin 80 mg/day in different time periods by virtue of measuring the frequency of micronuclei, nucleoplasmic bridges and nuclear buds. All parameters obtained with the standard comet assay and Fpg-modified comet assay were significantly higher in the treated than in control lymphocytes. The Fpg-modified comet assay showed a significantly greater tail length, tail intensity, and tail moment in all treated lymphocytes than did the standard comet assay, which suggests that oxidative stress is likely to be responsible for DNA damage. DNA damage detected by the standard comet assay indicates that some other mechanism is also involved. In addition to the comet assay, a total number of micronuclei, nucleoplasmic bridges and nuclear buds were significantly higher in the exposed than in controlled lymphocytes. Regression analyses showed a positive correlation between the results obtained by the comet (Fpg-modified and standard) and micronucleus assay. Overall, the study demonstrated that atorvastatin in its highest dose is capable of producing damage on the level of DNA molecule and cell.

Gajski, Goran [Institute for Medical Research and Occupational Health, Mutagenesis Unit, 10000 Zagreb (Croatia)], E-mail: ggajski@imi.hr; Garaj-Vrhovac, Vera [Institute for Medical Research and Occupational Health, Mutagenesis Unit, 10000 Zagreb (Croatia); Orescanin, Visnja [Ruder Boskovic Institute, 10000 Zagreb (Croatia)

2008-08-15T23:59:59.000Z

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


41

Understanding cell fate decisions in response to 0?-Methylguanine DNA lesions  

E-Print Network [OSTI]

The stability of the genome is constantly challenged by both endogenous and exogenous DNA damaging agents. DNA damage, if left unrepaired, can give rise to permanent genetic alterations that ultimately increase our risk ...

Noonan, Ericka Marie

2011-01-01T23:59:59.000Z

42

DNA Damage Causes p27^(Kip1) Accumulation Through COP1 Signaling  

E-Print Network [OSTI]

consequences of this phenomenon are poorly understood. Here, we report that p27 levels were elevated after DNA damage, with concurrent reduction of COP1 levels. Mechanistic studies showed that COP1 directly interacted with p27 through a VP motif on p27...

Choi, Hyun Ho

2014-05-06T23:59:59.000Z

43

Repair of gamma-ray-induced DNA base damage in xeroderma pigmentosum cells  

SciTech Connect (OSTI)

The repair of DNA damage produced by /sup 137/Cs gamma irradiation was measured with a preparation from Micrococcus luteus containing DNA damage-specific endonucleases in combination with alkaline elution. The frequency of these endonuclease sensitive sites (ESS) was determined after 54 or 110 Gy of oxic irradiation in normal and xeroderma pigmentosum (XP) fibroblasts from complementation groups A, C, D, and G. Repair was rapid in all cell strains with greater than 50% repair after 1.5 h of repair incubation. At later repair times, 12-17 h, more ESS remained in XP than in normal cells. The frequency of excess ESS in XP cells was approximately 0.04 per 10(9) Da of DNA per Gy which was equivalent to 10% of the initial ESS produced. The removal of ESS was comparable in XP cells with normal radiosensitivity and XP3BR cells which have been reported to be moderately radiosensitive.

Fornace, A.J. Jr.; Dobson, P.P.; Kinsella, T.J.

1986-04-01T23:59:59.000Z

44

RecA acts in trans to allow replication of damaged DNA by DNA polymerase V  

E-Print Network [OSTI]

, Michael M. Cox2 , Roger Woodgate3 & Myron F. Goodman1 The DNA polymerase V (pol V) and RecA proteins

Cox, Michael M.

45

Genome-Wide Identification and 3D Modeling of Proteins involved in DNA Damage Recognition and Repair (Final Report)  

SciTech Connect (OSTI)

OAK-B135 DNA Damage Recognition and Repair (DDR and R) proteins play a critical role in cellular responses to low-dose radiation and are associated with cancer. the authors have performed a systematic, genome-wide computational analysis of genomic data for human genes involved in the DDR and R process. The significant achievements of this project include: (1) Construction of the computational pipeline for searching DDR and R genes, building and validation of 3D models of proteins involved in DDR and R; (2) Functional and structural annotation of the 3D models and generation of comprehensive lists of suggested knock-out mutations; (3) Important improvement of macromolecular docking technology and its application to predict the DNA-Protein complex conformation; (4) Development of a new algorithm for improved analysis of high-density oligonucleotide arrays for gene expression profiling; (5) Construction and maintenance of the DNA Damage Recognition and Repair Database; and (6) Producing 14 research papers (10 published and 4 in preparation).

Ruben A. Abagyan, PhD

2004-04-15T23:59:59.000Z

46

A molecular dynamics simulation of DNA damage induction by ionizing radiation  

E-Print Network [OSTI]

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

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

2013-01-01T23:59:59.000Z

47

Structure and mechanism of the UvrA?UvrB DNA damage sensor  

SciTech Connect (OSTI)

Nucleotide excision repair (NER) is used by all organisms to eliminate DNA lesions. We determined the structure of the Geobacillus stearothermophilus UvrA-UvrB complex, the damage-sensor in bacterial NER and a new structure of UvrA. We observe that the DNA binding surface of UvrA, previously found in an open shape that binds damaged DNA, also exists in a closed groove shape compatible with native DNA only. The sensor contains two UvrB molecules that flank the UvrA dimer along the predicted path for DNA, {approx}80 {angstrom} from the lesion. We show that the conserved signature domain II of UvrA mediates a nexus of contacts among UvrA, UvrB and DNA. Further, in our new structure of UvrA, this domain adopts an altered conformation while an adjacent nucleotide binding site is vacant. Our findings raise unanticipated questions about NER and also suggest a revised picture of its early stages.

Pakotiprapha, Danaya; Samuels, Martin; Shen, Koning; Hu, Johnny H.; Jeruzalmi, David (Harvard)

2012-04-17T23:59:59.000Z

48

Protection of cisplatin-induced spermatotoxicity, DNA damage and chromatin abnormality by selenium nano-particles  

SciTech Connect (OSTI)

Cisplatin (CIS), an anticancer alkylating agent, induces DNA adducts and effectively cross links the DNA strands and so affects spermatozoa as a male reproductive toxicant. The present study investigated the cellular/biochemical mechanisms underlying possible protective effect of selenium nano-particles (Nano-Se) as an established strong antioxidant with more bioavailability and less toxicity, on reproductive toxicity of CIS by assessment of sperm characteristics, sperm DNA integrity, chromatin quality and spermatogenic disorders. To determine the role of oxidative stress (OS) in the pathogenesis of CIS gonadotoxicity, the level of lipid peroxidation (LPO), antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) and peroxynitrite (ONOO) as a marker of nitrosative stress (NS) and testosterone (T) concentration as a biomarker of testicular function were measured in the blood and testes. Thirty-two male Wistar rats were equally divided into four groups. A single IP dose of CIS (7 mg/kg) and protective dose of Nano-Se (2 mg/kg/day) were administered alone or in combination. The CIS-exposed rats showed a significant increase in testicular and serum LPO and ONOO level, along with a significant decrease in enzymatic antioxidants levels, diminished serum T concentration and abnormal histologic findings with impaired sperm quality associated with increased DNA damage and decreased chromatin quality. Coadministration of Nano-Se significantly improved the serum T, sperm quality, and spermatogenesis and reduced CIS-induced free radical toxic stress and spermatic DNA damage. In conclusion, the current study demonstrated that Nano-Se may be useful to prevent CIS-induced gonadotoxicity through its antioxidant potential. Highlights: ? Cisplatin (CIS) affects spermatozoa as a male reproductive toxicant. ? Effect of Nano-Se on CIS-induced spermatotoxicity was investigated. ? CIS-exposure induces oxidative sperm DNA damage and impairs steroidogenesis. ? Nano-Se retained sperm quality against CIS-induced free radicals toxic stress.

Rezvanfar, Mohammad Amin; Rezvanfar, Mohammad Ali [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences (TUMS), Tehran (Iran, Islamic Republic of)] [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences (TUMS), Tehran (Iran, Islamic Republic of); Shahverdi, Ahmad Reza [Department of Pharmaceutical Biotechnology and Biotechnology Research Centre, Faculty of Pharmacy, TUMS, Tehran (Iran, Islamic Republic of)] [Department of Pharmaceutical Biotechnology and Biotechnology Research Centre, Faculty of Pharmacy, TUMS, Tehran (Iran, Islamic Republic of); Ahmadi, Abbas [Department of Histology and Embryology, Faculty of Veterinary Medicine, Urmia University, Urmia (Iran, Islamic Republic of)] [Department of Histology and Embryology, Faculty of Veterinary Medicine, Urmia University, Urmia (Iran, Islamic Republic of); Baeeri, Maryam; Mohammadirad, Azadeh [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences (TUMS), Tehran (Iran, Islamic Republic of)] [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences (TUMS), Tehran (Iran, Islamic Republic of); Abdollahi, Mohammad, E-mail: mohammad.abdollahi@utoronto.ca [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences (TUMS), Tehran (Iran, Islamic Republic of)] [Department of Toxicology and Pharmacology, Faculty of Pharmacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences (TUMS), Tehran (Iran, Islamic Republic of)

2013-02-01T23:59:59.000Z

49

Quantitative Analysis of Clustered DNA Damages Induced by Silicon Beams of Different Kinetic Energy  

SciTech Connect (OSTI)

Humans may b exposed to highly energetic charged particle radiation as a result of medical treatments, occupational activitie or accidental events. In recent years, our increasing presence and burgeoning interest in space exploration beyond low Earth orbit has led to a large increase in the research of the biological effects ofcharged particle radiation typical of that encountered in the space radiation environment. The study of the effects of these types of radiation qualities in terms ofDNA damage induction and repair is fundamental to understand mechanisms both underlying their greater biological effectiveness as we)) as the short and long term risks of health effects such as carcinogenesis, degen rative diseases and premature aging. Charged particle radiation induces a variety of DNA alterations, notably bistranded clustered damages, defined as two or more closely-opposed strand break , oxidized bases or abasic sites within a few helical turns. The induction of such highly complex DNA damage enhances the probability of incorrect or incomplete repair and thus constitutes greater potential for genomic instability, cell death and transformation.

Keszenman D. J.; Keszenman, D.J.; Bennett, P.V.; Sutherland, B.M.; Wilson, P.F.

2013-05-14T23:59:59.000Z

50

Damage Threats and Response of Final Optics for Laser-Fusion Power Plants  

E-Print Network [OSTI]

Damage Threats and Response of Final Optics for Laser-Fusion Power Plants M. S. Tillack1 , S. A the various damage threats and also provides nominal goals for a power plant. These goals are driven-1597 The final optics for laser-IFE (inertial fusion energy) power plants will be exposed to a variety of damage

Tillack, Mark

51

Metabolites of arsenic and increased DNA damage of p53 gene in arsenic plant workers  

SciTech Connect (OSTI)

Recent studies have shown that monomethylarsonous acid is more cytotoxic and genotoxic than arsenate and arsenite, which may attribute to the increased levels of reactive oxygen species. In this study, we used hydride generation-atomic absorption spectrometry to determine three arsenic species in urine of workers who had been working in arsenic plants,and calculated primary and secondary methylation indexes. The damages of exon 5, 6, 8 of p53 gene were determined by the method developed by Sikorsky, et al. Results show that the concentrations of each urinary arsenic species,and damage indexes of exon 5 and 8 of p53 gene in the exposed population were significantly higher, but SMI was significantly lower than in the control group. The closely positive correlation between the damage index of exon 5 and PMI,MMA, DMA were found, but there was closely negative correlation between the damage index of exon 5 and SMI. Those findings suggested that DNA damage of exon 5 and 8 of p53 gene existed in the population occupationally exposed to arsenic. For exon 5, the important factors may include the model of arsenic metabolic transformation, the concentrations of MMA and DMA, and the MMA may be of great importance. - Research Highlights: > In our study, the mean SMI for workers came from arsenic plants is 4.06, so they may be in danger. > There are more MMA, there are more damage of exon 5 of p53 gene. > MMA and damage of exon 5 of p53 gene may be useful biomarkers to assess adverse health effects caused by arsenic.

Wen Weihua, E-mail: Dongsijiehua@sina.com [Department of Occupational Health, Yunnan Provincial Center for Disease Control and Prevention, No. 158, Dongsi Street, Kunming, Yunnan, 650022 (China); Public Health College, Huazhong University of Science and Technology, No. 13, Hangkong Road, Wuhan City, Hubei, 430030 (China); Wen Jinghua [Guizhou College of Finance and Economics, No. 276, Chongguan Road, Guiyang, Guizhou, 550004 (China); Lu Lin [Department of Occupational Health, Yunnan Provincial Center for Disease Control and Prevention, No. 158, Dongsi Street, Kunming, Yunnan, 650022 (China); Liu Hua [The First Affiliated Hospital of Kunming Medical College, No. 295 Xichang Road, Kunming, Yunnan, 650032 (China); Yang Jun; Cheng Huirong [Department of Occupational Health, Yunnan Provincial Center for Disease Control and Prevention, No. 158, Dongsi Street, Kunming, Yunnan, 650022 (China); Che Wangjun [The First Division of Public Health, Kunming Center for Disease Control and Prevention, No. 4, Ziyun Road, Xishan District, Kunming, Yunnan 650228 (China); Li Liang [Honghe Zhou Center for Disease Control and Prevention, No. 1, Guannan Road, Mengzi City, Yunnan, 661100 (China); Zhang Guanbei [Yunnan Institute for Drug Abuse, Kunming, 650028 (China)

2011-07-01T23:59:59.000Z

52

Generation of DNA-Damaging Reactive Oxygen Species via the Autoxidation of Hydrogen Sulfide under Physiologically Relevant  

E-Print Network [OSTI]

Generation of DNA-Damaging Reactive Oxygen Species via the Autoxidation of Hydrogen Sulfide under found that micromolar concentrations of H2S generated single-strand DNA cleavage. Mechanistic studies indicate that this process involved autoxidation of H2S to generate superoxide, hydrogen peroxide, and

Gates, Kent. S.

53

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

SciTech Connect (OSTI)

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

Marchetti, Francesco; Wyrobek, Andrew J.

2009-01-18T23:59:59.000Z

54

DNA Damage-inducible Genes as Biomarkers for Exposures to Environmental Agents  

E-Print Network [OSTI]

A biodosimetric approach to determine alpha-particle dose to the respiratory tract epithelium from known exposures to radon has been developed in the rat. Cytotoxicity assays have been used to obtain dose-conversion factors for cumulative exposures typical of those encountered by underground uranium miners. However, this approach is not sensitive enough to derive doseconversion factors for indoor radon exposures. The expression of DNA damage-inducible genes is being investigated as a biomarker of exposure to radon progeny. Exposure of cultures of A549 cells to alpha particles resulted in an increase in the protein levels of the DNA damage-inducible genes, p53, Cip1, and Gadd45. These protein changes were associated with a transient arrest of cells passing through the cell cycle. This arrest was typified by an increase in the number of cells in the G, and G2 phases and a decrease in the number of cells in the S phase. The effect of inhaled alpha particles (radon progeny) in rats was examined in the epithelial cells of the lateral wall of the anterior nasal cavity. Exposures to radon progeny resulted in a significant increase in the number of cells in the G, phase and a decrease in the number of cells in the S phase. These cell-cycle changes were concomitant with an increase in the number of cells containing DNA strand breaks. These results suggest a commonality between cell-cycle events in vitro and in vivo following exposure to ionizing radiation. In addition to ionizing radiation, A549 cells were exposed to 4-nitroquinoline-1-oxide, methyl methanesulphonate, crocidolite asbestos, and glass microfiber. These studies showed that physical and chemical agents induce different expression patterns of p53, Cipl, and Gaddl 53 proteins and they could be used to discriminate between toxic and nontoxic materials such as asbestos and glass microfiber. The measurement of gene expression in A549 cells may provide a means to identify a broad spectrum of physical and chemical toxicants encountered in the environment. Environ Health Perspect 1 05(Suppl 4):913-918 (1997) Key words: radiation, fibers, chemicals, DNA damage-inducible genes

Neil F. Johnson; Thomas R. Carpenter; Richard J. Jaramillo; Teresa A. Liberati

55

A Mitotic Phosphorylation Feedback Network Connects Cdk1, Plk1, 53BP1, and Chk2 to Inactivate the G2/M DNA Damage Checkpoint  

E-Print Network [OSTI]

DNA damage checkpoints arrest cell cycle progression to facilitate DNA repair. The ability to survive genotoxic insults depends not only on the initiation of cell cycle checkpoints but also on checkpoint maintenance. While ...

Yaffe, Michael B.

56

DNA damage-inducible genes as biomarkers for exposures to environmental agents  

SciTech Connect (OSTI)

A biodosimetric approach to determine alpha-particle dose to the respiratory tract epithelium from known exposures to radon has been developed in the rat. Cytotoxicity assays have been used to obtain dose-conversion factors for cumulative exposures typical of those encountered by underground uranium miners. However, this approach is not sensitive enough to derive close-conversion factors for indoor radon exposures. The expression of DNA damage-inducible genes is being investigated as a biomarker of exposure to radon progeny. Exposure of cultures of A549 cells to alpha particles resulted in an increase in the protein levels of the DNA damage-inducible genes, p53, Cip 1, and Gadd45. These protein changes were associated with a transient arrest of cells passing through the cell cycle. This arrest was typified by an increase in the number of cells in the G{sub 1} and G{sub 2} phases and a decrease in the number of cells in the S phase. The effect of inhaled alpha particles (radon progeny) in rats was examined in the epithelial cells of the lateral wall of the anterior nasal cavity. Exposures to radon progeny resulted in a significant increase in the number of cells in the G{sub 1} phase and a decrease in the number of cells in the S phase. These cell-cycle changes were concomitant with an increase in the number of cells containing DNA strand breaks. In addition to ionizing radiation, A549 cells were exposed to 4-nitroquinoline-1-oxide, methyl methanesulphonate, crocidolite asbestos, and glass microfiber. These studies showed that physical and chemical agents induce different expression patterns of p53, Cip 1, and Gadd153 proteins and they could be used to discriminate between toxic and nontoxic materials such as asbestos and glass microfiber. The measurement of gene expression in A549 cells may provide a means to identify a broad spectrum of physical and chemical toxicants encountered in the environment. 9 figs., 42 refs.

Johnson, N.F.; Carpenter, T.R.; Jaramillo, R.J.; Liberati, T.A. [Inhalation Toxicology Research Institute, Albuquerque, NM (United States)

1997-06-01T23:59:59.000Z

57

DNA damage in barn swallows (Hirundo rustica) from the Chernobyl region detected by use of the comet assay  

E-Print Network [OSTI]

DNA damage in barn swallows (Hirundo rustica) from the Chernobyl region detected by use November 2009 Accepted 19 November 2009 Available online 24 November 2009 Keywords: Barn swallow Chernobyl swallows (Hirundo rustica) inhabiting the Chernobyl region to evaluate whether chronic exposure to low

Mousseau, Timothy A.

58

c-Myc degradation induced by DNA damage results in apoptosis of CHO Man-Rong Jiang1  

E-Print Network [OSTI]

of UV41 cells by TC treatment. Further analysis showed that degradation of the c-Myc protein in TC, MG132, reduced both the degradation of c-Myc and apoptosis in TC-treated UV41 cells. Expression-Myc degradation induced by DNA damage in the presence of TC contributes to induction of apoptosis of UV41 cells

Tian, Weidong

59

Predictive storm damage modeling and optimizing crew response to improve storm response operations  

E-Print Network [OSTI]

Utility infrastructures are constantly damaged by naturally occurring weather. Such damage results in customer service interruption and repairs are necessary to return the system to normal operation. In most cases these ...

Whipple, Sean David

2014-01-01T23:59:59.000Z

60

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

SciTech Connect (OSTI)

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

O'Neil, Peter

2009-05-15T23:59:59.000Z

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


61

Examination of the damage and failure response of tantalum and copper under varied shock loading conditions  

SciTech Connect (OSTI)

A number of plate impact experiments have been conducted on high purity polycrystalline tantalum and copper samples using graded flyer plate configurations to alter the loading profile. These experiments are designed in a way so that a broad range of damage regimes are probed. The results show that the nucleation of damage primarily occurs at the grain boundaries of the materials. This affords us the opportunity to propose a porosity damage nucleation criterion which begins to account for the length scales of the microstructure (grain size distribution) and the mechanical response of the grain boundary regions (failure stress distribution). This is done in the context of a G-T-N type model for the ductile damage and failure response of both the materials examined. The role of micro-inertial effects on the porosity growth process is also considered.

Bronkhorst, Curt A [Los Alamos National Laboratory; Dennis - Koller, Darcie [Los Alamos National Laboratory; Cerreta, Ellen K [Los Alamos National Laboratory; Gray Ill, George T [Los Alamos National Laboratory; Bourne, Neil [AWE-ALDERMASTON

2010-12-16T23:59:59.000Z

62

Silencing of poly(ADP-ribose) glycohydrolase sensitizes lung cancer cells to radiation through the abrogation of DNA damage checkpoint  

SciTech Connect (OSTI)

Highlights: •Radiosensitization by PARG silencing was observed in multiple lung cancer cells. •PAR accumulation was enhanced by PARG silencing after DNA damage. •Radiation-induced G2/M arrest and checkpoint activation were impaired by PARG siRNA. -- Abstract: Poly(ADP-ribose) glycohydrolase (PARG) is a major enzyme that plays a role in the degradation of poly(ADP-ribose) (PAR). PARG deficiency reportedly sensitizes cells to the effects of radiation. In lung cancer, however, it has not been fully elucidated. Here, we investigated whether PARG siRNA contributes to an increased radiosensitivity using 8 lung cancer cell lines. Among them, the silencing of PARG induced a radiosensitizing effect in 5 cell lines. Radiation-induced G2/M arrest was largely suppressed by PARG siRNA in PC-14 and A427 cells, which exhibited significantly enhanced radiosensitivity in response to PARG knockdown. On the other hand, a similar effect was not observed in H520 cells, which did not exhibit a radiosensitizing effect. Consistent with a cell cycle analysis, radiation-induced checkpoint signals were not well activated in the PC-14 and A427 cells when treated with PARG siRNA. These results suggest that the increased sensitivity to radiation induced by PARG knockdown occurs through the abrogation of radiation-induced G2/M arrest and checkpoint activation in lung cancer cells. Our findings indicate that PARG could be a potential target for lung cancer treatments when used in combination with radiotherapy.

Nakadate, Yusuke [Shien-Lab, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan) [Shien-Lab, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Department of Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Kodera, Yasuo; Kitamura, Yuka [Shien-Lab, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan)] [Shien-Lab, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Tachibana, Taro [Department of Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan)] [Department of Bioengineering, Graduate School of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585 (Japan); Tamura, Tomohide [Division of Thoracic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan)] [Division of Thoracic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); Koizumi, Fumiaki, E-mail: fkoizumi@ncc.go.jp [Division of Thoracic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan)] [Division of Thoracic Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan)

2013-11-29T23:59:59.000Z

63

Reactive oxygen species and oxidative DNA damage mediate the cytotoxicity of tungsten-nickel-cobalt alloys in vitro  

SciTech Connect (OSTI)

Tungsten alloys (WA) have been introduced in an attempt to find safer alternatives to depleted uranium and lead munitions. However, it is known that at least one alloy, 91% tungsten-6% nickel-3% cobalt (WNC-91-6-3), causes rhabdomyosarcomas when fragments are implanted in rat muscle. This raises concerns that shrapnel, if not surgically removable, may result in similar tumours in humans. There is therefore a clear need to develop rapid and robust in vitro methods to characterise the toxicity of different WAs in order to identify those that are most likely to be harmful to human health and to guide development of new materials in the future. In the current study we have developed a rapid visual in vitro assay to detect toxicity mediated by individual WA particles in cultured L6-C11 rat muscle cells. Using a variety of techniques (histology, comet assay, caspase-3 activity, oxidation of 2'7'-dichlorofluorescin to measure the production of reactive oxygen species and whole-genome microarrays) we show that, in agreement with the in vivo rat carcinogenicity studies, WNC-91-6-3 was the most toxic of the alloys tested. On dissolution, it produces large amounts of reactive oxygen species, causes significant amounts of DNA damage, inhibits caspase-3, triggers a severe hypoxic response and kills the cells in the immediate vicinity of the alloy particles within 24 h. By combining these in vitro data we offer a mechanistic explanation of the effect of this alloy in vivo and show that in vitro tests are a viable alternative for assessing new alloys in the future.

Harris, R.M.; Williams, T.D.; Hodges, N.J.; Waring, R.H., E-mail: R.H.Waring@bham.ac.uk

2011-01-01T23:59:59.000Z

64

P450 aromatase alterations and DNA damage as avian pollution biomarkers in cliff and cave swallow breeding near the Rio Grande region, Texas  

E-Print Network [OSTI]

populations lacking proper water and sewage infrastructure. Cliff (Petrochelidon pyrrhonota) and cave (P. fulva) swallows breeding near the Rio Grande were selected to monitor aromatase activity alterations and DNA damage. Swallows were sampled at six sites...

Sitzlar, Megan Annette

2006-04-12T23:59:59.000Z

65

atr-mediated dna damage: Topics by E-print Network  

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

damage may not only reduce the number of amplifiable template molecules, but may also lead to the generation of erroneous sequence information. A qualitative and quantitative...

66

aluminium-induced dna damage: Topics by E-print Network  

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

damage may not only reduce the number of amplifiable template molecules, but may also lead to the generation of erroneous sequence information. A qualitative and quantitative...

67

atr-dependent dna damage: Topics by E-print Network  

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

damage may not only reduce the number of amplifiable template molecules, but may also lead to the generation of erroneous sequence information. A qualitative and quantitative...

68

Combined experimental and computational analysis of DNA damage signaling reveals context-dependent roles for Erk in apoptosis and G1/S arrest after genotoxic stress  

E-Print Network [OSTI]

Following DNA damage, cells display complex multi-pathway signaling dynamics that connect cell-cycle arrest and DNA repair in G1, S, or G2/M phase with phenotypic fate decisions made between survival, cell-cycle re-entry ...

Tentner, Andrea R

69

E-Print Network 3.0 - alternative dna damage Sample Search Results  

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

and Medicine 51 RADIATION RESEARCH 168, 499506 (2007) 0033-758707 15.00 Summary: degradation upon an alternative substrate gen- erated after UV-radiation-induced DNA...

70

E-Print Network 3.0 - ancient dna damage Sample Search Results  

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

have recently been applied to ancient DNA (Green et al., 2006; Poinar et al., 2006; Stiller et al... ., 2006). These methods open new possibilities for the retrieval of ancient...

71

An unprecedented nucleic acid capture mechanism for excision of DNA damage  

SciTech Connect (OSTI)

DNA glycosylases that remove alkylated and deaminated purine nucleobases are essential DNA repair enzymes that protect the genome, and at the same time confound cancer alkylation therapy, by excising cytotoxic N3-methyladenine bases formed by DNA-targeting anticancer compounds. The basis for glycosylase specificity towards N3- and N7-alkylpurines is believed to result from intrinsic instability of the modified bases and not from direct enzyme functional group chemistry. Here we present crystal structures of the recently discovered Bacillus cereus AlkD glycosylase in complex with DNAs containing alkylated, mismatched and abasic nucleotides. Unlike other glycosylases, AlkD captures the extrahelical lesion in a solvent-exposed orientation, providing an illustration for how hydrolysis of N3- and N7-alkylated bases may be facilitated by increased lifetime out of the DNA helix. The structures and supporting biochemical analysis of base flipping and catalysis reveal how the HEAT repeats of AlkD distort the DNA backbone to detect non-Watson-Crick base pairs without duplex intercalation.

Rubinson, Emily H.; Prakasha Gowda, A.S.; Spratt, Thomas E.; Gold, Barry; Eichmanbrand, Brandt F. (Pitt); (Vanderbilt); (Penn)

2010-11-18T23:59:59.000Z

72

Photochemistry and Photobiology, 2005, 81: 8995 Photoinduced DNA Cleavage and Cellular Damage in Human Dermal  

E-Print Network [OSTI]

1 Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, MD . Furthermore, upon irradiation with visible light, DAP is able to nick plasmid DNA in the presence of oxygen. The concentration of DAP that resulted in 50% cell death was 172 6 9 lM in the dark and 13 6 1 lM after irradiation

Turro, Claudia

73

Pliable DNA Conformation of Response Elements Bound to Transcription Factor p63  

SciTech Connect (OSTI)

We show that changes in the nucleotide sequence alter the DNA conformation in the crystal structures of p63 DNA-binding domain (p63DBD) bound to its response element. The conformation of a 22-bp canonical response element containing an AT spacer between the two half-sites is unaltered compared with that containing a TA spacer, exhibiting superhelical trajectory. In contrast, a GC spacers abolishes the DNA superhelical trajectory and exhibits less bent DNA, suggesting that increased GC content accompanies increased double helix rigidity. A 19-bp DNA, representing an AT-rich response element with overlapping half-sites, maintains superhelical trajectory and reveals two interacting p63DBD dimers crossing one another at 120{sup o}. p63DBD binding assays to response elements of increasing length complement the structural studies. We propose that DNA deformation may affect promoter activity, that the ability of p63DBD to bind to superhelical DNA suggests that it is capable of binding to nucleosomes, and that overlapping response elements may provide a mechanism to distinguish between p63 and p53 promoters.

Chen, Chen; Gorlatova, Natalia; Herzberg, Osnat (Maryland)

2012-05-02T23:59:59.000Z

74

E-Print Network 3.0 - activates dna damage Sample Search Results  

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

23, 1998, Copyright 1998 by Cell Press Reconstitution of an SOS Response Pathway Summary: BCD enzyme facilitates the formation of an activeSummary RecA nucleoprotein filament on...

75

Rat colonic reactive oxygen species production and DNA damage are mediated by diet and age  

E-Print Network [OSTI]

is based on the theory of decreased ROS in response to respiratory chain suppression and utilizes diphenyliodonium chloride to determine if ROS production is altered in response to a mitochondrial electron transport chain inhibitor. Although... mitochondria are thought to be a major source of ROS, literature regarding this theory is inconclusive [37]. Other sites of free radical production have been identified, each generating ROS at levels that may be specific to certain tissues. For instance, Hid...

Henderson, Cara Aletha Everett

2012-06-07T23:59:59.000Z

76

Cytotoxic and DNA-damaging effects of methyl tert-butyl ether and its metabolites on HL-60 cells in vitro  

SciTech Connect (OSTI)

Methyl tert-butyl ether (MTBE) is a widely used oxygenate in unleaded gasoline; however, few studies have been conducted on the toxicity of this compound. This study evaluates the cytotoxic and DNA-damaging effects of MTBE and its metabolites in a human haemopoietic cell line, HL-60. The metabolites of MTBE studied include tertiary butyl alcohol (TBA), {alpha}-hydroxyisobutyric acid (HIBA), and formaldehyde. Comet assay is used to assess DNA damage, and the cytotoxicity is investigated by lactate dehydrogenease (LDH) release. The results show no significant cytotoxic effects of MTBE, TBA, and HIBA over a concentration ranging from 1 to 30 mM. Formaldehyde, in contrast, causes a substantial LDH release at a concentration of 5 {mu}M. Hydrogen peroxide, a known oxidative agent, at concentrations ranging from 10 to 100 {mu}M, produces a significant dose-related increase in DNA damage, whereas a much higher concentration of MTBE (1 to 30 mM) is required to produce a similar observation. The genotoxic effects of TBA and HIBA appear to be identical to that of MTBE. Conversely, DNA damage is observed for formaldehyde at a relatively low concentration range (5 to 100 {mu}M). These findings suggest that MTBE and its metabolites, except formaldehyde, have relatively low cytotoxic and genotoxic effects. 16 refs., 4 figs.

Tang, G.H. [Xian Medical Univ. (China); Shen, Y.; Shen, H.M. [National Univ. of Singapore (Singapore)] [and others

1996-12-31T23:59:59.000Z

77

Imaging the early material response associated with exit surface damage in fused silica  

SciTech Connect (OSTI)

The processes involved at the onset of damage initiation on the surface of fused silica have been a topic of extensive discussion and thought for more than four decades. Limited experimental results have helped develop models covering specific aspects of the process. In this work we present the results of an experimental study aiming at imaging the material response from the onset of the observation of material modification during exposure to the laser pulse through the time point at which material ejection begins. The system involves damage initiation using a 355 nm pulse, 7.8 ns FWHM in duration and imaging of the affected material volume with spatial resolution on the order of 1 {micro}m using as strobe light a 150 ps laser pulse that is appropriately timed with respect to the pump pulse. The observations reveal that the onset of material modification is associated with regions of increased absorption, i.e., formation of an electronic excitation, leading to a reduction in the probe transmission to only a few percent within a time interval of about 1 ns. This area is subsequently rapidly expanding with a speed of about 1.2 {micro}m/ns and is accompanied by the formation and propagation of radial cracks. These cracks appear to initiate about 2 ns after the start of the expansion of the modified region. The damage sites continue to grow for about 25 ns but the mechanism of expansion after the termination of the laser pulse is via formation and propagation of lateral cracks. During this time, the affected area of the surface appears to expand forming a bulge of about 40 {micro}m in height. The first clear observation of material cluster ejection is noted at about 50 ns delay.

Demos, S G; Raman, R N; Negres, R A

2010-11-05T23:59:59.000Z

78

Role of genetic polymorphisms of CYP1A1, CYP3A5, CYP2C9, CYP2D6, and PON1 in the modulation of DNA damage in workers occupationally exposed to organophosphate pesticides  

SciTech Connect (OSTI)

Organophosphate pesticides (OPs) are primarily metabolized by several xenobiotic metabolizing enzymes (XMEs). Very few studies have explored genetic polymorphisms of XMEs and their association with DNA damage in pesticide-exposed workers. The present study was designed to determine the role of genetic polymorphisms of CYP1A1, CYP3A5, CYP2C9, CYP2D6, and PON1 in the modulation of DNA damage in workers occupationally exposed to OPs. We examined 284 subjects including 150 workers occupationally exposed to OPs and 134 normal healthy controls. The DNA damage was evaluated using the alkaline comet assay and genotyping was done using PCR-RFLP. The results revealed that the PONase activity toward paraoxonase and AChE activity was found significantly lowered in workers as compared to control subjects (p < 0.001). Workers showed significantly higher DNA damage compared to control subjects (14.37 {+-} 2.15 vs. 6.24 {+-} 1.37 tail% DNA, p < 0.001). Further, the workers with CYP2D6*3 PM and PON1 (QQ and MM) genotypes were found to have significantly higher DNA damage when compared to other genotypes (p < 0.05). In addition, significant increase in DNA damage was also observed in workers with concomitant presence of certain CYP2D6 and PON1 (Q192R and L55M) genotypes which need further extensive studies. In conclusion, the results indicate that the PON1 and CYP2D6 genotypes can modulate DNA damage elicited by some OPs possibly through gene-environment interactions. -- Highlights: Black-Right-Pointing-Pointer Role of CYP1A1, CYP3A5, CYP2C, CYP2D6 and PON1 genotypes on DNA damage. Black-Right-Pointing-Pointer Workers exposed to some OPs demonstrated increased DNA damage. Black-Right-Pointing-Pointer CYP2D6 *3 PM and PON1 (Q192R and L55M) genotypes are associated with DNA damage. Black-Right-Pointing-Pointer Concomitant presence of certain CYP2D6 and PON1 genotypes can increase DNA damage.

Singh, Satyender [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India)] [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India); Kumar, Vivek [Environmental Biochemistry and Molecular Biology laboratory, Department of Biochemistry, University College of Medical Sciences and GTB Hospital, University of Delhi, Dilshad Garden, Delhi-110095 (India)] [Environmental Biochemistry and Molecular Biology laboratory, Department of Biochemistry, University College of Medical Sciences and GTB Hospital, University of Delhi, Dilshad Garden, Delhi-110095 (India); Vashisht, Kapil; Singh, Priyanka [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India)] [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India); Banerjee, Basu Dev, E-mail: banerjeebd@hotmail.com [Environmental Biochemistry and Molecular Biology laboratory, Department of Biochemistry, University College of Medical Sciences and GTB Hospital, University of Delhi, Dilshad Garden, Delhi-110095 (India); Rautela, Rajender Singh; Grover, Shyam Sunder; Rawat, Devendra Singh; Pasha, Syed Tazeen [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India)] [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India); Jain, Sudhir Kumar [Centre for Epidemiology and Parasitic Diseases, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India)] [Centre for Epidemiology and Parasitic Diseases, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India); Rai, Arvind [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India)] [Division of Biochemistry and Biotechnology, National Centre for Disease Control 22, Sham Nath Marg, Delhi-110054 (India)

2011-11-15T23:59:59.000Z

79

Regulation of epithelial-mesenchymal transition and DNA damage responses by singleminded-2s  

E-Print Network [OSTI]

and progression in breast cancer, we depleted SIM2 RNA in MCF-7 cells using a retroviral shRNA system and examined gene expression and functional abilities of the SIM2-depleted MCF-7 cells (SIM2i) relative to a control MCF line expressing a non-specific “scrambled...

Laffin, Brian Edward

2009-05-15T23:59:59.000Z

80

Telomere Regulation in Arabidopsis thaliana by the CST Capping Complex and DNA Damage Response Proteins  

E-Print Network [OSTI]

). In the flowering plant, Arabidopsis thaliana telomeres are bound by the CST (CTC1/STN1/TEN1) heterotrimer. Loss of any CST component results in telomere shortening, telomere fusions, increased G-overhang length and telomere recombination. To understand...

Boltz, Kara A.

2013-09-11T23:59:59.000Z

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


81

Nonlinear response of plain concrete shear walls with elastic-damaging behavior  

SciTech Connect (OSTI)

This report summarizes the theoretical and computational efforts on the modeling of small scale shear walls. Small scale shear walls are used extensively in the study of shear wall behavior because the construction and testing of full size walls are rather expensive. A finite element code is developed which incorporates nonlinear constitutive relations of damage mechanics. The program is used to obtain nonlinear load-deformation curves and to address the initial loss of stiffness due to shrinkage cracking. The program can also be used to monitor the continuous degradation of the fundamental frequency due to progressive damage.

Yazdani, S.; Schreyer, H.L.

1997-02-01T23:59:59.000Z

82

DNA  

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

September 15, 2014 Computational analysis key to structural understanding of molecular machine that targets viral DNA LOS ALAMOS, N.M., Sept. 15, 2014-When this week's print issue...

83

Chemopreventive activity of compounds extracted from Casearia sylvestris (Salicaceae) Sw against DNA damage induced by particulate matter emitted by sugarcane burning near Araraquara, Brazil  

SciTech Connect (OSTI)

Ethanolic extract of Casearia sylvestris is thought to be antimutagenic. In this study, we attempted to determine whether this extract and casearin X (a clerodane diterpene from C. sylvestris) are protective against the harmful effects of airborne pollutants from sugarcane burning. To that end, we used the Tradescantia micronucleus test in meiotic pollen cells of Tradescantia pallida, the micronucleus test in mouse bone marrow cells, and the comet assay in mouse blood cells. The mutagenic compound was total suspended particulate (TSP) from air. For the Tradescantia micronucleus test, T. pallida cuttings were treated with the extract at 0.13, 0.25, or 0.50 mg/ml. Subsequently, TSP was added at 0.3 mg/ml, and tetrads from the inflorescences were examined for micronuclei. For the micronucleus test in mouse bone marrow cells and the comet assay in mouse blood cells, Balb/c mice were treated for 15 days with the extract—3.9, 7.5, or 15.0 mg/kg body weight (BW)—or with casearin X—0.3, 0.25, or 1.2 mg/kg BW—after which they received TSP (3.75 mg/kg BW). In T. pallida and mouse bone marrow cells, the extract was antimutagenic at all concentrations tested. In mouse blood cells, the extract was antigenotoxic at all concentrations, whereas casearin X was not antimutagenic but was antigenotoxic at all concentrations. We conclude that C. sylvestris ethanolic extract and casearin X protect DNA from damage induced by airborne pollutants from sugarcane burning. -- Highlights: ? We assessed DNA protection of C. sylvestris ethanolic extract. ? We assessed DNA protection of casearin X. ? We used Tradescantia pallida micronucleus test as screening. ? We used comet assay and micronucleus test in mice. ? The compounds protected DNA against sugar cane burning pollutants.

Prieto, A.M. [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Clinical Analysis, Rua Expedicionários do Brasil, 1621, Araraquara (Brazil)] [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Clinical Analysis, Rua Expedicionários do Brasil, 1621, Araraquara (Brazil); Santos, A.G. [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Natural Principles and Toxicology, Rodovia Araraquara-Jau, km 01, Araraquara (Brazil)] [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Natural Principles and Toxicology, Rodovia Araraquara-Jau, km 01, Araraquara (Brazil); Csipak, A.R.; Caliri, C.M.; Silva, I.C. [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Clinical Analysis, Rua Expedicionários do Brasil, 1621, Araraquara (Brazil)] [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Clinical Analysis, Rua Expedicionários do Brasil, 1621, Araraquara (Brazil); Arbex, M.A. [UNIFESP — Federal University of São Paulo, Paulista College of Medicine, Department of Internal Medicine, Rua Pedro de Toledo, 720, São Paulo (Brazil)] [UNIFESP — Federal University of São Paulo, Paulista College of Medicine, Department of Internal Medicine, Rua Pedro de Toledo, 720, São Paulo (Brazil); Silva, F.S.; Marchi, M.R.R. [UNESP — Univ. Estadual Paulista, Chemistry Institute, Department of Analytical Chemistry, Rua Francisco Degni, S/N, Araraquara (Brazil)] [UNESP — Univ. Estadual Paulista, Chemistry Institute, Department of Analytical Chemistry, Rua Francisco Degni, S/N, Araraquara (Brazil); Cavalheiro, A.J.; Silva, D.H.S.; Bolzani, V.S. [UNESP — Univ. Estadual Paulista, Chemistry Institute, Department of Organic Chemistry, Rua Francisco Degni, S/N, Araraquara (Brazil)] [UNESP — Univ. Estadual Paulista, Chemistry Institute, Department of Organic Chemistry, Rua Francisco Degni, S/N, Araraquara (Brazil); Soares, C.P., E-mail: soarescp@hotmail.com [UNESP — Univ. Estadual Paulista, College of Pharmaceutical Sciences, Department of Clinical Analysis, Rua Expedicionários do Brasil, 1621, Araraquara (Brazil)

2012-12-15T23:59:59.000Z

84

Expanded breadth of the T-cell response to mosaic HIV-1 envelope DNA vaccination  

SciTech Connect (OSTI)

An effective AIDS vaccine must control highly diverse circulating strains of HIV-1. Among HIV -I gene products, the envelope (Env) protein contains variable as well as conserved regions. In this report, an informatic approach to the design of T-cell vaccines directed to HIV -I Env M group global sequences was tested. Synthetic Env antigens were designed to express mosaics that maximize the inclusion of common potential Tcell epitope (PTE) 9-mers and minimize the inclusion of rare epitopes likely to elicit strain-specific responses. DNA vaccines were evaluated using intracellular cytokine staining (ICS) in inbred mice with a standardized panel of highly conserved 15-mer PTE peptides. I, 2 and 3 mosaic sets were developed that increased theoretical epitope coverage. The breadth and magnitude ofT-cell immunity stimulated by these vaccines were compared to natural strain Env's; additional comparisons were performed on mutant Env's, including gpl60 or gpl45 with or without V regions and gp41 deletions. Among them, the 2 or 3 mosaic Env sets elicited the optimal CD4 and CD8 responses. These responses were most evident in CD8 T cells; the 3 mosaic set elicited responses to an average of 8 peptide pools compared to 2 pools for a set of3 natural Env's. Synthetic mosaic HIV -I antigens can therefore induce T-cell responses with expanded breadth and may facilitate the development of effective T -cell-based HIV -1 vaccines.

Korber, Bette [Los Alamos National Laboratory; Fischer, William [Los Alamos National Laboratory; Wallstrom, Timothy [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

85

p63 and p73 Transcriptionally Regulate Genes Involved in DNA Repair  

E-Print Network [OSTI]

The p53 family activates many of the same genes in response to DNA damage. Because p63 and p73 have structural differences from p53 and play distinct biological functions in development and metastasis, it is likely that ...

Lin, Yu-Li

86

Tissue responses to low protracted doses of high let radiations or photons: Early and late damage relevant to radio-protective countermeasures  

SciTech Connect (OSTI)

Early and late murine tissue responses to single or fractionated low doses of heavy charged particles, fission-spectrum neutrons or gamma rays are considered. Damage to the hematopoietic system is emphasized, but results on acute lethality, host response to challenge with transplanted leukemia cells and life-shortening are presented. Low dose rates per fraction were used in some neutron experiments. Split-dose lethality studies (LD 50/30) with fission neutrons indicated greater accumulation of injury during a 9 fraction course (over 17 days) than was the case for ..gamma..-radiation. When total doses of 96 or 247 cGy of neutrons or ..gamma.. rays were given as a single dose or in 9 fractions, a significant sparing effect on femur CFU-S depression was observed for both radiation qualities during the first 11 days, but there was not an earlier return to normal with dose fractionation. During the 9 fraction sequence, a significant sparing effect of low dose rate on CFU-S depression was observed in both neutron and ..gamma..-irradiated mice. CFU-S content at the end of the fractionation sequence did not correlate with measured LD 50/30. Sustained depression of femur and spleen CFU-S and a significant thrombocytopenia were observed when a total neutron dose of 240 cGy was given in 72 fractions over 24 weeks at low dose rates. The temporal aspects of CFU-S repopulation were different after a single versus fractionated neutron doses. The sustained reduction in the size of the CFU-S population was accompanied by an increase in the fraction in DNA synthesis. The proliferation characteristics and effects of age were different for radial CFU-S population closely associated with bone, compared with the axial population that can be readily aspirated from the femur. In aged irradiated animals, the CFU-S proliferation/redistribution response to typhoid vaccine showed both an age and radiation effect. 63 refs., 6 figs., 7 tabs.

Ainsworth, E.J.; Afzal, S.M.J.; Crouse, D.A.; Hanson, W.R.; Fry, R.J.M.

1988-01-01T23:59:59.000Z

87

Modeling marrow damage from response data: Morphallaxis from radiation biology to benzene toxicity  

SciTech Connect (OSTI)

Consensus principles from radiation biology were used to describe a generic set of nonlinear, first-order differential equations for modeling of toxicity-induced compensatory cell kinetics in terms of sublethal injury, repair, direct killing, killing of cells with unrepaired sublethal injury, and repopulation. This cellular model was linked to a probit model of hematopoietic mortality that describes death from infection and/or hemorrhage between {approximately} 5 and 30 days. Mortality data from 27 experiments with 851 doseresponse groups, in which doses were protracted by rate and/or fractionation, were used to simultaneously estimate all rate constants by maximum-likelihood methods. Data used represented 18,940 test animals distributed according to: (mice, 12,827); (rats, 2,925); (sheep, 1,676); (swine, 829); (dogs, 479); and (burros, 204). Although a long-term, repopulating hematopoietic stem cell is ancestral to all lineages needed to restore normal homeostasis, the dose-response data from the protracted irradiations indicate clearly that the particular lineage that is ``critical`` to hematopoietic recovery does not resemble stem-like cells with regard to radiosensitivity and repopulation rates. Instead, the weakest link in the chain of hematopoiesis was found to have an intrinsic radioresistance equal to or greater than stromal cells and to repopulate at the same rates. Model validation has been achieved by predicting the LD{sub 50} and/or fractional group mortality in 38 protracted-dose experiments (rats and mice) that were not used in the fitting of model coefficients.

Jones, T.D.; Morris, M.D.; Hasan, J.S.

1995-12-01T23:59:59.000Z

88

Meter Damage: Many customers have questions about who is responsible for repair to the electrical service at their homes. These pages may help to answer  

E-Print Network [OSTI]

Meter Damage: Many customers have questions about who is responsible for repair. weather head stack meter base connectors house knob weather head connectors mast clamp stack meter base meter meter #12; Let's start with definitions: Meter base: This is the metal box mounted

Rose, Annkatrin

89

Species Discovery versus Species Identification in DNA Barcoding Efforts: Response to Rubinoff  

E-Print Network [OSTI]

in the discus- sion. I start with Rubinoff's second point that there are "problems with DNA barcodes and species needs to be tested in a scientific context (Goldstein et al. 2000; Lipscomb et al. 2003; Sites of taxonomy (Dunn 2003; Lipscomb et al. 2003; Seberg et al. 2003). On the other hand DNA sequences can be used

DeSalle, Rob

90

Altered Mitochondrial Retrograde Signaling in Response to mtDNA Depletion or a Ketogenic Diet  

E-Print Network [OSTI]

kinase kinase MCI Mild cognitive impairment MCT Monocarboxylate transporter Mfn Mitofusin mtDNA Mitochondrial DNA mTOR Mammalian target of rapamycin mTORC1 mTOR complex 1 MRC Mitochondrial Respiratory Complex NAD(H) Nicotinamide adenine...

Selfridge, Jennifer Eva

2012-12-31T23:59:59.000Z

91

Cell cycle and DNA damage response regulation by Spy1, and the intersection of FGFR and NFkappaB pathways  

E-Print Network [OSTI]

regulates the synthesis of the CIP/KIP family of CDKCKIs), specifically p21 CIP and p27 KIP , which negativelyB, CDC25C activity, and p21 CIP levels, which are controlled

McAndrew, Christopher William

2010-01-01T23:59:59.000Z

92

Analysis of Flow Cytometry DNA Damage Response Protein Activation Kinetics Following X-rays and High Energy Iron Nuclei Exposure  

E-Print Network [OSTI]

software (TreeStar Inc. , Ashland, OR. ) and analyzed assoftware (TreeStar Inc. , Ashland, OR. ) and resulting

Chappell, Lori J.

2011-01-01T23:59:59.000Z

93

Cell cycle and DNA damage response regulation by Spy1, and the intersection of FGFR and NFkappaB pathways  

E-Print Network [OSTI]

Silva LF, Duncker BP. ORC function in late G1: maintaining128-30. DePamphilis ML. The 'ORC cycle': a novel pathway forOrigin Recognition Complex (ORC), cdc6/18, cdc45, cdt1, the

McAndrew, Christopher William

2010-01-01T23:59:59.000Z

94

Functional role of p53 N-terminal phosphorylation in regulating the p53 response to DNA damage  

E-Print Network [OSTI]

M. T. , Joseloff, E. , Milczarek, G. , and Bowden, G. T. (M. T. , Joseloff, E. , Milczarek, G. , and Bowden, G. T. (

Chao, Connie

2006-01-01T23:59:59.000Z

95

ATM Phosphorylates and Activates the Transcription Factor MEF2D for Neuronal Survival in Response to DNA Damage  

E-Print Network [OSTI]

Biol. , 4, Schwartz E. I. , Smilenov L. B. , Price M. A. ,FEBS Lett. , 472, 53-56. Smilenov L. B. , Morgan S. E. ,Metcalfe et al. , 1996; Smilenov et al. , 1997). Cancer

Chan, Shing Fai

2009-01-01T23:59:59.000Z

96

Comment on `Nanoconfinement-enhanced conformational response of single DNA molecules to changes in ionic environment'  

E-Print Network [OSTI]

In the present Comment we show that, contrary to the recent findings of Reisner et al. [Phys. Rev. Lett. 99, 058302 (2007)], the excluded volume effect does not play an important role in determining DNA behavior in nanochannels at low ionic strength. We argue that the DNA extension data are described very well without the notion of an effective polymer width using the entropic depletion theory due to Odijk.

Madhavi Krishnan; Eugene P. Petrov

2008-05-14T23:59:59.000Z

97

Time-resolved imaging of material response during laser-induced bulk damage in SiO2  

SciTech Connect (OSTI)

We report on time resolved imaging of the dynamic events taking place during laser-induced damage in the bulk of fused silica samples with nanosecond temporal resolution and one micron spatial resolution. These events include: shock/pressure wave formation and propagation, transient absorption, crack propagation and formation of residual stress fields. The work has been performed using a time-resolved microscope system that utilizes a probe pulse to acquire images at delay times covering the entire timeline of a damage event. Image information is enhanced using polarized illumination and simultaneously recording the two orthogonal polarization image components. For the case of fused silica, an electronic excitation is first observed accompanied by the onset of a pressure wave generation and propagation. Cracks are seen to form early in the process and reach their final size at about 25 ns into the damage event. In addition, changes that in part are attributed to transient absorption in the modified material are observed for delays up to about 200 microseconds.

Demos, S G; Negres, R A

2008-10-24T23:59:59.000Z

98

DNA Repair 8 (2009) 803812 Contents lists available at ScienceDirect  

E-Print Network [OSTI]

reduced gap repair and loss of the checkpoint response to low-dose irradiation. These findings shed light. Loss of the FHA domain resulted in hypersensitivity to ionizing radiation and defects in gap repair time for repair pro- cesses to act. A given DNA damage response protein may be involved Corresponding

Sekelsky, Jeff

99

Protein Bridges DNA Base and Nucleotide Excision Repair Pathways  

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

a nucleotide from the DNA double helix to its active site to access damaged nucleotides. But unlike AGT and most other known DNA nucleotide-flipping proteins, this...

100

Guest Editorial: Laser Damage  

SciTech Connect (OSTI)

Laser damage of optical materials, first reported in 1964, continues to limit the output energy and power of pulsed and continuous-wave laser systems. In spite of some 48 years of research in this area, interest from the international laser community to laser damage issues remains at a very high level and does not show any sign of decreasing. Moreover, it grows with the development of novel laser systems, for example, ultrafast and short-wavelength lasers that involve new damage effects and specific mechanisms not studied before. This interest is evident from the high level of attendance and presentations at the annual SPIE Laser Damage Symposium (aka, Boulder Damage Symposium) that has been held in Boulder, Colorado, since 1969. This special section of Optical Engineering is the first one devoted to the entire field of laser damage rather than to a specific part. It is prepared in response to growing interest from the international laser-damage community. Some papers in this special section were presented at the Laser Damage Symposium; others were submitted in response to the general call for papers for this special section. The 18 papers compiled into this special section represent many sides of the broad field of laser-damage research. They consider theoretical studies of the fundamental mechanisms of laser damage including laser-driven electron dynamics in solids (O. Brenk and B. Rethfeld; A. Nikiforov, A. Epifanov, and S. Garnov; T. Apostolova et al.), modeling of propagation effects for ultrashort high-intensity laser pulses (J. Gulley), an overview of mechanisms of inclusion-induced damage (M. Koldunov and A. Manenkov), the formation of specific periodic ripples on a metal surface by femtosecond laser pulses (M. Ahsan and M. Lee), and the laser-plasma effects on damage in glass (Y. Li et al). Material characterization is represented by the papers devoted to accurate and reliable measurements of absorption with special emphasis on thin films (C. Mühlig and S. Bublitz; B. Cho, E. Danielewicz, and J. Rudisill; W. Palm et al; and J. Lu et al.). Statistical treatment of measurements of the laser-damage threshold (J. Arenberg) and the relationship to damage mechanisms (F. Wagner et al.) represent the large subfield of laser-damage measurements. Various aspects of multilayer coating and thin-film characterization are considered in papers by B. Cho, J. Rudisill, and E. Danielewicz (spectral shift in multilayer mirrors) and R. Weber et al. (novel approach to damage studies based on third-harmonic generation microscopy). Of special interest for readers is the paper by C. Stolz that summarizes the results of four “thin-film damage competitions” organized as a part of the Laser Damage Symposium. Another paper is devoted to thermal annealing of damage precursors (N. Shen et al.). Finally, the influence of nano-size contamination on initiation of laser damage by ultrashort pulses is considered in paper of V. Komolov et al.

Vitaly Gruzdev, Michelle D. Shinn

2012-12-01T23:59:59.000Z

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


101

Human AlkB Homolog ABH8 Is a tRNA Methyltransferase Required for Wobble Uridine Modification and DNA Damage Survival  

E-Print Network [OSTI]

tRNA nucleosides are extensively modified to ensure their proper function in translation. However, many of the enzymes responsible for tRNA modifications in mammals await identification. Here, we show that human AlkB homolog ...

Fu, Dragony

102

Strandwise translocation of a DNA glycosylase on undamaged DNA  

SciTech Connect (OSTI)

Base excision repair of genotoxic nucleobase lesions in the genome is critically dependent upon the ability of DNA glycosylases to locate rare sites of damage embedded in a vast excess of undamaged DNA, using only thermal energy to fuel the search process. Considerable interest surrounds the question of how DNA glycosylases translocate efficiently along DNA while maintaining their vigilance for target damaged sites. Here, we report the observation of strandwise translocation of 8-oxoguanine DNA glycosylase, MutM, along undamaged DNA. In these complexes, the protein is observed to translocate by one nucleotide on one strand while remaining untranslocated on the complementary strand. We further report that alterations of single base-pairs or a single amino acid substitution (R112A) can induce strandwise translocation. Molecular dynamics simulations confirm that MutM can translocate along DNA in a strandwise fashion. These observations reveal a previously unobserved mode of movement for a DNA-binding protein along the surface of DNA.

Qi, Yan; Nam, Kwangho; Spong, Marie C.; Banerjee, Anirban; Sung, Rou-Jia; Zhang, Michael; Karplus, Martin; Verdine, Gregory L. (Harvard)

2012-05-14T23:59:59.000Z

103

Infection-induced colitis in mice causes dynamic and tissue-specific changes in stress response and DNA damage leading to colon cancer  

E-Print Network [OSTI]

Helicobacter hepaticus-infected Rag2-/- mice emulate many aspects of human inflammatory bowel disease, including the development of colitis and colon cancer. To elucidate mechanisms of inflammation-induced carcinogenesis, ...

Mangerich, Aswin

104

A General Method for Quantifying Sequence Effects on Nucleobase Oxidation in DNA  

E-Print Network [OSTI]

Oxidative damage to DNA has long been associated with aging and disease, with guanine serving as the

Margolin, Yelena

2010-01-01T23:59:59.000Z

105

Local chromatin structure of heterochromatin regulates repeatedDNA stability, nucleolus structure, and genome integrity  

SciTech Connect (OSTI)

Heterochromatin constitutes a significant portion of the genome in higher eukaryotes; approximately 30% in Drosophila and human. Heterochromatin contains a high repeat DNA content and a low density of protein-encoding genes. In contrast, euchromatin is composed mostly of unique sequences and contains the majority of single-copy genes. Genetic and cytological studies demonstrated that heterochromatin exhibits regulatory roles in chromosome organization, centromere function and telomere protection. As an epigenetically regulated structure, heterochromatin formation is not defined by any DNA sequence consensus. Heterochromatin is characterized by its association with nucleosomes containing methylated-lysine 9 of histone H3 (H3K9me), heterochromatin protein 1 (HP1) that binds H3K9me, and Su(var)3-9, which methylates H3K9 and binds HP1. Heterochromatin formation and functions are influenced by HP1, Su(var)3-9, and the RNA interference (RNAi) pathway. My thesis project investigates how heterochromatin formation and function impact nuclear architecture, repeated DNA organization, and genome stability in Drosophila melanogaster. H3K9me-based chromatin reduces extrachromosomal DNA formation; most likely by restricting the access of repair machineries to repeated DNAs. Reducing extrachromosomal ribosomal DNA stabilizes rDNA repeats and the nucleolus structure. H3K9me-based chromatin also inhibits DNA damage in heterochromatin. Cells with compromised heterochromatin structure, due to Su(var)3-9 or dcr-2 (a component of the RNAi pathway) mutations, display severe DNA damage in heterochromatin compared to wild type. In these mutant cells, accumulated DNA damage leads to chromosomal defects such as translocations, defective DNA repair response, and activation of the G2-M DNA repair and mitotic checkpoints that ensure cellular and animal viability. My thesis research suggests that DNA replication, repair, and recombination mechanisms in heterochromatin differ from those in euchromatin. Remarkably, human euchromatin and fly heterochromatin share similar features; such as repeated DNA content, intron lengths and open reading frame sizes. Human cells likely stabilize their DNA content via mechanisms and factors similar to those in Drosophila heterochromatin. Furthermore, my thesis work raises implications for H3K9me and chromatin functions in complex-DNA genome stability, repeated DNA homogenization by molecular drive, and in genome reorganization through evolution.

Peng, Jamy C.

2007-05-05T23:59:59.000Z

106

Nanotechnology with DNA DNA Nanodevices  

E-Print Network [OSTI]

Nanotechnology with DNA DNA Nanodevices Friedrich C. Simmel* and Wendy U. Dittmer A DNA actuator. Introduction.............285 2. Overview: DNA Nanotechnology.......285 3. Prototypes of Nanomechanical DNA overview of DNA nanotechnology as a whole is given. The most important properties of DNA molecules

Ludwig-Maximilians-Universität, München

107

Replication protein A and g-H2AX foci assembly is triggered by cellular response to DNA double-strand breaks  

E-Print Network [OSTI]

pathway that removes the oxidized base lesions from the genomic DNA [6]. Evidence for the stimulation

108

E-Print Network 3.0 - active dna replication Sample Search Results  

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

DnaB(Ts), we examined the degradation... of the DnaB Helicase Leads to the Collapse and Degradation of the Replication Fork: a Comparison to UV... -induced DNA damage and...

109

Damage experiments in a cylindrical geometry  

SciTech Connect (OSTI)

Studying spallation damage with a cylindrical configuration allows for a natural recollection of the damaged material under proper driving conditions. Additionally, the damaged material can come to a complete rest without the application of further stopping forces. Specific areas of research include the damage initiation regime in convergent geometry, behavior of material recollected after damage, and effects of convergent geometry on the material response. Such experiments produce unique strain and shear stress states, motivating improvements in existing computational material models and increasing the predictive capabilities of codes. A LANL/VNIIEF joint experimental series has produced cylindrical aluminum failure initiation data and studied the behavior of material recollected after damage initiation and after complete failure. In addition to post-shot collection of the damaged target material for subsequent metallographic analysis, dynamic in-situ experimental diagnostics include velocimetry and transverse radial radiography. This paper will discuss the current experimental status.

Kaul, Ann M [Los Alamos National Laboratory

2010-09-21T23:59:59.000Z

110

Environmental Stigma Damages: Speculative Damages in Environmental Tort Cases  

E-Print Network [OSTI]

contami- nation causing environmental damage cannot be seen,Damages: Speculative Damages in Environmental Tort Cases E.in cases of environmental damage, primar- ily because it is

Johnson, E. Jean

1997-01-01T23:59:59.000Z

111

Role of DNA repair protein ERCC1 in skin cancer   

E-Print Network [OSTI]

Nucleotide excision repair (NER) is one of the major repair systems for removal of DNA lesions. The NER pathway has evolved mainly to repair UV-induced DNA damage and is also active against a broad range of endogenously ...

Song, Liang

2009-01-01T23:59:59.000Z

112

SUBSPACE-BASED DETECTION OF FATIGUE DAMAGE ON JACKET SUPPORT STRUCTURES OF OFFSHORE WIND TURBINES  

E-Print Network [OSTI]

SUBSPACE-BASED DETECTION OF FATIGUE DAMAGE ON JACKET SUPPORT STRUCTURES OF OFFSHORE WIND TURBINES damage in real size structural components of offshore wind turbines. KEYWORDS : Damage detection, Offshore wind turbines, Numerical response simulation. INTRODUCTION Offshore wind turbines are exposed

Paris-Sud XI, Université de

113

Damage susceptibility tables  

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

conditions, 3) that x-ray induced damage rates for a common material (relatively pure PVC in this example 7,8 ) can be used to normalize different sets of XPS damage...

114

DNA demethylation by DNA repair  

E-Print Network [OSTI]

Active DNA demethylation underlies key facets of reproduction in flowering plants and mammals and serves a general genome housekeeping function in plants. A family of 5-methylcytosine DNA glycosylases catalyzes plant ...

Gehring, Mary

115

E-Print Network 3.0 - asynchronous dna replication Sample Search...  

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

08.00 0 doi:10.1128JB.00408-07 Summary: of the DnaB Helicase Leads to the Collapse and Degradation of the Replication Fork: a Comparison to UV... -induced DNA damage and...

116

E-Print Network 3.0 - affect dna replication Sample Search Results  

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

08.00 0 doi:10.1128JB.00408-07 Summary: of the DnaB Helicase Leads to the Collapse and Degradation of the Replication Fork: a Comparison to UV... -induced DNA damage and...

117

E-Print Network 3.0 - accurate dna copy Sample Search Results  

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

08.00 0 doi:10.1128JB.00408-07 Summary: of the DnaB Helicase Leads to the Collapse and Degradation of the Replication Fork: a Comparison to UV... -induced DNA damage and...

118

Applicability of linear analysis in probabilistic estimation of seismic building damage to reinforced-concrete structures  

E-Print Network [OSTI]

As design has moved from strength based to performance based, there has been an effort to relate building response to damage. Because decision-makers typically consider human lives, property damage and cost, setting ...

James, Timothy P. (Timothy Philip)

2012-01-01T23:59:59.000Z

119

Nondestructive Damage Detection in General Beams  

E-Print Network [OSTI]

is to provide NDE methodologies that simultaneously identify the location, the extent, and the severity of damage in general beams. By general beams, we mean beyond Euler-Bernoulli beams (i.e. slender beams) to deep beams and stubby beams whose response may...

Dincal, Selcuk

2010-12-08T23:59:59.000Z

120

Controlling Beaver Damage  

E-Print Network [OSTI]

Beavers are important because their dams stabilize creek flow, slow runoff and create ponds. However, these same dams can negatively alter the flow of creeks. Damage prevention, control and various trapping methods are discussed in this publication....

Texas Wildlife Services

2007-03-13T23:59:59.000Z

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


121

Controlling Opossum Damage  

E-Print Network [OSTI]

damage; however, their pelts can be sold only during the furbearer season and with the proper licenses. Other furbearers include beaver, otter, mink, nutria, ringtailed cat, badger, skunk, weasel, raccoon, muskrat, fox and civet cat. Homeowners...

Texas Wildlife Services

2007-05-23T23:59:59.000Z

122

Composite heat damage assessment  

SciTech Connect (OSTI)

The effects of heat damage were determined on the residual mechanical, physical, and chemical properties of IM6/3501-6 laminates, and potential nondestructive techniques to detect and assess material heat damage were evaluated. About one thousand preconditioned specimens were exposed to elevated temperatures, then cooled to room temperature and tested in compression, flexure, interlaminar shear, shore-D hardness, weight loss, and change in thickness. Specimens experienced significant and irreversible reduction in their residual properties when exposed to temperatures exceeding the material upper service temperature of this material (350{degrees}F). The Diffuse Reflectance Infrared Fourier Transform and Laser-Pumped Fluorescence techniques were found to be capable of rapid, in-service, nondestructive detection and quantitation of heat damage in IM6/3501- 6. These techniques also have the potential applicability to detect and assess heat damage effects in other polymer matrix composites.

Janke, C.J.; Wachter, E.A. [Oak Ridge National Lab., TN (United States); Philpot, H.E. [Oak Ridge K-25 Site, TN (United States); Powell, G.L. [Oak Ridge Y-12 Plant, TN (United States)

1993-12-31T23:59:59.000Z

123

Application of Damage Detection Techniques Using Wind Turbine Modal Data  

SciTech Connect (OSTI)

As any structure ages, its structural characteristics will also change. The goal of this work was to determine if modal response data fkom a wind turbine could be used in the detection of damage. The input stimuli to the wind turbine were from traditional modal hammer input and natural wind excitation. The structural response data was acquired using accelerometers mounted on the rotor of a parked and undamaged horizontal-axis wind turbine. The bolts at the root of one of the three blades were then loosened to simulate a damaged blade. The structural response data of the rotor was again recorded. The undamaged and damage-simulated datasets were compared using existing darnage detection algorithms. Also, a novel algorithm for combining the results of different damage detection algorithms was utilized in the assessment of the data. This paper summarizes the code development and discusses some preliminary damage detection results.

Gross, E.; Rumsey, M.; Simmermacher, T.; Zadoks, R.I.

1998-12-17T23:59:59.000Z

124

Atomistic simulations of radiation damage in amorphous metal alloys  

E-Print Network [OSTI]

While numerous fundamental studies have characterized the atomic-level radiation response mechanisms in irradiated crystalline alloys, comparatively little is known regarding the mechanisms of radiation damage in amorphous ...

Baumer, Richard E. (Richard Edward)

2013-01-01T23:59:59.000Z

125

Graded Materials for Resistance to Contact Deformation and Damage  

E-Print Network [OSTI]

Graded Materials for Resistance to Contact Deformation and Damage S. Suresh The mechanical response as diverse as tribology, geology, optoelectronics, biomechanics, fracture mechanics, and nanotechnology changes in the elastic properties of sands, soils, and rocks beneath Earth's surface in- fluence

Suresh, Subra

126

Oxidative dealkylation DNA repair mediated by the mononuclear non-heme iron AlkB proteins  

E-Print Network [OSTI]

to nonenzymatic alkylation (methylation) by environmental or chemical mutagens, resulting in adducts Abstract DNA can be damaged by various intracellular and environmental alkylating agents to produce to diseases such as cancer. Recently, it was discovered that some of the alkylation DNA base damage can

He, Chuan

127

Oxidative stress and oxidative damage in chemical carcinogenesis  

SciTech Connect (OSTI)

Reactive oxygen species (ROS) are induced through a variety of endogenous and exogenous sources. Overwhelming of antioxidant and DNA repair mechanisms in the cell by ROS may result in oxidative stress and oxidative damage to the cell. This resulting oxidative stress can damage critical cellular macromolecules and/or modulate gene expression pathways. Cancer induction by chemical and physical agents involves a multi-step process. This process includes multiple molecular and cellular events to transform a normal cell to a malignant neoplastic cell. Oxidative damage resulting from ROS generation can participate in all stages of the cancer process. An association of ROS generation and human cancer induction has been shown. It appears that oxidative stress may both cause as well as modify the cancer process. Recently association between polymorphisms in oxidative DNA repair genes and antioxidant genes (single nucleotide polymorphisms) and human cancer susceptibility has been shown.

Klaunig, James E., E-mail: jklauni@indiana.edu; Wang Zemin; Pu Xinzhu; Zhou Shaoyu

2011-07-15T23:59:59.000Z

128

Comparative Analysis of Four Oxidized Guanine Lesions from Reactions of DNA with Peroxynitrite, Singlet Oxygen, and ?-Radiation  

E-Print Network [OSTI]

Oxidative damage to DNA has many origins, including irradiation, inflammation, and oxidative stress, but the chemistries are not the same. The most oxidizable base in DNA is 2-deoxyguanosine (dG), and the primary oxidation ...

Cui, Liang

129

Quercitrin protects skin from UVB-induced oxidative damage  

SciTech Connect (OSTI)

Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin. - Highlights: • Oxidative stress plays a key role in UV-induced cell and tissue injuries. • Quercitrin decreases ROS generation and restores antioxidants irradiated by UVB. • Quercitrin reduces UVB-irradiated oxidative DNA damage, apoptosis, and inflammation. • Quercitrin functions as an antioxidant against UVB-induced skin injuries.

Yin, Yuanqin [Cancer Institute, The First Affiliated Hospital, China Medical University, Shenyang (China); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Li, Wenqi; Son, Young-Ok; Sun, Lijuan; Lu, Jian; Kim, Donghern; Wang, Xin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Yao, Hua [Department of Stomatology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang (China); Wang, Lei; Pratheeshkumar, Poyil; Hitron, Andrew J. [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Luo, Jia [Department of Internal Medicine, University of Kentucky, 800 Rose Street, Lexington, KY (United States); Gao, Ning [Department of Pharmacognos, College of Pharmacy, 3rd Military Medical University, Chongqing (China); Shi, Xianglin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States); Zhang, Zhuo, E-mail: zhuo.zhang@uky.edu [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY (United States)

2013-06-01T23:59:59.000Z

130

Damage-induced nonassociated inelastic flow in rock salt  

SciTech Connect (OSTI)

The multi-mechanism deformation coupled fracture model recently developed by CHAN, et al. (1992), for describing time-dependent, pressure-sensitive inelastic flow and damage evolution in crystalline solids was evaluated against triaxial creep experiments on rock salt. Guided by experimental observations, the kinetic equation and the flow law for damage-induced inelastic flow in the model were modified to account for the development of damage and inelastic dilatation in the transient creep regime. The revised model was then utilized to obtain the creep response and damage evolution in rock salt as a function of confining pressure and stress difference. Comparison between model calculation and experiment revealed that damage-induced inelastic flow is nonassociated, dilatational, and contributes significantly to the macroscopic strain rate observed in rock salt deformed at low confining pressures. The inelastic strain rate and volumetric strain due to damage decrease with increasing confining pressures, and all are suppressed at sufficiently high confining pressures.

Chan, K.S.; Bodner, S.R. [Southwest Research Inst., San Antonio, TX (United States); Brodsky, N.S.; Fossum, A.F. [RE/SPEC, Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

1993-06-01T23:59:59.000Z

131

8-Oxoguanine DNA glycosylase 1 (ogg1) maintains the function of cardiac progenitor cells during heart formation in zebrafish  

SciTech Connect (OSTI)

Genomic damage may devastate the potential of progenitor cells and consequently impair early organogenesis. We found that ogg1, a key enzyme initiating the base-excision repair, was enriched in the embryonic heart in zebrafish. So far, little is known about DNA repair in cardiogenesis. Here, we addressed the critical role of ogg1 in cardiogenesis for the first time. ogg1 mainly expressed in the anterior lateral plate mesoderm (ALPM), the primary heart tube, and subsequently the embryonic myocardium by in situ hybridisation. Loss of ogg1 resulted in severe cardiac morphogenesis and functional abnormalities, including the short heart length, arrhythmia, decreased cardiomyocytes and nkx2.5{sup +} cardiac progenitor cells. Moreover, the increased apoptosis and repressed proliferation of progenitor cells caused by ogg1 deficiency might contribute to the heart phenotype. The microarray analysis showed that the expression of genes involved in embryonic heart tube morphogenesis and heart structure were significantly changed due to the lack of ogg1. Among those, foxh1 is an important partner of ogg1 in the cardiac development in response to DNA damage. Our work demonstrates the requirement of ogg1 in cardiac progenitors and heart development in zebrafish. These findings may be helpful for understanding the aetiology of congenital cardiac deficits. - Highlights: • A key DNA repair enzyme ogg1 is expressed in the embryonic heart in zebrafish. • We found that ogg1 is essential for normal cardiac morphogenesis in zebrafish. • The production of embryonic cardiomyocytes requires appropriate ogg1 expression. • Ogg1 critically regulated proliferation of cardiac progenitor cells in zebrafish. • foxh1 is a partner of ogg1 in the cardiac development in response to DNA damage.

Yan, Lifeng [State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 210029 (China); Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 210029 (China); Zhou, Yong [Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Yu, Shanhe [Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200025 (China); Ji, Guixiang [Nanjing Institute of Environmental Sciences/Key Laboratory of Pesticide Environmental Assessment and Pollution Control, Ministry of Environmental Protection, Nanjing 210042 (China); Wang, Lei [Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Liu, Wei [State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 210029 (China); Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 210029 (China); Gu, Aihua, E-mail: aihuagu@njmu.edu.cn [State Key Laboratory of Reproductive Medicine, Institute of Toxicology, Nanjing Medical University, Nanjing 210029 (China); Key Laboratory of Modern Toxicology of Ministry of Education, School of Public Health, Nanjing Medical University, Nanjing 210029 (China)

2013-11-15T23:59:59.000Z

132

Regulation with anticipated learning about environmental damages  

E-Print Network [OSTI]

abatement costs and environmental damages, and a generalemissions. 2.2 Environmental damages and learning Let S t begas stocks and environmental damages. In some respects these

Karp, L; Zhang, J

2006-01-01T23:59:59.000Z

133

Cisplatin-induced nucleosome and RNA polymerase II modification mediate cellular response to the drug  

E-Print Network [OSTI]

(cont.) with recombinant material. The in vitro system established in this study will facilitate the investigation of platinum-DNA damage by DNA repair processes and help elucidate the role of specific post-translational ...

Wang, Dong, 1975-

2004-01-01T23:59:59.000Z

134

Ectopic ERK Expression Induces Phenotypic Conversion of C10 Cells and Alters DNA Methyltransferase Expression  

SciTech Connect (OSTI)

In some model systems constitutive extracellular signal regulated kinase (ERK) activation is sufficient to promote an oncogenic phenotype. Here we investigate whether constitutive ERK expression influences phenotypic conversion in murine C10 type II alveolar epithelial cells. C10 cells were stably transduced with an ERK1-green fluorescent protein (ERK1-GFP) chimera or empty vector and ectopic ERK expression was associated with the acquisition of soft agar focus-forming potential in late passage, but not early passage cells. Late passage ERK1-GFP cells exhibited a significant increase in the expression of DNA methyl transferases (DNMT1 and 3b) and a marked increase in sensitivity to 5-azacytidine (5-azaC)-mediated toxicity, relative to early passage ERK1-GFP cells and vector controls. The expression of xeroderma pigmentosum complementation group A (XPA) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) were significantly increased in late passage cells, suggesting enhanced DNA damage recognition and repair activity which we interpret as a reflection of genomic instability. Phospho-ERK levels were dramatically decreased in late passage ERK1-GFP cells, relative to early passage and vector controls, and phospho-ERK levels were restored by treatment with sodium orthovanadate, indicating a role for phosphatase activity in this response. Collectively these observations suggest that ectopic ERK expression promotes phenotypic conversion of C10 cells that is associated with latent effects on epigenetic programming and phosphatase activities.

Sontag, Ryan L.; Weber, Thomas J.

2012-05-04T23:59:59.000Z

135

Microfluidic DNA sample preparation method and device  

DOE Patents [OSTI]

Manipulation of DNA molecules in solution has become an essential aspect of genetic analyses used for biomedical assays, the identification of hazardous bacterial agents, and in decoding the human genome. Currently, most of the steps involved in preparing a DNA sample for analysis are performed manually and are time, labor, and equipment intensive. These steps include extraction of the DNA from spores or cells, separation of the DNA from other particles and molecules in the solution (e.g. dust, smoke, cell/spore debris, and proteins), and separation of the DNA itself into strands of specific lengths. Dielectrophoresis (DEP), a phenomenon whereby polarizable particles move in response to a gradient in electric field, can be used to manipulate and separate DNA in an automated fashion, considerably reducing the time and expense involved in DNA analyses, as well as allowing for the miniaturization of DNA analysis instruments. These applications include direct transport of DNA, trapping of DNA to allow for its separation from other particles or molecules in the solution, and the separation of DNA into strands of varying lengths.

Krulevitch, Peter A. (Pleasanton, CA); Miles, Robin R. (Danville, CA); Wang, Xiao-Bo (San Diego, CA); Mariella, Raymond P. (Danville, CA); Gascoyne, Peter R. C. (Bellaire, TX); Balch, Joseph W. (Livermore, CA)

2002-01-01T23:59:59.000Z

136

Radiation damage tolerant nanomaterials  

E-Print Network [OSTI]

Designing a material from the atomic level to achieve a tailored response in extreme conditions is a grand challenge in materials research. Nanostructured metals and composites provide a path to this goal because they ...

Beyerlein, I.J.

137

One-electron Oxidation of a Pyrenyl Photosensitizer Covalently Attached to DNA and Competition Between its Further Oxidation and DNA Hole Injection  

E-Print Network [OSTI]

The photosensitized hole injection and guanine base damage phenomena have been investigated in the DNA sequence, 5?-d(CATG[subscript 1] [superscript Py]CG[subscript 2]TCCTAC) with a site-specifically positioned pyrene-like ...

Yun, Byeong Hwa

138

Nucleotide capacitance calculation for DNA sequencing  

SciTech Connect (OSTI)

Using a first-principles linear response theory, the capacitance of the DNA nucleotides, adenine, cytosine, guanine and thymine, are calculated. The difference in the capacitance between the nucleotides is studied with respect to conformational distortion. The result suggests that although an alternate current capacitance measurement of a single-stranded DNA chain threaded through a nano-gap electrodes may not sufficient to be used as a stand alone method for rapid DNA sequencing, the capacitance of the nucleotides should be taken into consideration in any GHz-frequency electric measurements and may also serve as an additional criterion for identifying the DNA sequence.

Lu, Jun-Qiang [ORNL; Zhang, Xiaoguang [ORNL

2008-01-01T23:59:59.000Z

139

Diphenylarsinic acid, a chemical warfare-related neurotoxicant, promotes liver carcinogenesis via activation of aryl hydrocarbon receptor signaling and consequent induction of oxidative DAN damage in rats  

SciTech Connect (OSTI)

Diphenylarsinic acid (DPAA), a chemical warfare-related neurotoxic organic arsenical, is present in the groundwater and soil in some regions of Japan due to illegal dumping after World War II. Inorganic arsenic is carcinogenic in humans and its organic arsenic metabolites are carcinogenic in animal studies, raising serious concerns about the carcinogenicity of DPAA. However, the carcinogenic potential of DPAA has not yet been evaluated. In the present study we found that DPAA significantly enhanced the development of diethylnitrosamine-induced preneoplastic lesions in the liver in a medium-term rat liver carcinogenesis assay. Evaluation of the expression of cytochrome P450 (CYP) enzymes in the liver revealed that DPAA induced the expression of CYP1B1, but not any other CYP1, CYP2, or CYP3 enzymes, suggesting that CYP1B1 might be the enzyme responsible for the metabolic activation of DPAA. We also found increased oxidative DNA damage, possibly due to elevated CYP1B1 expression. Induction of CYP1B1 has generally been linked with the activation of AhR, and we found that DPAA activates the aryl hydrocarbon receptor (AhR). Importantly, the promotion effect of DPAA was observed only at a dose that activated the AhR, suggesting that activation of AhR and consequent induction of AhR target genes and oxidative DNA damage plays a vital role in the promotion effects of DPAA. The present study provides, for the first time, evidence regarding the carcinogenicity of DPAA and indicates the necessity of comprehensive evaluation of its carcinogenic potential using long-term carcinogenicity studies. - Highlights: • DPAA, an environmental neurotoxicant, promotes liver carcinogenesis in rats. • DPAA is an activator of AhR signaling pathway. • DPAA promoted oxidative DNA damage in rat livers. • AhR target gene CYP 1B1 might be involved in the metabolism of DPAA.

Wei, Min; Yamada, Takanori; Yamano, Shotaro; Kato, Minoru; Kakehashi, Anna; Fujioka, Masaki; Tago, Yoshiyuki; Kitano, Mistuaki; Wanibuchi, Hideki, E-mail: wani@med.osaka-cu.ac.jp

2013-11-15T23:59:59.000Z

140

Treatment of anisotropic damage development within a scalar damage formulation  

SciTech Connect (OSTI)

This paper is concerned with describing a damage mechanics formulation which provides for non-isotropic effects using a scalar damage variable. An investigation has been in progress for establishing the constitutive behavior of rock salt at long times and low to moderate confining pressures in relation to the possible use of excavated rooms in rock salt formations as repositories for nuclear waste. An important consideration is the effect of damage manifested principally by the formation of shear induced wing cracks which have a stress dependent orientation. The analytical formulation utilizes a scalar damage parameter, but is capable of indicating the non- isotropic dependence of inelastic straining on the stress state and the confining pressure. Also, the equations indicate the possibility of volumetric expansions leading to the onset of tertiary creep and eventually rupture if the damage variable reaches a critical value.

Chan, K.S. [Southwest Research Inst., San Antonio, TX (United States); Bodner, S.R. [Southwest Research Inst., San Antonio, TX (United States)][Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Mechanical Engineering; Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

1996-11-01T23:59:59.000Z

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


141

LONG-CIRCULATING DNA LIPID NANOCAPSULES AS NEW VECTOR FOR PASSIVE TUMOR , Montier T.  

E-Print Network [OSTI]

genetic material to target cells. To this end, DNA, complexed with cationic lipids i.e DOTAP causing any hepatic damage. Keywords: poly (ethylene glycol) - non-viral vector - stealth properties

Paris-Sud XI, Université de

142

Mechanisms that prevent DNA re-replication in the yeast Saccharomyces cerevisiae  

E-Print Network [OSTI]

Every time a cell divides it must faithfully duplicate its genome before the cell divides. If replication initiates a second time (re-replication) before cytokinesis, cells can accumulate extensive DNA damage, which results ...

Tanny, Robyn E

2006-01-01T23:59:59.000Z

143

Asiakastyytyväisyystutkimus - DNA Kauppa Lappeenranta.  

E-Print Network [OSTI]

??Opinnäytetyön aiheena oli DNA Kauppa Lappeenrannan asiakastyytyväisyyden tutkiminen. Tutkimuksen ensisijaisena tavoitteena oli selvittää, kuinka tyytyväisiä asiakkaat olivat olleet DNA Kauppa Lappeenrannan ja asiakkaan väliseen kontaktipintaan… (more)

Pitkänen, Jesse

2013-01-01T23:59:59.000Z

144

XRCC1 & DNA MTases : direct and indirect modulation of inflammation-induced DNA damage  

E-Print Network [OSTI]

Cancer causes 13% of all deaths worldwide. Inflammation-mediated cancer accounts for ~15% of all malignancies, strongly necessitating investigation of the molecular interactions at play. Inflammatory reactive oxygen and ...

Mutamba, James T. (James Tendai)

2011-01-01T23:59:59.000Z

145

Quantification of the 2-Deoxyribonolactone and Nucleoside 5 '-Aldehyde Products of 2-Deoxyribose Oxidation in DNA and Cells by Isotope-Dilution Gas Chromatography Mass Spectrometry: Differential Effects of gamma-Radiation and Fe[superscript 2+]-EDTA  

E-Print Network [OSTI]

The oxidation of 2-deoxyribose in DNA has emerged as a critical determinant of the cellular toxicity of oxidative damage to DNA, with oxidation of each carbon producing a unique spectrum of electrophilic products. We have ...

Chan, Wan Simon

146

BDS thin film damage competition  

SciTech Connect (OSTI)

A laser damage competition was held at the 2008 Boulder Damage Symposium in order to determine the current status of thin film laser resistance within the private, academic, and government sectors. This damage competition allows a direct comparison of the current state-of-the-art of high laser resistance coatings since they are all tested using the same damage test setup and the same protocol. A normal incidence high reflector multilayer coating was selected at a wavelength of 1064 nm. The substrates were provided by the submitters. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials, and layer count will also be shared.

Stolz, C J; Thomas, M D; Griffin, A J

2008-10-24T23:59:59.000Z

147

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

SciTech Connect (OSTI)

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

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

2010-06-29T23:59:59.000Z

148

Prediction of Damage in Randomly Oriented Short-Fibre Composites by means of A Mechanistic Approach  

SciTech Connect (OSTI)

A micro-macro mechanistic approach to damage in short-fiber composites is developed in this paper. At the micro-scale, the damage mechanisms such as matrix cracking, fiber/matrix debonding are analyzed to define the associated damage variables. The stiffness reduction law dependent on these variables is then established using micromechanical models and average orientation distributions of fibers and microcracks. The macroscopic response is obtained by means of thermodynamics of continuous media, continuum damage mechanics and a finite element formulation.

Nguyen, Ba Nghiep; Khaleel, Mohammad A.

2004-05-01T23:59:59.000Z

149

Prediction of Damage in Randomly Oriented Short-Fibre Composites by means of A Mechanistic Approach  

SciTech Connect (OSTI)

A micro-macro mechanistic approach to damage in short-fiber composites is developed in this paper. At the micro-scale, the damage mechanisms such as matrix cracking, fiber/matrix debonding are analyzed to define the associated damage variables. The stiffness reduction law dependent on these variables is then established using micromechanical models and average orientation distributions of fibers and microcracks. The macroscopic response is obtained by means of thermodynamics of continuous media, continuum damage mechanics and a finite element formulation.

Nguyen, Ba NGHIEP; Khaleel, Mohammad A.

2004-03-01T23:59:59.000Z

150

Laser induced damage of fused silica polished optics due to a droplet forming organic contaminant  

SciTech Connect (OSTI)

We report on the effect of organic molecular contamination on single shot laser induced damage density at the wavelength of 351 nm, with a 3 ns pulse length. Specific contamination experiments were made with dioctylphthalate (DOP) in liquid or gaseous phase, on the surface of fused silica polished samples, bare or solgel coated. Systematic laser induced damage was observed only in the case of liquid phase contamination. Different chemical and morphological characterization methods were used to identify and understand the damage process. We demonstrate that the contaminant morphology, rather than its physicochemical nature, can be responsible for the decrease of laser induced damage threshold of optics.

Bien-Aime, Karell; Neauport, Jerome; Tovena-Pecault, Isabelle; Fargin, Evelyne; Labrugere, Christine; Belin, Colette; Couzi, Michel

2009-04-20T23:59:59.000Z

151

Electrochemical Characterization of Escherichia coli Adaptive Response Protein AidB  

E-Print Network [OSTI]

When exposed to known DNA-damaging alkylating agents, Escherichia coli cells increase production of four DNA repair enzymes: Ada, AlkA, AlkB, and AidB. The role of three enzymes (Ada, AlkA, and AlkB) in repairing DNA lesions ...

Hamill, Michael J.

152

The Application of Flow Cytometry to Examine Damage Clearance in Stem Cells From Whole-Body Irradiated Mice  

SciTech Connect (OSTI)

The bone marrow contains many types of cells. Approximately 1-2% of these cells are critical for life, these are the so-called ‘bone marrow stem cells’ which divide indefinitely to produce platelets, red blood cells and white blood cells. Death of the bone marrow stem cells results in a diminished ability of the organism to make new blood cell components and can be fatal without medical intervention, such as a bone marrow transplant. Bone marrow stem cells are considered to be particularly sensitive to radiation injury. Therefore, it is important to understand how these cells response to total body radiation exposure and how these cells can be protected from radiation damage. The aim of this project was to determine if these critical cells in the bone marrow are susceptible to short-term and long-term injury after a whole-body exposure to a sub-lethal low dose of ionizing radiation. The overall aims were to determine if the extent of injury produced by the sub-lethal radiation exposure would be cleared from the stem cells and therefore present no long- term genetic risk to the organism, or if the radiation injury persisted and had an adverse long-term consequences for the cell genome. This research question is of interest in order to define the risks to exposed persons after occupational, accidental or terrorism-related sub-lethal low-dose radiation exposures. The novel aspect of this project was the methodology used to obtain the bone marrow stem cell-like cells and examining the outcomes of sub-lethal low-dose radiation in a mammalian animal model. Four radiation treatments were used: single treatments of 0.01Gy, 0.1 Gy, 1 Gy and ten treatments of 0.1 Gy given over 10 days. Bone marrow stem cell-like cells were then harvested 6 hours, 24 hours and 24 days later. The levels of radiation-induced cell death, damage to DNA and permanent changes to cellular DNA were measured in the isolated stem cell-like cells after each radiation treatment and time point and then the results were compared. As expected, the largest radiation dose produced the greatest level of damage but a linear relationship did not exist between cellular effects and radiation dose. The low dose exposures appeared to be more efficient at producing damage than the highest dose when normalized for the initial extent of damage. Additionally, immune stimulation given prior to radiation exposure appeared to protect the critical bone marrow stem cell population from radiation injury. The data suggest that the response of bone marrow stem-cell like cells to radiation injury is dependent on the extent of the initial levels of damage and the effects of total-body low-dose exposures can not be predicted by extrapolating from high dose exposures. This research has provided new information about the radiation sensitivity of bone marrow stem cell-like cells following total-body exposures, and suggests that these critical cells might be more sensitive to radiation than more mature cells in the bone marrow. Further work is need with intermediate radiation doses to confirm this conclusion.

Marples, Brian; Kovalchuk, Olga; McGonagle, Michele; Martinez, Alvaro; Wilson, George, D.

2010-02-26T23:59:59.000Z

153

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

SciTech Connect (OSTI)

It has been long recognized that a significant fraction of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying enzymes may be even more prominent in the case of low-dose, low-LET irradiation, as the majority of genetic damage may be caused by secondary oxidative species. In this study we have attempted to decipher the roles of the superoxide dismutase (SOD) genes, which are responsible for detoxifying the superoxide anions. We used adenovirus vectors to deliver RNA interference (RNAi or siRNA) technology to down-regulate the expression levels of the SOD genes. We have also over-expressed the SOD genes by use of recombinant adenovirus vectors. Cells infected with the vectors were then subjected to low dose ?-irradiation. Total RNA were extracted from the exposed cells and the expression of 9000 genes were profiled by use of cDNA microarrays. The result showed that low dose radiation had clear effects on gene expression in HCT116 cells. Both over-expression and down-regulation of the SOD1 gene can change the expression profiles of sub-groups of genes. Close to 200 of the 9000 genes examined showed over two-fold difference in expression under various conditions. Genes with changed expression pattern belong to many categories that include: early growth response, DNA-repair, ion transport, apoptosis, and cytokine response.

Eric Y. Chuang

2006-08-31T23:59:59.000Z

154

Application of Nonlinear Elastic Resonance Spectroscopy For Damage Detection In Concrete: An Interesting Story  

SciTech Connect (OSTI)

Nonlinear resonance ultrasound spectroscopy experiments conducted on concrete cores, one chemically and mechanically damaged by alkali-silica reactivity, and one undamaged, show that this material displays highly nonlinear wave behavior, similar to many other damaged materials. They find that the damaged sample responds more nonlinearly, manifested by a larger resonant peak and modulus shift as a function of strain amplitude. The nonlinear response indicates that there is a hysteretic influence in the stress-strain equation of state. Further, as in some other materials, slow dynamics are present. The nonlinear response they observe in concrete is an extremely sensitive indicator of damage. Ultimately, nonlinear wave methods applied to concrete may be used to guide mixing, curing, or other production techniques, in order to develop materials with particular desired qualities such as enhanced strength or chemical resistance, and to be used for damage inspection.

Byers, Loren W. [Los Alamos National Laboratory; Ten Cate, James A. [Los Alamos National Laboratory; Johnson, Paul A. [Los Alamos National Laboratory

2012-06-28T23:59:59.000Z

155

Unexpected irreversible damage of an asymmetric bismuth silicate photorefractive spatial light modulator  

SciTech Connect (OSTI)

Unexpected irreversible damage occurred repeatedly in the asymmetric bismuth silicate (BSO)photorefractive spatial light modulator under some operation modes, even though thepower of the write-light beam does not exceed the optical damage threshold. Accordingto the microscopic surface images and the Raman spectra of the BSO film, suddenrising of temperature in local areas caused by the drift of the photon-induced electronsis responsible for the damage; the damage exists not only on the surface but also insidethe BSO crystal. The damage is relative to the structure of the spatial lightmodulator, the operation mode, and the growth of the BSO crystal. The informationprovided by the damage is useful for optimizing the structure, the operation modes, and the performance of the photorefractive spatial light modulators.

Li Xiujian; Yang Jiankun; Yang Juncai; Chang Shengli; Liu Ju; Hu Wenhua

2007-06-20T23:59:59.000Z

156

Damage detection in initially nonlinear systems  

SciTech Connect (OSTI)

The primary goal of Structural Health Monitoring (SHM) is to detect structural anomalies before they reach a critical level. Because of the potential life-safety and economic benefits, SHM has been widely studied over the past decade. In recent years there has been an effort to provide solid mathematical and physical underpinnings for these methods; however, most focus on systems that behave linearly in their undamaged state - a condition that often does not hold in complex 'real world' systems and systems for which monitoring begins mid-lifecycle. In this work, we highlight the inadequacy of linear-based methodology in handling initially nonlinear systems. We then show how the recently developed autoregressive support vector machine (AR-SVM) approach to time series modeling can be used for detecting damage in a system that exhibits initially nonlinear response. This process is applied to data acquired from a structure with induced nonlinearity tested in a laboratory environment.

Bornn, Luke [Los Alamos National Laboratory; Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

157

Remote sensing and forest damage  

SciTech Connect (OSTI)

Each year, damage to North American forests caused by insects, diseases, pollution, and fire results in multibillion dollar losses of revenue and resources. To respond to these losses effectively, forest managers need timely information on the location, extent, and spread of the damage. Traditional techniques for monitoring forest damage include high-resolution aerial photography, color infrared photography, and visual reconnaissance mapping. These techniques require visual interpretation of the data and often are somewhat subjective. In addition, because such analyses are time-consuming and costly, many areas of forest are never mapped, and in cases where maps exist, they often are obsolete or incomplete. An airborne imager has been developed to solve the problems of time-consuming visual analysis and interpretations. The Programmable Multispectral Imager measures small changes - invisible by conventional detection methods - in light reflected by the forest canopy. The PMI measures the color an intensity of reflected light and records this information digitally in computer tape aboard an aircraft. This information is then available for later entry into a computer for processing and enhancement. Although airborne imagers have been available for nearly three decades, they have not been used extensively for forest damage assessment or other forestry applications because of their poor sensitivity and their limited number of fixed spectral channels. The PMI is the first of a new generation of imagers that combine high sensitivity with the flexibility of continuous spectral coverage. This allows scientists to evaluate the potential causes and effects of stress on vegetation.

Reid, N.J.

1987-05-01T23:59:59.000Z

158

DNA Sequencing apparatus  

DOE Patents [OSTI]

An automated DNA sequencing apparatus having a reactor for providing at least two series of DNA products formed from a single primer and a DNA strand, each DNA product of a series differing in molecular weight and having a chain terminating agent at one end; separating means for separating the DNA products to form a series bands, the intensity of substantially all nearby bands in a different series being different, band reading means for determining the position an This invention was made with government support including a grant from the U.S. Public Health Service, contract number AI-06045. The U.S. government has certain rights in the invention.

Tabor, Stanley (Cambridge, MA); Richardson, Charles C. (Chestnut Hill, MA)

1992-01-01T23:59:59.000Z

159

Method for producing damage resistant optics  

DOE Patents [OSTI]

The present invention provides a system that mitigates the growth of surface damage in an optic. Damage to the optic is minimally initiated. In an embodiment of the invention, damage sites in the optic are initiated, located, and then treated to stop the growth of the damage sites. The step of initiating damage sites in the optic includes a scan of the optic using a laser to initiate defects. The exact positions of the initiated sites are identified. A mitigation process is performed that locally or globally removes the cause of subsequent growth of the damaged sites.

Hackel, Lloyd A. (Livermore, CA); Burnham, Alan K. (Livermore, CA); Penetrante, Bernardino M. (San Ramon, CA); Brusasco, Raymond M. (Livermore, CA); Wegner, Paul J. (Livermore, CA); Hrubesh, Lawrence W. (Pleasanton, CA); Kozlowski, Mark R. (Windsor, CA); Feit, Michael D. (Livermore, CA)

2003-01-01T23:59:59.000Z

160

Retrieval of DNA using soft-landing after mass analysis by ESI-FTICR for enzymatic manipulation  

SciTech Connect (OSTI)

The DNA modifications that lead to mutations are of direct interest for, e.g. the understanding of DNA damage recognition and repair. The characterization of the modified oligonucleotides and enzymatic responses to specific DNA modifications are of primary concern, but also present major analytical challenges. Among the available techniques, mass spectrometry has become an increasingly important tool for the study of oligonucleotides, their mutations, and interactions. Conventionally, mass spectrometry provides mass and structural information (e.g. from dissociation experiments and the use of tandem mass spectrometry). However, the small quantities of material analyzed and the destructive nature of conventional mass spectrometric detection (e.g., due to high energy impact on particle multiplier surfaces) have precluded subsequent use of mass separated biopolymers. The authors report the use of mass spectrometry in conjunction with soft-landing for the high-resolution analysis, separation, and selective collection of oligonucleotides, and their subsequent retrieval for enzymatic manipulation. Fourier transform ion cyclotron resonance mass spectrometry coupled with electrospray ionization (ESI-FTICR) allows nondestructive (i.e., image current) measurement of the mass-to-charge ratios (m/z) of ions with high sensitivity, resolution, and mass accuracy.

Feng, B.; Wunschel, D.S.; Masselon, C.D.; Pasa-Tolic, L.; Smith, R.D.

1999-09-29T23:59:59.000Z

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


161

A damage model for fracking  

E-Print Network [OSTI]

Injections of large volumes of water into tight shale reservoirs allows the extraction of oil and gas not previously accessible. This large volume "super" fracking induces damage that allows the oil and/or gas to flow to an extraction well. The purpose of this paper is to provide a model for understanding super fracking. We assume that water is injected from a small spherical cavity into a homogeneous elastic medium. The high pressure of the injected water generates hoop stresses that reactivate natural fractures in the tight shales. These fractures migrate outward as water is added creating a spherical shell of damaged rock. The porosity associated with these fractures is equal to the water volume injected. We obtain an analytic expression for this volume. We apply our model to a typical tight shale reservoir and show that the predicted water volumes are in good agreement with the volumes used in super fracking.

Norris, J Quinn; Rundle, John B

2015-01-01T23:59:59.000Z

162

2010 MICROBIAL STRESS RESPONSE GORDON RESEARCH CONFERENCE, JULY 18-23, 2010  

SciTech Connect (OSTI)

The 2010 Gordon Research Conference on Microbial Stress Responses provides an open and exciting forum for the exchange of scientific discoveries on the remarkable mechanisms used by microbes to survive in nearly every niche on the planet. Understanding these stress responses is critical for our ability to control microbial survival, whether in the context of biotechnology, ecology, or pathogenesis. From its inception in 1994, this conference has traditionally employed a very broad definition of stress in microbial systems. Sessions will cover the major steps of stress responses from signal sensing to transcriptional regulation to the effectors that mediate responses. A wide range of stresses will be represented. Some examples include (but are not limited to) oxidative stress, protein quality control, antibiotic-induced stress and survival, envelope stress, DNA damage, and nutritional stress. The 2010 meeting will also focus on the role of stress responses in microbial communities, applied and environmental microbiology, and microbial development. This conference brings together researchers from both the biological and physical sciences investigating stress responses in medically- and environmentally relevant microbes, as well as model organisms, using cutting-edge techniques. Computational, systems-level, and biophysical approaches to exploring stress responsive circuits will be integrated throughout the sessions alongside the more traditional molecular, physiological, and genetic approaches. The broad range of excellent speakers and topics, together with the intimate and pleasant setting at Mount Holyoke College, provide a fertile ground for the exchange of new ideas and approaches.

Sarah Ades

2011-07-23T23:59:59.000Z

163

A transfection assay for the biological activity of irradiated PM2 DNA  

E-Print Network [OSTI]

Transfection and Gel Electrophores1s Data for Form I PN2 DNA Exposed to X-Ray Radiation . Transfection and Gel Electrophoresis Data for Form I PN2 DNA Exposed to Ultraviolet Radiation Neasur1ng the Effect of moi of X-Ray Irradiated ONA... of Texas at Dallas Chairman of Advisory Committee: Dr. R. D. Neff A transfection assay was developed to detect radiation-damaged PM2 DNA. By varying growth and incubation condit1ons, the calcium heat shock technique was optimized for PM2 DNA and its...

Newman, Andrew Drennan

1982-01-01T23:59:59.000Z

164

Laser-Induced Damage in DKDP Crystals under Simultaneous Exposure to Laser Harmonics  

SciTech Connect (OSTI)

While KDP and DKDP crystals remain the only viable solution for frequency conversion in large aperture laser systems in the foreseeable future, our understanding of damage behavior in the presence of multiple colors is very limited. Such conditions exist during normal operation where, for third harmonic generation, 1{omega}, 2{omega} and 3{omega} components are present with different energy ratios as they propagate inside the crystal. The objective of this work is to shed light into the damage behavior of frequency conversion crystals during operational conditions as well as probe the fundamental mechanisms of damage initiation. We have performed a series of experiments to quantify the damage performance of pristine (unconditioned) DKDP material under simultaneous exposure to 2{omega} and 3{omega} laser pulses from a 3-ns Nd:YAG laser system as a function of the laser influences at each frequency. Results show that simultaneous dual wavelength exposure leads to a much larger damage density as compared to the total damage resulting from separate exposure at each wavelength. Furthermore, under such excitation conditions, the damage performance is directly related to and can be predicted from the damage behavior of the crystal at each wavelength separately while the mechanism and type of defects responsible for damage initiation are shown to be the same at both 2{omega} and 3{omega} excitation.

Negres, R A; DeMange, P; Radousky, H B; Demos, S G

2005-10-28T23:59:59.000Z

165

4698 Biochemistry 1993, 32, 4698-4701 Sequence-Specific Cleavage of DNA via Nucleophilic Attack of Hydrogen  

E-Print Network [OSTI]

4698 Biochemistry 1993, 32, 4698-4701 Sequence-Specific Cleavage of DNA via Nucleophilic Attack by oxidative damage of the DNA backbone but instead is the result of nucleophilic attack by peroxide. A singleSaccharomyces cerevisae, whichactivatesthephosphodiester for attack by thediffusible smallnucleophile. While Flp

Tullius, Thomas D.

166

Focused ion beam damage to MOS integrated circuits  

SciTech Connect (OSTI)

Commercial focused ion beam (FIB) systems are commonly used to image integrated circuits (ICS) after device processing, especially in failure analysis applications. FIB systems are also often employed to repair faults in metal lines for otherwise functioning ICS, and are being evaluated for applications in film deposition and nanofabrication. A problem that is often seen in FIB imaging and repair is that ICS can be damaged during the exposure process. This can result in degraded response or out-right circuit failure. Because FIB processes typically require the surface of an IC to be exposed to an intense beam of 30--50 keV Ga{sup +} ions, both charging and secondary radiation damage are potential concerns. In previous studies, both types of effects have been suggested as possible causes of device degradation, depending on the type of device examined and/or the bias conditions. Understanding the causes of this damage is important for ICS that are imaged or repaired by a FIB between manufacture and operation, since the performance and reliability of a given IC is otherwise at risk in subsequent system application. In this summary, the authors discuss the relative roles of radiation damage and charging effects during FIB imaging. Data from exposures of packaged parts under controlled bias indicate the possibility for secondary radiation damage during FIB exposure. On the other hand, FIB exposure of unbiased wafers (a more common application) typically results in damage caused by high-voltage stress or electrostatic discharge. Implications for FIB exposure and subsequent IC use are discussed.

FLEETWOOD,D.M.; CAMPBELL,ANN N.; HEMBREE,CHARLES E.; TANGYUNYONG,PAIBOON; JESSING,JEFFREY R.; SODEN,JERRY M.

2000-05-10T23:59:59.000Z

167

International Trade and the Internalization of Environmental Damages  

E-Print Network [OSTI]

estimates of environmental damages efficiently and quickly,an overview of environmental damages and internalizationdo little to decrease environmental damage, and may actually

Karp, Larry; Dumas, Christopher F.; Koo, Bonwoo; Sacheti, Sandeep

1995-01-01T23:59:59.000Z

168

Competition between mesoplasticity and damage under HCF Elasticity/damage shakedown concept  

E-Print Network [OSTI]

during all the sample lifetime of the plasticity and damage effects. The plasticity mechanisms induce in the framework of the continuum damage mechanics, according to the identified physical mechanisms during, the damage growth arrest. Keywords High cycle fatigue; Multiaxial loading; Continuum damage mechanics

Boyer, Edmond

169

28-nm laser damage testing of LIF  

SciTech Connect (OSTI)

We have tested several samples of LIF, both single crystal and press forged, for damage resistance to 10-ns 248-nm pulses at 35 pps. The damage thresholds - the highest levels at which no damage could be produced - ranged from 4 to 6 J/cm/sup 2/ although some test sites survived irradiation at approx. 30 J/cm/sup 2/. We observed that bulk damage is the primary failure mechanism in single crystal and press forged samples and that both types exhibit the same resistance to laser damage.

Foltyn, S.R.; Newman, B.E.

1981-01-01T23:59:59.000Z

170

A micro to macro approach to polymer matrix composites damage modeling : final LDRD report.  

SciTech Connect (OSTI)

Capabilities are developed, verified and validated to generate constitutive responses using material and geometric measurements with representative volume elements (RVE). The geometrically accurate RVEs are used for determining elastic properties and damage initiation and propagation analysis. Finite element modeling of the meso-structure over the distribution of characterizing measurements is automated and various boundary conditions are applied. Plain and harness weave composites are investigated. Continuum yarn damage, softening behavior and an elastic-plastic matrix are combined with known materials and geometries in order to estimate the macroscopic response as characterized by a set of orthotropic material parameters. Damage mechanics and coupling effects are investigated and macroscopic material models are demonstrated and discussed. Prediction of the elastic, damage, and failure behavior of woven composites will aid in macroscopic constitutive characterization for modeling and optimizing advanced composite systems.

English, Shawn Allen; Brown, Arthur A.; Briggs, Timothy M.

2013-12-01T23:59:59.000Z

171

Detection and Repair of Ionizing Radiation-Induced DNA Double Strand Breaks: New Developments in Nonhomologous End Joining  

SciTech Connect (OSTI)

DNA damage can occur as a result of endogenous metabolic reactions and replication stress or from exogenous sources such as radiation therapy and chemotherapy. DNA double strand breaks are the most cytotoxic form of DNA damage, and defects in their repair can result in genome instability, a hallmark of cancer. The major pathway for the repair of ionizing radiation-induced DSBs in human cells is nonhomologous end joining. Here we review recent advances on the mechanism of nonhomologous end joining, as well as new findings on its component proteins and regulation.

Wang, Chen [Departments of Biochemistry and Molecular Biology and Oncology, and Southern Alberta Cancer Research Institute, University of Calgary, Calgary (Canada)] [Departments of Biochemistry and Molecular Biology and Oncology, and Southern Alberta Cancer Research Institute, University of Calgary, Calgary (Canada); Lees-Miller, Susan P., E-mail: leesmill@ucalgary.ca [Departments of Biochemistry and Molecular Biology and Oncology, and Southern Alberta Cancer Research Institute, University of Calgary, Calgary (Canada)

2013-07-01T23:59:59.000Z

172

The Role of Nucleotide Excision Repair in Restoring Replication Following UV-Induced Damage in Escherichia coli  

E-Print Network [OSTI]

The Role of Nucleotide Excision Repair in Restoring Replication Following UV-Induced Damage DNA synthesis in the absence of nucleotide excision repair does not promote cell survivalA mutants....................... 26 Following low doses of UV irradiation cells lacking nucleotide excision

Courcelle, Justin

173

Cell damage seen from Chernobyl  

SciTech Connect (OSTI)

The 30 kilometer radius forbidden zone around the Chernobyl atomic plant serves as a sobering reminder of the world's worst nuclear accident. But for former Soviet biologists, it's also a unique natural laboratory. And one scientist, Nadejda Gulaya of Kiev's Pallaguine Institute of Biochemistry, has been doing studies that she claims offer surprising evidence of Chernobyl's after-effects. Prolonged exposure to radioactive fallout from the 1986 accident, she says, has caused damage to cell membranes in both animals and humans. For the past year, Gulaya has been comparing tissues from animals such as mink, pigs, and rodents inhabiting the Chernobyl area with those from other parts of Ukraine. Her conclusion: Exposure to radiation has, in many cases, caused alterations to membrane phospholipids. These changes, are similar to those that disrupt cellular metabolism following exposure to oxidizing free radicals. Gulaya also has preliminary data from human studies. She claims to have found similar alterations in the neurons of people who have died since being exposed to Chernobyl radiation. That leads her to speculate that the frequent psychiatric disorders may not just be from mental stress or radiophobia, but might reflect actual damage to the central nervous system.

Not Available

1992-07-24T23:59:59.000Z

174

ANALYTICAL NEUTRONIC STUDIES CORRELATING FAST NEUTRON FLUENCE TO MATERIAL DAMAGE IN CARBON, SILICON, AND SILICON CARBIDE  

SciTech Connect (OSTI)

This study evaluates how fast neutron fluence >0.1 MeV correlates to material damage (i.e., the total fluence spectrum folded with the respective material’s displacements-per- atom [dpa] damage response function) for the specific material fluence spectra encountered in Next Generation Nuclear Plant (NGNP) service and the irradiation tests conducted in material test reactors (MTRs) for the fuel materials addressed in the white paper. It also reports how the evaluated correlations of >0.1 MeV fluence to material damage vary between the different spectral conditions encountered in material service versus testing.

Jim Sterbentz

2011-06-01T23:59:59.000Z

175

Simulated Fatigue Damage Index on Mooring Lines of a Gulf of Mexico Truss Spar Determined from Recorded Field Data  

E-Print Network [OSTI]

. The platform is equipped with an Environmental Platform Response Monitoring System (EPRMS) which records real-time motions, environmental parameters and loads. These measurements were used to hind-cast the platform mooring tensions and estimate fatigue damage...

Kiecke, Adam Fuller

2012-07-16T23:59:59.000Z

176

Alpha decay self-damage in cubic and monoclinic zirconolite  

SciTech Connect (OSTI)

Samples of primarily-monoclinic /sup 238/Pu-doped zirconolite were stored at ambient temperature to allow accumulation of alpha decay self-damage to a dose of 1 x 10/sup 24/ ..cap alpha../m/sup 3/ (equivalent to a SYNROC age of approx. 10/sup 3/y). Bulk swelling reached 2.3 vol% with no tendency toward saturation, a damage response similar to that observed for cubic Pu-doped zirconolite. X-ray volumetric swelling at 4 x 10/sup 24/ ..cap alpha../m/sup 3/ was 1 vol%, considerably less than that for the cubic material. Changes in cell dimensions differed significantly from those reported by others for a monoclinic natural mineral. Extensive microcracking was observed, and is attributed at least partially to swelling differences between the matrix and minor phases.

Clinard, F.W. Jr.; Land, C.C.; Peterson, D.E.; Rohr, D.L.; Roof, R.B.

1981-01-01T23:59:59.000Z

177

Structural damage identification in wind turbine blades using piezoelectric active sensing with ultrasonic validation  

SciTech Connect (OSTI)

This paper gives a brief overview of a new project at LANL in structural damage identification for wind turbines. This project makes use of modeling capabilities and sensing technology to understand realistic blade loading on large turbine blades, with the goal of developing the technology needed to automatically detect early damage. Several structural health monitoring (SHM) techniques using piezoelectric active materials are being investigated for the development of wireless, low power sensors that interrogate sections of the wind turbine blade using Lamb wave propagation data, frequency response functions (FRFs), and time-series analysis methods. The modeling and sensor research will be compared with extensive experimental testing, including wind tunnel experiments, load and fatigue tests, and ultrasonic scans - on small- to mid-scale turbine blades. Furthermore, this study will investigate the effect of local damage on the global response of the blade by monitoring low-frequency response changes.

Claytor, Thomas N [Los Alamos National Laboratory; Ammerman, Curtt N [Los Alamos National Laboratory; Park, Gyu Hae [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Farrar, Charles R [Los Alamos National Laboratory; Atterbury, Marie K [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

178

Supramolecular DNA nanotechnology : discrete nanoparticle organization, three-dimensional DNA construction, and molecule templated DNA assembly.  

E-Print Network [OSTI]

??The field of structural DNA nanotechnology utilizes DNA's powerful base-pairing molecular recognition criteria to help solve real challenges facing researchers in material science and nanotechnology,… (more)

Aldaye, Faisal A., 1979-

2008-01-01T23:59:59.000Z

179

Insulator damage endangers public, power reliability; ratepayers...  

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

Insulator-damage-endangers-public-power-reliability-ratepayers-foot-repair-bill Sign In About | Careers | Contact | Investors | bpa.gov Search News & Us Expand News & Us...

180

Differences in Electrostatic Potential Around DNA Fragments Containing Guanine and 8-oxo-Guanine  

SciTech Connect (OSTI)

hanges of electrostatic potential (EP) around the DNA molecule resulting from chemical modifications of nucleotides may play a role in enzymatic recognition of damaged sites. Effects of chemical modifications of nucleotides on the structure of DNA have been characterized through large scale density functional theory computations. Quantum mechanical structural optimizations of DNA fragments with three pairs of nucleotoides and accompanying counteractions were performed with a B3LYP exchange-correlation functional and 6-31G** basis sets. The “intact” DNA fragment contained guanine in the middle layer, while the “damaged” fragment had the guanine replaced with 8-oxo-guanine. The electrostatic potential around these DNA fragments was projected on a surface around the double helix. The 2D maps of EP of intact and damaged DNA fragments were analyzed to identify these modifications of EP that result from the occurrence of 8-oxo-guanine. It was found that distortions of the phosphate groups and displacements of the accompanying countercations are clearly reflected in the EP maps.

Haranczyk, Maciej; Gutowski, Maciej S.

2007-02-01T23:59:59.000Z

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


181

Patterning nanocrystals using DNA  

SciTech Connect (OSTI)

One of the goals of nanotechnology is to enable programmed self-assembly of patterns made of various materials with nanometer-sized control. This dissertation describes the results of experiments templating arrangements of gold and semiconductor nanocrystals using 2'-deoxyribonucleic acid (DNA). Previously, simple DNA-templated linear arrangements of two and three nanocrystals structures have been made.[1] Here, we have sought to assemble larger and more complex nanostructures. Gold-DNA conjugates with 50 to 100 bases self-assembled into planned arrangements using strands of DNA containing complementary base sequences. We used two methods to increase the complexity of the arrangements: using branched synthetic doublers within the DNA covalent backbone to create discrete nanocrystal groupings, and incorporating the nanocrystals into a previously developed DNA lattice structure [2][3] that self-assembles from tiles made of DNA double-crossover molecules to create ordered nanoparticle arrays. In the first project, the introduction of a covalently-branched synthetic doubler reagent into the backbone of DNA strands created a branched DNA ''trimer.'' This DNA trimer templated various structures that contained groupings of three and four gold nanoparticles, giving promising, but inconclusive transmission electron microscopy (TEM) results. Due to the presence of a variety of possible structures in the reaction mixtures, and due to the difficulty of isolating the desired structures, the TEM and gel electrophoresis results for larger structures having four particles, and for structures containing both 5 and 10 nm gold nanoparticles were inconclusive. Better results may come from using optical detection methods, or from improved sample preparation. In the second project, we worked toward making two-dimensional ordered arrays of nanocrystals. We replicated and improved upon previous results for making DNA lattices, increasing the size of the lattices to a length greater than 20 {micro}m, and collecting atomic force microscopy (AFM) images up to 30 {micro}m. We found the lattices' requirement of divalent magnesium cations to stabilize Holliday junctions to be incompatible with the stability of charge-stabilized gold nanoparticles used for the experiments here, and gold particles added indiscriminately to the lattice surface through non-specific binding. Redesigning the lattices to avoid magnesium may improve results.

Williams, Shara Carol

2003-09-01T23:59:59.000Z

182

Visualizing the Local Optical Response of Semiconducting Carbon Nanotubes to  

E-Print Network [OSTI]

Visualizing the Local Optical Response of Semiconducting Carbon Nanotubes to DNA-Wrapping Huihong ABSTRACT We studied the local optical response of semiconducting single-walled carbon nanotubes to wrapping-field images of single nanotubes reveal large DNA-wrapping-induced red shifts of the exciton energy

Novotny, Lukas

183

Final Report [The c-Abl signaling network in the radioadaptive response  

SciTech Connect (OSTI)

The radioadaptive response, or radiation hormesis, i.e. a low dose of radiation can protect cells and organisms from the effects of a subsequent higher dose, is a widely recognized phenomenon. Mechanisms underlying such radiation hormesis, however, remain largely unclear. Preliminary studies indicate an important role of c-Abl signaling in mediating the radioadaptive response. We propose to investigate how c-Abl regulates the crosstalk between p53 and NF?B in response to low doses irradiation. We found in our recent study that low dose IR induces a reciprocal p53 suppression and NF?B activation, which induces HIF-a and subsequently a metabolic reprogramming resulting in a transition from oxidative phosphorylation to glycolysis. Of importance is that this glycolytic switch is essential for the radioadaptive response. This low-dose radiationinduced HIF1? activation was in sharp contrast with the high-dose IR-induced p53 activation and HIF1? inhibition. HIF1? and p53 seem to play distinct roles in mediating the radiation dose-dependent metabolic response. The induction of HIF1?-mediated glycolysis is restricted to a low dose range of radiation, which may have important implications in assessing the level of radiation exposure and its potential health risk. Our results support a dose-dependent metabolic response to IR. When IR doses are below the threshold of causing detectable DNA damage (<0.2Gy) and thus little p53 activation, HIF1? is induced resulting in induction of glycolysis and increased radiation resistance. When the radiation dose reaches levels eliciting DNA damage, p53 is activated and diminishes the activity of HIF1? and glycolysis, leading to the induction of cell death. Our work challenges the LNT model of radiation exposure risk and provides a metabolic mechanism of radioadaptive response. The study supports a need for determining the p53 and HIF1? activity as a potential reliable biological readout of radiation exposure in humans. The exquisite sensitivity of cellular metabolism to low doses of radiation could also serve as a valuable biomarker for estimating the health effects of low-level radiation exposure.

Chi-Min, Yuan

2014-01-28T23:59:59.000Z

184

Integrating natural resource damage assessment and environmental restoration activities at DOE facilities  

SciTech Connect (OSTI)

Environmental restoration activities are currently under way at many U.S. Department of Energy (DOE) sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended. DOE is the CERCLA lead response agency for these activities. Section 120 of CERCLA also could subject DOE to liability for natural resource damages resulting from hazardous substance releases at its sites. A Natural Resource Damage Assessment (NRDA) process is used to determine whether natural resources have been injured and to calculate compensatory monetary damages to be used to restore the natural resources. In addition to restoration costs, damages may include costs of conducting the damage assessment and compensation for interim losses of natural resource services that occur before resource restoration is complete. Natural resource damages represent a potentially significant source of additional monetary claims under CERCLA, but are not well known or understood by many DOE staff and contractors involved in environmental restoration activities. This report describes the requirements and procedures of NRDA in order to make DOE managers aware of what the process is designed to do. It also explains how to integrate the NRDA and CERCLA Remedial Investigation/Feasibility Study processes, showing how the technical and cost analysis concepts of NRDA can be borrowed at strategic points in the CERCLA process to improve decisionmaking and more quickly restore natural resource services at the lowest total cost to the public.

NONE

1993-10-01T23:59:59.000Z

185

Integrating Natural Resource Damage Assessment and environmental restoration activities at DOE facilities  

SciTech Connect (OSTI)

Environmental restoration activities are currently under way at many US Department of Energy (DOE) sites under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). DOE is the CERCLA lead response agency for these activities. Section 120 of CERCLA also could subject DOE to liability for natural resource damages resulting from hazardous substance releases at its sites. A Natural Resource Damage Assessment (NRDA) process is used to determine whether natural resources have been injured and to calculate compensatory monetary damages to be used to restore the natural resources. In addition to restoration costs, damages may include costs of conducting the damage assessment and compensation for interim losses of natural resource services that occur before resource restoration is complete. Natural resource damages represent a potentially significant source of additional monetary claims under CERCLA, but are not well known or understood by many DOE staff and contractors involved in environmental restoration activities. This report describes the requirements and procedures of NRDA in order to make DOE managers aware of what the process is designed to do. It also explains how to integrate the NRDA and CERCLA Remedial Investigation/Feasibility Study processes, showing how the technical and cost analysis concepts of NRDA can be borrowed at strategic points in the CERCLA process to improve decisionmaking and more quickly restore natural resource services at the lowest total cost to the public.

Not Available

1993-10-01T23:59:59.000Z

186

Structure of an aprataxin?DNA complex with insights into AOA1 neurodegenerative disease  

SciTech Connect (OSTI)

DNA ligases finalize DNA replication and repair through DNA nick-sealing reactions that can abort to generate cytotoxic 5'-adenylation DNA damage. Aprataxin (Aptx) catalyzes direct reversal of 5'-adenylate adducts to protect genome integrity. Here the structure of a Schizosaccharomyces pombe Aptx-DNA-AMP-Zn{sup 2+} complex reveals active site and DNA interaction clefts formed by fusing a histidine triad (HIT) nucleotide hydrolase with a DNA minor groove-binding C{sub 2}HE zinc finger (Znf). An Aptx helical 'wedge' interrogates the base stack for sensing DNA ends or DNA nicks. The HIT-Znf, the wedge and an '[F/Y]PK' pivot motif cooperate to distort terminal DNA base-pairing and direct 5'-adenylate into the active site pocket. Structural and mutational data support a wedge-pivot-cut HIT-Znf catalytic mechanism for 5'-adenylate adduct recognition and removal and suggest that mutations affecting protein folding, the active site pocket and the pivot motif underlie Aptx dysfunction in the neurodegenerative disorder ataxia with oculomotor apraxia 1 (AOA1).

Tumbale, Percy; Appel, C. Denise; Kraehenbuehl, Rolf; Robertson, Patrick D.; Williams, Jessica S.; Krahn, Joe; Ahel, Ivan; Williams, R. Scott (NIEHS); (Manchester)

2012-09-17T23:59:59.000Z

187

A new damage testing system for detailed evaluation of damage behavior of bulk KDP and DKDP  

SciTech Connect (OSTI)

We describe a new damage testing approach and instrumentation that provides quantitative measurements of bulk damage performance versus fluence for several frequencies. A major advantage of this method is that it can simultaneously provide direct information on pinpoint density and size, and beam obscuration. This allows for more accurate evaluation of material performance under operational conditions. Protocols for laser conditioning to improve damage performance can also be easily and rapidly evaluated.This damage testing approach has enabled us to perform complex experiments toward probing the fundamental mechanisms of damage initiation and conditioning.

DeMange, P; Negres, R A; Carr, C W; Radousky, H B; Demos, S G

2004-11-17T23:59:59.000Z

188

DNA Repair Alterations in Children With Pediatric Malignancies: Novel Opportunities to Identify Patients at Risk for High-Grade Toxicities  

SciTech Connect (OSTI)

Purpose: To evaluate, in a pilot study, the phosphorylated H2AX ({gamma}H2AX) foci approach for identifying patients with double-strand break (DSB) repair deficiencies, who may overreact to DNA-damaging cancer therapy. Methods and Materials: The DSB repair capacity of children with solid cancers was analyzed compared with that of age-matched control children and correlated with treatment-related normal-tissue responses (n = 47). Double-strand break repair was investigated by counting {gamma}H2AX foci in blood lymphocytes at defined time points after irradiation of blood samples. Results: Whereas all healthy control children exhibited proficient DSB repair, 3 children with tumors revealed clearly impaired DSB repair capacities, and 2 of these repair-deficient children developed life-threatening or even lethal normal-tissue toxicities. The underlying mutations affecting regulatory factors involved in DNA repair pathways were identified. Moreover, significant differences in mean DSB repair capacity were observed between children with tumors and control children, suggesting that childhood cancer is based on genetic alterations affecting DSB repair function. Conclusions: Double-strand break repair alteration in children may predispose to cancer formation and may affect children's susceptibility to normal-tissue toxicities. Phosphorylated H2AX analysis of blood samples allows one to detect DSB repair deficiencies and thus enables identification of children at risk for high-grade toxicities.

Ruebe, Claudia E., E-mail: claudia.ruebe@uks.e [Department of Radiation Oncology, Saarland University, Homburg/Saar (Germany); Fricke, Andreas; Schneider, Ruth; Simon, Karin; Kuehne, Martin; Fleckenstein, Jochen [Department of Radiation Oncology, Saarland University, Homburg/Saar (Germany); Graeber, Stefan [Institute of Medical Biometrics, Epidemiology and Medical Informatics, Saarland University, Homburg/Saar (Germany); Graf, Norbert [Department of Pediatric Hematology and Oncology, Saarland University, Homburg/Saar (Germany); Ruebe, Christian [Department of Radiation Oncology, Saarland University, Homburg/Saar (Germany)

2010-10-01T23:59:59.000Z

189

Coarse-graining DNA for simulations of DNA nanotechnology  

E-Print Network [OSTI]

To simulate long time and length scale processes involving DNA it is necessary to use a coarse-grained description. Here we provide an overview of different approaches to such coarse graining, focussing on those at the nucleotide level that allow the self-assembly processes associated with DNA nanotechnology to be studied. OxDNA, our recently-developed coarse-grained DNA model, is particularly suited to this task, and has opened up this field to systematic study by simulations. We illustrate some of the range of DNA nanotechnology systems to which the model is being applied, as well as the insights it can provide into fundamental biophysical properties of DNA.

Doye, Jonathan P K; Louis, Ard A; Romano, Flavio; Sulc, Petr; Matek, Christian; Snodin, Benedict E K; Rovigatti, Lorenzo; Schreck, John S; Harrison, Ryan M; Smith, William P J

2013-01-01T23:59:59.000Z

190

Pathogenic Mechanisms in Ischemic Damage: A Computational Study  

E-Print Network [OSTI]

Pathogenic Mechanisms in Ischemic Damage: A Computational Study Eytan Ruppin and Elad Ofer Depts of ischemic tissue damage during acute stroke. Two prime pathogenic mechanisms, cor- tical spreading the patterns of damage that arise if damage is caused by either mechanism are generated. These damaged tissue

Ruppin, Eytan

191

Underground infrastructure damage for a Chicago scenario  

SciTech Connect (OSTI)

Estimating effects due to an urban IND (improvised nuclear device) on underground structures and underground utilities is a challenging task. Nuclear effects tests performed at the Nevada Test Site (NTS) during the era of nuclear weapons testing provides much information on how underground military structures respond. Transferring this knowledge to answer questions about the urban civilian environment is needed to help plan responses to IND scenarios. Explosions just above the ground surface can only couple a small fraction of the blast energy into an underground shock. The various forms of nuclear radiation have limited penetration into the ground. While the shock transmitted into the ground carries only a small fraction of the blast energy, peak stresses are generally higher and peak ground displacement is lower than in the air blast. While underground military structures are often designed to resist stresses substantially higher than due to the overlying rocks and soils (overburden), civilian structures such as subways and tunnels would generally only need to resist overburden conditions with a suitable safety factor. Just as we expect the buildings themselves to channel and shield air blast above ground, basements and other underground openings as well as changes of geology will channel and shield the underground shock wave. While a weaker shock is expected in an urban environment, small displacements on very close-by faults, and more likely, soils being displaced past building foundations where utility lines enter could readily damaged or disable these services. Immediately near an explosion, the blast can 'liquefy' a saturated soil creating a quicksand-like condition for a period of time. We extrapolate the nuclear effects experience to a Chicago-based scenario. We consider the TARP (Tunnel and Reservoir Project) and subway system and the underground lifeline (electric, gas, water, etc) system and provide guidance for planning this scenario.

Dey, Thomas N [Los Alamos National Laboratory; Bos, Rabdall J [Los Alamos National Laboratory

2011-01-25T23:59:59.000Z

192

Carbon Fiber Damage in Accelerator Beam  

E-Print Network [OSTI]

Carbon fibers are commonly used as moving targets in Beam Wire Scanners. Because of their thermomechanical properties they are very resistant to particle beams. Their strength deteriorates with time due to radiation damage and low-cycle thermal fatigue. In case of high intensity beams this process can accelerate and in extreme cases the fiber is damaged during a single scan. In this work a model describing the fiber temperature, thermionic emission and sublimation is discussed. Results are compared with fiber damage test performed on SPS beam in November 2008. In conclusions the limits of Wire Scanner operation on high intensity beams are drawn.

Sapinski, M; Guerrero, A; Koopman, J; Métral, E

2009-01-01T23:59:59.000Z

193

War damages and reconstruction of Peruca dam  

SciTech Connect (OSTI)

The paper describes the heavy damages caused by blasting in the Peruca rockfill dam in Croatia in January 1993. Complete collapse of the dam by overtopping was prevented through quick action of the dam owner by dumping clayey gravel on the lowest sections of the dam crest and opening the bottom outlet of the reservoir, thus efficiently lowering the water level. After the damages were sufficiently established and alternatives for restoration of the dam were evaluated, it was decided to construct a diaphragm wall through the damaged core in the central dam part as the impermeable dam element and to rebuild the central clay core at the dam abutments. Reconstruction works are described.

Nonveiller, E. [Univ. of Zagreb (Croatia). Faculty of Civil Engineering] [Univ. of Zagreb (Croatia). Faculty of Civil Engineering; Rupcic, J. [Univ. of Zagreb (Croatia). Faculty of Civil Engineering] [Univ. of Zagreb (Croatia). Faculty of Civil Engineering; [Elektroprojekt Consulting Engineering, Zagreb (Croatia); Sever, Z. [Elektroprojekt Consulting Engineering, Zagreb (Croatia)] [Elektroprojekt Consulting Engineering, Zagreb (Croatia)

1999-04-01T23:59:59.000Z

194

DNA polymerase having modified nucleotide binding site for DNA sequencing  

DOE Patents [OSTI]

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

Tabor, S.; Richardson, C.

1997-03-25T23:59:59.000Z

195

Assessing United States hurricane damage under different environmental conditions  

E-Print Network [OSTI]

Hurricane activity between 1979 and 2011 was studied to determine damage statistics under different environmental conditions. Hurricanes cause billions of dollars of damage every year in the United States, but damage ...

Maheras, Anastasia Francis

2012-01-01T23:59:59.000Z

196

Beam damage of poly(2-chloroethyl methylacrylate) [PCEMA] films...  

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

evaluating x-ray damage. PCEMA has been shown to be more sensitive to degradation than PVC which has also been used as a damage sensitive material useful for comparison of damage...

197

Identifying a transcriptional signature for cell sensitivity to the cancer chemotherapy agent, BCNU  

E-Print Network [OSTI]

Many organisms have evolved DNA damage response mechanisms to deal with the constant damage to DNA caused by endogenous and exogenous agents. These mechanisms activate cell cycle checkpoints to allow time for DNA repair ...

Valiathan, Chandni Rajan

2011-01-01T23:59:59.000Z

198

A poroplastic model for hygro-chemo-mechanical damage of concrete M. Cuomo & A. Nicolosi  

E-Print Network [OSTI]

and to the prediction of long term response of concrete constructions. The crystalline and porous microstruc- tureA poroplastic model for hygro-chemo-mechanical damage of concrete M. Cuomo & A. Nicolosi Department an analytical model for calcium leaching of concrete due to water. The model is set in the framework

Paris-Sud XI, Université de

199

Gurson's plasticity coupled to damage as a CAP model for concrete compaction in dynamics  

E-Print Network [OSTI]

1 Gurson's plasticity coupled to damage as a CAP model for concrete compaction in dynamics Fabrice (compaction) but also the plastic strains in compression and cracking in tension. Recently, new dynamic is generally described by means of the plasticity theory where the spherical and the deviatoric responses

200

Formation damage in underbalanced drilling operations  

E-Print Network [OSTI]

Formation damage has long been recognized as a potential source of reduced productivity and injectivity in both horizontal and vertical wells. From the moment that the pay zone is being drilled until the well is put on production, a formation...

Reyes Serpa, Carlos Alberto

2003-01-01T23:59:59.000Z

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


201

Laser Damage Precursors in Fused Silica  

SciTech Connect (OSTI)

There is a longstanding, and largely unexplained, correlation between the laser damage susceptibility of optical components and both the surface quality of the optics, and the presence of near surface fractures in an optic. In the present work, a combination of acid leaching, acid etching, and confocal time resolved photoluminescence (CTP) microscopy has been used to study laser damage initiation at indentation sites. The combination of localized polishing and variations in indentation loads allows one to isolate and characterize the laser damage susceptibility of densified, plastically flowed and fractured fused silica. The present results suggest that: (1) laser damage initiation and growth are strongly correlated with fracture surfaces, while densified and plastically flowed material is relatively benign, and (2) fracture events result in the formation of an electronically defective rich surface layer which promotes energy transfer from the optical beam to the glass matrix.

Miller, P; Suratwala, T; Bude, J; Laurence, T A; Shen, N; Steele, W A; Feit, M; Menapace, J; Wong, L

2009-11-11T23:59:59.000Z

202

Thin Film Femtosecond Laser Damage Competition  

SciTech Connect (OSTI)

In order to determine the current status of thin film laser resistance within the private, academic, and government sectors, a damage competition was started at the 2008 Boulder Damage Symposium. This damage competition allows a direct comparison of the current state of the art of high laser resistance coatings since they are tested using the same damage test setup and the same protocol. In 2009 a high reflector coating was selected at a wavelength of 786 nm at normal incidence at a pulse length of 180 femtoseconds. A double blind test assured sample and submitter anonymity so only a summary of the results are presented here. In addition to the laser resistance results, details of deposition processes, coating materials and layer count, and spectral results will also be shared.

Stolz, C J; Ristau, D; Turowski, M; Blaschke, H

2009-11-14T23:59:59.000Z

203

Quantitative damage evaluation of localized deep pitting  

SciTech Connect (OSTI)

Localized deep pitting is considered difficult to precisely measure and evaluate using simple techniques and daily-use analysis approaches. A case study was made of carbon steel heat exchangers in a typical fresh cooling water environment that experienced severe pitting. To effectively and precisely evaluate the encountered pitting damage, a simple measurement and analyses approach was devised. In this article, the pitting measurement technique and the damage evaluation approach are presented and discussed in detail.

Al Beed, A.A.; Al Garni, M.A.

2000-04-01T23:59:59.000Z

204

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution...  

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

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Abstract:...

205

Exemplary Hurricane Damage Cleanup Earns Petroleum Reserve Coveted...  

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

Exemplary Hurricane Damage Cleanup Earns Petroleum Reserve Coveted Environmental Award Exemplary Hurricane Damage Cleanup Earns Petroleum Reserve Coveted Environmental Award April...

206

O[superscript 6]-Methylguanine DNA lesions induce an intra-S-phase arrest from which cells exit into apoptosis governed by early and late multi-pathway signaling network activation  

E-Print Network [OSTI]

The O[superscript 6]-methylguanine (O[superscript 6]MeG) DNA lesion is well known for its mutagenic, carcinogenic, and cytotoxic properties, and understanding how a cell processes such damage is of critical importance for ...

Noonan, Ericka M.

207

DNA Structural Nanotechnology Duke University  

E-Print Network [OSTI]

DNA Structural Nanotechnology John Reif Duke University Graduate Students: Harish Chandran&Caltech Tube Lattices #12;Ned Seeman New York University, USA Ned Seeman: Father of DNA Nanotechnology His Initial Ideas & Motivation for DNA Nanotechnology #12;Cube Chen & Seeman, Nature350:631 (1991) Truncated

Reif, John H.

208

Effect of impurities and stress on the damage distributions of rapidly grown KDP crystals  

SciTech Connect (OSTI)

Development of high damage threshold, 50 cm, rapidly grown KF*P frequency triplers for operation of the National Ignition Facility (NIF) in the 14 J/cm2, 351 nm, 3 ns regime requires a thorough understanding of how the crystal growth parameters and technologies affect laser induced damage. Of particular importance is determining the effect of ionic impurities (e.g. Cr3+, Fe3+, Al3+) which may be introduced in widely varying concentrations via starting salts. In addition, organic particulates can contaminate the solution as leachants from growth platforms or via mechanical ablation. Mechanical stresses in the crystals may also play a strong role in the laser-induced damage distribution (LIDD), particularly in the cases of large boules where hydrodynamic forces in the growth tank may be quite high. WE have developed a dedicated, automated damage test system with diagnostic capabilities specifically designed for measured time resolved bulk damage onset and evolution. The data obtained make it possible to construct characteristic damage threshold distributions for each sample. Test results obtained for a variety of KDP samples grown from high purity starting salts and individually doped with Lucite and Teflon, iron, chromium, and aluminium show that the LIDD drops with increasing contamination content. The results also show that solution filtration leads to increased damage performance for undoped crystals but is not solely responsibility for producing the high LIDDs required by the NIF. The highest LIDD measured on a rapidly grown sample indicate that it is possible to produce high damage threshold material using ultrahigh purity, recrystallized starting salts, continuous filtration and a platform designed to minimize internal stress during growth.

Runkel, M.; Tan, M.; De Yoreo, J.; Zaitseva, N.

1997-12-20T23:59:59.000Z

209

Fleet DNA (Presentation)  

SciTech Connect (OSTI)

The Fleet DNA project objectives include capturing and quantifying drive cycle and technology variation for the multitude of medium- and heavy-duty vocations; providing a common data storage warehouse for medium- and heavy-duty vehicle fleet data across DOE activities and laboratories; and integrating existing DOE tools, models, and analyses to provide data-driven decision making capabilities. Fleet DNA advantages include: for Government - providing in-use data for standard drive cycle development, R&D, tech targets, and rule making; for OEMs - real-world usage datasets provide concrete examples of customer use profiles; for fleets - vocational datasets help illustrate how to maximize return on technology investments; for Funding Agencies - ways are revealed to optimize the impact of financial incentive offers; and for researchers -a data source is provided for modeling and simulation.

Walkokwicz, K.; Duran, A.

2014-06-01T23:59:59.000Z

210

Chiral Mesophases of DNA  

E-Print Network [OSTI]

In the hexagonal columnar phase of chiral polymers a bias towards cholesteric twist competes with braiding along an average direction. When the chirality is strong, topological defects proliferate, leading to either a tilt grain boundary phase or a new ``moire state'' with twisted bond order. This moire phase can melt leading to a new phase: the chiral hexatic. I will discuss some recent experimental results from the NIH on DNA liquid crystals in the context of these theories.

Randall D. Kamien

1998-12-08T23:59:59.000Z

211

DNA waves and water  

E-Print Network [OSTI]

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

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

2010-12-23T23:59:59.000Z

212

Fretting Corrosion Damage of Total Hip Prosthesis: Friction Coefficient and Damage Rate Constant Approach  

E-Print Network [OSTI]

1 Fretting Corrosion Damage of Total Hip Prosthesis: Friction Coefficient and Damage Rate Constant Building, University Park 16802 PA USA 4 Chair Professor Center for Research Excellence in Corrosion hip prosthesis. Fretting corrosion tests were conducted with stainless steel and poly (methyl

Boyer, Edmond

213

Subcellular Spatial Correlation of Particle Traversal and Biological Response in Clinical Ion Beams  

SciTech Connect (OSTI)

Purpose: To report on the spatial correlation of physical track information (fluorescent nuclear track detectors, FNTDs) and cellular DNA damage response by using a novel hybrid detector (Cell-Fit-HD). Methods and Materials: The FNTDs were coated with a monolayer of human non-small cell lung carcinoma (A549) cells and irradiated with carbon ions (270.55 MeV u{sup ?1}, rising flank of the Bragg peak). Phosphorylated histone variant H2AX accumulating at the irradiation-induced double-strand break site was labeled (RIF). The position and direction of ion tracks in the FNTD were registered with the location of the RIF sequence as an ion track surrogate in the cell layer. Results: All RIF sequences could be related to their corresponding ion tracks, with mean deviations of 1.09 ?m and ?1.72 ?m in position and of 2.38° in slope. The mean perpendicular between ion track and RIF sequence was 1.58 ?m. The mean spacing of neighboring RIFs exhibited a regular rather than random spacing. Conclusions: Cell-Fit-HD allows for unambiguous spatial correlation studies of cell damage with respect to the intracellular ion traversal under therapeutic beam conditions.

Niklas, Martin, E-mail: m.niklas@dkfz.de [Division of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Abdollahi, Amir [German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion-Beam Therapy Center, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany); Department of Radiation Oncology and Radiation Therapy, University Hospital Heidelberg, Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center, Heidelberg (Germany); Akselrod, Mark S. [Stillwater Crystal Growth Division, Landauer Inc, Stillwater, Oklahoma (United States); Debus, Jürgen [German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Molecular and Translational Radiation Oncology, Heidelberg Ion-Beam Therapy Center, University of Heidelberg Medical School and National Center for Tumor Diseases, German Cancer Research Center, Heidelberg (Germany); Department of Radiation Oncology and Radiation Therapy, University Hospital Heidelberg, Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center, Heidelberg (Germany); Jäkel, Oliver [Division of Medical Physics in Radiation Oncology, German Cancer Research Center, Heidelberg (Germany); German Cancer Consortium, National Center for Radiation Research in Oncology, Heidelberg Institute of Radiation Oncology, Heidelberg (Germany); Department of Radiation Oncology and Radiation Therapy, University Hospital Heidelberg, Heidelberg (Germany); Heidelberg Ion-Beam Therapy Center, Heidelberg (Germany); and others

2013-12-01T23:59:59.000Z

214

Intriguing DNA Editor Has a Structural Trigger  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared LandResponses to EngineeredA GENERAL2RadiativeIntriguing DNA Editor

215

Intriguing DNA Editor Has a Structural Trigger  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFunInfrared LandResponses to EngineeredA GENERAL2RadiativeIntriguing DNA

216

Structural and mechanistic studies of polymerase ? bypass of phenanthriplatin DNA damage  

E-Print Network [OSTI]

Platinum drugs are a mainstay of anticancer chemotherapy. Nevertheless, tumors often display inherent or acquired resistance to platinum-based treatments, prompting the search for new compounds that do not exhibit ...

Gregory, Mark T.

217

E-Print Network 3.0 - alkaloid damages dna Sample Search Results  

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

Antisense-mediated reduction in ADC activity causes minor alterations in the alkaloid profile of cultured hairy roots Summary: Antisense-mediated reduction in ADC activity causes...

218

RhoJ Regulates Melanoma Chemoresistance by Suppressing Pathways that Sense DNA Damage  

E-Print Network [OSTI]

s t-test IPA-3 alone in the same dose. C.purchased from Sigma and IPA-3 was purchased from Tocrispopulation. $watermark-text IPA-3 Cisplatin sensitization

Ho, Hsiang; Aruri, Jayavani; Kapadia, Rubina; Mehr, Hootan; White, Michael A.; Ganesan, Anand K.

2012-01-01T23:59:59.000Z

219

Reactive species and DNA damage in chronic inflammation: Reconciling chemical mechanisms and biological fates  

E-Print Network [OSTI]

Chronic inflammation has long been recognized as a risk factor for many human cancers. One mechanistic link between inflammation and cancer involves the generation of nitric oxide, superoxide and other reactive oxygen and ...

Lonkar, Pallavi

220

A comparison of DNA damage probes in two HMEC lines with X-irradiation  

E-Print Network [OSTI]

L. WISNEWSKI, KATHLEEN A. BJORNSTAD, CHRISTOPHER J. ROSEN,Eleanor Blakely, Kathleen Bjornstad, Polly Chang and Chris

Wisnewski, Christy L.; Bjornstad, Kathleen A.; Rosen, Christoper J.; Chang, Polly Y.; Blakely, Eleanor A.

2008-01-01T23:59:59.000Z

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


221

IN VITRO MUTAGENIC AND DNA AND CHROMOSOMAL DAMAGE ACTIVITY BY SURFACTANT  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:YearRound-UpHeatMulti-Dimensionalthe U.S. Department of EnergyKickoff490 MEMORANDUMDISPERSION OR

222

Evidence of reactive oxygen species-mediated damage to mitochondrial DNA in children with typical autism  

E-Print Network [OSTI]

1997:77–102. 3. Lin MT, Beal MF: Mitochondrial dysfunction13:262–270. 5. Albers DS, Beal MF: Mitochondrial dysfunctionAMS, Mecocci P, Cormio A, Beal MF, Cherubini A, Cantatore P,

Napoli, Eleonora; Wong, Sarah; Giulivi, Cecilia

2013-01-01T23:59:59.000Z

223

Prediction of blast damage from vapor cloud explosions  

SciTech Connect (OSTI)

The process industries handle a wide range of different materials and use them in different types of chemical reaction. Of particular concern is the prospect of damage and injury affecting the general public outside the boundary wall of the chemical plant. It is not wise to permit the construction of homes, schools or hospitals so close to chemical plants that they, and the people within, might be damaged or injured should there be an accidental explosion in the plant. The major hazard outside the plant is over-pressure, a consequence of an accidental explosion in a cloud of flammable gas or vapor (Vapor Cloud Explosion or VCE). It is the responsibility of plant management to ensure that any such accidental explosion is not so large as to endanger the public, and of the local planning authorities to ensure that homes, schools or hospitals are not sited so close to chemical plants that they may be endangered by accidental explosion. A vital tool for such authorities is a simple method of assessing the possible consequences of an accidental VCE. In this paper those methods of assessing the consequences are examined.

Phillips, H. [Phillips (H.), Buxton (United Kingdom)

1995-12-31T23:59:59.000Z

224

Implications for Damage Recognition during Dpo4-Mediated Mutagenic Bypass of m1G and m3C Lesions  

SciTech Connect (OSTI)

DNA is susceptible to alkylation damage by a number of environmental agents that modify the Watson-Crick edge of the bases. Such lesions, if not repaired, may be bypassed by Y-family DNA polymerases. The bypass polymerase Dpo4 is strongly inhibited by 1-methylguanine (m1G) and 3-methylcytosine (m3C), with nucleotide incorporation opposite these lesions being predominantly mutagenic. Further, extension after insertion of both correct and incorrect bases, introduces additional base substitution and deletion errors. Crystal structures of the Dpo4 ternary extension complexes with correct and mismatched 3'-terminal primer bases opposite the lesions reveal that both m1G and m3C remain positioned within the DNA template/primer helix. However, both correct and incorrect pairing partners exhibit pronounced primer terminal nucleotide distortion, being primarily evicted from the DNA helix when opposite m1G or misaligned when pairing with m3C. Our studies provide insights into mechanisms related to hindered and mutagenic bypass of methylated lesions and models associated with damage recognition by repair demethylases.

Rechkoblit, Olga; Delaney, James C.; Essigmann, John M.; Patel, Dinshaw J. (MIT); (MSKCC)

2012-05-08T23:59:59.000Z

225

Damage detection technique by measuring laser-based mechanical impedance  

SciTech Connect (OSTI)

This study proposes a method for measurement of mechanical impedance using noncontact laser ultrasound. The measurement of mechanical impedance has been of great interest in nondestructive testing (NDT) or structural health monitoring (SHM) since mechanical impedance is sensitive even to small-sized structural defects. Conventional impedance measurements, however, have been based on electromechanical impedance (EMI) using contact-type piezoelectric transducers, which show deteriorated performances induced by the effects of a) Curie temperature limitations, b) electromagnetic interference (EMI), c) bonding layers and etc. This study aims to tackle the limitations of conventional EMI measurement by utilizing laser-based mechanical impedance (LMI) measurement. The LMI response, which is equivalent to a steady-state ultrasound response, is generated by shooting the pulse laser beam to the target structure, and is acquired by measuring the out-of-plane velocity using a laser vibrometer. The formation of the LMI response is observed through the thermo-mechanical finite element analysis. The feasibility of applying the LMI technique for damage detection is experimentally verified using a pipe specimen under high temperature environment.

Lee, Hyeonseok; Sohn, Hoon [Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (Daehak-ro 291, Yuseong-gu, Daejeon 305-701) (Korea, Republic of)

2014-02-18T23:59:59.000Z

226

Density Functional Theory Models for Radiation Damage  

E-Print Network [OSTI]

Density Functional Theory Models for Radiation Damage S.L. Dudarev EURATOM/CCFE Fusion Association, DFT Abstract Density functional theory models developed over the past decade provide unique phenomena. Density functional theory models have effectively created a new paradigm for the scientific

227

Gas condensate damage in hydraulically fractured wells  

E-Print Network [OSTI]

of this research are a step forward in helping to improve the management of gas condensate reservoirs by understanding the mechanics of liquid build-up. It also provides methodology for quantifying the condensate damage that impairs linear flow of gas...

Reza, Rostami Ravari

2004-11-15T23:59:59.000Z

228

The Status of Radiation Damage Experiments  

SciTech Connect (OSTI)

Experiments have been on-going for about two years to determine the effects that radiation damage have on the physical and chemical properties of candidate titanate ceramics for the immobilization of plutonium. We summarize the results of these experiments in this document.

Strachan, Denis M.; Scheele, Randall D.; Icenhower, Jonathan P.; Kozelisky, Anne E.; Sell, Richard L.; Legore, Virginia L.; Schaef, Herbert T.; O'Hara, Matthew J.; Brown, Christopher F.; Buchmiller, William C.

2001-11-20T23:59:59.000Z

229

A damage mechanics approach to life prediction for a salt structure  

SciTech Connect (OSTI)

Excavated rooms in natural bedded salt formations are being considered for use as repositories for nuclear waste. It is presumed that deformation of the rooms by creep will lead to loss of structural integrity and affect room life history and seal efficiency. At projected repository temperatures, two possible fracture mechanisms in salt are creep-induced microcracking in triaxial compression and cleavage in tension. Thus, an accurate prediction of room life and seal degradation requires a reliable description of the creep and damage processes. While several constitutive models that treat either creep or fracture in salt are available in the literature, very few models have considered creep and damage in a coupled manner. Previously, Munson and Dawson formulated a set of creep equations for salt based on the consideration of dislocation mechanisms in the creep process. This set of creep equations has been generalized to include continuum, isotropic damage as a fully coupled variable in the response equation. The extended model has been referred to as the Multimechanism Deformation Coupled Fracture (MDCF) model. A set of material constants for the creep and damage terms was deduced based on test data for both clean and argillaceous salt. In this paper, the use of the MDCF model for establishing the failure criteria and for analyzing the creep response of a salt structure is demonstrated. The paper is divided into three parts. A summary of the MDCF model is presented first, which is followed by an evaluation of the MDCF model against laboratory data. Finally, finite-element calculations of the creep and damage response of a salt structure are presented and compared against in-situ field measurements.

Chan, K.S.; Bodner, S.R. [Southwest Research Inst., San Antonio, TX (United States); DeVries, K.L.; Fossum, A.F. [RE/SPEC, Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

1995-03-01T23:59:59.000Z

230

A Model for Structure and Thermodynamics of ssDNA and dsDNA Near...  

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

Structure and Thermodynamics of ssDNA and dsDNA Near a Surface:A Coarse Grained Approach. A Model for Structure and Thermodynamics of ssDNA and dsDNA Near a Surface:A Coarse...

231

Imaging System to Measure Kinetics of Material Cluster Ejection During Exit-Surface Damage Initiation and Growth in Fused Silica  

SciTech Connect (OSTI)

Laser-induced damage on the surface of optical components typically is manifested by the formation of microscopic craters that can ultimately degrade the optics performance characteristics. It is believed that the damage process is the result of the material exposure to high temperatures and pressures within a volume on the order of several cubic microns located just below the surface. The response of the material following initial localized energy deposition by the laser pulse, including the timeline of events and the individual processes involved during this timeline, is still largely unknown. In this work we introduce a time-resolved microscope system designed to enable a detailed investigation of the sequence of dynamic events involved during surface damage. To best capture individual aspects of the damage timeline, this system is employed in multiple imaging configurations (such as multi-view image acquisition at a single time point and multi-image acquisition at different time points of the same event) and offers sensitivity to phenomena at very early delay times. The capabilities of this system are demonstrated with preliminary results from the study of exit-surface damage in fused silica. The time-resolved images provide information on the material response immediately following laser energy deposition, the processes later involved during crater formation or growth, the material ejecta kinetics, and overall material motion and transformation. Such results offer insight into the mechanisms governing damage initiation and growth in the optical components of ICF class laser systems.

Raman, R N; Negres, R A; Demos, S G

2009-10-29T23:59:59.000Z

232

8-oxoguainine enhances bending of DNA that favors binding of glycosylases  

SciTech Connect (OSTI)

Molecular dynamics (MD) simulations were carried out on the DNA oligonucleotide GGGAACAACTAG:CTAGTTGTTCCC in its native form and with guanine in the central G19:C6 base pair replaced by 8-oxoguanine (8oxoG). A box of explicit water molecules was used for solvation and Na+ counterions were added to neutralize the system. The direction and magnitude of global bending were assessed by a technique used previously to analyze simulations of DNA containing a thymine dimer. The presence of 8oxoG did not greatly affect the magnitude of DNA bending; however, bending into the major groove was significantly more probable when 8oxoG replaced G19. Crystal structures of glycosylases bound to damaged-DNA substrates consistently show a sharp bend into the major groove at the damage site. We conclude that changes in bending dynamics that assist the formation of this kink are a part of the mechanism by which glycosylases of the base excision repair pathway recognize the presence of 8oxoG in DNA.

John H. Miller

2003-04-23T23:59:59.000Z

233

Continuum-based Multiscale Computational Damage Modeling of Cementitous Composites  

E-Print Network [OSTI]

of ? , and its comparison with experimental results by Kupfer et al. (1969) ...... 32 5.1 Evolution of the damage due to the change of the compressive hardening modulus Q ? for: (a) Exponential damage evolution law in Eq. (2.48) and (b) power damage... evolution law in Eq. (2.52) ............... 71 5.2 Evolution of the damage due to the change of the compressive hardening rate constant b? for: (a) Exponential damage evolution law in Eq. (2.48) and (b) power damage evolution law in Eq. (2...

Kim, Sun-Myung

2011-08-08T23:59:59.000Z

234

Radiation Damage in Nanostructured Metallic Films  

E-Print Network [OSTI]

with favorable microstructures and to investigate their response to radiation. The goals of this thesis are to study the radiation responses of several nanostructured metallic thin film systems, including Ag/Ni multilayers, nanotwinned Ag and nanocrystalline Fe...

Yu, Kaiyuan

2013-04-15T23:59:59.000Z

235

Forensic DNA data banking by state crime labortaories  

SciTech Connect (OSTI)

This article reports the results of a survey of the responsible crime laboratories in the first 19 states with legislation establishing forensic DNA data banks. The survey inquired into the labs` policies and procedures regarding the collection, storage, and analysis of samples; the retention of samples and data; search protocols; access to samples and data by third parties; and related matters. The research suggests that (1) the number of samples collected from convicted offenders for DNA data banking has far surpassed the number that have been analyzed; (2) data banks have already been used in a small but growing number of cases, to locate suspects and to identify associations between unresolved cases; (3) crime labs currently plan to retain indefinitely the samples collected for their data banks; and (4) the nature and extent of security safeguards that crime labs have implemented for their data banks vary among states. The recently enacted DNA Identification Act (1994) will provide $40 million in federal matching grants to states for DNA analysis activities, so long as states comply with specified quality-assurance standards, submit to external proficiency testing, and limit access to DNA information. Although these additional funds should help to ease some sample backlogs, it remains unclear how labs will allocate the funds, as between analyzing samples for their data banks and testing evidence samples in cases without suspects. The DNA Identification Act provides penalties for the disclosure or obtaining of DNA data held by data banks that participate in CODIS, the FBI`s evolving national network of DNA data banks, but individual crime labs must also develop stringent internal safeguards to prevent breaches of data-bank security. 9 refs., 3 tabs.

McEwen, J.E. [Eunice Kennedy Shrive Center for Mental Retardation, Waltham, MA (United States)

1995-06-01T23:59:59.000Z

236

Autoregressive modeling with state-space embedding vectors for damage detection under operational and environmental variability  

SciTech Connect (OSTI)

A nonlinear time series approach is presented to detect damage in systems by using a state-space reconstruction to infer the geometrical structure of a deterministic dynamical system from observed time series response at multiple locations. The unique contribution of this approach is using a Multivariate Autoregressive (MAR) model of a baseline condition to predict the state space, where the model encodes the embedding vectors rather than scalar time series. A hypothesis test is established that the MAR model will fail to predict future response if damage is present in the test condition, and this test is investigated for robustness in the context of operational and environmental variability. The applicability of this approach is demonstrated using acceleration time series from a base-excited 3-story frame structure.

Farrar, Charles [Los Alamos National Laboratory; Figueiredo, Eloi [UNIV OF PORTO; Todd, Michael [UCSD; Flynn, Eric [UCSD

2010-01-01T23:59:59.000Z

237

Integrated Microfluidic Electrochemical DNA Sensor  

E-Print Network [OSTI]

of small scale fluid flow Laminar flow Easy to predict the flow patterns Very little diffusion This can make mixing difficult Small volumes Don't need to waste expensive reagents Easy fluid control;DNA Purification The DNA will be extracted using Invitrogen Charge Switch beads. Cellular Lysis

Fygenson, Deborah Kuchnir

238

Nonuniform radiation damage in permanent magnet quadrupoles  

SciTech Connect (OSTI)

We present data that indicate nonuniform magnetization loss due to radiation damage in neodymium-iron-boron Halbach-style permanent magnet quadrupoles. The proton radiography (pRad) facility at Los Alamos uses permanent-magnet quadrupoles for magnifying lenses, and a system recently commissioned at GSI-Darmsdadt uses permanent magnets for its primary lenses. Large fluences of spallation neutrons can be produced in close proximity to these magnets when the proton beam is, intentionally or unintentionally, directed into the tungsten beam collimators; imaging experiments at LANL’s pRad have shown image degradation with these magnetic lenses at proton beam doses lower than those expected to cause damage through radiation-induced reduction of the quadrupole strength alone. We have observed preferential degradation in portions of the permanent magnet quadrupole where the field intensity is highest, resulting in increased high-order multipole components.

Danly, C. R.; Merrill, F. E.; Barlow, D.; Mariam, F. G. [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

2014-08-15T23:59:59.000Z

239

Evaluation of radiation damage using nonlinear ultrasound  

SciTech Connect (OSTI)

Nonlinear ultrasound was used to monitor radiation damage in two reactor pressure vessel (RPV) steels. The microstructural changes associated with radiation damage include changes in dislocation density and the formation of precipitates, and nonlinear ultrasonic waves are known to be sensitive to such changes. Six samples each of two different RPV steels were previously irradiated in the Rheinsberg power reactor to two fluence levels, up to 10{sup 20} n/cm{sup 2} (E > 1 MeV). Longitudinal waves were used to measure the acoustic nonlinearity in these samples, and the results show a clear increase in the measured acoustic nonlinearity from the unirradiated state to the medium dose, and then a decrease from medium dose to high dose.

Matlack, K. H. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Wall, J. J. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Electric Power Research Institute, Charlotte, North Carolina 28262 (United States); Kim, J.-Y. [School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Qu, J. [Department of Civil and Environmental Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Jacobs, L. J. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Viehrig, H.-W. [Department of Structural Materials, Helmholtz Zentrum Dresden-Rossendorf, Institute of Ion-Beam Physics and Materials Research, P.O. Box 510119, 01314 Dresden (Germany)

2012-03-01T23:59:59.000Z

240

Carbon Fiber Damage in Particle Beam  

E-Print Network [OSTI]

Carbon fibers are commonly used as moving targets in beam wire scanners. The heating of the fiber due to energy loss of the particles travelling through is simulated with Geant4. The heating induced by the beam electromagnetic field is estimated with ANSYS. The heat transfer and sublimation processes are modelled. Due to the model nonlinearity, a numerical approach based on discretization of the wire movement is used to solve it for particular beams. Radiation damage to the fiber is estimated with SRIM. The model is tested with available SPS and LEP data and a dedicated damage test on the SPS beam is performed followed by a post-mortem analysis of the wire remnants. Predictions for the LHC beams are made.

Dehning, B; Kroyer, T; Meyer, M; Sapinski, M

2011-01-01T23:59:59.000Z

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


241

Damage analysis in asphalt concrete mixtures based on parameter relationships  

E-Print Network [OSTI]

Asphalt pavements experience damage due to traffic loading under various environmental conditions. Damage can be caused by viscopl microcracks, fracture due to fatigue cracking, or fracture due to thermal cracking. Asphalt pavements have...

Song, Injun

2004-11-15T23:59:59.000Z

242

A BAYESIAN PROBABILISTIC APPROACH TO DAMAGE DETECTION FOR CIVIL  

E-Print Network [OSTI]

damage or other environmental e ects. Results based on the eld vibration test of a bridge indicate on the vibration parameters can be di erentiated from other environmental e ects or potential structural damage. vA BAYESIAN PROBABILISTIC APPROACH TO DAMAGE DETECTION FOR CIVIL STRUCTURES a dissertation submitted

Stanford University

243

25.99.99.Q0.05 Damage to University Property Page 1 of 2 STANDARD ADMINISTRATIVE PROCEDURE  

E-Print Network [OSTI]

25.99.99.Q0.05 Damage to University Property Page 1 of 2 STANDARD ADMINISTRATIVE PROCEDURE 25, 2015 Standard Administrative Procedure Statement The responsibility for the care of all University and the Building Operations Department and the Department of Student Affairs. The Directors and Program Chairs

244

Mechanical Damage from Cavitation in High Intensity Focused Ultrasound Accelerated Thrombolysis  

E-Print Network [OSTI]

for Mechanical Damage . . . . . . . . . . . . . . . .3.3.3 Connection to Mechanical Damage . . . . . . 3.41.2.5 Assessing mechanical damage . . 1.3 Bubble

Weiss, Hope

2012-01-01T23:59:59.000Z

245

Induction and Persistence of Large ?H2AX Foci by High Linear Energy Transfer Radiation in DNA-Dependent protein kinase–Deficient Cells  

SciTech Connect (OSTI)

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

Bracalente, Candelaria; Ibañez, Irene L. [Departamento de Micro y Nanotecnología, Comisión Nacional de Energía Atómica, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Molinari, Beatriz [Departamento de Radiobiología, Comisión Nacional de Energía Atómica, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Palmieri, Mónica [Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires (Argentina); Kreiner, Andrés [Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Gerencia de Investigación y Aplicaciones, Comisión Nacional de Energía Atómica, San Martín, Buenos Aires (Argentina); Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, San Martín, Buenos Aires (Argentina); Valda, Alejandro [Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, San Martín, Buenos Aires (Argentina); and others

2013-11-15T23:59:59.000Z

246

Natural Resource Damage Assessment Cooperation and Integration  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), 42 U.S.C. 9601, et seq., Executive Order 12580, and CERCLA's implementing regulations in the National Contingency Plan (NCP), 40 CFR Part 300, give the DOE three roles at DOE facilities undergoing environmental cleanup: lead response agency, natural resource trustee, and the party responsible for releases and threatened releases of hazardous substances. Does not cancel other directives.

2012-06-19T23:59:59.000Z

247

DNA UPTAKE BY TRANSFORMABLE BACTERIA  

SciTech Connect (OSTI)

The various processes of DNA uptake by cells can be categorized as: viral DNA entry, conjugation, or transformation. Within each category, a variety of mechanisms have been found. However, considerable similarities occur among the different mechanisms of conjugation and, especially, transformation. All of these natural mechanisms of DNA transfer are quite elaborate and involve multiple protein components, as the case may be, of the virus, the donor cell, and the recipient cell. The mechanisms of viral infection and conjugation will be discussed mainly with respect to their relevance to transformation.

LACKS,S.A.

1999-09-07T23:59:59.000Z

248

Sequence independent amplification of DNA  

DOE Patents [OSTI]

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

Bohlander, S.K.

1998-03-24T23:59:59.000Z

249

Sequence independent amplification of DNA  

DOE Patents [OSTI]

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

Bohlander, Stefan K. (Chicago, IL)

1998-01-01T23:59:59.000Z

250

Normalized cDNA libraries  

DOE Patents [OSTI]

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3' noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library.

Soares, Marcelo B. (New York, NY); Efstratiadis, Argiris (Englewood, NJ)

1997-01-01T23:59:59.000Z

251

Normalized cDNA libraries  

DOE Patents [OSTI]

This invention provides a method to normalize a directional cDNA library constructed in a vector that allows propagation in single-stranded circle form comprising: (a) propagating the directional cDNA library in single-stranded circles; (b) generating fragments complementary to the 3{prime} noncoding sequence of the single-stranded circles in the library to produce partial duplexes; (c) purifying the partial duplexes; (d) melting and reassociating the purified partial duplexes to moderate Cot; and (e) purifying the unassociated single-stranded circles, thereby generating a normalized cDNA library. 4 figs.

Soares, M.B.; Efstratiadis, A.

1997-06-10T23:59:59.000Z

252

Delay-active damage versus non-local enhancement for anisotropic damage dynamics computations with alternated loading  

E-Print Network [OSTI]

of anisotropic visco-damage, by introducing a material strain rate effect in the cases of positive hydro- static: anisotropic damage, concrete, non-local, visco-damage, micro-cracks closure Email address: desmorat such as concrete are mainly governed by the nucleation and the propagation of micro-cracks. Present within

253

Slow elimination of phosphorylated histone {gamma}-H2AX from DNA of terminally differentiated mouse heart cells in situ  

SciTech Connect (OSTI)

Phosphorylation of replacement histone H2AX occurs in megabase chromatin domains around double-strand DNA breaks (DSBs) and this modification (called {gamma}-H2AX) may serve as a useful marker of genome damage and repair in terminally differentiated cells. Here using immunohistochemistry we studied kinetics of {gamma}-H2AX formation and elimination in the X-irradiated mouse heart and renal epithelial tissues in situ. Unirradiated tissues have 3-5% {gamma}-H2AX-positive cells and in tissues fixed 1 h after X-irradiation {gamma}-H2AX-positive nuclei are induced in a dose-dependent manner approaching 20-30% after 3 Gy of IR. Analysis of mouse tissues at different times after 3 Gy of IR showed that maximal induction of {gamma}-H2AX in heart is observed 20 min after IR and then is decreased slowly with about half remaining 23 h later. In renal epithelium maximum of the {gamma}-H2AX-positive cells is observed 40 min after IR and then decreases to control values in 23 h. This indicates that there are significant variations between non-proliferating mammalian tissues in the initial H2AX phosphorylation rate as well as in the rate of {gamma}-H2AX elimination after X-irradiation, which should be taken into account in the analysis of radiation responses.

Gavrilov, Boris [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation); Vezhenkova, Irina [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation); Firsanov, Denis [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation); Solovjeva, Liudmila [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation); Svetlova, Maria [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation); Mikhailov, Vyacheslav [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation); Tomilin, Nikolai [Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg (Russian Federation)]. E-mail: nvtom@hotmail.com

2006-09-08T23:59:59.000Z

254

Damage of MEMS thermal actuators heated by laser irradiation.  

SciTech Connect (OSTI)

Optical actuation of microelectromechanical systems (MEMS) is advantageous for applications for which electrical isolation is desired. Thirty-two polycrystalline silicon opto-thermal actuators, optically-powered MEMS thermal actuators, were designed, fabricated, and tested. The design of the opto-thermal actuators consists of a target for laser illumination suspended between angled legs that expand when heated, providing the displacement and force output. While the amount of displacement observed for the opto-thermal actuators was fairly uniform for the actuators, the amount of damage resulting from the laser heating ranged from essentially no damage to significant amounts of damage on the target. The likelihood of damage depended on the target design with two of the four target designs being more susceptible to damage. Failure analysis of damaged targets revealed the extent and depth of the damage.

Walraven, Jeremy Allen; Klody, Kelly Anne; Sackos, John T.; Phinney, Leslie Mary

2004-11-01T23:59:59.000Z

255

Damage of MEMS thermal actuators heated by laser irradiation.  

SciTech Connect (OSTI)

Optical actuation of microelectromechanical systems (MEMS) is advantageous for applications for which electrical isolation is desired. Thirty-two polycrystalline silicon opto-thermal actuators, optically-powered MEMS thermal actuators, were designed, fabricated, and tested. The design of the opto-thermal actuators consists of a target for laser illumination suspended between angled legs that expand when heated, providing the displacement and force output. While the amount of displacement observed for the opto-thermal actuators was fairly uniform for the actuators, the amount of damage resulting from the laser heating ranged from essentially no damage to significant amounts of damage on the target. The likelihood of damage depended on the target design with two of the four target designs being more susceptible to damage. Failure analysis of damaged targets revealed the extent and depth of the damage.

Walraven, Jeremy Allen; Klody, Kelly Anne; Sackos, John T.; Phinney, Leslie Mary

2005-01-01T23:59:59.000Z

256

Survey of four damage models for concrete.  

SciTech Connect (OSTI)

Four conventional damage plasticity models for concrete, the Karagozian and Case model (K&C), the Riedel-Hiermaier-Thoma model (RHT), the Brannon-Fossum model (BF1), and the Continuous Surface Cap Model (CSCM) are compared. The K&C and RHT models have been used in commercial finite element programs many years, whereas the BF1 and CSCM models are relatively new. All four models are essentially isotropic plasticity models for which 'plasticity' is regarded as any form of inelasticity. All of the models support nonlinear elasticity, but with different formulations. All four models employ three shear strength surfaces. The 'yield surface' bounds an evolving set of elastically obtainable stress states. The 'limit surface' bounds stress states that can be reached by any means (elastic or plastic). To model softening, it is recognized that some stress states might be reached once, but, because of irreversible damage, might not be achievable again. In other words, softening is the process of collapse of the limit surface, ultimately down to a final 'residual surface' for fully failed material. The four models being compared differ in their softening evolution equations, as well as in their equations used to degrade the elastic stiffness. For all four models, the strength surfaces are cast in stress space. For all four models, it is recognized that scale effects are important for softening, but the models differ significantly in their approaches. The K&C documentation, for example, mentions that a particular material parameter affecting the damage evolution rate must be set by the user according to the mesh size to preserve energy to failure. Similarly, the BF1 model presumes that all material parameters are set to values appropriate to the scale of the element, and automated assignment of scale-appropriate values is available only through an enhanced implementation of BF1 (called BFS) that regards scale effects to be coupled to statistical variability of material properties. The RHT model appears to similarly support optional uncertainty and automated settings for scale-dependent material parameters. The K&C, RHT, and CSCM models support rate dependence by allowing the strength to be a function of strain rate, whereas the BF1 model uses Duvaut-Lion viscoplasticity theory to give a smoother prediction of transient effects. During softening, all four models require a certain amount of strain to develop before allowing significant damage accumulation. For the K&C, RHT, and CSCM models, the strain-to-failure is tied to fracture energy release, whereas a similar effect is achieved indirectly in the BF1 model by a time-based criterion that is tied to crack propagation speed.

Leelavanichkul, Seubpong (University of Utah, Salt Lake City, UT); Brannon, Rebecca Moss (University of Utah, Salt Lake City, UT)

2009-08-01T23:59:59.000Z

257

Minimizing radiation damage in nonlinear optical crystals  

DOE Patents [OSTI]

Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal.

Cooke, D. Wayne (Santa Fe, NM); Bennett, Bryan L. (Los Alamos, NM); Cockroft, Nigel J. (Santa Fe, NM)

1998-01-01T23:59:59.000Z

258

Minimizing radiation damage in nonlinear optical crystals  

DOE Patents [OSTI]

Methods are disclosed for minimizing laser induced damage to nonlinear crystals, such as KTP crystals, involving various means for electrically grounding the crystals in order to diffuse electrical discharges within the crystals caused by the incident laser beam. In certain embodiments, electrically conductive material is deposited onto or into surfaces of the nonlinear crystals and the electrically conductive surfaces are connected to an electrical ground. To minimize electrical discharges on crystal surfaces that are not covered by the grounded electrically conductive material, a vacuum may be created around the nonlinear crystal. 5 figs.

Cooke, D.W.; Bennett, B.L.; Cockroft, N.J.

1998-09-08T23:59:59.000Z

259

Radiation damage evolution in ceramics. | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 -the Mid-Infrared at 278, 298, and 323 RS-PO-0001-001.docW.Radiation damage

260

Modeling DNA Shuffling Fengzhu Sun  

E-Print Network [OSTI]

Modeling DNA Shuffling Fengzhu Sun 1Department of Genetics Emory University School of Medicine property are selected. Irvine et al. (1991) and Sun et al. (1996) studied in vitro evolution not involving

Sun, Fengzhu - Sun, Fengzhu

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


261

Unnatural nucleotides for DNA sequencing  

E-Print Network [OSTI]

Fluorescent nucleotide analogs were prepared and tested to find surrogate structures that are: (i) incorporated by DNA polymerases; (ii) spectroscopically distinct for each fluorescent tag; and (iii) easily deprotected at the 3'-position under mild...

Jacutin, Swanee E

1997-01-01T23:59:59.000Z

262

CORRELATION OF DNA METHYLATION WITH MERCURY CONTAMINATION IN MARINE ORGANISMS: A CASE STUDY OF NOAA MUSSEL WATCH TISSUE SAMPLES  

E-Print Network [OSTI]

American oysters (Crassostrea virginica) obtained from the NOAA Mussel Watch program were screened for DNA methylation, a type of epigenetic response to stressors. Oysters were collected from sites in the Gulf of Mexico having high mercury...

Brinkmeyer, Robin; Taylor, Robert; Germ, Kaylyn E.

2011-08-04T23:59:59.000Z

263

Molecular Computing with DNA Self-Assembly  

E-Print Network [OSTI]

Molecular Computing with DNA Self-Assembly Urmi Majumder #12;Self-Assembly in Nature #12;Key to DNA for Molecular Computing with DNA Self-Assembly Compact: Small library of assembly primitives Complex: Capable in Tiling Assembly: vitroation tural DNA self-assembly has powerful echanisms for error correction

Reif, John H.

264

Low energy electron stimulated desorption from DNA films dosed with oxygen  

SciTech Connect (OSTI)

Desorption of anions stimulated by 1-18 eV electron impact on self-assembled monolayer (SAM) films of single DNA strands is measured as a function of film temperature (50-250 K). The SAMs, composed of 10 nucleotides, are dosed with O{sub 2}. The OH{sup -} desorption yields increase markedly with exposure to O{sub 2} at 50 K and are further enhanced upon heating. In contrast, the desorption yields of O{sup -}, attributable to dissociative electron attachment to trapped O{sub 2} molecules decrease with heating. Irradiation of the DNA films prior to the deposition of O{sub 2} shows that this surprising increase in OH{sup -} desorption, at elevated temperatures, arises from the reaction of O{sub 2} with damaged DNA sites. These results thus appear to be a manifestation of the so-called 'oxygen fixation' effect, well known in radiobiology.

Mirsaleh-Kohan, Nasrin; Bass, Andrew D.; Cloutier, Pierre; Massey, Sylvain; Sanche, Leon [Groupe en sciences des radiations, Faculte de medecine et des sciences de la sante, Universite de Sherbrooke, Sherbrooke, Quebec J1H 5N4 (Canada)

2012-06-21T23:59:59.000Z

265

Identification of new functions for BRCT domains  

E-Print Network [OSTI]

Our lab identified the tandem BRCT domains of PTIP function as a DNA damage responsive phospho binding domain that recognizes proteins phosphorylated by ATM and ATR after DNA damage. The PTIP tandem BRCT domains are ...

Mohammad, Duaa H

2008-01-01T23:59:59.000Z

266

E-Print Network 3.0 - acid-induced growth arrest Sample Search...  

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

of the ATR-mediated DNA Damage Response by the HIV-1 Viral Protein R* Summary: , Salt Lake City, Utah 84132 DNA damage is a universal inducer of cell cycle arrest at the G2...

267

Extraction of PCR-amplifiable genomic DNA from Bacillus anthracisspores  

SciTech Connect (OSTI)

Bacterial endospore disruption and nucleic acid extractionresulting in DNA of PCR-amplifiable quality and quantity are not trivial.Responding to the needs of the Hazardous Materials Response Unit (HMRU),Laboratory Division, Federal Bureau of Investigation, protocols weredeveloped to close these gaps. Effectiveness and reproducibility of thetechniques were validated with laboratory grown pure spores of Bacillusanthracis and its close phylogenetic neighbors, and with spiked soils anddamaged samples.

Torok, Tamas

2003-05-19T23:59:59.000Z

268

DNA polymorphism identity determination using flow cytometry  

DOE Patents [OSTI]

DNA polymorphism identity determination using flow cytometry. Primers designed to be immobilized on microspheres are allowed to anneal to the DNA strand under investigation, and are extended by either DNA polymerase using fluorescent dideoxynucleotides or ligated by DNA ligase to fluorescent reporter oligonucleotides. The fluorescence of either the dideoxynucleotide or the reporter oligonucleotide attached to the immobilized primer is measured by flow cytometry, thereby identifying the nucleotide polymorphism on the DNA strand.

Nolan, John P. (Santa Fe, NM); White, P. Scott (Los Alamos, NM); Cai, Hong (Los Alamos, NM)

2001-01-01T23:59:59.000Z

269

7th International Workshop on Microbeam Probes of Cellular Radiation Response  

SciTech Connect (OSTI)

The extended abstracts that follow present a summary of the Proceedings of the 7th International Workshop: Microbeam Probes of Cellular Radiation Response, held at Columbia University’s Kellogg Center in New York City on March 15–17, 2006. These International Workshops on Microbeam Probes of Cellular Radiation Response have been held regularly since 1993 (1–5). Since the first workshop, there has been a rapid growth (see Fig. 1) in the number of centers developing microbeams for radiobiological research, and worldwide there are currently about 30 microbeams in operation or under development. Single-cell/single-particle microbeam systems can deliver beams of different ionizing radiations with a spatial resolution of a few micrometers down to a few tenths of a micrometer. Microbeams can be used to addressquestions relating to the effects of low doses of radiation (a single radiation track traversing a cell or group of cells), to probe subcellular targets (e.g. nucleus or cytoplasm), and to address questions regarding the propagation of information about DNA damage (for example, the radiation-induced bystander effect). Much of the recent research using microbeams has been to study low-dose effects and ‘‘non-targeted’’ responses such as bystander effects, genomic instability and adaptive responses. This Workshop provided a forum to assess the current state of microbeam technology and current biological applications and to discuss future directions for development, both technological and biological. Over 100 participants reviewed the current state of microbeam research worldwide and reported on new technological developments in the fields of both physics and biology.

Brenner, David J.

2009-07-21T23:59:59.000Z

270

A damage mechanics based approach to structural deterioration and reliability  

SciTech Connect (OSTI)

Structural deterioration often occurs without perceptible manifestation. Continuum damage mechanics defines structural damage in terms of the material microstructure, and relates the damage variable to the macroscopic strength or stiffness of the structure. This enables one to predict the state of damage prior to the initiation of a macroscopic flaw, and allows one to estimate residual strength/service life of an existing structure. The accumulation of damage is a dissipative process that is governed by the laws of thermodynamics. Partial differential equations for damage growth in terms of the Helmholtz free energy are derived from fundamental thermodynamical conditions. Closed-form solutions to the equations are obtained under uniaxial loading for ductile deformation damage as a function of plastic strain, for creep damage as a function of time, and for fatigue damage as function of number of cycles. The proposed damage growth model is extended into the stochastic domain by considering fluctuations in the free energy, and closed-form solutions of the resulting stochastic differential equation are obtained in each of the three cases mentioned above. A reliability analysis of a ring-stiffened cylindrical steel shell subjected to corrosion, accidental pressure, and temperature is performed.

Bhattcharya, B.; Ellingwood, B. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Civil Engineering

1998-02-01T23:59:59.000Z

271

Integrating Natural Resource Damage Assessment and environmental restoration activities at DOE facilities  

SciTech Connect (OSTI)

Environmental restoration activities are currently under way at several sites owned by the US Department of Energy (DOE) under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended. DOE is the CERCLA lead response agency for these activities. Section 120(a) of the Superfund Amendments and Reauthorization Act also subjects DOE to liability under Section 107 of CERCLA for natural resource damages resulting from hazardous substance releases at its sites. The Natural Resource Damage Assessment (NRDA) process, by which natural resource injuries are determined and compensatory monetary damages are calculated, is not well known or understood by DOE staff and contractors involved in environmental restoration activities. Nevertheless, natural resource liabilities are potentially a significant source of additional monetary claims for CERCLA hazardous substance releases. This paper describes the requirements of NRDA and explains how to integrate the NRDA and CERCLA Remedial Investigation/Feasibility Study processes, in order to more quickly restore environmental services at the lowest total cost to the public. The first section of the paper explains the statutory and regulatory mandates for the NRDA process. The second section briefly describes the four phases of the NRDA process, while the third section examines the three steps in the assessment phase in considerable detail. Finally, the last section focuses on the integration of the CERCLA and NRDA processes.

Bascietto, J.J. [Dept. of Energy, Washington, DC (US). RCRA/CERCLA Div.; Dunford, R.W. [Research Triangle Inst., Research Triangle Park, NC (US); Sharples, F.E.; Suter, G.W. II [Oak Ridge National Lab., TN (US)

1993-06-01T23:59:59.000Z

272

Identification of Intrinsic Order and Disorder in the DNA Repair Protein XPA  

SciTech Connect (OSTI)

The damage recognition protein XPA is required to recognize a wide variety of bulky lesions during nucleotide excision repair (NER). Independent NMR solution structures of a human XPA protein (hXPA) fragment comprising approximately one-third of the full-length protein, the minimal DNA-binding domain (MBD), revealed that ~30% of the molecule was structurally disordered. To better characterize structural features of XPA, we performed time-resolved trypsin proteolysis on active, full-length recombinant Xenopus XPA protein (xXPA). The resulting proteolytic fragments were analyzed by electrospray ionization interface coupled to a Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry, SDS-polyacrylamide gel electrophoresis (PAGE), and selected N-terminal sequence determinations. The mass spectrum of the full-length xXPA was consistent with the predicted sequence, 30922.02 vs. 30922.45 Da; respectively. Moreover, the mass spectrometric data allowed the assignment of multiple xXPA fragments not resolvable by SDS PAGE. Full-length xXPA exhibited aberrant mobility on SDS-PAGE with an apparent MW of ~40 kDa. To test predictions that a Glu-rich region (E70-E76) or other local regions of high charge were responsible for this ~40% aberrant SDS-PAGE mobility, the MW's of partial proteolytic fragments from ~5 to 25 kDa precisely determined by ESI-FTICR MS were correlated with their gel positions. Surprisingly, all tested partial tryptic fragments within this size-range exhibited 10-42% divergence between calculated MW and that estimated by SDS-PAGE, thus indicating the origin of anomalous migration of XPA is not localized. The computer program Predictor of Natural Disordered Regions (PONDR) correctly identified several regions of xXPA either sensitive or resistant to partial proteolysis, thereby indicating that disorder in XPA shares sequence features with other well-characterized intrinsically unstructured proteins.

Iakoucheva, Lilia M.; Kimzey, Amy L.; Masselon, Christophe D.; Bruce, James E.; Garner, Ethan C.; Brown, Celeste J.; Dunker, A. K.; Smith, Richard D.; Ackerman, Eric J.

2001-03-01T23:59:59.000Z

273

Does complex absorption behavior leading to conditioning and damage in KDP/DKDP reflect the electronic structure of initiators?  

SciTech Connect (OSTI)

Currently, most of our thinking about the defects responsible for initiating laser damage considers them as featureless absorbers. However, an increasing body of evidence, particularly involving multi-wavelength irradiation, suggests electronic structure of damage initiators is important in determining both initiation and conditioning behaviors in KDP. The effective absorption coefficient of energy under multi-wavelength irradiation cannot be accounted for by a structureless absorber, but is consistent with an initiator with a multi-level structure. We outline the evidence and assess the ability of such a simple multi-level model to explain these and other experimentally observed behaviors.

Feit, M D; DeMange, P P; Negres, R A; Rubenchik, A M; Demos, S G

2007-10-24T23:59:59.000Z

274

Damage from the impacts of small asteroids  

SciTech Connect (OSTI)

The fragmentation of a small asteroid in the atmosphere greatly increases its aerodynamic drag and rate of energy dissipation. The differential atmospheric pressure across it disperses its fragments at a velocity that increases with atmospheric density and impact velocity and decreases with asteroid density. Extending our previous work, we use a spherical atmosphere and a fitted curve to its density profile to find the damage done by an asteroid entering the atmosphere at various zenith angles. In previous work we estimated the blast damage by scaling from data on nuclear explosions in the atmosphere during the 1940s, 1950s and early 1960s. This underestimated the blast from asteroid impacts because nuclear fireballs radiate away a larger fraction of their energy than do meteors, so less of their energy goes into the blast wave. We have redone the calculations to allow for this effect. We have found the area of destruction around the impact point in which the over pressure in the blast wave exceeds 4 pounds/inch{sup 2} = 2.8 X 10{sup 5} dynes/cm{sup 3}, which is enough to knock over trees and destroy buildings. About every 100 years an impactor should blast an area of 300 km{sup 2} or more somewhere on the land area of Earth. The optical flux from asteroids 60 meters or more in diameter is enough to ignite pine forests. However, the blast from an impacting asteroid goes beyond the radius within which the fire starts. It tends to blow out the fire, so it is likely that the impact will char the forest (as at Tunguska), but it will not produce a sustained fire. Because of the atmosphere, asteroids less than about 200 m in diameter are not effective in producing craters and earthquakes. They are also not effective in producing water waves and tsunami in ocean impacts. Tsunami is probably the most devastating type of damage for asteroids that are between 200 meters and 1 km in diameter.

Hills, J.G.; Goda, M.P.

1996-08-15T23:59:59.000Z

275

Radiation Damage in Polarized Ammonia Solids  

E-Print Network [OSTI]

Solid NH3 and ND3 provide a highly polarizable, radiation resistant source of polarized protons and deuterons and have been used extensively in high luminosity experiments investigating the spin structure of the nucleon. Over the past twenty years, the UVA polarized target group has been instrumental in producing and polarizing much of the material used in these studies, and many practical considerations have been learned in this time. In this discussion, we analyze the polarization performance of the solid ammonia targets used during the recent JLab Eg4 run. Topics include the rate of polarization decay with accumulated charge, the annealing procedure for radiation damaged targets to recover polarization, and the radiation induced change in optimum microwave frequency used to polarize the sample. We also discuss the success we have had in implementing frequency modulation of the polarizing microwave frequency.

K. Slifer

2007-11-28T23:59:59.000Z

276

Thermal Decomposition of Radiation-Damaged Polystyrene  

SciTech Connect (OSTI)

The radiation-damaged polystyrene (given the identification name of 'polycube') was fabricated by mixing high-density polystyrene material ("Dylene Fines # 100") with plutonium and uranium oxides. The polycubes were used in the 1960s for criticality studies during processing of spent nuclear fuel. The polycubes have since been stored for almost 40 years at the Hanford Plutonium Finishing Plant (PFP) after failure of two processes to reclaim the plutonium and uranium oxides from the polystyrene matrix. Thermal decomposition products from this highly cross-linked polystyrene matrix were characterized using Gas Chromatograph/Mass Spectroscopy (GC/MS) system coupled to a horizontal furnace. The decomposition studies were performed in air and helium atmospheres at about 773 K. The volatile and semi-volatile organic products for the radiation-damaged polystyrene were different compared to virgin polystyrene. The differences were in the number of organic species generated and their concentrations. In the inert (i.e., helium) atmosphere, the major volatile organic products identified (in order of decreasing concentrations) were styrene, benzene, toluene, ethylbenzene, xylene, nathphalene, propane, .alpha.-methylbenzene, indene and 1,2,3-trimethylbenzene. But in air, the major volatile organic species identified changed slightly. Concentrations of the organic species in the inert atmosphere were significantly higher than those for the air atmosphere processing. Overall, 38 volatile organic species were identified in the inert atmosphere compared to 49 species in air. Twenty of the 38 species in the inert conditions were also products in the air atmosphere. Twenty-two oxidized organic products were identified during thermal processing in air.

Abrefah, John; Klinger, George S.

2000-09-26T23:59:59.000Z

277

Thermal Decomposition of Radiation-Damaged Polystyrene  

SciTech Connect (OSTI)

The radiation-damaged polystyrene material (''polycube'') used in this study was synthesized by mixing a high-density polystyrene (''Dylene Fines No. 100'') with plutonium and uranium oxides. The polycubes were used on the Hanford Site in the 1960s for criticality studies to determine the hydrogen-to-fissile atom ratios for neutron moderation during processing of spent nuclear fuel. Upon completion of the studies, two methods were developed to reclaim the transuranic (TRU) oxides from the polymer matrix: (1) burning the polycubes in air at 873 K; and (2) heating the polycubes in the absence of oxygen and scrubbing the released monomer and other volatile organics using carbon tetrachloride. Neither of these methods was satisfactory in separating the TRU oxides from the polystyrene. Consequently, the remaining polycubes were sent to the Hanford Plutonium Finishing Plant (PFP) for storage. Over time, the high dose of alpha and gamma radiation has resulted in a polystyrene matrix that is highly cross-linked and hydrogen deficient and a stabilization process is being developed in support of Defense Nuclear Facility Safety Board Recommendation 94-1. Baseline processes involve thermal treatment to pyrolyze the polycubes in a furnace to decompose the polystyrene and separate out the TRU oxides. Thermal decomposition products from this degraded polystyrene matrix were characterized by Pacific Northwest National Laboratory to provide information for determining the environmental impact of the process and for optimizing the process parameters. A gas chromatography/mass spectrometry (GC/MS) system coupled to a horizontal tube furnace was used for the characterization studies. The decomposition studies were performed both in air and helium atmospheres at 773 K, the planned processing temperature. The volatile and semi-volatile organic products identified for the radiation-damaged polystyrene were different from those observed for virgin polystyrene. The differences were in the n umber of organic species generated and their concentrations.

J Abrefah GS Klinger

2000-09-26T23:59:59.000Z

278

Conformational Dynamics of Bacteriophage T7 DNA Polymerase and its Processivity Factor, Escherichia coli thioredoxin  

SciTech Connect (OSTI)

Gene 5 of bacteriophage T7 encodes a DNA polymerase (gp5) responsible for the replication of the phage DNA. Gp5 polymerizes nucleotides with low processivity, dissociating after the incorporation of 1 to 50 nucleotides. Thioredoxin (trx) of Escherichia coli binds tightly (Kd = 5 nM) to a unique segment in the thumb subdomain of gp5 and increases processivity. We have probed the molecular basis for the increase in processivity. A single-molecule experiment reveals differences in rates of enzymatic activity and processivity between gp5 and gp5/trx. Small angle X-ray scattering studies combined with nuclease footprinting reveal two conformations of gp5, one in the free state and one upon binding to trx. Comparative analysis of the DNA binding clefts of DNA polymerases and DNA binding proteins show that the binding surface contains more hydrophobic residues than other DNA binding proteins. The balanced composition between hydrophobic and charged residues of the binding site allows for efficient sliding of gp5/trx on the DNA. We propose a model for trx-induced conformational changes in gp5 that enhance the processivity by increasing the interaction of gp5 with DNA.

Akabayov, B.; Akabayov, S; Lee , S; Tabor, S; Kulczyk , A; Richardson, C

2010-01-01T23:59:59.000Z

279

Damage Detection and Characterization in Smart Material Structures \\Lambda y  

E-Print Network [OSTI]

­maps'' as done in the thermal based tomography techniques of [BK1, BK2, BKW] wherein the damaged physical domain

280

attack damage due: Topics by E-print Network  

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

Cell damage extent due to irradiation with nanosecond laser pulses under cell culturing medium and dry environment Engineering Websites Summary: Autnoma de Mxico; Av....

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


281

A matrix damage accumulation model for laminated composites  

E-Print Network [OSTI]

of the evolutionary relationship with respect to either time or the number of loa, d cycles. The damage histories f' or cross-ply laminates subjected to constant maximum stress fatigue were generated by the dart. age evolutionary relationship. These predictions... with respect to the measured damage state. . 5 Structure of FORTRAN code for the integration of the damage evolution- ary rela. tionship. 6 Matrix ' rack damage variable in the 90' plies for a. [Os/90s], AS4/3501 ? 6 laminate loaded at a maximum fatigue...

Lo, David Chi Shing

1990-01-01T23:59:59.000Z

282

Hail Ice Damage of Stringer-Stiffened Curved Composite Panels /  

E-Print Network [OSTI]

Stiffener Impact Damage. Composite Structures 2003;62:213–FTE Values of Carbon/Epoxy Composite Tape Laminate Plates [Sarh B, Kismarton MU. Composite Structures: The First 100

Le, Jacqueline Linh

2013-01-01T23:59:59.000Z

283

assessing tubal damage: Topics by E-print Network  

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

State University, Deborah French, Applied Sciences Associates, Bruce Wright 5 Natural Resource Damage Assessment for the Deepwater BP Oil Spill Environmental Sciences and...

284

Unlimited Damage Accumulation in Metallic Materials Under Cascade-Damage Conditions  

SciTech Connect (OSTI)

Most experiments on neutron or heavy-ion cascade-produced irradiation of pure metals and metallic alloys demonstrate unlimited void growth as well as development of the dislocation structure. In contrast, the theory of radiation damage predicts saturation of void swelling at sufficiently high irradiation doses and, accordingly, termination of accumulation of interstitial-type defects. It is shown in the present paper that, under conditions of steady production of one-dimensionally (1-D) mobile clusters of self-interstitial atoms (SIAs) in displacement cascades, any one of the following three conditions can result in indefinite damage accumulation. First, if the fraction of SIAs generated in the clustered form is smaller than some finite value of the order of the dislocation bias factor. Second, if solute, impurity or transmuted atoms form atmospheres around voids and repel the SIA clusters. Third, if spatial correlations between voids and other defects, such as second-phase precipitates and dislocations, exist that provide shadowing of voids from the SIA clusters. The driving force for the development of such correlations is the same as for void lattice formation and is argued to be always present under cascade-damage conditions. It is emphasised that the mean-free path of 1-D migrating SIA clusters is typically at least an order of magnitude longer than the average distance between microstructural defects; hence spatial correlations on the same scale should be taken into consideration. A way of developing a predictive theory is discussed. An interpretation

Barashev, Aleksandr [University of Liverpool; Golubov, Stanislav I [ORNL

2008-09-01T23:59:59.000Z

285

PHMC post-NPH emergency response training  

SciTech Connect (OSTI)

This document describes post-Natural Phenomena Hazard (NPH) emergency response training that was provided to two teams of Project Hanford Management Contractors (PHMC) staff that will be used to assess potential structural damage that may occur as a result of a significant natural phenomena event. This training supports recent plans and procedures to use trained staff to inspect structures following an NPH event on the Hanford Site.

Conrads, T.J.

1997-04-08T23:59:59.000Z

286

DNA Concentration By UV Spectrophotometry Measure Absorption  

E-Print Network [OSTI]

DNA Concentration By UV Spectrophotometry Measure Absorption: 1. Dilute DNA to 0.5 to 50 µg 2. Measure absorption at 260 nm (A260). Start by zeroing instrument with TE buffer or dH2O alone

Aris, John P.

287

Towards Privacy Preserving of Forensic DNA Databases  

E-Print Network [OSTI]

Protecting privacy of individuals is critical for forensic genetics. In a kinship/identity testing, related DNA profiles between user's query and the DNA database need to be extracted. However, unrelated profiles cannot be revealed to each other...

Liu, Sanmin

2012-02-14T23:59:59.000Z

288

An enhanced Lemaitre model formulation for materials processing damage computation  

E-Print Network [OSTI]

are presented and discussed to deal with complex multiaxial configurations ­ such as multi-stages bulk forming loading, involving crack closure effects. - Simple parameters identification: whatever the damage model used, the identification of damage parameters is an important issue. Most of the time

Boyer, Edmond

289

Evaluation of moisture damage within asphalt concrete mixes  

E-Print Network [OSTI]

Pavements are a major part of the infrastructure in the United States. Moisture damage of these pavements is a significant problem. To predict and prevent this kind of moisture damage a great deal of research has been performed on this issue in past...

Shah, Brij D.

2004-09-30T23:59:59.000Z

290

AFM CHARACTERIZATION OF LASER INDUCED DAMAGE ON CDZNTE CRYSTAL SURFACES  

SciTech Connect (OSTI)

Semi-conducting CdZnTe (or CZT) crystals can be used in a variety of detector-type applications. CZT shows great promise for use as a gamma radiation spectrometer. However, its performance is adversely affected by point defects, structural and compositional heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity), secondary phases and in some cases, damage caused by external forces. One example is damage that occurs during characterization of the surface by a laser during Raman spectroscopy. Even minimal laser power can cause Te enriched areas on the surface to appear. The Raman spectra resulting from measurements at moderate intensity laser power show large increases in peak intensity that is attributed to Te. Atomic Force Microscopy (AFM) was used to characterize the extent of damage to the CZT crystal surface following exposure to the Raman laser. AFM data reveal localized surface damage in the areas exposed to the Raman laser beam. The degree of surface damage to the crystal is dependent on the laser power, with the most observable damage occurring at high laser power. Moreover, intensity increases in the Te peaks of the Raman spectra are observed even at low laser power with little to no visible damage observed by AFM. AFM results also suggest that exposure to the same amount of laser power yields different amounts of surface damage depending on whether the exposed surface is the Te terminating face or the Cd terminating face of CZT.

Hawkins, S; Lucile Teague, L; Martine Duff, M; Eliel Villa-Aleman, E

2008-06-10T23:59:59.000Z

291

Atomic processes during damage production and defect Nasr M. Ghoniem *  

E-Print Network [OSTI]

- sitivity to the deleterious eects of neutron irradiation. Electro-optical properties of semi uncertainties exposed. Damage production under neutron and ion irradiation proceeds through the elementary step-cascade interaction events. Under fusion neutron irradiation, single cascade damage production occurs within 10 ps

Ghoniem, Nasr M.

292

LASER ULTRASONIC IMAGING FOR IMPACT DAMAGE VISUALIZATION IN COMPOSITE STRUCTURE  

E-Print Network [OSTI]

LASER ULTRASONIC IMAGING FOR IMPACT DAMAGE VISUALIZATION IN COMPOSITE STRUCTURE Chao Zhang1 , Jinhao Qiu1* , Hongli Ji1 1 State Key Laboratory of Mechanics and Control of Mechanical Structures ultrasonic scanning technique has great potential for damage evaluation in various applications. In order

Boyer, Edmond

293

Damage detection in mechanical structures using extreme value statistic.  

SciTech Connect (OSTI)

The first and most important objective of any damage identification algorithms is to ascertain with confidence if damage is present or not. Many methods have been proposed for damage detection based on ideas of novelty detection founded in pattern recognition and multivariate statistics. The philosophy of novelty detection is simple. Features are first extracted from a baseline system to be monitored, and subsequent data are then compared to see if the new features are outliers, which significantly depart from the rest of population. In damage diagnosis problems, the assumption is that outliers are generated from a damaged condition of the monitored system. This damage classification necessitates the establishment of a decision boundary. Choosing this threshold value is often based on the assumption that the parent distribution of data is Gaussian in nature. While the problem of novelty detection focuses attention on the outlier or extreme values of the data i.e. those points in the tails of the distribution, the threshold selection using the normality assumption weighs the central population of data. Therefore, this normality assumption might impose potentially misleading behavior on damage classification, and is likely to lead the damage diagnosis astray. In this paper, extreme value statistics is integrated with the novelty detection to specifically model the tails of the distribution of interest. Finally, the proposed technique is demonstrated on simulated numerical data and time series data measured from an eight degree-of-freedom spring-mass system.

Worden, K.; Allen, D. W. (David W.); Sohn, H. (Hoon); Farrar, C. R. (Charles R.)

2002-01-01T23:59:59.000Z

294

Permeability of WIPP Salt During Damage Evolution and Healing  

SciTech Connect (OSTI)

The presence of damage in the form of microcracks can increase the permeability of salt. In this paper, an analytical formulation of the permeability of damaged rock salt is presented for both initially intact and porous conditions. The analysis shows that permeability is related to the connected (i.e., gas accessible) volumetric strain and porosity according to two different power-laws, which may be summed to give the overall behavior of a porous salt with damage. This relationship was incorporated into a constitutive model, known as the Multimechanism Deformation Coupled Fracture (MDCF) model, which has been formulated to describe the inelastic flow behavior of rock salt due to coupled creep, damage, and healing. The extended model was used to calculate the permeability of rock salt from the Waste Isolation Pilot Plant (WIPP) site under conditions where damage evolved with stress over a time period. Permeability changes resulting from both damage development under deviatoric stresses and damage healing under hydrostatic pressures were considered. The calculated results were compared against experimental data from the literature, which indicated that permeability in damaged intact WIPP salt depends on the magnitude of the gas accessible volumetric strain and not on the total volumetric strain. Consequently, the permeability of WIPP salt is significantly affected by the kinetics of crack closure, but shows little dependence on the kinetics of crack removal by sintering.

BODNER,SOL R.; CHAN,KWAI S.; MUNSON,DARRELL E.

1999-12-03T23:59:59.000Z

295

Ris-R-1334(EN) Identification of Damage to Wind  

E-Print Network [OSTI]

Risø-R-1334(EN) Identification of Damage to Wind Turbine Blades by Modal Parameter Estimation April 2002 #12;Risø-R-1334(EN) Identification of Damage to Wind Turbine Blades by Modal Parameter condition monitoring of wind turbine blades (Phase I)". The goal of Phase I is to make a pre

296

Chromosome specific repetitive DNA sequences  

DOE Patents [OSTI]

A method is provided for determining specific nucleotide sequences useful in forming a probe which can identify specific chromosomes, preferably through in situ hybridization within the cell itself. In one embodiment, chromosome preferential nucleotide sequences are first determined from a library of recombinant DNA clones having families of repetitive sequences. Library clones are identified with a low homology with a sequence of repetitive DNA families to which the first clones respectively belong and variant sequences are then identified by selecting clones having a pattern of hybridization with genomic DNA dissimilar to the hybridization pattern shown by the respective families. In another embodiment, variant sequences are selected from a sequence of a known repetitive DNA family. The selected variant sequence is classified as chromosome specific, chromosome preferential, or chromosome nonspecific. Sequences which are classified as chromosome preferential are further sequenced and regions are identified having a low homology with other regions of the chromosome preferential sequence or with known sequences of other family me This invention is the result of a contract with the Department of Energy (Contract No. W-7405-ENG-36).

Moyzis, Robert K. (Los Alamos, NM); Meyne, Julianne (Los Alamos, NM)

1991-01-01T23:59:59.000Z

297

International Standards in Forensic DNA  

E-Print Network [OSTI]

International Standards in Forensic DNA John M. Butler, Ph.D. National Institute of Standards and Technology NIST Fellow & Special Assistant to the Director for Forensic Science Vice-Chair, National Commission on Forensic Science World Forensics Festival Seoul, Korea October 15, 2014 #12;Definition

298

Amplification of chromosomal DNA in situ  

DOE Patents [OSTI]

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

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

2002-01-01T23:59:59.000Z

299

Damage identification and health monitoring of structural and mechanical systems from changes in their vibration characteristics: A literature review  

SciTech Connect (OSTI)

This report contains a review of the technical literature concerning the detection, location, and characterization of structural damage via techniques that examine changes in measured structural vibration response. The report first categorizes the methods according to required measured data and analysis technique. The analysis categories include changes in modal frequencies, changes in measured mode shapes (and their derivatives), and changes in measured flexibility coefficients. Methods that use property (stiffness, mass, damping) matrix updating, detection of nonlinear response, and damage detection via neural networks are also summarized. The applications of the various methods to different types of engineering problems are categorized by type of structure and are summarized. The types of structures include beams, trusses, plates, shells, bridges, offshore platforms, other large civil structures, aerospace structures, and composite structures. The report describes the development of the damage-identification methods and applications and summarizes the current state-of-the-art of the technology. The critical issues for future research in the area of damage identification are also discussed.

Doebling, S.W.; Farrar, C.R.; Prime, M.B.; Shevitz, D.W.

1996-05-01T23:59:59.000Z

300

How Damage Diversification Can Reduce Systemic Risk  

E-Print Network [OSTI]

We consider the problem of risk diversification in complex networks. Nodes represent e.g. financial actors, whereas weighted links represent e.g. financial obligations (credits/debts). Each node has a risk to fail because of losses resulting from defaulting neighbors, which may lead to large failure cascades. Classical risk diversification strategies usually neglect network effects and therefore suggest that risk can be reduced if possible losses (i.e., exposures) are split among many neighbors (exposure diversification, ED). But from a complex networks perspective diversification implies higher connectivity of the system as a whole which can also lead to increasing failure risk of a node. To cope with this, we propose a different strategy (damage diversification, DD), i.e. the diversification of losses that are imposed on neighboring nodes as opposed to losses incurred by the node itself. Here, we quantify the potential of DD to reduce systemic risk in comparison to ED. For this, we develop a branching proce...

Burkholz, Rebekka; Schweitzer, Frank

2015-01-01T23:59:59.000Z

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


301

Response Elements  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

The Guide provides acceptable methods for meeting the requirement of DOE O 151.1C for response elements that respond or contribute to response as needed in an emergency. Cancels DOE G 151.1-1, Volume 3-1, DOE G 151.1-1, Volume 3-2, DOE G 151.1-1, Volume 3-3, DOE G 151.1-1, Volume 3-4, DOE G 151.1-1, Volume 4-1, DOE G 151.1-1, Volume 4-2, DOE G 151.1-1, Volume 4-3, DOE G 151.1-1, Volume 4-4, DOE G 151.1-1, Volume 4-5, and DOE G 151.1-1, Volume 4-6.

2007-07-11T23:59:59.000Z

302

DNA nanotubes and helical nanotapes via self-assembly of ssDNA-amphiphiles  

E-Print Network [OSTI]

DNA nanotubes and helical nanotapes via self- assembly of ssDNA-amphiphiles Timothy R. Pearcea and Efrosini Kokkoli*b DNA nanotubes were created using molecular self-assembly of single-stranded DNA (ss. The nanotube structures were formed by bilayers of amphiphiles, with the hydrophobic components forming

Kokkoli, Efie

303

Supplementary Information for: Integrating DNA Strand Displacement Circuitry with DNA Tile Self-assembly  

E-Print Network [OSTI]

Supplementary Information for: Integrating DNA Strand Displacement Circuitry with DNA Tile Self-assembly of Contents: · Supplementary Figures 1. Native polyacrylamide gel electrophoresis of DNA tile self-assembly 2. UV absorbance annealing and melting curves of DNA tile self-assembly 3. Characterization

Zhang, David Yu

304

Single-Molecule Study of DNA Polymerization Activity of HIV-1 Reverse Transcriptase on DNA Templates  

E-Print Network [OSTI]

Single-Molecule Study of DNA Polymerization Activity of HIV-1 Reverse Transcriptase on DNA unwinding protein, such as a helicase. In order to understand the mechanism of polymerization through secondary structures, we investigated the DNA polymerization activity of HIV-1 RT on long ssDNA templates

Xie, Xiaoliang Sunney

305

Probe and method for DNA detection  

DOE Patents [OSTI]

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

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

2013-07-02T23:59:59.000Z

306

Self-assembled DNA Structures for Nanoconstruction  

E-Print Network [OSTI]

Self-assembled DNA Structures for Nanoconstruction Hao Yan, Peng Yin, Sung Ha Park, Hanying Li methods based on DNA self-assembly. Here we review our recent experimental progress to utilize novel DNA nanostructures for self-assembly as well as for templates in the fabrication of functional nano

Yin, Peng

307

HELICASE DEPENDENT AMPLICATION transfer the DNA  

E-Print Network [OSTI]

STEP 1 STEP 2 STEP 3 HELICASE DEPENDENT AMPLICATION HELICASE DNA POLYMERASE transfer the DNA instrumentation. MOLECULAR BIOMARKERS MADE UP DNA or RNA STRANDS ARE A POWERFUL WEAPON IN DETECTING DISEASE. USING for sample preparation at the point to care using only hand generated power.... #12;

308

Exploring the common molecular basis for the universal DNA mutation bias: Revival of Loewdin mutation model  

SciTech Connect (OSTI)

Highlights: {yields} There exists a universal G:C {yields} A:T mutation bias in three domains of life. {yields} This universal mutation bias has not been sufficiently explained. {yields} A DNA mutation model proposed by Loewdin 40 years ago offers a common explanation. -- Abstract: Recently, numerous genome analyses revealed the existence of a universal G:C {yields} A:T mutation bias in bacteria, fungi, plants and animals. To explore the molecular basis for this mutation bias, we examined the three well-known DNA mutation models, i.e., oxidative damage model, UV-radiation damage model and CpG hypermutation model. It was revealed that these models cannot provide a sufficient explanation to the universal mutation bias. Therefore, we resorted to a DNA mutation model proposed by Loewdin 40 years ago, which was based on inter-base double proton transfers (DPT). Since DPT is a fundamental and spontaneous chemical process and occurs much more frequently within GC pairs than AT pairs, Loewdin model offers a common explanation for the observed universal mutation bias and thus has broad biological implications.

Fu, Liang-Yu [National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China) [National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070 (China); Wang, Guang-Zhong [State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China)] [State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101 (China); Ma, Bin-Guang [Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070 (China)] [Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070 (China); Zhang, Hong-Yu, E-mail: zhy630@mail.hzau.edu.cn [National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China) [National Key Laboratory of Crop Genetic Improvement, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Center for Bioinformatics, Huazhong Agricultural University, Wuhan 430070 (China)

2011-06-10T23:59:59.000Z

309

Sm and DNA Binding by dual reactive B cells requires distinct V{sub H}, V{sub {kappa}}, and V{sub H} CDR3 structures  

SciTech Connect (OSTI)

We have previously demonstrated an overlap of the anti-Sm and anti-DNA responses in MRL/Mp-Ipr/Ipr mice. The Ab produced by many anti-Sm hybridomas bind DNA and are encoded by Ig V genes used by anti-DNA hybridomas. In addition, some anti-Sm Ab that bind DNA have acquired mutations that improve DNA binding, indicating that DNA is a selecting Ag in the anti-Sm response. To gain insight into the basis for the dual binding ability of these Ab, we coexpressed the H chain from the anti-Sm hybridoma 2-12 with nine different L chains. Hybridoma 2-12 binds Sm but not DNA, yet expresses the same J558 V{sub H} gene as three anti-Sm hybridomas that bind ssDNA and at least one anti-DNA hybridoma that does not bind Sm. We found that most of the transfectoma Ab bind Sm, but their avidities vary over more than 3 orders of magnitude. Five of the nine transfectoma Ab bind ssDNA, and none bind dsDNA. In general, the ability to bind each Ag follows the binding ability of the hybridoma from which the L chain is derived. H Chain swapping experiments indicate that the H chain, V{sub H} CDR3 in particular contributes to the binding of both Sm and DNA. We conclude that Sm and DNA select for distinct features of V{sub H}, V{sub {kappa}}, and V{sub H} CDR3, suggesting selection by both Ag in the anti-Sm response.

Retter, M.W.; Eisenberg, R.A.; Cohen, P.L. [Univ. of North Carolina, Chapel Hill, NC (United States)] [and others

1995-08-15T23:59:59.000Z

310

Precursors to potential severe core damage accidents: 1994, a status report. Volume 22: Appendix I  

SciTech Connect (OSTI)

Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 {times} 10{sup {minus}6}. These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1.

Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Vanden Heuvel, L.N. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); Dolan, B.W.; Minarick, J.W. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); [Science Applications International Corp., Oak Ridge, TN (United States)

1995-12-01T23:59:59.000Z

311

Binary electrokinetic separation of target DNA from background DNA primers.  

SciTech Connect (OSTI)

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

James, Conrad D.; Derzon, Mark Steven

2005-10-01T23:59:59.000Z

312

Flavin-Induced Oligomerization in Escherichia coli Adaptive Response Protein AidB  

E-Print Network [OSTI]

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

Drennan, Catherine L.

313

Fleet DNA Project (Fact Sheet)  

SciTech Connect (OSTI)

The Fleet DNA Project - designed by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in partnership with Oak Ridge National Laboratory - aims to accelerate the evolution of advanced vehicle development and support the strategic deployment of market-ready technologies that reduce costs, fuel consumption, and emissions. At the heart of the Fleet DNA Project is a clearinghouse of medium- and heavy-duty commercial fleet transportation data for optimizing the design of advanced vehicle technologies or for selecting a given technology to invest in. An easy-to-access online database will help vehicle manufacturers and fleets understand the broad operational range for many of today's commercial vehicle vocations.

Not Available

2012-10-01T23:59:59.000Z

314

Electromagnetic Signals from Bacterial DNA  

E-Print Network [OSTI]

Chemical reactions can be induced at a distance due to the propagation of electromagnetic signals during intermediate chemical stages. Although is is well known at optical frequencies, e.g. photosynthetic reactions, electromagnetic signals hold true for muck lower frequencies. In E. coli bacteria such electromagnetic signals can be generated by electric transitions between energy levels describing electrons moving around DNA loops. The electromagnetic signals between different bacteria within a community is a "wireless" version of intercellular communication found in bacterial communities connected by "nanowires". The wireless broadcasts can in principle be of both the AM and FM variety due to the magnetic flux periodicity in electron energy spectra in bacterial DNA orbital motions.

A. Widom; J. Swain; Y. N. Srivastava; S. Sivasubramanian

2012-02-09T23:59:59.000Z

315

Channel plate for DNA sequencing  

DOE Patents [OSTI]

This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface. 15 figs.

Douthart, R.J.; Crowell, S.L.

1998-01-13T23:59:59.000Z

316

Computational Hydrocode Study of Target Damage due to Fragment-Blast Impact  

SciTech Connect (OSTI)

A target's terminal ballistic effects involving explosively generated fragments, along with the original blast, are of critical importance for many different security and safety related applications. Personnel safety and protective building design are but a few of the practical disciplines that can gain from improved understanding combined loading effects. Traditionally, any engineering level analysis or design effort involving explosions would divide the target damage analysis into two correspondingly critical areas: blast wave and fragment related impact effects. The hypothesis of this paper lies in the supposition that a linear combination of a blast-fragment loading, coupled with an accurate target response description, can lead to a non-linear target damage effect. This non-linear target response could then stand as the basis of defining what a synergistic or combined frag-blast loading might actually look like. The table below, taken from Walters, et. al. categorizes some of the critical parameters driving any combined target damage effect and drives the evaluation of results. Based on table 1 it becomes clear that any combined frag-blast analysis would need to account for the target response matching similar ranges for the mechanics described above. Of interest are the critical times upon which a blast event or fragment impact loading occurs relative to the target's modal response. A blast, for the purposes of this paper is defined as the sudden release of chemical energy from a given material (henceforth referred to as an energetic material) onto its surrounding medium. During the coupling mechanism a discrete or discontinuous shockwave is generated. This shockwave travels outward from the source transferring energy and momentum to any surrounding objects including personnel and engineering structures. From an engineering perspective blast effects are typically characterized by way of physical characteristics such as Peak Pressure (PP), Time of Arrival (TOA), Pressure-Impulse (PI) and Time of Duration (TD). Other peculiarities include the radial decrease in pressure from the source, any fireball size measurement, and subsequent increase in temperature from the passing of the shockwave through the surrounding medium. In light of all of these metrics, the loading any object receives from a blast event becomes intricately connected to the distance between itself and the source. Because of this, a clear distinction is made between close-in effects and those from a source far away from the object of interest. Explosively generated fragments on the other hand are characterized by means of their localized damage potential. Metrics such as whether the fragment penetrates or perforates a given object is quantified as well as other variables including fragment's residual velocity, % kinetic energy decrease, residual fragment mass and other exit criteria. A fragment launched under such violent conditions could easily be traveling at speeds in excess of 2500 ft/s. Given these speeds it is conceivable to imagine how any given fragment could deliver a concentrated load to a target and penetrates through walls, vehicles or even the protection systems of nearby personnel. This study will focus on the individual fragment-target impact event with the hopes of expanding it to eventually include statistical procedures. Since this is a modeling excursion into the combined frag-blast target damage effects the numerical methods used to frame this problem become important in-so-far as the simulations are done in a consistent manner. For this study a Finite-Element based Hydrocode solution called ALE3D (ALE=Arbitrary Lagrangian-Eulerian) was utilized. ALE3D is developed by Lawrence Livermore National Laboratory (Livermore, CA), and as this paper will show, successfully implemented a converged ALE formulation including as many of the different aspects needed to query the synergistic damage on a given target. Further information on the modeling setup is included.

Hatch-Aguilar, T; Najjar, F; Szymanski, E

2011-03-24T23:59:59.000Z

317

Demand Response and Open Automated Demand Response  

E-Print Network [OSTI]

LBNL-3047E Demand Response and Open Automated Demand Response Opportunities for Data Centers G described in this report was coordinated by the Demand Response Research Center and funded by the California. Demand Response and Open Automated Demand Response Opportunities for Data Centers. California Energy

318

Introduction Organisms exhibit a heat shock response in which  

E-Print Network [OSTI]

Introduction Organisms exhibit a heat shock response in which increased expression of stress proteins (or heat shock proteins, HSPs) is coincident with the induction of thermotolerance (the ability tissue because heat shock (HS) can protect neurons against ischaemic damage1 and this protection may

Robertson, Meldrum

319

Strain localization and cyclic damage of polyurethane foam cylinders: experimental tests and theoretical model  

E-Print Network [OSTI]

Strain localization and cyclic damage of polyurethane foam cylinders: experimental tests subject to progressive damage. The chain of springs models the strain localization, and the second series qualitative agreement with the experiments. Keywords: polyurethane foams; strain localization; cyclic damage

Boyer, Edmond

320

ENVIRONMENTAL DAMAGE AS NEGATIVE EXTERNALITY: UNCERTAINTY, MORAL COMPLEXITY AND THE LIMITS OF THE MARKET  

E-Print Network [OSTI]

21 ENVIRONMENTAL DAMAGE AS NEGATIVE EXTERNALITY: UNCERTAINTY, MORAL COMPLEXITY AND THE LIMITS environmental damage with a sociological approach, I show how the process of externalities definition inclusive and democratic public deliberation on environmental damage and its reparation. Key Words

Boyer, Edmond

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


321

IH Report #04-010 April 2004 Water Damage Response (Mold Prevention)  

E-Print Network [OSTI]

small quantity, well contained and easily cleaned up within 24 hours, and building materials do not have) This document is designed to help facility zone and building managers take proper action when addressing, tub or sink overflows and rainwater, or Contaminated Water ­ contaminated with sewage, biological

322

Automated structural damage detection using one class machine learning  

E-Print Network [OSTI]

Measuring and analysing the vibration of structures using sensors can help identify and detect damage, potentially prolonging the life of structures and preventing disasters. Wireless sensor systems promise to make this ...

Long, James, S.M. Massachusetts Institute of Technology

2014-01-01T23:59:59.000Z

323

Neutron and gamma irradiation damage to organic materials.  

SciTech Connect (OSTI)

This document discusses open literature reports which investigate the damage effects of neutron and gamma irradiation on polymers and/or epoxies - damage refers to reduced physical chemical, and electrical properties. Based on the literature, correlations are made for an SNL developed epoxy (Epon 828-1031/DDS) with an expected total fast-neutron fluence of {approx}10{sup 12} n/cm{sup 2} and a {gamma} dosage of {approx}500 Gy received over {approx}30 years at < 200 C. In short, there are no gamma and neutron irradiation concerns for Epon 828-1031/DDS. To enhance the fidelity of our hypotheses, in regards to radiation damage, we propose future work consisting of simultaneous thermal/irradiation (neutron and gamma) experiments that will help elucidate any damage concerns at these specified environmental conditions.

White, Gregory Von, II; Bernstein, Robert

2012-04-01T23:59:59.000Z

324

RADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS  

E-Print Network [OSTI]

B. and Gupta, R. , “Radiation Resistant Magnets for the RIARADIATION DAMAGE TO BSCCO-2223 FROM 50 MEV PROTONS A. F.HTS materials in high radiation environments requires that

Zeller, A.F.; Ronningen, R.M.; Godeke, A.; Heilbronn, L.H.; McMahan-Norris, P.; Gupta, R.

2007-01-01T23:59:59.000Z

325

Review of Dynamic Recovery Effects on Ion Irradiation Damage...  

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

6H–SiC, ionization processes are less dominant. Citation: Weber WJ, Y Zhang, and LM Wang.2012."Review of Dynamic Recovery Effects on Ion Irradiation Damage in...

326

Obstacles to Determining Punitive Damages in Class Actions  

E-Print Network [OSTI]

Courts and commentators have often embraced the class action device as an ideal means of assessing punitive damages fairly in mass tort cases. In this Article, Professor Hines sounds a cautionary note by identifying a number of procedural...

Hines, Laura J.

2001-01-01T23:59:59.000Z

327

Assessing blackbird damage to ripening rice in Matagorda County, Texas  

E-Print Network [OSTI]

of pyrotechnic and auditory scare devices, but with only limited success. However, in order to develop new control techniques, as well as to test the efficacy of current techniques, damage must be accurately assessed. Large scale estimates (over entire fields...

Wright, Robert Glen

1987-01-01T23:59:59.000Z

328

Hail Ice Damage of Stringer-Stiffened Curved Composite Panels /  

E-Print Network [OSTI]

Damage. Composite Structures 2003;62:213–21. Ice Drop.How to make clear ice. 28 February 2011. Victoria, BC,2011/02/how-to- make-clear-ice-that-actually-works/ Graham,

Le, Jacqueline Linh

2013-01-01T23:59:59.000Z

329

Drag amplification and fatigue damage in vortex-induced vibrations  

E-Print Network [OSTI]

Fatigue damage and drag force amplification due to Vortex-Induced-Vibrations (VIV) continue to cause significant problems in the design of structures which operate in ocean current environments. These problems are magnified ...

Jhingran, Vikas Gopal

2008-01-01T23:59:59.000Z

330

Visual Indication of Mechanical Damage Using Core-Shell Microcapsules  

E-Print Network [OSTI]

-7 Changes in pH have been used to detect compression in polymer brushes,8 and microcapsules containing a p have been incorporated into filled hollow fibers to enhance damage visibility in the structure

Sottos, Nancy R.

331

Economic Damages from Climate Change: An Assessment of Market Impacts  

E-Print Network [OSTI]

damage induced by sea level rise in the United States. InImpacts on Water Sea Level Rise Temperature-Related Extremewater supply and sea level rise and the costs of adjustment

Hanemann, W Michael; Dale, Larry

2006-01-01T23:59:59.000Z

332

Effects of ballistic damage on the dynamics of composite driveshafts  

E-Print Network [OSTI]

The objective of this research program is to study the dynamics of a composite driveshaft before and after ballistic damage is incurred. Driveshafts are tested under static and dynamic loads to obtain material, mechanical, and vibrational...

Ayers, Thomas Ray

1993-01-01T23:59:59.000Z

333

Existence and Regularity for Dynamic Viscoelastic Adhesive Contact with Damage  

SciTech Connect (OSTI)

A model for the dynamic process of frictionless adhesive contact between a viscoelastic body and a reactive foundation, which takes into account the damage of the material resulting from tension or compression, is presented. Contact is described by the normal compliance condition. Material damage is modelled by the damage field, which measures the pointwise fractional decrease in the load-carrying capacity of the material, and its evolution is described by a differential inclusion. The model allows for different damage rates caused by tension or compression. The adhesion is modelled by the bonding field, which measures the fraction of active bonds on the contact surface. The existence of the unique weak solution is established using the theory of set-valued pseudomonotone operators introduced by Kuttler and Shillor (1999). Additional regularity of the solution is obtained when the problem data is more regular and satisfies appropriate compatibility conditions.

Kuttler, Kenneth L. [Department of Mathematics, Brigham Young University, Provo, UT 84602 (United States)], E-mail: klkuttler@math.byu.edu; Shillor, Meir [Department of Mathematics and Statistics, Oakland University, Rochester, MI 48309 (United States)], E-mail: shillor@oakland.edu; Fernandez, Jose R. [Departamento de Matematica Aplicada, Facultade de Matematicas, University of Santiago de Compostela, 15706 Santiago de Compostela (Spain)], E-mail: jramon@usc.es

2006-01-15T23:59:59.000Z

334

CONSULTATION RESPONSE Wellcome Trust response to Workforce  

E-Print Network [OSTI]

account of in workforce planning. The importance of integrating academic training with clinical trainingCONSULTATION RESPONSE Wellcome Trust response to Workforce of the Healthcare Science Workforce Modernising Scientific Careers: The Next Steps Response by the Wellcome Trust

Rambaut, Andrew

335

Architectural Accommodation in the Complex of Four p53 DNA Binding Domain Peptides with the p21/waf1/cip1  

E-Print Network [OSTI]

1/cip1 DNA Response Element* (Received for publication, January 10, 1997, and in revised form, March acids 98­ 309) and the p21/waf1/cip1 DNA response element impli- cated in the G1/S phase cell cycle, gadd45, and p21/waf1/cip1, the last being involved in the G1/S phase checkpoint (5­8). When ex- pressed

Clore, G. Marius

336

Quantitative studies of severe fuel damage using delayed neutron data  

SciTech Connect (OSTI)

A technique to quantify fuel damage in an LMR through analysis of delayed neutron data is presented, which is suitable for analysis of both small-scale in-pile experiments and full-scale plants. Validating analyses are described for five in-pile severe accident simulations performed within the SLSF and Mol 7C test programs. Comparison is made of measured and calculated amounts of fuel damage. 8 refs., 5 figs., 2 tabs.

Bauer, T.H.; Braid, T.H. (Argonne National Lab., IL (USA)); Schleisiek, K. (Kernforschungszentrum Karlsruhe GmbH (Germany, F.R.))

1990-01-01T23:59:59.000Z

337

Quantitative studies of severe fuel damage using delayed neutron data  

SciTech Connect (OSTI)

In this paper, a technique is presented to quantify fuel damage in a liquid-metal reactor through fast-running computer analysis of delayed neutron data, suitable for analysis of both small-scale in-pile experiments and full-scale plants. Validating analyses are described for five in-pile severe accident simulations performed within the Sodium Loop Safety Facility and Mol-7C test programs. Comparison is made of measured and calculated amounts of fuel damage.

Bauer, T.H.; Braiel, T.H. (Argonne National Lab., IL (United States)); Schleisiek, K. (Kernforschungszentrum Karlsruhe GmbH (Germany))

1992-09-01T23:59:59.000Z

338

The application of ultrasonics to assess damage in composite materials  

E-Print Network [OSTI]

THE APPLICATION OF ULTRASONICS TO ASSESS DAMAGE IN COMPOSITE MATERIALS A Thesis by JOHN GREGORY EDEN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... December 1985 Major Subjectr Aerospace Engineering THE APPLICATION OF ULTRASONICS TO ASSESS DAMAGE IN COMPOSITE MATERIALS A Thesis by JOHN GREGORY EDEN Approved as to style and content by: (V. . Kinra, Chairman) (D. H. Allen, Member) (R. A...

Eden, John Gregory

2012-06-07T23:59:59.000Z

339

Viscoelastic{Viscoplastic Damage Model for Asphalt Concrete  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.2.1 Yield surface . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2.2.2 Viscoplastic potential energy function . . . . . . . . . . . . . . 23 2.2.3 Hardening function . . . . . . . . . . . . . . . . . . . . . . . . 23 2.3 Numerical... viii LIST OF FIGURES FIGURE Page 1.1 Moisture-induced damage in pavements results in raveling and potholing 4 1.2 Adhesive and cohesive failure . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Damaged and e ective undamaged con gurations...

Graham, Michael A.

2010-10-12T23:59:59.000Z

340

Grey Squirrel bark stripping damage A Case Study  

E-Print Network [OSTI]

Height & DBH each tree Stems per ha Basal area Thinned Nov 1998 43% removed Growth Rate 1998 & 2003 with no damage 223 81.1 51 39 7 13/04/2010 #12;Case study DBH Tree size (DBH) v year of damage for `new.4 9.4 11.4 10 9 12 11 Basal area Post thinning 25.4 18.0 20.0 18 20 18 19 Total Basal area 27.2 28

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


341

Predicting threshold and location of laser damage on optical surfaces  

DOE Patents [OSTI]

An apparatus useful in the prediction of the damage threshold of various optical devices, the location of weak spots on such devices and the location, identification, and elimination of optical surface impurities comprising, a focused and pulsed laser, an photo electric detector/imaging means, and a timer. The weak spots emit photoelectrons when subjected to laser intensities that are less than the intensity actually required to produce the damage. The weak spots may be eliminated by sustained exposure to the laser beam.

Siekhaus, Wigbert (Berkeley, CA)

1987-01-01T23:59:59.000Z

342

Laser-induced Damage in Optical Materials: 2004  

SciTech Connect (OSTI)

This volume contains papers presented at the 35th Annual Symposium on Optical Materials for High-Power Lasers, held at the National Institute of Standards and Technology in Boulder, Colorado, 22-24 September 2003. The symposium was attended by 125 participants from China, India, Russia, France, Germany, Japan, the United States, and the United Kingdom. A meeting summary and some 75 reviewed papers appear. The book is divided into sections devoted to the following topics: thin films, surfaces and mirrors, fundamental mechanisms, materials and measurements, and finally, understanding optical damage with ultrashort laser pulses. Topics of interest to the high-peak-power and high-average-power laser communities in addition to damage issues related to various research efforts and commercial laser applications are discussed. Also discussed are improved scaling relations as a function of pulse duration in the femtosecond range, beam footprint size, and irradiation of optical materials with wavelengths down to the x-ray region. New sources at shorter wavelengths continue to be developed, and a corresponding shift in emphasis to short-wavelength and repetitively pulsed damage problems can be seen in some of these papers. Fabrication and test procedures are discussed particularly in the area of thin films. New materials and the implication of defects on the damage process are emphasized in addition to new reports of conditioning effects and damage repair or damage mitigation.

Exarhos, Gregory J.; Guenther, Arthur H.; Kaiser, Norbert; Lewis, Keith L.; Soileau, M. J.; Stolz, Christopher J.

2005-03-01T23:59:59.000Z

343

Femtosecond pulse damage thresholds of dielectric coatings in vacuum  

SciTech Connect (OSTI)

At 10-7 Torr, the multiple femtosecond pulse damage threshold, F(?), is about 10% of the single pulse damage fluence F(1) for hafnia and silica films compared to about 65% and 50%, respectively, at 630 Torr. In contrast, the single-pulse damage threshold is pressure independent. The decrease of F(?) with decreasing air pressure correlates with the water vapor and oxygen content of the ambient gas with the former having the greater effect. The decrease in F(?) is likely associated with an accumulation of defects derived from oxygen deficiency, for example vacancies. From atmospheric air pressure to pressures of {approx}3 x 10{sup -6} Torr, the damage 'crater' starts deterministically at the center of the beam and grows in diameter as the fluence increases. At pressure below 3x10-6 Torr, damage is initiated at random 'sites' within the exposed area in hafnia films, while the damage morphology remains deterministic in silica films. A possible explanation is that absorbing centers are created at predisposed sample sites in hafnia, for example at boundaries between crystallites, or crystalline and amorphous phases.

Michelle D. Shinn, Duy N. Nguyen, Luke A. Emmert ,Paul Schwoebel, Dinesh Patel, Carmen S. Menoni, Wolfgang Rudolph

2011-03-01T23:59:59.000Z

344

acetaminophen-induced oxidative damage: Topics by E-print Network  

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

and damage detection...21 3.5 Damage identification using a 3DOFs reduced order system Yang, Jann 105 Numerical aperture...

345

E-Print Network 3.0 - adapted damage control Sample Search Results  

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

Carlo simulation Summary: : Monte Carlo simulation; Masked irradiation damage; Josephson junction 1. Introduction Controlled... controlled damaged barrier layers, due to the long...

346

Reliability-based framework for fatigue damage prognosis of bonded structural elements in aerospace composite structures  

E-Print Network [OSTI]

situ damage detection of composite materials for structuralmaterials, Journal of Composite Materials , 10, 342-354,effects in damaged composite aerospace structures ,

Gobbato, Maurizio

2011-01-01T23:59:59.000Z

347

DNA  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation Proposed Newcatalyst phases onOrganization FY Middle SchoolARM-TR-01468This4t c 5DMSEdrives

348

Enhancing the DNA Patent Database  

SciTech Connect (OSTI)

Final Report on Award No. DE-FG0201ER63171 Principal Investigator: LeRoy B. Walters February 18, 2008 This project successfully completed its goal of surveying and reporting on the DNA patenting and licensing policies at 30 major U.S. academic institutions. The report of survey results was published in the January 2006 issue of Nature Biotechnology under the title “The Licensing of DNA Patents by US Academic Institutions: An Empirical Survey.” Lori Pressman was the lead author on this feature article. A PDF reprint of the article will be submitted to our Program Officer under separate cover. The project team has continued to update the DNA Patent Database on a weekly basis since the conclusion of the project. The database can be accessed at dnapatents.georgetown.edu. This database provides a valuable research tool for academic researchers, policymakers, and citizens. A report entitled Reaping the Benefits of Genomic and Proteomic Research: Intellectual Property Rights, Innovation, and Public Health was published in 2006 by the Committee on Intellectual Property Rights in Genomic and Protein Research and Innovation, Board on Science, Technology, and Economic Policy at the National Academies. The report was edited by Stephen A. Merrill and Anne-Marie Mazza. This report employed and then adapted the methodology developed by our research project and quoted our findings at several points. (The full report can be viewed online at the following URL: http://www.nap.edu/openbook.php?record_id=11487&page=R1). My colleagues and I are grateful for the research support of the ELSI program at the U.S. Department of Energy.

Walters, LeRoy B.

2008-02-18T23:59:59.000Z

349

On Damage Propagation in a Soft Low-Permeability Formation  

SciTech Connect (OSTI)

In this presentation, we develop a mathematical model of fluid flow with changing formation properties. The modification of formation permeability is caused by development of a connected system of fractures. As the fluids are injected or withdrawn from the reservoir, the balance between the pore pressure and the geostatic formation stresses is destroyed. If the strength of the rock is not sufficient to accommodate such an imbalance, the cementing bonds between the rock grains become broken. Such a process is called damage propagation. The micromechanics and the basic mathematical model of damage propagation have been studied in [7]. The theory was further developed in [3], where new nonlocal damage propagation model has been studied. In [2] this theory has been enhanced by incorporation of the coupling between damage propagation and fluid flow. As it has been described above, the forced fluid flow causes changes in the rock properties including formation permeability. At the same time, changing permeability facilitates fluid flow and, therefore, enhances damage propagation. One of the principle concepts introduced in [3] and [2] is the characterization of damage by a dimensionless ratio of the number of broken bonds to the number of bonds in pristine rock per unit volume. It turns out, that the resulting mathematical model consist of a system of two nonlinear parabolic equations. As it has been shown in [6] using modeling of micromechanical properties of sedimentary rocks, at increasing stress the broken bonds coalesce into a system of cracks surrounding practically intact matrix blocks. These blocks have some characteristic size and a regular geometry. The initial microcracks expand, interact with each other, coalesce and form bigger fractures, etc. Therefore, as the damage is accumulated, the growing system of connected fractures determines the permeability of the reservoir rock. Significant oil deposits are stored in low-permeability soft rock reservoirs such as shales, chalks and diatomites [9, 10]. The permeability of the pristine formation matrix in such reservoirs is so low that oil production was impossible until hydraulic fracturing was applied. For development of correct production policy, it is very significant to adequately understand and predict how fast and to what extend the initial damage induced by drilling and hydrofracturing will propagate into the reservoir. The importance of fractures for rock flow properties is a well-established and recognized fact [4, 9, 5]. Different conceptual models have been developed [8]. In this study, we propose a damage propagation model based on a combination of the model of double-porosity and double-permeability medium [4] and a modification of the model of damage propagation developed in [2].

Silin, D.; Patzek, T.; Barenblatt, G.I.

2003-11-18T23:59:59.000Z

350

DNA-guided nanoparticle assemblies  

DOE Patents [OSTI]

In some embodiments, DNA-capped nanoparticles are used to define a degree of crystalline order in assemblies thereof. In some embodiments, thermodynamically reversible and stable body-centered cubic (bcc) structures, with particles occupying <.about.10% of the unit cell, are formed. Designs and pathways amenable to the crystallization of particle assemblies are identified. In some embodiments, a plasmonic crystal is provided. In some aspects, a method for controlling the properties of particle assemblages is provided. In some embodiments a catalyst is formed from nanoparticles linked by nucleic acid sequences and forming an open crystal structure with catalytically active agents attached to the crystal on its surface or in interstices.

Gang, Oleg; Nykypanchuk, Dmytro; Maye, Mathew; van der Lelie, Daniel

2013-07-16T23:59:59.000Z

351

Human Genome Research: Decoding DNA  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: Vegetation ProposedUsingFun withconfinement plasmas inPortalAllBPA addressesHowHughHumanDecoding DNA

352

Assembling semiconductor nanocomposites using DNA replication technologies.  

SciTech Connect (OSTI)

Deoxyribonucleic acid (DNA) molecules represent Nature's genetic database, encoding the information necessary for all cellular processes. From a materials engineering perspective, DNA represents a nanoscale scaffold with highly refined structure, stability across a wide range of environmental conditions, and the ability to interact with a range of biomolecules. The ability to mass-manufacture functionalized DNA strands with Angstrom-level resolution through DNA replication technology, however, has not been explored. The long-term goal of the work presented in this report is focused on exploiting DNA and in vitro DNA replication processes to mass-manufacture nanocomposite materials. The specific objectives of this project were to: (1) develop methods for replicating DNA strands that incorporate nucleotides with ''chemical handles'', and (2) demonstrate attachment of nanocrystal quantum dots (nQDs) to functionalized DNA strands. Polymerase chain reaction (PCR) and primer extension methodologies were used to successfully synthesize amine-, thiol-, and biotin-functionalized DNA molecules. Significant variability in the efficiency of modified nucleotide incorporation was observed, and attributed to the intrinsic properties of the modified nucleotides. Noncovalent attachment of streptavidin-coated nQDs to biotin-modified DNA synthesized using the primer extension method was observed by epifluorescence microscopy. Data regarding covalent attachment of nQDs to amine- and thiol-functionalized DNA was generally inconclusive; alternative characterization tools are necessary to fully evaluate these attachment methods. Full realization of this technology may facilitate new approaches to manufacturing materials at the nanoscale. In addition, composite nQD-DNA materials may serve as novel recognition elements in sensor devices, or be used as diagnostic tools for forensic analyses. This report summarizes the results obtained over the course of this 1-year project.

Heimer, Brandon W.; Crown, Kevin K.; Bachand, George David

2005-11-01T23:59:59.000Z

353

Optical Recognition of Converted DNA Nucleotides for Single-Molecule DNA  

E-Print Network [OSTI]

Optical Recognition of Converted DNA Nucleotides for Single-Molecule DNA Sequencing Using Nanopore among individual nucleotides (nt). The system must be capable of differentiating among the four bases

354

Structural Health Monitoring for Impact Damage in Composite Structures.  

SciTech Connect (OSTI)

Composite structures are increasing in prevalence throughout the aerospace, wind, defense, and transportation industries, but the many advantages of these materials come with unique challenges, particularly in inspecting and repairing these structures. Because composites of- ten undergo sub-surface damage mechanisms which compromise the structure without a clear visual indication, inspection of these components is critical to safely deploying composite re- placements to traditionally metallic structures. Impact damage to composites presents one of the most signi fi cant challenges because the area which is vulnerable to impact damage is generally large and sometimes very dif fi cult to access. This work seeks to further evolve iden- ti fi cation technology by developing a system which can detect the impact load location and magnitude in real time, while giving an assessment of the con fi dence in that estimate. Fur- thermore, we identify ways by which impact damage could be more effectively identi fi ed by leveraging impact load identi fi cation information to better characterize damage. The impact load identi fi cation algorithm was applied to a commercial scale wind turbine blade, and results show the capability to detect impact magnitude and location using a single accelerometer, re- gardless of sensor location. A technique for better evaluating the uncertainty of the impact estimates was developed by quantifying how well the impact force estimate meets the assump- tions underlying the force estimation technique. This uncertainty quanti fi cation technique was found to reduce the 95% con fi dence interval by more than a factor of two for impact force estimates showing the least uncertainty, and widening the 95% con fi dence interval by a fac- tor of two for the most uncertain force estimates, avoiding the possibility of understating the uncertainty associated with these estimates. Linear vibration based damage detection tech- niques were investigated in the context of structural stiffness reductions and impact damage. A method by which the sensitivity to damage could be increased for simple structures was presented, and the challenges of applying that technique to a more complex structure were identi fi ed. The structural dynamic changes in a weak adhesive bond were investigated, and the results showed promise for identifying weak bonds that show little or no static reduction in stiffness. To address these challenges in identifying highly localized impact damage, the possi- bility of detecting damage through nonlinear dynamic characteristics was also identi fi ed, with a proposed technique which would leverage impact location estimates to enable the detection of impact damage. This nonlinear damage identi fi cation concept was evaluated on a composite panel with a substructure disbond, and the results showed that the nonlinear dynamics at the damage site could be observed without a baseline healthy reference. By further developing impact load identi fi cation technology and combining load and damage estimation techniques into an integrated solution, the challenges associated with impact detection in composite struc- tures can be effectively solved, thereby reducing costs, improving safety, and enhancing the operational readiness and availability of high value assets.

Roach, Dennis P.; Raymond Bond (Purdue); Doug Adams (Purdue)

2014-08-01T23:59:59.000Z

355

INVOLVED IN DE NOVO 2-containing complex involved in RNA-directed DNA methylation in Arabidopsis  

SciTech Connect (OSTI)

At least three pathways control maintenance of DNA cytosine methylation in Arabidopsis thaliana. However, the RNA-directed DNA methylation (RdDM) pathway is solely responsible for establishment of this silencing mark. We previously described INVOLVED IN DE NOVO 2 (IDN2) as being an RNA-binding RdDM component that is required for DNA methylation establishment. In this study, we describe the discovery of two partially redundant proteins that are paralogous to IDN2 and that form a stable complex with IDN2 in vivo. Null mutations in both genes, termed IDN2-LIKE 1 and IDN2-LIKE 2 (IDNL1 and IDNL2), result in a phenotype that mirrors, but does not further enhance, the idn2 mutant phenotype. Genetic analysis suggests that this complex acts in a step in the downstream portion of the RdDM pathway. We also have performed structural analysis showing that the IDN2 XS domain adopts an RNA recognition motif (RRM) fold. Finally, genome-wide DNA methylation and expression analysis confirms the placement of the IDN proteins in an RdDM pathway that affects DNA methylation and transcriptional control at many sites in the genome. Results from this study identify and describe two unique components of the RdDM machinery, adding to our understanding of DNA methylation control in the Arabidopsis genome.

Ausin, Israel; Greenberg, Maxim V.C.; Simanshu, Dhirendra K.; Hale, Christopher J.; Vashisht, Ajay A.; Simon, Stacey A.; Lee, Tzuu-fen; Feng, Suhua; Española, Sophia D.; Meyers, Blake C.; Wohlschlegel, James A.; Patel, Dinshaw J.; Jacobsen, Steven E. (UCLA); (MSKCC); (Delaware)

2012-10-23T23:59:59.000Z

356

Assessment of substrate-stabilizing factors for DnaK on the folding of aggregation-prone proteins  

SciTech Connect (OSTI)

Hydrophobic interactions between molecular chaperones and their nonnative substrates have been believed to be mainly responsible for both substrate recognition and stabilization against aggregation. However, the hydrophobic contact area between DnaK and its substrate proteins is very limited and other factors of DnaK for the substrate stabilization could not be excluded. Here, we covalently fused DnaK to the N-termini of aggregation-prone proteins in vivo. In the context of a fusion protein, DnaK has the ability to efficiently solubilize its linked proteins. The point mutation of the residue of DnaK critical for the substrate recognition and the deletion of the C-terminal substrate-binding domain did not have significant effect on the solubilizing ability of DnaK. The results imply that other factors of DnaK, distinct from the hydrophobic shielding of folding intermediates, also contributes to stabilization of its noncovalently bound substrates against aggregation. Elucidation of the nature of these factors would further enhance our understanding of the substrate stabilization of DnaK for expedited protein folding.

Ryu, Kisun; Kim, Chul Woo; Kim, Byung Hee [Department of Biotechnology, College of Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Han, Kyoung Sim [Protheon Incorporated, Yonsei Engineering Research Center B120E, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Kim, Kyun-Hwan [Department of Pharmacology, School of Medicine, and Center for Diagnostic Medicine, Institute of Biomedical Science and Technology, Konkuk University, Seoul 143-701 (Korea, Republic of); Choi, Seong Il [Department of Biotechnology, College of Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Institute of Life Science and Biotechnology, Yonsei University, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of)], E-mail: seongilchoi@daum.net; Seong, Baik L. [Department of Biotechnology, College of Engineering, Yonsei University, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Protheon Incorporated, Yonsei Engineering Research Center B120E, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Institute of Life Science and Biotechnology, Yonsei University, 134 Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of)], E-mail: blseong@yonsei.ac.kr

2008-08-15T23:59:59.000Z

357

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

E-Print Network [OSTI]

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

Marchetti, Francesco

2009-01-01T23:59:59.000Z

358

Integrated Molecular Analysis Indicates Undetectable Change in DNA Damage in Mice after Continuous Irradiation at ~ 400-fold Natural Background Radiation  

E-Print Network [OSTI]

Background: In the event of a nuclear accident, people are exposed to elevated levels of continuous low dose-rate radiation. Nevertheless, most of the literature describes the biological effects of acute radiation.

Olipitz, Werner

359

Insulin signaling, dietary restriction and DNA damage : multiple roles for smk-1 in the mediation of C. elegans life span  

E-Print Network [OSTI]

6, 280-293. Schwartz, E.I. , Smilenov, L.B. , Price, M.A. ,Cardozo-Pelaez, F. , Smilenov, L. , Chan, S.L. , Chrest,

Wolff, Suzanne Christine

2008-01-01T23:59:59.000Z

360

A DNA Based Implementation of an Evolutionary Search for Good Encodings for DNA Computation  

E-Print Network [OSTI]

lelism, capacity, and power. This potential, however, is limited by the constraints imposed by the DNA chemistry 1]. Adleman 2] introduced a way to solve combina- torial optimization problems with DNA- mental reaction in DNA based computation is hydro- gen bonding between Watson-Crick complement base pairs

Deaton, Russell J.

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


361

Mechanisms for microvascular damage induced by ultrasound-activated microbubbles  

SciTech Connect (OSTI)

To provide insight into the mechanisms of microvascular damage induced by ultrasound-activated microbubbles, experimental studies were performed to correlate microvascular damage to the dynamics of bubble-vessel interactions. High-speed photomicrography was used to record single microbubbles interacting with microvessels in ex vivo tissue, under the exposure of short ultrasound pulses with a center frequency of 1 MHz and peak negative pressures (PNP) ranging from 0.8-4 MPa. Vascular damage associated with observed bubble-vessel interactions was either indicated directly by microbubble extravasation or examined by transmission electron microscopy (TEM) analyses. As observed previously, the high-speed images revealed that ultrasound-activated microbubbles could cause distention and invagination of adjacent vessel walls, and could form liquid jets in microvessels. Vessel distention, invagination, and liquid jets were associated with the damage of microvessels whose diameters were smaller than those of maximally expanded microbubbles. However, vessel invagination appeared to be the dominant mechanism for the damage of relative large microvessels.

Chen Hong; Brayman, Andrew A.; Evan, Andrew P.; Matula, Thomas J. [Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA (United States); Department of Anatomy and Cell Biology and Medicine, Indiana University School of Medicine, Indianapolis (United States); Center for Industrial and Medical Ultrasound, Applied Physics Laboratory, University of Washington, Seattle, WA (United States)

2012-10-03T23:59:59.000Z

362

b) Economic i) Total damage estimates: From Pimentel et al. (2000)  

E-Print Network [OSTI]

4) Impacts b) Economic i) Total damage estimates: From Pimentel et al. (2000) · United States #12;4) Impacts b) Economic i) Total damage estimates: From Pimentel et al. (2000) · United States Economic impacts from losses/damage #12;4) Impacts b) Economic i) Total damage estimates: From Pimentel et al

Nowak, Robert S.

363

Assessing Vulnerabilities, Risks, and Consequences of Damage to Critical Infrastructure  

SciTech Connect (OSTI)

Since the publication of 'Critical Foundations: Protecting America's Infrastructure,' there has been a keen understanding of the complexity, interdependencies, and shared responsibility required to protect the nation's most critical assets that are essential to our way of life. The original 5 sectors defined in 1997 have grown to 18 Critical Infrastructures and Key Resources (CIKR), which are discussed in the 2009 National Infrastructure Protection Plan (NIPP) and its supporting sector-specific plans. The NIPP provides the structure for a national program dedicated to enhanced protection and resiliency of the nation's infrastructure. Lawrence Livermore National Laboratory (LLNL) provides in-depth, multi-disciplinary assessments of threat, vulnerability, and consequence across all 18 sectors at scales ranging from specific facilities to infrastructures spanning multi-state regions, such as the Oil and Natural Gas (ONG) sector. Like many of the CIKR sectors, the ONG sector is comprised of production, processing, distribution, and storage of highly valuable and potentially dangerous commodities. Furthermore, there are significant interdependencies with other sectors, including transportation, communication, finance, and government. Understanding the potentially devastating consequences and collateral damage resulting from a terrorist attack or natural event is an important element of LLNL's infrastructure security programs. Our work began in the energy sector in the late 1990s and quickly expanded other critical infrastructure sectors. We have performed over 600 physical assessments with a particular emphasis on those sectors that utilize, store, or ship potentially hazardous materials and for whom cyber security is important. The success of our approach is based on building awareness of vulnerabilities and risks and working directly with industry partners to collectively advance infrastructure protection. This approach consists of three phases: The Pre-Assessment Phase brings together infrastructure owners and operators to identify critical assets and help the team create a structured information request. During this phase, we gain information about the critical assets from those who are most familiar with operations and interdependencies, making the time we spend on the ground conducting the assessment much more productive and enabling the team to make actionable recommendations. The Assessment Phase analyzes 10 areas: Threat environment, cyber architecture, cyber penetration, physical security, physical penetration, operations security, policies and procedures, interdependencies, consequence analysis, and risk characterization. Each of these individual tasks uses direct and indirect data collection, site inspections, and structured and facilitated workshops to gather data. Because of the importance of understanding the cyber threat, LLNL has built both fixed and mobile cyber penetration, wireless penetration and supporting tools that can be tailored to fit customer needs. The Post-Assessment Phase brings vulnerability and risk assessments to the customer in a format that facilitates implementation of mitigation options. Often the assessment findings and recommendations are briefed and discussed with several levels of management and, if appropriate, across jurisdictional boundaries. The end result is enhanced awareness and informed protective measures. Over the last 15 years, we have continued to refine our methodology and capture lessons learned and best practices. The resulting risk and decision framework thus takes into consideration real-world constraints, including regulatory, operational, and economic realities. In addition to 'on the ground' assessments focused on mitigating vulnerabilities, we have integrated our computational and atmospheric dispersion capability with easy-to-use geo-referenced visualization tools to support emergency planning and response operations. LLNL is home to the National Atmospheric Release Advisory Center (NARAC) and the Interagency Modeling and Atmospheric Assessment Center (IMAAC). NA

Suski, N; Wuest, C

2011-02-04T23:59:59.000Z

364

Dynamics and control of DNA sequence amplification  

SciTech Connect (OSTI)

DNA amplification is the process of replication of a specified DNA sequence in vitro through time-dependent manipulation of its external environment. A theoretical framework for determination of the optimal dynamic operating conditions of DNA amplification reactions, for any specified amplification objective, is presented based on first-principles biophysical modeling and control theory. Amplification of DNA is formulated as a problem in control theory with optimal solutions that can differ considerably from strategies typically used in practice. Using the Polymerase Chain Reaction as an example, sequence-dependent biophysical models for DNA amplification are cast as control systems, wherein the dynamics of the reaction are controlled by a manipulated input variable. Using these control systems, we demonstrate that there exists an optimal temperature cycling strategy for geometric amplification of any DNA sequence and formulate optimal control problems that can be used to derive the optimal temperature profile. Strategies for the optimal synthesis of the DNA amplification control trajectory are proposed. Analogous methods can be used to formulate control problems for more advanced amplification objectives corresponding to the design of new types of DNA amplification reactions.

Marimuthu, Karthikeyan [Department of Chemical Engineering and Center for Advanced Process Decision-Making, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Chakrabarti, Raj, E-mail: raj@pmc-group.com, E-mail: rajc@andrew.cmu.edu [Department of Chemical Engineering and Center for Advanced Process Decision-Making, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Division of Fundamental Research, PMC Advanced Technology, Mount Laurel, New Jersey 08054 (United States)

2014-10-28T23:59:59.000Z

365

DNA Motif Representation with Nucleotide Dependency  

E-Print Network [OSTI]

DNA Motif Representation with Nucleotide Dependency Francis Chin1 and Henry Leung1 1 Department, these representations cannot model biological binding sites well because they fail to capture nucleotide interdependence. It has been pointed out by many researchers that the nucleotides of the DNA binding site cannot

Chin, Francis Y.L.

366

Carbon Nanotube DNA Sensor and Sensing Mechanism  

E-Print Network [OSTI]

Carbon Nanotube DNA Sensor and Sensing Mechanism Xiaowu Tang,*,, Sarunya Bansaruntip, Nozomi; Revised Manuscript Received June 7, 2006 ABSTRACT We report the fabrication of single-walled carbon nanotube (SWNT) DNA sensors and the sensing mechanism. The simple and generic protocol for label

Le Roy, Robert J.

367

Recombinant DNA encoding a desulfurization biocatalyst  

DOE Patents [OSTI]

This invention relates to a recombinant DNA molecule containing a gene or genes which encode a biocatalyst capable of desulfurizing a fossil fuel which contains organic sulfur molecules. For example, the present invention encompasses a recombinant DNA molecule containing a gene or genes of a strain of Rhodococcus rhodochrous. 13 figs.

Rambosek, J.; Piddington, C.S.; Kovacevich, B.R.; Young, K.D.; Denome, S.A.

1994-10-18T23:59:59.000Z

368

High-energy radiation damage in zirconia: modeling results  

SciTech Connect (OSTI)

Zirconia is viewed as a material of exceptional resistance to amorphization by radiation damage, and consequently proposed as a candidate to immobilize nuclear waste and serve as an inert nuclear fuel matrix. Here, we perform molecular dynamics simulations of radiation damage in zirconia in the range of 0.1-0.5 MeV energies with account of electronic energy losses. We nd that the lack of amorphizability co-exists with a large number of point defects and their clusters. These, importantly, are largely isolated from each other and therefore represent a dilute damage that does not result in the loss of long-range structural coherence and amorphization. We document the nature of these defects in detail, including their sizes, distribution and morphology, and discuss practical implications of using zirconia in intense radiation environments.

Zarkadoula, Evangelia [Queen Mary, University of London] [Queen Mary, University of London; Devanathan, Ram [Pacific Northwest National Laboratory (PNNL)] [Pacific Northwest National Laboratory (PNNL); Weber, William J [ORNL] [ORNL; Seaton, M [Daresbury Laboratory, UK] [Daresbury Laboratory, UK; Todorov, I T [Daresbury Laboratory, UK] [Daresbury Laboratory, UK; Nordlund, Kai [University of Helsinki] [University of Helsinki; Dove, Martin T [Queen Mary, University of London] [Queen Mary, University of London; Trachenko, Kostya [Queen Mary, University of London] [Queen Mary, University of London

2014-01-01T23:59:59.000Z

369

Application Of Shakedown Analysis To Cyclic Creep Damage Limits  

SciTech Connect (OSTI)

Shakedown analysis may be used to provide a conservative estimate of local rupture and hence cyclic creep damage for use in a creep-fatigue assessment. The shakedown analysis is based on an elastic-perfectly plastic material with a temperature-dependent pseudo yield stress defined to guarantee that a shakedown solution exists which does not exceed rupture stress and temperature for a defined life. The ratio of design life to the estimated maximum cyclic life is the shakedown creep damage. The methodology does not require stress classification and is also applicable to cycles over the full range of temperature above and below the creep regime. Full cyclic creep and damage analysis is the alternative when shakedown analysis appears to be excessively conservative.

Carter, Peter [Stress Engineering Services Inc.] [Stress Engineering Services Inc.; Jetter, Robert I [Consultant] [Consultant; Sham, Sam [ORNL] [ORNL

2012-01-01T23:59:59.000Z

370

Electric DNA chips for determination of pathogenic microorganisms  

E-Print Network [OSTI]

Electric DNA chips for determination of pathogenic microorganisms Yanling Liu Doctoral thesis Liu (2008): Electric DNA chips for determination of pathogenic microorganisms. School of Biotechnology, Royal Institute of Technology (KTH), Stockholm, Sweden Abstract Silicon-based electric DNA chip arrays

Enfors, Sven-Olof

371

Mitochondrial DNA phylogenetic analysis of Myrmecolacidae (Insecta: Strepsiptera) va  

E-Print Network [OSTI]

Guinea are determined. Methods were developed for extraction, amplification, and sequencing of mitochondrial DNA (mtDNA) from Strepsiptera. High-resolution mtDNA sequences obtained by these methods were used in the phylogenetic analysis of Myrmecolacidae...

Halbert, Natalie Rose

2013-02-22T23:59:59.000Z

372

Single molecule analysis of DNA electrophoresis in microdevices  

E-Print Network [OSTI]

Given that current electrophoresis technology is inadequate for mapping large O[100 kilobasepair] DNA, several promising lab-on-chip designs for DNA mapping have been recently proposed that require either 1) a DNA molecule ...

Randall, Greg C

2006-01-01T23:59:59.000Z

373

Thermal annealing of laser damage precursors on fused silica surfaces  

SciTech Connect (OSTI)

Previous studies have identified two significant precursors of laser damage on fused silica surfaces at fluenes below {approx} 35 J/cm{sup 2}, photoactive impurities in the polishing layer and surface fractures. In the present work, isothermal heating is studied as a means of remediating the highly absorptive, defect structure associated with surface fractures. A series of Vickers indentations were applied to silica surfaces at loads between 0.5N and 10N creating fracture networks between {approx} 10{micro}m and {approx} 50{micro}m in diameter. The indentations were characterized prior to and following thermal annealing under various times and temperature conditions using confocal time-resolved photo-luminescence (CTP) imaging, and R/1 optical damage testing with 3ns, 355nm laser pulses. Significant improvements in the damage thresholds, together with corresponding reductions in CTP intensity, were observed at temperatures well below the glass transition temperature (T{sub g}). For example, the damage threshold on 05.N indentations which typically initiates at fluences <8 J/cm{sup 2} could be improved >35 J/cm{sup 2} through the use of a {approx} 750 C thermal treatment. Larger fracture networks required longer or higher temperature treatment to achieve similar results. At an annealing temperature > 1100 C, optical microscopy indicates morphological changes in some of the fracture structure of indentations, although remnants of the original fracture and significant deformation was still observed after thermal annealing. This study demonstrates the potential of using isothermal annealing as a means of improving the laser damage resistance of fused silica optical components. Similarly, it provides a means of further understanding the physics associated with optical damage and related mitigation processes.

Shen, N; Miller, P E; Bude, J D; Laurence, T A; Suratwala, T I; Steele, W A; Feit, M D; Wang, L L

2012-03-19T23:59:59.000Z

374

Flow cytometric detection method for DNA samples  

DOE Patents [OSTI]

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM.TM. on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA.TM., on the 5' end.

Nasarabadi,Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Round Rock, TX)

2011-07-05T23:59:59.000Z

375

Atomic force microscopy of biochemically tagged DNA  

SciTech Connect (OSTI)

Small fragments of DNA of known length were made with the polymerase chain reaction. These fragments had biotin molecules covalently attached at their ends. They were subsequently labeled with a chimeric protein fusion between streptavidin and two immunoglobulin G-binding domains of staphyloccocal protein A. This tetrameric species was expected to bind up to four DNA molecules via their attached biotin moieties. The DNA-protein complex was deposited on mica and imaged with an atomic force microscope. The images revealed the protein chimera at the expected location at the ends of the strands of DNA as well as the expected dimers, trimers, and tetramers of DNA bound to a single protein. 25 refs., 5 figs.

Ogletree, D.F.; Kolbe, W.; Spengler, S.; Salmeron, M. (Lawrence Berkeley Laboratory, CA (United States)); Hansma, H.G.; Bezanilla, M. (Univ. of California, Santa Barbara (United States)); Sano, T.; Smith, C.S.; Cantor, C.R. (Boston Univ., MA (United States))

1993-05-01T23:59:59.000Z

376

Storing data encoded DNA in living organisms  

DOE Patents [OSTI]

Current technologies allow the generation of artificial DNA molecules and/or the ability to alter the DNA sequences of existing DNA molecules. With a careful coding scheme and arrangement, it is possible to encode important information as an artificial DNA strand and store it in a living host safely and permanently. This inventive technology can be used to identify origins and protect R&D investments. It can also be used in environmental research to track generations of organisms and observe the ecological impact of pollutants. Today, there are microorganisms that can survive under extreme conditions. As well, it is advantageous to consider multicellular organisms as hosts for stored information. These living organisms can provide as memory housing and protection for stored data or information. The present invention provides well for data storage in a living organism wherein at least one DNA sequence is encoded to represent data and incorporated into a living organism.

Wong; Pak C. (Richland, WA), Wong; Kwong K. (Sugar Land, TX), Foote; Harlan P. (Richland, WA)

2006-06-06T23:59:59.000Z

377

Flow cytometric detection method for DNA samples  

DOE Patents [OSTI]

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM, on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA, on the 5' end.

Nasarabadi, Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Livermore, CA)

2006-08-01T23:59:59.000Z

378

Analysis of tank damage during the 1994 Northridge earthquake  

SciTech Connect (OSTI)

The damage sustained by cylindrical liquid storage tanks during the 1994 Northridge earthquake is summarized. It included elephant foot buckling, anchor failure and roof-shell connection separation. A few of the important lessons learned, in particular, as related to the accuracy of code computations in predicting the actual behavior of these structures are outlined. A detailed case study is presented to illustrate the application of current seismic design standards to a damaged unanchored tank and to demonstrate the use of a state-of-the-art finite element analysis in assessing the seismic safety of the same tank.

Haroun, M.A.; Bhatia, H. [Univ. of California, Irvine, CA (United States). Dept. of Civil and Environmental Engineering

1995-12-31T23:59:59.000Z

379

Optical Damage Threshold of Silicon for Ultrafast Infrared Pulses  

SciTech Connect (OSTI)

While silicon has several properties making it an attractive material for structure-based laser-driven acceleration, its optical damage threshold, a key parameter for high-gradient acceleration, has been unknown. Here we present measurements of the optical damage threshold of crystalline silicon for ultrafast pulses in the mid-infrared. The wavelengths tested span a range from the telecommunications band at 1550 nm extending longer toward the two-photon absorption threshold at around 2200 nm. We discuss the prevailing theories of ultrafast optical breakdown, describe the experimental setup and preliminary results, and propose a relevant performance parameter for candidate accelerator structures.

Cowan, B.; /SLAC

2006-09-07T23:59:59.000Z

380

Predicting threshold and location of laser damage on optical surfaces  

DOE Patents [OSTI]

Disclosed is an apparatus useful in the prediction of the damage threshold of various optical devices, the location of weak spots on such devices and the location, identification, and elimination of optical surface impurities. The apparatus comprises a focused and pulsed laser, a photo electric detector/imaging means, and a timer. The weak spots emit photoelectrons when subjected to laser intensities that are less than the intensity actually required to produce the damage. The weak spots may be eliminated by sustained exposure to the laser beam.

Siekhaus, W.

1985-02-04T23:59:59.000Z

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


381

BDS Thin Film UV Antireflection Laser Damage Competition  

SciTech Connect (OSTI)

UV antireflection coatings are a challenging coating for high power laser applications as exemplified by the use of uncoated Brewster's windows in laser cavities. In order to understand the current laser resistance of UV AR coatings in the industrial and university sectors, a double blind laser damage competition was performed. The coatings have a maximum reflectance of 0.5% at 355 nm at normal incidence. Damage testing will be performed using the raster scan method with a 7.5 ns pulse length on a single testing facility to facilitate direct comparisons. In addition to the laser resistance results, details of deposition processes and coating materials will also be shared.

Stolz, C J

2010-10-26T23:59:59.000Z

382

Measuring Radiation Damage from Heavy Energetic Ions in Aluminum  

SciTech Connect (OSTI)

An intense beam of 122 MeV/u (9.3 GeV) 76Ge ions was stopped in aluminum samples at the Coupled Cyclotron Facility at NSCL, MSU. Attempts were made at ORNL to measure changes in material properties by measuring changes in electrical resistivity and microhardness, and by transmission electron microscopy characterization, for defect density caused by radiation damage, as a function of depth and integrated ion flux. These measurements are relevant for estimating damage to components at a rare isotope beam facility.

Kostin, M., PI-MSU; Ronningen, R., PI-MSU; Ahle, L., PI-LLNL; Gabriel, T., Scientific Investigation and Development; Mansur, L., PI-ORNL; Leonard, K., ORNL; Mokhov, N., FNAL; Niita, K., RIST, Japan

2009-02-21T23:59:59.000Z

383

Crystal Structure of the Chromodomain Helicase DNA-binding Protein 1 (Chd1) DNA-binding Domain in Complex with DNA  

SciTech Connect (OSTI)

Chromatin remodelers are ATP-dependent machines that dynamically alter the chromatin packaging of eukaryotic genomes by assembling, sliding, and displacing nucleosomes. The Chd1 chromatin remodeler possesses a C-terminal DNA-binding domain that is required for efficient nucleosome sliding and believed to be essential for sensing the length of DNA flanking the nucleosome core. The structure of the Chd1 DNA-binding domain was recently shown to consist of a SANT and SLIDE domain, analogous to the DNA-binding domain of the ISWI family, yet the details of how Chd1 recognized DNA were not known. Here we present the crystal structure of the Saccharomyces cerevisiae Chd1 DNA-binding domain in complex with a DNA duplex. The bound DNA duplex is straight, consistent with the preference exhibited by the Chd1 DNA-binding domain for extranucleosomal DNA. Comparison of this structure with the recently solved ISW1a DNA-binding domain bound to DNA reveals that DNA lays across each protein at a distinct angle, yet contacts similar surfaces on the SANT and SLIDE domains. In contrast to the minor groove binding seen for Isw1 and predicted for Chd1, the SLIDE domain of the Chd1 DNA-binding domain contacts the DNA major groove. The majority of direct contacts with the phosphate backbone occur only on one DNA strand, suggesting that Chd1 may not strongly discriminate between major and minor grooves.

Sharma A.; Heroux A.; Jenkins K. R.; Bowman G. D.

2011-12-09T23:59:59.000Z

384

ABBREVIATIONS: AHR, Ah receptor; RACE, rapid amplification of cDNA ends; TCDD, 2,3,7,8-tetrachlorodibenzo-p-dioxin; DRE, dioxin-responsive element; ARNT, Ah receptor nuclear translocator; PAS, Per/Ah receptor nuclear translocator/Ah receptor/Sim; GAPDH, g  

E-Print Network [OSTI]

,3,7,8-tetrachlorodibenzo-p-dioxin; DRE, dioxin-responsive element; ARNT, Ah receptor nuclear translocator; PAS, Per/helix-loop-helix protein that mediates the toxic effects of 2,3,7,8-tetrachlorodibenzo-p- dioxin. A comparison the biological effects of TCDD (or "dioxin") and related planar aromatic compounds (1). Models to describe

Bradfield, Christopher A.

385

Damage & fracture of high-explosive mock subject to cyclic loading  

SciTech Connect (OSTI)

We use four-point bend specimen with a single shallow edge notch to study the fracture process in Mock 900-21, a PBX 9501 high explosive simulant mock. Subject to monotonic loading we determine quantitatively the threshold load for macroscopic crack initiation from the notch tip. The four-point bend specimen is then subject to cyclic loading in such a way that during the first cycle, the applied force approaches but does not exceed the threshold load determined from the monotonic loading test and in the subsequent cycles, the overall maximum deformation is maintained to be equal to that of the first cycle. It is expected and is also confirmed that no macroscopic damage and cracking occur during the first cycle. However, we observe that sizable macroscopic crack is generated and enlarged during the subsequent cycles, even though the applied force never exceeds the threshold load. Details of the process of damage fonnation, accumulation, and crack extension are presented and the mechanical mechanism responsible for such failure process is postulated and discussed.

Liu, Cheng [Los Alamos National Laboratory; Rae, Philip J [Los Alamos National Laboratory; Cady, Carl M [Los Alamos National Laboratory; Lovato, Manuel L [Los Alamos National Laboratory

2011-01-11T23:59:59.000Z

386

Image Processing and control of a programmable spatial light modulator for optic damage protection  

SciTech Connect (OSTI)

The heart of the National Ignition Facility is a megajoule-class laser system consisting of 192 beams used to drive inertial confinement fusion reactions. A recently installed system of programmable, liquid-crystal-based spatial light modulators adds the capability of arbitrarily shaping the spatial beam profiles in order to enhance operational flexibility. Its primary intended use is for introducing 'blocker' obscurations shadowing isolated flaws on downstream optical elements that would otherwise be damaged by high fluence laser illumination. Because an improperly shaped blocker pattern can lead to equipment damage, both the position and shape of the obscurations must be carefully verified prior to high-fluence operations. An automatic alignment algorithm is used to perform detection and estimation of the imposed blocker centroid positions compared to their intended locations. Furthermore, in order to minimize the spatially-varying nonlinear response of the device, a calibration of the local magnification is performed at multiple sub-image locations. In this paper, we describe the control and associated image processing of this device that helps to enhance the safety and longevity of the overall system.

Awwal, A; Leach, R; Brunton, G; Tse, E; Matone, J; Heebner, J

2010-12-06T23:59:59.000Z

387

Swift-heavy-ion-induced damage formation in III-V binary and ternary semiconductors  

SciTech Connect (OSTI)

Damage formation in InP, GaP, InAs, GaAs, and the related ternary alloys Ga{sub 0.50}In{sub 0.50}P and Ga{sub 0.47}In{sub 0.53}As irradiated at room temperature with 185 MeV Au ions was studied using Rutherford backscattering spectroscopy in channeling configuration, transmission electron microscopy, and small-angle x-ray scattering. Despite nearly identical ion-energy loss in these materials, their behavior under swift-heavy-ion irradiation is strikingly different: InP and Ga{sub 0.50}In{sub 0.50}P are readily amorphized, GaP and GaAs remain almost undamaged and InAs and Ga{sub 0.47}In{sub 0.53}As exhibit intermediate behavior. A material-dependent combination of irradiation-induced damage formation and annealing is proposed to describe the different responses of the III-V materials to electronic energy loss.

Schnohr, C. S.; Kluth, P.; Giulian, R.; Llewellyn, D. J.; Byrne, A. P.; Cookson, D. J.; Ridgway, M. C. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Australian Synchrotron, Clayton, Victoria 3168 (Australia); Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

2010-02-15T23:59:59.000Z

388

ap dna endonuclease: Topics by E-print Network  

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

specificity Raines, Ronald T. 2 A DNA and restriction enzyme implementation of Turing Ma (Turing machines; Universal Turing machines; recombinant DNA; nonpalindromic...

389

adenovirus dna sequences: Topics by E-print Network  

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

description of the given DNA string in terms of a smaller set of distinct domain labels. This yields a minimal domain description of a given DNA sequence, significantly...

390

Minor Groove Deformability of DNA: A Molecular Dynamics Free...  

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

Minor Groove Deformability of DNA: A Molecular Dynamics Free EnergySimulation Study. Minor Groove Deformability of DNA: A Molecular Dynamics Free EnergySimulation Study. Abstract:...

391

Electrochemical Branched-DNA Assay for Polymerase Chain Reaction...  

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

Branched-DNA Assay for Polymerase Chain Reaction-Free Detection and Quantification of Oncogenes in Messenger RNA Electrochemical Branched-DNA Assay for Polymerase Chain...

392

adapting dna microarray: Topics by E-print Network  

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

Gene Expression Analysis & R Tutorial 12;DNA Microarrays An R Tutorial Functional Genomics Qiu, Weigang 3 Research tools known as DNA microarrays are Biology and Medicine...

393

archived dna microarrays: Topics by E-print Network  

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

Gene Expression Analysis & R Tutorial 12;DNA Microarrays An R Tutorial Functional Genomics Qiu, Weigang 3 Research tools known as DNA microarrays are Biology and Medicine...

394

Constraint of DNA on Functionalized Graphene Improves Its Biostability...  

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

Constraint of DNA on Functionalized Graphene Improves Its Biostability and Specificity. Constraint of DNA on Functionalized Graphene Improves Its Biostability and Specificity....

395

Development and Application of a Strength and Damage Model for Rock under Dynamic Loading  

SciTech Connect (OSTI)

Simulating the behavior of geologic materials under impact loading conditions requires the use of a constitutive model that includes the effects of bulking, yielding, damage, porous compaction and loading rate on the material response. This paper describes the development, implementation and calibration of a thermodynamically consistent constitutive model that incorporates these features. The paper also describes a computational study in which the model was used to perform numerical simulations of PILE DRIVER, a deeply-buried underground nuclear explosion detonated in granite at the Nevada Test Site. Particle velocity histories, peak velocity and peak displacement as a function of slant range obtained from the code simulations compare favorably with PILE DRIVER data. The simulated attenuation of peak velocity and peak displacement also agrees with the results from several other spherical wave experiments in granite.

Antoun, T H; Lomov, I N; Glenn, L A

2001-03-12T23:59:59.000Z

396

An explicit finite element formulation for dynamic strain localization and damage evolution in metals  

SciTech Connect (OSTI)

An explicit finite element formulation, used to study the behavior and failure mechanisms of metallic materials under high strain rate loading, is presented. The formulation is based on the assumed-strain approach of Fish and Belytschko [1988], which allows localization bands to be embedded within an element, thereby alleviating mesh sensitivity and reducing the required computational effort. The behavior of the material outside localization bands (and of the virgin material prior to the onset of strain localization) is represented using a Gurson-type coupled plasticity-damage model based on the work of Johnson and Addessio [1988]. Assuming adiabatic conditions, the response of the localization band material is represented by a set of constitutive equations for large elasticviscoplastic deformations in metals at high strain rates and high homologous temperatures (see Brown et al. [1989]). Computational results are compared to experimental data for different metallic alloys to illustrate the advantages of the proposed modeling strategy.

Mourad, Hashem M [Los Alamos National Laboratory; Bronkhorst, Curt A [Los Alamos National Laboratory; Addessio, Francis L [Los Alamos National Laboratory

2010-12-16T23:59:59.000Z

397

Modelling of fatigue damage in aluminum cylinder heads. R. Salapeteb  

E-Print Network [OSTI]

. 1. INTRODUCTION Increase in the specific power of Diesel engines leads to severe operating fatigue damage that may cause Diesel engine to fail after a few thousand cycles on the test bench and under severe operating conditions. The alternative heating and cooling of the operative Diesel engine

Paris-Sud XI, Université de

398

Topeka, Kansas, Flood Damage Reduction Project 30 January 2009  

E-Print Network [OSTI]

with and approved by the necessary resource agencies. The long-term environmental and cultural consequences of planTopeka, Kansas, Flood Damage Reduction Project 30 January 2009 Abstract: The recommended plan provides for flood risk management and restores the reliability of the Topeka, Kansas, Levee System located

US Army Corps of Engineers

399

NONLINEAR ACOUSTIC IMAGING OF STRUCTURAL DAMAGES IN LAMINATED COMPOSITES  

E-Print Network [OSTI]

are performed on a carbon fiber/epoxy laminated composite plate with barely visible impact damage and requires an ever increasing accuracy of detection. A good example is the inspection of composite materials been applied to a variety of materials including rocks [4], metals [5-10] and composites [11

Boyer, Edmond

400

Fungal endophytes limit pathogen damage in a tropical tree  

E-Print Network [OSTI]

Fungal endophytes limit pathogen damage in a tropical tree A. Elizabeth Arnold* , Luis Carlos Meji species examined to date harbors endophytic fungi within its asymptomatic aerial tissues, such that endophytes rep- resent a ubiquitous, yet cryptic, component of terrestrial plant communities. Fungal

Bermingham, Eldredge

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


401

Temporary patching of damaged UF{sub 6} cylinders  

SciTech Connect (OSTI)

Patching techniques based on application of epoxy resins have been developed for temporarily repairing UF{sub 6} cylinders which have sustained relatively minor damage and must be safely emptied. The method is considerably faster and simpler than metallurgical weld repairs. Laboratory tests, detailed operational procedures, and case histories of experience at the Portsmouth Gaseous Diffusion Plant are described.

Cardenas, A.L. [Martin Marietta Energy Systems, Inc., OH (United States)

1991-12-31T23:59:59.000Z

402

Automated Damage Diagnosis and Recovery for Remote Robotics  

E-Print Network [OSTI]

; damage may require rapid compensation (eg., power drain due to coverage of solar panels); and repeated that are qualitatively different from the original controller. A number of algorithms based on repeated testing have been only handles pre­ specified error types. The algorithm proposed here is demon­ strated to automatically

Bongard, Josh

403

Automated Damage Diagnosis and Recovery for Remote Robotics  

E-Print Network [OSTI]

; damage may require rapid compensation (eg., power drain due to coverage of solar panels); and repeated that are qualitatively different from the original controller. A number of algorithms based on repeated testing have been only handles pre- specified error types. The algorithm proposed here is demon- strated to automatically

Bongard, Josh

404

Electric heating units in pollination bags avoid damage  

E-Print Network [OSTI]

Electric heating units in pollination bags avoid damage to flowers by spring frost J. CH. FERRAND n'Orlgans Ardon, F 45160 Olivet Summary An effective, cheap and simple heating device was designed by INRA heating, Larix. Controlled crosses are essential for forest tree breeding, but spring frost can destroy

Paris-Sud XI, Université de

405

Specific grinding energy causing thermal damage in precision gear steels  

E-Print Network [OSTI]

of thermal damage for surface grinding of AISI 9310 gear steel using two different grinding wheels and two different coolants. The grinding wheels used for this research are plain alumina wheel-32A80-JVBE and Seeded Gel alumina abrasive-5SG80-JVS...

Hatathodi, Srinivas

2002-01-01T23:59:59.000Z

406

A micromechanics based ductile damage model for anisotropic titanium alloys  

E-Print Network [OSTI]

of internal cavitation. The model is developed from a rigorous micromechanical basis, following well-known previous works in the field. The model incorporates the porosity and void aspect ratio as internal damage variables, and seeks to provide a more accurate...

Keralavarma, Shyam Mohan

2009-05-15T23:59:59.000Z

407

Methods for globally treating silica optics to reduce optical damage  

DOE Patents [OSTI]

A method for preventing damage caused by high intensity light sources to optical components includes annealing the optical component for a predetermined period. Another method includes etching the optical component in an etchant including fluoride and bi-fluoride ions. The method also includes ultrasonically agitating the etching solution during the process followed by rinsing of the optical component in a rinse bath.

Miller, Philip Edward; Suratwala, Tayyab Ishaq; Bude, Jeffrey Devin; Shen, Nan; Steele, William Augustus; Laurence, Ted Alfred; Feit, Michael Dennis; Wong, Lana Louie

2012-11-20T23:59:59.000Z

408

Scaling of fracture length and distributed damage Vladimir Lyakhovsky  

E-Print Network [OSTI]

Scaling of fracture length and distributed damage Vladimir Lyakhovsky The Institute of Earth space scaling except linear relations between fracture length and displacements and thus the determination theoretically of the strength of a body or structure directly. Self-similarity of a fracture

Lyakhovsky, Vladimir

409

Dynamics and Fatigue Damage of Wind Turbine Rotors  

E-Print Network [OSTI]

6 3 RiS0-Rr512 Dynamics and Fatigue Damage of Wind Turbine Rotors during Steady Operation Peter OF WIND TURBINE ROTORS DURING STEADY OPERATION Peter Hauge Madsen, Sten Frandsen, William E. Holley-carrying capacity of a wind turbine rotor with respect to short-term strength and material fatigue are presented

410

Non-Destructive Damage Evaluation Based on Element Strain Energies  

E-Print Network [OSTI]

should apply to 1-D as well as 2-D and 3-D structures with single or multiple damage locations. To achieve the objectives listed above, the following four tasks are addressed: (1) the development of the theoretical foundations of the nondestructive...

Li, Ran

2013-05-01T23:59:59.000Z

411

Proton Irradiation Damage Assessment of Carbon Reinforced Composites  

E-Print Network [OSTI]

Proton Irradiation Damage Assessment of Carbon Reinforced Composites: 2-D & 3-D Weaved Structures carbon-carbon composite ATJ Graphite 3D CC composite AGS Beam-on-Target tests show clearly that carbon composites are better absorbers of thermo- mechanical shock. This is attributed to the very low coeff

McDonald, Kirk

412

IDENTIFICATION OF MATERIAL DAMAGE IN TWO DIMENSIONAL DOMAINS  

E-Print Network [OSTI]

IDENTIFICATION OF MATERIAL DAMAGE IN TWO DIMENSIONAL DOMAINS USING SQUID BASED NDE SYSTEM H on such problems entails quantitative nondestructive evaluation methods in SQUID-based NDE system [1]. It is well, SQUID based nondestructive evaluation (NDE) systems using injection current methods have been recently

413

IDENTIFICATION OF MATERIAL DAMAGE IN TWO DIMENSIONAL DOMAINS  

E-Print Network [OSTI]

IDENTIFICATION OF MATERIAL DAMAGE IN TWO DIMENSIONAL DOMAINS USING SQUID BASED NDE SYSTEM H#ort on such problems entails quantitative nondestructive evaluation methods in SQUID­based NDE system [1]. It is well nondestructive evaluation (NDE) systems using injection current methods have been recently developed [3, 4

414

Collaborative Post-Disaster Damage Mapping via Geo Web Services  

E-Print Network [OSTI]

with geospatial services that can interact in a loosely coupled envir- onment and be used to create more suitable architecture for a collaborative post-disaster damage mapping system. We focus particularly on satellite image-based post-disaster support situations, and present our ideas for a prototype based on this architecture

Köbben, Barend

415

Monitoring Forest Damage Methods and Development in Sweden  

E-Print Network [OSTI]

, fieldwork in the target-tailored inventory of resin top disease, damage by Spruce bark beetle. (photo: S is the most important information that can be obtained from these kinds of inventories. Short variability. Large-scale monitoring, such as that performed in national forest inventories, has good potential

416

TMI-2 core damage: a summary of present knowledge  

SciTech Connect (OSTI)

Extensive fuel damage (oxidation and fragmentation) has occurred and the top approx. 1.5 m of the center portion of the TMI-2 core has relocated. The fuel fragmentation extends outward to slightly beyond one-half the core radius in the direction examined by the CCTV camera. While the radial extent of core fragmentation in other directions was not directly observed, control and spider drop data and in-core instrument data suggest that the core void is roughly symmetrical, although there are a few indications of severe fuel damage extending to the core periphery. The core material fragmented into a broad range of particle sizes, extending down to a few microns. APSR movement data, the observation of damaged fuel assemblies hanging unsupported from the bottom of the reactor upper plenum structure, and the observation of once-molten stainless steel immediately above the active core indicate high temperatures (up to at least 1720 K) extended to the very top of the core. The relative lack of damage to the underside of the plenum structure implies a sharp temperature demarcation at the core/plenum interface. Filter debris and leadscrew deposit analyses indicate extensive high temperature core materials interaction, melting of the Ag-In-Cd control material, and transport of particulate control material to the plenum and out of the vessel.

Owen, D.E.; Mason, R.E.; Meininger, R.D.; Franz, W.A.

1983-01-01T23:59:59.000Z

417

DAMAGE DETECTION IN COMPOSITES BY NONCONTACT LASER Byeongjin Park  

E-Print Network [OSTI]

, Composite structures, Wind blade. INTRODUCTION Composite materials are widely used for various industries. The feasibility of the proposed technique is examined by localizing a delamination in a real 10 kW wind turbine blade. KEYWORDS : Laser ultrasonics, Damage detection and localization, Time-of-flight triangulation

Paris-Sud XI, Université de

418

Evaluation of the serum catalase and myeloperoxidase activities in chronic arsenic-exposed individuals and concomitant cytogenetic damage  

SciTech Connect (OSTI)

Chronic arsenic exposure through contaminated drinking water is a major environmental health issue. Chronic arsenic exposure is known to exert its toxic effects by a variety of mechanisms, of which generation of reactive oxygen species (ROS) is one of the most important. A high level of ROS, in turn, leads to DNA damage that might ultimately culminate in cancer. In order to keep the level of ROS in balance, an array of enzymes is present, of which catalase (CAT) and myeloperoxidase (MPO) are important members. Hence, in this study, we determined the activities of these two enzymes in the sera and chromosomal aberrations (CA) in peripheral blood lymphocytes in individuals exposed and unexposed to arsenic in drinking water. Arsenic in drinking water and in urine was used as a measure of exposure. Our results show that individuals chronically exposed to arsenic have significantly higher CAT and MPO activities and higher incidence of CA. We found moderate positive correlations between CAT and MPO activities, induction of CA and arsenic in urine and water. These results indicate that chronic arsenic exposure causes higher CAT and MPO activities in serum that correlates with induction of genetic damage. We conclude that the serum levels of these enzymes might be used as biomarkers of early arsenic exposure induced disease much before the classical dermatological symptoms of arsenicosis begin to appear.

Banerjee, Mayukh; Banerjee, Nilanjana; Ghosh, Pritha [Molecular and Human Genetics Division, Indian Institute of Chemical Biology, Kolkata (India); Das, Jayanta K. [Department of Dermatology, West Bank Hospital, Howrah (India); Basu, Santanu [Department of General Medicine, Sri Aurobindo Seva Kendra, Kolkata (India); Sarkar, Ajoy K. [Peerless Hospital and B.K Roy Research Centre, Kolkata (India); States, J. Christopher, E-mail: jcstates@louisville.ed [Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY (United States); Center for Environmental Genomics and Integrative Biology, University of Louisville, Louisville, KY (United States); Giri, Ashok K., E-mail: akgiri15@yahoo.co [Molecular and Human Genetics Division, Indian Institute of Chemical Biology, Kolkata (India)

2010-11-15T23:59:59.000Z

419

Method of quantitating dsDNA  

DOE Patents [OSTI]

A method for quantitating dsDNA in an aqueous sample solution containing an unknown amount of dsDNA. A first aqueous test solution containing a known amount of a fluorescent dye-dsDNA complex and at least one fluorescence-attenutating contaminant is prepared. The fluorescence intensity of the test solution is measured. The first test solution is diluted by a known amount to provide a second test solution having a known concentration of dsDNA. The fluorescence intensity of the second test solution is measured. Additional diluted test solutions are similarly prepared until a sufficiently dilute test solution having a known amount of dsDNA is prepared that has a fluorescence intensity that is not attenuated upon further dilution. The value of the maximum absorbance of this solution between 200-900 nanometers (nm), referred to herein as the threshold absorbance, is measured. A sample solution having an unknown amount of dsDNA and an absorbance identical to that of the sufficiently dilute test solution at the same chosen wavelength is prepared. Dye is then added to the sample solution to form the fluorescent dye-dsDNA-complex, after which the fluorescence intensity of the sample solution is measured and the quantity of dsDNA in the sample solution is determined. Once the threshold absorbance of a sample solution obtained from a particular environment has been determined, any similarly prepared sample solution taken from a similar environment and having the same value for the threshold absorbance can be quantified for dsDNA by adding a large excess of dye to the sample solution and measuring its fluorescence intensity.

Stark, Peter C. (Los Alamos, NM); Kuske, Cheryl R. (Los Alamos, NM); Mullen, Kenneth I. (Los Alamos, NM)

2002-01-01T23:59:59.000Z

420

DNA fragment sizing and sorting by laser-induced fluorescence  

DOE Patents [OSTI]

A method is provided for sizing DNA fragments using high speed detection systems, such as flow cytometry to determine unique characteristics of DNA pieces from a sample. In one characterization the DNA piece is fragmented at preselected sites to produce a plurality of DNA fragments. The DNA piece or the resulting DNA fragments are treated with a dye effective to stain stoichiometrically the DNA piece or the DNA fragments. The fluorescence from the dye in the stained fragments is then examined to generate an output functionally related to the number of nucleotides in each one of the DNA fragments. In one embodiment, the intensity of the fluorescence emissions from each fragment is linearly related to the fragment length. The distribution of DNA fragment sizes forms a characterization of the DNA piece for use in forensic and research applications.

Hammond, Mark L. (Angier, NC); Jett, James H. (Los Alamos, NM); Keller, Richard A. (Los Alamos, NM); Marrone, Babetta L. (Los Alamos, NM); Martin, John C. (Los Alamos, NM)

1996-01-01T23:59:59.000Z

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


421

Strategic petroleum reserve caverns casing damage update 1997  

SciTech Connect (OSTI)

Hanging casing strings are used for oil and brine transfer in the domal salt storage caverns of the Strategic Petroleum Reserve (SPR). Damage to these casings is of concern because hanging string replacement is costly and because of implications on cavern stability. Although the causes of casing damage are not always well defined, many events leading to damage are assumed to be the result of salt falls impacting the hanging strings. However, in some cases, operational aspects may be suspected. The history of damage to hanging strings is updated in this study to include the most recent events. Potential general domal and local operational and material factors that could influence the tendency for caverns to have salt falls are examined in detail. As a result of this examination, general factors, such as salt dome anomalies and crude type, and most of the operational factors, such as geometry, location and depressurizations, are not believed to be primary causes of casing damage. Further analysis is presented of the accumulation of insolubles during cavern solutioning and accumulation of salt fall material on the cavern floor. Inaccuracies in sump geometry probably make relative cavern insolubles contents uncertain. However, determination of the salt fall accumulations, which are more accurate, suggest that the caverns with the largest salt fall accumulations show the greatest number of hanging string events. There is good correlation between the accumulation rate and the number of events when the event numbers are corrected to an equivalent number for a single hanging string in a quiescent, operating cavern. The principal factor that determines the propensity for a cavern to exhibit this behavior is thought to be the effect of impurity content on the fracture behavior of salt.

Munson, D.E.; Molecke, M.A.; Neal, J.T. [and others

1998-01-01T23:59:59.000Z

422

Electrochemical DNA biosensor for detection of porcine oligonucleotides using ruthenium(II) complex as intercalator label redox  

SciTech Connect (OSTI)

A DNA biosensor detection of oligonucleotides via the interactions of porcine DNA with redox active complex based on the electrochemical transduction is described. A ruthenium(II) complex, [Ru(bpy){sub 2}(PIP)]{sup 2+}, (bpy = 2,2?bipyridine, PIP = 2-phenylimidazo[4,5-f[[1,10-phenanthroline]) as DNA label has been synthesized and characterized by 1H NMR and mass spectra. The study was carried out by covalent bonding immobilization of porcine aminated DNA probes sequences on screen printed electrode (SPE) modified with succinimide-acrylic microspheres and [Ru(bpy){sub 2}(PIP)]{sup 2+} was used as electrochemical redox intercalator label to detect DNA hybridization event. Electrochemical detection was performed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) over the potential range where the ruthenium (II) complex was active. The results indicate that the interaction of [Ru(bpy){sub 2}(PIP)]{sup 2+} with hybridization complementary DNA has higher response compared to single-stranded and mismatch complementary DNA.

Halid, Nurul Izni Abdullah; Hasbullah, Siti Aishah; Heng, Lee Yook; Karim, Nurul Huda Abd [School of Chemical Sciences and Food Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan (Malaysia); Ahmad, Haslina; Harun, Siti Norain [Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400, Serdang, Selangor (Malaysia)

2014-09-03T23:59:59.000Z

423

ISET Journal of Earthquake Technology, Paper No. 475, Vol. 44, No. 1, March 2007, pp. 2537 RESPONSE SPECTRAAS A USEFUL DESIGN AND ANALYSIS TOOL  

E-Print Network [OSTI]

vulnerability, and post earthquake estimates of potential damage of buildings. KEYWORDS: Response Spectra. This includes easy to use graphical methods that compare the seismic demand represented by a response spectrum­37 RESPONSE SPECTRAAS A USEFUL DESIGN AND ANALYSIS TOOL FOR PRACTICING STRUCTURAL ENGINEERS Sigmund A. Freeman

Gupta, Vinay Kumar

424

Nucleotide insertion initiated by van der Waals interaction during polymerase beta DNA replication  

E-Print Network [OSTI]

Immortality will remain a fantasy for as long as aging is determined by the erroneous biochemical reactions during a particular DNA replication. The replication and base excision repair mechanism, associated to eukaryotic DNA polymerase-beta enzyme are central to maintaining a healthy cell. Here, we give a series of unambiguous theoretical analyses and prove that the exclusive biochemical reaction involved in a single nucleotide insertion into the DNA primer can be efficiently tracked using the renormalized van der Waals interaction of the stronger type, and the Hermansson blue-shifting hydrogen bond effect. We found that there are two biochemical steps involved to complete the insertion of a single dCTP into the 3' end of a DNA primer. First, the O3' (from a DNA primer) initiates the nucleophilic attack on P_alpha?(from an incoming dCTP), in response, O3_alpha (bonded to P_alpha) retaliates by interacting with H' (bonded to O3'). These interactions are shown to be strongly interdependent and require the form...

Arulsamy, Andrew Das

2011-01-01T23:59:59.000Z

425

Sequential addition of short DNA oligos in DNA-polymerase-based synthesis reactions  

DOE Patents [OSTI]

A method of preselecting a multiplicity of DNA sequence segments that will comprise the DNA molecule of user-defined sequence, separating the DNA sequence segments temporally, and combining the multiplicity of DNA sequence segments with at least one polymerase enzyme wherein the multiplicity of DNA sequence segments join to produce the DNA molecule of user-defined sequence. Sequence segments may be of length n, where n is an odd integer. In one embodiment the length of desired hybridizing overlap is specified by the user and the sequences and the protocol for combining them are guided by computational (bioinformatics) predictions. In one embodiment sequence segments are combined from multiple reading frames to span the same region of a sequence, so that multiple desired hybridizations may occur with different overlap lengths.

Gardner, Shea N; Mariella, Jr., Raymond P; Christian, Allen T; Young, Jennifer A; Clague, David S

2013-06-25T23:59:59.000Z

426

Fractal mechanism for characterizing singularity of mode shape for damage detection  

SciTech Connect (OSTI)

Damage is an ordinary physical phenomenon jeopardizing structural safety; damage detection is an ongoing interdisciplinary issue. Waveform fractal theory has provided a promising resource for detecting damage in plates while presenting a concomitant problem: susceptibility to false features of damage. This study proposes a fractal dimension method based on affine transformation to address this problem. Physical experiments using laser measurement demonstrate that this method can substantially eliminate false features of damage and accurately identify complex cracks in plates, providing a fundamental mechanism that brings the merits of waveform fractal theory into full play in structural damage detection applications.

Cao, M. S. [Department of Engineering Mechanics, Hohai University, Nanjing 210098 (China)] [Department of Engineering Mechanics, Hohai University, Nanjing 210098 (China); Ostachowicz, W. [Institute of Fluid-Flow Machinery, Polish Academy of Sciences, ul. Fiszera 14, 80-952 Gdansk (Poland) [Institute of Fluid-Flow Machinery, Polish Academy of Sciences, ul. Fiszera 14, 80-952 Gdansk (Poland); Faculty of Automotive and Construction Machinery, Warsaw University of Technology, Narbutta 84, 02-524 Warsaw (Poland); Bai, R. B., E-mail: bairunbo@gmail.com [Department of Engineering Mechanics, Shandong Agricultural University, Taian 271000 (China); Radzie?ski, M. [Institute of Fluid-Flow Machinery, Polish Academy of Sciences, ul. Fiszera 14, 80-952 Gdansk (Poland)] [Institute of Fluid-Flow Machinery, Polish Academy of Sciences, ul. Fiszera 14, 80-952 Gdansk (Poland)

2013-11-25T23:59:59.000Z

427

Linear Thermodynamics of Rodlike DNA Filtration  

E-Print Network [OSTI]

Linear thermodynamics transportation theory is employed to study filtration of rodlike DNA molecules. Using the repeated nanoarray consisting of alternate deep and shallow regions, it is demonstrated that the complex ...

Li, Zirui

428

Intriguing DNA Editor Has a Structural Trigger  

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

generating a lot of excitement because, unlike earlier genome-editing tools, its basic architecture doesn't have to be rebuilt each time a new section of DNA is targeted; it...

429

The Initiation of Bacterial DNA Replication  

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

that the ATP-DnaA active site is in a closed configuration, which allows it to bind nucleotides using conserved residues from neighboring AAA+ protomers. The precise geometry of...

430

Deoxyribose oxidation chemistry and endogenous DNA adducts  

E-Print Network [OSTI]

Endogenous and exogenous oxidants react with cellular macromolecules to generate a variety of electrophiles that react with DNA produce cytotoxic and mutagenic adducts. One source of such electrophiles is deoxyribose in ...

Zhou, Xinfeng

2006-01-01T23:59:59.000Z

431

Modeling the mechanical response of PBX 9501  

SciTech Connect (OSTI)

An engineering overview of the mechanical response of Plastic-Bonded eXplosives (PBXs), specifically PBX 9501, will be provided with emphasis on observed mechanisms associated with different types of mechanical testing. Mechanical tests in the form of uniaxial tension, compression, cyclic loading, creep (compression and tension), and Hopkinson bar show strain rate and temperature dependence. A range of mechanical behavior is observed which includes small strain recoverable response in the form of viscoelasticity; change in stiffness and softening beyond peak strength due to damage in the form microcracks, debonding, void formation and the growth of existing voids; inelastic response in the form of irrecoverable strain as shown in cyclic tests, and viscoelastic creep combined with plastic response as demonstrated in creep and recovery tests. The main focus of this paper is to elucidate the challenges and issues involved in modeling the mechanical behavior of PBXs for simulating thermo-mechanical responses in engineering components. Examples of validation of a constitutive material model based on a few of the observed mechanisms will be demonstrated against three point bending, split Hopkinson pressure bar and Brazilian disk geometry.

Ragaswamy, Partha [Los Alamos National Laboratory; Lewis, Matthew W [Los Alamos National Laboratory; Liu, Cheng [Los Alamos National Laboratory; Thompson, Darla G [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

432

Design of Autonomous DNA Cellular Automata , Sudheer Sahu  

E-Print Network [OSTI]

Design of Autonomous DNA Cellular Automata Peng Yin ¡ , Sudheer Sahu ¡ , Andrew J. Turberfield cellular computing devices, i.e. autonomous nano-mechanical DNA computing devices embedded in DNA lattices. As a prototype of such devices, we recently reported the design of an Autonomous DNA Turing Machine, which

Yin, Peng

433

Recombinant DNA Research in Human Subjects Duke Institutional Biosafety Committee  

E-Print Network [OSTI]

/2010 Summary. All Duke research using recombinant DNA (rDNA) in human subjects must comply with the NIH Guidelines for Research involving Recombinant DNA Molecules (available at http://oba.od.nih.gov/rdna/nih Biosafety Committee (IBC) [NIH Guidelines Section III-C and III-C-1]. The NIH defines rDNA broadly

434

Dual wavelength laser damage testing for high energy lasers.  

SciTech Connect (OSTI)

As high energy laser systems evolve towards higher energies, fundamental material properties such as the laser-induced damage threshold (LIDT) of the optics limit the overall system performance. The Z-Backlighter Laser Facility at Sandia National Laboratories uses a pair of such kiljoule-class Nd:Phosphate Glass lasers for x-ray radiography of high energy density physics events on the Z-Accelerator. These two systems, the Z-Beamlet system operating at 527nm/ 1ns and the Z-Petawatt system operating at 1054nm/ 0.5ps, can be combined for some experimental applications. In these scenarios, dichroic beam combining optics and subsequent dual wavelength high reflectors will see a high fluence from combined simultaneous laser exposure and may even see lingering effects when used for pump-probe configurations. Only recently have researchers begun to explore such concerns, looking at individual and simultaneous exposures of optics to 1064 and third harmonic 355nm light from Nd:YAG [1]. However, to our knowledge, measurements of simultaneous and delayed dual wavelength damage thresholds on such optics have not been performed for exposure to 1054nm and its second harmonic light, especially when the pulses are of disparate pulse duration. The Z-Backlighter Facility has an instrumented damage tester setup to examine the issues of laser-induced damage thresholds in a variety of such situations [2] . Using this damage tester, we have measured the LIDT of dual wavelength high reflectors at 1054nm/0.5ps and 532nm/7ns, separately and spatially combined, both co-temporal and delayed, with single and multiple exposures. We found that the LIDT of the sample at 1054nm/0.5ps can be significantly lowered, from 1.32J/cm{sup 2} damage fluence with 1054/0.5ps only to 1.05 J/cm{sup 2} with the simultaneous presence of 532nm/7ns laser light at a fluence of 8.1 J/cm{sup 2}. This reduction of LIDT of the sample at 1054nm/0.5ps continues as the fluence of 532nm/7ns laser light simultaneously present increases. The reduction of LIDT does not occur when the 2 pulses are temporally separated. This paper will also present dual wavelength LIDT results of commercial dichroic beam-combining optics simultaneously exposed with laser light at 1054nm/2.5ns and 532nm/7ns.

Atherton, Briggs W.; Rambo, Patrick K.; Schwarz, Jens; Kimmel, Mark W.

2010-05-01T23:59:59.000Z

435

Precursors to potential severe core damage accidents: 1994, a status report. Volume 21: Main report and appendices A--H  

SciTech Connect (OSTI)

Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 {times} 10{sup {minus}6}. These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1.

Belles, R.J.; Cletcher, J.W.; Copinger, D.A.; Vanden Heuvel, L.N. [Oak Ridge National Lab., TN (United States); Dolan, B.W.; Minarick, J.W. [Oak Ridge National Lab., TN (United States)]|[Science Applications International Corp., Oak Ridge, TN (United States)

1995-12-01T23:59:59.000Z

436

Experimental evaluation of a constitutive model for inelastic flow and damage evolution in solids subjected to triaxial compression  

SciTech Connect (OSTI)

Recent concern over the potential for creep induced development of a damaged rock zone adjacent to shafts and rooms at the Waste Isolation Pilot Plant (WIPP) has motivated the formulation of a coupled constitutive description of continuum salt creep and damage. This constitutive model gives time-dependent inelastic flow and pressure-sensitive damage in crystalline solids. Initially the constitutive model was successfully used to simulate multiaxial, i.e. true triaxial, experiments obtained at relatively high, 2.5 to 20 MPa, confining pressures. Predictions of the complete creep curve, including the heretofore unmodeled tertiary creep, were also demonstrated. However, comparisons of model predictions with data were hampered because the bulk of the creep data existing on WIPP salt was intentionally obtained under confining pressures typically greater than 15 MPa, in an attempt to match the underground in situ lithostatic pressure level. It was realized that the high confining pressures suppressed tertiary creep and resulted in better defined steady state creep responses. To address the tertiary creep process directly, a number of creep tests were conducted at lower confining pressures for the explicit purpose of creating dilatant behavior.

Fossum, A.F.; Brodsky, N.S. (RE/SPEC, Inc., Rapid City, SD (United States)); Chan, K.S. (Southwest Research Inst., San Antonio, TX (United States)); Munson, D.E. (Sandia National Labs., Albuquerque, NM (United States))

1992-01-01T23:59:59.000Z

437

Experimental evaluation of a constitutive model for inelastic flow and damage evolution in solids subjected to triaxial compression  

SciTech Connect (OSTI)

Recent concern over the potential for creep induced development of a damaged rock zone adjacent to shafts and rooms at the Waste Isolation Pilot Plant (WIPP) has motivated the formulation of a coupled constitutive description of continuum salt creep and damage. This constitutive model gives time-dependent inelastic flow and pressure-sensitive damage in crystalline solids. Initially the constitutive model was successfully used to simulate multiaxial, i.e. true triaxial, experiments obtained at relatively high, 2.5 to 20 MPa, confining pressures. Predictions of the complete creep curve, including the heretofore unmodeled tertiary creep, were also demonstrated. However, comparisons of model predictions with data were hampered because the bulk of the creep data existing on WIPP salt was intentionally obtained under confining pressures typically greater than 15 MPa, in an attempt to match the underground in situ lithostatic pressure level. It was realized that the high confining pressures suppressed tertiary creep and resulted in better defined steady state creep responses. To address the tertiary creep process directly, a number of creep tests were conducted at lower confining pressures for the explicit purpose of creating dilatant behavior.

Fossum, A.F.; Brodsky, N.S. [RE/SPEC, Inc., Rapid City, SD (United States); Chan, K.S. [Southwest Research Inst., San Antonio, TX (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

1992-12-31T23:59:59.000Z

438

HAZARDOUS MATERIALS EMERGENCY RESPONSE  

E-Print Network [OSTI]

ANNEX Q HAZARDOUS MATERIALS EMERGENCY RESPONSE #12;ANNEX Q - HAZARDOUS MATERIALS EMERGENCY RESPONSE 03/10/2014 v.2.0 Page Q-1 PROMULGATION STATEMENT Annex Q: Hazardous Materials Emergency Response, and contents within, is a guide to how the University conducts a response specific to a hazardous materials

439

Advanced Demand Responsive Lighting  

E-Print Network [OSTI]

Advanced Demand Responsive Lighting Host: Francis Rubinstein Demand Response Research Center demand responsive lighting systems ­ Importance of dimming ­ New wireless controls technologies · Advanced Demand Responsive Lighting (commenced March 2007) #12;Objectives · Provide up-to-date information

440

Damage and rupture mechanisms in an austenoferritic duplex steel  

SciTech Connect (OSTI)

The influence of ageing on damage and rupture mechanisms in an austenoferritic duplex stainless steel is studied using conventional straining and impact toughness testing at 20 C and 320 C, and in situ SEM straining at 20 C. While the as-received alloy fails in a ductile mode, damage in the aged material starts with cleavage nucleation in ferrite. The authors show that, owing to the bipercolated topology of the alloy, these cleavage cracks can propagate while passing round austenite ligaments whose plastic stretching controls the crack extension. The variations with strain of both the crack size and the average crack separation are computed analytically and their comparison gives a good prediction of ductility.

Verhaeghe, B.; Louchet, F.; Brechet, Y. [LTPCM-CNRS, St. Martin d`Heres (France). Groupe Physique du Metal] [LTPCM-CNRS, St. Martin d`Heres (France). Groupe Physique du Metal; Massoud, J.P. [EDF, Moret sur Loing (France)] [EDF, Moret sur Loing (France)

1997-05-01T23:59:59.000Z

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


441

Constitutive representation of damage development and healing in WIPP salt  

SciTech Connect (OSTI)

There has been considerable interest in characterizing and modeling the constitutive behavior of rock salt with particular reference to long-term creep and creep failure. The interest is motivated by the projected use of excavated rooms in salt rock formations as repositories for nuclear waste. It is presumed that closure of those rooms by creep ultimately would encapsulate the waste material, resulting in its effective isolation. A continuum mechanics approach for treating damage healing is formulated as part of a constitutive model for describing coupled creep, fracture, and healing in rock salt. Formulation of the healing term is, described and the constitutive model is evaluated against experimental data of rock salt from the Waste Isolation Pilot Plant (WIPP) site. The results indicate that healing anistropy in WIPP salt can be modeled with an appropriate power-conjugate equivalent stress, kinetic equation, and evolution equation for damage healing.

Chan, K.S.; Bodner, S.R. [Southwest Research Inst., San Antonio, TX (United States); Fossum, A.F [RE/SPEC, Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

1994-12-31T23:59:59.000Z

442

Assessment of damage to geomembrane liners by shredded scrap tires  

SciTech Connect (OSTI)

This paper presents the results of a field and laboratory study performed to assess damage to the geomembrane liner caused by using shredded scrap tires as a leachate drainage layer material in landfills. The field testing was performed to assess the damage that occurred to the geomembrane liner during construction and included nine tests conducted with different combinations of tire chip size and thickness, both with a geotextile and without a geotextile overlying the geomembrane, and under different loading conditions. The laboratory testing was performed to characterize the shredded tires, particularly their size distribution, hydraulic conductivity, compressibility, and chemical resistance. The laboratory testing also included performing simulation testing to determine the extent of damage that occurs to the geomembrane liner by the shredded tires under long-term waste-loading conditions. the damage that occurred to the geomembrane liners in both field tests and simulated laboratory tests was determined by visual observations as well as by conducting multi-axial tension tests, wide strip tension tests, and water vapor transmission tests on the exhumed geomembrane samples. Based on these results, a 0.46-m thick layer of secondary shred tire chips, with an average size of 7.6 cm, placed over a 543-g/m{sup 2} geotextile installed over a geomembrane liner using low-ground-pressure (<58 kPa) equipment was determined to provide adequate protection in the geomembrane liner during construction. The degree of protection offered under long-term loading conditions depends on the normal stress and the random orientation of the shredded tire chips at the geomembrane interface.

Reddy, K.R.; Saichek, R.E. [Univ. of Illinois, Chicago, IL (United States). Dept. of Civil and Materials Engineering

1998-12-01T23:59:59.000Z

443

Building Damage, Death and Downtime Risk Attenuation in Earthquakes  

E-Print Network [OSTI]

value over a specified amount of time, can be obtained. This was a great development in the field of probabilistic seismic hazard analysis. Kennedy et al. (1980) conducted research to study the safety of the Oyster Creek nuclear power plant... 2D structural model developed in SAP 2000; and (c) plan of ?Redbook Building? ....... 16 Figure 4 ?Scenario-based? 3d loss model: (a) seismic hazard intensity-attenuation model; (b) structural analysis; (c) damage analysis; and (d) loss...

Huang, Yinghui

2012-07-16T23:59:59.000Z

444

Microstructural Characterization of Material Properties and Damage in Asphalt Composites  

E-Print Network [OSTI]

MICROSTRUCTURAL CHARACTERIZATION OF MATERIAL PROPERTIES AND DAMAGE IN ASPHALT COMPOSITES A Thesis by SARA MOHAMMAD KHORASANI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... Engineering Copyright 2013 Sara Mohammad Khorasani ii ABSTRACT Asphalt composites are used to construct 90% of roads in the United States. These composites consist of asphalt binder, which is a product of the refinery process of oil, aggregates...

Mohammad Khorasani, Sara

2013-05-03T23:59:59.000Z

445

Damage Assessment and Control of Wireworms in Grain Sorghum.  

E-Print Network [OSTI]

- plete block design with three replications. Plc': were four rows, 50 feet long. Five days following planting on May 9, 19": 1 wireworm damaged seed and wireworm number- were determined in one linear row foot in err ! plot. After plant emergence...) / insecticides / Texas. color, religion, sex, age or national origin. The Texas Agricultural Experiment Station, J. E. Miller, Director, College Station, Texas 2M - 9-76 ...

Teetes, George L.

1976-01-01T23:59:59.000Z

446

NMSLO Water Lease Damage Bond | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data CenterFranconia, Virginia: Energy Resources Jump to:46 -Energieprojekte3Information Exploration/Development Water EasementLeaseofDamage

447

Mechanisms and impact of damage resulting from hydraulic fracturing. Topical report, May 1995-July 1996  

SciTech Connect (OSTI)

This topical report documents the mechanisms of formation damage following hydraulic fracturing and their impact upon gas well productivity. The categories of damage reviewed include absolute or matrix permeability damage, relative permeability alterations, the damage of natural fracture permeability mechanisms and proppant conductivity impairment. Case studies are reviewed in which attempts are made to mitigate each of the damage types. Industry surveys have been conducted to determine the perceptions of the industry on the topic of formation damage following hydraulic fracturing and to identify key formations in which formation damage is a problem. From this information, technical hurdles and new technology needs are identified and estimates are made of the benefits of developing and applying minimum formation damage technology.

Penny, G.S.; Conway, M.W.; Almond, S.W.; Himes, R.; Nick, K.E.

1996-08-01T23:59:59.000Z

448

Review: Clearing the Air: The Health and Economic Damages of Air Pollution in China  

E-Print Network [OSTI]

and Economic Damages of Air Pollution in China Mun S. Ho andEconomic Damages of Air Pollution in China. Cambridge, MA:the assessment of air pollution and its health and economic

Lee, Joseph

2009-01-01T23:59:59.000Z

449

Piezoelectric-based in-situ damage detection of composite materials for structural health monitoring systems  

E-Print Network [OSTI]

Cost-effective and reliable damage detection is critical for the utilization of composite materials. This thesis presents the conclusions of an analytical and experimental survey of candidate methods for in-situ damage ...

Kessler, Seth Stovack, 1977-

2002-01-01T23:59:59.000Z

450

Damage Modeling and Life Extending Control of a Boiler-Turbine System1  

E-Print Network [OSTI]

Damage Modeling and Life Extending Control of a Boiler-Turbine System1 Donglin Li Tongwen Chen2 hierarchical LEC structure and apply it to a typ- ical boiler system. There are two damage models

Marquez, Horacio J.

451

E-Print Network 3.0 - area damage detection Sample Search Results  

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

loss due to loss of stems Safety issues Canopy damage Ring Barking Any thin... -barked tree species 10-40 yrs old Grey Squirrel Bark Stripping Damage Deformed stems 12 Source:...

452

Use of CFRP Overlays to Repair Fatigue Damage in Steel Bridge Girders and Components  

E-Print Network [OSTI]

Fatigue damage in steel girder bridges built prior to the mid-1980s is common due to distortion-induced fatigue. Different repair techniques have been developed and implemented to retrofit bridges of this era with existing fatigue damage...

Gangel, Regan Elisabeth

2012-05-31T23:59:59.000Z

453

Martin Marietta Energy Systems, Inc. comprehensive earthquake management plan: Engineering survey building damage assessment training manual  

SciTech Connect (OSTI)

The training objectives are: differentiate between the various levels of damage caused to buildings and structures by an earthquake and classify them as to their safety of occupancy, extent of damage, and resources needed for recovery/repair.

Not Available

1990-01-01T23:59:59.000Z

454

E-Print Network 3.0 - acari eriophyidae damage Sample Search...  

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

damage Search Powered by Explorit Topic List Advanced Search Sample search results for: acari eriophyidae damage Page: << < 1 2 3 4 5 > >> 1 216 Florida Entomologist 85(1) March...

455

DAMAGE DETECTION METHODS ON WIND TURBINE BLADE TESTING WITH WIRED AND WIRELESS ACCELEROMETER SENSORS  

E-Print Network [OSTI]

DAMAGE DETECTION METHODS ON WIND TURBINE BLADE TESTING WITH WIRED AND WIRELESS ACCELEROMETER turbine blade. We compare the data collected from the wireless sensors against wired sensors for nonstationary blade excitations. KEYWORDS : Structural Health Monitoring, Damage Detection, Wind Turbine

Paris-Sud XI, Université de

456

Simple Method for Estimating and Comparing of X-Ray Damage Rates...  

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

Method for Estimating and Comparing of X-Ray Damage Rates. Simple Method for Estimating and Comparing of X-Ray Damage Rates. Abstract: This note describes an approach for...

457

Aligned composite structures for mitigation of impact damage and resistance to wear in dynamic environments  

DOE Patents [OSTI]

Fibrous monolith composites having architectures that provide increased flaw insensitivity, improved hardness, wear resistance and damage tolerance and methods of manufacture thereof are provided for use in dynamic environments to mitigate impact damage and increase wear resistance.

Mulligan, Anthony C.; Rigali, Mark J.; Sutaria, Manish P.; Popovich, Dragan; Halloran, Joseph P.; Fulcher, Michael L.; Cook, Randy C.

2005-12-13T23:59:59.000Z

458

Aligned composite structures for mitigation of impact damage and resistance to wear in dynamic environments  

DOE Patents [OSTI]

Fibrous monolith composites having architectures that provide increased flaw insensitivity, improved hardness, wear resistance and damage tolerance and methods of manufacture thereof are provided for use in dynamic environments to mitigate impact damage and increase wear resistance.

Mulligan, Anthony C. (Tucson, AZ); Rigali, Mark J. (Tucson, AZ); Sutaria, Manish P. (Malden, MA); Popovich, Dragan (Redmond, WA); Halloran, Joseph P. (Tucson, AZ); Fulcher, Michael L. (Tucson, AZ); Cook, Randy C. (Tucson, AZ)

2009-04-14T23:59:59.000Z

459

Damage analysis and fundamental studies. Quarterly progress report, October-December 1979  

SciTech Connect (OSTI)

Progress on each of the following topics is outlined: (1) rotating target neutron source, (2) fusion materials irradiation test facility, (3) environmental characterization, (4) damage production, and (5) damage microstructure evolution and mechanical behavior. (MOW)

None

1980-02-01T23:59:59.000Z

460

Beam damage of poly(vinyl chloride) [PVC] as observed by x-ray...  

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

damage of poly(vinyl chloride) PVC as observed by x-ray photoelectron spectroscopy at 143 K, 303 K and 373 K. Beam damage of poly(vinyl chloride) PVC as observed by x-ray...

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


461

Beam Damage of Poly(Vinyl Chloride) [PVC] Film as Observed by...  

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

Damage of Poly(Vinyl Chloride) PVC Film as Observed by X-ray Photoelectron Spectroscopy. Beam Damage of Poly(Vinyl Chloride) PVC Film as Observed by X-ray Photoelectron...

462

E-Print Network 3.0 - air pollution damage Sample Search Results  

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

damage Search Powered by Explorit Topic List Advanced Search Sample search results for: air pollution damage Page: << < 1 2 3 4 5 > >> 1 www.ext.vt.edu Produced by Communications...

463

SALT DAMAGE CRITERION PROOF-OF-CONCEPT RESEARCH  

SciTech Connect (OSTI)

The purpose of this study was to conduct a field-scale application demonstrating the use of continuum damage mechanics to determine the minimum allowable operating pressure of compressed natural gas storage caverns in salt formations. A geomechanical study was performed of two natural gas storage caverns (one existing and one planned) utilizing state-of-the-art salt mechanics to assess the potential for cavern instability and collapse. The geomechanical study consisted primarily of laboratory testing, theoretical development, and analytical/numerical tasks. A total of 50 laboratory tests was performed on salt specimens to aid in the development and definition of the material model used to predict the behavior of rock salt. Material model refinement was performed that improved the predictive capability of modeling salt during damage healing, recovery of work-hardened salt, and the behavior of salt at stress states other than triaxial compression. Results of this study showed that the working gas capacity of the existing cavern could be increased by 18 percent and the planned cavern could be increased by 8 percent using the proposed method compared to a conventional stress-based method. Further refinement of the continuum damage model is recommended to account for known behavior of salt at stress conditions other than triaxial compression that is not characterized accurately by the existing model.

Kerry L. DeVries; Kirby D. Mellegard; Gary D. Callahan

2002-11-01T23:59:59.000Z

464

A Nucleotide-Analogue-Induced Gain of Function Corrects the Error-Prone Nature of Human DNA Polymerase iota  

SciTech Connect (OSTI)

Y-family DNA polymerases participate in replication stress and DNA damage tolerance mechanisms. The properties that allow these enzymes to copy past bulky adducts or distorted template DNA can result in a greater propensity for them to make mistakes. Of the four human Y-family members, human DNA polymerase iota (hpol{iota}) is the most error-prone. In the current study, we elucidate the molecular basis for improving the fidelity of hpol{iota} through use of the fixed-conformation nucleotide North-methanocarba-2{prime}-deoxyadenosine triphosphate (N-MC-dATP). Three crystal structures were solved of hpol{iota} in complex with DNA containing a template 2{prime}-deoxythymidine (dT) paired with an incoming dNTP or modified nucleotide triphosphate. The ternary complex of hpol{iota} inserting N-MC-dATP opposite dT reveals that the adenine ring is stabilized in the anti orientation about the pseudo-glycosyl torsion angle, which mimics precisely the mutagenic arrangement of dGTP:dT normally preferred by hpol{iota}. The stabilized anti conformation occurs without notable contacts from the protein but likely results from constraints imposed by the bicyclo[3.1.0]hexane scaffold of the modified nucleotide. Unmodified dATP and South-MC-dATP each adopt syn glycosyl orientations to form Hoogsteen base pairs with dT. The Hoogsteen orientation exhibits weaker base-stacking interactions and is less catalytically favorable than anti N-MC-dATP. Thus, N-MC-dATP corrects the error-prone nature of hpol{iota} by preventing the Hoogsteen base-pairing mode normally observed for hpol{iota}-catalyzed insertion of dATP opposite dT. These results provide a previously unrecognized means of altering the efficiency and the fidelity of a human translesion DNA polymerase.

Ketkar, Amit; Zafar, Maroof K.; Banerjee, Surajit; Marquez, Victor E.; Egli, Martin; Eoff, Robert L. (Cornell); (Vanderbilt); (NCI); (Arkansas)

2012-10-25T23:59:59.000Z

465

Mass spectrometric characterization of sequence-specific complexes of DNA and transcription factor PU.1 DNA binding domain  

SciTech Connect (OSTI)

Electrospray ionization mass spectrometry (ESI-MS) has been used to study the noncovalent interaction of the 13.5-kDa DNA binding domain of PU.1 (PU.1-DBD) with specific double-stranded DNA (dsDNA) target molecules. Mixtures of PU.1-DBD protein and wildtype target DNA sequence yielded ESI-MS spectra showing only protein-dsDNA complex ions of 1:1 stoichiometry and free dsDNA. When PU.1-DBD protein, wild type target DNA, and a mutant target DNA lacking the consensus sequence were mixed, only the 1:1 complex with the wild-type DNA was observed, consistent with gel electrophoresis mobility shift assay results, demonstrating the observation of sequence-specific protein-dsDNA complexes using ESI-MS. 22 refs., 5 figs., 1 tab.

Cheng, Xueheng; Harms, A.C.; Bruce, J.E. [Pacific Northwest National Lab., Richland, WA (United States)] [and others] [Pacific Northwest National Lab., Richland, WA (United States); and others

1996-07-15T23:59:59.000Z

466

A 3D Orthotropic Strain-Rate Dependent Elastic Damage Material Model.  

SciTech Connect (OSTI)

A three dimensional orthotropic elastic constitutive model with continuum damage and cohesive based fracture is implemented for a general polymer matrix composite lamina. The formulation assumes the possibility of distributed (continuum) damage followed b y localized damage. The current damage activation functions are simply partially interactive quadratic strain criteria . However, the code structure allows for changes in the functions without extraordinary effort. The material model formulation, implementation, characterization and use cases are presented.

English, Shawn Allen

2014-09-01T23:59:59.000Z

467

Chemical Spill Response Procedure Initial Response  

E-Print Network [OSTI]

Chemical Spill Response Procedure Initial Response 1. Advise lab occupants of the spill such as quantity spilled and chemical name. Risk Assessment 3. Conduct an initial risk assessment to determine if to the chemical spill. This link can be found at the bottom of the Campus Security homepage, http

468

Thermal imaging investigation of modified fused silica at surface damage sites for understanding the underlying mechanisms of damage growth  

SciTech Connect (OSTI)

We use an infrared thermal imaging system in combination with a fluorescence microscope to map the dynamics of the local surface temperature and fluorescence intensity under cw, UV excitation of laser-modified fused silica within a damage site. Based on a thermal diffusion model, we estimate the energy deposited via linear absorption mechanisms and derive the linear absorption coefficient of the modified material. The results indicate that the damage growth mechanism is not entirely based on linear absorption. Specifically, the absorption cross-section derived above would prove insufficient to cause a significant increase in the temperature of the modified material under nanosecond, pulsed excitation (via linear absorption at ICF laser fluences). In addition, irreversible changes in the absorption cross-section following extended cw, UV laser exposure were observed.

Negres, R A; Burke, M W; DeMange, P; Sutton, S B; Feit, M D; Demos, S G

2006-11-01T23:59:59.000Z

469

AFM CHARACTERIZATION OF RAMAN LASER INDUCED DAMAGE ON CDZNTECRYSTAL SURFACES  

SciTech Connect (OSTI)

High quality CdZnTe (or CZT) crystals have the potential for use in room temperature gamma-ray and X-ray spectrometers. Over the last decade, the methods for growing high quality CZT have improved the quality of the produced crystals however there are material features that can influence the performance of these materials as radiation detectors. The presence of structural heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity), and secondary phases (SPs) can have an impact on the detector performance. There is considerable need for reliable and reproducible characterization methods for the measurement of crystal quality. With improvements in material characterization and synthesis, these crystals may become suitable for widespread use in gamma radiation detection. Characterization techniques currently utilized to test for quality and/or to predict performance of the crystal as a gamma-ray detector include infrared (IR) transmission imaging, synchrotron X-ray topography, photoluminescence spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Raman spectroscopy. In some cases, damage caused by characterization methods can have deleterious effects on the crystal performance. The availability of non-destructive analysis techniques is essential to validate a crystal's quality and its ability to be used for either qualitative or quantitative gamma-ray or X-ray detection. The work presented herein discusses the damage that occurs during characterization of the CZT surface by a laser during Raman spectroscopy, even at minimal laser powers. Previous Raman studies have shown that the localized annealing from tightly focused, low powered lasers results in areas of higher Te concentration on the CZT surface. This type of laser damage on the surface resulted in decreased detector performance which was most likely due to increased leakage current caused by areas of higher Te concentration. In this study, AFM was used to characterize the extent of damage to the CZT crystal surface following exposure to a Raman laser. AFM data reveal localized surface damage and increased conductivity in the areas exposed to the Raman laser beam.

Teague, L.; Duff, M.

2008-10-07T23:59:59.000Z

470

DETECTION OF IMPULSE-LIKE AIRBORNE SOUND FOR DAMAGE IDENTIFICATION IN ROTOR BLADES OF WIND TURBINES  

E-Print Network [OSTI]

DETECTION OF IMPULSE-LIKE AIRBORNE SOUND FOR DAMAGE IDENTIFICATION IN ROTOR BLADES OF WIND TURBINES burdens of wind turbines. To detect damage of rotor blades, several research projects focus on an acoustic, rotor blade, wind turbine INTRODUCTION There are several publications of non destructive damage

Boyer, Edmond

471

PLASTICITY OF DAMAGED SOLIDS AND SHEAR BAND LOCALIZATION MARIA K.DUSZEK and PIOTR PERZYNA  

E-Print Network [OSTI]

694 PLASTICITY OF DAMAGED SOLIDS AND SHEAR BAND LOCALIZATION MARIA K.DUSZEK and PIOTR PERZYNA of shear band localization conditions for finite elastic-plastic rate independent deformations of damaged for elastic-plastic solids when iso- tropic and kinematic hardening effects and micro-damage process are taken

Boyer, Edmond

472

Anisotropic damage modelling of biaxial behaviour and rupture of concrete structures  

E-Print Network [OSTI]

Continuum Damage Mechanics at the Representative Element Volume scale is a relevant tool to deal with largeAnisotropic damage modelling of biaxial behaviour and rupture of concrete structures Ragueneau F with damage induced anisotropy modelling for concrete-like materials. A thermodynamics based constitutive

Boyer, Edmond

473

N d'ordre : 2011-ISAL-0147 Annee 2011 Ductile damage characterization in  

E-Print Network [OSTI]

N d'ordre : 2011-ISAL-0147 Ann´ee 2011 Th`ese Ductile damage characterization in Dual-Phase steels-5Oct2012 #12;Ductile damage characterization in Dual-Phase steels using X-ray tomography Abstract to stress and to damage, the Dual-Phase steels (DP) present an acceptable strength/ductility compromise

Paris-Sud XI, Université de

474

RESEARCH ARTICLE Increase in crop damage caused by wild boar (Sus scrofa L.)  

E-Print Network [OSTI]

RESEARCH ARTICLE Increase in crop damage caused by wild boar (Sus scrofa L.): the "refuge effect /Published online: 14 October 2011 Abstract The occurrence of crop damage by wild boars raised dramatically, including hunting, can play a relevant role in causing crop damage. We studied a Mediterranean area

Boyer, Edmond

475

Adaptive modeling of environmental e ects in modal parameters for damage detection in civil structures  

E-Print Network [OSTI]

Adaptive modeling of environmental e ects in modal parameters for damage detection in civil parameters due to temperature changes from those caused by structural damage or other environmental e ects to environmental factors can be far larger than those caused by structural damage. During damp weather, for example

Stanford University

476

Optical selection and collection of DNA fragments  

DOE Patents [OSTI]

Optical selection and collection of DNA fragments. The present invention includes the optical selection and collection of large (>.mu.g) quantities of clonable, chromosome-specific DNA from a sample of chromosomes. Chromosome selection is based on selective, irreversible photoinactivation of unwanted chromosomal DNA. Although more general procedures may be envisioned, the invention is demonstrated by processing chromosomes in a conventional flow cytometry apparatus, but where no droplets are generated. All chromosomes in the sample are first stained with at least one fluorescent analytic dye and bonded to a photochemically active species which can render chromosomal DNA unclonable if activated. After passing through analyzing light beam(s), unwanted chromosomes are irradiated using light which is absorbed by the photochemically active species, thereby causing photoinactivation. As desired chromosomes pass this photoinactivation point, the inactivating light source is deflected by an optical modulator; hence, desired chromosomes are not photoinactivated and remain clonable. The selection and photoinactivation processes take place on a microsecond timescale. By eliminating droplet formation, chromosome selection rates 50 times greater than those possible with conventional chromosome sorters may be obtained. Thus, usable quantities of clonable DNA from any source thereof may be collected.

Roslaniec, Mary C. (Los Alamos, NM); Martin, John C. (Los Alamos, NM); Jett, James H. (Los Alamos, NM); Cram, L. Scott (Los Alamos, NM)

1998-01-01T23:59:59.000Z

477

DNA nanotechnology: understanding and optimisation through simulation  

E-Print Network [OSTI]

DNA nanotechnology promises to provide controllable self-assembly on the nanoscale, allowing for the design of static structures, dynamic machines and computational architectures. In this article I review the state-of-the art of DNA nanotechnology, highlighting the need for a more detailed understanding of the key processes, both in terms of theoretical modelling and experimental characterisation. I then consider coarse-grained models of DNA, mesoscale descriptions that have the potential to provide great insight into the operation of DNA nanotechnology if they are well designed. In particular, I discuss a number of nanotechnological systems that have been studied with oxDNA, a recently developed coarse-grained model, highlighting the subtle interplay of kinetic, thermodynamic and mechanical factors that can determine behaviour. Finally, new results highlighting the importance of mechanical tension in the operation of a two-footed walker are presented, demonstrating that recovery from an unintended `overstepped' configuration can be accelerated by three to four orders of magnitude by application of a moderate tension to the walker's track. More generally, the walker illustrates the possibility of biasing strand-displacement processes to affect the overall rate.

Thomas E. Ouldridge

2014-11-07T23:59:59.000Z

478

Fission product behavior during the PBF (Power Burst Facility) Severe Fuel Damage Test 1-1  

SciTech Connect (OSTI)

In response to the accident at Three Mile Island Unit 2 (TMI-2), the United States Nuclear Regulatory Commission (USNRC) initiated a series of Severe Fuel Damage tests that were performed in the Power Burst Facility at the Idaho National Engineering Laboratory to obtain data necessary to understand (a) fission product release, transport, and deposition; (b) hydrogen generation; and (c) fuel/cladding material behavior during degraded core accidents. Data are presented about fission product behavior noted during the second experiment of this series, the Severe Fuel Damage Test 1-1, with an in-depth analysis of the fission product release, transport, and deposition phenomena that were observed. Real-time release and transport data of certain fission products were obtained from on-line gamma spectroscopy measurements. Liquid and gas effluent grab samples were collected at selected periods during the test transient. Additional information was obtained from steamline deposition analysis. From these and other data, fission product release rates and total release fractions are estimated and compared with predicted release behavior using current models. Fission product distributions and a mass balance are also summarized, and certain probable chemical forms are predicted for iodine, cesium, and tellurium. An in-depth evaluation of phenomena affecting the behavior of the high-volatility fission products - xenon, krypton, iodine, cesium, and tellurium - is presented. Analysis indicates that volatile release from fuel is strongly influenced by parameters other than fuel temperature. Fission product behavior during transport through the Power Burst Facility effluent line to the fission product monitoring system is assessed. Tellurium release behavior is also examined relatve to the extent of Zircaloy cladding oxidation. 81 fig., 53 tabs.

Hartwell, J K; Petti, D A; Hagrman, D L; Jensen, S M; Cronenberg, A W

1987-05-01T23:59:59.000Z

479

Laser damage resistant pits in dielectric coatings created by femtosecond laser machining  

SciTech Connect (OSTI)

Replacing growing damage sites with benign, laser damage resistant features in multilayer dielectric films may enable large mirrors to be operated at significantly higher fluences. Laser damage resistant features have been created in high reflecting coatings on glass substrates using femtosecond laser machining. These prototype features have been damage tested to over 40 J/cm{sup 2} (1064nm, 3ns pulselength) and have been shown not to damage upon repeated irradiation at 40J/cm{sup 2}. Further work to optimize feature shape and laser machining parameters is ongoing.

Wolfe, J; Roger Qiu, ,; Stolz, C; Thomas, M; Martinez, C; Ozkan, A

2009-11-03T23:59:59.000Z

480

Thermodynamic damage mechanism of transparent films caused by a low-power laser  

SciTech Connect (OSTI)

A new model for analyzing the laser-induced damage process is provided. In many damage pits, the melted residue can been found. This is evidence of the phase change of materials. Therefore the phase change of materials is incorporated into the mechanical damage mechanism of films. Three sequential stages are discussed: no phase change, liquid phase change, and gas phase change. To study the damage mechanism and process, two kinds of stress have been considered: thermal stress and deformation stress. The former is caused by the temperature gradient and the latter is caused by high-pressure drive deformation. The theory described can determine the size of the damage pit.

Xia Zhilin; Shao Jianda; Fan Zhengxiu; Wu Shigang

2006-11-10T23:59:59.000Z

Note: This page contains sample records for the topic "dna damage response" from the National Library of EnergyBeta (NLEBeta).
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481

The versatile E. coli adaptive response protein AlkB mitigates toxicity and mutagenicity of etheno-, ethano-, and methyl-modified bases in vivo  

E-Print Network [OSTI]

The Escherichia coli AlkB protein is an exceptionally versatile DNA repair enzyme. Its expression is induced upon exposure to alkylating agents as part of the Ada-mediated adaptive response. This member of the ac-ketoglu ...

Frick, Lauren Elizabeth

2007-01-01T23:59:59.000Z

482

A Summary of Recent Damage-Initiation Experiments on KDP Crystals  

SciTech Connect (OSTI)

We summarize recent investigations of the density and morphology of bulk damage in KDP crystals as a function of pulse duration, temporal profile, wavelength, and energy fluence. As previously reported by Runkel et al., we also find that the size of bulk damage sites varies roughly linearly with pulse duration for pulses between 1 ns and 9 ns. However this trend no longer applies at pulse durations below 1 ns. Experiments measuring the damage density and size distribution as a function of wavelength confirm many previous works which indicated a strong dependence of damage density with wavelength. However, we also find that the size of damage sites is relatively insensitive to wavelength. Further we see damage due to Flat-In-Time (FIT) pulses has different pulse length and fluence dependence than Gaussian pulses. We demonstrate that a simple thermal diffusion model can account for observed differences in damage densities due to square and Gaussian temporally shaped pulses of equal fluence. Moreover, we show that the key laser parameter governing size of the bulk damage sites is the length of time the pulse remains above a specific intensity. The different dependences of damage density and damage site size on laser parameters suggest different absorption mechanisms early and late in the damaging pulse.

Carr, C W; Feit, M D; Rubenchik, A M; Trenholme, J B; Spaeth, M L

2005-11-07T23:59:59.000Z

483